The liquid-phase oxidation of o-xylene, catalysed by Co(II) acetate m acetic acid, has been studied at temperatures between 130–150 °C and an oxygen partial pressure of 300 kPa in a glass-lined semi-batch reactor. Online analysis of the reaction products was carried out by HPLC and time dependent concentrations of all products were obtained. Initially, o-xylene is oxidized to o-tolualdehyde, which in turn is oxidized to the relatively stable o-toluic acid. In addition, a series of nine other reaction products are formed. A mechanism involving the self-condensation of o-tolualdehyde has been proposed to account for the observed product distributions. Phthalide, one of the major products, is also formed by the direct oxidation of o-toluic acid, and most likely catalysed by the Co(II) acetate salt.

中文翻译：

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邻二甲苯的液相氧化：第一部分。产品分布和机理

在衬有玻璃的半间歇反应器中，在130–150°C的温度和300 kPa的氧分压下，研究了乙酸钴（II）对乙酸催化的邻二甲苯液相氧化。通过HPLC进行反应产物的在线分析，并获得所有产物的时间依赖性浓度。最初，邻二甲苯被氧化为邻甲苯甲醛，后者又被氧化为相对稳定的邻甲苯甲酸。另外，形成了一系列其他九种反应产物。涉及o的自凝聚的机制已经提出使用-甲苯甲醛来解释观察到的产物分布。邻苯二甲酸酯是主要产物之一，也是由邻甲苯甲酸直接氧化形成的，最有可能是由乙酸钴（Ⅱ）催化的。