Keggin型配合物H_5PMo_(10)V_2O_(40)催化剂催化氧化反应研究

Study on Catalytic Oxidatio Benzaldehyde to Benzoic Acid with Keggin Compound H_5PMo_(10)V_2O_(40)

以钼酸钠、偏钒酸钠、磷酸二氢钠为原料合成H5PMo10V2O40.通过IR进行表征,确认所合成的化合物中多酸阴离子仍保留Keggin结构.将新合成的H5PMo10V2O40杂多酸应用到苯甲醛氧化合成苯甲酸反应中,考察了催化剂用量、氧化剂30%H2O2的用量、反应时间、反应温度等对苯甲酸收率的影响.最佳工艺条件为催化剂苯甲醛=1.9×10-31(摩尔比),n(H2O2)n(苯甲醛)=6.5 1,反应时间2.5 h,反应温度80℃.苯甲酸的收率达到85%以上.

H5PMo10V2O40 was synthesized by sodium molybdate, sodium metavanadate and sodium dihydrogen phosphate. The structure analysis suggusted that heteropoly anion in this compound was reserved its Keggin structure by IR. By using H5PMo10V2O40 as the catalyst and 30% H2O2 as the oxidation,some factors,catalyst dosage,oxidant dosage, reaction time and reaction temperature ect., on the oxidation of benzaldehyde to benzoic acid were examined. The optimal reaction conditions were identified. Under conditions as molar ratio of n （catalyst） ： n （benzaldehyde） = i. 9 × 10^-3： 1, molar ratio of n （ H2O2）： n （benzaldehyde） = 6.5 ： 1, reaction time of 2.5 h, reaction temperature 80 ℃. The yield of benzoic acid achieves 85%.