JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART A-TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING
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2011
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IF 1.107
Zhiqiao He,Angliang Zhang,Yu Li,Shuang Song,Zhiwu Liu,Jianmeng Chen,Xinhua Xu
Ozonation combined with UV irradiation (UV/O3) is an advanced oxidation technique that is very promising for the destruction of organic compounds in aqueous solution. In this study, chlorophene was chosen as a model substrate to investigate the effects of pH, initial substrate concentration, ozone dose, and UV light intensity in degradation experiments. The pseudo–first-order rate constant for total organic carbon (TOC) removal was 2.4 × 10−2, 9.8 × 10−4, and 6.4 × 10−2 min−1 for O3, UV, and UV/O3 treatment, respectively. Clearly, UV-enhanced ozonation leads to a synergetic increase in the overall degradation efficiency. Comparative experiments were performed to investigate the effect of the matrix (distilled water or sewage) on chlorophene removal. The organic compounds in sewage retarded the rate of chlorophene removal by 38%, probably by competitively reacting with the oxidizing agent and screening light. The compound 2-benzoylbenzo-1,4-quinone, benzo-1,4-quinone, hydroquinone and maleic acid were identified as primary intermediates by gas chromatography-mass spectrometry. The concentrations of acetic, formic and oxalic anions were detected by ion chromatography. A possible degradation pathway is proposed on the basis of the reaction products identified.
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
Scientific Reports
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2016
·Vol. 6
·期 1
·1-11
·
IF 5.228
Xiang Wei,Zhang Beiping,Zhou Tao,Wu Xiaohui,Mao Juan
This study demonstrated the synergistic degradation of 4-chlorophenol (4-CP) achieved in a magnetic field (MF) enhanced zero-valent iron (ZVI)/H 2 O 2 Fenton-like (FL) system and revealed an interesting correlative dependence relationship between MF and the pristine iron oxides layer (Fe x O y ) on ZVI particles. First, a comparative investigation between the FL and MF-FL systems was conducted under different experimental conditions. The MF-FL system could suppress the duration of initial lag degradation phase one order of magnitude in addition of the significant enhancement in overall 4-CP degradation. Monitoring of intermediates/products indicated that MF would just accelerate the Fenton reactions to produce hydroxyl radical more rapidly. Evolutions of simultaneously released dissolved iron species suggested that MF would not only improve mass-transfer of the initial heterogeneous reactions, but also modify the pristine ZVI surface. Characterizations of the specific prepared ZVI samples evidenced that MF would induce a special evolution mechanism of the ZVI particles surface depending on the existence of Fe x O y layer. It comprised of an initial rapid point dissolution of Fe x O y and a following pitting corrosion of the exposed Fe 0 reactive sites, finally leading to appearance of a particular rugged surface topography with numerous adjacent Fe 0 pits and Fe x O y tubercles.
研究领域:
环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
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2025
·Vol. 39
·期 5
·e70103
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IF 0
Palanisamy Vasudhevan,Dong Yu,Ruoyu Zhang,Mysoon M. Al-Ansari,Velu Manikandan,Hui Ma,Saurav Dixit,Shengyan Pu
Chlorinated aromatic chemicals are highly hazardous, transmissible, and bioaccumulative. Developing an economically feasible catalytic method to facilitate the effective removal of chlorinated aromatic pollutants is critical for contamination prevention. The current study extensively investigated the utilization of organic ligands such as citrate (CA) and ethylenediaminetetraacetic acid (EDTA) to increase Fe(II)-activated persulfate (PS) for 4-chlorophenol (4-CP) and 3-chlorobenzoic acid (3-CB) degradation in water. The decomposition and consumption ability of persulfate in PS alone and Fe(II)/PS systems for 4-CP and 3-CB was very low because of the rapid utilization as well as discontinuous availability of Fe(II), which indicates the decline of Fe(III) to Fe(II). But, when using the citrate/Fe(II)/PS and EDTA/Fe(II)/PS combinations, the degradation of 4-CP and 3-CB was 78.86%, 75.01% and 84.84%, 80.99% within 30 min, respectively. The significant enhancement is due to both ligand-to-metal transfer of charges process, and this increased the process of rate determination through carrying electrons into the citrate and EDTA ligands to Fe(III), generating Fe(II). In addition, the 4-CP and 3-CB degradation facilitated with citrate/Fe(II)/PS and EDTA/Fe(II)/PS systems was efficiently degraded at acidic pH (2.0–6.0) conditions. The pseudo-first-order kinetics model accurately predicted 4-CP and 3-CB degradation in the organic ligand/Fe(II)/PS systems. The degradation percentage of 4-CP and 3-CB increased with increasing PS and Fe(II) concentrations. Moreover, both sulfate and hydroxyl radicals formed by citrate/Fe(II)/PS and EDTA/Fe(II)/PS systems were identified as major reactive oxygen species for 4-CP and 3-CB decomposition. The present investigation recommends an alternate strategy to enhance the Fe(II)-activated persulfate mechanisms.
