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Liu A, Fu J, Liu Z, Shi S, Zhang WX. Interfacial reactions and speciation identification during arsenic treated with nanoscale zerovalent iron (nZVI) in water: A review. WATER RESEARCH 2025; 283:123829. [PMID: 40414096 DOI: 10.1016/j.watres.2025.123829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2025] [Revised: 05/10/2025] [Accepted: 05/12/2025] [Indexed: 05/27/2025]
Abstract
This perspective briefly summarized the progress of inorganic arsenic (As) treated with nanoscale zerovalent iron (nZVI) in water over the past two decades. The intrinsic interfacial reaction between As and nZVI encompassed multiple effects, such as complexation, oxidation, reduction, and co-precipitation, ascribed to core-shell structure of nZVI and environmental behavior of As in water. Surface complexation occurred via ligand exchange of arsenate anions with Fe-OH groups on the iron oxide shell. However, interfacial oxidation of As(III) to As(V) was attributed to form a Fe(III) oxide-Fe(II)-As(III) ternary surface complex under anoxic conditions, as well as generate reactive oxygen species (e.g., H2O2, •OH) from iron reacted with O2 under oxic conditions. Reduction of As(III) to As(0) was followed by subsurface accumulation near the Fe(0) core. Advanced characterization techniques, including high-resolution X-ray photoelectron spectroscopy, in situ X-ray absorption spectroscopy, spherical aberration-corrected scanning transmission electron microscope, and density functional theory combined with quick-scanning extended X-ray absorption fine structure, have unraveled the multi-tiered distributions of As on nZVI at atomic scale. This review highlights critical gaps in understanding As-Fe redox dynamics and advocates for future research to engineer nZVI with tailored surface properties for enhanced As sequestration.
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Affiliation(s)
- Airong Liu
- State Key Laboratory of Water Pollution Control and Green Resource Recycling, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, China.
| | - Jiahui Fu
- State Key Laboratory of Water Pollution Control and Green Resource Recycling, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, China
| | - Zhaoli Liu
- State Key Laboratory of Water Pollution Control and Green Resource Recycling, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, China
| | - Shuangjia Shi
- State Key Laboratory of Water Pollution Control and Green Resource Recycling, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, China
| | - Wei-Xian Zhang
- State Key Laboratory of Water Pollution Control and Green Resource Recycling, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, China.
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Chen L, Liu Z, Hu Z, Wang B, Bai Y, Song Y, Che H, Zhang X, Dai H, Wang X. Multifunctional Sites for Enhanced Adsorption of Arsenic Using Sulfydryl-Modified Biochar/MgFe-Layered Double Hydroxides. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2025; 41:10768-10781. [PMID: 40268879 DOI: 10.1021/acs.langmuir.4c04498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2025]
Abstract
Arsenic contamination in water poses a significant threat to the environment and human health due to the high toxicity of arsenic. Therefore, the development of functionalized materials with an enhanced adsorption capacity for arsenic remains a key research focus in water purification. In this study, straw powder was hydrothermally pretreated and subsequently pyrolyzed with zinc chloride at 700 °C to produce hydrothermal biochar with tailored pores. The hydrothermal biochar was then modified with sulfhydryl groups, and Sulfhydryl-Modified Biochar/MgFe-Layered Double Hydroxides (SH@HB/MgFe-LDH) composites were synthesized using the coprecipitation method. By utilizing HB with a high surface area, a composite material with a high specific surface area of 479.3677 m2/g was prepared. The experimental results indicated that the SH@HB/MgFe-LDH composites exhibited excellent arsenic adsorption performance across a wide pH range, achieving an arsenic adsorption capacity as high as 388.01 mg/g. The adsorption process and mechanism of the SH@HB/MgFe-LDH composites were investigated through adsorption kinetics, adsorption isotherms, thermodynamic analysis, and X-ray photoelectron spectroscopy. Additionally, recycling studies demonstrated that the composites maintained stable performance over three reuse cycles, showing good potential for practical applications. Overall, the SH@HB/MgFe-LDH composites offer an effective solution for arsenic pollution control in water while promoting the high-value utilization of agricultural and forestry waste.
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Affiliation(s)
- Long Chen
- College of Science, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Zhechen Liu
- College of Material Science and Art Design, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Zichu Hu
- College of Material Science and Art Design, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Boyun Wang
- College of Science, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Yu Bai
- College of Science, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Yaru Song
- College of Science, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Hengjun Che
- College of Science, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Xiaotao Zhang
- College of Science, Inner Mongolia Agricultural University, Hohhot 010018, China
- Inner Mongolia Key Laboratory of Sandy Shrubs Fibrosis and Energy Development and Utlization, Hohhot 010018, China
- Key Laboratory of Agricultural Ecological Security and Green Development at Universities of Inner Mongolia Autonomous, Hohhot 010018, China
| | - Hongguang Dai
- College of Science, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Ximing Wang
- College of Material Science and Art Design, Inner Mongolia Agricultural University, Hohhot 010018, China
- Inner Mongolia Key Laboratory of Sandy Shrubs Fibrosis and Energy Development and Utlization, Hohhot 010018, China
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Sun Y, Liang S, Li P. Factors Influencing Removal of Trichloroethylene in a Zero-Valent Iron Fenton System. NANOMATERIALS (BASEL, SWITZERLAND) 2025; 15:558. [PMID: 40214601 PMCID: PMC11990697 DOI: 10.3390/nano15070558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2025] [Revised: 03/28/2025] [Accepted: 03/29/2025] [Indexed: 04/14/2025]
Abstract
Trichloroethylene (TCE), a volatile organic compound commonly used as a solvent, is frequently detected in contaminated groundwater. In the zero-valent iron (ZVI) Fenton process, TCE can be eventually dechlorinated into non-toxic products, which is mainly caused by hydroxyl radicals derived from H2O2. However, some key factors in the dechlorination of TCE in the zero-valent iron Fenton process have not been studied clearly. In the present study, the effects of the initial TCE concentration, initial H2O2 concentration, dosage of ZVI, initial pH, and temperature on TCE degradation in the ZVI Fenton process were studied. In addition, the structure and surface morphology of the ZVI used in this study were analyzed through scanning electron microscopy (SEM), N2 adsorption-desorption, and X-ray diffractometry (XRD). The experimental results demonstrated that the dosage of ZVI and initial H2O2 concentration had obvious impacts on TCE degradation. At a ZVI dosage of 2 g/L and an initial H2O2 concentration of 0.53 mol/L, more than 97% of TCE could be degraded within 24 h at 25 °C. We found that the ZVI Fenton process could efficiently degrade TCE at a broad pH range and room temperature, making it applicable to groundwater remediation. TCE degradation was associated with Fe2+ concentration. Spectroscopic analyses indicated that the oxide film formed on the ZVI surface was associated with Fe2+ concentration in enhanced TCE dechlorination. The ZVI Fenton process could work at a wide range of TCE concentrations (0-200 mg/L).
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Affiliation(s)
- Yangyang Sun
- College of Geographical Science, Harbin Normal University, Harbin 150000, China
| | - Shichao Liang
- Cooperative Economic Guidance Department, Suihua Agriculture and Rural Bureau, Suihua 152000, China
| | - Pengfei Li
- College of Geographical Science, Harbin Normal University, Harbin 150000, China
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Hu L, Xu X, Gui X, Liang J, Zhao L, Qiu H, Cao X. Time-dependent redistribution of soil arsenic induced by transformation of iron species during zero-valent iron biochar composites amendment: Effects on the bioaccessibility of As in soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 955:176956. [PMID: 39423896 DOI: 10.1016/j.scitotenv.2024.176956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2024] [Revised: 10/01/2024] [Accepted: 10/13/2024] [Indexed: 10/21/2024]
Abstract
Zero-valent iron biochar composites (ZVI/BC) are considered as effective amendments for arsenic (As)-contaminated soils. However, the mechanisms of transformation of various soil As species during ZVI/BC amendments remain unclear. This study investigated As transformation in four soils (namely, GX, ZJ, HB, and HN) treated with ZVI/BC for 65 days under two soil moisture conditions, unsaturated and oversaturated. Results showed that the 65-day treatment was divided into two stages based on the variation of labile As content. Within 2 days (stage 1), ZVI/BC addition quickly reduced labile As content by 5.91-90.3 % in soils under unsaturated conditions. During days 2-65 (stage 2), labile As ultimately decreased by 0.06-0.31 mg/kg in GX, ZJ, and HB while increasing by 22.1 mg/kg in HN soil, due to its lower pH value and Fe content. The variations of labile As were attributed to changes in multiple Fe minerals and associated As species. In stage 1, the corrosion of ZVI/BC generated amorphous Fe oxides to immobilize labile As, resulting in the accumulation of meta-stable As. In stage 2, amorphous Fe oxides were transformed into crystalline Fe oxides, resulting in the release and re-precipitation of As along with transformation, thus redistributing immobilized As into labile and stable As, which was evidenced by multiple methods, including chemical extraction, XRD, and TEM-EDX. The elevated soil moisture condition would enhance the corrosion of ZVI/BC in stage 1, further forming a reductive environment to facilitate the transformation of Fe minerals in stage 2. Besides, As bioaccessibility in soils was reduced by 10.8-38.7 % after ZVI/BC treatment in in-vitro gastrointestinal simulations. Overall, our study revealed the time-dependent transformation mechanism of soil As species and associated Fe minerals under different soil moisture with ZVI/BC treatments, and highlighted the effectiveness of ZVI/BC as a long-term amendment for As-contaminated soils.
