SCIENCE OF THE TOTAL ENVIRONMENT
·
2023
·
IF 9.8
Peng Yi,Yani Yan,Ying Kong,Quan Chen,Min Wu,Ni Liang,Lijuan Zhang,Bo Pan
Wetting-drying cycles in the environment could change the inner- or outer-sphere complexation of heavy metal cations on natural organic matter (NOM) and then influence ternary interactions with organic contaminants - a rarely-discussed essential geochemical process. In this work, the sorption of sulfamethoxazole (SMX) on humic acids (HAs) mediated by cations (Cu 2+ and Cd 2+ ) was investigated. Considering that outer-sphere complexation could be transformed into inner-sphere complexation during vacuum freeze-drying, the role of inner- or outer-sphere complexation on SMX sorption was explored. The experimental sorption results and density functional theory (DFT) calculations suggested that Cu 2+ and Cd 2+ sorption on HAs was mainly outer- and inner-sphere complexation, respectively. Cd 2+ consistently promoted SMX sorption on HAs, while Cu 2+ promoted and inhibited SMX sorption before and after freeze-drying. The structure of HA-Cu complexes with inner-sphere complexation was more compact than those with outer-sphere complexation, which reduced the accessibility of sorption sites for SMX on HA-Cu and inhibited SMX sorption. However, the greater number of coordination sites of Cd 2+ may provide more sorption sites and the structure of HA-Cd was looser. These findings provide a groundbreaking understanding of the sorption of organics on natural adsorbents in the presence of cations.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2023
·Vol. 15
·期 11
·2416
·
IF 5
Siqing Ye,Weiye Zhang,Xingliang Hu,Hongxing He,Yi Zhang,Weili Li,Guangyuan Hu,Yue Li,Xiujun Deng
A novel recoverable magnetic Cd(II) ion-imprinted polymer was synthesized on the surface of silica-coated Fe3O4particles via the surface imprinting technique and chemical grafting method. The resulting polymer was used as a highly efficient adsorbent for the removal of Cd(II) ions from aqueous solutions. The adsorption experiments revealed that Fe3O4@SiO2@IIP had a maximum adsorption capacity of up to 29.82 mg·g−1for Cd(II) at an optimal pH of 6, with the adsorption equilibrium achieved within 20 min. The adsorption process followed the pseudo-second-order kinetic model and the Langmuir isotherm adsorption model. Thermodynamic studies showed that the adsorption of Cd(II) on the imprinted polymer was spontaneous and entropy-increasing. Furthermore, the Fe3O4@SiO2@IIP could rapidly achieve solid–liquid separation in the presence of an external magnetic field. More importantly, despite the poor affinity of the functional groups constructed on the polymer surface for Cd(II), we improved the specific selectivity of the imprinted adsorbent for Cd(II) through surface imprinting technology. The selective adsorption mechanism was verified by XPS and DFT theoretical calculations.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL RESEARCH
·
2023
·
IF 8.3
Xiaoyu Zheng,Qiuju Wu,Chao Huang,Ping Wang,Hao Cheng,Chengyou Sun,Jian Zhu,Haiyin Xu,Ke Ouyang,Jing Guo,Zhiming Liu
Biochar derived from bamboo was used to support sulfide nanoscale zero-valent iron (S-nZVI@BC) for simultaneous removal of Cd(II) and As (III) from aqueous media. Scanning electron microscopy (SEM) and X-ray diffraction spectroscopy (XRD) characterization confirmed the successful synthesis of the S-nZVI@BC. Adsorption kinetics and isotherms indicated that co-adsorption of Cd(II) and As(III) onto S-nZVI@BC was well represented by pseudo-second-order model ( R 2 Cd(II) = 0.990, R 2 As(III) = 0.995) and Langmuir model ( R 2 Cd(II) = 0.954, R 2 As(III) = 0.936). The maximum adsorption was 162.365 and 276.133 mg/g for Cd(II) and As(III), respectively, in a co-adsorption system, which was significantly higher than that in a single adsorption system (103.195 and 223.736 mg/g, respectively). Batch experiments showed that the Cd(II)-to-As(III) concentration ratio significantly affected the co-adsorption with the optimal ratio of 1:2. Ca 2+ and Mg 2+ significantly inhibited Cd(II) removal. In contrast, phosphate and humic acid significantly inhibited As(III) removal. Electrochemical analysis indicated S-nZVI@BC had a lower corrosion potential and resistance than nZVI@BC, making it more conducive to electron transfer and chemical reaction. Electrostatic adsorption, complexation, co-precipitation, and redox were the primary mechanisms for Cd(II) and As(III) removal. Overall, the present study provides new insights into the synergistic removal of Cd(II) and As(III) by S-nZVI@BC, which is a very promising adsorbent for the effective removal of Cd(II) and As(III) from contaminated wastewater.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
