磷钨酸催化环己烯合成己二酸的研究

Study on Synthesis of Adipic Acid from Cyclohexene with Phospho-Tungstic Acid as Catalyst

工业上以环己醇和环己酮的混合物或环己醇为原料,以硝酸氧化制己二酸,该法释放出的大量的氧化亚氮(N2O)能生成酸雨和破坏臭氧层。本研究旨在提供一种高选择性、高产率、环境友好的催化合成己二酸的方法。我们采用相对价廉易得的n-C16H33(CH3)3N·Br作相转移催化剂,原位合成12-磷钨酸作催化剂,1,2-二氯乙烷作有机溶剂,用浓度为30%的过氧化氢氧化环己烯,催化合成己二酸,收率最高达95.4%,选择性100%(GC7890F检测)。同时考察了反应时间、双氧水用量、酸度、溶剂1,2-二氯乙烷用量以及环己烯/相转移剂等因素对反应的影响。

The traditional industrial method of production of adipic acid at present is HNO_3 oxidation method with a mixture of cyclohexenanol and cyclohexanone ,cyclohexanol as raw materials. The large amount of N_2O emission produced from this process causes acid rain and ozone layer depletion. A green route of adipic acid production by oxidation cyclohexene is studied,in which cyclohexene is catalyzed by 12-phospho-tungstic acid, synthesized in situ with 30% hydrogen peroxide and n-C_(16)H_(33)(CH_3)_3N·Br is used as efficient phase transfer agent at reflux temperature. After collection by filtration and drying in air, colorless pure adipic acid is obtained with max. yield of 95.4% and selectivity of 100% as determined by GC method. Meantime, a series of experiments is carried out to determine the five factors reaction time, quantity of 1,2-dichloroethane and H_2O_2 used,pH value, ratio of cyclohexene and phase transfer agent, influencing the reaction.