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Jungcharoen P, Mekhin P, Seelaphat J, Thongbai P, Ekprasert J. Chromium (VI) removal by magnetite nanoparticles immobilized with extracellular polymeric substances extracted from Lysinibacillus sp. WH. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2024; 96:e11102. [PMID: 39155050 DOI: 10.1002/wer.11102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 07/17/2024] [Accepted: 07/30/2024] [Indexed: 08/20/2024]
Abstract
Magnetite nanoparticles (nano-Fe3O4) and nano-Fe3O4 immobilized with bacterial extracellular polymeric substances (EPSs) extracted from Lysinibacillus sp. WH (Fe3O4/bact) were comparatively studied for the removal of Cr (VI) ions from aqueous solution in batch study. The objectives were to explore the removal of Cr (VI) efficiency by nano-Fe3O4 and Fe3O4/bact under varying bacterial concentrations at a range of acidic pH. Results indicated that 150 ppm Cr (VI) could be effectively removed by 5 g/L of nano-Fe3O4 at pH 4, with the efficiency of 89.2 ± 12%. The equilibrium time, determined by a pseudo-second-order model (R2 = 0.9983), was after 5 h, indicating chemical adsorption. The Cr (VI) removal by the nano-Fe3O4 immobilized with bacterial EPS was effective and steady under a wide range of acidic conditions although bacterial EPS has an alkaline nature. Here, we are the first to demonstrate that Cr (VI) removal efficiency by different concentrations of EPS was not significantly different, suggesting EPS concentration is possibly not the most crucial factor to be optimized for Cr (VI) removal in the future. This study shows the potential application of nano-Fe3O4 immobilized with bacterial EPS for wastewater treatment. PRACTITIONER POINTS: The equilibrium time for magnetite nanoparticles to remove Cr (VI) is 5 h, suggesting chemical adsorption. The Cr (VI) removal efficiency of either magnetite nanoparticles or bacterial EPS is stable under a wide range of acidic conditions. Magnetite nanoparticles immobilized with bacterial EPS extracted from Lysinibacillus sp. WH has a potential application for Cr (VI) removal in wastewater.
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Affiliation(s)
- Phoomipat Jungcharoen
- Department of Environmental Engineering, Faculty of Engineering and Research Center for Environmental and Hazardous Substance Management, Khon Kaen University, Khon Kaen, Thailand
- Department of Environmental Engineering, King Mongkut's University of Technology Thonburi, Tungkru, Bangkok, Thailand
| | - Phawida Mekhin
- Department of Environmental Engineering, Faculty of Engineering and Research Center for Environmental and Hazardous Substance Management, Khon Kaen University, Khon Kaen, Thailand
| | - Jiratchaya Seelaphat
- Department of Environmental Engineering, Faculty of Engineering and Research Center for Environmental and Hazardous Substance Management, Khon Kaen University, Khon Kaen, Thailand
| | - Prasit Thongbai
- Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
| | - Jindarat Ekprasert
- Department of Microbiology, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
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Irshad MA, Sattar S, Nawaz R, Al-Hussain SA, Rizwan M, Bukhari A, Waseem M, Irfan A, Inam A, Zaki MEA. Enhancing chromium removal and recovery from industrial wastewater using sustainable and efficient nanomaterial: A review. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 263:115231. [PMID: 37429088 DOI: 10.1016/j.ecoenv.2023.115231] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 06/20/2023] [Accepted: 07/03/2023] [Indexed: 07/12/2023]
Abstract
Water contamination can be detrimental to the human health due to higher concentration of carcinogenic heavy metals such as chromium (Cr) in the wastewater. Many traditional methods are being employed in wastewater treatment plants for Cr removal to control the environmental impacts. Such methods include ion exchange, coagulation, membrane filtration, and chemical precipitation and microbial degradation. Recent advances in materials science and green chemistry have led to the development of nanomaterial that possess high specific surface areas and multiple functions, making them suitable for removing metals such as Cr from wastewater. Literature shows that the most efficient, effective, clean, and long-lasting approach for removing heavy metals from wastewater involves adsorbing heavy metals onto the surface of nanomaterial. This review assesses the removal methods of Cr from wastewater, advantages and disadvantages of using nanomaterial to remove Cr from wastewater and potential negative impacts on human health. The latest trends and developments in Cr removal strategies using nanomaterial adsorption are also explored in the present review.
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Affiliation(s)
- Muhammad Atif Irshad
- Department of Environmental Sciences, The University of Lahore, Lahore 54000, Pakistan
| | - Sana Sattar
- Department of Environmental Sciences, The University of Lahore, Lahore 54000, Pakistan
| | - Rab Nawaz
- Department of Environmental Sciences, The University of Lahore, Lahore 54000, Pakistan; Research and Knowledge Transfer, INTI International University, Putra Nilai 71800, Malaysia
| | - Sami A Al-Hussain
- Department of Chemistry, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11623, Saudi Arabia
| | - Muhammad Rizwan
- Department of Environmental Sciences and Engineering, Government College University Faisalabad, Faisalabad 38000, Pakistan
| | - Attaullah Bukhari
- Department of Chemistry, The University of Lahore, Lahore 54000, Pakistan
| | - Muhammad Waseem
- Department of Environmental Sciences and Engineering, Government College University Faisalabad, Faisalabad 38000, Pakistan
| | - Ali Irfan
- Department of Chemistry, Government College University Faisalabad, Faisalabad 38000, Pakistan.
| | - Aqil Inam
- Institute of Metallurgy and Materials Engineering, University of the Punjab, Lahore 54000, Pakistan
| | - Magdi E A Zaki
- Department of Chemistry, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11623, Saudi Arabia.
