Water
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2022
·Vol. 14
·期 9
·1420
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IF 3.53
Juan Peng,Yameng Ma,Xiao Huang,Jianghua Yu,Fengjiao Yu,Jingsi Gao
Ni-ethylenediaminetetraacetic acid (Ni-EDTA) poses serious threats to the ecological environment and human health, due to its acute toxicity and low biodegradability. The decomplexation efficiency of Ni-EDTA through the conventional Fenton process has been constrained to pH; thus, other appropriate approaches are required to destroy the stable chelate structure at a neutral pH. In this study, the effect of operating parameters such as the pH, Fe2+concentration, particle electrode dosage, current density, and coexisting ions was studied. The results revealed that the 3D-EF system owned advantages for the removal of Ni-EDTA in the broadening of the pH application window. The Ni-EDTA removal efficiency in the 3D-EF system reached 84.89% after 120 min at a pH of 7. In addition, the presence of coexisting ions slightly affected the decomplexation efficiency of Ni-EDTA.Keywords:Ni-EDTA;three-dimensional electro-Fenton;neutral pH;decomplexation
研究领域:
环境科学
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化学工程
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
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IF 12.2
Li-Zhi Huang,Junpeng Li,Weiguo Chen,Jia Deng,Fang Zhang
Ni organic complexes are widely used in industrial production, posing severe threats to the natural environment and human health. In this work, we found that Ni (0) formed by the decomplexation and reduction of typical Ni organic complexes (Ni-EDTA) on the surface of carbon felt cathode. The formed Ni(0) as a catalytic site generates atomic hydrogen (H•) with strong reductive reactivity via electron transfer. H• not only accelerates the oxygen activation to form H 2 O 2 on carbon felt cathode, but also reacts with H 2 O 2 to generate strong oxidative hydroxyl radicals (HO•) and singlet oxygen ( 1 O 2 ). Under the attack of multiple active species, 95.5 % of Ni-EDTA is removed, and the removal efficiencies of total organic carbon (TOC) and dissolved Ni reach 43.8 % and 77.1 % after 120 min of electrolysis at −2.0 V (vs. Ag/AgCl). The redox synergistic reaction, initiated by the formation of Ni(0) on the carbon felt cathode, demonstrates excellent stability in treating real Ni plating wastewater. This approach eliminates the need for additional chemical reagents and prevents the release of heavy metals. Our findings offer a novel strategy for leveraging the self-transformation of Ni organic complexes to generate various active species for electrochemical treatment of Ni plating wastewater.
研究领域:
环境科学
·
电化学
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PubMed
高影响因子
WATER RESEARCH
·
2022
·
IF 13.4
Haolin Xu,Rundong Chen,Sheng Liang,Zhenchao Lei,Wenxiao Zheng,Zhang Yan,Jianxin Cao,Chaohai Wei,Chunhua Feng
The formation of chlorinated byproducts represents a significant threat to the quality of the effluent treated using electrochemical advanced oxidation processes (EAOPs), thus spurring investigation into alleviating their production. This study presents a new strategy to minimize the release of chlorinated intermediates during the electrochemical oxidation of Ni-EDTA by establishing a dual mixed metal oxide (MMO)/Fe anode system. The results indicate that the dual-anode system achieved a substantially higher rate (0.141 min − 1 ) of Ni-EDTA destruction and accordingly allowed a more pronounced removal of aqueous Ni (from 39.85 to 0.63 mg L − 1 ) after alkaline precipitation, compared with its single MMO anode (0.017 min − 1 of Ni-EDTA removal, with 14.38 mg L − 1 Ni remaining) and single Fe anode (insignificant Ni-EDTA removal, with 38.37 mg L − 1 Ni remaining) counterparts. Compared to reactive chlorine species (RCS) produced from the single MMO anode system, Fe(IV) was in situ generated from the dual-anode system and was predominantly responsible for the attenuation of chlorinated byproducts and thus the decrease in the acute toxicity of the treated solution (evaluated using luminescent bacteria). The Fe(IV)-dominated dual-anode system also exhibited superior performance in removing multiple pollutants (including organic ligands, Ni, and phosphite) in the real electroless plating effluent. The findings suggest that the strategy for Fe(II) transition to Fe(IV) by active chlorine paves a new avenue for yielding less chlorinated products with lower toxicity when EAOPs are used to treat chloride-containing organic wastewater.
