Patent · US Expired

Plural stage drying and purification of propylene oxide

US5354431A · kind A · utility

6Cited by
11References
21Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 23, 1993
Grant dateOct 11, 1994
Priority date
Expiry dateSep 23, 2013

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07D301/32
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

Crude propylene oxide is purified by a distillation process wherein it is (a) extractively distilled in a first column using a C.sub.2 to C.sub.6 alkylene glycol extractive distillation agent to form a first overhead fraction comprising propylene oxide, C.sub.5 -C.sub.7 hydrocarbons, methanol, water and oxygen-containing impurities, (b) wherein the first overhead fraction is separated in a plurality of intermediate distillation columns to provide an intermediate propylene oxide overhead fraction consisting essentially of propylene oxide and water, and (c) the intermediate propylene oxide overhead fraction is charged to a final distillation column using a C.sub.2 to C.sub.6 alkylene glycol extractive distillation agent to form a final overhead fraction consisting essentially of propylene oxide.

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