Abstract - Winnick - 9321968 Each year the United States produces in excess of ten million tons of hydrogen sulfide, primarily as a by-product in the refining of fossil fuels: coal, oil, and natural gas. This toxic gas is generated in the desorption of the solvent, typically an amine or alcohol, used to purify the hydrocarbon stream. Because hydrogen sulfide has no large-scale commercial use, most of it is converted to sulfur in the Claus Process, which is and incomplete oxidation with air such that hydrogen sulfide and oxygen react to form elemental solid sulfur and water. This is an exothermic reaction which releases heat, normally captured in the form of steam. A more efficient method, which generates electricity rather than heat, is being studied in this research project. A high-temperature solid oxide fuel cell which uses hydrogen sulfide as the fuel and air as the oxidant is in development. Such a device can produce clean electrical energy and simultaneously convert highly toxic gas into a safe raw material. Solid oxide electrolytes seem tolerant to hydrogen sulfide and operate at temperatures above the boiling point of sulfur, thus eliminating the poisoning effect of condensed sulfur at the negative electrode. Preliminary experimental results have shown high electrochemical activity. The nature of the chemical and the electrochemical reactions on appropriate electrode and electrolyte materials needs to be established. These materials must withstand the corrosive nature of the reactant gases, while remaining conductive and mechanically stable. Several candidate materials will be tested for performance and stability in actual fuel cell runs and under more controlled experimental conditions.