研究领域:
环境科学
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电化学工程
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DOI
PubMed
高影响因子
CHEMOSPHERE
·
2018
·
IF 4.427
Zilong Zhao,Zekun Liu,Hongjie Wang,Wenyi Dong,Wei Wang
Treatment of Ni-EDTA in industrial nickel plating effluents was investigated by integrated application of Fenton and ozone-based oxidation processes. Determination of integrated sequence found that Fenton oxidation presented higher apparent kinetic rate constant of Ni-EDTA oxidation and capacity for contamination load than ozone-based oxidation process, the latter, however, was favorable to guarantee the further mineralization of organic substances, especially at a low concentration. Serial-connection mode of two oxidation processes was appraised, Fenton effluent after treated by hydroxide precipitation and filtration negatively affected the overall performance of the sequential system, as evidenced by the removal efficiencies of Ni 2+ and TOC dropping from 99.8% to 98.7%, and from 74.8% to 66.6%, respectively. As a comparison, O 3 /Fe 2+ oxidation process was proved to be more effective than other processes (e.g. O 3 -Fe 2+ , O 3 /H 2 O 2 /Fe 2+ , O 3 /H 2 O 2 -Fe 2+ ), and the final effluent Ni 2+ concentration could satisfied the discharge standard (<0.1 mg L −1 , China) under the optimal conditions (H 2 O 2 dosage of 1.0 mL L −1 , Fe 2+ : H 2 O 2 mole ratio of 1.46, and reaction time of 10 min for Fenton reaction , initial influent pH of 3.0, O 3 dosage of 252 mg L −1 , Fe 2+ of 150 mg L −1 , and reaction time of 30 min for O 3 /Fe 2+ oxidation). Furthermore, pilot-scale test was carried out to study the practical treatability towards the real nickel plating effluent, revealing the effective removal of some other co-existence contaminations. And Fenton reaction has contributed most, with the percentage ranging from 72.41% to 93.76%. The economic cost advantage made it a promising alternative to the continuous Fenton oxidation.
研究领域:
环境科学
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化学工程
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PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2017
·
IF 4.798
Lianghao Li,Zhuangpeng Huang,Xiaoxiao Fan,Zhen Zhang,Rongni Dou,Shulong Wen,Yuan Chen,Yuancai Chen,Yongyou Hu
An optimized metal oxide electrode (Ti/SnO 2 -Sb-Pd) was prepared via thermal decomposition and used in the electrochemical degradation of Ni-EDTA. The electrode was characterized by SEM, XRD, XPS, and electrochemical characterizations including linear-sweep voltammetry (LSV), cyclic voltammetry (CV) and chronopotentiometry (CP) techniques. It was found that Pd doping could effectively change the surface morphology and lattice parameters of the metal oxide electrode. Pd can facilitate the entry of more Sb into SnO 2 crystals and promote the reduction of Sb from the +5 to the +3 state. The interaction of these metals raised the oxygen evolution potential (OEP) and electrochemical surface area of the electrode, in addition to reducing the degradation potential and increasing the degradation current of Ni-EDTA. When the molar ratio of Pd:Sn was 2.5%, the electrode could simultaneously degrade 87.5% of Ni-EDTA and recycle 17.9% of elemental Ni on the cathode within 120 min. At the same time, with Pd doping, the lifetime of the electrode was increased more than 40 times, demonstrating good potential for application in industry.
研究领域:
材料科学
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环境工程
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ENVIRONMENTAL TECHNOLOGY
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2023
·
IF 2.8
Wenyan Wang,Yunlan Xu,Dengjie Zhong
Ni-EDTA is widely present in electroplating effluents. It cannot be effectively removed by traditional wastewater treatment methods due to its chemical stability. In this study, copper sulphide/cuprous sulphide doped zero-valent iron@carbon (ZVI@C/CuS/Cu2S) was prepared to active peroxymonsulphate (PMS) to decomposition Ni-EDTA. The ZVI@C/CuS/Cu2S + PMS process shows excellent performance under neutral or even alkaline conditions. This is due to the acceleration of ZVI electron transport by CuS/Cu2S, the autocatalysis of CuS/Cu2S itself, and the synergistic effect of CuS/Cu2S and Ni-EDTA. The removal efficiency of 50 ppm Ni-EDTA electroplating effluents reached 99.53% at 10 min, and the discharge water can meet the Chinese emission standard. The influences of the main parameters such as initial pH value, catalyst, PMS and initial Ni-EDTA concentration on removal efficiency was systematically investigated.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Shuyu Qi,Zilong Zhao,Yingqing Ou,Lu Liu,Yatao Ren,Wenyi Dong,Hongjie Wang,Zigong Ning
