Influence of sulfur source on nickel and cobalt bioleaching from laterite tailings using Acidithiobacillus thiooxidans
Laterites are oxide ores widely distributed in the equatorial regions. Lateritic deposits usually consist of three layers, namely the limonitic, the saprolite and the garnieritic layer. Iimonite, which comprises the top lateritic layer, is a homogeneous ore consisting mainly of goethite with which nickel is associated. The Cuban nickel deposits are recognized as one of the biggest deposits in the world. The technology carbonate-amoniacal ( CARON) is usually used for its recovery. Tailings from this process contain metals partially oxidized that can not be treated for metal recovery because of its recalcitrant mineralogical composition. Thus, it is crucial to look for sustainable technologies to treat this kind of mine waste. Previous studies have shown that sulfur oxidizing bacteria instead of fungi can be used for treating this metallurgic residue (Coto et al. 2007). However, more detailed understanding about the action mechanism with sulfur oxidizing bacteria is required. In this paper we studied the influence of the three sulfur compounds elemental sulfur, thiosulfate, and tetrathionate on bioleaching of laterite tailings by two strains of Acidithiobacillus thiooxidans. The numbers of total and of living cells in tailings material were quantified after staining of cells on filters with SYBR Green and by CARD - FISH, respectively, and subsequent counting under a fluorescence microscope. For comparison cell numbers were determined by the most probable number ( MPN) cultivation technique and by quantitative real-time PCR as well. The number of bacteria correlated with the amount of metal solubilisation. Elemental sulfur addition resulted in a higher bioleaching efficiency than the addition of thiosulfate and tetrathionate.
nickel cobalt laterite tailings Acidithiobacillus thiooxidans elemental sulfur thiosulfate tetrathionate
Orquidea Coto Axel Schippers
Laboratory of Metals, Department of Microbiology, Faculty of Biology, University of Havana, Cuba Federal Institute for Geosciences and Natural Resources (BGR), Stilleweg 2, 30655, Hannover, Germany
国际会议
The 19th International Biohydrometallurgy Symposium(第19届国际生物湿法冶金大会 IBS2011)
长沙
英文
579-583
2011-09-18（万方平台首次上网日期，不代表论文的发表时间）