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Shahnazarova G, Al Hoda Al Bast N, Ramirez JC, Nogues J, Esteve J, Fraxedas J, Serra A, Esplandiu MJ, Sepulveda B. Fe/Au galvanic nanocells to generate self-sustained Fenton reactions without additives at neutral pH. MATERIALS HORIZONS 2024; 11:2206-2216. [PMID: 38415289 DOI: 10.1039/d3mh01935g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
The generation of reactive oxygen species (ROS) via the Fenton reaction has received significant attention for widespread applications. This reaction can be triggered by zero-valent metal nanoparticles by converting externally added H2O2 into hydroxyl radicals (˙OH) in acidic media. To avoid the addition of external additives or energy supply, developing self-sustained catalytic systems enabling onsite production of H2O2 at a neutral pH is crucial. Here, we present novel galvanic nanocells (GNCs) based on metallic Fe/Au bilayers on arrays of nanoporous silica nanostructures for the generation of self-sustained Fenton reactions. These GNCs exploit the large electrochemical potential difference between the Fe and Au layers to enable direct H2O2 production and efficient release of Fe2+ in water at neutral pH, thereby triggering the Fenton reaction. Additionally, the GNCs promote Fe2+/Fe3+ circulation and minimize side reactions that passivate the iron surface to enhance their reactivity. The capability to directly trigger the Fenton reaction in water at pH 7 is demonstrated by the fast degradation and mineralization of organic pollutants, by using tiny amounts of catalyst. The self-generated H2O2 and its transformation into ˙OH in a neutral environment provide a promising route not only in environmental remediation but also to produce therapeutic ROS and address the limitations of Fenton catalytic nanostructures.
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Affiliation(s)
- Gubakhanim Shahnazarova
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, E-08193 Barcelona, Spain.
- Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain
| | - Nour Al Hoda Al Bast
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, E-08193 Barcelona, Spain.
- Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain
| | - Jessica C Ramirez
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, E-08193 Barcelona, Spain.
- Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain
| | - Josep Nogues
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, E-08193 Barcelona, Spain.
- ICREA, Pg. Lluís Companys 23, 08010 Barcelona, Spain
| | - Jaume Esteve
- Instituto de Microelectrónica de Barcelona (IMB-CNM, CSIC), Barcelona, 08193, Spain.
| | - Jordi Fraxedas
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, E-08193 Barcelona, Spain.
| | - Albert Serra
- Grup d'Electrodeposició de Capes Primes i Nanoestructures (GE-CPN), Departament de Ciència de Materials i Química Física, Universitat de Barcelona, Martí i Franquès, 1, E-08028, Barcelona, Catalonia, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Barcelona, Catalonia, Spain
| | - Maria J Esplandiu
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, E-08193 Barcelona, Spain.
| | - Borja Sepulveda
- Instituto de Microelectrónica de Barcelona (IMB-CNM, CSIC), Barcelona, 08193, Spain.
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Yin X, Hua H, Dyer J, Landis R, Fennell D, Axe L. Degradation of chlorinated solvents with reactive iron minerals in subsurface sediments from redox transition zones. JOURNAL OF HAZARDOUS MATERIALS 2023; 445:130470. [PMID: 36493644 DOI: 10.1016/j.jhazmat.2022.130470] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 11/08/2022] [Accepted: 11/23/2022] [Indexed: 06/17/2023]
Abstract
Reactive iron (Fe) mineral coatings found in subsurface reduction-oxidation transition zones (RTZs) contribute to the attenuation of contaminants. An 18.3-m anoxic core was collected from the site, where constituents of concern (COCs) in groundwater included chlorinated solvents. Reactive Fe mineral coatings were found to be abundant in the RTZs. This research focused on evaluating reaction kinetics with anoxic sediments bearing ferrous mineral nano-coatings spiked with either tetrachloroethylene (PCE), trichloroethylene (TCE), or 1,4-dichlorobenzene (1,4-DCB). Reaction kinetics with RTZ sediments followed pseudo-first-order reactions for the three contaminants with 90% degradation achieved in less than 39 days. The second-order rate constants for the three COCs ranged from 6.20 × 10-4 to 1.73 × 10-3 Lg-1h-1 with pyrite (FeS2), 4.97 × 10-5 to 1.24 × 10-3 Lg-1h-1with mackinawite (FeS), 1.25 × 10-4 to 1.89 × 10-4 Lg-1h-1 with siderite (FeCO3), and 1.79 × 10-4 to 1.10 × 10-3 Lg-1h-1 with magnetite (Fe3O4). For these three chlorinated solvents, the trend for the rate constants followed: Fe(II) sulfide minerals > magnetite > siderite. The high reactivity of Fe mineral coatings is hypothesized to be due to the large surface areas of the nano-mineral coatings. As a result, these surfaces are expected to play an important role in the attenuation of chlorinated solvents in contaminated subsurface environments.
