Complete catalytic oxidation of o-xylene over Mn–Ce oxides prepared using a redox-precipitation method

A series of Mn–Ce oxides were prepared using a redox-precipitation method and the complete catalytic oxidation of o-xylene was examined. Catalytic activity was evaluated in terms of both o-xylene conversion and CO2 yield. The effects of the Mnat/Ceat atomic ratio and calcination temperature on the features of catalyst structure and catalytic behavior were examined. When the Mnat/Ceat ratio was 1.5 and the catalyst was calcined at 400 °C, the conversion of o-xylene was 100% and the CO2 yield was 100% at 240 °C. X-ray diffraction (XRD), X-ray fluorescence (XRF), X-ray photoelectron spectroscopy (XPS), and hydrogen temperature-programmed reduction (H2-TPR) studies revealed that the catalysts prepared via the redox-precipitation method possessed a homogenous dispersion of amorphous MnO2 and CeO2 nanoparticles; in the main active phase, MnO2 provided available oxygen species and CeO2 enhanced oxygen mobility. The synergistic effects between MnO2 and CeO2 potentiated the catalytic activity necessary for the complete catalytic oxidation of o-xylene.