APPLIED CATALYSIS B-ENVIRONMENTAL
·
2023
·
IF 22.1
Jun Zhang,Songying Qu
Here we investigated the synergetic multiple free radicals (atomic hydrogen (H*), superoxide anion (•O 2 − ), and hydroxyl radicals (•OH)) in enhancing removal efficiencies of the halogen organic pollutants , such as p-chlorophenol (4-CP). A TiO 2 photoanode and a palladium and carbon layer co-modified Cu/Cu 2 O/CuO (Cu x O@C/Pd) photocathode were combined to construct a photoelectrocatalytic platform that enabled the synchronous production of multiple free radicals. It was found that the conversion and mineralization rates of 4-CP were up to ∼0.044 min −1 and ∼71.3% respectively, representing an increase of ∼4.3 times and ∼2.1 times compared to conventional •OH mediated oxidation . Theoretical calculations and experiments indicated that the conversion barrier of 4-CP was significantly reduced through the redox synergies of H* and •OH and the simultaneous nucleophilic-electrophilic addition of •O 2 − effectively inhibited the accumulation of benzoquinone intermediates. This work is beneficial for the study and application of advanced oxidation processes mediated by multiple free radicals.
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
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Juan Yang,Jingyi Hao,Siyu Xu,Jun Dai,Yan Wang,Xinchang Pang
In this study, Nb 2 O 5 nanorods/graphene composites (NbO NRs/GR) are prepared by one-pot alkaline hydrothermal process, utilizing the new roles of graphene oxide (GO) as the structure-directing and morphology-controlling agent for the growth of NbO NRs. Compared to blank NbO, NbO/GR composites exhibit significantly improved photocatalytic activity for 4-CP degradation under visible-light irradiation, although 4-CP and NbO do not absorb visible light themselves. The in-situ formation of surface complexes between 4-CP and NbO and the subsequent charge transfer based on LMCT mechanism can be responsible for the visible photocatalytic activity. And meanwhile, the photoelectrons transferred to GR surface from in-situ formed complex (NbO/4-CP) via NbO NRs can initiate the synergistic Cr(VI) reduction. The GR contents and NbO crystalline phase have great effects on the photocatalytic activity of NbO/GR composites toward simultaneous 4-CP degradation and Cr(VI) reduction. The amorphous NbO/GR composite with 4.0 wt% GR (NbO-400/GR-4.0%) shows the highest photocatalytic activity. The influences of various experimental conditions (including the surface fluorination of NbO/GR, the initial concentrations of 4-CP and Cr(VI), pH, reaction atmosphere, and adding radical scavengers) on the visible photocatalytic activities are investigated in detail. According to the catalytic activity, UV-vis DRS and FT-IR spectra of NbO/4-CP or NbO/GR/4-CP, and photocurrent response in aqueous 4-CP solution, the formation of the surface complex is evidenced and the visible-light catalytic mechanism based on LMCT process is proposed.
研究领域:
材料科学
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环境科学
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化学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2015
·Vol. 39
·期 8
·6474-6481
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IF 3.086
Yansheng Liu,Wei Zhang,Xinlin Li,Xuanduong Le,Jiantai Ma
In this study, Pd nanoparticles functionalized on the surface of a Fe3O4@SiO2@m-SiO2 nano-catalyst has been synthesised with accessible active sites and ultra-large surface areas. The Pd/Fe3O4@SiO2@m-SiO2 nano-catalyst can be recovered by applying an external magnetic field. The catalytic activity of Pd/Fe3O4@SiO2@m-SiO2 is tested in the catalytic reduction of 4-nitrophenol and the hydrodechlorination of 4-chlorophenol. The high catalytic activity is attributed to the well-dispersed Pd nanoparticles on the ultra-large surface of Fe3O4@SiO2@m-SiO2. Furthermore, the Pd/Fe3O4@SiO2@m-SiO2 nano-catalyst can be reused at least five times without significant loss in activity, which confirms its good stability. Therefore, the approach mentioned above that is based on core–shell structured magnetic Pd/Fe3O4@SiO2@m-SiO2 provides a useful platform for the fabrication of Pd NP based catalysts that feature easy accessibility, superior activity and convenient recovery.
