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Final Report: Transformation Reactions of Nitroaromatic and Nitrogen Heterocyclic Compounds on Granular Activated Carbon (GAC) Surfaces: Enhancement of GAC Adsorption in Natural and Engineered Environmental Systems
EPA Grant Number: R826694C636Subproject: this is subproject number 636 , established and managed by the Center Director under grant R828598
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
Center: Gulf Coast HSRC (Lamar)
Center Director: Ho, Tho C.
Title: Transformation Reactions of Nitroaromatic and Nitrogen Heterocyclic Compounds on Granular Activated Carbon (GAC) Surfaces: Enhancement of GAC Adsorption in Natural and Engineered Environmental Systems
Investigators: Schlautman, Mark , Herbert, Bruce , Karanfil, Tanju
Institution: Clemson University , Texas A & M University
EPA Project Officer: Krishnan, Bala S.
Project Period: September 1, 2000 through August 31, 2004
RFA: Gulf Coast Hazardous Substance Research Center (Lamar University) (1996)
Research Category: Hazardous Waste/Remediation , Targeted Research
Description:
Objective:Aromatic and heterocyclic nitrogen-containing compounds (e.g., nitroaromatic compounds, NACs; aromatic amines, AAs; triazines and other nitrogen-containing heterocyclic compounds, NCHCs) comprise an important class of environmental contaminants because of their suspected carcinogeneity and toxic effects on human health. NACs, AAs and NCHCs are produced and/or used in large quantities in ammunition plants, textile industries, herbicide production and agricultural areas. New and effective treatment technologies have to be developed for ex-situ treatment applications as well as for in-situ remediation applications to meet our increasingly stringent water quality standards and to reduce associated environmental risks of NACs and NCHCs because of their ineffective removal by conventional treatment processes. Granular activated carbon (GAC) adsorption has emerged as a viable treatment technology for removing these synthetic organic contaminants from water. In particular, the EPA has designated GAC adsorption as the best available technology for treating drinking water sources contaminated by organic contaminants. Economic design and effective application of a GAC adsorption system for target contaminant removal require two fundamental types of information: (1) sorption characteristics (i.e., extent and rate) of the target compound by GAC and (2) the impact of treatment and/or remediation conditions, particularly the background water matrix, on those characteristics. Another important phenomenon to be considered is the potential for organic compound transformation(s) of organic compounds on GAC surfaces. Investigation of the potential transformation pathways such as hydrolysis, oxidation/reduction or polymerization is essential to obtain a clear understanding of the fate of the target compound during GAC adsorption and better facilitate its appraisal as an effective and reliable treatment process. Currently, our knowledge of all these aspects of NAC and NCHC removal by GAC is limited.Sorption-initiated chemical reactions may play an important role in the removal of NACs and NCHCs from contaminated waters in in-situ and ex-situ engineered GAC treatment systems. Because of the relatively-high cost of activated carbon, a small increase in target compound removal efficiencies can lead to significant decreases in the operating costs of GAC treatment systems. Therefore, the principal objectives of this project are to gain a better understanding of the sorption and abiotic chemical transformations of NACs and NCHCs on GAC surfaces, to elucidate the relative roles and significance of solution chemistry parameters (e.g., pH, dissolved oxygen [DO], background dissolved organic materials [DOMs]) on these processes, and to develop novel approaches for the practical application of these reactions in GAC treatment/remediation systems.
