LAUSR

Filter cake, a residue from the ethanol industry, has a high content of organic matter and presents promising characteristics to act in the remediation of potentially toxic metals. The objective of this paper was to evaluate the characteristics of humic materials extracted from filter cake and investigate their interaction with toxic metals and apply to filter cake in natura and in situ. The complexation capacity of humic matter extracted from filter cakes indicated their high chelating potential and the organic matter importance in potentially toxic metals’ complexation capacity of this type of material. The humic substances extracted from filter cakes showed different affinities for potentially toxic metals (humic material Alagoas: Cr < Ni < Cd < Cu < Pb and humic material from São Paulo: Cd < Ni < Cr < Cu < Pb). Although the affinity order of the metals by humic material has been different from the data obtained from the controlled conditions (laboratory), “in situ” studies showed a high retention of potentially toxic metals by adsorptive materials.