Prevention of Sulfide Leaching through Covalent Coating
The use of benzene-1,3-diamidoethanethiol as a covalent surface coating for the prevention of metal leaching was demonstrated with several sulfide minerals including cinnabar (HgS), pyrite (FeS2), chalcopyrite (CuFeS2), covellite (CuS), galena (PbS), realgar (As4S4) and sphalerite (ZnS). The minerals were coated with sufficient H2BDT to bind the surface metals in a 1:1 ratio. Leaching at pH 1, 3 and 7 was then conducted on both treated and untreated minerals. ICP and CVAFS (for mercury) analyses revealed that the coated minerals showed a dramatic reduction in metal leaching as compared to uncoated control samples. X-ray photoelectron spectroscopy indicated the formation of covalent bonds between the sulphur of the ligand and the metals from the minerals.
K. M. Zaman et al., "Prevention of Sulfide Leaching through Covalent Coating," Main Group Chemistry, Taylor & Francis, Sep 2007.
The definitive version is available at http://dx.doi.org/10.1080/10241220802075723
Keywords and Phrases
Acid mine drainage; Heavy metals; Leaching
Article - Journal
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