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Affiliation(s)
- Liyang Hu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xiaoyun Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xiangyang Gui
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Jun Liang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Ling Zhao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hao Qiu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xinde Cao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Engineering Research Center for Solid Waste Treatment and Resource Recovery, Shanghai 200240, China.
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Yuan Y, Wei X, Zhu M, Cai Y, Wang Y, Dang Z, Yin H. Unravelling the removal mechanisms of trivalent arsenic by sulfidated nanoscale zero-valent iron: The crucial role of reactive oxygen species and the multiple effects of citric acid. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 916:170275. [PMID: 38262532 DOI: 10.1016/j.scitotenv.2024.170275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 01/06/2024] [Accepted: 01/17/2024] [Indexed: 01/25/2024]
Abstract
The remediation of arsenic-contaminated groundwater by sulfidated nanoscale zero-valent iron (S-nZVI) has raised considerable attention. However, the role of trivalent arsenic (As(III)) oxidation by S-nZVI in oxic conditions (S-nZVI/O2) remains controversial, and the comprehensive effect of citric acid (CA) prevalent in groundwater on As(III) removal by S-nZVI remains unclear. Herein, the mechanisms of reactive oxygen species (ROS) generation and multiple effects of CA on As(III) removal by S-nZVI/O2 were systematically explored. Results indicated that the removal efficiency of As(III) by S-nZVI/O2 (97.81 %) was prominently higher than that by S-nZVI (66.71 %), resulting from the significant production of ROS (mainly H2O2 and OH) under oxic conditions, which played a crucial role in promoting the As(III) oxidation. Additionally, CA had multiple effects on As(III) removal by S-nZVI/O2 system: (i) CA impeded the diffusion of As(III) towards S-nZVI and increased the secondary risk of immobilized As(III) re-releasing into the environment due to the Fe dissolution from S-nZVI; (ii) CA could significantly enhance the yields of OH from 25.29 to 133.00 μM via accelerating the redox cycle of Fe(II)/Fe(III) and increasing the oriented conversion rate of H2O2 to OH; (iii) CA could also enrich the types of ROS (such as O2- and 1O2) in favor of further As(III) oxidation. This study contributed novel findings regarding the control of As(III) contaminated groundwater using S-nZVI technologies.
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Affiliation(s)
- Yibo Yuan
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, Guangzhou 510006, China
| | - Xipeng Wei
- School of Environment, South China Normal University, Guangzhou 510006, China
| | - Minghan Zhu
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, Guangzhou 510006, China
| | - Yuhao Cai
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, Guangzhou 510006, China
| | - Yuanzheng Wang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, Guangzhou 510006, China
| | - Zhi Dang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, Guangzhou 510006, China
| | - Hua Yin
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, Guangzhou 510006, China.
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Zhong S, Fang L, Li X, Liu T, Wang P, Gao R, Chen G, Yin H, Yang Y, Huang F, Li F. Roles of Chloride and Sulfate Ions in Controlling Cadmium Transport in a Soil-Rice System as Evidenced by the Cd Isotope Fingerprint. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:17920-17929. [PMID: 37755710 DOI: 10.1021/acs.est.3c04132] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Abstract
Anions accompanying inorganic fertilizers, such as chloride and sulfate ions, potentially affect the solubility, uptake, and transport of Cd to rice grains. However, the role of anions in controlling Cd transport in the soil-soil solution-Fe plaque-rice plant continuum remains poorly understood. Cd isotope ratios were applied to Cd-contaminated soil pots, hydroponic rice, and adsorption experiments with or without KCl and K2SO4 treatments to decipher transport processes in the complex soil-rice system. The chloride and sulfate ions increased the Cd concentrations in the soil solution, Fe plaque, and rice plants. Accordingly, the magnitude of positive fractionation from soil to the soil solution was less pronounced, but that between soil and Fe plaque or rice plant is barely varied. The similar isotope composition of Fe plaque and soil, and the similar fractionation magnitude between Fe plaque and the solution and between goethite and the solution, suggested that desorption-sorption between iron oxides and the solution could be important at the soil-soil solution-Fe plaque continuum. This study reveals the roles of chloride and sulfate ions: (i) induce the mobility of light Cd isotopes from soil to the soil solution, (ii) chloro-Cd and sulfato-Cd complexes contribute to Cd immobilization in the Fe plaque and uptake into roots, and (iii) facilitate second leaves/node II-to-grain Cd transport within shoots. These results provide insights into the anion-induced Cd isotope effect in the soil-rice system and the roles of anions in facilitating Cd migration and transformation.
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Affiliation(s)
- Songxiong Zhong
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Liping Fang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Xiaomin Li
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
| | - Tongxu Liu
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Pei Wang
- College of Tropical Crops, Hainan University, Haikou 570228, China
| | - Ruichuan Gao
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Guojun Chen
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Haoming Yin
- CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Yang Yang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Fang Huang
- CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Fangbai Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
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Mlangeni AT, Chinthenga E, Kapito NJ, Namaumbo S, Feldmann J, Raab A. Safety of African grown rice: Comparative review of As, Cd, and Pb contamination in African rice and paddy fields. Heliyon 2023; 9:e18314. [PMID: 37519744 PMCID: PMC10375803 DOI: 10.1016/j.heliyon.2023.e18314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 07/07/2023] [Accepted: 07/13/2023] [Indexed: 08/01/2023] Open
Abstract
This review aimed to investigate the reported concentrations of arsenic (As), cadmium (Cd), and lead (Pb) in rice cultivated in Africa and African rice paddies compared to other regions. It also aimed to explore the factors influencing these concentrations and evaluate the associated health risks of elevated As, Cd, and Pb exposure. Relevant data were obtained from electronic databases such as PubMed, Scopus, and Google Scholar using specific keywords related to arsenic, cadmium, lead, rice, Africa, paddy, and grain. While the number of studies reporting the concentrations of As, Cd, and Pb in rice and rice paddies in Africa is relatively low compared to other regions, this review revealed that most of the African rice and paddy soils have low concentrations of these metals. However, some studies have reported elevated concentrations of As, Cd, and Pb in paddy fields, which is concerning due to the increased use of agrochemicals containing heavy metals in rice production. Nonetheless, agronomical interventions such as implementing alternate wetting and drying water management, cultivating cultivars with low accumulation of As, Cd, and Pb, amending rice fields with sorbents, and screening irrigation water can limit the bioaccumulation of these carcinogens in paddy fields using phytoremediation techniques. Therefore, we strongly urge African governments and organizations operating in Africa to enhance the capacity of rice farmers and extension officers in adopting approaches and practices that reduce the accumulation of these carcinogenic metals in rice. This is essential to achieve the sustainable development goal of providing safe food for all.
