Ceramic membrane perovskite

ABO3 perovskite-type oxides with transition-metal ions at the B-site have high ionic and electronic transport in the form of p or n semi-conductivity (mixed ionic and electronic conductivity), caused by different oxidation states of the transition-metal cation. For dense ceramic membranes, perovskite-type oxides with the following cations are preferred A = Ln (lanthanide ion), Ca, Sr, Ba B = Cr, Mn, Fe, Co, Ni, Cu. [Pg.1234]

It is well known that dense ceramic membranes made of the mixture of ionic and electron conductors are permeable to oxygen at elevated temperatures. For example, perovskite-type oxides (e.g., La-Sr-Fe-Co, Sr-Fe-Co, and Ba-Sr-Co-Fe-based mixed oxide systems) are good oxygen-permeable ceramics. Figure 2.11 depicts a conceptual design of an oxygen membrane reactor equipped with an OPM. A detail of the ceramic membrane wall... [Pg.53]

In Chapter 10, the use of membranes for different applications are described. One of the possible membranes for hydrogen cleaning is an asymmetric membrane comprised of the dense end of a proton conduction perovskite such as BaCe0 95 Yb0 05O3 5 and a porous end to bring mechanical stability to the membrane. In this case, it is possible to take from the slurry, obtained by the acetate procedure, several drops to be released over a porous ceramic membrane, located in the spinning bar of a spin-coating machine. Thereafter, the assembly powder, thin film porous membrane is heated from room temperature up to 1573 K at a rate of 2K/min, kept at this temperature for 12 h, and then cooled at the same rate in order to get the perovskite end film over the porous membrane [50],... [Pg.115]

GUr T.M., Belzner A. and Huggins R.A., A new class of oxygen selective chemically driven nonporous ceramic membranes. Part I. A-siie doped perovskites, J. Membr. Sci. 75 151 (1992). [Pg.494]

The mixed-conducting perovskite oxides have attracted particular interest for use as dense ceramic membrane to control partial oxidation of methane to C2 products or syngas. Such a process bypasses the use of costly oxygen since air can be used as oxidant on the oxygen-rich of the membrane. [Pg.507]

The considerations in this chapter were mainly prompted by the potential application of mixed-conducting perovskite-type oxides to be used as dense ceramic membranes for oxygen delivery applications, and lead to the following general criteria for the selection of materials... [Pg.510]

It has been reported [22] that micro/nano surface reactive layers introduced on the surface of oxygen ion transport membranes enhanced the oxygen permeability of dense oxygen-permeable perovskite-type ceramic membranes, Lao.7Sro.3Gao.6Feo.403 6. The results also showed that the oxygen permeation flux is influenced by the surface area of the surface-reactive layer. [Pg.12]

General Properties of Perovskite-structured Proton-conducting Ceramic Membranes 51... [Pg.51]

General Properties of Perovskite-strucUired Proton-conducting Ceramic Membranes 57... [Pg.57]

An ideal membrane must have high electronic and protonic conductivities it should be fairly thin (1-10 pm), and chemically stable for prolonged periods of time under the presence of various gases such as CO2, H2O and H2S etc. The low electronic conductivity limits the H2 flux of the protonceramic membranes. Under pure H2 atmosphere at 900 "C, the protonic conductivities of SCYb and BCNd are about 0.7 x 10 2 and 2.2 x 10 2 S cm , respectively. These values are sh tly lower than the oxygen ionic conductivity of yttria stabilized zirconia (YSZ) or lanthanum strontium cobaltite (LSC) perovskite-type ceramics in air at the same temperature, so that there is room for further improvement in protonic conductivity. [Pg.72]

Air separation membranes are typically dense ceramic (typically perovskite) membranes, which selectively permeate oxygen in ionic form. Over the past two decades. Air Products (ITMs) and Praxair (oxygen transport membranes [OTMs]) have worked towards the commercial scale-up of these membranes for applications in power generation, gasification, and gas to liquid conversion [94]. Air Products has focused on a planar configuration, whereas Praxair on tubular membranes. [Pg.499]

The perovskite-type ceramic membranes have attracted much attention from major chemical and petrochemical companies in the USA. Companies currently involved in the development of the mixed-conducting ceramic membranes include Air Products, Praxair, BP and Amoco. The largest currently existing consortium developing this technology is headed by Air Products and sponsored by... [Pg.66]

In the last 20 years, the mixed oxygen-ionic and electronic conducting (MIEC) ceramic membranes such as Lai Sr Coi Fe Os perovskite that exhibit appreciable oxygen ionic and electronic conductivity at elevated... [Pg.253]

Tong, J., Yang, W., Zhu, B. and Cai, R. (2002) Investigation of ideal zirconium-doped perovskite-type ceramic membrane materials for oxygen separation. Journal of Membrane Science, 203, 175. [Pg.112]

Luo, H.X., Wei, Y.Y., Jiang, H.Q. et al. (2010) Performance of a ceramic membrane reactor with high oxygen flux Ta-containing perovskite for the partial oxidation of methane to syngas. Journal of Membrane Science, 350, 154-160. [Pg.114]

Lin Y S and Zheng Y (1996), Catalytic properties of oxygen semipermeable perovskite-type ceramic membrane materials for oxidative coupling of methane ,/ Catal, 164,220-231. [Pg.380]

Zeng Y, Lin Y S and Swartz S L (1998), Perovskite-type ceramic membrane synthesis, oxygen permeation and membrane reactor performance for oxidative coupling of methane , Membrane Sci, 150,87-98. [Pg.382]

Ding H, Xue X, Liu X and Meng G (2010), High performance protonic ceramic membrane fuel cells (PCMFCs) with SmosSro.sCoOs.g perovskite cathode , 7 Alloys Compd, 494,233-235. [Pg.595]

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