Journal of Environmental Chemical Engineering
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2024
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IF 7.4
Yuzhu Xue,Weinan Wang,Yanhong Zhang,Qinhua Fan,Ying Zhang,Chen Ling,Yuwei Pan
This study proposes a green purification strategy in which mild decomplexation of Ni-EDTA into other Ni complexes facilitates the efficient removal and recovery of nickel through resin adsorption. Decomplexation of Ni-EDTA by boron/Fe 2+ /H 2 O 2 (B/Fe 2+ /H 2 O 2 ) followed by resins adsorption was conducted for Ni(II) removal in Ni-EDTA. The Ni(II) removal efficiency could only achieve 1.3 % and 6.2 % while Ni(II) coexisted with EDTA but more than 10 times of higher when Ni(II) coexisted with EDTA-relatives via the single adsorption of commercial heavy metal-affined resins (D001 and D463), which attributed to the increased binding energies of these Ni-EDTA’s degradation products complexes than Ni-EDTA based on density functional theory (DFT) calculation. In comparing to precipitation, the resin adsorption required much less mineralization of EDTA to have a better removal efficiency of Ni(II). B improved the efficiency of Ni-EDTA decompexation by accelerating the recycle of Fe 3+ /Fe 2+ . The EDTA (and TOC) removal enhanced from 48.7 % (4.7 %) to 94.7 % (11.9 %) by B/Fe 2+ /H 2 O 2 process comparing to Fe 2+ /H 2 O 2 process. With the high EDTA but low TOC removal efficiency after B/Fe 2+ /H 2 O 2 treatment, Ni(II) removal efficiency via resins adsorption could maximum achieve 80.5 %, 2–3 times of that via regular precipitation method. In addition, B and resins exhibited good reusability in five cycles, and B/Fe 2+ /H 2 O 2 -resins process had excellent adaptability to different heavy metal complexes. B/Fe 2+ /H 2 O 2 -D463 system not only could reduce 78.4 % reagents cost compared with that of Fe 2+ /H 2 O 2 -precipitation process, but also could save much cost than other processes. The results provide new insights for the cost-effective treatment of EDTA-complexed heavy metal wastewater.
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
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
·
IF 8.1
Zhen Huang,Ziyang Chu,Haibo Liu,Tianhu Chen,Xuehua Zou,Fuwei Sun,Dong Chen
Effective removal of heavy metal complexes from contaminated water remains a challenging task. In this work, a limestone/PMS system was constructed for the efficient degradation of Cu-EDTA. Under the conditions of 3.0 g/L limestone and 1.0 mM PMS, the degradation efficiency of 10.0 mg/L Cu-EDTA reached 99.0 % in 60 min, and the removal efficiency of Cu ions approached 50.0 %. The main active specie revealed by quenching and EPR experiments was the singlet oxygen ( 1 O 2 ). Interestingly, Trace amounts of Cu(II) in limestone react with PMS enhancing the degradation of Cu-EDTA. The results of the HPLC-MS analysis showed that the reactive species attacked the Cu–O and Cu–N bonds, as well as triggered a decarboxylation process, resulting in the decomposition of Cu-EDTA into six intermediates. Meanwhile, SEM and XPS analyses revealed that Cu ions released during the degradation of Cu-EDTA are deposited on the limestone surface as Cu(OH) 2 and Cu 2 (OH) 2 CO 3 . In addition, the initial pH and co-existing ions have a weak effect on the system. Finally, a one-month continuous flow experiment showed that the degradation efficiency of Cu-EDTA was about 95.0 % and the removal efficiency of Cu ions was 40.0 %. In conclusion, this study provides a new approach for the destruction of metal complexes and the removal of heavy metals.
研究领域:
环境科学
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化学
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DOI
高影响因子
ELECTROCHIMICA ACTA
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2017
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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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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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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
WATER SCIENCE AND TECHNOLOGY
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2022
·Vol. 87
·期 2
·492-507
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IF 2.43
Jiang Yu,Liu Xinyu,Huang Shikai,Wu Huifang,Liu Haiyan,Liu Shenzhe,Xu Jiale,Wang Kun
In this study, magnetic biochar (Fe-BC) was synthesized from phoenix tree leaves and FeSO 4 ·7H 2 O by impregnation-pyrolysis method, and was used to activate H 2 O 2 to degrade Cu-EDTA. The effects of preparation parameters on the degradation of Cu-EDTA by Fe-BC/H 2 O 2 system were investigated by degradation experiments and characterization methods (SEM, BET, FTIR, XRD and XPS). The results showed that the magnetic biochar prepared under the pyrolysis temperature of 400 °C, pyrolysis time of 3 h and iron content of 3 wt% had the best catalytic activity. Within 120 min, the breaking efficiency of Cu-EDTA binding, precipitation efficiency of Cu 2+ and removal efficiency of TOC could reach 78.48, 71.65 and 46.54% at the conditions of adding 1.0 g/L magnetic biochar and 25 mM H 2 O 2 and the iron dissolution was only 0.32 mg/L. The characterization results and comparison experiments demonstrated that the catalytic effect of magnetic biochar not only depends on the transfer of electrons to H 2 O 2 by the loaded iron oxides, but also the active oxygen functional groups (OFGs) and persistent free radicals (PFRs) contained on the surface can transfer electrons to H 2 O 2 or even dissolved oxygen to produce an amount of hydroxyl radicals ( · OH) and superoxide anion radicals ( ). The use of phoenix tree leaves as the precursor of magnetic biochar provides a new method for the disposal of garden waste, which is in accord with the concept of green and sustainable development. In the degradation system, the magnetic biochar catalyst relies on the OFGs and PFRs of biochar and the metal components loaded to activate H 2 O 2 to generate reactive oxygen species to degrade organic pollutants.
研究领域:
环境化学
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环境功能材料
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污染控制化学
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高级氧化技术
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废弃物资源化利用
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DOI
高影响因子
危险品化学品经营许可证（带存储）