[Catalytic reduction of CCl4 in water by Fe0 and amended Fe0].

Various bimetallic reductants of Cu/Fe, Ag/Fe, Pd/Fe and Ni/Fe were prepared by plating Cu, Ag, Pd and Ni on the surface of Fe0. Reductive dechlorination of toxic pollutants of CCl4 in water with Fe0 and amended Fe0 by batch experiments was investigated. Results show that CCl4 in water can be rapidly dechlorinated by above five catalytic reductants, and the presence of Cu, Ag, Pd can enhance the dechlorination rate dramatically. The reaction of CCl4 with various reductants was followed the pseudo first order kinetics, and the dechlorination rate constant of CCl4 in water by Fe0, Cu/Fe, Ag/Fe, Pd/Fe and Ni/Fe was 0.0393, 0.0925, 0.158, 0.0496 and 0.0533 min(-1) respectively. The byproducts and pathway of dechlorination of CCl4 by Fe0 and amended Fe0 was identified by GC/MS. Results indicate that the products and dechlorination rate of CCl4 by various bimetallic reductants are varied. The main products are chloroform and dichloromethane in Cu/Fe and Ag/Fe system, and that is methane in Pd/Fe system. Hydrogenolysis is the dominant reaction pathway of CCl4 by Fe0 and amended Fe0.