Preparation of 5N high purified indium by the method of chemical purification-electrolysis

The application of indium requires high purity indium as material. 5N high purity indium had been prepared by the method of a combination of chemically smelting and electrolysis. Smelting time was 10 min, the abstraction rate of cadmium was 80%-90% when used solution of I2-KI and glycerine to smelt indium. 4N metal indium was used as anode, high purity indium as cathode, In2(SO4)3-H2SO4 system as electrolyte, and In content is 100 g/L, pH 2-3 and current density 80-100 A/m2. The thallium was removed by smelting indium using 15% NH4Cl-glycerine solution for 20 min and tin by smelting indium using NaOH and NaNO3 for 20 min. The removed rate of tin was 60%.The product quality of indium reached national standard of 5N high purity indium.