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ThomasArrigo LK, Notini L, Vontobel S, Bouchet S, Nydegger T, Kretzschmar R. Emerging investigator series: Coprecipitation with glucuronic acid limits reductive dissolution and transformation of ferrihydrite in an anoxic soil. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2024. [PMID: 39051944 DOI: 10.1039/d4em00238e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/27/2024]
Abstract
Ferrihydrite, a poorly crystalline Fe(III)-oxyhydroxide, is abundant in soils and is often found associated with organic matter. Model studies consistently show that in the presence of aqueous Fe(II), organic carbon (OC)-associated ferrihydrite undergoes less transformation than OC-free ferrihydrite. Yet, these findings contrast microbial reductive dissolution studies in which the OC promotes the reductive dissolution of Fe(III) in ferrihydrite and leads to the release of associated OC. To shed light on these complex processes, we quantified the extent of reductive dissolution and transformation of native Fe minerals and added ferrihydrite in anoxic soil incubations where pure 57Fe-ferrihydrite (57Fh), pure 57Fe-ferrihydrite plus dissolved glucuronic acid (57Fh + GluCaq), a 57Fe-ferrihydrite-13C-glucuronic acid coprecipitate (57Fh13GluC), or only dissolved glucuronic acid (13GluCaq) were added. By tracking the transformation of the 57Fe-ferrihydrite in the solid phase with Mössbauer spectroscopy together with analysis of the iron isotope composition of the aqueous phase and chemical extractions with inductively coupled plasma-mass spectrometry, we show that the pure 57Fe-ferrihydrite underwent more reductive dissolution and transformation than the coprecipitated 57Fe-ferrihydrite when identical amounts of glucuronic acid were provided (57Fh + GluCaqversus57Fh13GluC treatments). In the absence of glucuronic acid, the pure 57Fe-ferrihydrite underwent the least reductive dissolution and transformation (57Fh). Comparing all treatments, the overall extent of Fe(III) reduction, including the added and native Fe minerals, determined with X-ray absorption spectroscopy, was highest in the 57Fh + GluCaq treatment. Collectively, our results suggest that the limited bioavailability of the coprecipitated OC restricts not only the reductive dissolution of the coprecipitated mineral, but it also limits the enhanced reduction of native soil Fe(III) minerals.
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Affiliation(s)
- Laurel K ThomasArrigo
- Environmental Chemistry Group, Institute of Chemistry, University of Neuchâtel, Avenue de Bellevaux 51, CH-2000, Neuchâtel, Switzerland.
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 16, CHN, CH-8092 Zurich, Switzerland
| | - Luiza Notini
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 16, CHN, CH-8092 Zurich, Switzerland
| | - Sophie Vontobel
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 16, CHN, CH-8092 Zurich, Switzerland
| | - Sylvain Bouchet
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 16, CHN, CH-8092 Zurich, Switzerland
| | - Tabea Nydegger
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 16, CHN, CH-8092 Zurich, 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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2
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Barron A, Jamieson J, Colombani N, Bostick BC, Ortega-Tong P, Sbarbati C, Barbieri M, Petitta M, Prommer H. Model-Based Analysis of Arsenic Retention by Stimulated Iron Mineral Transformation under Coastal Aquifer Conditions. ACS ES&T WATER 2024; 4:2944-2956. [PMID: 39005241 PMCID: PMC11242918 DOI: 10.1021/acsestwater.4c00134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
A multitude of geochemical processes control the aqueous concentration and transport properties of trace metal contaminants such as arsenic (As) in groundwater environments. Effective As remediation, especially under reducing conditions, has remained a significant challenge. Fe(II) nitrate treatments are a promising option for As immobilization but require optimization to be most effective. Here, we develop a process-based numerical modeling framework to provide an in-depth understanding of the geochemical mechanisms controlling the response of As-contaminated sediments to Fe(II) nitrate treatment. The analyzed data sets included time series from two batch experiments (control vs treatment) and effluent concentrations from a flow-through column experiment. The reaction network incorporates a mixture of homogeneous and heterogeneous reactions affecting Fe redox chemistry. Modeling revealed that the precipitation of the Fe treatment caused a rapid pH decline, which then triggered multiple heterogeneous buffering processes. The model quantifies key processes for effective remediation, including the transfer of aqueous As to adsorbed As and the transformation of Fe minerals, which act as sorption hosts, from amorphous to more stable phases. The developed model provides the basis for predictions of the remedial benefits of Fe(II) nitrate treatments under varying geochemical and hydrogeological conditions, particularly in high-As coastal environments.
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Affiliation(s)
- Alyssa Barron
- School of Earth Sciences, University of Western Australia, Crawley 6009 WA, Australia
| | | | | | - Benjamin C Bostick
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York 10964, United States
| | - Pablo Ortega-Tong
- School of Earth Sciences, University of Western Australia, Crawley 6009 WA, Australia; Intera Inc., Perth 6000 WA, Australia
| | - Chiara Sbarbati
- Dept. of Ecological and Biological Sciences, University of Tuscia, Viterbo 01100, Italy
| | - Maurizio Barbieri
- Dept. of Earth Sciences, "Sapienza" University of Roma, Roma 00185, Italy
| | - Marco Petitta
- Dept. of Earth Sciences, "Sapienza" University of Roma, Roma 00185, Italy
| | - Henning Prommer
- School of Earth Sciences, University of Western Australia, Crawley 6009 WA, Australia; Ekion Pty Ltd., Swanbourne 6010 WA, Australia
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3
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Latta D, Rosso KM, Scherer MM. Tracking Initial Fe(II)-Driven Ferrihydrite Transformations: A Mössbauer Spectroscopy and Isotope Investigation. ACS EARTH & SPACE CHEMISTRY 2023; 7:1814-1824. [PMID: 37876661 PMCID: PMC10591510 DOI: 10.1021/acsearthspacechem.2c00291] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 05/22/2023] [Accepted: 09/14/2023] [Indexed: 10/26/2023]
Abstract
Transformation of nanocrystalline ferrihydrite to more stable microcrystalline Fe(III) oxides is rapidly accelerated under reducing conditions with aqueous Fe(II) present. While the major steps of Fe(II)-catalyzed ferrihydrite transformation are known, processes in the initial phase that lead to nucleation and the growth of product minerals remain unclear. To track ferrihydrite-Fe(II) interactions during this initial phase, we used Fe isotopes, Mössbauer spectroscopy, and extractions to monitor the structural, magnetic, and isotope composition changes of ferrihydrite within ∼30 min of Fe(II) exposure. We observed rapid isotope mixing between aqueous Fe(II) and ferrihydrite during this initial lag phase. Our findings from Mössbauer spectroscopy indicate that a more magnetically ordered Fe(III) phase initially forms that is distinct from ferrihydrite and bulk crystalline transformation products. The signature of this phase is consistent with the early stage emergence of lepidocrocite-like lamellae observed in previous transmission electron microscopy studies. Its signature is furthermore removed by xylenol extraction of Fe(III), the same approach used to identify a chemically labile form of Fe(III) resulting from Fe(II) contact that is correlated to the ultimate emergence of crystalline product phases detectable by X-ray diffraction. Our work indicates that the mineralogical changes in the initial lag phase of Fh transformation initiated by Fe(II)-Fh electron transfer are critical to understanding ferrihydrite behavior in soils and sediments, particularly with regard to metal uptake and release.
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Affiliation(s)
- Drew Latta
- Department
of Civil and Environmental Engineering/IIHR, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Kevin M. Rosso
- Physical
Sciences Division, Pacific Northwest National
Laboratory, Richland, Washington 99345, United States
| | - Michelle M. Scherer
- Department
of Civil and Environmental Engineering/IIHR, The University of Iowa, Iowa City, Iowa 52242, United States
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Cheng W, Li J, Sun J, Luo T, Marsac R, Boily JF, Hanna K. Nalidixic Acid and Fe(II)/Cu(II) Coadsorption at Goethite and Akaganéite Surfaces. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:15680-15692. [PMID: 37796760 DOI: 10.1021/acs.est.3c05727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/07/2023]
Abstract
Interactions between aqueous Fe(II) and solid Fe(III) oxy(hydr)oxide surfaces play determining roles in the fate of organic contaminants in nature. In this study, the adsorption of nalidixic acid (NA), a representative redox-inactive quinolone antibiotic, on synthetic goethite (α-FeOOH) and akaganéite (β-FeOOH) was examined under varying conditions of pH and cation type and concentration, by means of adsorption experiments, attenuated total reflectance-Fourier transform infrared spectroscopy, surface complexation modeling (SCM), and powder X-ray diffraction. Batch adsorption experiments showed that Fe(II) had marginal effects on NA adsorption onto akaganéite but enhanced NA adsorption on goethite. This enhancement is attributed to the formation of goethite-Fe(II)-NA ternary complexes, without the need for heterogeneous Fe(II)-Fe(III) electron transfer at low Fe(II) loadings (2 Fe/nm2), as confirmed by SCM. However, higher Fe(II) loadings required a goethite-magnetite composite in the SCM to explain Fe(II)-driven recrystallization and its impact on NA binding. The use of a surface ternary complex by SCM was supported further in experiments involving Cu(II), a prevalent environmental metal incapable of transforming Fe(III) oxy(hydr)oxides, which was observed to enhance NA loadings on goethite. However, Cu(II)-NA aqueous complexation and potential Cu(OH)2 precipitates counteracted the formation of ternary surface complexes, leading to decreased NA loadings on akaganéite. These results have direct implications for the fate of organic contaminants, especially those at oxic-anoxic boundaries.
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Affiliation(s)
- Wei Cheng
- College of Resources and Environmental Science, South-Central Minzu University, Wuhan 430074, P. R. China
| | - Jiabin Li
- College of Resources and Environmental Science, South-Central Minzu University, Wuhan 430074, P. R. China
| | - Jie Sun
- College of Resources and Environmental Science, South-Central Minzu University, Wuhan 430074, P. R. China
| | - Tao Luo
- Department of Chemistry, Umeå University, SE-90187 Umeå, Sweden
- Université de Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR-UMR 6226, F-35000 Rennes, France
| | - Rémi Marsac
- Université de Rennes, CNRS, Géosciences Rennes─UMR 6118, F-35000 Rennes, France
| | | | - Khalil Hanna
- Université de Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR-UMR 6226, F-35000 Rennes, France
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5
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Jia QQ, Zhang X, Deng J, Huang LZ. Labile Fe(III) phase mediates the electron transfer from Fe(II,III) (oxyhydr)oxides to carbon tetrachloride. WATER RESEARCH 2023; 245:120636. [PMID: 37748348 DOI: 10.1016/j.watres.2023.120636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 09/09/2023] [Accepted: 09/15/2023] [Indexed: 09/27/2023]
Abstract
Labile Fe(III) phase (includes Fe(III)aq, Fe(III)ads, or Fe(III)s species) is an important intermediate during the interaction between Fe(II) and Fe(III) (oxyhydr)oxides, but how does labile Fe(III) influence the electron transfer from Fe(II) to oxidant environmental pollutant during this Fe(II)-Fe(III) interaction is unclear. In this work, the dynamic change of Fe(II,III) (oxyhydr)oxides at the same time scale is simulated by synthesizing Fe(III)-Fe(II)-I (Fe(III)+NaOH+Fe(II)+NaOH) with different Fe(II)/Fe(III) ratios. CCl4 is used as a convenient probe to test the reduction kinetics of mixed valence Fe(II,III)(oxyhydr)oxides with different Fe(II):Fe(III) ratios. The Mössbauer spectra results reveal the Fe(III)labile in the solid phase is in octahedral coordination. The electron-donating capability of Fe(II) was improved with increasing Fe(III) content, but suppressed when [Fe(III)] ≥ 30 mM. The reductive dechlorination of CT by Fe(III)-Fe(II)-I decreased gradually with the increase of Fe(III) content, because more amount Fe(III)labile in solid phase is accumulated. This shows that the electron transfer from Fe(II) to Fe(III)labile rather than to CT is enhanced with increasing Fe(III) content. FTIR data shows that the hydroxylation of Fe(II) with Fe(OH)3 occurs preferentially in the non-hydrogen bonded hydroxyl group, causing the decrease of its reductive reactivity. The presence of [Fe(III)-O-Fe(II)]+ in Fe(III)-Fe(II)-I can stabilize the dichlorocarbene anion (:CCl2-), favouring the conversion of CT to CH4 (13.1%). The aging experiment shows that Fe(III)labile surface may maintain the reductive reactivity of Fe(II) during aging when [Fe(III)] = 5-20 mM. This study deepens our understanding of the mass transfer pathway of iron oxyhydroxides induced by Fe(II) and its impact on the reductive dechlorination of CT.
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Affiliation(s)
- Qian-Qian Jia
- School of Civil Engineering, Wuhan University, No. 8, East Lake South Road, Wuhan, PR China; State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China
| | - Xuejie Zhang
- School of Civil Engineering, Wuhan University, No. 8, East Lake South Road, Wuhan, PR China; State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China
| | - Jia Deng
- School of Civil Engineering, Wuhan University, No. 8, East Lake South Road, Wuhan, PR China; State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China
| | - Li-Zhi Huang
- School of Civil Engineering, Wuhan University, No. 8, East Lake South Road, Wuhan, PR China; State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China.
