Science.gov

Sample records for organic compound removal

  1. Removal of volatile organic compounds from paper coatings

    NASA Astrophysics Data System (ADS)

    Meier, Dirk; Warnecke, Hans-Joachim; Pruess, Jan

    1997-08-01

    From the chemical point of view paper coatings are mainly polymer dispersions. Polymer dispersions are constituted in multitude fields, for example as dispersion coatings or adhesives. As far as no additional treatment is done, polymer materials as well as polymer agents contain non polymer, volatile organic components that may arise from: (1) incomplete polymerization of the applied monomers, (2) primary materials containing non polymerizable components, (3) undesirable side reactions during the synthesis. Requirements for the removal of volatile substances from polymer dispersion are given by several reasons: (1) low molecular substances deteriorate the product characteristics (viscosity, thermal stability and others), (2) in order to comply with legislative standards, volatile organic compounds have to be removed from dispersions, especially when applied to large surfaces (e.g. in surface refining in paper and leather industries as well as on coating). The removal of volatile organic compounds (deodorization) can be realized in continuous or discontinuous processes. In contrast to highly developed process technology, the process itself is not well understood, especially mass transport phenomena between the gas phase and the aqueous polymer dispersion are insufficiently and controversially discussed in the literature. Two processes, their advantages and disadvantages and the description by mathematical- mechanistic models are presented in this paper.

  2. Process for removing an organic compound from water

    DOEpatents

    Baker, Richard W.; Kaschemekat, Jurgen; Wijmans, Johannes G.; Kamaruddin, Henky D.

    1993-12-28

    A process for removing organic compounds from water is disclosed. The process involves gas stripping followed by membrane separation treatment of the stripping gas. The stripping step can be carried out using one or multiple gas strippers and using air or any other gas as stripping gas. The membrane separation step can be carried out using a single-stage membrane unit or a multistage unit. Apparatus for carrying out the process is also disclosed. The process is particularly suited for treatment of contaminated groundwater or industrial wastewater.

  3. Removal of volatile organic compounds (VOCs) using biofilters

    SciTech Connect

    Carriere, P.E.; Mohaghegh, S.D.; Madabhushi, B.S.

    1995-12-31

    One of the most significant air pollution control challenges being faced by the Federal and State agencies and the chemical process industries is the control of emissions of volatile organic compounds (VOCs). VOCs are discharged from process industries as major components of mixed organic wastes which contaminate the environment. Among these wastes, benzene, toluene, ethyl benzene and xylene are classified as major pollutants with high frequencies of occurrence on the EPA list of priority pollutants. Biofiltration, a recent air pollution control technology, is the removal and decomposition of contaminants present in emissions of non hazardous substances using a biologically activated medium. Biofiltration involves contacting the contaminated emission gas stream with microorganisms in a filter media. Biofiltration utilizes microorganisms immobilized in the form of a biofilm layer on an adsorptive filter media. Compared to other technologies, biofiltration is inexpensive, reliable and requires no post treatment. The main objective of this study was to compare the performance of both Granular Activated Carbon (GAC) and Biologically Activated Carbon (BAC) for the removal of benzene and toluene.

  4. Remove volatile organic compounds (VOCs) with membrane separation techniques.

    PubMed

    Zhang, Lin; Weng, Huan-xin; Chen, Huan-lin; Gao, Cong-jie

    2002-04-01

    Membrane separation, a new technology for removing VOCs including pervaporation, vapor permeation, membrane contactor, and membrane bioreactor was presented. Comparing with traditional techniques, these special techniques are an efficient and energy-saving technology. Vapor permeation can be applied to recovery of organic solvents from exhaust streams. Membrane contactor could be used for removing or recovering VOCs from air or wastewater. Pervaporation and vapor permeation are viable methods for removing VOCs from wastewater to yield a VOC concentrate which could either be destroyed by conventional means, or be recycled for reuse.

  5. Removal of organic pollutants by surfactant modified zeolite: comparison between ionizable phenolic compounds and non-ionizable organic compounds.

    PubMed

    Xie, Jie; Meng, Wenna; Wu, Deyi; Zhang, Zhenjia; Kong, Hainan

    2012-09-15

    The aim of this study was to examine the adsorption capability and mechanism of hexadecyltrimethylammonium modified zeolite, which was synthesized from coal fly ash, for the removal of ionizable phenolic compounds (phenol, p-chlorophenol and bisphenol A, with different pK(a)) and non-ionizable organic compounds (aniline, nitrobenzene, and naphthalene, with different hydrophobicity). The obtained zeolite was identified as type Na-P1 (Na(6)Al(6)Si(10)O(32)·12H(2)O, JCPDS code 39-0219), which is classified into the gismondine group with a pore size of 3.1 Å × 4.5 Å [100] and 2.8 Å × 4.8 Å [101]. The adsorption of the two kinds of organic compounds was due to loaded surfactant bilayer because modified zeolite showed great ability for the removal of organic chemicals while little adsorption by zeolite was observed. The isotherm data of ionizable compounds fitted well to the Langmuir model but those of non-ionizable chemicals followed a linear equation. Uptake of ionizable compounds depended greatly on pH, increasing at alkaline pH conditions. In contrary, adsorption of non-ionizable chemicals was essentially the same at all pH levels studied. The adsorption of both kinds of organic compounds correlated well to k(ow) value, suggesting that more hydrophobic organic contaminants are more easily retained by modified zeolite. Based on the different adsorption behavior, the uptake of non-ionizable pollutants was thought to be a single partitioning process into the surfactant bilayer. For ionizable compounds, however, interaction of the phenol group(s) with the positively charged "head" of surfactant additionally functions.

  6. Precipitate hydrolysis process for the removal of organic compounds from nuclear waste slurries

    DOEpatents

    Doherty, J.P.; Marek, J.C.

    1987-02-25

    A process for removing organic compounds from a nuclear waste slurry comprising reacting a mixture of radioactive waste precipitate slurry and an acid in the presence of a catalytically effective amount of a copper(II) catalyst whereby the organic compounds in the precipitate slurry are hydrolyzed to form volatile organic compounds which are separated from the reacting mixture. The resulting waste slurry, containing less than 10 percent of the original organic compounds, is subsequently blended with high level radioactive sludge land transferred to a vitrification facility for processing into borosilicate glass for long-term storage. 2 figs., 3 tabs.

  7. Precipitate hydrolysis process for the removal of organic compounds from nuclear waste slurries

    DOEpatents

    Doherty, Joseph P.; Marek, James C.

    1989-01-01

    A process for removing organic compounds from a nuclear waste slurry comprising reacting a mixture of radioactive waste precipitate slurry and an acid in the presence of a catalytically effective amount of a copper (II) catalyst whereby the organic compounds in the precipitate slurry are hydrolyzed to form volatile organic compounds which are separated from the reacting mixture. The resulting waste slurry, containing less than 10 percent of the orginal organic compounds, is subsequently blended with high level radioactive sludge and transferred to a virtrification facility for processing into borosilicate glass for long-term storage.

  8. Composites for removing metals and volatile organic compounds and method thereof

    DOEpatents

    Coronado, Paul R.; Coleman, Sabre J.; Reynolds, John G.

    2006-12-12

    Functionalized hydrophobic aerogel/solid support structure composites have been developed to remove metals and organic compounds from aqueous and vapor media. The targeted metals and organics are removed by passing the aqueous or vapor phase through the composite which can be in molded, granular, or powder form. The composites adsorb the metals and the organics leaving a purified aqueous or vapor stream. The species-specific adsorption occurs through specific functionalization of the aerogels tailored towards specific metals and/or organics. After adsorption, the composites can be disposed of or the targeted metals and/or organics can be reclaimed or removed and the composites recycled.

  9. A novel membrane distillation-thermophilic bioreactor system: biological stability and trace organic compound removal.

    PubMed

    Wijekoon, Kaushalya C; Hai, Faisal I; Kang, Jinguo; Price, William E; Guo, Wenshan; Ngo, Hao H; Cath, Tzahi Y; Nghiem, Long D

    2014-05-01

    The removal of trace organic compounds (TrOCs) by a novel membrane distillation-thermophilic bioreactor (MDBR) system was examined. Salinity build-up and the thermophilic conditions to some extent adversely impacted the performance of the bioreactor, particularly the removal of total nitrogen and recalcitrant TrOCs. While most TrOCs were well removed by the thermophilic bioreactor, compounds containing electron withdrawing functional groups in their molecular structure were recalcitrant to biological treatment and their removal efficiency by the thermophilic bioreactor was low (0-53%). However, the overall performance of the novel MDBR system with respect to the removal of total organic carbon, total nitrogen, and TrOCs was high and was not significantly affected by the conditions of the bioreactor. All TrOCs investigated here were highly removed (>95%) by the MDBR system. Biodegradation, sludge adsorption, and rejection by MD contribute to the removal of TrOCs by MDBR treatment.

  10. Post-refining removal of organic nitrogen compounds from diesel fuels to improve environmental quality.

    PubMed

    Mushrush, George W; Quintana, Marian A; Bauserman, Joy W; Willauer, Heather D

    2011-01-01

    The purpose of this investigation was to remove the organic nitrogen compounds from petroleum-derived diesel fuels. These nitrogen compounds can cause environmental problems, as well as fuel instability problems that can degrade fuels and affect engine performance. Fuels were treated with two different filtering media, activated clay and silica tel. The methylene chloride extracts from both the activated clay and silica gel were subjected to GC/MS analysis. Close to 99% of the total organic nitrogen compounds were removed. About 60% of the nitrogen compounds identified consisted of pyridines, quinolines and tetra-hydroquinolines made up 26%, while indoles and carbazoles about 10% of the total nitrogen compounds. Of the nitrogen heterocyclics identified, indoles and carbazoles were linked to fuel instability reactions. The proposed method was tested on diesels fuels from a variety of countries and found to remove between 97.8 and 99.9% of the N-compounds. The results of this study showed that both of these filtering materials were effective in removing the organic nitrogen compounds and resulted in fuels that exhibited excellent storage stability. These simple filtering methods can be independent of the refining process and do result in an environmentally cleaner burning fuel.

  11. Efficiency of conventional drinking-water-treatment processes in removal of pharmaceuticals and other organic compounds.

    PubMed

    Stackelberg, Paul E; Gibs, Jacob; Furlong, Edward T; Meyer, Michael T; Zaugg, Steven D; Lippincott, R Lee

    2007-05-15

    Samples of water and sediment from a conventional drinking-water-treatment (DWT) plant were analyzed for 113 organic compounds (OCs) that included pharmaceuticals, detergent degradates, flame retardants and plasticizers, polycyclic aromatic hydrocarbons (PAHs), fragrances and flavorants, pesticides and an insect repellent, and plant and animal steroids. 45 of these compounds were detected in samples of source water and 34 were detected in samples of settled sludge and (or) filter-backwash sediments. The average percent removal of these compounds was calculated from their average concentration in time-composited water samples collected after clarification, disinfection (chlorination), and granular-activated-carbon (GAC) filtration. In general, GAC filtration accounted for 53% of the removal of these compounds from the aqueous phase; disinfection accounted for 32%, and clarification accounted for 15%. The effectiveness of these treatments varied widely within and among classes of compounds; some hydrophobic compounds were strongly oxidized by free chlorine, and some hydrophilic compounds were partly removed through adsorption processes. The detection of 21 of the compounds in 1 or more samples of finished water, and of 3 to 13 compounds in every finished-water sample, indicates substantial but incomplete degradation or removal of OCs through the conventional DWT process used at this plant.

  12. Efficiency of conventional drinking-water-treatment processes in removal of pharmaceuticals and other organic compounds

    USGS Publications Warehouse

    Stackelberg, P.E.; Gibs, J.; Furlong, E.T.; Meyer, M.T.; Zaugg, S.D.; Lippincott, R.L.

    2007-01-01

    Samples of water and sediment from a conventional drinking-water-treatment (DWT) plant were analyzed for 113 organic compounds (OCs) that included pharmaceuticals, detergent degradates, flame retardants and plasticizers, polycyclic aromatic hydrocarbons (PAHs), fragrances and flavorants, pesticides and an insect repellent, and plant and animal steroids. 45 of these compounds were detected in samples of source water and 34 were detected in samples of settled sludge and (or) filter-backwash sediments. The average percent removal of these compounds was calculated from their average concentration in time-composited water samples collected after clarification, disinfection (chlorination), and granular-activated-carbon (GAC) filtration. In general, GAC filtration accounted for 53% of the removal of these compounds from the aqueous phase; disinfection accounted for 32%, and clarification accounted for 15%. The effectiveness of these treatments varied widely within and among classes of compounds; some hydrophobic compounds were strongly oxidized by free chlorine, and some hydrophilic compounds were partly removed through adsorption processes. The detection of 21 of the compounds in 1 or more samples of finished water, and of 3 to 13 compounds in every finished-water sample, indicates substantial but incomplete degradation or removal of OCs through the conventional DWT process used at this plant. ?? 2007 Elsevier B.V. All rights reserved.

  13. OPTIMIZATION OF MULTICOMPONENT PERVAPORATION FOR REMOVAL OF VOLATILE ORGANIC COMPOUNDS FROM WATER

    EPA Science Inventory

    Optimal operation of a hollow fiber membrane module for pervaporative removal of multicomponent volatile organic compounds (VOCs) from wastewater was studied. A shell-and-tube heat-exchange type of hollow fiber module was considered for treatment of a wastewater containing toluen...

  14. OPTIMIZATION OF MULTICOMPONENT PERVAPORATION FOR REMOVAL OF VOLATILE ORGANIC COMPOUNDS FROM WATER

    EPA Science Inventory

    Optimal operation of a hollow fiber membrane module for pervaporative removal of multicomponent volatile organic compounds (VOCs) from wastewater was studied. A shell-and-tube heat-exchange type of hollow fiber module was considered for treatment of a wastewater containing toluen...

  15. Simultaneous removal of inorganic and organic compounds in wastewater by freshwater green microalgae.

    PubMed

    Zhou, Guang-Jie; Ying, Guang-Guo; Liu, Shan; Zhou, Li-Jun; Chen, Zhi-Feng; Peng, Fu-Qiang

    2014-08-01

    Batch experiments were carried out for 7 days to investigate the simultaneous removal of various organic and inorganic contaminants including total nitrogen (TN), total phosphorus (TP), metals, pharmaceuticals and personal care products (PPCPs), endocrine disrupting chemicals (EDCs), and estrogenic activity in wastewater by four freshwater green microalgae species, Chlamydomonas reinhardtii, Scenedesmus obliquus, Chlorella pyrenoidosa and Chlorella vulgaris. After treatment for 7 days, 76.7-92.3% of TN, and 67.5-82.2% of TP were removed by these four algae species. The removal of metals from wastewater by the four algae species varied among the metal species. These four algae species could remove most of the metals efficiently (>40% removal), but showed low efficiencies in removing Pb, Ni and Co. The four algae species were also found to be efficient in removing most of the selected organic compounds with >50% removal, and the estrogenic activity with removal efficiencies ranging from 46.2 to 81.1% from the wastewater. Therefore, algae could be harnessed to simultaneously remove various contaminants in wastewater.

  16. Removal of Indoor Volatile Organic Compounds via Photocatalytic Oxidation: A Short Review and Prospect.

    PubMed

    Huang, Yu; Ho, Steven Sai Hang; Lu, Yanfeng; Niu, Ruiyuan; Xu, Lifeng; Cao, Junji; Lee, Shuncheng

    2016-01-04

    Volatile organic compounds (VOCs) are ubiquitous in indoor environments. Inhalation of VOCs can cause irritation, difficulty breathing, and nausea, and damage the central nervous system as well as other organs. Formaldehyde is a particularly important VOC as it is even a carcinogen. Removal of VOCs is thus critical to control indoor air quality (IAQ). Photocatalytic oxidation has demonstrated feasibility to remove toxic VOCs and formaldehyde from indoor environments. The technique is highly-chemical stable, inexpensive, non-toxic, and capable of removing a wide variety of organics under light irradiation. In this paper, we review and summarize the traditional air cleaning methods and current photocatalytic oxidation approaches in both of VOCs and formaldehyde degradation in indoor environments. Influencing factors such as temperature, relative humidity, deactivation and reactivations of the photocatalyst are discussed. Aspects of the application of the photocatalytic technique to improve the IAQ are suggested.

  17. Removal of organic compounds during treating printing and dyeing wastewater of different process units.

    PubMed

    Wang, J; Long, M C; Zhang, Z J; Chi, L N; Qiao, X L; Zhu, H X; Zhang, Z F

    2008-03-01

    Wastewater in Shaoxing wastewater treatment plant (SWWTP) is composed of more than 90% dyeing and printing wastewater with high pH and sulfate. Through a combination process of anaerobic acidogenic [hydraulic retention time (HRT) of 15h], aerobic (HRT of 20h) and flocculation-precipitation, the total COD removal efficiency was up to 91%. But COD removal efficiency in anaerobic acidogenic unit was only 4%. As a comparison, the COD removal efficiency was up to 35% in the pilot-scale upflow anaerobic sludge bed (UASB) reactor (HRT of 15h). GC-MS analysis showed that the response abundance of these wastewater samples decreased with their removal of COD. A main component of the raw influent was long-chain n-alkanes. The final effluent of SWWTP had only four types of alkanes. After anaerobic unit at SWWTP, the mass percentage of total alkanes to total organic compounds was slightly decreased while its categories increased. But in the UASB, alkanes categories could be removed by 75%. Caffeine as a chemical marker could be detected only in the effluent of the aerobic process. Quantitative analysis was given. These results demonstrated that GC-MS analysis could provide an insight to the measurement of organic compounds removal.

  18. Pilot scale test of a produced water-treatment system for initial removal of organic compounds

    SciTech Connect

    Sullivan, Enid J; Kwon, Soondong; Katz, Lynn; Kinney, Kerry

    2008-01-01

    A pilot-scale test to remove polar and non-polar organics from produced water was performed at a disposal facility in Farmington NM. We used surfactant-modified zeolite (SMZ) adsorbent beds and a membrane bioreactor (MBR) in combination to reduce the organic carbon content of produced water prior to reverse osmosis (RO). Reduction of total influent organic carbon (TOC) to 5 mg/L or less is desirable for efficient RO system operation. Most water disposed at the facility is from coal-bed gas production, with oil production waters intermixed. Up to 20 gal/d of produced water was cycled through two SMZ adsorbent units to remove volatile organic compounds (BTEX, acetone) and semivolatile organic compounds (e.g., napthalene). Output water from the SMZ units was sent to the MBR for removal of the organic acid component of TOC. Removal of inorganic (Mn and Fe oxide) particulates by the SMZ system was observed. The SMZ columns removed up to 40% of the influent TOC (600 mg/L). BTEX concentrations were reduced from the initial input of 70 mg/L to 5 mg/L by the SMZ and to an average of 2 mg/L after the MBR. Removal rates of acetate (input 120-170 mg/L) and TOC (input up to 45 mg/L) were up to 100% and 92%, respectively. The water pH rose from 8.5 to 8.8 following organic acid removal in the MBR; this relatively high pH was likely responsible for observed scaling of the MBR internal membrane. Additional laboratory studies showed the scaling can be reduced by metered addition of acid to reduce the pH. Significantly, organic removal in the MBR was accomplished with a very low biomass concentration of 1 g/L throughout the field trial. An earlier engineering evaluation shows produced water treatment by the SMZ/MBR/RO system would cost from $0.13 to $0.20 per bbl at up to 40 gpm. Current estimated disposal costs for produced water are $1.75 to $4.91 per bbl when transportation costs are included, with even higher rates in some regions. Our results suggest that treatment by an SMZ

  19. Review of Organic Wastewater Compound Concentrations and Removal in Onsite Wastewater Treatment Systems.

    PubMed

    Schaider, Laurel A; Rodgers, Kathryn M; Rudel, Ruthann A

    2017-07-05

    Onsite wastewater treatment systems, such as septic systems, serve 20% of U.S. households and are common in areas not served by wastewater treatment plants (WWTPs) globally. They can be sources of nutrients and pathogen pollution and have been linked to health effects in communities where they contaminate drinking water. However, few studies have evaluated their ability to remove organic wastewater compounds (OWCs) such as pharmaceuticals, hormones, and detergents. We synthesized results from 20 studies of 45 OWCs in conventional drainfield-based and alternative onsite wastewater treatment systems to characterize concentrations and removal. For comparison, we synthesized 31 studies of these same OWCs in activated sludge WWTPs. OWC concentrations and removal in drainfields varied widely and depended on wastewater sources and compound-specific removal processes, primarily sorption and biotransformation. Compared to drainfields, alternative systems had similar median and higher maximum concentrations, reflecting a wider range of system designs and redox conditions. OWC concentrations and removal in drainfields were generally similar to those in conventional WWTPs. Persistent OWCs in groundwater and surface water can indicate the overall extent of septic system impact, while the presence of well-removed OWCs, such as caffeine and acetaminophen, may indicate discharges of poorly treated wastewater from failing or outdated septic systems.

  20. Soil washing process for the removal of hydrophobic organic compounds from soils and sediments

    SciTech Connect

    Steiner, W.

    1988-01-01

    A new process concept for the removal of organic pollutants from soils and sediments is presented. The organic pollutants to be removed are primarily hydrophobic organic compounds (HOC), e.g. polychlorinated biphenyls, polychlorinated dioxins, polychlorinated dibenzofurans, penta-, tri- and monochlorophenols, polyaromatic hydrocarbons and pesticides. The main objectives of this process concept include: (1) the conversion of solid waste to a liquid waste for easier handling, (2) the achievement of a significant volume reduction of the initial waste stream and (3) the safe ultimate disposal of the reduced volume of the liquid waste containing the contaminants, with minimal energy expenditures. The four principal steps of the process are, solid-liquid separation, solvent leaching, liquid-liquid extraction and adsorption. An analytical model has been developed for the entire process, and is presented together with sample calculations for the individual steps. The model allows for the optimization of the process for any specified scenario.

  1. Removal of volatile organic compounds in the confined space using atmospheric pressure discharge plasmas

    NASA Astrophysics Data System (ADS)

    Matsuoka, Y.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.; Toyoura, T.; Matsui, M.; Kishimoto, T.

    2013-10-01

    Volatile organic compounds (VOCs) are regulated as hazardous pollutants. Thus, the control of VOCs in the atmosphere is one of the most important environmental problems. Removal of VOCs has been generally carried out by conventional methods such as absorption, adsorption and incineration. There are some researches on development of removal system using atmospheric pressure discharge plasmas. In this study, the plasma process is applied to removal of VOCs in the confined space such as an underwater vehicle because of low operating temperature and compact system. A copper wire is helically wound outside a glass tube, and a tungsten rod is inserted inside the glass tube. A dielectric barrier discharge (DBD) plasma is produced inside the glass tube by a high-voltage bipolar power supply for the removal of VOC. The DBD plasma decomposed hexane with the initial concentration of 30 ppm diluted by nitrogen, air and humid air. As the result, the removal efficiency of hexane diluted by nitrogen, air and humid air was 15%, 45% and 80%, respectively. Thus, it is considered that O and OH radicals are effective for removal of hexane. Optimization of the electrodes and the applied voltage waveforms for the enhancement of removal efficiency and the reduction of second products such as ozone will be investigated.

  2. Removal of bulk dissolved organic carbon (DOC) and trace organic compounds by bank filtration and artificial recharge.

    PubMed

    Grünheid, Steffen; Amy, Gary; Jekel, Martin

    2005-09-01

    Bank filtration and artificial recharge provide an important drinking water source to the city of Berlin. Due to the practice of water recycling through a semi-closed urban water cycle, the introduction of effluent organic matter (EfOM) and persistent trace organic pollutants in the drinking water is of potential concern. In the work reported herein, the research objectives are to study the removal of bulk and trace organics at bank filtration and artificial recharge sites and to assess important factors of influence for the Berlin area. The monthly analytical program is comprised of dissolved organic carbon (DOC), UV absorbance (UVA254), liquid chromatography with organic carbon detection (LC-OCD), differentiated adsorbable organic halogens (AOX) and single organic compound analysis of a few model compounds. More than 1 year of monitoring was conducted on observation wells located along the flowpaths of the infiltrating water at two field sites that have different characteristics regarding redox conditions, travel time, and travel distance. Two transects are highlighted: one associated with a bank filtration site dominated by anoxic/anaerobic conditions with a travel time of up to 4-5 months, and another with an artificial recharge site dominated by aerobic conditions with a travel time of up to 50 days. It was found that redox conditions and travel time significantly influence the DOC degradation kinetics and the efficiency of AOX and trace compound removal.

  3. Removal of volatile organic compounds using amphiphilic cyclodextrin-coated polypropylene

    PubMed Central

    Lumholdt, Ludmilla; Fourmentin, Sophie; Nielsen, Thorbjørn T

    2014-01-01

    Summary Polypropylene nonwovens were functionalised using a self-assembled, amphiphilic cyclodextrin coating and the potential for water purification by removal of pollutants was studied. As benzene is one of the problematic compounds in the Water Framework Directive, six volatile organic compounds (benzene and five benzene-based substances) were chosen as model compounds. The compounds were tested as a mixture in order to provide a more realistic situation since the wastewater will be a complex mixture containing multiple pollutants. The volatile organic compounds are known to form stable inclusion complexes with cyclodextrins. Six different amphiphilic cyclodextrin derivatives were synthesised in order to elucidate whether or not the uptake abilities of the coating depend on the structure of the derivative. Headspace gas chromatography was used for quantification of the uptake exploiting the volatile nature of benzene and its derivatives. The capacity was shown to increase beyond the expected stoichiometries of guest–host complexes with ratios of up to 16:1. PMID:25550739

  4. Can ornamental potted plants remove volatile organic compounds from indoor air? A review.

    PubMed

    Dela Cruz, Majbrit; Christensen, Jan H; Thomsen, Jane Dyrhauge; Müller, Renate

    2014-12-01

    Volatile organic compounds (VOCs) are found in indoor air, and many of these can affect human health (e.g. formaldehyde and benzene are carcinogenic). Plants affect the levels of VOCs in indoor environments, thus they represent a potential green solution for improving indoor air quality that at the same time can improve human health. This article reviews scientific studies of plants' ability to remove VOCs from indoor air. The focus of the review is on pathways of VOC removal by the plants and factors affecting the efficiency and rate of VOC removal by plants. Laboratory based studies indicate that plant induced removal of VOCs is a combination of direct (e.g. absorption) and indirect (e.g. biotransformation by microorganisms) mechanisms. They also demonstrate that plants' rate of reducing the level of VOCs is influenced by a number of factors such as plant species, light intensity and VOC concentration. For instance, an increase in light intensity has in some studies been shown to lead to an increase in removal of a pollutant. Studies conducted in real-life settings such as offices and homes are few and show mixed results.

  5. Comparing removal of trace organic compounds and assimilable organic carbon (AOC) at advanced and traditional water treatment plants.

    PubMed

    Lou, Jie-Chung; Lin, Chung-Yi; Han, Jia-Yun; Tseng, Wei-Biu; Hsu, Kai-Lin; Chang, Ting-Wei

    2012-06-01

    Stability of drinking water can be indicated by the assimilable organic carbon (AOC). This AOC value represents the regrowth capacity of microorganisms and has large impacts on the quality of drinking water in a distribution system. With respect to the effectiveness of traditional and advanced processing methods in removing trace organic compounds (including TOC, DOC, UV(254), and AOC) from water, experimental results indicate that the removal rate of AOC at the Cheng Ching Lake water treatment plant (which utilizes advanced water treatment processes, and is hereinafter referred to as CCLWTP) is 54%, while the removal rate of AOC at the Gong Yuan water treatment plant (which uses traditional water treatment processes, and is hereinafter referred to as GYWTP) is 36%. In advanced water treatment units, new coagulation-sedimentation processes, rapid filters, and biological activated carbon filters can effectively remove AOC, total organic carbon (TOC), and dissolved organic carbon (DOC). In traditional water treatment units, coagulation-sedimentation processes are most effective in removing AOC. Simulation results and calculations made using the AutoNet method indicate that TOC, TDS, NH(3)-N, and NO(3)-N should be regularly monitored in the CCLWTP, and that TOC, temperature, and NH(3)-N should be regularly monitored in the GYWTP.

  6. Removal of volatile organic compounds by natural materials during composting of poultry litter.

    PubMed

    Turan, N G; Akdemir, A; Ergun, O N

    2009-01-01

    The objective of this study was to reduce volatile organic compounds (VOCs) produced during composting of poultry litter. The natural zeolite, expanded perlite, pumice and expanded vermiculite as the natural materials were used for the reducing of VOCs. Composting was performed in a laboratory scale in-vessel composting plant. Poultry litter was composted for 100 d with volumetric ratio of natural materials:poultry litter of 1:10. The VOCs were tested using the FT-IR method by VOCs analyzer. Studies showed that VOCs generation was the greatest in the control treatment without any natural materials. The natural materials significantly reduced VOCs. At the end of the processes, removal efficiency was 79.73% for NZ treatment, 54.59% for EP treatment, 88.22% for P treatment and 61.53% for EV treatment. Potential of removal for VOCs on poultry litter matrix using natural materials was in order of: P>NZ>EV>EP.

  7. Wet scrubber analysis of volatile organic compound removal in the rendering industry.

    PubMed

    Kastner, James R; Das, K C

    2002-04-01

    The promulgation of odor control rules, increasing public concerns, and U.S. Environmental Protection Agency (EPA) air regulations in nonattainment zones necessitates the remediation of a wide range of volatile organic compounds (VOCs) generated by the rendering industry. Currently, wet scrubbers with oxidizing chemicals are used to treat VOCs; however, little information is available on scrubber efficiency for many of the VOCs generated within the rendering process. Portable gas chromatography/mass spectrometry (GC/MS) units were used to rapidly identify key VOCs on-site in process streams at two poultry byproduct rendering plants. On-site analysis was found to be important, given the significant reduction in peak areas if samples were held for 24 hr before analysis. Major compounds consistently identified in the emissions from the plant included dimethyl disulfide, methanethiol, octane, hexanal, 2-methylbutanal, and 3-methylbutanal. The two branched aldehydes, 2-methylbutanal and 3-methylbutanal, were by far the most consistent, appearing in every sample and typically the largest fraction of the VOC mixture. A chlorinated hydrocarbon, methanesulfonyl chloride, was identified in the outlet of a high-intensity wet scrubber, and several VOCs and chlorinated compounds were identified in the scrubbing solution, but not on a consistent basis. Total VOC concentrations in noncondensable gas streams ranged from 4 to 91 ppmv. At the two plants, the odor-causing compound methanethiol ranged from 25 to 33% and 9.6% of the total VOCs (v/v). In one plant, wet scrubber analysis using chlorine dioxide (ClO2) as the oxidizing agent indicated that close to 100% of the methanethiol was removed from the gas phase, but removal efficiencies ranged from 20 to 80% for the aldehydes and hydrocarbons and from 23 to 64% for total VOCs. In the second plant, conversion efficiencies were much lower in a packed-bed wet scrubber, with a measurable removal of only dimethyl sulfide (20-100%).

  8. Simultaneous removal of organic matter and nitrogen compounds by an aerobic/anoxic membrane biofilm reactor.

    PubMed

    Hasar, Halil; Xia, Siqing; Ahn, Chang Hoon; Rittmann, Bruce E

    2008-09-01

    The hydrogen-based membrane biofilm reactor (MBfR) has been well studied and applied for denitrification of nitrate-containing water and wastewater. Adding an oxygen-based MBfR allows total-nitrogen removal when the input nitrogen is ammonium. However, most wastewaters also contain a significant concentration or organic material, measured as chemical oxygen demand (COD). This study describes experiments to investigate the removal of organic and nitrogenous compounds in the combined Aerobic/Anoxic MBfR, in which an Aerobic MBfR (Aer MBfR) precedes an Anoxic MBfR (An MBfR). The experiments demonstrate that the Aer/An MBfR combination accomplished COD oxidation and nitrogen removal for a total oxygen demand flux (i.e., from COD and NH(4) oxidations) in the range of 1.2-7.2 g O(2)/m(2)-d for 4.5 psi (0.3 atm) oxygen pressure to the Aer MBfR, but was overloaded and did not accomplish nitrification for the total oxygen demand load higher than 14 g O(2)/m(2)-d. Total-nitrogen removal was controlled by nitrification in the Aer MBfR, because the An MBfR denitrified all NO(3)(-) provided to it by the Aer MBfR. The overload of total oxygen demand did not affect COD oxidation in the Aer MBfR, but caused a small increase of COD in the An MBfR due to net release of soluble microbial products (SMP).

  9. Removal of easily biodegradable organic compounds by drinking water biofilms: analysis of kinetics and mass transfer.

    PubMed

    Gagnon, G A; Huck, P M

    2001-07-01

    This paper evaluates the rate of utilization of easily biodegradable organic compounds by drinking water biofilms. Tap water, which had been filtered through biologically active granular activated carbon, was used as an innoculum for biofilm growth in annular reactors (ARs). Synthetic cocktails of easily biodegradable material in the concentration range of 50-2,000 mgC/m3 were used as substrate for biofilm growth. Influent and effluent aggregate concentrations of biodegradable organic matter (BOM) were calculated by adding the measurable BOM components on a mass carbon basis. The aggregate BOM values were used for calculating the observed Damköhler number and Theile modulus (based on a reaction rate per unit surface area), which were used to determine whether external or internal mass transfer limited BOM removal. For all of the experimental trials, it was shown that neither external nor internal mass transfer limited BOM removal. Because the biofilms in this research are thin and the fact that mass transfer is not limiting, it was assumed that the bulk BOM concentration was approximately equal to the average BOM concentration in the biofilm. A linear model was obtained for the aggregate BOM flux and the product of the effluent BOM concentration and the biofilm density. The slope or the areal biodegradation rate (ka) for the aggregate BOM was 0.033 m/h, as determined through a linear regression.

  10. EMERGING TECHNOLOGY BULLETIN: VOLATILE ORGANIC COMPOUND REMOVAL FROM AIR STREAMS BY MEMBRANES SEPARATION MEMBRANE TECHNOLOGY AND RESEARCH, INC.

    EPA Science Inventory

    This membrane separation technology developed by Membrane Technology and Research (MTR), Incorporated, is designed to remove volatile organic compounds (VOCs) from contaminated air streams. In the process, organic vapor-laden air contacts one side of a membrane that is permeable ...

  11. EMERGING TECHNOLOGY BULLETIN: VOLATILE ORGANIC COMPOUND REMOVAL FROM AIR STREAMS BY MEMBRANES SEPARATION MEMBRANE TECHNOLOGY AND RESEARCH, INC.

    EPA Science Inventory

    This membrane separation technology developed by Membrane Technology and Research (MTR), Incorporated, is designed to remove volatile organic compounds (VOCs) from contaminated air streams. In the process, organic vapor-laden air contacts one side of a membrane that is permeable ...

  12. Organic silicon compounds anf hydrogen sulfide removal from biogas by mineral and adsorbent

    NASA Astrophysics Data System (ADS)

    Choi, J.

    2015-12-01

    Biogas utilized for energy production needs to be free from organic silicon compounds and hydrogen sulfide , as their burning has damaging effects on utilities and humans; organic silicon compounds and hydrogen sulfide can be found in biogas produced from biomass wastes, due to their massive industrial use in synthetic product,such as cosmetics, detergents and paints.Siloxanes and hydrogen sulfide removal from biogas can be carried out by various methods (Ajhar et al., 2010); aim of the present work is to find a single practical andeconomic way to drastically and simultaneously reduce both hydrogen sulfide and the siloxanes concentration to less than 1 ppm. Some commercial activated carbons previously selected (Monteleoneet al., 2011) as being effective in hydrogen sulfide up taking have been tested in an adsorption measurement apparatus, by flowing both hydrogen sulphide and volatile siloxane (Decamethycyclopentasiloxane or D5) in a nitrogen stream,typically 25-300 ppm D5 over N2, through an clay minerals, Fe oxides and Silica; the adsorption process was analyzed by varying some experimental parameters (concentration, grain size, bed height). The best silica shows an adsorption capacity of 0.2 g D5 per gram of silica. The next thermo gravimetric analysis (TGA) confirms the capacity data obtained experimentally by the breakthrough curve tests.The capacity results depend on D5 and hydrogen sulphide concentrations. A regenerative silica process is then carried out byheating the silica bed up to 200 ° C and flushing out the adsorbed D5 and hydrogen sulphide samples in a nitrogen stream in athree step heating procedure up to 200 ° C. The adsorption capacity is observed to degrade after cyclingthe samples through several adsorption-desorption cycles.

  13. Removal of volatile organic compounds by heterogeneous ozonation on microporous synthetic alumina silicate.

    PubMed

    Brodu, Nicolas; Zaitan, Hicham; Manero, Marie-Hélène; Pic, Jean-Stéphane

    2012-01-01

    A hybrid process combining adsorption and ozonation was examined as an alternative treatment for odorous volatile organic compounds (VOCs). Methyl ethyl ketone (MEK) was chosen to study the influence of operating parameters. Two synthetic aluminosilicates (faujasite-Y and ZSM-5) were tested for adsorption and reactivity with ozone. The adsorption equilibrium measurement on both adsorbents showed that adsorption performance depends on temperature but is not sensitive to relative humidity, due to the hydrophobic properties of the materials. Adsorbed VOCs were oxidized at low temperature when ozonated flow was sent to the reactor. Regeneration of the fixed bed was achieved at the same time, releasing mainly CO(2) and H(2)O. Intermediates of oxidation, such as 2,3-butanedione and acetic acid, were identified, leading to incomplete mineralization. The influence of concentration and humidity are discussed. Four successive cycles were tested: after the first adsorption/ozonation cycle, the adsorption efficiency was not affected during subsequent cycles. These results show that the same sample of adsorbent can be used in the treatment process for a long time. Ozonation regeneration is a promising process for VOC removal.

  14. Characteristics of volatile compounds removal in biogas slurry of pig manure by ozone oxidation and organic solvents extraction.

    PubMed

    Wang, Yujun; Feng, Lianshuang; Zhao, Xiaosong; Ma, Xiulan; Yang, Jingmin; Liu, Huiqing; Dou, Sen; Zhou, Miping; Xie, Zhonglei

    2013-09-01

    Biogas slurry is not suitable for liquid fertilizer due to its high amounts of volatile materials being of complicated composition and peculiar smell. In order to remove volatiles from biogas slurry efficiently, the dynamic headspace and gas chromatography-mass spectrometry were used to clear the composition of volatiles. Nitrogen stripping and superfluous ozone were also used to remove volatiles from biogas slurry. The results showed that there were 21 kinds of volatile compounds in the biogas slurry, including sulfur compounds, organic amines, benzene, halogen generation of hydrocarbons and alkanes, some of which had strong peculiar smell. The volatile compounds in biogas slurry can be removed with the rate of 53.0% by nitrogen stripping and with rate of 81.7% by the oxidization and stripping of the superfluous ozone. On this basis, the removal rate of the volatile compounds reached 99.2% by chloroform and n-hexane extraction, and almost all of odor was eliminated. The contents of some dissolved organic compounds decreased obviously and however main plant nutrients had no significant change in the biogas slurry after being treated.

  15. Evaluation of o-xylene and other volatile organic compounds removal using a xylene-acclimated biotrickling filter.

    PubMed

    Wang, Xiang-Qian; Lu, Bi-Hong; Zhou, Xue-Xia; Li, Wei

    2013-01-01

    In this study, performance evaluation for the gas-phase o-xylene removal using a xylene-acclimated biotrickling filter (BTF) was conducted. Substrate interactions during aerobic biodegradation of three poorly soluble compounds, both individually and in paired mixtures (namely, o-xylene and ethyl acetate, o-xylene and dichloromethane, which are common solvents used by pharmaceutical industry), were also investigated. Experimental results indicate that a maximum elimination capacity of 99.3 g x m(-3) x h(-1) (70% removal) was obtained at an o-xylene loading rate of 143.0 g x m(-3) x h(-1), while the top packing layer (one-third height of the three packing layers) only contributed about 13% to the total elimination capacity. Kinetic constants for o-xylene biodegradation and the pattern of o-xylene removal performance along the height of the BTF were obtained through the modified Michaelis-Menten kinetics and convection-diffusion reaction model, respectively. A reduction of removal efficiency in o-xylene (83.2-74.5% removal at a loading rate of 40.3 g x m(-3) x h(-1) for the total volatile organic compound (VOC) loading rate of 79 g x m(-3) x h(-1)) in the presence of ethyl acetate (100% removal) was observed, while enhanced o-xylene removal efficiency (71.6-78.6% removal at a loading rate of 45.1 g x m(-3) x h(-1) for the total VOC loading rate of 90 g x m(-3) x h(-1)) was achieved in the presence of dichloromethane (35.6% removal). This work shows that a BTF with xylene-acclimated microbial consortia has the ability to remove several poorly soluble compounds, which would advance the knowledge on the treatment of pharmaceutical VOC emissions.

  16. COST ANALYSIS OF ACTIVATED CARBON VERSUS PHOTOCATALYTIC OXIDATION FOR REMOVING ORGANIC COMPOUNDS FROM INDOOR AIR

    EPA Science Inventory

    A cost comparison has been conducted of 1 m3/s indoor air cleaners using granular activated carbon (GAC) vs. photocatalytic oxidation (PCO) for treating a steady-state inlet volatile organic compound (VOC) concentration of 0.3 mg/m3. The commercial GAC unit was costed assuming t...

  17. COST ANALYSIS OF ACTIVATED CARBON VERSUS PHOTOCATALYTIC OXIDATION FOR REMOVING ORGANIC COMPOUNDS FROM INDOOR AIR

    EPA Science Inventory

    A cost comparison has been conducted of 1 m3/s indoor air cleaners using granular activated carbon (GAC) vs. photocatalytic oxidation (PCO) for treating a steady-state inlet volatile organic compound (VOC) concentration of 0.3 mg/m3. The commercial GAC unit was costed assuming t...

  18. MODELING OF MULTICOMPONENT PERVAPORATION FOR REMOVAL OF VOLATILE ORGANIC COMPOUNDS FROM WATER

    EPA Science Inventory

    A resistance-in-series model was used to study the pervaporation of multiple volatile organic compounds (VOCs)-water mixtures. Permeation experiments were carried out for four membranes: poly(dimethylsiloxane) (PDMS), polyether-block-polyamides (PEBA), polyurethane (PUR) and sil...

  19. MODELING OF MULTICOMPONENT PERVAPORATION FOR REMOVAL OF VOLATILE ORGANIC COMPOUNDS FROM WATER

    EPA Science Inventory

    A resistance-in-series model was used to study the pervaporation of multiple volatile organic compounds (VOCs)-water mixtures. Permeation experiments were carried out for four membranes: poly(dimethylsiloxane) (PDMS), polyether-block-polyamides (PEBA), polyurethane (PUR) and sil...

  20. Emission of odorous volatile organic compounds from a municipal manure treatment plant and their removal using a biotrickling filter.

    PubMed

    Li, Jian-Jun; Wu, Yan-Di; Zhang, Yan-Li; Zeng, Pei-Yuan; Tu, Xiang; Xu, Mei-Ying; Sun, Guo-Ping

    2015-01-01

    Odorous volatile organic compounds (VOCs) from municipal manure treatment facilities are considered as a major nuisance issue for operators and nearby residents. In this study, up to 71 odorous VOCs were detected by gas chromatography-mass spectrometry at the manure treatment plant. These compounds can be classified into five different categories, including alkanes, olefins, aromatics, volatile organosulphur compounds and terpenes. Toluene, dimethyl disulphide, dimethyl sulphide, xylene and ethylbenzene were the five most abundant pollutants. A pilot-scale biotrickling filter (BTF) was employed to treat the complex odorous gases. Correlation analysis showed that the removal efficiency (RE) of the BTF was related with the molecular weight and chemical structure of contaminants. Higher than 85% of REs could be reached for aromatic, terpenes and most alkanes compounds after 180 days of operation. Comparatively, most olefins and partial alkanes compounds with a molecular weight lower than 70 were not removed easily. The REs of these compounds ranged from 0% to 94%, and the average removal efficiency (RE) was only about 33.3%.

  1. The effect of microwave electromagnetic radiation on organic compounds removal efficiency in a reactor with a biofilm.

    PubMed

    Zielinski, M; Krzemieniewski, M

    2007-01-01

    This article shows the results of research on microwave radiation as a factor affecting organic compounds removal in a reactor with a biofilm. In the experiment a bioreactor was situated inside a microwave tube and there exposed to radiation. Municipal wastes were supplied to the bioreactor from a retention tank, to which they returned having passed through the reactor's packing. The whole system operated in a time cycle comprising a 24-hour detention of the wastewaters supply. The research was based on the specific properties of microwave heating, i.e. their ability to heat only the substances of appropriate dielectric properties. As the reactor was properly constructed and the microwave generator work was synchronised with that of the volumetric pump, microwave energy was directed mostly to the biofilm. It was observed that as a result of microwave radiation the process of organic compounds removal, defined as Chemical Oxygen Demand COD, increased its rate nearly by half. Simultaneously the process efficiency increased by 7.7% at the maximum. While analysing the changes the organic compounds underwent it was revealed that the load in-built in the biomass decreased by over half as a result of microwave radiation input at 2.5 W s(-1), which was optimal under the experimental conditions. Similarly the amount of pollutant remaining in the treated effluent decreased nearly by half, whereas the role of oxidation in removing organic pollutant increased in excess of 25% when compared to the control system.

  2. Modeling of multicomponent pervaporation for removal of volatile organic compounds from water

    SciTech Connect

    Ji, W.; Sikdar, S.K.; Hwang, S.T.

    1994-01-01

    A resistance-in-series model was used to study the pervaporation of multiple volatile organic compounds (VOCs)-water mixtures. Permeation experiments were carried out for four membranes and three VOCs. The membrane permeability were calculated in terms of the resistance-in-series model. The membrane performances were then compared with each other based on the permeabilities. Both organic and water permeabilities of polyether-block-polyamides (PEBA) membrane for one VOC-water, two VOC-water, and three VOC-water mixtures were found to be comparable with each other.

  3. An Evaluation of Technology to Remove Problematic Organic Compounds from the International Space Station Potable Water

    NASA Technical Reports Server (NTRS)

    Rector, Tony; Metselaar, Carol; Peyton, Barbara; Steele, John; Michalek, William; Bowman, Elizabeth; Wilson, Mark; Gazda, Daniel; Carter, Layne

    2014-01-01

    Since activation of the Water Processor Assembly (WPA) on the International Space Station (ISS) in November of 2008, there have been three events in which the TOC (Total Organic Carbon) in the product water has increased to approximately 3 mg/L and has subsequently recovered. Analysis of the product water in 2010 identified the primary component of the TOC as dimethylsilanediol (DMSD). An investigation into the fate of DMSD in the WPA ultimately determined that replacement of both Multifiltration (MF) Beds is the solution to recovering product water quality. The MF Beds were designed to ensure that ionic breakthrough occurs before organic breakthrough. However, DMSD saturated both MF Beds in the series, requiring removal and replacement of both MF Beds with significant life remaining. Analysis of the MF Beds determined that the adsorbent was not effectively removing DMSD, trimethylsilanol, various polydimethylsiloxanes, or dimethylsulfone. Coupled with the fact that the current adsorbent is now obsolete, the authors evaluated various media to identify a replacement adsorbent as well as media with greater capacity for these problematic organic contaminants. This paper provides the results and recommendations of this collaborative study.

  4. NEG (non evaporable getter) pumps for organic compounds and water removal in EUVL tools

    NASA Astrophysics Data System (ADS)

    Conte, A.; Manini, P.; Raimondi, S.

    2008-03-01

    One of present EUVL challenges is to reduce as much as possible the organic compounds and water partial pressures during the lithographic process. These gases can in fact interact with sensitive surfaces and, in the presence of EUV radiation, decompose to generate carbon-based films and oxides, which are detrimental to the optics, reducing its performance, lifetime and significantly increasing the equipment total cost of ownership. With this respect, use of Non Evaporable Getter (NEG) pumps seems particularly attractive. Getter pumps are very clean, vibration-free, compact, able to deliver large pumping speed for all active gases, including water and hydrogen. In the present paper, we report for the first time the results of specific tests aimed at measuring the pumping speed for some selected organic compounds, namely toluene and decane (n-decane). The study shows that getter pumps can effectively sorb these large organic molecules with high speed and capacity. Speed and capacity increases when operating the getter cartridge at moderate temperature (e.g. 150-200°C), however remarkable sorption is achieved, even at room temperature, without any power applied. When coupled with turbo-molecular pumps NEG pumps have therefore the potential to improve the ultimate vacuum and mitigate the carbon/oxygen contamination in a UHV lithographic system.

  5. Adsorption of phenolic compounds by organoclays: implications for the removal of organic pollutants from aqueous media.

    PubMed

    Park, Yuri; Ayoko, Godwin A; Kurdi, Róbert; Horváth, Erzsébet; Kristóf, Janos; Frost, Ray L

    2013-09-15

    Montmorillonite (MMT) was converted to organoclays by intercalation of cationic surfactants into its interlayer space. Two types of organoclays were prepared from different surfactants (DDTMA and DDDMA) at different surfactant loadings, and the structural changes in the clays investigated using various techniques. The arrangements of surfactant molecules in the interlayer space was visually aided by molecular mechanical calculation (MM calculation), and the adsorption capacities of MMT and the organoclays for the removal of p-chlorophenol (PCP) and p-nitrophenol (PNP) from aqueous solutions were tested under different conditions. Two adsorption isotherm models (Langmuir and Freundlich isotherms) were used to determine the best fit model and the Freundlich isotherm was found to provide better fit for both PCP and PNP. Due to its hydrophobic properties, the adsorption is more favourable for PNP than PCP. Overall, the adsorption capacity of the organoclays was significantly improved by intercalation with large surfactant molecules as well as highly loaded surfactants as the intercalation with large surfactant molecules created the partitioning phase, which strongly attracted large amounts of organic pollutants. Possible mechanisms and the implications of the results for the use of these organoclays as adsorbents for the removal of phenols from the environment are discussed.

  6. Selective oxidations of organosulfur model compounds and coal for the removal of organic sulfur

    SciTech Connect

    Fauth, D.J.; Baltrus, J.P.; Nowak, M.A.; Olson, G.J.

    1991-01-01

    Investigations with organosulfur compounds have established that potassium monopersulfate (Oxone) in aqueous ethanol and sodium perborate in glacial acetic acid are highly selective oxidants for the oxidation of organic sum ides and aromatic sulfur heterocycles to their corresponding sulfoxides and sulfones. In a series of selective oxidations, dibenzothiophene in ethanol, fluorene in ethanol, and a 50:50 mol mixture of dibenzothiophene (DBT) and fluoresce in ethanol were reacted with aqueous Oxone under mild conditions. Capillary gas chromatographic analyses showed conversions of DBT to DBT-5,5-dioxide, while its carbon analog, fluorene was recovered quantitatively in every case. Furthermore, selective oxidations with Oxone of a triboelectrostatically cleaned Illinois {number sign}6 ultrafine coal (400 mesh {times} 0) and an Illinois {number sign}6 coal (IBC-101) (200 mesh {times} 0) depyritized via microorganisms were investigated. X-ray photoelectron spectroscopic (XPS) data indicated oxidation of a large fraction of the organic sulfur on the coal surface. Approximately 55--85% of the total S 2p area could be attributed to oxidized organic sulfur in the form of sulfones.

  7. Cross-linked smart poly(dimethylsiloxane) membranes for removal of volatile organic compounds in water

    NASA Astrophysics Data System (ADS)

    Ohshima, Tadahiro; Miyata, Takashi; Uragami, Tadashi; Berghmens, Hugo

    2005-04-01

    This paper focuses on the effects of fluorine cross-linker of the cross-linked poly(dimethylsiloxane) membranes from polydimethylsiloxane dimethylmethacrylate macromonomer (PDMSDMMA) and divinyl perfluoro- n-hexane (DVF) on the pervaporation characteristics of the removal of benzene from an aqueous solution of dilute benzene. When an aqueous solution of 0.05 wt% benzene was permeated through the cross-linked PDMSDMMA (PDMSDMMA-DVF) membranes, they showed a high benzene permselectivity and permeability of these membranes was enhanced with increasing DVF content significantly. The best normalized permeation rate, separation factor for benzene permselectivity, and pervaporation separation index (PSI) of a PDMSDMMA-DVF membrane were 1.72×10 -5 kg m/m 2 h, 4316, and 7423, respectively. The best normalized permeation rate of a PDMSDMMA-DVF membrane was approximately same as the PDMSDMMA membranes cross-linked with other divinyl compounds, but the separation factor and PSI of the former membrane were greater than those of the latter ones. These pervaporation characteristics are discussed from the viewpoint of chemical and physical structure of the cross-linked PDMSDMMA-DVF membranes in detail.

  8. Removal of organic and inorganic sulfur compounds by ozone and granular activated carbon

    SciTech Connect

    Shepherd, B.; Ball, G.W.

    1996-11-01

    Most groundwater supplies in the western U.S. are relatively low in dissolved organic matter, are generally free of bacteria, and are platable to their consumers. In areas of western Nevada, certain groundwaters are near active geothermal areas, which can produce sulfurous types of tastes and odors (T&Os) in the water. Other water quality characteristics can consist of either relatively low or highly mineralized waters, variations in pH, and temperatures ranging from those slightly above normal groundwaters to pressurized steam. Watersource Consulting Engineers (WCE) and Shepherd Laboratories (SL) conducted an engineering study of a high-capacity well for a local northwestern Nevada utility. WCE`s original task had been to design pumping and storage facilities for the well, in addition to evaluating basic treatment. Originally, WCE anticipated designing facilities to remove hydrogen sulfide (H{sub 2}S) and reduce color, primarily with chlorination and aeration. SL was requested to evaluate existing water quality and eventually conduct bench-scale testing of several treatment processes. As the study proceeded, the original goals were modified when it became evident that water quality conditions required more extensive evaluation. The study was done in several stages, reflecting the information gained during each stage. The final recommended design criteria included treatment for improving water quality relative to T&O, color, total organic carbon (TOC), and, to a limited extent, fluoride. The water quality goals adopted by the utility encompassed primary maximum contaminant levels (MCLs) for regulatory compliance and secondary MCLs for aesthetically pleasing water. The treatment processes evaluated and recommended in this study were designed primarily to improve the aesthetic qualities of color, taste, and odor. Fluoride reduction was evaluated but was not included in the final design requirements, except for the overall reduction provided by the recommended process.

  9. DEMONSTRATION OF PILOT-SCALE PERVAPORATION SYSTEMS FOR VOLATILE ORGANIC COMPOUND REMOVAL FROM A SURFACTANT ENHANCED AQUIFER REMEDIATION FLUID. II. HOLLOW FIBER MEMBRANE MODULES

    EPA Science Inventory

    Pilot-scale demonstration of pervaporation-based removal of volatile organic compounds from a surfactant enhanced aquifer remediation (SEAR) fluid has been conducted at USEPA's Test & Evaluation Facility using hollow fiber membrane modules. The membranes consisted of microporous...

  10. DEMONSTRATION OF PILOT-SCALE PERVAPORATION SYSTEMS FOR VOLATILE ORGANIC COMPOUND REMOVAL FROM A SURFACTANT ENHANCED AQUIFER REMEDIATION FLUID. II. HOLLOW FIBER MEMBRANE MODULES

    EPA Science Inventory

    Pilot-scale demonstration of pervaporation-based removal of volatile organic compounds from a surfactant enhanced aquifer remediation (SEAR) fluid has been conducted at USEPA's Test & Evaluation Facility using hollow fiber membrane modules. The membranes consisted of microporous...

  11. Organic compound destruction and removal efficiency (DRE) for plasma incinerator off-gases using an electrically heated secondary combustion chamber

    SciTech Connect

    Whitworth, C.G.; Babko-Malyi, S.; Battleson, D.M.; Olstad, S.J.

    1998-12-31

    The US Department of Energy (DOE) sponsored a series pilot-scale plasma incineration tests of simulated mixed wastes at the MSE Technology Applications, Inc. technology development test facility in Butte, MT. One of the objectives of the test series was to assess the ability of an electrically heated afterburner to destroy organic compounds that may be present in the off-gases resulting from plasma incineration of mixed wastes. The anticipated benefit of an electrically heated afterburner was to decrease total off-gas volume by 50% or more, relative to fossil fuel-fired afterburners. For the present test series, feeds of interest to the DOE Mixed Waste Focus Area (MWFA) were processed in a plasma centrifugal furnace while metering selected organic compounds upstream of the electrically heated afterburner. The plasma furnace was equipped with a transferred-mode torch and was operated under oxidizing conditions. Feeds consisted of various mixtures of soil, plastics, portland cement, silicate fines, diesel fuel, and scrap metals. Benzene, chloroform, and 1,1,1-trichloroethane were selected for injection as simulates of organics likely to be present in DOE mixed wastes, and because of their relative rankings on the US Environmental Protection Agency (EPA) thermal stability index. The organic compounds were injected into the off-gas system at a nominal concentration of 2,000 ppmv. The afterburner outlet gas stream was periodically sampled, and analyzed by gas chromatography/mass spectrometry. For the electrically heated afterburner, at operating temperatures of 1,800--1,980 F (982--1,082 C), organic compound destruction and removal efficiencies (DREs) for benzene, chloroform, and 1,1,1-trichloroethane were found to be > 99.99%.

  12. Preparation of activated carbons from raw and biotreated agricultural residues for removal of volatile organic compounds.

    PubMed

    Hsi, Hsing-Cheng; Horng, Richard S; Pan, Tai-An; Lee, Shin-Ku

    2011-05-01

    Activated carbons with diverse physical and chemical properties were produced from four agriculture residues, including raw barley husk, biotreated barley husk, rice husk, and pistachio shell. Results showed that with adequate steam activation (30-90 min, 50% H2O(g),/50% N2), activated carbons with surface areas between 360 and 950 m2 g(-1) were developed. Further increases in the activation time destroyed the pore structure of activated carbons, which resulted in a decrease in the surface area and pore volume. Biotreated agricultural residues were found to be suitable precursors for producing mesoporous activated carbons. The oxygen content of activated carbons increased with increasing activation time. Results from X-ray photoelectron spectroscopy examination further suggested that H2O molecules react with the carbon surface, enhancing the deconvoluted peak area of carbonyl and carboxyl groups. Equilibrium adsorption of toluene indicated that the adsorption capacities increased with an increase in the inlet toluene concentration and a decrease in temperature. The adsorption isotherms were successfully fitted with Freundlich, Langmuir, and Dubinin-Radushkevich equations. Activated carbons derived from agricultural residues appear to be more applicable to adsorb volatile organic compounds at a low concentration and high-temperature environment.

  13. Effects of effluent organic matter characteristics on the removal of bulk organic matter and selected pharmaceutically active compounds during managed aquifer recharge: Column study.