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Affiliation(s)
- Angstone Thembachako Mlangeni
- Department of Land and Water Resources, Natural Resources College, Lilongwe University of Agriculture and Natural Resources, Lilongwe, Malawi
| | - Evans Chinthenga
- Department of Land and Water Resources, Natural Resources College, Lilongwe University of Agriculture and Natural Resources, Lilongwe, Malawi
| | - Noel Jabesi Kapito
- Department of Land and Water Resources, Natural Resources College, Lilongwe University of Agriculture and Natural Resources, Lilongwe, Malawi
| | - Sydney Namaumbo
- Department of Land and Water Resources, Natural Resources College, Lilongwe University of Agriculture and Natural Resources, Lilongwe, Malawi
| | - Joerg Feldmann
- TESLA Analytical Chemistry, Institute of Chemistry, University of Graz, Austria
| | - Andrea Raab
- TESLA Analytical Chemistry, Institute of Chemistry, University of Graz, Austria
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Hu L, Zhang P, Xu X, Ren J, Zhao L, Qiu H, Cao X. Immobilization of arsenic in different contaminated soils by zero-valent iron-embedded biochar: Effect of soil characteristics and treatment conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 868:161597. [PMID: 36646221 DOI: 10.1016/j.scitotenv.2023.161597] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 01/09/2023] [Accepted: 01/10/2023] [Indexed: 06/17/2023]
Abstract
Although zero-valent iron-embedded biochar (ZVI-BC) has been proposed as an effective amendment for arsenic (As)-contaminated soils, the impacts of soil characteristics and treatment conditions on the remediation process remained poorly understood. Herein, the immobilization of As in four As-contaminated soils (i.e., smelting soil, storage soil, agricultural soil, and mining soil) by ZVI-BC under different amendment dosages, cultivation temperatures, and soil moisture contents were investigated. ZVI-BC showed high As immobilization capacity in all four soils via forming the AsFe co-precipitation, and the liable As was reduced by 82.4-97.0 % with a 2 % (w/w) amendment. The higher temperature could raise the concentration of liable As in all four soils, especially for the storage soil, in which liable As at 35 °C was almost 3 times of that at 25 °C after 50-days treatment, because the elevated temperature enhanced the destruction of the generated AsFe coprecipitation as well as the desorption of As in soils. Too much soil moisture was unfavorable for the As immobilization after 50-days treatment. Flooding tended to inhibit the community diversity of As-detoxicated bacteria, e.g., Halomonas, Bryobacter, and Anaerolinea, thus resulting in the release of liable As. According to the correlation analysis, the crucial influencing factor for As immobilization was different in four soils, which was determined by the soil properties and proportion of liable As. Our study indicates that ZVI-BC is an effective amendment for As immobilization under various conditions, and the biogeochemical processes of As-associated Fe minerals determine the As immobilization during amendment.
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Affiliation(s)
- Liyang Hu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Pengyu Zhang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xiaoyun Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Jia Ren
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ling Zhao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hao Qiu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xinde Cao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Engineering Research Center for Solid Waste Treatment and Resource Recovery, Shanghai 200240, China
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9
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Zhao Y, Li Q, Shi Q, Xi B, Zhang X, Jian Z, Zhou G, Meng X, Mao X, Kang D, Gong B. Mechanisms of Phosphate Removal by Micron-Scale Zero-Valent Iron. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2023.123706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2023]
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10
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Peng X, Chen N, Wei K, Li S, Shang H, Sun H, Zhang L. Zero-valent iron coupled calcium hydroxide: A highly efficient strategy for removal and magnetic separation of concentrated fluoride from acidic wastewater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:156336. [PMID: 35654177 DOI: 10.1016/j.scitotenv.2022.156336] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 05/07/2022] [Accepted: 05/25/2022] [Indexed: 06/15/2023]
Abstract
The removal of concentrated fluoride in acidic wastewater by the conventional Ca(OH)2 method is challenged by the insufficient efficiency and difficult separation of fine CaF2 precipitate. Herein, we construct a strategy to tackle these challenges by coupling zero-valent iron (ZVI) with Ca(OH)2. ZVI reduces fluoride concentration from 12,000 to 3980 mg L-1 under optimal conditions primarily through the in-situ growth of porous FeF2·4H2O shell on its surface, which simultaneously assists fluoride removal via adsorption. The residual fluoride after ZVI treatment then decreases to 6.74 mg L-1 via precipitation with Ca(OH)2. Interestingly, the iron ions dissolved from ZVI also participate in the precipitation to form magnetite. This co-precipitation reinforces the fluoride removal and meanwhile endows the resulted precipitates with magnetism, thus enabling the perfect solid-liquid separation by the magnetic field before discharge. The application prospect of this coupling strategy is further verified by its ability in decreasing the concentrations of fluoride and other coexisting heavy metals (Zn2+, Cd2+ and Pb2+) in real smeltery wastewater below their discharge limitations. This study provides a promising strategy for the treatment of concentrated fluoride in acidic wastewater and also highlights ZVI as a good candidate to couple with conventional methods for enhanced pollution control.
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Affiliation(s)
- Xing Peng
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China
| | - Na Chen
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China.
| | - Kai Wei
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China
| | - Shengbiao Li
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China
| | - Huan Shang
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China
| | - Hongwei Sun
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China.
| | - Lizhi Zhang
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of China
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11
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Wang P, Hu J, Wang Y, Liu T. Enhanced elimination of V 5+ in wastewater using zero-valent iron activated by ball milling: The overlooked crucial roles of energy input and sodium chloride. JOURNAL OF HAZARDOUS MATERIALS 2022; 435:129050. [PMID: 35650725 DOI: 10.1016/j.jhazmat.2022.129050] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/14/2022] [Accepted: 04/28/2022] [Indexed: 06/15/2023]
Abstract
The ball-milling technology, a highly efficient and cost-effective method, had excellent application prospects for overcoming passivation issues of normal zero-valent iron (ZVI) to enhance the decontamination efficiency. In this work, we investigated the effects and mechanisms of pH, process control agents (PCA), and main process parameters on the removal of V5+ using ball-milled zero-valent iron (ZVIbm). The results showed that ZVI was successfully activated due to mechanochemical action. The enhanced proton conductivity of ZVIbm leaded to the rapid production of more Fe2+, thereby resulting in an order of magnitude higher elimination of V5+ by ZVIbm than by ZVI under near-neutral conditions. In addition, the introduction of NaCl in the ball milling process could not only effectively alleviate the agglomeration phenomenon of ZVIbm, but also effectively enhance its activity. Unexpectedly, due to over-compaction and small size effects, excessive energy input weakened the reactivity of ZVIbm on V5+ elimination. Various characterization results confirmed that the removal of V5+ by ZVIbm was dominated by reduction and supplemented by adsorption. This work updated the basic understanding of the critical effects of process parameters and NaCl on ZVIbm in the remediation of vanadium-containing wastewater.
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Affiliation(s)
- Peng Wang
- Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin 300387, China; School of Geography and Environmental Sciences, Tianjin Normal University, Tianjin 300387, China
| | - Jian Hu
- The State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yidong Wang
- Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin 300387, China
| | - Tingyi Liu
- Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin 300387, China.
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12
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Cai X, Zhang Z, Yin N, Lu W, Du H, Yang M, Cui L, Chen S, Cui Y. Controlling microbial arsenite oxidation and mobilization in arsenite-adsorbed iron minerals: The Influence of pH conditions and mineralogical composition. JOURNAL OF HAZARDOUS MATERIALS 2022; 433:128778. [PMID: 35358812 DOI: 10.1016/j.jhazmat.2022.128778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/15/2022] [Accepted: 03/22/2022] [Indexed: 06/14/2023]
Abstract
The oxidation of aqueous arsenite (As(III)) by As(III)-oxidizing bacteria is known to attenuate the mobilization and toxicity of arsenic, and is regarded as potential method for As(III)-pollution remediation. However, during the interactions between As(III)-oxidizing bacteria and different As(III)-adsorbed soil Fe-minerals, the oxidation and partitioning of solid-phase As(III), as well as the controlling mechanisms, remain unclear. In this study, we therefore incubated three As(III)-adsorbed Fe-minerals with a typical As(III)-oxidizing bacteria (Pseudomonas sp. HN-1) at different pH conditions. After microbial oxidation, the percentage of arsenate (As(V)) was significantly higher at pH 7 (15-94%) and 9 (12-89%) than at pH 4 (6-50%) in all Fe-minerals. Incubation of As(III)-oxidizing bacteria promoted As-immobilization under acidic-conditions but As-mobilization under alkaline-conditions. Arsenic-X-ray adsorption spectroscopy results showed that solid-phase As(V) fraction in goethite, hematite and magnetite was 27-64%, 5-12% and 50-91%, respectively. Compared with the corner-sharing As(III)-adsorption complexes formed on magnetite, the edge-sharing complexes on hematite were significantly more stable towards microbial-oxidation. Additionally, the strong adhesion between strain HN-1 and hematite probably limit bacterial-activity and mobility, thereby inhibiting microbial As(III)-oxidation. Our findings elucidate the controlling mechanisms of microbial As(III)-oxidation in different As(III)-adsorbed Fe-minerals and demonstrate strain HN-1 is an excellent candidate for As(III)-remediation in soils containing goethite and magnetite.
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Affiliation(s)
- Xiaolin Cai
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Zhennan Zhang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Naiyi Yin
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Wenyi Lu
- Binzhou Institute of Technology, Binzhou, Shandong Province 256606, People's Republic of China
| | - Huili Du
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Mei Yang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Liwei Cui
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Shibao Chen
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, People's Republic of China.
| | - Yanshan Cui
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China.
