Science.gov

Sample records for co2 separation capture

  1. Evaluation of Mars CO2 Capture and Gas Separation Technologies

    NASA Technical Reports Server (NTRS)

    Muscatello, Anthony C.; Santiago-Maldonado, Edgardo; Gibson, Tracy; Devor, Robert; Captain, James

    2011-01-01

    Recent national policy statements have established that the ultimate destination of NASA's human exploration program is Mars. In Situ Resource Utilization (ISRU) is a key technology required to ,enable such missions and it is appropriate to review progress in this area and continue to advance the systems required to produce rocket propellant, oxygen, and other consumables on Mars using the carbon dioxide atmosphere and other potential resources. The Mars Atmospheric Capture and Gas separation project is selecting, developing, and demonstrating techniques to capture and purify Martian atmospheric gases for their utilization for the production of hydrocarbons, oxygen, and water in ISRU systems. Trace gases will be required to be separated from Martian atmospheric gases to provide pure CO2 to processing elements. In addition, other Martian gases, such as nitrogen and argon, occur in concentrations high enough to be useful as buffer gas and should be captured as well. To achieve these goals, highly efficient gas separation processes will be required. These gas separation techniques are also required across various areas within the ISRU project to support various consumable production processes. The development of innovative gas separation techniques will evaluate the current state-of-the-art for the gas separation required, with the objective to demonstrate and develop light-weight, low-power methods for gas separation. Gas separation requirements include, but are not limited to the selective separation of: (1) methane and water from unreacted carbon oxides (C02-CO) and hydrogen typical of a Sabatier-type process, (2) carbon oxides and water from unreacted hydrogen from a Reverse Water-Gas Shift process, (3)/carbon oxides from oxygen from a trash/waste processing reaction, and (4) helium from hydrogen or oxygen from a propellant scavenging process. Potential technologies for the separations include' freezers, selective membranes, selective solvents, polymeric sorbents

  2. Computational investigation of thermal gas separation for CO2 capture.

    SciTech Connect

    Gallis, Michail A.; Bryan, Charles R.; Brady, Patrick Vane; Torczynski, John Robert; Brooks, Carlton, F.

    2009-09-01

    This report summarizes the work completed under the Laboratory Directed Research and Development (LDRD) project 09-1351, 'Computational Investigation of Thermal Gas Separation for CO{sub 2} Capture'. Thermal gas separation for a binary mixture of carbon dioxide and nitrogen is investigated using the Direct Simulation Monte Carlo (DSMC) method of molecular gas dynamics. Molecular models for nitrogen and carbon dioxide are developed, implemented, compared to theoretical results, and compared to several experimental thermophysical properties. The molecular models include three translational modes, two fully excited rotational modes, and vibrational modes, whose degree of excitation depends on the temperature. Nitrogen has one vibrational mode, and carbon dioxide has four vibrational modes (two of which are degenerate). These models are used to perform a parameter study for mixtures of carbon dioxide and nitrogen confined between parallel walls over realistic ranges of gas temperatures and nominal concentrations of carbon dioxide. The degree of thermal separation predicted by DSMC is slightly higher than experimental values and is sensitive to the details of the molecular models.

  3. CO2 Capture Using Electrical Energy: Electrochemically Mediated Separation for Carbon Capture and Mitigation

    SciTech Connect

    2010-07-16

    IMPACCT Project: MIT and Siemens Corporation are developing a process to separate CO2 from the exhaust of coal-fired power plants by using electrical energy to chemically activate and deactivate sorbents, or materials that absorb gases. The team found that certain sorbents bond to CO2 when they are activated by electrical energy and then transported through a specialized separator that deactivates the molecule and releases it for storage. This method directly uses the electricity from the power plant, which is a more efficient but more expensive form of energy than heat, though the ease and simplicity of integrating it into existing coal-fired power plants reduces the overall cost of the technology. This process could cost as low as $31 per ton of CO2 stored.

  4. CO2 CAPTURE PROJECT - AN INTEGRATED, COLLABORATIVE TECHNOLOGY DEVELOPMENT PROJECT FOR NEXT GENERATION CO2 SEPARATION, CAPTURE AND GEOLOGIC SEQUESTRATION

    SciTech Connect

    Dr. Helen Kerr

    2003-08-01

    The CO{sub 2} Capture Project (CCP) is a joint industry project, funded by eight energy companies (BP, ChevronTexaco, EnCana, Eni, Norsk Hydro, Shell, Statoil, and Suncor) and three government agencies (1) European Union (DG Res & DG Tren), (2) Norway (Klimatek) and (3) the U.S.A. (Department of Energy). The project objective is to develop new technologies, which could reduce the cost of CO{sub 2} capture and geologic storage by 50% for retrofit to existing plants and 75% for new-build plants. Technologies are to be developed to ''proof of concept'' stage by the end of 2003. The project budget is approximately $24 million over 3 years and the work program is divided into eight major activity areas: (1) Baseline Design and Cost Estimation--defined the uncontrolled emissions from each facility and estimate the cost of abatement in $/tonne CO{sub 2}. (2) Capture Technology, Post Combustion: technologies, which can remove CO{sub 2} from exhaust gases after combustion. (3) Capture Technology, Oxyfuel: where oxygen is separated from the air and then burned with hydrocarbons to produce an exhaust with high CO{sub 2} for storage. (4) Capture Technology, Pre -Combustion: in which, natural gas and petroleum coke are converted to hydrogen and CO{sub 2} in a reformer/gasifier. (5) Common Economic Model/Technology Screening: analysis and evaluation of each technology applied to the scenarios to provide meaningful and consistent comparison. (6) New Technology Cost Estimation: on a consistent basis with the baseline above, to demonstrate cost reductions. (7) Geologic Storage, Monitoring and Verification (SMV): providing assurance that CO{sub 2} can be safely stored in geologic formations over the long term. (8) Non-Technical: project management, communication of results and a review of current policies and incentives governing CO{sub 2} capture and storage. Technology development work dominated the past six months of the project. Numerous studies are making substantial progress

  5. Dynamic Entangled Porous Framework for Hydrocarbon (C2-C3) Storage, CO2 Capture, and Separation.

    PubMed

    Sikdar, Nivedita; Bonakala, Satyanarayana; Haldar, Ritesh; Balasubramanian, Sundaram; Maji, Tapas Kumar

    2016-04-18

    Storage and separation of small (C1-C3) hydrocarbons are of great significance as these are alternative energy resources and also can be used as raw materials for many industrially important materials. Selective capture of greenhouse gas, CO2 from CH4 is important to improve the quality of natural gas. Among the available porous materials, MOFs with permanent porosity are the most suitable to serve these purposes. Herein, a two-fold entangled dynamic framework {[Zn2 (bdc)2 (bpNDI)]⋅4DMF}n with pore surface carved with polar functional groups and aromatic π clouds is exploited for selective capture of CO2 , C2, and C3 hydrocarbons at ambient condition. The framework shows stepwise CO2 and C2 H2 uptake at 195 K but type I profiles are observed at 298 K. The IAST selectivity of CO2 over CH4 is the highest (598 at 298 K) among the MOFs without open metal sites reported till date. It also shows high selectivity for C2 H2 , C2 H4 , C2 H6 , and C3 H8 over CH4 at 298 K. DFT calculations reveal that aromatic π surface and the polar imide (RNC=O) functional groups are the primary adsorption sites for adsorption. Furthermore, breakthrough column experiments showed CO2 /CH4 C2 H6 /CH4 and CO2 /N2 separation capability at ambient condition. PMID:26973086

  6. CO2 Capture Project: An Integrated, Collaborative Technology Development Project For CO2 Separation, Capture And Geologic Sequestration

    SciTech Connect

    Helen Kerr

    2002-01-10

    This report (which forms part of the requirements of the Statement of Work Task 0, subtask 0.4) records progress towards defining a detailed Work Plan for the CCP 30 days after contract initiation. It describes the studies planned, workscope development and technology provider bid evaluation status at that time. Business sensitive information is provided separately in Appendix 1. Contract negotiations are on hold pending award of patent waiver status to the CCP.

  7. Porous materials as high performance adsorbents for CO2 capture, gas separation and purification

    NASA Astrophysics Data System (ADS)

    Wang, Jun

    Global warming resulted from greenhouse gases emission has received a widespread attention. Among the greenhouse gases, CO2 contributes more than 60% to global warming due to its huge emission amount. The flue gas contains about 15% CO2 with N2 as the balance. If CO2 can be separated from flue gas, the benefit is not only reducing the global warming effect, but also producing pure CO2 as a very useful industry raw material. Substantial progress is urgent to be achieved in an industrial process. Moreover, energy crisis is one of the biggest challenges for all countries due to the short life of fossil fuels, such as, petroleum will run out in 50 years and coal will run out in 150 years according to today's speed. Moreover, the severe pollution to the environment caused by burning fossil fuels requires us to explore sustainable, environment-friendly, and facile energy sources. Among several alternative energy sources, natural gas is one of the most promising alternative energy sources due to its huge productivity, abundant feed stock, and ease of generation. In order to realize a substantial adsorption process in industry, synthesis of new adsorbents or modification of existing adsorbent with improved properties has become the most critical issue. This dissertation reports systemic characterization and development of five serials of novel adsorbents with advanced adsorption properties. In chapter 2, nitrogen-doped Hypercross-linking Polymers (HCPs) have been synthesized successfully with non-carcinogenic chloromethyl methyl ether (CME) as the cross-linking agent within a single step. Texture properties, surface morphology, CO2/N2 selectivity, and adsorption heat have been presented and demonstrated properly. A comprehensive discussion on factors that affect the CO2 adsorption and CO2/N 2 separation has also been presented. It was found that high micropore proportion and N-content could effectively enhance CO2 uptake and CO2/N2 separation selectivity. In chapter 3, a

  8. Geological Sequestration Training and Research Program in Capture and Transport: Development of the Most Economical Separation Method for CO2 Capture

    SciTech Connect

    Vahdat, Nader

    2013-09-30

    The project provided hands-on training and networking opportunities to undergraduate students in the area of carbon dioxide (CO2) capture and transport, through fundamental research study focused on advanced separation methods that can be applied to the capture of CO2 resulting from the combustion of fossil-fuels for power generation . The project team’s approach to achieve its objectives was to leverage existing Carbon Capture and Storage (CCS) course materials and teaching methods to create and implement an annual CCS short course for the Tuskegee University community; conduct a survey of CO2 separation and capture methods; utilize data to verify and develop computer models for CO2 capture and build CCS networks and hands-on training experiences. The objectives accomplished as a result of this project were: (1) A comprehensive survey of CO2 capture methods was conducted and mathematical models were developed to compare the potential economics of the different methods based on the total cost per year per unit of CO2 avoidance; and (2) Training was provided to introduce the latest CO2 capture technologies and deployment issues to the university community.

  9. Porous materials as high performance adsorbents for CO2 capture, gas separation and purification

    NASA Astrophysics Data System (ADS)

    Wang, Jun

    Global warming resulted from greenhouse gases emission has received a widespread attention. Among the greenhouse gases, CO2 contributes more than 60% to global warming due to its huge emission amount. The flue gas contains about 15% CO2 with N2 as the balance. If CO2 can be separated from flue gas, the benefit is not only reducing the global warming effect, but also producing pure CO2 as a very useful industry raw material. Substantial progress is urgent to be achieved in an industrial process. Moreover, energy crisis is one of the biggest challenges for all countries due to the short life of fossil fuels, such as, petroleum will run out in 50 years and coal will run out in 150 years according to today's speed. Moreover, the severe pollution to the environment caused by burning fossil fuels requires us to explore sustainable, environment-friendly, and facile energy sources. Among several alternative energy sources, natural gas is one of the most promising alternative energy sources due to its huge productivity, abundant feed stock, and ease of generation. In order to realize a substantial adsorption process in industry, synthesis of new adsorbents or modification of existing adsorbent with improved properties has become the most critical issue. This dissertation reports systemic characterization and development of five serials of novel adsorbents with advanced adsorption properties. In chapter 2, nitrogen-doped Hypercross-linking Polymers (HCPs) have been synthesized successfully with non-carcinogenic chloromethyl methyl ether (CME) as the cross-linking agent within a single step. Texture properties, surface morphology, CO2/N2 selectivity, and adsorption heat have been presented and demonstrated properly. A comprehensive discussion on factors that affect the CO2 adsorption and CO2/N 2 separation has also been presented. It was found that high micropore proportion and N-content could effectively enhance CO2 uptake and CO2/N2 separation selectivity. In chapter 3, a

  10. CO2 Capture Project-An Integrated, Collaborative Technology Development Project for Next Generation CO2 Separation, Capture and Geologic Sequestration

    SciTech Connect

    Helen Kerr; Linda M. Curran

    2005-04-15

    The CO{sub 2} Capture Project (CCP) was a joint industry project, funded by eight energy companies (BP, ChevronTexaco, EnCana, ENI, Norsk Hydro, Shell, Statoil, and Suncor) and three government agencies (European Union [DG RES & DG TREN], the Norwegian Research Council [Klimatek Program] and the U.S. Department of Energy [NETL]). The project objective was to develop new technologies that could reduce the cost of CO{sub 2} capture and geologic storage by 50% for retrofit to existing plants and 75% for new-build plants. Technologies were to be developed to ''proof of concept'' stage by the end of 2003. Certain promising technology areas were increased in scope and the studies extended through 2004. The project budget was approximately $26.4 million over 4 years and the work program is divided into eight major activity areas: Baseline Design and Cost Estimation--defined the uncontrolled emissions from each facility and estimate the cost of abatement in $/tonne CO{sub 2}. Capture Technology, Post Combustion: technologies, which can remove CO{sub 2} from exhaust gases after combustion. Capture Technology, Oxyfuel: where oxygen is separated from the air and then burned with hydrocarbons to produce an exhaust with high CO{sub 2} for storage. Capture Technology, Pre-Combustion: in which, natural gas and petroleum cokes are converted to hydrogen and CO{sub 2} in a reformer/gasifier. Common Economic Model/Technology Screening: analysis and evaluation of each technology applied to the scenarios to provide meaningful and consistent comparison. New Technology Cost Estimation: on a consistent basis with the baseline above, to demonstrate cost reductions. Geologic Storage, Monitoring and Verification (SMV): providing assurance that CO{sub 2} can be safely stored in geologic formations over the long term. Non-Technical: project management, communication of results and a review of current policies and incentives governing CO{sub 2} capture and storage. Pre-combustion De

  11. CO2 CAPTURE PROJECT-AN INTEGRATED, COLLABORATIVE TECHNOLOGY DEVELOPMENT PROJECT FOR NEXT GENERATION CO2 SEPARATION, CAPTURE AND GEOLOGIC SEQUESTRATION

    SciTech Connect

    Helen Kerr

    2004-04-01

    The CO{sub 2} Capture Project (CCP) is a joint industry project, funded by eight energy companies (BP, ChevronTexaco, EnCana, Eni, Norsk Hydro, Shell, Statoil, and Suncor) and three government agencies (European Union (DG Res & DG Tren), Norway (Klimatek) and the U.S.A. (Department of Energy)). The project objective is to develop new technologies, which could reduce the cost of CO{sub 2} capture and geologic storage by 50% for retrofit to existing plants and 75% for new-build plants. Technologies are to be developed to ''proof of concept'' stage by the end of 2003. The project budget is approximately $24 million over 3 years and the work program is divided into eight major activity areas: (1) Baseline Design and Cost Estimation--defined the uncontrolled emissions from each facility and estimate the cost of abatement in $/tonne CO{sub 2}. (2) Capture Technology, Post Combustion--technologies, which can remove CO{sub 2} from exhaust gases after combustion. (3) Capture Technology, Oxyfuel--where oxygen is separated from the air and then burned with hydrocarbons to produce an exhaust with wet high concentrations of CO{sub 2} for storage. (4) Capture Technology, Pre-Combustion--in which, natural gas and petroleum coke are converted to hydrogen and CO{sub 2} in a reformer/gasifier. (5) Common Economic Model/Technology Screening--analysis and evaluation of each technology applied to the scenarios to provide meaningful and consistent comparison. (6) New Technology Cost Estimation: on a consistent basis with the baseline above, to demonstrate cost reductions. (7) Geologic Storage, Monitoring and Verification (SMV)--providing assurance that CO{sub 2} can be safely stored in geologic formations over the long term. (8) Non-Technical: project management, communication of results and a review of current policies and incentives governing CO{sub 2} capture and storage. Technology development work dominated the past six months of the project. Numerous studies have completed their

  12. Capturing CO2 via reactions in nanopores.

    SciTech Connect

    Leung, Kevin; Nenoff, Tina Maria; Criscenti, Louise Jacqueline; Tang, Z; Dong, J. H.

    2008-10-01

    This one-year exploratory LDRD aims to provide fundamental understanding of the mechanism of CO2 scrubbing platforms that will reduce green house gas emission and mitigate the effect of climate change. The project builds on the team member's expertise developed in previous LDRD projects to study the capture or preferential retention of CO2 in nanoporous membranes and on metal oxide surfaces. We apply Density Functional Theory and ab initio molecular dynamics techniques to model the binding of CO2 on MgO and CaO (100) surfaces and inside water-filled, amine group functionalized silica nanopores. The results elucidate the mechanisms of CO2 trapping and clarify some confusion in the literature. Our work identifies key future calculations that will have the greatest impact on CO2 capture technologies, and provides guidance to science-based design of platforms that can separate the green house gas CO2 from power plant exhaust or even from the atmosphere. Experimentally, we modify commercial MFI zeolite membranes and find that they preferentially transmit H2 over CO2 by a factor of 34. Since zeolite has potential catalytic capability to crack hydrocarbons into CO2 and H2, this finding paves the way for zeolite membranes that can convert biofuel into H2 and separate the products all in one step.

  13. Separation and capture of CO2 from large stationary sources and sequestration in geological formations--coalbeds and deep saline aquifers.

    PubMed

    White, Curt M; Strazisar, Brian R; Granite, Evan J; Hoffman, James S; Pennline, Henry W

    2003-06-01

    The topic of global warming as a result of increased atmospheric CO2 concentration is arguably the most important environmental issue that the world faces today. It is a global problem that will need to be solved on a global level. The link between anthropogenic emissions of CO2 with increased atmospheric CO2 levels and, in turn, with increased global temperatures has been well established and accepted by the world. International organizations such as the United Nations Framework Convention on Climate Change (UNFCCC) and the Intergovernmental Panel on Climate Change (IPCC) have been formed to address this issue. Three options are being explored to stabilize atmospheric levels of greenhouse gases (GHGs) and global temperatures without severely and negatively impacting standard of living: (1) increasing energy efficiency, (2) switching to less carbon-intensive sources of energy, and (3) carbon sequestration. To be successful, all three options must be used in concert. The third option is the subject of this review. Specifically, this review will cover the capture and geologic sequestration of CO2 generated from large point sources, namely fossil-fuel-fired power gasification plants. Sequestration of CO2 in geological formations is necessary to meet the President's Global Climate Change Initiative target of an 18% reduction in GHG intensity by 2012. Further, the best strategy to stabilize the atmospheric concentration of CO2 results from a multifaceted approach where sequestration of CO2 into geological formations is combined with increased efficiency in electric power generation and utilization, increased conservation, increased use of lower carbon-intensity fuels, and increased use of nuclear energy and renewables. This review covers the separation and capture of CO2 from both flue gas and fuel gas using wet scrubbing technologies, dry regenerable sorbents, membranes, cryogenics, pressure and temperature swing adsorption, and other advanced concepts. Existing

  14. Covalent Organic Frameworks for CO2 Capture.

    PubMed

    Zeng, Yongfei; Zou, Ruqiang; Zhao, Yanli

    2016-04-01

    As an emerging class of porous crystalline materials, covalent organic frameworks (COFs) are excellent candidates for various applications. In particular, they can serve as ideal platforms for capturing CO2 to mitigate the dilemma caused by the greenhouse effect. Recent research achievements using COFs for CO2 capture are highlighted. A background overview is provided, consisting of a brief statement on the current CO2 issue, a summary of representative materials utilized for CO2 capture, and an introduction to COFs. Research progresses on: i) experimental CO2 capture using different COFs synthesized based on different covalent bond formations, and ii) computational simulation results of such porous materials on CO2 capture are summarized. Based on these experimental and theoretical studies, careful analyses and discussions in terms of the COF stability, low- and high-pressure CO2 uptake, CO2 selectivity, breakthrough performance, and CO2 capture conditions are provided. Finally, a perspective and conclusion section of COFs for CO2 capture is presented. Recent advancements in the field are highlighted and the strategies and principals involved are discussed. PMID:26924720

  15. CAPTURING CO2 WITH MGO AEROGELS

    EPA Science Inventory

    CO2 capture from flue gas requires that the adsorbent be active at relatively low CO2 concentrations (3 – 13 vol%), high temperatures (~ 250ºC), and in the presence of many other gas species. These conditions will be simulated in the student designed reactor. The...

  16. CO2 Capture with Enzyme Synthetic Analogue

    SciTech Connect

    Cordatos, Harry

    2010-03-01

    Project overview provides background on carbonic anhydrase transport mechanism for CO2 in the human body and proposed approach for ARPA-E project to create a synthetic enzyme analogue and utilize it in a membrane for CO2 capture from flue gas.

  17. Aqueous ethylenediamine for CO(2) capture.

    PubMed

    Zhou, Shan; Chen, Xi; Nguyen, Thu; Voice, Alexander K; Rochelle, Gary T

    2010-08-23

    Aqueous ethylenediamine (EDA) has been investigated as a solvent for CO(2) capture from flue gas. EDA can be used at 12 M (mol kg(-1) H(2)O) with an acceptable viscosity of 16 cP (1 cP=10(-3) Pa s) with 0.48 mol CO(2) per equivalent of EDA. Similar to monoethanolamine (MEA), EDA can be used up to 120 degrees C in a stripper without significant thermal degradation. Inhibitor A will effectively eliminate oxidative degradation. Above 120 degrees C, loaded EDA degrades with the production of its cyclic urea and other related compounds. Unlike piperazine, when exposed to oxidative degradation, EDA does not result in excessive foaming. Over much of the loading range, the CO(2) absorption rate with 12 M EDA is comparable to 7 M MEA. However, at typical rich loading, 12 M EDA absorbs CO(2) 2 times slower than 7 M MEA. The capacity of 12 M EDA is 0.72 mol CO(2)/(kg H(2)O+EDA) (for P(CO(2) )=0.5 to 5 kPa at 40 degrees C), which is about double that of MEA. The apparent heat of CO(2) desorption in EDA solution is 84 kJ mol(-1) CO(2); greater than most other amine systems. PMID:20677204

  18. Polymer nanosieve membranes for CO2-capture applications

    NASA Astrophysics Data System (ADS)

    Du, Naiying; Park, Ho Bum; Robertson, Gilles P.; Dal-Cin, Mauro M.; Visser, Tymen; Scoles, Ludmila; Guiver, Michael D.

    2011-05-01

    Microporous organic polymers (MOPs) are of potential significance for gas storage, gas separation and low-dielectric applications. Among many approaches for obtaining such materials, solution-processable MOPs derived from rigid and contorted macromolecular structures are promising because of their excellent mass transport and mass exchange capability. Here we show a class of amorphous MOP, prepared by [2+3] cycloaddition modification of a polymer containing an aromatic nitrile group with an azide compound, showing super-permeable characteristics and outstanding CO2 separation performance, even under polymer plasticization conditions such as CO2/light gas mixtures. This unprecedented result arises from the introduction of tetrazole groups into highly microporous polymeric frameworks, leading to more favourable CO2 sorption with superior affinity in gas mixtures, and selective CO2 transport by presorbed CO2 molecules that limit access by other light gas molecules. This strategy provides a direction in the design of MOP membrane materials for economic CO2 capture processes.

  19. CO2 Capture with Liquid-to-Solid Absorbents: CO2 Capture Process Using Phase-Changing Absorbents

    SciTech Connect

    2010-10-01

    IMPACCT Project: GE and the University of Pittsburgh are developing a unique CO2 capture process in which a liquid absorbent, upon contact with CO2, changes into a solid phase. Once in solid form, the material can be separated and the CO2 can be released for storage by heating. Upon heating, the absorbent returns to its liquid form, where it can be reused to capture more CO2. The approach is more efficient than other solventbased processes because it avoids the heating of extraneous solvents such as water. This ultimately leads to a lower cost of CO2 capture and will lower the additional cost to produce electricity for coal-fired power plants that retrofit their facilities to include this technology.

  20. Combustion-Assisted CO2 Capture Using MECC Membranes

    SciTech Connect

    Sherman, Steven R; Gray, Dr. Joshua R.; Brinkman, Dr. Kyle S.; Huang, Dr. Kevin

    2012-01-01

    Mixed Electron and Carbonate ion Conductor (MECC) membranes have been proposed as a means to separate CO2 from power plant flue gas. Here a modified MECC CO2 capture process is analyzed that supplements retentate pressurization and permeate evacuation as a means to create a CO2 driving force with a process assisted by the catalytic combustion of syngas on the permeate side of the membrane. The combustion reactions consume transported oxygen, making it unavailable for the backwards transport reaction. With this change, the MECC capture system becomes exothermic, and steam for electricity production may be generated from the waste heat. Greater than 90% of the CO2 in the flue gas may be captured, and a compressed CO2 product stream is produced. A fossil-fueled power plant using this process would consume 14% more fuel per unit electricity produced than a power plant with no CO2 capture system, and has the potential to meet U.S. DOE s goal that deployment of a CO2 capture system at a fossil-fueled power plant should not increase the cost of electricity from the combined facility by more than 30%.

  1. Carbon Dioxide Capture: Covalent Organic Frameworks for CO2 Capture (Adv. Mater. 15/2016).

    PubMed

    Zeng, Yongfei; Zou, Ruqiang; Zhao, Yanli

    2016-04-01

    Covalent organic frameworks (COFs) serve as ideal platforms that can selectively adsorb and separate CO2 from gas mixtures. On page 2855, R. Zou, Y. Zhao, and Y. Zeng highlight research progress in this area, compare recent achievements, and present fundamental principles. Different strategies to improve the CO2 capture capability of COFs are elaborated and the capture performance of representative COFs is analyzed. PMID:27075837

  2. CO2 capture and separation from N2/CH4 mixtures by Co@B8/Co@B8(-) and M@B9/M@B9(-) (M = Ir, Rh, Ru) clusters: a theoretical study.

    PubMed

    Wang, Weihua; Zhang, Xiaoxiao; Li, Ping; Sun, Qiao; Li, Zhen; Ren, Cong; Guo, Chao

    2015-01-29

    The discovery of advanced materials with high selectivity and efficiency is essential to realize practical carbon capture and sequestration. Here, we have investigated the interactions of the Co@B8/Co@B8(-) and M@B9/M@B9(-) (M = Ir, Rh, Ru) clusters with CO2, N2, and CH4 gas molecules theoretically. We found that neutral boron clusters have weak interaction with CO2, N2, and CH4 molecules. Similarly, the clusters with their negative charge states have also weak interaction with N2 and CH4 molecules. However, anionic clusters have a strong interaction with CO2, which can be explained by the Lewis acid-base interaction as CO2 (Lewis acid) can gain electron easily from the electron-rich anionic clusters. Moreover, the kinetic stability of the formed complexes after CO2 capture has been validated by ab initio molecular dynamics. In all, the present study demonstrates, for the first time, that the anionic boron wheel ring clusters can be used as potential advanced materials for CO2 capture and separation from flue gas and natural gas mixtures. PMID:25594368

  3. Enzyme-based CO2 capture for advanced life support

    NASA Technical Reports Server (NTRS)

    Ge, Jijun; Cowan, Robert M.; Tu, Chingkuang; McGregor, Martin L.; Trachtenberg, Michael C.

    2002-01-01

    Elevated CO2 levels in air can lead to impaired functioning and even death to humans. Control of CO2 is critical in confined spaces that have little physical or biological buffering capacity (e.g., spacecraft, submarines, or aircraft). A novel enzyme-based contained liquid membrane bioreactor was designed for CO2 capture and certain application cases are reported in this article. The results show that the liquid layer accounts for the major transport resistance. With addition of carbonic anhydrase, the transport resistance decreased by 71%. Volatile organic compounds of the type and concentration expected to be present in either the crew cabin or a plant growth chamber did not influence carbonic anhydrase activity or reactor operation during 1-day operation. Alternative sweep method studies, examined as a means of eliminating consumables, showed that the feed gas could be used successfully in a bypass mode when combined with medium vacuum pressure (-85 kPa) to achieve CO2 separation comparable to that with an inert sweep gas. The reactor exhibited a selectivity for CO2 versus N2 of 1400:1 and CO2 versus O2 is 866:1. The CO2 permeance was 1.44 x 10(-7) mol m-2 Pa-1 s-1 (4.3 x 10(-4) cm3 cm-2 s-1 cmHg-1) at a feed concentration of 0.1% CO2. These data show that the enzyme-based contained liquid membrane is a promising candidate technology that may be suitable for NASA applications to control CO2 in the crew or plant chambers.

  4. Fingerprinting captured CO2 using natural tracers: Determining CO2 fate and proving ownership

    NASA Astrophysics Data System (ADS)

    Flude, Stephanie; Gilfillan, Stuart; Johnston, Gareth; Stuart, Finlay; Haszeldine, Stuart

    2016-04-01

    In the long term, captured CO2 will most likely be stored in large saline formations and it is highly likely that CO2 from multiple operators will be injected into a single saline formation. Understanding CO2 behavior within the reservoir is vital for making operational decisions and often uses geochemical techniques. Furthermore, in the event of a CO2 leak, being able to identify the owner of the CO2 is of vital importance in terms of liability and remediation. Addition of geochemical tracers to the CO2 stream is an effective way of tagging the CO2 from different power stations, but may become prohibitively expensive at large scale storage sites. Here we present results from a project assessing whether the natural isotopic composition (C, O and noble gas isotopes) of captured CO2 is sufficient to distinguish CO2 captured using different technologies and from different fuel sources, from likely baseline conditions. Results include analytical measurements of CO2 captured from a number of different CO2 capture plants and a comprehensive literature review of the known and hypothetical isotopic compositions of captured CO2 and baseline conditions. Key findings from the literature review suggest that the carbon isotope composition will be most strongly controlled by that of the feedstock, but significant fractionation is possible during the capture process; oxygen isotopes are likely to be controlled by the isotopic composition of any water used in either the industrial process or the capture technology; and noble gases concentrations will likely be controlled by the capture technique employed. Preliminary analytical results are in agreement with these predictions. Comparison with summaries of likely storage reservoir baseline and shallow or surface leakage reservoir baseline data suggests that C-isotopes are likely to be valuable tracers of CO2 in the storage reservoir, while noble gases may be particularly valuable as tracers of potential leakage.

  5. CO2 Capture with Enzyme Synthetic Analogue

    SciTech Connect

    Cordatos, Harry

    2010-11-08

    Overview of an ongoing, 2 year research project partially funded by APRA-E to create a novel, synthetic analogue of carbonic anhydrase and incorporate it into a membrane for removal of CO2 from flue gas in coal power plants. Mechanism background, preliminary feasibility study results, molecular modeling of analogue-CO2 interaction, and program timeline are provided.

  6. Supersonic Technology for CO2 Capture: A High Efficiency Inertial CO2 Extraction System

    SciTech Connect

    2010-07-01

    IMPACCT Project: Researchers at ATK and ACENT Laboratories are developing a device that relies on aerospace wind-tunnel technologies to turn CO2 into a condensed solid for collection and capture. ATK’s design incorporates a special nozzle that converges and diverges to expand flue gas, thereby cooling it off and turning the CO2 into solid particles which are removed from the system by a cyclonic separator. This technology is mechanically simple, contains no moving parts and generates no chemical waste, making it inexpensive to construct and operate, readily scalable, and easily integrated into existing facilities. The increase in the cost to coal-fired power plants associated with introduction of this system would be 50% less than current technologies.

  7. Economic and energetic analysis of capturing CO2 from ambient air.

    PubMed

    House, Kurt Zenz; Baclig, Antonio C; Ranjan, Manya; van Nierop, Ernst A; Wilcox, Jennifer; Herzog, Howard J

    2011-12-20

    Capturing carbon dioxide from the atmosphere ("air capture") in an industrial process has been proposed as an option for stabilizing global CO(2) concentrations. Published analyses suggest these air capture systems may cost a few hundred dollars per tonne of CO(2), making it cost competitive with mainstream CO(2) mitigation options like renewable energy, nuclear power, and carbon dioxide capture and storage from large CO(2) emitting point sources. We investigate the thermodynamic efficiencies of commercial separation systems as well as trace gas removal systems to better understand and constrain the energy requirements and costs of these air capture systems. Our empirical analyses of operating commercial processes suggest that the energetic and financial costs of capturing CO(2) from the air are likely to have been underestimated. Specifically, our analysis of existing gas separation systems suggests that, unless air capture significantly outperforms these systems, it is likely to require more than 400 kJ of work per mole of CO(2), requiring it to be powered by CO(2)-neutral power sources in order to be CO(2) negative. We estimate that total system costs of an air capture system will be on the order of $1,000 per tonne of CO(2), based on experience with as-built large-scale trace gas removal systems. PMID:22143760

  8. Porous Hexacyanometalates for CO2 capture applications

    SciTech Connect

    Motkuri, Radha K.; Thallapally, Praveen K.; McGrail, B. Peter

    2013-07-30

    Prussian blue analogues of M3[Fe(CN)6]2 x H2O (where M=Fe, Mn and Ni) were synthesized, characterized and tested for their gas sorption capabilities. The sorption studies reveal that, these Prussian blue materials preferentially sorb CO2 over N2 and CH4 at low pressure (1bar).

  9. Economic and energetic analysis of capturing CO2 from ambient air

    PubMed Central

    House, Kurt Zenz; Baclig, Antonio C.; Ranjan, Manya; van Nierop, Ernst A.; Wilcox, Jennifer; Herzog, Howard J.

    2011-01-01

    Capturing carbon dioxide from the atmosphere (“air capture”) in an industrial process has been proposed as an option for stabilizing global CO2 concentrations. Published analyses suggest these air capture systems may cost a few hundred dollars per tonne of CO2, making it cost competitive with mainstream CO2 mitigation options like renewable energy, nuclear power, and carbon dioxide capture and storage from large CO2 emitting point sources. We investigate the thermodynamic efficiencies of commercial separation systems as well as trace gas removal systems to better understand and constrain the energy requirements and costs of these air capture systems. Our empirical analyses of operating commercial processes suggest that the energetic and financial costs of capturing CO2 from the air are likely to have been underestimated. Specifically, our analysis of existing gas separation systems suggests that, unless air capture significantly outperforms these systems, it is likely to require more than 400 kJ of work per mole of CO2, requiring it to be powered by CO2-neutral power sources in order to be CO2 negative. We estimate that total system costs of an air capture system will be on the order of $1,000 per tonne of CO2, based on experience with as-built large-scale trace gas removal systems. PMID:22143760

  10. Amine-based CO2 capture technology development from the beginning of 2013-a review.

    PubMed

    Dutcher, Bryce; Fan, Maohong; Russell, Armistead G

    2015-02-01

    It is generally accepted by the scientific community that anthropogenic CO2 emissions are leading to global climate change, notably an increase in global temperatures commonly referred to as global warming. The primary source of anthropogenic CO2 emissions is the combustion of fossil fuels for energy. As society's demand for energy increases and more CO2 is produced, it becomes imperative to decrease the amount emitted to the atmosphere. One promising approach to do this is to capture CO2 at the effluent of the combustion site, namely, power plants, in a process called postcombustion CO2 capture. Technologies to achieve this are heavily researched due in large part to the intuitive nature of removing CO2 from the stack gas and the ease in retrofitting existing CO2 sources with these technologies. As such, several reviews have been written on postcombustion CO2 capture. However, it is a fast-developing field, and the most recent review papers already do not include the state-of-the-art research. Notable among CO2 capture technologies are amine-based technologies. Amines are well-known for their reversible reactions with CO2, which make them ideal for the separation of CO2 from many CO2-containing gases, including flue gas. For this reason, this review will cover amine-based technology developed and published in and after the year 2013. PMID:25607244

  11. Conductive Graphitic Carbon Nitride as an Ideal Material for Electrocatalytically Switchable CO2 Capture

    NASA Astrophysics Data System (ADS)

    Tan, Xin; Kou, Liangzhi; Tahini, Hassan A.; Smith, Sean C.

    2015-12-01

    Good electrical conductivity and high electron mobility of the sorbent materials are prerequisite for electrocatalytically switchable CO2 capture. However, no conductive and easily synthetic sorbent materials are available until now. Here, we examined the possibility of conductive graphitic carbon nitride (g-C4N3) nanosheets as sorbent materials for electrocatalytically switchable CO2 capture. Using first-principle calculations, we found that the adsorption energy of CO2 molecules on g-C4N3 nanosheets can be dramatically enhanced by injecting extra electrons into the adsorbent. At saturation CO2 capture coverage, the negatively charged g-C4N3 nanosheets achieve CO2 capture capacities up to 73.9 × 1013 cm-2 or 42.3 wt%. In contrast to other CO2 capture approaches, the process of CO2 capture/release occurs spontaneously without any energy barriers once extra electrons are introduced or removed, and these processes can be simply controlled and reversed by switching on/off the charging voltage. In addition, these negatively charged g-C4N3 nanosheets are highly selective for separating CO2 from mixtures with CH4, H2 and/or N2. These predictions may prove to be instrumental in searching for a new class of experimentally feasible high-capacity CO2 capture materials with ideal thermodynamics and reversibility.

  12. Conductive Graphitic Carbon Nitride as an Ideal Material for Electrocatalytically Switchable CO2 Capture

    PubMed Central

    Tan, Xin; Kou, Liangzhi; Tahini, Hassan A.; Smith, Sean C.

