APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
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IF 20.2
Jianxin Zhu,Haiyang Liu,Haijun Chen,Xiuyi Hua,Deming Dong,Dapeng Liang,Zhiyong Guo,Na Zheng
Low degradation efficiency and significant transition metal leaching are two challenges in persulfate activation systems based on metal-organic frameworks (MOFs) for organic pollutant degradation. Here, the challenges were solved by designing and synthesizing a micron-sized core-shell material, γ-Al 2 O 3 -C-MIL-100(Fe) (γACM), by coating the γ-Al 2 O 3 core with carbon (γ-Al 2 O 3 -C) and futher modifying with MIL-100(Fe). Testing γACM with sulfamethazine (SMZ) demonstrated its outstanding peroxydisulfate (PDS) activation, achieving 92.5 % SMZ removal within 20 min at a low oxidant/pollutant ratio. Fe leaching from γACM was effectively inhibited, with only 3.59 % Fe lost after three recycles. The system showed adaptability across a wide pH range, and usability in sewage effluent, indicating promise for practical application. The hydrophobicity of γ-Al 2 O 3 -C, the coordinatively unsaturated sites in MIL-100(Fe), and the strong bounding of MIL-100(Fe) on γ-Al 2 O 3 -C ensured the effective SMZ gather, PDS activation, and Fe stability respectively, which led to the excellent performances of γACM.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2020
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IF 10.652
Yangke Long,Shun Li,Yiping Su,Shuyang Wang,Shiyin Zhao,Shubin Wang,Zhen Zhang,Wei Huang,Yong Liu,Zuotai Zhang
The poor performance and severe metal leaching of iron-based Fenton-like catalysts during reaction are the main bottlenecks that suppress their practical applications. Herein, a well-defined structure was achieved by confining catalytically active but unstable sulfur-containing iron species within S/N co-doped porous carbon (Fe-S@SNC) through a simple pyrolysis route. The hierarchically porous and highly conductive carbon host not only provided abundant exposed active sites and fast mass/electron-transfer, but also prohibited the aggregation of iron composites during catalysis. The synergistic effects of confined iron nano-composites and heteroatoms (S/N) significantly elevated the activation of peroxymonosulfate (PMS). As a result, the Fe-S@SNC/PMS system exhibited excellent catalytic degradation performance for various contaminants including dyes, phenolic compounds, and antibiotics. Importantly, a low iron leaching was detected during usage due to the nano-confinement effect of carbon layers, and therefore solves the long-term issue of secondary pollution caused by metal leaching. Furthermore, the underlying degradation mechanism of Fe-S@SNC/PMS system was systematically investigated by radical quenching tests, EPR analysis, and chronoamperometry experiments. It was found that the superoxide anion radical (O 2 − ) was the predominant free radicals that contributed to the radical oxidation of organic pollutants, while the electron transfer mediation on Fe-S@SNC resulted in the non-radical oxidation. Additionally, the LC-MS results coupled with time-dependent HPLC spectra validated that the degradation efficiency and intermediate products were significantly dependent on solution pH and background species. This work provides new insight into the design and activation mechanism of iron-based PMS activators.
研究领域:
环境科学
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催化材料
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DOI
高影响因子
ELECTROCHIMICA ACTA
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2022
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IF 7.336
Fengyue Zhao,Juan Xiao,Shipeng Geng,Yi Wang,Panagiotis Tsiakaras,Shuqin Song
Fe 3+ /Fe 2+ interconversion is one of the key factors for heterogeneous electro-Fenton degradation of organic pollutants. In this study, MIL-101Fe-derived carbon wrapping Fe 7 S 8 nanocomposite (Fe 7 S 8 /C-1-600) exhibits outstanding rhodamine B (RhB) degradation ability with extremely low iron leaching and high recyclable degradability within 60 min in a wide pH range. Moreover, Fe 7 S 8 /C-1-600 presents a much higher activity for RhB degradation than Fe 3 O 4 counterpart without sulfidation, which could be mainly attributed to the accelerated Fe 3+ /Fe 2+ cycling by iron with both multiple valences (Fe 0 , Fe 2+ , and Fe 3+ ) and sulfur species (S 2− and S 2 2− ) of the catalyst. The enhancement of H 2 O 2 adsorption and activation into OH on Fe 7 S 8 surface is confirmed by density functional theory calculations with respect to that on Fe 3 O 4 . Interestingly, SO 4 · − can be generated by reacting S 2 2− with dissolved O 2 and subsequently converted into ·OH, which further facilitates RhB degradation. These findings may shed a new insight into the potential application of metal sulfides for wastewater treatment.
研究领域:
环境科学
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化学工程
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材料科学
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水处理
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
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IF 7.312
Xixi Wu,Teng Li,Ruizi Wang,Yixuan Zhang,Wenzhe Liu,Liangjie Yuan
In this work, zero-valent iron particles supported on nitrogen doped porous carbon (Fe-NPC) was successfully prepared by a green and convenient one-pot method through pyrolysis. In Fe-NPC/PS system, 96.44% orange II (OGII) was almost removed within 35 min, which was much higher than NPC and Fe-PC of 53.27% and 54.67%, respectively. Factors influencing the degradation process of OGII were investigated, including PS concentration, catalyst dosage, initial pH and ions disturbance. The radical quenching studies, electron paramagnetic resonance (EPR) measurements and chronoamperometry experiments verified the degradation mechanism of OGII in Fe-NPC/PS system included both radical and non-radical pathways in which • HO and SO 4 -· were the dominant active radicals and electron transfer was involved. Fe-NPC exhibited excellent tolerance toward a wide pH conditions with only 88 µg/L iron leaching in initial pH of 3.1, which was much lower than literature reported. The low iron leaching of Fe-NPC was attributed to the protection of carbon matrix and doped nitrogen in catalyst. Moreover, the surface C O group of the catalyst contributed to better performance in alkaline system. Furthermore, the supported iron species introduced magnetism into the catalyst for easily separation. The Fe-NPC/PS system also exhibited high removal efficiencies for Congo red (CR), Reactive blue 19 (RB 19), 4-Nitrophenol (4-NP) and tetracycline (TC). These results provided a sight for economically and efficiently fabricating stable iron based nitrogen doped porous carbon catalyst for water contaminant degradation.
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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水处理
✓ 已验证
产品关联
DOI
高影响因子