    PubMed

    Maeng, Sung Kyu; Sharma, Saroj K; Abel, Chol D T; Magic-Knezev, Aleksandra; Song, Kyung-Guen; Amy, Gary L

    2012-10-01

    Soil column experiments were conducted to investigate the effects of effluent organic matter (EfOM) characteristics on the removal of bulk organic matter (OM) and pharmaceutically active compounds (PhACs) during managed aquifer recharge (MAR) treatment processes. The fate of bulk OM and PhACs during an MAR is important to assess post-treatment requirements. Biodegradable OM from EfOM, originating from biological wastewater treatment, was effectively removed during soil passage. Based on a fluorescence excitation-emission matrix (F-EEM) analysis of wastewater effluent-dominated (WWE-dom) surface water (SW), protein-like substances, i.e., biopolymers, were removed more favorably than fluorescent humic-like substances under oxic compared to anoxic conditions. However, there was no preferential removal of biopolymers or humic substances, determined as dissolved organic carbon (DOC) observed via liquid chromatography with online organic carbon detection (LC-OCD) analysis. Most of the selected PhACs exhibited removal efficiencies of greater than 90% in both SW and WWE-dom SW. However, the removal efficiencies of bezafibrate, diclofenac and gemfibrozil were relatively low in WWE-dom SW, which contained more biodegradable OM than did SW (copiotrophic metabolism). Based on this study, low biodegradable fractions such as humic substances in MR may have enhanced the degradation of diclofenac, gemfibrozil and bezafibrate by inducing an oligotrophic microbial community via long term starvation. Both carbamazepine and clofibric acid showed persistent behaviors and were not influenced by EfOM.

  14. Effects of effluent organic matter characteristics on the removal of bulk organic matter and selected pharmaceutically active compounds during managed aquifer recharge: Column study

    NASA Astrophysics Data System (ADS)

    Maeng, Sung Kyu; Sharma, Saroj K.; Abel, Chol D. T.; Magic-Knezev, Aleksandra; Song, Kyung-Guen; Amy, Gary L.

    2012-10-01

    Soil column experiments were conducted to investigate the effects of effluent organic matter (EfOM) characteristics on the removal of bulk organic matter (OM) and pharmaceutically active compounds (PhACs) during managed aquifer recharge (MAR) treatment processes. The fate of bulk OM and PhACs during an MAR is important to assess post-treatment requirements. Biodegradable OM from EfOM, originating from biological wastewater treatment, was effectively removed during soil passage. Based on a fluorescence excitation-emission matrix (F-EEM) analysis of wastewater effluent-dominated (WWE-dom) surface water (SW), protein-like substances, i.e., biopolymers, were removed more favorably than fluorescent humic-like substances under oxic compared to anoxic conditions. However, there was no preferential removal of biopolymers or humic substances, determined as dissolved organic carbon (DOC) observed via liquid chromatography with online organic carbon detection (LC-OCD) analysis. Most of the selected PhACs exhibited removal efficiencies of greater than 90% in both SW and WWE-dom SW. However, the removal efficiencies of bezafibrate, diclofenac and gemfibrozil were relatively low in WWE-dom SW, which contained more biodegradable OM than did SW (copiotrophic metabolism). Based on this study, low biodegradable fractions such as humic substances in MR may have enhanced the degradation of diclofenac, gemfibrozil and bezafibrate by inducing an oligotrophic microbial community via long term starvation. Both carbamazepine and clofibric acid showed persistent behaviors and were not influenced by EfOM.

  15. Use of manganese oxide and activated carbon fibers for removing a particle, volatile organic compound or ozone from a gas

    DOEpatents

    Sidheswaran, Meera A.; Destaillats, Hugo; Fisk, William J.

    2016-08-30

    The present invention provides for a device for reducing a volatile organic compound (VOC) content of a gas comprising a manganese oxide (MnO.sub.x) catalyst. The manganese oxide (MnO.sub.x) catalyst is capable of catalyzing formaldehyde at room temperature, with complete conversion, to CO.sub.2 and water vapor. The manganese oxide (MnO.sub.x) catalyst itself is not consumed by the reaction of formaldehyde into CO.sub.2 and water vapor. The present invention also provides for a device for reducing or removing a particle, a VOC and/or ozone from a gas comprising an activated carbon filter (ACF) on a media that is capable of being periodically regenerated.

  16. Particulate Matter Sampling and Volatile Organic Compound Removal for Characterization of Spark Ignited Direct Injection Engine Emissions

    SciTech Connect

    Matthias, Nick; Farron, Carrie; Foster, David E.; Andrie, Mike; Krieger, Roger; Najt, Paul; Narayanaswamy, Kushal; Solomon, Arun; Zelenyuk, Alla

    2012-01-01

    More stringent emissions regulations are continually being proposed to mitigate adverse human health and environmental impacts of internal combustion. With that in mind, it has been proposed that vehicular particulate matter (PM) emissions should be regulated based on particle number in addition to particle mass. One aspect of this project is to study different sample handling methods for number based aerosol measurements, specifically, two different methods for removing volatile organic compounds (VOCs) from an aerosol sample. One method is a Dekati Thermodenuder (TD) and the other is an evaporative chamber/diluter (EvCh). These sample handling methods have been implemented for this project in an engine test cell built around a direct injection spark ignited (DISI) engine. The engine was designed for stoichiometric, homogeneous combustion. Direct injection is of particular interest for improved fuel efficiency but this comes with the production of a significant amount of (PM) and may therefore be subject to the proposed number based regulation. Another aspect of this project is to characterize PM from this engine in terms of particle number and composition. The first interesting observation is that PM number distributions, acquired using a TSI SMPS, have a large accumulation mode (30-294 nm) but a very small nuclei mode (8-30 nm). This is understood to represent a lack of condensation particles meaning that neither the exhaust conditions nor the sample handling conditions are conducive to condensation. This lack of nuclei mode does not, however, represent a lack of VOCs in the sample. It has been observed, using mass spectral analysis (limited to PM>50 nm), that PM from the DISI engine has approximately 40% organic content through varying operating conditions. This begs the question of how effective different sample handling methods are at removing these VOCs. For one specific operating condition, called Cold Start, the un-treated PM was 40% organic. The TD

  17. Impact of activated sludge configuration and operating conditions on in vitro and in vivo responses and trace organic compound removal.

    PubMed

    Parker, W J; Pileggi, V; Seto, P; Chen, X; Ogunlaja, M; Van Der Kraak, G; Parrott, J

    2014-08-15

    This study tested municipal sewage effluents generated at the pilot scale using conventional activated sludge (CAS), nitrifying activated sludge (CAS-N) and biological nutrient removal (BNR) in terms of the removal of trace organic compounds (TrOCs) and final effluent quality as indicated by yeast estrogenicity screening (YES), short term zebrafish reproduction and fathead minnow life-cycle tests. Under cold weather conditions (extended SRTs), the BNR configuration reduced the concentrations of the largest number of TrOCs while under warm weather conditions (reduced SRTs) the CAS-N was most effective. By comparison, YES test results indicated statistically lower responses in the BNR effluent in the warm weather tests and no difference between the effluents of CAS-N and BNR in the cold weather tests. Short term tests with adult zebrafish revealed no impact of the BNR and CAS-N effluents on egg production. By contrast egg production and gene expression in the CAS-exposed zebrafish were substantially less than that of control exposures and were similar to that of exposures to ammonia at similar concentrations as the CAS exposures. In fathead minnow life-cycle tests, exposures to CAS effluent (70-50% v/v) resulted in considerable mortality, reduced growth and reduced egg production that was likely due to the elevated ammonia concentrations. The CAS-N effluent (100% v/v) also resulted in some mortality and reduced growth and egg production in the fathead minnows. By contrast, the BNR effluent (100% v/v) had no effect on mortality, growth or egg production. The results suggest that enhancements to wastewater treatment plants that are associated with improved nitrogen removal can result in enhanced removal of TrOCs and can reduce the harmful effects of the effluents on aquatic biota. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Effectiveness of photocatalytic filter for removing volatile organic compounds in the heating, ventilation, and air conditioning system.

    PubMed

    Yu, Kuo-Pin; Lee, Grace Whei-May; Huang, Wei-Ming; Wu, Chih-Cheng; Lou, Chia-ling; Yang, Shinhao

    2006-05-01

    Nowadays, the heating, ventilation, and air conditioning (HVAC) system has been an important facility for maintaining indoor air quality. However, the primary function of typical HVAC systems is to control the temperature and humidity of the supply air. Most indoor air pollutants, such as volatile organic compounds (VOCs), cannot be removed by typical HVAC systems. Thus, some air handling units for removing VOCs should be added in typical HVAC systems. Among all of the air cleaning techniques used to remove indoor VOCs, photocatalytic oxidation is an attractive alternative technique for indoor air purification and deodorization. The objective of this research is to investigate the VOC removal efficiency of the photocatalytic filter in a HVAC system. Toluene and formaldehyde were chosen as the target pollutants. The experiments were conducted in a stainless steel chamber equipped with a simplified HVAC system. A mechanical filter coated with Degussa P25 titania photocatalyst and two commercial photocatalytic filters were used as the photocatalytic filters in this simplified HVAC system. The total air change rates were controlled at 0.5, 0.75, 1, 1.25, and 1.5 hr(-1), and the relative humidity (RH) was controlled at 30%, 50%, and 70%. The ultraviolet lamp used was a 4-W, ultraviolet-C (central wavelength at 254 nm) strip light bulb. The first-order decay constant of toluene and formaldehyde found in this study ranged from 0.381 to 1.01 hr(-1) under different total air change rates, from 0.34 to 0.433 hr(-1) under different RH, and from 0.381 to 0.433 hr(-1) for different photocatalytic filters.

  19. Evaluation of ozone generation and indoor organic compounds removal by air cleaners based on chamber tests

    NASA Astrophysics Data System (ADS)

    Yu, Kuo-Pin; Lee, Grace Whei-May; Hsieh, Ching-Pei; Lin, Chi-Chi

    2011-01-01

    Ozone can cause many health problems, including exacerbation of asthma, throat irritation, cough, chest ache, shortness of breath, and respiratory infections. Air cleaners are one of the sources of indoor ozone, and thus the evaluation of ozone generated by air cleaners is desired significant issue. Most evaluation methods proposed are based on chamber tests. However, the adsorption and desorption of ozone on the wall of test chamber and the deposition of ozone resulted from the surface reaction can influence the evaluation results. In this study, we developed a mass balance model that took the adsorption, desorption and deposition of ozone into consideration to evaluate the effective ozone emission rates of six selected air cleaners. The experiments were conducted in a stainless steel chamber with a volume of 11.3 m 3 at 25 °C and 60% relative humidity. The adsorption, desorption and deposition rate constants of ozone obtained by fitting the model to the experimental data were k a = 0.149 ± 0.052 m h -1, k d = 0.013 ± 0.007 h -1, and k r = 0.050 ± 0.020 h -1, respectively. The effective ozone emission rates of Air Cleaners No. 1, 2, and 3 ranged between 13,400-24,500 μg h -1, 7190-10,400 μg h -1, and 4880-6560 μg h -1, respectively, which were more stable than those of No.4, 5, and 6. The effective ozone emission rates of Air Cleaners No. 4, 5, and 6 increased with the time of operation which might be relevant to the decrease of ozone removal by the "aging" filter installed in these cleaners. The removal of toluene and formaldehyde by these six air cleaners were also evaluated and the clean air delivery rates (CADRs) of these two pollutants ranged from non-detectable to 0.42 ± 0.08 m 3 h -1, and from non-detectable to 0.75 ± 0.07 m 3 h -1, respectively. The CADRs showed an insignificant relationship with the effective ozone emission rates. Thus, the removal of toluene and formaldehyde might be resulted from the adsorption on the filters and the

  20. Removal of organic compounds from water by using a gold nanoparticle-poly(dimethylsiloxane) nanocomposite foam.

    PubMed

    Gupta, Ritu; Kulkarni, Giridhar U

    2011-06-20

    A low density, highly compressible, porous foam of poly(dimethylsiloxane) (PDMS) incorporated with Au nanoparticles (10-50 nm) has been synthesized by using a single-step process with water as a medium. It exhibits high swelling ability (≈600%) against benzene, toluene, ethylbenzene, and xylene (BTEX)-a property that has been exploited in the removal of oil spills from water. It is resistant to harsh chemical environments. It is also effective against odorous sulfur containing contaminants such as thioanisole. It works repeatedly and efficiently over many cycles. The regeneration of the foam is rather simple: heating in air to 300 °C for short time brings back its original activity. The fascinating properties of Au nanoparticles could be mingled with those of PDMS to provide a sustainable and practical solution for water treatment. It is also demonstrated to work effectively for deodorizing garlic extract with a promise as a food packaging material.

  1. Cu-based metal-organic framework/activated carbon composites for sulfur compounds removal

    NASA Astrophysics Data System (ADS)

    Fan, Hui-Ling; Shi, Rui-Hua; Zhang, Zhen-Rong; Zhen, Tian; Shangguan, Ju; Mi, Jie

    2017-02-01

    MOF-199 was modified by incorporating activated carbon (AC) during its synthesis under hydrothermal conditions to improve its performance in the removal of hydrogen sulfide (H2S) and dimethyl sulfide (CH3SCH3). A variety of different characterization techniques including X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, nitrogen adsorption/desorption isotherms, scanning electron microscopy (SEM), pyridine adsorption infrared spectroscopy (Py-IR), thermogravimetric- mass spectroscopy (TG-MS) and X-ray photoelectron spectroscopy (XPS) were used to analyze the fresh and exhausted composites. It was found that the composites, which have an amount of AC of less than 2%, had the same morphology as those of pristine MOF-199, but exhibited a more ordered crystallinity structure as well as higher surface area. The composite with 2% AC incorporation showed highest sulfur capacity of 8.46 and 8.53% for H2S and CH3SCH3, respectively, which increased by 51 and 41% compared to that of MOF-199. This improvement was attributed to the formation of more micropores and especially the increased number of unsaturated copper metal sites, as revealed by Py-IR. It is suggested the chemical reaction was apparent during adsorption of H2S, which resulted in the formation of CuS and the collapse of the MOF structure. Whereas reversible chemisorption was found for CH3SCH3 adsorption, as testified by TG-MS and fixed-bed regeneration. Exhausted MAC-2 can be almost totally regenerated by high temperature 180 °C nitrogen purge, indicating a promising adsorbent for CH3SCH3 removal.

  2. Decolourization and removal of some organic compounds from olive mill wastewater by advanced oxidation processes and lime treatment.

    PubMed

    Uğurlu, Mehmet; Kula, Ibrahim

    2007-07-01

    Olive mill wastewater (OMW) generated by the olive oil extracting industry is a major pollutant, because of its high organic load and phytotoxic and antibacterial phenolic compounds which resist biological degradation. Mediterranean countries are mostly affected by this serious environmental problem since they are responsible for 95% of the worldwide olive-oil production. There are many methods used for OMW treatment, such as adsorption, electro coagulation, electro-oxidation, biological degradation, advanced oxidation processes (AOPs), chemical coagulation, flocculation, filtration, lagoons of evaporation and burning systems, etc. Currently, there is no such economical and easy solution. The aim of this study was to evaluate the feasibility of decolourization and removal of phenol, lignin, TOC and TIC in OMW by UV/H2O2 (AOPs). The operating parameters, such as hydrogen peroxide dosage, times, pH, effect of UV and natural sunlight were determined to find the suitable operating conditions for the best removal. Moreover, there is no study reported in the literature related to the use of OMW was obtained from an olive-oil producing plant (Muğla area of Turkey) which uses a modern production process. No chemical additives are used during olive oil production. This study was realised by using two different UV sources, while taking the time and energy consumption into consideration. These two sources were mercury lamps and natural sunlight. Before starting AOPs experiments, one litre of OMW was treated by adding lime until a pH of 7.00. Then, 100 ml was taken from each sample, and 1 to 10 ml of a 30% H2O2 (Riedel-deHaen) solution was added. These solutions in closed vessels were laid in the natural sunlight for a week and their compositions and colour changes were analysed daily by UV-Vis spectrophotometer. At the end of the one-week period, they were treated with lime. In this study, the effect of changes in the initial pH, times and H2O2 concentrations on removal was

  3. Removal of aliphatic amino acids by hybrid organic inorganic layered compounds

    NASA Astrophysics Data System (ADS)

    Silverio, Fabiano; dos Reis, Márcio José; Tronto, Jairo; Valim, João Barros

    2007-04-01

    Amino acids have been extensively used in several processes of the pharmaceutical and food industries. Treatments for the recovery and reuse of the wastewaters generated from these processes are few and little known. This work aims at studying the influence of variables like temperature, pH and ionic strength on the adsorption of the amino acids Asp and Glu, contained in aqueous solutions, on layered double hydroxides of the Mg-Al-CO 3-LDH system. The adsorption experiments were performed at two different temperatures (298 and 310 K), two different pH values (7.0 and 10.0), and two ionic strength conditions (with or without the addition of NaCl). The adsorption isotherms exhibited similar profiles under the various conditions studied: an increase in temperature as well as an increase in the pH value decreased the amount of adsorbed amino acid while an increase in the ionic strength increased Asp and Glu adsorption. The PXRD analysis showed that the diffractograms obtained before and after the adsorption of amino acids have a similar pattern. The FT-IR spectra of the adsorbed material presented specific bands, which are related to the amino acids. The concentration range varied up to the anion solubility product and the extraction rate lay between 2.7 and 23.4% at higher equilibrium concentrations, showing that Mg-Al-CO 3-LDH is efficient at removing the amino acids from the aqueous medium.

  4. Removal of volatile organic compounds from air streams by making use of a microwave plasma burner with reverse vortex flows

    NASA Astrophysics Data System (ADS)

    Kim, Ji H.; Ma, Suk H.; Cho, Chang H.; Hong, Yong C.; Ahn, Jae Y.

    2014-01-01

    We developed an atmospheric-pressure microwave plasma burner for removing volatile organic compounds (VOCs) from polluted air streams. This study focused on the destruction of the VOCs in the high flow rate polluted streams required for industrial use. Plasma flames were sustained by injecting liquefied natural gas (LNG), which is composed of CH4, into the microwave plasma torch. With its high temperature and high density of atomic oxygen, the microwave torch attained nearly complete combustion of LNG, thereby providing a large-volume, high-temperature plasma flame. The plasma flame was applied to reactors in which the polluted streams were in one of two vortex flows: a conventional vortex reactor (CVR) or a reverse vortex reactor (RVR). The RVR, using a plasma power of 2 kW and an LNG flow of 20 liters per minute achieved a destruction removal efficiency (DRE) of 98% for an air flow rate of 5 Nm3/min polluted with 550 pm of VOCs.. For the same experimental parameters, the CVR provided a DRE of 90.2%. We expect that this decontamination system will prove effective in purifying contaminated air at high flow rates.

  5. Removal mechanisms in aerobic slurry bioreactors for remediation of soils and sediments polluted with hydrophobic organic compounds: An overview.

    PubMed

    Pino-Herrera, Douglas O; Pechaud, Yoan; Huguenot, David; Esposito, Giovanni; van Hullebusch, Eric D; Oturan, Mehmet A

    2017-10-05

    Hydrophobic organic compound (HOC)-contaminated soils are a great environmental and public health concern nowadays. Further research is necessary to develop environmental friendly biotechnologies that allows public and private sectors to implement efficient and adaptable treatment approaches. Aerobic soil-slurry bioreactor technology has emerged as an effective and feasible technique with a high remediation potential, especially for silt and clay soil fractions, which often contain the highest pollutant concentration levels and are usually difficult to remove by implementing conventional methods. However, the mechanisms involved in the HOC removal in bioslurry reactor are still not completely understood. Gas-liquid and solid-liquid mass transfer, mass transport and biodegradation phenomena are the main known processes taking place in slurry bioreactors. This review compiles the most up-to-date information available about these phenomena and tries to link them, enlightening the possible interactions between parameters. It gathers the basic information needed to understand the complex bioremediation technology and raises awareness of some considerations that should be made. Copyright © 2017. Published by Elsevier B.V.

  6. Energy Efficient Removal of Volatile Organic Compounds (VOCs) and Organic Hazardous Air Pollutants (o-HAPs) from Industrial Waste Streams by Direct Electron Oxidation

    SciTech Connect

    Testoni, A. L.

    2011-10-19

    This research program investigated and quantified the capability of direct electron beam destruction of volatile organic compounds and organic hazardous air pollutants in model industrial waste streams and calculated the energy savings that would be realized by the widespread adoption of the technology over traditional pollution control methods. Specifically, this research determined the quantity of electron beam dose required to remove 19 of the most important non-halogenated air pollutants from waste streams and constructed a technical and economic model for the implementation of the technology in key industries including petroleum refining, organic & solvent chemical production, food & beverage production, and forest & paper products manufacturing. Energy savings of 75 - 90% and green house gas reductions of 66 - 95% were calculated for the target market segments.

  7. Effectiveness of three configurations of membrane bioreactors on the removal of priority and emergent organic compounds from wastewater: comparison with conventional wastewater treatments.

    PubMed

    Camacho-Muñoz, D; Martín, J; Santos, J L; Alonso, E; Aparicio, I; De la Torre, T; Rodriguez, C; Malfeito, J J

    2012-05-01

    In this work the effectiveness of membrane bioreactors as advanced treatment on the removal of emergent and priority organic compounds in wastewater treatment plants has been evaluated during a one-year monitoring study. The studied wastewater treatment plant operates with flat sheet and hollow fibre membranes in two parallel lines. Moreover, a reverse osmosis module connected in series after the hollow fibre membrane was evaluated for one month. Comparison of membrane bioreactor and conventional activated sludge treatment was also investigated, as well as the influence of the physicochemical properties of the compounds on the removal rates achieved. Sixteen pharmaceutical compounds belonging to seven therapeutic groups and eight priority organic pollutants, including linear alkylbenzene sulfonates, nonylphenol and its ethoxylates and phthalate, were monitored. The highest mean concentrations corresponded to priority organic pollutants (309 μg L(-1) of linear alkylbenzene sulfonate C(12)) followed by pharmaceutical compounds (24.5 μg L(-1) of ibuprofen). No significant difference of effectiveness was found among flat sheet and hollow fibre membranes. However, an improvement was obtained with the addition of a reverse osmosis module for most of the compounds. Biodegradation has been shown as the main route involved in the removal of organic compounds during both technologies.

  8. Particulate Matter Sampling and Volatile Organic Compound Removal for Characterization of Spark Ignited Direct Injection Engine Emissions

    SciTech Connect

    Matthias, Nicholas; Farron, Carolyn; Foster, David E.; Andrie, Michael; Krieger, Roger; Najt, Paul; Narayanaswamy, Kushal; Solomon, Arun; Zelenyuk, Alla

    2011-08-30

    More stringent emissions regulations are continually being proposed to mitigate adverse human health and environmental impacts of internal combustion engines. With that in mind, it has been proposed that vehicular particulate matter (PM) emissions should be regulated based on particle number in addition to particle mass. One aspect of this project is to study different sample handling methods for number based aerosol measurements, specifically, two different methods for removing volatile organic compounds (VOCs). One method is a thermodenuder (TD) and the other is an evaporative chamber/diluter (EvCh). These sample handling methods have been implemented in an engine test cell with a spark ignited direct injection (SIDI) engine. The engine was designed for stoichiometric, homogeneous combustion. SIDI is of particular interest for improved fuel efficiency compared to other SI engines, however, the efficiency benefit comes with greater PM emissions and may therefore be subject to the proposed number based PM regulation. Another aspect of this project is to characterize PM from this engine in terms of particle number and composition

  9. Particulate Matter Sampling and Volatile Organic Compound Removal for Characterization of Spark Ignited Direct Injection Engine Emissions

    SciTech Connect

    Matthias, Nicholas; Farron, Carrie; Foster, David E.; Andrie, Michael; Krieger, Roger; Najt, Paul M.; Narayanaswamy, Kushal; Solomon, Arun S.; Zelenyuk, Alla

    2012-01-01

    More stringent emissions regulations are continually being proposed to mitigate adverse human health and environmental impacts of internal combustion engines. With that in mind, it has been proposed that vehicular particulate matter (PM) emissions should be regulated based on particle number in addition to particle mass. One aspect of this project is to study different sample handling methods for number based aerosol measurements, specifically, two different methods for removing volatile organic compounds (VOCs). One method is a thermodenuder (TD) and the other is an evaporative chamber/diluter (EvCh). These sample handling methods have been implemented in an engine test cell with a spark ignited direct injection (SIDI) engine. The engine was designed for stoichiometric, homogeneous combustion. SIDI is of particular interest for improved fuel efficiency compared to other SI engines, however, the efficiency benefit comes with greater PM emissions and may therefore be subject to the proposed number based PM regulation. Another aspect of this project is to characterize PM from this engine in terms of particle number and composition.

  10. Tricrystalline TiO2 with enhanced photocatalytic activity and durability for removing volatile organic compounds from indoor air.

    PubMed

    Chen, Kunyang; Zhu, Lizhong; Yang, Kun

    2015-06-01

    It is important to develop efficient and economic techniques for removing volatile organic compounds (VOCs) in indoor air. Heterogeneous TiO2-based semiconductors are a promising technology for achieving this goal. Anatase/brookite/rutile tricrystalline TiO2 with mesoporous structure was synthesized by a low-temperature hydrothermal route in the presence of HNO3. The obtained samples were characterized by X-ray diffraction and N2 adsorption-desorption isotherm. The photocatalytic activity was evaluated by photocatalytic decomposition of toluene in air under UV light illumination. The results show that tricrystalline TiO2 exhibited higher photocatalytic activity and durability toward gaseous toluene than bicrystalline TiO2, due to the synergistic effects of high surface area, uniform mesoporous structure and junctions among mixed phases. The tricrystalline TiO2 prepared at RHNO3=0.8, containing 80.7% anatase, 15.6% brookite and 3.7% rutile, exhibited the highest photocatalytic activity, about 3.85-fold higher than that of P25. The high activity did not significantly degrade even after five reuse cycles. In conclusion, it is expected that our study regarding gas-phase degradation of toluene over tricrystalline TiO2 will enrich the chemistry of the TiO2-based materials as photocatalysts for environmental remediation and stimulate further research interest on this intriguing topic.

  11. Volatile Organic Compound (VOC) Removal by Vapor Permeation at Low VOC Concentrations: Laboratory Scale Results and Modeling for Scale Up

    PubMed Central

    Rebollar-Perez, Georgette; Carretier, Emilie; Lesage, Nicolas; Moulin, Philippe

    2011-01-01

    Petroleum transformation industries have applied membrane processes for solvent and hydrocarbon recovery as an economic alternative to reduce their emissions and reuse evaporated components. Separation of the volatile organic compounds (VOCs) (toluene-propylene-butadiene) from air was performed using a poly dimethyl siloxane (PDMS)/α-alumina membrane. The experimental set-up followed the constant pressure/variable flow set-up and was operated at ∼21 °C. The membrane is held in a stainless steel module and has a separation area of 55 × 10−4 m2. Feed stream was set to atmospheric pressure and permeate side to vacuum between 3 and 5 mbar. To determine the performance of the module, the removed fraction of VOC was analyzed by Gas Chromatography/Flame Ionization Detector (GC/FID). The separation of the binary, ternary and quaternary hydrocarbon mixtures from air was performed at different flow rates and more especially at low concentrations. The permeate flux, permeance, enrichment factor, separation efficiency and the recovery extent of the membrane were determined as a function of these operating conditions. The permeability coefficients and the permeate flux through the composite PDMS-alumina membrane follow the order given by the Hildebrand parameter: toluene > 1,3-butadiene > propylene. The simulated data for the binary VOC/air mixtures showed fairly good agreement with the experimental results in the case of 1,3-butadiene and propylene. The discrepancies observed for toluene permeation could be minimized by taking into account the effects of the porous support and an influence of the concentration polarization. Finally, the installation of a 0.02 m2 membrane module would reduce 95% of the VOC content introduced at real concentration conditions used in the oil industry. PMID:24957498

  12. The effects of magnetic field on the removal of organic compounds and metals by coagulation and flocculation

    NASA Astrophysics Data System (ADS)

    Duangduen, C.; Nathaporn, A.; Kitiphatmontree, M.

    2006-09-01

    The effects of magnetic field (MF) were studied using surface water from the Pra Ram IX reservoir. Dissolved organic carbon (DOC) removal was improved by exposure of untreated water to MF for up to 5 hours duration. MF was found to alter the physico-chemical properties of some involved substances. Optimum DOC removal (15-20%) was observed after 30-40 minutes of exposure. Flocculation was also improved in the presence of MF. The removal of DOC, iron, heavy metals (As, Zn) was the best with an optimum ferric chloride dosage of 50 mg/L and exposure to 0.35Tesla magnetic field for 30 min. However, Ca removal was not affected by this treatment.

  13. Simultaneous removal of color, organic compounds and nutrients in azo dye-containing wastewater using up-flow constructed wetland.

    PubMed

    Ong, Soon-An; Uchiyama, Katsuhiro; Inadama, Daisuke; Yamagiwa, Kazuaki

    2009-06-15

    Combination of aerobic and anaerobic processes in constructed wetlands can enhance the treatment performance in textile wastewater. This study assessed the treatment of azo dye Acid Orange 7 (AO7) and nutrients using five laboratory-scale up-flow constructed wetlands (UFCW) with and without supplementary aeration, and with different emergent plants. Supplementary aeration controlled the size of aerobic and anaerobic zones in the UFCW reactors as evidenced by the oxidation-reduction potential (ORP) and dissolved oxygen (DO) profile of the UFCW. The AO7 removal efficiency was above 95% in all UFCW reactors and most of the color was extensively removed in the anaerobic region of the UFCW beds. The intermediates produced through the breakage of azo bond were significantly reduced in the UFCW reactors with supplementary aeration. The results indicated the applicability of the UFCW reactors to the treatment of azo dye-containing wastewater. The removals of T-N and T-P were in the range of 60-67% and 26-37%, respectively, among the UFCW reactors. The COD and NH(4)-N removals in the aerated reactors were about 86 and 96%, respectively. On the other hand, the COD and NH(4)-N removals were in the range of 78-82% and 41-48%, respectively, in the non-aerated reactors. The supplementary aeration enhanced the removal efficiencies in organic matter, NH(4)-N and aromatic amines in the UFCW reactors.

  14. Assessment of biostimulation and bioaugmentation for removing chlorinated volatile organic compounds from groundwater at a former manufacture plant.

    PubMed

    Zhang, Shu; Hou, Zhen; Du, Xiao-Ming; Li, Dong-Ming; Lu, Xiao-Xia

    2016-11-01

    Site in a former chemical manufacture plant in China was found contaminated with high level of chlorinated volatile organic compounds (CVOCs). The major contaminants chloroform (CF), 1,2-dichloroethane (1,2-DCA) and vinyl chloride (VC) in groundwater were up to 4.49 × 10(4), 2.76 × 10(6) and 4.35 × 10(4) μg/L, respectively. Ethene and methane were at concentrations up to 2219.80 and 165.85 μg/L, respectively. To test the hypothesis that the CVOCs in groundwater at this site could be removed via biodegradation, biomarker analyses and microcosm studies were conducted. Dehalococcoides 16S rRNA gene and VC-reductase gene vcrA at densities up to 1.5 × 10(4) and 3.2 × 10(4) copies/L were detected in some of the groundwater samples, providing strong evidence that dechlorinating bacteria were present in the aquifer. Results from the microcosm studies showed that at moderate concentrations (CF about 4000 μg/L and 1,2-DCA about 100 μg/L), CF was recalcitrant under natural condition but was degraded under biostimulation and bioaugmentation, while 1,2-DCA was degraded under all the three conditions. At high concentration (CF about 1,000,000 μg/L and 1,2-DCA about 20,000 μg/L), CF was recalcitrant under all the three treatments and 1,2-DCA was only degraded under bioaugmentation, indicating that high concentrations of contaminants were inhibitory to the bacteria. Electron donors had influence on the degradation of contaminants. Of the four fatty acids (pyruvate, acetate, propionate and lactate) examined, all could stimulate the degradation of 1,2-DCA at both moderate and high concentrations, whereas only pyruvate and acetate could stimulate the degradation of CF at moderate concentration. In the microcosms, the observed first-order degradation rates of CF and 1,2-DCA were up to 0.12 and 0.11/day, respectively. Results from the present study provided scientific basis for remediating CVOCs contaminated groundwater at the site.

  15. Organic compounds removal and toxicity reduction of landfill leachate by commercial bakers' yeast and conventional bacteria based membrane bioreactor integrated with nanofiltration.

    PubMed

    Reis, Beatriz Gasparini; Silveira, Amanda Lemes; Tostes Teixeira, Luiza Procópio; Okuma, Adriana Akemi; Lange, Liséte Celina; Amaral, Miriam Cristina Santos

    2017-09-30

    This study aimed to compare the performance of a commercial bakers' yeast (MBRy) and conventional bacteria (MBRb) based membrane bioreactor integrated with nanofiltration (NF) in the removal of landfill leachate toxicity. Performances were evaluated using physicochemical analyses, toxicity tests and identification of organic compounds. The MBRb and MBRy were operated with a hydraulic retention time (HRT) of 48h and solids retention time (SRT) of 60 d. The MBRy demonstrated better removal efficiencies for COD (69±7%), color (54±11%) and ammoniacal nitrogen (34±7%) compared to MBRb, which showed removal efficiencies of 27±5%, 33±4% and 27±7%, for COD, color and ammoniacal nitrogen. Although the MBRy seems to be the configuration that presented the highest efficiency; it generated toxic permeate whose toxicity cannot be explained by physicochemical results. The identification of compounds shows that there is a wide range of compounds in the landfill leachate in addition to others that are produced in the biological treatment steps. The NF plays a crucial role in the polishing of the final effluents by the either complete or partial retention of compounds, that attribute toxicity to the leachate, and inorganic contaminants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Microbial removal of organic sulfur from coal (bacterial degradation of sulfur-containing heterocyclic compounds): Final report, March 1--December 31, 1987

    SciTech Connect

    Klubek, B.; Clark, D.

    1988-03-01

    The presence of levels of sulfur in coal is a major source of air pollution and considerable efforts are being made to devise a cost-effective way of removing it. One promising method is microbial desulfurization. Almost all of the inorganic sulfur can be removed from coal by the bacteria Thiobacillus or Sulfolobus, which convert sulfide to sulfate but leave the organic sulfur untouched. If strains of bacteria are developed which remove organic sulfur from coal and are used in conjunction with inorganic sulfur-oxidizing bacteria, the result should be an effective desulfurization method. We are using two approaches to develop bacteria which remove organic sulfur. One method is to mutate a laboratory species, Escherichia coli, an organism which is genetically well understood and whose pathways for the metabolism of sulfur-containing amino acids have been extensively investigated. Such thiophene degraders can be genetically analyzed, and the genes involved can be cloned in order to amplify their products. The second approach is the development of naturally occurring bacteria capable of thiophene degradation. Enrichment culture techniques, mutagenesis of current isolated strains, and mixed culture studies with crushed coal comprise an alternative approach in our study. The degradation rates of our model-thiophene compounds and the preliminary testing of our isolates with coal will index the efficiency of our strains in coal desulfurization. Ultimately, the genes responsible for thiophene degradation by our isolated strains will be transferred to our E. coli strain, creating a single organism capable of degrading a broad spectrum of thiophene compounds. 14 refs., 5 tabs.

  17. Thermodynamics of Organic Compounds

    DTIC Science & Technology

    1979-01-01

    General Techniques for Combustion of Liquid/Soli. Organic Compounds by Oxygen Bomb Calorimetry by Arthur J. Head, William D. Good, and Ccrnelius...Mosselman, Chap. 8; Combustion of Liquid/Solid Organic Compounds with Non-Metallic Hetero-Atoms by Arthur J. Head and William D. Good, Chap. 9; in...0 Box 95085 Washington, DC 20234 Los Angeles, CA 90045 National Bureau of Standards CINDAS Chemical Thermodynamics Division Purdue University

  18. Removal of organic compounds and trace metals from oil sands process-affected water using zero valent iron enhanced by petroleum coke.

    PubMed

    Pourrezaei, Parastoo; Alpatova, Alla; Khosravi, Kambiz; Drzewicz, Przemysław; Chen, Yuan; Chelme-Ayala, Pamela; Gamal El-Din, Mohamed

    2014-06-15

    The oil production generates large volumes of oil sands process-affected water (OSPW), referring to the water that has been in contact with oil sands or released from tailings deposits. There are concerns about the environmental impacts of the release of OSPW because of its toxicity. Zero valent iron alone (ZVI) and in combination with petroleum coke (CZVI) were investigated as environmentally friendly treatment processes for the removal of naphthenic acids (NAs), acid-extractable fraction (AEF), fluorophore organic compounds, and trace metals from OSPW. While the application of 25 g/L ZVI to OSPW resulted in 58.4% removal of NAs in the presence of oxygen, the addition of 25 g petroleum coke (PC) as an electron conductor enhanced the NAs removal up to 90.9%. The increase in ZVI concentration enhanced the removals of NAs, AEF, and fluorophore compounds from OSPW. It was suggested that the electrons generated from the oxidation of ZVI were transferred to oxygen, resulting in the production of hydroxyl radicals and oxidation of NAs. When OSPW was de-oxygenated, the NAs removal decreased to 17.5% and 65.4% during treatment with ZVI and CZVI, respectively. The removal of metals in ZVI samples was similar to that obtained during CZVI treatment. Although an increase in ZVI concentration did not enhance the removal of metals, their concentrations effectively decreased at all ZVI loadings. The Microtox(®) bioassay with Vibrio fischeri showed a decrease in the toxicity of ZVI- and CZVI-treated OSPW. The results obtained in this study showed that the application of ZVI in combination with PC is a promising technology for OSPW treatment.

  19. Organic compounds in meteorites

    NASA Technical Reports Server (NTRS)

    Anders, E.; Hayatsu, R.; Studier, M. H.

    1973-01-01

    The problem of whether organic compounds originated in meteorites as a primary condensate from a solar gas or whether they were introduced as a secondary product into the meteorite during its residence in a parent body is examined by initially attempting to reconstruct the physical conditions during condensation (temperature, pressure, time) from clues in the inorganic matrix of the meteorite. The condensation behavior of carbon under these conditions is then analyzed on the basis of thermodynamic calculations, and compounds synthesized in model experiments on the condensation of carbon are compared with those actually found in meteorites. Organic compounds in meteorites seem to have formed by catalytic reactions of carbon monoxide, hydrogen, and ammonia in the solar nebula at 360 to 400 K temperature and about 3 to 7.6 microtorr pressure. The onset of these reactions was triggered by the formation of suitable catalysts (magnetite, hydrated silicates) at these temperatures.

  20. Organic compounds in meteorites

    NASA Technical Reports Server (NTRS)

    Anders, E.; Hayatsu, R.; Studier, M. H.

    1973-01-01

    The problem of whether organic compounds originated in meteorites as a primary condensate from a solar gas or whether they were introduced as a secondary product into the meteorite during its residence in a parent body is examined by initially attempting to reconstruct the physical conditions during condensation (temperature, pressure, time) from clues in the inorganic matrix of the meteorite. The condensation behavior of carbon under these conditions is then analyzed on the basis of thermodynamic calculations, and compounds synthesized in model experiments on the condensation of carbon are compared with those actually found in meteorites. Organic compounds in meteorites seem to have formed by catalytic reactions of carbon monoxide, hydrogen, and ammonia in the solar nebula at 360 to 400 K temperature and about 3 to 7.6 microtorr pressure. The onset of these reactions was triggered by the formation of suitable catalysts (magnetite, hydrated silicates) at these temperatures.

  1. Enhanced removal of organics by permanganate preoxidation using tannic acid as a model compound--role of in situ formed manganese dioxide.

    PubMed

    Zhang, Lizhu; Ma, Jun; Li, Xin; Wang, Shutao

    2009-01-01

    The effect of permanganate preoxidation on organic matter removal during the coagulation with aluminum chloride was investigated using tannic acid as a model compound. Results showed that a small amount of KMnO4 (0.75 mg/L) increased the removal efficiency of tannic acid up to 20%, as compared to the process of coagulation by aluminum chloride alone. The key factor enhancing the removal efficiency of tannic acid in preoxidation process was the in situ formation of a reductant manganese dioxide. The complexation model was used to describe the reaction between MnO2 and tannic acid. Under weak pH condition, tannic acid was difficult to be adsorbed by MnO2 due to the static electrical repulsive forces. The presence of Ca2+ served as a bridge to hold the negative charged MnO2 and tannic acid together, which could be a crucial factor influencing tannic acid adsorption by in-situ manganese dioxide.

  2. Thermodynamics of Organic Compounds

    DTIC Science & Technology

    1981-01-01

    Organic Compounds by I A. Hossenlopp and D. W. Scott -- Journal of Chemical Thermodynamics , 13, No. 5, 405-414 (1981). t 1 I- i !I *1 I I ~ I [LI...National Bureau of Standards CINDAS Chemical Thermodynamics Division Purdue University Research Park Attn: Dr Stan Abramowitz Attn: Dr H H Li Mr David... Chemical Thermodynamics Division AFAOL/RJT (Dr 7 D Stull) Attn: Mr Donald D Wagman Wright-Patterson AFB, OH 45433 Washington, DC 20234 U.S. Army

  3. Removal of organic compounds from water via cloud-point extraction with permethyl hydroxypropyl-[beta]-cyclodextrin

    SciTech Connect

    Warner-Schmid, D.; Hoshi, Suwaru; Armstrong, D.W. )

    1993-03-01

    Aqueous solutions of nonionic surfactants are known to undergo phase separations at elevated temperatures. This phenomenon is known as clouding,' and the temperature at which it occurs is refereed to as the cloud point. Permethylhydroxypropyl-[beta]-cyclodextrin (PMHP-[beta]-CD) was synthesized and aqueous solutions containing it were found to undergo similar cloud-point behavior. Factors that affect the phase separation of PMHP-[beta]-CD were investigated. Subsequently, the cloud-point extractions of several aromatic compounds (i.e., acetanilide, aniline, 2,2[prime]-dihydroxybiphenyl, N-methylaniline, 2-naphthol, o-nitroaniline, m-nitroaniline, p-nitroaniline, nitrobenzene, o-nitrophenol, m-nitrophenol, p-nitrophenol, 4-phenazophenol, 3-phenylphenol, and 2-phenylbenzimidazole) from dilute aqueous solution were evaluated. Although the extraction efficiency of the compounds varied, most can be quantitatively extracted if sufficient PMHP-[beta]-CD is used. For those few compounds that are not extracted (e.g., o-nitroacetanilide), the cloud-point procedure may be an effective one-step isolation or purification method. 18 refs., 2 figs., 3 tabs.

  4. Strategies for Controlling and Removing Trace Organic Compounds Found in Potable Water Supplies at Fixed Army Installations

    DTIC Science & Technology

    1985-08-01

    The bed depth Is 6.9 ft, velocity is 11.1 ft/hr, and EBCT Is 37 min. The plant’s operation is completely automated . Carbon life is I to 2 years or...compounds and biological growth on the carbon, and is amenable to automation . Further testing is needed to optimize the size of carrier material and...72203 ATTNi Libary ATii Chief, Engr Div Tulsa 74102 Ft. selvoir, VA 32060 ATTH: Chief, Cngr Div ATTMI Learing Resources Center Fort worth 76102 ATNi

  5. The effect of ozone on the removal effectiveness of photocatalysis on indoor gaseous biogenic volatile organic compounds.

    PubMed

    Yu, Kuo-Pin; Lee, Grace Whei-may; Huang, Guo-Hao

    2010-07-01

    In this study, the degradation of d-limonene by photocatalytic oxidation (PCO) (titanium dioxide [TiO2]/ultraviolet [UV]) and by the combination of PCO and ozone (O3) (TiO2/UV/O3) was investigated to evaluate the enhancement effect of O3. The degradation of d-limonene by UV/O3 was also investigated for comparison. The experiments were conducted with a quartz photoreactor under various gas flow rates (600-1600 mL min(-1)), d-limonene concentrations (0.5-9 parts per million [ppm]), and relative humidity (RH) (20-80%). The d-limonene removal efficiency of TiO2/UV/O3, TiO2/UV, and UV/O3 ranged from 62 to 99%, from 49 to 99%, and from 46 to 75%, respectively. The addition of 120-ppb O3 can enhance the d-limonene removal efficiency of PCO up to 12%. The apparent kinetic parameters (apparent rate constants, kapparent and Langmuir adsorption constants, Kapparent of TiO2/UV and TiO2/UV/O3 reactions obtained from fitting Langmuir-Hinshelwood models are TiO2/UV: kapparent = 1.45 x 10(-3) ppm-m sec(-1), Kapparent = 0.34 ppm(-1); TiO2/ UV/O3: kapparent = 1.83 x 10(-3) ppm-m sec(-1), and Kapparent = 0.35 ppm(-1). When RH was higher than 40%, the residual intermediates yield rates of d-limonene of TiO2/UV/O3, TiO2/UV, and UV/O3 reactions ranged from 0.39 to 0.51 micromol carbon m(-2) sec(-1), 0.56 to 1.96 micromol carbon m(-2) sec(-1), and 157 to 177 micromol carbon m(-3) sec(-1), respectively. In the photocatalytic reaction experiments, the addition of 120-parts per billion (ppb) O3 can reduce the residual intermediates yield rates of d-limonene by up to 1.46 micromol carbon m(-2) sec(-1). These experimental results showed that O3 can enhance the effectiveness of photocatalysis on the removal of d-limonene.

  6. Organic compounds in meteorites

    NASA Technical Reports Server (NTRS)

    Lawless, J. G.

    1980-01-01

    Recent studies of carbonaceous chondrites provide evidence that certain organic compounds are indigenous and the result of an abiotic, chemical synthesis. The results of several investigators have established the presence of amino acids and precursors, mono- and dicarboxylic acids, N-heterocycles, and hydrocarbons as well as other compounds. For example, studies of the Murchison and Murray meteorites have revealed the presence of at least 40 amino acids with nearly equal abundances of D and L isomers. The population consists of both protein and nonprotein amino acids including a wide variety of linear, cyclic, and polyfunctional types. Results show a trend of decreasing concentration with increasing carbon number, with the most abundant being glycine (41 n Moles/g). These and other results to be reviewed provide persuasive support for the theory of chemical evolution and provide the only natural evidence for the protobiological subset of molecules from which life on earth may have arisen.

  7. Graphene nanosheets as novel adsorbents in adsorption, preconcentration and removal of gases, organic compounds and metal ions.

    PubMed

    Yu, Jin-Gang; Yu, Lin-Yan; Yang, Hua; Liu, Qi; Chen, Xiao-Hong; Jiang, Xin-Yu; Chen, Xiao-Qing; Jiao, Fei-Peng

    2015-01-01

    Due to their high adsorption capacities, carbon-based nanomaterials such as carbon nanotubes, activated carbons, fullerene and graphene are widely used as the currently most promising functional materials. Since its discovery in 2004, graphene has exhibited great potential in many technological fields, such as energy storage materials, supercapacitors, resonators, quantum dots, solar cells, electronics, and sensors. The large theoretical specific surface area of graphene nanosheets (2630 m(2)·g(-1)) makes them excellent candidates for adsorption technologies. Further, graphene nanosheets could be used as substrates for decorating the surfaces of nanoparticles, and the corresponding nanocomposites could be applied as novel adsorbents for the removal of low concentrated contaminants from aqueous solutions. Therefore, graphene nanosheets will challenge the current existing adsorbents, including other types of carbon-based nanomaterials. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. On the performance of FAU and MFI zeolites for the adsorptive removal of a series of volatile organic compounds from air using molecular simulation.

    PubMed

    Calero, S; Gómez-Álvarez, P

    2015-10-21

    Volatile organic compound (VOC) emissions can cause serious risk to human health and the environment. In this work, we used Monte Carlo simulations to assess the performance of industrially important zeolites for the adsorption-based removal of a number of common air pollutants, particularly small saturated and unsaturated hydrocarbons: propane, butane, propene, and 1-butene. We focused on the cage-like FAU and channel-like MFI zeolites. The adsorption isotherms of the multicomponent N2/O2/Ar/VOC mixtures at real concentrations and room temperature reveal a considerable influence of the host topology and pore dimensions. While the adsorption of the VOCs from the mixture in FAU is almost negligible, it is remarkable in MFI. The adsorption selectivity of each VOC over the air compounds exhibits a maximum at about 10(6)-10(7) Pa, and then decreases to virtually zero due to entropic effects. This behaviour for selectivity is maintained regardless of the chain length and the presence of double bonds in the VOC, but the values are indeed affected. Also, we examined the selectivity at 10(7) Pa for a number of other widely used zeolites, with pore features ensuring the diffusion of the adsorbates. Apart from MFI, we also found the channel-like MEL and MTW zeolite candidates for the targeted air decontamination.

  9. Removal of organics from drinking water

    SciTech Connect

    Lykins, B.W.

    1988-01-01

    Organic contamination of drinking water is basically caused by two general classes of organics; man-made synthetic organics and disinfection of naturally occurring organics (disinfection by-products). Many volatile and non-volatile synthetic organics at trace concentrations are being detected in surface and ground waters. Contaminated ground water usually contains two or more predominant organic compounds and several other identifiable ones at lesser concentrations. Surface waters, such as rivers, generally contain many organic compounds in low concentrations. The document summarizes the treatment technologies that EPA's Drinking Water Research Division (DWRD) is evaluating for removal of VOCs, SOCs, and disinfection by-products from water supplies. Carbon adsorption is effective for removing both VOCs and SOCs. Packed-tower and diffused aeration are best suited for removing VOCs. Of the technologies that show promise and are being tested at the bench and pilot scales, conventional treatment with powdered activated carbon (PAC) is effective for removing a few of the SOCs, ozone oxidation is effective for removing certain classes of VOCs and SOCs, and certain reverse osmosis membranes and ultraviolet treatment are also potentially effective against VOCs and SOCs.

  10. Analyzing method on biogenic volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Bai, J. H.; Wang, M. X.; Hu, F.; Greenberg, J. P.; Guenther, A. B.

    2002-02-01

    In order to analyze biogenic volatile organic compounds in the atmosphere, an automated gas chromatography is developed and employed at the laboratory of National Center for Atmospheric Research (NCAR) during January to July, 2000. A small refrigerator was used so as to remove water in the air sample from gas line, and get accurate concentrations of volatile organic compounds. At 5degreesC, good water removing efficiency can be obtained at controlled flow rate. Air samples were collected around the building of Mesa Lab. of NCAR and analyzed by this gas chromatography system. This paper reports this gas chromatography system and results of air samples. The experimental results show that this gas chromatography system has a good reproducibility and stability, and main interesting volatile organic compounds such as isoprene, monoterpenes have an evident diurnal variation.

  11. Organic Compounds in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Cooper, Grorge

    2001-01-01

    Carbonaceous meteorites are relatively enriched in soluble organic compounds. To date, these compounds provide the only record available to study a range of organic chemical processes in the early Solar System chemistry. The Murchison meteorite is the best-characterized carbonaceous meteorite with respect to organic chemistry. The study of its organic compounds has related principally to aqueous meteorite parent body chemistry and compounds of potential importance for the origin of life. Among the classes of organic compounds found in Murchison are amino acids, amides, carboxylic acids, hydroxy acids, sulfonic acids, phosphonic acids, purines and pyrimidines (Table 1). Compounds such as these were quite likely delivered to the early Earth in asteroids and comets. Until now, polyhydroxylated compounds (polyols), including sugars (polyhydroxy aldehydes or ketones), sugar alcohols, sugar acids, etc., had not been identified in Murchison. Ribose and deoxyribose, five-carbon sugars, are central to the role of contemporary nucleic acids, DNA and RNA. Glycerol, a three-carbon sugar alcohol, is a constituent of all known biological membranes. Due to the relative lability of sugars, some researchers have questioned the lifetime of sugars under the presumed conditions on the early Earth and postulated other (more stable) compounds as constituents of the first replicating molecules. The identification of potential sources and/or formation mechanisms of pre-biotic polyols would add to the understanding of what organic compounds were available, and for what length of time, on the ancient Earth.

  12. [Energies of organic compounds

    SciTech Connect

    1995-07-01

    The first part of our study of the enthalpy of reduction of carbonyl compounds has been completed and includes four aldehydes, acetone, a series of cyclic ketones and ethyl acetate. Results suggest that some of the literature data for these compounds are significantly in error. Equilibrium constants have been measured for the reaction of carbonyl compounds with water to give hydrates as well as with methanol to give either hemiacetals or acetals. They cover a wide range, and studies are underway to determine the reasons for the differences. Studies of the enthalpies of hydration of some alkenes which yield tertiary alcohols have been completed, as well as a study of the hydrolysis of lactones. The ``gauche effect`` has been studied, and has been shown to result from the formation of bent bonds when atoms of much different electronegativity are joined.

  13. PERSISTENT PERFLUORINATED ORGANIC COMPOUNDS

    EPA Science Inventory

    Perfluorinated compounds (PFCs) have gained notoriety in the recent past. Global distribution of PFCs in wildlife, environmental samples and humans has sparked a recent increase in new investigations concerning PFCs. Historically PFCs have been used in a wide variety of consume...

  14. Energies of organic compounds

    SciTech Connect

    Wiberg, K.B.

    1995-07-01

    The studies included hydrolysis of ketals, hydration of alkenes, barrier to rotation about C-O bonds in esters and acids, hydrolysis of lactones, reduction of ketones, non-bonded interactions, and enthalpies of vaporization of ketones, ketals, and other compounds.

  15. Organic Compounds in Stardust

    NASA Technical Reports Server (NTRS)

    McKay, David S.; Clemett. Simon J.; Sandford, Scott A.; Nakamura-Messenger, Keiko; Hoerz, Fredrich

    2011-01-01

    The successful return of the STARDUST spacecraft provides a unique opportunity to investigate the nature and distribution of organic matter in cometary dust particles collected from Comet 81P/Wild-2. Analysis of individual cometary impact tracks in silica aerogel using the technique of two-step laser mass spectrometry (L2MS) demonstrates the presence of complex aromatic organic matter. While concerns remain as to the organic purity of the aerogel collection medium and the thermal effects associated with hypervelocity capture, the majority of the observed organic species appear indigenous to the impacting particles and are hence of cometary origin. While the aromatic fraction of the total organic matter present is believed to be small, it is notable in that it appears to be N-rich. Spectral analysis in combination with instrumental detection sensitivities suggest that N is incorporated predominantly in the form of aromatic nitriles (R-C N). While organic species in the STARDUST samples do share some similarities with those present in the matrices of carbonaceous chondrites, the closest match is found with stratospherically collected interplanetary dust particles. These findings are consistent with the notion that a fraction of interplanetary dust is of cometary origin. The presence of complex organic N-containing species in comets has astrobiological implications since comets are likely to have contributed to the prebiotic chemical inventory of both the Earth and Mars.

  16. Photochemical dimerization of organic compounds

    DOEpatents

    Crabtree, Robert H.; Brown, Stephen H.; Muedas, Cesar A.; Ferguson, Richard R.

    1992-01-01

    At least one of selectivity and reaction rate of photosensitized vapor phase dimerizations, including dehydrodimerizations, hydrodimerizations and cross-dimerizations of saturated and unsaturated organic compounds is improved by conducting the dimerization in the presence of hydrogen or nitrous oxide.

  17. [Energies of organic compounds

    SciTech Connect

    Wiberg, K.B.

    1991-12-31

    The enthalpy of reduction of lactones to the corresponding diols has been determined, allowing the enthaipies of formation of the lactones to be determined. Results of this study agree well with data obtained for enthalpies of hydrolysis of the lactones. We have begun the measurement of the enthalpies of reduction of norbornanones, and we have shown that it is possible to determine the difference in energy between the exo and endo forms of the product alcohols by measuring the equilibrium constant as a function of temperature. The study of the enthalpies of hydration of carbonyl compounds has continued, and the enthalpies of hydrolysis of the corresponding ketals is being determined. The study of the enthalpies of hydration of alkenes is nearly completed, and the rearrangement reactions which were uncovered are being investigated.

  18. Extraterrestrial Organic Compounds in Meteorites

    NASA Technical Reports Server (NTRS)

    Botta, Oliver; Bada, Jeffrey L.; Meyer, Michael (Technical Monitor)

    2003-01-01

    Many organic compounds or their precursors found in meteorites originated in the interstellar or circumstellar medium and were later incorporated into planetesimals during the formation of the solar system. There they either survived intact or underwent further processing to synthesize secondary products on the meteorite parent body. The most distinct feature of CI and CM carbonaceous chondrites, two types of stony meteorites, is their high carbon content (up to 3% of weight), either in the form of carbonates or of organic compounds. The bulk of the organic carbon consists of an insoluble macromolecular material with a complex structure. Also present is a soluble organic fraction, which has been analyzed by several separation and analytical procedures. Low detection limits can be achieved by derivatization of the organic molecules with reagents that allow for analysis by gas chromatography/mass spectroscopy and high performance liquid chromatography. The CM meteorite Murchison has been found to contain more than 70 extraterrestrial amino acids and several other classes of compounds including carboxylic acids, hydroxy carboxylic acids, sulphonic and phosphonic acids, aliphatic, aromatic and polar hydrocarbons, fullerenes, heterocycles as well as carbonyl compounds, alcohols, amines and amides. The organic matter was found to be enriched in deuterium, and distinct organic compounds show isotopic enrichments of carbon and nitrogen relative to terrestrial matter.

  19. Extraterrestrial Organic Compounds in Meteorites

    NASA Technical Reports Server (NTRS)

    Botta, Oliver; Bada, Jeffrey L.; Meyer, Michael (Technical Monitor)

    2003-01-01

    Many organic compounds or their precursors found in meteorites originated in the interstellar or circumstellar medium and were later incorporated into planetesimals during the formation of the solar system. There they either survived intact or underwent further processing to synthesize secondary products on the meteorite parent body. The most distinct feature of CI and CM carbonaceous chondrites, two types of stony meteorites, is their high carbon content (up to 3% of weight), either in the form of carbonates or of organic compounds. The bulk of the organic carbon consists of an insoluble macromolecular material with a complex structure. Also present is a soluble organic fraction, which has been analyzed by several separation and analytical procedures. Low detection limits can be achieved by derivatization of the organic molecules with reagents that allow for analysis by gas chromatography/mass spectroscopy and high performance liquid chromatography. The CM meteorite Murchison has been found to contain more than 70 extraterrestrial amino acids and several other classes of compounds including carboxylic acids, hydroxy carboxylic acids, sulphonic and phosphonic acids, aliphatic, aromatic and polar hydrocarbons, fullerenes, heterocycles as well as carbonyl compounds, alcohols, amines and amides. The organic matter was found to be enriched in deuterium, and distinct organic compounds show isotopic enrichments of carbon and nitrogen relative to terrestrial matter.

  20. Biomedical Compounds from Marine organisms

    PubMed Central

    Jha, Rajeev Kumar; Zi-rong, Xu

    2004-01-01

    The Ocean, which is called the ‘mother of origin of life’, is also the source of structurally unique natural products that are mainly accumulated in living organisms. Several of these compounds show pharmacological activities and are helpful for the invention and discovery of bioactive compounds, primarily for deadly diseases like cancer, acquired immuno-deficiency syndrome (AIDS), arthritis, etc., while other compounds have been developed as analgesics or to treat inflammation, etc. The life-saving drugs are mainly found abundantly in microorganisms, algae and invertebrates, while they are scarce in vertebrates. Modern technologies have opened vast areas of research for the extraction of biomedical compounds from oceans and seas.

