Catalytic combustion of methane over double perovskite Sr2Fe1-xMgxMoO6 mixed oxides

A series of double perovskite mixed oxide catalysts nominal Sr2Fe1-xMgxMoO6 was prepared with the sol-gel method and the properties of as-synthesized powders were characterized by XRD, BET, XPS, and TG. The catalytic activity of the Sr2Fe1-xMgxMoO6 for catalytic combustion of methane was tested in a pure oxygen atmosphere without dilute gas. The TG curves exhibit a typical two weight-loss processes similar to that of perovskite oxides. The results reveal that the catalytic activity of Sr2Fe1-xMgxMoO6 is affected by Fe/Mg ratio distinctly. It is suggested that substitution Fe ion with Mg results in the order of structure and the decrease of oxygen vacancy concentration on the surface, which is disadvantageous to the catalysis activity of methane combustion.