Patent US3857686A successfully refreshed from Google Patents.
US3857686A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Glycol-butyrolactone mixtures
Assignee: Dow Chemical Co
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Filing: 1971-02-08
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Granted: 1974-12-31
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Expires: 1991-02-08
Abstract
Abstract The low temperature viscosity, freeze point depression and hydrocarbon hydrate formation depression characteristics of glycols are improved by replacing some of the glycol with butyrolactone. The mixture finds utility as a heat transfer medium and in natural gas processing.
Inventors
- 👤 J Arnold
- 👤 R Pearce
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:37
CPC Classifications
C; C10; C10G; C10G5/00; C10G5/06; C09; C09K; C09K5/00; C09K5/20
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
63 words
IN THE PROCESS OF COOLING NATURAL GAS TO REMOVE THE CONDENSIBLE FRACTION WHEREIN A HYDRATE INHIBITOR IS UTILIZED, THE IMPROVEMENT OF UTILIZING AS SAID INHIBITOR A MIXTURE CONSISTING ESSENTIALLY OF AT LEAST ONE GLYCOL SELECTED FROM THE GROUP OF ETHYLENE GLYCOL, DIETHYLENE GLYCOL, PROPYLENE GLYCOL, DIPROPYLENE GLYCOL, TRIETHYLENE GLYCOL AND TETRAETHYLENE GLYCOL AND BUTYROLACTONE IN A WEIGHT RATIO OF 95:5 TO 5:95, RESPECTIVELY.
Claim 2
Dependent Claim
63 words
IN THE PROCESS OF COOLING NATURAL GAS TO REMOVE THE CONDENSIBLE FRACTION WHEREIN A HYDRATE INHIBITOR IS UTILIZED, THE IMPROVEMENT OF UTILIZING AS SAID INHIBITOR A MIXTURE CONSISTING ESSENTIALLY OF AT LEAST ONE GLYCOL SELECTED FROM THE GROUP OF ETHYLENE GLYCOL, DIETHYLENE GLYCOL, PROPYLENE GLYCOL, DIPROPYLENE GLYCOL, TRIETHYLENE GLYCOL AND TETRAETHYLENE GLYCOL AND BUTYROLACTONE IN A WEIGHT RATIO OF 95:5 TO 5:95, RESPECTIVELY.
Claim 3
Dependent Claim
24 words
The process of claim 1 wherein said inhibitor contains one or more glycols and butyrolactone in a weight ratio of 85:15 to 65: 35.
Claim 4
Dependent Claim
15 words
The process of claim 2 wherein said inhibitor additionally contains up to about 40% H2O.
Claim 5
Dependent Claim
11 words
The process of claim 2 wherein said ratio is about 70:30.
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) | 1977-12-30 | 1978-07-01 | 1978-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-30 | 1982-07-01 | 1982-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-30 | 1986-07-01 | 1986-12-31 | $7700.00 | Window Closed / Lapsed |