  1. Photoprotective compounds from marine organisms.

    PubMed

    Rastogi, Rajesh P; Richa; Sinha, Rajeshwar P; Singh, Shailendra P; Häder, Donat-P

    2010-06-01

    The substantial loss in the stratospheric ozone layer and consequent increase in solar ultraviolet radiation on the earth's surface have augmented the interest in searching for natural photoprotective compounds in organisms of marine as well as freshwater ecosystems. A number of photoprotective compounds such as mycosporine-like amino acids (MAAs), scytonemin, carotenoids and several other UV-absorbing substances of unknown chemical structure have been identified from different organisms. MAAs form the most common class of UV-absorbing compounds known to occur widely in various marine organisms; however, several compounds having UV-screening properties still need to be identified. The synthesis of scytonemin, a predominant UV-A-photoprotective pigment, is exclusively reported in cyanobacteria. Carotenoids are important components of the photosynthetic apparatus that serve both light-harvesting and photoprotective functions, either by direct quenching of the singlet oxygen or other toxic reactive oxygen species or by dissipating the excess energy in the photosynthetic apparatus. The production of photoprotective compounds is affected by several environmental factors such as different wavelengths of UVR, desiccation, nutrients, salt concentration, light as well as dark period, and still there is controversy about the biosynthesis of various photoprotective compounds. Recent studies have focused on marine organisms as a source of natural bioactive molecules having a photoprotective role, their biosynthesis and commercial application. However, there is a need for extensive work to explore the photoprotective role of various UV-absorbing compounds from marine habitats so that a range of biotechnological and pharmaceutical applications can be found.

  2. Organophosphorus Compounds in Organic Electronics.

    PubMed

    Shameem, Muhammad Anwar; Orthaber, Andreas

    2016-07-25

    This Minireview describes recent advances of organophosphorus compounds as opto-electronic materials in the field of organic electronics. The progress of (hetero-) phospholes, unsaturated phosphanes, and trivalent and pentavalent phosphanes since 2010 is covered. The described applications of organophosphorus materials range from single molecule sensors, field effect transistors, organic light emitting diodes, to polymeric materials for organic photovoltaic applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. A Pilot Study of the Effectiveness of Indoor Plants for Removal of Volatile Organic Compounds in Indoor Air in a Seven-Story Office Building

    SciTech Connect

    Apte, Michael G.; Apte, Joshua S.

    2010-04-27

    plants used in the rooftop greenhouse and on the floors were made up of a number of species selected for the following functions: daytime metabolic carbon dioxide (CO{sub 2}) absorption, nighttime metabolic CO{sub 2} absorption, and volatile organic compound (VOC) and inorganic gas absorption/removal for air cleaning. The building contains a reported 910 indoor plants. Daytime metabolic species reported by the PBC include Areca Palm, Oxycardium, Rubber Plant, and Ficus alii totaling 188 plants (21%). The single nighttime metabolic species is the Sansevieria with a total of 28 plants (3%). The 'air cleaning' plant species reported by the PBC include the Money Plant, Aglaonema, Dracaena Warneckii, Bamboo Palm, and Raphis Palm with a total of 694 plants (76%). The plants in the greenhouse (Areca Palm, Rubber Plant, Ficus alii, Bamboo Palm, and Raphis Palm) numbering 161 (18%) of those in the building are grown hydroponically, with the room air blown by fan across the plant root zones. The plants on the building floors are grown in pots and are located on floors 1-6. We conducted a one-day monitoring session in the PBC on January 1, 2010. The date of the study was based on availability of the measurement equipment that the researchers had shipped from Lawrence Berkeley National Lab in the U.S.A. The study date was not optimal because a large proportion of the regular building occupants were not present being New Year's Day. An estimated 40 people were present in the building all day during January 1. This being said, the building systems were in normal operations, including the air handlers and other HVAC components. The study was focused primarily on measurements in the Greenhouse and 3rd and 5th floor environments as well as rooftop outdoors. Measurements included a set of volatile organic compounds (VOCs) and aldehydes, with a more limited set of observations of indoor and outdoor particulate and carbon dioxide concentrations. Continuous measurements of Temperature (T

  4. Evaluation of the treatment performance of lab-scaled vertical flow constructed wetlands in removal of organic compounds, color and nutrients in azo dye-containing wastewater.

    PubMed

    Dogdu, Gamze; Yalcuk, Arda

    2016-01-01

    The objective of this study is to examine the treatment performance of vertical flow intermittent feeding constructed wetland (VFCW) in removal of organic pollution, nutrients and color in azo-dye containing wastewater. The systems consisted of PVC reactors, some filling materials such as gravel, sand and zeolite and wetland plants including Typha angustifolia and Canna indica. The average treatment efficiency of the systems for COD, color, sulphate, NH4-N, and PO4-P were in the range of 57-63%, 94-99%, 44-48%, 39-44%, and 84-88%, respectively among the VFCW reactors. It is concluded that VFCW reactor system can effectively be used in the treatment of dye-rich wastewater, especially for the removal of color and in the reduction of COD. Biofilm formation and cleavage of azo bonds could be observed by SEM and FTIR results, respectively. Almost similar NH4-N and PO4-P removal were obtained in all reactors by using same amount of zeolite media.

  5. Apparatus Removes Organic Contaminants From Water

    NASA Technical Reports Server (NTRS)

    Akse, James R.; Thompson, John

    1994-01-01

    Catalytic-oxidation apparatus removes low-molecular-weight, polar, nonionizable organic contaminants from wastewater. Wastewater stream, previously treated by multifiltration process, pumped through apparatus for removal of trace organic contaminants. After injection of oxygen, flow preheated and enters catalytic reactor, where organic contaminants broken down into carbon dioxide and water. Carbon dioxide and unused oxygen removed in degasser.

  6. Students' Categorizations of Organic Compounds

    ERIC Educational Resources Information Center

    Domin, Daniel S.; Al-Masum, Mohammad; Mensah, John

    2008-01-01

    Categorization is a fundamental psychological ability necessary for problem solving and many other higher-level cognitive tasks. In organic chemistry, students must establish groupings of different chemical compounds in order not only to solve problems, but also to understand course content. Classic models of categorization emphasize similarity as…

  7. Construction and economics of a pilot/full-scale biological trickling filter reactor for the removal of volatile organic compounds from polluted air.

    PubMed

    Deshusses, M A; Webster, T S

    2000-11-01

    The design and the construction of an actual 8.7-m3 pilot/full-scale biotrickling filter for waste air treatment is described and compared with a previous conceptual scale-up of a laboratory reactor. The reactor construction costs are detailed and show that about one-half of the total reactor costs ($97,000 out of $178,000) was for personnel and engineering time, whereas approximately 20% was for monitoring and control equipment. A detailed treatment cost analysis demonstrated that, for an empty bed contact time of 90 sec, the overall treatment costs (including capital charges) were as low as $8.7/1000 m3air in the case where a nonchlorinated volatile organic compound (VOC) was treated, and $14/1000 m3air for chlorinated compounds such as CH2Cl2. Comparison of these costs with conventional air pollution control techniques demonstrates excellent perspectives for more field applications of biotrickling filters. As the specific costs of building and operating biotrickling filter reactors decrease with increasing size of the reactor, the cost benefit of biotrickling filtration is expected to increase for full technical-scale bioreactors.

  8. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

    1993-01-05

    Aromatic compounds are alkylated in a combination reactor/distillation column comprising a vessel suitable for operating between 70 C and 500 C and from 0.5 to 20 atmospheres pressure; an inert distillation packing in the lower one-third of said vessel; solid acidic catalytic material such as zeolites or an acidic cation exchange resin supported in the middle one-third of said vessel; and inert distillation packing in the upper one-third of said vessel. A benzene inlet is located near the upper end of the vessel; an olefin inlet is juxtaposed with said solid acidic catalytic material; a bottoms outlet is positioned near the bottom of said vessel for removing said cumene and ethyl benzene; and an overhead outlet is placed at the top of said vessel for removing any unreacted benzene and olefin.

  9. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, Jr., Lawrence A.; Arganbright, Robert P.; Hearn, Dennis

    1993-01-01

    Aromatic compounds are alkylated in a combination reactor/distillation column comprising a vessel suitable for operating between 70.degree. C. and 500.degree. C. and from 0.5 to 20 atmospheres pressure; an inert distillation packing in the lower one-third of said vessel; solid acidic catalytic material such as zeolites or an acidic cation exchange resin supported in the middle one-third of said vessel; and inert distillation packing in the upper one-third of said vessel. A benzene inlet is located near the upper end of the vessel; an olefin inlet is juxtaposed with said solid acidic catalytic material; a bottoms outlet is positioned near the bottom of said vessel for removing said cumene and ethyl benzene; and an overhead outlet is placed at the top of said vessel for removing any unreacted benzene and olefin.

  10. Combined chemical and microbiological removal of organic sulfur from coal

    SciTech Connect

    Raphaelian, L.A.

    1991-01-01

    The objective of this work is to investigate techniques for chemically converting the sulfur containing organic compounds in coal to compounds that can be treated microbiologically to remove the organically bound sulfur. The goal is to achieve an economically feasible mild chemical oxidation of the organic sulfur in a representative Illinois Basin coal by converting the sulfur to sulfoxides and sulfones; the carbon sulfur bond in the sulfoxides and sulfones would then be broken microbiologically and the sulfur removed from the coal as sulfate.

  11. Effectiveness of decanter modifications on organic removal

    SciTech Connect

    Lambert, D.P.

    1992-08-20

    A series of runs were planned in the Precipitate Hydrolysis Experimental Facility (PHEF) at the Savannah River Plant to determine the effectiveness of equipment and process modifications on the PHEF decanter organic removal efficiency. Runs 54-59 were planned to test the effectiveness of spray recirculation, a new decanter, heated organic recirculation and aqueous drawoff on organic removal efficiency in the revised HAN flowsheet. Runs 60-63 were planned to provide a comparison of the original and new decanter designs on organic removal efficiency in the late wash flowsheet without organic recirculation. Operational problems were experienced in both the PHEF and IDMS pilot facilities because of the production of high boiling organics and the low organic removal efficiency of the PHEF decanters. To prevent these problems in the DWPF Salt and Chemical Cells, modifications were proposed to the decanter and flowsheet to maximize the organic removal efficiency and minimize production of high boiling organics.

  12. Nonoxidative removal of organics in the activated sludge process

    PubMed Central

    Modin, Oskar; Persson, Frank; Wilén, Britt-Marie; Hermansson, Malte

    2016-01-01

    ABSTRACT The activated sludge process is commonly used to treat wastewater by aerobic oxidation of organic pollutants into carbon dioxide and water. However, several nonoxidative mechanisms can also contribute to removal of organics. Sorption onto activated sludge can remove a large fraction of the colloidal and particulate wastewater organics. Intracellular storage of, e.g., polyhydroxyalkanoates (PHA), triacylglycerides (TAG), or wax esters can convert wastewater organics into precursors for high-value products. Recently, several environmental, economic, and technological drivers have stimulated research on nonoxidative removal of organics for wastewater treatment. In this paper, we review these nonoxidative removal mechanisms as well as the existing and emerging process configurations that make use of them for wastewater treatment. Better utilization of nonoxidative processes in activated sludge could reduce the wasteful aerobic oxidation of organic compounds and lead to more resource-efficient wastewater treatment plants. PMID:27453679

  13. Molybdenum compounds in organic synthesis

    NASA Astrophysics Data System (ADS)

    Khusnutdinov, R. I.; Oshnyakova, T. M.; Dzhemilev, U. M.

    2017-02-01

    The review presents the first analysis and systematic discussion of data published in the last 35–40 years on the use of molybdenum compounds and complexes in organic synthesis and catalysis of various ion coordination and radical reactions. Detailed account is given of the key trends in the use of molybdenum complexes as catalysts of alkene epoxidation and oxyketonation, oxidation of sulfur, nitrogen and phosphorus compounds, hydrosilylation of 1,3-dienes, ketones and aldehydes, hydrostannylation of acetylenes and hydrogermylation of norbornadienes. Considerable attention is paid to the description of new reactions and in situ generation of highly reactive hypohalites, ROX and HOX, induced by molybdenum complexes and the use of hypohalites in oxidative transformations. Data on the application of molybdenum complexes in well-known reactions are discussed, including Kharasch and Pauson–Khand reactions, allylic alkylation of C-nucleophiles, aminocarbonylation of halo derivatives and oligomerization of cyclic dienes, trienes, alkynes and 1,3-dienes. The last Section of the review considers 'unusual' organic reactions involving molybdenum compounds and complexes. The bibliography includes 257 references.

  14. Removal of trace organic micropollutants by drinking water biological filters.

    PubMed

    Zearley, Thomas L; Summers, R Scott

    2012-09-04

    The long-term removal of 34 trace organic micropollutants (<1 μg L(-1)) was evaluated and modeled in drinking water biological filters with sand media from a full-scale plant. The micropollutants included pesticides, pharmaceuticals, and personal care products, some of which are endocrine disrupting chemicals, and represent a wide range of uses, chemical structures, adsorbabilities, and biodegradabilities. Micropollutant removal ranged from no measurable removal (<15%) for 13 compounds to removal below the detection limit and followed one of four trends over the one year study period: steady state removal throughout, increasing removal to steady state (acclimation), decreasing removal, or no removal (recalcitrant). Removals for all 19 nonrecalcitrant compounds followed first-order kinetics when at steady state with increased removal at longer empty bed contact times (EBCT). Rate constants were calculated, 0.02-0.37 min(-1), and used in a pseudo-first-order rate model with the EBCT to predict removals in laboratory biofilters at a different EBCT and influent conditions. Drinking water biofiltration has the potential to be an effective process for the control of many trace organic contaminants and a pseudo-first-order model can serve as an appropriate method for approximating performance.

  15. Mass of chlorinated volatile organic compounds removed by Pump-and-Treat, Naval Air Warfare Center, West Trenton, New Jersey, 1996-2010

    USGS Publications Warehouse

    Lacombe, Pierre J.

    2011-01-01

    Pump and Treat (P&T) remediation is the primary technique used to contain and remove trichloroethylene (TCE) and its degradation products cis 1-2,dichloroethylene (cDCE) and vinyl chloride (VC) from groundwater at the Naval Air Warfare Center (NAWC), West Trenton, NJ. Three methods were used to determine the masses of TCE, cDCE, and VC removed from groundwater by the P&T system since it became fully operational in 1996. Method 1, is based on the flow volume and concentrations of TCE, cDCE, and VC in groundwater that entered the P&T building as influent. Method 2 is based on withdrawal volume from each active recovery well and the concentrations of TCE, cDCE, and VC in the water samples from each well. Method 3 compares the maximum monthly amount of TCE, cDCE, and VC from Method 1 and Method 2. The greater of the two values is selected to represent the masses of TCE, cDCE and VC removed from groundwater each month. Previously published P&T monthly reports used Method 1 to determine the mass of TCE, cDCE, and VC removed. The reports state that 8,666 pounds (lbs) of TCE, 13,689 lbs of cDCE, and 2,455 lbs of VC were removed by the P&T system during 1996-2010. By using Method 2, the mass removed was determined to be 8,985 lbs of TCE, 17,801 lbs of cDCE, and 3,056 lbs of VC removed, and Method 3, resulted in 10,602 lbs of TCE, 21,029 lbs of cDCE, and 3,496 lbs of VC removed. To determine the mass of original TCE removed from groundwater, the individual masses of TCE, cDCE, and VC (determined using Methods 1, 2, and 3) were converted to numbers of moles, summed, and converted to pounds of original TCE. By using the molar conversion the mass of original TCE removed from groundwater by Methods 1, 2, and 3 was 32,381 lbs, 39,535 lbs, and 46,452 lbs, respectively, during 1996-2010. P&T monthly reports state that 24,805 lbs of summed TCE, cDCE, and VC were removed from groundwater. The simple summing method underestimates the mass of original TCE removed by the P&T system.

  16. Volatile organic compound sensor system

    DOEpatents

    Schabron, John F [Laramie, WY; Rovani, Jr., Joseph F.; Bomstad, Theresa M [Waxahachie, TX; Sorini-Wong, Susan S [Laramie, WY; Wong, Gregory K [Laramie, WY

    2011-03-01

    Generally, this invention relates to the development of field monitoring methodology for new substances and sensing chemical warfare agents (CWAs) and terrorist substances. It also relates to a portable test kit which may be utilized to measure concentrations of halogenated volatile organic compounds (VOCs) in the field. Specifically it relates to systems for reliably field sensing the potential presence of such items while also distinguishing them from other elements potentially present. It also relates to overall systems and processes for sensing, reacting, and responding to an indicated presence of such substance, including modifications of existing halogenated sensors and arrayed sensing systems and methods.

  17. Volatile organic compound sensor system

    DOEpatents

    Schabron, John F [Laramie, WY; Rovani, Jr., Joseph F.; Bomstad, Theresa M [Laramie, WY; Sorini-Wong, Susan S [Laramie, WY

    2009-02-10

    Generally, this invention relates to the development of field monitoring methodology for new substances and sensing chemical warfare agents (CWAs) and terrorist substances. It also relates to a portable test kit which may be utilized to measure concentrations of halogenated volatile organic compounds (VOCs) in the field. Specifically it relates to systems for reliably field sensing the potential presence of such items while also distinguishing them from other elements potentially present. It also relates to overall systems and processes for sensing, reacting, and responding to an indicated presence of such substance, including modifications of existing halogenated sensors and arrayed sensing systems and methods.

  18. Organic compounds in carbonaceous meteorites.

    PubMed

    Sephton, Mark A

    2002-06-01

    The carbonaceous chondrite meteorites are fragments of asteroids that have remained relatively unprocessed since the formation of the solar system 4.6 billion years ago. These carbon-rich objects contain a variety of extraterrestrial organic molecules that constitute a record of chemical evolution prior to the origin of life. Compound classes include aliphatic hydrocarbons, aromatic hydrocarbons, amino acids, carboxylic acids, sulfonic acids, phosphonic acids, alcohols, aldehydes, ketones, sugars, amines, amides, nitrogen heterocycles, sulfur heterocycles and a relatively abundant high molecular weight macromolecular material. Structural and stable isotopic characteristics suggest that a number of environments may have contributed to the organic inventory, including interstellar space, the solar nebula and the asteroidal meteorite parent body. This review covers work published between 1950 and the present day and cites 193 references.

  19. DEMONSTRATION OF PILOT-SCALE PREVAPORATION SYSTEMS FOR VOLATILE ORGANIC COMPOUND REMOVAL FROM A SURFACTANT ENHANCED AQUIFER REMEDIATION FLUID. I. SPIRAL WOUND MEMBRANE MODULES

    EPA Science Inventory

    During the summer of 1996, a pilot-scale demonstration of a surfactant enhanced aquifer remediation (SEAR) process for removal of dense non-aqueous phase liquids (DNAPLs) from soils was conducted at Hill Air Force Base in Layton, Utah. Five thousand gallons of the extracted DNAP...

  20. DEMONSTRATION OF PILOT-SCALE PREVAPORATION SYSTEMS FOR VOLATILE ORGANIC COMPOUND REMOVAL FROM A SURFACTANT ENHANCED AQUIFER REMEDIATION FLUID. I. SPIRAL WOUND MEMBRANE MODULES

    EPA Science Inventory

    During the summer of 1996, a pilot-scale demonstration of a surfactant enhanced aquifer remediation (SEAR) process for removal of dense non-aqueous phase liquids (DNAPLs) from soils was conducted at Hill Air Force Base in Layton, Utah. Five thousand gallons of the extracted DNAP...

  1. Removal of endocrine disrupting compounds during conventional wastewater treatment.

    PubMed

    Kanda, R; Churchley, J

    2008-03-01

    There is evidence that aquatic organisms downstream of some sewage treatment works show endocrine disruption as a result of exposure to substances in the effluent. As a result, the Environment Agency of England and Wales, in collaboration with the UK Government and the water industry, has started an intensive programme to determine the fate and behaviour of endocrine disrupting compounds in sewage treatment works. Sampling sites for the endocrine disruption demonstration programme are located throughout England and Wales. This paper presents data from Nuneaton sewage treatment works (Warwickshire, England), a modem nitrifying activated sludge plant serving an equivalent population of 98,000 and one of the selected sites for the demonstration programme. Results for the 24-hour survey carried out in June 2006 in which manual grab samples were taken hourly show excellent removal of estrone, estradiol, nonyl-phenol and the nonylphenolethoxylates (3-5 EO units) at 97, 99, 94 and 98% respectively. They also show excellent removal (99%) of estrogenicity, measured by the YES bioassay. However the removal of ethynylestradiol was poor at only 3%. In November 2006, a further survey was carried out comprising grab samples taken at 4-hourly intervals across a continuous 7-day period. This monitoring confirmed the good removal of estrone and estradiol, at 97.8% and 96.3% respectively as well as an excellent reduction in estrogenicity (98.3%), but again showed poor removal of ethynylestradiol of 5.6%. There was evidence of a diurnal pattern for estrone and estradiol concentrations and to a lesser extent for ethynylestradiol in samples of crude sewage with works returns. Peak concentrations tended to occur at around midday.

  2. Mercury Removal from Waste Organics

    SciTech Connect

    Cummins, R.L.; Klasson, T.; Taylor, P.A.

    1999-02-28

    Mercury was effectively removed from the oil via sorption using SAMMS.The method was demonstrated on a large scale using ORNL waste oil contaminated with mercury. This technology is ready for further demonstration and implementation when the SAMMS material is available in large quantities.

  3. Volatile organic compound sensing devices

    DOEpatents

    Lancaster, G.D.; Moore, G.A.; Stone, M.L.; Reagen, W.K.

    1995-08-29

    Apparatus employing vapochromic materials in the form of inorganic double complex salts which change color reversibly when exposed to volatile organic compound (VOC) vapors is adapted for VOC vapor detection, VOC aqueous matrix detection, and selective VOC vapor detection. The basic VOC vapochromic sensor is incorporated in various devices such as a ground probe sensor, a wristband sensor, a periodic sampling monitor, a soil/water penetrometer, an evaporative purge sensor, and various vacuum-based sensors which are particularly adapted for reversible/reusable detection, remote detection, continuous monitoring, or rapid screening of environmental remediation and waste management sites. The vapochromic sensor is used in combination with various fiber optic arrangements to provide a calibrated qualitative and/or quantitative indication of the presence of VOCs. 15 figs.

  4. Volatile organic compound sensing devices

    DOEpatents

    Lancaster, Gregory D.; Moore, Glenn A.; Stone, Mark L.; Reagen, William K.

    1995-01-01

    Apparatus employing vapochromic materials in the form of inorganic double complex salts which change color reversibly when exposed to volatile organic compound (VOC) vapors is adapted for VOC vapor detection, VOC aqueous matrix detection, and selective VOC vapor detection. The basic VOC vapochromic sensor is incorporated in various devices such as a ground probe sensor, a wristband sensor, a periodic sampling monitor, a soil/water penetrometer, an evaporative purge sensor, and various vacuum-based sensors which are particularly adapted for reversible/reusable detection, remote detection, continuous monitoring, or rapid screening of environmental remediation and waste management sites. The vapochromic sensor is used in combination with various fiber optic arrangements to provide a calibrated qualitative and/or quantitative indication of the presence of VOCs.

  5. Removal of aromatic hydrocarbon compounds by hydroxypropyl-cyclodextrin

    SciTech Connect

    1999-09-15

    Activated carbon has been used for the recovery and removal of benzene, toluene, and xylenes in air and water for a long time. However, removal of benzene, toluene, and xylenes from soil is very difficult. They can be removed by an increase in the apparent solubility of organic compounds in soil. The apparent solubilities of benzene, toluene, and xylene were investigated to estimate their inclusion behavior into natural cyclodextrins (CDs) and hydroxypropyl-cyclodextrins (HP-CDs) in the liquid phase. The apparent solubilities of benzene, toluene, and xylenes did not increase by adding natural CDs but did increase when HP-CDs were added. Benzene, toluene, and xylenes in a HP-CD solution depended on the relationship between the molecular diameter of benzene, toluene, and xylenes, the CD cavity size, and the 1-octanol-water partition coefficient. That of p-xylene was larger than that of o-xylene and m-xylene because of the smallest steric hindrance of p-xylene.

  6. Treatment System for Removing Halogenated Compounds from Contaminated Sources

    NASA Technical Reports Server (NTRS)

    Quinn, Jacqueline W. (Inventor); Clausen, Christian A. (Inventor); Yestrebsky, Cherie L. (Inventor)

    2015-01-01

    A treatment system and a method for removal of at least one halogenated compound, such as PCBs, found in contaminated systems are provided. The treatment system includes a polymer blanket for receiving at least one non-polar solvent. The halogenated compound permeates into or through a wall of the polymer blanket where it is solubilized with at least one non-polar solvent received by said polymer blanket forming a halogenated solvent mixture. This treatment system and method provides for the in situ removal of halogenated compounds from the contaminated system. In one embodiment, the halogenated solvent mixture is subjected to subsequent processes which destroy and/or degrade the halogenated compound.

  7. Semivolatile organic compounds in indoor environments

    NASA Astrophysics Data System (ADS)

    Weschler, Charles J.; Nazaroff, William W.

    Semivolatile organic compounds (SVOCs) are ubiquitous in indoor environments, redistributing from their original sources to all indoor surfaces. Exposures resulting from their indoor presence contribute to detectable body burdens of diverse SVOCs, including pesticides, plasticizers, and flame retardants. This paper critically examines equilibrium partitioning of SVOCs among indoor compartments. It proceeds to evaluate kinetic constraints on sorptive partitioning to organic matter on fixed surfaces and airborne particles. Analyses indicate that equilibrium partitioning is achieved faster for particles than for typical indoor surfaces; indeed, for a strongly sorbing SVOC and a thick sorptive reservoir, equilibrium partitioning is never achieved. Mass-balance considerations are used to develop physical-science-based models that connect source- and sink-rates to airborne concentrations for commonly encountered situations, such as the application of a pesticide or the emission of a plasticizer or flame retardant from its host material. Calculations suggest that many SVOCs have long indoor persistence, even after the primary source is removed. If the only removal mechanism is ventilation, moderately sorbing compounds ( Koa > 10 10) may persist indoors for hundreds to thousands of hours, while strongly sorbing compounds ( Koa > 10 12) may persist for years. The paper concludes by applying the newly developed framework to explore exposure pathways of building occupants to indoor SVOCs. Accumulation of SVOCs as a consequence of direct air-to-human transport is shown to be potentially large, with a maximum indoor-air processing rate of 10-20 m 3/h for SVOC uptake by human skin, hair and clothing. Levels on human skin calculated with a simple model of direct air-to-skin transfer agree remarkably well with levels measured in dermal hand wipes for SVOCs possessing a wide range of octanol-air partition coefficients.

  8. Removal of arsenic compounds from petroliferous liquids

    DOEpatents

    Fish, Richard H.

    1985-01-01

    Described is a process for removing arsenic from petroliferous derived liquids by contacting said liquid at an elevated temperature with a divinylbenzene-crosslinked polystyrene having catechol ligands anchored thereon. Also, described is a process for regenerating spent catecholated polystyrene by removal of the arsenic bound to it from contacting petroliferous liquid as described above and involves: a. treating said spent catecholated polystyrene, at a temperature in the range of about 20.degree. to 100.degree. C. with an aqueous solution of at least one carbonate and/or bicarbonate of ammonium, alkali and alkaline earth metals, said solution having a pH between about 8 and 10 and, b. separating the solids and liquids from each other. Preferably the regeneration treatment is in two steps wherein step (a) is carried out with an aqueous alcoholic carbonate solution containing lower alkyl alcohol, and, steps (a) and (b) are repeated using a bicarbonate.

  9. High performance liquid chromatography, thin layer chromatography and spectrophotometric studies on the removal of biogenic amines from some Egyptian foods using organic, inorganic and natural compounds.

    PubMed

    Mohamed, Gehad G; El-Hameed, Azza K Abd; El-Din, A M M Nezam; El-Din, Lara A M M N

    2010-04-01

    This work has been carried out to investigate the conditions which lead to removal of the biogenic amines through the model system. Also, the main goal of this research work is trying to remove biogenic amines; histamine and tyramine, from some Egyptian foods such as tomato, strawberry, banana and mango to prevent their allergy effect. Histamine and tyramine have been affected by pyrogallol, catechol, starch, ascorbic and chlorogenic acids at different levels with different conditions. Some natural additives like glucose, spices, milk, vanillin, starch, orange juice, ascorbic and citric acids, showed an effective effect on disappearance of histamine and tyramine. By studying the effect of some additives on biogenic amines, it was found that tomato showed a decrease in histamine and tyramine concentrations by adding spices. Strawberry and banana showed a clear decrease in histamine and tyramine concentrations by treating them with ascorbic acid. Treating mango by milk led to increase of histamine level while milk with chocolate increases both histamine and tyramine concentrations.

  10. Removal of arsenic compounds from petroliferous liquids

    DOEpatents

    Fish, R.H.

    1984-04-06

    The present invention in one aspect comprises a process for removing arsenic from petroliferous-derived liquids by contacting said liquid with a divinylbenzene-crosslinked polystyrene polymer (i.e. PS-DVB) having catechol ligands anchored to said polymer, said contacting being at an elevated temperature. In another aspect, the invention is a process for regenerating spent catecholated polystyrene polymer by removal of the arsenic bound to it from contacting petroliferous liquid in accordance with the aspect described above which regenerating process comprises: (a) treating said spent catecholated polystyrene polymer with an aqueous solution of at least one member selected from the group consisting of carbonates and bicarbonates of ammonium, alkali metals, and alkaline earth metals, said solution having a pH between about 8 and 10, and said treating being at a temperature in the range of about 20/sup 0/ to 100/sup 0/C; (b) separating the solids and liquids from each other. In a preferred embodiment the regeneration treatment is in two steps wherein step: (a) is carried out with an aqueous alcoholic carbonate solution which includes at least one lower alkyl alcohol, and, steps (c) and (d) are added. Steps (c) and (d) comprise: (c) treating the solids with an aqueous alcoholic solution of at least one ammonium, alkali or alkaline earth metal bicarbonate at a temperature in the range of about 20 to 100/sup 0/C; and (d) separating the solids from the liquids.

  11. High-temperature removal of cadmium compounds using solid sorbents

    SciTech Connect

    Uberol, M.; Shadman, F. )

    1991-07-01

    Emission of cadmium compounds is a major problem in many coal combustors and waste incinerators. In the present work, the use of solid sorbents for removal of cadmium compounds from high-temperature flue gases is investigated. The sorbents tested were silica, alumina, kaolinite, emathlite, and lime. Compounds containing aluminum oxide show high cadmium removal efficiency. In particular, bauxite has the highest rate and capacity for cadmium capture. The overall sorption process is not just physical adsorption, but rather a complex combination of adsorption and chemical reaction.

  12. Removal of organic contaminants by RO and NF membranes

    NASA Technical Reports Server (NTRS)

    Yoon, Yeomin; Lueptow, Richard M.

    2005-01-01

    Rejection characteristics of organic and inorganic compounds were examined for six reverse osmosis (RO) membranes and two nanofiltration (NF) membranes that are commercially available. A batch stirred-cell was employed to determine the membrane flux and the solute rejection for solutions at various concentrations and different pH conditions. The results show that for ionic solutes the degree of separation is influenced mainly by electrostatic exclusion, while for organic solutes the removal depends mainly upon the solute radius and molecular structure. In order to provide a better understanding of rejection mechanisms for the RO and NF membranes, the ratio of solute radius (r(i,s)) to effective membrane pore radius (r(p)) was employed to compare rejections. An empirical relation for the dependence of the rejection of organic compounds on the ratio r(i,s)/r(p) is presented. The rejection for organic compounds is over 75% when r(i,s)/r(p) is greater than 0.8. In addition, the rejection of organic compounds is examined using the extended Nernst-Planck equation coupled with a steric hindrance model. The transport of organic solutes is controlled mainly by diffusion for the compounds that have a high r(i,s)/r(p) ratio, while convection is dominant for compounds that have a small r(i,s)/r(p) ratio. c2005 Elsevier B.V. All rights reserved.

  13. Removal of organic contaminants by RO and NF membranes

    NASA Technical Reports Server (NTRS)

    Yoon, Yeomin; Lueptow, Richard M.

    2005-01-01

    Rejection characteristics of organic and inorganic compounds were examined for six reverse osmosis (RO) membranes and two nanofiltration (NF) membranes that are commercially available. A batch stirred-cell was employed to determine the membrane flux and the solute rejection for solutions at various concentrations and different pH conditions. The results show that for ionic solutes the degree of separation is influenced mainly by electrostatic exclusion, while for organic solutes the removal depends mainly upon the solute radius and molecular structure. In order to provide a better understanding of rejection mechanisms for the RO and NF membranes, the ratio of solute radius (r(i,s)) to effective membrane pore radius (r(p)) was employed to compare rejections. An empirical relation for the dependence of the rejection of organic compounds on the ratio r(i,s)/r(p) is presented. The rejection for organic compounds is over 75% when r(i,s)/r(p) is greater than 0.8. In addition, the rejection of organic compounds is examined using the extended Nernst-Planck equation coupled with a steric hindrance model. The transport of organic solutes is controlled mainly by diffusion for the compounds that have a high r(i,s)/r(p) ratio, while convection is dominant for compounds that have a small r(i,s)/r(p) ratio. c2005 Elsevier B.V. All rights reserved.

  14. Ecological removal of recalcitrant phenolic compounds of treated olive mill wastewater by Pediococcus pentosaceus.

    PubMed

    Ben Othman, N; Ayed, L; Assas, N; Kachouri, F; Hammami, M; Hamdi, M

    2008-05-01

    Treatment of olive mill wastewater by different biological process led to an important decrease of organic compounds but the black coloration due to the recalcitrant phenolic compounds persists. Experimental design using fractional factorial plan showed that, among the seven studied factors, yeast extract, dilution and glucose exhibited a positive effect on Pediococcus pentosaceus growth and treated olive mill wastewater (TOMW) decolourisation. Optimization of influent factors showed that 2.5 and 1g/l are the suitable concentrations of glucose and yeast extract, respectively. Optimum TOMW decolourisation was reached when TOMW was diluted to 2.5 initial OD390 value. The growth of P. pentosaceus on TOMW led to high molecular weight phenolic compounds removal as shown by the sephadex G-50 chromatogram. Simple phenolic compound removal was also observed. Bacterial growth on TOMW induced an ecological removal of recalcitrant phenolic compounds without chemical sludge production.

  15. New methodology for removing carbonyl compounds from sweet wines.

    PubMed

    Blasi, Mélanie; Barbe, Jean-Christophe; Maillard, Bernard; Dubourdieu, Denis; Deleuze, Hervé

    2007-12-12

    Sweet white wines from botrytized grapes present high SO2 levels because of their high sulfur dioxide binding power. The objective of this work was to develop a new method for reducing this binding power by partially eliminating the carbonyl compounds naturally present in these wines that are responsible for this phenomenon. A selective liquid-solid removal technique was developed. Phenylsulfonylhydrazine was selected as the best candidate for removing carbonyl compounds. Its reactivity in the presence or absence of sulfur dioxide was verified in model media containing acetaldehyde, pyruvic acid, and 2-oxoglutaric acid, some of the main carbonyl compounds responsible for the SO2 binding power of sweet wines. The scavenging function was grafted on porous polymer supports, and its efficiency was evaluated in model wines. Dependent upon the supports used, different quantities of carbonyl compounds (over 90% in some cases) were removed in a few days. The presence of sulfur dioxide delayed removal without changing its quality. The results obtained showed that the method removed carbonyl compounds efficiently and was applicable to wines at any stage in winemaking.

  16. Organic compounds in concrete from demolition works.

    PubMed

    Van Praagh, M; Modin, H; Trygg, J

    2015-11-01

    This study aims to verify the effect of physically removing the outer surface of contaminated concrete on total contents and on potential mobility of pollutants by means of leaching tests. Reclaimed concrete from 3 industrial sites in Sweden were included: A tar impregnated military storage, a military tar track-depot, as well as concrete constructions used for disposing of pesticide production surplus and residues. Solid materials and leachates from batch and column leaching tests were analysed for metals, Cl, F, SO4, DOC and contents of suspected organic compounds (polycyclic aromatic hydrocarbons, PAH, and pesticides/substances for pesticide production such as phenoxy acids, chlorophenols and chlorocresols, respectively). In case of PAH contaminated concrete, results indicate that removing 1 or 5 mm of the surface lead to total concentrations below the Swedish guidelines for recycling of aggregates and soil in groundwork constructions. 3 out of 4 concrete samples contaminated with pesticides fulfilled Swedish guidelines for contaminated soil. Results from batch and column leaching tests indicated, however, that concentrations above environmental quality standards for certain PAH and phenoxy acids, respectively, might occur at site when the crushed concrete is recycled in groundwork constructions. As leaching tests engaged in the study deviated from leaching test standards with a limited number of samples, the potential impact of the leaching tests' equipment on measured PAH and pesticide leachate concentrations has to be evaluated in future work.

  17. Process for removing heavy metal compounds from heavy crude oil

    DOEpatents

    Cha, Chang Y.; Boysen, John E.; Branthaver, Jan F.

    1991-01-01

    A process is provided for removing heavy metal compounds from heavy crude oil by mixing the heavy crude oil with tar sand; preheating the mixture to a temperature of about 650.degree. F.; heating said mixture to up to 800.degree. F.; and separating tar sand from the light oils formed during said heating. The heavy metals removed from the heavy oils can be recovered from the spent sand for other uses.

  18. Biodegradation of halogenated organic compounds.

    PubMed Central

    Chaudhry, G R; Chapalamadugu, S

    1991-01-01

    In this review we discuss the degradation of chlorinated hydrocarbons by microorganisms, emphasizing the physiological, biochemical, and genetic basis of the biodegradation of aliphatic, aromatic, and polycyclic compounds. Many environmentally important xenobiotics are halogenated, especially chlorinated. These compounds are manufactured and used as pesticides, plasticizers, paint and printing-ink components, adhesives, flame retardants, hydraulic and heat transfer fluids, refrigerants, solvents, additives for cutting oils, and textile auxiliaries. The hazardous chemicals enter the environment through production, commercial application, and waste. As a result of bioaccumulation in the food chain and groundwater contamination, they pose public health problems because many of them are toxic, mutagenic, or carcinogenic. Although synthetic chemicals are usually recalcitrant to biodegradation, microorganisms have evolved an extensive range of enzymes, pathways, and control mechanisms that are responsible for catabolism of a wide variety of such compounds. Thus, such biological degradation can be exploited to alleviate environmental pollution problems. The pathways by which a given compound is degraded are determined by the physical, chemical, and microbiological aspects of a particular environment. By understanding the genetic basis of catabolism of xenobiotics, it is possible to improve the efficacy of naturally occurring microorganisms or construct new microorganisms capable of degrading pollutants in soil and aquatic environments more efficiently. Recently a number of genes whose enzyme products have a broader substrate specificity for the degradation of aromatic compounds have been cloned and attempts have been made to construct gene cassettes or synthetic operons comprising these degradative genes. Such gene cassettes or operons can be transferred into suitable microbial hosts for extending and custom designing the pathways for rapid degradation of recalcitrant

  19. Tropospheric volatile organic compounds in China.

    PubMed

    Guo, H; Ling, Z H; Cheng, H R; Simpson, I J; Lyu, X P; Wang, X M; Shao, M; Lu, H X; Ayoko, G; Zhang, Y L; Saunders, S M; Lam, S H M; Wang, J L; Blake, D R

    2017-01-01

    Photochemical smog, characterized by high concentrations of ozone (O3) and fine particles (PM2.5) in the atmosphere, has become one of the top environmental concerns in China. Volatile organic compounds (VOCs), one of the key precursors of O3 and secondary organic aerosol (SOA) (an important component of PM2.5), have a critical influence on atmospheric chemistry and subsequently affect regional and global climate. Thus, VOCs have been extensively studied in many cities and regions in China, especially in the North China Plain, the Yangtze River Delta and the Pearl River Delta regions where photochemical smog pollution has become increasingly worse over recent decades. This paper reviews the main studies conducted in China on the characteristics and sources of VOCs, their relationship with O3 and SOA, and their removal technology. This paper also provides an integrated literature review on the formulation and implementation of effective control strategies of VOCs and photochemical smog, as well as suggestions for future directions of VOCs study in China.

  20. Organic compounds in hydraulic fracturing fluids and wastewaters: A review.

    PubMed

    Luek, Jenna L; Gonsior, Michael

    2017-10-15

    High volume hydraulic fracturing (HVHF) of shale to stimulate the release of natural gas produces a large quantity of wastewater in the form of flowback fluids and produced water. These wastewaters are highly variable in their composition and contain a mixture of fracturing fluid additives, geogenic inorganic and organic substances, and transformation products. The qualitative and quantitative analyses of organic compounds identified in HVHF fluids, flowback fluids, and produced waters are reviewed here to communicate knowledge gaps that exist in the composition of HVHF wastewaters. In general, analyses of organic compounds have focused on those amenable to gas chromatography, focusing on volatile and semi-volatile oil and gas compounds. Studies of more polar and non-volatile organic compounds have been limited by a lack of knowledge of what compounds may be present as well as quantitative methods and standards available for analyzing these complex mixtures. Liquid chromatography paired with high-resolution mass spectrometry has been used to investigate a number of additives and will be a key tool to further research on transformation products that are increasingly solubilized through physical, chemical, and biological processes in situ and during environmental contamination events. Diverse treatments have been tested and applied to HVHF wastewaters but limited information has been published on the quantitative removal of individual organic compounds. This review focuses on recently published information on organic compounds identified in flowback fluids and produced waters from HVHF. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Methods of making organic compounds by metathesis

    DOEpatents

    Abraham, Timothy W.; Kaido, Hiroki; Lee, Choon Woo; Pederson, Richard L.; Schrodi, Yann; Tupy, Michael John

    2015-09-01

    Described are methods of making organic compounds by metathesis chemistry. The methods of the invention are particularly useful for making industrially-important organic compounds beginning with starting compositions derived from renewable feedstocks, such as natural oils. The methods make use of a cross-metathesis step with an olefin compound to produce functionalized alkene intermediates having a pre-determined double bond position. Once isolated, the functionalized alkene intermediate can be self-metathesized or cross-metathesized (e.g., with a second functionalized alkene) to produce the desired organic compound or a precursor thereto. The method may be used to make bifunctional organic compounds, such as diacids, diesters, dicarboxylate salts, acid/esters, acid/amines, acid/alcohols, acid/aldehydes, acid/ketones, acid/halides, acid/nitriles, ester/amines, ester/alcohols, ester/aldehydes, ester/ketones, ester/halides, ester/nitriles, and the like.

  2. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, Jr., Lawrence A.; Arganbright, Robert P.; Hearn, Dennis

    1993-01-01

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C.sub.2 to C.sub.10 olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80.degree. C. to 500.degree. C., using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene to about the mid point of the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms.

  3. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

    1994-06-14

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C[sub 2] to C[sub 10] olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80 C to 500 C, using as the catalyst a molecular sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms. 1 fig.

  4. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

    1993-09-07

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C[sub 2] to C[sub 10] olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80 C to 500 C, using as the catalyst a molecular sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene to about the mid point of the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms. 1 figures.

  5. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, Jr., Lawrence A.

    1989-01-01

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C.sub.2 to C.sub.10 olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80.degree. C. to 500.degree. C., using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms.

  6. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, L.A. Jr.

    1989-07-18

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C[sub 2] to C[sub 10] olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80 C to 500 C, using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms. 1 fig.

  7. Alkylation of organic aromatic compounds

    DOEpatents

    Smith, Jr., Lawrence A.; Arganbright, Robert P.; Hearn, Dennis

    1994-01-01

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C.sub.2 to C.sub.10 olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80.degree. C. to 500.degree. C., using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms.

  8. Bibliography of work on the photocatalytic removal of hazardous compounds from water and air

    SciTech Connect

    Blake, D.M.

    1994-05-01

    This is a bibliography of information in the open literature on work that has been done to date on the photocatalytic oxidation of compounds, principally organic compounds. The goal of the listing is removing hazardous oompounds from water or air. It contains lists of substances and literature citations. The bibliography includes information obtained through the middle of 1993 and some selected references for the balance of that year.

  9. Thermodynamic properties of organic iodine compounds

    NASA Astrophysics Data System (ADS)

    Richard, Laurent; Gaona, Xavier

    2011-11-01

    A critical evaluation has been made of the thermodynamic properties reported in the literature for 43 organic iodine compounds in the solid, liquid, or ideal gas state. These compounds include aliphatic, cyclic and aromatic iodides, iodophenols, iodocarboxylic acids, and acetyl and benzoyl iodides. The evaluation has been made on the basis of carbon number systematics and group additivity relations, which also allowed to provide estimates of the thermodynamic properties of those compounds for which no experimental data were available. Standard molal thermodynamic properties at 25 °C and 1 bar and heat capacity coefficients are reported for 13 crystalline, 29 liquid, and 39 ideal gas organic iodine compounds, which can be used to calculate the corresponding properties as a function of temperature and pressure. Values derived for the standard molal Gibbs energy of formation at 25 °C and 1 bar of these crystalline, liquid, and ideal gas organic iodine compounds have subsequently been combined with either solubility measurements or gas/water partition coefficients to obtain values for the standard partial molal Gibbs energies of formation at 25 °C and 1 bar of 32 aqueous organic iodine compounds. The thermodynamic properties of organic iodine compounds calculated in the present study can be used together with those for aqueous inorganic iodine species to predict the organic/inorganic speciation of iodine in marine sediments and petroleum systems, or in the near- and far-field of nuclear waste repositories.

  10. Organic electronic devices using phthalimide compounds

    DOEpatents

    Hassan, Azad M.; Thompson, Mark E.

    2010-09-07

    Organic electronic devices comprising a phthalimide compound. The phthalimide compounds disclosed herein are electron transporters with large HOMO-LUMO gaps, high triplet energies, large reduction potentials, and/or thermal and chemical stability. As such, these phthalimide compounds are suitable for use in any of various organic electronic devices, such as OLEDs and solar cells. In an OLED, the phthalimide compounds may serve various functions, such as a host in the emissive layer, as a hole blocking material, or as an electron transport material. In a solar cell, the phthalimide compounds may serve various functions, such as an exciton blocking material. Various examples of phthalimide compounds which may be suitable for use in the present invention are disclosed.

  11. Organic electronic devices using phthalimide compounds

    DOEpatents

    Hassan, Azad M.; Thompson, Mark E.

    2013-03-19

    Organic electronic devices comprising a phthalimide compound. The phthalimide compounds disclosed herein are electron transporters with large HOMO-LUMO gaps, high triplet energies, large reduction potentials, and/or thermal and chemical stability. As such, these phthalimide compounds are suitable for use in any of various organic electronic devices, such as OLEDs and solar cells. In an OLED, the phthalimide compounds may serve various functions, such as a host in the emissive layer, as a hole blocking material, or as an electron transport material. In a solar cell, the phthalimide compounds may serve various functions, such as an exciton blocking material. Various examples of phthalimide compounds which may be suitable for use in the present invention are disclosed.

  12. Organic electronic devices using phthalimide compounds

    DOEpatents

    Hassan, Azad M.; Thompson, Mark E.

    2012-10-23

    Organic electronic devices comprising a phthalimide compound. The phthalimide compounds disclosed herein are electron transporters with large HOMO-LUMO gaps, high triplet energies, large reduction potentials, and/or thermal and chemical stability. As such, these phthalimide compounds are suitable for use in any of various organic electronic devices, such as OLEDs and solar cells. In an OLED, the phthalimide compounds may serve various functions, such as a host in the emissive layer, as a hole blocking material, or as an electron transport material. In a solar cell, the phthalimide compounds may serve various functions, such as an exciton blocking material. Various examples of phthalimide compounds which may be suitable for use in the present invention are disclosed.

  13. Trace organics removal by advanced wastewater treatment

    SciTech Connect

    McCarty, P.L.; Reinhard, M.

    1980-07-01

    A statistical study was performed on data on trace organics removal at an advanced wastewater treatment plant in southern California. The log normal distribution was used for the statistical analysis. Among the substances investigated were: chemical oxygen demand, chloroethanes, chlorobenzenes, chloroethylenes, naphthalenes, xylenes, methylphthalates, butylphthalates, polychlorinated biphenyls, and lindane. Data for the period in which trickling filter effluent was the influent to the plant indicated removals of 90% or more, with small confidence intervals. During a period when activated sludge effluent was the plant influent, confidence intervals were wider; generally the quality of influent water improved but changes in advanced treatment effluent quality were variable.

  14. Microwave spectra of some volatile organic compounds

    NASA Technical Reports Server (NTRS)

    White, W. F.

    1975-01-01

    A computer-controlled microwave (MRR) spectrometer was used to catalog reference spectra for chemical analysis. Tables of absorption frequency, peak absorption intensity, and integrated intensity are included for 26 volatile organic compounds, all but one of which contain oxygen.

  15. VOLATILE ORGANIC COMPOUNDS AS EXPOSURE BIOMARKERS

    EPA Science Inventory

    Alveolar breath sampling and analysis can be extremely useful in exposure assessment studies involving volatile organic compounds (VOCs). Over recent years scientists from the US Environmental Protection Agency's National Exposure Research Laboratory have developed and refined...

  16. Energies of organic compounds. Final report

    SciTech Connect

    1995-07-01

    The objective of this research was to gain information on the energies of organic compounds and on the factors that control energies. The work involved calorimetric measurements of energy changes and theoretical studies of intramolecular interactions and molecular energies.

  17. VOLATILE ORGANIC COMPOUNDS AS EXPOSURE BIOMARKERS

    EPA Science Inventory

    Alveolar breath sampling and analysis can be extremely useful in exposure assessment studies involving volatile organic compounds (VOCs). Over recent years scientists from the US Environmental Protection Agency's National Exposure Research Laboratory have developed and refined...

  18. VOLATILE ORGANIC COMPOUNDS (VOCS) CHAPTER 31.

    EPA Science Inventory

    The term "volatile organic compounds' (VOCs) was originally coined to refer, as a class, to carbon-containing chemicals that participate in photochemical reactions in the ambient (outdoor) are. The regulatory definition of VOCs used by the U.S. EPA is: Any compound of carbon, ex...

  19. (CHINA) PERFLUORINATED ORGANIC COMPOUND EXPOSURE ASSESSMENT RESEARCH

    EPA Science Inventory

    A wide range of perfluorinated organic compounds (PFCs) has been used in a variety of industrial processes and consumer products. The most commonly studied PFCs include perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), but there are many more compounds in this c...

  20. PERFLUORINATED ORGANIC COMPOUND EXPOSURE ASSESSMENT RESEARCH

    EPA Science Inventory

    A wide range of perfluorinated organic compounds (PFCs) has been used in a variety of industrial processes and consumer products. The most commonly studied PFCs include perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), but there are many more compounds in this c...

  1. VOLATILE ORGANIC COMPOUNDS (VOCS) CHAPTER 31.

    EPA Science Inventory

    The term "volatile organic compounds' (VOCs) was originally coined to refer, as a class, to carbon-containing chemicals that participate in photochemical reactions in the ambient (outdoor) are. The regulatory definition of VOCs used by the U.S. EPA is: Any compound of carbon, ex...

  2. PERFLUORINATED ORGANIC COMPOUND EXPOSURE ASSESSMENT RESEARCH

    EPA Science Inventory

    A wide range of perfluorinated organic compounds (PFCs) has been used in a variety of industrial processes and consumer products. The most commonly studied PFCs include perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), but there are many more compounds in this c...

  3. (CHINA) PERFLUORINATED ORGANIC COMPOUND EXPOSURE ASSESSMENT RESEARCH

    EPA Science Inventory

    A wide range of perfluorinated organic compounds (PFCs) has been used in a variety of industrial processes and consumer products. The most commonly studied PFCs include perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), but there are many more compounds in this c...

  4. Volatile organic compound emissions from silage systems

    USDA-ARS?s Scientific Manuscript database

    As a precursor to smog, emission of volatile organic compounds (VOCs) to the atmosphere is an environmental concern in some regions. The major source from farms is silage, with emissions coming from the silo face, mixing wagon, and feed bunk. The major compounds emitted are alcohols with other impor...

  5. Removal rates of dissolved munitions compounds in seawater.

    PubMed

    Smith, Richard W; Vlahos, Penny; Tobias, Craig; Ballentine, Mark; Ariyarathna, Thivanka; Cooper, Christopher

    2013-08-01

    The historical exposure of coastal marine systems to munitions compounds is of significant concern due to the global distribution of impacted sites and known toxicological effects of nitroaromatics. In order to identify specific coastal regions where persistence of these chemicals should be of concern, it is necessary to experimentally observe their behavior under a variety of realistic oceanographic conditions. Here, we conduct a mesocosm scale pulse addition experiment to document the behavior of two commonly used explosives, 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in simulated marine systems containing water and sediments collected from Long Island Sound, CT. The addition of sediments and sediment grain-size had a major influence on the loss rates of all compounds detected. RDX and reduced TNT products were removed from seawater only in the presence of sediment, and TNT degraded significantly faster in the presence of sediment. Both compounds were removed from the system faster with decreasing grain-size. Based on these findings and a thorough review of the literature, we hypothesize that in addition to bacterial abundance and nutrient availability, TNT removal rates in coastal marine waters may be controlled by sorption and rapid surface-mediated bacterial transformation, while RDX removal rates are controlled by diffusion into sedimentary anoxic regions and subsequent anaerobic bacterial breakdown. A comparison of published removal rates of RDX and TNT highlights the extreme variability in measured degradation rates and identifies physicochemical variables that covary with the breakdown of these munitions compounds. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Atmospheric Chemistry of Micrometeoritic Organic Compounds

    NASA Technical Reports Server (NTRS)

    Kress, M. E.; Belle, C. L.; Pevyhouse, A. R.; Iraci, L. T.

    2011-01-01

    Micrometeorites approx.100 m in diameter deliver most of the Earth s annual accumulation of extraterrestrial material. These small particles are so strongly heated upon atmospheric entry that most of their volatile content is vaporized. Here we present preliminary results from two sets of experiments to investigate the fate of the organic fraction of micrometeorites. In the first set of experiments, 300 m particles of a CM carbonaceous chondrite were subject to flash pyrolysis, simulating atmospheric entry. In addition to CO and CO2, many organic compounds were released, including functionalized benzenes, hydrocarbons, and small polycyclic aromatic hydrocarbons. In the second set of experiments, we subjected two of these compounds to conditions that simulate the heterogeneous chemistry of Earth s upper atmosphere. We find evidence that meteor-derived compounds can follow reaction pathways leading to the formation of more complex organic compounds.

  7. Possible complex organic compounds on Mars.

    PubMed

    Kobayashi, K; Sato, T; Kajishima, S; Kaneko, T; Ishikawa, Y; Saito, T

    1997-01-01

    It is suggested that primitive Mars had somehow similar environments as primitive Earth. If life was born on the primitive earth using organic compounds which were produced from the early Earth environment, the same types of organic compounds were also formed on primitive Mars. Such organic compounds might have been preserved on Mars still now. We are studying possible organic formation on primitive and present Mars. A gaseous mixture of CO2, CO, N2 and H2O with various mixing ratios were irradiated with high energy protons (major components of cosmic rays). Hydrogen cyanide and formaldehyde were detected among volatile products, and yellow-brown-colored water-soluble non-volatile substances were produced, which gave amino acids after acid-hydrolysis. Major part of "amino acid precursors" were not simple molecules like aminonitriles, but complex compounds which eluted earlier than free amino acids in cation-exchange HPLC. These organic compounds should be major targets in the future Mars mission. Strategy for the detection of the complex organics on Mars will be discussed.

  8. Removal of phenolic compounds from wastewaters using soybean peroxidase

    SciTech Connect

    Wright, H.; Nicell, J.A.

    1996-11-01

    Toxic and odiferous phenolic compounds are present in wastewaters generated by a variety of industries including petroleum refining, plastics, resins, textiles, and iron and steel manufacturing among others. Due to its commercial availability in purified form, its useful presence in raw plant material, and its proven ability to remove a variety of phenolic contaminants from wastewaters over a wide range of pH and temperature, horseradish peroxidase (HRP) appears to be the peroxidase enzyme of choice in enzymatic wastewater treatment studies. Problems with HRP catalyzed phenol removal, however, include the formation of toxic soluble reaction by-products, the cost of the enzyme, and costs associated with disposal of the phenolic precipitate generated. Enzyme costs are incurred because the enzyme is inactivated during the phenol removal process by various side reactions. While recent work has shown that enzyme inactivation can be reduced using chemical additives, the problem of enzyme cost could be circumvented by using a less expensive source of enzyme. In 1991, the seed coat of the soybean was identified as a very rich source of peroxidase enzyme. Since the seed coat of the soybean is a waste product of the soybean food industry, soybean peroxidase (SBP) has the potential of being a cost effective alternative to HRP in wastewater treatment. In this study, SBP is characterized in terms of its catalytic activity, its stability, and its ability to promote removal of phenolic compounds from synthetic wastewaters. Results obtained are discussed and compared to similar investigations using HRP.

  9. Photocatalytic oxidation of organic compounds on Mars

    NASA Technical Reports Server (NTRS)

    Chun, S. F. S.; Pang, K. D.; Cutts, J. A.; Ajello, J. M.

    1978-01-01

    Ultraviolet-stimulated catalytic oxidation is proposed as a mechanism for the destruction of organic compounds on Mars. The process involves the presence of gaseous oxygen, UV radiation, and a catalyst (titanium dioxide), and all three of these have been found to be present in the Martian environment. Therefore it seems plausible that UV-stimulated oxidation of organics is responsible for degrading organic molecules into inorganic end products.

  10. Photocatalytic oxidation of organic compounds on Mars

    NASA Technical Reports Server (NTRS)

    Chun, S. F. S.; Pang, K. D.; Cutts, J. A.; Ajello, J. M.

    1978-01-01

    Ultraviolet-stimulated catalytic oxidation is proposed as a mechanism for the destruction of organic compounds on Mars. The process involves the presence of gaseous oxygen, UV radiation, and a catalyst (titanium dioxide), and all three of these have been found to be present in the Martian environment. Therefore it seems plausible that UV-stimulated oxidation of organics is responsible for degrading organic molecules into inorganic end products.

  11. Reflectance spectroscopy of organic compounds: 1. Alkanes

    USGS Publications Warehouse

    Clark, R.N.; Curchin, J.M.; Hoefen, T.M.; Swayze, G.A.

    2009-01-01

    Reflectance spectra of the organic compounds comprising the alkane series are presented from the ultraviolet to midinfrared, 0.35 to 15.5 /??m. Alkanes are hydrocarbon molecules containing only single carbon-carbon bonds, and are found naturally on the Earth and in the atmospheres of the giant planets and Saturn's moon, Titan. This paper presents the spectral properties of the alkanes as the first in a series of papers to build a spectral database of organic compounds for use in remote sensing studies. Applications range from mapping the environment on the Earth, to the search for organic molecules and life in the solar system and throughout the. universe. We show that the spectral reflectance properties of organic compounds are rich, with major diagnostic spectral features throughout the spectral range studied. Little to no spectral change was observed as a function of temperature and only small shifts and changes in the width of absorption bands were observed between liquids and solids, making remote detection of spectral properties throughout the solar system simpler. Some high molecular weight organic compounds contain single-bonded carbon chains and have spectra similar to alkanes even ' when they fall into other families. Small spectral differences are often present allowing discrimination among some compounds, further illustrating the need to catalog spectral properties for accurate remote sensing identification with spectroscopy.

  12. [Mechanisms of removing red tide organisms by organo-clays].