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13
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Hu H, Zhang Q, Wang C, Chen M, Chen M. Mechanochemically synthesized Fe-Mn binary oxides for efficient As(III) removal: Insight into the origin of synergy action from mutual Fe and Mn doping. JOURNAL OF HAZARDOUS MATERIALS 2022; 424:127708. [PMID: 34801310 DOI: 10.1016/j.jhazmat.2021.127708] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 10/17/2021] [Accepted: 11/02/2021] [Indexed: 06/13/2023]
Abstract
Iron manganese oxide resources are widely derived from the geological structure, and their combinations play an important role in the migration and transformation of arsenic. Iron oxide and manganese oxide exist generally in a mixed state in Fe-Mn oxides synthesized via the well studied co-precipitation methods using potassium permanganate and manganese/iron sulfates. Herein, a newly designed Fe-Mn-O compositing oxide with Fe-MnO2, Mn-Fe2O3, (Fe0.67Mn0.33)OOH solid solution and FeOOH as the main components, simply through solvent-free mechanical ball milling pyrolusite (MnO2) and ferrihydrite (FeOOH) together has been reported. Atomic-scale integrations by doping Fe and Mn with each other were detected and an adsorption-oxidation bifunctionality was achieved, where Fe-doped MnO2 served as oxidizer for As(III) and amorphous/ground FeOOH acted as adsorbent first for As(III) and then As(V) from the oxidization. The maximal adsorption for As(III) could reach 44.99 mg/g and over 82.5% of As(III) was converted to As(V). More importantly, high removal ability of arsenic worked in a wide pH range of 2-10.5%, and 87.2% of its initial adsorption-oxidation capacity could be kept even after 5-cycles reuse for treating 20 mg/L As(III) with a dosage at 1 g/L. Together with the enhanced adsorption capacity by the milled FeOOH, surface electron transfer efficiency of the developed Fe-MnO2 surrounded with Mn-Fe2O3 has been studied for the first time to understand the oxidization effect to As(V). Besides the environment-friendliness of ball milling method, the prepared sample is quite stable without noticeable metal release into solution. Mechanism studies of arsenic removal by the as-prepared Fe-Mn-O oxide provide a new direction for improving the oxidation efficiency of MnO2 to As(III) based on the widely available cheap Mn and Fe oxides, contributing to the development of advanced oxidization process in the treatment of waste water.
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Affiliation(s)
- Huimin Hu
- School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Qiwu Zhang
- School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, China; Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Wuhan 430070, China.
| | - Chao Wang
- School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Min Chen
- School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Mengfei Chen
- School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, China
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14
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Wu S, Deng S, Ma Z, Liu Y, Yang Y, Jiang Y. Ferrous oxalate covered ZVI through ball-milling for enhanced catalytic oxidation of organic contaminants with persulfate. CHEMOSPHERE 2022; 287:132421. [PMID: 34600929 DOI: 10.1016/j.chemosphere.2021.132421] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 09/09/2021] [Accepted: 09/29/2021] [Indexed: 06/13/2023]
Abstract
Zero-valent iron (ZVI), with high reduction capacity and cost effectiveness, has been widely used as an activator for persulfate in remediation of organic pollutants. However, the existence of inherent iron oxide shell blocked the transfer of proton and further reduced its reactivity. In present study, a novel persulfate (PS) activator BZVI@OA was synthesized via ball milling ZVI with oxalic acid dihydrate. Scanning electron microscope, X-ray diffraction spectroscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectrometry and Time-of-flight secondary ion mass spectroscopy confirmed the original low proton conductive oxidation shell was replaced by a high proton conductive FeC2O4 shell. The generated shell significantly improved persulfate activated capacity, through which degradation rates of various contaminants were enhanced for 1.64 to 2.33 times. Dissolved oxalate was proved to form complexes with iron ions, dramatically reduced the potential difference and relieved the blocked cyclic conversion. Electron paramagnetic resonance and quenching experiments confirmed an inner sphere adsorption of PS on FeC2O4·2H2O shell which facilitated the peroxide bonds cleavage, leading high efficiency of ROS generation. The accelerated proton transition was confirmed with AC impedance method, resulting in fast and elevated surface bound Fe2+ for persulfate decomposition into active species. Furthermore, BZVI@OA/PS system demonstrated high tolerance over wide initial pH range and promising reusability within 6 cycles. This work clarifies an effective strategy for developing efficient modified ZVI as a PS activator for organic pollutant degradation in water.
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Affiliation(s)
- Shuxuan Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China; Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, School of Resources Environmental & Chemical Engineering, Nanchang University, Nanchang, 330031, PR China
| | - Sheng Deng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China.
| | - Zhifei Ma
- Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, School of Resources Environmental & Chemical Engineering, Nanchang University, Nanchang, 330031, PR China
| | - Yuhui Liu
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang, 330013, PR China
| | - Yu Yang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China.
| | - Yonghai Jiang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China
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15
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Eljamal O, Eljamal R, Maamoun I, Khalil AME, Shubair T, Falyouna O, Sugihara Y. Efficient treatment of ammonia-nitrogen contaminated waters by nano zero-valent iron/zeolite composite. CHEMOSPHERE 2022; 287:131990. [PMID: 34454218 DOI: 10.1016/j.chemosphere.2021.131990] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 07/16/2021] [Accepted: 08/22/2021] [Indexed: 06/13/2023]
Abstract
The aim of the present study is developing a magnetic nanoscale zero-valent iron/zeolite (nZVI/Z) composite towards the efficient removal of ammonia-nitrogen (NH4+-N) from aqueous solutions. Series of batch experiments were conducted to investigate the effect of different factors on the removal efficiency, including pH effect, aerobic/anaerobic, NH4+-N initial concentration, and temperature. The mixing mass ratio of nZVI/Z was optimized to reach the optimal ratio (0.25 g nZVI: 0.75 g zeolite), corresponding to the best removal efficiency of 85.7% after 120 min of reaction. Results revealed that nZVI/Z is efficient for NH4+-N removal from water at a wide pH range (3.0-10.0), with superiority to the neutral conditions. Moreover, aerobic ambient and normal temperature of 25 °C were the optimal conditions for the removal process of NH4+-N. Removal mechanisms involved electrostatic attraction, ion exchange, and adsorption. Generally, nZVI/Z has great potential towards the practical applications of NH4+-N removal from water.
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Affiliation(s)
- Osama Eljamal
- Water and Environmental Engineering Laboratory, Department of Advanced Environmental Science and Engineering, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasuga-Koen Kasuga, Fukuoka, 816-8580, Japan.
| | - Ramadan Eljamal
- Water and Environmental Engineering Laboratory, Department of Advanced Environmental Science and Engineering, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasuga-Koen Kasuga, Fukuoka, 816-8580, Japan
| | - Ibrahim Maamoun
- Water and Environmental Engineering Laboratory, Department of Advanced Environmental Science and Engineering, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasuga-Koen Kasuga, Fukuoka, 816-8580, Japan
| | - Ahmed M E Khalil
- College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, Devon, EX4 4QF, UK; Department of Chemical Engineering, Faculty of Engineering, Cairo University, Giza, 12613, Egypt
| | - Tamer Shubair
- Water and Environmental Engineering Laboratory, Department of Advanced Environmental Science and Engineering, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasuga-Koen Kasuga, Fukuoka, 816-8580, Japan
| | - Omar Falyouna
- Water and Environmental Engineering Laboratory, Department of Advanced Environmental Science and Engineering, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasuga-Koen Kasuga, Fukuoka, 816-8580, Japan
| | - Yuji Sugihara
- Environmental Fluid Science Laboratory, Department of Advanced Environmental Science and Engineering, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasuga-Koen Kasuga, Fukuoka, 816-8580, Japan
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16
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Mlangeni AT, Lancaster ST, Raab A, Krupp EM, Norton GJ, Feldmann J. Higher zero valent iron soil amendments dosages markedly inhibit accumulation of As in Faya and Kilombero cultivars compared to Cd. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 794:148735. [PMID: 34323768 DOI: 10.1016/j.scitotenv.2021.148735] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 05/27/2021] [Accepted: 06/25/2021] [Indexed: 06/13/2023]
Abstract
Impact of zero valent iron (Fe°) amendment on grain-yield (GY) and grain-As and Cd accumulation in rice (Oryza sativa L.) cultivars Kilombero and Faya were investigated. Rice plants were amended with Fe° dosages of 0, 3.1, 6.2, and 12.4 g Fe°/kg soil in pots in greenhouse experiments under continuous flooding water regime. GY in each treatment was determined at maturity, grain-As and Cd and arsenic species concentrations were determined using ICP-MS and HPLC tandem ICP-MS respectively. Mean GY in Faya (5.5 ± 1.0 g/plant) and Kilombero (4.2 ± 0.4 g/plant) amended with at least 6.2 g Fe°/kg soil were at least 57% and 22% respectively significantly higher (F = 11; p = 0.003) than that in controls (3.7 ± 0.6 and 3.4 ± 0.4 g/plant). For As bioaccumulation, mean grain-As concentration in Faya T2 (≤227 ± 32 μg/kg) and Kilombero (≤218 ± 25 μg/kg) amended with at least 6.2 g Fe°/kg soil in were at least 83% and 77% respectively significantly lower (F = 7; p = 0.004) than that in controls (973 ± 43 μg/kg and 1278 ± 208 μg/kg). Mean grain-Cd concentrations in Faya (10 ± 2 μg/kg) and Kilombero (13 ± 3 μg/kg) amended with corresponding Fe° dosages were at least 26% and 39% significantly lower (F = 4; p < 0.05) than that in controls (18 ± 3 and 23 ± 1 μg/kg). Results indicated that amending Kilombero with at least 6.2 g/kg Fe° effectively optimally regulated both grain-As and Cd accumulation to values lower than the European Commission's legislated maximum contaminant limits (MCL) of 200 μg/kg without negating grain yield benefits. Our results suggest that bioaccumulation of both As and Cd in rice grains may be completely circumvented by adopting cultivar-specific Fe° amendment dosage.
