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Articles 991 - 1020 of 1102

Full-Text Articles in Chemistry

Optimization Of Palladium-Catalyzed In Situ Destruction Of Trichloroethylene-Contaminated Groundwater Using A Genetic Algorithm, Manuel Fernandez Mar 2001

Optimization Of Palladium-Catalyzed In Situ Destruction Of Trichloroethylene-Contaminated Groundwater Using A Genetic Algorithm, Manuel Fernandez

Theses and Dissertations

Conventional technologies for the treatment of groundwater contaminated with chlorinated solvents have limitations that have motivated development of innovative technologies. One such technology currently under development involves using palladium-on-alumina (Pd/Al) as a catalyst to promote dechlorination. Pd/Al catalyst may be used in-well as part of a re-circulating horizontal flow treatment well (HFTW) system. An HFTW system involves two or more dual-screened wells, with in-well reactors, to capture and treat contaminated groundwater without the need to pump the water to the surface. In this study, objective and fitness functions, based on system costs and TCE concentration requirements, were developed to optimize …


Dissolution Of Chromium From Inhalable Primer Paint Particles Into A Simulated Lung Fluid, David A. Kauth Mar 2001

Dissolution Of Chromium From Inhalable Primer Paint Particles Into A Simulated Lung Fluid, David A. Kauth

Theses and Dissertations

The use of chromate as a corrosion inhibitor in primer paint is an essential component for the protection of aluminum-skinned aircraft and the primary source of hexavalent chromium (Cr (VI)) exposure to USAF aircraft painters. The objective of this research was to quantify the dissolution of chromate from freshly sprayed paint particles into a simulated lung fluid (SLF). Two primer paints were sprayed with a paint spray gun to generate overspray particles for collection into impingers filled with SLF. Particles were allowed to soak in SLF for 24 and 48 hours and then the particles were removed by centrifugation. The …


Report Of The State Nuclear Safety Advisor Submitted To The Governor And 120th Legislature As Of January 15, 2001, Paula M. Craighead Jan 2001

Report Of The State Nuclear Safety Advisor Submitted To The Governor And 120th Legislature As Of January 15, 2001, Paula M. Craighead

Maine Collection

Report of the State Nuclear Safety Advisor submitted to the Governor and 120th Legislature As of January 15, 2001

Paula M. Craighead, State Nuclear Safety Advisor, Executive Department, Maine State Planning Office, Augusta, Maine, 2001.

Contents: Introduction and Executive Summary / I. Maine Yankee Decommissioning / II. Portsmouth Naval Shipyard (PNS) / III. Low-Level Radioactive Waste (LLRW) / IV. High Level Radioactive Waste / V. Transport Routes and Safety Response / VI. Shipments / VII. Status of Federal and State Legal and Administrative Proceedings / References and Resources / Glossary


Use Of Py-Gc/Ms Analysis Techniques In Animal Waste Management: A Preliminary Survey Of Dairy Manures, Daniel L. Vaughn, Michael A. Kruge Jan 2001

Use Of Py-Gc/Ms Analysis Techniques In Animal Waste Management: A Preliminary Survey Of Dairy Manures, Daniel L. Vaughn, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The increasing practice of industrial-scale agriculture tends to concentrate large masses of animal waste in relatively compact areas, potentially leading to excessive release of polluting nutrients into waterways during major storms. Anaerobic treatment conditions are generally favored to conserve nitrate N as an agricultural commodity. However, overall N contents in waste are often in excess of crop fertilization needs: storing excess N in soluble nitrate form increases pollution potential. Thus the perceived needs of agriculture and society-at-large become at odds. Organic nitrogen forms (e.g., proteins) are more environmentally stable and are less subject to unintentional release. Although U.S. farmers tend …


Auditing And Biological Treatment Of Oleochemical Industry Waste, Fauziah Shahul Hamid Jan 2001

Auditing And Biological Treatment Of Oleochemical Industry Waste, Fauziah Shahul Hamid

Student Works (2000-2009)

The utilization of renewable resources particularly from plant-based industries, such as, in the oleochemical sector makes it possible for further expansion of down-stream process products. However, to remain competitive the pollution generated from this industry should not be taken lightly. Implementation of cleaner technology into the oleochemical process will increase the efficiency of resource utilization of the industry, concurrently reducing quantity of waste generated. Waste audit conducted at Cognis Oleochemical (M) (COM) Sdn. Bhd. indicated that the major process-wastes generated by the facility were glycerol residue (GR) from Cognis Rika (M) Sdn. Bhd. (CRM) and wastewater sludge (WWS) from COM …


