PARTIAL OXIDATION OF CH4 TO SYNTHESIS GAS-USING AN RH-VERTICAL-BAR-YSZ-VERTICAL-BAR-AG ELECTROCHEMICAL MEMBRANE REACTOR

Partial oxidation of CH4 has been carried out using an electrochemical membrane reactor composed of an yttria-stabilized zirconia (YSZ) disc with the faces covered with Ag and Rh films. Synthesis gas was obtained continuously by feeding CH4 and O-2 over the Rh- and Ag-coated surfaces, respectively, at a low temperature of 773 K. It is likely that the partial oxidation of CH4 to CO-H-2 as well as the complete oxidation to CO2-H2O proceed on the Ph-coated surface. The reaction pathways are independent of each other as judged by the reaction behaviour in terms of the dependence on the applied voltage and the reaction time course. It is considered that the complete oxidation was achieved by the oxygen species appearing at the three-phase boundary of Ph\YSZ\ atmosphere through YSZ. Direct partial oxidation was realised by the oxygen species migrating from the three-phase boundary onto the Ph surface.