Summary/Accomplishments (Outputs/Outcomes):The removal of selected target compounds, namely phenol, o-nitrophenol (ONP), 2,4-dinitrophenol (DNP), and 2,4-dinitrotoluene (DNT), from water by virgin F400 GAC (Calgon Corporation) was examined for two different pH conditions (4 and 7.5) and two different dissolved oxygen conditions (oxic and anoxic). The initial concentrations of phenol, ONP, and DNP were 1.0 mM (94, 139, and 184 mg/L, respectively) and that of DNT was 0.68 mM (124 mg/L). Each target compound was contacted with the GAC (mesh size 230/325) in 40 mL amber vials for 4 weeks. After this contact time, each sample vial was centrifuged and aliquots were taken for analysis on a Hewlett Packard gas chromatograph with mass selective detection (GCD).All target compound removals were fitted well by using the Freundlich isotherm (R2 0.87). Phenol sorption capacities (that is, KF in the Freundlich isotherm) at pH 7.5 were larger than that at pH 4 under both oxic and anoxic conditions. However, sorption capacities of ONP, DNP, and DNT slightly decreased with pH increasing from 4 to 7.5). The presence of dissolved oxygen (i.e., oxic condition resulting from air-saturated solutions) greatly increased the removal of phenol and DNP relative to the absence of oxygen (i.e., experiments conducted in an anaerobic chamber), but did not significantly affect the removal of ONP and DNT. The F400 GAC was contacted with strong reductants (i.e., Fe(II) and dithionite) prior to target compound removal experiments to test whether this pretreatment could improve the sorption characteristics for the target compounds. For this, 5 g GAC (mesh size 230/325) was pretreated by contacting 250 mL of 200 mM Na2S2O4 (dithionite-pretreated) or Fe(NH4)2(SO4) 6H2O (Fe(II)-pretreated) for 1 day in an anaerobic chamber to prevent the reductants from being oxidized by oxygen. After 1-day contact, the GAC was washed with 200 mL anaerobically-prepared distilled, deionized water (DDW) five times, and reductant concentrations remaining in the supernatant (or DDW washing) from each step were checked using Cr(VI). The amounts of reductant remaining in the supernatant or present in the DDW washes proved to be negligible by this test. The GAC was then centrifuged, dried by the ambient gas in the anaerobic chamber, and stored in a desiccator placed in the chamber until used. GAC pretreatment with strong reductants [Fe(II) or dithionite] resulted in minor differences in target compound removal relative to the virgin carbon; however, the differences observed have not been dramatic enough to warrant giving GAC pretreatment by reductants a high priority. In general, pretreatment of GAC deteriorated the sorption capacity of phenol but improved that of ONP. The effect of pretreatment on DNP removal was a little more complicated. Pretreatment improved removal of DNP at pH 4 under oxic conditions and at both pH values under anoxic conditions, while at pH 7.5 under the oxic condition DNP removal was slightly lower versus the virgin GAC. Sorption rate and extraction experiments were performed for phenol, DNP and ONP under oxic and anoxic conditions at pH 4. Phenol removal from solution was similar for both oxygen conditions up to approximately 10 hr, with the removal under both conditions being very fast initially and before becoming slower with increasing time. Equilibrium concentrations in the aqueous phase were obtained within one and three weeks under anoxic and oxic conditions, respectively. Based on extraction results, the slower equilibration time in the presence of dissolved oxygen (DO) was likely due to chemical reactions other than sorption that occurred on the GAC surface. DNP removal from solution was also observed to be fast at initial stages under both oxic and anoxic conditions. After approximately 12 hr, DNP concentrations changed very slowly and equilibrium appeared to be reached within 24 hr in the