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Ma X, Liu X, Shang X, Zhao Y, Zhang Z, Lin C, He M, Ouyang W. Efficient roxarsone degradation by low-dose peroxymonosulfate with the activation of recycling iron-base composite material: Critical role of electron transfer. JOURNAL OF HAZARDOUS MATERIALS 2024; 469:134087. [PMID: 38518697 DOI: 10.1016/j.jhazmat.2024.134087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 03/06/2024] [Accepted: 03/18/2024] [Indexed: 03/24/2024]
Abstract
Pollutant degradation via electron transfer based on advanced oxidation processes (AOPs) provides an economical and energy-efficient method for pollution control. In this study, an iron-rich waste, heating pad waste (HPW), was recycled as a raw material, and a strong magnetic catalyst (Fe-HPW) was synthesized at high temperature (900 °C). Results showed that in the constructed Fe-HPW/PMS system, effective roxarsone (ROX) degradation and TOC removal (72.54%) were achieved at a low-dose of oxidant (PMS, 0.05 mM) and catalyst (Fe-HPW, 0.05 g L-1), the ratio of PMS to ROX was only 2.5:1. In addition, the released inorganic arsenic was effectively removed from the solution. The analysis of the experimental results showed that ROX was effectively degraded by forming PMS/catalyst surface complexes (Fe-HPW-PMS*) to mediate electron transfer in the Fe-HPW/PMS system. Besides, this system performed effective ROX degradation over a wide pH range (pH=3-9) and showed high resistance to different water parameters. Overall, this study not only provides a new direction for the recycling application of HPW but also re-emphasizes the neglected nonradical pathway in advanced oxidation processes.
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Affiliation(s)
- Xiaoyu Ma
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875
| | - Xitao Liu
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875.
| | - Xiao Shang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875
| | - Yanwei Zhao
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875
| | - Zhenguo Zhang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875
| | - Chunye Lin
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875
| | - Mengchang He
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875
| | - Wei Ouyang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875; Advanced Interdisciplinary Institute of Environment and Ecology, Beijing Normal University, Zhuhai 519087, China
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2
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Luo Z, Peng X, Liang W, Zhou D, Dang C, Cai W. Enhanced adsorption of roxarsone on iron-nitrogen co-doped biochar from peanut shell: Synthesis, performance and mechanism. BIORESOURCE TECHNOLOGY 2023; 388:129762. [PMID: 37716571 DOI: 10.1016/j.biortech.2023.129762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 09/04/2023] [Accepted: 09/09/2023] [Indexed: 09/18/2023]
Abstract
Efficient removal of organic arsenic (roxarsone, ROX) from wastewater is highly demanded on the purpose of human health and environmental protection. This work aims to prepare Fe-N co-doped biochar (Fe-N-BC) via one-pot hydrothermal method using waste peanut shell, FeCl3·6H2O and urea, followed by pyrolysis. The effect of Fe-N co-doping on biochar's physicochemical properties, and adsorption performance for ROX were systematically investigated. At the pyrolysis temperature of 650 °C, Fe-N-BC-650 shows a significantly increased specific surface area of 358.53 m2/g with well-developed micro-mesoporous structure. Its adsorption capacity for ROX reaches as high as 197.32 mg/g at 25 °C, with > 90 % regeneration efficiency after multiple adsorption-desorption cycles. Correlation and spectral analysis revealed that the pore filling, π-π interactions, as well as hydrogen bonding play the dominant role in ROX adsorption. These results suggest that the Fe-N co-doped biochar shows great potential in the ROX removal from wastewater with high efficiency.
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Affiliation(s)
- Zhijia Luo
- School of Chemistry and Chemical Engineering, Guangzhou University, 510006 Guangzhou, China; Joint Institute of Guangzhou University & Institute of Corrosion Science and Technology, Guangzhou University, Guangzhou, China
| | - Xiong Peng
- DeCarbon Tech. (Shenzhen) Co., Ltd, 518071 Shenzhen, China
| | - Wanwen Liang
- School of Chemistry and Chemical Engineering, Guangzhou University, 510006 Guangzhou, China; Joint Institute of Guangzhou University & Institute of Corrosion Science and Technology, Guangzhou University, Guangzhou, China.
| | - Dan Zhou
- School of Chemistry and Chemical Engineering, Guangzhou University, 510006 Guangzhou, China
| | - Chengxiong Dang
- School of Chemistry and Chemical Engineering, Guangzhou University, 510006 Guangzhou, China
| | - Weiquan Cai
- School of Chemistry and Chemical Engineering, Guangzhou University, 510006 Guangzhou, China.
