Patent · US Expired

Process for depolymerizing nylon-containing waste to form caprolactam

US5932724A · kind A · utility

11Cited by
27References
6Claims
0Family size

Assignees

Inventors

Key dates

Filing dateApr 16, 1997
Grant dateAug 3, 1999
Priority date
Expiry dateApr 16, 2017

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07D201/12
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

The present invention provides an efficient process for the recovery of caprolactam from polycaprolactam-containing waste material. The present process for depolymerizing multi-component waste material comprising polycaprolactam and non-polycaprolactam components to form caprolactam comprises the step of: in the absence of added catalyst, contacting the multi-component waste material with superheated steam at a temperature of about 250.degree. C. to about 400.degree. C. and at a pressure within the range of about 1 atm to about 100 atm and substantially less than the saturated vapor pressure of water at the temperature wherein a caprolactam-containing vapor stream is formed. The formed caprolactam may then be used in the production of engineered resins and fibers.

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