absence of DO. Conversely, in the presence of DO, DNP concentrations in the aqueous phase continually decreased with increasing contact time until an apparent equilibrium was reached at approximately 3 weeks. Similarly to the isotherm experiments, DNP removal in the presence of DO was better than in the absence of DO. However, DNP removal was not strictly correlated with extraction efficiencies because for both oxygen conditions the efficiencies decreased with increasing contact time. For the anoxic experiments in particular, this suggests that the decrease in extraction efficiencies is not due to oxidative coupling reactions (i.e., polymerization) on the GAC surface. Alternative possibilities for the decreasing extraction efficiencies may be reductive reactions on GAC surfaces, stronger sorption complexes being formed with time, and/or DNP diffusion deeper into the GAC pores. Preloading of GAC with humic acid, a representative background dissolved organic material (DOM), was conducted to investigate the impacts of DOM on target compound sorption. As expected, the removal of phenol and DNT deteriorated for the preloaded GAC. Results from the first two years of this GCHSRC-supported work showed that preloading of GAC with naturally-occurring dissolved organic materials (DOMs) had a significant impact on the removal of the target organic compounds from contaminated waters. Therefore, work in the latter stages of this project focused on the use of an alternative adsorbent to GAC, namely, activated carbon fibers (ACFs). ACFs show great promise in overcoming some of the limitations of GAC, particularly with respect to DOM preloading. They also tend to exhibit faster rates of contaminant removal from water than typical GAC adsorbents. The adsorption of a series of polymers and ultrafiltration (UF) size fractions of a DOM by selected GACs and ACFs was examined. By using different sizes of polymers it was possible to change the size of the molecules without changing the chemical composition of adsorbate, thereby, allowing the role of solute size on adsorption to be investigated. UF fractions allowed the investigation of the behavior of different size components within a heterogeneous DOM mixture. Commercially available ACFs having narrow and uniform pore size distributions were used to investigate the interactions in different regions of activated carbons pores. To relate the results of the fibers to carbons, experiments were also conducted using different GACS. Adsorption of the anionic and nonionic polymers by the ACFs and GACs clearly showed the competition existing between hydrophobic interactions (i.e., tendency to drive larger molecular weight (MW) molecules from solution) and size exclusion effects (i.e., relative sizes of adsorbent pores and sorbate molecular configurations). In general, size exclusion effects proved to be more important for the anionic polymer than for the nonionic polymer. The UF-fractionated DOM showed similar adsorption tendencies as did the anionic polymer. For example, the extent of uptake of both solutes decreased systematically with increasing MW for all GACs and ACFs tested. These preliminary results must be viewed with some caution, however, because of the known differences existing between naturally-occurring DOMs and model anionic macromolecules. For example, each MW of the anionic macromolecule has a very narrow distribution and similar chemistries, whereas the DOM was fractionated into size classes with a much wider range of physical, and possibly chemical, differences.
Journal Articles on this Report: 2 Displayed | Download in RIS Format
| Other subproject views: | All 6 publications | 2 publications in selected types | All 2 journal articles |
| Other center views: | All 472 publications | 140 publications in selected types | All 123 journal articles |
| Type | Citation | ||
