Patent · US Expired

Butadiene purification with simultaneous prefractionation and vinylacetylene rejection

US4090923A · kind A · utility

2Cited by
9References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 6, 1977
Grant dateMay 23, 1978
Priority date
Expiry dateApr 6, 1997

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C7/08
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A C.sub.4 -hydrocarbon feedstream containing butenes, butadiene, and vinylacetylene is subjected to a first extractive distillation with a selective solvent to remove butenes and a first portion of vinylacetylene as the extract; by the extraction with a minor quantity of methylethyl ketone in the selective solvent in this step, it has been found that a major portion of the vinylacetylene can be rejected, together with the butenes in the rich extract and that simultaneously the quantity of butadiene extracted could be considerably reduced; in a second extractive distillation the butadiene-rich raffinate of the first extractive distillation is further purified by extractive distillation using a mixture of sulfolane and methylethyl ketone as the solvent; after solvent stripping, the butadiene stream is finally purified in a fractionation step, wherein further vinylacetylene is removed.

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