Regeneration of catalyst comprising flushing with inert gas followed by

Abstract

A process for regenerating a spent hydrogenation catalyst, comprising the steps of providing a catalyst comprising a support material selected from the group consisting of an inorganic oxide-zeolite composite, carbon and zeolite, and a catalytically active metal phase selected from the group consisting of partially reduced group IB metals and completely reduced group VIII metals, said metal phase being present in an amount of grater than or equal to about 0.03 wt %, and said catalyst having an initial diolefin hydrogenation activity, treating a hydrocarbon feedstock having a diolefin content of greater than or equal to about 0.1% and a nitrite content of greater than or equal to about 2 ppm with said catalyst until said initial diolefin hydrogenation activity of said catalyst decreases to a reduced diolefin hydrogenation activity, flushing said catalyst with an inert gas so as to remove traces of hydrocarbon from said catalyst and thereby provide a flushed catalyst, and regenerating said flushed catalyst by further flushing said flushed catalyst with hydrogen so as to provide a regenerated catalyst having a regenerated diolefin hydrogenation activity which is greater than said reduced diolefin hydrogenation activity.