Regulation of SBA‐15, γ‐Al2O3, ZSM‐5 and MgO on Molybdenum oxide and Consequent Effect on DME Oxidation Reaction

Abstract

AbstractMoO3 supported on SBA‐15, γ‐Al2O3, ZSM‐5 and MgO were prepared in this paper, the regulation of the support on the molybdenum oxide was explored. When the same molar ratio of MoO3 was loaded, three dimensional MoO3 were formed only over SBA‐15, γ‐Al2O3 and ZSM‐5, while MoOx domains were detected over MgO. Mo6+ species detected on SBA‐15, γ‐Al2O3, ZSM‐5 and MgO were almost at the same binding energy position while surface oxygen species detected on the surface were obviously at different position of binding energy. The amount of lattice oxygen predominates in the surface oxygen species of MoO3‐γ‐Al2O3 and MoO3‐MgO while the surface hydroxyl groups have most amounts in MoO3‐SBA‐15 and MoO3‐ZSM‐5. The surface acid property of the support rather than pH value of impregnating solution makes more contributions to governing the ratio of tetrahedral or octahedral molybdenum oxide. High content of lattice oxygen and more amounts of Lewis acid in γ‐Al2O3 are apt to form formaldehyde, and high content of surface hydroxyl group and more amounts of Bronsted acid sites in ZSM‐5 are in favor of the formation of methanol.