Patent ID: 8221710

Claim:
A method of recovering metals from finely divided metal sulfides, from metal sulphide ores, containing a Group VIB metal and a Group VIII metal, the method comprising the steps of: contacting the finely divided metal sulfides with a leaching solution containing ammonia and air to dissolve the Group VIB metal and the Group VIII metal into the leaching solution at a sufficient temperature and pressure to form a pressure leach slurry containing at least a Group VIB soluble metal complex and at least a Group VIII soluble metal complex and solid residue; separating and removing the solid residue from the pressure leach slurry and forming a pressure leach solution; mixing the pressure leach solution with an additive selected from the group consisting of a mineral acid, a sulfide-containing compound, and a sulphur compound under mixing conditions at a temperature in the range of 50 to 90° C. for a sufficient amount of time to precipitate at least a portion of the Group VIB metal and at least a portion of the Group VIII metal, wherein the precipitation is carried out at a first pre-selected pH to precipitate as metal complexes at least a portion of the Group VIB metal and at least a portion of the Group VIII metal.