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Tadayon Y, Vantelon D, Gigault J, Dia A, Pattier M, Dutruch L, Davranche M. Rare earth elements interaction with iron-organic matter colloids as a control of the REE environmental dissemination. J Colloid Interface Sci 2024; 655:70-79. [PMID: 37925970 DOI: 10.1016/j.jcis.2023.10.110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 09/06/2023] [Accepted: 10/20/2023] [Indexed: 11/07/2023]
Abstract
Rare earth elements (REE) are highly sought after for advanced technology, in response concerns about their environmental impact have arisen. The mobility and transport of REEs are influenced by their binding to solid surfaces, particularly colloids. With the widespread occurrence of REEs and their potential increase due to climate change, there is growing interest in understanding colloids composed of organic matter (OM) and iron (Fe). The reactivity of these colloids depends on their structural organization and the availability of Fe phase and OM binding sites. The effect of pH on the binding and mobility of REEs in these colloids in response to structural modification of Fe-OM colloids was investigated. REEs are primarily bind to the OM component of Fe-OM colloids, and their mobility is controlled by the response of OM colloids and molecules to pH conditions. At pH 6, the solubilization of small organic colloids (<3 kDa) control the REE pattern and subsequent speciation and mobility. In contrast, at pH 4, Fe-OM colloids bind less amount of REE but aggregate to form a large network. While most REEs remain soluble, those bound to Fe-OM colloids are expected to be immobilized through settlement or trapping in soil and sediment pores. This study supports the idea that colloids control the REE speciation and subsequent dissemination. The findings are particularly relevant for assessing the fate and ecotoxicology of REE in response to changing environmental conditions and increasing REE concentration in natural systems.
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Affiliation(s)
- Yasaman Tadayon
- Univ. Rennes, CNRS, Géosciences Rennes, UMR 6118, F-35000 Rennes, France.
| | - Delphine Vantelon
- Synchrotron SOLEIL, L'orme des merisiers, Saint Aubin BP48, 91192 Gif sur Yvette Cedex, France
| | - Julien Gigault
- TAKUVIK CNRS/ULaval, UMI3376, Université Laval, Quebec City, QC, Canada
| | - Aline Dia
- Univ. Rennes, CNRS, Géosciences Rennes, UMR 6118, F-35000 Rennes, France
| | - Maxime Pattier
- Univ. Rennes, CNRS, Géosciences Rennes, UMR 6118, F-35000 Rennes, France
| | - Lionel Dutruch
- Univ. Rennes, CNRS, Géosciences Rennes, UMR 6118, F-35000 Rennes, France
| | - Mélanie Davranche
- Univ. Rennes, CNRS, Géosciences Rennes, UMR 6118, F-35000 Rennes, France
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2
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Yang B, Rashid S, Graham N, Li G, Yu W. In-depth study of the removal of Mn(II) by Fe(VI) treatment and the profound influence of NOM on floc formation and properties. Water Res 2023; 247:120840. [PMID: 37950954 DOI: 10.1016/j.watres.2023.120840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 10/24/2023] [Accepted: 11/04/2023] [Indexed: 11/13/2023]
Abstract
The presence of manganese(II) in drinking water sources poses a significant treatment difficulty for water utilities, thus necessitating the development of effective removal strategies. Treatment by Fe(VI), a combined oxidant and coagulant, has been identified as a potential green solution; however, its effectiveness is hampered by natural organic matter (NOM), and this underlying mechanism is not fully understood. Here, we investigated the inhibitory effect of three different types of NOM, representing terrestrial, aquatic, and microbial origins, on Mn(II) removal and floc growth during Fe(VI) coagulation. Results revealed that Fe(VI) coagulation effectively removes Mn(II), but NOM could inhibit its effectiveness by competing in oxidation reactions, forming NOM-Fe complexes, and altering floc aggregation. Humic acid was found to exhibit the strongest inhibition due to its unsaturated heterocyclic species that strongly bond to flocs and react with Fe(VI). For the first time, this study has presented a comprehensive elucidation of the atomic-level structure of Fe(VI) hydrolysis products by employing Extended X-ray Absorption Fine Structure Spectroscopy (EXAFS). Results demonstrated that NOM strengthened single-corner and double-corner coordination between FeO6 octahedrons that were consumed by Mn(II), resulting in an increased contribution of γ-FeOOH in the core-shell structure (γ-FeOOH shell and γ-F2O3 core), thereby inhibiting coagulation effects. Furthermore, NOM impeded the formation of stable manganite, resulting in more low-valence Mn(III) being incorporated in the form of an unstable intermediate. These findings provide a deeper understanding of the complex interplay between Fe coagulants, heavy metal pollution, and NOM in water treatment and offer insight into the limitations of Fe(VI) in practical applications.
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Affiliation(s)
- Bingqian Yang
- State Key Laboratory of Environmental Aquatic Chemistry, Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences (UCAS), Beijing 100049, China
| | - Sajid Rashid
- State Key Laboratory of Environmental Aquatic Chemistry, Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences (UCAS), Beijing 100049, China
| | - Nigel Graham
- Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Guibai Li
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, China
| | - Wenzheng Yu
- State Key Laboratory of Environmental Aquatic Chemistry, Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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3
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Huang X, Ding Y, Zhu N, Li L, Fang Q. Enhanced sequestration of uranium by coexisted lead and organic matter during ferrihydrite transformation. Chemosphere 2023; 341:140041. [PMID: 37660796 DOI: 10.1016/j.chemosphere.2023.140041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 08/30/2023] [Accepted: 08/31/2023] [Indexed: 09/05/2023]
Abstract
The dynamic reactions of uranium (U) with iron (Fe) minerals change its behaviors in soil environment, however, how the coexisted constituents in soil affect U sequestration and release on Fe minerals during the transformation remains unclear. Herein, coupled effects of lead (Pb) and dissolved organic matter (DOM) on U speciation and release kinetics during the catalytic transformations of ferrihydrite (Fh) by Fe(II) were investigated. Our results revealed that the coexistence of Pb and DOM significantly reduced U release and increased the immobilization of U during Fh transformation, which were attributed to the enhanced inhibition of Fh transformation, the declined release of DOM and the increased U(VI) reduction. Specifically, the presence of Pb increased the coprecipitation of condensed aromatics, polyphenols and phenols, and these molecules were preferentially maintained by Fe (oxyhydr)oxides. The sequestrated polyphenols and phenols could further facilitate U(VI) reduction to U(IV). Additionally, a higher Pb content in coprecipitates caused a slower U release, especially when DOM was present. Compared with Pb, the concentrations of the released U were significantly lower during the transformation. Our results contribute to predicting U sequestration and remediating U-contaminated soils.
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Affiliation(s)
- Xixian Huang
- School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, PR China; School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong, 510006, PR China
| | - Yang Ding
- School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, PR China; Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, 421001, PR China.
| | - Nengwu Zhu
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong, 510006, PR China
| | - Liuqin Li
- School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, PR China
| | - Qi Fang
- School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, PR China
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4
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Furcas F, Lothenbach B, Mundra S, Borca CN, Albert CC, Isgor OB, Huthwelker T, Angst UM. Transformation of 2-Line Ferrihydrite to Goethite at Alkaline pH. Environ Sci Technol 2023; 57:16097-16108. [PMID: 37822288 PMCID: PMC10603785 DOI: 10.1021/acs.est.3c05260] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 09/27/2023] [Accepted: 09/28/2023] [Indexed: 10/13/2023]
Abstract
The transformation of 2-line ferrihydrite to goethite from supersaturated solutions at alkaline pH ≥ 13.0 was studied using a combination of benchtop and advanced synchrotron techniques such as X-ray diffraction, thermogravimetric analysis, and X-ray absorption spectroscopy. In comparison to the transformation rates at acidic to mildly alkaline environments, the half-life, t1/2, of 2-line ferrihydrite reduces from several months at pH = 2.0, and approximately 15 days at pH = 10.0, to just under 5 h at pH = 14.0. The calculated-first order rate constants of transformation, k, increase exponentially with respect to the pH and follow the progression log10 k = log10 k0 + a·pH3. Simultaneous monitoring of the aqueous Fe(III) concentration via inductively coupled plasma optical emission spectroscopy demonstrates that (i) goethite likely precipitates from solution and (ii) its formation is rate-limited by the comparatively slow redissolution of 2-line ferrihydrite. The analysis presented can be used to estimate the transformation rate of naturally occurring 2-line ferrihydrite in aqueous electrolytes characteristic to mine and radioactive waste tailings as well as the formation of corrosion products in cementitious pore solutions.
