To resolve the problem of low current efficiency and low reaction rate when preparing metal by electro-deoxidization method,various contents of CaO and CaCO3 were added into the TiO2 powder,which were compacted into pellets and sintered,and then conducted as the cathode. The morphology and contents of the cathode and products were studied by scanning electron microscopy and X-ray diffractometry,the effect of the additives were studied. The results show that formation of calcium titanate and change of microstructure within the cathode enhance the velocity of the direct electrochemical reduction of solid TiO2 to Ti.
Metal zirconium was prepared by electro-deoxidization method. Using CaCl2 molten salt as electrolyte,sintered ZrO2 pallets as cathode,graphite rod as anode,the pallets were electrolyzed at 900 ℃ and 3.1 V for 8,10 and 12 h,respectively. The mechanism of electro-deoxidization of ZrO2 was studied preliminarily. The results show that the morphologies of cathode pallets affect the forming process of products. The process of electro-deoxidization of ZrO2 in the molten salt is conducted step by step,from exterior of cathode to its interior and from high valence oxide to low valence oxide until to metal.