    2015-01-01

    Good electrical conductivity and high electron mobility of the sorbent materials are prerequisite for electrocatalytically switchable CO2 capture. However, no conductive and easily synthetic sorbent materials are available until now. Here, we examined the possibility of conductive graphitic carbon nitride (g-C4N3) nanosheets as sorbent materials for electrocatalytically switchable CO2 capture. Using first-principle calculations, we found that the adsorption energy of CO2 molecules on g-C4N3 nanosheets can be dramatically enhanced by injecting extra electrons into the adsorbent. At saturation CO2 capture coverage, the negatively charged g-C4N3 nanosheets achieve CO2 capture capacities up to 73.9 × 1013 cm−2 or 42.3 wt%. In contrast to other CO2 capture approaches, the process of CO2 capture/release occurs spontaneously without any energy barriers once extra electrons are introduced or removed, and these processes can be simply controlled and reversed by switching on/off the charging voltage. In addition, these negatively charged g-C4N3 nanosheets are highly selective for separating CO2 from mixtures with CH4, H2 and/or N2. These predictions may prove to be instrumental in searching for a new class of experimentally feasible high-capacity CO2 capture materials with ideal thermodynamics and reversibility. PMID:26621618

  13. CO2-Binding-Organic-Liquids-Enhanced CO2 Capture using Polarity-Swing-Assisted Regeneration

    SciTech Connect

    Zhang, Jian; Kutnyakov, Igor; Koech, Phillip K.; Zwoster, Andy; Howard, Chris; Zheng, Feng; Freeman, Charles J.; Heldebrant, David J.

    2013-01-01

    A new solvent-based CO2 capture process couples the unique attributes of non-aqueous, CO2-binding organic liquids (CO2BOLs) with the newly discovered polarity-swing-assisted regeneration (PSAR) process that is unique to switchable ionic liquids. Laboratory measurements with PSAR indicate the ability to achieve a regeneration effect at 75°C comparable to that at 120°C using thermal regeneration only. Initial measurements also indicate that the kinetic behavior of CO2 release is also improved with PSAR. Abstract cleared PNWD-SA-9743

  14. Simteche Hydrate CO2 Capture Process

    SciTech Connect

    Nexant and Los Alamos National Laboratory

    2006-09-30

    As a result of an August 4, 2005 project review meeting held at Los Alamos National Laboratory (LANL) to assess the project's technical progress, Nexant/Simteche/LANL project team was asked to meet four targets related to the existing project efforts. The four targets were to be accomplished by the September 30, 2006. These four targets were: (1) The CO{sub 2} hydrate process needs to show, through engineering and sensitivity analysis, that it can achieve 90% CO{sub 2} capture from the treated syngas stream, operating at 1000 psia. The cost should indicate the potential of achieving the Sequestration Program's cost target of less than 10% increase in the cost of electricity (COE) of the non-CO{sub 2} removal IGCC plant or demonstrate a significant cost reduction from the Selexol process cost developed in the Phase II engineering analysis. (2) The ability to meet the 20% cost share requirement for research level efforts. (3) LANL identifies through equilibrium and bench scale testing a once-through 90% CO{sub 2} capture promoter that supports the potential to achieve the Sequestration Program's cost target. Nexant is to perform an engineering analysis case to verify any economic benefits, as needed; no ETM validation is required, however, for this promoter for FY06. (4) The CO{sub 2} hydrate once-through process is to be validated at 1000 psia with the ETM at a CO{sub 2} capture rate of 60% without H{sub 2}S. The performance of 68% rate of capture is based on a batch, equilibrium data with H{sub 2}S. Validation of the test results is required through multiple runs and engineering calculations. Operational issues will be solved that will specifically effect the validation of the technology. Nexant was given the primary responsibility for Target No.1, while Simteche was mainly responsible for Target No.2; with LANL having the responsibility of Targets No.3 and No.4.

  15. Polyurethane Foam-Based Ultramicroporous Carbons for CO2 Capture.

    PubMed

    Ge, Chao; Song, Jian; Qin, Zhangfeng; Wang, Jianguo; Fan, Weibin

    2016-07-27

    A series of sustainable porous carbon materials were prepared from waste polyurethane foam and investigated for capture of CO2. The effects of preparation conditions, such as precarbonization, KOH to carbon precursor weight ratio, and activation temperature, on the porous structure and CO2 adsorption properties were studied for the purpose of controlling pore sizes and nitrogen content and developing high-performance materials for capture of CO2. The sample prepared at optimum conditions shows CO2 adsorption capacities of 6.67 and 4.33 mmol·g(-1) at 0 and 25 °C under 1 bar, respectively, which are comparable to those of the best reported porous carbons prepared from waste materials. The HCl treatment experiment reveals that about 80% of CO2 adsorption capacity arises from physical adsorption, while the other 20% is due to the chemical adsorption originated from the interaction of basic N groups and CO2 molecules. The relationship between CO2 uptake and pore size at different temperatures indicates that the micropores with pore size smaller than 0.86 and 0.70 nm play a dominant role in the CO2 adsorption at 0 and 25 °C, respectively. It was found that the obtained carbon materials exhibited high recyclability and high selectivity to adsorption of CO2 from the CO2 and N2 mixture. PMID:27376177

  16. Development of Novel CO2 Adsorbents for Capture of CO2 from Flue Gas

    SciTech Connect

    Fauth, D.J.; Filburn, T.P.; Gray, M.L.; Hedges, S.W.; Hoffman, J.; Pennline, H.W.; Filburn, T.

    2007-06-01

    Capturing CO2 emissions generated from fossil fuel-based power plants has received widespread attention and is considered a vital course of action for CO2 emission abatement. Efforts are underway at the Department of Energy’s National Energy Technology Laboratory to develop viable energy technologies enabling the CO2 capture from large stationary point sources. Solid, immobilized amine sorbents (IAS) formulated by impregnation of liquid amines within porous substrates are reactive towards CO2 and offer an alternative means for cyclic capture of CO2 eliminating, to some degree, inadequacies related to chemical absorption by aqueous alkanolamine solutions. This paper describes synthesis, characterization, and CO2 adsorption properties for IAS materials previously tested to bind and release CO2 and water vapor in a closed loop life support system. Tetraethylenepentamine (TEPA), acrylonitrile-modified tetraethylenepentamine (TEPAN), and a single formulation consisting of TEPAN and N, N’-bis(2-hydroxyethyl)ethylenediamine (BED) were individually supported on a poly (methyl methacrylate) (PMMA) substrate and examined. CO2 adsorption profiles leading to reversible CO2 adsorption capacities were obtained using thermogravimetry. Under 10% CO2 in nitrogen at 25°C and 1 atm, TEPA supported on PMMA over 60 minutes adsorbed ~3.2 mmol/g{sorbent} whereas, TEPAN supported on PMMA along with TEPAN and BED supported on PMMA adsorbed ~1.7 mmol/g{sorbent} and ~2.3 mmol/g{sorbent} respectively. Cyclic experiments with a 1:1 weight ratio of TEPAN and BED supported on poly (methyl methacrylate) beads utilizing a fixed-bed flow system with 9% CO2, 3.5% O2, nitrogen balance with trace gas constituents were studied. CO2 adsorption capacity was ~ 3 mmols CO2/g{sorbent} at 40°C and 1.4 atm. No beneficial effect on IAS performance was found using a moisture-laden flue gas mixture. Tests with 750 ppmv NO in a humidified gas stream revealed negligible NO sorption onto the IAS. A high SO2

  17. CO(2) capture from dilute gases as a component of modern global carbon management.

    PubMed

    Jones, Christopher W

    2011-01-01

    The growing atmospheric CO(2) concentration and its impact on climate have motivated widespread research and development aimed at slowing or stemming anthropogenic carbon emissions. Technologies for carbon capture and sequestration (CCS) employing mass separating agents that extract and purify CO(2) from flue gas emanating from large point sources such as fossil fuel-fired electricity-generating power plants are under development. Recent advances in solvents, adsorbents, and membranes for postcombust- ion CO(2) capture are described here. Specifically, room-temperature ionic liquids, supported amine materials, mixed matrix and facilitated transport membranes, and metal-organic framework materials are highlighted. In addition, the concept of extracting CO(2) directly from ambient air (air capture) as a means of reducing the global atmospheric CO(2) concentration is reviewed. For both conventional CCS from large point sources and air capture, critical research needs are identified and discussed. PMID:22432609

  18. Halloysite Nanotubes Capturing Isotope Selective Atmospheric CO2

    PubMed Central

    Jana, Subhra; Das, Sankar; Ghosh, Chiranjit; Maity, Abhijit; Pradhan, Manik

    2015-01-01

    With the aim to capture and subsequent selective trapping of CO2, a nanocomposite has been developed through selective modification of the outer surface of the halloysite nanotubes (HNTs) with an organosilane to make the nanocomposite a novel solid-phase adsorbent to adsorb CO2 from the atmosphere at standard ambient temperature and pressure. The preferential adsorption of three major abundant isotopes of CO2 (12C16O2, 13C16O2, and 12C16O18O) from the ambient air by amine functionalized HNTs has been explored using an optical cavity-enhanced integrated cavity output spectroscopy. CO2 adsorption/desorption cycling measurements demonstrate that the adsorbent can be regenerated at relatively low temperature and thus, recycled repeatedly to capture atmospheric CO2. The amine grafted halloysite shows excellent stability even in oxidative environments and has high efficacy of CO2 capture, introducing a new route to the adsorption of isotope selective atmospheric CO2. PMID:25736700

  19. CO2 capture using zeolite 13X prepared from bentonite

    NASA Astrophysics Data System (ADS)

    Chen, Chao; Park, Dong-Wha; Ahn, Wha-Seung

    2014-02-01

    Zeolite 13X was prepared using bentonite as the raw material by alkaline fusion followed by a hydrothermal treatment without adding any extra silica or alumina sources. The prepared zeolite 13X was characterized by X-ray powder diffraction, N2-adsorption-desorption measurements, and scanning electron microscopy. The CO2 capture performance of the prepared zeolite 13X was examined under both static and flow conditions. The prepared zeolite 13X showed a high BET surface area of 688 m2/g with a high micropore volume (0.30 cm3/g), and exhibited high CO2 capture capacity (211 mg/g) and selectivity to N2 (CO2/N2 = 37) at 25 °C and 1 bar. In addition, the material showed fast adsorption kinetics, and stable CO2 adsorption-desorption recycling performance at both 25 and 200 °C.

  20. CO2 mitigation via capture and chemical conversion in seawater.

    PubMed

    Rau, Greg H

    2011-02-01

    A lab-scale seawater/mineral carbonate gas scrubber was found to remove up to 97% of CO(2) in a simulated flue gas stream at ambient temperature and pressure, with a large fraction of this carbon ultimately converted to dissolved calcium bicarbonate. After full equilibration with air, up to 85% of the captured carbon was retained in solution, that is, it did not degas or precipitate. Thus, above-ground CO(2) hydration and mineral carbonate scrubbing may provide a relatively simple point-source CO(2) capture and storage scheme at coastal locations. Such low-tech CO(2) mitigation could be especially relevant for retrofitting to existing power plants and for deployment in the developing world, the primary source of future CO(2) emissions. Addition of the resulting alkaline solution to the ocean may benefit marine ecosystems that are currently threatened by acidification, while also allowing the utilization of the vast potential of the sea to safely sequester anthropogenic carbon. This approach in essence hastens Nature's own very effective but slow CO(2) mitigation process; carbonate mineral weathering is a major consumer of excess atmospheric CO(2) and ocean acidity on geologic times scales. PMID:21189009

  1. Industrial CO2 Removal: CO2 Capture from Ambient Air and Geological Sequestration

    SciTech Connect

    Dooley, James J.

    2011-06-08

    This abstract and its accompanying presentation will provide an overview of two distinct industrial processes for removing carbon dioxide (CO2) from the atmosphere as a means of addressing anthropogenic climate change. The first of these is carbon dioxide capture and storage (CCS) coupled with large scale biomass production (hereafter referred to as bioCCS). The second is CO2 capture from ambient air via industrial systems (hereafter referred to as direct air capture (DAC)). In both systems, the captured CO2 would be injected into deep geologic formations so as to isolate it from the atmosphere. The technical literature is clear that both of these technologies are technically feasible as of today (IPCC, 2005; Keith, 2009; Lackner, 2009; Luckow et al., 2010; Ranjan and Herzog, 2011). What is uncertain is the relative cost of these industrial ambient-air CO2 removal systems when compared to other emissions mitigation measures, the ultimate timing and scale of their deployment, and the resolution of potential site specific constraints that would impact their ultimate commercial deployment.

  2. Direct Air Capture of CO2 by Physisorbent Materials.

    PubMed

    Kumar, Amrit; Madden, David G; Lusi, Matteo; Chen, Kai-Jie; Daniels, Emma A; Curtin, Teresa; Perry, John J; Zaworotko, Michael J

    2015-11-23

    Sequestration of CO2, either from gas mixtures or directly from air (direct air capture, DAC), could mitigate carbon emissions. Here five materials are investigated for their ability to adsorb CO2 directly from air and other gas mixtures. The sorbents studied are benchmark materials that encompass four types of porous material, one chemisorbent, TEPA-SBA-15 (amine-modified mesoporous silica) and four physisorbents: Zeolite 13X (inorganic); HKUST-1 and Mg-MOF-74/Mg-dobdc (metal-organic frameworks, MOFs); SIFSIX-3-Ni, (hybrid ultramicroporous material). Temperature-programmed desorption (TPD) experiments afforded information about the contents of each sorbent under equilibrium conditions and their ease of recycling. Accelerated stability tests addressed projected shelf-life of the five sorbents. The four physisorbents were found to be capable of carbon capture from CO2-rich gas mixtures, but competition and reaction with atmospheric moisture significantly reduced their DAC performance. PMID:26440308

  3. Charge-controlled switchable CO2 capture on boron nitride nanomaterials.

    PubMed

    Sun, Qiao; Li, Zhen; Searles, Debra J; Chen, Ying; Lu, Gaoqing Max; Du, Aijun

    2013-06-01

    Increasing concerns about the atmospheric CO2 concentration and its impact on the environment are motivating researchers to discover new materials and technologies for efficient CO2 capture and conversion. Here, we report a study of the adsorption of CO2, CH4, and H2 on boron nitride (BN) nanosheets and nanotubes (NTs) with different charge states. The results show that the process of CO2 capture/release can be simply controlled by switching on/off the charges carried by BN nanomaterials. CO2 molecules form weak interactions with uncharged BN nanomaterials and are weakly adsorbed. When extra electrons are introduced to these nanomaterials (i.e., when they are negatively charged), CO2 molecules become tightly bound and strongly adsorbed. Once the electrons are removed, CO2 molecules spontaneously desorb from BN absorbents. In addition, these negatively charged BN nanosorbents show high selectivity for separating CO2 from its mixtures with CH4 and/or H2. Our study demonstrates that BN nanomaterials are excellent absorbents for controllable, highly selective, and reversible capture and release of CO2. In addition, the charge density applied in this study is of the order of 10(13) cm(-2) of BN nanomaterials and can be easily realized experimentally. PMID:23678978

  4. Separation of CO2 from flue gas using electrochemical cells

    SciTech Connect

    Pennline HW, Granite EJ, Luebke DR,

    2010-06-01

    Past research with high temperature molten carbonate electrochemical cells has shown that carbon dioxide can be separated from flue gas streams produced by pulverized coal combustion for power generation. However, the presence of trace contaminants, i.e., sulfur dioxide and nitric oxides, will impact the electrolyte within the cell. If a lower temperature cell could be devised that would utilize the benefits of commercially-available, upstream desulfurization and denitrification in the power plant, then this CO2 separation technique can approach more viability in the carbon sequestration area. Recent work has led to the assembly and successful operation of a low temperature electrochemical cell. In the proof-of-concept testing with this cell, an anion exchange membrane was sandwiched between gas-diffusion electrodes consisting of nickel-based anode electrocatalysts on carbon paper. When a potential was applied across the cell and a mixture of oxygen and carbon dioxide was flowed over the wetted electrolyte on the cathode side, a stream of CO2 to O2 was produced on the anode side, suggesting that carbonate/ bicarbonate ions are the CO2 carrier in the membrane. Since a mixture of CO2 and O2 is produced, the possibility exists to use this stream in oxy-firing of additional fuel. From this research, a novel concept for efficiently producing a carbon dioxide rich effluent from combustion of a fossil fuel was proposed. Carbon dioxide and oxygen are captured from the flue gas of a fossilfuel combustor by one or more electrochemical cells or cell stacks. The separated stream is then transferred to an oxy-fired combustor which uses the gas stream for ancillary combustion, ultimately resulting in an effluent rich in carbon dioxide. A portion of the resulting flow produced by the oxy-fired combustor may be continuously recycled back into the oxy-fired combustor for temperature control and an optimal carbon dioxide rich effluent

  5. Separation of CO2 from flue gas using electrochemical cells

    SciTech Connect

    Pennline, H.W; Granite, E.J.; Luebke, D.R; Kitchin, J.R; Landon, J.; Weiland, L.M.

    2010-06-01

    ABSTRACT Past research with high temperature molten carbonate electrochemical cells has shown that carbon dioxide can be separated from flue gas streams produced by pulverized coal combustion for power generation, However, the presence of trace contaminants, i.e" sulfur dioxide and nitric oxides, will impact the electrolyte within the cell. If a lower temperature cell could be devised that would utilize the benefits of commercially-available, upstream desulfurization and denitrification in the power plant, then this CO2 separation technique can approach more viability in the carbon sequestration area, Recent work has led to the assembly and successful operation of a low temperature electrochemical cell. In the proof-of-concept testing with this cell, an anion exchange membrane was sandwiched between gas-diffusion electrodes consisting of nickel-based anode electrocatalysts on carbon paper. When a potential was applied across the cell and a mixture of oxygen and carbon dioxide was flowed over the wetted electrolyte on the cathode side, a stream of CO2 to O2 was produced on the anode side, suggesting that carbonate/ bicarbonate ions are the CO2 carrier in the membrane. Since a mixture of CO 2 and 02 is produced, the possibility exists to use this stream in oxy-firing of additional fuel. From this research, a novel concept for efficiently producing a carbon dioxide rich effiuent from combustion of a fossil fuel was proposed. Carbon dioxide and oxygen are captured from the flue gas of a fossilfuel combustor by one or more electrochemical cells or cell stacks. The separated stream is then transferred to an oxy-fired combustor which uses the gas stream for ancillary combustion, ultimately resulting in an effluent rich in carbon dioxide, A portion of the resulting flow produced by the oxy-fired combustor may be continuously recycled back into the oxy-fired combustor for temperature control and an optimal carbon dioxide rich effluent.

  6. Choosing amine-based absorbents for CO2 capture.

    PubMed

    Gomes, João; Santos, Samuel; Bordado, João

    2015-01-01

    CO2 capture from gaseous effluents is one of the great challenges faced by chemical and environmental engineers, as the increase in CO2 levels in the Earth atmosphere might be responsible for dramatic climate changes. From the existing capture technologies, the only proven and mature technology is chemical absorption using aqueous amine solutions. However, bearing in mind that this process is somewhat expensive, it is important to choose the most efficient and, at the same time, the least expensive solvents. For this purpose, a pilot test facility was assembled and includes an absorption column, as well as a stripping column, a heat exchanger between the two columns, a reboiler for the stripping column, pumping systems, surge tanks and all necessary instrumentation and control systems. Some different aquous amine solutions were tested on this facility and it was found that, from a set of six tested amines, diethanol amine is the one that turned out to be the most economical choice, as it showed a higher CO2 loading capacity (0.982 mol of CO2 per mol of amine) and the lowest price per litre (25.70 €/L), even when compared with monoethanolamine, the benchmark solvent, exhibiting a price per litre of 30.50 €/L. PMID:25409579

  7. A NOVEL CO2 SEPARATION SYSTEM

    SciTech Connect

    Robert J. Copeland; Gokhan Alptekin; Mike Cesario; Steven Gebhard; Yevgenia Gershanovich

    1999-01-01

    Because of concern over global climate change, new systems are needed that produce electricity from fossil fuels and emit less CO{sub 2}. The fundamental problem with current CO{sub 2} separation systems is the need to separate dilute CO{sub 2} and pressurize it for storage or sequestration. This is an energy intensive process that can reduce plant efficiency by 9-37% and double the cost of electricity.

  8. Amine-pillared Nanosheet Adsorbents for CO2 Capture Applications

    NASA Astrophysics Data System (ADS)

    Jiang, Hui

    Amine-functionalized solid adsorbents have gained attention within the last decade for their application in carbon dioxide capture, due to their many advantages such as low energy cost for regeneration, tunable structure, elimination of corrosion problems, and additional advantages. However, one of the challenges facing this technology is to accomplish both high CO 2 capture capacity along with high CO2 diffusion rates concurrently. Current amine-based solid sorbents such as porous materials similar to SBA-15 have large pores diffusion entering molecules; however, the pores become clogged upon amine inclusion. To meet this challenge, our group's solution involves the creation of a new type of material which we are calling-amino-pillared nanosheet (APN) adsorbents which are generated from layered nanosheet precursors. These materials are being proposed because of their unique lamellar structure which exhibits ability to be modified by organic or inorganic pillars through consecutive swelling and pillaring steps to form large mesoporous interlayer spaces. After the expansion of the layer space through swelling and pillaring, the large pore space can be functionalized with amine groups. This selective functionalization is possible by the choice of amine group introduced. Our choice, large amine molecules, do not access the micropore within each layer; however, either physically or chemically immobilized onto the surface of the mesoporous interlayer space between each layer. The final goal of the research is to investigate the ability to prepare APN adsorbents from a model nanoporous layered materials including nanosheets precursor material MCM-22(P) and nanoporous layered silicate material AMH-3. MCM-22(P) contains 2-dimensional porous channels, 6 membered rings (MB) openings perpendicular to the layers and 10 MB channels in the plane of the layers. However, the transport limiting openings (6 MB) to the layers is smaller than CO2 gas molecules. In contrast, AMH-3 has

  9. CO2 SEPARATIONS USING ZEOLITE MEMBRANES

    SciTech Connect

    Richard D. Noble; John L. Falconer

    2001-06-30

    Zeolite and other inorganic molecular sieve membranes have shown potential for separations based on molecular size and shape because of their small pore sized, typically less than 1 nm, and their narrow pore size distribution. The high thermal and chemical stability of these inorganic crystals make them ideal materials for use in high temperature applications such as catalytic membrane reactors. Most of the progress with zeolite membranes has been with MFI zeolites prepared on porous disks and tubes. The MFI zeolite is a medium pore size structure having nearly circular pores with diameters between .53 and .56 nm. Separation experiments through MFI membranes indicate that competitive adsorption separates light gas mixtures. Light gas selectivities are typically small, however, owing to small differences in adsorption strengths and their small sizes relative to the MFI pore opening. Furthermore, competitive adsorption does not work well at high temperature where zeolite membranes are stable and have potential application. Separation by differences in size has a greater potential to work at high temperature than competitive adsorption, but pores smaller than those in MFI zeolites are required. Therefore, some studies focused on the synthesis of a small, 8-membered-pore structures such as zeolite A (0.41-nm pore diameter) and SAPO-34, a chabazite (about .4-nm pore diameter with about 1.4 nm cages) analog. The small pore size of the zeolite A and SAPO-34 structures made the separation of smaller molecules by differences in size possible. Zeolite MFI and SAPO-34 membranes were prepared on the inside surface of porous alumina tubes by hydrothermal synthesis, and single gas and binary mixture permeances were measured to characterize the membrane's performance. A mathematical diffusion model was developed to determine the relative quantities of zeolite and non-zeolite pores in different membranes by modeling the permeation date of CO{sub 2}. This model expresses the total

  10. Recent advances in CO2 capture and utilization.

    PubMed

    Yu, Kai Man Kerry; Curcic, Igor; Gabriel, Joseph; Tsang, Shik Chi Edman

    2008-01-01

    Energy and the environment are two of the most important issues this century. More than 80 % of our energy comes from the combustion of fossil fuels, which will still remain the dominant energy source for years to come. It is agreed that carbon dioxide produced from the combustion process to be the most important anthropogenic greenhouse gas leading to global warming. Atmospheric CO(2) concentrations have indeed increased by almost 100 ppm since their pre-industrial level, reaching 384 ppm in 2007 with a total annual emission of over 35 Gt. Prompt global action to resolve the CO(2) crisis is therefore needed. To pursue such an action, we are urged to save energy without the unnecessary production of carbon emissions and to use energy in more efficient ways, but alternative methods to mitigate the greenhouse gas have to be considered. This Minireview highlights some recent promising research activities and their prospects in the areas of carbon capture and storage and chemical fixation of CO(2) in constructing a future low-carbon global economy with reference to energy source, thermodynamic considerations, net carbon emissions and availability of reagents. PMID:18985640

  11. A Novel Theoretical Method to Search Good Candidates of Solid Sorbents for CO2 Capture

    SciTech Connect

    Duan, Yuhua

    2008-07-01

    The increasing atmospheric CO2 concentration is the most important environmental issue of global warming that the world faces today. During past few decades, many technologies have been developing to separate and capture CO2 from coal gasifier. As high temperature CO2 absorbents, solid materials are potential candidates. Lithium silicate(Li4SiO4) and zirconate(Li2ZrO3) have been studying for CO2 capture by researchers at Toshiba and found that they absorb CO2 at 773K and release CO2 around 973K. Based on these well-known experimental exploring results on these lithium salts, we have been developing a novel theoretical methodology to search better solid materials for CO2 capture: (1) Based on the crystal structures of solids, the density functional calculations are performed to obtain their electronic structural properties and their binding energies. The energy change(ΔE) for the reaction solid_sorbent+CO2 ↔ sorbent_CO2+ solid are evaluated. (2) For a vast of data-bank of solid materials, as our first filter if |ΔE|<|ΔGLi2SiO4|, where ΔG is the free energy change for reaction of Li2SiO4+CO2↔ Li2CO3 +Li2SiO3, we select this solid as a potential good candidate for CO2 capture. (3) For these possible candidates, we further perform phonon calculations and obtain their vibration frequencies. With them, partition functions of solids(Z) can be calculated out. With Z, the thermal dynamical properties (zero point energy, entropy, enthalpy, free energy, etc.) under different conditions (temperature(T), pressure(P)) can be readily calculated. With them, the chemical potentials(Δμ)(functional of T and P) for the sorption/desorption reaction are evaluated. (4) Using Δμ as our second filter, we can reduce the number of our selected good candidates to a small number of better candidates. (5) The last step is to make the fine tune (the 3rd filter) the better candidates to a small set of the best candidates by considering the operating conditions(T, P, etc.), absorbing

  12. Synthetic Catalysts for CO2 Storage: Catalytic Improvement of Solvent Capture Systems

    SciTech Connect

    2010-08-15

    IMPACCT Project: LLNL is designing a process to pull CO2 out of the exhaust gas of coal-fired power plants so it can be transported, stored, or utilized elsewhere. Human lungs rely on an enzyme known as carbonic anhydrase to help separate CO2 from our blood and tissue as part of the normal breathing process. LLNL is designing a synthetic catalyst with the same function as this enzyme. The catalyst can be used to quickly capture CO2 from coal exhaust, just as the natural enzyme does in our lungs. LLNL is also developing a method of encapsulating chemical solvents in permeable microspheres that will greatly increase the speed of binding of CO2. The goal of the project is an industry-ready chemical vehicle that can withstand the harsh environments found in exhaust gas and enable new, simple process designs requiring less capital investment.

  13. Capture CO2 from Ambient Air Using Nanoconfined Ion Hydration.

    PubMed

    Shi, Xiaoyang; Xiao, Hang; Lackner, Klaus S; Chen, Xi

    2016-03-14

    Water confined in nanoscopic pores is essential in determining the energetics of many physical and chemical systems. Herein, we report a recently discovered unconventional, reversible chemical reaction driven by water quantities in nanopores. The reduction of the number of water molecules present in the pore space promotes the hydrolysis of CO3(2-) to HCO3(-) and OH(-). This phenomenon led to a nano-structured CO2 sorbent that binds CO2 spontaneously in ambient air when the surrounding is dry, while releasing it when exposed to moisture. The underlying mechanism is elucidated theoretically by computational modeling and verified by experiments. The free energy of CO3 (2-) hydrolysis in nanopores reduces with a decrease of water availability. This promotes the formation of OH(-), which has a high affinity to CO2 . The effect is not limited to carbonate/bicarbonate, but is extendable to a series of ions. Humidity-driven sorption opens a new approach to gas separation technology. PMID:26914978

  14. Capture and Sequestration of CO2 at the Boise White Paper Mill

    SciTech Connect

    B.P. McGrail; C.J. Freeman; G.H. Beeman; E.C. Sullivan; S.K. Wurstner; C.F. Brown; R.D. Garber; D. Tobin E.J. Steffensen; S. Reddy; J.P. Gilmartin

    2010-06-16

    This report documents the efforts taken to develop a preliminary design for the first commercial-scale CO2 capture and sequestration (CCS) project associated with biomass power integrated into a pulp and paper operation. The Boise Wallula paper mill is located near the township of Wallula in Southeastern Washington State. Infrastructure at the paper mill will be upgraded such that current steam needs and a significant portion of the current mill electric power are supplied from a 100% biomass power source. A new biomass power system will be constructed with an integrated amine-based CO2 capture plant to capture approximately 550,000 tons of CO2 per year for geologic sequestration. A customized version of Fluor Corporation’s Econamine Plus™ carbon capture technology will be designed to accommodate the specific chemical composition of exhaust gases from the biomass boiler. Due to the use of biomass for fuel, employing CCS technology represents a unique opportunity to generate a net negative carbon emissions footprint, which on an equivalent emissions reduction basis is 1.8X greater than from equivalent fossil fuel sources (SPATH and MANN, 2004). Furthermore, the proposed project will offset a significant amount of current natural gas use at the mill, equating to an additional 200,000 tons of avoided CO2 emissions. Hence, the total net emissions avoided through this project equates to 1,100,000 tons of CO2 per year. Successful execution of this project will provide a clear path forward for similar kinds of emissions reduction that can be replicated at other energy-intensive industrial facilities where the geology is suitable for sequestration. This project also represents a first opportunity for commercial development of geologic storage of CO2 in deep flood basalt formations. The Boise paper mill site is host to a Phase II pilot study being carried out under DOE’s Regional Carbon Partnership Program. Lessons learned from this pilot study and other separately

  15. CO2 capture using fly ash from coal fired power plant and applications of CO2-captured fly ash as a mineral admixture for concrete.

    PubMed

    Siriruang, Chaichan; Toochinda, Pisanu; Julnipitawong, Parnthep; Tangtermsirikul, Somnuk

    2016-04-01

    The utilization of fly ash as a solid sorbent material for CO2 capture via surface adsorption and carbonation reaction was evaluated as an economically feasible CO2 reduction technique. The results show that fly ash from a coal fired power plant can capture CO2 up to 304.7 μmol/g fly ash, consisting of 2.9 and 301.8 μmol/g fly ash via adsorption and carbonation, respectively. The CO2 adsorption conditions (temperature, pressure, and moisture) can affect CO2 capture performance of fly ash. The carbonation of CO2 with free CaO in fly ashes was evaluated and the results indicated that the reaction consumed most of free CaO in fly ash. The fly ashes after CO2 capture were further used for application as a mineral admixture for concrete. Properties such as water requirement, compressive strength, autoclave expansion, and carbonation depth of mortar and paste specimens using fly ash before and after CO2 capture were tested and compared with material standards. The results show that the expansion of mortar specimens using fly ash after CO2 capture was greatly reduced due to the reduction of free CaO content in the fly ash compared to the expansion of specimens using fresh fly ash. There were no significant differences in the water requirement and compressive strength of specimens using fly ash, before and after CO2 capture process. The results from this study can lead to an alternative CO2 capture technique with doubtless utilization of fly ash after CO2 capture as a mineral admixture for concrete. PMID:26803257

  16. Nitrogen-rich porous adsorbents for CO2 capture and storage.

    PubMed

    Li, Pei-Zhou; Zhao, Yanli

    2013-08-01

    The construction of physical or chemical adsorbents for CO2 capture and sequestration (CCS) is a vital technology in the interim period on the way towards a sustainable low-carbon future. The search for efficient materials to satisfy the increasing demand for CCS has become extremely important. Porous materials, including porous silica, porous carbons, and newly developed metal-organic frameworks and porous organic polymers, possessing regular and well-defined porous geometry and having a high surface area and pore volume, have been widely studied for separations on laboratory scale. On account of the dipole-quadrupole interactions between the polarizable CO2 molecule and the accessible nitrogen site, the investigations have indicated that the incorporation of accessible nitrogen-donor groups into the pore walls of porous materials can improve the affinity to CO2 and increase the CO2 uptake capacity and selectivity. The CO2 -adsorption process based on solid nitrogen-rich porous adsorbents does generally not require heating of a large amount of water (60-70 wt%) for regeneration, while such a heating approach cannot be avoided in the regeneration of amine-based solution absorption processes. Thus, nitrogen-rich porous adsorbents show good regeneration properties without sacrificing high separation efficiency. As such, nitrogen-rich porous materials as highly promising CO2 adsorbents have been broadly fabricated and intensively investigated. This Focus Review highlights recent significant advances in nitrogen-rich porous materials for CCS. PMID:23744799

  17. Poly(ethylenimine)-Functionalized Monolithic Alumina Honeycomb Adsorbents for CO2 Capture from Air.

    PubMed

    Sakwa-Novak, Miles A; Yoo, Chun-Jae; Tan, Shuai; Rashidi, Fereshteh; Jones, Christopher W

    2016-07-21

    The development of practical and effective gas-solid contactors is an important area in the development of CO2 capture technologies. Target CO2 capture applications, such as postcombustion carbon capture and sequestration (CCS) from power plant flue gases or CO2 extraction directly from ambient air (DAC), require high flow rates of gas to be processed at low cost. Extruded monolithic honeycomb structures, such as those employed in the catalytic converters of automobiles, have excellent potential as structured contactors for CO2 adsorption applications because of the low pressure drop imposed on fluid moving through the straight channels of such structures. Here, we report the impregnation of poly(ethylenimine) (PEI), an effective aminopolymer reported commonly for CO2 separation, into extruded monolithic alumina to form structured CO2 sorbents. These structured sorbents are first prepared on a small scale, characterized thoroughly, and compared with powder sorbents with a similar composition. Despite consistent differences observed in the filling of mesopores with PEI between the monolithic and powder sorbents, their performance in CO2 adsorption is similar across a range of PEI contents. A larger monolithic cylinder (1 inch diameter, 4 inch length) is evaluated under conditions closer to those that might be used in large-scale applications and shows a similar performance to the smaller monoliths and powders tested initially. This larger structure is evaluated over five cycles of CO2 adsorption and steam desorption and demonstrates a volumetric capacity of 350 molCO2  m-3monolith and an equilibration time of 350 min under a 0.4 m s(-1) linear flow velocity through the monolith channels using 400 ppm CO2 in N2 as the adsorption gas at 30 °C. This volumetric capacity surpasses that of a similar technology considered previously, which suggested that CO2 could be removed from air at an operating cost as low as $100 per ton. PMID:27304708

  18. CO2 capture enhancement in InOF-1 via the bottleneck effect of confined ethanol.

    PubMed

    Peralta, Ricardo A; Campos-Reales-Pineda, Alberto; Pfeiffer, Heriberto; Álvarez, J Raziel; Zárate, J Antonio; Balmaseda, Jorge; González-Zamora, Eduardo; Martínez, Ana; Martínez-Otero, Diego; Jancik, Vojtech; Ibarra, Ilich A

    2016-08-11

    CO2 capture of InOF-1 was enhanced 3.6-fold, at 1 bar and 30 °C, by confining EtOH within its pores. Direct visualisation by single crystal X-ray diffraction revealed that EtOH divides InOF-1 channels in wide sections separated by "bottlenecks" caused by EtOH molecules bonded to the μ2-OH functional groups of InOF-1. PMID:27469274

  19. COMBUSTION-ASSISTED CO2 CAPTURE USING MECC MEMBRANES

    SciTech Connect

    Brinkman, K.; Gray, J.

    2012-03-30

    Mixed Electron and Carbonate ion Conductor (MECC) membranes have been proposed as a means to separate CO{sub 2} from power plant flue gas. Here a modified MECC CO{sub 2} capture process is analyzed that supplements retentate pressurization and permeate evacuation as a means to create a CO{sub 2} driving force with a process assisted by the catalytic combustion of syngas on the permeate side of the membrane. The combustion reactions consume transported oxygen, making it unavailable for the backwards transport reaction. With this change, the MECC capture system becomes exothermic, and steam for electricity production may be generated from the waste heat. Greater than 90% of the CO{sub 2} in the flue gas may be captured, and a compressed CO{sub 2} product stream is produced. A fossil-fueled power plant using this process would consume 14% more fuel per unit electricity produced than a power plant with no CO{sub 2} capture system, and has the potential to meet U.S. DOE's goal that deployment of a CO{sub 2} capture system at a fossil-fueled power plant should not increase the cost of electricity from the combined facility by more than 30%.

