ZnO对CuO-ZnO/Al2O3催化剂催化甘油氢解性能的影响

The effect of ZnO on hydrogenolysis performance for glycerol of CuO-ZnO/ Al2O3 catalyst

摘要:

以氧化铝为载体，采用浸渍法制备了负载型CuO-ZnO/Al2O3催化剂，通过XRD、XPS、TPR手段表征催化剂上CuO和ZnO的分布和化学形态。结果表明：CuO-ZnO/Al2O3催化剂催化甘油氢解反应中，CuO是活性组分，ZnO的引入可以降低CuO与载体氧化铝的相互作用强度，有利于CuO的还原，提高催化剂甘油氢解活性；催化剂表面呈却电子状态的Cu物种是甘油氢解的活性中心。当活性组分CuO含量为12%，Cu/Zn摩尔比为1:1.5时，CuO-ZnO/Al2O3催化剂催化甘油氢解活性最高，甘油转化率可达97.82%，对1，2-丙二醇选择性达94%。

Abstract:

CuO-ZnO/Al2O3 catalysts supported on alumina was prepared by impregnation. XRD, XPS and TPR methods were used to characterize the distribution and chemical forms of CuO and ZnO impregnated on the catalyst. The results showed that copper oxide was the main active component, zinc oxide acted as a promoter in CuO-ZnO/Al2O3 catalysts. ZnO could modify the interaction between copper oxide and the supporter to reduce the reduction temperature of copper oxide. Hence, the hydrogenolysis performance for glycerol of the catalysts was improved. The Cu species in defect of electron was the hydrogenolysis active sites for the hydrogenolysis of glycerol. With a weight loading of 12% of CuO and Cu/Zn molar ratio of 1:1.5 in the catalystst. The conversion of glycerol was up to 97.82%, whereas the selectivity for 1,2-propanediol was nearly to 94%.