Comparação da labilidade de metais empregando voltametria, difusão em filmes finos por gradiente de concentração (DGT) e modelo computacional Comparison of the speciation of trace metals in freshwater employing voltammetry, diffusive gradients in thin films (DGT) and a chemical equilibrium model

Abstract

Speciation of metals in a synthetic freshwater was comparatively evaluated using Anodic Stripping Voltammetry, Diffusive Gradients in Thin Films and a Chemical Equilibrium Model. The labile fractions of Cu and Zn quantified by DGT were similar to the ones measured by ASV. The labile species of Cd and Pb could not be determined by both experimental methods due to the formation of inert complexes with organic ligands in the sample. Despite the differences among the methods, the speciation results obtained by the use of DGT and ASV agreed well with predictions made by the chemical equilibrium model.

Keywords

• trace metals
• speciation
• lability