ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2017
·Vol. 25
·期 4
·3922-3932
·
IF 2.741
Yi Xiaofeng,Yang Meixia,Mo Liuda,Xu Wenkai,Wang Shuai,He Jiarui,Gu Junjie,Ou Minrui,Xu Xiaoping
Copper in drinking water causes a significant environmental problem. Composite material based on alginate hydrogel has been gaining attention in the field of Cu(II) adsorption. However, alginate-based hydrogel exhibits poor mechanical property and relative low adsorption capacity which limit their application. The present study is devoted to the modification of chitosan/calcium alginate/Fe 3 O 4 (CAF) hydrogel microsphere by NaOH solution for enhancement of Cu(II) adsorption. Results reveal that modification of CAF via NaOH solution significantly improves the mechanical strength and Cu 2+ adsorption capacity of pristine materials. FTIR and XRD analysis confirms that CAF and newly prepared materials (NACAF) are successfully prepared. SEM and EDX are employed to analyze the surface morphology and elemental composition, respectively, both before and after their loading with Cu 2+ . XPS study demonstrates adsorption mechanism is based on chelation and ion-exchange. Compressive stress-strain curves demonstrate NACAF has better mechanical performance than CAF. The adsorption kinetics of the two adsorbents follow a pseudo-second-order model. The equilibrium data were best described by Langmuir isotherm model, and the estimated maximum equilibrium sorption capacity, q
m ,is 261.31 mg/g for the NACAF, which is larger than that of CAF (145.39 mg/g). Hence, NACAF shows excellent mechanical strength and high sorption capacity for Cu 2+ . It has great potential for Cu(II) removal in aqueous solutions.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Hang Yin,Qiuqiu Xiong,Miao Zhang,Bowen Wang,Fenge Zhang
In this study, magnetic composite microspheres (SCFP) were prepared by cross-linking chitosan (CS), sodium alginate (SA), poly(vinyl alcohol) (PVA), and ferric tetraoxide (Fe 3 O 4 ) in a CaCl 2 solution. CS and Fe 3 O 4 were encapsulated in gel spheres formed by cross-linking SA with Ca(II), while PVA facilitated the dispersion of CS in SA. SCFP was utilized as an adsorbent to remove Cu(II) from water. The effects of the initial pH of the solution, SCFP dosage, and initial Cu(II) concentration on the adsorption efficiency were investigated through batch experiments. The results demonstrated that the adsorption capacity reached 58.260 mg/g (removal rate = 97.1%) after 100 min of adsorption at a pH of 5. The removal rate remained above 90% even after 6 cycles of the cycling experiment. The incorporation of CS with other functional materials allowed SCFP to compensate for its inherent drawbacks such as low mechanical strength, poor acid resistance, and short service life. The pseudo-first-order kinetic model and Freundlich adsorption isotherm provided better descriptions of the adsorption process. A comprehensive analysis was conducted on the structure and adsorption mechanism of SCFP using characterization techniques such as SEM-EDS, FTIR , BET, XRD , etc. In summary, SCFP has the potential to be an excellent environmentally friendly material for the removal of Cu(II).
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2021
·Vol. 45
·期 40
·19032-19042
·
IF 3.591
Chengmin Hou,Hanxiao Ma,Congjun Cao,Xiaojian Ding,Jingting Duan
The composite particles (St/Fe3O4) of starch and Fe3O4 were prepared by a co-precipitation method. Then AA and HEMA were grafted and cross-linked on St/Fe3O4 by a one-step method to obtain St/Fe3O4-g-p(AA-r-HEMA). The effects of the adsorbent dosage, pH value, initial Cu(II) concentration, time and temperature on adsorption were studied. Experiments showed that St/Fe3O4-g-p(AA-r-HEMA) showed a good adsorption performance for Cu(II), with a unit adsorption capacity of 75.5 mg g−1 and a maximum removal rate of 95.0%. The adsorption process followed the Langmuir model and the pseudo-second-order kinetic model, was dominated by chemical adsorption, and belonged to single-layer adsorption. Renewable performance studies showed that after 8 adsorption cycles, 91.2% of the first adsorption effect was still retained.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2019
·
IF 3.25
Yuting Chu,Muhammad Asim Khan,Fengyun Wang,Mingzhu Xia,Wu Lei,Sidi Zhu
