Resumo

GARCIA-ARREOLA, M.E. et al. Comparison of static leaching essays of toxic elements in tailings. Rev. Mex. Ing. Quím [online]. 2015, vol.14, n.1, pp.109-117. ISSN 1665-2738.

Mining is still one of the main economic activities in Mexico. However, mineral exploitation is extensive, leading to a considerable generation of waste that has accumulated without any control. The present study used historical tailings from Guanajuato mining district, in the town, of Monte San Nicolas and Peregrina. Batch leaching tests were performed with three different methodologies: PECT method (extraction procedure toxic constituents) described in the NOM-053-SEMARNAT-1993, the NOM-141-SEMARNAT-2003 (CO₂ acidified water) and the SPLP (Synthetic Precipitation leaching Procedure) 1312 (EPA, 1989). The elements studied were: As, Pb, Mn, Zn, Cd and Cr. According to variance analysis, there were significant differences between the types of extractant. The results show that the release of Pb and Zn in the waste is a function of the pH of the extractant. The release for As, Zn, Cd and Cr depend on the degree of adsorption to manganese and aluminum oxides. For all elements studied the release was greater with the TCLP extract, influenced by the acidity and the organic ligand.

Palavras-chave : leaching; waste mining; metals; tailing; static leaching test.