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Affiliation(s)
- Fabio
E. Furcas
- Institute
for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
| | | | - Shishir Mundra
- Institute
for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
| | - Camelia N. Borca
- Swiss
Light Source, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | | | - O. Burkan Isgor
- School
of Civil and Construction Engineering, Oregon
State University, Corvallis, 97331 Oregon, United States
| | - Thomas Huthwelker
- Swiss
Light Source, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Ueli M. Angst
- Institute
for Building Materials, ETH Zürich, 8093 Zürich, Switzerland
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5
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Ding Y, Huang X, Zhang H, Ding D. Effects of dissolved organic matter molecules on the sequestration and stability of uranium during the transformation of Fe (oxyhydr)oxides. Water Res 2023; 229:119387. [PMID: 36459895 DOI: 10.1016/j.watres.2022.119387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 11/17/2022] [Accepted: 11/18/2022] [Indexed: 06/17/2023]
Abstract
Amorphous ferrihydrite (Fh) is abundant in aquatic environments and sediments, and often coprecipitates with dissolved organic matter (DOM) to form mineral-organic aggregates. The Fe(II)-catalyzed transformation of Fh to crystalline Fe (oxyhydr)oxides (e.g., goethite) can result in the changes of uranium (U) species, but the effects of DOM molecules on the sequestration and stability of U during Fe (oxyhydr)oxides transformation are poorly understood. In this study, the associations of DOM molecules with U during the coprecipitation of DOM with Fh were evaluated, and the effects of DOM molecules on the kinetics of U release during Fe (oxyhydr)oxides transformation were investigated using a combination of Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS), X-ray photoelectron spectroscopy (XPS), and kinetic experiments. FT-ICR-MS results indicated that, in addition to phenolic and polyphenolic compounds with higher O/C ratios, portions of phenolic compounds with lower O/C ratios and aliphatic compounds were also contributed to UO22+ binding when Fh coprecipitated with DOM. In comparison, phenolic and polyphenolic compounds with higher O/C ratios and condensed aromatics were preferentially retained on Fe (oxyhydr)oxides during the transformation. XPS results further suggested that the coprecipitated DOM molecules facilitated the reduction of U(VI) to U(IV) during the transformation, possibly through providing electrons or acting as electron shuttles. The kinetic experiment results indicated that the transformation processes accelerated U release from Fe (oxyhydr)oxides, but the coprecipitated DOM molecules slowed down U release. Our results contribute to understanding the behaviors of U and predicting the sequestration of U in the environment.
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Affiliation(s)
- Yang Ding
- Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China; School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan 421001, China
| | - Xixian Huang
- School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan 421001, China.
| | - Hui Zhang
- Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China; School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan 421001, China
| | - Dexin Ding
- Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China; School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan 421001, China.
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6
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ThomasArrigo LK, Notini L, Shuster J, Nydegger T, Vontobel S, Fischer S, Kappler A, Kretzschmar R. Mineral characterization and composition of Fe-rich flocs from wetlands of Iceland: Implications for Fe, C and trace element export. Sci Total Environ 2022; 816:151567. [PMID: 34762956 DOI: 10.1016/j.scitotenv.2021.151567] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 11/05/2021] [Accepted: 11/05/2021] [Indexed: 05/26/2023]
Abstract
In freshwater wetlands, redox interfaces characterized by circumneutral pH, steep gradients in O2, and a continual supply of Fe(II) form ecological niches favorable to microaerophilic iron(II) oxidizing bacteria (FeOB) and the formation of flocs; associations of (a)biotic mineral phases, microorganisms, and (microbially-derived) organic matter. On the volcanic island of Iceland, wetlands are replenished with Fe-rich surface-, ground- and springwater. Combined with extensive drainage of lowland wetlands, which forms artificial redox gradients, accumulations of bright orange (a)biotically-derived Fe-rich flocs are common features of Icelandic wetlands. These loosely consolidated flocs are easily mobilized, and, considering the proximity of Iceland's lowland wetlands to the coast, are likely to contribute to the suspended sediment load transported to coastal waters. To date, however, little is known regarding (Fe) mineral and elemental composition of the flocs. In this study, flocs from wetlands (n = 16) across Iceland were analyzed using X-ray diffraction and spectroscopic techniques (X-ray absorption and 57Fe Mössbauer) combined with chemical extractions and (electron) microscopy to comprehensively characterize floc mineral, elemental, and structural composition. All flocs were rich in Fe (229-414 mg/g), and floc Fe minerals comprised primarily ferrihydrite and nano-crystalline lepidocrocite, with a single floc sample containing nano-crystalline goethite. Floc mineralogy also included Fe in clay minerals and appreciable poorly-crystalline aluminosilicates, most likely allophane and/or imogolite. Microscopy images revealed that floc (bio)organics largely comprised mineral encrusted microbially-derived components (i.e. sheaths, stalks, and EPS) indicative of common FeOB Leptothrix spp. and Gallionella spp. Trace element contents in the flocs were in the low μg/g range, however nearly all trace elements were extracted with hydroxylamine hydrochloride. This finding suggests that the (a)biotic reductive dissolution of floc Fe minerals, plausibly driven by exposure to the varied geochemical conditions of coastal waters following floc mobilization, could lead to the release of associated trace elements. Thus, the flocs should be considered vectors for transport of Fe, organic carbon, and trace elements from Icelandic wetlands to coastal waters.
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Affiliation(s)
- Laurel K ThomasArrigo
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 16, CHN, CH-8092 Zürich, Switzerland.
| | - Luiza Notini
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 16, CHN, CH-8092 Zürich, Switzerland
| | - Jeremiah Shuster
- Tübingen Structural Microscopy Core Facility, Centre for Applied Geosciences (ZAG), University of Tübingen, Schnarrenbergstrasse 94-96, D-72076 Tübingen, Germany
| | - Tabea Nydegger
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 16, CHN, CH-8092 Zürich, Switzerland
| | - Sophie Vontobel
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 16, CHN, CH-8092 Zürich, Switzerland
| | - Stefan Fischer
- Tübingen Structural Microscopy Core Facility, Centre for Applied Geosciences (ZAG), University of Tübingen, Schnarrenbergstrasse 94-96, D-72076 Tübingen, Germany
| | - Andreas Kappler
- Geomicrobiology Group, Centre for Applied Geosciences (ZAG), University of Tübingen, Schnarrenbergstrasse 94-96, D-72076 Tübingen, Germany
| | - Ruben Kretzschmar
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 16, CHN, CH-8092 Zürich, Switzerland
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7
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Peng J, Fu F, Ye C, Tang B. Interaction between Se(IV) and fulvic acid and its impact on Se(IV) immobility in ferrihydrite-Se(IV) coprecipitates during aging. Environ Pollut 2022; 293:118552. [PMID: 34801618 DOI: 10.1016/j.envpol.2021.118552] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 11/15/2021] [Accepted: 11/17/2021] [Indexed: 06/13/2023]
Abstract
Selenium (Se) is regarded as a trace element for humans, but it is toxic in excess. In natural environments, the mobility of Se is dominantly controlled by the Se oxyanions with high solubility such as selenite (Se(IV)). Se(IV) is often associated with the omnipresent ferrihydrite and coexisting organic matter. However, there is little information on the dynamic interactions among Se(IV), fulvic acid, and ferrihydrite. This study investigated the influence of fulvic acid on ferrihydrite-Se(IV) coprecipitates (Fh-Se) transformation for 8 days and the subsequent behavior of Se(IV) at varied pH (5.0, 7.5, and 10.0). Results showed that fulvic acid had different effects on Fh-Se transformation at varied pH values. Fh-Se transformation was promoted by fulvic acid at initial pH 5.0 whereas it was inhibited at initial pH 10.0. Interestingly, at initial pH 7.5, Fh-Se transformation was promoted at a low C/Fe ratio while it was suppressed at a high C/Fe ratio. Besides, fulvic acid induced the generation of more extractable Se(IV) at initial pH 5.0 and more coprecipitated Se(IV) at initial pH 7.5 and blocked the release of Se(IV) at initial pH 10.0. Fulvic acid possibly interacted with Se(IV) via carboxyl complexation and weakened the inhibition of Se(IV) on Fh-Se transformation. Thus, fulvic acid increased the transformation rate of Fh-Se. These findings help to uncover the environmental behavior of Se(IV) and organic matter during ferrihydrite transformation.
