| 摘要 |
Hydrogen sulfide and/or carbon dioxide are removed from a sour gaseous stream in a contact zone by contacting the sour gaseous stream with H2S- and/or CO2- selective absorbent in an aqueous alkaline solution containing a polyvalent metal chelate at a pH of 7 to 10 wherein polyvalent metal chelate is in one embodiment of the invention in the reduced or lower valence state in a contact zone and is oxidized to the oxidized or higher valence state in an oxidation zone so as to convert hydrosulfide and/or sulfide salts present in the contact zone to sulfur. In a second embodiment, the aqueous alkaline solution and H2S- and/or CO2- selective absorbent in contact with the gaseous stream is a mixture containing a higher valence polyvalent metal chelate together with a lower valence polyvalent metal chelate, which lower valence polyvalent metal chelate is present in at least about five times the amount of the higher valence polyvalent metal chelant. |
