Abstract

Ion flotation is a promising method for heavy metal removal from dilute wastewaters. Co-existence of competing ions in solution, however, is detrimental to the process for removing of the target ion. This problem impedes the commercial application on detoxification of real industrial effluents. This study was conducted to estimate the selective removal of cadmium ion in mixed metal solutions. Experiments were carried out using cadmium (II) as the main ion, equimolar amounts of copper (II), zinc (II), calcium (II) and lead (II) as the competing ions, sodium dodecylsulfate (SDS) as collector and ethanol as frother. All metal concentrations in solution test were determinate by Atomic Absorption Spectrophotometer. Cadmium was removed selectively from copper, zinc and calcium solutions. The removal efficiency was declined markedly in presence of lead. The maximum recoveries of Cd from Cu, Zn, Ca and Pb solutions were 80, 84, 83 and 48, respectively. The selectivity coefficients of Cd over Cu, Zn, Ca and Pb were found to be 2.05, 1.63, 0.97 and 0.35, respectively. The Results reveals that the selectivity order between covalent counter ions is closely related to the magnitude of crystalline radius of the ions. © IDOSI Publications, 2011.