Optimised method for extraction of mobile species of heavy metals from polluted soils

Abstract

The paper proposed an optimized extraction method used for extraction of mobile forms of heavy metals (Cu, Cd, Pb and Zn) from different types of polluted soils with clay structure. This study presents a comparison between the results obtained using SR ISO 14870/1999 with 5 successive extractions and a ratio of soil:solution of 1:2 with the results obtained experimentally for one single chemical extraction and different ratios between soil and solution (1:5, 1:7, 1:10). The results obtained put in evidence similar concentration of mobile species and indicated that modified standard method (ratio 1:10) is a good analytical method for estimation of mobile species concentration of heavy metals from polluted soils. The total content and mobile forms of heavy metals were analysed with AAS technique, using an ATI UNICAM SOLAR equipment.