Linking leach chemistry and microbiology of low-grade copper ore bioleaching at different temperatures

Abstract

The effects of temperature on chalcocite/pyrite oxidation and the microbial population in the bioleaching columns of a low-grade chalcocite ore were investigated in this study. Raffinate from the industrial bioleaching heap was used as an irrigation solution for columns operated at 20, 30, 45, and 60°C. The dissolution of copper and iron were investigated during the bioleaching processes, and the microbial community was revealed by using a high-throughput sequencing method. The genera of Ferroplasma, Acidithiobacillus, Leptospirillum, Acidiplasma, and Sulfobacillus dominated the microbial community, and the column at a higher temperature favored the growth of moderate thermophiles. Even though microbial abundance and activity were highest at 30°C, the column at a higher temperature achieved a much higher Cu leaching efficiency and recovery, which suggested that the promotion of chemical oxidation by elevated temperature dominated the dissolution of Cu. The highest pyrite oxidation percentage was detected at 45°C. Higher temperature resulted in precipitation of jarosite in columns, especially at 60°C. The results gave implications to the optimization of heap bioleaching of secondary copper sulfide in both enhanced chalcocite leaching and acid/iron balance, from the perspective of leaching temperature and affected microbial community and activity.

Keywords

bioleaching / chalcocite dissolution / microbial community / pyrite dissolution / temperature

References

[1] Watling H.R. The bioleaching of sulphide minerals with emphasis on copper sulphides—A review. Hydrometallurgy, 2006, 84(1-2): 81.

[2] Zhu W., Xia J.L., Yang Y., Nie Z.Y., Zheng L., Ma C.Y., Zhang R.Y., Peng A.A., Tang L., Qiu G.Z. Sulfur oxidation activities of pure and mixed thermophiles and sulfur speciation in bioleaching of chalcopyrite. Bioresour. Technol., 2011, 102(4): 3877.

[3] Vera M., Schippers A., Sand W. Progress in bioleaching: fundamentals and mechanisms of bacterial metal sulfide oxidation — part A. Appl. Microbiol. Biotechnol., 2013, 97(17): 7529.

[4] Brierley J.A. A perspective on developments in biohydrometallurgy. Hydrometallurgy, 2008, 94(1-4): 2.

[5] Petersen J., Dixon D.G. Principles, mechanisms and dynamics of chalcocite heap bioleaching, [in] Microbial Processing of Metal Sulfides, 2007, The Netherlands, Springer 193.

[6] Y. Jia, R.M. Ruan, S.P. Zhong, H.Y. Sun, L.C. Zou, and J.H. Chen, Heap bioleaching of a net-acid generating copper sulfide: comparison of high and low acidity leaching systems, [in] M. Evatz, M.E. Smith, and D.V. Zyl eds. Proceedings of Heap Leach Solutions, Nevada, 2015, p. 357.

[7] Cheng C.Y., Lawson F. The kinetics of leaching chalcocite in acidic oxygenated sulphate-chloride solutions. Hydrometallurgy, 1991, 27(3): 249.

[8] J. Petersen and D.G. Dixon, The dynamics of chalcocite heap bioleaching, [in] C.A. Yong, A.M. Alfantazi, C.G. Anderson, D.B. Dreisinger, B. Harris, and A. James eds. Hydrometallurgy 2003: Fifth International Conference in Honor of Professor Ian Ritchie, Vancouver, 2003, p. 351.

[9] Bolorunduro S.A. Kinetics of Leaching of Chalcocite in Acid Ferric Sulfate Media: Chemical and Bacterial Leaching [Dissertation], 1999, Canada, University of British Columbia 16.

[10] Ruan R.M., Zou G., Zhong S.P., Wu Z.L., Chan B., Wang D.Z. Why Zijinshan copper bioheapleaching plant works efficiently at low microbial activity—Study on leaching kinetics of copper sulfides and its implications. Miner. Eng., 2013, 48, 36.

[11] Niu X.P., Ruan R.M., Tan Q.Y., Jia Y., Sun H.Y. Study on the second stage of chalcocite leaching in column with redox potential control and its implications. Hydrometallurgy, 2015, 155, 141.

[12] Sun H.Y., Chen M., Zou L.C., Shu R.B., Ruan R.M. Study of the kinetics of pyrite oxidation under controlled redox potential. Hydrometallurgy, 2015, 155, 13.

[13] Franzmann P.D., Haddad C.M., Hawkes R.B., Robertson W.J., Plumb J.J. Effects of temperature on the rates of iron and sulfur oxidation by selected bioleaching bacteria and archaea: application of the Ratkowsky equation. Miner. Eng., 2005, 18(13-14): 1304.

[14] Ruan R.M., Liu X.Y., Zou G., Chen J.H., Wen J.K., Wang D.Z. Industrial practice of a distinct bioleaching system operated at low pH, high ferric concentration, elevated temperature, and low redox potential for secondary copper sulfide. Hydrometallurgy, 2011, 108(1-2): 130.

[15] Dew D.W., Rautenbach G.F., Van Hille R.P., Davis-Belmar C.S., Harvey I.J., Truelove J.S. High temperature heap leaching of chalcopyrite: Method of evaluation and process model validation. Proceedings of the International Conference on Percolation Leaching: The Status Globally and in South Africa, 2011 201.

