Document Type : Original Research Paper

Authors

1 Faculty of Mining, Petroleum & Geophysics Engineering, Shahrood University of Technology, Shahrood, Iran

2 Research and Development Center of Sarcheshmeh Copper Complex, Rafsanjan, Iran

Abstract

Due to the increasing consumption of lime in the flotation process to increase the pH of the system and create an alkaline environment, as well as its gradual increase in cost, the attention of researchers has been drawn to perform flotation operations in a neutral environment. Halophilic bacteria have the potential to replace flotation reducers such as lime because flotation can be done with their help at neutral pH as well. Also, due to the buffer effect of sea water, which is the chosen medium for bio-flotation, the use of bio-flotation method reduces the use of drinking water, and also reduces the consumption of chemicals. In this research work, five types of halophilic bacteria are studied for pyrite bio-depression and chalcopyrite flotation. Bio-flotation experiments are conducted using Hallimond tubes, and the bacteria Halobacillus sp., Alkalibacillus almallahensis, and Alkalibacillus sp. had better performance in pyrite depression and chalcopyrite flotation than other bacteria. The recovery of pyrite depression when using them was 30.9, 30.3, and 34.0 %, respectively, and the recovery of chalcopyrite flotation by them was equal to 52.9, 68.6, and 55.7, respectively, which indicates the high selectivity of these bacteria in flotation. In addition to the above tests, the effect of the combination of these three types of bacteria on pyrite depression and chalcopyrite flotation was also studied. The results obtained indicate that in the combination (mix) test of all three types of bacteria (33.3% of each type), pyrite was depressed better than other tests, and its recovery was 27.5%, which was lower than the single bacteria tests. Also, the effect of the combination of these three types of bacteria on the flotation of chalcopyrite is investigated, and its recovery was 72.6%, which was higher than the single bacteria tests. On the other hand, considering that the recovery of chalcopyrite in the three-bacteria combination tests was is higher than the single-bacteria and two-bacteria tests, it can be concluded that the combination of all three bacteria can cause a better synergism and improve their performance in micro-flotation tests.

