JOURNAL OF MEMBRANE SCIENCE
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2019
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IF 7.015
Ji-Hao Zuo,Zhong-Kun Li,Chao Wei,Xi Yan,Yan Chen,Wan-Zhong Lang
The PVDF membranes were prepared via thermally induced phase separation (TIPS) method with saline water as quenching bath and applied to the separation of oil/water emulsions. Surface pore size, permeation performance and other properties of the PVDF membranes were finely tuned by adjusting salt concentration in quenching bath. The results show that with the addition of NaCl in quenching bath, the thermal transfer resistance increases in the TIPS process due to the obvious increase of bath viscosity and the slight decline of thermal conductivity of saline solution. All the PVDF membranes present bi-continuously fibrillar structure in top surfaces. The fibrils are fused together and get thicker, and leads to rougher top surfaces due to the decline of cooling rate with the addition of NaCl in quenching bath. At the same time, the PVDF membranes exhibit expanded pore size and higher permeation flux for both pure water and oil/emulsions. The PVDF membrane of S20 (prepared with 20 wt% NaCl aqueous solution as quenching bath) exhibits the largest mean pore size and the highest pure water permeation flux of 2481.1 L m −2 h −1 bar −1 . However, overhigh NaCl content leads to the inverse trend. For example, the PVDF membrane of S30 (quenching bath containing 30 wt% NaCl) exhibits a lightly decreased pore size and pure water permeation flux compared to S20. All of the PVDF membranes exhibit good oil rejections above 90.0% for surfactant-stabilized oil-in-water emulsions and above 95.0% for surfactant-free oil-in-water emulsions.
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高影响因子
APPLIED SURFACE SCIENCE
·
2018
·
IF 4.439
Jian-Hua Li,Xing-Xing Ni,De-Bin Zhang,Hui Zheng,Jia-Bin Wang,Qi-Qing Zhang
A facile and versatile approach for the preparation of super-hydrophilic, excellent antifouling and hemocompatibility membranes had been developed through the generation in situ of bio-inspired polydopamine (PDA) microspheres on PVDF membranes. SEM images showed that the PDA microspheres were uniformly dispersed on the upper surface and the lower surface of the modified membranes. And there were a great number of PDA microspheres immobilized on the cross-section, but the interconnected pores structure was not destroyed. These facts indicated the existence of membrane micro-reactor effect for the whole membrane structure. Considering the remarkable improvement of hydrophilicity, antifouling properties, and permeation fluxes, we also proposed the cluster phenolic hydroxyl effect for the PVDF/PDA hybrid membranes. And the cluster phenolic hydroxyl effect can be ascribed to the all directions distributed phenolic hydroxyl groups on the whole membrane structure. Besides, the self-driven filtration experiments showed the great wetting ability and permeability of the PVDF/PDA hybrid membranes in filtration process without any external pressure. This implied the existence of accelerating self-driven force after the water flow flowed into the internal of membranes, which contributed to the increase of water flow velocity. All the three aspects were in favor of the enhancement of hydrophilicity, antifouling properties and permeability of the modified membranes. Moreover, the conventional filtration tests, oil/water emulsion filtration tests and protein adsorption tests were also carried out to discuss the practical applications of PVDF/PDA hybrid membranes. And the hemocompatibility of the modified membranes was also proved to enhance greatly through the hemolysis tests and platelet adhesion tests, indicating that the membranes were greatly promising in biomedical applications. The strategy of material modification reported here is substrate-independent and can be extended to other substrate materials, and allows the development of novel functional membranes through secondary treatments.
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高影响因子
Results in Engineering
·
2024
·
IF 6
Ziteng Feng,Tong Wang,Yakai Lin,Lin Wang,Yuanhui Tang,Huanhuan Wu,Hedi Chen,Lixin Yu,Xiaolin Wang
Polyvinylidene fluoride (PVDF) membranes, widely used for their stability, face limitations due to the hardly adjustable pore size in nanoscale and inherent hydrophobicity. To address this, we proposed a co-deposition method incorporating dopamine (DA), polyethyleneimine (PEI), and silicon dioxide (SiO 2 ) nanoparticles with glutaraldehyde cross-linking for precise regulation of pore size and hydrophilicity in PVDF hollow fiber membranes. Notably, the pore diameter reduced from 119.0 ± 3.55 nm to 18.4 ± 0.36 nm, while the contact angle decreased from 107.7° to 40.9°. This simultaneous regulation led to a high-performance PDA/PEI/SiO 2 -PVDF hydrophilic ultrafiltration membrane with a rejection rate exceeding 99% for 20 nm nanoparticles in a long-term simulated separation experiment while achieving a significant protein permeability of 97% in BSA permeation experiments. Additionally, the membrane demonstrated exceptional long-term stability, offering a novel approach for tuning the performance of ultrafiltration/microfiltration membranes.
