A process for the isomerization of a feedstream comprising C.sub.5 C.sub.6
hydrocarbons where the process involves charging hydrogen and a
feedstream comprising at least normal C.sub.5 C.sub.6 hydrocarbons into
an isomerization zone and contacting said hydrogen and feedstream with an
isomerization catalyst at isomerization conditions to increase the
branching of the feedstream hydrocarbons and produce an isomerization
effluent stream comprising at least normal pentane, normal hexane,
methylbutane, dimethylbutane, and methylpentane has been discovered.
Without passing through a stabilizer, the isomerization effluent stream
is passed to a deisohexanizer zone to generate at least a stream enriched
in methylbutane and dimethylbutanes. The stream enriched in methylbutane
and dimethylbutanes is passed to an isomerate striper column to remove
butane and lighter hydrocarbons and gasses. The remainder containing the
methylbutane and dimethylbutanes is collected for use in, for example,
gasoline blending.