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
JOURNAL OF HAZARDOUS MATERIALS
·
2019
·
IF 7.65
Meng Xie,Junchuan Tang,Guodong Fang,Mengping Zhang,Lingshuai Kong,Feng Zhu,Long Ma,Dongmei Zhou,Jinhua Zhan
The development of highly active and multifunctional carbocatalysts modified with heteroatoms or metal species is crucial for practical environmental remediation applications. In this study, nitrogen-doped porous carbon embedded with highly dispersed CoO nanodots (CoO-N-C) was successfully prepared from a biomass-derived Schiff base polymer for the first time. The morphology analysis shows that CoO nanodots were embedded in the N doped carbon layer with size of ∼6.5 nm. CoO-N-C catalyst exhibited excellent 4-CP adsorption efficiency as well as excellent catalytic performance in the activation of peroxymonosulfate (PMS) for 4-CP degradation. Total organic carbon (TOC) removal was close to 99.7% and involved a combination of adsorption and degradation processes. Singlet oxygen ( 1 O 2 ) was found to be the dominant oxidative species for 4-CP degradation. The underlying mechanism of these processes were elucidated, and it was found that the introduction of CoO nanodots in CoO-N-C not only enhanced radical catalytic processes, but also significantly enhanced the non-radical catalytic processes of PMS activation . This derived from the synergistic effect between the embedded CoO nanodots and doped nitrogen for the increase of electron density on carbon surface of catalyst, thereby accelerating the electron transfer process for PMS activation and improving the catalytic performance.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Tingting Zhang,Yanling Yang,Xing Li,Nan Wang,Hang Li,Peng Du,Haikuan Yu,Siyang Ji,ZhiweiZhou
In this study, an experimental study aimed at optimizing the factors affecting the regeneration amount of 4-chlorophenol (4-CP) from spent powdered activated carbon (PAC) is presented. For this response surface methodology (RSM) with Box-Behnken design was applied, which identified four variables (acoustic density, NaOH concentration, spent PAC dosage and ethanol concentration) in batch experiments. The physicochemical characteristics of the regenerated PAC under the optimal desorption condition was evaluated using thermogravimetric analysis, Fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET) and scanning electron microscopy, as compared with the virgin and spent PACs. Among the four variables, acoustic density and ethanol concentration (v/v, %) had stronger effect on the 4-CP desorption (p < 0.001). The predicted optimal 4-CP desorbing amount was 97.43 mg g –1 , and this matched well the observed performance of (96.94 ± 0.70) mg g –1 , obtained by acoustic density of 0.36 W mL –1 , NaOH concentration of 0.10 mol L –1 , spent PAC dosage of 0.93 g L –1 and ethanol concentration (v/v) of 24%. The result of thermogravimetric pyrolysis profiles of regenerated PAC confirmed that the adsorption behavior of 4-CP exhibited a chemisorption feature and desorption process was dominated by chemical reaction. Analysis of FTIR, pore structure and BET surface area demonstrated that ultrasound mainly acted on the surface functionalities, macro-pore and meso-pore structure of PAC. Additionally, the SEM images indicated that cavitation effect affected the surface roughness and surface cavities of PAC. The results here provided an insight into the application of ultrasound to regenerate saturated PAC with 4-CP.
