Abstract: HMCM-22/MCM-41 composite molecular sieves with mesoporous and microporous structure were prepared under hydrothermal conditions from HMCM-22. Physicochemical properties of the as-synthesized catalysts were characterized by XRD，N2 adsorption-desorption and NH3-TPD. Results showed the existence of well-structured microphase MCM-22 zeolite and mesophase MCM-41 in the composite materials. Selective alkylation of toluene with dimethyl carbonate (DMC) was carried out over HMCM-22/MCM-41 composite molecular sieves in a fixed-bed flow reactor. Effects of reaction conditions on the alkylation of toluene with DMC were investigated. The selectivity to p-xylene was higher than m- and o-isomers over HMCM-22/MCM-41 which exhibited good catalytic activity and selectivity.

摘要： 以自制的HMCM-22作为原料，与中孔分子筛MCM-41的凝胶在水热条件下进行组装得到HMCM-22/MCM-41中微孔复合分子筛，采用XRD、N2吸附-脱附及NH3-TPD等方法对合成样品进行表征。结果表明，合成的样品同时具有中孔分子筛MCM-41与微孔分子筛HMCM-22的特点。采用固定床微型连续流反应器对HMCM-22/MCM-41复合分子筛催化甲苯与碳酸二甲酯（DMC）的烷基化反应性能进行了评价，考察了反应温度、甲苯与DMC摩尔配比及空速对烷基化反应的影响。实验发现，HMCM-22/MCM-41催化甲苯DMC烷基化反应的产物中，对二甲苯的选择性远高于间位和邻位异构体的选择性，表现出良好的催化活性和选择性。