Journal of Building Engineering
·
2024
·
IF 6.7
Baomin Wang,Weigao Ding,Chengcheng Fan,Fei Liu,Wenxin Lu,Haoxiang Yang
C-S-H gel is a complex cementitious system, and the properties present significant difference with various Ca/Si ratios. The immobilization mechanism of three heavy metals in C-S-H gel at various Ca/Si ratios was investigated in this work from the prospect of the physical adsorption and chemical immobilization. Results showed that higher Ca/Si ratios can result in an increase in silicon chain polymerization, and lower BET specific area, and C-S-H gel with various Ca/Si ratios showed the excellent immobilization for heavy metals. Pb(II) and Zn(II) can form hydroxyl complex polyhedra in C-S-H under strongly alkaline environments, and increase the silicon chain polymerization degree similar to the doping of C-S-H gel by Al. However, Cd(II) was immobilized in the C-S-H gel with the formation of a solid solution under the action of ion exchange with Ca(II), rather than in the form of hydroxyl complex polyhedral and cadmium hydroxide coprecipitates. The highest adsorption capacity of Pb(II) was realized in C-S-H gel with a Ca/Si molar ratio of 0.9, reaching 95.6006 mg/g. Pb(II) was mainly immobilized in C-S-H gel via physical and chemical adsorption, and the effect of chemical adsorption tended to be significant as the Ca/Si molar ratio increased. And the formation of Pb 8 Ca(Si 2 O 7 ) 3 can be detected in C-S-H gel with a higher Ca/Si molar ratio.
研究领域:
材料科学
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环境科学
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高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2018
·
IF 4.005
Zhongbo Shang,LiWen Zhang,Xuyang Zhao,Shanhu Liu,Deliang Li
A low-cost mercapto-modified coal gangue (CG-SH) was fabricated by modification of coal gangue (CG) with (3-mercaptopropyl) trimethoxysilane. The structure and composition for as-prepared CG-SH were characterized by using X-ray diffraction (XRD), Fourier transfer infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray fluorescence (XRF). Results indicated that larger amounts of mercapto-groups (-SH) was successfully introduced onto CG, which followed by acted as active sites for the removal of heavy metal cations, such as Pb(II), Cd(II) and Hg(II). The factors that affected the adsorption equilibrium as well as the removal efficiency, i.e., contact time, initial concentration, pH and temperature, were investigated in detail. The adsorption isotherms for Pb(II), Cd(II) and Hg(II) were well fitted with Langmuir model. The maximum adsorption capacity of CG-SH for Pb(II), Cd(II) and Hg(II) were calculated to be 332.8, 110.4 and 179.2 mg g −1 , respectively. The adsorption for Pb(II), Cd(II) and Hg(II) on CG-SH could be well described by pseudo-second-order kinetic model . And thermodynamic analysis suggests that the adsorption process for Pb(II) is exothermal, while that for Cd(II) and Hg(II) are endothermal. The results suggest CG-SH have great potential to be used as efficient absorbent for the removal of heavy metal cations from water.
研究领域:
环境科学
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材料科学
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PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2025
·
IF 7.3
Yantian Ji,Duo Xu,Shuangyun Bai,Bowen Du,Hongyang Chen,Tiecheng Wang,Xianqiang Yin
Discharge plasma is gaining increasing attention in environmental science due to its advanced oxidative properties. While discharge plasma is capable of degrading most of the pollutants in contaminated water, it is not effective in degrading the accompanying microplastics (MPs). Notably, residual MPs in plasma-treated water may become carriers of other pollutants in the environment. The adsorption and co-transport behaviors of two MPs with Cd(II), before and after Dielectric Barrier Discharge (DBD) plasma treatment, were examined via batch and column experiments. The results showed that plasma-treated MPs exhibited significantly enhanced adsorption capacity for Cd(II), attributed to grafted polar functional groups on their surfaces. Density Functional Theory (DFT) calculations revealed that the enhancement resulted from reduced steric hindrance, along with stronger hydrogen bonding and van der Waals interactions. Co-transport experiments revealed that plasma treatment significantly promoted the carrier role of MPs in facilitating Cd(II) transport. Specifically, plasma-treated MPs mitigated Cd(II) deposition at the column base under favorable conditions for transport. Derjaguin–Landau–Verwey–Overbeek (DLVO) theory provided a satisfactory explanation for the observed transport behaviors of plasma-treated MPs and Cd(II). These findings highlight the potential environmental risks posed by plasma-treated MPs as carriers of Cd(II) and the need for further studies on their long-term ecological impacts.
