ADSORPTION SCIENCE & TECHNOLOGY
·
2013
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IF 0.559
Ping Yu,Qilong Sun,Jianming Pan,Zhenjiang Tan,Jiangdong Dai,Yongsheng Yan,Feng Cheng
Poly(styrene–divinylbenzene)/Fe3O4 (Fe3O4@St–DVB) magnetic porous polymer microspheres based on suspension polymerization were prepared for adsorption of 2, 4-dichlorophenol (2, 4-DCP) and 2, 6-dichlorophenol (2, 6-DCP) from aqueous solution. The as-prepared product was characterized by Fourier transform infrared spectroscopy, Raman, X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, differential thermal analysis and elemental analysis. The results showed that the composite material has both porous and magnetic characteristics, which aid in faster separation and increase in adsorption capacity. The adsorption performance of the Fe3O4@(St–DVB) magnetic porous microspheres was manifested by batch mode adsorption experiments with respect to pH, initial concentration, contact time and temperature. The adsorbent was found to be sensitive to changes in pH, and the adsorption capacity of 2, 4-DCP is higher than that of 2, 6-DCP. The kinetics experimental data fitted well with the pseudo-second-order model, as three steps belonged to the pseudo-second-order adsorption process. The adsorption isotherms were also described by the Langmuir and Freundlich isotherm models, respectively. It was found that the Langmuir isotherm model fitted the equilibrium data superior to the Freundlich model. Thermodynamic parameters were calculated by the Gibbs free energy function, confirming that adsorption process was spontaneous and endothermic. In addition, the reusability performance of the Fe3O4@(St–DVB) magnetic porous microspheres was demonstrated by four repeated cycles.
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
DOI
高影响因子
Progress in Natural Science-Materials International
·
2024
·
IF 4.8
Mengxia Ma,Zhaoyang Li,Xu Yan,Yanli Mao,Chaohai Wang,Haiyan Kang,Qun Yan,Jieqiang Zhou,Zhongxian Song,Dandan Pang
Magnetic flower-like α-Fe 2 O 3 @N–C particles were synthesized by hydrothermal self-assembly method and oxygen-limited carbonisation in a glycerol and ethanol solution system using glucose as the carbon source, iron nitrate as the magnetic source and particle skeleton and urea as the nitrogen source. Four hydrothermal temperatures of 120 °C, 140 °C, 160 °C and 180 °C were used to modulate the adsorbent structure. Hydrothermal temperature of 140 °C, solution pH = 7, and a dosage of 0.06 g are the optimum conditions. The adsorption capacity of 2,4-dichlorophenol (2,4-DCP) onto MC-2 was determined as 108.556 mg g −1 at 25 °C. Experiments show that the adsorbents all fitted well to the Langmuir isothermal adsorption model and the quasi-secondary kinetic model, and the adsorption behaviour was dominated by monolayer chemisorption . The adsorption process was heat absorbing and spontaneous. Raman and XRD analysis showed that the adsorbent had a stable α-Fe 2 O 3 skeleton and carbon layers. FTIR and XPS analysis showed that the adsorbent had hydrogen bonding , electrostatic interaction and π-π bonding to 2,4-dichlorophenol.
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
DALTON TRANSACTIONS
·
2024
·
IF 3.5
Xiaoyu Chu,Xinrui Wang,Shuo Tian,Yongkuo Zhao,Shikai Liu,Hong Yan,Yan Shang
Modulating the photogenerated electrons of CeO2 to activate O2 and efficiently photocatalytic degradation of chlorophenols is a highly desired goal. Herein, we have successfully fabricated FePc/CeO2 heterojunction through H-bond induced assembly. The photocatalytic degradation of 2, 4-DCP by the amount-optimized FePc/CeO2 nanocomposite was improved by 3 times compared with pure CeO2. By means of electron paramagnetic resonance (EPR) and single wavelength photocurrent spectroscopy, it is confirmed that the excellent photocatalytic performance is mainly attributed to the formation of Z-scheme heterojunction, which promotes charge separation and transfer, and the introduction of FePc broadens the visible light absorption range of heterojunction. Moreover, O2 temperature-programmed-desorbed curves and electrochemical O2 reduction measurements results demonstrate that the single Fe-N4(II) site in FePc is more conducive to promoting O2 activation than that of other metal phthalocyanines. Based on in situ FT-IR and liquid chromatography-tandem mass spectrometry (LC-MS), a possible reaction pathway of 2, 4-DCP degradation was proposed. This study provides a novel strategy to prepare CeO2 based Z-scheme heterojunctions with abundant monoatomic sites for pollutant degradation.
