Effect of Solid/Liquid Ratio on the Remobilization of Cu,Pb, Cd and Zn from Polluted River Sediment

The incidence of the solid/liquid ratio on thesolubilization of heavy metals from a polluted riversediment was assessed by batch experiments. Thepercentage of solubilized metal increases stronglywhen the concentration of the sediment-watersuspension decreases from 50 to 0.1 g L^-1. Thissolubilization behavior is described by a simpleequilibrium desorption model on the association of themetals and sediment. The association constantscalculated with this model indicate the affinitybetween the metals and the sediment (Pb > Cu > Zn> Cd). If polluted river sediments are in situresuspended, the decrease of the solid/liquid ratioassociated to this natural event could provoke theremobilization of metals trapped in sediments.