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Lei M, Huang Y, Zhou Y, Mensah CO, Wei D, Li B. The role of organic and inorganic substituents of roxarsone determines its binding behavior and mechanisms onto nano-ferrihydrite colloidal particles. J Environ Sci (China) 2023; 129:30-44. [PMID: 36804240 DOI: 10.1016/j.jes.2022.09.035] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 09/23/2022] [Accepted: 09/25/2022] [Indexed: 06/18/2023]
Abstract
The retention and fate of Roxarsone (ROX) onto typical reactive soil minerals were crucial for evaluating its potential environmental risk. However, the behavior and molecular-level reaction mechanism of ROX and its substituents with iron (hydr)oxides remains unclear. Herein, the binding behavior of ROX on ferrihydrite (Fh) was investigated through batch experiments and in-situ ATR-FTIR techniques. Our results demonstrated that Fh is an effective geo-sorbent for the retention of ROX. The pseudo-second-order kinetic and the Langmuir model successfully described the sorption process. The driving force for the binding of ROX on Fh was ascribed to the chemical adsorption, and the rate-limiting step is simultaneously dominated by intraparticle and film diffusion. Isotherms results revealed that the sorption of ROX onto Fh appeared in uniformly distributed monolayer adsorption sites. The two-dimensional correlation spectroscopy and XPS results implied that the nitro, hydroxyl, and arsenate moiety of ROX molecules have participated in binding ROX onto Fh, signifying that the predominated mechanisms were attributed to the hydrogen bonding and surface complexation. Our results can help to better understand the ROX-mineral interactions at the molecular level and lay the foundation for exploring the degradation, transformation, and remediation technologies of ROX and structural analog pollutants in the environment.
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Affiliation(s)
- Ming Lei
- College of Resource & Environment, Hunan Agricultural University, Changsha 410128, China; Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha 410128, China; Key Laboratory of Southern Farmland Pollution Prevention and Control, Ministry of Agriculture, Changsha 410128, China
| | - Yayuan Huang
- College of Resource & Environment, Hunan Agricultural University, Changsha 410128, China; Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha 410128, China; Key Laboratory of Southern Farmland Pollution Prevention and Control, Ministry of Agriculture, Changsha 410128, China
| | - Yimin Zhou
- College of Resource & Environment, Hunan Agricultural University, Changsha 410128, China; Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha 410128, China; Key Laboratory of Southern Farmland Pollution Prevention and Control, Ministry of Agriculture, Changsha 410128, China
| | - Caleb Oppong Mensah
- College of Resource & Environment, Hunan Agricultural University, Changsha 410128, China; Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha 410128, China; Key Laboratory of Southern Farmland Pollution Prevention and Control, Ministry of Agriculture, Changsha 410128, China
| | - Dongning Wei
- College of Resource & Environment, Hunan Agricultural University, Changsha 410128, China; Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha 410128, China; Key Laboratory of Southern Farmland Pollution Prevention and Control, Ministry of Agriculture, Changsha 410128, China
| | - Bingyu Li
- College of Resource & Environment, Hunan Agricultural University, Changsha 410128, China; Hunan Engineering & Technology Research Center for Irrigation Water Purification, Changsha 410128, China; Key Laboratory of Southern Farmland Pollution Prevention and Control, Ministry of Agriculture, Changsha 410128, China.
