Compared with traditional techniques, such as cryogenic air separation and pressure swing adsorption, new technologies using oxygen transport membranes (OTMs) have gained attention during the past 20 years. This is driven by low-efficiency losses associated with oxygen generation in the background of carbon capture and storage concepts, such as the oxy-fuel process, which burns fossil fuels with pure oxygen to enable simple sequestration of CO₂. Although originally intended for novel power plant designs, OTMs are not limited to such applications—other potential applications include advanced metallurgy, syngas production, petrochemical products, and gas-to-liquid processes for natural gas.¹

OTMs consist of gastight mixed ionic–electronic conductors (MIEC) that allow simultaneous oxygen diffusion and electronic conductance through the crystal lattice. Thus, no external circuitry is required, and, in case of sufficient gas-tightness, perfect selectivity can be achieved.