Refining of Rough Indium by Method of Reactionary Electrolysis

Electro-refining of rough indium by method of reactionary electrolysis from the chloride solutions containing InCl3 was carried out. The research of ionization of rough and modified indium anodes showed a decrease in an overvoltage of dissolution of indium when using the anodes containing bismuth. The values of the activation energy of the ionization stage of rough to 7.3 kJ / mole and the indium anodes modified by bismuth with 5- and 10-fold excess of depressor in relation to the total content of impurities, amounted to 5.6 and 3.7 kJ / mole, respectively. Results of the analysis of the refined indium by ICP-OES and ICP-MS methods showed that use of bismuth as a depressor additive allowed reducing impurity (Zn, Pb, Cd, Cu, Fe, Ni, As, Tl) level to 1.1 ppm.