ABSTRACT
Solvent extraction provides the basis for important separation and concentration processes that are widely used in hydrometallurgy, waste treatment, effluent purification, and material preparation1-3. In a typical extraction process, the complexing agent, the extractant, plays a key role and is responsible for the phase transfer of one or more species of interest between the particular liquid-liquid phases employed. At present, four categories of metal extractants are used in industry: acidic and chelating cation exchanging reagents as well as solvating and anion exchanging reagents. Typical structure examples are shown in Figure 1.1.
