NEW JOURNAL OF CHEMISTRY
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2021
·Vol. 45
·期 13
·6108-6119
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IF 3.591
Siyi Li,Xuehui Zhao,Hongwei Zhang
It is very important to reduce the oxidation of free radicals in organic membrane materials for the stability and safety of drinking water production treatment processes. This paper presents a new method for the qualitative and quantitative determination of free radicals in sodium hypochlorite solution by electron spin resonance (ESR) and salicylic acid spectrophotometry. Experiments show that the free radical scavenging rate reaches over 86% after the addition of 0.5 wt% nano-particles. PVDF–PVP/TiO2 and PVDF–PVP/CNT modified membranes are prepared by blending polyvinylidene fluoride (PVDF) with nano titanium dioxide (nano-TiO2) and carboxyl-modified multi-wall carbon nanotubes (MWCNTs-COOH), and are treated in 2000 ppm sodium hypochlorite solution for 30 days. Through surface chemistry (FTIR, XRD), surface morphology (SEM), surface hydrophilicity (contact angle), surface electronegative (zeta potential) and mechanical properties tests, the changes of membrane properties are analyzed during aging. The experimental results show that the nano-particles have a quenching effect on free radicals and inhibit defluorination. It has been proved that under the action of nano-additives, the erosion of free radicals on the membrane material is reduced, the aging rate of the membrane material is decreased, and the chemical stability of the membrane material is improved. In this paper, the reason and mechanism of anti-aging of the nano-particle modified membrane are analyzed, which provides theoretical support for future membrane cleaning technology and prolonging the service life of the membrane.
研究领域:
材料科学
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环境工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
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2015
·Vol. 5
·期 63
·51364-51370
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IF 3.84
Zongxue Yu,Yang Pan,Yi He,Guangyong Zeng,Heng Shi,Haihui Di
As part of this work, polyvinylidene fluoride (PVDF) membranes were prepared via a phase inversion method. A novel β-cyclodextrin (β-CD)–PVDF membrane was prepared via an interfacial reaction, using Trimesoyl Chloride (TMC) and β-CD as cross-linking and modification agents, respectively. The membranes were modified by a simple dip-coating method. The results of comparison between the modified and unmodified membranes by attenuated total reflectance Fourier transform infrared spectroscopy (FTIR-ATR) and X-ray photoelectron spectroscopy (XPS) methods confirmed successful grafting of β-CD on the membrane surfaces. The morphology of the membrane was investigated by scanning electron microscopy (SEM) and atomic-force microscopy (AFM). The roughness of PVDF membranes increased after their surfaces were grafted with β-CD. It was also found that β-CD–PVDF membranes had higher permeate flux and hydrophilicity than those of the pristine PVDF membranes. Furthermore, in protein fouling experiments, bovine serum albumin (BSA) was used as a protein model solution. Modified membranes exhibited a higher flux recovery ratio. The experiment showed that the anti-fouling performance of β-CD–PVDF membranes was more effective in reducing the irreversible membrane fouling. The results of this study hold promise for useful applications of β-CD–PVDF membranes in membrane separation areas.
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
REACTIVE & FUNCTIONAL POLYMERS
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2015
·
IF 2.515
Yanhui Xiang,Yunze Wang,Haibo Lin,Yi Wang,Zhu Xiong,Fu Liu
ABSTRACT Efficient separation of both oil-in-water (O/W) and water-in-oil (W/O) micro-emulsion was accomplished by a novel thermally responsive PVDF membrane. PNIPAAm–PVP–VTES micro-hydrogel was elaborately synthesized and incorporated into PVDF membrane, which was validated by transmission election microscopy (TEM), dynamic light scattering (DLS), X-ray photoelectron spectroscopy (XPS), attenuated total reflection Fourier transformed infrared spectroscopy (FTIR-ATR), laser confocal microscopy and thermogravimetric respectively. The thermally responsive mechanism of the engineered PVDF membrane was proposed from aspects of molecule structure, micro-hydrogel, membrane topology and membrane performance. The permeability and separation efficiency for pure water, both O/W and W/O micro-emulsions were modulated by temperature. The engineered PVDF membrane exhibited superantiwetting, outstanding permeability, high separation efficiency (> 99.90%), excellent antifouling property and reliability for long-term application. Moreover, multistage separation of oil-in-water micro-emulsion was achieved at nano-scale. Dispersed micro-emulsion droplets bigger than 20 nm and 40 nm were completely removed by manipulating the temperature below and above LCST , respectively. The engineered PVDF membrane highlights its great potential in micro-emulsion separation.