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Karanfil T, Schlautman, MA, Kilduff JE, Weber Jr. WJ. Adsorption of organic macromolecules by granular activated carbon .2. Influence of molecular properties under anoxic solution conditions. Environmental Science & Technology 1996; 30(7): 2195-2207. |
R826694C636 (Final) |
not available |
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Karanfil T, Kilduff JE, Schlautman MA, Weber Jr WJ. Adsorption of organic macromolecules by granular activated carbon. 1. Influence of molecular properties under anoxic solution conditions. Environmental Science & Technology 1996;30(7):2187-2194. |
R826694C636 (Final) |
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drinking water treatment, wastewater treatment, catalysis. , Water, INTERNATIONAL COOPERATION, Scientific Discipline, Waste, RFA, Remediation, Hazardous Waste, Environmental Engineering, Environmental Chemistry, Chemistry and Materials Science, Contaminated Sediments, Groundwater remediation, Hazardous, heavy metal contamination, nitrogen heterocyclic compounds, chemical transport, groundwater hydrology models, nitroaromatic compounds, groundwater, granular activated carbon, contaminant transport, pesticides, contaminated soil, groundwater contamination, contaminated groundwater, sediment treatment, chemical contaminants
Progress and Final Reports:
Original Abstract
Main Center Abstract and Reports:
R828598 Gulf Coast HSRC (Lamar)
Subprojects under this Center:
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R822721C529 Environmentally Acceptable Endpoints: Risk Based Remediation Using Bioremediation
R822721C552 Degradative Solidification/Stabilization Technology for Chlorinated Hydrocarbons
R822721C569 Treatment and Product Recovery: Supercritical Water Oxidation of Nylon Monomer Manufacturing Waste
R822721C620 Colloidal Fouling of Membranes: Implications in the Treatment of Textile Dye Wastes and Water Reuse
R822721C626 Catalytic Hydroprocessing of Chlorinated Organics
R822721C627 The Interaction of Microbial Activity and Zero Valent Iron Permeable Barrier Technology
R822721C630 Microbial Cometabolism of Recalcitrant Chemicals in Contaminated Air Streams
R822721C633 Catalyst Lifetime Studies for Chlorocarbon Steam Reforming
R822721C635 Electrokinetic/Surfactant-Enhanced Remediation of Hydrophobic Pollutants in Low Permeability Subsurface Environments
R822721C636 Transformation Reactions of Nitroaromatic and Nitrogen Heterocyclic Compounds on Granular Activated Carbon (GAC) Surfaces: Enhancement of GAC Adsorption in Natural and Engineered Environmental Systems
R822721C640 Environmentally Friendly Organic Synthesis in Supercritical Fluids
R822721C645 Development and Evaluation of an Integrated Model to Facilitate Risk-Based Corrective Action at Superfund Sites
R822721C651 Adjustable Biopolymer Chelators for Cadmium, Lead and Mercury
R822721C653 New Electrochemically Smart Catalysts for Hazardous Waste Management and Development of Capillary Electrophoresis for Analysis of their Products
R822721C655 Soil Sampling in South Alabama Oil Fields
R822721C659 Subsurface Contamination Site Characterization via a Computer-Aided Visual Tool
R822721C661 New Insoluble supports for Protein Immobilization for Use in Metalloprotein Affinity Metal Chromatography
R822721C663 Soil Remediation with Ultra-High-Efficiency Hydrocyclones
R822721C669 Solid Acid Catalyzed Alkylation in Supercritical Fluids
R822721C679 Regeneration/Reactivation of Carbon Adsorbents by Radio Frequency (RF) Induction Heating
R822721C687 Improved Halogen Resistance of Catalytic Oxidation
R822721C696 Phytoremediation and Bioremediation of Land Contaminated By PAHs, PCBs, and TNT
R822721C697 Fundamental and Kinetic Investigation of Sorbent Technology for Optimum Mercury Emission Control
R822721C700 Effects of Natural and Cyclic Variations on Contaminant Fate and Transport
R822721C703 Enhancement of DNAPL Dissolution Rates by Dechlorinating Anaerobes
