US3779896A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lube oil manufacture
Assignee: Texaco Inc
•
Filing: 1971-08-04
•
Granted: 1973-12-18
•
Expires: 1991-08-04
Abstract
Abstract Lubricating oils are prepared by subjecting a residuum containing petroleum fraction to simultaneous deasphaltingsolvent refining using a solvent, e.g., furfural or N-methyl-2pyrrolidone. The resulting raffinate is hydrocracked and then dewaxed. N-methyl-2-pyrrolidone is superior to furfural as a deasphalting-solvent refining agent because of its greater thermal stability and solvent capacity.
Inventors
- 👤 R Woodle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:37
CPC Classifications
C; C10; C10G; C10G21/00; C10G21/003; C10G2400/00; C10G2400/10
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
13 words
The process of claim 1 in which the hydrocracked lubricating oil is dewaxed.
Claim 2
Dependent Claim
14 words
The process of claim 2 in which the hydrocracked lubricating oil is catalytically dewaxed.
Claim 3
Dependent Claim
19 words
The process of claim 3 in which the dewaxing catalyst comprises a hydrogenating component supported on low sodium mordenite.
Claim 4
Dependent Claim
14 words
The process of claim 2 in which the hydrocracked lubricating oil is solvent dewaxed.
Claim 5
Dependent Claim
18 words
The process of claim 1 in which the yield of raffinate is between 40 and 60 volume percent.
Claim 6
Dependent Claim
15 words
The process of claim 1 in which the temperature is between about 730* and 800*F.
References Cited (Backward Citations)
US2121323A
Cited
GB1006508A
Cited
US3281350A
Cited
US3414506A
Cited
US3380912A
Cited
US3458432A
Cited
US3652448A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-17 | 1977-06-18 | 1977-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-17 | 1981-06-18 | 1981-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-17 | 1985-06-18 | 1985-12-18 | $7700.00 | Window Closed / Lapsed |