The stability and O permeation behavior of Ce0.8Sm0.2O2−δ–La0.8Sr0.2CrO3−δ dual-phase composite were investigated under a large O gradient, with one side exposed to air and the other to CO, CH4 or H2 at high temperatures. An O permeation flux of 8.6 x 10−7mol/cm2s was obtained with a 1.1mm-thick membrane tube under an air/CO gradient at 950C, and no decrease in the flux was observed within a period of 110h. The O flux under an air/CO gradient was found to be about twice that under air/CH4 or air/H2 gradients. This could be attributed to the higher catalytic activity of the membrane towards the oxidation of CO. The membrane tube remained intact after high-temperature operation for over 1000h, and no significant changes in the phase composition or microstructure occurred.

Stability and Oxygen Permeation Behavior of Ce0.8Sm0.2O2−δ–La0.8Sr0.2CrO3−δ Composite Membrane under Large Oxygen Partial Pressure Gradients. B.Wang, J.Yi, L.Winnubst, C.Chen: Journal of Membrane Science, 2006, 286[1-2], 22-5