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Xu J, Chen C, Hu X, Chen D, Bland G, Wielinski J, Kaegi R, Lin D, Lowry GV. Particle-Scale Understanding of Arsenic Interactions with Sulfidized Nanoscale Zerovalent Iron and Their Impacts on Dehalogenation Reactivity. Environ Sci Technol 2023; 57:21917-21926. [PMID: 38091483 PMCID: PMC10753793 DOI: 10.1021/acs.est.3c08635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 11/23/2023] [Accepted: 11/29/2023] [Indexed: 12/27/2023]
Abstract
Co-occurrence of organic contaminants and arsenic oxoanions occurs often at polluted groundwater sites, but the effect of arsenite on the reactivity of sulfidized nanoscale zerovalent iron (SNZVI) used to remediate groundwater has not been evaluated. Here, we study the interaction of arsenite [As(III)] with SNZVI at the individual-particle scale to better understand the impacts on the SNZVI properties and reactivity. Surface and intraparticle accumulation of As was observed on hydrophilic FeS-Fe0 and hydrophobic FeS2-Fe0 particles, respectively. X-ray absorption spectroscopy indicated the presence of realgar-like As-S and elemental As0 species at low and high As/Fe concentration ratios, respectively. Single-particle inductively coupled plasma time-of-flight mass spectrometry analysis identified As-containing particles both with and without Fe. The probability of finding As-containing particles without Fe increased with the S-induced hydrophobicity of SNZVI. The interactions of SNZVI materials with coexisting arsenite inhibited their reactivity with water (∼5.8-230.7-fold), trichloroethylene (∼3.6-67.5-fold), and florfenicol (∼1.1-5.9-fold). However, the overall selectivity toward trichloroethylene and florfenicol relative to water was improved (up to 9.0-fold) because the surface-associated As increased the SNZVI hydrophobicity. These results indicate that reactions of SNZVI with arsenite can remove As from groundwater and improve the properties of SNZVI for dehalogenation selectivity.
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Affiliation(s)
- Jiang Xu
- Zhejiang
Provincial Key Laboratory of Organic Pollution Process and Control,
Department of Environmental Science, Zhejiang
University, Hangzhou 310058, China
| | - Chaohuang Chen
- Zhejiang
Provincial Key Laboratory of Organic Pollution Process and Control,
Department of Environmental Science, Zhejiang
University, Hangzhou 310058, China
| | - Xiaohong Hu
- Zhejiang
Provincial Key Laboratory of Organic Pollution Process and Control,
Department of Environmental Science, Zhejiang
University, Hangzhou 310058, China
| | - Du Chen
- Zhejiang
Provincial Key Laboratory of Organic Pollution Process and Control,
Department of Environmental Science, Zhejiang
University, Hangzhou 310058, China
| | - Garret Bland
- Department
of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Jonas Wielinski
- Department
of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Ralf Kaegi
- Eawag,
Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, Dübendorf 8600, Switzerland
| | - Daohui Lin
- Zhejiang
Provincial Key Laboratory of Organic Pollution Process and Control,
Department of Environmental Science, Zhejiang
University, Hangzhou 310058, China
| | - Gregory V. Lowry
- Department
of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
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2
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Fox S, Stadnik K, Thakur AK, Farkash L, Ronen Z, Oren Y, Gilron J. Oxyanion Removal from Impaired Water by Donnan Dialysis Plug Flow Contactors. Membranes (Basel) 2023; 13:856. [PMID: 37999342 PMCID: PMC10673252 DOI: 10.3390/membranes13110856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 09/22/2023] [Accepted: 10/03/2023] [Indexed: 11/25/2023]
Abstract
In the last twenty-five years, extensive work has been done on ion exchange membrane bioreactors (IEMB) combining Donnan dialysis and anaerobic reduction to remove trace oxyanions (e.g., perchlorate, nitrate, chlorate, arsenate) from contaminated water sources. Most studies used Donnan dialysis contactors with high recirculation rates on the feed side, so under continuous operation, the effective concentration on the feed side of the membrane is the same as the exit concentration (CSTR mode). We have built, characterized, and modelled a plug flow Donnan dialysis contactor (PFR) that maximizes concentration on the feed side and operated it on feed solutions spiked with perchlorate and nitrate ion using ACS and PCA-100 anion exchange membranes. At identical feed inlet concentrations with the ACS membrane, membrane area loading rates are three-fold greater, and fluxes are more than double in the PFR contactor than in the CSTR contactor. A model based on the nonlinear adsorption of perchlorate in ACS membrane correctly predicted the trace ion concentration as a function of space-time in experiments with ACS. For PCA membrane, a linear flux dependence on feed concentration correctly described trace ion feed concentration as a function of space-time. Anion permeability for PCA-100 was high enough that the overall mass transfer was affected by the film boundary layer resistance. These results provide a basis for efficiently scaling up Donnan dialysis contactors and incorporating them in full-scale IEMB setups.
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Affiliation(s)
| | | | | | | | | | | | - Jack Gilron
- Zuckerberg Institute for Water Research, Blaustein Institutes of Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion 84990, Israel; (S.F.); (K.S.); (A.K.T.); (L.F.); (Z.R.); (Y.O.)
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3
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Liu X, Qin H, Xing S, Liu Y, Chu C, Yang D, Duan X, Mao S. Selective Removal of Organic Pollutants in Groundwater and Surface Water by Persulfate-Assisted Advanced Oxidation: The Role of Electron-Donating Capacity. Environ Sci Technol 2023; 57:13710-13720. [PMID: 37639499 DOI: 10.1021/acs.est.3c04870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
The efficiency of persulfate-assisted advanced oxidation processes (PS-AOPs) in degrading organic pollutants is affected by the electron-donating capability of organic substances present in the water source. In this study, we systematically investigate the electron-donating capacity (EDC) difference between groundwater and surface water and demonstrate the dependence of removal efficiency on the EDC of target water by PS-AOPs with carbon nanotubes (CNTs) as a catalyst. Laboratory analyses and field experiments reveal that the CNT/PS system exhibits higher performance in organic pollutant removal in groundwater with a high concentration of phenols, compared to surface water, which is rich in quinones. We attribute this disparity to the selective electron transfer pathway induced by potential difference between PS-CNT and organic substance-CNT intermediates, which preferentially degrade organic substances with stronger electron-donating capability. This study provides valuable insights into the inherent selective removal mechanism and application scenarios of electron transfer process-dominated PS-AOPs for water treatment based on the electron-donating capacity of organic pollutants.
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Affiliation(s)
- Xinru Liu
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Hehe Qin
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Siyang Xing
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Ying Liu
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Chengcheng Chu
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Dianhai Yang
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Xiaoguang Duan
- School of Chemical Engineering, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Shun Mao
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
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4
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You X, Liu S, Berns-Herrboldt EC, Dai C, Werth CJ. Kinetics of Hydroxyl Radical Production from Oxygenation of Reduced Iron Minerals and Their Reactivity with Trichloroethene: Effects of Iron Amounts, Iron Species, and Sulfate Reducing Bacteria. Environ Sci Technol 2023; 57:4892-4904. [PMID: 36921080 DOI: 10.1021/acs.est.3c00122] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Reactive oxygen species generated during the oxygenation of different ferrous species have been documented at groundwater field sites, but their effect on pollutant destruction remains an open question. To address this knowledge gap, a kinetic model was developed to probe mechanisms of •OH production and reactivity with trichloroethene (TCE) and competing species in the presence of reduced iron minerals (RIM) and oxygen in batch experiments. RIM slurries were formed by combining different amounts of Fe(II) and sulfide (with Fe(II):S ratios from 1:1 to 50:1) or Fe(II) and sulfate with sulfate reducing bacteria (SRB) added. Extents of TCE oxidation and •OH production were both greater with RIM prepared under more reducing conditions (more added Fe(II)) and then amended with O2. Kinetic rate constants from modeling indicate that •OH production from free Fe(II) dominates •OH production from solid Fe(II) and that TCE competes for •OH with Fe(II) and organic matter (OM). Competition with OM only occurs in experiments with SRB, which include cells and their exudates. Experimental results indicate that cells and/or exudates also provide electron equivalents to reform Fe(II) from oxidized RIM. Our work provides new insights into mechanisms and environmental significance of TCE oxidation by •OH produced from oxygenation of RIM. However, further work is necessary to confirm the relative importance of reaction pathways identified here and to probe potentially unaccounted for mechanisms that affect abiotic TCE oxidation in natural systems.