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Affiliation(s)
- Xin Yin
- Department of Civil and Environmental Engineering, New Jersey Institute of Technology, Newark, NJ 07032, USA
| | - Han Hua
- Department of Civil and Environmental Engineering, New Jersey Institute of Technology, Newark, NJ 07032, USA; Department of Civil, Construction & Environmental Engineering, University of New Mexico, Albuquerque, NM 87131, USA
| | - James Dyer
- Savannah River National Laboratory, Aiken, SC 29808, USA
| | | | - Donna Fennell
- Rutgers University, Department of Environmental Sciences, 14 College Farm Road, New Brunswick, NJ 08901, USA
| | - Lisa Axe
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technzhaology, Newark, NJ 07032, USA.
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Coupling Removal of P-Chloronitrobenzene and Its Reduction Products by Nano Iron Doped with Ni and FeOOH (nFe/Ni-FeOOH). MATERIALS 2022; 15:ma15051928. [PMID: 35269159 PMCID: PMC8911972 DOI: 10.3390/ma15051928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/15/2022] [Accepted: 03/01/2022] [Indexed: 02/04/2023]
Abstract
The removal of chlorinated pollutants from water by nanoparticles is a hot topic in the field of environmental engineering. In this work, a novel technique that includes the coupling effect of n-Fe/Ni and its transformation products (FeOOH) on the removal of p-chloronitrobenzene (p-CNB) and its reduction products, p-chloroaniline (p-CAN) and aniline (AN), were investigated. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were employed to characterize the nano-iron before and after the reaction. The results show that Fe0 is mainly oxidized into lath-like lepidocrocite (γ-FeOOH) and needle-like goethite (α-FeOOH) after 8 h of reaction. The coupling removal process and the mechanism are as follows: Fe0 provides electrons to reduce p-CNB to p-CAN and then dechlorinates p-CAN to AN under the catalysis of Ni. Meanwhile, Fe0 is oxidized to FeOOH by the dissolved oxygen and H2O. AN is then adsorbed by FeOOH. Finally, p-CNB, p-CAN, and AN were completely removed from the water. In the pH range between 3 and 7, p-CAN can be completely dechlorinated by n-Fe/Ni within 20 min, while AN can be nearly 100% adsorbed by FeOOH within 36 h. When the temperature ranges from 15 °C to 35 °C, the dechlorination rate of p-CAN and the removal rate of AN are less affected by temperature. This study provides guidance on the thorough remediation of water bodies polluted by chlorinated organics.
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Nie M, Li Y, Dong Y, Song Z, Zhao C, Chen S. Mechanochemical degradation of hexachlorobenzene with a combined additive of SiC and Fe. Chem Eng Res Des 2022. [DOI: 10.1016/j.cherd.2021.10.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Wang P, Fu F, Liu T. A review of the new multifunctional nano zero-valent iron composites for wastewater treatment: Emergence, preparation, optimization and mechanism. CHEMOSPHERE 2021; 285:131435. [PMID: 34256206 DOI: 10.1016/j.chemosphere.2021.131435] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 06/30/2021] [Accepted: 07/02/2021] [Indexed: 06/13/2023]
Abstract
Nano zero-valent iron (NZVI) with high chemical reactivity and environmental friendliness had recently become one of the most efficient technologies for wastewater restoration. However, the unitary NZVI system had not met practical requirements for wastewater treatments. Expectantly, the development of NZVI would prefer multifunctional NZVI-based composites, which could be prepared and optimized by the combined methods and technologies. Consequently, a systematic and comprehensive summary from the perspective of multifunctional NZVI-composite had been conducted. The results demonstrated that the advantages of various systems were integrated by multifunctional NZVI-composite systems with a more significant performance of pollutant removal than those of the bare NZVI and its composites. Simultaneously, characteristics of the product prepared by the incorporation of numerous methods were superior to those by a simple method, resulting in the increase of the entirety efficiency. By comparison with other preparation methods, the ball milling method with higher production and field application potential was worthy of attention. After combining multiple technologies, the effect of NZVI and its composite systems could be dramatically strengthened. Preparation technology parameters and treatment effect of contaminants could be further optimized using more comprehensive experimental designs and mathematical models. The mechanism of the multifunctional NZVI system for contaminants treatment was primarily focused on adsorption, oxidation, reduction and co-precipitation. Multiple techniques were combined to enhance the dispersion, alleviating passivation, accelerating electron transfer efficiency or mass transfer action for optimizing the effect of NZVI composites.
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Affiliation(s)
- Peng Wang
- Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, 300387, Tianjin, PR China; School of Geography and Environmental Sciences, Tianjin Normal University, Tianjin, 300387, Tianjin, PR China
| | - Fugang Fu
- PowerChina Guiyang Engineering Corporation Limited, 300387, Guiyang, PR China
| | - Tingyi Liu
- Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, 300387, Tianjin, PR China.
