关键词: ZSM-5/MCM-41, 乙醇, 乙烯, 脱水

Abstract: Micro/mesoporous ZSM-5/MCM-41 composite molecular sieves were prepared with commercial ZSM-5 zeolite as silica-alumina sources by the treatment of aqueous NaOH solution and with further hydrothermal crystallization using cetyltrimethylammonium bromide（CTMAB）as a structure-directing agent. The influence of various parameters，especially the temperature of the treatment and/or that of the crystallization processes on the crystallization and the morphology of the micro/mesoporous composites has been investigated. The obtained composite materials were further prepared to become catalysts and their catalytic performance on the dehydration of ethanol was carefully illustrated. The results show that micro/mesoporous ZSM-5/MCM-41 composite can be successfully obtained by a two-step method and the optimal condition is that ZSM-5 zeolite was firstly treated at 110 ℃ in a 2.0 mol/L aqueous NaOH solution for 20 h and further crystallized under 110℃ for 20h. H-type catalysts were prepared by ion exchange of the prepared micro/mesoporous ZSM-5/MCM-41 composite with NH4NO3 solution. They show wonderful catalytic performance on the dehydration of ethanol. The conversion of ethanol and the selectivity of ethylene is up to 99% and 96% respectively when the reaction temperature ranges from 240 to 255 ℃ under 0.5 h－1 weight hourly space velocity（WHSV）of ethanol.

Key words: ZSM-5/MCM-41, ethanol, ethylene, dehydration