HZSM-5、HMCM-22和HBeta上苯和甲醇烷基化性能比较

Comparison of Benzene and Methanol Alkylation Performance on HZSM-5、HMCM-22 and HBeta Zeolites

本文对HZSM-5、HMCM-22和HBeta沸石进行了系统表征,采用固定床评价三种沸石样品在苯和甲醇烷基化的反应性能。结果表明,HBeta的十二元环孔道有利于大分子产物的生成,积碳速率快导致催化剂失活最快,而HZSM-5和HMCM-22由于十元环孔道和窗口相对较小,大分子产物不容易生成,积碳速率缓慢,具有较好的稳定性。由于H-MCM-22具有更高的甲苯和二甲苯总选择性,同时乙苯在碳八组分中的百分含量只有1.02%。所以,H-MCM-22催化剂是优异的苯和甲醇烷基化催化剂。

In this paper,the HZSM-5、HMCM-22 and HBeta zeolites were systematically characterized.The reaction performance of the three zeolites in alkylation of benzene and methanol was evaluated in a small fixed-bed reactor.The results show that the 12R channels of H-Beta are favorable for the formation of macromolecular products,which causes the carbon deposition rate to increase and the deactivation of H-Beta to fast.HZSM-5 and HMCM-22 have smaller 10R channels and windows,which restricts the formation of macromolecular transitional species and products.Therefore HZSM-5 and HMCM-22 have a slowly rate of carbon deposition and show a better stability.However,HMCM-22 has higher total selectivity of toluene and xylene,the percentage of ethylbenzene in C8 is only 1.02%.In conclusion,HMCM-22 is an excellent catalyst for alkylation of benzene and methanol.