Catalytic wet oxidation of glucose as model compound of wastewater over copper/rare earth oxides catalysts

Abstract

Catalytic wet oxidation (CWO) is a promising technology for the treatment of wastewater and abatement of organic waste, in which the unique characteristics of water at elevated temperatures and pressures are utilised. In this study, the catalytic wet oxidation reaction of glucose (model compound of carbohydrate) was evaluated using three different rare earth oxides; CeO2, Dy2O3, and Tb4O7 as catalyst supports to the active phase, Cu. The heterogeneous catalysts were prepared using the incipient wetness impregnation method. The catalysts performance was evaluated by comparing the results from catalysts characterization and the chemical oxygen demand (COD) removal efficiency of each catalyst. The highest COD conversion (80 %) was achieved with Cu/Tb4O7 catalyst prepared at a dopant solution concentration of 1.0 M. The COD results revealed that the introduction of Cu metal into the catalyst supports greatly enhances the catalyst activity. However, leaching was detected in all catalysts, suggesting that the stability and reusability of the catalysts were low.