Co/Mn/Zr复合催化剂催化甲苯液相氧化

以乙酰丙酮锆或乙酸锆与乙酸钴和乙酸锰制备乙酸钴/乙酸锰/乙酰丙酮锆或乙酸锆(Co/Mn/Zr)三元复合催化剂。比较乙酸钴(Co)、乙酸钴/乙酸锰(Co/Mn)和Co/Mn/Zr催化剂体系对甲苯液相氧化反应的催化性能。结果表明:在催化剂中添加Zr可以降低反应温度,提高甲苯转化率和苯甲酸选择性。与乙酸锆相比,采用乙酰丙酮锆制得的Co/Mn/Zr具有较好的催化活性。在Co,Mn和Zr物质的量之比为5 5 1,Co与甲苯的物质的量之比为1 10 000,溶剂乙酸与甲苯质量比为1 2.3,反应温度160℃和反应压力1.4 MPa的条件下反应3 h后,苯甲酸选择性和甲苯转化率分别为80.2%和15.4%。

Liquid Phase Oxidation of Toluene Catalyzed by Co/Mn/Zr Composite Catalyst

Co/Mn/Zr composite catalyst was prepared using cobalt acetate,manganese acetate,zirconium acetate or zirconium(IV) acetylacetonate(Zr(acac)4).The effects of Zr on liquid phase oxidation of toluene were investigated by comparing the activities of cobalt acetate(Co),cobalt acetate and manganese acetate composite catalyst(Co/Mn) and cobalt acetate,manganese acetate and zirconium(IV) acetylacetonate composite catalyst(Co/Mn/Zr).The results showed that Zr could improve toluene conversion and benzoic acid selectivity under lower reaction temperature.Compared to other Co/Mn/Zr composite catalysts,the Co/Mn/Zr composite catalyst prepared using Zr(acac)4(zirconium(IV) acetylacetonate) as Zr source exhibited higher catalytic activity.The benzoic acid selectivity of 80.2% and the toluene conversion of 15.4% were reached,respectively,after reaction 3 h over the Co/Mn/Zr composite catalyst under the conditions of mass ratio of glacial acetic acid to toluene 1:2.3,molar ratio of Co to Mn and Zr 5:5:1,molar ratio of Co to toluene 1:10 000,reaction temperature 160 ℃ and reaction pressure 1.4 MPa.