Hydrometalurgiczne procesy wydzielania i rozdzielania jonów cynku i kadmu

This paper is a review of hydrometallurgical processes of removal and separation of zinc(II) and cadmium(II) ions from chloride, sulphate and other medium aqueous solutions. The following physicochemical methods were described: solvent extraction, transport across liquid membranes (bulk liquid membranes, emulsion liquid membranes, supported liquid membranes and polymer liquid membranes [1,2]), and foam separation (ion flotation, precipitate flotation, and adsorbing colloid flotation [3,4]). In solvent extraction and transport through liquid membranes, the derivatives of phosphoroorganic compounds and amines, as well as nonionic crown ethers were used as extractants and ion carriers. As collectors for foam separation the regular surfactants as well as ionizable lariat ethers were applied. It was found, that the main factor influencing the separation selectivity of zinc(II)/cadmium(II) was the diameter of cavity in the crown ether of applied macrocycles. In all physicochemical processes the removal and separation selectivity of Zn(II) and Cd(II) are influenced by the physical properties of an aqueous phase, i.e. pH, ionic strength, as well as metal ions concentration.