Study of trace metal partitioning between soil-EDTA extracts and Chelex-100 resin

Besides, a kinetic procedure was developed to study the kinetic of cation exchange from soil-EDTA leachates onto solid-phase resin. The soil calcium content was found to be a controlling factor in the Cu sorption on the Ca-Chelex. Two different kinetic behaviours were observed in calcareous and non-calcareous soils. The dissociation rate of Cu in non-calcareous soil extracts was 10 times higher than that in calcareous ones. Application of kinetic model indicated the presence of two components associated to Cu in non-calcareous samples. This was discussed in terms of metal sorption mechanism from soil solution onto chelating resin.