Process for gently cooling and crystallizing melamine from a melamine melt or from the gaseous phase
US7153962B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 12, 2005 |
| Grant date | Dec 26, 2006 |
| Priority date | — |
| Expiry date | Jul 12, 2025 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D251/62
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Process for cooling and crystallizing solid melamine from the gaseous phase or from melamine melts as they develop in technical processes used to produce melamine, characterized in that the melamine-containing process gases or melamine melts are introduced into liquid, organic phase at high pressure, said phase comprising polyvalent alcohols such as ethylene glycol, glycerine or their homologous series or of amines such as ethanol amines or a mixture of both groups. The advantage this process is that the hot melamine is cooled very quickly without forming thermal decomposition products and that during quenching no reaction of the melamine with the solvent occurs, the formation of higher deammoniation products such as melam and melem is prevented and higher deammoniation products of the melamine such as melam and melem, are partially converted back into melamine.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.