Patent · US Expired

Method for the separation of a crude C4 cut

US7557257B2 · kind B2 · utility

2Cited by
8References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 22, 2004
Grant dateJul 7, 2009
Priority date
Expiry dateAug 29, 2025

Classification

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

Abstract

A process for fractionating a crude C4 fraction comprising butanes, butenes, 1,3-butadiene and small amounts of other hydrocarbons including C4-acetylenes, by extractive distillation using a selective solvent, wherein the crude C4 fraction (1) is fed into the middle region of a first extractive distillation column (K I) and the selective solvent (2) is fed into the column at a point above that at which the crude C4 fraction (1) is introduced and a gaseous side stream (3) which comprises the C4-acetylenes together with predominantly the selective solvent and in which the concentration of the C4-acetylenes is below the spontaneous decomposition limit is taken off from the first extractive distillation column (K I) at a point below the feed point for the crude C4 fraction (1) and an overhead stream (5) comprising the components which are less soluble than the C4-acetylenes in the selective solvent is taken off from the top of the first extractive distillation column, is proposed.

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