SEPARATION OF OXYGENATES FROM A HYDROCARBON STREAM

• Main Authors: DE WET, JOHAN, PETER, SCHOLTZ, JACOB, JOHANNES
• Format: Patent
• Language: English; French; German
• Published: 23.07.2003
• Edition: 7
• Subjects: CHEMISTRY; CRACKING HYDROCARBON OILS; FUELS; LUBRICANTS; METALLURGY; MINERAL WAXES; PEAT; PETROLEUM, GAS OR COKE INDUSTRIES; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVEHYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, ORGASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; TECHNICAL GASES CONTAINING CARBON MONOXIDE

This invention relates to a method for separating olefins and paraffins from oxygenates in a liquid hydrocarbon stream containing a high proportion of olefins, paraffins and oxygenates (mainly alcohols). Typically, the hydrocarbon stream is obtained from a Fischer-Tropsch process. The organic counter-solvent has a boiling point which is less than the boiling point of the most volatile alcohol in the hydrocarbon stream. A raffinate from the liquid-liquid extractor is passed to a distillation column. A bottoms product from the distillation column comprises olefins and paraffins, and the overhead product comprising solvents is recycled. An extract from the liquid-liquid extractor is sent to a stripping column, where a bottoms product containing pure alcohol is obtained. The overhead product containing counter-solvent is recycled.