Mechanistic evidences of the synthesis of methyl formate from methane and air on oxide catalysts

The direct conversion of methane into methyl formate with high molar yields (>12%) by a two reactor system has been attained. The reaction sequence co nsists of the partial oxidation of methane to HCHO at 600-700 degreesC (MPO ) on a "precipitated" SiO2 catalyst and the subsequent dimerization of HCHO to methyl formate (FD) at 130-170 degreesC on various oxide systems (TiO2, SiO2, ZrO2, SO42-/ZrO2). FTIR characterization of the oxide catalysts allo wed to highlight the superior performance of amphoteric oxides like TiO2 an d ZrO2 in the FD reaction arising from the presence of surface acid and bas e sites playing a synergetic role in the reaction pathway. (C) 2001 Elsevie r Science B.V. All rights reserved.