Solvent extraction is an efficient and selective separation methodapplied to hydrometallurgical systems. It is commonly used in thepurification and concentration of non-ferrous metals from industrialliquors, such as zinc, nickel, cobalt, copper, rare earth metals, andradioactive elements. This method has also been applied for metalsrecovery from solid wastes and/or effluents.In a simplified manner, the solvent extraction process consists of anextraction step followed by a stripping step. In the extraction step, anaqueous phase containing the metal of interest, such as a leaching liquor, is placed in contact with an organic phase, which is immiscible tothe aqueous phase and which contains the extractant dissolved in theorganic solvent. The extractant is an extracting agent, i.e., a reagentwhich selectively extracts the desired metal(s) according to given