US3719585A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solvent dewaxing with separation of solvent by liquid-liquid extraction
Assignee: Texaco Inc
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Filing: 1970-12-28
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Granted: 1973-03-06
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Expires: 1990-12-28
Abstract
Abstract In a dewaxing process wherein a wax-bearing mineral oil is diluted with a solvent mixture comprising an oil-solvent and a wax-antisolvent, the resultant oil-solvent mixture is cooled effecting separation of wax and the solvent mixture is separated from wax free oil by re-extraction. Re-extraction is effected by contacting the oil and solvent mixture with solvents for the waxantisolvent and for the oil-solvent. The dewaxed oil is subjected to a final brightening.
Inventors
- 👤 J Brasher
- 👤 P Bozeman
- 👤 N Odell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 07:45
CPC Classifications
C; C10; C10G; C10G73/00; C10G73/02; C10G73/06
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
168 words
In the production of a low pour test lubricating oil stock from a wax-bearing mineral oil by the steps comprising mixing said mineral oil with a solvent mixture comprising an alcohol soluble oil-solvent and a water soluble wax-antisolvent, chilling the resulting mixture to a dewaxing temperature to crystallize the wax, separating the crystallized wax from the remaining mixture comprising oil, oil-solvent, and wax-antisolvent, and recovering oil, oil-solvent and wax-antisolvent separately from said remaining mixture, the improvement which comprises: contacting said remaining with water in a first extraction zone effecting extraction of said wax-antisolvent from said remaining mixture forming a first raffinate comprising oil and said oil-solvent, contacting said first raffinate with an alcohol in a second extraction zone effecting extraction of said oil-solvent from said first raffinate forming a second raffinate comprising oil and dissolved alcohol, and contacting said second raffinate with water in a third extraction zone effecting extraction of alcohol from said second raffinate forming a third raffinate comprising said low pour test lubricating oil stock.
Claim 2
Dependent Claim
168 words
In the production of a low pour test lubricating oil stock from a wax-bearing mineral oil by the steps comprising mixing said mineral oil with a solvent mixture comprising an alcohol soluble oil-solvent and a water soluble wax-antisolvent, chilling the resulting mixture to a dewaxing temperature to crystallize the wax, separating the crystallized wax from the remaining mixture comprising oil, oil-solvent, and wax-antisolvent, and recovering oil, oil-solvent and wax-antisolvent separately from said remaining mixture, the improvement which comprises: contacting said remaining with water in a first extraction zone effecting extraction of said wax-antisolvent from said remaining mixture forming a first raffinate comprising oil and said oil-solvent, contacting said first raffinate with an alcohol in a second extraction zone effecting extraction of said oil-solvent from said first raffinate forming a second raffinate comprising oil and dissolved alcohol, and contacting said second raffinate with water in a third extraction zone effecting extraction of alcohol from said second raffinate forming a third raffinate comprising said low pour test lubricating oil stock.
Claim 3
Dependent Claim
24 words
The process of claim 1 wherein said remaining mixture is contacted with water at a temperature within the Range of about 60 to 160*F.
Claim 4
Dependent Claim
24 words
The process of claim 1 wherein said first raffinate is contacted with alcohol at a temperature within the range of about 60 to 160*F.
Claim 5
Dependent Claim
24 words
The process of claim 1 wherein said second raffinate is contacted with water at a temperature within the range of about 60 to 160*F.
Claim 6
Dependent Claim
17 words
The process of claim 1 wherein said third raffinate is brightened at a temperature of about 180*F.
Claim 7
Dependent Claim
25 words
The process of claim 1 wherein said alcohol is selected from the group consisting of methyl alcohol, ethyl alcohol, isopropyl alcohol, and normal propyl alcohol.
Claim 8
Dependent Claim
18 words
The process of claim 1 wherein said oil-solvent is selected from the group consisting of benzene and toluene.
Claim 9
Dependent Claim
26 words
The process of claim 1 wherein said wax-antisolvent is an aliphatic ketone selected from the group consisting of acetone, methyl ethyl ketone and methyl isobutyl ketone.
Claim 10
Dependent Claim
15 words
The process of claim 1 wherein said solvent mixture comprises methyl ethyl ketone and toluene.
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) | 1976-03-05 | 1976-09-04 | 1977-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-05 | 1980-09-04 | 1981-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-05 | 1984-09-04 | 1985-03-06 | $7700.00 | Window Closed / Lapsed |