Catalytic wet peroxide oxidation of phenol solutions over CuO/CeO2 systems

Abstract

Three 5% CuO/CeO2 catalysts were synthesized by sol–gel, precipitation and combustion methods, followed by incipient wetness impregnation with copper nitrate. The samples were characterized by XRD, TPR, BET and tested for the catalytic wet peroxide oxidation of a phenol solution (5 g/L). The reaction took place in a batch reactor at atmospheric pressure, in a temperature range of 60–80 °C, during 4 h. Phenol conversion, H2O2 consumption, pH and chemical oxygen demand were determined. The reaction temperature and the catalyst loading did improve the phenol and the H2O2 conversions. The effect on the selectivity towards complete mineralization was less marked, with levels among 60–70%. Stepwise addition of H2O2 was also tested.