研究领域:
环境科学
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化学
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产品关联
DOI
APPLIED CATALYSIS B-ENVIRONMENTAL
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2016
·
IF 8.328
Xia Chen,Wangyang Lu,Tiefeng Xu,Nan Li,Dandan Qin,Zhexin Zhu,Gangqiang Wang,Wenxing Chen
In nature, metalloporphyrins, such as chlorophyll, cytochrome P450 and so forth, are key materials in maintaining the ecological cycles, especially the carbon cycle, and play an important role in both photosynthesis and the catalytic oxidation of organisms. Inspired by these factors, we skillfully combined photocatalysis and biomimetic catalysis using imidazole (IMD)-functionalized modification of g-C 3 N 4 and axial coordination with hemin. Compared with pure hemin, g-C 3 N 4 and a mixture of the two, our novel catalytic system (g-C 3 N 4 -IMD-hemin/H 2 O 2 ) showed high photocatalytic oxidation activity for the degradation of 4-chlorophenol (4-CP), and the stability of hemin was enhanced under solar irradiation. Furthermore, the effect of pH and the sustained photocatalytic oxidation stability of g-C 3 N 4 -IMD-hemin for degrading 4-CP were investigated. The results indicated that g-C 3 N 4 -IMD-hemin presents a high photocatalytic oxidation activity over a wide pH range and exhibits good recyclability. A series of designed experiments showed that superoxide radicals ( O 2 − ), high-valent iron (Fe(IV) = O) species, peroxy radicals ( OOH) and few hydroxyl radicals ( OH) were generated in the g-C 3 N 4 -IMD-hemin/H 2 O 2 system. This synergistic photocatalytic and biomimetic process offers new insight for the utilization of solar energy and offers a new perspective for the exploration of catalysts for environmental remediation.
研究领域:
环境科学
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生物化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2014
·
IF 6.007
Qi Huang,Menghua Cao,Zhihui Ai,Lizhi Zhang
In this study, an environmentally benign polyaminocarboxylic ligand diethylenetriamine pentacetate (DTPA) was first used to promote the aerobic 4-chlorophenol (4-CP) degradation with Fe@Fe 2 O 3 core–shell nanowires, and then compared with the most used counterpart ethylenediamine tetraacetate (EDTA) of poor biodegradability. Although the 4-CP removal rate in the Fe@Fe 2 O 3 /DTPA/Air system was slower owing to the preferential degradation of DTPA, the total organic carbon removal rate in the Fe@Fe 2 O 3 /DTPA/4-CP/Air system was much faster than that in the Fe@Fe 2 O 3 /EDTA/4-CP/Air system. We interestingly found that hydroxyl radicals could more easily react with DTPA to produce DTPA radicals than with EDTA to produce EDTA radicals. Ligands (DTPA or EDTA) could significantly accelerate the hydroxyl radicals production with Fe@Fe 2 O 3 , while more hydroxyl radicals were generated in the Fe@Fe 2 O 3 /DTPA/Air system. We also employed gas chromatography-mass spectrometry and ion chromatography to detect organic intermediates and chloride ions to probe the 4-chlorophenol degradation pathways, and found its degradation pathways were dependent on the reactive oxygen species generated in the different systems. This study can clarify the roles of polyaminocarboxylic ligands on the molecular oxygen activation with nanoscale zero-valent iron, and also provide a green chlorophenols removal method.
研究领域:
环境科学
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化学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2024
·
IF 7.7
Palanisamy Vasudhevan,Dharman Kalaimurugan,Sivarasan Ganesan,Naveed Akbar,Saurav Dixit,Shengyan Pu
Agricultural residues are one of the most cost-effective and readily accessible carbon resources for producing commercially significant enzymes. Several enzymes have been used in different industries like pharmaceuticals, foods, textiles, and dyes that can be generated by various species of microbes found in waste from agriculture. The current research investigated laccase production by Aspergillus oryzae utilizing agricultural wastes. Physical and chemical properties, including pH, temperature, sucrose, yeast extract, and copper sulfate levels, were optimized. The utilization of the response surface methodology along with the centralized composite design method, which assesses multiple media parameters and utilizes a two-level experimental approach, aids in determining the variable and its significance in increasing production quality. The centralized composite design enhancement showed that the optimal conditions for highest laccase activity (623.16 U/mL) were pH 7.0, temperature 25 °C, corn cobs as substrate, sucrose (2.0 %), yeast extract (1.0 %), and copper sulfate (0.1 mM) level. The laccase enzyme was optimized using various pH, temperature, metal ions, and inhibitors combinations. The extracted laccase enzyme maximum activity was attained at pH 6.0 and 40 °C. The inclusion of divalent ions can enhance laccase activity, while the use of various inhibitors decreases laccase activity. Under various pH circumstances, the Aspergillus oryzae laccase enzyme can successfully degrade p-chlorophenol. The present study describes statistically validated optimal methodologies for enhancing laccase synthesis, leading to a laccase production technique that is simultaneously highly efficient and economically profitable, with possible use of p-chlorophenol degradation.
