Science · 2006 · 252 citations · 10 references
Natural SciencesChemical EngineeringMaterials ScienceInorganic ChemistrySurface EngineeringSurface ScienceAdsorption ProcessesFuel Cell MaterialsFuel CellsSurface AdsorptionSurface PhysicsSurface ReactionsAdsorption On Oxide SurfacesAdsorptive DesulfurizationDesorptionDesorption ProcessesReversible AdsorptionSolid Oxide Fuel CellsSorbent MaterialsSpace Velocities
Sorbent materials that allow for high-temperature, regenerative desulfurization of fuel gas streams for the anode of a solid oxide fuel cell have been developed. Reversible adsorption of H2S on cerium and lanthanum oxide surfaces is demonstrated over many cycles at temperatures as high as 800 degrees C, on both fresh or presulfided sorbents, and at very high space velocities. The adsorption and desorption processes are very fast, and removal of H2S to sub-parts per million levels is achieved at very short (millisecond) contact times. Any type of sulfur-free gas, including water vapor, can be used to regenerate the sorbent surface. Preferably, the anode off-gas stream is used to sweep the desorbed H(2)S to a burner.
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