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Synthesis and Surface Modification of Iron Oxide Nanoparticles for the Extraction of Cadmium Ions in Food and Water Samples: A Chemometric Study. SEPARATIONS 2023. [DOI: 10.3390/separations10020124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Abstract
In this project, a prompt, efficient, and effective method for Cd2+ ions extraction from different food and water samples using magnetic dispersion-based solid phase extraction by functionalized iron oxide nanoparticles was proposed. Iron oxide nanoparticles were synthesized through the co-precipitation method followed by functionalization with tetraethyl orthosilicate (TEOS) and 3-aminopropyl silane (APTES) to obtain Fe3O4@SiO2@APTES. This composite was characterized through different techniques, including vibrating sample magnetometer, dynamic light scattering, zeta potential, FTIR, SEM, XRD, and BET. Variables studied were pH, temperature, sorbent amount, sonication time, and sample and eluent volume affecting the sorption efficacy of freshly synthesized sorbent. Plackett–Burman design was utilized for the identification of significant factors for microextraction of target analyte, while the central composite design was utilized for the optimization of significant factors. Detection and quantification limits obtained were 0.17 and 0.58 μgL−1, respectively, with an enhancement factor of 83.5. Under optimum conditions, Fe3O4@SiO2@APTES showed good stability even after >80 adsorption/desorption cycles run while maintaining over 96% analyte recoveries. The developed method was validated by assessing certified reference materials and standard addition methodology for Cd2+ detection in real samples. To confirm the precision, repeatability (RSDr) and reproducibility (RSDR) were calculated and found as <3.0 (n = 7) and <7.5 (n = 15), respectively. Furthermore, in accordance with the ISO/IEC 17025 recommendations, the validation was also confirmed through a “bottom-up” approach while considering all possible uncertainties in data.
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Sharma P, Prakash J, Palai T, Kaushal R. Surface functionalization of bamboo leave mediated synthesized SiO 2 nanoparticles: Study of adsorption mechanism, isotherms and enhanced adsorption capacity for removal of Cr (VI) from aqueous solution. ENVIRONMENTAL RESEARCH 2022; 214:113761. [PMID: 35793724 DOI: 10.1016/j.envres.2022.113761] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 06/19/2022] [Accepted: 06/21/2022] [Indexed: 06/15/2023]
Abstract
Green synthesis of nanoparticles (NPs) provides economic and environmental benefits as an alternative to chemical or physical methods. Furthermore, the surface properties of such NPs can be modulated by means of the functionalization with different groups making them suitable for various advanced functional applications including water pollutants removal using adsorption technique. In the present work, an eco-friendly synthesis route for nano-adsorbent SiO2 NPs and subsequent surface modifications for enhanced adsorption capacity in removal of Cr(VI) ions from aqueous solution are reported. The green synthesis of SiO2 NPs was carried out using simple bamboo leaves followed by surface modification with amine (A-SiO2) and carboxylic (C-SiO2) functional groups with aim to study the effect of functionalization on adsorption capacity. These nano-adsorbents were characterized by FTIR, SEM, XPS, BET, and zeta potential. and adsorption of Cr(VI) was studied at varying parameters i.e. NPs mass, contact time, and solution pH. The investigation shows interesting results revealing the importance of interactions between the surface functional groups on SiO2 NPs and Cr(VI) species as well as experimental conditions for the choice of surface modifier to achieve a maximum adsorption capacity. The adsorption mechanism has been studied using Langmuir, Freundlich and Temkin adsorption isotherms. The maximum adsorption capacity has been achieved in the case of A-SiO2 NPs which was found to 174 mg/g and much higher than that of SiO2 and C-SiO2 NPs attributed to the selective adsorption and pH conditions. Additionally, A-SiO2 NPs exhibit excellent recyclability indicating their suitability for promising and long term potential applications. This study provides a novel, simple and cost-effective synthesis/surface engineering technology for producing high performance recyclable nano-adsorbents for adsorptive removal of Cr(VI).
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Affiliation(s)
- Pratibha Sharma
- Department of Chemistry, National Institute of Technology Hamirpur, H.P.-177005, India
| | - Jai Prakash
- Department of Chemistry, National Institute of Technology Hamirpur, H.P.-177005, India.
| | - Tapas Palai
- Department of Chemical Engineering, National Institute of Technology Hamirpur, H.P.-177005, India
| | - Raj Kaushal
- Department of Chemistry, National Institute of Technology Hamirpur, H.P.-177005, India.
