SAPO-34催化剂上C4烯烃催化裂解与甲醇转化制烯烃反应耦合

摘要

采用SAPO-34催化剂,在流化床装置上考察了甲醇制烯烃(MTO)副产C4烯烃催化裂解制乙烯和丙烯的反应行为,分析了C4烯烃转化率、产物收率等主要指标随工艺参数的变化规律,对比了C4烯烃催化裂解和MTO反应积炭催化剂的差异,提出了C4烯烃催化裂解适宜的关键工艺条件.C4烯烃催化裂解对比MTO反应需要较高的反应温度和催化剂活性.结果表明,C4烯烃裂解反应过程形成的积炭催化剂仍可用于MTO反应,并且具有较高的甲醇转化率和低碳烯烃选择性,因此可以采用SAPO-34催化剂把两个独立的反应串联耦合在一起.%The reaction behavior of catalytic cracking of C4 alkene byproducts from methanol to olefins (MTO) process for ethylene and propylene on SAPO-34 catalyst were investigated in a fluidized bed reactor.The effects of operating conditions such as reaction time,reaction temperature and residence time on C4 alkene conversion and main product yields were studied.Different catalytic performance of catalysts deposited with coke from alkene cracking and MTO process respectively was compared.A suitable operating condition for C4 alkene cracking was then obtained.The results showed that higher reaction temperature and better catalyst with high catalytic activity were required for C4 alkene cracking in comparison with MTO process.The catalyst deposited with coke from alkene cracking could still be used for the MTO reaction with the preservation of high methanol conversion and good selectivity of the light olefins.Therefore,the coupling between C4 alkene cracking and MTO process on the SAPO-34 catalyst could be realized.