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
PubMed
高影响因子
WATER RESEARCH
·
2021
·
IF 11.236
Xiaoxue Pan,Junyan Wei,Mengting Zou,Jing Chen,Ruijuan Qu,Zunyao Wang
We systemically investigated the transformation behavior of 2,4-dichlorophenol (24-DCP) in seven different reaction systems including KMnO 4 , heat/PS, O 3 , UV, Fenton, NaClO and K 2 FeO 4 treatment. The results revealed that complete removal of 24-DCP could be reached in minutes, especially for Fe(VI), KMnO 4 , NaClO, Fenton and O 3 system. A total of 41 products were identified by LC-MS, and 10 of them were validated using commercial and self-synthesized standards. Hydroxyl substitution and coupling reactions were commonly observed in the studied systems. Meanwhile, extra routes such as sulfate substitution, (de)chlorination and direct oxidation were also involved for certain oxidation methods. Comparisons showed that a high degree of chlorination (>90%) occurred for NaClO system, while coupling products accounted for ~45% of the removed 24-DCP under PS oxidation. Moreover, low mineralization degree together with high aquatic toxicity was attributed to the occurrence of coupling reaction, which was possibly related to the redox potential of the main oxidative species. Considering the low abundance of coupling products and the gentle reaction condition, UV irradiation is a better option for 24-DCP removal in water and wastewaters. These findings can deepen our understanding on the transformation process of 24-DCP and provide some useful information for the environmental elimination of substituted phenols.
研究领域:
环境科学
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化学
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DOI
高影响因子
Journal of Environmental Sciences
·
2019
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IF 3.556
Kaiyuan Zheng,Yuqiao Song,Xu Wang,Xin Li,Xuhui Mao,Dihua Wang
Herein, with the exploitation of iron and nickel electrodes, the 2,4-dichlorophenol (2,4-DCP) dechlorinating processes at the anode and cathode, respectively, were separately studied via various electrochemical techniques (e.g., Tafel polarization, linear polarization , electrochemical impedance spectroscopy). With this in mind, Ni/Fe nanoparticles were prepared by chemical solution deposition, and utilized to test the dechlorination activities of 2,4-DCP over a bimetallic system. For the iron anode, the results showed that higher 2,4-DCP concentration and solution acidity aggravated the corrosion within the electrode. The charge transfer resistance ( R ct ) values of the iron electrode were 703, 473, 444, and 437 Ω ∙ cm 2 for the initial 2,4-DCP concentrations of 0, 20, 50, and 80 mg/L, respectively. When the bulk pH of the 2,4-DCP solution varied from 3.0, 5.0 to 7.0, the corresponding R ct values were 315, 376, and 444 Ω ∙ cm 2 , respectively. For the nickel cathode, the reduction current densities on the electrode at − 0.75 V (vs. saturated calomel electrode) were 80, 106, and 111 μA/cm 2 , for initial 2,4-DCP concentrations of 40, 80, and 125 mg/L. The dechlorination experiments demonstrated that when the initial pH of the solution was 7.0, 5.0, and 3.0, the dechlorination percentage of 2,4-DCP by Ni/Fe nanoparticles was 62%, 69%, and 74%, respectively, which was in line with the electrochemical experiments. 10 wt.% Ni loading into Ni/Fe bimetal was affordable and gave a good dechlorination efficiency of 2,4-DCP, and fortunately the Ni/Fe nanoparticles remained comparatively stable in the dechlorination processes at pH 3.0.
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
JOURNAL OF HAZARDOUS MATERIALS
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2020
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IF 9.038
Yichen Zhen,Qiang Zhang,Xiaoyan Zhang,Guanteng Zhang,Xiaoxin Chen,Chunxia Zhao
Chlorophenols (CPs) are still used as raw material or intermediate in some industries. Photocatalytic oxidation is free from secondary pollution, but the efficiency is restricted by some main factors. In this study, a novel high efficiency tubular up-flow magnetic film (TUMF) photocatalytic system was investigated based on the magnetic lanthanum doping core-shell Fe 3 O 4 @SiO 2 @TiO 2 (La-FST) nanoparticles. When the dosage of La-FST was 0.4 g/L, the flow velocity was 94.2 mL/min, and the circulated irradiation of 15 W maintained 40 min, the average removal rate of 2,4-dichlorophenol (2,4-DCP) was reduced significantly from 10 mg/L to 0.0803 mg/L by TUMF system, meeting the limits of the particular items (0.093 mg/L) from national environmental quality standards for surface water, avoiding the problem of photocatalyst separation and loss. The photoinduced holes ( h + ) was the key active radical to oxidize 2,4-DCP, and the main factors of TUMF system could be well controlled to achieve satisfactory effluent quality. A prediction method of photocatalytic reaction time in a multistage series TUMF system was established to remove 2,4-DCP from 100 mg/L to 0.5 mg/L, saving 86 min. The novel high-efficiency TUMF system provides a technical selection for the photocatalytic degradation of CPs and other refractory organics.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2015
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IF 4.529
Yunfang Chen,Jianzhang Fang,Shaoyou Lu,Yan Wu,Dazhi Chen,Liyan Huang,Cong Cheng,Lu Ren,Ximiao Zhu,Zhanqiang Fang
This study aims at photocatalytic degradation of 2,4-DCP with the assistance of H 2 O 2 in aqueous solution by a composite catalyst of Ag-rectorite. The catalysts were prepared via a novel thermal decomposition method followed after the cation-exchange process. The synthesized nano-materials were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) surface analyzer, Ultraviolet–visible light (UV–vis) absorption spectra, field-emission scanning electron microscope (FE-SEM) and transmission electron microscope (TEM). The different mechanisms of degradation process with or without visible light irradiation were discussed, respectively. Moreover, the degradation efficiency of 2,4-DCP wastewater under Ag-rectorite/H 2 O 2 /visible light system was investigated by series of experiments, concerning on effects of major operation factors, such as H 2 O 2 dosage and the initial pH value. The highest degradation rate was observed when adding 0.18 mL H 2 O 2 into 50 mL 2,4-DCP solution, and the optimal pH value was 4 for the reaction. Afterwards, total organic carbon (TOC) experiments were carried out to evaluate the mineralization ratio of 2,4-DCP.