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Affiliation(s)
- Angstone Thembachako Mlangeni
- Natural Resources College, Lilongwe University of Agriculture and Natural Resources, Malawi; Trace Elements Speciation Laboratory Aberdeen (TESLA), Department of Chemistry, University of Aberdeen, Scotland, United Kingdom.
| | - Shaun T Lancaster
- P S Analytical, Orpington, Kent, United Kingdom; Trace Elements Speciation Laboratory Aberdeen (TESLA), Department of Chemistry, University of Aberdeen, Scotland, United Kingdom
| | - Andrea Raab
- Trace Elements Speciation Laboratory Aberdeen (TESLA), Department of Chemistry, University of Aberdeen, Scotland, United Kingdom
| | - Eva M Krupp
- Trace Elements Speciation Laboratory Aberdeen (TESLA), Department of Chemistry, University of Aberdeen, Scotland, United Kingdom
| | - Gareth J Norton
- School of Biological Sciences, University of Aberdeen, United Kingdom
| | - Joerg Feldmann
- Trace Elements Speciation Laboratory Aberdeen (TESLA), Department of Chemistry, University of Aberdeen, Scotland, United Kingdom.
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17
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Wang X, Zhang Y, Wang Z, Xu C, Tratnyek PG. Advances in metal(loid) oxyanion removal by zerovalent iron: Kinetics, pathways, and mechanisms. CHEMOSPHERE 2021; 280:130766. [PMID: 34162087 DOI: 10.1016/j.chemosphere.2021.130766] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/23/2021] [Accepted: 04/24/2021] [Indexed: 06/13/2023]
Abstract
Metal(loid) oxyanions in groundwater, surface water, and wastewater can have harmful effects on human or ecological health due to their high toxicity, mobility, and lack of degradation. In recent years, the removal of metal(loid) oxyanions using zerovalent iron (ZVI) has been the subject of many studies, but the full scope of this literature has not been systematically reviewed. The main elements that form metal(loid) oxyanions under environmental conditions are Cr(VI), As(V and III), Sb(V and III), Tc(VII), Re(VII), Mo(VI), V(V), etc. The removal mechanisms of metal(loid) oxyanions by ZVI may involve redox reactions, adsorption, precipitation, and coprecipitation, usually with one of these mechanisms being the main reaction pathway and the other playing auxiliary roles. However, the removal mechanisms are coupled to the reactions involved in corrosion of Fe(0) and reaction conditions. The layer of iron oxyhydroxides that forms on ZVI during corrosion mediates the sequestration of metal(loid) oxyanions. This review summarizes most of the currently available data on mechanisms and performance (e.g., kinetics) of removal of the most widely studies metal(loid) oxyanion contaminants (Cr, As, Sb) by different types of ZVI typically used in wastewater treatment, as well as ZVI that has been sulfidated or combination with catalytic bimetals.
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Affiliation(s)
- Xiao Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China
| | - Yue Zhang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China
| | - Zhiwei Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China
| | - Chunhua Xu
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China.
| | - Paul G Tratnyek
- OHSU-PSU School of Public Health, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA.
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18
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Li M, He Z, Zhong H, Hu L, Sun W. Multi-walled carbon nanotubes facilitated Roxarsone elimination in SR-AOPs by accelerating electron transfer in modified electrolytic manganese residue and forming surface activated-complexes. WATER RESEARCH 2021; 200:117266. [PMID: 34058487 DOI: 10.1016/j.watres.2021.117266] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 04/09/2021] [Accepted: 05/15/2021] [Indexed: 06/12/2023]
Abstract
A novel catalyst (MT/EMR) used for SR-AOPs with high removal efficiency toward roxarsone (ROX) (90.96% within 60 min) was prepared for the first time by ball milling multi-walled carbon nanotubes (MWCNTs) with electrolytic manganese residue (EMR). The incorporation of MWCNTs could improve the adsorption capacity and accelerate the transformation of metals in EMR with partial mass loss to facilitate the PDS activation. Additionally, pH test, quenching experiment and electrochemical test verified a two-electron pathway involving surface activated-complex contributed to the directly ROX oxidization. Benefit from the introduction of MWCNTs, the degradation rate (kobs) of catalytic reaction was increased by 10.1 times compared with that of single-EMR. Additionally, the M-O-C (M=Fe or Mn) bonds in MT/EMR making the catalyst more stable than EMR. This work provided a novel and effective strategy to establish waste solid-based catalysts for green preparation and expanded the adsorption-oxidation technology to solve the problem of organoarsenic pollution.
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Affiliation(s)
- Mengke Li
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Zhiguo He
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China; Faculty of Materials Metallurgy & Chemistry, Jiangxi University of Science & Technology, Ganzhou, Jiangxi, 341000, China.
| | - Hui Zhong
- School of Life Science, Central South University, Changsha, 410012, China.
| | - Liang Hu
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Wei Sun
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China
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19
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Shi W, Song W, Zheng J, Luo Y, Qile G, Lü S, Lü X, Zhou B, Lü C, He J. Factors and pathways regulating the release and transformation of arsenic mediated by reduction processes of dissimilated iron and sulfate. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 768:144697. [PMID: 33454476 DOI: 10.1016/j.scitotenv.2020.144697] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 12/20/2020] [Accepted: 12/21/2020] [Indexed: 06/12/2023]
Abstract
The driving process and explanatory factors regulating the transformation and migration of arsenic (As) mediated by dissimilatory iron reducing bacteria (DFeRB) and sulfate reducing bacteria (SRB) remain poorly understood. The novelty of this study is to explore the driving process and key environmental factors governing As mobilization mediated by DFeRB and SRB based on continuous As speciation and environmental parameter monitoring in a sediment-water system. The results illustrate the reduction process mediated by DFeRB and SRB significantly promotes the reduction of As(V) and the endogenous release of As. However, in the DFeRB and SRB mediated reductions, the main driving process and key explanatory factors that dominate the As mobility are significantly different. DFeRB has significant effects on the reductive dissolution and re-distribution of Fe(III) oxyhydroxides and As-containing Fe(III) minerals and on adsorption-desorption, which in turn influenced the transformation of iron species and the release and ecotoxicity of As. Meanwhile, the environmental factors that affect As mobility depend on Fe2+ and Fe3+ in DFeRB-induced reduction, presenting two main pathways: the process of As mobilization mediated by DFeRB, and the process influenced by the inorganic phosphorus involved in the competitive adsorption and anion exchange. Significantly different from DFeRB, the effects of SRB on As behavior mainly occur by influencing the adsorbed As, pyrite, and As sulfides in the sediments and through the formation of sulfides during the sulfate reduction. The main pathways of As mobilization reflect the direct effects of SRB, S2-, and Fe2+. In addition, the role of NH4+-N in the driving process of As mobility is more pronounced in SRB-induced reduction. NO3--N is an essential factor affecting As mobility, but the effects of NO3--N on As lead to non-significant pathways. This work provides insights into the environmental effects of DFeRB and SRB on the biogeochemical cycle of As.
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Affiliation(s)
- Wenjing Shi
- School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
| | - Wenjie Song
- Pioneer College, Inner Mongolia University, Hohhot 010021, China
| | - Jinli Zheng
- School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
| | - Yu Luo
- School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
| | - Geer Qile
- School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
| | - Sijie Lü
- School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
| | - Xiangmeng Lü
- School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China
| | - Bin Zhou
- Tianjin Academy of Eco-Environmental Sciences, Tianjin 300191, China
| | - Changwei Lü
- School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China; Institute of Environmental Geology, Inner Mongolia University, Hohhot 010021, China.
| | - Jiang He
- School of Ecology and Environment, Inner Mongolia University, Hohhot 010021, China; Institute of Environmental Geology, Inner Mongolia University, Hohhot 010021, China.
