Patent ID: 6137023
Filing Date: 2000-10-24
Classification: C07C,Y02P,Y10S

Abstract:
A process for obtaining iosbutene having only traces of butene- 1 and butene-2 from a feed, the major portion comprising olefinic hydrocarbons containing 4 carbon atoms per molecule, including isobutene, also butene-1 and butene-2 compounds in a ratio which substantially corresponds to the thermodynamic equilibrium, said process comprising treating said feed in a distillation zone associated with at least one hydroisomerisation reaction zone, so as convert butene-1 in the hydroisomerisation zone mostly to butene-2 and so as to produce an overhead effluent from the distillation zone which is rich in isobutene and having only traces of butene-1 and butene-2, and a bottom effluent from the distillation zone which is rich in butene-2 compounds, passing of the bottom effluent to a skeletal isomerisation zone to convert butene-2 partially to isobutene, and recycling a portion of the effluent from the skeletal isomerisation zone upstream of the distillation zone.