US4112049A
Expired / Lapsed
US
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Absorption of sulfur compounds from gas streams
Assignee: Dow Chemical Co
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Filing: 1977-03-18
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Granted: 1978-09-05
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Expires: 1997-03-18
Abstract
Abstract Hydrogen sulfide and lower alkyl mercaptans are selectively extracted from a gas stream by contacting the stream with piperazinone or an alkyl substituted piperazinone which may contain a substantial proportion of water. The absorbed sulfur compounds can be regenerated by heating the extraction liquid to about 85°-150° C.
Inventors
- 👤 John W. Bozzelli
- 👤 George D. Shier
- 👤 Roscoe L. Pearce
- 👤 Charles W. Martin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 08:50
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/14; B01D53/1493
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
65 words
A process for removing sulfur compounds of the group H 2 S and lower alkyl mercaptans from a gaseous stream which comprises contacting said stream with a liquid piperazinone compound of the formula ##STR2## wherein each R, R', and R" is independently a hydrogen atom or a lower alkyl group, thereby forming a mixture of said piperazinone rich in H 2 S and alkyl mercaptans.
Claim 2
Dependent Claim
65 words
A process for removing sulfur compounds of the group H 2 S and lower alkyl mercaptans from a gaseous stream which comprises contacting said stream with a liquid piperazinone compound of the formula ##STR2## wherein each R, R', and R" is independently a hydrogen atom or a lower alkyl group, thereby forming a mixture of said piperazinone rich in H 2 S and alkyl mercaptans.
Claim 3
Dependent Claim
26 words
The process of claim 1 wherein the absorbed H 2 S and mercaptans are desorbed by heating the enriched piperazinone compound to about 85° C.-150° C.
Claim 4
Dependent Claim
11 words
The process of claim 1 wherein the piperazinone compound is 1,4-dimethylpiperazinone.
Claim 5
Dependent Claim
23 words
The process of claim 1 wherein the liquid piperazinone compound is present as its aqueous solution in about 45 to 99 percent concentration.
Claim 6
Dependent Claim
25 words
The process of claim 4 wherein the gaseous feed stream is contacted with the aqueous piperazinone compound at a temperature of about 15° C.-60° C.
Claim 7
Dependent Claim
20 words
The process of claim 4 wherein the gaseous feed stream is contacted with the aqueous piperazinone compound under superatmospheric pressure.
References Cited (Backward Citations)
GB450519A
Cited
US2649450A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-09-04 | 1982-03-06 | 1982-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-04 | 1986-03-06 | 1986-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-04 | 1990-03-06 | 1990-09-05 | $7700.00 | Window Closed / Lapsed |