ZSM-5分子筛催化剂酸性对积炭的影响

THE EFFECT OF ZSM-5 ZEOLITE ACIDITY ON COKE DEPOSITION

研究了几种分子筛在乙基化反应中的积炭过程,并与分子筛的酸性、孔结构等参数关联,阐明了ZSM-5分子筛催化剂的酸中心对积炭起着主要作用。酸强度越高,越容易积炭,酸量越大积炭越多。积炭的形成部位与酸中心在晶内外的分布关系密切。分子筛外表面酸中心比晶内的更易生成积炭,体现了积炭的择形性。

Coke deposition on several ZSM-5 zeolites in toluene alkylation has been studied and compared with thier acidity and pore structure. It is shown that the acid sites of the zeolites play an important role on coke deposition. The stronger the acid sites are the easier coke deposition will be and more acid sites means more coking locations. Coke deposition on the external surface acid sites is much easier than that in the internal acid sites.