    PubMed

    Cao, Xi-Hua; Song, Xiu-Xian; Yu, Zhi-Ming; Wang, Kui

    2006-08-01

    We tested the influence of the preparation conditions of the quaternary ammonium compounds (QACs) modified clays on their capacities to remove red tide organisms, then discussed the mechanisms of the organo-clays removing red tide organisms. Hexadecyltrimethylammonium (HDTMA) improved the capacity of clays to flocculate red tide algae, and the HDTMA in metastable state enhanced the toxicity of the clay complexes to algae. The capacities of the organo-clays correlated with the toxicity and the adsorbed amount of the QACs used in clays modification, but as the incubation time was prolonged the stability of the organo-clays was improved and the algal removal efficiencies of the clay complexes decreased. When the adsorbed HDTMA was arranged in different clays in which the spatial resistance was different, there was more HDTMA in metastable state in the three-layer montmorillonite. Because of the homo-ion effect the bivalent or trivalent metal ions induced more HDTMA in metastable state and the corresponding organo-clays had high capacities to remove red tide organisms. When the reaction temperature was 60 degrees C the adsorbed HDTMA was easily arranged on cation exchange sites, if the temperature rose or fell the metastable HDTMA would increase so that the capacity of the clays was improved.

  13. Multiple microbial activities for volatile organic compounds reduction by biofiltration.

    PubMed

    Civilini, Marcello

    2006-07-01

    In the northeast of Italy, high volatile organic carbon (VOC) emissions originate from small-medium companies producing furniture. In these conditions it is difficult to propose a single, efficient, and economic system to reduce pollution. Among the various choices, the biofiltration method could be a good solution, because microbial populations possess multiple VOC degradation potentials used to oxidize these compounds to CO2. Starting from the air emissions of a typical industrial wood-painting plant, a series of experiments studied in vitro microbial degradation of each individual VOC. Isolated strains were then added to a laboratory-scale biofiltration apparatus filled with an organic matrix, and the different VOC behavior demonstrated the potential of single and/or synergic microbial removal actions. When a single substrate was fed, the removal efficiency of a Pseudomonas aeruginosa inoculated reactor was 1.1, 1.17, and 0.33 g m(-3) hr(-1), respectively, for xylene, toluene, and ethoxy propyl acetate. A VOC mixture composed of butyl acetate, ethyl acetate, diacetin alcohol, ethoxy propanol acetate, methyl ethyl ketone, methyl isobutyl ketone, toluene, and xylene was then fed into a 2-m(3) reactor treating 100 m3 hr(-1) of contaminated air. The reactor was filled with the same mixture of organic matrix, enriched with all of the isolated strains together. During reactor study, different VOC loading rates were used, and the behavior was evaluated continuously. After a short acclimation period, the removal efficiency was > 65% at VOC load of 150-200 g m(-3) hr(-1). Quantification of removal efficiencies and VOC speciation confirmed the relationship among removal efficiencies, compound biodegradability, and the dynamic transport of each mixture component within the organic matrix. Samples of the fixed bed were withdrawn at different intervals and the heterogeneous microbial community evaluated for both total and differential compound counts.

  14. Hazardous organic compounds in groundwater near Tehran automobile industry.

    PubMed

    Dobaradaran, Sina; Mahvi, Amir Hossein; Nabizadeh, Ramin; Mesdaghinia, Alireza; Naddafi, Kazem; Yunesian, Masoud; Rastkari, Noushin; Nazmara, Shahrokh

    2010-11-01

    Potential of groundwater contamination by trichloroethylene (TCE) and other volatile organic compounds VOCs near car industry was conducted in this study. TCE, PCE, toluene, xylene, dichloromethane, cyclohexane, n-hexane and n-pentane were detected in all groundwaters. Mean TCE levels in groundwater ranged from 124.37 to 1,035.9 μg L⁻¹ with maximum level of 1,345.7 μg L⁻¹. Due to the data obtained from conventional wastewater treatment in car factory the TCE removal efficiency was only 24 percent which necessitates the TCE removal by advanced treatment processes before the use of well water.

  15. Origin of organic compounds in carbonaceous chondrites

    NASA Astrophysics Data System (ADS)

    Cronin, J. R.

    Carbonaceous chondrites, a class of primitive meteorite, have long been known to contain their complement of carbon largely in the form of organic, i.e., hydrocarbon-related, matter. Both discrete organic compounds and an insoluble, macromolecular material are present. Several characteristics of these materials provide evidence for their abiotic origin. The principal formation hypothesis have invoked chemistry occurring either in the solar nebula or on the parent body. However, recent stable isotope analyses of the meteorite carboxylic acids and amino acids indicate that they may be related to interstellar cloud compounds. These results suggest a formation scheme in which interstellar compounds were incorporated into the parent body and subsequently converted to the present suite of meteorite organics by the hydrothermal process believed to have formed the clay minerals of the meteorite matrix.

  16. Catalyst for Oxidation of Volatile Organic Compounds

    NASA Technical Reports Server (NTRS)

    Wood, George M. (Inventor); Upchurch, Billy T. (Inventor); Schryer, David R. (Inventor); Davis, Patricia P. (Inventor); Kielin, Erik J. (Inventor); Brown, Kenneth G. (Inventor); Schyryer, Jacqueline L. (Inventor); DAmbrosia, Christine M. (Inventor)

    2000-01-01

    Disclosed is a process for oxidizing volatile organic compounds to carbon dioxide and water with the minimal addition of energy. A mixture of the volatile organic compound and an oxidizing agent (e.g. ambient air containing the volatile organic compound) is exposed to a catalyst which includes a noble metal dispersed on a metal oxide which possesses more than one oxidation state. Especially good results are obtained when the noble metal is platinum, and the metal oxide which possesses more than one oxidation state is tin oxide. A promoter (i.e., a small amount of an oxide of a transition series metal) may be used in association with the tin oxide to provide very beneficial results.

  17. Process for removal of sulfur compounds from fuel gases

    DOEpatents

    Moore, Raymond H.; Stegen, Gary E.

    1978-01-01

    Fuel gases such as those produced in the gasification of coal are stripped of sulfur compounds and particulate matter by contact with molten metal salt. The fuel gas and salt are intimately mixed by passage through a venturi or other constriction in which the fuel gas entrains the molten salt as dispersed droplets to a gas-liquid separator. The separated molten salt is divided into a major and a minor flow portion with the minor flow portion passing on to a regenerator in which it is contacted with steam and carbon dioxide as strip gas to remove sulfur compounds. The strip gas is further processed to recover sulfur. The depleted, minor flow portion of salt is passed again into contact with the fuel gas for further sulfur removal from the gas. The sulfur depleted, fuel gas then flows through a solid absorbent for removal of salt droplets. The minor flow portion of the molten salt is then recombined with the major flow portion for feed to the venturi.

  18. Removal of cyanides by complexation with ferrous compounds

    SciTech Connect

    Varuntanya, C.P.; Zabban, W.

    1995-12-31

    Alkaline chlorination, an oxidation process with chlorine (Cl{sub 2}) or hypochlorite (ClO{sup {minus}}), is the most widely accepted method of cyanide treatment. However, removal of cyanide from wastewater to the extent required by the effluent limits imposed by Federal and State regulatory authorities is practically impossible, especially when the majority of the cyanide is present as an iron-cyanide complex. One potential treatment method being further investigated uses ferrous (Fe{sup 2+}) compounds to react with free and complex cyanide ions and produce insoluble iron-cyanide complexes. However, sludges generated by this treatment method contain cyanide wastes which may be considered a hazardous waste by the US Environmental Protection Agency (US EPA). The studies reported in this paper demonstrate that ferrous (Fe{sup 2+}) precipitation can remove cyanide ions (both free and complex) to a concentration within the range of 1 to 2 mg/L. The wastewaters utilized in these tests were collected from a coke plant facility. Synthetic cyanide solutions were used in the studied as well. Ferrous compounds used in the studies included commercial-grade ferrous sulfate, commercial-grade ferrous chloride, and spent pickle liquor (containing ferrous ion). The desired effluent quality was successfully attained in the treatment of the above-mentioned wastewaters by using ferrous compounds as well as spent pickle liquor.

  19. Volatile and semivolatile organic compounds in laboratory ...

    EPA Pesticide Factsheets

    Speciated volatile organic compounds (VOCs) and organic fine particulate matter (PM2.5) mass emission factors were determined from laboratory peat fire experiments. Peat samples originated from two wildlife reserves located near the coast of North Carolina, U.S. Gas and particulate organics were quantified by gas chromatography/mass spectrometry and by high pressure liquid chromatography. Hazardous air pollutants (HAPs) accounted for a large fraction (~60 %) of the speciated VOC emissions from peat burning, including large contributions of acetaldehyde, formaldehyde, benzene, toluene, and chloromethane. Speciated organic PM2.5 mass was dominated by the following compound classes: organic acids, levoglucosan, n-alkanes, and n-alkenes. Emission factors for PM2.5 organic acids including n-alkanoic acids, n-alkenoic acids, n-alkanedioic acids, and aromatic acids were reported for the first time for peat burning, representing the largest fraction of organic carbon (OC) mass (11-12 %) of all speciated compound classes measured in this work. Levoglucosan contributed 2-3 % of the OC mass, while methoxyphenols represented 0.2-0.3 % of the OC mass on a carbon mass basis. Retene was the most abundant particulate phase polycyclic aromatic hydrocarbon. Total HAP VOC and particulate polycyclic aromatic hydrocarbon emissions from a 2008 peat wildfire in North Carolina were estimated, suggesting that peat fires can contribute a large fraction of state-wide HAP emissions. This p

  20. Removal of organic magnesium in coccolithophore calcite

    NASA Astrophysics Data System (ADS)

    Blanco-Ameijeiras, S.; Lebrato, M.; Stoll, H. M.; Iglesias-Rodriguez, M. D.; Méndez-Vicente, A.; Sett, S.; Müller, M. N.; Oschlies, A.; Schulz, K. G.

    2012-07-01

    Coccolithophore calcite refers to the plates of calcium carbonate (CaCO3) produced by the calcifying phytoplankton, coccolithophores. The empirical study of the elemental composition has a great potential in the development of paleoproxies. However, the difficulties to separate coccolithophore carbonates from organic phases hamper the investigation of coccoliths magnesium to calcium ratios (Mg/Ca) in biogeochemical studies. Magnesium (Mg) is found in organic molecules in the cells at concentrations up to 400 times higher than in inorganically precipitated calcite in present-day seawater. The aim of this study was to optimize a reliable procedure for organic Mg removal from coccolithophore samples to ensure reproducibility in measurements of inorganic Mg in calcite. Two baseline methods comprising organic matter oxidations with (1) bleach and (2) hydrogen peroxide (H2O2) were tested on synthetic pellets, prepared by mixing reagent grade CaCO3 with organic matter from the non-calcifying marine algae Chlorella autotrophica and measured with an ICP-AES (inductively coupled plasma-atomic emission spectrometer). Our results show that treatments with a reductive solution [using hydroxylamine-hydrochloride (NH2OH·HCl + NH4OH)] followed by three consecutive oxidations (using H2O2) yielded the best cleaning efficiencies, removing >99% of organic Mg in 24 h. P/Ca and Fe/Ca were used as indicators for organic contamination in the treated material. The optimized protocol was tested in dried coccolithophore pellets from batch cultures of Emiliania huxleyi, Calcidiscus leptoporus and Gephyrocapsa oceanica. Mg/Ca of treated coccolithophores were 0.151 ± 0.018, 0.220 ± 0.040, and 0.064 ± 0.023 mmol/mol, respectively. Comparison with Mg/Ca literature coccolith values, suggests a tight dependence on modern seawater Mg/Ca, which changes as a consequence of different seawater origins (<10%). The reliable determination of Mg/Ca and Sr/Ca, and the low levels of organic contamination

  1. Metastable Equilibria Among Aqueous Organic Compounds

    NASA Astrophysics Data System (ADS)

    Shock, E.; Shipp, J.; Yang, Z.; Gould, I. R.

    2011-12-01

    Metastable equilibrium states exist when reactions among a subset of compounds in a chemical system are reversible even though other irreversible reactions exist in the same system. The existence of metastable equilibrium among organic compounds was initially detected by comparing ratios of organic acid concentrations reported for oil-field brines (Shock, 1988, Geology 16, 886-890; Shock, 1989, Geology 17, 572-573), and calculating the same ratios for likely oxidation states determined by mineral assemblages and mixtures of hydrocarbons in coexisting petroleum (Shock, 1994, in: The Role of Organic Acids in Geological Processes, Springer). This led to the notion of extending the concept of metastable equilibrium states to explicitly account for petroleum compositions (Helgeson et al., 1993, GCA, 57, 3295-3339), which eventually yielded the concept of hydrolytic disproportionation of kerogens to produce petroleum and CO2(g) (Helgeson et al., 2009, GCA, 73, 594-695). Experimental tests of metastable equilibrium among organic compounds began with the identification of reversible reactions between alkanes and alkenes that are dependent on the H2 fugacity of the experimental system (Seewald, 1994, Nature 370, 285-287). These were followed with a comprehensive series of long-term experiments leading to the hypothesis that reversible reactions include alkanes, alkenes, alcohol, aldehydes, ketones and carboxylic acids (e.g., Seewald, 2001, GCA 65, 1641-1664; 2003, Nature 426, 327-333; McCollom & Seewald, 2003, GCA 67, 3645-3664). We have conducted sets of hydrothermal organic transformation experiments that test the extent to which these reactions are indeed reversible using aromatic and cyclic compounds. Results demonstrate reversibility for reactions among dibenzyl ketone, 1,3-diphenyl-2-propanol, 1,3-diphenylpropene and 1,3-diphenylpropane, as well as among methylcyclohexanes, methylcyclohexenes, methylcyclohexanols, methylcyclohexanones and methylcyclohexadienes. The

  2. Selective removal of organics for water reclamation

    NASA Technical Reports Server (NTRS)

    Murphy, Oliver J.; Hitchens, G. Duncan; Kaba, Lamine; Verostko, Charles E.

    1990-01-01

    Electrooxidation is a means of removing organic solutes directly from waste waters without the use of chemical expendables. The feasibility of the concept for oxidation of organic impurities common to urine, shower waters and space habitat humidity condensates was demonstrated. Electrooxidation of urine and waste water ersatz was experimentally demonstrated. The electrooxidation principle, reaction kinetics, efficiency, power, size, experimental test results and water reclamation applications are described. Process operating potentials and the use of anodic oxidation potentials that are sufficiently low to avoid oxygen formation and chloride oxidation are also described. The design of a novel electrochemical system that incorporates a proton exchange membrane (PEM) electrolyte is presented based on parametric test data and current fuel cell technology.

  3. Chlorinated organic compounds in urban river sediments

    SciTech Connect

    Soma, Y.; Shiraishi, H.; Inaba, K.

    1995-12-31

    Among anthropogenic chemicals, many chlorinated organic compounds have been used as insecticides and detected frequently as contaminants in urban river sediments so far. However, the number and total amount of chemicals produced commercially and used are increasing year by year, though each amount of chemicals is not so high. New types of contaminants in the environment may be detected by the use of newly developed chemicals. Chlorinated organic compounds in the urban river sediments around Tokyo and Kyoto, large cities in Japan, were surveyed and recent trends of contaminants were studied. Contaminants of the river sediments in industrial areas had a variety, but PCB (polychlorinated biphenyls) was detected in common in industrial areas. Concentration of PCB related well to the number of factories on both sides of rivers, although the use of PCB was stopped 20 years ago. In domestic areas, Triclosan (5-chloro-2-(2,4-dichlorophenoxy)-phenol) and Triclocarban (3,4,4{prime}-trichlorocarbanilide)(both are contained in soap or shampoo for fungicides), p-dichlorobenzene (insecticides for wears) and TCEP(tris-chloroethyl phosphate) were detected. EOX(extracted organic halogen) in the sediments was 5 to 10 times of chlorinated organic compounds detected by GC/MS. Major part of organic halogen was suggested to be included in chlorinated organics formed by bleaching or sterilization.

  4. Volatile organic compounds from leaves litter.

    PubMed

    Isidorov, Valery; Jdanova, Maria

    2002-09-01

    Qualitative composition of volatile emissions of litter of five species of deciduous trees was investigated by GC-MS. The list of identified substances contains more than 70 organic compounds of various classes. It was established that the composition of components emitted by the litter into the gas phase greatly differs from that of essential oils extracted by hydrodistillation from turned leaves collected from trees during fall. It is suggested that most compounds found in litter emissions are products of vital activity of microorganisms decomposing it. The reported data indicate that after the vegetative period is over the decomposition processes of litter are important seasonal sources of reactive organic compounds under the forest canopy.

  5. Catalytic Destruction Of Toxic Organic Compounds

    NASA Technical Reports Server (NTRS)

    Voecks, Gerald E.

    1990-01-01

    Proposed process disposes of toxic organic compounds in contaminated soil or carbon beds safely and efficiently. Oxidizes toxic materials without producing such other contaminants as nitrogen oxides. Using air, fuel, catalysts, and steam, system consumes less fuel and energy than decontamination processes currently in use. Similar process regenerates carbon beds used in water-treatment plants.

  6. Azodicarboxylates: synthesis and functionalization of organic compounds

    NASA Astrophysics Data System (ADS)

    Zhirov, A. M.; Aksenov, A. V.

    2014-06-01

    The data on transformations of dialkyl azodicarboxylates and their analogues involving various substrates are generalized. Nucleophilic addition and oxidation, pericyclic reactions and reactions occurring under the Mitsunobu reaction conditions are considered. Ample opportunities for application of these compounds in fine organic synthesis are shown. The bibliography includes 245 references. Dedicated to Academician B A Trofimov on the occasion of his 75th birthday.

  7. Catalytic Destruction Of Toxic Organic Compounds

    NASA Technical Reports Server (NTRS)

    Voecks, Gerald E.

    1990-01-01

    Proposed process disposes of toxic organic compounds in contaminated soil or carbon beds safely and efficiently. Oxidizes toxic materials without producing such other contaminants as nitrogen oxides. Using air, fuel, catalysts, and steam, system consumes less fuel and energy than decontamination processes currently in use. Similar process regenerates carbon beds used in water-treatment plants.

  8. Global Exposure Modelling of Semivolatile Organic Compounds

    NASA Astrophysics Data System (ADS)

    Guglielmo, F.; Lammel, G.; Maier-Reimer, E.

    2008-12-01

    Organic compounds which are persistent and toxic as the agrochemicals γ-hexachlorocyclohexane (γ-HCH, lindane) and dichlorodiphenyltrichloroethane (DDT) pose a hazard for the ecosystems. These compounds are semivolatile, hence multicompartmental substances and subject to long-range transport (LRT) in atmosphere and ocean. Being lipophilic, they accumulate in exposed organism tissues and biomagnify along food chains. The multicompartmental global fate and LRT of DDT and lindane in the atmosphere and ocean have been studied using application data for 1980, on a decadal scale using a model based on the coupling of atmosphere and (for the first time for these compounds) ocean General Circulation Models (ECHAM5 and MPI-OM). The model system encompasses furthermore 2D terrestrial compartments (soil and vegetation) and sea ice, a fully dynamic atmospheric aerosol (HAM) module and an ocean biogeochemistry module (HAMOCC5). Large mass fractions of the compounds are found in soil. Lindane is also found in comparable amount in ocean. DDT has the longest residence time in almost all compartments. The sea ice compartment locally almost inhibits volatilization from the sea. The air/sea exchange is also affected , up to a reduction of 35 % for DDT by partitioning to the organic phases (suspended and dissolved particulate matter) in the global oceans. Partitioning enhances vertical transport in the sea. Ocean dynamics are found to be more significant for vertical transport than sinking associated with particulate matter. LRT in the global environment is determined by the fast atmospheric circulation. Net meridional transport taking place in the ocean is locally effective mostly via western boundary currents, upon applications at mid- latitudes. The pathways of the long-lived semivolatile organic compounds studied include a sequence of several cycles of volatilisation, transport in the atmosphere, deposition and transport in the ocean (multihopping substances). Multihopping is

  9. HENRY'S LAW CONSTANTS AND MICELLAR PARTITIONING OF VOLATILE ORGANIC COMPOUNDS IN SURFACTANT SOLUTIONS

    EPA Science Inventory

    Partitioning of volatile organic compounds (VOCs) into surfactant micelles affects the apparent vapor-liquid equilibrium of VOCs in surfactant solutions. This partitioning will complicate removal of VOCs from surfactant solutions by standard separation processes. Headspace expe...

  10. HENRY'S LAW CONSTANTS AND MICELLAR PARTITIONING OF VOLATILE ORGANIC COMPOUNDS IN SURFACTANT SOLUTIONS

    EPA Science Inventory

    Partitioning of volatile organic compounds (VOCs) into surfactant micelles affects the apparent vapor-liquid equilibrium of VOCs in surfactant solutions. This partitioning will complicate removal of VOCs from surfactant solutions by standard separation processes. Headspace expe...

  11. Fate of Volatile Organic Compounds in Constructed Wastewater Treatment Wetlands

    USGS Publications Warehouse

    Keefe, S.H.; Barber, L.B.; Runkel, R.L.; Ryan, J.N.

    2004-01-01

    The fate of volatile organic compounds was evaluated in a wastewater-dependent constructed wetland near Phoenix, AZ, using field measurements and solute transport modeling. Numerically based volatilization rates were determined using inverse modeling techniques and hydraulic parameters established by sodium bromide tracer experiments. Theoretical volatilization rates were calculated from the two-film method incorporating physicochemical properties and environmental conditions. Additional analyses were conducted using graphically determined volatilization rates based on field measurements. Transport (with first-order removal) simulations were performed using a range of volatilization rates and were evaluated with respect to field concentrations. The inverse and two-film reactive transport simulations demonstrated excellent agreement with measured concentrations for 1,4-dichlorobenzene, tetrachloroethene, dichloromethane, and trichloromethane and fair agreement for dibromochloromethane, bromo-dichloromethane, and toluene. Wetland removal efficiencies from inlet to outlet ranged from 63% to 87% for target compounds.

  12. Biodesulfurization of refractory organic sulfur compounds in fossil fuels.

    PubMed

    Soleimani, Mehran; Bassi, Amarjeet; Margaritis, Argyrios

    2007-01-01

    The stringent new regulations to lower sulfur content in fossil fuels require new economic and efficient methods for desulfurization of recalcitrant organic sulfur. Hydrodesulfurization of such compounds is very costly and requires high operating temperature and pressure. Biodesulfurization is a non-invasive approach that can specifically remove sulfur from refractory hydrocarbons under mild conditions and it can be potentially used in industrial desulfurization. Intensive research has been conducted in microbiology and molecular biology of the competent strains to increase their desulfurization activity; however, even the highest activity obtained is still insufficient to fulfill the industrial requirements. To improve the biodesulfurization efficiency, more work is needed in areas such as increasing specific desulfurization activity, hydrocarbon phase tolerance, sulfur removal at higher temperature, and isolating new strains for desulfurizing a broader range of sulfur compounds. This article comprehensively reviews and discusses key issues, advances and challenges for a competitive biodesulfurization process.

  13. Evaluation of an Innovative Technology for Treatment of Water Contaminated with Perchlorate and Organic Compounds

    DTIC Science & Technology

    2009-03-26

    presence of other nonpolar molecules— water , of course, is very polar ). Hydrophobic compounds are readily removed by GAC, since GAC is a nonpolar ...as explosives. GAC is a conventional technology that is used to treat water contaminated with these non- polar organic contaminants. Research has...are a number of technologies that can cost effectively remove non- polar organic compounds from water . Specifically, as noted above, IX and T-GAC

  14. Removal of organic contaminants from lithographic materials

    NASA Astrophysics Data System (ADS)

    Lytle, Wayne M.

    One of the critical issues still facing the implementation of extreme ultraviolet lithography (EUVL) into mainstream manufacturing for integrated circuit (IC) production is cleanliness. EUV photons at 13.5 nm are easily absorbed by many species, including dust, thin-film layers, and other debris present in the path of the photons. Carrying out EUVL inside a vacuum helps reduce the amount of photon loss for illumination, however contamination in the sys- tem is unavoidable, especially due to carbon growth on the multilayer mirror collectors and to soft defects in the form of organic contamination on the mask. Traditional cleaning methods employ the use of wet chemicals to etch contamination off of a surface, however this is limited in the sub-micron range of contaminant particles due to lack of transport of sufficient liquid chemical to the surface in order to achieve satisfactory particle removal. According to the International Technology Roadmap for Semiconductors (ITRS), the photomask must be particle free at inspection below 30 nm. However, when analyzing the ability of traditional methods to meet the cleaning needs set forth by the ITRS, these methods fall short and often add more contamination to the surface targeted for cleaning. With that in mind, a new cleaning method is being developed to supplant these traditional methods. Preliminary research into a plasma-based method to clean organic contaminants from lithographic materials constructed an experimental device that demonstrated the removal of both polystyrene latex nanoparticles (representing hydrocarbon contamination) in the range of 30 nm to 500 nm, as well as the removal of 30 nm carbon film layers on silicon wafers. This research, called the Plasma-Assisted Cleaning by Metastable Atomic Neutralization (PACMAN) process is being developed with semiconductor manufacturing cleaning in mind. A model of the helium metastable density within the processing chamber has been developed in addition to

  15. Adsorption of Compounds that Mimic Urban Stormwater Dissolved Organic Nitrogen.

    PubMed

    Mohtadi, Mehrdad; James, Bruce R; Davis, Allen P

    2017-02-01

      Stormwater runoff carrying nitrogen can accelerate eutrophication. Bioretention facilities are among low impact development systems which are commonly used to manage urban stormwater quality and quantity. They are, however, not designed to remove dissolved organic nitrogen (DON) and may become a net DON exporter. Adsorption of seven organic nitrogenous compounds onto several adsorbents was examined. Batch adsorption study revealed that coal activated carbon (AC) exhibited the best performance in adsorption of the selected organic nitrogenous compounds. The highest adsorption capacity of coal AC was 0.4 mg N/g for pyrrole at an equilibrium concentration of 0.02 mg N/L, while adsorption was not detectable for urea at the same equilibrium concentration. The fastest compound to reach equilibrium adsorption capacity onto the coal AC was pyrrole (1 hour). The adsorption capacity of the coal AC for pyrrole and N-acetyl-d-glucosamine and 1-hour contact time is recommended for designing bioretention systems targeting organic nitrogenous compounds.

  16. Organic photosensitive devices using subphthalocyanine compounds

    DOEpatents

    Rand, Barry [Princeton, NJ; Forrest, Stephen R [Ann Arbor, MI; Mutolo, Kristin L [Hollywood, CA; Mayo, Elizabeth [Alhambra, CA; Thompson, Mark E [Anaheim Hills, CA

    2011-07-05

    An organic photosensitive optoelectronic device, having a donor-acceptor heterojunction of a donor-like material and an acceptor-like material and methods of making such devices is provided. At least one of the donor-like material and the acceptor-like material includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound; and/or the device optionally has at least one of a blocking layer or a charge transport layer, where the blocking layer and/or the charge transport layer includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound.

  17. Toxic organic compounds from energy production

    SciTech Connect

    Hites, R.A.

    1990-11-29

    The general theme of this program has been the identification of potentially toxic organic compounds associated with various combustion effluents, following the fates of these compounds in the environment, and improving the analytical methodology for making these measurements. Current work focuses on the fate of combustion-produced polychlorinated dioxins and dibenzofurans. Studies have included: wet and dry deposition; photodegradation; sources of pollutants; liquid chromatography; and measurement of human exposure to environmental contaminants. Of particular was the correlation of lead to dioxins and dibenzofurans. 10 tabs., 33 refs.

  18. Climate impacts of biogenic organic compounds

    NASA Astrophysics Data System (ADS)

    Sengupta, Kamalika; Gordon, Hamish; Almeida, Joao; Rap, Alex; Scott, Catherine; Pringle, Kirsty; Carslaw, Ken

    2016-04-01

    Currently the most uncertain driver of climate change, impact of anthropogenic aerosols on earth's radiative balance depends significantly on estimates of cloud condensation nuclei (CCN), representation of the pre-industrial atmosphere among others. Nearly 90% of aerosols in the tropics are organic in nature of which a major part comes from biogenic sources. About 45% of the CCN in the atmosphere are formed in-situ via nucleation. Understanding the role of biogenic organic compounds in particle formation and their subsequent growth is hence imperative in order to quantify the climate impact of aerosols. The CLOUD experiment at CERN, which measures particle formation and growth rates in a uniquely clean chamber under atmospherically relevant conditions, found evidence of a nucleation mechanism involving only biogenic organic compounds. This mechanism significantly changes our pre-industrial estimates. The experimental results have been parameterized and included in a global aerosol microphysics model, GLOMAP, to quantify the impact of pure biogenic nucleation on CCN formation and their climatic impact. Further the treatment of secondary organic compounds in GLOMAP has been improved and the sensitivity of our estimates of radiative forcing to the same has been evaluated.

  19. Toxic organic compounds from energy production

    SciTech Connect

    Hites, R.A.

    1991-09-20

    The US Department of Energy's Office of Health and Environmental Research (OHER) has supported work in our laboratory since 1977. The general theme of this program has been the identification of potentially toxic organic compounds associated with various combustion effluents, following the fates of these compounds in the environment, and improving the analytical methodology for making these measurements. The projects currently investigation include: an improved sampler for semi-volatile compounds in the atmosphere; the wet and dry deposition of dioxins and furans from the atmosphere; the photodegradation and mobile sources of dioxins and furans; and the bioaccumulation of PAH by tree bark. These projects are all responsive to OHER's interest in the pathways and mechanisms by which energy-related agents move through and are modified by the atmosphere''. The projects on gas chromatographic and liquid chromatographic tandem mass spectrometry are both responsive to OHER's interest in new and more sensitive technologies for chemical measurements''. 35 refs., 9 figs.

  20. Predicting the octanol solubility of organic compounds.

    PubMed

    Admire, Brittany; Yalkowsky, Samuel H

    2013-07-01

    The molar octanol solubility of an organic nonelectrolytes can be reasonably predicted solely from its melting point provided that its liquid (or a hypothetical super-cooled liquid) form is miscible with octanol. The aim of this work is to develop criteria to determine if the real or hypothetical liquid form of a given compound will be miscible with octanol based on its molar volume and solubility parameter. Fortunately, most organic compounds (including most drugs) conform to the criteria for complete liquid miscibility, and therefore have solubilities that are proportional to their melting points. The results show that more than 95% of the octanol solubilities studied are predicted with an error of less than 1 logarithmic unit.

  1. Organic compounds in star forming regions.

    PubMed

    Kochina, O; Wiebe, D

    2014-09-01

    The influence of complex dust composition on the general chemical evolution of a prestellar core and the content of complex organic compounds is studied. It is shown that various component groups respond differently to the presence of a small dust population. At early stages the difference is determined primarily by changes in the balance of photo processes due to effective absorption of ultraviolet photons by small dust grains of the second population and collisional reactions with dust particles. At later stages differences are also caused by the growing dominance of additional reaction channels related to surface organic synthesis.

  2. Organic Compounds in Star Forming Regions

    NASA Astrophysics Data System (ADS)

    Kochina, O.; Wiebe, D.

    2014-09-01

    The influence of complex dust composition on the general chemical evolution of a prestellar core and the content of complex organic compounds is studied. It is shown that various component groups respond differently to the presence of a small dust population. At early stages the difference is determined primarily by changes in the balance of photo processes due to effective absorption of ultraviolet photons by small dust grains of the second population and collisional reactions with dust particles. At later stages differences are also caused by the growing dominance of additional reaction channels related to surface organic synthesis.

  3. Metabolic Reactions among Organic Sulfur Compounds

    NASA Technical Reports Server (NTRS)

    Schulte, M.; Rogers, K.

    2005-01-01

    Sulfur is central to the metabolisms of many organisms that inhabit extreme environments. Numerous authors have addressed the energy available from a variety of inorganic sulfur redox pairs. Less attention has been paid, however, to the energy required or gained from metabolic reactions among organic sulfur compounds. Work in this area has focused on the oxidation of alkyl sulfide or disulfide to thiol and formaldehyde, e.g. (CH3)2S + H2O yields CH3SH + HCHO + H2, eventually resulting in the formation of CO2 and SO4(-2). It is also found that reactions among thiols and disulfides may help control redox disequilibria between the cytoplasm and the periplasm. Building on our earlier efforts for thiols, we have compiled and estimated thermodynamic properties for alkyl sulfides. We are investigating metabolic reactions among various sulfur compounds in a variety of extreme environments, ranging from sea floor hydrothermal systems to organic-rich sludge. Using thermodynamic data and the revised HKF equation of state, along with constraints imposed by the geochemical environments sulfur-metabolizing organisms inhabit, we are able to calculate the amount of energy available to these organisms.

  4. Metabolic Reactions among Organic Sulfur Compounds

    NASA Technical Reports Server (NTRS)

    Schulte, M.; Rogers, K.

    2005-01-01

    Sulfur is central to the metabolisms of many organisms that inhabit extreme environments. Numerous authors have addressed the energy available from a variety of inorganic sulfur redox pairs. Less attention has been paid, however, to the energy required or gained from metabolic reactions among organic sulfur compounds. Work in this area has focused on the oxidation of alkyl sulfide or disulfide to thiol and formaldehyde, e.g. (CH3)2S + H2O yields CH3SH + HCHO + H2, eventually resulting in the formation of CO2 and SO4(-2). It is also found that reactions among thiols and disulfides may help control redox disequilibria between the cytoplasm and the periplasm. Building on our earlier efforts for thiols, we have compiled and estimated thermodynamic properties for alkyl sulfides. We are investigating metabolic reactions among various sulfur compounds in a variety of extreme environments, ranging from sea floor hydrothermal systems to organic-rich sludge. Using thermodynamic data and the revised HKF equation of state, along with constraints imposed by the geochemical environments sulfur-metabolizing organisms inhabit, we are able to calculate the amount of energy available to these organisms.

  5. The removal of endocrine disrupting compounds, pharmaceutically activated compounds and cyanobacterial toxins during drinking water preparation using activated carbon--a review.

    PubMed

    Delgado, Luis F; Charles, Philippe; Glucina, Karl; Morlay, Catherine

    2012-10-01

    This paper provides a review of recent scientific research on the removal by activated carbon (AC) in drinking water (DW) treatment of 1) two classes of currently unregulated trace level contaminants with potential chronic toxicity-pharmaceutically activate compounds (PhACs) and endocrine disrupting compounds (EDCs); 2) cyanobacterial toxins (CyBTs), which are a group of highly toxic and regulated compounds (as microcystin-LR); and 3) the above mentioned compounds by the hybrid system powdered AC/membrane filtration. The influence of solute and AC properties, as well as the competitive effect from background natural organic matter on the adsorption of such trace contaminants, are also considered. In addition, a number of adsorption isotherm parameters reported for PhACs, EDCs and CyBTs are presented herein. AC adsorption has proven to be an effective removal process for such trace contaminants without generating transformation products. This process appears to be a crucial step in order to minimize PhACs, EDCs and CyBTs in finished DW, hence calling for further studies on AC adsorption removal of these compounds. Finally, a priority chart of PhACs and EDCs warranting further study for the removal by AC adsorption is proposed based on the compounds' structural characteristics and their low removal by AC compared to the other compounds.

  6. Methods for determination of toxic organic compounds in air

    SciTech Connect

    Winberry, W.T. Jr.

    1990-01-01

    This paper provides environmental regulatory agencies, industry, and other interested parties with specific, standardized sampling and analysis procedures for toxic organic compounds in air. Compounds include Volatile Organic Compounds, Organochlorine Pesticides and PCBs, Aldehydes and Ketones, Phosgene, N-Nitrosodimethylamine, Phenol and Methylphenols (Cresols), Polychlorinated Dibenzo-p-Dioxins (PCDDs), Formaldehyde, Non-Methane Organic Compounds (NMOCs) and Polynuclear Aromatic Hydrocarbons (PAHs).

  7. Removal of pathogenic bacterial biofilms by combinations of oxidizing compounds.

    PubMed

    Olmedo, Gabriela María; Grillo-Puertas, Mariana; Cerioni, Luciana; Rapisarda, Viviana Andrea; Volentini, Sabrina Inés

    2015-05-01

    Bacterial biofilms are commonly formed on medical devices and food processing surfaces. The antimicrobials used have limited efficacy against the biofilms; therefore, new strategies to prevent and remove these structures are needed. Here, the effectiveness of brief oxidative treatments, based on the combination of sodium hypochlorite (NaClO) and hydrogen peroxide (H2O2) in the presence of copper sulfate (CuSO4), were evaluated against bacterial laboratory strains and clinical isolates, both in planktonic and biofilm states. Simultaneous application of oxidants synergistically inactivated planktonic cells and prevented biofilm formation of laboratory Escherichia coli, Salmonella enterica serovar Typhimurium, Klebsiella pneumoniae, and Staphylococcus aureus strains, as well as clinical isolates of Salmonella enterica subsp. enterica, Klebsiella oxytoca, and uropathogenic E. coli. In addition, preformed biofilms of E. coli C, Salmonella Typhimurium, K. pneumoniae, and Salmonella enterica exposed to treatments were removed by applying 12 mg/L NaClO, 0.1 mmol/L CuSO4, and 350 mmol/L H2O2 for 5 min. Klebsiella oxytoca and Staphylococcus aureus required a 5-fold increase in NaClO concentration, and the E. coli clinical isolate remained unremovable unless treatments were applied on biofilms formed within 24 h instead of 48 h. The application of treatments that last a few minutes using oxidizing compounds at low concentrations represents an interesting disinfection strategy against pathogens associated with medical and industrial settings.

  8. Removal of phenolic compounds in water by ultrafiltration membrane treatments.

    PubMed

    Acero, Juan L; Benítez, F Javier; Leal, Ana I; Real, Francisco J

    2005-01-01

    The ultrafiltration (UF) of aqueous solutions containing mixtures of three phenolic compounds (gallic acid, acetovanillone, and esculetin) was studied in a tangential UF laboratory system. These substances were selected as model pollutants present in the tannic fraction of the cork processing wastewaters. The two membranes used were a polyethersulfone membrane (Biomax5K) and a regenerated cellulose membrane (Ultracel5K), both with a molecular weight cut-off (MWCO) of 5000 Da. Previous experiments for the characterization of the membranes led to values for the water hydraulic permeability of 70.3 and 18.1 L/h x m2 x bar for the Biomax5K and Ultracel5K membranes, respectively. During the UF experiments, the permeate flow rate remained almost constant with processing time and the evolution of the pollutants concentrations varied depending on the nature of the membranes and the substances. The influence of the main operating variables (tansmembrane pressure and feed flow rate) on the permeate flux was established, and values for the apparent and intrinsic rejection coefficients were evaluated. Cork processing wastewater UF experiments were also conducted under similar operating conditions to those applied to the ultrapure water solutions. Removals of chemical oxygen demand, aromatic and tannic contents, and color were determined in these experiments, and the elimination of the three model compounds in the wastewater was also followed, with the evaluation of their apparent rejection coefficients.

  9. Formation of highly oxidized multifunctional organic compounds from anthropogenic volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Molteni, Ugo; Baltensperger, Urs; Bianchi, Federico; Dommen, Josef; El Haddad, Imad; Frege, Carla; Klein, Felix; Rossi, Michel

    2016-04-01

    Recent studies have shown that highly oxidized multifunctional organic compounds (HOMs) from biogenic volatile organic compounds are important for new particle formation and early particle growth (e.g., Ehn et al., 2014). The formation mechanism has extensively been studied for biogenic precursors like alpha-pinene and was shown to proceed through an initial reaction with either OH radicals or ozone followed by radical propagation in a mechanism that involves O2 attack and hydrogen abstraction (Crounse et al., 2013). While the same processes can be expected for anthropogenic volatile organic compounds (AVOC), few studies have investigated these so far. Here we present the formation of HOMs from a variety of aromatic compounds after reaction with OH. All the compounds analyzed show HOM formation. AVOC could therefore play an important role in new particle formation events that have been detected in urban areas. References Crounse, J.D. et al., Autoxidation of organic compounds in the atmosphere. J. Phys.Chem. Lett. 4, 3513-3520 (2013). Ehn, M., et al. A large source of low-volatility secondary organic aerosol, Nature 506, 476-479 (2014).

  10. Self assembly properties of primitive organic compounds

    NASA Technical Reports Server (NTRS)

    Deamer, D. W.

    1991-01-01

    A central event in the origin of life was the self-assembly of amphiphilic, lipid-like compounds into closed microenvironments. If a primitive macromolecular replicating system could be encapsulated within a vesicular membrane, the components of the system would share the same microenvironment, and the result would be a step toward true cellular function. The goal of our research has been to determine what amphiphilic molecules might plausibly have been available on the early Earth to participate in the formation of such boundary structures. To this end, we have investigated primitive organic mixtures present in carbonaceous meteorites such as the Murchison meteorite, which contains 1-2 percent of its mass in the form of organic carbon compounds. It is likely that such compounds contributed to the inventory of organic carbon on the prebiotic earth, and were available to participate in chemical evolution leading to the emergence of the first cellular life forms. We found that Murchison components extracted into non-polar solvent systems are surface active, a clear indication of amphiphilic character. One acidic fraction self-assembles into vesicular membranes that provide permeability barriers to polar solutes. Other evidence indicates that the membranes are bimolecular layers similar to those formed by contemporary membrane lipids. We conclude that bilayer membrane formation by primitive amphiphiles on the early Earth is feasible. However, only a minor fraction of acidic amphiphiles assembles into bilayers, and the resulting membranes require narrowly defined conditions of pH and ionic composition to be stable. It seems unlikely, therefore, that meteoritic infall was a direct source of membrane amphiphiles. Instead, the hydrocarbon components and their derivatives more probably would provide an organic stock available for chemical evolution. Our current research is directed at possible reactions which would generate substantial quantities of membranogenic

  11. The Atmospheric Fate of Organic Nitrogen Compounds

    NASA Astrophysics Data System (ADS)

    Borduas, Nadine

    Organic nitrogen compounds are present in our atmosphere from biogenic and anthropogenic sources and have impacts on air quality and climate. Due to recent advances in instrumentation, these compounds are being detected in the gas and particle phases, raising questions as to their source, processing and sinks in the environment. With their recently identified role as contributors to aerosol formation and growth, their novel large scale use as solvents in carbon capture and storage (CCS) technology and their emissions from cigarette smoke, it is now important to address the gaps in our understanding of the fate of organic nitrogen. Experimentally and theoretically, I studied the chemical atmospheric fate of specific organic nitrogen compounds in the amine, amide and isocyanate families, yielding information that can be used in chemical transport models to assess the fate of this emerging class of atmospheric molecules. I performed kinetic laboratory studies in a smog chamber to measure the room temperature rate coefficient for reaction with the hydroxyl radical of monoethanolamine, nicotine, and five different amides. I employed online-mass spectrometry techniques to quantify the oxidation products. I found that amines react quickly with OH radicals with lifetimes of a few hours under sunlit conditions, producing amides as oxidation products. My studies on amides revealed that they have much longer lifetimes in the atmosphere, ranging from a few hours to a week. Photo-oxidation of amides produces isocyanates and I investigated these mechanisms in detail using ab initio calculations. Furthermore, I experimentally measured isocyanic acid's Henry's Law constant as well as its hydrolysis rate constants to better understand its sinks in the atmosphere. Finally, I re-examined the structure-activity relationship (SAR) of organic nitrogen molecules for improved model parameterizations.

  12. Temperature sensitivity of organic compound destruction in SCWO process.

    PubMed

    Tan, Yaqin; Shen, Zhemin; Guo, Weimin; Ouyang, Chuang; Jia, Jinping; Jiang, Weili; Zhou, Haiyun

    2014-03-01

    To study the temperature sensitivity of the destruction of organic compounds in supercritical water oxidation process (SCWO), oxidation effects of twelve chemicals in supercritical water were investigated. The SCWO reaction rates of different compounds improved to varying degrees with the increase of temperature, so the highest slope of the temperature-effect curve (imax) was defined as the maximum ratio of removal ratio to working temperature. It is an important index to stand for the temperature sensitivity effect in SCWO. It was proven that the higher imax is, the more significant the effect of temperature on the SCWO effect is. Since the high-temperature area of SCWO equipment is subject to considerable damage from fatigue, the temperature is of great significance in SCWO equipment operation. Generally, most compounds (imax > 0.25) can be completely oxidized when the reactor temperature reaches 500°C. However, some compounds (imax > 0.25) need a higher temperature for complete oxidation, up to 560°C. To analyze the correlation coefficients between imax and various molecular descriptors, a quantum chemical method was used in this study. The structures of the twelve organic compounds were optimized by the Density Functional Theory B3LYP/6-311G method, as well as their quantum properties. It was shown that six molecular descriptors were negatively correlated to imax while other three descriptors were positively correlated to imax. Among them, dipole moment had the greatest effect on the oxidation thermodynamics of the twelve organic compounds. Once a correlation between molecular descriptors and imax is established, SCWO can be run at an appropriate temperature according to molecular structure.

  13. Occurrence and removal of pharmaceutically active compounds in sewage treatment plants with different technologies

    USGS Publications Warehouse

    Ying, Guang-Guo; Kookana, Rai S.; Kolpin, Dana W.

    2009-01-01

    Occurrence of eight selected pharmaceutically active compounds (PhACs; caffeine, carbamazepine, triclosan, gemfibrozil, diclofenac, ibuprofen, ketoprofen and naproxen) were investigated in effluents from fifteen sewage treatment plants (STPs) across South Australia. In addition, a detailed investigation into the removal of these compounds was also carried out in four STPs with different technologies (Plant A: conventional activated sludge; plant B: two oxidation ditches; plant C: three bioreactors; and plant D: ten lagoons in series). The concentrations of these compounds in the effluents from the fifteen STPs showed substantial variations among the STPs, with their median concentrations ranging from 26 ng/L for caffeine to 710 ng/L for carbamazepine. Risk assessment based on the "worst case scenario" of the monitoring data from the present study suggested potential toxic risks to aquatic organisms posed by carbamazepine, triclosan and diclofenac associated with such effluent discharge. With the exception of carbamazepine and gemfibrozil, significant concentration decreases between influent and effluent were observed in the four STPs studied in more detail. Biodegradation was found to be the main mechanism for removing concentrations from the liquid waste stream for the PhACs within the four STPs, while adsorption onto sludge appeared to be a minor process for all target PhACs except for triclosan. Some compounds (e.g. gemfibrozil) exhibited variable removal efficiencies within the four STPs. Plant D (10 lagoons in series) was least efficient in the removal of the target PhACs; significant biodegradation of these compounds only occurred from the sixth or seventh lagoon.

  14. Reverse osmosis processing of organic model compounds and fermentation broths.

    PubMed

    Diltz, Robert A; Marolla, Theodore V; Henley, Michael V; Li, Lixiong

    2007-02-01

    Post-treatment of an anaerobic fermentation broth was evaluated using a 150 gal/day, single cartridge prototype reverse osmosis (RO) system. Baseline tests were conducted at 25 degrees C using six organic model compounds representing key species found in the fermentation broth: ethanol, butanol, acetic acid, oxalic acid, lactic acid, and butyric acid. Correlations of the rejection and recovery efficiencies for these organic species, individually and in simulated mixtures, were obtained as a function of feed pressure with and without recirculation of the retentate. The actual fermentation broth obtained from a continuous-flow biohydrogen process was treated by the RO system under the operating conditions similar to those used in the baseline tests, resulting in greater than 95% removal of total organic carbon. These results are encouraging and useful for further studies on the feasibility of incorporating the RO technology into an integrated and field deployable wastewater management and water recovery system.

  15. Chemical coagulation-based processes for trace organic contaminant removal: current state and future potential.

    PubMed

    Alexander, Jonathan T; Hai, Faisal I; Al-Aboud, Turki M

    2012-11-30

    Trace organic contaminants have become an increasing cause of concern for governments and water authorities as they attempt to respond to the potential challenges posed by climate change by implementing sustainable water cycle management practices. The augmentation of potable water supplies through indirect potable water reuse is one such method currently being employed. Given the uncertainty surrounding the potential human health impacts of prolonged ingestion of trace organic contaminants, it is vital that effective and sustainable treatment methods are utilized. The purpose of this article is to provide a comprehensive literature review of the performance of the chemical coagulation process in removing trace organic contaminants from water. This study evaluated the removal data collated from recent research relating to various trace organic contaminants during the coagulation process. It was observed that there is limited research data relating to the removal of trace organic contaminants using coagulation. The findings of this study suggest that there is a gap in the current research investigating the potential of new types of coagulants and exploring coagulation-based hybrid processes to remove trace organic contaminants from water. The data analysed in this study regarding removal efficiency suggests that, even for the significantly hydrophobic compounds, hydrophobicity is not the sole factor governing removal of trace organic contaminants by coagulation. This has important implications in that the usual practice of screening coagulants based on turbidity (suspended solid) removal proves inadequate in the case of trace organic contaminant removal. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Biogenic volatile organic compounds - small is beautiful

    NASA Astrophysics Data System (ADS)

    Owen, S. M.; Asensio, D.; Li, Q.; Penuelas, J.

    2012-12-01

    While canopy and regional scale flux measurements of biogenic volatile organic compounds (bVOCs) are essential to obtain an integrated picture of total compound reaching the atmosphere, many fascinating and important emission details are waiting to be discovered at smaller scales, in different ecological and functional compartments. We concentrate on bVOCs below ground to <2m above ground level. Emissions at leaf scale are well documented and widely presented, and are not discussed here. Instead we describe some details of recent research on rhizosphere bVOCs, and bVOCs associated with pollination of flowers. Although bVOC emissions from soil surfaces are small, bVOCs are exuded by roots of some plant species, and can be extracted from decaying litter. Naturally occurring monoterpenes in the rhizosphere provide a specialised carbon source for micro-organisms, helping to define the micro-organism community structure, and impacting on nutrient cycles which are partly controlled by microorganisms. Naturally occurring monoterpenes in the soil system could also affect the aboveground structure of ecosystems because of their role in plant defence strategies and as mediating chemicals in allelopathy. A gradient of monoterpene concentration was found in soil around Pinus sylvestris and Pinus halepensis, decreasing with distance from the tree. Some compounds (α-pinene, sabinene, humulene and caryophyllene) in mineral soil were linearly correlated with the total amount of each compound in the overlying litter, indicating that litter might be the dominant source of these compounds. However, α-pinene did not fall within the correlation, indicating a source other than litter, probably root exudates. We also show that rhizosphere bVOCs can be a carbon source for soil microbes. In a horizontal gradient from Populus tremula trees, microbes closest to the tree trunk were better enzymatically equipped to metabolise labeled monoterpene substrate. Monoterpenes can also increase the

  17. Volatile Organic Compounds in the Global Atmosphere

    NASA Astrophysics Data System (ADS)

    Helmig, D.; Bottenheim, J.; Galbally, I. E.; Lewis, A.; Milton, M. J. T.; Penkett, S.; Plass-Duelmer, C.; Reimann, S.; Tans, P.; Thiel, S.

    2009-12-01

    Volatile organic compounds (VOCs) include saturated, unsaturated, and other substituted hydrocarbons. VOCs play an important role in the chemistry of the atmosphere by influencing ozone and hydroxyl radical (OH) concentrations and the conversion rates of nitrogen oxides (NO x ). Elevated levels of VOCs and NO x have led to an approximate doubling of ozone in the lower troposphere over the past couple of centuries, making tropospheric ozone the third most important anthropogenic greenhouse gas after carbon dioxide (CO2) and methane. Because of ozone's strong oxidizing properties, increases in tropospheric ozone are a concern for living systems on Earth. Ozone stresses and damages vegetation, resulting in a reduction of terrestrial CO2 sequestration. VOCs also serve as a source of atmospheric secondary organic aerosol (SOA), which influences the solar radiation budget and cloud droplet nucleation. Through these complex interactions, VOCs play an important role in air quality and climate.

  18. Volatile Organic Compound Emissions from Humans Indoors.

    PubMed

    Tang, Xiaochen; Misztal, Pawel K; Nazaroff, William W; Goldstein, Allen H

    2016-12-06

    Research on the sources of indoor airborne chemicals has traditionally focused on outdoor air, building materials, furnishings, and activities such as smoking, cooking, and cleaning. Relatively little research has examined the direct role of occupant emissions, even though this source clearly contributes to indoor volatile organic compounds (VOCs) and influences indoor chemistry. In this work, we quantify occupant-related gaseous VOC emissions in a university classroom using a proton-transfer-reaction time-of-flight mass spectrometer. Time-resolved concentrations of VOCs in room air and supply air were measured continuously during occupied and unoccupied periods. The emission factor for each human-emitted VOC was determined by dividing the occupant-associated source rate by the corresponding occupancy. Among the most abundant species detected were compounds associated with personal care products. Also prominent were human metabolic emissions, such as isoprene, methanol, acetone, and acetic acid. Additional sources included human skin oil oxidation by ozone, producing compounds such as 4-oxopentanal (4-OPA) and 6-methyl-5-hepten-2-one (6-MHO). By mass, human-emitted VOCs were the dominant source (57%) during occupied periods in a well-ventilated classroom, with ventilation supply air the second most important (35%), and indoor nonoccupant emissions the least (8%). The total occupant-associated VOC emission factor was 6.3 mg h(-1) per person.

  19. Palladium catalyzed hydrogenation of bio-oils and organic compounds

    DOEpatents

    Elliott, Douglas C [Kennewick, WA; Hu, Jianli [Richland, WA; Hart,; Todd, R [Kennewick, WA; Neuenschwander, Gary G [Burbank, WA

    2011-06-07

    The invention provides palladium-catalyzed hydrogenations of bio-oils and certain organic compounds. Experimental results have shown unexpected and superior results for palladium-catalyzed hydrogenations of organic compounds typically found in bio-oils.

  20. Palladium catalyzed hydrogenation of bio-oils and organic compounds

    DOEpatents

    Elliott, Douglas C.; Hu, Jianli; Hart, Todd R.; Neuenschwander, Gary G.

    2008-09-16

    The invention provides palladium-catalyzed hydrogenations of bio-oils and certain organic compounds. Experimental results have shown unexpected and superior results for palladium-catalyzed hydrogenations of organic compounds typically found in bio-oils.

  1. A method of isolating organic compounds present in water

    NASA Technical Reports Server (NTRS)

    Calder, G. V.; Fritz, J.; Junk, G. A.

    1972-01-01

    Water sample is passed through a column containing macroreticular resin, which absorbs only nonionic organic compounds. These compounds are selectively separated using aqueous eluents of varying pH, or completely exuded with small amount of an organic eluent.

  2. Volatile Organic Compound Analysis in Istanbul

    NASA Astrophysics Data System (ADS)

    Ćapraz, Ö.; Deniz, A.; Öztürk, A.; Incecik, S.; Toros, H.; Coşkun, M.

    2012-04-01

    Volatile Organic Compound Analysis in Istanbul Ö. Çapraz1, A. Deniz1,3, A. Ozturk2, S. Incecik1, H. Toros1 and, M. Coskun1 (1) Istanbul Technical University, Faculty of Aeronautics and Astronautics, Department of Meteorology, 34469, Maslak, Istanbul, Turkey. (2) Istanbul Technical University, Faculty of Chemical and Metallurgical, Chemical Engineering, 34469, Maslak, Istanbul, Turkey. (3) Marmara Clean Air Center, Ministry of Environment and Urbanization, Nişantaşı, 34365, İstanbul, Turkey. One of the major problems of megacities is air pollution. Therefore, investigations of air quality are increasing and supported by many institutions in recent years. Air pollution in Istanbul contains many components that originate from a wide range of industrial, heating, motor vehicle, and natural emissions sources. VOC, originating mainly from automobile exhaust, secondhand smoke and building materials, are one of these compounds containing some thousands of chemicals. In spite of the risks to human health, relatively little is known about the levels of VOC in Istanbul. In this study, ambient air quality measurements of 32 VOCs including hydrocarbons, halogenated hydrocarbons and carbonyls were conducted in Kağıthane (Golden Horn) region in Istanbul during the winter season of 2011 in order to develop the necessary scientific framework for the subsequent developments. Kağıthane creek valley is the source part of the Golden Horn and one of the most polluted locations in Istanbul due to its topographical form and pollutant sources in the region. In this valley, horizontal and vertical atmospheric motions are very weak. The target compounds most commonly found were benzene, toluene, xylene and ethyl benzene. Concentrations of total hydrocarbons ranged between 1.0 and 10.0 parts per billion, by volume (ppbv). Ambient air levels of halogenated hydrocarbons appeared to exhibit unique spatial variations and no single factor seemed to explain trends for this group of

  3. Removal of enzymatic and fermentation inhibitory compounds from biomass slurries for enhanced biorefinery process efficiencies.

    PubMed

    Gurram, Raghu N; Datta, Saurav; Lin, Yupo J; Snyder, Seth W; Menkhaus, Todd J

    2011-09-01

    Within the biorefinery paradigm, many non-monomeric sugar compounds have been shown to be inhibitory to enzymes and microbial organisms that are used for hydrolysis and fermentation. Here, two novel separation technologies, polyelectrolyte polymer adsorption and resin-wafer electrodeionization (RW-EDI), have been evaluated to detoxify a dilute acid pretreated biomass slurry. Results showed that detoxification of a dilute acid pretreated ponderosa pine slurry by sequential polyelectrolyte and RW-EDI treatments was very promising, with significant removal of acetic acid, 5-hydroxymethyl furfural, and furfural (up to 77%, 60%, and 74% removed, respectively) along with >97% removal of sulfuric acid. Removal of these compounds increased the cellulose conversion to 94% and elevated the hydrolysis rate to 0.69 g glucose/L/h. When using Saccharomyces cerevisiae D(5)A for fermentation of detoxified slurry, the process achieved 99% of the maximum theoretical ethanol yield and an ethanol production rate nearly five-times faster than untreated slurry. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Nitrate radicals and biogenic volatile organic compounds ...

    EPA Pesticide Factsheets

    Oxidation of biogenic volatile organic compounds (BVOC) by the nitrate radical (NO3) represents one of the important interactions between anthropogenic emissions related to combustion and natural emissions from the biosphere. This interaction has been recognized for more than 3 decades, during which time a large body of research has emerged from laboratory, field, and modeling studies. NO3-BVOC reactions influence air quality, climate and visibility through regional and global budgets for reactive nitrogen (particularly organic nitrates), ozone, and organic aerosol. Despite its long history of research and the significance of this topic in atmospheric chemistry, a number of important uncertainties remain. These include an incomplete understanding of the rates, mechanisms, and organic aerosol yields for NO3-BVOC reactions, lack of constraints on the role of heterogeneous oxidative processes associated with the NO3 radical, the difficulty of characterizing the spatial distributions of BVOC and NO3 within the poorly mixed nocturnal atmosphere, and the challenge of constructing appropriate boundary layer schemes and non-photochemical mechanisms for use in state-of-the-art chemical transport and chemistry–climate models. This review is the result of a workshop of the same title held at the Georgia Institute of Technology in June 2015. The first half of the review summarizes the current literature on NO3-BVOC chemistry, with a particular focus on recent advances in

  5. High organic sulfur removal performance of a cobalt based metal-organic framework.

    PubMed

    Bagheri, Minoo; Masoomi, Mohammad Yaser; Morsali, Ali

    2017-06-05

    Synthesis of a new porous cobalt based metal-organic framework, [Co6(oba)6(CH3O)4(O)2]n·3DMF (TMU-11) has been carried out to introduce a new and highly efficient adsorbent of dibenzothiophene (DBT). This compound has been synthesized by solvothermal method using a nonlinear dicarboxylate ligand and characterized by single-crystal X-ray crystallography. To study the adsorption properties of the synthesized compound, TMU-11, for DBT removal, various factors, such as amount of adsorbent, contact time and temperature were examined. On the basis of the results, maximum efficiency and reusability in DBT removal occur under the mild reaction conditions. Furthermore, the DBT removal follows the pseudo-second order reaction kinetic. The maximum adsorption value is 825mg/g. The selectivity test of DBT over naphthalene (NA) clearly shows that π-π interactions between organic linkers of TMU-11 and the aromatic ring of DBT are not responsible for the adsorption desulfurization (ADS) process and the main part of adsorption takes place on unsaturated site around Co centres. Our findings may provide some insight into the preparation of the adsorbent with superior performance in practical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. A new material for selective removal of nitrogen compounds from gasoils towards more efficient HDS processes.

