Enhancing Oxygen Permeation via the Incorporation of Silver Inside Perovskite Oxide Membranes

Abstract

As a possible novel cost-effective method for oxygen production from air separation, ion-conducting ceramic membranes are becoming a hot research topic due to their potentials in clean energy and environmental processes. Oxygen separation via these ion-conducting membranes is completed via the bulk diffusion and surface reactions with a typical example of perovskite oxide membranes. To improve the membrane performance, silver (Ag) deposition on the membrane surface as the catalyst is a good strategy. However, the conventional silver coating method has the problem of particle aggregation, which severely lowers the catalytic efficiency. In this work, the perovskite oxide La0.8Ca0.2Fe0.94O3−a (LCF) and silver (5% by mole) composite (LCFA) as the membrane starting material was synthesized using one-pot method via the wet complexation where the metal and silver elements were sourced from their respective nitrate salts. LCFA hollow fiber membrane was prepared and comparatively investigated for air separation together with pure LCF hollow fiber membrane. Operated from 800 to 950 °C under sweep gas mode, the pure LCF membrane displayed the fluxes from 0.04 to 0.54 mL min−1 cm−2. Compared to pure LCF, under similar operating conditions, the flux of LCFA membrane was improved by 160%.

Insight into Steam Permeation through Perovskite Membrane via Transient Modeling

“…Perovskite oxides with special physical characteristic are widely applied in membrane separation (oxygen/hydrogen/carbon dioxide separation membranes) [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ], fuel cells [ 22 , 23 , 24 ], and other environment-related application areas [ 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 ]. Up to now, many studies have focused on the mechanism of perovskite oxide membrane for high-temperature gas separation in practical experiments; however, the research on the simulation of the gas separation process is still limited and inadequate.…”

“…For Equation 12, on Side A, the electric potential is set as zero, because this side of the membrane is linked to ground, and, on Side B, the electric displacement is set as net charge density in the membrane, which are shown in Equations (18) and (19).…”

Novel La 0.7 Sr 0.3 FeO 3 − δ /(La 0.5 Sr 0.5 ) 2 CoO 4 + δ composite hollow fiber membrane for O 2 separation with high CO 2 resistance

“…23 In our previous works, the generation of hetero-interface could also facilitate the O 2 transportation through surface-modified hollow fiber membrane (HFM). [26][27][28][29][30][31][32][33][34][35][36][37][38][39] In this work, La 0.7 Sr 0.3 FeO 3 − δ /(La 0.5 Sr 0.5 ) 2 CoO 4 + δ (Perovskite/Ruddlesden-Popper, LSF-LSC) composite membrane was developed with hollow fiber configuration. [26][27][28][29][30][31][32][33][34][35][36][37][38][39] In this work, La 0.7 Sr 0.3 FeO 3 − δ /(La 0.5 Sr 0.5 ) 2 CoO 4 + δ (Perovskite/Ruddlesden-Popper, LSF-LSC) composite membrane was developed with hollow fiber configuration.…”

“…24,25 The membrane with hollow fiber configuration is suitable for practical applications because of the high membrane area/volume ratio as well as thin membrane wall in comparison with the disk and tubular membranes, therefore, HFMs were employed for environmental application, such as water treatment, gas separation (O 2 , CO 2 , H 2 ), and further developed as membrane reactors. [26][27][28][29][30][31][32][33][34][35][36][37][38][39] In this work, La 0.7 Sr 0.3 FeO 3 − δ /(La 0.5 Sr 0.5 ) 2 CoO 4 + δ (Perovskite/Ruddlesden-Popper, LSF-LSC) composite membrane was developed with hollow fiber configuration. The conceptual advantage could be realized from "surface-coating" to "bulk-blending."…”

Special Issue on “Membrane Materials, Performance and Processes”

“…This special issue also shows the effect of materials on the performance of membranes. Tan et al [8] studied the intercalation of silver particles in the perovskite grains of dense ceramic membranes to improve oxygen ion conduction. In another work, Song et al [9] investigated the effect of porous ceramic substrate in the formation of porous carbon membranes for desalination application.…”