Thickness dependence of oxygen permeation through erbia-stabilized bismuth oxide-silver composites

Chen, C.S. and Kruidhof, H. and Bouwmeester, H.J.M. and Verweij, H. and Burggraaf, A.J. (1997) Thickness dependence of oxygen permeation through erbia-stabilized bismuth oxide-silver composites. Solid State Ionics, 99 (3-4). pp. 215-219. ISSN 0167-2738

Preview

PDF
448Kb

Abstract:	Oxygen permeation measurements were performed on erbia-stabilized bismuth oxide-silver (40 v/o) composite membranes in the range of thickness of 1.60–0.23 mm and temperature of 850–650 °C. Air was fed at one side of the membranes while permeated oxygen on the other side was swept away with helium. An oxygen flux as high as 1.56 × 10−7 mol/cm2/s was observed for a 0.23 mm thick membrane at 750 °C and Po2(1) = 0.056 arm. The examination of the dependence of permeance on the membrane thickness reveals that (a) the oxygen transport kinetics are controlled by the diffusion of oxygen ions in the bulk of membrane with thickness down to about 1.0 mm; (b) with further decrease in thickness, the oxygen permeation becomes partially limited by surface oxygen exchange. The surface exchange rate has been found to decrease less pronouncedly than the bulk process as temperature decreases. The mass transfer is suggested to be the rate-limiting step for the surface process.
Item Type:	Article
Copyright:	© 1997 Elsevier Science
Faculty:	Science and Technology (TNW)
Research Group:	Inorganic Membranes (IM)
Link to this item:	http://purl.utwente.nl/publications/12119
Official URL:	http://dx.doi.org/10.1016/S0167-2738(97)00271-3
Export this item as:	BibTeX EndNote HTML Citation Reference Manager

Repository Staff Only: item control page

Metis ID: 106503