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Amino-modified magnetic glucose-based carbon composites for efficient Cr(VI) removal. J Taiwan Inst Chem Eng 2022. [DOI: 10.1016/j.jtice.2022.104419] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Iron nanoparticles to recover a co-contaminated soil with Cr and PCBs. Sci Rep 2022; 12:3541. [PMID: 35241772 PMCID: PMC8894337 DOI: 10.1038/s41598-022-07558-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 02/03/2022] [Indexed: 11/08/2022] Open
Abstract
Little attention has been given to the development of remediation strategies for soils polluted with mixture of pollution (metal(loid)s and organic compounds). The present study evaluates the effectiveness of different types of commercial iron nanoparticles (nanoscale zero valent iron (nZVI), bimetallic nZVI-Pd, and nano-magnetite (nFe3O4)), for the remediation of an industrial soil co-contaminated with Cr and PCBs. Soil samples were mixed with nZVI, nZVI-Pd, or nFe3O4 at doses selected according to their reactivity with PCBs, homogenized, saturated with water and incubated at controlled conditions for 15, 45 and 70 days. For each sampling time, PCBs and chromium were analyzed in aqueous and soil fractions. Cr(VI) and Cr leachability (TCLP test) were determined in the soil samples. The treatment with the three types of iron nanoparticles showed significant reduction in Cr concentration in aqueous extracts at the three sampling times (> 98%), compared to the control samples. The leachability of Cr in treated soil samples also decreased and was stable throughout the experiment. Results suggested that nZVI and nZVI-Pd immobilized Cr through adsorption of Cr(VI) on the shell and reduction to Cr(III). The mechanism of interaction of nFe3O4 and Cr(VI) included adsorption and reduction although its reducing character was lower than those of ZVI nanoparticles. PCBs significantly decreased in soil samples (up to 68%), after 15 days of treatment with the three types of nanoparticles. However, nFe3O4 evidenced reversible adsorption of PCBs after 45 days. In general, nZVI-Pd reduced PCB concentration in soil faster than nZVI. Control soils showed a similar reduction in PCBs concentration as those obtained with nZVI and nZVI-Pd after a longer time (45 days). This is likely due to natural bioremediation, although it was not effective for Cr remediation. Results suggest that the addition of nZVI or nZVI-Pd and pseudo-anaerobic conditions could be used for the recovery of soil co-contaminated with Cr and PCBs.
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Efficient removal of Cr(VI) using partially oxidized FeS under visible light. RESEARCH ON CHEMICAL INTERMEDIATES 2022. [DOI: 10.1007/s11164-022-04657-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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8
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Nanotheranostic agents for neurodegenerative diseases. Emerg Top Life Sci 2021; 4:645-675. [PMID: 33320185 DOI: 10.1042/etls20190141] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 11/16/2020] [Accepted: 11/19/2020] [Indexed: 02/07/2023]
Abstract
Neurodegenerative diseases (NDDs), including Alzheimer's disease (AD) and Parkinson's disease (PD), affect the ageing population worldwide and while severely impairing the quality of life of millions, they also cause a massive economic burden to countries with progressively ageing populations. Parallel with the search for biomarkers for early detection and prediction, the pursuit for therapeutic approaches has become growingly intensive in recent years. Various prospective therapeutic approaches have been explored with an emphasis on early prevention and protection, including, but not limited to, gene therapy, stem cell therapy, immunotherapy and radiotherapy. Many pharmacological interventions have proved to be promising novel avenues, but successful applications are often hampered by the poor delivery of the therapeutics across the blood-brain-barrier (BBB). To overcome this challenge, nanoparticle (NP)-mediated drug delivery has been considered as a promising option, as NP-based drug delivery systems can be functionalized to target specific cell surface receptors and to achieve controlled and long-term release of therapeutics to the target tissue. The usefulness of NPs for loading and delivering of drugs has been extensively studied in the context of NDDs, and their biological efficacy has been demonstrated in numerous preclinical animal models. Efforts have also been made towards the development of NPs which can be used for targeting the BBB and various cell types in the brain. The main focus of this review is to briefly discuss the advantages of functionalized NPs as promising theranostic agents for the diagnosis and therapy of NDDs. We also summarize the results of diverse studies that specifically investigated the usage of different NPs for the treatment of NDDs, with a specific emphasis on AD and PD, and the associated pathophysiological changes. Finally, we offer perspectives on the existing challenges of using NPs as theranostic agents and possible futuristic approaches to improve them.
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Wu H, Chen J, Xu L, Guo X, Fang P, Du K, Shen C, Sheng G. Decorating nanoscale FeS onto metal-organic framework for the decontamination performance and mechanism of Cr(VI) and Se(IV). Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2021.126887] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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10
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Yi Y, Wang X, Ma J, Ning P. Fe(III) modified Egeria najas driven-biochar for highly improved reduction and adsorption performance of Cr(VI). POWDER TECHNOL 2021. [DOI: 10.1016/j.powtec.2021.04.066] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Zhu Y, He X, Xu J, Fu Z, Wu S, Ni J, Hu B. Insight into efficient removal of Cr(VI) by magnetite immobilized with Lysinibacillus sp. JLT12: Mechanism and performance. CHEMOSPHERE 2021; 262:127901. [PMID: 32805660 DOI: 10.1016/j.chemosphere.2020.127901] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 06/28/2020] [Accepted: 08/01/2020] [Indexed: 06/11/2023]
Abstract
In this work, Lysinibacillus sp. JLT12 was used to remove the Cr(VI)-induced passive layer on the magnetite. Mechanism study via dynamic kinetics, X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy analyses revealed that Lysinibacillus sp. JLT12 could remove the passive layer (lepidocrocite and goethite) to facilitate the further Cr(VI) reduction by magnetite. For large-scale applications, porous ceramsite (PC) was prepared with magnetite, kaolin, and fallen leaves. Lysinibacillus sp. was then immobilized on the holes in PC. Slow-released nutrients were added to immobilized porous ceramsite (IM-PC) at a ratio of 1.5:10 (g/g) to supply carbon, nitrogen, and phosphorus to Lysinibacillus sp. JLT12 with low secondary pollution. The performance of IM-PC was evaluated via a column experiment. The results indicate that, in the presence of Lysinibacillus, the break-through time and maximum adsorption ability of IM-PC were 11.67 h and 121.47 mg/g, respectively. These values are higher than those of PC. Additionally, break-through curves detected at 5, 10, and 15 days demonstrated that the usage life of IM-PC was significantly longer than that of PC.
