Process for the production of N-vinyl-2-pyrrolidone by vinylation
US6462201B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 29, 1998 |
| Grant date | Oct 8, 2002 |
| Priority date | — |
| Expiry date | May 24, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D223/10
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A single stage process, with recirculation of reactants, is provided herein for making N-vinylpyrrolidone or N-vinyl caprolactam at a high reaction rate and selectivity and at a predetermined conversion per pass. In this process a reaction mixture is formed by saturating a non-aqueous, liquid mixture of recirculating lactam, vinyl lactam and catalyst with acetylene at low temperatures and pressures to provide a high concentration of acetylene in the liquid, pumping the saturated solution into a reactor, reacting the mixture as a single liquid phase, cooling the reaction product, withdrawing a portion of the cooled product, recirculating the rest into the reaction mixture, and continuously feeding additional lactam and catalyst therein.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.