Patent ID: 7696120

Claim:
A method of restoring catalytic activity to a spent high activity hydroprocessing catalyst, said method comprises: providing said spent high activity hydroprocessing catalyst having a first carbon concentration exceeding about 3 weight percent, wherein said spent high activity hydroprocessing catalyst is a high activity hydroprocessing catalyst that has become spent by use in the hydrotreatment of a hydrocarbon feedstock under hydrotreatment conditions, and wherein said high activity hydroprocessing catalyst comprises a porous carrier and a catalytically active metal, wherein said high activity hydroprocessing catalyst is made by combining said porous carrier and said catalytically active metal in a manner so as to include a volatile compound; forming an uncalcined catalyst precursor having a volatile content in the range of from 0.5 wt. % to 25 wt. %; and sulfur treating said uncalcined catalyst precursor to provide said high activity hydrotreating catalyst; reducing the concentration of carbon on said spent hydroprocessing catalyst to thereby provide a carbon-reduced catalyst having a second carbon concentration in the range of from 0.5 weight percent to about 2.5 weight percent by contacting under carbon burning conditions said spent hydroprocessing catalyst with an oxygen-containing gas comprising oxygen and controlling the amount of carbon removed from said spent hydroprocessing catalyst so as to provide said carbon-reduced catalyst having said second carbon concentration; and treating said carbon-reduced catalyst with a chelating agent to thereby provide a revitalized catalyst.