US2744133A
Expired / Lapsed
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Process for the production of low-biuret content urea
Assignee: Inventa AG fuer Forschung und Patentverwertung
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Filing: 1953-04-24
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Granted: 1956-05-01
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Expires: 1973-04-24
Abstract
No abstract record available.
Inventors
- 👤 Cramer Charles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:27
CPC Classifications
C; C07; C07C; C07C273/00; C07C273/02; C07C273/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
127 words
IN THE PRODUCTION OF A LOW-BIURET CONTENT UREA BY SYNTHESIS FROM CO2 AND NH3 AND DECOMPOSITION OF UNCONVERTED PRIMARILY FORMED AMMONIUMCARBAMATE, THE STEPS WHICH COMPRISES CARRYING OUT SAID DECOMPOSITION IN TWO SEPARATE STAGES BY FIRST PASSING AN AQUEOUS SOLUTION CONTAINING SAID AMMONIUMCARBAMATE THROUGH A REACTION CHAMBER AT HIGHER TEMPERATURE OF ABOUT 140* C. FOR A VERY SHORT TIME OF A FRACTION OF ONE SECOND, THEREBY EFFECTING THE DECOMPOSITION OF ABOUT 90% OF AMMONIUMCARBAMATE PRESENT IN THE SOLUTION, WITH FORMATION OF ONLY 0.2-0.4% OF BIURET, SEPARATING THE GASEOUS AND LIQUID REACTION PRODUCT, AND THERAFTER MAINTAINING THE REMAINING APPROXIMATELY 10% OF CARBAMATE CONTAINED IN THE LIQUID PHASE AT LOWER TEMPERATURE OF ABOUT 78* C. FOR A PERIOD OF SEVERAL MINUTES, THUS OBTAINING A UREA WITH SAID LOW BIURET CONTENT.
Claim 2
Dependent Claim
127 words
IN THE PRODUCTION OF A LOW-BIURET CONTENT UREA BY SYNTHESIS FROM CO2 AND NH3 AND DECOMPOSITION OF UNCONVERTED PRIMARILY FORMED AMMONIUMCARBAMATE, THE STEPS WHICH COMPRISES CARRYING OUT SAID DECOMPOSITION IN TWO SEPARATE STAGES BY FIRST PASSING AN AQUEOUS SOLUTION CONTAINING SAID AMMONIUMCARBAMATE THROUGH A REACTION CHAMBER AT HIGHER TEMPERATURE OF ABOUT 140* C. FOR A VERY SHORT TIME OF A FRACTION OF ONE SECOND, THEREBY EFFECTING THE DECOMPOSITION OF ABOUT 90% OF AMMONIUMCARBAMATE PRESENT IN THE SOLUTION, WITH FORMATION OF ONLY 0.2-0.4% OF BIURET, SEPARATING THE GASEOUS AND LIQUID REACTION PRODUCT, AND THERAFTER MAINTAINING THE REMAINING APPROXIMATELY 10% OF CARBAMATE CONTAINED IN THE LIQUID PHASE AT LOWER TEMPERATURE OF ABOUT 78* C. FOR A PERIOD OF SEVERAL MINUTES, THUS OBTAINING A UREA WITH SAID LOW BIURET CONTENT.
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) | 1959-05-01 | 1959-10-31 | 1960-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-05-01 | 1963-10-31 | 1964-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-05-01 | 1967-10-31 | 1968-05-01 | $7700.00 | Window Closed / Lapsed |