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Affiliation(s)
- Jinlong Peng
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China
| | - Fenglian Fu
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China.
| | - Chujia Ye
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China
| | - Bing Tang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China
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8
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Darma A, Yang J, Bloem E, Możdżen K, Zandi P. Arsenic biotransformation and mobilization: the role of bacterial strains and other environmental variables. Environ Sci Pollut Res Int 2022; 29:1763-1787. [PMID: 34713399 DOI: 10.1007/s11356-021-17117-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 10/15/2021] [Indexed: 06/13/2023]
Abstract
Over several decades, arsenic (As) toxicity in the biosphere has affected different flora, fauna, and other environmental components. The majority of these problems are linked with As mobilization due to bacterial dissolution of As-bearing minerals and its transformation in other reservoirs such as soil, sediments, and ground water. Understanding the process, mechanism, and various bacterial species involved in these processes under the influence of some ecological variables greatly contributes to a better understanding of the fate and implications of As mobilization into the environments. This article summarizes the process, role, and various types of bacterial species involved in the transformation and mobilization of As. Furthermore, insight into how Fe(II) oxidation and resistance mechanisms such as methylation and detoxification against the toxic effect of As(III) was highlighted as a potential immobilization and remediation strategy in As-contaminated sites. Furthermore, the significance and comparative advantages of some useful analytical tools used in the evaluation, speciation, and analysis of As are discussed and how their in situ and ex situ applications support assessing As contamination in both laboratory and field settings. Nevertheless, additional research involving advanced molecular techniques is required to elaborate on the contribution of these bacterial consortia as a potential agronomic tool for reducing As availability, particularly in natural circumstances. Graphical abstract. Courtesy of conceptual model: Aminu Darma.
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Affiliation(s)
- Aminu Darma
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Jianjun Yang
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China.
| | - Elke Bloem
- Institute for Crop and Soil Science Julius Kühn-Institut (JKI), Federal Research Centre for Cultivated Plants, Bundesallee 69, 38116, Braunschweig, Germany
| | - Katarzyna Możdżen
- Institute of Biology, Pedagogical University of Krakow, Podchorążych 2 St, 30-084, Kraków, Poland
| | - Peiman Zandi
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
- International Faculty of Applied Technology, Yibin University, Yibin, 644000, People's Republic of China
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9
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Zhang Y, Li S, Sun J, Bostick BC, Zheng Y. Persistent arsenate-iron(iii) oxyhydroxide-organic matter nanoaggregates observed in coal. Environ Sci Nano 2021; 8:2964-2975. [PMID: 34950482 PMCID: PMC8691755 DOI: 10.1039/d1en00502b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Understanding how natural nanoaggregates of iron (Fe) and organic matter (OM), currently identified in organic rich soil or peat, interact with metals and metalloids is environmentally significant. Coal is also organic-rich and exemplifies anoxic sedimentary environments with Fe usually as pyrite and not oxides. Here, we analyze the local structure of Fe (6880-21 700 mg kg-1) and As (45-5680 mg kg-1) in representative Guizhou coal samples using X-ray absorption near-edge structure and extended X-ray absorption fine structure (XANES and EXAFS) to illustrate how Fe(iii) and As(v) are preserved in coal formed from reduced, organic-rich precursors. Arsenic XANES indicates that >80% of As exists as As(v) with <14% of As associated with sulfides in 5 Guizhou coal samples, confirming published but unexplained results. An As-Fe shell at 3.25-3.29 Å in the As EXAFS suggests that this As(v) is adsorbed on Fe(iii) oxyhydroxides as evidenced by Fe EXAFS in these coal samples. Significantly, lower Fe-Fe coordination numbers (CN) of 0.6-1.1 relative to those in 2-line ferrihydrite (CN = 1.6) and goethite (CN = 2.1) suggest that these Fe(iii) oxyhydroxides are likely Fe-OM nanoaggregates protected by OM encapsulation and adsorption of arsenate. Such structurally stabilized composites of As(v)-Fe(iii)-OM may be more widely distributed and allow oxidized As and Fe to persist in other organic-rich, reducing environments.
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Affiliation(s)
- Yinfeng Zhang
- Yunnan Key Laboratory of Plateau Wetland Conservation, Restoration and Ecological Services, College of Wetlands, Southwest Forestry University, Kunming, 650224, China
- State Key Lab of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Shehong Li
- State Key Lab of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Jing Sun
- State Key Lab of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Benjamin C Bostick
- Lamont-Doherty Earth Observatory, Columbia University, 61 Route 9W, Palisades, NY 10964, USA
| | - Yan Zheng
- 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
- Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
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10
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Whitaker AH, Austin RE, Holden KL, Jones JL, Michel FM, Peak D, Thompson A, Duckworth OW. The Structure of Natural Biogenic Iron (Oxyhydr)oxides Formed in Circumneutral pH Environments. Geochim Cosmochim Acta 2021; 308:237-255. [PMID: 34305159 PMCID: PMC8294128 DOI: 10.1016/j.gca.2021.05.059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Biogenic iron (Fe) (oxyhydr)oxides (BIOS) partially control the cycling of organic matter, nutrients, and pollutants in soils and water via sorption and redox reactions. Although recent studies have shown that the structure of BIOS resembles that of two-line ferrihydrite (2LFh), we lack detailed knowledge of the BIOS local coordination environment and structure required to understand the drivers of BIOS reactivity in redox active environments. Therefore, we used a combination of microscopy, scattering, and spectroscopic methods to elucidate the structure of BIOS sampled from a groundwater seep in North Carolina and compare them to 2LFh. We also simulated the effects of wet-dry cycles by varying sample preparation (e.g., freezing, flash freezing with freeze drying, freezing with freeze drying and oven drying). In general, the results show that both the long- and short-range ordering in BIOS are structurally distinct and notably more disordered than 2LFh. Our structure analysis, which utilized Fe K-edge X-ray absorption spectroscopy, Mössbauer spectroscopy, X-ray diffraction, and pair distribution function analyses, showed that the BIOS samples were more poorly ordered than 2LFh and intimately mixed with organic matter. Furthermore, pair distribution function analyses resulted in coherent scattering domains for the BIOS samples ranging from 12-18 Å, smaller than those of 2LFh (21-27 Å), consistent with reduced ordering. Additionally, Fe L-edge XAS indicated that the local coordination environment of 2LFh samples consisted of minor amounts of tetrahedral Fe(III), whereas BIOS were dominated by octahedral Fe(III), consistent with depletion of the sites due to small domain size and incorporation of impurities (e.g., organic C, Al, Si, P). Within sample sets, the frozen freeze dried and oven dried sample preparation increased the crystallinity of the 2LFh samples when compared to the frozen treatment, whereas the BIOS samples remained more poorly crystalline under all sample preparations. This research shows that BIOS formed in circumneutral pH waters are poorly ordered and more environmentally stable than 2LFh.
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Affiliation(s)
- Andrew H. Whitaker
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Robert E. Austin
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Kathryn L. Holden
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Jacob L. Jones
- Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - F. Marc Michel
- Department of Geosciences, Virginia Tech, Blacksburg, Virginia 24060, USA
| | - Derek Peak
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada
| | - Aaron Thompson
- Department of Crop and Soil Sciences, University of Georgia, Athens, Georgia 30602, USA
| | - Owen W. Duckworth
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, North Carolina 27695, USA
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11
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Glodowska M, Schneider M, Eiche E, Kontny A, Neumann T, Straub D, Berg M, Prommer H, Bostick BC, Nghiem AA, Kleindienst S, Kappler A. Fermentation, methanotrophy and methanogenesis influence sedimentary Fe and As dynamics in As-affected aquifers in Vietnam. Sci Total Environ 2021; 779:146501. [PMID: 34030262 DOI: 10.1016/j.scitotenv.2021.146501] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 02/24/2021] [Accepted: 03/11/2021] [Indexed: 06/12/2023]
Abstract
High arsenic (As) concentrations in groundwater are a worldwide problem threatening the health of millions of people. Microbial processes are central in the (trans)formation of the As-bearing ferric and ferrous minerals, and thus regulate dissolved As levels in many aquifers. Mineralogy, microbiology and dissolved As levels can vary sharply within aquifers, making high-resolution measurements particularly valuable in understanding the linkages between them. We conducted a high spatial resolution geomicrobiological study in combination with analysis of sediment chemistry and mineralogy in an alluvial aquifer system affected by geogenic As in the Red River delta in Vietnam. Microbial community analysis revealed a dominance of fermenters, methanogens and methanotrophs whereas sediment mineralogy along a 46 m deep core showed a diversity of Fe minerals including poorly crystalline Fe (II/III) and Fe(III) (oxyhydr)oxides such as goethite, hematite, and magnetite, but also the presence of Fe(II)-bearing carbonates and sulfides which likely formed as a result of microbially driven organic carbon (OC) degradation. A potential important role of methane (CH4) as electron donor for reductive Fe mineral (trans)formation was supported by the high abundance of Candidatus Methanoperedens, a known Fe(III)-reducing methanotroph. Overall, these results imply that OC turnover including fermentation, methanogenesis and CH4 oxidation are important mechanisms leading to Fe mineral (trans)formation, dissolution and precipitation, and thus indirectly affecting As mobility by changing the Fe-mineral inventory.
