Download or read book The Effect of Metallic Ions on Trichloroethylene Degradation in Soils written by Earl III. Benjamin and published by . This book was released on 1999 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Enhanced Degradation of Trichloroethylene in the Presence of Metallic Iron and Soil smectites written by Peiliang Shen and published by . This book was released on 1997 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Metals and Nutrients on Trichloroethylene Degradation by Soil Cultures Stimulated by Methane written by Kumar S. Kathinokkula and published by . This book was released on 2002 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Natural Organic Matter Metal Ions and Nitrate on Electrochemical Dechlorination of Trichloroethylene written by Noushin Fallahpour and published by . This book was released on 2016 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: Groundwater is susceptible to pollution due to improper waste disposal. Groundwater contamination continues to be a problem in areas where population relies on groundwater as a major source of drinking water. Development of technologies, such as in situ electrochemical transformation to clean contaminated groundwater is of great importance. Electrochemical systems, which mainly consist of two or more arranged electrodes that are immersed in wells in groundwater, are of interest because of their ability to manipulate redox conditions to transform contaminants into non-toxic forms. Aquifers in karst regions are very susceptible to contamination and present a significant exposure routes due to presence of fissures and channels that facilitate contaminant transport under high flow rate. Trichloroethylene (TCE), a toxic chlorinated solvent that causes major health problems, is present in many contaminated aquifers including many that reside in karst regions. Treatment of aquifers contaminated with TCE is difficult in the presence of other contaminants, such as chromate, selenate, and nitrate, which interfere with TCE transformation and degradation mechanisms. Moreover, presence of natural organic matter (NOM) in the groundwater can influence transformation of TCE and other contaminants. Therefore, it is important to evaluate transformation of TCE in the presence of contaminant mixtures in groundwater. In this study, a series of experiments are conducted to (1) evaluate of the effect of co-existing organic and inorganic compounds on the electrochemical dechlorination of trichloroethylene (TCE) in simulated karst media; and (2) assessment of the impacts of high groundwater flow rates in the presence of palladium (Pd) catalyst on TCE transformation rate and the accumulation of precipitates. A small-scale flow-through limestone column is used to simulate a karst aquifer media to evaluate dechlorination of TCE in the presence of organic and inorganic compounds. Iron anode was used to produce ferrous ions and promote reducing conditions in the column. Various current intensities (30, 60, and 90 mA) were applied under the flow rate of 1 mL min−1 and initial TCE concentration of 1 mg L−1. Under the same testing conditions, presence of chromate has the highest influence on TCE removal followed by selenate and then nitrate. The reduction of TCE under 90 mA current, 1 mL min−1 flow rate, and 1 mg L−1 initial TCE concentration, was inhibited in the presence of humic acids due to competition for direct electron transfer and/or reaction with atomic hydrogen produced at the cathode surface by water electrolysis. The use of iron anode creates favorable conditions for TCE reduction but produces aggregates in combination with ferrous ions, which may impact the long-term performance of the remedial system. A vertical acrylic column, with Pd pellets placed on the cathode surface, was used to investigate the impacts of Pd-based catalysis for the removal of TCE under high flow rate (1 L min−1). The effects of electrode materials and current intensities on precipitation, pH and ORP are assessed. The following electrode materials and arrangements were tested: (a) two MMO electrodes as an anode and a cathode, (b) a cast-iron anode and a MMO cathode, and (c) a cast-iron anode and a copper foam cathode. Current intensities of 500, 250, 125, and 62 mA were tested under the flow rate of 1 L min−1 and 5 mg L−1 of initial concentration of TCE. Under the conditions of 1 L min−1 flow, 500 mA current, and 5 mg L−1 initial concentration of TCE, removal efficacy using iron anodes (96%) is significantly higher than that of mixed metal oxide (MMO) anodes (66%) because the iron anode supports reduction conditions by electrolysis. Two types of cathodes (MMO and copper foam) in the presence of Pd/Al2O3 catalyst under various currents (250, 125, and 62 mA) were used to evaluate the effect of cathode materials on TCE removal efficacy. The similar removal efficiencies were achieved for both cathodes, but more precipitation generated with copper foam cathode. Palladium improved TCE degradation by 120% for 250 mA, 100% for 125 mA, 100% for 62 mA, under the conditions of using an iron anode followed by a copper foam cathode with 1 L min−1 flow rate. The high velocities of groundwater flow can have important implications since the groundwater flow rate can significantly fluctuate, especially in karst aquifers. The optimization of the electrochemical systems for successful operation under high flow rates allows the robustness and great flexibility for the application. It is assumed that the high flow rate would favor the transformation of contaminants since it would flush out precipitates and prevent clogging.
Download or read book The Effects of Trichloroethylene TCE and Toluene on Soil Microbial Community Structure and Function written by Mark Edmund Fuller and published by . This book was released on 1995 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Trichloroethylene Degradation in the Presence of Soil written by Lisa M. Imbrogno and published by . This book was released on 1997 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Index Medicus written by and published by . This book was released on 2003 with total page 1780 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vols. for 1963- include as pt. 2 of the Jan. issue: Medical subject headings.
