Partial Oxidation of Methane to Synthesis Gas Using Supported Ga-Containing Bimetallic Catalysts and a Ti-Promoter

A series of bimetallic Ga-containing materials using TiO2 and TiO2-promoted SiO2 supports have been prepared. Rhodium, palladium, and platinum have been used as additional metals in this system. The materials are characterized and used as catalysts for the partial oxidation of methane into synthesis gas (H-2 and CO). The presence of a low quantity of titanium in the form of anatase TiO2 was shown to improve the overall activity of catalytic methane oxidation and to strongly increase the selectivity of partial oxidation products over the total oxidation of methane to carbon dioxide and water. Particular attention is paid to the formation of gallium-metal alloys on the surface of the catalyst supports. Rh-Ga-Ti-SiO2 was found to be the most active and selective catalyst, giving 89% conversion of methane and 99% selectivity to synthesis gas at 750 degrees C, as well as exhibiting catalytic activity and preferential conversion to partial oxidation products at temperatures as low as 350 degrees C.