Characteristics and Removal Efficiency of Washing with Different Reagent for Soil Contaminated by Leads of Various Sources

Lead is a common pollutant found in soil. The characteristics of lead contaminated soil may vary depending on various sources of lead pollutants and different soils. In this research, samples were collected from soils contaminated by lead of different sources including discarded slag, lead smelting plant and gunnery firing range for conducting characteristic analyses. The samples were also subject to washing using seven different cleaning agents including acids such as HNO3 and HCl, cationic exchangers such as AlCl3, FeCl3, CaCl2 and MgCl2, as well chelating agent such as EDTA-4Na to study the efficiency of these agents of removing leads of various bindings in the contaminated soil. The results show that he most effective cleaning agents are HNO3, HCl, and EDTA-4Na, FeCl3 and AlCl3 for the exchangeable fraction of lead, HNO3, HCl and FeCl3 for carbonate bond fraction of lead, HNO3, HCl followed by EDTA-4Na and FeCl3 for Fe-Mn oxides bond fraction of lead; HNO3, HCl and FeCl3 for the organic bond fraction lead and HCl for the residual fraction of lead.