Abstract: Gas-liquid phase oxidation of m-xylene under atmospheric pressure to prepare m-toluic acid was studied using oxygen as oxidant, cobalt acetate as catalyst and acetic anhydride as solvent. The effect of reaction conditions on the conversion of m-xylene and the yield of m-toluic acid was investigated and optimum conditions were obtained. It was found that under the optimum conditions of a m-xylene amount of 0.5 mL, a catalyst dosage of 0.05 g, a NaBr promoter dosage of 0.02 g, a solvent amount of 20 mL, an oxygen flow rate of 100 mL/min, a reaction temperature of 90℃ and a reaction time of 8 h, the conversion of m-xylene and the yield of m-toluic acid reached 100% and 98.36%, respectively.

Key words: m-xylene, m-toluic acid, atmospheric pressure, oxidation