Science.gov

Sample records for sorbent development evaluation

  1. EVALUATION OF FGD DRY INJECTION SORBENTS AND ADDITIVES - VOLUME 1 - DEVELOPMENT OF HIGH REACTIVITY SORBENTS

    EPA Science Inventory

    The report discusses recent work addressing lime enhancement by slurrying with siliceous materials and testing in a laboratory packed-bed reactor, as part of EPA's efforts to develop low cost, retrofit flue gas cleaning technology, including the development of highly reactive sor...

  2. Development and evaluation of a silver mordenite composite sorbent for the partitioning of xenon from krypton in gas compositions

    SciTech Connect

    Garn, Troy G.; Greenhalgh, Mitchell; Law, Jack D.

    2015-12-22

    A new engineered form composite sorbent for the selective separation of xenon from krypton in simulant composition off-gas streams resulting from the reprocessing of used nuclear fuel has been developed and evaluated. A sodium mordenite powder was incorporated into a macroporous polymer binder, formed into spherical beads and successfully converted to a 9 wt.% silver form composite sorbent. The final engineered form sorbent retained the characteristic surface area indicative of sodium mordenite powder. The sorbent was evaluated for xenon adsorption potential with capacities measured as high as 30 millimoles of xenon per kilogram of sorbent achieved at ambient temperature and 460 millimoles of xenon per kilogram sorbent at 220 K. Xenon/krypton selectivity was calculated to be 22.4 with a 1020 µL/L xenon, 150 µL/L krypton in a balance of air feed gas at 220 K. Furthermore, adsorption/desorption thermal cycling effects were evaluated with results indicating sorbent performance was not significantly impacted while undergoing numerous adsorption/desorption thermal cycles.

  3. Development and evaluation of a silver mordenite composite sorbent for the partitioning of xenon from krypton in gas compositions

    DOE PAGES

    Garn, Troy G.; Greenhalgh, Mitchell; Law, Jack D.

    2015-12-22

    A new engineered form composite sorbent for the selective separation of xenon from krypton in simulant composition off-gas streams resulting from the reprocessing of used nuclear fuel has been developed and evaluated. A sodium mordenite powder was incorporated into a macroporous polymer binder, formed into spherical beads and successfully converted to a 9 wt.% silver form composite sorbent. The final engineered form sorbent retained the characteristic surface area indicative of sodium mordenite powder. The sorbent was evaluated for xenon adsorption potential with capacities measured as high as 30 millimoles of xenon per kilogram of sorbent achieved at ambient temperature andmore » 460 millimoles of xenon per kilogram sorbent at 220 K. Xenon/krypton selectivity was calculated to be 22.4 with a 1020 µL/L xenon, 150 µL/L krypton in a balance of air feed gas at 220 K. Furthermore, adsorption/desorption thermal cycling effects were evaluated with results indicating sorbent performance was not significantly impacted while undergoing numerous adsorption/desorption thermal cycles.« less

  4. ADVANCED SORBENT DEVELOPMENT PROGRAM

    SciTech Connect

    Unknown

    1998-06-16

    The overall objective of this program was to develop regenerable sorbents for use in the temperature range of 343 to 538 C (650 to 1000 F) to remove hydrogen sulfide (H{sub 2}S) from coal-derived fuel gases in a fluidized-bed reactor. The goal was to develop sorbents that are capable of reducing the H{sub 2}S level in the fuel gas to less than 20 ppmv in the specified temperature range and pressures in the range of 1 to 20 atmospheres, with chemical characteristics that permit cyclic regeneration over many cycles without a drastic loss of activity, as well as physical characteristics that are compatible with the fluidized bed application.

  5. Development and Evaluation of Nanoscale Sorbents for Mercury Capture from Warm Fuel Gas

    SciTech Connect

    Raja A. Jadhav

    2006-05-31

    Several different types of nanocrystalline metal oxide sorbents were synthesized and evaluated for capture of mercury (Hg) from coal-gasifier warm fuel gas. Detailed experimental studies were carried out to understand the fundamental mechanism of interaction between mercury and nanocrystalline sorbents over a range of fuel gas conditions. The metal oxide sorbents evaluated in this work included those prepared by GTI's subcontractor NanoScale Materials, Inc. (NanoScale) as well as those prepared in-house. These sorbents were evaluated for mercury capture in GTI's Mercury Sorbent Testing System. Initial experiments were focused on sorbent evaluation for mercury capture in N{sub 2} stream over the temperature range 423-533 K. These exploratory studies demonstrated that NanoActive Cr{sub 2}O{sub 3} along with its supported form was the most active of the sorbent evaluated. The capture of Hg decreased with temperature, which suggested that physical adsorption was the dominant mechanism of Hg capture. Desorption studies on spent sorbents indicated that a major portion of Hg was attached to the sorbent by strong bonds, which suggested that Hg was oxidized by the O atoms of the metal oxides, thus forming a strong Hg-O bond with the oxide. Initial screening studies also indicated that sulfided form of CuO/alumina was the most active for Hg capture, therefore was selected for detailed evaluation in simulated fuel gas (SFG). It was found that such supported CuO sorbents had high Hg-sorption capacity in the presence of H{sub 2}, provided the gas also contained H{sub 2}S. Exposure of supported CuO sorbent to H{sub 2}S results in the formation of CuS, which is an active sorbent for Hg capture. Sulfur atom in CuS forms a bond with Hg that results into its capture. Although thermodynamically CuS is predicted to form unreactive Cu{sub 2}S form when exposed to H{sub 2}, it is hypothesized that Cu atoms in such supported sorbents are in ''dispersed'' form, with two Cu atoms separated

  6. Novel sorbent development and evaluation for the capture of krypton and xenon from nuclear fuel reprocessing off-gas stream

    SciTech Connect

    Garn, T.G.; Greenhalgh, M.R.; Law, J.D.

    2013-07-01

    The release of volatile radionuclides generated during Used Nuclear Fuel reprocessing in the US will most certainly need to be controlled to meet US regulatory emission limits. A US DOE sponsored Off-Gas Sigma Team has been tasked with a multi-lab collaborative research and development effort to investigate and evaluate emissions and immobilization control technologies for the volatile radioactive species generated from commercial Used Nuclear Fuel (UNF) Reprocessing. Physical Adsorption technology is a simpler and potential economical alternative to cryogenic distillation processes that can be used for the capture of krypton and xenon and has resulted in a novel composite sorbent development procedure using synthesized mordenite as the active material. Utilizing the sorbent development procedure, Idaho National Laboratory sigma team members have developed two composite sorbents that have been evaluated for krypton and xenon capacities at ambient and 191 K temperature using numerous test gas compositions. Adsorption isotherms have been generated to predict equilibration and maximum capacities enabling modeling to support process equipment scale-up. (authors)

  7. Novel Sorbent Development and Evaluation for the Capture of Krypton and Xenon from Nuclear Fuel Reprocessing Off-Gas Streams

    SciTech Connect

    Troy G. Garn; Mitchell R. Greenhalgh; Jack D. Law

    2013-09-01

    The release of volatile radionuclides generated during Used Nuclear Fuel reprocessing in the US will most certainly need to be controlled to meet US regulatory emission limits. A US DOE sponsored Off-Gas Sigma Team has been tasked with a multi-lab collaborative research and development effort to investigate and evaluate emissions and immobilization control technologies for the volatile radioactive species generated from commercial Used Nuclear Fuel (UNF) Reprocessing. Physical Adsorption technology is a simpler and potential economical alternative to cryogenic distillation processes that can be used for the capture of krypton and xenon and has resulted in a novel composite sorbent development procedure using synthesized mordenite as the active material. Utilizing the sorbent development procedure, INL sigma team members have developed two composite sorbents that have been evaluated for krypton and xenon capacities at ambient and 191 K temperature using numerous test gas compositions. Adsorption isotherms have been generated to predict equilibration and maximum capacities enabling modeling to support process equipment scale-up.

  8. Novel Sorbent Development and Evaluation for the Capture of Krypton and Xenon from Nuclear Fuel Reprocessing Off-Gas Streams

    SciTech Connect

    Troy G. Garn; Mitchell R. Greenhalgh; Jack D. Law

    2013-10-01

    The release of volatile radionuclides generated during Used Nuclear Fuel reprocessing in the US will most certainly need to be controlled to meet US regulatory emission limits. A US DOE sponsored Off-Gas Sigma Team has been tasked with a multi-lab collaborative research and development effort to investigate and evaluate emissions and immobilization control technologies for the volatile radioactive species generated from commercial Used Nuclear Fuel (UNF) Reprocessing. Physical Adsorption technology is a simpler and potential economical alternative to cryogenic distillation processes that can be used for the capture of krypton and xenon and has resulted in a novel composite sorbent development procedure using synthesized mordenite as the active material. Utilizing the sorbent development procedure, INL sigma team members have developed two composite sorbents that have been evaluated for krypton and xenon capacities at ambient and 191 K temperature using numerous test gas compositions. Adsorption isotherms have been generated to predict equilibration and maximum capacities enabling modeling to support process equipment scale-up.

  9. Development of a Test for Evaluation of the Hydrothermal Stability of Sorbents Used in Closed-Loop CO2 Removal Systems

    NASA Technical Reports Server (NTRS)

    Knox, James C.; Gauto, Hernando; Miller, Lee A.

    2015-01-01

    The International Space Station Carbon Dioxide Removal Assembly uses zeolite 5A molecular sieve material packed into beds for the capture of cabin CO2. The beds are cyclically heated to drive off the CO2 and restore the removal capacity. Over time, the sorbent material has been found to break down resulting in dust that restricts flow through the beds. Humidity adsorbed in the 5A zeolite when it is heated is a suspected cause of this sorbent degradation. To evaluate the impact of adsorbed water during thermal cycling, the Hydrothermal Stability Test was developed. The test configuration provides comparative side-by-side flow restriction data for two sorbent materials at specifically controlled humidity levels. While the initial focus of the testing is on 5A zeolite materials currently used on the ISS, the system will also be used to evaluate future candidate materials. This paper describes the approach, the test system, current results, and future testing.

  10. ADVANCED SORBENT DEVELOPMENT PROGRAM; DEVELOPMENT OF SORBENTS FOR MOVING-BED AND FLUIDIZED-BED APPLICATIONS

    SciTech Connect

    AYALA, R E; VENKATARAMANI, V S

    1998-09-30

    assessment and a market plan for large-scale fabrication of sorbents were developed. As an optional task, long-term bench-scale tests of the best moving-bed sorbents were conducted. Starting from thermodynamic calculations, several metal oxides were identified for potential use as hot gas cleanup sorbents using constructed phase stability diagrams and laboratory screening of various mixed-metal oxide formulations. Modified zinc titanates and other proprietary metal oxide formulations were evaluated at the bench scale and many of them found to be acceptable for operation in the target desulfurization temperature range of 370 °C (700 °F) to 538 °C (1000 °F) and regeneration tempera-tures up to 760 °C (1400 °F). Further work is still needed to reduce the batch-to-batch repeatability in the fabrication of modified zinc titanates for larger scale applications. The information presented in this Volume 1 report contains the results of moving-bed sorbent develop-ment at General Electric's Corporate Research and Development (GE-CRD). A separate Volume 2 report contains the results of the subcontract on fluidized-bed sorbent development at the Institute of Gas Technology (IGT).

  11. ADVANCED SORBENT DEVELOPMENT PROGRAM DEVELOPMENT OF SORBENTS FOR MOVING-BED AND FLUIDIZED-BED APPLICATIONS

    SciTech Connect

    R.E Ayala; V.S. Venkataramani; Javad Abbasian; Rachid B. Slimane; Brett E. Williams; Minoo K. Zarnegar; James R. Wangerow; Andy H. Hill

    2000-03-31

    and a market plan for large-scale fabrication of sorbents were developed. As an optional task, long-term bench-scale tests of the best moving-bed sorbents were conducted. Starting from thermodynamic calculations, several metal oxides were identified for potential use as hot gas cleanup sorbents using constructed phase stability diagrams and laboratory screening of various mixed-metal oxide formulations. Modified zinc titanates and other proprietary metal oxide formulations were evaluated at the bench scale and many of them found to be acceptable for operation in the target desulfurization temperature range of 370 C (700 F) to 538 C (1000 F) and regeneration temperatures up to 760 C (1400 F). Further work is still needed to reduce the batch-to-batch repeatability in the fabrication of modified zinc titanates for larger scale applications. The information presented in this Volume 1 report contains the results of moving-bed sorbent development at General Electric's Corporate Research and Development (GE-CRD). A separate Volume 2 report contains the results of the subcontract on fluidized-bed sorbent development at the Institute of Gas Technology (IGT).

  12. Desulfurization sorbent development activities at METC

    SciTech Connect

    Siriwardane, R.V.

    1995-06-01

    Development of a suitable regenerable sorbent is a major barrier issue in the hot gas cleanup program for integrated gasification combined-cycle (IGCC) systems. This has been a challenging problem during the last 20 years, since many of the sorbents developed in the program could not retain their reactivity and physical integrity during repeated cycles of sulfidation and regeneration reactions. A series of promising sorbents (METC 2-10), which were capable of sustaining their reactivity and physical integrity during repeated sulfidation/ regeneration cycles, have been developed at the Morgantown Energy Technology Center (METC). These sorbents were tested both in low-pressure (260 KPa/23 psig) and high-pressure (520 KPa/60.7 psig) fixed-bed reactors at 538{degrees}C (1000{degrees}F) with simulated coal gas. High-pressure testing was continued for 20 cycles with steam regeneration. A major research goal during the last year was to lower the cost of materials utilized during the sorbent preparation. The METC 9 sorbent was prepared by substituting low-cost materials for some of the materials in METC 6 sorbent. The sulfur capacity of the two sorbents were similar during the 20-cycle testing. METC 2 sorbent was exposed to coal gas in the Modular Gas Cleanup Rig and it was later tested in the high-pressure fixed-bed reactor. The reactivity of the METC 2 sorbent was unaffected by the exposure to the coal gas. Development of these sorbents will be continued for both fluid-bed and moving-bed applications.

  13. VALUE-ADDED SORBENT DEVELOPMENT

    SciTech Connect

    Grant E. Dunham; Edwin S. Olson; Stanley J. Miller

    2000-07-01

    On a worldwide basis, the projected increase in coal usage over the next two decades in China, India, and Indonesia will dwarf the current U.S. coal consumption of 1 billion tons/year. Therefore, in the United States, coal will be the dominant source of mercury emissions, and worldwide, coal may be the cause of significantly increased mercury emissions unless an effective control strategy is implemented. However, there is much uncertainty over the most technically sound and cost-effective approach for reducing mercury emissions from coal-fired boilers. Several approaches are suggested for mercury control from coal-fired boilers, including enhancing the ability of wet scrubbers to retain mercury. However, many coal-fired boilers are not equipped with wet scrubbers. On the other hand, since almost all coal-fired boilers are equipped with either an electrostatic precipitator (ESP) or a baghouse, sorbent injection upstream of either an ESP or baghouse appears attractive, because it has the potential to control both Hg{sup 0} and Hg{sup 2+}, would appear to be easy to retrofit, and would be applicable to both industrial and utility boilers. Since mercury in the gas stream from coal combustion is present in only trace quantities, only very small amounts of sorbent may be necessary. If we assume a mercury concentration of 10 {micro}g/m{sup 3} and a sorbent-to-mercury mass ratio of 1000:1, the required sorbent loading is 10 mg/m{sup 3}, which is only 0.1% to 0.2% of a typical dust loading of 5-10 g/m{sup 3} (2.2-4.4 grains/scf). This amount of additional sorbent material in the ash would appear to be negligible and would not be expected to have an impact on control device performance or ash utilization. Accomplishing effective mercury control with sorbent injection upstream of a particulate control device requires several critical steps: (1) Dispersion of the small sorbent particles and mixing with the flue gas must be adequate to ensure that all of the gas is effectively

  14. Regenerable Sorbent Development for Sulfur, Chloride and Ammonia Removal from Coal-Derived Synthesis Gas

    SciTech Connect

    Siriwardane, R.V.; Tian, H.; Simonyi, T.; Webster, T.

    2007-08-01

    A large number of components in coal form corrosive and toxic compounds during coal gasification processes. DOE’s NETL aims to reduce contaminants to parts per billion in order to utilize gasification gas streams in fuel cell applications. Even more stringent requirements are expected if the fuel is to be utilized in chemical production applications. Regenerable hydrogen sulfide removal sorbents have been developed at NETL. These sorbents can remove the hydrogen sulfide to ppb range at 316 °C and at 20 atmospheres. The sorbent can be regenerated with oxygen. Reactivity and physical durability of the sorbent did not change during the multi-cycle tests. The sorbent development work has been extended to include the removal of other major impurities, such as HCl and NH3. The sorbents for HCl removal that are available today are not regenerable. Regenerable HCl removal sorbents have been developed at NETL. These sorbents can remove HCl to ppb range at 300 °C to 500 °C. The sorbent can be regenerated with oxygen. Results of TGA and bench-scale flow reactor tests with both regenerable and non-regenerable HCl removal sorbents will be discussed in the paper. Bench-scale reactor tests were also conducted with NH3 removal sorbents. The results indicated that the sorbents have a high removal capacity and good regenerability during the multi-cycle tests. Future emphasis of the NETL coal gasification/cleanup program is to develop multi-functional sorbents to remove multiple impurities in order to minimize the steps involved in the cleanup systems. To accomplish this goal, a regenerable sorbent capable of removing both HCl and H2S was developed. The results of the TGA conducted with the sorbent to evaluate the feasibility of both H2S and HCl sorption will be discussed in this paper.

  15. Sorbent development for transport reactor applications

    SciTech Connect

    Gupta, R.P.; Turk, B.S.; Vierheilig, A.A.; Cicero, D.C.

    1998-12-31

    Advanced power generation systems employing gasification of carbonaceous fuels offer increased efficiency and reduced emissions over pulverized coal-fired boiler systems currently in service. Integrated gasification combined cycle (IGCC) is the leading gasification-based system which is being advanced worldwide to produce electricity from carbonaceous fuels. This technology has the potential to reduce sulfur and nitrogen emissions the precursors of acid-rain and could lead to significant reductions in carbon dioxide emissions, which, it is believed, are major contributors to global warming. Successful commercialization of the IGCC technology requires economic competitiveness with other power generation systems. This economic competitiveness has propelled research and development of gas desulfurization systems. A number of mixed metal oxide sorbents have been investigated for removal of reduced sulfur species (H{sub 2}S, COS, CS{sub 2}, etc.) at high-temperature, high-pressure (HTHP) conditions, the best candidates have been the ZnO-based sorbents because of their ability to reduce the fuel gas sulfur level to a few parts per million by volume (ppmv). The work described in this paper deals with the development of zinc titanate sorbents for transport reactor applications.

  16. Evaluation of Sorbent Injection for Mercury Control

    SciTech Connect

    Sharon Sjostrom

    2005-12-30

    The power industry in the U.S. is faced with meeting new regulations to reduce the emissions of mercury compounds from coal-fired plants. These regulations are directed at the existing fleet of nearly 1,100 boilers. These plants are relatively old with an average age of over 40 years. Although most of these units are capable of operating for many additional years, there is a desire to minimize large capital expenditures because of the reduced (and unknown) remaining life of the plant to amortize the project. Injecting a sorbent such as powdered activated carbon into the flue gas represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. This is the final site report for tests conducted at Laramie River Station Unit 3, one of five sites evaluated in this DOE/NETL program. The overall objective of the test program is to evaluate the capabilities of activated carbon injection at five plants: Sunflower Electric's Holcomb Station Unit 1, AmerenUE's Meramec Station Unit 2, Missouri Basin Power Project's Laramie River Station Unit 3, Detroit Edison's Monroe Power Plant Unit 4, and AEP's Conesville Station Unit 6. These plants have configurations that together represent 78% of the existing coal-fired generation plants. The goals for the program established by DOE/NETL are to reduce the uncontrolled mercury emissions by 50 to 70% at a cost 25 to 50% lower than the benchmark established by DOE of $60,000/lb mercury removed. The goals of the program were exceeded at Laramie River Station by achieving over 90% mercury removal at a sorbent cost of $3,980/lb ($660/oz) mercury removed for a coal mercury content of 7.9 lb/TBtu.

  17. Performance Evaluation of Engineered Structured Sorbents for Atmosphere Revitalization Systems On Board Crewed Space Vehicles and Habitats

    NASA Technical Reports Server (NTRS)

    Howard, David F.; Perry, Jay L.; Knox, James C.; Junaedi, Christian; Roychoudhury, Subir

    2011-01-01

    Engineered structured (ES) sorbents are being developed to meet the technical challenges of future crewed space exploration missions. ES sorbents offer the inherent performance and safety attributes of zeolite and other physical adsorbents but with greater structural integrity and process control to improve durability and efficiency over packed beds. ES sorbent techniques that are explored include thermally linked and pressure-swing adsorption beds for water-save dehumidification and sorbent-coated metal meshes for residual drying, trace contaminant control, and carbon dioxide control. Results from sub-scale performance evaluations of a thermally linked pressure-swing adsorbent bed and an integrated sub-scale ES sorbent system are discussed.

  18. Evaluation of Sorbent Injection for Mercury Control

    SciTech Connect

    Sharon Sjostrom

    2004-10-29

    The power industry in the U.S. is faced with meeting new regulations to reduce the emissions of mercury compounds from coal-fired plants. These regulations are directed at the existing fleet of nearly 1,100 boilers. These plants are relatively old with an average age of over 40 years. Although most of these units are capable of operating for many additional years, there is a desire to minimize large capital expenditures because of the reduced (and unknown) remaining life of the plant to amortize the project. Injecting a sorbent such as powdered activated carbon into the flue gas represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. The overall objective of the test program described in this quarterly report is to evaluate the capabilities of activated carbon injection at four plants with configurations that together represent 78% of the existing coal-fired generation plants. This technology was successfully evaluated in NETL's Phase I tests at scales up to 150 MW, on plants burning subbituminous and bituminous coals and with ESPs and fabric filters. The tests also identified issues that still need to be addressed, such as evaluating performance on other configurations, optimizing sorbent usage (costs), and gathering longer-term operating data to address concerns about the impact of activated carbon on plant equipment and operations. The four sites identified for testing are Sunflower Electric's Holcomb Station, AmerenUE's Meramec Station, AEP's Conesville Station, and a site burning a blend of bituminous and subbituminous coals with a cold-side ESP. This is the fourth quarterly report for this project. Long-term testing was completed at Holcomb during this reporting period and baseline testing at Meramec was begun. Preliminary results from long-term testing at Holcomb are included in this report. Planning information for the other three sites is also included. In general, quarterly reports will be used

  19. Evaluation of Sorbent Injection for Mercury Control

    SciTech Connect

    Sharon Sjostrom

    2005-02-02

    The power industry in the U.S. is faced with meeting new regulations to reduce the emissions of mercury compounds from coal-fired plants. These regulations are directed at the existing fleet of nearly 1,100 boilers. These plants are relatively old with an average age of over 40 years. Although most of these units are capable of operating for many additional years, there is a desire to minimize large capital expenditures because of the reduced (and unknown) remaining life of the plant to amortize the project. Injecting a sorbent such as powdered activated carbon into the flue gas represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. The overall objective of the test program described in this quarterly report is to evaluate the capabilities of activated carbon injection at five plants with configurations that together represent 78% of the existing coal-fired generation plants. This technology was successfully evaluated in NETL's Phase I tests at scales up to 150 MW, on plants burning subbituminous and bituminous coals and with ESPs and fabric filters. The tests also identified issues that still need to be addressed, such as evaluating performance on other configurations, optimizing sorbent usage (costs), and gathering longer-term operating data to address concerns about the impact of activated carbon on plant equipment and operations. The four sites identified for testing are Sunflower Electric's Holcomb Station, AmerenUE's Meramec Station, AEP's Conesville Station, and Detroit Edison's Monroe Power Plant. In addition to tests identified for the four main sites, parametric testing at Missouri Basin Power Project's Laramie River Station Unit 3 has been scheduled and made possible through additional costshare participation targeted by team members specifically for tests at Holcomb or a similar plant. This is the fifth quarterly report for this project. Long-term testing was completed at Meramec during this

  20. Evaluation of Sorbent Injection for Mercury Control

    SciTech Connect

    Sharon Sjostrom

    2006-04-30

    The power industry in the U.S. is faced with meeting new regulations to reduce the emissions of mercury compounds from coal-fired plants. These regulations are directed at the existing fleet of nearly 1,100 boilers. These plants are relatively old with an average age of over 40 years. Although most of these units are capable of operating for many additional years, there is a desire to minimize large capital expenditures because of the reduced (and unknown) remaining life of the plant to amortize the project. Injecting a sorbent such as powdered activated carbon into the flue gas represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. This is the final site report for tests conducted at DTE Energy's Monroe Power Plant, one of five sites evaluated in this DOE/NETL program. The overall objective of the test program was to evaluate the capabilities of activated carbon injection at five plants: Sunflower Electric's Holcomb Station Unit 1, AmerenUE's Meramec Station Unit 2, Missouri Basin Power Project's Laramie River Station Unit 3, Detroit Edison's Monroe Power Plant Unit 4, and AEP's Conesville Station Unit 6. These plants have configurations that together represent 78% of the existing coal-fired generation plants. The goals for the program established by DOE/NETL were to reduce the uncontrolled mercury emissions by 50 to 70% at a cost 25 to 50% lower than the target established by DOE of $60,000/lb mercury removed. The results from Monroe indicate that using DARCO{reg_sign} Hg would result in higher mercury removal (80%) at a sorbent cost of $18,000/lb mercury, or 70% lower than the benchmark. These results demonstrate that the goals established by DOE/NETL were exceeded during this test program. The increase in mercury removal over baseline conditions is defined for this program as a comparison in the outlet emissions measured using the Ontario Hydro method during the baseline and long-term test periods

  1. Development of advanced hot-gas desulfurization sorbents. Final report

    SciTech Connect

    Jothimurugesan, K.; Adeyiga, A.A.; Gangwal, S.K.

    1997-10-01

    The objective of this project was to develop hot-gas desulfurization sorbent formulations for relatively lower temperature application, with emphasis on the temperature range from 343--538 C. The candidate sorbents include highly dispersed mixed metal oxides of zinc, iron, copper, cobalt, nickel and molybdenum. The specific objective was to develop suitable sorbents, that would have high and stable surface area and are sufficiently reactive and regenerable at the relatively lower temperatures of interest in this work. Stability of surface area during regeneration was achieved by adding stabilizers. To prevent sulfation, catalyst additives that promote the light-off of the regeneration reaction at lower temperature was considered. Another objective of this study was to develop attrition-resistant advanced hot-gas desulfurization sorbents which show stable and high sulfidation reactivity at 343 to 538 C and regenerability at lower temperatures than leading first generation sorbents.

  2. Development of the advanced coolside sorbent injection process for SO{sub 2}

    SciTech Connect

    Withum, J.A.; Maskew, J.T.; Rosenhoover, W.A.

    1995-11-01

    The goal of this work was to develop a low-capital-cost process capable of over 90% SO{sub 2} removal as an economically attractive option for compliance with the Clean Air Act. The Advanced Coolside Process uses a contactor to simultaneously remove fly ash and saturate the flue gas with water, followed by sorbent injection into the highly humid flue gas and collection of the sorbent by the existing particulate collector High sorbent utilization is achieved by sorbent recycle. The original performance targets of 90% SO{sub 2} removal and 60% sorbent utilization were exceeded in 1000 acfm pilot plant operations using commercial hydrated lime as the only sorbent. Process optimization simplified the process equipment, resulting in significant cost reduction. Recent accomplishments include completion of equipment testing and sorbent optimization, a waste management study, and a long-term performance test. An economic evaluation for the optimized process projects capital costs 55% to 60 % less than those of limestone forced oxidation wet FGD. The projected levelized control cost is 15% to 35% lower than wet FGD (25% lower for a 260 MWe plant burning a 2.5% sulfur coal), depending on plant size and coal sulfur content.

  3. Development of regenerable copper-based sorbents for hot gas cleanup. Technical report, September 1, 1995--November 30, 1995

    SciTech Connect

    Abbasian, J.; Slimane, R.B.; Hill, A.H.

    1995-12-31

    The overall objective of this study is to determine the effectiveness of the copper-chromite sorbent (developed in previous ICCI-funded projects) for longer duration application under optimum conditions in the temperature range of 550{degrees}-650{degrees}C to minimize sorbent reduction and degradation during the cyclic process. To achieve this objective, several formulations of copper chromite sorbents are prepared. These sorbent formulations are screened for their desulfurization and regeneration capability at predetermined temperatures and gas residence times. The durability of the best sorbent formulation identified in the screening tests is evaluated in ``long-term`` durability tests conducted at the optimum operating conditions. This includes testing the sorbent in pellet and granular forms in packed- and fluidized-bed reactors. During this quarter, twenty one copper chromite-based sorbent formulations were prepared. Two sorbent formulations that have acceptable crush strength, designated as CuCr-10 and CuCr-21, were tested over 5 and 6 cycles respectively. The results indicate that both sorbents are reactive toward H{sub 2}S at 650{degrees}C and that the reactivity of the sorbents are relatively constant over the first 5 to 6 cycles. The H{sub 2}S prebreakthrough concentrations were generally about 20 to 30 ppm, making them suitable for IGCC application.

  4. EVALUATION OF FGD DRY INJECTION SORBENTS AND ADDITIVES - VOLUME 2 - PILOT PLANT EVALUATION OF HIGH REACTIVITY SORBENTS

    EPA Science Inventory

    The report describes a mini-pilot test program to investigate potential new sorbents and processes for dry SO2 removal. Initial tests showed that the 85 cu m/h pilot plant could be used successfully to evaluate both spray dryer and dry injection processes using traditional calciu...

  5. DEVELOPMENT OF A HYDROGEN MORDENITE SORBENT FOR THE CAPTURE OF KRYPTON FROM USED NUCLEAR FUEL REPROCESSING OFF-GAS STREAMS

    SciTech Connect

    Mitchell Greenhalgh; Troy G. Garn; Jack D. Law

    2014-04-01

    A novel new sorbent for the separation of krypton from off-gas streams resulting from the reprocessing of used nuclear fuel has been developed and evaluated. A hydrogen mordenite powder was successfully incorporated into a macroporous polymer binder and formed into spherical beads. The engineered form sorbent retained the characteristic surface area and microporosity indicative of mordenite powder. The sorbent was evaluated for krypton adsorption capacities utilizing thermal swing operations achieving capacities of 100 mmol of krypton per kilogram of sorbent at a temperature of 191 K. A krypton adsorption isotherm was also obtained at 191 K with varying krypton feed gas concentrations. Adsorption/desorption cycling effects were also evaluated with results indicating that the sorbent experienced no decrease in krypton capacity throughout testing.

  6. Evaluation of Carbon Dioxide Capture From Existing Coal Fired Plants by Hybrid Sorption Using Solid Sorbents

    SciTech Connect

    Benson, Steven; Srinivasachar, Srivats; Laudal, Daniel; Browers, Bruce

    2014-12-31

    A novel hybrid solid sorbent technology for CO₂ capture and separation from coal combustion-derived flue gas was evaluated. The technology – Capture of CO₂ by Hybrid Sorption (CACHYS™) – is a solid sorbent technology based on the following ideas: 1) reduction of energy for sorbent regeneration, 2) utilization of novel process chemistry, 3) contactor conditions that minimize sorbent-CO₂ heat of reaction and promote fast CO₂ capture, and 4) low-cost method of heat management. This report provides key information developed during the course of the project that includes sorbent performance, energy for sorbent regeneration, physical properties of the sorbent, the integration of process components, sizing of equipment, and overall capital and operational cost of the integrated CACHYS™ system. Seven sorbent formulations were prepared and evaluated at the lab-scale for energy requirements and CO₂ capture performance. Sorbent heat of regeneration ranged from 30-80 kJ/mol CO₂ and was found to be dependent on process conditions. Two sorbent formulations (designated HCK-4 & HCK-7) were down-selected for additional fixed-bed testing. Additional testing involved subjecting the sorbents to 100 continuous cycles in the fixed-bed reactor to determine performance as a function of time. The working capacity achieved for HCK-4 sorbent ranged from 5.5-8.0 g CO₂/100 g sorbent, while the HCK-7 typically ranged from 8.0-10.0 g CO₂/100 g sorbent. Overall, there was no deterioration in capacity with continuous cycling for either sorbent. The CACHYS™ bench-scale testing system designed and fabricated under this award consists of a dual circulating fluidized-bed adsorber and a moving-bed regenerator. The system takes a flue gas slipstream from the University of North Dakota’s coal-fired steam plant. Prior to being sent to the adsorber, the flue gas is scrubbed to remove SO₂ and particulate. During parametric testing of the adsorber, CO₂ capture achieved using

  7. Evaluation of inorganic sorbent treatment for LWR coolant process streams

    SciTech Connect

    Roddy, J.W.

    1984-03-01

    This report presents results of a survey of the literature and of experience at selected nuclear installations to provide information on the feasibility of replacing organic ion exchangers with inorganic sorbents at light-water-cooled nuclear power plants. Radioactive contents of the various streams in boiling water reactors and pressurized water reactors were examined. In addition, the methods and performances of current methods used for controlling water quality at these plants were evaluated. The study also includes a brief review of the physical and chemical properties of selected inorganic sorbents. Some attributes of inorganic sorbents would be useful in processing light water reactor (LWR) streams. The inorganic resins are highly resistant to damage from ionizing radiation, and their exchange capacities are generally equivalent to those of organic ion exchangers. However, they are more limited in application, and there are problems with physical integrity, especially in acidic solutions. Research is also needed in the areas of selectivity and anion removal before inorganic sorbents can be considered as replacements for the synthetic organic resins presently used in LWRs. 11 figures, 14 tables.

  8. Evaluation of Dry Sorbent Injection Technology for Pre-Combustion CO{sub 2} Capture

    SciTech Connect

    Richardson, Carl; Steen, William; Triana, Eugenio; Machalek, Thomas; Davila, Jenny; Schmit, Claire; Wang, Andrew; Temple, Brian; Lu, Yongqi; Lu, Hong; Zhang, Luzheng; Ruhter, David; Rostam-Abadi, Massoud; Sayyah, Maryam; Ito, Brandon; Suslick, Kenneth

    2013-09-30

    This document summarizes the work performed on Cooperative Agreement DE-FE0000465, “Evaluation of Dry Sorbent Technology for Pre-Combustion CO{sub 2} Capture,” during the period of performance of January 1, 2010 through September 30, 2013. This project involves the development of a novel technology that combines a dry sorbent-based carbon capture process with the water-gas-shift reaction for separating CO{sub 2} from syngas. The project objectives were to model, develop, synthesize and screen sorbents for CO{sub 2} capture from gasified coal streams. The project was funded by the DOE National Energy Technology Laboratory with URS as the prime contractor. Illinois Clean Coal Institute and The University of Illinois Urbana-Champaign were project co-funders. The objectives of this project were to identify and evaluate sorbent materials and concepts that were suitable for capturing carbon dioxide (CO{sub 2}) from warm/hot water-gas-shift (WGS) systems under conditions that minimize energy penalties and provide continuous gas flow to advanced synthesis gas combustion and processing systems. Objectives included identifying and evaluating sorbents that efficiently capture CO{sub 2} from a gas stream containing CO{sub 2}, carbon monoxide (CO), and hydrogen (H{sub 2}) at temperatures as high as 650 °C and pressures of 400-600 psi. After capturing the CO{sub 2}, the sorbents would ideally be regenerated using steam, or other condensable purge vapors. Results from the adsorption and regeneration testing were used to determine an optimal design scheme for a sorbent enhanced water gas shift (SEWGS) process and evaluate the technical and economic viability of the dry sorbent approach for CO{sub 2} capture. Project work included computational modeling, which was performed to identify key sorbent properties for the SEWGS process. Thermodynamic modeling was used to identify optimal physical properties for sorbents and helped down-select from the universe of possible sorbent

  9. Development of a Rapid Cycling CO2 and H2O Removal Sorbent

    NASA Technical Reports Server (NTRS)

    Alptekin, Gokhan; Cates, Matthew; Bernal, Casey; Dubovik, Margarita; Paul, Heather L.

    2007-01-01

    The National Aeronautics and Space Administration (NASA) planned future missions set stringent demands on the design of the Portable Life Support System (PLSS), requiring dramatic reductions in weight, decreased reliance on supplies and greater flexibility on the types of missions. Use of regenerable systems that reduce weight and volume of the Extravehicular Mobility Unit (EMU) is of critical importance to NASA, both for low orbit operations and for long duration manned missions. The carbon dioxide and humidity control unit in the existing PLSS design is relatively large, since it has to remove and store eight hours worth of carbon dioxide (CO2). If the sorbent regeneration can be carried out during the Extravehicular Activity (EVA) with a relatively high regeneration frequency, the size of the sorbent canister and weight can be significantly reduced. TDA Research, Inc. is developing compact, regenerable sorbent materials to control CO2 and humidity in the space suit ventilation loop. The sorbent can be regenerated using space vacuum during the EVA, eliminating all CO2 and humidity duration-limiting elements in the life support system. The material also has applications in other areas of space exploration including long duration exploration missions requiring regenerable technologies and possibly the Crew Exploration Vehicle (CEV) spacecraft. This paper summarizes the results of the sorbent development, testing, and evaluation efforts to date.

  10. Evaluation of Sorbent Injection for Mercury Control

    SciTech Connect

    Sharon Sjostrom

    2008-06-30

    ADA-ES, Inc., with support from DOE/NETL, EPRI, and industry partners, studied mercury control options at six coal-fired power plants. The overall objective of the this test program was to evaluate the capabilities of activated carbon injection at six plants: Sunflower Electric's Holcomb Station Unit 1, AmerenUE's Meramec Station Unit 2, Missouri Basin Power Project's Laramie River Station Unit 3, Detroit Edison's Monroe Power Plant Unit 4, American Electric Power's Conesville Station Unit 6, and Labadie Power Plant Unit 2. These plants have configurations that together represent 78% of the existing coal-fired generation plants. The financial goals for the program established by DOE/NETL were to reduce the uncontrolled mercury emissions by 50 to 70% at a cost 25 to 50% lower than the target established by DOE of $60,000 per pound of mercury removed. Results from testing at Holcomb, Laramie, Meramec, Labadie, and Monroe indicate the DOE goal was successfully achieved. However, further improvements for plants with conditions similar to Conesville are recommended that would improve both mercury removal performance and economics.

  11. Development of Novel Sorbents for Uranium Extraction from Seawater

    SciTech Connect

    Lin, Wenbin; Taylor-Pashow, Kathryn

    2014-01-08

    As the uranium resource in terrestrial ores is limited, it is difficult to ensure a long-term sustainable nuclear energy technology. The oceans contain approximately 4.5 billion tons of uranium, which is one thousand times the amount of uranium in terrestrial ores. Development of technologies to recover the uranium from seawater would greatly improve the uranium resource availability, sustaining the fuel supply for nuclear energy. Several methods have been previously evaluated including solvent extraction, ion exchange, flotation, biomass collection, and adsorption; however, none have been found to be suitable for reasons such as cost effectiveness, long term stability, and selectivity. Recent research has focused on the amidoxime functional group as a promising candidate for uranium sorption. Polymer beads and fibers have been functionalized with amidoxime functional groups, and uranium adsorption capacities as high as 1.5 g U/kg adsorbent have recently been reported with these types of materials. As uranium concentration in seawater is only ~3 ppb, great improvements to uranium collection systems must be made in order to make uranium extraction from seawater economically feasible. This proposed research intends to develop transformative technologies for economic uranium extraction from seawater. The Lin group will design advanced porous supports by taking advantage of recent breakthroughs in nanoscience and nanotechnology and incorporate high densities of well-designed chelators into such nanoporous supports to allow selective and efficient binding of uranyl ions from seawater. Several classes of nanoporous materials, including mesoporous silica nanoparticles (MSNs), mesoporous carbon nanoparticles (MCNs), meta-organic frameworks (MOFs), and covalent-organic frameworks (COFs), will be synthesized. Selective uranium-binding liagnds such as amidoxime will be incorporated into the nanoporous materials to afford a new generation of sorbent materials that will be

  12. Development of a sorbent-based technology for control of mercury in flue gas

    SciTech Connect

    Wu, Jiann M.; Huang, Hann S.; Livengood, C.D.

    1996-03-01

    This paper presents results of research being, conducted at Argonne National Laboratory on the capture of elemental mercury in simulated flue gases by using dry sorbents. Experimental results from investigation of various sorbents and chemical additives for mercury control are reported. Of the sorbents investigated thus far, an activited-carbon-based sorbent impregnated with about 15% (by weight) of sulfur compound provided the best results. The key parameters affecting mercury control efficiency in a fixed-bed reactor, such as reactor loading, reactor temperature, sorbent size distribution, etc., were also studied, and the results ire presented. In addition to activated-carbon-based sorbents, a non-carbon-based sorbent that uses an inactive substrate treated with active chemicals is being developed. Preliminary, experimental results for mercury removal by this newly developed sorbent are presented.

  13. Development of charcoal sorbents for helium cryopumping

    SciTech Connect

    Sedgley, D.W.; Tobin, A.G.

    1985-09-30

    Improved methods for cryopumping helium were developed for application to fusion reactors where high helium generation rates are expected. This study period evaluated charcoal particle size, bonding agent type and thickness, and substrate thickness. The optimum combination of charcoal, bond, and substrate was used to form a scaled-up panel for evaluation in the Tritium Systems Test Assembly (TSTA) at Los Alamos. The optimum combination is a 12 x 30 mesh coconut charcoal attached to a 0.48 cm thick copper substrate by a 0.015 cm thick silver phosphorus copper braze. A copper cement bond for attaching charcoal to a substrate was identified and tested. Helium pumping performance of this combination was comparable to that of the charcoal braze system. Environmental tests showed the charcoal's susceptibility to vacuum chamber contamination. Performance degradation followed exposure of ambient temperature charcoal to a vacuum for prolonged periods. Maintaining a liquid nitrogen-cooled shield between the charcoal and the source of contamination prevented this degradation. A combination of bake-out and LN shielding effected recovery of degraded performance.

  14. EVALUATION OF SOLID SORBENTS AS A RETROFIT TECHNOLOGY FOR CO2 CAPTURE FROM COAL-FIRED POWER PLANTS

    SciTech Connect

    Holly Krutka; Sharon Sjostrom

    2011-07-31

    Through a U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) funded cooperative agreement DE-NT0005649, ADA Environmental Solutions (ADA) has begun evaluating the use of solid sorbents for CO{sub 2} capture. The project objective was to address the viability and accelerate development of a solid-based CO{sub 2} capture technology. To meet this objective, initial evaluations of sorbents and the process/equipment were completed. First the sorbents were evaluated using a temperature swing adsorption process at the laboratory scale in a fixed-bed apparatus. A slipstream reactor designed to treat flue gas produced by coal-fired generation of nominally 1 kWe was designed and constructed, which was used to evaluate the most promising materials on a more meaningful scale using actual flue gas. In a concurrent effort, commercial-scale processes and equipment options were also evaluated for their applicability to sorbent-based CO{sub 2} capture. A cost analysis was completed that can be used to direct future technology development efforts. ADA completed an extensive sorbent screening program funded primarily through this project, DOE NETL cooperative agreement DE-NT0005649, with support from the Electric Power Research Institute (EPRI) and other industry participants. Laboratory screening tests were completed on simulated and actual flue gas using simulated flue gas and an automated fixed bed system. The following types and quantities of sorbents were evaluated: 87 supported amines; 31 carbon based materials; 6 zeolites; 7 supported carbonates (evaluated under separate funding); and 10 hydrotalcites. Sorbent evaluations were conducted to characterize materials and down-select promising candidates for further testing at the slipstream scale. More than half of the materials evaluated during this program were supported amines. Based on the laboratory screening four supported amine sorbents were selected for evaluation at the 1 kW scale at two different

  15. Evaluation of charcoal sorbents for helium cryopumping in fusion reactors

    SciTech Connect

    Tobin, A.G.; Sedgley, D.W.; Batzer, T.H.; Call, W.R.

    1987-01-01

    Improved methods for cryopumping helium were developed for application to fusion reactors where high helium generation rates are expected. In this study, small coconut charcoal granules were utilized as the sorbent, and braze alloys and low temperature curing cements were used as the bonding agents for attachment to a copper support structure. Problems of scale-up of the bonding agent to a 40 cm diam panel were also investigated. Our results indicate that acceptable helium pumping performance of braze bonded and cement bonded charcoals can be achieved over the range of operating conditions expected in fusion reactors.

  16. Development of novel copper-based sorbents for hot-gas cleanup

    SciTech Connect

    Abbasian, J.

    1991-01-01

    The objective of this investigation is to evaluate several novel copper-based binary oxides for their suitability as regenerable sorbents for hot gas cleanup application in the temperature range of 650{degree} to 850{degree}C (1200{degree}--1550{degree}F). To achieve this objective, several novel copper-based binary oxide sorbents will be prepared. Experimental tests will be conducted at ambient pressure to determine the stability, sulfidation capacity, regenerability, and sulfidation kinetics of the novel sorbents. Tests will also be conducted at high pressure for the determination of the sulfidation reactivity, regenerability, and durability of the sorbents. The attrition characteristics of the sorbents will also be determined.

  17. Evaluation of nonwoven polypropylene oil sorbents in marine oil-spill recovery.

    PubMed

    Wei, Q F; Mather, R R; Fotheringham, A F; Yang, R D

    2003-06-01

    Mechanical recovery of oil by oil sorbents is one of the most important countermeasures in marine oil-spill response. Polypropylene is the ideal material for marine oil-spill recovery due to its low density, low water uptake and excellent physical and chemical resistance. Different forms of polypropylene nonwoven sorbents were evaluated in this study in terms of initial oil-sorption capacities and oil-retention properties. The investigation revealed that the fibre diameter, sorbent porosity and oil property are the most important factors in the oil-sorption performance of polypropylene nonwoven sorbents.

  18. Development of sorbents for high-temperature desulfurization in moving-bed systems

    SciTech Connect

    Ayala, R.E.; Chuck, T.; Gal, E.; Gupta, R.P.

    1994-10-01

    The objective of the option 3 program within this contract is to develop chemically reactive and mechanically durable mixed-metal oxide sorbent formulations that are suitable for moving-bed, high-temperature, desulfurization of coal gas. One optimum formulation will be evaluated in a pressurized 50-cycle bench-scale test. Work on zinc titanate formulations was initiated under the option 2 program and is continued under the present option 3 program along with testing of other mixed-metal oxides. One of the major limitations for large-scale use of mixed-metal oxides is the observed weakening and physical deterioration of the pellet and spalling during repetitive use in cycles of absorption and regeneration. A need exists to determine best operating conditions that minimize sulfate formation and prevent mechanical degradation. Results from materials tests on 5 zinc-based sorbents are given.

  19. Evaluation of Solid Sorbents As A Retrofit Technology for CO{sub 2} Capture from Coal-Fired Power Plants

    SciTech Connect

    Krutka, Holly; Sjostrom, Sharon

    2011-07-31

    Through a U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) funded cooperative agreement DE-NT0005649, ADA Environmental Solutions (ADA) has begun evaluating the use of solid sorbents for CO{sub 2} capture. The project objective was to address the viability and accelerate development of a solid-based CO{sub 2} capture technology. To meet this objective, initial evaluations of sorbents and the process / equipment were completed. First the sorbents were evaluated using a temperature swing adsorption process at the laboratory scale in a fixed-bed apparatus. A slipstream reactor designed to treat flue gas produced by coal-fired generation of nominally 1 kWe was designed and constructed, which was used to evaluate the most promising materials on a more meaningful scale using actual flue gas. In a concurrent effort, commercial-scale processes and equipment options were also evaluated for their applicability to sorbent-based CO{sub 2} capture. A cost analysis was completed that can be used to direct future technology development efforts. ADA completed an extensive sorbent screening program funded primarily through this project, DOE NETL cooperative agreement DE-NT0005649, with support from the Electric Power Research Institute (EPRI) and other industry participants. Laboratory screening tests were completed on simulated and actual flue gas using simulated flue gas and an automated fixed bed system. The following types and quantities of sorbents were evaluated: 87 supported amines, 31 carbon based materials, 6 zeolites, 7 supported carbonates (evaluated under separate funding), 10 hydrotalcites. Sorbent evaluations were conducted to characterize materials and down-select promising candidates for further testing at the slipstream scale. More than half of the materials evaluated during this program were supported amines. Based on the laboratory screening four supported amine sorbents were selected for evaluation at the 1 kW scale at two different

  20. EVALUATION OF CARBON DIOXIDE CAPTURE FROM EXISTING COAL FIRED PLANTS BY HYBRID SORPTION USING SOLID SORBENTS

    SciTech Connect

    Benson, Steven; Browers, Bruce; Srinivasachar, Srivats; Laudal, Daniel

    2014-12-31

    Under contract DE-FE0007603, the University of North Dakota conducted the project Evaluation of Carbon Dioxide Capture from Existing Coal Fired Plants by Hybrid Sorption Using Solid Sorbents. As an important element of this effort, a Technical and Economic Feasibility Study was conducted by Barr Engineering Co. (Barr) in association with the University of North Dakota. The assessment developed a process flow diagram, major equipment list, heat balances for the SCPC power plant, capital cost estimate, operating cost estimate, levelized cost of electricity, cost of CO2 capture ($/ton) and three sensitivity cases for the CACHYS™ process.

  1. Engineered sorbent barrier screening studies

    SciTech Connect

    Freeman, H.D.; Buelt, J.L.

    1985-08-01

    The objective of the Engineered Sorbent Barrier Program is to identify new and cost-effective technology for restricting the migration of radionuclides from low-level waste sites. The primary emphasis is to identify and evaluate sorbent materials as engineered barriers that will prevent radionuclide migration and yet allow moisture to pass. Screening studies have been completed to identify sorbent materials for cesium, cobalt, and strontium. The sorbent materials were selected based on criteria developed for this program and the empirical results of screening studies. The results of the study made it apparent that no single sorbent materials is effective for all radionuclides considered. Therefore, four composite sorbent barriers were identified for further evaluation in 0.6-m diameter columns. The large columns more accurately represent field conditions, generate permeability data, and enhance detectability of radionuclides in the leachate passing through the sorbent barriers. The four sorbent barriers include composites of activated charcoal, greensand, A-51 zeolite, and red pottery clay. Future studies will concentrate on completing the effectiveness evaluations with the large columns and identifying a more cost-effective sorbent material for strontium. 6 refs., 4 figs., 4 tabs.

  2. Development of a Microwave Regenerative Sorbent-Based Hydrogen Purifier

    NASA Technical Reports Server (NTRS)

    Wheeler, Richard R., Jr.; Dewberry, Ross H.; McCurry, Bryan D.; Abney, Morgan B.; Greenwood, Zachary W.

    2016-01-01

    This paper describes the design and fabrication of a Microwave Regenerative Sorbent-based Hydrogen Purifier (MRSHP). This unique microwave powered technology was developed for the purification of a hydrogen stream produced by the Plasma Pyrolysis Assembly (PPA). The PPA is a hydrogen recovery (from methane) post processor for NASA's Sabatier-based carbon dioxide reduction process. Embodied in the Carbon dioxide Reduction Assembly (CRA), currently aboard the International Space Station (ISS), the Sabatier reaction employs hydrogen to catalytically recover oxygen, in the form of water, from respiratory carbon dioxide produced by the crew. This same approach is base-lined for future service in the Air Revitalization system on extended missions into deep space where resupply is not practical. Accordingly, manned exploration to Mars may only become feasible with further closure of the air loop as afforded by the greater hydrogen recovery permitted by the PPA with subsequent hydrogen purification. By utilizing the well-known high sorbate loading capacity of molecular sieve 13x, coupled with microwave dielectric heating phenomenon, MRSHP technology is employed as a regenerative filter for a contaminated hydrogen gas stream. By design, freshly regenerated molecular sieve 13x contained in the MRSHP will remove contaminants from the effluent of a 1-CM scale PPA for several hours prior to breakthrough. By reversing flow and pulling a relative vacuum the MRSHP prototype then uses 2.45 GHz microwave power, applied through a novel coaxial antenna array, to rapidly heat the sorbent bed and drive off the contaminants in a short duration vacuum/thermal contaminant desorption step. Finally, following rapid cooling via room temperature cold plates, the MRSHP is again ready to serve as a hydrogen filter.

  3. Efficient separations and processing crosscutting program: Develop and test sorbents

    SciTech Connect

    Bray, L.A.

    1995-09-01

    This report summarizes work performed during FY 1995 under the task {open_quotes}Develop and Test Sorbents,{close_quotes} the purpose of which is to develop high-capacity, selective solid extractants to recover cesium, strontium, and technetium from nuclear wastes. This work is being done for the Efficient Separations and Processing Crosscutting Program (ESP), operated by the U.S. Department of Energy`s Office of Environmental Management`s Office of Technology Development. The task is under the direction of staff at Pacific Northwest Laboratory (PNL) with key participation from industrial and university staff at 3M, St. Paul, Minnesota; IBC Advanced Technologies, Inc., American Forks, Utah; AlliedSignal, Inc., Des Plaines, Illinois, and Texas A&M University, College Station, Texas. 3M and IBC are responsible for ligand and membrane technology development; AlliedSignal and Texas A&M are developing sodium titanate powders; and PNL is testing the materials developed by the industry/university team members. Major accomplishments for FY 1995 are summarized in this report.

  4. DEVELOPMENT OF A CATALYST/SORBENT FOR METHANE REFORMING

    SciTech Connect

    B.H. Shanks; T.D. Wheelock; Justinus A. Satrio; Timothy Diehl; Brigitte Vollmer

    2004-09-27

    This work has led to the initial development of a very promising material that has the potential to greatly simplify hydrocarbon reforming for the production of hydrogen and to improve the overall efficiency and economics of the process. This material, which was derived from an advanced calcium-based sorbent, was composed of core-in-shell pellets such that each pellet consisted of a CaO core and an alumina-based shell. By incorporating a nickel catalyst in the shell, a combined catalyst and sorbent was prepared to facilitate the reaction of hydrocarbons with steam. It was shown that this material not only catalyzes the reactions of methane and propane with steam, it also absorbs CO{sub 2} simultaneously, and thereby separates the principal reaction products, H{sub 2} and CO{sub 2}. Furthermore, the absorption of CO{sub 2} permits the water gas shift reaction to proceed much further towards completion at temperatures where otherwise it would be limited severely by thermodynamic equilibrium. Therefore, an additional water gas shift reaction step would not be required to achieve low concentrations of CO. In a laboratory test of methane reforming at 600 C and 1 atm it was possible to produce a gaseous product containing 96 mole% H{sub 2} (dry basis) while also achieving a H{sub 2} yield of 95%. Methane reforming under these conditions without CO{sub 2} absorption provided a H{sub 2} concentration of 75 mole% and yield of 82%. Similar results were achieved in a test of propane reforming at 560 C and 1 atm which produced a product containing 96 mole% H{sub 2} while CO{sub 2} was being absorbed but which contained only 69 mole% H{sub 2} while CO{sub 2} was not being absorbed. These results were achieved with an improved catalyst support that was developed by replacing a portion of the {alpha}-alumina in the original shell material with {gamma}-alumina having a much greater surface area. This replacement had the unfortunate consequence of reducing the overall compressive

  5. Development of a Catalyst/Sorbent for Methane Reforming

    SciTech Connect

    B.H. Shans; T.D. Wheelock; Justinus Satrio; Karl Albrecht; Tanya Harris Janine Keeley; Ben Silva; Aaron Shell; Molly Lohry; Zachary Beversdorf

    2008-12-31

    This project led to the further development of a combined catalyst and sorbent for improving the process technology required for converting CH{sub 4} and/or CO into H{sub 2} while simultaneously separating the CO{sub 2} byproduct all in a single step. The new material is in the form of core-in-shell pellets such that each pellet consists of a CaO core surrounded by an alumina-based shell capable of supporting a Ni catalyst. The Ni is capable of catalyzing the reactions of steam with CH{sub 4} or CO to produce H{sub 2} and CO{sub 2}, whereas the CaO is capable of absorbing the CO{sub 2} as it is produced. The absorption of CO{sub 2} eliminates the reaction inhibiting effects of CO{sub 2} and provides a means for recovering the CO{sub 2} in a useful form. The present work showed that the lifecycle performance of the sorbent can be improved either by incorporating a specific amount of MgO in the material or by calcining CaO derived from limestone at 1100 C for an extended period. It also showed how to prepare a strong shell material with a large surface area required for supporting an active Ni catalyst. The method combines graded particles of {alpha}-alumina with noncrystalline alumina having a large specific surface area together with a strength promoting additive followed by controlled calcination. Two different additives produced good results: 3 {micro}m limestone and lanthanum nitrate which were converted to their respective oxides upon calcination. The oxides partially reacted with the alumina to form aluminates which probably accounted for the strength enhancing properties of the additives. The use of lanthanum made it possible to calcine the shell material at a lower temperature, which was less detrimental to the surface area, but still capable of producing a strong shell. Core-in-shell pellets made with the improved shell materials and impregnated with a Ni catalyst were used for steam reforming CH{sub 4} at different temperatures and pressures. Under all

  6. Advanced sorbent development program. Annual report, November 1, 1994--November 30, 1995

    SciTech Connect

    1995-12-31

    The overall objective of this program is to develop regenerable sorbents for hydrogen sulfide removal from coal-derived fuel gases in the temperature range 343--538 C. Two categories of reactor configurations are being considered: fixed-bed/moving-bed reactors and fluidized-bed (bubbling and circulating) reactors. In addition, a cost assessment and a market plan for large-scale fabrication of sorbents will be developed. As an optional task, a long-term bench-scale testing (100 cycles) of the best fixed-bed/moving-bed and fluidized-bed sorbents will be conducted. The sorbents will have chemical characteristics that permit cyclic regeneration over many cycles without a drastic loss of activity. They must also have physical characteristics that are compatible with the selected reactor, e.g., fixed vs fluidized bed, and which remain acceptable during absorption and regeneration. The sorbents must be capable of reducing the hydrogen sulfide level in the fuel gas to less than 20 ppmv in the specified temperature range and pressures in the range of 1 to 20 atmospheres. The proposed program is divided into several tasks: NEPA Report; Sorbent Preparation; Provision of Bench Unit; Bench Testing; Sorbent Cost Assessment; Topical Report; Market Plan; and Long-Term Testing. Progress on each of these is described.

  7. Development of novel copper-based sorbents for hot-gas cleanup. Technical report, September 1--November 30, 1991

    SciTech Connect

    Abbasian, J.

    1991-12-31

    The objective of this investigation is to evaluate several novel copper-based binary oxides for their suitability as regenerable sorbents for hot gas cleanup application in the temperature range of 650{degree} to 850{degree}C (1200{degree}--1550{degree}F). To achieve this objective, several novel copper-based binary oxide sorbents will be prepared. Experimental tests will be conducted at ambient pressure to determine the stability, sulfidation capacity, regenerability, and sulfidation kinetics of the novel sorbents. Tests will also be conducted at high pressure for the determination of the sulfidation reactivity, regenerability, and durability of the sorbents. The attrition characteristics of the sorbents will also be determined.

  8. Evaluation of Type I cement sorbent slurries in the U.C. pilot spray dryer facility. Final report, November 1, 1994--February 28, 1996

    SciTech Connect

    Keener, T.C.; Khang, S.J.

    1996-07-31

    This research was focused on evaluating hydrated cement sorbents in the U. C. pilot spray dryer. The main goal of this work was to determine the hydration conditions resulting in reactive hydrated cement sorbents. Hydration of cement was achieved by stirring or by grinding in a ball mill at either room temperature or elevated temperatures. Also, the effects of several additives were studied. Additives investigated include calcium chloride, natural diatomite, calcined diatomaceous earth, and fumed silica. The performance of these sorbents was compared with conventional slaked lime. Further, the specific surface area and pore volume of the dried SDA sorbents were measured and compared to reactivity. Bench-scale tests were performed to obtain a more detailed picture of the development of the aforementioned physical properties as a function of hydration time.

  9. Environmentally Friendly Method: Development and Application to Carbon Aerogel as Sorbent for Solid-Phase Extraction.

    PubMed

    Dong, Sheying; Huang, Guiqi; Su, Meiling; Huang, Tinglin

    2015-10-14

    We developed two simple, fast, and environmentally friendly methods using carbon aerogel (CA) and magnetic CA (mCA) materials as sorbents for micro-solid-phase extraction (μ-SPE) and magnetic solid-phase extraction (MSPE) techniques. The material performances such as adsorption isotherm, adsorption kinetics, and specific surface area were discussed by N2 adsorption-desorption isotherm measurements, ultraviolet and visible (UV-vis) spectrophotometry, scanning electron microscopy (SEM), and high resolution transmission electron microscopy (HR-TEM). The experimental results proved that the heterogeneities of CA and mCA were well modeled with the Freundlich isotherm model, and the sorption process well followed the pseudo-second-order rate equation. Moreover, plant growth regulators (PGRs) such as kinetin (6-KT), 6-benzylaminopurine (6-BA), 2,4-dichlorophenoxyacetic acid (2,4-D), and uniconazole (UN) in a reservoir raw water sample were selected as the evaluation of applicability for the proposed μ-SPE and MSPE techniques using high performance liquid chromatography (HPLC). The experimental conditions of two methods such as the amount of sorbent, extraction time, pH, salt concentration, and desorption conditions were studied. Under the optimized conditions, two extraction methods provided high recoveries (89-103%), low the limits of detection (LODs) (0.01-0.2 μg L(-1)), and satisfactory analytical features in terms of precision (relative standard deviation, RSD, 1.7-5.1%, n=3). This work demonstrates the feasibility and the potential of CA and mCA materials as sorbents for μ-SPE and MSPE techniques. Besides, it also could serve as a basis for future development of other functional CAs in pretreatment technology and make them valuable for analysis of pollutants in environmental applications.

  10. Selective determination of cocaine and its metabolite benzoylecgonine in environmental samples by newly developed sorbent materials.

    PubMed

    Bujak, Renata; Gadzała-Kopciuch, Renata; Nowaczyk, Alicja; Raczak-Gutknecht, Joanna; Kordalewska, Marta; Struck-Lewicka, Wiktoria; Markuszewski, Michał J; Buszewski, Bogusław

    2016-01-01

    Sewage epidemiology, as compared to crime statistics, health, medical reports or population surveys, is becoming the most objective and realistic approach to estimate drug consumption and trends in local communities. In this study we proposed newly synthesized sorbent materials for selective extraction of cocaine and benzoylecgonine from wastewater samples. The molecular modeling calculations were conducted to provide the choice of proper template and functional monomer for synthesis of extraction materials. The physicochemical properties of synthesized sorbents were studied using various techniques. The newly developed sorbent materials were applied for selective extraction of cocaine and benzoylecgonine from wastewater samples collected from different wastewater treatment plants in Poland. The obtained recoveries values in wastewater samples were 83.6(±7.1)% and 72.1(±4.8)%, for cocaine and benzoylecgonine, respectively. The newly developed sorbents comprise an alternative to conventional ones, which are not entirely suitable for highly efficient purification of environmental samples due to the presence of contaminants.

  11. Sorbent Structural Impacts Due to Humidity on Carbon Dioxide Removal Sorbents for Advanced Exploration Systems

    NASA Technical Reports Server (NTRS)

    Watson, David; Knox, James C.; West, Phillip; Stanley, Christine M.; Bush, Richard

    2015-01-01

    The Life Support Systems Project (LSSP) under the Advanced Exploration Systems (AES) program builds upon the work performed under the AES Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project focusing on the numerous technology development areas. The CO2 removal and associated air drying development efforts are focused on improving the current state-of-the-art system on the International Space Station (ISS) utilizing fixed beds of sorbent pellets by seeking more robust pelletized sorbents, evaluating structured sorbents, and examining alternate bed configurations to improve system efficiency and reliability. A component of the CO2 removal effort encompasses structural stability testing of existing and emerging sorbents. Testing will be performed on dry sorbents and sorbents that have been conditioned to three humidity levels. This paper describes the sorbent structural stability screening efforts in support of the LSS Project within the AES Program.

  12. Development of Novel Carbon Sorbents for CO{sub 2} Capture

    SciTech Connect

    Krishnan, Gopala; Hornbostel, Marc; Bao, Jianer; Perez, Jordi; Nagar, Anoop; Sanjurjo, Angel

    2013-11-30

    An innovative, low-cost, and low-energy-consuming carbon dioxide (CO{sub 2}) capture technology was developed, based on CO{sub 2}adsorption on a high-capacity and durable carbon sorbent. This report describes the (1) performance of the concept on a bench-scale system; (2) results of parametric tests to determine the optimum operating conditions; (3) results of the testing with a flue gas from coal-fired boilers; and (4) evaluation of the technical and economic viability of the technology. The process uses a falling bed of carbon sorbent microbeads to separate the flue gas into two streams: a CO{sub 2} -lean flue gas stream from which > 90% of the CP{sub 2} is removed and a pure stream of CO{sub 2} that is ready for compression and sequestration. The carbo sorbent microbeads have several unique properties such as high CO{sub 2} capacity, low heat of adsorption and desorption (25 to 28 kJ/mole), mechanically robust, and rapid adsorption and desorption rates. The capture of CO{sub 2} from the flue gas is performed at near ambient temperatures in whic the sorbent microbeads flow down by gravity counter-current with the up-flow of the flue gas. The adsorbed CO{sub 2} is stripped by heating the CO{sub 2}-loaded sorbent to - 100°C, in contact with low-pressure (- 5 psig) steam in a section at the bottom of the adsorber. The regenerated sorben is dehydrated of adsorbed moisture, cooled, and lifted back to the adsorber. The CO{sub 2} from the desorber is essentially pure and can be dehydrated, compressed, and transported to a sequestration site. Bench-scale tests using a simulated flue gas showed that the integrated system can be operated to provide > 90% CO{sub 2} capture from a 15% CO{sub 2} stream in the adsorber and produce > 98% CO{sub 2} at the outlet of the stripper. Long-term tests ( 1,000 cycles) showed that the system can be operated reliably without sorbent agglomeration or attrition. The bench-scale reactor was also operated using a flue gas stream from a coal

  13. Development of natural sorbent based micro-solid-phase extraction for determination of phthalate esters in milk samples.

    PubMed

    Sajid, Muhammad; Basheer, Chanbasha; Alsharaa, Abdulnaser; Narasimhan, Kothandaraman; Buhmeida, Abdelbaset; Al Qahtani, Mohammed; Al-Ahwal, Mahmoud Shaheen

    2016-06-14

    In the present study, a natural sorbent based micro-solid phase extraction (μ-SPE) was developed for determination of phthalate esters in milk samples. For the first time, an efficient and cost effective natural material (seed powder of Moringa oleifera) was employed as sorbent in μ-SPE. The sorbent was found to be naturally enriched with variety of functional groups and having a network of interconnected fibers. This method of extraction integrates different steps such as removal of proteins and fatty stuff, extraction and pre-concentration of target analytes into a single step. Thirteen phthalate esters were selected as target compounds for the development and evaluation of method. Some key parameters affecting the extraction efficiency were optimized, including selection of membrane, selection and amount of sorbent, extraction time, desorption solvent, volume of desorption solvent, desorption time and effect of salt addition. Under the optimum conditions, very good linearity was achieved for all the analytes with coefficient of determinations (R(2)) ranging between 0.9768 and 0.9977. The limits of detection ranged from 0.01 to 1.2 μg L(-1). Proposed method showed satisfactory reproducibility with relative standard deviations ranging from 3.6% to 10.2% (n = 7). Finally, the developed method was applied to tetra pack and bottled milk samples for the determination of phthalate esters. The performance of natural sorbent based μ-SPE was better or comparable to the methods reported in the literature. PMID:27181642

  14. BENCH-SCALE EVALUATION OF CALCIUM SORBENTS FOR ACID GAS EMISSION CONTROL

    EPA Science Inventory

    Calcium sorbents for acid gas emission control were evaluated for effectiveness in removing SO2/HCl and SO2/NO from simulated incinerator and boiler flue gases. All tests were conducted in a bench-scale reactor (fixed-bed) simulating fabric filter conditions in an acid gas remova...

  15. Development of Highly Durable and Reactive Regenerable Magnesium-Based Sorbents for CO2 Separation in Coal Gasification Process

    SciTech Connect

    Javad Abbasian; Armin Hassanzadeh Khayyat; Rachid B. Slimane

    2005-06-01

    The specific objective of this project was to develop physically durable and chemically regenerable MgO-based sorbents that can remove carbon dioxide from raw coal gas at operating condition prevailing in IGCC processes. A total of sixty two (62) different sorbents were prepared in this project. The sorbents were prepared either by various sol-gel techniques (22 formulations) or modification of dolomite (40 formulations). The sorbents were prepared in the form of pellets and in granular forms. The solgel based sorbents had very high physical strength, relatively high surface area, and very low average pore diameter. The magnesium content of the sorbents was estimated to be 4-6 % w/w. To improve the reactivity of the sorbents toward CO{sub 2}, The sorbents were impregnated with potassium salts. The potassium content of the sorbents was about 5%. The dolomite-based sorbents were prepared by calcination of dolomite at various temperature and calcination environment (CO{sub 2} partial pressure and moisture). Potassium carbonate was added to the half-calcined dolomite through wet impregnation method. The estimated potassium content of the impregnated sorbents was in the range of 1-6% w/w. In general, the modified dolomite sorbents have significantly higher magnesium content, larger pore diameter and lower surface area, resulting in significantly higher reactivity compared to the sol-gel sorbents. The reactivities of a number of sorbents toward CO{sub 2} were determined in a Thermogravimetric Analyzer (TGA) unit. The results indicated that at the low CO{sub 2} partial pressures (i.e., 1 atm), the reactivities of the sorbents toward CO{sub 2} are very low. At elevated pressures (i.e., CO{sub 2} partial pressure of 10 bar) the maximum conversion of MgO obtained with the sol-gel based sorbents was about 5%, which corresponds to a maximum CO{sub 2} absorption capacity of less than 1%. The overall capacity of modified dolomite sorbents were at least one order of magnitude

  16. Development of a Rapid Cycling CO(sub 2) and H(sub 2)O Removal Sorbent

    NASA Technical Reports Server (NTRS)

    Paul, Heather; Alptekin, Goekhan; Cates, Matthew; Bernal, Casey; Dubovik, Margarita; Gershanovich, Yevgenia

    2007-01-01

    The National Aeronautics and Space Administration (NASA) planned future missions set stringent demands on the design of the Portable Life Support System (PLSS), requiring dramatic reductions in weight, decreased reliance on supplies and greater flexibility on the types of missions. Use of regenerable systems that reduce weight and volume of the Extravehicular Mobility Unit (EMU) is of critical importance to NASA, both for low orbit operations and for long duration manned missions. The carbon dioxide and humidity control unit in the existing PLSS design is relatively large, since it has to remove and store 8 hours worth of CO2. If the sorbent regeneration can be carried out during the extravehicular activity (EVA) with a relatively high regeneration frequency, the size of the sorbent canister and weight can be significantly reduced. The progress of regenerable CO2 and humidity control is leading us towards the use of a rapid cycling amine system. TDA Research, Inc. is developing compact, regenerable sorbent materials to control CO2 and humidity in the space suit ventilation loop. The sorbent can be regenerated using space vacuum during the EVA, eliminating all carbon dioxide and humidity duration-limiting elements in the life support system. The material also has applications in other areas of space exploration such as the Orion spacecraft and other longer duration exploration missions requiring regenerable technologies. This paper summarizes the results of the sorbent development, testing, and evaluation efforts to date. The results of a preliminary system analysis are also included, showing the size and volume reductions for PLSS provided by the new system.

  17. Development of regenerable copper-based sorbents for hot gas cleanup: Final technical report, September 1, 1995--August 31, 1996

    SciTech Connect

    Abbasian, J.; Slimane, R.B.; Wangerow, J.R.

