H_6P_2W_9Mo_9O_(62)·24H_2O催化清洁氧化环己酮合成己二酸

Clear oxidation of cyclohexanone to adipic acid catalyzed by H_6P_2W_9Mo_9O_(62)·24H_2O

通过水热法合成新型Dawson结构磷钨钼杂多酸催化剂,对催化剂进行FT-IR、TG-DTA表征,并用于催化30%H2O2氧化环己酮制备己二酸.通过正交实验确定了优化工艺条件,并探讨了反应机理.结果表明,当n(环己酮)∶n(过氧化氢)∶n(草酸)∶n(催化剂)=100∶400∶1.00∶0.15,反应温度100℃,反应时间5h,进行3次平行实验,己二酸平均收率为71.6%,纯度为99.7%.经蒸发浓缩,催化体系可重复使用5次,收率为50.3%.

Tungstomolybdophosphate acid with Dawson structure was prepared by hy- drothermal synthesis and characted by means of FT-IR, TG-DTA. The synthesis of a- dipic acid with cyclohexanone and 30 percent hydrogen peroxide was carried out as a probe reaction to study the catalytic activity. The main effects of the reaction were opti- mized with orthogonal experiments, the mechanism was proposed. The results showed that under the optimal condition, i.e. the mole ratio of C6H10O： H2O2： H2C2O4 ： H6P2W9Mo9O62·2gH2O= 100 ： 400 ： 1.00 ： 0.15, the reaction temperature was 100℃, irradiation time 5 h, the isolated yield of adipic acid could reach 71.6% and its purity was 99.7%. The filtration containing the catalyst could be concentrated by the rotary evaporation and be reused five times by easily separation of the product after reac-tion, the isolated yield of adipic acid was still above 50.3%.