Separation of toluene diisocyanate from the residues of the production thereof
US4918220A · kind A · utility
5Cited by
1References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 13, 1989 |
| Grant date | Apr 17, 1990 |
| Priority date | — |
| Expiry date | Jan 13, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/54
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Toluene diisocyanate (TDI) is separated and recovered from the residues of the production thereof, e.g., from the tars of phosgenation of an aromatic diamine, by extracting such residues with an extractant which comprises an inert gas, e.g., CO.sub.2, in either the liquid or supercritical state, optionally in the presence of a coextractant diluent, for example an ester, aromatic hydrocarbon or chlorinated aromatic hydrocarbon, or chlorinated aliphatic hydrocarbon.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.