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Affiliation(s)
- Yuling Zhu
- School of Life Science, Shaoxing University, Huancheng West Road 508, Shaoxing, 312000, PR China
| | - Xiaoyun He
- School of Life Science, Shaoxing University, Huancheng West Road 508, Shaoxing, 312000, PR China; School of Civil Engineering, Shaoxing University, Huancheng West Road 508, Shaoxing, 312000, PR China
| | - Jiali Xu
- School of Civil Engineering, Shaoxing University, Huancheng West Road 508, Shaoxing, 312000, PR China
| | - Zheng Fu
- School of Life Science, Shaoxing University, Huancheng West Road 508, Shaoxing, 312000, PR China
| | - Siying Wu
- School of Civil Engineering, Shaoxing University, Huancheng West Road 508, Shaoxing, 312000, PR China
| | - Jian Ni
- School of Life Science, Shaoxing University, Huancheng West Road 508, Shaoxing, 312000, PR China
| | - Baowei Hu
- School of Life Science, Shaoxing University, Huancheng West Road 508, Shaoxing, 312000, PR China.
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PFEIFER A, ŠKERGET M. A review: a comparison of different adsorbents for removal of Cr (VI), Cd (II) and Ni (II). Turk J Chem 2020; 44:859-883. [PMID: 33488199 PMCID: PMC7751917 DOI: 10.3906/kim-2002-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 06/07/2020] [Indexed: 01/19/2023] Open
Abstract
A review of the studies dealing with the removal of chromium, cadmium, and nickel ions with different adsorbents published in the literature between 2014 and 2018 is given in tabular form, along with the adsorption conditions, adsorption isotherm, and kinetic models applied by the authors to model the experimental data and adsorption capacities. The review focuses on the efficiency of ion removal.
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Affiliation(s)
- Anja PFEIFER
- Faculty of Chemistry and Chemical Engineering, University of Maribor, MariborSlovenia
| | - Mojca ŠKERGET
- Faculty of Chemistry and Chemical Engineering, University of Maribor, MariborSlovenia
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Ajmal Z, Usman M, Anastopoulos I, Qadeer A, Zhu R, Wakeel A, Dong R. Use of nano-/micro-magnetite for abatement of cadmium and lead contamination. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 264:110477. [PMID: 32250903 DOI: 10.1016/j.jenvman.2020.110477] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 02/27/2020] [Accepted: 03/22/2020] [Indexed: 06/11/2023]
Abstract
Structural variations of a mineral dictate its adsorption capacity which affects the mobility and toxicity of contaminants in natural and engineered systems. Present batch study evaluates the adsorption of lead (Pb) and cadmium (Cd) onto three magnetites having nanometric (M1-30 nm and M2-60 nm) and micrometric particle sizes (M3-1.5 μm). Obtained data revealed that particle size of tested magnetites strongly affected the extent and kinetics of metal adsorption and desorption. Observed order of adsorption efficiency was M1 > M2 > M3 with optimum monolayer adsorption of 408.14, 331.40, 178.47 mg/g (for Pb) and 228.05, 170.86, 83.49 mg/g (for Cd), respectively. Adsorption data were well fitted to the Freundlich (R2 = 0.99), Langmuir (R2 = 0.99) and pseudo-first order models (R2 = 0.98). Electrostatic attraction and surface precipitation interaction via external mass transfer between bulk liquid-solid interfaces were the potential adsorption pathways. Pb showed higher affinity than Cd in multi-metal system. Desorption efficiency was higher in acidic environment (92%) than in distilled water (44%). Moreover, regenerated magnetite samples retained good adsorption capacity for six cycles. As soils are characterized by large variability of iron minerals, these findings have important implications regarding the transport and immobilization of contaminants particularly in the management of contaminated soils.
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Affiliation(s)
- Zeeshan Ajmal
- Institute of Soil and Environmental Sciences, University of Agriculture, Faisalabad, 38040, Pakistan; MoA Key Laboratory for Clean Production and Utilization of Renewable Energy, MoST National Center for International Research of BioEnergy Science and Technology, College of Engineering, China Agricultural University, 100083, Beijing, China
| | - Muhammad Usman
- Institute of Soil and Environmental Sciences, University of Agriculture, Faisalabad, 38040, Pakistan; PEIE Research Chair of Public Establishment for Industrial Estates and Free Zones, Center for Environmental Studies and Research, Sultan Qaboos University, Al-Khoud 123, Muscat, Oman.
