SYNTHESIZING METHOD OF COBALT OXIDE FROM WASTE CEMENTED CARBIDE AND COBALT OXIDE MANUFACTURED BY THE METHOD

PURPOSE: A synthesizing method for cobalt oxide from waste hard metals and cobalt oxide manufactured by the method are provided to obtain high purity cobalt oxide having excellent dispersibility and crystalline and a particle size of 10-100 nano meters. CONSTITUTION: A synthesizing method for cobalt oxide from waste hard metals comprises the following steps: heating waste hard metals and zinc in a crucible at less than the boiling point of the zinc; volatilizing the zinc component by heating the waste hard metals and zinc at a specific temperature; pulverizing tungsten carbide-cobalt lump after cooling the crucible; acid processing the tungsten carbide-cobalt powder using phosphoric acid and removing remaining zinc(Zn); acid processing the tungsten carbide-cobalt powder using hydrochloric acid solution; dissolving cobalt (Co) in the hydrochloric acid solution; manufacturing Co(OH) by adding alkali solution to the hydrochloric acid solution until pH becomes 7-14; selectively separating Co(OH)2 by filtering and centrifuging the hydrochloric acid solution; dispersing Co(OH)2 into distilled water; adding hydrogen peroxide to the dispersed Co(OH)2; and heating the solution in which the hydrogen peroxide is added at 120-500 deg. Celsius.