[16] Mutch L.A., Watling H.R., Watkin E.L.J. Microbial population dynamics of inoculated low-grade chalcopyrite bioleaching columns. Hydrometallurgy, 2010, 104(3): 391.

[17] Watling H.R., Collinson D.M., Li J., Mutch L.A., Perrot F.A., Rea S.M., Reith F., Watkin E.L.J. Bioleaching of a low-grade copper ore, linking leach chemistry and microbiology. Miner. Eng., 2014, 56(2): 35.

[18] Lotfalian M., Ranjbar M., Fazaelipoor M.H., Schaffie M., Manafi Z. The effect of redox control on the continuous bioleaching of chalcopyrite concentrate. Miner. Eng., 2015, 81, 52.

[19] DeSantis T.Z., Hugenholtz P., Keller K., Brodie E.L., Larsen N., Piceno Y.M., Phan R., Andersen G.L. NAST: a multiple sequence alignment server for comparative analysis of 16S rRNA genes. Nucleic Acids Res., 2006, 34, 394.

[20] Dopson M., Baker-Austin C., Hind A., Bowman J.P., Bond P.L. Characterization of Ferroplasma isolates and Ferroplasma acidarmanus sp nov., extreme acidophiles from acid mine drainage and industrial bioleaching environments. Appl. Environ. Microbiol., 2004, 70(4): 2079.

[21] Golyshina O.V., Yakimov M.M., Lünsdorf H., Ferrer M., Nimtz M., Timmis K.N., Wray V., Tindall B.J., Golyshin P.N. Acidiplasma aeolicum gen. nov., sp. nov., a euryarchaeon of the family Ferroplasmaceae isolated from a hydrothermal pool, and transfer of Ferroplasma cupricumulans to Acidiplasma cupricumulans comb. nov.. Inter. J. Syst. Evol. Microbiol., 2009, 59(11): 2815.

[22] Johnson D.B. Biodiversity and interactions of acidophiles: Key to understanding and optimizing microbial processing of ores and concentrates. Trans. Nonferrous Met. Soc. China, 2008, 18(6): 1367.

[23] Okibe N., Johnson D.B. Biooxidation of pyrite by defined mixed cultures of moderately thermophilic acidophiles in pH-controlled bioreactors: significance of microbial interactions. Biotechnol. Bioeng., 2004, 87(5): 574.

[24] Slonczewski J.L., Fujisawa M., Dopson M., Krulwich T.A. Cytoplasmic pH measurement and homeostasis in bacteria and archaea. Adv. Microb. Physiol., 2009, 55, 1.

[25] Rawlings D.E., Tributsch H., Hansford G.S. 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, 1999, 145(1): 5.

[26] Bond P.L., Smriga S.P., Banfield J.F. Phylogeny of microorganisms populating a thick, subaerial, predominantly lithotrophic biofilm at an extreme acid mine drainage site. Appl. Environ. Microbiol., 2000, 66(9): 3842.

[27] Liu X.Y., Chen B.W., Wen J.K., Ruan R.M. Leptospirillum forms a minor portion of the population in Zijinshan commercial non-aeration copper bioleaching heap identified by 16S rRNA clone libraries and real-time PCR. Hydrometallurgy, 2010, 104(3-4): 399.

[28] Watkin E.L.J., Keeling S.E., Perrot F.A., Shiers D.W., Palmer M.L., Watling H.R. Metals tolerance in moderately thermophilic isolates from a spent copper sulfide heap, closely related to Acidithiobacillus caldus, Acidimicrobium ferrooxidans and Sulfobacillus thermosulfidooxidans. J. Ind. Microbiol. Biotechnol., 2009, 36(3): 461.

[29] Halinen A.K., Beecroft N.J., Määttä K., Nurmi P., Laukkanen K., Kaksonen A.H., Riekkola-Vanhanen M., Puhakka J.A. Microbial community dynamics during a demonstration-scale bioheap leaching operation. Hydrometallurgy, 2012, 125-126(8): 34.

[30] Edwards K.J., Bond P.L., Gihring T.M., Banfield J.F. An archaeal iron-oxidizing extreme acidophile important in acid mine drainage. Science, 2000, 287(5459): 1796.

[31] Basson P., Gericke M., Grewar T.L., Dew D.W., Nicol M.J. The effect of sulphate ions and temperature on the leaching of pyrite. III.^Bioleaching. Hydrometallurgy, 2013, 133(133): 176.

[32] Abraitis P.K., Pattrick R.A.D., Vaughan D.J. Variations in the compositional, textural and electrical properties of natural pyrite: a review. Int. J. Miner. Process., 2004, 74(1-4): 41.

[33] Wu B., Wen J.K., Chen B.W., Yao G.C., Wang D.Z. Control of redox potential by oxygen limitation in selective bioleaching of chalcocite and pyrite. Rare Met., 2014, 33(5): 622.

[34] Miki H., Nicol M., Velásquez-Yévenes L. The kinetics of dissolution of synthetic covellite, chalcocite and digenite in dilute chloride solutions at ambient temperatures. Hydrometallurgy, 2011, 105(3): 321.