Novel SrCo_0.9W_0.1O_3‐δ Hollow Fiber Ceramic Membrane with Enhanced Oxygen Delivery Performance and CO₂ Resistance Ability

Abstract

The development of the CO 2 -resistant mixed ionic-electronic conducting membranes can significantly expand their application into many CO 2 involved processes, such as the oxycombustion process and green chemical synthesis in membrane reactors. In this work, the SrCo 0.9 W 0.1 O 3-δ (SCW) hollow fiber membranes were fabricated via a combined phase inversion and sintering method. The oxygen permeation flux of 4.18 mL min À 1 cm À 2 was achieved at 950°C when pure He was used as sweep gas, while this flux can be further improved by 20.81% after Ag modification of outside membrane surface. Furthermore, the oxygen permeation behavior under CO 2 in the sweep gas and surface morphology has been investigated.The oxygen permeation flux experienced a slight decline, then reached a plateau at 2.44 mL min À 1 cm À 2 during permeation evaluation of 70-100 hours at 900°C when swept by 10% CO 2containing gas mixture of 100 mL min À 1 . More interestingly, the oxygen permeation flux only exhibited 9.44% decrease of the original flux value after switching the sweeping gas back to He, which can be attributed to the formation of the porous layer on the inside surface of membrane. The porous layer would reduce the membrane thickness, meanwhile supply more inside membrane surface area, facilitating the oxygen permeation.

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

“…These MIEC membranes also have applications as membrane reactors for many important oxidative reactions to improve the product selectivity (if controlled by the reaction equilibrium) or purity without including nitrogen in the product system [16][17][18][19][20][21][22][23][24][25][26]. However, such advanced applications require the membranes to possess strong stability against some gases like NO x , CO 2 , H 2 , or hydrocarbons [27][28][29][30][31].…”

“…Many previous works in MIEC membranes employed the perovskite compositions of ABO 3 based on these doped SrCoO 3 including SrCo 0.8 Fe 0.2 O 3−δ , SrCo 0.9 Sc 0.1 O 3−δ , Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3−δ , and La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3−δ [31][32][33][34][35][36][37][38]. These highly permeable membranes can only be applied for pure oxygen production purpose using mild gas atmosphere under the oxygen gradient of air (high pressure)/oxygen (1 atm).…”

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

“…1,2 Especially, the mixed ionic electronic conductors (MIECs) with the properties of the simultaneous electronic/ionic conductivity, [3][4][5][6] seem to be the promising materials for preparing the O 2 permeation membranes because of their high O 2 permeation performance and good stability, especially perovskite and Ruddlesden-Popper oxides. Nowadays, tonnage O 2 can be obtained from the conventional cryogenic distillation technology for over 100 years.…”

“…In the last few decades, the O 2 separation through ceramic membranes exhibited the superiority and potential to replace the conventional oxygen production technology. 1,2 Especially, the mixed ionic electronic conductors (MIECs) with the properties of the simultaneous electronic/ionic conductivity, [3][4][5][6] seem to be the promising materials for preparing the O 2 permeation membranes because of their high O 2 permeation performance and good stability, especially perovskite and Ruddlesden-Popper oxides. [7][8][9][10][11][12][13][14][15][16][17][18][19] However, many applications, such as green chemical synthesis and oxycombustion, involve CO 2 gas with different concentration, which would react with the membrane to form carbonate, leading to the operation failure.…”