Patent · US Expired

Process for producing a high purity caprolactam

US5459261A · kind A · utility

2Cited by
6References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 15, 1994
Grant dateOct 17, 1995
Priority date
Expiry dateAug 15, 2014

Classification

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

Abstract

A process for producing a high purity caprolactam is disclosed in which a crude caprolactam obtained by a catalytic rearrangement of cyclohexanone oxime is subjected PA1 (1) to mixing, while stirring, with at least one hydrocarbon selected from the group consisting of aliphatic hydrocarbons and alicyclic hydrocarbons to form a liquid-liquid, two-layer liquid mixture, and then crystallizing caprolactam out of the liquid mixture; PA1 (2) to mixing with both at least one hydrocarbon selected from the group consisting of aliphatic hydrocarbons and alicyclic hydrocarbons, and water to form a liquid mixture, separating the liquid mixture into a hydrocarbon layer and a water layer, and then recovering caprolactam from the water layer; or PA1 (3) to distillation in the co-presence of at least one aliphatic saturated hydrocarbon of 10 to 18 carbon atoms.

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