Modified 9K Medium for Ore Bioleaching

Bioleaching applications with Acidithiobacillus ferrooxidans (A.f) have shown significant progress in recent years. Before being used in bioleaching applications, bacterial isolation processes must be performed and they must be provided to reach sufficient purity, activity, and population. For this, mediums are prepared by using various nutrient mixtures in different ratios. In this study, it was tried to obtain a modified medium that could be an alternative to the 9K medium of Silverman and Lundgren. At the same time, bacterial growth rates and Fe oxidation rates were investigated. During the modification process, KH2PO4 was used instead of K2HPO4, and its effects on bacterial growth were investigated by increasing the amount of FeSO4.7H2O. The experiments were conducted in 250 mL shaken flasks for 16 days in a continuous incubator system. In the experiments, bacterial growth and Fe oxidation were investigated by analyzing ferric ion concentration in specific periods and observing the color change of the solution. At the end of the experiments, it was determined that the highest iron oxidation efficiency, the lowest acid consumption and the best bacterial growth were in Medium 6 (0.1 g/L FeSO47H2O, non-KH2PO4).