METHOD FOR PURIFYING HIGH PURIFIED METHYL-4-FORMYLBENZOATE FROM BYPRODUCT OF DIMETHYL TEREPHTHALATE PREPARATION PROCESS

摘要

PURPOSE: A method for purifying methyl-4-formylbenzoate is provided to separately manufacture methyl-4-formylbenzoate with high yield and high purity from crude methyl-4-formylbenzoate, and to able to transform to methyl-4-formylbenzoate of high purity by only simple and cheap acid treatment. CONSTITUTION: A method for purifying methyl-4-formylbenzoate comprises: a step of adding alcohol to reaction side products containing methyl formylbenzoate, manufactured from a production process of dimethyl terephthalate, and filtering the outcome; a step of transforming methyl formylbenzoate to methyl-4-formylbenzoate in a filtrate through an oximation by adding hydroxylamine or inorganic acid salt, and alkali components to the filtrate, and filtering the outcome; a step of dissolving the methyl-4-formylbezoate mixture into an organic solvent; and a step of adding acid to the mixture.