Oxygen permeation, thermal and chemical expansion of (La, Sr)(Fe, Ga)O3−δ perovskite membranes
2008; Elsevier BV; Volume: 319; Issue: 1-2 Linguagem: Inglês
10.1016/j.memsci.2008.03.034
ISSN1873-3123
AutoresEnrique Juste, Aurélie Julian-Jankowiak, Grégory Etchegoyen, Pierre‐Marie Geffroy, Thierry Chartier, Nicolas Richet, Pascal Del-Gallo,
Tópico(s)Electronic and Structural Properties of Oxides
ResumoDense ceramic membranes made from mixed conductors are interesting because of their potential applications for methane conversion into syngas (H2 and CO mixture). Such membranes need to present a low differential dimensional variation between the opposite faces submitted to a large gradient of oxygen partial pressure, in order to minimize mechanical stresses generated through the membrane thickness. Besides, high oxygen permeability is required for high methane reforming rate. La(1−x)SrxFe(1−y)GayO3−δ materials fulfil these two main requirements and were retained as membranes in catalytic membrane reactors (CMR). The variations of expansion and oxygen permeation of La(1−x)SrxFe(1−y)GayO3−δ perovskite materials with the partial substitution of lanthanum and iron cations, temperature and oxygen partial pressure, were studied. For low temperatures ( 800 °C), TEC, then dimensional stability of the membrane, and oxygen permeation of La(1−x)SrxFe(1−y)GayO3−δ materials, are significantly affected by Sr content and oxygen partial pressure. Ga has a stabilisation effect on the TEC and has no influence on oxygen permeation flux. A good compromise between dimensional stability and oxygen permeation of materials was found to be La0.7Sr0.3Fe0.7Ga0.3O3−δ composition.
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