US2701262A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Urea purification
Assignee: Chemical Construction Corp
•
Filing: 1953-02-02
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Granted: 1955-02-01
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Expires: 1973-02-02
Abstract
No abstract record available.
Inventors
- 👤 Lucien H Cook
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:22
CPC Classifications
C; C07; C07C; C07C273/00; C07C273/02; C07C273/04; Y; Y10; Y10S; Y10S159/00; Y10S159/09
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
103 words
IN TREATING A CRUDE UREA, COMPRISING UREA, AMMONIUM CARBAMATE AND WATER, TO REMOVE THE SAID AMMONIUM CARBAMATE AS A VAPOR MIXTURE OF AMMONIA AND CARBON IDOXIDE, THE IMPROVEMENT THAT COMPRISES COCURRENTLY PASSING BOTH A FLOW OF SAID CRUDE UREA AND A FLOW OF HOT CONCENTRATED AQUEOUS SOLUTION OF SUBSTANTIALLY PURE UREA DOWNWARDLY THROUGH A PACKED VAPOR-LIQUID CONTACT ZONE, WHEREBY AMMONIUM CARBAMATE IN THE CRUDE UREA PRODUCT IS DECOMPOSED TO AMMONIA AND CARBON DIOXIDE GASES; REMOVING AMMONIA AND CARBON DIOXIDE GASES UPWARDLY FROM SAID ZONE AND REMOVING RESULTANT PURIFIED UREA PRODUCT, COMPRISING ESSENTIALLY UREA IN AQUEOUS SOLUTION, FROM THE LOWER LEVELS OF SAID ZONE.
Claim 2
Dependent Claim
103 words
IN TREATING A CRUDE UREA, COMPRISING UREA, AMMONIUM CARBAMATE AND WATER, TO REMOVE THE SAID AMMONIUM CARBAMATE AS A VAPOR MIXTURE OF AMMONIA AND CARBON IDOXIDE, THE IMPROVEMENT THAT COMPRISES COCURRENTLY PASSING BOTH A FLOW OF SAID CRUDE UREA AND A FLOW OF HOT CONCENTRATED AQUEOUS SOLUTION OF SUBSTANTIALLY PURE UREA DOWNWARDLY THROUGH A PACKED VAPOR-LIQUID CONTACT ZONE, WHEREBY AMMONIUM CARBAMATE IN THE CRUDE UREA PRODUCT IS DECOMPOSED TO AMMONIA AND CARBON DIOXIDE GASES; REMOVING AMMONIA AND CARBON DIOXIDE GASES UPWARDLY FROM SAID ZONE AND REMOVING RESULTANT PURIFIED UREA PRODUCT, COMPRISING ESSENTIALLY UREA IN AQUEOUS SOLUTION, FROM THE LOWER LEVELS OF SAID ZONE.
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) | 1958-01-31 | 1958-08-02 | 1959-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-01-31 | 1962-08-02 | 1963-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-01-31 | 1966-08-02 | 1967-02-01 | $7700.00 | Window Closed / Lapsed |