R826694C620 Colloidal Fouling of Membranes: Implications in the Treatment of Textile Dye Wastes and Water Reuse
R826694C625 Enhanced Treatment of DNAPLs Contaminated Soils and Groundwater Using Biosurfactants: In-Situ Bioremediation
R826694C626 Catalytic Hydroprocessing of Chlorinated Wastes
R826694C627 The Interaction of Microbial Activity and Zero Valent Iron Permeable Barrier Technology
R826694C629 Biofiltration of BTEX in Petroleum-Contaminated Soil Remediation Off-Gas
R826694C630 Microbial Cometabolism of Recalcitrant Chemicals in Contaminated Air Streams
R826694C633 Catalyst Lifetime Studies for Chlorocarbon Steam Reforming
R826694C635 Electrokinetic/Surfactant-Enhanced Remediation of Hydrophobic Pollutants in Low Permeability Subsurface Environments
R826694C636 Transformation Reactions of Nitroaromatic and Nitrogen Heterocyclic Compounds on Granular Activated Carbon (GAC) Surfaces: Enhancement of GAC Adsorption in Natural and Engineered Environmental Systems
R826694C640 Environmentally Friendly Organic Synthesis in Supercritical Fluids
R826694C645 Development and Evaluation of an Integrated Model to Facilitate Risk-Based Corrective Action at Superfund Sites
R826694C651 Adjustable Biopolymer Chelators for Cadmium, Lead, and Mercury Remeidation
R826694C659 Subsurface Contamination Site characterization Via a Computer-Aided Visual Tool
R826694C661 New Insoluble supports for Protein Immobilization for Use in Metalloprotein Affinity Metal Chromatography
R826694C669 Solid Acid Catalyzed Alkylation in Supercritical Reaction Media
R826694C679 Regeneration and Reactivation of Carbon Adsorbents by Radio Frequency Induction Heating
R826694C696 Phytoremediation and Bioremediation of Land Contaminated By PAHs, PCBs, and TNT
R826694C697 Fundamental and Kinetic Investigation of Sorbent Technology for Optimum Mercury Emission Control
R826694C700 Effects of Natural Cyclic Variations on Contaminated Fate and Transport
R826694C703 Enhancement of DNAPL Dissolution Rates by Dechlorinating Anaerobes
R826694C705 A Pilot Plant for Producing Mixed Ketones from Waste Biomass
R826694C722 The Effects of an Oily-Phase on VOC Emissions from Industrial Wastewater
R826694C724 Mercury Removal from Stack Gas by Aqueous Scrubbing
R826694C725 Transport, Fate and Risk Implications of Environmentally Acceptable Endpoint Decisions
R826694C731 Development and Application of a Real-Time Optical Sensor for Atmospheric Formaldehyde
R826694C734 An Advanced System for Pollution Prevention in Chemical Complexes
R828598C001 Field Study Abstract: A Model of Ambient Air Pollution in Southeast Texas Using Artificial Neural Network Technology
R828598C002 Hollow Fiber Membrane Bioreactors for Treating Water and Air Streams Contaminated with Chlorinated Solvents
R828598C003 Fugitive Emissions of Hazardous Air Pollutants from On-Site Industrial Sewers
R828598C004 Biofiltration Technology Development
R828598C005 A Risk-Based Decision Analysis Approach for Aquifers Contaminated with DNAPLs
R828598C006 In-Situ Remediation for Contaminated Soils Using Prefabricated Vertical Drains
R828598C007 Membrane Technology Selection System for the Metal Finishing Industry
R828598C008 Sequential Environments for Enhanced Bioremediation of Chlorinated Aliphatic Hydrocarbons
R828598C009 Waste Minimization in the Magnetic Tape Industry: Waterborne Coating Formulations for Magnetic Tape Manufacture
R828598C010 Soil Remediation by Agglomeration with Petroleum Coke
R828598C011 Recovery of Dilute Phosphoric Acid in Waste Streams Using Waste Gas Ammonia: The Regenerative MAP/DAP Process
R828598C012 Stochastic Risk Assessment for Bioremediation
R828598C013 Selective Removal of Heavy Metals from Wastewater by Chelation in Supercritical Fluids
R828598C014 Optimization of Treatment Technologies for Detoxification of PCB Contaminated Soils
R828598C015 Wastewater Remediation by Catalytic Wet Oxidation