Municipal Waste Characteristics And Management In Pantai Dalam, Kuala Lumpur, Ratanam Andythaven Jan 2001

Municipal Waste Characteristics And Management In Pantai Dalam, Kuala Lumpur, Ratanam Andythaven

Student Works (2000-2009)

The primary purpose of this research was to study comprehensively the municipal waste generation (rate, quantity), waste characterization including (physical, chemical and biological parameters), heavy metal content, waste recovery and recycling, and socio economic aspects of municipal solid waste (MSW) generation and management in Taman Bukit Angkasa, Pantai Dalam, Kuala Lumpur and the surrounding areas. The waste characterization and management was determined with actual field observations coupled with questionnaire survey from a random sample of 250 households (200 flats houses, 25 long houses and 25 squatter residences). The quantification and other parameters (heavy metals, water extractable nutrients, nitrogen, pH, acidity, …


Application Of Gc-Fid And Gc-Ms In The Analysis Of Residue Level Of Phthalate Esters Along The Klang River, Maheschandar Biaspal Jan 2001

Application Of Gc-Fid And Gc-Ms In The Analysis Of Residue Level Of Phthalate Esters Along The Klang River, Maheschandar Biaspal

Student Works (2000-2009)

"Phthalate Esters" ("PEs") are considered as major industrial wastes that can cause pollution in the river water. A study of determination of the PEs in the Klang River water by the application of "Gas Chromatography'' ("GC'') with "Flame-Ionisation Detector" ("FID") will be carried out in this project. "Mass-Selective Detector" ("GC-MSD") will be used in the identification of phthalates compoW1d. A BP-5 non-polar capillary column will be used for the river water analysis. The river water will first be separated by a liquid-liquid extraction with an organic solvent. Toe extracts will then be subjected to a clean-up procedure to separate out …


Characterization Of Solvent-Extractable Hydrocarbons From Airborne Particulates And Street Dust Of Kuala Lumpur, Nasr Yousef M. J. Omar Jan 2001

Characterization Of Solvent-Extractable Hydrocarbons From Airborne Particulates And Street Dust Of Kuala Lumpur, Nasr Yousef M. J. Omar

Student Works (2000-2009)

The solvent-extractable hydrocarbons were identified in PM 10 airborne particles and roadside soil particles collected at eight locations in the city center and the suburb of Kuala Lumpur, Malaysia during the period from November 1998 to January 1999. Airborne particles were collected using high-volume PM1o sampler on glass fiber filters over 24 h average sampling period. After ultrasonic agitation with dichloromethane, the extracts were concentrated and fractionated on an alumina-silica column into three major fractions (aliphatics, aromatics and polar compounds). The aliphatics and aromatics fractions were then subjected to gas chromatography-mass spectrometric (GCMS) analysis. The major hydrocarbons identified in these …


Composition And Anaerobic Digestion Of Single And Combined Organic Fractions Of Municipal Solid Waste Of Dar Es Salaam, A K Kivaisi, J Mukisa Dec 2000

Composition And Anaerobic Digestion Of Single And Combined Organic Fractions Of Municipal Solid Waste Of Dar Es Salaam, A K Kivaisi, J Mukisa

Tanzania Journal of Science

The composition of major categories of municipal solid waste (MSW) of Dar es salaam city was determined. Food remains and vegetable matter constituted 80-90% of the categories. Organic fractions of the individual categories contained 18-20 % total solid (TS), 30-50 % (dry weight) total fibre and 1-1.3 % nitrogen. The assorted organic fractions were tested for anaerobic conversion into biogas at 55°C in batch cultures for 14 days with a mixed population of microorganisms. At a substrate concentration of 6-8 g volatile solids per litre fermenter volume (g VS l-1 FV) individual fractions were degraded by 51-75% and gave methane …


Biogeochemistry And Contaminant Geochemistry Of Marine And Estuarine Sediments, New Haven, Connecticut (Usa), Michael A. Kruge, Gaboury Benoit Nov 2000

Biogeochemistry And Contaminant Geochemistry Of Marine And Estuarine Sediments, New Haven, Connecticut (Usa), Michael A. Kruge, Gaboury Benoit