| | - Ioannis Anastopoulos
- Radioanalytical and Environmental Chemistry Group, Department of Chemistry, University of Cyprus, P.O. Box 20537, Nicosia, CY-1678, Cyprus
| | - Abdul Qadeer
- Institute of Soil and Environmental Sciences, University of Agriculture, Faisalabad, 38040, Pakistan; Key Laboratory of Geographic Information Science of the Ministry of Education, School of Geographical Sciences, East China Normal University, Shanghai, 200241, China
| | - Runliang Zhu
- Guangzhou Institutes of Geochemistry, Chinese Academy of Sciences, 510640, Guangzhou, China
| | - Abdul Wakeel
- Institute of Soil and Environmental Sciences, University of Agriculture, Faisalabad, 38040, Pakistan
| | - Renjie Dong
- MoA Key Laboratory for Clean Production and Utilization of Renewable Energy, MoST National Center for International Research of BioEnergy Science and Technology, College of Engineering, China Agricultural University, 100083, Beijing, China
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Dzieniszewska A, Kyziol-Komosinska J, Pająk M. Adsorption and bonding strength of chromium species by ferrihydrite from acidic aqueous solutions. PeerJ 2020; 8:e9324. [PMID: 32566408 PMCID: PMC7293855 DOI: 10.7717/peerj.9324] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 05/18/2020] [Indexed: 11/22/2022] Open
Abstract
The adsorption behavior of Cr(III) and Cr(VI) ions onto laboratory-synthesized 2-line ferrihydrite was investigated under a batch method as a function of initial chromium concentration (0.1-1000 mg L-1) and pH (3.0 and 5.0). Moreover, the effect of the type of anion (chloride and sulfate) on Cr(III) adsorption was studied. The affinity of Cr(III) ions for the ferrihydrite surface depended on both the type of anion and pH of the solution and the maximum adsorption capacities decreased as follows: q (SO4 2-, pH 5.0) > q (SO4 2-, pH 3.0) > q (Cl-, pH 5.0) > q (Cl-, pH 3.0), and were found to be 86.06 mg g-1, 83.59 mg g-1, 61.51 mg g-1 and 40.67 mg g-1, respectively. Cr(VI) ions were bound to ferrihydrite in higher amounts then Cr(III) ions and the maximum adsorption capacity increased as the pH of the solution decreased and was 53.14 mg g-1 at pH 5.0 and 83.73 mg g-1 at pH 3.0. The adsorption process of Cr species was pH dependent, and the ions were bound to the surface of ferrihydrite by surface complexation. The Sips isotherm was the best-fit model to the results obtained from among the four isotherm models used, i.e., Freundlich, Langmuir, Dubinin-Radushkevich and Sips, indicating different adsorption centers participate in Cr uptake. In order to assess the bonding strength of the adsorbed chromium ions the modified BCR procedure, dedicated to the samples with a high iron content, was used. The results of the sequential extraction showed that Cr(III) ions were bound mainly in the immobile residual fraction and Cr(VI) ions were bound in the reducible fraction. The presence of Fe (oxyhydr)oxides in soil and sediments increases their adsorption capacity for Cr, in particular for hexavalent Cr in an acid environment due to their properties (high pHPZC).
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Affiliation(s)
| | | | - Magdalena Pająk
- Institute of Environmental Engineering, Polish Academy of Sciences, Zabrze, Poland
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Liu Y, Jin X, Chen Z. The formation of iron nanoparticles by Eucalyptus leaf extract and used to remove Cr(VI). THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 627:470-479. [PMID: 29426170 DOI: 10.1016/j.scitotenv.2018.01.241] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Revised: 01/21/2018] [Accepted: 01/24/2018] [Indexed: 06/08/2023]
Abstract
The advantages of green synthesized iron nanoparticles by plant extracts include simplicity, high efficiency and sustainability. However, there are limitations in our understanding of the formation of Fe NPs. In this report, the synthesized iron nanoparticles by eucalyptus leaf extract (Fe NPs) showed that Cr(VI) removal efficiency reached approximately 100% at volume ratio of leaf extract and iron(III) solution of 2:1 and pH 4. In addition, the morphology, surface and compositions of Fe NPs were characterized by various techniques. The diameter distribution of 95 ± 5 nm with a capping layer was observed, containing polyphenols and aliphatic acids confirmed by FTIR and XRD. XPS indicated that Fe NPs contained iron oxides, as well as a layer covering on Fe NPs created by biomolecules from eucalyptus leaf extract. Furthermore, the biomolecules identified by GC-MS indicated that alcohol phenols and alkylaldehyde acted as reducing agents, while alcohol acids, alkanols, phytols, acetate and aromatic ketones acted as capping agents. It can be concluded that aldehydes, phenols and alcoholic compounds played dominant roles during the synthesis of Fe NPs. Finally, the mechanism for the formation of Fe NPs was proposed, including both that of Fe NPs and capped Fe NPs.
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Affiliation(s)
- Yong Liu
- Fujian Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province, China
| | - Xiaoying Jin
- Fujian Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province, China
| | - Zuliang Chen
- Fujian Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province, China..
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Efficient removal of iodine and chromium as anionic species from radioactive liquid waste using prepared iron oxide nanofibers. J Radioanal Nucl Chem 2018. [DOI: 10.1007/s10967-018-5938-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Wei X, Wu Z, Wu Z, Ye BC. Adsorption behaviors of atrazine and Cr(III) onto different activated carbons in single and co-solute systems. POWDER TECHNOL 2018. [DOI: 10.1016/j.powtec.2018.01.060] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Usman M, Byrne JM, Chaudhary A, Orsetti S, Hanna K, Ruby C, Kappler A, Haderlein SB. Magnetite and Green Rust: Synthesis, Properties, and Environmental Applications of Mixed-Valent Iron Minerals. Chem Rev 2018; 118:3251-3304. [PMID: 29465223 DOI: 10.1021/acs.chemrev.7b00224] [Citation(s) in RCA: 185] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Mixed-valent iron [Fe(II)-Fe(III)] minerals such as magnetite and green rust have received a significant amount of attention over recent decades, especially in the environmental sciences. These mineral phases are intrinsic and essential parts of biogeochemical cycling of metals and organic carbon and play an important role regarding the mobility, toxicity, and redox transformation of organic and inorganic pollutants. The formation pathways, mineral properties, and applications of magnetite and green rust are currently active areas of research in geochemistry, environmental mineralogy, geomicrobiology, material sciences, environmental engineering, and environmental remediation. These aspects ultimately dictate the reactivity of magnetite and green rust in the environment, which has important consequences for the application of these mineral phases, for example in remediation strategies. In this review we discuss the properties, occurrence, formation by biotic as well as abiotic pathways, characterization techniques, and environmental applications of magnetite and green rust in the environment. The aim is to present a detailed overview of the key aspects related to these mineral phases which can be used as an important resource for researchers working in a diverse range of fields dealing with mixed-valent iron minerals.
