Solvent extraction of zinc from chloride solutions

Solvent extraction gains importance in the hydrometallurgical processing of ores, and in concentration and even processing of secondaries, due to development of new organic extractants which selectively extract metals from complex leach solutions. Organic solvents selectively extract the desired metals leaving other constituents in the aqueous raffinate, or sometimes minor impurities are extracted to purify the leach solution for further processing and metal recovery. In the present paper, a review has been made for the extraction and separation of zinc from the chloride solution using various organic reagents viz. acidic, basic and solvating. The paper highlights the extraction of zinc from complex chloride solution containing different impurities, in particular kinetics and mechanism of extraction, species formed in the organic phase, stripping of zinc from the organic phase etc.