  20. Hybrid Membrane/Absorption Process for Post-combustion CO2 Capture

    SciTech Connect

    Li, Shiguang; Shou, S.; Pyrzynski, Travis; Makkuni, Ajay; Meyer, Howard

    2013-12-31

    This report summarizes scientific/technical progress made for bench-scale membrane contactor technology for post-combustion CO2 capture from DOE Contract No. DE-FE-0004787. Budget Period 1 (BP1) membrane absorber, Budget Period 2 (BP2) membrane desorber and Budget Period 3 (BP3) integrated system and field testing studies have been completed successfully and met or exceeded the technical targets (≥ 90% CO2 removal and CO2 purity of 97% in one membrane stage). Significant breakthroughs are summarized below: BP1 research: The feasibility of utilizing the poly (ether ether ketone), PEEK, based hollow fiber contractor (HFC) in combination with chemical solvents to separate and capture at least 90% of the CO2 from simulated flue gases has been successfully established. Excellent progress has been made as we have achieved the BP1 goal: ≥ 1,000 membrane intrinsic CO2 permeance, ≥ 90% CO2 removal in one stage, ≤ 2 psi gas side pressure drop, and ≥ 1 (sec)-1 mass transfer coefficient. Initial test results also show that the CO2 capture performance, using activated Methyl Diethanol Amine (aMDEA) solvent, was not affected by flue gas contaminants O2 (~3%), NO2 (66 ppmv), and SO2 (145 ppmv). BP2 research: The feasibility of utilizing the PEEK HFC for CO2-loaded solvent regeneration has been successfully established High CO2 stripping flux, one order of magnitude higher than CO2 absorption flux, have been achieved. Refined economic evaluation based on BP1 membrane absorber and BP2 membrane desorber laboratory test data indicate that the CO2 capture costs are 36% lower than DOE’s benchmark amine absorption technology. BP3 research: A bench-scale system utilizing a membrane absorber and desorber was integrated into a continuous CO2 capture process using contactors containing 10 to 20 ft2 of membrane area. The integrated process operation was stable through a 100-hour laboratory test, utilizing a simulated flue gas stream. Greater than 90% CO2 capture combined with 97

  1. Amine-Oxide Hybrid Materials for CO2 Capture from Ambient Air.

    PubMed

    Didas, Stephanie A; Choi, Sunho; Chaikittisilp, Watcharop; Jones, Christopher W

    2015-10-20

    Oxide supports functionalized with amine moieties have been used for decades as catalysts and chromatographic media. Owing to the recognized impact of atmospheric CO2 on global climate change, the study of the use of amine-oxide hybrid materials as CO2 sorbents has exploded in the past decade. While the majority of the work has concerned separation of CO2 from dilute mixtures such as flue gas from coal-fired power plants, it has been recognized by us and others that such supported amine materials are also perhaps uniquely suited to extract CO2 from ultradilute gas mixtures, such as ambient air. As unique, low temperature chemisorbents, they can operate under ambient conditions, spontaneously extracting CO2 from ambient air, while being regenerated under mild conditions using heat or the combination of heat and vacuum. This Account describes the evolution of our activities on the design of amine-functionalized silica materials for catalysis to the design, characterization, and utilization of these materials in CO2 separations. New materials developed in our laboratory, such as hyperbranched aminosilica materials, and previously known amine-oxide hybrid compositions, have been extensively studied for CO2 extraction from simulated ambient air (400 ppm of CO2). The role of amine type and structure (molecular, polymeric), support type and structure, the stability of the various compositions under simulated operating conditions, and the nature of the adsorbed CO2 have been investigated in detail. The requirements for an effective, practical air capture process have been outlined and the ability of amine-oxide hybrid materials to meet these needs has been discussed. Ultimately, the practicality of such a "direct air capture" process is predicated not only on the physicochemical properties of the sorbent, but also how the sorbent operates in a practical process that offers a scalable gas-solid contacting strategy. In this regard, the utility of low pressure drop monolith

  2. A single-ligand ultra-microporous MOF for precombustion CO2 capture and hydrogen purification

    PubMed Central

    Nandi, Shyamapada; De Luna, Phil; Daff, Thomas D.; Rother, Jens; Liu, Ming; Buchanan, William; Hawari, Ayman I.; Woo, Tom K.; Vaidhyanathan, Ramanathan

    2015-01-01

    Metal organic frameworks (MOFs) built from a single small ligand typically have high stability, are rigid, and have syntheses that are often simple and easily scalable. However, they are normally ultra-microporous and do not have large surface areas amenable to gas separation applications. We report an ultra-microporous (3.5 and 4.8 Å pores) Ni-(4-pyridylcarboxylate)2 with a cubic framework that exhibits exceptionally high CO2/H2 selectivities (285 for 20:80 and 230 for 40:60 mixtures at 10 bar, 40°C) and working capacities (3.95 mmol/g), making it suitable for hydrogen purification under typical precombustion CO2 capture conditions (1- to 10-bar pressure swing). It exhibits facile CO2 adsorption-desorption cycling and has CO2 self-diffusivities of ~3 × 10−9 m2/s, which is two orders higher than that of zeolite 13X and comparable to other top-performing MOFs for this application. Simulations reveal a high density of binding sites that allow for favorable CO2-CO2 interactions and large cooperative binding energies. Ultra-micropores generated by a small ligand ensures hydrolytic, hydrostatic stabilities, shelf life, and stability toward humid gas streams. PMID:26824055

  3. Measurement, standards, and data needs for CO2 capture materials: a critical review.

    PubMed

    Espinal, Laura; Poster, Dianne L; Wong-Ng, Winnie; Allen, Andrew J; Green, Martin L

    2013-01-01

    The commercial deployment of cost-effective carbon capture technology is hindered partially by the lack of a proper suite of materials-related measurements, standards, and data, which would provide critical information for the systematic design, evaluation, and performance of CO2 separation materials. Based on a literature search and conversations with the carbon capture community, we review the current status of measurements, standards, and data for the three major carbon capture materials in use today: solvents, solid sorbents, and membranes. We highlight current measurement, standards and data activities aimed to advance the development and use of carbon capture materials and major research needs that are critical to meet if innovation in carbon capture materials is to be achieved. The review reveals that although adsorbents are considered to have great potential to reduce carbon capture cost, there is no consensus on the experimental parameters to be used for evaluating sorbent properties. Another important finding is the lack of in situ experimental tools for the structural characterization of solid porous materials during CO2 adsorption, and computational methods that would enable a materials-by-design approach for their development. PMID:24060087

  4. CO2 Capture from the Air: Technology Assessment and Implications for Climate Policy

    NASA Astrophysics Data System (ADS)

    Keith, D. W.

    2002-05-01

    It is physically possible to capture CO2 directly from the air and immobilize it in geological structures. Today, there are no large-scale technologies that achieve air capture at reasonable cost. Yet, strong arguments suggest that it will comparatively easy to develop practical air capture technologies on the timescales relevant to climate policy [1]. This paper first analyzes the cost of air capture and then assesses the implications for climate policy. We first analyze the lower bound on the cost needed for air capture, describing the thermodynamic and physical limits to the use of energy and land. We then compare the costs of air capture to the cost of capture from combustion exhaust streams. While the intrinsic minimum energy requirement is larger for air capture, we argue that air capture has important structural advantages, such as the reduction of transport costs and the larger potential for economies of scale. These advantages suggest that, in the long-run air capture be competitive with other methods of achieving deep emissions reductions. We provide a preliminary engineering-economic analysis of an air capture system based on CaO to CaCO3 chemical looping [1]. We analyze the possibility of doing the calcination in a modified pressurized fluidized bed combustor (PFBC) burning coal in a CO2 rich atmosphere with oxygen supplied by an air separation unit. The CaCO3-to-coal ratio would be ~2:1 and the system would be nearly thermally neutral. PFBC systems have been demonstrated at capacities of over 100 MW. Such systems already include CaCO3 injection for sulfur control, and operate at suitable temperatures and pressures for calcination. We assess the potential to recover heat from the dissolution of CaO in order to reduce the overall energy requirements. We analyze the possibility of adapting existing large water/air heat exchangers for use as contacting systems to capture CO2 from the air using the calcium hydroxide solution. The implications of air capture

  5. Progress Towards Commercialization of Electrochemical Membrane Technology for CO2 Capture and Power Generation

    SciTech Connect

    Ghezel-Ayagh, Hossein; Jolly, Stephen; DiNitto, M.; Hunt, Jennifer; Patel, Dilip; Steen, William A.; Richardson, C. F.; Marina, Olga A.; Pederson, Larry R.

    2014-03-01

    To address the concerns about climate change resulting from emission of CO2 by coal-fueled power plants, FuelCell Energy, Inc. has developed Combined Electric Power and Carbon-dioxide Separation (CEPACS) system concept, as a novel solution for greenhouse gas emission reduction. The CEPACS system utilizes Electrochemical Membrane (ECM) technology derived from the Company’s well established Direct FuelCell® products. The system concept works as two devices in one: it separates the CO2 from the exhaust of other plants and simultaneously, using a supplementary fuel, produces electric power at high efficiency. FCE is currently evaluating the use of ECM to cost effectively separate CO2 from the flue gas of coal fired power plants under a U.S. Department of Energy contract. The overarching objective of the project is to verify that the ECM can achieve at least 90% CO2 capture from flue gas of a PC plant with no more than 35% increase in the cost of electricity. The specific objectives and related activities presently ongoing for the project include: 1) conduct bench scale tests of ECM and 2) evaluate the effects of impurities present in the coal plant flue gas by laboratory scale performance tests of the membrane.

  6. Adsorption mechanism of graphene-like ZnO monolayer towards CO2 molecules: enhanced CO2 capture

    NASA Astrophysics Data System (ADS)

    Rao, G. S.; Hussain, T.; Islam, M. S.; Sagynbaeva, M.; Gupta, D.; Panigrahi, P.; Ahuja, R.

    2016-01-01

    This work aims to efficiently capture CO2 on two-dimensional (2D) nanostructures for effective cleaning of our atmosphere and purification of exhausts coming from fuel engines. Here, we have performed extensive first principles calculations based on density functional theory (DFT) to investigate the interaction of CO2 on a recently synthesized ZnO monolayer (ZnO-ML) in its pure, defected and functionalized form. A series of rigorous calculations yielded the most preferential binding configurations of the CO2 gas molecule on a ZnO-ML. It is observed that the substitution of one oxygen atom with boron, carbon and nitrogen on the ZnO monolayer resulted into enhanced CO2 adsorption. Our calculations show an enriched adsorption of CO2 on the ZnO-ML when substituting with foreign atoms like B, C and N. The improved adsorption energy of CO2 on ZnO suggests the ZnO-ML could be a promising candidate for future CO2 capture.

  7. Predicting the ultimate potential of natural gas SOFC power cycles with CO2 capture - Part B: Applications

    NASA Astrophysics Data System (ADS)

    Campanari, Stefano; Mastropasqua, Luca; Gazzani, Matteo; Chiesa, Paolo; Romano, Matteo C.

    2016-09-01

    An important advantage of solid oxide fuel cells (SOFC) as future systems for large scale power generation is the possibility of being efficiently integrated with processes for CO2 capture. Focusing on natural gas power generation, Part A of this work assessed the performances of advanced pressurised and atmospheric plant configurations (SOFC + GT and SOFC + ST, with fuel cell integration within a gas turbine or a steam turbine cycle) without CO2 separation. This Part B paper investigates such kind of power cycles when applied to CO2 capture, proposing two ultra-high efficiency plant configurations based on advanced intermediate-temperature SOFCs with internal reforming and low temperature CO2 separation process. The power plants are simulated at the 100 MW scale with a set of realistic assumptions about FC performances, main components and auxiliaries, and show the capability of exceeding 70% LHV efficiency with high CO2 capture (above 80%) and a low specific primary energy consumption for the CO2 avoided (1.1-2.4 MJ kg-1). Detailed results are presented in terms of energy and material balances, and a sensitivity analysis of plant performance is developed vs. FC voltage and fuel utilisation to investigate possible long-term improvements. Options for further improvement of the CO2 capture efficiency are also addressed.

  8. Process for CO2 Capture Using Ionic Liquid That Exhibits Phase Change

    SciTech Connect

    Eisinger, RS; Keller, GE

    2014-11-01

    A novel process for capturing carbon dioxide from the flue gas of a coal-fired power plant has been shown to reduce parasitic power consumption substantially. The process employs an ionic liquid created at the University of Notre Dame that has a high capacity for absorbing CO2 by chemical reaction. A distinguishing property of this ionic liquid is that it changes phase from solid to liquid upon reaction with CO2. The process uses heat generated by this phase transition to lower parasitic power consumption. The driving force for CO2 separation is a combination of temperature and pressure differences; the process could even work without the addition of heat. A realistic process was created to capture CO2 efficiently. Computer simulation of the process enabled calculation of viable process conditions and power usage. The main concepts of the process were shown to work using a lab-scale apparatus. Parasitic power consumes 23% of net power generation, 55% lower than that of the monoethanolamine (MEA) process. However, capital cost is higher. The cost of electricity (COE) is 28% lower than that of the MEA process.

  9. Application of amine-tethered solid sorbents for direct CO2 capture from the ambient air.

    PubMed

    Choi, Sunho; Drese, Jeffrey H; Eisenberger, Peter M; Jones, Christopher W

    2011-03-15

    While current carbon capture and sequestration (CCS) technologies for large point sources can help address the impact of CO(2) buildup on global climate change, these technologies can at best slow the rate of increase of the atmospheric CO(2) concentration. In contrast, the direct CO(2) capture from ambient air offers the potential to be a truly carbon negative technology. We propose here that amine-based solid adsorbents have significant promise as key components of a hypothetical air capture process. Specifically, the CO(2) capture characteristics of hyperbranched aminosilica (HAS) materials are evaluated here using CO(2) mixtures that simulate ambient atmospheric concentrations (400 ppm CO(2) = "air capture") as well as more traditional conditions simulating flue gas (10% CO(2)). The air capture experiments demonstrate that the adsorption capacity of HAS adsorbents are only marginally influenced even with a significant dilution of the CO(2) concentration by a factor of 250, while capturing CO(2) reversibly without significant degradation of performance in multicyclic operation. These results suggest that solid amine-based air capture processes have the potential to be an effective approach to extracting CO(2) from the ambient air. PMID:21323309

  10. Amorphous Silk Fibroin Membranes for Separation of CO2

    NASA Technical Reports Server (NTRS)

    Aberg, Christopher M.; Patel, Anand K.; Gil, Eun Seok; Spontak, Richard J.; Hagg, May-Britt

    2009-01-01

    Amorphous silk fibroin has shown promise as a polymeric material derivable from natural sources for making membranes for use in removing CO2 from mixed-gas streams. For most applications of silk fibroin, for purposes other than gas separation, this material is used in its highly crystalline, nearly natural form because this form has uncommonly high tensile strength. However, the crystalline phase of silk fibroin is impermeable, making it necessary to convert the material to amorphous form to obtain the high permeability needed for gas separation. Accordingly, one aspect of the present development is a process for generating amorphous silk fibroin by treating native silk fibroin in an aqueous methanol/salt solution. The resulting material remains self-standing and can be prepared as thin film suitable for permeation testing. The permeability of this material by pure CO2 has been found to be highly improved, and its mixed-gas permeability has been found to exceed the mixed-gas permeabilities of several ultrahigh-CO2-permeable synthetic polymers. Only one of the synthetic polymers poly(trimethylsilylpropyne) [PTMSP] may be more highly permeable by CO2. PTMSP becomes unstable with time, whereas amorphous silk should not, although at the time of this reporting this has not been conclusively proven.

  11. Highly optimized CO2 capture by inexpensive nanoporous covalent organic polymers and their amine composites.

    PubMed

    Patel, Hasmukh A; Yavuz, Cafer T

    2015-01-01

    Carbon dioxide (CO2) storage and utilization requires effective capture strategies that limit energy penalties. Polyethylenimine (PEI)-impregnated covalent organic polymers (COPs) with a high CO2 adsorption capacity are successfully prepared in this study. A low cost COP with a high specific surface area is suitable for PEI loading to achieve high CO2 adsorption, and the optimal PEI loading is 36 wt%. Though the adsorbed amount of CO2 on amine impregnated COPs slightly decreased with increasing adsorption temperature, CO2/N2 selectivity is significantly improved at higher temperatures. The adsorption of CO2 on the sorbent is very fast, and a sorption equilibrium (10% wt) was achieved within 5 min at 313 K under the flow of simulated flue gas streams. The CO2 capture efficiency of this sorbent is not affected under repetitive adsorption-desorption cycles. The highest CO2 capture capacity of 75 mg g(-1) at 0.15 bar is achieved under dry CO2 capture however it is enhanced to 100 mg g(-1) in the mixed gas flow containing humid 15% CO2. Sorbents were found to be thermally stable up to at least 200 °C. TGA and FTIR studies confirmed the loading of PEIs on COPs. This sorbent with high and fast CO2 sorption exhibits a very promising application in direct CO2 capture from flue gas. PMID:26388535

  12. Synthesis, characterization and application of alkanolamidines and alkanolguanidines in CO(2) capture

    SciTech Connect

    Koech, Phillip K; Heldebrant, David J; Lee, Suh-Jane; Rainbolt, James E; Smurthwaite, Tricia D

    2011-03-01

    Global carbon dioxide (CO2) emission to the atmosphere is partly responsible for climate change. In order to mitigate these environmental effects CO2 capture and storage is required. Solvents currently used for this application are the energy intensive aqueous amines. Here we present the synthesis, characterization and CO2 uptake of new advanced solvents called alkanolamidines and alkanolguanidines otherwise known as CO2-binding organic Liquids (CO2BOLs). These solvents have been designed to have decreased vapor pressure and low viscosity in order to increase the CO2 uptake capacity while minimizing evaporative losses. Alkanolamidines were synthesized in 1-3 steps from commercially available materials. These compounds bind CO2 chemically via the alcohol moiety forming zwitterionic alkylcarbonates. The alkanolamidines can be regenerated thermally by heating the alkylcarbonate to 75 °C. CO2 binding capacities up to 10 wt% were achieved using these compounds. These compounds have the potential to be energy efficient CO2 capture solvents.

  13. Self-supported fibrous porous aromatic membranes for efficient CO2/N2 separations.

    PubMed

    Meng, Lingbo; Zou, Xiaoqin; Guo, Shukun; Ma, Heping; Zhao, Yongnan; Zhu, Guangshan

    2015-07-22

    In this paper, we describe a new synthesis protocol for the preparation of self-supported hollow fiber membranes composed of porous aromatic framework PAF-56P and PSF. PAF-56P was facilely prepared by the cross-coupling reaction of triangle-shaped cyanuric chloride and linear p-terophenyl monomers. The prepared PAF-56P material possesses an extended conjugated network, the structure of which is confirmed by nuclear magnetic resonance and infrared characterizations, as well as a permanent porosity with a BET surface area of 553.4 m(2) g(-1) and a pore size of 1.2 nm. PAF-56P was subsequently integrated with PSF matrix into PAF-56P/PSF asymmetric hollow fiber membranes via the dry jet-wet quench method employing PAF-56P/PSF suspensions. Scanning electron microscopy studies show that PAF-56P particles are embedded in the PSF matrix to form continuous membranes. Fabricated PAF-56P/PSF membranes were further exploited for CO2 capture, which was exemplified by gas separations of CO2/N2 mixtures. The PAF-56P/PSF membranes show a high selectivity of CO2 over N2 with a separation factor of 38.9 due to the abundant nitrogen groups in the PAF-56P framework. A preferred permeance for CO2 in the binary CO2/N2 gas mixture is obtained in the range of 93-141 GPU due to the large CO2 adsorption capacity and a large pore size of PAF-56P. Additionally, PAF-56P/PSF membranes exhibit excellent thermal and mechanical stabilities, which were examined by thermal analysis and gas separation tests with the dependencies of temperatures and pressures. The merits of high selectivity for CO2, good stability, and easy scale up make PAF-56P/PSF hollow fiber membranes of great interest for the industrial separations of CO2 from the gas exhausts. PMID:26120972

  14. Hierarchical Mesoporous Metal-Organic Frameworks for Enhanced CO2 Capture.

    PubMed

    Mao, Yiyin; Chen, Danke; Hu, Pan; Guo, Yi; Ying, Yulong; Ying, Wen; Peng, Xinsheng

    2015-10-19

    Hierarchical porous materials are promising for catalyst, separation and sorption applications. A ligand-assisted etching process is developed for template-free synthesis of hierarchical mesoporous MOFs as single crystals and well-intergrown membranes at 40 °C. At 223 K, the hierarchical porous structures significantly improve the CO2 capture capacity of HKUST-1 by more than 44 % at pressures up to 20 kPa and 13 % at 100 kPa. Even at 323 K, the enhancement of CO2 uptake is above 25 % at pressures up to 20 kPa and 7 % at 100 kPa. The mesoporous structures not only enhance the CO2 uptake capacity but also improve the diffusion and mass transportation of CO2 . Similarly, well-intergrown mesoporous HKUST-1 membranes are synthesized, which hold the potential for film-like porous devices. Mesoporous MOF-5 crystals are also obtained by a similar ligand-assisted etching process. This may provide a facile way to prepare hierarchical porous MOF single crystals and membranes for wide-ranging applications. PMID:26471435

  15. Atmospheric CO2 capture by algae: Negative carbon dioxide emission path.

    PubMed

    Moreira, Diana; Pires, José C M

    2016-09-01

    Carbon dioxide is one of the most important greenhouse gas, which concentration increase in the atmosphere is associated to climate change and global warming. Besides CO2 capture in large emission point sources, the capture of this pollutant from atmosphere may be required due to significant contribution of diffuse sources. The technologies that remove CO2 from atmosphere (creating a negative balance of CO2) are called negative emission technologies. Bioenergy with Carbon Capture and Storage may play an important role for CO2 mitigation. It represents the combination of bioenergy production and carbon capture and storage, keeping carbon dioxide in geological reservoirs. Algae have a high potential as the source of biomass, as they present high photosynthetic efficiencies and high biomass yields. Their biomass has a wide range of applications, which can improve the economic viability of the process. Thus, this paper aims to assess the atmospheric CO2 capture by algal cultures. PMID:27005790

  16. Efficient electrochemical refrigeration power plant using natural gas with ∼100% CO2 capture

    NASA Astrophysics Data System (ADS)

    Al-musleh, Easa I.; Mallapragada, Dharik S.; Agrawal, Rakesh

    2015-01-01

    We propose an efficient Natural Gas (NG) based Solid Oxide Fuel Cell (SOFC) power plant equipped with ∼100% CO2 capture. The power plant uses a unique refrigeration based process to capture and liquefy CO2 from the SOFC exhaust. The capture of CO2 is carried out via condensation and purification using two rectifying columns operating at different pressures. The uncondensed gas mixture, comprising of relatively high purity unconverted fuel, is recycled to the SOFC and found to boost the power generation of the SOFC by 22%, when compared to a stand alone SOFC. If Liquefied Natural Gas (LNG) is available at the plant gate, then the refrigeration available from its evaporation is used for CO2 Capture and Liquefaction (CO2CL). If NG is utilized, then a Mixed Refrigerant (MR) vapor compression cycle is utilized for CO2CL. Alternatively, the necessary refrigeration can be supplied by evaporating the captured liquid CO2 at a lower pressure, which is then compressed to supercritical pressures for pipeline transportation. From rigorous simulations, the power generation efficiency of the proposed processes is found to be 70-76% based on lower heating value (LHV). The benefit of the proposed processes is evident when the efficiency of 73% for a conventional SOFC-Gas turbine power plant without CO2 capture is compared with an equivalent efficiency of 71.2% for the proposed process with CO2CL.

  17. Feasibility study of algae-based CO2 capture

    EPA Science Inventory

    Abstract: The biomass of microalgae contains approximately 50% carbon, which is commonly obtained from the atmosphere, but can also be taken from commercial sources that produce CO2, such as coal-fired power plants. A study of operational demonstration projects is being underta...

  18. Feasibility study of algae-based CO2 capture

    EPA Science Inventory

    The biomass of microalgae contains approximately 50% carbon, which is commonly obtained from the atmosphere, but can also be taken from commercial sources that produce CO2, such as coal-fired power plants. A study of operational demonstration projects is being undertaken to eval...

  19. SYSTEM LEVEL IMPLICATIONS OF FLEXIBLE CO2 CAPTURE OPERATION

    EPA Science Inventory

    In ERCOT, turning flexible CO2 capture systems off during infrequent periods of peak electricity demand can avoid hundreds of millions to billions of dollars in capital costs to replace the power output lost to CO2 capture energy requirements.  When CO...

  20. Effect of dolomite decomposition under CO2 on its multicycle CO2 capture behaviour under calcium looping conditions.

    PubMed

    de la Calle Martos, Antonio; Valverde, Jose Manuel; Sanchez-Jimenez, Pedro E; Perejón, Antonio; García-Garrido, Cristina; Perez-Maqueda, Luis A

    2016-06-28

    One of the major drawbacks that hinder the industrial competitiveness of the calcium looping (CaL) process for CO2 capture is the high temperature (∼930-950 °C) needed in practice to attain full calcination of limestone in a high CO2 partial pressure environment for short residence times as required. In this work, the multicycle CO2 capture performance of dolomite and limestone is analysed under realistic CaL conditions and using a reduced calcination temperature of 900 °C, which would serve to mitigate the energy penalty caused by integration of the CaL process into fossil fuel fired power plants. The results show that the fundamental mechanism of dolomite decomposition under CO2 has a major influence on its superior performance compared to limestone. The inert MgO grains resulting from dolomite decomposition help preserve a nanocrystalline CaO structure wherein carbonation in the solid-state diffusion controlled phase is promoted. The major role played by the dolomite decomposition mechanism under CO2 is clearly demonstrated by the multicycle CaO conversion behaviour observed for samples decomposed at different preheating rates. Limestone decomposition at slow heating rates yields a highly crystalline and poorly reactive CaCO3 structure that requires long periods to fully decarbonate and shows a severely reduced capture capacity in subsequent cycles. On the other hand, the nascent CaCO3 produced after dolomite half-decomposition consists of nanosized crystals with a fast decarbonation kinetics regardless of the preheating rate, thus fully decomposing from the very first cycle at a reduced calcination temperature into a CaO skeleton with enhanced reactivity as compared to limestone derived CaO. PMID:27253328

  1. Reducing the cost of Ca-based direct air capture of CO2.

    PubMed

    Zeman, Frank

    2014-10-01

    Direct air capture, the chemical removal of CO2 directly from the atmosphere, may play a role in mitigating future climate risk or form the basis of a sustainable transportation infrastructure. The current discussion is centered on the estimated cost of the technology and its link to "overshoot" trajectories, where atmospheric CO2 levels are actively reduced later in the century. The American Physical Society (APS) published a report, later updated, estimating the cost of a one million tonne CO2 per year air capture facility constructed today that highlights several fundamental concepts of chemical air capture. These fundamentals are viewed through the lens of a chemical process that cycles between removing CO2 from the air and releasing the absorbed CO2 in concentrated form. This work builds on the APS report to investigate the effect of modifications to the air capture system based on suggestions in the report and subsequent publications. The work shows that reduced carbon electricity and plastic packing materials (for the contactor) may have significant effects on the overall price, reducing the APS estimate from $610 to $309/tCO2 avoided. Such a reduction does not challenge postcombustion capture from point sources, estimated at $80/tCO2, but does make air capture a feasible alternative for the transportation sector and a potential negative emissions technology. Furthermore, air capture represents atmospheric reductions rather than simply avoided emissions. PMID:25207956

  2. NREL's Cyanobacteria Engineering Shortens Biofuel Production Process, Captures CO2

    SciTech Connect

    2015-09-01

    This highlight describes NREL's work to systematically analyze the flow of energy in a photosynthetic microbe and show how the organism adjusts its metabolism to meet the increased energy demand for making ethylene. This work successfully demonstrates that the organism could cooperate by stimulating photosynthesis. The results encourage further genetic engineering for the conversion of CO2 to biofuels and chemicals. This highlight is being developed for the September 2015 Alliance S&T Board meeting. biofuels and chemicals. This highlight is being developed for the September 2015 Alliance S&T Board meeting.

  3. NUCLEAR POWERED CO2 CAPTURE FROM THE ATMOSPHERE

    SciTech Connect

    Sherman, S

    2008-09-22

    A process for capturing CO{sub 2} from the atmosphere was recently proposed. This process uses a closed cycle of sodium and calcium hydroxide, carbonate, and oxide transformations to capture dilute CO{sub 2} from the atmosphere and to generate a concentrated stream of CO{sub 2} that is amenable to sequestration or subsequent chemical transformations. In one of the process steps, a fossil-fueled lime kiln is needed, which reduces the net CO{sub 2} capture of the process. It is proposed to replace the fossil-fueled lime kiln with a modified kiln heated by a high-temperature nuclear reactor. This will have the effect of eliminating the use of fossil fuels for the process and increasing the net CO{sub 2} capture. Although the process is suitable to support sequestration, the use of a nuclear power source for the process provides additional capabilities, and the captured CO{sub 2} may be combined with nuclear-produced hydrogen to produce liquid fuels via Fischer-Tropsch synthesis or other technologies. Conceivably, such plants would be carbon-neutral, and could be placed virtually anywhere without being tied to fossil fuel sources or geological sequestration sites.

  4. Ambient CO2 capture and storage in bioelectrochemically mediated wastewater treatment.

    PubMed

    Huang, Zhe; Jiang, Daqian; Lu, Lu; Ren, Zhiyong Jason

    2016-09-01

    This study reports that wastewater can be used to capture and store CO2 directly from ambient air and produce energy. The proof-of-concept system consisted of an ion exchange resin column that captures and concentrates ambient CO2 using a moisture-driven cycle. The concentrated CO2 was then transferred into a microbial electrochemical carbon capture (MECC) reactor for carbon sequestration and hydrogen production. Data from an average batch cycle showed that approximately 8mmol/L CO2 was captured in the MECC cathode when 0.14g/LCOD was removed in the anode. With 90% hydrogen conversion efficiency, the energy intensity and CO2 absorption from the process could be 11.3kJ/gCOD and 0.49gCO2/gCOD respectively. If the proposed process is applied, over 68milliontons of atmospheric CO2 can be captured yearly during wastewater treatment in the US, which equates to significant economic values if CO2 taxes were to be implemented more widely. PMID:27020397

  5. Supra-molecular networks for CO2 capture

    NASA Astrophysics Data System (ADS)

    Sadowski, Jerzy; Kestell, John

    Utilizing capabilities of low-energy electron microscopy (LEEM) for non-destructive interrogation of the real-time molecular self-assembly, we have investigated supramolecular systems based on carboxylic acid-metal complexes, such as trimesic and mellitic acid, doped with transition metals. Such 2D networks can act as host systems for transition-metal phthalocyanines (MPc; M = Fe, Ti, Sc). The electrostatic interactions of CO2 molecules with transition metal ions can be tuned by controlling the type of TM ion and the size of the pore in the host network. We further applied infrared reflection-absorption spectroscopy (IRRAS) to determine of the molecular orientation of the functional groups and the whole molecule in the 2D monolayers of carboxylic acid. The kinetics and mechanism of the CO2 adsorption/desorption on the 2D molecular network, with and without the TM ion doping, have been also investigated. This research used resources of the Center for Functional Nanomaterials, which is the U.S. DOE Office of Science User Facility, at Brookhaven National Laboratory under Contract No. DE-SC0012704.

  6. Integrating MEA Regeneration with CO2 Compression and Peaking to Reduce CO2 Capture Costs

    SciTech Connect

    Kevin S. Fisher; Carrie Beitler; Curtis Rueter; Katherine Searcy; Dr. Gary Rochelle; Dr. Majeed Jassim

    2005-06-09

    Capturing CO{sub 2} from coal-fired power plants is a necessary component of any large-scale effort to reduce anthropogenic CO{sub 2} emissions. Conventional absorption/stripping with monoethanolamine (MEA) or similar solvents is the most likely current process for capturing CO{sub 2} from the flue gas at these facilities. However, one of the largest problems with MEA absorption/stripping is that conventional process configurations have energy requirements that result in large reductions in the net power plant output. Several alternative process configurations for reducing these parasitic energy requirements were investigated in this research with the assistance of the Platte River Power Authority, based on recovering energy from the CO{sub 2} compression train and using that energy in the MEA regeneration step. In addition, the feasibility of selective operation of the amine system at a higher CO{sub 2} removal efficiency during non-peak electricity demand periods was also evaluated. Four process configurations were evaluated: A generic base case MEA system with no compression heat recovery, CO{sub 2} vapor recompression heat recovery, and multipressure stripping with and without vapor recompression heat recovery. These configurations were simulated using a rigorous rate-based model, and the results were used to prepare capital and operating cost estimates. CO{sub 2} capture economics are presented, and the cost of CO{sub 2} capture (cost per tonne avoided) is compared among the base case and the alternative process configurations. Cost savings per tonne of CO{sub 2} avoided ranged from 4.3 to 9.8 percent. Energy savings of the improved configurations (8-10%, freeing up 13 to 17 MW of power for sale to the grid based on 500 MW unit ) clearly outweighed the modest increases in capital cost to implement them; it is therefore likely that one of these improved configurations would be used whenever MEA-based (or similar) scrubbing technologies are implemented. In fact

  7. Covalent Triazine-Based Frameworks with Ultramicropores and High Nitrogen Contents for Highly Selective CO2 Capture.

    PubMed

    Wang, Keke; Huang, Hongliang; Liu, Dahuan; Wang, Chang; Li, Jinping; Zhong, Chongli

    2016-05-01

    Porous organic frameworks (POFs) are a class of porous materials composed of organic precursors linked by covalent bonds. The objective of this work is to develop POFs with both ultramicropores and high nitrogen contents for CO2 capture. Specifically, two covalent triazine-based frameworks (CTFs) with ultramicropores (pores of width <7 Å) based on short (fumaronitrile, FUM) and wide monomers (1,4-dicyanonaphthalene, DCN) were synthesized. The obtained CTF-FUM and CTF-DCN possess excellent chemical and thermal stability with ultramicropores of 5.2 and 5.4 Å, respectively. In addition, they exhibit excellent ability to selectively capture CO2 due to ultramicroporous nature. Especially, CTF-FUM-350 has the highest nitrogen content (27.64%) and thus the highest CO2 adsorption capacity (57.2 cc/g at 298 K) and selectivities for CO2 over N2 and CH4 (102.4 and 20.5 at 298 K, respectively) among all CTF-FUM and CTF-DCN. More impressively, as far as we know, the CO2/CH4 selectivity is larger than that of all reported CTFs and ranks in top 10 among all reported POFs. Dynamic breakthrough curves indicate that both CTFs could indeed separate gas mixtures of CO2/N2 and CO2/CH4 completely. PMID:27081869

  8. Reversible CO2 Capture by Conjugated Ionic Liquids through Dynamic Covalent Carbon-Oxygen Bonds.

    PubMed

    Pan, Mingguang; Cao, Ningning; Lin, Wenjun; Luo, Xiaoyan; Chen, Kaihong; Che, Siying; Li, Haoran; Wang, Congmin

    2016-09-01

    The strong chemisorption of CO2 is always accompanied by a high absorption enthalpy, and traditional methods to reduce the absorption enthalpy lead to decreased CO2 capacities. Through the introduction of a large π-conjugated structure into the anion, a dual-tuning approach for the improvement of CO2 capture by anion-functionalized ionic liquids (ILs) resulted in a high capacity of up to 0.96 molCO2  mol-1IL and excellent reversibility. The increased capacity and improved desorption were supported by quantum chemical calculations, spectroscopic investigations, and thermogravimetric analysis. The increased capacity may be a result of the strengthened dynamic covalent bonds in these π-electron-conjugated structures through anion aggregation upon the uptake of CO2 , and the improved desorption originates from the charge dispersion of interaction sites through the large π-electron delocalization. These results provide important insights into effective strategies for CO2 capture. PMID:27458723

  9. Phase-Changing Ionic Liquids: CO2 Capture with Ionic Liquids Involving Phase Change

    SciTech Connect

    2010-07-01

    IMPACCT Project: Notre Dame is developing a new CO2 capture process that uses special ionic liquids (ILs) to remove CO2 from the gas exhaust of coal-fired power plants. ILs are salts that are normally liquid at room temperature, but Notre Dame has discovered a new class of ILs that are solid at room temperature and change to liquid when they bind to CO2. Upon heating, the CO2 is released for storage, and the ILs re-solidify and donate some of the heat generated in the process to facilitate further CO2 release. These new ILs can reduce the energy required to capture CO2 from the exhaust stream of a coal-fired power plant when compared to state-ofthe- art technology.

  10. Hybrid Solvent-Membrane CO2 Capture: A Solvent/Membrane Hybrid Post-combustion CO2 Capture Process for Existing Coal-Fired Power Plants

    SciTech Connect

    2010-07-01

    IMPACCT Project: The University of Kentucky is developing a hybrid approach to capturing CO2 from the exhaust gas of coal-fired power plants. In the first, CO2 is removed as flue gas is passed through an aqueous ammonium-based solvent. In the second, carbon-rich solution from the CO2 absorber is passed through a membrane that is designed to selectively transport the bound carbon, enhancing its concentration on the permeate side. The team’s approach would combine the best of both membrane- and solventbased carbon capture technologies. Under the ARPA-E award, the team is enabling the membrane operation to be a drop-in solution.

  11. 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.

  12. Phosphonium salt incorporated hypercrosslinked porous polymers for CO2 capture and conversion.

    PubMed

    Wang, Jinquan; Wei Yang, Jason Gan; Yi, Guangshun; Zhang, Yugen

    2015-11-01

    Various novel hypercrosslinked porous polymers with phosphonium salt incorporated into their networks were developed. These porous materials have high BET surface areas (up to 1168 m(2) g(-1)) and can be used to selectively capture CO2 and efficiently convert CO2 into cyclic carbonates. PMID:26365361

  13. Polymer blend membranes for CO2 separation from natural gas

    NASA Astrophysics Data System (ADS)

    Mukhtar, H.; Mannan, H. A.; Minh, D.; Nasir, R.; Moshshim, D. F.; Murugesan, T.

    2016-06-01

    Polymeric membranes are dominantly used in industrial gas separation membrane processes. Enhancement in membranes permeability and/or selectivity is a key challenge faced by membrane researchers. The current work represents the effect of poyetherimide blending on separation performance of polysulfone membranes. Polysulfone/poyetherimide (PSF/PEI) blend flat sheet dense membranes were synthesized and tested for permeation analysis of CO2 and CH4 gases at 6, 8 and 10 bar pressure and 25oC temperature. Morphology and thermal properties of membranes were characterized by field emission scanning electron microscope (FESEM) and thermo gravimetric analysis (TGA) respectively. Blend membranes were dense and homogeneous as deduced from FESEM analysis. Thermal stability of synthesized blend membranes was maintained by blending with PEI as characterized by TGA results. Decrease in permeability of both gases was observed by the addition of PEI due to rigidity of PEI chains. Additionally, selectivity of synthesized blend membranes was enhanced by blending PEI and blend membranes show improved selectivity over pure PSF membrane. This new material has the capability to be used as gas separation membrane material.

  14. Carbon-Based Adsorbents for Postcombustion CO2 Capture: A Critical Review.

    PubMed

    Creamer, Anne Elise; Gao, Bin

    2016-07-19

    The persistent increase in atmospheric CO2 from anthropogenic sources makes research directed toward carbon capture and storage imperative. Current liquid amine absorption technology has several drawbacks including hazardous byproducts and a high-energy requirement for regeneration; therefore, research is ongoing to develop more practical methods for capturing CO2 in postcombustion scenarios. The unique properties of carbon-based materials make them specifically promising for CO2 adsorption at low temperature and moderate to high partial pressure. This critical review aims to highlight the development of carbon-based solid sorbents for postcombustion CO2 capture. Specifically, it provides an overview of postcombustion CO2 capture processes with solid adsorbents and discusses a variety of carbon-based materials that could be used. This review focuses on low-cost pyrogenic carbon, activated carbon (AC), and metal-carbon composites for CO2 capture. Further, it touches upon the recent progress made to develop metal organic frameworks (MOFs) and carbon nanomaterials and their general CO2 sorption potential. PMID:27257991

  15. CO2 CAPTURE BY ABSORPTION WITH POTASSIUM CARBONATE

    SciTech Connect

    Gary T. Rochelle; A. Frank Seibert; J. Tim Cullinane; Terraun Jones

    2003-01-01

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. Progress has been made in this reporting period on three subtasks. The rigorous Electrolyte Non-Random Two-Liquid (electrolyte-NRTL) model has been regressed to represent CO{sub 2} solubility in potassium carbonate/bicarbonate solutions. An analytical method for piperazine has been developed using a gas chromatograph. Funding has been obtained and equipment has been donated to provide for modifications of the existing pilot plant system with stainless steel materials.

