• Title/Summary/Keyword: Fenton-like reaction

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Oxidative Degradation of Phenol Using Zero-Valent Iron-Based Fenton-Like Systems (영가철 기반 펜톤 시스템을 활용한 페놀의 산화분해)

  • Kim, Hak-Hyeon;Lee, Hye-Jin;Kim, Hyung-Eun;Lee, Hongshin;Lee, Byeong-Dae;Lee, Changha
    • Journal of Soil and Groundwater Environment
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    • v.18 no.4
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    • pp.50-57
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    • 2013
  • For the last couple of decades, the Fenton (-like) systems have been extensively studied for oxidation of organic contaminants in water. Recently, zero-valent iron (ZVI) has received attention as a Fenton catalyst as well as a reducing agent capable of producing reactive oxidants from oxygen. In this study, the ZVI-based Fenton reaction was assessed for the oxidative degradation of phenol using $ZVI/O_2$, $ZVI/H_2O_2$, ZVI/Oxalate/$O_2$ and hv/ZVI/Oxalate/$O_2$ systems. Reaction parameters such as pH and reagent dose (e.g., ZVI, $H_2O_2$, and oxalate) were examined. In the presence of oxalate (ZVI/Oxalate/$O_2$ and hv/ZVI/Oxalate/$O_2$ systems), the degradation of phenol was greatly enhanced at neutral pH values. It was found that ZVI accelerates the Fenton reaction by reducing Fe(III) into Fe(II). The conversion of Fe(III) into Fe(II) by ZVI was more stimulated at acidic pH than at near-neutral pH values.

Reduction of PCBs in Contaminated Marine Sediments by Using Fenton-like Reaction with Surfactants (유사-펜톤 반응과 계면활성제에 의한 해양퇴적물의 PCBs 정화)

  • Choi, Jin Young;Kim, Kyoungrean
    • Journal of Korean Society of Environmental Engineers
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    • v.37 no.6
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    • pp.340-348
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    • 2015
  • Removal efficiency of PCBs in contaminated marine sediments treated by Fenton-like oxidation combined with surfactant was investigated in this research in order to achieve remediation of PCBs. A washing treatment using various concentrations of hydrogen peroxide (1% and 15%) and surfactants (Triton X-100, Tween 60 and Tween 80) was evaluated at various conditions in laboratory scale experiments. The mean removal efficiencies of tPCBs varied from 24.1 to 46.7% in the sediments for 1 hour duration of the treatments. The concentration of tPCBs in contaminated marine sediments after the simultaneous treatment with hydrogen peroxide and surfactant satisfied the domestic environmental standards for the beneficial use of sediments. When suitable surfactant was used for Fenton-like oxidation, the removal efficiency of tPCBs at low concentration of hydrogen peroxide was similar to that at high hydrogen peroxide concentration. Thus the efficient removal of PCBs in contaminated marine sediments could be achieved through treatment with Fenton-like oxidation combined with surfactant washing.

Manganese Oxide Catalyzed Fenton-like Reduction of Chlorinated Compounds (산화망간으로 촉매화된 펜톤유사반응을 적용한 염소계화합물의 환원분해)

  • 김상민;공성호;김용수
    • Journal of Soil and Groundwater Environment
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    • v.7 no.3
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    • pp.95-102
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    • 2002
  • Manganese oxide/ hydrogen peroxide($MnO_2$/${H_2}{O_2}$) reactions were investigated as an alternative to Fenton-like reaction to reduce chlorinated organic compounds in groundwater This system showed high degradation of CT with low ${H_2}{O_2}$concentration($\leq$294mM) at neutral condition, and CT degradation increased with increasing pH values. The rate of CT degradation was not so much dependent on increase in $MnO_2$concentration since increase in production of oxygen during the reaction obstructed reaction of ${H_2}{O_2}$ on the surface of $MnO_2$. These results show that $MnO_2$catalyzed Ponton-like reaction could be a potential alternative method for treating chlorinated organic compounds in groundwater.

