Fenton-like oxidation of benzoic acid using Fe3+ doped physically activated walnut shells as a catalyst

Abstract

In this study, the degradation of benzoic acid by Fenton-like process was investigated over a Fe³⁺ doped on activated carbon catalyst. The walnut shells were activated by physical activation method and Fe³⁺ ions were doped by wet impregnation. The initial concentration of benzoic acid in degradation experiments was 50 mg/L. The effects of operation parameters such as hydrogen peroxide concentration, catalyst loading, temperature, and pH were examined. The optimum values of these parameters were found as 3 mM for hydrogen peroxide concentration, 0.1 g/L for catalyst loading,  approximately 25°C for (room) reaction temperature without pH adjustment (pH=4). At these conditions, approximately 10-15% degradation was achieved. It was concluded that since very low degradation efficiencies were achieved, the catalyst prepared, was not very active in the treatment of benzoic acid. For the ongoing experiments, it is planned to prepare the activated carbon by chemical activation based on using chemical reagents.