The enhancement of chalcopyrite bioleaching with an enriched microbial community by acidified seawater was studied,and the enhancing mechanism was analyzed.The microbial community was enriched at the Dabaoshan mine si...The enhancement of chalcopyrite bioleaching with an enriched microbial community by acidified seawater was studied,and the enhancing mechanism was analyzed.The microbial community was enriched at the Dabaoshan mine site,and the treated ore sample had high concentrations of chalcopyrite and galena.The experimental results show that copper extraction from chalcopyrite with an enriched microbial community in seawater was promoted from 13.1%to 62.1%by acidification in comparison with that without acidification.Further analyses of the solutions,solid residues and microbial compositions by scanning electron microscopy,X-ray diffraction,Raman spectroscopy,Fourier transform infrared spectroscopy and 16 S rDNA sequencing revealed the promoting effects of acidified seawater.This acidification can increase the biodissolution of chalcopyrite to increase the concentration of iron ions and maintain the redox potential in the range of 360−410 mV.The latter produces an optimal redox environment conducive to chalcopyrite dissolution via Cu_(2)S.The adaptability of the microbial community to a high-salt environment is improved.Chloride ions at 580 mmol/L improve the leaching kinetics of chalcopyrite by increasing the porosity and noncrystallinity of the intermediate elemental sulfur.This study provides a promising way to bioleaching copper minerals using seawater for areas with freshwater shortages.展开更多
基金Project(2022YFC2105300)supported by the National Key Research and Development Program of ChinaProjects(41802038,51774342)supported by the National Natural Science Foundation of China。
文摘The enhancement of chalcopyrite bioleaching with an enriched microbial community by acidified seawater was studied,and the enhancing mechanism was analyzed.The microbial community was enriched at the Dabaoshan mine site,and the treated ore sample had high concentrations of chalcopyrite and galena.The experimental results show that copper extraction from chalcopyrite with an enriched microbial community in seawater was promoted from 13.1%to 62.1%by acidification in comparison with that without acidification.Further analyses of the solutions,solid residues and microbial compositions by scanning electron microscopy,X-ray diffraction,Raman spectroscopy,Fourier transform infrared spectroscopy and 16 S rDNA sequencing revealed the promoting effects of acidified seawater.This acidification can increase the biodissolution of chalcopyrite to increase the concentration of iron ions and maintain the redox potential in the range of 360−410 mV.The latter produces an optimal redox environment conducive to chalcopyrite dissolution via Cu_(2)S.The adaptability of the microbial community to a high-salt environment is improved.Chloride ions at 580 mmol/L improve the leaching kinetics of chalcopyrite by increasing the porosity and noncrystallinity of the intermediate elemental sulfur.This study provides a promising way to bioleaching copper minerals using seawater for areas with freshwater shortages.