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The urbanized shore areas of Long Island Sound in the vicinity of New Haven, Connecticut (USA) have a long history of exposure to point and non-point sources of pollution, New Haven having been one of the birthplaces of the industrial revolution. As an unintended consequence of such activities, the region's sedimentary systems have incorporated a complex mixture of organic and inorganic contaminants. With its long and varied pollution history and the multiplicity of sedimentary environments (fluvial, estuarine, intertidal, marsh, etc.) present in a compact geographical area, the region is ideal natural laboratory for field testing new contamination assessment techniques. The …


Risk Assessments For Chemical Stockpile Incinerators: Is The Supporting Guidance Adequate, Lawrence V. Tannenbaum Sep 2000

Risk Assessments For Chemical Stockpile Incinerators: Is The Supporting Guidance Adequate, Lawrence V. Tannenbaum

RISK: Health, Safety & Environment (1990-2002)

The author identifies potential deficiencies in guidance used in the United States for risk assessments of chemical weapons incinerators.


Modeling Chlorinated Ethene Removal In Constructed Wetlands: A System Dynamics Approach, Colby D. Hoefar Mar 2000

Modeling Chlorinated Ethene Removal In Constructed Wetlands: A System Dynamics Approach, Colby D. Hoefar

Theses and Dissertations

The purpose of this study is to gain understanding of the dynamics of the processes that degrade Perchloroethene (PCE) to ethylene, or carbon dioxide (CO2), within the confines of a constructed wetland. A system dynamics approach will be used. This model is focused on identifying and optimizing the naturally occurring processes in stratified wetland sediment that reduce mass, toxicity, mobility, volume or concentration of contaminants in groundwater. Contaminant fate and transport within a wetland system is extremely complex and the mechanisms that drive wetland behavior are dynamic. Confidence in the model was built through verification and testing. Reasonable …


In Situ Treatment Of Chlorinated Ethene-Contaminated Groundwater Using Horizontal Flow Treatment Wells, Derek R. Ferland Mar 2000

In Situ Treatment Of Chlorinated Ethene-Contaminated Groundwater Using Horizontal Flow Treatment Wells, Derek R. Ferland

Theses and Dissertations

The limitations of conventional containment technologies for groundwater contaminated with chlorinated solvents have motivated development of innovative technologies to achieve national groundwater remediation objectives. One inn9vative technology that is currently under development involves metal reductants or catalysts to chemically destroy the dissolved chlorinated solvent. Models are important tools that can be used to help transition this technology to the field. Model studies can be used to gain understanding about the technology, help determine when the prospective technology might work for a given site, and design full-scale field applications.


Parameters Influencing Sediments Resuspension And The Link To Sorption Of Inorganic Compounds, Eid A. Alkhatib, Keith Castor Jan 2000

Parameters Influencing Sediments Resuspension And The Link To Sorption Of Inorganic Compounds, Eid A. Alkhatib, Keith Castor

Chemistry & Physics Faculty Publications

In the aquatic environment, the accumulation of chemicalcontaminants by sediments poses a potential threat to endemiclife forms and drinking water resources. Trace metals such asCd, Cu, Cr, Ni, Pb, and toxic organic compounds, are among awide variety of contaminants having an affinity for sediments.In this study, experiments were performed simulating sedimentresuspension in the lower Housatonic River, Connecticut, using aParticle Entrainment Simulator. Analyses of grain sizedistributions, porosities and total organic contents of thesediments suggested that these parameters influence theredistribution and entrainment of settleable solids in the watercolumn. These findings were established by evaluating the impactof one parameter on sediment resuspension as …


Analysis Of Selected Trace Metals In Water Using Differential Pulse Polarography And Anodic Stripping Voltammetry, Kar Yi Tong Jan 2000

Analysis Of Selected Trace Metals In Water Using Differential Pulse Polarography And Anodic Stripping Voltammetry, Kar Yi Tong

Student Works (2000-2009)

In this project, two types of the electroanalytical methods have been studied, which are the Differential Pulse Polarography_ (DPP) and Differential Pulse Stripping Voltammetry (DPSV). The DPP mode is used to identify the half-wave potential for the metals, including the lead, cadmium, and zinc. The DPP mode is also used to determine the detection limits for the lead, cadmium, and zinc. Meanwhile, the DPSV mode is used to identify the half-wave potential for the metals. The optimum conditions for the DPSV has to be determined, in order to be used to determine the concentrations of the lead, cadmium, and zinc …


A Study Of Traffic Noise From Selected Urban And Suburban Areas, Savitri Ramiah Jan 2000

A Study Of Traffic Noise From Selected Urban And Suburban Areas, Savitri Ramiah

Student Works (2000-2009)

