溶胶-凝胶法制备Fe2(MoO4)3超微粒子催化剂

以硝酸铁和钼酸铵为原料，采用溶胶－凝胶法和微波加热技术制备了F 2(MoO4)3超微子催化剂，使用DTA－TG，IR，XRD以及BET比表面测试等手段，考察了制备条件对复合氧化物超微粒子形成、晶相和比表面积的影响。同时测试了该样品对甲苯选择性氧化制苯甲醛的催化性能。结果表明：制备Fe2(MoO4)2超微粒子的适宜条件为：初始溶液pH=1.0,mol柠檬酸：mol(铁＋钼）＝0．4。在此条件下制得的干凝胶，经微波加热处理后粒子的比表面积为36.4m^2/g，粒径约为35nm。在由甲苯气相选择氧化制苯甲醛的反应中表现出较高的催化活性。

Preparation of Fe2(MoO4)3 Ultrafine Particle Catalyst By Sol-gel Method and Microwave Irradiation

Fe 2(MoO 4) 3 ultrafine particle catalyst was prepared from gel precursor on heating in microwave oven. The precursor was obtained from Fe 2(NO 3) 3 and (NH 4) 6Mo 7O 24 in citric acid. The influences of preparation conditions on the crystal phase and dimension of the particles were studied by using XRD, DTA TG, IR and BET surface area measurement methods. The activity and selectivity of the Fe 2(MoO 4) 3 catalyst for the selective oxidation of toluene to benzaldehyde was investigated. The results show that appropriate condition is citric acid/(Fe+Mo) molar ratio=0.4 and pH=1.0 for preparing Fe 2(MoO 4) 3 ultrafine particle. The BET surface area of the sample treated in microwave oven is 36.4m 2/g, the size is about 35nm. The catalytic activity of the sample prepared by sol gel method is higher than that prepared by precipitation method on the selective oxidation of toluene to benzaldehyde.