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6
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Lei M, Huang Y, Zhou Y, Mensah CO, Wei D, Li B. The role of organic and inorganic substituents of roxarsone determines its binding behavior and mechanisms onto nano-ferrihydrite colloidal particles. J Environ Sci (China) 2023; 129:30-44. [PMID: 36804240 DOI: 10.1016/j.jes.2022.09.035] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 09/23/2022] [Accepted: 09/25/2022] [Indexed: 06/18/2023]
Abstract
The retention and fate of Roxarsone (ROX) onto typical reactive soil minerals were crucial for evaluating its potential environmental risk. However, the behavior and molecular-level reaction mechanism of ROX and its substituents with iron (hydr)oxides remains unclear. Herein, the binding behavior of ROX on ferrihydrite (Fh) was investigated through batch experiments and in-situ ATR-FTIR techniques. Our results demonstrated that Fh is an effective geo-sorbent for the retention of ROX. The pseudo-second-order kinetic and the Langmuir model successfully described the sorption process. The driving force for the binding of ROX on Fh was ascribed to the chemical adsorption, and the rate-limiting step is simultaneously dominated by intraparticle and film diffusion. Isotherms results revealed that the sorption of ROX onto Fh appeared in uniformly distributed monolayer adsorption sites. The two-dimensional correlation spectroscopy and XPS results implied that the nitro, hydroxyl, and arsenate moiety of ROX molecules have participated in binding ROX onto Fh, signifying that the predominated mechanisms were attributed to the hydrogen bonding and surface complexation. Our results can help to better understand the ROX-mineral interactions at the molecular level and lay the foundation for exploring the degradation, transformation, and remediation technologies of ROX and structural analog pollutants in the environment.
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Affiliation(s)
- Ming Lei
- College of Resource & Environment, Hunan Agricultural University, Changsha 410128, China; Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha 410128, China; Key Laboratory of Southern Farmland Pollution Prevention and Control, Ministry of Agriculture, Changsha 410128, China
| | - Yayuan Huang
- College of Resource & Environment, Hunan Agricultural University, Changsha 410128, China; Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha 410128, China; Key Laboratory of Southern Farmland Pollution Prevention and Control, Ministry of Agriculture, Changsha 410128, China
| | - Yimin Zhou
- College of Resource & Environment, Hunan Agricultural University, Changsha 410128, China; Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha 410128, China; Key Laboratory of Southern Farmland Pollution Prevention and Control, Ministry of Agriculture, Changsha 410128, China
| | - Caleb Oppong Mensah
- College of Resource & Environment, Hunan Agricultural University, Changsha 410128, China; Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha 410128, China; Key Laboratory of Southern Farmland Pollution Prevention and Control, Ministry of Agriculture, Changsha 410128, China
| | - Dongning Wei
- College of Resource & Environment, Hunan Agricultural University, Changsha 410128, China; Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha 410128, China; Key Laboratory of Southern Farmland Pollution Prevention and Control, Ministry of Agriculture, Changsha 410128, China
| | - Bingyu Li
- College of Resource & Environment, Hunan Agricultural University, Changsha 410128, China; Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha 410128, China; Key Laboratory of Southern Farmland Pollution Prevention and Control, Ministry of Agriculture, Changsha 410128, China.
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7
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Liu Y, Ding Y, Sheng A, Li X, Chen J, Arai Y, Liu J. Fe(II)-Catalyzed Transformation of Ferrihydrite with Different Degrees of Crystallinity. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:6934-6943. [PMID: 37078588 DOI: 10.1021/acs.est.3c00555] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Natural occurring ferrihydrite (Fh) nanoparticles have varying degrees of crystallinity, but how Fh crystallinity affects its transformation behavior remains elusive. Here, we investigated the Fe(II)-catalyzed transformation of Fh with different degrees of crystallinity (i.e., Fh-2h, Fh-12h, and Fh-85C). X-ray diffraction patterns of Fh-2h, Fh-12h, and Fh-85C exhibited two, five, and six diffraction peaks, respectively, indicating the order of crystallinity: Fh-2h < Fh-12h < Fh-85C. Fh with the lower crystallinity has a higher redox potential, corresponding to the faster Fe(II)-Fh interfacial electron transfer and Fe(III)labile production. With the increase of initial Fe(II) concentration ([Fe(II)aq]int.) from 0.2 to 5.0 mM, the transformation pathways of Fh-2h and Fh-12h change from Fh → lepidocrocite (Lp) → goethite (Gt) to Fh → Gt, but that of Fh-85C switches from Fh → Gt to Fh → magnetite (Mt). The changes are rationalized using a computational model that quantitatively describes the relationship between the free energies of formation for starting Fh and nucleation barriers of competing product phases. Gt particles from the Fh-2h transformation exhibit a broader width distribution than those from Fh-12h and Fh-85C. Uncommon hexagonal Mt nanoplates are formed from the Fh-85C transformation at [Fe(II)aq]int.= 5.0 mM. The findings are crucial to comprehensively understand the environmental behavior of Fh and other associated elements.
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Affiliation(s)
- Yuyan Liu
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yuefei Ding
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Anxu Sheng
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Xiaoxu Li
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Jiawei Chen
- School of Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China
| | - Yuji Arai
- Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, 1102 South Goodwin Avenue, Urbana, Illinois 61801, United States
| | - Juan Liu
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- International Joint Laboratory for Regional Pollution Control, Ministry of Education, College of Environmental Sciences and Engineering, Beijing 100871, China
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8
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Zhang P, Meng X, Liu A, Ma M, Shao Y, Sun H. Biochar-derived dissolved black carbon accelerates ferrihydrite microbial transformation and subsequent imidacloprid degradation. JOURNAL OF HAZARDOUS MATERIALS 2023; 446:130685. [PMID: 36584647 DOI: 10.1016/j.jhazmat.2022.130685] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 12/25/2022] [Accepted: 12/26/2022] [Indexed: 06/17/2023]
Abstract
The effects of an electron shuttle (dissolved black carbon (DBC) derived from biochar) on the microbial reduction of ferrihydrite and subsequent imidacloprid (IMI) degradation were studied. The results showed that DBC addition enhanced the microbial reduction of Fe(III) in ferrihydrite and increased the quantity of Fe(II) released into the liquid phase. The electron transfer capacity of DBC was significantly influenced by the content of redox-active oxygen-containing functional groups (e.g., quinone, hydroquinone, and polyphenol groups), which was dependent on the pyrolysis temperature. The electrochemical characteristics of DBC resulted in enhanced electron transfer, which promoted Fe(III) reduction and mediated the microbial transformation of ferrihydrite. The microbial transformation of ferrihydrite resulted in the formation of secondary minerals such as siderite and vivianite. The IMI degradation efficiency was related to the Fe(III) reduction rate and the pyrolysis temperature used in DBC production, and the degradation pathways were nitrate reduction and imino hydrolysis induced by the Fe(II) generated from the reduction of Fe(III) in ferrihydrite. The results obtained in this study provide new data for understanding the multifunctional roles of biochar-derived DBC in the redox and transformation processes of iron minerals induced by iron-reducing bacteria, the related biogeochemical cycles of iron and the fate of pollutants.
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Affiliation(s)
- Peng Zhang
- Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, Tianjin 300350, China; MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
| | - Xingying Meng
- Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, Tianjin 300350, China; MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Aiju Liu
- School of Resources and Environmental Engineering, Shandong University of Technology, Zibo 255049, China
| | - Mingming Ma
- Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, Tianjin 300350, China; MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Yifei Shao
- School of Resources and Environmental Engineering, Shandong University of Technology, Zibo 255049, China
| | - Hongwen Sun
- Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, Tianjin 300350, China; MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
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9
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Liu X, Cai X, Wang P, Yin N, Fan C, Chang X, Huang X, Du X, Wang S, Cui Y. Effect of manganese oxides on arsenic speciation and mobilization in different arsenic-adsorbed iron-minerals under microbially-reducing conditions. JOURNAL OF HAZARDOUS MATERIALS 2023; 445:130602. [PMID: 37055999 DOI: 10.1016/j.jhazmat.2022.130602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 12/09/2022] [Accepted: 12/11/2022] [Indexed: 06/19/2023]
Abstract
The oxidation and immobilization of arsenic (As) by manganese oxides have been shown to reduce As toxicity and bioavailability under abiotic conditions. In this study, we investigate the impact of manganese oxide (δ-MnO2) on the fate of different Fe-minerals-adsorbed As in the presence of As(V)-reducing bacteria Bacillus sp. JQ. Results showed that in the absence of δ-MnO2, As release in goethite was much higher than in ferrihydrite and hematite during microbial reduction. Adding 3.1 mM Mn reduced As release by 0.3%, 46.3%, and 6.7% in the ferrihydrite, goethite, and hematite groups, respectively. However, aqueous As was dominated by As(III) in the end, because the oxidation effect of δ-MnO2 was limited and short-lived. Additionally, the fraction of solid-phase As(V) increased by 9.8% in ferrihydrite, 39.4% in goethite, and 7.4% in hematite in the high-Mn treatments, indicating that δ-MnO2 had the most significant oxidation and immobilization effect on goethite-adsorbed As. This was achieved because goethite particles were evenly distributed on δ-MnO2 surface, which supported As(III) oxidation by δ-MnO2; while ferrihydrite strongly aggregated, which hindered the oxidation of As(III). Our study shows that As-oxidation and immobilization by manganese oxides cannot easily be assessed without considering the mineral composition and microbial conditions of soils.
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Affiliation(s)
- Xiaotong Liu
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, PR China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
| | - Xiaolin Cai
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, PR China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China.
| | - Pengfei Wang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, PR China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
| | - Naiyi Yin
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, PR China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
| | - Chuanfang Fan
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, PR China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
| | - Xuhui Chang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, PR China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
| | - Xuhan Huang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, PR China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
| | - Xin Du
- CHINALCO Environmental protection and Energy Conservation Group Co. Ltd., Beijing 102209, PR China
| | - Shuping Wang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, PR China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China.
| | - Yanshan Cui
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, PR China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
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10
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Grigg ARC, ThomasArrigo LK, Schulz K, Rothwell KA, Kaegi R, Kretzschmar R. Ferrihydrite transformations in flooded paddy soils: rates, pathways, and product spatial distributions. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2022; 24:1867-1882. [PMID: 36131682 PMCID: PMC9580987 DOI: 10.1039/d2em00290f] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 09/15/2022] [Indexed: 06/15/2023]
Abstract
Complex interactions between redox-driven element cycles in soils influence iron mineral transformation processes. The rates and pathways of iron mineral transformation processes have been studied intensely in model systems such as mixed suspensions, but transformation in complex heterogeneous porous media is not well understood. Here, mesh bags containing 0.5 g of ferrihydrite were incubated in five water-saturated paddy soils with contrasting microbial iron-reduction potential for up to twelve weeks. Using X-ray diffraction analysis, we show near-complete transformation of the ferrihydrite to lepidocrocite and goethite within six weeks in the soil with the highest iron(II) release, and slower transformation with higher ratios of goethite to lepidocrocite in soils with lower iron(II) release. In the least reduced soil, no mineral transformations were observed. In soils where ferrihydrite transformation occurred, the transformation rate was one to three orders of magnitude slower than transformation in comparable mixed-suspension studies. To interpret the spatial distribution of ferrihydrite and its transformation products, we developed a novel application of confocal micro-Raman spectroscopy in which we identified and mapped minerals on selected cross sections of mesh bag contents. After two weeks of flooded incubation, ferrihydrite was still abundant in the core of some mesh bags, and as a rim at the mineral-soil interface. The reacted outer core contained unevenly mixed ferrihydrite, goethite and lepidocrocite on the micrometre scale. The slower rate of transformation and uneven distribution of product minerals highlight the influence of biogeochemically complex matrices and diffusion processes on the transformation of minerals, and the importance of studying iron mineral transformation in environmental media.
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Affiliation(s)
- Andrew R C Grigg
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 16, CHN, CH-8092 Zurich, Switzerland.
| | - 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.
| | - Katrin Schulz
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 16, CHN, CH-8092 Zurich, Switzerland.
| | - Katherine A Rothwell
- 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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11
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Patzner M, Kainz N, Lundin E, Barczok M, Smith C, Herndon E, Kinsman-Costello L, Fischer S, Straub D, Kleindienst S, Kappler A, Bryce C. Seasonal Fluctuations in Iron Cycling in Thawing Permafrost Peatlands. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:4620-4631. [PMID: 35290040 PMCID: PMC9097474 DOI: 10.1021/acs.est.1c06937] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 03/01/2022] [Accepted: 03/02/2022] [Indexed: 06/14/2023]
Abstract
In permafrost peatlands, up to 20% of total organic carbon (OC) is bound to reactive iron (Fe) minerals in the active layer overlying intact permafrost, potentially protecting OC from microbial degradation and transformation into greenhouse gases (GHG) such as CO2 and CH4. During the summer, shifts in runoff and soil moisture influence redox conditions and therefore the balance of Fe oxidation and reduction. Whether reactive iron minerals could act as a stable sink for carbon or whether they are continuously dissolved and reprecipitated during redox shifts remains unknown. We deployed bags of synthetic ferrihydrite (FH)-coated sand in the active layer along a permafrost thaw gradient in Stordalen mire (Abisko, Sweden) over the summer (June to September) to capture changes in redox conditions and quantify the formation and dissolution of reactive Fe(III) (oxyhydr)oxides. We found that the bags accumulated Fe(III) under constant oxic conditions in areas overlying intact permafrost over the full summer season. In contrast, in fully thawed areas, conditions were continuously anoxic, and by late summer, 50.4 ± 12.8% of the original Fe(III) (oxyhydr)oxides were lost via dissolution. Periodic redox shifts (from 0 to +300 mV) were observed over the summer season in the partially thawed areas. This resulted in the dissolution and loss of 47.2 ± 20.3% of initial Fe(III) (oxyhydr)oxides when conditions are wetter and more reduced, and new formation of Fe(III) minerals (33.7 ± 8.6% gain in comparison to initial Fe) in the late summer under more dry and oxic conditions, which also led to the sequestration of Fe-bound organic carbon. Our data suggest that there is seasonal turnover of iron minerals in partially thawed permafrost peatlands, but that a fraction of the Fe pool remains stable even under continuously anoxic conditions.
