Zr0.84Y0.16O1.92–La0.8Sr0.2Cr0.5Fe0.5O3−δ dual-phase composite hollow fiber membrane targeting chemical reactor applications

Gas-tight Zr0.84Y0.16O1.92 (YSZ) and La0.8Sr0.2Cr0.5Fe0.5O3−δ (LSCF) dual-phase composite hollow fibers were prepared by a phase-inversion/sintering technique. A high oxygen permeation rate of 3.8 ml cm−2 min−1 (STP), equivalent to 2.6 × 10−6 mol cm−2 s−1, was measured with a 4.46-cm long hollow fiber by exposing its shell side to air and feeding CO at 30 ml/min into its lumen side at 950 °C. The CO oxidation reaction occurring in the as-constructed membrane reactor was found to proceed at a high rate and full conversion of CO to CO2 was attained at the O2 to CO ratio of 0.5. A numerical simulation was applied to the membrane reactor assuming plug flow model and equilibrium condition. The hollow fiber survived after 500 h of the test, and no significant change to its microstructure was observed. Since the YSZ–LSCF hollow fiber exhibited both high oxygen permeability and stability under stringent conditions, it holds promise for membrane reactor applications.

► YSZ–LSCF dual-phase composite hollow fiber membrane has been prepared. ► The membrane exhibits high oxygen flux and stability under a large oxygen gradient. ► Full oxidation of CO can be attained with a hollow fiber membrane reactor.