Download or read book Comparative Plant Uptake and Microbial Degradation of Trichloroethylene in the Rhizospheres of Five Plant Species Implications for Bioremediation of Contaminated Surface Soils written by and published by . This book was released on 1992 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this study was to collect data that would provide a foundation for the concept of using vegetation to enhance in situ bioremediation of contaminated surface soils. Soil and vegetation (Lespedeza cuneata, Paspalum notatum, Pinus taeda, and Solidago sp.) samples from the Miscellaneous Chemicals Basin (MCB) at the Savannah River Site were used in tests to identify critical plant and microbiological variables affecting the fate of trichloroethylene (TCE) in the root zone. Microbiological assays including phospholipid acid analyses, and 14C-acetate incorporation were conducted to elucidate differences in rhizosphere and nonvegetated soil microbial communities from the MCB. The microbial activity, biomass, and degradation of TCE in rhizosphere soils were significantly greater than corresponding nonvegetated soils. Vegetation had a positive effect on microbial degradation of 14C-TCE in whole-plant experiments. Soils from the MCB containing Lespedeza cuneata, Pinus taeda, and Glycine max mineralized greater than 25% of the 14C- TCE added compared with less than 20% in nonvegetated soils. Collectively, these results provide evidence for the positive role of vegetation in enhancing biodegradation.
Download or read book Phytoremediation written by Lee Newman and published by Springer Nature. This book was released on 2023-02-13 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt: The accumulation of large amounts of contaminants occurs in the environment due to industrialization and various other anthropogenic activities. Contaminants ultimately affect human health worldwide. Organic, inorganic, and radioactive substances are the prevalent forms of environmental contaminants and their complete remediation in soils and sediments is rather a difficult task. Concerns of their toxicities led to the emphasis on development of effective techniques to assess the presence and mobility of contaminants in air, water, and soil. Furthermore, the ever-increasing concentration of toxic pollutants in the environment is considered a serious threat to plant, animal, human, and environmental health. Many technologies are in use to clean and eliminate hazardous contaminants from the environment; however, these technologies can be costly, labor intensive, and often distressing to the general public. Phytoremediation is a simple, cost effective, environmentally friendly and fast-emerging new technology for eliminating toxic contaminants from different environments. Phytoremediation refers to the natural ability of certain plants and their associated microbiome (including hyper-accumulators or bio-accumulators) to remove, degrade, or render contaminants harmless. Through this technique, certain species of plants flourish by accumulating contaminants present in the environment. The unique and selective uptake capabilities of plant root and shoot systems, effective translocation, bioaccumulation, and contaminant degradation capabilities of the accumulator plants are utilized in phytoremediation techniques. Phytotechnologies involving the use of plants for contaminant removal gained importance during the last two decades and phytoremediation technology became an effective tool for environmental detoxification because of plants ability to accumulate the contaminants at very high concentrations. Phytoremediation strategies can remove, degrade, or stabilize inorganic and organic contaminants entering a multitude of ecosystems using green plants and their associated microbial communities. The development and use of phytotechnologies continues to move forward at a steady pace. Researchers recognize the potential of phytoremediation to offer a green, cost effective, eco-friendly and feasible application to address some of the world’s many environmental challenges. This book provides significant information to add to the previous volumes published on the topic and can serve as the foundation for the development of new applications that feature the integration of modern research discoveries into new methods to remediate contaminated ecosystems. Moreover, this volume brings recent and established knowledge on different aspects of phytoremediation and nano-phytoremediation, providing this information in a single source that offers a cutting-edge synthesis of scientific and experiential knowledge on polluted environments that is useful for policy makers, practitioners and scientists, and engineers. Phytoremediation: Management of Environmental Contaminants, Volume 7 highlights the various prospects that are involved in current global phytoremediation research. This book delivers a content-rich source to the reader and can act as a platform for further research studies. It should meet the needs of all researchers working in, or have an interest in this particular field.
Download or read book Applied and Environmental Microbiology written by and published by . This book was released on 1994 with total page 818 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aqualine Abstracts written by and published by . This book was released on 1990 with total page 798 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1989 with total page 838 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy Research Abstracts written by and published by . This book was released on 1991 with total page 800 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Inorganic Nanoparticles written by Claudia Altavilla and published by CRC Press. This book was released on 2017-12-19 with total page 601 pages. Available in PDF, EPUB and Kindle. Book excerpt: Among the various nanomaterials, inorganic nanoparticles are extremely important in modern technologies. They can be easily and cheaply synthesized and mass produced, and for this reason, they can also be more readily integrated into applications. Inorganic Nanoparticles: Synthesis, Applications, and Perspectives presents an overview of these special materials and explores the myriad ways in which they are used. It addresses a wide range of topics, including: Application of nanoparticles in magnetic storage media Use of metal and oxide nanoparticles to improve performance of oxide thin films as conducting media in commercial gas and vapor sensors Advances in semiconductors for light-emitting devices and other areas related to the energy sector, such as solar energy and energy storage devices (fuel cells, rechargeable batteries, etc.) The expanding role of nanosized particles in the field of catalysis, art conservation, and biomedicine The book’s contributors address the growing global interest in the application of inorganic nanoparticles in various technological sectors. Discussing advances in materials, device fabrication, and large-scale production—all of which are urgently required to reduce global energy demands—they cover innovations in areas such as solid-state lighting, detailing how it still offers higher efficiency but higher costs, compared to conventional lighting. They also address the impact of nanotechnology in the biomedical field, focusing on topics such as quantum dots for bioimaging, nanoparticle-based cancer therapy, drug delivery, antibacterial agents, and more. Fills the informational gap on the wide range of applications for inorganic nanoparticles in areas including biomedicine, electronics, storage media, conservation of cultural heritage, optics, textiles, and cosmetics Assembling work from an array of experts at the top of their respective fields, this book delivers a useful analysis of the vast scope of existing and potential applications for inorganic nanoparticles. Versatile as either a professional research resource or textbook, this effective tool elucidates fundamentals and current advances associated with design, characterization, and application development of this promising and ever-evolving device.