    1997-05-01

    The overall objective of this study was to determine the effectiveness of the copper-chromite sorbent (developed in previous ICCI-funded projects) for longer duration application under optimum conditions in the temperature range of 550{degrees}-650{degrees}C to minimize sorbent reduction and degradation during the cyclic process. Three (3) formulations of attrition resistant granules of the copper chromite sorbent (i.e., CuCr-10, CuCr-21, and CuCr-29) as well as one (1) copper chromite sorbent in pellet form (i.e., CuCr-36) were selected for cyclic desulfurization tests. The desulfurization and regeneration capabilities of the selected formulations as well as the effects of operating parameters were determined, to identify the {open_quotes}best{close_quotes} sorbent formulation and the optimum operating conditions. The durability of the {open_quotes}best{close_quotes} sorbent formulation was determined in {open_quotes}long-term{close_quotes} multicycle tests conducted at the optimum operating conditions. The attrition resistance of the selected formulations were determined and compared with those of other sorbents, including a limestone, a dolomite, and a commercial zinc titanate sorbent. The results obtained in this study indicate that, the CuCr-29 sorbent has excellent attrition resistance and desulfurization performance, which are far superior to the commercial zinc titanate sorbents. The optimum desulfurization temperature in terms of sorbent efficiency and utilization appears to be about 600{degrees}C. Sorbent regeneration at 750{degrees}C ensured complete conversion of the copper sulfide to oxide without sulfate formation or reactivity deterioration in subsequent cycles.

  18. Development of oil-spill sorbent from straw biomass waste: Experiments and modeling studies.

    PubMed

    Tijani, Mansour M; Aqsha, Aqsha; Mahinpey, Nader

    2016-04-15

    The recovery of oil spilled on land or water has become an important issue due to environmental regulations. Canadian biomasses as fibrous materials are naturally renewable and have the potential to absorb oil-spills at different ranges. In this work, four Canadian biomasses were examined in order to evaluate their oil affinities and study parameters that could affect oil affinity when used as sorbent, such as average particle size, surface coating and reusability. Moreover, one oil sorption model was adopted and coupled with another developed model to approximate and verify the experimental findings of the oil sorbent biomasses. At an average particle size of 150-1000 μm, results showed that barley straw biomass had the highest absorbency value at 6.07 g/g, while flax straw had the lowest value at 3.69 g/g. Wheat and oat straws had oil absorbency values of 5.49 and 5.00 g/g, respectively. An average particle size of 425-600 μm indicated better absorbency values for oat and wheat straws. Furthermore, the thermal stability study revealed major weight recovery for two flame retardant coatings at hemicellulose and lignocellulose degradation temperature ranges. It was also found that oat straw biomass could be regenerated and used for many sorption/desorption cycles, as the reusability experiment showed only a 18.45% reduction in the oil absorbency value after six consecutive cycles. The developed penetration absorbency (PA) model showed oat straw adsorbed oil at the inter-particle level; and, the results of the sorption capacity model coupled with the PA model excellently predicted the oil sorption of raw and coated oat straws. PMID:26895719

  19. Development of disposal sorbents for chloride removal from high-temperature coal-derived gases

    SciTech Connect

    Krishnan, G.N.; Wood, B.J.; Canizales, A.

    1995-11-01

    The objective of this program is to develop alkali-based disposable sorbents capable of reducing HCl vapor concentrations to less than 1 ppmv in coal gas streams at temperatures in the range 400{degrees} to 750{degrees}C and pressures in the range 1 to 20 atm. The primary areas of focus of this program are investigation of different processes for fabricating the sorbents, testing their suitability for different reactor configurations, obtaining kinetic data for commercial reactor design, and updating the economics of the process.

  20. DEVELOPMENT OF DISPOSABLE SORBENTS FOR CHLORIDE REMOVAL FROM HIGH TEMPERATURE COAL-DERIVED GASES

    SciTech Connect

    Gopala Krishnan; Raghubir Gupta

    1999-09-01

    Advanced integrated-gasification combined-cycle (IGCC) and integrated-gasification fuel cell (IGFC) systems require the development of high temperature sorbents for the removal of hydrogen chloride (HCl) vapor to less than 1 parts-per-million (ppm) levels. HCl is a highly reactive, corrosive, and toxic gas which must be removed to meet environmental regulations, to protect power generation equipment, and to minimize deterioration of hot gas desulfurization sorbents. The objective of this program was to develop disposable, alkali-based sorbents capable of reducing HCl vapor levels to less than 1 ppm in the temperature range from 400 to 750 C and pressures in the range from 1 to 20 atm. The primary areas of focus of this program were to investigate different methods of sorbent fabrication, testing their suitability for different reactor configurations, obtaining reaction kinetics data, and conducting a preliminary economic feasibility assessment. This program was a joint effort between SRI International (SRI), Research Triangle Institute (RTI), and General Electric Corporate Research and Development (GE-CRD). SRI, the prime contractor and RTI, a major subcontractor, performed most of the work in this program. Thermochemical calculations indicated that sodium-based sorbents were capable of reducing HCl vapor levels to less than 1 ppm at temperatures up to 650 C, but the regeneration of spent sorbents would require complex process steps. Nahcolite (NaHCO{sub 3}), a naturally-occurring mineral, could be used as an inexpensive sorbent to remove HCl vapor in hot coal gas streams. In the current program, nahcolite powder was used to fabricate pellets suitable for fixed-bed reactors and granules suitable for fluidized-bed reactors. Pilot-scale equipment were used to prepare sorbents in large batches: pellets by disk pelletization and extrusion techniques, and granules by granulation and spray-drying techniques. Bench-scale fixed- and fluidized-bed reactors were assembled at

  1. Recovery of Rare Earths, Precious Metals and Other Critical Materials from Geothermal Waters with Advanced Sorbent Structures

    SciTech Connect

    Pamela M. Kinsey

    2015-09-30

    The work evaluates, develops and demonstrates flexible, scalable mineral extraction technology for geothermal brines based upon solid phase sorbent materials with a specific focus upon rare earth elements (REEs). The selected organic and inorganic sorbent materials demonstrated high performance for collection of trace REEs, precious and valuable metals. The nanostructured materials typically performed better than commercially available sorbents. Data contains organic and inorganic sorbent removal efficiency, Sharkey Hot Springs (Idaho) water chemsitry analysis, and rare earth removal efficiency from select sorbents.

  2. Fluidized-bed sorbents

    SciTech Connect

    Gangwal, S.K.; Gupta, R.P.

    1994-10-01

    The objectives of this project are to identify and demonstrate methods for enhancing long-term chemical reactivity and attrition resistance of zinc oxide-based mixed metal-oxide sorbents for desulfurization of hot coal-derived gases in a high-temperature, high-pressure (HTHP) fluidized-bed reactor. In this program, regenerable ZnO-based mixed metal-oxide sorbents are being developed and tested. These include zinc ferrite, zinc titanate, and Z-SORB sorbents. The Z-SORB sorbent is a proprietary sorbent developed by Phillips Petroleum Company (PPCo).

  3. Development of new multifunctional terpolymer sorbent for proteomics applications.

    PubMed

    Najam-ul-Haq, Muhammad; Saeed, Adeela; Jabeen, Fahmida; Hussain, Dilshad; Khan, Naseem; Shabir, Maryam; Raza, Nadeem; Ashiq, Muhammad Naeem; Malana, Muhammad Aslam; Zafar, Zafar Iqbal

    2015-07-01

    Determination of the availability of phases for specific separations is an important task achieved by a separation chemist. This becomes vital when the complex samples like biofluids are dealt with in proteome science. The work presented here involves the synthesis and application of terpolymeric sorbent with different functionalizations adopted for the selective enrichment of biomolecules of interest from biological fluids. Synthesis of terpolymer was carried out by the radical polymerization of monomers: methyl acrylate, acrylic acid and vinyl acetate with diethylene glycol dimethacrylate as cross-linking agent, benzoyl peroxide as initiator and chloroform as a porogenic solvent. Characterization was done through Fourier transform infrared spectroscopy, scanning electron microscopy and nitrogen adsorption porosimetry. The polymer was further modified to immobilized metal ion affinity chromatographic material, with immobilized Fe(3+)/La(3+) ions that allowed phosphopeptide enrichment from tryptic digests of standard proteins as well as milk, egg yolk and human serum. Sensitivity of enrichment down to 50 fmol was achieved in the presence of complex protein background as bovine serum albumin. Hydrophobicity was introduced through octadecyl amine, which provides comparable results to ZipTip C18/C4 for desalting of complex mixtures of all caseins. Analysis of the enriched content was performed by Matrix Assisted Laser Desorption Ionization Mass Spectrometry (MALDI-MS). PMID:25402016

  4. Field evaluation of natural gas and dry sorbent injection for MWC emissions control

    SciTech Connect

    Wohadlo, S; Abbasi, H; Cygan, D

    1993-10-01

    The Institute of Gas Technology (IGT), in cooperation with the Olmsted Waste-to-Energy Facility (OWEF) and with subcontracted engineering services from the Energy and Environmental Research Corporation (EER), has completed the detailed engineering and preparation of construction specifications for an Emissions Reduction Testing System (ERTS). The ERTS has been designed for retrofit to one of two 100-ton/day municipal waste combustors at the OWEF, located in Rochester, Minnesota. The purpose of the retrofit is to conduct a field evaluation of a combined natural gas and sorbent injection process (IGT`s METHANE de-TOX{sup SM}, IGT Patent No. 5,105,747) for reducing the emissions of oxides of nitrogen (NO{sub x}), hydrochloric acid (HCI), oxides of sulfur (SO{sub x}), carbon monoxide (CO), total hydrocarbons (THC), and chlorinated hydrocarbons (dioxin/furans). In addition, the design includes modifications for the control of heavy metals (HM). Development of the process should allow the waste-to-energy industry to meet the Federal New Source Performance Standards for these pollutants at significantly lower costs when compared to existing technology of Thermal deNO{sub x} combined with spray dryer scrubber/fabric filters. Additionally, the process should reduce boiler corrosion and increase both the thermal and power production efficiency of the facility.

  5. Evaluation of Sorbents for Acetylene Separation in Atmosphere Revitalization Loop Closure

    NASA Technical Reports Server (NTRS)

    Abney, Morgan B.; Miller, Lee A.; Barton, Katherine

    2012-01-01

    State-of-the-art carbon dioxide reduction technology uses a Sabatier reactor to recover water from metabolic carbon dioxide. In order to maximize oxygen loop closure, a byproduct of the system, methane, must be reduced to recover hydrogen. NASA is currently exploring a microwave plasma methane pyrolysis system for this purpose. The resulting product stream of this technology includes unreacted methane, product hydrogen, and acetylene. The hydrogen and the small amount of unreacted methane resulting from the pyrolysis process can be returned to the Sabatier reactor thereby substantially improving the overall efficiency of the system. However, the acetylene is a waste product that must be removed from the pyrolysis product. Two materials have been identified as potential sorbents for acetylene removal: zeolite 4A, a commonly available commercial sorbent, and HKUST-1, a newly developed microporous metal. This paper provides an explanation of the rationale behind acetylene removal and the results of separation testing with both materials

  6. Evaluation of Sorbents for Acetylene Separation in Atmosphere Revitalization Loop Closure

    NASA Technical Reports Server (NTRS)

    Abney, Morgan B.; Miller, Lee A.; Barton, Katherine

    2011-01-01

    State-of-the-art carbon dioxide reduction technology uses a Sabatier reactor to recover water from metabolic carbon dioxide. In order to maximize oxygen loop closure, a byproduct of the system, methane, must be reduced to recover hydrogen. NASA is currently exploring a microwave plasma methane pyrolysis system for this purpose. The resulting product stream of this technology includes unreacted methane, product hydrogen, and acetylene. The hydrogen and the small amount of unreacted methane resulting from the pyrolysis process can be returned to the Sabatier reactor thereby substantially improving the overall efficiency of the system. However, the acetylene is a waste product that must be removed from the pyrolysis product. Two materials have been identified as potential sorbents for acetylene removal: zeolite 4A, a commonly available commercial sorbent, and HKUST-1, a newly developed microporous metal. This paper provides an explanation of the rationale behind acetylene removal and the results of separation testing with both materials.

  7. Development of Superior Sorbents for Separation of CO2 from Flue Gas at a Wide Temperature Range During Coal Combustion

    SciTech Connect

    Panagiotis G. Smirniotis

    2007-06-30

    In chapter 1, the studies focused on the development of novel sorbents for reducing the carbon dioxide emissions at high temperatures. Our studies focused on cesium doped CaO sorbents with respect to other major flue gas compounds in a wide temperature range. The thermo-gravimetric analysis of sorbents with loadings of CaO doped on 20 wt% cesium demonstrated high CO{sub 2} sorption uptakes (up to 66 wt% CO{sub 2}/sorbent). It is remarkable to note that zero adsorption affinity for N{sub 2}, O{sub 2}, H{sub 2}O and NO at temperatures as high as 600 C was observed. For water vapor and nitrogen oxide we observed a positive effect for CO{sub 2} adsorption. In the presence of steam, the CO{sub 2} adsorption increased to the highest adsorption capacity of 77 wt% CO{sub 2}/sorbent. In the presence of nitrogen oxide, the final CO{sub 2} uptake remained same, but the rate of adsorption was higher at the initial stages (10%) than the case where no nitrogen oxide was fed. In chapter 2, Ca(NO{sub 3}){sub 2} {center_dot} 4H{sub 2}O, CaO, Ca(OH){sub 2}, CaCO{sub 3}, and Ca(CH{sub 3}COO){sub 2} {center_dot} H{sub 2}O were used as precursors for synthesis of CaO sorbents on this work. The sorbents prepared from calcium acetate (CaAc{sub 2}-CaO) resulted in the best uptake characteristics for CO{sub 2}. It possessed higher BET surface area and higher pore volume than the other sorbents. According to SEM images, this sorbent shows 'fluffy' structure, which probably contributes to its high surface area and pore volume. When temperatures were between 550 and 800 C, this sorbent could be carbonated almost completely. Moreover, the carbonation progressed dominantly at the initial short period. Under numerous adsorption-desorption cycles, the CaAc{sub 2}-CaO demonstrated the best reversibility, even under the existence of 10 vol % water vapor. In a 27 cyclic running, the sorbent sustained fairly high carbonation conversion of 62%. Pore size distributions indicate that their pore volume

  8. Enhanced durability of high-temperature desulfurization sorbents for moving-bed applications. Option 2 Program: Development and testing of zinc titanate sorbents

    SciTech Connect

    Ayala, R.E.

    1993-04-01

    One of the most advantageous configurations of the integrated gasification combined cycle (IGCC) power system is coupling it with a hot gas cleanup for the more efficient production of electric power in an environmentally acceptable manner. In conventional gasification cleanup systems, closely heat exchangers are necessary to cool down the fuel gases for cleaning, sometimes as low as 200--300{degree}F, and to reheat the gases prior to injection into the turbine. The result is significant losses in efficiency for the overall power cycle. High-temperature coal gas cleanup in the IGCC system can be operated near 1000{degree}F or higher, i.e., at conditions compatible with the gasifier and turbine components, resulting is a more efficient overall system. GE is developing a moving-bed, high-temperature desulfurization system for IGCC power systems in which mixed-metal oxides are currently being used as desulfurization sorbents. The objective of this contract is to identify and test fabrication methods and sorbent chemical compositions that enhance the long-term chemical reactivity and mechanical durability of zinc ferrite and other novel sorbents for moving-bed, high-temperature desulfurization of coal-derived gases. Zinc ferrite was studied under the base program of this contract. In the next phase of this program novel sorbents, particularly zinc titanate-based sorbents, are being studied under the remaining optional programs. This topical report summarizes only the work performed under the Option 2 program. In the course of carrying out the program, more than 25 zinc titanate formulations have been prepared and characterized to identify formulations exhibiting enhanced properties over the baseline zinc titanate formulation selected by the US Department of Energy.

  9. Utility flue gas mercury control via sorbent injection

    SciTech Connect

    Chang, R.; Carey, T.; Hargrove, B.

    1996-12-31

    The potential for power plant mercury control under Title III of the 1990 Clean Air Act Amendments generated significant interest in assessing whether cost effective technologies are available for removing the mercury present in fossil-fired power plant flue gas. One promising approach is the direct injection of mercury sorbents such as activated carbon into flue gas. This approach has been shown to be effective for mercury control from municipal waste incinerators. However, tests conducted to date on utility fossil-fired boilers show that it is much more difficult to remove the trace species of mercury present in flue gas. EPRI is conducting research in sorbent mercury control including bench-scale evaluation of mercury sorbent activity and capacity with simulated flue gas, pilot testing under actual flue gas conditions, evaluation of sorbent regeneration and recycle options, and the development of novel sorbents. A theoretical model that predicts maximum mercury removals achievable with sorbent injection under different operating conditions is also being developed. This paper presents initial bench-scale and model results. The results to date show that very fine and large amounts of sorbents are needed for mercury control unless long residence times are available for sorbent-mercury contact. Also, sorbent activity and capacity are highly dependent on flue gas composition, temperature, mercury species, and sorbent properties. 10 refs., 4 figs., 2 tabs.

  10. Novel sorbents for environmental remediation

    NASA Astrophysics Data System (ADS)

    Manariotis, Ioannis D.; Karapanagioti, Hrissi K.; Werner, David

    2014-05-01

    Nowadays, one of the major environmental problems is the pollution of aquatic systems and soil by persistent pollutants. Persistent pollutants have been found widespread in sediments, surface waters, and drinking water supplies. The removal of pollutants can be accomplished prior to their discharge to receiving bodies or by immobilizing them onto soil. Sorption is the most commonly applied process, and activated carbons have been widely used. Rapid progress in nanotechnology and a new focus on biomass-based instead of non-renewable starting materials have produced a wide range of novel engineered sorbents including biosorbents, biochars, carbon-based nanoparticles, bio-nano hybrid materials, and iron-impregnated activated carbons. Sorbent materials have been used in environmental remediation processes and especially in agricultural soil, sediments and contaminated soil, water treatment, and industrial wastewater treatment. Furthermore, sorbents may enhance the synergistic action of other processes, such as volatilization and biodegradation. Novel sorbents have been employed for the removal or immobilization of persistent pollutants such as and include heavy metals (As, Cr, Cu, Pb, Cd, and Hg), halogenated organic compounds, endocrine disrupting chemicals, metalloids and non-metallic elements, and other organic pollutants. The development and evaluation of novel sorbents requires a multidisciplinary approach encompassing environmental, nanotechnology, physical, analytical, and surface chemistry. The necessary evaluations encompass not only the efficiency of these materials to remove pollutants from surface waters and groundwater, industrial wastewater, polluted soils and sediments, etc., but also the potential side-effects of their environmental applications. The aim of this work is to present the results of the use of biochar and impregnated carbon sorbents for the removal of organic pollutants and metals. Furthermore, the new findings from the forthcoming session

  11. Development of novel copper-based sorbents for hot-gas cleanup. Technical report, March 1, 1992--May 31, 1992

    SciTech Connect

    Abbasian, J.; Hill, A.H.; Wangerow, J.R.; Flytzani-Stephanopoulos, M.; Bo, L.; Patel, C.

    1992-10-01

    The objective of this investigation is to evaluate several novel copper-based binary oxides for their suitability as regenerable sorbents for hot gas cleanup application in the temperature range of 650{degrees} to 850{degrees}C. During this quarter cyclic sulfidation/regeneration tests of the sorbents Cu{sub 2}Cr-O and Cu-Ce-0 were conducted using different compositions of the feed gases to investigate the effects of H{sub 2}0, H{sub 2} and CO. These tests were conducted in a packed-bed microreactor at 850{degrees}C. The results of these tests showed that H{sub 2} and CO (along with C02) had a significant effect on the H{sub 2}S pre-breakthrough levels, whereas H{sub 2}0 did not have an effect. The physical properties of the fresh and reacted samples of the Cu-2Cr-O and Cu-Ce-0 sorbents prepared in this program and used in the cyclic sulfidation/regeneration tests were also measured. In addition, sulfidation/regeneration tests were conducted using two commercial copper chromite sorbents (G-13 and G-89, United Catalyst, Inc.) and a zinc titanate sorbent (L-3014) in a one-inch fluidized-bed reactor at 650{degrees}C. The G-13 sorbent appears to have a much higher sulfur capacity than the G-89 sorbent.

  12. Development of Spheroidal Inorganic Sorbents for Treatment of Acidic Salt-Bearing Liquid Waste

    SciTech Connect

    Collins, J.L.

    2001-09-07

    A spheroidal composite inorganic sorbent was developed for U.S. Department of Energy-Efficient Separations and Processing Crosscutting Program (USDOE-ESP) for potential use in removing radioactive cesium isotopes from acidic high-salt waste streams such as those at Idaho National Engineering and Environmental Laboratory (INEEL). The sorbent, zirconium monohydrogen phosphate (ZrHP) embedded with fine powder of ammonium molybdophosphate (AMP), was prepared using a unique internal gelation process which can be used to make porous reproducible microspheres that are structurally strong, have a low tendency for surface erosion, and improve the flow dynamics for column operations. Both ZrHP and AMP are excellent sorbent materials and, being inorganic, are stable in high radiation fields. AMP is a very effective sorbent for removing cesium from salt-bearing waste streams for a wide range of acidity. In the pH range of 2 to 10, ZrHP is also a very effective sorbent for removing Cs, Sr, Th, U(VI), Pu(IV), Am(III), Hg, and Pb from streams of lower ionic concentrations. Crucial to developing the spheroidal AMP-ZrHP sorbent was to determine the ideal weight percentage of AMP that could be embedded in the ZrHP microspheres in order to maintain the structural integrity of the microspheres and also achieve a good cesium separation. A total of 12 preparations were made. The dry weight percentage of AMP ranged from 30 to 60. Overall, the best composite microspheres prepared contained 50% AMP (by dry weight measurement). Another composite microsphere, which was composed of titanium monohydrogen phosphate (TiHP) embedded with 18 wt % (air-dried weight) potassium cobalt hexacyanoferrate (KCoCF) and developed for a different separations application, was also batch tested for comparison. It proved to be as effective in removing,the cesium as the air-dried AMP (50 wt %)-ZrHP. Granular KCoCF was also prepared and was very effective. Large samples of each of these materials were sent to

  13. Development of novel copper-based sorbents for hot-gas cleanup. Technical report, 1 March--31 May 1994

    SciTech Connect

    Abbasian, J.; Hill, A.H.; Flytzani-Stephanopoulos, M.; Li, Z.

    1994-09-01

    The objective of this investigation is to evaluate two novel copper-based sorbents, namely copper-chromium and copper-cerium, for their effectiveness in removing hydrogen sulfide from fuel gas in the temperature range of 650 to 850 C. Such high temperatures will be required for the new generation of gas turbines (inlet > 750 C) in Integrated Gasification Combined Cycle (IGCC) systems. Results of fixed-bed reactor tests conducted in this quarter, indicate that, at 750 C, pre-reduction with H{sub 2} in the presence of H{sub 2}O does not effect the performance of either sorbent for H{sub 2}S removal. For the pre-reduced CuCr{sub 2}O{sub 4} sorbent, copper utilization before the first H{sub 2}S breakthrough is substantially higher in synthesis feed gas mixture than in feed gas containing 30 Vol% H{sub 2}, and slightly lower than in 10 vol% H{sub 2}. In sulfidation-regeneration testing of copper- and additive-rich sorbents, chromium-rich CuO-3Cr{sub 2}O{sub 4} sorbent demonstrated very high H{sub 2}S removal efficiency and high copper conversion levels (comparable to that of the 1:1 molar composition sorbent). Similar results were obtained with the cerium-rich CuO-3CeO{sub 2} sorbent, but only for the first cycle. The H{sub 2}S removal performance of both copper-rich sorbents was inferior to that of the respective 1:1 molar compositions. CuO-CeO{sub 2} sorbent testing in a TGA indicates no appreciable decrease in the sulfidation rate over 5 1/2 cycles. However, weight changes during regeneration of the CuO-CeO{sub 2} suggest that some copper or cerium sulfates formed.

  14. Bench-scale Development of an Advanced Solid Sorbent-based CO2 Capture Process for Coal-fired Power Plants

    SciTech Connect

    Nelson, Thomas; Kataria, Atish; Soukri, Mustapha; Farmer, Justin; Mobley, Paul; Tanthana, Jak; Wang, Dongxiang; Wang, Xiaoxing; Song, Chunshan

    2015-12-31

    of this project was to mitigate the technical and economic risks associated with the scale-up of solid sorbent-based CO2 capture processes, enabling subsequent larger pilot demonstrations and ultimately commercial deployment. An integrated development approach has been a key focus of this project in which process development, sorbent development, and economic analyses have informed each of the other development processes. Development efforts have focused on improving the performance stability of sorbent candidates, refining process engineering and design, and evaluating the viability of the technology through detailed economic analyses. Sorbent advancements have led to a next generation, commercially-viable CO2 capture sorbent exhibiting performance stability in various gas environments and a physically strong fluidizable form. The team has reduced sorbent production costs and optimized the production process and scale-up of PEI-impregnated, fluidizable sorbents. Refinement of the process engineering and design, as well as the construction and operation of a bench-scale research unit has demonstrated promising CO2 capture performance under simulated coal-fired flue gas conditions. Parametric testing has shown how CO2 capture performance is impacted by changing process variables, such as Adsorber temperature, Regenerator temperature, superficial flue gas velocity, solids circulation rate, CO2 partial pressure in the Regenerator, and many others. Long-term testing has generated data for the project team to set the process conditions needed to operate a solids-based system for optimal performance, with continuous 90% CO2 capture, and no operational interruptions. Data collected from all phases of testing has been used to develop a detailed techno-economic assessment of RTI’s technology. These detailed analyses show that RTI’s technology has significant economic advantages over current amine scrubbing

  15. Evaluation of electrospun polyvinyl chloride/polystyrene fibers as sorbent materials for oil spill cleanup.

    PubMed

    Zhu, Haitao; Qiu, Shanshan; Jiang, Wei; Wu, Daxiong; Zhang, Canying

    2011-05-15

    A novel, high-capacity oil sorbent consisting of polyvinyl chloride (PVC)/polystyrene (PS) fiber was prepared by an electrospinning process. The sorption capacity, oil/water selectivity, and sorption mechanism of the PVC/PS sorbent were studied. The results showed that the sorption capacities of the PVC/PS sorbent for motor oil, peanut oil, diesel, and ethylene glycol were 146, 119, 38, and 81 g/g, respectively. It was about 5-9 times that of a commercial polypropylene (PP) sorbent. The PVC/PS sorbent also had excellent oil/water selectivity (about 1000 times) and high buoyancy in the cleanup of oil over water. The SEM analysis indicated that voids among fibers were the key for the high capacity. The electrospun PVC/PS sorbent is a better alternative to the widely used PP sorbent for oil spill cleanup.

  16. EVALUATION OF CARBON DIOXIDE CAPTURE FROM EXISTING COAL FIRED PLANTS BY HYBRID SORPTION USING SOLID SORBENTS

    SciTech Connect

    Benson, Steven; Palo, Daniel; Srinivasachar, Srivats; Laudal, Daniel

    2014-12-01

    Under contract DE-FE0007603, the University of North Dakota conducted the project Evaluation of Carbon Dioxide Capture from Existing Coal Fired Plants by Hybrid Sorption Using Solid Sorbents. As an important element of this effort, an Environmental Health and Safety (EH&S) Assessment was conducted by Barr Engineering Co. (Barr) in association with the University of North Dakota. The assessment addressed air and particulate emissions as well as solid and liquid waste streams. The magnitude of the emissions and waste streams was estimated for evaluation purposes. EH&S characteristics of materials used in the system are also described. This document contains data based on the mass balances from both the 40 kJ/mol CO2 and 80 kJ/mol CO2 desorption energy cases evaluated in the Final Technical and Economic Feasibility study also conducted by Barr Engineering.

  17. Development and Testing of a Sorbent-Based Atmosphere Revitalization System 2010/2011

    NASA Technical Reports Server (NTRS)

    Miller, Lee A.; Knox, James C.

    2012-01-01

    Spacecraft being developed for future exploration missions incorporate Environmental Control and Life Support Systems (ECLSS) that limit weight, power, and volume thus requiring systems with higher levels of efficiency while maintaining high dependability and robustness. For air revitalization, an approach that meets those goals utilizes a regenerative Vacuum-Swing Adsorption (VSA) system that removes 100% of the CO2 from the cabin atmosphere as well as 100% of the water. A Sorbent Based Atmosphere Revitalization (SBAR) system is a VSA system that utilizes standard commercial adsorbents that have been proven effective and safe in spacecraft including Skylab and the International Space Station. The SBAR system is the subject of a development, test, and evaluation program that is being conducted at NASA s Marshall Space Flight Center. While previous testing had validated that the technology is a viable option, potential improvements to system design and operation were identified. Modifications of the full-scale SBAR test articles and adsorption cycles have been implemented and have shown significant performance gains resulting in a decrease in the consumables required for a mission as well as improved mission safety. Previous testing had utilized single bed test articles, during this period the test facility was enhanced to allow testing on the full 2-bed SBAR system. The test facility simulates a spacecraft ECLSS and allows testing of the SBAR system over the full range of operational conditions using mission simulations that assess the real-time performance of the SBAR system during scenarios that include the metabolic transients associated with extravehicular activity. Although future manned missions are currently being redefined, the atmosphere revitalization requirements for the spacecraft are expected to be quite similar to the Orion and the Altair vehicles and the SBAR test program addressed validation to the defined mission requirements as well as operation

  18. A novel sorbent for transport reactors and fluidized bed reactors

    SciTech Connect

    Copeland, R.; Cesario, M.; Gershanovich, Y.; Sibold, J.; Windecker, B.

    1998-12-31

    Coal Fired Gasifier Combined Cycles (GCC) have both high efficiency and very low emissions. GCCs critically need a method of removing the H{sub 2}S produced from the sulfur in the coal from the hot gases. There has been extensive research on hot gas cleanup systems, focused on the use of a zinc oxide based sorbent (e.g., zinc titanate). TDA Research, Inc. (TDA) is developing a novel sorbent with improved attrition resistance for transport reactors and fluidized bed reactors. The authors are testing sorbents at conditions simulating the operating conditions of the Pinon Pine clean coal technology plant. TDA sulfided several different formulations at 538 C and found several that have high sulfur capacity when tested in a fluidized bed reactor. TDA initiated sorbent regeneration at 538 C. The sorbents retained chemical activity with multiple cycles. Additional tests will be conducted to evaluate the best sorbent formulation.

  19. CHARACTERIZATION OF ADVANCED SORBENTS FOR DRY SO2 CONTROL

    EPA Science Inventory

    The paper discusses the development of new flyash/lime sorbents for removing SO2 from coal-fired flue gas. Flyash/lime weight ratios of 1:1 to 10:1 and several additives to these sorbents for promoting their reactivity were evaluated in a bench-scale reactor simulating conditions...

  20. FIELD TEST PROGRAM FOR EVALUATION OF SORBENT INJECTION FOR MERCURY CONTROL

    SciTech Connect

    Sharon Sjostrom

    2004-02-12

    The power industry in the U.S. is faced with meeting new regulations to reduce the emissions of mercury compounds from coal-fired plants. These regulations are directed at the existing fleet of nearly 1,100 boilers. These plants are relatively old with an average age of over 40 years. Although most of these units are capable of operating for many additional years, there is a desire to minimize large capital expenditures because of the reduced (and unknown) remaining life of the plant to amortize the project. Injecting a sorbent such as powdered activated carbon into the flue gas represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. The overall objective of this test program described in this quarterly report is to evaluate the capabilities of activated carbon injection at four plants with configurations that together represent 78% of the existing coal-fired generation plants. This technology was successfully evaluated in NETL's Phase I tests at scales up to 150 MW, on plants burning subbituminous and bituminous coals and with ESPs and fabric filters. The tests also identified issues that still need to be addressed, such as evaluating performance on other configurations, optimizing sorbent usage (costs), and gathering longer term operating data to address concerns about the impact of activated carbon on plant equipment and operations. The four sites identified for testing are Sunflower Electric's Holcomb Station, AmerenUE's Meramec Station, AEP's Conesville Station, and Ontario Power Generation's Nanticoke Station. This is the first quarterly report for this project. This report includes an overview of the plans for the project. Field testing is scheduled to begin next quarter. In general, quarterly reports will be used to provide project overviews, project status, and technology transfer information. Topical reports will be prepared to present detailed technical information.

  1. Sorbents for mercury removal from flue gas

    SciTech Connect

    Granite, Evan J.; Hargis, Richard A.; Pennline, Henry W.

    1998-01-01

    A review of the various promoters and sorbents examined for the removal of mercury from flue gas is presented. Commercial sorbent processes are described along with the chemistry of the various sorbent-mercury interactions. Novel sorbents for removing mercury from flue gas are suggested. Since activated carbons are expensive, alternate sorbents and/or improved activated carbons are needed. Because of their lower cost, sorbent development work can focus on base metal oxides and halides. Additionally, the long-term sequestration of the mercury on the sorbent needs to be addressed. Contacting methods between the flue gas and the sorbent also merit investigation.

  2. Aerogel sorbents

    DOEpatents

    Begag, Redouane; Rhine, Wendell E; Dong, Wenting

    2016-04-05

    The current invention describes methods and compositions of various sorbents based on aerogels of various silanes and their use as sorbent for carbon dioxide. Methods further provide for optimizing the compositions to increase the stability of the sorbents for prolonged use as carbon dioxide capture matrices.

  3. Laboratory evaluation of high-temperature sulfur removal sorbents for direct coal-fired turbines: Final report

    SciTech Connect

    Newby, R.A.; DeZubay, E.A.; Chamberlin, R.M.

    1987-06-01

    Direct coal-fired turbine concepts currently being developed require substantial levels of sulfur removal from high-temperature gas streams. Calcium-based sorbents, limestones, dolomites, limes and lime hydrates, are capable of sulfur removal in direct coal-fired turbine combustor environments at temperature up to 1200/degree/C. Two types of desulfurizer processes are considered in this report using calcium- based sorbents: fluidized bed desulfurizer using coarse sorbent particles (300-1000 ..mu..m), and entrained desulfurizer using fine sorbent particles (1-40 ..mu..m). Small-scale laboratory tests were performed on a variety of calcium-based sorbents to determine the kinetics of sulfation and sulfidation over ranges of conditions applicable to both types of desulfurizer processes. Correlations are developed in the report for the effect of pressure; temperature, and particle size. Engineering models are also developed for both desulfurizer types that incorporate the laboratory reaction kinetics and predict potential commercial performance and performance trends. It is concluded that both desulfurizer concepts can be effective in direct coal-fired turbines, with calcium-to-sulfur molar feed ratios ranging from 1.5 to 3.0, if the correct calcium-based sorbent is selected, and if applicable design and operating conditions are identified. Both desulfurizer concepts have limitations and key development requirements, and site and fuel specific engineering assessment is required to select the best concept for a given combustor system. The influence of the desulfurizer concepts on turbine protection, through their influence on particle loading and alkali release must also be assessed. 51 refs., 73 figs., 9 tabs.

  4. Advanced in-duct sorbent injection for SO{sub 2} control. Topical report No. 6, Task 5: Conceptual commercial process design and economic evaluation

    SciTech Connect

    Deluliis, N.J.; Maskew, J.T.

    1994-12-01

    The objective of this research project is the development of a second generation in-duct sorbent injection technology as a cost-effective compliance option for the 1990 Clean Air Act Amendments. Research focused on the Advanced Coolside Process, which has shown the potential of exceeding the performance targets of 90% SO{sub 2} removal and 60% sorbent utilization. In Task 5, Conceptual Process Design and Economic Evaluation, the economics of the CONSOL Advanced Coolside Process as a Clean Air Act compliance option were evaluated. A conceptual process design for full-scale, coal-fired applications is described. Advanced Coolside is compared to conventional Limestone Forced Oxidation (LSFO) wet FGD technology. The process economics for coal sulfur levels ranging from 1.0% to 3.5% (as-received) and plant sizes ranging from 160 to 512 gross MW were investigated, In addition, the economics of on-site versus off-site lime hydration and the cost sensitivity to delivered pebble lime and hydrate prices are investigated, Advanced in-duct sorbent injection enjoys a capital and levelized cost advantage relative to LSFO in all cases examined in this study. As a result of this study and others made during this contract, the following conclusions can be made: (1) The capital cost of Advanced Coolside is 55% to 60% less than that of LSFO and varies slightly depending on coal sulfur content and plant size. (2) The total levelized SO{sub 2} control cost advantage relative to LSFO varies from 15% to 35% over the range of coal sulfur contents and plant sizes evaluated. This cost advantage is sensitive to sorbent transportation charges. As a result, the economics are site-specific. (3) The experimental optimizations based on interim economic analyses were the key to capital and levelized cost reductions.

  5. Evaluation of different cleanup sorbents for multiresidue pesticide analysis in fatty vegetable matrices by liquid chromatography tandem mass spectrometry.

    PubMed

    López-Blanco, Rafael; Nortes-Méndez, Rocío; Robles-Molina, José; Moreno-González, David; Gilbert-López, Bienvenida; García-Reyes, Juan F; Molina-Díaz, Antonio

    2016-07-22

    In this article we have evaluated the performance of different sorbents for the cleanup step in multiresidue pesticide analysis in fatty vegetable matrices using QuEChERS methodology. The three different matrices tested (olive oil, olives and avocado) were partitioned using acetonitrile prior to cleanup step. Afterwards, the supernatant was purified using different sorbents: C18+PSA (primary secondary amine), Z-Sep(+) (zirconium oxide and C18 dual bonded to silica), Z-Sep (zirconium oxide bonded to silica) and a novel sorbent Enhanced Matrix Removal-Lipid (EMR) whose composition has not been disclosed. The different cleanup strategies were compared for a group of 67 representative pesticides in terms of recovery rates, matrix effects, extract cleanliness and precision using ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). The best extraction efficiencies in olive oil matrix were obtained using EMR, while the results for olives and avocado were pretty similar amongst the different sorbents with an overall lower performance in terms of matrix effects and recovery rates compared to olive oil data, particularly in olives due to the higher complexity and concentration of coextracted species. On the other hand, the average reproducibility was clearly better when EMR sorbent was employed in all selected matrices for most pesticides (RSD<10% for 45, 52, and 56 pesticides in avocado, olives and olive oil respectively). The best results in terms of matrix effects were also obtained with EMR; with signal suppression lower than 20% for 79%, 16% and 51% of pesticides tested in olive oil, olives and avocado respectively. Using EMR as cleanup sorbent, limits of quantitation using UHPLC-MS/MS, ranged from 0.10 to 90μgkg(-1), allowing their determination at the low concentration levels demanded by current olive oil regulations in most cases. PMID:27328883

  6. Evaluation of different cleanup sorbents for multiresidue pesticide analysis in fatty vegetable matrices by liquid chromatography tandem mass spectrometry.

    PubMed

    López-Blanco, Rafael; Nortes-Méndez, Rocío; Robles-Molina, José; Moreno-González, David; Gilbert-López, Bienvenida; García-Reyes, Juan F; Molina-Díaz, Antonio

    2016-07-22

    In this article we have evaluated the performance of different sorbents for the cleanup step in multiresidue pesticide analysis in fatty vegetable matrices using QuEChERS methodology. The three different matrices tested (olive oil, olives and avocado) were partitioned using acetonitrile prior to cleanup step. Afterwards, the supernatant was purified using different sorbents: C18+PSA (primary secondary amine), Z-Sep(+) (zirconium oxide and C18 dual bonded to silica), Z-Sep (zirconium oxide bonded to silica) and a novel sorbent Enhanced Matrix Removal-Lipid (EMR) whose composition has not been disclosed. The different cleanup strategies were compared for a group of 67 representative pesticides in terms of recovery rates, matrix effects, extract cleanliness and precision using ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). The best extraction efficiencies in olive oil matrix were obtained using EMR, while the results for olives and avocado were pretty similar amongst the different sorbents with an overall lower performance in terms of matrix effects and recovery rates compared to olive oil data, particularly in olives due to the higher complexity and concentration of coextracted species. On the other hand, the average reproducibility was clearly better when EMR sorbent was employed in all selected matrices for most pesticides (RSD<10% for 45, 52, and 56 pesticides in avocado, olives and olive oil respectively). The best results in terms of matrix effects were also obtained with EMR; with signal suppression lower than 20% for 79%, 16% and 51% of pesticides tested in olive oil, olives and avocado respectively. Using EMR as cleanup sorbent, limits of quantitation using UHPLC-MS/MS, ranged from 0.10 to 90μgkg(-1), allowing their determination at the low concentration levels demanded by current olive oil regulations in most cases.

  7. PREPARATION AND EVALUATION OF MODIFIED LIME AND SILICA-LIME SORBENTS FOR MERCURY VAPOR EMISSIONS CONTROL

    EPA Science Inventory

    The paper discusses current efforts to improve the uptake of mercury species by increasing active sites and adding oxidative species to the sorbent. (NOTE: Previous work showed that mercury chloride vapor is readily absorbed by calcium-based sorbents as an acid gas in environmen...

  8. Sorbent suppliers

    SciTech Connect

    Vedder, M.

    1994-03-01

    Sorbents are used to absorb or contain spilled and leaking chemicals, oils, lubricants and other process fluids. They are commonly used around the base of machinery in industrial applications, and in remediating oil spills on land and water. Sorbents are made from biodegradable, inorganic or synthetic materials. Organic materials include corn cobs, wood pulp, paper fiber and cotton. Inorganic materials include clay, perlite, expanded silicates and expanded mica. Synthetic sorbents are made from petroleum- or plastic-based materials such as polyurethane, polyethylene or polypropylene. Sorbents are available in a variety of forms, including pads, rolls, booms, pillows and loose particulate.

  9. Development of novel copper-based sorbents for hot-gas cleanup. Final technical report, September 1, 1991--August 31, 1992

    SciTech Connect

    Abbasian, J.; Hill, A.H.; Wangerow, J.R.; Flytzani-Stephanopoulos, M.; Bo, Luhong; Patel, C.; Chang, D.

    1992-12-31

    The objective of this investigation was to evaluate several novel copper-based binary oxides for their suitability as regenerable sorbents for hot gas cleanup application in the temperature range of 650{degree} to 850{degree}C. To achieve this objective, several novel binary oxides of copper were systematically evaluated and ranked in terms of their high-temperature stability against reduction to metal, sulfidation reactivity, and regenerability. The sorbents studied included oxides of chromium, cerium, aluminum, magnesium, manganese, titanium, iron, and silicon. The results of initial testing indicated that mixed binary oxides of copper with chromium (CuCr{sub 2}O{sub 4}) and cerium (CuO{circle_dot}CeO{sub 2}) were the most promising sorbents for such high temperature gas cleanup applications. These two sorbents were further evaluated in cyclic sulfidation/regeneration tests in 10--15 cycles to determine the effect of operating conditions on their performance. The results of this investigation indicate that the two selected sorbents, copper-chromium and copper-cerium, are capable of removing H{sub 2}S from the hot fuel gas to very low levels (<10 ppmv) at temperatures as high as 850{degree}C with good sorbent regenerability in cyclic process. These sorbents should be further studied to achieve optimum sorbent composition for hot gas cleanup application.

  10. Long-term evaluation of 'BARC 68Ge/68Ga generator' based on the nanoceria-polyacrylonitrile composite sorbent.

    PubMed

    Chakravarty, Rubel; Chakraborty, Sudipta; Ram, Ramu; Dash, Ashutosh; Pillai, M R A

    2013-10-01

    This article describes the long-term evaluation of a nanoceria-polyacrylonitrile (CeO2-PAN) composite sorbent-based (68)Ge/(68)Ga generator reported. This generator used the new CeO2-PAN composite sorbent for preparation of the (68)Ge/(68)Ga generator. Since this sorbent has not been previously evaluated, a thorough long-term evaluation of the performance of the generator is necessary to ensure its applicability for clinical practice. The performance of the generator was evaluated in terms of (68)Ga yield, (68)Ge breakthrough, radioactive concentration of the (68)Ga solution, and suitability of the (68)Ga for the preparation of (68)Ga-labeled tracers. The (68)Ge/(68)Ga generator was able to provide a (68)Ga activity with consistent yields (>70%) and having acceptable radionuclidic (<10(-4)% of (68)Ge breakthrough), radiochemical, and chemical purities for an extended period of time. The eluted (68)GaCl3 is useful for the majority of the (68)Ga complexation chemistry. PMID:23745686

  11. Long-term evaluation of 'BARC 68Ge/68Ga generator' based on the nanoceria-polyacrylonitrile composite sorbent.

    PubMed

    Chakravarty, Rubel; Chakraborty, Sudipta; Ram, Ramu; Dash, Ashutosh; Pillai, M R A

    2013-10-01

    This article describes the long-term evaluation of a nanoceria-polyacrylonitrile (CeO2-PAN) composite sorbent-based (68)Ge/(68)Ga generator reported. This generator used the new CeO2-PAN composite sorbent for preparation of the (68)Ge/(68)Ga generator. Since this sorbent has not been previously evaluated, a thorough long-term evaluation of the performance of the generator is necessary to ensure its applicability for clinical practice. The performance of the generator was evaluated in terms of (68)Ga yield, (68)Ge breakthrough, radioactive concentration of the (68)Ga solution, and suitability of the (68)Ga for the preparation of (68)Ga-labeled tracers. The (68)Ge/(68)Ga generator was able to provide a (68)Ga activity with consistent yields (>70%) and having acceptable radionuclidic (<10(-4)% of (68)Ge breakthrough), radiochemical, and chemical purities for an extended period of time. The eluted (68)GaCl3 is useful for the majority of the (68)Ga complexation chemistry.

  12. Evaluating a drinking-water waste by-product as a novel sorbent for arsenic.

    PubMed

    Makris, Konstantinos C; Sarkar, Dibyendu; Datta, Rupali

    2006-07-01

    Arsenic (As) carcinogenicity to humans and other living organisms has promulgated extensive research on As treatment technologies with varying levels of success; generally, the most efficient methods come with a significantly higher cost burden and they usually perform better in removing As(V) than As(III) from solution. In the reported study, a novel sorbent, a waste by-product of the drinking-water treatment process, namely, drinking-water treatment residuals (WTRs) were evaluated for their ability to adsorb both As(V) and As(III). Drinking-WTRs can be obtained free-of-charge from drinking-water treatment plants, and they have been successfully used to reduce soluble phosphorus (P) concentrations in poorly P-sorbing soils. Phosphate and arsenate molecules have the same tetrahedral geometry, and they chemically behave in a similar manner. We hypothesized that the WTRs would be effective sorbents for both As(V) and As(III) species. Two WTRs (one Fe- and one Al-based) were used in batch experiments to optimize the maximum As(V) and As(III) sorption capacities, utilizing the effects of solid:solution ratios and reaction kinetics. Results showed that both WTRs exhibited high affinities for soluble As(V) and As(III), exhibiting Freundlich type adsorption with no obvious plateau after 2-d of reaction (15000 mg kg-1). The Al-WTR was highly effective in removing both As(V) and As(III), although As(III) removal was much slower. The Fe-WTR showed greater affinity for As(III) than for As(V) and reached As(III) sorption capacity levels similar to those obtained with the Al-WTR-As(V) system (15000 mg kg-1). Arsenic sorption kinetics were biphasic, similar to what has been observed with P sorption by the WTRs. Minimal (<3%) desorption of sorbed As(III) and As(V) was observed, using phosphate as the desorbing ligand. Dissolved Fe2+ concentrations measured during As(III) sorption were significantly correlated (r2=0.74, p<0.005) with the amount of As(III) sorbed by the Fe

  13. Evaluating a drinking-water waste by-product as a novel sorbent for arsenic.

    PubMed

    Makris, Konstantinos C; Sarkar, Dibyendu; Datta, Rupali

    2006-07-01

    Arsenic (As) carcinogenicity to humans and other living organisms has promulgated extensive research on As treatment technologies with varying levels of success; generally, the most efficient methods come with a significantly higher cost burden and they usually perform better in removing As(V) than As(III) from solution. In the reported study, a novel sorbent, a waste by-product of the drinking-water treatment process, namely, drinking-water treatment residuals (WTRs) were evaluated for their ability to adsorb both As(V) and As(III). Drinking-WTRs can be obtained free-of-charge from drinking-water treatment plants, and they have been successfully used to reduce soluble phosphorus (P) concentrations in poorly P-sorbing soils. Phosphate and arsenate molecules have the same tetrahedral geometry, and they chemically behave in a similar manner. We hypothesized that the WTRs would be effective sorbents for both As(V) and As(III) species. Two WTRs (one Fe- and one Al-based) were used in batch experiments to optimize the maximum As(V) and As(III) sorption capacities, utilizing the effects of solid:solution ratios and reaction kinetics. Results showed that both WTRs exhibited high affinities for soluble As(V) and As(III), exhibiting Freundlich type adsorption with no obvious plateau after 2-d of reaction (15000 mg kg-1). The Al-WTR was highly effective in removing both As(V) and As(III), although As(III) removal was much slower. The Fe-WTR showed greater affinity for As(III) than for As(V) and reached As(III) sorption capacity levels similar to those obtained with the Al-WTR-As(V) system (15000 mg kg-1). Arsenic sorption kinetics were biphasic, similar to what has been observed with P sorption by the WTRs. Minimal (<3%) desorption of sorbed As(III) and As(V) was observed, using phosphate as the desorbing ligand. Dissolved Fe2+ concentrations measured during As(III) sorption were significantly correlated (r2=0.74, p<0.005) with the amount of As(III) sorbed by the Fe

  14. Sorbent Testing for the Solidification of Organic Process Waste streams from the Radiochemical Engineering Development Center at Oak Ridge National Laboratory

    SciTech Connect

    Bickford, J.; Foote, M.; Taylor, P.

    2008-07-01

    The U.S. Department of Energy (DOE) has tasked MSE Technology Applications, Inc. (MSE) with evaluating various sorbents to solidify the radioactive liquid organic waste from the Radiochemical Engineering Development Center (REDC) at Oak Ridge National Laboratory (ORNL). REDC recovers and purifies heavy elements (berkelium, californium, einsteinium, and fermium) from irradiated targets for research and industrial applications. Both aqueous and organic waste streams are discharged from REDC. Organic waste is generated from the plutonium/uranium extraction (PUREX), Cleanex, and Pubex processes.1 The PUREX waste derives from an organic-aqueous isotope separation process for plutonium and uranium fission products, the Cleanex waste derives from the removal of fission products and other impurities from the americium/curium product, and the Pubex waste is derived from the separation process of plutonium from dissolved targets. An aqueous waste stream is also produced from these separation processes. MSE has been tasked to test a grouting formula for the aqueous waste stream that includes specially formulated radioactive shielding materials developed by Science and Technology Applications, LLC. This paper will focus on the sorbent testing work. Based on work performed at Savannah River Site (SRS) (Refs. 1, 2), ORNL tested and evaluated three sorbents capable of solidifying the PUREX, Pubex, and Cleanex waste streams and a composite of the three organic waste streams: Imbiber Beads{sup R} IMB230301 (Imbiber Beads), Nochar A610 Petro Bond, and Petroset II Granular{sup TM} (Petroset II-G). Surrogates of the PUREX, Pubex, Cleanex, and a composite organic waste were used for the bench-scale testing. Recommendations resulting from the ORNL testing included follow-on testing by MSE for two of the three sorbents: Nochar Petro Bond and Petroset II-G. MSE recommended that another clay sorbent, Organoclay BM-QT-199, be added to the test sequence. The sorbent/surrogate combinations

  15. Development of novel copper-based sorbents for hot gas cleanup. Technical report, December 1, 1992--February 28, 1993

    SciTech Connect

    Hill, A.H.; Abbasian, J.; Flytzani-Stephanopoulos, M.; Bo, L.; Li, Li.; Honea, F.I.

    1993-05-01

    The objective of this investigation is to evaluate two novel copper-based sorbents (i.e. copper-chromium and copper-cerium) for their effectiveness in removing hydrogen sulfide from fuel gas in the temperature range of 650{degree} to 850{degree}C. New sorbent compositions from the selected Cu-Cr-O and Cu-Ce-O binary oxides were prepared and characterized by BET N{sub 2}-desorption surface area measurement following various calcination/time-temperature exposures. The general trends reported last quarter (on 11 different compositions) were validated this quarter in that both binary oxides lose surface area as the amount of CuO is increased. Time-resolved sulfidation tests were conducted at 850{degree}C using the equimolar CuO.Cr{sub 2}O{sub 3} composition. The two selected binary oxides prepared in larger qauntities (for testing in a two-inch reactor) have physical properties typical of the sorbents prepared in past programs. Two multicycle desulfurization tests, conducted this quarter on the Cu-Ce-O sorbent at 850{degree}C, using a feed gas containing 5000 ppm H{sub 2}S, 10 vol % H{sub 2} and 10 vol % H{sub 2}O at a space velocity (STP) of 2000 h{sup {minus}1}, demonstrated high sulfur removal efficiency for the first one or two cycles, and a significant reduction in efficiency in the following cycles.

  16. Development of novel copper-based sorbents for hot-gas cleanup. [Quarterly] technical report, September 1--November 30, 1993

    SciTech Connect

    Abbasian, J.; Hill, A.H.; Flytzani-Stephanopoulos, M.; Li Li

    1994-03-01

    The objective of this investigation is to evaluate two novel copper-based sorbents, namely copper-chromium and copper-cerium, for their effectiveness in removing hydrogen sulfide from fuel gas in the temperature range of 650{degree} to 850{degree}C. Such high temperatures will be required for the new generation of gas turbines (inlet >750{degree}C) in Integrated Gasification Combined Cycle (IGCC) systems. The effect of pre-reduction on the performance of the sorbents as well as the rate of different reactions occurring in cyclic sulfidation/regeneration, were studied in a thermogravimetric analyzer (TGA). Sulfidation was conducted with and without H{sub 2} and H{sub 2}O, and with and without pre-reduction in H{sub 2} or H{sub 2}/H{sub 2}O. The results of these tests indicate that reduction and regeneration of both sorbents occurs rapidly. Sulfidation of CuCr{sub 2}O{sub 4}, in H{sub 2}O-free and H{sub 2}-/H{sub 2}O-free gas indicates the possible sulfidation of both copper and chromium. Small quantities of SO{sub 2}, were released during sulfidation suggesting the possible oxidation of H{sub 2}S by the sorbent. Regeneration of the CuCr{sub 2}O{sub 4} was complete while regeneration of the CuO-CeO{sub 2} indicated possible limited sulfate formation.

  17. Development of novel copper-based sorbents for hot-gas cleanup. [Quarterly] technical report, March 1, 1993--May 31, 1993

    SciTech Connect

    Hill, A.H.; Abbasian, J.; Flytzani-Stephanopoulos, M.; Li, Li

    1993-09-01

    The objective of this investigation is to evaluate two novel copper-based sorbents (i.e. copper-chromium and copper-cerium) for their effectiveness in removing hydrogen sulfide from fuel gas in the temperature range of 650{degrees} to 850{degrees}C. In this program, structural and kinetic studies are conducted on various compositions of the two selected copper-based sorbents to determine the optimum sorbent composition. The effect of operating conditions on the performance of the sorbents alone with the stability and regenerability of the selected sorbents in successive sulfidation/regeneration operation are determined. Parametric multicycle desulfurization tests were conducted this quarter in a bench-scale (5-cm-diameter) quartz reactor at one atmosphere using the CuCr{sub 2}O{sub 4} and CuO/CeO{sub 2} sorbents. The parameters studied included temperature, space velocity, and feed gas composition. Both sorbents were able to reduce the H{sub 2}S concentration of the reactor feed gas to <10 ppM under all conditions tested. The apparent reactivity of the CuO/CeO{sub 2} sorbent was lower after the first cycle which may be attributed to incomplete regeneration caused by sulfate formation.

  18. Development of Fly Ash Derived Sorbents to Capture CO2 from Flue Gas of Power Plants

    SciTech Connect

    M. Mercedes Maroto-Valer; John M. Andresen; Yinzhi Zhang; Zhe Lu

    2003-12-31

    This research program focused on the development of fly ash derived sorbents to capture CO{sub 2} from power plant flue gas emissions. The fly ash derived sorbents developed represent an affordable alternative to existing methods using specialized activated carbons and molecular sieves, that tend to be very expensive and hinder the viability of the CO{sub 2} sorption process due to economic constraints. Under Task 1 'Procurement and characterization of a suite of fly ashes', 10 fly ash samples, named FAS-1 to -10, were collected from different combustors with different feedstocks, including bituminous coal, PRB coal and biomass. These samples presented a wide range of LOI value from 0.66-84.0%, and different burn-off profiles. The samples also spanned a wide range of total specific surface area and pore volume. These variations reflect the difference in the feedstock, types of combustors, collection hopper, and the beneficiation technologies the different fly ashes underwent. Under Task 2 'Preparation of fly ash derived sorbents', the fly ash samples were activated by steam. Nitrogen adsorption isotherms were used to characterize the resultant activated samples. The cost-saving one-step activation process applied was successfully used to increase the surface area and pore volume of all the fly ash samples. The activated samples present very different surface areas and pore volumes due to the range in physical and chemical properties of their precursors. Furthermore, one activated fly ash sample, FAS-4, was loaded with amine-containing chemicals (MEA, DEA, AMP, and MDEA). The impregnation significantly decreased the surface area and pore volume of the parent activated fly ash sample. Under Task 3 'Capture of CO{sub 2} by fly ash derived sorbents', sample FAS-10 and its deashed counterpart before and after impregnation of chemical PEI were used for the CO{sub 2} adsorption at different temperatures. The sample FAS-10 exhibited a CO{sub 2} adsorption capacity of 17

  19. Evaluation, Not Development Evaluation

    ERIC Educational Resources Information Center

    Carden, Fred

    2013-01-01

    Much has been said in literature about the changing face of development and the changing face of the aid industry. However, the focus of this article is the effect that this could have on evaluation and what might be done to move evaluation into the most useful space possible. Herein, the author makes the case that the evaluation community needs…

  20. Development of Superior Sorbents for Separation of CO2 from Flue Gas at a Wide Temperature range during Coal Combustion

    SciTech Connect

    Panagiotis Smirniotis

    2002-09-17

    A number basic sorbents based on CaO were synthesized, characterized with novel techniques and tested for sorption of CO{sub 2} and selected gas mixtures simulating flue gas from coal fired boilers. Our studies resulted in highly promising sorbents which demonstrated zero affinity for N{sub 2}, O{sub 2}, SO{sub 2}, and NO very low affinity for water, ultrahigh CO{sub 2} sorption capacities, and rapid sorption characteristics, CO{sub 2} sorption at a very wide temperature range, durability, and low synthesis cost. One of the 'key' characteristics of the proposed materials is the fact that we can control very accurately their basicity (optimum number of basic sites of the appropriate strength) which allows for the selective chemisorption of CO{sub 2} at a wide range of temperatures. These unique characteristics of this family of sorbents offer high promise for development of advanced industrial sorbents for the effective CO{sub 2} removal.

  1. Topical Report 5: Sorbent Performance Report

    SciTech Connect

    Krutka, Holly; Sjostrom, Sharon

    2011-05-31

    ADA-ES has completed an extensive sorbent screening program funded primarily through DOE NETL cooperative agreement DE-NT0005649 with support from EPRI and industry cost-share participants. Tests were completed on simulated and actual flue gas. The overall project objective is to address the viability and accelerate development of a solid-based postcombustion CO2 capture technology that can be retrofit to the existing fleet of coal-fired power plants. An important component of the viability assessment was to evaluate the state of development of sorbents and measure key performance characteristics under realistic operating conditions.

  2. Enhanced durability of high-temperature desulfurization sorbents for moving-bed applications. Base Program: Development and testing of zinc ferrite sorbents

    SciTech Connect

    Ayala, R.E.

    1991-08-01

    The objective of this contract was to identify and test fabrication methods and sorbent chemical compositions that enhance the long-term chemical reactivity and mechanical strength of zinc ferrite and other novel sorbents for moving-bed, high-temperature desulfurization of coal-derived gases. Desired properties to be enhanced for moving-bed sorbent materials are: (1) high chemical reactivity (sulfur absorption rate and total sulfur capacity), (2) high mechanical strength (pellet crush strength and attrition resistance), and (3) suitable pellet morphology (e.g., pellet size, shape, surface area, and average specific pore volume). In addition, it is desired to maintain the sorbent properties over extended cyclic use in moving- bed systems.

  3. Development of a Dry Sorbent-based Post-Combustion CO2 Capture Technology for Retrofit in Existing Power Plants

    SciTech Connect

    Nelson, Thomas; Coleman, Luke; Anderson, Matthew; Gupta, Raghubir; Herr, Joshua; Kalluri, Ranjeeth; Pavani, Maruthi

    2009-12-31

    The objective of this research and development (R&D) project was to further the development of a solid sorbent-based CO2 capture process based on sodium carbonate (i.e. the Dry Carbonate Process) that is capable of capturing>90% of the CO2 as a nearly pure stream from coal-fired power plant flue gas with <35% increase in the cost of electrictiy (ICOE).

  4. Evaluation of polycaprolactone as a new sorbent coating for determination of polar organic compounds in water samples using membrane-SPME.

    PubMed

    Marcinkowski, Łukasz; Kloskowski, Adam; Spietelun, Agata; Namieśnik, Jacek

    2015-02-01

    Commercially available solid-phase microextraction fibers used for isolation of polar analytes are based on the adsorption phenomenon. In consequence, typical limitations bonded with analytes displacement and matrix effects are very frequent. In the present study, alternative solution is described. Polycaprolactone (PCL) was used for the first time as sorbent to isolate polar organic compounds from water samples using the membrane-solid-phase microextraction (M-SPME) technique. In this technique, due to protective role of the mechanically and thermally stable polydimethylsiloxane (PDMS) membrane, internal polar coating might be melted during extraction and desorption of analytes. In consequence sorbents with low melting points like a PCL might be utilized. Based on chromatographic retention data, triazines were selected as a model compounds for evaluation of the sorptive properties of the polycaprolactone. Applying the screening plan and central composite design, statistically significant parameters influencing extraction efficiency were determined and optimized. The analysis of variance confirmed the significant influence of temperature, salt content, and pH of samples on the extraction efficiency. Besides the new PCL/PDMS fiber, a commercial fiber coated with divinylbenzene/polydimethylsiloxane (DVB/PDMS) was used for comparative studies. The results obtained showed that PCL is an interesting sorbent which can be successfully applied for isolation of polar organics from aqueous matrices at a broad range of analytes concentration. The determined detection limits of procedure based on the novel fiber enable its application at the concentration levels of triazines recommended by the US EPA standards. The practical applicability of the developed fiber has been confirmed by the results based on the analysis of real samples.

  5. Design and Development of New Carbon-Based Sorbent Systems for an Effective Containment of Hydrogen

    SciTech Connect

    Alan C. Cooper

    2012-05-03

    This is a summary for work performed under cooperative agreement DE FC36 04GO14006 (Design and Development of New Carbon-based Sorbent Systems for an Effective Containment of Hydrogen). The project was directed to discover new solid and liquid materials that use reversible catalytic hydrogenation as the mechanism for hydrogen capture and storage. After a short period of investigation of solid materials, the inherent advantages of storing and transporting hydrogen using liquid-phase materials focused our attention exclusively on organic liquid hydrogen carriers (liquid carriers). While liquid carriers such as decalin and methylcyclohexane were known in the literature, these carriers suffer from practical disadvantages such as the need for very high temperatures to release hydrogen from the carriers and difficult separation of the carriers from the hydrogen. In this project, we were successful in using the prediction of reaction thermodynamics to discover liquid carriers that operate at temperatures up to 150 C lower than the previously known carriers. The means for modifying the thermodynamics of liquid carriers involved the use of certain molecular structures and incorporation of elements other than carbon into the carrier structure. The temperature decrease due to the more favorable reaction thermodynamics results in less energy input to release hydrogen from the carriers. For the first time, the catalytic reaction required to release hydrogen from the carriers could be conducted with the carrier remaining in the liquid phase. This has the beneficial effect of providing a simple means to separate the hydrogen from the carrier.

  6. DEVELOPMENT OF A CALCIUM-BASED SORBENT FOR HOT GAS CLEANUP

    SciTech Connect

    T.D. Wheelock; L.K. Doraiswamy; K. Constant

    1999-10-01

    The development and testing of potential calcium-based sorbents for hot gas cleanup continued. One of the most promising materials combines powdered limestone and a calcium aluminate cement by two step pelletization followed by steam curing. Reasonably strong pellets are produced with good adsorption characteristics by incorporating 20 wt.% cement in the core and 40 wt.% cement in the shell. The resulting 4.76 mm diameter pellets are capable of withstanding a crushing force approaching 11.5 N/mm before breaking and are also capable of removing H{sub 2}S from dilute, hot gas streams. The pellets are also regenerable and reusable. Another promising material combines calcium carbonate powder and finely ground calcined alumina in tablet form. The small tablets are prepared by mixing the materials with water to form a thick paste which is then molded and dried. The tablets are hardened by calcining at either 1000 to 1100 C. The resulting tablets are strong and capable of removing H{sub 2}S from a dilute, hot gas stream.

  7. Sorbent Testing For Solidification of Process Waste streams from the Radiochemical Engineering Development Center at Oak Ridge National Laboratory

    SciTech Connect

    Bickford, J.; Taylor, P.

    2007-07-01

    The U.S. Department of Energy (DOE) tasked MSE Technology Applications, Inc. (MSE) to evaluate sorbents identified by Oak Ridge National Laboratory (ORNL) to solidify the radioactive liquid organic waste from the Radiochemical Engineering Development Center (REDC) at ORNL. REDC recovers and purifies heavy elements (berkelium, californium, einsteinium, and fermium) from irradiated targets for research and industrial applications. Both organic and aqueous waste streams are discharged from REDC. The organic waste is generated from the plutonium/uranium extraction (Purex), Cleanex, and Pubex processes. The Purex waste derives from an organic-aqueous isotope separation process for plutonium and uranium fission products, the Cleanex waste derives from the removal of fission products and other impurities from the americium/curium product, and the Pubex waste is derived from the separation process of plutonium from dissolved targets. MSE had also been tasked to test a grouting formula for the aqueous waste stream that includes radioactive shielding material. The aqueous waste is a mixture of the raffinate streams from the various extraction processes plus the caustic solution that is used to dissolve the aluminum cladding from the irradiated targets. (authors)

  8. CaO-based CO2 sorbents: from fundamentals to the development of new, highly effective materials.

    PubMed

    Kierzkowska, Agnieszka M; Pacciani, Roberta; Müller, Christoph R

    2013-07-01

    The enormous anthropogenic emission of the greenhouse gas CO2 is most likely the main reason for climate change. Considering the continuing and indeed growing utilisation of fossil fuels for electricity generation and transportation purposes, development and implementation of processes that avoid the associated emissions of CO2 are urgently needed. CO2 capture and storage, commonly termed CCS, would be a possible mid-term solution to reduce the emissions of CO2 into the atmosphere. However, the costs associated with the currently available CO2 capture technology, that is, amine scrubbing, are prohibitively high, thus making the development of new CO2 sorbents a highly important research challenge. Indeed, CaO, readily obtained through the calcination of naturally occurring limestone, has been proposed as an alternative CO2 sorbent that could substantially reduce the costs of CO2 capture. However, one of the major drawbacks of using CaO derived from natural sources is its rapidly decreasing CO2 uptake capacity with repeated carbonation-calcination reactions. Here, we review the current understanding of fundamental aspects of the cyclic carbonation-calcination reactions of CaO such as its reversibility and kinetics. Subsequently, recent attempts to develop synthetic, CaO-based sorbents that possess high and cyclically stable CO2 uptakes are presented. PMID:23821467

  9. Preliminary carbon dioxide capture technical and economic feasibility study evaluation of carbon dioxide capture from existing fired plants by hybrid sorption using solid sorbents

    SciTech Connect

    Benson, Steven; Envergex, Srivats; Browers, Bruce; Thumbi, Charles

    2013-01-01

    Barr Engineering Co. was retained by the Institute for Energy Studies (IES) at University of North Dakota (UND) to conduct a technical and economic feasibility analysis of an innovative hybrid sorbent technology (CACHYS™) for carbon dioxide (CO2) capture and separation from coal combustion–derived flue gas. The project team for this effort consists of the University of North Dakota, Envergex LLC, Barr Engineering Co., and Solex Thermal Science, along with industrial support from Allete, BNI Coal, SaskPower, and the North Dakota Lignite Energy Council. An initial economic and feasibility study of the CACHYS™ concept, including definition of the process, development of process flow diagrams (PFDs), material and energy balances, equipment selection, sizing and costing, and estimation of overall capital and operating costs, is performed by Barr with information provided by UND and Envergex. The technology—Capture from Existing Coal-Fired Plants by Hybrid Sorption Using Solid Sorbents Capture (CACHYS™)—is a novel solid sorbent technology based on the following ideas: reduction of energy for sorbent regeneration, utilization of novel process chemistry, contactor conditions that minimize sorbent-CO2 heat of reaction and promote fast CO2 capture, and a low-cost method of heat management. The technology’s other key component is the use of a low-cost sorbent.

  10. Developing sorbent standards for spill response: Effects of the Oil Pollution Act of 1990 and the Free Trade Agreement

    NASA Astrophysics Data System (ADS)

    Schrader, E. L.; Westover, E. S.

    1993-09-01

    For the past five years the Millsaps Sorbent Laboratory has been actively engaged in developing standards for initial and long-term oil spill remedial technologies. As a voting member of the American Society of Testing Materials (ASTM) F-20 Committee, Canadian General Standards Board, and the US Coast Guard Sorbents Task Force, the laboratory has been engaged in developing useful, pragmatic protocols for various chemical and physical sorbent and filtration technologies driven by the deadlines imposed by the Oil Pollution Act of 1990 (OPA 90). The “open border” approach to certification of technologies and products promulgated by the US/Canadian Free Trade Agreement has placed the US users and producers of such products and systems in a unique and tenuous position. Canadian standards and goals are grandfathered into the United States under this agreement and products have official US government certification based on Canadian regulations. This situation is unfavorable to the US domestic environment and economy for several specific scenarios. Included in these scenarios are: abundant warmwater zones and inland waters of the US versus Canada, the basic chemical variation between Canadian and US crude oils, the different generally accepted remediation technologies in the US versus Canadian, and the technology validation procedures prior to purchase inherent to both countries.

  11. Carbon sorbent based on flax boon

    SciTech Connect

    Abramov, M.V.; Tyulina, R.M.; Yaroslavtsev, V.T.

    1994-11-10

    Flax-fiber production wastes such as boon can be used effectively as the starting material for producing carbon sorbents. Activated carbons are among the most widely used sorbents in industrial wastewater and waste gas treatment. A single-stage process has been developed for producing an efficient, cheap carbon sorbent based on flax boon.

