US4040941A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for liquefying coal
Assignee: National Institute of Advanced Industrial Science and Technology
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Filing: 1975-11-17
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Granted: 1977-08-09
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Expires: 1995-11-17
Abstract
Abstract A process for liquefying coal to produce liquid fuel and pitch-like substances suitable as starting materials for various carbonaceous materials, which process comprises incorporating powdery coal with a heavy oil of petroleum series having a high carbon content of at least 0.9 in terms of the atomic ratio C/H in an amount of at least 50 parts by weight per 100 parts of the powdery coal, subjecting the mixture to a heat treatment conducted at 320 DEG -400 DEG C for 0.5-10 hours thereby liquefying the coal.
Inventors
- 👤 Yasuhiro Yamada
- 👤 Hidemasa Honda
- 👤 Hitoo Kakiyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:14
CPC Classifications
C; C10; C10G; C10G1/00; C10G1/04
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
96 words
A process for liquefying coal, characterized by mixing a pitch obtained by heating asphalt at a temperature of 350°-450° C. for a time of about 0.5- 3 hours and until an atomic ratio C/H of said asphalt becomes at least 0.9 with a sufficient amount of powdery coal to give a mixing ratio by weight of 2:1 to 1:10 of pitch to said powdery coal, and then heating the mixture for 0.5-10 hours at 320°-400° C. to substantially dissolve said coal in said pitch and form a substantially homogeneous mixture substantially free of undissolved coal particles.
Claim 2
Dependent Claim
96 words
A process for liquefying coal, characterized by mixing a pitch obtained by heating asphalt at a temperature of 350°-450° C. for a time of about 0.5- 3 hours and until an atomic ratio C/H of said asphalt becomes at least 0.9 with a sufficient amount of powdery coal to give a mixing ratio by weight of 2:1 to 1:10 of pitch to said powdery coal, and then heating the mixture for 0.5-10 hours at 320°-400° C. to substantially dissolve said coal in said pitch and form a substantially homogeneous mixture substantially free of undissolved coal particles.
Claim 3
Dependent Claim
12 words
A process according to claim 1 wherein said asphalt is straight asphalt.
Claim 4
Dependent Claim
13 words
A process according to claim 1 wherein said asphalt is a naphtha tar.
Claim 5
Dependent Claim
26 words
A process according to claim 1 wherein the temperature during conversion of said asphalt into said pitch is selected from a temperature range of 400°-430° C.
Claim 6
Dependent Claim
27 words
A process according to claim 1 wherein said powdery coal is mixed with said pitch in a mixing ratio of 1:1 to 1:2 to said powdery coal.
Claim 7
Dependent Claim
21 words
A process according to claim 1 wherein a mixture of said pitch and said powdery coal is heated at 360°-390° C.
Claim 8
Dependent Claim
32 words
A process according to claim 1 wherein said substantially homogeneous mixture is diluted with a sufficient amount of anthracene or creosote oil to form a fuel which is liquid at room temperature.
References Cited (Backward Citations)
US1561322A
Cited
US3642608A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-08-08 | 1981-02-07 | 1981-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-08 | 1985-02-07 | 1985-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-08 | 1989-02-07 | 1989-08-09 | $7700.00 | Window Closed / Lapsed |