  16. CO2 CAPTURE BY ABSORPTION WITH POTASSIUM CARBONATE

    SciTech Connect

    Gary T. Rochelle; Eric Chen; J. Tim Cullinane; Marcus Hillard; Babatunde Oyenekan

    2003-10-31

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. A rigorous thermodynamic model has been further developed with a standalone FORTRAN code to represent the CO{sub 2} vapor pressure and speciation of the new solvent. The welding work has initiated and will be completed for a revised startup of the pilot plant in February 2004.

  17. Detoxifying CO2 capture reclaimer waste by anaerobic digestion.

    PubMed

    Wang, Shuai; Hovland, Jon; Brooks, Steven; Bakke, Rune

    2014-01-01

    The decrease in toxicity of carbon capture reclaimer monoethanolamine (MEA) waste (MEAw) during anaerobic degradation of such waste together with easily degradable organics was investigated. Samples were collected from a bioreactor at steady state with 86 % organic chemical oxygen demand removal at room temperature, which had been running on MEAw for 2 years. The toxicity of the digester effluents were 126, 42 and 10 times lower than that of the MEAw to the tested freshwater trophic groups of Pseudokirchneriella subcapitata, Daphnia magna and embryos of Danio rerio, respectively. The toxicity of the tested taxonomic groups after anaerobic digestion was mainly attributed to the ammonia generated by the degradation of MEAw. PMID:24122630

  18. CO2 CAPTURE BY ABSORPTION WITH POTASSIUM CARBONATE

    SciTech Connect

    Gary T. Rochelle; Eric Chen; J. Tim Cullinane; Marcus Hilliard; Babatunde Oyenekan; Terraun Jones

    2003-07-28

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. A rigorous thermodynamic model has been further developed with a standalone FORTRAN code to represent the CO{sub 2} vapor pressure and speciation of the new solvent. Gas chromatography has been used to measure the oxidative degradation of piperazine. The heat exchangers for the pilot plant have been received. The modifications are on schedule for start-up in November 2003.

  19. CO2 CAPTURE BY ABSORPTION WITH POTASSIUM CARBONATE

    SciTech Connect

    Gary T. Rochelle; A. Frank Seibert

    2002-10-01

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. Progress has been made in this reporting period on three subtasks. A simple thermodynamic model has been developed to represent the CO{sub 2} vapor pressure and speciation of the new solvent. A rate model has been formulated to predict the CO{sub 2} flux with these solutions under absorber conditions. A process and instrumentation diagram and process flow diagram have been prepared for modifications of the existing pilot plant system.

  20. Superstructure-based optimal design of PSA cycles for post-combustion CO2 capture

    SciTech Connect

    Agarwal, A.; Biegler, L.; Zitney, S.

    2009-07-01

    Recent developments have shown pressure/vacuum swing adsorption (PSA/VSA) to be a promising option to effectively capture CO2 from flue gas streams. In most commercial PSA cycles, the weakly adsorbed component in the mixture is the desired product, and enriching the strongly adsorbed CO2 is not a concern. Thus, it is necessary to develop PSA processes specifically targeted to obtain pure strongly adsorbed component. So far, no systematic methodology has been suggested in the literature to design PSA cycles for high purity CO2 capture. This study addresses this need and presents a systematic optimization-based formulation to synthesize PSA cycles. In particular, a novel PSA superstructure is presented to design optimal PSA cycle configurations and evaluate CO2 capture strategies. The superstructure is rich enough to predict a number of different PSA operating steps. The bed connections in the superstructure are governed by timedependent control variables, which can be varied to realize most PSA operating steps. An optimal sequence of operating steps is achieved through the formulation of an optimal control problem with the partial differential and algebraic equations of the PSA system and the cyclic steady state condition. The superstructure approach is demonstrated for case studies related to post-combustion CO2 capture. In particular, optimal PSA cycles were synthesized which maximize CO2 recovery for a given purity, and minimize overall power consumption. The results show the potential of the superstructure to predict PSA cycles with up to 98% purity and recovery of CO2. Moreover, for recovery of around 85% and purity of over 90%, these cycles can recover CO2 from atmospheric flue gas with a low power consumption of 465 kWh/tonne CO2. The approach presented is, therefore, very promising and quite useful for evaluating the suitability of different adsorbents, feedstocks and operating strategies for PSA, and assessing its usefulness for CO2 capture.

  1. A superstructure-based optimal synthesis of PSA cycles for post-combustion CO2 capture

    SciTech Connect

    Agarwal, A.; Biegler, L.; Zitney, S.

    2010-07-01

    Recent developments have shown pressure/vacuum swing adsorption (PSA/VSA) to be a promising option to effectively capture CO2 from flue gas streams. In most commercial PSA cycles, the weakly adsorbed component in the mixture is the desired product, and enriching the strongly adsorbed CO2 is not a concern. On the other hand, it is necessary to concentrate CO2 to high purity to reduce CO2 sequestration costs and minimize safety and environmental risks. Thus, it is necessary to develop PSA processes specifically targeted to obtain pure strongly adsorbed component. A multitude of PSA/VSA cycles have been developed in the literature for CO2 capture from feedstocks low in CO2 concentration. However, no systematic methodology has been suggested to develop, evaluate, and optimize PSA cycles for high purity CO2 capture. This study presents a systematic optimization-based formulation to synthesize novel PSA cycles for a given application. In particular, a novel PSA superstructure is presented to design optimal PSA cycle configurations and evaluate CO2 capture strategies. The superstructure is rich enough to predict a number of different PSA operating steps. The bed connections in the superstructure are governed by time-dependent control variables, which can be varied to realize most PSA operating steps. An optimal sequence of operating steps is achieved through the formulation of an optimal control problem with the partial differential and algebraic equations of the PSA system and the cyclic steady state condition. Large-scale optimization capabilities have enabled us to adopt a complete discretization methodology to solve the optimal control problem as a largescale nonlinear program, using the nonlinear optimization solver IPOPT. The superstructure approach is demonstrated for case studies related to post-combustion CO2 capture. In particular, optimal PSA cycles were synthesized, which maximize CO2 recovery for a given purity, and minimize overall power consumption. The

  2. CO2 Capture by Absorption with Potassium Carbonate

    SciTech Connect

    Gary T. Rochelle; Eric Chen; Babatunde Oyenekan; Andrew Sexton; Jason Davis; Marcus Hilliard; Amornvadee Veawab

    2006-09-30

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. Ethylenediamine was detected in a degraded solution of MEA/PZ solution, suggesting that piperazine is subject to oxidation. Stripper modeling has demonstrated that vacuum strippers will be more energy efficient if constructed short and fat rather than tall and skinny. The matrix stripper has been identified as a configuration that will significantly reduce energy use. Extensive measurements of CO{sub 2} solubility in 7 m MEA at 40 and 60 C have confirmed the work by Jou and Mather. Corrosion of carbon steel without inhibitors increases from 19 to 181 mpy in lean solutions of 6.2 m MEA/PZ as piperazine increases from 0 to 3.1 m.

  3. CO2 Capture by Absorption with Potassium Carbonate

    SciTech Connect

    Gary T. Rochelle; Marcus Hilliard; Eric Chen; Babatunde Oyenekan; Ross Dugas; John McLees; Andrew Sexton; Daniel Ellenberger

    2005-10-26

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. Modeling of stripper performance suggests that vacuum stripping may be an attractive configuration for all solvents. Flexipac 1Y structured packing performs in the absorber as expected. It provides twice as much mass transfer area as IMTP No.40 dumped packing. Independent measurements of CO{sub 2} solubility give a CO{sub 2} loading that is 20% lower than that Cullinane's values with 3.6 m PZ at 100-120 C. The effective mass transfer coefficient (K{sub G}) in the absorber with 5 m K/2.5 m PZ appears to be 0 to 30% greater than that of 30 wt% MEA.

  4. CO2 Capture by Absorption with Potassium Carbonate

    SciTech Connect

    Gary T. Rochelle; Eric Chen; Babatunde Oyenekan; Andrew Sexton; Amorvadee Veawab

    2006-04-28

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. The final campaign of the pilot plant was completed in February 2006 with 5m K{sup +}/2.5m PZ and 6.4m K{sup +}/1.6m PZ using Flexipac AQ Style 20. The new cross-exchanger reduced the approach temperature to less than 9 C. Stripper modeling has demonstrated that a configuration with a ''Flashing Feed'' requires 6% less work that a simple stripper. The oxidative degradation of piperazine proceeds more slowly than that of monoethanolamine and produces ethylenediamine and other products. Uninhibited 5 m KHCO{sub 3}/2.5 m PZ corrodes 5 to 6 times faster that 30% MEA with 0.2 mol CO{sub 2}/mol MEA.

  5. CO2 Capture by Absorption with Potassium Carbonate

    SciTech Connect

    Gary T. Rochelle; Eric Chen; Babatunde Oyenekan; Andrew Sexton; Jason Davis; Marcus Hilliard; Amorvadee Veawab

    2006-07-28

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. The pilot plant data have been reconciled using 17% inlet CO{sub 2}. A rate-based model demonstrates that the stripper is primarily controlled by liquid film mast transfer resistance, with kinetics at vacuum and diffusion of reactants and products at normal pressure. An additional major unknown ion, probably glyoxylate, has been observed in MEA degradation. Precipitation of gypsum may be a feasible approach to removing sulphate from amine solutions and providing for simultaneous removal of CO{sub 2} and SO{sub 2}. Corrosion of carbon steel in uninhibited MEA solution is increased by increased amine concentration, by addition of piperazine, and by greater CO{sub 2} loading.

  6. CO2 CAPTURE BY ABSORPTION WITH POTASSIUM CARBONATE

    SciTech Connect

    Gary T. Rochelle; Eric Chen; Jennifer Lu; Babatunde Oyenekan; Ross Dugas

    2005-04-29

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. Stripper modeling suggests the energy requirement with a simple stripper will be about the same for 5 m K{sup +}/2.5 m PZ and 7 m MEA. Modeling with a generic solvent shows that the optimum heat of CO{sub 2} desorption to minimize heat duty lies between 15 and 25 kcal/gmol. On-line pH and density measurements are effective indicators of loading and total alkalinity for the K+/PZ solvent. The baseline pilot plant campaign with 30% MEA has been started.

  7. CO2 CAPTURE BY ABSORPTION WITH POTASSIUM CARBONATE

    SciTech Connect

    Gary T. Rochelle; Marcus Hilliard; Eric Chen; Babatunde Oyenekan; Ross Dugas; John McLees

    2005-07-31

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. The baseline campaign with 30% MEA has given heat duties from 40 to 70 kcal/gmol CO{sub 2} as predicted by the stripper model. The Flexipak 1Y structured packing gives significantly better performance than IMTP 40 duped packing in the absorber, but in the stripper the performance of the two packings is indistinguishable. The FTIR analyzer measured MEA volatility in the absorber represented by an activity coefficient of 0.7. In the MEA campaign the material balance closed with an average error of 3.5% and the energy balance had an average error of 5.9.

  8. CO2 Capture by Absorption with Potassium Carbonate

    SciTech Connect

    Gary T. Rochelle; Marcus Hilliard; Eric Chen; Babatunde Oyenekan; Ross Dugas; John McLees; Andrew Sexton; Amorvadee Veawab

    2005-01-26

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. In Campaign 3 of the pilot plant, the overall mass transfer coefficient for the stripper with 7 m MEA decreased from 0.06 to 0.01 mol/(m{sup 3}.s.kPa) as the rich loading increased from 0.45 to 0.6 mol CO{sub 2}/mol MEA. Anion chromatography has demonstrated that nitrate and nitrite are major degradation products of MEA and PZ with pure oxygen. In measurements with the high temperature FTIR in 7 m MEA the MEA vapor pressure varied from 2 to 20 Pa at 35 to 70 C. In 2.5 m PZ the PZ vapor pressure varied from 0.2 to 1 Pa from 37 to 70 C.

  9. CO2 CAPTURE BY ABSORPTION WITH POTASSIUM CARBONATE

    SciTech Connect

    Gary T. Rochelle; Eric Chen; J.Tim Cullinane; Marcus Hilliard; Jennifer Lu; Babatunde Oyenekan; Ross Dugas

    2004-07-29

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. CO{sub 2} mass transfer rates are second order in piperazine concentration and increase with ionic strength. Modeling of stripper performance suggests that 5 m K{sup +}/2.5 m PZ will require 25 to 46% less heat than 7 m MEA. The first pilot plant campaign was completed on June 24. The CO{sub 2} penetration through the absorber with 20 feet of Flexipac{trademark} 1Y varied from 0.6 to 16% as the inlet CO{sub 2} varied from 3 to 12% CO{sub 2} and the gas rate varied from 0.5 to 3 kg/m{sup 2}-s.

  10. Chemical transformation of CO2 during its capture by waste biomass derived biochars.

    PubMed

    Xu, Xiaoyun; Kan, Yue; Zhao, Ling; Cao, Xinde

    2016-06-01

    Biochar is a porous carbonaceous material with high alkalinity and rich minerals, making it possible for CO2 capture. In this study, biochars derived from pig manure, sewage sludge, and wheat straw were evaluated for their CO2 sorption behavior. All three biochars showed high sorption abilities for CO2, with the maximum capacities reaching 18.2-34.4 mg g(-1) at 25 °C. Elevating sorption temperature and moisture content promoted the transition of CO2 uptake from physical to chemical process. Mineral components such as Mg, Ca, Fe, K, etc. in biochar induced the chemical sorption of CO2 via the mineralogical reactions which occupied 17.7%-50.9% of the total sorption. FeOOH in sewage sludge biochar was transformed by sorbed CO2 into Fe(OH)2CO3, while the sorbed CO2 in pig manure biochar was precipitated as K2Ca(CO3)2 and CaMg(CO3)2, which resulted in a dominant increase of insoluble inorganic carbon in both biochars. For wheat straw biochar, sorbed CO2 induced CaCO3 transformed into soluble Ca(HCO3)2, which led to a dominant increase of soluble inorganic carbons. The results obtained from this study demonstrated that biochar as a unique carbonaceous material could distinctly be a promising sorbent for CO2 capture in which chemical sorption induced by mineralogical reactions played an important role. PMID:26995449

  11. The urgency of the development of CO2 capture from ambient air

    PubMed Central

    Lackner, Klaus S.; Brennan, Sarah; Matter, Jürg M.; Park, A.-H. Alissa; Wright, Allen; van der Zwaan, Bob

    2012-01-01

    CO2 capture and storage (CCS) has the potential to develop into an important tool to address climate change. Given society’s present reliance on fossil fuels, widespread adoption of CCS appears indispensable for meeting stringent climate targets. We argue that for conventional CCS to become a successful climate mitigation technology—which by necessity has to operate on a large scale—it may need to be complemented with air capture, removing CO2 directly from the atmosphere. Air capture of CO2 could act as insurance against CO2 leaking from storage and furthermore may provide an option for dealing with emissions from mobile dispersed sources such as automobiles and airplanes. PMID:22843674

  12. The urgency of the development of CO2 capture from ambient air.

    PubMed

    Lackner, Klaus S; Brennan, Sarah; Matter, Jürg M; Park, A-H Alissa; Wright, Allen; van der Zwaan, Bob

    2012-08-14

    CO(2) capture and storage (CCS) has the potential to develop into an important tool to address climate change. Given society's present reliance on fossil fuels, widespread adoption of CCS appears indispensable for meeting stringent climate targets. We argue that for conventional CCS to become a successful climate mitigation technology--which by necessity has to operate on a large scale--it may need to be complemented with air capture, removing CO(2) directly from the atmosphere. Air capture of CO(2) could act as insurance against CO(2) leaking from storage and furthermore may provide an option for dealing with emissions from mobile dispersed sources such as automobiles and airplanes. PMID:22843674

  13. CO2 CAPTURE BY ABSORPTION WITH POTASSIUM CARBONATE

    SciTech Connect

    Gary T. Rochelle; Eric Chen; Jennifer Lu; Babatunde Oyenekan; Ross Dugas

    2004-11-08

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. The stripper model with Aspen Custom Modeler and careful optimization of solvent rate suggests that 7 m MEA and 5 m K+/2.5 m PZ will be practically equivalent in energy requirement and optimum solution capacity. The multipressure stripper reduces energy consumption by 15% with a maximum pressure of 5 atm. The use of vanadium as a corrosion inhibitor will carry little risk of long-term environmental or health effects liability, but the disposal of solvent with vanadium will be subject to regulation, probably as a hazardous waste. Analysis of the pilot plant data from Campaign 1 has given values of the mass transfer coefficient consistent with the rate data from the wetted wall column. With a rich end pinch, 30% MEA should provide a capacity of 1.3-1.4 mole CO{sub 2}/kg solvent.

  14. CO2 Capture from Flue Gas by Phase Transitional Absorption

    SciTech Connect

    Liang Hu

    2009-06-30

    A novel absorption process called Phase Transitional Absorption was invented. What is the Phase Transitional Absorption? Phase Transitional Absorption is a two or multi phase absorption system, CO{sub 2} rich phase and CO{sub 2} lean phase. During Absorption, CO{sub 2} is accumulated in CO{sub 2} rich phase. After separating the two phases, CO{sub 2} rich phase is forward to regeneration. After regeneration, the regenerated CO{sub 2} rich phase combines CO{sub 2} lean phase to form absorbent again to complete the cycle. The advantage for Phase Transitional Absorption is obvious, significantly saving on regeneration energy. Because CO{sub 2} lean phase was separated before regeneration, only CO{sub 2} rich phase was forward to regeneration. The absorption system we developed has the features of high absorption rate, high loading and working capacity, low corrosion, low regeneration heat, no toxic to environment, etc. The process evaluation shows that our process is able to save 80% energy cost by comparing with MEA process.

  15. Comparative Assessment of Gasification Based Coal Power Plants with Various CO2 Capture Technologies Producing Electricity and Hydrogen.

    PubMed

    Mukherjee, Sanjay; Kumar, Prashant; Hosseini, Ali; Yang, Aidong; Fennell, Paul

    2014-02-20

    Seven different types of gasification-based coal conversion processes for producing mainly electricity and in some cases hydrogen (H2), with and without carbon dioxide (CO2) capture, were compared on a consistent basis through simulation studies. The flowsheet for each process was developed in a chemical process simulation tool "Aspen Plus". The pressure swing adsorption (PSA), physical absorption (Selexol), and chemical looping combustion (CLC) technologies were separately analyzed for processes with CO2 capture. The performances of the above three capture technologies were compared with respect to energetic and exergetic efficiencies, and the level of CO2 emission. The effect of air separation unit (ASU) and gas turbine (GT) integration on the power output of all the CO2 capture cases is assessed. Sensitivity analysis was carried out for the CLC process (electricity-only case) to examine the effect of temperature and water-cooling of the air reactor on the overall efficiency of the process. The results show that, when only electricity production in considered, the case using CLC technology has an electrical efficiency 1.3% and 2.3% higher than the PSA and Selexol based cases, respectively. The CLC based process achieves an overall CO2 capture efficiency of 99.9% in contrast to 89.9% for PSA and 93.5% for Selexol based processes. The overall efficiency of the CLC case for combined electricity and H2 production is marginally higher (by 0.3%) than Selexol and lower (by 0.6%) than PSA cases. The integration between the ASU and GT units benefits all three technologies in terms of electrical efficiency. Furthermore, our results suggest that it is favorable to operate the air reactor of the CLC process at higher temperatures with excess air supply in order to achieve higher power efficiency. PMID:24578590

  16. Comparative Assessment of Gasification Based Coal Power Plants with Various CO2 Capture Technologies Producing Electricity and Hydrogen

    PubMed Central

    2014-01-01

    Seven different types of gasification-based coal conversion processes for producing mainly electricity and in some cases hydrogen (H2), with and without carbon dioxide (CO2) capture, were compared on a consistent basis through simulation studies. The flowsheet for each process was developed in a chemical process simulation tool “Aspen Plus”. The pressure swing adsorption (PSA), physical absorption (Selexol), and chemical looping combustion (CLC) technologies were separately analyzed for processes with CO2 capture. The performances of the above three capture technologies were compared with respect to energetic and exergetic efficiencies, and the level of CO2 emission. The effect of air separation unit (ASU) and gas turbine (GT) integration on the power output of all the CO2 capture cases is assessed. Sensitivity analysis was carried out for the CLC process (electricity-only case) to examine the effect of temperature and water-cooling of the air reactor on the overall efficiency of the process. The results show that, when only electricity production in considered, the case using CLC technology has an electrical efficiency 1.3% and 2.3% higher than the PSA and Selexol based cases, respectively. The CLC based process achieves an overall CO2 capture efficiency of 99.9% in contrast to 89.9% for PSA and 93.5% for Selexol based processes. The overall efficiency of the CLC case for combined electricity and H2 production is marginally higher (by 0.3%) than Selexol and lower (by 0.6%) than PSA cases. The integration between the ASU and GT units benefits all three technologies in terms of electrical efficiency. Furthermore, our results suggest that it is favorable to operate the air reactor of the CLC process at higher temperatures with excess air supply in order to achieve higher power efficiency. PMID:24578590

  17. Evaluation of Solid Sorbents as a Retrofit Technology for CO2 Capture

    SciTech Connect

    Sjostrom, Sharon

    2015-09-30

    ADA completed a DOE-sponsored program titled Evaluation of Solid Sorbents as a Retrofit Technology for CO2 Capture under program DE-FE0004343. During this program, sorbents were analyzed for use in a post-combustion CO2 capture process. A supported amine sorbent was selected based upon superior performance to adsorb a greater amount of CO2 than the activated carbon sorbents tested. When the most ideal sorbent at the time was selected, it was characterized and used to create a preliminary techno-economic analysis (TEA). A preliminary 550 MW coal-fired power plant using Illinois #6 bituminous coal was designed with a solid sorbent CO2 capture system using the selected supported amine sorbent to both facilitate the TEA and to create the necessary framework to scale down the design to a 1 MWe equivalent slipstream pilot facility. The preliminary techno-economic analysis showed promising results and potential for improved performance for CO2 capture compared to conventional MEA systems. As a result, a 1 MWe equivalent solid sorbent system was designed, constructed, and then installed at a coal-fired power plant in Alabama. The pilot was designed to capture 90% of the CO2 from the incoming flue gas at 1 MWe net electrical generating equivalent. Testing was not possible at the design conditions due to changes in sorbent handling characteristics at post-regenerator temperatures that were not properly incorporated into the pilot design. Thus, severe pluggage occurred at nominally 60% of the design sorbent circulation rate with heated sorbent, although no handling issues were noted when the system was operated prior to bringing the regenerator to operating temperature. Testing within the constraints of the pilot plant resulted in 90% capture of the incoming CO2 at a flow rate equivalent of 0.2 to 0.25 MWe net electrical generating equivalent. The reduction in equivalent flow rate at 90% capture was primarily the result of sorbent circulation limitations at operating

  18. CO2 Capture by Absorption with Potassium Carbonate

    SciTech Connect

    Gary T. Rochelle; Eric Chen; Babatunde Oyenekan; Andrew Sexton; Jason Davis; Marus Hiilliard; Qing Xu; David Van Wagener; Jorge M. Plaza

    2006-12-31

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. The best solvent and process configuration, matrix with MDEA/PZ, offers 22% and 15% energy savings over the baseline and improved baseline, respectively, with stripping and compression to 10 MPa. The energy requirement for stripping and compression to 10 MPa is about 20% of the power output from a 500 MW power plant with 90% CO{sub 2} removal. The stripper rate model shows that a ''short and fat'' stripper requires 7 to 15% less equivalent work than a ''tall and skinny'' one. The stripper model was validated with data obtained from pilot plant experiments at the University of Texas with 5m K{sup +}/2.5m PZ and 6.4m K{sup +}/1.6m PZ under normal pressure and vacuum conditions using Flexipac AQ Style 20 structured packing. Experiments with oxidative degradation at low gas rates confirm the effects of Cu{sup +2} catalysis; in MEA/PZ solutions more formate and acetate is produced in the presence of Cu{sup +2}. At 150 C, the half life of 30% MEA with 0.4 moles CO{sub 2}/mole amine is about 2 weeks. At 100 C, less than 3% degradation occurred in two weeks. The solubility of potassium sulfate in MEA solution increases significantly with CO{sub 2} loading and decreases with MEA concentration. The base case corrosion rate in 5 M MEA/1,2M PZ is 22 mpy. With 1 wt% heat stable salt, the corrosion rate increases by 50% to 160% in the order: thiosulfate< oxalate

  19. Biomimetic Membrane for CO2 Capture from Flue Gas

    SciTech Connect

    Michael C. Trachtenberg

    2007-05-31

    These Phase III experiments successfully addressed several issues needed to characterize a permeator system for application to a pulverized coal (PC) burning furnace/boiler assuming typical post-combustion cleanup devices in place. We completed key laboratory stage optimization and modeling efforts needed to move towards larger scale testing. The SOPO addressed six areas. Task 1--Post-Combustion Particle Cleanup--The first object was to determine if the Carbozyme permeator performance was likely to be reduced by particles (materials) in the flue gas stream that would either obstruct the mouth of the hollow fibers (HF) or stick to the HF bore wall surface. The second, based on the Acceptance Standards (see below), was to determine whether it would be preferable to clean the inlet gas stream (removing acid gases and particulates) or to develop methods to clean the Carbozyme permeator if performance declined due to HF block. We concluded that condensation of particle and particulate emissions, in the heat exchanger, could result in the formation of very sticky sulfate aerosols with a strong likelihood of obtruding the HF. These must be managed carefully and minimized to near-zero status before entering the permeator inlet stream. More extensive post-combustion cleanup is expected to be a necessary expense, independent of CO{sub 2} capture technology This finding is in agreement with views now emerging in the literature for a variety of CO{sub 2} capture methods. Task 2--Water Condensation--The key goal was to monitor and control temperature distributions within the permeator and between the permeator and its surroundings to determine whether water condensation in the pores or the HF bore would block flow, decreasing performance. A heat transfer fluid and delivery system were developed and employed. The result was near isothermal performance that avoided all instances of flow block. Direct thermocouple measurements provided the basis for developing a heat transfer

  20. Ab initio thermodynamic approach to identify mixed solid sorbents for CO2 capture technology

    DOE PAGESBeta

    Duan, Yuhua

    2015-10-15

    Because the current technologies for capturing CO2 are still too energy intensive, new materials must be developed that can capture CO2 reversibly with acceptable energy costs. At a given CO2 pressure, the turnover temperature (Tt) of the reaction of an individual solid that can capture CO2 is fixed. Such Tt may be outside the operating temperature range (ΔTo) for a practical capture technology. To adjust Tt to fit the practical ΔTo, in this study, three scenarios of mixing schemes are explored by combining thermodynamic database mining with first principles density functional theory and phonon lattice dynamics calculations. Our calculated resultsmore » demonstrate that by mixing different types of solids, it’s possible to shift Tt to the range of practical operating temperature conditions. 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 mixed solids of interest, we were able to identify the mixing ratios of two or more solids to form new sorbent materials for which lower capture energy costs are expected at the desired pressure and temperature conditions.« less

  1. Process for capturing CO2 arising from the calcination of the CaCO3 used in cement manufacture.

    PubMed

    Rodríguez, N; Alonso, M; Grasa, G; Abanades, J Carlos

    2008-09-15

    This paper outlines a new CaCO3 calcination method for producing a stream of CO2 (suitable for permanent geological storage after purification and compression). The process is based on the use of very hot CaO particles (T >1000 degrees C) to transfer heat from a circulating fluidized bed combustor (CFBC) to a calciner (fluidized with CO2 and/or steam). Since the fluidized bed combustor and calciner have separate atmospheres, the CO2 resulting from the decomposition of CaCO3 can be captured, while the CO2 generated in the combustion of the fuel in air is emitted to the atmosphere. We demonstrate that with this system it is possible to reduce the CO2 emissions of a cement plant by around 60%. Furthermore, since the key pieces of equipment are similar to the commercial CFBCs used in power generation plants, it is possible to establish the additional investment required for the system and to estimate the cost per ton of CO2 avoided for this process to be about 19 $/tCO2 avoided. PMID:18853819

  2. CO2 Capture by Absorption with Potassium Carbonate

    SciTech Connect

    Gary T. Rochelle; Andrew Sexton; Jason Davis; Marcus Hilliard; Qing Xu; David Van Wagener; Jorge M. Plaza

    2007-03-31

    The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. The best K{sup +}/PZ solvent, 4.5 m K{sup +}/4.5 m PZ, requires equivalent work of 31.8 kJ/mole CO{sub 2} when used with a double matrix stripper and an intercooled absorber. The oxidative degradation of piperazine or organic acids is reduced significantly by inhibitor A, but the production of ethylenediamine is unaffected. The oxidative degradation of piperazine in 7 m MEA/2 m PZ is catalyzed by Cu{sup ++}. The thermal degradation of MEA becomes significant at 120 C. The solubility of potassium sulfate in MEA/PZ solvents is increased at greater CO{sub 2} loading. The best solvent and process configuration, matrix with MDEA/PZ, offers 22% and 15% energy savings over the baseline and improved baseline, respectively, with stripping and compression to 10 MPa. The energy requirement for stripping and compression to 10 MPa is about 20% of the power output from a 500 MW power plant with 90% CO{sub 2} removal. The stripper rate model shows that a ''short and fat'' stripper requires 7 to 15% less equivalent work than a ''tall and skinny'' one. The stripper model was validated with data obtained from pilot plant experiments at the University of Texas with 5m K{sup +}/2.5m PZ and 6.4m K{sup +}/1.6m PZ under normal pressure and vacuum conditions using Flexipac AQ Style 20 structured packing. Experiments with oxidative degradation at low gas rates confirm the effects of Cu{sup +2} catalysis; in MEA/PZ solutions more formate and acetate is produced in the presence of Cu{sup +2}. At 150 C, the half life of 30% MEA with 0.4 moles CO{sub 2}/mole amine is about 2 weeks. At 100 C, less than 3% degradation occurred in two weeks. The solubility of potassium sulfate in MEA solution increases significantly with CO{sub 2} loading and decreases with MEA concentration. The base case corrosion

  3. Design, synthesis, and evaluation of nonaqueous silylamines for efficient CO2 capture.

    PubMed

    Switzer, Jackson R; Ethier, Amy L; Hart, Emily C; Flack, Kyle M; Rumple, Amber C; Donaldson, Jordan C; Bembry, Ashley T; Scott, Owen M; Biddinger, Elizabeth J; Talreja, Manish; Song, Myoung-Geun; Pollet, Pamela; Eckert, Charles A; Liotta, Charles L

    2014-01-01

    A series of silylated amines have been synthesized for use as reversible ionic liquids in the application of post-combustion carbon capture. We describe a molecular design process aimed at influencing industrially relevant carbon capture properties, such as viscosity, temperature of reversal, and enthalpy of regeneration, while maximizing the overall CO2 -capture capacity. A strong structure-property relationship among the silylamines is demonstrated in which minor structural modifications lead to significant changes in the bulk properties of the reversible ionic liquid formed from reaction with CO2 . PMID:24203891

  4. Hopewell Beneficial CO2 Capture for Production of Fuels, Fertilizer and Energy

    SciTech Connect

    UOP; Honeywell Resins & Chemicals; Honeywell Process Solutions; Aquaflow Bionomics Ltd

    2010-09-30

    For Phase 1 of this project, the Hopewell team developed a detailed design for the Small Scale Pilot-Scale Algal CO2 Sequestration System. This pilot consisted of six (6) x 135 gallon cultivation tanks including systems for CO2 delivery and control, algal cultivation, and algal harvesting. A feed tank supplied Hopewell wastewater to the tanks and a receiver tank collected the effluent from the algal cultivation system. The effect of environmental parameters and nutrient loading on CO2 uptake and sequestration into biomass were determined. Additionally the cost of capturing CO2 from an industrial stack emission at both pilot and full-scale was determined. The engineering estimate evaluated Amine Guard technology for capture of pure CO2 and direct stack gas capture and compression. The study concluded that Amine Guard technology has lower lifecycle cost at commercial scale, although the cost of direct stack gas capture is lower at the pilot scale. Experiments conducted under high concentrations of dissolved CO2 did not demonstrate enhanced algae growth rate. This result suggests that the dissolved CO2 concentration at neutral pH was already above the limiting value. Even though dissolved CO2 did not show a positive effect on biomass growth, controlling its value at a constant set-point during daylight hours can be beneficial in an algae cultivation stage with high algae biomass concentration to maximize the rate of CO2 uptake. The limited enhancement of algal growth by CO2 addition to Hopewell wastewater was due at least in part to the high endogenous CO2 evolution from bacterial degradation of dissolved organic carbon present at high levels in the wastewater. It was found that the high level of bacterial activity was somewhat inhibitory to algal growth in the Hopewell wastewater. The project demonstrated that the Honeywell automation and control system, in combination with the accuracy of the online pH, dissolved O2, dissolved CO2, turbidity, Chlorophyll A and

  5. EFFICIENT THEORETICAL SCREENING OF SOLID SORBENTS FOR CO2 CAPTURE APPLICATIONS

    SciTech Connect

    Duan, Yuhua; Sorescu, Dan C; Luebke, David

    2011-01-01

    Carbon dioxide is a major combustion product of coal, which once released into the air can contribute to global climate change. Current CO2 capture technologies for power generation processes including amine solvents and CaO-based sorbent materials require very energy intensive regeneration steps which result in significantly decreased efficiency. Hence, there is a critical need for new materials that can capture and release CO2 reversibly with acceptable energy costs if CO2 is to be captured and sequestered economically. Inorganic sorbents are one such class of materials which typically capture CO2 through the reversible formation of carbonates. 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 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. For a given solid, the first step is to attempt to extract thermodynamic properties from thermodynamic databases and available literatures. If the thermodynamic properties of the compound of interest are unknown, an ab initio thermodynamic approach is used to calculate them. These properties expressed conveniently as chemical potentials and heat of reactions, either from databases or from calculations, are further used for computing the thermodynamic reaction equilibrium properties of the CO2 absorption/desorption cycle based on the chemical potential and heat of reaction. Only those solid materials for which lower capture energy costs are predicted at the desired process conditions are selected as CO2 sorbent candidates and further considered for experimental validations. Solid sorbents containing

  6. Advanced Amine Solvent Formulations and Process Integration for Near-Term CO2 Capture Success

    SciTech Connect

    Fisher, Kevin S.; Searcy, Katherine; Rochelle, Gary T.; Ziaii, Sepideh; Schubert, Craig

    2007-06-28

    This Phase I SBIR project investigated the economic and technical feasibility of advanced amine scrubbing systems for post-combustion CO2 capture at coal-fired power plants. Numerous combinations of advanced solvent formulations and process configurations were screened for energy requirements, and three cases were selected for detailed analysis: a monoethanolamine (MEA) base case and two “advanced” cases: an MEA/Piperazine (PZ) case, and a methyldiethanolamine (MDEA) / PZ case. The MEA/PZ and MDEA/PZ cases employed an advanced “double matrix” stripper configuration. The basis for calculations was a model plant with a gross capacity of 500 MWe. Results indicated that CO2 capture increased the base cost of electricity from 5 cents/kWh to 10.7 c/kWh for the MEA base case, 10.1 c/kWh for the MEA / PZ double matrix, and 9.7 c/kWh for the MDEA / PZ double matrix. The corresponding cost per metric tonne CO2 avoided was 67.20 $/tonne CO2, 60.19 $/tonne CO2, and 55.05 $/tonne CO2, respectively. Derated capacities, including base plant auxiliary load of 29 MWe, were 339 MWe for the base case, 356 MWe for the MEA/PZ double matrix, and 378 MWe for the MDEA / PZ double matrix. When compared to the base case, systems employing advanced solvent formulations and process configurations were estimated to reduce reboiler steam requirements by 20 to 44%, to reduce derating due to CO2 capture by 13 to 30%, and to reduce the cost of CO2 avoided by 10 to 18%. These results demonstrate the potential for significant improvements in the overall economics of CO2 capture via advanced solvent formulations and process configurations.

  7. Finely tuning MOFs towards high-performance post-combustion CO2 capture materials.

    PubMed

    Wang, Qian; Bai, Junfeng; Lu, Zhiyong; Pan, Yi; You, Xiaozeng

    2016-01-11

    CO2 capture science and technology, particularly for the post-combustion CO2 capture, has become one of very important research fields, due to great concern of global warming. Metal-organic frameworks (MOFs) with a unique feature of structural fine-tunability, unlike the traditional porous solid materials, can provide many and powerful platforms to explore high-performance adsorbents for post-combustion CO2 capture. Until now, several strategies for finely tuning MOF structures have been developed, in which either the larger quadrupole moment and polarizability of CO2 are considered: metal ion change (I), functional groups attachment (II) and functional group insertion (III), vary the electronic nature of the pore surface; or targeting the smaller kinetic diameter of CO2 over N2 is focused on: framework interpenetration (IV), ligand shortening (V) and coordination site shifting (VI) contract the pore size of frameworks to improve their CO2 capture properties. In this review, from the viewpoint of synthetic materials scientists/chemists, we would like to introduce and summarize these strategies based upon recent work published by other groups and ourselves. PMID:26512792

  8. Preparation and characterization of aminated graphite oxide for CO2 capture

    NASA Astrophysics Data System (ADS)

    Zhao, Yunxia; Ding, Huiling; Zhong, Qin

    2012-03-01

    Adsorption with solid sorbents is one of the most promising options for postcombustion carbon dioxide (CO2) capture. In this study, aminated graphite oxide used for CO2 adsorption was synthesized, based on the intercalation reaction of graphite oxide (GO) with amines, including ethylenediamine (EDA), diethylenetriamine (DETA) and triethylene tetramine (TETA). The structural information, surface chemistry and thermal behavior of the adsorbent samples were characterized by X-ray powder diffraction (XRD), infrared spectroscopy (IR), transmission electron microscope (TEM), elemental analysis, particle size analysis, nitrogen adsorption as well as differential thermal and thermogravimetric analysis (DSC-TGA). CO2 capture was investigated by dynamic adsorption experiments with N2sbnd CO2 mixed gases at 30 °C. The three kinds of graphite oxide samples modified by excess EDA, DETA and TETA showed similar adsorption behaviors seen from their breakthrough curves. Among them, the sample aminated by EDA exhibited the highest adsorption capacity with the longest breakthrough time of CO2. Before saturation, its adsorption capacity was up to 53.62 mg CO2/g sample. In addition, graphite oxide samples modified by different amount of EDA (EDA/GO raw ratio 10 wt%, 50 wt% and 100 wt%) were prepared in the ethanol. Their CO2 adsorption performance was investigated. The experimental results demonstrated that graphite oxide with 50 wt% EDA had the largest adsorption capacity 46.55 mg CO2/g sample.

