US4311495A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Separating carbon dioxide and ethane by liquid-liquid extraction
Assignee: Atlantic Richfield Co
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Filing: 1979-12-28
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Granted: 1982-01-19
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Expires: 1999-12-28
Abstract
Abstract A method is disclosed for separating a mixture of carbon dioxdie and ethane derived from a prior separation stage. The separation is accomplished by liquid-liquid extraction of a liquefied azeotrope of carbon dioxide and ethane with a liquid hydrocarbon having at least three carbon atoms, that is, propane, or a heavier hydrocarbon, or a mixture of hydrocarbons. The liquid-liquid extraction unit may be preceded by distillation of a carbon dioxide-ethane mixture to form the azeotrope. The ethane and extraction hydrocarbon may be separated in a subsequent distillation stage. The method is useful in carbon dioxide separation facilities where it is desirable to recover ethane that would otherwise be lost.
Inventors
- 👤 Ralph E. Styring, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:22
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/10; B; B01; B01D; B01D11/00; B01D11/04; B01D11/0488; C01; C01B; C01B32/00; C01B32/50; Y; Y02; Y02C; Y02C20/00; Y02C20/40; Y10; Y10S; Y10S62/00; Y10S62/928; Y10S62/929
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
144 words
A method for separating a mixture of carbon dioxide and ethane derived from a prior separation stage, said method comprising: (a) passing a liquid azeotrope of carbon dioxide and ethane into an extraction unit, said azeotrope having been derived from a prior carbon dioxide separation stage; (b) passing a liquid hydrocarbon comprised of at least three carbon atoms into said extraction unit in a manner and quantity such that said liquid azeotrope and said liquid hydrocarbon mix and a substantial portion of said ethane in said azeotrope is extracted with said liquid hydrocarbon; (c) removing a first fluid stream from said extraction unit, said first fluid having a greater concentration of carbon dioxide than said liquid azeotrope, and (d) removing a second fluid stream from said extraction unit, said second fluid being comprised of said hydrocarbon liquid and ethane extracted from said liquid azeotrope.
Claim 2
Independent Claim
144 words
A method for separating a mixture of carbon dioxide and ethane derived from a prior separation stage, said method comprising: (a) passing a liquid azeotrope of carbon dioxide and ethane into an extraction unit, said azeotrope having been derived from a prior carbon dioxide separation stage; (b) passing a liquid hydrocarbon comprised of at least three carbon atoms into said extraction unit in a manner and quantity such that said liquid azeotrope and said liquid hydrocarbon mix and a substantial portion of said ethane in said azeotrope is extracted with said liquid hydrocarbon; (c) removing a first fluid stream from said extraction unit, said first fluid having a greater concentration of carbon dioxide than said liquid azeotrope, and (d) removing a second fluid stream from said extraction unit, said second fluid being comprised of said hydrocarbon liquid and ethane extracted from said liquid azeotrope.
Claim 3
Dependent Claim
84 words
In the method of claim 1 wherein the method includes the following additional steps: (e) passing a fluid mixture comprised of carbon dioxide and ethane into a first distillation column to separate ethane from said mixture and to form an overhead azeotrope of carbon dioxide and ethane, said fluid mixture having been derived from a prior carbon dioxide separation stage, and (f) liquefying at least a portion of said azeotrope to form at least a portion of the liquid azeotrope used in step (a).
Claim 4
Dependent Claim
61 words
In the method of claim 2 wherein the method includes the following additional step: (g) passing at least a portion of said second fluid produced in step (d) to a second distillation column to separate at least a portion of the hydrocarbons having at least three carbon atoms to form at least a portion of the hydrocarbon used in step (b).
Claim 5
Dependent Claim
60 words
In the method of claim 1 wherein the method includes the following additional step: (e) passing at least a portion of said second fluid produced in step (d) to a distillation column to separate at least a portion of the hydrocarbons having at least three carbon atoms to form at least a portion of the hydrocarbon used in step (b).
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) | 1985-01-18 | 1985-07-20 | 1986-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-01-18 | 1989-07-20 | 1990-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-01-18 | 1993-07-20 | 1994-01-19 | $7700.00 | Window Closed / Lapsed |