Integration of ITM Oxygen with a Decarbonized Fuel Plant for Co-production of Hydrogen and Clean Electric Power
Publication Date: 2003-Sep-12
The IP.com Prior Art Database
The Ion Transport Membrane (ITM) Oxygen process uses nonporous, mixed-conducting, ceramic membranes that have both electronic and oxygen ionic conductivity when operated at high temperature, typically 800 to 900 ºC. The mixed conductors are inorganic mixed-metal oxides that are stoichiometrically deficient of oxygen, which creates oxygen vacancies in their lattice structure. Oxygen from the air feed adsorbs onto the surface of the membrane, where it dissociates and ionizes by electron transfer from the membrane. The oxygen anions fill vacancies in the lattice structure and diffuse through the membrane under an oxygen chemical-potential gradient, applied by maintaining a difference in oxygen partial pressure on opposite sides of the membrane. At the permeate surface of the membrane, the oxygen ions release their electrons, recombine, and desorb from the surface as oxygen molecules. Since no mechanism exists for transport of other species, the separation is 100% selective for oxygen, in the absence of leaks, cracks, or flaws in the membrane.