Process for removing hydrogen sulfide from very sour hydrocarbon gas streams using metal sulfide

A process for sweetening a sour gas stream having an exceptionally high hydrogen sulfide concentration of greater than 25 vol. % and a lower hydrocarbon concentration in the range upwardly to 75 vol. %, wherein said process comprises:

• introducing said sour gas stream into a sulfidation zone, operated under suitable sulfidation conditions and containing a lower metal sulfide, and contacting therein said gas stream with said lower metal sulfide to thereby yield molecular hydrogen and a higher metal sulfide;
• passing from said sulfidation zone a treated gas stream containing molecular hydrogen and having a reduced hydrogen sulfide concentration of less than 1 vol. % (10,000 ppmv);
• and
• passing from said sulfidation zone said higher metal sulfide and introducing it into a regeneration zone, operated under suitable regeneration conditions and containing molecular oxygen, and contacting therein said higher metal sulfide with said molecular oxygen to thereby yield lower metal sulfide and sulfur dioxide.