Special characteristics of natural heterogeneous complexants

All groups of homologous complexants (PROM, AROM, humics, proteins, polysaccharides, cell wall debris, clays, metal oxyhydroxides) exhibit at least three major properties  

For complex heterogeneous natural materials, even the determination of the total number of complexing groups is not straightforward (Buffle and Filella, 1995 Ruzic, 1996 Ruzic and Pecar, 1997 Turoczy and Sherwood, 1997 Presa et al., 1998). 

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