HZSM-5结晶度和晶粒度对甲烷无氧芳构化催化剂性能的影响

使用高能球磨机通过研磨法制备了Ｍｏ／ＨＺＳＭ－５催化剂，对不同球磨时间下的催化剂结构进行了表征，并考察了其催化甲烷芳构化性能。结果表明，球磨使ＨＺＳＭ－５分子筛的粒度变小，且使Ｍｏ与骨架发生了同晶置换，导致ＺＳＭ－５骨架破坏；球磨时间越长，结晶度越低，其催化甲烷芳构化活性和苯选择性越差。因此，较高的结晶度和较大的晶粒度对甲烷的无氧芳构化反应更有利。

EFFECTS OF CRYSTALLINITY AND GRAIN SIZE OF HZSM 5 ON AROMATIZATION OF METHANE TO BENZENE

Mo/HZSM 5 catalyst was prepared by grind method using a high energy ball grinder. The Mo/HZSM 5 samples at different grinding time were characterized and their catalytic performance in aromatization of methane to benzene was investigated. It was found that the grain size of HZSM 5 became smaller by grinding and, at the same time, the isomorphous replacement took place between Mo and Al or Si atoms in framework of the zeolite, which resulted in the destruction of HZSM 5 framework. The longer the grinding time is, the smaller the grain size of HZSM 5 is, the lower the crystallinity of HZSM 5 is, and the poorer the activity for methane conversion and benzene selectivity is. Therefore, it is considered that higher crystallinity and larger grain size are favorable for methane aromatization.