Cu/SiO2催化剂在醋酸甲酯加氢制乙醇反应中失活比较

采用固定床微型反应器考察Cu/ZnO和Cu/SiO₂催化剂在醋酸甲酯加氢制乙醇反应中的稳定性,分别反应1 000 h和750 h后，Cu/ZnO和Cu/SiO2催化剂均失活。采用物理吸附、DTG、原位XRD和H₂-TPR等对失活前后Cu/ZnO和Cu/SiO₂催化剂进行比较。结果表明，Cu/ZnO和Cu/SiO₂催化剂在醋酸甲酯加氢制乙醇反应中失活机理不同，Cu/ZnO 催化剂失活的主要原因是Cu晶粒长大，催化剂上ZnO晶粒同时长大；Cu/SiO₂催化剂失活主要原因是积炭物种对催化剂孔道的堵塞和对活性位的覆盖。

Deactivation comparison of Cu/ZnO and Cu/SiO2 catalysts for methyl acetate hydrogenation to ethanol

The stability of Cu/ZnO catalyst and Cu/SiO2 catalyst for methyl acetate hydrogenation to etha-nol were evaluated in a fixed-bed microreactor. Both catalysts were deactivated after 1 000 h and 750 h running in stream,respectively. Cu/ZnO catalyst and Cu/SiO2 catalyst before and after deactivation were characterized by means of physical absorption,DTG,XRD and H2-TPR techniques. The results showed that deactivation mechanisms of Cu/ZnO and Cu/SiO2 catalysts for methyl acetate hydrogenation to etha-nol were different. The main reason for catalyst deactivation was the simultaneous increase of Cu and ZnO particle sizes on Cu/ZnO catalyst. Whereas,carbon deposition on Cu/SiO2 catalyst was the main reason for its deactivation,which blocked the pores and covered the active sites of the catalyst.