Patent · US Expired

Preparation of caprolactam

US6677449B2 · kind B2 · utility

3Cited by
3References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 29, 2002
Grant dateJan 13, 2004
Priority date
Expiry dateOct 29, 2022

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07D201/16
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A process for the preparation of caprolactam is provided, whereina) a mixture (I) containing 6-aminocapronitrile and water is reacted in the liquid phase, in the presence of a catalyst, to give a mixture (II) containing caprolactam, ammonia, water, high-boiling components and low-boiling components,b) ammonia is then removed from the mixture (II) to give a mixture (III) containing caprolactam, water, high-boiling components and low-boiling components,c) water is then removed from the mixture (III) to give a mixture (IV) containing caprolactam, high-boiling components and low-boiling components, andd) a solid (V) containing caprolactam is then obtained from the mixture (IV) by crystallization, the proportion by weight of caprolactam in the solid (V) being greater than in the mixture (IV).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.