To separately and efficiently recover Sb and Bi in the method for purifying a copper electrolyte using a chelating resin by bringing the electrolyte into contact with metallic copper to reduce Fe3+ and changing the sulfuric acid concn. in the eluant.
A waste copper electrolyte is passed through a column packed with a copper sheet to reduce Fe3+ to Fe2+ and then brought into contact with a chelating resin packed in a column to adsorb the Sb and Bi in the electrolyte. The chelating resin is then worked with hot water, a Bi eluant contg. 20-30g/l sulfuric acid and 120-180g/l NaCl and kept at 40-60°C is brought into contact with the washed chelating resin to elute Bi, and a Bi eluate is obtained. An Sb eluant contg. 100-250g/l sulfuric acid and 120-180g/l NaCl and kept at 40-60°C is then brought into contact with the chelating resin freed from Bi to elute Sb, and an Sb eluate is obtained. Bi and Sb are extracted from the eluates by separating the anode and cathode with a cation-exchange membrane and using the anode side as a sulfuric acid bath.
TSUCHIDA NAOYUKI
ANDO KOJI