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20
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Liu L, Qiao Q, Tan W, Sun X, Liu C, Dang Z, Qiu G. Arsenic detoxification by iron-manganese nodules under electrochemically controlled redox: Mechanism and application. JOURNAL OF HAZARDOUS MATERIALS 2021; 403:123912. [PMID: 33264965 DOI: 10.1016/j.jhazmat.2020.123912] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/05/2020] [Accepted: 09/07/2020] [Indexed: 06/12/2023]
Abstract
Iron-manganese binary oxides are characterized by high oxidation and adsorption capability and widely applied to arsenic (As) detoxification in contaminated waters. Despite of their lower preparation cost relative to synthesized iron-manganese binary oxides, the low adsorption capacity of natural iron-manganese oxides largely hinders their application. Here, electrochemically controlled redox was employed to improve the As(III,V) removal performance of iron-manganese nodules in a symmetric electrode system, and the removal mechanism and electrode reusability were also examined. Experimental results showed that both the electrochemical reduction and oxidation of birnessite in iron-manganese nodules contributed much to As(III,V) removal. Higher cell voltage facilitated a higher removal efficiency of total As within 0-1.2 V, which reached 94.7% at 1.2 V for actual As-containing wastewater (4068 μg L-1). The efficiency was obviously higher than that at open circuit (81.4%). Under electrode polarity reversal, the alternating reduction dissolution and oxidation recrystallization of birnessite in iron-manganese nodules promoted their contact with As, enhancing the total As removal efficiency from 75.6% to 91.8% after five times of repeated adsorption. This research clarifies the effect of electrochemical redox on As(III,V) detoxification by iron-manganese oxides, and expands the application of natural iron-manganese nodules in the treatment of As-contaminated wastewaters.
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Affiliation(s)
- Lihu Liu
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, College of Resources and Environment, Interdisciplinary Sciences Research Institute, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
| | - Qi Qiao
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, College of Resources and Environment, Interdisciplinary Sciences Research Institute, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
| | - Wenfeng Tan
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, College of Resources and Environment, Interdisciplinary Sciences Research Institute, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
| | - Xuecheng Sun
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, College of Resources and Environment, Interdisciplinary Sciences Research Institute, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
| | - Chengshuai Liu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, Guizhou Province, China
| | - Zhi Dang
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, Guangdong Province, China
| | - Guohong Qiu
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, College of Resources and Environment, Interdisciplinary Sciences Research Institute, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China.
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21
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Fan J, Chen X, Xu Z, Xu X, Zhao L, Qiu H, Cao X. One-pot synthesis of nZVI-embedded biochar for remediation of two mining arsenic-contaminated soils: Arsenic immobilization associated with iron transformation. JOURNAL OF HAZARDOUS MATERIALS 2020; 398:122901. [PMID: 32470770 DOI: 10.1016/j.jhazmat.2020.122901] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 04/28/2020] [Accepted: 05/03/2020] [Indexed: 06/11/2023]
Abstract
Waste biomass derived biochar has been proven as an effective and friendly amendment for remediation of heavy metals-contaminated soil. However, biochar is less effective for soil arsenic (As) immobilization in most cases. To improve the ability of biochar for As immobilization, in this study, the composite of biochar embedded with nano zero valent iron (nZVI/BC) was prepared through simple one-step pyrolysis of biomass sawdust and Fe2O3 mixture and then applied for amendment of two mining As-contaminated soils. Pristine sawdust biochar (BC) and nZVI alone or in combination were included for comparison. Results show that the prepared nZVI/BC contained about 40% Fe which was mainly present as Fe°. All treatments except BC reduced As concentration in (NH4)2SO4 extraction and gastrointestinal solution. Particularly, nZVI/BC reduced the labile As in (NH4)2SO4 extraction in two soils by over 93% and bioaccessible As in gastrointestinal solution decreased by over 85%. Fe° on the surface of nZVI/BC was oxidized into amorphous FeOOH which adsorbed or co-precipitated with As. Meanwhile, Ca-Fe-As-O and Al-Fe-As-O co-precipitated at the interface between nZVI/BC and two soils enriched with Ca and Al, respectively. Results indicated that the simply-prepared nZVI/BC was a promising material for remediation of As-contaminated soils.
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Affiliation(s)
- Jin Fan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xiang Chen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Zibo Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xiaoyun Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Ling Zhao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Hao Qiu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xinde Cao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China; Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, Shanghai Jiao Tong University, Shanghai, 200240, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200090, China.
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22
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Wan H, Islam MS, Qian D, Ormsbee L, Bhattacharyya D. Reductive Degradation of CCl 4 by Sulfidized Fe and Pd-Fe Nanoparticles: Kinetics, Longevity, and Morphology Aspects. CHEMICAL ENGINEERING JOURNAL (LAUSANNE, SWITZERLAND : 1996) 2020; 394:125013. [PMID: 33184558 PMCID: PMC7654737 DOI: 10.1016/j.cej.2020.125013] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
In this study a systematic comparison in morphology, long-term degradation, regeneration and reuse were conducted between palladized and sulfidized nanoscale zero-valent iron (Pd-Fe and S-Fe). Pd-Fe and S-Fe were prepared, after the synthesis of precursor Fe0 nanoparticles (spherical, ~35 nm radius) for carbon tetrachloride (CTC) treatment. With HAADF-TEM-EDS characterization, dispersive Pd islets were found on the Fe core of Pd-Fe. However, the Fe core was covered by the FeSx shell of S-Fe (FeS/FeS2 = 0.47). With an excessive Pd dose (10 mol%), the Pd-Fe were dramatically deformed to dendritic structures which significantly decreased reactivity. For CTC degradation, Pd-Fe (0.3 atomic% Pd) increased the degradation rate by 20-fold (ksa= 0.580 Lm-2min-1) while S-Fe presented a greater life time. The major intermediate chloroform (CF) was further degraded and less than 5% CF was observed after 24 h using Pd-Fe or S-Fe while above 50% CF remained using Fe. During aging, the Fe core was converted to FeOOH and Fe3O4/γ-Fe2O3. The restoration of Fe0 was achieved using NaBH4, which regenerated Fe and Pd-Fe. However, the formed FeSx shell on S-Fe was disappeared. The results suggest that S-Fe extends longevity of Fe, but the loss of FeSx after aging makes S-Fe eventually perform like Fe in terms of CTC degradation.
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Affiliation(s)
- Hongyi Wan
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, Kentucky 40506-0046
| | - Mohammad Saiful Islam
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, Kentucky 40506-0046
| | - Dali Qian
- Electron Microscopy Center, College of Engineering, University of Kentucky, Lexington, Kentucky 40506-0046
| | - Lindell Ormsbee
- Department of Civil Engineering, University of Kentucky, Lexington, Kentucky 40506-0046
| | - Dibakar Bhattacharyya
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, Kentucky 40506-0046
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23
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Shi Q, Zhang S, Ge J, Wei J, Christodoulatos C, Korfiatis GP, Meng X. Lead immobilization by phosphate in the presence of iron oxides: Adsorption versus precipitation. WATER RESEARCH 2020; 179:115853. [PMID: 32388052 DOI: 10.1016/j.watres.2020.115853] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 04/14/2020] [Accepted: 04/18/2020] [Indexed: 06/11/2023]
Abstract
As a commonly used corrosion inhibitor, phosphate (PO4) has a complicated effect on the fate and transport of lead (Pb) in drinking water systems. While the formation of pyromorphite has been recognized to be the major driving force of the Pb immobilization mechanism, the role of adsorption on iron oxides is still not clear. This study aims to clarify the contributions of adsorption and precipitation to Pb removal in a system containing both iron oxides and PO4. A combination of batch experiments, X-ray absorption spectroscopy, infrared spectroscopy, and electron spectroscopy was employed to distinguish the adsorbed and precipitated Pb species. The results indicated that the adsorption of Pb on iron oxides still occurred even when the solution was supersaturated to pyromorphite (i.e., 5 mg/L P with 0.1-30 mg/L Pb in 0.01 M NaCl solution at neutral pH). In the tap water containing 0.92 mg/L P and 1 mg/L Pb, adsorption on iron oxides contributed more (62-67%) than precipitation (33-38%) in terms of Pb removal. Surprisingly, the pre-formed pyromorphite is transformed to adsorbed species after mixing with iron oxides in water for 24 h. The illustration of this transformation is important to understand the immobilization mechanisms and transport behaviors of Pb in drinking water systems after the utilization of PO4.
