Process for Producing Ti and Apparatus Therefor

Abstract

A process for producing Ti, comprising a reduction step of reacting TiCl 4 with Ca in a CaCl 2 -containing molten salt having the Ca dissolved therein to thereby form Ti particles, a separation step of separating the Ti particles formed in said molten salt from said molten salt and an electrolysis step of electrolyzing the molten salt so as to increase the Ca concentration, wherein the molten salt increased in Ca concentration in the electrolysis step is introduced into a regulating cell to thereby render the Ca concentration of the molten salt constant and thereafter the molten salt is used for the reduction of TiCl 4 in the reduction step. In the present invention, the Ca concentration of the molten salt to be fed to the corresponding reduction vessel can be inhibited from fluctuating and, at the same time, can maintain high concentration levels. Further, a large volume of the molten salt can be treated continuously. Therefore, the reduction reaction of TiCl 4 can be efficiently performed, and the process can be effectively utilized in the production of Ti by Ca reduction as a production process for realizing Ti production on an industrial scale.

1 . A process for producing Ti which comprises the steps of:
 forming a flow of a CaCl 2 -containing molten salt having Ca dissolved therein within a reduction vessel and feeding TiCl 4  into the flow of the molten salt to thereby react the TiCl 4  with the Ca in the molten salt to form Ti particles in said molten salt;   separating the Ti particles formed in said molten salt from said molten salt; and   electrolyzing the molten salt decreased in Ca concentration in association with formation of the Ti particles to thereby increase the Ca concentration thereof,   wherein the molten salt increased in Ca concentration through the use of a principal electrolyzer in said electrolysis step is introduced into a regulating cell having a Ca supply source and brought into contact with the relevant Ca supply source, thereby adjusting the Ca concentration of said molten salt to a constant level, and then, it is used for the reduction of TiCl 4  in the reduction step.   
   
   
       2 . The process for producing Ti as claimed in  claim 1 , wherein said Ca supply source is a molten Ca—Mg alloy. 
   
   
       3 . The process for producing Ti as claimed in  claim 2 , wherein the Ca concentration in said molten Ca—Mg alloy is increased by electrolyzing the CaCl 2 -containing molten salt in an alloy electrolyzer. 
   
   
       4 . The process for producing Ti as claimed in  claim 3 , wherein the molten salt after separation of Ti particles therein in the separation step is once fed to the alloy electrolyzer, and, after decreasing the Ca concentration in the molten salt, it is fed to the principal electrolyzer. 
   
   
       5 . The process for producing Ti as claimed in  claim 1 , wherein the regulating cell is provided with a cooling function. 
   
   
       6 . An apparatus for producing Ti which comprises:
 a reduction vessel for holding a CaCl 2 -containing molten salt having Ca dissolved therein while forming a flow of the molten salt within the vessel, and for feeding TiCl 4  into the flow of the molten salt to thereby react the Ca with the TiCl 4  fed to form Ti particles,   separation means for separating the Ti particles formed in said molten salt from the molten salt,   a principal electrolyzer which is equipped with an anode and a cathode and intended for holding the molten salt after separation of said Ti particles and electrolyzing the relevant molten salt to form Ca on the cathode side, and   a regulating cell which is provided with a Ca supply source and intended for receiving the molten salt from said principal electrolyzer and causing the same to come into contact with the Ca supply source, thereby adjusting the Ca concentration of the molten salt to a constant level, and, feeding such molten salt to said reduction vessel.   
   
   
       7 . The apparatus for producing Ti as claimed in  claim 6 , wherein the Ca supply source is a molten Ca—Mg alloy. 
   
   
       8 . The apparatus for producing Ti as claimed in  claim 7 , which is provided with an alloy electrolyzer for increasing the Ca concentration of said molten Ca—Mg alloy. 
   
   
       9 . The apparatus for producing Ti as claimed in  claim 6 , wherein said regulating cell is provided with a cooling function.