Alterations in surfaces and textures of minerals during the bacterial leaching of a complex sulfide ore |
| |
| Authors: | Lasse Ahonen Olli H Tuovinen |
| |
| Institution: | 1. Geological Survey of Finland , Espoo, SF‐02150, Finland;2. Department of Microbiology , Ohio State University , Columbus, OH, 43210–1292 |
| |
| Abstract: | Abstract The purpose of the work was to characterize changes in surface textures of minerals during the biological leaching of a complex sulfide ore. The ore contained pyrrhotite (FeI_xS), pyrite (FeS2), sphalerite (ZnS), pentlandite (Ni,Fe,Co)9S8], and chalcopyrite (CuFeS2). Several mixed cultures were initially screened using the ore material as the sole substrate. Shake flask leaching experiments showed no major differences among test cultures, which were all derived by enrichment techniques using environmental samples collected from a mine site. Leached pyrrhotite surfaces were invariably surrounded by a dark rim of elemental S. A reaction zone was also associated with leached sphalerite grains. Chemical analyses of leach solutions indicated that the relative ranking of biological leaching of the sulfide minerals was Zn > Ni > Co > Cu. Microscopic observations were in keeping with this rankin |
| |
| Keywords: | Chalcopyrite oxidation galvanic coupling leaching of sulfide minerals pentlandite oxidation pyrite oxidation pyrrhotite oxidation sphalerite oxidation sulfur formation |
|
|