Download or read book Iron Nanomaterials for Water and Soil Treatment written by Marta I. Litter and published by CRC Press. This book was released on 2018-09-03 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanotechnology has a great potential for providing efficient, cost-effective, and environmentally acceptable solutions to face the increasing requirements on quality and quantity of fresh water for industrial, agricultural, or human use. Iron nanomaterials, either zerovalent iron (nZVI) or iron oxides (nFeOx), present key physicochemical properties that make them particularly attractive as contaminant removal agents for water and soil cleaning. The large surface area of these nanoparticles imparts high sorption capacity to them, along with the ability to be functionalized for the enhancement of their affinity and selectivity. However, one of the most important properties is the outstanding capacity to act as redox-active materials, transforming the pollutants to less noxious chemical species by either oxidation or reduction, such as reduction of Cr(VI) to Cr(III) and dehalogenation of hydrocarbons. This book focuses on the methods of preparation of iron nanomaterials that can carry out contaminant removal processes and the use of these nanoparticles for cleaning waters and soils. It carefully explains the different aspects of the synthesis and characterization of iron nanoparticles and methods to evaluate their ability to remove contaminants, along with practical deployment. It overviews the advantages and disadvantages of using iron-based nanomaterials and presents a vision for the future of this nanotechnology. While this is an easy-to-understand book for beginners, it provides the latest updates to experts of this field. It also opens a multidisciplinary scope for engineers, scientists, and undergraduate and postgraduate students. Although there are a number of books published on the subject of nanomaterials, not too many of them are especially devoted to iron materials, which are rather of low cost, are nontoxic, and can be prepared easily and envisaged to be used in a large variety of applications. The literature has scarce reviews on preparation of iron nanoparticles from natural sources and lacks emphasis on the different processes, such as adsorption, redox pathways, and ionic exchange, taking place in the removal of different pollutants. Reports and mechanisms on soil treatment are not commonly found in the literature. This book opens a multidisciplinary scope for engineers and scientists and also for undergraduate or postgraduate students.
Download or read book Bioavailability of Contaminants in Soils and Sediments written by National Research Council and published by National Academies Press. This book was released on 2003-05-03 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bioavailability refers to the extent to which humans and ecological receptors are exposed to contaminants in soil or sediment. The concept of bioavailability has recently piqued the interest of the hazardous waste industry as an important consideration in deciding how much waste to clean up. The rationale is that if contaminants in soil and sediment are not bioavailable, then more contaminant mass can be left in place without creating additional risk. A new NRC report notes that the potential for the consideration of bioavailability to influence decision-making is greatest where certain chemical, environmental, and regulatory factors align. The current use of bioavailability in risk assessment and hazardous waste cleanup regulations is demystified, and acceptable tools and models for bioavailability assessment are discussed and ranked according to seven criteria. Finally, the intimate link between bioavailability and bioremediation is explored. The report concludes with suggestions for moving bioavailability forward in the regulatory arena for both soil and sediment cleanup.
Download or read book Handbook of Bioremediation written by Mirza Hasanuzzaman and published by Academic Press. This book was released on 2020-10-18 with total page 766 pages. Available in PDF, EPUB and Kindle. Book excerpt: Handbook of Bioremediation: Physiological, Molecular and Biotechnological Interventions discusses the mechanisms of responding to inorganic and organic pollutants in the environment using different approaches of phytoremediation and bioremediation. Part One focuses specifically on inorganic pollutants and the use of techniques such as metallothionein-assisted remediation, phytoextraction and genetic manipulation. Part Two covers organic pollutants and consider topics such as plant enzymes, antioxidant defense systems and the remediation mechanisms of different plant species. This comprehensive volume is a must-read for researchers interested in plant science, agriculture, soil science and environmental science. The techniques covered in this book will ensure scientists have the knowledge to practice effective bioremediation techniques themselves. Provides a comprehensive review of the latest advances in bioremediation of organic and inorganic pollutants Discusses a range of different phytoremediation techniques Evaluates the role of genomics and bioinformatics within bioremediation
