Determination of Partition Coefficients of Metals in Natural Tropical Water

Abstract

The values for the partition coefficient (Kd) were calculated for Ca, Mg, Cd, Cr, Cu, Fe, Mn, Pb, Ni, and Zn at 19 sites in the Capivara hydroelectric reservoir in Brazil. It was found that the relative values of Kd follow the order: Cr > Mn > Fe > Cu > Zn > Ni > Pb > Ca > Cd, differing from the values reported for Kd in aquatic systems in the northern hemisphere. A hierarchical cluster analysis and linear correlations showed that Cr is strongly associated with Fe and Cu, and that Cd is the only metal found in complexation with organic matter, explaining its higher solubility.