O2 Separation Using MIEC Membranes and Steam Circulation Process

MIEC (mixed ionic-electronic conductors) membranes are used to separate oxygen from air. In this article the functionality of these membranes with steam to produce high-purity oxygen is presented. Compared to other sweep gases, the utilization of steam with MIEC enables the decentral production of oxygen using mainly thermal energy. This is especially advantageous for small and medium-sized consumers; whereby they can produce their demand for oxygen through the recovery of waste heat at high temperatures and without extra transport costs. Therefore, a test rig was developed to investigate the MIEC membrane tubes made of Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) at different temperatures. The results of the experiments establish a proof of concept for this process.