Liquid-Phase Oxidation of Toluene to Benzoic Acid over Manganese Oxide Catalyst

Manganese oxide (Mn 3 O 4 ) catalyst was prepared by decomposition method and characterized by X-ray powder diffraction (XRD) and fourier transform infrared spectrum (FTIR). Catalytic activity of Mn 3 O 4 was tested by the oxidation of toluene to benzoic acid with molecular oxygen in liquid-phase and solvent free conditions. As a result, 45% conversion of toluene and 91% selectivity of benzoic acid was achieved. It is proved that Mn 3 O 4 catalyst can use several runs without decrease of activity.