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The Wet Air Oxidation process has considerable attractions for the disposal of toxic organic wastes. In this thesis, a fundamental study is made of the mechanism of oxidation under wet air and related conditions of a series of well-defined substances known to occur as components of industrial wastes, and which are known to present difficulties in the Wet Air Oxidation process. In the initial stages, the oxidation of a series of simple alkylpyridines, namely 2-, 3-, and 4-methylpyridines, has been studied under simulated Wet Air Oxidation plant conditions in a laboratory autoclave operating at 250°C and 250 atmospheres. The progress of the oxidation was followed by withdrawing samples at intervals and subjecting these to chromatographic analysis, using Gas Chromatography-Mass Spectrometry and High Performance Liquid Chromatography, so as to establish the nature of the oxidation products. In the autoclave oxidation of 2-, and 4-methylpyridine, a wide range of oxidation products was detected, including a number of compounds which appeared to be derived from the reactions of pyridylalkyl radicals formed from the parent substance, implying that a free radical mechanism was occurring under Wet Air Oxidation conditions. Under these conditions, 3-methylpyridine appeared to be more resistant to oxidation, the only significant oxidation product being the related aldehyde. The literature suggests that the formation of the hydroxyl radical (OH) under Wet Air Oxidation conditions may be responsible for the initiation of the above reactions, and thus the possibility of catalysis of the above systems by reagents known to generate hydroxyl radicals has been explored. The literature suggests that Fenton's reagent, which is a mixture of iron(ll) and hydrogen peroxide, provides a source of hydroxyl radicals. Thus, the oxidation of the methylpyridines using Fenton's reagent at ambient temperature and atmospheric pressure was carried out and it was also used as a catalyst in the autoclave oxidation reactions. The effectiveness of other metal ion/hydrogen peroxide mixtures was explored, e.g. involving iron(lll), copper(ll), copper(l), titanium(lll), and vanadium(IV), as there is considerable evidence from the literature of their involvement in oxidation chemistry. In all of the oxidation reactions investigated, both under autoclave conditions, and at room temperature, evidence of destructive oxidation of the heteroaromatic ring has been gained for all three methylpyridines. However, in addition to ring destruction products, a range of intermediate oxidation products was observed and similarities were found between those products formed in the autoclave and those reactions carried out in the laboratory. However, recent literature has questioned the formation of hydroxyl radicals by Fenton and related reagents, and so the Fenton catalysed oxidation of each of the methylpyridines was explored further. This was done by the incorporation of appropriate radical trapping agents and complexing agents such as 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) and ethylenediaminetetraacetic acid (EDTA) respectively. In each of the oxidation reactions studied, attempts have been made to identify as many as possible of the products observed by comparison with known substances. However, it has been necessary to develop procedures for the preparation of some of these compounds, notably a range of dimeric structures derived from the simple alkylpyridines, e.g. dipyridylethenes, dipyridylethanes, and dipyridylmethanes.

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The report discusses the destruction of toxic and non-toxic solids, liquids and gases through lasers. In order to completely understand the project first chapters describes the basics about laser and plasma separately, from definition to types, components and categories. Differences between laser and microwave system are covered in this chapter as well. Besides lasers there are different technologies that are currently being used to destroy toxic and non-toxic materials. These technologies were studied and comparison tables are made in order to discern between different destruction technologies. For the destruction of toxic and non-toxic materials through lasers two mathematical models have been developed, molecular dissociation model and plasma exploitation model, and later the experimental work was carried out on one of the toxic material. Mathematical modeling and experimental work is in accordance with each other as discussed in results and discussion. Mathematical model shows that all the materials discussed in the report can be destroyed by lasers but in order to carry further experiments on all other toxic and non-toxic materials, a proposal is made for the laser reactor using CAD model (Solid Edge) and drawing software (AutoCAD). Tables and mathematical calculations have been placed in appendix at the end of the report.

Environmental justice activists defined an environmental justice, or community-led, research practice as an alternative conception of science to guide epidemiological investigations of the human health effects of hazardous wastes. Activists inserted their position into an ongoing scientific controversy where multiple epidemiologies existed--environmental, dumpsite, and popular--reflecting various understandings and interests of federal and academic epidemiologists, state public health officials, and anti-toxics activists. A 1991 national symposium on health research needs and the National Environmental Justice Advisory Council, established in 1993 to advise the Environmental Protection Agency, provided important locations through which activists advocated an environmental justice research approach and pressed for its adoption by relevant governmental public health institutions. The shaping of environmental justice research by activists raises intriguing issues about the role of science and expertise in political protest and the importance of democratic participation in the making of environmental policy. / Ph. D.

