Oxygen permeation through Ca-contained dual-phase membranes for oxyfuel CO2 capture

• Three dual-phase membranes were synthesized by the one-pot methods.
• Oxygen permeation fluxes of the dual-phase membranes increase with the content of calcium in the perovskite phase.
• The Ca-contained dual-phase membranes are CO2 tolerant in the investigated temperature range.

The integration of mixed ionic and electronic conducting (MIEC) membranes into the oxyfuel process can significantly reduce the energy penalty introduced by the CO2 capture. For this integration, a CO2 tolerant oxygen permeable membrane is required. Here, dual-phase membranes were prepared via a one-pot method containing a samarium doped CeO2 as the oxygen ionic conducting phase for ionic transport and a calcium doped perovskite SmCoO3 as the mixed conducting phase for both ionic and electronic transport. Both phases of the prepared membranes are spontaneously formed from the mixed precursors via a one-pot method, which indicates that both phases are chemical compatible with each other. The effects of Ca doping amount in the perovskite oxide on total conductivity, oxygen permeation flux, permeation stability as well as structural stability under CO2 atmosphere were investigated. All the experimental results indicate that the Ca-contained dual-phase membranes have high stability and permeation flux under the sweep of CO2.