High performanceBaCe0.8Y0.2O3-a (BCY) hollow fibre membranes for hydrogen permeation

Abstract

In this work, BaCe0.8Y0.2O3-a (BCY) perovskite hollow fibre membranes were fabricated by a phase inversion and sintering method. BCY powder was prepared by the sol–gel technique using ethylenediaminetetraacetic acid(EDTA) and citric acid as the complexing agents. Gel calcination was carried out at high temperature to form the desired crystal structure. The qualified BCY hollow fibre membranes could not be achieved even the sintering was carried out at temperatures up to 1550°C due to the poor densification behavior of the BCY material. The addition of sintering aid (1wt% Co2O3) inside BCY powder as the membrane starting material significantly improved the densification process, leading to the formation of gas-tight BCY hollow fibres. The optimum sintering temperature of BCY hollow fibre membrane was 1400°C to achieve the best mechanical strength. H2 permeation through the BCY hollow fibre membranes was carried out between 700 and 1050°C using 25% H2–He mixture as feed gas and N2 as sweep gas, respectively. For comparison purpose, the disk-shaped BCY membrane with a thickness of1 mm was also prepared. The measured H2 permeation flux through the BCY hollow fibres reached up to 0.38mL cm-2 min-1 at 1050°C strikingly contrasting to the low values of less than 0.01 mL cm-2 min-1 from the disk-shaped membrane. After the permeation test, the microstructure of BCY hollow fibre membrane was still maintained well without signals of membrane disintegration or peeling off.