Author:
Arias-Arce Vladimir,Lovera-Dávila Daniel,J. Guerrero-Rojas José,Blas-Rodriguez Fanny,Molina-Pereyra Ismael
Abstract
The analysis of the variables, bacterial population, and oxidation-reduction potential (ORP) during the bioleaching of sulfide ores by a bacterial strain of Acidithiobacillus ferrooxidans, isolated from acid mine effluent, aims at the solubilization of copper and the liberation of the gold present in an ore containing more than 80% sulfides. It was studied at different pulp densities (1, 2, and 6% - W/V) and with a 9 k medium at different ferrous sulfate concentrations (0, 3, 6, 9, 12, and 15 g/L), keeping temperature and pH constant. The tests were carried out in three consecutive stages, starting with inoculum, whose cell content was 7.05x107 Cell/mL, then the strain with the highest population obtained in the previous stage was used, observing the variation in the periods of adaptation and growth. During the bioleaching of sulfide ores, in the first stage, the maximum bacterial population achieved was 4.75x107 Cell/mL in 24 days with 6 g/L ferrous sulfate, in the second stage, the maximum population was 6.30x107 Cell/mL without the addition of ferrous sulfate, and in the third stage, the bacterial population became 4.51x107 Cell/mL. The exponential characteristic growth of the population started at approximately 13, 8, and 3 days, respectively in each stage.
Reference38 articles.
1. Majima H. How oxidation affects selective flotation of complex sulphide ores. Canadian Metallurgical Quarterly. 1969;8(3):269-273. DOI: 10.1179/cmq.1969.8.3.269
2. Fagundo Castillo JR, González Hernández P, Suárez Muñoz M, Melián Rodríguez C. Relaciones entre potenciales redox y concentraciones de sulfuros en aguas termales de Cuba. Contribución a la educación y protección ambiental. 2005;6:31-44. Available from: https://www.researchgate.net/profile/Patricia-Gonzalez-Hernandez/publication/
3. Wang J, Gan X, Zhao H, Hu M, Li K, Qin W, et al. Dissolution and passivation mechanisms of chalcopyrite during bioleaching: DFT calculation. XPS and electrochemistry analysis. Minerals Engineering. 2016;98:264-278. DOI: 10.1016/j.mineng.2016.09.008
4. Alvarez M. Microbial Treatment of Heavy Metal Leachates. Spain: Gráficas Terrasa. Department of Biotechnology, Lund University; 2009. Available from: https://lup.lub.lu.se/search/publication/24654
5. Arias-Arce VA, Lovera Dávila DF, Paucarima AF, Rojas TL. Correlación del potencial óxido reducción y la población bacteriana durante el estudio de biolixiviación de sulfuros de cobre. Revista del Instituto de investigación de la Facultad de minas, metalurgia y ciencias geográficas. 2021;24(47):19-28. DOI: 10.15381/iigeo.v24i47.20639