Download or read book The Reductive Dechlorination of Tetrachloroethylene Trichloroethylene and Carbon Tetrachloride Mixtures by Anaerobic Bacteria written by Rebecca Davis and published by . This book was released on 1999 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Kinetics of Reductive Dechlorination of Trichloroethane TCA by Anaerobic Biofilms written by Rittmann Bruce E. and published by . This book was released on 1995 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sequential Transformation of Carbon Tetrachloride Perchloroethylene and 1 1 1 Trichloroethane Using Methanogenic and Methanotrophic Conditions written by Sarah Jane Christ and published by . This book was released on 1996 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: A methanogenic-methanotrophic system has been established to assess the capability of sequential treatment to transform the chlorinated aliphatics perchloroethylene (PCE), carbon tetrachloride (CT) and 1,1,1-trichloroethane (1, 1,1-TCA). Experiments compared the transformation of PCE alone and in a mixture of the target compounds. A comparison of acetate and iron as electron donors was also made. Data from the anaerobic systems have shown that PCE transformation is inhibited when in a mixture with CT and 1,1,1-TCA compared to when it is fed alone. When iron is the electron donor, PCE and 1,1,1-TCA are transformed without an acclimation period. CT was completely transformed regardless of the electron donor used. The acetate-fed system required approximately 60 days to acclimate to 1,1,1-TCA and 70 days for acclimation to PCE. Although the sequential system has been constructed, sampling from the aerobic column was not done before the thesis project ended. More investigation is required to determine the ability of the sequential system to degrade PCE, CT, and 1,1,1- TCA.
Download or read book Factors Affecting the Reductive Dechlorination of Carbon Tetrachloride by Zero valent Iron written by Amanda S. Mutziger and published by . This book was released on 1996 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reductive Dechlorination of Carbon Tetrachloride by Ferrous Sulfide Under Anaerobic Conditions written by Kun-Yu Lin and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reductive Dechlorination of Tetrachloroethene in Polluted Aquifer Microcosms and Isolation of Anaerobic Bacteria from a Tetrachloroethene dechlorinating Enrichment written by Christopher D. Carlson and published by . This book was released on 1997 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reductive Dechlorination of Chlorinated Pollutants by Metals and Organometallics written by Nada Assaf-Anid and published by . This book was released on 1993 with total page 594 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Abiotic Reductive Dechlorination of Tetrachloroethylene and Trichloroethylene in Anaerobic Environments written by and published by . This book was released on 2009 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tetrachloroethylene (PCE) and trichloroethylene (TCE) are among the most frequently detected ground water contaminants at industrial sites, including many DoD facilities. Due to the high cost and uneven performance of traditional remediation technologies, monitored natural attenuation is emerging as a new technology for ground water remediation of pollutants such as these. In addition, there is growing interest in active remediation technologies that employ abiotic minerals. PCE and TCE are susceptible to reductive dechlorination by microorganisms as well as reduced minerals such as iron sulfide (FeS). Unlike biological reductive dechlorination, which often results in accumulation of harmful intermediates such as cis 1,2-dichloroethylene (cis-DCE) and vinyl chloride (VC), abiotic mineral-mediated dechlorination of PCE and TCE tends to result in complete transformation to non-toxic products such as acetylene. To more accurately apply natural attenuation and other remediation technologies, a greater understanding of the geochemical factors affecting the rates of purely abiotic reductive dechlorination of PCE and TCE is needed. Additional tools are also needed to determine whether or not abiotic reductive dechlorination is occurring at a particular site, and its relative importance compared to microbial dechlorination under a variety of geochemical conditions.