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Affiliation(s)
- M Usman
- Environmental Mineralogy, Center for Applied Geosciences , University of Tübingen , 72074 Tübingen , Germany.,Institute of Soil and Environmental Sciences , University of Agriculture , Faisalabad 38040 , Pakistan
| | - J M Byrne
- Geomicrobiology, Center for Applied Geosciences , University of Tübingen , 72074 Tübingen , Germany
| | - A Chaudhary
- Environmental Mineralogy, Center for Applied Geosciences , University of Tübingen , 72074 Tübingen , Germany.,Department of Environmental Science and Engineering , Government College University Faisalabad 38000 , Pakistan
| | - S Orsetti
- Environmental Mineralogy, Center for Applied Geosciences , University of Tübingen , 72074 Tübingen , Germany
| | - K Hanna
- Univ Rennes, École Nationale Supérieure de Chimie de Rennes , CNRS, ISCR - UMR6226 , F-35000 Rennes , France
| | - C Ruby
- Laboratoire de Chimie Physique et Microbiologie pour l'Environnement , UMR 7564 CNRS-Université de Lorraine , 54600 Villers-Lès-Nancy , France
| | - A Kappler
- Geomicrobiology, Center for Applied Geosciences , University of Tübingen , 72074 Tübingen , Germany
| | - S B Haderlein
- Environmental Mineralogy, Center for Applied Geosciences , University of Tübingen , 72074 Tübingen , Germany
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Mahmoudi E, Behnajady MA. Synthesis of Fe3O4@NiO core-shell nanocomposite by the precipitation method and investigation of Cr(VI) adsorption efficiency. Colloids Surf A Physicochem Eng Asp 2018. [DOI: 10.1016/j.colsurfa.2017.11.020] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Bian L, Li YJ, Li J, Nie JN, Dong FQ, Song MX, Wang LS, Dong HL, Li HL, Nie XQ, Zhang XY, Li XX, Xie L. Photovoltage response of (XZn)Fe 2O 4-BiFeO 3 (X=Mg, Mn or Ni) interfaces for highly selective Cr 3+, Cd 2+, Co 2+ and Pb 2+ ions detection. JOURNAL OF HAZARDOUS MATERIALS 2017; 336:174-187. [PMID: 28494305 DOI: 10.1016/j.jhazmat.2017.04.071] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 04/13/2017] [Accepted: 04/28/2017] [Indexed: 06/07/2023]
Abstract
High-photostability fluorescent (XZn)Fe2O4 (X=Mg, Mn or Ni) embedded in BiFeO3 spinel-perovskite nanocomposites were successfully fabricated via a novel bio-induced phase transfer method using shewanella oneidensis MR-1. These nanocomposites have the near-infrared fluorescence response (XZn or Fe)-O-O-(Bi) interfaces (785/832nm), and the (XZn)Fe2O4/BiFeO3 lattices with high/low potentials (572.15-808.77meV/206.43-548.1meV). Our results suggest that heavy metal ion (Cr3+, Cd2+, Co2+ and Pb2+) d↓ orbitals hybridize with the paired-spin X-Zn-Fe d↓-d↓-d↑↓ orbitals to decrease the average polarization angles (-29.78 to 44.71°), qualitatively enhancing the photovoltage response selective potentials (39.57-487.84meV). The fluorescent kinetic analysis shows that both first-order and second-order equilibrium adsorption isotherms are in line and meet the Langmuir and Freundlich modes. Highly selective fluorescence detection of Co2+, Cr3+ and Cd2+ can be achieved using Fe3O4-BiFeO3 (Langmuir mode), (MgZn)Fe2O4-BiFeO3 and (MnZn)Fe2O4-BiFeO3 (Freundlich mode), respectively. Where the corresponding max adsorption capacities (qmax) are 1.5-1.94, 35.65 and 43.7 multiple, respectively, being more competitive than that of other heavy metal ions. The present bio-synthesized method might be relevant for high-photostability fluorescent spinel-perovskite nanocomposites, for design of heavy metal ion sensors.
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Affiliation(s)
- Liang Bian
- Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, South West University of Science and Technology, Mianyang 621010, Sichuan, China; Institute of Gem and Material Technology, Hebei GEO University, Shijiazhuang 050000, Hebei, China; Key Laboratory of Functional Materials and Devices under Special Environments, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China.