Arg-Mt, was fabricated by modifying sodium montmorillonite (Na-Mt) with Arginine monohydrochloride (Arg salt), to adsorb Pb(II) and Cu(II) in aqueous solution. The X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectrum, thermal analysis (TG/DTG), Brunauer-Emmett-Teller (BET) and Scanning electron microscope (SEM) were employed to investigate the properties of Na-Mt and Arg-Mt. The effects of the amount of modifier, pH value, the initial concentration of M(II), temperature and contact time were tested in a single adsorption system. The isotherm model was well matched with the Langmuir curve and the kinetic adsorption fitted well with the pseudo-second-order rate equation. The saturated adsorption of Pb(II) and Cu(II) by Arg-Mt were 124.69 and 29.15 mg/g, respectively, which were higher than that of Na-Mt (89.08 and 23.93 mg/g). The thermodynamic equation indicated that the adsorption process was spontaneous, endothermic, and the randomness of the samples changed a little after adsorption. The adsorption capacity of heavy metal ions in the binary co-adsorption system was poor than single adsorption system. Furthermore, the adsorbed M(II) onto Arg-Mt can hardly be dissolved under weak acidic condition (pH > 4) according to the desorption experiments. High-efficiency and low-cost make Arg-Mt to be used in the removal of heavy ions in aqueous solution.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2016
·
IF 4.836
Chunzhen Fan,Kan Li,Juexiu Li,Diwen Ying,Yalin Wang,Jinping Jia
In this paper, tetraethylenepentamine (TEPA) modified chitosan/CoFe 2 O 4 particles were prepared for comparative and competitive adsorption of Cu(II) and Pb(II) in single and bi-component aqueous solutions. The characteristics results of SEM, FTIR and XRD indicated that the adsorbent was successfully fabricated. The magnetic property results manifested that the particles with saturation magnetization value of 63.83 emu g −1 would have a fast magnetic response. The effects of experimental parameters including contact time, pH value, initial metal ions concentration and coexisting ions on single and bi-component adsorption were investigated. The results revealed that the adsorption kinetic was followed pseudo-second-order kinetic model, indicating that chemical adsorption was the rate-limiting step. Sorption isotherms were also determined in single and bi-component solutions with different mass ratio of Cu(II) to Pb(II) (Cu(II)/Pb(II)) and fitted using Langmuir and Freundlich isotherm models. A better fit for Cu(II) and Pb(II) adsorption were obtained with Langmuir model, with a maximum sorption capacity of 168.067 and 228.311 mg g −1 for Cu(II) and Pb(II) in single component solution, 139.860 and 160.256 mg g −1 in bi-component solution (Cu(II)/Pb(II) = 1:1), respectively. The present results suggest that TEPA modified chitosan/CoFe 2 O 4 particles are feasible and satisfactory adsorbent for efficient removal of Cu(II) and Pb(II) ions.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2015
·
IF 2.858
Zhan-Chao Wu,Zhao-Zhan Wang,Jie Liu,Jin-Hua Yin,Shao-Ping Kuang
A new porous magnetic chitosan modified by melamine (MA-CS/Fe 3 O 4 ) was synthesized. The compositions and surface topographies were characterized by infrared (IR) spectroscopy, X-ray diffraction (XRD) analysis, thermogravimetric (TG) analysis and scanning electron microscope (SEM), respectively. The results of adsorption kinetics showed the adsorption behavior could be better described by the pseudo-second-order equation ( R > 0.999). The adsorption isotherm was well fitted by the Langmuir equation ( R > 0.999), and the values of separation factors were in the range of 0–1.0. The maximum adsorption capacity for Cu(II) was 2.58 mmol g −1 at the optimal experimental conditions, which were pH = 5.5, t = 25 min, C 0 = 5.0 mmol L −1 . The rate-controlling step was supposed to be chemical adsorption rather than mass transport. The adsorbent still exhibited high adsorption capacity after five regeneration cycles. The adsorption mechanism was due to coordination between Cu(II) and N atoms.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2019
·
IF 3.834
Zhixing Xiao,Lijuan Zhang,Long Wu,Dan Chen
In this study, a novel adsorbent was synthesized through the entrapment of KMnO 4 modified biochar (MB) in poly(vinyl alcohol)/sodium alginate hydrogel bead (PSMB) and then tested to determine its capacity for removal of Cu(II) from aqueous solutions. The maximum Cu(II) adsorption capacity estimated with Langmuir isotherm modeling was 87.07 mg/g of PSMB, which was higher than that of previously reported adsorbents. PSMB had a good selectivity towards Cu(II) as well as high anti-interference ability. The main species for Cu(II) adsorption likely were the inner-sphere Cu-O complexes, as indicated by the results of spectral analyses. The PSMB was easily collected and exhibited a minimal loss of adsorption capacity after 10 adsorption/regeneration cycles. The effective removal of Cu(II) from environmental water samples with relative low treatment cost indicated a possibility for practical application.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POROUS MATERIALS
·
2020
·Vol. 28
·期 1
·299-310
·
IF 2.183
Ma Zixuan,Li Fang,Jia Aizhong,Zhang Xiao,Wang Yanji
