VPO催化剂催化乙苯氧化制苯乙酮

以V_2O_5和磷酸为原料,采用有机溶剂法制得VPO催化剂;利用XRD,IR,TPR方法对VPO催化剂的物相及可还原性进行了表征;以乙苯选择性氧化制苯乙酮为探针反应,对VPO催化剂的催化性能进行了研究。表征结果表明,所制得的VPO催化剂中主要有V~(4+)的(VO)_2P_2O_7物相和V~(5+)的VOPO_4物相,即催化剂中存在V~(5+)/V~(4+)离子对,为乙苯选择性氧化反应提供了催化活性中心。以冰醋酸为溶剂、H_2O_2为氧化剂,将VPO催化剂用于乙苯选择性氧化反应时,在乙苯用量10.0mL、冰醋酸用量10.0mL、双氧水(H_2O_2质量分数30%)用量10.0mL、VPO催化剂用量30mg、反应温度343K、反应时间2.5h的条件下,产物苯乙酮的收率可达17.2%。

Catalytic Oxidation of Ethylbenzene to Acetophenone over VPO Catalyst

VPO catalyst was prepared from vanadic oxide and phosphoric acid through organic solvent method,and characterized by means of XRD,IR and TPR to study the properties of the prepared VPO catalyst.The selective oxidation of ethylbenzene to acetophenone was used as probe reaction in order to investigate the catalytic behaviour of the VPO catalyst.The research results indicated that(VO)_2P_2O_7(V~(4+))and VOPO_4(V~(5+))were the main species in the prepared VPO catalyst,which were oxidation-reduction ion pair to be able to provide active center for the selective oxidation.Under the conditions of ethylbenzene dosage 10.0 mL,glacial acetic acid(as solvent) dosage 10.0 mL,hydrogen peroxide solution(mass fraction 30%,as oxidant)dosage 10.0 mL,VPO catalyst dosage 30 mg,343 K and 2.5 h,the yield of acetophenone was 17.2%.