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High - purity oxygen production from air using perovskite hollow fiber membranes / Fangyi Liang in Industrial & engineering chemistry research, Vol. 49 N° 19 (Octobre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 19 (Octobre 2010) . - pp. 9377–9384 Titre : High - purity oxygen production from air using perovskite hollow fiber membranes Type de document : texte imprimé Auteurs : Fangyi Liang, Auteur ; Heqing Jiang, Auteur ; Thomas Schiestel, Auteur Année de publication : 2010 Article en page(s) : pp. 9377–9384 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Production  pure  oxygen Résumé : The production of O2-enriched air and of high-purity oxygen was studied in a flow-through and in a dead-end permeator with BaCoxFeyZr1−x−yO3−δ (BCFZ) hollow fiber membranes at high temperatures using (i) pressurized air/O2-enriched air as feed, (ii) reduced pressure on the permeate side, and (iii) a combination of both. For the effective production of oxygen with a high space-time yield, a two-step process is proposed. In a first step, O2-enriched air with an oxygen concentration of 30−50 vol % is produced in a flow-through permeator from 1 bar of air as feed applying a vacuum pump to keep the pressure on the O2-enriched air side at about 0.12 bar. In a second step, pure oxygen is produced in a dead-end permeator using the O2-enriched air from step 1 as pressurized feed and using again a vacuum pump to establish a reduced oxygen pressure of about 0.05 bar on the permeate side. The oxygen permeation fluxes increase with increasing temperature, pressure on the feed side, and oxygen concentration in the fed O2-enriched air. An oxygen permeation flux of 10.2 cm3 (STP) cm−2 min−1 was reached using O2-enriched air with 50 vol % O2 at 5 bar as feed and reduced pressure of 0.05 bar on the permeate side at 900 °C. A high oxygen purity up to 99.9 vol % and high permeation rates of almost 10 cm3 (STP) cm−2 min−1 were obtained at 900 °C in a 150 h operation under the conditions of 0.05 bar on the oxygen side and oxygen-enriched air at 4 bar on the feed side. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101311g [article] High - purity oxygen production from air using perovskite hollow fiber membranes [texte imprimé] / Fangyi Liang, Auteur ; Heqing Jiang, Auteur ; Thomas Schiestel, Auteur . - 2010 . - pp. 9377–9384. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 19 (Octobre 2010) . - pp. 9377–9384 Mots-clés : Production  pure  oxygen Résumé : The production of O2-enriched air and of high-purity oxygen was studied in a flow-through and in a dead-end permeator with BaCoxFeyZr1−x−yO3−δ (BCFZ) hollow fiber membranes at high temperatures using (i) pressurized air/O2-enriched air as feed, (ii) reduced pressure on the permeate side, and (iii) a combination of both. For the effective production of oxygen with a high space-time yield, a two-step process is proposed. In a first step, O2-enriched air with an oxygen concentration of 30−50 vol % is produced in a flow-through permeator from 1 bar of air as feed applying a vacuum pump to keep the pressure on the O2-enriched air side at about 0.12 bar. In a second step, pure oxygen is produced in a dead-end permeator using the O2-enriched air from step 1 as pressurized feed and using again a vacuum pump to establish a reduced oxygen pressure of about 0.05 bar on the permeate side. The oxygen permeation fluxes increase with increasing temperature, pressure on the feed side, and oxygen concentration in the fed O2-enriched air. An oxygen permeation flux of 10.2 cm3 (STP) cm−2 min−1 was reached using O2-enriched air with 50 vol % O2 at 5 bar as feed and reduced pressure of 0.05 bar on the permeate side at 900 °C. A high oxygen purity up to 99.9 vol % and high permeation rates of almost 10 cm3 (STP) cm−2 min−1 were obtained at 900 °C in a 150 h operation under the conditions of 0.05 bar on the oxygen side and oxygen-enriched air at 4 bar on the feed side. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101311g

Oxidative coupling of methane in a BCFZ perovskite Hollow fiber membrane reactor / Oliver Czuprat in Industrial & engineering chemistry research, Vol. 49 N° 21 (Novembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 21 (Novembre 2010) . - pp.10230-10236 Titre : Oxidative coupling of methane in a BCFZ perovskite Hollow fiber membrane reactor Type de document : texte imprimé Auteurs : Oliver Czuprat, Auteur ; Thomas Schiestel, Auteur ; Hartwig Voss, Auteur Année de publication : 2011 Article en page(s) : pp.10230-10236 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Membrane  reactor  Hollow  fiber Résumé : A membrane reactor that incorporated hollow fiber in combination with an established catalyst was used for the oxidative coupling of methane (OCM). A perovskite membrane of the composition BaCoxFeyZrzO3-delta (BCFZ, x + y + z = 1) allows a controlled oxygen feed into the reactor over its axial length. Using this novel hollow fiber membrane reactor with a 2 wt % Mn/5 wt Na2WO4 on SiO2 catalyst as a packed bed around the fiber, oxygen separation from air and C-2 formation could be established at 800 degrees C with long-term stability. The highest C-2 selectivity of similar to 75% was observed at a methane conversion of 6% with a C2H4:C2H6 ratio of 2:1. The highest C2H4:C2H6 ratio of 4:1 and maximum C-2 yield of 17% was obtained at 50% C-2 selectivity. It is known from the literature that such results can be obtained without a catalyst in a similar membrane reactor only at temperatures 150 degrees C higher. ISSN : 0888-5885 En ligne : http://publica.fraunhofer.de/documents/N-146437.html [article] Oxidative coupling of methane in a BCFZ perovskite Hollow fiber membrane reactor [texte imprimé] / Oliver Czuprat, Auteur ; Thomas Schiestel, Auteur ; Hartwig Voss, Auteur . - 2011 . - pp.10230-10236. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 21 (Novembre 2010) . - pp.10230-10236 Mots-clés : Membrane  reactor  Hollow  fiber Résumé : A membrane reactor that incorporated hollow fiber in combination with an established catalyst was used for the oxidative coupling of methane (OCM). A perovskite membrane of the composition BaCoxFeyZrzO3-delta (BCFZ, x + y + z = 1) allows a controlled oxygen feed into the reactor over its axial length. Using this novel hollow fiber membrane reactor with a 2 wt % Mn/5 wt Na2WO4 on SiO2 catalyst as a packed bed around the fiber, oxygen separation from air and C-2 formation could be established at 800 degrees C with long-term stability. The highest C-2 selectivity of similar to 75% was observed at a methane conversion of 6% with a C2H4:C2H6 ratio of 2:1. The highest C2H4:C2H6 ratio of 4:1 and maximum C-2 yield of 17% was obtained at 50% C-2 selectivity. It is known from the literature that such results can be obtained without a catalyst in a similar membrane reactor only at temperatures 150 degrees C higher. ISSN : 0888-5885 En ligne : http://publica.fraunhofer.de/documents/N-146437.html