The main aim of this study is to determine the noise levels in selected urban and suburban roads and to compare the difference in traffic noise levels between these areas. 1be noise attenuated by noise barrier was also surveyed as a small portion of this study. Analysis of traffic noise was surveyed at five locations. Two locations were surveyed for the urban area and two locations for the suburban area and one location for noise barrier. The traffic volume for the duration of the survey was also recorded. Both day time and night time noise levels were studied. The survey …


Media Coverage Of Epa's Draft Dioxin Reassessment Report, Sharon M. Friedman, Megan A. Fitzpatrick, Brenda P. Egolf Jun 1999

Media Coverage Of Epa's Draft Dioxin Reassessment Report, Sharon M. Friedman, Megan A. Fitzpatrick, Brenda P. Egolf

RISK: Health, Safety & Environment (1990-2002)

Using content analysis, the authors examine the utility of news media in democratic decision making.


Novel Carbon-Carbon Bond Oxidative Cleavage Of Hexabenzyl-Hexaazaisowurtzitane By N-Buono And (Nh4)2ce(No3)6, Xiao-Pei Guan, Hong Yan, Jian-Guang Sun, Yong-Zhong Yu Mar 1999

Novel Carbon-Carbon Bond Oxidative Cleavage Of Hexabenzyl-Hexaazaisowurtzitane By N-Buono And (Nh4)2ce(No3)6, Xiao-Pei Guan, Hong Yan, Jian-Guang Sun, Yong-Zhong Yu

Publications and Research

Treatment of 2,4,6,8,10,12-hexabenzyl-2,4,6,8,10,12-hexaazatetracyclo-[5.5.0.05,9.03,11]dodecane with n-butyl nitrite or ammonium cerium nitrate results in novel C(1)-C(7) oxidative cleavage to give 1,3,4,5,7,8-hexabenzyl-cis-cisoid-cis-hexahydro-1H,5H-diimidazolinium[4,5-b:4′,5′-e]pyrazine dinitrate.


Bulletin 4357 - Fertilisers For Pastures On Sandy Soils Of The Swan Coastal Plain, K. W. Angell Mar 1999

Bulletin 4357 - Fertilisers For Pastures On Sandy Soils Of The Swan Coastal Plain, K. W. Angell

Bulletins 4000 -

When newly cleared for agriculture, the sandy soils of the Swan Coastal Plain were acutely deficient in phosphorus (P), nitrogen (N), and the trace elements copper ( Cu) and zinc (Zn) and sometimes molybdenum (Mo). Phosphorus deficiency was overcome by applying single superphosphate. Trace element deficiencies were overcome by adding Cu, Zn and Mo to superphosphate during manufacture, allowing P, Cu, Zn and Mo to be applied to the pasture in the one operation.

It was subsequently found that low sulphur (S) and potassium (K) were limiting production and persistence of subterranean clover-based pastures on the sandy soils of the …


Classification Of Explosives Transformation Products In Plant Tissue, Steven L. Larson, Robert P. Jones, Lynn Escalon, Don Parker Jan 1999

Classification Of Explosives Transformation Products In Plant Tissue, Steven L. Larson, Robert P. Jones, Lynn Escalon, Don Parker

United States Army Corps of Engineers, Omaha District

Explosives contamination in surface or groundwater used for the irrigation of food crops and phytoremediation of explosives-contaminated soil or water using plant-assisted biodegradation have brought about concerns as to the fate of explosives in plants. Liquid scintillation counting, high-performance liquid chromatography, and gel permeation chromatography were utilized to characterize explosives (hexahydro-1,3,5-trinitro-1,3,5-triazine and trinitrotoluene) and their metabolites in plant tissues obtained from three separate studies. Analyzing tissues of yellow nutsedge (Cyperus esculentus), corn (Zea mays), lettuce (Lacuta sativa), tomato (Lyopersicum esculentum), radish (Raphanus sativus), and parrot feather (Myriophyllum aquaticum) …


Molecular Organic Geochemistry Of New York Bight Sediments. Sources Of Biogenic Organic Matter And Polycyclic Aromatic Hydrocarbons, Michael A. Kruge Jan 1999

Molecular Organic Geochemistry Of New York Bight Sediments. Sources Of Biogenic Organic Matter And Polycyclic Aromatic Hydrocarbons, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

As part of a multidisciplinary evaluation of the environmental impact of waste disposal in the New York Bight, a preliminary effort was undertaken to assess the molecular geochemistry of its sedimentary organic matter (OM). For this initial phase of the study, samples were taken from two New York Bight cores collected outside the area of known dumping [in Sandy Hook Bay, NJ], to establish the environmental context for future work on sediments from within dumpsite zones. The method employed was flash pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), which is an organic microanalysis technique suitable for solid samples, in this case dried, raw …