Keywords

[1]. Houot, R. (1983). Beneficiation of iron-ore by flotation–review of industrial and potential applications. International Journal of Mineral Processing, 10, 183–204.
[2]. Consuegra, G. L., Kutschke, S., Rudolph, M. and Pollmann, K. (2020). Halophilic bacteria as potential pyrite bio-depressants in Cu-Mo bioflotation. Minerals Engineering, 145, 106062.
[3]. Yin, J., Chen, J.C., Wu, Q. and Chen, G.Q. (2015). Halophiles, coming stars for industrial biotechnology. Biotechnology Advances, 33, 7, 1433 – 1442.
[4]. Oren, A. (1999). Bioenergetic aspects of halophilism. Microbiology and Molecular Biology Reviews, 334–348.
[5]. Oren, A. (2002). Diversity of halophilic microorganisms: Environments, phylogeny, physiology, and applications. Journal of Industrial Microbiology & Biotechnology, 28, 56–63.
[6]. Oren, A. (2008) Microbial life at high salt concentrations: phylogenetic and metabolic diversity. Saline Systems, 4:2.
[7]. Quillaguaman, J., Guzman, H., Van-Thuoc, D. and Hatti-Kaul, R. (2010). Synthesis and production of polyhydroxyalkanoates by halophiles: current potential and future prospects. Applied Microbiology and Biotechnology, 85, 6, 1687–1696.
[8]. Roberts, M.F. (2005). Organic compatible solutes of halotolerant and halophilic microorganisms. Saline Systems, 1:5, 1–30.
[9]. Delgado-García, M., Valdivia-Urdiales, B., Aguilar-González, C.N., Contreras-Esquivel, J.C. and Rodríguez-Herrera, R. (2012). Halophilic hydrolases as a new tool for the biotechnological industries. J Sci Food Agric, 92, 2575–2580.
[10]. Hozzein, W.N., Reyad, A.M., Abdel Hameed, M.S. and Ali, M.I.A. (2013). Characterization of a new protease produced by a thermohaloalkali tolerant Halobacillus strain. Journal of Pure and Applied Microbiology, 7,509–515.
[11]. Louis, P. and Galinski, E.A. (1997). Characterization of genes for the biosynthesis of the compatible solute ectoine from Marinococcus halophilus and osmoregulated expression in Escherichia coli. Microbiology, 143, 1141–1149.
[12]. Vargas, C., Argandoña, M., Reina-Bueno, M., Rodríguez-Moya, J., Fernández-Aunión, C. and Joaquín, J.N. (2008). Unravelling the adaptation responses to osmotic and temperature stress in Chromohalobacter salexigens, a bacterium with broad salinity tolerance. Saline Systems, 4:14.
[13]. Ventosa, A., Nieto, J.J. and Oren, A. (1998). Biology of moderately halophilic aerobic bacteria. Microbiology and Molecular Biology Reviews, 62, 2, 504–544.
[14]. Cohen, R. and Exerowa, D. (2007). Surface forces and properties of foam films from rhamnolipid biosurfactants. Advances in Colloid and Interface Science, 134–135, 24–34.
[15]. Sharma, P.K., Hanumantha Rao, K., Natarajan, K.A. and Forssberg, K.S.E. (2000). Bioflotation of sulphide minerals in the presence of heterotrophic and chemolitotrophic bacteria. In: Massacci, P. (Ed.), Proc. XXI International Mineral Processing Congress (IMPC), Developments in Mineral Processing, No. 13. Elsevier, B8a, pp. 93–103.
[16]. Hosseini Tabatabaei, R. (2003). Feasibility study of bioflotation of Sarcheshmeh copper sulfide ore. Master of Science Thesis in Mineral Processing, University of Tehran, In Persian.
[17]. Kolahdoozan, M., Tabatabaei, H., Oliazadeh, M., Noaparast, M., Tabatabaei, Y.S.M., Shahverdi, A.R., Eslami, A. and Manafi, Z. (2004). Bioflotation of Sarcheshmeh copper sulphide ore. Particle Size Enlargement in Mineral Processing, Proceedings of the 5th UBC-McGill Biennial International Symposium on Fundamentals of Mineral, COM 2004, August 22-25, 43rd Annual Conference of Metallurgists of CIM, August 22 - 25, 2004, Hamilton, Toronto, Canada.
[18]. Hosseini, T.R., Kolahdoozan, M., Tabatabaei, Y.S.M., Oliazadeh, M., Noaparast, M., Eslami, A., Manafi, Z. and Alfantazi, A. (2005). Bioflotation of Sarcheshmeh copper ore using Thiobacillus ferrooxidans bacteria. Minerals Engineering, 18, 371–374.
[19]. Botero, A.E.C., Torem, M.L. and de Mesquita, L.M.S. (2008). Surface chemistry fundamentals of biosorption of Rhodococcus opacus and its effect in calcite and magnesite flotation. Minerals Engineering, 21, 83–92.