    PubMed

    Macaud, Mathieu; Schulz, Emmanuelle; Vrinat, Michel; Lemaire, Marc

    2002-10-21

    A selective removal of nitrogen compounds from gasoils is proposed, using a recyclable sorbent capable of forming charge-transfer complexes; the selective elimination of nitrogen compounds strongly improves the hydrodesulfurization (HDS) of denitrogenated feed.

  7. Determination of biological removal of recalcitrant organic contaminants in coal gasification waste water.

    PubMed

    Ji, Qinhong; Tabassum, Salma; Yu, Guangxin; Chu, Chunfeng; Zhang, Zhenjia

    2015-01-01

    Coal gasification waste water treatment needed a sustainable and affordable plan to eliminate the organic contaminants in order to lower the potential environmental and human health risk. In this paper, a laboratory-scale anaerobic-aerobic intermittent system carried out 66 operational cycles together for the treatment of coal gasification waste water and the removal capacity of each organic pollutant. Contaminants included phenols, carboxylic acids, long-chain hydrocarbons, and heterocyclic compounds, wherein the relative content of phenol is up to 57.86%. The long-term removal of 77 organic contaminants was evaluated at different hydraulic retention time (anaerobic24 h + aerobic48 h and anaerobic48 h +aerobic48 h). Contaminant removal ranged from no measurable removal to near-complete removal with effluent concentrations below the detection limit. Contaminant removals followed one of four trends: steady-state removal throughout, increasing removal to steady state (acclimation), decreasing removal, and no removal. Organic degradation and transformation in the reaction were analysed by gas chromatography/mass spectrometry technology.

  8. [Role of Anammox Bacteria in Removal of Nitrogen Compounds from Wastewater].

    PubMed

    Kallistovaa, A Yu; Dorofeev, A G; Nikolaev, Yu A; Kozlov, M N; Kevbrina, M V; Pimenov, N V

    2016-01-01

    The review deals with the unique microbial group responsible for anaerobic ammonium oxidation with nitrite (anammox), and with the role of this process in development of the biotechnology for removal of nitrogen compounds from wastewater. The history of the study of this process is briefly related. Up-to date knowledge on the intracellular organization, energy metabolism, growth stoichiometry, and physiology of anammox bacteria is described, and the main methods for cultivation of these microorganisms are characterized. Special attention is paid to the problems associated with practical application of anammox bacteria, which result from their extremely slow growth, the absence of pure cultures, and the interaction with other microbial groups.

  9. [Ru/AC catalyzed ozonation of recalcitrant organic compounds].

    PubMed

    Wang, Jian-Bing; Hou, Shao-Pei; Zhou, Yun-Rui; Zhu, Wan-Peng; He, Xu-Wen

    2009-09-15

    Ozonation and Ru/AC catalyzed ozonation of dimethyl phthalate (DMP), phenols and disinfection by-products precursors were studied. It shows that Ru/AC catalyst can obviously enhance the mineralization of organic compounds. In the degradation of DMP, TOC removal was 28.84% by ozonation alone while it was 66.13% by catalytic ozonation. In the oxidation of 23 kinds of phenols, TOC removals were 9.57%-56.08% by ozonation alone while they were 41.81%-82.32% by catalytic ozonation. Compared to ozonation alone, Ru/AC catalyzed ozonation was more effective for the reduction of disinfection by-products formation potentials in source water. The reduction of haloacetic acids formation potentials was more obvious than thichlomethane formation potentials. After the treatment by catalytic ozonation, the haloacetic acids formation potentials decreased from 144.02 microg/L to 58.50 microg/L, which was below the standard value of EPA. However ozonation alone could not make it reach the standard. The treatments of source water by BAC, O3 + BAC, O3/AC + BAC and Ru/AC + O3 + BAC were also studied. In the four processes, TOC removal was 3.80%, 20.14%, 27.45% and 48.30% respectively, COD removal was 4.37%, 27.22%, 39.91% and 50.00% respectively, UV254 removal was 8.16%, 62.24%, 67.03% and 84.95% respectively. Ru/AC + O3 + BAC process is more effective than the other processes for the removal of TOC, COD and UV254 and no ruthenium leaching observed in the solution. It is a promising process for the treatment of micro polluted source water.

  10. Measurement of volatile organic compounds in human blood.

    PubMed Central

    Ashley, D L; Bonin, M A; Cardinali, F L; McCraw, J M; Wooten, J V

    1996-01-01

    Volatile organic compounds (VOCs) are an important public health problem throughout the developed world. Many important questions remain to be addressed in assessing exposure to these compounds. Because they are ubiquitous and highly volatile, special techniques must be applied in the analytical determination of VOCs. The analytical methodology chosen to measure toxicants in biological materials must be well validated and carefully carried out; poor quality assurance can lead to invalid results that can have a direct bearing on treating exposed persons. The pharmacokinetics of VOCs show that most of the internal dose of these compounds is quickly eliminated, but there is a fraction that is only slowly removed, and these compounds may bioaccumulate. VOCs are found in the general population at the high parts-per-trillion range, but some people with much higher levels have apparently been exposed to VOC sources away from the workplace. Smoking is the most significant confounder to internal dose levels of VOCs and must be considered when evaluating suspected cases of exposure. PMID:8933028

  11. IRRADIATION METHOD OF CONVERTING ORGANIC COMPOUNDS

    DOEpatents

    Allen, A.O.; Caffrey, J.M. Jr.

    1960-10-11

    A method is given for changing the distribution of organic compounds from that produced by the irradiation of bulk alkane hydrocarbons. This method consists of depositing an alkane hydrocarbon on the surface of a substrate material and irradiating with gamma radiation at a dose rate of more than 100,000 rads. The substrate material may be a metal, metal salts, metal oxides, or carbons having a surface area in excess of 1 m/sup 2//g. The hydrocarbons are deposited in layers of from 0.1 to 10 monolayers on the surfaces of these substrates and irradiated. The product yields are found to vary from those which result from the irradiation of bulk hydrocarbons in that there is an increase in the quantity of branched hydrocarbons.

  12. Volatilization of organic compounds from streams

    USGS Publications Warehouse

    Rathburn, R.E.; Tai, D.Y.

    1982-01-01

    Mass-transfer coefficients for the volatilization of ethylene and propane were correlated with the hydraulic and geometric properties of seven streams, and predictive equations were developed. The equations were evaluated using a normalized root-mean-square error as the criterion of comparison. The two best equations were a two-variable equation containing the energy dissipated per unit mass per unit time and the average depth of flow and a three-variable equation containing the average velocity, the average depth of flow, and the slope of the stream. Procedures for adjusting the ethylene and propane coefficients for other organic compounds were evaluated. These procedures are based on molecular diffusivity, molecular diameter, or molecular weight. Because of limited data, none of these procedures have been extensively verified. Therefore, until additional data become available, it is suggested that the mass-transfer coefficient be assumed to be inversely proportional to the square root of the molecular weight.

  13. Microbiological Assay for Organic Compounds in Seawater

    PubMed Central

    Litchfield, Carol D.; Hood, Donald W.

    1965-01-01

    A method for the quantitative identification of organic compounds in seawater has been developed. When auxotrophic mutants of Serratia marinorubra were incubated at 21 to 24 C for 72 hr with constant agitation, standard bioassay reference curves were obtained. Sodium glycerophosphate (400 mg per liter), ammonium dibasic citrate (5 g per liter), and glycerol (25 ml per liter) supplied the needed nutrients for maximal growth with a limited concentration of the required metabolite. Data are presented for the microbiological assay for biotin in waters of the Gulf of Mexico and adjacent bays. The range of sensitivity for the biotin mutant A101V is 5 to 12 mμg per liter in seawater, with a growth response from 2 to 16 mμg per liter of seawater. The possible ecological and chemical significance of biotin occurrence in spring-summer off-shore water is discussed. PMID:5866037

  14. Extraction of organic compounds from solid samples

    SciTech Connect

    Junk, G.A.; Richard, J.J.

    1986-04-01

    Pyridine, benzene, cyclohexane, methylene chloride, dimethyl sulfoxide, dimethylformamide, and n-methylpyrrolidone have been compared for the extraction of polycyclic organic materials (POMs) from urban air, diesel, and stack particulate samples. Both sonic and Soxhlet techniques have been examined for both natural environmental particulates and particulates spiked with selected POMs. The extraction results vary for different polycyclic compounds adsorbed on different solid matrices, so no single solvent or extraction technique could be unambiguously recommended. However, comparative average results for 14 compounds spiked onto fly ash at 0.1, 0.25, and 1.0 ..mu..g/g showed pyridine to have 1.5 times more extraction efficiency than benzene. These and other reported results suggest that pyridine deserves more attention as an extractant for particulate samples. In separate tests, recoveries of POMs from fly ash were not improved by deactivation with aqueous solutions of ammonium hydroxide, thiocyanate and carbonate, and sodium nitrite prior to the extraction. 39 references, 5 tables.

  15. Removal of emerging organic contaminants in a poplar vegetation filter.

    PubMed

    Martínez-Hernández, V; Leal, M; Meffe, R; de Miguel, A; Alonso-Alonso, C; de Bustamante, I; Lillo, J; Martín, I; Salas, J J

    2017-08-24

    Vegetation filters (VFs), a type of land application system, are a robust technology based on natural treatment mechanisms for the removal of wastewater contaminants. Their capacity to attenuate emerging organic contaminants (EOCs) has not yet been evaluated. The present study reports the results of a 2-year EOC monitoring carried out using a poplar VF receiving wastewater primarily treated by an Imhoff tank. The compounds selected included analgesics, a β-adrenergic blocker, stimulants, an anticonvulsant, an anti-depressant, an anti-inflammatory, an antibiotic and analgesic and stimulant metabolites. EOCs were analysed in the Imhoff tank effluent, in the infiltrated water at a depth of 90cm and in the groundwater at a depth of 10m. The results demonstrated that EOC attenuation was more significant in the first 90cm than in the rest of the soil profile. The removal efficiency for all of the selected EOCs was higher than 90% with the exception of ketoprofen, which may pose a higher threat of groundwater contamination. The observed attenuation correlated with the hydrophobicity and charge state of the EOCs. The higher persistence of the metabolites 4-AAA and 4-FAA shows that progression in the degradation pathway does not always imply a mitigation of contamination. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. [Effects of nitrate on organic removal and microbial community structure in the sediments].

    PubMed

    Liu, Jin; Deng, Dai-Yong; Sun, Guo-Ping; Liu, Yong-Ding; Xu, Mei-Ying

    2013-07-01

    The strategy promoted pollutant degradation and transformation under the anaerobic circumstance by adding nitrate as an electron acceptor has been widely used in sediment bioremediation. However, few literature reports on organic removal characteristics and microbial community responses in the contaminated river sediment under the nitrate reduction condition. Methods including the polar and non-polar chemical fractionation, relative abundance detection of organic matters by GC-MS were combined and applied to investigate organic removals and PCR-DGGE analysis was used for microbial community structures in sediment incubation systems with or without calcium nitrate addition. The results indicated that the addition of calcium nitrate could significantly enhance removal efficiencies of organic pollutants. The removal efficiency of total organic carbon (TOC) and the total peak area of organic matters in GC-MS were 47.25% and 29.55% which were higher than those of the control. The effect descending order of organic pollutants was: silicon materials > alkanes > polycyclic aromatic hydrocarbons > heterocyclic compounds > olefins > benzene homologues > polar compounds > phthalates > aldehydes and ketones > alkyl esters. And removal rates of silicon materials, the persistent organic pollutants, benzene homologues and heterocyclic compounds were 46.73%, 36.25%, 23.19% and 35.92% which were higher than those of the control. The PCR-DGGE profile of bacterial 16S rDNA V3 fragments showed obviously different microbial community structures between the treatment and the control systems. Blastn analysis revealed that sequences of 10 predominant bands from DGGE profile were closely related to Proteobacteria, Actinobacteria, Clostridia, Chloroflexi, Caldiserica and uncultured bacterium. The research findings provide some helpful scientific information for promoting organic pollutant removal of river sediment by nitrate reduction.

  17. Organic compounds in meteorites and their origins

    NASA Technical Reports Server (NTRS)

    Hayatsu, R.; Anders, E.

    1981-01-01

    The current investigation represents an extensively updated version of a review conducted by Anders et al. (1973). The investigation takes into account the literature through mid-1980. It is pointed out that Type 1 carbonaceous chondrites (C1) contain 6% of their cosmic complement of carbon, mainly in the form of organic matter. Most authors now agree that this material represents primitive prebiotic matter. The principal questions remaining are what abiotic processes formed the organic matter, and to what extent these processes took place in locales other than the solar nebula, such as interstellar clouds or meteorite parent bodes. The problem is approached in three stages. It is attempted to reconstruct the physical conditions during condensation from the clues contained in the inorganic matrix of the meteorite. The condensation behavior of carbon under these conditions is determined on the basis of thermodynamic calculations. Model experiments on the condensation of carbon are performed, and the synthesized compounds are compared with those actually found in meteorites.

  18. Organic compounds in meteorites and their origins

    NASA Technical Reports Server (NTRS)

    Hayatsu, R.; Anders, E.

    1981-01-01

    The current investigation represents an extensively updated version of a review conducted by Anders et al. (1973). The investigation takes into account the literature through mid-1980. It is pointed out that Type 1 carbonaceous chondrites (C1) contain 6% of their cosmic complement of carbon, mainly in the form of organic matter. Most authors now agree that this material represents primitive prebiotic matter. The principal questions remaining are what abiotic processes formed the organic matter, and to what extent these processes took place in locales other than the solar nebula, such as interstellar clouds or meteorite parent bodes. The problem is approached in three stages. It is attempted to reconstruct the physical conditions during condensation from the clues contained in the inorganic matrix of the meteorite. The condensation behavior of carbon under these conditions is determined on the basis of thermodynamic calculations. Model experiments on the condensation of carbon are performed, and the synthesized compounds are compared with those actually found in meteorites.

  19. Occurrence and Removal of Organic Micropollutants in Landfill Leachates Treated by Electrochemical Advanced Oxidation Processes.

    PubMed

    Oturan, Nihal; van Hullebusch, Eric D; Zhang, Hui; Mazeas, Laurent; Budzinski, Hélène; Le Menach, Karyn; Oturan, Mehmet A

    2015-10-20

    In recent years, electrochemical advanced oxidation processes have been shown to be an effective alternative for the removal of refractory organic compounds from water. This study is focused on the effective removal of recalcitrant organic matter (micropollutants, humic substances, etc.) present in municipal solid waste landfill leachates. A mixture of eight landfill leachates has been studied by the electro-Fenton process using a Pt or boron-doped diamond (BDD) anode and a carbon felt cathode or by the anodic oxidation process with a BDD anode. These processes exhibit great oxidation ability due to the in situ production of hydroxyl radicals ((•)OH), a highly powerful oxidizing species. Both electrochemical processes were shown to be efficient in the removal of dissolved total organic carbon (TOC) from landfill leachates. Regarding the electro-Fenton process, the replacement of the classical anode Pt by the anode BDD allows better performance in terms of dissolved TOC removal. The occurrence and removal yield of 19 polycyclic aromatic hydrocarbons, 15 volatile organic compounds, 7 alkylphenols, 7 polychlorobiphenyls, 5 organochlorine pesticides, and 2 polybrominated diphenyl ethers in landfill leachate were also investigated. Both electrochemical processes allow one to reach a quasicomplete removal (about 98%) of these organic micropollutants.

  20. REMOVAL OF URANIUM FROM ORGANIC LIQUIDS

    DOEpatents

    Vavalides, S.P.

    1959-08-25

    A process is described for recovering small quantities of uranium from organic liquids such as hydrocarbon oils. halogen-substituted hydrocarbons, and alcohols. The organic liquid is contacted with a comminuted alkaline earth hydroxide, calcium hydroxide particularly, and the resulting uranium-bearing solid is separated from the liquid by filtration. Uranium may then be recovered from the solid by means of dissolution in nitric acid and conventional extraction with an organic solvent such as tributyl phosphate.

  1. Aerobic biodegradation of organic compounds in hydraulic fracturing fluids.

    PubMed

    Kekacs, Daniel; Drollette, Brian D; Brooker, Michael; Plata, Desiree L; Mouser, Paula J

    2015-07-01

    Little is known of the attenuation of chemical mixtures created for hydraulic fracturing within the natural environment. A synthetic hydraulic fracturing fluid was developed from disclosed industry formulas and produced for laboratory experiments using commercial additives in use by Marcellus shale field crews. The experiments employed an internationally accepted standard method (OECD 301A) to evaluate aerobic biodegradation potential of the fluid mixture by monitoring the removal of dissolved organic carbon (DOC) from an aqueous solution by activated sludge and lake water microbial consortia for two substrate concentrations and four salinities. Microbial degradation removed from 57 % to more than 90 % of added DOC within 6.5 days, with higher removal efficiency at more dilute concentrations and little difference in overall removal extent between sludge and lake microbe treatments. The alcohols isopropanol and octanol were degraded to levels below detection limits while the solvent acetone accumulated in biological treatments through time. Salinity concentrations of 40 g/L or more completely inhibited degradation during the first 6.5 days of incubation with the synthetic hydraulic fracturing fluid even though communities were pre-acclimated to salt. Initially diverse microbial communities became dominated by 16S rRNA sequences affiliated with Pseudomonas and other Pseudomonadaceae after incubation with the synthetic fracturing fluid, taxa which may be involved in acetone production. These data expand our understanding of constraints on the biodegradation potential of organic compounds in hydraulic fracturing fluids under aerobic conditions in the event that they are accidentally released to surface waters and shallow soils.

  2. Use of humic acid solution to remove organic contaminants from hydrogeologic systems

    SciTech Connect

    Abdul, A.S.; Gibson, T.L.; Rai, D.N. )

    1990-03-01

    Experiments were carried out to evaluate the effectiveness of a 29 mg/L solution of humic acid to enhance the removal of six aromatic hydrocarbons (benzene, toluene, p-xylene, ethyltoluene, sec-butylbenzene, and tetramethylbenzene) from a sandy material. None of the compounds were completely removed from the material. Nonetheless, the compounds with the highest water solubility, benzene and toluene, were removed effectively; less than 1 mass % was retained with use of either the humic acid solution or water. For the less soluble organic compounds, removal was more difficult and was enhanced by the humic acid solution compared to water. Mass percent retained with humic acid was as follows: p-xylene, 1.4% (24% less than water); 3-ethyltoluene, 6.4% (40% less); sec-butylbenzene, 39% (14% less); and tetramethylbenzene, 43% (14% less). The positive effect of humic acid on the removal of these organics may arise from the aggregation of the humic acid molecules to form membranes and/or micelles, having hydrophilic exteriors and hydrophobic interiors. Partitioning of the hydrophobic organics from the bulk solution into the hydrophobic interior of these humic acid structures can account for their enhanced removal from the sandy material.

  3. Role of fly ash in the removal of organic pollutants from wastewater

    SciTech Connect

    M. Ahmaruzzaman

    2009-03-15

    Fly ash, a relatively abundant and inexpensive material, is currently being investigated as an adsorbent for the removal of various organic pollutants from wastewater. The wastewater contains various types of phenolic compounds, such as chloro, nitro, amino, and other substituted compounds. Various types of pesticides, such as lindane, malathion, carbofuran, etc., and dyes, such as, methylene blue, crystal violet, malachite green, etc., are also present in the wastewater. These contaminants pollute the water stream. These organic pollutants, such as phenolic compounds, pesticides, and dyes, etc., can be removed very effectively using fly ash as adsorbent. This article presents a detailed review on the role of fly ash in the removal of organic pollutants from wastewater. Adsorption of various pollutants using fly ash has been reviewed. The adsorption mechanism and other influencing factors, favorable conditions, and competitive ions, etc., on the adsorption process have also been discussed in this paper. It is evident from the review that fly ash has demonstrated good removal capabilities for various organic compounds. 171 refs., 3 figs., 5 tabs.

  4. Tritium labeling of organic compounds deposited on porous structures

    DOEpatents

    Ehrenkaufer, Richard L. E.; Wolf, Alfred P.; Hembree, Wylie C.

    1979-01-01

    An improved process for labeling organic compounds with tritium is carried out by depositing the selected compound on the extensive surface of a porous structure such as a membrane filter and exposing the membrane containing the compound to tritium gas activated by the microwave discharge technique. The labeled compound is then recovered from the porous structure.

  5. Magnetically modified biochar for organic xenobiotics removal.

    PubMed

    Šafařík, Ivo; Maděrová, Zdenka; Pospíšková, Kristýna; Schmidt, Hans-Peter; Baldíková, Eva; Filip, Jan; Křížek, Michal; Malina, Ondřej; Šafaříková, Mirka

    2016-10-01

    Large amounts of biochar are produced worldwide for potential agricultural applications. However, this material can also be used as an efficient biosorbent for xenobiotics removal. In this work, biochar was magnetically modified using microwave-synthesized magnetic iron oxide particles. This new type of a magnetically responsive biocomposite material can be easily separated by means of strong permanent magnets. Magnetic biochar has been used as an inexpensive magnetic adsorbent for the removal of water-soluble dyes. Five dyes (malachite green, methyl green, Bismarck brown Y, acridine orange and Nile blue A) were used to study the adsorption process. The dyes adsorption could be usually described with the Langmuir isotherm. The maximum adsorption capacities reached the value 137 mg of dye per g of dried magnetically modified biochar for Bismarck brown Y. The adsorption processes followed the pseudo-second-order kinetic model and the thermodynamic studies indicated spontaneous and endothermic adsorption. Extremely simple magnetic modification of biochar resulted in the formation of a new, promising adsorbent suggested for selected xenobiotics removal.

  6. Electrochemical wastewater treatment: influence of the type of carbon and of nitrogen on the organic load removal.

    PubMed

    Fernandes, Annabel; Coelho, João; Ciríaco, Lurdes; Pacheco, Maria José; Lopes, Ana

    2016-12-01

    Boron-doped diamond (BDD) and Ti/Pt/PbO2 anodes were utilized to perform the electrodegradation of synthetic samples containing humic acid in the presence of different organic and inorganic carbon-containing and nitrogen-containing compounds. The influence of the chloride ion in the degradation process of the different synthetic samples was also assessed. The results showed that the anodic oxidation process can efficiently degrade recalcitrant compounds such as humic acid. The presence of carbonate in solution enhances the nitrogen removal, whereas it hinders the oxidation of the organic compounds. When organic nitrogen is present, it is converted to NH4(+), which in turn is oxidized to nitrate and to volatile nitrogen compounds. Hydroxyl radicals are more prone to oxidize the organic nitrogen than the ammonium nitrogen. The presence of chloride enhances the organic matter and nitrogen removal rates, BDD being the anode material that yields the highest removals.

  7. Aqueous adsorption and removal of organic contaminants by carbon nanotubes.

    PubMed

    Yu, Jin-Gang; Zhao, Xiu-Hui; Yang, Hua; Chen, Xiao-Hong; Yang, Qiaoqin; Yu, Lin-Yan; Jiang, Jian-Hui; Chen, Xiao-Qing

    2014-06-01

    Organic contaminants have become one of the most serious environmental problems, and the removal of organic contaminants (e.g., dyes, pesticides, and pharmaceuticals/drugs) and common industrial organic wastes (e.g., phenols and aromatic amines) from aqueous solutions is of special concern because they are recalcitrant and persistent in the environment. In recent years, carbon nanotubes (CNTs) have been gradually applied to the removal of organic contaminants from wastewater through adsorption processes. This paper reviews recent progress (145 studies published from 2010 to 2013) in the application of CNTs and their composites for the removal of toxic organic pollutants from contaminated water. The paper discusses removal efficiencies and adsorption mechanisms as well as thermodynamics and reaction kinetics. CNTs are predicted to have considerable prospects for wider application to wastewater treatment in the future.

  8. Method for removing chlorine compounds from hydrocarbon mixtures

    DOEpatents

    Janoski, Edward J.; Hollstein, Elmer J.

    1985-12-31

    A process for removing halide ions from a hydrocarbon feedstream containing halogenated hydrocarbons wherein the contaminated feedstock is contacted with a solution of a suitable oxidizing acid containing a lanthanide oxide, the acid being present in a concentration of at least about 50 weight percent for a time sufficient to remove substantially all of the halide ion from the hydrocarbon feedstock.

  9. Method for removing chlorine compounds from hydrocarbon mixtures

    DOEpatents

    Janoski, E.J.; Hollstein, E.J.

    1984-09-29

    A process for removing halide ions from a hydrocarbon feedstream containing halogenated hydrocarbons wherein the contaminated feedstock is contacted with a solution of a suitable oxidizing acid containing a lanthanide oxide, the acid being present in a concentration of at least about 50 weight percent for a time sufficient to remove substantially all of the halide ion from the hydrocarbon feedstock.

  10. Trace organic compounds in rain—II. Gas scavenging of neutral organic compounds

    NASA Astrophysics Data System (ADS)

    Ligocki, Mary P.; Leuenberger, Christian; Pankow, James F.

    Concurrent rain and air sampling was conducted for seven rain events in Portland, Oregon during February through to April of 1984. Concentration data are presented for a number of neutral organic compounds for both the rain-dissolved phase and the atmospheric gas phase. The ambient temperature averaged 8°C. Measured gas scavenging ratios ranged from 3 for tetrachloroethene to 10 5 for dibutylphthalate, and were generally 3-6 times higher than those calculated from Henry's Law constant ( H) values at 25°C taken from the literature. This discrepancy was due to the inappropriateness of applying 25°C H data at 5-10°C. Indeed, excellent agreement between the measured and predicted gas scavenging ratios was found for several polycyclic aromatic hydrocarbons for which temperature-dependent H data were available. These results demonstrate that equilibrium between rain and the atmospheric gas phase is attained for non-reactive neutral organic compounds.

  11. Biofiltration for control of volatile organic compounds (VOCS)

    SciTech Connect

    Bishop, D.F.; Govind, R.

    1995-10-01

    Air biofiltration is a promising technology for control of air emissions of biodegradable volatile organic compounds (VOCs). In conjunction with vacuum extraction of soils or air stripping of ground water, it can be used to mineralize VOCs removed from contaminated soil or groundwater. The literature describes three major biological systems for treating contaminated air bioscrubbers, biotrickling filters and biofilters. Filter media can be classified as: bioactive fine or irregular particulates, such as soil, peat, compost or mixtures of these materials; pelletized, which are randomly packed in a bed; and structured, such as monoliths with defined or variable passage size and geometry. The media can be made of sorbing and non-absorbing materials. Non-bioactive pelletized and structured media require recycled solutions of nutrients and buffer for efficient microbial activity and are thus called biotrickling filters. Extensive work has been conducted to improve biofiltration by EPA`s Risk Reduction Engineering Laboratory and the University of Cincinnati in biofilters using pelletized and structured media and improved operational approaches. Representative VOCs in these studies included compounds with a range of aqueous solubilities and octanol-water partition coefficients. The compounds include iso-pentane, toluene, methylene chloride, trichloroethylene (TCE), ethyl benzene, chlorobenzene and perchloroethylene (PCE) and alpha ({alpha}-) pinene. Comparative studies were conducted with peat/compost biofilters using isopentane and {alpha}-pinene. Control studies were also conducted to investigate adsorption/desorption of contaminants on various media using mercuric chloride solution to insure the absence of bioactivity.

  12. Remotion of organic compounds of actual industrial effluents by electron beam irradiation

    NASA Astrophysics Data System (ADS)

    Sampa, M. H. O.; Duarte, C. L.; Rela, P. R.; Somessari, E. S. R.; Silveira, C. G.; Azevedo, A. L.

    1998-06-01

    Organic compounds has been a great problem of environmental pollution, the traditional methods are not effecient on removing these compounds and most of them are deposited to ambient and stay there for long time causing problems to the environment. Ionizing radiation has been used with success to destroy organic molecules. Actual industrial effluents were irradiated using IPEN's electron beam wastewater pilot plant to study organic compounds degradation. The samples were irradiated with and without air mixture by different doses. Irradiation treatment efficiency was evaluated by the Cromatography Gas Analyses of the samples before and after irradiation. The studied organic compounds were: phenol, chloroform, tetrachloroethylene (PCE), carbon tetrachloride, trichloroethylene (TCE), 1,1-dichloroethane, dichloromethane, benzene, toluene and xilene. A degradation superior to 80% was achieved for the majority of the compounds with air addition and 2kGy delivered dose condition. For the samples that were irradiated without air addition the degradation was higher.

  13. Synthesis of magnetic metal-organic framework (MOF) for efficient removal of organic dyes from water.

    PubMed

    Zhao, Xiaoli; Liu, Shuangliu; Tang, Zhi; Niu, Hongyun; Cai, Yaqi; Meng, Wei; Wu, Fengchang; Giesy, John P

    2015-07-07

    A novel, simple and efficient strategy for fabricating a magnetic metal-organic framework (MOF) as sorbent to remove organic compounds from simulated water samples is presented and tested for removal of methylene blue (MB) as an example. The novel adsorbents combine advantages of MOFs and magnetic nanoparticles and possess large capacity, low cost, rapid removal and easy separation of the solid phase, which makes it an excellent sorbent for treatment of wastewaters. The resulting magnetic MOFs composites (also known as MFCs) have large surface areas (79.52 m(2) g(-1)), excellent magnetic response (14.89 emu g(-1)), and large mesopore volume (0.09 cm(3) g(-1)), as well as good chemical inertness and mechanical stability. Adsorption was not drastically affected by pH, suggesting π-π stacking interaction and/or hydrophobic interactions between MB and MFCs. Kinetic parameters followed pseudo-second-order kinetics and adsorption was described by the Freundlich isotherm. Adsorption capacity was 84 mg MB g(-1) at an initial MB concentration of 30 mg L(-1), which increased to 245 mg g(-1) when the initial MB concentration was 300 mg L(-1). This capacity was much greater than most other adsorbents reported in the literature. In addition, MFC adsorbents possess excellent reusability, being effective after at least five consecutive cycles.

  14. Synthesis of magnetic metal-organic framework (MOF) for efficient removal of organic dyes from water

    PubMed Central

    Zhao, Xiaoli; Liu, Shuangliu; Tang, Zhi; Niu, Hongyun; Cai, Yaqi; Meng, Wei; Wu, Fengchang; Giesy, John P.

    2015-01-01

    A novel, simple and efficient strategy for fabricating a magnetic metal-organic framework (MOF) as sorbent to remove organic compounds from simulated water samples is presented and tested for removal of methylene blue (MB) as an example. The novel adsorbents combine advantages of MOFs and magnetic nanoparticles and possess large capacity, low cost, rapid removal and easy separation of the solid phase, which makes it an excellent sorbent for treatment of wastewaters. The resulting magnetic MOFs composites (also known as MFCs) have large surface areas (79.52 m2 g−1), excellent magnetic response (14.89 emu g−1), and large mesopore volume (0.09 cm3 g−1), as well as good chemical inertness and mechanical stability. Adsorption was not drastically affected by pH, suggesting π–π stacking interaction and/or hydrophobic interactions between MB and MFCs. Kinetic parameters followed pseudo-second-order kinetics and adsorption was described by the Freundlich isotherm. Adsorption capacity was 84 mg MB g−1 at an initial MB concentration of 30 mg L−1, which increased to 245 mg g−1 when the initial MB concentration was 300 mg L−1. This capacity was much greater than most other adsorbents reported in the literature. In addition, MFC adsorbents possess excellent reusability, being effective after at least five consecutive cycles. PMID:26149818

  15. Synthesis of magnetic metal-organic framework (MOF) for efficient removal of organic dyes from water

    NASA Astrophysics Data System (ADS)

    Zhao, Xiaoli; Liu, Shuangliu; Tang, Zhi; Niu, Hongyun; Cai, Yaqi; Meng, Wei; Wu, Fengchang; Giesy, John P.

    2015-07-01

    A novel, simple and efficient strategy for fabricating a magnetic metal-organic framework (MOF) as sorbent to remove organic compounds from simulated water samples is presented and tested for removal of methylene blue (MB) as an example. The novel adsorbents combine advantages of MOFs and magnetic nanoparticles and possess large capacity, low cost, rapid removal and easy separation of the solid phase, which makes it an excellent sorbent for treatment of wastewaters. The resulting magnetic MOFs composites (also known as MFCs) have large surface areas (79.52 m2 g-1), excellent magnetic response (14.89 emu g-1), and large mesopore volume (0.09 cm3 g-1), as well as good chemical inertness and mechanical stability. Adsorption was not drastically affected by pH, suggesting π-π stacking interaction and/or hydrophobic interactions between MB and MFCs. Kinetic parameters followed pseudo-second-order kinetics and adsorption was described by the Freundlich isotherm. Adsorption capacity was 84 mg MB g-1 at an initial MB concentration of 30 mg L-1, which increased to 245 mg g-1 when the initial MB concentration was 300 mg L-1. This capacity was much greater than most other adsorbents reported in the literature. In addition, MFC adsorbents possess excellent reusability, being effective after at least five consecutive cycles.

  16. Breath measurements as volatile organic compound biomarkers.

    PubMed Central

    Wallace, L; Buckley, T; Pellizzari, E; Gordon, S

    1996-01-01

    A brief review of the uses of breath analysis in studies of environmental exposure to volatile organic compounds (VOCs) is provided. The U.S. Environmental Protection Agency's large-scale Total Exposure Assessment Methodology Studies have measured concentrations of 32 target VOCs in the exhaled breath of about 800 residents of various U.S. cities. Since the previous 12-hr integrated personal air exposures to the same chemicals were also measured, the relation between exposure and body burden is illuminated. Another major use of the breath measurements has been to detect unmeasured pathways of exposure; the major impact of active smoking on exposure to benzene and styrene was detected in this way. Following the earlier field studies, a series of chamber studies have provided estimates of several important physiological parameters. Among these are the fraction, f, of the inhaled chemical that is exhaled under steady-state conditions and the residence times. tau i in several body compartments, which may be associated with the blood (or liver), organs, muscle, and fat. Most of the targeted VOCs appear to have similar residence times of a few minutes, 30 min, several hours, and several days in the respective tissue groups. Knowledge of these parameters can be helpful in estimating body burden from exposure or vice versa and in planning environmental studies, particularly in setting times to monitor breath in studies of the variation with time of body burden. Improvements in breath methods have made it possible to study short-term peak exposure situations such as filling a gas tank or taking a shower in contaminated water. PMID:8933027

  17. Breath measurements as volatile organic compound biomarkers.

    PubMed

    Wallace, L; Buckley, T; Pellizzari, E; Gordon, S

    1996-10-01

    A brief review of the uses of breath analysis in studies of environmental exposure to volatile organic compounds (VOCs) is provided. The U.S. Environmental Protection Agency's large-scale Total Exposure Assessment Methodology Studies have measured concentrations of 32 target VOCs in the exhaled breath of about 800 residents of various U.S. cities. Since the previous 12-hr integrated personal air exposures to the same chemicals were also measured, the relation between exposure and body burden is illuminated. Another major use of the breath measurements has been to detect unmeasured pathways of exposure; the major impact of active smoking on exposure to benzene and styrene was detected in this way. Following the earlier field studies, a series of chamber studies have provided estimates of several important physiological parameters. Among these are the fraction, f, of the inhaled chemical that is exhaled under steady-state conditions and the residence times. tau i in several body compartments, which may be associated with the blood (or liver), organs, muscle, and fat. Most of the targeted VOCs appear to have similar residence times of a few minutes, 30 min, several hours, and several days in the respective tissue groups. Knowledge of these parameters can be helpful in estimating body burden from exposure or vice versa and in planning environmental studies, particularly in setting times to monitor breath in studies of the variation with time of body burden. Improvements in breath methods have made it possible to study short-term peak exposure situations such as filling a gas tank or taking a shower in contaminated water.

  18. BASIC CHEMICAL RESEARCH PROGRAM. ELECTRICAL PROPERTIES OF ORGANIC COMPOUNDS

    DTIC Science & Technology

    BENZENE, *CYANIDES, *HYDROXIDES, *ORGANIC COMPOUNDS, ACETYLENES, ALKYL RADICALS, AMIDES, ANILINES , BENZALDEHYDES, CHEMICAL REACTIONS , CONDENSATION... REACTIONS , ELECTRICAL CONDUCTIVITY, MATERIALS, MEASUREMENT, MONOCYCLIC COMPOUNDS, PHENOLS, PHENYL RADICALS, QUINONES, SOLID STATE PHYSICS, SYNTHESIS.

  19. Method for the removal of carbon or carbon compounds from a waste stream

    SciTech Connect

    Urban, P.

    1983-05-17

    A method for the removal of carbon or carbon compounds from a waste stream generated in an unsupported slurry catalyst process utilized for the hydroconversion of heavy hydrocarbonaceous black oil which stream comprises vanadium sulfide, nickel sulfide and carbon or carbon compounds is disclosed. The carbon or carbon compound is removed by contacting the waste stream with sulfur dioxide at oxidizing conditions to yield a solid residue which contains metal sulfides.

  20. Experimental investigation and modeling of dissolved organic carbon removal by coagulation from seawater.

    PubMed

    Jeong, Sanghyun; Sathasivan, Arumugam; Kastl, George; Shim, Wang Geun; Vigneswaran, Saravanamuthu

    2014-01-01

    Coagulation removes colloidal matters and dissolved organic carbon (DOC) which can cause irreversible membrane fouling. However, how DOC is removed by coagulant is not well-known. Jar test was used to study the removal of hydrophobic and hydrophilic DOC fractions at various doses (0.5-8.0 mg-Fe(+3) L(-1)) of ferric chloride (FeCl3) and pH (5.0-9.0). Natural organic matter (NOM) in seawater and treated seawater were fractionated by liquid chromatography-organic carbon detector (LC-OCD). Compared to surface water, the removal of DOC in seawater by coagulation was remarkably different. Majority of DOC could be easily removed with very low coagulant dose (<5.0 mg-Fe(+3) L(-1)) and the removal efficiency did not vary with pH, but the DOC composition in treated water had significantly changed. Hydrophobic fraction (HB) was better removed at high pH while hydrophilic fraction (HF) was better removed at low pH. A modified model of Kastl et al. (2004) which assumed that the removal occurred by adsorption of un-dissociated compounds onto ferric hydroxide was formulated and successfully validated against the jar test data.

  1. Removal of sulfur-organic polar micropollutants in a membrane bioreactor treating industrial wastewater.

    PubMed

    Reemtsma, Thorsten; Zywicki, Britta; Stueber, Markus; Kloepfer, Achim; Jekel, Martin

    2002-03-01

    While membrane bioreactors (MBR) have proven their large potential to remove bulk organic matter from municipal as well as industrial wastewater, their suitability to remove poorly degradable polar wastewater contaminants is yet unknown. However, this is an important aspect for the achievable effluent quality and in terms of wastewater reuse. We have analyzed two classes of polar sulfur-organic compounds, naphthalene sulfonates and benzothiazoles, by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS) over a period of 3 weeks in the influent and effluent of a full-scale MBR with external ultrafiltration that treats tannery wastewater. While naphthalene monosulfonates were completely removed, total naphthalene disulfonate removal was limited to about 40%, and total benzothiazoles concentration decreased for 87%. Quantitative as well as qualitative data did not indicate an adaptation to or a more complete removal of these polar aromatic compounds by the MBR as compared to literature data on conventional activated sludge treatment. While quality improvements in receiving waters for bulk organic matter are documented and the same can be anticipated for apolar particle-associated contaminants, these data provide no indication that MBR will improve the removal of polar poorly biodegradable organic pollutants.

  2. Volatile Organic Compound Emissions by Agricultural Crops

    NASA Astrophysics Data System (ADS)

    Ormeno, E.; Farres, S.; Gentner, D.; Park, J.; McKay, M.; Karlik, J.; Goldstein, A.

    2008-12-01

    Biogenic Volatile Organic Compounds (BVOCs) participate in ozone and aerosol formation, and comprise a substantial fraction of reactive VOC emission inventories. In the agriculturally intensive Central Valley of California, emissions from crops may substantially influence regional air quality, but emission potentials have not been extensively studied with advanced instrumentation for many important crops. Because crop emissions may vary according to the species, and California emission inventories are constructed via a bottom-up approach, a better knowledge of the emission rate at the species-specific level is critical for reducing uncertainties in emission inventories and evaluating emission model performance. In the present study we identified and quantified the BVOCs released by dominant agricultural crops in California. A screening study to investigate both volatile and semivolatile BVOC fractions (oxygenated VOCs, isoprene, monoterepenes, sesquiterpenes, etc.) was performed for 25 crop species (at least 3 replicates plants each), including branch enclosures of woody species (e.g. peach, mandarin, grape, pistachio) and whole plant enclosures for herbaceous species (e.g. onion, alfalfa, carrot), through a dynamic cuvette system with detection by PTRMS, in-situ GCMS/FID, and collection on carbon-based adsorbents followed by extraction and GCMS analysis. Emission data obtained in this study will allow inclusion of these crops in BVOC emission inventories and air quality simulations.

  3. Volatile organic compound remedial action project

    SciTech Connect

    1991-12-01

    This Environmental Assessment (EA) reviews a proposed project that is planned to reduce the levels of volatile organic compound (VOC) contaminants present in the Mound domestic water supply. The potable and industrial process water supply for Mound is presently obtained from a shallow aquifer via on-site production wells. The present levels of VOCs in the water supply drawn from the on-site wells are below the maximum contaminant levels (MCLs) permissible for drinking water under Safe Drinking Water Act (SDWA; 40 CFR 141); however, Mound has determined that remedial measures should be taken to further reduce the VOC levels. The proposed project action is the reduction of the VOC levels in the water supply using packed tower aeration (PTA). This document is intended to satisfy the requirements of the National Environmental Policy Act (NEPA) of 1969 and associated Council on Environmental Quality regulations (40 CFR parts 1500 through 1508) as implemented through U.S. Department of Energy (DOE) Order 5440.1D and supporting DOE NEPA Guidelines (52 FR 47662), as amended (54 FR 12474; 55 FR 37174), and as modified by the Secretary of Energy Notice (SEN) 15-90 and associated guidance. As required, this EA provides sufficient information on the probable environmental impacts of the proposed action and alternatives to support a DOE decision either to prepare an Environmental Impact Statement (EIS) or issue a Finding of No Significant Impact (FONSI).

  4. FIELD SCREENING FOR HALOGENATED VOLATILE ORGANIC COMPOUNDS

    SciTech Connect

    John F. Schabron; Joseph F. Rovani Jr.; Theresa M. Bomstad

    2002-06-01

    Western Research Institute (WRI) initiated exploratory work towards the development of new field screening methodology and a test kit to measure halogenated volatile organic compounds (VOCs) in the field. Heated diode and corona discharge sensors are commonly used to detect leaks of refrigerants from air conditioners, freezers, and refrigerators. They are both selective to the presence of carbon-halogen bonds. Commercially available heated diode and corona discharge leak detectors were procured and evaluated for halogenated VOC response. The units were modified to provide a digital readout of signal related to VOC concentration. Sensor response was evaluated with carbon tetrachloride and tetrachloroethylene (perchloroethylene, PCE), which represent halogenated VOCs with and without double bonds. The response characteristics were determined for the VOCs directly in headspace in Tedlar bag containers. Quantitation limits in air were estimated. Potential interferences from volatile hydrocarbons, such as toluene and heptane, were evaluated. The effect of humidity was studied also. The performance of the new devices was evaluated in the laboratory by spiking soil samples and monitoring headspace for halogenated VOCs. A draft concept of the steps for a new analytical method was outlined. The results of the first year effort show that both devices show potential utility for future analytical method development work towards the goal of developing a portable test kit for screening halogenated VOCs in the field.

  5. Soil amino compound and carbohydrate contents influenced by organic amendments

    USDA-ARS?s Scientific Manuscript database

    Amino compounds (i. e. amino acids and sugars), and carbohydrates are labile organic components and contribute to the improvement of soil fertility and quality. Animal manure and other organic soil amendments are rich in both amino compounds and carbohydrates, hence organic soil amendments might af...

  6. Investigation of membrane fouling in ultrafiltration using model organic compounds.

    PubMed

    Kweon, J H; Lawler, D F

    2005-01-01

    Natural organic matter (NOM) is known to be the worst foulant in the membrane processes, but the complexities of NOM make it difficult to determine its effects on membrane fouling. Therefore, simple organic compounds (surrogates for NOM) were used in this research to investigate the fouling mechanisms in ultrafiltration. Previous research on NOM components in membrane processes indicated that polysaccharides formed an important part of the fouling cake. Three polysaccharides (dextran, alginic acid, and polygalacturonic acid) and a smaller carbohydrate (tannic acid) were evaluated for their removal in softening (the treatment process in the City of Austin). Two polysaccharides (dextran and alginic acid) were selected and further investigated for their effects on membrane fouling. The two raw organic waters (4 mg/L C) showed quite different patterns of flux decline indicating different fouling mechanisms. Softening pretreatment was effective to reduce flux decline of both waters. The SEM images of the fouled membrane clearly showed the shapes of deposited foulants. The high resolution results of the XPS spectra showed substantially different spectra of carbon, C(1s), in the membrane fouled by two raw organic waters. The XPS was beneficial in determining the relative composition of each fouling material on the membrane surface.

  7. Sorption characteristics of organic compounds on hexadecyltrimethylammonium-smectite

    USGS Publications Warehouse

    Boyd, Stephen A.; Mortland, Max M.; Chiou, Cary T.

    1988-01-01

    When hexadedyltrimethylammonium (HDTMA) ion is exchanged for metal cations like calcium in smectite, the sorptive properties of the clay are greatly modified. The resultant HDTMA-smectite complex behaves as a dual sorbent, in the sorption of organic compounds, in which the mineral fraction functions as a solid adsorbent and the organic (HDTMA) phase as a partition medium. Capacities of mineral adsorption and partition uptake by HDTMA in the HDTMA-smectites are illustrated by sorption of benzene, trichloroethene (TCE), and water as vapors on the dry sample and by sorption of benzene and TCE from water. The exchanged HDTMA in clay is found to be a much more powerful partition medium than ordinary soil organic matter in the uptake of benzene and TCE. Based on this finding, HDTMA-smectite appears to be an effective sorbent for removing organic contaminants from water. It is suggested that such sorptive organo-clay complexes could be used to enhance the containment capabilities of clay landfill liners and bentonite slurry walls.

  8. Ammonia removal from wastewater by ion exchange in the presence of organic contaminants.

    PubMed

    Jorgensen, T C; Weatherley, L R

    2003-04-01

    The scope of this study was the removal of ammonium by ion exchange from simulated wastewater. The study looks at the effect of organics upon ammonium ion exchange equilibrium uptake. The ion exchangers included a natural zeolite clinoptilolite, and two polymeric exchangers, Dowex 50w-x8, and Purolite MN500. The organic compounds studied included citric acid and a number of proteins. The traditional method for removal of ammonium and organic pollutants from wastewater is biological treatment, but ion exchange offers a number of advantages including the ability to handle shock loadings and the ability to operate over a wider range of temperatures. The results show that in most of the cases studied, the presence of organic compounds enhances the uptake of ammonium ion onto the ion exchangers.

  9. Removal of sulfur compounds from combustion product exhaust

    DOEpatents

    Cheng, Dah Y.

    1982-01-01

    A method and device are disclosed for removing sulfur containing contaminents from a combustion product exhaust. The removal process is carried out in two stages wherein the combustion product exhaust is dissolved in water, the water being then heated to drive off the sulfur containing contaminents. The sulfur containing gases are then resolublized in a cold water trap to form a concentrated solution which can then be used as a commercial product.

  10. FISSION PRODUCT REMOVAL FROM ORGANIC SOLUTIONS

    DOEpatents

    Moore, R.H.

    1960-05-10

    The decontamination of organic solvents from fission products and in particular the treatment of solvents that were used for the extraction of uranium and/or plutonium from aqueous acid solutions of neutron-irradiated uranium are treated. The process broadly comprises heating manganese carbonate in air to a temperature of between 300 and 500 deg C whereby manganese dioxide is formed; mixing the manganese dioxide with the fission product-containing organic solvent to be treated whereby the fission products are precipitated on the manganese dioxide; and separating the fission product-containing manganese dioxide from the solvent.

  11. Aqueous phase removal of nitrogen from nitrogen compounds

    DOEpatents

    Fassbender, Alex G.

    1993-01-01

    A method is disclosed for denitrification of compounds containing nitrogen present in aqueous waste streams. The method comprises the steps of (1) identifying the types of nitrogen compounds present in a waste stream, (2) determining the concentrations of nitrogen compounds, (3) balancing oxidized and reduced form of nitrogen by adding a reactant, and (4) heating the mixture to a predetermined reaction temperature from about 300.degree. C. to about 600.degree. C., thereby resulting in less harmful nitrogen and oxygen gas, hydroxides, alcohols, and hydrocarbons.

  12. Method and reaction pathway for selectively oxidizing organic compounds

    DOEpatents

    Camaioni, Donald M.; Lilga, Michael A.

    1998-01-01

    A method of selectively oxidizing an organic compound in a single vessel comprises: a) combining an organic compound, an acid solution in which the organic compound is soluble, a compound containing two oxygen atoms bonded to one another, and a metal ion reducing agent capable of reducing one of such oxygen atoms, and thereby forming a mixture; b) reducing the compound containing the two oxygen atoms by reducing one of such oxygen atoms with the metal ion reducing agent to, 1) oxidize the metal ion reducing agent to a higher valence state, and 2) produce an oxygen containing intermediate capable of oxidizing the organic compound; c) reacting the oxygen containing intermediate with the organic compound to oxidize the organic compound into an oxidized organic intermediate, the oxidized organic intermediate having an oxidized carbon atom; d) reacting the oxidized organic intermediate with the acid counter ion and higher valence state metal ion to bond the acid counter ion to the oxidized carbon atom and thereby produce a quantity of an ester incorporating the organic intermediate and acid counter ion; and e) reacting the oxidized organic intermediate with the higher valence state metal ion and water to produce a quantity of alcohol which is less than the quantity of ester, the acid counter ion incorporated in the ester rendering the carbon atom bonded to the counter ion less reactive with the oxygen containing intermediate in the mixture than is the alcohol with the oxygen containing intermediate.

  13. Reverse osmosis for removing synthetic organics from drinking water: a cost and performance evaluation

    SciTech Connect

    Lykins, B.W.; Clark, R.M.; Fronk, C.A.

    1988-06-01

    Reverse osmosis for removing organic compounds from drinking water has considerable promise. Bench and pilot plant studies on actual waters have shown that several organics proposed for regulation can be removed by reverse osmosis. As membrane technology improves, rejection of more difficult to remove compounds is expected to improve. Also, smaller volumes of concentrate are expected to be produced that can be handled more cost-effectively. One major concern with the use of reverse osmosis is concentrate disposal, which may increase the overall cost of treatment and disposal. The cost of reverse osmosis is very sensitive to such factors as recovery, economies of scale, systems configuration, membrane type, and electric power cost. In certain situations, reverse osmosis is a viable treatment option that is not cost-prohibitive.

  14. Oceanic protection of prebiotic organic compounds from UV radiation

    NASA Technical Reports Server (NTRS)

    Cleaves, H. J.; Miller, S. L.; Bada, J. L. (Principal Investigator)

    1998-01-01

    It is frequently stated that UV light would cause massive destruction of prebiotic organic compounds because of the absence of an ozone layer. The elevated UV flux of the early sun compounds this problem. This applies to organic compounds of both terrestrial and extraterrestrial origin. Attempts to deal with this problem generally involve atmospheric absorbers. We show here that prebiotic organic polymers as well as several inorganic compounds are sufficient to protect oceanic organic molecules from UV degradation. This aqueous protection is in addition to any atmospheric UV absorbers and should be a ubiquitous planetary phenomenon serving to increase the size of planetary habitable zones.

  15. Oceanic protection of prebiotic organic compounds from UV radiation

    NASA Technical Reports Server (NTRS)

    Cleaves, H. J.; Miller, S. L.; Bada, J. L. (Principal Investigator)

    1998-01-01

    It is frequently stated that UV light would cause massive destruction of prebiotic organic compounds because of the absence of an ozone layer. The elevated UV flux of the early sun compounds this problem. This applies to organic compounds of both terrestrial and extraterrestrial origin. Attempts to deal with this problem generally involve atmospheric absorbers. We show here that prebiotic organic polymers as well as several inorganic compounds are sufficient to protect oceanic organic molecules from UV degradation. This aqueous protection is in addition to any atmospheric UV absorbers and should be a ubiquitous planetary phenomenon serving to increase the size of planetary habitable zones.

  16. Removal of basic nitrogen compounds from hydrocarbon liquids

    DOEpatents

    Givens, Edwin N.; Hoover, David S.

    1985-01-01

    A method is provided for reducing the concentration of basic nitrogen compounds in hydrocarbonaceous feedstock fluids used in the refining industry by providing a solid particulate carbonaceous adsorbent/fuel material such as coal having active basic nitrogen complexing sites on the surface thereof and the coal with a hydrocarbonaceous feedstock containing basic nitrogen compounds to facilitate attraction of the basic nitrogen compounds to the complexing sites and the formation of complexes thereof on the surface of the coal. The adsorbent coal material and the complexes formed thereon are from the feedstock fluid to provide a hydrocarbonaceous fluid of reduced basic nitrogen compound concentration. The coal can then be used as fuel for boilers and the like.

  17. Organic compounds in produced waters from shale gas wells.

    PubMed

    Maguire-Boyle, Samuel J; Barron, Andrew R

    2014-01-01

    A detailed analysis is reported of the organic composition of produced water samples from typical shale gas wells in the Marcellus (PA), Eagle Ford (TX), and Barnett (NM) formations. The quality of shale gas produced (and frac flowback) waters is a current environmental concern and disposal problem for producers. Re-use of produced water for hydraulic fracturing is being encouraged; however, knowledge of the organic impurities is important in determining the method of treatment. The metal content was determined by inductively coupled plasma optical emission spectrometry (ICP-OES). Mineral elements are expected depending on the reservoir geology and salts used in hydraulic fracturing; however, significant levels of other transition metals and heavier main group elements are observed. The presence of scaling elements (Ca and Ba) is related to the pH of the water rather than total dissolved solids (TDS). Using gas chromatography mass spectrometry (GC/MS) analysis of the chloroform extracts of the produced water samples, a plethora of organic compounds were identified. In each water sample, the majority of organics are saturated (aliphatic), and only a small fraction comes under aromatic, resin, and asphaltene categories. Unlike coalbed methane produced water it appears that shale oil/gas produced water does not contain significant quantities of polyaromatic hydrocarbons reducing the potential health hazard. Marcellus and Barnett produced waters contain predominantly C6-C16 hydrocarbons, while the Eagle Ford produced water shows the highest concentration in the C17-C30 range. The structures of the saturated hydrocarbons identified generally follows the trend of linear > branched > cyclic. Heterocyclic compounds are identified with the largest fraction being fatty alcohols, esters, and ethers. However, the presence of various fatty acid phthalate esters in the Barnett and Marcellus produced waters can be related to their use in drilling fluids and breaker additives

  18. [The removal of organs and intrusion].

    PubMed

    Breynaert, Sophie; Tournier-Vervliet, Anne

    2015-04-01

    Approaching the family of a brain dead patient to enquire about the deceased's wishes with regard to the donation of their organs is a delicate matter. It is also a difficult time for the medical and paramedical teams, in intensive care as well as the operating theatre. Describing the phenomena of potential intrusions and the methods of guidance and support can help those involved adjust their practice to the specific situation of the families and professionals concerned.

  19. Nitrated Secondary Organic Tracer Compounds in Biomass Burning Smoke

    NASA Astrophysics Data System (ADS)

    Iinuma, Y.; Böge, O.; Gräfe, R.; Herrmann, H.

    2010-12-01

    Natural and human-initiated biomass burning releases large amounts of gases and particles into the atmosphere, impacting climate, environment and affecting public health. Several hundreds of compounds are emitted from biomass burning and these compounds largely originate from the pyrolysis of biopolymers such as lignin, cellulose and hemicellulose. Some of compounds are known to be specific to biomass burning and widely recognized as tracer compounds that can be used to identify the presence of biomass burning PM. Detailed chemical analysis of biomass burning influenced PM samples often reveals the presence compounds that correlated well with levoglucosan, a known biomass burning tracer compound. In particular, nitrated aromatic compounds correlated very well with levoglucosan, indicating that biomass burning as a source for this class of compounds. In the present study, we present evidence for the presence of biomass burning originating secondary organic aerosol (BSOA) compounds in biomass burning influenced ambient PM. These BSOA compounds are typically nitrated aromatic compounds that are produced in the oxidation of precursor compounds in the presence of NOx. The precursor identification was performed from a series of aerosol chamber experiments. m-Cresol, which is emitted from biomass burning at significant levels, is found to be a major precursor compounds for nitrated BSOA compounds found in the ambient PM. We estimate that the total concentrations of these compounds in the ambient PM are comparable to biogenic SOA compounds in winter months, indicating the BSOA contributes important amounts to the regional organic aerosol loading.

  20. [Organisms producing hypolipidemic compounds with antioxidant activity].

    PubMed

    Puzhevskaia, T O; Grammatikova, N E; Bibikova, M V; Katlinskiĭ, A V

    2009-01-01

    Complex compounds produced by fungal cultures of Lecanicilium and Beauveria with both high hypolipidemic and antioxydant activities were screened. Two fractions of the hypolipipidemic compounds with antioxidant activity of 95 and 75% in a dose of 25 mcg/ml were isolated.

  1. Methods of hydrotreating a liquid stream to remove clogging compounds

    DOEpatents

    Minderhoud, Johannes Kornelis [Amsterdam, NL; Nelson, Richard Gene [Katy, TX; Roes, Augustinus Wilhelmus Maria [Houston, TX; Ryan, Robert Charles [Houston, TX; Nair, Vijay [Katy, TX

    2009-09-22

    A method includes producing formation fluid from a subsurface in situ heat treatment process. The formation fluid is separated to produce a liquid stream and a gas stream. At least a portion of the liquid stream is provided to a hydrotreating unit. At least a portion of selected in situ heat treatment clogging compositions in the liquid stream are removed to produce a hydrotreated liquid stream by hydrotreating at least a portion of the liquid stream at conditions sufficient to remove the selected in situ heat treatment clogging compositions.

