Preparation and Characterization of Cu/SiO2 Catalyst and Its Catalytic Activity for Hydrogenation of Diethyl Oxalate to Ethylene Glycol

The Cu/SiO2 catalyst for gas-phase hydrogenation of diethyl oxalate (DEO) to ethylene glycol (EG) was prepared through the homogeneous deposition-precipitation method. The catalyst was evaluated at different reaction temperatures, pressures, and molar ratios of H2/DEO to optimize the catalyst preparation method and reaction conditions. Characterizations were carried out using various methods such as TPR, XRD, N2 adsorption, HRTEM, and SEM to study the thermal stability of the catalyst, the catalyst forming, and the distribution of the active site. From the results of these experiments, the best preparation method, Cu loading, reduction temperature, and reaction conditions were obtained. Under the optimized conditions, the DEO conversion and EG yield reached 94.8% and 76.0%, respectively.