Humic interactions with metals

REACTIVITY OF HUMIC SUBSTANCES IN AMENDED SOILS 4.5.1. Interaction with Metal Ions... 

In the course of time it has been unambiguously demonstrated that humic- and fulvic acids interact with metal cations by forming rather stable, and often soluble complexes(1 2). The increasing awareness of a possible pollution of the environment, e.g. in connection with the disposal of nuclear waste, emphasizes the need for additional knowledge about the interaction between relevant metal ions, e.g. radionuclides commonly present in nuclear waste, and humic substances. The possible presence of soluble and rather stable complexes may play an important role in determining the migration behavior of the metal ions under shallow land burial conditions. The influence of humic- and fulvic acids on the migration behavior of metal ions has been discussed previously (2-6),... 

Allison, J.D. and Perdue, E.M. (1994) Modeling metal-humic interactions with MINTEQA, in N. Senesi and T.M. Miano (eds.), Humic Substances in the Global Environment and Implications on Human Health. Elsevier Science, Amsterdam, pp. 927-942. 

Allison, J.A. Perdue, E.M. (1994) Modelling metal-humic interactions with MINTEQA2. Proceedings of the 6th International Meeting of the International Humic Substances Society, Bari, Italy. 

S.7.3.2. INTERACTION OF HUMIC SUBSTANCES WITH METALS A discussion of this topic must always start with a statement of the difficulties... 

Kula, P. and Navratilova, Z. (1994) Humic acids interactions with metal salts incorporated into the carbon paste electrode. Electroanalysis, 6, 1009-1013. 

Choppin, G. R. Clark, S. B. 1991. The kinetic interactions of metal ions with humic acids. Marine Chemistry, 36, 27-38. 

A series of complexes of 2,6-dihydroxybenzoate has been prepared and studied as model compounds for the interactions of metal ions with humic acids.65,183... 

Since the metal ions interact with the humate anions to form the complexes the dissociation of the humic acid should be taken into account ... 

It shall be remembered that part of the metal ions, which are not engaged by the humic acid complexation, may interact with the buffer solution, containing a certain concentration of 1 buffer -ligands1, [l], i.e. [M]f < [m]q. The metal ion - buffer-ligand interaction is given by the following set of equations ... 

---