CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Jingjing Ren,Liuchun Zheng,Yaoming Su,Peipei Meng,Qianya Zhou,Hao Zeng,Tao Zhang,Huajian Yu
In order to treat heavy metal pollutants in acid mine drainage, zero-valent iron/phosphoric titanium dioxide (PTO-3nZVI and PTO-nZVI) was developed with phosphoric acid treatment and loading of zero valent iron and showed excellent adsorption of heavy metals. PTO-3nZVI and PTO-nZVI greatly improved the adsorption capacity for the targeted heavy metal Cd(II) (308 mg·g −1 for PTO-3nZVI and 206 mg·g −1 for PTO-nZVI) through complexation and coprecipitation. Additionally, competitive adsorption occurred between Cd(II) and coexisting heavy metal ions (Pb(II) and Cu(II)), resulting in different adsorption effects for PTO-3nZVI and PTO-nZVI, and their adsorption efficiencies decreased in the order Cu(II) > Pb(II) > Cd(II) for PTO-3nZVI and Pb(II) > Cu(II) > Cd(II) for PTO-nZVI. Based on these two aspects, X-ray photoelectron spectrometer (XPS) analyses and Density Functional Theory (DFT) calculations were used to characterize the adsorption behaviors of PTO-3nZVI and PTO-nZVI. In particular, competitive relationships for different heavy metals were clearly revealed by binding energies, Frontier Molecular Orbitals (FMOs) analyses, electrostatic potentials, and total potential and differential charge analyses of adsorption sites, binding sites and binding strengths.
研究领域:
环境科学
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材料化学
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重金属修复
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计算化学
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水处理
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高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
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2025
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IF 0
Maqinana Siphosethu,Kowenje Chrispin B. O.,Ojwach Stephen O.
Reactions of N 1 ,N 3 -bis(2-mercaptoethyl)isophthalamide with (3-aminopropyl)triethoxysilane (3-APTES) afforded the the corresponding Schiff base chelating ligand, (1Z,3Z)-N 1 ,N 3 -bis(2-mercaptoethyl)-N' 1 ,N' 3 bis(3(triethoxysilyl)propyl) isophthalimidamide ( L1 ) in high yields. Subsequent immobilization of L1 on mesoporous silica supports (SBA-15 and MCM-41) following a divergent method produced the respective fabricated L1@SBA-15 and L1@MCM-41 materials. Characterization of the fabricated chelating agents was accomplished using SEM, TEM, EDX, BET, PXRD, FT-IR, and TGA-DTA/DSC techniques. The fabricated materials were used as adsorbents for the removal of Cd(II), Pb(II) and Cr(VI) metal ions from water. Both the L1@SBA-15 and L1@MCM-41 materials demonstrated high extraction efficiencies for Cd(II) and Pb(II) cations, achieving over 98% and 97% removal, respectively, across a broad pH range (3–9). For Cr(VI) anions, relatively lower optimal extraction efficiencies of 67% and 77% were recorded between pH 3–12, for L1@SBA-15 and L1@MCM-41 , adsorbents, respectively. Faster extraction kinetics were observed for Cd(II) and Pb(II) cations, with over 94% removal achieved within 30 min, even at low initial metal concentrations (5 ppm) and adsorbent dosages (10 mg). Kinetic modelling showed that the adsorption process followed a pseudo -second-order kinetics, with high correlation coefficients (R 2 ) for Cd(II), Pb(II), and Cr(VI) of 0.97573, 0.97348, and 0.91017 using L1@MCM-41 , and 0.9754, 0.97089, and 0.89411 using L1@SBA-15 , respectively. Equilibrium data best fitted the Freundlich isotherm model, with R 2 values of 0.97952, 0.99892, and 0.97374 for L1@SBA-15 and 0.99879, 0.99999, and 0.90923 for L1@MCM-41 , corresponding to Cd(II), Pb(II), and Cr(VI), respectively. In competitive metal ion systems, the extraction selectivity followed the order Cd(II) > Pb(II) > Cr(VI), with L1@SBA-15 exhibiting superior overall performance compared to L1@MCM-41 . The extraction mechanism was postulated to occur through the coordination of the metal ions to the nitrogen/sulfur donor atoms in the chelating agents, consistent with the hard and soft acid and base (HSAB) principle. Furthermore, L1@MCM-41 demonstrated notable regeneration potential, retaining Cr(VI) extraction efficiencies over four successive cycles. Graphical
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DOI
PubMed
CELLULOSE
·
2022
·Vol. 29
·期 13
·7225-7249
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IF 6.123
Tang Rui,Zhang Hanbing,Muhammad Yaseen,Lu Caimei,Liu Kun,Yu Sishan,Tong Zhangfa
Magnetic bentonite (MB) is a cheap, effective and recyclable adsorbent for the removal of many pollutants. However, further enhancing the adsorption performance of pristine MB and eliminating the instability of Fe 3 O 4 magnetic particles in MB are vital and urgent for practical applications. Based on the principles of washing mesh bag and octopus tentacle, mesh-bag-like modifiers with tentacle-like structure of octopus were synthesized via grafted reaction of polyethylenimine (PEI) and carboxymethyl cellulose (CMC) to cover MB. As compared with the pristine MB, CMC-MB and PEI-MB, the magnetic bentonite adsorbent co-modified by PEI and CMC (CMC/PEI-MB) exhibited more multi-adsorption sites, stronger capture effects of tentacle for heavy metals and more effective mesh-bag-protection for Fe 3 O 4 . Attributed to these fascinating properties, CMC/PEI-MB achieved faster adsorption rates (the values of k 2 of Pb(II) and Cd(II) were 73.0 g mg ‒1 min ‒1 and 17.4 g mg ‒1 min ‒1 ) and elevated adsorption capacities (760 mg g ‒1 and 470 mg g ‒1 ) for 1500 mg L ‒1 Pb(II) and 1000 mg L ‒1 Cd(II) in a wider pH range (3–7). Moreover, the reutilization rate of Pb(II) and Cd(II) over CMC/PEI-MB still remained 90% after five successive recycles. XRD and FT-IR results indicated that the structure of CMC/PEI-MB was well persevered after desorption, and the corresponding maximum desorption capacities of Pb(II) and Cd(II) from CMC/PEI-MB were 624 mg g ‒1 and 362 mg g ‒1 within 1 h, respectively. The findings of this study provide an interesting and effective approach for the construction of superior adsorbents basing on customary phenomena for the remediation of heavy metals from wastewater. Graphical Abstract