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Affiliation(s)
- Xueji You
- Department of Hydraulic Engineering, College of Civil Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
- Department of Civil, Architectural, and Environmental Engineering, The University of Texas at Austin, 301 E. Dean Keeton St., Stop C1786, Austin, Texas 78712, United States
| | - Shuguang Liu
- Department of Hydraulic Engineering, College of Civil Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
- The Yangtze River Water Environment Key Laboratory of the Ministry of Education, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Erin C Berns-Herrboldt
- Department of Civil, Architectural, and Environmental Engineering, The University of Texas at Austin, 301 E. Dean Keeton St., Stop C1786, Austin, Texas 78712, United States
| | - Chaomeng Dai
- Department of Hydraulic Engineering, College of Civil Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Charles J Werth
- Department of Civil, Architectural, and Environmental Engineering, The University of Texas at Austin, 301 E. Dean Keeton St., Stop C1786, Austin, Texas 78712, United States
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5
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Balda M, Mackenzie K, Woszidlo S, Uhlig H, Möllmer J, Kopinke FD, Schüürmann G, Georgi A. Bottom-Up Synthesis of De-Functionalized and Dispersible Carbon Spheres as Colloidal Adsorbent. Int J Mol Sci 2023; 24:ijms24043831. [PMID: 36835241 PMCID: PMC9964220 DOI: 10.3390/ijms24043831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/08/2023] [Accepted: 02/09/2023] [Indexed: 02/17/2023] Open
Abstract
Recent innovative adsorption technologies for water purification rely on micrometer-sized activated carbon (AC) for ultrafast adsorption or in situ remediation. In this study, the bottom-up synthesis of tailored activated carbon spheres (aCS) from sucrose as renewable feedstock is demonstrated. The synthesis is based on a hydrothermal carbonization step followed by a targeted thermal activation of the raw material. This preserves its excellent colloid properties, i.e., narrow particle size distribution around 1 µm, ideal spherical shape and excellent aqueous dispersibility. We investigated the ageing of the freshly synthesized, highly de-functionalized AC surface in air and aqueous media under conditions relevant to the practice. A slow but significant ageing due to hydrolysis and oxidation reactions was observed for all carbon samples, leading to an increase of the oxygen contents with storage time. In this study, a tailored aCS product was generated within a single pyrolysis step with 3 vol.-% H2O in N2 in order to obtain the desired pore diameters and surface properties. Adsorption characteristics, including sorption isotherms and kinetics, were investigated with monochlorobenzene (MCB) and perfluorooctanoic acid (PFOA) as adsorbates. The product showed high sorption affinities up to log (KD/[L/kg]) of 7.3 ± 0.1 for MCB and 6.2 ± 0.1 for PFOA, respectively.
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Affiliation(s)
- Maria Balda
- Department of Environmental Engineering, Helmholtz Centre for Environmental Research—UFZ, 04318 Leipzig, Germany
| | - Katrin Mackenzie
- Department of Environmental Engineering, Helmholtz Centre for Environmental Research—UFZ, 04318 Leipzig, Germany
| | - Silke Woszidlo
- Department of Environmental Engineering, Helmholtz Centre for Environmental Research—UFZ, 04318 Leipzig, Germany
| | - Hans Uhlig
- Institut für Nichtklassische Chemie e.V.—INC, 04318 Leipzig, Germany
| | - Jens Möllmer
- Institut für Nichtklassische Chemie e.V.—INC, 04318 Leipzig, Germany
| | - Frank-Dieter Kopinke
- Department of Environmental Engineering, Helmholtz Centre for Environmental Research—UFZ, 04318 Leipzig, Germany
| | - Gerrit Schüürmann
- Institute of Organic Chemistry, Technical University Bergakademie Freiberg, 09599 Freiberg, Germany
- Department of Ecological Chemistry, Helmholtz Centre for Environmental Research—UFZ, 04318 Leipzig, Germany
| | - Anett Georgi
- Department of Environmental Engineering, Helmholtz Centre for Environmental Research—UFZ, 04318 Leipzig, Germany
- Correspondence:
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6
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Masood Ul Hasan I, Javed H, Hussain MM, Shakoor MB, Bibi I, Shahid M, Xu N, Wei Q, Qiao J, Niazi NK. Biochar/nano-zerovalent zinc-based materials for arsenic removal from contaminated water. Int J Phytoremediation 2022; 25:1155-1164. [PMID: 36355569 DOI: 10.1080/15226514.2022.2140778] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
In this study, we explored the potential of a newly prepared nano-zero valent zinc (nZVZn), biochar (BC)/nZVZn and BC/hydroxyapatite-alginate (BC/HA-alginate) composites for the removal of inorganic As species from water. Relatively, higher percentage removal of As(III) and As(V) was obtained by nZVZn at pH 3.4 (96% and 94%, respectively) compared to BC/nZVZn (90% and 88%) and BC/HA-alginate (88% and 80%) at pH 7.2. Freundlich model provided the best fit (R2 = up to 0.98) for As(III) and As(V) sorption data of all the sorbents, notably for nZVZn. The pseudo-second order model well-described kinetics of As(III) and As(V) (R2 = 0.99) sorption on all the sorbents. The desorption experiments demonstrated that the As removal efficiency, up to the third sorption/desorption cycle, was in the order of nZVZn ∼ BC/HA-alginate (88%) > BC/nZVZn (84%). The Fourier transform infrared spectroscopy depicted that the -OH, -COOH, Zn-O and Zn-OH surface functional groups were responsible for the sorption of As(III) or As(V) on the sorbents investigated here. This study highlights that removal of As species from water by BC/nZVZn composite can be compared with nZVZn, suggesting that integrating BC with nZVZn could efficiently remove As from As-contaminated drinking water.
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Affiliation(s)
- Israr Masood Ul Hasan
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Environmental Science and Engineering, Donghua University, Shanghai, China
- Institute of Soil and Environmental Sciences, University of Agriculture Faisalabad, Faisalabad, Pakistan
| | - Haram Javed
- Institute of Soil and Environmental Sciences, University of Agriculture Faisalabad, Faisalabad, Pakistan
| | - Muhammad Mahroz Hussain
- Institute of Soil and Environmental Sciences, University of Agriculture Faisalabad, Faisalabad, Pakistan
| | | | - Irshad Bibi
- Institute of Soil and Environmental Sciences, University of Agriculture Faisalabad, Faisalabad, Pakistan
| | - Muhammad Shahid
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari, Pakistan
| | - Nengneng Xu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Environmental Science and Engineering, Donghua University, Shanghai, China
| | - Qunshan Wei
- Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China
| | - Jinli Qiao
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Environmental Science and Engineering, Donghua University, Shanghai, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, China
| | - Nabeel Khan Niazi
- Institute of Soil and Environmental Sciences, University of Agriculture Faisalabad, Faisalabad, Pakistan
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7
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Wang Z, Yang Z, Fagerlund F, Zhong H, Hu R, Niemi A, Illangasekare T, Chen YF. Pore-Scale Mechanisms of Solid Phase Emergence During DNAPL Remediation by Chemical Oxidation. Environ Sci Technol 2022; 56:11343-11353. [PMID: 35904865 DOI: 10.1021/acs.est.2c01311] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In situ chemical oxidation (ISCO) has proven successful in the remediation of aquifers contaminated with dense nonaqueous phase liquids (DNAPLs). However, the treatment efficiency can often be hampered by the formation of solids or gas, reducing the contact between remediation agents and residual DNAPLs. To further improve the efficiency of ISCO, fundamental knowledge is needed about the complex multiphase flow and reactive transport processes as new solid and fluid phases emerge at the microscale. Here, via microfluidic experiments, we study the pore-scale dynamics of trichloroethylene degradation by permanganate. We visualize how the remediation evolves under the influence of solid phase emergence and explore the roles of injection rate, oxidant concentration, and stabilization supplement. Combining image processing, pressure analysis, and stoichiometry calculations, we provide comprehensive descriptions of the oxidant concentration-dependent growth patterns of the solid phase and their impact on the remediation efficiency. We further corroborate the stabilization mechanism provided by phosphate supplement, which is effective in inhibiting solid phase generation and thus highly beneficial for the oxidation remediation. This work elucidates the pore-scale mechanisms during remediation of chlorinated solvents with a particular context in the solid phase production and the associated effects, which is of general significance to understanding various processes in natural and engineered systems involving solid phase emergence or aggregation phenomena, such as groundwater and soil remediation.
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Affiliation(s)
- Zejun Wang
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China
- Key Laboratory of Rock Mechanics in Hydraulic Structural Engineering of the Ministry of Education, Wuhan University, Wuhan 430072, China
| | - Zhibing Yang
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China
- Key Laboratory of Rock Mechanics in Hydraulic Structural Engineering of the Ministry of Education, Wuhan University, Wuhan 430072, China
| | - Fritjof Fagerlund
- Department of Earth Sciences, Uppsala University, Villavägen 16, SE-75236 Uppsala, Sweden
| | - Hua Zhong
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China
| | - Ran Hu
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China
- Key Laboratory of Rock Mechanics in Hydraulic Structural Engineering of the Ministry of Education, Wuhan University, Wuhan 430072, China
| | - Auli Niemi
- Department of Earth Sciences, Uppsala University, Villavägen 16, SE-75236 Uppsala, Sweden
| | - Tissa Illangasekare
- Department of Civil and Environmental Engineering, Center for Experimental Study of Subsurface Environmental Processes, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Yi-Feng Chen
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China
- Key Laboratory of Rock Mechanics in Hydraulic Structural Engineering of the Ministry of Education, Wuhan University, Wuhan 430072, China
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8
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Metzgen AD, Dahmke A, Ebert M. Temperature Effects on PCE Degradation on ZVI in Column Experiments with Deionized Water. Environ Sci Technol 2022; 56:10084-10094. [PMID: 35786861 DOI: 10.1021/acs.est.2c01235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The effects of rising groundwater temperatures on zerovalent iron (ZVI)-based remediation techniques will be critical in accelerating chlorinated hydrocarbon (CHC) degradation and side reactions. Therefore, tetrachloroethylene (PCE) degradation with three ZVIs widely used in permeable reactive barriers (Gotthart-Maier cast iron [GM], Peerless cast iron [PL], and ISPAT sponge iron [IS]) was evaluated at 10-70 °C in deionized water. From 10 to 70 °C, PCE degradation half-lives decreased from 25 ± 2 to 0.9 ± 0.1 h (PL), 24 ± 3 to 0.7 ± 0.1 h (GM), and 2.5 ± 0.01 to 0.3 ± 0.005 h (IS). Trichloroethylene (TCE) degradation half-lives at PL and GM decreased from 14.3 ± 3 to 0.2 ± 0.1 h (PL) and 7.6 ± 2 to 0.4 ± 0.1 h (GM). This acceleration of CHC degradation and the stronger shift toward reductive β-elimination reduced the concentration of potentially harmful metabolites with increasing temperatures. PCE and TCE degradation yields an activation energy of 28 (IS), 58 and 40 kJ mol-1 (GM), and 62 and 53 kJ mol-1 (PL). Hydrogen gas production by ZVI corrosion increased by 3 orders of magnitude from 10 to 70 °C, and an increased chance of gas clogging was observed at high temperatures.
