PREPARATION METHOD OF AROMATIC CARBOXYLIC ACID

摘要

PURPOSE: A method for preparing an aromatic carboxylic acid is provided, to obtain the aromatic carboxylic acid which is improved in the light transmittance when dissolved in a basic aqueous solution by inhibiting the contamination due to the reaction intermediates and the materials produced in side reactions, simply and efficiently. CONSTITUTION: The method comprises the step of oxidizing an alkyl aromatic compound with molecular oxygen in a liquid phase in the presence of an oxidation catalyst in a reaction solvent containing a lower aliphatic carboxylic acid. The oxidation catalyst comprises heavy metal compounds and bromides. The amount of hydrogen used in the hydrogen gas process is 0.000001-0.5 L based on 1 g of the total amount of the solvent and the catalyst. Preferably the carboxylic acid is terephthalic acid.