In this study, a calcium-rich biochar (CRB)-enhanced dual reaction center (DRC) Fenton-like catalyst, Cu-Al 2 O 3 -CRB, was synthesized for the decomplexation of a typical heavy metal complex pollutant, Ni-ethylenediaminetetraacetic acid (Ni-EDTA), in industrial wastewater. After a 90-minute reaction, the removal rate of Ni(II) could reach 95.2%, regardless of the initial solution pH. Various characterization analyses confirmed the formation of electron-rich Cu regions and electron-deficient Al and C regions in the Cu-Al 2 O 3 -CRB catalyst. The catalytic oxidation experiments, chronoamperometry tests, and reactive oxygen species (ROSs) detection further revealed the roles of biochar and CaCO 3 on the catalytic behavior of Cu-Al 2 O 3 -CRB catalyst. The presence of biochar not only enhanced the loading of Cu species but also introduced additional electron transfer channels, while CaCO 3 further interacted with biochar/Cu species to amplify the electron cloud density surrounding Cu. The improvement of electronic polarization facilitated the activation of H 2 O 2 and the generation of •O 2 – , 1 O 2 and •OH. Contrary to conventional interfacial reactions, the weak adsorption between Cu-Al 2 O 3 -CRB and Ni-EDTA due to the electrostatic repulsion, led to the decomplexation reactions primarily occurring in the solution phase, rather than on the catalyst surface. This study sheds light on the potential of Cu-Al 2 O 3 -CRB as a DRC catalyst and emphasizes the significance of contaminant properties when using this kind of catalysts.
研究领域:
环境科学
·
催化化学
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高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Meiling Chen,Lei Zhou,Xiuqin Xiong,Shijun Zhu,Xinkai Yuan,Boyin Yan,Bingrui Ma,Jiachuang Shao,Liming Yang,Xubiao Luo,Penghui Shao
Conventional advanced oxidation processes were used to treat heavy metal complexes. However, a considerable amount of oxidants was required to enable effective oxidative degradation, which led to a significant increase of the treatment costs and subsequent difficulties in the sludge disposal. Based on the abundance of anions in heavy metal wastewater, the effects of anions on the in-situ degradation of Ni-EDTA in an oxidant-free electrochemical system with boron-doped diamond (BDD) as the anode were investigated. The presence of Cl - was found to exert a significant effect on improving the degradation process. Moreover, pH had little effect on the removal of nickel (Ni) and Ni-EDTA within a specific pH range (1 < pH < 9). The removal efficiencies of Ni and TOC reached 100 % and 77.45 %, respectively, at pH 2.16 with 0.4 M NaCl electrolyte, 2 mM Ni-EDTA concentration, and a current density of 50 mA/cm 2 . •OH and Cl• played crucial roles in the removal of Ni-EDTA by disrupting the chelation sites of Ni and EDTA molecules. The released Ni 2+ ions could active the H 2 O 2 in-situ generated at the cathode to produce •OH. The formation of the precipitation products such as NiOOH, Ni(OH) 2 , and NiCO 3 in the Cl - /BDD system were conform based on the XRD and XPS analyses, which suggested the possible pathways for the removal of Ni 2+ and Ni 3+ . Finally, the possible degradation pathways of Ni-EDTA were proposed based on the identification of intermediate products using UPLC-MS.
研究领域:
环境科学
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电化学工程
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DOI
高影响因子
CHEMOSPHERE
·
2023
·
IF 8.8
Zilong Zhao,Shuyu Qi,Jianli Zhou,Yatao Ren,Kaiyun Zheng,Jin Zhang,Wenyi Dong,Hongjie Wang
To enhance the polarization distribution of electron cloud density on the catalyst surface, we have introduced a novel bimetallic-substituted dual-reaction center (DRC) catalyst (FeCo-γ-Al 2 O 3 ) comprising iron (Fe) and cobalt (Co) for the decomplexation and mineralization of heavy metal complex Ni-EDTA in this study. Compared to the catalysts doped solely with Fe or Co, the bimetal-doped catalyst offered several advantages, including enhanced electron cloud polarization distribution, additional electron transfer pathway, and improved capacity of free radical generation. Through DFT calculations and EPR tests, we have elucidated the influences of the catalyst's adsorption toward Ni-EDTA and its decomplexation products on the electron transfer between the pollutant and the catalyst. The competition between the pollutants and H 2 O 2 affects the generation of free radicals in both electron-rich Fe and Co centers as well as electron-deficient Al center. Building on these findings, we have proposed a plausible removal mechanism of Ni-EDTA using the heterogeneous Fenton-like catalyst FeCo-γ-Al 2 O 3 . This study sheds light on the potential of FeCo-γ-Al 2 O 3 as a DRC catalyst and emphasizes the significance of pollutant characteristics in determining the catalyst's performance.