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
PubMed
高影响因子
BULLETIN OF MATERIALS SCIENCE
·
2020
·Vol. 43
·期 1
·1-7
·
IF 1.392
Xiao Meng,Peng Yu,Pang Mengting,Hao Baicun,Wang Yujia,Zhang Yulian,Liao Yang,Mao Hui
Heterogeneous Pd catalysts were developed by immobilizing Pd nanoparticles (Pd NPs) onto plant polyphenol (bayberry tannin, BT) decorated γ-Al 2 O 3 . The abundant hydroxyls of plant polyphenols were capable of stabilizing the Pd NPs. Transmission electron microscopy observation confirmed that the Pd NPs with the diameter of 3.75 ± 0.5 nm were highly dispersed in the catalyst. The as-prepared Al 2 O 3 –BT–Pd catalysts were found to be highly active in mild hydrodechlorination (HDC) of 2,4-dichlorophenols (DCPs) using formic acid as a hydrogen source. The 2,4-DCPs were completely dechlorinated in 4 h at 30°C and under atmospheric pressure. During the catalytic HDC, the stabilizing capability of BT successfully prevented the leakage and aggregation of Pd NPs, thus ensuring a high cycling stability with stable and high catalytic activity. The Al 2 O 3 –BT–Pd catalysts were recycled six times, without obvious loss of activity. In the sixth cycle, the catalytic HDC yield still reached 98.29% under the same reaction conditions, superior to the control catalysts, including γ-Al 2 O 3 supported Pd NPs (Al 2 O 3 –Pd) and powdered activated carbon supported Pd NPs (AC–Pd). Furthermore, the Al 2 O 3 –BT–Pd also showed high activity in the mild catalytic HDC of 2,4,6-trichlorophenols and chlorobenzene derivatives. Our results demonstrated efficient catalysts to address the environmental issue of chlorophenol pollution.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Chang Zhou,Qiang Cao,Jia-Liang Wei,Jing-Hui He,Jian-Mei Lu
Soil contaminated by 2,4-dichlorophenol (2,4-DCP) is a substantial environmental concern because it poses severe health hazards. Fenton and Fenton-like oxidation in the removal of 2,4-DCP in soil has attracted considerable attention but suffers from low efficiency due to strong adsorption of pollutants by soil. In this study, the non-toxic catalyst (DFNS-Fe 2 O 3 ) was prepared by loading Fe 2 O 3 on dendritic fibrous nanosilica (DFNS) for degradation of 2,4-DCP in soil. DFNS-Fe 2 O 3 could rapidly remove 2,4-DCP within 120 min (98 %), and the removal rate maintained 70 % after 3 cycles of durability test. In addition, BPA, phenol and 2-CP could be efficiently degraded by DFNS-Fe 2 O 3 . •OH and •O 2 were the main reactive oxygen species (ROS) in the reaction. It is speculated that 2,4-DCP degrades through hydroxylation, substitution process according to the GC-MS results. The toxicity of 2,4-DCP and intermediate products were observed by Ecological Structure Activity Relationships Predictive Model program (ECOSAR). This work paves an avenue for rational design of heterogeneous catalyst on DFNS and their applications in chlorophenol contaminated soil.
