Patent US2544878A successfully refreshed from Google Patents.
US2632771A
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Urea synthesis
Assignee: Phillips Petroleum Co
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Filing: 1949-11-07
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Granted: 1953-03-24
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Expires: 1969-11-07
Abstract
No abstract record available.
Inventors
- 👤 Donald H White
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:38
CPC Classifications
C; C07; C07C; C07C273/00; C07C273/02; C07C273/04; Y; Y02; Y02P; Y02P20/00; Y02P20/141
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
119 words
IN A PROCESS WHEREIN UREA IS BEING FORMED BY THE INTERACTION OF AMMONIA AND CARBON DIOXIDE AT AN ELEVATED TEMPERATURE AND PRESSURE, THE IMPROVEMENT WHICH COMPRISES MAINTAINING THE UPPER PORTION OF THE REACTION MIXTURE AT AN ELEVATED TEMPERATURE SUITABLE FOR THE SYNTHESIS REACTION, MAINTAINING THE REMAINING LOWER PORTION OF THE REACTION MIXTURE AT A TEMPERATURE BELOW THE CRYSTALLIZATION POINT OF UREA, AND DURING THE REACTION WITHDRAWING FROM SAID LOWER PORTION OF THE REACTION MIXTURE SOLID UREA, AMMONIUM CARBAMATE AND WATER, SEPARATING THE SOLID UREA FROM THE MOTHER LIQUOR, SEPARATING SAID LIQUOR INTO TWO PORTIONS ONE OF WHICH IS TREATED TO REMOVE WATER AND DIRECTLY RECYCLING THE OTHER PORTION TO THE REACTION WITHOUT DECOMPOSITION OF THE AMMONIUM CARBAMATE THEREIN CONTAINED.
Claim 2
Dependent Claim
119 words
IN A PROCESS WHEREIN UREA IS BEING FORMED BY THE INTERACTION OF AMMONIA AND CARBON DIOXIDE AT AN ELEVATED TEMPERATURE AND PRESSURE, THE IMPROVEMENT WHICH COMPRISES MAINTAINING THE UPPER PORTION OF THE REACTION MIXTURE AT AN ELEVATED TEMPERATURE SUITABLE FOR THE SYNTHESIS REACTION, MAINTAINING THE REMAINING LOWER PORTION OF THE REACTION MIXTURE AT A TEMPERATURE BELOW THE CRYSTALLIZATION POINT OF UREA, AND DURING THE REACTION WITHDRAWING FROM SAID LOWER PORTION OF THE REACTION MIXTURE SOLID UREA, AMMONIUM CARBAMATE AND WATER, SEPARATING THE SOLID UREA FROM THE MOTHER LIQUOR, SEPARATING SAID LIQUOR INTO TWO PORTIONS ONE OF WHICH IS TREATED TO REMOVE WATER AND DIRECTLY RECYCLING THE OTHER PORTION TO THE REACTION WITHOUT DECOMPOSITION OF THE AMMONIUM CARBAMATE THEREIN CONTAINED.
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) | 1956-03-23 | 1956-09-22 | 1957-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-03-23 | 1960-09-22 | 1961-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-03-23 | 1964-09-22 | 1965-03-24 | $7700.00 | Window Closed / Lapsed |