FIBERS AND POLYMERS
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2015
·Vol. 16
·期 10
·2130-2134
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IF 0.881
Chen Yingbo,Wang Biao,Zhang Shifeng,Hu Xiaoyu,Cheng Bowen,Liu Dongqing,Zhang Yufeng
Cu-BTC/PVDF composite membranes were prepared by immersing PVDF hollow fiber supporting membranes into copper acetate aqueous solution and trimesic acid ethanol solution repeatedly. Surface and cross sectional morphologies of Cu-BTC crystals on the supporting PVDF membrane were investigated using SEM. Chemical composition and crystal structure of Cu-BTC were characterized by IR and XRD. Gas permeance and separation factor for CO 2 and N 2 of the Cu- BTC/PVDF composite membrane were recorded under different pressures. The results illustrated that with increasing reaction times, the crystal layer became more in density and less in defects, resulting in decrease of gas permeance and the separation mechanism changing from convective flow to Knusen diffusion.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
DESALINATION
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2017
·
IF 5.527
Heiyan Zhang,Bingbing Li,De Sun,Xiaoling Miao,Yunlei Gu
In this study, hydrophobic asymmetric SiO 2 -PDMS-PVDF hollow fiber membranes were prepared for the vacuum membrane distillation (VMD). To make PVDF dope solution, hydrophobic nano-fumed silica (SiO 2 ) and polydimethylsiloxane (PDMS) were used. The effects of SiO 2 concentration on membrane parameters such as membrane morphology, hydrophobicity , porosity, thickness, pore size, liquid entry pressure , burst pressure, Fourier transformed infrared spectroscopy , thermal property, mechanical property and permeability were investigated. With the increasing of nano-particle concentration, membrane hydrophobicity, mechanical property and thermal stability improved. Furthermore, membrane VMD properties under various operation conditions were studied, the membranes showed a stable substantial flux of 44.27 LMH and a stable high salt rejection of over 99.9% under the optimum operation conditions of 75 °C, 35 g/L, 87 kPa, and 50 L/h. The results of our research demonstrated that the prepared hydrophobic asymmetric SiO 2 -PDMS-PVDF hollow fiber membranes not only had high permeability and good anti-wetting property but also exhibited a satisfying stability for the vacuum membrane distillation of desalination .
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
·
2023
·
IF 4.1
Qin Wang,Huizi Li,Xiaojie Liu,Tingyao Du,Jianyu Guo,Siyong Zhang,Yan Lu
In this work, a carbon-based monolith with macroporous-mesoporous structure derived from polyvinylidene fluoride (PVDF) hollow fiber membranes is reported. The Co 2+ soaked PVDF hollow fiber membranes are treated with vinyltrimethoxysilane (VTMS) and calcined at relatively low temperatures (600 °C) to obtain a carbon-based material with a distinctive honeycomb porous structure . The VTMS treatment is the committed step, which provides a hard SiO 2 protective layer for the PVDF hollow fiber membrane during the calcination process to support the skeleton structure and prevent the macrostructure collapse and also plays a role in expanding mesopores. The obtained hierarchically porous structure can improve the electrochemical activity of the carbon-based material. In a three-electrode system, the specific capacitance of 701.0 F g −1 can be achieved at a current density of 1 A g −1 , and the retention rate is 112.1 % after 10,000 cycles at 10 A g −1 . The assembled quasi-solid-state symmetric supercapacitor can be operated in a 0–1.4 V voltage window, and it demonstrates an energy density of 26.3 Wh kg −1 at the power density of 349.9 W kg −1 .
