US2916516A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Evaporation of aqueous urea solutions
Assignee: BASF SE
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Filing: 1957-01-30
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Granted: 1959-12-08
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Expires: 1977-01-30
Abstract
No abstract record available.
Inventors
- 👤 Michclitsch Walter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:50
CPC Classifications
C; C07; C07C; C07C273/00; C07C273/02; C07C273/14; C07C273/16; Y; Y10; Y10S; Y10S159/00; Y10S159/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
99 words
THE PROCESS OF EVAPORATING WATER FROM AN AQUOEUS UNREA SOLUTION CONTAINING AT LEAST ABOUT 80% OF UREA BY WEIGHT OF THE SOLUTION WITHOUT APPRECIABLE BIURET FORMATION WHICH COMPRISES AT THE SAME TIME: MAINTAINING SAID SOLUTION UNDER SUBSTAMOSPHERIC PRESSURE, HEATING SAID SOLUTION AT A TEMPERATURE IN THE RANGE OF 80*C. TO 120* C., AND INTRODUCING AMMONIA GAS INTO SAID SOLUTION, THE QUANTITY OF AMMONIA GAS INTRODUCED BEING ABOUT 5% TO 10% BY WEIGHT OF SAID SOLUTION; AND EVAPORATING WATER FROM SAID SOLUTION UNDER THE SAID CONDITIONS TO A UREA CONTENT OF ABOUT 95% TO 97, BY WEIGHT OF THE SOLUTION.
Claim 2
Dependent Claim
99 words
THE PROCESS OF EVAPORATING WATER FROM AN AQUOEUS UNREA SOLUTION CONTAINING AT LEAST ABOUT 80% OF UREA BY WEIGHT OF THE SOLUTION WITHOUT APPRECIABLE BIURET FORMATION WHICH COMPRISES AT THE SAME TIME: MAINTAINING SAID SOLUTION UNDER SUBSTAMOSPHERIC PRESSURE, HEATING SAID SOLUTION AT A TEMPERATURE IN THE RANGE OF 80*C. TO 120* C., AND INTRODUCING AMMONIA GAS INTO SAID SOLUTION, THE QUANTITY OF AMMONIA GAS INTRODUCED BEING ABOUT 5% TO 10% BY WEIGHT OF SAID SOLUTION; AND EVAPORATING WATER FROM SAID SOLUTION UNDER THE SAID CONDITIONS TO A UREA CONTENT OF ABOUT 95% TO 97, BY WEIGHT OF THE SOLUTION.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-12-07 | 1963-06-08 | 1963-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-12-07 | 1967-06-08 | 1967-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-12-07 | 1971-06-08 | 1971-12-08 | $7700.00 | Window Closed / Lapsed |