[Determination of active species of heavy metals in sewage sludge by ICP-MS].

Sewage sludge samples for the research from the sewage disposal plants of the north, Mantang River and Xiannu River in Shenyang were extracted and separated by H2O, HAc and organic solvents of different polarities. The active species of Cd, Pb, Cu, Zn and Cr existing in the sewage sludge were determined by ICP-MS, and the regularity and influential factors were studied under the alternation of environmental conditions. The results showed that the content of acid-soluble heavy metals was more than that of water-soluble ones, and both had coincident regularity under the alternation of time and temperature; the content of the organic solvents was positively correlated to the solvent polarity. The acid-soluble heavy metals were more active during the course of transforming, and the activity sequence of heavy metals in the same species was: water-soluble Zn>Cu>Cd> Pb>Cr, acid-soluble Cd>Cr>Cu>Zn>Pb, and organic-soluble Pb>Cd>Cr>Cu>Zn.