  12. Subtask 4.27 - Evaluation of the Multielement Sorbent Trap (MEST) Method at an Illinois Coal-Fired Plant

    SciTech Connect

    Pavlish, John; Thompson, Jeffrey; Dunham, Grant

    2014-09-30

    Owners of fossil fuel-fired power plants face the challenge of measuring stack emissions of trace metals and acid gases at much lower levels than in the past as a result of increasingly stringent regulations. In the United States, the current reference methods for trace metals and halogens are wet-chemistry methods, U.S. Environmental Protection Agency (EPA) Methods 29 and 26 or 26A, respectively. As a possible alternative to the EPA methods, the Energy & Environmental Research Center (EERC) has developed a novel multielement sorbent trap (MEST) method to be used to sample for trace elements and/or halogens. Sorbent traps offer a potentially advantageous alternative to the existing sampling methods, as they are simpler to use and do not require expensive, breakable glassware or handling and shipping of hazardous reagents. Field tests comparing two sorbent trap applications (MEST-H for hydrochloric acid and MEST-M for trace metals) with the reference methods were conducted at two power plant units fueled by Illinois Basin bituminous coal. For hydrochloric acid, MEST measured concentrations comparable to EPA Method 26A at two power plant units, one with and one without a wet flue gas desulfurization scrubber. MEST-H provided lower detection limits for hydrochloric acid than the reference method. Results from a dry stack unit had better comparability between methods than results from a wet stack unit. This result was attributed to the very low emissions in the latter unit, as well as the difficulty of sampling in a saturated flue gas. Based on these results, the MEST-H sorbent traps appear to be a good candidate to serve as an alternative to Method 26A (or 26). For metals, the MEST trap gave lower detection limits compared to EPA Method 29 and produced comparable data for antimony, arsenic, beryllium, cobalt, manganese, selenium, and mercury for most test runs. However, the sorbent material produced elevated blanks for cadmium, nickel, lead, and chromium at levels

  13. Evaluation of Commercial Off-the-Shelf Sorbents and Catalysts for Control of Ammonia and Carbon Monoxide

    NASA Technical Reports Server (NTRS)

    Luna, Bernadette; Somi, George; Winchester, J. Parker; Grose, Jeffrey; Mulloth, Lila; Perry, Jay L.

    2013-01-01

    Designers of future space vehicles envision simplifying the Atmosphere Revitalization (AR) system by combining the functions of trace contaminant (TC) control and carbon dioxide removal into one swing-bed system. Flow rates and bed sizes of the TC and CO2 systems have historically been very different. There is uncertainty about the ability of trace contaminant sorbents to adsorb adequately in high-flow or short bed length configurations, and to desorb adequately during short vacuum exposures. There is also concern about ambient ammonia levels in the absence of a condensing heat exchanger. In addition, new materials and formulations have become commercially available, formulations never evaluated by NASA for purposes of trace contaminant control. The optimal air revitalization system for future missions may incorporate a swing-bed system for carbon dioxide (CO2) and partial trace contaminant control, with a reduced-size, low-power, targeted trace contaminant system supplying the remaining contaminant removal capability. This paper describes the results of a comparative experimental investigation into materials for trace contaminant control that might be part of such a system. Ammonia sorbents and low temperature carbon monoxide (CO) oxidation catalysts are the foci. The data will be useful to designers of AR systems for future flexible path missions. This is a continuation of work presented in a prior year, with extended test results.

  14. Evaluation of Commercial Off-the-Shelf Sorbents and Catalysts for Control of Ammonia and Carbon Monoxide

    NASA Technical Reports Server (NTRS)

    Luna, Bernadette; Somi, George; Winchester, J. Parker; Grose, Jeffrey; Mulloth, Lila; Perry, Jay L.

    2010-01-01

    Designers of future space vehicles envision simplifying the Atmosphere Revitalization (AR) system by combining the functions of trace contaminant (TC) control and carbon dioxide removal into one swing-bed system. Flow rates and bed sizes of the TC and CO2 systems have historically been very different. There is uncertainty about the ability of trace contaminant sorbents to adsorb adequately in high-flow or short bed length configurations, and to desorb adequately during short vacuum exposures. There is also concern about ambient ammonia levels in the absence of a condensing heat exchanger. In addition, new materials and formulations have become commercially available, formulations never evaluated by NASA for purposes of trace contaminant control. The optimal air revitalization system for future missions may incorporate a swing-bed system for carbon dioxide (CO2) and partial trace contaminant control, with a reduced-size, low-power, targeted trace contaminant system supplying the remaining contaminant removal capability. This paper describes the results of a comparative experimental investigation into materials for trace contaminant control that might be part of such a system. Ammonia sorbents and low temperature carbon monoxide (CO) oxidation catalysts are the foci. The data will be useful to designers of AR systems for future flexible path missions. This is a continuation of work presented in a prior year, with extended test results.

  15. Development of durable mixed-metal oxide sorbents for high-temperature desulfurization of coal gases in moving-bed reactors

    SciTech Connect

    Ayala, R.E.; Jain, S.C.

    1993-06-01

    Mixed-metal oxide sorbents, particularly zinc ferrite and zinc titanate, are being developed for use in hot gas cleanup of coal gas in the integrated gasification combined-cycle (IGCC). For the case of moving-bed systems, the pelletized sorbent moves between the absorber and regenerator as it absorbs H{sub 2}S from coal gas and is regenerated under diluted air. Therefore a mechanically strong and chemically active sorbent is necessary for proper long-term operation of the system. These desired properties depend on the active components in the sorbent, the type and concentration of the binder material, and the sorbent preparation procedure. In the current program, several zinc titanate sorbent formulations have been prepared using a new rounding fabrication procedure, and varying the types of additives/binders (e.g., bentonite and molybdenum) and calcination temperature (1450-1800 {degree}F, 788-982 {degree}C). Comparison with baseline cylindrical formulations was made by measuring attrition resistance, crush strength, thermogravimetric reactivity and bench-scale reactor performance.

  16. Sulfation of calcium based sorbents in a combustion environment

    SciTech Connect

    Newton, G.H.

    1987-01-01

    The capture of SO/sub 2/ by dry, calcium-based sorbents was examined in a three part research effort: (1) an experimental evaluation of sorbent materials under isothermal reaction conditions; (2) characterization of sulfation fundamentals through sulfation rate measurements with sized, precalcined sorbents and the development of a distributed pore sulfation model; and (3) experimental definition of reaction temperature effects and computer modeling of the simultaneous sintering and sulfation processes. The experimental sorbent evaluation examined calcitic and dolomitic carbonates and hydrates. High temperature, isothermal SO/sub 2/ capture data were obtained as a function of Ca/S molar ratio, temperature, and SO/sub 2/ concentration for each sorbent. SO/sub 2/ capture was found to be approximately linearly dependent on Ca/S ratio, relatively insensitive to SO/sub 2/ concentration above 2000 ppM, and a strong function of sorbent type. Time resolved sulfation data of sized, precalcined sorbents indicated that sulfation is initially rapid, but beyond approximately 300 ms the sulfation rate decreases dramatically. A distributed pore model, which viewed CaO particles as composed of nonintersecting, cylindrical pores with diameters determined from nitrogen porosimetry, particle boundary layer, pore, and CaSO/sub 4/ product layer diffusions in addition to the heterogeneous chemical reaction was developed. Temperature dependent sulfation data for precalcined sorbents suggest two types of sintering influence particle porosity: sintering associated with the combustion process and sintering promoted by the presence of sulfate ions in the particle crystal structure. Inclusion of both sintering mechanisms in the distributed pore model allowed predictions of the highest temperature experimental data from a variety of precalcines.

  17. Development of a new peat-based oil sorbent using peat pyrolysis.

    PubMed

    Klavins, Maris; Porshnov, Dmitry

    2013-01-01

    The growing use and transport of crude oil and oil products has led to increasing numbers of oil spillages of various scales. Oil sorbents have been extensively used for remediation of the consequences of such accidents. The aim of this study is to investigate the possible use of peat and its thermal treatment products for oil sorption. Peat as an oil sorbent has poor buoyancy characteristics, relatively low oil sorption capacity and low hydrophobicity. However, thermal treatment (low-temperature pyrolysis and synthesis of peat-based activated coal) helps to significantly improve its sorptive characteristics. Peat is a potential material for oil sorption because it has such advantages as low cost, biodegradability and relatively high parameters of specific surface area and porosity. The processes and structural changes taking place during low-temperature pyrolysis have been studied by means of IR spectroscopy, thermogravimetry and scanning electron microscopy.

  18. Hot gas desulfurization with sorbents containing oxides of zinc, iron, vanadium and copper

    SciTech Connect

    Akyurtlu, A.; Akyurtlu, J.F.

    1992-01-01

    The main objective of this research is to evaluate the desulfurization performance of novel sorbents consisting of different combinations of zinc, iron, vanadium and copper oxides; and to develop a sorbent which can reduce H{sub 2}S levels to less than 1 ppmv, which can stabilize zinc, making operations above 650{degrees}C possible, and which can produce economically recoverable amounts of elemental sulfur during regeneration. This objective will be accomplished by evaluating the sorbent performance using fixed-bed and TGA experiments supported by sorbent characterization at various reaction extents. In the seventh quarter, the screening of the promoted sorbents in the packed bed reactor was continued. The results of this work were presented at the 1992 University Coal Research Contractors, Review Conference at Pittsburgh, PA.

  19. Development and Testing of a Sorbent-Based Atmosphere Revitalization System for the Crew Exploration Vehicle 2007/2008

    NASA Technical Reports Server (NTRS)

    Knox, James C.; Howard, David; Miller, Lee

    2008-01-01

    The design of a Vacuum-Swing Adsorption (VSA) system to remove metabolic water and metabolic carbon dioxide from the Orion Crew Exploration Vehicle (CEV) atmosphere is presented. The approach for Orion is a VSA system that removes not only 100 percent of the metabolic CO2 from the atmosphere, but also 100% of the metabolic water as well, a technology approach that has not been used in previous spacecraft life support systems. The design and development of the Sorbent Based Atmosphere Regeneration (SBAR) system, including test articles, a facility test stand, and full-scale testing in late 2007 and early 2008 is discussed.

  20. Development of new sorbents to remove mercury and selenium from flue gas. Final report, September 1, 1993--August 31, 1994

    SciTech Connect

    Shiao, S.Y.

    1995-02-01

    Mercury (Hg) and selenium (Se) are two of the volatile trace metals in coal, which are often not captured by conventional gas clean up devices of coal-fired boilers. An alternative is to use sorbents to capture the volatile components of trace metals after coal combustion. In this project sorbent screening tests were performed in which ten sorbents were selected to remove metallic mercury in N{sub 2}. These sorbents included activated carbon, char prepared from Ohio No. 5 coal, molecular sieves, silica gel, aluminum oxide, hydrated lime, Wyoming bentonite, kaolin, and Amberite IR-120 (an ion-exchanger). The sorbents were selected based on published information and B&W`s experience on mercury removal. The promising sorbent was then selected and modified for detailed studies of removal of mercury and selenium compounds. The sorbents were tested in a bench-scale adsorption facility. A known amount of each sorbent was loaded in the column as a packed bed. A carrier gas was bubbled through the mercury and selenium compounds. The vaporized species were carried by the gas and went through the sorbent beds. The amount of mercury and selenium compounds captured by the sorbents was determined by atomic absorption. Results are discussed.

  1. Preparation of a new sorbent based on boronate affinity monolith and evaluation of its extraction performance for nitrogen-containing pollutants.

    PubMed

    Hu, Hongyou; Zhang, Yu; Zhang, Yong; Huang, Xiaojia; Yuan, Dongxing

    2014-05-16

    In this study, a new boronate affinity sorbent based on poly(4-vinylphenylboronic acid-divinylbenzene) monolith (VPB-DB) was prepared and used as extractive medium of stir cake sorptive extraction (SCSE). The effect of the preparation parameters in the polymerization mixture on extraction performance was investigated thoroughly. The sorbent was characterized by infrared spectroscopy, elemental analysis, scanning electron microscopy and mercury intrusion porosimetry. The determination of 8 sulfonamides in environmental water samples with the combination of SCSE and high performance liquid chromatography tandem mass spectrometry detection was selected as a paradigm for the evaluation of extraction performance of poly(VPB-DB) monolith for nitrogen-containing pollutants. Under the optimal extraction conditions, the limits of detection (S/N=3) and limits of quantification (S/N=10) for the target analytes were 0.0012-0.010 and 0.0040-0.033μg/L, respectively. The method also showed good linearity, repeatability, recoveries and high feasibility. At the same time, aromatic amines, nitrophenols, amide herbicides and sudan dyes were also used to evaluate the extractive performance of the sorbent for nitrogen-containing compounds. Results well indicate that the interaction of boron-nitrogen coordination between sorbent and analytes plays a key role in the extraction of nitrogen-containing compounds. PMID:24713423

  2. DEVELOPMENT OF A CALCIUM-BASED SORBENT FOR HOT GAS CLEANUP

    SciTech Connect

    T.D. Wheelock; L.K. Doraiswamy; K. Constant

    1999-03-31

    The preparation and testing of potential sorbents for removing H{sub 2}S and COS from hot coal gas continued. Two preparation methods received the most consideration. Both methods involve pelletizing powders in a revolving drum under moist conditions followed either by heat treatment or steam curing to harden the pellets, depending on the particle bonding mechanism. One method was used to pelletize mixtures of calcium carbonate and either alumina or a calcium aluminate cement in a single step. Another method was used to pelletize powdered limestone in an initial step followed by the application of a coating consisting of both limestone and a hydraulic cement in a second step. By employing this method, an especially promising material was produced consisting of a limestone core surrounded by a shell consisting initially of 80 wt.% limestone and 20% wt.% calcium aluminate cement. The best material exhibited both an acceptable crushing strength and adsorption capacity for H{sub 2}S.

  3. Development of novel copper-based sorbents for hot-gas cleanup. [Quarterly] technical report, December 1, 1993--February 28, 1994

    SciTech Connect

    Abbasian, J.; Hill, A.H.; Flytzani-Stephanopoulos, M.; Li, Zhijiang

    1994-06-01

    The objective of this investigation is to evaluate two novel copper-based sorbents, namely copper-chromium and copper-cerium, for their effectiveness in removing hydrogen sulfide from fuel gas in the temperature range of 650{degree} to 850{degree}. Such high temperatures will be required for the new generation of gas turbines (inlet >750{degree}C) in Integrated Gasification Combined Cycle (IGCC) systems. The effect of pre-reduction with H{sub 2}, in the presence of H{sub 2}O on the performance of the sorbents in cyclic sulfidation/regeneration, was studied in a thermogravimetric analyzer (TGA) and in a fixed-bed reactor at 750{degree}C. The results of the TGA tests indicate that pre-reduction of the sorbents is very fast in either 10% or 30% H{sub 2}. Without sorbent pre-reduction, sulfidation consists of two-stages, a reduction-dominating and a sulfidation-dominating stage. Sulfidation apparently takes place before reduction is complete. During regeneration some copper/cerium sulfates may have formed and Cu{sub 2}O may have formed in addition to CuO. The fixed-bed reactor tests show that at 750{degree}C: (1) prereducing the CuO-Cr{sub 2}O{sub 3} with H{sub 2} does not effect the reactivity of the sorbent towards H{sub 2}S at either the high or low H{sub 2} feed gas concentrations and (2) when 30% H{sub 2} was used during sulfidation of either sorbent, the first H{sub 2}S breakthrough occurs earlier than when 10% H{sub 2} was used.

  4. Development of standardized air-blown coal gasifier/gas turbine concepts for future electric power systems. Volume 2, Appendix A: Fixed bed gasifier and sulfur sorbent regeneration subsystem computer model development: Final report

    SciTech Connect

    Blough, E.; Russell, W.; Leach, J.W.

    1990-08-01

    Computer models have been developed for evaluating conceptual designs of integrated coal gasification combined cycle power plants. An overall system model was developed for performing thermodynamic cycle analyses, and detailed models were developed for predicting performance characteristics of fixed bed coal gasifiers and hot gas clean up subsystem components. The overall system model performs mass and energy balances and does chemical equilibrium analyses to determine the effects of changes in operating conditions, or to evaluate proposed design changes. An existing plug flow model for fixed bed gasifiers known as the Wen II model was revised and updated. Also, a spread sheet model of zinc ferrite sulfur sorbent regeneration subsystem was developed. Parametric analyses were performed to determine how performance depends on variables in the system design. The work was done to support CRS Sirrine Incorporated in their study of standardized air blown coal gasifier gas turbine concepts.

  5. Influence of temperature and regeneration cycles on Hg capture and efficiency by structured Au/C regenerable sorbents.

    PubMed

    Ballestero, D; Gómez-Giménez, C; García-Díez, E; Juan, R; Rubio, B; Izquierdo, M T

    2013-09-15

    The objective of this work is to evaluate a novel regenerable sorbent for mercury capture based on gold nanoparticles supported on a honeycomb structured carbon monolith. A new methodology for gold nanoparticles deposition onto carbon monolith support has been developed to obtain an Au sorbent based on the direct reduction of a gold salt onto the carbon material. For comparison purposes, colloidal gold method was also used to obtain Au/C sorbents. Both types of sorbents were characterized by different techniques in order to obtain the bulk gold content, the particle size distribution and the chemical states of gold after deposition. The mercury capture capacity and mercury capture efficiency of sorbents were tested in a bench scale facility at different experimental conditions. The regenerability of the sorbents was tested along several cycles of Hg capture-regeneration. High retention efficiencies are found for both types of sorbents comparing their gold content. Moreover, the high retention efficiency is maintained along several cycles of Hg capture-regeneration. The study of the fresh sorbent, the sorbent after Hg exposition and after regeneration by XPS and XRD gives insight to explain those results.

  6. Kinetics of Mn-based sorbents for hot coal gas desulfurization. Quarterly progress report, July 15, 1995--September 15, 1995

    SciTech Connect

    Hepworth, M.T.

    1995-09-15

    The Morgantown Energy Technology Center (METC) of the U.S. Department of Energy (DOE) is actively pursuing the development of reliable and cost-effective processes to clean coal gasifier gases for application to integrated gasification combined cycle (IGCC) and molten carbonate fuel cell (MCFC) power plants. A large portion of gas cleanup research has been directed towards hot gas desulfurization using Zn-based sorbents. However, zinc titinate sorbents undergo reduction to the metal at temperatures approaching 700{degrees}C. In addition, sulfate formation during regeneration leads to spalling of reactive 293 surfaces. Due to zinc-based sorbent performance, METC has shown interest in formulating and testing manganese-based sorbents. Westmoreland and Harrison evaluated numerous candidate sulfur sorbents and identified Mn as a good candidate. Later, Turkdogan and Olsson tested manganese-based sorbents which demonstrated superior desulfurization capacity under high temperatures, and reducing conditions. Recently, Ben-Slimane and Hepworth conducted several studies on formulating Mn-sorbents and desulfurizing a simulated fuel gas. Although thermodynamics predicts higher over-pressures with Mn verses Zn, under certain operating conditions Mn-based sorbents may obtain < 20 ppmv. In addition, the manganese-sulfur-oxygen (Mn-S-O) system does not reduce to the metal under even highly reducing gases at high temperatures (550-900{degrees}C). Currently, many proposed IGCC processes include a water quench prior to desulfurization. This is for two reasons; limitations in the process hardware (1000{degrees}C), and excessive Zn-based sorbent loss (about 700{degrees}C). With manganese the water quench is obviated due to sorbent loss, as Mn-based sorbents have been shown to retain reactivity under cycling testing at 900{degrees}C. This reduces system hardware, and increases thermal efficiency while decreasing the equilibrium H{sub 2}S over-pressure obtainable with a manganese sorbent.

  7. Development and testing of inorganic sorbents made by the internal gelation process for radionuclide and heavy metal separations

    SciTech Connect

    Egan, B.Z.; Collins, J.L.; Anderson, K.K.; Chase, C.W.

    1995-11-29

    The objectives of this task are to develop, prepare, and test microspheres and granular forms of inorganic ion exchangers to remove radionuclides and heavy metals from waste streams occurring at various sites. Several inorganic materials, such as hexacyanoferrates, titanates, phosphates, and oxides have high selectivities and efficiencies for separating and removing radionuclides such as uranium, technetium, cesium, and strontium, and metals such as cobalt, silver, zinc, and zirconium from aqueous waste streams. However, these sorbents frequently exist only as powders and consequently are not readily adaptable to continuous processing such as column chromatography. Making these inorganic ion exchangers as microspheres or granular forms improves the flow dynamics for column operations and expands their practical applications. Microspheres of several materials have been prepared at ORNL, and the effectiveness of zirconium monohydrogen phosphate and hydrous titanium oxide microspheres for removing radionuclides from hot cell waste solutions has been demonstrated.

  8. Simultaneous control of Hg0, SO2, and NOx by novel oxidized calcium-based sorbents.

    PubMed

    Ghorishi, S Behrooz; Singer, Carl F; Jozewicz, Wojciech S; Sedman, Charles B; Srivastava, Ravi K

    2002-03-01

    Efforts to develop multipollutant control strategies have demonstrated that adding certain oxidants to different classes of Ca-based sorbents leads to a significant improvement in elemental Hg vapor (Hg0), SO2, and NOx removal from simulated flue gases. In the study presented here, two classes of Ca-based sorbents (hydrated limes and silicate compounds) were investigated. A number of oxidizing additives at different concentrations were used in the Ca-based sorbent production process. The Hg0, SO2, and NOx capture capacities of these oxidant-enriched sorbents were evaluated and compared to those of a commercially available activated carbon in bench-scale, fixed-bed, and fluid-bed systems. Calcium-based sorbents prepared with two oxidants, designated C and M, exhibited Hg0 sorption capacities (approximately 100 microg/g) comparable to that of the activated carbon; they showed far superior SO2 and NOx sorption capacities. Preliminary cost estimates for the process utilizing these novel sorbents indicate potential for substantial lowering of control costs, as compared with other processes currently used or considered for control of Hg0, SO2, and NOx emissions from coal-fired boilers. The implications of these findings toward development of multipollutant control technologies and planned pilot and field evaluations of more promising multipollutant sorbents are summarily discussed.

  9. Hot gas desulfurization with sorbents containing oxides of zinc, iron, vanadium and copper. Quarterly technical progress report, July 1992

    SciTech Connect

    Akyurtlu, A.; Akyurtlu, J.F.

    1992-09-01

    The main objective of this research is to evaluate the desulfurization performance of novel sorbents consisting of different combinations of zinc, iron, vanadium and copper oxides; and to develop a sorbent which can reduce H{sub 2}S levels to less than 1 ppmv, which can stabilize zinc, making operations above 650{degrees}C possible, and which can produce economically recoverable amounts of elemental sulfur during regeneration. This objective will be accomplished by evaluating the sorbent performance using fixed-bed and TGA experiments supported by sorbent characterization at various reaction extents. In the seventh quarter, the screening of the promoted sorbents in the packed bed reactor was continued. The results of this work were presented at the 1992 University Coal Research Contractors, Review Conference at Pittsburgh, PA.

  10. Full-scale evaluation of mercury control with sorbent injection and COHPAC at Alabama Power E.C. Gaston.

    PubMed

    Bustard, C Jean; Durham, Michael; Lindsey, Charles; Starns, Travis; Baldrey, Ken; Martin, Cameron; Schlager, Richard; Sjostrom, Sharon; Slye, Rick; Renninger, Scott; Monroe, Larry; Miller, Richard; Chang, Ramsay

    2002-08-01

    The overall objective of this project was to determine the cost and impacts of Hg control using sorbent injection into a Compact Hybrid Particulate Collector (COHPAC) at Alabama Power's Gaston Unit 3. This test is part of a program funded by the U.S. Department of Energy's National Energy Technology Laboratory (NETL) to obtain the necessary information to assess the costs of controlling Hg from coal-fired utility plants that do not have scrubbers for SO2 control. The economics will be developed based on various levels of Hg control. Gaston Unit 3 was chosen for testing because COHPAC represents a cost-effective retrofit option for utilities with existing electrostatic precipitators (ESPs). COHPAC is an EPRI-patented concept that places a high air-to-cloth ratio baghouse downstream of an existing ESP to improve overall particulate collection efficiency. Activated carbons were injected upstream of COHPAC and downstream of the ESP to obtain performance and operational data. Results were very encouraging, with up to 90% removal of Hg for short operating periods using powdered activated carbon (PAC). During the long-term tests, an average Hg removal efficiency of 78% was measured. The PAC injection rate for the long-term tests was chosen to maintain COHPAC cleaning frequency at less than 1.5 pulses/bag/hr. PMID:12184690

  11. Full-scale evaluation of mercury control with sorbent injection and COHPAC at Alabama Power E.C. Gaston.

    PubMed

    Bustard, C Jean; Durham, Michael; Lindsey, Charles; Starns, Travis; Baldrey, Ken; Martin, Cameron; Schlager, Richard; Sjostrom, Sharon; Slye, Rick; Renninger, Scott; Monroe, Larry; Miller, Richard; Chang, Ramsay

    2002-08-01

    The overall objective of this project was to determine the cost and impacts of Hg control using sorbent injection into a Compact Hybrid Particulate Collector (COHPAC) at Alabama Power's Gaston Unit 3. This test is part of a program funded by the U.S. Department of Energy's National Energy Technology Laboratory (NETL) to obtain the necessary information to assess the costs of controlling Hg from coal-fired utility plants that do not have scrubbers for SO2 control. The economics will be developed based on various levels of Hg control. Gaston Unit 3 was chosen for testing because COHPAC represents a cost-effective retrofit option for utilities with existing electrostatic precipitators (ESPs). COHPAC is an EPRI-patented concept that places a high air-to-cloth ratio baghouse downstream of an existing ESP to improve overall particulate collection efficiency. Activated carbons were injected upstream of COHPAC and downstream of the ESP to obtain performance and operational data. Results were very encouraging, with up to 90% removal of Hg for short operating periods using powdered activated carbon (PAC). During the long-term tests, an average Hg removal efficiency of 78% was measured. The PAC injection rate for the long-term tests was chosen to maintain COHPAC cleaning frequency at less than 1.5 pulses/bag/hr.

  12. Evaluation of kapok (Ceiba pentandra (L.) Gaertn.) as a natural hollow hydrophobic-oleophilic fibrous sorbent for oil spill cleanup.

    PubMed

    Lim, Teik-Thye; Huang, Xiaofeng

    2007-01-01

    Oil sorption capacity and hydrophobic-oleophilic characteristics of an agricultural product, kapok (Ceiba pentandra), was thoroughly examined. The kapok fiber has a hollow structure with large lumen. Its performance was compared with that of a polypropylene (PP), a widely used commercial oil sorbent for oil spill cleanup. The oils investigated were diesel, hydraulic oil (AWS46), and engine oil (HD40). Reusability of the kapok after application to various oils was also evaluated. Both loose (at its natural state) and densely packed kapok assemblies were examined. Sorption capacities of the packed kapok assemblies were very much dependent on their packing densities. At 0.02gcm(-3), its oil sorption capacities were 36, 43 and 45gg(-1) for diesel, ASW46 and HD40, respectively. The values decreased to 7.9, 8.1 and 8.6gg(-1) at 0.09gcm(-3). Its sorption capacities for the three oils were significantly higher than those of PP. When the oil-saturated kapok assemblies were allowed to drain, they exhibited high oil retention ability, with less than 8% of the absorbed diesel and HD40, and 12% of the absorbed AWS46 lost even after 1h of dripping. When applied on oil-over-water baths, the kapok exhibited high selectivity for the oils over the water; almost all oils spilled could be removed with the kapok, leaving an invisible oil slick on water. After the 4th cycle of reuse, the reused kapok assembly only lost 30% of its virgin sorption capacity if packed at 0.02gcm(-3), and the loss in sorption capacity was much less at higher packing densities. The hydrophobic-oleophilic characteristics of the kapok fiber could be attributed to its waxy surface, while its large lumen contributed to its excellent oil absorbency and retention capacity.

  13. Evaluation of ultrasound-assisted in situ sorbent formation solid-phase extraction method for determination of arsenic in water, food and biological samples.

    PubMed

    Ezoddin, Maryam; Majidi, Behrooz; Abdi, Khosrou

    2015-01-01

    A simple and rapid ultrasound-assisted in situ sorbent formation solid-phase extraction (UAISFSPE) coupled with electrothermal atomic absorption spectrometry detection (ET-AAS) was developed for preconcentration and determination of arsenic (As) in various samples. A small amount of cationic surfactant is dissolved in the aqueous sample containing As ions, which were complexed by ammonium pyrrolidinedithiocarbamate After shaking, a little volume of hexafluorophosphate (NaPF6) as an ion-pairing agent was added into the solution by a microsyringe. Due to the interaction between surfactant and ion-pairing agent, solid particles are formed. The alkyl groups of the surfactant in the solid particles strongly interact with the hydrophobic groups of analytes and become bound. Sonication aids the dispersion of the sorbent into the sample solution and mass transfer of the analyte into the sorbent, thus reducing the extraction time. The solid particles are centrifuged, and the sedimented particles can be dissolved in an appropriate solvent to recover the absorbed analyte. After separation, total arsenic (As(III) and As(V)) was determined by ET-AAS. Several experimental parameters were investigated and optimized. A detection limit of 7 ng L(-1) with preconcentration factor of 100 and relative standard deviation for 10 replicate determinations of 0.1 µg L(-1) As(III) were 4.5% achieved. Consequently, the method was applied to the determination of arsenic in certified reference materials, water, food and biological samples with satisfactory results.

  14. Factors affecting mercury control in utility flue gas using sorbent injection

    SciTech Connect

    Carey, T.R.; Hargrove, O.W. Jr.; Richardson, C.F.; Chang, R.; Meserole, F.B.

    1997-12-31

    Mercury continues to be considered for possible regulation in the electric power industry under Title 3 of the Clean Air Act Amendments of 1990. This possibility has generated interest in assessing whether cost-effective technologies exist for removing mercury from fossil-fired flue gas. One promising approach involves the direct injection of mercury sorbents, such as activated carbon, into the flue gas. Although this method has been effective at removing mercury in municipal waste incinerators, tests conducted to date on utility fossil-fired boilers show that mercury removal is much more difficult in utility flue gas. EPRI is conducting research to investigate mercury removal using sorbents. Bench-scale and pilot-scale tests have been conducted to determine the ability of different sorbents to remove mercury in simulated and actual flue gas streams. Bench-scale tests have investigated the effect of various sorbent and flue gas parameters on sorbent performance. These data are being used to develop a theoretical model for predicting mercury removal by sorbents at different conditions. The possibility of regenerating and recycling sorbents is also being evaluated. This paper describes the results of parametric bench-scale and pilot-scale tests investigating the removal of mercuric chloride and elemental mercury by activated carbon. Results obtained to date indicate that the adsorption capacity of a given sorbent is dependent on many factors, including the type of mercury being adsorbed, flue gas composition, and adsorption temperature. These data provide insight into potential mercury adsorption mechanisms and suggest that the removal of mercury involves both physical and chemical mechanisms. Understanding these effects is important since the performance of a given sorbent could vary significantly from site-to-site depending on coal- or gas-matrix composition.

  15. Kinetics of hot-gas desulfurization sorbents for transport reactors

    SciTech Connect

    K.C. Kwon

    2000-01-01

    Hot-gas desulfurization for the integrated gasification combined cycle (IGCC) process has been investigated by many researchers to remove effectively hydrogen sulfide with various metal oxide sorbents at elevated temperatures. Various metal oxide sorbents are formulated with metal oxides such as Fe, Co, Zn, and Ti. Initial reaction kinetics of formulated sorbents with hydrogen sulfide is studied in the presence of various amounts of moisture and hydrogen at various reaction temperatures. The objectives of this research are to study initial reaction kinetics for a sorbent-hydrogen sulfide heterogeneous reaction system, to investigate effects of concentrations of hydrogen sulfide, hydrogen, and moisture on dynamic absorption of H{sub 2}S into sorbents, to understand effects of space time of reaction gas mixtures on initial reaction kinetics of the sorbent-hydrogen sulfide system, and to evaluate effects of temperature and sorbent amounts on dynamic absorption of H{sub 2}S into sorbents. Experimental data on initial reaction kinetics of hydrogen sulfide with metal oxide sorbents were obtained with a 0.83-cm{sup 3} differential reactor. The reactivity of MCRH-67 sorbent and AHI-1 was examined. These sorbents were obtained from the Research Triangle Institute (RTI). The sorbents in the form of 70 {micro}m particles are reacted with 1,000--4,000 ppm hydrogen sulfide at 450--600 C. The range of space time of reaction gas mixtures is 0.03--0.09 s. The range of reaction duration is 4--14,400 s.

  16. Development of a Steel-Slag-Based, Iron-Functionalized Sorbent for an Autothermal Carbon Dioxide Capture Process.

    PubMed

    Tian, Sicong; Jiang, Jianguo; Hosseini, Davood; Kierzkowska, Agnieszka M; Imtiaz, Qasim; Broda, Marcin; Müller, Christoph R

    2015-11-01

    We propose a new class of autothermal CO2 -capture process that relies on the integration of chemical looping combustion (CLC) into calcium looping (CaL). In the new process, the heat released during the oxidation of a reduced metallic oxide is utilized to drive the endothermic calcination of CaCO3 (the regeneration step in CaL). Such a process is potentially very attractive (both economically and technically) as it can be applied to a variety of oxygen carriers and CaO is not in direct contact with coal (and the impurities associated with it) in the calciner (regeneration step). To demonstrate the practical feasibility of the process, we developed a low-cost, steel-slag-based, Fe-functionalized CO2 sorbent. Using this material, we confirm experimentally the feasibility to heat-integrate CaCO3 calcination with a Fe(II)/Fe(III) redox cycle (with regards to the heat of reaction and kinetics). The autothermal calcination of CaCO3 could be achieved for a material that contained a Ca/Fe ratio of 5:4. The uniform distribution of Ca and Fe in a solid matrix provides excellent heat transfer characteristics. The cyclic CO2 uptake and redox stability of the material is good, but there is room for further improvement.

  17. Development of a Steel-Slag-Based, Iron-Functionalized Sorbent for an Autothermal Carbon Dioxide Capture Process.

    PubMed

    Tian, Sicong; Jiang, Jianguo; Hosseini, Davood; Kierzkowska, Agnieszka M; Imtiaz, Qasim; Broda, Marcin; Müller, Christoph R

    2015-11-01

    We propose a new class of autothermal CO2 -capture process that relies on the integration of chemical looping combustion (CLC) into calcium looping (CaL). In the new process, the heat released during the oxidation of a reduced metallic oxide is utilized to drive the endothermic calcination of CaCO3 (the regeneration step in CaL). Such a process is potentially very attractive (both economically and technically) as it can be applied to a variety of oxygen carriers and CaO is not in direct contact with coal (and the impurities associated with it) in the calciner (regeneration step). To demonstrate the practical feasibility of the process, we developed a low-cost, steel-slag-based, Fe-functionalized CO2 sorbent. Using this material, we confirm experimentally the feasibility to heat-integrate CaCO3 calcination with a Fe(II)/Fe(III) redox cycle (with regards to the heat of reaction and kinetics). The autothermal calcination of CaCO3 could be achieved for a material that contained a Ca/Fe ratio of 5:4. The uniform distribution of Ca and Fe in a solid matrix provides excellent heat transfer characteristics. The cyclic CO2 uptake and redox stability of the material is good, but there is room for further improvement. PMID:26616682

  18. Comparison of uranium removal from groundwater by sorbents

    SciTech Connect

    Sams, B.; Blount, J.

    1997-12-31

    Several sorbents have been tested for the capability of uranium removal from two very chemically different groundwaters. Sorbents evaluated in the study include granular activated carbon, peat moss, ion exchange resin (all commercially available) as well as innovative products not commercially available. Screening experiments on all of the sorbents identified the most promising sorbents, which have been carried forward for isotherm and column studies. For the most promising sorbents, studies showed that uranium could be removed to below analytical detection limits. The effect of competing ions is also discussed.

  19. Development and validation of a method for air-quality and nuisance odors monitoring of volatile organic compounds using multi-sorbent adsorption and gas chromatography/mass spectrometry thermal desorption system.

    PubMed

    Ribes, Alejandra; Carrera, Guillem; Gallego, Eva; Roca, Xavier; Berenguer, M A José; Guardino, Xavier

    2007-01-26

    An analytical method based on thermal desorption (TD) coupled to gas chromatography (GC) and mass spectrometry detection (MS) has been developed and validated for the determination of a wide range of odor nuisance and air-quality volatile organic compounds (VOC) in air. New generation isocyanates, isocyanato- and isothiocyanatocyclohexane, have been included for the first time as target compounds due to their high occurrence in air samples. A dynamic air sampling method to trap gas and vapor on multi-sorbent tubes using portable pump equipment has been also developed. Sorbent tubes were filled with Carbotrap (70mg), Carbopack X (100mg) and Carboxen-569 (90mg). Validation of the TD-GC-MS method showed good selectivity, sensibility and precision according to Compendium Method TO-17 (US Environment Protection Agency) criteria. Limits of detection (signal-to-noise=3, ng in tube) ranges were 0.004-0.03ng (alcanes), 0.001-0.1ng (aromatics), 0.03-14ng (aldehydes), 0.003-7ng (alcohols), 0.003-0.04ng (chlorides), 0.02-0.5ng (esters), 0.002-0.1ng (ketones), 0.01-0.53ng (terpenes), 14-97ng (amides), 0.2-10ng (isocyanates) and 0.001ng (carbon disulfide). The linear dynamic range was over 3-5 orders of magnitude, depending of the VOC. TD-GC-MS analysis was reproducible, with relative standard deviation (n=5) within 20%. VOCs breakthrough examination showed no significant losses when about 2000ng standard was prepared. In order to evaluate the performance of the developed method on real samples, several industrial and urban air samples were analysed. VOCs were found to be stable on the sorbent tubes for at least 1 week when stored at 4 degrees C.

  20. Deep Bed Iodine Sorbent Testing FY 2011 Report

    SciTech Connect

    Nick Soelberg; Tony Watson

    2011-08-01

    Nuclear fission results in the production of fission products (FPs) and activation products that increasingly interfere with the fission process as their concentrations increase. Some of these fission and activation products tend to evolve in gaseous species during used nuclear fuel reprocessing. Analyses have shown that I129, due to its radioactivity, high potential mobility in the environment, and high longevity (half life of 15.7 million years), can require control efficiencies of up to 1,000x or higher to meet regulatory emission limits. Deep-bed iodine sorption testing has been done to evaluate the performance of solid sorbents for capturing iodine in off-gas streams from nuclear fuel reprocessing plants. The objectives of the FY 2011 deep bed iodine sorbent testing are: (1) Evaluate sorbents for iodine capture under various conditions of gas compositions and operating temperature (determine sorption efficiencies, capacities, and mass transfer zone depths); and (2) Generate data for dynamic iodine sorption modeling. Three tests performed this fiscal year on silver zeolite light phase (AgZ-LP) sorbent are reported here. Additional tests are still in progress and can be reported in a revision of this report or a future report. Testing was somewhat delayed and limited this year due to initial activities to address some questions of prior testing, and due to a period of maintenance for the on-line GC. Each test consisted of (a) flowing a synthetic blend of gases designed to be similar to an aqueous dissolver off-gas stream over the sorbent contained in three separate bed segments in series, (b) measuring each bed inlet and outlet gas concentrations of iodine and methyl iodide (the two surrogates of iodine gas species considered most representative of iodine species expected in dissolver off-gas), (c) operating for a long enough time to achieve breakthrough of the iodine species from at least one (preferably the first two) bed segments, and (d) post-test purging

  1. Evaluating Instructional Development Programmes.

    ERIC Educational Resources Information Center

    Knapper, Christopher K.

    The effectiveness of instructional development evaluation programs is assessed. It is suggested that although it is a basic tenet in instructional development that teaching improvement is closely linked to effective evaluation, it is ironical that most instructional development programs have themselves been evaluated only superficially, if at all.…

  2. Regenerable solid imine sorbents

    DOEpatents

    Gray, McMahan; Champagne, Kenneth J.; Fauth, Daniel; Beckman, Eric

    2013-09-10

    Two new classes of amine-based sorbents are disclosed. The first class comprises new polymer-immobilized tertiary amine sorbents; the second class new polymer-bound amine sorbents. Both classes are tailored to facilitate removal of acid anhydrides, especially carbon dioxide (CO.sub.2), from effluent gases. The amines adsorb acid anhydrides in a 1:1 molar ratio. Both classes of amine sorbents adsorb in the temperature range from about 20.degree. C. upwards to 90.degree. C. and can be regenerated by heating upwards to 100.degree. C.

  3. Elemental sulfur recovery from desulfurization sorbents in advanced power systems

    SciTech Connect

    Dorchak, T.P.; Gangwal, S.K.; Turk, B.S.

    1995-12-31

    Regenerable metal oxide sorbents, such as zinc titanate, are being developed to efficiently remove hydrogen sulfide (H{sub 2}S) from coal gas in advanced power systems. Dilute air regeneration of the sorbents produces a tailgas containing a few percent sulfur dioxide (SO{sub 2}). Catalytic reduction of the SO{sub 2} to elemental sulfur with a coal gas slipstream using the Direct Sulfur Recovery Process (DSRP) is a leading first-generation technology. Currently the DSRP is undergoing field testing at gasifier sites. The objective of this study is to develop second-generation processes that produce elemental sulfur with limited use of coal gas. Novel approaches that were evaluated to produce elemental sulfur from sulfided sorbents include (1) SO{sub 2} regeneration, (2) substoichiometric oxidation, (3) steam regeneration followed by H{sub 2}S oxidation, and (4) steam-air regeneration. Experimental results at high temperature and high pressure demonstrate that, with simple sorbent modifications, direct regeneration to elemental sulfur is feasible without the use of coal gas.

  4. Engineered sorbent barriers for improved low-level waste disposal

    SciTech Connect

    Mitchell, S.J.; Freeman, H.D.

    1987-01-01

    The Engineered Sorbent Barriers Program at Pacific Northwest Lab., supported by the US Dept. of Energy's Low-Level Waste (LLW) Management Program, is developing sorbent materials to prevent the migration of radionuclides from LLW sites. Unlike impermeable barriers, sorbent barriers allow moisture to pass while selectively sorbing contaminants. This would prevent filling the waste site with water at humid sites, referred to as the bathtub effect. The sorptive behavior of these barriers is similar to the ion-exchange properties that many soils possess for certain radionuclides. However, the degree of sorption of radionuclides is dependent on the type of soil, the specific radionuclide, and the presence of competing ions and organic complexants. Therefore, the use of sorptive additives as radionuclide barriers is recommended to prevent radionuclide migration from the waste site. The experimental work discussed in this paper was directed toward identifying and evaluating sorbent materials for three radionuclides of major concern in defense LLW: /sup 137/Cs, /sup 60/Co, and /sup 90/Sr. No single material was found to be effective for sorbing all three radionuclides of interest. Therefore, formulations were developed containing A-51 zeolite or clinoptilolite for sorbing strontium, greensand or red pottery clay for sorbing cesium, and activated charcoal for sorbing cobalt.

  5. Technical and economic evaluation of dry sorbent injection for SO/sub 2/ control using sodium compounds

    SciTech Connect

    Green, G.P.; Carr, R.C.; Hooper, R.G.

    1984-01-01

    Public Service Company of Colorado (PSCC) has committed to all-dry sorbent injection for SO/sub 2/ control on a new 500 MW coal-fired boiler, Pawnee Unit 2. Although no commitment has been made for construction of Pawnee 2, for engineering and planning purposes it is scheduled to begin service in 1990 burning western, low-sulfur, subbituminous coal. PSCC is currently the only electric utility to announce firm plans to employ this control technology. The purpose of this paper is to present the reasons for this commitment. It is hoped that this discussion will be of benefit to other electric utilities considering SO/sub 2/ control options.

  6. Development of an enzyme-linked immuno-sorbent assay (ELISA) method for carbofuran residues.

    PubMed

    Yang, Jinyi; Wang, Hong; Jiang, Yueming; Sun, Yuanming; Pan, Ke; Lei, Hongtao; Wu, Qing; Shen, Yudong; Xiao, Zhili; Xu, Zhenlin

    2008-04-17

    The haptens 4-[[(2,3-dihydro-2,2-dimethyl-7-benzofuranyloxy)carbonyl]-amino]butanoic acid (BFNB) and 6-[((2,3-dihydro-2,2-dimethyl-7-benzofuranyloxy)-carbonylamino]hexanoic acid (BFNH) were synthesized and then used to develop a rapid,specific and sensitive ELISA method to determine residues of the pesticide carbofuran in a variety of matrices. A hybridoma cell line (5D3) producing anti-carbofuran monoclonal antibodies (MAbs) was also established. Based on the MAbs in combination with the heterologous hapten BFNH coupled to either horseradish peroxidase (HRP) or ovalbumin(OVA), four ELISAs (formats I-IV) for the quantification of carbofuran were developed and compared. Among them, the optimized format II (the conjugate-coated direct competitive ELISA) showed the best characteristics, with an IC50 value of 18.49 ng/mL, a limit of detection of 0.11 ng/mL and the shortest assay time (1 h). This ELISA method was then applied to the determinations of carbofuran in environmental water, soil and food samples. The relative standard deviations (R.S.D.s) ranged from 1.8% to 21.3% and the mean recoveries were 104.6%, 108.3%, 106.3% and 100.1% for water, soil, lettuce and cabbage, respectively. Thus, the ELISA method of format II exhibited the potential to develop commercial ELISA kits for a rapid detection of carbofuran for human health and environmental safety.

  7. Evaluation of the stability of a mixture of volatile organic compounds on sorbents for the determination of emissions from indoor materials and products using thermal desorption/gas chromatography/mass spectrometry.

    PubMed

    Brown, Veronica M; Crump, Derrick R; Plant, Neil T; Pengelly, Ian

    2014-07-11

    The standard method for the determination of volatile organic compounds (VOCs) in indoor and test chamber air (ISO 16000-6:2011) specifies sampling onto the sorbent Tenax TA followed by analysis using thermal desorption/gas chromatography/mass spectrometry (TD/GC/MS). The informative Annex D to the standard suggests the use of multi-sorbent samplers to extend the volatility range of compounds which can be determined. The aim of this study was to investigate the storage performance of Tenax TA and two multi-sorbent tubes loaded with a mixture of nine VOCs of relevance for material emissions testing. The sorbent combinations tested were quartz wool/Tenax TA/Carbograph™ 5TD and quartz wool/Tenax TA/Carbopack™ X. A range of loading levels, loading conditions (humidities and air volume), storage times (1-4 weeks) and storage conditions (refrigerated and ambient) were investigated. Longer term storage trials (up to 1 year) were conducted with Tenax TA tubes to evaluate the stability of tubes used for proficiency testing (PT) of material emissions analyses. The storage performance of the multi-sorbent tubes tested was found to be equal to that for Tenax TA, with recoveries after 4 weeks storage of within about 10% of the amounts loaded. No consistent differences in recoveries were found for the different loading or storage conditions. The longer term storage trials also showed good recovery for these compounds, although two other compounds, hexanal and BHT, were found to be unstable when stored on Tenax TA. The results of this study provide confidence in the stability of nine analytes for up to 4 weeks on two multi-sorbent tubes for material emissions testing and the same compounds loaded on Tenax TA sorbent for a recently introduced PT scheme for material emissions testing.

  8. Development and testing of inorganic sorbents for radionuclide and heavy metal separations

    SciTech Connect

    Collins, J.

    1996-10-01

    The objectives of this task are to develop, prepare, and test microspheres and granular forms of inorganic ion exchangers to remove radionuclides and heavy metals from waste streams occurring at various sites. Several inorganic materials, such as hexacyanoferrates, titanates, phosphates, and oxides have high selectivities and efficiencies for separating and removing radionuclides such as uranium, technetium, cesium and strontium, and metals such as cobalt, silver, zinc, and zirconium from aqueous waste streams. However, these sorvents frequently exist only as powders and consequently are not readily adaptable to continuous processing such as column chromatography.

  9. Testing of zinc titanate desulfurization sorbents for moving-bed applications

    SciTech Connect

    Ayala, R.E.; Gal, E.; Gupta, R.P.

    1993-09-01

    Sorbents developed for moving-bed systems must comply with a minimum of chemical and mechanical durability performance characteristics in order to be considered acceptable for long-term operation. Among the desired properties, a sorbent must have: (1) High chemical reactivity, as measured by the rate of sulfur absorption and the total sulfur loading on the sorbent. (2) High mechanical strength, as measured by the pellet crush strength and the attrition resistance; (3) Suitable pellet morphology, as given by pellet size and shape to promote good bulk flow ability and seasonable porosity to increase reactivity. Formulation 2A1.7M (UCI designation L-3787M) was selected by DOE as the baseline formulation for performance evaluation of Option 3 sorbents. This baseline formulation is a rounded zinc titanate sorbent containing a 2:1 Zn:Ti molar ratio, 1.7% molybdenum (equivalent to 2.5% MoO{sub 3}), and 3% bentonite binder that had been previously tested under the Option 2 program. Zinc titanate sorbents were prepared by UCI as rounded spherical or ellipsoidal pellets. The fabrication procedure is targeted at achieving a balance of mechanical strength (crush strength and attrition resistance) and chemical reactivity by controlling the pellet internal porosity.

  10. Assessing sorbent injection mercury control effectiveness in flue gas streams

    USGS Publications Warehouse

    Carey, T.R.; Richardson, C.F.; Chang, R.; Meserole, F.B.; Rostam-Abadi, M.; Chen, S.

    2000-01-01

    One promising approach for removing mercury from coal-fired, utility flue gas involves the direct injection of mercury sorbents. Although this method has been effective at removing mercury in municipal waste incinerators, tests conducted to date on utility coal-fired boilers show that mercury removal is much more difficult in utility flue gas. EPRI is conducting research to investigate mercury removal using sorbents in this application. Bench-scale, pilot-scale, and field tests have been conducted to determine the ability of different sorbents to remove mercury in simulated and actual flue gas streams. This paper focuses on recent bench-scale and field test results evaluating the adsorption characteristics of activated carbon and fly ash and the use of these results to develop a predictive mercury removal model. Field tests with activated carbon show that adsorption characteristics measured in the lab agree reasonably well with characteristics measured in the field. However, more laboratory and field data will be needed to identify other gas phase components which may impact performance. This will allow laboratory tests to better simulate field conditions and provide improved estimates of sorbent performance for specific sites. In addition to activated carbon results, bench-scale and modeling results using fly ash are presented which suggest that certain fly ashes are capable of adsorbing mercury.

  11. Advanced in-duct sorbent injection for SO{sub 2} control. Topical report No. 4, Task 3, Optimized advanced process evaluation

    SciTech Connect

    Rosenhoover, W.A.; Stouffer, M.R.; Maskew, J.T.; Withum, J.A.; Wu, M.M.; Winschel, R.A.

    1994-12-01

    The objective of this research project is to develop second- generation duct injection technology as a cost-effective compliance option for the 1990 Clean Air Act Amendments. Specific performance targets are 90% SO{sup 2} removal and 60% sorbent utilization efficiency. Research focused on the Advanced Coolside process, which showed the potential for exceeding these targets. The objective of Subtask 3.1, Performance Testing, was to develop process performance and operability data for design and scale-up of the optimized Advance Coolside process. Results of long-term pilot plant testing with 24 hour/day operation provided a positive indication of process operability. The objective of Subtask 3.2, Waste Characterization, was to determine the chemical and physical properties of the waste materials for designing the waste handling and disposal systems for the process. Test results show that the combined spent sorbent and fly ash waste is suitable for landfilling. Further, the waste management study indicated a potential for by-product utilization for synthetic aggregate production; a more thorough investigation of this potential is required.

  12. Adsorption and Ultrasound-Assisted Sorbent Regeneration

    SciTech Connect

    Yuhe Wang; Liping Ma; Ralph T. Yang

    2006-09-30

    This work was conducted for the department of Energy. In this work, we developed a class of new sorbents that were highly sulfur selective and had high sulfur capacities. The study consisted of two sections. Development of the new sorbents is described in Section 1, and Section was a fundamental study, conducted for a better understanding for desulfurization of jet fuels. More details of the results are given blow separately for the two sections.

  13. Desulfurization sorbent regeneration

    DOEpatents

    Jalan, V.M.; Frost, D.G.

    1982-07-07

    A spent solid sorbent resulting from the removal of hydrogen sulfide from a fuel gas flow is regenerated with a steam-air mixture. The mixture of steam and air may also include additional nitrogen or carbon dioxide. The gas mixture contacts the spent sorbent containing metal sulfide at a temperature above 500/sup 0/C to regenerate the sulfide to metal oxide or carbonate. Various metal species including the period four transition metals and the lanthanides are suitable sorbents that may be regenerated by this method. In addition, the introduction of carbon dioxide gas permits carbonates such as those of strontium, barium and calcium to be regenerated. The steam permits regeneration of spent sorbent without formation of metal sulfate. Moreover, the regeneration will proceed with low oxygen concentrations and will occur without the increase in temperature to minimize the risk of sintering and densification of the sorbent. This method may be used for high-temperature fuel cells.

  14. Development of cost-effective noncarbon sorbents for Hg(0) removal from coal-fired power plants.

    PubMed

    Lee, Joo-Youp; Ju, Yuhong; Keener, Tim C; Varma, Rajender S

    2006-04-15

    Noncarbonaceous materials or mineral oxides (silica gel, alumina, molecular sieves, zeolites, and montmorillonite) were modified with various functional groups such as amine, amide, thiol, urea, and active additives such as elemental sulfur, sodium sulfide, and sodium polysulfide to examine their potential as sorbents for the removal of elemental mercury (Hg(0)) vapor at coal-fired utility power plants. A number of sorbent candidates such as amine- silica gel, urea- silica gel, thiol- silica gel, amide-silica gel, sulfur-alumina, sulfur-molecular sieve, sulfur-montmorillonite, sodium sulfide-montmorillonite, and sodium polysulfide-montmorillonite, were synthesized and tested in a lab-scale fixed-bed system under an argon flow for screening purposes at 70 degrees C and/or 140 degrees C. Several functionalized silica materials reported in previous studies to effectively control heavy metals in the aqueous phase showed insignificant adsorption capacities for Hg(0) control in the gas phase, suggesting that mercury removal mechanisms in both phases are different. Among elemental sulfur-, sodium sulfide-, and sodium polysulfide-impregnated inorganic samples, sodium polysulfide-impregnated montmorillonite K 10 showed a moderate adsorption capacity at 70 degrees C, which can be used for sorbent injection prior to the wet FGD system.

  15. Replacement of charcoal sorbent in the VOST

    SciTech Connect

    Johnson, L.D.; Fuerst, R.G.; Foster, A.L.; Bursey, J.T.

    1993-01-01

    EPA Method 0030, the Volatile Organic Sampling Train (VOST), for sampling volatile organics from stationary sources, specifies the use of petroleum-base charcoal in the second sorbent tube. Charcoal has proven to be a marginal performer as a sampling sorbent, partly due to inconsistency in analyte recovery. In addition, commercial availability of petroleum charcoal for VOST tubes has been variable. Lack of data on comparability and variability of charcoals for VOST application has created uncertainty when other charcoals are substituted. Five potential sorbent replacements for charcoal in Method 0030 were evaluated along with a reference charcoal. Two of the sorbents tested, Ambersorb XE-340 and Tenax GR, did not perform well enough to qualify as replacements. Three candidates, Anasorb 747, Carbosieve S-III and Kureha Beaded Activated Charcoal, performed adequately, and produced statistically equivalent results. Anasorb 747 appears to be an acceptable replacement for petroleum charcoal, based on a combination of performance, availability, and cost.

  16. Evaluation of graphene-based sorbent in the determination of polar environmental contaminants in water by micro-solid phase extraction-high performance liquid chromatography.

    PubMed

    Naing, Nyi Nyi; Li, Sam Fong Yau; Lee, Hian Kee

    2016-01-01

    A facile method of extraction using porous membrane protected micro-solid phase extraction (μ-SPE) with a graphene-based sorbent followed by high performance liquid chromatography-ultraviolet detector was developed. The reduced graphene oxide (r-GO) (1mg), synthesized from graphite oxide, was enclosed in a polypropylene bag representing the μ-SPE device, which was used for the extraction of estrogens such as estrone, 17β-estradiol, 17α-ethynylestradiol and diethylstilbestrol in water. The r-GO obtained was identified and characterized by Fourier transform infrared, transmission electron microscopy, scanning electron microscopy and thermogravimetric analysis. The sorbent was loaded with sodium dodecyl sulfate by sonication to prevent agglomeration in aqueous solution. With this method, low limits of detection of between 0.24 and 0.52 ng L(-1) were achieved. For estrogen analysis a linear calibration range of 0.01-100 μg L(-1) was obtained, with the coefficients of determination (r(2)) higher than 0.992. This proposed method was successfully applied to determine estrogens in water. PMID:26709072

  17. Development and Test Evaluations for Ni-DOBDC Metal Organic Framework (MOF) Engineered Forms

    SciTech Connect

    Troy G. Garn; Mitchell Greenhalgh

    2013-07-01

    A joint effort to prepare engineered forms of a Ni-DOBDC metal organic framework (MOF) was completed with contributions from PNNL, SNL and the INL. Two independent methods were used at INL and SNL to prepare engineered form (EF) sorbents from Ni-DOBDC MOF powder developed and prepared at PNNL. Xe and Kr capacity test evaluations were performed at ambient temperature with the cryostat experimental setup at INL. The initial INL EF MOF test results indicated a Xe capacity of 1.6 mmol/kg sorbent and no Kr capacity. A large loss of surface area also occurred during minimal testing rendering the INL EF MOF unusable. Four capacity tests were completed using the SNL EF MOF at ambient temperature and resulted in Xe capacities of 1.4, 4.2, 5.0 and 3.8 mmol/kg sorbent with no Kr capacity observed in any ambient temperature tests. Two additional capacity tests were performed at 240 K to further evaluate SNL EF MOF performance. Xe capacities of 50.7 and 49.3 mmol/kg of sorbent and Kr capacities of 0.77 and 0.69 mmol/kg of sorbent were obtained, respectively. Following the adsorption evaluations, the SNL EF MOF material had lost about 40 % of the initial mass and 40 % of the initial surface area. In general, the Xe capacity results at ambient temperature for the INL and SNL EF Ni-DOBDC MOF’s were lower than 9.8 mmol Xe/kg sorbent test results reported by INL in FY-12 using PNNL’s inital EF supplied material.

  18. Evaluation of various additives on the preparation of rice husk ash (RHA)/CaO-based sorbent for flue gas desulfurization (FGD) at low temperature.

    PubMed

    Dahlan, Irvan; Lee, Keat Teong; Kamaruddin, Azlina Harun; Mohamed, Abdul Rahman

    2009-01-15

    This paper examines the effectiveness of 10 additives toward improving SO2 sorption capacities (SSC) of rice husk ash (RHA)/lime (CaO) sorbent. The additives examined are NaOH, CaCl2, LiCl, NaHCO3, NaBr, BaCl2, KOH, K2HPO4, FeCl3 and MgCl2. Most of the additives tested increased the SSC of RHA/CaO sorbent, whereby NaOH gave highest SSC (30mg SO2/g sorbent) at optimum concentration (0.25mol/l) compared to other additives examined. The SSC of RHA/CaO sorbent prepared with NaOH addition was also increases from 17.2 to 39.5mg SO2/g sorbent as the water vapor increases from 0% RH to 80% RH. This is probably due to the fact that most of additives tested act as deliquescent material, and its existence increases the amount of water collected on the surface of the sorbent, which played an important role in the reaction between the dry-type sorbent and SO2. Although most of the additives were shown to have positive effect on the SSC of the RHA/CaO sorbent, some were found to have negative or insignificant effect. Thus, this study demonstrates that proper selection of additives can improve the SSC of RHA/CaO sorbent significantly. PMID:18462871

  19. Strengthening Evaluation for Development

    ERIC Educational Resources Information Center

    Ofir, Zenda

    2013-01-01

    Although some argue that distinctions between "evaluation" and "development evaluation" are increasingly superfluous, it is important to recognize that some distinctions still matter. The severe vulnerabilities and power asymmetries inherent in most developing country systems and societies make the task of evaluation…

  20. A FLUID SORBENT RECYCLING DEVICE FOR INDUSTRIAL FLUID USERS

    EPA Science Inventory

    A roller compression Extractor® that extracts fluids from reusable sorbent pads was evaluated as a method of waste reduction. The extraction device, evaluated for industrial fluid users in New Jersey, was found to be effective in recycling unpleated sorbent pads, especially ...

  1. Long Duration Sorbent Testbed

    NASA Technical Reports Server (NTRS)

    Howard, David F.; Knox, James C.; Long, David A.; Miller, Lee; Cmaric, Gregory; Thomas, John

    2016-01-01

    The Long Duration Sorbent Testbed (LDST) is a flight experiment demonstration designed to expose current and future candidate carbon dioxide removal system sorbents to an actual crewed space cabin environment to assess and compare sorption working capacity degradation resulting from long term operation. An analysis of sorbent materials returned to Earth after approximately one year of operation in the International Space Station's (ISS) Carbon Dioxide Removal Assembly (CDRA) indicated as much as a 70% loss of working capacity of the silica gel desiccant material at the extreme system inlet location, with a gradient of capacity loss down the bed. The primary science objective is to assess the degradation of potential sorbents for exploration class missions and ISS upgrades when operated in a true crewed space cabin environment. A secondary objective is to compare degradation of flight test to a ground test unit with contaminant dosing to determine applicability of ground testing.

  2. Mercury removal sorbents

    DOEpatents

    Alptekin, Gokhan

    2016-03-29

    Sorbents and methods of using them for removing mercury from flue gases over a wide range of temperatures are disclosed. Sorbent materials of this invention comprise oxy- or hydroxyl-halogen (chlorides and bromides) of manganese, copper and calcium as the active phase for Hg.sup.0 oxidation, and are dispersed on a high surface porous supports. In addition to the powder activated carbons (PACs), this support material can be comprised of commercial ceramic supports such as silica (SiO.sub.2), alumina (Al.sub.2O.sub.3), zeolites and clays. The support material may also comprise of oxides of various metals such as iron, manganese, and calcium. The non-carbon sorbents of the invention can be easily injected into the flue gas and recovered in the Particulate Control Device (PCD) along with the fly ash without altering the properties of the by-product fly ash enabling its use as a cement additive. Sorbent materials of this invention effectively remove both elemental and oxidized forms of mercury from flue gases and can be used at elevated temperatures. The sorbent combines an oxidation catalyst and a sorbent in the same particle to both oxidize the mercury and then immobilize it.

  3. Evaluation of intercalated α-zirconium phosphate as sorbent in separation and detection of sulfonamides in honey.

    PubMed

    Hou, Juan; Yan, Jin; Zhang, Fengshuang; Zhao, Qi; Chen, Haiyan; Zhang, Yiqun; Li, Guijie; Li, Yi; Ding, Lan

    2014-05-01

    This paper presented a simple and effective solid-phase extraction method using α-zirconium phosphate intercalated by hexadecyl trimethyl ammonium bromide (α-ZrP-CTMAB) as a novel adsorbent. Surfactant-assisted method was applied to prepare α-ZrP-CTMAB whose sorbent properties and extraction efficiency were investigated. Four sulfonamides (SAs) in honey were selected as analytical models and finally determined by liquid chromatography-tandem mass spectrometry. The recoveries of SAs at three spiked levels (10, 100, 1000ngg(-1)) were in the range of 58.7-99.3% and the relative standard deviations ranged from 2.69% to 7.48%. The detection limits obtained were 0.25-0.5ngg(-1). Compared with other methods in the literatures, the proposed method reduced the consumption of organic solvents and simplified the sample preparation procedure for the analysis of SAs in honey. Therefore, modified α-ZrP showed great potential in the analysis of pollutants in complex samples.

  4. Hot coal gas desulfurization with manganese-based sorbents. Final report, September 1992--December 1994

    SciTech Connect

    Hepworth, M.T.; Slimane, R.B.

    1994-11-01

    The focus of much current work being performed by the Morgantown Energy Technology Center (METC) of the Department of Energy on hot coal-derived fuel gas desulfurization is in the use of zinc-based sorbents. METC has shown interest in formulating and testing manganese-based pellets as alternative effective sulfur sorbents in the 700 to 1200{degree}C temperature range. To substantiate the potential superiority of Mn-based pellets, a systematic approach toward the evaluation of the desulfurizing power of single-metal sorbents is developed based on thermodynamic considerations. This novel procedure considered several metal-based sorbents and singled out manganese oxide as a prime candidate sorbent capable of being utilized under a wide temperature range, irrespective of the reducing power (determined by CO{sub 2}/CO ratio) of the fuel gas. Then, the thermodynamic feasibility of using Mn-based pellets for the removal of H{sub 2}S from hot-coal derived fuel gases, and the subsequent oxidative regeneration of loaded (sulfided) pellets was established. It was concluded that MnO is the stable form of manganese for virtually all commercially available coal-derived fuel gases. In addition, the objective of reducing the H{sub 2}S concentration below 150 ppMv to satisfy the integrated gasification combined cycle system requirement was shown to be thermodynamically feasible. A novel process is developed for the manufacture of Mn-based spherical pellets which have the desired physical and chemical characteristics required.

  5. Advanced low-temperature sorbents

    SciTech Connect

    Ayala, R.E.; Venkataramani, V.S.; Abbasian, J.; Hill, A.H.

    1995-12-01

    A number of promising technologies are currently being optimized for coal-based power generation, including the Integrated-Gasification Combined Cycle (IGCC) system. If IGCC is to be used successfully for power generation, an economic and efficient way must be found to remove the contaminants, particularly sulfur species, found in coal gas. Except for the hot gas desulfurization system, all major components of IGCC are commercially available or have been shown to meet system requirements. Over the last two decades, the U.S. Department of Energy/Morgantown Energy Technology Center (DOE/METC) has sponsored development of various configurations of high-temperature desulfurization systems including fixed-bed, moving-bed, transport-bed, and fluidized-bed systems. Because of their mode of operation and requirements for sorbent manufacturing, the fixed-bed systems can generally use the same materials as moving-bed configurations, i.e., pelletized or extruded sorbents, while fluidized-bed (circulating or bubbling configurations) and transport reactor configurations use materials generally described as agglomerated or granulated.The objective of this program is to remove hydrogen sulfides from coal gas using sorbent materials.

  6. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect

    Jha, M.C.; Baltich, L.K.

    1987-02-23

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  7. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect

    Jha, M.C.; Berggren, M.H.

    1989-05-02

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  8. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect

    Jha, M.C.; Baltich, L.K.; Berggren, M.H.

    1987-05-18

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  9. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect

    Silaban, A.; Harrison, D.P. . Dept. of Chemical Engineering)

    1989-05-02

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  10. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect

    Jha, M.C.; Berggren, M.H.

    1988-11-14

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  11. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect

    Jha, M.C.; Baltich, L.K.; Berggren, M.H.

    1987-08-28

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  12. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect

    Jha, M.C.; Berggren, M.H.

    1988-08-19

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  13. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect

    Jha, M.C.; Berggren, M.H.

    1989-03-06

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  14. Development of Nano-Sulfide Sorbent for Efficient Removal of Elemental Mercury from Coal Combustion Fuel Gas.

    PubMed

    Li, Hailong; Zhu, Lei; Wang, Jun; Li, Liqing; Shih, Kaimin

    2016-09-01

    The surface area of zinc sulfide (ZnS) was successfully enlarged using nanostructure particles synthesized by a liquid-phase precipitation method. The ZnS with the highest surface area (named Nano-ZnS) of 196.1 m(2)·g(-1) was then used to remove gas-phase elemental mercury (Hg(0)) from simulated coal combustion fuel gas at relatively high temperatures (140 to 260 °C). The Nano-ZnS exhibited far greater Hg(0) adsorption capacity than the conventional bulk ZnS sorbent due to the abundance of surface sulfur sites, which have a high binding affinity for Hg(0). Hg(0) was first physically adsorbed on the sorbent surface and then reacted with the adjacent surface sulfur to form the most stable mercury compound, HgS, which was confirmed by X-ray photoelectron spectroscopy analysis and a temperature-programmed desorption test. At the optimal temperature of 180 °C, the equilibrium Hg(0) adsorption capacity of the Nano-ZnS (inlet Hg(0) concentration of 65.0 μg·m(-3)) was greater than 497.84 μg·g(-1). Compared with several commercial activated carbons used exclusively for gas-phase mercury removal, the Nano-ZnS was superior in both Hg(0) adsorption capacity and adsorption rate. With this excellent Hg(0) removal performance, noncarbon Nano-ZnS may prove to be an advantageous alternative to activated carbon for Hg(0) removal in power plants equipped with particulate matter control devices, while also offering a means of reusing fly ash as a valuable resource, for example as a concrete additive. PMID:27508312

  15. Development of Nano-Sulfide Sorbent for Efficient Removal of Elemental Mercury from Coal Combustion Fuel Gas.

    PubMed

    Li, Hailong; Zhu, Lei; Wang, Jun; Li, Liqing; Shih, Kaimin

    2016-09-01

    The surface area of zinc sulfide (ZnS) was successfully enlarged using nanostructure particles synthesized by a liquid-phase precipitation method. The ZnS with the highest surface area (named Nano-ZnS) of 196.1 m(2)·g(-1) was then used to remove gas-phase elemental mercury (Hg(0)) from simulated coal combustion fuel gas at relatively high temperatures (140 to 260 °C). The Nano-ZnS exhibited far greater Hg(0) adsorption capacity than the conventional bulk ZnS sorbent due to the abundance of surface sulfur sites, which have a high binding affinity for Hg(0). Hg(0) was first physically adsorbed on the sorbent surface and then reacted with the adjacent surface sulfur to form the most stable mercury compound, HgS, which was confirmed by X-ray photoelectron spectroscopy analysis and a temperature-programmed desorption test. At the optimal temperature of 180 °C, the equilibrium Hg(0) adsorption capacity of the Nano-ZnS (inlet Hg(0) concentration of 65.0 μg·m(-3)) was greater than 497.84 μg·g(-1). Compared with several commercial activated carbons used exclusively for gas-phase mercury removal, the Nano-ZnS was superior in both Hg(0) adsorption capacity and adsorption rate. With this excellent Hg(0) removal performance, noncarbon Nano-ZnS may prove to be an advantageous alternative to activated carbon for Hg(0) removal in power plants equipped with particulate matter control devices, while also offering a means of reusing fly ash as a valuable resource, for example as a concrete additive.

  16. Measurement of Mercury in Flue Gas Based on an Aluminum Matrix Sorbent

    PubMed Central

    Wang, Juan; Xu, Wei; Wang, Xiaohao; Wang, Wenhua

    2011-01-01

    The measurement of total mercury in flue gas based on an economical aluminum matrix sorbent was developed in this paper. A sorbent trap consisted of three tubes was employed to capture Hg from flue gas. Hg trapped on sorbent was transferred into solution by acid leaching and then detected by CVAAS. Hg adsorbed on sorbent was recovered completely by leaching process. The 87.7% recovery of Hg in flue gas by tube 1 and tube 2 was obtained on the equipment of coal combustion and sampling in lab. In order to evaluate the ability to recover and accurately quantify Hg0 on the sorbent media, the analytical bias test on tube 3 spiked with Hg0 was also performed and got the average recovery of 97.1%. Mercury measurements based on this method were conducted for three coal-fired power plants in China. The mercury in coal is distributed into bottom ash, electrostatic precipitator (ESP) ash, wet flue gas desulfurization (WFGD) reactant, and flue gas, and the relative distribution varied depending on factors such as the coal type and the operation conditions of plants. The mercury mass balances of three plants were also calculated which were 91.6%, 77.1%, and 118%, respectively. The reliability of this method was verified by the Ontario Hydro (OH) method either in lab or in field. PMID:22235178

  17. Measurement of mercury in flue gas based on an aluminum matrix sorbent.

    PubMed

    Wang, Juan; Xu, Wei; Wang, Xiaohao; Wang, Wenhua

    2011-01-01

    The measurement of total mercury in flue gas based on an economical aluminum matrix sorbent was developed in this paper. A sorbent trap consisted of three tubes was employed to capture Hg from flue gas. Hg trapped on sorbent was transferred into solution by acid leaching and then detected by CVAAS. Hg adsorbed on sorbent was recovered completely by leaching process. The 87.7% recovery of Hg in flue gas by tube 1 and tube 2 was obtained on the equipment of coal combustion and sampling in lab. In order to evaluate the ability to recover and accurately quantify Hg(0) on the sorbent media, the analytical bias test on tube 3 spiked with Hg(0) was also performed and got the average recovery of 97.1%. Mercury measurements based on this method were conducted for three coal-fired power plants in China. The mercury in coal is distributed into bottom ash, electrostatic precipitator (ESP) ash, wet flue gas desulfurization (WFGD) reactant, and flue gas, and the relative distribution varied depending on factors such as the coal type and the operation conditions of plants. The mercury mass balances of three plants were also calculated which were 91.6%, 77.1%, and 118%, respectively. The reliability of this method was verified by the Ontario Hydro (OH) method either in lab or in field. PMID:22235178

  18. Low temperature SO{sub 2} removal with solid sorbents in a circulating fluidized bed absorber. Final report

    SciTech Connect

    Lee, S.K.; Keener, T.C.

