Dawson型杂多酸钕盐催化氧化甲苯制备苯甲醛

合成了Dawson型磷钼钒杂多酸稀土(钕)盐,并用红外光谱分析(IR)、X射线衍射(XRD)方法对催化剂进行了表征;以H2O2为氧化剂,进行了甲苯氧化制备苯甲醛的反应研究.由于钕和钒的协同作用,催化剂表现出高的活性.实验结果表明,甲苯的转化率90.1%,苯甲醛的选择性达51.0%,双氧水的转化率89.0%,双氧水的有效利用率43.1%.基于对杂多酸盐结构的研究,对反应机理进行了初步的探讨.

Catalytic Oxidation of Toluene to Benzaldehyde over Dawson-type Heteropoly Acid Neodymium Salt

A novel Nd salt of Dawson type heteropoly acid(Nd3P2Mo15V3O62·nH2O) was prepared by doping rare-earth Nd in H9P2Mo15V3O62·nH2O,and characterized by infrared spectroscopy(FTIR),X-ray diffraction(XRD).Its catalytic activity was evaluated in the oxidation of toluene to benzaldehyde with H2O2 as an oxidant,the catalyst exhibits high activity owing to strong synergistic effect of Neodymium and vanadium.The conversion of toluene and the selectivity for benzaldehyde were up to 90.1%,51.0%,respectively.The conversion of H2O2 and effective utilization ratio of H2O2 were 89.0% and 43.1%,respectively.Based on the study of polyoxometalates’ structure,a possible reaction mechanism is proposed.