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高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2021
·Vol. 96
·期 8
·2382-2389
·
IF 3.174
Jianxin Tang,Jianmin Huang,Thein Tun,Sihua Liu,Jue Hu,Guiyin Zhou
BACKGROUND At present, various kinds of hydrogel adsorbents are applied to the treatment of heavy metal ions in wastewater. In this work, we focused on the adsorption of cadmium [Cd(II)] and copper [Cu(II)] onto microspheres of a novel thermosensitive hydrogel (NH 2 -SA/PNIPA, aminated sodium alginate/poly- N -isopropyl acrylamide), studied the effect of temperature on the phase transition of the hydrogel in detail, and discussed the influence on the adsorption behavior of metal ions in the hydrogel. RESULTS The NH 2 -SA/PNIPA exhibited a higher adsorption efficiency under the conditions of interfering monovalent cationic and neutral pH. The adsorption capacities based on the Langmuir model were 57.2 mg g –1 for Cu(II) and 100.5 mg g –1 for Cd(II) at 20 °C, respectively. Higher temperature facilitated the adsorption process and also led to the volume shrinkage and hydrophobicity of NH 2 -SA/PNIPA. The metal ions had different hydration and hence different adsorption capacities, of 56.7 mg g –1 for Cu(II) and 88.6 mg g –1 for Cd(II) at 40 °C. The results of diffusion behavior analysis showed that the diffusion coefficients were ≈1 × 10 −11 m 2 s –1 . The adsorption performance of NH 2 -SA/PNIPA hardly decreased even after five cycles. In addition, the adsorption process was controlled mainly by the complexation reaction. CONCLUSION The novel hydrogel microspheres overcame the deficiency of conventional adsorbents and possessed high diffusibility. This work provides a theoretical basis and empirical evidence for enhancement of adsorbents for removing heavy metals in wastewater. © 2021 Society of Chemical Industry (SCI).
研究领域:
环境科学
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材料科学
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高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Bao-Lin Zhang,Wei Qiu,Pan-Pan Wang,Yu-Lei Liu,Jing Zou,Lu Wang,Jun Ma
This study examined the effects of two kinds of iron-trimesic metal-organic frameworks (MOFs) [MIL-100(Fe) and Fe-BTC] on adsorption of Pb(II) and Cd(II). For both materials, adsorption of Pb and Cd nearly approached equilibriums in the initial 2 min with high pseudo-second-order kinetics rate constants (0.895 g·mg −1 ·min −1 for Pb and 1.416 g·mg −1 ·min −1 for Cd). Both materials showed better adsorption performance with the increase of solution pH (from 2 to 7). Adsorption processes were endothermic, entropy-increased and spontaneous. The higher enthalpy change ( Δ H 0 ) and entropy change ( Δ S 0 ) values for Cd adsorption reflected the more difficult adsorption of Cd compared with Pb, which is related with more negative hydration enthalpy ( Δ H hyd Θ ) and larger ionic radius of Cd. Multilayer adsorption phenomena appeared with no maximum adsorptive capacity observed. Both Langmuir-Freundlich and Freundlich-BET models could well describe isotherms. Multilayer adsorption may be attributed to the formation of inner-sphere complexation and outer-sphere complexation. Bockris-Devanathan-Muller (BDM) electrical double layer theory was used for illustrating adsorption mechanism. The fixed-bed adsorption experiments with Fe-BTC showed outstanding elimination performance in initial operating period (>99.8% for Pb and >99.6% for Cd), with effective filtration volume of 980 mL for Pb and 300 mL for Cd. Recyclability test showed that Fe-BTC could be well regenerated by ethylenediamine tetraacetic acid disodium salt (EDTA-2Na). This study showed that MIL-100(Fe) and Fe-BTC are potential for practical heavy metal removal applications.
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 Cleaner Production
·
2018
·
IF 5.651
Peng Liu,Yining Gao,Fazhou Wang,Lu Yang
Heavy metal contamination is an important environmental issue . Heavy metal removal by cementitious materials would be an efficient method because of their large-scale exposure to rainwater and groundwater. In this study, 3-thiocyanatopropyltriethoxysilane (TCPS)-modified Fly ash (T-FA) beads were prepared and incorporated into pervious concrete . The functionalized pervious concrete was used to sequester Cd (II) from solution, utilizing the chelating property of the thiocyanate on TCPS. TCPS molecules were chemically bonded onto FA beads after alkali activation , which was confirmed by IR spectroscopy. IR shows the vibration of Si OH and the asymmetric vibrations of CH 2 and CN on TCPS. In addition, 29 Si NMR spectroscopy identifies a new peak at −47.22 ppm assigned to T 2 [RSi(OSi) 2 OH]. T-FA beads can efficiently remove Cd (II) when immersed and stirred in a CdCl 2 solution. An equally significant sequestration capacity was demonstrated when T-FA beads were incorporated in pervious concrete. Cd (II) concentrations were reduced from 300 to 15.86 ppm when a 100 × 100 × 100 mm 3 T-FA-loaded concrete specimen was exposed to a 5 L CdCl 2 solution.
