Shahrood University of Technology Journal of Mining and Environment 2251-8592 12 4 2021 10 01 Optimization of Chalcopyrite Bioleaching using Two Different Adaptation Methods: Top-Down and Bottom-Up 1055 1064 2269 10.22044/jme.2021.11108.2089 EN Z. Manafi Department of Microbiology, Jahrom Branch, Islamic Azad University, Jahrom, Iran M. Kargar Department of Microbiology, Jahrom Branch, Islamic Azad University, Jahrom, Iran F. Kafilzadeh Department of Microbiology, Jahrom Branch, Islamic Azad University, Jahrom, Iran 0000-0003-2506-7140 Journal Article 2021 08 15 Optimization of the effective parameters in the copper bioleaching of chalcopyrite concentrates (CuFeS₂) is studied by moderately thermoacidophilic microorganisms. The microorganisms with extensive metabolic properties are used in two different ways: 'top-down' and 'bottom-up'. The bioleaching experiments are performed based on the parameters of silver, activated charcoal, concentrate type (Sarcheshmeh and Miduk), and a type of bacteria. By regrinding the concentrate particles down to 10 µm, bottom-up consortium, 500 ppm silver, and 3 g/L of coal, more than 97% of the copper from the Miduk chalcopyrite concentrate is recovered within 12 days. The final recovery of the control test without the microbes is 35%. The performance of the bottom-up method is significantly better than the top-down one. The moderate thermophiles have an important role in copper biomining. https://jme.shahroodut.ac.ir/article_2269_c2d710fc082a2194cdd82a3dd9af3db1.pdf