Effect of Dissolved Organic Matter on the Adsorption of Heavy Metals in Soils

This study investigated the effect of leachate DOM on the adsorption of Cu, Cd, Pb and Zn in the typical cinnamon soil in Northern China. The adsorption experiments were conducted under the conditions of isotherm at 15, 25 35°C and at various acidities (pH=5-9). The results revealed that the process of soil adsorb these metals is accord with the adsorption isotherm formula of S=KCN and S=SmC/(C+1/K). However, the effect of leachate DOM on the adsorption of four metals tended to vary with the change of pH. The adsorptions of Cd, Pb and Zn were elevated by the increase of the temperature.