REMOVAL OF HYDROGEN-SULFIDE FROM NATURAL-GAS THROUGH AN ELECTROCHEMICAL MEMBRANE SEPARATOR

An advanced process is developed for the separation of H2S from natura l gas through an electrochemical membrane. H2S is removed from natural gas by reduction to the sulfide ion and H-2 at the cathode. The sulfi de ion migrates to the anode through a molten salt electrolyte suspend ed in an inert ceramic matrix. Once at the anode it is oxidized to ele mental sulfur and swept away for condensation in an inert gas stream. The natural gas is enriched with H-2. Order-of-magnitude reductions in H2S concentration have been repeatedly recorded on a single pass thro ugh the cell. This process allows removal of H2S, while producing H-2 and elemental sulfur directly. No absorbents are used, and there is no need for subsequent treatment of a concentrated H2S stream as with co nventional gas sweetening technology. This makes the process economica lly attractive, since it is much less equipment-intensive than convent ional technology.