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Affiliation(s)
- Monique
S. Patzner
- Geomicrobiology,
Center for Applied Geosciences, University
of Tuebingen, Schnarrenbergstrasse 94-96, 72076 Tuebingen, Germany
| | - Nora Kainz
- Geomicrobiology,
Center for Applied Geosciences, University
of Tuebingen, Schnarrenbergstrasse 94-96, 72076 Tuebingen, Germany
| | - Erik Lundin
- Abisko
Scientific Research Station, Swedish Polar
Research Secretariat, Vetenskapens väg 38, SE-891
07 Abisko, Sweden
| | - Maximilian Barczok
- Department
of Geology, Kent State University, Kent, Ohio 44242, United States
| | - Chelsea Smith
- Department
of Biological Sciences, Kent State University, Kent, Ohio 44242, United States
| | - Elizabeth Herndon
- Environmental
Sciences Division, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37830, United States
| | | | - Stefan Fischer
- Tuebingen
Structural Microscopy Core Facility, Center for Applied Geosciences, University Tuebingen, Schnarrenbergstrasse 94-96, 72076 Tuebingen, Germany
| | - Daniel Straub
- Microbial
Ecology, Center for Applied Geosciences, University Tuebingen, Schnarrenbergstrasse 94-96, 72076 Tuebingen, Germany
- Quantitative
Biology Center (QBiC), University Tuebingen, Auf der Morgenstelle 10, 72076 Tuebingen, Germany
| | - Sara Kleindienst
- Microbial
Ecology, Center for Applied Geosciences, University Tuebingen, Schnarrenbergstrasse 94-96, 72076 Tuebingen, Germany
| | - Andreas Kappler
- Geomicrobiology,
Center for Applied Geosciences, University
of Tuebingen, Schnarrenbergstrasse 94-96, 72076 Tuebingen, Germany
- Cluster
of Excellence: EXC 2124: Controlling Microbes to Fight Infection, 72074 Tübingen, Germany
| | - Casey Bryce
- School
of Earth Sciences, University of Bristol, Bristol BS8 1RJ, U.K.
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12
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Liu J, Sheng A, Li X, Arai Y, Ding Y, Nie M, Yan M, Rosso KM. Understanding the Importance of Labile Fe(III) during Fe(II)-Catalyzed Transformation of Metastable Iron Oxyhydroxides. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:3801-3811. [PMID: 35188748 DOI: 10.1021/acs.est.1c08044] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Transformation of metastable Fe(III) oxyhydroxides is a prominent process in natural environments and can be significantly accelerated by the coexisting aqueous Fe(II) (Fe(II)aq). Recent evidence points to the solution mass transfer of labile Fe(III) (Fe(III)labile) as the primary intermediate species of general importance. However, a mechanistic aspect that remains unclear is the dependence of phase outcomes on the identity of the metastable Fe(III) oxyhydroxide precursor. Here, we compared the coupled evolution of Fe(II) species, solid phases, and Fe(III)labile throughout the Fe(II)-catalyzed transformation of lepidocrocite (Lp) versus ferrihydrite (Fh) at equal Fe(III) mass loadings with 0.2-1.0 mM Fe(II)aq at pH = 7.0. Similar to Fh, the conversion of Lp to product phases occurs by a dissolution-reprecipitation mechanism mediated by Fe(III)labile that seeds the nucleation of products. Though for Fh we observed a transformation to goethite (Gt), accompanied by the transient emergence and decline of Lp, for initial Lp we observed magnetite (Mt) as the main product. A linear correlation between the formation rate of Mt and the effective supersaturation in terms of Fe(III)labile concentration shows that Fe(II)-induced transformation of Lp into Mt is governed by the classical nucleation theory. When Lp is replaced by equimolar Gt, Mt formation is suppressed by opening a lower barrier pathway to Gt by heterogeneous nucleation and growth on the added Gt seeds. The collective findings add to the mechanistic understanding of factors governing phase selections that impact iron bioavailability, system redox potential, and the fate and transport of coupled elements.
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Affiliation(s)
- Juan Liu
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Anxu Sheng
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Xiaoxu Li
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yuji Arai
- Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, 1102 South Goodwin Avenue, Urbana, Illinois 61801, United States
| | - Yuefei Ding
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Mingjun Nie
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Mingquan Yan
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Kevin M Rosso
- Pacific Northwest National Laboratory, Richland, Washington 99354, United States
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13
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Barron A, Sun J, Passaretti S, Sbarbati C, Barbieri M, Colombani N, Jamieson J, Bostick BC, Zheng Y, Mastrocicco M, Petitta M, Prommer H. In situ arsenic immobilisation for coastal aquifers using stimulated iron cycling: Lab-based viability assessment. APPLIED GEOCHEMISTRY : JOURNAL OF THE INTERNATIONAL ASSOCIATION OF GEOCHEMISTRY AND COSMOCHEMISTRY 2022; 136:105155. [PMID: 34955596 PMCID: PMC8699153 DOI: 10.1016/j.apgeochem.2021.105155] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Arsenic (As) is one of the most harmful and widespread groundwater contaminants globally. Besides the occurrence of geogenic As pollution, there is also a large number of sites that have been polluted by anthropogenic activities, with many of those requiring active remediation to reduce their environmental impact. Cost-effective remedial strategies are however still sorely needed. At the laboratory-scale in situ formation of magnetite through the joint addition of nitrate and Fe(II) has shown to be a promising new technique. However, its applicability under a wider range of environmental conditions still needs to be assessed. Here we use sediment and groundwater from a severely polluted coastal aquifer and explore the efficiency of nitrate-Fe(II) treatments in mitigating dissolved As concentrations. In selected experiments >99% of dissolved As was removed, compared to unamended controls, and maintained upon addition of lactate, a labile organic carbon source. Pre- and post experimental characterisation of iron (Fe) mineral phases suggested a >90% loss of amorphous Fe oxides in favour of increased crystalline, recalcitrant oxide and sulfide phases. Magnetite formation did not occur via the nitrate-dependent oxidation of the amended Fe(II) as originally expected. Instead, magnetite is thought to have formed by the Fe(II)-catalysed transformation of pre-existing amorphous and crystalline Fe oxides. The extent of amorphous and crystalline Fe oxide transformation was then limited by the exhaustion of dissolved Fe(II). Elevated phosphate concentrations lowered the treatment efficacy indicating joint removal of phosphate is necessary for maximum impact. The remedial efficiency was not impacted by varying salinities, thus rendering the tested approach a viable remediation method for coastal aquifers.
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Affiliation(s)
- Alyssa Barron
- School of Earth Sciences, University of Western Australia, Crawley, WA, Australia
- CSIRO Land and Water, Wembley Australia
| | - Jing Sun
- School of Earth Sciences, University of Western Australia, Crawley, WA, Australia
- CSIRO Land and Water, Wembley Australia
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China
| | | | - Chiara Sbarbati
- Dept. of Earth Sciences, “Sapienza” University of Roma, Roma, Italy
| | | | | | - James Jamieson
- School of Earth Sciences, University of Western Australia, Crawley, WA, Australia
- CSIRO Land and Water, Wembley Australia
| | | | - Yan Zheng
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen (China)
| | | | - Marco Petitta
- Dept. of Earth Sciences, “Sapienza” University of Roma, Roma, Italy
| | - Henning Prommer
- School of Earth Sciences, University of Western Australia, Crawley, WA, Australia
- CSIRO Land and Water, Wembley Australia
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14
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Yin X, Zhang G, Su R, Zeng X, Yan Z, Zhang D, Ma X, Lei L, Lin J, Wang S, Jia Y. Oxidation and incorporation of adsorbed antimonite during iron(II)-catalyzed recrystallization of ferrihydrite. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 778:146424. [PMID: 34030383 DOI: 10.1016/j.scitotenv.2021.146424] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 03/08/2021] [Accepted: 03/08/2021] [Indexed: 06/12/2023]
Abstract
The toxicity and mobility of antimony (Sb) are strongly influenced by the redox transformation of widely spread 2-line ferrihydrite (Fh) in natural soils and sediments. This study investigated the transformation and redistribution of adsorbed antimonite (Sb(III)) during Fe(II)-catalyzed recrystallization of Fh under anaerobic conditions. X-ray diffraction (XRD), transmission electron microscopy (TEM), and synchrotron based X-ray absorption spectroscopy (XAS) were utilized to characterize the mineralogy and morphology of generated minerals as well as the speciation of Sb and Fe. Chemical analysis and Sb LIII-edge XANES spectra demonstrated that a great part of Sb(III) (80%-90%) was oxidized to Sb(V) by reactive oxygen species (ROS) during the Fe(II)-catalyzed transformation of Fh. Chemical extraction results showed that the mobility of Sb was significantly reduced with 50%-70% of initially adsorbed Sb(III) transformed to phosphate-unextractable phase. Antimony K-edge EXAFS analysis showed the SbO6 octahedra were incorporated into secondary minerals by substituting the Fe atoms. Our findings shed new light on the understanding of the geochemical behavior of Sb(III) under anoxic conditions.
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Affiliation(s)
- Xiuling Yin
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Guoqing Zhang
- Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, School of Environment, Henan Normal University, Xinxiang 453007, China
| | - Rui Su
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Xiangfeng Zeng
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China
| | - Zelong Yan
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Danni Zhang
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China
| | - Xu Ma
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Lei Lei
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China
| | - Jinru Lin
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China
| | - Shaofeng Wang
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
| | - Yongfeng Jia
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China
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15
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Yang Y, Zhao Z, Zhang Y. Anaerobic Ammonium Removal Pathway Driven by the Fe(II)/Fe(III) Cycle through Intermittent Aeration. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:7615-7623. [PMID: 34014661 DOI: 10.1021/acs.est.0c08624] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Feammox, that is, Fe(III) reduction coupled to anaerobic ammonium oxidation, has been reported to play an important role in the nitrogen cycle in natural environments. However, the application of Feammox in wastewater treatment is limited because continuous Fe(III) supplementation is required for achieving continuous nitrogen removal, which is not feasible in practice. In this study, air was aerated intermittently into the Feammox system containing iron and high-content ammonium for oxidizing Fe(II) generated from Feammox to Fe(III), then, the produced Fe(III) participated in the next round of Feammox, leading to continuous nitrogen removal through the Fe(II)/Fe(III) cycle. The results showed that after each 10 min of aeration (150 mL/min), every 6-7 days, dissolved oxygen (DO) increased from 0 to about 0.4 mg/L, accompanied by a decrease in Fe(II) and an increase in Fe(III). One day after the aeration, DO was undetectable, and then, Fe(II) content increased and Fe(III) content decreased. On day 90, NH4+-N content in the aerated reactor was only 10.2 mg/L, while it remained at around 288.3 mg/L in the aeration-free group. X-ray diffraction showed that the generated Fe(III) through air aeration was Fe(OH)3. Microbial analysis showed that anammox and nitrification/denitrification could be excluded in the system. This NH4+ removal process, driven by the Fe(II)/Fe(III) cycle with O2 as the terminal electron acceptor, might be used as an in situ remediation method for treating high-content NH4+.
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Affiliation(s)
- Yafei Yang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
- School of Ecology and Environment, Zhengzhou University, Zhengzhou 450001, China
| | - Zhiqiang Zhao
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Yaobin Zhang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
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16
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Liu L, Liu G, Zhou J, Jin R. Interaction between hexavalent chromium and biologically formed iron mineral-biochar composites: Kinetics, products and mechanisms. JOURNAL OF HAZARDOUS MATERIALS 2021; 405:124246. [PMID: 33097346 DOI: 10.1016/j.jhazmat.2020.124246] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/08/2020] [Accepted: 10/08/2020] [Indexed: 06/11/2023]
Abstract
Biogenic Fe(II) is a dominant natural reductant to convert carcinogenic Cr(VI) to less toxic Cr(III). Field-applied biochar could promote microbial production of Fe(II) and form iron-biochar composites. Although there have been mounting research on the interactions of biochar or Fe(II) with Cr(VI), their coupling effects on Cr(VI) immobilization have been largely neglected. Here, iron mineral-biochar composite (IMBC) was prepared via biochar-mediated dissimilatory reduction of ferrihydrite or goethite by Shewanella oneidensis MR-1, and its reaction with Cr(VI) was investigated. IMBC was able to effectively remove aqueous Cr(VI) via reductive transformation by adsorbed Fe(II). The removal process nicely followed pseudo-second-order kinetics and Langmuir isotherm model. The removal ability of IMBC decreased with increasing pH (5.5-8.0) but was independent of ionic strength changes (0-100 mM). After reaction, the Fe-Cr coprecipitates formed on IMBC exhibited slightly higher Fe/Cr ratios (0.93-0.96) than those on corresponding iron mineral controls (0.88-0.94). For IMBC, while the presence of biochar decreased the reactivity of adsorbed Fe(II), their removal capacities were ~30% higher than those of iron minerals alone, due to the enhanced yields of adsorbed Fe(II). These findings improved our knowledge of interactions among biochar, iron mineral and iron-reducing bacteria and their contribution to chromium immobilization.
