Patent US3962410A successfully refreshed from Google Patents.
US3962410A
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Process for purifying industrial gases containing hydrogen sulfide with sulfur production
Assignee: IFP Energies nouvelles
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Filing: 1973-11-19
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Granted: 1976-06-08
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Expires: 1993-11-19
Abstract
Abstract Process for purifying industrial gases containing hydrogen sulfide and for simultaneously producing elemental sulfur, comprising contacting said gases with an aqueous solution of sodium hydroxide and/or sodium carbonate, thereby forming a sodium sulfide solution, contacting said solution with an aqueous solution of ammonium hydrogen carbonate or with a gaseous mixture of CO 2 and NH 3 so as to precipitate sodium hydrogen carbonate, decomposing the latter to CO 2 and neutral sodium carbonate which is recycled, heating the resulting liquid phase to produce NH 3 and H 2 S and producing sulfur by reacting the H 2 S with sulfurous anhydride.
Inventors
- 👤 Philippe Renault
- 👤 Andre Deschamps
- 👤 Claude Dezael
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:27
CPC Classifications
C; C01; C01B; C01B17/00; C01B17/02; C01B17/04; C01B17/05; B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/48; B01D53/52
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
116 words
A process for purifying a hydrogen sulfide containing gas by means of an aqueous solution of sodium hydroxide or sodium carbonate, comprising the steps of: a. contacting said gas with an aqueous solution of sodium hydroxide or sodium carbonate, so as to obtain a sodium sulfide solution, b. contacting the sodium sulfide solution with an aqueous solution of ammonium hydrogen carbonate or with an equivalent gaseous mixture of carbon dioxide and ammonia, to precipitate sodium hydrogen carbonate and form a remaining liquid phase. c. separating resultant precipitated sodium hydrogen carbonate from the remaining liquid phase, and d. heating the remaining liquid phase from step c), to produce a gas containing ammonia, hydrogen sulfide and carbon dioxide.
Claim 2
Dependent Claim
116 words
A process for purifying a hydrogen sulfide containing gas by means of an aqueous solution of sodium hydroxide or sodium carbonate, comprising the steps of: a. contacting said gas with an aqueous solution of sodium hydroxide or sodium carbonate, so as to obtain a sodium sulfide solution, b. contacting the sodium sulfide solution with an aqueous solution of ammonium hydrogen carbonate or with an equivalent gaseous mixture of carbon dioxide and ammonia, to precipitate sodium hydrogen carbonate and form a remaining liquid phase. c. separating resultant precipitated sodium hydrogen carbonate from the remaining liquid phase, and d. heating the remaining liquid phase from step c), to produce a gas containing ammonia, hydrogen sulfide and carbon dioxide.
Claim 3
Dependent Claim
29 words
A process according to claim 1 wherein step (a) is conducted at 50°-80°C with a sodium concentration of 0.1-4 mols per liter; and step (b) is conducted at 0°-50°C.
Claim 4
Dependent Claim
48 words
A process according to claim 1 wherein said separated sodium hydrogen carbonate is converted to carbon dioxide and sodium cabonate, the carbon dioxide is separated from the sodium carbonate, the separated carbon dioxide is recycled to step b), and the separated sodium carbonate is recycled to step a).
Claim 5
Dependent Claim
21 words
A process according to claim 3 wherein the conversion of sodium hydrogen carbonate dioxide and sodium carbonate is conducted at 120°-200°C.
Claim 6
Dependent Claim
50 words
A process according to claim 1 wherein said gas produced in step (d) containing ammonia, hydrogen sulfide and carbon dioxide is reacted with sulfur dioxide to produce sulfur, the sulfur is separated from the remaining gas containing ammonia and carbon dioxide, and said remaining gas is recycled to step (b).
Claim 7
Dependent Claim
16 words
A process according to claim 5 wherein said reacting with sulfur dioxide is conducted at 90°-170°C.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-08 | 1979-12-08 | 1980-06-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-08 | 1983-12-08 | 1984-06-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-08 | 1987-12-08 | 1988-06-08 | $7700.00 | Window Closed / Lapsed |