R828598C016 Permanence of Metals Containment in Solidified and Stabilized Wastes
R828598C017 Combustion Enhancement by Radial Jet Reattachment - Low Generation of Hazardous Gases and High Thermal Efficiency
R828598C018 A Process To Convert Industrial Biosludge and Paper Fines to Mixed Alcohol Fuels
R828598C019 Homogeneous Catalysis in Supercritical Carbon Dioxide
R828598C020 Ultrasonic Enhancement of the Removal of Heavy Metals
R828598C021 The Binding Chemistry and Leaching Mechanisms of Advanced Solidification/Stabilization Systems for Hazardous Waste Management
R828598C022 Development of an Air-Stripping and UV/H2O2 Oxidation Integrated Process To Treat a Chloro-Hydrocarbon-Contaminated Ground Water
R828598C023 A Comparative Study of Siting Opposition in Two Counties
R828598C024 Sonochemical Treatment of Hazardous Organic Compounds II: Process Optimization and Pathway Studies
R828598C025 Laser Diagnostics of the Combustion Process within a Rotary Kiln Incinerator
R828598C026 Use of Inorganic Ion Exchangers for Hazardous Waste Remediation
R828598C027 Kaolinite Sorbent for the Removal of Heavy Metals from Incinerated Lubricating Oils
R828598C028 Destruction of Chlorinated Hydrocarbons in Process Streams Using Catalytic Steam Reforming
R828598C029 Integrated Process Treatment Train (Bioremediation {Aerobic/Anaerobic} and Immobilization) for Texas Soils Contaminated with Combined Hazardous Wastes
R828598C030 Photo-Oxidation by H2O2/VisUV of Off-Gas Atmospheric Emissions from Industrial and Environmental Remediation Sources
R828598C031 Concentrated Halide Extraction and Recovery of Lead from Soil
R828598C032 Biodegradable Surfactant for Underground Chlorinated Solvent Remediation
R828598C033 A Software Guidance System for Choosing Analytical Subsurface Fate and Transport Models Including a Library of Computer Solutions for the Analytical Models
R828598C034 Hydrodynamic Modeling of Leachate Recirculating Landfill
R828598C035 Measurement of Oxygen Transfer Rate in Soil Matrices
R828598C036 Sorbent Technology for Multipollutant Control During Fluidized Bed Incineration
R828598C037 Pollution Prevention by Process Modification Using On-Line Optimization
R828598C038 Pollution Prevention by Process Modification
R828598C039 Water Solubility and Henry's Law Constant
R828598C040 Transferring Technical Information on Hazardous Substance Research by Publishing on the World Wide Web
R828598C041 Stress Protein Responses to Multiple Metal Exposure in Grass Shrimp
R828598C042 Life-Cycle Environmental Costing for Managing Pollution Prevention in the Chemical and Petroleum Refining Industries: A Cross-Border Approach
R828598C687 Improved Halogen Resistance of Catalytic Oxidation Through Efficient Catalyst Testing
R828598C696 Phytoremediation and Bioremediation of Land Contaminated By PAHs, PCBs, and TNT
R828598C697 Fundamental and Kinetic Investigation of Sorbent Technology for Optimum Mercury Emission Control
R828598C700 Effects of Natural Cyclic Variations on Contaminated Fate and Transport
R828598C703 Enhancement of DNAPL Dissolution Rates by Dechlorinating Anaerobes
R828598C705 A Pilot Plant for Producing Mixed Ketones from Waste Biomass
R828598C722 The Effects of an Oily-Phase on VOC Emissions from Industrial Wastewater
R828598C724 Mercury Removal from Stack Gas by Aqueous Scrubbing
R828598C725 Transport, Fate and Risk Implications of Environmentally Acceptable Endpoint Decisions
R828598C731 Development and Application of a Real Time Optical Sensor for Atmospheric Formaldehyde
R828598C734 An Advanced System for Pollution Prevention in Chemical Complexes
R828598C743 Field Demonstration of Ultrasound Enhancement of Permeable Treatment Walls
R828598C744 Optical Fibers Coated With Titania Membrane/UV-Generating Crystal in a Distributed-Light Photoreactor for VOC Oxidation
R828598C749 Characterization and Modeling of Indoor Particulate Contaminants In a Heavily Industrialized Community
