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The decompositions of dichloromethane, chloroform tetrachloride, dichloroethylene, chloridetrichloroethylene, and tetrachloroethylene on Cr2O3/γ-Al2O3 catalyst were investigated. The major interests of this research were placed on knowing the conversion and the product distribution of the decomposition. The effects of water and a second organics in the feed were investigated. The cause of catalyst deactivation was also examined. Catalysts were prepared by incipient wetness impregnation and were characterized by ESCA and AA. The decomposition reaction was conducted under atmospheric pressure with a continuous flow tubular reactor. The feeding air contained 1000 ppm organics. The reaction temperatures were ranged from 100℃to 500℃. Under the same reaction condition, the conversions of one -carbon organics decreased in the following order : CCl4>CHCl3>CH2Cl2. The order showed the conversion was proportional to the number of chlorine atom in the compound. For organics of 2-carbons, the order was C2H2Cl2> C2HCl3>C2Cl4. The conversion was decreased with the increase in the number of chlorine atom CO2, HCl, and Cl2 were the major products form the decomposition. The distribution of the products was strongly affected by the reaction temperature and the type of reactants to be decomposed Even though the conversion of CHCl3 was not effected , the product distribution was greatly influenced by the presence of water . The water significantly inhibited the formation of Cl2. In decomposing CH2Cl2, CHCl3, and CCl4, the rate of Cr2O3/γ-Al2O3 catalyst deactivaton was in the order : CCl4>CHCl3>CH2Cl2. The loss of Cr2O3 from Cr2O3/γ-Al2O3 was the main cause of catalyst deactivation.
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