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Cheng H, Zhu Q, Wang A, Weng M, Xing Z. Composite of chitosan and bentonite cladding Fe-Al bimetal: Effective removal of nitrate and by-products from wastewater. ENVIRONMENTAL RESEARCH 2020; 184:109336. [PMID: 32182480 DOI: 10.1016/j.envres.2020.109336] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 12/20/2019] [Accepted: 03/02/2020] [Indexed: 06/10/2023]
Abstract
Chitosan was used as crosslinking agent to load bimetal particles onto bentonite. The Fe-Al bimetal chitosan bentonite (Fe-Al bimetal @ bent) complex was prepared for the efficient removal of nitrate from wastewater and its by-products at low temperature. The samples were characterized by Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), X-Ray Diffraction (XRD), Zeta potential, X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET) surface area and Energy Dispersive X-ray Detector (EDX). SEM and EDX showed that Fe0 was deposited on the surface of aluminum, the Fe-Al bimetal were surrounded by chitosan and bentonite. XRD showed that Al can effectively protect the reactivity of Fe. The experimental results of nitrate removal showed that pH was the main factor affecting on nitrate removal rate and performance. The removal efficiency of nitrate wastewater with a concentration of 50 mg/L was approximately 90% in 60min. Fe-Al bimetal @ bent has better nitrate removal performance and faster reduction rate at low temperature(2-7 °C) than normal temperature (25 °C). The reason was that chitosan, bentonite and bimetal have excellent synergistic effect. It can effectively improve the reaction rate, pH buffering capacity, reduce secondary pollution and total nitrogen (TN). Fe-Al bimetal @ bent has better N2 selectivity than Fe-Al bimetal.
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Affiliation(s)
- Houming Cheng
- School of Chemistry and Materials Science, Heilongjiang University, Key Laboratory of Chemical Engineering Process & Technology for High-efficiency Conversion, Harbin, 150080, China
| | - Qi Zhu
- School of Chemistry and Materials Science, Heilongjiang University, Key Laboratory of Chemical Engineering Process & Technology for High-efficiency Conversion, Harbin, 150080, China.
| | - Aiwen Wang
- School of Chemistry and Materials Science, Heilongjiang University, Key Laboratory of Chemical Engineering Process & Technology for High-efficiency Conversion, Harbin, 150080, China
| | - Mingmei Weng
- School of Chemistry and Materials Science, Heilongjiang University, Key Laboratory of Chemical Engineering Process & Technology for High-efficiency Conversion, Harbin, 150080, China
| | - Zipeng Xing
- School of Chemistry and Materials Science, Heilongjiang University, Key Laboratory of Chemical Engineering Process & Technology for High-efficiency Conversion, Harbin, 150080, China.
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Dong Y, Li Y, Zhao C, Feng Y, Chen S, Dong Y. Mechanism of the rapid mechanochemical degradation of hexachlorobenzene with silicon carbide as an additive. JOURNAL OF HAZARDOUS MATERIALS 2019; 379:120653. [PMID: 31302587 DOI: 10.1016/j.jhazmat.2019.05.046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Revised: 05/17/2019] [Accepted: 05/20/2019] [Indexed: 06/10/2023]
Abstract
Mechanochemical treatment (MCT) is a promising method for degrading hexachlorobenzene (HCB). Silicon carbide (SiC) was proposed in this study as a new additive to accelerate the reaction in MCT. The high performance of SiC was verified, and the relevant mechanism was explored. Graphite, amorphous carbon, CCl4, SiO2, and water-soluble chloride were confirmed as predominant products in the proposed method, and only trace-level low chlorinated benzenes were detected. The reaction pathway was revealed as follows: under the attack of free electrons, chlorine atoms were shed from the benzene rings of HCB to form Cl· radicals, which reacted with SiC to form SiCl4 and CCl4 and with the in situ-generated iron powder to produce Fe-based chloride. The left benzene rings were translated to graphite and amorphous carbon. As an intermediate product, SiCl4 further reacted with water vapor in the atmosphere to produce SiO2 and HCl. The in situ-generated iron powder could not remarkably accelerate the degradation reaction. The major contribution of SiC was the supply of free electrons to trigger the reaction. Two sources of free electrons were discussed. Friction heat resulting from hard SiC also contributed to the endothermic reaction of HCB degradation.
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Affiliation(s)
- Yan Dong
- National Engineering Laboratory of Coal-fired Pollutants Emission Reduction, School of Energy and Power Engineering, Shandong University, 17923 Jingshi Road, Jinan, 250061, China
| | - Yuzhong Li
- National Engineering Laboratory of Coal-fired Pollutants Emission Reduction, School of Energy and Power Engineering, Shandong University, 17923 Jingshi Road, Jinan, 250061, China.