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Affiliation(s)
- Qiantao Shi
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ, 07030, United States
| | - Shujuan Zhang
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ, 07030, United States
| | - Jie Ge
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ, 07030, United States
| | - Jinshan Wei
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ, 07030, United States
| | - Christos Christodoulatos
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ, 07030, United States
| | - George P Korfiatis
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ, 07030, United States
| | - Xiaoguang Meng
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ, 07030, United States. http://
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24
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Shi Q, Zhang S, Korfiatis GP, Christodoulatos C, Meng X. Identifying the existence and molecular structure of the dissolved HCO 3-Ca-As(V) complex in water. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 724:138216. [PMID: 32272407 DOI: 10.1016/j.scitotenv.2020.138216] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/18/2020] [Accepted: 03/24/2020] [Indexed: 06/11/2023]
Abstract
Calcium (Ca2+) and bicarbonate (HCO3-) ions co-exist with arsenic (As) in natural water systems, while Ca-based materials such as lime and cement are widely used to immobilize As(V) in contaminated solids. In this paper, a new dissolved ternary complex, HCO3-Ca-As(V), was discovered and its molecular structure was identified. The results from the batch experiments showed that adding As(V) to the solutions containing Ca2+ and HCO3- increased the dissolved Ca concentration from 4.8 to 73.2 mg/L at pH 11. Both infrared and X-ray absorption spectroscopy indicated the presence of dissolved HCO3-Ca-As(V) complex. Based on the quantitative geometric information obtained from the spectroscopic results, the molecule of (OH)OC-O-(OH2)4Ca-O2-As(OH)2 was identified by the density functional theory (DFT) calculation. Although Ca2+ and As(V) can form complex without HCO3-, the presence of HCO3- further enhanced the stability of the dissolved Ca complex, as evidenced by the lower binding energy (BE) of HCO3-Ca-As(V) (-329.1959 kJ/mol) than Ca-As(V) (4.7171 kJ/mol). The discovery of dissolved HCO3-Ca-As(V) complex is important for understanding the mobility of As(V) in natural water, and the possible release of As(V) in contaminated solids treated with Ca-based materials.
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Affiliation(s)
- Qiantao Shi
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030, United States.
| | - Shujuan Zhang
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030, United States
| | - George P Korfiatis
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030, United States
| | - Christos Christodoulatos
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030, United States
| | - Xiaoguang Meng
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030, United States.
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25
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Qiao Q, Yang X, Liu L, Luo Y, Tan W, Liu C, Dang Z, Qiu G. Electrochemical adsorption of cadmium and arsenic by natural Fe-Mn nodules. JOURNAL OF HAZARDOUS MATERIALS 2020; 390:122165. [PMID: 32006848 DOI: 10.1016/j.jhazmat.2020.122165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 01/17/2020] [Accepted: 01/21/2020] [Indexed: 06/10/2023]
Abstract
Fe-Mn nodules are widely distributed and regarded as excellent adsorbents for heavy metals. Their adsorption-desorption reactions with heavy metal ions are usually accompanied by redox processes. Herein, Fe-Mn nodules were used as adsorbents for Cd(II) and As(III,V) at a constant cell voltage under electrochemically controlled reduction and oxidation, respectively. The results showed that the adsorption performance for Cd(II) and As(III,V) was enhanced respectively due to the decrease and increase of Mn average oxidation state (Mn AOS) in Fe-Mn nodules. High birnessite content and Mn average oxidation state (Mn AOS) improved the adsorption of Cd(II) and As(III,V). The adsorption capacity for Cd(II) and total As increased with increasing voltage. With increasing pH, the adsorption capacity for Cd(II) increased first and then reached equilibrium, and that of total As decreased and then increased. The Cd(II) electrochemical adsorption capacity (129.9 mg g-1) and the removal efficiency for total As at 1.2 V (83.6 %) in As-containing wastewater at an initial concentration of 4.068 mg L-1 were remarkably higher than the corresponding inorganic adsorption performance (9.46 mg g-1 and 70.5 %, respectively). This work may further promote the application of natural Fe-Mn nodules in the adsorption of heavy metals from wastewaters.
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Affiliation(s)
- Qi Qiao
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
| | - Xiong Yang
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
| | - Lihu Liu
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
| | - Yao Luo
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
| | - Wenfeng Tan
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China
| | - Chengshuai Liu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Zhi Dang
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China
| | - Guohong Qiu
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Soil Environment and Pollution Remediation, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, China.
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26
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Xie S, Xiao X, Tan W, Lv J, Deng Q, Fang Q. Influence of Leifsonia sp. on U(VI) removal efficiency and the Fe-U precipitates by zero-valent iron. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:5584-5594. [PMID: 31853852 DOI: 10.1007/s11356-019-07306-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 12/05/2019] [Indexed: 06/10/2023]
Abstract
Zero-valent iron (ZVI) has been widely applied to the remediation of uranium (U)-contaminated water. Notably, indigenous bacteria may possess potential positive or unfavorable influence on the mechanism and stability of Fe-U precipitates. However, the focus of the researches in this field has mainly been on physical and/or chemical aspects. In this study, batch experiments were conducted to explore the effects of an indigenous bacterium (Leifsonia sp.) on Fe-U precipitates and the corresponding removal efficiency by ZVI under different environmental factors. The results showed that the removal rate and capacity of U(VI) was significantly inhibited and decreased by ZVI when the pH increased to near-neutral level (pH = 6~8). However, in the ZVI + Leifsonia sp. coexistence system, the U(VI) removal efficiency were maintained at high levels (over 90%) within the experimental scope (pH = 3~8). This revealed that Leifsonia sp. had a synergistic effect on U(VI) remove by ZVI. According to scanning electron microscope and energy dispersive X-ray detector (SEM-EDX) analysis, dense scaly uranium-phosphate precipitation was observed on ZVI + Leifsonia sp. surface. The X-photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) analysis indicated that Leifsonia sp. facilitated the generation of U(VI)-phosphates precipitates. The X-ray diffraction (XRD) analyses further revealed that new substances, such as (Fe(II)Fe(III)2(PO4)2(OH)2), Fe(II)(UO2)2(PO4)2·8H2O, Fe(II)Fe(III)5(PO4)4(OH)2·4H2O, etc., were produced in the coexisting system of ZVI and Leifsonia sp. This study provides new insights on the feasibility and validity of site application of ZVI to U(VI)-contaminated subsurface water in situ. Graphical abstract.
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Affiliation(s)
- Shuibo Xie
- Key Discipline Laboratory for National Defense of Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, 421001, China
| | - Xue Xiao
- School of Resource Environment and Safety Engineering, University of South China, Hengyang, 421001, China
| | - Wenfa Tan
- School of Resource Environment and Safety Engineering, University of South China, Hengyang, 421001, China.
- Hengyang Key Laboratory of Soil Pollution Control and Remediation, University of South China, Hengyang, 421001, China.
| | - Junwen Lv
- School of Resource Environment and Safety Engineering, University of South China, Hengyang, 421001, China
| | - Qinwen Deng
- Hengyang Key Laboratory of Soil Pollution Control and Remediation, University of South China, Hengyang, 421001, China
| | - Qi Fang
- School of Resource Environment and Safety Engineering, University of South China, Hengyang, 421001, China
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27
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Wei Y, Wei S, Liu C, Chen T, Tang Y, Ma J, Yin K, Luo S. Efficient removal of arsenic from groundwater using iron oxide nanoneedle array-decorated biochar fibers with high Fe utilization and fast adsorption kinetics. WATER RESEARCH 2019; 167:115107. [PMID: 31563708 DOI: 10.1016/j.watres.2019.115107] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 09/19/2019] [Accepted: 09/21/2019] [Indexed: 05/21/2023]
Abstract
Although Fe-based biochar adsorbents are attractive for removing arsenic from water due to their advantages of costing little and being producible at a large scale, the practical applications of these granular adsorbents are mainly limited by low Fe utilization and slow adsorption kinetics. In this study, iron oxide nanoneedle array-decorated biochar fibers (Fe-NN/BFs) adsorbents have been prepared through a simple hydrothermal reaction. The vertical growth of iron oxide nanoneedle arrays on the surface of biochar fibers maximizes Fe utilization and shortens As diffusion distance, thereby increasing As removal kinetics and capacity. Batch experiments show that the adsorption capacities of Fe-NN/BFs for As(V) and As(III) reach to 93.94 and 70.22 mg/g-Fe at pH 7.0, respectively. As(V) levels (275 μg/L) in groundwater are rapidly reduced (less than 5 min) to below 10 μg/L using Fe-NN/BFs (1 g/L) at pH 6.7. Similar As(III) levels can be reduced to below 10 μg/L within 30 min by Fe-NN/BFs (1.5 g/L). In fixed-bed experiments, the treatment volumes of As(V) and As(III) spiked groundwater reach to 2900 BV (26.2 L) and 2500 BV (22.6 L), respectively, using two columns packed with Fe-NN/BFs in tandem (C0 = 275 μg/L, 2 g of adsorbents in each column). When the As concentration in the influent is reduced to 50 μg/L (As(V): 25 μg/L + As(III): 25 μg/L), the treatment volume using one column reaches up to 11000 BV. The Fe-NN/BFs packed column can be easily regenerated and reused many times. After four regenerations, the treatment volume of As(V) and As(III) were reduced by 10.4% and 22.8%, respectively.
