Abstract:The treatment of cadmium dust with a two-stage leaching process was investigated to replace the existing sulphation roast-leaching processes. The process parameters in the first stage leaching were basically similar to the neutral leaching in zinc hydrometallurgy. The effects of process parameters in the second stage leaching on the extraction of zinc and cadmium were mainly studied. The experimental results indicated that zinc and cadmium could be efficiently recovered from the cadmium dust by two-stage leaching process. The extraction percentages of zinc and cadmium in two stage leaching reached 95% and 88% respectively under the optimum conditions. The total extraction percentage of Zn and Cd reached 94%.

Key words: cadmium dusts; neutral leaching; hot acid leaching