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Affiliation(s)
- Adrian D Metzgen
- Department of Applied Geology, Aquatic Geochemistry and Hydrogeology, Institute of Geoscience, Kiel University, Ludewig-Meyn-Straße 10, 24118 Kiel, Germany
| | - Andreas Dahmke
- Department of Applied Geology, Aquatic Geochemistry and Hydrogeology, Institute of Geoscience, Kiel University, Ludewig-Meyn-Straße 10, 24118 Kiel, Germany
| | - Markus Ebert
- Department of Applied Geology, Aquatic Geochemistry and Hydrogeology, Institute of Geoscience, Kiel University, Ludewig-Meyn-Straße 10, 24118 Kiel, Germany
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9
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Mo Y, Xu J, Zhu L. Molecular Structure and Sulfur Content Affect Reductive Dechlorination of Chlorinated Ethenes by Sulfidized Nanoscale Zerovalent Iron. Environ Sci Technol 2022; 56:5808-5819. [PMID: 35442653 DOI: 10.1021/acs.est.2c00284] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Sulfidized nanoscale zerovalent iron (SNZVI) with desirable properties and reactivity has recently emerged as a promising groundwater remediation agent. However, little information is available on how the molecular structure of chlorinated ethenes (CEs) affects their dechlorination by SNZVI or whether the sulfur content of SNZVI can alter their dechlorination pathway and reactivity. Here, we show that the reactivity (up to 30-fold) and selectivity (up to 70-fold) improvements of SNZVI (compared to NZVI) toward CEs depended on the chlorine number, chlorine position, and sulfur content. Low CEs (i.e., vinyl chloride and cis-1,2-dichloroethene) and high CEs (perchloroethene) tended to be dechlorinated by SNZVI primarily via atomic H and direct electron transfer, respectively, while SNZVI could efficiently and selectively dechlorinate trichloroethene and trans-1,2-dichloroethene via both pathways. Increasing the sulfidation degree of SNZVI suppressed its ability to produce atomic H but promoted electron transfer and thus altered the relative contributions of atomic H and electron transfer to the CE dechlorination, resulting in different reactivities and selectivities. These were indicated by the correlations of CE dechlorination rates and improvements with CE molecular descriptors, H2 evolution rates, and electron transfer indicators of SNZVI. These mechanistic insights indicate the importance of determining the structure-specific properties and reactivity of both SNZVI materials and their target contaminants and can lead to a more rational design of SNZVI for in situ groundwater remediation of various CEs.
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Affiliation(s)
- Yalan Mo
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jiang Xu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China
| | - Lizhong Zhu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China
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10
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Kim Y, Son Y, Bae S, Kim TH, Hwang Y. Adsorption of Chromate Ions by Layered Double Hydroxide-Bentonite Nanocomposite for Groundwater Remediation. Nanomaterials (Basel) 2022; 12:nano12081384. [PMID: 35458092 PMCID: PMC9025721 DOI: 10.3390/nano12081384] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 04/11/2022] [Accepted: 04/14/2022] [Indexed: 02/05/2023]
Abstract
Herein, magnesium/aluminum-layered double hydroxide (MgAl-LDH) and bentonite (BT) nanocomposites (LDH–BT) were prepared by co-precipitation (CP), exfoliation–reassembly (ER), and simple solid-phase hybridization (SP). The prepared LDH–BT nanocomposites were preliminarily characterized by using powder X-ray diffractometry, scanning electron microscopy, and zeta-potentiometry. The chromate adsorption efficacies of the pristine materials (LDH and bentonite) and the as-prepared nanocomposites were investigated. Among the composites, the LDH–BT_SP was found to exhibit the highest chromate removal efficiency of 65.7%. The effect of varying the LDH amount in the LDH–BT composite was further investigated, and a positive relationship between the LDH ratio and chromate removal efficiency was identified. The chromate adsorption by the LDH–BT_SP was performed under various concentrations (isotherm) and contact times (kinetic). The results of the isotherm experiments were well fitted with the Langmuir and Freundlich isotherm model and demonstrate multilayer chromate adsorption by the heterogeneous LDH–BT_SP, with a homogenous distribution of LDH nanoparticles. The mobility of the as-prepared LDH–BT_SP was investigated on a silica sand-filled column to demonstrate that the mobility of the bentonite is dramatically decreased after hybridization with LDH. Furthermore, when the LDH–BT_SP was injected into a box container filled with silica sand to simulate subsurface soil conditions, the chromate removal efficacy was around 43% in 170 min. Thus, it was confirmed that the LDH–BT prepared by solid-phase hybridization is a practical clay-based nanocomposite for in situ soil and groundwater remediation.
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Affiliation(s)
- Yoogyeong Kim
- Department of Environmental Engineering, Seoul National University of Science and Technology, Seoul 01811, Korea; (Y.K.); (Y.S.)
| | - Yeongkyun Son
- Department of Environmental Engineering, Seoul National University of Science and Technology, Seoul 01811, Korea; (Y.K.); (Y.S.)
| | - Sungjun Bae
- Department of Civil and Environmental Engineering, Konkuk University, Seoul 05029, Korea;
| | - Tae-Hyun Kim
- Department of Environmental Engineering, Seoul National University of Science and Technology, Seoul 01811, Korea; (Y.K.); (Y.S.)
- Correspondence: (T.-H.K.); (Y.H.); Tel.: +82-2-970-6929 (T.-H.K.); +82-2-970-6626 (Y.H.); Fax: +82-2-971-5776 (T.-H.K. & Y.H.)
| | - Yuhoon Hwang
- Department of Environmental Engineering, Seoul National University of Science and Technology, Seoul 01811, Korea; (Y.K.); (Y.S.)
- Correspondence: (T.-H.K.); (Y.H.); Tel.: +82-2-970-6929 (T.-H.K.); +82-2-970-6626 (Y.H.); Fax: +82-2-971-5776 (T.-H.K. & Y.H.)
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11
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Meng F, Xu J, Dai H, Yu Y, Lin D. Even Incorporation of Nitrogen into Fe 0 Nanoparticles as Crystalline Fe 4N for Efficient and Selective Trichloroethylene Degradation. Environ Sci Technol 2022; 56:4489-4497. [PMID: 35316036 DOI: 10.1021/acs.est.1c08671] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Surface modification of microscale Fe powder with nitrogen has emerged recently to improve the reactivity of Fe0 for dechlorination. However, it is unclear how an even incorporation of a crystalline iron nitride phase into Fe0 nanoparticles affects their physicochemical properties and performance, or if Fe0 nanoparticles with a varied nitridation degree will act differently. Here, we synthesized nitridated Fe0 nanoparticles with an even distribution of N via a sol-gel and pyrolysis method. Nitridation expanded the Fe0 lattice and provided the Fe4N species, making the materials more hydrophobic and accelerating the electron transfer, compared to un-nitridated Fe0. These properties well explain their reactivity and selectivity toward trichloroethylene (TCE). The TCE degradation rate by nitridated Fe0 (up to 4.8 × 10-2 L m-2 h-1) was much higher (up to 27-fold) than that by un-nitridated Fe0, depending on the nitridation degree. The materials maintained a high electron efficiency (87-95%) due to the greatly suppressed water reactivity (109-127 times lower than un-nitridated Fe0). Acetylene was accumulated as the major product of TCE dechlorination via β-elimination. These findings suggest that the nitridation of Fe0 nanoparticles can change the materials' physicochemical properties, providing high reactivity and selectivity toward chlorinated contaminants for in situ groundwater remediation.
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Affiliation(s)
- Fanxu Meng
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
| | - Jiang Xu
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
- Zhejiang Ecological Civilization Academy, Anji 313300, China
| | - Huiwang Dai
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
| | - Yunlong Yu
- Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou 310058, China
| | - Daohui Lin
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
- Zhejiang Ecological Civilization Academy, Anji 313300, China
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12
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Miller E, Menashe O, Dosoretz CG. A tailored permeable reactive bio-barrier for in situ groundwater remediation: removal of 3-chlorophenol as a case study. Environ Technol 2022; 43:1200-1210. [PMID: 32912063 DOI: 10.1080/09593330.2020.1822922] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 09/07/2020] [Indexed: 06/11/2023]
Abstract
The present study explored bacterial aerobic biodegradation of reduced carbon-contaminants (RCC) in a pilot system mimicking remediation of a saturated aquifer in a permeable reactive biobarrier (PRBB). Bioaugmentation was performed with a pure culture of Pseudomonas putida macro-encapsulated in a cellulose-acetate porous envelope and integrated transversely to the flow trajectory of the fluid in the biobarrier and compared with controls without capsules. The macro-encapsulation technique applied allowed the incorporation of a built-in nutrient core for the slow release of macronutrients, i.e. N, P, instead of exogenous nutrients supply. 3-Chlorophenol (3CP) at a concentration range of 350-500 mg/L was chosen as an RCC model compound. The findings indicate efficient 3CP biodegradation during the PRBB operation with a similar degree of transformation (76 ± 2% and 72 ± 2%) and mineralization (55 ± 4% vs. 49 ± 3%) for exogenous and built-in nutrients supply, respectively. The extent of dechlorination in both cases (54 ± 10% vs. 40 ± 2%, respectively) followed mineralization rather than transformation, suggesting that Cl- release took place in late transformation stages. Negligible decontamination was observed in the control system without bioaugmentation. Concluding, tailored PRBB with macro-capsules incorporating a built-in nutrient core to support bacterial growth presents a significant environmental advantage controlling excess nutrients release required in bioremediation of oligotrophic systems.
