Continuous process for scrubbing hydrogen sulfide to produce elemental sulfur

Patent · Tue Aug 23 04:00:00 EDT 1988

OSTI ID:6486283

Chang, D; McGaugh, M C

This patent describes a continuous process for treating a gas stream containing hydrogen sulfide to produce elemental sulfur therefrom. The process consisting of: (A) introducing the gas stream into a gas-aqueous liquid contact zone maintained at a pH of about 8 to about 10, wherein the liquid comprises ammonium hydroxide, to produce an aqueous solution comprising ammonium sulfide as a major component; (b) passing the aqueudssolution to a heating zone maintained at about the boiling temperature of the aqueous solution at ambient pressure, and into which there is sparged an oxygen containing gas (C) heating the aqueous solution in the heating zone, to release ammonia and hydrogen sulfide from the aqueous solution, and to oxidize the aqueous solution comprising ammonium sulfide to form an aqueous dispersion of elemental sulfur; (D) recycling the ammonia and the hydrogen sulfide to the contact zone; and (E) separating sulfur from the aqueous dispersion and recycling the residual aqueous solution substantially free of sulfur to the contact zone; wherein ammonium hydroxide is formed in the contact zone upon contact of the ammonia with the aqueous solution.

• Assignee: Dow Chemical Co., Midland, MI
• Patent Number(s): US 4765969
• OSTI ID: 6486283
• Country of Publication: United States
• Language: English

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