Oxygen permeation study of perovskite hollow fiber membranes

The first oxygen permeation data of a dense hollow fiber perovskite membrane based on BaCoxFeyZrzO3 − δ are reported. The hollow fiber was prepared by a phase inversion process. Dense fibers were obtained with the following typical geometries: outer diameter, 800-900 μm; inner diameter, 500-600 μm; length, 30 cm. The O2-permeation through the hollow fiber perovskite membrane was studied in a high-temperature gas permeation cell under different operation conditions. The increase of the helium gas flow rate reduces the oxygen partial pressure (pO2) on the core side and a higher oxygen permeation flux is observed. High oxygen flux of 0.73 m3 (O2)/(m2 (membrane) h) was achieved at 850 °C under the operation parameters Fair (shell side) = 150 ml/min and FHe (core side) = 30 ml/min. The oxygen partial pressure dependence of the O2 permeation flux indicated an interplay of both surface reaction and bulk diffusion as rate limiting steps. During 5 days of permeation a high and stable oxygen flux was observed. X-ray diffraction patterns of fresh and spent membranes after the permeation measurements revealed that no degradation after oxygen permeation appears.