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Affiliation(s)
- Martyna Glodowska
- Geomicrobiology, Center for Applied Geosciences, University of Tübingen, Germany; Microbial Ecology, Center for Applied Geosciences, University of Tübingen, Germany; Department of Microbiology, IWWR, Radboud University, the Netherlands.
| | - Magnus Schneider
- Karlsruhe Institute of Technology, Institute of Applied Geosciences, Germany
| | - Elisabeth Eiche
- Karlsruhe Institute of Technology, Institute of Applied Geosciences, Germany
| | - Agnes Kontny
- Karlsruhe Institute of Technology, Institute of Applied Geosciences, Germany
| | - Thomas Neumann
- Technical University of Berlin, Institute for Applied Geosciences, Berlin, Germany
| | - Daniel Straub
- Microbial Ecology, Center for Applied Geosciences, University of Tübingen, Germany; Quantitative Biology Center (QBiC), University of Tübingen, Germany
| | - Michael Berg
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Henning Prommer
- School of Earth Sciences, University of Western Australia, Perth, WA, Australia; CSIRO Land and Water, Floreat, WA, Australia
| | | | | | - Sara Kleindienst
- Microbial Ecology, Center for Applied Geosciences, University of Tübingen, Germany
| | - Andreas Kappler
- Geomicrobiology, Center for Applied Geosciences, University of Tübingen, Germany
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12
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Wang HY, Göttlicher J, Byrne JM, Guo HM, Benning LG, Norra S. Vertical redox zones of Fe-S-As coupled mineralogy in the sediments of Hetao Basin - Constraints for groundwater As contamination. J Hazard Mater 2021; 408:124924. [PMID: 33385723 DOI: 10.1016/j.jhazmat.2020.124924] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 11/18/2020] [Accepted: 12/19/2020] [Indexed: 06/12/2023]
Abstract
The formation of iron-sulfur-arsenic (Fe-S-As) minerals during biogeochemical processes in As contaminated aquifers remains poorly understood despite their importance to understanding As release and transport in such systems. In this study, X-ray absorption and Mössbauer spectroscopies complemented by electron microscopy, and chemical extractions were used to examine vertical changes of As, Fe and S speciation for the example of sediments in the Hetao Basin. Reduction of Fe(III), As(V) and SO42- species were shown to co-occur in the aquifers. Iron oxides were observed to be predominantly goethite and hematite (36 - 12%) and appeared to decrease in abundance with depth. Furthermore, reduced As (including arsenite and As sulfides) and sulfur species (including S(-II), S(-I) and S0) increased from 16% to 76% and from 13% to 44%, respectively. Iron oxides were the major As carrier in the sediments, and the lower groundwater As concentration consists with less desorbable and reducible As in the sediments. The formation of As-Fe sulfides (e.g., As containing pyrite and greigite) induced by redox heterogeneities likely contribute to localized lower groundwater As concentrations. These results help to further elucidate the complex relationship between biogeochemical processes and minerals formation in As contaminated aquifers.
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Affiliation(s)
- H Y Wang
- Institute of Applied Geoscience, Working Group of Environmental Mineralogy and Environmental System Analysis, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany.
| | - J Göttlicher
- Institute of Photon Science and Synchrotron Radiation, Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen, Germany
| | - J M Byrne
- Geomicrobiology, Center for Applied Geosciences, University of Tübingen, 72074 Tübingen, Germany; Now: School of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol BS8 1RJ, United Kingdom
| | - H M Guo
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geoscience, 100083 Beijing, China
| | - L G Benning
- GFZ German Research Center for Geoscience, 14473 Potsdam, Germany; Department of Earth Sciences, Freie Universität Berlin, 12249 Berlin, Germany
| | - S Norra
- Institute of Applied Geoscience, Working Group of Environmental Mineralogy and Environmental System Analysis, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
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13
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Funnell NP, Fulford MF, Inoué S, Kletetschka K, Michel FM, Goodwin AL. Nanocomposite structure of two-line ferrihydrite powder from total scattering. Commun Chem 2020; 3:22. [PMID: 36703415 DOI: 10.1038/s42004-020-0269-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 02/04/2020] [Indexed: 01/29/2023] Open
Abstract
Ferrihydrite is one of the most important iron-containing minerals on Earth. Yet determination of its atomic-scale structure has been frustrated by its intrinsically poor crystallinity. The key difficulty is that physically-different models can appear consistent with the same experimental data. Using X-ray total scattering and a nancomposite reverse Monte Carlo approach, we evaluate the two principal contending models-one a multi-phase system without tetrahedral iron(III), and the other a single phase with tetrahedral iron(III). Our methodology is unique in considering explicitly the complex nanocomposite structure the material adopts: namely, crystalline domains embedded in a poorly-ordered matrix. The multi-phase model requires unphysical structural rearrangements to fit the data, whereas the single-phase model accounts for the data straightforwardly. Hence the latter provides the more accurate description of the short- and intermediate-range order of ferrihydrite. We discuss how this approach might allow experiment-driven (in)validation of complex models for important nanostructured phases beyond ferrihydrite.
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14
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Cai X, Wang P, Li Z, Li Y, Yin N, Du H, Cui Y. Mobilization and transformation of arsenic from ternary complex OM-Fe(III)-As(V) in the presence of As(V)-reducing bacteria. J Hazard Mater 2020; 381:120975. [PMID: 31445471 DOI: 10.1016/j.jhazmat.2019.120975] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 07/17/2019] [Accepted: 08/06/2019] [Indexed: 06/10/2023]
Abstract
Organic matter (OM) was proved to have a high affinity for arsenic (As) in the presence of ferric iron (Fe(III)), the formed ternary complex OM-Fe(III)-As(V) were frequently studied before; however, the mobilization and transformation of As from OM-Fe(III)-As(V) in the presence of As(V)-reducing bacteria remains unclear. Two different strains (Desulfitobacterium sp. DJ-3, Exiguobacterium sp. DJ-4) were incubated with OM-Fe(III)-As(V) to assess the biotransformation of As and Fe. Results showed that Desulfitobacterium sp. DJ-3 could substantially stimulate the reduction and release of OM-Fe complexed As(V) and resulted in notable As(III) release (30 mg/L). The linear combination fitting result of k3-weighted As K-edge EXAFS spectra showed that 56% of OM-Fe-As(V) was transformed to OM-Fe-As(III) after 144 h. Besides, strain DJ-3 could also reduce OM complexed Fe(III), which lead to the decomposition of ternary complex and the release of 11.8 mg/g Fe(II), this microbial Fe(III) reduction process has resulted in 11% more As liberation from OM-Fe(III)-As(V) than without bacteria. In contrast, Exiguobacterium sp. DJ-4 could only reduce free As(V) but cannot stimulate As release from the complex. Our study provides the first evidence for microbial As reduction and release from ternary complex OM-Fe(III)-As(V), which could be of great importance in As geochemical circulation.
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Affiliation(s)
- Xiaolin Cai
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Pengfei Wang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Zejiao Li
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Yan Li
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Naiyi Yin
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Huili Du
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Yanshan Cui
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China.
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15
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Field HR, Whitaker AH, Henson JA, Duckworth OW. Sorption of copper and phosphate to diverse biogenic iron (oxyhydr)oxide deposits. Sci Total Environ 2019; 697:134111. [PMID: 31487593 DOI: 10.1016/j.scitotenv.2019.134111] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 08/23/2019] [Accepted: 08/24/2019] [Indexed: 06/10/2023]
Abstract
Iron (Fe) transformations partially control the biogeochemical cycling of biologically and environmentally important elements, such as carbon (C), nitrogen (N), phosphorus (P), and trace metals. In marine and freshwater environments, iron oxidizing bacteria commonly promote the oxidation of ferrous iron (Fe(II)) at circumneutral oxic-anoxic interfaces, resulting in the formation of mineral-organic composites known as biogenic Fe(III) (oxyhydr)oxides (BIOS). Previous studies have examined the microbial ecology, composition, morphology, and sorption reactivity of BIOS. However, a broad survey of BIOS properties and sorption reactivity is lacking. To further explore these relationships, this study utilized X-ray absorption spectroscopy (XAS) to characterize the Fe mineral species, acid digestions and elemental analysis to determine composition, Brunauer-Emmett-Teller (BET) analysis to measure specific surface area, and copper (Cu) and phosphorus (P) adsorption experiments at concentrations designed to measure maximum sorption to evaluate reactivity of BIOS samples collected in lakes and streams of the North Carolina Piedmont. Sample composition varied widely, with Fe and C content ranging from 6.3 to 34% and 3.4-13%, respectively. XAS spectra were best fit with 42-100% poorly crystalline Fe (oxyhydr)oxides, with the remainder composed of crystalline Fe minerals and organic complexes. On a sorbent mass basis, Cu and P sorption varied by a factor of two and 15, respectively. Regression analyses reveal interrelationships between physicochemical properties, and suggest that differences in P binding are driven by sorption to Fe(III) (oxyhydr)oxide surfaces. In total, results suggest that the physical and chemical characteristics of organic and Fe(III) (oxyhydr)oxide phases in BIOS interplay to control the sorption of solutes, and thus influence nutrient and contaminant cycling in soil and natural waters.