    1994-10-10

    A novel flue gas desulfurization technology has been developed at the University of Cincinnati incorporating a circulating fluidized bed absorber (CFBA) reactor with dry sorbent. The main features of CFBA are high sorbent/gas mixing ratios, excellent heat and mass transfer characteristics, and the ability to recycle partially utilized sorbent. Subsequently, higher SO{sub 2} removal efficiencies with higher overall sorbent utilization can be realized compared with other dry sorbent injection scrubber systems.

  19. Staff Development and Evaluation.

    ERIC Educational Resources Information Center

    Dempsey, Richard A.; Breyer, Norman L.

    An ongoing behavioral model for implementing staff development and evaluation procedures is proposed, which systematically focuses on assessing and facilitating behavioral change in the classroom and enables the educational executive to assess what is actually happening there. The administrator is thus provided with the necessary information to…

  20. Long Duration Sorbent Testbed

    NASA Technical Reports Server (NTRS)

    Knox, James; Long, David; Miller, Lee; Thomas, John; Cmarik, Greg; Howard, David

    2016-01-01

    The LDST is a flight experiment demonstration designed to expose current and future candidate carbon dioxide removal system sorbents to an actual crewed space cabin environment to assess and compare sorption working capacity degradation resulting from long term operation. An analysis of sorbent materials returned to earth after approximately one year of operation in the International Space Station's (ISS) Carbon Dioxide Removal Assembly (CDRA) indicated as much as a 70% loss of working capacity of the silica gel desiccant material at the extreme system inlet location, with a gradient of capacity loss down the bed. The primary science objective is to assess the degradation of potential sorbents for exploration class missions and ISS upgrades when operated in a true crewed space cabin environment. A secondary objective is to compare degradation of flight test to a ground test unit with contaminant dosing to determine applicability of ground testing.

  1. Regenerable Sorbent for CO2 Removal

    NASA Technical Reports Server (NTRS)

    Alptekin, Gokhan; Jayaraman, Ambal

    2013-01-01

    A durable, high-capacity regenerable sorbent can remove CO2 from the breathing loop under a Martian atmosphere. The system design allows near-ambient temperature operation, needs only a small temperature swing, and sorbent regeneration takes place at or above 8 torr, eliminating the potential for Martian atmosphere to leak into the regeneration bed and into the breathing loop. The physical adsorbent can be used in a metabolic, heat-driven TSA system to remove CO2 from the breathing loop of the astronaut and reject it to the Martian atmosphere. Two (or more) alternating sorbent beds continuously scrub and reject CO2 from the spacesuit ventilation loop. The sorbent beds are cycled, alternately absorbing CO2 from the vent loop and rejecting the adsorbed material into the environment at a high CO2 partial pressure (above 8 torr). The system does not need to run the adsorber at cryogenic temperatures, and uses a much smaller temperature swing. The sorbent removes CO2 via a weak chemical interaction. The interaction is strong enough to enable CO2 adsorption even at 3 to 7.6 torr. However, because the interaction between the surface adsorption sites and the CO2 is relatively weak, the heat input needed to regenerate the sorbent is much lower than that for chemical absorbents. The sorbent developed in this project could potentially find use in a large commercial market in the removal of CO2 emissions from coal-fired power plants, if regulations are put in place to curb carbon emissions from power plants.

  2. Zinc titanate sorbents

    DOEpatents

    Gupta, Raghubir P.; Gangwal, Santosh K.; Jain, Suresh C.

    1998-01-01

    The present invention provides a zinc titanate sorbent material useful in desulfurization applications. The zinc titanate material is in the form of generally spherical particles of substantially uniform chemical distribution. The sorbent material is capable of absorbing sulfur compounds from a gaseous feed in an amount of at least about 15 weight percent based on the weight of the sorbent. The sorbent material is prepared by a process including: (a) forming a zinc oxide/titanium dioxide dry blend, (b) preparing a substantially uniform aqueous slurry comprising the zinc oxide/titanium dioxide dry blend, organic binder, and at least about 1 weight percent inorganic binder based on the solids weight of the slurry, (c) spray drying the slurry to produce substantially spherical particles, and (d) calcining the particles at a temperature of between about 750.degree. C. to about 950.degree. C. The dry blend is formed by mixing between about 0.5 to about 2 parts zinc oxide having a median particle size of less than about 0.5 .mu., and about 1 part titanium dioxide having a median particle size of less than about 1 .mu.. The slurry contains substantially no free silica and may be prepared by the process including (1) preparing an aqueous solution of organic binder, (2) adding the dry blend to the aqueous solution of organic binder, and (3) adding the inorganic binder to the solution of organic binder, and blend. Additional reagents, such as a surfactant, may also be incorporated into the sorbent material. The present invention also provides a process for desulfurizing a gaseous stream. The process includes passing a gaseous stream through a reactor containing an attrition resistant zinc titanate sorbent material of the present invention.

  3. Zinc titanate sorbents

    DOEpatents

    Gupta, R.P.; Gangwal, S.K.; Jain, S.C.

    1998-02-03

    The present invention provides a zinc titanate sorbent material useful in desulfurization applications. The zinc titanate material is in the form of generally spherical particles of substantially uniform chemical distribution. The sorbent material is capable of absorbing sulfur compounds from a gaseous feed in an amount of at least about 15 weight percent based on the weight of the sorbent. The sorbent material is prepared by a process including: (a) forming a zinc oxide/titanium dioxide dry blend, (b) preparing a substantially uniform aqueous slurry comprising the zinc oxide/titanium dioxide dry blend, organic binder, and at least about 1 weight percent inorganic binder based on the solids weight of the slurry, (c) spray drying the slurry to produce substantially spherical particles, and (d) calcining the particles at a temperature of between about 750 to about 950 C. The dry blend is formed by mixing between about 0.5 to about 2 parts zinc oxide having a median particle size of less than about 0.5 microns, and about 1 part titanium dioxide having a median particle size of less than about 1 micron. The slurry contains substantially no free silica and may be prepared by the process including (1) preparing an aqueous solution of organic binder, (2) adding the dry blend to the aqueous solution of organic binder, and (3) adding the inorganic binder to the solution of organic binder, and blend. Additional reagents, such as a surfactant, may also be incorporated into the sorbent material. The present invention also provides a process for desulfurizing a gaseous stream. The process includes passing a gaseous stream through a reactor containing an attrition resistant zinc titanate sorbent material of the present invention.

  4. Space-filling polyhedral sorbents

    DOEpatents

    Haaland, Peter

    2016-06-21

    Solid sorbents, systems, and methods for pumping, storage, and purification of gases are disclosed. They derive from the dynamics of porous and free convection for specific gas/sorbent combinations and use space filling polyhedral microliths with facial aplanarities to produce sorbent arrays with interpenetrating interstitial manifolds of voids.

  5. Aquatic oil spill cleanup using natural sorbents.

    PubMed

    Paulauskienė, Tatjana; Jucikė, Indrė

    2015-10-01

    One of the most popular transportation methods of crude oil is water transport, leading to potential spills of these pollutants in the seas and oceans and water areas of ports, during their extraction, transportation, transhipment and use. The growth of the Lithuanian economy and the expansion of competitiveness were hardly imagined without the development of the Klaipeda seaport. However, the intensity of shipping and the increase in cargo loading volumes at specialised terminals are associated with a higher risk of environmental pollution. To achieve a sustainable development of the seaport, it is necessary not only to ensure the prevention of potential water pollution but also, if necessary, to use environmentally friendly technology for pollution management. The work analyses the possibilities related to the collection of oil products from the water surface using natural sorbents (peat, wool, moss and straw) and their composites.The research of absorbed amount of crude oil and diesel fuel spilled on the water surface, while using sorbents and their composites, determined that sorbents' composite straw-peat (composition percentage of straw-peat 25-75 %) absorbs the major amount of both crude oil (60 % of the spilled volume) and diesel fuel (69 % of the spilled volume) comparing to single sorbents and sorbents' composite straw-peat (composition percentage of straw-peat 50-50 %).

  6. Aquatic oil spill cleanup using natural sorbents.

    PubMed

    Paulauskienė, Tatjana; Jucikė, Indrė

    2015-10-01

    One of the most popular transportation methods of crude oil is water transport, leading to potential spills of these pollutants in the seas and oceans and water areas of ports, during their extraction, transportation, transhipment and use. The growth of the Lithuanian economy and the expansion of competitiveness were hardly imagined without the development of the Klaipeda seaport. However, the intensity of shipping and the increase in cargo loading volumes at specialised terminals are associated with a higher risk of environmental pollution. To achieve a sustainable development of the seaport, it is necessary not only to ensure the prevention of potential water pollution but also, if necessary, to use environmentally friendly technology for pollution management. The work analyses the possibilities related to the collection of oil products from the water surface using natural sorbents (peat, wool, moss and straw) and their composites.The research of absorbed amount of crude oil and diesel fuel spilled on the water surface, while using sorbents and their composites, determined that sorbents' composite straw-peat (composition percentage of straw-peat 25-75 %) absorbs the major amount of both crude oil (60 % of the spilled volume) and diesel fuel (69 % of the spilled volume) comparing to single sorbents and sorbents' composite straw-peat (composition percentage of straw-peat 50-50 %). PMID:25994272

  7. Enhanced capture of elemental mercury by bamboo-based sorbents.

    PubMed

    Tan, Zengqiang; Xiang, Jun; Su, Sheng; Zeng, Hancai; Zhou, Changsong; Sun, Lushi; Hu, Song; Qiu, Jianrong

    2012-11-15

    To develop cost-effective sorbent for gas-phase elemental mercury removal, the bamboo charcoal (BC) produced from renewable bamboo and KI modified BC (BC-I) were used for elemental mercury removal. The effect of NO, SO2 on gas-phase Hg0 adsorption by KI modified BC was evaluated on a fixed bed reactor using an online mercury analyzer. BET surface area analysis, temperature programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS) were used to determine the pore structure and surface chemistry of the sorbents. The results show that KI impregnation reduced the sorbents' BET surface area and total pore volume compared with that of the original BC. But the BC-I has excellent adsorption capacity for elemental mercury at a relatively higher temperature of 140 °C and 180 °C. The presence of NO or SO2 could inhibit Hg0 capture, but BC-I has strong anti-poisoning ability. The specific reaction mechanism has been further analyzed.

  8. Enhanced capture of elemental mercury by bamboo-based sorbents.

    PubMed

    Tan, Zengqiang; Xiang, Jun; Su, Sheng; Zeng, Hancai; Zhou, Changsong; Sun, Lushi; Hu, Song; Qiu, Jianrong

    2012-11-15

    To develop cost-effective sorbent for gas-phase elemental mercury removal, the bamboo charcoal (BC) produced from renewable bamboo and KI modified BC (BC-I) were used for elemental mercury removal. The effect of NO, SO2 on gas-phase Hg0 adsorption by KI modified BC was evaluated on a fixed bed reactor using an online mercury analyzer. BET surface area analysis, temperature programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS) were used to determine the pore structure and surface chemistry of the sorbents. The results show that KI impregnation reduced the sorbents' BET surface area and total pore volume compared with that of the original BC. But the BC-I has excellent adsorption capacity for elemental mercury at a relatively higher temperature of 140 °C and 180 °C. The presence of NO or SO2 could inhibit Hg0 capture, but BC-I has strong anti-poisoning ability. The specific reaction mechanism has been further analyzed. PMID:22995206

  9. Evaluation of zirconium dioxide-based sorbents to decrease the matrix effect in avocado and almond multiresidue pesticide analysis followed by gas chromatography tandem mass spectrometry.

    PubMed

    Lozano, Ana; Rajski, Łukasz; Uclés, Samanta; Belmonte-Valles, Noelia; Mezcua, Milagros; Fernández-Alba, Amadeo R

    2014-01-01

    Two sorbents containing ZrO₂ (Z-Sep and Z-Sep+) were tested as a d-SPE clean-up in combination with the QuEChERS and ethyl acetate multiresidue method in the pesticide residues extraction in avocado. All extracts were analysed using gas chromatography coupled with a triple quadrupole mass spectrometer working in multi-reaction monitoring mode. GC QToF was used to compare the amount of matrix compounds present in the final extracts, prepared according to different protocols. The highest number of pesticides with acceptable recoveries and the lowest amount of coextracted matrix compounds were provided by QuEChERS with Z-Sep. Subsequently, this method was fully validated in avocado and almonds. Validation studies were carried out according to DG Sanco guidelines including: the evaluation of recoveries at two levels (10 and 50 μg/kg), limit of quantitation, linearity, matrix effects, as well as interday and intraday precision. In avocado, 166 pesticides were fully validated compared to 119 in almonds. The method was operated satisfactorily in routine analysis and was applied to real samples.

  10. Developing Polycation-Clay Sorbents for Efficient Filtration of Diclofenac: Effect of Dissolved Organic Matter and Comparison to Activated Carbon.

    PubMed

    Kohay, Hagay; Izbitski, Avital; Mishael, Yael G

    2015-08-01

    The presence of nanoconcentrations of persistent pharmaceuticals in treated wastewater effluent and in surface water has been frequently reported. A novel organic-inorganic hybrid sorbent based on adsorbing quarternized poly vinylpyridinium-co-styrene (QPVPcS) to montmorillonite (MMT) was designed for the removal of the anionic micropollutants. QPVPcS-clay composites were characterized by X-ray diffraction, FTIR, thermal gravimetric analysis, Zeta potential and element analysis. Based on these measurements polymer-clay micro- and nanostructures, as a function of polymer loading, were suggested. The affinity of the anionic pharmaceutical, diclofenac (DCF), to the composite was high and did not decrease dramatically with an increase of ionic strength, indicating that the interactions are not only electrostatic. The presence of humic acid (HA) did not hinder DCF removal by the composite; whereas, its filtration by granulated activated carbon (GAC) was compromised in the presence of HA. The kinetics and adsorption at equilibrium of DCF to the composite and to GAC were measured and modeled by the time dependent Langmuir equation. The adsorption of DCF to the composite was significantly faster than to GAC. Accordingly, the filtration of micro- and nanoconcentrations of DCF by composite columns, in the presence of HA, was more efficient than by GAC columns. PMID:26126078

  11. [The possibility for obtaining sorbents from the mycelial wastes of antibiotic production].

    PubMed

    Iakubova, A R; Lagunov, V M; Faĭngol'd, Z L

    1995-05-01

    A technological process for production of a sorbent based on the mycelial waste of penicillin manufacture was developed. The process and its parameters are described. The exploitation conditions determine whether a strong sorbent with low sorption properties or a sorbent with higher sorption properties and lower granule strength is prepared.

  12. Sorption ability of the composite sorbent for water treatment from radioactive elements

    NASA Astrophysics Data System (ADS)

    Gonets, A. V.; Chubik, M. P.; Chubik, M. V.; Tretyakov, A. N.

    2015-10-01

    The goal of research is to develop the composite sorbent with application of various metal oxides nanoforms and nonpathogenic mold fungi mycelium modified by these nanoforms. This article describes the producing method of the composite sorbent and the research results of the sorbent sorption ability while the sorption process conditions are changed.

  13. Inorganic ion sorbent method

    DOEpatents

    Teter, David M.; Brady, Patrick V.; Krumhansl, James L.

    2007-07-17

    A process and medium for decontamination of water containing anionic species including arsenic and chromium, wherein compounds comprising divalent and trivalent metal oxides and sulfides are used to form surface complexes with contaminants under pH conditions within the range of potable water. In one embodiment natural and synthetic spinels and spinel-like materials are used as the sorbent substance.

  14. Inorganic ion sorbents

    DOEpatents

    Teter, David M.; Brady, Patrick V.; Krumhansl, James L.

    2006-10-17

    A process and medium for decontamination of water containing anionic species including arsenic and chromium, wherein compounds comprising divalent and trivalent metal oxides and sulfides are used to form surface complexes with contaminants under pH conditions within the range of potable water. In one embodiment natural and synthetic spinels and spinel-like materials are used as the sorbent substance.

  15. VAP Development: Initiation, Development, Evaluation, and Release

    SciTech Connect

    Jensen, M; Collis, Fast, J; Flynn, C; Mather, J; McFarlane, S; Monroe, J; Sivaraman, C; Xie, S

    2011-02-23

    This white paper provides a plan to formalize the evaluation of newly developed VAPs and a framework for the development of value-added products through four different stages: Initiation, Development, Evaluation, and Release.

  16. Bench-Scale Testing of Attrition Resistant Moving Bed Sorbents

    SciTech Connect

    Swisher, J.H.; Gupta, R.P.

    1996-12-31

    Integrated Gasification Combined Cycle (IGCC) systems with cold-gas cleanup have now reached the early stages of commercialization. The foundation for this was successful completion of the Cool Water Coal Gasification Program several years ago. Destec Energy, Inc., a subsidiary of Dow Chemical Company, has a plant in operation in Louisiana, and the 2 Wabash River Plant in Indiana is now starting up. A similar plant based on the Shell gasification technology is operating in the Netherlands. In two new plants now under construction, the Tampa Electric Plant in Florida and the Sierra Pacific Power Plant in Nevada, incorporating hot-gas cleanup technology is desirable. Unfortunately, some nagging problems remain with both sulfur sorbent and particle filter technology that may result in the use of cold-gas, rather than hot-gas, cleanup in these plants. With sulfur sorbents, the main problems are with mechanical property degradation and/or loss of sulfur capacity over many sulfidation-regeneration cycles. The sorbents receiving the most attention are all zinc based. They include various zinc titanate formulations and proprietary materials developed by the U.S. Department of Energy/Morgantown Energy Technology Center (DOE/METC) staff and the Phillips Petroleum Company. The investigators on this project are now completing their third year of effort on a superstrong zinc titanate sorbent. Prior to this year, various formulations were prepared and evaluated for their potential use in fixed- and fluidized-bed hot-gas desulfurization systems. A unique feature, the reason for the high strength, is that the zinc titanate is contained in a matrix of titanium dioxide. Its crush strength is more than 6 times that prior investigators achieved.

  17. Evaluation of alternative sorbents for dispersive solid-phase extraction clean-up in the QuEChERS method for the determination of pesticide residues in rice by liquid chromatography with tandem mass spectrometry.

    PubMed

    Cabrera, Liziara da C; Caldas, Sergiane S; Prestes, Osmar D; Primel, Ednei G; Zanella, Renato

    2016-05-01

    Many compounds are used for pest control during the production and storage of rice, making it necessary to employ multiclass methods for pesticide residues determination. For this purpose, QuEChERS-based methods are very efficient, fast and accurate, and improvements in the clean-up step are important, especially for complex matrices, like cereals. In this work, different sorbents such as chitosan, florisil(®) , alumina, diatomaceous earth, graphitized carbon black, besides the commonly used primary secondary amine and octadecylsilane, were evaluated for dispersive solid-phase extraction clean-up in acetate-buffered QuEChERS method for the determination of residues of 20 representative pesticides and one metabolite in rice by liquid chromatography coupled to tandem mass spectrometry. The sorbent C18 presented the best results, however, chitosan showed similar results, and the best performance among the unconventional sorbents evaluated. The method limit of quantification, attending accuracy (70-120% recovery) and precision (RSD ≤20%) criteria, ranged from 5 to 20 μg/kg. Results showed that chitosan is an effective alternative to reduce analysis costs, maintaining the method reliability and accuracy.

  18. Characterization and optimization of sorbents utilized for emission control during coal gasification. 1997 Fourth quarter research report, October 1, 1997--December 31, 1997

    SciTech Connect

    Huque, Z.; Mei, D.; Zhou, J.

    1997-12-31

    Advanced integrated gasification combined cycle and pressurized fluidized bed combustion power system requires both hot gas desulfurization and particulate filtration to improve system thermal efficiency and overall performance. Few metal oxides were evaluated to be the sorbent candidate for hot gas desulfurization process. The use of waste iron oxide as a disposable metal oxide sorbent will alleviate the constraints imposed on iron oxides including the degradation of sulfur capacity and its physical attrition required for a regenerable sorbent. The very low cost of waste iron oxides and the elimination of the investment associated with sorbent regeneration make it attractive to replace currently developed sorbent candidates. However, the use of waste iron oxides indicates a significant increase of dust loading for particulate filtration. The slower the reaction rate the iron oxide and coal ash mixture is, the longer residence time and higher iron oxide to coal ratio are required. One of the key issue of the use of waste iron oxides as a disposable sorbent material relies on the capability of particulate filtration efficiency. The current back pulse cleaning of the dust cake had been evaluated; and the preliminary test results indicated that the simultaneous operation of hot gas desulfurization and particulate filtration is feasible. A parametric testing will be performed on hot gas desulfurization and particulate independently first. The independent test results will help optimize the test design and evaluation of the integration of hot gas desulfurization testing and particulate filtration testing to be completed in the first two quarters 1998.

  19. Enhanced durability of desulfurization sorbents for fluidized-bed applications

    SciTech Connect

    Gupta, R.P.; Gangwal, S.K.

    1991-06-01

    Advanced integrated gasification combined cycle (IGCC) power systems require the development of high-temperature desulfurization sorbents capable of removing hydrogen sulfide from coal gasifier down to very low levels. The objective of this investigation was to identify and demonstrate methods for enhancing the long-term chemical reactivity and mechanical strength of zinc ferrite, a leading regenerable sorbent, for fluidized-bed applications. Fluidized sorbent beds offer significant potential in IGCC systems because of their ability to control the highly exothermic regeneration involved. However, fluidized beds require a durable, attrition-resistant sorbent in the 100--300 {mu}m size range. A bench-scale high-temperature, high- pressure (HTHP) fluidized-bed reactor (7.6-cm I.D.) system capable of operating up to 24 atm and 800{degree}C was designed, built and tested. A total of 175 sulfidation-regeneration cycles were carried out using KRW-type coal gas with various zinc ferrite formulations. A number of sorbent manufacturing techniques including spray drying, impregnation, crushing and screening, and granulation were investigated. While fluidizable sorbents prepared by crushing durable pellets and screening had acceptable sulfur capacity, they underwent excessive attrition during multicycle testing. The sorbent formulations prepared by a proprietary technique were found to have excellent attrition resistance and acceptable chemical reactivity during multicycle testing. However, zinc ferrite was found to be limited to 550{degree}C, beyond which excessive sorbent weakening due to chemical transformations, e.g., iron oxide reduction, was observed.

  20. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect

    Jha, M.C.; Berggren, M.H.

    1987-10-27

    AMAX Research Development Center (AMAX R D) has been investigating methods for improving the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hog coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. The reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point in a bench-scale fixed-bed reactor. The durability may be defined as the ability of the sorbent to maintain its reactivity and other important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and regeneration. Two base case sorbents, spherical pellets and cylindrical extrudes used in related METC sponsored projects, are being used to provide a basis for the comparison of physical characteristics and chemical reactivity.

  1. Trace-Metal Scavenging from Biomass Syngas with Novel High-Temperature Sorbents

    SciTech Connect

    Gale, Thomas K.; Walsh, Pete M.

    2007-03-21

    Effective syngas cleanup is one of the remaining major technical challenges yet to be resolved and one that will provide the most benefit to the suite of bio-thermochemical process technologies. Beyond tars and acid gases, which are themselves a significant detriment to reforming catalysts and associated equipment, semi-volatile metals can also damage cleanup systems, catalysts, and contaminate the fungible products. Metals are a difficult challenge to deal with whether using hot-gas filtration or low-temperature processing. Even though most of the metal tends to condense before the barrier filter of hot-gas cleanup systems, some small percentage of the metal (large enough to damage syngas-reforming catalysts, the candle filters themselves, and gas turbine blades) does pass through these barrier filters along with the clean syngas. Low-temperature processing requires expensive measures to remove metals from the process stream. Significant costs are required to remove these metals and if they are not removed before contacting the catalyst, they will significantly reduce the life of the catalyst. One approach to solving the metals problem is to use high-temperature sorbents to capture all of the semi-volatile metals upstream of the barrier filter, which would prevent even small amounts of metal from passing through the filter with the clean syngas. High Temperature sorbents have already been developed that have been shown to be effective at capturing semi-volatile metals from vitiated combustion effluent, i.e., high-temperature flue gas. The objective on this project was to evaluate these same sorbents for their ability to scavenge metals from inert, reducing, and real syngas environments. Subsequently, it was the objective of this project to develop designer sorbents and an injection technology that would optimize the effectiveness of these sorbents at capturing metals from syngas, protecting the barrier filters from damage, and protecting the catalysts and other

  2. Suspension column for recovery and separation of substances using ultrasound-assisted retention of bead sorbents.

    PubMed

    Spivakov, Boris Ya; Shkinev, Valeriy M; Danilova, Tatiana V; Knyazkov, Nikolai N; Kurochkin, Vladimir E; Karandashev, Vasiliy K

    2012-12-15

    A novel approach to sorption recovery and separation of different substances is proposed which is based on the use of suspended bead sorbents instead of conventional packed beds of such sorbents. This makes it possible to employ small-sized beads which are trapped in a low-pressure column due to ultrasound-assisted retention, without any frits to hold the sorption material. A flow system including a separation mini-column, named herein a suspension column, has been developed and tested by the studies of solid phase extraction (SPE) of trace metals from bi-distilled water and sea water using a 150-μL column with a silica-based sorbent containing iminodiacetic groups (DIAPAK IDA) and having a grain size of 6 μm. The adsorption properties of DIAPAK IDA suspension (9.5mg) were evaluated through adsorption/desorption experiments, where the effect of solution pH and eluent on the SPE of trace metals were examined by ICP-MS or ICP-AES measurements. When sample solution was adjusted to pH 8.0 and 1 mol L(-1) nitric acid was used as eluent, very good recoveries of more than 90% were obtained for a number of elements in a single-step extraction. To demonstrate the versatility of the approach proposed and to show another advantage of ultrasonic field (acceleration of sorbate/sorbent interaction), a similar system was used for heterogeneous immunoassays of some antigens in ultrasonic field using agarose sorbents modified by corresponding antibodies. It has been shown that immunoglobulins, chlamidia, and brucellos bacteria can be quantitatively adsorbed on 15-μm sorbent (15 particles in 50 μL) and directly determined in a 50-μL mini-chamber using fluorescence detection. PMID:23182579

  3. Modified clay sorbents

    DOEpatents

    Fogler, H. Scott; Srinivasan, Keeran R.

    1990-01-01

    A novel modified clay sorbent and method of treating industrial effluents to remove trace pollutants, such as dioxins, biphenyls, and polyaromatics such as benzo(a)pyrene and pentachlorophenol. The novel clay sorbent has a composite structure in which the interlayer space of an expandable clay, such as smectite, is filled with polyvalent or multivalent inorganic cations which forces weaker surfactant cations to locate on the surface of the clay in such an orientation that the resulting composite is hydrophilic in nature. A specific example is cetylpyridinium-hydroxy aluminum-montmorillonite. In certain embodiments, a non-expanding clay, such as kaolinite, is used and surfactant cations are necessarily located on an external surface of the clay. A specific example is cetylpyridinium-kaolinite.

  4. DEVELOPMENT AND EVALUATION OF NANOSCALE SORBENTS FOR MERCURY CAPTURE FROM WARM FUEL GAS

    SciTech Connect

    Raja A. Jadhav; Howard Meyer

    2005-01-01

    The Mercury Testing Experimental System available in GTI's Hot Gas Cleanup laboratory was prepared for the project. As part of the shakedown testing, the system was checked for possible gas leaks and fixed. In addition, the mass flow controller was calibrated for diluent N{sub 2} stream. A major part of the shakedown testing was the calibration of the semi-continuous mercury analyzer and the verification of the permeation rate of the mercury permeation tube. It was found that the analyzer's mercury concentration measurements were much lower than expected from the permeation tube rate calculations. Vendors of the analyzer and the permeation tube are contacted to find out the reason for this discrepancy.

  5. Development and characterization of a nanodendritic silver-based solid-phase extraction sorbent for selective enrichment of endocrine-disrupting chemicals in water and milk samples.

    PubMed

    Gao, Yuanji; Xia, Bing; Liu, Jie; Ji, Baocheng; Ma, Fengwei; Ding, Lisheng; Li, Bangjing; Zhou, Yan

    2015-11-01

    In this study, 4-[4-phenylazo-phenoxy] butyl-1-thiol (AzSH) functionalized nanodendritic silver (AzS@AgNDs) materials were prepared as a solid-phase extraction (SPE) sorbent for the selective extraction of estrogens. AzS@AgNDs possess an extremely large surface-to-volume ratio and a small average particle size. The performance of the material was evaluated by selective enrichment of hexestrol, diethylstilbestrol, dienestrol and bisphenol A in water and milk samples followed by rapid ultra-performance liquid chromatography-electrospray ionization mass spectrometry (UPLC-ESI-MS) analyses. The results exhibited that AzS@AgNDs had excellent adsorption capability for the targeted estrogens. The limits of detection of the four estrogens ranged from 0.1 to 5.0 pg/mL. The recoveries of the estrogens spiked into tap water were over the range of 83.6-105.3% with relative standard deviations of 2.8-6.0%. The results indicated the capability of this method for the rapid determination of estrogens in milk and other environmental water samples. In addition, this method would be useful for the determination of human exposure and health risk assessments trace level of endocrine-disrupting compounds (EDCs) in drinking water.

  6. Development and characterization of a nanodendritic silver-based solid-phase extraction sorbent for selective enrichment of endocrine-disrupting chemicals in water and milk samples.

    PubMed

    Gao, Yuanji; Xia, Bing; Liu, Jie; Ji, Baocheng; Ma, Fengwei; Ding, Lisheng; Li, Bangjing; Zhou, Yan

    2015-11-01

    In this study, 4-[4-phenylazo-phenoxy] butyl-1-thiol (AzSH) functionalized nanodendritic silver (AzS@AgNDs) materials were prepared as a solid-phase extraction (SPE) sorbent for the selective extraction of estrogens. AzS@AgNDs possess an extremely large surface-to-volume ratio and a small average particle size. The performance of the material was evaluated by selective enrichment of hexestrol, diethylstilbestrol, dienestrol and bisphenol A in water and milk samples followed by rapid ultra-performance liquid chromatography-electrospray ionization mass spectrometry (UPLC-ESI-MS) analyses. The results exhibited that AzS@AgNDs had excellent adsorption capability for the targeted estrogens. The limits of detection of the four estrogens ranged from 0.1 to 5.0 pg/mL. The recoveries of the estrogens spiked into tap water were over the range of 83.6-105.3% with relative standard deviations of 2.8-6.0%. The results indicated the capability of this method for the rapid determination of estrogens in milk and other environmental water samples. In addition, this method would be useful for the determination of human exposure and health risk assessments trace level of endocrine-disrupting compounds (EDCs) in drinking water. PMID:26572841

  7. Utilization of silkworm cocoon waste as a sorbent for the removal of oil from water.

    PubMed

    Moriwaki, Hiroshi; Kitajima, Shiori; Kurashima, Masahiro; Hagiwara, Ayaka; Haraguchi, Kazuma; Shirai, Koji; Kanekatsu, Rensuke; Kiguchi, Kenji

    2009-06-15

    The aim of this study is to investigate the utilization of silkworm cocoon waste, such as pierced or stained cocoons, as a sorbent material for the removal of motor and vegetable oils from water. The oil-sorption capacity, rate and reusability of the material were evaluated. The results show the high sorption capacity of the silkworm cocoon waste sorbent (42-52 g(oil)/g(sorbent) for motor oil and 37-60 g(oil)/g(sorbent) for vegetable oil). The oil sorbed onto the material could be recovered by squeezing the sorbent, and the squeezed material showed an oil-sorption capacity over 15 g(oil)/g(sorbent). We concluded that the material shows a high performance as a low cost and environmental friendly sorbent for the removal of oil from water.

  8. Measurement of VOCs Using Passive Sorbent Tubes near Oil & Natural Gas Production Pads in Colorado and Texas

    EPA Science Inventory

    A U.S. EPA team, consisting of the Office of Research and Development and Region 6 (Dallas) and Region 8 (Denver), deployed passive-diffusive sorbent tubes as part of a method evaluation study around one oil and natural gas production pad in both the Barnett Shale Basin in Texas ...

  9. A long life ZnO-TiO{sub 2} sorbent

    SciTech Connect

    Karpuk, M.E.; Copeland, R.J.; Cesario, M.; Dubovik, M.; Feinberg, D.; Windecker, B.

    1995-11-01

    The objective of this Phase 1 SBIR was to develop and test a long life ZnO-TiO{sub 2} sorbent for hot gas cleanup. Specifically, the authors measured the sulfur loading at space velocities typically used for absorption of H{sub 2}S and regenerated the sorbent with diluted air containing SO{sub 2} for multiple cycles. Based on the experimental results, they prepare a conceptual design of the sorbent fabrication system, and estimated the cost of producing the sorbent and the cost of sulfur removal. Results are presented on tests of sorbents identified as TMZ-6 and TMZ-6II.

  10. Sorbent-Based Gas Phase Air Cleaning for VOCs in CommercialBuildings

    SciTech Connect

    Fisk, William J.

    2006-05-01

    This paper provides a review of current knowledge about the suitability of sorbent-based air cleaning for removing volatile organic compounds (VOCs) from the air in commercial buildings as needed to enable reductions in ventilation rates and associated energy savings. The fundamental principles of sorbent air cleaning are introduced, criteria are suggested for sorbent systems that can counteract indoor VOC concentration increases from reduced ventilation, major findings from research on sorbent performance for this application are summarized, novel sorbent technologies are described, and related priority research needs are identified. Major conclusions include: sorbent systems can remove a broad range of VOCs with moderate to high efficiency, sorbent technologies perform effectively when challenged with VOCs at the low concentrations present indoors, and there is a large uncertainty about the lifetime and associated costs of sorbent air cleaning systems when used in commercial buildings for indoor VOC control. Suggested priority research includes: experiments to determine sorbent system VOC removal efficiencies and lifetimes considering the broad range and low concentration of VOCs indoors; evaluations of in-situ regeneration of sorbents; and an updated analysis of the cost of sorbent air cleaning relative to the cost of ventilation.

  11. JV Task 5 - Evaluation of Residual Oil Fly Ash As A Mercury Sorbent For Coal Combustion Flue Gas

    SciTech Connect

    Robert Patton

    2006-12-31

    The mercury adsorption capacity of a residual oil fly ash (ROFA) sample collected form Florida Power and Light Company's Port Everglades Power Plant was evaluated using a bituminous coal combustion flue gas simulator and fixed-bed testing protocol. A size-segregated (>38 {micro}g) fraction of ROFA was ground to a fine powder and brominated to potentially enhance mercury capture. The ROFA and brominated-ROFA were ineffective in capturing or oxidizing the Hg{sup 0} present in a simulated bituminous coal combustion flue gas. In contrast, a commercially available DARCO{reg_sign} FGD initially adsorbed Hg{sup 0} for about an hour and then catalyzed Hg{sup 0} oxidation to produce Hg{sup 2+}. Apparently, the unburned carbon in ROFA needs to be more rigorously activated in order for it to effectively capture and/or oxidize Hg{sup 0}.

  12. An attrition-resistant zinc titanate sorbent for sulfur. Final technical report, September 1, 1992--August 31, 1993

    SciTech Connect

    Swisher, J.H.

    1993-12-31

    In the continuing search for good sorbent materials to remove sulfur for hot, coal-derived gases, zinc titanate sorbents have shown great promise. The objective of this project was to extend the work of prior investigators by developing improvements in the compressive strength and, therefore, the cycle life of these sorbents while maintaining good chemical reactivity. Fifteen formulations were prepared and evaluated. The best properties were obtained by blending relatively course (two micron) ZnO and TiO{sub 2} powders to obtain a composition of 50%Zn{sub 2}TiO{sub 4}-50%TiO{sub 2}. When sintered at 1000{degrees}C, it had a compressive strength of 28 MPa or 147 N/mm, which is four times higher than values obtained by prior investigators. It also performed well in thermogravimetric analysis measurements of reactivity, both in screening tests and in simulated coal gas.

  13. Studies of in-situ calcium based sorbents in advanced pressurized coal conversion systems. Final report, June 1991--October 1994

    SciTech Connect

    Katta, S.; Shires, P.J.; Campbell, W.M.; Henningsen, G.

    1994-10-01

    The overall objective of this project was to obtain experimental data on the reactions of calcium-based sorbents in both air-blown coal gasification systems and second generation fluid bed coal combustion systems (partial gasification) as well as stabilization of the spent sorbent produced. The project consisted of six tasks: Tasks 1 and 2 dealt mostly with project-related activities and preparation of test equipment, Task 3 -- study on sulfidation of calcium-based sorbents, Task 4 -- kinetic studies on calcium-catalyzed carbon gasification reactions, and Task 5 -- oxidation of CaS present in LASHs and DASHs (mixtures of coal ash and limestone or dolomite respectively) to CaSO{sub 4} and absorption of SO{sub 2} on various solids, and Task 6 -- economic evaluation of the most promising CaS oxidation method developed under this program. Experimental studies were conducted primarily to address Task 5 issues, and are discussed in this report.

  14. Aptamer-targeted magnetic nanospheres as a solid-phase extraction sorbent for determination of ochratoxin A in food samples.

    PubMed

    Wu, Ximei; Hu, Jun; Zhu, Binghui; Lu, Lin; Huang, Xiangdong; Pang, Daiwen

    2011-10-14

    A sorbent based on the aptamer for ochratoxin A was immobilized onto magnetic nanospheres (MNS) and used to develop a magnetic solid-phase extraction procedure to clean up food samples in conjunction with high-performance liquid chromatography separation and fluorescence detection. Specific retention of ochratoxin A by the sorbent was demonstrated, and the capacity of the MNS-aptamer sorbent was determined. The efficacy of this new approach was successfully evaluated through comparison with solid-phase extraction on commercial C18 cartridge. Several different food samples fortified in the range of with 2.5-50 μg/kg yielded mean recoveries from 67% to 90%, respectively. Finally, this oligosorbent was applied to the selective extraction of ochratoxin A from unfortified food samples. PMID:21890142

  15. Solid-phase extraction of flavonoids in honey samples using carbamate-embedded triacontyl-modified silica sorbent.

    PubMed

    Liu, Houmei; Zhang, Mingliang; Guo, Yong; Qiu, Hongdeng

    2016-08-01

    In this study, carbamate-embedded triacontyl-modified silica (Sil-CBM-C30) is successfully prepared and used as an efficient sorbent for solid-phase extraction. The extraction performance of the resultant sorbent is evaluated with five flavonoids including myricetin, quercetin, luteolin, kaempferol and isorhamnetin. Main parameters, which affect extraction efficiencies, are carefully investigated and optimized. Comparative experiments between Sil-CBM-C30 and commercial C18 sorbents indicate that the extraction efficiencies of the former one surpass the latter one. The modification of carbamate-embedded triacontyl group on surface of silica causes analytes extracted by hydrophobic, hydrogen bonding and π-π interactions. Under optimal conditions, good linearities and satisfied LODs and LOQs are achieved. The SPE-HPLC-DAD method is successfully developed and applied for the honey sample analysis. PMID:26988475

  16. Determination of polar aromatic amines using newly synthesized sol-gel titanium (IV) butoxide cyanopropyltriethoxysilane as solid phase extraction sorbent.

    PubMed

    Miskam, Mazidatulakmam; Abu Bakar, Nor Kartini; Mohamad, Sharifah

    2014-03-01

    A solid phase extraction (SPE) method has been developed using a newly synthesized titanium (IV) butoxide-cyanopropyltriethoxysilane (Ti-CNPrTEOS) sorbent for polar selective extraction of aromatic amines in river water sample. The effect of different parameters on the extraction recovery was studied using the SPE method. The applicability of the sorbents for the extraction of polar aromatic amines by the SPE was extensively studied and evaluated as a function of pH, conditioning solvent, sample loading volume, elution solvent and elution solvent volume. The optimum experimental conditions were sample at pH 7, dichloromethane as conditioning solvent, 10 mL sample loading volume and 5 mL of acetonitrile as the eluting solvent. Under the optimum conditions, the limit of detection (LOD) and limit of quantification (LOQ) for solid phase extraction using Ti-CNPrTEOS SPE sorbent (0.01-0.2; 0.03-0.61 µg L(-1)) were lower compared with those achieved using Si-CN SPE sorbent (0.25-1.50; 1.96-3.59 µg L(-1)) and C18 SPE sorbent (0.37-0.98; 1.87-2.87 µg L(-1)) with higher selectivity towards the extraction of polar aromatic amines. The optimized procedure was successfully applied for the solid phase extraction method of selected aromatic amines in river water, waste water and tap water samples prior to the gas chromatography-flame ionization detector separation.

  17. Sorbent preparation/modification/additives. Final report, September 1, 1992--November 30, 1993

    SciTech Connect

    Prudich, M.E.; Venkataramakrishnan, R.

    1994-02-01

    Sorbent preparation techniques used today have generally been adapted from techniques traditionally used by the lime industry. Traditional dry hydration and slaking processes have been optimized to produce materials intended for use in the building industry. These preparation techniques should be examined with an eye to optimization of properties important to the SO{sub 2} capture process. The study of calcium-based sorbents for sulfur dioxide capture is complicated by two factors: (1) little is known about the chemical mechanisms by which the standard sorbent preparation and enhancement techniques work, and (2) a sorbent preparation technique that produces a calcium-based sorbent that enjoys enhanced calcium utilization in one regime of operation [flame zone (>2400 F), in-furnace (1600--2400 F), economizer (800--1100 F), after air preheater (<350 F)] may not produce a sorbent that enjoys enhanced calcium utilization in the other reaction zones. Again, an in-depth understanding of the mechanism of sorbent enhancement is necessary if a systematic approach to sorbent development is to be used. As a long-term goal, an experimental program is being carried out for the purpose of (1) defining the effects of slaking conditions on the properties of calcium-based sorbents, (2) determining how the parent limestone properties of calcium-based sorbents, and (3) elucidating the mechanism(s) relating to the activity of various dry sorbent additives. An appendix contains a one-dimensional duct injection model with modifications to handle the sodium additives.

  18. Potential hazards of brominated carbon sorbents for mercury emission control.

    PubMed

    Bisson, Teresa M; Xu, Zhenghe

    2015-02-17

    Mercury is a toxic air pollutant, emitted from the combustion of coal. Activated Carbon (AC) or other carbon sorbent (CS) injection into coal combustion flue gases can remove elemental mercury through an adsorption process. Recently, a brominated CS with biomass ash as the carbon source (Br-Ash) was developed as an alternative for costly AC-based sorbent for mercury capture. After mercury capture, these sorbents are disposed in landfill, and the stability of bromine and captured mercury is of paramount importance. The objective of this study is to determine the fate of mercury and bromine from Br-Ash and brominated AC after their service. Mercury and bromine leaching tests were conducted using the standard toxicity characteristic leaching procedure (TCLP). The mercury was found to be stable on both the Br-Ash and commercial brominated AC sorbents, while the bromine leached into the aqueous phase considerably. Mercury pulse injection tests on the sorbent material after leaching indicate that both sorbents retain significant mercury capture capability even after the majority of bromine was removed. Testing of the Br-Ash sorbent over a wider range of pH and liquid:solid ratios resulted in leaching of <5% of mercury adsorbed on the Br-Ash. XPS analysis indicated more organically bound Br and less metal-Br bonds after leaching.

  19. Developing a Small-scale De-fluoridation Filter for use in Rural Northern Ghana with Activated Alumina as the Sorbent

    NASA Astrophysics Data System (ADS)

    Craig, L.; Stillings, L. L.; Decker, D.; Thomas, J.

    2013-12-01

    In northern Ghana, groundwater is the main source of household water and is generally considered a safe and economical source of drinking water. However in some areas it contains fluoride (F-) concentrations above the 1.5 ppm limit recommended by the World Health Organization, putting the users at risk of fluorosis. The study area in the Upper East Region of northern Ghana has pockets of groundwater F- up to 4.6 ppm and, as a result, also has a high percentage of residents with dental fluorosis. They have no alternative water source and, because of the poverty and limited access to technology, the affected community lacks the capacity to set up advanced treatment systems. One proposed solution is to attach F- adsorption filters to the wells, since adsorption is considered a simple and cost effective approach for treating high F- drinking water. This study evaluates activated alumina as a sorbent for use in de-fluoridation filters in the study area. We evaluated the long-term adsorption capacity of activated alumina, as well as potential changes in F- adsorption rate and capacity with grain size. We measured differences in positive surface charge (as C m-2) via slow acid titration, as well as F- loading with varied prior hydration time. Experimental results from this research show no notable change in F- adsorption or positive surface charge when the activated alumina surface was pre-equilibrated in distilled water from 24 hours up to 30 weeks before the experiment. The results of F- loading show a maximum of ~3.4 mg F- sorbed per gm activated alumina (at initial pH ~6.9, initial F- 1 to 60 ppm, and 20 hr reaction time). The pH dependent surface charge shows a maximum of ~0.14 C m-2 at pH of ~4.4 and zero surface charge at pH ~8.5. F- loading experiments were conducted with grain size ranges 0.125 to 0.250 mm and 0.5 to 1.0 mm to evaluate changes in F- adsorption rate (initial pH ~6.9, initial F- 10 ppm) and F- loading (initial pH ~6.9, initial F- 1 to 60 ppm, 20 hr

  20. Developing a Small-Scale De-Fluoridation Filter for Use in Rural Northern Ghana with Activated Alumina As the Sorbent

    NASA Astrophysics Data System (ADS)

    Craig, L.; Stillings, L. L.

    2014-12-01

    In northern Ghana, groundwater is the main source of household water and is generally considered safe to drink. However in some areas it contains fluoride (F-) concentrations above the 1.5 ppm limit recommended by the World Health Organization, putting the users at risk of fluorosis. The study area in the Upper East Region of Ghana has pockets of groundwater F- up to 4.6 ppm and, as a result, also has a high percentage of residents with dental fluorosis. They have no alternative water source and, because of poverty and limited access to technology, lack the capacity to set up advanced treatment systems. One proposed solution is to attach F- adsorption filters to the wells, since adsorption is considered a simple and cost effective approach for treating high F-drinking water. This study evaluates activated alumina as a sorbent for use in de-fluoridation filters in the study area. We evaluated the long-term adsorption capacity of activated alumina, and changes in F- adsorption rate and capacity with grain size. We measured differences in positive surface charge (C m-2) via slow acid titration, as well as F- loading with varied prior hydration time. Results from this research show no notable change in F- adsorption or positive surface charge when the activated alumina surface was pre-equilibrated in distilled water from 24 hours to 30 weeks. The results of F- loading show a maximum of ~3.4 mg F- sorbed per gm activated alumina (initial pH ~6.9, initial F- 1 to 60 ppm, 20 hr reaction time). The pH dependent surface charge is ~0.14 C m-2 at pH of ~4.4 and is zero at pH ~8.6. F- loading experiments were conducted with grain size 0.125 to 0.250 mm and 0.5 to 1.0 mm to evaluate changes in F- adsorption rate (initial pH ~6.9, initial F- 10 ppm) and F- loading (initial pH ~6.9, initial F- 1 to 60 ppm, 20 hr reaction time). The F- loading did not change with grain size. However time to equilibrium increased dramatically with a decrease in grain size - after one hour of

  1. A Low Cost, High Capacity Regenerable Sorbent for Pre-combustion CO{sub 2} Capture

    SciTech Connect

    Alptekin, Gokhan

    2012-09-30

    The overall objective of the proposed research is to develop a low cost, high capacity CO{sub 2} sorbent and demonstrate its technical and economic viability for pre-combustion CO{sub 2} capture. The specific objectives supporting our research plan were to optimize the chemical structure and physical properties of the sorbent, scale-up its production using high throughput manufacturing equipment and bulk raw materials and then evaluate its performance, first in bench-scale experiments and then in slipstream tests using actual coal-derived synthesis gas. One of the objectives of the laboratory-scale evaluations was to demonstrate the life and durability of the sorbent for over 10,000 cycles and to assess the impact of contaminants (such as sulfur) on its performance. In the field tests, our objective was to demonstrate the operation of the sorbent using actual coal-derived synthesis gas streams generated by air-blown and oxygen-blown commercial and pilot-scale coal gasifiers (the CO{sub 2} partial pressure in these gas streams is significantly different, which directly impacts the operating conditions hence the performance of the sorbent). To support the field demonstration work, TDA collaborated with Phillips 66 and Southern Company to carry out two separate field tests using actual coal-derived synthesis gas at the Wabash River IGCC Power Plant in Terre Haute, IN and the National Carbon Capture Center (NCCC) in Wilsonville, AL. In collaboration with the University of California, Irvine (UCI), a detailed engineering and economic analysis for the new CO{sub 2} capture system was also proposed to be carried out using Aspen PlusTM simulation software, and estimate its effect on the plant efficiency.

  2. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect

    Berggren, M.H.; Jha, M.C.

    1989-10-01

    AMAX Research Development Center (AMAX R D) investigated methods for enhancing the reactivity and durability of zinc ferrite desulfurization sorbents. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For this program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and oxidation. Two base case sorbents, a spherical pellet and a cylindrical extrude used in related METC-sponsored projects, were used to provide a basis for the aimed enhancement in durability and reactivity. Sorbent performance was judged on the basis of physical properties, single particle kinetic studies based on thermogravimetric (TGA) techniques, and multicycle bench-scale testing of sorbents. A sorbent grading system was utilized to quantify the characteristics of the new sorbents prepared during the program. Significant enhancements in both reactivity and durability were achieved for the spherical pellet shape over the base case formulation. Overall improvements to reactivity and durability were also made to the cylindrical extrude shape. The primary variables which were investigated during the program included iron oxide type, zinc oxide:iron oxide ratio, inorganic binder concentration, organic binder concentration, and induration conditions. The effects of some variables were small or inconclusive. Based on TGA studies and bench-scale tests, induration conditions were found to be very significant.

  3. Evaluation in Human Resource Development.

    ERIC Educational Resources Information Center

    1999

    These four papers are from a symposium on evaluation in human resource development (HRD). "Assessing Organizational Readiness for Learning through Evaluative Inquiry" (Hallie Preskill, Rosalie T. Torres) reviews how evaluative inquiry can facilitate organizational learning; argues HRD evaluation should be reconceptualized as a process for…

  4. Fixing atmospheric CO2 by environment adaptive sorbent and renewable energy

    NASA Astrophysics Data System (ADS)

    Wang, T.; Liu, J.; Ge, K.; Fang, M.

    2014-12-01

    Fixing atmospheric CO2, followed by geologic storage in remote areas is considered an environmentally secure approach to climate mitigation. A moisture swing sorbent was investigated in the laboratory for CO2 capture at a remote area with humid and windy conditions. The energy requirement of moisture swing absorption could be greatly reduced compared to that of traditional high-temperature thermal swing, by assuming that the sorbent can be naturally dried and regenerated at ambient conditions. However, for currently developed moisture swing materials, the CO2 capacity would drop significantly at high relative humidity. The CO2 capture amount can be reduced by the poor thermodynamics and kinetics at high relative humidity or low temperature. Similar challenges also exist for thermal or vacuum swing sorbents. Developing sorbent materials which adapt to specific environments, such as high humidity or low temperature, can ensure sufficient capture capacity on the one hand, and realize better economics on the other hand (Figure 1) .An environment adaptive sorbent should have the abilities of tunable capacity and fast kinetics at extreme conditions, such as high humidity or low temperature. In this presentation, the possibility of tuning CO2 absorption capacity of a polymerized ionic liquid material is discussed. The energy requirement evaluation shows that tuning the CO2 binding energy of sorbent, rather than increasing the temperature or reducing the humidity of air, could be much more economic. By determining whether the absorption process is controlled by physical diffusion controlled or chemical reaction, an effective approach to fast kinetics at extreme conditions is proposed. A shrinking core model for mass transfer kinetics is modified to cope with the relatively poor kinetics of air capture. For the studied sample which has a heterogeneous structure, the kinetic analysis indicates a preference of sorbent particle size optimization, rather than support layer

  5. CAN SORBENT-BASED GAS PHASE AIR CLEANING FOR VOCS SUBSTITUTE FOR VENTILATION IN COMMERCIAL BUILDINGS?

    SciTech Connect

    Fisk, William; Fisk, William J.

    2007-08-01

    This paper reviews current knowledge about the suitability of sorbent-based air cleaning for removing volatile organic compounds (VOCs) from the air in commercial buildings, as needed to enable reductions in ventilation rates and associated energy savings. The principles of sorbent air cleaning are introduced, criteria are suggested for sorbent systems that can counteract indoor VOC concentration increases from reduced ventilation, major findings from research on sorbent performance for this application are summarized, and related priority research needs are identified. Major conclusions include: sorbent systems can remove a broad range of VOCs with moderate to high efficiency, sorbent technologies perform effectively when challenged with VOCs at the low concentrations present indoors, and there is a large uncertainty about the lifetime and associated costs of sorbent air cleaning systems when used in commercial buildings for indoor VOC control. Suggested priority research includes: experiments to determine sorbent system VOC removal efficiencies and lifetimes considering the broad range and low concentration of VOCs indoors; evaluations of in-situ regeneration of sorbents; and an updated analysis of the cost of sorbent air cleaning relative to the cost of ventilation.

  6. Sorbent-based sampling methods for volatile and semi-volatile organic compounds in air Part 1: Sorbent-based air monitoring options.

    PubMed

    Woolfenden, Elizabeth

    2010-04-16

    Sorbent tubes/traps are widely used in combination with gas chromatographic (GC) analytical methods to monitor the vapour-phase fraction of organic compounds in air. Target compounds range in volatility from acetylene and freons to phthalates and PCBs and include apolar, polar and reactive species. Airborne vapour concentrations will vary depending on the nature of the location, nearby pollution sources, weather conditions, etc. Levels can range from low percent concentrations in stack and vent emissions to low part per trillion (ppt) levels in ultra-clean outdoor locations. Hundreds, even thousands of different compounds may be present in any given atmosphere. GC is commonly used in combination with mass spectrometry (MS) detection especially for environmental monitoring or for screening uncharacterised workplace atmospheres. Given the complexity and variability of organic vapours in air, no one sampling approach suits every monitoring scenario. A variety of different sampling strategies and sorbent media have been developed to address specific applications. Key sorbent-based examples include: active (pumped) sampling onto tubes packed with one or more sorbents held at ambient temperature; diffusive (passive) sampling onto sorbent tubes/cartridges; on-line sampling of air/gas streams into cooled sorbent traps; and transfer of air samples from containers (canisters, Tedlar) bags, etc.) into cooled sorbent focusing traps. Whichever sampling approach is selected, subsequent analysis almost always involves either solvent extraction or thermal desorption (TD) prior to GC(/MS) analysis. The overall performance of the air monitoring method will depend heavily on appropriate selection of key sampling and analytical parameters. This comprehensive review of air monitoring using sorbent tubes/traps is divided into 2 parts. (1) Sorbent-based air sampling option. (2) Sorbent selection and other aspects of optimizing sorbent-based air monitoring methods. The paper presents

  7. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Volume 2, Single particle kinetic studies of sulfidation and regeneration reactions of candidate zinc ferrite sorbents

    SciTech Connect

    Silaban, A.; Harrison, D.P.

    1989-05-02

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  8. Development of sintering-resistant CaO-based sorbent derived from eggshells and bauxite tailings for cyclic CO2 capture.

    PubMed

    Shan, ShaoYun; Ma, AiHua; Hu, YiCheng; Jia, QingMing; Wang, YaMing; Peng, JinHui

    2016-01-01

    Carbon dioxide, one of the major greenhouse gases, are believed to be a major contributor to global warming. As a consequence, it is imperative for us to control and remove CO2 emissions. The CaO, a kind of effective CO2 sorbent at high temperature, has attracted increasing attention due to some potential advantages. The main drawback in practical application is the deterioration of CO2 capture capacity following multiples cycles. In the present study, novel low-cost porous CaO-based sorbents with excellent CO2 absorption-desorption performance were synthesized using bauxite tailings (BTs) and eggshells as raw materials via solid-phase method. Effect of different BTs content on CO2 absorption-desorption properties was investigated. Phase composition and morphologies were analyzed by XRD and SEM, and CO2 absorption properties were investigated by the simultaneous thermogravimetric analyzer. The as-prepared CaO-based sorbent doped with 10 wt% BTs showed superior CO2 absorption stability during multiple absorption-desorption cycles, with being >55% conversion after 40 cycles. This improved CO2 absorption performance was attributed to the particular morphologies of the CaO-based sorbents. Additionally, during absorption-desorption cycles the occurrence of Ca12Al14O33 phase is considered to be responsible for the excellent CO2 absorption performance of CaO-based sorbents. In the meanwhile, the use of solid waste eggshell and BTs not only decreases the release of solid waste, but also moderates the greenhouse effect resulted from CO2. PMID:26549755

  9. Development of sintering-resistant CaO-based sorbent derived from eggshells and bauxite tailings for cyclic CO2 capture.

    PubMed

    Shan, ShaoYun; Ma, AiHua; Hu, YiCheng; Jia, QingMing; Wang, YaMing; Peng, JinHui

    2016-01-01

    Carbon dioxide, one of the major greenhouse gases, are believed to be a major contributor to global warming. As a consequence, it is imperative for us to control and remove CO2 emissions. The CaO, a kind of effective CO2 sorbent at high temperature, has attracted increasing attention due to some potential advantages. The main drawback in practical application is the deterioration of CO2 capture capacity following multiples cycles. In the present study, novel low-cost porous CaO-based sorbents with excellent CO2 absorption-desorption performance were synthesized using bauxite tailings (BTs) and eggshells as raw materials via solid-phase method. Effect of different BTs content on CO2 absorption-desorption properties was investigated. Phase composition and morphologies were analyzed by XRD and SEM, and CO2 absorption properties were investigated by the simultaneous thermogravimetric analyzer. The as-prepared CaO-based sorbent doped with 10 wt% BTs showed superior CO2 absorption stability during multiple absorption-desorption cycles, with being >55% conversion after 40 cycles. This improved CO2 absorption performance was attributed to the particular morphologies of the CaO-based sorbents. Additionally, during absorption-desorption cycles the occurrence of Ca12Al14O33 phase is considered to be responsible for the excellent CO2 absorption performance of CaO-based sorbents. In the meanwhile, the use of solid waste eggshell and BTs not only decreases the release of solid waste, but also moderates the greenhouse effect resulted from CO2.

  10. Prediction of estrus cyclicity in Asian elephants (Elephas maximus) through estimation of fecal progesterone metabolite: development of an enzyme-linked immuno-sorbent assay.

    PubMed

    Ghosal, R; Sukumar, R; Seshagiri, P B

    2010-05-01

    Asian elephants (Elephas maximus), prominent "flagship species", are listed under the category of endangered species (EN - A2c, ver. 3.1; IUCN Red List 2009) and there is a need for their conservation. This requires understanding demographic and reproductive dynamics of the species. Monitoring reproductive status of any species is traditionally being carried out through invasive blood sampling and this is restrictive for large animals such as wild or semi-captive elephants due to legal, ethical, and practical reasons. Hence, there is a need for a non-invasive technique to assess reproductive cyclicity profiles of elephants, which will help in the species' conservation strategies. In this study, we developed an indirect competitive enzyme linked immuno-sorbent assay (ELISA) to estimate the concentration of one of the progesterone-metabolites i.e., allopregnanolone (5 alpha-P-3OH) in fecal samples of Asian elephants. We validated the assay which had a sensitivity of 0.25 microM at 90% binding with an EC(50) value of 1.37 microM. Using female elephants, kept under semi-captive conditions in the forest camps of Mudumalai Wildlife Sanctuary, Tamil Nadu and Bandipur National Park, Karnataka, India, we measured fecal progesterone-metabolite (5 alpha-P-3OH) concentrations in six animals and showed their clear correlation with those of serum progesterone, measured by a standard radio-immuno assay. Statistical analyses using a Linear Mixed Effect model showed a positive correlation (P<0.1) between the profiles of fecal 5 alpha-P-3OH (range: 0.5-10 microg/g) and serum progesterone (range: 0.1-1.8 ng/mL). Therefore, our studies show, for the first time, that the fecal progesterone-metabolite assay could be exploited to predict estrus cyclicity and to potentially assess the reproductive status of captive and free-ranging female Asian elephants, thereby helping to plan their breeding strategy.

  11. Application of a new sorbent for combined SO{sub 2} and NO{sub x} removal. Final report

    SciTech Connect

    Nelson, S.G.

    1989-09-01

    The overall objective of this project was to further develop the application of a new class of dry, granular, SO{sub 2}/NO{sub x}-sorbent materials to bring them closer towards commercial usage in utility and industrial air-pollution control systems. The new sorbents are composite materials consisting of magnesium oxide (MgO) or calcium oxide (CaO) bonded to and reacted with vermiculite, a low-cost expanded silicate carrier. The sorbents possess some very unique and desirable properties. These properties include a higher-than-normal affinity for sulfur and nitrogen oxides in stack gases, excellent SO{sub 2}-removal efficiencies and attractive utilization rates at common stack gas temperatures, and the ability to be regenerated. The materials typically remove 99 percent of the SO{sub 2} and a significant percentage of the NO{sub x} in flue gases with high sorbent utilizations. Specific objectives of the project were to evaluate the performance of different continuous methods of employing the new sorbent materials in removing SO{sub 2} and NO{sub x} from a power plant flue gas, to examine the regeneration of one particularly promising sorbent composition: 45 wt % MgO-55 wt % Vermiculite, and to develop a sorption-regeneration system and cost estimates based on this material. The objectives were met in the project. The cost of the 15-month project was $229,717, of which OCDO provided $149,972 and Sanitech provided the remainder. In additions Sanitech and Ohio Edison made significant in-kind contributions to the project, in the form of existing facilities and equipment. The results of this project should help move the new technology forward toward commercialization. Required now are scale-ups of the new technology at more meaningful sizes.

  12. Extraction of trace nitrophenols in environmental water samples using boronate affinity sorbent.

    PubMed

    Zhang, Yong; Mei, Meng; Huang, Xiaojia; Yuan, Dongxing

    2015-10-29

    In this research, the applicability of a new sorbent based on boronate affinity material is demonstrated. For this purpose, six strong polar nitrophenols were selected as models which are difficult to be extracted in neutral form (only based on hydrophobic interactions). The extracted nitrophenols were separated and determined by high-performance liquid chromatography with diode array detection. The sorbent was synthesized by in situ copolymerization of 3-acrylamidophenylboronic acid and divinylbenzene using dimethyl sulfoxide and azobisisobutyronitrile as porogen solvent and initiator, respectively. The effect of the preparation parameters in the polymerization mixture on extraction performance was investigated in detail. The size and morphology of the sorbent have been characterized via different techniques such as infrared spectroscopy, elemental analysis, scanning electron microscopy and mercury intrusion porosimetry. The important parameters influencing the extraction efficiency were studied and optimized thoroughly. Under the optimum extraction conditions, the limits of detection (S/N = 3) and limits of quantification (S/N = 10) for the target nitrophenols were 0.097-0.28 and 0.32-0.92 μg/L, respectively. The precision of the proposed method was evaluated in terms of intra- and inter-assay variability calculated as RSD, and it was found that the RSDs were all below 9%. Finally, the developed method was successfully applied for environmental water samples such as wastewater, tap, lake and river water. The recoveries varied within the range of 71.2-115% with RSD below 11% in all cases. The results well demonstrate that the new boronate affinity sorbent can extract nitrophenols effectively through multi-interactions including boron-nitrogen coordination, hydrogen-bond and hydrophobic interactions between sorbent and analytes. PMID:26547495

  13. New ZnO-Based Regenerable Sulfur Sorbents for Fluid-Bed/Transport Reactor Applications

    SciTech Connect

    Slimane, R.B.; Lau, F.S.; Abbasian, J.; Ho, K.H.

    2002-09-19

    The overall objective of the ongoing sorbent development work at GTI is the advancement to the demonstration stage of a promising ZnO-TiO2 sulfur sorbent that has been developed under DCCA/ICCI and DOE/NETL sponsorship. This regenerable sorbent has been shown to possess an exceptional combination of excellent chemical reactivity, high effective capacity for sulfur absorption, high resistance to attrition, and regenerability at temperatures lower than required by typical zinc titanates.

  14. Novel Sorbent to Clean Up Biogas for CHPs

    SciTech Connect

    Alptekin, Gökhan O.; Jayataman, Ambalavanan; Schaefer, Matthew; Ware, Michael; Hunt, Jennifer; Dobek, Frank

    2015-05-30

    In this project, TDA Research Inc. (TDA) has developed low-cost (on a per unit volume of gas processed basis), high-capacity expendable sorbents that can remove both the H2S and organic sulfur species in biogas to the ppb levels. The proposed sorbents will operate downstream of a bulk desulfurization system as a polishing bed to provide an essentially sulfur-free gas to a fuel cell (or any other application that needs a completely sulfur-free feed). Our sorbents use a highly dispersed mixed metal oxides active phase with desired modifiers prepared over on a mesoporous support. The support structure allows the large organic sulfur compounds (such as the diethyl sulfide and dipropyl sulfide phases with a large kinetic diameter) to enter the sorbent pores so that they can be adsorbed and removed from the gas stream.

  15. Key factor in rice husk Ash/CaO sorbent for high flue gas desulfurization activity.

    PubMed

    Dahlan, Irvan; Lee, Keat Teong; Kamaruddin, Azlina Harun; Mohamed, Abdul Rahman

    2006-10-01

    Siliceous materials such as rice husk ash (RHA) have potential to be utilized as high performance sorbents for the flue gas desulfurization process in small-scale industrial boilers. This study presents findings on identifying the key factorfor high desulfurization activity in sorbents prepared from RHA. Initially, a systematic approach using central composite rotatable design was used to develop a mathematical model that correlates the sorbent preparation variables to the desulfurization activity of the sorbent. The sorbent preparation variables studied are hydration period, x1 (6-16 h), amount of RHA, x2 (5-15 g), amount of CaO, x3 (2-6 g), amount of water, x4 (90-110 mL), and hydration temperature, x5 (150-250 degrees C). The mathematical model developed was subjected to statistical tests and the model is adequate for predicting the SO2 desulfurization activity of the sorbent within the range of the sorbent preparation variables studied. Based on the model, the amount of RHA, amount of CaO, and hydration period used in the preparation step significantly influenced the desulfurization activity of the sorbent. The ratio of RHA and CaO used in the preparation mixture was also a significant factor that influenced the desulfurization activity of the sorbent. A RHA to CaO ratio of 2.5 leads to the formation of specific reactive species in the sorbent that are believed to be the key factor responsible for high desulfurization activity in the sorbent. Other physical properties of the sorbent such as pore size distribution and surface morphology were found to have insignificant influence on the desulfurization activity of the sorbent.

  16. Evaluation of magnetic nanoparticles to serve as solid-phase extraction sorbents for the determination of endocrine disruptors in milk samples by gas chromatography mass spectrometry.

    PubMed

    Synaridou, Maria-Evangelia S; Sakkas, Vasilios A; Stalikas, Constantine D; Albanis, Triantafyllos A

    2014-06-27

    A rapid magnetic solid-phase extraction (MSPE) is proposed based on C18-functionalized magnetic silica nanoparticles as sorbents, for the determination of endocrine disruptors - 20 organochlorine pesticides and 6 polychlorinated biphenyls - in milk samples. Magnetic nanoparticles are characterized by several techniques, such as Scanning Electron Microscopy, X-Ray diffraction, Brunauer-Emmett-Teller and Fourier transform-infrared. The MSPE is performed by dispersion of the Fe3O4@SiO2@C18 nanoparticles in milk samples with sonication, after protein precipitation. Then, the sorbent is collected by applying an external magnetic field and the analytes are desorbed by n-hexane. Several parameters affecting the extraction efficiency of target analytes by the magnetic nanoparticles are investigated, including washing and elution solvents, amount of sorbents, time of extraction and elution, sample and elution solvent volume. The proposed method is optimized by means of experimental design and response surface methodology. When coupled with gas chromatography-mass spectrometry detection and under optimum extraction conditions, average recoveries of target analytes are found to be in the range of 79% to 116%. The proposed MSPE-GC-MS analytical method has a linear calibration curve for all target analytes with coefficients of determination to range from 0.9950 to 0.9999. The limits of quantification are found to be between 0.2 and 1μg/L ensuring compliance with the maximum residue limits established by European Commission and Codex Alimentarius, for OCPs and PCBs residues in milk. The proposed method is applied to the determination of target analytes in milk samples from local markets.

  17. DEVELOPMENT OF AN IMPROVED TITANATE-BASED SORBENT FOR STRONTIUM AND ACTINIDE SEPARATIONS UNDER STRONGLY ALKALINE CONDITIONS

    SciTech Connect

    Hobbs, D.; Peters, T.; Taylor-Pashow, K.; Fink, S.

    2010-02-18

    High-level nuclear waste produced from fuel reprocessing operations at the Savannah River Site (SRS) requires pretreatment to remove {sup 134,137}Cs, {sup 90}Sr, and alpha-emitting radionuclides (i.e., actinides) prior to disposal onsite as low level waste. Separation processes at SRS include the sorption of {sup 90}Sr and alpha-emitting radionuclides onto monosodium titanate (MST) and caustic side solvent extraction of {sup 137}Cs. The MST and separated {sup 137}Cs is encapsulated along with the sludge fraction of high-level waste (HLW) into a borosilicate glass waste form for eventual entombment at a federal repository. The predominant alpha-emitting radionuclides in the highly alkaline waste solutions include plutonium isotopes {sup 238}Pu, {sup 239}Pu, and {sup 240}Pu; {sup 237}Np; and uranium isotopes, {sup 235}U and {sup 238}U. This paper describes recent results evaluating the performance of an improved sodium titanate material that exhibits increased removal kinetics and capacity for {sup 90}Sr and alpha-emitting radionuclides compared to the current baseline material, MST.

  18. High capacity immobilized amine sorbents

    DOEpatents

    Gray, McMahan L.; Champagne, Kenneth J.; Soong, Yee; Filburn, Thomas

    2007-10-30

    A method is provided for making low-cost CO.sub.2 sorbents that can be used in large-scale gas-solid processes. The improved method entails treating an amine to increase the number of secondary amine groups and impregnating the amine in a porous solid support. The method increases the CO.sub.2 capture capacity and decreases the cost of utilizing an amine-enriched solid sorbent in CO.sub.2 capture systems.

  19. Development of a standard gas generating vial comprised of a silicon oil-polystyrene/divinylbenzene composite sorbent.

    PubMed

    Grandy, Jonathan J; Gómez-Ríos, German A; Pawliszyn, Janusz

    2015-09-01

    In this work, a highly reproducible standard gas generating vial is proposed. The vial is comprised of a silicon diffusion pump oil spiked with an appropriate calibration compound, such as modified McReynolds probes (benzene, 2-pentanone, pyridine, 1-nitropropane, 1-pentanol, and n-octane), and then mixed with polystyrene/divinylbenzene (PS/DVB) particles. The concentrations of these compounds in gaseous headspace were found to substantially decrease in comparison to previously developed hydrocarbon pump oil based vials; hence, the amount of standard loaded onto SPME fibers was at most, half that of the previous vial design. Depletion for all compounds after 208 successive extractions was shown to be less than 3.5%. Smaller quantities of standards being used resulted in a vial that depleted slower while remaining statistically repeatable over a wider number of runs. Indeed, it was found that depletion could be largely predicted by using a mass balance theoretical model. This behavior allowed a further increase in the number of loadings that could be performed repeatedly. At a 95% level of confidence, the ANOVA test demonstrated that the prepared vials were statistically identical, with no significant intra- or inter-batch differences. In addition, it was found that vials stored under different conditions (e.g. under light exposure, room temperature, and within a refrigerator) were stable over 10 weeks. Silicon based vials proved to be ideal for performing instrument quality control and loading of internal standards onto fibers, both of which are of great importance when performing on-site analysis using portable GC-MS instrumentation and high throughput determinations in laboratory. PMID:26243704

  20. Development of a standard gas generating vial comprised of a silicon oil-polystyrene/divinylbenzene composite sorbent.

