Preparation and characterization of mesoporous VOx–TiO2 complex oxides for the selective oxidation of methanol to dimethoxymethane

Mesoporous VOx–TiO2 with high surface areas were prepared using the procedure of evaporation-induced self-assembly combined with ammonia posttreatment. The samples were characterized by X-ray diffraction (XRD), laser Raman spectroscopy (LRS), transmission electron microscopy (TEM), N2 adsorption, temperature-programmed reduction (H2-TPR), microcalorimetry for the adsorption of NH3, and isopropanol probe reaction. Their catalytic activities were evaluated for the reaction of selective oxidation of methanol to dimethoxymethane (DMM). It was found that the VOx–TiO2 materials exhibited high surface areas with pore diameters of 4 nm. The vanadia species were highly dispersed in the VOx–TiO2 within 30 wt% VOx content, evidenced by the results of XRD and LRS. The VOx–TiO2 samples exhibited both surface acidic and redox properties. The surface acidity was further enhanced on the addition of SO42-. The catalyst SO42-/30VOx–TiO2 exhibited good performance for the selective oxidation of methanol (57% conversion) to DMM (83% selectivity) at 423 K.

Novel mesoporous VOx–TiO2 oxides with pore diameters of 4 nm were synthesized, which exhibited good performance for the selective oxidation of methanol to dimethoxymethane.Figure optionsDownload as PowerPoint slide