This Small Business Innovation Research Phase I project is an attempt to spontaneously convert the toxic gas hydrogen sulfide into useful byproducts (elemental sulfur and steam) via novel catalytic membrane technology developed at Eltron. The approach relies upon the application of proprietary mixed oxygen anion and electron conducting brownmillerite membranes and metal sulfide-based H2S decomposition catalysts which are compatible for promoting the subject reaction. These catalytic membrane reactors will possess the general configuration: H2S, AB2S4 (or MS2)/Sr2-xLaxDyFe2-yOs5+x/2/La0.8SrO.2CoO3 (or Ag), O2 (air). Tubular membrane reactor systems will be evaluated for catalytically decomposing H2S to H2 and S at 700-900 C followed by hydrogen oxidation to steam from oxygen mediated through the ceramic membrane. Preferred membrane components will then be incorporated into reactors utilizing a dispersed metal sulfide packed bed to further the decomposition of hydrogen sulfide. Work in Phase I will result in the identification of preferred components (ceramic membrane, oxidation surface catalyst, and packed bed catalyst) and optimal process operating conditions for promoting the direct conversion of H2S into elemental sulfur and steam. Successful completion of this program will result in the development of mixed oxygen anion/electron conducting membrane technology capable of efficiently promoting the direct conversion of hydrogen sulfide into elemental sulfur and water. Due to its more versatile nature and potentially lower costs, this membrane technology will find commercial application for replacing current Claus processing units for the treatment of H2S. The natural gas processing industry, petroleum refining industry, and next generation of coal-fired power plants (coal gasification) all will have an interest in this technology.
