US4100256A
Expired / Lapsed
US
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Hydrolysis of carbon oxysulfide
Assignee: Dow Chemical Co
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Filing: 1977-03-18
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Granted: 1978-07-11
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Expires: 1997-03-18
Abstract
Abstract The hydrolysis of carbon oxysulfide is catalyzed by piperazinone and alkyl-substituted piperazinones at ambient or below ambient temperatures. The hydrolysis step can be combined with a sour gas purification process in the treatment of refinery gases, coal gasification streams, and other such gases which contain COS and other acidic contaminants.
Inventors
- 👤 John W. Bozzelli
- 👤 Donald N. Bremer
- 👤 George D. Shier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:36
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/48; B01D53/485
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
50 words
A process for hydrolyzing COS to H 2 S and CO 2 which comprises contacting a COS-containing gas with an aqueous piperazinone compound solution, said piperazinone compound having the formula ##STR2## wherein R', R", and each R is independently a hydrogen atom or an alkyl group of 1-5 carbon atoms.
Claim 2
Dependent Claim
50 words
A process for hydrolyzing COS to H 2 S and CO 2 which comprises contacting a COS-containing gas with an aqueous piperazinone compound solution, said piperazinone compound having the formula ##STR2## wherein R', R", and each R is independently a hydrogen atom or an alkyl group of 1-5 carbon atoms.
Claim 3
Dependent Claim
23 words
The process of claim 1 wherein the piperazinone compound solution contains at least a molar equivalent quantity of water based on the COS.
Claim 4
Dependent Claim
31 words
The process of claim 2 wherein the piperazinone compound is present in an aqueous solution containing about 1-25 percent by weight of water and at least about 35 percent piperazinone compound.
Claim 5
Dependent Claim
20 words
The process of claim 3 wherein the aqueous solution also contains up to about 60 percent of a lower alkanolamine.
Claim 6
Dependent Claim
10 words
The process of claim 4 wherein the alkanolamine is diethanolamine.
Claim 7
Dependent Claim
11 words
The process of claim 3 wherein the piperazinone compound is 1,4-dimethylpiperazinone.
Claim 8
Dependent Claim
20 words
The process of claim 6 wherein the COS-containing gas is contacted with the aqueous piperazinone compound at about 10°-50° C.
Claim 9
Dependent Claim
54 words
The process of claim 6 wherein a COS-containing gas is contacted in a first process stage with the aqueous piperazinone compound solution, thereby causing the hydrolysis of at least the major part of the COS content, and the contacted gas is then contacted with a sour gas purification solvent in a second process stage.
Claim 10
Dependent Claim
19 words
The process of claim 6 wherein the COS-containing gas is contacted with the aqueous piperazinone compound under superatmospheric pressure.
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) | 1981-07-10 | 1982-01-09 | 1982-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-10 | 1986-01-09 | 1986-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-10 | 1990-01-09 | 1990-07-11 | $7700.00 | Window Closed / Lapsed |