A novel cobalt-free CO2-stable perovskite-type oxygen permeable membrane

Abstract

A novel Cobalt-free perovskite dense oxygen permeable membrane with the composition Pr0.6Sr0.4Cu0.2Fe0.8O3-δ (PSCF) is designed and evaluated in this work. The XRD results reveal that the perovskite-type PSCF materials exhibit typical orthorhombic structure without any impurity phases. And PSCF powder exhibits excellent chemical stability in CO2 during high temperature annealing confirmed by HRTEM and thermogravimetric(TG) analysis. Upon the 20% Cu doping, the electrical conductivity of PSCF increases from 231.5 S cm−1 Pr0.6Sr0.4FeO3-δ (PSF) to 280.1 S cm−1 at around 773 K. Furthermore, the oxygen permeation flux through the dense PSCF membrane is evaluated and achieved 0.40 mL min−1 cm−2 swept by He at 1173 K for a 1.4-mm-thick membrane which is much higher than that of PSF membrane (0.17 mL min−1 cm−2). Meanwhile, the oxygen permeation of the PSCF membrane maintains a value of 0.16 mL min−1 cm−2 for more than 100 h at 1073 K with CO2 as sweep gas. The present results indicate that PSCF oxygen-permeable membrane is a promising chemically device for oxygen production with sufficiently high oxygen permeation flux.