Processing Of Dichloromethane Gas By Catalytic Reduction With Bimetallic Iron Particles

In this paper, bimetallic Ag/Fe,Cu/Fe,Ni/Fe paticles were produced, simulated dichloromethane gas was absorbed and treated by Ag/Fe-H2O, Cu/Fe-H2O and Ni/Fe-H2O systems. Study was focused at the impacts of pH,bimetal ratio,retention time and dosage of iron to the reductive dechlororination between dichloromethane and iron and purification coefficiency of the simulated gas.It is found that the reductive dechlororination is more reactive and purification coefficiency is higher at lower pH.The results shows that the dechlororinating ratios of dichloromethane in the Ag/Fe-H2O system are 6.79%,3.00%,1.27% when pH are 5,7,9.H+may participate in the reductive dechlororination, Fe(OH)2 is more difficult to generate in lower pH and H2 generated by H+may also help the reaction. Bimetallic Ag/Fe,Cu/Fe,Ni/Fe paticles are more effective than normal iron paticles,both the dechlororination rate and the purification coefficiency of dichloromethane increase as the bimetal ratio increases. Bimetallic Ni/Fe is best as Cu/Fe is worst in improving the dechlororination of dichloromethane.Increase the retention time of dichloromethane in the system can raise the purification coefficiency,but the concentration of dichloromethane in the liquid is lower,which makes the dechlororination rate smaller. Dechlororination rate of dichloromethane increases as the dosage of bimetallic Ag/Fe paticles increases, the purification coefficiency increases too.Beside the dechlororination of dichloromethane,adsorption of the dichloromethane by iron may another reason for the purification.