Patent US4298455A successfully refreshed from Google Patents.
US4298455A
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Viscosity reduction process
Assignee: Texaco Inc
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Filing: 1979-12-31
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Granted: 1981-11-03
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Expires: 1999-12-31
Abstract
Abstract The viscosity of a heavy oil such as a crude petroleum oil is reduced by subjecting the oil to a visbreaking treatment in the presence of a chain transfer agent and a free radical initiator.
Inventors
- 👤 Wann-Sheng Huang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 02:03
CPC Classifications
C; C10; C10G; C10G9/00; C10G9/007
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
76 words
A process for reducing the viscosity of a heavy hydrocarbon oil having an API gravity of less than about 15° while inhibiting polymer formation which comprises subjecting said oil to a visbreaking treatment in the presence of a halogenated hydrocarbon free radical initiator present in an amount between 0.001 and 1.0% by weight and also in the presence of a chain transfer agent present in an amount between 0.1 and 5.0% by weight of the oil.
Claim 2
Dependent Claim
76 words
A process for reducing the viscosity of a heavy hydrocarbon oil having an API gravity of less than about 15° while inhibiting polymer formation which comprises subjecting said oil to a visbreaking treatment in the presence of a halogenated hydrocarbon free radical initiator present in an amount between 0.001 and 1.0% by weight and also in the presence of a chain transfer agent present in an amount between 0.1 and 5.0% by weight of the oil.
Claim 3
Dependent Claim
14 words
The process of claim 1 in which the chain transfer agent is carbon tetrachloride.
Claim 4
Dependent Claim
14 words
The process of claim 1 in which the free radical initiator is α, α'-azo-bis-iso-butyronitrile.
Claim 5
Dependent Claim
14 words
The process of claim 1 in which the free radical initiator is a peroxide.
Claim 6
Dependent Claim
14 words
The process of claim 4 in which the free radical initiator is benzoyl peroxide.
Claim 7
Dependent Claim
21 words
The process of claim 1 in which the free-radical initiator is present in an amount between 0.01 and 0.5% by weight.
References Cited (Backward Citations)
US3030387A
Cited
US3702816A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-11-02 | 1985-05-04 | 1985-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-02 | 1989-05-04 | 1989-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-02 | 1993-05-04 | 1993-11-03 | $7700.00 | Window Closed / Lapsed |