研究领域:
环境科学
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材料科学
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高影响因子
RSC Advances
·
2017
·Vol. 7
·期 59
·36929-36934
·
IF 3.108
Danfeng Qin,Ruiyu Xu,Hangjia Shen,Xamxikamar Mamat,Le Wang,Shanshuang Gao,Ying Wang,Nuerbiya Yalikun,Thomas Wagberg,Shiguo Zhang,Qunhui yuan,Yongtao Li,Guangzhi Hu
Nitrogen-doped mesoporous carbon (NMC) derived from a single small-molecule protic salt (p-phenylenediamine bisulfate) is used for sensing toxic heavy metal ions. Using Nafion, bismuth and NMC to anchor the glassy carbon electrode surface, the fabricate electrode shows high sensitivity for detecting Cd(II) and Pb(II). The limits of detection (S/N = 3) are estimated to be 0.3 μg L−1 for Cd(II) and 0.4 μg L−1 for Pb(II), respectively, which are 10 and 25 times lower than the maximum acceptable content for drinking water recommended by the WHO. Furthermore, the sensor is successfully used to analyze Cd(II) and Pb(II) in tap-water with high anti-interference capability and good recovery.
研究领域:
材料科学
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环境科学
·
分析化学
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高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2017
·Vol. 24
·期 29
·23144-23152
·
IF 2.741
Wang Li,Lu Yixin,Yang Chen,Chen Chengyu,Huang Weilin,Dang Zhi
The stability of nanoparticles (NPs) in aquatic environments is important to evaluate their adverse effects on aquatic ecosystems and human health. Nanoparticle stability is known to be influenced by coexisting ions and dissolved organic matter. This study was designed to investigate the effects of coexisting low-level Cd(II) on the stability of humic acid-coated nano-TiO 2 (HA-TiO 2 ) particles in aquatic environments by measuring their aggregation kinetics through time-resolved dynamic light scattering (DLS) and monitoring suspended HA-TiO 2 concentrations via optical absorbance changes over time. The particles exhibited aggregation behavior consistent with the classic Derjaguin–Landau–Verwey–Overbeek (DLVO) theory. The results showed that Cd(II) concentration, pH, and ionic strength had various effects on the aggregation kinetics of the HA-TiO 2 NPs. The HA-TiO 2 particles aggregated faster as the Cd(II) concentration increased whereas the stability of the nanoparticles increased as the solution pH increased or ionic strength decreased regardless of the Cd(II) concentration. At the fixed pH and ionic strength conditions, the addition of Cd(II) promoted aggregation of nanoparticles, leading to higher attachment efficiencies. The enhanced aggregation of the HA-TiO 2 NPs in the presence of coexisting cadmium ions in aqueous solutions indicated that the fate and transport of nanoparticles could be greatly affected by heavy metals in aquatic environments.
研究领域:
环境科学
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毒理学
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PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2023
·
IF 13.6
Haoran Tian,Shuchuan Peng,Lu Zhao,Yihan Chen,Kangping Cui
Biochar-supported zero-valent iron nanocomposites have received much attention due to their application potential in environmental pollution remediation. However, in many occasions, zero-valent iron loading improves the electron transfer efficiency and catalytic oxidation capacity of biochar while blocking the original pore structure of biochar, limiting its application potential. In this study, a zero-valent iron composites with large SSA (865.86 m 2 /g) was prepared in one step using pre-pyrolysis of biochar powder and K 2 FeO 4 grinding for co-pyrolysis. The processes of ZVI generation and SSA expansion during the pyrolysis were investigated. The factors affecting the removal process of Cd and OTC in water by the composites were investigated. The mechanisms of Cd fixation and OTC degradation by the composites were explored by experiments, characterization, and DFT calculations. The OTC degradation pathway was proposed by theoretical predication and LC-MS spectrometry . The results indicate that ion exchange, complexation with oxygen-containing functional groups, electrostatic attraction, and interaction with π-electrons are the main mechanisms of Cd immobilization. The degradation pathways of OTC mainly include dehydroxylation , deamination and dealkylation.
