US4192731A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coal extraction process
Assignee: Sunoco Inc R&M
•
Filing: 1978-06-23
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Granted: 1980-03-11
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Expires: 1998-06-23
Abstract
Abstract Coal and other solid fossil fuels are subjected to supercritical gaseous extraction by heating a mixture of particulate coal and a solvent mixture of tetralin and xylene at supercritical temperature whereby high extractive yield is obtained and the residual solid material is easily separated from the liquid product.
Inventors
- 👤 Richard S. Stearns
- 👤 Elmer J. Hollstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:04
CPC Classifications
C; C10; C10G; C10G1/00; C10G1/04; B; B01; B01D; B01D11/00; B01D11/02; B01D11/0203; Y; Y10; Y10S; Y10S208/00; Y10S208/952
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
66 words
A process for obtaining liquids from solid fossil fuels by heating at super critical temperature in the absence of added hydrogen a mixture of particulate solid fossil fuel and a solvent mixture of from about 50% to about 75% by weight of tetralin and from about 50% to about 25% of xylene whereby said solid fuel is extracted and the solid residue retains its particulate form.
Claim 2
Dependent Claim
66 words
A process for obtaining liquids from solid fossil fuels by heating at super critical temperature in the absence of added hydrogen a mixture of particulate solid fossil fuel and a solvent mixture of from about 50% to about 75% by weight of tetralin and from about 50% to about 25% of xylene whereby said solid fuel is extracted and the solid residue retains its particulate form.
Claim 3
Dependent Claim
80 words
A process for obtaining liquids from coal by heating in the absence of added hydrogen at a supercritical temperature between about 325° C. and about 425° C. a mixture of particulate coal of from about 4 to about 30 mesh and from about 50% to about 75% by weight of tetralin and from about 50% to about 25% by weight of xylene whereby said coal is extracted to yield liquid hydrocarbon products and the solid residue retains its particulate form.
Claim 4
Dependent Claim
80 words
A process for obtaining liquids from coal by heating in the absence of added hydrogen at a supercritical temperature between about 325° C. and about 425° C. a mixture of particulate coal of from about 4 to about 30 mesh and from about 50% to about 75% by weight of tetralin and from about 50% to about 25% by weight of xylene whereby said coal is extracted to yield liquid hydrocarbon products and the solid residue retains its particulate form.
Claim 5
Dependent Claim
29 words
The process of claim 2 wherein the coal is Wyodak coal and the solvent mixture is about 75% by weight of tetralin and about 25% by weight of xylene.
Claim 6
Dependent Claim
16 words
The process of claim 3 wherein the particulate coal is between about 10 and 30 mesh.
Claim 7
Dependent Claim
13 words
The process of claim 4 wherein the reaction temperature is about 425° C.
References Cited (Backward Citations)
US3379638A
Cited
US3558468A
Cited
GB1261707A
Cited
US3966585A
Cited
US3983027A
Cited
BE835217A
Cited
BE835286A
Cited
US4039425A
Cited
US4077866A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-03-11 | 1983-09-10 | 1984-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-03-11 | 1987-09-10 | 1988-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-03-11 | 1991-09-10 | 1992-03-11 | $7700.00 | Window Closed / Lapsed |