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Affiliation(s)
- Lecheng Liu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Guangfei Liu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China; Key Laboratory of Eco-restoration of Regional Contaminated Environment, Shenyang University, Shenyang 110000, China.
| | - Jiti Zhou
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Ruofei Jin
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
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17
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Quinone-mediated dissimilatory iron reduction of hematite: Interfacial reactions on exposed {0 0 1} and {1 0 0} facets. J Colloid Interface Sci 2021; 583:544-552. [DOI: 10.1016/j.jcis.2020.09.074] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 09/17/2020] [Accepted: 09/20/2020] [Indexed: 11/23/2022]
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18
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Giannetta B, Balint R, Said-Pullicino D, Plaza C, Martin M, Zaccone C. Fe(II)-catalyzed transformation of Fe (oxyhydr)oxides across organic matter fractions in organically amended soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 748:141125. [PMID: 32798857 DOI: 10.1016/j.scitotenv.2020.141125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 07/17/2020] [Accepted: 07/18/2020] [Indexed: 06/11/2023]
Abstract
The Fe(II)-catalyzed transformation of ferrihydrite into highly crystalline forms may represent an important pathway for soil organic matter (SOM) destabilization under moderately reducing conditions. However, the link between redox-driven changes in soil Fe mineral composition and crystallinity and SOM chemical properties in the field remains elusive. We evaluated abiotic Fe(II)-catalyzed mineralogical transformation of Fe (oxyhydr)oxides in bulk soils and two particle-size SOM fractions, namely the fine silt plus clay (<20 μm, FSi + Cl) and fine sand (50-200 μm, FSa) fractions of an agricultural soil unamended or amended with biochar, compost, or the combination of both. After spiking with Fe(II) and incubating for 7 days under anoxic and sterile conditions at neutral pH, the FSa fractions (Fe(II):Fe (III) molar ratios ≈ 3.3) showed more significant ferrihydrite transformations with respect to FSi + Cl fractions (Fe(II):Fe (III) molar ratios ≈ 0.7), with the consequent production of well-ordered Fe oxides in most soils, particularly those unamended or amended with biochar alone. Nonetheless, poorly crystalline ferrihydrite still constituted about 45% of the FSi + Cl fractions of amended soils after reaction with Fe(II), which confirms that the higher SOM and clay mineral content in this fraction may possibly inhibit atom exchange between aqueous Fe(II) and the solid phase. Building on our knowledge of abiotic Fe(II)-catalyzed mineralogical changes, the suppression of ferrihydrite transformation in FSi + Cl fractions in amended soils could ultimately lead to a slower turnover of ferrihydrite, possibly preserving the carbon sequestration potential associated with this mineral. Conversely, in both bulk soils and FSa fractions, the extent to which mineral transformation occur seemed to be contingent on the quality of the amendment used.
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Affiliation(s)
- Beatrice Giannetta
- Department of Agricultural, Forest and Food Sciences, University of Torino, Largo Paolo Braccini 2, 10095 Grugliasco, Italy.
| | - Ramona Balint
- Department of Agricultural, Forest and Food Sciences, University of Torino, Largo Paolo Braccini 2, 10095 Grugliasco, Italy; Institute of Geosciences and Earth Resources, National Research Council of Italy (CNR), Via Valperga Caluso 35, 10125 Turin, Italy
| | - Daniel Said-Pullicino
- Department of Agricultural, Forest and Food Sciences, University of Torino, Largo Paolo Braccini 2, 10095 Grugliasco, Italy
| | - César Plaza
- Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones Científicas, Serrano 115 bis, 28006 Madrid, Spain
| | - Maria Martin
- Department of Agricultural, Forest and Food Sciences, University of Torino, Largo Paolo Braccini 2, 10095 Grugliasco, Italy
| | - Claudio Zaccone
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, Verona 37134, Italy
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19
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Benaiges-Fernandez R, Offeddu FG, Margalef-Marti R, Palau J, Urmeneta J, Carrey R, Otero N, Cama J. Geochemical and isotopic study of abiotic nitrite reduction coupled to biologically produced Fe(II) oxidation in marine environments. CHEMOSPHERE 2020; 260:127554. [PMID: 32688313 DOI: 10.1016/j.chemosphere.2020.127554] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 06/25/2020] [Accepted: 06/27/2020] [Indexed: 06/11/2023]
Abstract
Estuarine sediments are often characterized by abundant iron oxides, organic matter, and anthropogenic nitrogen compounds (e.g., nitrate and nitrite). Anoxic dissimilatory iron reducing bacteria (e.g., Shewanella loihica) are ubiquitous in these environments where they can catalyze the reduction of Fe(III) (oxyhydr)oxides, thereby releasing aqueous Fe(II). The biologically produced Fe(II) can later reduce nitrite to form nitrous oxide. The effect on nitrite reduction by both biologically produced and artificially amended Fe(II) was examined experimentally. Ferrihydrite was reduced by Shewanella loihica in a batch reaction with an anoxic synthetic sea water medium. Some of the Fe(II) released by S. loihica adsorbed onto ferrihydrite, which was involved in the transformation of ferrihydrite to magnetite. In a second set of experiments with identical medium, no microorganism was present, instead, Fe(II) was amended. The amount of solid-bound Fe(II) in the experiments with bioproduced Fe(II) increased the rate of abiotic NO2- reduction with respect to that with synthetic Fe(II), yielding half-lives of 0.07 and 0.47 d, respectively. The δ18O and δ15N of NO2- was measured through time for both the abiotic and innoculated experiments. The ratio of ε18O/ε15N was 0.6 for the abiotic experiments and 3.1 when NO2- was reduced by S. loihica, thus indicating two different mechanisms for the NO2- reduction. Notably, there is a wide range of the ε18O/ε15N values in the literature for abiotic and biotic NO2- reduction, as such, the use of this ratio to distinguish between reduction mechanisms in natural systems should be taken with caution. Therefore, we suggest an additional constraint to identify the mechanisms (i.e. abiotic/biotic) controlling NO2- reduction in natural settings through the correlation of δ15N-NO2- and the aqueous Fe(II) concentration.
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Affiliation(s)
- R Benaiges-Fernandez
- Institute of Environmental Assessment and Water Research (IDAEA, CSIC), 08034, Barcelona, Catalonia, Spain; Departament de Genètica, Microbiologia I Estadística, Universitat de Barcelona, 08028, Barcelona, Catalonia, Spain.
| | - F G Offeddu
- Institute of Environmental Assessment and Water Research (IDAEA, CSIC), 08034, Barcelona, Catalonia, Spain
| | - R Margalef-Marti
- Grup MAiMA, SGR Mineralogia Aplicada, Geoquímica I Geomicrobiologia, Departament de Mineralogia, Petrologia I Geologia Aplicada, Facultat de Ciències de La Terra, Universitat de Barcelona (UB), 08028, Barcelona, Catalonia, Spain; Institut de Recerca de L'Aigua (IdRA), Universitat de Barcelona (UB), 08001, Barcelona, Catalonia, Spain
| | - J Palau
- Institute of Environmental Assessment and Water Research (IDAEA, CSIC), 08034, Barcelona, Catalonia, Spain; Grup MAiMA, SGR Mineralogia Aplicada, Geoquímica I Geomicrobiologia, Departament de Mineralogia, Petrologia I Geologia Aplicada, Facultat de Ciències de La Terra, Universitat de Barcelona (UB), 08028, Barcelona, Catalonia, Spain; Institut de Recerca de L'Aigua (IdRA), Universitat de Barcelona (UB), 08001, Barcelona, Catalonia, Spain
| | - J Urmeneta
- Departament de Genètica, Microbiologia I Estadística, Universitat de Barcelona, 08028, Barcelona, Catalonia, Spain; Institut de Recerca de La Biodiversitat (IRBio), Universitat de Barcelona, 08028, Barcelona, Catalonia, Spain
| | - R Carrey
- Grup MAiMA, SGR Mineralogia Aplicada, Geoquímica I Geomicrobiologia, Departament de Mineralogia, Petrologia I Geologia Aplicada, Facultat de Ciències de La Terra, Universitat de Barcelona (UB), 08028, Barcelona, Catalonia, Spain; Institut de Recerca de L'Aigua (IdRA), Universitat de Barcelona (UB), 08001, Barcelona, Catalonia, Spain
| | - N Otero
- Grup MAiMA, SGR Mineralogia Aplicada, Geoquímica I Geomicrobiologia, Departament de Mineralogia, Petrologia I Geologia Aplicada, Facultat de Ciències de La Terra, Universitat de Barcelona (UB), 08028, Barcelona, Catalonia, Spain; Institut de Recerca de L'Aigua (IdRA), Universitat de Barcelona (UB), 08001, Barcelona, Catalonia, Spain; Serra Húnter Fellowship. Generalitat de Catalunya, Catalonia, Spain
| | - J Cama
- Institute of Environmental Assessment and Water Research (IDAEA, CSIC), 08034, Barcelona, Catalonia, Spain
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20
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Gomez MA, Jiang R, Song M, Li D, Lea AS, Ma X, Wang H, Yin X, Wang S, Jia Y. Further insights into the Fe(ii) reduction of 2-line ferrihydrite: a semi in situ and in situ TEM study. NANOSCALE ADVANCES 2020; 2:4938-4950. [PMID: 36132886 PMCID: PMC9417501 DOI: 10.1039/d0na00643b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 09/22/2020] [Indexed: 05/26/2023]
Abstract
The biotic or abiotic reduction of nano-crystalline 2-line ferrihydrite (2-line FH) into more thermodynamically stable phases such as lepidocrocite-LP, goethite-GT, magnetite-MG, and hematite-HT plays an important role in the geochemical cycling of elements and nutrients in aqueous systems. In our study, we employed the use of in situ liquid cell (LC) and semi in situ analysis in an environmental TEM to gain further insights at the micro/nano-scale into the reaction mechanisms by which Fe(ii)(aq) catalyzes 2-line FH. We visually observed for the first time the following intermediate steps: (1) formation of round and wire-shaped precursor nano-particles arising only from Fe(ii)(aq), (2) two distinct dissolution mechanisms for 2 line-FH (i.e. reduction of size and density as well as breakage through smaller nano-particles), (3) lack of complete dissolution of 2-line FH (i.e. "induction-period"), (4) an amorphous phase growth ("reactive-FH/labile Fe(iii) phase") on 2 line-FH, (5) deposition of amorphous nano-particles on the surface of 2 line-FH and (6) assemblage of elongated crystalline lamellae to form tabular LP crystals. Furthermore, we observed phenomena consistent with the movement of adsorbate ions from solution onto the surface of a Fe(iii)-oxy/hydroxide crystal. Thus our work here reveals that the catalytic transformation of 2-line FH by Fe(ii)(aq) at the micro/nano scale doesn't simply occur via dissolution-reprecipitation or surface nucleation-solid state conversion mechanisms. Rather, as we demonstrate here, it is an intricate chemical process that goes through a series of intermediate steps not visible through conventional lab or synchrotron bulk techniques. However, such intermediate steps may affect the environmental fate, bioavailability, and transport of elements of such nano-particles in aqueous environments.
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Affiliation(s)
- Mario Alberto Gomez
- Liaoning Engineering Research Center for Treatment and Recycling of Industrially Discharged Heavy Metals, Shenyang University of Chemical Technology Shenyang Liaoning 110142 China +86 15093716277 +86 15140014967
- Department of Geological Sciences, University of Saskatchewan Saskatoon Saskatchewan S7N 5E2 Canada
| | - Ruonan Jiang
- Liaoning Engineering Research Center for Treatment and Recycling of Industrially Discharged Heavy Metals, Shenyang University of Chemical Technology Shenyang Liaoning 110142 China +86 15093716277 +86 15140014967
| | - Miao Song
- Physical and Computational Science Directorate, Pacific Northwest National Laboratory Richland Washington 99352 USA +1 5093716242 +1 5093716277
| | - Dongsheng Li
- Physical and Computational Science Directorate, Pacific Northwest National Laboratory Richland Washington 99352 USA +1 5093716242 +1 5093716277
| | - Alan Scott Lea
- Environmental and Biological Sciences Directorate, Pacific Northwest National Laboratory Richland Washington 99352 USA
| | - Xu Ma
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences Shenyang 110016 Liaoning China
| | - Haibo Wang
- Liaoning Engineering Research Center for Treatment and Recycling of Industrially Discharged Heavy Metals, Shenyang University of Chemical Technology Shenyang Liaoning 110142 China +86 15093716277 +86 15140014967
| | - Xiuling Yin
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences Shenyang 110016 Liaoning China
| | - Shaofeng Wang
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences Shenyang 110016 Liaoning China
| | - Yongfeng Jia
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences Shenyang 110016 Liaoning China
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21
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Beltrán-Suito R, Forstner V, Hausmann JN, Mebs S, Schmidt J, Zaharieva I, Laun K, Zebger I, Dau H, Menezes PW, Driess M. A soft molecular 2Fe-2As precursor approach to the synthesis of nanostructured FeAs for efficient electrocatalytic water oxidation. Chem Sci 2020; 11:11834-11842. [PMID: 34123210 PMCID: PMC8162750 DOI: 10.1039/d0sc04384b] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Accepted: 10/07/2020] [Indexed: 12/03/2022] Open
Abstract
An unprecedented molecular 2Fe-2As precursor complex was synthesized and transformed under soft reaction conditions to produce an active and long-term stable nanocrystalline FeAs material for electrocatalytic water oxidation in alkaline media. The 2Fe2As-centred β-diketiminato complex, having an unusual planar Fe2As2 core structure, results from the salt-metathesis reaction of the corresponding β-diketiminato FeIICl complex and the AsCO- (arsaethynolate) anion as the monoanionic As- source. The as-prepared FeAs phase produced from the precursor has been electrophoretically deposited on conductive electrode substrates and shown to act as a electro(pre)catalyst for the oxygen evolution reaction (OER). The deposited FeAs undergoes corrosion under the severe anodic alkaline conditions which causes extensive dissolution of As into the electrolyte forming finally an active two-line ferrihydrite phase (Fe2O3(H2O) x ). Importantly, the dissolved As in the electrolyte can be fully recaptured (electro-deposited) at the counter electrode making the complete process eco-conscious. The results represent a new and facile entry to unexplored nanostructured transition-metal arsenides and their utilization for high-performance OER electrocatalysis, which are also known to be magnificent high-temperature superconductors.