研究领域:
材料科学
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环境工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2016
·
IF 5.557
Zhiwei Xu,Tengfei Wu,Jie Shi,Kunyue Teng,Wei Wang,Meijun Ma,Jing Li,Xiaoming Qian,Cuiyu Li,Jintu Fan
A novel graphene oxide/TiO 2 -polyvinylidene fluoride (GO/TiO 2 -PVDF) hybrid ultrafiltration membrane has been successfully developed via the phase inversion technique by supplementing with GO/TiO 2 nanocomposites , in which the synergistic coupling of GO and TiO 2 could result in improved photocatalytic activity and endow hybrid membranes with photocatalytic antifouling function. Compared with PVDF membranes supplemented with TiO 2 and GO, respectively, the GO/TiO 2 -PVDF membrane displayed significantly improved photodegradation efficiency (improved about 50–70%) and superior photodegradation kinetics (1.0–1.5 times faster) toward bovine serum albumin (BSA). Moreover, flux performance and flux recovery ratio of membranes revealed that the GO/TiO 2 -PVDF membrane could recover high flux after fouling, which thus presented self-cleaning property under UV static irradiation. Besides, the GO/TiO 2 -PVDF membrane showed a water flux up to 487.8 L m −2 h −1 , more than 2 times that of the pristine PVDF membrane, while keeping high BSA rejection (92.5%). Therefore, the GO/TiO 2 -PVDF membrane would have good potential in water treatment due to its high-performance multifunctional characters, i.e. separation, photocatalytic oxidation and self-cleaning, etc.
研究领域:
环境科学
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材料科学
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水处理工程
✓ 已验证
产品关联
DOI
高影响因子
BIOFOULING
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2013
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IF 3.396
Xiang Shen,Yiping Zhao,Li Chen
Biofouling of membrane surfaces by the attachment of microorganisms is one of the major obstacles for ensuring the effectiveness of membrane separation processes. This work presents the construction of a zwitterionic PVDF membrane surface with improved resistance to biofouling. An amphiphilic copolymer of poly(vinylidene fluoride)-graft-poly(N,N-dimethylamino-2-ethylmethacrylate) (PVDF-g-PDMAEMA) was first synthesized via radical graft copolymerization and then the flat membrane was cast with immersed phase inversion. The PDMAEMA side chains tended to aggregate on the membrane surface, pore surface and internal pore channel surface, and were converted with 1,3-propane sultone (1,3-PS) to yield a zwitterionic membrane surface. A higher conversion of PDMAEMA chains and distribution of zwitterions were obtained using a longer treatment time. A biofouling assay indicated that incorporation of zwitterions suppressed the adsorption of extracellar polymer substances and the adhesion of Escherichia coli bacterial cells to the membrane surface, endowing the membrane with a high flux recovery and biofouling resistance in the filtration process.
研究领域:
材料科学
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环境工程
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微生物学
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产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
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2017
·
IF 3.387
Li Dong,Xiangdong Liu,Zhengrong Xiong,Dekun Sheng,Yan Zhou,Changhong Lin,Yuming Yang
Herein, PVDF membranes with excellent UV-absorbing property were first synthesized through grafting the polymerizable low-molecular-weight organic UV-absorber 2-hydroxy-4-(3-methacryloxy-2-hydroxylpropoxy) benzophenone (BPMA) onto α-bromoester-functionalized PVDF membranes via the surface-initiated activator generated by electron transfer atom transfer radical polymerization (SI-AGET ATRP). The surface initiators were immobilized by the reaction between 2-bromoisobutyryl bromide (BIBB) and the hydroxylated PVDF membranes. PVDF-g-PBPMA membranes with different grafting densities were obtained by tuning the polymerization time and the modified membranes were characterized by 1 H-NMR, FT-IR, XPS, SEM, UV–vis Spectrophotometer, TGA and DSC. The experimental results indicated that PBPMA chains were successfully introduced onto PVDF membranes. Most importantly, the PVDF-g-PBPMA membranes exhibited outstanding UV-shielding property. UV–vis transmittance spectra showed that most UV light below 360 nm could be absorbed by PVDF-g-PBPMA membranes and the whole UV light region (200–400 nm) can be blocked with the reaction time increased.
