摘要 |
A process for converting a carbon containing fuel and water vapor into a reformate gas that includes hydrogen, carbon monoxide and carbon dioxide, using water molecules that diffuse through a membrane by steam permeation reforming. The process includes providing a ceramic membrane comprising an oxide ceramic having intrinsic and extrinsic oxygen ion vacancies, and having first and second surfaces; where the oxide ceramic capable of reacting with gaseous water molecules at the first surface by the reversible reaction, H<SUB>2</SUB>O(g)+V<SUB>O</SUB><SUP>..</SUP>+O<SUP>x</SUP><SUB>O</SUB><img id="CUSTOM-CHARACTER-00001" he="2.79mm" wi="3.56mm" file="US07332237-20080219-P00001.TIF" alt="custom character" img-content="character" img-format="tif"/>2OH<SUP>.</SUP><SUB>O</SUB>; and the oxide ceramic capable of producing gaseous water molecules at the second surface by the reversible reaction, 2OH<SUP>.</SUP><SUB>O</SUB><img id="CUSTOM-CHARACTER-00002" he="2.79mm" wi="3.56mm" file="US07332237-20080219-P00001.TIF" alt="custom character" img-content="character" img-format="tif"/>H<SUB>2</SUB>O(g)+V<SUB>O</SUB><SUP>..</SUP>+O<SUP>x</SUP><SUB>O</SUB>; contacting water vapor with the first surface; contacting the reformate gas with the second surface, whereby solid state ambipolar diffusion of oxygen ion vacancies and protons across the membrane occurs; and the ambipolar diffusion produces a net diffusion flux of water molecules through the membrane from the first surface to the second surface.
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