High flux and CO2 stable La0.6Ca0.4Co0.2Fe0.8O3-δ hollow fiber membranes through internal coagulation bath optimization

La0.6Ca0.4Co0.2Fe0.8O3-δ (LCCF) ceramic powder prepared by sol-gel method was used to fabricate LCCF hollow fiber (HF) membranes via a combined phase inversion-sintering technique. Three types of LCCF HF membranes were developed by changing the composition of the internal coagulation bath containing H2O, EtOH or the mixture of NMP + EtOH. The best one was achieved via the mixture (0.7NMP + 0.3EtOH by weight). At 1000 °C, the oxygen flux reached 6.16 mL min−1 cm−2 under inert sweep gas; however, it reached 8.83 mL min−1 cm−2 when reactive CH4 was used as the sweep gas, mirroring the high capability of oxygen transport through the membrane. The good stability of the developed LCCF membrane was confirmed by a series of long-term operation tests up to 300 h with sweep gas containing CO2. The findings of this work can advance the applications of LCCF membranes to reactors where CO2 atmosphere cannot be avoided.