ZHANG Guangjun, WANG Weijie, WANG Lian, HOU Zhaoyu, BAO Xiaonan, ZENG Fanrong,
HU Guangzhou, WANG Shaorong
(School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China)
Abstract: Bi0.7Er0.3O3 (ESB) powder was prepared by solid reaction method and is used as the oxide ion conducting phase. Combining with La0.8Sr0.2MnO3 (LSM) as the electronic conducting phase, ESB –LSM dual-phase oxygen permeable membrane was prepared by pressing and sintering. The phase of ESB and its compatibility with LSM were characterized by X-ray diffraction (XRD) and the microstructure of the dualphase composite ceramic oxygen separation membrane was observed using scanning electron microscope (SEM). Finally, the oxygen transmission performance was tested by an electrochemical method. The results showed that the solid reaction method could produce single phase powder of ESB. The oxygen partial pressure, temperature and the ratio of oxide ion and electron conductive phases all had influence on the oxygen permeation rate through the ceramic membrane. When air was used as sweeping gas on the ESB–LSM dual-phase membrane, with mass ratio of 8 : 2, the oxygen permeation rate was 1.95 × 10-7 mol • cm-2 • s-1, 2.33 × 10-7 mol • cm-2 • s-1, 2.90 × 10-7 mol • cm-2 • s-1 and 3.37 × 10-7 mol • cm-2 • s-1 at 650 ℃, 700 ℃, 750 ℃ and 800 ℃, respectively.
Key words: dual-phase composite conductor; ceramic oxygen permeable membrane; oxygen permeation rate