The promotion effect of tungsten on monolith Pt/Ce0.65Zr0.35O2 catalysts for the catalytic oxidation of toluene
Abstract
A mesoporous Ce0.65Zr0.35O2 support was synthesized via co-precipitation, and Pt/Ce0.65Zr0.35O2 and Pt-WO3/Ce0.65Zr0.35O2 catalysts were prepared through the incipient-wetness impregnation method for the catalytic oxidation of toluene. As evidenced by the catalytic activity results, the temperature for the complete conversion of toluene using the monolith Pt-WO3/Ce0.65Zr0.35O2 catalyst decreased by about 30 °C compared to that using Pt/Ce0.65Zr0.35O2. In addition, the physicochemical properties of the catalysts were characterized via N2 adsorption–desorption, XRD, H2-TPR, XPS and NH3-TPD experiments. The in situ DRIFTs technique was used to study the toluene catalytic oxidation process. The results showed that the excellent catalytic activity of Pt-WO3/Ce0.65Zr0.35O2 is ascribed to its good low-temperature reducibility, higher surface-adsorbed oxygen concentration, and greater medium strength acidity.