He Peng, Yang Quanliu, Gu Chunyao, Liu Mengfei, Li Penghui, Luo Ting, Chen Jiancheng, Chen Junwen, Zhu Jianyu, Gan Min
School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha, 410083, China.
Guizhou Academy of Tobacco Sciences, Guiyang, 550011, China.
Chemosphere. 2024 Sep;363:142955. doi: 10.1016/j.chemosphere.2024.142955. Epub 2024 Jul 26.
As one of the important microorganisms in the mining area, the role of iron-sulfur oxidizing microorganisms in antimony (element symbolized as Sb) migration and transformation in mining environments has been largely neglected for a long time. Therefore, the processes of the typical iron-sulfur oxidizing bacterium Acidithiobacillus ferrooxidans (A. ferrooxidans) and pyrite interaction coupled with the migration and transformation of Sb were investigated in this paper. The bio-oxidation process of pyrite by A. ferrooxidans not only accelerates the oxidation rate of Sb(III) to Sb(V) (62.93% of 10 mg L within 4 h), but also promotes the adsorption and precipitation of Sb (32.89 % of 10 mg L within 96 h), and changes in the dosage of minerals, Sb concentration, and pH value affect the conversion of Sb. The characterization results show that the interaction between A. ferrooxidans and pyrite produces a variety of reactive species, such as HO and •OH, resulting in the oxidation of Sb(III). In addition, A. ferrooxidans mediates the formation of stereotyped iron-sulfur secondary minerals that can act as a major driver of Sb (especially Sb(V)) adsorption or co-precipitation. This study contributes to the further understanding of the diversified biogeochemical processes of iron-sulfur oxidizing bacteria-iron-sulfur minerals-toxic metals in mining environments and provides ideas for the development of in-situ treatment technologies for Sb.
作为矿区重要的微生物之一，长期以来，铁硫氧化微生物在采矿环境中锑（元素符号为Sb）迁移转化中的作用在很大程度上被忽视。因此，本文研究了典型的铁硫氧化细菌氧化亚铁硫杆菌（A. ferrooxidans）与黄铁矿相互作用过程中锑的迁移转化。氧化亚铁硫杆菌对黄铁矿的生物氧化过程不仅加速了Sb(III)向Sb(V)的氧化速率（4小时内10 mg/L的62.93%），还促进了锑的吸附和沉淀（96小时内10 mg/L的32.89%），矿物用量、锑浓度和pH值的变化会影响锑的转化。表征结果表明，氧化亚铁硫杆菌与黄铁矿之间的相互作用产生了多种活性物种，如HO和•OH，导致Sb(III)的氧化。此外，氧化亚铁硫杆菌介导了定型铁硫次生矿物的形成，这些矿物可作为锑（尤其是Sb(V)）吸附或共沉淀的主要驱动力。本研究有助于进一步理解采矿环境中铁硫氧化细菌-铁硫矿物-有毒金属的多样化生物地球化学过程，并为锑的原位处理技术开发提供思路。
