TiO2 nanotubes supported V2O5 for the selective oxidation of methanol to dimethoxymethane

Chlorine free mesoporous TiO2 nanotubes (TNT) with high surface areas were prepared and used to support V2O5. The addition of V2O5 increased the surface acidity of TNT, which was further enhanced by the addition of Ti(SO4)2. The materials were characterized by X-ray diffraction (XRD), laser Raman spectroscopy (LRS), transmission electron microscopy (TEM), N2 and O2 adsorption, X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (H2-TPR), and microcalorimetry and infrared spectroscopy (FTIR) for the adsorption of NH3. The catalytic behavior for the selective oxidation of methanol to dimethoxymethane (DMM) was evaluated. It was found that V2O5 was highly dispersed on TNT with the V2O5 loading lower than 20 wt%. The 6%SO42−/20%V2O5/TNT displayed the strong surface acidic and redox characters and exhibited excellent performance for the selective oxidation of methanol to DMM. The methanol conversion reached 64% with 90% selectivity to DMM over the SO42−/20%V2O5/TNT at 403 K.