US4255252A
Expired / Lapsed
US
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Procedure for the reprocessing of used lubricating oils
Assignee: Evonik Operations GmbH
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Filing: 1979-03-22
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Granted: 1981-03-10
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Expires: 1999-03-22
Abstract
Abstract A method for reprocessing used lubricating oils is disclosed wherein the oil is dried, treated with finely dispersed sodium metal at elevated temperature, the remaining free or organically bound metal is decomposed by means of an active hydrogen containing compounds, followed by distillation of the oil for recovery.
Inventors
- 👤 Helmut Knorre
- 👤 Manfred Langer
- 👤 Gerhard Pohl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:25
CPC Classifications
C; C10; C10M; C10M175/00; C10M175/0016
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
124 words
A process for the reprocessing of used lubricating oils by treating dried oil with finely dispersed sodium metal at an elevated temperature and subsequent separation of the treated product by distillation, the improvement consisting essentially of the oil being treated for 1 to 15 minutes at temperatures between 50° and 200° C. with 0.3 to 3.0% by weight of sodium, wherein the sodium has an average particle diameter of at most 100 μm, the remaining free and/or organically bound metal being then decomposed by means of fluid water in the amount of 0.1 to 2.0% by weight and after that the oil is distilled, said improvement eliminating the need for a preliminary purification step, mechanical removal of residual metal and an after treatment step.
Claim 2
Dependent Claim
124 words
A process for the reprocessing of used lubricating oils by treating dried oil with finely dispersed sodium metal at an elevated temperature and subsequent separation of the treated product by distillation, the improvement consisting essentially of the oil being treated for 1 to 15 minutes at temperatures between 50° and 200° C. with 0.3 to 3.0% by weight of sodium, wherein the sodium has an average particle diameter of at most 100 μm, the remaining free and/or organically bound metal being then decomposed by means of fluid water in the amount of 0.1 to 2.0% by weight and after that the oil is distilled, said improvement eliminating the need for a preliminary purification step, mechanical removal of residual metal and an after treatment step.
Claim 3
Dependent Claim
23 words
The process as in claim 1, wherein the sodium treatment is carried out for 2 to 10 minutes at 90° to 160° C.
Claim 4
Dependent Claim
19 words
The process as in claim 1 or 2, wherein from 0.5 to 2% by weight of sodium is used.
Claim 5
Dependent Claim
19 words
The process as in claim 1 or 2, wherein the sodium has an average particle diameter below 30 μm.
Claim 6
Dependent Claim
20 words
The process as in claim 1, wherein the decomposition is carried out with 0.2 to 1.0% by weight of water.
Claim 7
Dependent Claim
17 words
The process as in claim 1 or 2, wherein the distillation is carried out with stripping steam.
Claim 8
Dependent Claim
19 words
The process as in claim 1 or 2, wherein the oil is distilled of directly from the processing medium.
References Cited (Backward Citations)
US1752050A
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US1934068A
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US2722211A
Cited
US3620967A
Cited
US4097369A
Cited
US4101414A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-03-09 | 1984-09-08 | 1985-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-09 | 1988-09-08 | 1989-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-09 | 1992-09-08 | 1993-03-10 | $7700.00 | Window Closed / Lapsed |