Toxicity of flotation reagents to moderately thermophilic bioleaching microorganisms
- 265 Downloads
The toxicity of 15 flotation reagents (including xanthates, carbamates, thiophosphates, a mercaptobenzthiazole and a frothing reagent) used for concentrating sulfide minerals to five species of mineral-oxidising, moderately thermophilic and acidophilic microorganisms was assessed. The acidophiles tested included four bacteria (a Leptospirillum isolate, Acidimicrobium ferrooxidans, Acidithiobacillus caldus and a Sulfobacillusisolate) and one archaeon (a Ferroplasma isolate). There was wide variation both in terms of the relative toxicities of the different flotation reagents and the sensitivities of the microorganisms tested. In general, the dithiophosphates and the mercaptobenzothiol were the most toxic, while the Leptospirillum and Ferroplasma isolates were the most sensitive of the acidophilic microorganisms. The significance of these findings, in view of the expanding application of ore concentrates bioprocessing, is discussed.
Unable to display preview. Download preview PDF.
- Brierley JA, Brierley CL (2001) Present and future commercial applications in biohydrometallurgy. Hydrometallurgy 59: 233–240.Google Scholar
- Golyshina OV, Pivovarova TA, Karavaiko GI, Kondrat'eva TF, Moore ERB, Abraham WR, Lunsdorf H, Timmis KN, Yakimov MM, Golyshin PN (2000) Ferroplasma acidiphilum gen. nov., sp. nov., an acidophilic, autotrophic, ferrous-iron-oxidizing, cellwall-lacking, mesophilic member of the Ferroplasmaceae fam. nov., comprising a distinct lineage of the Archaea. Int. J. Syst. Evol. Microbiol. 50: 997–1006.Google Scholar
- Hallberg KB, Johnson DB (2001) Biodiversity of acidophilic prokaryotes. Adv. Appl. Microbiol. 49: 37–84.Google Scholar
- Loon HY, Madgwick J (1995). The effect of xanthate flotation reagents on bacterial leaching of chalcopyrite by Thiobacillus ferrooxidans. Biotechnol. Lett. 17: 997–1000.Google Scholar
- Lovley DR, Phillips EJP (1987) Rapid assay for microbially reducible ferric iron in aquatic sediments. Appl. Environ. Microbiol. 53: 1536–1540.Google Scholar
- Okibe N, Johnson DB (2001) Bioleaching of pyrite by defined mixed cultures of moderately thermophilic acidophiles. In: Ciminelli VST, Garcia Jr O, eds. Biohydrometallurgy: Fundamentals, Technology and Sustainable Development. Process Metallurgy 11A. Amsterdam: Elsevier, pp. 443–451.Google Scholar
- Rawlings DE, ed. (1997) Biomining: Theory, Microbes and Industrial Processes. Georgetown, TX: Springer-Verlag/Landes Biosciences.Google Scholar
- Rawlings DE, Tributsch H, Hansford GS (1999a) Reasons why Leptospirillum-like species rather than Thiobacillus ferrooxidans are the dominant iron-oxidizing bacteria in many commercial processes for the biooxidation of pyrite and related ores. Microbiology 145: 5–13.Google Scholar
- Rawlings DE, Coram NJ, Gardner MN, Deane SM (1999b) Thiobacillus caldus and Leptospirillum ferrooxidans are widely distributed in continuous flow biooxidation tanks used to treat a variety of metal containing ores and concentrates. In: Amils R, Ballester A, eds. Biohydrometallurgy and the Environment toward the Mining of the 21st Century, Process Metallurgy 9A. Amsterdam: Elsevier, pp. 777–786.Google Scholar
- Sand W, Gehrke T, Hallmann R, Schippers A (1995) Sulfur chemistry, biofilm, and the (in)direct attack mechanism: a critical evaluation of bacterial leaching. Appl. Microb. Biotechnol. 43: 961–966.Google Scholar
- Tuovinen OH (1978) Inhibition of Thiobacillus ferrooxidans by mineral flotation reagents. Eur. J. Appl. Microbiol. Biotechnol. 5: 301–304.Google Scholar
- Valdivia DNU, Chaves AP (2001) Influence of flotation compounds on the bioleaching process using Thiobacillus ferrooxidans. In: Ciminelli VST, Garcia Jr O, eds. Biohydrometallurgy: Fundamentals, Technology and Sustainable Development. Process Metallurgy 11A. Amsterdam: Elsevier, pp. 159–166.Google Scholar