Catalytic Properties Of Transition Metal Oxygen Acid Salt Containing Molybdenum,tungsten For Alcohol Oxidation Reaction

Polyoxometalates can designed at the atomic/molecular levels control of its constituent elements or transition metal atoms to change its performance. Efficient green catalyst for low price, good selectivity, mild reaction condition, high catalytic activity. Widely used in industry and has a high position in the field of catalysis. Therefore, they have received the widespread attention in recent year. This study mainly contains two parts:1、Prepared the Keggin type phase transfer catalyst of N-Hexadecyltrimethylam-monium Chloride as the counter-cations : [CTA]4 PW11 Co(H2O)O39, [CTA]4PW11Ni(H2O)O39, [CTA]4PMo11Ni(H2O)O39 and [CTA]10[(PW11NiO39)2O] four catalyst. And used as catalysts for the selective oxidation of liquid alcohols with hydrogen peroxide as an oxidant under solvent-free codition and aminent pressure. Rection temperature, the amount of catalyst, reaction time, benzyl alcohol and H2O2 molar ratio.Research shows that, the optimum conditions for the [CTA]4PW11Ni(H2O)O39 catalyst: 0.2 g, the molar ratio of benzyl alcohol and H2O2 was 0.8, the reaction temperature is 80 °C, the reaction time is 6 h, the conversion of benzyl alcohol was 95.11 %, selectivity of benzaldehyde was 93.03 %.The optimum conditions for the [CTA]4PW11Co(H2O)O39 catalyst: 0.3 g, the molar ratio of benzyl alcohol and H2O2 was 0.8, the reaction temperature is 60 °C, the reaction time is 5 h, the conversion of benzyl alcohol was 83.76 %, selectivity of benzaldehyde was 92.2 %.The optimum conditions for the [CTA]4PMo11Ni(H2O)O39 catalyst: 0.3 g, the molar ratio of benzyl alcohol and H2O2 was 0.8, the reaction temperature is 80 °C, the reaction time is 4 h, the conversion of benzyl alcohol was 75.19 %, selectivity of benzaldehyde was 87.67 %.The optimum conditions for the [CTA]10[(PW11NiO39)2O] catalyst: 0.2 g, the molar ratio of benzyl alcohol and H2O2 was 0.8, the reaction temperature is 90 °C, the reaction time is 4 h, the conversion of benzyl alcohol was 96.73 %, selectivity of benzaldehyde was 94.6 %. Comparing the catalytic performance of three kinds catalyst under the optimum conditions of the reaction: the catalytic activity [CTA]4PW11Ni(H2O)O39 > [CTA]4PW11Co(H2O)O39 > [CTA]4PMo11Ni(H2O)O39.2、Prepared the catalyst [C16H33N(CH3)3]5[PMo10V2O40] and [C16H33N(CH3)3]4 [PMo11VO40] and it was characterized by using IR, UV, XRD and so on. Through the single factor experiment was conducted to study the effect of catalyst amount, benzyl alcohol and H2O2 molar ratio, reaction temperature, reaction time and reaction conditions on the hydrogen peroxide oxidation of alcohols. The results showed that the optimal reaction conditions of [C16H33N(CH3)3]5[PMo10V2O40]: 0.3 g catalyst, the molar ratio of benzyl alcohol and H2O2 was 1, the reaction temperature is 70 °C, the reaction time is 6 h. The catalyst conversion rate was 85.49 %, the selectivity of benzaldehyde was 93.7 %, and 2 times the catalytic performance had no obvious decline. The optimal reaction conditions of [C16H33N(CH3) 3]4[PMo11VO40]: 0.3 g catalyst, the molar ratio of benzyl alcohol and H2O2 was 1, the reaction temperature is 70 °C, the reaction time is 6 h. The catalyst conversion rate was 85.07 %, the selectivity of benzaldehyde was 90.4 %, and 2 times the catalytic performance had no obvious decline.In this paper, the preparation of catalyst have high catalytic activity. High selectivity, mild reaction conditions, and easy preparation, short reaction time, high yield. These are an excellent green catalysts.