The United States Environmental Protection Agency has declared the development of new, portable, and effective detection technology for toxic waste sites a necessity. Current methods are expensive, cumbersome, and often only marginally effective. This project was designed as a first step in a programmatic approach to explore the feasibility of using dogs to locate, delineate, and trace leaching from toxic chemical dump sites. Two Australian Shepherds were trained to detect formaldehyde, a chemical common to many hazardous dumpsites. The training method employed was an adaptation of the military working dog explosives detection protocol. Following training, the dogs were tested to ensure that they could indeed detect 0.5 ml of formaldehyde. Upon confirmation of the dogs’ ability to detect formaldehyde, threshold determinations were implemented. In Experiment I, 0.5 ml of formaldehyde was buried at depths ranging from zero to two feet, in an effort to determine the maximum depth at which the dogs were capable of detecting 0.5 ml of formaldehyde. Results from Experiment I indicate that the dogs were incapable of detecting 0.5 ml of buried formaldehyde, regardless of the depth at which the formaldehyde was buried, despite the fact that the dogs could readily detect 0.5 ml above ground. In Experiment II, field thresholds were determined by burying increasing amounts of formaldehyde (from zero to 10 ml in one ml increments) at a constant depth of one foot. The dogs were able to detect a combined total of 6.50 ml of buried formaldehyde. There was no difference in the dogs’ abilities when compared for ascending, descending, and overall trials. Further, no difference was found between the dogs and their abilities. Results from Experiments I and II indicate that it is indeed feasible to use dogs for the aforementioned purposes. / Master of Science

A generic conflict model is developed to analyze international toxic waste disposal issues, and then, to provide feasible strategic resolutions for this serious environmental dispute. With the rapid growth of the global economy, toxic waste traffic from the advanced to developing nations has become a serious side effect of this globalization. The illegal transboundary movement of toxic wastes not only aggravates the burden on the poorer nations, but also negatively impacts the worldwide environment. In this thesis, the ongoing toxic waste disputes are divided into two stages consisting of the dumping prevention and dispute resolution stages. The analyses based on the methodology of Graph Model for Conflict Resolution are used in both stages in order to grasp the structure and implications of the conflict from a strategic viewpoint. The in-depth modeling of the toxic waste dumping disputes, which consist of historical and generic situations, specifies the involved parties and their options. By synthesizing the economic, political and legal factors, the relative preferences for each party can be determined. The Graphical User Interface (GUI) of the Decision Support System (DSS) GMCR II simplifies the processing of calculations. The analytical research furnishes investigators or other interested parties with possible resolutions for the disputes arising from an international waste dumping event. Sensitivity analyses are also conducted to provide a comprehensive understanding of the different situations that may occur in real-world cases. The case study of the Ivory Coast waste dumping controversy is used to demonstrate how to practically implement the generic multi-stage graph model.

A generic conflict model is developed to analyze international toxic waste disposal issues, and then, to provide feasible strategic resolutions for this serious environmental dispute. With the rapid growth of the global economy, toxic waste traffic from the advanced to developing nations has become a serious side effect of this globalization. The illegal transboundary movement of toxic wastes not only aggravates the burden on the poorer nations, but also negatively impacts the worldwide environment. In this thesis, the ongoing toxic waste disputes are divided into two stages consisting of the dumping prevention and dispute resolution stages. The analyses based on the methodology of Graph Model for Conflict Resolution are used in both stages in order to grasp the structure and implications of the conflict from a strategic viewpoint. The in-depth modeling of the toxic waste dumping disputes, which consist of historical and generic situations, specifies the involved parties and their options. By synthesizing the economic, political and legal factors, the relative preferences for each party can be determined. The Graphical User Interface (GUI) of the Decision Support System (DSS) GMCR II simplifies the processing of calculations. The analytical research furnishes investigators or other interested parties with possible resolutions for the disputes arising from an international waste dumping event. Sensitivity analyses are also conducted to provide a comprehensive understanding of the different situations that may occur in real-world cases. The case study of the Ivory Coast waste dumping controversy is used to demonstrate how to practically implement the generic multi-stage graph model.

