Tin-doped perovskite mixed conducting membrane for efficient air separation
Access Status
Authors
Date
2014Type
Metadata
Show full item recordCitation
Source Title
ISSN
School
Collection
Abstract
In this study, we propose a new tin-doped perovskite oxide, BaCo0.7Fe0.2Sn0.1O3-δ (BCFSn0.1), as a promising alternative material for a ceramic oxygen-permeating membrane. A high energy ball milling-assisted solid-state reaction method is used for the material synthesis. The effect of tin doping on the structure, electrical conductivity, oxygen activity, oxygen bulk diffusivity and surface exchange properties of the materials, sintering behaviour, and oxygen permeability of the related membranes is systematically investigated via transmission electron microscopy (TEM), environmental scanning electron microscopy (E-SEM), thermo-gravimetric analysis (TGA), oxygen temperature-programmed desorption (O2-TPD) and electrical conductivity relaxation (ECR), and oxygen permeation test. The minor substitution of B-site cations in BaCo0.7Fe0.3O3-δ (BCF) with tin is found to be highly effective in improving oxygen flux of the resultant membrane. Under an oxygen gradient created by air/helium, BCFSn0.1 membrane reaches fluxes of 9.62 x 10-7 and 3.55 X 10-7 mol m-2 s-1 Pa-1 [STP], respectively, at 900 and 700 °C, in sharp contrast with the flux values of 4.42 x 10-7 and 2.84 x 10-8 mol m-2 s-1 Pa-1 for BCF membrane with the same thickness of 1 mm. Favorable permeation stability is also demonstrated for the tin-doped membrane, and oxygen bulk diffusion is the main rate-limiting step for oxygen permeation, indicating a further increase in fluxes by reducing the membrane thickness.
Related items
Showing items related by title, author, creator and subject.
-
Chan, J.; Zhang, K.; Zhang, C.; Tian, H.; Liu, Shaomin (2015)Mixed conducting perovskite membranes have the potentials to replace the conventional expensive cryogenic method to separate oxygen from air and improve the viabilities of these clean energy technologies which need pure ...
-
Xu, D.; Dong, F.; Chen, Y.; Zhao, B.; Liu, Shaomin; Tade, Moses; Shao, Zongping (2014)Cobalt-free perovskite-type oxides with the nominal composition of BaNbyFe1−yO3−δ (y=0.025–0.20) are synthesized and evaluated as materials used in ceramic membranes for oxygen separation. The effects of Nb-doping on the ...
-
Zhang, Z.; Chen, D.; Dong, F.; Shao, Zongping (2015)The simultaneous high oxygen permeability and high chemical stability of perovskites for use as oxygen transport membranes are of critical importance for applications in oxyfuel processes and as membrane reactors for ...