Dynamic coupling of ferrihydrite transformation and associated arsenic desorption/redistribution mediated by sulfate-reducing bacteria

Zhou，Wenjing1; Zhu，Huiyan1; Hu，Shiwen1; Zhang，Bowei1; Gao，Kun1; Dang，Zhi2; Liu，Chongxuan1

2024

10.1016/j.jes.2022.12.007

Journal of Environmental Sciences   Impact Factor & Quartile

1001-0742

1878-7320

Sulfate-reducing bacteria play an important role in the geochemistry of iron (oxyhydr)oxide and arsenic (As) in natural environments; however, the associated reaction processes are yet to be fully understood. In this study, batch experiments coupled with geochemical, spectroscopic, microscopic, and thermodynamic analyses were conducted to investigate the dynamic coupling of ferrihydrite transformation and the associated As desorption/redistribution mediated by Desulfovibrio vulgaris (D. vulgaris). The results indicated that D. vulgaris could induce ferrihydrite transformation via S-driven and direct reduction processes. In the absence of SO, D. vulgaris directly reduced ferrihydrite, and As desorption and re-sorption occurred simultaneously during the partial transformation of ferrihydrite to magnetite. The increase in SO loading promoted the S-driven reduction of ferrihydrite and accelerated the subsequent mineralogical transformation. In the low and medium SO treatments, ferrihydrite was completely transformed to a mixture of magnetite and mackinawite, which increased the fraction of As in the residual phase and stabilized As. In the high SO treatment, although the replacement of ferrihydrite by only mackinawite also increased the fraction of As in the residual phase, 22.1% of the total As was released into the solution due to the poor adsorption affinity of As to mackinawite and the conversion of As to As. The mechanisms of ferrihydrite reduction, mineralogy transformation, and As mobilization and redistribution mediated by sulfate-reducing bacteria are closely related to the surrounding SO loadings. These results advance our understanding of the biogeochemical behavior of Fe, S, and As, and are helpful for the risk assessment and remediation of As contamination.

Arsenic Ferrihydrite Redistribution Sulfate-reducing bacteria Transformation

English

First ; Corresponding

2-s2.0-85147798282

Scopus

1.State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control,School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China
2.The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters,Ministry of Education,South China University of Technology,Guangzhou,510006,China

Zhou，Wenjing,Zhu，Huiyan,Hu，Shiwen,et al. Dynamic coupling of ferrihydrite transformation and associated arsenic desorption/redistribution mediated by sulfate-reducing bacteria[J]. Journal of Environmental Sciences,2024,135:39-50.

Zhou，Wenjing.,Zhu，Huiyan.,Hu，Shiwen.,Zhang，Bowei.,Gao，Kun.,...&Liu，Chongxuan.(2024).Dynamic coupling of ferrihydrite transformation and associated arsenic desorption/redistribution mediated by sulfate-reducing bacteria.Journal of Environmental Sciences,135,39-50.

Zhou，Wenjing,et al."Dynamic coupling of ferrihydrite transformation and associated arsenic desorption/redistribution mediated by sulfate-reducing bacteria".Journal of Environmental Sciences 135(2024):39-50.