    PubMed

    Grandy, Jonathan J; Gómez-Ríos, German A; Pawliszyn, Janusz

    2015-09-01

    In this work, a highly reproducible standard gas generating vial is proposed. The vial is comprised of a silicon diffusion pump oil spiked with an appropriate calibration compound, such as modified McReynolds probes (benzene, 2-pentanone, pyridine, 1-nitropropane, 1-pentanol, and n-octane), and then mixed with polystyrene/divinylbenzene (PS/DVB) particles. The concentrations of these compounds in gaseous headspace were found to substantially decrease in comparison to previously developed hydrocarbon pump oil based vials; hence, the amount of standard loaded onto SPME fibers was at most, half that of the previous vial design. Depletion for all compounds after 208 successive extractions was shown to be less than 3.5%. Smaller quantities of standards being used resulted in a vial that depleted slower while remaining statistically repeatable over a wider number of runs. Indeed, it was found that depletion could be largely predicted by using a mass balance theoretical model. This behavior allowed a further increase in the number of loadings that could be performed repeatedly. At a 95% level of confidence, the ANOVA test demonstrated that the prepared vials were statistically identical, with no significant intra- or inter-batch differences. In addition, it was found that vials stored under different conditions (e.g. under light exposure, room temperature, and within a refrigerator) were stable over 10 weeks. Silicon based vials proved to be ideal for performing instrument quality control and loading of internal standards onto fibers, both of which are of great importance when performing on-site analysis using portable GC-MS instrumentation and high throughput determinations in laboratory.

  1. SORBENT DEVELOPMENT FOR MERCURY CONTROL. Final topical report including semiannual for January 1, 1998 through June 30, 1998.

    SciTech Connect

    David J. Hassett; Edwin S. Olson; Grant E. Dunham; Ramesh K. Sharma; Ronald C. Timpe; Stanley J. Miller

    1998-10-01

    The US Environmental Protection Agency (EPA) draft Mercury Study Report to Congress (1) estimated anthropogenic mercury emissions to be 253 tons/yr in the US, with the majority (216 tons/yr) from combustion sources. The three main combustion sources listed were coal (72 tons/yr), medical waste incinerators (65 tons/yr), and municipal waste combustors (64 tons/yr). The emissions from both medical waste incinerators and municipal waste combustors were recently regulated, which, together with the reduction of mercury in consumer products such as batteries and fluorescent lights, has already reduced the emissions from these sources, as stated in the final EPA Mercury Report to Congress (2). EPA now estimates total point-source mercury emissions to be 158 tons/yr, with coal remaining at 72 tons/yr, while medical waste incinerators are down to 16 tons/yr and municipal waste combustors are at 30 tons/yr. Coal is now the primary source of anthropogenic mercury emissions in the US, accounting for 46%. In addition, the use of coal in the US has been increasing every year and passed the 1-billion-ton-per-year mark for the first time in 1997 (3). At the current rate of increase, coal consumption would reach 1.4 billion tons annually by the year 2020. On a worldwide basis, the projected increase in coal usage over the next two decades in China, India, and Indonesia will dwarf the current US coal consumption level. Therefore, in the US coal will be the dominant source of mercury emissions and worldwide coal may be the cause of significantly increased mercury emissions unless an effective control strategy is implemented. However, much uncertainty remains over the most technically sound and cost-effective approach for reducing mercury emissions from coal-fired boilers, and a number of critical research needs will have to be met to develop better control (2).

  2. FURNACE INJECTION OF ALKALINE SORBENTS FOR SULFURIC ACID REMOVAL

    SciTech Connect

    Gary M. Blythe

    2004-01-01

    different boilers, and to determine balance-of-plant impacts. The first long-term test was conducted on FirstEnergy's BMP Unit 3, and the second was conducted on AEP's Gavin Plant, Unit 1. The Gavin Plant test provided an opportunity to evaluate the effects of sorbent injected into the furnace on SO{sub 3} formed across an operating SCR reactor. A final task in the project was to compare projected costs for furnace injection of magnesium hydroxide slurries to estimated costs for other potential sulfuric acid control technologies. Estimates were developed for reagent and utility costs, and capital costs, for furnace injection of magnesium hydroxide slurries and seven other sulfuric acid control technologies. The estimates were based on retrofit application to a model coal-fired plant.

  3. Hot gas desulfurization with sorbents containing mixed metal oxides

    SciTech Connect

    Akyurtlu, J.F.; Akyurtlu, A.

    1992-12-31

    Advanced power generation systems such as the integrated gasification combined cycle power generators and the molten carbonate fuel cells have stringent fuel gas desulfurization requirements and process economics dictates that this desulfurization be performed near the temperature of the gasification off-gas. The most advanced hot gas desulfurization technology today is based on the zinc ferrite sorbent which has several shortcomings such as zinc loss by evaporation, and incomplete regeneration due to sulfate formation. The objective of this study is to develop an improved sorbent which can reduce H{sub 2}S levels to 1 ppmv or less, which can stabilize zinc, and produce economically recoverable amounts of elemental sulfur during regeneration. For this purpose, the desulfurization performance.of sorbents prepared by the addition of various amounts of V{sub 2}0{sub 5} to the zinc ferrite sorbent is investigated. Preliminary experiments show that the sorbent containing about 4.8 mass % vanadium shows a superior desulfurization performance compared to zinc ferrite. Addition of vanadium suppresses residual sulfate formation and possibly zinc evaporation. significant quantities of elemental sulfur were observed after the regeneration of vanadium containing sorbents.

  4. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    SciTech Connect

    David A. Green; Brian S. Turk; Jeffrey W. Portzer; Raghubir P. Gupta; William J. McMichael; Ya Liang; Douglas P. Harrison

    2003-01-01

    The objective of this project is to develop a simple and inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable sorbent. The sorbents being investigated in this project are primarily alkali carbonates, and particularly sodium carbonate and potassium carbonate, which are converted to bicarbonates or intermediate salts through reaction with carbon dioxide and water vapor. Bicarbonates are regenerated to carbonates when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. This quarter, electrobalance tests suggested that high calcination temperatures decrease the activity of sodium bicarbonate Grade 1 (SBC No.1) during subsequent carbonation cycles, but there is little or no progressive decrease in activity in successive cycles. SBC No.1 appears to be more active than SBC No.3. As expected, the presence of SO{sub 2} in simulated flue gas results in a progressive loss of sorbent capacity with increasing cycles. This is most likely due to an irreversible reaction to produce Na{sub 2}SO{sub 3}. This compound appears to be stable at calcination temperatures as high as 200 C. Tests of 40% supported potassium carbonate sorbent and plain support material suggest that some of the activity observed in tests of the supported sorbent may be due to adsorption by the support material rather than to carbonation of the sorbent.

  5. Adsorption of Ammonia on Regenerable Carbon Sorbents

    NASA Technical Reports Server (NTRS)

    Wójtowicz, Marek A.; Cosgrove, Jesph E.; Serio, Michael A..; Wilburn, Monique

    2015-01-01

    Results are presented on the development of reversible sorbents for the combined carbon dioxide, moisture, and trace-contaminant (TC) removal for use in Extravehicular Activities (EVAs), and more specifically in the Primary Life Support System (PLSS). The currently available life support systems use separate units for carbon dioxide, trace contaminants, and moisture control, and the long-term objective is to replace the above three modules with a single one. Data on sorption and desorption of ammonia, which is a major TC of concern, are presented in this paper. The current TC-control technology involves the use of a packed bed of acid-impregnated granular charcoal, which is non-regenerable, and the carbon-based sorbent under development in this project can be regenerated by exposure to vacuum at room temperature. In this study, several carbon sorbents were fabricated and tested for ammonia sorption. Ammonia-sorption capacity was related to carbon pore structure characteristics, and the temperature of oxidative carbon-surface treatment was optimized for enhanced ammonia-sorption performance.

  6. Investigation of mixed metal sorbent/catalysts for the simultaneous removal of sulfur and nitrogen oxides. Semiannual report, Apr 1, 1998--Oct 31, 1998

    SciTech Connect

    Dr. Ates Akyurtlu; Dr. Jale F. Akyurtlu

    1998-10-31

    Simultaneous removal of SO{sub 2} and NO{sub x} using a regenerable solid sorbent will constitute an important improvement over the use of separate processes for the removal of these two pollutants from stack gases and possibly eliminate several shortcomings of the individual SO{sub 2} and NO{sub x} removal operations. The work done at PETC and the DOE-funded investigation of the investigators on the sulfation and regeneration of alumina-supported cerium oxide sorbents have shown that they can perform well at relatively high temperatures (823--900 K) as regenerable desulfurization sorbents. Survey of the recent literature shows that addition of copper oxide to ceria lowers the sulfation temperature of ceria down to 773 K, sulfated ceria-based sorbents can function as selective SCR catalysts even at elevated temperatures, SO{sub 2} can be directly reduced to sulfur by CO on CuO-ceria catalysts, and ceria-based catalysts may have a potential for selective catalytic reduction of NO{sub x} by methane. These observations indicate a possibility of developing a ceria-based sorbent/catalyst which can remove both SO{sub 2} and NO{sub x} from flue gases within a relatively wide temperature window, produce significant amounts of elemental sulfur during regeneration, and use methane for the selective catalytic reduction of NO{sub x}. The objective of this research is to conduct kinetic and parametric studies of the selective catalytic reduction of NO{sub x} with NH{sub 3} and CH{sub 4} over alumina-supported cerium oxide and copper oxide-cerium oxide sorbent/catalysts; investigate SO{sub 2} removal at lower temperatures by supported copper oxide-cerium oxide sorbents; and investigate the possibility of elemental sulfur production during regeneration with CO or with CH{sub 4} air mixtures. The sorbents consisting of cerium oxide and copper oxide impregnated on alumina have been prepared and characterized. Their sulfation performance has been investigated in a TGA setup

  7. Advanced in-duct sorbent injection for SO{sub 2} control. Final technical report

    SciTech Connect

    Stouffer, M.R.; Withium, J.A.; Rosenhoover, W.A.; Maskew, J.T.

    1994-12-01

    The objective of this research project was to develop a second generation duct sorbent injection technology as a cost-effective compliance option for the 1990 Clean Air Act Amendments. Research and development work was focused on the Advanced Coolside process, which showed the potential for exceeding the original performance targets of 90% SO{sub 2} removal and 60% sorbent utilization. Process development was conducted in a 1000 acfm pilot plant. The pilot plant testing showed that the Advanced Coolside process can achieve 90% SO{sub 2} removal at sorbent utilizations up to 75%. The testing also showed that the process has the potential to achieve very high removal efficiency (90 to >99%). By conducting conceptual process design and economic evaluations periodically during the project, development work was focused on process design improvements which substantially lowered process capital and operating costs, A final process economic study projects capital costs less than one half of those for limestone forced oxidation wet FGD. Projected total SO{sub 2} control cost is about 25% lower than wet FGD for a 260 MWe plant burning a 2.5% sulfur coal. A waste management study showed the acceptability of landfill disposal; it also identified a potential avenue for by-product utilization which should be further investigated. Based on the pilot plant performance and on the above economic projections, future work to scale up the Advanced Coolside process is recommended.

  8. Fenceline Measurements of Speciated VOCs Using Passive Sorbent Tubes Deployed Around Oil and Natural Gas Production Pads in Colorado and Texas

    EPA Science Inventory

    A U.S. EPA team, consisting of the Office of Research and Development and Region 6 (Dallas) and Region 8 (Denver), deployed passive-diffusive sorbent tubes as part of a method evaluation study around one oil and natural gas production pad in both the Barnett Shale Basin in Texas ...

  9. Investigation of combined S02/N0x Removal by Ceria Sorbents

    SciTech Connect

    Ates Akyurtlu; Jale F. Akyurtlu

    1996-11-01

    This final report describes the work done under the sponsorship of the U.S. DOE for the support of advanced fossil resource utilization research at historically black colleges and universities, Grant No. DE-Ps22-92MT920 on "Investigation of Combined S02/NOx Removal by Ceria Sorbents". The work was conducted at the Department of Chemical Engineering of Hampton University. The industrial partner was Malcolm Pirnie,Inc. Environmental Engineers, Scientists and Planners, who handled the metal analysis and XRD measurements on the solid sorbents; they have also supplied the flyash used in the experimental program. The development of a commercial process concept, economic analysis, and evaluation of process alternatives were undertaken by TECOGEN of Waltham, MA.

  10. Advanced sulfur control concepts in hot-gas desulfurization technology: Phase 1, Feasibility of the direct production of elemental sulfur during the regeneration of high temperature desulfurization sorbents

    SciTech Connect

    Lopez, A.; White, J.; Groves, F.R.; Harrison, D.P.

    1994-10-01

    This topical report de-scribes the results of Phase 1 research performed during the first six months of a three-year contract to study the feasibility of the direct production of elemental sulfur during the regeneration of high temperature desulfurization sorbents. Much effort has gone into the development of a high-temperature meal oxide sorbent process for removal of H{sub 2}S from the coal gas. A number of sorbents based upon metals such as zinc, iron, manganese and others have been studied. In order for high temperature desulfurization to be economical it is necessary that the sorbents be regenerated to permit multicycle operation. Current methods of sorbent regeneration involve oxidation of the metal sulfide to reform the metal oxide and free the sulfur as SO{sub 2}. An alternate regeneration process in which the sulfur is liberated in elemental form is preferable. The overall objective of the current research is to study simpler and economically superior processing of known sorbents capable of producing elemental sulfur during regeneration. This topical report summarizes the first steps of this effort. A literature search has been completed to identify possible regeneration concepts and to collect relevant thermodynamic, kinetic, and process data. Three concepts involving reaction with SO{sub 2}, partial oxidation using an O{sub 2} {minus} H{sub 2}O mixture, and steam regeneration have been identified. The first two concepts result in the direct production of elemental sulfur while H{sub 2}S is the product of steam regeneration. This concept is of potential interest, however, since existing Claus technology can be used to convert H{sub 2}S to elemental sulfur. Following the literature search, a thermodynamic analysis, based upon free-energy minimization was carried out to evaluate candidate sorbents for possible use with the three regeneration concepts.

  11. Supported-sorbent injection. Final report

    SciTech Connect

    Nelson, S. Jr.

    1997-07-01

    A new retrofitable, wastefree acid-rain control concept was pilot-tested at Ohio Edison`s high-sulfur coal-fired R.E. Burger generating station at the 2-MWe level. During the project, moistened {open_quotes}supported{close_quotes} sorbents, made from a combination of lime and vermiculite or perlite, were injected into a humidified 6,500-acfm flue-gas slipstream. After the sorbents reacted with the sulfur dioxide in the flue gas, they were removed from ductwork with a cyclone and baghouse. The $1.0 million project was co-funded by Sorbent Technologies Corporation, the Ohio Edison Company, and the Ohio Coal Development Office. The project included a preliminary bench-scale testing phase, construction of the pilot plant, parametric studies, numerous series of recycle tests, and a long-term run. The project proceeded as anticipated and achieved its expected results. This duct injection technology successfully demonstrated SO{sub 2}-removal rates of 80 to 90% using reasonable stoichiometric injection ratios (2:1 Ca:S) and approach temperatures (20-25F). Under similar conditions, dry injection of hydrated lime alone typically only achieves 40 to 50% SO{sub 2} removal. During the testing, no difficulties were encountered with deposits in the ductwork or with particulate control, which have been problems in tests of other duct-injection schemes.

  12. Use of biomass sorbents for oil removal from gas station runoff.

    PubMed

    Khan, Eakalak; Virojnagud, Wanpen; Ratpukdi, Thunyalux

    2004-11-01

    The use of biomass sorbents, which are less expensive and more biodegradable than synthetic sorbents, for oil removal from gas station runoff was investigated. A bench-scale flume experiment was conducted to evaluate the oil removal and retention capabilities of the biomass sorbents which included kapok fiber, cattail fiber, Salvinia sp., wood chip, rice husk, coconut husk, and bagasse. Polyester fiber, a commercial synthetic sorbent, was also experimented for comparison purpose. Oil sorption and desorption tests were performed at a water flow rate of 20 lmin-1. In the oil sorption tests, a 50 mgl(-1) of used engine oil-water mixture was synthesized to simulate the gas station runoff. The mass of oil sorbed for all sorbents, except coconut husk and bagasse, was greater than 70%. Cattail fiber and polyester fiber were the sorbents that provided the least average effluent oil concentrations. Oil selectivity (hydrophobic properties) and physical characteristics of the sorbents are the two main factors that influence the oil sorption capability. The used sorbents from the sorption tests were employed in the desorption tests. Results indicated that oil leached out of all the sorbents tested. Polyester fiber released the highest amount of oil, approximately 4% (mass basis) of the oil sorbed.

  13. Use of biomass sorbents for oil removal from gas station runoff.

    PubMed

    Khan, Eakalak; Virojnagud, Wanpen; Ratpukdi, Thunyalux

    2004-11-01

    The use of biomass sorbents, which are less expensive and more biodegradable than synthetic sorbents, for oil removal from gas station runoff was investigated. A bench-scale flume experiment was conducted to evaluate the oil removal and retention capabilities of the biomass sorbents which included kapok fiber, cattail fiber, Salvinia sp., wood chip, rice husk, coconut husk, and bagasse. Polyester fiber, a commercial synthetic sorbent, was also experimented for comparison purpose. Oil sorption and desorption tests were performed at a water flow rate of 20 lmin-1. In the oil sorption tests, a 50 mgl(-1) of used engine oil-water mixture was synthesized to simulate the gas station runoff. The mass of oil sorbed for all sorbents, except coconut husk and bagasse, was greater than 70%. Cattail fiber and polyester fiber were the sorbents that provided the least average effluent oil concentrations. Oil selectivity (hydrophobic properties) and physical characteristics of the sorbents are the two main factors that influence the oil sorption capability. The used sorbents from the sorption tests were employed in the desorption tests. Results indicated that oil leached out of all the sorbents tested. Polyester fiber released the highest amount of oil, approximately 4% (mass basis) of the oil sorbed. PMID:15488931

  14. Mercury removal from flue gases by novel regenerable magnetic nanocomposite sorbents

    SciTech Connect

    Jie Dong; Zhenghe Xu; Steven M. Kuznicki

    2009-05-01

    Magnetic zeolite composites with supported silver nanoparticles are a new class of multifunctional materials with potential applications as recyclable catalysts, disinfectants, and sorbents. This study evaluated the suitability of the magnetic composites as sorbents for the removal of elemental mercury vapor from flue gases of coal-fired power plants. The sorbents were found to completely capture mercury at temperatures up to 200{sup o}C, and the mercury capacity of the sorbents was found to be affected by the state, content, and size of the silver particles in the composite. Cumulative or extended thermal treatments at 400{sup o}C were found to improve the mercury capture capacity, allowing the sorbent to be regenerated and recycled multiple times without performance degradation. The magnetic sorbent was readily separated from fly ash by magnetic separation, leaving the fly ash essentially free of sorbent contamination. In initial in-plant tests, the sorbents were able to capture mercury from the flue gases of an operational, full-scale, coal-fired power plant. The combination of mercury capacity, ease of separation and regeneration, and recyclability makes these multifunctional magnetic composites excellent candidate sorbents for the control of mercury emissions from coal-fired power plants. 35 refs., 5 figs., 2 tabs.

  15. Iron blast furnace slag/hydrated lime sorbents for flue gas desulfurization.

    PubMed

    Liu, Chiung-Fang; Shih, Shin-Min

    2004-08-15

    Sorbents prepared from iron blast furnace slag (BFS) and hydrated lime (HL) through the hydration process have been studied with the aim to evaluate their reactivities toward SO2 under the conditions prevailing in dry or semidry flue gas desulfurization processes. The BFS/HL sorbents, having large surface areas and pore volumes due to the formation of products of hydration, were highly reactive toward SO2, as compared with hydrated lime alone (0.24 in Ca utilization). The sorbent reactivity increased as the slurrying temperature and time increased and as the particle size of BFS decreased; the effects of the liquid/solid ratio and the sorbent drying conditions were negligible. The structural properties and the reactivity of sorbent were markedly affected by the BFS/HL ratio; the sorbent with 30/70 ratio had the highest 1 h utilization of Ca, 0.70, and SO2 capture, 0.45 g SO2/g sorbent. The reactivity of a sorbent was related to its initial specific surface area (Sg0) and molar content of Ca (M(-1)); the 1 h utilization of Ca increased almost linearly with increasing Sg0/M. The results of this study are useful to the preparation of BFS/HL sorbents with high reactivity for use in the dry and semidry processes to remove SO2 from the flue gas.

  16. Iron blast furnace slag/hydrated lime sorbents for flue gas desulfurization.

    PubMed

    Liu, Chiung-Fang; Shih, Shin-Min

    2004-08-15

    Sorbents prepared from iron blast furnace slag (BFS) and hydrated lime (HL) through the hydration process have been studied with the aim to evaluate their reactivities toward SO2 under the conditions prevailing in dry or semidry flue gas desulfurization processes. The BFS/HL sorbents, having large surface areas and pore volumes due to the formation of products of hydration, were highly reactive toward SO2, as compared with hydrated lime alone (0.24 in Ca utilization). The sorbent reactivity increased as the slurrying temperature and time increased and as the particle size of BFS decreased; the effects of the liquid/solid ratio and the sorbent drying conditions were negligible. The structural properties and the reactivity of sorbent were markedly affected by the BFS/HL ratio; the sorbent with 30/70 ratio had the highest 1 h utilization of Ca, 0.70, and SO2 capture, 0.45 g SO2/g sorbent. The reactivity of a sorbent was related to its initial specific surface area (Sg0) and molar content of Ca (M(-1)); the 1 h utilization of Ca increased almost linearly with increasing Sg0/M. The results of this study are useful to the preparation of BFS/HL sorbents with high reactivity for use in the dry and semidry processes to remove SO2 from the flue gas. PMID:15382877

  17. ASSESSMENT OF LOW COST NOVEL SORBENTS FOR COAL-FIRED POWER PLANT MERCURY CONTROL

    SciTech Connect

    Sharon Sjostrom

    2004-03-01

    The injection of sorbents upstream of a particulate control device is one of the most promising methods for controlling mercury emissions from coal-fired utility boilers with electrostatic precipitators and fabric filters. Studies carried out at the bench-, pilot-, and full-scale have shown that a wide variety of factors may influence sorbent mercury removal effectiveness. These factors include mercury species, flue gas composition, process conditions, existing pollution control equipment design, and sorbent characteristics. The objective of the program is to obtain the necessary information to assess the viability of lower cost alternatives to commercially available activated carbon for mercury control in coal-fired utilities. Prior to injection testing, a number of sorbents were tested in a slipstream fixed-bed device both in the laboratory and at two field sites. Based upon the performance of the sorbents in a fixed-bed device and the estimated cost of mercury control using each sorbent, seventeen sorbents were chosen for screening in a slipstream injection system at a site burning a Western bituminous coal/petcoke blend, five were chosen for screening at a site burning a subbituminous Powder River Basin (PRB) coal, and nineteen sorbents were evaluated at a third site burning a PRB coal. Sorbents evaluated during the program were of various materials, including: activated carbons, treated carbons, other non-activated carbons, and non-carbon material. The economics and performance of the novel sorbents evaluated demonstrate that there are alternatives to the commercial standard. Smaller enterprises may have the opportunity to provide lower price mercury sorbents to power generation customers under the right set of circumstances.

  18. Peat hybrid sorbents for treatment of wastewaters and remediation of polluted environment

    NASA Astrophysics Data System (ADS)

    Klavins, Maris; Burlakovs, Juris; Robalds, Artis; Ansone-Bertina, Linda

    2015-04-01

    For remediation of soils and purification of polluted waters, wastewaters, sorbents might be considered as an prospective group of materials and amongst them peat have a special role due to low cost, biodegradability, high number of functional groups, well developed surface area and combination of hydrophilic/hydrophobic structural elements. Peat as sorbent have good application potential for removal of trace metals, and we have demonstrated peat sorption capacities, sorption kinetics, thermodynamics in respect to metals with different valencies - Tl(I), Cu(II), Cr(III). However peat sorption capacity in respect to nonmetallic (anionic species) elements is low. Also peat mechanical properties do not support application in large scale column processes. To expand peat application possibilities the approach of biomass based hybrid sorbents has been elaborated. The concept "hybrid sorbent" in our understanding means natural, biomass based sorbent modified, covered with another sorbent material, thus combining two types of sorbent properties, sorbent functionalities, surface properties etc. As the "covering layer" both inorganic substances, mineral phases (iron oxohydroxides, oxyapatite) both organic polymers (using graft polymerization) were used. The obtained sorbents were characterised by their spectral properties, surface area, elemental composition. The obtained hybrid sorbents were tested for sorption of compounds in anionic speciation forms, for example of arsenic, antimony, tellurium and phosphorous compounds in comparison with weakly basic anionites. The highest sorption capacity was observed when peat sorbents modified with iron compounds were used. Sorption of different arsenic speciation forms onto iron-modified peat sorbents was investigated as a function of pH and temperature. It was established that sorption capacity increases with a rise in temperature, and the calculation of sorption process thermodynamic parameters indicates the spontaneity of sorption

  19. Catalytic regeneration of mercury sorbents.

    PubMed

    Bentley, Mark; Fan, Maohong; Dutcher, Bryce; Tang, Mingchen; Argyle, Morris D; Russell, Armistead G; Zhang, Yulong; Sharma, M P; Swapp, Susan M

    2013-11-15

    Traditionally, mercury sorbents are disposed of in landfills, which may lead to contamination of soil and groundwater. In this work, the regeneration of activated carbon (AC) as a mercury sorbent was investigated. The decomposition of HgCl2 on the surface of pure AC was studied, as well as sorbent which has been treated with FeCl3 or NaCl. In all cases, the sorbent is found to be structurally stable through a single regeneration, which is verified through BET, XRD, and XPS analysis. The desorption of mercury from the sorbent is found to follow Henry's law. Additionally, a kinetic analysis suggests that although the presence of activated carbon lowers the energy requirement for the desorption of mercury, it significantly decreases the rate by decreasing the concentration of the HgCl2. FeCl3 and NaCl both promoted the decomposition of HgCl2, but FeCl3 did so more significantly, increasing the rate constants by a factor of 10 and decreasing the activation energy for the decomposition of HgCl2 by 14% to 40%.

  20. [[Preparation of boronate affinity sorbent and its extraction performance for benzoylurea pesticides

    PubMed

    Zhang, Yong; Mei, Meng; Liu, Yi; Yu, Jie; Huang, Xiaojia; Yuan, Dongxing

    2014-09-01

    A new boronate affinity monolithic material was prepared and used as the extraction medium of stir cake sorptive extraction (SCSE). The porous boronate affinity sorbent was prepared by in situ copolymerization of 3-acrylamidophenylboronic acid (APB) and divinyl benzene (DVB). To achieve optimum extraction performance for benzoylurea pesticides, several parameters, including desorption solvent, pH value, ionic strength in sample matrix, extraction and desorption times, were investigated in detail. At the same time, a simple, sensitive and environment friendly method for the determination of benzoylurea pesticides in water and juice samples was developed by the combination of SCSE-APBDVB with HPLC equipped with a diode array detector. Under the optimized experimental conditions, the limits of detection (S/N = 3) for target analytes were 0.055-0.11 μg/L in water and 0.095-0.31 μg/L in juice. The precision of the proposed method was evaluated in terms of intra- and inter-assay repeatability calculated as RSD, and it was found that the RSDs were all below 9.0%. The developed method was successfully applied to the determination of benzoylurea pesticide residues in water and juice samples and satisfactory recoveries of spiked target compounds were in the range of 75.6%-109%. The results well demonstrate that the new sorbent can extract benzoylurea pesticides effectively through multi-interactions including boron-nitrogen coordination, hydrogen-bond and hydrophobic interactions between sorbent and analytes. PMID:25752092

  1. Composition modification of zinc titanate sorbents for hot gas desulfurization. Technical report, March 1--May 31, 1995

    SciTech Connect

    Swisher, J.H.

    1995-12-31

    For new coal gasification systems, zinc titanate sorbents are being developed to remove sulfur from the hot product gas prior to its use in combined cycle turbines and high temperature fuel cells. Although most of the properties of these sorbents are very attractive, there are still concerns about durability over many sulfidation-regeneration cycles and zinc losses due to vaporization. Doping the zinc titanate with other metal ions could alleviate both concerns, which are the objectives of this project. After a screening study was completed, it was decided that Cr offered more promise as a dopant than Ni, Cu, Mg, and Al. Therefore six new sorbent formulations containing Cr were prepared, and they are now being evaluated with a series of bulk density, X-ray diffraction, crush strength and thermogravimetric analysis (TGA) measurements. Results to date suggest that, while Zn vaporization losses can be reduced with Cr additions, a penalty in chemical reactivity occurs. A fixed bed test was also completed this quarter on a Cr-containing formulation. The H{sub 2}S breakthrough time was about 11 hours, and utilization of Zn in the sorbent was 60.5%.

  2. Performance of copper chloride-impregnated sorbents on mercury vapor control in an entrained-flow reactor system

    SciTech Connect

    Sang-Sup Lee; Joo-Youp Lee; Tim C. Keener

    2008-11-15

    An entrained-flow system has been designed and constructed to simulate in-flight mercury (Hg) capture by sorbent injection in ducts of coal-fired utility plants. The test conditions of 1.2-sec residence time, 140{degree}C gas temperature, 6.7 m/sec (22 ft/sec) gas velocity, and 0-0.24 g/m{sup 3} (0-15 lbs of sorbent per 1 million actual cubic feet of flue gas sorbent injection rates were chosen to simulate conditions in the ducts. Four kinds of sorbents were used in this study. Darco Hg-LH (lignite-based) served as a benchmark sorbent with which Hg control capability of other sorbents could be compared. Also, Darco-FGD (lignite-based) was used as a representative raw activated carbon sorbent. Two different copper chloride-impregnated sorbents were developed in the laboratory and tested in the entrained-flow system to examine the possibility of using these sorbents at coal-fired power plants. The test results showed that one of the copper chloride sorbents has remarkable elemental mercury (Hg{sup 0}) oxidation capability, and the other sorbent demonstrated a better performance in Hg removal than Darco Hg-LH. 13 refs., 4 figs., 3 tabs.

  3. Post-Combustion and Pre-Combustion CO2 Capture Solid Sorbents

    SciTech Connect

    Siriwardane, R.V.; Stevens, R.W.; Robinson, Clark

    2007-11-01

    Combustion of fossil fuels is one of the major sources of the greenhouse gas CO2. Pressure swing adsorption/sorption (PSA/PSS) and temperature swing adsorption/sorption (TSA/TSS) are some of the potential techniques that could be utilized for removal of CO2 from fuel gas streams. It is very important to develop sorbents to remove CO2 from fuel gas streams that are applicable for a wide range of temperatures. NETL researchers have developed novel CO2 capture sorbents for low, moderate, and high temperature applications. A novel liquid impregnated solid sorbent was developed for CO2 removal in the temperature range of ambient to 60 °C. The sorbent is regenerable at 60 – 80 °C. The sorbent formulations were prepared to be suitable for various reactor configurations (i.e., fixed and fluidized bed). Minimum fluidization gas velocities were also determined. Multi-cycle tests conducted in an atmospheric bench scale reactor with simulated flue gas indicated that the sorbent retains its CO2 sorption capacity with a CO2 removal efficiency of approximately 99% and was unaffected by presence of water vapor. The sorbent was subsequently commercially prepared by Süd Chemie to determine the viability of the sorbent for mass production. Subsequent testing showed that the commercially-synthesized sorbent possesses the same properties as the lab-synthesized equivalent. An innovative solid sorbent containing mixture of alkali earth and alkali compounds was developed for CO2 removal at 200 – 315°C from high pressure gas streams suitable for IGCC systems. The sorbent showed very high capacity for CO2 removal from a gas streams containing 28% CO2 at 200 °C and at 20 atm during a lab scale reactor test. This sorbent can be regenerated at 20 atm and at 375 °C utilizing a gas stream containing steam. High pressure enhanced the CO2 sorption process. Bench scale testing showed consistent capacities and regenerability. A unique high temperature solid sorbent was developed for CO2

  4. Development of an Automated Column Solid-Phase Extraction Cleanup of QuEChERS Extracts, Using a Zirconia-Based Sorbent, for Pesticide Residue Analyses by LC-MS/MS.

    PubMed

    Morris, Bruce D; Schriner, Richard B

    2015-06-01

    A new, automated, high-throughput, mini-column solid-phase extraction (c-SPE) cleanup method for QuEChERS extracts was developed, using a robotic X-Y-Z instrument autosampler, for analysis of pesticide residues in fruits and vegetables by LC-MS/MS. Removal of avocado matrix and recoveries of 263 pesticides and metabolites were studied, using various stationary phase mixtures, including zirconia-based sorbents, and elution with acetonitrile. These experiments allowed selection of a sorbent mixture consisting of zirconia, C18, and carbon-coated silica, that effectively retained avocado matrix but also retained 53 pesticides with <70% recoveries. Addition of MeOH to the elution solvent improved pesticide recoveries from zirconia, as did citrate ions in CEN QuEChERS extracts. Finally, formate buffer in acetonitrile/MeOH (1:1) was required to give >70% recoveries of all 263 pesticides. Analysis of avocado extracts by LC-Q-Orbitrap-MS showed that the method developed was removing >90% of di- and triacylglycerols. The method was validated for 269 pesticides (including homologues and metabolites) in avocado and citrus. Spike recoveries were within 70-120% and 20% RSD for 243 of these analytes in avocado and 254 in citrus, when calibrated against solvent-only standards, indicating effective matrix removal and minimal electrospray ionization suppression.

  5. Development of an Automated Column Solid-Phase Extraction Cleanup of QuEChERS Extracts, Using a Zirconia-Based Sorbent, for Pesticide Residue Analyses by LC-MS/MS.

    PubMed

    Morris, Bruce D; Schriner, Richard B

    2015-06-01

    A new, automated, high-throughput, mini-column solid-phase extraction (c-SPE) cleanup method for QuEChERS extracts was developed, using a robotic X-Y-Z instrument autosampler, for analysis of pesticide residues in fruits and vegetables by LC-MS/MS. Removal of avocado matrix and recoveries of 263 pesticides and metabolites were studied, using various stationary phase mixtures, including zirconia-based sorbents, and elution with acetonitrile. These experiments allowed selection of a sorbent mixture consisting of zirconia, C18, and carbon-coated silica, that effectively retained avocado matrix but also retained 53 pesticides with <70% recoveries. Addition of MeOH to the elution solvent improved pesticide recoveries from zirconia, as did citrate ions in CEN QuEChERS extracts. Finally, formate buffer in acetonitrile/MeOH (1:1) was required to give >70% recoveries of all 263 pesticides. Analysis of avocado extracts by LC-Q-Orbitrap-MS showed that the method developed was removing >90% of di- and triacylglycerols. The method was validated for 269 pesticides (including homologues and metabolites) in avocado and citrus. Spike recoveries were within 70-120% and 20% RSD for 243 of these analytes in avocado and 254 in citrus, when calibrated against solvent-only standards, indicating effective matrix removal and minimal electrospray ionization suppression. PMID:25702899

  6. Sol-gel derived sorbents

    DOEpatents

    Sigman, Michael E.; Dindal, Amy B.

    2003-11-11

    Described is a method for producing copolymerized sol-gel derived sorbent particles for the production of copolymerized sol-gel derived sorbent material. The method for producing copolymerized sol-gel derived sorbent particles comprises adding a basic solution to an aqueous metal alkoxide mixture for a pH.ltoreq.8 to hydrolyze the metal alkoxides. Then, allowing the mixture to react at room temperature for a precalculated period of time for the mixture to undergo an increased in viscosity to obtain a desired pore size and surface area. The copolymerized mixture is then added to an immiscible, nonpolar solvent that has been heated to a sufficient temperature wherein the copolymerized mixture forms a solid upon the addition. The solid is recovered from the mixture, and is ready for use in an active sampling trap or activated for use in a passive sampling trap.

  7. Sorbent characterization for FBC application

    SciTech Connect

    Pisupati, S.V.; Scaroni, A.W.

    1994-12-31

    Fluidized-bed boilers operating at both atmospheric and elevated pressures have received considerable attention from utilities and independent power producers because of their ability to remove SO{sub 2} from the flue gas during combustion and to minimize NO{sub x} production. The technology has advanced rapidly in the 1980s because of its adaptability to a range of fuel types, boiler capacities, and operating conditions without seriously compromising efficiency or performance. A sorbent, typically limestone or dolostone, is used in the fluidized-bed boiler to capture the combustion-generated SO{sub 2}. Many CFBC boiler operators are now realizing that optimizing sorbent usage is important for economical and environmentally acceptable operation of their plants. It is reported (mostly based on studies using a few sorbents) that particle size, porosity and pore size distribution, extent of sulfation, combustor temperature, pressure and CaCO{sub 3} content affect extent of sulfation.

  8. Enhanced durability of desulfurization sorbents for fluidized-bed applications

    SciTech Connect

    Gupta, R.P.; Gangwal, S.K.

    1992-11-01

    To extend the operating temperature range and further improve the durability of fluidizable sorbents, zinc titanate, another leading regenerable sorbent, was selected for development in the later part of this project. A number of zinc titanate formulations were prepared in the 50 to 300 [mu]m range using granulation and spray drying methods. Important sorbent preparation variables investigated included zinc to titanium ratio, binder type, binder amount, and various chemical additives such as cobalt and molybdenum. A number of sorbents selected on the basis of screening tests were subjected to bench-scale testing for 10 cycles at high temperature, high pressure (HTHP) conditions using the reactor system designed and constructed during the base program. This reactor system is capable of operation either as a 2.0 in. or 3.0 in. I.D. bubbling bed and is rated up to 20 atm operation at 871[degrees]C. Bench-scale testing variables included sorbent type, temperature (550 to 750[degrees]C), gas type (KRW or Texaco gasifier gas), steam content of coal gas, and fluidizing gas velocity (6 to 15 cm/s). The sorbents prepared by spray drying showed poor performance in terms of attrition resistance and chemical reactivity. On the other hand, the granulation method proved to be very successful. For example, a highly attrition-resistant zinc titanate formulation, ZT-4, prepared by granulation exhibited virtually no zinc loss and demonstrated a constant high reactivity and sulfur capacity over 10 cycles, i.e., approximately a 60 percent capacity utilization, with Texaco gas at 750[degrees]C, 15 cm/s fluidizing velocity and 15 atm pressure. The commercial potential of the granulation method for zinc titanate manufacture was demonstrated by preparing two 80 lb batches of sorbent with zinc to titanium mol ratios of 0.8 and 1.5.

  9. Enhanced durability of desulfurization sorbents for fluidized-bed applications

    SciTech Connect

    Gupta, R.P.; Gangwal, S.K.

    1992-11-01

    To extend the operating temperature range and further improve the durability of fluidizable sorbents, zinc titanate, another leading regenerable sorbent, was selected for development in the later part of this project. A number of zinc titanate formulations were prepared in the 50 to 300 {mu}m range using granulation and spray drying methods. Important sorbent preparation variables investigated included zinc to titanium ratio, binder type, binder amount, and various chemical additives such as cobalt and molybdenum. A number of sorbents selected on the basis of screening tests were subjected to bench-scale testing for 10 cycles at high temperature, high pressure (HTHP) conditions using the reactor system designed and constructed during the base program. This reactor system is capable of operation either as a 2.0 in. or 3.0 in. I.D. bubbling bed and is rated up to 20 atm operation at 871{degrees}C. Bench-scale testing variables included sorbent type, temperature (550 to 750{degrees}C), gas type (KRW or Texaco gasifier gas), steam content of coal gas, and fluidizing gas velocity (6 to 15 cm/s). The sorbents prepared by spray drying showed poor performance in terms of attrition resistance and chemical reactivity. On the other hand, the granulation method proved to be very successful. For example, a highly attrition-resistant zinc titanate formulation, ZT-4, prepared by granulation exhibited virtually no zinc loss and demonstrated a constant high reactivity and sulfur capacity over 10 cycles, i.e., approximately a 60 percent capacity utilization, with Texaco gas at 750{degrees}C, 15 cm/s fluidizing velocity and 15 atm pressure. The commercial potential of the granulation method for zinc titanate manufacture was demonstrated by preparing two 80 lb batches of sorbent with zinc to titanium mol ratios of 0.8 and 1.5.

  10. High Temperature Sorbents for Oxygen

    NASA Technical Reports Server (NTRS)

    Sharma, Pramod K. (Inventor)

    1996-01-01

    A sorbent capable of removing trace amounts of oxygen (ppt) from a gas stream at a high temperature above 200 C is introduced. The sorbent comprises a porous alumina silicate support such as zeolite containing from 1 to 10 percent by weight of ion exchanged transition metal such as copper or cobalt ions and 0.05 to 1.0 percent by weight of an activator selected from a platinum group metal such as platinum. The activation temperature, oxygen sorption and reducibility are all improved by the presence of the platinum activator.

  11. NOVEL MERCURY OXIDANT AND SORBENT FOR MERCURY EMISSIONS CONTROL FROM COAL-FIRED POWER PLANTS

    EPA Science Inventory

    The authors have successfully developed novel efficient and cost-effective sorbent and oxidant for removing mercury from power plant flue gases. These sorbent and oxidant offer great promise for controlling mercury emissions from coal-fired power plants burning a wide range of c...

  12. SIMULTANEOUS CONTROL OF HGO, SO2, AND NOX BY NOVEL OXIDIZED CALCIUM-BASED SORBENTS

    EPA Science Inventory

    The paper gives results of an investigation of two classes of calcium (Ca)-based sorbents (hydrated limes and silicate compounds). (NOTE: Efforts to develop multipollutant control strategies have demonstrated that adding certain oxidants to different classes of Ca-based sorbents...

  13. SIMULTANEOUS CONTROL OF HG(0), SO2, AND NOX BY NOVEL OXIDIZED CALCIUM-BASED SORBENTS

    EPA Science Inventory

    The paper gives results of an investigation of two classes of calcium (Ca)-based sorbents (hydrated limes and silicate compounds). {NOTE: Efforts to develop multipollutant control strategies have demonstrated that adding certain oxidants to different classes of Ca-based sorbents ...

  14. Boronated liposome development and evaluation

    SciTech Connect

    Hawthorne, M.F.

    1995-11-01

    The boronated liposome development and evaluation effort consists of two separate tasks. The first is the development of new boron compounds and the synthesis of known boron species with BNCT potential. These compounds are then encapsulated within liposomes for the second task, biodistribution testing in tumor-bearing mice, which examines the potential for the liposomes and their contents to concentrate boron in cancerous tissues.

  15. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    SciTech Connect

    David A. Green; Brian S. Turk; Jeffrey W. Portzer; Raghubir P. Gupta; William J. McMichael; Ya Liang; Tyler Moore; Douglas P. Harrison

    2003-08-01

    This report describes research conducted between April 1, 2003 and June 30, 2003 on the use of dry regenerable sorbents for concentration of carbon dioxide from flue gas. Grade 1 sodium bicarbonate performed similarly to grade 5 sodium bicarbonate in fixed bed testing in that activity improved after the first carbonation cycle and did not decline over the course of 5 cycles. Thermogravimetric analysis indicated that sodium bicarbonate sorbents produced by calcination of sodium bicarbonate are superior to either soda ash or calcined trona. Energy requirements for regeneration of carbon dioxide sorbents (either wet or dry) is of primary importance in establishing the economic feasibility of carbon dioxide capture processes. Recent studies of liquid amine sorption processes were reviewed and found to incorporate conflicting assumptions of energy requirements. Dry sodium based processes have the potential to be less energy intensive and thus less expensive than oxygen inhibited amine based systems. For dry supported sorbents, maximizing the active fraction of the sorbent is of primary importance in developing an economically feasible process.

  16. Optimizing the specific surface area of fly ash-based sorbents for flue gas desulfurization.

    PubMed

    Lee, K T; Bhatia, S; Mohamed, A R; Chu, K H

    2006-01-01

    High performance sorbents for flue gas desulfurization can be synthesized by hydration of coal fly ash, calcium sulfate, and calcium oxide. In general, higher desulfurization activity correlates with higher sorbent surface area. Consequently, a major aim in sorbent synthesis is to maximize the sorbent surface area by optimizing the hydration conditions. This work presents an integrated modeling and optimization approach to sorbent synthesis based on statistical experimental design and two artificial intelligence techniques: neural network and genetic algorithm. In the first step of the approach, the main and interactive effects of three hydration variables on sorbent surface area were evaluated using a full factorial design. The hydration variables of interest to this study were hydration time, amount of coal fly ash, and amount of calcium sulfate and the levels investigated were 4-32 h, 5-15 g, and 0-12 g, respectively. In the second step, a neural network was used to model the relationship between the three hydration variables and the sorbent surface area. A genetic algorithm was used in the last step to optimize the input space of the resulting neural network model. According to this integrated modeling and optimization approach, an optimum sorbent surface area of 62.2m(2)g(-1) could be obtained by mixing 13.1g of coal fly ash and 5.5 g of calcium sulfate in a hydration process containing 100ml of water and 5 g of calcium oxide for a fixed hydration time of 10 h.

  17. PROCEEDINGS: MULTIPOLLUTANT SORBENT REACTIVITY WORKSHOP

    EPA Science Inventory

    The report is a compilation of technical papers and visual aids presented by representatives of industry, academia, and government agencies at a workshop on multipollutant sorbent reactivity that was held at EPA's Environmental Research Center in Research Triangle Park, NC, on Ju...

  18. Magnetic solid-phase extraction using carbon nanotubes as sorbents: a review.

    PubMed

    Herrero-Latorre, C; Barciela-García, J; García-Martín, S; Peña-Crecente, R M; Otárola-Jiménez, J

    2015-09-10

    Magnetic solid-phase extraction (M-SPE) is a procedure based on the use of magnetic sorbents for the separation and preconcentration of different organic and inorganic analytes from large sample volumes. The magnetic sorbent is added to the sample solution and the target analyte is adsorbed onto the surface of the magnetic sorbent particles (M-SPs). Analyte-M-SPs are separated from the sample solution by applying an external magnetic field and, after elution with the appropriate solvent, the recovered analyte is analyzed. This approach has several advantages over traditional solid phase extraction as it avoids time-consuming and tedious on-column SPE procedures and it provides a rapid and simple analyte separation that avoids the need for centrifugation or filtration steps. As a consequence, in the past few years a great deal of research has been focused on M-SPE, including the development of new sorbents and novel automation strategies. In recent years, the use of magnetic carbon nanotubes (M-CNTs) as a sorption substrate in M-SPE has become an active area of research. These materials have exceptional mechanical, electrical, optical and magnetic properties and they also have an extremely large surface area and varied possibilities for functionalization. This review covers the synthesis of M-CNTs and the different approaches for the use of these compounds in M-SPE. The performance, general characteristics and applications of M-SPE based on magnetic carbon nanotubes for organic and inorganic analysis have been evaluated on the basis of more than 110 references. Finally, some important challenges with respect the use of magnetic carbon nanotubes in M-SPE are discussed.

  19. KINETICS OF Mn-BASED SORBENTS FOR HOT COAL GAS DESULFURIZATION

    SciTech Connect

    J.J. BERNS; K.A. SADECKI; M.T. HEPWORTH

    1997-09-15

    temperature. Sorbent also showed 30 to 53% loss of its strength over four cycles of sulfidation and regeneration. The former being sorbent indurated at 1115 o C and the prior being sorbent indurated at 1100 o C. A mathematical model was developed to describe the reaction of H 2 S with the mixed metal oxide in a fixed-bed reactor, where the individual pellets react according to the shrinking core model. The effective diffusivity within a single pellet was estimated by adjusting its value until a good match between the experimental and model H 2 S breakthrough curves was obtained. Predicted sorbent conversion at the conclusion of test FB3A compared well with experimental sulfur analysis.

  20. Development of a method based on sorbent trapping followed by solid-phase microextraction for the determination of synthetic musks in indoor air.

    PubMed

    Regueiro, Jorge; Garcia-Jares, Carmen; Llompart, Maria; Lamas, J Pablo; Cela, Rafael

    2009-04-01

    Synthetic musks are extensively used as fragrance components in a wide range of consumer and personal care products such as detergents, shampoos, perfumes and other cosmetic products. Amongst them, galaxolide and tonalide have become ubiquitous pollutants due to their continuous releasing into the environment. Because of their nature as artificial fragrances, inhalation should be considered as an important exposure pathway, especially in indoor environments. However, up to now very few studies have been carried out to determine these emergent pollutants indoors. In this work, a simple and highly sensitive methodology for the analysis of synthetic musk fragrances in indoor air samples is presented. The proposed methodology combines solid-phase extraction (SPE) and solid-phase microextraction (SPME), followed by gas chromatography-mass spectrometry (GC/MS). To the best of our knowledge, this is the first method based on SPME for the analysis of musks in air. By active sampling, musks present in air were adsorbed onto 25mg Tenax and then transferred to a SPME fiber in the headspace mode (HS). An experimental design strategy was used to optimize main factors potentially affecting the microextraction process such as fiber coating, temperature and the addition of a microvolume of organic solvent to the solid sorbent prior to SPME. Breakthrough of the SPE sorbent was studied from 1 to 10m(3) without significant losses. Recovery studies were performed at two concentration levels (2 and 20ngm(-3)), obtaining quantitative recoveries (>/=85%) by external calibration. A comprehensive study was performed in order to estimate the limits of detection taking into account the contamination risks and laboratory blanks. Values at the sub ngm(-3) level were achieved for all the target compounds sampling 5m(3) air. External calibration, not requiring the complete sampling process, demonstrated to be suitable for the quantification of all musk compounds. Finally, several indoor

  1. Large Particle Titanate Sorbents

    SciTech Connect

    Taylor-Pashow, K.

    2015-10-08

    This research project was aimed at developing a synthesis technique for producing large particle size monosodium titanate (MST) to benefit high level waste (HLW) processing at the Savannah River Site (SRS). Two applications were targeted, first increasing the size of the powdered MST used in batch contact processing to improve the filtration performance of the material, and second preparing a form of MST suitable for deployment in a column configuration. Increasing the particle size should lead to improvements in filtration flux, and decreased frequency of filter cleaning leading to improved throughput. Deployment of MST in a column configuration would allow for movement from a batch process to a more continuous process. Modifications to the typical MST synthesis led to an increase in the average particle size. Filtration testing on dead-end filters showed improved filtration rates with the larger particle material; however, no improvement in filtration rate was realized on a crossflow filter. In order to produce materials suitable for column deployment several approaches were examined. First, attempts were made to coat zirconium oxide microspheres (196 µm) with a layer of MST. This proved largely unsuccessful. An alternate approach was then taken synthesizing a porous monolith of MST which could be used as a column. Several parameters were tested, and conditions were found that were able to produce a continuous structure versus an agglomeration of particles. This monolith material showed Sr uptake comparable to that of previously evaluated samples of engineered MST in batch contact testing.

  2. Direct sulfur recovery during sorbent regeneration. Final report

    SciTech Connect

    Nelson, S.G.; Little, R.C.

    1993-08-01

    The objective of this research project was to improve the direct elemental sulfur yields that occur during the regeneration of SO{sub 2}-saturated MgO-vermiculite sorbents (MagSorbents) by examining three approaches or strategies. The three approaches were regeneration-gas recycle, high-pressure regeneration, and catalytic reduction of the SO{sub 2} gas using a new catalyst developed by Research Triangle Institute (RTI). Prior to the project, Sorbent Technologies Corporation (Sorbtech) had developed a sorbent-regeneration process that yielded directly a pure elemental sulfur product. In the process, typically about 25 to 35 percent of the liberated S0{sub 2} was converted directly to elemental sulfur. The goal of this project was to achieve a conversion rate of over 90 percent. Good success was attained in the project. About 90 percent or more conversion was achieved with two of the approaches that were examined, regeneration-gas recycle and use of the RTI catalyst. Of these approaches, regeneration-gas recycle gave the best results (essentially 100 percent conversion in some cases). In the regeneration-gas recycle approach, saturated sorbent is simply heated to about 750{degree}C in a reducing gas (methane) atmosphere. During heating, a gas containing elemental sulfur, water vapor, H{sub 2}S, S0{sub 2}, and C0{sub 2} is evolved. The elemental sulfur and water vapor in the gas stream are condensed and removed, and the remaining gas is recycled back through the sorbent bed. After several recycles, the S0{sub 2} and H{sub 2}S completely disappear from the gas stream, and the stream contains only elemental sulfur, water vapor and C0{sub 2}.

  3. Investigation on durability and reactivity of promising metal oxide sorbents during sulifidation and regeneration: Technical progress report for July 1--September 30, 1996

    SciTech Connect

    Kwon, K.C.

    1996-11-01

    The main objectives of this research project during this quarter are to formulate metal oxide sorbents using various ingredients as well as formulation conditions, and test reactivity of formulated metal oxide sorbents with hydrogen sulfide for 120 seconds at 550{degrees}C, and develop a formula of a sorbent suitable for the removal of hydrogen sulfide from hot coal gases. Metal oxide sorbents were formulated with zinc oxide as an active sorbent ingredient, and titanium oxide as a supporting metal oxide. Various additives such as Al, Ce, Zr, Cu, Co, Ni, Mn, Cr and Ca were utilized to enhance sulfur-removal capacity of formulated metal oxide sorbents. The additives Cu and Co appear to enhance reactivity of sorbents in the reaction with wet hot hydrogen sulfide at 550{degrees}C. Durability of formulated sorbents appears to improve with kaolin binder in comparison with bentonite binder. Durability of formulated sorbents appears to improve with increased calcination durations. Reactivity of sorbents formulated with Co additive appears to decrease with increased calcination durations at the calcination temperature of 860{degrees}C. Reactivity of sorbents formulated with Cu additive appears to increase with calcination durations. Reactivity of sorbents formulated without additive appears to be independent of calcination durations.

  4. COMBINED SORBENT/CATALYST MEDIA FOR DESTRUCTION OF HALOGENATED VOCS

    EPA Science Inventory

    Several chromium modified zeolites have been developed and tested for their ability to physisorb chlorinated VOCs (CVOCs) at ambient and then catalytically destroy them at elevated temperatures (ca. 300 degrees C). These dual function materials, which act as both sorbents and cat...

  5. STRUCTURAL CHANGES IN SURFACTANT-MODIFIED SORBENTS DURING FURNACE INJECTION

    EPA Science Inventory

    A calcium hydroxide [Ca(OH)2] sorbent modified by the addition of calcium lignosulfonate has recently been developed for use in the Environmental Protection Agency's limestone injection multistage burner process. The increased reactivity with sulfur dioxide (SO2) displayed by thi...

  6. High capacity carbon dioxide sorbent

    DOEpatents

    Dietz, Steven Dean; Alptekin, Gokhan; Jayaraman, Ambalavanan

    2015-09-01

    The present invention provides a sorbent for the removal of carbon dioxide from gas streams, comprising: a CO.sub.2 capacity of at least 9 weight percent when measured at 22.degree. C. and 1 atmosphere; an H.sub.2O capacity of at most 15 weight percent when measured at 25.degree. C. and 1 atmosphere; and an isosteric heat of adsorption of from 5 to 8.5 kilocalories per mole of CO.sub.2. The invention also provides a carbon sorbent in a powder, a granular or a pellet form for the removal of carbon dioxide from gas streams, comprising: a carbon content of at least 90 weight percent; a nitrogen content of at least 1 weight percent; an oxygen content of at most 3 weight percent; a BET surface area from 50 to 2600 m.sup.2/g; and a DFT micropore volume from 0.04 to 0.8 cc/g.

  7. Decontamination formulation with sorbent additive

    DOEpatents

    Tucker; Mark D. , Comstock; Robert H.

    2007-10-16

    A decontamination formulation and method of making that neutralizes the adverse health effects of both chemical and biological compounds, especially chemical warfare (CW) and biological warfare (BW) agents, and toxic industrial chemicals. The formulation provides solubilizing compounds that serve to effectively render the chemical and biological compounds, particularly CW and BW compounds, susceptible to attack, and at least one reactive compound that serves to attack (and detoxify or kill) the compound. The formulation includes at least one solubilizing agent, a reactive compound, a bleaching activator, a sorbent additive, and water. The highly adsorbent, water-soluble sorbent additive (e.g., sorbitol or mannitol) is used to "dry out" one or more liquid ingredients, such as the liquid bleaching activator (e.g., propylene glycol diacetate or glycerol diacetate) and convert the activator into a dry, free-flowing powder that has an extended shelf life, and is more convenient to handle and mix in the field.

  8. Sorbent Testing for Solidification of Organic Plutonium/Uranium Extraction Waste - Phase IV

    SciTech Connect

    Bickford, J.L.; Joyce, H.O.; Holmes-Burns, H.

    2006-07-01

    The U.S. Department of Energy (DOE) is evaluating various sorbents to solidify and immobilize hazardous constituents of the organic fraction of plutonium/uranium extraction (PUREX) process waste at the Savannah River Site (SRS).[5] The purpose of the solidification is to provide a cost-effective alternative to incineration of the waste. Incineration at the Consolidated Incinerator Facility (CIF) at SRS is currently identified as the treatment technology for PUREX waste. However, the CIF is not in operation at this time, so SRS is interested in pursuing alternatives to incineration for treatment of this waste. The DOE Western Environmental Technology Office in Butte, MT was designated as the facility for conducting the sorbent testing and evaluation for the organic PUREX waste surrogate. MSE Technology Applications, Inc. tested and evaluated two clay and two polymer sorbents with the capability of solidifying organic PUREX waste. A surrogate organic PUREX waste recipe was utilized, and sorbents were tested and evaluated at bench-scale, 22-liter (5-gallon) scale, and 242-liter (55-gallon) scale. This paper presents experimental results evaluating four sorbent materials including: Imbiber Beads{sup TM} IMB230301-R, Nochar A610 Petrobond{sup TM}, Petroset II{sup TM}, and Petroset II Granular{sup TM}. Previous work at SRS indicated that these products could solidify organic PUREX waste on a bench scale [1]. The sorbents were evaluated using operational criteria and final wasteform properties. Operational criteria included: sorbent capacity; sorption rate; sorbent handling; and mixing requirements. Final wasteform evaluation properties included: ignitability; thermal stability; offgas generation, leachability tests and volumetric expansion. Bench-scale tests, 22-liter (5-gallon) tests, and initial 242-liter (55-gallon) tests are complete. This paper summarizes the results of the bench-scale, 22-liter (5-gallon) scale, and 242-liter (55-gallon) scale tests performed

  9. Functional Sorbents for Selective Capture of Plutonium, Americium, Uranium, and Thorium in Blood

    SciTech Connect

    Yantasee, Wassana; Sangvanich, Thanapon; Creim, Jeffrey A.; Pattamakomsan, Kanda; Wiacek, Robert J.; Fryxell, Glen E.; Addleman, Raymond S.; Timchalk, Charles

    2010-09-01

    Nano-engineered solid sorbents for chelation of actinides (239Pu, 241Am, uranium, thorium) from human blood were developed and evaluated in vitro. These sorbents, known as the self-assembled monolayer on mesoporous supports (SAMMSTM), are hybrid materials created from attachment of organic moieties onto extremely high surface area mesoporous silica. The organic moieties known to be effective at capturing actinides including three isomers of hydroxypyridinone, diphosphonic acid, acetamide phosphonic acid, glycinyl urea, and diethylenetriamine pentaacetate analog were evaluated. SAMMS are being reported elsewhere as potential candidates for orally administered drug for radionuclide decorporation. Herein, actinide decorporation of SAMMS in blood were evaluated to assess their viability for sorbent hemoperfusion in renal insufficient patients, whose kidney clear radionuclides at very slow rate. Sorption affinity (Kd), sorption rate, selectivity, and stability of SAMMS were measured in batch contact experiments. An isomer of hydroxypyridinone (3,4-HOPO) on SAMMS demonstrated the highest affinity for decorporation of all four actinides and outperformed the DTPA analog on SAMMS and on commercial resins by a factor of 103-fold in term of affinity. A fifty percent reduction of actinides in blood was achieved within minutes with no evidence of protein fouling and material leaching in blood after 24 hr of contact time. Less than 0.4 wt.% of Si was dissolved from 3,4-HOPO-SAMMS across the pH of 0 to 8. The engineered form of SAMMS (bead format) was further evaluated in a 100-fold scaled-down hemoperfusion device and showed no blood clotting after 2 hr. A 0.2 g of SAMMS could reduce 50 wt.% of 100 ppb uranium in 50 mL of plasma in just 18 min and that of 500 dpm mL-1 in just 24 min. 3,4-HOPO-SAMMS has a long shelf-life in air and at room temperature for at least 8 years, indicating their feasibility for stockpiling in preparedness for emergency.

  10. Photopatternable sorbent and functionalized films

    DOEpatents

    Grate, Jay W.; Nelson, David A.

    2006-01-31

    A composition containing a polymer, a crosslinker and a photo-activatable catalyst is placed on a substrate. The composition is exposed to a predetermined pattern of light, leaving an unexposed region. The light causes the polymer to become crosslinked by hydrosilylation. A solvent is used to remove the unexposed composition from the substrate, leaving the exposed pattern to become a sorbent polymer film that will absorb a predetermined chemical species when exposed to such chemical species.

  11. Chemical modification of hygroscopic magnesium carbonate into superhydrophobic and oleophilic sorbent suitable for removal of oil spill in water

    NASA Astrophysics Data System (ADS)

    Patowary, Manoj; Ananthakrishnan, Rajakumar; Pathak, Khanindra

    2014-11-01

    The wettability of hygroscopic magnesium carbonate has been modified to develop a superhydrophobic and oleophilic sorbent for oil spill clean-ups via a simple chemical process using palmitic acid. The prepared material was characterized using X-ray diffraction, Fourier transform infra-red spectroscopy, and scanning electron microscopy. Wettability test infers that the sorbent has a static water contact angle of 154 ± 1°, thereby indicating its superhydrophobic character. The sorbent was capable of scavenging oil for about three times its weight, as determined from oil sorption studies, carried out using the sorbent on model oil-water mixture. Interestingly, the chemically modified sorbent has high selectivity, buoyancy, and rate of uptake of oil. Further, the reusability studies confirm the repeatable usage of the sorbent and its efficacy in oil spill remediation.

  12. Mercury sorption mechanisms and control by calcium-based sorbents. Report for September 1994--April 1996

    SciTech Connect

    Krishnan, S.V.; Bakhteyar, H.; Sedman, C.B.

    1996-01-01

    The paper reports results of experiments to study elemental mercury (Hg) and mercuric chloride (HgCl[sub 2]) capture by several calcium-based sorbents and their performance compared with an activated carbon used in earlier bench- and pilot-scale tests. Elemental Hg and HgCl[sub 2] concentrations were roughly 2--3 ppb in a simulated flue gas. Among the calcium-based sorbents evaluated in the study are reagent grade hydrated lime, a mixture of fly ash and hydrated lime (Advacate), and a modified Advacate. Capture of elemental Hg and HgCl[sub 2] by these sorbents was studied at 100 C.

  13. Composition modification of zinc titanate sorbents for hot gas desulfurization. Quarterly report, 1 December 1994--28 February 1995

    SciTech Connect

    Swisher, J.H.; Datta, R.K.

    1995-12-31

    For new coal gasification systems, zinc titanate sorbents are being developed to remove sulfur from the hot product gas prior to its use in combined cycle turbines and high temperature fuel cells. Although most of the properties of these sorbents are very attractive, there are still concerns about durability over many sulfidation-regeneration cycles and zinc losses due to vaporization. Doping the zinc titanate with other metal ions could alleviate both concerns, which are the objectives of this project. A screening study was completed during the second quarter in which Ni, Cr, Cu, Mg, and Al were evaluated as dopants in zinc titanate. Measurements that were made include solubility, crush strength, and sulfidation-regeneration behavior in a thermogravimetric analyzer. A formulation containing Cr showed the most promise. It and other formulations containing Cr will be emphasized during the remainder of the year. Fixed bed experiments will start during the third quarter.

  14. Development and validation of a solid-phase extraction method using anion exchange sorbent for the analysis of cannabinoids in plasma and serum by gas chromatography-mass spectrometry.

    PubMed

    Gasse, Angela; Pfeiffer, Heidi; Köhler, Helga; Schürenkamp, Jennifer

    2016-07-01

    The aim of this work was to develop and validate a solid-phase extraction (SPE) method for the analysis of cannabinoids with emphasis on a very extensive and effective matrix reduction in order to ensure constant good results in selectivity and sensitivity regardless of the applied measuring technology. This was obtained by the use of an anion exchange sorbent (AXS) and the purposive ionic interaction between matrix components and this sorbent material. In a first step, the neutral cannabinoids ∆9-tetrahydrocannabinol (THC) and 11-hydroxy-∆9-tetrahydrocannabinol (11-OH-THC) were eluted, leaving 11-nor-9-carboxy-∆9-tetrahydrocannabinol (THC-COOH) and the main interfering matrix components bound to the AXS. In a second step, exploiting differences in pH and polarity, it was possible to separate matrix components and THC-COOH, thereby yielding a clean elution of THC-COOH into the same collecting tube as THC and 11-OH-THC. Even when using a simple measuring technology like gas chromatography with single quadrupole mass spectrometry, this two-step elution allows for an obvious decrease in number and intensity of matrix interference in the chromatogram. Hence, in both plasma and serum, the AXS extracts resulted in very good selectivity. Limits of detection and limits of quantification were below 0.25 and 0.35 ng/mL for the neutral cannabinoids in both matrices, 2.0 and 3.0 ng/mL in plasma and 1.6 and 3.3 ng/mL in serum for THC-COOH. The recoveries were ≥79.8 % for all analytes. Interday and intraday imprecisions ranged from 0.8 to 6.1 % relative standard deviation, and accuracy bias ranged from -12.6 to 3.6 %.

  15. Development and validation of a solid-phase extraction method using anion exchange sorbent for the analysis of cannabinoids in plasma and serum by gas chromatography-mass spectrometry.

    PubMed

    Gasse, Angela; Pfeiffer, Heidi; Köhler, Helga; Schürenkamp, Jennifer

    2016-07-01

    The aim of this work was to develop and validate a solid-phase extraction (SPE) method for the analysis of cannabinoids with emphasis on a very extensive and effective matrix reduction in order to ensure constant good results in selectivity and sensitivity regardless of the applied measuring technology. This was obtained by the use of an anion exchange sorbent (AXS) and the purposive ionic interaction between matrix components and this sorbent material. In a first step, the neutral cannabinoids ∆9-tetrahydrocannabinol (THC) and 11-hydroxy-∆9-tetrahydrocannabinol (11-OH-THC) were eluted, leaving 11-nor-9-carboxy-∆9-tetrahydrocannabinol (THC-COOH) and the main interfering matrix components bound to the AXS. In a second step, exploiting differences in pH and polarity, it was possible to separate matrix components and THC-COOH, thereby yielding a clean elution of THC-COOH into the same collecting tube as THC and 11-OH-THC. Even when using a simple measuring technology like gas chromatography with single quadrupole mass spectrometry, this two-step elution allows for an obvious decrease in number and intensity of matrix interference in the chromatogram. Hence, in both plasma and serum, the AXS extracts resulted in very good selectivity. Limits of detection and limits of quantification were below 0.25 and 0.35 ng/mL for the neutral cannabinoids in both matrices, 2.0 and 3.0 ng/mL in plasma and 1.6 and 3.3 ng/mL in serum for THC-COOH. The recoveries were ≥79.8 % for all analytes. Interday and intraday imprecisions ranged from 0.8 to 6.1 % relative standard deviation, and accuracy bias ranged from -12.6 to 3.6 %. PMID:27072011

  16. Effective date of requirement for premarket approval for transilluminator for breast evaluation and sorbent hemoperfusion system (SHS) devices for the treatment of hepatic coma and metabolic disturbances; reclassification of SHS and devices for the treatment of poisoning and drug overdose. Final order.

    PubMed

    2014-01-17

    The Food and Drug Administration (FDA) is issuing a final order to require the filing of a premarket approval application (PMA) for the transilluminator for breast evaluation and sorbent hemoperfusion system (SHS) devices for the treatment of hepatic coma and metabolic disturbances and to reclassify SHS devices for the treatment of poisoning and drug overdose, a preamendments class III device, into class II (special controls). PMID:24443766

  17. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report No. 1, October--December 1986

    SciTech Connect

    Jha, M.C.; Baltich, L.K.

    1987-02-23

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  18. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report 2, January--March 1987

    SciTech Connect

    Jha, M.C.; Baltich, L.K.; Berggren, M.H.

    1987-05-18

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  19. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Volume 1, Bench-scale testing and analysis

    SciTech Connect

    Jha, M.C.; Berggren, M.H.

    1989-05-02

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  20. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report No. 3, April--June 1987

    SciTech Connect

    Jha, M.C.; Baltich, L.K.; Berggren, M.H.

    1987-08-28

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  1. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report 8, July--September 1988

    SciTech Connect

    Jha, M.C.; Berggren, M.H.

    1988-11-14

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  2. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report 7, April--June 1988

    SciTech Connect

    Jha, M.C.; Berggren, M.H.

    1988-08-19

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  3. SCALE-UP OF ADVANCED HOT-GAS DESULFURIZATION SORBENTS

    SciTech Connect

    K. JOTHIMURUGESAN; S.K. GANGWAL

    1998-03-01

    The objective of this study was to develop advanced regenerable sorbents for hot gas desulfurization in IGCC systems. The specific objective was to develop durable advanced sorbents that demonstrate a strong resistance to attrition and chemical deactivation, and high sulfidation activity at temperatures as low as 343 C (650 F). Twenty sorbents were synthesized in this work. Details of the preparation technique and the formulations are proprietary, pending a patent application, thus no details regarding the technique are divulged in this report. Sulfidations were conducted with a simulated gas containing (vol %) 10 H{sub 2}, 15 CO, 5 CO{sub 2}, 0.4-1 H{sub 2}S, 15 H{sub 2}O, and balance N{sub 2} in the temperature range of 343-538 C. Regenerations were conducted at temperatures in the range of 400-600 C with air-N{sub 2} mixtures. To prevent sulfation, catalyst additives were investigated that promote regeneration at lower temperatures. Characterization were performed for fresh, sulfided and regenerated sorbents.

  4. Surface functionalized nanostructured ceramic sorbents for the effective collection and recovery of uranium from seawater.

