Application of a supported iron oxyhydroxide catalyst in oxidation of benzoic acid by hydrogen peroxide

Oxidation of benzoic acid was studied via Fenton-like reaction using an innovative supported γ-FeOOH catalyst. The decomposition kinetics of hydrogen peroxide was investigated first. Oxidation of benzoic acid by hydrogen peroxide was performed to understand the effects of initial pH and hydrogen peroxide dosage. The treatment efficiency of benzoic acid at an initial pH of 3.2 was higher than at initial pHs of 6.0 and 10.0; this can be partly explained by reductive dissolution of γ-FeOOH. Therefore, the extent of heterogeneous catalysis was evaluated. We found that the majority of oxidation occurred on the catalyst surface, with some occurred in the solution due to iron dissolution of the catalyst.