| | - Cheng Zhao
- National Engineering Laboratory of Coal-fired Pollutants Emission Reduction, School of Energy and Power Engineering, Shandong University, 17923 Jingshi Road, Jinan, 250061, China
| | - Yupeng Feng
- National Engineering Laboratory of Coal-fired Pollutants Emission Reduction, School of Energy and Power Engineering, Shandong University, 17923 Jingshi Road, Jinan, 250061, China; Shandong Low Carbon Expert Sci. & Tech. Co. Ltd., 54 Maanshan Road, Jinan, 250002, China
| | - Shouyan Chen
- National Engineering Laboratory of Coal-fired Pollutants Emission Reduction, School of Energy and Power Engineering, Shandong University, 17923 Jingshi Road, Jinan, 250061, China; Shared Laboratory of Energy and Environment, Shandong University Science Park, 54 Maanshan Road, Jinan, 250002, China
| | - Yong Dong
- National Engineering Laboratory of Coal-fired Pollutants Emission Reduction, School of Energy and Power Engineering, Shandong University, 17923 Jingshi Road, Jinan, 250061, China
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8
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Yang Z, Zhang X, Pu S, Ni R, Lin Y, Liu Y. Novel Fenton-like system (Mg/Fe-O 2) for degradation of 4-chlorophenol. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 250:906-913. [PMID: 31085477 DOI: 10.1016/j.envpol.2019.04.096] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Revised: 04/04/2019] [Accepted: 04/18/2019] [Indexed: 06/09/2023]
Abstract
A novel heterogeneous Fenton-like system (Mg/Fe-O2) which could directly convert oxygen (O2) to hydrogen peroxide/hydroxyl radicals (H2O2/•OH) was developed and used to degrade 4-chlorophenol. The Mg/Fe bimetallic particles were prepared by chemical displacement process and characterized by XRD, SEM and TEM. The in situ continuous production of H2O2/•OH and the effect of the mole ratio of Mg to Fe in the Mg/Fe bimetallic particles and the operating parameters on the degradation 4-chlorophenol in Mg/Fe-O2 system were investigated in detail. It was found that the Mg/Fe bimetallic particles with the mole ratio of Mg to Fe of 32:1 had the best performance for the 4-chlorophenol degradation and the maximum cumulative concentration of H2O2, the degradation efficiency of 4-chlorophenol and the removal efficiency of TOC in Mg/Fe-O2 system were 34.5 mg/L, 100% and 91.8%, respectively, at pH 3, O2 flow rate 400 mL/min, dosage of Mg/Fe bimetallic particles 2 g/L, 4-chlorophenol initial concentration 50 mg/L and reaction time 60 min. It was revealed by radical scavenging experiments that •OH, particularly the surface-bound •OH, were the predominant reactive oxygen species in Mg/Fe-O2 system for the degradation of 4-chlorophenol. The main intermediates of 4-chlorophenol degradation were detected by high-resolution liquid chromatography equipped with time-of-flight mass spectrometry (HRLC-ToF-MS) and ion chromatography (IC). Based the results of control experiments and the electrochemical tests, the possible pathway and mechanism of 4-chlorophenol degradation in Mg/Fe-O2 system were tentatively proposed.
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Affiliation(s)
- Zhao Yang
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610066, China
| | - Xu Zhang
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610066, China
| | - Siji Pu
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610066, China
| | - Renxiang Ni
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610066, China
| | - Ying Lin
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610066, China
| | - Yong Liu
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610066, China; Key Laboratory of Treatment for Special Wastewater of Sichuan Province Higher Education System, Sichuan, Chengdu, 610066, China.
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9
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Garbou AM, Liu M, Zou S, Yestrebsky CL. Degradation kinetics of hexachlorobenzene over zero-valent magnesium/graphite in protic solvent system and modeling of degradation pathways using density functional theory. CHEMOSPHERE 2019; 222:195-204. [PMID: 30708153 DOI: 10.1016/j.chemosphere.2019.01.134] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 12/23/2018] [Accepted: 01/23/2019] [Indexed: 06/09/2023]
Abstract
Hexachlorobenzene (HCB), like many chlorinated organic compounds, has accumulated in the environment from agricultural and industrial activity. Because of its health risks and adverse impact on various ecosystems, remediation of this contaminant is of vital concern. The objective of this study is to evaluate the proficiency of activated magnesium metal in a protic solvent system to accomplish reductive dechlorination of HCB. Experimental results were compared with those predicted by quantum chemical calculations based on Density Functional Theory (DFT). Multivariate analysis detected complete degradation of HCB within 30 min at room temperature, the reaction having a rate constant of 0.222 min-1. Dechlorination was hypothesized to proceed via an ionic mechanism; the main dechlorination pathways of HCB in 1:1 ethanol:ethyl lactate were HCB → PCBz → 1,2,4,5-TCB; 1,2,3,5-TCB → 1,2,4-TriCB; 1,3,5-TriCB → 1,4-DiCB; 1,3-DiCB. The direct relationship between the decreasing number of Cl substituents and dechlorination reaction kinetics agrees with the ΔG values predicted by the computational model. This methodology shows promise for the development of a practical and sustainable field application for the remediation of other chlorinated aromatic compounds.
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Affiliation(s)
- Amel M Garbou
- Environmental Chemistry Laboratory, University of Central Florida, 4000 Central Florida Blvd., Orlando, FL 32816, United States
| | - Muqiong Liu
- Department of Chemistry, University of Central Florida, 4000 Central Florida Blvd., Orlando, FL 32816, United States
| | - Shengli Zou
- Department of Chemistry, University of Central Florida, 4000 Central Florida Blvd., Orlando, FL 32816, United States
| | - Cherie L Yestrebsky
- Environmental Chemistry Laboratory, University of Central Florida, 4000 Central Florida Blvd., Orlando, FL 32816, United States.