  9. CO2 capture by means of an enzyme-based reactor

    NASA Technical Reports Server (NTRS)

    Cowan, R. M.; Ge, J-J; Qin, Y-J; McGregor, M. L.; Trachtenberg, M. C.

    2003-01-01

    We report a means for efficient and selective extraction of carbon dioxide (CO(2)) at low to medium concentration from mixed gas streams. CO(2) capture was accomplished by use of a novel enzyme-based, facilitated transport contained liquid membrane (EBCLM) reactor. The parametric studies we report explore both structural and operational parameters of this design. The structural parameters include carbonic anhydrase (CA) concentration, buffer concentration and pH, and liquid membrane thickness. The operational parameters are temperature, humidity of the inlet gas stream, and CO(2) concentration in the feed stream. The data show that this system effectively captures CO(2) over the range 400 ppm to at least 100,000 ppm, at or around ambient temperature and pressure. In a single pass across this homogeneous catalyst design, given a feed of 0.1% CO(2), the selectivity of CO(2) versus N(2) is 1,090 : 1 and CO(2) versus O(2) is 790 :1. CO(2) permeance is 4.71 x 10(-8) molm(-2) Pa(-1) sec(-1). The CLM design results in a system that is very stable even in the presence of dry feed and sweep gases.

  10. Towards the rational design of organic/inorganic interface for solid supported CO2 capture

    NASA Astrophysics Data System (ADS)

    He, Feng

    Monoethanolamine (MEA, HO(CH2)2NH2) aqueous solution based CO2 capture is the current technology used to mitigate power plants' green house gas emission. Solid based CO2 capture technique is regarded as a promising alternative, because it is more cost-effective and environmentally friendly than the solution based technique. Recently, solid-supported CO2 capture on MEA modified TiO 2 powders has been demonstrated [1]. It is believed that the main reaction pathway involved in solid-supported amine based CO2 capture is similar to the reaction in the amine solution, where the amine group reacts with CO2 to form carbamate (--NHCOO--). From the previous work on the MEA/TiO2 (110) system [2], it is found that MEA covered rutile TiO2 (110) did not capture CO 2. The main reaction pathway in this system was blocked because the amine group attached to the surface. In order to design a functional system, we proposed two possible mechanisms to free --NH2 from rutile TiO2 (110) surface. In this work, we investigated one of our six candidates, the 3-Amino-1-propanol (3AP, HO(CH2) 3NH2) molecule. The classical reactive force field (ReaxFF) [3] method has been employed to investigate the 3AP/TiO2 (110) system with emphasis on binding configurations and binding energies. We found that the amine group of 3AP did not attach to the rutile TiO2 (110) surface, indicating the CO2 capture capability of the 3AP/TiO 2 (110) system, which was confirmed by our experimental collaborators [4].

  11. An asymmetric tubular ceramic-carbonate dual phase membrane for high temperature CO2 separation.

    PubMed

    Dong, Xueliang; Ortiz Landeros, José; Lin, Y S

    2013-10-25

    For the first time, a tubular asymmetric ceramic-carbonate dual phase membrane was prepared by a centrifugal casting technique and used for high temperature CO2 separation. This membrane shows high CO2 permeation flux and permeance. PMID:24022119

  12. 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

  13. Tailoring open metal sites for selective capture of CO2 in isostructural metalloporphyrin porous organic networks

    NASA Astrophysics Data System (ADS)

    Choi, Hwa Seob; Jeon, Hyung Joon; Choi, Jung Hoon; Lee, Gyu-Heon; Kang, Jeung Ku

    2015-11-01

    Porphyrin-based isostructural porous organic networks have been synthesized by varying the central metal atoms to cobalt, nickel and copper. Their selectivities for CO2 capture over N2 and Ar are found to be enhanced as the heats of adsorption for CO2 are increased in the order of Co, Ni and Cu, while the pore structures are well maintained.Porphyrin-based isostructural porous organic networks have been synthesized by varying the central metal atoms to cobalt, nickel and copper. Their selectivities for CO2 capture over N2 and Ar are found to be enhanced as the heats of adsorption for CO2 are increased in the order of Co, Ni and Cu, while the pore structures are well maintained. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr05696a

  14. Rational design and synthesis of a porous, task-specific polycarbazole for efficient CO2 capture.

    PubMed

    Jin, Tian; Xiong, Yan; Zhu, Xiang; Tian, Ziqi; Tao, Duan-Jian; Hu, Jun; Jiang, De-en; Wang, Hualin; Liu, Honglai; Dai, Sheng

    2016-03-25

    We present a rational design and synthesis of a novel porous pyridine-functionalized polycarbazole for efficient CO2 capture based on the density functional theory calculations. The task-specific polymer, generated through a one-step FeCl3-catalyzed oxidative coupling reaction, exhibits a superior CO2 uptake at 1.0 bar and 273 K (5.57 mmol g(-1)). PMID:26864392

  15. Optimal synthesis of a pressure swing adsorption process for CO2 capture

    SciTech Connect

    Agarwal, A.; Biegler, L.; Zitney, S.

    2008-01-01

    The emission of carbon dioxide from cement industry and power plants that burn fossil fuels is the major cause for the accumulation of CO2 in the atmosphere, which causes long-range environmental problems. One option to mitigate the emission of CO2 is to capture it from the emission sources and store it to the ocean or depleted oil field or use it for enhanced oil recovery. CO2 recovery has been achieved by gas absorption employing solutions of carbonates and alkanolamines. However, this process is energy-intensive for the regeneration of solvent and also faces problems due to corrosion. Recently, the pressure swing adsorption (PSA) process has been considered as an alternative to the absorption process. PSA processes have been widely applied for the removal of CO2 from various feed mixtures, such as CO2 in the steam reformer off gas, landfill gas and natural gas. In all these commercial PSA cycles, the weakly adsorbed component in the mixture is the desired product and enriching the strongly adsorbed CO2 is not a concern. On the other hand, for the capture of CO2 for sequestration, it is necessary to concentrate the CO2 to a high purity to reduce the compression and transportation cost. Thus, it is necessary to develop a PSA cycle by which a high-purity product for the strongly adsorbed component with a high recovery is obtained. A multitude of PSA cycles and adsorbents have been developed for producing highly pure heavy component (CO2) from feedstock with low CO2 concentration. Kikkinides et al. suggested a 4-bed 4-step process with activated carbon as the sorbent and could recover 68% of CO2 at 99.997% purity. Chue et al. compared activated carbon and zeolite 13X on a 3-bed 7-step process and concluded that the latter is better than the former for CO2 recovery. However, the CO2 recovery was low in their process due to the lack of a countercurrent step in the chosen cycle. Choi et al. reported more than 70% CO2 recovery at more than 90% purity for a modified 3

  16. Plant-wide dynamic simulation of an IGCC plant with CO2 capture

    SciTech Connect

    Bhattacharyya, D.; Turton, R.; Zitney, S.

    2009-01-01

    To eliminate the harmful effects of greenhouse gases, especially that of CO2, future coalfired power plants need to consider the option for CO2 capture. The loss in efficiency for CO2 capture is less in an Integrated Gasification Combined Cycle (IGCC) plant compared to other conventional coal combustion processes. However, no IGCC plant with CO2 capture currently exists in the world. Therefore, it is important to consider the operability and controllability issues of such a plant before it is commercially built. With this objective in mind, a detailed plant-wide dynamic simulation of an IGCC plant with CO2 capture has been developed. The plant considers a General Electric Energy (GEE)-type downflow radiant-only gasifier followed by a quench section. A two-stage water gas shift (WGS) reaction is considered for conversion of about 96 mol% of CO to CO2. A two-stage acid gas removal (AGR) process based on a physical solvent is simulated for selective capture of H2S and CO2. The clean syngas is sent to a gas turbine (GT) followed by a heat recovery steam generator (HRSG). The steady state results are validated with data from a commercial gasifier. A 5 % ramp increase in the flowrate of coal is introduced to study the system dynamics. To control the conversion of CO at a desired level in the WGS reactors, the steam/CO ratio is manipulated. This strategy is found to be efficient for this operating condition. In the absence of an efficient control strategy in the AGR process, the environmental emissions exceeded the limits by a great extent.

  17. Dehydrated Prussian Blues for CO2 Storage and Separation Applications

    SciTech Connect

    Motkuri, Radha K.; Thallapally, Praveen K.; McGrail, B. Peter; Ghorishi, Behrooz S.

    2010-08-13

    Adsorption isotherms of pure gases present in flue and natural gas including CO2, N2, CH4 and water were studied using prussian blues of chemical formula M3[Co(CN)6]2 (M = Cu, Ni, Mn). These materials adsorbed 8-12 wt % of CO2 at room temperature and 1 bar of pressure with heats of adsorption ranging from 6 to 16 kcal/mol.

  18. Carbonic anhydrase-facilitated CO2 absorption with polyacrylamide buffering bead capture

    SciTech Connect

    Dilmore, Robert; Griffith, Craid; Liu, Zhu; Soong, Yee; Hedges, Sheila W.; Koepsel, Richard; Ataai, M

    2009-07-01

    A novel CO2 separation concept is described wherein the enzyme carbonic anhydrase (CA) is used to increase the overall rate Of CO2 absorption after which hydrated CO2 reacts with regenerable amine-bearing polyacrylamide buffering beads (PABB). Following saturation of the material's immobilized tertiary amines, CA-bearing carrier water is separated and recycled to the absorption stage while CO2-loaded material is thermally regenerated. Process application of this concept would involve operation of two or more columns in parallel with thermal regeneration with low-pressure steam taking place after the capacity of a column of amine-bearing polymeric material was exceeded. PABB CO2- bearing capacity was evaluated by thermogravimetric analysis (TGA) for beads of three acrylamido buffering monomer ingredient concentrations: 0 mol/kg bead, 0.857 mol/kg bead, and 2 mol/kg bead. TGA results demonstrate that CO2- bearing capacity increases with increasing PABB buffering concentration and that up to 78% of the theoretical CO2- bearing capacity was realized in prepared PABB samples (0.857 mol/kg recipe). The highest observed CO2-bearing capacity of PABB was 1.37 mol of CO2 per kg dry bead. TGA was also used to assess the regenerability Of CO2-loaded PABB. Preliminary results suggest that CO2 is partially driven from PABB samples at temperatures as low as 55 degrees C, with complete regeneration occurring at 100 degrees C. Other physical characteristics of PABB are discussed. In addition, the effectiveness of bovine carbonic anhydrase for the catalysis Of CO2 dissolution is evaluated. Potential benefits and drawbacks of the proposed process are discussed. Published by Elsevier Ltd.

  19. Mechanisms of low temperature capture and regeneration of CO2 using diamino protic ionic liquids.

    PubMed

    Simons, Tristan J; Verheyen, Thomas; Izgorodina, Ekaterina I; Vijayaraghavan, R; Young, Scott; Pearson, Andrew K; Pas, Steven J; MacFarlane, Douglas R

    2016-01-14

    Carbon dioxide (CO2) chemical absorption and regeneration was investigated in two diamino carboxylate protic ionic liquids (PILs), dimethylethylenediamine formate (DMEDAH formate) and dimethylpropylenediamine acetate (DMPDAH acetate), using novel calorimetric techniques. The PILs under study have previously been shown to possess a CO2 absorption capacity similar to the industrial standard, 30% aqueous MEA, while requiring much lower temperatures to release the captured CO2. We show that this is in part due to the fact that the PILs exhibit enthalpies of CO2 desorption as low as 40 kJ mol(-1), significantly lower than the 85 kJ mol(-1) required for 30% aqueous MEA. Computational and spectroscopic analyses were used to probe the mechanism of CO2 capture, which was found to proceed via the formation of carbamate moieties on the primary amine of both DMEDAH and DMPDAH. Evidence was also found that weakly acidic counter-ions such as formate and acetate provide, unexpectedly, an additional proton acceptor site in the traditional carbamate mechanism, revealing opportunities to increase CO2 uptake capacity in the future through careful design of the anion and cation used in the PIL capture agent. PMID:26660453

  20. Layered Graphene-Hexagonal BN Nanocomposites: Experimentally Feasible Approach to Charge-Induced Switchable CO2 Capture.

    PubMed

    Tan, Xin; Kou, Liangzhi; Smith, Sean C

    2015-09-01

    Recently, inducing negative charge density on hexagonal boron nitride (h-BN) has been predicted as an effective strategy for controllable, selective, and reversible CO2 capture. However, h-BN is a wide-gap semiconductor and it is not clear how to effectively induce the requisite negative charge density. In this paper, we employ first-principle calculations to propose hybrid h-BN-graphene (hybrid BN/G) nanosheets as an experimentally feasible strategy to induce charge on h-BN for charge-controlled CO2 capture. The results indicate that the charge density is effectively transferred from the graphene layer with high electronic mobility into the h-BN layer on the surface, regardless of the thickness of BN layers, such that CO2 capture/release can be simply controlled by switching on/off the charge states of hybrid BN/G system. In addition, these negatively charged hybrid BN/G are highly selective for separating CO2 from mixtures with CH4 , N2 , and/or H2 . PMID:26073178

  1. Anion-activated, thermoreversible gelation system for the capture, release, and visual monitoring of CO2.

    PubMed

    Zhang, Xin; Lee, Songyi; Liu, Yifan; Lee, Minji; Yin, Jun; Sessler, Jonathan L; Yoon, Juyoung

    2014-01-01

    Carbon dioxide (CO2) is an important green house gas. This is providing an incentive to develop new strategies to detect and capture CO2. Achieving both functions within a single molecular system represents an unmet challenge in terms of molecular design and could translate into enhanced ease of use. Here, we report an anion-activated chemosensor system, NAP-chol 1, that permits dissolved CO2 to be detected in organic media via simple color changes or through ratiometric differences in fluorescence intensity. NAP-chol 1 also acts as a super gelator for DMSO. The resulting gel is transformed into a homogeneous solution upon exposure to fluoride anions. Bubbling with CO2 regenerates the gel. Subsequent flushing with N2 or heating serves to release the CO2 and reform the sol form. This series of transformations is reversible and can be followed by easy-to-discern color changes. Thus, NAP-chol 1 allows for the capture and release of CO2 gas while acting as a three mode sensing system. In particular, it permits CO2 to be detected through reversible sol-gel transitions, simple changes in color, or ratiometric monitoring of the differences in the fluorescence features. PMID:24699626

  2. Progress in Adsorption-Based CO2 Capture by Metal-Organic Frameworks

    SciTech Connect

    Liu, Jian; Thallapally, Praveen K.; McGrail, B. Peter; Brown, Daryl R.; Liu, Jun

    2012-01-01

    Metal-organic frameworks (MOFs) have recently attracted intense research interest because of their permanent porous structures, large surface areas, and potential applications as novel adsorbents. The recent progress in adsorption-based CO2 capture by MOFs is reviewed and summarized in this paper. CO2 adsorption in MOFs has been divided into two sections, adsorption at high pressures and selective adsorption at approximate atmospheric pressures. Keys to CO2 adsorption in MOFs at high pressures and low pressures are summarized to be pore volumes of MOFs, and heats of adsorption, respectively. Many MOFs have high CO2 selectivities over N2 and CH4. Water effects on CO2 adsorption in MOFs are presented and compared with benchmark zeolites. In addition, strategies appeared in the literature to enhance CO2 adsorption capacities and/or selectivities in MOFs have been summarized into three main categories, catenation and interpenetration, chemical bonding enhancement, and electrostatic force involvement. Besides the advantages, two main challenges for using MOFs in CO2 capture, the cost of synthesis and the stability toward water vapor, have been analyzed and possible solutions and path-forward have been proposed to address the two challenges as well.

  3. Anion-activated, thermoreversible gelation system for the capture, release, and visual monitoring of CO2

    NASA Astrophysics Data System (ADS)

    Zhang, Xin; Lee, Songyi; Liu, Yifan; Lee, Minji; Yin, Jun; Sessler, Jonathan L.; Yoon, Juyoung

    2014-04-01

    Carbon dioxide (CO2) is an important green house gas. This is providing an incentive to develop new strategies to detect and capture CO2. Achieving both functions within a single molecular system represents an unmet challenge in terms of molecular design and could translate into enhanced ease of use. Here, we report an anion-activated chemosensor system, NAP-chol 1, that permits dissolved CO2 to be detected in organic media via simple color changes or through ratiometric differences in fluorescence intensity. NAP-chol 1 also acts as a super gelator for DMSO. The resulting gel is transformed into a homogeneous solution upon exposure to fluoride anions. Bubbling with CO2 regenerates the gel. Subsequent flushing with N2 or heating serves to release the CO2 and reform the sol form. This series of transformations is reversible and can be followed by easy-to-discern color changes. Thus, NAP-chol 1 allows for the capture and release of CO2 gas while acting as a three mode sensing system. In particular, it permits CO2 to be detected through reversible sol-gel transitions, simple changes in color, or ratiometric monitoring of the differences in the fluorescence features.

  4. Anion-activated, thermoreversible gelation system for the capture, release, and visual monitoring of CO2

    PubMed Central

    Zhang, Xin; Lee, Songyi; Liu, Yifan; Lee, Minji; Yin, Jun; Sessler, Jonathan L.; Yoon, Juyoung

    2014-01-01

    Carbon dioxide (CO2) is an important green house gas. This is providing an incentive to develop new strategies to detect and capture CO2. Achieving both functions within a single molecular system represents an unmet challenge in terms of molecular design and could translate into enhanced ease of use. Here, we report an anion-activated chemosensor system, NAP-chol 1, that permits dissolved CO2 to be detected in organic media via simple color changes or through ratiometric differences in fluorescence intensity. NAP-chol 1 also acts as a super gelator for DMSO. The resulting gel is transformed into a homogeneous solution upon exposure to fluoride anions. Bubbling with CO2 regenerates the gel. Subsequent flushing with N2 or heating serves to release the CO2 and reform the sol form. This series of transformations is reversible and can be followed by easy-to-discern color changes. Thus, NAP-chol 1 allows for the capture and release of CO2 gas while acting as a three mode sensing system. In particular, it permits CO2 to be detected through reversible sol-gel transitions, simple changes in color, or ratiometric monitoring of the differences in the fluorescence features. PMID:24699626

  5. Human health risk assessment of nitrosamines and nitramines for potential application in CO2 capture.

    PubMed

    Ravnum, S; Rundén-Pran, E; Fjellsbø, L M; Dusinska, M

    2014-07-01

    Emission and accumulation of carbon dioxide (CO2) in the atmosphere exert an environmental and climate change challenge. An attempt to deal with this challenge is made at Mongstad by application of amines for CO2 capture and storage (CO2 capture Mongstad (CCM) project). As part of the CO2 capture process, nitrosamines and nitramines may be emitted. Toxicological testing of nitrosamines and nitramines indicate a genotoxic potential of these substances. Here we present a risk characterization and assessment for five nitrosamines (N-Nitrosodi-methylamine (NDMA) N-Nitrosodi-ethylamine (NDEA), N-Nitroso-morpholine (NNM), N-Nitroso-piperidine (NPIP), and Dinitroso-piperazine (DNP)) and two nitramines (N-Methyl-nitramine (NTMA), Dimethyl-nitramine (NDTMA)), which are potentially emitted from the CO2 capture plant (CCP). Human health risk assessment of genotoxic non-threshold substances is a heavily debated topic, and no consensus methodology exists internationally. Extrapolation modeling from high-dose animal exposures to low-dose human exposures can be crucial for the final risk calculation. In the work presented here, different extrapolation models are discussed, and suggestions on applications are given. Then, preferred methods for calculating derived minimal effect level (DMEL) are presented with the selected nitrosamines and nitramines. PMID:24747397

  6. Effects of flue gas compositions on nitrosamine and nitramine formation in postcombustion CO2 capture systems.

    PubMed

    Dai, Ning; Mitch, William A

    2014-07-01

    Amine-based technologies are emerging as the prime contender for postcombustion CO2 capture. However, concerns have arisen over the health impacts of amine-based CO2 capture associated with the release of nitrosamines and nitramines, which are byproducts from the reactions between flue gas NOx and solvent amines. In this study, flue gas compositions were systematically varied to evaluate their effects on the formation of nitrosamines and nitramines in a lab-scale CO2 capture reactor with morpholine as a model solvent amine. The accumulation of N-nitrosomorpholine in both the absorber and washwater increased linearly with both NO and NO2 for concentrations up to ∼20 ppmv. These correlations could be extrapolated to estimate N-nitrosomorpholine accumulation at extremely low NOx levels (0.3 ppmv NO2 and 1.5 ppmv NO). NO played a particularly important role in driving N-nitrosomorpholine formation in the washwater, likely following partial oxidation to NO2 by O2. The accumulation of N-nitromorpholine in both the absorber and washwater positively correlated with flue gas NO2 concentration, but not with NO concentration. Both N-nitrosomorpholine and N-nitromorpholine accumulated fastest in the absence of CO2. Flue gas humidity did not affect nitrosamine accumulation in either the absorber or the washwater unit. These results provide a basis for estimating the effects of flue gas composition on nitrosamine and nitramine accumulation in postcombustion CO2 capture systems. PMID:24918477

  7. Chemical vapor deposition on chabazite (CHA) zeolite membranes for effective post-combustion CO2 capture.

    PubMed

    Kim, Eunjoo; Lee, Taehee; Kim, Hyungmin; Jung, Won-Jin; Han, Doug-Young; Baik, Hionsuck; Choi, Nakwon; Choi, Jungkyu

    2014-12-16

    Chabazite (CHA) zeolites with a pore size of 0.37 × 0.42 nm(2) are expected to separate CO2 (0.33 nm) from larger N2 (0.364 nm) in postcombustion flue gases by recognizing their minute size differences. Furthermore, the hydrophobic siliceous constituent in CHA membranes can allow for maintaining the CO2/N2 separation performance in the presence of H2O in contrast with the CO2 affinity-based membranes. In an attempt to increase the molecular sieving ability, the pore mouth size of all silica CHA (Si-CHA) particles was reduced via the chemical vapor deposition (CVD) of a silica precursor (tetraethyl orthosilicate). Accordingly, an increase of the CVD treatment duration decreased the penetration rate of CO2 into the CVD-treated Si-CHA particles. Furthermore, the CVD process was applied to siliceous CHA membranes in order to improve their CO2/N2 separation performance. Compared to the intact CHA membranes, the CO2/N2 maximum separation factor (max SF) for CVD-treated CHA membranes was increased by ∼ 2 fold under dry conditions. More desirably, the CO2/N2 max SF was increased by ∼ 3 fold under wet conditions at ∼ 50 °C, a representative temperature of the flue gas stream. In fact, the presence of H2O in the feed disfavored the permeation of N2 more than that of CO2 through CVD-modified CHA membranes and thus, contributed to the increased CO2/N2 separation factor. PMID:25479409

  8. Imidazole tailored deep eutectic solvents for CO2 capture enhanced by hydrogen bonds.

    PubMed

    Cao, Lingdi; Huang, Junhua; Zhang, Xiangping; Zhang, Suojiang; Gao, Jubao; Zeng, Shaojuan

    2015-11-01

    Deep eutectic solvents (DESs) have emerged as promising alternative candidates for CO2 capture in recent years. In this work, several novel DESs were firstly prepared to enhance CO2 absorption. Structural and physical properties of DESs were investigated, as well as their absorption performance of CO2. A distinct depression in the melting point up to 80 K of DESs was observed compared with that of BMIMCl. The observed red shifts of the C2H group in an imidazolium ring and its chemical shifts downfield in NMR spectra are indicative of a hydrogen bond interaction between BMIMCl and MEA. In particular, CO2 uptake in MEA : ILs (4 : 1) at room temperature and atmospheric pressure is up to 21.4 wt%, which is higher than that of 30 wt% MEA (13%). A hydrogen bond related mechanism was proposed in which ILs act as a medium to improve CO2 uptake through hydrogen bonds. Finally, the firstly reported overall heat of CO2 absorption is slightly higher than that of 30 wt% MEA, implying that the hydrogen bonds of DESs contribute to the overall heat of CO2 absorption. This study reveals that the heat of CO2 absorption can be tailored by the proper molar ratio of MEA and ILs. PMID:26435384

  9. Energy requirements for CO2 capture from ambient air (DAC) competitive with capture from flue-gas (PCC)

    NASA Astrophysics Data System (ADS)

    Meinrenken, Christoph

    2015-03-01

    Capture of CO2, whether from a flue gas source (PCC) or from distributed sources via ambient air (DAC), is a key enabling technology to provide carbon for sustainable synthetic energy carriers such as solar fuels. Based on thermodynamic minimum considerations, DAC is often expected to require about 3 times more energy (per ton CO2 captured) than PCC because CO2 in ambient air is more dilute. Here, we calculate the energy required for a humidity swing-based DAC installation that uses an anionic exchange resin as sorbent. The calculation uses recently measured equilibrium CO2 loadings of the sorbent as function of partial CO2 pressure, temperature, and humidity. We calculate the installation's electricity consumption to be about 45 kJ per mole of pure CO2 at 1 bar (scenario-dependent). Furthermore, we estimate the amount of heat provided by ambient air and thus provide context of the overall energy and entropy balance and thermodynamic minimum views. The electricity consumption is competitive with typical parasitic loads of PCC-equipped coal-fired power plants (40-50 kJ per mole at same pressure) and significantly lower than predicted for other DAC installations such as Na(OH) sorbent-based systems. Our analyses elucidate why DAC is not always more energy-intensive that PCC, thus alleviating often cited concerns of significant cost impediments. Financial support by ABB for research presented herein is gratefully acknowledged.

  10. Cycle development and design for CO2 capture from flue gas by vacuum swing adsorption.

    PubMed

    Zhang, Jun; Webley, Paul A

    2008-01-15

    CO2 capture and storage is an important component in the development of clean power generation processes. One CO2 capture technology is gas-phase adsorption, specifically pressure (or vacuum) swing adsorption. The complexity of these processes makes evaluation and assessment of new adsorbents difficult and time-consuming. In this study, we have developed a simple model specifically targeted at CO2 capture by pressure swing adsorption and validated our model by comparison with data from a fully instrumented pilot-scale pressure swing adsorption process. The model captures nonisothermal effects as well as nonlinear adsorption and nitrogen coadsorption. Using the model and our apparatus, we have designed and studied a large number of cycles for CO2 capture. We demonstrate that by careful management of adsorption fronts and assembly of cycles based on understanding of the roles of individual steps, we are able to quickly assess the effect of adsorbents and process parameters on capture performance and identify optimal operating regimes and cycles. We recommend this approach in contrast to exhaustive parametric studies which tend to depend on specifics of the chosen cycle and adsorbent. We show that appropriate combinations of process steps can yield excellent process performance and demonstrate how the pressure drop, and heat loss, etc. affect process performance through their effect on adsorption fronts and profiles. Finally, cyclic temperature profiles along the adsorption column can be readily used to infer concentration profiles-this has proved to be a very useful tool in cyclic function definition. Our research reveals excellent promise for the application of pressure/vacuum swing adsorption technology in the arena of CO2 capture from flue gases. PMID:18284163

  11. High-performance multilayer composite membranes with mussel-inspired polydopamine as a versatile molecular bridge for CO2 separation.

    PubMed

    Li, Panyuan; Wang, Zhi; Li, Wen; Liu, Yanni; Wang, Jixiao; Wang, Shichang

    2015-07-22

    It is desirable to develop high-performance composite membranes for efficient CO2 separation in CO2 capture process. Introduction of a highly permeable polydimethylsiloxane (PDMS) intermediate layer between a selective layer and a porous support has been considered as a simple but efficient way to enhance gas permeance while maintaining high gas selectivity, because the introduced intermediate layer could benefit the formation of an ultrathin defect-free selective layer owing to the circumvention of pore penetration phenomenon. However, the selection of selective layer materials is unfavorably restricted because of the low surface energy of PDMS. Various highly hydrophilic membrane materials such as amino group-rich polyvinylamine (PVAm), a representative facilitated transport membrane material for CO2 separation, could not be facilely coated over the surface of the hydrophobic PDMS intermediate layer uniformly. Inspired by the hydrophilic nature and strong adhesive ability of polydopamine (PDA), PDA was therefore selected as a versatile molecular bridge between hydrophobic PDMS and hydrophilic PVAm. The PDA coating endows a highly compatible interface between both components with a large surface energy difference via multiple-site cooperative interactions. The resulting multilayer composite membrane with a thin facilitated transport PVAm selective layer exhibits a notably enhanced CO2 permeance (1887 GPU) combined with a slightly improved CO2/N2 selectivity (83), as well as superior structural stability. Similarly, the multilayer composite membrane with a hydrophilic CO2-philic Pebax 1657 selective layer was also developed for enhanced CO2 separation performance. PMID:26121208

  12. Folding of graphene slit like pore walls—a simple method of improving CO2 separation from mixtures with CH4 or N2

    NASA Astrophysics Data System (ADS)

    Furmaniak, Sylwester; Terzyk, Artur P.; Gauden, Piotr A.; Kowalczyk, Piotr; Harris, Peter J. F.

    2014-12-01

    We report for the first time a detailed procedure for creating a simulation model of energetically stable, folded graphene-like pores and simulation results of CO2/CH4 and CO2/N2 separation using these structures. We show that folding of graphene structures is a very promising method to improve the separation of CO2 from mixtures with CH4 and N2. The separation properties of the analysed materials are compared with carbon nanotubes having similar diameters or S/V ratio. The presented results have potential importance in the field of CO2 capture and sequestration.

  13. Folding of graphene slit like pore walls--a simple method of improving CO2 separation from mixtures with CH4 or N2.

    PubMed

    Furmaniak, Sylwester; Terzyk, Artur P; Gauden, Piotr A; Kowalczyk, Piotr; Harris, Peter J F

    2014-12-01

    We report for the first time a detailed procedure for creating a simulation model of energetically stable, folded graphene-like pores and simulation results of CO2/CH4 and CO2/N2 separation using these structures. We show that folding of graphene structures is a very promising method to improve the separation of CO2 from mixtures with CH4 and N2. The separation properties of the analysed materials are compared with carbon nanotubes having similar diameters or S/V ratio. The presented results have potential importance in the field of CO2 capture and sequestration. PMID:25352074

  14. CO2 capture in amine solutions from ab initio molecular dynamics

    NASA Astrophysics Data System (ADS)

    Ma, Changru; Pietrucci, Fabio; Andreoni, Wanda

    2014-03-01

    The most mature technology for post-combustion CO2 capture exploits a cyclic process, in which CO2 is selectively and reversibly absorbed in an amine solution, typically monoethanolamine(MEA) at 30%wt concentration. Empirical efforts are ongoing worldwide to reduce the high energy penalty for amine regeneration and to increase the absorption rate. Computer simulations can help by providing new insights and the missing quantitative information. Using extensive large-scale Car-Parrinello molecular dynamics simulations, aided by accelerated sampling techniques, we have characterized the reactions leading to CO2 capture in MEA 30%wt solutions via the formation of the carbamate, and the subsequent CO2 release. Deprotonation and CO2 release turn out to be competitive for an intermediate zwitterion (free-energy barrier ~10kcal/mol), with sizable entropic contribution, whereas CO2 release from the carbamate has a much higher barrier (~50kcal/mol), mainly enthalpic and rather independent of temperature. An unprecedented characterization of structural and vibrational properties of the solution allows us to interpret recent experimental results. More results on other amines, allow us to rationalize their still unexplained better performance relative to MEA. We acknowledge PRACE for awarding us access to resource Juqueen based in Germany at Juelich.

  15. Amine-Impregnated Mesoporous Silica Nanotube as an Emerging Nanocomposite for CO2 Capture.

    PubMed

    Niu, Mengya; Yang, Huaming; Zhang, Xiangchao; Wang, Yutang; Tang, Aidong

    2016-07-13

    Pristine halloysite nanotubes (HNTs) were pretreated to produce mesoporous silica nanotubes (MSiNTs), which was further impregnated with polyethenimine (PEI) to prepare an emerging nanocomposite MSiNTs/PEI (MP) for CO2 capture. Thermogravimetric analysis (TGA) was employed to analyze the influences of PEI loading amount and adsorption temperature on CO2 adsorption capacity of the nanocomposite. The Brunauer-Emmett-Teller (BET) surface area (SBET) of MSiNTs was six times higher than that of HNTs, and the corresponding pore volume was more than two times higher than that of HNTs. The well dispersion of PEI within the nanotubes of MSiNTs benefits more CO2 gas adsorption, and the adsorption capacity of the nanocomposite could reach 2.75 mmol/g at 85 °C for 2 h. The CO2 adsorption on the nanocomposite was demonstrated to occur via a two-stage process: initially, a sharp linear weight increase at the beginning, and then a relatively slow adsorption step. The adsorption capacity could reach as high as 70% within 2 min. Also, the nanocomposite exhibited good stability on CO2 adsorption/desorption performance, indicating that the as-prepared emerging nanocomposite show an interesting application potential in the field of CO2 capture. PMID:27315143

  16. Integration of CO2 capture and mineral carbonation by using recyclable ammonium salts.

    PubMed

    Wang, Xiaolong; Maroto-Valer, M Mercedes

    2011-09-19

    A new approach to capture and store CO(2) by mineral carbonation using recyclable ammonium salts was studied. This process integrates CO(2) capture with mineral carbonation by employing NH(3), NH(4)HSO(4), and NH(4)HCO(3) in the capture, mineral dissolution, and carbonation steps, respectively. NH(4)HSO(4) and NH(3) can then be regenerated by thermal decomposition of (NH(4))(2)SO(4). The use of NH(4)HCO(3) as the source of CO(2) can avoid desorption and compression of CO(2). The mass ratio of Mg/NH(4)HCO(3)/NH(3) is the key factor controlling carbonation and the optimum ratio of 1:4:2 gives a conversion of Mg ions to hydromagnesite of 95.5%. Thermogravimetric analysis studies indicated that the regeneration efficiency of NH(4)HSO(4) and NH(3) in this process is 95%. The mass balance of the process shows that about 2.63 tonnes of serpentine, 0.12 tonnes of NH(4)HSO(4), 7.48 tonnes of NH(4)HCO(3), and 0.04 tonnes of NH(3) are required to sequester 1 tonne of CO(2) as hydromagnesite. PMID:21732542

  17. A Biomimetic Three-Dimensional Gas Exchange Unit for CO 2 Capture

    NASA Astrophysics Data System (ADS)

    Nguyen, Du Thai

    For the capture of CO2 from mixed gas streams, materials for increased gas exchange are necessary. Efficient gas exchange systems already exist in the form of vascularized lung-tissue. Herein we report a fabrication technique for the synthesis of three-dimensional microvascular gas exchange units capable of removing CO2 from flowing gas created using the recently reported Vaporization of a Sacrificial Component (VaSC) technique. We demonstrate the spatiotemporal pattern of CO2 reactivity in the microvascular gas exchange unit using colorimetric, pH sensitive dyes. Control over three-dimensional placement of channels is shown to increase capture efficiencies. A computational finite element model validates and explains the experimental observations.

  18. Preparation and characterization of amine-functionalized sugarcane bagasse for CO2 capture.

    PubMed

    Luo, Shihe; Chen, Siyu; Chen, Shuixia; Zhuang, Linzhou; Ma, Nianfang; Xu, Teng; Li, Qihan; Hou, Xunan

    2016-03-01

    A low-cost solid amine adsorbent for CO2 capture was prepared by using sugarcane bagasse (SB), a dominant agro-industrial residue in the sugar and alcohol industry as raw materials. In this preparation process, acrylamide was grafted on SB, and the grafted fiber was then aminated with different type of amine reagents to introduce primary and secondary amine groups onto the surface of SB fibers. The graft and amination conditions were optimized. The prepared solid amine adsorbent showed remarkable CO2 adsorption capacity and the adsorption capacity of the solid amine adsorbent could reach 5.01 mmol CO2/g at room temperature. The comparison of adsorption capacities of amine fibers aminated with various amination agents demonstrated that fibers aminated with triethylenetetramine would obtain higher adsorption capacities and higher amine efficiency. These adsorbents also showed good regeneration performance, the regenerated adsorbent could maintain almost the same adsorption capacity for CO2 after 10 recycles. PMID:26706226

  19. The effect of pyridine modification of Ni-DOBDC on CO2 capture under humid conditions.

    PubMed

    Bae, Youn-Sang; Liu, Jian; Wilmer, Christopher E; Sun, Hahnbi; Dickey, Allison N; Kim, Min Bum; Benin, Annabelle I; Willis, Richard R; Barpaga, Dushyant; LeVan, M Douglas; Snurr, Randall Q

    2014-03-28

    The metal-organic framework Ni-DOBDC was modified with pyridine molecules to make the normally hydrophilic internal surface more hydrophobic. Experiments and molecular simulations show that the pyridine modification reduces H2O adsorption while retaining substantial CO2 capacity under the conditions of interest for carbon capture from flue gas. PMID:24527490

  20. Efficient Theoretical Screening of Solid Sorbents for CO2 Capture Applications*

    SciTech Connect

    Duan, Yuhua; Luebke, David; Pennline, Henry

    2012-03-31

    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 ab initio thermodynamic technique has the advantage of allowing identification of thermodynamic properties of CO2 capture reactions without any experimental input beyond crystallographic structural information of the solid phases involved. For a given solid, the first step is to attempt to extract thermodynamic properties from thermodynamic databases and the available literatures. If the thermodynamic properties of the compound of interest are unknown, an ab initio thermodynamic approach is used to calculate them. These properties expressed conveniently as chemical potentials and heat of reactions, which obtained either from databases or from calculations, are further used for computing the thermodynamic reaction equilibrium properties of the CO2 absorption/desorption cycles. Only those solid materials for which lower capture energy costs are predicted at the desired process conditions are selected as CO2 sorbent candidates and are further considered for experimental validations. Solid sorbents containing alkali and alkaline earth metals have been reported in several previous studies to be good candidates for CO2 sorbent applications due to their high CO2 absorption capacity at moderate working temperatures. In addition to introducing our computational screening procedure, in this presentation we will summarize our results for solid systems composed by alkali and alkaline earth metal oxides, hydroxides, and carbon- ates/bicarbonates to validate our methodology. Additionally, applications of our computational method to mixed solid systems of Li2O with SiO2/ZrO2 with different mixing ratios, our preliminary results showed that increasing the Li2O/SiO2 ratio in

  1. Composite Membranes for CO2 Capture: High Performance Metal Organic Frameworks/Polymer Composite Membranes for Carbon Dioxide Capture

    SciTech Connect

    2010-07-01

    IMPACCT Project: A team of six faculty members at Georgia Tech are developing an enhanced membrane by fitting metal organic frameworks, compounds that show great promise for improved carbon capture, into hollow fiber membranes. This new material would be highly efficient at removing CO2 from the flue gas produced at coal-fired power plants. The team is analyzing thousands of metal organic frameworks to identify those that are most suitable for carbon capture based both on their ability to allow coal exhaust to pass easily through them and their ability to select CO2 from that exhaust for capture and storage. The most suitable frameworks would be inserted into the walls of the hollow fiber membranes, making the technology readily scalable due to their high surface area. This composite membrane would be highly stable, withstanding the harsh gas environment found in coal exhaust.

