Direct Partial Oxidation of Methane to Synthesis Gas Using Oxygen Carriers in the Absence of Gaseous Oxygen

Much attention has been paid to the reactions of the partial oxidation of methane ( POM) to synthesis gas in heterogeneous catalysis due to synthesis gas with a H2P CO ratio of ca. 2 , which is suitable for methanol and Fischer2 Tropsch synthesis. Direct partial oxidation of methane to synthesis gas using oxygen carriers as oxidant in the absence of gaseous oxygen is a new technology for the utilization of natural gas. The process principle , process concept , selection and requirements of oxygen carriers for methane oxidation are introduced. We summarize the latest progresses in CeO22 based oxygen carriers about dopants and promoters , and perovskite2based oxygen carriers about oxygen ion vacancy , oxygen migration , structural stability , and performance for direct partial oxidation of methane in the absence of gaseous oxygen. The product distribution for POM using oxygen carrier is determined by surface state , which can be optimized by controlling appropriate amounts of replenished lattice oxygen with gaseous oxygen. Moreover , the major problems and research directions in this area are proposed.