This study investigated the solid-phase Hg formed by reacting 0.005 or 0.01 M Hg(II) with 10 g/L mackinawite (FeS) as a function of pH in 0.2 M chloride solutions using X-ray diffraction (XRD), transmission electron microscopy (TEM), and extended X-ray absorption fine structure (EXAFS) analyses. Under all experimental conditions, XRD analysis showed formation of metacinnabar (β-HgS) as a bulk-phase sorption product, in agreement with the results from high angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) and selected area electron diffraction (SAED) in TEM analysis. HAADF-STEM and energy dispersive X-ray (EDX) analyses also suggested formation of Hg(II) surface precipitates. EXAFS analysis indicated that metacinnabar was the dominant product under most conditions, with Hg(II) chlorosulfide-like surface precipitates having increased contribution at lower Hg(II) concentration and higher pH. This finding is consistent with the results of desorption experiments using Hg(II)-complexing ligands. Considering the low solubility and high stability of metacinnabar, our results support the potential application of mackinawite for sequestering Hg(II) in anoxic environments.
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http://dx.doi.org/10.1021/es100808y | DOI Listing |
J Environ Manage
January 2025
Department of Sanitary Engineering, Faculty of Civil and Environmental Engineering, Gdańsk University of Technology, Poland; School of Civil, Environmental, and Architectural Engineering, College of Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea. Electronic address:
Population expansion, industrialization, urban development, and climate changes increased the water crisis in terms of drinking water availability. Among the various nanomaterials for nanoremediation towards water treatment, FeS-based nanocomposites have emerged as promising candidates in the adsorptive and photocatalytic removal of contaminants. This paper, therefore, evaluates the potential of FeS-based nanocomposites for environmental applications, more specifically the combined use of adsorption and photocatalysis.
View Article and Find Full Text PDFJ Hazard Mater
December 2024
Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, School of Ecology and Environment, Anhui Normal University, Wuhu 241002, China; Anhui Provincial Engineering Laboratory of Water and Soil Pollution Control and Remediation, Anhui Normal University, Wuhu 241002, China. Electronic address:
Iron reduction impacts the mobilization and thionation of diphenylarsinic acid (DPAA) in soil, but the contribution of crystalline and non-crystalline iron remains unknown. A paddy soil deficient in non-crystalline iron (P-Fe), crystalline and non-crystalline iron (P-Fe) were incubated with sulfate-plus-lactate, and the results were compared with paddy soil (P) in our previous study. For treatments without ferrous sulfide (FeS) precipitation, the solution-to-solid ratio (R) of DPAA increased slightly and dramatically with iron reduction, respectively, for P-Fe and P, suggesting that the reduction of non-crystalline iron contributes more to DPAA mobilization than crystalline iron.
View Article and Find Full Text PDFSmall
December 2024
Department of Pharmaceutical & Biological Engineering, School of Chemical Engineering, Sichuan University, Chengdu, 610065, China.
FeS-based nanomaterials are widely used in Fenton-like reaction of antibiotics degradation. However, the problems of poor stability and low reusability limit the catalytic efficiency. Herein, the study ingeniously introduced the g-CN into FeS to synthesize g-CN@biogenic FeS (CN-BF-1) nanocomposite with strong interaction of iron ions and "N-pots" by the mediation of sulfate reducing bacteria (SRB).
View Article and Find Full Text PDFEnviron Pollut
January 2025
Aix-Marseille University - Environmental Chemistry Laboratory (LCE), UMR 7376, 3 place Victor Hugo - Case 29, 13331, Marseille Cedex 3, France.
pH influences the reactivity of iron (II) minerals towards halogenated pollutants like hexachlorocyclohexanes (HCHs). To explore these incompletely understood interactions, we investigated the carbon isotope fractionation of the δ-HCH isomer during dehalogenation by iron sulfide at pHs spanning a pH range across slightly acidic to alkaline domains (5.8-9.
View Article and Find Full Text PDFJ Hazard Mater
December 2024
Key Laboratory of Groundwater Resources and Environment of Ministry of Education, College of New Energy and Environment, Jilin University, Changchun 130021, China; National and Local Joint Engineering Laboratory for Petrochemical Contaminated Site Control and Remediation Technology, Jilin University, Changchun 130021, China; Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun 130021, China. Electronic address:
The biogeochemical behavior downstream of the zero-valent iron permeable reactive barrier (ZVI-PRB) plays an enormous positive role in the remediation of contaminated-groundwater, but has been completely neglected for a long time. Therefore, this study conducted a 240-day SRB-enhanced ZVI-PRB column experiment, focusing on what exactly happens downstream of ZVI-PRB. Results show that biosulfidation of SRB inside ZVI-PRB prolonged the complete Cr(VI) removal longevity of ZVI-PRB from 38 days to at least 240 days.
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