Process for the utilization of refinery C4 streams

摘要

A process is disclosed for preparing a C₄ stream for feeding to an alkylation process which reacts isobutane with butene to produce isooctane. The C₄ stream is treated in a first distillation column reactor to remove dienes and mercaptans and separate out any C₅'s which might be present. The treated C₄'s are then fed to a second distillation column reactor that concurrently isomerizes 1-butene to 2-butene and splits the normal C₄'s from the iso C₄'s. The iso C₄'s are then fed to a third distillation column reactor where a portion of the isobutene is saturated to isobutane. The C₄'s from the isomerization/splitter are combined with the C₄'s from the hydrogenation unit and fed to a cold acid alkylation unit. The third distillation column may also oligomerize a portion of the isobutene to diisobutene in the upper end which is saturated in the bottom of the column to isooctane.