研究领域:
材料科学
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高分子化学
✓ 已验证
产品关联
DOI
高影响因子
ACS ES&T Water
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2022
·
IF 0
Shuangling Xie,Jiale Du,Xuan Huang,Ailiang Gu,Shengqiong Fang,Riri Liu,Dong Zou,Jiuyang Lin,Ming Xie,Shuaifei Zhao,Wenyuan Ye
Membrane distillation (MD) has been widely used for resource recovery from high-salinity wastewater, due to its superior technical merits of high separation efficiency and potential integration of low-grade heat. Herein, a robust superhydrophobic PVDF membrane prepared by spray-coating of fluorinated silica nanoparticles was employed to treat highly saline dye wastewater by MD. Specifically, impacts of operation conditions, including temperature difference, feed flow-rate, salinity, dye concentration, and dye species, on MD performance of the fabricated superhydrophobic PVDF membrane were comprehensively investigated. The increase of temperature difference and feed flow-rate had a positive effect on the MD flux of the membrane. Conversely, the rise in salinity and dye concentration induced an adverse impact on the MD flux. Furthermore, the superhydrophobic PVDF membrane showed a strong robustness in treating complex streams, as demonstrated by consistently stable MD flux using various dye/NaCl mixed solutions. Due to the robust surface superhydrophobicity, the fabricated PVDF membrane exhibited impressive antiwetting and antifouling properties against highly saline dye wastewater, consistently stable permeation flux, and high dye/salt removal efficiency (>99.99%). Moreover, the superhydrophobic membrane showed a high water recovery (90%) from highly saline dye wastewater with a slight reduction (13.4%) in permeation flux during a 39 h MD filtration. These results signify the promising practicability of the fabricated superhydrophobic PVDF membrane in sustainable management of highly saline dye wastewater via MD.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
JOURNAL OF MEMBRANE SCIENCE
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2023
·
IF 9.5
Hongai Zheng,Mengyao Li,Shuangyan Jiang,Cunzheng Xiao,Meilin Zhu,Yao Zhou,Derui Wang,Xin Sun,Daquan Zhang,Lizhi Zhang
Herein, the MIL-88A/Carbon quantum dots (CQDs) was synthesized by a hydrothermal method , and the polyvinylidene fluoride (PVDF) membrane modified by the MIL-88A/CQDs was fabricated by vacuum-assisted suction filtration. Compared with the pristine membrane, MIL-88A/CQDs modified membrane based on collaborative photo-Fenton/filtration process shows better removal efficiency for methylene blue (MB), rifampicin (RIF), methyl orange (MO), and Rhodamine B (RhB). In addition, the anti-fouling properties of the modified membrane are significantly improved, and the flux recovery of the MIL-88A/CQDs modified membrane increased from 56% to 89%, and the irreversible fouling ratio (R ir ) decreased from 44% to 11%. Significantly, the modified membrane contaminated by MB within 20 min can achieve self-cleaning through the photo-Fenton process. Finally, a possible membrane antifouling mechanism is proposed: superoxide radicals (•O 2 - ) and hydroxy radicals (•OH) are the main active substances. CQDs accelerates the e − and h + separation of MIL-88A and promotes the circulation of Fe substances. The fundamental research will present a promising strategy for improving antifouling properties of membrane.
研究领域:
材料科学
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环境工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 30
·23530-23539
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IF 3.84
Yanhui Xiang,Jianhui Shen,Yunze Wang,Fu Liu,Lixin Xue
Responsive materials with surfaces that have controllable oil wettability under water offer considerable potential in advanced applications. We have developed an economical and convenient method for constructing a superwetting polyvinylidene fluoride (PVDF) membrane, giving super-hydrophobicity under oil and super-oleophobicity under water. The membrane has been achieved by incorporating pH-responsive N,N-dimethylaminoethylmethacrylate (DMAEMA) hydrogels into PVDF using a combination of in situ polymerization and conventional phase separation. In pure or acidic water the poly-DMAEMA chains modify wettability by the protonation or deprotonation of their tertiary amine side-groups, affecting the wettability of the membrane under water. In addition, this responsive membrane has been utilized for the separation of surfactant-stabilized water-in-oil and oil-in-water emulsions. High flux and separation efficiency can be obtained, together with excellent antifouling properties, suggesting that the membranes will find wide application in the separation of oil and water systems.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
ChemistrySelect
·
2025
·Vol. 10
·期 13
·e202405849
·
IF 2
Juan Dai,Qixu Chen,Yue Li,Jin Wang,Yanchao Yin,Peiyu Zhao,Peichuang Li,Luying Wang
