ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2025
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IF 11.3
Dashi Lei,Yiyao Zhang,Xiaofei Sun,Liqin Li,Qingchao Zhao,Xiangyu Peng,Juanqin Xue,Yubin Wang,Jing Zhang
Reduced chromite ore processing residue (rCOPR) is vulnerable to the surrounding conditions in environments, which can induce the release and oxidation of Cr(III). This work found the synergistic effect of light and sulfite on destroying rCOPR stability, causing the significant release of Cr(VI), which was 4∼7 times higher than that under single factor action. In CrxFe1–x(OH)3/sulfite/light system, Cr(VI) release rate could reach 11.11 × 10–7 M min–1 g–1, because of the rapid formation of ·OH, O2·–, SO4·–, and quadrivalent iron [Fe(IV)]. In addition, this study found that the oxidized chromium residue could continuously release Cr(III) after being transferred to the dark environment. This should be attributed to the obvious change in the iron coordination structure of rCOPR caused by the catalytic reaction of sulfite with light, which greatly weakened the ability of the Fe–O structure to encase chromium elements in a solid. These insights are crucial for predicting the environmental risks of rCOPR in the presence of visible light and sulfur-containing compounds.
研究领域:
环境科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2016
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IF 5.31
Shiqing Zhou,Lingjun Bu,Zhou Shi,Chen Bi,Qihang Yi
In this work, iron electrode was employed to enhance the reactivity of ozone (EC/O 3 ) in atrazine degradation. Compared to ozonation and Fe 2+ -catalyzed ozonation, the elimination rate of atrazine by the EC/O 3 process increased significantly with increasing applied currents. The simultaneous formation of hydroxyl radical (OH ) and ferryl ion (Fe(IV)) from the reaction between ozone and in-situ formed Fe 2+ was proposed and experimentally confirmed. The second order rate constant for atrazine reacting with Fe(IV) was estimated to be 125 M −1 s −1 using a relative rate method. The individual roles of the reactive species (OH , Fe(IV), and O 3 ) in atrazine degradation were modeled using a kinetic model and OH was the predominant reactive species in the EC/O 3 system. Furthermore, the effects of water quality parameters, such as initial pH and natural organic matters (NOM), on the performance of EC/O 3 process were also evaluated. The results demonstrated that higher initial pH is favorable for ozone consumption and atrazine degradation. The presence of NOM appreciably inhibited the degradation of atrazine, which may be attributed to the competition of NOM for OH . This study provides a new approach to enhance ozonation, and broadens the knowledge of ozonation in removing organic contaminants from water.
研究领域:
环境科学
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水处理技术
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2021
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IF 9.028
Shuchang Wang,Yang Deng,Binbin Shao,Jiahui Zhu,Zixin Hu,Xiaohong Guan
For the first time, this study showed that the apparent second-order rate constants (kapp) of six selected emerging organic contaminants (EOCs) oxidation by Fe(VI) increased, remained constant, or declined with time, depending on [EOC]0/[Fe(VI)]0, pH, and EOCs species. Employing excess caffeine as the quenching reagent for Fe(V) and Fe(IV), it was found that Fe(V)/Fe(IV) contributed to 20–30% of phenol and bisphenol F degradation by Fe(VI), and the contributions of Fe(V)/Fe(IV) remained nearly constant with time under all the tested conditions. However, the contributions of Fe(V)/Fe(IV) accounted for over 50% during the oxidation of sulfamethoxazole, bisphenol S, and iohexol by Fe(VI), and the variation trends of kapp of their degradation by Fe(VI) with time displayed three different patterns, which coincided with those of the contributions of Fe(V)/Fe(IV) to their decomposition with time. Results of the quenching experiments were validated by simulating the oxidation kinetic data of methyl phenyl sulfoxide by Fe(VI), which revealed that the variation trends of kapp with time were significantly determined by the change in the molar ratio of Fe(V) to Fe(VI) with time, highlighting the key role of Fe(V) in the oxidative process. This study provides comprehensive and insightful information on the roles of Fe(V)/Fe(IV) during EOC oxidation by Fe(VI).
