| Abstract
| - Tubular dense perovskite type membranes were prepared by isostatic pressing and plasticextrusion. The resulting tubular La0.6Sr0.4Co0.2Fe0.8O3-δ perovskite type membrane prepared byplastic extrusion (designated as PE-LSCF) has a lower density and oxygen permeation fluxcompared with that prepared by isostatic pressing (designated as IP-LSCF). A ceramic binderdeveloped by our research center provided reliable sealing for the tubular dense membrane athigh temperature. The oxygen permeation flux increases with increasing temperature, and thevalue is about 0.13 cm3/cm2 min (STP) at 1123 K. The activation energy for oxygen permeationis 168 kJ/mol at the temperature range of 1073−1173 K. X-ray diffraction analysis for themembranes over 110 h of operation indicated that SrSO4, CoSO4, SrO, Co2O3, and La2O3 wereformed on the surfaces of the tubular membrane, especially for the tubular PE-LSCF membrane,because of interaction with trace SO2 in the air and the helium and segregation of surfaceelements.
|