R828598C753 Adsolubilization and Photocatalysis in a Semiconducting Monolithic Reactor for Wastewater Treatment
R828598C754 Remote Detection of Gas Emissions in Industrial Processes
R828598C759 Searching for Optimum Composition of Phosphogypsum: Fly ash: Cement Composites for Oyster Culch Materials
R828598C761 Development of a Phytologically-Based Biosorptive Water Treatment Process
R828598C766 Chlorinated Solvent Impact and Remediation Strategies for the Dry Cleaning Industry
R828598C769 Soil/Sediment Remediation by Hot Water Extraction Combined with In-Situ Wet Oxidation
R828598C771 Fluoracrylate Polymer Supported Ligands as Catalysts for Environmentally Benign Synthesis in Supercritical Fluids
R828598C774 The Feasibility of Electrophoretic Repair of Impoundment Leaks
R828598C777 Surfactant Enhanced Photo-oxidation of Wastewaters
R828598C778 Stationary Power Generation Via Solid Oxide Fuel Cells: A Response to Pollution and Global Warming
R828598C786 Photocatalytic Recovery of Sulfur and Hydrogen From Hydrogen Sulfide
R828598C787 Biosurfactant Produced from Used Vegetable Oil for removal of Metals From Wastewaters and Soils
R828598C789 Genetic Engineering of Enzymatic Cyanide Clearance
R828598C791 Characterizing the Intrinsic Remediation of MTBE at Field Sites
R828598C799 Simultaneous Water Conservation/Recycling/Reuse and Waste Reduction in Semiconductor Manufacturing
R828598C801 Building Defined Mixed Cultures To Biodegrade Diverse Mixtures Of Chlorinated Solvents
R828598C802 Engineering of Nanocrystal Based Catalytic Materials for Hydroprocessing of Halogenated Organics
R828598C807 Commercial Demonstration of Hydrogen Peroxide Injection to Control NOx Emissions from Combustion Sources
R828598C809 Evaluating Source Grouting and ORC for Remediating MTBE Sites
R828598C810 Application of Total Cost Assessment To Process Design In the Chemical Industry
R828598C846 Quantitative Demonstration of Source-Zone Bioremediation in A Field-Scale Experimental Controlled Release System
R831276C001 DNAPL Source Control by Reductive Dechlorination with Fe(II)
R831276C002 Arsenic Removal and Stabilization with Synthesized Pyrite
R831276C003 A Large-Scale Experimental Investigation of the Impact of Ethanol on Groundwater Contamination
R831276C004 Visible-Light-Responsive Titania Modified with Aerogel/Ferroelectric Optical Materials for VOC Oxidation
R831276C005 Development of a Microwave-Induced On-Site Regeneration Technology for Advancing the Control of Mercury and VOC Emissions Employing Activated Carbon
R831276C006 Pollution Prevention through Functionality Tracking and Property Integration
R831276C007 Compact Nephelometer System for On-Line Monitoring of Particulate Matter Emissions
R831276C008 Effect of Pitting Corrosion Promoters on the Treatment of Waters Contaminated with a Nitroaromatic Compounds Using Integrated Reductive/Oxidative Processes
R831276C009 Linear Polymer Chain and Bioengineered Chelators for Metals Remediation
R831276C010 Treatment of Perchlorate Contaminated Water Using a Combined Biotic/Abiotic Process
R831276C011 Rapid Determination of Microbial Pathways for Pollutant Degradation
R831276C012 Simulations of the Emission, Transport, Chemistry and Deposition of Atmospheric Mercury in the Upper Gulf Coast Region
R831276C013 Reduction of Environmental Impact and Improvement of Intrinsic Security in Unsteady-state
R831276C014 Integrated Chemical Complex and Cogeneration Analysis System: Greenhouse Gas Management and Pollution Prevention Solutions
R831276C015 Improved Combustion Catalysts for NOx Emission Reduction
R831276C016 A Large-Scale Experimental Investigation of the Impact of Ethanol on Groundwater Contamination
R831276C017 Minimization of Hazardous Ion-Exchange Brine Waste by Biological Treatment of Perchlorate and Nitrate to Allow Brine Recycle
R831276C018 Integrated Chemical Complex and Cogeneration Analysis System: Greenhouse Gas Management and Pollution Prevention Solutions