US3801342A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of lignite binder pitch
Assignee: United States Department of the Interior
•
Filing: 1970-11-16
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Granted: 1974-04-02
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Expires: 1990-11-16
Abstract
Abstract Binder pitch suitable for metallurgical electrode production is prepared from crude pitch obtained from the low-temperature carbonization of lignite. Aliphatic hydrocarbons contained in the crude pitch are removed by solvent extraction prior to thermal treatment such as delayed coking or thermal cracking. Binder pitch product is recovered as a residual fraction of the oil produced in the thermal treatment.
Inventors
- 👤 J Berber
- 👤 R Rice
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:06
CPC Classifications
C; C10; C10L; C10L5/00; C10L5/02; C10L5/06; C10L5/10; C10L5/14; C10L5/16; C04; C04B; C04B35/00; C04B35/515; C04B35/52; C04B35/528; C04B35/532; C10C; C10C3/00; C10C3/002
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
26 words
The process of claim 1 wherein more than 75 percent of the aliphatic hydrocarbons contained in said crude pitch are removed in the solvent extraction step.
Claim 2
Dependent Claim
26 words
The process of claim 2 wherein rich solvent from the extraction step is distilled to recover an aliphatic hydrocarbon product stream and a recycle solvent stream.
Claim 3
Dependent Claim
18 words
The process of claim 3 wherein the solvent is a branched chain aliphatic hydrocarbon having 8 carbon atoms.
Claim 4
Dependent Claim
10 words
The process of claim 4 wherein the solvent is trimethylpentane.
Claim 5
Dependent Claim
21 words
The process of claim 3 wherein said pitch binder product is mixed with particulate coke and is formed into an electrode.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-01 | 1977-10-01 | 1978-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-01 | 1981-10-01 | 1982-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-01 | 1985-10-01 | 1986-04-02 | $7700.00 | Window Closed / Lapsed |