  2. Effects of tertiary treatment by fungi on organic compounds in a kraft pulp mill effluent.

    PubMed

    Rocha-Santos, Teresa; Ferreira, Filipe; Silva, Lurdes; Freitas, Ana Cristina; Pereira, Ruth; Diniz, Mário; Castro, Luísa; Peres, Isabel; Duarte, Armando Costa

    2010-05-01

    Pulp and paper mills generate a plethora of pollutants depending upon the type of pulping process. Efforts to mitigate the environmental impact of such effluents have been made by developing more effective biological treatment systems in terms of biochemical oxygen demand, chemical oxygen demand, colour and lignin content. This study is the first that reports an evaluation of the effects of a tertiary treatment by fungi (Pleurotus sajor caju, Trametes versicolor and Phanerochaete chrysosporium and Rhizopus oryzae) on individual organic compounds of a Eucalyptus globulus bleached kraft pulp and paper mill final effluent after secondary treatment (final effluent). The tertiary treatment with P. sajor caju, T. versicolor and P. chrysosporium and R. oryzae was performed in batch reactors, which were inoculated with separate fungi species and monitored throughout the incubation period. Samples from effluent after secondary and after tertiary treatment with fungi were analysed for both absorbance and organic compounds. The samples were extracted for organic compounds using solid-phase extraction (SPE) and analysed by gas chromatography-mass spectrometry (GC/MS). The efficiencies of the SPE procedure was evaluated by recovery tests. A total of 38 compounds (carboxylic acids, fatty alcohols, phenolic compounds and sterols) were identified and quantified in the E. globulus bleached kraft pulp mill final effluent after secondary treatment. Recoveries from the extraction procedure were between 98.2% and 99.9%. The four fungi species showed an adequate capacity to remove organic compounds and colour. Tertiary treatment with R. oryzae was able to remove 99% of organic compounds and to reduce absorbance on 47% (270 nm) and 74% (465 nm). P. sajor caju, T. versicolor and P. chrysosporium were able to remove 97%, 92% and 99% of organic compounds, respectively, and reduce 18% (270 nm) to 77% (465 nm), 39% (270 nm) to 58% (465 nm) and 31% (270 nm) to 10% (465 nm) of absorbance

  3. Effect of organic matter on cyanide removal by illuminated titanium dioxide or zinc oxide nanoparticles

    PubMed Central

    2013-01-01

    Effect of different type of organic compounds (humic acid, oxalate, ethylenediaminetetraacetic acid, nitrilotriacetic acid, phenol) on the photocatalytic removal of cyanide with TiO2 or ZnO was studied in this work with variation of the solution pH, contact time, initial cyanide concentration and type of organic compounds. Photocatalytic oxidation efficiency of cyanide with TiO2 was greatly affected by the solution pH. It increased as the solution pH decreased. Also maximum removal of cyanide by ZnO was observed near at neutral pH because of the reduced photocatalytic activity of ZnO at exceedingly low and high pH values originated from either acidic/photochemical corrosion of the catalyst and/or surface passivation with Zn(OH)2. Removal efficiency of cyanide greatly decreased in the presence of humic acid, ethylenediaminetetraacetic acid, nitrilotriacetic acid compared to that without presence of organic compound because of the competitive oxidation as well as surface blocking by relatively large organic compounds. The oxidation pattern of cyanide was better described by first-order kinetic model. Finally photocatalytic reaction with TiO2 or ZnO can be effectively applied to treat synthetic wastewater contaminated with cyanide. PMID:24499704

  4. Charcoal bed operation for optimal organic carbon removal

    SciTech Connect

    Merritt, C.M.; Scala, F.R.

    1995-05-01

    Historically, evaporation, reverse osmosis or charcoal-demineralizer systems have been used to remove impurities in liquid radwaste processing systems. At Nine Mile point, we recently replaced our evaporators with charcoal-demineralizer systems to purify floor drain water. A comparison of the evaporator to the charcoal-demineralizer system has shown that the charcoal-demineralizer system is more effective in organic carbon removal. We also show the performance data of the Granulated Activated Charcoal (GAC) vessel as a mechanical filter. Actual data showing that frequent backflushing and controlled flow rates through the GAC vessel dramatically increases Total Organic Carbon (TOC) removal efficiency. GAC vessel dramatically increases Total Organic Carbon (TOC) removal efficiency. Recommendations are provided for operating the GAC vessel to ensure optimal performance.

  5. Effect of influent aeration on removal of organic matter from coffee processing wastewater in constructed wetlands.

    PubMed

    Rossmann, Maike; Matos, Antonio Teixeira; Abreu, Edgar Carneiro; Silva, Fabyano Fonseca; Borges, Alisson Carraro

    2013-10-15

    The aim of the present study was to evaluate the influence of aeration and vegetation on the removal of organic matter in coffee processing wastewater (CPW) treated in 4 constructed wetlands (CWs), characterized as follows: (i) ryegrass (Lolium multiflorum) cultivated system operating with an aerated influent; (ii) non-cultivated system operating with an aerated influent, (iii) ryegrass cultivated system operating with a non-aerated influent; and (iv) non-cultivated system operating with a non-aerated influent. The lowest average chemical oxygen demand (COD), biochemical oxygen demand (BOD) and total suspended solids (TSS) removal efficiencies of 87, 84 and 73%, respectively, were obtained in the ryegrass cultivated system operating with a non-aerated influent. However, ryegrass cultivation did not influence the removal efficiency of organic matter. Artificial aeration of the CPW, prior to its injection in the CW, did not improve the removal efficiencies of organic matter. On other hand it did contribute to increase the instantaneous rate at which the maximum COD removal efficiency was reached. Although aeration did not result in greater organic matter removal efficiencies, it is important to consider the benefits of aeration on the removal of the other compounds.

  6. Relative Stabilities of Organic Compounds Using Benson's Additivity Rules.

    ERIC Educational Resources Information Center

    Vitale, Dale E.

    1986-01-01

    Shows how the structure-energy principle can be presented in organic chemistry (without having to resort to quantum mechanics) by use of Benson's Additive Rules. Examples of the application to several major classes of organic compounds are given.

  7. Relative Stabilities of Organic Compounds Using Benson's Additivity Rules.

    ERIC Educational Resources Information Center

    Vitale, Dale E.

    1986-01-01

    Shows how the structure-energy principle can be presented in organic chemistry (without having to resort to quantum mechanics) by use of Benson's Additive Rules. Examples of the application to several major classes of organic compounds are given.

  8. Biocatalytic removal of organic sulfur from coal

    SciTech Connect

    Webster, D.A.; Kilbane, J.J. II

    1994-09-09

    The objective is to characterize more completely the biochemical ability of the bacterium, Rhodococcus rhodochrous IGTS8, to cleave carbon-sulfur bonds with emphasis on data that will allow the development of a practical coal biodesulfurization process. Another approach for increasing the desulfurization activity of the IGTS8 cultures is to produce strains genetically that have higher activity. The goal of this part of research is to achieve strain improvement by introducing a stronger promoter using genetic engineering techniques. The promoter regulates the transcription of the genes for the desulfurization enzymes, and a stronger promoter, would up-regulate the expression of these genes, resulting in cells with higher desulfurization activity. Promoter probe vectors are used to identify and isolate promoters from a DNA library of the experimental organism. The major accomplishments have been to obtain high biodesulfurization activity in nonaqueous, media, especially using freeze-dried cells, and to have isolated strong promoters from R. rhodochrous IGTS8 which will be used to engineer the organism to produce strains with higher biocatalytic activity.

  9. Selective removal of organics for water reclamation

    NASA Technical Reports Server (NTRS)

    Murphy, Oliver J.; Hitchens, G. Duncan

    1989-01-01

    Electrolysis has been investigated as a means of purifying waste water. The feasibility of the direct electrochemical oxidation of urea has been demonstrated. Urea levels were reduced from 1200 ppm to 1 ppm forming the basis for a new approach to urine purification where the only consumable is electrical energy. Preliminary estimates of the energy requirements are 270 W/hr per liter of urine. Urea oxidation rates of around 350 mg urea/hr/m2 were observed. It is anticipated that a 1 m2 geometric area of electrode could treat urine for a crew of several persons. The low levels of organic contaminants resulting from this treatment indicate that the approach may have an impact as a post treatment process. Experiments are planned to investigate this later possibility.

  10. Identification of priority organic compounds in groundwater recharge of China.

    PubMed

    Li, Zhen; Li, Miao; Liu, Xiang; Ma, Yeping; Wu, Miaomiao

    2014-09-15

    Groundwater recharge using reclaimed water is considered a promising method to alleviate groundwater depletion, especially in arid areas. Traditional water treatment systems are inefficient to remove all the types of contaminants that would pose risks to groundwater, so it is crucial to establish a priority list of organic compounds (OCs) that deserve the preferential treatment. In this study, a comprehensive ranking system was developed to determine the list and then applied to China. 151 OCs, for which occurrence data in the wastewater treatment plants were available, were selected as candidate OCs. Based on their occurrence, exposure potential and ecological effects, two different rankings of OCs were established respectively for groundwater recharge by surface infiltration and direct aquifer injection. Thirty-four OCs were regarded as having no risks while the remaining 117 OCs were divided into three groups: high, moderate and low priority OCs. Regardless of the recharge way, nonylphenol, erythromycin and ibuprofen were the highest priority OCs; their removal should be prioritized. Also the database should be updated as detecting technology is developed. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Characteristics and transformations of dissolved organic nitrogen in municipal biological nitrogen removal wastewater treatment plants

    NASA Astrophysics Data System (ADS)

    Huo, Shouliang; Xi, Beidou; Yu, Honglei; Qin, Yanwen; Zan, Fengyu; Zhang, Jingtian

    2013-12-01

    Dissolved organic nitrogen (DON) represents most of the dissolved nitrogen in the effluent of biological nitrogen removal (BNR) wastewater treatment plants (WWTPs). The characteristics of wastewater-derived DON in two different WWTPs were investigated by several different methods. The major removals of DON and biodegradable dissolved organic nitrogen (BDON) along the treatment train were observed in the anaerobic process. Dissolved combined amino acids (DCAA) and dissolved free amino acids (DFAA) in the effluent accounted approximately for less than 4% and 1% of the effluent DON, respectively. Approximately half of wastewater-derived DON was capable of passing through a 1 kDa ultrafilter, and low MW DON cannot effectively be removed by BNR processes. More than 80% of effluent DON was composed of hydrophilic compounds, which stimulate algal growth. The study provided important information for future upgrading of WWTPs or the selection of DON removal systems to meet more demanding nitrogen discharge limits.

  12. Detection, Composition and Treatment of Volatile Organic Compounds from Waste Treatment Plants

    PubMed Central

    Font, Xavier; Artola, Adriana; Sánchez, Antoni

    2011-01-01

    Environmental policies at the European and global level support the diversion of wastes from landfills for their treatment in different facilities. Organic waste is mainly treated or valorized through composting, anaerobic digestion or a combination of both treatments. Thus, there are an increasing number of waste treatment plants using this type of biological treatment. During waste handling and biological decomposition steps a number of gaseous compounds are generated or removed from the organic matrix and emitted. Different families of Volatile Organic Compounds (VOC) can be found in these emissions. Many of these compounds are also sources of odor nuisance. In fact, odors are the main source of complaints and social impacts of any waste treatment plant. This work presents a summary of the main types of VOC emitted in organic waste treatment facilities and the methods used to detect and quantify these compounds, together with the treatment methods applied to gaseous emissions commonly used in composting and anaerobic digestion facilities. PMID:22163835

  13. FIELD SCREENING FOR HALOGENATED VOLATILE ORGANIC COMPOUNDS

    SciTech Connect

    John F. Schabron; Joseph F. Rovani, Jr.; Theresa M. Bomstad

    2003-07-01

    Western Research Institute (WRI) is continuing work toward the development of new screening methodology and a test kit to measure halogenated volatile organic compounds (VOCs) in the field. Heated diode and corona discharge sensors are commonly used to detect leaks of refrigerants from air conditioners, freezers, and refrigerators. They are both selective to the presence of halogens. In prior work, the devices were tested for response to carbon tetrachloride, heptane, toluene, and water vapors. In the current work, sensor response was evaluated with sixteen halogenated VOCs relative to carbon tetrachloride. The results show that the response of the various chlorinated VOCs is within an order of magnitude of the response to carbon tetrachloride for each of the sensors. Thus, for field screening a single response factor can be used. Both types of leak detectors are being further modified to provide an on-board LCD signal readout, which is related to VOC concentration. The units will be fully portable and will operate with 115-V line or battery power. Signal background, noise level, and response data on the Bacharach heated diode detector and the TIF corona discharge detector show that when the response curves are plotted against the log of concentration, the plot is linear to the upper limit for the particular unit, with some curvature at lower levels. When response is plotted directly against concentration, the response is linear at the low end and is curved at the high end. The dynamic ranges for carbon tetrachloride of the two devices from the lower detection limit (S/N=2) to signal saturation are 4-850 vapor parts per million (vppm) for the corona discharge unit and 0.01-70 vppm for the heated diode unit. Additional circuit modifications are being made to lower the detection limit and increase the dynamic response range of the corona discharge unit. The results indicate that both devices show potential utility for future analytical method development work toward

  14. REMOVAL OF ENDOCRINE DISRUPTING COMPOUNDS USING DRINKING WATER TREATMENT PROCESSES

    EPA Science Inventory

    A growing body of scientific information has shown that man-made industrial chemicals and pesticides may interfere with the normal functioning of human and wildlife endocrine systems. These agents are referred to collectively as endocrine disrupting compounds (EDCs) and they are ...

  15. REMOVAL OF ENDOCRINE DISRUPTING COMPOUNDS USING DRINKING WATER TREATMENT PROCESSES

    EPA Science Inventory

    A growing body of scientific information has shown that man-made industrial chemicals and pesticides may interfere with the normal functioning of human and wildlife endocrine systems. These agents are referred to collectively as endocrine disrupting compounds (EDCs) and they are ...

  16. Membrane bioreactor for control of volatile organic compound emissions

    SciTech Connect

    Ergas, S.J.; McGrath, M.S.

    1997-06-01

    A membrane bioreactor system that overcomes many of the limitations of conventional compost biofilters is described. The system utilizes microporous hydrophobic hollow fiber membranes for mass transfer of volatile organic compounds (VOCs) from the gas phase to a microbially active liquid phase. The reactor design provides a high biomass concentration, a method for wasting biomass, and a method for addition of pH buffers, nutrients, cometabolites, and/or other amendments. A theoretical model is developed, describing mass transfer and biodegradation in the membrane bioreactor. Reactor performance was determined in a laboratory scale membrane bioreactor over a range of gas loading rates using toluene as a model VOC. Toluene removal efficiency was greater than 98% at an inlet concentration of 100 ppm, and a gas residence time of less than 2 s. Factors controlling bioreactor performance were determined through both experiments and theoretical modeling to include: compound Henry`s law constant, membrane specific surface area, gas and VOC loading rates, liquid phase turbulence, and biomass substrate utilization rate.

  17. Design for total organics removal at Cincinnati

    SciTech Connect

    DeMarco, J.; Hartman, D.J.; Metz, D.M.

    1992-01-01

    The industrial Ohio River is the source water for Cincinnati Water Work's (CWW) California surface water treatment plant. As is true for many industrial rivers, a large number of organic contaminants can be found in trace concentrations in the Ohio River. Many Cincinnati citizens are concerned about the quality of the industrial source water because of the frequent spills and unauthorized discharges that occur each year. Because of citizen and utility manager concerns, granular activated carbon (GAC) research studies were completed at Cincinnati, Ohio. The results of these studies provided the impetus for a full-scale GAC addition to the existing Ohio River Plant. Ground breaking and full construction began on March 16, 1989, for a 175 MGD GAC system that includes downflow, gravity GAC adsorption and on-site multiple hearth reactivation. Completion of the 57.7 million dollar GAC addition is expected by 1992. The GAC plant will provide an additional barrier between the contaminants in the industrial Ohio River water source and the consumers of Cincinnati water. The paper will discuss vital but less publicized data and experiences obtained during the completion of the final design and implementation activities of the CWW.

  18. 40 CFR 60.462 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic compounds. 60.462 Section 60.462 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Coil Surface Coating § 60.462 Standards for volatile organic compounds. (a) On and after the date...

  19. 40 CFR 60.492 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.492 Section 60.492 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Beverage Can Surface Coating Industry § 60.492 Standards for volatile organic compounds. On or after...

  20. 40 CFR 60.582 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for volatile organic compounds. 60.582 Section 60.582 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Flexible Vinyl and Urethane Coating and Printing § 60.582 Standard for volatile organic compounds. (a)...

  1. 40 CFR 60.462 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic compounds. 60.462 Section 60.462 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Coil Surface Coating § 60.462 Standards for volatile organic compounds. (a) On and after the date...

  2. 40 CFR 60.462 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic compounds. 60.462 Section 60.462 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Coil Surface Coating § 60.462 Standards for volatile organic compounds. (a) On and after the date...

  3. 40 CFR 60.602 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for volatile organic compounds. 60.602 Section 60.602 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Synthetic Fiber Production Facilities § 60.602 Standard for volatile organic compounds. On and after...

  4. 40 CFR 60.462 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.462 Section 60.462 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Coil Surface Coating § 60.462 Standards for volatile organic compounds. (a) On and after the date...

  5. 40 CFR 60.712 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic compounds. 60.712 Section 60.712 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Magnetic Tape Coating Facilities § 60.712 Standards for volatile organic compounds. Each owner or...

  6. 40 CFR 60.622 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic compounds. 60.622 Section 60.622 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected...

  7. 40 CFR 60.452 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for volatile organic compounds. 60.452 Section 60.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Industrial Surface Coating: Large Appliances § 60.452 Standard for volatile organic compounds. On or...

  8. 40 CFR 60.582 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for volatile organic compounds. 60.582 Section 60.582 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Flexible Vinyl and Urethane Coating and Printing § 60.582 Standard for volatile organic compounds. (a)...

  9. 40 CFR 60.492 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic compounds. 60.492 Section 60.492 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Beverage Can Surface Coating Industry § 60.492 Standards for volatile organic compounds. On or after...

  10. 40 CFR 60.602 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.602 Section 60.602 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Synthetic Fiber Production Facilities § 60.602 Standard for volatile organic compounds. On and after...

  11. 40 CFR 60.742 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic compounds. 60.742 Section 60.742 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Polymeric Coating of Supporting Substrates Facilities § 60.742 Standards for volatile organic compounds....

  12. 40 CFR 60.452 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for volatile organic compounds. 60.452 Section 60.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Industrial Surface Coating: Large Appliances § 60.452 Standard for volatile organic compounds. On or...

  13. 40 CFR 60.622 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic compounds. 60.622 Section 60.622 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected...

  14. 40 CFR 60.622 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic compounds. 60.622 Section 60.622 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected...

  15. 40 CFR 60.452 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for volatile organic compounds. 60.452 Section 60.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Industrial Surface Coating: Large Appliances § 60.452 Standard for volatile organic compounds. On or...

  16. 40 CFR 60.452 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for volatile organic compounds. 60.452 Section 60.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Industrial Surface Coating: Large Appliances § 60.452 Standard for volatile organic compounds. On or...

  17. 40 CFR 60.582 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.582 Section 60.582 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Flexible Vinyl and Urethane Coating and Printing § 60.582 Standard for volatile organic compounds. (a)...

  18. 40 CFR 60.582 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for volatile organic compounds. 60.582 Section 60.582 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Flexible Vinyl and Urethane Coating and Printing § 60.582 Standard for volatile organic compounds. (a)...

  19. 40 CFR 60.462 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic compounds. 60.462 Section 60.462 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Coil Surface Coating § 60.462 Standards for volatile organic compounds. (a) On and after the date...

  20. 40 CFR 60.492 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic compounds. 60.492 Section 60.492 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Beverage Can Surface Coating Industry § 60.492 Standards for volatile organic compounds. On or after...

  1. 40 CFR 60.622 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.622 Section 60.622 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected...

  2. 40 CFR 60.712 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic compounds. 60.712 Section 60.712 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Magnetic Tape Coating Facilities § 60.712 Standards for volatile organic compounds. Each owner or...

  3. 40 CFR 60.622 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic compounds. 60.622 Section 60.622 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected...

  4. 40 CFR 60.722 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.722 Section 60.722 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... volatile organic compounds. (a) Each owner or operator of any affected facility which is subject to...

  5. 40 CFR 60.602 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for volatile organic compounds. 60.602 Section 60.602 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Synthetic Fiber Production Facilities § 60.602 Standard for volatile organic compounds. On and after...

  6. 40 CFR 60.742 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic compounds. 60.742 Section 60.742 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Polymeric Coating of Supporting Substrates Facilities § 60.742 Standards for volatile organic compounds....

  7. 40 CFR 60.602 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for volatile organic compounds. 60.602 Section 60.602 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Synthetic Fiber Production Facilities § 60.602 Standard for volatile organic compounds. On and after...

  8. 40 CFR 60.712 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.712 Section 60.712 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Magnetic Tape Coating Facilities § 60.712 Standards for volatile organic compounds. Each owner or...

  9. 40 CFR 60.602 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for volatile organic compounds. 60.602 Section 60.602 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Synthetic Fiber Production Facilities § 60.602 Standard for volatile organic compounds. On and after...

  10. 40 CFR 60.582 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for volatile organic compounds. 60.582 Section 60.582 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Flexible Vinyl and Urethane Coating and Printing § 60.582 Standard for volatile organic compounds. (a)...

  11. 40 CFR 60.742 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic compounds. 60.742 Section 60.742 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Polymeric Coating of Supporting Substrates Facilities § 60.742 Standards for volatile organic compounds....

  12. 40 CFR 60.712 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic compounds. 60.712 Section 60.712 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Magnetic Tape Coating Facilities § 60.712 Standards for volatile organic compounds. Each owner or...

  13. 40 CFR 60.492 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic compounds. 60.492 Section 60.492 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Beverage Can Surface Coating Industry § 60.492 Standards for volatile organic compounds. On or after...

  14. 40 CFR 60.742 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.742 Section 60.742 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Polymeric Coating of Supporting Substrates Facilities § 60.742 Standards for volatile organic compounds....

  15. 40 CFR 60.492 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic compounds. 60.492 Section 60.492 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Beverage Can Surface Coating Industry § 60.492 Standards for volatile organic compounds. On or after...

  16. 40 CFR 60.722 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic compounds. 60.722 Section 60.722 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... volatile organic compounds. (a) Each owner or operator of any affected facility which is subject to...

  17. 40 CFR 60.722 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic compounds. 60.722 Section 60.722 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... volatile organic compounds. (a) Each owner or operator of any affected facility which is subject to...

  18. 40 CFR 60.722 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic compounds. 60.722 Section 60.722 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... volatile organic compounds. (a) Each owner or operator of any affected facility which is subject to...

  19. 40 CFR 60.722 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic compounds. 60.722 Section 60.722 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... volatile organic compounds. (a) Each owner or operator of any affected facility which is subject to...

  20. 40 CFR 60.452 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.452 Section 60.452 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Industrial Surface Coating: Large Appliances § 60.452 Standard for volatile organic compounds. On or...

  1. 40 CFR 60.712 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic compounds. 60.712 Section 60.712 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Magnetic Tape Coating Facilities § 60.712 Standards for volatile organic compounds. Each owner or...

  2. 40 CFR 60.742 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic compounds. 60.742 Section 60.742 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Polymeric Coating of Supporting Substrates Facilities § 60.742 Standards for volatile organic compounds....

  3. A Systematic Presentation of Organic Phosphorus and Sulfur Compounds.

    ERIC Educational Resources Information Center

    Hendrickson, James B.

    1985-01-01

    Because the names, interrelations, and oxidation levels of the organic compounds of phosphorus and sulfur tend to confuse students, a simple way to organize these compounds has been developed. The system consists of grouping them by oxidation state and extent of carbon substitution. (JN)

  4. A Systematic Presentation of Organic Phosphorus and Sulfur Compounds.

    ERIC Educational Resources Information Center

    Hendrickson, James B.

    1985-01-01

    Because the names, interrelations, and oxidation levels of the organic compounds of phosphorus and sulfur tend to confuse students, a simple way to organize these compounds has been developed. The system consists of grouping them by oxidation state and extent of carbon substitution. (JN)

  5. Removal of arsenic compounds from spent catecholated polymer

    DOEpatents

    Fish, Richard H.

    1985-01-01

    Described is a process for removing arsenic from petroliferous derived liquids by contacting said liquid at an elevated temperature with a divinylbenzene-crosslinked polystyrene having catechol ligands anchored thereon. Also, described is a process for regenerating spent catecholated polystyrene by removal of the arsenic bound to it from contacting petroliferous liquid as described above and involves: a. treating said spent catecholated polystyrene, at a temperature in the range of about 20.degree. to 100.degree. C. with an aqueous solution of at least one carbonate and/or bicarbonate of ammonium, alkali and alkaline earth metals, said solution having a pH between about 8 and 10 and, b. separating the solids and liquids from each other. Preferably the regeneration treatment is in two steps wherein step (a) is carried out with an aqueous alcoholic carbonate solution containing lower alkyl alcohol, and, steps (a) and (b) are repeated using a bicarbonate.

  6. Cascade air-stripping system for removal of low and semi-volatile organic contaminants

    SciTech Connect

    Jang, Won.

    1989-01-01

    Many hazardous waste sites have been known to have groundwaters contaminated with low volatile, hazardous compounds such as bromoform 1,1,2,2-tetrachloroethane, 1,2-dibromo-3-chloropropane (DBCP), napthalene, and polychlorinated biphenyls (PCBs). In addition, a large number of public water supplies have been reported to have taste and odor problems in drinking water, which are attributed primarily to naturally occurring compounds, such as 2-methylisoborneol (MIB), geosmin, etc. These classes of compounds have very low Henry's Constant, H{sub c}, in the range of 1 to 50 atm. Air-stripping in countercurrent packed towers is a well accepted treatment process for removing volatile organic chemicals (VOCs) from water. The USEPA has identified packed countercurrent air-stripping as not only the least-cost, but also one of the best available technologies for the removal of VOCs. However, the economic viability of this process is limited to volatile compounds of H{sub c} value greater than SO atm. A novel modification of the conventional countercurrent air-stripping process, introduced as cascade air-stripping was proposed for cost effective removal of these classes of compounds from water and at hazardous waste spill-sites. The main objectives of this study were to demonstrate the concept of cascade air-stripping; to compare cascade air-stripping with conventional air-stripping under identical conditions; and to verify the hypothesis that the cascade system is superior to the conventional system at the pilot and prototype scales. Results of the pilot and prototype study showed that the cascade airstrip ping system was a viable and economical approach to remove low and semi-volatile organic compounds from water. The cascade system consistently showed higher removals than the conventional system for both pilot and prototype scale study.

  7. Environmentally friendly organic synthesis using bismuth(III) compounds.

    PubMed

    Krabbe, Scott W; Mohan, Ram S

    2012-01-01

    With increasing environmental concerns, the need for environmentally friendly organic synthesis has gained increased importance. In this regard, bismuth(III) compounds are especially attractive as "green" reagents and catalysts for organic synthesis. Bismuth(III) compounds are remarkably nontoxic, relatively air and moisture stable, and easy to handle. The contributions from our laboratory in the last 5 years in the field of applications of bismuth(III) compounds as catalysts are presented.

  8. Determination of organic compounds in landfill leachates treated by Fenton-Adsorption.

    PubMed

    Ramírez-Sosa, Dorian R; Castillo-Borges, Elba R; Méndez-Novelo, Roger I; Sauri-Riancho, María R; Barceló-Quintal, Manuel; Marrufo-Gómez, José M

    2013-02-01

    The objective of this study was to identify the organic compounds removed from the leachate when treated with Fenton-Adsorption by gas chromatography coupled to mass spectrometry (GC-MS) in order to identify toxic compounds that could be harmful for the environment or human health. The physicochemical characterization of the raw leachate was carried out before and after the Fenton-Adsorption process. The effluent from each stage of this process was characterized: pH, Biological Oxygen Demand (BOD(5)), Chemical Oxygen Demand (COD), Total Organic Carbon (TOC), Total Carbon (TC), Inorganic Carbon (IC), Total Solids (TS), Total Suspended Solids (TSS) and Color. The organic compounds were determined by GC-MS. The removal of COD and color reached over 99% in compliance with the Mexican Standard NOM-001-SEMARNAT-1996, which establishes the maximum permissible limits for contaminants present in wastewater discharges to water and national goods. The chromatographic analysis from the Fenton-Adsorption effluent proved that this treatment removed more than 98% of the organic compounds present in the initial sample. The mono (2-ethylhexyl) ester 1,2-benzenedicarboxylic acid persisted, although it is not considered as toxic compound by the NOM-052-SEMARNAT-2005. Therefore, the treated effluent can be safely disposed of into the environment. Copyright © 2012. Published by Elsevier Ltd.

  9. Fate of alkylphenolic compounds during activated sludge treatment: impact of loading and organic composition.

    PubMed

    McAdam, Ewan J; Bagnall, John P; Soares, Ana; Koh, Yoong K K; Chiu, Tze Y; Scrimshaw, Mark D; Lester, John N; Cartmell, Elise

    2011-01-01

    The impact of loading and organic composition on the fate of alkylphenolic compounds in the activated sludge plant (ASP) has been studied. Three ASP designs comprising carbonaceous, carbonaceous/nitrification, and carbonaceous/nitrification/denitrification treatment were examined to demonstrate the impact of increasing levels of process complexity and to incorporate a spectrum of loading conditions. Based on mass balance, overall biodegradation efficiencies for nonylphenol ethoxylates (NPEOs), short chain carboxylates (NP(1-3)EC) and nonylphenol (NP) were 37%, 59%, and 27% for the carbonaceous, carbonaceous/nitrification, and carbonaceous/nitrification/denitrification ASP, respectively. The presence of a rich community of ammonia oxidizing bacteria does not necessarily facilitate effective alkylphenolic compound degradation. However, a clear correlation between alkylphenolic compound loading and long chain ethoxylate compound biodegradation was determined at the three ASPs, indicating that at higher initial alkylphenolic compound concentrations (or load), greater ethoxylate biotransformation can occur. In addition, the impact of settled sewage organic composition on alkylphenolic compound removal was evaluated. A correlation between the ratio of chemical oxygen demand (COD) to alkylphenolic compound concentration and biomass activity was determined, demonstrating the inhibiting effect of bulk organic matter on alkylphenol polyethoxylate transformation activity. At all three ASPs the biodegradation pathway proposed involves the preferential biodegradation of the amphiphilic ethoxylated compounds, after which the preferential attack of the lipophilic akylphenol moiety occurs. The extent of ethoxylate biodegradation is driven by the initial alkylphenolic compound concentration and the proportion of COD constituted by the alkylphenol polyethoxylates (APEOs) and their metabolites relative to the bulk organic concentration of the sewage composed of proteins, acids, fats

  10. [Removal of red tide organisms by organo-modified bentonite].

    PubMed

    Deng, Yuesong; Xu, Zirong; Xia, Meisheng; Ye, Ying; Hu, Caihong

    2004-01-01

    A series of organo-bentonites were synthesized by exchanging cation surfactants such as cyltrimethylammonium bromide and cetyltrimethylammonium to remove red tide organisms Skeletonema costatum. The results showed that the removal rate of Skeletonema costatum by the bentonites was in the order of cyltrimethylammonium surfactant modified iron pillared bentonite > cetyltrimethylammoium surfactant modified iron pillared bentonite > iron pillared bentonite > cyltrimethylammonium surfactant modified sodium bentonite > cetyltrimethylammoium surfactant modified > sodium bentonite. The removal rate of Skeletonema costatum was related to the length of alkyl chains and the amount of cation surfactants exchanged on bentonites.

  11. Quantifying commuter exposures to volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Kayne, Ashleigh

    Motor-vehicles can be a predominant source of air pollution in cities. Traffic-related air pollution is often unavoidable for people who live in populous areas. Commuters may have high exposures to traffic-related air pollution as they are close to vehicle tailpipes. Volatile organic compounds (VOCs) are one class of air pollutants of concern because exposure to VOCs carries risk for adverse health effects. Specific VOCs of interest for this work include benzene, toluene, ethylbenzene, and xylenes (BTEX), which are often found in gasoline and combustion products. Although methods exist to measure time-integrated personal exposures to BTEX, there are few practical methods to measure a commuter's time-resolved BTEX exposure which could identify peak exposures that could be concealed with a time-integrated measurement. This study evaluated the ability of a photoionization detector (PID) to measure commuters' exposure to BTEX using Tenax TA samples as a reference and quantified the difference in BTEX exposure between cyclists and drivers with windows open and closed. To determine the suitability of two measurement methods (PID and Tenax TA) for use in this study, the precision, linearity, and limits of detection (LODs) for both the PID and Tenax TA measurement methods were determined in the laboratory with standard BTEX calibration gases. Volunteers commuted from their homes to their work places by cycling or driving while wearing a personal exposure backpack containing a collocated PID and Tenax TA sampler. Volunteers completed a survey and indicated if the windows in their vehicle were open or closed. Comparing pairs of exposure data from the Tenax TA and PID sampling methods determined the suitability of the PID to measure the BTEX exposures of commuters. The difference between BTEX exposures of cyclists and drivers with windows open and closed in Fort Collins was determined. Both the PID and Tenax TA measurement methods were precise and linear when evaluated in the

  12. Catalytic combustion of volatile organic compounds.

    PubMed

    Everaert, K; Baeyens, J

    2004-06-18

    Despite the success of adsorption and thermal incineration of (C)VOC emissions, there is still a need for research on techniques which are both economically more favorable and actually destroy the pollutants rather than merely remove them for recycling elsewhere in the biosphere. The catalytic destruction of (C)VOC to CO2, H2O and HCl/Cl2 appears very promising in this context and is the subject of the present paper. The experiments mainly investigate the catalytic combustion of eight target compounds, all of which are commonly encountered in (C)VOC emissions and/or act as precursors for the formation of PCDD/F. Available literature on the different catalysts active in the oxidation of (C)VOC is reviewed and the transition metal oxide complex V2O5-WO3/TiO2 appears most suitable for the current application. Different reactor geometries (e.g. fixed pellet beds, honeycombs, etc.) are also described. In this research a novel catalyst type is introduced, consisting of a V2O5-WO3/TiO2 coated metal fiber fleece. The conversion of (C)VOC by thermo-catalytic reactions is governed by both reaction kinetics and reaction equilibrium. Full conversion of all investigated VOC to CO2, Cl2, HCl and H2O is thermodynamically feasible within the range of experimental conditions used in this work (260-340 degrees C, feed concentrations 30-60 ppm). A first-order rate equation is proposed for the (C)VOC oxidation reactions. The apparent rate constant is a combination of reaction kinetics and mass transfer effects. The oxidation efficiencies were measured with various (C)VOC in the temperature range of 260-340 degrees C. Literature data for oxidation reactions in fixed beds and honeycomb reactors are included in the assessment. Mass transfer resistances are calculated and are generally negligible for fleece reactors and fixed pellet beds, but can be of importance for honeycomb monoliths. The experimental investigations demonstrate: (i) that the conversion of the hydrocarbons is

  13. Emerging site characterization technologies for volatile organic compounds

    SciTech Connect

    Rohay, V.J.; Last, G.V.

    1992-05-01

    A Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) expedited response action (ERA) has been initiated at Hanford Site`s 200 West Area for the removal of carbon tetrachloride from the unsaturated soils. In coordination with the ERA, innovative technology demonstrations are being conducted as part of DOE`s Volatile Organic Compounds -- Arid Integrated Demonstration in an effort to improve upon baseline technologies. Improved methods for accessing, sampling, and analyzing soil and soil-vapor contaminants is a high priority. Sonic drilling is being evaluated as an alternative to cable-tool drilling, while still providing the advantages of reliability, containment, and waste minimization. Applied Research Associates, Inc. used their cone penetrometer in the 200 West Area to install a permanent soil-gas monitoring probe and to collect soil-gas profile data. However, successful application of this technology will require the development of an improved ability to penetrate coarse gravel units. A Science and Engineering Associates Membrane Instrumentation and Sampling Technique (SEAMIST) system designed for collecting in situ soil samples and air permeability data in between drilling runs at variable depths is being tested in 200 West Area boreholes. Analytical technologies scheduled for testing include supercritical fluid extraction and analysis for non- and semi-volatile organic co-contaminants and an unsaturated flow apparatus developed by Washington State University for the measurement of transport parameters.

  14. Emerging site characterization technologies for volatile organic compounds

    SciTech Connect

    Rohay, V.J.; Last, G.V.

    1992-05-01

    A Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) expedited response action (ERA) has been initiated at Hanford Site's 200 West Area for the removal of carbon tetrachloride from the unsaturated soils. In coordination with the ERA, innovative technology demonstrations are being conducted as part of DOE's Volatile Organic Compounds -- Arid Integrated Demonstration in an effort to improve upon baseline technologies. Improved methods for accessing, sampling, and analyzing soil and soil-vapor contaminants is a high priority. Sonic drilling is being evaluated as an alternative to cable-tool drilling, while still providing the advantages of reliability, containment, and waste minimization. Applied Research Associates, Inc. used their cone penetrometer in the 200 West Area to install a permanent soil-gas monitoring probe and to collect soil-gas profile data. However, successful application of this technology will require the development of an improved ability to penetrate coarse gravel units. A Science and Engineering Associates Membrane Instrumentation and Sampling Technique (SEAMIST) system designed for collecting in situ soil samples and air permeability data in between drilling runs at variable depths is being tested in 200 West Area boreholes. Analytical technologies scheduled for testing include supercritical fluid extraction and analysis for non- and semi-volatile organic co-contaminants and an unsaturated flow apparatus developed by Washington State University for the measurement of transport parameters.

  15. The role of ozonation and activated carbon filtration in the natural organic matter removal from drinking water.

    PubMed

    Matilainen, A; Iivari, P; Sallanko, J; Heiska, E; Tuhkanen, T

    2006-10-01

    Aquatic natural organic matter is one of the most important problems in the drinking water treatment process design and development. In this study, the removal of the natural organic matter was followed both in the full-scale drinking water treatment process and in the pilot-scale studies. The full-scale process consisted of coagulation, flocculation and flotation, sand filtration, ozonation, activated carbon filtration and disinfection. The aim of the pilot study was to investigate the influence of the dose and contact time of ozonation, and also the impact of activated carbon filtration, on the removal efficiency of organic matter. Several methods, including high-performance size-exclusion chromatography, total organic carbon content and assimilable organic carbon content measurements were used to characterize the behaviour of organic matter and its removal efficiency. On the full-scale process, total organic carbon was removed by over 90 %. According to size-exclusion measurements, chemical coagulation removed the high molar mass organic matter with an efficiency of 98%. The ozonation further removed the smaller molar mass fraction compounds by about 27%, while residual higher molar mass matter remained quite unaltered. Activated carbon filtration removed primarily intermediate and low molar mass organic matter. In the pilot-tests, conducted with sand filtered water from the full-scale process, it was noticed, that the ozonation removed primarily smaller organic compounds. The amount of assimilable organic carbon increased with increasing ozone dose, up to 0.4 mg l(-1) with the highest ozone dose of 4.0 mg 1(-1). The activated carbon filtration removed the assimilable organic carbon. Total organic carbon content was not reduced in ozonation.

  16. Combined chemical and microbiological removal of organic sulfur from coal. Technical report, September 1, 1990--August 31, 1991

    SciTech Connect

    Raphaelian, L.A.

    1991-12-31

    The objective of this work is to investigate techniques for chemically converting the sulfur containing organic compounds in coal to compounds that can be treated microbiologically to remove the organically bound sulfur. The goal is to achieve an economically feasible mild chemical oxidation of the organic sulfur in a representative Illinois Basin coal by converting the sulfur to sulfoxides and sulfones; the carbon sulfur bond in the sulfoxides and sulfones would then be broken microbiologically and the sulfur removed from the coal as sulfate.

  17. Preliminary classification of characteristic organic gunshot residue compounds.

    PubMed

    Goudsmits, Ellen; Sharples, George P; Birkett, Jason W

    2016-12-01

    For the first time, a classification system for organic gunshot residue (OGSR) compounds with respect to the confirmation of OGSR materials is presented. There are 136 compounds considered to be associated with OGSR that have been highlighted in the literature. Many of these compounds could be classified as being ubiquitous in the environment and thus their detection as characteristic components of OGSR could cause issues with the interpretation of chemical ballistic evidence. The proposed system aims to address this problem by classifying OGSR compounds based on their forensic relevance with respect to the confirmation of GSR materials. To increase the forensic relevance of such a system, the large number of OGSR compounds reported in the literature has been decreased to 20 OGSR compounds based on the organic chemical composition of over 200 propellant powders. Occupational and environmental materials also associated with OGSR compounds have been considered.

  18. Biodegradability of pharmaceutical industrial wastewater and formation of recalcitrant organic compounds during aerobic biological treatment.

    PubMed

    Mascolo, G; Balest, L; Cassano, D; Laera, G; Lopez, A; Pollice, A; Salerno, C

    2010-04-01

    The biodegradability of different wastewater samples originated from the industrial production of three pharmaceuticals (naproxen, acyclovir, and nalidixic acid) was performed through the standard Zahn-Wellens test. Moreover, the wastewater composition before and during the test was evaluated in terms of parent compounds and main metabolites by LC/MS, and the biodegradability of the parent compounds was also assessed by performing extra Zahn-Wellens tests on synthetic solutions. The results, besides showing the relatively good biodegradability of acyclovir and naproxen, evidenced the masking role of the organic matrices, especially in the case of nalidixic acid. The latter compound showed to be recalcitrant and persistent, despite the apparently good performance of the Zahn-Wellens test. Deeper evaluation evidenced that the biodegradation of high concentrations of organic solvents and other biodegradable compound tended to "hide" the lack of removal of the target compound. Copyright 2009 Elsevier Ltd. All rights reserved.

  19. Organic compounds in circumstellar and interstellar environments.

    PubMed

    Kwok, Sun

    2015-06-01

    Recent research has discovered that complex organic matter is prevalent throughout the Universe. In the Solar System, it is found in meteorites, comets, interplanetary dust particles, and planetary satellites. Spectroscopic signatures of organics with aromatic/aliphatic structures are also found in stellar ejecta, diffuse interstellar medium, and external galaxies. From space infrared spectroscopic observations, we have found that complex organics can be synthesized in the late stages of stellar evolution. Shortly after the nuclear synthesis of the element carbon, organic gas-phase molecules are formed in the stellar winds, which later condense into solid organic particles. This organic synthesis occurs over very short time scales of about a thousand years. In order to determine the chemical structures of these stellar organics, comparisons are made with particles produced in the laboratory. Using the technique of chemical vapor deposition, artificial organic particles have been created by injecting energy into gas-phase hydrocarbon molecules. These comparisons led us to believe that the stellar organics are best described as amorphous carbonaceous nanoparticles with mixed aromatic and aliphatic components. The chemical structures of the stellar organics show strong similarity to the insoluble organic matter found in meteorites. Isotopic analysis of meteorites and interplanetary dust collected in the upper atmospheres have revealed the presence of pre-solar grains similar to those formed in old stars. This provides a direct link between star dust and the Solar System and raises the possibility that the early Solar System was chemically enriched by stellar ejecta with the potential of influencing the origin of life on Earth.

  20. Organic Compounds in Circumstellar and Interstellar Environments

    NASA Astrophysics Data System (ADS)

    Kwok, Sun

    2015-06-01

    Recent research has discovered that complex organic matter is prevalent throughout the Universe. In the Solar System, it is found in meteorites, comets, interplanetary dust particles, and planetary satellites. Spectroscopic signatures of organics with aromatic/aliphatic structures are also found in stellar ejecta, diffuse interstellar medium, and external galaxies. From space infrared spectroscopic observations, we have found that complex organics can be synthesized in the late stages of stellar evolution. Shortly after the nuclear synthesis of the element carbon, organic gas-phase molecules are formed in the stellar winds, which later condense into solid organic particles. This organic synthesis occurs over very short time scales of about a thousand years. In order to determine the chemical structures of these stellar organics, comparisons are made with particles produced in the laboratory. Using the technique of chemical vapor deposition, artificial organic particles have been created by injecting energy into gas-phase hydrocarbon molecules. These comparisons led us to believe that the stellar organics are best described as amorphous carbonaceous nanoparticles with mixed aromatic and aliphatic components. The chemical structures of the stellar organics show strong similarity to the insoluble organic matter found in meteorites. Isotopic analysis of meteorites and interplanetary dust collected in the upper atmospheres have revealed the presence of pre-solar grains similar to those formed in old stars. This provides a direct link between star dust and the Solar System and raises the possibility that the early Solar System was chemically enriched by stellar ejecta with the potential of influencing the origin of life on Earth.

  1. Measurement and removal of bioconcentratable compounds in refinery effluents

    SciTech Connect

    Gala, W.R.; Dorn, P.B.; Means, J.C.; Jenkins, K.D.; Folwarkow, S.

    1994-12-31

    Public concern regarding the presence of persistent, bioconcentratable compounds in fish and shellfish has led the petroleum industry to investigate methods for the measurement of bioconcentratable compounds in refinery effluents. Research has focused on developing methods to measure polycyclic aromatic hydrocarbons (PAHs) and other hydrocarbons directly in the effluent and in bivalves exposed to refinery effluents in the field and in the laboratory. Results from a multi-refinery study in the San Francisco Bay Area using selective ion monitoring GC/MS-MS indicated that alkylated and non-substituted 2--3 ring PAHs are rarely present in refinery effluents at concentrations greater than 100 ng/L. Higher MW PAHs were rarely detected. PAHs did not substantially bioconcentrate in bivalves exposed in the laboratory to refinery effluent and reference sea water. Total PAHs were generally less than 50 {mu}g/g in the effluent-exposed bivalves. A comparison of the waste water treatment facilities at each refinery suggest that biological treatment already required by existing regulations is sufficient to reduce PAH concentrations to these low levels.

  2. Phosphatase hydrolysis of organic phosphorus compounds

    USDA-ARS?s Scientific Manuscript database

    Phosphatases are diverse groups of enzymes that deserve special attention because of the significant roles they play in mineralizing organic phosphorus (P) into inorganic available form. For getting more insight on the enzymatically hydrolysis of organic P, in this work, we compared the catalytic pa...

  3. Extended structures and physicochemical properties of uranyl-organic compounds.

    PubMed

    Wang, Kai-Xue; Chen, Jie-Sheng

    2011-07-19

    The ability of uranium to undergo nuclear fission has been exploited primarily to manufacture nuclear weapons and to generate nuclear power. Outside of its nuclear physics, uranium also exhibits rich chemistry, and it forms various compounds with other elements. Among the uranium-bearing compounds, those with a uranium oxidation state of +6 are most common and a particular structural unit, uranyl UO(2)(2+) is usually involved in these hexavalent uranium compounds. Apart from forming solids with inorganic ions, the uranyl unit also bonds to organic molecules to generate uranyl-organic coordination materials. If appropriate reaction conditions are employed, uranyl-organic extended structures (1-D chains, 2-D layers, and 3-D frameworks) can be obtained. Research on uranyl-organic compounds with extended structures allows for the exploration of their rich structural chemistry, and such studies also point to potential applications such as in materials that could facilitate nuclear waste disposal. In this Account, we describe the structural features of uranyl-organic compounds and efforts to synthesize uranyl-organic compounds with desired structures. We address strategies to construct 3-D uranyl-organic frameworks through rational selection of organic ligands and the incorporation of heteroatoms. The UO(2)(2+) species with inactive U═O double bonds usually form bipyramidal polyhedral structures with ligands coordinated at the equatorial positions, and these polyhedra act as primary building units (PBUs) for the construction of uranyl-organic compounds. The geometry of the uranyl ions and the steric arrangements and functionalities of organic ligands can be exploited in the the design of uranyl--organic extended structures, We also focus on the investigation of the promising physicochemical properties of uranyl-organic compounds. Uranyl-organic materials with an extended structure may exhibit attractive properties, such as photoluminescence, photocatalysis

  4. Integrating organic micropollutant removal into tertiary filtration: Combining PAC adsorption with advanced phosphorus removal.

    PubMed

    Altmann, Johannes; Sperlich, Alexander; Jekel, Martin

    2015-11-01

    Direct addition of powdered activated carbon (PAC) to a deep-bed filter was investigated at pilot-scale as a single advanced treatment stage for simultaneous removal of organic micropollutants (OMPs) and phosphorus from secondary effluent. PAC doses of 10-50 mg/L were assessed with regard to their impacts on filter performance and removal of 15 selected OMPs over a period of 18 months. The PAC was effectively retained by the filter and had no negative effect on filter head loss. Filter runtime until particle breakthrough depended mainly on coagulant dose and did not decrease significantly due to the additional PAC load. Removal of suspended solids and phosphorus by coagulation was effective independent of the PAC dose. A PAC dose of 35 mg/L PAC was suitable to remove well-adsorbing OMPs (e.g. carbamazepine, diclofenac) by >80% and medium adsorbing OMPs (e.g. primidone, sulfamethoxazole) by 50-80%. Median removals were 50-80% for well-adsorbing and 30-50% for medium adsorbing OMPs with 20 mg/L PAC. Abatement of all OMPs was low (<50%) with 10 mg/L PAC, possibly because of the high effluent organic matter content (median dissolved organic carbon (DOC) concentrations of 11.2 mg/L). In addition to adsorptive removal, relevant concentration decreases of certain OMPs (e.g. 4-formylaminoantipyrine) were attributed to biological transformation in the filter. Adsorption onto accumulating PAC in the top layer of the filter bed led to improved OMP adsorption with increasing filter runtime. The comparison of OMP removal in the pilot filter with laboratory adsorption tests demonstrates that batch test results can be applied to estimate adsorptive OMP removal in real applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Removal of Organic Pollutants from Water Using Superwetting Materials.

    PubMed

    Li, Lingxiao; Zhang, Junping; Wang, Aiqin

    2017-08-02

    The frequent occurrence of water pollution accidents and the leakage of organic pollutants have caused severe environmental and ecological crisis. It is thus highly imperative to find efficient materials to solve the problem. Inspired by the lotus leaf, superwetting materials are receiving increasing attention in the field of removal of organic pollutants from water. Various superwetting materials have been successfully generated and integrated into devices for removal of organic pollutants from water. On the basis of our previous work in the field, we summarized in this account the progress of removal of (1) floating and underwater insoluble, (2) emulsified insoluble, and (3) both insoluble and soluble organic pollutants from water using superwetting materials including superhydrophobic & superoleophilic materials, superhydrophilic & underwater superoleophobic materials, and materials with controllable wettability. The superwetting materials are in the forms of 2D porous materials, 3D porous materials and particles, etc. Finally, the current state and future challenges in this field are discussed. We hope this account could shed light on the design of novel superwetting materials for efficient removal of organic pollutants from water. © 2017 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Environmental Aspects of Two Volatile Organic Compound Groundwater Treatment Designs at the Rocky Flats Site - 13135

    SciTech Connect

    Michalski, Casey C.; DiSalvo, Rick; Boylan, John

    2013-07-01

    DOE's Rocky Flats Site in Colorado is a former nuclear weapons production facility that began operations in the early 1950's. Because of releases of hazardous substances to the environment, the federally owned property and adjacent offsite areas were placed on the CERCLA National Priorities List in 1989. The final remedy was selected in 2006. Engineered components of the remedy include four groundwater treatment systems that were installed before closure as CERCLA-accelerated actions. Two of the systems, the Mound Site Plume Treatment System and the East Trenches Plume Treatment System, remove low levels of volatile organic compounds using zero-valent iron media, thereby reducing the loading of volatile organic compounds in surface water resulting from the groundwater pathway. However, the zero-valent iron treatment does not reliably reduce all volatile organic compounds to consistently meet water quality goals. While adding additional zero-valent iron media capacity could improve volatile organic compound removal capability, installation of a solar powered air-stripper has proven an effective treatment optimization in further reducing volatile organic compound concentrations. A comparison of the air stripper to the alternative of adding additional zero-valent iron capacity to improve Mound Site Plume Treatment System and East Trenches Plume Treatment System treatment based on several key sustainable remediation aspects indicates the air stripper is also more 'environmentally friendly'. These key aspects include air pollutant emissions, water quality, waste management, transportation, and costs. (authors)

  7. Method for removing organic liquids from aqueous solutions and mixtures

    DOEpatents

    Hrubesh, Lawrence W.; Coronado, Paul R.; Dow, Jerome P.

    2004-03-23

    A method for removing organic liquids from aqueous solutions and mixtures. The method employs any porous material preferably in granular form and having small pores and a large specific surface area, that is hydrophobic so that liquid water does not readily wet its surface. In this method, organics, especially organic solvents that mix with and are more volatile than water, are separated from aqueous solution by preferentially evaporating across the liquid/solid boundary formed at the surfaces of the hydrophobic porous materials. Also, organic solvents that are immiscible with water, preferentially wet the surfaces of the hydrophobic material and are drawn within the porous materials by capillary action.

  8. Engineering and Design: Trace Organic Compounds in Potable Water Supplies

    DTIC Science & Technology

    2007-11-02

    hydro- carbon solvents, low-polarity, low-solu- bility compounds High-molecular-weight compounds Chlorinated hydrocarbon solvents, low or high molecular...and from 500 to 5 micrograms per liter. Figure 8 compares GAC treatment costs with aeration costs for removing different chlorinated hydrocarbons . (7...Inf Iuont corroontratkm of l-1000 Pg/L; daslgn flaw of 1.6 ML/d (0.5 m~d) Figure 8. Cost curves for three chlorinated hydrocarbons . (Source: O. T. Love

  9. Volatile organic compounds and some very volatile organic compounds in new and recently renovated buildings in Switzerland

    NASA Astrophysics Data System (ADS)

    Rothweiler, Heinz; Wäger, Patrick A.; Schlatter, Christian

    Indoor air in new of recently renovated buildings was analysed by using different sorbents and analytical methods. Increased values of total volatile organic compounds (TVOC) were found on Tenax TA (1.6-31.7 mg m -3). Compared to older buildings, the amount of oxygen-containing compounds (aldehydes, ketones, alcohols) especially was elevated. High hexanal concentrations were measured in a significant amount of the houses. Differences of compound patterns were found from building to building. Complaints about discomfort and negative health effects are expected due to volatile organic compounds (VOC) and very volatile organic compounds (VVOC), as well as from low natural ventilation rates in some newly occupied buildings. Odorous compounds (naphthalene, higher aldehydes and alcohols, capronic acid, etc.) were found mainly, but some irritants and suspected sensitizing agents were also found. At the present state of our investigation chemicals causing other known toxic effects do not seem to increase the toxic risk substantially.

  10. Pharmaceutically active compounds: Their removal during slow sand filtration and their impact on slow sand filtration bacterial removal.

    PubMed

    D'Alessio, Matteo; Yoneyama, Bunnie; Kirs, Marek; Kisand, Veljo; Ray, Chittaranjan

    2015-08-15

    Slow sand filtration (SSF) has been widely used as a means of providing potable water due to its efficacy, low cost, and minimal maintenance. Advances in analytical instrumentation have revealed the occurrence of pharmaceutically active compounds (PhACs) in surface water as well as in groundwater. It is unclear if the presence of these compounds in the feed water can interfere with the performances of an SSF unit. The aim of this work was to examine i) the ability of two SSF units to remove six PhACs (caffeine, carbamazepine, 17-β estradiol [E2], estrone [E1], gemfibrozil, and phenazone), and ii) the impact of these PhACs on the removal of bacteria by two SSF units. The presence of PhACs in feed water for SSF can occur in surface waters impacted by wastewater or leakage from sewers and septic tanks, as well as in developing countries where unregulated use and improper disposal are prevalent. Two pilot-scale SSF units were used during the study. Unit B1 was fed with stream water with 1% of primary effluent added, while unit B2 was fed with stream water alone. Although limited removal (<10%) of carbamazepine, gemfibrozil, and phenazone occurred, the complete removal of caffeine, and the partial removal (11-92%) of E2 and E1 were observed in the two SSF units. The results of this study suggest that the occurrence of the selected PhACs, probably estrogens and caffeine, in the feed water at 50 μg L(-1) affected the ability of the schmutzdecke to remove total coliform and Escherichia coli. The bacterial removal achieved within the schmutzdecke dropped from 95% to less than 20% by the end of the study. This decrease in removal may be related to the change in the microbial community within the schmutzdecke. A diverse microbial community, including Bacteroidetes and several classes of Proteobacteria, was replaced by a microbial community in which Gammaproteobacteria was the predominant phylum (99%). Despite the low removal achieved within the schmutzdecke, removal of

  11. Kinetics of model high molecular weight organic compounds biodegradation in soil aquifer treatment.

    PubMed

    Fox, Peter; Makam, Roshan

    2011-10-01

    Soil Aquifer Treatment (SAT) is a process where treated wastewater is purified during transport through unsaturated and saturated zones. Easily biodegradable compounds are rapidly removed in the unsaturated zone and the residual organic carbon is comprised of primarily high molecular weight compounds. This research focuses on flow in the saturated zone where flow conditions are predictable and high molecular weight compounds are degraded. Flow through the saturated zone was investigated with 4 reactors packed with 2 different particle sizes and operated at 4 different flow rates. The objective was to evaluate the kinetics of transformation for high molecular weight organics during SAT. Dextran was used as a model compound to eliminate the complexity associated with studying a mixture of high molecular weight organics. The hydrolysis products of dextran are easily degradable sugars. Batch experiments with media taken from the reactors were used to determine the distribution of microbial activity in the reactors. Zero-order kinetics were observed for the removal of dextran in batch experiments which is consistent with hydrolysis of high molecular weight organics where extracellular enzymes limit the substrate utilization rate. Biomass and microbial activity measurements demonstrated that the biomass was independent of position in the reactors. A Monod based substrate/biomass growth kinetic model predicted the performance of dextran removal in the reactors. The rate limiting step appears to be hydrolysis and the overall rate was not affected by surface area even though greater biomass accumulation occurred as the surface area decreased. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Effects of aqueous-soluble organic compounds on the removal of selected radionuclides from high-level waste part I: Distribution of Sr, Cs, and Tc onto 18 absorbers from an irradiated, organic-containing leachate simulant for Hanford Tank 101-SY

    SciTech Connect

    Marsh, S.F.; Svitra, Z.V.; Bowen, S.M.

    1995-01-01

    Many of the radioactive waste storage tanks at U.S. Department of Energy facilities contain organic compounds that have been degraded by radiolysis and chemical reactions. In this investigation, we measured the effect of some aqueous-soluble organic compounds on the sorption of strontium, cesium, and technetium onto 18 absorbers that offer high sorption of strontium from organic-free solutions. For our test solution we used a leachate from a simulated slurry for Hanford Tank 101-SY that initially contained ethylenediaminetetraacetic acid (EDTA) and then was gamma-irradiated to 34 Mrads. We measured distribution coefficients (Kds) for each element/absorber combination for dynamic contact periods of 30 min, 2 h, and 6 h to obtain information about sorption kinetics. To facilitate comparisons, we include Kd values for these same element/absorber combinations from three organic-free simulant solutions. The Kd values for strontium sorption from the simulant that contained the degraded organics usually decreased by large factors, whereas the Kd values for cesium and technetium sorption were relatively unaffected.

  13. Removing perchlorate from samples to facilitate organics detection by pyrolitic methods

    NASA Astrophysics Data System (ADS)

    von Kiparski, Guntram R.; Parker, David R.; Tsapin, Alexandre I.

