SrCo0.9Sc0.1O3-δ perovskite hollow fibre membranes for air separation at intermediate temperatures

SrCo0.9Sc0.1O3 (SCSc) perovskite powders with sub-micron particle size were synthesized by a modified Pechini method combined with a post-treatment of sintering and ball-milling. From the prepared powders, the SCSc hollow fibre membranes with asymmetric structure and gas-tight property were fabricated by spinning a polymer solution containing 58.4 wt% SCSc followed by sintering at 1200 degrees C for 5 h. The oxygen permeation properties of the obtained SCSc fibres were measured under air/He gradients at 500-800 degrees C. This showed the oxygen flux of 1 mL cm(-2) min(-1) at 750 degrees C and 4.41 mL cm(-2) min(-1) at 900 degrees C. Modeling analysis reveals that the oxygen permeation process is predominated by oxygen surface exchange kinetics with an activation energy of 95.0 kJ mol(-1). The SCSc membranes showed excellent oxygen permeation performance while exhibiting high structural and permeating stability at intermediate temperatures (500-800 degrees C). (C) 2009 Elsevier Ltd. All rights reserved.