Influence of Biological and Environmental Factors on Leaching Efficiency during Chalcopyrite Bioleaching Process

In the bioleaching process, many factors in ore, water and sediments are important contributors as driving forces to improve leaching efficiency. In this study, FeSO₄·7H₂O and S⁰ as energy substrates were added to an oxide-rich, low-grade copper ore to explore the influence of biological and environmental factors on leaching efficiency. Mantel test results showed that the leaching rate was significantly correlated with biological and environmental factors with r values of 0.78 and 0.63 respectively, indicating that influence of biological factors were more significant. It cannot be ignored that environmental factors were important to construct the microbial community. Real-time quantification polymerase chain reaction (RT-qPCR) showed that the dominant and minor species were A. caldus and A. ferrooxidans. Canonical correspondence analysis (CCA) made it clear that pH and ferrous concentration were crucial for shaping microbial community. All results are of great significant to gain the optimal leaching condition on Zambia oxide-rich, low-grade copper ore.