    2013-07-01

    Thermal volatilization or pyrolysis of solid samples followed by gas chromatography-mass spectrometry (TV-GC-MS) or other downstream analyses has proven robustness and has been adopted for the extraction of organic compounds for their detection in planetary lander science missions (e.g., Viking Lander GC-MS, Phoenix TEGA, MSL SAM, and the future ExoMars MOMA). Pyrolysis to extract organic compounds from soil has limitations when oxidants co-occur in the analyzed sample unless the desired end product is CO2. Pyrolysis of such soils may result in oxidation of organics to CO2 during heating, and thus make organics characterization difficult, if not impossible. Analytical investigations seeking to identify organics in martian soils containing oxidants could benefit from the deployment of technologies that remove known and putative oxidants prior to thermal volatilization. We conducted a series of experiments in order to determine if a polymeric anion exchange resin, commonly used for removing the perchlorate anion from contaminated municipal water supplies, could sustain its substantial perchlorate removal capability while keeping organic compounds intact for downstream detection. We demonstrated that this resin can strongly bind perchlorate from aqueous solution while simultaneously leaving amino acids substantially unaltered. The perchlorate-binding resin could be easily adopted as a pre-treatment for martian soil extracts to create analytical systems with improved organics characterization capabilities compatible with existing TV-GC-MS systems. We propose this strategy to aid detection and characterization of putative martian organics co-situated with perchlorate at sampling sites.

  14. Removal of pharmaceutical compounds, nitroimidazoles, from waters by using the ozone/carbon system.

    PubMed

    Sánchez-Polo, M; Rivera-Utrilla, J; Prados-Joya, G; Ferro-García, M A; Bautista-Toledo, I

    2008-09-01

    The main objective of this study was to analyze the effectiveness of technologies based on the use of ozone and activated carbon for the removal of nitroimidazoles from water, considering them as model of pharmaceutical compounds. A study was undertaken of the influence of the different operational variables on the effectiveness of each system studied (O(3), O(3)/activated carbon), and on the kinetics involved in each process. Ozone reaction kinetics showed that nitroimidazoles have a low reactivity, with K(O)(3) values <350 M(-1)s(-1) regardless of the nitroimidazole and solution pH considered. However, nitroimidazoles have a high affinity for HO radicals, with radical rate constant (k(HO)) values of around 10(10)M(-1)s(-1). Among the nitroimidazole ozonation by-products, nitrate ions and 3-acetyl-2-oxazolidinone were detected. The presence of activated carbon during nitroimidazole ozonation produces (i) an increase in the removal rate, (ii) a reduction in the toxicity of oxidation by-products, and (iii) a reduction in the concentration of dissolved organic matter. These results are explained by the generation of HO radicals at the O(3)-activated carbon interface.

  15. Modeling the enhanced removal of emerging organic contaminants during MAR through a reactive barrier.

    NASA Astrophysics Data System (ADS)

    Valhondo, Cristina; Carrera, Jesús; Ayora, Carlos; Martinez-Landa, Lurdes; Nödler, Karsten; Licha, Tobias

    2014-05-01

    Artificial recharge of reclaimed water is often proposed as a way of increasing water resources while improving quality. However, it is also feared that recalcitrant organic contaminants (i.e., those that are not completely removed during wastewater treatment) may reach the aquifer. Specifically, emerging organic contaminants (EOCs) have been increasingly detected in surface and ground waters and are becoming a worldwide problem. Most EOCs exhibit higher concentrations in reclaimed water used for artificial recharge than in produced groundwater, indicating that these compounds are retained and/or degraded during infiltration. Removal may be the result of sorption, which depends on organic matter and inorganic surfaces contained in the sediments, and degradation, which depends on redox conditions (some EOCs are preferentially removed under specific redox conditions). To enhance removal and retention processes, we designed a reactive barrier, which consists of compost, sand, clay and is covered by iron oxide. The role of compost is to favor sorption of neutral compounds and to release easily degradable organic carbon, so as to generate diverse redox condition, thus increasing the range of degraded EOCs. The role of iron oxides and clay is to favor sorption of anionic and cationic compounds, respectively. The barrier has been tested in the field proving its ability in promoting diverse redox conditions and indeed improving EOCs removal. However, experimental data do not allow separating sorption from degradation. To do so, we have built a flow and transport model representing the infiltration system and the aquifer beneath. The model has been calibrated against head data, collected during three years that include recharge and natural flow periods, and concentration, collected during a conservative tracer test. The calibrated model was then used to predict the fate of EOCs using sorption and half-lives from the literature. Results confirm that retention and degradation

  16. Sonochemical decomposition of volatile and non-volatile organic compounds--a comparative study.

    PubMed

    Goel, Mukesh; Hongqiang, Hu; Mujumdar, Arun S; Ray, Madhumita Bhowmick

    2004-11-01

    Sonochemical degradation which combines destruction of the target compounds by free radical reaction and thermal cleavage is one of the recent advanced oxidation processes (AOP) and proven to be effective for removing low concentration organic pollutants from aqueous streams. This work describes the degradation of several organic compounds of varying volatility in aqueous solution in two types of ultrasonic reactors. The process variables studied include initial concentration of the organics, temperature, and type of saturated gas. The effects of additional oxidant and electrolyte were also examined. A kinetic model was tested to determine its ability to predict the degradation rate constant of different volatile organic compounds at different initial conditions. A figure of merit for the electrical energy consumption for the two types of ultrasonic reactors is also presented.

  17. Removal of nitrogen compounds from landfill leachate using reverse osmosis with leachate stabilization in a buffer tank.

    PubMed

    Talalaj, Izabela Anna

    2015-01-01

    In this paper, a removal of nitrogen compounds from a landfill leachate during reverse osmosis (RO) was evaluated. The treatment facility consists of a buffer tank and a RO system. The removal rate of N─NH4, [Formula: see text] and [Formula: see text] in the buffer tank reached 14%, 91% and 41%, respectively. The relatively low concentration of organic carbon limits N─NH4 oxidation in the buffer tank. The removal rate for the total organic nitrogen (TON) was 47%. The removal rate in RO was 99% for [Formula: see text], 84.1% for [Formula: see text] and 41% for [Formula: see text]. The accumulation of [Formula: see text] may be the result of a low pH, which before the RO process is reduced to a value of 6.0-6.5. Besides it, the cause for a low removal rate of the [Formula: see text] in the buffer tank and during RO may be free ammonia, which can inhibit the [Formula: see text] oxidation. The removal rates of total inorganic nitrogen and TON in the RO treatment facility were similar being 99% and 98.5%, respectively.

  18. Natural organic matter removal by coagulation during drinking water treatment: a review.

    PubMed

    Matilainen, Anu; Vepsäläinen, Mikko; Sillanpää, Mika

    2010-09-15

    Natural organic matter (NOM) is found in all surface, ground and soil waters. An increase in the amount of NOM has been observed over the past 10-20 years in raw water supplies in several areas, which has a significant effect on drinking water treatment. The presence of NOM causes many problems in drinking water and drinking water treatment processes, including (i) negative effect on water quality by causing colour, taste and odor problems, (ii) increased coagulant and disinfectant doses (which in turn results in increased sludge volumes and production of harmful disinfection by-products), (iii) promoted biological growth in distribution system, and (iv) increased levels of complexed heavy metals and adsorbed organic pollutants. NOM can be removed from drinking water by several treatment options, of which the most common and economically feasible processes are considered to be coagulation and flocculation followed by sedimentation/flotation and sand filtration. Most of the NOM can be removed by coagulation, although, the hydrophobic fraction and high molar mass compounds of NOM are removed more efficiently than hydrophilic fraction and the low molar mass compounds. Thus, enhanced and/or optimized coagulation, as well as new process alternatives for the better removal of NOM by coagulation process has been suggested. In the present work, an overview of the recent research dealing with coagulation and flocculation in the removal of NOM from drinking water is presented. Copyright 2010 Elsevier B.V. All rights reserved.

  19. Bioelectrochemical treatment of table olive brine processing wastewater for biogas production and phenolic compounds removal.

    PubMed

    Marone, A; Carmona-Martínez, A A; Sire, Y; Meudec, E; Steyer, J P; Bernet, N; Trably, E

    2016-09-01

    Industry of table olives is widely distributed over the Mediterranean countries and generates large volumes of processing wastewaters (TOPWs). TOPWs contain high levels of organic matter, salt, and phenolic compounds that are recalcitrant to microbial degradation. This work aims to evaluate the potential of bioelectrochemical systems to simultaneously treat real TOPWs and recover energy. The experiments were performed in potentiostatically-controlled single-chamber systems fed with real TOPW and using a moderate halophilic consortium as biocatalyst. In conventional anaerobic digestion (AD) treatment, ie. where no potential was applied, no CH4 was produced. In comparison, Bio-Electrochemical Systems (BES) showed a maximum CH4 yield of 701 ± 13 NmL CH4·LTOPW(-1) under a current density of 7.1 ± 0.4 A m(-2) and with a coulombic efficiency of 30%. Interestingly, up to 80% of the phenolic compounds found in the raw TOPW (i.e. hydroxytyrosol and tyrosol) were removed. A new theoretical degradation pathway was proposed after identification of the metabolic by-products. Consistently, microbial community analysis at the anode revealed a clear and specific enrichment in anode-respiring bacteria (ARB) from the genera Desulfuromonas and Geoalkalibacter, supporting the key role of these electroactive microorganisms. As a conclusion, bioelectrochemical systems represent a promising bioprocess alternative for the treatment and energy recovery of recalcitrant TOPWs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Enantiomeric and Isotopic Analysis of Organic Compounds in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Cooper, George

    2004-01-01

    Carbonaceous meteorites are relatively enriched in soluble organic compounds. The Murchison and Murray meteorites contain numerous compounds of interest in the study of early solar system organic chemistry and organic compounds of potential importance for the origin of life. These include: amino acids, amides, carboxylic acids, and polyols. This talk will focus on the enantiomeric and isotopic analysis of individual meteoritic compounds - primarily polyol acids. The analyses will determine if, in addition to certain amino acids from Murchison, another potentially important class of prebiotic compounds also contains enantiomeric excesses, i.e., excesses that could have contributed to the current homochirality of life. Preliminary enantiomeric and isotopic (C- 13) measurements of Murchison glyceric acid show that it is indeed extraterrestrial. C-13 and D isotope analysis of meteoritic sugar alcohols (glycerol, threitol, ribitol, etc.) has shown that they are also indigenous to the meteorite.

  1. Enantiomeric and Isotopic Analysis of Organic Compounds in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Cooper, George

    2004-01-01

    Carbonaceous meteorites are relatively enriched in soluble organic compounds. The Murchison and Murray meteorites contain numerous compounds of interest in the study of early solar system organic chemistry and organic compounds of potential importance for the origin of life. These include: amino acids, amides, carboxylic acids, and polyols. This talk will focus on the enantiomeric and isotopic analysis of individual meteoritic compounds - primarily polyol acids. The analyses will determine if, in addition to certain amino acids from Murchison, another potentially important class of prebiotic compounds also contains enantiomeric excesses, i.e., excesses that could have contributed to the current homochirality of life. Preliminary enantiomeric and isotopic (C- 13) measurements of Murchison glyceric acid show that it is indeed extraterrestrial. C-13 and D isotope analysis of meteoritic sugar alcohols (glycerol, threitol, ribitol, etc.) has shown that they are also indigenous to the meteorite.

  2. Passive remediation of chlorinated volatile organic compounds using barometric pumping

    SciTech Connect

    Rossabi, J.; Looney, B.B.; Dilek, C.A.E.; Riha, B.; Rohay, V.J.

    1993-12-31

    The purpose of the Savannah River Integrated Demonstration Program, sponsored by the Department of Energy, is to demonstrate new subsurface characterization, monitoring, and remediation technologies. The interbedded clay and sand layers at the Integrated Demonstration Site (IDS) are contaminated with chlorinated volatile organic compounds (CVOCs). Characterization studies show that the bulk of the contamination is located in the approximately 40 m thick vadose zone. The most successful strategy for removing contaminants of this type from this environment is vapor extraction alone or in combination with other methods such as air sparging or enhanced bioremediation. Preliminary work at the IDS has indicated that natural pressure differences between surface and subsurface air caused by surface barometric fluctuations can produce enough gas flow to make barometric pumping a viable method for subsurface remediation. Air flow and pressure were measured in wells that are across three stratigraphic intervals in the vadose zone` The subsurface pressures were correlated to surface pressure fluctuations but were damped and lagging in phase corresponding to depth and stratum permeability. Piezometer wells screened at lower elevations exhibited a greater phase lag and damping than wells screened at higher elevations where the pressure wave from barometric fluctuations passes through a smaller number of low permeable layers. The phase lag between surface and subsurface pressures results in significant fluxes through these wells. The resultant air flows through the subsurface impacts CVOC fate and transport. With the appropriate controls (e.g. solenoid valves) a naturally driven vapor extraction system can be implemented requiring negligible operating costs yet capable of a large CVOC removal rate (as much as 1--2 kg/day in each well at the IDS).

  3. Green Technology for the Removal of Chloro-Organics from Pulp and Paper Mill Wastewater.

    PubMed

    Choudhary, Ashutosh Kumar; Kumar, Satish; Sharma, Chhaya; Kumar, Vivek

    2015-07-01

    This study evaluates the treatment efficiency of a horizontal subsurface-flow constructed wetland (HSSF-CW) for the removal of chloro-organic compounds from pulp and paper mill wastewater. The surface area of the HSSF-CW unit was 5.25 m² and was planted with Colocasia esculenta. The wastewater was characterized for different chloro-organic compounds, that is, adsorbable organic halides (AOX), chlorophenolics, and chlorinated resin and fatty acids (cRFAs). Under a hydraulic retention time of 5.9 days, the average AOX, chlorophenolics, and cRFA removal from wastewater was 87, 87, and 93%, respectively. Some of the chlorophenolics were found to accumulate in the plant biomass and soil material. The mass balance studies show that a significant fraction of chlorophenolics and cRFA was degraded in the constructed wetland system. Modeling studies were carried out to estimate the first-order area-based removal rate constants (k) for chemical oxygen demand removal. The HSSF-CW was found to be an effective treatment technology for the remediation of pulp and paper mill wastewater.

  4. Trace organics removal using three membrane bioreactor configurations: MBR, IFAS-MBR and MBMBR.

    PubMed

    de la Torre, T; Alonso, E; Santos, J L; Rodríguez, C; Gómez, M A; Malfeito, J J

    2015-01-01

    Seventeen pharmaceutically active compounds and 22 other trace organic pollutants were analysed regularly in the influent and permeate from a semi-real plant treating municipal wastewater. The plant was operated during 29 months with different configurations which basically differed in the type of biomass present in the system. These processes were the integrated fixed-film activated sludge membrane bioreactor (IFAS-MBR), which combined suspended and attached biomass, the moving bed membrane bioreactor (MBMBR) (only attached biomass) and the MBR (only suspended biomass). Moreover, removal rates were compared to those of the wastewater treatment plant (WWTP) operating nearby with conventional activated sludge treatment. Reverse osmosis (RO) was used after the pilot plant to improve removal rates. The highest elimination was found for the IFAS-MBR, especially for hormones (100% removal); this was attributed to the presence of biofilm, which may lead to different conditions (aerobic-anoxic-anaerobic) along its profile, which increases the degradation possibilities, and also to a higher sludge age of the biofilm, which allows complete acclimation to the contaminants. Operating conditions played an important role, high mixed liquor suspended solids (MLSS) and sludge retention time (SRT) being necessary to achieve these high removal rates. Although pharmaceuticals and linear alkylbenzene sulfonates showed high removal rates (65-100%), nonylphenols and phthalate could only be removed to 10-30%. RO significantly increased removal rates to 88% mean removal rate.

  5. SYNTHESIZING ORGANIC COMPOUNDS USING LIGHT-ACTIVATED TIO2

    EPA Science Inventory

    High-value organic compounds have been synthesized successfully from linear and cyclic hydrocarbons, by photocatalytic oxidation using a semiconductor material, titanium dioxide (TiO2). Various hydrocarbons were partially oxgenated in both liquid and gaseous phase reactors usi...

  6. SEPARATION OF VOLATILE ORGANIC COMPOUNDS FROM SURFACTANT SOLUTIONS BY PERVAPORATION

    EPA Science Inventory

    Pervaporation is gradually becoming an accepted and practical method for the recovery of volatile organic compounds (VOCs) from aqueous process and waste streams. As the technolog has matured, new applications for pervaporation have emerged. One such application is the separati...

  7. Synthesis of fluorinated organic compounds using oxygen difluoride

    NASA Technical Reports Server (NTRS)

    Toy, M. S.

    1971-01-01

    Oxygen difluoride synthesis is a much simpler, higher-yield procedure than reactions originally followed to synthesize various fluorinated organic compounds. Extreme care is taken in working with oxygen difluoride as its reactions present severe explosion hazard.

  8. SEPARATION OF VOLATILE ORGANIC COMPOUNDS FROM SURFACTANT SOLUTIONS BY PERVAPORATION

    EPA Science Inventory

    Pervaporation is gradually becoming an accepted and practical method for the recovery of volatile organic compounds (VOCs) from aqueous process and waste streams. As the technolog has matured, new applications for pervaporation have emerged. One such application is the separati...

  9. SYNTHESIZING ORGANIC COMPOUNDS USING LIGHT-ACTIVATED TIO2

    EPA Science Inventory

    High-value organic compounds have been synthesized successfully from linear and cyclic hydrocarbons, by photocatalytic oxidation using a semiconductor material, titanium dioxide (TiO2). Various hydrocarbons were partially oxgenated in both liquid and gaseous phase reactors usi...

  10. ESTIMATION OF PHYSIOCHEMICAL PROPERTIES OF ORGANIC COMPOUNDS BY SPARC

    EPA Science Inventory

    The computer program SPARC (SPARC Performs Automated Reasoning in Chemistry) has been under development for several years to estimate physical properties and chemical reactivity parameters of organic compounds strictly from molecular structure. SPARC uses computational algorithms...

  11. ESTIMATION OF PHYSIOCHEMICAL PROPERTIES OF ORGANIC COMPOUNDS BY SPARC

    EPA Science Inventory

    The computer program SPARC (SPARC Performs Automated Reasoning in Chemistry) has been under development for several years to estimate physical properties and chemical reactivity parameters of organic compounds strictly from molecular structure. SPARC uses computational algorithms...

  12. Removal of dissolved organic matter in water-hyacinth waste-water treatment lagoons

    SciTech Connect

    Victoria-Rueda, C.H.

    1991-01-01

    Secondary treatment of domestic wastewater in water hyacinth lagoons was evaluated under experimental conditions to assess the role of the roots' bacterial biofilm in the removal of dissolved organic matter (DOM). Research was conducted to (1) quantify removal rates by the biofilm as a function of bulk DOM concentration, (2) formulate an analytical model of DOM removal incorporating biofilm activity, and (3) test the model response to variable organic loads in a pilot-scale plant. Removal of DOM by the biofilm was quantified in continuous-flow water hyacinth tanks at ten concentrations ranging from 45 to 330 g COD m {sup {minus}3} . Total DOM removal in the denitrifying, acetate-based experimental system was measured and partitioned into two fractions associated with the activity of biofilm and suspended bacteria. Calculated DOM removal by the biofilm was adjusted for the release of organic compounds by debris decomposition. Values of DOM removal were used to calculate oxygen transfer rates from the water hyacinth roots. A model of DOM removal in water hyacinth lagoons was formulated. The model, composed of four differential equations, was solved at steady-state conditions and the validity of its simulation results was tested in pilot-scale tanks. Hydraulic detection times ranging from 2 to 28 days were evaluated using biofilm density and concentrations of DOM and particulate organics as monitoring parameters of the model response. The observed decrease of suspended bacterial biomass along the tank was correctly simulated by the model, but predictions of effluent concentrations were not always consistent. Predicted values of biofilm bacterial mass were similar to those measured in the tanks, except when large algal populations were present in the film.

  13. INDOOR AIR QUALITY DATA BASE FOR ORGANIC COMPOUNDS

    EPA Science Inventory

    The report gives results of the compilation of a data base for concentrations of organic compounds measured indoors. ased on a review of the literature from 1979 through 1990, the data base contains information on over 220 compounds ranging in molecular weight from 30 to 446. he ...

  14. INDOOR AIR QUALITY DATA BASE FOR ORGANIC COMPOUNDS

    EPA Science Inventory

    The report gives results of the compilation of a data base for concentrations of organic compounds measured indoors. ased on a review of the literature from 1979 through 1990, the data base contains information on over 220 compounds ranging in molecular weight from 30 to 446. he ...

  15. Speciation of volatile organic compounds from poultry production

    USDA-ARS?s Scientific Manuscript database

    The air consent agreement between EPA and large animal feeding operations (AFO) is designed to determine at what level compounds are being emitted from these facilities. However, the methodology used for quantifying total non-methane hydrocarbons and speciation of volatile organic compounds (VOC) n...

  16. Uptake of organic sulfur and nitrogen compounds by aerosols

    USDA-ARS?s Scientific Manuscript database

    Efforts have been undertaken to monitor and model the uptake of medium-sized organic compounds found above agricultural waste. Field effects performed by our collaborators monitor both the gas phase compounds present in a chicken house in Kentucky; using PILS-IC sampling, the contents of PM2.5 parti...

  17. VOLATILE ORGANIC COMPOUNDS MEASURED IN DEARS PASSIVE SAMPLERS

    EPA Science Inventory

    A suite of 27 volatile organic compounds (VOCs) were monitored in personal exposures, indoors and outdoors of participant's residences, and at a central community site during the DEARS summer 2004 monitoring season. The list of VOCs focused on compounds typically associated with ...

  18. VOLATILE ORGANIC COMPOUNDS MEASURED IN DEARS PASSIVE SAMPLERS

    EPA Science Inventory

    A suite of 27 volatile organic compounds (VOCs) were monitored in personal exposures, indoors and outdoors of participant's residences, and at a central community site during the DEARS summer 2004 monitoring season. The list of VOCs focused on compounds typically associated with ...

  19. Predicting the emission of volatile organic compounds from silage systems

    USDA-ARS?s Scientific Manuscript database

    As a precursor to smog, emission of volatile organic compounds (VOCs) to the atmosphere is an environmental concern in some regions. The major VOC emission source from farms is silage, with emissions coming from the silo face, mixing wagon, and feed bunk. The major compounds emitted are alcohols wit...

  20. Removal of Phenolic Compounds from Water Using Sewage Sludge-Based Activated Carbon Adsorption: A Review.

    PubMed

    Mu'azu, Nuhu Dalhat; Jarrah, Nabeel; Zubair, Mukarram; Alagha, Omar

    2017-09-21

    Due to their industrial relevance, phenolic compounds (PC) are amongst the most common organic pollutants found in many industrial wastewater effluents. The potential detrimental health and environmental impacts of PC necessitate their removal from wastewater to meet regulatory discharge standards to ensure meeting sustainable development goals. In recent decades, one of the promising, cost-effective and environmentally benign techniques for removal of PC from water streams has been adsorption onto sewage sludge (SS)-based activated carbon (SBAC). This is attributed to the excellent adsorptive characteristics of SBAC and also because the approach serves as a strategy for sustainable management of huge quantities of different types of SS that are in continual production globally. This paper reviews conversion of SS into activated carbons and their utilization for the removal of PC from water streams. Wide ranges of topics which include SBAC production processes, physicochemical characteristics of SBAC, factors affecting PC adsorption onto SBAC and their uptake mechanisms as well as the regeneration potential of spent SBAC are covered. Although chemical activation techniques produce better SBAC, yet more research work is needed to harness advances in material science to improve the functional groups and textural properties of SBAC as well as the low performance of physical activation methods. Studies focusing on PC adsorptive performance on SBAC using continuous mode (that are more relevant for industrial applications) in both single and multi-pollutant aqueous systems to cover wide range of PC are needed. Also, the potentials of different techniques for regeneration of spent SBAC used for adsorption of PC need to be assessed in relation to overall economic evaluation within realm of environmental sustainability using life cycle assessment.

  1. Shock Modifications of Organic Compounds in Carbonaceous Chondrite Parent Bodies

    NASA Technical Reports Server (NTRS)

    Cooper, George W.

    1998-01-01

    Impacts among asteroidal objects would have altered or destroyed pre-existing organic matter in both targets and projectiles to a greater or lesser degree depending upon impact velocities. To begin filling a knowledge gap on the shock metamorphism of organic compounds, we are studying the effects of shock impacts on selected classes of organic compounds utilizing laboratory shock facilities. Our approach is to subject mixtures of organic compounds, embedded in the matrix of the Murchison meteorite, to simulated hypervelocity impacts by firing them into targets at various pressures. The mixtures are then analyzed to determine the amount of each compound that survives as well as to determine if new compounds are being synthesized. The initial compounds added to the matrix (with the exception of thiosulfate). The sulfonic acids were chosen in part because they are relatively abundant in Murchison, relatively stable, and because they and the phosphonic acids are the first well-characterized homologous series of organic sulfur and phosphorus compounds identified in an extraterrestrial material. Experimental procedures were more fully described in the original proposal. A 20 mm gun, with its barrel extending into a vacuum chamber (10(exp -2) torr), was used to launch the projectile containing the sample at approx. 1.6 km/sec (3,600 mi/hr) into the target material. Maximum pressure of impact depend on target/projectile materials. The target was sufficiently thin to assure minimum pressure decay over the total sample thickness.

  2. Molecular and Enantiomeric Analysis of Organic Compounds in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Cooper, George

    2003-01-01

    Carbonaceous meteorites are relatively enriched in carbon. Much of this carbon is in the form of soluble organic compounds. The Murchison and Murray meteorites are the best-characterized carbonaceous meteorites with respect to organic chemistry. Their content of organic compounds has led to an initial understanding of early solar system organic chemistry as well as what compounds may have played a role in the origin of life (Cronin and Chang, 1993). Reported compounds include: amino acids, amides, carboxylic acids, sulfonic acids, and polyols. This talk will focus on the molecular and enantiomeric analysis of individual meteoritic compounds: polyol acids; and a newly identified class of meteorite compounds, keto acids, i.e., acetoacetic acid, levulinic acid, etc. Keto acids (including pyruvic) are critically important in all contemporary organisms. They are key intermediates in metabolism and processes such as the citric acid cycle. Using gas chromatography-mass spectrometry we identified individual meteoritic keto acids after derivatization to one or more of the following forms: isopropyl ester (ISP), trimethyIsiIy1 (TMS), tert-butyldimethylsilyl (BDMS). Ongoing analyses will determine if, in addition to certain amino acids from Murchison (Cronin and Pizzarello, 1997), other potentially important prebiotic compounds also contain enantiomeric excesses, i.e., excesses that could have contributed to the current homochirality of life.

  3. Molecular and Enantiomeric Analysis of Organic Compounds in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Cooper, George

    2003-01-01

    Carbonaceous meteorites are relatively enriched in carbon. Much of this carbon is in the form of soluble organic compounds. The Murchison and Murray meteorites are the best-characterized carbonaceous meteorites with respect to organic chemistry. Their content of organic compounds has led to an initial understanding of early solar system organic chemistry as well as what compounds may have played a role in the origin of life (Cronin and Chang, 1993). Reported compounds include: amino acids, amides, carboxylic acids, sulfonic acids, and polyols. This talk will focus on the molecular and enantiomeric analysis of individual meteoritic compounds: polyol acids; and a newly identified class of meteorite compounds, keto acids, i.e., acetoacetic acid, levulinic acid, etc. Keto acids (including pyruvic) are critically important in all contemporary organisms. They are key intermediates in metabolism and processes such as the citric acid cycle. Using gas chromatography-mass spectrometry we identified individual meteoritic keto acids after derivatization to one or more of the following forms: isopropyl ester (ISP), trimethyIsiIy1 (TMS), tert-butyldimethylsilyl (BDMS). Ongoing analyses will determine if, in addition to certain amino acids from Murchison (Cronin and Pizzarello, 1997), other potentially important prebiotic compounds also contain enantiomeric excesses, i.e., excesses that could have contributed to the current homochirality of life.

  4. Process for reducing organic compounds with calcium, amine, and alcohol

    DOEpatents

    Benkeser, R.A.; Laugal, J.A.; Rappa, A.

    1985-08-06

    Olefins are produced by contacting an organic compound having at least one benzene ring with calcium metal, ethylenediamine, a low molecular weight aliphatic alcohol, and optionally a low molecular weight aliphatic primary amine, and/or an inert, abrasive particulate substance. The reduction is conducted at temperatures ranging from about [minus]10 C to about 30 C or somewhat higher. Substantially all of the organic compounds are converted to corresponding cyclic olefins, primarily diolefins.

  5. Process for reducing organic compounds with calcium, amine, and alcohol

    DOEpatents

    Benkeser, Robert A.; Laugal, James A.; Rappa, Angela

    1985-01-01

    Olefins are produced by contacting an organic compound having at least one benzene ring with calcium metal, ethylenediamine, a low molecular weight aliphatic alcohol, and optionally a low molecular weight aliphatic primary amine, and/or an inert, abrasive particulate substance. The reduction is conducted at temperatures ranging from about -10.degree. C. to about 30.degree. C. or somewhat higher. Substantially all of the organic compounds are converted to corresponding cyclic olefins, primarily diolefins.

  6. Remediation of ground water containing volatile organic compounds and tritium

    SciTech Connect

    Shukla, S.N.; Folsom, E.N.

    1994-03-01

    The Trailer 5475 (T-5475) East Taxi Strip Area at Lawrence Livermore National Laboratory (LLNL), Livermore, California was used as a taxi strip by the US Navy to taxi airplanes to the runway from 1942 to 1947. Solvents were used in some unpaved areas adjacent to the East Taxi Strip for cleaning airplanes. From 1953 through 1976, the area was used to store and treat liquid waste. From 1962 to 1976 ponds were constructed and used for evaporation of liquid waste. As a result, the ground water in this area contains volatile organic compounds (VOCs) and tritium. The ground water in this area is also known to contain hexavalent chromium that is probably naturally occurring. Therefore, LLNL has proposed ``pump-and-treat`` technology above grade in a completely closed loop system. The facility will be designed to remove the VOCs and hexavalent chromium, if any, from the ground water, and the treated ground water containing tritium will be reinjected where it will decay naturally in the subsurface. Ground water containing tritium will be reinjected into areas with equal or higher tritium concentrations to comply with California regulations.

  7. Size fractionation characterisation of removed organics in reverse osmosis concentrates by ferric chloride.

    PubMed

    Bagastyo, A Y; Keller, J; Batstone, D J

    2011-01-01

    Reverse osmosis membrane separation is the leading method for manufacturing potable purified water. It also produces a concentrate stream, namely reverse osmosis concentrates (ROC), with 10-20% of the water, and almost all other compounds. One method for further treating this stream is by coagulation with ferric chloride. This study evaluates removed organics in ROC treated with ferric chloride. Fractionation with ultrafiltration membranes allows separation of organics based on a nominal molecular weight. A stirred cell system was applied for serial fractionation to classify organic compounds into six groups of < 0.5 kDa, 0.5-1 kDa, 1-3 kDa, 3-5 kDa, 5-10 kDa and > 10 kDa. The study found that raw ROC is rich in low molecular weight compounds (< 1 kDa) with almost 50% of the organics. These compounds include soluble microbial products (SMPs) and smaller humic and fulvic acids as indicated by fluorescence scanning. Conversely, colour was mostly contributed by medium to large molecules of humic and fulvic acids (> 0.5 kDa). Organics and colour were reduced in all molecular groups at an optimum treatment dose 1.48 mM FeCl3 and a pH of 5. However, ferric seemed to effectively remove colour in all size ranges while residual nitrogen was found mostly in the < 1 kDa sizes. Further, the fluorescence indicated that larger humic and fulvic acids were removed with considerable SMPs remaining in the < 0.5 kDa.

  8. Evaluation of control strategies for volatile organic compounds in indoor air (journal article)

    SciTech Connect

    Ramanathan, K.; Debler, V.L.

    1988-01-01

    The paper discusses research which evaluates the application of adsorption techniques to the control of indoor organic vapors. The adsorption on activated carbon of three compounds representing three classes of organic species was studied at 30 C in the concentration range zero to 200 ppb using a microbalance. The three were benzene (aromatic), acetaldehyde (oxygenated aliphatic), and 1,1,1-trichloroethane (halogenated aliphatic). Three sorbents (a wood base carbon, a coal base carbon, and a coconut shell base carbon) were examined. Uptakes for all the compounds on all the carbons were low (on the order of 10 to the minus 7th power gmol/g carbon). Simulation of a packed bed of carbon indicated that carbon adsorption may not be practical for continuous removal, but may be applicable to sudden releases (e.g., spills). Potential alternatives to activated carbon adsorption are discussed. Potentially toxic organic vapors are emitted from a wide variety of building materials, consumer products, and human activities. Control of indoor organic vapors generally involves removing the source and/or increasing the ventilation rate. The ubiquitous nature of sources of organic vapors generally makes source removal impractical. Increased ventilation causes increased energy usage with its resultant economic penalties. Therefore, practical removal methods are needed.

  9. A human rights approach to human trafficking for organ removal.

    PubMed

    Budiani-Saberi, Debra; Columb, Seán

    2013-11-01

    Human trafficking for organ removal (HTOR) should not be reduced to a problem of supply and demand of organs for transplantation, a problem of organized crime and criminal justice, or a problem of voiceless, abandoned victims. Rather, HTOR is at once an egregious human rights abuse and a form of human trafficking. As such, it demands a human-rights based approach in analysis and response to this problem, placing the victim at the center of initiatives to combat this phenomenon. Such an approach requires us to consider how various measures impact or disregard victims/potential victims of HTOR and gives us tools to better advocate their interests, rights and freedoms.

  10. Removing environmental organic pollutants with bioremediation and phytoremediation.

    PubMed

    Kang, Jun Won

    2014-06-01

    Hazardous organic pollutants represent a threat to human, animal, and environmental health. If left unmanaged, these pollutants could cause concern. Many researchers have stepped up efforts to find more sustainable and cost-effective alternatives to using hazardous chemicals and treatments to remove existing harmful pollutants. Environmental biotechnology, such as bioremediation and phytoremediation, is a promising field that utilizes natural resources including microbes and plants to eliminate toxic organic contaminants. This technology offers an attractive alternative to other conventional remediation processes because of its relatively low cost and environmentally-friendly method. This review discusses current biological technologies for the removal of organic contaminants, including chlorinated hydrocarbons, focusing on their limitation and recent efforts to correct the drawbacks.

  11. Removal of cyanide compounds from coking wastewater by ferrous sulfate: Improvement of biodegradability.

    PubMed

    Yu, Xubiao; Xu, Ronghua; Wei, Chaohai; Wu, Haizhen

    2016-01-25

    The effect of ferrous sulfate (FeSO4) treatment on the removal of cyanide compounds and the improvement of biodegradability of coking wastewater were investigated by varying Fe:TCN molar ratios. Results suggested that the reaction between FeSO4 and coking wastewater was a two-step process. At the first step, i.e., 0≤Fe:TCN≤1.0, the reaction mechanisms were dominated by the precipitation of FeS, the complexation of CN(-), and the coagulation of organic compounds. The COD of coking wastewater decreased from 3748.1 mg/L to 3450.2 mg/L, but BOD5:COD (B/C) was improved from 0.30 to 0.51. At the second step, i.e., 1.0compounds by ferrous ions was the dominating mechanism. The COD showed a continuous increase to 3542.2 mg/L (Fe:TCN=3.2) due to the accumulated ferrous ions in coking wastewater. Moreover, B/C decreased progressively to 0.35, which was attributed to the negative effects of excess ferrous ions on biodegradability. To improve coking wastewater's biodegradability, a minimum ferrous dosage is required to complete the first step reaction. However, the optimum ferrous dosage should be determined to control a safe residual TCN in coking wastewater for the further biological treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Effect of sequential removal of organic matter on the surface morphology of humin

    SciTech Connect

    Malekani, K.; Rice, J.A.; Lin, Jar-Shyong

    1997-05-01

    Natural organic matter in soils interacts with surfaces of inorganic materials, primarily aluminosilicates or clay minerals, to form a strongly associated organo-mineral composite known as humin. Because of humin`s insolubility, it is recognized as the primary sorbent of many anthropogenic organic compounds (AOCs) introduced into soil systems. This recognition has significant implications for understanding the fate and transport of AOCs, the effective remediation of contaminated sites, and the formulation and application of various agrochemicals. Humin was isolated from four soil samples. Surface area, surface charge, porosity measurements, and fractal analysis of small-angle X-ray scattering data were used to characterize changes in the surface properties resulting from selective removal of the various components of organic matter from humin. Organic matter was removed selectively from humin by Soxhlet extraction, disaggregation with the methylisobutylketone (MIBK) method, and bromine oxidation. The surface fractal dimensions decreased while surface area increased, and surface pore size decreased upon removal of organic matter. These results suggest that the mineral components of humin have smooth surfaces over length scales of {approximately}1 to 15 run, and that it is the organic matter coatings that are responsible for their surface roughness. The surfaces of all the components of humin were found to be dominated by micro and mesopores that could be responsible for humin`s high sorptive uptake of organic chemicals.

  13. The Effect of Golden Pothos in Reducing the Level of Volatile Organic Compounds in a Simulated Spacecraft Cabin

    NASA Technical Reports Server (NTRS)

    Ursprung, Matthew; Amiri, Azita; Kayatin, Matthew; Perry, Jay

    2016-01-01

    The impact of Golden Pothos on indoor air quality was studied against a simulated spacecraft trace contaminant load model, consistent with the International Space Station (ISS), containing volatile organic compounds (VOCs) and formaldehyde. Previous research provides inconclusive results on the efficacy of plant VOC removal which this projects seeks to rectify through a better experimental design. This work develops a passive system for removing common VOC's from spacecraft and household indoor air and decreasing the necessity for active cabin trace contaminant removal systems.

  14. Laser-induced removal of organic contaminants from metal substrates

    NASA Astrophysics Data System (ADS)

    Song, Wen D.; Lu, Yongfeng; Chen, Q.; Low, Tohsiew

    1998-08-01

    Laser-induced removal of organic contaminants, such as grease and wax, on Cr substrate surfaces was studied. The laser cleaning efficiency was analyzed by an optical microscope and an Auger Electron Spectroscopy (AES). It was found that the contaminants in the irradiated area can be effectively removed by pulsed laser irradiation and cleaning efficiency can be reached to 80% above under a certain cleaning condition without damage. The damage threshold of Cr substrates was obtained by numerical simulation, which is in good consistency with the experimental threshold.

  15. Device for removing foreign objects from anatomic organs

    NASA Technical Reports Server (NTRS)

    Angulo, Earl D. (Inventor)

    1992-01-01

    A device is disclosed for removing foreign objects from anatomic organs such as the ear canal or throat. It has a housing shaped like a flashlight, an electrical power source such as a battery or AC power from a wall socket, and a tip extending from the housing. The tip has at least one wire loop made from a shape-memory-effect alloy, such as Nitinol, switchably connected to the electrical power source such that when electric current flows through the wire loop the wire loop heats up and returns to a previously programmed shape such as a curet or tweezers so as to facilitate removal of the foreign object.

  16. Dissolution, Cyclodextrin-Enhanced Solubilization, and Mass Removal of an Ideal Multicomponent Organic Liquid

    PubMed Central

    Carroll, Kenneth C.; Brusseau, Mark L.

    2010-01-01

    Laboratory experiments and mathematical modeling were conducted to examine the influence of a hydroxypropyl-beta-cyclodextrin (HPCD) solution on the dissolution of single- and three-component organic liquids. The results of batch experiments showed that HPCD-enhanced solubilization of the organic-liquid mixtures was ideal (describable using Raoult’s Law), and that solubilization-enhancement factors were independent of mixture composition. Addition of the HPCD solution to columns containing residual saturations of the organic liquid enhanced the dissolution and removal of all three compounds in the mixture. The results of the column experiments and multicomponent rate-limited dissolution modeling suggest that solubilization was ideal for both water and cyclodextrin flushing. Concomitantly, the mass-flux reduction versus mass removal behavior was ideal for all experiments. Mass transfer was increased for HPCD solubilization relative to the water flushing due to solubility and concentration-gradient enhancement. Organic-liquid composition did not significantly impact mass transfer coefficients, and fractional mass removal behavior during HPCD solubilization was nearly identical for each compound whether present as a single component or in a mixture. Additionally, mass transfer coefficients for aqueous and HPCD solubilization for single and multicomponent mixtures were not statistically different upon normalizing by the solubility enhancement factor. PMID:19233508

  17. Transport, behavior, and fate of volatile organic compounds in streams

    USGS Publications Warehouse

    Rathbun, R.E.

    1998-01-01

    Volatile organic compounds (VOCs) are compounds with chemical and physical properties that allow the compounds to move freely between the water and air phases of the environment. VOCs are widespread in the environment because of this mobility. Many VOCs have properties making them suspected or known hazards to the health of humans and aquatic organisms. Consequently, understanding the processes affecting the concentration and distribution VOCs in the environment is necessary. The U.S. Geological Survey selected 55 VOCs for study. This report reviews the characteristics of the various process that could affect the transport, behavior, and fate of these VOCs in streams.

  18. Geosynthesis of organic compounds: I. Alkylphenols

    NASA Astrophysics Data System (ADS)

    Ioppolo-Armanios, Marisa; Alexander, Robert; Kagi, Robert I.

    1995-07-01

    Methylation, isopropylation, and sec-butylation are proposed as geosynthetic processes to account for the alkylphenol compositions of crude oils with phenol distributions dominated by ortho and para substituted compounds. Phenol distributions in eleven crude oils and four kerogen pyrolysates were analysed using GC-MS (gas chromatography-mass spectrometry). Ten of the crude oils show high relative abundances of ortho and para substituted phenol isomers and some were also enriched in C 3-C 5 alkylphenols compared to the kerogen pyrolysates. Because the distributions of products obtained from the laboratory alkylation of cresols closely resemble those of phenols in these crude oils, we propose that similar alkylation processes occur in source rocks. Alkylation ratios reflecting the degree of methylation, isopropylation, and sec-butylation, which were based on the relative abundance of the dominant alkylation products compared to their likely precursor ortho-cresol, indicate that high levels of methylation occurred in crude oils over a wide range of maturities, whereas high levels of isopropylation and sec-butylation were observed only in mature samples. Dissolution of the phenols in crude oils by water contact was discounted as an explanation for the observed phenol distributions based on the relative distribution coefficients of phenols between a hydrocarbon phase and water.

  19. Removal characteristics of trace compounds of landfill gas by activated carbon adsorption.

    PubMed

    Shin, Ho-Chul; Park, Jin-Won; Park, Kwinam; Song, Ho-Cheol

    2002-01-01

    The removal characteristics of trace compounds and moisture in raw landfill gas (LFG) were studied. The LFG from the extraction well was saturated with water and moisture was eliminated by physical methods including cyclone-type dehydrator and compressor. The moisture removal efficiency of dehydrator and compressor was above 80%. As the moisture contents of LFG decreased, the toxic compounds like aromatics and chlorinated compounds were effectively removed by using the granular activated carbon. The breakthrough time and adsorption capacity of benzene, toluene, and ethyl benzene decreased rapidly when the relative humidity is over 60%. The effect of moisture was more pronounced at lower adsorbate concentrations tested than at higher concentrations. The breakthrough curves for multi-component mixtures show displacement effects. In the course of competing adsorption, adsorbates with strong interaction force to displace weakly bounded substances. Adsorption by activated carbon is in descending order of xylene, ethylbenzene, toluene, tri or tetrachloroethylene, benzene, carbon tetrachloride and chloroform in LFG, respectively.

  20. Removals of pharmaceutical compounds from hospital wastewater in membrane bioreactor operated under short hydraulic retention time.

    PubMed

    Prasertkulsak, S; Chiemchaisri, C; Chiemchaisri, W; Itonaga, T; Yamamoto, K

    2016-05-01

    Pilot-scale membrane bioreactor (MBR) was operated at a short hydraulic retention time (HRT) of 3 h for the treatment of hospital wastewater. The removals of eleven pharmaceutical compounds in MBR operated at different mixed liquor suspended solids (MLSS) level were investigated during which nitrification degree was differed. The results experiments revealed the importance of immediate adsorption onto the colloidal particles in supernatant of MBR sludge and subsequently removed by membrane filtration for the recalcitrant pharmaceutical compounds. Nevertheless, the removals through biodegradation during short HRT were also found significant for some compounds. DGGE profile revealed the development of pharmaceutical degrading microorganisms in MBR. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Polar organic solvent removal in microcosm constructed wetlands.

    PubMed

    Grove, Janet Kowles; Stein, Otto R

    2005-10-01

    Three polar organic solvents, acetone, tetrahydrofuran (THF) and 1-butanol, were added at 100 mg/l each to post-primary municipal wastewater in order to simulate a mixed waste stream. This mixture was applied to an experimental microcosm subsurface constructed wetland system consisting of replicates of Juncus effusus, Carex lurida, Iris pseudacorus, Pondeteria cordata and unplanted controls in a series of 14-day batch incubations over a yearlong period simulating a summer and winter season. 90% removal of 1-butanol typically took less than 3 days. 90% removal of acetone required from 5 to 10 days in summer and 10 to 14 days in winter. 90% removal of THF required at least 10 days and was frequently not achieved during the 14-day incubations. Initial experiments confirmed that the majority of solvent removal was via microbial bioremediation. Solvent removal was typically better in planted replicates, especially Juncus, regardless of season. The removal rate of all solvents was slower in winter, but the seasonal effect was most pronounced in the unplanted control replicates and least in the Carex and Juncus replicates. Plant and seasonal effects are believed to be due, in part, to variation in metabolic pathways induced by plant and seasonal variation in available root-zone oxygen. Variation in transpiration also influenced species and seasonal effects on THF removal, but not the other more biodegradable solvents. A model based on a prediction of plant uptake of nonionic dissolved chemicals suggests that as much as 39% of the THF in solution could have been removed through plant transpiration.

  2. Typical low cost biosorbents for adsorptive removal of specific organic pollutants from water.

    PubMed

    Tran, Van Son; Ngo, Huu Hao; Guo, Wenshan; Zhang, Jian; Liang, Shuang; Ton-That, Cuong; Zhang, Xinbo

    2015-04-01

    Specific organic pollutants (SOPs) such as phenolic compounds, PAHs, organic pesticides, and organic herbicides cause health and environmental problems due to their excessive toxic properties and poor biodegradability. Low-cost biosorbents are considered as a promising alternative for conventional adsorbents to remove SOPs from water. These materials have several advantages such as high sorption capacities, good modifiability and recoverability, insensitivity to toxic substances, simple operation in the treatment processes. However, previous reports on various types of biosorbents for removing SOPs are still moderately fragmented. Hence, this paper provides a comprehensive review on using typical low-cost biosorbents obtained from lignocellulose and chitin/chitosan for SOPs adsorption. Especially, their characteristics, biosorption mechanism together with utilization for eliminating SOPs are presented and discussed. The paper also gives a critical view regarding future applications of low-cost biosorbents in SOPs-contaminated water treatment.

  3. Analysis of volatile organic compounds from illicit cocaine samples

    SciTech Connect

    Robins, W.H.; Wright, B.W.

    1994-07-01

    Detection of illicit cocaine hydrochloride shipments can be improved if there is a greater understanding of the identity and quantity of volatile compounds present. This study provides preliminary data concerning the volatile organic compounds detected in a limited Set of cocaine hydrochloride samples. In all cases, cocaine was one of the major volatile compounds detected. Other tropeines were detected in almost all samples. Low concentrations of compounds that may be residues of processing solvents were observed in some samples. The equilibrium emissivity of. cocaine from cocaine hydrochloride was investigated and a value of 83 parts-per-trillion was determined.

  4. Rejection of trace organic compounds by high-pressure membranes.

    PubMed

    Kim, T U; Amy, G; Drewes, J E

    2005-01-01

    High-pressure membranes, encompassing reverse osmosis (RO), nanofiltration (NF), and low-pressure RO, may provide an effective treatment barrier for trace organic compounds including disinfection by-products (DBPs), pesticides, solvents, endocrine disrupting compounds (EDCs) and pharmaceutically active compounds (PhACs). The objective is to develop a mechanistic understanding of the rejection of trace organic compounds by high-pressure membranes, based on an integrated framework of compound properties, membrane properties, and operational conditions. Eight trace organic compounds, four DBPs and four chlorinated (halogenated) solvents, are being emphasized during an initial study, based on considerations of compound properties, occurrence, and health effects (regulations). Four polyamide FilmTec membranes; three reverse osmosis/RO (BW-400, LE-440, XLE-440) and one nanofiltration/NF (NF-90); are being characterized according to pure water permeability (PWP), molecular weight cutoff (MWCO), hydrophobicity (contact angle), and surface charge (zeta potential). It is noteworthy that rejections of compounds of intermediate hydrophobicity by the candidate membranes were observed to be less than salt rejections reported for these membranes, suggesting that transport of these solutes through these membranes is facilitated by solute-membrane interactions. We are continuing with diffusion cell measurements to describe solute-membrane interactions by estimation of diffusion coefficients through membranes pores, either hindered or facilitated.

  5. Comparison of treatment options for removal of recalcitrant dissolved organic matter from paper mill effluent.

    PubMed

    Ciputra, Sandra; Antony, Alice; Phillips, Ross; Richardson, Des; Leslie, Greg

    2010-09-01

    Recycling paper mill effluent by conventional water treatment is difficult due to the persistence of salt and recalcitrant organics. Elimination of dissolved organic matter (DOM) from paper mill effluent was studied using three treatment options, ion exchange resin (IER), granular activated carbon (GAC) and nanofiltration (NF). The removal efficiency was analysed based on hydrophobicity, molecular weight and fluorogenic origin of the DOM fractions. For IER, GAC and NF treatments, overall removal of dissolved organic carbon was 72%, 76% and 91%, respectively. Based on the hydrophobicity, all the three treatment methods majorly removed hydrophobic acid fractions (HPhoA). Further, IER acted on all fractions, 57% of HPhoA, 44% of transphilic acid and 18% of hydrophilics, substantiating that the removal is by both ion exchange and adsorption. Based on the molecular weight, IER and GAC treatments acted majorly on the high molecular weight fractions, whereas NF eliminated all molecular weight fractions. After GAC adsorption, some amount of humic hydrolysates and low molecular weight neutrals persisted in the effluent. After IER treatment, amount of low molecular weight compounds increased due to resin leaching. Qualitative analysis of fluorescence excitation emission matrices showed that the fulvic acid-like fluorophores were more recalcitrant among the various DOM fractions, considerable amount persisted after all the three treatment methods. Three treatment methods considerably differed in terms of removing different DOM fractions; however, a broad-spectrum process like NF would be needed to achieve the maximum elimination. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  6. Recent advances in trifluoromethylation of organic compounds using Umemoto's reagents.

    PubMed

    Zhang, Cai

    2014-09-14

    The incorporation of fluorine-containing moieties into organic compounds is of great importance in pharmaceutical, agricultural, and materials science. Within these organofluorides, the trifluoromethyl group is one of the most important motifs. In recent years, the trifluoromethyl group has attracted more and more attention, and many trifluoromethylated compounds have been found to possess special activities. However, until now, only a few methods have been developed to achieve this efficiently using Umemoto's reagents. This review highlights recent developments in the direct introduction of a trifluoromethyl group into organic compounds with Umemoto's reagents. Seven approaches to the trifluoromethylation of organic compounds are summarized: (i) trifluoromethylation of arenes, (ii) trifluoromethylation of alkenes, (iii) trifluoromethylation of terminal alkynes, (iv) deoxygenative trifluoromethylation of benzylic xanthates, (v) trifluoromethylation of ketoesters, (vi) trifluoromethylation of aryl boronic acids and aromatic amines (synthesis of ArCF3) and (vii) trifluoromethylation of biphenyl isocyanide derivatives.

  7. Characterizations of organic compounds in diesel exhaust particulates.

    PubMed

    Lim, Jaehyun; Lim, Cheolsoo; Kim, Sangkyun; Hong, Jihyung

    2015-08-01

    To characterize how the speed and load of a medium-duty diesel engine affected the organic compounds in diesel particle matter (PM) below 1 μm, four driving conditions were examined. At all four driving conditions, concentration of identifiable organic compounds in PM ultrafine (34-94 nm) and accumulation (94-1000 nm) modes ranged from 2.9 to 5.7 μg/m(3) and 9.5 to 16.4 μg/m(3), respectively. As a function of driving conditions, the non-oxygen-containing organics exhibited a reversed concentration trend to the oxygen-containing organics. The identified organic compounds were classified into eleven classes: alkanes, alkenes, alkynes, aromatic hydrocarbons, carboxylic acids, esters, ketones, alcohols, ethers, nitrogen-containing compounds, and sulfur-containing compounds. At all driving conditions, alkane class consistently showed the highest concentration (8.3 to 18.0 μg/m(3)) followed by carboxylic acid, esters, ketones and alcohols. Twelve polycyclic aromatic hydrocarbons (PAHs) were identified with a total concentration ranging from 37.9 to 174.8 ng/m(3). In addition, nine nitrogen-containing polycyclic aromatic compounds (NPACs) were identified with a total concentration ranging from 7.0 to 10.3 ng/m(3). The most abundant PAH (phenanthrene) and NPACs (7,8-benzoquinoline and 3-nitrophenanthrene) comprise a similar molecular (3 aromatic-ring) structure under the highest engine speed and engine load.

  8. Predicting crystal structures of organic compounds.

    PubMed

    Price, Sarah L

    2014-04-07

    Currently, organic crystal structure prediction (CSP) methods are based on searching for the most thermodynamically stable crystal structure, making various approximations in evaluating the crystal energy. The most stable (global minimum) structure provides a prediction of an experimental crystal structure. However, depending on the specific molecule, there may be other structures which are very close in energy. In this case, the other structures on the crystal energy landscape may be polymorphs, components of static or dynamic disorder in observed structures, or there may be no route to nucleating and growing these structures. A major reason for performing CSP studies is as a complement to solid form screening to see which alternative packings to the known polymorphs are thermodynamically feasible.

  9. Scaffold of Asymmetric Organic Compounds - Magnetite Plaquettes

    NASA Technical Reports Server (NTRS)

    Chan, Q. H. S.; Zolensky, M. E.; Martinez, J.

    2015-01-01

    Life on Earth shows preference towards the set of organics with particular spatial configurations, this 'selectivity' is a crucial criterion for life. With only rare exceptions, life prefers the left- (L-) form over the right- (D-) form of amino acids, resulting in an L-enantiomeric excess (L-ee). Recent studies have shown Lee for alpha-methyl amino acids in some chondrites. Since these amino acids have limited terrestrial occurrence, the origin of their stereoselectivity is nonbiological, and it seems appropriate to conclude that chiral asymmetry, the molecular characteristic that is common to all terrestrial life form, has an abiotic origin. A possible abiotic mechanism that can produce chiral asymmetry in meteoritic amino acids is their formation with the presence of asymmetric catalysts, as mineral crystallization can produce spatially asymmetric structures. Magnetite is shown to be an effective catalyst for the formation of amino acids that are commonly found in chondrites. Magnetite 'plaquettes' (or 'platelets'), first described by Jedwab, show an interesting morphology of barrel-shaped stacks of magnetite disks with an apparent dislocation-induced spiral growth that seem to be connected at the center. A recent study by Singh et al. has shown that magnetites can self-assemble into helical superstructures. Such molecular asymmetry could be inherited by adsorbed organic molecules. In order to understand the distribution of 'spiral' magnetites in different meteorite classes, as well as to investigate their apparent spiral configurations and possible correlation to molecular asymmetry, we observed polished sections of carbonaceous chondrites (CC) using scanning electron microscope (SEM) imaging. The sections were also studied by electron backscattered diffraction (EBSD) in order to reconstruct the crystal orientation along the stack of magnetite disks.

  10. Investigating the removal of some pharmaceutical compounds in hospital wastewater treatment plants operating in Saudi Arabia.

    PubMed

    Al Qarni, Hamed; Collier, Philip; O'Keeffe, Juliette; Akunna, Joseph

    2016-07-01

    The concentrations of 12 pharmaceutical compounds (atenolol, erythromycin, cyclophosphamide, paracetamol, bezafibrate, carbamazepine, ciprofloxacin, caffeine, clarithromycin, lidocaine, sulfamethoxazole and N-acetylsulfamethoxazol (NACS)) were investigated in the influents and effluents of two hospital wastewater treatment plants (HWWTPs) in Saudi Arabia. The majority of the target analytes were detected in the influent samples apart from bezafibrate, cyclophosphamide, and erythromycin. Caffeine and paracetamol were detected in the influent at particularly high concentrations up to 75 and 12 ug/L, respectively. High removal efficiencies of the pharmaceutical compounds were observed in both HWWTPs, with greater than 90 % removal on average. Paracetamol, sulfamethoxazole, NACS, ciprofloxacin, and caffeine were eliminated by between >95 and >99 % on average. Atenolol, carbamazepine, and clarithromycin were eliminated by >86 % on average. Of particular interest were the high removal efficiencies of carbamazepine and antibiotics that were achieved by the HWWTPs; these compounds have been reported to be relatively recalcitrant to biological treatment and are generally only partially removed. Elevated temperatures and high levels of sunlight were considered to be the main factors that enhanced the removal of these compounds.

  11. Biofiltration of odors, toxics and volatile organic compounds from publicly owned treatment works

    SciTech Connect

    Webster, T.S.; Devinny, J.S.; Torres, E.M.; Basrai, S.S.

    1996-12-31

    Increasing federal and state regulation has made it necessary to apply air pollution control measures at publicly owned treatment works (POTWs). Traditional control technologies may not be suitable for treating the low and variable contaminant concentrations often found in POTW off-gases. An alternative control technology, biofiltration, was studied. An experiment using bench- and pilot-scale reactors established optimal operating conditions for a full-scale conceptual design. The waste airstream contained ppmv levels of hydrogen sulfide and ppbv levels of specific volatile organic compounds (VOCs). Granular activated carbon (GAC) and yard waste compost (YWG) were tested as possible biofilter media with and without pH control. The 16-month field study bench reactors achieved 99% removal of hydrogen sulfide, 53 to 98% removal of aromatic hydrocarbons, 37 to 95% removal of aldehydes and ketones, and 0 to 85% removal of chlorinated compounds. The GAC and YWC pilot reactors removed more than 80% and 65% of the total VOCs at 17 second and 70 second empty bed retention times, respectively. The YWC reactors performed poorly at empty bed retention times of 30 and 45 seconds, removing less than 40% of total VOCs. Declining pH had little negative effect on contaminant removal, suggesting costly control measures may not be necessary. Biofiltration appears to be a feasible alternative to traditional control technologies in treating off-gases from POTWs. 13 refs., 3 figs., 4 tabs.

  12. Use of sonication for in-well softening of semivolatile organic compounds. 1997 annual progress report

    SciTech Connect

    Peters, R.W.; Manning, J.; Hoffman, M.R.; Gorelick, S.

    1997-01-01

    'This project investigates the in-situ degradation of semivolatile organic compounds (SVOCs) and volatile organic compounds (VOCs) using in-well sonication, in-well vapor stripping, and bioremediation. Pretreating groundwaters with sonication techniques in-situ would form VOCs that can be effectively removed by in-well vapor stripping and bioremediation. The mechanistic studies focus on the coupling of megasonics and ultrasonics to soften (i.e., partially degrade) the SVOCs; oxidative reaction mechanism studies; surface corrosion studies (on the reactor walls/well); enhancement due to addition of oxidants, quantification of the hydroxyl radical formation; identification/quantification of degradation products; volatility/degradability of the treated waters; development of a computer simulation model to describe combined in-well sonication/in-well vapor stripping/bioremediation; systems analysis/economic analysis; large laboratory-scale experiment verification; and field demonstration of the integrated technology. Benefits of this approach include: (1) Remediation is performed in-situ; (2) The treatment systems complement each other; their combination can drastically reduce or remove SVOCs and VOCs; (3) Ability to convert hard-to-degrade organics into more volatile organic compounds; (4) Ability to remove residual VOCs and softened SVOCs through the combined action of in-well vapor stripping and biodegradation; (5) Does not require handling or disposing of water at the ground surface; and (6) Cost-effective and improved efficiency, resulting in shortened clean-up times to remediate a site.'