Interagency Lake Mead And Las Vegas Wash Monitoring Program: Standard Operating Procedures Manual, Bureau Of Reclamation, City Of Henderson Water Reclamation Facility, City Of Las Vegas Water Pollution Control Facility, Clark County Sanitation District, Nevada, Southern Nevada Water Authority Oct 1998

Interagency Lake Mead And Las Vegas Wash Monitoring Program: Standard Operating Procedures Manual, Bureau Of Reclamation, City Of Henderson Water Reclamation Facility, City Of Las Vegas Water Pollution Control Facility, Clark County Sanitation District, Nevada, Southern Nevada Water Authority

Publications (WR)

A number of agencies sample Lake Mead and the Las Vegas Wash on a routine basis at several locations. In order to share and properly interpret the data, the Bureau of Reclamation, Southern Nevada Water Authority and the three Wastewater Treatment Facilities (City of Las Vegas, Clark County Sanitation District and City of Henderson) formed a committee to examine sampling and analytical protocols and to share information with the goal of maximizing the data quality. The group first met in April 1997. It was agreed that an effort should be made to discuss and compare specific sampling and analytical techniques …


Determination Of The N-Terminal Amino Acid Residues On Polypeptides In Secondary Wastewaters, Edward L. Creecy Jul 1998

Determination Of The N-Terminal Amino Acid Residues On Polypeptides In Secondary Wastewaters, Edward L. Creecy

Chemistry & Biochemistry Theses & Dissertations

The N-terminal amino acid residues on polypeptides and proteins were determined in wastewaters prior to chlorination. The terminal amino groups'ere first derivatized with the well known derivatizing agent dansyl chloride, and then the resulting dansyl amino acid hydrolyzed from the peptide chain by a propionic acid/ hydrochloric acid mixture. The resulting dansyl amino acids were then separated and detected using reversed phase high performance liquid chromatography with fluorescence detection. The majority of N-terminal residues detected were the more polar amino acids. Concentrations ranged from 1 x 10-10 to 3 x 10-7 moles/liter. It is suggested that the shorter …


Environmental And Botanical Controls On Peatification - A Comparative Study Of Two New Zealand Restiad Bogs Using Py-Gc/Ms, Petrography And Fungal Analysis, Tomasz K. Kuder, Michael A. Kruge, J C. Shearer, S L. Miller Jan 1998

Environmental And Botanical Controls On Peatification - A Comparative Study Of Two New Zealand Restiad Bogs Using Py-Gc/Ms, Petrography And Fungal Analysis, Tomasz K. Kuder, Michael A. Kruge, J C. Shearer, S L. Miller

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

This study shows that chemical properties of two restiad species, Empodisma minus and Sporadanthus traversii, may contribute to their success as peat-formers in a climate of the North Island of New Zealand which is not conducive to raised mire development. Unlike Sphagnum, the equivalent northern hemisphere peat-former, restiads possess lignin in their tissues. In addition, the presence of non-lignin polyphenols (including tannins and phenolic acids) in restiads may be an important factor in peat formation due to the allelopathic decay retardation. Patterns of degradation of plant biopolymers have been examined and the pathway of degradation of monocotyledons (loss …


A Molecular Evaluation Of Contaminants And Natural Organic Matter In Surface Sediments From Western Lake Ontario, Michael A. Kruge, Prasanta K. Mukhopadhyay, C.F. Michael Lewis Jan 1998

A Molecular Evaluation Of Contaminants And Natural Organic Matter In Surface Sediments From Western Lake Ontario, Michael A. Kruge, Prasanta K. Mukhopadhyay, C.F. Michael Lewis

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) analysis of bottom sediment from Lake Ontario was shown to be effective in assessing organic contaminants, especially attractive as it is a rapid technique requiring little sample preparation. Pyrolyzates of samples richer in organic matter (OM) were relatively enriched in aliphatic hydrocarbons and pyrrolic nitrogen compounds, while leaner samples were more aromatic and pyridinic. Alkylbenzene and alkylphenol distributions in the pyrolyzates were most compatible with derivation from aquatic (algal, bacterial) OM. The organonitrogen compounds indicated the presence of degraded proteinaceous material from aquatic sources and/or sewage. Normal and polycyclic aromatic hydrocarbon distributions indicate, at least in …