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Affiliation(s)
- Rodrigo Beltrán-Suito
- Department of Chemistry: Metalorganics and Inorganic Materials, Technische Universität Berlin Straße des 17 Juni 135, Sekr. C2 10623 Berlin Germany
| | - Viktoria Forstner
- Department of Chemistry: Metalorganics and Inorganic Materials, Technische Universität Berlin Straße des 17 Juni 135, Sekr. C2 10623 Berlin Germany
| | - J Niklas Hausmann
- Department of Chemistry: Metalorganics and Inorganic Materials, Technische Universität Berlin Straße des 17 Juni 135, Sekr. C2 10623 Berlin Germany
| | - Stefan Mebs
- Fachbereich Physik, Freie Universität Berlin Arnimallee 14 Berlin 14195 Germany
| | - Johannes Schmidt
- Department of Chemistry: Functional Materials, Technische Universität Berlin Hardenbergstraße 40 Berlin 10623 Germany
| | - Ivelina Zaharieva
- Fachbereich Physik, Freie Universität Berlin Arnimallee 14 Berlin 14195 Germany
| | - Konstantin Laun
- Institut für Chemie, Max-Volmar-Laboratorium für Biophysikalische Chemie, Technische Universität Berlin Straße des 17 Juni 135 Berlin 10623 Germany
| | - Ingo Zebger
- Institut für Chemie, Max-Volmar-Laboratorium für Biophysikalische Chemie, Technische Universität Berlin Straße des 17 Juni 135 Berlin 10623 Germany
| | - Holger Dau
- Fachbereich Physik, Freie Universität Berlin Arnimallee 14 Berlin 14195 Germany
| | - Prashanth W Menezes
- Department of Chemistry: Metalorganics and Inorganic Materials, Technische Universität Berlin Straße des 17 Juni 135, Sekr. C2 10623 Berlin Germany
| | - Matthias Driess
- Department of Chemistry: Metalorganics and Inorganic Materials, Technische Universität Berlin Straße des 17 Juni 135, Sekr. C2 10623 Berlin Germany
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22
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Kraal P, van Genuchten CM, Lenstra WK, Behrends T. Coprecipitation of Phosphate and Silicate Affects Environmental Iron (Oxyhydr)Oxide Transformations: A Gel-Based Diffusive Sampler Approach. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:12795-12802. [PMID: 32885962 DOI: 10.1021/acs.est.0c02352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Sorption of nutrients such as phosphate (P) and silicate (Si) by ferric iron (oxyhydr)oxides (FeOx) modulates nutrient mobility and alters the structure and reactivity of the FeOx. We investigated the impact of these interactions on FeOx transformations using a novel approach with samplers containing synthetic FeOx embedded in diffusive hydrogels. The FeOx were prepared by Fe(III) hydrolysis and Fe(II) oxidation, in the absence and presence of P or Si. Coprecipitation of P or Si during synthesis altered the structure of Fe precipitates and, in the case of Fe(II) oxidation, lepidocrocite was (partly) substituted by poorly ordered FeOx. The pure and P- or Si-bearing FeOx were deployed in (i) freshwater sediment rich in dissolved Fe(II) and P and (ii) marine sediment with sulfidic pore water. Iron(II)-catalyzed crystallization of poorly ordered FeOx was negligible, likely due to surface passivation by adsorption of dissolved P. Reaction with dissolved sulfide was modulated by diffusion limitations and therefore the extent of sulfidation was the lowest for poorly ordered FeOx with high reactivity toward sulfide that created temporary, local sulfide depletion (Fh < Lp). We show that coprecipitation-induced changes in the FeOx structure affect coupled iron-nutrient cycling in aquatic ecosystems. The gel-based method enriches our geochemical toolbox by enabling detailed characterization of target phases under natural conditions.
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Affiliation(s)
- Peter Kraal
- Department of Earth Sciences-Geochemistry, Faculty of Geosciences, Utrecht University, P.O. Box 80021, 3508 TA Utrecht, The Netherlands
- NIOZ Royal Netherlands Institute for Sea Research, Department of Ocean Systems,1790 AB Den Burg, and Utrecht University, The Netherlands
| | - Case M van Genuchten
- Department of Earth Sciences-Geochemistry, Faculty of Geosciences, Utrecht University, P.O. Box 80021, 3508 TA Utrecht, The Netherlands
| | - Wytze K Lenstra
- Department of Earth Sciences-Geochemistry, Faculty of Geosciences, Utrecht University, P.O. Box 80021, 3508 TA Utrecht, The Netherlands
| | - Thilo Behrends
- Department of Earth Sciences-Geochemistry, Faculty of Geosciences, Utrecht University, P.O. Box 80021, 3508 TA Utrecht, The Netherlands
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23
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Pi K, Xie X, Ma T, Su C, Li J, Wang Y. Arsenic immobilization by in-situ iron coating for managed aquifer rehabilitation. WATER RESEARCH 2020; 181:115859. [PMID: 32438118 DOI: 10.1016/j.watres.2020.115859] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 04/17/2020] [Accepted: 04/21/2020] [Indexed: 06/11/2023]
Abstract
A long-lasting challenge in eliminating the worldwide impact of geogenic arsenic (As)-contaminated groundwater is the development of efficient, in-situ treatment technologies that are applicable in decentralized and rural areas. Here we present a managed aquifer rehabilitation (MAR) approach based on the in-situ creation of Fe-oxide scavengers for remediating As-contaminated groundwater. The Fe-oxide coatings on sediment surfaces were generated via periodic injection of Fe2+ and ClO- solutions into an As-affected sandy aquifer at the Datong Basin, northern China for 25 days. This treatment prompted the buildup of weakly alkaline/circumneutral and oxidizing conditions to enhance As(III) oxidation in the target aquifer. Dissolved As concentrations decreased from the initial average 78.0 to 9.8 μg/L over the 25-d amendment. Sediment imaging by scanning electron microscope-X-ray energy dispersive spectroscopy confirms the deposition of Fe-rich precipitates on sediment surfaces with the simultaneous retention of As, and high density electrical tomography suggests the occurrence of such a process throughout the target zone. Further X-ray diffraction analysis and sequential chemical extraction reveal that the neo-formed Fe minerals comprised both poorly crystalline (e.g., ferrihydrite) and better crystalline (e.g., goethite) Fe oxides. The process-based reactive-transport modeling for the variations of As species in the treated groundwater supports that the new Fe-oxide minerals, most probably goethite, acted as efficient removers of aqueous As. The low As level of ∼10 μg/L was maintained during the following 215-d monitoring, demonstrating the long effectiveness of the MAR approach. This study highlights the feasibility of As immobilization by manipulating in-situ Fe-oxide coating on sandy sediments at the pilot scale. The MAR technology may be applicable for As-affected aquifers with controlled oxidizing conditions in the Datong Basin and likely other high-As regions with similar hydrogeochemical settings.
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Affiliation(s)
- Kunfu Pi
- School of Environmental Studies & State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China
| | - Xianjun Xie
- School of Environmental Studies & State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China
| | - Teng Ma
- School of Environmental Studies & State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China
| | - Chunli Su
- School of Environmental Studies & State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China
| | - Junxia Li
- School of Environmental Studies & State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China
| | - Yanxin Wang
- School of Environmental Studies & State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, China.
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24
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Sheng A, Li X, Arai Y, Ding Y, Rosso KM, Liu J. Citrate Controls Fe(II)-Catalyzed Transformation of Ferrihydrite by Complexation of the Labile Fe(III) Intermediate. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:7309-7319. [PMID: 32421322 DOI: 10.1021/acs.est.0c00996] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Ferrihydrite (Fh) is generally associated with dissolved organic matter (DOM) in natural environments due to a strong sorption affinity at circumneutral pH and its high specific surface area. In suboxic conditions, aqueous Fe(II) (Fe(II)aq) can catalyze transformation of Fh into more stable crystalline Fe(III) phases, but how DOM influences the transformation kinetics and pathway is still unclear. Using citrate as a surrogate, we have examined Fh transformation with 1 mM Fe(II)aq and 0-60 μM citrate at pH 7.2. We focus on quantifying the time-dependent concentrations of sorbed Fe(II), structural Fe(II), and a key intermediate species, labile Fe(III) (Fe(III)labile), resulting from interfacial electron transfer (IET), and how these species correlate with the evolution of lepidocrocite (Lp), magnetite (Mt), and goethite (Gt) products. Low concentrations of citrate significantly impact the proportions of Lp/Gt, and the collective results reveal that its effect is primarily through its ability to complex labile Fe(III) and thereby disrupt polymerization into product crystallites, as opposed to modifying the surface properties of Fh or inhibiting IET. The emergence of a Mt coprecipitate is observed in the transformation experiments with 5-10 μM citrate, when the Fe(II)/Fe(III)labile ratio on/near the Fh surface is close to 0.5, the stoichiometric Fe(II)/Fe(III) ratio in Mt. At the molecular level, the findings suggest that citrate, and by extension DOM, can modify the relative rates of olation and oxolation reactions that assemble labile Fe(III) into various product minerals.
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Affiliation(s)
- Anxu Sheng
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Xiaoxu Li
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yuji Arai
- Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, 1102 South Goodwin Avenue, Urbana, Illinois 61801, United States
| | - Yuefei Ding
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Kevin M Rosso
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Juan Liu
- The Key Laboratory of Water and Sediment Sciences, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
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25
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Berens MJ, Hofstetter TB, Bolotin J, Arnold WA. Assessment of 2,4-Dinitroanisole Transformation Using Compound-Specific Isotope Analysis after In Situ Chemical Reduction of Iron Oxides. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:5520-5531. [PMID: 32275413 DOI: 10.1021/acs.est.9b07616] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Ferrous iron-bearing minerals are important reductants in the contaminated subsurface, but their availability for the reduction of anthropogenic pollutants is often limited by competition with other electron acceptors including microorganisms and poor accessibility to Fe(II) in complex hydrogeologic settings. The supply of external electron donors through in situ chemical reduction (ISCR) has been proposed as one remediation approach, but the quantification of pollutant transformation is complicated by the perturbations introduced to the subsurface by ISCR. Here, we evaluate the application of compound specific isotope analysis (CSIA) for monitoring the reduction of 2,4-dinitroanisole (DNAN), a component of insensitive munitions formulations, by mineral-bound Fe(II) generated through ISCR of subsurface material from two field sites. Electron balances from laboratory experiments in batch and column reactors showed that 3.6% to 11% of the total Fe in the sediments was available for the reduction of DNAN and its partially reduced intermediates after dithionite treatment. The extent of DNAN reduction was successfully quantified from its N isotope fractionation measured in the column effluent based on the derivation of a N isotope enrichment factor, εN, derived from a comprehensive series of isotope fractionation experiments with numerous Fe(II)-bearing minerals as well as dithionite-reduced subsurface materials. Our observations illustrate the utility of CSIA as a robust approach to evaluate the success of in situ remediation through abiotic contaminant reduction.