研究领域:
材料科学
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能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
Cleaner Engineering and Technology
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2021
·
IF 0
Huijuan Gong,Honglei Pang,Mengfan Du,Zezhi Chen
In order to obtain high performance polyvinylidene fluoride (PVDF) hollow fiber membrane for post combustion carbon dioxide (CO 2 ) capture from flue gas by membrane contact absorption technology, a novel mixed matrix membrane fabrication process was proposed in this study. The mixed matrix PVDF-SiO 2 (silicon dioxide)-HDTMS (hexadecyltrimethoxysilane) hollow fiber membranes fabricated via this process exhibit super-hydrophobicity on the outer surface and high mechanical strength. Among the membranes, the PVDF-SiO 2 (1.5)-HDTMS membrane exhibited the highest CO 2 absorption performance, which was due to its excellent properties. It had water and diethanolamine (DEA, 1 mol/L) contact angles of 159.3° and 157.5°, respectively. Tensile strength, elongation at break, and LEP W (liquid entry pressure of water) of it were 3.2 × 10 6 Pa, 35.0%, and 9.0 × 10 5 Pa, respectively. The CO 2 absorption flux of PVDF-SiO 2 (1.5)-HDTMS membrane attained 2.39 × 10 −3 mol‧m −2 ‧s −1 , which was 7.2% and 141.4% higher than that of the PVDF-HDTMS-1.5 and PVDF membranes, respectively. Moreover, CO 2 absorption flux of the PVDF-SiO 2 (1.5)-HDTMS membrane decreased only 3% after twenty days of continuous operation. Highlighted by the outstanding performance in membrane contact CO 2 absorption, the PVDF-SiO 2 (1.5)-HDTMS membrane shows great potential in the application of membrane contact absorption for post-combustion CO 2 capture.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
JOURNAL OF MEMBRANE SCIENCE
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2024
·
IF 8.4
Wei-Min Liu,Xin-Ru Chen,Heng Mao,Shen-Hui Li,Yan-Mei Zhang,Li-Hao Xu,Zhi-Ping Zhao
Construction of ultra-thin and defect-free separation membrane on inner surface of hollow fiber supports is significant but challenging for molecular separation. In this study, the highly permeable PDMS@ZIF-8/PVDF composite membranes were successfully fabricated upon the inner-surface of polyvinylidene fluoride (PVDF) hollow fiber membrane for pervaporation (PV) ethanol/water separation. The efficient preparation of hierarchical PDMS@ZIF-8/PVDF composite membranes benefited from the precise regulation of ZIF-8 layer through interfacial synthesis and sequential coating of PDMS matrix. The thickness of the PDMS layer was only 16 ± 2 nm, which admirably eliminated the non-selective defects in ZIF-8 layer. Owning to the optimal combination of MOF layer and ultra-thin polymer layer, the as-prepared membrane exhibited the excellent ethanol flux of 1.34 kg m −2 h −1 with an ethanol concentration in permeate of 31.3 wt% for separating 5 wt% ethanol aqueous solution at 40 °C. The separation performance of the resultant membrane was superior to that of the other ethanol selective PV membranes . These findings herein provided a new way for preparing high-performance hollow fiber composite membranes for PV separation.
研究领域:
材料科学
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分离技术
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
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2013
·
IF 4.75
Feifei Hou,Baoan Li,Minghao Xing,Qin Wang,Liang Hu,Shichang Wang
A novel composite hollow fiber membrane for membrane aerated biofilm rector (MABR) was prepared by coating L-3,4-dihydroxyphenylalanine (DOPA) on the surface of PVDF membrane. MABR process study was conducted to test the performances of the original and modified membranes for 166 days. The results indicate that coated membrane showed 2 times higher gas flux, lower water contact angle (declined from 86.5° to 52°), and significantly improved surface roughness. The modified membrane displayed an excellent MABR performance. Its COD, NH 4 + –N and TN removal efficiencies were kept above 90%, 98.8% and 84.2% during the first 4-month experiment. By tracking experiment at 0.01 MPa, to achieve COD removal efficiency of 85.9%, half an hour is required with the modified membrane, instead of 6 h using the original one. Besides, faster NH 4 + –N and TN removal at 0.01 MPa were also achieved with DOPA composite membrane.
研究领域:
环境工程
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材料科学
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Junjie Yang,Wen Sun,Boyu Zhu,Hong Wang,Feng Yan,Jianxin Li,Zhenyu Cui
In this study, polyvinylidene fluoride (PVDF)/styryl maleic anhydride (SMA) hollow fiber membrane was fabricated using the Thermally Induced Phase Separation (TIPS) technique. Subsequently, zwitterion-sulfobetaine methacrylate (SBMA) was introduced to the membrane surface through a Michael addition reaction to create a nearly electrically neutral membrane surface. This modification effectively mitigated the high adsorption of differently charged protein pollutants on the membrane surface, thereby enhancing its anti-fouling performance. Simultaneously, the membrane surfaces with positive and negative charges were separately constructed, and the impact of membrane surface charge properties on the anti-fouling performance against positively and negatively charged foulants was investigated. Furthermore, detailed studies were conducted on the chemical structure, surface morphology, performance, and anti-fouling mechanism of the modified membranes. The results indicate that the electrically neutral membrane modified by zwitterionic SBMA exhibited excellent anti-fouling properties against both bovine serum albumin (BSA) and lysozyme (LYZ), with a flux recovery rate (FRR) reaching 96.5 % and 94.6 %, respectively. The static adsorption capacities of BSA and LYZ on the membrane surface decreased to 5.89 μg cm −2 and 9.53 μg cm −2 , respectively. Furthermore, the study investigated the structure of the hydration layer formed by zwitterionic SBMA on the membrane surface, as well as its hydration capacity and anti-fouling mechanism. Subsequently, through an assessment of the long-term stability of the modified membrane and its flux recovery rate (FRR), in conjunction with theories related to hydration layers and thermodynamics, it elucidated the anti-fouling mechanism involving “autonomy-response” synergistic enhancement of zwitterions. These findings will offer new strategies for researching hollow fiber membranes with superior anti-fouling properties and for applying zwitterions in membrane technology.
研究领域:
膜科学
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材料科学
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化学工程
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环境工程
✓ 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）