Patent US5675771A successfully refreshed from Google Patents.
Patent US3681230A successfully refreshed from Google Patents.
US3681230A
Expired / Lapsed
US
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Immiscible filtration of dilution chilled waxy oils
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1970-07-10
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Granted: 1972-08-01
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Expires: 1990-07-10
Abstract
Abstract IN THE DEWAXING OF HIGH VISCOSITY LUBE OILS BY DIRECT CHILLING OF THE OIL WITH A SOLVENT IN A PLURALITY OF INTENSELY AGITATED STAGES, THE SOLVENT COMPOSITION IS SO CHOSEN THAT THE OIL MISCIBLE WITH THE SOLVENT DURING MOST OF THE COOLING BUT BECOMES IMMISCIBLE NEAR THE SEPARATION TEM- PERATURE SO THAT FILTRATION OCCURS UNDER IMMISCIBLE CONDITIONS WITH IMPROVED YIELDS AND FILTER RATE.
Inventors
- 👤 John F Eagen
- 👤 John F Richards
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:28
CPC Classifications
C; C10; C10G; C10G73/00; C10G73/02; C10G73/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-01 | 1976-01-31 | 1976-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-01 | 1980-01-31 | 1980-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-01 | 1984-01-31 | 1984-08-01 | $7700.00 | Window Closed / Lapsed |