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Mass spectrometric imaging reveals photocatalytic degradation intermediates of aromatic organochlorines resulting from interfacial photoelectron transfer and hydroxyl radical abstraction on semiconductor nanoparticles. Anal Chim Acta 2019; 1054:104-113. [DOI: 10.1016/j.aca.2018.12.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 11/07/2018] [Accepted: 12/11/2018] [Indexed: 11/21/2022]
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Jiang Y, Shang Y, Yu S, Liu J. Dechlorination of Hexachlorobenzene in Contaminated Soils Using a Nanometallic Al/CaO Dispersion Mixture: Optimization through Response Surface Methodology. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15050872. [PMID: 29702570 PMCID: PMC5981911 DOI: 10.3390/ijerph15050872] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 04/18/2018] [Accepted: 04/18/2018] [Indexed: 11/27/2022]
Abstract
Hexachlorobenzene (HCB) contamination of soils remains a significant environmental challenge all over the world. Reductive stabilization is a developing technology that can decompose the HCB with a dechlorination process. A nanometallic Al/CaO (n-Al/CaO) dispersion mixture was developed utilizing ball-milling technology in this study. The dechlorination efficiency of HCB in contaminated soils by the n-Al/CaO grinding treatment was evaluated. Response surface methodology (RSM) was employed to investigate the effects of three variables (soil moisture content, n-Al/CaO dosage and grinding time) and the interactions between these variables under the Box-Behnken Design (BBD). A high regression coefficient value (R2 = 0.9807) and low p value (<0.0001) of the quadratic model indicated that the model was accurate in predicting the experimental results. The optimal soil moisture content, n-Al/CaO dosage, and grinding time were found to be 7% (m/m), 17.7% (m/m), and 24 h, respectively, in the experimental ranges and levels. Under optimal conditions, the dechlorination efficiency was 80%. The intermediate product analysis indicated that dechlorination was the process by stepwise loss of chloride atoms. The main pathway observed within 24 h was HCB → pentachlorobenzene (PeCB) → 1,2,3,4-tetrachlorobenzene (TeCB) and 1,2,4,5-TeCB. The results indicated that the moderate soil moisture content was crucial for the hydrodechlorination of HCB. A probable mechanism was proposed wherein water acted like a hydrogen donor and promoted the hydrodechlorination process. The potential application of n-Al/CaO is an environmentally-friendly and cost-effective option for decontamination of HCB-contaminated soils.
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Affiliation(s)
- Yuhui Jiang
- Key Laboratory for Solid Waste Management and Environment Safety (Tsinghua University), Ministry of Education of China, Tsinghua University, Beijing 100084, China.
| | - Yixuan Shang
- Key Laboratory for Solid Waste Management and Environment Safety (Tsinghua University), Ministry of Education of China, Tsinghua University, Beijing 100084, China.
| | - Shuyao Yu
- Key Laboratory for Solid Waste Management and Environment Safety (Tsinghua University), Ministry of Education of China, Tsinghua University, Beijing 100084, China.
| | - Jianguo Liu
- Key Laboratory for Solid Waste Management and Environment Safety (Tsinghua University), Ministry of Education of China, Tsinghua University, Beijing 100084, China.
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12
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Dong H, Jiang Z, Deng J, Zhang C, Cheng Y, Hou K, Zhang L, Tang L, Zeng G. Physicochemical transformation of Fe/Ni bimetallic nanoparticles during aging in simulated groundwater and the consequent effect on contaminant removal. WATER RESEARCH 2018; 129:51-57. [PMID: 29128681 DOI: 10.1016/j.watres.2017.11.002] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 10/28/2017] [Accepted: 11/01/2017] [Indexed: 06/07/2023]
Abstract
To assess the fate and long-term reactivity of bimetallic nanoparticles used in groundwater remediation, it is important to trace the physicochemical transformation of nanoparticles during aging in water. This study investigated the short-term (within 5 d) and long-term (up to 90 d) aging process of Fe/Ni bimetallic nanoparticles (Fe/Ni BNPs) in simulated groundwater and the consequent effect on the particle reactivity. Results indicate that the morphological, compositional and structural transformation of Fe/Ni BNPs happened during the aging. In the 5-d short-term aging, Fe0 corrosion occurred rapidly and was transformed to ferrous ions which were adsorbed onto the surface of Fe/Ni BNPs, accompanied by the elevation of solution pH and the negative redox potential. In the long-term aging, scanning electron microscopy (SEM) images show that the particles transformed from spherical to rod-like and further to sheet-like and needle-like. X-ray diffraction (XRD) analysis reveals that the main aging product was magnetite (Fe3O4) and/or maghemite (γ-Fe2O3) after aging for 60-90 d. Energy dispersive spectrometer (EDS) analysis demonstrates that the mass ratio of Fe/Ni increased with aging, revealing that Ni were possibly gradually entrapped and covered by the iron oxides. Besides, the release of Ni into solution was also detected during the aging. The reactivity of the aged Fe/Ni BNPs was examined by studying its performance in tetracycline (TC) removal. The aged Fe/Ni BNPs within 2 d kept similar removal efficiency of TC as the fresh particles. However, the removal efficiency of TC by Fe/Ni BNPs aged for 5-15 d dropped by 20-50% due to aggregation and oxidation of particles, and the removal efficiency further decreased slowly with the prolongation of aging time up to 90 d. This reveals that Fe/Ni BNPs were vulnerable to passivation in water environments.
