Research on catalytic oxidation of dimethyl ether to dimethoxymethane over MnCl2 modified heteropolyacid catalysts

The catalytic oxidation of dimethyl ether (DME) to dimethoxymethane (DMM) was carried out over MnCl2 modified different heteropolyacid catalysts. Kinds of supports and the catalyst packing structure were investigated. Besides, the possible reaction pathway of DME direct-oxidation to DMM was also discussed. The results showed H4SiW12O40/SiO2 Modified with MnCl2 exhibited a better catalytic performance than other heteropolyacids. SiO2 is the better supporting materials than the materials used as support. The synergistic effects of the acid sites offered by H4SiW12O4 and the redox sites mainly offered by MnO2 significantly improve the catalytic activity,of the catalyst. (C) 2008 Elsevier B.V. All rights reserved.