Leaching metals from spent hydroprocessing catalysts with ammonium sulfate

摘要

A process for enhancing recovery of metals, especially cobalt, from spent hydroprocessing catalysts when the spent catalyst particles are first roasted at between 400 C. and 600 C. and then contacted with a first aqueous solution of ammonia and an ammonium salt to recover nickel, cobalt, molybdenum, tungsten, and vanadium. The once- leached spent hydroprocessing catalysts are again leached by contacting them with a second aqueous solution of ammonium sulfate at a pH of 1 to 4.