Isomerization of a feedstream comprising C.sub.5 to C.sub.6 hydrocarbons involving charging hydrogen and the feedstream into an isomerization zone to contact an isomerization catalyst at isomerization conditions and increase the branching of the feedstream hydrocarbons to produce an isomerization effluent stream has been discovered. Without passing through a stabilizer, the isomerization effluent is passed through a product separator and a flash drum and then to an adsorptive separation zone to generate a raffinate stream enriched in branched alkanes, an extract stream enriched in normal alkanes, and at least one light ends stream. Within the adsorptive separation zone, the raffinate and the extract streams are each passed through a fractionator remove light ends and desorbent. The desorbent is recycled to the adsorptive separation zone. The remainder of the extract stream is recycled to the isomerization zone and the remainder of the raffinate stream is collected.