Multi-elemental separation of copper, cobalt, cadmium and nickel in natural waters by means of colloidal gas aphron co-flotation

Abstract

The separation, pre-concentration and multi-elemental determination of Cu, Co, Cd and Ni by co-flotation on Fe(OH)₃ in natural waters and synthetic media, of average and low salinity, using a colloidal gas aphron of sodium lauryl sulphate as an alternative to the conventional flotation on bubbling air or gas, has been studied. The separation process has been optimised by means of both univariate and simplex methods (COFLOT computer program). The results obtained after 5 min of flotation, show recoveries of greater than 90% for each of the elements, at concentrations of ca. 10 p.p.b. The concentration measurements during the optimisation process and those corresponding to the sublates were carried out by means of atomic absorption spectrometry.