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Affiliation(s)
- Hannah R Field
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620, USA; Department of Geological and Environmental Sciences at Appalachian State University, Boone, NC 28608-2067, USA
| | - Andrew H Whitaker
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620, USA
| | - Joshua A Henson
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620, USA
| | - Owen W Duckworth
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620, USA.
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16
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ThomasArrigo LK, Kaegi R, Kretzschmar R. Ferrihydrite Growth and Transformation in the Presence of Ferrous Iron and Model Organic Ligands. Environ Sci Technol 2019; 53:13636-13647. [PMID: 31718167 DOI: 10.1021/acs.est.9b03952] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Ferrihydrite (Fh) is a poorly crystalline Fe(III)-oxyhydroxide found in abundance in soils and sediments. With a high specific surface area and sorption capacity at circumneutral pH, ferrihydrite is an important player in the biogeochemical cycling of nutrients and trace elements in redox-dynamic environments. Under reducing conditions, exposure to Fe(II) induces mineral transformations in ferrihydrite; the extent and trajectory of which may be greatly influenced by organic matter (OM). However, natural OM is heterogeneous and comprises a range of molecular weights (MWs) and varied functional group compositions. To date, the impact that the chemical composition of the associated OM has on Fe(II)-catalyzed mineral transformations is not clear. To address this knowledge gap, we coprecipitated ferrihydrite with model organic ligands selected to cover a range of MWs (25 000-50 000 vs <200 Da) as well as carboxyl content (polygalacturonic acid (PGA) > citric acid (CA) > galacturonic acid (GA)). Coprecipitates (C:Fe ≈ 0.6) were reacted with 1 mM 57Fe(II) for 1 week at pH 7, with time-resolved solid-phase analysis (via X-ray diffraction, X-ray absorption spectroscopy, and electron microscopy) revealing that all ligands inhibited Fe(II)-catalyzed ferrihydrite mineral transformations and the formation of crystalline secondary mineral phases compared to a pure ferrihydrite. For carboxyl-rich coprecipitates (Fh-PGA and Fh-CA), mineral transformations were less inhibited than in the carboxyl poor Fh-GA, and a crystalline lepidocrocite "shell" was formed surrounding the residual ferrihydrite core. However, Fe isotope analysis revealed that all coprecipitates underwent near complete atom exchange. Collectively, our results highlight that ferrihydrite is indeed an active mineral phase in redox-dynamic environments, but that its stability under reducing conditions, and thus capacity for nutrient and trace element retention, depends on the chemical characteristic of the associated OM, specifically OM-induced changes in the particle surface charge and the distribution of organic functional groups.
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Affiliation(s)
- Laurel K ThomasArrigo
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science , ETH Zurich , Universitätstraße 16 , CHN, CH-8092 Zurich , Switzerland
| | - Ralf Kaegi
- Eawag , Swiss Federal Institute of Aquatic Science and Technology , Überlandstraße 133 , CH-8600 Dübendorf , Switzerland
| | - Ruben Kretzschmar
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science , ETH Zurich , Universitätstraße 16 , CHN, CH-8092 Zurich , Switzerland
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17
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Karimian N, Burton ED, Johnston SG, Hockmann K, Choppala G. Humic acid impacts antimony partitioning and speciation during iron(II)-induced ferrihydrite transformation. Sci Total Environ 2019; 683:399-410. [PMID: 31141743 DOI: 10.1016/j.scitotenv.2019.05.305] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 05/20/2019] [Accepted: 05/20/2019] [Indexed: 06/09/2023]
Abstract
The Fe(II)-induced transformation of ferrihydrite, a potent scavenger for antimony (Sb), can considerably influence Sb mobility in reducing soils, sediments and groundwater systems. In these environments, humic acids (HA) are prevalent, yet their influence on Sb behaviour during ferrihydrite transformation is poorly understood. In this study, we investigated the effect of HA on (1) Sb partitioning between solid, colloidal and dissolved phases and (2) Sb redox speciation during the Fe(II)-induced transformation of Sb(V)-bearing ferrihydrite at pH 6.0 and 8.0 and Fe(II) concentrations of 0, 1 and 10 mM. The results show that, at pH 8.0 and in the presence of 10 mM Fe(II), ferrihydrite was replaced by goethite, lepidocrocite and magnetite across a wide range of HA concentrations. At pH 6.0 in the 10 mM Fe(II) treatments, ferrihydrite transformed to mainly lepidocrocite and goethite in both HA-free and low HA treatments. In contrast, high HA concentrations retarded the rate and extent of ferrihydrite transformation at both pH 6.0 and 8.0 in the 1 mM Fe(II) treatments. Antimony K-edge XANES spectroscopy revealed up to 60% reduction of solid-phase Sb(V) to Sb(III), which corresponded with an increase in the PO43--extractable fraction of solid-phase Sb in HA- and Fe(II)-rich conditions at pH 8.0. In contrast to the observations at pH 8.0, minimal reduction of solid-phase Sb(V) was observed in the pH 6.0 treatments with the highest HA content, yet some reduction of Sb(V) occurred (~30-40%) at intermediate HA concentrations. Humic acid-rich conditions were also found to promote the formation of substantial amounts of colloidal Sb in the <0.45 μm to 3 kDa size range at both pH 6.0 and 8.0. Our results demonstrate that HA can exert an important control on the partitioning, mobility and speciation of Sb during Fe(II)-induced transformation of ferrihydrite in sub-surface environments.
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Affiliation(s)
- Niloofar Karimian
- Southern Cross GeoScience, Southern Cross University, Lismore, NSW 2480, Australia.
| | - Edward D Burton
- Southern Cross GeoScience, Southern Cross University, Lismore, NSW 2480, Australia
| | - Scott G Johnston
- Southern Cross GeoScience, Southern Cross University, Lismore, NSW 2480, Australia
| | - Kerstin Hockmann
- University of Bayreuth Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), Universitaetsstrasse 30, 95440 Bayreuth, Germany
| | - Girish Choppala
- Southern Cross GeoScience, Southern Cross University, Lismore, NSW 2480, Australia
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18
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Dublet G, Worms I, Frutschi M, Brown A, Zünd GC, Bartova B, Slaveykova VI, Bernier-Latmani R. Colloidal Size and Redox State of Uranium Species in the Porewater of a Pristine Mountain Wetland. Environ Sci Technol 2019; 53:9361-9369. [PMID: 31356746 DOI: 10.1021/acs.est.9b01417] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Uranium (U) speciation was investigated in anoxically preserved porewater samples of a natural mountain wetland in Gola di Lago, Ticino, Switzerland. U porewater concentrations ranged from less than 1 μg/L to tens of μg/L, challenging the available analytical approaches for U speciation in natural samples. Asymmetrical flow field-flow fractionation coupled with inductively coupled plasma mass spectrometry allowed the characterization of colloid populations and the determination of the size distribution of U species in the porewater. Most of the U was associated with three fractions: <0.3 kDa, likely including dissolved U and very small U colloids; a 1-3 kDa fraction containing humic-like organic compounds, dispersed Fe, and, to a small extent, Fe nanoparticles; and a third fraction (5-50 nm), containing a higher amount of Fe and a lower amount of organic matter and U relative to the 1-3 kDa fraction. The proportion of U associated with the 1-3 kDa colloids varied spatially and seasonally. Using anion exchange resins, we also found that a significant proportion of U occurs in its reduced form, U(IV). Tetravalent U was interpreted as occurring within the colloidal pool of U. This study suggests that U(IV) can occur as small (1-3 kDa), organic-rich, and thus potentially mobile colloidal species in naturally reducing wetland environments.