| | - Yu-Jin Li
- Key Laboratory of Functional Materials and Devices under Special Environments, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China
| | - Jing Li
- Key Laboratory of Functional Materials and Devices under Special Environments, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China
| | - Jia-Nan Nie
- Key Laboratory of Functional Materials and Devices under Special Environments, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China
| | - Fa-Qin Dong
- Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, South West University of Science and Technology, Mianyang 621010, Sichuan, China
| | - Mian-Xin Song
- Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, South West University of Science and Technology, Mianyang 621010, Sichuan, China
| | - Li-Sheng Wang
- Institute of Gem and Material Technology, Hebei GEO University, Shijiazhuang 050000, Hebei, China
| | - Hai-Liang Dong
- Department of Geology and Environmental Earth Science, Miami University, Oxford 45056, USA
| | - Hai-Long Li
- Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, South West University of Science and Technology, Mianyang 621010, Sichuan, China; Key Laboratory of Functional Materials and Devices under Special Environments, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China
| | - Xiao-Qin Nie
- Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, South West University of Science and Technology, Mianyang 621010, Sichuan, China
| | - Xiao-Yan Zhang
- Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, South West University of Science and Technology, Mianyang 621010, Sichuan, China; Key Laboratory of Functional Materials and Devices under Special Environments, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China
| | - Xin-Xi Li
- Institute of Nuclear Physics and Chemistry, CAEP, Mianyang 621900, Sichuan, China
| | - Lei Xie
- Institute of Nuclear Physics and Chemistry, CAEP, Mianyang 621900, Sichuan, China
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Cruz DRS, Santos BTJ, Cunha GC, Romão LPC. Green synthesis of a magnetic hybrid adsorbent (CoFe 2O 4/NOM): Removal of chromium from industrial effluent and evaluation of the catalytic potential of recovered chromium ions. JOURNAL OF HAZARDOUS MATERIALS 2017; 334:76-85. [PMID: 28402897 DOI: 10.1016/j.jhazmat.2017.03.062] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 03/13/2017] [Accepted: 03/29/2017] [Indexed: 06/07/2023]
Abstract
This work describes the removal of chromium ions from industrial effluent using a hybrid magnetic adsorbent, CoFe2O4/NOM, synthesized using water rich in natural organic matter. The hybrid obtained at ambient temperature (HbAmb) was calcined at 200, 400, and 800°C for 2h, and formation of the cobalt ferrite phase was confirmed by XRD, which indicated the presence of NOM in the structure of the material. Removal tests showed that HbAmb provided efficient removal of chromium at the natural pH of the effluent, while the other materials were effective at pH 6. Evaluation of the kinetics showed excellent performance of the process, with 70-87% removal in 20min, which provided a high degree of flexibility. The hybrid showed high removal during five reuse cycles, ranging from 96% in the first cycle to 82% in the final. The matrices containing the saturated adsorbent (HbAmb_Sat) and recovered chromium ions (CrD) showed high performance in the catalytic reduction of 4-nitrophenol, with conversion rates of 99.9% in short periods of time, as well as excellent potential for reuse in three cycles. The results demonstrated that the production of a technological material and its use for remediation could be achieved in an ecologically sustainable manner.
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Affiliation(s)
- Daiane R S Cruz
- Chemistry Department, Federal University of Sergipe (UFS), 49100-000 São Cristóvão, SE, Brazil
| | - Bruna T J Santos
- Chemistry Department, Federal University of Sergipe (UFS), 49100-000 São Cristóvão, SE, Brazil
| | - Graziele C Cunha
- Chemistry Department, Federal University of Sergipe (UFS), 49100-000 São Cristóvão, SE, Brazil
| | - Luciane P C Romão
- Chemistry Department, Federal University of Sergipe (UFS), 49100-000 São Cristóvão, SE, Brazil.
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Valle JP, Gonzalez B, Schultz J, Salinas D, Gonzalez DF, Valdes C, Cantu JM, Eubanks TM, Parsons JG. Sorption of Cr(III) and Cr(VI) to K 2Mn 4O 9 nanomaterial a Study of the effect of pH, time, temperature and interferences. Microchem J 2017; 133:614-621. [PMID: 29081543 DOI: 10.1016/j.microc.2017.04.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A Rancieite type material (K2Mn4O9) nanomaterial was synthesized and tested for the removal of chromium (III) and chromium (VI) from aqueous solutions. The synthesized nanomaterial was characterized using powder XRD and SEM. XRD showed weak diffraction peaks at only at the angles associated with K2Mn4O9. The SEM corroborated that the nanoparticles were present; however, the nanoparticles were clustered into larger aggregates. Batch studies were performed to determine the optimum pH, capacity, time dependency, interferences, and the thermodynamics of the binding. The optimum pH for the binding of Cr(III) and Cr(VI) were determined to be pH 5 and pH 2, respectively. Isotherm studies were performed at temperatures of 4 , 25 , and 45 for Cr(III) and Cr(VI) and showed binding capacities of 21.7 mg/g, 36.5 mg/g, 41.8 mg/g for Cr(III). The Cr(VI) binding capacities were 4.22 mg/g, 4.08 mg/g, and 3.25 mg/g at the respective temperatures. The thermodynamic studies showed that the binding processes for the reactions were spontaneous and endothermic, with a ΔH was 17.54 kJ/mol for Cr(III) and 6.05 kJ/mol for Cr(VI). The of sorption for Cr(III) were determined to be -3.88 kJ/mol, -5.83 kJ/mol and -7.03 kJ/mol at the aforementioned temperatures. The ΔG values for the Cr(VI) sorption were determined to be -4.89 kJ/mol, -5.64 kJ/mol, and -6.05 kJ/mol. In addition, the ΔS values for Cr(III) and Cr(VI) were determined to be 77.92 J/mol and 39.49 J/mol, respectively. The thermodynamics indicate that the binding of Cr(III) and Cr(VI) is spontaneous and endothermic.