研究领域:
环境科学
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材料科学
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化学工程
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Zilong Zhao,Yatao Ren,Shuyu Qi,Zigong Ning,Xing Wang,Wenyi Dong,Hongjie Wang
Heavy metal complexes pose a challenge in terms of their resistance to removal due to their stable and intricate structure. In this study, we explored the utilization of Fe and N co-doped biochar derived from rice husk (Fe-N-RHBC) as catalytic particle electrodes in a three-dimensional electro-Fenton (3D-EF) system for the decomplexation and removal of a model pollutant, Ni-EDTA. The characterization analysis and comparison of catalytic activities confirmed the beneficial effects of Fe and N co-doping on various aspects, such as the types of active sites, interfacial electron transfer properties, and H 2 O 2 decomposition capacity. Compared to other investigated oxidation systems, the 3D-EF process demonstrated rapid removal of Ni-EDTA within the initial minute, with a maximum H 2 O 2 utilization of 99.1% after 30 min. The prepared catalytic particle electrodes exhibited high stability and catalytic capacity even after three consecutive cycles. Throughout the reaction, several processes, including anode oxidation, particle electrode polarization, catalysis, and adsorption of Fe-N-RHBC, as well as cathodic electro-deposition, synergistically contributed to the treatment of Ni-EDTA. The surface-bound O 2 − radicals and 1 O 2 generated by the Fe-N-RHBC catalytic particle electrode played a crucial role in the decomplexation and removal of Ni-EDTA. Building upon these findings, we further proposed potential mechanisms for the removal of Ni-EDTA in the 3D-EF system using the Fe-N-RHBC catalytic particle electrode.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Meiling Chen,Lin Ding,Shijun Zhu,Xiuqin Xiong,Xinkai Yuan,Yanhua Peng,Liming Yang,Hui Shi,Penghui Shao,Xubiao Luo
The slow Fe(II)/Fe(III) cycle during the Fenton reaction process strongly impedes oxidation efficiency in practical applications. In this study, an activated carbon (AC) assisted Fenton reaction system was used to treat electroplating wastewater containing Ni-ethylenediaminetetraacetic acid (Ni-EDTA). AC was found to enhance the removal of Ni-EDTA in Fenton/Fenton-like reactions. The reported results revealed that AC could effectively promote the regeneration of Fe(II) from Fe(III) species via electron transfer to improve the reaction rather than directly enhancing the H 2 O 2 decomposition to accelerate the production of hydroxyl radicals (•OH). Quenching experiments and EPR also demonstrated that •OH and •O 2 − took part in the radical oxidation process, in which the contribution of •OH was dominant. XPS and FT-IR analysis further confirmed that the carbonyl group (C O) on the surface of AC could indeed act as the dominant active site and an electron donor to directly reduce Fe(III). In addition, electrochemical tests indicated that AC could increase the oxidation potential of Fe(III) to boost the reaction between Fe(III) and H 2 O 2 , thus enabling the transfer of electrons from H 2 O 2 to Fe(III) to facilitate the Fe(II)/Fe(III) cycle. This study might contribute to a new insight into the mechanisms of AC-catalyzed Fenton oxidation processes for the decomplexation heavy metal-EDTA.
研究领域:
环境科学
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化学工程
·
废水处理
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高影响因子
ACS ES&T Water
·
2023
·
IF 5.3
Ming Liu,Hua Zou,Penghui Shao,Hao Jia,Guoshuai Liu
The presence of metals and complexing agents in wastewater poses serious threats to public health and aquatic ecosystems. Electrochemically advanced oxidation processes can break down heavy metal compounds, but recovering these metals at the cathode presents challenges. To address this concern, we explore amidoxime, known for its high complexation capacity and hydrophilicity, as a cathodic microenvironment modifier to enhance heavy metal adsorption and immobilization. We develop a novel carbon felt (CF) amidoxime-functionalized group (CFAG) cathode for cathodic nickel recovery from Ni–EDTA. Experimental results show a significant improvement in nickel recovery efficiency with amidoxime functionalization. Specifically, CFAG outperforms CF by 2 times, driven by nickel recovery reaction kinetic constants of 0.0202 min–1 for CFAG and 0.0101 min–1 for CF. Furthermore, cycling and desorption experimental results have validated the enduring stability and regenerative attributes of the CFAG electrode, and the density functional theory calculations confirm that nickel binds more effectively to amidoxime groups than conventional polymer groups on CF. This study presents a promising electrochemical approach for recycling metals in complex heavy metal wastewater, making metal resource recovery more economical and efficient.
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高影响因子