Production of NMSBA from NMST Catalyzed by Co/Mn/Br and HPW@C Modified with ZnCl2 Solution

Abstract

Abstract2-nitro-4-methylsulfonylbenzoic acid (NMSBA) can be produced by oxidizing 2-nitro-4-methylsulfonyltoluene (NMST) with air catalyzed by Co/Mn/Br and phosphotungstic acid(HPW) loaded on activated carbon. This paper reports that the catalytic ability of the HPW@C catalyst in the oxidation of NMST to NMSBA can be improved by treating the activated carbon with ZnCl2solution. The best modification condition with ZnCl2solution is impregnating the carbon sample in 0.1 mol/L solution for 6 h followed by calcination at 600 °C for 4 h. The increase of the surface area and the acidic groups on the carbon surface enhances the catalytic ability of the HPW@C catalyst. The mesopores play an important role in the catalytic oxidation of NMST to NMSBA.