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Affiliation(s)
- Haoran Dong
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China.
| | - Zhao Jiang
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
| | - Junmin Deng
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
| | - Cong Zhang
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
| | - Yujun Cheng
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
| | - Kunjie Hou
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
| | - Lihua Zhang
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
| | - Lin Tang
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
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13
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Katayama Y, Aoyagi M, Matsumoto T, Harada H, Simion AM, Egashira N, Mitoma Y, Simion C. Hydrodehalogenation of hexachloro- and hexabromobenzene by metallic calcium in ethanol, in the presence of Rh/C catalyst. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:591-597. [PMID: 27743324 DOI: 10.1007/s11356-016-7785-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 09/26/2016] [Indexed: 06/06/2023]
Abstract
Both hexachlorobenzene and hexabromobenzene were successfully hydrodehalogenated to the monohalogenated derivative and ultimately to benzene (which was subsequently reduced to cyclohexane) using a mixture of metallic Ca, ethanol, and Rh/C, by simple stirring in diethyl ether, at room or mild temperature (60 °C). Various experiments were performed in order to assess the role of the solvent and Rh/C catalyst, as well as for elucidating the reaction pathway.
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Affiliation(s)
- Yumi Katayama
- Department of Biological System Sciences, Graduate School of Comprehensive Scientific Research, Prefectural University of Hiroshima, 562 Nanatsuka-Cho, Shobara City, Hiroshima, 727-0023, Japan
| | - Mitsuru Aoyagi
- Department of Environmental Sciences, Prefectural University of Hiroshima, 562 Nanatsuka-Cho, Shobara City, Hiroshima, 727-0023, Japan
| | - Takuya Matsumoto
- Department of Environmental Sciences, Prefectural University of Hiroshima, 562 Nanatsuka-Cho, Shobara City, Hiroshima, 727-0023, Japan
| | - Hiroyuki Harada
- Department of Environmental Sciences, Prefectural University of Hiroshima, 562 Nanatsuka-Cho, Shobara City, Hiroshima, 727-0023, Japan
| | - Alina M Simion
- Department of Organic Chemistry, Politehnica University of Bucharest, 060042, Bucharest, Romania
| | - Naoyoshi Egashira
- Department of Environmental Sciences, Prefectural University of Hiroshima, 562 Nanatsuka-Cho, Shobara City, Hiroshima, 727-0023, Japan
| | - Yoshiharu Mitoma
- Department of Environmental Sciences, Prefectural University of Hiroshima, 562 Nanatsuka-Cho, Shobara City, Hiroshima, 727-0023, Japan.
| | - Cristian Simion
- Department of Organic Chemistry, Politehnica University of Bucharest, 060042, Bucharest, Romania.
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14
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Mitoma Y, Katayama Y, Simion AM, Harada H, Kakeda M, Egashira N, Simion C. Considerations on the mechanism of Ca/ethanol/Pd/C assisted hydrodechlorination of chlorinated aromatic substrates. CHEMOSPHERE 2016; 164:92-97. [PMID: 27580262 DOI: 10.1016/j.chemosphere.2016.08.088] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 07/28/2016] [Accepted: 08/18/2016] [Indexed: 06/06/2023]
Abstract
In order to elucidate the metal-alcohol hydrodechlorination reaction mechanism, several experiments using chloroanisoles as substrates were performed. Thus, chloroanisoles were stirred at 60 °C for 2 h with a mixture of Ca, methanol and various reduction catalysts. The use of deuterated methanol and zeta potential experiments offered supplementary informations, pointing toward a probable radicalic mechanism that occurs on Ca and Pd/C surfaces.
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Affiliation(s)
- Yoshiharu Mitoma
- Department of Environmental Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, 562 Nanatsuka-Cho, Shobara City, Hiroshima, 727-0023, Japan.
| | - Yumi Katayama
- Department of Environmental Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, 562 Nanatsuka-Cho, Shobara City, Hiroshima, 727-0023, Japan
| | - Alina M Simion
- Politehnica University of Bucharest, Department of Organic Chemistry, 060042, Bucharest, Romania
| | - Hiroyuki Harada
- Department of Environmental Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, 562 Nanatsuka-Cho, Shobara City, Hiroshima, 727-0023, Japan
| | - Mitsunori Kakeda
- Department of Environmental Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, 562 Nanatsuka-Cho, Shobara City, Hiroshima, 727-0023, Japan
| | - Naoyoshi Egashira
- Department of Environmental Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, 562 Nanatsuka-Cho, Shobara City, Hiroshima, 727-0023, Japan
| | - Cristian Simion
- Politehnica University of Bucharest, Department of Organic Chemistry, 060042, Bucharest, Romania.
