Patent US3642431A successfully refreshed from Google Patents.
US3642431A
Expired / Lapsed
US
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Method of removing hydrogen sulfide from gaseous mixtures
Assignee: Chevron USA Inc
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Filing: 1969-09-19
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Granted: 1972-02-15
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Expires: 1989-09-19
Abstract
Abstract The process for selectively removing H2S and like sulfides from fluids containing them by contact with a substantially hydroxylfree solvent such as N-methyl-2-pyrrolidone, a dicarboxylic acid anhydride soluble in said solvent and an alkali hydrosulfide. Preferably, in the process an admixture of H2S and CO2 in natural gas is contacted with the contacting solution to react the H2S with said anhydride, the CO2 and/or like hydrocarbons are rejected from the contacting solution by mild heating and/or pressure reduction and thereafter H2S is regenerated by heating the remaining solution.
Inventors
- 👤 Shigeto Suzuki
- 👤 Karl H Kilgren
- 👤 Giok H Tjoa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 14:05
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/48; B01D53/52; B01D53/526; C; C07; C07C; C07C7/00; C07C7/148; C07C7/14875
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
11 words
The process of claim 1 wherein said solvent is a pyrrolidone.
Claim 2
Dependent Claim
23 words
The process of claim 1 wherein said solvent is N-methyl-2-pyrrolidone and said contacting is carried out at a temperature below about 250* F.
Claim 3
Dependent Claim
13 words
The process of claim 1 wherein said anhydride is an alkenyl succinic anhydride.
Claim 4
Dependent Claim
13 words
The process of claim 1 wherein said anhydride is an alkylated succinic anhydride.
Claim 5
Dependent Claim
12 words
The process of claim 1 wherein said anhydride is a phthalic anhydride.
Claim 6
Dependent Claim
21 words
The process of claim 1 wherein solvent initially contains a compound capable of producing an alkali Hydrosulfide under the reaction conditions.
Claim 7
Dependent Claim
12 words
The process of claim 1 wherein said alkali hydrosulfide is potassium hydrosulfide.
Claim 8
Dependent Claim
19 words
The process of claim 1 wherein said dicarboxylic acid anhydride is free from olefinic groups in the anhydride ring.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-02-14 | 1975-08-16 | 1976-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-14 | 1979-08-16 | 1980-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-14 | 1983-08-16 | 1984-02-15 | $7700.00 | Window Closed / Lapsed |