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高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2016
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IF 3.782
Zhuo Guo,Dong-di Li,Xian-ke Luo,Ya-hui Li,Qi-Nai Zhao,Meng-meng Li,Yang-ting Zhao,Tian-shuai Sun,Chi Ma
The reduced graphene oxide (RGO) and Chitosan (CS) hybrid matrix RGO-CS were coated onto the glassy carbon electrode (GCE) surface, then, poly- l -lysine films (PLL) were prepared by electropolymerization with cyclic voltammetry (CV) method to prepare RGO-CS/PLL modified glassy carbon electrode (RGO-CS/PLL/GCE) for the simultaneous electrochemical determination of heavy metal ions Cd(II), Pb(II) and Cu(II). Combining the advantageous features of RGO and CS, RGO and CS are used together because the positively charged CS can interact with the negatively changed RGO to prevent their aggregation. Furthermore, CS has many amino groups along its macromolecular chains and possessed strongly reactive with metal ions. Moreover, PLL modified electrodes have good stability, excellent permselectivity, more active sites and strong adherence to electrode surface, which enhanced electrocatalytic activity . The RGO-CS/PLL/GCE was characterized voltammetrically using redox couples (Fe(CN) 6 3−/4− ), complemented with electrochemical impedance spectroscopy (EIS). Differential pulse anodic stripping voltammetry (DPASV) has been used for the detection of Cd(II), Pb(II) and Cu(II). The detection limit of RGO-CS/PLL/GCE toward Cd(II), Pb(II) and Cu(II) is 0.01 μg L −1 , 0.02 μg L −1 and 0.02 μg L −1 , respectively. The electrochemical parameters that exert influence on deposition and stripping of metal ions, such as supporting electrolytes , pH value, deposition potential, and deposition time, were carefully studied.
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PubMed
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
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2024
·Vol. 171
·期 2
·027511
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IF 3.1
Weiming Zhang,Peng Huang,Xinyu Lu,Tao Chen,Xuemin Duan,Yangping Wen,Liping Deng,Jingkun Xu
It's very essential to exploit a portable wireless integrated sensing platform for field simultaneous, on-site detection of heavy metal ions pollution that has been exhibited to Serious ecological and health risks even under trace levels, including Cd (II) and Pb (II) ions. In this work, we developed a portable sensing platform, consisting of an integrated screen-printed electrode (SPE) with the calcium/aluminum-layered double hydroxide (CaAl-LDH) nanocomposite based on carboxyl functionalized multi-walled carbon nanotubes (MWCNTs-COOH), a hand-held wireless electrochemical potentiostat and a tablet with a specially designed app, for field simultaneous rapid detection of both Cd (II) and Pb (II) in water environmental sample. The CaAl-LDH was produced through a facilely hydrothermal method, and the CaAl-LDH nanocomposite with MWCNTs-COOH was prepared by a one-step ultrasonic route, which demonstrated superior sensing performance for simultaneous determination of both Cd (II) and Pb (II) with a broad detection range (2–250 μg L−1 for Cd (II) and 5–250 μg L−1 Pb (II)) and low limit of detection (LOD) (0.96 μg L−1 Cd (II) and 0.74 μg L−1 for Pb (II)).Furthermore, the proposed tablet-operated portable wireless sensing platform was utilized for detection of both Cd (II) and Pb (II) in farmland irrigation canals with acceptable recoveries.
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高影响因子
NEW JOURNAL OF CHEMISTRY
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2019
·Vol. 43
·期 30
·12126-12136
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IF 3.069
Lingzhe Suo,Jing Zhao,Xinyi Dong,Xun Gao,Xinzhu Li,Jianfeng Xu,Xiumei Lu,Longshan Zhao
A novel polyaniline–polypyrrole functionalized SiO2-coated magnetic graphene oxide composite (MGO/SiO2@PANI–PPy) was prepared as a new magnetic solid-phase extraction (MSPE) adsorbent for separation and pre-concentration of chromium (Cr) and lead (Pb) at trace levels in food and environmental water samples followed by the use of inductively coupled plasma mass spectrometry (ICP-MS). Fourier transform infrared (FTIR) spectroscopy, vibrating sample magnetometry (VSM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) were used to characterize the nanocomposite. Various parameters affecting the extraction yield of heavy metals were optimized using a Box–Behnken design (BBD) through the response surface methodology (RSM). Under optimum conditions, the limits of detection (LODs) were 4.808 ng L−1 for Cr(III) and 3.401 ng L−1 for Pb(II) with relative standard deviations (RSDs) of less than 5% (n = 6). Furthermore, the maximum adsorption capacities of this new sorbent were 188.9 and 213.3 mg g−1 for Cr(III) and Pb(II), respectively. Finally, the developed method was successfully applied for determination of trace Cr(III) and Pb(II) in rice, milk, wine and environmental water samples with recoveries within 95.4–105%.
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高影响因子