The solvent extraction of zinc with dithizone

The extraction of 10^-5M zinc ion from aqueous solution into an organic solvent 1.8 . 10–3m in dithizone has been investigated. The effects of pH, other ions in the aqueous phase including ions which complex with zinc, and various organic solvents have been investigated. Ions which complex with zinc (citrate, oxalate, nitrilotriacetate, ethylenediaminetetracetate) change the position and/or shape of the extraction curve. Changes in the organic solvent alter the position of the curve, this alteration being qualitatively related to the solubility of dithizone in the organic solvent. Spectra for dithizone and for zinc dithixonate in several organic solvents have also been determined.