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Affiliation(s)
- Matthew J Berens
- Department of Civil, Environmental, and Geo- Engineering, University of Minnesota, 500 Pillsbury Drive SE, Minneapolis, Minnesota 55455-0116, United States
| | - Thomas B Hofstetter
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Environmental Chemistry, Überlandstrasse 133, CH-8600 Dübendorf , Switzerland
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, CH-8092 Zürich, Switzerland
| | - Jakov Bolotin
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Environmental Chemistry, Überlandstrasse 133, CH-8600 Dübendorf , Switzerland
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, CH-8092 Zürich, Switzerland
| | - William A Arnold
- Department of Civil, Environmental, and Geo- Engineering, University of Minnesota, 500 Pillsbury Drive SE, Minneapolis, Minnesota 55455-0116, United States
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Thomas AN, Eiche E, Göttlicher J, Steininger R, Benning LG, Freeman HM, Tobler DJ, Mangayayam M, Dideriksen K, Neumann T. Effects of metal cation substitution on hexavalent chromium reduction by green rust. GEOCHEMICAL TRANSACTIONS 2020; 21:2. [PMID: 32060743 PMCID: PMC7020553 DOI: 10.1186/s12932-020-00066-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 02/04/2020] [Indexed: 06/06/2023]
Abstract
Chromium contamination is a serious environmental issue in areas affected by leather tanning and metal plating, and green rust sulfate has been tested extensively as a potential material for in situ chemical reduction of hexavalent chromium in groundwater. Reported products and mechanisms for the reaction have varied, most likely because of green rust's layered structure, as reduction at outer and interlayer surfaces might produce different reaction products with variable stabilities. Based on studies of Cr(III) oxidation by biogenic Mn (IV) oxides, Cr mobility in oxic soils is controlled by the solubility of the Cr(III)-bearing phase. Therefore, careful engineering of green rust properties, i.e., crystal/particle size, morphology, structure, and electron availability, is essential for its optimization as a remediation reagent. In the present study, pure green rust sulfate and green rust sulfate with Al, Mg and Zn substitutions were synthesized and reacted with identical chromate (CrO42-) solutions. The reaction products were characterized by X-ray diffraction, pair distribution function analysis, X-ray absorption spectroscopy and transmission electron microscopy and treated with synthetic δ-MnO2 to assess how easily Cr(III) in the products could be oxidized. It was found that Mg substitution had the most beneficial effect on Cr lability in the product. Less than 2.5% of the Cr(III) present in the reacted Mg-GR was reoxidized by δ-MnO2 within 14 days, and the particle structure and Cr speciation observed during X-ray scattering and absorption analyses of this product suggested that Cr(VI) was reduced in its interlayer. Reduction in the interlayer lead to the linkage of newly-formed Cr(III) to hydroxyl groups in the adjacent octahedral layers, which resulted in increased structural coherency between these layers, distinctive rim domains, sequestration of Cr(III) in insoluble Fe oxide bonding environments resistant to reoxidation and partial transformation to Cr(III)-substituted feroxyhyte. Based on the results of this study of hexavalent chromium reduction by green rust sulfate and other studies, further improvements can also be made to this remediation technique by reacting chromate with a large excess of green rust sulfate, which provides excess Fe(II) that can catalyze transformation to more crystalline iron oxides, and synthesis of the reactant under alkaline conditions, which has been shown to favor chromium reduction in the interlayer of Fe(II)-bearing phyllosilicates.
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Affiliation(s)
- Andrew N Thomas
- Institute of Applied Geosciences, Karlsruhe Institute of Technology, 76137, Karlsruhe, Germany.
| | - Elisabeth Eiche
- Institute of Applied Geosciences, Karlsruhe Institute of Technology, 76137, Karlsruhe, Germany
| | - Jörg Göttlicher
- Institute of Synchrotron Radiation, Karlsruhe Institute of Technology, 76344, Eggenstein-Leopoldshafen, Germany
| | - Ralph Steininger
- Institute of Synchrotron Radiation, Karlsruhe Institute of Technology, 76344, Eggenstein-Leopoldshafen, Germany
| | - Liane G Benning
- GFZ German Research Center for Geosciences, Telegrafenberg, 14473, Potsdam, Germany
- Department of Earth Sciences, Free University of Berlin, 12249, Berlin, Germany
| | - Helen M Freeman
- GFZ German Research Center for Geosciences, Telegrafenberg, 14473, Potsdam, Germany
- School of Chemical and Processing Engineering, University of Leeds, Leeds, LS29JT, UK
| | - Dominique J Tobler
- Nano-Science Center, Department of Chemistry, University of Copenhagen, 2100, Copenhagen, Denmark
| | - Marco Mangayayam
- Nano-Science Center, Department of Chemistry, University of Copenhagen, 2100, Copenhagen, Denmark
| | - Knud Dideriksen
- Nano-Science Center, Department of Chemistry, University of Copenhagen, 2100, Copenhagen, Denmark
| | - Thomas Neumann
- Department of Applied Geosciences, Technical University of Berlin, 10587, Berlin, Germany
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27
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Liu Y, Tian Y, Zhang R, Guo H, Zhao W, Huang J. Corrosion behavior and mechanism of ductile iron with different degrees of deterioration of cement mortar lining in reclaimed water pipelines. RSC Adv 2020; 10:39627-39639. [PMID: 35515357 PMCID: PMC9057434 DOI: 10.1039/d0ra08042j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 10/12/2020] [Indexed: 11/21/2022] Open
Abstract
The influence of the degradation degree of cement mortar lining on the corrosion of the ductile iron pipe in reclaimed water.
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Affiliation(s)
- Yunhui Liu
- School of Environmental Science and Engineering
- Tianjin University
- Tianjin 300350
- China
| | - Yimei Tian
- School of Environmental Science and Engineering
- Tianjin University
- Tianjin 300350
- China
| | - Rufang Zhang
- School of Environmental Science and Engineering
- Tianjin University
- Tianjin 300350
- China
| | - Hao Guo
- The Institute of Seawater Desalination and Multipurpose Utilization
- MNR (Tianjin)
- Tianjin 300192
- China
| | - Weigao Zhao
- School of Environmental Science and Engineering
- Tianjin University
- Tianjin 300350
- China
| | - Jianjun Huang
- School of Environmental Science and Engineering
- Tianjin University
- Tianjin 300350
- China
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28
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Karimian N, Burton ED, Johnston SG. Antimony speciation and mobility during Fe(II)-induced transformation of humic acid-antimony(V)-iron(III) coprecipitates. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 254:113112. [PMID: 31479811 DOI: 10.1016/j.envpol.2019.113112] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 08/01/2019] [Accepted: 08/23/2019] [Indexed: 06/10/2023]
Abstract
Antimony, as the Sb(V) species, often occurs in oxic soils and sediments as coprecipitates with poorly-crystalline Fe(III)-bearing minerals. It is common for these Sb(V)-Fe(III) coprecipitates to also contain varying quantities of co-occurring humic acid (HA). When exposed to reducing conditions, the production of Fe(II) may cause the initial metastable HA-Sb(V)-Fe(III) phases to undergo rapid transformations to more stable phases, thereby potentially influencing the geochemical behavior of coprecipitated Sb(V). However, little is known about the impacts of this transformation on the mobility and speciation of Sb. In this study, we reacted synthetic HA-Sb(V)-Fe(III) coprecipitates (Fe:Sb ratio = 4, and C:Fe molar ratios = 0, 0.3, 0.8 and 1.3) with 0, 1 or 10 mM Fe(II) under O2-free conditions at pH 7.0 for 15 days. Fe K-edge EXAFS spectroscopy revealed that solid-phase Fe(III) in the initial coprecipitates contained a mixture of ∼4/5 ferrihydrite (Fe10O14(OH)2) and ∼1/5 tripuhyite (FeSbO4), regardless of the corresponding amount of coprecipitated HA. Tripuhyite persisted throughout the full experiment duration, while ferrihydrite was partially replaced by goethite (FeOOH) when either 1 or 10 mM Fe(II)aq was added to the coprecipitates. The greatest level of goethite formation (∼55% of solid-phase Fe) was observed in the HA-free/10 mM Fe(II)aq treatment, with ferrihydrite transformation being partially attenuated at higher levels of HA. Mobilisation of aqueous Sb was the greatest for 1 mM Fe(II) treatments at high HA:Fe ratios. Sb K-edge XANES spectroscopy showed that the largest reduction of Sb(V) to Sb(III) (∼37%) and the greatest repartitioning of Sb to the mineral surface (∼7.9-9.8%) occurred in the coprecipitates with the highest HA contents in the presence of 10 mM Fe(II). The results indicate that the amount of HA in HA-Sb(V)-Fe(III) coprecipitates can greatly influence mobility and speciation of Sb in Fe(II)-rich conditions. The results of this study provide new insights into alterations in Sb mobility and retention in response to Fe cycling under organic matter-rich reducing conditions.
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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
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Narayanan S, Firlar E, Rasul MG, Foroozan T, Farajpour N, Covnot L, Shahbazian-Yassar R, Shokuhfar T. On the structure and chemistry of iron oxide cores in human heart and human spleen ferritins using graphene liquid cell electron microscopy. NANOSCALE 2019; 11:16868-16878. [PMID: 31482911 DOI: 10.1039/c9nr01541h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Ferritin is a protein that regulates the iron ions in humans by storing them in the form of iron oxides. Despite extensive efforts to understand the ferritin iron oxide structures, it is still not clear how ferritin proteins with a distinct light (L) and heavy (H) chain subunit ratio impact the biomineralization process. In situ graphene liquid cell-transmission electron microscopy (GLC-TEM) provides an indispensable platform to study the atomic structure of ferritin mineral cores in their native liquid environment. In this study, we report differences in the iron oxide formation in human spleen ferritins (HSFs) and human heart ferritins (HHFs) using in situ GLC-TEM. Scanning transmission electron microscopy (STEM) along with selected area electron diffraction (SAED) of the mineral core and electron energy loss spectroscopy (EELS) analyses enabled the visualization of morphologies, crystal structures and the chemistry of iron oxide cores in HSFs and HHFs. Our study revealed the presence of metastable ferrihydrite (5Fe2O3·9H2O) as a dominant phase in hydrated HSFs and HHFs, while a stable hematite (α-Fe2O3) phase predominated in non-hydrated HSFs and HHFs. In addition, a higher Fe3+/Fe2+ ratio was found in HHFs in comparison with HSFs. This study provides new understanding on iron-oxide phases that exist in hydrated ferritin proteins from different human organs. Such new insights are needed to map ferritin biomineralization pathways and possible correlations with various iron-related disorders in humans.
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Affiliation(s)
- Surya Narayanan
- University of Illinois at Chicago, Department of Bioengineering, Chicago, IL 60607, USA.
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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. THE SCIENCE OF THE TOTAL ENVIRONMENT 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] [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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Stolze L, Zhang D, Guo H, Rolle M. Model-Based Interpretation of Groundwater Arsenic Mobility during in Situ Reductive Transformation of Ferrihydrite. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:6845-6854. [PMID: 31117535 DOI: 10.1021/acs.est.9b00527] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Arsenic (As) release and mobility in groundwater is coupled to the iron (Fe) cycling and the associated transformation of Fe-oxides present in sediments. Recent in situ experiments have provided observations on arsenic mobilization and co-occurring reductive mineral transformation when placing As-loaded ferrihydrite-coated sand for 80 days in wells of an As-contaminated aquifer of Northern China. However, the complex temporal change in solid-associated arsenic and the multiple geochemical processes occurring when the flowing groundwater contacts the As-loaded ferrihydrite-coated sand hamper a detailed evaluation of the experimental data set. In this study, we develop a modeling approach that allows a quantitative interpretation of arsenic release and ferrihydrite transformation observed during the in situ experiments. The model accounts for the interplay of abiotic and biotic geochemical processes (i.e., surface complexation, reductive dissolution, formation of secondary iron minerals, and arsenic sequestration into the newly formed minerals) involved in the transformation of Fe-oxides and controlling arsenic mobility. The results show the capability of the proposed approach to reproduce the temporal trends of solid arsenic and ferrihydrite concentrations, as well as the spatial variability of mineral transformation, observed in different wells using a common set of surface complexation parameters and kinetic rate constants. The simulation outcomes allowed us to disentangle the specific contribution of the different mechanisms controlling the release of arsenic. It was possible to identify an initial rapid but minor release of As (13-23% of the initial surface concentration) due to desorption from ferrihydrite, as well as the reduction of adsorbed As(V) to As(III) upon contact with the flowing anoxic groundwater. Successively, reductive dissolution of ferrihydrite caused the decrease of the amount of the Fe mineral phase and led to a major depletion of solid-associated arsenic. The produced Fe(II) catalyzed the ferrihydrite conversion into more crystalline Fe(III) oxides (i.e., lepidocrocite and goethite) through Ostwald ripening, and resulted in the formation of siderite and mackinawite upon reaction with carbonates and sulfides naturally present in the groundwater. The model results also showed that, whereas the decrease in surface sites during reductive dissolution of ferrihydrite promoted arsenic mobilization, the mineral transformation limited As release through its sequestration into the newly formed secondary mineral phases.
