Electrochemical Reduction of Metal Oxides

Abstract

A process for selectively forming a morphology of reduced material is disclosed. The reduced material, such as titanium, is formed by a process of electrochemically reducing a metal oxide feed material, such as titania, in a solid state in an electrolytic cell containing molten chlorine-containing electrolyte in the cell. The process for selectively forming the morphology of reduced material includes sintering the reduced material and forming a morphology that is susceptible to subsequent washing of retained electrolyte in the reduced material.

1 . A process for selectively forming a morphology of reduced material formed by a process of electrochemically reducing a metal oxide feed material in a solid state in an electrolytic cell containing molten chlorine-containing electrolyte in the cell, which process includes sintering the reduced material and forming a morphology that is susceptible to subsequent washing of retained electrolyte in the reduced material. 
     
     
         2 . The process defined in  claim 1  that includes sintering the reduced material and forming a morphology that includes a continuous network of interconnected regions of chlorine-containing electrolyte. 
     
     
         3 . The process defined in  claim 1  that includes sintering the reduced material and forming a morphology that includes a two phase structure with one phase comprising grains of reduced material having minimal amounts of electrolyte within the grains and the other phase comprising a continuous network of interconnected regions containing electrolyte. 
     
     
         4 . The process defined in  claim 1  that includes sintering the reduced material in the electrolytic cell. 
     
     
         5 . The process defined in  claim 1  that includes sintering the reduced material in a separate vessel. 
     
     
         6 . The process defined in  claim 1  that further includes removing reduced material from the cell or the separate vessel and thereafter washing the reduced material. 
     
     
         7 . The process defined in  claim 1  wherein the metal oxide feed material is in one of a powder and a pellet form. 
     
     
         8 . The process defined in  claim 1  wherein the metal oxide feed material is a titanium oxide. 
     
     
         9 . The process defined in  claim 1  wherein the electrolyte is a CaCL 2 -based electrolyte containing CaO. 
     
     
         10 . A process for electrochemically reducing a metal oxide feed material in a solid state in an electrolytic cell containing molten chlorine-containing electrolyte in the cell, which process includes sintering the electrochemically reduced material and forming a morphology that is susceptible to subsequent washing of retained electrolyte in the reduced material. 
     
     
         11 . The process defined in  claim 10  wherein, in the case of a CaCL 2 -based electrolyte containing CaO, the process includes applying an electrical potential across the anode and the cathode that is above the decomposition potential of CaO and below the decomposition of CaCL 2 . 
     
     
         12 . The process defined in  claim 10  includes sintering the reduced material and forming a morphology that includes a continuous network of interconnected regions of chlorine-containing electrolyte. 
     
     
         13 . The process defined in  claim 10  that includes sintering the reduced material and forming a morphology that includes a two phase structure with one phase comprising grains of reduced material having minimal amounts of electrolyte within the grains and the other phase comprising a continuous network of interconnected regions containing electrolyte. 
     
     
         14 . The process defined in  claim 10  that includes sintering the reduced material in the electrolytic cell. 
     
     
         15 . The process defined in  claim 10  that includes sintering the reduced material in a separate vessel. 
     
     
         16 . The process defined in  claim 10  that further includes removing reduced material from the cell or the separate vessel and thereafter washing the reduced material.