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Affiliation(s)
- Efrat Miller
- Faculty of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Ofir Menashe
- Water Industry Engineering Department, Achi Racov Engineering School, Kinneret Academic College on the Sea of Galilee, D.N. Emek Ha'Yarden, Haifa, Israel
| | - Carlos G Dosoretz
- Faculty of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa, Israel
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13
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Cuong DV, Wu PC, Liou SYH, Hou CH. An integrated active biochar filter and capacitive deionization system for high-performance removal of arsenic from groundwater. J Hazard Mater 2022; 423:127084. [PMID: 34488095 DOI: 10.1016/j.jhazmat.2021.127084] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 08/20/2021] [Accepted: 08/27/2021] [Indexed: 06/13/2023]
Abstract
An integrated process of filtration and electrosorption was first applied to enable high-performance arsenic removal for groundwater remediation. An active manganese dioxide-rice husk biochar composite (active BC) filter was utilized for oxidization of As(III) to As(V) and initial removal of As(III, V). Subsequently, electrosorption by capacitive deionization (CDI) was applied as a posttreatment to improve arsenic removal. The active BC approach exhibited fast removal rates of 0.75 and 0.63 g mg-1 h-1 and high maximum removal capacities of 40.76 and 48.15 mg g-1 for As(III) and As(V), respectively. Importantly, column experiments demonstrated that the arsenic removal capacity in the active BC filter was 2.88 mg g-1, which was 72 times higher than that of BC. The results were due to the high efficiency (94%) of redox transformation of As(III) to As(V). The electrosorptive removal of arsenic was further controlled by changing the voltage in CDI. With a charging step of 1.2 V, the total arsenic concentration can be reduced to 0.001 mg L-1 with a low energy consumption of 0.0066 kW h m-3. Furthermore, the integrated system can remove As from real groundwater to achieve the World Health Organization guideline value for drinking water quality.
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Affiliation(s)
- Dinh Viet Cuong
- Faculty of Environmental Engineering, Hanoi University of Civil Engineering, 55 Giai Phong, Hai Ba Trung, Hanoi 100000, Vietnam
| | - Po-Chang Wu
- Graduate Institute of Environmental Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Rd., Taipei 10617, Taiwan
| | - Sofia Ya Hsuan Liou
- Department of Geosciences, National Taiwan University, No. 1, Section 4, Roosevelt Rd., Taipei 10617, Taiwan; Research Center for Future Earth, National Taiwan University, No. 1, Section 4, Roosevelt Rd., Taipei 10617, Taiwan
| | - Chia-Hung Hou
- Graduate Institute of Environmental Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Rd., Taipei 10617, Taiwan; Research Center for Future Earth, National Taiwan University, No. 1, Section 4, Roosevelt Rd., Taipei 10617, Taiwan.
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14
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Sun X, Lyu S. l-cysteine-modified Fe 3 O 4 nanoparticles as a novel heterogeneous catalyst for persulfate activation on BTEX removal. Water Environ Res 2021; 93:3023-3036. [PMID: 34676621 DOI: 10.1002/wer.1654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 10/08/2021] [Accepted: 10/13/2021] [Indexed: 06/13/2023]
Abstract
l-cysteine-modified Fe3 O4 nanoparticles (l-cys@nFe3 O4 ) were synthesized successfully and used as catalyst to activate persulfate (PS) for benzene, toluene, ethylbenzene, and xylenes (BTEX) degradation. The composite was fully characterized, and the l-cys@nFe3 O4 had more protrusions and l-cys was combined on the surface of nFe3 O4 . The removals of BTEX were 78.2%, 85.1%, 85.3%, 81.2%, respectively, in PS/l-cys@nFe3 O4 system, while only 52.7% 57.8%, 60.8%, and 56.3% of BTEX removals reached under the same condition for nFe3 O4 chelated with l-cys in 48 h. Four successive cycles of BTEX degradation were completed in PS/l-cys@nFe3 O4 system. The synergistic mechanisms of BTEX degradation in PS/l-cys@nFe3 O4 system were investigated by electron paramagnetic resonance (EPR), benzoic acid (BA) probe and X-ray photoelectron spectroscopy (XPS) tests. SFe bond in l-cys-Fe complexes promoted the electron transfer between nFe3 O4 core and the solution, iron and iron at the interface, thereby promoting the Fe3+ /Fe2+ cycle and the catalytic capacity of nFe3 O4 . The optimal pH of PS/l-cys@nFe3 O4 system was 3, while HCO3 - and Cl- exhibited negative influences on BTEX degradation. Only 14.2%, 15.5%, 15.9%, and 15.6% BTEX had been removed in the presence of 0.12-M PS and 8.0 g/L l-cys@nFe3 O4 under the actual groundwater condition. However, expanding the dosage of PS and l-cys@nFe3 O4 was an effective strategy to overcome the adverse effect. PRACTITIONER POINTS: L-cys@nFe3 O4 were synthesized successfully and used as catalyst to activate PS for BTEX degradation. Four successive cycles of BTEX degradation were completed in PS/L-cys@nFe3 O4 system. lS-Fe bond in L-cys@nFe3 O4 promoted the electron transfer between PS and nFe3 O4 core.
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Affiliation(s)
- Xuecheng Sun
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Shuguang Lyu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
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15
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Abstract
Increasing groundwater temperatures caused by global warming, subsurface infrastructure, or heat storage projects may interfere with groundwater remediation techniques using zero-valent iron (ZVI) technology by accelerating anaerobic corrosion. The corrosion behavior of three ZVIs widely used in permeable reactive barriers (PRBs), Peerless cast iron (PL), Gotthart-Maier cast iron (GM), and an ISPAT iron sponge (IS), was investigated at temperatures between 25 and 70 °C in half-open batch reactors by measuring the volume of hydrogen gas generated. Initially, the corrosion rates of all tested ZVIs increased with temperature; at temperatures ≤40 °C, a material-specific steady state is reached, and at temperatures >40 °C, passivation causes a decrease in long-term corrosion rates. The observed corrosion behavior was therefore assumed to be superimposed by accelerating and inhibiting effects, caused by surface precipitates where the fitting of measured corrosion rates by a modeling approach, using the corroded amount of Fe0 to account for passivating minerals, yields intrinsic activation energies (Ea, ZVI) of 81, 90, and 107 kJ mol-1 for IS, GM, and PL, respectively. An increase in H2 production might not be directly transferable to an increase in general ZVI reactivity; however, the results suggest that an increase in chlorinated hydrocarbon degradation rates can be expected for ZVI-PRBs in the immediate vicinity of low-temperature underground thermal energy storages (UTESs) or in the impact areas of high-temperature UTES with temperatures of ≤40 °C.
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Affiliation(s)
- Adrian D Metzgen
- Department of Applied Geology, Aquatic Geochemistry and Hydrogeology, Institute of Geoscience, Kiel University, Ludewig-Meyn-Straße 10, 24118 Kiel, Germany
| | - Andreas Dahmke
- Department of Applied Geology, Aquatic Geochemistry and Hydrogeology, Institute of Geoscience, Kiel University, Ludewig-Meyn-Straße 10, 24118 Kiel, Germany
| | - Markus Ebert
- Department of Applied Geology, Aquatic Geochemistry and Hydrogeology, Institute of Geoscience, Kiel University, Ludewig-Meyn-Straße 10, 24118 Kiel, Germany
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16
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Rossi MM, Silvani L, Amanat N, Petrangeli Papini M. Biochar from Pine Wood, Rice Husks and Iron-Eupatorium Shrubs for Remediation Applications: Surface Characterization and Experimental Tests for Trichloroethylene Removal. Materials (Basel) 2021; 14:ma14071776. [PMID: 33916830 PMCID: PMC8038453 DOI: 10.3390/ma14071776] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/24/2021] [Accepted: 03/28/2021] [Indexed: 12/01/2022]
Abstract
Nowadays porous materials from organic waste, i.e., Biochar (BC), are receiving increased attention for environmental applications. This study adds information on three BCs that have undergone a number of studies in recent years. A Biochar from pine wood, one from rice husk and one from Eupatorium shrubs enriched with Iron, labelled as PWBC, RHBC and EuFeBC respectively, are evaluated for Trichloroethylene (TCE) removal from aqueous solution. Physical-chemical description is performed by SEM-EDS and BET analysis. The decrease of TCE over time follows a pseudo-second order kinetics with increased removal by the PWBC. Freundlich and Langmuir models well fit equilibrium test data. The optimized values of the maximum adsorbed amount, qmax (mg g−1), follows this order 109.41 PWBC > 30.35 EuFeBC > 21.00 RHBC. Fixed-bed columns are also carried out. Best performance is again achieved by PWBC, which operates for a higher number of pore volume, followed by EuFeBC and RHBC. Continuous testing confirms batch studies and makes it possible to evaluate the workability of materials in configurations closer to reality. Results are promising for potential environmental application. In particular, the characterization of several classes of contaminants opens the doors to possible uses in mixed contamination cases.
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Affiliation(s)
- Marta M. Rossi
- Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy; (N.A.); (M.P.P.)
- Correspondence:
| | - Ludovica Silvani
- Aedes S.r.l. Research and Development, Aedes Chimica e Ambiente, Via Cancelliera 12, 00041 Albano Laziale, Italy;
| | - Neda Amanat
- Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy; (N.A.); (M.P.P.)
| | - Marco Petrangeli Papini
- Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy; (N.A.); (M.P.P.)
