CHEMICAL ENGINEERING JOURNAL
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2018
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IF 6.735
Wei Teng,Nan Bai,Zehan Chen,Junming Shi,Jianwei Fan,Wei-xian Zhang
Porous carbon is the most important and most common adsorbent for the separation and treatment of organic pollutants. Characteristics such as accessible and large surface area, physical and chemical stability, and low-cost manufacturing method are desired for any adsorbent. Herein, a hierarchically porous carbon (HPC) was prepared by pyrolysis and graphitization of crystalline metal–organic frameworks (MOF-5) for enhanced adsorption of aromatic contaminants. The material treated at high temperature (950 °C) possesses large surface area (1512 m 2 /g), high porosity (0.94 cm 3 /g), and hierarchically porous structures. The generated mesopores around 4 nm improve the interconnectivity of micro- and macropores to make the porous material ideal for sorption of organic pollutants such as aromatic hydrocarbons. Effects of adsorbent dose, pH, ionic strength, contact time, and initial concentration on the adsorption of p -nitrophenol (PNP, as a model) were investigated. Adsorption isotherms and kinetics suggest that the adsorption is a spontaneous and endothermic physisorption process with monolayer surface coverage. The surface sites are electron-rich due to the graphitic layer, which has high affinity toward π electrons of the aromatic ring. The adsorption capacity of the hierarchically porous carbon (HPC) is nearly over 100% higher that of conventional activated carbon.
研究领域:
环境科学
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材料科学
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物理化学
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吸附分离
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污染治理
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2019
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IF 4.784
Linjun Wu,Siqi Huang,Jia Zheng,Zhongjie Qiu,Xuliang Lin,Yanlin Qin
The traditional polyvinyl alcohol composite hydrogel exhibited poor swelling and mechanical properties, which limited its application. To solve these issues, we use biomass lignin as raw material, PVA as matrix template and epichlorohydrin as cross-linker to prepare the Lignin-PVA super-absorbent hydrogels with the swelling ratio of up to 456 g/g under mild condition. When the lignin concentration was increased from vacancy to 5%, the swelling ratio of the Lignin-PVA hydrogels was increased from 92 g/g to 456 g/g. The lignin-based hydrogel synthesized by the higher molecular weight PVA showed better swelling performance. Softwood lignin, hardwood lignin and corncob lignin could also be used to fabricate the Lignin-PVA super-absorbent hydrogels with the swelling ratio of higher than 500 g/g. However, the optimum amount varied from different lignin types, which was related to the molecular weight and phenolic hydroxyl content of lignin. The structural mechanism of the Lignin-PVA hydrogel was proposed to clearly certify the enhancing role of lignin. The adsorption capacity of the Lignin-PVA hydrogel with respect to rhodamine 6G, crystal violet and methylene blue dyes was up to 196, 169 and 179 mg/g, respectively. The Lignin-PVA hydrogel presents great potential applications in the fields of soil water retention and seed cultivation in agriculture, and dye pollutant removal.
研究领域:
高分子材料
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环境科学
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农业工程
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功能材料
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污染治理
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2019
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IF 6.361
Qing Cen,Qiaoyuan Gao,Chenlu Zhang,Yingqi Liu,Qi Wang,Qi Wang
In this study, visible-light-active iron tungstosilicate (FeSiW) was fabricated via solvothermal method . Fe 3+ was applied as counter ion to precipitate with silicotungstic acid (H 4 SiW 12 O 40 ) in methanol solution. It can be observed from FT-IR spectra that the Keggin structure of SiW 12 O 40 4− was well maintained in FeSiW. Besides, the effect of different initial molar ratios of Fe 3+ to H 4 SiW 12 O 40 was investigated (from 4:1 to 4:4). By photoelectrochemical characterizations, such as photocurrent response and Mott-Schottky (M-S) plots, easiest generation of electron-hole pairs and lowest charge transfer resistance can be observed on FeSiW with initial molar ratio of 4:3. Moreover, FeSiW with 4:3 ratio also displayed highest activity for photocatalytic reduction of Cr(VI), despite of the largest band gap (ca. 2.71 eV). The lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) of the optimized FeSiW were estimated to be +0.03 V and 2.74 V vs NHE, respectively, which were thermodynamically feasible for Cr(VI) reduction and H 2 O oxidation . Even under acidic condition (pH 3), the optimized photocatalyst displayed good stability in cyclic runs. Therefore, the present study opens a new way for heterogeneous polyoxometalates as efficient photocatalyst for environmental application.
研究领域:
环境化学
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材料科学
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光催化
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无机化学
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污染治理
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
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2019
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IF 2.291
Zhuo Dai Li,Huai Qiang Zhang,Xiao Hong Xiong,Feng Luo
Covalent organic frameworks (COFs) represent an exciting new type of porous organic materials, which are constructed with organic building units via strong covalent bonds . Here in, the COF-2,4,6-Triformylphloroglucinol p-Phenylenediamine (COF-TpPa-1) was synthesized by solvothermal method for the removal of U(VI) from aqueous solution. Effects of pH, adsorption dose, contact time, uranium solution concentration, temperature and adsorption and desorption cycle on the efficiency of COF-TpPa-1 removal of U(VI) are investigated. SEM, XRD , TGA and FT-IR were employed to characterize the samples and analyze adsorption mechanism. The results manifested COF-TpPa-1 has the high adsorption capacity ( q m = 152 mg/g), quick adsorption kinetic , high selectivity , outstanding recycle performance and good resistance to acids, bases and high temperature.
研究领域:
环境化学
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材料科学
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核化学
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污染治理
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吸附科学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2017
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IF 3.671
Chan Li,Xuejing Wang,Duye Meng,Li Zhou
Magnetic biosorbents derived from renewable resource are emerging as a new class of adsorbing material for environmental cleanup because of their eco-friendly characteristic, easy availability and low cost. Herein, a novel magnetic peach gum bead (MPGB) biosorbent was successfully fabricated by a simple one-step reaction based on the simultaneous formation of magnetic nanoparticles and cross-linking of natural peach gum polysaccharide. Benefiting from the combined merits of peach gum and magnetic nanoparticles, the MPGB not only showed excellent adsorption performance for cationic dyes but also exhibited convenient magnetic separation capability. The influences of pH, ionic strength, initial dye concentration, contact time and temperature on the adsorption property of MPGB biosorbent were investigated by choosing methylene blue (MB) as a representative cationic dye. The Langmuir isotherm fitted the adsorption isotherm well with maximum adsorption capacity of 231.5 mg g −1 . Kinetic data showed good correlation with pseudo-second-order model. Thermodynamic investigation revealed that the adsorption process was spontaneous and endothermic. Moreover, the MPGB exhibits nice reusability. Considering the facile fabrication process and excellent adsorption performance, the MPGBs hold great promise for using as biosorbent for environmental cleanup.
研究领域:
环境科学
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材料科学
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高分子化学
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污染治理
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吸附技术
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绿色化学
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功能材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）