US2808369A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coal purification
Assignee: GREAT LAKES CARBON Corp
•
Filing: 1952-11-06
•
Granted: 1957-10-01
•
Expires: 1972-11-06
Abstract
No abstract record available.
Inventors
- 👤 John H Hickey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:46
CPC Classifications
C; C10; C10L; C10L9/00; C10L9/02; C01; C01B; C01B32/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
121 words
A PROCESS FOR PURIFYING HIGH VOLATILE BITUMINOUS COAL CONTAINING SILICON IMPURITIES WHICH COMPRISES PREHEATING A COMMINUTED COAL TO A TEMPERATURE OF AT LEAST ABOUT 250* C. BUT IN ANY EVENT LESS THAN THE COKING TEMPERATURE TO EFFECT A PARTIAL DEVOLATILIZATION, CONTACTING THE PREHEATED COAL WITH A SUBSTANCE SELECT FROM THE GROUP CONSISTING OF VOLATILIZABLE FLUCRIDES OTHER THAN SILCON FLUORIDE AND HYDROGEN FLOURIDE, AT A TEMPERATURE ABOVE 100* C. AND IN ANY EVENT ABOUT THE VAPORIZATION POINT OF SAID FLUORIDE BUT BELOW THE TEMPERATURE AT WHICH THE PREHEATED COAL BECOMES PLASTIC, THEREBY REACTING THE FLOURIDE WITH THE SILICON IMPURITIES, AND FINALLY REMOVING THE RESULTING SILCON FLOURIDE AND UNREACTED FLOURIDE BY VOLATILIZATION AT A TEMPERATURE BELOW THAT AT WHICH THE PREHEATED BECOMES PLASTIC.
Claim 2
Dependent Claim
121 words
A PROCESS FOR PURIFYING HIGH VOLATILE BITUMINOUS COAL CONTAINING SILICON IMPURITIES WHICH COMPRISES PREHEATING A COMMINUTED COAL TO A TEMPERATURE OF AT LEAST ABOUT 250* C. BUT IN ANY EVENT LESS THAN THE COKING TEMPERATURE TO EFFECT A PARTIAL DEVOLATILIZATION, CONTACTING THE PREHEATED COAL WITH A SUBSTANCE SELECT FROM THE GROUP CONSISTING OF VOLATILIZABLE FLUCRIDES OTHER THAN SILCON FLUORIDE AND HYDROGEN FLOURIDE, AT A TEMPERATURE ABOVE 100* C. AND IN ANY EVENT ABOUT THE VAPORIZATION POINT OF SAID FLUORIDE BUT BELOW THE TEMPERATURE AT WHICH THE PREHEATED COAL BECOMES PLASTIC, THEREBY REACTING THE FLOURIDE WITH THE SILICON IMPURITIES, AND FINALLY REMOVING THE RESULTING SILCON FLOURIDE AND UNREACTED FLOURIDE BY VOLATILIZATION AT A TEMPERATURE BELOW THAT AT WHICH THE PREHEATED BECOMES PLASTIC.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-09-30 | 1961-04-01 | 1961-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-09-30 | 1965-04-01 | 1965-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-09-30 | 1969-04-01 | 1969-10-01 | $7700.00 | Window Closed / Lapsed |