V-P-O/SiO_2催化剂上苯氧化的ESR研究  

ESR Study of Benzene-Oxidation on V-P-O/SiO_2 Catalysts

作　　者：刘加庚[1] 马福泰[2] 徐元植[3] 

机构地区：[1]南京化工学院科研处 [2]杭州大学化学系 [3]浙江大学化学系

出　　处：《高等学校化学学报》1990年第6期628-632,共5页Chemical Journal of Chinese Universities

摘　　要：用浸渍法制备组成通式为(V_2O_5)_(20)(P_2O_5)_2(SiO_2)_(100)(0<x<60)的12种催化剂,并评价了活性和选择性,测定了各催化剂中钒的平均氧化数、四价钒含量及钒的价态分布。考察此系列催化剂上苯的气相催化氧化反应可知,催化剂活性与V^(5+)及V^(4+)之和有关,而顺酐选择性则与V^(4+)相关。The catalysts with the compositions (V2O5)2o(P2O5)x(SiO2)100(0<x<60) were prepared by impregnation method. The catalytic properties of benzene oxidation on these samples were measured in a micro-reactor. The average oxidation numbers of V and the content of V4+ were determined by potassium permaganate titration and ESR, respectively. Thus the contents of V4+ and V3+ were calculated and the results were related to the catalytic property. It is found that the conversion of benzene and the selectivity to MA in the reaction were related closely to the total content of V5+ + V4+ and the content of V4+, respectively. By comparing the variation of the average oxidation numbers before and after reaction , we have come to the conclusion that the first attack to the aromatic ring is made by the lattice oxygen (double-boned).

关 键 词：苯 氧化 钒磷催化剂 氧化数 价态 

分 类 号：TQ225.23[化学工程—有机化工]