Patent · US Expired

Extractive distillation of C-4 hydrocarbons using modified alkoxynitrile solvent

US4269668A · kind A · utility

10Cited by
7References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 19, 1980
Grant dateMay 26, 1981
Priority date
Expiry dateMay 19, 2000

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S585/95
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

The separation of butadiene-1,3 from other C-4 hydrocarbons of lesser degree of unsaturation by extractive distillation with alkoxynitrile or aqueous alkoxynitrile as selective solvent is carried out with improved selectivity, without appreciable formation of butadiene-1,3 polymer and with consequent savings in energy by adding to the alkoxynitrile or aqueous alkoxynitrile an organic cosolvent which is dimethyl sulfoxide, sulfolane, butyrolactone, N-methyl pyrrolidone, morpholine, or trimethyl phosphate and/or an inhibitor which is 2,4-dinitrophenol or 2,4-dinitro-ortho-cresol. The organic cosolvent is present in the selective solvent composition in an amount of 5 to 30 percent by weight and the inhibitor in an amount of 0.05 to 0.6 percent by weight.

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