Copper(II) extraction from phosphoric acid media by 5-dodecylsalicylaldoxime (LIX 622)

The extraction of Cu( II) from phosphoric acid media (0.4 - 7.3 M) by the commercial reagent LIX 622 in toluene has been studied. Experimental results have been treated numerically and the formation in the organic phase of the complex CuR2, HR being 5-dodecylsalicylaldoxime, has been proposed. Values of the conditional extraction constants, which increase with the phosphoric acid concentration, are given. Organic extracts have been analyzed by EPR spectroscopy. The presence of a square planar complex of Cu( II) has been deduced confirming the stoichiometry CuR2.