[Study on phase distribution and release of heavy metal in pyrite using sequential extraction procedure and ICP-MS]

Heavy metal elements of V, Cr, Mn, Co, Ni, Cu, Zn, Sr, Mo, Cd, Sb, Ba and Pb were determined by ICP-MS. The linear ranges of determination for these elements were obtained, and the correlation coefficients were larger than 0.997. The detection limit ranges were from 0.005 to 0.01 microg x L(-1) and the RSDs were lower than 5%. Phase distributions of heavy metals in pyrite were analyzed by ICP-MS with sequential extraction procedure. The result showed that Pb was the main heavy metal in pyrite and its total content was 830 mg x kg(-1). Pb existed mostly in carbonate or galena (PbS) phase of pyrite and the proportion was 56.9%. Pb existed less in iron oxides with 29.7% in proportion, and least in sulfide and silicate with 3.5% and 9.9%, respectively. The release of Pb in pyrite was primary in natural environment, but the release of Cr and Cd was not be ignorable, too.