Catalytic combustion of volatile organic compounds on gold/cerium oxide catalysts

Abstract

Catalytic combustion of some representative volatile organic compounds (VOCs) (2-propanol, methanol and toluene) was investigated on gold/cerium oxide catalysts prepared by coprecipitation (CP) and deposition–precipitation (DP). The presence of gold has been found to enhance the activity of cerium oxide towards the oxidation of the selected volatile organic compounds, the extent of this effect depending on the preparation method of gold catalysts. On the basis of characterisation data (H2-TPR, X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRD), BET surface area) it has been suggested that the catalytic activity of the Au/CeO2 system is related to the capacity of gold nanoparticles to weaken the surface CeO bonds adjacent to Au atoms, thus enhancing the reactivity of the CeO2 surface capping oxygen which is involved in the volatile organic compounds oxidation through a Mars-van Krevelen reaction mechanism.