BIORESOURCE TECHNOLOGY
·
2019
·
IF 6.669
Jianhong Ma,Tong Li,Yutang Liu,Tao Cai,Yuanfeng Wei,Wanyue Dong,Hui Chen
In this study, lignin extracted from rice husk was used to synthesis double network hydrogel adsorbent, named RH-CTS/PAM gel. RH-CTS/PAM gel exhibited macroporous structure and high buried water content, which gave rise to the exceptional adsorption performance. As results, in individual systems, the equilibrium time of Pb(II), Cu(II) and Cd(II) with initial concentration of 200 mg/L could be reached within 10 min, with the theoretical maximum adsorption capacity of 374.32, 196.68 and 268.98 mg/g, respectively. The adsorption rate and capacity of Pb(II), Cu(II) and Cd(II) in multicomponent systems were lower than that of individual systems. However, in a few cases of ternary system, higher adsorption rate and capacity was observed compare to binary systems. Adsorption mechanism indicated that both oxygen-containing and nitrogen-containing functional groups played a dominant role during the adsorption process, and mainly through chemical interaction along with a small amount of physical interaction.
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
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Lingli Deng,Yang Li,Aiping Zhang,Hui Zhang
In this study, the gelatin/zein nanofibrous membranes with incorporation of nano-hydroxyapatite (nHA) were fabricated via electrospinning. The gelatin/zein/nHA solutions as the spinning dispersions showed the viscoelastic property with a shear-thinning non-Newtown behavior. The incorporated nHA particles in the composite nanofibrous membranes did not affect the average fiber diameter significantly, but induced agglomeration and nodules at higher contents. It was found that nHA was dispersed within the gelatin/zein nanofibers by the formed hydrogen bonding, resulting in a more extensional structure of the proteins. The addition of nHA significantly increased the hydrophobicity of the nanofibrous membranes, due to the lower ratio of polar groups exposed outside. However, the incorporation of nHA improved the mechanical property at a low content of 10%, but resulted in a more brittle and fragile property at higher contents. The copper adsorption capacity of the gelatin/zein nanofibrous membrane increased from 27.2 to 67.8 mg/g after the addition of up to 50% nHA. This work suggests the potentials of the electrospun gelatin/zein/nHA nanofibrous membranes as desirable materials for metal removal applications.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2016
·
IF 2.567
Kexin Zhang,Haiyan Li,Xingjian Xu,Hongwen Yu
In this work, we report a room-temperature approach to synthesizing nitrogen-functionalized graphene oxide (GO). The chemical structure of GO- triethylenetetramine-methacrylate (GO-TETA-MA) was characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and 13C nuclear magnetic resonance, respectively. The GO-TETA-MA demonstrated extremely efficient removal of copper from wastewater. The adsorption capacity was found to be 34.4 mg/g for Cu(II) (at pH = 5 and 25 °C). The final concentration of Cu(II) was lower than the quality standard for groundwater and even lower than the allowable level of copper contaminant in drinking water in China. The effects of several parameters on adsorption, including pH value, contact time, adsorption temperature, initial concentration, acid stability, and thermal stability, were investigated. Kinetic data were well-described by a pseudo-first-order model. Both Freundlich and Langmuir isotherm models were applied to the experimental data analysis, and the former proved to be a better fit. The underlying mechanism of synergistic adsorption of heavy metal ions was considered. Then, the removal efficiency for four copper fungicides was studied and was found to reach 100%. These results suggest that GO-TETA-MA has the potential to be applied in environmental management.
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
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Yaoyao Zhang,Kangze Yuan,Luca Magagnin,Xishe Wu,Zhenyi Jiang,Wei Wang
Schiff base silica aerogels (SCA-X) were synthesized using amino-containing organosilanes and salicylic aldehyde as functional monomers with ethyl orthosilicate hydrolysis condensation as carrier. The influence of SCA-X on the adsorption of Pb (II) and Cu (II) under different adsorption conditions was evaluated, including the effect of solution pH, isotherm, kinetics, thermodynamics and adsorption mechanism. The batch adsorption experiments showed that SCA2 had the optimum adsorption capacity for Pb (II) (357.1 mg/g) and Cu (II) (243.9 mg/g), leading to adsorption equilibrium within 120 min and 360 min, respectively. After six adsorption–desorption cycles, SCA2 still possessed satisfactory adsorption for Pb (II) and Cu (II), demonstrating the reusability of the SCA2 adsorbent material. Kinetic studies indicated that the adsorption process could be described by a pseudo-second-order kinetic model, adsorption isotherms were in accordance with the Langmuir model, indicative of monomolecular layer adsorption. Thermodynamics evaluation revealed the nature of the adsorption process was an endothermic spontaneous process. XPS analysis combined with DFT calculations confirmed that the interaction mechanism between SCA2 and Pb (II) occurred through the coordination between the nitrogen atom donor in the Schiff base and the oxygen atom donor in the benzene ring, while the interaction between SCA2 and Cu (II) occurred mainly through the coordination between the nitrogen atom in the Schiff base and Cu (II). Life Cycle Assessment (LCA) was introduced to analyze the environmental impact of the SCA2 fabrication process and eco-friendly approaches were provided, which eventually provided theoretical evidence for the application of as-prepared material in the handling of heavy metal effluents.