研究领域:
环境科学
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材料科学
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PubMed
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2023
·
IF 4.3
Dian-Bing Zhou,Hai-Tao Zhu,Yu-Zhu Hou,Gui-Lan Shen,Can Shi,Ya-Jie Zhu,Ya-Bing Xiao,Wei Song,Yu-Xin Liu,Fang Han,Ping Zheng,Xiao-Feng Yu
The conventional method for the determination of heavy metals in food is acid digestion followed by atomic absorption spectrometry or induced coupled plasma mass spectrometry . However, for high salt foods, due to the strong matrix effect, the detection results are seriously inaccurate. In this work, sulfur-functionalized magnetic metal-organic frameworks (Fe 3 O 4 @UiO-66-SH) were synthesized by coating Fe 3 O 4 nanospheres with sulfydryl-functionalized UiO-66. The Fe 3 O 4 @UiO-66-SH possesses both the magnetic properties of Fe 3 O 4 and the diverse properties of metal-organic framework (MOF) in one material, which has the superiority of high surface area, easy-operation and strong adsorb ability with Pb (II) and Cd(II), is used to separate and determine Pb (II) and Cd(II) in high salt foods by magnetic solid phase extraction-induced plasma mass spectrometry. The detection limits (LODs) for Pb (II) and Cd(II) were 0.17 and 0.21 µg/kg, respectively, and the quantification limits (LOQs) were 0.56 and 0.66 µg/kg. Analyzing the certified reference material of soy sauce (CFAPA-QC1728–4, P41839) and estimating the spiked recoveries proved the accuracy and precision of the proposed method. The determined values agreed well with the reference values, and the recoveries for spiking sample varied from 85.8–100.5%.
研究领域:
分析化学
·
食品安全
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DOI
高影响因子
TALANTA
·
2018
·
IF 4.244
Xiaorong Gan,Huimin Zhao,Kwok-Yin Wong,Dang Yuan Lei,Yaobin Zhang,Xie Quan
Surface functionalization is an effective strategy in the precise control of electronic surface states of two-dimensional materials for promoting their applications. In this study, based on the strong coordination interaction between the transition-metal centers and N atoms, the surface functionalization of few-layer MoS 2 nanosheets was successfully prepared by liquid phase exfoliation method in N, N-dimethylformamide (DMF), 1-methyl-2-pyrrolidinone, and formamide . The cytotoxicity of surface-functionalized MoS 2 nanosheets was for the first time evaluated by the methylthiazolyldiphenyl-tetrazoliumbromide assays. An electrochemical sensor was constructed based on glass carbon electrode (GCE) modified by MoS 2 nanosheets obtained in DMF, which exhibits relatively higher sensitivity to Cd 2+ detection and lower cytotoxicity against MCF-7 cells. The mechanisms of surface functionalization and selectively detecting Cd 2+ were investigated by density functional theory calculations together with various spectroscopic measurements. It was found that surface-functionalized MoS 2 nanosheets could be generated through Mo-N covalent bonds due to the orbital hybridization between the 5 s orbitals of Mo atoms and the 2p orbitals of N atoms of the solvent molecules. The high selectivity of the sensor is attributed to the coordination reaction between Cd 2+ and O donor atoms of DMF adsorbed on MoS 2 nanosheets. The robust anti-interference is ascribed to the strong binding energy of Cd 2+ and O atoms of DMF. Under the optimum conditions, the electrochemical sensor exhibits highly sensitive and selective assaying of Cd 2+ with a measured detection limit of 0.2 nM and a linear range from 2 nM to 20 μM.
研究领域:
材料科学
·
分析化学
·
生物医学
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DOI
PubMed
高影响因子
CLEAN-Soil Air Water
·
2026
·Vol. 54
·期 1
·e70109
·
IF 1.4
Yun Xing,Xiangfei Zhang,Yuqi Zhou,Jingjing Guo,Yuan Huang,Xiaohan Xu,Jiankun Li,Dingyu Wang
The disposal of spent coffee grounds (SCG) not only represents a significant waste of resources but also poses environmental challenges, highlighting the need for effective pretreatment strategies to mitigate potential adverse effects. Incorporating metal oxides into biomass-based adsorbents can enhance their adsorption capacity for heavy metal ions by enhancing electrostatic attraction and increasing the number of accessible active sites. In this study, KMnO 4 -modified spent coffee grounds (KMnO 4 -SCGS) were successfully synthesized and applied for the removal of Cd(II) from aqueous solution. Key process parameters, including contact time, pH, initial Cd(II) concentration, temperature, and adsorbent dosage, were systematically investigated. Characterization using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and x-ray photoelectron spectroscopy (XPS) confirmed that KMnO 4 treatment increased the abundance of oxygen-containing functional groups and promoted the deposition of manganese oxides (MnO x ) on the adsorbent surface. The adsorption isotherm followed the Langmuir model, and the kinetics were well fitted by the pseudo-second-order model. The maximum Langmuir adsorption capacity of KMnO 4 -SCGS for Cd(II) was determined to be 49.54 mg/g at pH 5.0, and 298 K. Thermodynamic analysis indicated that the adsorption process was spontaneous and endothermic. The enhanced Cd(II) uptake was primarily attributed to the synergistic effect of MnO x and oxygen-containing functional groups, which facilitated the formation of surface complexes. In conclusion, KMnO 4 modification represents an effective strategy for developing high-performance adsorbents for Cd(II) removal.
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高影响因子
危险品化学品经营许可证（带存储）