Chlorine has been used extensively as an industrial compound for synthesis of innumerable commercial product, including bleaches, organic diluents, adhesives, dust reducing agents, cutting oils, disinfectants, and monomers for plastics, pharmaceuticals, and pesticides. Despite societal contribution of chlorinated chemicals, there have recent suggestion by some environmental associations and scientists to ban the industrial use of chlorine. After their release into environment, organochlorine pollutants are stable and resistant to chemical and biodegradation and preferentially accumulation in the sequence food chain. / As a detoxification hydrodechlorination (HDC) reactions change neither the thermodynamics of the reaction nor the equilibrium composition. Also, there is no possibility of producing hazard by-product such as polychlorodibenzodioxins and polychlorodibenzofuran. / Liquid phase hydrodechlorination of 4-chlorophenols was studied over the temperature range from room temperature (R.T) to 80°C using various Nickel catalysts and active hydrogen sources. Raney Nickel system converted 4-chlorophenol to ~49 mol% of phenol and ~34 mol% cyclohexanol at R.T. and proved to be more reactive than Ni0 and Ni-Fe. The HDC system with borohydrides as hydrogen source achieved hydrodechlorination at lower temperature than the system with molecular hydrogen. Ni-Al proved to be reactive for hydrogenolysis in the presence of borohydride at R.T. A somewhat surprising temperature dependence of Ni-Al mediated HDC in absence of H2 and borohydride was absented. Optimization with Ni-Al under mild condition was performed using central composite design (CCD). Optimal condition for maximum phenol production was predicted to be 80°C, for 11 h with 30 mg of catalyst. 98 mol% phenol is produced under this condition. / A continuous stream of pentachlorophenol (PCP, 0.5 mg/min) in mixture of supercritical carbon dioxide (scCO2) and hydrogen was hydrodechlorinated by a heated column of gamma-alumina supported palladium (5 % w/w). Dechlorination efficiencies and time to reach equilibrium were influenced appreciable by the temperature and substrate delivery rate. The product from reaction at 210°C, 2000 psi accounted for 92 mol% phenol and 2.3 mol% cyclohexanone. The temperature was maintained at 210°C while the pressure and content of H2 in the gas mixture was changed to 1000 ~ 2000 psi, 5 % and 16 % (v/v) H2/CO2. The production of phenol and cyclohexanone was greater at higher pressures (2000 psi.) with the formation of methoxy-cyclohexane. The content of H2 in the gas mixture was not appreciable influenced the product distribution.

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Biological cells and subcellular organelles are surrounded by membranes to form compartments performing specialized functions. Adsorption or partitioning of biologically active compounds into the membrane is the first step in the process of modification of cell function. This work is concerned with the problem of distribution of charged molecules between water and electrically charged membrane surface and between water and octanol. Part I of this thesis is focused on the electrostatic interactions taking place between charges on the membrane and ions present in the aqueous region of the membrane/water interface. The objective was to explore theoretically the origin of anomalous behavior of Ruthenium Red (RuR), a positively charged hexavalent ion. It was discovered in studies of RuR adsorption to negatively charged membranes that within the framework of the Gouy-Chapman theory of the membrane/water interface, RuR behaves as an ion with effective charge less than its physical charge. Moreover, the effective charge was found to be dependent on the density of electric charge at the membrane surface. Two theoretical models of the interfacial region were examined: the Rod Model and the Maximum Density Model. The Rod Model takes into account steric constraints imposed on RuR at the vicinity of the membrane surface. The Maximum Density Model attempts to account for non-ideal behavior by including repulsive interactions. These theoretical studies illustrate the consequences of finite size and ion-ion interactions of adsorption of large molecular ions to electrically charged membrane surfaces. Part II is an experimental study whose objective was to determine the partition coefficient of the negatively charged 2,3,4,5-tetrachlorophenol (TeCP) between water and octanol. The study was based on spectrophotometric measurements of the equilibrium concentrations of TeCP in water and octanol as a function of pH. The octanol/water partition coefficient for both the non-ionized and ionized species of TeCP were determined. It was found that the partition coefficient of ionized TeCP to lipid membrane is about 400 times greater than that for octanol. This result supports the hypothesis that the octanol/water partition coefficient of ionized chlorophenols cannot be used for predicting their distribution between water and lipid-bilayercontaining elements of the environment.