US2807574A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Treatment of unreacted ammonia in the manufacture of urea
Assignee: Individual
•
Filing: 1953-10-21
•
Granted: 1957-09-24
•
Expires: 1973-10-21
Abstract
No abstract record available.
Inventors
- 👤 Hirano Masao
- 👤 Tsunoda Makoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:32
CPC Classifications
C; C01; C01C; C01C1/00; C01C1/02; C01C1/12; C07; C07C; C07C273/00; C07C273/02; C07C273/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
130 words
IN THE RECOVERY OF SUBSTANTIALLY CARBON-DIOXIDE-FREE AMMONIA FROM AQUEOUS SOLUTIONS CONTAINING AMMONIA AND CARBON DIOXIDE IN MOL RATIOS GREATER THAN UNITY, THE IMPROVED PROCESS WHICH COMPRISES: AT A PRESSURE OF FROM ABOUT 10 TO ABOUT 30 ATMOSPHERES, HEATING A MASS OF SAID SOLUTION SUFFICIENTLY TO OBTAIN AN OFF GAS MIXTURE COMPRISING ESSENTIALLY AMMONIA AND CARBON DIOXIDE; COLLECTING SAID OFF-GAS MIXTURE; AND IN A SEPARATE VESSEL PASSING COLLECTED OFF-GASES INTO A BODY OF LIQUID AMMONIA MAINTAINED UNDER A PRESSURE OF FROM ABOUT 10 TO ABOUT 30 ATMOSPHERES, CONVERTING THE CARBON DIOXIDE BY SAID STEP INTO SMALL DISCRETE PARTICLES OF AMMONIUM CARBAMATE SUSPENDED IN SAID LIQUID AMMONIA, LIBERATING CARBON DIOXIDEFREE AMMONIA GAS FROM SAID BODY OF LIQUID AMMONIA IN GREATER VOLUME THAN IS PASSED INTO SAID BODY, AND RECOVERING SO-OBTAINED AMMONIA GAS.
Claim 2
Dependent Claim
130 words
IN THE RECOVERY OF SUBSTANTIALLY CARBON-DIOXIDE-FREE AMMONIA FROM AQUEOUS SOLUTIONS CONTAINING AMMONIA AND CARBON DIOXIDE IN MOL RATIOS GREATER THAN UNITY, THE IMPROVED PROCESS WHICH COMPRISES: AT A PRESSURE OF FROM ABOUT 10 TO ABOUT 30 ATMOSPHERES, HEATING A MASS OF SAID SOLUTION SUFFICIENTLY TO OBTAIN AN OFF GAS MIXTURE COMPRISING ESSENTIALLY AMMONIA AND CARBON DIOXIDE; COLLECTING SAID OFF-GAS MIXTURE; AND IN A SEPARATE VESSEL PASSING COLLECTED OFF-GASES INTO A BODY OF LIQUID AMMONIA MAINTAINED UNDER A PRESSURE OF FROM ABOUT 10 TO ABOUT 30 ATMOSPHERES, CONVERTING THE CARBON DIOXIDE BY SAID STEP INTO SMALL DISCRETE PARTICLES OF AMMONIUM CARBAMATE SUSPENDED IN SAID LIQUID AMMONIA, LIBERATING CARBON DIOXIDEFREE AMMONIA GAS FROM SAID BODY OF LIQUID AMMONIA IN GREATER VOLUME THAN IS PASSED INTO SAID BODY, AND RECOVERING SO-OBTAINED AMMONIA GAS.
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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) | 1960-09-23 | 1961-03-25 | 1961-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-09-23 | 1965-03-25 | 1965-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-09-23 | 1969-03-25 | 1969-09-24 | $7700.00 | Window Closed / Lapsed |