Modification of Gas-phase Deposition and Coking Resistance over HZSM-5 Catalysts for Toluene Disproportionation
1. School of Petrochemical Engineering, Shenyang University of Technology, Liaoyang 111003, China;
2. Shuangxing Engineering Plastic Branch Company, North Huajin Chemical Industries Group Corporation, Panjin 124000, China
Abstract：To make HZSM-5 catalysts has higher catalytic activity of toluene disproportionation, improve the p-xylene selectivity and stability of coking resistance on HZSM-5 catalysts, Tetrabutyl titanate, ethyl orthosilicate and dietyl phosphite were used for chemical gas-phase deposition modification on HZSM-5 catalysts. The properties of acid sites on catalysts were characterized by infrared spectroscopy (IR) and temperature programmed desorption of pyridine (TPD) respectively. The experimental results showed that the type of acid sites and density of weaker acid sites over HZSM-5 zeolites deposited by oxides containing Ti, Si and P in chemical vapor coating did not change while density of stronger acid sites decreased, in which acid intensity on HZSM-5 zeolite deposited by oxides containing P enhanced obviously. Using HZSM-5 zeolites modified as catalysts of toluene disproportionation, HZSM-5 catalysts deposited by oxides containing Si and P can greatly improve both catalytic activity and coking resistance on catalysts.
Fu Chengbi1,Liu Tao1,Zhu Jing1 et al. Modification of Gas-phase Deposition and Coking Resistance over HZSM-5 Catalysts for Toluene Disproportionation[J]. 化学反应工程与工艺, 2015, 31(1): 21-25.
