Effects of Preparation Method on the Characterization and CO Oxidation Activities of the Carbon-Supported CuO–CeO2 Catalysts

Carbon monoxide oxidation, which is important for many applications, was studied on Vulcan XC72 supported CuO–CeO2 catalysts. The effects of surfactant and solvent used in impregnation technique on the characterization and activities of the catalysts were investigated. During the impregnation process, water, 1-propanol, ethyl alcohol, acetone and ethylene glycol were used as solvents. Surfactant (CTAB) was used in order to improve the surface morphology of the catalysts, and distribute active components in the porous support structure. XRD, XPS, ICPOES, SEM–EDX, HRTEM and N2 physisorption analyses were used to characterize the catalysts. CO activity studies were done using a feed composition of 1% CO, 21% O2 and balance He, between the 50–200 °C reaction temperatures. N2 physisorption results showed that using surfactant significantly improves the surface area and average pore diameters of the catalysts. The main crystal phases obtained from XRD measurements present in the catalysts are CuO and CeO2. The lowest 50% CO conversion temperature was obtained with 5–45/50 CuO–CeO2/Carbon catalysts prepared with 1 propanol as solvent using surfactant-assisted impregnation method. 50% CO conversion decreases from 106 to 95 °C by increasing the weight ratio of CuO from 5 to 15%. Catalysts with 15–35/50 CuO–CeO2/Carbon composition which were prepared applying surfactant-assisted impregnation method using 1 propanol as solvent were found to be the most suitable catalysts for CO oxidation in this study.