EFFECT OF HYDROGEN-ION CONCENTRATION ON THE EXTRACTION OF COBALT, NICKEL, CADMIUM AND LEAD WITH APDC-MIBK - TIME STABILITY OF THE EXTRACTS

The extraction of cobalt, nicke cadmium and lead ions by means of APDC/MIBK has been studied at various acidities of the aqueous phase (pH 0.2-6). Lead and nickel are extracted equally well over this pH-range, while cobalt and cadmium require pH > 1. The time stability of the extracted complexes in MIBK increases in the order cadmium < lead < nickel < cobalt. The decomposition of the complexing agent or the metal complexes is rapid in the two-phase system MIBK/water. © 1979.