Patent ID: 6225515
Filing Date: 2001-05-01
Classification: C07C

Abstract:
A process for the purification of a diolefin hydrocarbon stream containing trace quantities of acetylene compounds and the cyclic regeneration of an at least partially spent selective hydrogenation catalyst which process comprises:(a) introducing said diolefin hydrocarbon stream containing trace quantities of acetylene compounds and elemental hydrogen into a selective hydrogenation zone to selectively hydrogenate at least a portion of said acetylene compounds and to produce an at least partially spent selective hydrogenation catalyst;(b) passing the resulting effluent from said selective hydrogenation zone in step (a) to a fractionation zone to produce a diolefin hydrocarbon stream having a reduced concentration of acetylene compounds;(c) contacting the at least partially spent selective hydrogenation catalyst in said selective hydrogenation zone with a polymer solvent consisting essentially of an alkane compound having from about four to about eight carbon atoms and hydrogen to reduce the polymer content of the selective hydrogenation catalyst to thereby increase hydrogenation activity;(d) passing the resulting effluent from said selective hydrogenation zone to said fractionation zone to produce a stream comprising polymer solvents and polymer compounds;(e) recycling at least a portion of said stream comprising polymer solvent and polymer compounds to provide at least a portion of said polymer solvent in step (c);(f) recovering at least another portion of said stream comprising polymer solvent and polymer compounds;(g) recovering said diolefinic hydrocarbon stream having a reduced concentration of acetylene compounds produced in step (b); and(h) introducing said diolefin hydrocarbon stream containing trace quantities of acetylene compounds and elemental hydrogen into said selective hydrogenation zone after contact with said polymer solvent and hydrogen.