研究领域:
环境科学
·
催化材料
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Minghui Wang,Mei Zhang,Zhuoyu Wen,Chaoqun Li,Shilin Zhao,Jun Ma,Yang Liao,Xiaoting Li
Chlorophenols have been frequently detected in the environment, posing potential threats to both the natural ecosystem and human health. Semiconductor photocatalytic degradation of chlorophenols has become a prominent research focus. However, the development of high-performance and stable photocatalysts remains challenging. In this work, the nitrogen-modified ceria (N-CeO 2 ) was optimally prepared by microwave-assisted method and utilized for photocatalytic degradation of 2,4-DCP. The CeO 2 photocatalyst with 10% nitrogen doping (10% N-CeO 2 ) prepared under the optimal condition (microwave power of 560 W for 2 min and calcination temperature of 400 °C for 2 h) degraded 2,4-DCP with the highest removal efficiency of 93.51%. It was identified that the optimally prepared 10% N-CeO 2 photocatalyst had the nanometer size with surface imperfections and increased BET surface, and showed strongest photocurrent response and lowest charge transfer resistance among all the prepared materials. Additionally, an analysis of the band gap structure revealed that the band gap of 10% N-CeO 2 decreased from 3.05 eV (for pure CeO 2 ) to 2.42 eV, resulting in enhanced light absorption capacity. The radical trapping experiments and electron paramagnetic resonance (EPR) proved that the active species contributed to the degradation of 2,4-DCP mainly as •OH, •O 2 - . The potential photocatalytic degradation mechanism of 2,4-DCP was a continuous dechlorination and hydroxylation process with complete mineralization of the pollutant to CO 2 and H 2 O. This work can provide a feasible way to prepare high-efficiency nitrogen-doped ceria photocatalysts with great potential for the removal of chlorophenols.
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
CHEMOSPHERE
·
2015
·
IF 3.34
Qiong Tan,Guiqiu Chen,Guangming Zeng,Anwei Chen,Song Guan,Zhongwu Li,Yanan Zuo,Zhenzhen Huang,Zhi Guo
Immobilized Phanerochaete chrysosporium loaded with TiO 2 nanoparticles (PTNs) are novel high-value bioremediation materials for adsorbing cadmium and for degrading 2,4-dichlorophenol (2,4-DCP). The real-time changes in H + and O 2 fluxes were measured using the noninvasive microtest technique (NMT). The H + influx increased after the addition of 2,4-DCP, and shifted to efflux following the addition of Cd 2+ . The O 2 flux decreased after the addition of both 2,4-DCP and Cd 2+ . A larger Cd 2+ flux was immediately observed after exposure to 0.5 mM Cd 2+ (−351.25 pmol cm −2 s −1 ) than to 0.1 mM Cd 2+ (−107.47 pmol cm −2 s −1 ). The removal of Cd 2+ by the PTNs increased more after treatment with the 0.5 mM exposure solution (27.6 mg g −1 ) than with the 0.1 mM exposure solution (3.49 mg g −1 ). The enzyme activities were analyzed to review the antioxidative defense system of PTNs in a solution containing various concentrations of Cd 2+ . The activities of the coenzyme nicotinamide adenine dinucleotide (NADH) oxidase as well as the enzyme catalase (CAT) plateaued at 6.5 U g −1 FW and 9.7 U g −1 FW, respectively, after exposure to 0.25 mM Cd 2+ . The activity of superoxide dismutase (SOD) increased gradually in solutions containing 0.1–0.6 mM Cd 2+ , and eventually reached a maximum (68.86 U g −1 FW). These results illustrate how the antioxidative defense system and the physiological fluxes of PTNs respond to the stress caused by toxic pollutants .
研究领域:
环境生物学
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微生物学
✓ 已验证
DOI
PubMed
高影响因子
LUMINESCENCE
·
2025
·Vol. 40
·期 4
·e70164
·
IF 3
Lin Zhou,Xuan Chen,Zhanghong Guo,Haining Cui,Jinxin Ma,Qijun Song
Metal nanoclusters (MNCs) have attracted widespread attention due to their unique subnanometer size, tunable fluorescence emission, and excellent biocompatibility. However, the enzyme-like activity and the optical properties of MNCs are rarely exploited simultaneously. Here, iridium nanoclusters (Py-IrNCs) with excellent fluorescence properties and the laccase-like activity were synthesized by the reduction of IrCl 3 with NaBH 4 in the presence of pyrogallol. The laccase activity of Py-IrNCs exhibited in the catalytic transformation of 2,4-dichlorophenol (2, 4-DP) is substantially superior to that of natural laccase, which is manifested by the fact that the amount of Py-IrNCs was only 2.5% of natural laccase to achieve the same catalytic performance. In the coexisting of 4-aminoantipyrine (4-AP), a distinct color change and quench of fluorescence were observed; thus, a sensitive colorimetric and fluorescence dual-mode determination of 2,4-DP was achieved with a linear range of 0–40 μM and a limit of detection of 0.5 μM. The dual-mode detections can be mutually verified, which effectively improved the reliability of the analysis, demonstrating a promising application potential of Py-IrNCs in pollutant determination.
研究领域:
分析化学
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环境科学
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纳米技术
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）