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Li B, Wei D, Jing M, Zhou Y, Huang Y, Mensah CO, Long J, Tie B, Lei M. Nano-ferrihydrite colloidal particles mediated interfacial interactions of arsenate and cadmium: Implications for their fate under iron-rich geological settings. JOURNAL OF HAZARDOUS MATERIALS 2023; 447:130755. [PMID: 36640511 DOI: 10.1016/j.jhazmat.2023.130755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 01/01/2023] [Accepted: 01/06/2023] [Indexed: 06/17/2023]
Abstract
Arsenic (As) and cadmium (Cd) often coexist in paddy soils. Nano-ferrihydrite colloidal particles (NFPs) are ubiquitous at redox active interfaces of the paddy system and are well-known to play a critical role in controlling the solubility and bio-availability of As and Cd. However, the mutual interaction between As and Cd on NFPs remains elusive. Herein, batch experiments and in-situ spectroscopic techniques were used to investigate the effects of the interaction pattern (sequential reaction) of Cd(II) and As(V) on their respective adsorption on the surfaces of NFPs. Two scenarios were designed: Cd(II) pre-saturated NFPs and As(V) pre-saturated NFPs. Adsorption of Cd(II) was increased by 1.67, 4.08, and 5.21 times in As(V)-saturated NFPs, but only by 1.05, 1.11, and 1.15 times for As(V) in Cd(II)-saturated NFPs. Further, we determined the pH-dependent mutually beneficial cooperation pathways as mediated by the surface of NFPs. At lower pH (5), As(V) tended to promote Cd(II) adsorption, whereas Cd(II) tended to enhance As(V) adsorption at higher pH (> 5.5). X-ray photoelectron spectroscopy (XPS) indicated that both pre-saturated Cd(II) and As(V) altered the local coordination environment of their counterpart ions. Furthermore, results from in-situ attenuated total reflection-Fourier-transform infrared spectroscopy (ATR-FTIR) and second derivative peak shape fitting revealed two types of ternary surface complexes, namely Cd(II)-bridged and As(V)-bridged complexes, which were responsible for the distinct Cd(II) and As(V) co-adsorption behavior on the surface of NFPs under different conditions. These findings help us understand how co-presence Cd and As behave in an iron-rich geological setting and will aid in the development of related restoration technologies.
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Affiliation(s)
- Bingyu Li
- College of Resource and Environment, Hunan Agricultural University, Changsha 410128, PR China; Hunan Engineering and Technology Research Center for Irrigation Water Purification, Changsha 410128, PR China
| | - Dongning Wei
- College of Resource and Environment, Hunan Agricultural University, Changsha 410128, PR China
| | - Miaomiao Jing
- College of Resource and Environment, Hunan Agricultural University, Changsha 410128, PR China; Hunan Engineering and Technology Research Center for Irrigation Water Purification, Changsha 410128, PR China
| | - Yimin Zhou
- College of Resource and Environment, Hunan Agricultural University, Changsha 410128, PR China; Hunan Engineering and Technology Research Center for Irrigation Water Purification, Changsha 410128, PR China
| | - Yayuan Huang
- College of Resource and Environment, Hunan Agricultural University, Changsha 410128, PR China; Hunan Engineering and Technology Research Center for Irrigation Water Purification, Changsha 410128, PR China
| | - Caleb Oppong Mensah
- College of Resource and Environment, Hunan Agricultural University, Changsha 410128, PR China; Hunan Engineering and Technology Research Center for Irrigation Water Purification, Changsha 410128, PR China
| | - Jiumei Long
- College of Life Sciences and Environment, Hengyang Normal University, Hengyang 421008, PR China
| | - Boqing Tie
- College of Resource and Environment, Hunan Agricultural University, Changsha 410128, PR China; Hunan Engineering and Technology Research Center for Irrigation Water Purification, Changsha 410128, PR China
| | - Ming Lei
- College of Resource and Environment, Hunan Agricultural University, Changsha 410128, PR China; Hunan Engineering and Technology Research Center for Irrigation Water Purification, Changsha 410128, PR China.
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Wang H, Zhong D, Xu Y, Chang H, Shen H, Xu C, Mou J, Zhong N. Enhanced removal of Cr(VI) from aqueous solution by nano- zero-valent iron supported by KOH activated sludge-based biochar. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.129697] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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6
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Environmental Behavior and Remediation Methods of Roxarsone. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12157591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Roxarsone (ROX) is used extensively in the broiler chicken industry, and most is excreted in poultry litter. ROX degradation produces inorganic arsenic, which causes arsenic contamination of soil and aquatic environment. Furthermore, elevated arsenic concentrations are found in livers of chickens fed ROX. Microorganisms, light, and ions are the main factors that promote ROX degradation in the environment. The adsorption of ROX on different substances and its influencing factors have also been studied extensively. Additionally, the remediation method, combining adsorption and degradation, can effectively restore ROX contamination. Based on this, the review reports the ecological hazards, discussed the transformation and adsorption of ROX in environmental systems, documents the biological response to ROX, and summarizes the remediation methods of ROX contamination. Most previous studies of ROX have been focused on identifying the mechanisms involved under theoretical conditions, but more attention should be paid to the behavior of ROX under real environmental conditions, including the fate and transport of ROX in the real environment. ROX remediation methods at real contaminated sites should also be assessed and verified. The summary of previous studies on the environmental behavior and remediation methods of ROX is helpful for further research in the future.
