タンタル熔融塩電解について

抄録

A method of preparing pure tantalum metal by electrolysis of Ta205 dissolved in K₂TaF₇ in the presence of other alkali halides has been worked out. Graphite crucibles capable of holding 80g of fused salts in small scale experiments and 800g in large scale one have been served as the anode, and the tantalum has been deposited upon tungsten cathode suspended in the center of the crucible (Fig. 1).
In order to obtain the optimum conditions of the preparation of tantalum metal powders by electrolysis of fused salts, bath composition, current density and electrolysis temperature heve been investigated as the factors having influence upon current efficiency, bath voltage, particle size and electrodepositing state.
Optimum conditions of electrolysis have been found as follows;
Eledrolysis temperoture 750 to 850°C
Current density at the cathode 50 to 100 A/dm² Cohcehtration ot K₂TaF₇ to carrier salts 15 to 25 per cent by welght K₂TaF₇/Ta₂ O₅ ratio 2/1 to 1/1by weight
KCl/KF ratio 3/1 to 5/3 by welght