Patent · US Expired

Purification of ethylene glycol recovered from polyester resins

US5672780A · kind A · utility

1Cited by
10References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 26, 1996
Grant dateSep 30, 1997
Priority date
Expiry dateJul 26, 2016

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C29/80
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

There is described a process for removing dimethyl terephthalate contaminants from ethylene glycol. The process comprises distilling ethylene glycol in the presence of an ester exchange catalyst to cause reaction between ethylene glycol and dimethyl terephthalate to form compounds that are less volatile than either ethylene glycol or dimethyl terephthalate, such as bishydroxyethyl terephthalate.

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