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Affiliation(s)
- Lucien Stolze
- Department of Environmental Engineering , Technical University of Denmark , Miljøvej, Building 115, 2800 Kgs . Lyngby , Denmark
| | - Di Zhang
- School of Water Resources and Environment , China University of Geosciences , Beijing 100083 , China
| | - Huaming Guo
- School of Water Resources and Environment , China University of Geosciences , Beijing 100083 , China
| | - Massimo Rolle
- Department of Environmental Engineering , Technical University of Denmark , Miljøvej, Building 115, 2800 Kgs . Lyngby , Denmark
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Li G, Hao H, Zhuang Y, Wang Z, Shi B. Powdered activated carbon enhanced Manganese(II) removal by chlorine oxidation. WATER RESEARCH 2019; 156:287-296. [PMID: 30925375 DOI: 10.1016/j.watres.2019.03.027] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 02/24/2019] [Accepted: 03/15/2019] [Indexed: 06/09/2023]
Abstract
Chlorine is not effective in the oxidative removal of soluble manganese(II) ions at neutral pH. Powdered activated carbon (PAC) also has a very limited capacity for Mn(II) removal through adsorption in drinking water treatment practice. This study explored the combined use of PAC and chlorine for Mn(II) removal and found that PAC dramatically catalyzed Mn(II) oxidation by chlorine under diverse conditions. At a dose as low as 5.0 mg/L, two different commercial PACs increased Mn(II) oxidation rate by two orders of magnitude respectively and reduced Mn(II) concentration from 200 μg/L to < 10 μg/L in tens of minutes. First-order kinetics with respect to aqueous Mn(II) concentration were observed. Typically, homogeneous Mn(II) oxidation by chlorine depends strongly on alkaline pH. In the presence of PAC, however, the reaction was still rather fast at pH 6.0. Increasing PAC doses linearly increased Mn(II) oxidation rate, indicating that the reaction was highly PAC surface active sites dependent. The efficacy of PAC was further corroborated in removing Mn(II) from natural water. SEM-EDS and XPS demonstrated that a MnO2 coating was formed on PAC surface after reaction, which resulted from heterogeneous oxidation of Mn(II) on PAC surface rather than the precipitation of Mn oxides formed through homogeneous oxidation in solution. Adsorption of free Mn(II) ions onto PAC surface was proved to directly correlate with Mn(II) oxidation rate. Two kinds of electron transfer pathways from adsorbed Mn(II) species to chlorine, enhanced by surface-complexation and electrically-conductive carbon surface respectively, were hypothesized.
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Affiliation(s)
- Guiwei Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Haotian Hao
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Yuan Zhuang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Ziqiao Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
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He L, Xie L, Wang D, Li W, Fortner JD, Li Q, Duan Y, Shi Z, Liao P, Liu C. Elucidating the Role of Sulfide on the Stability of Ferrihydrite Colloids under Anoxic Conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:4173-4184. [PMID: 30870594 DOI: 10.1021/acs.est.8b05694] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
While the reaction mechanisms between ferrihydrite and sulfide are well-documented, the role of redox reactions on the particle-particle stability of ferrihydrite colloids is largely overlooked. Such reactions are critical for a number of (bio)geochemical processes governing ferrihydrite-based colloid processing and their associated role in nutrient and contaminant subsurface dynamics. Taking a fundamental colloid chemistry approach, along with a complementary suite of characterization techniques, here, we explore the stability mechanisms of ferrihydrite colloids over a wide range of environmentally relevant sulfide concentrations at pH 6.0. Results show that sulfide lowered the stability of both ferrihydrite colloids in a concentration-dependent fashion. At lower sulfide concentrations (15.6-62.5 μM), ferrihydrite colloids are apparently stable, but their critical coagulation concentration (CCC) in NaCl linearly decreases with increasing sulfide concentration. This is attributed to the formation of negatively charged elemental sulfur (S(0)) nanoparticles on the surfaces of positively charged ferrihydrite, intensifying the electrostatic attractions between oppositely charged regions on adjacent ferrihydrite surfaces. Further increasing sulfide concentration generates more S(0) attaching to the ferrihydrite surface. This results in effective surface charge neutralization and then subsequent charge reversal, leading to extensive aggregation of ferrihydrite (core) colloids. Interestingly, for the ferrihydrite colloids with higher hydrodynamic diameter, aggregation rates linearly decreases with increasing sulfide concentration from 156.3 to 312.5 μM, which is likely due to the formation of substantial amounts of negatively charged S(0) and FeS. Findings highlight the significance of sulfidation products in controlling the stability of ferrihydrite colloids in sulfidic environments.
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Affiliation(s)
- Leiyu He
- Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering , Southern University of Science and Technology , Shenzhen , 518055 , P. R. China
| | - Lin Xie
- Department of Physics , Southern University of Science and Technology , Shenzhen , 518055 , P. R. China
| | - Dengjun Wang
- National Research Council Resident Research Associate , United States Environmental Protection Agency , Ada , Oklahoma 74820 , United States
| | - Wenlu Li
- Department of Energy, Environmental and Chemical Engineering , Washington University in St. Louis , St. Louis , Missouri 63130 , United States
| | - John D Fortner
- Department of Energy, Environmental and Chemical Engineering , Washington University in St. Louis , St. Louis , Missouri 63130 , United States
| | - Qianqian Li
- Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering , Southern University of Science and Technology , Shenzhen , 518055 , P. R. China
| | - Yanhua Duan
- Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering , Southern University of Science and Technology , Shenzhen , 518055 , P. R. China
| | - Zhenqing Shi
- School of Environment and Energy , South China University of Technology , Guangzhou , Guangdong 510006 , P. R. China
| | - Peng Liao
- Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering , Southern University of Science and Technology , Shenzhen , 518055 , P. R. China
- 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
| | - Chongxuan Liu
- Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering , Southern University of Science and Technology , Shenzhen , 518055 , P. R. China
- 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
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Aeppli M, Kaegi R, Kretzschmar R, Voegelin A, Hofstetter TB, Sander M. Electrochemical Analysis of Changes in Iron Oxide Reducibility during Abiotic Ferrihydrite Transformation into Goethite and Magnetite. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:3568-3578. [PMID: 30758207 DOI: 10.1021/acs.est.8b07190] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Electron transfer to ferric iron in (oxyhydr-)oxides (hereafter iron oxides) is a critical step in many processes that are central to the biogeochemical cycling of elements and to pollutant dynamics. Understanding these processes requires analytical approaches that allow for characterizing the reactivity of iron oxides toward reduction under controlled thermodynamic boundary conditions. Here, we used mediated electrochemical reduction (MER) to follow changes in iron oxide reduction extents and rates during abiotic ferrous iron-induced transformation of six-line ferrihydrite. Transformation experiments (10 mM ferrihydrite-FeIII) were conducted over a range of solution conditions (pHtrans = 6.50 to 7.50 at 5 mM Fe2+ and for pHtrans = 7.00 also at 1 mM Fe2+) that resulted in the transformation of ferrihydrite into thermodynamically more stable goethite or magnetite. The changes in iron oxide mineralogy during the transformations were quantified using X-ray diffraction analysis. MER measurements on iron oxide suspension aliquots collected during the transformations were performed over a range of pHMER at constant applied reduction potential. The extents and rates of iron oxide reduction in MER decreased with decreasing reaction driving force resulting from both increasing pHMER and increasing transformation of ferrihydrite into thermodynamically more stable iron oxides. We show that the decreases in iron oxide reduction extents and rates during ferrihydrite transformations can be linked to the concurrent changes in iron oxide mineralogy.
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Affiliation(s)
- Meret Aeppli
- Institute of Biogeochemistry and Pollutant Dynamics , ETH Zürich , 8092 Zürich , Switzerland
- Swiss Federal Institute of Aquatic Science and Technology (Eawag) , 8600 Dübendorf , Switzerland
| | - Ralf Kaegi
- Swiss Federal Institute of Aquatic Science and Technology (Eawag) , 8600 Dübendorf , Switzerland
| | - Ruben Kretzschmar
- Institute of Biogeochemistry and Pollutant Dynamics , ETH Zürich , 8092 Zürich , Switzerland
| | - Andreas Voegelin
- Swiss Federal Institute of Aquatic Science and Technology (Eawag) , 8600 Dübendorf , Switzerland
| | - Thomas B Hofstetter
- Institute of Biogeochemistry and Pollutant Dynamics , ETH Zürich , 8092 Zürich , Switzerland
- Swiss Federal Institute of Aquatic Science and Technology (Eawag) , 8600 Dübendorf , Switzerland
| | - Michael Sander
- Institute of Biogeochemistry and Pollutant Dynamics , ETH Zürich , 8092 Zürich , Switzerland
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Visualizing the iron atom exchange front in the Fe(II)-catalyzed recrystallization of goethite by atom probe tomography. Proc Natl Acad Sci U S A 2019; 116:2866-2874. [PMID: 30733289 DOI: 10.1073/pnas.1816620116] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The autocatalytic redox interaction between aqueous Fe(II) and Fe(III)-(oxyhydr)oxide minerals such as goethite and hematite leads to rapid recrystallization marked, in principle, by an atom exchange (AE) front, according to bulk iron isotopic tracer studies. However, direct evidence for this AE front has been elusive given the analytical challenges of mass-resolved imaging at the nanoscale on individual crystallites. We report successful isolation and characterization of the AE front in goethite microrods by 3D atom probe tomography (APT). The microrods were reacted with Fe(II) enriched in tracer 57Fe at conditions consistent with prior bulk studies. APT analyses and 3D reconstructions on cross-sections of the microrods reveal an AE front that is spatially heterogeneous, at times penetrating several nanometers into the lattice, in a manner consistent with defect-accelerated exchange. Evidence for exchange along microstructural domain boundaries was also found, suggesting another important link between exchange extent and initial defect content. The findings provide an unprecedented view into the spatial and temporal characteristics of Fe(II)-catalyzed recrystallization at the atomic scale, and substantiate speculation regarding the role of defects controlling the dynamics of electron transfer and AE interaction at this important redox interface.
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Penas D, Pereira AS, Tavares P. Direct Evidence for Ferrous Ion Oxidation and Incorporation in the Absence of Oxidants by Dps from Marinobacter hydrocarbonoclasticus. Angew Chem Int Ed Engl 2019; 58:1013-1018. [PMID: 30481405 DOI: 10.1002/anie.201809584] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 11/15/2018] [Indexed: 11/09/2022]
Abstract
Dps proteins (DNA-binding protein from starved cells) are hollow-sphere-shaped, dodecameric enzymes found in bacteria and archaeal species. They can oxidize ferrous iron in a controlled manner using hydrogen peroxide or molecular oxygen as co-substrate, and most of them confer physical protection through DNA binding. Oxidized iron is stored, as a mineral core, in a central cavity. Direct evidence is now provided that, furthermore, Dps proteins containing small mineral cores can oxidize and mineralize toxic ferrous ions in anaerobic conditions and in the absence of any additional aqueous oxidant co-substrate. Dps proteins containing cores of 24 irons per dodecamer can oxidize about 5 ferrous irons per dodecamer, with that number approximately doubling for protein particles containing in average 96 irons per protein. This additional activity carries importance as it can be a detoxification mechanism present during anaerobic or oxygen-limited growth conditions.
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Affiliation(s)
- Daniela Penas
- Molecular Biophysics Lab., UCIBIO/Requimte, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal
| | - Alice S Pereira
- Molecular Biophysics Lab., UCIBIO/Requimte, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal
| | - Pedro Tavares
- Molecular Biophysics Lab., UCIBIO/Requimte, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal
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37
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Penas D, Pereira AS, Tavares P. Direct Evidence for Ferrous Ion Oxidation and Incorporation in the Absence of Oxidants by Dps from Marinobacter hydrocarbonoclasticus. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201809584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Daniela Penas
- Molecular Biophysics Lab.UCIBIO/RequimteDepartamento de QuímicaFaculdade de Ciências e TecnologiaUniversidade Nova de Lisboa 2829-516 Caparica Portugal
| | - Alice S. Pereira
- Molecular Biophysics Lab.UCIBIO/RequimteDepartamento de QuímicaFaculdade de Ciências e TecnologiaUniversidade Nova de Lisboa 2829-516 Caparica Portugal
| | - Pedro Tavares
- Molecular Biophysics Lab.UCIBIO/RequimteDepartamento de QuímicaFaculdade de Ciências e TecnologiaUniversidade Nova de Lisboa 2829-516 Caparica Portugal
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38
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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. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:12316-12326. [PMID: 30991468 DOI: 10.1021/acs.est.8b03206] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [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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39
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Products of Hexavalent Chromium Reduction by Green Rust Sodium Sulfate and Associated Reaction Mechanisms. SOIL SYSTEMS 2018. [DOI: 10.3390/soilsystems2040058] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The efficacy of in vitro Cr(VI) reduction by green rust sulfate suggests that this mineral is potentially useful for remediation of Cr-contaminated groundwater. Previous investigations studied this reaction but did not sufficiently characterize the intermediates and end products at chromate (CrO42−) concentrations typical of contaminant plumes, hindering identification of the dominant reaction mechanisms under these conditions. In this study, batch reactions at varying chromate concentrations and suspension densities were performed and the intermediate and final products of this reaction were analyzed using X-ray absorption spectroscopy and electron microscopy. This reaction produces particles that maintain the initial hexagonal morphology of green rust but have been topotactically transformed into a poorly crystalline Fe(III) oxyhydroxysulfate and are coated by a Cr (oxy) hydroxide layer that results from chromate reduction at the surface. Recent studies of the behavior of Cr(III) (oxy) hydroxides in soils have revealed that reductive transformation of CrO42− is reversible in the presence of Mn(IV) oxides, limiting the applicability of green rust for Cr remediation in some soils. The linkage of Cr redox speciation to existing Fe and Mn biogeochemical cycles in soils implies that modification of green rust particles to produce an insoluble, Cr(III)-bearing Fe oxide product may increase the efficacy of this technique.
