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Showing 1 to 10 of 10 for “"oxygen separation"”.
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Nanocrystalline perovskites for catalytic combustion and oxygen separation
Nanocrystalline perovskites (Lal-xAMnl-yByO3) were successfully synthesized with higher surface area and smaller grain size by chemical co-precipitation compared to solid-state and complexation/combustion synthesis routes. The choice of solvent, base and suspension pH in co-precipitation was found …
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Oxygen permeation and thermo-chemical stability of oxygen separation membrane materials for the oxyfuel process
… which consists in the burning of coal in an oxygen-rich atmosphere to produce a flue gas highly concentrated in CO2, is a technology considered for zero CO2 emission coal-fired power plants. The production of this O2-rich combustion gas from air can be carried out using high purity oxygen …
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Experimental characterization of an Ion Transport Membrane (ITM) reactor for methane oxyfuel combustion
… Membranes (ITM) which conduct both electrons and oxygen ions have been investigated experimentally for oxygen separation and fuel (mostly methane) conversion purposes over the last three decades. The fuel conversion investigations typically involve converting methane to syngas or higher …
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Sauerstofftransport und Degradationsverhalten von Hochtemperaturmembranen für CO 2-freie Kraftwerke
This thesis deals with membranes for oxygen separation from air for high temperature application in fossil power plants within the scope of the oxyfuel-process. Different perovskite membrane materials (ABO3-d) were investigated concerning the oxygen transport and their chemical stability under …
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An electrochemical study on the ionic conductivity of ceramic electrolyte La1-2SrxCo3-yMyO3-sigma oxide and its Pd/Ag compsites
… studied the electrochemical properties of the oxygen ceramic electrolytes of La1-xSrxCo1-yMyO3-d perovskite-type oxides that possess excellent electronic and oxygen anionic conductivity. Such mixed-conductivity is the essential property that the cathode material of solid oxide fuel cell (SOFC) …
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Charged-defect transport induced stress in mixed ionic-electronic conducting ceramic membranes
… of defect transport and stress, especially in oxygen-separation membranes. Varying the environmental oxygen pressure on the membrane surfaces induces transient responses of the charge-carrying-defect concentrations, electrostatic potential, and hydrostatic stress. The material properties for …
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Strukturelle und elektronische Untersuchungen am hoch sauerstoffdefizitären Mischleiter Ba x Sr 1-x Co 0,8 Fe 0,2 O 3-delta (BSCF)
… materials, such as superconductivity and high oxygen permeability, whereas these properties are also highly dependent on the surrounding oxygen partial pressure and temperature. In this family of materials, BSCF stands out as it accommodates an extremely high oxygen nonstoichiometry delta which …
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Defect chemistry, transport properties and thermodynamic stability of acceptor doped and undeoped layered La 2 NiO 4
The market for oxygen has grown significantly because many industrial processes require oxygen. At present oxygen is produced on industrial scale mainly by cryogenic distillation of air. This is a very energy intensive process and economic operation is possible only on a large scale. An alternative …
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Systems-level design of ion transport membrane oxy-combustion power plants
… combustion, particularly using an integrated oxygen ion transport membrane (ITM), is a thermodynamically attractive concept that seeks to mitigate the penalties associated with CO 2 capture from power plants. Oxygen separation in an ITM system consists of many distinct physical processes, …
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Oxygen transport in Ba(Fe,Co,Zr)O 3 - delta membranes
… is measured as a function of temperature and oxygen activity by TG. Very high nonstoichiometry (delta0=0.78 at a(O2)=1) is determined at 1273 K. From the nonstoichiometry of Ba(Fe,Co,Zr)O3-delta;, exponent n (n=-0.01) in Cv=C0v•a(O2)n, thermodynamic factor (gamma=140) and activation energy for …