Graphical A defect-free PVDF/ZIF-8-LS membrane prepared by loading a continuous ZIF-8-LS film layer on the PVDF membrane exhibited high and stable adsorption performance for CR and TC removal, because of a good compatibility between PVDF membrane and ZIF-8-LS layer. Lignosulfonate (LS) enhances ZIF-8 dispersion and active sites but faces challenges in recovery and secondary pollution due to its powdered form. To address this, a polyvinylidene fluoride (PVDF)/ZIF-8-LS composite membrane was fabricated via vapor deposition, where LS promoted dense ZIF-8 growth and interfacial compatibility with PVDF. The resulting PVDF/ZIF-8-LS membrane shows a higher continuous, uniform and dense ZIF-8-LS layer without macroscopic cracks or obvious defects. In addition, the PVDF/ZIF-8-LS exhibits the best adsorption capacity of 110.6 mg g −1 for Congo Red, about 8.8 mg g −1 higher than the PVDF/ZIF-8, and 110.2 mg g −1 for tetracycline, respectively. With 92% capacity retention after three cycles and stability across pH 2–10. The more active adsorption sites facilitates the contact between the ZIF-8-LS layer and the adsorbed substance, in addition to the electrostatic, H-bonding, π-π interactions, and coordination bond are also conductive to the adsorption of PVDF/ZIF-8-LS. The excellent adsorption performance and good recyclability of the PVDF/ZIF-8-LS composite membranes exhibit a potential for adsorbing other contaminants from water.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Chang Li,Yanbin Yun,Fengguang Huang,Jiaming Mao,Jia Liu,Wenjuan Yang,Chunyun Zhou,Meng Li
The membrane contact absorption method is a promising technology for carbon dioxide (CO 2 ) capture, enhancing absorption efficiency and mitigating aerosol emissions. However, membrane wetting, an inevitable issue during the membrane contact absorption process, leads to a rapid decline in absorption rates, thereby limiting the development of this methodology. Focusing on the tendency of organic absorbents to induce membrane wetting, this study reports a novel modification method for amphiphobic polyvinylidene fluoride (PVDF) membranes. This method leverages polydopamine nanoparticles (PDANPs) to construct stable multi-level reentrant structures on the membrane surface, which are further enhanced for their hydrophobic properties through surface fluorination. The resultant amphiphobic membrane exhibits exceptional resistance to both water and organic wetting, with a water contact angle as high as 152.82° and contact angles above 90° for various organic absorbents. Long-term experiments demonstrate that the membrane material prepared by this method facilitates the stable and long-running operation of membrane contactors. Based on these findings, we analyze the structure–property relationship between the membrane surface microstructure and its amphiphobic performance. In conclusion, the fluorinated polydopamine hierarchical structure effectively resists membrane wetting induced by CO 2 absorbents, contributing to the promotion and application of CO 2 membrane absorption technology
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2019
·
IF 6.361
Jinhui Huang,Jianglin Hu,Yahui Shi,Guangming Zeng,Wenjian Cheng,Hanbo Yu,Yanling Gu,Lixiu Shi,Kaixin Yi
Recently, the application of membranes faces a big challenge due to membrane fouling, to alleviate this situation, the hybridization of photocatalysis and membrane filtration has aroused significant attention. In this study, we firstly introduced melamine, cyanuric acid and urea in dimethyl sulfoxide (DMSO) as precursors to fabricated the MCU(DMSO)-C 3 N 4 material with excellent photocatalytic performance, and immobilized it on PVDF membranes by vacuum filtration, subsequently adding polyethylene glycol and glutaraldehyde as crosslinkers from MCU-C 3 N 4 /PVDF membrane. The results demonstrate that with the MCU-C 3 N 4 ratio increasing, the membrane flux was gradually decreased. Besides, the photocatalytic efficiencies of MCU-C 3 N 4 /PVDF for rhodamine B (RhB) and tetracycline hydrochloride (TC) degradation are 84.24% and 71.26% respectively, which are about 8 times higher than that of the original membrane. To evaluate antifouling performance of photocatalytic membranes, we conducted a four-stage filtration system, and the flux recovery ratio (FRR) of MCU-C 3 N 4 /PVDF membranes reached over 80% (optimum 91%) under visible light irradiating (λ > 420 nm) for 30 min. Meanwhile, under visible light irradiation reversible fouling (Rr) gradually became the dominant fouling factor instead of the irreversible fouling (Rir), indicating the excellent antifouling performance of MCU-C 3 N 4 /PVDF membranes. This novel method to modify membranes with MCU-C 3 N 4 gives insight to photocatalytic and self-cleaning properties of photocatalytic composite membranes, providing theoretical basis for their broad application.
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
危险品化学品经营许可证（带存储）