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15
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Wang X, Liu P, Fu M, Ma J, Ning P. Novel sequential process for enhanced dye synergistic degradation based on nano zero-valent iron and potassium permanganate. CHEMOSPHERE 2016; 155:39-47. [PMID: 27105151 DOI: 10.1016/j.chemosphere.2016.04.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 03/14/2016] [Accepted: 04/06/2016] [Indexed: 06/05/2023]
Abstract
A novel synergistic technology based on nano zero-valent iron (NZVI) and potassium permanganate (KMnO4) was developed for treatment of dye wastewater. The synergistic technology was significantly superior, where above 99% of methylene blue (MB) was removed, comparatively, removal efficiencies of MB with the sole technology of NZVI and KMnO4 at pH 6.39 being 52.9% and 63.1%, respectively. The advantages of this technology include (1) the in situ formed materials (manganese (hydr)oxides, iron hydroxides and MnFe oxide), resulting in the stable and high removal efficiency of MB and (2) high removal capacity in a wide range of pH value. Compared with simultaneous addition system of NZVI and KMnO4, MB removal was remarkably improved by sequential addition system, especially when KMnO4 addition time was optimized at 20 min. Analyses of crystal structure (XRD), morphological difference (FE-SEM), element valence and chemical groups (XPS) of NZVI before and after reaction had confirmed the formation of in situ materials, which obviously enhanced removal of MB by oxidation and adsorption. More importantly, the roles of in situ formed materials and degradation mechanism were innovatively investigated, and the results suggested that NCH3 bond of MB molecule was attacked by oxidants (KMnO4 and in situ manganese (hydr)oxides) at position C1 and C9, resulting in cleavage of chromophore. This study provides new insights about an applicable technology for treatment of dye wastewater.
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Affiliation(s)
- Xiangyu Wang
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Peng Liu
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Minglai Fu
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Jun Ma
- School of Municipal and Environmental Engineering, State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Ping Ning
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China.
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16
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Cheng Z, Fu F, Dionysiou DD, Tang B. Adsorption, oxidation, and reduction behavior of arsenic in the removal of aqueous As(III) by mesoporous Fe/Al bimetallic particles. WATER RESEARCH 2016; 96:22-31. [PMID: 27016635 DOI: 10.1016/j.watres.2016.03.020] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 03/07/2016] [Accepted: 03/08/2016] [Indexed: 05/21/2023]
Abstract
In this study, mesoporous iron/aluminum (Fe/Al) bimetallic particles were synthesized and employed for the removal of aqueous As(III). Scanning electron microscopy and energy dispersive spectroscopy (SEM-EDS), Brunauer-Emmett-Teller (BET) analysis method, Vibrating-sample magnetometry (VSM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR) were employed to characterize the Fe/Al bimetals before and after reaction with As(III). The physical properties, compositions, and structures of Fe/Al bimetallic particles as well as the As(III) removal mechanism were investigated. The characterization of the bimetallic particles after the reaction has revealed the removal of As(III) is a complex process including surface adsorption and oxidation, and intraparticle reduction. The good As(III) removal capability and stability of the Fe/Al bimetallic particles exhibited its great potential as an effective and environmental friendly agent for As(III) removal from water.
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Affiliation(s)
- Zihang Cheng
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Fenglian Fu
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China.
| | - Dionysios D Dionysiou
- Environmental Engineering and Science Program, Department of Biomedical, Chemical and Environmental Engineering (DBCEE), University of Cincinnati, OH, 45221-0012, USA
| | - Bing Tang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
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17
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Fu F, Cheng Z, Dionysiou DD, Tang B. Fe/Al bimetallic particles for the fast and highly efficient removal of Cr(VI) over a wide pH range: Performance and mechanism. JOURNAL OF HAZARDOUS MATERIALS 2015; 298:261-269. [PMID: 26073381 DOI: 10.1016/j.jhazmat.2015.05.047] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Revised: 05/15/2015] [Accepted: 05/27/2015] [Indexed: 06/04/2023]
Abstract
The iron/aluminum (Fe/Al) bimetallic particles with high efficiency for the removal of Cr(VI) were prepared. Fe/Al bimetallic particles were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), SEM mapping, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). SEM mapping showed that the core of bimetal was Al, and the planting Fe was deposited on the surface of Al. In acidic and neutral conditions, Fe/Al bimetal can completely remove Cr(VI) from wastewater in 20 min. Even at pH 11.0, the Cr(VI) removal efficiency achieved was 93.5%. Galvanic cell effect and high specific surface area are the main reasons for the enhanced removal of Cr(VI) by bimetallic particles. There were no iron ions released in solutions at pH values ranging from 3.0 to 11.0. The released Al(3+) ions concentrations in acidic and neutral conditions were all less than 0.2mg/L. The bimetal can be used 4 times without losing activity at initial pH 3.0. XPS indicated that the removed Cr(VI) was immobilized via the formation of Cr(III) hydroxide and Cr(III)-Fe(III) hydroxide/oxyhydroxide on the surface of Fe/Al bimetal. The Fe/Al bimetallic particles are promising for further testing for the rapid and effective removal of contaminants from water.
