乙烯气相法制醋酸乙烯Pd-Au催化剂研究进展OACSTPCD

Vinyl acetate(VAc)is an important chemical raw material with well application value.With the rapid development of the photovoltaic industry and the improvement of environmental protection requirements,the demand for high-quality vinyl acetate(i.e.,ethylene gas phase process vinyl acetate)in China is increasing year by year.It is of great significance to develop the catalyst with high catalytic activity,high target product selectivity,high stability and low cost.Firstly,the development of catalysts for producing ethylene acetate by ethylene gas phase process was reviewed.The functions of catalyst supports,active components and potassium acetate additive were summarized.The two reaction mechanisms of producing vinyl acetate by ethylene gas phase process and the deactivation causes of Pd-Au catalyst were analyzed.The preparation process of eggshell Pd-Au catalyst by impregnation method was described.Then the research results of catalyst improvement for the purpose of further improving catalytic performance and reducing catalyst cost were summarized,including modification and deformalization of supports,and improvement of procedures,such as impregnation of active components,aging,reduction,washing and drying.Lastly,the research direction of catalyst for producing vinyl acetate by ethylene gas phase process in the future was proposed.