Process for the production of benzaldehyde by the catalytic liquid phase air oxidation of toluene

摘要

The present invention relates to an improved process for the production of benzaldehyde with 40-50% selectivity by catalytic liquid phase air oxidation of toluene. The process involves providing a continuous flow of air in the presence of a catalyst, a co-catalyst, a promoter and a bromine source, and a carboxylic acid solvent selected from the group consisting of acetic, propionic, benzoic acids ranging between 0.05 to 0.3 wt. times with respect to toluene, at a temperature ranging between 60-130°C and pressures in the range of 1-10 bars for a period of 0.5-1.5 hours to obtain benzaldehyde (40-50%) along with other by-products. Preferably, the catalyst is selected from salts of Fe, Co, Mn, Mo and Ni, and the co-catalyst is selected from manganese or copper salts.