研究领域:
环境工程
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吸附与再生
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水处理技术
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物理化学方法
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环境污染控制
✓ 已验证
DOI
高影响因子
Journal of Environmental Sciences
·
2013
·
IF 1.773
Kashif Naeem,Feng Ouyang
The photocatalytic degradation of phenol and 4-chlorophenol (4-CP) in aqueous suspensions with the use of titanium dioxide (TiO 2 ) under UV irradiation was examined. The effects of different supporting materials mixed physically with TiO 2 were studied to achieve maximum degradation efficiency. Among the three supports, namely activated carbon (AC), silica (SiO 2 ) and zeolite (ZSM-5), all exhibited paramount efficiency for degradation of phenol and 4-CP and was better than TiO 2 alone. The optimum concentration was found to be 50 mg for all supporting materials. The efficiency order of the three supports was as follows: AC > ZSM-5 > SiO 2 , respectively. Whilst, the degradation of phenol and 4-CP was improved from 70.6% to 87.6% and 80.6% to 89.7%, respectively, within 120 min photocatalysis in the presence of optimal amount of AC. The degradation was also comparatively enhanced in the presence of cheaper rice husk and the activity was closed to ZSM-5 and lower than AC.
研究领域:
环境科学
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化学工程
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2020
·
IF 7.864
Jie Miao,Wei Geng,Pedro J. J. Alvarez,Mingce Long
Nitrogen-doped carbon materials attract broad interest as catalysts for peroxymonosulfate (PMS) activation toward an efficient, nonradical advanced oxidation process. However, synthesis of N-rich carbocatalysts is challenging because of the thermal instability of desirable nitrogenous species (pyrrolic, pyridinic, and graphitic N). Furthermore, the relative importance of different nitrogenous configurations (and associated activation mechanisms) are unclear. Herein, we report a “coating-pyrolysis” method to synthesize porous 2D N-rich nanocarbon materials (PCN-x) derived from dopamine and g-C3N4 in different weight proportions. PCN-0.5 calcined at 800 °C had the highest surface area (759 m2/g) and unprecedentedly high N content (18.5 at%), and displayed the highest efficiency for 4-chlorophenol (4-CP) degradation via PMS activation. A positive correlation was observed between 4-CP oxidation rates and the total pyridinic and pyrrolic N content. These N dopants serve as Lewis basic sites to facilitate 4-CP adsorption on the PCN surface and subsequent electron-transfer from 4-CP to PMS, mediated by surface-bound complexes (PMS–PCN-0.5). The main degradation products were chlorinated oligomers (mostly dimeric biphenolic compounds), which adsorbed to and deteriorated the carbocatalyst. Overall, this study offers new insights for rational design of nitrogen-enriched carbocatalysts, and advances mechanistic understanding of the critical role of N species during nonradical PMS activation.
研究领域:
环境科学
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催化材料
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2013
·
IF 3.498
Junling Zhang,Gang Chen,Miaomiao Tian,Ruigang Li,Xinjun Quan,Qiong Jia
γ-Alumina nanoparticles (γ-Al 2 O 3 ) were introduced to the conventional poly(methacrylic acid- co -ethylene glycol dimethacrylate) (MAA- co -EGDMA) monolith to prepare a novel organic-inorganic hybrid monolith, poly(MAA- co -EGDMA)-Al 2 O 3 monolith. The polymerization was induced in-situ with UV irradiation in an ultraviolet transparent polymethyl methacrylate (PMMA) microfluidic chip. The monolith-based solid phase microextraction system was used for the on-line determination of 2-amino-4-chlorophenol (ACP) in chlorzoxazone tablets coupled with an optical fiber spectrophotometer. Several parameters affecting the adsorption/desorption, including sample pH value, sample flow rate , sampling time, eluent flow rate, and eluting time, were investigated in detail. Under the optimized conditions, limit of detection (LOD) and limit of quantification (LOQ) of the method were calculated to be 2.8 and 9.1 µg L −1 , respectively, with the relative standard deviation (RSD) of 3.1%.