研究领域:
环境科学
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生物技术
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产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2020
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IF 6.551
Quan Gan,Huijie Hou,Sha Liang,Jingjing Qiu,Shuangyi Tao,Liang Yang,Wenbo Yu,Keke Xiao,Bingchuan Liu,Jingping Hu,Yanfei Wang,Jiakuan Yang
Fe-rich biochar with multivalent iron compounds (Fe 0 , Fe 0.95 C 0.05 , Fe 3 O 4 , and FeAl 2 O 4 ) pyrolyzed from sludge cake conditioned with Fenton's reagent and red mud was utilized as an efficient Fenton catalyst for the degradation of 4-chlorophenol (4-CP). Effects of pyrolysis temperature and sludge conditioner composition on the transformation of iron compounds were studied. Both homogeneous Fenton reaction initiated by Fe 2+ leached from both low-valent Fe 0 and Fe 0.95 C 0.05 , and heterogeneous Fenton reaction initiated by solid iron phases of Fe 3 O 4 and FeAl 2 O 4 were revealed to contribute to the degradation of 4-CP. The removal efficiency of 4-CP remained 100% after five successive degradation rounds. The homogeneous Fenton reaction mainly works in the first degradation round, and the heterogeneous Fenton reaction dominates in subsequent degradation rounds. The findings of this study suggest that sewage sludge derived Fe-rich biochar could be utilized as an efficient Fenton catalyst for recalcitrant organics degradation .
研究领域:
环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2016
·
IF 5.31
Xiang Li,Minghua Zhou,Yuwei Pan,Liting Xu
The abatement of chlorophenols is of great environmental importance. Though Fe 0 can activate persulfate (PS) to improve performance, our findings proved that pre-magnetized Fe 0 (Pre-Fe 0 ) could significantly enhanced the degradation and dechlorination of 2,4-dichlorophenol (2,4-DCP), and this Pre-Fe 0 /PS process was more efficient than Fe(II)/PS. The Fe 0 before and after magnetization was characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), suggesting the acceleration of Fe 2+ release after magnetization. The effects of some important operating parameters such as Fe 0 dosage, PS dosage, pH, and initial 2,4-DCP concentration on the 2,4-DCP degradation and dechlorination by Pre-Fe 0 /PS were investigated and compared with that of Fe 0 /PS, observing a 1.9–5.2-fold enhancement in the degradation rate of 2,4-DCP. Although SO 4 − was the dominant active species responsible for 2,4-DCP degradation in two processes, pre-magnetization could promote more OH generation. Identified by GC–MS and IC, the degradation intermediates such as 4-chlorophenol (4-CP), 2-chlorophenol (2-CP), phenol, and some carboxylic acids were detected, and possible degradation pathway was proposed. This Pre-Fe 0 /PS process was also efficient for 4-chlorophenol and chlorobenzene degradation, obtaining a 5.2 and 3.2 folds enhancement, respectively. This work demonstrated that such a Pre-Fe 0 /PS would be very promising and environmental-friendly for organics degradation and dechlorination since pre-magnetization required no extra energy source while the introduction of Pre-Fe 0 was rather simple and no need to change the present treatment system.
研究领域:
环境科学
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化学
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产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 29
·期 48
·72764-72776
·
IF 5.19
Zhong Dan,Feng Weinan,Ma Wencheng,Liu Xinyue,Ma Jun,Zhou Ziyi,Du Xuan,He Fu
Goethite and lepidocrocite, as the main compositions of pipe deposits in the water distribution network, could be used as a catalyst for advanced oxidation processes (AOPs). This research utilizes them to activate PDS/H 2 O 2 and PMS/H 2 O 2 degrading the 2,4,6-trichlorophenol, respectively. To describe the incomplete degradation of pollutants and reflect the induction period, a modified first-order model has been proposed and used to analyze degradation differences under several key affecting factors. The results revealed that the PDS/H 2 O 2 system has a synergy effect in the 2,4,6-trichlorophenol degradation process. The possible degradation pathways and intermediate products were confirmed by gas chromatograph-mass spectrometry (GC–MS). The paper provides a new idea for the effective use of pipe deposits to remove chlorophenols from drinking water, which is of great significance to ensure water quality safety.
