GB690594A - Improvements in the production of urea - Google Patents
Improvements in the production of ureaInfo
- Publication number
- GB690594A GB690594A GB7674/51A GB767451A GB690594A GB 690594 A GB690594 A GB 690594A GB 7674/51 A GB7674/51 A GB 7674/51A GB 767451 A GB767451 A GB 767451A GB 690594 A GB690594 A GB 690594A
- Authority
- GB
- United Kingdom
- Prior art keywords
- urea
- solution
- biuret
- solid
- per cent
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C273/00—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups
- C07C273/02—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of urea, its salts, complexes or addition compounds
- C07C273/14—Separation; Purification; Stabilisation; Use of additives
- C07C273/16—Separation; Purification
Abstract
Crystalline urea is obtained by washing solid urea containing biuret with an aqueous saturated solution of urea thereby substantially reducing the biuret impurity. The solid urea treated may be that obtained by reacting ammonia with carbon dioxide at elevated temperature and pressure and either concentrating the resultant urea solution to a melt which is solidified by being sprayed by means of an air current or centrifuged or cooling the urea solution to cause crystallization of the urea. The mashing may be effected by mixing the solid urea with the urea solution, by spraying the solution over a layer of the urea or by leading the solid urea and urea solution through a mixing spiral. The extractant is preferably urea solution containing only a small amount of biuret, e.g. less than 1 per cent, withdrawn from the high pressure reactor in the urea synthesis, and diluted to give a saturated solution at room temperature. With such a solution, the biuret content of the solid urea may be reduced to 0.1 to 0.2 per cent, while a further washing with biuret-free urea solution reduces the impurity to below 0.01 per cent. Examples are given.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE690594X | 1950-04-06 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB690594A true GB690594A (en) | 1953-04-22 |
Family
ID=6599813
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB7674/51A Expired GB690594A (en) | 1950-04-06 | 1951-04-03 | Improvements in the production of urea |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB690594A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CZ305573B6 (en) * | 2011-11-23 | 2015-12-16 | Farid Alekovich Batullin | Process for preparing extremely pure crystalline carbamide |
-
1951
- 1951-04-03 GB GB7674/51A patent/GB690594A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CZ305573B6 (en) * | 2011-11-23 | 2015-12-16 | Farid Alekovich Batullin | Process for preparing extremely pure crystalline carbamide |
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