Gallium extraction from Bayer Liquor is carried out by adapting techniques
like (i) Amalgam metallurgy, (ii) Cementation with AI-Ga alloy as cementing
agent, (iii) Solvent extraction and (iv) Ion-exchange resin process. The m
etal obtained by any of the above process has a purity of about 97-99.9%. T
here are several methods of subsequent purification employed to get electro
nic grade metal (6N purity). The method presented here is simple and less c
umbersome, consisting of acid anti alkali leaching followed by anodic clean
ing ii; HCl medium, multiple shaking of the resultant gallium metal using s
aturated KCI solution containing oxidising agent like H2O2 or (NH4)(2) S2O8
and acetic acid and finally subjecting it to differential solidification.
The reported methods viz. electrorefining, vacuum heating/distillation, zon
e refining, etc could be avoided. Metal of the required 99.9999% purity is
obtained which naturally commands higher prices than lower grades.