Patent US3779902A successfully refreshed from Google Patents.
US3779902A
Expired / Lapsed
US
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Preparation of mineral free asphaltenes
Assignee: Petro Canada Exploration Inc
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Filing: 1971-05-21
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Granted: 1973-12-18
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Expires: 1991-05-21
Abstract
Abstract Disclosed herein is an invention directed to a method of deasphalting in which a desired amount of asphalt is removed by adjusting the solvent power of the solvent-feed system to obtain a desired cotangent theta for the system. Also disclosed is the application of the cotangent theta principle to two-stage deasphalting of Athabasca bitumen.
Inventors
- 👤 D Mitchell
- 👤 J Speight
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:54
CPC Classifications
C; C10; C10C; C10C3/00; C10C3/08; C10G; C10G21/00; C10G21/003
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
95 words
The process of claim 1 in which the hydrocarbon solvents are formulated as a single solvent or solvent blend selected from the group consisting of paraffinic or isomeric hydrocarbons having from three to eight carbon atoms, saturated substituted cycloparaffins having five or more carbon atoms and saturated unsubstituted cycloparaffins having five or more carbon atoms with the concentration of the solvent or solvent blend introduced to form the system adjusted by altering the proportions of the solvent used according to the requisite Cot theta so as to yield the desired Cot theta for the system.
Claim 2
Dependent Claim
35 words
The process of claim 1 in which the feedstock is bitumen recovered from bituminous sand, which bitumen contains between about 0.5 and about 10 wt. percent asphaltenes and at least about 3 wt. percent minerals.
Claim 3
Dependent Claim
38 words
The process of claim 3 in which the feedstock also contains between about 5 and about 30 wt. percent water and in which at least about 85 percent of such water is recovered in the first asphaltene fraction.
Claim 4
Dependent Claim
76 words
A process for deasphalting a petroleum crude oil feedstock containing asphaltenes and mineral contaminants which comprises: a. contacting said petroleum crude with hydrocarbon solvent in a deasphalting zone maintained at a cot theta solubility parameter between about -0.3 and about -0.6, whereby between about 10 and about 25 wt. percent of the asphaltenes are precipitated together with about 90 to 100 wt. percent of the mineral contaminants; and b. recovering said precipitate from said deasphalting zone.
Claim 5
Dependent Claim
95 words
The process of claim 5 in which the hydrocarbon solvents are formulated as a single solvent or solvent blend selected from the group consisting of paraffinic or isomeric hydrocarbons having from three to eight carbon atoms, saturated substituted cycloparaffins having five of more carbon atoms and saturated unsubstituted cycloparaffins having five or more carbon atoms with the concentration of the solvent or solvent blend introduced to form the system adjusted by altering the proportions of the solvent used according to the requisite cot theta so as to yield the desired cot theta for the system.
Claim 6
Dependent Claim
35 words
The process of claim 5 in which the feedstock is bitumen recovered from bituminous sand, which bitumen contains between about 0.5 and about 10 wt. percent aSphaltenes and at least about 3 wt. percent minerals.
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) | 1976-12-17 | 1977-06-18 | 1977-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-17 | 1981-06-18 | 1981-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-17 | 1985-06-18 | 1985-12-18 | $7700.00 | Window Closed / Lapsed |