The Impact of Different Initial Concentrations of Co, Fe, Mn and KMnO4 on the Efficiency of Cobalt Removal from Zinc Electrolyte Solution

Removal of cobalt from zinc electrolyte solution is one of the most important and difficult steps in zinc production using hydrometallurgy method. The impact of initial concentrations of cobalt, manganese, and Fe and amounts of potassium permanganate on the efficiency of cobalt removal by potassium permanganate from zinc electrolyte solution was investigated in this research. The results indicated that the higher the initial concentration of cobalt, manganese, and Fe is, the lower the cobalt removal amount will be; however, as the amount of potassium permanganate increases, the efficiency of cobalt removal will enhance. It was also found that, in order to make a permissible level of the dissolved cobalt, the consumption of potassium permanganate should be increased as the concentration of cobalt, Fe, and manganese increases. If the concentration of manganese is more than 500 mg/L, it can impact the reduction of the efficiency of cobalt removal to a great extent; but when the initial concentration of cobalt is high, the significance of the impact of the initial amounts of manganese would decrease. Additionally, if the manganese concentration is less than 200 mg/L, the optimal removal of cobalt (less than 2 ppm) will not occur under any circumstances. The results also indicate that if the potassium permanganate concentration is 1 g/L or lower, the Fe ions in the solution will drastically reduce the cobalt removal efficiency.