High temperature electrochemical polishing of H(sub 2)S from coal gasification process streams. Quarterly report, October 1--December 31, 1997

摘要

An advanced process for the separation of hydrogen sulfide from coal gasification streams through an electrochemical membrane is being perfected. H(sub 2)S is removed from a synthetic gas stream, split into hydrogen, which enriches the existing syn-gas, and sulfur, which is condensed downstream from an inert sweep gas stream. The process allows for continuous removal of H(sub 2) S without cooling the gas stream while allowing negligible pressure loss through the separator. Moreover, the process is economically attractive due to the elimination of the need for a Claus process for sulfur recovery. To this extent the project presents a novel concept for improving utilization of coal for more efficient power generation. This quarter's research focused on fabricating LiCoO(sub 2) electrodes and then utilizing them in full cell experiments at 650 C. The cathode showed inefficient porosity to allow mass transfer of the extremely dilute hydrogen sulfide to the electrolyte interface.