Perovskite Membranes for Oxygen Separation and Oxy-Combustion Processes

Mixed oxides with the perovskite-like structure, possessing mixed electronic and ionic electrical conductivities, are proposed for dense ceramic membranes production for both oxygen separation and oxy-combustion processes. In the study three perovskite-type mixed oxides La0.6Sr0.4Fe0.8Co0.2O3+� (LSCF), Ba0.5Sr0.5Co0.8Fe0,2O3+� (BSCF) and La2Ni0.9Co0.1O4-� (LNC), considered to be the most promising materials due to high oxygen � uxes, are utilized for both plate and tubular membranes fabrication. For providing the appropriate efcie ncy of the oxygen production, the main role is played by thickness as well as outer surface development of membranes. On account of this, three congurations of plate membranes were tested, i.e. thick dense membranes, thin dense diaphragms on porous support and thick dense membranes coated on both sides with porous thin layers. Tubular membranes, more useful in industrial practice due to their larger effec- tive surface, mechanical stability and easiness of application, were prepared in two congurations, i.e. dense thin-walled tubes made by isostatic pressing and extrusion methods, as well as thin dense membrane, coated on the porous tube. The basic physicochemical proper- ties of the obtained diaphragms were determined. Some of them were characterised by the measurement of the oxygen permeationux.