US2940824A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of white calcium cyanamide
Assignee: Evonik Operations GmbH
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Filing: 1955-09-30
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Granted: 1960-06-14
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Expires: 1975-09-30
Abstract
No abstract record available.
Inventors
- 👤 Kaess Franz
- 👤 Kronacher Hermann
- 👤 Dichtl Walter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:55
CPC Classifications
C; C01; C01C; C01C3/00; C01C3/16; C01C3/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
100 words
A METHOD OF PREPARING CALCIUM CYANAMIDE COMPRISING TREATING A FINELY DIVIDED COMPOUND SELECTED FROM THE GROUP CONSISTING OF CALICUM CARBONATE AND CALCIUM OXIDE WITH A GAS SELECTED FROM THE GROUP CONSISTING OF HYDROGEN CHLORIDE AND SULFUR DIOXIDE UNTIL IT CONTAINS ABOUT 0.8 TO 1.5 PERCENT BY WEIGHT OF THE RESPECTIVE CALCIUM SALT, PLACING SAID COMPOUND IN A REACTION ZONE, AND PASSING THROUGH SAID REACTION ZONE AT A TEMPERATURE OF ABOUT 600 TO 900*C. A GAS MIXTURE CONTAINING CARBON MONOXIDE AND AMMONIA AT A RATE OF FLOW AND A PRESSURE MAINTAINING SAID COMPOUND FLOATING IN TURBULENT MOTION IN SAID REACTION ZONE.
Claim 2
Independent Claim
100 words
A METHOD OF PREPARING CALCIUM CYANAMIDE COMPRISING TREATING A FINELY DIVIDED COMPOUND SELECTED FROM THE GROUP CONSISTING OF CALICUM CARBONATE AND CALCIUM OXIDE WITH A GAS SELECTED FROM THE GROUP CONSISTING OF HYDROGEN CHLORIDE AND SULFUR DIOXIDE UNTIL IT CONTAINS ABOUT 0.8 TO 1.5 PERCENT BY WEIGHT OF THE RESPECTIVE CALCIUM SALT, PLACING SAID COMPOUND IN A REACTION ZONE, AND PASSING THROUGH SAID REACTION ZONE AT A TEMPERATURE OF ABOUT 600 TO 900*C. A GAS MIXTURE CONTAINING CARBON MONOXIDE AND AMMONIA AT A RATE OF FLOW AND A PRESSURE MAINTAINING SAID COMPOUND FLOATING IN TURBULENT MOTION IN SAID REACTION ZONE.
References Cited (Backward Citations)
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Cited
US1100539A
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US1745350A
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US2632687A
Cited
US2625464A
Cited
US2638684A
Cited
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Cited
FR1090431A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-06-14 | 1963-12-14 | 1964-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-06-14 | 1967-12-14 | 1968-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-06-14 | 1971-12-14 | 1972-06-14 | $7700.00 | Window Closed / Lapsed |