Abstract
A method of preparing pure thorium metal by electrolysis of ThF4 in molten NaCl-KCl bath has been worked out. Graphite crucibles with a capacity of 300g salt have been used as the anode and tungsten or graphite rods as the cathode.
Care has been taken especially to the losses of thorium in the bath as related to thetemperature. Temperatures around 700°C have been found preferablein order to get a sufficient fluidity, of the bath without incurring much vaporization losses of thorium halide.
Optimum conditions of electrolysis have beenfound as follows:
Current density at the anode 0.5 to 1.0A/dm2
Current density at the cathode 20A/dm2
Concentration of ThF4 5 to 35 per cent by weight
The thorium metal is deposited as a crystalline powder in the salt matrix and is very easy to be washed and recoverd bythe aqueous technique.
