Organic and inorganic ligands in the

The presence of soluble organic and inorganic ligands in the mixed liquor and the formation of complexes with metals impacts on their removal and decreases the proportion of metals that can be sorbed to activated sludge. The ligands in the mixed liquor form complexes with metals and only a small proportion of the metals remain in ionic form (Cantwell et al, 1982 Laxen and Harrison, 1981 Sterritt and Lester, 1985). The extent depends on the complexa-tion potential of the soluble ligands found in the mixed liquor with the metals (Stephenson and Lester, 1987). 

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