YSZ-SrCo0.4Fe0.6O3-δ membranes for the partial oxidation of methane to syngas

The perovskite-related yttria-stabilized zirconia promoted SrCo0.4Fe0.6O3-delta (SCFZ) oxides were used to construct membrane reactors for the partial oxidation of methane to syngas (POM). The oxygen permeability study of the SCFZ membrane in the air/helium gradient showed that the apparent activation energy was about 69 +/- 5 kJ/mol at 1, 023 similar to 1,223 K, and the oxygen flux was controlled by the bulk diffusion and. surface exchange rate. In a cofeed reactor packed with SCFZ pellets and a blank SCFZ membrane reactor without any catalyst packing, the SCFZ oxides showed low catalytic activity for POM in the fixed-bed reactor and no POM catalytic activity in the membrane reactor. An SCFZ membrane reactor with NiO/Al2O3 catalyst was continuously running for over 220 h under constant operational conditions. While about 64% of methane was converted with 100% CO selectivity after reaching the steady state, the oxygen flux was about 10 times the value of the air/helium gradient, in the reactor packed with the catalyst. The oxygen flux of SCFZ membranes in the reducing atmosphere could be limited by the surface reaction rate at the reaction side.