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Disclosed is a process for the removal of sulfur from a fuel gas stream that additionally contains carbon dioxide and a light olefin as well as an organic sulfur compound. The process includes hydrotreating the fuel gas stream followed by a catalytic reduction of the resulting hydrotreated fuel gas

Disclosed is a process for the removal of sulfur from a fuel gas stream that additionally contains carbon dioxide and a light olefin as well as an organic sulfur compound. The process includes hydrotreating the fuel gas stream followed by a catalytic reduction of the resulting hydrotreated fuel gas to remove the carbonyl sulfide contained therein that is yielded in the hydrotreating step as a result of the equilibrium reaction of hydrogen disulfide with carbon dioxide to yield carbonyl sulfide and water.

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1. A process for removing sulfur from a fuel gas stream to a hydrogen sulfide concentration of less than 10 ppmv, said fuel gas stream comprising a carbon dioxide concentration in the range of from 1 ppmv to 3 vol %, a light olefin concentration in the range of from 0.5 vol % to 40 vol %, and an org

1. A process for removing sulfur from a fuel gas stream to a hydrogen sulfide concentration of less than 10 ppmv, said fuel gas stream comprising a carbon dioxide concentration in the range of from 1 ppmv to 3 vol %, a light olefin concentration in the range of from 0.5 vol % to 40 vol %, and an organic sulfur compound concentration in the range of from 40 ppmv to 5000 ppmv, wherein said process comprises: (a) introducing said fuel gas stream into a hydrotreater reactor containing a hydrotreating catalyst, wherein said fuel gas stream is contacted under hydrodesulfurization process conditions with said hydrotreating catalyst, wherein said hydrodesulfurization process conditions include a hydrodesulfurization contacting temperature in the range of from 230° C. to 480° C., a hydrodesulfurization contacting pressure in the range of from 30 psig to 600 psig, and a hydrodesulfurization GHSV that is in the range of from 0.01 hr−1 to 6000 hr−1, and yielding from said hydrotreater reactor a hydrotreated fuel gas containing H2S and a COS concentration in the range of from 1 ppmv to 1.5 vol %;(b) introducing said hydrotreated fuel gas into a hydrolysis reactor containing a hydrolysis catalyst, which catalyst has a total pore volume in the range of from 0.3 cc/gram to 1.5 cc/gram, and a low macroporosity, with the total pore volume in macropores having a pore diameter of greater than 750 angstroms of less than 0.2 cc/gram, wherein the hydrolysis process conditions in said hydrolysis reactor include a hydrolysis reactor inlet temperature in the range of from 75° C. to 265° C., a hydrolysis contacting pressure in the range of from 30 psig to 600 psig and a hydrolysis GHSV that is in the range of from 0.01 hr−1 to 6000 hr−1, wherein said hydrotreated fuel gas is contacted under said hydrolysis process conditions with said hydrolysis catalyst thereby converting COS to hydrogen sulfide, and yielding from said hydrolysis reactor a hydrolysis reactor effluent having a reduced COS concentration of less than 10 ppmv;(c) treating said hydrolysis reactor effluent in an absorption unit employing an amine absorbent to remove hydrogen sulfide, yielding a treated fuel gas stream having less than 10 ppmv H2S; and(d) diluting the light olefin-containing fuel gas stream in step (a) with a portion of the treated fuel gas from step (c) to help control the temperature of the hydrotreater reactor to avoid problems attributable to the olefin hydrogenation reaction. 2. A process as recited in claim 1, further comprising: prior to introducing said hydrotreated fuel gas into said hydrolysis reactor, cooling said hydrotreated fuel gas to said hydrolysis reactor inlet temperature; andproviding to said hydrotreater reactor said fuel gas stream having a hydrotreater reactor inlet temperature so as to provide said hydrodesulfurization contacting temperature. 3. A process as recited in claim 2, wherein said cooling step includes: exchanging heat energy between at least a portion of said fuel gas stream and at least a portion of said hydrotreated fuel gas by use of a first heat exchanger to thereby provide said hydrotreated fuel gas having said hydrolysis reactor inlet temperature and said fuel gas stream having said hydrotreater reactor inlet temperature. 4. A process as recited in claim 3, wherein the catalytic conversion of COS in step (b) exceeds 90 vol %. 5. A process as recited in claim 4, wherein said hydrolysis catalyst in step (b) has a surface area in the range of 150 to 400 m2/g. 6. A process as recited in claim 5, wherein said hydrolysis catalyst in step (b) has a total pore volume in the range of from 0.4 cc/gram. 7. A process as recited in claim 6, wherein the catalytic conversion of COS in step (b) exceeds 97 vol %. 8. A process as recited in claim 1, wherein said hydrolysis catalyst in step (b) comprises an alumina titania composite containing from 0.5 wt % to 99 wt % titania. 9. A process as recited in any one of claims 1 through 4, wherein the olefin concentration in the fuel gas stream into the hydrotreater reactor in step (a) is from 1 vol % to 30 vol %. 10. A process as recited in claim 8, wherein said hydrolysis catalyst is promoted with one or more promoter compounds selected from the group consisting of lithium, sodium, potassium, magnesium, calcium, lanthanum and cerium. 11. A process as recited in claim 7, wherein the catalytic conversion of COS in step (b) exceeds 99 vol %. 12. A process as recited in claim 8, wherein said hydrolysis catalyst has a total pore volume in macropores having a pore diameter of greater than 750 angstroms of less than 0.15 cc/gram. 13. A process as recited in claim 1, wherein said hydrolysis catalyst in step (b) is a supported catalyst comprising a porous refractory oxide support material and a metal component selected from the group consisting of Group VIB metal component, Group VIII metal component and mixtures thereof. 14. A process as recited in claim 13, wherein the porous refractory support material is gamma alumina, the Group VIB metal component is selected from the group consisting of molybdenum and chromium, and the Group VIII metal component is cobalt.