Patent · US Expired

Method for removal of dimethyl ether and methanol from C.sub.4 hydrocarbon streams

US5122236A · kind A · utility

16Cited by
18References
16Claims
0Family size

Inventors

Key dates

Filing dateMay 21, 1990
Grant dateJun 16, 1992
Priority date
Expiry dateMay 21, 2010

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C7/04
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A process for removing dimethyl ether (DME) and methanol impurities from C.sub.4 hydrocarbon stream without substantial loss of C.sub.4 hydrocarbons by fractionating a C.sub.4 hydrocarbon stream containing DME and methanol at low levels, e.g., less than 5 wt. % to produce an overhead of about 20 to 40 volume % of the C.sub.4 stream, condensing the overhead, contacting the condensed overhead with about 1 to 5 volumes of water, thereby removing a portion of the DME and methanol from the C.sub.4 stream, returning substantially all of the C.sub.4 stream, except the small amount solubilized in the water, to the fractionation and flashing the solubilized DME and hydrocarbons from the water. The fractionation and extraction are preferably carried out at elevated pressures, e.g., 200 to 300 psig to avoid refrigeration of the overhead condensation. The flashing of the DME and hydrocarbons is carried out by reducing the pressure on the water, e.g. atmospheric pressure at a temperature in the range of 20.degree. C. to 50.degree. C., leaving methanol in the water. The methanol can be removed by distillation or by contacting the methanol containing water stream with a large volume of a C.sub.4 …

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