Mathematical prediction of lead removal from carbonate-rich illite

The interaction between heavy metal contaminants and surface forces associa ted with the reactive surfaces of soil particles was studied with the aim o f developing an analytical tool that would permit the prediction of heavy m etal and soil sorption-desorption phenomena. The predictive model developed in this study considers the energy of the interaction developed between a lead contaminant and illitic soil. Since these energy calculations include both inner and outer sphere complexes. energy balance requirements can be r ealistically evaluated with respect to environmental mobility. For a compar ison between the calculated values obtained from the predictive model and e xperimentally obtained measurements, laboratory batch equilibrium tests and electro-kinetic tests were used. These were concerned with the sorption-de sorption determination of illitic soil samples with the lead contaminant in the form of a lead nitrate solution. The force balance of lead ions indica tes that lead ions in the so-called Stern layer, i.e. the first two layers of a water molecule, are non-removable. Good correlations between calculate d and measured values were obtained. (C) 2001 Elsevier Science B.V. All rig hts reserved.