Corrosion Characteristics of Typical Gangue Minerals in Biometallurgical Systems

Abstract

Electrochemical and shake flask tests were used to examine the corrosion characteristics of typical gangue minerals in biometallurgical systems and their impact on microbial communities. The results show that the solubility order of the three gangue minerals is feldspar, mica, and quartz in descending order. Their corrosion processes are mainly controlled by cathodic electron-donating processes. They are subjected to triple resistance, which is defined as solution-resistant, colloidal silica passivation, and iron precipitation (ferric hydroxide or jarosite passivation). Fe³⁺ and microorganisms both greatly improve the corrosion capacity of the system for the three gangue minerals. The community diversity may rise to 9.3, 8.6, and 4.4 times that of the initial HQ0211 strain, respectively, in the presence of feldspar, mica, and quartz.. The proportions of autotrophic microorganisms Leptospirillum, Sulfobacillus, and Acidiplasma decreased significantly, and the mixed trophic archaeon Ferroplasma and heterotrophic archaeon Cuniculiplasma became the dominant microorganisms in the system. Finally, the dissolution mechanism of gangue minerals in biometallurgical systems is discussed. The results enrich the theory of the gangue mineral corrosion process, which can lay a foundation for the effective regulation of biometallurgical processes.

Graphical Abstract