US3816528A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Urea synthesis process
Assignee: Chemical Construction Corp
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Filing: 1970-11-16
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Granted: 1974-06-11
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Expires: 1990-11-16
Abstract
Abstract A UREA SYNTHESIS PROCESS EMPLOYING AMMONIA AND CARBON DIOXIDE AS FEED REACTANTS, IN WHICH MIXED OFF-GAS DERIVED FROM AMMONIUM CARBAMATE DECOMPOSITION IS COMPRESSED TOGETHER WITH FEED CARBON DIOXIDE TO UREA SYNTHESIS PRESSURE AND REACTED EXOTHERMICALLY WITH FEED AMMONIA WHILE IN HEAT EXCHANGE WITH UREA SYNTHESIS EFFLUENT STREAM, WHICH IS CONCOMITANTLY STRIPPED WITH INTERMEDIATE PRESSURE RECYCLE MIXED GAS.
Inventors
- 👤 L Cook
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:13
CPC Classifications
C; C07; C07C; C07C273/00; C07C273/02; C07C273/04; Y; Y02; Y02P; Y02P20/00; Y02P20/141
Claims Analysis
Total Claims: 0
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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) | 1977-06-10 | 1977-12-10 | 1978-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-10 | 1981-12-10 | 1982-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-10 | 1985-12-10 | 1986-06-11 | $7700.00 | Window Closed / Lapsed |