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17
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Huang J, Danish M, Jiang X, Tang P, Sui Q, Qiu Z, Lyu S. Trichloroethylene degradation performance in aqueous solution by Fe(II) activated sodium percarbonate in the presence of surfactant sodium dodecyl sulfate. Water Environ Res 2020; 92:1142-1151. [PMID: 32060999 DOI: 10.1002/wer.1309] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 02/03/2020] [Accepted: 02/10/2020] [Indexed: 06/10/2023]
Abstract
The performance of trichloroethylene (TCE) degradation by sodium percarbonate (SPC) activated with Fe(II) in the presence of 3.0 g/L sodium dodecyl sulfate (SDS) as well as the role of SDS in the SPC/Fe(II) system was investigated since SDS is a common surfactant used in groundwater remediation for improving TCE dissolution to the aqueous phase. The results showed that though the introduction of SDS could inhibit the TCE degradation, the inhibiting effect was less with the increasing SDS dose. In the presence of SDS, TCE could be completely removed with the SPC/Fe(II)/TCE molar ratio of 40/80/1. Experiments with free radical probe compounds and radical scavengers elucidated that TCE was mainly oxidized by both HO· and O 2 - · . A weakly acidic environment was more favorable to TCE degradation. Nevertheless, HCO 3 - at a high concentration had a strongly inhibitive effect on the TCE degradation but the influence of Cl- was negligible. Finally, the excellent TCE degradation achieved in actual groundwater demonstrated that Fe(II) activated SPC technique was applicable in the remediation of TCE contaminated groundwater in the presence of SDS. PRACTITIONER POINTS: The effects of SDS were evaluated SPC/Fe(II)/SDS system applied to remediate TCE The mechanism of HO· and O 2 - · generation had been investigated Cl- and HCO 3 - affected TCE degradation at different levels The performance of TCE removal in actual groundwater had been studied.
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Affiliation(s)
- Jingyao Huang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Muhammad Danish
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
- Chemical Engineering Department, University of Engineering and Technology (UET), Lahore, Pakistan
| | - Xihao Jiang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Ping Tang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Qian Sui
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Zhaofu Qiu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Shuguang Lyu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
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18
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Cordova EA, Garayburu-Caruso V, Pearce CI, Cantrell KJ, Morad JW, Gillispie EC, Riley BJ, Colon FC, Levitskaia TG, Saslow SA, Qafoku O, Resch CT, Rigali MJ, Szecsody JE, Heald SM, Balasubramanian M, Meyers P, Freedman VL. Hybrid Sorbents for 129I Capture from Contaminated Groundwater. ACS Appl Mater Interfaces 2020; 12:26113-26126. [PMID: 32421326 DOI: 10.1021/acsami.0c01527] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Radioiodine (129I) poses a risk to the environment due to its long half-life, toxicity, and mobility. It is found at the U.S. Department of Energy Hanford Site due to legacy releases of nuclear wastes to the subsurface where 129I is predominantly present as iodate (IO3-). To date, a cost-effective and scalable cleanup technology for 129I has not been identified, with hydraulic containment implemented as the remedial approach. Here, novel high-performing sorbents for 129I remediation with the capacity to reduce 129I concentrations to or below the US Environmental Protection Agency (EPA) drinking water standard and procedures to deploy them in an ex-situ pump and treat (P&T) system are introduced. This includes implementation of hybridized polyacrylonitrile (PAN) beads for ex-situ remediation of IO3--contaminated groundwater for the first time. Iron (Fe) oxyhydroxide and bismuth (Bi) oxyhydroxide sorbents were deployed on silica substrates or encapsulated in porous PAN beads. In addition, Fe-, cerium (Ce)-, and Bi-oxyhydroxides were encapsulated with anion-exchange resins. The PAN-bismuth oxyhydroxide and PAN-ferrihydrite composites along with Fe- and Ce-based hybrid anion-exchange resins performed well in batch sorption experiments with distribution coefficients for IO3- of >1000 mL/g and rapid removal kinetics. Of the tested materials, the Ce-based hybrid anion-exchange resin was the most efficient for removal of IO3- from Hanford groundwater in a column system, with 50% breakthrough occurring at 324 pore volumes. The functional amine groups on the parent resin and amount of active sorbent in the resin can be customized to improve the iodine loading capacity. These results highlight the potential for IO3- remediation by hybrid sorbents and represent a benchmark for the implementation of commercially available materials to meet EPA standards for cleanup of 129I in a large-scale P&T system.
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Affiliation(s)
- Elsa A Cordova
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Vanessa Garayburu-Caruso
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Carolyn I Pearce
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Kirk J Cantrell
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Joseph W Morad
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Elizabeth C Gillispie
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Brian J Riley
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Ferdinan Cintron Colon
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Tatiana G Levitskaia
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Sarah A Saslow
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Odeta Qafoku
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Charles T Resch
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Mark J Rigali
- Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
| | - Jim E Szecsody
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Steve M Heald
- Advanced Photon Source, Argonne National Laboratory, Argonne Illinois 60439, United States
| | | | - Peter Meyers
- Resin Tech, West Berlin, New Jersey 08091, United States
| | - Vicky L Freedman
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
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19
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Pak T, Luz LFL Jr, Tosco T, Costa GSR, Rosa PRR, Archilha NL. Pore-scale investigation of the use of reactive nanoparticles for in situ remediation of contaminated groundwater source. Proc Natl Acad Sci U S A 2020; 117:13366-73. [PMID: 32487728 DOI: 10.1073/pnas.1918683117] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Chlorinated solvents are among the most recalcitrant aquifer contaminants, which can cause serious health problems such as kidney and liver damage, and some are considered carcinogenic. They are a global problem due to their wide industrial use since the beginning of the 20th century (e.g., in metal-processing plants). Conventionally, pump and treat technology (ex situ method) has been used to treat such contaminated groundwater resources. Recently, in situ techniques have been applied to lower the remediation costs (e.g., energy/water consumption) while also limiting the disruption. Nanoremediation is a new in situ technology that has shown promising results at laboratory, pilot, and field scales. This study uses 4D (time-resolved 3D) imaging to capture the dynamics of nanoremediation at the pore scale. Nanoscale zero-valent iron (nZVI) particles have excellent capacity for in situ remediation of groundwater resources contaminated by a range of organic and inorganic contaminants. Chlorinated solvents are by far the most treated compounds. Studies at column, pilot, and field scales have reported successful decrease in contaminant concentration upon injection of nZVI suspensions in the contaminated zones. However, the field application is far from optimized, particularly for treatments at—or close to—the source, in the presence of residual nonaqueous liquid (NAPL). The knowledge gaps surrounding the processes that occur within the pores of the sediments hosting those contaminants at microscale limit our ability to design nanoremediation processes that are optimized at larger scales. This contribution provides a pore-scale picture of the nanoremediation process. Our results reveal how the distribution of the trapped contaminant evolves as a result of contaminant degradation and generation of gaseous products. We have used state-of-the-art four-dimensional (4D) imaging (time-resolved three-dimensional [3D]) experiments to understand the details of this degradation reaction at the micrometer scale. This contribution shows that the gas released (from the reduction reaction) remobilizes the trapped contaminant by overcoming the capillary forces. Our results show that the secondary sources of NAPL contaminations can be effectively treated by nZVI, not only by in situ degradation, but also through pore-scale remobilization (induced by the evolved gas phase). The produced gas reduces the water relative permeability to less than 1% and, therefore, significantly limits the extent of plume migration in the short term.
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20
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Sun X, Sun Y, Lyu S, Qiu Z, Sui Q. The performance of nCaO 2 for BTEX removal: Hydroxyl radical generation pattern and the influences of co-existing environmental pollutants. Water Environ Res 2020; 92:622-630. [PMID: 31608527 DOI: 10.1002/wer.1257] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 09/29/2019] [Accepted: 10/09/2019] [Indexed: 06/10/2023]
Abstract
In this study, nano-CaO2 (nCaO2 ) was successfully synthesized and constituted the nCaO2 /Fe(II) system applying to remediate BTEX, which are typical mixed pollutants in contaminated groundwater. The particle size of the synthesized nCaO2 was 108.91 nm, and it displayed better BTEX remediation performance than that of commercial CaO2 . The innovative generation pattern of hydroxyl radicals ( HO · ) in the nCaO2 /Fe(II) system has been investigated using benzoic acid as the HO · probe, and the proper molar ratio of nCaO2 /Fe(II) was optimized as 1/1. Over 90% of BTEX was removed in 180 min with the nCaO2 /Fe(II)/BTEX molar ratio of 40/40/1. Further experiments evaluated the influence of co-existence of mixed pollutants chlorinated hydrocarbon compounds (CHCs) or surfactant constituents on BTEX remediation performance. The experimental results suggested that CHCs have limited influence on BTEX removal rate and surfactants have negative effects on BTEX remediation performance in the experimental conditions. In conclusion, the findings in this study could give some inspirations to apply the nCaO2 /Fe(II) process in remediating co-existing pollutants in contaminated groundwater. PRACTITIONER POINTS: nCaO2 /Fe(II) system applied to remediate mixed contaminants. HO · generation pattern of the nCaO2 /Fe(II) system has been investigated. The influence of chloride hydrocarbon compounds have been studied. The effects of surfactants were evaluated.
