Abstract: Methods of and apparatus for generating high purity oxygen. Employed for this purpose is a "membrane cell" comprised of a praseodymia-modified, yttria-stabilized zirconia film that is fabricated onto a porous support, typically a tube of calcia-stabilized zirconia. This cell has the capability of "pumping" oxygen. As a consequence, oxygen in a pressurized fluid stream on the outer face of the membrane can be extracted from that stream and pumped as oxygen ions through the membrane without parasitic electric power and then released on the opposite side of the porous support tube as pure (electrolytic grade) oxygen. Extraction of pure oxygen continues as long as an oxygen partial pressure differential is maintained across the mixed conduction, "shorted" membrane. Oxygen thus produced can be used in industrial processes--for example, in coal gasification--or for other purposes.

Abstract: An electrochemical device (10) capable of generating oxygen from air (23) upon application of an electrical current, is made containing a plurality of adjacent cells (12) and (12') electrically connected in series, where each cell contains optional support (22), inner, porous oxygen electrode (20), dense, solid oxide electrolyte (14) on top of the inner oxygen electrode, and outer, porous air electrode (16) on top of the electrolyte, where dense segments of interconnection material (18) are disposed between cells, the interconnection electrically connecting the outer air electrode from one cell to the inner oxygen electrode from an adjacent cell, where the device contains gas impermeable, dense, contacting segments of electrolyte (14) and interconnection material (18) and can contain two end portions at least one of which provides for oxygen delivery.