Method for producing carbamate, method for producing isocyanate, carbamate production system, and isocyanate production system
US9321024B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 21, 2014 |
| Grant date | Apr 26, 2016 |
| Priority date | — |
| Expiry date | Oct 21, 2034 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C273/04
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A method for producing carbamate including a urea production step; a carbamate-forming step; an ammonia separation step of absorbing the gas with water in the presence of carbonate to produce a gas absorption water, and separating ammonia; an aqueous alcohol solution separation step of separating an aqueous alcohol solution from the gas absorption water; an ammonia/carbon dioxide separation step of separating carbon dioxide gas from the aqueous ammonia solution in the gas absorption water from which the aqueous alcohol solution is separated; an aqueous ammonia solution reusing step of mixing the aqueous ammonia solution and carbonate with the water to be used for production of the gas absorption water.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.