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Affiliation(s)
- Xuecheng Sun
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Yong Sun
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Shuguang Lyu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Zhaofu Qiu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Qian Sui
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
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Xu J, Avellan A, Li H, Liu X, Noël V, Lou Z, Wang Y, Kaegi R, Henkelman G, Lowry GV. Sulfur Loading and Speciation Control the Hydrophobicity, Electron Transfer, Reactivity, and Selectivity of Sulfidized Nanoscale Zerovalent Iron. Adv Mater 2020; 32:e1906910. [PMID: 32162726 DOI: 10.1002/adma.201906910] [Citation(s) in RCA: 116] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 01/27/2020] [Indexed: 06/10/2023]
Abstract
Sulfidized nanoscale zerovalent iron (SNZVI) is a promising material for groundwater remediation. However, the relationships between sulfur content and speciation and the properties of SNZVI materials are unknown, preventing rational design. Here, the effects of sulfur on the crystalline structure, hydrophobicity, sulfur speciation, corrosion potential, and electron transfer resistance are determined. Sulfur incorporation extended the nano-Fe0 BCC lattice parameter, reduced the Fe local vacancies, and lowered the resistance to electron transfer. Impacts of the main sulfur species (FeS and FeS2 ) on hydrophobicity (water contact angles) are consistent with density functional theory calculations for these FeSx phases. These properties well explain the reactivity and selectivity of SNZVI during the reductive dechlorination of trichloroethylene (TCE), a hydrophobic groundwater contaminant. Controlling the amount and speciation of sulfur in the SNZVI made it highly reactive (up to 0.41 L m-2 d-1 ) and selective for TCE degradation over water (up to 240 moles TCE per mole H2 O), with an electron efficiency of up to 70%, and these values are 54-fold, 98-fold, and 160-fold higher than for NZVI, respectively. These findings can guide the rational design of robust SNZVI with properties tailored for specific application scenarios.
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Affiliation(s)
- Jiang Xu
- Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
- Center for Environmental Implications of NanoTechnology, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Astrid Avellan
- Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
- Center for Environmental Implications of NanoTechnology, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Hao Li
- Department of Chemistry and the Oden Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, Texas, 78712, USA
| | - Xitong Liu
- Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Vincent Noël
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA
| | - Zimo Lou
- Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Yan Wang
- Department of Civil and Environmental Engineering, University of Pittsburgh, Pittsburgh, PA, 15261, USA
| | - Rälf Kaegi
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, 8600, Dübendorf, Switzerland
| | - Graeme Henkelman
- Department of Chemistry and the Oden Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, Texas, 78712, USA
| | - Gregory V Lowry
- Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
- Center for Environmental Implications of NanoTechnology, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
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Chen Q, Fan G, Na W, Liu J, Cui J, Li H. Past, Present, and Future of Groundwater Remediation Research: A Scientometric Analysis. Int J Environ Res Public Health 2019; 16:E3975. [PMID: 31635235 DOI: 10.3390/ijerph16203975] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 10/13/2019] [Accepted: 10/14/2019] [Indexed: 11/17/2022]
Abstract
In this study, we characterize the body of knowledge of groundwater remediation from 1950 to 2018 by employing scientometric techniques and CiteSpace software, based on the Science Citation Index Expanded (SCI-E) databases. The results indicate that the United States and China contributed 56.4% of the total publications and were the major powers in groundwater remediation research. In addition, the United States, Canada, and China have considerable capabilities and expertise in groundwater remediation research. Groundwater remediation research is a multidisciplinary field, covering water resources, environmental sciences and ecology, environmental sciences, and engineering, among other fields. Journals such as Environmental Science and Technology, Journal of Contaminant Hydrology, and Water Research were the major sources of cited works. The research fronts of groundwater remediation were transitioning from the pump-and-treat method to permeable reactive barriers and nanoscale zero‑valent iron particles. The combination of new persulfate ion‑activation technology and nanotechnology is receiving much attention. Based on the visualized networks, the intelligence base was verified using a variety of metrics. Through landscape portrayal and developmental trajectory identification of groundwater remediation research, this study provides insight into the characteristics of, and global trends in, groundwater remediation, which will facilitate the identification of future research directions.
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Saha AK, Sinha A, Pasupuleti S. Modification, characterization and investigations of key factors controlling the transport of modified nano zero-valent iron (nZVI) in porous media. Environ Technol 2019; 40:1543-1556. [PMID: 29319455 DOI: 10.1080/09593330.2018.1426637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 01/07/2018] [Indexed: 06/07/2023]
Abstract
Enhancement of nano zero-valent iron (nZVI) stability and transport in the subsurface environment is important for in situ degradation of contaminants. Various biodegradable dispersants (poly (acrylic acid) (PAA), Tween 20 and Reetha Extracts) have been tested to evaluate their effectiveness in this regard. Application of dispersants during the synthesis of nZVI have positively affected the reduction in particle size. The transport capacity in terms of fraction elution at different pore water velocities and collector grain size (filter media) was analyzed using correlation equation for the filtration model by Rajagopalan and Tien (RT model). At a surfactant concentration of 5% for PAA, Tween 20 and Reetha (Sapindus trifoliata) extracts, the lowest particle size and the highest zeta potential achieved are 8.67 nm and -55.29 mV, 75.24 nm and -62.68 mV, 61.6 nm and -37.82 mV, respectively. The trend of colloidal stability by The Derjaguin-Landau-Verwey-Overbeek (DLVO) Theory model for PAA and Reetha applied concentration was 3% > 4% > 5% > 2% > 1% > 0%. For Tween 20, modified nZVI particle shows a higher repulsive force with increasing Tween 20 concentration. Results indicated that some mechanisms such as aggregation, ripening and surface modification with different carrier pore water velocities had a considerable impact on nZVI retention in porous media. The results indicate that natural surfactant like Reetha extracts exhibits an alternative potential capacity for nZVI modification in comparison with synthetic surfactants (PAA and Tween 20).
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Affiliation(s)
- Amal Krishna Saha
- a Department of Environmental Science and Engineering , Indian Institute of Technology (Indian School of Mines) , Dhanbad , India
| | - Alok Sinha
- a Department of Environmental Science and Engineering , Indian Institute of Technology (Indian School of Mines) , Dhanbad , India
| | - Srinivas Pasupuleti
- b Department of Civil Engineering , Indian Institute of Technology (Indian School of Mines) , Dhanbad , India
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Tang P, Jiang W, Lyu S, Brusseau ML, Xue Y, Qiu Z, Sui Q. Mechanism of carbon tetrachloride reduction in ferrous ion activated calcium peroxide system in the presence of methanol. Chem Eng J 2019; 362:243-250. [PMID: 31588180 PMCID: PMC6777862 DOI: 10.1016/j.cej.2019.01.034] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This study investigated the reductive initiation for the depletion of highly oxidized/perhalogenated pollutants, specifically the degradation of carbon tetrachloride (CT) was induced by adding methanol (MeOH) into a ferrous ion (Fe(II)) activated calcium peroxide (CaO2) system. The results indicated that CT could be completely degraded within 20 min at CaO2/Fe(II)/MeOH/CT molar ratio of 30/40/10/1 in this system. Scavenging tests suggested that both superoxide radical anion (O2 •-) and carbon dioxide radical anion (CO2 •-) were predominant reactive species responsible for CT destruction. Hydroxymethyl radicals (•CH2OH), an intermediate in the transformation of MeOH, could also initiate CT degradation by reducing C-Cl bond. GC/MS analysis identified CHCl3, C2Cl4, and C2Cl6 as the intermediates accompanied by CT destruction, and a reduction mechanism for CT degradation was proposed accordingly. In addition, the impact of solution matrix and initial solution pH were evaluated, and the results showed that Cl-, NO3 -, and HCO3 - had adverse effects on CT degradation. Moreover, the alkaline condition was unfavorable to CT depletion. In conclusion, the results obtained in the actual groundwater tests encouragingly demonstrated that the CaO2/Fe(II)/MeOH process is a highly promising technique for the remediation of CT-contaminated groundwater.
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Affiliation(s)
- Ping Tang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Wenchao Jiang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Shuguang Lyu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Mark L. Brusseau
- Soil, Water and Environmental Science Department, School of Earth and Environmental Sciences, The University of Arizona, 429 Shantz Building, Tucson, AZ 85721, United States
| | - Yunfei Xue
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Zhaofu Qiu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Qian Sui
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
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Tabassum RA, Shahid M, Niazi NK, Dumat C, Zhang Y, Imran M, Bakhat HF, Hussain I, Khalid S. Arsenic removal from aqueous solutions and groundwater using agricultural biowastes-derived biosorbents and biochar: a column-scale investigation. Int J Phytoremediation 2019; 21:509-518. [PMID: 30924354 DOI: 10.1080/15226514.2018.1501340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
In this study, column-scale laboratory experiments were performed to evaluate the arsenic (As) removal efficiency of different agricultural biowastes-derived biosorbents (orange peel, banana peel, rice husk) and biochar, using As-containing solutions and As-contaminated groundwater. All the biosorbents and biochar efficiently removed (50-100%) As from groundwater (drinking well water). Arsenic removal potential of biosorbents varied with their type, As concentration, contact time, and As solution type. After 1 h, the As removal efficiency of all the biosorbents was 100%, 100% and 90% for 5, 10, and 50 µg/L As-contaminated groundwater samples, respectively; and it was 50%, 90%, and 90% for 10, 50, and 100 µg/L As solutions, respectively. After 2 h, all the biosorbents and biochar removed 100% As from aqueous solutions except for 100 µg/L As solution. This showed that the biosorbents and biochar could be used to reduce As contents below the WHO safe limit of As in drinking water (10 µg/L). Fourier transform infrared (FTIR) spectroscopy indicated possible role of various surface functional moieties on biosorbents/biochar surface to remove As from solution and groundwater. This pilot-scale column study highlights that the biosorbents and biochar can be effectively used in remediation of As-contaminated groundwater, although the soluble salts in groundwater increased after treatment with biochar.