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Xie X, Li J, Luo L, Liao W, Luo S. Phenylarsonics in concentrated animal feeding operations: Fate, associated risk, and treatment approaches. JOURNAL OF HAZARDOUS MATERIALS 2022; 430:128394. [PMID: 35158239 DOI: 10.1016/j.jhazmat.2022.128394] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 01/27/2022] [Accepted: 01/28/2022] [Indexed: 06/14/2023]
Abstract
Phenylarsonics are present as additives in animal feed in some countries. As only a small fraction of these additives is metabolized in animals, they mostly end up in the environment. A comprehensive investigation of the fate of these additives is crucial for evaluating their risks. This review aims to provide a clear understanding of the transformation mechanism of phenylarsonics in vivo and in vitro and to evaluate their fate and associated risks. Degradation of phenylarsonics releases toxic As species (mainly as inorganic arsenic (iAs)). Trivalent phenylarsonics are the metabolites or biotic degradation intermediates of phenylarsonics. The cleavage of As groups from trivalent phenylarsonics catalyzed by C-As lyase or other unknown pathways generates arsenite (As(III)). As(III) can be further oxidized to arsenate (As(V)) and methylated to methyl-arsenic species. The half-lives associated with abiotic degradation of phenylarsonics ranged from a few minutes to tens of hours, while those associated with biotic degradation ranged from several days to hundreds of days. Abiotic degradation resulted in a higher yield of iAs than biotic degradation. The use of phenylarsonics led to elevated total As and iAs levels in animal products and environmental matrices, resulting in As exposure risk to humans. The oxidation of phenylarsonics to As(V) facilitated the sorptive removal of As, which provides a general approach for treating these compounds. This review provides solid evidence that the use of phenylarsonics has adverse effects on both human health and environmental safety, and therefore, supports their withdrawal from the global market.
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Affiliation(s)
- Xiande Xie
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China
| | - Jingxia Li
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China
| | - Lin Luo
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China
| | - Wenjuan Liao
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China.
| | - Shuang Luo
- College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China.
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Liu L, Zhao J, Liu X, Bai S, Lin H, Wang D. Reduction and removal of As(Ⅴ) in aqueous solution by biochar derived from nano zero-valent-iron (nZVI) and sewage sludge. CHEMOSPHERE 2021; 277:130273. [PMID: 33770694 DOI: 10.1016/j.chemosphere.2021.130273] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 03/09/2021] [Accepted: 03/10/2021] [Indexed: 06/12/2023]
Abstract
Biochar prepared by co-pyrolysis of nano-zero-valent iron and sewage sludge (nZVISB) was used to remove As(Ⅴ) from aqueous solution. When the initial pH was 2, the initial As(Ⅴ) concentration was 20 mg L-1, the dose of nZVISB was 10 g L-1, the contact time was 24 h, and the adsorption temperature was 298K, the removal efficiency of As(Ⅴ) was greater than 99%. The isothermal removal of As(Ⅴ) followed the Freundlich model better, and the maximum adsorption capacity of As(Ⅴ) was 60.61 mg g-1. The removal process of As(Ⅴ) could be better described by pseudo-second-order kinetic model, and the rate-controlling step should be liquid film diffusion and chemical reaction. Thermodynamic analysis indicated that the removal of As(Ⅴ) was a spontaneous and endothermic process dominated by chemical adsorption. The characterizations of nZVISB before/after adsorption and the solution after adsorption suggested that the iron-containing substances (Fe0, Fe2+, FeOOH) and organics in the nZVISB had a great effect on the removal of As(Ⅴ), and the As was mainly immobilized on nZVISB by speciation of As-O-Fe.
