Influence of the structure of TiO2, CeO2, and CeO2-TiO2 supports on the activity of Ru catalysts in the catalytic wet air oxidation of acetic acid

Ru catalysts, supported on TiO2, CeO2, and CeO2-TiO2, were prepared by the impregnation method. The effect of the structure of the supports on the activity of Ru catalysts was investigated in the catalytic wet air oxidation (CWAO) of acetic acid under 230 degrees C and 5 MPa in a batch reactor. Physical properties including the surface area, crystalline phase, and surface components of the Ru catalysts were characterized by N-2 adsorption, X-ray powder diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The CeO2-based Ru catalysts had good activity, and the prepared RuO2/CeO2 catalyst showed markedly higher activity than the RuO2/CeO2-TiO2 catalyst. The surface structure, the high amount of chemisorbed oxygen on the catalyst surface, and the suitable pH(pzc) value of the supports played an important role in the activity of the Ru catalysts in CWAO of acetic acid.