  2. Synthesis of DNL-6 with a high concentration of Si (4 Al) environments and its application in CO(2) separation.

    PubMed

    Su, Xiong; Tian, Peng; Fan, Dong; Xia, Qinghua; Yang, Yue; Xu, Shutao; Zhang, Lin; Zhang, Ying; Wang, Dehua; Liu, Zhongmin

    2013-05-01

    The synthesis of DNL-6 with a high concentration of Si (4 Al) environments [Si/(Si+Al+P)=0.182 mol, denoted as M-DNL-6] is demonstrated. This represents the highest reported concentration of such environments in silicoaluminophosphate (SAPO) molecular sieves. Adsorption studies show that the high Si (4 Al) content in M-DNL-6, with an increased number of Brønsted acid sites in the framework, greatly promotes the adsorption of CO(2). M-DNL-6 exhibits a large CO(2) uptake capacity of up to 6.18 mmol g(-1) at 273 K and 101 kPa, and demonstrates high ratios of CO(2)/CH(4) and CO(2)/N(2) separation. From breakthrough and cycling experiments, M-DNL-6 demonstrates the ability to completely separate CO(2) from CH(4) or N(2) with a dynamic capacity of approximately 8.0 wt % before breakthrough. Importantly, the adsorbed CO(2) is easily released from the adsorbent through a simple gas purging operation at room temperature to regain 95 % of the original adsorption capacity. These results suggest that M-DNL-6 can be used as a potential adsorbent for CO(2) capture in pressure swing adsorption processes. PMID:23606439

  3. CO2 post-combustion capture in coal-fired power plants integrated with solar systems

    NASA Astrophysics Data System (ADS)

    Carapellucci, R.; Giordano, L.; Vaccarelli, M.

    2015-11-01

    The majority of the World's primary energy consumption is still based on fossil fuels, representing the largest source of global CO2 emissions. According to the Intergovernmental Panel on Climate Change (IPCC), such emissions must be significantly reduced in order to avoid the dramatic consequences of global warming. A potential way to achieve this ambitious goal is represented by the implementation of CCS (Carbon Capture and Storage) technologies. However, the significant amount of energy required by the CCS systems still represents one the major barriers for their deployment. Focusing on post-combustion capture based on amine absorption, several interesting options have been investigated to compensate the energy losses due to solvent regeneration, also using renewable energy sources. One of the most promising is based on the use of concentrating solar power (CSP), providing a part of the energy requirement of the capture island. In this study the integration of a CSP system into a coal-fired power plant with CO2 postcombustion capture is investigated. Basically, a CSP system is used to support the heat requirement for amine regeneration, by producing saturated steam at low temperature. This allows to reduce or even eliminate the conventional steam extraction from the main power plant, affecting positively net power production and efficiency. The energy analysis of the whole system is carried out using the GateCycle software to simulate the coal-fired power plant and ChemCad platform for the CO2 capture process based on amine absorption.

  4. Transient studies of an Integrated Gasification Combined Cycle (IGCC) plant with CO2 capture

    SciTech Connect

    Bhattacharyya, D.; Turton, R.; Zitney, S.

    2010-01-01

    Next-generation coal-fired power plants need to consider the option for CO2 capture as stringent governmental mandates are expected to be issued in near future. Integrated gasification combined cycle (IGCC) plants are more efficient than the conventional coal combustion processes when the option for CO2 capture is considered. However, no IGCC plant with CO2 capture currently exists in the world. Therefore, it is important to consider the operability and controllability issues of such a plant before it is commercially built. To facilitate this objective, a detailed plant-wide dynamic simulation of an IGCC plant with 90% CO2 capture has been developed in Aspen Plus Dynamics{reg_sign}. The plant considers a General Electric Energy (GEE)-type downflow radiant-only gasifier followed by a quench section. A two-stage water gas shift (WGS) reaction is considered for conversion of CO to CO2. A two-stage acid gas removal (AGR) process based on a physical solvent is simulated for selective capture of H2S and CO2. Compression of the captured CO2 for sequestration, an oxy-Claus process for removal of H2S and NH3, black water treatment, and the sour water treatment are also modeled. The tail gas from the Claus unit is recycled to the SELEXOL unit. The clean syngas from the AGR process is sent to a gas turbine followed by a heat recovery steam generator. This turbine is modeled as per published data in the literature. Diluent N2 is used from the elevated-pressure ASU for reducing the NOx formation. The heat recovery steam generator (HRSG) is modeled by considering generation of high-pressure, intermediate-pressure, and low-pressure steam. All of the vessels, reactors, heat exchangers, and the columns have been sized. The basic IGCC process control structure has been synthesized by standard guidelines and existing practices. The steady state results are validated with data from a commercial gasifier. In the future grid-connected system, the plant should satisfy the environmental

  5. CO2 capture from simulated fuel gas mixtures using semiclathrate hydrates formed by quaternary ammonium salts.

    PubMed

    Park, Sungwon; Lee, Seungmin; Lee, Youngjun; Seo, Yongwon

    2013-07-01

    In order to investigate the feasibility of semiclathrate hydrate-based precombustion CO2 capture, thermodynamic, kinetic, and spectroscopic studies were undertaken on the semiclathrate hydrates formed from a fuel gas mixture of H2 (60%) + CO2 (40%) in the presence of quaternary ammonium salts (QASs) such as tetra-n-butylammonium bromide (TBAB) and fluoride (TBAF). The inclusion of QASs demonstrated significantly stabilized hydrate dissociation conditions. This effect was greater for TBAF than TBAB. However, due to the presence of dodecahedral cages that are partially filled with water molecules, TBAF showed a relatively lower gas uptake than TBAB. From the stability condition measurements and compositional analyses, it was found that with only one step of semiclathrate hydrate formation with the fuel gas mixture from the IGCC plants, 95% CO2 can be enriched in the semiclathrate hydrate phase at room temperature. The enclathration of both CO2 and H2 in the cages of the QAS semiclathrate hydrates and the structural transition that results from the inclusion of QASs were confirmed through Raman and (1)H NMR measurements. The experimental results obtained in this study provide the physicochemical background required for understanding selective partitioning and distributions of guest gases in the QAS semiclathrate hydrates and for investigating the feasibility of a semiclathrate hydrate-based precombustion CO2 capture process. PMID:23718261

  6. High temperature CO2 capture using calcium oxide sorbent in a fixed-bed reactor.

    PubMed

    Dou, Binlin; Song, Yongchen; Liu, Yingguang; Feng, Cong

    2010-11-15

    The gas-solid reaction and breakthrough curve of CO(2) capture using calcium oxide sorbent at high temperature in a fixed-bed reactor are of great importance, and being influenced by a number of factors makes the characterization and prediction of these a difficult problem. In this study, the operating parameters on reaction between solid sorbent and CO(2) gas at high temperature were investigated. The results of the breakthrough curves showed that calcium oxide sorbent in the fixed-bed reactor was capable of reducing the CO(2) level to near zero level with the steam of 10 vol%, and the sorbent in CaO mixed with MgO of 40 wt% had extremely low capacity for CO(2) capture at 550°C. Calcium oxide sorbent after reaction can be easily regenerated at 900°C by pure N(2) flow. The experimental data were analyzed by shrinking core model, and the results showed reaction rates of both fresh and regeneration sorbents with CO(2) were controlled by a combination of the surface chemical reaction and diffusion of product layer. PMID:20724072

  7. A Parametric Study for Regenerative Ammonia-Based Scrubbing for the Capture of CO2

    SciTech Connect

    Resnik, K.P.; Garber, W.; Hreda, D.C.; Yeh, J.T.; Pennline, H.W.

    2006-09-01

    A continuous gas and liquid flow, regenerative scrubbing process for CO2 capture is currently being demonstrated at the bench-scale level. An aqueous ammonia-based solution captures CO2 from simulated flue gas in an absorber and releases a nearly pure stream of CO2 in the regenerator. After the regeneration, the solution of ammonium compounds is recycled to the absorber. The design of the continuous flow unit was based on earlier exploratory results from a semi-batch reactor, where a CO2 and N2 gas mixture flowed through a well-mixed batch of ammonia-based solution. Recently, a series of tests have been conducted on the continuous unit to observe the effect of various parameters on CO2 removal efficiency and regenerator effectiveness within the flow system. The parameters that were studied include absorber temperature, regenerator temperature, initial NH3 concentration, simulated flue gas flow rate, liquid solvent inventory in the flow system, and height of the packed-bed absorber. Results from this current testing campaign conducted in the continuous scrubbing unit as well as test results from a 5-cycle semi-batch reactor will be discussed.

  8. Predicting the ultimate potential of natural gas SOFC power cycles with CO2 capture - Part A: Methodology and reference cases

    NASA Astrophysics Data System (ADS)

    Campanari, Stefano; Mastropasqua, Luca; Gazzani, Matteo; Chiesa, Paolo; Romano, Matteo C.

    2016-08-01

    Driven by the search for the highest theoretical efficiency, in the latest years several studies investigated the integration of high temperature fuel cells in natural gas fired power plants, where fuel cells are integrated with simple or modified Brayton cycles and/or with additional bottoming cycles, and CO2 can be separated via chemical or physical separation, oxy-combustion and cryogenic methods. Focusing on Solid Oxide Fuel Cells (SOFC) and following a comprehensive review and analysis of possible plant configurations, this work investigates their theoretical potential efficiency and proposes two ultra-high efficiency plant configurations based on advanced intermediate-temperature SOFCs integrated with a steam turbine or gas turbine cycle. The SOFC works at atmospheric or pressurized conditions and the resulting power plant exceeds 78% LHV efficiency without CO2 capture (as discussed in part A of the work) and 70% LHV efficiency with substantial CO2 capture (part B). The power plants are simulated at the 100 MW scale with a complete set of realistic assumptions about fuel cell (FC) performance, plant components and auxiliaries, presenting detailed energy and material balances together with a second law analysis.

  9. Predicting the ultimate potential of natural gas SOFC power cycles with CO2 capture - Part A: Methodology and reference cases

    NASA Astrophysics Data System (ADS)

    Campanari, Stefano; Mastropasqua, Luca; Gazzani, Matteo; Chiesa, Paolo; Romano, Matteo C.

    2016-08-01

    Driven by the search for the highest theoretical efficiency, in the latest years several studies investigated the integration of high temperature fuel cells in natural gas fired power plants, where fuel cells are integrated with simple or modified Brayton cycles and/or with additional bottoming cycles, and CO2 can be separated via chemical or physical separation, oxy-combustion and cryogenic methods. Focusing on Solid Oxide Fuel Cells (SOFC) and following a comprehensive review and analysis of possible plant configurations, this work investigates their theoretical potential efficiency and proposes two ultra-high efficiency plant configurations based on advanced intermediate-temperature SOFCs integrated with a steam turbine or gas turbine cycle. The SOFC works at atmospheric or pressurized conditions and the resulting power plant exceeds 78% LHV efficiency without CO2 capture (as discussed in part A of the work) and 70% LHV efficiency with substantial CO2 capture (part B). The power plants are simulated at the 100 MW scale with a complete set of realistic assumptions about fuel cell (FC) performance, plant components and auxiliaries, presenting detailed energy and material balances together with a second law analysis.

  10. Development of a carbonate absorption-based process for post-combustion CO2 capture: The role of biocatalyst to promote CO2 absorption rate

    USGS Publications Warehouse

    Lu, Y.; Ye, X.; Zhang, Z.; Khodayari, A.; Djukadi, T.

    2011-01-01

    An Integrated Vacuum Carbonate Absorption Process (IVCAP) for post-combustion carbon dioxide (CO2) capture is described. IVCAP employs potassium carbonate (PC) as a solvent, uses waste or low quality steam from the power plant for CO2 stripping, and employs a biocatalyst, carbonic anhydrase (CA) enzyme, for promoting the CO2 absorption into PC solution. A series of experiments were performed to evaluate the activity of CA enzyme mixed in PC solutions in a stirred tank reactor system under various temperatures, CA dosages, CO2 loadings, CO2 partial pressures, and the presence of major flue gas contaminants. It was demonstrated that CA enzyme is an effective biocatalyst for CO2 absorption under IVCAP conditions. ?? 2011 Published by Elsevier Ltd.

  11. Molecular template-directed synthesis of microporous polymer networks for highly selective CO2 capture.

    PubMed

    Shi, Yao-Qi; Zhu, Jing; Liu, Xiao-Qin; Geng, Jian-Cheng; Sun, Lin-Bing

    2014-11-26

    Porous polymer networks have great potential in various applications including carbon capture. However, complex monomers and/or expensive catalysts are commonly used for their synthesis, which makes the process complicated, costly, and hard to scale up. Herein, we develop a molecular template strategy to fabricate new porous polymer networks by a simple nucleophilic substitution reaction of two low-cost monomers (i.e., chloromethylbenzene and ethylene diamine). The polymerization reactions can take place under mild conditions in the absence of any catalysts. The resultant materials are interconnected with secondary amines and show well-defined micropores due to the structure-directing role of solvent molecules. These properties make our materials highly efficient for selective CO2 capture, and unusually high CO2/N2 and CO2/CH4 selectivities are obtained. Furthermore, the adsorbents can be completely regenerated under mild conditions. Our materials may provide promising candidates for selective capture of CO2 from mixtures such as flue gas and natural gas. PMID:25401996

  12. highly selective amino acid salt solutions as absorption liquid for CO(2) capture in gas-liquid membrane contactors.

    PubMed

    Simons, Katja; Nijmeijer, Kitty; Mengers, Harro; Brilman, Wim; Wessling, Matthias

    2010-08-23

    The strong anthropogenic increase in the emission of CO(2) and the related environmental impact force the developments towards sustainability and carbon capture and storage (CCS). In the present work, we combine the high product yields and selectivities of CO(2) absorption processes with the advantages of membrane technology in a membrane contactor for the separation of CO(2) from CH(4) using amino acid salt solutions as competitive absorption liquid to alkanol amine solutions. Amino acids, such as sarcosine, have the same functionality as alkanol amines (e.g., monoethanolamine=MEA), but in contrast, they exhibit a better oxidative stability and resistance to degradation. In addition, they can be made nonvolatile by adding a salt functionality, which significantly reduces the liquid loss due to evaporation at elevated temperatures in the desorber. Membrane contactor experiments using CO(2)/CH(4) feed mixtures to evaluate the overall process performance, including a full absorption/desorption cycle show that even without a temperature difference between absorber and desorber, a CO(2)/CH(4) selectivity of over 70 can be easily achieved with the sarcosine salt solution as absorption liquid. This selectivity reaches values of 120 at a temperature difference between absorber and desorber of 35 degrees C, compared to a value of only 60 for MEA under the same conditions. Although CO(2) permeance values are somewhat lower than the values obtained for MEA, the results clearly show the potential of amino acid salt solutions as competitive absorption liquids for the energy efficient removal of CO(2). In addition, due to the low absorption of CH(4) in sarcosine compared to MEA, the loss of CH(4) is reduced and significantly higher CH(4) product yields can be obtained. PMID:20623726

  13. Biomass waste carbon materials as adsorbents for CO2 capture under post-combustion conditions

    NASA Astrophysics Data System (ADS)

    Calvo-Muñoz, Elisa; García-Mateos, Francisco José; Rosas, Juana; Rodríguez-Mirasol, José; Cordero, Tomás

    2016-05-01

    A series of porous carbon materials obtained from biomass waste have been synthesized, with different morphologies and structural properties, and evaluated as potential adsorbents for CO2 capture in post-combustion conditions. These carbon materials present CO2 adsorption capacities, at 25 ºC and 101.3 kPa, comparable to those obtained by other complex carbon or inorganic materials. Furthermore, CO2 uptakes under these conditions can be well correlated to the narrow micropore volume, derived from the CO2 adsorption data at 0 ºC (VDRCO2). In contrast, CO2 adsorption capacities at 25 ºC and 15 kPa are more related to only pores of sizes lower than 0.7 nm. The capacity values obtained in column adsorption experiments were really promising. An activated carbon fiber obtained from Alcell lignin, FCL, presented a capacity value of 1.3 mmol/g (5.7 %wt). Moreover, the adsorption capacity of this carbon fiber was totally recovered in a very fast desorption cycle at the same operation temperature and total pressure and, therefore, without any additional energy requirement. Thus, these results suggest that the biomass waste used in this work could be successfully valorized as efficient CO2 adsorbent, under post-combustion conditions, showing excellent regeneration performance.

  14. Polyethyleneimine Incorporated Metal-Organic Frameworks Adsorbent for Highly Selective CO2 Capture

    PubMed Central

    Lin, Yichao; Yan, Qiuju; Kong, Chunlong; Chen, Liang

    2013-01-01

    A series of polyethyleneimine (PEI) incorporated MIL-101 adsorbents with different PEI loadings were reported for the first time in the present work. Although the surface area and pore volume of MIL-101 decreased significantly after loading PEI, all the resulting composites exhibited dramatically enhanced CO2 adsorption capacity at low pressures. At 100 wt% PEI loading, the CO2 adsorption capacity at 0.15 bar reached a very competitive value of 4.2 mmol g−1 at 25°C, and 3.4 mmol g−1 at 50°C. More importantly, the resulting adsorbents displayed rapid adsorption kinetics and ultrahigh selectivity for CO2 over N2 in the designed flue gas with 0.15 bar CO2 and 0.75 bar N2. The CO2 over N2 selectivity was up to 770 at 25°C, and 1200 at 50°C. We believe that the PEI based metal-organic frameworks is an attractive adsorbent for CO2 capture. PMID:23681218

  15. Hybrid heat exchange for the compression capture of CO2 from recirculated flue gas

    SciTech Connect

    Oryshchyn, Danylo B.; Ochs, Thomas L.; Summers, Cathy A.

    2004-01-01

    An approach proposed for removal of CO2 from flue gas cools and compresses a portion of a recirculated flue-gas stream, condensing its volatile materials for capture. Recirculating the flue gas concentrates SOx, H2O and CO2 while dramatically reducing N2 and NOx, enabling this approach, which uses readily available industrial components. A hybrid system of indirect and direct-contact heat exchange performs heat and mass transfer for pollutant removal and energy recovery. Computer modeling and experimentation combine to investigate the thermodynamics, heat and mass transfer, chemistry and engineering design of this integrated pollutant removal (IPR) system.

  16. Confinement of Ionic Liquids in Nanocages: Tailoring the Molecular Sieving Properties of ZIF-8 for Membrane-Based CO2 Capture.

    PubMed

    Ban, Yujie; Li, Zhengjie; Li, Yanshuo; Peng, Yuan; Jin, Hua; Jiao, Wenmei; Guo, Ang; Wang, Po; Yang, Qingyuan; Zhong, Chongli; Yang, Weishen

    2015-12-14

    Fine-tuning of effective pore size of microporous materials is necessary to achieve precise molecular sieving properties. Herein, we demonstrate that room temperature ionic liquids can be used as cavity occupants for modification of the microenvironment of MOF nanocages. Targeting CO2 capture applications, we tailored the effective cage size of ZIF-8 to be between CO2 and N2 by confining an imidazolium-based ionic liquid [bmim][Tf2 N] into ZIF-8's SOD cages by in-situ ionothermal synthesis. Mixed matrix membranes derived from ionic liquid-modified ZIF-8 exhibited remarkable combinations of permeability and selectivity that transcend the upper bound of polymer membranes for CO2 /N2 and CO2 /CH4 separation. We observed an unusual response of the membranes to varying pressure, that is, an increase in the CO2 /CH4 separation factor with pressure, which is highly desirable for practical applications in natural gas upgrading. PMID:26515558

  17. Prospective life-cycle modeling of a carbon capture and storage system using metal-organic frameworks for CO2 capture

    SciTech Connect

    Sathre, R; Masanet, E

    2013-01-01

    Metal-organic frameworks (MOFs) are promising new material media for carbon dioxide (CO2) capture. Their tunable adsorption patterns may allow relatively efficient separation of gases, e.g. from power plant exhaust. Here we conduct scenario-based prospective life-cycle system modeling to estimate the potentials and implications of large-scale MOF application for post-combustion carbon capture and storage (CCS), and estimate the source and magnitude of uncertainties. The methodological approach includes parametric system modeling to quantify relations between system components; scenario projections of plausible pathways for system scale-up; proxy data on analogous materials and processes; and uncertainty analysis of parameter significance. We estimate the system-wide material and energy flows and economic costs associated with projected large-scale CCS deployment. We compare the performance of a MOF-based system to currently more mature amine-based capture technology. We discuss balancing two critical factors that determine the success of CO2 capture media: thermodynamic efficiency of the capture/regeneration cycle, and life-cycle embodied energy and cost of the material and its ancillary systems.

  18. High CO2-capture ability of a porous organic polymer bifunctionalized with carboxy and triazole groups.

    PubMed

    Xie, Lin-Hua; Suh, Myunghyun Paik

    2013-08-26

    A new porous organic polymer, SNU-C1, incorporating two different CO2 -attracting groups, namely, carboxy and triazole groups, has been synthesized. By activating SNU-C1 with two different methods, vacuum drying and supercritical-CO2 treatment, the guest-free phases, SNU-C1-va and SNU-C1-sca, respectively, were obtained. Brunauer-Emmett-Teller (BET) surface areas of SNU-C1-va and SNU-C1-sca are 595 and 830 m(2) g(-1), respectively, as estimated by the N2-adsorption isotherms at 77 K. At 298 K and 1 atm, SNU-C1-va and SNU-C1-sca show high CO2 uptakes, 2.31 mmol  g(-1) and 3.14 mmol  g(-1), respectively, the high level being due to the presence of abundant polar groups (carboxy and triazole) exposed on the pore surfaces. Five separation parameters for flue gas and landfill gas in vacuum-swing adsorption were calculated from single-component gas-sorption isotherms by using the ideal adsorbed solution theory (IAST). The data reveal excellent CO2-separation abilities of SNU-C1-va and SNU-C1-sca, namely high CO2-uptake capacity, high selectivity, and high regenerability. The gas-cycling experiments for the materials and the water-treated samples, experiments that involved treating the samples with a CO2-N2 gas mixture (15:85, v/v) followed by a pure N2 purge, further verified the high regenerability and water stability. The results suggest that these materials have great potential applications in CO2 separation. PMID:23881821

  19. Synthesis and characterization of MOF-aminated graphite oxide composites for CO2 capture

    NASA Astrophysics Data System (ADS)

    Zhao, Yunxia; Ding, Huiling; Zhong, Qin

    2013-11-01

    A kind of metal-organic frameworks (MOF-5) and aminated graphite oxide (AGO) composites were prepared for CO2 capture to mitigate global warming. MOF-5, MOF-5/GO (composite of MOF-5 and graphite oxide) and MOF-5/AGO samples were characterized by X-ray powder diffraction (XRD), infrared spectroscopy (IR), scanning electron microscope (SEM), nitrogen adsorption as well as thermogravimetric analysis to figure out their chemistry and structure information. Three types of samples with suitable specific surface area and pore diameter were chosen to test CO2 adsorption performance and stability under humidity conditions. The results indicate that high surface area and pore volume, pore similar in size to the size of gas adsorbate, and extra reactive sites modified in the composites contributes to the high CO2 capacity. Besides, the composites involved by GO or AGO show better anti-moisture performance than the parent MOF.

  20. The Black Lake (Quebec, Canada) mineral carbonation experimental station: CO2 capture in mine waste

    NASA Astrophysics Data System (ADS)

    Beaudoin, G.; Constantin, M.; Duchesne, J.; Dupuis, C.; Entrazi, A.; Gras, A.; Huot, F.; Fortier, R.; Hebert, R.; Larachi, F.; Lechat, K.; Lemieux, J. M.; Molson, J. W. H.; Maldague, X.; Therrien, R.; Assima, G. P.

    2014-12-01

    Passive mineral carbonation of chrysotile mining and milling waste was discovered at the Black Lake mine, southern Québec, 10 years ago. Indurated crusts were found at the surface and within waste piles where mineral and rock fragments are cemented by hydrated magnesium carbonates. A long-term research program has yielded significant insight into the process of CO2 capture from the atmosphere, and how it can be implemented during mining operations. Laboratory experiments show that the waste mineralogy is crucial, brucite being more reactive than serpentine. Partial water saturation, circa 40%, is also critical to dissolve magnesium from minerals, and transport aqueous CO2 to precipitation sites. Grain armoring by iron oxidation induced by dissolved oxygen prevents further reaction. Two experimental cells constructed with milling waste and fitted with various monitoring probes (T, H2O content, leachate) and gas sampling ports, have been monitored for more than 3 years, along with environmental conditions. The interstitial gas in the cells remains depleted in CO2 indicating continuous capture of ambient atmospheric CO2 at rates faster than advection to reaction sites. The energy released by the exothermic mineral carbonation reactions has been observed both in laboratory experiments (up to 4 °C) and in the field. Warm air, depleted to 10 ppmv CO2, vents at the surface of the waste piles, indicating reaction with atmospheric CO2 deep inside the piles. A thermal anomaly, detected by airborne infrared and coincident with a known venting area, was selected for locating a 100 m deep borehole fitted with sensor arrays to monitor active mineral carbonation within the pile. The borehole has intersected areas where mineral carbonation has indurated the milling waste. The borehole will be monitored for the next 3 years to better understand the mineral carbonation process, and its potential to yield recoverable geothermal energy in mining environments.

  1. Analysis of CO2 Separation from Flue Gas, Pipeline Transportation, and Sequestration in Coal

    SciTech Connect

    Eric P. Robertson

    2007-09-01

    This report was written to satisfy a milestone of the Enhanced Coal Bed Methane Recovery and CO2 Sequestration task of the Big Sky Carbon Sequestration project. The report begins to assess the costs associated with separating the CO2 from flue gas and then injecting it into an unminable coal seam. The technical challenges and costs associated with CO2 separation from flue gas and transportation of the separated CO2 from the point source to an appropriate sequestration target was analyzed. The report includes the selection of a specific coal-fired power plant for the application of CO2 separation technology. An appropriate CO2 separation technology was identified from existing commercial technologies. The report also includes a process design for the chosen technology tailored to the selected power plant that used to obtain accurate costs of separating the CO2 from the flue gas. In addition, an analysis of the costs for compression and transportation of the CO2 from the point-source to an appropriate coal bed sequestration site was included in the report.

  2. Detection of CO2 leaks from carbon capture and storage sites to the atmosphere with combined CO2 and O2 measurements

    NASA Astrophysics Data System (ADS)

    van Leeuwen, Charlotte; Meijer, Harro A. J.

    2015-04-01

    One of the main issues in carbon capture and storage (CCS) is the possibility of leakage of CO2 from the storage reservoir to the atmosphere, both from a public health and a climate change combat perspective. Detecting these leaks in the atmosphere is difficult due to the rapid mixing of the emitted CO2 with the surrounding air masses and the high natural variability of the atmospheric CO2 concentration. Instead of measuring only the CO2 concentration of the atmosphere, its isotopes or chemical tracers that are released together with the CO2, our method uses O2 measurements in addition to CO2 measurements to detect a leak from a CCS site. CO2 and O2 are coupled in most processes on earth. In photosynthesis, plants take up CO2 and release O2 at the same time. In respiration and fossil fuel burning, O2 is consumed while CO2 is released. In case of a leak from a CCS site, however, there is no relationship between CO2 and O2. A CO2 leak can therefore be distinguished from other sources of CO2 by looking at the atmospheric CO2-O2 ratio. A natural increase of the CO2 concentration is accompanied by a drop in the O2 concentration, while an increase in the CO2 concentration caused by a leak from a CCS site does not have any effect on the O2 concentration. To demonstrate this leak detection strategy we designed and built a transportable CO2 and O2 measurement system, that is capable of measuring the relatively minute (ppm's variations on a 21% concentration) changes in the O2 concentration. The system comprises of three cases that contain the instrumentation and gas handling equipment, the gas cylinders used as reference and calibration gases and a drying system, respectively. Air is pumped to the system from an air inlet that is placed in a small tower in the field. At the conference, we will demonstrate the success of leak detection with our system by showing measurements of several CO2 release experiments, where CO2 was released at a small distance from the air inlet of

  3. Hydrothermal synthesis of N-doped spherical carbon from carboxymethylcellulose for CO2 capture

    NASA Astrophysics Data System (ADS)

    Wu, Qiong; Li, Wei; Liu, Shouxin; Jin, Chunde

    2016-04-01

    Spherical carbonaceous adsorbents (CSn) with micro-porosity developed for CO2 capture were prepared by a simple hydrothermal carbonization of carboxymethylcellulose (CMC) in the presence of urea, and activated in a high temperature N2 atmosphere. The effects of specific surface area, pore structure, and N content on the CO2 adsorption capacity were systematically investigated. Urea was found to react with surface carbonyl groups and other intermediate products generated by CMC hydrothermal carbonization, which produced highly spherical morphologies that also exhibited some ordered lattice structures. The particle size of N-doped CSn was larger than that of particles prepared without urea. Nitrogen was mainly present in pyridine (N-6), pyrrolic/pyridone (N-5) and quaternary (N-Q) forms. The high CO2 capture capacity was produced by a combination of N-doping and developing micro-pore structures. At an adsorption pressure of 1 bar, the capacity was dominated by the micro-porosity. However, during initial, lower pressures the N content dominated the CO2 adsorption capacity.

  4. Characterization of carbonic anhydrase II from Chlorella vulgaris in bio-CO2 capture.

    PubMed

    Li, Li; Fu, Ming-Lai; Zhao, Yong-Hao; Zhu, Yun-Tian

    2012-11-01

    Carbonic anhydrase II (CA II) can catalyze the reversible hydration reaction of CO(2) at a maximum of 1.4 × 10(6) molecules of CO(2) per second. The crude intracellular enzyme extract containing CA II was derived from Chlorella vulgaris. A successful CO(2) capture experiment with the presence of calcium had been conducted on the premise that the temperature was conditioned at a scope of 30-40 °C, that the biocatalyst-nurtured algal growth period lasted 3 days, and that pH ranged from7.5 to 8.5. Ions of K(+), Na(+), Ca(2+), Co(2+), Cu(2+), Fe(3+), Mg(2+), Mn(2+), and Zn(2+) at 0.01, 0.1, and 0.5 M were found to exhibit no more than 30 % inhibition on the residual activity of the biocatalyst. It is reasonable to expect that calcification catalyzed by microalgae presents an alternative to geological carbon capture and sequestration through a chain of fundamental researches carried on under the guidance of sequestration technology. PMID:22821342

  5. CO2 Capture Using Electric Fields: Low-Cost Electrochromic Film on Plastic for Net-Zero Energy Building

    SciTech Connect

    2010-01-01

    Broad Funding Opportunity Announcement Project: Two faculty members at Lehigh University created a new technique called supercapacitive swing adsorption (SSA) that uses electrical charges to encourage materials to capture and release CO2. Current CO2 capture methods include expensive processes that involve changes in temperature or pressure. Lehigh University’s approach uses electric fields to improve the ability of inexpensive carbon sorbents to trap CO2. Because this process uses electric fields and not electric current, the overall energy consumption is projected to be much lower than conventional methods. Lehigh University is now optimizing the materials to maximize CO2 capture and minimize the energy needed for the process.

  6. Co-location of air capture, subseafloor CO2 sequestration, and energy production on the Kerguelen plateau.

    PubMed

    Goldberg, David S; Lackner, Klaus S; Han, Patrick; Slagle, Angela L; Wang, Tao

    2013-07-01

    Reducing atmospheric CO2 using a combination of air capture and offshore geological storage can address technical and policy concerns with climate mitigation. Because CO2 mixes rapidly in the atmosphere, air capture could operate anywhere and in principle reduce CO2 to preindustrial levels. We investigate the Kerguelen plateau in the Indian Ocean, which offers steady wind resources, vast subseafloor storage capacities, and minimal risk of economic damages or human inconvenience and harm. The efficiency of humidity swing driven air capture under humid and windy conditions is tested in the laboratory. Powered by wind, we estimate ∼75 Mt CO2/yr could be collected using air capture and sequestered below seafloor or partially used for synfuel. Our analysis suggests that Kerguelen offers a remote and environmentally secure location for CO2 sequestration using renewable energy. Regional reservoirs could hold over 1500 Gt CO2, sequestering a large fraction of 21st century emissions. PMID:23745611

  7. Pilot-scale production of mesoporous silica-based adsorbent for CO2 capture

    NASA Astrophysics Data System (ADS)

    Wang, Hou Chuan; Lu, Chungsying; Bai, Hsunling; Hwang, Jyh Feng; Lee, Hsiu Hsia; Chen, Wang; Kang, Yuhao; Chen, Shing-Ting; Su, Fengsheng; Kuo, Shih-Chun; Hu, Fang-Chun

    2012-07-01

    This study presents a pilot-scale spray drying system designed to manufacture spherical mesoporous silica particles (MSP) that is capable of producing up to 100 g per hour. The MSP fabricated via a nozzle pressure of 4 kg/cm2 and a drying temperature of 200 °C possess a high specific area of 1012 m2/g, a narrow pore size distribution with an average pore diameter of 2.4 nm, and large pore volume of 0.81 cm3/g. They were further modified with a tetraethylenepentamine (TEPA-MSP) to enhance CO2 adsorption selectivity from gas streams. The adsorption capacity of 15% CO2 on TEPA-MSP was significantly influenced by adsorption temperature and water vapor of air streams, and reached a maximum of 87.05 mg/g (1.98 mmol/g) at 60 °C and 129.19 mg/g (2.94 mmol/g) at a water vapor of 6.98%. The adsorption capacities and the physicochemical properties of TEPA-MSP were preserved through 20 cycles of adsorption-desorption operation. A comparative study revealed that the TEPA-MSP had better adsorption performance of 15% CO2 than the TEPA-modified granular activated carbon and zeolite. These results suggest that the TEPA-MSP can be stably employed in the prolonged cyclic CO2 adsorption and that they possess good potential for CO2 capture from flue gas.

  8. Amphiphilic Graft Copolymer Nanospheres: From Colloidal Self-Assembly to CO2 Capture Membranes.

    PubMed

    Jeon, Harim; Kim, Dong Jun; Park, Min Su; Ryu, Du Yeol; Kim, Jong Hak

    2016-04-13

    Colloidal nanosphere self-assembly effectively generates ordered nanostructures, prompting tremendous interest in many applications such as photonic crystals and templates for inverse opal fabrication. Here we report the self-assembly of low-cost, graft copolymer nanospheres for CO2 capture membranes. Specifically, poly(dimethylsiloxane)-graft-poly(4-vinylpyridine) (PDMS-g-P4VP) is synthesized via one-pot, free radical dispersion polymerization to give discrete monodisperse nanospheres. These nanospheres comprise a surface-anchored highly permeable PDMS layer and internal CO2-philic P4VP spherical core. Their diameter is controllable below the submicrometer range by varying grafting ratios. The colloidal dispersion forms a long-range, close-packed hexagonal array on a substrate by inclined deposition and convective assembly. The array shows dispersion medium-dependent packing characteristics. A thermodynamic correlation is determined using different solvents to obtain stable PDMS-g-P4VP dispersions and interpreted in terms of Flory-Huggins interaction parameter. As a proof-of-concept, the implementation of these nanospheres into membranes simultaneously enhances the CO2 permeability and CO2/N2 selectivity of PDMS-based transport matrixes. Upon physical aging of the solution, the CO2/N2 selectivity is improved up to 26, one of the highest values for highly permeable PDMS-based polymeric membranes. PMID:27004536

  9. Bench-Scale Process for Low-Cost Carbon Dioxide (CO2) Capture Using a Phase-Changing Absorbent

    SciTech Connect

    Westendorf, Tiffany; Caraher, Joel; Chen, Wei; Farnum, Rachael; Perry, Robert; Spiry, Irina; Wilson, Paul; Wood, Benjamin

    2015-03-31

    The objective of this project is to design and build a bench-scale process for a novel phase-changing aminosilicone-based CO2-capture solvent. The project will establish scalability and technical and economic feasibility of using a phase-changing CO2-capture absorbent for post-combustion capture of CO2 from coal-fired power plants with 90% capture efficiency and 95% CO2 purity at a cost of $40/tonne of CO2 captured by 2025 and a cost of <$10/tonne of CO2 captured by 2035. In the first budget period of this project, the bench-scale phase-changing CO2 capture process was designed using data and operating experience generated under a previous project (ARPA-e project DE-AR0000084). Sizing and specification of all major unit operations was completed, including detailed process and instrumentation diagrams. The system was designed to operate over a wide range of operating conditions to allow for exploration of the effect of process variables on CO2 capture performance.

  10. Evaluation of Metal-Organic Frameworks and Porous Polymer Networks for CO2 -Capture Applications.

    PubMed

    Verdegaal, Wolfgang M; Wang, Kecheng; Sculley, Julian P; Wriedt, Mario; Zhou, Hong-Cai

    2016-03-21

    This manuscript presents experimental data for 20 adsorption materials (metal-organic frameworks, porous polymer networks, and Zeolite-5A), including CO2 and N2 isotherms and heat capacities. With input from only experimental data, working capacities per energy for each material were calculated. Furthermore, by running seven different carbon-capture scenarios in which the initial flue-gas composition and process temperature was systematically changed, we present a range of performances for each material and quantify how sensitive each is to these varying parameters. The presented calculations provide researchers with a tool to investigate promising carbon-capture materials more easily and completely. PMID:26840979

  11. CO2 capture and conversion with a multifunctional polyethyleneimine-tethered iminophosphine iridium catalyst/adsorbent.