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Affiliation(s)
- Fenglian Fu
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China; Environmental Engineering and Science Program, Department of Biomedical, Chemical and Environmental Engineering (DBCEE), University of Cincinnati, OH 45221-0012, USA.
| | - Zihang Cheng
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Dionysios D Dionysiou
- Environmental Engineering and Science Program, Department of Biomedical, Chemical and Environmental Engineering (DBCEE), University of Cincinnati, OH 45221-0012, USA.
| | - Bing Tang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
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18
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Fu F, Cheng Z, Lu J. Synthesis and use of bimetals and bimetal oxides in contaminants removal from water: a review. RSC Adv 2015. [DOI: 10.1039/c5ra13067k] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
This paper gives an overview of the recent advances of the synthesis methods of bimetals and bimetal oxides and applying them in contaminant removal from water.
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Affiliation(s)
- Fenglian Fu
- School of Environmental Science and Engineering
- Guangdong University of Technology
- Guangzhou 510006
- PR China
| | - Zihang Cheng
- School of Environmental Science and Engineering
- Guangdong University of Technology
- Guangzhou 510006
- PR China
| | - Jianwei Lu
- School of Environmental Science and Engineering
- Guangdong University of Technology
- Guangzhou 510006
- PR China
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19
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Liu T, Li X, Waite TD. Depassivation of aged Fe 0 by divalent cations: correlation between contaminant degradation and surface complexation constants. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:14564-14571. [PMID: 25383907 DOI: 10.1021/es503777a] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The dechlorination of trichloroethylene (TCE) by aged Fe(0) in the presence of a series of divalent cations was investigated with the result that while no significant degradation of TCE was observed in Milli-Q water or in solutions of Ba(2+), Sr(2+), or Ca(2+), very effective TCE removal was observed in solutions containing Mg(2+), Mn(2+), Co(2+), Fe(2+), Ni(2+), Zn(2+), Cu(2+), or Pb(2+). The rate constants of TCE removal in the presence of particular cations were positively correlated to the log K representing the affinity of the cations for hydrous ferric oxide (HFO) surface sites though the treatments with Co(2+) and Ni(2+) were found to provide particularly strong enhancement in TCE degradation rate. The extent of Fe(II) release to solution also increased with increase in log K, while the solution pH from both experimental measurement and thermodynamic calculation decreased with increasing log K. While the peak areas of Fe and O XPS spectra of the passivated ZVI in the presence of Ba(2+), Sr(2+), and Ca(2+) were very close to those in Milli-Q water, very significant increases in surface Fe and O (and OH) were observed in solutions of Mg(2+), Mn(2+), Co(2+), Fe(2+), Ni(2+), Zn(2+), Cu(2+) and Pb(2+), revealing that the surface oxide layer dissolution is consistent with the recovery of aged Fe(0) with respect to TCE degradation. The depassivation process is proposed to involve (i) surface complexation of cations on surface coatings of aged Fe(0), (ii) dissolution of the hydrated surface as a consequence of magnetite exposure, and (iii) transport of electrons from underlying Fe(0) via magnetite to TCE, resulting in TCE dechlorination and, for some cations (Co(2+), Ni(2+), Cu(2+), and Pb(2+)), reduction to their zero or +1 valence state (with potential for these reduced metals to enhance TCE degradation).
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Affiliation(s)
- Tongxu Liu
- Guangdong Key Lab. of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences , Guangzhou 510650, People's Republic of China
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20
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Chemical dechlorination of hexachlorobenzene with polyethylene glycol and hydroxide: dominant effect of temperature and ionic potential. Sci Rep 2014; 4:6305. [PMID: 25200551 PMCID: PMC4158325 DOI: 10.1038/srep06305] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 08/15/2014] [Indexed: 01/28/2023] Open
Abstract
Persistent organic pollutants (POPs) originating from POP waste are playing an increasingly important role in the elevation of regional POP levels. In this study we realized the complete dechlorination of high concentration hexachlorobenzene (HCB) waste in the presence of polyethylene glycol and hydroxide, rather than using conventional high temperature incineration. Here, we demonstrate the dominant effect of temperature and hydroxide on HCB dechlorination in this process. Complete dechlorination of HCB was only observed at temperature about 200°C or above within 4 h reaction, and the apparent activation energy of this process was 43.1 kJ/mol. The alkalinity of hydroxides had notable effects on HCB dechlorination, and there was a considerable linear relationship between the natural logarithm of the HCB dechlorination rate constant and square root of the ionic potential of metal cation (R2 = 0.9997, p = 0.0081, n = 3). This study highlights a promising technology to realize complete dechlorination of POP waste, especially at high concentrations, in the presence of PEG in conjunction with hydroxide.
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21
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Xiao Y, Jiang J. Base-catalyzed decomposition of hexachlorobenzene: effect on dechlorination efficiency of different hydrogen donors, alkalis and catalysts. RSC Adv 2014. [DOI: 10.1039/c4ra00386a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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22
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Cai S, Wang D, Niu Z, Li Y. Progress in organic reactions catalyzed by bimetallic nanomaterials. CHINESE JOURNAL OF CATALYSIS 2013. [DOI: 10.1016/s1872-2067(12)60701-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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