研究领域:
环境科学
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水处理技术
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产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2017
·
IF 9.446
Shengjie Xia,Xiaofeng Zhang,Xiaobo Zhou,Yue Meng,Jilong Xue,Zheming Ni
In this paper, we synthesized a series of novel layered double hydroxides (LDHs) based materials with different organic/inorganic Cu species (Cu 3 O/CuCr 1 –Cu 2 /SB–LDHs). The Cu species were distributed in the layers (defined as Cu 1 ), intercalated between the layers (Cu 2 ) and combined on the surface of the material (Cu 3 ), respectively. The percentage of each Cu specie was adjusted to reveal the connection between different modifications and their photocatalytic activities as well as the modifications and the mechanism towards the chlorophenol (2,4,6-TCP) degradation. The experimental results showed that photodegradation of TCP varied due to different Cu species, the catalyst with the highest Cu concentration between the layers had the highest TCP degradation rate of 95.1%. In addition, the apparent quantum efficiency of different Cu 3 O/Cu 1 Cr–Cu 2 /SB–LDH materials was at the range of 0.42% to 0.60%, which was higher than that of CuCr–LDHs (0.21%) and CuCr–CuSB–LDHs (0.32%). The free radical tests showed that different Cu species determined the generation of hydroxyl radical, super oxide free radical and peroxy radicals, differently. These three radicals contributed to 46.2%, 22.5% and 10.9%, respectively, for TCP degradation during the photocatalytic reaction. Therefore, it is critical to study the influence of different Cu modifications to the improvement of photocatalytic reactivity and selectivity of Cu 3 O/Cu 1 Cr–Cu 2 /SB–LDH material. In addition, the intermediates, pathway and photoreaction mechanism of TCP degradation were also investigated in detail.
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
Frontiers in Chemistry
·
2022
·
IF 5.545
Wang Yangyang,Xu Jianfeng,Wang Xiaoshu,Li Tongtong,Zhang Gen,Yan Zheng,Liu Jiancong,Wang Lei
The background value of iron in red soil is superior, primarily absorbed and homogeneously encapsulated in harvested biomass. However, this property on the high-value utilization of bionic iron-encapsulated biomass remains unknown. In this study, special biochar (Fe@BC) was obtained from this kind of biomass by one-step pyrolysis method, which was further used to activate peroxydisulfate (PDS) and degrade 2,4-dichlorophenol (2,4-DCP). The results showed that Fe3O4 was formed and homogeneously embedded in biochar at 500oC. Comparing to catalysts prepared by impregnation pyrolysis (Fe/BC), Fe@BC exhibited excellent degradation performance (90.9%, k = 0.0037 min−1) for 2,4-DCP. According to the free radicals quenching studies, hydroxyl radicals (·OH) and superoxide radicals (·O2−) were the dominant reactive oxygen species (ROS) in Fe@BC/PDS system. Importantly, a PDS adsorption model was established, and the electron transport and PDS activation in the core-shell structure were demonstrated by DFT calculations. Therefore, this study could supply a high-performance catalyst and significant implications for high-value biomass utilization in red soil.
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 HAZARDOUS MATERIALS
·
2021
·
IF 10.588
Bin Zhang,Jun Ma,Huizhong Chi,An Ding,Yanjun Xin,Yingying Ma,Qingliang Liu,Xu He
Given the limitations of conventional vacuum ultraviolet (VUV) systems, a novel vacuum ultraviolet/graphite carbon nitride (VUV/g-C 3 N 4 ) system with high adaptability to varying environmental conditions was developed. Compared with conventional VUV and UV/g-C 3 N 4 systems, the VUV/g-C 3 N 4 system demonstrates a much higher ability for the efficient degradation of chlorophenols (CPs). In particular, the VUV/g-C 3 N 4 system exhibits outstanding performance even at low pH and high concentrations of humic acid and SO 4 2- . Alkaline conditions and the presence of HCO 3 - can further promote CP removal. In addition, the feasibility of the VUV/g-C 3 N 4 system was verified by its stable operation in both river water and tap water . Unlike conventional photochemical systems relying on •OH, the dominant reactive species for CP degradation by the VUV/g-C 3 N 4 system was identified to be •O 2 - . This study conclusively provided a novel system for the efficient photocatalytic treatment of pollutants.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子