    PubMed

    McNamara, Nicholas D; Hicks, Jason C

    2014-04-01

    Tunable, multifunctional materials able to capture CO2 and subsequently catalyze its conversion to formic acid were synthesized by the modification of branched polyethyleneimine (PEI) with an iminophosphine ligand coordinated to an Ir precatalyst. The molecular weight of the PEI backbone was an important component for material stability and catalytic activity, which were inversely related. The amine functionalities on PEI served three roles: 1) primary amines were used to tether the ligand and precatalyst, 2) amines were used to capture CO2 , and 3) amines served as a base for formate stabilization during catalysis. Ligand studies on imine and phosphine based ligands showed that a bidentate iminophosphine ligand resulted in the highest catalytic activity. X-ray photoelectron spectroscopy revealed that an increase in Ir 4f binding energy led to an increase in catalytic activity, which suggests that the electronics of the metal center play a significant role in catalysis. Catalyst loading studies revealed that there is a critical balance between free amines and ligand-metal sites that must be reached to optimize catalytic activity. Thus, it was found that the CO2 capture and conversion abilities of these materials could be optimized for reaction conditions by tuning the structure of the PEI-tethered materials. PMID:24591345

  12. Spectroscopic Investigation into Oxidative Degradation of Silica-Supported Amine Sorbents for CO2 Capture

    PubMed Central

    Srikanth, Chakravartula S; Chuang, Steven S C

    2012-01-01

    Oxidative degradation characteristics of silica-supported amine sorbents with varying amounts of tetraethylenepentamine (TEPA) and polyethylene glycol (PEG; P200 or P600 represents PEG with molecular weights of 200 or 600) have been studied by IR and NMR spectroscopy. Thermal treatment of the sorbents and liquid TEPA at 100 °C for 12 h changed their color from white to yellow. The CO2 capture capacity of the TEPA/SiO2 sorbents (i.e., SiO2-supported TEPA with a TEPA/SiO2 ratio of 25:75) decreased by more than 60 %. IR and NMR spectroscopy studies showed that the yellow color of the degraded sorbents resulted from the formation of imide species. The imide species, consisting of NH associated with two C—O functional groups, were produced from the oxidation of methylene groups in TEPA. Imide species on the degraded sorbent are not capable of binding CO2 due to its weak basicity. The addition of P200 and P600 to the supported amine sorbents improved both their CO2 capture capacities and oxidative degradation resistance. IR spectroscopy results also showed that TEPA was immobilized on the SiO2 surface through hydrogen bonding between amine groups and the silanol groups of SiO2. The OH groups of PEG interact with NH2/NH of TEPA through hydrogen bonding. Hydrogen bonds disperse TEPA on SiO2 and block O2 from accessing TEPA for oxidation. Oxidative degradation resistance and CO2 capture capacity of the supported amine sorbents can be optimized through adjusting the ratio of hydroxyl to amine groups in the TEPA/PEG mixture. PMID:22744858

  13. Multiwell 14CO2-capture assay for evaluation of substrate oxidation rates of cells in culture.

    PubMed

    Collins, C L; Bode, B P; Souba, W W; Abcouwer, S F

    1998-05-01

    14CO2 capture is commonly used to evaluate the cellular oxidation rate of respiratory substrates. A modification of the established 14CO2-capture method was developed that enables the use of cells in adherent culture and easy analysis of multiple samples under different culture conditions. The use of commercially available culture and filter plates designed for use in a multiplate scintillation spectrophotometer enabled substrate oxidation rates to be evaluated for cells in a 24-well plate format without the need to dislodge the cells from the culture substrate as is required in traditional methods. Evaluation of radioactivity captured in potassium hydroxide-saturated filters was accomplished by adding scintillation fluid to the filter plate wells and counting. Alternatively, filters could be removed and placed in vials for evaluation in a conventional scintillation counter. This method was applied to the oxidation of 14C-glutamine by human breast cell lines and demonstrated concentration-dependent linear accumulation of captured counts. PMID:9591130

  14. Direct Air Capture of CO2 - an Overview of Carbon Engineering's Technology and Pilot Plant Development

    NASA Astrophysics Data System (ADS)

    Holmes, G.; Corless, A.

    2014-12-01

    At Carbon Engineering, we are developing and commercializing technology to scrub CO2 directly from atmospheric air at industrial scale. By providing atmospheric CO2 for use in fuel production, we can enable production of transportation fuels with ultra-low carbon intensities, which command price premiums in the growing set of constrained fuels markets such as California's LCFS. We are a Calgary based startup founded in 2009 with 10 employees, and we are considered a global leader in the direct air capture (DAC) field. We will review CE's DAC technology, based on a wet-scrubbing "air contactor" which absorbs CO2 into aqueous solution, and a chemical looping "regeneration" component, which liberates pure CO2 from this aqueous solution while re-making the original absorption chemical. CE's DAC tecnology exports purified atmospheric CO2, combined with the combustion CO2 from plant energy usage, as the end product. We will also discuss CE's 2014-2015 end-to-end Pilot Demonstration Unit. This is a $7M technology demonstration plant that CE is building with the help of key industrial partners and equipment vendors. Vendor design and engineering requirements have been used to specify the pilot air contactor, pellet reactor, calciner, and slaker modules, as well as auxiliary systems. These modules will be run for several months to obtain the engineering and performance data needed for subsequent commercial plant design, as well as to test the residual integration risks associated with CE's process. By the time of the AGU conference, the pilot is expected to be in late stages of fabrication or early stages of site installation.

  15. A Highly Permeable Aligned Montmorillonite Mixed-Matrix Membrane for CO2 Separation.

    PubMed

    Qiao, Zhihua; Zhao, Song; Wang, Jixiao; Wang, Shichang; Wang, Zhi; Guiver, Michael D

    2016-08-01

    Highly permeable montmorillonite layers bonded and aligned with the chain stretching orientation of polyvinylamineacid are immobilized onto a porous polysulfone substrate to fabricate aligned montmorillonite/polysulfone mixed-matrix membranes for CO2 separation. High-speed gas-transport channels are formed by the aligned interlayer gaps of the modified montmorillonite, through which CO2 transport primarily occurs. High CO2 permeance of about 800 GPU is achieved combined with a high mixed-gas selectivity for CO2 that is stable over a period of 600 h and independent of the water content in the feed. PMID:27312314

  16. Immobilization of carbonic anhydrase on carboxyl-functionalized ferroferric oxide for CO2 capture.

    PubMed

    Lv, Bihong; Yang, Zhaoren; Pan, Fujun; Zhou, Zuoming; Jing, Guohua

    2015-08-01

    New materials of Fe3O4 magnetic microspheres were functionalized with carboxyl and prepared for carbonic anhydrase (CA) immobilization to capture CO2. The optimum conditions for immobilization, such as carrier dose, enzyme dose, pH, shaking speed, temperature and contact time, were determined. The pH and thermal stability of the free and the immobilized CA were compared. The results presented that the immobilized CA had a better enzyme activity, a higher pH and thermal stability than that of the free CA. Meanwhile, CO2 capture was respectively enhanced by the free and the immobilized CA in tris(hydroxymethyl) aminomethane (Tris) buffer solution. Moreover, the immobilized CA maintained 58.5% of its initial catalytic ability even after ten recovery cycles due to the protest of the magnetic microspheres. All the results confirmed the potential use of the carboxyl-functionalized Fe3O4 magnetic microspheres immobilized CA to remove CO2 from air or flue gas. PMID:26038102

  17. Life cycle assessment of CO2 capture and utilization: a tutorial review.

    PubMed

    von der Assen, Niklas; Voll, Philip; Peters, Martina; Bardow, André

    2014-12-01

    Capturing CO2 and using it as an alternative carbon feedstock for chemicals, fuels and materials has the potential to reduce both CO2 emissions and fossil resource depletion. To assess the actual environmental benefits of CO2 capture and utilization (CCU), life cycle assessment (LCA) is considered as suitable metric. To enhance the use of LCA of CCU, this tutorial review gives a jargon-free introduction of LCA of CCU directed at LCA novices. Nine particularly important aspects for conducting an LCA of CCU are identified and illustrated with CCU examples. These aspects, phrased as action items, can serve LCA novices as a checklist through all steps in LCA of CCU: from defining the LCA purpose and the system boundaries, over data collection and environmental impact computation, to interpretation and sensitivity analysis of the results. Finally, in the context of CCU, an outlook is given on recent developments in LCA that aim to cover all pillars of sustainability (people, planet, and profit). PMID:24441866

  18. Sequestration of CO2 discharged from anode by algal cathode in microbial carbon capture cells (MCCs).

    PubMed

    Wang, Xin; Feng, Yujie; Liu, Jia; Lee, He; Li, Chao; Li, Nan; Ren, Nanqi

    2010-08-15

    Due to increased discharge of CO(2) is incurring problems, CO(2) sequestration technologies require substantial development. By introducing anodic off gas into an algae grown cathode (Chlorella vulgaris), new microbial carbon capture cells (MCCs) were constructed and demonstrated here to be an effective technology for CO(2) emission reduction with simultaneous voltage output without aeration (610+/-50 mV, 1000 Omega). Maximum power densities increased from 4.1 to 5.6 W/m(3) when the optical density (OD) of cathodic algae suspension increased from 0.21 to 0.85 (658 nm). Compared to a stable voltage of 706+/-21 mV (1000 Omega) obtained with cathodic dissolved oxygen (DO) of 6.6+/-1.0 mg/L in MCC, voltage outputs decreased from 654 to 189 mV over 70 h in the control reactor (no algae) accompanied with a decrease in DO from 7.6 to 0.9 mg/L, indicating that cathode electron acceptor was oxygen. Gas analysis showed that all the CO(2) generated from anode was completely eliminated by catholyte, and the soluble inorganic carbon was further converted into algal biomass. These results showed the possibility of a new method for simultaneous carbon fixing, power generation and biodiesel production during wastewater treatment without aeration. PMID:20547055

  19. DEVELOPMENT OF MESOPOROUS MEMBRANE MATERIALS FOR CO2 SEPARATION

    SciTech Connect

    Wei-Heng Shih; Tejas Patil; Qiang Zhao

    2003-03-25

    The huge emissions of carbon dioxide from fossil fuel fired power plants and industrial plants over the last century have resulted in an increase of the atmospheric carbon dioxide concentration. Climatological modeling work has predicted severe climate disruption as a result of the trapping of heat due to CO{sub 2}. As an attempt to address this global warming effect, DOE has initiated the Vision 21 concept for future power plants. We first synthesized mesoporous aluminosilicates that have high surface area and parallel pore channels for membrane support materials. Later we synthesized microporous aluminosilicates as the potential thin membrane materials for selective CO{sub 2} adsorption. The pore size is controlled to be less that 1 nm so that the adsorption of CO{sub 2} on the pore wall will block the passage of N{sub 2}. Mesoporous and precipitated alumina were synthesized as the base material for CO{sub 2} adsorbent. The porous alumina is doped with Ba to enhance its CO{sub 2} affinity due to the basicity of Ba. It is shown by gas chromatograph (GC) that the addition of Ba enhances the separation CO{sub 2} from N{sub 2}. It was found that mesoporous alumina has larger specific surface area and better selectivity of CO{sub 2} than precipitated alumina. Ba improves the affinity of mesoporous alumina with CO{sub 2}. Phase may play an important role in selective adsorption of CO{sub 2}. It is speculated that mesoporous alumina is more reactive than precipitated alumina creating the xBaO {center_dot}Al{sub 2}O{sub 3} phase that may be more affinitive to CO{sub 2} than N{sub 2}. On the other hand, the barium aluminates phase (Ba{sub 3}Al{sub 2}O{sub 6}) in the mesoporous sample does not help the adsorption of CO{sub 2}. Microporous aluminosilicate was chosen as a suitable candidate for CO{sub 2}/N{sub 2} separation because the pore size is less than 10 {angstrom}. If a CO{sub 2} adsorbent is added to the microporous silica, the adsorption of CO{sub 2} can block the

  20. Dual Phase Membrane for High Temperature CO2 Separation

    SciTech Connect

    Jerry Lin

    2007-06-30

    This project aimed at synthesis of a new inorganic dual-phase carbonate membrane for high temperature CO{sub 2} separation. Metal-carbonate dual-phase membranes were prepared by the direct infiltration method and the synthesis conditions were optimized. Permeation tests for CO{sub 2} and N{sub 2} from 450-750 C showed very low permeances of those two gases through the dual-phase membrane, which was expected due to the lack of ionization of those two particular gases. Permeance of the CO{sub 2} and O{sub 2} mixture was much higher, indicating that the gases do form an ionic species, CO{sub 3}{sup 2-}, enhancing transport through the membrane. However, at temperatures in excess of 650 C, the permeance of CO{sub 3}{sup 2-} decreased rapidly, while predictions showed that permeance should have continued to increase with temperature. XRD data obtained from used membrane indicated that lithium iron oxides formed on the support surface. This lithium iron oxide layer has a very low conductivity, which drastically reduces the flow of electrons to the CO{sub 2}/O{sub 2} gas mixture; thus limiting the formation of the ionic species required for transport through the membrane. These results indicated that the use of stainless steel supports in a high temperature oxidative environment can lead to decreased performance of the membranes. This revelation created the need for an oxidation resistant support, which could be gained by the use of a ceramic-type membrane. Work was extended to synthesize a new inorganic dual-phase carbonate membrane for high temperature CO{sub 2} separation. Helium permeance of the support before and after infiltration of molten carbonate are on the order of 10{sup -6} and 10{sup -10} moles/m{sup 2} {center_dot} Pa {center_dot} s respectively, indicating that the molten carbonate is able to sufficiently infiltrate the membrane. It was found that La{sub 0.6}Sr{sub 0.4}Co{sub 0.8}Fe{sub 0.2}O{sub 3-{delta}} (LSCF) was a suitable candidate for the support

  1. A Fine-Tuned Fluorinated MOF Addresses the Needs for Trace CO2 Removal and Air Capture Using Physisorption.

    PubMed

    Bhatt, Prashant M; Belmabkhout, Youssef; Cadiau, Amandine; Adil, Karim; Shekhah, Osama; Shkurenko, Aleksander; Barbour, Leonard J; Eddaoudi, Mohamed

    2016-07-27

    The development of functional solid-state materials for carbon capture at low carbon dioxide (CO2) concentrations, namely, from confined spaces (<0.5%) and in particular from air (400 ppm), is of prime importance with respect to energy and environment sustainability. Herein, we report the deliberate construction of a hydrolytically stable fluorinated metal-organic framework (MOF), NbOFFIVE-1-Ni, with the appropriate pore system (size, shape, and functionality), ideal for the effective and energy-efficient removal of trace carbon dioxide. Markedly, the CO2-selective NbOFFIVE-1-Ni exhibits the highest CO2 gravimetric and volumetric uptake (ca. 1.3 mmol/g and 51.4 cm(3) (STP) cm(-3)) for a physical adsorbent at 400 ppm of CO2 and 298 K. Practically, NbOFFIVE-1-Ni offers the complete CO2 desorption at 328 K under vacuum with an associated moderate energy input of 54 kJ/mol, typical for the full CO2 desorption in conventional physical adsorbents but considerably lower than chemical sorbents. Noticeably, the contracted square-like channels, affording the close proximity of the fluorine centers, permitted the enhancement of the CO2-framework interactions and subsequently the attainment of an unprecedented CO2 selectivity at very low CO2 concentrations. The precise localization of the adsorbed CO2 at the vicinity of the periodically aligned fluorine centers, promoting the selective adsorption of CO2, is evidenced by the single-crystal X-ray diffraction study on NbOFFIVE-1-Ni hosting CO2 molecules. Cyclic CO2/N2 mixed-gas column breakthrough experiments under dry and humid conditions corroborate the excellent CO2 selectivity under practical carbon capture conditions. Pertinently, the notable hydrolytic stability positions NbOFFIVE-1-Ni as the new benchmark adsorbent for direct air capture and CO2 removal from confined spaces. PMID:27388208

  2. Combustion Characteristics of Oxy-fuel Burners for CO2 Capturing Boilers

    NASA Astrophysics Data System (ADS)

    Ahn, Joon; Kim, Hyouck Ju; Choi, Kyu Sung

    Oxy-fuel boilers have been developed to capture CO2 from the exhaust gas. A 50 kW class model burner has been developed and tested in a furnace type boiler. The burner has been scaled up to 0.5 and 3 MW class for fire-tube type boilers. The burners are commonly laid out in a coaxial type to effectively heat the combustion chamber of boilers. Burners are devised to support air and oxy-fuel combustion modes for the retrofitting scenario. FGR (flue gas recirculation) has been tried during the scale-up procedure. Oxy-fuel combustion yields stretched flame to uniformly heat the combustion chamber. It also provides the high CO2 concentration, which is over 90% in dry base. However, pure oxy-fuel combustion increases NO concentration, because of the reduced flow rate. The FGR can suppress the thermal NOx induced by the infiltration of the air.

  3. CO2 Capturing and Mineralization by (Mg)-Phyllosilicate Coated with Fabrics.

    PubMed

    Song, Dongsu; Lee, Young-Chul; Park, Seung Bin; Han, Jong-In

    2016-05-01

    To promote the practicality of magnesium (Mg)-phyllosilicate as a potent carbonation agent, two inexpensive cotton and nylon fabrics are selected and examined to assess their feasibility for use as supporting media of Mg-phyllosilicate. Mg-phyllosilicate is coated onto the fabrics via a sol-gel method, whose mechanism is explained. The characteristics of the Mg-phyllosilicate coated cotton, along with those of the carbonation products, are explored. Mg-phyllosilicate is found to mediate the carbon dioxide (CO2) mineralization process actively, even on cotton of a supporting material. Conclusively, the obtained results clearly support the potential of mineralization as a feasible option for capturing CO2, in particular with the abiotic catalyst of Mg-phyllosilicate coated onto flexible cotton. PMID:27483872

  4. DEVELOPMENT OF MESOPOROUS MEMBRANE MATERIALS FOR CO2 SEPARATION

    SciTech Connect

    Wei-Heng Shih; Qiang Zhao; Nanlin Wang

    2002-05-01

    Mesoporous and precipitated alumina were synthesized as the base material for CO{sub 2} adsorbent. The porous alumina is doped with Ba to enhance it CO{sub 2} affinity due to the basicity of Ba. it is shown by gas chromatograph (GC) that the addition of Ba enhances the separation CO{sub 2} from N{sub 2}. It was found that mesoporous alumina has larger specific surface area and better selectivity of CO{sub 2} than precipitated alumina. Ba improves the affinity of mesoporous alumina with CO{sub 2}. Phase may play an important role in selective adsorption of CO{sub 2}. It is speculated that mesoporous alumina is more reactive than precipitated alumina creating the xBaO {center_dot} Al{sub 2}O{sub 3} phase that may be more affinity to CO{sub 2} than N{sub 2}. On the other hand, the barium aluminate phase (Ba{sub 3}Al{sub 2}O{sub 6}) in the mesoporous sample does not help the adsorption of CO{sub 2}.

  5. Multiphase, multicomponent simulations and experiments of reactive flow, relevant for combining geologic CO2 sequestration with geothermal energy capture

    NASA Astrophysics Data System (ADS)

    Saar, Martin O.

    2011-11-01

    Understanding the fluid dynamics of supercritical carbon dioxide (CO2) in brine- filled porous media is important for predictions of CO2 flow and brine displacement during geologic CO2 sequestration and during geothermal energy capture using sequestered CO2 as the subsurface heat extraction fluid. We investigate multiphase fluid flow in porous media employing particle image velocimetry experiments and lattice-Boltzmann fluid flow simulations at the pore scale. In particular, we are interested in the motion of a drop (representing a CO2 bubble) through an orifice in a plate, representing a simplified porous medium. In addition, we study single-phase/multicomponent reactive transport experimentally by injecting water with dissolved CO2 into rocks/sediments typically considered for CO2 sequestration to investigate how resultant fluid-mineral reactions modify permeability fields. Finally, we investigate numerically subsurface CO2 and heat transport at the geologic formation scale.

  6. Commerical-Scale CO2 Capture and Sequestration for the Cement Industry

    SciTech Connect

    Adolfo Garza

    2010-07-28

    On June 8, 2009, DOE issued Funding Opportunity Announcement (FOA) Number DE-FOA-000015 seeking proposals to capture and sequester carbon dioxide from industrial sources. This FOA called for what was essentially a two-tier selection process. A number of projects would receive awards to conduct front-end engineering and design (FEED) studies as Phase I. Those project sponsors selected would be required to apply for Phase II, which would be the full design, construction, and operation of their proposed technology. Over forty proposals were received, and ten were awarded Phase I Cooperative Agreements. One of those proposers was CEMEX. CEMEX proposed to capture and sequester carbon dioxide (CO2) from one of their existing cement plants and either sequester the CO2 in a geologic formation or use it for enhanced oil recovery. The project consisted of evaluating their plants to identify the plant best suited for the demonstration, identify the best available capture technology, and prepare a design basis. The project also included evaluation of the storage or sequestration options in the vicinity of the selected plant.

  7. Dual Phase Membrane for High Temperature CO2 Separation

    SciTech Connect

    Jerry Y.S. Lin; Matthew Anderson

    2006-09-29

    Dual-phase membranes consisting of stainless steel supports infiltrated with molten carbonate have been shown to be selective to CO{sub 2} at high temperatures (400-650 C). However, over time at high temperatures, the formation of iron oxides on the surface of the stainless steel supports render the membranes ineffective. This report details synthesis and characteristics of dual-phase carbonate membrane with an oxidation resistant perovskite type ceramic (lanthanum-strontium-cobaltite-iron; LSCF) support. Porous LSCF supports were prepared from its powder synthesized by the citrate method. Both steady state permeation and mercury porosimetry confirmed that the LSCF membrane sintered at 900 C has pores large enough to absorb molten carbonate, yet small enough to retain the molten carbonate under high pressure conditions. Results of XRD analysis have shown that LSCF and the molten carbonate mixture do not react with each other at temperatures below 700 C. Four-point method conductivity tests indicate that the support material has sufficiently high electronic conductivity for this application. Li-Na-K carbonate was coated to the porous LSCF support by a liquid infiltration method. Helium permeance of the support before and after infiltration of molten carbonate are on the order of 10{sup -6} and 10{sup -10} moles/m{sup 2} {center_dot} Pa {center_dot} s respectively, indicating that the molten carbonate is able to sufficiently infiltrate the membrane. Preliminary high temperature permeation experiments indicate that the membrane does separate CO{sub 2} in the presence of O{sub 2}, with a maximum flux of 0.623 ml/cm{sup 2} {center_dot} min obtained at 850 C.

  8. The O2-assisted Al/CO2 electrochemical cell: A system for CO2 capture/conversion and electric power generation.

    PubMed

    Al Sadat, Wajdi I; Archer, Lynden A

    2016-07-01

    Economical and efficient carbon capture, utilization, and sequestration technologies are a requirement for successful implementation of global action plans to reduce carbon emissions and to mitigate climate change. These technologies are also essential for longer-term use of fossil fuels while reducing the associated carbon footprint. We demonstrate an O2-assisted Al/CO2 electrochemical cell as a new approach to sequester CO2 emissions and, at the same time, to generate substantial amounts of electrical energy. We report on the fundamental principles that guide operations of these cells using multiple intrusive electrochemical and physical analytical methods, including chronopotentiometry, cyclic voltammetry, direct analysis in real-time mass spectrometry, energy-dispersive x-ray spectroscopy, x-ray photoelectron spectroscopy, and coupled thermogravimetric analysis-Fourier transform infrared spectroscopy. On this basis, we demonstrate that an electrochemical cell that uses metallic aluminum as anode and a carbon dioxide/oxygen gas mixture as the active material in the cathode provides a path toward electrochemical generation of a valuable (C2) species and electrical energy. Specifically, we show that the cell first reduces O2 at the cathode to form superoxide intermediates. Chemical reaction of the superoxide with CO2 sequesters the CO2 in the form of aluminum oxalate, Al2(C2O4)3, as the dominant product. On the basis of an analysis of the overall CO2 footprint, which considers emissions associated with the production of the aluminum anode and the CO2 captured/abated by the Al/CO2-O2 electrochemical cell, we conclude that the proposed process offers an important strategy for net reduction of CO2 emissions. PMID:27453949

  9. The O2-assisted Al/CO2 electrochemical cell: A system for CO2 capture/conversion and electric power generation

    PubMed Central

    Al Sadat, Wajdi I.; Archer, Lynden A.

    2016-01-01

    Economical and efficient carbon capture, utilization, and sequestration technologies are a requirement for successful implementation of global action plans to reduce carbon emissions and to mitigate climate change. These technologies are also essential for longer-term use of fossil fuels while reducing the associated carbon footprint. We demonstrate an O2-assisted Al/CO2 electrochemical cell as a new approach to sequester CO2 emissions and, at the same time, to generate substantial amounts of electrical energy. We report on the fundamental principles that guide operations of these cells using multiple intrusive electrochemical and physical analytical methods, including chronopotentiometry, cyclic voltammetry, direct analysis in real-time mass spectrometry, energy-dispersive x-ray spectroscopy, x-ray photoelectron spectroscopy, and coupled thermogravimetric analysis–Fourier transform infrared spectroscopy. On this basis, we demonstrate that an electrochemical cell that uses metallic aluminum as anode and a carbon dioxide/oxygen gas mixture as the active material in the cathode provides a path toward electrochemical generation of a valuable (C2) species and electrical energy. Specifically, we show that the cell first reduces O2 at the cathode to form superoxide intermediates. Chemical reaction of the superoxide with CO2 sequesters the CO2 in the form of aluminum oxalate, Al2(C2O4)3, as the dominant product. On the basis of an analysis of the overall CO2 footprint, which considers emissions associated with the production of the aluminum anode and the CO2 captured/abated by the Al/CO2-O2 electrochemical cell, we conclude that the proposed process offers an important strategy for net reduction of CO2 emissions. PMID:27453949

  10. Carbonation of mantle peridotites: implications for permanent geological CO2 capture and storage

    NASA Astrophysics Data System (ADS)

    Paukert, A. N.; Matter, J. M.; Kelemen, P. B.; Marsala, P.; Shock, E.

    2012-12-01

    In situ carbonation of mantle peridotites serves as a natural analog to engineered mineral carbonation for geological CO2 capture and storage. For example, mantle peridotite in the Samail Ophiolite, Oman naturally captures and stores about 5x104 tons of atmospheric CO2 per year as carbonate minerals, and has been doing so for the past 50,000 years [Kelemen et al., 2011]. Our reaction path modeling of this system shows that the natural process is limited by subsurface availability of dissolved inorganic carbon, and that the rate of CO2 mineralization could be enhanced by a factor of 16,000 by injecting CO2 into the peridotite aquifer at 2 km depth and a fugacity of 100 bars. Injecting CO2 into mafic or ultramafic rock formations has been presumed difficult, as fractured crystalline rocks typically have low porosity and permeability; however these factors have yet to be comprehensively studied. To determine the actual value of these hydrogeological factors, this winter we carried out a multifaceted study of deep boreholes (up to 350m) in the mantle peridotite and the Moho transition zone of the Samail Ophiolite. A suite of physical and chemical parameters were collected, including slug tests for hydraulic conductivity, geophysical well logs for porosity and hydraulic conductivity, drill chips for extent and composition of secondary mineralization, and water and dissolved gas samples for chemical composition. All of these factors combine to provide a comprehensive look at the chemical and physical processes underlying natural mineral carbonation in mantle peridotites. Understanding the natural process is critical, as mineral carbonation in ultramafic rocks is being explored as a permanent and relatively safe option for geologic carbon sequestration. While injectivity in these ultramafic formations was believed to be low, our slug test and geophysical well log data suggest that the hydraulic conductivity of fractured peridotites can actually be fairly high - up to

  11. DUAL PHASE MEMBRANE FOR HIGH TEMPERATURE CO2 SEPARATION

    SciTech Connect

    Jerry Y.S. Lin; Seungjoon Chung; Matthew Anderson

    2005-12-01

    This project is intended to expand upon the previous year's research en route to the development of a sustainable dual phase membrane for CO{sub 2} separation. It was found that the pores within the supports had to be less than 9 {micro}m in order to maintain the stability of the dual phase membrane. Pores larger than 9 {micro}m would be unable to hold the molten carbonate phase in place, rendering the membrane ineffective. Calculations show that 80% of the pore volume of the 0.5 media grade metal support was filled with the molten carbonate. Information obtained from EDS and SEM confirmed that the molten carbonate completely infiltrated the pores on both the contact and non-contact size of the metal support. Permeation tests for CO{sub 2} and N{sub 2} at 450-750 C show very low permeance of those two gases through the dual phase membrane, which was expected due to the lack of ionization of those two gases. Permeance of the CO{sub 2} and O{sub 2} mixture was much higher, indicating that the gases do form an ionic species, CO{sub 3}{sup 2-}, enhancing transport through the membrane. However, at temperatures in excess of 650 C, the permeance of CO{sub 3}{sup 2-} decreased quite rapidly, while predictions showed that permeance should have continued to increase. XRD data obtained form the surface of the membrane indicated the formation of lithium iron oxides on the support. This layer has a very low conductivity, which drastically reduces the flow of electrons to the CO{sub 2}/O{sub 2} gas mixture, limiting the formation of the ionic species. These results indicate that the use of stainless steel supports in a high temperature oxidative environment can lead to decreased performance of the membranes. This revelation has created the need for an oxidation resistant support, which can be gained by the use of a ceramic-type membrane. Future research efforts will be directed towards preparation of a new ceramic-carbonate dual phase membrane. The membrane will based on an

  12. Dual Phase Membrane for High temperature CO2 Separation

    SciTech Connect

    Jerry Y.S. Lin; Matthew Anderson

    2005-12-01

    Research in the previous years in this project found that stainless steel supports are oxidized during high temperature, dual phase membrane separation of carbon dioxide (with oxygen). Consequently, a new material has been sought to alleviate the problems with oxidation. Lanthanum cobaltite oxide is a suitable candidate for the support material in the dual phase membrane due to its oxidation resistance and electronic conductivity. Porous lanthanum cobaltite membranes were prepared via the citrate method, using nitrate metal precursors as the source of La, Sr, Co and Fe. The material was prepared and ground into a powder, which was subsequently pressed into disks for sintering at 900 C. Conductivity measurements were evaluated using the four-probe DC method. Support pore size was determined by helium permeation. Conductivity of the lanthanum cobaltite material was found to be at a maximum of 0.1856 S/cm at 550 C. The helium permeance of the lanthanum cobaltite membranes for this research was on the order of 10{sup -6} moles/m{sup 2} {center_dot} Pa {center_dot} s, proving that the membranes are porous after sintering at 900 C. The average pore size based on steady state helium permeance measurements was found to be between 0.37 and 0.57 {micro}m. The lanthanum cobaltite membranes have shown to have desired porosity, pore size and electric conductivity as the support for the dual-phase membranes. Molten carbonate was infiltrated to the pores of lanthanum cobaltite membranes support. After infiltration with molten carbonate, the helium permeance of the membranes decreased by three orders of magnitude to 10{sup -9} moles/m{sup 2} {center_dot} Pa {center_dot} s. This number, however, is one order of magnitude larger than the room temperate permeance of the stainless steel supports after infiltration with molten carbonate. Optimization of the dip coating process with molten carbonate will be evaluated to determine if lower permeance values can be obtained with the

  13. CO2 hydrate formation and dissociation in cooled porous media: a potential technology for CO2 capture and storage.

    PubMed

    Yang, Mingjun; Song, Yongchen; Jiang, Lanlan; Zhu, Ningjun; Liu, Yu; Zhao, Yuechao; Dou, Binlin; Li, Qingping

    2013-09-01

    The purpose of this study was to investigate the hydrate formation and dissociation with CO2 flowing through cooled porous media at different flow rates, pressures, temperatures, and flow directions. CO2 hydrate saturation was quantified using the mean intensity of water. The experimental results showed that the hydrate block appeared frequently, and it could be avoided by stopping CO2 flooding early. Hydrate formed rapidly as the temperature was set to 274.15 or 275.15 K, but the hydrate formation delayed when it was 276.15 K. The flow rate was an important parameter for hydrate formation; a too high or too low rate was not suitable for CO2 hydration formation. A low operating pressure was also unacceptable. The gravity made hydrate form easily in the vertically upward flow direction. The pore water of the second cycle converted to hydrate more completely than that of the first cycle, which was a proof of the hydrate "memory effect". When the pressure was equal to atmospheric pressure, hydrate did not dissociate rapidly and abundantly, and a long time or reduplicate depressurization should be used in industrial application. PMID:23915205

  14. The CarbFix Pilot Project in Iceland - CO2 capture and mineral storage in basaltic rocks

    NASA Astrophysics Data System (ADS)

    Sigurdardottir, H.; Sigfusson, B.; Aradottir, E. S.; Gunnlaugsson, E.; Gislason, S. R.; Alfredsson, H. A.; Broecker, W. S.; Matter, J. M.; Stute, M.; Oelkers, E.

    2010-12-01

    The overall objective of the CarbFix project is to develop and optimize a practical and cost-effective technology for capturing CO2 and storing it via in situ mineral carbonation in basaltic rocks, as well as to train young scientist to carry the corresponding knowledge into the future. The project consists of a field injection of CO2 charged water at the Hellisheidi geothermal power plant in SW Iceland, laboratory experiments, numerical reactive transport modeling, tracer tests, natural analogue and cost analysis. The CO2 injection site is situated about 3 km south of the Hellisheidi geothermal power plant. Reykjavik Energy operates the power plant, which currently produces 60,000 tons/year CO2 of magmatic origin. The produced geothermal gas mainly consists of CO2 and H2S. The two gases will be separated in a pilot gas treatment plant, and CO2 will be transported in a pipeline to the injection site. There, CO2 will be fully dissolved in 20 - 25°C water during injection at 25 - 30 bar pressure, resulting in a single fluid phase entering the storage formation, which consists of relatively fresh basaltic lavas. The CO2 charged water is reactive and will dissolve divalent cations from the rock, which will combine with the dissolved carbon to form solid thermodynamically stable carbonate minerals. The injection test is designed to inject 2200 tons of CO2 per year. In the past three years the CarbFix project has been addressing background fluid chemistries at the injection site and characterizing the target reservoir for the planned CO2 injection. Numerous groundwater samples have been collected and analysed. A monitoring and accounting plan has been developed, which integrates surface, subsurface and atmospheric monitoring. A weather station is operating at the injection site for continuous monitoring of atmospheric CO2 and to track all key parameters for the injection. Environmental authorities have granted licenses for the CO2 injection and the use of tracers, based

  15. Iron phthalocyanine modified mesoporous titania nanoparticles for photocatalytic activity and CO2 capture applications.

    PubMed

    Ramacharyulu, P V R K; Muhammad, Raeesh; Praveen Kumar, J; Prasad, G K; Mohanty, Paritosh

    2015-10-21

    An iron(II)phthalocyanine (Fepc) modified mesoporous titania (Fepc-TiO2) nanocatalyst with a specific surface area of 215 m(2) g(-1) has been synthesized by a hydrothermal method. Fepc-TiO2 degrades one of the highly toxic chemical warfare agents, sulfur mustard (SM), photocatalytically under sunlight with an exposure time of as low as 70 min. Furthermore, the mesoporous Fepc-TiO2 also captured 2.1 mmol g(-1) of CO2 at 273 K and 1 atm. PMID:26393761

  16. The incorporation of graphene oxide into polysulfone mixed matrix membrane for CO2/CH4 separation

    NASA Astrophysics Data System (ADS)

    Zahri, K.; Goh, P. S.; Ismail, A. F.

    2016-06-01

    Carbon dioxide (CO2) is often found as the main impurity in natural gas, where methane (CH4) is the major component. The presence of CO2 in natural gas leads to several problems such as reducing the energy content of natural gas and cause pipeline corrosion. Thus it must be removed to meet specifications (CO2 ≤ 2 mol%) before the gas can be delivered to the pipeline. In this work, hollow fiber mixed matrix membrane (MMM) were fabricated by embedding graphene oxide (GO) into a polysulfone (PSf) polymer matrix to improve membrane properties as well as its separation performance towards CO2/CH4 gas. The membrane properties were investigated for pristine membrane and mixed matrix membrane filled with filler loading of 0.25%. The synthesized GO and properties of fabricated membranes were characterized and studied using TEM, AFM, XRD, FTIR and SEM respectively. The permeance of pure gases and ideal selectivity of CO2/CH4 gas were determined using pure gas permeation experiment. GO has affinity towards CO2 gas. The nanosheet structure creates path for small molecule gas and restricted large molecule gas to pass through the membrane. The incorporation of GO in PSf polymer enhanced the permeance of CO 2 and CO2/CH4 separation from 64.47 to 86.80 GPU and from 19 to 25 respectively.

  17. Jumpstarting commercial-scale CO2 capture and storage with ethylene production and enhanced oil recovery in the US Gulf

    DOE PAGESBeta

    Middleton, Richard S.; Levine, Jonathan S.; Bielicki, Jeffrey M.; Viswanathan, Hari S.; Carey, J. William; Stauffer, Philip H.

    2015-04-27

    CO2 capture, utilization, and storage (CCUS) technology has yet to be widely deployed at a commercial scale despite multiple high-profile demonstration projects. We suggest that developing a large-scale, visible, and financially viable CCUS network could potentially overcome many barriers to deployment and jumpstart commercial-scale CCUS. To date, substantial effort has focused on technology development to reduce the costs of CO2 capture from coal-fired power plants. Here, we propose that near-term investment could focus on implementing CO2 capture on facilities that produce high-value chemicals/products. These facilities can absorb the expected impact of the marginal increase in the cost of production onmore » the price of their product, due to the addition of CO2 capture, more than coal-fired power plants. A financially viable demonstration of a large-scale CCUS network requires offsetting the costs of CO2 capture by using the CO2 as an input to the production of market-viable products. As a result, we demonstrate this alternative development path with the example of an integrated CCUS system where CO2 is captured from ethylene producers and used for enhanced oil recovery in the U.S. Gulf Coast region.« less

  18. Efficient CO2 Capture by Porous, Nitrogen-Doped Carbonaceous Adsorbents Derived from Task-Specific Ionic Liquids

    SciTech Connect

    Zhu, X; Hillesheim, PC; Mahurin, SM; Wang, CM; Tian, CC; Brown, S; Luo, HM; Veith, GM; Han, KS; Hagaman, EW; Liu, HL; Dai, S

    2012-08-21

    The search for a better carbon dioxide (CO2) capture material is attracting significant attention because of an increase in anthropogenic emissions. Porous materials are considered to be among the most promising candidates. A series of porous, nitrogen-doped carbons for CO2 capture have been developed by using high-yield carbonization reactions from task-specific ionic liquid (TSIL) precursors. Owing to strong interactions between the CO2 molecules and nitrogen-containing basic sites within the carbon framework, the porous nitrogen-doped compound derived from the carbonization of a TSIL at 500 degrees C, CN500, exhibits an exceptional CO2 absorption capacity of 193 mg of CO2 per g sorbent (4.39 mmol g(-1) at 0 degrees C and 1 bar), which demonstrates a significantly higher capacity than previously reported adsorbents. The application of TSILs as precursors for porous materials provides a new avenue for the development of improved materials for carbon capture.

