Kinetics of ion flotation of Co(II)–EDTA complexes from aqueous solutions

Abstract

Abstract The flotation kinetics of Co(II)-EDTA complexes from aqueous solutions using cetylpyridinium chloride (CPyCl) is studied and discussed in the present work. The effects of many variables on the ultimate recovery and the flotation rate are investigated. The data obtained from solutions of different pH values showed that Co(II)-EDTA complexes are successfully floated at pH 7.8. While at pH 3.4 and 11.2, both the ultimate recovery and the flotation rate are dependent on the concentration of CPyCl. Flotation of Co(II)-EDTA at different air flow rates, CPyCl concentrations and ionic strength showed that the ultimate recovery and the flotation rate are markedly affected. The other parameters (cobalt, EDTA and ethanol concentrations) had no effect on the ultimate recovery, while significantly affected the flotation rate. At the optimum conditions (Co(II) : EDTA = 1:1; CPyCl : Co(II) = 4:1; pH7.8; G = 25 cm3/min), removals more than 99% are achieved for radiocobalt. The classical first-order and the second-order kinetic models are used throughout the work to analyze the experimental kinetic data. At all the studied parameters, the kinetic data of Co(II)-EDTA complexes are better fitted to the classical first-order model.