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Affiliation(s)
- Riaz Ahmad Tabassum
- a Department of Environmental Sciences , COMSATS University Islamabad , Vehari Campus, Vehari , Pakistan
| | - Muhammad Shahid
- a Department of Environmental Sciences , COMSATS University Islamabad , Vehari Campus, Vehari , Pakistan
| | - Nabeel Khan Niazi
- b Institute of Soil and Environmental Sciences, University of Agriculture Faisalabad , Faisalabad , Pakistan
- c MARUM and Department of Geosciences , University of Bremen , Bremen , Germany
- d Southern Cross GeoScience, Southern Cross University , Lismore , NSW , Australia
| | - Camille Dumat
- e Centre d'Etude et de Recherche Travail Organisation Pouvoir (CERTOP), Université J. Jaurès - Toulouse II , Toulouse Cedex 9 , France
| | - Yongqing Zhang
- f School of Environmental Science and Engineering , South China University of Technology , Guangzhou , P.R. China
- g The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education , Guangzhou , P.R. China
- h Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology , Guangzhou , P.R. China
| | - Muhammad Imran
- a Department of Environmental Sciences , COMSATS University Islamabad , Vehari Campus, Vehari , Pakistan
| | - Hafiz Faiq Bakhat
- a Department of Environmental Sciences , COMSATS University Islamabad , Vehari Campus, Vehari , Pakistan
| | - Imtyaz Hussain
- f School of Environmental Science and Engineering , South China University of Technology , Guangzhou , P.R. China
| | - Sana Khalid
- a Department of Environmental Sciences , COMSATS University Islamabad , Vehari Campus, Vehari , Pakistan
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26
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Zhang W, Yin L, Zhou NQ. [Development and Evaluation of a Sustainable Long-release Carbon Material Applied for In-Situ Remediation of Groundwater Nitrogen Pollution]. Huan Jing Ke Xue 2018; 39:4150-4160. [PMID: 30188056 DOI: 10.13227/j.hjkx.201711091] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Due to slow flow rates and inter-substance reactions in groundwater, remediation requires the addition of materials with sustained release properties. This research uses agricultural waste and zero-valent iron (Fe0), coupling biology and chemistry, to research and develop a sustainable long-release carbon material with a synergistic physico-habitat, and to evaluate its performance, also taking into account the occurrence of nitrogen in groundwater. The material developed has a double-layer structure with an inner core and an outer shell. The core, consisting of agricultural waste, Fe0, and other raw materials, constitutes the repair layer. Agricultural waste provides a carbon source for microorganisms, and Fe0 can quickly remove nitrate via chemical reactions and reduce DO to develop an anaerobic environment in water. The shell provides a solute permeation layer and consists of primary minerals and other components. This can slow the release of TOC from the core and adsorb secondary contaminants. Physical properties testing showed that the materials core was uniformly cross-linked, and its shell exhibited a clear uniform pore structure (SEM). Favorable mechanical compression was recorded for particle strengths of up to 80-105 N. With a density of 1.1 g·cm-3, the material did not float in water. Experiments showed that the material had excellent sustained release. The amount[Max:21-25 mg·(g·L)-1] and rate[Max:0.185 mg·(g·L·d)-1] of TOC release exhibited a steady state trend, but fluctuated greatly in the case of agricultural wastes[(Max amount:53-75 mg·(g·L)-1, Max rate:0.455 mg·(g·L·d)-1]. In terms of further functional gene abundance, materials leachate was found to be conducive to denitrifying bacteria. In early denitrification and oxygen trapping experiments, the Fe0 chemical reaction was dominant for reduction of nitrogen and DO, facilitating denitrification. However, biological denitrification gradually dominated. Differences in denitrification rates between iron-free and iron-containing materials were smaller, as was the correlation between denitrification rate and iron content. These results indicate the formation of physico-habitat synergistic denitrification in the materials system.
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Affiliation(s)
- Wen Zhang
- College of Civil Engineering, Tongji University, Shanghai 200092, China.,School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China
| | - Lin Yin
- School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China
| | - Nian-Qing Zhou
- College of Civil Engineering, Tongji University, Shanghai 200092, China
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Danish M, Gu X, Lu S, Brusseau ML, Ahmad A, Naqvi M, Farooq U, Zaman WQ, Fu X, Miao Z. An efficient catalytic degradation of trichloroethene in a percarbonate system catalyzed by ultra-fine heterogeneous zeolite supported zero valent iron-nickel bimetallic composite. Appl Catal A Gen 2017; 531:177-186. [PMID: 29104369 PMCID: PMC5665389 DOI: 10.1016/j.apcata.2016.11.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Zeolite supported nano iron-nickel bimetallic composite (Z-nZVI-Ni) was prepared using a liquid-phase reduction process. The corresponding surface morphologies and physico-chemical properties of the Z-nZVI-Ni composite were determined using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Energy dispersive X-ray spectra (EDS), Brunauer Emmett Teller (BET) adsorption, wide angle X-ray diffractometry (WA-XRD), and Fourier transform infrared spectroscopy (FTIR). The results indicated high dispersion of iron and nickel nano particles on the zeolite sheet with an enhanced surface area. Complete destruction of trichloroethene (TCE) and efficient removal of total organic carbon (TOC) were observed by using Z-nZVI-Ni as a heterogeneous catalyst for a Fenton-like oxidation process employing sodium percarbonate (SPC) as an oxidant. The electron spin resonance (ESR) of Z-nZVI-Ni verified the generation and intensity of hydroxyl radicals (OH•). The quantification of OH• elucidated by using p-chlorobenzoic acid, a probe indicator, confirmed the higher intensity of OH•. The transformation products were identified using GC-MS. The slow iron and nickel leaching offered higher stability and better catalytic activity of Z-nZVI-Ni, demonstrating its prospective long term applications in groundwater for TCE degradation.
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Affiliation(s)
- Muhammad Danish
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Xiaogang Gu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Shuguang Lu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Mark L. Brusseau
- Soil, Water and Environmental Science Department, School of Earth and Environmental Sciences, The University of Arizona, 429 Shantz Bldg., Tucson, AZ 85721, United States
| | - Ayyaz Ahmad
- Department of Chemical Engineering, Muhammad Nawaz Sharif University of Engineering and Technology, Multan, Pakistan
| | - Muhammad Naqvi
- Department of Energy, Building and Environment, Mälardalen University, Västerås 72123, Sweden
| | - Usman Farooq
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Waqas Qamar Zaman
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Xiaori Fu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Zhouwei Miao
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
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28
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Jha KC, Liu Z, Vijwani H, Nadagouda M, Mukhopadhyay SM, Tsige M. Carbon Nanotube Based Groundwater Remediation: The Case of Trichloroethylene. Molecules 2016; 21:E953. [PMID: 27455218 PMCID: PMC6273658 DOI: 10.3390/molecules21070953] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 07/06/2016] [Accepted: 07/08/2016] [Indexed: 12/07/2022] Open
Abstract
Adsorption of chlorinated organic contaminants (COCs) on carbon nanotubes (CNTs) has been gaining ground as a remedial platform for groundwater treatment. Applications depend on our mechanistic understanding of COC adsorption on CNTs. This paper lays out the nature of competing interactions at play in hybrid, membrane, and pure CNT based systems and presents results with the perspective of existing gaps in design strategies. First, current remediation approaches to trichloroethylene (TCE), the most ubiquitous of the COCs, is presented along with examination of forces contributing to adsorption of analogous contaminants at the molecular level. Second, we present results on TCE adsorption and remediation on pure and hybrid CNT systems with a stress on the specific nature of substrate and molecular architecture that would contribute to competitive adsorption. The delineation of intermolecular interactions that contribute to efficient remediation is needed for custom, scalable field design of purification systems for a wide range of contaminants.
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Affiliation(s)
- Kshitij C Jha
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA.
| | - Zhuonan Liu
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA.
| | - Hema Vijwani
- Center for Nanoscale Multifunctional Materials, Wright State University, Dayton, OH 45435, USA.
| | - Mallikarjuna Nadagouda
- Center for Nanoscale Multifunctional Materials, Wright State University, Dayton, OH 45435, USA.
| | - Sharmila M Mukhopadhyay
- Center for Nanoscale Multifunctional Materials, Wright State University, Dayton, OH 45435, USA.
| | - Mesfin Tsige
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA.
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Ruan X, Gu X, Lu S, Qiu Z, Sui Q. Trichloroethylene degradation by persulphate with magnetite as a heterogeneous activator in aqueous solution. Environ Technol 2015; 36:1389-1397. [PMID: 25496173 DOI: 10.1080/09593330.2014.991353] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Iron oxide-magnetite (Fe3O4) as a heterogeneous activator to activate persulphate anions (S2O8(2-)) for trichloroethylene (TCE) degradation was investigated in this study. The experimental results showed that TCE could be completely oxidized within 5 h by using 5 g L(-1) magnetite and 63 mM S2O8(2-), indicating the effectiveness of the process for TCE removal. Various factors of the process, including. (S2O8(2-) and magnetite dosages, and initial solution pH, were evaluated, and TCE degradation fitted well to the pseudo-first-order kinetic model. The calculated kinetic rate constant was increased with increasing S2O8(2-) and magnetite dosages, but it was independent of solution pH. In addition, the changes of magnetite morphology examined by scanning electron microscopy and X-ray powder diffraction, respectively, confirmed the slight corrosion with α-Fe2O3 coated on the magnetite surface. The probe compounds tests clearly identified the generation of the reactive oxygen species in the system. While the free radical quenching studies further demonstrated that •SO4- and •OH were the major radicals responsible for TCE degradation, whereas •O2- contributed less in the system, and therefore the roles of reactive oxygen species on TCE degradation mechanisms were proposed accordingly. To our best knowledge, this is the first time the performance and mechanism of magnetite-activated persulphate oxidation for TCE degradation are reported. The findings of this study provided a new insight into the heterogeneous catalysis mechanism and showed a great potential for the practical application of this technique in in situ TCE-contaminated groundwater remediation.