Download or read book Synergistic Reductive Dechlorination of 1 1 1 trichloroethane and Trichloroethene and Aerobic Degradation of 1 4 dioxane written by Yihao Luo and published by . This book was released on 2018 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Widespread use of chlorinated solvents for commercial and industrial purposes makes co-occurring contamination by 1,1,1-trichloroethane (TCA), trichloroethene (TCE), and 1,4-dioxane (1,4-D) a serious problem for groundwater. TCE and TCA often are treated by reductive dechlorination, while 1,4-D resists reductive treatment. Aerobic bacteria are able to oxidize 1,4-D, but the biological oxidation of 1,4-D could be inhibited by TCA, TCE, and their reductive transformation products. To overcome the challenges from co-occurring contamination, I propose a two-stage synergistic system. First, anaerobic reduction of the chlorinated hydrocarbons takes place in a H2-based hollow-fiber "X-film" (biofilm or catalyst-coated film) reactor (MXfR), where "X-film" can be a "bio-film0" (MBfR) or an abiotic "palladium-film" (MPfR). Then, aerobic removal of 1,4-D and other organic compounds takes place in an O2-based MBfR. For the reductive part, I tested reductive bio-dechlorination of TCA and TCE simultaneously in an MBfR. I found that the community of anaerobic bacteria can rapidly reduce TCE to cis-dichloroethene (cis-DCE), but further reductions of cis-DCE to vinyl chloride (VC) and VC to ethene were inhibited by TCA. Also, it took months to grow a strong biofilm that could reduce TCA and TCE. Another problem with reductive dechlorination in the MBfR is that mono-chloroethane (MCA) was not reduced to ethane. In contrast, a film of palladium nano-particles (PdNPs), i.e., an MPfR, could the simultaneous reductions of TCA and TCE to mainly ethane, with only small amounts of intermediates: 1,1-dichloroethane (DCA) (~3% of total influent TCA and TCE) and MCA (~1%) in continuous operation. For aerobic oxidation, I enriched an ethanotrophic culture that could oxidize 1,4-D with ethane as the primary electron donor. An O2-based MBfR, inoculated with the enriched ethanotrophic culture, achieved over 99% 1,4-D removal with ethane as the primary electron donor in continuous operation. Finally, I evaluated two-stage treatment with a H2-based MPfR followed by an O2-MBfR. The two-stage system gave complete removal of TCA, TCE, and 1,4-D in continuous operation.
Download or read book Organohalide Respiring Bacteria written by Lorenz Adrian and published by Springer. This book was released on 2016-08-03 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes the current state of knowledge concerning bacteria that use halogenated organic compounds as respiratory electron acceptors. The discovery of organohalide-respiring bacteria has expanded the range of electron acceptors used for energy conservation, and serves as a prime example of how scientific discoveries are enabling innovative engineering solutions that have transformed remediation practice. Individual chapters provide in-depth background information on the discovery, isolation, phylogeny, biochemistry, genomic features, and ecology of individual organohalide-respiring genera, including Dehalococcoides, Dehalogenimonas, Dehalobacter, Desulfitobacterium and Sulfurospirillum, as well as organohalide-respiring members of the Deltaproteobacteria. The book introduces readers to the fascinating biology of organohalide-respiring bacteria, offering a valuable resource for students, engineers and practitioners alike.
Download or read book Dehalogenation written by Max M. Häggblom and published by Springer Science & Business Media. This book was released on 2007-05-08 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt: Halogenated organic compounds constitute one of the largest groups of environmental chemicals. The industrial production of new halogenated organic compounds has increased throughout the last century peaking in the 1960s, and continuing in widespread use today. Organohalides are integral to a variety of industrial applications, including use as solvents, degreasing agents, biocides, pharmaceuticals, plasticizers, hydraulic and heat transfer fluids, and intermediates for chemical synthesis, to name a few. It is important to recognize the beneficial aspects of halogenated organic compounds, as well as their potentially deleterious impact on the environment and health. Recognition ofthe adverse environmental effects ofmanytypes oforganohalide compounds has led to efforts to reduce or eliminate the most problematic ones. Although organohalide compounds are typically considered to be anthropogenic industrial compounds, they have their counterpart in several thousands of natural biogenic and geogenic organohalides, representing most classes of organic chemicals. Natural sources account for a significant portion of the global organohalogen budget. This volume authored by recognized experts in the field provides a current perspective on how both natural and synthetic organohalides are formed and degraded, and how these processes are incorporated into a global halogen cycle. The focus is on microbial processes, since these play a major role both in the production and degradation, i. e. , cycling of halogenated organic compounds inthe environment. This book is organized into five parts. Part I, Introduction, provides a global perspective on the issues of organohalides and their fate in the environment.