  13. USE OF SONICATION FOR IN-WELL SOFTENING OF SEMIVOLATILE ORGANIC COMPOUNDS

    SciTech Connect

    Peters, Robert W.

    2000-12-31

    This project investigates the in-situ degradation of semivolatile organic compounds (SVOCs) and volatile organic compounds (VOCs) using in-well sonication, in-well vapor stripping, and bioremediation. Pretreating groundwaters with sonication techniques in-situ would form VOCs that can be effectively removed by in-well vapor stripping and bioremediation. The mechanistic studies focus on the coupling of megasonics and ultrasonics to ''soften'' (i.e., partially degrade) the SVOCs; oxidative reaction mechanism studies; surface corrosion studies (on the reactor walls/well); enhancement due to addition of oxidants, quantification of the hydroxyl radical formation; identification/quantification of degradation products; volatility/degradability of the treated waters; development of a computer simulation model to describe combined in-well sonication/in-well vapor stripping/bioremediation; systems analysis/economic analysis; large laboratory-scale experiment verification; and field demonstration of the integrated technology. Benefits of this approach include: (1) Remediation is performed in-situ; (2) The treatment systems complement each other; their combination can drastically reduce or remove SVOCs and VOCs; (3) Ability to convert hard-to-degrade organics into more volatile organic compounds; (4) Ability to remove residual VOCs and ''softened'' SVOCs through the combined action of in-well vapor stripping and biodegradation; (5) Does not require handling or disposing of water at the ground surface; and (6) Cost-effective and improved efficiency, resulting in shortened clean-up times to remediate a site.

  14. Volatile and semivolatile organic compounds in laboratory peat fire emissions

    EPA Science Inventory

    Speciated volatile organic compounds (VOCs) and organic fine particulate matter (PM2.5) mass emission factors were determined from laboratory peat fire experiments. Peat samples originated from two wildlife reserves located near the coast of North Carolina, U.S. Gas and particula...

  15. Origins, fates, and ramifications of natural organic compounds of wetlands

    Treesearch

    Robert G. Wetzel

    2000-01-01

    Much of the organic carbon for heterotrophic metabolism in aquatic ecosystems is soluble and derived from structural compounds of higher plants of terrestrial and wetland-littoral sources of both lake and river ecosystems. The chemical recalcitrance of this organic matter and its oxidative utilization are fundamentally different from many sources within the aquatic...

  16. INTERACTIONS BETWEEN ORGANIC COMPOUNDS AND CYCLODEXTRIN-CLAY SYSTEMS

    EPA Science Inventory

    Computational and experimental techniques are combined in order to better understand interactions involving organic compounds and cyclodextrin (CD)-clay systems. CD-clay systems may have great potential in the containment of organic contaminants in the environment. This study w...

  17. Volatile and semivolatile organic compounds in laboratory peat fire emissions

    EPA Science Inventory

    Speciated volatile organic compounds (VOCs) and organic fine particulate matter (PM2.5) mass emission factors were determined from laboratory peat fire experiments. Peat samples originated from two wildlife reserves located near the coast of North Carolina, U.S. Gas and particula...

  18. INTERACTIONS BETWEEN ORGANIC COMPOUNDS AND CYCLODEXTRIN-CLAY SYSTEMS

    EPA Science Inventory

    Computational and experimental techniques are combined in order to better understand interactions involving organic compounds and cyclodextrin (CD)-clay systems. CD-clay systems may have great potential in the containment of organic contaminants in the environment. This study w...

  19. LOSS OF ORGANIC CHEMICALS IN SOIL: PURE COMPOUND TREATABILITY STUDIES

    EPA Science Inventory

    Comprehensive screening data on the treatability of 32 organic chemicals in soil were developed. Of the evaluated chemicals, 22 were phenolic compounds. Aerobic batch laboratory microcosm experiments were conducted using two soils: an acidic clay soil with <1% organic matter and ...

  20. 40 CFR 60.392 - Standards for volatile organic compounds

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards for volatile organic compounds 60.392 Section 60.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Automobile and Light Duty Truck Surface Coating Operations § 60.392 Standards for volatile organic...

  1. 40 CFR 60.392 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards for volatile organic compounds. 60.392 Section 60.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Automobile and Light Duty Truck Surface Coating Operations § 60.392 Standards for volatile organic...

  2. 40 CFR 60.392 - Standards for volatile organic compounds

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards for volatile organic compounds 60.392 Section 60.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Automobile and Light Duty Truck Surface Coating Operations § 60.392 Standards for volatile organic...

  3. 40 CFR 60.432 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.432 Section 60.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Graphic Arts Industry: Publication Rotogravure Printing § 60.432 Standard for volatile organic...

  4. 40 CFR 60.392 - Standards for volatile organic compounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.392 Section 60.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Automobile and Light Duty Truck Surface Coating Operations § 60.392 Standards for volatile organic...

  5. 40 CFR 60.432 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for volatile organic compounds. 60.432 Section 60.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Graphic Arts Industry: Publication Rotogravure Printing § 60.432 Standard for volatile organic...

  6. 40 CFR 60.432 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for volatile organic compounds. 60.432 Section 60.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Graphic Arts Industry: Publication Rotogravure Printing § 60.432 Standard for volatile organic...

  7. 40 CFR 60.432 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for volatile organic compounds. 60.432 Section 60.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Graphic Arts Industry: Publication Rotogravure Printing § 60.432 Standard for volatile organic...

  8. 40 CFR 60.432 - Standard for volatile organic compounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for volatile organic compounds. 60.432 Section 60.432 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Graphic Arts Industry: Publication Rotogravure Printing § 60.432 Standard for volatile organic...

  9. 40 CFR 60.392 - Standards for volatile organic compounds

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for volatile organic compounds 60.392 Section 60.392 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Automobile and Light Duty Truck Surface Coating Operations § 60.392 Standards for volatile organic...

  10. Students' Understanding of Molecular Structure and Properties of Organic Compounds.

    ERIC Educational Resources Information Center

    Schmidt, Hans-Jurgen

    The purpose of this study was to investigate senior high school students' difficulties predicting the existence of hydrogen bridge bonds between organic molecules, investigate students' difficulties predicting the relative boiling points of simple organic compounds, and develop test questions that enable teachers to quickly get information about…

  11. BIOCONCENTRATION FACTORS FOR VOLATILE ORGANIC COMPOUNDS IN VEGETATION

    EPA Science Inventory

    Samples of air and leaves were taken at the University of Nevada-Las Vegas campus and analyzed for volatile organic compounds using vacuum distillation coupled with gas chromatography/mass spectrometry. The data were used to estimate the bioconcentration of volatile organic compo...

  12. Leveraging the beneficial compounds of organic and pasture milk

    USDA-ARS?s Scientific Manuscript database

    Much discussion has arisen over the possible benefits of organic food, including milk. Organic milk comes from cows that are on pasture during the growing season, and would be expected to contain some compounds that are not found in animals receiving conventional feed, or at higher concentrations. ...

  13. Can volatile organic compounds be markers of sea salt?

    PubMed

    Silva, Isabel; Coimbra, Manuel A; Barros, António S; Marriott, Philip J; Rocha, Sílvia M

    2015-02-15

    Sea salt is a handmade food product that is obtained by evaporation of seawater in saltpans. During the crystallisation process, organic compounds from surroundings can be incorporated into sea salt crystals. The aim of this study is to search for potential volatile markers of sea salt. Thus, sea salts from seven north-east Atlantic Ocean locations (France, Portugal, Continental Spain, Canary Islands, and Cape Verde) were analysed by headspace solid-phase microextraction combined with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry. A total of 165 compounds were detected, ranging from 32 to 71 compounds per salt. The volatile composition revealed the variability and individuality of each salt, and a set of ten compounds were detected in all samples. From these, seven are carotenoid-derived compounds that can be associated with the typical natural surroundings of ocean hypersaline environment. These ten compounds are proposed as potential volatile markers of sea salt.

  14. Biodesulfurization techniques: Application of selected microorganisms for organic sulfur removal from coals. Final report

    SciTech Connect

    Elmore, B.B.

    1993-08-01

    As an alternative to post-combustion desulfurization of coal and pre-combustion desulfurization using physicochemical techniques, the microbial desulfurization of coal may be accomplished through the use of microbial cultures that, in an application of various microbial species, may remove both the pyritic and organic fractions of sulfur found in coal. Organisms have been isolated that readily depyritize coal but often at prohibitively low rates of desulfurization. Microbes have also been isolated that may potentially remove the organic-sulfur fraction present in coal (showing promise when acting on organic sulfur model compounds such as dibenzothiophene). The isolation and study of microorganisms demonstrating a potential for removing organic sulfur from coal has been undertaken in this project. Additionally, the organisms and mechanisms by which coal is microbially depyritized has been investigated. Three cultures were isolated that grew on dibenzothiophene (DBT), a model organic-sulfur compound, as the sole sulfur source. These cultures (UMX3, UMX9, and IGTS8) also grew on coal samples as the sole sulfur source. Numerous techniques for pretreating and ``cotreating`` coal for depyritization were also evaluated for the ability to improve the rate or extent of microbial depyritization. These include prewashing the coal with various solvents and adding surfactants to the culture broth. Using a bituminous coal containing 0.61% (w/w) pyrite washed with organic solvents at low slurry concentrations (2% w/v), the extent of depyritization was increased approximately 25% in two weeks as compared to controls. At slurry concentrations of 20% w/v, a tetrachloroethylene treatment of the coal followed by depyritization with Thiobacillus ferrooxidans increased both the rate and extent of depyritization by approximately 10%.

  15. Organic/inorganic hybrid filters based on dendritic and cyclodextrin "nanosponges" for the removal of organic pollutants from water.

    PubMed

    Arkas, Michael; Allabashi, Roza; Tsiourvas, Dimitris; Mattausch, Eva-Maria; Perfler, Reinhard

    2006-04-15

    Long-alkyl chain functionalized poly(propylene imine) dendrimer, poly(ethylene imine) hyperbranched polymer, and beta-cyclodextrin derivatives, which are completely insoluble in water, have the property of encapsulating organic pollutants from water. Ceramic porous filters can be impregnated with these compounds resulting in hybrid organic/ inorganic filter modules. These hybrid filter modules were tested for the effective purification of water, by continuous filtration experiments, employing a variety of water pollutants. It has been established that polycyclic aromatic hydrocarbons (PAHs) can be removed very efficiently (more than 95%), and final concentrations of several ppb (microg/ L) are easily obtained. Representatives of the pollutant group of trihalogen methanes (THMs), monoaromatic hydrocarbons (BTX), and pesticides (simazine) can also be removed (>80%), although the filters are saturated considerably faster in these cases.

  16. A Broad Spectrum Catalytic System for Removal of Toxic Organics from Water by Deep Oxidation - Final Report

    SciTech Connect

    Sen, Ayusman

    2000-12-01

    A most pressing need for the DOE environmental management program is the removal of toxic organic compounds present in groundwater and soil at specific DOE sites. While several remediation procedures have been proposed, they suffer from one or more drawbacks. The objective of the present research was to develop new catalytic procedures for the removal of toxic organic compounds from the environment through their deep oxidation to harmless products. In water, metallic palladium was found to catalyze the deep oxidation of a wide variety of toxic organic compounds by dioxygen at 80-90 C in the presence of carbon monoxide or dihydrogen. Several classes of organic compounds were examined: benzene, phenol and substituted phenols, nitro and halo organics, organophosphorus, and organosulfur compounds. In every case, deep oxidation to carbon monoxide, carbon dioxide, and water occurred in high yields, resulting in up to several hundred turnovers over a 24 hour period. For substrates susceptible to hydrogenation, the conversions were generally high with dihydrogen than with carbon monoxide. It is clear from the results obtained that we have discovered an exceptionally versatile catalytic system for the deep oxidation of toxic organic compounds in water. This system possesses several attractive features not found simultaneously in other reported systems. These are (a) the ability to directly utilize dioxygen as the oxidant, (b) the ability to carry out the deep oxidation of a particularly wide range of functional organics, and (c) the ease of recovery of the catalyst by simple filtration.

  17. The Photocatalytic Destruction of Volatile Organic Compounds in Water

    DTIC Science & Technology

    1991-12-10

    presently done using packed bed aeration or granular activated carbon (GAC) to remove the VOCs from the groundwater. There are problems associated with using...into another phase. UV light accelerates the rate of removal of a VOC by activating the H202, which splits into two hydroxyl radicals. These hydroxyl...540/2-90,1990). The ability of UV light to destroy organics alone is sometimes negligible. Photocatalysis is an advanced oxidation process that uses the

  18. Selective removal of phosphate for analysis of organic acids in complex samples.

    PubMed

    Deshmukh, Sandeep; Frolov, Andrej; Marcillo, Andrea; Birkemeyer, Claudia

    2015-04-03

    Accurate quantitation of compounds in samples of biological origin is often hampered by matrix interferences one of which occurs in GC-MS analysis from the presence of highly abundant phosphate. Consequently, high concentrations of phosphate need to be removed before sample analysis. Within this context, we screened 17 anion exchange solid-phase extraction (SPE) materials for selective phosphate removal using different protocols to meet the challenge of simultaneous recovery of six common organic acids in aqueous samples prior to derivatization for GC-MS analysis. Up to 75% recovery was achieved for the most organic acids, only the low pKa tartaric and citric acids were badly recovered. Compared to the traditional approach of phosphate removal by precipitation, SPE had a broader compatibility with common detection methods and performed more selectively among the organic acids under investigation. Based on the results of this study, it is recommended that phosphate removal strategies during the analysis of biologically relevant small molecular weight organic acids consider the respective pKa of the anticipated analytes and the detection method of choice. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Surfactant effects on desorption rate of nonionic organic compounds from soils to water

    USGS Publications Warehouse

    Cesare, David Di; Smith, James A.

    1994-01-01

    The widespread occurrence of organic contamination in groundwater systems has become an important environmental concern. Of particular interest are nonionic organic compounds, which sorb strongly to natural soil as a result of their characteristic low aqueous solubilities and hydrophobic nature. Consequently, the remediation of nonionic organic contamination in groundwater systems is often highly dependent on contaminant desorption from the sorbed to aqueous phase. The kinetics of desorption will significantly influence the extraction efficiency of pump-and-treat remedial methods that are capable of removing only dissolved phase contaminants.

  20. Review of hydrophilic PP membrane for organic waste removal

    NASA Astrophysics Data System (ADS)

    Ariono, Danu; Wardani, Anita Kusuma

    2017-05-01

    The acceleration of industrialization in developing countries has given an impact of environmental pollution rapidly, such as contamination of groundwater with organic waste. To solve this problem, some membrane techniques have been performed to remove organic waste from water, such as membrane contactors, membrane bioreactors, and supported liquid membranes. Polypropylene (PP) membrane is one of the promising candidates for these membrane processes due to its chemical stability, low cost, good mechanical resistance, and being easily available. However, different processes require membranes with different surface properties. Hydrophobic PP membranes with excellent chemical stability can be directly used in membrane contactors, in which the organic phase wets the porous membrane and slightly excessive pressure applied to the other phase. On the other hand, hydrophilization of PP membrane is necessary for some other processes, such as for fouling reduction on membrane bioreactors due to organic matters deposition. The aim of this paper is to give a brief overview of removal of organic waste by PP membrane. Moreover, the effects of PP surface hydrophilization on antifouling properties are also discussed.

  1. Use of Bromine and Bromo-Organic Compounds in Organic Synthesis.

    PubMed

    Saikia, Indranirekha; Borah, Arun Jyoti; Phukan, Prodeep

    2016-06-22

    Bromination is one of the most important transformations in organic synthesis and can be carried out using bromine and many other bromo compounds. Use of molecular bromine in organic synthesis is well-known. However, due to the hazardous nature of bromine, enormous growth has been witnessed in the past several decades for the development of solid bromine carriers. This review outlines the use of bromine and different bromo-organic compounds in organic synthesis. The applications of bromine, a total of 107 bromo-organic compounds, 11 other brominating agents, and a few natural bromine sources were incorporated. The scope of these reagents for various organic transformations such as bromination, cohalogenation, oxidation, cyclization, ring-opening reactions, substitution, rearrangement, hydrolysis, catalysis, etc. has been described briefly to highlight important aspects of the bromo-organic compounds in organic synthesis.

  2. Process for removing halogenated aliphatic and aromatic compounds from petroleum products

    DOEpatents

    Googin, J.M.; Napier, J.M.; Travaglini, M.A.

    1983-09-20

    A process is described for removing halogenated aliphatic and aromatic compounds, e.g., polychlorinated biphenyls, from petroleum products by solvent extraction. The halogenated aliphatic and aromatic compounds are extracted from a petroleum product into a polar solvent by contacting the petroleum product with the polar solvent. The polar solvent is characterized by a high solubility for the extracted halogenated aliphatic and aromatic compounds, a low solubility for the petroleum product and considerable solvent power for polyhydroxy compound. The preferred polar solvent is dimethylformamide. A miscible compound, such as, water or a polyhydroxy compound, is added to the polar extraction solvent to increase the polarity of the polar extraction solvent. The halogenated aliphatic and aromatic compounds are extracted from the highly-polarized mixture of water or polyhydroxy compound and polar extraction solvent into a low polar or nonpolar solvent by contacting the water or polyhydroxy compound-polar solvent mixture with the low polar or nonpolar solvent. The halogenated aliphatic and aromatic compounds and the low polar or nonpolar solvent are separated by physical means, e.g., vacuum evaporation. The polar and nonpolar solvents are recovered from recycling. The process can easily be designed for continuous operation. Advantages of the process include that the polar solvent and a major portion of the nonpolar solvent can be recycled, the petroleum products are reclaimable and the cost for disposing of waste containing polychlorinated biphenyls is significantly reduced. 1 fig.

  3. Process for removing halogenated aliphatic and aromatic compounds from petroleum products

    DOEpatents

    Googin, John M.; Napier, John M.; Travaglini, Michael A.

    1983-01-01

    A process for removing halogenated aliphatic and aromatic compounds, e.g., polychlorinated biphenyls, from petroleum products by solvent extraction. The halogenated aliphatic and aromatic compounds are extracted from a petroleum product into a polar solvent by contacting the petroleum product with the polar solvent. The polar solvent is characterized by a high solubility for the extracted halogenated aliphatic and aromatic compounds, a low solubility for the petroleum product and considerable solvent power for polyhydroxy compound. The preferred polar solvent is dimethylformamide. A miscible compound, such as, water or a polyhydroxy compound, is added to the polar extraction solvent to increase the polarity of the polar extraction solvent. The halogenated aliphatic and aromatic compounds are extracted from the highly-polarized mixture of water or polyhydroxy compound and polar extraction solvent into a low polar or nonpolar solvent by contacting the water or polyhydroxy compound-polar solvent mixture with the low polar or nonpolar solvent. The halogenated aliphatic and aromatic compounds and the low polar or nonpolar solvent are separated by physical means, e.g., vacuum evaporation. The polar and nonpolar solvents are recovered from recycling. The process can easily be designed for continuous operation. Advantages of the process include that the polar solvent and a major portion of the nonpolar solvent can be recycled, the petroleum products are reclaimable and the cost for disposing of waste containing polychlorinated biphenyls is significantly reduced.

  4. Topological research on diamagnetic susceptibilities of organic compounds.

    PubMed

    Mu, Lailong; Feng, Changjun; He, Hongmei

    2008-02-01

    A novel molecular connectivity index, (m)chi('), based on the adjacency matrix of molecular graphs and novel atomic valence connectivities, delta(i)(') for predicting the molar diamagnetic susceptibilities of organic compounds is proposed. The delta(i)(') is defined as: delta(i)(') = delta(i)(nu) x Ei=12:625, where delta(i)(nu) and E(i) are the atomic valence connectivity and the valence orbital energy of atom i, respectively. A good QSPR model for molar diamagnetic susceptibilities can be constructed from (0)chi('), (1)chi('), (2)chi(') and (4)chi(p)(') using multivariate linear regression (MLR). The correlation coefficient r, standard error, and average absolute deviation of the MLR model are 0.9918, 5.56 cgs, and 4.26 cgs, respectively, for the 721 organic compounds tested (training set). Cross-validation using the leave-one-out method demonstrates that the MLR model is highly reliable statistically. Using the MLR model, the average absolute deviations of the predicted values of molar diamagnetic susceptibility of another 360 organic compounds (test set) is 4.34 cgs. The results show that the current method is more effective than literature methods for estimating the molar diamagnetic susceptibility of an organic compound. The MLR method thus provides an acceptable model for the prediction of molar diamagnetic susceptibilities of organic compounds.

  5. Improving rubber concrete by waste organic sulfur compounds.

    PubMed

    Chou, Liang-Hisng; Lin, Chun-Nan; Lu, Chun-Ku; Lee, Cheng-Haw; Lee, Maw-Tien

    2010-01-01

    In this study, the use of crumb tyres as additives to concrete was investigated. For some time, researchers have been studying the physical properties of concrete to determine why the inclusion of rubber particles causes the concrete to degrade. Several methods have been developed to improve the bonding between rubber particles and cement hydration products (C-S-H) with the hope of creating a product with an improvement in mechanical strength. In this study, the crumb tyres were treated with waste organic sulfur compounds from a petroleum refining factory in order to modify their surface properties. Organic sulfur compounds with amphiphilic properties can enhance the hydrophilic properties of the rubber and increase the intermolecular interaction forces between rubber and C-S-H. In the present study, a colloid probe of C-S-H was prepared to measure these intermolecular interaction forces by utilizing an atomic force microscope. Experimental results showed that rubber particles treated with waste organic sulfur compounds became more hydrophilic. In addition, the intermolecular interaction forces increased with the adsorption of waste organic sulfur compounds on the surface of the rubber particles. The compressive, tensile and flexural strengths of concrete samples that included rubber particles treated with organic sulfur compound also increased significantly.

  6. Composition and major sources of organic compounds in urban aerosols

    NASA Astrophysics Data System (ADS)

    Bi, Xinhui; Simoneit, Bernd R. T.; Sheng, Guoying; Ma, Shexia; Fu, Jiamo

    Total suspended particles (TSP), collected during June 2002 to July 2003 in Guangzhou, a typical economically developed city in South China, were analyzed for the organic compound compositions using gas chromatography-mass spectrometry (GC/MS). Over 140 organic compounds were detected in the aerosols and grouped into different classes including n-alkanes, hopanoids, polycyclic aromatic hydrocarbons, alkanols, fatty acids, dicarboxylic acids excluding oxalic acid, polyols/polyacids, lignin products, phytosterols, phthalates and water-soluble sugars. The total amounts of the identified organic compounds including unresolved complex mixture (UCM) ranged from 3112 ng/m 3 in spring to 5116 ng/m 3 in winter, comprising on seasonal average 2.8% of TSP. Primary organic compounds peaked in winter although there are no heating systems burning fuels in Guangzhou. The highest saccharide levels occurred in fall due to agricultural activities. This study demonstrated that utilization of fossil fuels, biomass burning, soil resuspension and plastic/refuse burning are the major contributors to the identified organic compounds in the urban atmosphere of South China.

  7. Well-purging criteria for sampling purgeable organic compounds

    USGS Publications Warehouse

    Gibs, J.; Imbrigiotta, T.E.

    1990-01-01

    The results indicate that 1) purgeable organic compound concentrations stabilized when three casing volume were purged in only 55% of the cases evaluated in this study, 2) purgeable organic compounds concentrations did not consistently follow the temporal variation of, nor stabilize at the same time as, the measure field characteristics, and 3) purging to achieve hydraulic equilibrium between casing and aquifer water consistently underestimated the time and casing volumes needed to achieve stable values of water-quality measurements in highly transmissive aquifers. The conclusion from these data is that none of the previously recommended criteria for purging a well can be applied reliably to collecting a "representative' sample of purgeable organic compounds. These results indicate that the criteria for purging a well prior to sampling for purgeable organic compounds must take into account other factors, such as the unique hydrogeologic characteristics of a site, the nature and extent of purgeable organic compounds present, and areal extent of the contamination, the well construction, and the sampling objectives of the investigation. -from Authors

  8. Removal of selected emerging PPCP compounds using greater duckweed (Spirodela polyrhiza) based lab-scale free water constructed wetland.

    PubMed

    Li, Jianan; Zhou, Qizhi; Campos, Luiza C

    2017-09-14

    Greater duckweed (Spirodela polyrhiza) based lab-scale free water constructed wetland (CW) was employed for removing four emerging pharmaceuticals and personal care products (PPCPs) (i.e. DEET, paracetamol, caffeine and triclosan). Orthogonal design was used to test the effect of light intensity, aeration, E.coli abundance and plant biomass on the target compounds. Synthetic wastewater contaminated with the target compounds at concentration of 25 μg/L was prepared, and both batch and continuous flow experiments were conducted. Up to 100% removals were achieved for paracetamol (PAR), caffeine (CAF) and tricolsan (TCS) while the highest removal for DEET was 32.2% in batch tests. Based on orthogonal Duncan analysis, high light intensity (240 μmolmm(-2)s(-1)), full aeration, high plant biomass (1.00 kg/m(2)) and high E.coli abundance (1.0 × 10(6) CFU/100 mL) favoured elimination of the PPCPs. Batch verification test achieved removals of 17.1%, 98.8%, 96.4% and 95.4% for DEET, PAR, CAF and TCS respectively. Continuous flow tests with CW only and CW followed by stabilization tank (CW-ST) were carried out. Final removals of the PPCP contaminants were 32.6%, 97.7%, 98.0% and 100% for DEET, PAR, CAF and TCS, respectively, by CW system alone, while 43.3%, 97.5%, 98.2% and 100%, respectively, were achieved by CW-ST system. By adding the ST tank, PPCP concentrations decreased significantly faster (p < 0.05) compared with continuous flow CW alone. In addition, after removing aerators during continuous flow CW experiments, the treatment systems presented good stability for the PPCP removals. CW-ST showed better chemical oxygen demand (COD) and total organic carbon (TOC) removals (89.3%, 91.2%, respectively) than CW only (79.4%, 85.2%, respectively). However, poor DEET removal (<50%) and high E.coli abundance (up to 1.7 log increase) in the final treated water indicated further treatment processes may be required. Statistical analysis showed significant correlations

  9. The Use of Modified Bentonite for Removal of Aromatic Organics from Contaminated Soil.

    PubMed

    Gitipour; Bowers; Bodocsi

    1997-12-15

    This study investigates the clay-aromatic interactions with a view to the use of bentonite clay for binding benzene, toluene, ethylbenzene, and o-xylene (BTEX compounds) in contaminated soils. BTEX compounds are the most toxic aromatic constituents of gasoline present in many underground storage tanks. Modified (organophilic) and ordinary bentonites are used to remove these organics. The organophilic bentonites are prepared by replacing the exchangeable inorganic cations present in bentonite particles with a quaternary ammonium salt. Various clay-to-soil ratios were applied to determine the efficiency of the modified bentonite in enhancing the cement-based solidification/stabilization (S/S) of BTEX contaminated soils. Toxicity characteristics leaching procedure (TCLP) tests were performed on soil samples to evaluate the leaching of the organics. In addition, X-ray diffraction analyses were conducted to assess the changes in the basal spacing of the clays as a result of their interaction with BTEX compounds. The findings of this study reveal that organophilic bentonite can act as a successful adsorbent for removing the aromatic organics from contaminated soil. Thus, this material is viable for enhancing the performance of cement-based S/S processes, as an adsorbent for petroleum spills, and for landfill liners and slurry walls. Copyright 1997 Academic Press.

  10. Volatile organic compounds in Gulf of Mexico sediments

    SciTech Connect

    McDonald, T.J.

    1988-01-01

    Volatile organic compounds (VOC), concentrations and compositions were documented for estuarine, coastal, shelf, slope, and deep water sediments from the Gulf of Mexico. VOC were measured (detection limit >0.01 ppb) using a closed-loop stripping apparatus with gas chromatography (GC) and flame ionization, flame photometric, and mass spectrometric detectors. The five primary sources of Gulf of Mexico sediment VOC are: (1) planktonic and benthic fauna and flora; (2) terrestrial material from riverine and atmospheric deposition; (3) anthropogenic inputs: (4) upward migration of hydrocarbons; and (5) transport by bottom currents or slumping. Detected organo-sulfur compounds include alkylated sulfides, thiophene, alkylated thiophenes, and benzothiophenes. Benzothiophenes are petroleum related. Low molecular weight organo-sulfur compounds result from the biological oxidation of organic matter. A lack of organosulfur compounds in the reducing environment of the Orca Basin may result from a lack of free sulfides which are necessary for their production.

  11. Organic compounds in the particulate matter from burning organic soils

    Treesearch

    Charles K. McMahon; Jerry D. White; Skevos N. Tsoukalas

    1985-01-01

    This paper is directed to people interested in the environmental impact of natural emissions. Natural emissions are common and contribute significantly to tropospheric background levels. Several million hectares of the United States are covered by organic soils. During droughts, these soils can ignite and support slow combustion which often persists for weeks causing...

  12. Air ionization as a control technology for off-gas emissions of volatile organic compounds.

    PubMed

    Kim, Ki-Hyun; Szulejko, Jan E; Kumar, Pawan; Kwon, Eilhann E; Adelodun, Adedeji A; Reddy, Police Anil Kumar

    2017-06-01

    High energy electron-impact ionizers have found applications mainly in industry to reduce off-gas emissions from waste gas streams at low cost and high efficiency because of their ability to oxidize many airborne organic pollutants (e.g., volatile organic compounds (VOCs)) to CO2 and H2O. Applications of air ionizers in indoor air quality management are limited due to poor removal efficiency and production of noxious side products, e.g., ozone (O3). In this paper, we provide a critical evaluation of the pollutant removal performance of air ionizing system through comprehensive review of the literature. In particular, we focus on removal of VOCs and odorants. We also discuss the generation of unwanted air ionization byproducts such as O3, NOx, and VOC oxidation intermediates that limit the use of air-ionizers in indoor air quality management. Copyright © 2017. Published by Elsevier Ltd.

  13. Volatile and semivolatile organic compounds in laboratory peat fire emissions

    NASA Astrophysics Data System (ADS)

    George, Ingrid J.; Black, Robert R.; Geron, Chris D.; Aurell, Johanna; Hays, Michael D.; Preston, William T.; Gullett, Brian K.

    2016-05-01

    In this study, volatile and semi-volatile organic compound (VOCs and SVOCs) mass emission factors were determined from laboratory peat fire experiments. The peat samples originated from two National Wildlife Refuges on the coastal plain of North Carolina, U.S.A. Gas- and particle-phase organic compounds were quantified by gas chromatography-mass spectrometry and by high pressure liquid chromatography. Hazardous air pollutants (HAPs) accounted for a large fraction (∼60%) of the speciated VOC emissions from peat burning, including large contributions of acetaldehyde, formaldehyde, benzene, toluene, and chloromethane. In the fine particle mass (PM2.5), the following organic compound classes were dominant: organic acids, levoglucosan, n-alkanes, and n-alkenes. Emission factors for the organic acids in PM2.5 including n-alkanoic acids, n-alkenoic acids, n-alkanedioic acids, and aromatic acids were reported for the first time for peat burning, representing the largest fraction of organic carbon (OC) mass (11-12%) of all speciated compound classes measured in this work. Levoglucosan contributed to 2-3% of the OC mass, while methoxyphenols represented 0.2-0.3% of the OC mass on a carbon mass basis. Retene was the most abundant particulate phase polycyclic aromatic hydrocarbon (PAH). Total HAP VOC and particulate PAH emissions from a 2008 peat wildfire in North Carolina were estimated, suggesting that peat fires can contribute a large fraction of state-wide HAP emissions.

  14. Use of microwaves for in-situ removal of pollutant compounds from solid matrices.

    PubMed

    Barba, A A; Acierno, D; d'Amore, M

    2012-03-15

    Thermal treatments are the most used methods to remediate contaminated solids. However, they may seriously damage the otherwise recoverable matrices, especially when mild operating conditions cannot be used. Microwaves recently raised as a powerful tool in industrial engineering for their ability, among other advantages, to offer a selected heating, thus allowing to treat and remove only the undesired components of a matrix. This work approaches the microwave assisted thermal treatments of waste from a physical-chemical point of view. Two recovering operations have been performed, respectively, on a soil contaminated by volatile organic compounds and on a ceramic filter spoiled by soot, using two specially designed prototypes, both realized on pre-pilot scale. The heat and mass transfer balances have then been analyzed in their more general form, and terms related to the use of microwaves outlined. Solutions of the differential equations have been applied to interpret the effects of microwaves on rate and efficiency of the remediation processes. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. GROUNDWATER TRANSPORT OF HYDROPHOBIC ORGANIC COMPOUNDS IN THE PRESENCE OF DISSOLVED ORGANIC MATTER

    EPA Science Inventory

    The effects of dissolved organic matter (DOM) on the transport of hydrophobic organic compounds in soil columns were investigated. Three compounds (naphthalene, phenanthrene and DDT) that spanned three orders of magnitude in water solubility were used. Instead of humic matter, mo...

  16. GROUNDWATER TRANSPORT OF HYDROPHOBIC ORGANIC COMPOUNDS IN THE PRESENCE OF DISSOLVED ORGANIC MATTER

    EPA Science Inventory

    The effects of dissolved organic matter (DOM) on the transport of hydrophobic organic compounds in soil columns were investigated. Three compounds (naphthalene, phenanthrene and DDT) that spanned three orders of magnitude in water solubility were used. Instead of humic matter, mo...

  17. Composition, removal, redox, and metal complexation properties of dissolved organic nitrogen in composting leachates.

    PubMed

    He, Xiao-Song; Xi, Bei-Dou; Zhang, Zong-Yong; Gao, Ru-Tai; Tan, Wen-Bing; Cui, Dong-Yu; Yuan, Ying

    2015-01-01

    This study investigated the composition, removal, redox, and metal complexation characteristics of dissolved organic nitrogen (DON) in composting leachates. Results showed that the leachate-derived DON comprised proteinaceous compounds and amines, and most of them were integrated into the fulvic- and humic-like substances. Neutral, basic, acidic, hydroxylic, aromatic, and sulfuric amino acids all were detected in the influent leachates. However, most of them were removed by the biological and physical processes, and only neutral amino acids were detected in the effluent. The DON was not the main contributor to the redox capability of the leachate dissolved organic matter (DOM). However, it exhibited a strong capability for metal complexation. The amines formed strong complexes with the metals Mo, Co, Cr, and Ni, while the proteinaceous matter interacted with the metals Cr and Ni. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Dosimeter for monitoring vapors and aerosols of organic compounds

    DOEpatents

    Vo-Dinh, T.

    1987-07-14

    A dosimeter is provided for collecting and detecting vapors and aerosols of organic compounds. The dosimeter comprises a lightweight, passive device that can be conveniently worn by a person as a badge or placed at a stationary location. The dosimeter includes a sample collector comprising a porous web treated with a chemical for inducing molecular displacement and enhancing phosphorescence. Compounds are collected onto the web by molecular diffusion. The web also serves as the sample medium for detecting the compounds by a room temperature phosphorescence technique. 7 figs.

  19. Dosimeter for monitoring vapors and aerosols of organic compounds

    DOEpatents

    Vo-Dinh, Tuan

    1987-01-01

    A dosimeter is provided for collecting and detecting vapors and aerosols of organic compounds. The dosimeter comprises a lightweight, passive device that can be conveniently worn by a person as a badge or placed at a stationary location. The dosimeter includes a sample collector comprising a porous web treated with a chemical for inducing molecular displacement and enhancing phosphorescence. Compounds are collected onto the web by molecular diffusion. The web also serves as the sample medium for detecting the compounds by a room temperature phosphorescence technique.

  20. REMOVAL OF ORGANIC CHEMICALS FROM WASTEWATER BY SURFACTANT SEPARATION

    SciTech Connect

    Unknown

    2002-01-01

    This research presents a novel hybrid process for removing organic chemicals from contaminated water. The process uses surfactant to carry out two unit operations (1) Extraction; (2) Foam flotation. In the first step, surfactant is used to extract most of the amounts of organic contaminants in the stream. In the second step, foam flotation is used to further reduce organic contaminants and recover surfactant from the stream. The process combines the advantages of extraction and foam flotation, which allows the process not only to handle a wide range of organic contaminants, but also to effectively treat a wide range of the concentration of organic contaminants in the stream and reduce it to a very low level. Surfactant regeneration can be done by conventional methods. This process is simple and low cost. The wastes are recoverable. The objective of this research is to develop an environmentally innocuous process for the wastewater or reclaimed water treatment with the ability to handle a wide range of organic contaminants, also to effectively treat a wide range of the concentration of organic contaminants in contaminated water and reduce it to a very low level, finally, provides simpler, less energy cost and economically-practical process design. Another purpose is to promote the environmental concern in minority students and encourage minority students to become more involved in environmental engineering research.

  1. Laboratory and field evaluation of a pretreatment system for removing organics from produced water.

    PubMed

    Kwon, Soondong; Sullivan, Enid J; Katz, Lynn E; Bowman, Robert S; Kinney, Kerry A

    2011-09-01

    Co-produced water from the oil and gas industry accounts for a significant waste stream in the United States. This "produced water" is characterized by saline water containing a variety of pollutants, including water soluble and immiscible organics and many inorganic species. To reuse produced water, removal of both the inorganic dissolved solids and organic compounds is necessary. In this research, the effectiveness of a pretreatment system consisting of surfactant modified zeolite (SMZ) adsorption followed by a membrane bioreactor (MBR) was evaluated for simultaneous removal of carboxylates and hazardous substances, such as benzene, toluene, ethylbenzene, and xylenes (BTEX) from saline-produced water. A laboratory-scale MBR, operated at a 9.6-hour hydraulic residence time, degraded 92% of the carboxylates present in synthetic produced water. When BTEX was introduced simultaneously to the MBR system with the carboxylates, the system achieved 80 to 95% removal of BTEX via biodegradation. These results suggest that simultaneous biodegradation of both BTEX and carboxylate constituents found in produced water is possible. A field test conducted at a produced water disposal facility in Farmington, New Mexico confirmed the laboratory-scale results for the MBR and demonstrated enhanced removal of BTEX using a treatment train consisting of SMZ columns followed by the MBR. While most of the BTEX constituents of the produced water adsorbed onto the SMZ adsorption system, approximately 95% of the BTEX that penetrated the SMZ and entered the MBR was biodegraded in the MBR. Removal rates of acetate (influent concentrations of 120 to 170 mg/L) ranged from 91 to 100%, and total organic carbon (influent concentrations as high as 580 mg/L) ranged from 74 to 92%, respectively. Organic removal in the MBR was accomplished at a low biomass concentration of 1 g/L throughout the field trial. While the transmembrane pressure during the laboratory-scale tests was well-controlled, it rose

  2. Enhancing the bioavailability of organic compounds sequestered in soil and aquifer solids

    SciTech Connect

    White, J.C.; Alexander, M.; Pignatello, J.J.

    1999-02-01

    A study was conducted to find ways to increase the biodegradability of compounds that have aged in soil or aquifer material and become less bioavailable. Slurrying enhanced the rate and extent of biodegradation by individual bacterial strains of aged and unaged phenanthrene and di(2-ethylhexyl) phthalate in soils and aquifer solids. After bacterial degradation of aged phenanthrene in unslurried soil had largely ceased, the residual compound was metabolized if the soil was slurried and reinoculated with a phenanthrene-degrading bacterium. The rate and extent of biodegradation of aged phenanthrene by Pseudomonas sp. were enhanced when anthracene or pyrene was added to the soil at the same time as the bacterium, although the organism could not metabolize anthracene or pyrene. Moreover, anthracene or pyrene increased the amount of aged phenanthrene removed from soil by a mild extractant. The data show that the bioavailability of organic compounds that become sequestered by aging can be altered by appropriate soil treatments.

  3. Simplified Production of Organic Compounds Containing High Enantiomer Excesses

    NASA Technical Reports Server (NTRS)

    Cooper, George W. (Inventor)

    2015-01-01

    The present invention is directed to a method for making an enantiomeric organic compound having a high amount of enantiomer excesses including the steps of a) providing an aqueous solution including an initial reactant and a catalyst; and b) subjecting said aqueous solution simultaneously to a magnetic field and photolysis radiation such that said photolysis radiation produces light rays that run substantially parallel or anti-parallel to the magnetic field passing through said aqueous solution, wherein said catalyst reacts with said initial reactant to form the enantiomeric organic compound having a high amount of enantiomer excesses.

  4. Removal of Biologically Active Organic Contaminants using Atomic Oxygen

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A. (Inventor); Banks, Michael A. (Inventor); Banks, Eric B. (Inventor)

    2003-01-01

    Biomedical devices that are to come into contact with living tissue, such as prosthetic and other implants for the human body and the containers used to store and transport them, are together cleaned of non-living, but biologically active organic materials, including endotoxins such as lipopolysaccharides, and assembled into a hermetically sealed package without recontamination. This is achieved by cleaning both the device and package components together in an apparatus, which includes a hermetically sealed chamber, in which they are contacted with atomic oxygen which biocleans them, by oxidizing the biologically active organic materials. The apparatus also includes means for manipulating the device and container and hermetically sealing the cleaned device into the cleaned container to form the package. A calibrated witness coupon visually indicates whether or not the device and container have received enough exposure to the atomic oxygen to have removed the organic materials from their surfaces. Gamma radiation is then used to sterilize the device in the sealed container.

  5. Organic pollutants removal in wastewater by heterogeneous photocatalytic ozonation.

    PubMed

    Xiao, Jiadong; Xie, Yongbing; Cao, Hongbin

    2015-02-01

    Heterogeneous photocatalysis and ozonation are robust advanced oxidation processes for eliminating organic contaminants in wastewater. The combination of these two methods is carried out in order to enhance the overall mineralization of refractory organics. An apparent synergism between heterogeneous photocatalysis and ozonation has been demonstrated in many literatures, which gives rise to an improvement of total organic carbon removal. The present overview dissects the heterogeneous catalysts and the influences of different operational parameters, followed by the discussion on the kinetics, mechanism, economic feasibility and future trends of this integrated technology. The enhanced oxidation rate mainly results from a large amount of hydroxyl radicals generated from a synergistically induced decomposition of dissolved ozone, besides superoxide ion radicals and the photo-induced holes. Six reaction pathways possibly exist for the generation of hydroxyl radicals in the reaction mechanism of heterogeneous photocatalytic ozonation.

  6. Removal of Biologically Active Organic Contaminants using Atomic Oxygen

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A. (Inventor); Banks, Michael A. (Inventor); Banks, Eric B. (Inventor)

    2003-01-01

    Biomedical devices that are to come into contact with living tissue, such as prosthetic and other implants for the human body and the containers used to store and transport them, are together cleaned of non-living, but biologically active organic materials, including endotoxins such as lipopolysaccharides, and assembled into a hermetically sealed package without recontamination. This is achieved by cleaning both the device and package components together in an apparatus, which includes a hermetically sealed chamber, in which they are contacted with atomic oxygen which biocleans them, by oxidizing the biologically active organic materials. The apparatus also includes means for manipulating the device and container and hermetically sealing the cleaned device into the cleaned container to form the package. A calibrated witness coupon visually indicates whether or not the device and container have received enough exposure to the atomic oxygen to have removed the organic materials from their surfaces. Gamma radiation is then used to sterilize the device in the sealed container.

  7. Optimized removal of dissolved organic carbon and trace organic contaminants during combined ozonation and artificial groundwater recharge.

    PubMed

    Hübner, U; Miehe, U; Jekel, M

    2012-11-15

    Pilot scale experiments using an 8 g/h ozonation unit and a 1.4 m(2) slow sand filter have demonstrated that the combination of ozonation and artificial groundwater recharge is suitable for efficient reduction of bulk and trace organics. The biodegradation of dissolved organic carbon (DOC) in the slow sand filter was enhanced from 22% without pre-treatment to 34% by pre-ozonation. In addition, realistic surface water concentrations of most investigated trace organic compounds (TrOCs) including carbamazepine, sulfamethoxazole, phenazone and metoprolol were reduced below the limits of quantification. Only a few TrOCs, e.g. primidone and benzotriazole, were not efficiently removed in both treatment steps and could be detected regularly in the filter effluent. For these compounds, enhanced treatment, such as advanced oxidation processes, needs to be considered. Testing for genotoxicity and cytotoxicity did not reveal any systematic adverse effects for human health. The formation of the by-product bromate from bromide was below the limit of the German drinking water directive of 10 μg/L. No removal of bromate was observed in the aerobic slow sand filter. Additional experiments with sand columns showed that operating a preceding bank filtration step to reduce DOC can reduce oxidant demand by approximately 20%. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Measurements of bromine containing organic compounds at the tropical tropopause

    NASA Astrophysics Data System (ADS)

    Schauffler, S. M.; Atlas, E. L.; Flocke, F.; Lueb, R. A.; Stroud, V.; Travnicek, W.

    The amount of bromine entering the stratosphere from organic source gases is a primary factor involved in determining the magnitude of bromine catalyzed loss of ozone. Thirty two whole air samples were collected at the tropical tropopause during the NASA STRAT Campaign in Feb., Aug., and Dec., 1996 and were analyzed for brominated organic compounds. Total organic bromine was 17.4±0.9 ppt with 55% from methyl bromide, 38% from the Halons, 6% from dibromomethane, and 0.8% from bromochloromethane and dichlorobromomethane. One flight showed the presence of 0.42 ppt of additional organic bromine from bromoform and dibromochloromethane.

  9. Detection of Organic Compounds with Whole-Cell Bioluminescent Bioassays

    PubMed Central

    Xu, Tingting; Close, Dan; Smartt, Abby; Ripp, Steven

    2015-01-01

    Natural and manmade organic chemicals are widely deposited across a diverse range of ecosystems including air, surface water, groundwater, wastewater, soil, sediment, and marine environments. Some organic compounds, despite their industrial values, are toxic to living organisms and pose significant health risks to humans and wildlife. Detection and monitoring of these organic pollutants in environmental matrices therefore is of great interest and need for remediation and health risk assessment. Although these detections have traditionally been performed using analytical chemical approaches that offer highly sensitive and specific identification of target compounds, these methods require specialized equipment and trained operators, and fail to describe potential bioavailable effects on living organisms. Alternatively, the integration of bioluminescent systems into whole-cell bioreporters presents a new capacity for organic compound detection. These bioreporters are constructed by incorporating reporter genes into catabolic or signaling pathways that are present within living cells and emit a bioluminescent signal that can be detected upon exposure to target chemicals. Although relatively less specific compared to analytical methods, bioluminescent bioassays are more cost-effective, more rapid, can be scaled to higher throughput, and can be designed to report not only the presence but also the bioavailability of target substances. This chapter reviews available bacterial and eukaryotic whole-cell bioreporters for sensing organic pollutants and their applications in a variety of sample matrices. PMID:25084996

  10. Comparative assessment of LECA and Spartina maritima to remove emerging organic contaminants from wastewater.

    PubMed

    Ferreira, Ana Rita; Guedes, Paula; Mateus, Eduardo P; Ribeiro, Alexandra B; Couto, Nazaré

    2017-01-18

    The present work aimed to evaluate the capacity of constructed wetlands (CWs) to remove three emerging organic contaminants with different physicochemical properties: caffeine (CAF), oxybenzone (MBPh), and triclosan (TCS). The simulated CWs were set up with a matrix of light expanded clay aggregates (LECA) and planted with Spartina maritima, a salt marsh plant. Controlled experiments were carried out in microcosms using deionized water and wastewater collected at a wastewater treatment plant (WWTP), with different contaminant mass ranges, for 3, 7, and 14 days. The effects of variables were tested isolatedly and together (LECA and/or S. maritima). The presence of LECA and/or S. maritima has shown higher removal (around 61-97%) of lipophilic compounds (MBPh and TCS) than the hydrophilic compound (CAF; around 19-85%). This was attributed to the fact that hydrophilic compounds are dissolved in the water column, whereas the lipophilic ones suffer sorption processes promoting their removal by plant roots and/or LECA. In the control (only wastewater), a decrease in the three contaminant levels was observed. Adsorption and bio/rhizoremediation are the strongest hypothesis to explain the decrease in contaminants in the tested conditions.

  11. Organic compounds in hot-water-soluble fractions from water repellent soils

    NASA Astrophysics Data System (ADS)

    Atanassova, Irena; Doerr, Stefan

    2014-05-01

    Water repellency (WR) is a soil property providing hydrophobic protection and preventing rapid microbial decomposition of organic matter entering the soil with litter or plant residues. Global warming can cause changes in WR, thus influencing water storage and plant productivity. Here we assess two different approaches for analysis of organic compounds composition in hot water extracts from accelerated solvent extraction (ASE) of water repellent soils. Extracts were lyophilized, fractionated on SiO2 (sand) and SPE cartridge, and measured by GC/MS. Dominant compounds were aromatic acids, short chain dicarboxylic acids (C4-C9), sugars, short chain fatty acids (C8-C18), and esters of stearic and palmitic acids. Polar compounds (mainly sugars) were adsorbed on applying SPE clean-up procedure, while esters were highly abundant. In addition to the removal of polar compounds, hydrophobic esters and hydrocarbons (alkanes and alkenes < C20) were extracted through desorption of complex colloids stabilized as micelles in dissolved organic carbon (DOC). Water repellency was completely eliminated by hot water under high pressure. The molecular composition of HWSC can play a critical role in stabilization and destabilization of soil organic matter (SOM), particle wettability and C dynamics in soils. Key words: soil water repellency, hot water soluble carbon (HWSC), GC/MS, hydrophobic compounds

  12. Adsorptive removal and separation of chemicals with metal-organic frameworks: Contribution of π-complexation.

    PubMed

    Khan, Nazmul Abedin; Jhung, Sung Hwa

    2017-03-05

    Efficient removal and separation of chemicals from the environment has become a vital issue from a biological and environmental point of view. Currently, adsorptive removal/separation is one of the most promising approaches for cleaning purposes. Selective adsorption/removal of various sulfur- and nitrogen-containing compounds, olefins, and π-electron-rich gases via π-complex formation between an adsorbent and adsorbate molecules is very competitive. Porous metal-organic framework (MOF) materials are very promising in the adsorption/separation of various liquids and gases owing to their distinct characteristics. This review summarizes the literature on the adsorptive removal/separation of various π-electron-rich compounds mainly from fuel and gases using MOF materials containing metal ions that are active for π-complexation. Details of the π-complexation, including mechanism, pros/cons, applications, and efficient ways to form the complex, are discussed systematically. For in-depth understanding, molecular orbital calculations regarding charge transfer between the π-complexing species are also explained in a separate section. From this review, readers will gain an understanding of π-complexation for adsorption and separation, especially with MOFs, to develop new insight for future research.

  13. Surface modification of inorganic layer compound with organic compound and preparation of thin films

    NASA Astrophysics Data System (ADS)

    Tagaya, Hideyuki; Morioka, Hiroyuki; Ogata, Sumikazu; Karasu, Masa; Kadokawa, Jun-ichi; Chiba, Koji

    1997-11-01

    Water treated Zn/Al layered double hydroxide (LDH) was prepared by the reaction of LDH oxide and water. By the reaction of the water treated Zn/Al LDH or amorphous metal hydroxide and organic oxychloride, surface modified inorganic layer compounds were prepared. Their layer structures were similar to those of the orginal LDHs except the reaction product of amorphous metal hydroxide and benzoyl chloride. Interlayer spacings of the reaction products were 0.77 to 2.67 nm depending on the size and number of function groups of organic compounds.

  14. Magnetic pollen grains as sorbents for facile removal of organic pollutants in aqueous media.

    PubMed

    Thio, Beng Joo Reginald; Clark, Kristin K; Keller, Arturo A

    2011-10-30

    Plant materials have long been demonstrated to sorb organic compounds. However, there are no known reports about pollen grains acting as sorbents to remove hydrophobic organic compounds (HOCs) such as pesticides, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) from contaminated waters. We report a facile and effective method to remove HOCs from water using magnetized short ragweed (Ambrosia artemisiifolia) pollen grains. We dispersed the magnetized pollen grains in two different water samples - deionized (DI) and natural storm water to mimic real environmental conditions likely to be encountered during treatment. The magnetized pollen grains were readily separated from the aqueous media via a magnetic field after adsorption of the HOCs. We measured the adsorption of five representative HOCs (acenaphthene, phenanthrene, atrazine, diuron, and lindane) onto magnetized ragweed pollen in different aqueous matrices. We demonstrate that the adsorption capacity of the magnetized ragweed pollen can be regenerated to a large extent for reuse as a sorbent. Our results also indicate that the magnetized pollen grains are as effective as activated carbon (AC) in removing HOCs from both types of contaminated waters. The high HOC sorption of the ragweed pollen allows it to have potential remediation application in the field under realistic conditions.

  15. Amphiphobic Polytetrafluoroethylene Membranes for Efficient Organic Aerosol Removal.

    PubMed

    Feng, Shasha; Zhong, Zhaoxiang; Zhang, Feng; Wang, Yong; Xing, Weihong

    2016-04-06

    Polytetrafluoroethylene (PTFE) membrane is an extensively used air filter, but its oleophilicity leads to severe fouling of the membrane surface due to organic aerosol deposition. Herein, we report the fabrication of a new amphiphobic 1H,1H,2H,2H-perfluorodecyl acrylate (PFDAE)-grafted ZnO@PTFE membrane with enhanced antifouling functionality and high removal efficiency. We use atomic-layer deposition (ALD) to uniformly coat a layer of nanosized ZnO particles onto porous PTFE matrix to increase surface area and then subsequently graft PFDAE with plasma. Consequently, the membrane surface showed both superhydrophobicity and oleophobicity with a water contact angle (WCA) and an oil contact angle (OCA) of 150° and 125°, respectively. The membrane air permeation rate of 513 (m(3) m(-2) h(-1) kPa(-1)) was lower than the pristine membrane rate of 550 (m(3) m(-2) h(-1) kPa(-1)), which indicates the surface modification slightly decreased the membrane air permeation. Significantly, the filtration resistance of this amphiphobic membrane to the oil aerosol system was much lower than the initial one. Moreover, the filter exhibited exceptional organic aerosol removal efficiencies that were greater than 99.5%. These results make the amphiphobic PTFE membranes very promising for organic aerosol-laden air-filtration applications.

  16. A general mathematical model for chemical-enhanced flushing of soil contaminated by organic compounds

    NASA Astrophysics Data System (ADS)

    Ji, Wei; Brusseau, Mark L.

    The use of chemical agents to enhance the in situ removal of hydrophobic organic compounds (HOCs) from porous media is an emerging remediation technology. Whereas surfactants and cosolvents are the primary agents examined to date, others, such as natural organic matter and complexing agents, have also been examined for their ability to enhance the solubilization of HOCs. While the mode of action of each type of enhanced-solubilization agent may be different, they all induce similar responses. In this paper, a general mathematical model is developed to simulate the enhanced-solubilization process for various chemical agents, including cosolvents, surfactants, natural organic matter, and complexing agents. This model is developed using a master-equation approach that incorporates the solubilization mechanisms associated with each type of agent. A limited evaluation of the model is conducted by comparing simulations to the results of two laboratory experiments. A sensitivity analysis is performed to illustrate the influence of various factors on contaminant removal.

  17. Chemical reactions of organic compounds on clay surfaces.

    PubMed Central

    Soma, Y; Soma, M

    1989-01-01

    Chemical reactions of organic compounds including pesticides at the interlayer and exterior surfaces of clay minerals and with soil organic matter are reviewed. Representative reactions under moderate conditions possibly occurring in natural soils are described. Attempts have been made to clarify the importance of the chemical nature of molecules, their structures and their functional groups, and the Brönsted or Lewis acidity of clay minerals. PMID:2533556

  18. The photostabililty of prebiotic organic compounds on cometary dusts.

    NASA Astrophysics Data System (ADS)

    Saiagh, K.; Aleian, A.; Fray, N.; Cloix, M.; Cottin, H.

    2013-09-01

    A new methodology for measuring the photostability of organic compounds in extraterrestrial environments will be presented. It is based on Low Earth Orbit (LEO) and "classical" laboratory photolysis experiments, as well as on quantitative measurements of the VUV/UV ( < 300 nm) absorption cross section spectra. We will discuss the complementarily and limits of each approach, and discuss the astrobiological relevance of such studies in the frame of the importation of organic matter to Earth via micrometeorites.

  19. Organic xenobiotics removal in constructed wetlands, with emphasis on the importance of the support matrix.

    PubMed

    Dordio, A V; Carvalho, A J P

    2013-05-15

    Constructed wetlands (CWs) are increasingly popular as an efficient and economical alternative to conventional wastewater treatment processes for removal, among other pollutants, of organic xenobiotics. In CWs, pollutants are removed through the concerted action of their components, whose contribution can be maximized by careful selection of those components. Specifically for non-biodegradable organic pollutants, the materials used as support matrix of CWs can play a major role through sorption phenomena. In this review the role played by such materials in CWs is examined with special focus on the amount of research that has been conducted to date on their sorption properties relatively to organic compounds. Where available, the reports on the utilization of some of those materials on pilot or full-scale CWs are also recognized. Greatest interest has been directed to cheaper and widely available materials. Among these, clays are generally regarded as efficient sorbents, but materials originated from agricultural wastes have also gained recent popularity. Most available studies are lab-scale batch sorption experiments, whereas assays performed in full-scale CWs are still scarce. However, the available lab-scale data points to an interesting potential of many of these materials for experimentation as support matrix of CWs targeted for organic xenobiotics removal.

  20. Regulatory Off-Gas Analysis from the Evaporation of Hanford Simulated Waste Spiked with Organic Compounds

    SciTech Connect

    Calloway, T.B. Jr.

    2003-10-23

    After strontium/transuranics removal by precipitation followed by cesium/technetium removal by ion exchange, remaining low activity waste in the Hanford River Protection Project Waste Treatment Plant is to be concentrated by evaporation prior to being mixed with glass formers and vitrified. To provide a technical basis to permit the waste treatment facility, a relatively organic-rich Hanford Tank 241-AN-107 waste simulant was spiked with 14 target volatile, semi-volatile and pesticide compounds, and evaporated under vacuum in a bench-scale natural circulation evaporator fitted with an industrial stack off-gas sampler at the Savannah River Technology Center. An evaporator material balance for the target organics was calculated by combining liquid stream mass and analytical data with off-gas emissions estimates obtained using EPA SW-846 Methods. Volatile and light semi-volatile organic compounds in the waste simulant were found to largely exit through the condenser vent, while heavier semi-volatiles and pesticides generally remain in the evaporator concentrate. An OLI Environmental Simulation Program evaporator model successfully predicted operating conditions and the experimental distribution of the fed target organics exiting in the concentrate, condensate and off-gas streams with the exception of a few semi-volatile and pesticide compounds. Comparison with Henry's Law predictions suggests the OLI ESP model is constrained by available literature data.