    PubMed

    Chouyyok, Wilaiwan; Pittman, Jonathan W; Warner, Marvin G; Nell, Kara M; Clubb, Donald C; Gill, Gary A; Addleman, R Shane

    2016-07-28

    The ability to collect uranium from seawater offers the potential for a nearly limitless fuel supply for nuclear energy. We evaluated the use of functionalized nanostructured sorbents for the collection and recovery of uranium from seawater. Extraction of trace minerals from seawater and brines is challenging due to the high ionic strength of seawater, low mineral concentrations, and fouling of surfaces over time. We demonstrate that rationally assembled sorbent materials that integrate high affinity surface chemistry and high surface area nanostructures into an application relevant micro/macro structure enables collection performance that far exceeds typical sorbent materials. High surface area nanostructured silica with surface chemistries composed of phosphonic acid, phosphonates, 3,4 hydroxypyridinone, and EDTA showed superior performance for uranium collection. A few phosphorous-based commercial resins, specifically Diphonix and Ln Resin, also performed well. We demonstrate an effective and environmentally benign method of stripping the uranium from the high affinity sorbents using inexpensive nontoxic carbonate solutions. The cyclic use of preferred sorbents and acidic reconditioning of materials was shown to improve performance. Composite thin films composed of the nanostructured sorbents and a porous polymer binder are shown to have excellent kinetics and good capacity while providing an effective processing configuration for trace mineral recovery from solutions. Initial work using the composite thin films shows significant improvements in processing capacity over the previously reported sorbent materials. PMID:27184739

  5. SO2 retention by reactivated CaO-based sorbent from multiple CO2 capture cycles.

    PubMed

    Manovic, Vasilije; Anthony, Edward J

    2007-06-15

    This paper examines the reactivation of spent sorbent, produced from multiple CO2 capture cycles, for use in SO2 capture. CaO-based sorbent samples were obtained from Kelly Rock limestone using three particle size ranges, each containing different impurities levels. Using a thermogravimetric analyzer (TGA), the sulfation behavior of partially sulfated and unsulfated samples obtained after multiple calcination-carbonation cycles in a tube furnace (TF), following steam reactivation in a pressurized reactor, is examined. In addition, samples calcined/sintered under different conditions after hydration are also examined. The results show that suitably treated spent sorbent has better sulfation characteristics than that of the original sorbent. Thus for example, after 2 h sulfation, > 80% of the CaO was sulfated. In addition, the sorbent showed significant activity even after 4 h when > 95% CaO was sulfated. The results were confirmed by X-ray diffraction (XRD) analysis, which showed that, by the end of the sulfation process, samples contained CaSO4 with only traces of unreacted CaO. The superior behavior of spent reactivated sorbent appears to be due to swelling of the sorbent particles during steam hydration. This enables the development of a more suitable pore surface area and pore volume distribution for sulfation, and this has been confirmed by N2 adsorption-desorption isotherms and the Barrett-Joyner-Halenda (BJH) method. The surface area morphology of sorbent after reactivation was examined by scanning electron microscopy (SEM). Ca(OH)2 crystals were seen, which displayed their regular shape, and their elemental composition was confirmed by energy-dispersive X-ray (EDX) analysis. The improved characteristics of spent reactivated sorbent in comparison to the original and to the sorbent calcined under different conditions and hydrated indicate the beneficial effect of CO2 cycles on sorbent reactivation and subsequent sulfation. These results allow us to propose a

  6. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    SciTech Connect

    David A. Green; Brian S. Turk; Jeffrey W. Portzer; Raghubir P. Gupta; William J. McMichael; Thomas Nelson

    2004-04-01

    This report describes research conducted between January 1, 2004 and March 31, 2004 on the use of dry regenerable sorbents for removal of carbon dioxide from flue gas. RTI has produced laboratory scale batches (approximately 300 grams) of supported sorbents (composed of 20 to 40% sodium carbonate) with high surface area and acceptable activity. Initial rates of weight gain of the supported sorbents when exposed to a simulated flue gas exceeded that of 100% calcined sodium bicarbonate. One of these sorbents was tested through six cycles of carbonation/calcination by thermogravimetric analysis and found to have consistent carbonation activity. Kinetic modeling of the regeneration cycle on the basis of diffusion resistance at the particle surface is impractical, because the evolving gases have an identical composition to those assumed for the bulk fluidization gas. A kinetic model of the reaction has been developed on the basis of bulk motion of water and carbon dioxide at the particle surface (as opposed to control by gas diffusion). The model will be used to define the operating conditions in future laboratory- and pilot-scale testing.

  7. The New Environment for Development Evaluation

    ERIC Educational Resources Information Center

    Picciotto, Robert

    2007-01-01

    The millennium development goals have created new challenges for development evaluation. The main unit of account has shifted to the country level. Evaluation ownership must move from donor agencies to developing countries. The recognition that rich countries have development obligations is opening up evaluation frontiers beyond aid. A…

  8. Modified Hydra Bioassay to Evaluate the Toxicity of Multiple Mycotoxins and Predict the Detoxification Efficacy of a Clay-Based Sorbent

    PubMed Central

    Brown, KA; Mays, T; Romoser, A; Marroquin-Cardona, A; Mitchell, NJ; Elmore, SE; Phillips, TD

    2013-01-01

    Food shortages and lack of food supply regulation in developing countries often leads to chronic exposure of vulnerable populations to hazardous mixtures of mycotoxins, including aflatoxin B1 (AFB1) and fumonisin B1 (FB1). A refined calcium montmorillonite clay (i.e. UPSN) has been reported to tightly bind these toxins, thereby decreasing bioavailability in humans and animals. Hence, our objectives in the present work were to examine the ability of UPSN to bind mixtures of AFB1 and FB1at gastrointestinally relevant pH in vitro, and to utilize a rapid in vivo bioassay to evaluate AFB1 and FB1 toxicity and UPSN efficacy. Isothermal sorption data indicated tight AFB1 binding to UPSN surfaces at both pH 2.0 and 6.5, but substantially more FB1 bound at pH 2.0 than 6.5. Site-specific competition occurred between the toxins when exposed to UPSN in combination. Importantly, treatment with UPSN resulted in significant protection to mycotoxin-exposed hydra maintained at pH 6.9-7.0. Hydra were exposed to FB1, AFB1 and FB1/AFB1 combinations with and without UPSN. Toxic response over 92 hours was rated based on morphology and mortality. Hydra assay results indicated a minimum effective concentration (MEC) of 20 μg/mLfor AFB1, while the MEC for FB1 was not reached. The MEC for co-exposure was 400 μg/mL FB1 + 10 μg/mL AFB1. This study demonstrates that UPSN sorbs both mycotoxins tightly at physiologically relevant pH levels, resulting in decreased bioavailability, and that a modified hydra bioassay can be used as an initial screen in vivo to predict efficacy of toxin binding agents. PMID:23047854

  9. Modified hydra bioassay to evaluate the toxicity of multiple mycotoxins and predict the detoxification efficacy of a clay-based sorbent.

    PubMed

    Brown, K A; Mays, T; Romoser, A; Marroquin-Cardona, A; Mitchell, N J; Elmore, S E; Phillips, T D

    2014-01-01

    Food shortages and a lack of food supply regulation in developing countries often leads to chronic exposure of vulnerable populations to hazardous mixtures of mycotoxins, including aflatoxin B(1) (AFB(1)) and fumonisin B(1) (FB(1)). A refined calcium montmorillonite clay [i.e. uniform particle size NovaSil (UPSN)] has been reported to tightly bind these toxins, thereby decreasing bioavailability in humans and animals. Hence, our objectives in the present study were to examine the ability of UPSN to bind mixtures of AFB(1) and FB(1) at gastrointestinally relevant pH in vitro, and to utilize a rapid in vivo bioassay to evaluate AFB(1) and FB(1) toxicity and UPSN efficacy. Isothermal sorption data indicated tight AFB(1) binding to UPSN surfaces at both pH 2.0 and 6.5, but substantially more FB(1) bound at pH 2.0 than 6.5. Site-specific competition occurred between the toxins when exposed to UPSN in combination. Importantly, treatment with UPSN resulted in significant protection to mycotoxin-exposed hydra maintained at pH 6.9-7.0. Hydra were exposed to FB(1), AFB(1) and FB(1) /AFB(1) combinations with and without UPSN. A toxic response over 92 h was rated based on morphology and mortality. Hydra assay results indicated a minimum effective concentration (MEC) of 20 µg ml(-1) for AFB(1), whereas the MEC for FB(1) was not reached. The MEC for co-exposure was 400 µg ml(-1) FB(1) + 10 µg ml(-1) AFB(1). This study demonstrates that UPSN sorbs both mycotoxins tightly at physiologically relevant pH levels, resulting in decreased bioavailability, and that a modified hydra bioassay can be used as an initial screen in vivo to predict efficacy of toxin-binding agents.

  10. Method and system to reclaim functional sites on a sorbent contaminated by heat stable salts

    DOEpatents

    Krutka, Holly; Sjostrom, Sharon; Morris, William J.

    2016-03-08

    The objective of this invention is to develop a method to reclaim functional sites on a CO.sub.2 sorbent that have reacted with an acid gas (other than CO.sub.2) to form heat stable salts (HSS). HSS are a significant concern for dry sorbent based CO.sub.2 capture because over time the buildup of HSS will reduce the overall functionality of the CO.sub.2 sorbent. A chemical treatment can remove the non-CO.sub.2 acid gas and reclaim functional sites that can then be used for further CO.sub.2 adsorption.

  11. SO2-Resistant Immobilized Amine Sorbents for CO2 Capture

    SciTech Connect

    Tumuluri, Uma

    2014-01-01

    The solid amine sorbent for CO2 capture process has advantages of simplicity and low operating cost compared to the MEA (monoethanolamine) process. Solid amine sorbents reported so far suffered from either low CO2 capture capacity or low stability in the flue gas environment. This project is aimed at developing a SO2-resistant solid amine sorbent for capturing CO2 from coal–fired power plants with SCR/FGD which emits SO2ranging from 15 to 30 ppm and NO ranging from 5 to 10 ppm. The amine sorbent we developed in a previous project degraded rapidly with 65% decrease in the initial capture capacity in presence of 1% SO2. This amine sorbent was further modified by coating with polyethyleneglycol (PEG) to increase the SO2-resistance. Polyethylene glycol (PEG) was found to decrease the SO2-amine interaction, resulting in the decrease in the maximum SO desorption temperature (Tmax ) of amine sorbent. The PEG-coated amine sorbent exhibited higher stability with only 40% decrease in the initial capture capacity compared to un-coated amine sorbents. The cost of the solid amine sorbent developed in this project is estimated to be less than $7.00/lb; the sorbent exhibited CO2 capture capacity more than 2.3 mmol/g. The results of this study provided the scientific basis for further development of SO2-resistant sorbents.

  12. [TDA`s hot gas desulfurization sorbent]. TDA Inc./FETC CRADA No. 97-F003, final report

    SciTech Connect

    Berry, D.A.

    1997-11-14

    This report describes the results of a Cooperative Research and Development Agreement (CRADA) between TDA Incorporated and the Federal Energy Technology Center (FETC) in Morgantown, West Virginia. The objective of this CRADA was to evaluate the performance of TDA`s hot gas desulfurization (HGD) sorbent for use in fossil fuel gasification processes. This particular sorbent, TNT-MB was developed for use in moving-bed HGD reactors in an integrated gasification combined cycle (IGCC) power plant. Two separate tests were conducted; a 10-cycle test, and a low-temperature scoping test. All 10 cycles absorbed H{sub 2}S for the prescribed 125 minutes without breakthrough. The H{sub 2}S concentration remained below 50 ppmv throughout the 125 minute test period. The sorbent showed an increase in attrition resistance from 1.8% (fresh) to 0.87% (reactor inlet) and 0.64% (reactor outlet) after 10 cycles. The results of an additional attrition test are also contained in this report.

  13. High temperature sorbents for oxygen

    NASA Technical Reports Server (NTRS)

    Sharma, Pramod K. (Inventor)

    1994-01-01

    A sorbent capable of removing trace amounts of oxygen (ppt) from a gas stream at a high temperature above 200 C comprising a porous alumina silicate support, such as zeolite, containing from 1 to 10 percent by weight of ion exchanged transition metal, such as copper or cobalt ions, and 0.05 to 1.0 percent by weight of an activator selected from a platinum group metal such as platinum is described. The activation temperature, oxygen sorption, and reducibility are all improved by the presence of the platinum activator.

  14. MERCURIC CHLORIDE CAPTURE BY ALKALINE SORBENTS

    EPA Science Inventory

    The paper gives results of bench-scale mechanistic studies of mercury/sorbent reactions that showed that mercuric chloride (HgC12) is readily adsorbed by alkaline sorbents, which may offers a less expensive alternative to the use of activated carbons. A laboratory-scale, fixed-b...

  15. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    SciTech Connect

    David A. Green; Brian S. Turk; Raghubir P. Gupta; William J. McMichael; Douglas P. Harrison; Ya Liang

    2002-01-01

    The objective of this project is to develop a simple, inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, or ''baking soda,'' through reaction with carbon dioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. This quarter, five cycle thermogravimetric tests were conducted at the Louisiana State University (LSU) with sodium bicarbonate Grade 3 (SBC{number_sign}3) which showed that carbonation activity declined slightly over 5 cycles following severe calcination conditions of 200 C in pure CO{sub 2}. Three different sets of calcination conditions were tested. Initial carbonation activity (as measured by extent of reaction in the first 25 minutes) was greatest subsequent to calcination at 120 C in He, slightly less subsequent to calcination in 80% CO{sub 2}/20% H{sub 2}O, and lowest subsequent to calcination in pure CO{sub 2} at 200 C. Differences in the extent of reaction after 150 minutes of carbonation, subsequent to calcination under the same conditions followed the same trend but were less significant. The differences between fractional carbonation under the three calcination conditions declined with increasing cycles. A preliminary fixed bed reactor test was also conducted at LSU. Following calcination, the sorbent removed approximately 19% of the CO{sub 2} in the simulated flue gas. CO{sub 2} evolved during subsequent calcination was consistent with an extent of carbonation of approximately 49%. Following successful testing of SBC{number_sign}3 sorbent at RTI reported in the last quarter, a two cycle fluidized bed reactor test was conducted with trona as the sorbent precursor, which was calcined to sodium carbonate. In the first carbonation cycle, CO

  16. Demonstration of Mercury Sorbents to Meet DOE Customer Needs

    SciTech Connect

    Klasson, K.T.

    2000-05-08

    Many sorbents have been developed for the removal of mercury and heavy metals from water; however, the majority of data published to date do not address the removal of mercury to the target levels represented in this project. The application for which these sorbents were targeted for use was the removal of mercury from microgram-per-liter levels to low nanogram-per-liter levels. Overall, the thiol-based resins had the best performance when removing low concentrations of mercury in water at two U.S. Department of Energy facilities in field experiments. It was difficult to achieve the targeted low nanogram-per-liter levels at both sites; however, a substantial amount of mercury was removed by the resins. This is attributed to the mercury speciation, since filtration tests have shown that a significant portion of the mercury at each test location is particle bound or associated with particulate and colloidal matter. The engineered Self-Assembled Mercaptan on Mesoporous Silica (SAMMS) material proved to be as effective as some of the commercial sorbents in removing mercury at the Nonradiological Wastewater Treatment Plant (NRWTP) at Oak Ridge National Laboratory. The material performed almost as well as some of the best sorbents at the Upper East Fork Poplar Creek site at the Oak Ridge Y-12 Plant. The most effective sorbents were SAMMS; Keyle:X, by SolmeteX, Inc.; and SIR-200, by ResinTech, Inc. It was also found that the Keyle:X performed better at the NRWTP when the water was pretreated with hypochlorite to oxidize some mercury species. Because of the scattering of data, mathematical modeling was limited to predicting the behavior of active mercury. Since the field samples contained a substantial amount of particle-bound mercury, the mathematical models did not represent the field data very well. Nevertheless, it was useful to predict the performance of these sorbents at very low concentrations of mercury. Mathematical modeling was also used to investigate the

  17. Theoretical calculating the thermodynamic properties of solid sorbents for CO{sub 2} capture applications

    SciTech Connect

    Duan, Yuhua

    2012-11-02

    Since current technologies for capturing CO{sub 2} to fight global climate change are still too energy intensive, there is a critical need for development of new materials that can capture CO{sub 2} reversibly with acceptable energy costs. Accordingly, solid sorbents have been proposed to be used for CO{sub 2} capture applications through a reversible chemical transformation. By combining thermodynamic database mining with first principles density functional theory and phonon lattice dynamics calculations, a theoretical screening methodology to identify the most promising CO{sub 2} sorbent candidates from the vast array of possible solid materials has been proposed and validated. The calculated thermodynamic properties of different classes of solid materials versus temperature and pressure changes were further used to evaluate the equilibrium properties for the CO{sub 2} adsorption/desorption cycles. According to the requirements imposed by the pre- and post- combustion technologies and based on our calculated thermodynamic properties for the CO{sub 2} capture reactions by the solids of interest, we were able to screen only those solid materials for which lower capture energy costs are expected at the desired pressure and temperature conditions. Only those selected CO{sub 2} sorbent candidates were further considered for experimental validations. The ab initio thermodynamic technique has the advantage of identifying thermodynamic properties of CO{sub 2} capture reactions without any experimental input beyond crystallographic structural information of the solid phases involved. Such methodology not only can be used to search for good candidates from existing database of solid materials, but also can provide some guidelines for synthesis new materials. In this presentation, we first introduce our screening methodology and the results on a testing set of solids with known thermodynamic properties to validate our methodology. Then, by applying our computational method

  18. Theoretical Screening of Mixed Solid Sorbent for Applications to CO{sub 2} Capture Technology

    SciTech Connect

    Duan, Yuhua

    2014-03-30

    Since current technologies for capturing CO{sub 2} to fight global climate change are still too energy intensive, there is a critical need for development of new materials that can capture CO{sub 2} reversibly with acceptable energy costs. Accordingly, solid sorbents have been proposed to be used for CO{sub 2} capture applications through a reversible chemical transformation. By combining thermodynamic database mining with first principles density functional theory and phonon lattice dynamics calculations, a theoretical screening methodology to identify the most promising CO{sub 2} sorbent candidates from the vast array of possible solid materials has been proposed and validated. The calculated thermodynamic properties of different classes of solid materials versus temperature and pressure changes were further used to evaluate the equilibrium properties for the CO{sub 2} adsorption/desorption cycles. According to the requirements imposed by the pre- and post- combustion technologies and based on our calculated thermodynamic properties for the CO{sub 2} capture reactions by the solids of interest, we were able to screen only those solid materials for which lower capture energy costs are expected at the desired pressure and temperature conditions. Only those selected CO{sub 2} sorbent candidates were further considered for experimental validations. The ab initio thermodynamic technique has the advantage of identifying thermodynamic properties of CO{sub 2} capture reactions without any experimental input beyond crystallographic structural information of the solid phases involved. Such methodology not only can be used to search for good candidates from existing database of solid materials, but also can provide some guidelines for synthesis new materials. In this presentation, we apply our screening methodology to mixing solid systems to adjust the turnover temperature to help on developing CO{sub 2} capture Technologies.

  19. Theoretical Screening of Mixed Solid Sorbent for Applications to CO2 Capture Technology

    SciTech Connect

    Duan, Yuhua

    2014-01-01

    Since current technologies for capturing CO2 to fight global climate change are still too energy intensive, there is a critical need for development of new materials that can capture CO2 reversibly with acceptable energy costs. Accordingly, solid sorbents have been proposed to be used for CO2 capture applications through a reversible chemical transformation. By combining thermodynamic database mining with first principles density functional theory and phonon lattice dynamics calculations, a theoretical screening methodology to identify the most promising CO2 sorbent candidates from the vast array of possible solid materials has been proposed and validated. The calculated thermodynamic properties of different classes of solid materials versus temperature and pressure changes were further used to evaluate the equilibrium properties for the CO2 adsorption/desorption cycles. According to the requirements imposed by the pre- and post- combustion technologies and based on our calculated thermodynamic properties for the CO2 capture reactions by the solids of interest, we were able to screen only those solid materials for which lower capture energy costs are expected at the desired pressure and temperature conditions. Only those selected CO2 sorbent candidates were further considered for experimental validations. The ab initio thermodynamic technique has the advantage of identifying thermodynamic properties of CO2 capture reactions without any experimental input beyond crystallographic structural information of the solid phases involved. Such methodology not only can be used to search for good candidates from existing database of solid materials, but also can provide some guidelines for synthesis new materials. In this presentation, we apply our screening methodology to mixing solid systems to adjust the turnover temperature to help on developing CO2 capture Technologies.

  20. Computational Modeling of Mixed Solids for CO2 CaptureSorbents

    SciTech Connect

    Duan, Yuhua

    2015-01-01

    Since current technologies for capturing CO2 to fight global climate change are still too energy intensive, there is a critical need for development of new materials that can capture CO2 reversibly with acceptable energy costs. Accordingly, solid sorbents have been proposed to be used for CO2 capture applications through a reversible chemical transformation. By combining thermodynamic database mining with first principles density functional theory and phonon lattice dynamics calculations, a theoretical screening methodology to identify the most promising CO2 sorbent candidates from the vast array of possible solid materials has been proposed and validated. The calculated thermodynamic properties of different classes of solid materials versus temperature and pressure changes were further used to evaluate the equilibrium properties for the CO2 adsorption/desorption cycles. According to the requirements imposed by the pre- and post- combustion technologies and based on our calculated thermodynamic properties for the CO2 capture reactions by the solids of interest, we were able to screen only those solid materials for which lower capture energy costs are expected at the desired pressure and temperature conditions. Only those selected CO2 sorbent candidates were further considered for experimental validations. The ab initio thermodynamic technique has the advantage of identifying thermodynamic properties of CO2 capture reactions without any experimental input beyond crystallographic structural information of the solid phases involved. Such methodology not only can be used to search for good candidates from existing database of solid materials, but also can provide some guidelines for synthesis new materials. In this presentation, we apply our screening methodology to mixing solid systems to adjust the turnover temperature to help on developing CO2 capture Technologies.

  1. Recovery evaluation of organophosphorus pesticides from bee pollen by matrix solid-phase dispersion extraction using sorbents based on silica and titania

    NASA Astrophysics Data System (ADS)

    Torres-Perea, C.; Muñoz-Rodríguez, D.; Medina-Peralta, S.; Carrera-Figueiras, C.; Moguel-Ordóñez, Y. B.

    2013-06-01

    This work focused on the evaluation of the recovery of organophosphorus pesticides from bee pollen after matrix solid phase-dispersion extraction (MSPD). Materials based on silica, titania and titania modified with polivylnylimidazole or polyestirene were used as adsorbents for the extraction of pesticides. Small amounts of fortified pollen (0.1 g, at 1 micro-g/g of pesticides), adsorbent (0.4 g) and solvent elution (1 mL de acetonitrile - ACN) were used in the extractions. For recovery evaluation, pollen extracts were analyzed by gas chromatography coupled with mass spectrometry.

  2. Evaluation of a new carbon/zirconia-based sorbent for cleanup of food extracts in multiclass analysis of pesticides and environmental contaminants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A novel carbon/zirconia based material, SupelTM QuE Verde (Verde), was evaluated in a filter-vial dispersive solid phase extraction (d-SPE) cleanup of QuEChERS extracts of pork, salmon, kale, and avocado for residual analysis of pesticides and environmental contaminants. Low pressure (LP) GC-MS/MS w...

  3. Synthesis of a molecularly imprinted sorbent for selective solid-phase extraction of β-N-methylamino-L-alanine.

    PubMed

    Svoboda, Pavel; Combes, Audrey; Petit, Julia; Nováková, Lucie; Pichon, Valérie

    2015-11-01

    The aim of the work was to synthesize a molecularly imprinted material for the selective solid-phase extraction (SPE) of β-N-methylamino-L-alanine (L-2-amino-3-methylpropionic acid; BMAA) from cyanobacterial extracts. BMAA and its structural analogs that can be used as template are small, polar and hydrophilic molecules. These molecules are poorly soluble in organic solvents that are commonly used for the synthesis of acrylic-based polymers. Therefore, a sol gel approach was chosen to carry out the synthesis and the resulting sorbents were evaluated with different extraction procedures in order to determine their ability to selectively retain BMAA. The presence of imprinted cavities in the sorbent was demonstrated by comparing elution profiles obtained by using molecularly imprinted silica (MIS) and non-imprinted silica (NIS) as a control. The molecularly imprinted solid-phase extraction (MISPE) procedure was first developed in a pure medium (acetonitrile) and further optimized for the treatment of cyanobacterial samples. It was characterized by high elution recoveries (89% and 77% respectively in pure and in real media).The repeatability of the extraction procedure in pure medium, in real medium and the reproducibility of MIS synthesis all expressed as RSD values of extraction recovery of BMAA were equal to 3%, 12% and 5%, respectively. A MIS capacity of 0.34 µmol/g was measured. The matrix effects, which affected the quantification of BMAA when employing a mixed mode sorbent, were completely removed by adding a clean-up step of the mixed-mode sorbent extract on the MIS.

  4. Handling, transport and dispersion of sorbent powder for in-furnace injection. Final report, September 1, 1993--August 31, 1994

    SciTech Connect

    Fan, L.S.; Abou-Zeida, E.; Liang, S.C.; Luo, Xukun

    1995-02-01

    The focus of this project is on sorbent injection technologies using dry, calcium-based sorbents for high-sulfur coal flue gas desulfurization. The goal is to provide research findings on handling, transport and dispersion of sorbent powder, aimed at improving SO{sub 2} (to at least 90%) removal and increasing sorbent utilization in a cost-effective fashion. The purpose of this project is to investigate the fundamental aspects of powder technology relevant to the fine sorbent powders, and to provide means of improving sorbent performance through superior dispersion and reduced dispersed particle size. This project is in two phases, Phase 1 ``Powder Characterization`` and Phase 2 ``Powder Mechanical Properties``. Phase 1 involves characterization of the sorbents in terms of their electrostatic properties. The triboelectric charging of powders are studied in detail by measuring sorbent charging as a function of material properties as well as transport conditions. A variety of sorbents are tested, including laboratory-made lignohydrates, calcite, dolomite, dolomitic hydrate and hydrated lime. The effects of transport tube material and gas properties, specifically humidity and velocity on the extent of sorbent charging are also investigated. A population balance model is developed to account for the particle size distribution for powder dispersion through gas-solid injection nozzles. The variations of the transition probability with the booster air velocities is examined. Simulation of particle size distributions under some operating conditions is conducted. Phase 2 investigates the flow properties of several calcium-based sorbents under different handling and transporting conditions. Effect of moisture content, as an important handling condition, on these properties is examined. Determined properties has been analyzed to study their effect on the transport and handling processes.

  5. Investigation and Demonstration of Dry Carbon-Based Sorbent Injection for Mercury Control

    SciTech Connect

    Jim Butz; Terry Hunt

    2005-11-01

    Public Service Company of Colorado and ADA Technologies, Inc. have performed a study of the injection of activated carbon for the removal of vapor-phase mercury from coal-fired flue gas streams. The project was completed under contract to the US Department of Energy's National Energy Technology Laboratory, with contributions from EPRI and Public Service Company. The prime contractor for the project was Public Service Company, with ADA Technologies as the major subcontractor providing technical support to all aspects of the project. The research and development effort was conducted in two phases. In Phase I a pilot facility was fabricated and tests were performed using dry carbon-based sorbent injection for mercury control on a coal-fired flue gas slipstream extracted from an operating power plant. Phase II was designed to move carbon injection technology towards commercial application on coal-fired power plants by addressing key reliability and operability concerns. Phase II field work included further development work with the Phase I pilot and mercury measurements on several of PSCo's coal-fired generating units. In addition, tests were run on collected sorbent plus fly ash to evaluate the impact of the activated carbon sorbent on the disposal of fly ash. An economic analysis was performed where pilot plant test data was used to develop a model to predict estimated costs of mercury removal from plants burning western coals. Testing in the pilot plant was undertaken to quantify the effects of plant configuration, flue gas temperature, and activated carbon injection rate on mercury removal. All three variables were found to significantly impact the mercury removal efficiency in the pilot. The trends were clear: mercury removal rates increased with decreasing flue gas temperature and with increasing carbon injection rates. Mercury removal was much more efficient with reverse-gas and pulse-jet baghouse configurations than with an ESP as the particulate control device

  6. EVALUATION OF INTERNALLY STAGED COAL BURNERS AND SORBENT JET AERODYNAMICS FOR COMBINED SO2/NOX CONTROL IN UTILITY BOILERS; VOLUME 2. TESTING IN A 100 MILLION BTU/HR EXPERIMENTAL FURNACE

    EPA Science Inventory

    The report givesresults of100 million Btu/hr (29 MWt) experimental furnace to explore methods for achieving effective S02 removal in a coalfired utility boiler using calcium-based sorbents, through appropriate selection of injection location and injector design/operating paramete...

  7. EVALUATION OF INTERNALLY STAGED COAL BURNERS AND SORBENT JET AERODYNAMICS FOR COMBINED SO2/NOX CONTROL IN UTILITY BOILERS, VOLUME 1, TESTING IN A 10 MILLION BTU/HR EXPERIMENTAL FURNACE

    EPA Science Inventory

    The document gives results of tests conducted in a 2 MWt experimental furnace to: (1) investigate ways to reduce NOx emissions from utility coal burners without external air ports (i.e., with internal fuel/air staging); and (2) improve the performance of calcium-based sorbents fo...

  8. Performance of Amine-Multilayered Solid Sorbents for CO{sub 2} Removal: Effect of Fabrication Variables

    SciTech Connect

    Jiang, Bingbing; Kish, Vincent; Li, Bingyun; Fauth, Daniel J; Gray, McMahan L; Pennline, Henry W; Richards, George A.

    2011-09-01

    The emission of fossil fuel carbon dioxide (CO{sub 2) to the atmosphere is implicated as the predominant cause of global climate change; therefore, advanced CO{sub 2} capture technologies are of the utmost importance. In this study, innovative amine-multilayered sorbents were fabricated using layer-by-layer (LbL) nanoassembly technology via alternate deposition of a CO{sub 2}-adsorbing amine polymer (e.g. polyethylenimine or PEI) and an oppositely-charged polymer (e.g. polystyrene sulfonate or PSS). We found that the developed sorbents could be used for CO{sub 2} capture and that LbL nanoassembly allows us to engineer their CO{sub 2} capture performance through the fabrication variables (e.g. deposition polymers, deposition media, and number of bilayers). PEI/PSS was found to be the best polymer combination for developing sorbents with relatively high CO{sub 2} capture capacity. The amine-multilayered solid sorbents possessed fine microstructures and may have similar polymer deposition within and on the surface of solid sorbents. These amine-multilayered sorbents had much faster CO{sub 2} desorption rates compared to sorbents prepared using the current PEI-impregnation approach. Such fast CO{sub 2} desorption could make sorbents a good option for CO{sub 2} removal from power plants and even the atmosphere.

  9. Hot Coal Gas Desulfurization with manganese-based sorbents. Second [quarterly] technical report, December 1, 1992--March 1, 1993

    SciTech Connect

    Hepworth, M.T.

    1993-03-01

    At present, the focus of work being performed on Hot Coal Gas Desulfurization is primarily in the use of zinc ferrite and zinc titanate sorbents; however studies at the US Steel Fundamental Research Laboratories in Monroeville, PA, by E. T. Turkdogan indicate that an alternate sorbent, manganese dioxide-containing ore in mixture with alumina (75 wt % ore + 25 wt % Al{sub 2}O{sub 3}) may be a preferable alternative to zinc-based sorbents. A significant domestic source of manganese in Minnesota is being explored for an in situ leach process which has potential for producing large tonnages of solutions which may be ideal for precipitation and recovery of pure manganese as a carbonate in a reactive form. In the current program the following studies will be addressed: Preparation of manganese sorbent pellets and characterization tests on pellets for strength and surface area; analysis of the thermodynamics and kinetics of sulfur removal from hot fuel gases by individual sorbent pellets (loading tests) by thermogravimetric testing; regeneration tests via TGA on individual sorbent pellets by oxidation; and bench-scale testing on sorbent beds in a two-inch diameter reactor. The developed information will be of value to METC in its determination of whether or not a manganese-based regenerable sorbent holds real promise for sulfur cleanup of hot fuel gases. This information is necessary prior to pilot-scale testing leading to commercial development is undertaken.

  10. Sorbents for the oxidation and removal of mercury

    DOEpatents

    Olson, Edwin S; Holmes, Michael J; Pavlish, John Henry

    2013-08-20

    A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

  11. Sorbents for the oxidation and removal of mercury

    DOEpatents

    Olson, Edwin S.; Holmes, Michael J.; Pavlish, John Henry

    2014-09-02

    A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

  12. Sorbents for the oxidation and removal of mercury

    DOEpatents

    Olson, Edwin S.; Holmes, Michael J.; Pavlish, John H.

    2012-05-01

    A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

  13. Sorbents for the oxidation and removal of mercury

    DOEpatents

    Olson, Edwin S.; Holmes, Michael J.; Pavlish, John H.

    2008-10-14

    A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

  14. A regenerable sorbent injection/filtration process for H{sub 2}S removal from hot gas

    SciTech Connect

    Higgins, R.J.; Ji, W.; Connors, M.J.; Jones, J.F.; Goldsmith, R.L.

    1996-12-31

    The operational characteristics of a hot gas desulfurization process involving regenerable sorbent injection and its subsequent collection with a ceramic filtration device were studied utilizing a bench-scale transport reactor. Hydrogen sulfide removal from simulated hot gas was evaluated as a function of both zinc oxide-based sorbent physical and chemical characteristics and various process parameters. In addition, the sorbent capture efficiency and regenerability of the ceramic filtration device were evaluated, and regeneration of sulfided sorbents via injection into an oxidizing gas was studied. For both sorbent sulfidation and spent sorbent regeneration, gas-solid reaction occurred both in the duct and within layers of partially reacted sorbent captured by the ceramic filter. Very high sulfur removal efficiencies were obtained only in highly reducing hot gas compositions at or above about 700 C, using stoichiometric ratio (defined as ZnO/H{sub 2}S ratio) values of about 1.5, and sorbent particles of about 20 {micro}m or less in diameter. Under such conditions, the experimental data indicated that reaction of H{sub 2}S with zinc vapor formed by reduction of zinc oxide contributed appreciably to sulfur removal. Negligible zinc loss from the hot zone of the reactor was detected, apparently due to rapid formation of zinc sulfide product layers on zinc oxide particles. The ceramic filtration devices captured 100% of all sorbent particles and were fully regenerable over periods of several tens of injection/backpulse cleaning cycles. Spent sorbent could be fully regenerated rapidly at 850 C without problems due to exotherm generation.

  15. Can Economic Development Programs Be Evaluated?

    ERIC Educational Resources Information Center

    Bartik, Timothy J.; Bingham, Richard D.

    The question of whether economic development programs can be evaluated seems simple, but the answer is not simple because of the nature of evaluation. Determining a program's effectiveness requires the evaluator to distinguish changes due to the program from changes due to nonprogram factors. The evaluator must focus on outcomes caused by the…

  16. Developing and Implementing a Counselor Evaluation Program.

    ERIC Educational Resources Information Center

    Bell, Priscilla J.; Acker, Kathleen E.

    In the past several years, Tacoma Community College (TCC) has devoted increasing attention to evaluating faculty and staff performance. In recognition of the benefits of a growth-oriented evaluation process over a summative evaluation, the counselors and the Dean for Student Services at TCC developed a comprehensive evaluation system for…

  17. Telehealth success: evaluation framework development.

    PubMed

    Hebert, M

    2001-01-01

    Implementing telehealth applications represents a substantial investment of resources, which is one reason why success is of great interest. Many research and evaluation studies have investigated measures of successful telehealth systems. However, the term "telehealth" represents a wide range of variables including clinical application, characteristics of the information being transmitted, temporal relationships of data transfer and the organizational context. These sources of variability pose many challenges for evaluation as well as for building a cumulative history of research. A conceptual framework is required that assists in categorizing results and drawing conclusions based on an accumulation of findings. One measure of "success" in health care is quality patient care and this reflects a primary reason for ICT investments. For this reason, Donabedian's work in evaluating quality provides the basis for the proposed framework. DeLone and McLean's definitions of IS success assist in conceptualizing Donabedian's structure-outcome-process variables in a telehealth context. Multiple evaluation approaches have been used to address different types of questions. Prior to the technologies being introduced to clinical care, there are usually many studies to demonstrate their effectiveness. Health Technology Assessment examines a broader context than the technology alone, including costs and comparing alternatives that would exist in the absence of telehealth. It considers performance measures; outcomes; summary measures, operational considerations, and other issues. Program Evaluation examines use of the technology to provide a service or deliver a program. Evaluation questions often address whether the program goals have been met and if it is operating as expected. Perhaps of greater concern than the evaluation approach taken is generalizability of findings. Recent studies have given inadequate attention to defining what is done (i.e. comparison of telehealth to most

  18. Carbon Dioxide Capture from Flue Gas Using Dry Regenerable Sorbents

    SciTech Connect

    Thomas Nelson; David Green; Paul Box; Raghubir Gupta; Gennar Henningsen

    2007-06-30

    Regenerable sorbents based on sodium carbonate (Na{sub 2}CO{sub 3}) can be used to separate carbon dioxide (CO{sub 2}) from coal-fired power plant flue gas. Upon thermal regeneration and condensation of water vapor, CO{sub 2} is released in a concentrated form that is suitable for reuse or sequestration. During the research project described in this report, the technical feasibility and economic viability of a thermal-swing CO{sub 2} separation process based on dry, regenerable, carbonate sorbents was confirmed. This process was designated as RTI's Dry Carbonate Process. RTI tested the Dry Carbonate Process through various research phases including thermogravimetric analysis (TGA); bench-scale fixed-bed, bench-scale fluidized-bed, bench-scale co-current downflow reactor testing; pilot-scale entrained-bed testing; and bench-scale demonstration testing with actual coal-fired flue gas. All phases of testing showed the feasibility of the process to capture greater than 90% of the CO{sub 2} present in coal-fired flue gas. Attrition-resistant sorbents were developed, and these sorbents were found to retain their CO{sub 2} removal activity through multiple cycles of adsorption and regeneration. The sodium carbonate-based sorbents developed by RTI react with CO{sub 2} and water vapor at temperatures below 80 C to form sodium bicarbonate (NaHCO3) and/or Wegscheider's salt. This reaction is reversed at temperatures greater than 120 C to release an equimolar mixture of CO{sub 2} and water vapor. After condensation of the water, a pure CO{sub 2} stream can be obtained. TGA testing showed that the Na{sub 2}CO3 sorbents react irreversibly with sulfur dioxide (SO{sub 2}) and hydrogen chloride (HCl) (at the operating conditions for this process). Trace levels of these contaminants are expected to be present in desulfurized flue gas. The sorbents did not collect detectable quantities of mercury (Hg). A process was designed for the Na{sub 2}CO{sub 3}-based sorbent that includes a co

  19. Effect of precursor and preparation method on manganese based activated carbon sorbents for removing H2S from hot coal gas.

    PubMed

    Wang, Jiancheng; Qiu, Biao; Han, Lina; Feng, Gang; Hu, Yongfeng; Chang, Liping; Bao, Weiren

    2012-04-30

    Activated carbon (AC) supported manganese oxide sorbents were prepared by the supercritical water impregnation (SCWI) using two different precursor of Mn(NO(3))(2) (SCW(N)) and Mn(Ac)(2)·4H(2)O (SCW(A)). Their capacities of removing H(2)S from coal gas were evaluated and compared to the sorbents prepared by the pore volume impregnation (PVI) method. The structure and composition of different sorbents were characterized by XRD, SEM, TEM, XPS and XANES techniques. It is found that the precursor of active component plays the crucial role and SCW(N) sorbents show much better sulfidation performance than the SCW(A) sorbents. This is because the Mn(3)O(4) active phase of the SCW(N) sorbents are well dispersed on the AC support, while the Mn(2)SiO(4)-like species in the SCW(A) sorbent can be formed and seriously aggregated. The SCW(N) sorbents with 2.80% and 5.60% manganese are favorable for the sulfidation reaction, since the Mn species are better dispersed on the SCW(N) sorbents than those on the PV(N) sorbents and results in the better sulfidation performance of the SCW(N) sorbents. As the Mn content increases to 11.20%, the metal oxide particles on AC supports aggregate seriously, which leads to poorer sulfidation performance of the SCW(N)11.20% sorbents than that of the PV(N)11.20% sorbents. PMID:22341981

  20. Sorption of methylxanthines by different sorbents

    NASA Astrophysics Data System (ADS)

    Dmitrienko, S. G.; Andreeva, E. Yu.; Tolmacheva, V. V.; Terent'eva, E. A.

    2013-05-01

    Sorption of caffeine, theophylline, theobromine, diprophylline, and pentoxyphylline on different sorbents (supercross-linked polystyrene, surface-modified copolymer of styrene and divinylbenzene Strata-X, and carbon nanomaterials Taunit and Diasorb-100-C16T) was studied in a static mode in an effort to find new sorbents suitable for sorption isolation and concentration of methylxanthines. The peculiarities of sorption of methylxanthines were explained in relation to the solution acidity, the nature of the sorbates and their concentration, the nature of the solvent, and the structural characteristics of the sorbents.

  1. Development of an analytical method coupling cell membrane chromatography with gas chromatography-mass spectrometry via microextraction by packed sorbent and its application in the screening of volatile active compounds in natural products.

    PubMed

    Li, Miao; Wang, Sicen; He, Langchong

    2015-01-01

    Natural products (NPs) are important sources of lead compounds in modern drug discovery. To facilitate the screening of volatile active compounds in NPs, we have developed a new biochromatography method that uses rat vascular smooth muscle cells (VSMC), which are rich in L-type calcium channels (LCC), to prepare the stationary phase. This integrated method, which couples cell membrane chromatography (CMC) with gas chromatography-mass spectrometry (GC-MS) via microextraction by packed sorbent (MEPS) technology, has been termed VSMC/CMC-MEPS-GC-MS. Methodological validation confirmed its specificity, reliability and convenience. Screening results for Radix Angelicae Dahuricae and Fructus Cnidii obtained using VSMC/CMC-MEPS-GC-MS were consistent with those obtained using VSMC/CMC-offline-GC-MS. MEPS connection plays as simplified solid-phase extraction and replaces the uncontrollable evaporation operation in reported offline connections, so our new method is supposed to be more efficient and reliable than the offline ones, especially for compounds that are volatile, thermally unstable or difficult to purify. In application, senkyunolide A and ligustilide were preliminary identified as the volatile active components in Rhizoma Chuanxiong. We have thus confirmed the suitability of VSMC/CMC-MEPS-GC-MS for volatile active compounds screening in NP.

  2. Development of an analytical method coupling cell membrane chromatography with gas chromatography-mass spectrometry via microextraction by packed sorbent and its application in the screening of volatile active compounds in natural products.

    PubMed

    Li, Miao; Wang, Sicen; He, Langchong

    2015-01-01

    Natural products (NPs) are important sources of lead compounds in modern drug discovery. To facilitate the screening of volatile active compounds in NPs, we have developed a new biochromatography method that uses rat vascular smooth muscle cells (VSMC), which are rich in L-type calcium channels (LCC), to prepare the stationary phase. This integrated method, which couples cell membrane chromatography (CMC) with gas chromatography-mass spectrometry (GC-MS) via microextraction by packed sorbent (MEPS) technology, has been termed VSMC/CMC-MEPS-GC-MS. Methodological validation confirmed its specificity, reliability and convenience. Screening results for Radix Angelicae Dahuricae and Fructus Cnidii obtained using VSMC/CMC-MEPS-GC-MS were consistent with those obtained using VSMC/CMC-offline-GC-MS. MEPS connection plays as simplified solid-phase extraction and replaces the uncontrollable evaporation operation in reported offline connections, so our new method is supposed to be more efficient and reliable than the offline ones, especially for compounds that are volatile, thermally unstable or difficult to purify. In application, senkyunolide A and ligustilide were preliminary identified as the volatile active components in Rhizoma Chuanxiong. We have thus confirmed the suitability of VSMC/CMC-MEPS-GC-MS for volatile active compounds screening in NP. PMID:25463192

  3. The Design, Development, and Evaluation of an Evaluative Computer Simulation.

    ERIC Educational Resources Information Center

    Ehrlich, Lisa R.

    This paper discusses evaluation design considerations for a computer based evaluation simulation developed at the University of Iowa College of Medicine in Cardiology to assess the diagnostic skills of primary care physicians and medical students. The simulation developed allows for the assessment of diagnostic skills of physicians in the…

  4. Studies of in-situ calcium-based sorbents in advanced pressurized coal conversion systems

    SciTech Connect

    Katta, S.; Shires, P.J.; O'Donnell, J.J.

    1992-01-01

    The overall objective of the project is to obtain experimental data on the reactions of calcium-based sorbents in gasification systems and to evaluate or develop kinetic models applicable to the commercial design of such systems. Both air-blown coal gasification systems and second generation fluid bed combustion systems (partial gasification) will be investigated, as well as subsequent stabilization of the solid wastes (calcium sulfide/ash) produced. More specifically, the objectives are to: Develop data on kinetics of in-situ desulfurization reactions; study the effect of calcium on the kinetics of carbon conversion rate; study kinetics of oxidation of CaS to CaSO[sup 4]; Develop and identify viable techniques to stabilize CaS; and, carry out further development work on most promising method and determine its commercial economics.

  5. Studies of in-situ calcium-based sorbents in advanced pressurized coal conversion systems

    SciTech Connect

    Katta, S.; Shires, P.J.; O`Donnell, J.J.

    1992-11-01

    The overall objective of the project is to obtain experimental data on the reactions of calcium-based sorbents in gasification systems and to evaluate or develop kinetic models applicable to the commercial design of such systems. Both air-blown coal gasification systems and second generation fluid bed combustion systems (partial gasification) will be investigated, as well as subsequent stabilization of the solid wastes (calcium sulfide/ash) produced. More specifically, the objectives are to: Develop data on kinetics of in-situ desulfurization reactions; study the effect of calcium on the kinetics of carbon conversion rate; study kinetics of oxidation of CaS to CaSO{sup 4}; Develop and identify viable techniques to stabilize CaS; and, carry out further development work on most promising method and determine its commercial economics.

  6. Pilot plant tests of Z-Sorb{trademark} sorbent

    SciTech Connect

    Greenwood, G.J.; Khare, G.P.; Kubicek, D.H.; Delzer, G.A.; Kinsinger, D.L.

    1995-06-01

    The objective of this work is to determine the long-term chemical reactivity and mechanical durability of Phillips Petroleum Company`s (PPCo`s) proprietary Z-Sorb{trademark} sorbent. Materials developed for fixed-, moving- and fluid bed desulfurization of coal derived gases at high pressure (5-20 atm) and moderate operating temperatures (600-1000{degrees}F) will be discussed.

  7. Novel Sorbent-Based Process for High Temperature Trace Metal Removal

    SciTech Connect

    Gokhan Alptekin

    2008-09-30

    The objective of this project was to demonstrate the efficacy of a novel sorbent can effectively remove trace metal contaminants (Hg, As, Se and Cd) from actual coal-derived synthesis gas streams at high temperature (above the dew point of the gas). The performance of TDA's sorbent has been evaluated in several field demonstrations using synthesis gas generated by laboratory and pilot-scale coal gasifiers in a state-of-the-art test skid that houses the absorbent and all auxiliary equipment for monitoring and data logging of critical operating parameters. The test skid was originally designed to treat 10,000 SCFH gas at 250 psig and 350 C, however, because of the limited gas handling capabilities of the test sites, the capacity was downsized to 500 SCFH gas flow. As part of the test program, we carried out four demonstrations at two different sites using the synthesis gas generated by the gasification of various lignites and a bituminous coal. Two of these tests were conducted at the Power Systems Demonstration Facility (PSDF) in Wilsonville, Alabama; a Falkirk (North Dakota) lignite and a high sodium lignite (the PSDF operator Southern Company did not disclose the source of this lignite) were used as the feedstock. We also carried out two other demonstrations in collaboration with the University of North Dakota Energy Environmental Research Center (UNDEERC) using synthesis gas slipstreams generated by the gasification of Sufco (Utah) bituminous coal and Oak Hills (Texas) lignite. In the PSDF tests, we showed successful operation of the test system at the conditions of interest and showed the efficacy of sorbent in removing the mercury from synthesis gas. In Test Campaign No.1, TDA sorbent reduced Hg concentration of the synthesis gas to less than 5 {micro}g/m{sup 3} and achieved over 99% Hg removal efficiency for the entire test duration. Unfortunately, due to the relatively low concentration of the trace metals in the lignite feed and as a result of the

  8. Developing an English Language Textbook Evaluation Checklist

    ERIC Educational Resources Information Center

    Mukundan, Jayakaran; Hajimohammadi, Reza; Nimehchisalem, Vahid

    2011-01-01

    The paper describes the considerations that were taken into account in the development of a tentative English language textbook evaluation checklist. A brief review of the related literature precedes the crucial issues that should be considered in developing checklists. In the light of the previous evaluation checklists the developers created a…

  9. Highly Attrition Resistant Zinc Oxide-Based Sorbents for H2S Removal by Spray Drying Technique

    SciTech Connect

    Ryu, C.K.; Lee, J.B.; Ahn, D.H.; Kim, J.J.; Yi, C.K.

    2002-09-19

    Primary issues for the fluidized-bed/transport reactor process are high attrition resistant sorbent, its high sorption capacity and regenerability, durability, and cost. The overall objective of this project is the development of a superior attrition resistant zinc oxide-based sorbent for hot gas cleanup in integrated coal gasification combined cycle (IGCC). Sorbents applicable to a fluidized-bed hot gas desulfurization process must have a high attrition resistance to withstand the fast solid circulation between a desulfurizer and a regenerator, fast kinetic reactions, and high sulfur sorption capacity. The oxidative regeneration of zinc-based sorbent usually initiated at greater than 600 C with highly exothermic nature causing deactivation of sorbent as well as complication of sulfidation process by side reaction. Focusing on solving the sorbent attrition and regenerability of zinc oxide-based sorbent, we have adapted multi-binder matrices and direct incorporation of regeneration promoter. The sorbent forming was done with a spray drying technique that is easily scalable to commercial quantity.

  10. A Hybrid Evaluation Model for Evaluating Online Professional Development

    ERIC Educational Resources Information Center

    Hahs-Vaughn, Debbie; Zygouris-Coe, Vicky; Fiedler, Rebecca

    2007-01-01

    Online professional development is multidimensional. It encompasses: a) an online, web-based format; b) professional development; and most likely c) specific objectives tailored to and created for the respective online professional development course. Evaluating online professional development is therefore also multidimensional and as such both…

  11. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report 4, July--September 1987

    SciTech Connect

    Jha, M.C.; Berggren, M.H.

    1987-10-27

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for improving the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hog coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. The reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point in a bench-scale fixed-bed reactor. The durability may be defined as the ability of the sorbent to maintain its reactivity and other important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and regeneration. Two base case sorbents, spherical pellets and cylindrical extrudes used in related METC sponsored projects, are being used to provide a basis for the comparison of physical characteristics and chemical reactivity.

  12. ASSESSMENT OF LOW COST NOVEL SORBENTS FOR COAL-FIRED POWER PLANT MERCURY CONTROL

    SciTech Connect

    Trevor Ley

    2003-07-01

    This is a Technical Report under a program funded by the Department of Energy's National Energy Technology Laboratory (NETL) to obtain the necessary information to assess the viability of lower cost alternatives to commercially available activated carbon for mercury control in coal-fired utilities. During this reporting period, ongoing tests and analysis on samples from Powerton and Valley to yield waste characterization results for the COHPAC long-term tests were conducted. A draft final report for the sorbent evaluations at Powerton was submitted. Sorbent evaluations at Valley Power Plant were completed on April 24, 2003. Data analysis and reporting for the Valley evaluations are continuing. A statement of work for sorbent evaluations at We Energies' Pleasant Prairie Power Plant was submitted and approved. Work will begin late August 2003. A no cost time extension was granted by DOE/NETL.

  13. Chemical sorbents: official guidelines and experimental approach.

    PubMed

    Fini, M; Spighi, M; Piva, D; Mongiorgi, R; Capelli, S; Nicoli Aldini, N; Giardino, R

    1993-11-01

    To evaluate the biocompatibility of an anionic exchange resin with active group trimethylammonium and charged with chloride ions an experimental study was performed with different tests to determine cytocompatibility, acute systemic toxicity, intracutaneous reactivity, allergic sensibilization, haemocompatibility and release of acetone, dichloromethane, quaternary amines and heavy metals (Pb, Cu, Cd) in eluate. Thus an anionic exchange resin can link all anionic substances; an ex vivo study on the participation of the dissociated sodic heparin in the anionic exchange was also conducted. In fact every time an extracorporeal circuit is made an anticoagulant must be administered to the patient and the removal of the drug could cause serious haemocoagulative problems. The results of the study showed a high biocompatibility of the resin that did not cause different significant reactions in comparison with negative control substances. The coating of the resin with poly-hydroxy-ethyl methacrilate with a separation phase technique avoided heparin removal from blood. Therefore adjustment of the dosage may not be necessary during further in vivo experiments. Future researches aiming to evaluate the the effectiveness and the biocompatibility of the sorbent in a living being will be performed in the next steps of the study. PMID:8060598

  14. Developing Peer Mentoring through Evaluation

    ERIC Educational Resources Information Center

    Hall, Ralph; Jaugietis, Zarni

    2011-01-01

    Peer mentoring programs are an important component in the strategy to enhance the first year undergraduate experience. The operation of these programs needs to be informed by evidence as to their effectiveness. In this article we report on a six-year study of the development of a peer mentoring program in which feedback is used to improve program…

  15. Kinetics of Mn-based sorbents for hot coal gas desulfurization. Quarterly progress report, March 15, 1995--July 15, 1995

    SciTech Connect

    Hepworth, M.T.

    1995-07-15

    Hot gas desulfurization may be accomplished by using solid sorbents such as oxides of those metals that form stable sulfides. The effectiveness of a desulfurizing agent in treating such gases is related to the predicted equilibrium partial pressure of hydrogen sulfide which will be present in a phase combination of the reduced form of sulfide and oxide phases. The focus of much current work being performed by the Department of Energy on sorbent development is in the use of zinc ferrite, zinc titanate, and Z-Sorb. The latter sorbent is a commercial product consisting of ZnO, a promoter, and a proprietary supporting matrix designed to provide stability and prolong sorbent life. Although these Zn-based sorbents have been the subject of extensive pilot-scale and process development work, all sorbents produced to date still experience structural and reactive degradation over multi-cycle use at relatively moderate temperatures. An effective alternative to zinc-based sorbents could be manganese sorbents which withstand high temperature operation and also maintain structural and reactive integrity over many cycles, as investigations by Ben-Slimane and Hepworth have indicated. Thermodynamic limits may prevent MnO from achieving the low sulfur specifications of the product gas for use in a molten carbonate fuel cell, but under the correct conditions the guideline for IGCC systems can easily be achieved. Furthermore, manganese sorbents could possibly be used in conjunction with a polishing sorbent (such as zinc oxide) possessing more favorable thermodynamic properties to reach levels acceptable for fuel cell applications (< 10 ppmv). Such an arrangement may not require that the zinc sulfide be regenerated since the sulfur concentration of the cleaned gas is low enough that the zinc oxide may be discarded when exhausted.

  16. Economic Evaluation for the Production of Sorbents and Catalysts Derived from Hydrous Titanium Oxide Microspheres Prepared by the HMTA Internal Gelation Process

    SciTech Connect

    Collins, J.L.

    2001-01-11

    Hydrous metal oxides of Zr, Ti, Hf, Fe, Al, etc. are inorganic ion exchangers that have high selectivities and efficiencies for separating and removing fission products, actinides, and other undesirable elements from aqueous waste streams. In most cases, these ion exchangers are commercially available only as fine powders or as unstable granular particles that are not readily adaptable to continuous processing techniques such as column chromatography. Hydrous metal oxides can be prepared as microspheres by the internal gelation process. This process is unique in that it provides a means of making a usable engineered form of inorganic ion exchanger that can be used in large-scale column separations. With such material, the flow dynamics in column operations would be greatly enhanced. In addition, the microspheres are in a stable form that has little or no tendency to degrade under dynamic conditions. Another advantage of the process is that the gelation time and size of the microspheres can be controlled. Also, microspheres can be reproducibly prepared on either a small or a large scale-which is not always true for batch preparation of the powdered or granular forms. The use of these materials can be expanded in a number of ways. The process allows for the microspheres to be homogeneously embedded with fine particles of other selective ion exchangers, and for the microspheres (undried) to be chemically converted to microspheres of other ion-exchanger materials such as phosphates, silicophosphates, hexacyanoferrates, tungstates, and molybdates. This report presents an economic evaluation of the preparation of hydrous titanium oxide (HTiO) microspheres by an internal gelation process for use in making ion exchangers, catalysts, and getters. It also examines the estimated costs for a company to produce the material but does not discuss the price to be charged since that value would take into account company policy-matters that cannot be covered here. Since the volume

  17. Liquid-impregnated clay solid sorbents for CO2 removal from postcombustion gas streams

    SciTech Connect

    Siriwardane, R.; Robinson, C.

    2009-01-01

    A novel liquid-impregnated clay sorbent R. V. Siriwardane, U.S. Patent No. 6,908,497 B1 2003 was developed for carbon dioxide CO2 removal in the temperature range of ambient to 60°C for both fixed-bed and fluidized-bed reactor applications. The sorbent is regenerable at 80–100°C. A 20-cycle test conducted in an atmospheric reactor with simulated flue gas with moisture demonstrated that the sorbent retains its CO2 sorption capacity with CO2 removal efficiency of about 99% during the cyclic tests. The sorbents suitable for fluidized-bed reactor operations showed required delta CO2 capacity requirements for sorption of CO2 at 40°C and regeneration at 100°C. The parameters such as rate of sorption, heat of sorption, minimum fluidization velocities, and attrition resistance data that are necessary for the design of a reactor suitable for capture and regeneration were also determined for the sorbent. A 20-cycle test conducted in the presence of flue-gas pollutant sulfur dioxide—SO2 20 parts per million —indicated that the sorbent performance was not affected by the presence of SO2.

  18. FURNACE INJECTION OF ALKALINE SORBENTS FOR SULFURIC ACID CONTROL

    SciTech Connect

    Gary M. Blythe

    2003-10-01

    -annual Technical Progress Report for the time period April 1, 2001 through September 30, 2001. Additional balance of plant impact information for the two tests was reported in the Technical Progress Report for the time period October 1, 2001 through March 30, 2002. Additional information became available about the effects of byproduct magnesium hydroxide injection on SCR catalyst coupons during the long-term test at BMP, and those results were reported in the report for the time period April 1, 2002 through September 30, 2002. During the current period, process economic estimates were developed, comparing the costs of the furnace magnesium hydroxide slurry injection process tested as part of this project to a number of other candidate SO{sub 3}/sulfuric acid control technologies for coal-fired power plants. The results of this economic evaluation are included in this progress report.

  19. Sorbents for CO2 capture from high carbon fly ashes.

    PubMed

    Maroto-Valer, M Mercedes; Lu, Zhe; Zhang, Yinzhi; Tang, Zhong

    2008-11-01

    Fly ashes with high-unburned-carbon content, referred to as fly ash carbons, are an increasing problem for the utility industry, since they cannot be marketed as a cement extender and, therefore, have to be disposed. Previous work has explored the potential development of amine-enriched fly ash carbons for CO2 capture. However, their performance was lower than that of commercially available sorbents, probably because the samples investigated were not activated prior to impregnation and, therefore, had a very low surface area. Accordingly, the work described here focuses on the development of activated fly ash derived sorbents for CO2 capture. The samples were steam activated at 850 degrees C, resulting in a significant increase of the surface area (1075 m2/g). The activated samples were impregnated with different amine compounds, and the resultant samples were tested for CO2 capture at different temperatures. The CO2 adsorption of the parent and activated samples is typical of a physical adsorption process. The impregnation process results in a decrease of the surface areas, indicating a blocking of the porosity. The highest adsorption capacity at 30 and 70 degrees C for the amine impregnated activated carbons was probably due to a combination of physical adsorption inherent from the parent sample and chemical adsorption of the loaded amine groups. The CO2 adsorption capacities for the activated amine impregnated samples are higher than those previously published for fly ash carbons without activation (68.6 vs. 45 mg CO2/g sorbent).

  20. The Evolutionary Development of CAI Evaluation Approaches.

    ERIC Educational Resources Information Center

    Avner, R. A.

    The role of evaluation in the development of evolutionary procedures is briefly described and highlighted. Four aspects of evaluation technique which distinguish efficient from inefficient CAI programs are identified. Evaluation of products is also characterized. Findings of a continuing survey of students via questionnaire as to the value of…

  1. Solid sorbent control of nitrogen oxides (NOx). Final report, September 1996--January 1999

    SciTech Connect

    Lee, M.R.

    1999-01-18

    Solid materials have demonstrated applicable control of combustion-source NOx. A support material of (gamma)-alumina can provide improved NOx sorption in comparison to a previously applied sorbent, magnesia-coated vermiculite. NOx sorption of treated (gamma)-alumina correlates with the ionization potential of the group-1 element. General mechanisms of NOx sorption have been developed for untreated, K{sub 2}CO{sub 3}-treated and KOH-treated (gamma)-alumina. Sorption of NO appears to increase formation of nitrite. Untreated (gamma)-alumina formed little nitrite. For the treated (gamma)-alumina, the ratio of nitrite-nitrate formed relates to the ratio of NO-to-NO{sub 2} sorbed. Additional NO{sub 2} exposure converts nitrite into nitrate and NO. This nitrite-to-nitrate conversion correlates with the thermal stability of subsurface species. In addition, thermal-decomposition tests indicated similarities of NOx-exposed sorbents to nitrite and nitrate salts. The proposed mechanisms suggest that formed nitrite stability is crucial to improving NOx sorption. Effects of additional gases (O{sub 2}, SO{sub 2}, CO{sub 2}, or water vapor) to NO and NO{sub 2} sorption at 25 and 250 deg C by untreated, K{sub 2}CO{sub 3}-treated and KOH-treated (gamma)-alumina were evaluated. Only SO{sub 2} and water vapor were observed to affect NOx sorption.

  2. Mercury Vapor Release from Broken Compact Fluorescent Lamps and In Situ Capture by New Nanomaterial Sorbents

    PubMed Central

    2008-01-01

    The projected increase in the use of compact fluorescent lamps (CFLs) motivates the development of methods to manage consumer exposure to mercury and its environmental release at the end of lamp life. This work characterizes the time-resolved release of mercury vapor from broken CFLs and from underlying substrates after removal of glass fragments to simulate cleanup. In new lamps, mercury vapor is released gradually in amounts that reach 1.3 mg or 30% of the total lamp inventory after four days. Similar time profiles but smaller amounts are released from spent lamps or from underlying substrates. Nanoscale formulations of S, Se, Cu, Ni, Zn, Ag, and WS2 are evaluated for capture of Hg vapor under these conditions and compared to conventional microscale formulations. Adsorption capacities range over 7 orders of magnitude, from 0.005 (Zn micropowder) to 188 000 μg/g (unstabilized nano-Se), depending on sorbent chemistry and particle size. Nanosynthesis offers clear advantages for most sorbent chemistries. Unstabilized nano-selenium in two forms (dry powder and impregnated cloth) was successfully used in a proof-of-principle test for the in situ, real-time suppression of Hg vapor escape following CFL fracture. PMID:18754507

  3. Mercury vapor release from broken compact fluorescent lamps and in situ capture by new nanomaterial sorbents.

    PubMed

    Johnson, Natalie C; Manchester, Shawn; Sarin, Love; Gao, Yuming; Kulaots, Indrek; Hurt, Robert H

    2008-08-01

    The projected increase in the use of compact fluorescent lamps (CFLs) motivates the development of methods to manage consumer exposure to mercury and its environmental release at the end of lamp life. This work characterizes the time-resolved release of mercury vapor from broken CFLs and from underlying substrates after removal of glass fragments to simulate cleanup. In new lamps, mercury vapor is released gradually in amounts that reach 1.3 mg or 30% of the total lamp inventory after four days. Similar time profiles but smaller amounts are released from spent lamps or from underlying substrates. Nanoscale formulations of S, Se, Cu, Ni, Zn, Ag, and WS2 are evaluated for capture of Hg vapor under these conditions and compared to conventional microscale formulations. Adsorption capacities range over 7 orders of magnitude, from 0.005 (Zn micropowder) to 188 000 microg/g (unstabilized nano-Se), depending on sorbent chemistry and particle size. Nanosynthesis offers clear advantages for most sorbent chemistries. Unstabilized nano-selenium in two forms (dry powder and impregnated cloth) was successfully used in a proof-of-principle test for the in situ, real-time suppression of Hg vapor escape following CFL fracture.

  4. Continuous fluidized-bed contactor with recycle of sorbent

    DOEpatents

    Scott, Charles D.; Petersen, James N.; Davison, Brian H.

    1996-01-01

    A continuous fluidized-bed contactor containing sorbent particles is used to remove solutes from liquid solvents. As the sorbent particles, for example gel beads, sorb the solute, for example metal ion species, the sorbent particles tend to decrease in diameter. These smaller loaded sorbent particles rise to the top of the contactor, as larger sorbent particles remain at the bottom of the contactor as a result of normal hydraulic forces. The smaller loaded sorbent particles are then recovered, regenerated, and reintroduced into the contactor. Alternatively, the loaded sorbent particles may also slightly increase in diameter, or exhibit no change in diameter but an increase in density. As a result of normal hydraulic forces the larger loaded sorbent particles fall to the bottom of the contactor. The larger loaded sorbent particles are then recovered, regenerated, and reintroduced into the contactor.

  5. Continuous fluidized-bed contactor with recycle of sorbent

    DOEpatents

    Scott, C.D.; Petersen, J.N.; Davison, B.H.

    1996-07-09

    A continuous fluidized-bed contactor containing sorbent particles is used to remove solutes from liquid solvents. As the sorbent particles, for example gel beads, sorb the solute, for example metal ion species, the sorbent particles tend to decrease in diameter. These smaller loaded sorbent particles rise to the top of the contactor, and larger sorbent particles remain at the bottom of the contactor as a result of normal hydraulic forces. The smaller loaded sorbent particles are then recovered, regenerated, and reintroduced into the contactor. Alternatively, the loaded sorbent particles may also slightly increase in diameter, or exhibit no change in diameter but an increase in density. As a result of normal hydraulic forces the larger loaded sorbent particles fall to the bottom of the contactor. The larger loaded sorbent particles are then recovered, regenerated, and reintroduced into the contactor. 8 figs.

  6. Development of a School Leadership Evaluation System

    ERIC Educational Resources Information Center

    Orlando, Nik

    2014-01-01

    This action research study examined the effectiveness of the process implemented by Partnerships to Uplift Communities (PUC) Schools Charter Management Organization to develop their school leader evaluation system in collaboration with current PUC school leaders. The development of the leadership evaluation system included the collective voices of…

  7. New Sorbents for Removing Arsenic From Water

    NASA Astrophysics Data System (ADS)

    McConchie, D. M.; Genc-Fuhrman, H.; Clark, M. W.; Caldicott, W.; Davies-McConchie, F. G.

    2004-12-01

    Elevated concentrations of arsenic in the drinking water used in many countries, including some of the poorest developing countries, and recognition that consuming this water can have serious consequences for human health, have led to increased investigations of ways to obtain safe water supplies. Finding new groundwater resources is a possible solution but this is a costly strategy that has no guarantee of success, particularly in areas where water is already a scarce commodity. The alternative is to treat water that is already available, but existing technologies are usually too expensive, too difficult to operate and maintain, or not completely effective when used in less developed countries or remote areas. There is therefore, an urgent need to find a simple and effective but inexpensive sorbent for arsenic that can be used to treat large volumes of water under less than ideal conditions. In this paper we present the results of field and laboratory trials that used a new, highly cost-effective, sorbent to remove arsenic from contaminated water. BauxsolT is the name given to the cocktail of minerals prepared by treating caustic bauxite refinery residues with Mg and Ca to produce a substance with a reaction pH of about 8.5, a high acid neutralizing capacity and an excellent ability to trap trace metals, metalloids and some other ionic species. The trapped ions are tightly bound by processes that include; precipitation of low solubility neoformational minerals, isomorphous substitution, solid-state diffusion, and adsorption; it is also an excellent flocculant. Although ordinary BauxsolT has an excellent ability to bind arsenate, and to a lesser extent arsenite, this ability can be further increased for particular water types by using activated BauxsolT or BauxsolT combined with small amounts of other reagents. Field trials conducted at the Gilt Edge Mine, South Dakota, showed that the addition of BauxsolT to highly sulfidic waste rock reduced the arsenic

  8. Electro membrane extraction using sorbent filled porous membrane bag.

    PubMed

    Naing, Nyi Nyi; Li, Sam Fong Yau; Lee, Hian Kee

    2015-12-01

    Electro membrane extraction-solid-liquid phase microextraction (EME-SLPME) was developed for the first time to determine phenolic contaminants in water. The extraction system consisted of a solid/liquid interface that permitted a three-phase microextraction approach involving an aqueous sample (donor phase): an organic solvent-sorbent within a membrane bag, and an organic solvent (extractant phase), operated in a direct immersion sampling system. The sorbent, reduced graphene oxide/polyvinyl alcohol, synthesized using graphene oxide and polyvinyl alcohol by dispersing the graphene oxide in polyvinyl alcohol and chemically reducing it in aqueous solution. The prepared sorbent was dispersed in 1-octanol and the solution was immobilized by sonication in the membrane bag wall pores which was in contact with the aqueous donor solution and organic extractant solvent (1-octanol) in the main bag itself. The analytes were transported by application of an electrical potential difference of 100V across the sorbent/solvent phase from the aqueous sample into the organic extractant phase in the membrane bag. After extraction and derivatization, gas chromatography-mass spectrometry was used to determine the derivatized analytes. This proposed EME-LSPME procedure provided high extraction efficiency with relative recoveries up to 99.6%. A linearity range of between 0.05 and 100μgL(-1) with corresponding coefficients of determination (r(2)) of between 0.987 and 0.996 were obtained. The limits of detection were in the range of between 0.003 and 0.053μgL(-1). This proposed method was successfully applied to the extraction of phenolic contaminants from water sample. PMID:26530143

  9. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    SciTech Connect

    David A. Green; Brian S. Turk; Raghubir P. Gupta; William J. McMichael; Douglas P. Harrison; Ya Liang

    2002-04-01

    The objective of this project is to develop a simple, inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbents being investigated in this project are primarily alkali carbonates, and particularly sodium carbonate and potassium carbonate, which are converted to bicarbonates, through reaction with carbon dioxide and water vapor. Bicarbonates are regenerated to carbonates when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. This quarter, electrobalance tests conducted at LSU indicated that exposure of sorbent to water vapor prior to contact with carbonation gas does not significantly increase the reaction rate. Calcined fine mesh trona has a greater initial carbonation rate than calcined sodium bicarbonate, but appears to be more susceptible to loss of reactivity under severe calcination conditions. The Davison attrition indices for Grade 5 sodium bicarbonate, commercial grade sodium carbonate and extra fine granular potassium carbonate were, as tested, outside of the range suitable for entrained bed reactor testing. Fluidized bed testing at RTI indicated that in the initial stages of reaction potassium carbonate removed 35% of the carbon dioxide in simulated flue gas, and is reactive at higher temperatures than sodium carbonate. Removals declined to 6% when 54% of the capacity of the sorbent was exhausted. Carbonation data from electrobalance testing was correlated using a shrinking core reaction model. The activation energy of the reaction of sodium carbonate with carbon dioxide and water vapor was determined from nonisothermal thermogravimetry.

  10. Hot coal-gas desulfurization with manganese-based sorbents

    SciTech Connect

    Berns, J.; Hepworth, M.T.; Slimane, R.B.; Gasper-Galvin, L.D.; Fisher, E.P.; Venkataraman, V.K.

    1996-08-01

    Manganese based hot-gas-desulfurization sorbents are under investigation for use in Integrated Gasification Combined Cycle advanced electric-power-generation systems. The objective of this project is to develop a regenerable Mn-based pellet formulation that can achieve low sulfur partial pressures, has a high capacity for sulfur and sufficient strength for potential use in fluidized beds, and can be regenerated for many cycles. Fifteen different formulations of manganese sesquioxide, each with either titania or alumina, were prepared and characterized at the University of Minnesota. Each formulation was indurated under conditions sufficient to achieve 1 lb/pellet/mm of diameter crush strength. Sulfidation screening was performed in a thermogravimetric analyzer at 500 to 900 C. A sorbent containing MnCO{sub 3} and TiO{sub 2}, which showed superior crush strength and reactivity, was selected for multi-cycle fixed-bed testing at the Morgantown Energy Technology Center. Four cycles of sulfidation showed that the sorbent had excellent efficiency and capacity for sulfur removal. Good regenerability was achieved with air-steam at 871 C.

