Catalytic conversion of methane into synthesis gas

This Ph.D. dissertation is dealing with catalytic conversion of methane into synthesis gas, a versatile feedstock for the methanol and Fischer-Tropsch syntheses and many other carbonylation, hydrogenation or reduction processes. Reactions investigated include partial oxidation of methane, CO₂ reforming of methane and combined partial oxidation and CO₂ reforming of methane. Research works cover the four areas of elucidation of reaction mechanism, clarification of reasons for catalytic deactivation, determination of structure-property relationships, and development of high performance catalysts.; On the partial oxidation of methane, we investigated the effect of support, the effect of metal precursor, the effect of support precursor, and the effect of interactions between metal and support on catalytic activity and stability. In addition, the nature of active sites was examined based on pulse experiments with CH₄/O₂ (2/1), and the reaction mechanism based on pulse experiments with CH₄/O₂ (2/1) and with CD ₄/O₂ (2/1).; On the CO₂ reforming of methane, we investigated the effect of support, the effect of metal precursor, the effect of calcination temperature used in the preparation of catalyst, and the effect of metal loading on catalytic activity and stability. We also investigate the relationships between carbon deposition and catalytic deactivation.; On the combined partial oxidation and CO₂ reforming of methane, we investigated the effect of support and the effect of metal precursor on catalytic activity and stability. The effects of reaction temperature, space velocity, and O₂/CO₂ ratio in the feed gases (while keeping the C/O ratio constant at 1/1) were also examined over the Co/MgO catalyst.; As a result, we have come up with a kind of new Co/MgO solid solution catalysts, which have been proved to provide high and stable activities for all the three methane-to-synthesis gas reactions.