Preconcentration and separation of copper (II) with solvent extraction using N,N′-bis(2-hydroxy-5-bromo-benzyl)1,2 diaminopropane

Preconcentration and separation with solvent extraction of Cu(II) from aqueous solution using N,N'-bis(2-hydroxy-5-bromo-benzyl)1,2 diaminopropane (H,L) as the new extractant has been studied. Separation of Cu(II) from other metal ions such as Cd(II), Ni(II), Zn(II), Pb(II), Cr(III), Co(II) and Mn(II) at aqueous solutions of various pH values and complexing agent H2L, has been described. The possible extraction mechanism and the compositions of the extracted species have been determined. The separation factors for these metals using this reagent are reported while efficient methods for the separation of Cu(II) from other metal ions are proposed. From the loaded organic phase, Cu(II) stripping was carried out in one stage with different mineral acid solutions. The stripping efficiency was found to be quantitative in case of HNO3 and HCl. From quantitative evaluation of the extraction equilibrium data, it has been deduced that the complex extracted is the simple 1:1 chelate, CuL. The extraction constant has a value of logK(ex) = -4.05 +/- 0.04. (C) 2002 Elsevier Science B.V. All rights reserved.