Methanol Oxidaiton over the Nanoscale Supported Tungsten Oxide Catalysts

Nanoscale supported tungsten oxide catalysts were synthesized by hydrothermal method using γ-Al 2 O 3 , Nb 2 O 5 , TiO 2 , ZrO 2 and CeO 2 as supports with a loading of 5~20% WO 3 on each supports, respectively. The physical properties and structural information were characterized by BET, XRD, ICP-AES and in situ Raman spectroscopy. Raman results confirm that the desired molecular arrangements of the active surface WO x species have been achieved without the presence of the crystalline WO 3 phase. The reactivity/selectivity of the supported WO x catalysts are chemically probed with steady-state methanol oxidation reaction. The catalytic results of methanol oxidation reaction have revealed that the acid sites are present on the surface of WO x /Al 2 O 3 , WO x /Nb 2 O 5 , WO x /TiO 2 and WO x /ZrO 2 catalysts for the mainly production of dimethylether (DME), and redox sites have only present on the surface of the WO x /CeO 2 catalysts for the oxidation production of formaldehyde (HCHO). In addition, the WO x /CeO 2 catalysts possesses the high redox reactivity and the WO x /Al 2 O 3 catalyst possesses the highest acid reactivity.