Abstract: 4A zeolite/TiO2 composite catalysts modified with Ce，Mn and Pt were prepared through impregnation and liquid phase deposition. The prepared catalysts were characterized by SEM，XRD and ICP，and their catalytic performances were evaluated with a self-made fixed bed reactor. Results showed that the catalytic performance of 4A zeolite/TiO2 composite catalyst is evidently enhanced compared with that of 4A zeolite，and the ethylene production is further improved when the composite catalyst is modified with Pt. The composite catalyst modification with Ce and Mn exhibits better catalytic performance than either the one modified with Ce or Mn. The enhanced catalytic performance might be attributed to the increased oxygen vacancies in the composite catalysts by the acceptance of thermal-induced electrons with the supported TiO2 from 4A zeolite.

摘要： 采用浸渍和液相沉积联合的方法制备了铈锰铂改性的4A分子筛/TiO2复合催化剂。利用SEM、XRD和ICP表征催化剂的物化性能，并在自制的催化剂评价装置上测试其对于乙醇脱水制取乙烯的催化性能。结果显示，4A分子筛/TiO2复合催化剂的催化性能与4A分子筛相比显著提高，铂改性的复合催化剂能进一步促进乙烯产生，铈-锰改性的复合催化剂比铈或锰单独改性的复合催化剂效果更好。复合催化剂中TiO2可能是通过吸收4A分子筛上受热激发产生的电子，增加复合催化剂上的氧空穴进而促进乙烯的生成。