Hollow fiber membrane reactors for the oxidative activation of ethane

A dense perovskite hollow fiber membrane made of the composition BaCoxFeyZrzO3−δ (BCFZ, x + y + z = 1) was fabricated by a phase inversion spinning followed by sintering. The oxygen permeation was investigated by operating with minor mass transfer resistance and oxygen partial pressure on the shell side and the core side of the hollow fiber membrane which can be adjusted by varying the air flow rates on the shell side (25–300 mL/min) and He flow rates on the core side (25–150 mL/min). A co-feed reactor and a periodically operated fixed-bed reactor were employed to estimate the BCFZ catalytic activity for the oxidative dehydrogenation of ethane to ethylene (ODE). Broken pieces of BCFZ pellets used in a packed bed reactor show that this perovskite possesses a moderate catalytic activity for the ODE at low temperature. For the first time the ODE was investigated in a hollow fiber membrane reactor made of the BCFZ. The best ethylene selectivity is about 64% which is lower than the 79% obtained in the BCFZ disk-shaped membrane. The reason is that the contact time on the two membrane configurations is different and the deeper oxidation of ethylene/ethane to CO and CO2 cannot be avoided in the hollow fiber membrane reactor.