화학공학소재연구정보센터
Journal of Membrane Science, Vol.459, 45-51, 2014
Oxygen permeability and structural features of SrFe1-xWxO3-delta membranes
The dependence of oxygen permeability of the new SrFe1-xWxO3-delta (SEW) membrane materials on temperature, oxygen partial pressure and membrane thickness was studied. The oxygen fluxes of SFW perovskite membranes was found to be controlled by the surface exchange reactions between 850 degrees C and 950 degrees C based on the dependence of oxygen permeation on the oxygen partial pressure. This result is in agreement with that from the thickness independence of the oxygen permeation flux. The deposition of A,g and a porous layer on the permeate side of the SrFe0.95W0.05O3-delta membrane leads to an increase in the oxygen fluxes by a factor of 1.8-23 compared with the oxygen permeability of the membrane with a non-modified surface. The stability of the oxygen fluxes across SrFe1-xWxO3-delta membranes was studied under air/He and air/CO2 gradients. The structure of membrane materials at low pO(2) was studied. A specific microstructure in which oxygen vacancies are ordered inside nanosized brownmilleiite-type domains was shown to be formed at x=0.05. (C) 2014 Elsevier RV. All rights reserved.