沸石表面酸性与催化活性的研究

Research on Surface Acidity and the Catalytic Activity of Some Zeolites

采用正丁胺回滴法和乙醇钠溶液电导滴定法测定在不同的灼烧温度下几种分子筛的表面酸度。以乙醇脱水制乙烯为指示反应,在微型管式反应器测定其活性。结果表明,随着灼烧温度升高,分子筛的表面酸度先是增大,而后下降。分别在400～500℃间出现极大值。酸度与活性两者存在对应关系。B酸量对催化活性有直接影响。

In this paper, some works on the relationship between the surface acidity and the catalytic activity of some kinds of zeolites, are reported. Each of them was thermally treated at different temperatures The surface acidity of the zeolites thus treated was determined by backtitration with n-bulylamine as titrant and by conductometric titration using ethanol solution of sodium hydroxide. The catalytic activity of the zeolites was estimated by its ability for the dehydration of ethanol in a tube-reactor. It has teen shown that the catalytic activity and the surface acidity of the zeolites increases with increasing calcination temperature at the beginning, and then decreased through the maximum at the temperature range of 400～500℃. It is apparent that the surface acidity of the zeolites effects greatly their catalytic activity.