Abstract: The tubular asymmetric membrane (TAM) was prepared by co-firing method with dense top layer of SrCo_0.8Fe_0.2O_3-δ(SCF) and porous substrate layer of (SrCo_0.8Fe_0.2O_3-δ)_0.85(SrSnO₃)_0.15 (SCF-SS). Its phase composition, morphology and oxygen permeability were investigated. The results show that SCF layer and SCF-SS layer have desirable compatibility for configuration of asymmetric membrane. The resulting TAM sample sintered at 1150℃ has the dense layer of SCF with thickness of 50μm and the SCF-SS substrate with apparent porosity of 19.3%. The permeation rates of the resulting TAM are 1.91mL·cm^-2·min^-1 at 900℃ and 1.01mL·cm^-2·min^-1 at 800℃, respectively, which are 24% and 36% higher than those of the SCF tubular symmetric membrane (TSM) with same size(wall thickness of 1.4mm, outer diameter of 10.3mm, and length of 4.1cm).

Key words: tubular asymmetric membrane, oxygen permeation, mixed ion and electron conducting, perovskite