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Affiliation(s)
- J P Valle
- Department of Chemistry University of Texas Rio Grande Valley, 1201 W University Dr. Edinburg, TX 78539
| | - B Gonzalez
- Department of Chemistry University of Texas Rio Grande Valley, 1201 W University Dr. Edinburg, TX 78539
| | - J Schultz
- Department of Chemistry University of Texas Rio Grande Valley, 1201 W University Dr. Edinburg, TX 78539
| | - D Salinas
- Department of Chemistry University of Texas Rio Grande Valley, 1201 W University Dr. Edinburg, TX 78539
| | - D F Gonzalez
- Department of Chemistry University of Texas Rio Grande Valley, 1201 W University Dr. Edinburg, TX 78539
| | - C Valdes
- Department of Chemistry University of Texas Rio Grande Valley, 1201 W University Dr. Edinburg, TX 78539
| | - J M Cantu
- Department of Chemistry University of Texas Rio Grande Valley, 1201 W University Dr. Edinburg, TX 78539
| | - T M Eubanks
- Department of Chemistry University of Texas Rio Grande Valley, 1201 W University Dr. Edinburg, TX 78539
| | - J G Parsons
- Department of Chemistry University of Texas Rio Grande Valley, 1201 W University Dr. Edinburg, TX 78539
- School of Earth, Environmental, and Marine Sciences University of Texas Rio Grande Valley, 1201 W University Dr. Edinburg, TX 78539
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Abstract
The adsorption of Cr(III) or Cr(VI) in the absence and presence of Cu(II) onto kaolin was investigated under pH 2.0–7.0. Results indicated that the adsorption rate was not necessarily proportional to the adsorption capacity. The solutions’ pH values played a key role in kaolin zeta potential(ζ), especially the hydrolysis behavior and saturation index of heavy metal ions. In the presence of Cu(II),qmixCr(III)reached the maximum adsorption capacity of 0.73 mg·g−1at pH 6.0, while the maximum adsorption capacity for the mixed Cr(VI) and Cu(II) system (qmixCr(VI)) was observed at pH 2.0 (0.38 mg·g−1). Comparing the adsorption behaviors and mechanisms, we found that kaolin prefers to adsorb hydrolyzed products of Cr(III) instead of Cr3+ion, while adsorption sites of kaolin surface were occupied primarily by Cu(II) through surface complexation, leading to Cu(II) inhibited Cr(VI) adsorption. Moreover, Cr(III) and Cr(VI) removal efficiency had a positive correlation with distribution coefficientKd. Cr(III) and Cr(VI) removal efficiency had a positive correlation with distribution coefficientKdand that of adsorption affinities of Cr(III) or Cr(VI) on kaolin was found to beKdCr(III) <KdCr(III)-Cu(II) andKdCr(VI) >KdCr(VI)-Cu(II).
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Meena AH, Arai Y. Effects of common groundwater ions on chromate removal by magnetite: importance of chromate adsorption. GEOCHEMICAL TRANSACTIONS 2016; 17:1. [PMID: 27134569 PMCID: PMC4850710 DOI: 10.1186/s12932-016-0033-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 04/15/2016] [Indexed: 05/11/2023]
Abstract
BACKGROUND Reductive precipitation of hexavalent chromium (Cr(VI)) with magnetite is a well-known Cr(VI) remediation method to improve water quality. The rapid (<a few hr) reduction of soluble Cr(VI) to insoluble Cr(III) species by Fe(II) in magnetite has been the primary focus of the Cr(VI) removal process in the past. However, the contribution of simultaneous Cr(VI) adsorption processes in aged magnetite has been largely ignored, leaving uncertainties in evaluating the application of in situ Cr remediation technologies for aqueous systems. In this study, effects of common groundwater ions (i.e., nitrate and sulfate) on Cr(VI) sorption to magnetite were investigated using batch geochemical experiments in conjunction with X-ray absorption spectroscopy. RESULTS In both nitrate and sulfate electrolytes, batch sorption experiments showed that Cr(VI) sorption decreases with increasing pH from 4 to 8. In this pH range, Cr(VI) sorption decreased with increasing ionic strength of sulfate from 0.01 to 0.1 M whereas nitrate concentrations did not alter the Cr(VI) sorption behavior. This indicates the background electrolyte specific Cr(VI) sorption process in magnetite. Under the same ionic strength, Cr(VI) removal in sulfate containing solutions was greater than that in nitrate solutions. This is because the oxidation of Fe(II) by nitrate is more thermodynamically favorable than by sulfate, leaving less reduction capacity of magnetite to reduce Cr(VI) in the nitrate media. X-ray absorption spectroscopy analysis supports the macroscopic evidence that more than 75 % of total Cr on the magnetite surfaces was adsorbed Cr(VI) species after 48 h. CONCLUSION This experimental geochemical study showed that the adsorption process of Cr(VI) anions was as important as the reductive precipitation of Cr(III) in describing the removal of Cr(VI) by magnetite, and these interfacial adsorption processes could be impacted by common groundwater ions like sulfate and nitrate. The results of this study highlight new information about the large quantity of adsorbed Cr(VI) surface complexes at the magnetite-water interface. It has implications for predicting the long-term stability of Cr at the magnetite-water interface.Graphical abstractEffects of background anions (sulfate and nitrate) on the Cr(VI) surface coverage at the magnetite-water interface at pH 4 and 9.
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Affiliation(s)
- Amanda H. Meena
- />School of Agricultural, Forest and Environmental Sciences, Clemson University, Clemson, SC 29634 USA
| | - Yuji Arai
- />Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
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