·
2023
·
IF 3.8
Hai Liang,Xinyu Feng,Xiuyuan Zuo,Zhihan Zhu,Siman Yang,Baowei Zhu,Wanting Wang,Jingjing Zhang,Gang Li
MgO-modified biochar (MgO-BC) has demonstrated enormous potential for practical application of Cd(Ⅱ) removal from wastewater. Exceptionally numerous MgO adsorption sites and enhanced porosity of MgO-BC are both critical for efficiency Cd(Ⅱ) removal. However, the pursuit of high-content of MgO while maintaining unobstructed pore structure remains a challenge due to the blockage of BC pores by the MgO particles. Herein, we demonstrated that Mg(NO 3 ) 2 can synergistically enhance the porosity and MgO active site of biochar attributing to the oxidation of nitrate. The prepared MgO-BC exhibits highly porous framework structure. Remarkably, further adsorption results indicate the MgO-BC has outstanding adsorption capacity of Cd(Ⅱ) in solution. The immobilized contaminant Cd(Ⅱ) onto MgO-BC was predominantly attributable to the chemical and physical interaction, including ion exchange, cation-π interaction, surface complexation and electrostatic interaction. This strategy demonstrates a novel route to develop efficient adsorbents by tailoring structure and metal oxide via nitrate activation.
✓ 已验证
产品关联
DOI
高影响因子
npj Science of Food
·
2023
·Vol. 7
·期 1
·1-10
·
IF 6.4
Qiu Chao,Zhang Zhiheng,Li Xiaojing,Sang Shangyuan,McClements David Julian,Chen Long,Long Jie,Jiao Aiquan,Xu Xueming,Jin Zhengyu
In this study, composite nanoparticles consisting of zein and hydroxypropyl beta-cyclodextrin were prepared using a combined antisolvent co-precipitation/electrostatic interaction method. The effects of calcium ion concentration on the stability of the composite nanoparticles containing both curcumin and quercetin were investigated. Moreover, the stability and bioactivity of the quercetin and curcumin were characterized before and after encapsulation. Fluorescence spectroscopy, Fourier Transform infrared spectroscopy, and X-ray diffraction analyses indicated that electrostatic interactions, hydrogen bonding, and hydrophobic interactions were the main driving forces for the formation of the composite nanoparticles. The addition of calcium ions promoted crosslinking of the proteins and affected the stability of the protein–cyclodextrin composite particles through electrostatic screening and binding effects. The addition of calcium ions to the composite particles improved the encapsulation efficiency, antioxidant activity, and stability of the curcumin and quercetin. However, there was an optimum calcium ion concentration (2.0 mM) that provided the best encapsulation and protective effects on the nutraceuticals. The calcium crosslinked composite particles were shown to maintain good stability under different pH and simulated gastrointestinal digestion conditions. These results suggest that zein–cyclodextrin composite nanoparticles may be useful plant-based colloidal delivery systems for hydrophobic bio-active agents.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Lingmin Sun,Junshu Wu,Jinshu Wang,Meng Xu,Wenyuan Zhou,Yucheng Du,Yongli Li,Hongyi Li
With rising global concerns about the discharge of large volumes of waste materials derived from industrial manufacture and human life, methods for utilizing waste materials have been greatly developed. In this study, an ingenious hydroxyapatite (Hap) functionalized hierarchical porous biochar (HB) composite is fabricated using a filtrate rich in Ca 2+ ions after steel slag reuse and spent Hami melon peel as raw materials. Microstructural analyses indicate that Hap nanoparticles are loaded on HB with hierarchical pores produced from a pyrolysis process of Hami melon peel. A series of HB-Hap materials by tuning HB addition amount (0.5, 1, and 2 g) can be obtained through a coprecipitation process. As a case study, HB-0.5Hap exhibits high specific surface area of 66.92 m 2 /g and high-efficiency removal performance for Pb(II) and Cd(II) ions in wastewater. The maximum adsorption capacities of HB-0.5Hap are 134.4 (Pb(II)) and 60.4 (Cd(II)) mg/g, which are 1.77 and 1.23 times higher than that of pure HB, respectively. It is attributed to a synergistic mechanism involving ion exchange, chemical precipitation , surface complexation, and cation-π interaction. According to a semi-quantitative calculation, ion exchange plays a major role in the removal of Pb(II) (78.61%, the relative contribution of ion exchange mechanism) and Cd(II) (77.77%). This study demonstrates a facile, economical, and sustainable strategy for the value-added utilization of steel slag and spent Hami melon peel, which can be critical in solving environmental problems.