  11. Aflatoxin B1 binding to sorbents in bovine ruminal fluid.

    PubMed

    Spotti, M; Fracchiolla, M L; Arioli, F; Caloni, F; Pompa, G

    2005-08-01

    A recent approach to the problem of contamination of agricultural products by aflatoxin B(1) (AFB(1)) is to add non-nutritional adsorbents to animal diets in order to sequester ingested aflatoxins. We conducted in vitro experiments to develop a rapid and cheap model using ruminal fluid to assess the ability of sorbent materials to bind AFB(1). Seven sorbents (hydrated sodium calcium aluminosilicate; clinoptilolite; zeolite; two types of bentonite; sepiolite; and PHIL 75), commonly added to bovine diets were incubated in water and ruminal fluid in the presence of AFB(1). Hydrated sodium calcium aluminosilicate, sepiolite and one of the bentonites bound 100% of the AFB(1) in the presence of both ruminal fluid and water; clinoptilolite bound about 80% of AFB(1) in both liquids; whereas the affinities for the mycotoxin of zeolite (50%) and the other sample of bentonite (60%) in water seem to be increased by about 40% in ruminal fluid incubations. PHIL 75 had the poorest binding ability: about 30% in water and 45% in ruminal fluid. In view of the differences in toxin binding in water and ruminal fluid, it is preferable to use the ruminal fluid model for the in vitro pre-screening of sorbent materials potentially useful as adjuvants to ruminant feeds. PMID:16215841

  12. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    SciTech Connect

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Alejandro Lopez-Ortiz; Douglas P. Harrison; Ya Liang

    2001-07-01

    Sodium based sorbents including sodium carbonate may be used to capture carbon dioxide from flue gas. A relatively concentrated carbon dioxide stream may be recoverable for sequestration when the sorbent is regenerated. Electrobalance tests indicated that sodium carbonate monohydrate was formed in a mixture of helium and water vapor at temperatures below 65 C. Additional compounds may also form, but this could not be confirmed. In the presence of carbon dioxide and water vapor, both the initial reaction rate of sodium carbonate with carbon dioxide and water and the sorbent capacity decreased with increasing temperature, consistent with the results from the previous quarter. Increasing the carbon dioxide concentration at constant temperature and water vapor concentration produced a measurable increase in rate, as did increasing the water vapor concentration at constant carbon dioxide concentration and temperature. Runs conducted with a flatter TGA pan resulted in a higher initial reaction rate, presumably due to improved gas-solid contact, but after a short time, there was no significant difference in the rates measured with the different pans. Analyses of kinetic data suggest that the surface of the sodium carbonate particles may be much hotter than the bulk gas due to the highly exothermic reaction with carbon dioxide and water, and that the rate of heat removal from the particle may control the reaction rate. A material and energy balance was developed for a cyclic carbonation/calcination process which captures about 26 percent of the carbon dioxide present in flue gas available at 250 C.

  13. Advanced in-duct sorbent injection for SO{sub 2} control. Topical report number 3, Subtask 2.3: Sorbent optimization

    SciTech Connect

    Rosenhoover, W.A.; Maskew, J.T.; Withum, J.A.; Stouffer, M.R.

    1994-11-01

    The objective of this research project is to develop second-generation duct injection technology as a cost-effective compliance option for the 1990 Clean Air Act Amendments. Specific process performance goals are to achieve 90% SO{sub 2} removal and 60% sorbent utilization efficiency. Research is focused on the Advanced Coolside process, which has shown the potential of achieving these targets. The objective of Subtask 2.3, Sorbent Optimization, was to explore means of improving performance and economics of the Advanced Coolside process through optimizing the sorbent system. Pilot plant tests of commercial and specially prepared hydrated limes showed that the process is relatively insensitive to sorbent source. This can be an important economic advantage, allowing the use of the lowest cost sorbent available at a site. A pilot plant hydration study conducted in cooperation with Dravo Lime Company further indicated the relative insensitivity of process performance to lime source and to lime physical properties. Pilot plant tests indicated that the use of very small amounts of additives in the Advanced Coolside process can improve performance under some circumstances; however, additives are not necessary to exceed process performance targets.

  14. Method of removing hydrogen sulfide from gases utilizing a zinc oxide sorbent and regenerating the sorbent

    DOEpatents

    Jalan, Vinod M.; Frost, David G.

    1984-01-01

    A spent solid sorbent resulting from the removal of hydrogen sulfide from a fuel gas flow is regenerated with a steam-air mixture. The mixture of steam and air may also include additional nitrogen or carbon dioxide. The gas mixture contacts the spent sorbent containing metal sulfide at a temperature above 500.degree. C. to regenerate the sulfide to metal oxide or carbonate. Various metal species including the period four transition metals and the lanthanides are suitable sorbents that may be regenerated by this method. In addition, the introduction of carbon dioxide gas permits carbonates such as those of strontium, barium and calcium to be regenerated. The steam permits regeneration of spent sorbent without formation of metal sulfate. Moreover, the regeneration will proceed with low oxygen concentrations and will occur without the increase in temperature to minimize the risk of sintering and densification of the sorbent.

  15. The antimicrobial efficiency of silver activated sorbents

    NASA Astrophysics Data System (ADS)

    Đolić, Maja B.; Rajaković-Ognjanović, Vladana N.; Štrbac, Svetlana B.; Rakočević, Zlatko Lj.; Veljović, Đorđe N.; Dimitrijević, Suzana I.; Rajaković, Ljubinka V.

    2015-12-01

    This study is focused on the surface modifications of the materials that are used for antimicrobial water treatment. Sorbents of different origin were activated by Ag+-ions. The selection of the most appropriate materials and the most effective activation agents was done according to the results of the sorption and desorption kinetic studies. Sorption capacities of selected sorbents: granulated activated carbon (GAC), zeolite (Z), and titanium dioxide (T), activated by Ag+-ions were following: 42.06, 13.51 and 17.53 mg/g, respectively. The antimicrobial activity of Ag/Z, Ag/GAC and Ag/T sorbents were tested against Gram-negative bacteria E. coli, Gram-positive bacteria S. aureus and yeast C. albicans. After 15 min of exposure period, the highest cell removal was obtained using Ag/Z against S. aureus and E. coli, 98.8 and 93.5%, respectively. Yeast cell inactivation was unsatisfactory for all three activated sorbents. The antimicrobial pathway of the activated sorbents has been examined by two separate tests - Ag+-ions desorbed from the activated surface to the aqueous phase and microbial cell removal caused by the Ag+-ions from the solid phase (activated surface sites). The results indicated that disinfection process significantly depended on the microbial-activated sites interactions on the modified surface. The chemical state of the activating agent had crucial impact to the inhibition rate. The characterization of the native and modified sorbents was performed by X-ray diffraction technique, X-ray photoelectron spectroscopy and scanning electron microscope. The concentration of adsorbed and released ions was determined by inductively coupled plasma optical emission spectroscopy and mass spectrometry. The antimicrobial efficiency of activated sorbents was related not only to the concentration of the activating agent, but moreover on the surface characteristics of the material, which affects the distribution and the accessibility of the activating agent.

  16. Magnetic sorbents added to soil slurries lower Cr aqueous concentration

    NASA Astrophysics Data System (ADS)

    Aravantinos, Konstantinos; Isari, Ekavi; Karapanagioti, Hrissi K.; Manariotis, Ioannis D.; Werner, David

    2016-04-01

    Activated carbon (AC) acts as a strong binding agent that lowers the pollutant concentration and, thus its toxicity. Another promising sorbent material in environmental applications is biochar (BC) which is obtained from the incomplete combustion of carbon-rich biomass under oxygen-limited conditions. Both of these materials could be used as soil or sediment amendments that would lower the toxicity in the aqueous phase. A draw back of this technique is that although the pollutant will remain non- bioavailable for many years being sorbed into these sorbents, it actually stays into the system. The objective of this study was (a) to synthesize a magnetic powdered activated carbon (AC/Fe) and magnetic powdered biochar (BC/Fe) produced from a commercial AC sample and BC, respectively and (b) to evaluate the potential use of AC/Fe and BC/Fe to lower Cr concentration that desorb from two soils in their soil slurries. The two soil samples originate from the vicinity of a local metal shop. The BC was produced from olive pomace. The surface area, the pore volume, and the average pore size of each sorbent were determined using gas (N2) adsorption-desorption cycles and the Brunauer, Emmett, and Teller (BET) equation. Isotherms with 30 adsorption and 20 desorption points were conducted at liquid nitrogen temperature (77K). Open surface area and micropore volume were determined using t-plot method and Harkins & Jura equation. For both AC/Fe, surface area measurements resulted in 66% those of corresponding AC. For BC/Fe, the surface area was 82% that of BC. Our previous studies have shown that both AC/Fe and BC/Fe are effective sorbents for mercury in aqueous solutions but with lower sorption capacity compared to the initial materials (50-75% lower). Batch experiments with all sorbent samples and each soil were conducted at room temperature (25oC) in order to compare the sorption properties of the materials. The soil slurries demonstrated low Cr concentrations (10.9 and 14.6

  17. Collection of fission and activation product elements from fresh and ocean waters: a comparison of traditional and novel sorbents

    SciTech Connect

    Johnson, Bryce E.; Santschi, Peter H.; Addleman, Raymond S.; Douglas, Matthew; Davidson, Joseph D.; Fryxell, Glen E.; Schwantes, Jon M.

    2010-04-01

    Monitoring natural waters for the inadvertent release of radioactive fission products produced as a result of nuclear power generation downstream from these facilities is essential for maintaining water quality. To this end, we evaluated sorbents for simultaneous in-situ large volume extraction of radionuclides with both soft (e.g., Ag) and hard metal (e.g., Co, Zr, Nb, Ba, and Cs) or anionic (e.g., Ru, Te, Sb) character. In this study, we evaluated a number of conventional and novel nanoporous sorbents in both fresh and salt waters. In most cases, the nanoporous sorbents demonstrated enhanced retention of analytes. Salinity had significant effects upon sorbent performance and was most significant for hard cations, specifically Cs and Ba. The presence of natural organic matter had little effect on the ability of chemisorbents to extract target elements.

  18. Priority setting for evaluation: developing a strategic evaluation portfolio.

    PubMed

    Spilsbury, M J; Norgbey, S; Battaglino, C

    2014-10-01

    Resources for evaluation are frequently scarce and best use should be made of them to deliver against the typical purposes of an evaluation function to (i) enhance accountability and (ii) promote operational improvement and learning. This paper presents a method for analyzing and prioritizing potential evaluations to improve the selection of a portfolio of activities that give the greatest pay-off. The method establishes the relative priority of 'evaluation opportunities' against criteria that relate to the usual primary purposes of an evaluation function. The method was developed in the context of a multilateral organization but is of general utility to the wider evaluation community and, with suitable adaptation can be applied to help ensure that scarce evaluation resources are used to their best advantage. A range of benefits are expected to accrue to an organization from adopting a more thorough, analytical priority setting process. These include: The paper describes a priority setting method, including the key criteria that are used to assess 'evaluation opportunities', and presents different analyses of an evaluation portfolio. Examples from a practical application of the approach to the preparation of an evaluation work plan in a multilateral environmental agency are given.

  19. Selective removal of copper (II) from natural waters by nanoporous sorbents functionalized with chelating diamines

    SciTech Connect

    Chouyyok, Wilaiwan; Shin, Yongsoon; Davidson, Joseph D.; Samuels, William D.; LaFemina, Nikki H.; Rutledge, Ryan D.; Fryxell, Glen E.; Sangvanich, Thanapon; Yantasee, Wassana

    2010-04-13

    The essential trace metal copper has been identified as a pollutant of concern by the Environmental Protection Agency (EPA) because of its widespread occurrence in the environment, often being found in concentrations capable of causing problems in organisms in that ecosystem. In this work, three different nanoporous sorbents containing chelating diamine functionalities were evaluated for Cu2+ adsorption in natural waters; these sorbents are ethylenediamine functionalized self-assembled monolayers on mesoporous supports (EDA-SAMMS®, SAMMS is a registered trademark of Steward Advanced Materials), ethylenediamine functionalized activated carbon (AC-CH2-EDA), and 1,10-Phenanthroline functionalized mesoporous carbon (Phen-FMC). The pH dependence of Cu2+ sorption and the Cu2+ sorption capacities of sorbents were determined. The Cu2+ adsorption rates and metal ion selectivity of these sorbents were compared to those of commercial sorbents (Chelex-100 ion exchange resin and Darco KB-B activated carbon). All three chelating diamine sorbents showed the excellent Cu2+ removal (~ 95-99%) from river water and sea water over the pH range of 6.0-8.0. Even under acidic conditions (e.g. pH of 3), AC-CH2-EDA and Phen-FMC were able to remove approximately ~49-58% of Cu2+ in sea water. EDA-SAMMS and AC-CH2-EDA demonstrated rapid Cu2+ sorption kinetics (reaching equilibrium within 5 min) and large adsorption capacities (26 and 17 mg Cu/g sorbent, respectively) in sea water. They also showed good selectivity for Cu2+ over other metal ions (e.g. Ca2+, Fe2+, Ni2+, and Zn2+) in sea water.

  20. Psychological Evaluation and Prescription Development Handbook.

    ERIC Educational Resources Information Center

    Vigo County School Corp., Terre Haute, IN.

    Developed to aid children with learning difficulties, from mental retardation or brain injury to maladjustment or physical or environmental handicaps, the joint school services program provides psychological evaluation and prescription development. The handbook reviews theories of child development and surveys behavior modification and…

  1. Efficient Separations and Processing Crosscutting Program: Develop and test sorbents. Fiscal year 1996 annual progress report, October 1, 1995--September 30, 1996

    SciTech Connect

    Brown, G.N.

    1997-01-01

    Ion exchange removal of Cs, Sr, Tc, TRU, etc. has been proposed for minimizing the amount of HLW at Hanford. Purpose of this project is to test sequestering agents and substrates in representative physical/chemical/radiation environments. A small pilot-scale skid system was built. 7 ion exchange materials (CS-100, R-F, SuperLig 644, IE-911, TIE-96, NaTi) were evaluated for pretreatment of actual/simulated Hanford DSSF tank waste. An onsite technology demonstration was done at Hanford 100-N Area N-Springs. A second PADU test demonstrated the 3M web technology for radioactive Cs and Sr decontamination of 105-N-Reactor basin. Other collaborative efforts between PNNL and industry/university participants are reported.

  2. Soil washing enhancement with solid sorbents

    SciTech Connect

    El-Shoubary, Y.M.; Woodmansee, D.E.

    1996-12-31

    Soil washing is a dynamic, physical process that remediates contaminated soil through two mechanisms: particle size separation and transfer of the contaminant into the (mostly) liquid stream. The performance of different sorbents and additives to remove motor oil from sea sand was tested. Hydrocyclone, attrition scrubber, and froth flotation equipment were used for the decontamination study. Sorbents and additives were mixed with soils in the attrition scrubber prior to flotation. Sorbents used were granular activated carbon, powder activated carbon, and rubber tires. Chemical additives used were calcium hydroxide, sodium carbonate, Alconox{reg_sign}, Triton{reg_sign} X-100 and Triton{reg_sign} X-114. When a froth flotation run was performed using no additive, washed soils {open_quotes}tails{close_quotes} contained 4000 ppm of total oil and grease (TOG). However, when carbon or rubber (6% by weight) was added to the contaminated soils the washed soils {open_quotes}tails{close_quotes} contained 4000 ppm of total oil and grease (TOG). The addition of sodium carbonate or calcium hydroxide (6% by weight) had same effects as sorbents. In both cases washed soil {open_quotes}tails{close_quotes} contained total oil and grease of less than 1000 ppm. The use of these non-hazardous additives or sorbent can enhance the soil washing process and consequently saves on time (residence time in equipment design) required to achieve the target clean up levels. 18 refs., 12 figs.

  3. Synthesis and properties of nanostructured sol-gel sorbents for simultaneous removal of sulfur dioxide and nitrogen oxides from flue gas

    NASA Astrophysics Data System (ADS)

    Buelna Quijada, Genoveva

    2001-07-01

    Regenerative, alumina-supported, copper-based sorbent/catalysts provide a promising technique for simultaneous removal of SO2 and NO x from flue gas. These sorbents can remove over 90% of SO2 and 70+% of NOx while generating no wastes, reducing energy consumption, and producing valuable by-products. The lack of a cost-effective sorbent with low attrition rate and good reactivity has been the main hurdle to commercialization of this copper oxide process. Developing such a sorbent is the focus of this dissertation. This work examines using sol-gel techniques rather than traditional processes to produce gamma-alumina and copper coated 7-alumina granular sorbents. Important modifications to the established sol-gel synthesis process were made, which minimized generated wastes and reduced preparation time and sorbent cost. A laboratory scale semi-continuous process providing a basis for large-scale synthesis was developed. The effect of the copper content on the surface area and dispersion of the active species on sol-gel-derived sorbents coated by the one step and wet-impregnation methods was studied. The sol-gel-derived sorbents showed superior sulfation and regeneration properties than the existing commercial sorbents used in the copper oxide process in terms of sulfation capacity, fast regeneration, recovery of sorption capacity, and SO2 concentration in the regenerated effluent. The optimum temperature for NO reduction by NH3 over sol-gel-derived CuO/gamma-Al2O3 was found to be 350°C for both fresh and sulfated catalysts. This was also the optimum operating temperature for simultaneous removal of SO2 and NOx from simulated flue gas. At 350°C, the adsorption capacity of the sol-gel sorbent/catalyst was higher than UOP's sorbent, and very close to the capacity of ALCOA's sorbent, while the catalytic activity for NO reduction of the sol-gel-derived CuO/gamma-Al 2O3 sorbent fell between the commercial sorbents. The new mesoporous sol-gel-derived materials showed

  4. The Handbook of Leadership Development Evaluation

    ERIC Educational Resources Information Center

    Hannum, Kelly M., Ed.; Martineau, Jennifer W., Ed.; Reinelt, Claire, Ed.

    2007-01-01

    With the increase in the number of organizational leadership development programs, there is a pressing need for evaluation to answer important questions, improve practice, and inform decisions. The Handbook is a comprehensive resource filled with examples, tools, and the most innovative models and approaches designed to evaluate leadership…

  5. Sorbent Structural Testing on Carbon Dioxide Removal Sorbents for Advanced Exploration Systems

    NASA Technical Reports Server (NTRS)

    Watson, David; Knox, James C.; West, Phillip; Bush, Richard

    2016-01-01

    Long term space missions require carbon dioxide removal systems that can function with minimal downtime required for maintenance, low power consumption and maximum efficiency for CO2 removal. A major component of such a system are the sorbents used for the CO2 and desiccant beds. Sorbents must not only have adequate CO2 and H2O removal properties, but they must have the mechanical strength to prevent structural breakdown due to pressure and temperature changes during operation and regeneration, as well as resistance to breakdown due to moisture in the system from cabin air. As part of the studies used to select future CO2 sorbent materials, mechanical tests are performed on various zeolite sorbents to determine mechanical performance while dry and at various humidified states. Tests include single pellet crush, bulk crush and attrition tests. We have established a protocol for testing sorbents under dry and humid conditions, and previously tested the sorbents used on the International Space Station carbon dioxide removal assembly. This paper reports on the testing of a series of commercial sorbents considered as candidates for use on future exploration missions.

  6. FURTHER DEVELOPMENT OF MODIFIED MONOSODIUM TITANATE, AN IMPROVED SORBENT FOR PRETREATMENT OF HIGH LEVEL NUCLEAR WASTE AT THE SAVANNAH RIVER SITE

    SciTech Connect

    Taylor-Pashow, K.; Hobbs, D.; Fondeur, F.; Fink, S.

    2011-01-12

    High-level nuclear waste produced from fuel reprocessing operations at the Savannah River Site (SRS) requires pretreatment to remove Cs-137, Sr-90, and alpha-emitting radionuclides (i.e., actinides) prior to disposal onsite as low level waste. Separation processes planned at SRS include caustic side solvent extraction, for Cs-137 removal, and sorption of Sr-90 and alpha-emitting radionuclides onto monosodium titanate (MST). The predominant alpha-emitting radionuclides in the highly alkaline waste solutions include plutonium isotopes Pu-238, Pu-239, and Pu-240. This paper describes recent results from the development of an improved titanate material that exhibits increased removal kinetics and effective capacity for Sr-90 and alpha-emitting radionuclides compared to the baseline MST material.

  7. Sulfur tolerant highly durable CO.sub.2 sorbents

    DOEpatents

    Smirniotis, Panagiotis G.; Lu, Hong

    2012-02-14

    A sorbent for the capture of carbon dioxide from a gas stream is provided, the sorbent containing calcium oxide (CaO) and at least one refractory dopant having a Tammann temperature greater than about 530.degree. C., wherein the refractory dopant enhances resistance to sintering, thereby conserving performance of the sorbent at temperatures of at least about 530.degree. C. Also provided are doped CaO sorbents for the capture of carbon dioxide in the presence of SO.sub.2.

  8. LIFAC Sorbent Injection Desulfurization Demonstration Project

    SciTech Connect

    Not Available

    1992-01-01

    Sorbent injection is a potentially important alternative to conventional wet lime and limestone scrubbing, and this project is another effort to test alternative sorbent injection approaches. In comparison to wet systems, LIFAC, with recirculation of the sorbent, removes less sulfur dioxide - 75--85% relative to 90% or greater for conventional scrubbers -- and requires more reagent material. However, if the demonstration is wet scrubbing systems: LIFAC is relatively easy to retrofit to an existing boiler and requires less area than conventional wet FGD systems. LIFAC is less expensive to install than conventional wet FGD processes. LIFAC's overall costs measured on a dollar-per-ton SO[sub 2] removed basis are less, an important advantage in a regulatory regime with trading of emission allocations. LIFAC produces a dry, readily disposable waste by-product versus a wet product. LIFAC is relatively simple to operate.

  9. Encapsulated liquid sorbents for carbon dioxide capture.

    PubMed

    Vericella, John J; Baker, Sarah E; Stolaroff, Joshuah K; Duoss, Eric B; Hardin, James O; Lewicki, James; Glogowski, Elizabeth; Floyd, William C; Valdez, Carlos A; Smith, William L; Satcher, Joe H; Bourcier, William L; Spadaccini, Christopher M; Lewis, Jennifer A; Aines, Roger D

    2015-02-05

    Drawbacks of current carbon dioxide capture methods include corrosivity, evaporative losses and fouling. Separating the capture solvent from infrastructure and effluent gases via microencapsulation provides possible solutions to these issues. Here we report carbon capture materials that may enable low-cost and energy-efficient capture of carbon dioxide from flue gas. Polymer microcapsules composed of liquid carbonate cores and highly permeable silicone shells are produced by microfluidic assembly. This motif couples the capacity and selectivity of liquid sorbents with high surface area to facilitate rapid and controlled carbon dioxide uptake and release over repeated cycles. While mass transport across the capsule shell is slightly lower relative to neat liquid sorbents, the surface area enhancement gained via encapsulation provides an order-of-magnitude increase in carbon dioxide absorption rates for a given sorbent mass. The microcapsules are stable under typical industrial operating conditions and may be used in supported packing and fluidized beds for large-scale carbon capture.

  10. Encapsulated liquid sorbents for carbon dioxide capture

    NASA Astrophysics Data System (ADS)

    Vericella, John J.; Baker, Sarah E.; Stolaroff, Joshuah K.; Duoss, Eric B.; Hardin, James O.; Lewicki, James; Glogowski, Elizabeth; Floyd, William C.; Valdez, Carlos A.; Smith, William L.; Satcher, Joe H.; Bourcier, William L.; Spadaccini, Christopher M.; Lewis, Jennifer A.; Aines, Roger D.

    2015-02-01

    Drawbacks of current carbon dioxide capture methods include corrosivity, evaporative losses and fouling. Separating the capture solvent from infrastructure and effluent gases via microencapsulation provides possible solutions to these issues. Here we report carbon capture materials that may enable low-cost and energy-efficient capture of carbon dioxide from flue gas. Polymer microcapsules composed of liquid carbonate cores and highly permeable silicone shells are produced by microfluidic assembly. This motif couples the capacity and selectivity of liquid sorbents with high surface area to facilitate rapid and controlled carbon dioxide uptake and release over repeated cycles. While mass transport across the capsule shell is slightly lower relative to neat liquid sorbents, the surface area enhancement gained via encapsulation provides an order-of-magnitude increase in carbon dioxide absorption rates for a given sorbent mass. The microcapsules are stable under typical industrial operating conditions and may be used in supported packing and fluidized beds for large-scale carbon capture.

  11. Thermodynamic Properties of CO{sub 2} Capture Reaction by Solid Sorbents: Theoretical Predictions and Experimental Validations

    SciTech Connect

    Duan, Yuhua; Luebke, David; Pennline, Henry; Li, Liyu; King, David; Zhang,; Keling,; Zhao,; Lifeng,; Xiao, Yunhan

    2012-01-01

    It is generally accepted that current technologies for capturing CO{sub 2} are still too energy intensive. Hence, there is a critical need for development of new materials that can capture CO{sub 2} reversibly with acceptable energy costs. Accordingly, solid sorbents have been proposed to be used for CO{sub 2} capture applications through a reversible chemical transformation. By combining thermodynamic database mining with first principles density functional theory and phonon lattice dynamics calculations, a theoretical screening methodology to identify the most promising CO{sub 2} sorbent candidates from the vast array of possible solid materials has been proposed and validated. The calculated thermodynamic properties of different classes of solid materials versus temperature and pressure changes were further used to evaluate the equilibrium properties for the CO{sub 2} adsorption/desorption cycles. According to the requirements imposed by the pre- and post- combustion technologies and based on our calculated thermodynamic properties for the CO{sub 2} capture reactions by the solids of interest, we were able to screen only those solid materials for which lower capture energy costs are expected at the desired pressure and temperature conditions. These CO{sub 2} sorbent candidates were further considered for experimental validations. In this presentation, we first introduce our screening methodology with validating by solid dataset of alkali and alkaline metal oxides, hydroxides and bicarbonates which thermodynamic properties are available. Then, by studying a series of lithium silicates, we found that by increasing the Li{sub 2}O/SiO{sub 2} ratio in the lithium silicates their corresponding turnover temperatures for CO{sub 2} capture reactions can be increased. Compared to anhydrous K{sub 2}CO{sub 3}, the dehydrated K{sub 2}CO{sub 3}1.5H{sub 2}O can only be applied for post-combustion CO{sub 2} capture technology at temperatures lower than its phase transition (to

  12. Attrition resistant, zinc titanate-containing, reduced sulfur sorbents

    DOEpatents

    Vierheilig, Albert A.; Gupta, Raghubir P.; Turk, Brian S.

    2004-11-02

    The disclosure is directed to sorbent compositions for removing reduced sulfur species (e.g., H.sub.2 S, COS and CS.sub.2) a feed stream. The sorbent is formed from a multi-phase composition including a zinc titanate phase and a zinc oxide-aluminate phase. The sorbent composition is substantially free of unreacted alumina.

  13. Sorbent for use in hot gas desulfurization

    DOEpatents

    Gasper-Galvin, Lee D.; Atimtay, Aysel T.

    1993-01-01

    A multiple metal oxide sorbent supported on a zeolite of substantially silicon oxide is used for the desulfurization of process gas streams, such as from a coal gasifier, at temperatures in the range of about 1200.degree. to about 1600.degree. F. The sorbent is provided by a mixture of copper oxide and manganese oxide and preferably such a mixture with molybdenum oxide. The manganese oxide and the molybdenum are believed to function as promoters for the reaction of hydrogen sulfide with copper oxide. Also, the manganese oxide inhibits the volatilization of the molybdenum oxide at the higher temperatures.

  14. Alkaline sorbent injection for mercury control

    DOEpatents

    Madden, Deborah A.; Holmes, Michael J.

    2003-01-01

    A mercury removal system for removing mercury from combustion flue gases is provided in which alkaline sorbents at generally extremely low stoichiometric molar ratios of alkaline earth or an alkali metal to sulfur of less than 1.0 are injected into a power plant system at one or more locations to remove at least between about 40% and 60% of the mercury content from combustion flue gases. Small amounts of alkaline sorbents are injected into the flue gas stream at a relatively low rate. A particulate filter is used to remove mercury-containing particles downstream of each injection point used in the power plant system.

  15. Alkaline sorbent injection for mercury control

    DOEpatents

    Madden, Deborah A.; Holmes, Michael J.

    2002-01-01

    A mercury removal system for removing mercury from combustion flue gases is provided in which alkaline sorbents at generally extremely low stoichiometric molar ratios of alkaline earth or an alkali metal to sulfur of less than 1.0 are injected into a power plant system at one or more locations to remove at least between about 40% and 60% of the mercury content from combustion flue gases. Small amounts of alkaline sorbents are injected into the flue gas stream at a relatively low rate. A particulate filter is used to remove mercury-containing particles downstream of each injection point used in the power plant system.

  16. Synthesis, Optimization, and Performance Demonstration of Electrospun Carbon Nanofiber-Carbon Nanotube Composite Sorbents for Point-of-Use Water Treatment.

    PubMed

    Peter, Katherine T; Vargo, John D; Rupasinghe, Thilini P; De Jesus, Aribet; Tivanski, Alexei V; Sander, Edward A; Myung, Nosang V; Cwiertny, David M

    2016-05-11

    We developed an electrospun carbon nanofiber-carbon nanotube (CNF-CNT) composite with optimal sorption capacity and material strength for point-of-use (POU) water treatment. Synthesis variables including integration of multiwalled carbon nanotubes (CNTs) and macroporosity (via sublimation of phthalic acid), relative humidity (20 and 40%), and stabilization temperature (250 and 280 °C) were used to control nanofiber diameter and surface area (from electron microscopy and BET isotherms, respectively), surface composition (from XPS), and strength (from AFM nanoindentation and tensile strength tests). Composites were then evaluated using kinetic, isotherm, and pH-edge sorption experiments with sulfamethoxazole (log Kow = 0.89) and atrazine (log Kow = 2.61), representative micropollutants chosen for their different polarities. Although CNFs alone were poor sorbents, integration of CNTs and macroporosity achieved uptake comparable to granular activated carbon. Through reactivity comparisons with CNT dispersions, we propose that increasing macroporosity exposes the embedded CNTs, thereby enabling their role as the primary sorbent in nanofiber composites. Because the highest capacity sorbents lacked sufficient strength, our optimal formulation (polyacrylonitrile 8 wt %, CNT 2 wt %, phthalic acid 2.4 wt %; 40% relative humidity; 280 °C stabilization) represents a compromise between strength and performance. This optimized sorbent was tested with a mixture of ten organic micropollutants at environmentally relevant concentrations in a gravity-fed, flow-through filtration system, where removal trends suggest that both hydrophobic and specific binding interactions contribute to micropollutant uptake. Collectively, this work highlights the promise of CNF-CNT filters (e.g., mechanical strength, ability to harness CNT sorption capacity), while also prioritizing areas for future research and development (e.g., improved removal of highly polar micropollutants, sensitivity to

  17. Synthesis, Optimization, and Performance Demonstration of Electrospun Carbon Nanofiber-Carbon Nanotube Composite Sorbents for Point-of-Use Water Treatment.

    PubMed

    Peter, Katherine T; Vargo, John D; Rupasinghe, Thilini P; De Jesus, Aribet; Tivanski, Alexei V; Sander, Edward A; Myung, Nosang V; Cwiertny, David M

    2016-05-11

    We developed an electrospun carbon nanofiber-carbon nanotube (CNF-CNT) composite with optimal sorption capacity and material strength for point-of-use (POU) water treatment. Synthesis variables including integration of multiwalled carbon nanotubes (CNTs) and macroporosity (via sublimation of phthalic acid), relative humidity (20 and 40%), and stabilization temperature (250 and 280 °C) were used to control nanofiber diameter and surface area (from electron microscopy and BET isotherms, respectively), surface composition (from XPS), and strength (from AFM nanoindentation and tensile strength tests). Composites were then evaluated using kinetic, isotherm, and pH-edge sorption experiments with sulfamethoxazole (log Kow = 0.89) and atrazine (log Kow = 2.61), representative micropollutants chosen for their different polarities. Although CNFs alone were poor sorbents, integration of CNTs and macroporosity achieved uptake comparable to granular activated carbon. Through reactivity comparisons with CNT dispersions, we propose that increasing macroporosity exposes the embedded CNTs, thereby enabling their role as the primary sorbent in nanofiber composites. Because the highest capacity sorbents lacked sufficient strength, our optimal formulation (polyacrylonitrile 8 wt %, CNT 2 wt %, phthalic acid 2.4 wt %; 40% relative humidity; 280 °C stabilization) represents a compromise between strength and performance. This optimized sorbent was tested with a mixture of ten organic micropollutants at environmentally relevant concentrations in a gravity-fed, flow-through filtration system, where removal trends suggest that both hydrophobic and specific binding interactions contribute to micropollutant uptake. Collectively, this work highlights the promise of CNF-CNT filters (e.g., mechanical strength, ability to harness CNT sorption capacity), while also prioritizing areas for future research and development (e.g., improved removal of highly polar micropollutants, sensitivity to

  18. Developing the Ability for Making Evaluative Judgements

    ERIC Educational Resources Information Center

    Cowan, John

    2010-01-01

    It is suggested that a more specific emphasis should be placed in undergraduate education on the explicit development of the ability to make evaluative judgements. This higher level cognitive ability is highlighted as the foundation for much sound and successful personal and professional development throughout education, and in lifelong…

  19. Enterprise Professional Development--Evaluating Learning

    ERIC Educational Resources Information Center

    Murphy, Gerald A.; Calway, Bruce A.

    2010-01-01

    Whilst professional development (PD) is an activity required by many regulatory authorities, the value that enterprises obtain from PD is often unknown, particularly when it involves development of knowledge. This paper discusses measurement techniques and processes and provides a review of established evaluation techniques, highlighting…

  20. Developing and evaluating patient education materials.

    PubMed

    Monsivais, Diane; Reynolds, Audree

    2003-01-01

    Nurses should be involved in all aspects of patient education, including the development of print and web resources, but most nurses have not been educated in how to develop these resources. This article discusses the rationale for nurse involvement, describes guidelines for evaluating existing material for credibility and readability, and provides recommendations for rewriting material at an easier-to-read level.

  1. ASSESSMENT OF LOW COST NOVEL SORBENTS FOR COAL-FIRED POWER PLANT MERCURY CONTROL

    SciTech Connect

    Trevor Ley

    2004-01-01

    This is a Technical Report under a program funded by the Department of Energy's National Energy Technology Laboratory (NETL) to obtain the necessary information to assess the viability of lower cost alternatives to commercially available activated carbon for mercury control in coal-fired utilities. Novel sorbent evaluations at We Energies' Pleasant Prairie Power Plant (P4) Unit 1 (no SCR in place) have been completed. Nineteen sorbents were evaluated for mercury control. A batch injection rate of 1 lb/Mmacf for 1 hour was conducted for screening purposes at a temperature of 300 F. Four sorbents were further evaluated at three injection rates and two temperatures. The multi-pollutant control test system (PoCT) was installed on P4's Unit 2 (with an SCR) and sorbent evaluations are continuing. Evaluations will continue through the end of January 2004. Tests and analysis on samples from Powerton and Valley to yield waste characterization results for the COHPAC long-term tests are continuing. A no-cost time extension for work to be completed by March 31, 2004 was granted by DOE/NETL.

  2. Diatomaceous earth and activated bauxite used as granular sorbents for the removal of sodium chloride vapor from hot flue gas

    SciTech Connect

    Lee, S.H.D.; Swift, W.M.; Johnson, I.

    1980-01-01

    Diatomaceous earth and activated bauxite were tested as granular sorbents for use as filter media in granular-bed filters for the removal of gaseous alkali metal compounds from the hot (800/sup 0/C) flue gas of PFBC. Tests were performed at atmospheric pressure, using NaCl vapor transported in relatively dry simulated flue gas of PFBC. Either a fixed-bed combustor or a high-temperature sorption test rig was used. The effects of sorbent bed temperature, superficial gas velocity, gas hourly space velocity, and NaCl-vapor concentration in flue gas on the sorption behavior of these two sorbents and their ultimate sorption capacities were determined. Both diatomaceous earth and activated bauxite were found to be very effective in removing NaCl vapor from flue gas. Preliminary cost evaluations showed that they are economically attractive as granular sorbents for cleaning alkali vapor from simulated flue gas.

  3. Collection of Lanthanides and Actinides from Natural Waters with Conventional and Nanoporous Sorbents

    SciTech Connect

    Johnson, Bryce E.; Santschi, Peter H.; Chuang, Chia-Ying; Otosaka, Shigeyoshi; Addleman, Raymond S.; Douglas, Matthew; Rutledge, Ryan D.; Chouyyok, Wilaiwan; Davidson, Joseph D.; Fryxell, Glen E.; Schwantes, Jon M.

    2012-10-16

    Effective collection of trace-level lanthanides and actinides is advantageous for recovery and recycling of valuable resources, environmental remediation, chemical separations and in-situ monitoring. Using isotopic tracers, we have evaluated a number of conventional and nanoporous sorbent materials for their ability to capture and remove selected lanthanides (Ce and Eu) and actinides (Th, Pa, U, and Np) from fresh and salt water systems. In general, the nanostructured materials demonstrated a higher level of performance and consistency. Nanoporous silica surface modified with 3,4- hydroxypyridinone provided excellent collection and consistency in both river water and seawater. The MnO2 materials, particular the high surface area small particle material also demonstrated good performance. Other conventional sorbents typically performed at the levels below the nanostructured sorbents and demonstrate a larger variability and matrix dependency.

  4. Removal of dissolved textile dyes from wastewater by a compost sorbent

    USGS Publications Warehouse

    Tsui, L.S.; Roy, W.R.; Cole, M.A.

    2003-01-01

    The objective of this study was to evaluate the potential for treating dye-contaminated waste streams by sorption using compost as a low-cost sorbent. A mature, thermophilic compost sample was used to sorb CI Acid Black 24, CI Acid Orange 74, CI Basic Blue 9, CI Basic Green 4, CI Direct Blue 71, CI Direct Orange 39, CI Reactive Orange 16 and CI Reactive Red 2 from solution using a batch-sorption method. With the exception of the two reactive dyes, the sorption kinetics were favourable for a continuous-flow treatment process with the compost-dye mixtures reaching a steady state within 3-5 h. Based on limited comparisons, the affinity of the compost for each dye appeared to be competitive with other non-activated carbon sorbents. The results suggest that additional research on using compost as a sorbent for dye-contaminated solutions is warranted.

  5. ASSESSMENT OF LOW COST NOVEL SORBENTS FOR COAL-FIRED POWER PLANT MERCURY CONTROL

    SciTech Connect

    Sharon Sjostrom

    2002-02-22

    This is a Technical Report under a program funded by the Department of Energy's National Energy Technology Laboratory (NETL) to obtain the necessary information to assess the viability of lower cost alternatives to commercially available activated carbon for mercury control in coal-fired utilities. During this reporting period, several sorbent samples have been tested by URS in their laboratory fixed-bed system. The sorbents were evaluated under conditions simulating flue gas from power plants burning Powder River Basin (PRB) and low sulfur eastern bituminous coals. The equilibrium adsorption capacities of the sorbents for both elemental and oxidized mercury are presented. A team meeting discussing the overall program and meetings with Midwest Generation and Wisconsin Electric Power Company (WEPCO) concerning field testing occurred during this reporting period.

  6. Mechanistic and kinetic studies of high-temperature coal gas desulfurization sorbents

    SciTech Connect

    Lew, S.; Flytzani-Stephanopoulos, M.; Sarofim, A.F.

    1991-10-01

    The overall objective of this project was to investigate the properties of and evaluate mixed oxides of zinc and titanium for hot fuel gas desulfurization. Uncombined ZnO was also investigated as a base case. Detailed investigation of the reduction and sulfidation reactions of Zn-Ti-O sorbents was performed. The intrinsic kinetics and the product layer diffusion rates in reduction and sulfidation were determined. Kinetic experiments with sorbents containing various Zn/Ti atomic ratios were performed. Chemical phase and structural transformations were followed by various methods. The results were compared to similar experiments performed with ZnO. The purpose of these experiments was to determine how the presence of titanium dioxide affects the reduction and sulfidation of ZnO. This information would be used to identify and select the sorbent composition that gives the best combination of low reduction rate and acceptable sulfidation performance at temperatures exceeding 600{degree}C. (VC)

  7. A polyvinyl alcohol-functionalized sorbent for extraction and determination of aminoglycoside antibiotics in honey.

    PubMed

    Wang, Yuan; Ji, Shunli; Zhang, Feng; Zhang, Feifang; Yang, Bingcheng; Liang, Xinmiao

    2015-07-17

    A novel highly hydrophilic sorbent simply prepared by coating polyvinyl alcohol (PVA) onto silica gel was used for extraction and determination of aminoglycoside antibiotics (AAs). The fabricated PVA coating is aimed to effectively protect core silica gel inside and offers good hydrophilic property. In combination of hydrophilic interaction chromatography tandem mass spectrometry, the performance of the sorbent was evaluated by selecting four model AAs (dihydrostreptomycin, streptomycin, kanamycin, spectinomycin). The sorbent was found to have effective adsorption ability to hydrophilic AAs, which was superior or comparable to those of commercial ones. Good recoveries (84-112%) of model AAs spiked in honey were obtained with good precision (<12.4%) and the limit of quantitation for the proposed method was in the range of 7.8-19.4ng/mL.

  8. Collection of lanthanides and actinides from natural waters with conventional and nanoporous sorbents.

    PubMed

    Johnson, Bryce E; Santschi, Peter H; Chuang, Chia-Ying; Otosaka, Shigeyoshi; Addleman, Raymond Shane; Douglas, Matt; Rutledge, Ryan D; Chouyyok, Wilaiwan; Davidson, Joseph D; Fryxell, Glen E; Schwantes, Jon M

    2012-10-16

    Effective collection of trace-level lanthanides and actinides is advantageous for recovery and recycling of valuable resources, environmental remediation, chemical separations, and in situ monitoring. Using isotopic tracers, we have evaluated a number of conventional and nanoporous sorbent materials for their ability to capture and remove selected lanthanides (Ce and Eu) and actinides (Th, Pa, U, and Np) from fresh and salt water systems. In general, the nanostructured materials demonstrated a higher level of performance and consistency. Nanoporous silica surface modified with 3,4-hydroxypyridinone provided excellent collection and consistency in both river water and seawater. The MnO(2) materials, in particular the high surface area small particle material, also demonstrated good performance. Other conventional sorbents typically performed at levels below the nanostructured sorbents and demonstrate a larger variability and matrix dependency.

  9. A polyvinyl alcohol-functionalized sorbent for extraction and determination of aminoglycoside antibiotics in honey.

    PubMed

    Wang, Yuan; Ji, Shunli; Zhang, Feng; Zhang, Feifang; Yang, Bingcheng; Liang, Xinmiao

    2015-07-17

    A novel highly hydrophilic sorbent simply prepared by coating polyvinyl alcohol (PVA) onto silica gel was used for extraction and determination of aminoglycoside antibiotics (AAs). The fabricated PVA coating is aimed to effectively protect core silica gel inside and offers good hydrophilic property. In combination of hydrophilic interaction chromatography tandem mass spectrometry, the performance of the sorbent was evaluated by selecting four model AAs (dihydrostreptomycin, streptomycin, kanamycin, spectinomycin). The sorbent was found to have effective adsorption ability to hydrophilic AAs, which was superior or comparable to those of commercial ones. Good recoveries (84-112%) of model AAs spiked in honey were obtained with good precision (<12.4%) and the limit of quantitation for the proposed method was in the range of 7.8-19.4ng/mL. PMID:26047525

  10. Development and evaluation of needle trap device geometry and packing methods for automated and manual analysis.

    PubMed

    Warren, Jamie M; Pawliszyn, Janusz

    2011-12-16

    For air/headspace analysis, needle trap devices (NTDs) are applicable for sampling a wide range of volatiles such as benzene, alkanes, and semi-volatile particulate bound compounds such as pyrene. This paper describes a new NTD that is simpler to produce and improves performance relative to previous NTD designs. A NTD utilizing a side-hole needle used a modified tip, which removed the need to use epoxy glue to hold sorbent particles inside the NTD. This design also improved the seal between the NTD and narrow neck liner of the GC injector; therefore, improving the desorption efficiency. A new packing method has been developed and evaluated using solvent to pack the device, and is compared to NTDs prepared using the previous vacuum aspiration method. The slurry packing method reduced preparation time and improved reproducibility between NTDs. To evaluate the NTDs, automated headspace extraction was completed using benzene, toluene, ethylbenzene, p-xylene (BTEX), anthracene, and pyrene (PAH). NTD geometries evaluated include: blunt tip with side-hole needle, tapered tip with side-hole needle, slider tip with side-hole, dome tapered tip with side-hole and blunt with no side-hole needle (expanded desorptive flow). Results demonstrate that the tapered and slider tip NTDs performed with improved desorption efficiency.

  11. Strategic Design and Optimization of Inorganic Sorbents for Cesium, Strontium and Actinides

    SciTech Connect

    Edward J. Maginn

    2009-11-09

    The primary objective of the Notre Dame component of the project was computational in nature. The goal was to provide a design tool for the synthesis of optimized sorbents for the removal of cesium, strontium and actinides from nuclear waste solutions. Molecular modeling enables us to observe and better understand the molecular level interactions that govern the selectivity of specific radionuclides in a particular sorbent. The research focused on the development and validation of a suitable and transferable model for all the cations and ion exchangers of interest, nd then subsequent simulations which determined the siting and mobility of water and cations. Speciic accomplishments include: (1) improving existing intermolecular force fields to accurately model the sorbents of interest; (2) utilizing energy-minimizations and molecular dynamics simulations for structural prediction of CST and niobium-substituted CST materials; (3) determining Na+/water positions in polyoxoniobate materials using molecular dynamics simulations; and (4) developing Hybrid Monte Carlo methods for improved structural prediction.

  12. Instructional Technology Professional Development Evaluation: Developing a High Quality Model

    ERIC Educational Resources Information Center

    Gaytan, Jorge A.; McEwen, Beryl C.

    2010-01-01

    Background: The literature contains very few studies that focused on evaluating the impact of professional development activities on student learning. And, many of these studies failed to determine whether the professional development activities met their primary goal--to improve the learning process. Purpose: The purpose of this study was to use…

  13. Engineered Structured Sorbents for the Adsorption of Carbon Dioxide and Water Vapor from Manned Spacecraft Atmospheres: Applications and Modeling 2007/2008

    NASA Technical Reports Server (NTRS)

    Knox, James C.; Howard, David F.; Perry, Jay L.

    2007-01-01

    In NASA s Vision for Space Exploration, humans will once again travel beyond the confines of earth s gravity, this time to remain there for extended periods. These forays will place unprecedented demands on launch systems. They must not only blast out of earth s gravity well as during the Apollo moon missions, but also launch the supplies needed to sustain a larger crew over much longer periods. Thus all spacecraft systems, including those for the separation of metabolic carbon dioxide and water from a crewed vehicle, must be minimized with respect to mass, power, and volume. Emphasis is also placed on system robustness both to minimize replacement parts and ensure crew safety when a quick return to earth is not possible. This paper describes efforts to improve on typical packed beds of sorbent pellets by making use of structured sorbents and alternate bed configurations to improve system efficiency and reliability. The development efforts described offer a complimentary approach combining testing of subscale systems and multiphysics computer simulations to characterize the regenerative heating substrates and evaluation of engineered structured sorbent geometries. Mass transfer, heat transfer, and fluid dynamics are included in the transient simulations.

  14. Determination of dry carbon-based sorbent injection for mercury control in utility ESP and baghouses

    SciTech Connect

    Broderick, T.; Haythornthwaite, S.; Bell, W.; Selegue, T.; Perry, M.

    1998-12-31

    Domestic coal-fired power plants emit approximately 40 to 80 metric tons of mercury to the atmosphere annually. The mercury concentration in utility flue gas is in the dilute range of 0.1 to 1 parts per billion. The EPA is assessing whether such low concentrations of mercury emissions from coal-fired utilities pose any significant health risk and whether mercury regulations would be necessary or appropriate. In anticipation of possible mercury control regulations, ADA Technologies (ADA) and TDA Research, Inc (TDA) were funded by the Department of Energy (DOE) to evaluate carbon-based sorbents for mercury control at utility coal-fired power plants. Past investigations of the use of dry carbon-based sorbent injection for mercury control on pilot-scale utility flue gas applications have shown that these sorbents are capable of removing gas-phase mercury. ADA Technologies field-tested the mercury removal capability of several carbon-based sorbents manufactured by TDA. The test facility was a DOE-owned test facility built and operated by ADA at the Public Service Company of Colorado`s Comanche Station in Pueblo, Colorado. The pilot-scale test fixture is a 600-acfm particulate control module that can be configured as an electrostatic precipitator, a pulse-jet baghouse, or a reverse-gas baghouse. It extracts a slipstream of flue gas from a coal-fired utility boiler. Sorbent is injected into the flue gas slipstream upstream of the particulate control module and is removed by the module. ADA evaluated the mercury capture efficiency of the sorbents over a range of flue gas temperatures and injection rates. In addition, the effect of flyash on mercury capture was also investigated. The test facility is configured to take flue gas from either upstream or downstream of Comanche Station`s full-scale reverse-gas baghouse, allowing tests to be conducted with normal-ash or low-ash flue gas.

  15. Pore structure and reactivity changes in hot coal gas desulfurization sorbents

    SciTech Connect

    Sotirchos, S.V.

    1989-01-01

    A research program is proposed for the investigation of the dependence of the sorptive capacity of metal/metal oxide desulfurization sorbents on their pore size distribution and their intraparticle diffusivity. Integrated reaction/adsorption systems, chromatographic and gravimetric, will be used for successive reactivity, adsorption, and well as diffusivity, measurements. Single particle models that have been developed by our research group for gas-solid reactions with solid product will be used as basis for experimental data analysis and development of a general mathematical model for fixed-bed desulfurization and sorbent regeneration.

  16. Development of charcoal sorbents for helium cryopumping

    SciTech Connect

    Sedgley, D.W.; Tobin, A.G.

    1984-01-01

    Testing of the cryogenically cooled charcoal using fusion-compatible binders for pumping helium has shown promising results. The program demonstrated comparable or improved performance with these binders compared to the charcoal (type and size) using an epoxy binder.

  17. FURNACE SORBENT REACTIVITY TESTING FOR CONTROL OF SO2 EMISSIONS FROM ILLINOIS COALS

    EPA Science Inventory

    Research was undertaken to evaluate the potential of furnai sorbent injection (FSI) for sulf dioxide (S02) emission controlcoal-fired boilers utilizing coals indigenous to Illinois. Tests were run using four coals from the Illinois Basin and six calcium hydroxide [Ca(OH)2], sorbe...

  18. Sorbent utilization prediction methodology: sulfur control in fluidized-bed combustors

    SciTech Connect

    Fee, D.C.; Wilson, W.I.; Shearer, J.A.; Smith, G.W.; Lenc, J.F.; Fan, L.S.; Myles, K.M.; Johnson, I.

    1980-09-01

    The United States Government has embarked on an ambitious program to develop and commercialize technologies to efficiently extract energy from coal in an environmentally acceptable manner. One of the more promising new technologies for steam and power generation is the fluidized-bed combustion of coal. In this process, coal is burned in a fluidized bed composed mainly of calcined limestone sorbent. The calcium oxide reacts chemically to capture the sulfur dioxide formed during the combustion and to maintain the stack gas sulfur emissions at acceptable levels. The spent sulfur sorbent, containing calcium sulfate, is a dry solid that can be disposed of along with coal ash or potentially used. Other major advantages of fluidized-bed combustion are the reduction in nitrogen oxide emissions because of the relatively low combustion temperatures, the capability of burning wide varieties of fuel, the high carbon combustion efficiencies, and the high heat-transfer coefficients. A key to the widespread commercialization of fluidized-bed technology is the ability to accurately predict the amount of sulfur that will be captured by a given sorbent. This handbook meets this need by providing a simple, yet reliable, user-oriented methodology (the ANL method) that allows performance of a sorbent to be predicted. The methodology is based on only three essential sorbent parameters, each of which can be readily obtained from standardized laboratory tests. These standard tests and the subsequent method of data reduction are described in detail.

  19. INVESTIGATION OF MIXED METAL SORBENT/CATALYSTS FOR THE SIMULTANEOUS REMOVAL OF SULFUR AND NITROGEN OXIDES

    SciTech Connect

    Ates Akyurtlu; Jale F. Akyurtle

    2001-08-01

    Simultaneous removal of SO{sub 2} and NO{sub x} using a regenerable solid sorbent will constitute an important improvement over the use of separate processes for the removal of these two pollutants from stack gases and possibly eliminate several shortcomings of the individual SO{sub 2} and NO{sub x} removal operations. The work done at PETC and the DOE-funded investigation of the investigators on the sulfation and regeneration of alumina-supported cerium oxide sorbents have shown that they can perform well at relatively high temperatures (823-900 K) as regenerable desulfurization sorbents. Survey of the recent literature shows that addition of copper oxide to ceria lowers the sulfation temperature of ceria down to 773 K, sulfated ceria-based sorbents can function as selective SCR catalysts even at elevated temperatures, SO{sub 2} can be directly reduced to sulfur by CO on CuO-ceria catalysts, and ceria-based catalysts may have a potential for selective catalytic reduction of NO{sub x} by methane. These observations indicate a possibility of developing a ceria-based sorbent/catalyst which can remove both SO{sub 2} and NO{sub x} from flue gases within a relatively wide temperature window, produce significant amounts of elemental sulfur during regeneration, and use methane for the selective catalytic reduction of NO{sub x}.

  20. Tail-end Hg capture on Au/carbon-monolith regenerable sorbents.

    PubMed

    Izquierdo, M Teresa; Ballestero, Diego; Juan, Roberto; García-Díez, Enrique; Rubio, Begoña; Ruiz, Carmen; Pino, M Rosa

    2011-10-15

    In this work, a regenerable sorbent for Hg retention based on carbon supported Au nanoparticles has been developed and tested. Honeycomb structures were chosen in order to avoid pressure drop and particle entrainment in a fixed bed. Carbon-based supports were selected in order to easily modify the surface chemistry to favour the Au dispersion. Results of Hg retention and regeneration were obtained in a bench scale experimental installation working at high space velocities (for sorbent, 53,000 h(-1); for active phase, 2.6 × 10(8) h(-1)), 120 °C for retention temperature and Hg inlet concentration of 23 ppbv. Gold nanoparticles were shown to be the active phase for mercury capture through an amalgamating mechanism. The mercury captured by the spent sorbent can be easily released to be disposed or reused. Mercury evolution from spent sorbents was followed by TPD experiments showing that the sorbent can be regenerated at temperatures as low as 220 °C.

  1. CO{sub 2} Capture from Flue Gas Using Solid Molecular Basket Sorbents

    SciTech Connect

    Fillerup, Eric; Zhang, Zhonghua; Peduzzi, Emanuela; Wang, Dongxiang; Guo, Jiahua; Ma, Xiaoliang; Wang, Xiaoxing; Song, Chunshan

    2012-08-31

    The objective of this project is to develop a new generation of solid, regenerable polymeric molecular basket sorbent (MBS) for more cost-efficient capture and separation of CO{sub 2} from flue gas of coal-fired power plants. The primary goal is to develop a cost-effective MBS sorbent with better thermal stability. To improve the cost-effectiveness of MBS, we have explored commercially available and inexpensive support to replace the more expensive mesoporous molecular sieves like MCM-41 and SBA- 15. In addition, we have developed some advanced sorbent materials with 3D pore structure such as hexagonal mesoporous silica (HMS) to improve the CO{sub 2} working capacity of MBS, which can also reduce the cost for the whole CO{sub 2} capture process. During the project duration, the concern regarding the desorption rate of MBS sorbents has been raised, because lower desorption rate increases the desorption time for complete regeneration of the sorbent which in turn leads to a lower working capacity if the regeneration time is limited. Thus, the improvement in the thermal stability of MBS became a vital task for later part of this project. The improvement in the thermal stability was performed via increasing the polymer density either using higher molecular weight PEI or PEI cross-linking with an organic compound. Moreover, we have used the computational approach to estimate the interaction of CO{sub 2} with different MBSs for the fundamental understanding of CO{sub 2} sorption, which may benefit the development, design and modification of the sorbents and the process.

  2. Sorbent-Bed Crop-Drying System

    NASA Technical Reports Server (NTRS)

    Roberts, Barry C.

    1992-01-01

    Proposed aeration system helps reduce spoilage of stored grain or other crop stored in bulk. Air circulates through bin, sorbent bed, and heat exchanger. Outside air cools circulating air in heat exchanger. Sensors measure temperature and humidity, and adjust dampers to obtain requisite temperature and humidity. Suitable for grain bins and shipping barges.

  3. Carbon dioxide capture process with regenerable sorbents

    DOEpatents

    Pennline, Henry W.; Hoffman, James S.

    2002-05-14

    A process to remove carbon dioxide from a gas stream using a cross-flow, or a moving-bed reactor. In the reactor the gas contacts an active material that is an alkali-metal compound, such as an alkali-metal carbonate, alkali-metal oxide, or alkali-metal hydroxide; or in the alternative, an alkaline-earth metal compound, such as an alkaline-earth metal carbonate, alkaline-earth metal oxide, or alkaline-earth metal hydroxide. The active material can be used by itself or supported on a substrate of carbon, alumina, silica, titania or aluminosilicate. When the active material is an alkali-metal compound, the carbon-dioxide reacts with the metal compound to generate bicarbonate. When the active material is an alkaline-earth metal, the carbon dioxide reacts with the metal compound to generate carbonate. Spent sorbent containing the bicarbonate or carbonate is moved to a second reactor where it is heated or treated with a reducing agent such as, natural gas, methane, carbon monoxide hydrogen, or a synthesis gas comprising of a combination of carbon monoxide and hydrogen. The heat or reducing agent releases carbon dioxide gas and regenerates the active material for use as the sorbent material in the first reactor. New sorbent may be added to the regenerated sorbent prior to subsequent passes in the carbon dioxide removal reactor.

  4. Silver oxide sorbent for carbon dioxide

    NASA Technical Reports Server (NTRS)

    Colombo, G. V.

    1974-01-01

    Material can be regenerated at least 20 times by heating at 250 C. Sorbent is compatible with environment of high humidity; up to 20% by weight of carbon dioxide can be absorbed. Material is prepared from silver carbonate, potassium hydroxide or carbonate, and sodium silicate.

  5. METAL CAPTURE BY SORBENTS IN COMBUSTION PROCESSES

    EPA Science Inventory

    The article gives results of an investigation of the use of sorbents to control trace metal emissions from combustion processes and an exploration of the underlying mechanisms. mphasis was on mechanisms in which the metal vapor was reactively scavenged by simple commercial sorben...

  6. [Drinking water decontamination with isolative sorbent disinfectants].

    PubMed

    Krasnov, M S

    2004-01-01

    Drinking water can be decontaminated with the use of isolative sorbent disinfectants. Consideration of the effectiveness of water disinfectants and the sorptive power of porous materials against bacteria and viruses attested to the favour of iodine and silver-containing disinfectants and their compositions on porous aggressive carriers to be employed in extreme conditions such as on board crewed space vehicles.

  7. Predicting sorption of organic acids to a wide range of carbonized sorbents

    NASA Astrophysics Data System (ADS)

    Sigmund, Gabriel; Kah, Melanie; Sun, Huichao; Hofmann, Thilo

    2016-04-01

    Many contaminants and infochemicals are organic acids that undergo dissociation under environmental conditions. The sorption of dissociated anions to biochar and other carbonized sorbents is typically lower than that of neutral species. It is driven by complex processes that are not yet fully understood. It is known that predictive approaches developed for neutral compounds are unlikely to be suitable for organic acids, due to the effects of dissociation on sorption. Previous studies on the sorption of organic acids to soils have demonstrated that log Dow, which describes the decrease in hydrophobicity of acids upon dissociation, is a useful alternative to log Kow. The aim of the present study was to adapt a log Dow based approach to describe the sorption of organic acids to carbonized sorbents. Batch experiments were performed with a series of 9 sorbents (i.e., carbonized wood shavings, pig manure, and sewage sludge, carbon nanotubes and activated carbon), and four acids commonly used for pesticidal and biocidal purposes (i.e., 2,4-D, MCPA, 2,4-DB, and triclosan). Sorbents were comprehensively characterized, including by N2 and CO2 physisorption, Fourier transform infrared spectroscopy, and elemental analysis. The wide range of sorbents considered allows (i) discussing the mechanisms driving the sorption of neutral and anionic species to biochar, and (ii) their dependency on sorbate and sorbent properties. Results showed that the sorption of the four acids was influenced by factors that are usually not considered for neutral compounds (i.e., pH, ionic strength). Dissociation affected the sorption of the four compounds, and sorption of the anions ranged over five orders of magnitude, thus substantially contributing to sorption in some cases. For prediction purposes, most of the variation in sorption to carbonized sorbents (89%) could be well described with a two-parameter regression equation including log Dow and sorbent specific surface area. The proposed model

  8. Simple and rapid determination of phthalates using microextraction by packed sorbent and gas chromatography with mass spectrometry quantification in cold drink and cosmetic samples.

    PubMed

    Kaur, Ramandeep; Heena; Kaur, Ripneel; Rani, Susheela; Malik, Ashok Kumar

    2016-03-01

    A simple and rapid method using microextraction by packed sorbent coupled with gas chromatography and mass spectrometry has been developed for the analysis of five phthalates, namely, diethyl phthalate, benzyl-n-butyl phthalate, dicyclohexyl phthalate, di-n-butyl phthalate, and di-n-propyl phthalate, in cold drink and cosmetic samples. The various parameters that influence the microextraction by packed sorbent performance such as extraction cycle (extract-discard), type and amount of solvent, washing solvent, and pH have been studied. The optimal conditions of microextraction using C18 as the packed sorbent were 15 extraction cycles with water as washing solvent and 3 × 10 μL of ethyl acetate as the eluting solvent. Chromatographic separation was also optimized for injection temperature, flow rate, ion source, interface temperature, column temperature gradient and mass spectrometry was evaluated using the scan and selected ion monitoring data acquisition mode. Satisfactory results were obtained in terms of linearity with R(2) >0.9992 within the established concentration range. The limit of detection was 0.003-0.015 ng/mL, and the limit of quantification was 0.009-0.049 ng/mL. The recoveries were in the range of 92.35-98.90% for cold drink, 88.23-169.20% for perfume, and 88.90-184.40% for cream. Analysis by microextraction by packed sorbent promises to be a rapid method for the determination of these phthalates in cold drink and cosmetic samples, reducing the amount of sample, solvent, time and cost. PMID:26683135

  9. Simple and rapid determination of phthalates using microextraction by packed sorbent and gas chromatography with mass spectrometry quantification in cold drink and cosmetic samples.

    PubMed

    Kaur, Ramandeep; Heena; Kaur, Ripneel; Rani, Susheela; Malik, Ashok Kumar

    2016-03-01

    A simple and rapid method using microextraction by packed sorbent coupled with gas chromatography and mass spectrometry has been developed for the analysis of five phthalates, namely, diethyl phthalate, benzyl-n-butyl phthalate, dicyclohexyl phthalate, di-n-butyl phthalate, and di-n-propyl phthalate, in cold drink and cosmetic samples. The various parameters that influence the microextraction by packed sorbent performance such as extraction cycle (extract-discard), type and amount of solvent, washing solvent, and pH have been studied. The optimal conditions of microextraction using C18 as the packed sorbent were 15 extraction cycles with water as washing solvent and 3 × 10 μL of ethyl acetate as the eluting solvent. Chromatographic separation was also optimized for injection temperature, flow rate, ion source, interface temperature, column temperature gradient and mass spectrometry was evaluated using the scan and selected ion monitoring data acquisition mode. Satisfactory results were obtained in terms of linearity with R(2) >0.9992 within the established concentration range. The limit of detection was 0.003-0.015 ng/mL, and the limit of quantification was 0.009-0.049 ng/mL. The recoveries were in the range of 92.35-98.90% for cold drink, 88.23-169.20% for perfume, and 88.90-184.40% for cream. Analysis by microextraction by packed sorbent promises to be a rapid method for the determination of these phthalates in cold drink and cosmetic samples, reducing the amount of sample, solvent, time and cost.

  10. Experiment and modeling of CO{sub 2} capture from flue gases at high temperature in a fluidized bed reactor with Ca-based sorbents

    SciTech Connect

    Fan Fang; Zhen-Shan Li; Ning-Sheng Cai

    2009-01-15

    The cyclic CO{sub 2} capture and CaCO{sub 3} regeneration characteristics in a small fluidized bed reactor were experimentally investigated with limestone and dolomite sorbents. Kinetic rate constants for carbonation and calcination were determined using thermogravimetric analysis (TGA) data. Mathematical models developed to model the Ca-based sorbent multiple cycles of CO{sub 2} capture and calcination in the bubbling fluidized bed reactor agreed with the experimental data. The experimental and simulated results showed that the CO{sub 2} in flue gases could be absorbed efficiently by limestone and dolomite. The time for high-efficiency CO{sub 2} capture decreased with an increasing number of cycles because of the loss of sorbent activity, and the final CO{sub 2} capture efficiency remained nearly constant as the sorbent reached its final residual capture capacity. In a continuous carbonation and calcination system, corresponding to the sorbent activity loss, the carbonation kinetic rates of sorbent undergoing various cycles are different, and the carbonation kinetic rates of sorbent circulating N times in the carbonation/calcination cycles are also different because of the different residence time of sorbent in the carbonator. Therefore, the average carbonation rate was given based on the mass balance and exit age distribution for sorbent in the carbonator. The CO{sub 2} capture characteristics in a continuous carbonation/calcination system were predicted, taking into consideration the mass balance, sorbent circulation rate, sorbent activity loss, and average carbonation kinetic rate, to give useful information for the reactor design and operation of multiple carbonation/calcination reaction cycles. 27 refs., 15 figs., 1 tab.

  11. Mercury Control with Calcium-Based Sorbents and Oxidizing Agents

    SciTech Connect

    Thomas K. Gale

    2005-07-01

    This Final Report contains the test descriptions, results, analysis, correlations, theoretical descriptions, and model derivations produced from many different investigations performed on a project funded by the U.S. Department of Energy, to investigate calcium-based sorbents and injection of oxidizing agents for the removal of mercury. Among the technologies were (a) calcium-based sorbents in general, (b) oxidant-additive sorbents developed originally at the EPA, and (c) optimized calcium/carbon synergism for mercury-removal enhancement. In addition, (d) sodium-tetrasulfide injection was found to effectively capture both forms of mercury across baghouses and ESPs, and has since been demonstrated at a slipstream treating PRB coal. It has been shown that sodium-tetrasulfide had little impact on the foam index of PRB flyash, which may indicate that sodium-tetrasulfide injection could be used at power plants without affecting flyash sales. Another technology, (e) coal blending, was shown to be an effective means of increasing mercury removal, by optimizing the concentration of calcium and carbon in the flyash. In addition to the investigation and validation of multiple mercury-control technologies (a through e above), important fundamental mechanism governing mercury kinetics in flue gas were elucidated. For example, it was shown, for the range of chlorine and unburned-carbon (UBC) concentrations in coal-fired utilities, that chlorine has much less effect on mercury oxidation and removal than UBC in the flyash. Unburned carbon enhances mercury oxidation in the flue gas by reacting with HCl to form chlorinated-carbon sites, which then react with elemental mercury to form mercuric chloride, which subsequently desorbs back into the flue gas. Calcium was found to enhance mercury removal by stabilizing the oxidized mercury formed on carbon surfaces. Finally, a model was developed to describe these mercury adsorption, desorption, oxidation, and removal mechanisms, including

  12. Testing and technology transfer for zinc titanate sorbent in a titania matrix. Technical report, September 1, 1995--November 30, 1995

    SciTech Connect

    Swisher, J.H.; Gupta, R.P.

    1995-12-31

    For new coal gasification systems, zinc-based sorbents are being developed to remove sulfur from the hot product gas prior to its use in combined-cycle gas turbines and high- temperature fuel cells. In general, the properties of these sorbents are considered to be very attractive, but there are still concerns about degradation of mechanical properties and sulfur capacity over many sulfidation- regeneration cycles. It is believed that containing zinc titanate in a matrix of excess titania could solve both problems, which is the objective of this project. During this quarter, plans were made for United Catalysts, Inc. to produce two batches of the sorbent using a commercial extrusion process. A subcontract was just issued to the Research Triangle Institute for sorbent characterization and for a 50- cycle performance test designed to simulate the General Electric Company`s moving-bed reactor conditions. In a parallel effort, numerous contacts were made on the technology transfer task.

  13. Multi-functional sorbents for the simultaneous removal of sulfur and lead compounds from hot flue gases.

    PubMed

    Zhao, Yi; Lin, Wen-Chiang

    2003-10-01

    A multi-functional sorbent is developed for the simultaneous removal of PbCl(2) vapor and sulfur dioxide from the combustion gases. The sorbent is tested in a bench-scale reactor at the temperature of 700 degrees C, using simulated flue gas (SFG) containing controlled amounts of PbCl(2) and SO(2) compounds. The removal characteristics of PbCl(2) and SO(2), individually and in combination, are investigated. The results show that the mechanism of capture by the sorbent is not a simple physical adsorption process but seems to involve a chemical reaction between the Ca-based sorbent and the contaminants from the simulated flue gas. The porous product layer in the case of individual SO(2) sorption is in a molten state at the reaction temperature. In contrast, the combined sorption of lead and sulfur compounds generates a flower-shaped polycrystalline product layer.

  14. Workforce development and effective evaluation of projects.

    PubMed

    Dickerson, Claire; Green, Tess; Blass, Eddie

    The success of a project or programme is typically determined in relation to outputs. However, there is a commitment among UK public services to spending public funds efficiently and on activities that provide the greatest benefit to society. Skills for Health recognised the need for a tool to manage the complex process of evaluating project benefits. An integrated evaluation framework was developed to help practitioners identify, describe, measure and evaluate the benefits of workforce development projects. Practitioners tested the framework on projects within three NHS trusts and provided valuable feedback to support its development. The prospective approach taken to identify benefits and collect baseline data to support evaluation was positively received and the clarity and completeness of the framework, as well as the relevance of the questions, were commended. Users reported that the framework was difficult to complete; an online version could be developed, which might help to improve usability. Effective implementation of this approach will depend on the quality and usability of the framework, the willingness of organisations to implement it, and the presence or establishment of an effective change management culture.

  15. Faculty Development for Educators: A Realist Evaluation

    ERIC Educational Resources Information Center

    Sorinola, Olanrewaju O.; Thistlethwaite, Jill; Davies, David; Peile, Ed

    2015-01-01

    The effectiveness of faculty development (FD) activities for educators in UK medical schools remains underexplored. This study used a realist approach to evaluate FD and to test the hypothesis that motivation, engagement and perception are key mechanisms of effective FD activities. The authors observed and interviewed 33 course participants at one…

  16. Developing and Evaluating Patient Education Materials.

    ERIC Educational Resources Information Center

    Monsivais, Diane; Reynolds, Audree

    2003-01-01

    Discusses the rationale for nurse involvement in the development of patient education materials. Presents guidelines for evaluating existing material, including print and web resources, for credibility and readability. Makes recommendations for rewriting material at an easier-to-read level. (SK)

  17. Evaluating the Impact of Human Resource Development.

    ERIC Educational Resources Information Center

    1999

    These four papers are from a symposium on evaluating the impact of human resource development (HRD). "Pre-Job Training and the Earnings of High-Tech Employees in Taiwan" (Tung-Chun Huang) reports on a study that concludes that public training programs have no impact on participants' earnings in later jobs, but participation in private training…

  18. Comparative study of the adsorption performance of a multi-sorbent bed (Carbotrap, Carbopack X, Carboxen 569) and a Tenax TA adsorbent tube for the analysis of volatile organic compounds (VOCs).

