Synthesis and Characterization of 40 wt % Ce0.9Pr0.1O2–δ–60 wt % NdxSr1−xFe0.9Cu0.1O3−δ Dual-Phase Membranes for Efficient Oxygen Separation

Abstract

Dense, H2- and CO2-resistant, oxygen-permeable 40 wt % Ce0.9Pr0.1O2–δ–60 wt % NdxSr1−xFe0.9Cu0.1O3−δdual-phase membranes were prepared in a one-pot process. These Nd-containing dual-phase membranes have up to 60% lower material costs than many classically used dual-phase materials. The Ce0.9Pr0.1O2−δ–Nd0.5Sr0.5Fe0.9Cu0.1O3−δ sample demonstrates outstanding activity and a regenerative ability in the presence of different atmospheres, especially in a reducing atmosphere and pure CO2 atmosphere in comparison with all investigated samples. The oxygen permeation fluxes across a Ce0.9Pr0.1O2−δ–Nd0.5Sr0.5Fe0.9Cu0.1O3−δ membrane reached up to 1.02 mL min−1 cm−2 and 0.63 mL min−1 cm−2 under an air/He and air/CO2 gradient at T = 1223 K, respectively. In addition, a Ce0.9Pr0.1O2–δ–Nd0.5Sr0.5Fe0.9Cu0.1O3–δ membrane (0.65 mm thickness) shows excellent long-term self-healing stability for 125 h. The repeated membrane fabrication delivered oxygen permeation fluxes had a deviation of less than 5%. These results indicate that this highly renewable dual-phase membrane is a potential candidate for long lifetime, high temperature gas separation applications and coupled reaction–separation processes.

Recycling process development with integrated life cycle assessment – a case study on oxygen transport membrane material

“…The deviation is within the expected measurement error (±5%). 110 XRD confirmed the phase stability of LCNC after sintering (see Fig. S14 in ESI †).…”

Roadmap for Sustainable Mixed Ionic‐Electronic Conducting Membranes

“…[5,6] Oxygen permeable membranes have been intensively investigated in the past decades and can be generally grouped into two types: single-phase and dual-phase (see Figure 2). [1,2,[15][16][17][18][19][20][21][22][23][24]7,[25][26][27][28][29][30][31][32][33][34]8,[35][36][37][38][9][10][11][12][13][14] Currently, Ba-, Sr-, or Co-containing single-phase perovskite-type oxygen-transporting membranes (OTMs) with a general formula of ABO 3 show high oxygen permeation and generally have an oxygen permeation flux of more than 1 mL min −1 cm −2 at 1173 K for a 1 mm-thick membrane. [1,2] However, these OTMs have a poor stability in the presence of CO 2 due to the formation of carbonates.…”

“…[16] High performance of the dual-phase membranes consisting mixed ionic electronic conductors and ionic conductors has been obtained in the literature through optimization of the critical factors including phase ratio, grain size, conductivity, phase composition, phase distribution and gas-solid interfaces. [1,14,[36][37][38][15][16][17][18][29][30][31]35] Coating a catalyst layer or surface modifications on CO 2 resistant dual-phase and K 2 NiF 4 -type membranes can largely enhance the surface exchange kinetics resulting in the improvement of the oxygen permeability. [1,2,9] Still, these membranes have much lower oxygen permeability than perovskite-type oxygen permeable membranes despite having better chemical and phase stability.…”