Comparative investigation of dual-phase membranes containing cobalt and iron-based mixed conducting perovskite for oxygen permeation

CO2‐resistant SDC‐SSAF oxygen selective dual‐phase hollow fiber membranes

“…43 and Ce 0.8 Sm 0.2 O 2-δ -La 0.7 Ca 0.3 CrO 3-δ (SDC-LaCaCr). 44 Also included are the oxygen permeation fluxes of SDCbased dual-phase disk membranes: SDC-SSAF, 22 Ce 0.8 Sm 0.2 O 1.9 -Sm 0.6 Ca 0.4 CoO 3-δ (SDC-SCC), 45 Ce 0.8 Sm 0.2 O 1.9 -Sm 0.6 Ca 0.4 FeO 3-δ (SDC-SCF), 45 Ce 0.85 Sm 0.15 O 2-δ -Sm 0.6 Sr 0.4 Cr 0.3 Fe 0.7 O 3-δ (SDC-SSCF), 42 Ce 0.8 Sm 0.2 O 2-δ -SmMn 0.5 Co 0.5 O 3-δ (SDC-SMC), 46 Ce 0.8 Sm 0.2 O 2-δ -Sm 0.8 Ca 0.2 Mn 0.5 Co 0.5 O 3-δ (SDC-SCMC), 46 and Ce 0.85 Sm 0.15 O 2-δ -Sm 0.6 Sr 0.4 FeO 3-δ (SDC-SSF). 47 The data were collected between 800 C and 950 C and under P 0 O2 =P 00 O2 ratio of approximately 0.21/0.003 atm Electrical conductivity measurements between 650 C and 850 C revealed oxygen ions transport as the limiting step that governs the overall oxygen transport mechanism in SDC-SSAF.…”

Phase and microstructural characterizations for Ce0.8Gd0.2O2--FeCo2O4 dual phase oxygen transport membranes

“…Hence, x and y were calculated by Eqs. (16) & (17) and (18) & (19), respectively. The parameters a and b were known inputs, and the f and g were deduced from the characterized weight fraction from the XRD patterns (Table 4).…”

“…For example, it has been suggested for dual phase oxygen transport membranes that a minor phase should possess a volume fraction above 30 % to form percolation to obtain high ambipolar conductivity and oxygen permeability [1]. Besides, the grain size of the minor phase was recommended to be smaller or equal to that of the matrix phase [9,11,16]. However, for dual phase oxygen transport membrane with a minor phase volume of less than 30 %, good oxygen permeability was also reported, such as for 80 vol% Ce 0.8 Sm 0.2 O 2-δ : 20 vol% PrBaCo 2 O 5+δ with a fiber-shaped electronic conductive skeleton [17], and for 81.5 vol% Ce 0.8 Gd 0.2 O 2-δ : 18.5 vol% FeCo 2 O 4 with a multi-phase system consisting of the Ce 1-x Gd x O 2-δ' (0 < x < 0.2) (CGO) fluorite phase, the Fe y Co 3-y O 4 (0 < y < 2) (FCO) spinel phase, the CoO rock salt phase, and the Gd 0.85 Ce 0.15 Fe 0.75 Co 0.25 O 3 (GCFCO) perovskite phase [8].…”

Development of Robust Mixed‐Conducting Membranes with High Permeability and Stability

“…Its capacity to keep the structure although slightly deformed to accommodate different charges, allows continuous properties adjustment, e.g. high degree of oxygen non-stoichiometry and high ionic, electronic and even protonic conductivity [6][7][8][9][10][11][12]. All those features convert perovskites and perovskite-like materials in useful ceramic membranes for oxygen transport processes with potential applications in chemical reactions with academic and/or industrial interest.…”