US4255248A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Two-stage coal liquefaction process with process-derived solvent having a low heptane-insolubiles content
Assignee: Chevron USA Inc
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Filing: 1979-09-07
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Granted: 1981-03-10
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Expires: 1999-09-07
Abstract
Abstract Disclosed is a two-stage process for the production of clean liquid hydrocarbons from coal. In the process subdivided coal is dissolved in a process derived solvent at a temperature in the range 425° C.-480° C. The dissolver effluent is passed through a catalytic reactor operating under hydrocracking conditions, including a temperature in the range 340° C.-400° C. to produce normally liquid products and recycle solvent. The solvent is further cooled to precipitate unconverted heptane insolubles prior to recycle to the dissolution stage.
Inventors
- 👤 Joel W. Rosenthal
- 👤 Arthur J. Dahlberg
- 👤 Christopher W. Kuehler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:05
CPC Classifications
C; C10; C10G; C10G1/00; C10G1/002
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
146 words
A process for liquefying coal which comprises: forming a coal-solvent slurry by mixing subdivided coal with a solvent; passing said slurry with added hydrogen through a dissolving zone free of externally supplied catalyst and contact particles at a temperature in the range 425°-480° C. to substantially dissolve said coal to produce a first effluent; contacting at least a portion of said first effluent from said dissolving zone in a reaction zone containing hydrocracking catalyst under hydrocracking conditions, including a temperature in the range of 340°-400° C. and a pressure in the range of 70-205 atmospheres to produce a second effluent, having a normally liquid portion containing heptane-insolubles; cooling at least a portion of said normally liquid portion of said second effluent to precipitate substantially all of said heptane-insolubles; and recycling at least a portion of the cooled, substantially heptane-insoluble-free, liquid portion for use as coal solvent.
Claim 2
Dependent Claim
146 words
A process for liquefying coal which comprises: forming a coal-solvent slurry by mixing subdivided coal with a solvent; passing said slurry with added hydrogen through a dissolving zone free of externally supplied catalyst and contact particles at a temperature in the range 425°-480° C. to substantially dissolve said coal to produce a first effluent; contacting at least a portion of said first effluent from said dissolving zone in a reaction zone containing hydrocracking catalyst under hydrocracking conditions, including a temperature in the range of 340°-400° C. and a pressure in the range of 70-205 atmospheres to produce a second effluent, having a normally liquid portion containing heptane-insolubles; cooling at least a portion of said normally liquid portion of said second effluent to precipitate substantially all of said heptane-insolubles; and recycling at least a portion of the cooled, substantially heptane-insoluble-free, liquid portion for use as coal solvent.
Claim 3
Dependent Claim
30 words
A process as recited in claim 1, wherein said portion of said normally liquid portion of said second effluent is cooled to a temperature in the range 16° C.-95° C.
Claim 4
Dependent Claim
21 words
A process as recited in claim 1, wherein said portion of said normally liquid portion is a 200° C.+ boiling fraction.
Claim 5
Dependent Claim
29 words
A process as recited in claim 1, wherein the normally liquid portion containing heptane insolubles has a heptane insolubles content in the range of 2 to 5 weight percent.
Claim 6
Dependent Claim
172 words
A process for liquefying coal which comprises: forming a coal-solvent slurry by mixing subdivided coal with a solvent; passing said slurry with added hydrogen through a dissolving zone free of externally supplied catalyst and contact particles at a temperature in the range 425° C.-480° C. to substantially dissolve said coal to produce a first effluent; contacting at least a portion of said first effluent from said dissolving zone in a reaction zone containing hydrocracking catalyst under hydrocracking conditions, including a temperature in the range of 340° C.-400° C. and a pressure in the range 70-205 atmospheres to produce a second effluent having a normally liquid portion which contains heptane-insolubles and coal residue; separating a substantial portion of the coal residue from at least a portion of said normally liquid portion of said second effluent to produce a solids-lean liquid; cooling at least a portion of said solids-lean liquid to precipitate substantially all of said heptane-insolubles; and recycling at least a portion of the cooled, substantially heptane-insoluble-free liquid for use as coal solvent.
Claim 7
Dependent Claim
172 words
A process for liquefying coal which comprises: forming a coal-solvent slurry by mixing subdivided coal with a solvent; passing said slurry with added hydrogen through a dissolving zone free of externally supplied catalyst and contact particles at a temperature in the range 425° C.-480° C. to substantially dissolve said coal to produce a first effluent; contacting at least a portion of said first effluent from said dissolving zone in a reaction zone containing hydrocracking catalyst under hydrocracking conditions, including a temperature in the range of 340° C.-400° C. and a pressure in the range 70-205 atmospheres to produce a second effluent having a normally liquid portion which contains heptane-insolubles and coal residue; separating a substantial portion of the coal residue from at least a portion of said normally liquid portion of said second effluent to produce a solids-lean liquid; cooling at least a portion of said solids-lean liquid to precipitate substantially all of said heptane-insolubles; and recycling at least a portion of the cooled, substantially heptane-insoluble-free liquid for use as coal solvent.
Claim 8
Dependent Claim
25 words
A process as recited in claim 5, wherein said portion of said solids-lean liquid is cooled to a temperature in the range 16° C.-95° C.
Claim 9
Dependent Claim
25 words
A process as recited in claim 6, wherein said portion of the normally liquid portion of said second effluent is a 200° C.+ boiling fraction.
Claim 10
Dependent Claim
29 words
A process as recited in claim 6, wherein said normally liquid portion of said second effluent has a heptane-insolubles content in the range of 2 to 5 weight percent.
References Cited (Backward Citations)
US3707461A
Cited
US3852182A
Cited
US3997425A
Cited
US4081359A
Cited
US4082643A
Cited
US4082644A
Cited
US4018663A
Cited
US4111788A
Cited
US4083769A
Cited
US4081358A
Cited
US4081360A
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 |