Molecular characterization of Zn in Technosols using X-ray absorption spectroscopy

摘要

The bioavailability of heavy metals in the soil is a function of their speciation. The speciation of Zn in Technosols of anthropogenic anomalies in Southern Urals and Southern Russia was studied using X-ray absorption spectroscopy and X-ray diffraction methods based on synchrotron radiation. The studied Technosols are characterized by exceedings of the lithosphere clark for Zn in hundreds of times. Hypergenic changes in the mineral composition of Technosols revealed different types of Zn surrounding. In the Southern Ural soils, six oxygen atoms forming a deformed octahedron coordinate Zn. For contaminated Technosols of Southern Russia, the longs of the Zn-O bonds were determined, which are close to the bonds in ZnSO4, and the mixed version of local surrounding with Zn-S and Zn-O bonds. Studies of metal speciation are of extreme importance for revealing the main mechanisms responsible for the mobility of trace elements such as Zn and understanding its consequences in terms of long-term potential emission by the Technosols.