Patent ID: 7981376

Claim:
An apparatus for the isomerization of feedstock containing normal butane comprising: (a) an isomerization reactor ( 106 ) adapted to isomerize normal butane to an isobutane-containing isomerate having an inlet and an outlet for isomerate; (b) a distillation column ( 116 ) having an inlet in fluid communication with the outlet of isomerization reactor ( 106 ) a lower boiling fraction outlet conduit ( 118 ) and a higher boiling fraction outlet conduit ( 122 ), said distillation column ( 116 ) being adapted to distill at least a portion of the isobutane-containing isomerate to provide a lower boiling fraction richer in isobutane than the isomerate and a higher boiling fraction richer in normal butane than the isomerate, said higher boiling fraction containing isobutane; and (c) a membrane separator ( 124 ) having a feed side inlet in fluid communication with the higher boiling fraction conduit ( 122 ), a feed side outlet in fluid communication with line ( 118 ) from the lower boiling outlet of distillation column ( 116 ), and a permeate outlet in fluid communication with the inlet of the isomerization reactor ( 106 ).