Removal of Cadmium in the Cold Purification Step by Semi-batch Process

Since the presence of cadmium ions in the zinc production process causes many problems, removing this impurity is necessary at the cold purification stage. This study considers cadmium removal in the cold purification process of the Dandi zinc smelting plant (Zanjan-Iran). To this end, the cadmium cementation was conducted by using zinc dust in the leached solution of the Dandi zinc smelting plant and the synthetic solution. Furthermore, modeling of the system is performed to predict the behavior of cadmium removal. Therefore, cadmium cementation kinetic was studied at different temperatures, and the reaction rate constants were obtained. Then, the governing differential equation of cadmium removal was solved analytically. Finally, verify the model, the outcomes obtained from modeling were compared with the experimental data. Results showed that the mathematical modeling outcomes agree with the experimental data.