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Guan G, Wang X, Li B, Zhang W, Cui Z, Lu X, Zou R, Hu J. "Transformed" Fe 3S 4 tetragonal nanosheets: a high-efficiency and body-clearable agent for magnetic resonance imaging guided photothermal and chemodynamic synergistic therapy. NANOSCALE 2018; 10:17902-17911. [PMID: 30226246 DOI: 10.1039/c8nr06507a] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
To retain the agents in tumors for cancer diagnosis and therapy, and then to remove them from the body, are key for the clinical applications of ideal inorganic theranostic agents. To meet these needs, we have developed a transformed theranostic platform, employing PVP coated Fe3S4 tetragonal nanosheets (TNSs), which could effectively accumulate in the tumor under magnetic targeting, whilst gradually transforming to small particles (∼5 nm) over three weeks. These were then effectively excreted from the body in normal physiological conditions after exerting their therapeutic effect. The aqueous dispersion of PVP coated Fe3S4 TNSs had an intense near-infrared absorption, excellent photothermal conversion efficiency (64.3%) and great T2 weighted magnetic resonance imaging properties (71.3 mM-1 S-1). In addition, Fe3S4 TNSs could realize a synergistic photothermal therapy (PTT)/chemodynamic therapy (CDT), because the localized heat produced by PTT from the defect-rich structure could enhance the Fenton process by utilizing the overproduced H2O2 in the tumor microenvironment, and in return, the produced ˙OH could inhibit tumor growth and recurrence after PPT. We thus developed a high-efficiency inorganic theranostic platform which was effectively cleared from the body. This will open up a new avenue for the design of inorganic agents for clinical applications in the future.
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Affiliation(s)
- Guoqiang Guan
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China.
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Jubb AM, Eskelsen JR, Yin X, Zheng J, Philben MJ, Pierce EM, Graham DE, Wullschleger SD, Gu B. Characterization of iron oxide nanoparticle films at the air-water interface in Arctic tundra waters. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 633:1460-1468. [PMID: 29758898 DOI: 10.1016/j.scitotenv.2018.03.332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 03/26/2018] [Accepted: 03/27/2018] [Indexed: 06/08/2023]
Abstract
Massive amounts of organic carbon have accumulated in Arctic permafrost and soils due to anoxic and low temperature conditions that limit aerobic microbial respiration. Alternative electron acceptors are thus required for microbes to degrade organic carbon in these soils. Iron or iron oxides have been recognized to play an important role in carbon cycle processes in Arctic soils, although the exact form and role as an electron acceptor or donor remain poorly understood. Here, Arctic biofilms collected during the summers of 2016 and 2017 from tundra surface waters on the Seward Peninsula of western Alaska were characterized with a suite of microscopic and spectroscopic methods. We hypothesized that these films contain redox-active minerals bound to biological polymers. The major components of the films were found to be iron oxide nanoparticle aggregates associated with extracellular polymeric substances. The observed mineral phases varied between films collected in different years with magnetite (Fe2+Fe23+O4) nanoparticles (<5nm) predominantly identified in the 2016 films, while for films collected in 2017 ferrihydrite-like amorphous iron oxyhydroxides were found. While the exact formation mechanism of these Artic iron oxide films remains to be explored, the presence of magnetite and other iron oxide/oxyhydroxide nanoparticles at the air-water interface may represent a previously unknown source of electron acceptors for continual anaerobic microbial respiration of organic carbon within poorly drained Arctic tundra.
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Affiliation(s)
- Aaron M Jubb
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
| | - Jeremy R Eskelsen
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Xiangping Yin
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Jianqiu Zheng
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Michael J Philben
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Eric M Pierce
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - David E Graham
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA; Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Stan D Wullschleger
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA; Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Baohua Gu
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA; Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, TN, USA.
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Stewart SM, Hofstetter TB, Joshi P, Gorski CA. Linking Thermodynamics to Pollutant Reduction Kinetics by Fe 2+ Bound to Iron Oxides. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:5600-5609. [PMID: 29595255 DOI: 10.1021/acs.est.8b00481] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Numerous studies have reported that pollutant reduction rates by ferrous iron (Fe2+) are substantially enhanced in the presence of an iron (oxyhydr)oxide mineral. Developing a thermodynamic framework to explain this phenomenon has been historically difficult due to challenges in quantifying reduction potential ( EH) values for oxide-bound Fe2+ species. Recently, our group demonstrated that EH values for hematite- and goethite-bound Fe2+ can be accurately calculated using Gibbs free energy of formation values. Here, we tested if calculated EH values for oxide-bound Fe2+ could be used to develop a free energy relationship capable of describing variations in reduction rate constants of substituted nitrobenzenes, a class of model pollutants that contain reducible aromatic nitro groups, using data collected here and compiled from the literature. All the data could be described by a single linear relationship between the logarithms of the surface-area-normalized rate constant ( kSA) values and EH and pH values [log( kSA) = - EH/0.059 V - pH + 3.42]. This framework provides mechanistic insights into how the thermodynamic favorability of electron transfer from oxide-bound Fe2+ relates to redox reaction kinetics.
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Affiliation(s)
- Sydney M Stewart
- Department of Civil & Environmental Engineering , Pennsylvania State University , 212 Sackett Building , University Park , Pennsylvania 16802 , United States
| | - Thomas B Hofstetter
- Eawag , Swiss Federal Institute of Aquatic Science and Technology , CH-8600 Dübendorf , Switzerland
- Institute of Biogeochemistry and Pollutant Dynamics , ETH Zurich , CH-8092 Zurich , Switzerland
| | - Prachi Joshi
- Department of Civil & Environmental Engineering , Pennsylvania State University , 212 Sackett Building , University Park , Pennsylvania 16802 , United States
| | - Christopher A Gorski
- Department of Civil & Environmental Engineering , Pennsylvania State University , 212 Sackett Building , University Park , Pennsylvania 16802 , United States
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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: 182] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [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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Park S, Zenobio JE, Lee LS. Perfluorooctane sulfonate (PFOS) removal with Pd 0/nFe 0 nanoparticles: Adsorption or aqueous Fe-complexation, not transformation? JOURNAL OF HAZARDOUS MATERIALS 2018; 342:20-28. [PMID: 28822246 DOI: 10.1016/j.jhazmat.2017.08.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 07/23/2017] [Accepted: 08/01/2017] [Indexed: 06/07/2023]
Abstract
PFOS removal at 6 and 21days (d) when reacted with palladium coated zero valent iron nanoparticles (Pd0/nFe0 NPs) was quantified as a function of pH (3.6, 5.5, and 8.7) and temperature (22, 45 and 70°C). PFOS concentrations were measured in aqueous phases and NP extracts. The greatest PFOS removal occurred at 6 d with the lowest pH and highest temperature; however, recovered PFOS increased at 21 d. Furthermore, neither F- nor SO42- (from SO32- cleavage) generation was observed indicating the absence of PFOS transformation. X-ray diffraction analysis of PFOS-reacted NPs at 45°C revealed generation of FeO(OH) on the NPs at 21 d, which was concomitant with subsequent increases in PFOS recovery. Under anaerobic conditions, strongly adsorbing Fe(OH)3 is formed which can then transform to less sorptive FeO(OH) via Fe2+ catalyzed transformation. In the process of exploring causes for apparent PFOS removal with Pd0/nFe0 NPs, PFOS as well as other perfluoroalkyl acids (PFAAs) were found to form aqueous-phase complexes with Fe(II/III) which can reduce their quantifiable levels. PFOS-Fe complexation was greater with Fe(III) and increased with Fe concentration and decreasing pH. Complexation was also greater for longer chain perfluoroalkyl acids and complexation of PFNA was greater than for PFOS.
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Affiliation(s)
- Saerom Park
- Purdue University, Department of Agronomy, Ecological Science and Engineering, West Lafayette, IN 47907-2054, USA
| | - Jenny E Zenobio
- Purdue University, Department of Agronomy, Ecological Science and Engineering, West Lafayette, IN 47907-2054, USA
| | - Linda S Lee
- Purdue University, Department of Agronomy, Ecological Science and Engineering, West Lafayette, IN 47907-2054, USA.
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Tomaszewski EJ, Ginder-Vogel M. Decreased Electron Transfer between Cr(VI) and AH2DS in the Presence of Goethite. JOURNAL OF ENVIRONMENTAL QUALITY 2018; 47:139-146. [PMID: 29415106 DOI: 10.2134/jeq2017.08.0316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
9,10-Anthraquinone-2,6-disulfonic acid (AQDS) is commonly used as a model species to examine the influence of quinones on different biogeochemical cycles. The reduced form of this quinone, AHDS, can donate electrons to the toxic metal species Cr(VI), leading to the precipitation of less soluble Cr(III) phases. Due to the environmental abundance of Fe(III) (oxyhydr)oxides, such as goethite (α-FeOOH), it is important to study the role of these mineral phases on the electron transfer reaction between AHDS and Cr(VI). In this study, this electron transfer reaction is examined in the presence and absence of goethite at three different ratios of AHDS/Cr(VI). Ultraviolet-visible spectroscopy is used to qualitatively assess the oxidation state of AQDS during reactions with goethite. Iron K-edge and Cr K-edge X-ray absorption spectroscopy are used to examine the role of goethite in electron transfer and identify Cr(III) phases that form. Goethite inhibits the extent of Cr(VI) reduction to Cr(III), most notably at the highest ratio of AHDS/Cr(VI) investigated. Production of semiquinone radical species may limit electron transfer and decrease the yields of Fe(II) and Cr(III), both in the presence and absence of goethite. Understanding abiotic electron transfer reactions that occur in systems with multiple redox active species is important to determine the contribution of abiotic redox reactions to Fe biogeochemical cycling in natural soils.
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Zarzycki P, Rosso KM. Stochastic Simulation of Isotopic Exchange Mechanisms for Fe(II)-Catalyzed Recrystallization of Goethite. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:7552-7559. [PMID: 28602094 DOI: 10.1021/acs.est.7b01491] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Understanding Fe(II)-catalyzed transformations of Fe(III)-(oxyhydr)oxides is critical for correctly interpreting stable isotopic distributions and for predicting the fate of metal ions in the environment. Recent Fe isotopic tracer experiments have shown that goethite undergoes rapid recrystallization without phase change when exposed to aqueous Fe(II). The proposed explanation is oxidation of sorbed Fe(II) and reductive Fe(II) release coupled 1:1 by electron conduction through crystallites. Given the availability of two tracer exchange data sets that explore pH and particle size effects (e.g., Handler et al. Environ. Sci. Technol. 2014 , 48 , 11302 - 11311 ; Joshi and Gorski Environ. Sci. Technol. 2016 , 50 , 7315 - 7324 ), we developed a stochastic simulation that exactly mimics these experiments, while imposing the 1:1 constraint. We find that all data can be represented by this model, and unifying mechanistic information emerges. At pH 7.5 a rapid initial exchange is followed by slower exchange, consistent with mixed surface- and diffusion-limited kinetics arising from prominent particle aggregation. At pH 5.0 where aggregation and net Fe(II) sorption are minimal, that exchange is quantitatively proportional to available particle surface area and the density of sorbed Fe(II) is more readily evident. Our analysis reveals a fundamental atom exchange rate of ∼10-5 Fe nm-2 s-1, commensurate with some of the reported reductive dissolution rates of goethite, suggesting Fe(II) release is the rate-limiting step in the conduction mechanism during recrystallization.
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Affiliation(s)
- Piotr Zarzycki
- Energy Geoscience Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
- Institute of Physical Chemistry, Polish Academy of Sciences , 01-224 Warsaw, Poland
| | - Kevin M Rosso
- Pacific Northwest National Laboratory, Richland, Washington 99354, United States
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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. ENVIRONMENTAL SCIENCE & TECHNOLOGY 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] [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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Wang Y, Xie X, Ma T, Pi K, Su C, Liu Y, Li J. Remediation of High Arsenic Aquifers by Learning from the Nature. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/j.proeps.2016.12.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Liao P, Yuan S, Wang D. Impact of Redox Reactions on Colloid Transport in Saturated Porous Media: An Example of Ferrihydrite Colloids Transport in the Presence of Sulfide. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:10968-10977. [PMID: 27654458 DOI: 10.1021/acs.est.6b02542] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Transport of colloids in the subsurface is an important environmental process with most research interests centered on the transport in chemically stable conditions. While colloids can be formed under dynamic redox conditions, the impact of redox reactions on their transport is largely overlooked. Taking the redox reactions between ferrihydrite colloids and sulfide as an example, we investigated how and to what extent the redox reactions modulated the transport of ferrihydrite colloids in anoxic sand columns over a range of environmentally relevant conditions. Our results reveal that the presence of sulfide (7.8-46.9 μM) significantly decreased the breakthrough of ferrihydrite colloids in the sand column. The estimated travel distance of ferrihydrite colloids in the absence of sulfide was nearly 7-fold larger than that in the presence of 46.9 μM sulfide. The reduced breakthrough was primarily attributed to the reductive dissolution of ferrihydrite colloids by sulfide in parallel with formation of elemental sulfur (S(0)) particles from sulfide oxidation. Reductive dissolution decreased the total mass of ferrihydrite colloids, while the negatively charged S(0) decreased the overall zeta potential of ferrihydrite colloids by attaching onto their surfaces and thus enhanced their retention in the sand. Our findings provide novel insights into the critical role of redox reactions on the transport of redox-sensitive colloids in saturated porous media.
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Affiliation(s)
- Peng Liao
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences , 388 Lumo Road, Wuhan 430074, P. R. China
| | - Songhu Yuan
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences , 388 Lumo Road, Wuhan 430074, P. R. China
| | - Dengjun Wang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences , 71 East Beijing Road, Nanjing 210008, P. R. China
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