Patent ID: 8025857

Claim:
An apparatus for the preferential conversion to 2-butene of a feed stream containing hydrogen and C4 compounds including 1-butene and 2-butene, comprising: a hydroisomerization reactor configured to contain a hydroisomerization catalyst for converting at least a portion of said 1-butene is said feed stream to 2-butene, the hydroisomerization reactor having a feed stream inlet and a reactor outlet, a first fractionation column configured to separate said hydroisomerized feed stream into a top stream comprising isobutane and isobutylene and a bottoms stream comprising 2-butene, the first fractionation column having a feed inlet, a top outlet and a bottoms outlet, a side draw near the top of said fractionation column above the feed inlet for removing a recycle stream, and a recycle inlet for combining said recycle stream with said feed stream upstream from said feed stream inlet.