The highly efficient adsorbents with fast adsorption rate, high adsorption capacity and selectivity as well as good reusability were successfully synthesized through fabricating 3D spherical-chain porous silica material and grafting modification with ethylenediaminetetraacetic acid (EDTA) for the selective removal Cu(II) from wastewater. The obtained adsorbents were characterized by XRD, FT-IR, SEM, TEM, XPS, N 2 adsorption–desorption and back titration. The results indicate that the 3D framework structure is adjustable in a certain range by varying the parameters of the synthesis system. And the adsorption performance of the materials was investigated under different conditions such as pH, contact time and initial metal ions concentration. Under the experiment conditions, the synthesized adsorbent is efficient in removing Cu(II) and the adsorption equilibrium could be achieved within only 5 min, and the kinetic data are well fitted by pseudo-second-order and Langmuir isotherm models. The prepared adsorbents display good selective adsorption of Cu(II) and can be feasibly regenerated without evident decrease even after five recycles. Basing on the obtained results, the plausible adsorption mechanism was proposed and analyzed.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Marine Science
·
2021
·
IF 4.912
Han Xiaoxin,Vogt Rolf D.,Zhou Jiaying,Zheng Boyang,Yu Xue,Feng Jianfeng,Lu Xueqiang
Environmental effects of microplastic are rather due to their adsorption capacity of contaminants than themselves. Aging is a key factor influencing adsorption properties of environmental microplastics. In order to clarify this influence, polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET) microplastics with particle sizes of <0.9 mm, 0.9–2 mm, and 2–5 mm were artificially aged in seawater for 12 months. This enabled an assessment of the change in Cu(II) adsorption capacity to the microplastics particles under aging. According to the FTIR spectra, fresh microplastics were oxidized during the UV induced aging process. The adsorption capacities of microplastic were positively correlated with their aging time. After 12-months aging, the amount of Cu(II) adsorbed to the aged microplastics was 1.45–2.92 times higher than on the fresh microplastic particles. For PP and PET, the aging effect increased with decreasing size of the microplastic particles. In the case of PE, particles with the medium particle size (0.9–2 mm) had the strongest aging effect.
研究领域:
环境科学
·
材料科学
·
海洋科学
✓ 已验证
DOI
高影响因子
POLYMER BULLETIN
·
2021
·Vol. 79
·期 2
·1201-1216
·
IF 2.87
Yu Changjiang,Li Han,Ma Haoyue,Zhang Limei,Li Yu,Lin Qiang
A magnetic composite microsphere, calcium alginate (CA)/carboxymethyl cellulose (CMC)@MnFe 2 O 4, was prepared using CA and CMC encapsulated MnFe 2 O 4 through blending and cross-linking for the removal of Cu(II) from aqueous solution. The CA/CMC@MnFe 2 O 4 was characterized in detail by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and X-ray phosphorescence spectroscopy. In addition, various adsorption conditions including the initial pH of Cu(II) solution, equilibrium contact time, and initial Cu(II) concentration were tested. The adsorption data fit better to the Langmuir isotherm and follow the pseudo-second-order model, suggesting that it is a monolayer adsorption process with chemisorption as the rate-limiting step. The maximum adsorption capacity of the CA/CMC@MnFe 2 O 4 was 77.22 mg g −1 at 25 ℃ and pH 5. Cu(II) removal mechanisms of CA/CMC@MnFe 2 O 4 follow ion exchange as well as the formation of complexes as evidenced based on the microstructure analysis and adsorption data fitting.
研究领域:
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
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Tianguang Wang,Jinsong Zeng,Pengfei Li,Fugang Hu
Hydrogels can effectively address various adsorption requirements as a multifunctional adsorbent material with a three-dimensional spatial network. However, conventional hydrogels, typically synthesized using the one-pot method, often exhibit a heterogeneous internal structural arrangement, leading to non-uniform stress distribution when interacting with heavy metal ions. This has resulted in the structural disruption of conventional hydrogels in the adsorption of heavy metal ions, and they exhibit low adsorption performance, low cycling performance, and non-selective adsorption. Herein, a preassembled framework structure hydrogel (Cu 2+ -CNF hydrogel) was developed by introducing template ions (Cu 2+ ), which have been coordinated with monomers (Acrylic acid and Acrylamide), into a network of cellulose nanofibrils (CNFs) polymers. The obtained Cu 2+ -CNF hydrogel exhibited excellent adsorption properties(Cu 2+ -CNF hydrogel, 402 mg/g) compared to those prepared by the one-pot method(CNF hydrogel, 129 mg/g). In addition, the Cu 2+ -CNF hydrogel has superior selective adsorption property and tensile strain properties (CNF hydrogel: 20 % to Cu 2+ -CNF hydrogel: 100 %) at higher swelling ratios (CNF hydrogel: 2313 wt% to Cu 2+ -CNF hydrogel: 8379 wt%). Even after multiple folding or repeated adsorption–desorption cycles, the integrity of the structure and adsorption function can still be maintained. This work provides a general strategy for preparing a new type of nanocellulose hydrogel.
研究领域:
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）