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 ENVIRONMENTAL MANAGEMENT
·
2021
·
IF 6.789
Yang Liu,Lixun Zhang,Zhengfang Zhang,Ying Zhang,Yuntao Guan
Silicon (Si) deficiency and heavy metals (HMs) pollution are common for farmland soil because of long-term intensive farming. In this study, a novel citrate-modified biochar (C-BC) was introduced as a soil conditioner to simultaneously increase the amount of plant-available Si (PASi) and immobilize HMs. The maximum amount of PASi released was 33.00 mg⋅g −1 from C-BC pre-treated with 0.1 mol⋅L −1 citrate (C-BC0.1). A formation–transport coupling mechanism for increasing the amount of PASi released was developed. Stable Si in the biomass was pyrolyzed to give silicate that was relatively mobile via nucleophilic attack of citrate and hydrolysis of amorphous Si. Silicate species were then released through the porous surface and widening cracks caused by pyrolysis . At citrate concentrations >0.1 mol⋅L −1 , the surface and cracks were easily blocked by precipitates formed during pyrolysis. The ability of C-BC to remove HMs was assessed using Cu as an example. C-BC0.1 was optimal for adsorbing Cu, and the maximum adsorption capacity was 271.73 mg⋅g −1 . The Cu adsorption mechanism mainly involved surface precipitation, surface complexation, electrostatic attraction and hydrogen bonding. Our research provides important implications for simultaneously addressing Si deficiency and HMs contaminant problems by these materials for soil amendment in agro-ecosystem.
研究领域:
农业生态学
·
环境科学
·
土壤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Yanjun Huang,Hailing Wu,Taikang Shao,Xia Zhao,Hong Peng,Yuefa Gong,Huihai Wan
A novel composite adsorbent of Ca-DTCS/ALG bead was prepared by immobilization of DTPA-modified chitosan micro-gels (DTCS) into the alginate matrix. The copper sorption properties of Ca-DTCS/ALG beads were tested and compared with the other two adsorbents of DTCS powder and plain alginate (ALG) beads. In addition, the mechanisms of copper sorption on the adsorbents were investigated by FTIR and XPS analysis. Similar to DTCS powder, Ca-DTCS/ALG beads exhibited high copper removal efficiency in strongly acidic solutions, whereas calcium, sodium and aluminum salts had little effect on its copper adsorption capacities. The maximum adsorption capacities of Ca-DTCS/ALG and DTCS were 107.5 and 106.0 mg g −1 at pH 3.0, respectively, which were close to the values predicted by the Sips model. However, the maximum adsorption capacity of ALG beads predicted by the Sips model was much higher than its experimental one (101.1 mg g −1 ). The copper adsorption equilibrium by DTCS powder was achieved within 1 min, nevertheless, ALG and Ca-DTCS/ALG gel beads reached the adsorption equilibrium within 500 min and 1440 min, respectively. Moreover, Ca-DTCS/ALG gel beads showed good reusability, but DTCS powder was not easily reused due to its notable swelling property. Furthermore, the efficiency of copper recovery by Ca-DTCS/ALG beads in the simulated electroplating wastewater at the copper concentration of 1–5 mg L −1 was much higher than that of DTCS and ALG beads. These results reveal that immobilization of DTCS into the alginate matrix greatly improves the adsorption and separation performance of the adsorbent.
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
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
·
2018
·
IF 1.795
Cai-xia WANG,Hui-ping HU,Xue-jing QIU,Ze-ying CHENG,Lu-jia MENG,Li ZHU
A novel silica-supported tert-butyl 2-picolyamino-N-acetate chelating resin (Si-AMPY-1) was successfully synthesized and characterized by elemental analysis, FT-IR, SEM and 13 C CP/MAS NMR. The adsorption behaviors of the Si-AMPY-1 resin for Cu(II) and Ni(II) were studied with batch and column methods. The batch experiments indicated that the Si-AMPY-1 resin adsorbed Ni(II) mainly via physisorption, while adsorbed Cu(II) via chemisorption. The column dynamic breakthrough curves revealed that the Si-AMPY-1 resin can efficiently separate Cu(II) from the simulated nickel electrolyte before the breakthrough point. Moreover, the concentration of Cu(II) in the column effluent was decreased to be less than 3 mg/L within the first 43 BV (bed volumes), and the mass ratio of Cu/Ni was 21:1 in the saturated resin, which completely satisfied the industrial requirements of the nickel electrorefining process. Therefore, it was concluded that the Si-AMPY-1 resin can be a promising candidate for the deep removal of Cu(II) from the nickel electrolyte.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）