US3649528A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Denitrogenation by distillation in presence of alkali metals
Assignee: ExxonMobil Technology and Engineering Co
•
Filing: 1970-03-16
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Granted: 1972-03-14
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Expires: 1990-03-16
Abstract
Abstract LUBRICATING OIL FRACTIONS ARE TREATED WITH FINELY DIVIDED DISPERSIONS OF FREE ALKALI METALS OF ONE MICRON OR LESS TO REMOVE NON-BASIC AND WEAKLY BASIC NITROGEN COMPOUNDS AND THEREBY REDUCE THE COLOR AND INCREASE THE COLOR STABILITY OF THE OIL. FINELY DIVIDED SOODIUM IS PARTICULARLY EFFECTIVE. THE PROCES IS BEST CARRIED OUT BY DISTILLING THE OIL FROM A MIXTURE OF THE OIL AND THE METAL. HYDROFINING EITHER BEFORE OR AFTER THE ALKALI METAL TREAT OR BOTH FURTHER IMPROVES THE OIL.
Inventors
- 👤 Robert Kartzmark
- 👤 John M Macdonald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:51
CPC Classifications
C; C10; C10G; C10G19/00; C10G19/073; C10G65/00; C10G65/02; C10G65/04; C10G67/00; C10G67/02
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) | 1975-03-14 | 1975-09-13 | 1976-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-14 | 1979-09-13 | 1980-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-14 | 1983-09-13 | 1984-03-14 | $7700.00 | Window Closed / Lapsed |