V-Mo-O催化剂的制备及催化甲苯合成苯甲醛的研究  

V-Mo-O Catalyst Preparation and Catalytic Oxidation of Toluene to Benzaldehyde

作　　者：徐阳阳[1] 刘自力[1] 熊小龙[1] 崔斌[1] 

机构地区：[1]广州大学化学化工学院珠江三角洲水质安全与保护教育部重点实验室,广东广州510006

出　　处：《分子催化》2014年第1期39-46,共8页Journal of Molecular Catalysis(China)

基　　金：国家科学自然基金面上项目(项目批准号21276054)

摘　　要：甲苯低温液相催化氧化制备苯甲醛是最具有竞争力的苯甲醛绿色合成路线.我们研究了溶胶凝胶法制备的V-Mo-O催化剂在液相低温条件下选择性氧化甲苯制备苯甲醛的性能.结果显示,钒钼摩尔比和焙烧温度是影响催化剂的主要因素,当钒钼的摩尔比为6∶7,焙烧温度为500℃时,催化剂表现出最佳性能.物性表征显示,该条件下合成催化剂V-Mo-O晶体呈棒状结构,直径约700 nm,长度约6μm.体相主要以Mo6V9O40和MoO3相态存在.X光电子能谱表征显示,MoO3物种分散于结晶体外表面,这种不同氧化态钼物种的分层组装可能有助于氧物种的传递,有利于提高其催化性能.催化剂在80℃温度下,以双氧水为氧化剂,冰乙酸为溶剂,反应30 min,甲苯的转化率达到38.9%,苯甲醛的选择性为69.7%.A competitive benzaldehyde synthetic route was catalytic selective oxidation of toluene under mild condi- tions. Assessed V-Mo-O catalyst performance of selective catalytic oxidation of toluene under mild conditions, catalysts were prepared by the sol-gel method. The results showed that the molar ratio of vanadium molybdenum and calcination temperature had significant effects on the catalyst performance, When the molar ratio of vanadium mo- lybdenum was 6 ： 7, and the calcination temperature was 500 ℃, catalyst performance was the best. The results of SEM showed that Catalyst was rod structure, the diameter was about 700 nm ,the length was about 6μm , and the Mo6V9040 and MoO3 phase was observed. The results of XPS showed that the catalyst had MOO3, the different layers assembled with different oxidation state of Mo may contribute to the transmission of oxygen species, which led catalytic performance was improved. When the reaction temperature was 80 ℃, hydrogen peroxide was as the oxidant, ice acetic acid was as the solvent ,The reaction time was 30 rain , the conversion of toluene was 38.9% , the selectivity of benzaldehyde was 69.7%.

关 键 词：甲苯 苯甲醛 选择氧化 钒 钼 

分 类 号：O643.32[理学—物理化学]