SOLVENT-EXTRACTION OF CADMIUM(II) FROM ACIDIC MEDIA BY CYANEX-302

The extraction of Cd(II) from chloride media of 1.0 M ionic strength b y the commercial extractant Cyanex 302 in kerosene has been studied ov er a range of pH and reagent concentrations. The data have been analyz ed both graphically and numerically to determine the stoichiometry of the extracted complexes and their extraction constants. The species Cd R(2)(HR) and CdR(2)(HR)(2), HR being the active component in the comme rcial extractant, bis (2,4,4-trimethylpentyl)thiophosphinic acid, have been found to be responsible for the extraction behaviour observed.