[20]. Govender, Y. and Gericke, M. (2011). Extracellular polymeric substances (EPS) from bioleaching systems and its application in bioflotation. Minerals Engineering, 24, 1122–1127.
[21]. Khoshdast, H. (2011). Investigating the possibility of flotation of copper ores using Rhamnolipid biosurfactants as frother. PhD dissertation in Mineral Processing, Shahid-Bahonar University of Kerman, In Persian.
[22]. Kim, G., Choi, J., Choi, S.Q., Song, Y. and Kim, H. (2016). Bioflotation of malachite from complex system using Rhodococcus opacus. International Mineral Processing Congress (IMPC), XXVIII International Mineral Processing Congress Proceedings.
[23]. Olivera, C.A.C., Merma, A.G., Puelles, J.G.S. and Torem, M.L. (2017). On the fundamentals aspects of hematite bioflotation using a Gram positive strain. Minerals Engineering, 106, 55 – 63.
[24]. Kim, G., Choi, J., Silva, R.A., Song, Y. and Kim, H. (2017). Feasibility of bench-scale selective bioflotation of copper oxide minerals using Rhodococcus opacus. Hydrometallurgy, 168, 94–102.
[25]. Abedi Ashkavandi, R., Azimi, E. and Raouf Hosseini, M. (2022). Bacillus licheniformis a potential bio-collector for barite-quartz selective separation. Minerals Engineering, 175, 107285.
[26]. Simões, C.R., Hacha, R.R., Merma, A.G. and Torem, M.L. (2020). On the recovery of hematite from an iron ore fine fraction by electroflotation using a biosurfactant. Minerals. 10 (12):1057.
[27]. El-Sayed, S., El-Shatoury, E.H., Abdel-Khalek, N.A., Abdel-Motelib, A. and Abdel Khalek, M.A. (2021). Influence of Bacillus cereus-Gold interaction on bio-flotation of gold in the presence of potassium butyl xanthate. Biointerface Research in Applied Chemistry. 11 (5): 13005–13018.
[28]. Pineda, G.A.C. and Godoy, M.A.M. (2019). Effect of Thiobacillus thiooxidans-cysteine interactions on pyrite biooxidation by Acidithiobacillus ferrooxidans in the presence of coal compounds. Brazilian Journal of Chemical Engineering. 36 (2): 681–692.
[29]. Çelik, P.A., Çakmak, H. and Öz Aksoy, D. (2021). Green bioflotation of calcite using surfactin as a collector. Journal of Dispersion Science and Technology, 1–11.
[30]. Moreno, P.A., Aral, H., Cuevas, J., Monardes, A., Adaro, M., Norgate, T. and Bruckard, W. (2011). The use of seawater as process water at Las Luces copper–molybdenum beneficiation plant in Taltal (Chile). Minerals Engineering, 24, 852–858.
[31]. Pérez-Davó, A., Aguilera, M., Ramos-Cormenzana, A. and Monteoliva-Sánchez, M. (2014). Alkalibacillus almallahensis sp. nov., a halophilic bacterium isolated from an inland solar saltern. International Journal of Systematic and Evolutionary Microbiology, 64, 2066–2071.
[32]. Mesbah, N.M. and Wiegel, J. (2014). Purification and biochemical characterization of halophilic, alkalithermophilic protease AbCP from Alkalibacillus sp. NM-Fa4. Journal of Molecular Catalysis B: Enzymatic, 105, 74–81.
[33]. Samaei‑Nouroozi, A., Rezaei, S., Khoshnevis, N., Doosti, M., Hajihoseini, R., Khoshayand, M.R. and Faramarzi, M.A. (2015). Medium‑based optimization of an organic solvent‑tolerant extracellular lipase from the isolated halophilic Alkalibacillus salilacus. Extremophiles, 19, 5, 933 – 947.
[34]. Schäfer, A., Harms, H. and Zehnder, A.J.B. (1998). Bacterial accumulation at the air-water interface. Environmental Science & Technology. 32 (23): 3704–3712.
[35]. Tolley, W., Kotlyar, D. and Van Wagoner, R. (1996). Fundamental electrochemical studies of sulfide mineral flotation. Minerals Engineering, 9, 6, 603 – 637.
[36]. Moslemi, H. and Gharabaghi, M. (2017). A review on electrochemical behavior of pyrite in the froth flotation process. Journal of Industrial and Engineering Chemistry, 47, 1–18.
[37]. Banat, I. M., Makkar, R.S. and Cameotra, S.S. (2000). Potential commercial applications of microbial surfactants. Applied Microbiology and Biotechnology. 53 (5): 495–508.