Direct Electrolytic Reduction of Solid Cr₂O₃ to Cr Using SOM Process

Abstract

A novel process of solid-oxide-oxygen-ion conducting membrane (SOM) technique has been investigated to produce Cr metal directly from Cr2O3 in molten CaCl2. The sintered porous Cr2O3 pellet was employed as the cathode while liquid copper, saturated with graphite powder and encased in a one-end-closed yttria-stabilized-zirconia (YSZ) tube, acted as the anode. The particle sizes and porosity of the cathode pellets are important factors that have significant impact on the electrolysis process. The optimal experimental condition is pellet forming pressure 4MPa, sintering and electrolytic temperature 1150°C, cell voltage 3.5V, electrolysis time 2h.