    PubMed

    Gallego, E; Roca, F J; Perales, J F; Guardino, X

    2010-05-15

    A comparison between two types of adsorbent tubes, the commonly used Tenax TA and a multi-sorbent bed (Carbotrap, Carbopack X, Carboxen 569) tube developed in our laboratory, has been done to evaluate their usefulness in the analysis of VOCs in ambient air. Duplicate indoor and outdoor samples of Tenax TA and multi-sorbent tubes of 10, 20, 40, 60 and 90l were taken in Barcelona city (Spain) on July and October of 2009. Breakthrough values (defined as %VOCs found in the back tube) were determined for all sampling volumes connecting two sampling tubes in series. The analysis was performed by automatic thermal desorption (ATD) coupled with capillary gas chromatography (GC)/mass spectrometry detector (MSD). Significant differences between the concentrations obtained-from multi-sorbent bed and Tenax TA tubes are observed for the very volatile compounds (56 degrees Csorbent bed than in Tenax TA tubes. On the other hand, mainly all compounds with boiling points higher than 100 degrees C (except alpha-pinene, chlorinated and polar compounds) do not show significant differences between the obtained multi-sorbent bed and Tenax TA tube concentrations. For the concentrations obtained (5ppt to 100ppb), Tenax TA present high breakthrough values (from 0 to 77%) for mainly all compounds and sampling volumes studied. On the other hand, multi-sorbent bed tubes do not exhibit important breakthrough values for these compounds, except the VVOCs ethanol (for all sampled volumes), and acetone, dichloromethane and isopropanol (for sampling volumes over 40l). The concentration differences observed between Tenax TA and multi-sorbent bed tubes are directly related

  19. The role of thermally induced fractures in the calcination and sulfation behavior of sorbents in fluidized bed combustion

    SciTech Connect

    Liu, Y.; Morrison, J.L.; Scaroni, A.W.

    1995-12-31

    In atmospheric pressure, circulating fluidized bed combustors, sorbents are used to minimize SO{sub 2} emissions. It is generally accepted that CaO, formed by decomposition of CaCO{sub 3}, reacts with SO{sub 2} and O{sub 2}: CaCO{sub 3} {yields} CaO + CO{sub 2} and CaO + SO{sub 2} + 1/2 O{sub 2} {yields} CaSO{sub 4} rather than direct sulfation of CaCO{sub 3}: CaCO{sub 3} + SO{sub 2} + 1/2 O{sub 2} {yields} CaSO{sub 4} + CO{sub 2}. Therefore, the physical structure of a calcine, e.g. pore size distribution, accessible surface area, plays an important role in subsequent sulfation behavior. While the use of sorbents to capture SO{sub 2} from combustion gases has been in practice for decades, experimental evaluation is still necessary for selecting a sorbent for a specific application. Naturally occurring sorbents, composed of individual grains of carbonate crystallites, vary greatly in their chemical composition and physical structure. The variation in sorbent properties is often reflected in calcination and sulfation behavior. The present work involved studying the effect of particle size and grain size on the sulfation behavior of six sorbents. The samples covered a wide range of chemical compositions (limestone to dolostone), physical strengths (low to high) and grain structures (fine to coarse-grained).

  20. Thermal activation of CaO-based sorbent and self-reactivation during CO{sub 2} capture looping cycles

    SciTech Connect

    Vasilije Manovic; Edward J. Anthony

    2008-06-01

    In this study, the thermal activation of different types of CaO-based sorbents was examined. Pretreatments were performed at different temperatures (800-1300{sup o}C) and different durations (6-48 h) using four Canadian limestones. Sieved fractions of the limestones, powders obtained by grinding, and hydroxides produced following multiple carbonation/calcination cycles achieved in a tube furnace were examined. Pretreated samples were evaluated using two types of thermogravimetric reactors/analyzers. The most important result was that thermal pretreatment could improve sorbent performance. In comparison to the original, pretreated sorbents showed better conversions over a longer series of CO{sub 2} cycles. Moreover, in some cases, sorbent activity actually increased with cycle number, and this effect was especially pronounced for powdered samples preheated at 1000{sup o}C. In these experiments, the increase of conversion with cycle number (designated as self-reactivation) after 30 cycles produced samples that were about 50% carbonated for the four sorbents examined here, and there appeared to be the potential for additional increase. These results were explained with the newly proposed pore-skeleton model. This model suggests, in addition to changes in the porous structure of the sorbent, that changes in the pore-skeleton produced during pretreatment strongly influence subsequent carbonation/calcination cycles. 31 refs., 8 figs.

  1. Thermal activation of CaO-based sorbent and self-reactivation during CO2 capture looping cycles.

    PubMed

    Manovic, Vasilije; Anthony, Edward J

    2008-06-01

    In this study, the thermal activation of different types of CaO-based sorbents was examined. Pretreatments were performed at different temperatures (800--1300 degrees C) and different durations (6--48 h) using four Canadian limestones. Sieved fractions of the limestones, powders obtained by grinding, and hydroxides produced following multiple carbonation/calcination cycles achieved in a tube furnace were examined. Pretreated samples were evaluated using two types of thermogravimetric reactors/ analyzers. The most important result was that thermal pretreatment could improve sorbent performance. In comparison to the original, pretreated sorbents showed better conversions over a longer series of CO2 cycles. Moreover, in some cases, sorbent activity actually increased with cycle number, and this effectwas especially pronounced for powdered samples preheated at 1000 degrees C. In these experiments, the increase of conversion with cycle number (designated as self-reactivation) after 30 cycles produced samples that were approximately 50% carbonated for the four sorbents examined here, and there appeared to be the potential for additional increase. These results were explained with the newly proposed pore--skeleton model. This model suggests, in addition to changes in the porous structure of the sorbent, that changes in the pore--skeleton produced during pretreatment strongly influence subsequent carbonation/ calcination cycles. PMID:18589983

  2. Novel nanoporous sorbent for solid-phase extraction in petroleum fingerprinting

    NASA Astrophysics Data System (ADS)

    Alayande, S. Oluwagbemiga; Hlengilizwe, Nyoni; Dare, E. Olugbenga; Msagati, Titus A. M.; Akinlabi, A. Kehinde; Aiyedun, P. O.

    2016-04-01

    Sample preparation is crucial in the analysis of petroleum and its derivatives. In this study, developing affordable sorbent for petroleum fingerprinting analysis using polymer waste such expanded polystyrene was explored. The potential of electrospun expanded polystyrene (EPS) as a sorbent for the solid-phase extraction (SPE) technique was investigated, and its efficiency was compared with commercial cartridges such as alumina, silica and alumina/silica hybrid commercial for petroleum fingerprinting analysis. The chromatograms showed that the packed electrospun EPS fibre demonstrated excellent properties for SPE applications relative to the hybrid cartridges.

  3. Waste-Heat-Driven Cooling Using Complex Compound Sorbents

    NASA Technical Reports Server (NTRS)

    Rocketfeller, Uwe; Kirol, Lance; Khalili, Kaveh

    2004-01-01

    Improved complex-compound sorption pumps are undergoing development for use as prime movers in heat-pump systems for cooling and dehumidification of habitats for humans on the Moon and for residential and commercial cooling on Earth. Among the advantages of sorption heat-pump systems are that they contain no moving parts except for check valves and they can be driven by heat from diverse sources: examples include waste heat from generation of electric power, solar heat, or heat from combustion of natural gas. The use of complex compound sorbents in cooling cycles is not new in itself: Marketing of residential refrigerators using SrCl2 was attempted in the 1920s and 30s and was abandoned because heat- and mass-transfer rates of the sorbents were too low. Addressing the issue that gave rise to the prior abandonment of complex compound sorption heat pumps, the primary accomplishment of the present development program thus far has been the characterization of many candidate sorption media, leading to large increases in achievable heat- and mass-transfer rates. In particular, two complex compounds (called "CC260-1260" and "CC260-2000") were found to be capable of functioning over the temperature range of interest for the lunar-habitat application and to offer heat- and mass-transfer rates and a temperature-lift capability adequate for that application. Regarding the temperature range: A heat pump based on either of these compounds is capable of providing a 95-K lift from a habitable temperature to a heat-rejection (radiator) temperature when driven by waste heat at an input temperature .500 K. Regarding the heat- and mass-transfer rates or, more precisely, the power densities made possible by these rates: Power densities observed in tests were 0.3 kilowatt of cooling per kilogram of sorbent and 2 kilowatts of heating per kilogram of sorbent. A prototype 1-kilowatt heat pump based on CC260-2000 has been built and demonstrated to function successfully.

  4. Development and evaluation of polybenzoxazole fibrous structures

    NASA Technical Reports Server (NTRS)

    Orndoff, Evelyne

    1995-01-01

    Woven and braided polybenzoxazole (PBO) structures have been developed for aerospace applications. The properties of PBO fibers are compared to those of other high performance fibers. PBO is unique for combining excellent flammability properties with the highest tensile strength and modulus of all synthetic organic fibers. The PBO structures are specifically developed to be compared to similar Kevlar structures. The physical, mechanical, thermal, and oxidative properties of the PBO woven and braided structures are determined. The resistance to various chemicals and to UV light is evaluated. Recommendations for specific aerospace applications are given with comments for further development and industrial applications.

  5. Environmental evaluation of subdivision site developments.

    PubMed

    Kaufman, Martin M; Wigston, David L; Perlman, Ellis B

    2002-06-01

    An environmental evaluation was performed at 16 subdivision sites within four communities in east-central Michigan. The primary objective was to evaluate the fit between environmental ordinances and the physical/environmental conditions to which they were applied. An environmental response index was developed with indicators to assess water, soil, slope, development density, roads, vegetation, and ecology. Water-related indicators achieved the highest scores, while soil-related indicators scored the poorest, with generally poor performance across all indicators. The poor performance indicates there are problems in the ability of environmental ordinances developed at broader jurisdictional scales (e.g., the state) to address the existing environmental conditions at smaller geographic scales (subdivisions within communities). Two key problems include the lack of scientific specificity in the broader state-level ordinances and the lack of local expertise and/or resources to monitor the environment. PMID:11992172

  6. Measurement and evaluation of sustainable development

    SciTech Connect

    Kondyli, Julia

    2010-11-15

    This paper develops a methodology to analyse, measure and evaluate sustainable development (SD). A holistic approach (systems analysis) is applied to operationalise the SD concept and an integrated approach (composite indicator construction) is adopted for the measurement of SD. The operationalisation of the SD concept is based on an in-depth systems analysis of issues associated with economic, social and environmental problems in a policy context. The composite indicator (overall sustainability index) is developed based on the three composite sub-indicators of the SD dimensions. The valuation of the SD is based both on the aggregated sub-indicators and the overall composite indicator. The methodology is used to evaluate the SD of the North Aegean islands between different temporal points. The assessment of the change in the islands' SD is based on a quartile grading scale of the overall SD composite scores.

  7. Environmental evaluation of subdivision site developments.

    PubMed

    Kaufman, Martin M; Wigston, David L; Perlman, Ellis B

    2002-06-01

    An environmental evaluation was performed at 16 subdivision sites within four communities in east-central Michigan. The primary objective was to evaluate the fit between environmental ordinances and the physical/environmental conditions to which they were applied. An environmental response index was developed with indicators to assess water, soil, slope, development density, roads, vegetation, and ecology. Water-related indicators achieved the highest scores, while soil-related indicators scored the poorest, with generally poor performance across all indicators. The poor performance indicates there are problems in the ability of environmental ordinances developed at broader jurisdictional scales (e.g., the state) to address the existing environmental conditions at smaller geographic scales (subdivisions within communities). Two key problems include the lack of scientific specificity in the broader state-level ordinances and the lack of local expertise and/or resources to monitor the environment.

  8. Manganese and Ceria Sorbents for High Temperature Sulfur Removal from Biomass-Derived Syngas -- The Impact of Steam on Capacity and Sorption Mode

    SciTech Connect

    Cheah, S.; Parent, Y. O.; Jablonski, W. S.; Vinzant, T.; Olstad, J. L.

    2012-07-01

    Syngas derived from biomass and coal gasification for fuel synthesis or electricity generation contains sulfur species that are detrimental to downstream catalysts or turbine operation. Sulfur removal in high temperature, high steam conditions has been known to be challenging, but experimental reports on methods to tackle the problem are not often reported. We have developed sorbents that can remove hydrogen sulfide from syngas at high temperature (700 C), both in dry and high steam conditions. The syngas composition chosen for our experiments is derived from statistical analysis of the gasification products of wood under a large variety of conditions. The two sorbents, Cu-ceria and manganese-based, were tested in a variety of conditions. In syngas containing steam, the capacity of the sorbents is much lower, and the impact of the sorbent in lowering H{sub 2}S levels is only evident in low space velocities. Spectroscopic characterization and thermodynamic consideration of the experimental results suggest that in syngas containing 45% steam, the removal of H{sub 2}S is primarily via surface chemisorptions. For the Cu-ceria sorbent, analysis of the amount of H{sub 2}S retained by the sorbent in dry syngas suggests both copper and ceria play a role in H{sub 2}S removal. For the manganese-based sorbent, in dry conditions, there is a solid state transformation of the sorbent, primarily into the sulfide form.

  9. Demonstration of dry carbon-based sorbent injection for mercury control in utility ESPs and baghouses

    SciTech Connect

    Sjostrom, S.; Smith, J.; Hunt, T.; Chang, R.; Brown, T.D.

    1997-12-31

    Domestic coal-fired power plants emit approximately 40 to 80 metric tons of mercury to the atmosphere annually, approximately 30% of all mercury emissions from human activities. However, the mercury concentration in utility flue gas is in the extremely dilute range of 0.1 to 1 part per billion. The EPA is assessing whether such low concentrations of mercury emissions from coal-fired utilities pose any significant health risk and whether mercury regulations would be necessary or appropriate. In anticipation of possible mercury control regulations, DOE has funded Public Service Company of Colorado (PSCo) to evaluate carbon-based sorbents for mercury control at utility coal-fired power plants. Initial investigations of the use of dry carbon-based sorbent injection for mercury control on utility applications have shown that carbon-based sorbents are capable of removing gaseous phase mercury. Because of the difficulty in capturing and measuring mercury, however, it is important to evaluate these technologies extensively on actual utility flue gas. Testing is currently underway on a slipstream of flue gas from PSCo`s Comanche Station in Pueblo, Colorado. The test fixture is a 600 acfm particulate control module that can be configured as an electrostatic precipitator, a pulse-jet baghouse, or a reverse-gas baghouse. Sorbent is injected into the flue gas slipstream prior to the particulate control module, and is removed by the module. Flue gas temperature and sorbent residence time can be changed to evaluate a range of plant operating conditions. In addition, the effect of fly ash on mercury capture can be evaluated because the flue gas slipstream can be taken from either upstream or downstream of Comanche Station`s full-scale reverse-gas baghouse. This paper describes the results of initial pilot testing in both an electrostatic precipitator and a pulse-jet baghouse.

  10. Biochar: a green sorbent to sequester acidic organic contaminants

    NASA Astrophysics Data System (ADS)

    Sigmund, Gabriel; Kah, Melanie; Sun, Huichao; Hofmann, Thilo

    2015-04-01

    Biochar is a carbon rich product of biomass pyrolysis that exhibits a high sorption potential towards a wide variety of inorganic and organic contaminants. Because it is a valuable soil additive and a potential carbon sink that can be produced from renewable resources, biochar has gained growing attention for the development of more sustainable remediation strategies. A lot of research efforts have been dedicated to the sorption of hydrophobic contaminants and metals to biochar. Conversely, the understanding of the sorption of acidic organic contaminants remains limited, and questions remain on the influence of biochar characteristics (e.g. ash content) on the sorption behaviour of acidic organic contaminants. To address this knowledge gap, sorption batch experiments were conducted with a series of structurally similar acidic organic contaminants covering a range of dissociation constant (2,4-D, MCPA, 2,4-DB and triclosan). The sorbents selected for experimentation included a series of 10 biochars covering a range of characteristics, multiwalled carbon nanotubes as model for pure carbonaceous phases, and an activated carbon as benchmark. Overall, sorption coefficient [L/kg] covered six orders of magnitude and generally followed the order 2,4-D < MCPA < 2,4-DB < triclosan. Combining comprehensive characterization of the sorbents with the sorption dataset allowed the discussion of sorption mechanisms and driving factors of sorption. Statistical analysis suggests that (i) partitioning was the main driver for sorption to sorbents with small specific surface area (< 25 m²/g), whereas (ii) specific mechanisms dominated sorption to sorbents with larger specific surface area. Results showed that factors usually not considered for the sorption of neutral contaminants play an important role for the sorption of organic acids. The pH dependent lipophilicity ratio (i.e. D instead of Kow), ash content and ionic strength are key factors influencing the sorption of acidic organic

  11. Sorbents for High Temperature Removal of Arsenic from Coal-Derived Synthesis Gas

    SciTech Connect

    Alptekin, G.O.; Copeland, R.; Dubovik, M.; Gershanovich, Y.

    2002-09-20

    Gasification technologies convert coal and other heavy feedstocks into synthesis gas feed streams that can be used in the production of a wide variety of chemicals, ranging from hydrogen through methanol, ammonia, acetic anhydride, dimethyl ether (DME), methyl tertiary butyl ether (MTBE), high molecular weight liquid hydrocarbons and waxes. Syngas can also be burned directly as a fuel in advanced power cycles to generate electricity with very high efficiency. However, the coal-derived synthesis gas contains a myriad of trace contaminants that may poison the catalysts that are used in the downstream manufacturing processes and may also be regulated in power plant emissions. Particularly, the catalysts used in the conversion of synthesis gas to methanol and other liquid fuels (Fischer-Tropsch liquids) have been found to be very sensitive to the low levels of poisons, especially arsenic, that are present in the synthesis gas from coal. TDA Research, Inc. (TDA) is developing an expendable high capacity, low-cost chemical absorbent to remove arsenic from coal-derived syngas. Unlike most of the commercially available sorbents that physically adsorb arsenic, TDA's sorbent operates at elevated temperatures and removes the arsenic through chemical reaction. The arsenic content in the coal gas stream is reduced to ppb levels with the sorbent by capturing and stabilizing the arsenic gas (As4) and arsenic hydrides (referred to as arsine, AsH3) in the solid state. To demonstrate the concept of high temperature arsenic removal from coal-derived syngas, we carried out bench-scale experiments to test the absorption capacity of a variety of sorbent formulations under representative conditions. Using on-line analysis techniques, we monitored the pre- and post-breakthrough arsine concentrations over different sorbent samples. Some of these samples exhibited pre-breakthrough arsine absorption capacity over 40% wt. (capacity is defined as lb of arsenic absorbed/lb of sorbent), while

  12. Arsenic removal using natural biomaterial-based sorbents.

    PubMed

    Ansone, Linda; Klavins, Maris; Viksna, Arturs

    2013-10-01

    Arsenic contamination of water is a major problem worldwide. A possible solution can be approached through developing new sorbents based on cost-effective and environmentally friendly natural biomaterials. We have developed new sorbents based on biomaterial impregnation with iron oxyhydroxide. In this study, raw peat material, iron-modified peat, iron-modified biomass (shingles, straw, sands, cane and moss) as well as iron humate were used for the removal of arsenate from contaminated water. The highest sorption capacity was observed in iron-modified peat, and kinetic studies indicated that the amount of arsenic sorbed on this material exceeds 90 % in 5 h. Arsenate sorption on iron-modified peat is characterised by the pseudo-second-order mechanism. The results of arsenic sorption in the presence of competing substances indicated that sulphate, nitrate, chloride and tartrate anions have practically no influence on As(V) sorption onto Fe-modified peat, whereas the presence of phosphate ions and humic acid significantly lowers the arsenic removal efficiency.

  13. Kinetics of Mn-based sorbents for hot coal gas desulfurization. Quarterly progress report, September 15, 1995--December 15, 1995

    SciTech Connect

    Hepworth, M.T.; Berns, J.

    1995-12-15

    The Morgantown Energy Technology Center (METC) of the U.S. Department of Energy (DOE) is actively pursuing the development of reliable and cost-effective processes to clean coal gasifier gases for application to integrated gasification combined cycle (IGCC) and molten carbonate fuel cell (MCFC) power plants. A large portion of gas cleanup research has been directed towards hot gas desulfurization using Zn-based sorbents. However, zinc titanate sorbents undergo reduction to the metal at temperatures approaching 700{degrees}C and lose reactivity because of volatilization. In addition, sulfate formation during regeneration leads to spalling of reactive surfaces. Because of these problems with zinc-based sorbents, METC has shown interest in formulating and testing manganese-based sorbents. Currently, many proposed IGCC processes include a water quench prior to desulfurization. This quench is required for two reasons; limitations in the process hardware (1000{degrees}C), and excessive Zn-based sorbent loss (about 700{degrees}C). With manganese, the water quench is not necessary to avoid sorbent loss, since Mn-based sorbents have been shown to retain reactivity under cyclic testing at 900{degrees}C. This advantage of manganese over zinc has potential to increase thermal efficiency as the trade-off of increasing the equilibrium H{sub 2}S over-pressure obtainable with a manganese sorbent. In the work which is reported here, lower loading temperatures (as low as 400{degrees}C) are studied. Also formulations containing titania rather then alumina are studied to attempt to improve performance.

  14. Desulfurization characteristics of rapidly hydrated sorbents with various adhesive carrier particles for a semidry CFB-FGD system.

    PubMed

    You, Changfu; Li, Yuan

    2013-03-19

    Semidry flue gas desulfurization (FGD) experiments were conducted using rapidly hydrated sorbents with four different adhesive carrier particles: circulation ash from a circulating fluidized bed boiler (CFBB circulation ash), fly ash from the first electrical field of the electrostatic precipitator of a circulating fluidized bed boiler (CFBB ESP ash), fly ash from a chain boiler (chain boiler ash), and river sand smaller than 1 mm. The influences of various adhesive carrier particles and operating conditions on the desulfurization characteristics of the sorbents were investigated, including sprayed water, reaction temperature, and the ratio of calcium to sulfur (Ca/S). The experimental results indicated that the rapidly hydrated sorbents had better desulfurization characteristics by using adhesive carrier particles which possessed better pore, adhesion, and fluidization characteristics. The desulfurization efficiency of the system increased as the reaction temperature decreased, it improved from 35% to 90% as the mass flow rate of the sprayed water increased from 0 to 10 kg/h, and it increased from 65.6% to 82.7% as Ca/S increased from 1.0 to 2.0. Based on these findings, a new semidry circulating fluidized bed (CFB)-FGD system using rapidly hydrated sorbent was developed. Using the rapidly hydrated sorbent, this system uses a cyclone separator instead of an ESP or a bag filter to recycle the sorbent particles, thereby decreasing the system flow resistance, saving investment and operating costs of the solids collection equipment.

  15. Hydrogen sulfide removal from coal gas by the metal-ferrite sorbents made from the heavy metal wastewater sludge.

    PubMed

    Tseng, Ting Ke; Chang, Han Ching; Chu, Hsin; Chen, Hung Ta

    2008-12-30

    The metal-ferrite (chromium-ferrite and zinc-ferrite) sorbents made from the heavy metal wastewater sludge have been developed for the hydrogen sulfide removal from coal gas. The high temperature absorption of hydrogen sulfide from coal gas with the metal-ferrite sorbent in a fixed bed reactor was conducted in this study. The metal-ferrite powders were the products of the ferrite process for the heavy metal wastewater treatment. The porosity analysis results show that the number of micropores of the sorbents after sulfidation and regeneration process decreases and the average pore size increases due to the acute endothermic and exothermic reactions during the sulfidation-regeneration process. The FeS, ZnS, and MnS peaks are observed on the sulfided sorbents, and the chromium extraction of the CFR6 can fulfill the emission standard of Taiwan EPA. The suitable sulfidation temperature range for chromium-ferrite sorbent is at 500-600 degrees C. In addition, effects of various concentrations of H2 and CO were also conducted in the present work at different temperatures. By increasing the H2 concentration, the sulfur sorption capacity of the sorbent decreases and an adverse result is observed in the case of increasing CO concentration. This can be explained via water-shift reaction.

  16. Desulfurization characteristics of rapidly hydrated sorbents with various adhesive carrier particles for a semidry CFB-FGD system.

    PubMed

    You, Changfu; Li, Yuan

    2013-03-19

    Semidry flue gas desulfurization (FGD) experiments were conducted using rapidly hydrated sorbents with four different adhesive carrier particles: circulation ash from a circulating fluidized bed boiler (CFBB circulation ash), fly ash from the first electrical field of the electrostatic precipitator of a circulating fluidized bed boiler (CFBB ESP ash), fly ash from a chain boiler (chain boiler ash), and river sand smaller than 1 mm. The influences of various adhesive carrier particles and operating conditions on the desulfurization characteristics of the sorbents were investigated, including sprayed water, reaction temperature, and the ratio of calcium to sulfur (Ca/S). The experimental results indicated that the rapidly hydrated sorbents had better desulfurization characteristics by using adhesive carrier particles which possessed better pore, adhesion, and fluidization characteristics. The desulfurization efficiency of the system increased as the reaction temperature decreased, it improved from 35% to 90% as the mass flow rate of the sprayed water increased from 0 to 10 kg/h, and it increased from 65.6% to 82.7% as Ca/S increased from 1.0 to 2.0. Based on these findings, a new semidry circulating fluidized bed (CFB)-FGD system using rapidly hydrated sorbent was developed. Using the rapidly hydrated sorbent, this system uses a cyclone separator instead of an ESP or a bag filter to recycle the sorbent particles, thereby decreasing the system flow resistance, saving investment and operating costs of the solids collection equipment. PMID:23398211

  17. Novel Sorbent to Clean Biogas for Fuel Cell Combined Heat and Power

    SciTech Connect

    2009-11-01

    TDA Research Inc., in collaboration with FuelCell Energy, will develop a new, high-capacity sorbent to remove sulfur from anaerobic digester gas. This technology will enable the production of a nearly sulfur-free biogas to replace natural gas in fuel cell power plants while reducing greenhouse gas emissions from fossil fuels.

  18. ACTIVATION AND REACTIVITY OF NOVEL CALCIUM-BASED SORBENTS FOR DRY SO2 CONTROL IN BOILERS

    EPA Science Inventory

    Chemically modified calcium hydroxide (Ca(OH)2) sorbents developed in the U.S. Environmental Protection Agency's Air and Energy Engineering Research Laboratory (AEERL) for sulfur dioxide (SO2) control in utility boilers were tested in an electrically heated, bench-scale isotherma...

  19. Layered solid sorbents for carbon dioxide capture

    SciTech Connect

    Li, Bingyun; Jiang, Bingbing; Gray, McMahan L; Fauth, Daniel J; Pennline, Henry W; Richards, George A

    2014-11-18

    A solid sorbent for the capture and the transport of carbon dioxide gas is provided having at least one first layer of a positively charged material that is polyethylenimine or poly(allylamine hydrochloride), that captures at least a portion of the gas, and at least one second layer of a negatively charged material that is polystyrenesulfonate or poly(acryclic acid), that transports the gas, wherein the second layer of material is in juxtaposition to, attached to, or crosslinked with the first layer for forming at least one bilayer, and a solid substrate support having a porous surface, wherein one or more of the bilayers is/are deposited on the surface of and/or within the solid substrate. A method of preparing and using the solid sorbent is provided.

  20. Oil removal from used sorbents using a biosurfactant.

    PubMed

    Wei, Q F; Mather, R R; Fotheringham, A F

    2005-02-01

    Oil spills impose serious damage on the environment. Mechanical recovery by the help of oil sorbents is one of the most important countermeasures in oil spill response. Most sorbents, however, end up in landfills or in incineration after a single use. These options either produce another source of pollution or increase the oil recovery cost. In this study a biosurfactant was used to clean used oil sorbents. This use of biosurfactants is new. Washing parameters tested included sorbent type, washing time, surfactant dosage and temperature. It was found that with biosurfactant washing more than 95% removal of the oil from sorbents was achieved, depending on the washing conditions. Biosurfactants were found to have considerable potential for recycling the used sorbents.

  1. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    SciTech Connect

    David A. Green; Brian S. Turk; Jeffrey W. Portzer; Raghubir P.Gupta; William J. McMichael; Ya Liang; Douglas P. Harrison

    2002-10-01

    The objective of this project is to develop a simple and inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable sorbent. The sorbents being investigated in this project are primarily alkali carbonates, and particularly sodium carbonate and potassium carbonate, which are converted to bicarbonates through reaction with carbon dioxide and water vapor. Bicarbonates are regenerated to carbonates when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. This quarter, electrobalance tests suggested that higher temperature calcination of trona leds to reduced carbonation activity in subsequent cycles, but that calcination in dry carbon dioxide did not result in decreased activity relative to calcination in helium. Following higher temperature calcination, sodium bicarbonate (SBC) No.3 has greater activity than either coarse or fine grades of trona. Fixed bed testing of calcined SBC No.3 at 70 C confirmed that high rates of carbon dioxide absorption are possible and that the resulting product is a mixture of Wegscheider's salt and sodium carbonate. In fluidized bed testing of supported potassium carbonate, very rapid carbonation rates were observed. Activity of the support material complicated the data analysis. A milled, spherical grade of SBC appeared to be similar in attrition and abrasion characteristics to an unmilled, less regularly shaped SBC. The calcination behavior, at 107 C, for the milled and unmilled materials was also similar.

  2. Sorbent suspensions vs. sorbent columns for extracorporeal detoxification in hepatic failure.

    PubMed

    Ash, Stephen R; Sullivan, Thomas A; Carr, David J

    2006-04-01

    Hepatic failure is a significant medical problem which has been unsuccessfully treated by hemodialysis. However, similar therapies using recirculated dialysate regenerated by sorbents in place of single-pass dialysate have been beneficial in treating acute-on-chronic liver failure. The advantages of sorbent-based treatments include some selectivity of toxin removal and improved removal of protein-bound toxins. Activated carbon has been extensively used in detoxification systems, but has often had insufficient toxin capacity. Powdered activated carbon, because of its large surface area, can provide greater binding capacity for bilirubin and other toxins than granular carbon commonly used in detoxifying columns. Methods of using powdered carbon in extracorporeal blood treatment devices are reviewed in the present paper, including liver dialysis and a new sorbent suspension reactor (SSR); and the abilities and limitations of the SSR and columns to process protein solutions are discussed. PMID:16684216

  3. Regenerable sorbent technique for capturing CO.sub.2 using immobilized amine sorbents

    DOEpatents

    Pennline, Henry W; Hoffman, James S; Gray, McMahan L; Fauth, Daniel J; Resnik, Kevin P

    2013-08-06

    The disclosure provides a CO.sub.2 absorption method using an amine-based solid sorbent for the removal of carbon dioxide from a gas stream. The method disclosed mitigates the impact of water loading on regeneration by utilizing a conditioner following the steam regeneration process, providing for a water loading on the amine-based solid sorbent following CO.sub.2 absorption substantially equivalent to the moisture loading of the regeneration process. This assists in optimizing the CO.sub.2 removal capacity of the amine-based solid sorbent for a given absorption and regeneration reactor size. Management of the water loading in this manner allows regeneration reactor operation with significant mitigation of energy losses incurred by the necessary desorption of adsorbed water.

  4. Evaluation of a nurse leadership development programme.

    PubMed

    West, Margaret; Smithgall, Lisa; Rosler, Greta; Winn, Erin

    2016-03-01

    The challenge for nursing leaders responsible for workforce planning is to predict the knowledge, skills and abilities required to lead future healthcare delivery systems effectively. Succession planning requires a constant, competitive pool of qualified nursing leader candidates, and retention of those interested in career growth. Formal nursing leadership education in the United States is available through graduate education and professional nursing organisation programmes, such as the Emerging Nurse Leader Institute of the American Organization of Nurse Executives. However, there is also a need for local development programmes tailored to the needs of individual organisations. Leaders at Geisinger Health System, one of the largest rural health systems in the US, identified the need for an internal professional development scheme for nurses. In 2013 the Nurses Emerging as Leaders programme was developed to prepare nurse leaders for effective leadership and successful role transition. This article describes the programme and an evaluation of its effectiveness. PMID:26927790

  5. Evaluation of a nurse leadership development programme.

    PubMed

    West, Margaret; Smithgall, Lisa; Rosler, Greta; Winn, Erin

    2016-03-01

    The challenge for nursing leaders responsible for workforce planning is to predict the knowledge, skills and abilities required to lead future healthcare delivery systems effectively. Succession planning requires a constant, competitive pool of qualified nursing leader candidates, and retention of those interested in career growth. Formal nursing leadership education in the United States is available through graduate education and professional nursing organisation programmes, such as the Emerging Nurse Leader Institute of the American Organization of Nurse Executives. However, there is also a need for local development programmes tailored to the needs of individual organisations. Leaders at Geisinger Health System, one of the largest rural health systems in the US, identified the need for an internal professional development scheme for nurses. In 2013 the Nurses Emerging as Leaders programme was developed to prepare nurse leaders for effective leadership and successful role transition. This article describes the programme and an evaluation of its effectiveness.

  6. Passive microwave algorithm development and evaluation

    NASA Technical Reports Server (NTRS)

    Petty, Grant W.

    1995-01-01

    The scientific objectives of this grant are: (1) thoroughly evaluate, both theoretically and empirically, all available Special Sensor Microwave Imager (SSM/I) retrieval algorithms for column water vapor, column liquid water, and surface wind speed; (2) where both appropriate and feasible, develop, validate, and document satellite passive microwave retrieval algorithms that offer significantly improved performance compared with currently available algorithms; and (3) refine and validate a novel physical inversion scheme for retrieving rain rate over the ocean. This report summarizes work accomplished or in progress during the first year of a three year grant. The emphasis during the first year has been on the validation and refinement of the rain rate algorithm published by Petty and on the analysis of independent data sets that can be used to help evaluate the performance of rain rate algorithms over remote areas of the ocean. Two articles in the area of global oceanic precipitation are attached.

  7. Evaluating innovation. Part 2: Development in neurosurgery.

    PubMed

    Schnurman, Zane; Kondziolka, Douglas

    2016-01-01

    OBJECT Patients, practitioners, payers, and regulators are advocating for reform in how medical advances are evaluated. Because surgery does not adhere to a standardized developmental pathway, how the medical community accepts a procedure remains unclear. The authors developed a new model, using publication data and patterns, that quantifies this process. Using this technique, the authors identified common archetypes and influences on neurosurgical progress from idea inception to acceptance. METHODS Seven neurosurgical procedures developed in the past 15-25 years were used as developmental case studies (endovascular coil, deep brain stimulation, vagus nerve stimulation, 1,3-bis(2-chloroethyl)-l-nitrosourea wafer, and 3 radiosurgery procedures), and the literature on each topic was evaluated. A new metric the authors termed "progressive scholarly acceptance" (PSA) was used as an end point for community acceptance. PSA was reached when the number of investigations that refine or improve a procedure eclipsed the total number of reports assessing initial efficacy. Report characteristics, including the number of patients studied, study design, and number of authoring groups from the first report to the point of PSA, were assessed. RESULTS Publication data implicated factors that had an outsized influence on acceptance. First, procedural accessibility to investigators was found to influence the number of reports, number of patients studied, and number of authoring groups contributing. Barriers to accessibility included target disease rarity, regulatory restrictions, and cost. Second, the ease or difficulty in applying a randomized controlled trial had an impact on study design. Based on these 2 factors, 3 developmental archetypes were characterized to generally describe the development of surgery. CONCLUSIONS Common surgical development archetypes can be described based on factors that impact investigative methods, data accumulation, and ultimate acceptance by society

  8. Evaluating innovation. Part 2: Development in neurosurgery.

    PubMed

    Schnurman, Zane; Kondziolka, Douglas

    2016-01-01

    OBJECT Patients, practitioners, payers, and regulators are advocating for reform in how medical advances are evaluated. Because surgery does not adhere to a standardized developmental pathway, how the medical community accepts a procedure remains unclear. The authors developed a new model, using publication data and patterns, that quantifies this process. Using this technique, the authors identified common archetypes and influences on neurosurgical progress from idea inception to acceptance. METHODS Seven neurosurgical procedures developed in the past 15-25 years were used as developmental case studies (endovascular coil, deep brain stimulation, vagus nerve stimulation, 1,3-bis(2-chloroethyl)-l-nitrosourea wafer, and 3 radiosurgery procedures), and the literature on each topic was evaluated. A new metric the authors termed "progressive scholarly acceptance" (PSA) was used as an end point for community acceptance. PSA was reached when the number of investigations that refine or improve a procedure eclipsed the total number of reports assessing initial efficacy. Report characteristics, including the number of patients studied, study design, and number of authoring groups from the first report to the point of PSA, were assessed. RESULTS Publication data implicated factors that had an outsized influence on acceptance. First, procedural accessibility to investigators was found to influence the number of reports, number of patients studied, and number of authoring groups contributing. Barriers to accessibility included target disease rarity, regulatory restrictions, and cost. Second, the ease or difficulty in applying a randomized controlled trial had an impact on study design. Based on these 2 factors, 3 developmental archetypes were characterized to generally describe the development of surgery. CONCLUSIONS Common surgical development archetypes can be described based on factors that impact investigative methods, data accumulation, and ultimate acceptance by society

  9. NASA RECON: Course Development, Administration, and Evaluation

    NASA Technical Reports Server (NTRS)

    Dominick, W. D.; Roquemore, L.

    1984-01-01

    The R and D activities addressing the development, administration, and evaluation of a set of transportable, college-level courses to educate science and engineering students in the effective use of automated scientific and technical information storage and retrieval systems, and, in particular, in the use of the NASA RECON system, are discussed. The long-range scope and objectives of these contracted activities are overviewed and the progress which has been made toward these objectives during FY 1983-1984 is highlighted. In addition, the results of a survey of 237 colleges and universities addressing course needs are presented.

  10. Sorbent Injection for Small ESP Mercury Control in Low Sulfur Eastern Bituminous Coal Flue Gas

    SciTech Connect

    Carl Richardson; Katherine Dombrowski; Douglas Orr

    2006-12-31

    This project Final Report is submitted to the U.S. Department of Energy (DOE) as part of Cooperative Agreement DE-FC26-03NT41987, 'Sorbent Injection for Small ESP Mercury Control in Low Sulfur Eastern Bituminous Coal Flue Gas.' Sorbent injection technology is targeted as the primary mercury control process on plants burning low/medium sulfur bituminous coals equipped with ESP and ESP/FGD systems. About 70% of the ESPs used in the utility industry have SCAs less than 300 ft2/1000 acfm. Prior to this test program, previous sorbent injection tests had focused on large-SCA ESPs. This DOE-NETL program was designed to generate data to evaluate the performance and economic feasibility of sorbent injection for mercury control at power plants that fire bituminous coal and are configured with small-sized electrostatic precipitators and/or an ESP-flue gas desulfurization (FGD) configuration. EPRI and Southern Company were co-funders for the test program. Southern Company and Reliant Energy provided host sites for testing and technical input to the project. URS Group was the prime contractor to NETL. ADA-ES and Apogee Scientific Inc. were sub-contractors to URS and was responsible for all aspects of the sorbent injection systems design, installation and operation at the different host sites. Full-scale sorbent injection for mercury control was evaluated at three sites: Georgia Power's Plant Yates Units 1 and 2 [Georgia Power is a subsidiary of the Southern Company] and Reliant Energy's Shawville Unit 3. Georgia Power's Plant Yates Unit 1 has an existing small-SCA cold-side ESP followed by a Chiyoda CT-121 wet scrubber. Yates Unit 2 is also equipped with a small-SCA ESP and a dual flue gas conditioning system. Unit 2 has no SO2 control system. Shawville Unit 3 is equipped with two small-SCA cold-side ESPs operated in series. All ESP systems tested in this program had SCAs less than 250 ft2/1000 acfm. Short-term parametric tests were conducted on Yates Units 1 and 2 to evaluate

  11. Clean Technology Evaluation & Workforce Development Program

    SciTech Connect

    Patricia Glaza

    2012-12-01

    The overall objective of the Clean Technology Evaluation portion of the award was to design a process to speed up the identification of new clean energy technologies and match organizations to testing and early adoption partners. The project was successful in identifying new technologies targeted to utilities and utility technology integrators, in developing a process to review and rank the new technologies, and in facilitating new partnerships for technology testing and adoption. The purpose of the Workforce Development portion of the award was to create an education outreach program for middle & high-school students focused on clean technology science and engineering. While originally targeting San Diego, California and Cambridge, Massachusetts, the scope of the program was expanded to include a major clean technology speaking series and expo as part of the USA Science & Engineering Festival on the National Mall in Washington, D.C.

  12. Development of instrumentation for magnetic nondestructive evaluation

    SciTech Connect

    Hariharan, S.

    1991-09-23

    The use of failure-prone components in critical applications has been traditionally governed by removing such components from service prior to the expiration of their predicted life expectancy. Such early retirement of materials does not guarantee that a particular sample will not fail in actual usage. The increasing cost of such life expectancy based operation and increased demand for improved reliability in industrial settings has necessitated an alternate form of quality control. Modern applications employ nondestructive evaluation (NDE), also known as nondestructive testing (NDT), as a means of monitoring the levels and growth of defects in a material throughout its operational life. This thesis describes the modifications made to existing instrumentation used for magnetic measurements at the Center for Nondestructive Evaluation at Iowa State University. Development of a new portable instrument is also given. An overview of the structure and operation of this instrumentation is presented. This thesis discusses the application of the magnetic hysteresis and Barkhausen measurement techniques, described in Sections 1.3.1 and 1.3.2 respectively, to a number of ferromagnetic specimens. Specifically, measurements were made on a number of railroad steel specimens for fatigue characterization, and on specimens of Damascus steel and Terfenol-D for materials evaluation. 60 refs., 51 figs., 5 tabs.

  13. The relative effectiveness of mineral-based sorbents for metal capture in a bench-scale incinerator

    SciTech Connect

    Carroll, G.J.; Venkatesh, S.

    1995-10-01

    Given the concern over the emission of hazardous constituent trace metals from incinerators, there is currently considerable interest in the potential use of mineral-based sorbents for capturing and retaining those metals in the incinerator {open_quotes}ash{close_quotes} discharges (fly ash and bottom ash). Most of the research completed to date has focussed on quantifying the effectiveness of various proposed sorbents for capturing vaporized metals from the flue gas. Other researchers have studied the incorporation of sorbents into the solid feed. This approach seeks to capture and bind the metals in the incinerator bottom ash, preventing them from exiting with the combustion gases. Research completed to date suggests that for this approach to be effective, the metal should become volatile in the incinerator environment and chemically react with the sorbent material. The subject test program was designed to further investigate this second approach by screening several minerals for their suitability as sorbent materials for capturing metals in the solid bed and preventing their release to the flue gas. In addition to capturing the metals, an ideal sorbent would retain them in the ash when disposed, so that extraction of the ash by the toxicity characteristic leaching procedure (TCLP) would yield a leachate with metals concentrations below respective regulatory levels. Accordingly, the objective of this screening program was to evaluate several candidate sorbents with respect to: (1) the degree to which they facilitate retention of trace metals in the ash/solid bed discharged from an incinerator; and (2) the degree to which they retain trace metals in the solid bed when subjected to TCLP extraction.

  14. Evaluation of developing inertial stabilization unit

    NASA Astrophysics Data System (ADS)

    Haruna, Masaki; Kodeki, Kazuhide; Shimizu, Seiichi; Fukushima, Kazuhiko; Takahara, Osamu; Ando, Toshiyuki; Suzuki, Jiro; Haraguchi, Eisuke

    2015-03-01

    Micro vibrations generated from some internal disturbance sources such as a reaction wheel degrades the pointing stability of an observation satellite. To suppress the pointing error, we have been developing an inertial stabilization unit. A prototype mechanism is designed based on concepts that it has non-contact actuators and sensors, and rotational leaf springs are applied to support a stabilized platform in order to meet two requirements which are precise drive and tolerance for launch load. Two kind of inertial sensors are installed on the platform to measure the attitude directly. Each of these two inertial sensors covers low or high bandwidth signal respectively. These signals will be able to be combined as one wideband signal to stabilize the platform in inertial space. In this paper, the developing prototype mechanism and control equipment are described and the basic evaluation results are reported. Less than 0.3urad as a drive precision and more than 100Hz as a local sensor control bandwidth are verified. The development of the system has not completely finished yet, but the basic performance is certified to meet the design specification. From now on, we continue to develop the unit. These future results can be applied to inter-satellite laser communication system.

  15. Poly(etheretherketone)-turnings a novel sorbent material for lead determination by flow injection flame atomic absorption spectrometry and factorial design optimization.

    PubMed

    Anthemidis, Aristidis N; Adam, Ibrahim S I; Zachariadis, George A

    2010-05-15

    A novel hydrophobic sorbent material for on-line column preconcentration and separation systems coupled with atomic spectrometry was developed. Poly(etheretherketone) (PEEK) in the form of turnings was used as packing material and evaluated for trace lead determination in environmental samples. Sample and ammonium diethyl-dithiophosphate (DDPA) reagent were mixed on-line and the Pb(II)-DDPA complex was retained effectively on PEEK-turnings. Isobutyl methyl ketone (IBMK) was adopted for efficient analyte complex elution and subsequently transportation into the nebulizer-burner system for atomization. The developed sorbent material has shown, excellent chemical and mechanical resistance, fast adsorption kinetics permitting the use of high sample flow rates without significant loss of retention efficiency. For 120s sample preconcentration time the sampling frequency was 20h(-1), the enhancement factor was 110, the detection limit (3s) was c(L)=0.32microgL(-1), and the relative standard deviation (RSD) was s(R)=2.2%, at the 50.0microgL(-1) Pb(II) level. The accuracy of the developed method was evaluated by analyzing certified reference materials. PMID:20298884

  16. Crosslinked polymeric ionic liquids as solid-phase microextraction sorbent coatings for high performance liquid chromatography.

    PubMed

    Yu, Honglian; Merib, Josias; Anderson, Jared L

    2016-03-18

    Neat crosslinked polymeric ionic liquid (PIL) sorbent coatings for solid-phase microextraction (SPME) compatible with high-performance liquid chromatography (HPLC) are reported for the first time. Six structurally different PILs were crosslinked to nitinol supports and applied for the determination of select pharmaceutical drugs, phenolics, and insecticides. Sampling conditions including sample solution pH, extraction time, desorption solvent, desorption time, and desorption solvent volume were optimized using design of experiment (DOE). The developed PIL sorbent coatings were stable when performing extractions under acidic pH and remained intact in various organic desorption solvents (i.e., methanol, acetonitrile, acetone). The PIL-based sorbent coating polymerized from the IL monomer 1-vinyl-3-(10-hydroxydecyl) imidazolium chloride [VC10OHIM][Cl] and IL crosslinker 1,12-di(3-vinylbenzylimidazolium) dodecane dichloride [(VBIM)2C12] 2[Cl] exhibited superior extraction performance compared to the other studied PILs. The extraction efficiency of pharmaceutical drugs and phenolics increased when the film thickness of the PIL-based sorbent coating was increased while many insecticides were largely unaffected. Satisfactory analytical performance was obtained with limits of detection (LODs) ranging from 0.2 to 2 μg L(-1) for the target analytes. The accuracy of the analytical method was examined by studying the relative recovery of analytes in real water samples, including tap water and lake water, with recoveries varying from 50.2% to 115.9% and from 48.8% to 116.6%, respectively. PMID:26896916

  17. Crosslinked polymeric ionic liquids as solid-phase microextraction sorbent coatings for high performance liquid chromatography.

    PubMed

    Yu, Honglian; Merib, Josias; Anderson, Jared L

    2016-03-18

    Neat crosslinked polymeric ionic liquid (PIL) sorbent coatings for solid-phase microextraction (SPME) compatible with high-performance liquid chromatography (HPLC) are reported for the first time. Six structurally different PILs were crosslinked to nitinol supports and applied for the determination of select pharmaceutical drugs, phenolics, and insecticides. Sampling conditions including sample solution pH, extraction time, desorption solvent, desorption time, and desorption solvent volume were optimized using design of experiment (DOE). The developed PIL sorbent coatings were stable when performing extractions under acidic pH and remained intact in various organic desorption solvents (i.e., methanol, acetonitrile, acetone). The PIL-based sorbent coating polymerized from the IL monomer 1-vinyl-3-(10-hydroxydecyl) imidazolium chloride [VC10OHIM][Cl] and IL crosslinker 1,12-di(3-vinylbenzylimidazolium) dodecane dichloride [(VBIM)2C12] 2[Cl] exhibited superior extraction performance compared to the other studied PILs. The extraction efficiency of pharmaceutical drugs and phenolics increased when the film thickness of the PIL-based sorbent coating was increased while many insecticides were largely unaffected. Satisfactory analytical performance was obtained with limits of detection (LODs) ranging from 0.2 to 2 μg L(-1) for the target analytes. The accuracy of the analytical method was examined by studying the relative recovery of analytes in real water samples, including tap water and lake water, with recoveries varying from 50.2% to 115.9% and from 48.8% to 116.6%, respectively.

  18. Retention behaviour of some high-intensity sweeteners on different SPE sorbents.

    PubMed

    Zygler, Agata; Wasik, Andrzej; Namieśnik, Jacek

    2010-10-15

    The objective of this paper is to provide information about application of solid-phase extraction (SPE) for isolation of nine high-intensity sweeteners (acesulfame-K, alitame, aspartame, cyclamate, dulcin, neotame, saccharin, sucralose and neohesperidin dihydrochalcone) from aqueous solutions. The influence of several types of LC-MS compatible buffers (different pH values and compositions) on their recovery has been studied and discussed. A number of commercially available SPE cartridges, such as Chromabond C18ec, Strata-X RP, Bakerbond Octadecyl, Bakerbond SDB-1, Bakerbond SPE Phenyl, Oasis HLB, LiChrolut RP-18, Supelclean LC-18, Discovery DSC-18 and Zorbax C18 were tested in order to evaluate their applicability for the isolation of analytes. Very high recoveries (better than 92%) of all studied compounds were obtained using formic acid-N,N-diisopropylethylamine buffer adjusted to pH 4.5 and C(18)-bonded silica sorbents. Behaviour of polymeric sorbents strongly depends on their structure. Strata-X RP behaves much like a C(18)-bonded silica sorbent. Recoveries obtained using Oasis HLB were comparable with those observed for silica-based sorbents. The only compound less efficiently (83%) retained by this sorbent was cyclamate. Bakerbond SDB-1 shows unusual selectivity towards aspartame and alitame. Recoveries of these two sweeteners were very low (26 and 42%, respectively). It was also found that aspartame and alitame can be selectively separated from the mixture of sweeteners using formic acid-triethylamine buffer at pH 3.5. PMID:20875571

  19. Design of a sorbent to enhance reactive adsorption of hydrogen sulfide.

    PubMed

    Wang, Long-Jiang; Fan, Hui-Ling; Shangguan, Ju; Croiset, Eric; Chen, Zhongwei; Wang, Hui; Mi, Jie

    2014-12-10

    A series of novel zinc oxide-silica composites with three-dimensionally ordered macropores (3DOM) structure were synthesized via colloidal crystal template method and used as sorbents for hydrogen sulfide (H2S) removal at room temperature for the first time. The performances of the prepared sorbents were evaluated by dynamic breakthrough testing. The materials were characterized before and after adsorption using scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). It was found that the composite with 3DOM structure exhibited remarkable desulfurization performance at room temperature and the enhancement of reactive adsorption of hydrogen sulfide was attributed to the unique structure features of 3DOM composites; high surface areas, nanocrystalline ZnO and the well-ordered interconnected macroporous with abundant mesopores. The introduction of silica could be conducive to support the 3DOM structure and the high dispersion of zinc oxide. Moisture in the H2S stream plays a crucial role in the removal process. The effects of Zn/Si ratio and the calcination temperature of 3DOM composites on H2S removal were studied. It demonstrated that the highest content of ZnO could reach up to 73 wt % and the optimum calcination temperature was 500 °C. The multiple adsorption/regeneration cycles showed that the 3DOM ZnO-SiO2 sorbent is stable and the sulfur capacity can still reach 67.4% of that of the fresh sorbent at the fifth cycle. These results indicate that 3DOM ZnO-SiO2 composites will be a promising sorbent for H2S removal at room temperature.

  20. Retention behaviour of some high-intensity sweeteners on different SPE sorbents.

    PubMed

    Zygler, Agata; Wasik, Andrzej; Namieśnik, Jacek

    2010-10-15

    The objective of this paper is to provide information about application of solid-phase extraction (SPE) for isolation of nine high-intensity sweeteners (acesulfame-K, alitame, aspartame, cyclamate, dulcin, neotame, saccharin, sucralose and neohesperidin dihydrochalcone) from aqueous solutions. The influence of several types of LC-MS compatible buffers (different pH values and compositions) on their recovery has been studied and discussed. A number of commercially available SPE cartridges, such as Chromabond C18ec, Strata-X RP, Bakerbond Octadecyl, Bakerbond SDB-1, Bakerbond SPE Phenyl, Oasis HLB, LiChrolut RP-18, Supelclean LC-18, Discovery DSC-18 and Zorbax C18 were tested in order to evaluate their applicability for the isolation of analytes. Very high recoveries (better than 92%) of all studied compounds were obtained using formic acid-N,N-diisopropylethylamine buffer adjusted to pH 4.5 and C(18)-bonded silica sorbents. Behaviour of polymeric sorbents strongly depends on their structure. Strata-X RP behaves much like a C(18)-bonded silica sorbent. Recoveries obtained using Oasis HLB were comparable with those observed for silica-based sorbents. The only compound less efficiently (83%) retained by this sorbent was cyclamate. Bakerbond SDB-1 shows unusual selectivity towards aspartame and alitame. Recoveries of these two sweeteners were very low (26 and 42%, respectively). It was also found that aspartame and alitame can be selectively separated from the mixture of sweeteners using formic acid-triethylamine buffer at pH 3.5.

  1. Anionic sorbents for arsenic and technetium species.

    SciTech Connect

    Lucero, Daniel A.; Moore, Robert Charles; Bontchev, Ranko Panayotov; Hasan, Ahmed Ali Mohamed; Zhao, Hongting; Salas, Fred Manuel; Holt, Kathleen Caroline

    2003-09-01

    Two sorbents, zirconium coated zeolite and magnesium hydroxide, were tested for their effectiveness in removing arsenic from Albuquerque municipal water. Results for the zirconium coated zeolite indicate that phosphate present in the water interfered with the sorption of arsenic. Additionally, there was a large quantity of iron and copper present in the water, corrosion products from the piping system, which may have interfered with the uptake of arsenic by the sorbent. Magnesium hydroxide has also been proven to be a strong sorbent for arsenic as well as other metals. Carbonate, present in water, has been shown to interfere with the sorption of arsenic by reacting with the magnesium hydroxide to form magnesium carbonate. The reaction mechanism was investigated by FT-IR and shows that hydrogen bonding between an oxygen on the arsenic species and a hydrogen on the Mg(OH)2 is most likely the mechanism of sorption. This was also confirmed by RAMAN spectroscopy and XRD. Technetium exists in multiple oxidation states (IV and VII) and is easily oxidized from the relatively insoluble Tc(IV) form to the highly water soluble and mobile Tc(VII) form. The two oxidation states exhibit different sorption characteristics. Tc(VII) does not sorb to most materials whereas Tc(IV) will strongly sorb to many materials. Therefore, it was determined that it is necessary to first reduce the Tc (using SnCl2) before sorption to stabilize Tc in the environment. Additionally, the effect of carbonate and phosphate on the sorption of technetium by hydroxyapatite was studied and indicated that both have a significant effect on reducing Tc sorption.

  2. Development and Evaluation of Titanium Spacesuit Bearings

    NASA Technical Reports Server (NTRS)

    Rhodes, Richard; Battisti, Brian; Ytuarte, Raymond, Jr.; Schultz, Bradley

    2016-01-01

    The Z-2 Prototype Planetary Extravehicular Space Suit Assembly is a continuation of NASA's Z-series of spacesuits, designed with the intent of meeting a wide variety of exploration mission objectives, including human exploration of the Martian surface. Incorporating titanium bearings into the Z-series space suit architecture allows us to reduce mass by an estimated 23 lbs per suit system compared to the previously used stainless steel bearing race designs, without compromising suit functionality. There are two obstacles to overcome when using titanium for a bearing race- 1) titanium is flammable when exposed to the oxygen wetted environment inside the space suit and 2) titanium's poor wear properties are often challenging to overcome in tribology applications. In order to evaluate the ignitability of a titanium space suit bearing, a series of tests were conducted at White Sands Test Facility (WSTF) that introduced the bearings to an extreme test profile, with multiple failures imbedded into the test bearings. The testing showed no signs of ignition in the most extreme test cases; however, substantial wear of the bearing races was observed. In order to design a bearing that can last an entire exploration mission (approx. 3 years), design parameters for maximum contact stress need to be identified. To identify these design parameters, bearing test rigs were developed that allow for the quick evaluation of various bearing ball loads, ball diameters, lubricants, and surface treatments. This test data will allow designers to minimize the titanium bearing mass for a specific material and lubricant combination and design around a cycle life requirement for an exploration mission. This paper reviews the current research and testing that has been performed on titanium bearing races to evaluate the use of such materials in an enriched oxygen environment and to optimize the bearing assembly mass and tribological properties to accommodate for the high bearing cycle life for an

  3. New high-capacity, calcium-based sorbents, calcium silicate sorbents. Final report, 1993--August 31, 1994

    SciTech Connect

    Kenney, M.C.; Chiang, R.K.; Fillgrove, K.L.

    1995-02-01

    A search is being carried out for new calcium-based S0{sub 2} sorbents for induct injection. More specifically, a search is being carried out for induct injection calcium silicate sorbents that are highly cost effective. The objectives for the current year include the study of sorbents made from Ca(OH){sub 2}, from mixtures of Ca(OH){sub 2} and SiO{sub 2}, and from portland cement. They also include the study of sorbents made from model compounds. During this year, sorbents prepared from Ca(OH){sub 2} and from mixtures of Ca(OH){sub 2} and fumed SiO{sub 2} were investigated. The results show that very good SiO{sub 2}-modified Ca(OH){sub 2} sorbents in which the Si-to-Ca reactant ratio is low can be prepared from Ca(OH){sub 2} and fumed SiO{sub 2}. Sorbents prepared from Ca(OH){sub 2} and natural SiO{sub 2} or natural SiO{sub 2} sources were also studied. The results obtained show that very good SiO{sub 2}-modified Ca(OH){sub 2} sorbents and calcium silicate hydrate sorbents, C-S-H sorbents, can be prepared from Ca(OH){sub 2} and diatomite, pumice or perlite, minerals that are readily available. In addition. sorbents prepared from Ca{sub 3}SiO{sub 5} and {beta}-Ca{sub 2}SiO{sub 4} and from mixtures of these compounds and SiO{sub 2} were studied. The results secured demonstrate that very good C-S-H rich sorbents can be prepared from these compounds and from mixtures of them with SiO{sub 2}. They also provide information useful for interpreting the cement sorbent results. Sorbents prepared from cement and from mixtures of cement and natural SiO{sub 2} or SiO{sub 2} sources were investigated as well. The results secured show that cement and mixtures of it with diatomite, pumice or perlite rapidly yield excellent sorbents with the proper reaction conditions.

  4. Improved Regenerative Sorbent-Compressor Refrigerator

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    1992-01-01

    Conceptual regenerative sorbent-compressor refrigerator attains regeneration efficiency and, therefore, overall power efficiency and performance greater than conventional refrigerators. Includes two fluid loops. In one, CH2FCF3 (R134a) ciculates by physical adsorption and desorption in four activated-charcoal sorption compressors. In other, liquid or gas coolant circulated by pump. Wave of regenerative heating and cooling propagates cyclically like peristatic wave among sorption compressors and associated heat exchangers. Powered by electricity, oil, gas, solar heat, or waste heat. Used as air conditioners, refrigerators, and heat pumps in industrial, home, and automotive applications.

  5. IODIDE AEROSOL SORBENTS FOR MERCURY CAPTURE IN COMBUSTION EXHAUSTS

    EPA Science Inventory

    Several sorbent processes are being studied for their feasibility for mercury capture. Mercury is different from the other heavy metals as it is not as chemically reactive (due to a filled outer electronic shell), thus making it difficult for sorbents to chemically trap it (a). ...

  6. Adsorption of sulfur(IV) oxide by amide sorbents

    SciTech Connect

    Nikandrov, I.S.; Kogtev, S.E.; Kazimirov, O.E.; Pavlova, I.V.

    1994-04-10

    Adsorption of sulfur(IV) oxide by industrial amide plastics has been studied. Sorption capacity of the sorbents studied has been determined under static and dynamic conditions. Physical and chemical interaction has been demonstrated to take place between sulfur(IV) oxide and the sorbent studied.

  7. Functionalized sorbent for chemical separations and sequential forming process

    DOEpatents

    Fryxell, Glen E.; Zemanian, Thomas S.

    2012-03-20

    A highly functionalized sorbent and sequential process for making are disclosed. The sorbent includes organic short-length amino silanes and organic oligomeric polyfunctional amino silanes that are dispersed within pores of a porous support that form a 3-dimensional structure containing highly functionalized active binding sites for sorption of analytes.

  8. 21 CFR 876.5870 - Sorbent hemoperfusion system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Sorbent hemoperfusion system. 876.5870 Section 876.5870 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5870 Sorbent...

  9. 21 CFR 876.5870 - Sorbent hemoperfusion system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Sorbent hemoperfusion system. 876.5870 Section 876.5870 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5870 Sorbent...

  10. 21 CFR 876.5870 - Sorbent hemoperfusion system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Sorbent hemoperfusion system. 876.5870 Section 876.5870 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5870 Sorbent...

  11. 21 CFR 876.5870 - Sorbent hemoperfusion system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Sorbent hemoperfusion system. 876.5870 Section 876.5870 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5870 Sorbent...

  12. Evaluation of population health short courses: implications for developing and evaluating population health professional development initiatives.

    PubMed

    Naccarella, Lucio; Greenstock, Louise; Butterworth, Iain

    2016-01-01

    Population health as an approach to planning is key to improving the health and well-being of whole populations and to reduce inequities within and between population groups. The Victorian Department of Health North and West Metropolitan Region, in collaboration with The University of Melbourne (School of Population Health), have delivered four annual population health short courses. The short courses were designed to equip participants with knowledge and skills to implement population health approaches upon their return to their workplaces. For three consecutive years, online surveys (n=41) and semi-structured interviews (n=35), underpinned by participatory and realist evaluation approaches, were conducted to obtain the perceptions and experiences of the population health short course participants. Evaluation findings indicate that participants' understanding of population health concepts increased; however, there were mixed outcomes in assisting participants' implementation of population health approaches upon their return to their workplaces. A core list of perceived requirements, enablers and barriers emerged at an individual, organisational and system level as influencing the capability of participants to implement population health approaches. Evaluation recommendations and actions taken to revise short course iterations are presented, providing evidence that the evaluation approaches were appropriate and increased the use of evaluation learnings. Implications of evaluation findings for professional development practice (i.e. shift from a 'Course' as a one-off event to a Population Health 'Program' of inter-dependent components) and evaluation (i.e. participatory realist evaluation approaches) are presented.

  13. Multi-component testing using HZ-PAN and AgZ-PAN Sorbents for OSPREY Model validation

    SciTech Connect

    Garn, Troy G.; Greenhalgh, Mitchell; Lyon, Kevin L.; Law, Jack D.

    2015-04-01

    In efforts to further develop the capability of the Off-gas SeParation and RecoverY (OSPREY) model, multi-component tests were completed using both HZ-PAN and AgZ-PAN sorbents. The primary purpose of this effort was to obtain multi-component xenon and krypton capacities for comparison to future OSPREY predicted multi-component capacities using previously acquired Langmuir equilibrium parameters determined from single component isotherms. Experimental capacities were determined for each sorbent using two feed gas compositions of 1000 ppmv xenon and 150 ppmv krypton in either a helium or air balance. Test temperatures were consistently held at 220 K and the gas flowrate was 50 sccm. Capacities were calculated from breakthrough curves using TableCurve® 2D software by Jandel Scientific. The HZ-PAN sorbent was tested in the custom designed cryostat while the AgZ-PAN was tested in a newly installed cooling apparatus. Previous modeling validation efforts indicated the OSPREY model can be used to effectively predict single component xenon and krypton capacities for both engineered form sorbents. Results indicated good agreement with the experimental and predicted capacity values for both krypton and xenon on the sorbents. Overall, the model predicted slightly elevated capacities for both gases which can be partially attributed to the estimation of the parameters and the uncertainty associated with the experimental measurements. Currently, OSPREY is configured such that one species adsorbs and one does not (i.e. krypton in helium). Modification of OSPREY code is currently being performed to incorporate multiple adsorbing species and non-ideal interactions of gas phase species with the sorbent and adsorbed phases. Once these modifications are complete, the sorbent capacities determined in the present work will be used to validate OSPREY multicomponent adsorption predictions.

  14. Developing Evaluation Capacity through Process Use

    ERIC Educational Resources Information Center

    King, Jean A.

    2007-01-01

    This article discusses how to make process use an independent variable in evaluation practice: the purposeful means of building an organization's capacity to conduct and use evaluations in the long run. The goal of evaluation capacity building (ECB) is to strengthen and sustain effective program evaluation practices through a number of activities:…

  15. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    SciTech Connect

    David A. Green; Brian S. Turk; Jeffrey W. Portzer; Thomas Nelson; Raghubir P. Gupta

    2005-01-01

    This report describes research conducted between October 1, 2004 and December 31, 2004 on the use of dry regenerable sorbents for removal of carbon dioxide from flue gas. Two supported sorbents were tested in a bench scale fluidized bed reactor system. The sorbents were prepared by impregnation of sodium carbonate on to an inert support at a commercial catalyst manufacturing facility. One sorbent, tested through five cycles of carbon dioxide sorption in an atmosphere of 3% water vapor and 0.8 to 3% carbon dioxide showed consistent reactivity with sodium carbonate utilization of 7 to 14%. A second, similarly prepared material, showed comparable reactivity in one cycle of testing. Batches of 5 other materials were prepared in laboratory scale quantities (primarily by spray drying). These materials generally have significantly greater surface areas than calcined sodium bicarbonate. Small scale testing showed no significant adsorption of mercury on representative carbon dioxide sorbent materials under expected flue gas conditions.

  16. Prototype demonstration of dual sorbent injection for acid gas control on municipal solid waste combustion units

    SciTech Connect

    1994-05-01

    This report gathered and evaluated emissions and operations data associated with furnace injection of dry hydrated lime and duct injection of dry sodium bicarbonate at a commercial, 1500 ton per day, waste-to-energy facility. The information compiled during the project sheds light on these sorbents to affect acid gas emissions from municipal solid waste combustors. The information assesses the capability of these systems to meet the 1990 Clean Air Act and 1991 EPA Emission Guidelines.

  17. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    SciTech Connect

    David A. Green; Thomas Nelson; Brian S. Turk; Paul Box; Weijiong Li; Raghubir P. Gupta

    2005-07-01

    This report describes research conducted between April 1, 2005 and June 30, 2005 on the use of dry regenerable sorbents for removal of carbon dioxide from flue gas from coal combustion and synthesis gas from coal gasification. Supported sodium carbonate sorbents removed up to 76% of the carbon dioxide from simulated flue gas in a downflow cocurrent flow reactor system, with an approximate 15 second gas-solid contact time. This reaction proceeds at temperatures as low as 25 C. Lithium silicate sorbents remove carbon dioxide from high temperature simulated flue gas and simulated synthesis gas. Both sorbent types can be thermally regenerated and reused. The lithium silicate sorbent was tested in a thermogravimetric analyzer and in a 1-in quartz reactor at atmospheric pressure; tests were also conducted at elevated pressure in a 2-in diameter high temperature high pressure reactor system. The lithium sorbent reacts rapidly with carbon dioxide in flue gas at 350-500 C to absorb about 10% of the sorbent weight, then continues to react at a lower rate. The sorbent can be essentially completely regenerated at temperatures above 600 C and reused. In atmospheric pressure tests with synthesis gas of 10% initial carbon dioxide content, the sorbent removed over 90% of the carbon dioxide. An economic analysis of a downflow absorption process for removal of carbon dioxide from flue gas with a supported sodium carbonate sorbent suggests that a 90% efficient carbon dioxide capture system installed at a 500 MW{sub e} generating plant would have an incremental capital cost of $35 million ($91/kWe, assuming 20 percent for contingencies) and an operating cost of $0.0046/kWh. Assuming capital costs of $1,000/kW for a 500 MWe plant the capital cost of the down flow absorption process represents a less than 10% increase, thus meeting DOE goals as set forth in its Carbon Sequestration Technology Roadmap and Program Plan.

  18. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    SciTech Connect

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Douglas P. Harrison; Ya Liang

    2001-10-01

    The objective of this project is to develop a simple, inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, ''baking soda,'' through reaction with carbon dioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. Testing conducted previously confirmed that the reaction rate and achievable CO{sub 2} capacity of sodium carbonate decreased with increasing temperature, and that the global rate of reaction of sodium carbonate to sodium bicarbonate increased with an increase in both CO{sub 2} and H{sub 2}O concentrations. Energy balance calculations indicated that the rate of heat removal from the particle surface may determine the reaction rate for a particular particle system. This quarter, thermogravimetric analyses (TGA) were conducted which indicated that calcination of sodium bicarbonate at temperatures as high as 200 C did not cause a significant decrease in activity in subsequent carbonation testing. When sodium bicarbonate was subjected to a five cycle calcination/carbonation test, activity declined slightly over the first two cycles but was constant thereafter. TGA tests were also conducted with two other potential sorbents. Potassium carbonate was found to be less active than sodium carbonate, at conditions of interest in preliminary TGA tests. Sodium carbonate monohydrate showed negligible activity. Testing was also conducted in a 2-inch internal diameter quartz fluidized-bed reactor system. A five cycle test demonstrated that initial removals of 10 to 15 percent of the carbon dioxide in a simulated flue gas could be achieved. The carbonation reaction proceeded at temperatures as low as 41 C. Future work by TGA and in fixed-bed, fluidized-bed, and transport

  19. Mechanistic and kinetic studies of high-temperature coal gas desulfurization sorbents. Final report, July 1988--July 1991

    SciTech Connect

    Lew, S.; Flytzani-Stephanopoulos, M.; Sarofim, A.F.

    1991-10-01

    The overall objective of this project was to investigate the properties of and evaluate mixed oxides of zinc and titanium for hot fuel gas desulfurization. Uncombined ZnO was also investigated as a base case. Detailed investigation of the reduction and sulfidation reactions of Zn-Ti-O sorbents was performed. The intrinsic kinetics and the product layer diffusion rates in reduction and sulfidation were determined. Kinetic experiments with sorbents containing various Zn/Ti atomic ratios were performed. Chemical phase and structural transformations were followed by various methods. The results were compared to similar experiments performed with ZnO. The purpose of these experiments was to determine how the presence of titanium dioxide affects the reduction and sulfidation of ZnO. This information would be used to identify and select the sorbent composition that gives the best combination of low reduction rate and acceptable sulfidation performance at temperatures exceeding 600{degree}C. (VC)

  20. The Process of Evaluation in Rural Development.

    ERIC Educational Resources Information Center

    Wetherill, G. Richard

    Program evaluation can be used for both program improvement and program justification, and it can aid in program planning and policy making. In evaluation, we must be concerned with the components which not only make up the program but also the evaluation such as program objectives or goals, program personnel interaction, program processes,…