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Affiliation(s)
- Liheng Liu
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China; Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin, 541004, China
| | - Jirong Zhao
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China
| | - Xiu Liu
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China
| | - Shaoyuan Bai
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China; Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin, 541004, China
| | - Hua Lin
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China; Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin, 541004, China.
| | - Dunqiu Wang
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China; Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin, 541004, China
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Chen C, Liu L, Li Y, Zhou L, Lan Y. Efficient degradation of roxarsone and simultaneous in-situ adsorption of secondary inorganic arsenic by a combination of Co 3O 4-Y 2O 3 and peroxymonosulfate. JOURNAL OF HAZARDOUS MATERIALS 2021; 407:124559. [PMID: 33341568 DOI: 10.1016/j.jhazmat.2020.124559] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 11/10/2020] [Accepted: 11/10/2020] [Indexed: 06/12/2023]
Abstract
Roxarsone (ROX), as one of aromatic organoarsenic compounds (AOCs), is extensively used in livestock industry, which tends to transform into high-toxic inorganic arsenic in environments. Herein, a bifunctional Co3O4-Y2O3, possessing extremely excellent catalytic and adsorption performance due to the synergy of Co3O4 and Y2O3, was designed and employed to activate peroxymonosulfate (PMS) for the elimination of ROX and the simultaneous in-situ adsorption of secondary inorganic arsenic, in which Co3O4 acted as the primary catalyst, and Y2O3 served as the main adsorbent. 50 μM (3.75 mg-As/L) of ROX was almost completely degraded, coupled with the conversion of As(III) to As(V) in the system of Co3O4-Y2O3 (0.2 g/L) and PMS (0.5 mM) within 15 min at initial pH 7. Meanwhile, > 99.3% of the secondary As(V) would be removed within 120 min. The reactive oxygen species (ROS) were identified to be •OH, SO4•-, and 1O2, which were responsible for the ROX degradation and the formation of As(V). Simultaneously, the produced As(V) were effectively adsorbed via the ligand/anion exchange with surface -OH and CO32- anions of Co3O4-Y2O3. The possible degradation pathways of ROX were further proposed on the basis of the intermediates identification. Our findings may provide an insight into the degradation of AOCs and the simultaneous removal of secondary inorganic arsenic via the PMS activation with Co3O4-Y2O3.
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Affiliation(s)
- Cheng Chen
- College of Sciences, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Li Liu
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Yuxin Li
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Lixiang Zhou
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Yeqing Lan
- College of Sciences, Nanjing Agricultural University, Nanjing 210095, PR China.
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Ma F, Philippe B, Zhao B, Diao J, Li J. Simultaneous adsorption and reduction of hexavalent chromium on biochar-supported nanoscale zero-valent iron (nZVI) in aqueous solution. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2020; 82:1339-1349. [PMID: 33079714 DOI: 10.2166/wst.2020.392] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Flax straw biochar (FSBC)-supported nanoscale zero-valent iron (nZVI) composite (nZVI-FSBC) combining the advantages of nZVI and biochar was synthesized and tested for Cr(VI) removal efficiency from aqueous solution. Surface morphology and structure of FSBC and nZVI-FSBC were characterized by scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller techniques, which help to clarify the mechanism of Cr(VI) removal from aqueous solution. The adsorption of Cr(VI) onto FSBC and nZVI-FSBC was best described by the pseudo-second-order and the Sips model. Compared with FSBC, nZVI-FSBC remarkably improved the performance in removing Cr(VI) under identical experimental conditions. Due to the collaborative effect of adsorption and reduction of nZVI-FSBC, the adsorption capacity of nZVI-FSBC for Cr(VI) is up to 186.99 mg/g. The results obtained by XPS, XRD, and FTIR confirmed that adsorption and reduction dominated the processes of Cr(VI) removal by nZVI-FSBC. As a supporter, FSBC not only improved the dispersion of nZVI, but also undertook the adsorption task of Cr(VI) removal. The surface oxygen-containing functional groups of nZVI-FSBC mainly participated in the adsorption part, and the nZVI promoted the Cr(VI) removal through the redox reactions. These observations indicated that the nZVI-FSBC can be considered as potential adsorbents to remove Cr(VI) for environment remediation.
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Affiliation(s)
- Fengfeng Ma
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China E-mail: ;
| | - Bakunzibake Philippe
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China E-mail: ;
| | - Baowei Zhao
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China E-mail: ;
| | - Jingru Diao
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China E-mail: ;
| | - Jian Li
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China E-mail: ;
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