Download or read book Bioaugmentation for Groundwater Remediation written by Hans F. Stroo and published by Springer Science & Business Media. This book was released on 2012-10-02 with total page 421 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume provides a review of the past 10 to 15 years of intensive research, development and demonstrations that have been on the forefront of developing bioaugmentation into a viable remedial technology. This volume provides both a primer on the basic microbial processes involved in bioaugmentation, as well as a thorough summary of the methodology for implementing the technology. This reference volume will serve as a valuable resource for environmental remediation professionals who seek to understand, evaluate, and implement bioaugmentation.
Download or read book Applied and Environmental Microbiology written by and published by . This book was released on 1992 with total page 1168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook for cleaning decontamination of surfaces written by Ingegard Johansson and published by Elsevier. This book was released on 2007-06-20 with total page 994 pages. Available in PDF, EPUB and Kindle. Book excerpt: The focus of Handbook for Cleaning/Decontamination of Surfaces lies on cleaning and decontamination of surfaces and solid matter, hard as well as soft. Bringing together in a 2-volume reference source: - current knowledge of the physico-chemical fundamentals underlying the cleaning process; - the different needs for cleaning and how these needs are met by various types of cleaning processes and cleaning agents, including novel approaches; - how to test that cleaning has taken place and to what extent; - the effects of cleaning on the environment; - future trends in cleaning and decontamination, for example the idea of changing surfaces, to hinder the absorbance of dirt and thus make cleaning easier.A brief introduction is given to the legal demands concerning the environment and a historical background, in terms of development of detergents, from soaps to the modern sophisticated formulations. Bactericides, their use and the environmental demands on them are covered. Thorough discussions of mechanisms for cleaning are given in several chapters, both general basic concepts and special cases like particle cleaning and cleaning using microemulsion concepts.* General understanding of how cleaning works, function of ingredients and formulations * Overview of environmental issues and demands from the society in the area * Gives basic formulas for cleaning preparations in most areas
Download or read book In Situ Remediation of Chlorinated Solvent Plumes written by Hans F. Stroo and published by Springer Science & Business Media. This book was released on 2010-09-10 with total page 807 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the late 1970s and early 1980s, our nation began to grapple with the legacy of past disposal practices for toxic chemicals. With the passage in 1980 of the Comprehensive Envir- mental Response, Compensation, and Liability Act (CERCLA), commonly known as Sup- fund, it became the law of the land to remediate these sites. The U. S. Department of Defense (DoD), the nation’s largest industrial organization, also recognized that it too had a legacy of contaminated sites. Historic operations at Army, Navy, Air Force, and Marine Corps facilities, ranges, manufacturing sites, shipyards, and depots had resulted in widespread contamination of soil, groundwater, and sediment. While Superfund began in 1980 to focus on remediation of heavily contaminated sites largely abandoned or neglected by the private sector, the DoD had already initiated its Installation Restoration Program in the mid-1970s. In 1984, the DoD began the Defense Environmental Restoration Program (DERP) for contaminated site assessment and remediation. Two years later, the U. S. Congress codified the DERP and directed the Secretary of Defense to carry out a concurrent program of research, development, and demonstration of innovative remediation technologies. As chronicled in the 1994 National Research Council report, “Ranking Hazardous-Waste Sites for Remedial Action,” our early estimates on the cost and suitability of existing techn- ogies for cleaning up contaminated sites were wildly optimistic. Original estimates, in 1980, projected an average Superfund cleanup cost of a mere $3.
Download or read book Toxicological Profile for Trichloroethylene written by and published by . This book was released on 1997 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Solvent Microextraction written by John M Kokosa and published by John Wiley & Sons. This book was released on 2009-10-05 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers both a practical as well a theoretical approach to Solvent Microextraction (SME) and will help analytical chemists to evaluate SME for a given sample preparation. Introductory chapters overview a comparison of SME with other sample preparation methods, a summary of the technical aspects, and a detailed theoretical treatment of SME. The book then describes the practical aspects of the technique, with detailed “how to” chapters devoted to the preparation and analysis of atmospheric, solid and liquid environmental, clinical and industrial samples. This text will serve as both a handy laboratory desk-reference and an indispensible instructional tool.