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Affiliation(s)
- Gabrielle Dublet
- Environmental Microbiology Laboratory (EML) , Ecole Polytechnique Federale de Lausanne (EPFL) , EPFL-ENAC-IIE-EML, Station 6 , CH-1015 Lausanne , Switzerland
- Department of Chemistry , University of Oslo , P.O. Box 1033, NO-0315 Oslo , Norway
| | - Isabelle Worms
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, School of Earth and Environmental Sciences, Faculty of Sciences , University of Geneva , Uni Carl Vogt, Bvd Carl-Vogt 66 , CH-1211 Geneva 4 , Switzerland
| | - Manon Frutschi
- Environmental Microbiology Laboratory (EML) , Ecole Polytechnique Federale de Lausanne (EPFL) , EPFL-ENAC-IIE-EML, Station 6 , CH-1015 Lausanne , Switzerland
| | - Ashley Brown
- Environmental Microbiology Laboratory (EML) , Ecole Polytechnique Federale de Lausanne (EPFL) , EPFL-ENAC-IIE-EML, Station 6 , CH-1015 Lausanne , Switzerland
| | - Giada C Zünd
- Environmental Microbiology Laboratory (EML) , Ecole Polytechnique Federale de Lausanne (EPFL) , EPFL-ENAC-IIE-EML, Station 6 , CH-1015 Lausanne , Switzerland
| | - Barbora Bartova
- Environmental Microbiology Laboratory (EML) , Ecole Polytechnique Federale de Lausanne (EPFL) , EPFL-ENAC-IIE-EML, Station 6 , CH-1015 Lausanne , Switzerland
| | - Vera I Slaveykova
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, School of Earth and Environmental Sciences, Faculty of Sciences , University of Geneva , Uni Carl Vogt, Bvd Carl-Vogt 66 , CH-1211 Geneva 4 , Switzerland
| | - Rizlan Bernier-Latmani
- Environmental Microbiology Laboratory (EML) , Ecole Polytechnique Federale de Lausanne (EPFL) , EPFL-ENAC-IIE-EML, Station 6 , CH-1015 Lausanne , Switzerland
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19
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Giannetta B, Zaccone C, Plaza C, Siebecker MG, Rovira P, Vischetti C, Sparks DL. The role of Fe(III) in soil organic matter stabilization in two size fractions having opposite features. Sci Total Environ 2019; 653:667-674. [PMID: 30759592 DOI: 10.1016/j.scitotenv.2018.10.361] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 10/09/2018] [Accepted: 10/27/2018] [Indexed: 06/09/2023]
Abstract
Soil organic matter (SOM) protection, stability and long-term accumulation are controlled by several factors, including sorption onto mineral surfaces. Iron (Fe) has been suggested as a key regulator of SOM stability, both in acidic conditions, where Fe(III) is soluble, and in near-neutral pH environments, where it precipitates as Fe(III) (hydr)oxides. The present study aimed to probe, by sorption/desorption experiments in which Fe was added to the system, the mechanisms controlling Fe(III)-mediated organic carbon (C) stabilization; fine silt and clay (FSi + Cl) and fine sand (FSa) SOM fractions of three soils under different land uses were tested. Fe(III) addition caused a decrease in the organic C remaining in solution after reaction, indicating an Fe-mediated organic C stabilization effect. This effect was two times larger for FSa than for FSi + Cl, the former fraction being characterized by both low specific surface area and high organic C content. The organic C retained in the solid phase after Fe-mediated stabilization has relatively low sensitivity to desorption. Moreover, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy indicated that Fe-mediated organic C stabilization can be mainly ascribed to the formation of complexes between carbohydrate OH functional groups and Fe oxides. These results demonstrate that the binding of labile SOM compounds to Fe(III) contributes to its preservation, and that the mechanisms involved (flocculation vs. coating) depend on the size fractions.
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Affiliation(s)
- Beatrice Giannetta
- Department of Agricultural, Food and Environmental Sciences, Polytechnic University of Marche, via Brecce Bianche 10, 60131 Ancona, Italy
| | - Claudio Zaccone
- Department of the Sciences of Agriculture, Food and Environment, University of Foggia, via Napoli 25, 71122 Foggia, Italy.
| | - César Plaza
- Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones Científicas, Serrano 115 bis, 28006 Madrid, Spain
| | - Matthew G Siebecker
- Delaware Environmental Institute, University of Delaware, Interdisciplinary Science and Engineering (ISE) Laboratory, 221 Academy Street, Newark, DE 19716, USA
| | - Pere Rovira
- Forest Sciences and Technology Center of Catalonia, Carretera St Llorenç de Morunys, km 2, 25280 Solsona, Spain
| | - Costantino Vischetti
- Department of Agricultural, Food and Environmental Sciences, Polytechnic University of Marche, via Brecce Bianche 10, 60131 Ancona, Italy
| | - Donald L Sparks
- Delaware Environmental Institute, University of Delaware, Interdisciplinary Science and Engineering (ISE) Laboratory, 221 Academy Street, Newark, DE 19716, USA; Department of Plant and Soil Sciences, University of Delaware, Interdisciplinary Science and Engineering (ISE) Laboratory, 221 Academy Street, Newark, DE 19716, USA
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20
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ThomasArrigo LK, Byrne JM, Kappler A, Kretzschmar R. Impact of Organic Matter on Iron(II)-Catalyzed Mineral Transformations in Ferrihydrite-Organic Matter Coprecipitates. Environ Sci Technol 2018; 52:12316-12326. [PMID: 30991468 DOI: 10.1021/acs.est.8b03206] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Poorly crystalline Fe(III) (oxyhydr)oxides like ferrihydrite are abundant in soils and sediments and are often associated with organic matter (OM) in the form of mineral-organic aggregates. Under anoxic conditions, interactions between aqueous Fe(II) and ferrihydrite lead to the formation of crystalline secondary minerals, like lepidocrocite, goethite, or magnetite. However, the extent to which Fe(II)-catalyzed mineral transformations are influenced by ferrihydrite-associated OM is not well understood. We therefore reacted ferrihydrite-PGA coprecipitates (PGA = polygalacturonic acid, C:Fe molar ratios = 0-2.5) and natural Fe-rich organic flocs (C:Fe molar ratio = 2.2) with 0.5-5.0 mM isotopically labeled 57Fe(II) at pH 7 for 5 weeks. Relying on the combination of stable Fe isotope tracers, a novel application of the PONKCS method to Rietveld fitting of X-ray diffraction (XRD) patterns, and 57Fe Mössbauer spectroscopy, we sought to follow the temporal evolution in Fe mineralogy and elucidate the fate of adsorbed 57Fe(II). At low C:Fe molar ratios (0-0.05), rapid oxidation of surface-adsorbed 57Fe(II) resulted in 57Fe-enriched crystalline minerals and nearly complete mineral transformation within days. With increasing OM content, the atom exchange between the added aqueous 57Fe(II) and Fe in the organic-rich solids still occurred; however, XRD analysis showed that crystalline mineral precipitation was strongly inhibited. For high OM-content materials (C:Fe ≥ 1.2), Mössbauer spectroscopy revealed up to 39% lepidocrocite in the final Fe(II)-reacted samples. Because lepidocrocite was not detectable by XRD, we suggest that the Mössbauer-detected lepidocrocite consisted of nanosized clusters with lepidocrocite-like local structure, similar to the lepidocrocite found in natural flocs. Collectively, our results demonstrate that the C content of ferrihydrite-OM coprecipitates strongly impacts the degree and pathways of Fe mineral transformations and iron atom exchange during reactions with aqueous Fe(II).
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Affiliation(s)
- Laurel K ThomasArrigo
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science , ETH Zurich , Universitätstrasse 16, CHN , CH-8092 Zurich , Switzerland
| | - James M Byrne
- Geomicrobiology Group, Centre for Applied Geosciences (ZAG) , University of Tübingen , Sigwartstrasse 10 , D-72076 Tübingen , Germany
| | - Andreas Kappler
- Geomicrobiology Group, Centre for Applied Geosciences (ZAG) , University of Tübingen , Sigwartstrasse 10 , D-72076 Tübingen , Germany
| | - Ruben Kretzschmar
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science , ETH Zurich , Universitätstrasse 16, CHN , CH-8092 Zurich , Switzerland
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21
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Usman M, Byrne JM, Chaudhary A, Orsetti S, Hanna K, Ruby C, Kappler A, Haderlein SB. Magnetite and Green Rust: Synthesis, Properties, and Environmental Applications of Mixed-Valent Iron Minerals. Chem Rev 2018; 118:3251-3304. [PMID: 29465223 DOI: 10.1021/acs.chemrev.7b00224] [Citation(s) in RCA: 174] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Mixed-valent iron [Fe(II)-Fe(III)] minerals such as magnetite and green rust have received a significant amount of attention over recent decades, especially in the environmental sciences. These mineral phases are intrinsic and essential parts of biogeochemical cycling of metals and organic carbon and play an important role regarding the mobility, toxicity, and redox transformation of organic and inorganic pollutants. The formation pathways, mineral properties, and applications of magnetite and green rust are currently active areas of research in geochemistry, environmental mineralogy, geomicrobiology, material sciences, environmental engineering, and environmental remediation. These aspects ultimately dictate the reactivity of magnetite and green rust in the environment, which has important consequences for the application of these mineral phases, for example in remediation strategies. In this review we discuss the properties, occurrence, formation by biotic as well as abiotic pathways, characterization techniques, and environmental applications of magnetite and green rust in the environment. The aim is to present a detailed overview of the key aspects related to these mineral phases which can be used as an important resource for researchers working in a diverse range of fields dealing with mixed-valent iron minerals.
