China Nonferrous Metallurgy

In a POX leaching zinc refinery in Qinghai province, reversed antimonic salt method was used for purification. For each ton of zinc produced about 70kg of zinc dust was consumed. To reduce zinc dust consumption rate, the refinery introduced B cobalt removal reagent. The B reagent comprises mostly of antimonic salts, arsenic salts, and tannin compounds, in appropriate conditions the reagent can remove cobalt consistently. With Cd concentration at 200~300mL/L in the purification feed, it was found that satisfactory results can be achieved when the reaction takes place at 83℃ for 2 hours, with B reagent dosed at 0.03kg/m³ and spent electrolyte fed at 3L/m3. Industrial applications have show that using B reagent for Co removal can reduce zinc dust consumption per ton of zinc produced by 15kg compared with the reversed antimonic salt method. It is thus concluded that in comparison with conventional cobalt removal reagents, the B Co removal reagent yields better economic outcome and at the same time produces good Co removal efficiency, hence worthy of promotion.