Studies On The Catalytic Hydrodechlorination Of Silicon Tetrachloride And The Catalytic Hydrodechlorination Of Carbon Tetrachloride

In the production process of polysilicon by siemens process,the silicon tetrachloride which treated as byproduct can be made a better use by recycling hydrogenation,which make the conversion of silicon tetrachloride to trichlorosilane.The purity of the product and the energy consumption are major problems,which can be solved through catalytic hydrodechlorination.In the catalytic hydrodechlorination,to maintain the catalytic stability of anti-chlorine-poisoning is the primary factor of catalytic application.This article takes the catalytic hydrodechlorination as the main handhold.The catalytic hydrodechlorination of silicon tetrachloride and carbon tetrachloride have been mainly studied,the catalytic hydrodechlorination of chlorobenzene has also been involved.The study of catalytic hydrodechlorination of silicon tetrachloride include the thermo-catalytic process and the photo-catalytic process.In the thermo-catalytic process,the optimum technological conditions have been found used double metal silicides loaded on the activated carbon.Amoung the double metal silicides loaded on the activated carbon,the effect of alloying elements promote the catalytic hydrodechlorination of silicon tetrachloride especially in Cu-Pd/C.In comparison with Ni-SiC,the appearance of increased and then decreased activity changed as the temperature rising due to the instability of active carbon in high temperature has been discussed.The XRD,BET,TPR analysis of the catalyst have been performed.In the photocatalytic process refered to the reaction of gaseous state silicon tetrachloride and hydrogen,the capability of Pt in Pt/TiO2 to adsorb and activate the hydrogen play a critical role in the photocatalytic hydrodechlorination process.The XRD,BET analysis of the catalyst have been performed.Focusing on the catalytic hydrodechlorination of carbon tetrachloride and chlorobenzene as the probe reaction,the problem of chlorine poisoning in catalytic hydrodechlorination has been studied.The addition of barium chloride into the catalyst as the accessory ingredient can strengthen the bility of anti-chlorine-poisoning that can promote the activity and stability of the catalyst based on the unchanged quantity of Pt loaded on the Al2O3 in catalytic hydrodechlorination of carbon tetrachloride.The optimum appending percentage is 1%(wt%).In the catalytic hydrodechlorination of chlorobenzene,appending the barium chloride can make the catalytic activity to decrease,without the chlorine poisoning,the coke formation is the main reason of the catalyst poisoning.The XRD,BET,TPR,TEM analysis of the catalyst have also been performed.