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Affiliation(s)
- M Usman
- Environmental Mineralogy, Center for Applied Geosciences , University of Tübingen , 72074 Tübingen , Germany.,Institute of Soil and Environmental Sciences , University of Agriculture , Faisalabad 38040 , Pakistan
| | - J M Byrne
- Geomicrobiology, Center for Applied Geosciences , University of Tübingen , 72074 Tübingen , Germany
| | - A Chaudhary
- Environmental Mineralogy, Center for Applied Geosciences , University of Tübingen , 72074 Tübingen , Germany.,Department of Environmental Science and Engineering , Government College University Faisalabad 38000 , Pakistan
| | - S Orsetti
- Environmental Mineralogy, Center for Applied Geosciences , University of Tübingen , 72074 Tübingen , Germany
| | - K Hanna
- Univ Rennes, École Nationale Supérieure de Chimie de Rennes , CNRS, ISCR - UMR6226 , F-35000 Rennes , France
| | - C Ruby
- Laboratoire de Chimie Physique et Microbiologie pour l'Environnement , UMR 7564 CNRS-Université de Lorraine , 54600 Villers-Lès-Nancy , France
| | - A Kappler
- Geomicrobiology, Center for Applied Geosciences , University of Tübingen , 72074 Tübingen , Germany
| | - S B Haderlein
- Environmental Mineralogy, Center for Applied Geosciences , University of Tübingen , 72074 Tübingen , Germany
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22
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Reithmaier GMS, Knorr KH, Arnhold S, Planer-Friedrich B, Schaller J. Enhanced silicon availability leads to increased methane production, nutrient and toxicant mobility in peatlands. Sci Rep 2017; 7:8728. [PMID: 28821870 PMCID: PMC5562759 DOI: 10.1038/s41598-017-09130-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 07/13/2017] [Indexed: 01/15/2023] Open
Abstract
Peatlands perform important ecosystem functions, such as carbon storage and nutrient retention, which are affected, among other factors, by vegetation and peat decomposition. The availability of silicon (Si) in peatlands differs strongly, ranging from <1 to >25 mg L−1. Since decomposition of organic material was recently shown to be accelerated by Si, the aim of this study was to examine how Si influences decomposition of carbon and nutrient and toxicant mobilization in peatlands. We selected a fen site in Northern Bavaria with naturally bioavailable Si pore water concentrations of 5 mg/L and conducted a Si addition experiment. At a fourfold higher Si availability, dissolved organic carbon, carbon dioxide, and methane concentrations increased significantly. Furthermore, dissolved nitrogen, phosphorus, iron, manganese, cobalt, zinc, and arsenic concentrations were significantly higher under high Si availability. This enhanced mobilization may result from Si competing for binding sites but also from stronger reducing conditions, caused by accelerated respiration. The stronger reducing conditions also increased reduction of arsenate to arsenite and thus the mobility of this toxicant. Hence, higher Si availability is suggested to decrease carbon storage and increase nutrient and toxicant mobility in peatland ecosystems.
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Affiliation(s)
- Gloria-Maria Susanne Reithmaier
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, Universitätsstraße 30, 95447, Bayreuth, Germany
| | - Klaus-Holger Knorr
- Ecohydrology and Biogeochemistry Group, Institute of Landscape Ecology, University of Münster, Heisenbergstr. 2, 48149, Münster, Germany
| | - Sebastian Arnhold
- Ecological Services, Department of Earth Sciences, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, Universitätsstraße 30, 95440, Bayreuth, Germany
| | - Britta Planer-Friedrich
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, Universitätsstraße 30, 95447, Bayreuth, Germany
| | - Jörg Schaller
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, Universitätsstraße 30, 95447, Bayreuth, Germany.
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Situm A, Rahman MA, Allen N, Kabengi N, Al-Abadleh HA. ATR-FTIR and Flow Microcalorimetry Studies on the Initial Binding Kinetics of Arsenicals at the Organic–Hematite Interface. J Phys Chem A 2017; 121:5569-5579. [DOI: 10.1021/acs.jpca.7b03426] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Arthur Situm
- Department
of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON N2L 3C5, Canada
| | - Mohammad A. Rahman
- Department
of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON N2L 3C5, Canada
| | | | | | - Hind A. Al-Abadleh
- Department
of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON N2L 3C5, Canada
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Abstract
The biotransformation of arsenic is highly relevant to the arsenic biogeochemical cycle. Identification of the molecular details of microbial pathways of arsenic biotransformation coupled with analyses of microbial communities by meta-omics can provide insights into detailed aspects of the complexities of this biocycle. Arsenic transformations couple to other biogeochemical cycles, and to the fate of both nutrients and other toxic environmental contaminants. Microbial redox metabolism of iron, carbon, sulfur, and nitrogen affects the redox and bioavailability of arsenic species. In this critical review we illustrate the biogeochemical processes and genes involved in arsenic biotransformations. We discuss how current and future metagenomic-, metatranscriptomic-, metaproteomic-, and metabolomic-based methods will help to decipher individual microbial arsenic transformation processes, and their connections to other biogeochemical cycle. These insights will allow future use of microbial metabolic capabilities for new biotechnological solutions to environmental problems. To understand the complex nature of inorganic and organic arsenic species and the fate of environmental arsenic will require integrating systematic approaches with biogeochemical modeling. Finally, from the lessons learned from these studies of arsenic biogeochemistry, we will be able to predict how the environment changes arsenic, and, in response, how arsenic biotransformations change the environment.
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Affiliation(s)
- Yong-Guan Zhu
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Corresponding Author: Phone: +86(0)592 6190997; fax: +86(0)592 6190977;
| | - Xi-Mei Xue
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Andreas Kappler
- Geomicrobiology, Center for Applied Geosciences, University of Tübingen, Tübingen 72076, Germany
| | - Barry P Rosen
- Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, Florida 33199, United States
| | - Andrew A Meharg
- Institute for Global Food Security, Queen’s University Belfast, Belfast BT9 5HN, United Kingdom
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ThomasArrigo LK, Mikutta C, Byrne J, Kappler A, Kretzschmar R. Iron(II)-Catalyzed Iron Atom Exchange and Mineralogical Changes in Iron-rich Organic Freshwater Flocs: An Iron Isotope Tracer Study. Environ Sci Technol 2017; 51:6897-6907. [PMID: 28590131 DOI: 10.1021/acs.est.7b01495] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In freshwater wetlands, organic flocs are often found enriched in trace metal(loid)s associated with poorly crystalline Fe(III)-(oxyhydr)oxides. Under reducing conditions, flocs may become exposed to aqueous Fe(II), triggering Fe(II)-catalyzed mineral transformations and trace metal(loid) release. In this study, pure ferrihydrite, a synthetic ferrihydrite-polygalacturonic acid coprecipitate (16.7 wt % C), and As- (1280 and 1230 mg/kg) and organic matter (OM)-rich (18.1 and 21.8 wt % C) freshwater flocs dominated by ferrihydrite and nanocrystalline lepidocrocite were reacted with an isotopically enriched 57Fe(II) solution (0.1 or 1.0 mM Fe(II)) at pH 5.5 and 7. Using a combination of wet chemistry, Fe isotope analysis, X-ray absorption spectroscopy (XAS), 57Fe Mössbauer spectroscopy and X-ray diffraction, we followed the Fe atom exchange kinetics and secondary mineral formation over 1 week. When reacted with Fe(II) at pH 7, pure ferrihydrite exhibited rapid Fe atom exchange at both Fe(II) concentrations, reaching 76 and 89% atom exchange in experiments with 0.1 and 1 mM Fe(II), respectively. XAS data revealed that it transformed into goethite (21%) at the lower Fe(II) concentration and into lepidocrocite (73%) and goethite (27%) at the higher Fe(II) concentration. Despite smaller Fe mineral particles in the coprecipitate and flocs as compared to pure ferrihydrite (inferred from Mössbauer-derived blocking temperatures), these samples showed reduced Fe atom exchange (9-30% at pH 7) and inhibited secondary mineral formation. No release of As was recorded for Fe(II)-reacted flocs. Our findings indicate that carbohydrate-rich OM in flocs stabilizes poorly crystalline Fe minerals against Fe(II)-catalyzed transformation by surface-site blockage and/or organic Fe(II) complexation. This hinders the extent of Fe atom exchange at mineral surfaces and secondary mineral formation, which may consequently impair Fe(II)-activated trace metal(loid) release. Thus, under short-term Fe(III)-reducing conditions facilitating the fast attainment of solid-solution equilibria (e.g., in stagnant waters), Fe-rich freshwater flocs are expected to remain an effective sink for trace elements.