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Affiliation(s)
- Yuanfeng Wei
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, 410082, PR China
| | - Shudan Wei
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, 410082, PR China
| | - Chengbin Liu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, 410082, PR China.
| | - Tao Chen
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, 410082, PR China
| | - Yanhong Tang
- College of Materials Science and Engineering, Hunan University, Changsha, 410082, PR China.
| | - Jianhong Ma
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China
| | - Kai Yin
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, 410082, PR China
| | - Shenglian Luo
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, 410082, PR China
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28
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Zhang S, Shi Q, Christodoulatos C, Meng X. Lead and cadmium adsorption by electrospun PVA/PAA nanofibers: Batch, spectroscopic, and modeling study. CHEMOSPHERE 2019; 233:405-413. [PMID: 31176904 DOI: 10.1016/j.chemosphere.2019.05.190] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 04/26/2019] [Accepted: 05/22/2019] [Indexed: 06/09/2023]
Abstract
Water-stable PVA/PAA nanofibers were fabricated through electrospinning and evaluated for their performance in lead (Pb(II)) and cadmium (Cd(II)) removal from water in a batch experiment. The adsorption mechanism of Pb(II) was explored using the extended X-ray absorption fine structure (EXAFS) spectroscopic analysis. The PVA/PAA nanofibers showed a pH-dependent behavior for heavy metal removal, and its adsorption capacities for Pb(II) and Cd(II) could reach as high as 159 and 102 mg/g, respectively. The calcium ion (Ca(II)) had no effect on Pb(II) removal at pH 5.0 whereas it significantly reduced Cd(II) removal at pH 7.0. The adsorption of Pb(II) and Cd(II) was spontaneous and exothermic in nature with a decrease in randomness. The saturated PVA/PAA nanofibers could be regenerated using acidic solutions for reuse. The Fourier-transform infrared (FTIR) spectroscopic analysis indicated the formation of surface complexes between adsorbed Pb(II) and Cd(II) and carboxyl groups on PVA/PAA nanofibers. Moreover, EXAFS analysis suggested that a Pb(II) cation was chelated with three carboxyl groups on the nanofibers. This molecular-level adsorption structure was successfully implemented into a surface complexation model for the prediction of the macroscopic Pb(II) and Cd(II) adsorption behaviors. The results gained from this study provided complementary information on heavy metal removal by a new generation of adsorbents and improved the fundamental understanding for the removal process.
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Affiliation(s)
- Shujuan Zhang
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030, United States
| | - Qiantao Shi
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030, United States
| | - Christos Christodoulatos
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030, United States
| | - Xiaoguang Meng
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030, United States.
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29
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Zhang D, Li Y, Tong S, Jiang X, Wang L, Sun X, Li J, Liu X, Shen J. Biochar supported sulfide-modified nanoscale zero-valent iron for the reduction of nitrobenzene. RSC Adv 2018; 8:22161-22168. [PMID: 35541698 PMCID: PMC9081282 DOI: 10.1039/c8ra04314k] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 06/06/2018] [Indexed: 11/22/2022] Open
Abstract
Sulfide-modified nanoscale zerovalent iron (S-nZVI) was effectively utilized for the reduction of various contaminants, despite its applicability being limited due to agglomeration, oxidation and electron loss. In this study, biochar (BC)-supported S-nZVI was prepared to enhance the reactivity of S-nZVI for nitrobenzene (NB) reduction. Scanning electron microscopy images showed that the S-nZVI particles were well-dispersed on the BC surface as well as in the channels. NB removal and aniline formation could be significantly enhanced by using S-nZVI@BC, as compared to S-nZVI and blank BC. NB removal by S-nZVI@BC followed the pseudo second-order kinetics model and Langmuir isotherm model, suggesting hybrid chemical reaction-sorption was involved. Furthermore, a possible reaction mechanism for enhanced NB removal by S-nZVI@BC was proposed, including chemical adsorption of NB onto S-nZVI@BC, direct reduction by S-nZVI and enhanced electron transfer. The high reducibility of S-nZVI@BC as well as its excellent antioxidation ability and reusability demonstrated its promising prospects in remediation applications.
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Affiliation(s)
- Dejin Zhang
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology Nanjing 210094 Jiangsu Province China +86 25 84315941 +86 25 84303965 +86 25 84315941 +86 25 84303965
| | - Yang Li
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology Nanjing 210094 Jiangsu Province China +86 25 84315941 +86 25 84303965 +86 25 84315941 +86 25 84303965
| | - Siqi Tong
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology Nanjing 210094 Jiangsu Province China +86 25 84315941 +86 25 84303965 +86 25 84315941 +86 25 84303965
| | - Xinbai Jiang
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology Nanjing 210094 Jiangsu Province China +86 25 84315941 +86 25 84303965 +86 25 84315941 +86 25 84303965
| | - Lianjun Wang
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology Nanjing 210094 Jiangsu Province China +86 25 84315941 +86 25 84303965 +86 25 84315941 +86 25 84303965
| | - Xiuyun Sun
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology Nanjing 210094 Jiangsu Province China +86 25 84315941 +86 25 84303965 +86 25 84315941 +86 25 84303965
| | - Jiansheng Li
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology Nanjing 210094 Jiangsu Province China +86 25 84315941 +86 25 84303965 +86 25 84315941 +86 25 84303965
| | - Xiaodong Liu
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology Nanjing 210094 Jiangsu Province China +86 25 84315941 +86 25 84303965 +86 25 84315941 +86 25 84303965
| | - Jinyou Shen
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology Nanjing 210094 Jiangsu Province China +86 25 84315941 +86 25 84303965 +86 25 84315941 +86 25 84303965
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Sun Y, Lei C, Khan E, Chen SS, Tsang DCW, Ok YS, Lin D, Feng Y, Li XD. Aging effects on chemical transformation and metal(loid) removal by entrapped nanoscale zero-valent iron for hydraulic fracturing wastewater treatment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 615:498-507. [PMID: 28988085 DOI: 10.1016/j.scitotenv.2017.09.332] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 09/30/2017] [Accepted: 09/30/2017] [Indexed: 06/07/2023]
Abstract
In this study, alginate and polyvinyl alcohol (PVA)-alginate entrapped nanoscale zero-valent iron (nZVI) was tested for structural evolution, chemical transformation, and metals/metalloids removal (Cu(II), Cr(VI), Zn(II), and As(V)) after 1-2month passivation in model saline wastewaters from hydraulic fracturing. X-ray diffraction analysis confirmed successful prevention of Fe0 corrosion by polymeric entrapment. Increasing ionic strength (I) from 0 to 4.10M (deionized water to Day-90 fracturing wastewater (FWW)) with prolonged aging time induced chemical instability of alginate due to dissociation of carboxyl groups and competition for hydrogen bonding with nZVI, which caused high Na (7.17%) and total organic carbon (24.6%) dissolution from PVA-alginate entrapped nZVI after 2-month immersion in Day-90 FWW. Compared to freshly-made beads, 2-month aging of PVA-alginate entrapped nZVI in Day-90 FWW promoted Cu(II) and Cr(VI) uptake in terms of the highest removal efficiency (84.2% and 70.8%), pseudo-second-order surface area-normalized rate coefficient ksa (2.09×10-1Lm-2h-1 and 1.84×10-1Lm-2h-1), and Fe dissolution after 8-h reaction (13.9% and 8.45%). However, the same conditions inhibited Zn(II) and As(V) sequestration in terms of the lowest removal efficiency (31.2% and 39.8%) by PVA-alginate nZVI and ksa (4.74×10-2Lm-2h-1 and 6.15×10-2Lm-2h-1) by alginate nZVI. The X-ray spectroscopic analysis and chemical speciation modelling demonstrated that the difference in metals/metalloids removal by entrapped nZVI after aging was attributed to distinctive removal mechanisms: (i) enhanced Cu(II) and Cr(VI) removal by nZVI reduction with accelerated electron transfer after pronounced dissolution of non-conductive polymeric immobilization matrix; (ii) suppressed Zn(II) and As(V) removal by nZVI adsorption due to restrained mass transfer after blockage of surface-active micropores. Entrapped nZVI was chemically fragile and should be properly stored and regularly replaced for good performance.
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Affiliation(s)
- Yuqing Sun
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Cheng Lei
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
| | - Eakalak Khan
- Department of Civil and Environmental Engineering, North Dakota State University, Dept 2470, P.O. Box 6050, Fargo, ND 58108, USA
| | - Season S Chen
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Daniel C W Tsang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
| | - Yong Sik Ok
- O-Jeong Eco-Resilience Institute (OJERI), Division of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Daohui Lin
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
| | - Yujie Feng
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Xiang-Dong Li
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
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