Kinetic versus equilibrium studies for the speciation of metal complexes with ligands from soil and water

Abstract

The systems under study are recognized as dynamic structures far from equilibrium and a dynamic analysis is recommended. A comparison is made of a kinetic speciation approach with the approach based on a local equilibrium approximation, which is commonly used. The ligand exchange kinetic speciation scheme developed in our laboratories is reviewed and its scope and limits identified. Tools such as laser thermal lensing, fluorescence probes, and combined high-performance liquid chromatography–ultrafiltration, which can be used in kinetic speciation, are evaluated.