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Affiliation(s)
- Laurel K ThomasArrigo
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, CHN, ETH Zurich , Universitätstrasse 16, CH-8092 Zurich, Switzerland
| | - Christian Mikutta
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, CHN, ETH Zurich , Universitätstrasse 16, CH-8092 Zurich, Switzerland
| | - James Byrne
- Geomicrobiology Group, Centre for Applied Geosciences (ZAG), University of Tübingen , Sigwartstrasse 10, D-72076, Tübingen, Germany
| | - Andreas Kappler
- Geomicrobiology Group, Centre for Applied Geosciences (ZAG), University of Tübingen , Sigwartstrasse 10, D-72076, Tübingen, Germany
| | - Ruben Kretzschmar
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, CHN, ETH Zurich , Universitätstrasse 16, CH-8092 Zurich, Switzerland
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Zhang X, Wu M, Dong H, Li H, Pan B. Simultaneous Oxidation and Sequestration of As(III) from Water by Using Redox Polymer-Based Fe(III) Oxide Nanocomposite. Environ Sci Technol 2017; 51:6326-6334. [PMID: 28499085 DOI: 10.1021/acs.est.7b00724] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Water decontamination from As(III) is an urgent but still challenging task. Herein, we fabricated a bifunctional nanocomposite HFO@PS-Cl for highly efficient removal of As(III), with active chlorine covalently binding spherical polystyrene host for in situ oxidation of As(III) to As(V), and Fe(III) hydroxide (HFO) nanoparticles (NPs) embedded inside for specific As(V) removal. HFO@PS-Cl could work effectively in a wide pH range (5-9), and other substances like sulfate, chloride, bicarbonate, silicate, and humic acid exert insignificant effect on As(III) removal. As(III) sequestration is realized via two pathways, that is, oxidation to As(V) by the active chlorine followed by specific As(V) adsorption onto HFO NPs, and As(III) adsorption onto HFO NPs followed by oxidation to As(V). The exhausted HFO@PS-Cl could be refreshed for cyclic runs with insignificant capacity loss by the combined regeneration strategy, that is, alkaline solution to rinse the adsorbed As(V) and NaClO solution to renew the host oxidation capability. In addition, fixed-bed experiments demonstrated that the HFO@PS-Cl column could generate >1760 bed volume (BV) effluent from a synthetic As(III)-containing groundwater to meet the drinking water standard (<10 μg As/L), whereas other two HFO nanocomposites, HFO@PS-N and HFO@D201 could only generate 450 and 600 BV effluents under otherwise identical conditions.
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Affiliation(s)
- Xiaolin Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210023, P.R. China
- Research Center for Environmental Nanotechnology (ReCENT), Nanjing University , Nanjing 210023, China
| | - Mengfei Wu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210023, P.R. China
| | - Hao Dong
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210023, P.R. China
| | - Hongchao Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210023, P.R. China
| | - Bingcai Pan
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210023, P.R. China
- Research Center for Environmental Nanotechnology (ReCENT), Nanjing University , Nanjing 210023, China
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Catrouillet C, Davranche M, Dia A, Bouhnik-Le Coz M, Demangeat E, Gruau G. Does As(III) interact with Fe(II), Fe(III) and organic matter through ternary complexes? J Colloid Interface Sci 2016; 470:153-161. [DOI: 10.1016/j.jcis.2016.02.047] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 02/18/2016] [Accepted: 02/18/2016] [Indexed: 11/27/2022]
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28
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Abstract
Peatlands have received significant atmospheric inputs of As and S since the onset of the Industrial Revolution, but the effect of S deposition on the fate of As is largely unknown. It may encompass the formation of As sulfides and organosulfur-bound As, or the indirect stimulation of As biotransformation processes, which are presently not considered as important As immobilization pathways in wetlands. To investigate the immobilization mechanisms of anthropogenically derived As in peatlands subjected to long-term atmospheric pollution, we explored the solid-phase speciation of As, Fe, and S in English peat bogs by X-ray absorption spectroscopy. Additionally, we analyzed the speciation of As in pore- and streamwaters. Linear combination fits of extended X-ray absorption fine structure (EXAFS) data imply that 62-100% (average: 82%) of solid-phase As (Astot: 9-92 mg/kg) was present as organic As(V) and As(III). In agreement with appreciable concentrations of organoarsenicals in surface waters (pH: 4.0-4.4, Eh: 165-190 mV, average Astot: 1.5-129 μg/L), our findings reveal extensive biotransformation of atmospheric As and the enrichment of organoarsenicals in the peat, suggesting that the importance of organometal(loid)s in wetlands subjected to prolonged air pollution is higher than previously assumed.
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Affiliation(s)
- Christian Mikutta
- Section for Environmental Chemistry and Physics, Department of Plant and Environmental Sciences, University of Copenhagen , DK-1871 Frederiksberg C, Denmark
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, CHN, ETH Zurich , 8092 Zurich, Switzerland
| | - James J Rothwell
- Upland Environments Research Unit, Geography, School of Environment, Education and Development, The University of Manchester , Manchester M13 9PL, U.K
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ThomasArrigo LK, Mikutta C, Lohmayer R, Planer-Friedrich B, Kretzschmar R. Sulfidization of Organic Freshwater Flocs from a Minerotrophic Peatland: Speciation Changes of Iron, Sulfur, and Arsenic. Environ Sci Technol 2016; 50:3607-3616. [PMID: 26967672 DOI: 10.1021/acs.est.5b05791] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Iron-rich organic flocs are frequently observed in surface waters of wetlands and show a high affinity for trace metal(loid)s. Under low-flow stream conditions, flocs may settle, become buried, and eventually be subjected to reducing conditions facilitating trace metal(loid) release. In this study, we reacted freshwater flocs (704-1280 mg As/kg) from a minerotrophic peatland (Gola di Lago, Switzerland) with sulfide (5.2 mM, S(-II)spike/Fe = 0.75-1.62 mol/mol) at neutral pH and studied the speciation changes of Fe, S, and As at 25 ± 1 °C over 1 week through a combination of synchrotron X-ray techniques and wet-chemical analyses. Sulfidization of floc ferrihydrite and nanocrystalline lepidocrocite caused the rapid formation of mackinawite (52-81% of Fesolid at day 7) as well as solid-phase associated S(0) and polysulfides. Ferrihydrite was preferentially reduced over lepidocrocite, although neoformation of lepidocrocite from ferrihydrite could not be excluded. Sulfide-reacted flocs contained primarily arsenate (47-72%) which preferentially adsorbed to Fe(III)-(oxyhydr)oxides, despite abundant mackinawite precipitation. At higher S(-II)spike/Fe molar ratios (≥1.0), the formation of an orpiment-like phase accounted for up to 35% of solid-phase As. Despite Fe and As sulfide precipitation and the presence of residual Fe(III)-(oxyhydr)oxides, mobilization of As was recorded in all samples (Asaq = 0.45-7.0 μM at 7 days). Aqueous As speciation analyses documented the formation of thioarsenates contributing up to 33% of Asaq. Our findings show that freshwater flocs from the Gola di Lago peatland may become a source of As under sulfate-reducing conditions and emphasize the pivotal role Fe-rich organic freshwater flocs play in trace metal(loid) cycling in S-rich wetlands characterized by oscillating redox conditions.
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Affiliation(s)
- Laurel K ThomasArrigo
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich , 8092 Zurich, Switzerland
| | - Christian Mikutta
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich , 8092 Zurich, Switzerland
- Section for Environmental Chemistry and Physics, Department of Plant and Environmental Sciences, University of Copenhagen , DK-1871 Frederiksberg C, Denmark
| | - Regina Lohmayer
- Department of Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), Bayreuth University , 95440 Bayreuth, Germany
| | - Britta Planer-Friedrich
- Department of Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), Bayreuth University , 95440 Bayreuth, Germany
| | - Ruben Kretzschmar
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich , 8092 Zurich, Switzerland
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