研究领域:
分析化学
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药物分析
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2017
·
IF 6.065
Rui Luo,Chao Liu,Jiansheng Li,Jing Wang,Xingru Hu,Xiuyun Sun,Jinyou Shen,Weiqing Han,Lianjun Wang
A new catalyst system of CoP/peroxymonosulfate (PMS) is presented, which achieved significant improvement in catalytic activity. Nanostructured CoP, obtained by a simple solid-state reaction, exhibited dramatic catalytic activity with 97.2% degradation of orange II of 100 ppm within 4 min. Moreover, the high efficiency could be reached for other phenolic pollutants, i.e., phenol and 4-chlorophenol. The reaction rate is much higher than the most reported catalysts. Effect of parameters on catalytic activity of the catalyst was studied in detail. Notably, initial pH of the solution had a slight negative effect on the catalytic performance over the pH range 4.07–10.92, suggesting that CoP has the great adaptability of pH. CoP/PMS demonstrated excellent anti-interference performance toward anions (Cl − , NO 3 − , and HCO 3 − ). In addition, the pathway of degradation of orange II is proposed by analyzing its intermediates. Based on the XPS spectra of CoP, the identification of the reactive species ( OH and SO 4 − ) by electron paramagnetic resonance (EPR) analysis and quenching tests, a possible mechanism for activation of PMS by CoP was proposed. Considering the dramatic catalytic activity, a wide range of pH catalyst suited, CoP is believed to provide robust support for the promising industrial application of AOPs.
研究领域:
环境科学
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催化
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水处理
·
污染物降解
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2020
·
IF 5.065
Lili Zhang,Yigang Ding,Bingwen Long,Lin Yao,Haiyuan Yuan,Yafen Dai
In this work, polymeric ionic liquids (PILs) based on imidazolium ionic liquid monomer , which possessed hierarchical porous structure and rich Lewis basic sites, could effectively adsorb both large-sized and small molecular phenolic compounds from aqueous solution. The maximum adsorption capacities of the as-synthesized PILs for tannic acid (TA), 4-nitrophenol (4-NP) and 4-chlorophenol (4-CP) reached as high as 911 mg/g, 460 mg/g and 433 mg/g, respectively. The capacity for TA was the highest among the existing adsorbents. The abundant Lewis basic sites (N-atom and Cl − ) provided by imidazolium ionic liquids and the special hierarchical porous structure of PILs were responsible for its excellent phenolic adsorption performance. The adsorption equilibrium data of 4-NP and 4-CP fitted well with the Freundlich model while those of TA complied better with the Langmuir model. The mechanism analysis indicated that the adsorption for 4-NP and 4-CP was mainly due to π–π interactions, and that for TA was dominated by H-bonding and electrostatic interaction. The PILs could be easily regenerated. This study provided a novel material for the treatment of phenolic wastewater.
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
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2022
·
IF 24.319
Shizong Wang,Jianlong Wang
This study prepared the carbon-supported cobalt catalyst (Co-C-X) for activating peroxymonosulfate (PMS), and investigated the effect of co-pyrolysis temperature of graphitic carbon nitride (g-C 3 N 4 ) and vitamin B 12 on the catalytic activity. It was found that with the increase of co-pyrolysis temperature, the catalytic activity of Co-C-X increased, due to the different coordination structures of cobalt. At 500 °C (Co-C-500), cobalt existed as CoO; while it was single atom Co at 600 °C (Co-C-600); and small size CoO at 700 °C (Co-C-700). Co-C-X could activate PMS to produce hydroxyl radicals, sulfate radicals, high-valent cobalt-oxo and singlet oxygen, which depended on the pyrolysis temperature. Although Co-C-700 had the highest catalytic activity, the leaching cobalt was also highest (3.23 mg/L), compared with that of Co-C-500 (0.27 mg/L) and Co-C-600 (0.14 mg/L). Co-C-600 had fast degradation for atrazine, nitrobenzene , bisphenol A, phenol and 4-chlorophenol, which also had wide pH range and high tolerance to inorganic ions.
研究领域:
催化
·
环境科学
·
材料科学
·
化学工程
✓ 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）