EXTRACTION OF CU(II), FE(III), GA(III), NI(II), IN(III), CO(II), ZN(II) AND PB(II) WITH LIX(R)984 DISSOLVED IN N-HEPTANE

The solvent extraction of some metal ions with LIX(R) 984 dissolved in n-heptane was studied. The extraction order observed as the pH of the aqueous solution increases is Cu(II) > Fe(III) > Ga(III) > Ni(II) > I n(III) > Co(II) > Zn(II) approximate to Pb(II). The experimental data obtained are explained considering hydroxyoxime association and metal complex solvation. Numerical analysis of the data with the LETAGROP-DI STR program suggested the presence of the CuR2, CuR(2)2HR, FeR3, GaR3, NiR2, InR3, CoR2HR, ZnR2, ZnR(2)3HR and PbR2HR species in the organic phase. Complex formation between the metal cations and the buffers us ed was considered in the calculations. The values of the equilibrium c onstants for the extraction reactions are reported. (C) 1997 Elsevier Science B.V.