A process for the manufacture of benzoic acid is described. The process is based on the reaction of toluene in a liquid phase oxidation with an oxygen containing gas in the presence of a phase-transfer catalyst (a), a transitionn metal salt (b) and traces of a polar solvent, such as water, the molar ratio between (a) and (b) being in the range of between 0.25:1 to 1.5:1. The phase-transfer catalyst is selected from quaternary ammonium and phosphonium salts having a total carbon atoms in the range of 17 to 58, the anion bound thereto being selected from Br⁻, F⁻, Cl⁻, OH⁻, CH₃COO⁻ or HSO₄⁻. The benzoic acid produced is characterized by its very high purity and high conversion reaching generally values of above 95%.
描述了一种制造
苯甲酸的工艺。该工艺的基础是
甲苯在相转移催化剂(a)、过渡
金属盐(b)和微量极性溶剂(如
水)的存在下与含
氧气体发生液相氧化反应,(a)和(b)之间的摩尔比在 0.25:1 至 1.5:1 之间。相转移催化剂选自总碳原子数在 17 至 58 之间的季
铵盐和
鏻盐,与之结合的阴离子选自 Br-、F-、Cl-、OH-、CH₃COO- 或 HSO₄-。生产出的
苯甲酸具有纯度高、转化率高的特点,一般可达到 95% 以上。