✓ 已验证
产品关联
DOI
高影响因子
WATER AIR AND SOIL POLLUTION
·
2023
·Vol. 234
·期 3
·1-12
·
IF 2.9
Liu Caiying,Liu Yanyan,Feng Jiapeng,Li Yaru,Tao Jun,Xie Xiaoxiao
The paper aims to evaluate the effectiveness of biochar prepared from the co-pyrolysis of rice husk and cow bone (RHCBC) for in situ remediation and amelioration of Cd-contaminated soil. Effects of RHCBC on Cd bioavailability in soil and Cd uptake in corn growth were investigated through cultivation experiments and pot experiments. The results showed that the addition of RHCBC in the Cd-contaminated soil achieved the increase of soil pH, CEC, and SOM, whereas the soil available Cd content was reduced by 29.08–51.06%, which was proved by the transformation of Cd from acid soluble and exchangeable state to residual state. Furthermore, the nutrient contents of soil were also increased by 82.41–230.09% for alkali-hydrolyzable N, 66.81–144.03% for available P, and 16.20–77.70% for available K, respectively, which promoted the growth of corn. Overall, it is a promising strategy to employ RHCBC for in situ remediation of Cd-contaminated soil and promotion of plant growth as efficient soil amendment.
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 41
·23474-23483
·
IF 3.049
Chunsheng Xie,Shoulian Wei,Dan Chen,Wenying Lan,Zijun Yan,Zhenxing Wang
In this work, a magnetic ion imprinted polymer (MIIP) with specific recognition capability toward cadmium was prepared by a sol–gel method using waste beer yeast, which is a macromolecule biomass, as a functional monomer. The obtained Cd(II)-MIIP was characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and adsorption experiments. Then, a MIIP adsorbent based magnetic solid phase extraction (MSPE)-graphite furnace atomic absorption (GFAA) method was established to analyze the cadmium content in food and environmental samples. The maximum cadmium adsorption capacities by the MIIP and magnetic non-imprinted polymer (MNIP) were 62.74 and 32.38 mg g−1, respectively. The absorption by the MIIP was fitted using a pseudo-second-order kinetic model. The Cd(II)-MIIP demonstrated superior absorption capability for selective removal cadmium. The recovery rate of the MIIP was 90.7% after four adsorption–desorption cycles. The calculated Cd(II) detection limit (S/N = 3) was 0.18 μg L−1 with the relative standard deviation (RSD) equal to ∼3.5% for 10 μg L−1 of Cd(II) standard solution. Our proposed method was successfully used in detecting Cd(II) in aqueous samples. The results obtained in this work suggest that the Cd(II)-MIIPs might be promising adsorbents to remove harmful cadmium ions from aqueous samples.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2019
·
IF 4.865
Meiqing Chen,Pingxiao Wu,Zhiyan Huang,Junqin Liu,Yihao Li,Nengwu Zhu,Zhi Dang,Yinzhi Bi
The MgMn-layered double oxide (MgMn-LDO), which was fabricated by calcining MgMn-layered double hydroxide (MgMn-LDH), was used to remove tetracycline (TC) and cadmium (Cd) pollution. In MgMn-LDO activated peroxymonosulfate (PMS) system, 97.1% of TC was degraded within 20 min. The high oxidizing sites exposed on MgMn-LDO surface played a main role on activating PMS to generate OH, SO 4 − , O 2 − and 1 O 2 (the key species) for TC degradation . MgMn-LDO could keep excellent degradation performance in a wide range of pH (from 4 to 10). The degradation degree of TC in distilled water is basically the same as that in Pearl River water, and even above 80% of TC could be degraded in human urine. The good reusability and high structure stability of MgMn-LDO were further verified. Meanwhile, Cd immobilization on MgMn-LDO reached equilibrium within 10 min, and its maximum fixed quantity was 8.234 mmol g −1 (922.208 mg g −1 ). The outstanding Cd fixed ability resulted from the formation of CdCO 3 and Cd (OH) 2 . In combined system, the existence of TC promoted the immobilization of Cd on MgMn-LDO. Low concentration of Cd (0.0125 mM) had synergism effect on TC degradation, while high concentration of Cd (0.025 and 0.05 mM) had inhibiting action. Finally, a column filled with MgMn-LDO was designed for repairing TC and Cd pollution hierarchically. This study provided an effective strategy to clean up the organic-heavy metal combined pollution.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2016
·
IF 3.976
Y.H. Zhao,X. Jia,W.K. Wang,T. Liu,S.P. Huang,M.Y. Yang
