酸化チタン・炭素陽極を用いるマグネシウムの電解採販に関する研究 (小規模実験)

酸化物・炭素陽極の溶融塩電解への応用 (第4報)

抄録

The prebaked anode consisted of an intimate mixture of titanium dioxide and carbonaceous materials was applied in a small magnesium reduction cell containing fused mixture of magnesium chloride and sodium chloride.
The results are summarized as follows.
1) During the electrolysis, the anode consumes gradually andtitanium tetra-chloride vapour, carbon monoxide and carbon dioxide are detected in the gas exhausted from the anode room of the electrolytic cell. These facts show that free chlorine reacts onthe anode constituents as soon as it is generated by discharge of chloride ion at the anode surface.
2) The titanium tetra-chloride, which is condensed by cooling gas mixture from the anoderoom, will be used as a raw material for metallic titanium production, while magnesium obtained at the iron cathode is a suitable reducing agent to the titanium tetra-chloride. Therefore, the electrolytic extraction process of magnesium by the use of such an anode is closely connected with titanium extraction method called Kroll Process.
3) The most suitable titanium dioxide content of the anode is estimated to be 80 weight per cent at 720°C, close to the bath temperature, by considering the chlorination reaction, Ti0₂-1-(x+y) C+2Cl₂=TiCl₄+x CO₂+yCO and the Boudouard Reaction, C+CO₂⇔2CO. In our experiment, it is observed that free chlorine reacts on the anode almost perfectly, when the titanium oxide content is 50-80 weight per cent.
4) The cathodic currentefficiency was lower than that of the usual I. G. Process, but itwill be possible to raise it by improving operating conditions and the cell construction in a much larger scale electrolysis.