Development Of An Atmospheric Fluidized Bed Combustor (Afbc), William Orndorff Dec 1997

Development Of An Atmospheric Fluidized Bed Combustor (Afbc), William Orndorff

Masters Theses & Specialist Projects

The relatively recent interest in the U.S. in the development of atmospheric fluidized bed combustion (AFBC) has been preceded by two main factors. First of these is the ever present problem of acid rain and growing public support for cleaner burning fossil fuels. Second is the increasing demand on public landfills and subsequent need for burning of municipal solid waste. From these factors and their corresponding influences, Western Kentucky University has the impetus and has received the financial assistance necessary to build and develop a laboratory scale AFBC system. A brief history of the events leading to this development, as …


A Modeling Study For The Implementation Of In Situ Cometabolic Bioremediation Of Trichloroethylene-Contaminated Groundwater, John A. Christ Dec 1997

A Modeling Study For The Implementation Of In Situ Cometabolic Bioremediation Of Trichloroethylene-Contaminated Groundwater, John A. Christ

Theses and Dissertations

The limitations of conventional groundwater remediation technologies have led to the development of innovative technologies which may achieve national hazardous waste site remediation goals. Before an innovative technology can be implemented in the field, remedial project managers, regulators and other stakeholders require adequate modeling tools to help assess the applicability of the technology at a particular site. This modeling study investigates how an innovative technology, in situ cometabolic bioremediation, might be implemented to remediate a TCE-contaminated site, under different site conditions. A steady-state model is developed which couples an analytical expression to simulate the effect of flow between multiple pumping …


Modeling The Uptake And Transpiration Of Tce Using Phreatophytic Trees, Douglas P. Wise Dec 1997

Modeling The Uptake And Transpiration Of Tce Using Phreatophytic Trees, Douglas P. Wise

Theses and Dissertations

Phytoremediation is a recent addition to the numerous methods used today to remediate ground water contaminants. It is proving more effective and efficient compared to existing remediation techniques. The use of phreatophytes, or water seeking trees, has great potential for phytoremediation. These trees are fast growing, long lived, grow their roots down to the ground water table, transpire large amounts of water, and are proven to actively remove contaminants from the soil horizon. The purpose of this research is to develop quantitative concepts for understanding the dynamics of TCE uptake and transpiration by phreatophytic trees over a short rotation woody …


Evaluation Of Solid Phase Extraction Followed By Supercritical Fluid Elution Of Semi-Volatile Organic Compounds In Toxicity Characteristic Leachates, William Edward Corl Iii Jul 1997

Evaluation Of Solid Phase Extraction Followed By Supercritical Fluid Elution Of Semi-Volatile Organic Compounds In Toxicity Characteristic Leachates, William Edward Corl Iii

Chemistry & Biochemistry Theses & Dissertations

The Environmental Protection Agency (EPA) developed the toxicity characteristic leaching procedure (TCLP) to determine the potential for unknown wastes to leach haz.ardous constituents into the environment. Methods currently being used for the extraction of semi-volatile organic compounds from aqueous TCLP leachates involve acid/base partitioning into methylene chloride. The concentrated extract is then analyzed by gas chromatography/mass spectrometry (GC/MS). The methods are either timeconsuming or labor intensive and they generate significant volumes of haz.ardous wastes themselves. Considering the haz.ards and disposal costs of methylene chloride wastes, great interest has been elicited by the EPA in other extraction techniques which would reduce …


Comparison Of The Dichlorination Of Organic N-Chloramines By Caroate And By Bisulfite: A Kinetic Study, Said H. Lubbad Jul 1997

Comparison Of The Dichlorination Of Organic N-Chloramines By Caroate And By Bisulfite: A Kinetic Study, Said H. Lubbad

Chemistry & Biochemistry Theses & Dissertations

Bisulfite is commonly used to dechlorinate chlorinated municipal wastewater. However, several studies suggest that bisulfite is not effective in dechlorinating N-chlorinated amino components of wastewater. The purpose of this study was to investigate the effectiveness of an alternate dechlorinating agent, caroate (peroxysulfate), and to compare its rate of dechlorination of three different types of chloramines with that of bisulfite.

Four N-chlorinated amino compounds were investigated: N-chlorodiethylamine, chloroalanylphenylalanine, N-chloroglycylphenylalanine, and N-[2-(N'-chloroimino)­ propanoyl]phenylalanine. These compounds were selected from different families of chloramines to study the effect of structure on dechlorination by both caroate and bisulfite. At pH …