Plant secondary metabolites play a pivotal role in growth regulation, antioxidant activity, pigment development, and other processes. As the global climate changes, increasing atmospheric temperatures and contamination of soil by heavy metals co-occur in natural ecosystems, which alters the pH of rhizosphere soil and influences the bioavailability and mobility of metals. Elevated temperatures in combination with heavy metals are expected to affect plant secondary metabolites, but this issue has not been extensively examined. Here, we investigated secondary metabolites in Robinia pseudoacacia seedlings exposed to elevated temperatures using a passive warming device in combination with Cd- and Pb-contaminated soils. Heavy metals significantly stimulated the accumulation of saponins, phenolic compounds , and flavonoids in leaves and stems; alkaloid compounds increased in leaves and decreased in stems, and condensed tannins fluctuated. Elevated temperatures, alone and in combination with Cd and Pb, caused increases in secondary metabolites in the plant tissues. Phenolic compounds showed the greatest changes among the secondary metabolites and significant interactive effects of temperature and metals were observed. These results suggest that slightly elevated temperature could enhance protective and defense mechanisms of Robinia pseudoacacia seedlings exposed to heavy metals by stimulating the production of secondary metabolites.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2016
·
IF 4.836
Sheng Deng,Peng Wang,Guangshan Zhang,Yuan Dou
A novel thiosemicarbazide modified adsorbent (PAN MW –TSC) based on polyacrylonitrile fiber was successfully synthesized under microwave irradiation, which was applied for the uptake of Cd(II) and Pb(II) from aqueous solution subsequently. Microwave irradiation method is a new approach to achieve the modification and it turns out that just a 30 min process is enough for the anchoring of functional groups in the fiber matrix. The surface characterization was performed by fourier transform infrared spectroscopy (FT–IR), scanning electron microscopy (SEM) elemental analysis (EA) and thermogravimetric analysis (TGA), indicating that the modification was successfully accomplished. Batch adsorption experiments including equilibrium isotherms, kinetics and the effects of pH and temperature on the adsorption of Cd(II) and Pb(II) were systematically studied. Among three kinetic models, the pseudo-second-order kinetic model provides the best correlation for the process. The nonlinear resolution of the Langmuir isotherm equation has been found to show the closest fit to the equilibrium date. Thermodynamic parameters, involving △ G , △ H and △ S were also calculated from graphical interpretation of the experimental data, which suggest that metal ions adsorption onto PAN MW –TSC fibers is spontaneous and exothermic. Regeneration of PAN MW –TSC fibers loaded with metal ions was efficiently done with 0.5 M HNO 3 , by which the investigated adsorbent could be used reproductively for five times with a small decrease in sorption capacity. The feasible preparation of PAN MW –TSC fibers with high adsorption capacities opens a new perspective in the potential application for wastewater treatment .
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SURFACE AND INTERFACE ANALYSIS
·
2014
·Vol. 47
·期 2
·270-277
·
IF 1.393
Yongli Shi,Suying Ma,Ruiqiong Tian,Yingge Zhao,Qian Jiao,Xu Ma,Qing Shang
A novel amphiphilic copolymer was synthesized from poly (ethylene glycol) methyl ether methacrylate (PEGMA950), methyl methacrylate (MMA) and acryloyl- β -cyclodextrin (acryloyl- β -CD) using the composites of (NH 4 ) 2 S 2 O 8 /NaHSO 3 as the oxidation–reduction initiators. The successful fabrication of poly(PEGMA-co-MMA-co-acryloyl- β -CD) copolymers was confirmed by Fourier transform infrared spectrometer (FTIR), 1 H-nuclear magnetic resonance ( 1 H NMR) spectra. The amphiphilic copolymer could self-assemble into nanoparticles (NPs), and their morphology and particle size distribution were characterized with transmission electron microscopy (TEM), atomic force microscope (AFM) and dynamic light scattering (DLS) methods. Ibuprofen (IBU) was encapsulated in the novel NPs, and the release profiles of IBU were investigated. FTIR and 1 H NMR spectra illustrated that the poly(PEGMA-co-MMA-co-acryloyl- β -CD) copolymers were synthesized without any residual monomers and initiators. TEM and AFM photographs suggested that the obtained NPs were spherical, and the DLS results indicated that the diameter of blank NPs was 157.3 ± 32.7 nm. The IBU release profile showed that the IBU-loaded NPs had certain pH responsibility. Copyright © 2014 John Wiley & Sons, Ltd.
✓ 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）