Electrokinetic-Fenton Process for Removal of Phenanthrene (동전기-펜턴 공정을 이용한 phenanthrene 오염토양의 정화)

  • 양지원;박지연;김상준;이유진;기대정
    • Journal of Soil and Groundwater Environment
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    • v.9 no.1
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    • pp.47-53
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    • 2004
  • Feasibility of electrokinetic process combined with Fenton-like reaction was investigated for the removal of phenanthrene from contaminated soil. Transport of hydrogen peroxide by electroosmosis and decomposition of phenanthrene by Fenton-like reaction were observed in a model system. Electrical potential gradient and electroosmotic flow (EOF) at 10 mA were higher than those at 5 mA. High accumulated EOF resulted in high removal efficiency of phenanthrene because the large amount of hydrogen peroxide was transfered through the soil. Removal efficiency of phenanthrene by water washing was 8.5% for 7 days. The highest removal efficiency including phenanthrene decomposition was 95.6% for 14 days. After the operation, soil samples with removal efficiency of 95.6% showed low concentrations of phenanthrene and its intermediates. From this result, it was presumed that phenanthrene was decomposed to small molecules or mineralized to water and carbon dioxide due to continuous supply of hydrogen peroxide by electroosmotic flow.

Rational design of rare-earth orthoferrite LnFeO3 via Ln variation towards high photo-Fenton degradation of organics

  • Thi T. N. Phan;Aleksandar N. Nikoloski;Parisa A. Bahri;Dan Li
    • Advances in nano research
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    • v.16 no.1
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    • pp.41-52
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    • 2024
  • In this study, rare-earth orthoferrites LnFeO3 were synthesized using a facile hydrothermal reaction and their visible-light-induced photo-Fenton degradation of organics was optimized through Ln variation (Ln = La, Pr, or Gd). The morphological, structural, and chemical characteristics of as-prepared samples were examined in detail by using different methods, including XRD, SEM, TEM, XPS, etc. On the other side, under visible light illumination, the photo-Fenton-like catalytic activities of LnFeO3 were assessed in terms of the removal of selected organic models, i.e., pharmaceuticals (ketoprofen and tetracycline) and dyes (rhodamine B and methyl orange). As compared with PrFeO3 or GdFeO3, the sample of LaFeO3 displayed more structural distortion, larger specific surface area, and narrower band gap, resulting in its higher photo-Fenton-like catalytic activity toward the degradation of organics. In organic-containing solution, in which the initial solution pH = 5, catalyst dosage = 1 g/L and H2O2 concentration = 10 mM, 98.2% of rhodamine B, 31.1% of methyl orange, 67.7% of ketoprofen, or 96.4% of tetracycline was removed after 90-min exposure to simulated visible light. Our findings revealed that variation of Ln site on rare-earth orthoferrites was an effective strategy for optimizing their organic removal via visible-light-induced photo-Fenton reaction.

Phenanthrene으로 오염된 Kaolinite에 Electrokinetic-Fenton 기법 적용시 묽은 산의 주입에 따른 효과

  • 김정환;김기년;한상재;김수삼
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.04a
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    • pp.318-321
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    • 2003
  • This study explored the feasibility of applying Electrokinetic-Fenton process(EK-Fenton process) to remediation of contaminant sorbed on the soil possessed low-permeability. The addition of 0.01 N H$_2$SO$_4$ in the anode reservoir for the $H_2O$$_2$stabilization improved the stabilization of $H_2O$$_2$and the treatment effect of phenanthrene across the entire soil specimen. The use of $H_2O$$_2$and dilute acid as anode purging solution is a promising method treating of HOCs in low-permeability subsurface environments.

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Oxidative damage of DNA induced by the reaction of methylglyoxal with lysine in the presence of ferritin

  • An, Sung Ho;Kang, Jung Hoon
    • BMB Reports
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    • v.46 no.4
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    • pp.225-229
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    • 2013
  • Methylglyoxal (MG) is an endogenous metabolite which is present in increased concentrations in diabetics and reacts with amino acids to form advanced glycation end products. In this study, we investigated whether ferritin enhances DNA cleavage by the reaction of MG with lysine. When plasmid DNA was incubated with MG and lysine in the presence of ferritin, DNA strand breakage was increased in a dose-dependent manner. The ferritin/MG/lysine system-mediated DNA cleavage was significantly inhibited by reactive oxygen species (ROS) scavengers. These results indicated that ROS might participate in the ferritin/MG/lysine system-mediated DNA cleavage. Incubation of ferritin with MG and lysine resulted in a time-dependent release of iron ions from the protein molecules. Our data suggest that DNA cleavage caused by the ferritin/MG/lysine system via the generation of ROS by the Fenton-like reaction of free iron ions released from oxidatively damaged ferritin.