  19. BioCO2 - a multidisciplinary, biological approach using solar energy to capture CO2 while producing H2 and high value products.

    PubMed

    Skjånes, Kari; Lindblad, Peter; Muller, Jiri

    2007-10-01

    Many areas of algae technology have developed over the last decades, and there is an established market for products derived from algae, dominated by health food and aquaculture. In addition, the interest for active biomolecules from algae is increasing rapidly. The need for CO(2) management, in particular capture and storage is currently an important technological, economical and global political issue and will continue to be so until alternative energy sources and energy carriers diminish the need for fossil fuels. This review summarizes in an integrated manner different technologies for use of algae, demonstrating the possibility of combining different areas of algae technology to capture CO(2) and using the obtained algal biomass for various industrial applications thus bringing added value to the capturing and storage processes. Furthermore, we emphasize the use of algae in a novel biological process which produces H(2) directly from solar energy in contrast to the conventional CO(2) neutral biological methods. This biological process is a part of the proposed integrated CO(2) management scheme. PMID:17662653

  20. Tandem Mass Spectrometry Measurement of the Collision Products of Carbamate Anions Derived from CO2 Capture Sorbents: Paving the Way for Accurate Quantitation

    NASA Astrophysics Data System (ADS)

    Jackson, Phil; Fisher, Keith J.; Attalla, Moetaz Ibrahim

    2011-08-01

    The reaction between CO2 and aqueous amines to produce a charged carbamate product plays a crucial role in post-combustion capture chemistry when primary and secondary amines are used. In this paper, we report the low energy negative-ion CID results for several anionic carbamates derived from primary and secondary amines commonly used as post-combustion capture solvents. The study was performed using the modern equivalent of a triple quadrupole instrument equipped with a T-wave collision cell. Deuterium labeling of 2-aminoethanol (1,1,2,2,-d4-2-aminoethanol) and computations at the M06-2X/6-311++G(d,p) level were used to confirm the identity of the fragmentation products for 2-hydroxyethylcarbamate (derived from 2-aminoethanol), in particular the ions CN-, NCO- and facile neutral losses of CO2 and water; there is precedent for the latter in condensed phase isocyanate chemistry. The fragmentations of 2-hydroxyethylcarbamate were generalized for carbamate anions derived from other capture amines, including ethylenediamine, diethanolamine, and piperazine. We also report unequivocal evidence for the existence of carbamate anions derived from sterically hindered amines ( Tris(2-hydroxymethyl)aminomethane and 2-methyl-2-aminopropanol). For the suite of carbamates investigated, diagnostic losses include the decarboxylation product (-CO2, 44 mass units), loss of 46 mass units and the fragments NCO- ( m/z 42) and CN- ( m/z 26). We also report low energy CID results for the dicarbamate dianion (-O2CNHC2H4NHCO{2/-}) commonly encountered in CO2 capture solution utilizing ethylenediamine. Finally, we demonstrate a promising ion chromatography-MS based procedure for the separation and quantitation of aqueous anionic carbamates, which is based on the reported CID findings. The availability of accurate quantitation methods for ionic CO2 capture products could lead to dynamic operational tuning of CO2 capture-plants and, thus, cost-savings via real-time manipulation of solvent

  1. Isotope separation by photoselective dissociative electron capture

    DOEpatents

    Stevens, Charles G. [Pleasanton, CA

    1978-08-29

    A method of separating isotopes based on photoselective electron capture dissociation of molecules having an electron capture cross section dependence on the vibrational state of the molecule. A molecular isotope source material is irradiated to selectively excite those molecules containing a desired isotope to a predetermined vibrational state having associated therewith an electron capture energy region substantially non-overlapping with the electron capture energy ranges associated with the lowest vibration states of the molecules. The isotope source is also subjected to electrons having an energy corresponding to the non-overlapping electron capture region whereby the selectively excited molecules preferentially capture electrons and dissociate into negative ions and neutrals. The desired isotope may be in the negative ion product or in the neutral product depending upon the mechanism of dissociation of the particular isotope source used. The dissociation product enriched in the desired isotope is then separated from the reaction system by conventional means. Specifically, .sup.235 UF.sub.6 is separated from a UF.sub.6 mixture by selective excitation followed by dissociative electron capture into .sup.235 UF.sub.5 - and F.

  2. Isotope separation by photoselective dissociative electron capture

    DOEpatents

    Stevens, C.G.

    1978-08-29

    Disclosed is a method of separating isotopes based on photoselective electron capture dissociation of molecules having an electron capture cross section dependence on the vibrational state of the molecule. A molecular isotope source material is irradiated to selectively excite those molecules containing a desired isotope to a predetermined vibrational state having associated therewith an electron capture energy region substantially non-overlapping with the electron capture energy ranges associated with the lowest vibration states of the molecules. The isotope source is also subjected to electrons having an energy corresponding to the non-overlapping electron capture region whereby the selectively excited molecules preferentially capture electrons and dissociate into negative ions and neutrals. The desired isotope may be in the negative ion product or in the neutral product depending upon the mechanism of dissociation of the particular isotope source used. The dissociation product enriched in the desired isotope is then separated from the reaction system by conventional means. Specifically, [sup 235]UF[sub 6] is separated from a UF[sub 6] mixture by selective excitation followed by dissociative electron capture into [sup 235]UF[sub 5]- and F. 2 figs.

  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. Technical and Energy Performance of an Advanced, Aqueous Ammonia-Based CO2 Capture Technology for a 500 MW Coal-Fired Power Station.

    PubMed

    Li, Kangkang; Yu, Hai; Feron, Paul; Tade, Moses; Wardhaugh, Leigh

    2015-08-18

    Using a rate-based model, we assessed the technical feasibility and energy performance of an advanced aqueous-ammonia-based postcombustion capture process integrated with a coal-fired power station. The capture process consists of three identical process trains in parallel, each containing a CO2 capture unit, an NH3 recycling unit, a water separation unit, and a CO2 compressor. A sensitivity study of important parameters, such as NH3 concentration, lean CO2 loading, and stripper pressure, was performed to minimize the energy consumption involved in the CO2 capture process. Process modifications of the rich-split process and the interheating process were investigated to further reduce the solvent regeneration energy. The integrated capture system was then evaluated in terms of the mass balance and the energy consumption of each unit. The results show that our advanced ammonia process is technically feasible and energy-competitive, with a low net power-plant efficiency penalty of 7.7%. PMID:26208135

  5. Mars Atmospheric Capture and Gas Separation

    NASA Technical Reports Server (NTRS)

    Muscatello, Anthony; Santiago-Maldonado, Edgardo; Gibson, Tracy; Devor, Robert; Captain, James

    2011-01-01

    The Mars atmospheric capture and gas separation project is selecting, developing, and demonstrating techniques to capture and purify Martian atmospheric gases for their utilization for the production of hydrocarbons, oxygen, and water in ISRU systems. Trace gases will be required to be separated from Martian atmospheric gases to provide pure C02 to processing elements. In addition, other Martian gases, such as nitrogen and argon, occur in concentrations high enough to be useful as buffer gas and should be captured as welL To achieve these goals, highly efficient gas separation processes will be required. These gas separation techniques are also required across various areas within the ISRU project to support various consumable production processes. The development of innovative gas separation techniques will evaluate the current state-of-the-art for the gas separation required, with the objective to demonstrate and develop light-weight, low-power methods for gas separation. Gas separation requirements include, but are not limited to the selective separation of: (1) methane and water from un-reacted carbon oxides (C02- CO) and hydrogen typical of a Sabatier-type process, (2) carbon oxides and water from unreacted hydrogen from a Reverse Water-Gas Shift process, (3) carbon oxides from oxygen from a trash/waste processing reaction, and (4) helium from hydrogen or oxygen from a propellant scavenging process. Potential technologies for the separations include freezers, selective membranes, selective solvents, polymeric sorbents, zeolites, and new technologies. This paper and presentation will summarize the results of an extensive literature review and laboratory evaluations of candidate technologies for the capture and separation of C02 and other relevant gases.

  6. Atomistic modeling of CO 2 capture in primary and tertiary amines - Heat of absorption and density changes

    NASA Astrophysics Data System (ADS)

    Maiti, A.; Bourcier, W. L.; Aines, R. D.

    2011-06-01

    With the aim of exploring new amine-based chemistry for CO 2 capture at large industrial scales we performed atomistic modeling of CO 2 chemisorption in aqueous solutions of primary and tertiary amines. DFT-based quantum chemical solvation calculations are shown to yield a number of important results, including the relative stability of ion species (carbamate vs. bicarbonate), heat of absorption, and density and volume changes as a function of CO 2 loading. Good agreement of simulation results with available experimental data provides confidence in the accuracy of such computational methods in predicting properties of new solvent systems and capture designs.

  7. 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

  8. Coordination effect-regulated CO2 capture with an alkali metal onium salts/crown ether system

    SciTech Connect

    Yang, Zhen-Zhen; Jiang, Deen; Zhu, Xiang; Tian, Chengcheng; Brown, Suree; Do-Thanh, Chi-Linh; He, Liang-Nian; Dai, Sheng

    2014-01-01

    A coordination effect was employed to realize equimolar CO2 absorption, adopting easily synthesized amino group containing absorbents (alkali metal onium salts). The essence of our strategy was to increase the steric hindrance of cations so as to enhance a carbamic acid pathway for CO2 capture. Our easily synthesized alkali metal amino acid salts or phenolates were coordinated with crown ethers, in which highly sterically hindered cations were obtained through a strong coordination effect of crown ethers with alkali metal cations. For example, a CO2 capacity of 0.99 was attained by potassium prolinate/18-crown-6, being characterized by NMR, FT-IR, and quantum chemistry calculations to go through a carbamic acid formation pathway. The captured CO2 can be stripped under very mild conditions (50 degrees C, N-2). Thus, this protocol offers an alternative for the development of technological innovation towards efficient and low energy processes for carbon capture and sequestration.

  9. Opportunities for Decarbonizing Existing U.S. Coal-Fired Power Plants via CO2 Capture, Utilization and Storage.

    PubMed

    Zhai, Haibo; Ou, Yang; Rubin, Edward S

    2015-07-01

    This study employs a power plant modeling tool to explore the feasibility of reducing unit-level emission rates of CO2 by 30% by retrofitting carbon capture, utilization, and storage (CCUS) to existing U.S. coal-fired electric generating units (EGUs). Our goal is to identify feasible EGUs and their key attributes. The results indicate that for about 60 gigawatts of the existing coal-fired capacity, the implementation of partial CO2 capture appears feasible, though its cost is highly dependent on the unit characteristics and fuel prices. Auxiliary gas-fired boilers can be employed to power a carbon capture process without significant increases in the cost of electricity generation. A complementary CO2 emission trading program can provide additional economic incentives for the deployment of CCS with 90% CO2 capture. Selling and utilizing the captured CO2 product for enhanced oil recovery can further accelerate CCUS deployment and also help reinforce a CO2 emission trading market. These efforts would allow existing coal-fired EGUs to continue to provide a significant share of the U.S. electricity demand. PMID:26023722

  10. Examination of the effect of system pressure ratio and heat recuperation on the efficiency of a coal based gas turbine fuel cell hybrid power generation system with CO2 capture

    SciTech Connect

    VanOsdol, J.G.; Gemmen, R.S.; Liese, E.A

    2008-06-01

    This paper examines two coal-based hybrid configurations that employ separated anode and cathode streams for the capture and compression of CO2. One configuration uses a standard Brayton cycle, and the other adds heat recuperation ahead of the fuel cell. Results show that peak efficiencies near 55% are possible, regardless of cycle configuration, including the cost in terms of energy production of CO2 capture and compression. The power that is required to capture and compress the CO2 is shown to be approximately 15% of the total plant power.

  11. Rapid and Accurate Machine Learning Recognition of High Performing Metal Organic Frameworks for CO2 Capture.

    PubMed

    Fernandez, Michael; Boyd, Peter G; Daff, Thomas D; Aghaji, Mohammad Zein; Woo, Tom K

    2014-09-01

    In this work, we have developed quantitative structure-property relationship (QSPR) models using advanced machine learning algorithms that can rapidly and accurately recognize high-performing metal organic framework (MOF) materials for CO2 capture. More specifically, QSPR classifiers have been developed that can, in a fraction of a section, identify candidate MOFs with enhanced CO2 adsorption capacity (>1 mmol/g at 0.15 bar and >4 mmol/g at 1 bar). The models were tested on a large set of 292 050 MOFs that were not part of the training set. The QSPR classifier could recover 945 of the top 1000 MOFs in the test set while flagging only 10% of the whole library for compute intensive screening. Thus, using the machine learning classifiers as part of a high-throughput screening protocol would result in an order of magnitude reduction in compute time and allow intractably large structure libraries and search spaces to be screened. PMID:26278259

  12. Luminescent Rhenium(I) Pyridyldiaminocarbene Complexes: Photophysics, Anion-Binding, and CO2-Capturing Properties.

    PubMed

    Ng, Chi-On; Cheng, Shun-Cheung; Chu, Wing-Kin; Tang, Kin-Man; Yiu, Shek-Man; Ko, Chi-Chiu

    2016-08-15

    A series of luminescent isocyanorhenium(I) complexes with chelating acyclic diaminocarbene ligands (N^C) has been synthesized and characterized. Two of these carbene complexes have also been structurally characterized by X-ray crystallography. These complexes show blue-to-red phosphorescence, with the emission maxima not only considerably varied with a change in the number of ancillary isocyanide ligands but also extremely sensitive to the electronic and steric nature of the substituents on the acyclic diaminocarbene ligand. A detailed study with the support of density functional theory calculations revealed that the lowest-energy absorption and phosphorescence of these complexes in a degassed CH2Cl2 solution are derived from the predominantly metal-to-ligand charge-transfer [dπ(Re) → π*(N^C)] excited state. The unprecedented anion-binding and CO2-capturing properties of the acyclic diaminocarbene have also been described. PMID:27458842

  13. Separating the influence of temperature, drought, and fire on interannual variability in atmospheric CO2

    PubMed Central

    Keppel-Aleks, Gretchen; Wolf, Aaron S; Mu, Mingquan; Doney, Scott C; Morton, Douglas C; Kasibhatla, Prasad S; Miller, John B; Dlugokencky, Edward J; Randerson, James T

    2014-01-01

    The response of the carbon cycle in prognostic Earth system models (ESMs) contributes significant uncertainty to projections of global climate change. Quantifying contributions of known drivers of interannual variability in the growth rate of atmospheric carbon dioxide (CO2) is important for improving the representation of terrestrial ecosystem processes in these ESMs. Several recent studies have identified the temperature dependence of tropical net ecosystem exchange (NEE) as a primary driver of this variability by analyzing a single, globally averaged time series of CO2 anomalies. Here we examined how the temporal evolution of CO2 in different latitude bands may be used to separate contributions from temperature stress, drought stress, and fire emissions to CO2 variability. We developed atmospheric CO2 patterns from each of these mechanisms during 1997–2011 using an atmospheric transport model. NEE responses to temperature, NEE responses to drought, and fire emissions all contributed significantly to CO2 variability in each latitude band, suggesting that no single mechanism was the dominant driver. We found that the sum of drought and fire contributions to CO2 variability exceeded direct NEE responses to temperature in both the Northern and Southern Hemispheres. Additional sensitivity tests revealed that these contributions are masked by temporal and spatial smoothing of CO2 observations. Accounting for fires, the sensitivity of tropical NEE to temperature stress decreased by 25% to 2.9 ± 0.4 Pg C yr−1 K−1. These results underscore the need for accurate attribution of the drivers of CO2 variability prior to using contemporary observations to constrain long-term ESM responses. PMID:26074665

  14. Ex Situ CO2 capture by carbonation of steelmaking slag coupled with metalworking wastewater in a rotating packed bed.

    PubMed

    Pan, Shu-Yuan; Chiang, Pen-Chi; Chen, Yi-Hung; Tan, Chung-Sung; Chang, E-E

    2013-04-01

    Both basic oxygen furnace (BOF) slag and cold-rolling wastewater (CRW) exhibiting highly alkaline characteristics require stabilization and neutralization prior to utilization and/or final disposal. Using CO2 from flue gases as the stabilizing and neutralizing agents could also diminish CO2 emissions. In this investigation, ex situ hot stove gas containing 30 vol% CO2 in the steelmaking process was captured by accelerated carbonation of BOF slag coupled with CRW in a rotating packed bed (RPB). The developed RPB process exhibits superior results, with significant CO2 removal efficiency (η) of 96-99% in flue gas achieved within a short reaction time of 1 min at 25 °C and 1 atm. Calcite (CaCO3) was identified as the main product according to XRD and SEM-XEDS observations. In addition, the elimination of lime and Ca(OH)2 in the BOF slag during carbonation is beneficial to its further use as construction material. Consequently, the developed RPB process could capture the CO2 from the flue gas, neutralize the CRW, and demonstrate the utilization potential for BOF slag. It was also concluded that carbonation of BOF slag coupled with CRW in an RPB is a viable method for CO2 capture due to its higher mass transfer rate and CO2 removal efficiency in a short reaction time. PMID:23458276

  15. Effects of Microporosity and Surface Chemistry on Separation Performances of N-Containing Pitch-Based Activated Carbons for CO2/N2 Binary Mixture

    NASA Astrophysics Data System (ADS)

    Lee, Min-Sang; Park, Mira; Kim, Hak Yong; Park, Soo-Jin

    2016-03-01

    In this study, N-containing pitch-based activated carbons (NPCs) were prepared using petroleum pitch with a low softening point and melamine with a high nitrogen content. The major advantage of the preparation method is that it enables variations in chemical structures and textural properties by steam activation at high temperatures. The adequate micropore structures, appropriate chemical modifications, and high adsorption enthalpies of NPCs are favorable for CO2 adsorption onto carbon surfaces. Furthermore, the structure generates a considerable gas/N-containing carbon interfacial area, and provides selective access to CO2 molecules over N2 molecules by offering an increased number of active sites on the carbon surfaces. The highest CO2/N2 selectivity, i.e., 47.5, and CO2 adsorption capacity for a CO2/N2 (0.15:0.85) binary gas mixture, i.e., 5.30 wt%, were attained at 298 K. The NPCs also gave reversible and durable CO2-capturing performances. All the results suggest that NPCs are promising CO2 sorbents, which can meet the challenges of current CO2 capture and separation techniques.

  16. Effects of Microporosity and Surface Chemistry on Separation Performances of N-Containing Pitch-Based Activated Carbons for CO2/N2 Binary Mixture

    PubMed Central

    Lee, Min-Sang; Park, Mira; Kim, Hak Yong; Park, Soo-Jin

    2016-01-01

    In this study, N-containing pitch-based activated carbons (NPCs) were prepared using petroleum pitch with a low softening point and melamine with a high nitrogen content. The major advantage of the preparation method is that it enables variations in chemical structures and textural properties by steam activation at high temperatures. The adequate micropore structures, appropriate chemical modifications, and high adsorption enthalpies of NPCs are favorable for CO2 adsorption onto carbon surfaces. Furthermore, the structure generates a considerable gas/N-containing carbon interfacial area, and provides selective access to CO2 molecules over N2 molecules by offering an increased number of active sites on the carbon surfaces. The highest CO2/N2 selectivity, i.e., 47.5, and CO2 adsorption capacity for a CO2/N2 (0.15:0.85) binary gas mixture, i.e., 5.30 wt%, were attained at 298 K. The NPCs also gave reversible and durable CO2-capturing performances. All the results suggest that NPCs are promising CO2 sorbents, which can meet the challenges of current CO2 capture and separation techniques. PMID:26987683

  17. Effects of Microporosity and Surface Chemistry on Separation Performances of N-Containing Pitch-Based Activated Carbons for CO2/N2 Binary Mixture.

    PubMed

    Lee, Min-Sang; Park, Mira; Kim, Hak Yong; Park, Soo-Jin

    2016-01-01

    In this study, N-containing pitch-based activated carbons (NPCs) were prepared using petroleum pitch with a low softening point and melamine with a high nitrogen content. The major advantage of the preparation method is that it enables variations in chemical structures and textural properties by steam activation at high temperatures. The adequate micropore structures, appropriate chemical modifications, and high adsorption enthalpies of NPCs are favorable for CO2 adsorption onto carbon surfaces. Furthermore, the structure generates a considerable gas/N-containing carbon interfacial area, and provides selective access to CO2 molecules over N2 molecules by offering an increased number of active sites on the carbon surfaces. The highest CO2/N2 selectivity, i.e., 47.5, and CO2 adsorption capacity for a CO2/N2 (0.15:0.85) binary gas mixture, i.e., 5.30 wt%, were attained at 298 K. The NPCs also gave reversible and durable CO2-capturing performances. All the results suggest that NPCs are promising CO2 sorbents, which can meet the challenges of current CO2 capture and separation techniques. PMID:26987683

  18. A Superacid-Catalyzed Synthesis of Porous Membranes Based on Triazine Frameworks for CO2 Separation

    SciTech Connect

    Zhu, X; Tian, CC; Mahurin, SM; Chai, SH; Wang, CM; Brown, S; Veith, GM; Luo, HM; Liu, HL; Dai, S

    2012-06-27

    A general strategy for the synthesis of porous, fluorescent, triazine-framework-based membranes with intrinsic porosity through an aromatic nitrile trimerization reaction is presented. The essence of this strategy lies in the use of a superacid to catalyze the cross-linking reaction efficiently at a low temperature, allowing porous polymer membrane architectures to be facilely derived. With fiinctionalized triazine units, the membrane exhibits an increased selectivity for membrane separation of CO2 over N-2. The good ideal CO2/N-2 selectivity of 29 +/- 2 was achieved with a CO2 permeability of 518 +/- 25 barrer. Through this general synthesis protocol, a new class of porous polymer membranes with tunable functionalities and porosities can be derived, significantly expanding the currently limited library of polymers with intrinsic microporosity for synthesizing functional membranes in separation, catalysis, and energy storage/conversion.

  19. Separation of biospheric and fossil fuel fluxes of CO2 by atmospheric inversion of CO2 and 14CO2 measurements: Observation System Simulations

    NASA Astrophysics Data System (ADS)

    Basu, Sourish; Bharat Miller, John; Lehman, Scott

    2016-05-01

    National annual total CO2 emissions from combustion of fossil fuels are likely known to within 5-10 % for most developed countries. However, uncertainties are inevitably larger (by unknown amounts) for emission estimates at regional and monthly scales, or for developing countries. Given recent international efforts to establish emission reduction targets, independent determination and verification of regional and national scale fossil fuel CO2 emissions are likely to become increasingly important. Here, we take advantage of the fact that precise measurements of 14C in CO2 provide a largely unbiased tracer for recently added fossil-fuel-derived CO2 in the atmosphere and present an atmospheric inversion technique to jointly assimilate observations of CO2 and 14CO2 in order to simultaneously estimate fossil fuel emissions and biospheric exchange fluxes of CO2. Using this method in a set of Observation System Simulation Experiments (OSSEs), we show that given the coverage of 14CO2 measurements available in 2010 (969 over North America, 1063 globally), we can recover the US national total fossil fuel emission to better than 1 % for the year and to within 5 % for most months. Increasing the number of 14CO2 observations to ˜ 5000 per year over North America, as recently recommended by the National Academy of Science (NAS) (Pacala et al., 2010), we recover monthly emissions to within 5 % for all months for the US as a whole and also for smaller, highly emissive regions over which the specified data coverage is relatively dense, such as for the New England states or the NY-NJ-PA tri-state area. This result suggests that, given continued improvement in state-of-the art transport models, a measurement program similar in scale to that recommended by the NAS can provide for independent verification of bottom-up inventories of fossil fuel CO2 at the regional and national scale. In addition, we show that the dual tracer inversion framework can detect and minimize biases in

  20. The mechanism of vapor phase hydration of calcium oxide: implications for CO2 capture.

    PubMed

    Kudłacz, Krzysztof; Rodriguez-Navarro, Carlos

    2014-10-21

    Lime-based sorbents are used for fuel- and flue-gas capture, thereby representing an economic and effective way to reduce CO2 emissions. Their use involves cyclic carbonation/calcination which results in a significant conversion reduction with increasing number of cycles. To reactivate spent CaO, vapor phase hydration is typically performed. However, little is known about the ultimate mechanism of such a hydration process. Here, we show that the vapor phase hydration of CaO formed after calcination of calcite (CaCO3) single crystals is a pseudomorphic, topotactic process, which progresses via an intermediate disordered phase prior to the final formation of oriented Ca(OH)2 nanocrystals. The strong structural control during this solid-state phase transition implies that the microstructural features of the CaO parent phase predetermine the final structural and physicochemical (reactivity and attrition) features of the product hydroxide. The higher molar volume of the product can create an impervious shell around unreacted CaO, thereby limiting the efficiency of the reactivation process. However, in the case of compact, sintered CaO structures, volume expansion cannot be accommodated in the reduced pore volume, and stress generation leads to pervasive cracking. This favors complete hydration but also detrimental attrition. Implications of these results in carbon capture and storage (CCS) are discussed. PMID:25233236

  1. Phase Separation Kinetics in Isopycnic Mixtures of H2O/CO2/Ethoxylated Alcohol Surfactants

    NASA Technical Reports Server (NTRS)

    Lesemann, Markus; Paulaitis, Michael E.; Kaler, Eric W.

    1999-01-01

    Ternary mixtures of H2O and CO2 with ethoxylated alcohol (C(sub i)E(sub j)) surfactants form three coexisting liquid phases at conditions where two of the phases have equal densities (isopycnic phases). Isopycnic phase behavior has been observed for mixtures containing C8E5, C10E6, and C12E6 surfactants, but not for those mixtures containing either C4E1 or C8E3 surfactants. Pressure-temperature (PT) projections for this three-phase equilibrium were determined for H2O/CO2/C8E5 and H2O/CO2/C10E6 mixtures at temperatures from approximately 25 to 33 C and pressures between 90 and 350 bar. Measurements of the microstructure in H2O/CO2/C12E6 mixtures as a function of temperature (25-31 C), pressure (63.1-90.7 bar), and CO2 composition (0-3.9 wt%) have also been carried out to show that while micellar structure remains essentially un-changed, critical concentration fluctuations increase as the phase boundary and plait point are approached. In this report, we present our first measurements of the kinetics of isopycnic phase separation for ternary mixtures of H2O/CO2/C8E5.

  2. CO2/H2 separation using a highly permeable polyurethane membrane: Molecular dynamics simulation

    NASA Astrophysics Data System (ADS)

    Azizi, Morteza; Mousavi, Seyyed Abbas

    2015-11-01

    In this study, Molecular Dynamics (MD) and Grand Canonical Monte Carlo (GCMC) simulations were conducted to investigate the diffusivity, solubility, and permeability of CO2, CO, H2, and H2O in a polyurethane membrane at three different temperatures. The characterization of the simulated structures was carried out using XRD, FFV, Tg and density calculation, and cavity size distribution. The obtained results were within the expectations reported data in the literature based on the experimental approach, indicating the authenticity of approached in this work. The results showed that the highest diffusivity and permeability coefficients were observed for H2; while the highest values of solubility coefficient were found for H2O and CO2 gases. The increase of operating temperature from 298 K to 318 K has a positive effect on the permeation of all gases and a corresponding negative effect on the selectivity of the gas pair CO2/H2. Also, the results vividly showed that CO2 and H2O gases have a profound affinity with hard phase of polyurethane, while H2 and CO were conversely adsorbed by soft one. Moreover, the enhancement of permeability and permselectivity of CO2/H2 pair confirmed using Robeson Upper-Bond graph showed its good capacity for CO2/H2 separation application.

  3. Large-Scale Screening of Zeolite Structures for CO2 Membrane Separations

    SciTech Connect

    Kim, JH; Abouelnasr, M; Lin, LC; Smit, B

    2013-05-22

    We have conducted large-scale screening of zeolite materials for CO2/CH4 and CO2/N-2 membrane separation applications using the free energy landscape of the guest molecules inside these porous materials. We show how advanced molecular simulations can be integrated with the design of a simple separation process to arrive at a metric to rank performance of over 87 000 different zeolite structures, including the known IZA zeolite structures. Our novel, efficient algorithm using graphics processing units can accurately characterize both the adsorption and diffusion properties of a given structure in just a few seconds and accordingly find a set of optimal structures for different desired purity of separated gases from a large database of porous materials in reasonable wall time. Our analysis reveals that the optimal structures for separations usually consist of channels with adsorption sites spread relatively uniformly across the entire channel such that they feature well-balanced CO2 adsorption and diffusion properties. Our screening also shows that the top structures in the predicted zeolite database outperform the best known zeolite by a factor of 4-7. Finally, we have identified a completely different optimal set of zeolite structures that are suitable for an inverse process, in which the CO2 is retained while CH4 or N-2 is passed through a membrane.

  4. Large-scale screening of zeolite structures for CO2 membrane separations.

    PubMed

    Kim, Jihan; Abouelnasr, Mahmoud; Lin, Li-Chiang; Smit, Berend

    2013-05-22

    We have conducted large-scale screening of zeolite materials for CO2/CH4 and CO2/N2 membrane separation applications using the free energy landscape of the guest molecules inside these porous materials. We show how advanced molecular simulations can be integrated with the design of a simple separation process to arrive at a metric to rank performance of over 87,000 different zeolite structures, including the known IZA zeolite structures. Our novel, efficient algorithm using graphics processing units can accurately characterize both the adsorption and diffusion properties of a given structure in just a few seconds and accordingly find a set of optimal structures for different desired purity of separated gases from a large database of porous materials in reasonable wall time. Our analysis reveals that the optimal structures for separations usually consist of channels with adsorption sites spread relatively uniformly across the entire channel such that they feature well-balanced CO2 adsorption and diffusion properties. Our screening also shows that the top structures in the predicted zeolite database outperform the best known zeolite by a factor of 4-7. Finally, we have identified a completely different optimal set of zeolite structures that are suitable for an inverse process, in which the CO2 is retained while CH4 or N2 is passed through a membrane. PMID:23654217

  5. Comparing post-combustion CO2 capture operation at retrofitted coal-fired power plants in the Texas and Great Britain electric grids

    NASA Astrophysics Data System (ADS)

    Cohen, Stuart M.; Chalmers, Hannah L.; Webber, Michael E.; King, Carey W.

    2011-04-01

    This work analyses the carbon dioxide (CO2) capture system operation within the Electric Reliability Council of Texas (ERCOT) and Great Britain (GB) electric grids using a previously developed first-order hourly electricity dispatch and pricing model. The grids are compared in their 2006 configuration with the addition of coal-based CO2 capture retrofits and emissions penalties from 0 to 100 US dollars per metric ton of CO2 (USD/tCO2). CO2 capture flexibility is investigated by comparing inflexible CO2 capture systems to flexible ones that can choose between full- and zero-load CO2 capture depending on which operating mode has lower costs or higher profits. Comparing these two grids is interesting because they have similar installed capacity and peak demand, and both are isolated electricity systems with competitive wholesale electricity markets. However, differences in capacity mix, demand patterns, and fuel markets produce diverging behaviours of CO2 capture at coal-fired power plants. Coal-fired facilities are primarily base load in ERCOT for a large range of CO2 prices but are comparably later in the dispatch order in GB and consequently often supply intermediate load. As a result, the ability to capture CO2 is more important for ensuring dispatch of coal-fired facilities in GB than in ERCOT when CO2 prices are high. In GB, higher overall coal prices mean that CO2 prices must be slightly higher than in ERCOT before the emissions savings of CO2 capture offset capture energy costs. However, once CO2 capture is economical, operating CO2 capture on half the coal fleet in each grid achieves greater emissions reductions in GB because the total coal-based capacity is 6 GW greater than in ERCOT. The market characteristics studied suggest greater opportunity for flexible CO2 capture to improve operating profits in ERCOT, but profit improvements can be offset by a flexibility cost penalty.

  6. Understanding the mechanism of CO2 capture by 1,3 di-substituted imidazolium acetate based ionic liquids.

    PubMed

    Mao, James X; Steckel, Janice A; Yan, Fangyong; Dhumal, Nilesh; Kim, Hyung; Damodaran, Krishnan

    2016-01-21

    Efficient CO2 capture by ionic liquids needs a thorough understanding of underlying mechanisms of the CO2 interaction with ionic liquids, especially when it involves chemisorption. In this work we have systematically investigated the mechanism of CO2 capture by 1,3 di-substituted imidazolium acetate ionic liquids using density functional theory. Solvent effects are analyzed using QM/MM and QM/QM approaches with the help of molecular dynamics simulations and ONIOM methods. The investigation of different stepwise mechanisms shows that CO2 could be involved in the first step of the reaction mechanism, also a new two-step mechanism is proposed. The final stabilization step is analyzed and pointed out to be responsible for important experimentally-observed features of the reaction. PMID:26687108

  7. Activity and stability of immobilized carbonic anhydrase for promoting CO2 absorption into a carbonate solution for post-combustion CO2 capture

    USGS Publications Warehouse

    Zhang, S.; Zhang, Z.; Lu, Y.; Rostam-Abadi, M.; Jones, A.

    2011-01-01

    An Integrated Vacuum Carbonate Absorption Process (IVCAP) currently under development could significantly reduce the energy consumed when capturing CO2 from the flue gases of coal-fired power plants. The biocatalyst carbonic anhydrase (CA) has been found to effectively promote the absorption of CO2 into the potassium carbonate solution that would be used in the IVCAP. Two CA enzymes were immobilized onto three selected support materials having different pore structures. The thermal stability of the immobilized CA enzymes was significantly greater than their free counterparts. For example, the immobilized enzymes retained at least 60% of their initial activities after 90days at 50??C compared to about 30% for their free counterparts under the same conditions. The immobilized CA also had significantly improved resistance to concentrations of sulfate (0.4M), nitrate (0.05M) and chloride (0.3M) typically found in flue gas scrubbing liquids than their free counterparts. ?? 2011 Elsevier Ltd.

  8. Imidazolium Ionic Liquids, Imidazolylidene Heterocyclic Carbenes, and Zeolitic Imidazolate Frameworks for CO2 Capture and Photochemical Reduction.

    PubMed

    Wang, Sibo; Wang, Xinchen

    2016-02-01

    Imidazolium ionic liquids (ILs), imidazolylidene N-heterocyclic carbenes (NHCs), and zeolitic imidazolate frameworks (ZIFs) are imidazolate motifs which have been extensively investigated for CO2 adsorption and conversion applications. Summarized in this minireview is the recent progress in the capture, activation, and photochemical reduction of CO2 with these three imidazolate building blocks, from homogeneous molecular entities (ILs and NHCs) to heterogeneous crystalline scaffolds (ZIFs). The developments and existing shortcomings of the imidazolate motifs for their use in CO2 utilizations is assessed, with more of focus on CO2 photoredox catalysis. The opportunities and challenges of imidazolate scaffolds for future advancement of CO2 photochemical conversion for artificial photosynthesis are discussed. PMID:26683833

  9. Compact, Lightweight Adsorber and Sabatier Reactor for CO2 Capture and Reduction for Consumable and Propellant Production

    NASA Technical Reports Server (NTRS)

    Junaedi, Christian; Hawley, Kyle; Walsh, Dennis; Roychoudhury, Subir; Busby, Stacy A.; Abney, Morgan B.; Perry, Jay L.; Knox, James C.

    2012-01-01

    The utilization of CO2 to produce (or recycle) life support consumables, such as O2 and H2O, and to generate propellant fuels is an important aspect of NASA's concept for future, long duration planetary exploration. One potential approach is to capture and use CO2 from the Martian atmosphere to generate the consumables and propellant fuels. Precision Combustion, Inc. (PCI), with support from NASA, continues to develop its regenerable adsorber technology for capturing CO2 from gaseous atmospheres (for cabin atmosphere revitalization and in-situ resource utilization applications) and its Sabatier reactor for converting CO2 to methane and water. Both technologies are based on PCI's Microlith(R) substrates and have been demonstrated to reduce size, weight, and power consumption during CO2 capture and methanation process. For adsorber applications, the Microlith substrates offer a unique resistive heating capability that shows potential for short regeneration time and reduced power requirements compared to conventional systems. For the Sabatier applications, the combination of the Microlith substrates and durable catalyst coating permits efficient CO2 methanation that favors high reactant conversion, high selectivity, and durability. Results from performance testing at various operating conditions will be presented. An effort to optimize the Sabatier reactor and to develop a bench-top Sabatier Development Unit (SDU) will be discussed.

  10. Carbon dioxide capture-related gas adsorption and separation in metal-organic frameworks

    SciTech Connect

    Li, JR; Ma, YG; McCarthy, MC; Sculley, J; Yu, JM; Jeong, HK; Balbuena, PB; Zhou, HC

    2011-08-01

    Reducing anthropogenic CO2 emission and lowering the concentration of greenhouse gases in the atmosphere has quickly become one of the most urgent environmental issues of our age. Carbon capture and storage (CCS) is one option for reducing these harmful CO2 emissions. While a variety of technologies and methods have been developed, the separation of CO2 from gas streams is still a critical issue. Apart from establishing new techniques, the exploration of capture materials with high separation performance and low capital cost are of paramount importance. Metal-organic frameworks (MOFs), a new class of crystalline porous materials constructed by metal-containing nodes bonded to organic bridging ligands hold great potential as adsorbents or membrane materials in gas separation. In this paper, we review the research progress (from experimental results to molecular simulations) in MOFs for CO2 adsorption, storage, and separations (adsorptive separation and membrane-based separation) that are directly related to CO2 capture. (C) 2011 Elsevier B.V. All rights reserved.