Modern Societies have to consider diverse tasks strongly related to geochemistry sciences. Examples intensively discussed in the public are restoration measures for contaminated industrial fallow grounds, the safe storage of chemical-toxic and radioactive waste, carbon dioxide sequestration to reduce green-house gas emissions, the construction and operation of deep geothermal power plants, the geochemical exploration of natural resources or water and waste water treatments, including desalination efforts. Direct and urgent aspects to be dealt with are analytical and geochemical consequences of the Fukushima Daiichi nuclear disaster. All these cases have one in common – they require reliable thermodynamic data in order to forecast the fate of chemicals in the respective environment. Whereas a variety of standard methods, such as potentiometry, solubility studies, liquid-liquid extraction or electrochemical titrations, are in widespread use to generate thermodynamic data, it is far less straightforward to assign correct reaction pathways and structural patterns to the underlying chemical transformations. This especially holds for systems with strong tendencies to complexation and oligomerization. Here, it is essential to have proof of evidence for all involved species, which cannot be provided by the aforementioned methods, and is still lacking for various metal-containing systems. Spectroscopic techniques in combination with approaches from quantum chemistry can be of great benefit for such tasks. However, their application ranges are often restricted with respect to the type of element (and redox state) that can be probed. Further handicaps are imposed by detection limits or other parameters such as pH or salinity. Moreover, the spectroscopic results are often difficult to interpret in an unambiguous way. To overcome these complications at least partially, this workshop has been initiated. It shall significantly extend the application areas of spectroscopic tools important for lanthanide and actinide chemistry. Emphasis shall be placed on the development of spectroscopic methods towards more challenging environmental conditions – such as very basic pH values, elevated temperatures, pressures, or salinities – extending the range of covered elements and redox states. Furthermore, the exploration of options for lowering detection limits and increasing spatial resolution at sufficiently high signal-to-noise ratios will support future investigations on more complex systems. An approach combining the extension of spectroscopic tools with respect to elements and parameters, improvements of experimental setups, and applications of quantum chemical methods in predictive as well as interpretative ways certainly can be very beneficial. The workshop hopefully will bundle and strengthen respective research activities and ideally act as a nucleus for an international network, closely collaborating with international partners. I am confident that the workshop will deliver many exciting ideas, promote scientific discussions, stimulate new developments and in such a way be successful.

Modern Societies have to consider diverse tasks strongly related to geochemistry sciences. Examples intensively discussed in the public are restoration measures for contaminated industrial fallow grounds, the safe storage of chemical-toxic and radioactive waste, carbon dioxide sequestration to reduce green-house gas emissions, the construction and operation of deep geothermal power plants, the geochemical exploration of natural resources or water and waste water treatments, including desalination efforts. Direct and urgent aspects to be dealt with are analytical and geochemical consequences of the Fukushima Daiichi nuclear disaster. All these cases have one in common – they require reliable thermodynamic data in order to forecast the fate of chemicals in the respective environment. Whereas a variety of standard methods, such as potentiometry, solubility studies, liquid-liquid extraction or electrochemical titrations, are in widespread use to generate thermodynamic data, it is far less straightforward to assign correct reaction pathways and structural patterns to the underlying chemical transformations. This especially holds for systems with strong tendencies to complexation and oligomerization. Here, it is essential to have proof of evidence for all involved species, which cannot be provided by the aforementioned methods, and is still lacking for various metal-containing systems. Spectroscopic techniques in combination with approaches from quantum chemistry can be of great benefit for such tasks. However, their application ranges are often restricted with respect to the type of element (and redox state) that can be probed. Further handicaps are imposed by detection limits or other parameters such as pH or salinity. Moreover, the spectroscopic results are often difficult to interpret in an unambiguous way. To overcome these complications at least partially, this workshop has been initiated. It shall significantly extend the application areas of spectroscopic tools important for lanthanide and actinide chemistry. Emphasis shall be placed on the development of spectroscopic methods towards more challenging environmental conditions – such as very basic pH values, elevated temperatures, pressures, or salinities – extending the range of covered elements and redox states. Furthermore, the exploration of options for lowering detection limits and increasing spatial resolution at sufficiently high signal-to-noise ratios will support future investigations on more complex systems. An approach combining the extension of spectroscopic tools with respect to elements and parameters, improvements of experimental setups, and applications of quantum chemical methods in predictive as well as interpretative ways certainly can be very beneficial. The workshop hopefully will bundle and strengthen respective research activities and ideally act as a nucleus for an international network, closely collaborating with international partners. I am confident that the workshop will deliver many exciting ideas, promote scientific discussions, stimulate new developments and in such a way be successful.