Degradation of Phenol with Fenton-like Treatment by Using Heterogeneous Catalyst (Modified Iron Oxide) and Hydrogen Peroxide

  • Lee, Si-hoon;Oh, Joo-yub;Park, Yoon-chang
    • Bulletin of the Korean Chemical Society
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    • v.27 no.4
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    • pp.489-494
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    • 2006
  • Goethite, hematite, magnetite and synthesized iron oxide are used as catalysts for Fenton-type oxidation of phenol. The synthesized iron oxides were characterized by X-ray diffraction (XRD), BET, X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR). The catalytic activity of these materials is classified according to the observed rate of phenol oxidation. The effectiveness of the catalysts followed the sequence: ferrous ion > synthesized iron oxide >> magnetite hematite > goethite. According to these results, the most effective iron oxide catalyst had the structure similar to natural hematite. The surface oxidation state of the catalyst was between magnetite and hematite (+2.5 ~ +3.0). Phenol degraded completely in 40 min at neutral pH (pH = 7). Soluble ferric and ferrous ions were not detected in the filtrate from Fenton reaction solution by AAS. The formation of hydroxyl radicals was confirmed by EPR.

Oxidative Damage of DNA Induced by the Cytochrome c and Hydrogen Peroxide System

  • Kim, Nam-Hoon;Kang, Jung-Hoon
    • BMB Reports
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    • v.39 no.4
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    • pp.452-456
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    • 2006
  • To elaborate the peroxidase activity of cytochrome c in the generation of free radicals from $H_2O_2$, the mechanism of DNA cleavage mediated by the cytochrome c/$H_2O_2$ system was investigated. When plasmid DNA was incubated with cytochrome c and $H_2O_2$, the cleavage of DNA was proportional to the cytochrome c and $H_2O_2$ concentrations. Radical scavengers, such as azide, mannitol, and ethanol, significantly inhibited the cytochrome c/$H_2O_2$ system-mediated DNA cleavage. These results indicated that free radicals might participate in the DNA cleavage by the cytochrome c and $H_2O_2$ system. Incubation of cytochrome c with $H_2O_2$ resulted in a time-dependent release of iron ions from the cytochrome c molecule. During the incubation of deoxyribose with cytochrome c and $H_2O_2$, the damage to deoxyribose increased in a time-dependent manner, suggesting that the released iron ions may participate in a Fenton-like reaction to produce $\cdot$OH radicals that may cause the DNA cleavage. Evidence that the iron-specific chelator, desferoxamine (DFX), prevented the DNA cleavage induced by the cytochrome c/$H_2O_2$ system supports this mechanism. Thus we suggest that DNA cleavage is mediated via the generation of $\cdot$OH by a combination of the peroxidase reaction of cytochrome c and the Fenton-like reaction of free iron ions released from oxidatively damaged cytochrome c in the cytochrome c/$H_2O_2$ system.

Fenton-like Reaction for Treatment of Petroleum-Contaminated Silty Clay after Soil Washing Process (토양세척 후의 유류 오염 Silty Clay 처리를 위한 유사펜톤 산화반응)

  • So, Myung-Ho;Ha, Ji-Yeon;Yu, Jae-Bong;Kim, Chang-Gyun
    • Journal of Korean Society of Environmental Engineers
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    • v.31 no.1
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    • pp.1-8
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    • 2009
  • This research was performed to assess a Fenton-like oxidation using naturally present iron in the field to treat remained oils throughout silty clay residues which finally resided even after a series of soil washing process. Biodegradability was thus tested for reaction products to investigate a possible treatment of the Fenton-like oxidation coupled with a biological treatment process. For those purposes, two types of field soil samples (e.g., dewatered cake after conditioning with a polymer and not-dewatered residue) were tested to remove TPH by adding the various concentration of hydrogen peroxide ($H_2O_2$). Moreover the biodegradability of treated samples was observed based on the ratio of $BOD_5/COD_{Cr}$ after Fenton-like oxidation. The Highest removal of TPH was at 1% of hydrogen peroxide ($H_2O_2$) when hydrogen peroxide ($H_2O_2$) was continuously injected for a period of time rather than that of spot introduction with the same amount of it. For the dewatered cake, TPH was effectively treated when the ratio of solid and water was mixed at 1 : 2. Employing cooking oil could increase solubility of TPH due to enhanced surface-active escalating TPH desorption from silty clay. Nonetheless, the biodegradability was decreased as long as the oxidation duration being extended regardless of operational conditions. It was therefore proved that Fenton-like oxidation using $H_2O_2$ and natural iron minerals was able to remove adsorbed oils in silty clay but the removal efficiency of TPH was low. And if a biological treatment process followed after Fenton-like oxidation, microorganisms would need enough time for acclimation.