US3658688A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Two-stage c{11 {0 dewaxing/deoiling process
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1969-09-19
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Granted: 1972-04-25
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Expires: 1989-09-19
Abstract
Abstract An improved process for dewaxing and deoiling a petroleum oil stock with a liquid, normally gaseous solvent in which the oil feed is chilled prior to autorefrigeration by dilution with cold recycled filtrate from the final filtration of the wax-oilsolvent mixture.
Inventors
- 👤 Frank A Biribauer
- 👤 James D Bushnell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 19:54
CPC Classifications
C; C10; C10G; C10G73/00; C10G73/02; C10G73/06
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
12 words
The process of claim 1 wherein said stagewise filtration comprises 2 stages.
Claim 2
Dependent Claim
10 words
The process of claim 1 wherein said solvent comprises propane.
Claim 3
Dependent Claim
26 words
The process of claim 1 wherein the solvent-oil wax slurry is withdrawn from said cooling zone at a temperature of from about 0* to +40* F.
Claim 4
Dependent Claim
20 words
The process of claim 1 wherein said liquid, normally gaseous, solvent is a C2 to C4 hydrocarbon or mixtures thereof.
Claim 5
Dependent Claim
10 words
The process of claim 5 wherein said solvent comprises propylene.
Claim 6
Dependent Claim
217 words
A process for dewaxing a wax-containing petroleum oil fraction and deoiling the wax thus obtained, comprising introducing said fraction into a cooling zone divided into a plurality of stages, introducing a solvent selected from the group consisting of C2-C4 hydrocarbons and mixtures thereof, into said cooling zone at a plurality of points along said cooling zone, maintaining a high degree of agitation in each of said stages so as to provide substantially instantaneous mixing of said oil and said solvent, cooling said oil as it progresses through said cooling zone at a cooling rate of from about 2* to 10* F./minute, thereby precipitating at least a portion of the wax contained in said oil and forming a solvent-oil-wax slurry, vaporizing at least a portion of said solvent from said slurry thereby precipitating a further portion of said wax, separating a dewaxed oil and an oil-containing wax from said slurry, removing at least a portion of said oil from said oil-containing wax by mixing therewith solvent thereby forming an oil-solvent mixture containing said wax, separating a deoiled wax from said mixture by stagewise filtration thereof, recovering a final stage filtrate comprising an oil-solvent mixture and recycling at least a portion of said oil-solvent mixture of said final stage filtrate to said cooling zone for use as solvent therein.
Claim 7
Dependent Claim
11 words
The process of claim 7 wherein said C2-C4 hydrocarbon comprises propylene.
Claim 8
Dependent Claim
11 words
The process of claim 7 wherein said C2-C4 hydrocarbon comprises propane.
Claim 9
Dependent Claim
25 words
The process of claim 7 wherein said solvent-oil-wax slurry is withdrawn from said cooling zone at a temperature of from about 0* to 40* F.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-25 | 1975-10-25 | 1976-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-25 | 1979-10-25 | 1980-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-25 | 1983-10-25 | 1984-04-25 | $7700.00 | Window Closed / Lapsed |