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Affiliation(s)
- Xiaoxin Ruan
- a State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process , East China University of Science and Technology , Shanghai 200237 , People's Republic of China
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Honetschlägerová L, Janouškovcová P, Kubal M, Sofer Z. Enhanced colloidal stability of nanoscale zero valent iron particles in the presence of sodium silicate water glass. Environ Technol 2015; 36:358-365. [PMID: 25323113 DOI: 10.1080/09593330.2014.977825] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A method for the stabilization of nanoscale zero valent iron (nZVI) particles using silica was developed. Stabilization can significantly improve the performance characteristics of currently available nZVI products containing agglomerated particles. In the first step of the method, the agglomerates were broken using a sonication. A subsequent stabilizing effect was brought about by the deposition of silica onto the surface of the nZVI particles. The method was tested on three commercially available nZVI suspensions which formed agglomerates with mean sizes ranging from 1000 to 5000 nm. The application of the method resulted in a significant reduction of the mean size of the agglomerates to the values from 100 to 200 nm. The stabilizing effect of silica was also evidenced using scanning electron microscopy, zeta potential measurements and sedimentation analysis. The introduction of typical groundwater ions did not significantly affect the colloidal stability of the treated nZVI suspensions. The results of this study indicate that the silica coating have the potential to protect nZVI against agglomeration.
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Affiliation(s)
- Lenka Honetschlägerová
- a Department of Environmental Chemistry , Institute of Chemical Technology Prague , Prague , Czech Republic
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Ndong LBB, Ibondou MP, Miao Z, Gu X, Lu S, Qiu Z, Sui Q, Mbadinga SM. Efficient dechlorination of chlorinated solvent pollutants under UV irradiation by using the synthesized TiO2 nano-sheets in aqueous phase. J Environ Sci (China) 2014; 26:1188-1194. [PMID: 25079650 DOI: 10.1016/s1001-0742(13)60541-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 10/29/2013] [Accepted: 11/08/2013] [Indexed: 06/03/2023]
Abstract
Titanium dioxide (TiO2), which is the widely used photo-catalyst, has been synthesized by simple hydrothermal solution containing tetrabutyl titanate and hydrofluoric acid. The synthesized product has been applied to photo-degradation in aqueous phase of chlorinated solvents, namely tetrachloroethene (PCE), trichloroethene (TCE) and 1,1,1-trichloroethane (TCA). The photo-degradation results revealed that the degradation of these harmful chemicals was better in UV/synthesized TiO2 system compared to UV/commercial P25 system and UV only system. The photo-catalytic efficiency of the synthesized TiO2 was 1.4, 1.8 and 3.0 folds higher compared to the commercial P25 for TCA, TCE and PCE degradation, respectively. Moreover, using nitrobenzene (NB) as a probe of hydroxyl radical (·OH), the degradation rate was better over UV/synthesized TiO2, suggesting the high concentration of ·OH generated in UV/synthesized TiO2 system. In addition, ·OH concentration was confirmed by the strong peak displayed in EPR analysis over UV/synthesized TiO2 system. The characterization result using XRD and TEM showed that the synthesized TiO2 was in anatase form and consisted of well-defined sheet-shaped structures having a rectangular outline with a thickness of 4 nm, side length of 50 nm and width of 33 nm and a surface 90.3 m(2)/g. XPS analysis revealed that ≡Ti-F bond was formed on the surface of the synthesized TiO2. The above results on both photocatalytic activity and the surface analysis demonstrated the good applicability of the synthesized TiO2 nano-sheets for the remediation of chlorinated solvent contaminated groundwater.
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Affiliation(s)
- Landry Biyoghe Bi Ndong
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China.
| | - Murielle Primaelle Ibondou
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Zhouwei Miao
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Xiaogang Gu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Shuguang Lu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China.
| | - Zhaofu Qiu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Qian Sui
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Serge Maurice Mbadinga
- State Key Laboratory of Bioreactor Engineering and Institute of Applied Chemistry, East China University of Science and Technology, Shanghai 200237, China
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Xie W, Yuan S, Mao X, Hu W, Liao P, Tong M, Alshawabkeh AN. Electrocatalytic activity of Pd-loaded Ti/TiO2 nanotubes cathode for TCE reduction in groundwater. Water Res 2013; 47:3573-82. [PMID: 23726693 PMCID: PMC6321742 DOI: 10.1016/j.watres.2013.04.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 03/29/2013] [Accepted: 04/01/2013] [Indexed: 05/11/2023]
Abstract
A novel cathode, Pd loaded Ti/TiO2 nanotubes (Pd-Ti/TiO2NTs), is synthesized for the electrocatalytic reduction of trichloroethylene (TCE) in groundwater. Pd nanoparticles are successfully loaded on TiO2 nanotubes which grow on Ti plate via anodization. Using Pd-Ti/TiO2NTs as the cathode in an undivided electrolytic cell, TCE is efficiently and quantitatively transformed to ethane. Under conditions of 100 mA and pH 7, the removal efficiency of TCE (21 mg/L) is up to 91% within 120 min, following pseudo-first-order kinetics with the rate constant of 0.019 min(-1). Reduction rates increase from 0.007 to 0.019 min(-1) with increasing the current from 20 to 100 mA, slightly decrease in the presence of 10 mM chloride or bicarbonate, and decline with increasing the concentrations of sulfite or sulfide. O2 generated at the anode slightly influences TCE reduction. At low currents, TCE is mainly reduced by direct electron transfer on the Pd-Ti/TiO2NT cathode. However, the contribution of Pd-catalytic hydrodechlorination, an indirect reduction mechanism, becomes significant with increasing the current. Compared with other common cathodes, i.e., Ti-based mixed metal oxides, graphite and Pd/Ti, Pd-Ti/TiO2NTs cathode shows superior performance for TCE reduction.
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Affiliation(s)
- Wenjing Xie
- State Key Lab of Biogeology and Environmental Geology, China University of Geosciences, 388 Lumo Road, Wuhan 430074, PR China
| | - Songhu Yuan
- State Key Lab of Biogeology and Environmental Geology, China University of Geosciences, 388 Lumo Road, Wuhan 430074, PR China
- Corresponding author. Tel.: +86 18971623175., , (S. Yuan)
| | - Xuhui Mao
- School of resource and Environmental Science, Wuhan University, 129 Luoyu Road, Wuhan 430079, PR China
| | - Wei Hu
- State Key Lab of Biogeology and Environmental Geology, China University of Geosciences, 388 Lumo Road, Wuhan 430074, PR China
| | - Peng Liao
- State Key Lab of Biogeology and Environmental Geology, China University of Geosciences, 388 Lumo Road, Wuhan 430074, PR China
| | - Man Tong
- State Key Lab of Biogeology and Environmental Geology, China University of Geosciences, 388 Lumo Road, Wuhan 430074, PR China
| | - Akram N. Alshawabkeh
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, MA 02115, United States
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Yuan S, Chen M, Mao X, Alshawabkeh AN. A three-electrode column for Pd-catalytic oxidation of TCE in groundwater with automatic pH-regulation and resistance to reduced sulfur compound foiling. Water Res 2013; 47:269-78. [PMID: 23121896 PMCID: PMC3581803 DOI: 10.1016/j.watres.2012.10.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2012] [Revised: 09/13/2012] [Accepted: 10/04/2012] [Indexed: 05/11/2023]
Abstract
A hybrid electrolysis and Pd-catalytic oxidation process is evaluated for degradation of trichloroethylene (TCE) in groundwater. A three-electrode, one anode and two cathodes, column is employed to automatically develop a low pH condition in the Pd vicinity and a neutral effluent. Simulated groundwater containing up to 5 mM bicarbonate can be acidified to below pH 4 in the Pd vicinity using a total of 60 mA with 20 mA passing through the third electrode. By packing 2 g of Pd/Al(2)O(3) pellets in the developed acidic region, the column efficiency for TCE oxidation in simulated groundwater (5.3 mg/L TCE) increases from 44 to 59 and 68% with increasing Fe(II) concentration from 0 to 5 and 10 mg/L, respectively. Different from Pd-catalytic hydrodechlorination under reducing conditions, this hybrid electrolysis and Pd-catalytic oxidation process is advantageous in controlling the fouling caused by reduced sulfur compounds (RSCs) because the in situ generated reactive oxidizing species, i.e., O(2), H(2)O(2) and OH, can oxidize RSCs to some extent. In particular, sulfite at concentrations less than 1 mM even greatly increases TCE oxidation by the production of SO(4)(•-), a strong oxidizing radical, and more OH.
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Affiliation(s)
- Songhu Yuan
- State Key Lab of Biogeology and Environmental Geology, China University of Geosciences, 388 Lumo Road, Wuhan, 430074, P. R. China
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
- Corresponding author. (S. Yuan), (A. Alshawabkeh)
| | - Mingjie Chen
- Atmospheric, Earth and Energy Division, Lawrence Livermore National Laboratory, P.O. Box 808, L-184, Livermore, CA 94550, United States
| | - Xuhui Mao
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Akram N. Alshawabkeh
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
- Corresponding author. (S. Yuan), (A. Alshawabkeh)
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