Preparation and Characterization of Dual-Layer Hollow Fibre Catalyst Membrane for Oxygen Transport

摘要

Asymmetric pore configuration of dual-layer hollow fibre catalyst membrane of NiO-YSZ (inner layer)/La_(0.7)Sr_(0.3)Co_(0.2)Fe_(0.8)O_(3-δ)-YSZ (outer layer) has been studied from its morphology and oxygen transport point of view. The membrane was synthesized by phase inversion method and co-extruded using water as the external coagulant and water, ethanol and NMP mixture as the internal coagulant (bore liquid mixture), followed by sintering at 1300 °C for 8h. Volume ratio of water: ethanol:NMP was 4:1:5. The resulted dual-layer membrane has non-sandwich like pore configuration. SEM images of the membrane showed finger-like pores on the internal side and sponge-like pores on the external side. Bending strength of the membrane was 9.76 MPa and nitrogen permeability (gas tightness) was 1.36 × 10~(-4) mol.m~(-2).s~(-2).Pa~(-1). The oxygen permeability of the membrane at 600, 700 and 800 °C was 2.78 × 10~(-8), 2.84 × 10~(-8) and 3.10 × 10~(-8) mol.s~(-1) .cm~(-2), respectively, which is about two order of magnitude lower than oxygen permeability of other reported perovskite-based membranes.