研究领域:
环境科学
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化学动力学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
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IF 13.3
Wei Lin,An Ding,Chuangxin Gong,Xiuxiang Ding,Peter Desmond,Piotr Oleskowicz-Popiel,Xu He,Jun Ma,Huu Hao Ngo
Sludge reduction is essential for mitigating the environmental hazards associated with sludge. The use of ferric chloride (Fe(III)) catalyzed ferrate (Fe(VI)) can significantly enhance sludge dewaterability by increasing the Fe(VI) oxidation rate and maintaining in-situ enhanced coagulation. However, its weak oxidation ability at the sludge’s original pH limits its practical application. To address this, hydrogen peroxide (H 2 O 2 ) strengthened Fe(VI)/Fe(III) was employed to efficiently improve sludge dewaterability without pH adjustment, thereby enhancing the environmental utilization capacity of sludge. Compared to raw sludge, the treatment of Fe(VI)/Fe(III)–H 2 O 2 resulted in approximately the 95% reduction in specific resistance to filtration (SRF) and increased the bioavailable phosphorus (P) content in dewatered sludge. During the oxidation process, highly reactive species such as tetravalent iron (Fe(IV)) and hydroxyl radicals ( OH) were generated, facilitating the release of tightly bound water in extracellular polymeric substances (EPS). Importantly, the oxidation process was divided into three stages (persistent moderate oxidation — fast strong oxidation — sustained weak oxidation) based on the predominant reactive species (Fe(IV) or OH). This division promoted more robust and more durable oxidation processes. Phased enhanced coagulation occurred during the oxidation process. The gradual increase in Fe(III) content led to the re-flocculation of damaged EPS, enlarging the size of sludge drainage pores/channels and improving water discharge efficiency. Additionally, the costs and carbon emissions of chemicals for the Fe(VI)/Fe(III)–H 2 O 2 process were 18% and 52% lower than those of the traditional Fenton method. This study not only achieves the goals of sludge reduction and resource collection but also provides insights into selecting sludge conditioning methods that meet pollution reduction and carbon emission reduction requirements.
研究领域:
环境科学
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污水处理
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Mingyang Dai,Shaobo Liu,Xiaofei Tan,Qiang Chen,Jian Ye,Ang Sun,Ni Liu
The recycling and utilization of waste biomass resources have attracted widespread attention due to their enormous potential economic value. In this study, a magnetic zero-valent iron nanoflake-modified graphitic mesoporous carbon composite (Fe@SBCx) was prepared using ultrasound-assisted impregnation and pyrolysis strategies, and employed as an efficient peroxydisulfate (PDS) activator for the removal of the antibiotic norfloxacin (NOR) from water. The Fe@SBC 1.13 /PDS system exhibited excellent oxidation performance, achieving nearly complete removal (>99 %) of 10 mg/L NOR within 25 min. Singlet oxygen ( 1 O 2 ) and ferryl iron species (Fe(IV)) were identified as the major oxidative reactive species in the system. The formation of electron donor–acceptor complexes during the reaction facilitated the decomposition of PDS and the generation of oxidative species. Fe@SBC 1.13 demonstrated satisfactory recyclability and catalytic stability. Based on density functional theory (DFT) calculations and intermediate product analysis, the degradation pathways of NOR were proposed. Moreover, the toxicity evaluation results revealed a lower bacterial cytotoxicity in the treated drainage. Overall, this study not only enriches the theoretical research on the degradation mechanisms of fluoroquinolone antibiotics in the environment but also provides a viable approach for developing highly efficient and carbon–neutral catalysts.
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
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2025
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IF 6.7
Danni Deng,Rong Chen,Qianqian Zhong,Binbin Xiong,Jia Deng,Na Zhang,Shiwei Xie
Bicarbonate ions (HCO 3 − ), commonly present in natural water sources, exert complex influences on peroxymonosulfate (PMS)-based advanced oxidation processes (AOPs). This study investigates the role of HCO 3 − in a novel electrochemical system using a stainless-steel scrubber cathode (SSSC) for PMS activation. The buffering effect of HCO 3 − shifts the dominant Fe(II) species from dissolved Fe 2+ ions to surface-bound Fe(II) (≡Fe(II)) within the HCO 3 − /PMS/SSSC system. Furthermore, HCO 3 − promotes ≡Fe(II)/≡Fe(III) redox cycling on the SSSC surface. These synergistic effects significantly enhance PMS activation, generating singlet oxygen ( 1 O 2 ) and Fe IV O as the primary oxidants responsible for BPA degradation. Identification of degradation intermediates elucidated two dominant pathways: hydroxylation and radical coupling. Toxicity assessment of these intermediates confirmed reduced environmental risks. The SSSC exhibited long-term stability and effective performance in real water matrices, demonstrating its practical applicability.
研究领域:
环境科学
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电化学
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水处理
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高级氧化技术
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）