Substantial sources of hydrogen sulfide exist with, for example natural gas, and as a product of petroleum refining - a product of the desulfurization process. Hydrogen sulfide is a poison and a corrosive agent. Converting it electrochemically to pure sulfur could produce a desirable product as well as energy. This project involves the study of the electrochemistry of hydrogen sulfide oxidation at different electrodes in a high temperature fuel cell. The process is designed to overcome the corrosive nature of hydrogen sulfide by using a solid - oxide fuel cell and the insulating nature of elemental sulfur by operating at high enough temperatures. Solid oxide fuel cells can be used for chemical synthesis as well as power production where the anode is used for selective partial oxidation of gaseous reactants. A series of oxidation catalysts will be tried: platinum applied by chemical vapor deposition or sputtering, perovskite-structure ceramics applied as a thin paste and thiospinels. Of special interest is whether the oxidation can be halted at water and elemental sulfur, or whether it proceeds to sulfur dioxide. Operating conditions, as well as electrode material, will be varied to elicit such control.