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高影响因子
FIBERS AND POLYMERS
·
2017
·Vol. 18
·期 9
·1754-1762
·
IF 1.113
Zhang Bin,Jiang Yujie,Han Jian
Selective separation is an effective method for the removal of heavy metal ions and waste oil from wastewater. Polyvinylidene fluoride (PVDF) was functionalized with polyvinyl acetate (PVAc) by in-situ polymerization, and novel PVAc-g-PVDF coating on surface modified cotton fabric were prepared. The contact angle (CA), pure water flux (PWF) and self-cleaning ability of coated cotton fabric were investigated in detail. In addition, the separation performance of coated cotton fabric was reflected by the removal of heavy metal ions in simulated wastewater. The results revealed that the PVAc-g-PVDF-coated cotton fabric was free of waste oil adhesion and was self-cleaning from waste oil in aqueous environment. Meanwhile, this coated cotton fabric can effectively separate oil/water mixtures with a high flux and high oil rejection, and was easily recycled for long-term use. More importantly, the heavy metal ions rejection ratio and adsorption capacity of cotton fabric were also improved with the addition of PVAc-g-PVDF coating. PVAc-g-PVDF-coated cotton fabric exhibited excellent rejection stability and reuse performances after several times fouling and washing tests. It can be expected that the present work will provide insight into a scaled-up fabrication process of PVAc-g-PVDF coating for purifying wastewater.
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高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Mingchun Bi,Yuning Liang,Weimeng Chi,Hongya Liu,Ying Chen
Nano zero-valent iron (nZVI) is extensively employed in the realm of wastewater treatment. However, conventional synthesis methods involve inherent risks of nZVI oxidation and aggregation, resulting in challenging recovery and potential waste generation. To address these concerns and improve stability, nano zero-valent nickel (nZVNi) was employed as a modifier for nZVI. The modified nZVNi/nZVI was successfully blended with polydopamine (PDA)-modified polyvinylidene fluoride (PVDF) powder, enabling the preparation of a novel hydrophilic composite membrane termed nZVNi/nZVI-PDA@PVDF (NFPP). PDA played a crucial role in effectively immobilizing nZVI particles and preventing their oxidation and aggregation. Scanning electron microscopy was used to confirm the consistent dispersion of nZVNi/nZVI particles both on the surface of the membrane and within its pores. Moreover, the NFPP membrane exhibited excellent performance in removing Cr(VI), with a maximum adsorption capacity of 75.65 mg/g. The presence of PDA endowed the NFPP membrane with a plentiful supply of hydroxyl and amino groups, enhancing its hydrophilicity, antioxidation properties, and loading capacity for nZVNi/nZVI. Additionally, the NFPP membrane demonstrated remarkable resistance to interference under different pH and ionic conditions. The removal of Cr(VI) by the NFPP membrane followed a pseudo-second-order kinetics and Langmuir isotherm adsorption model. Furthermore, the NFPP membrane retained good performance and stability in Cr(VI) removal even after undergoing five cycles. This study indicates that the highly efficient NFPP composite material holds promising potential for application as a functional material in heavy metal wastewater treatment.
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高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
·
IF 8.1
Jingcheng Wu,Yi He,Yiling He,Wanwan Peng,Daqing Wu
Recently, oily wastewater has become an urgent cross-regional problem. Membrane technology is considered a sound solution to this crisis. However, membrane fouling causes a sharp decrease in water permeance and service life, which greatly restricts membrane applications. In addition to a few degradable materials, the most severely polluted membranes are burned or buried in the soil, wasting resources and accelerating ecological damage. Inspired by Guandong candy, we reported a novel, facile, and green approach to construct composite polyvinylidene fluoride (PVDF) membranes with stable self-cleaning, anti-oil-fouling, and photocatalytic recovery properties for efficient oil-in-water emulsions separation. Due to the synergistic effect of the superhydrophilic tin dioxide/titanate nanotubes (SnO 2 /TNTs) and Guandong-candy-inspired electrolessly welding organic–inorganic hybrid colloids, the composite PVDF membrane showed remarkable stability and underwater oil-repellency properties. Accordingly, the composite PVDF membrane achieved excellent water permeance (>2600 L m −2 h −1 bar −1 ), superior separation efficiency (>99.6 %), and long-term antifouling performance during soybean oil-in-water emulsion separation. More importantly, the composite PVDF membrane exhibited highly efficient self-cleaning and recovery of the PVDF membrane and SnO 2 /TNTs under visible-light irradiation. Within the framework of green and sustainable concepts, this is a novel reusable idea for the recyclable utilization of commercial PVDF membranes and photocatalytic minerals in oily wastewater purification.
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高影响因子
JOURNAL OF POWER SOURCES
·
2025
·
IF 7.9
Yan He,Jinpeng Guo,Chuanchuan Bi,Zhifei Hao,Bin Zhao,Chunping Li,Xiaogang Han,Qi Wang
Composite polymer electrolytes (CPE) have attracted considerable attention due to their potential to achieve high flexibility and large energy density. However, their practical application is hampered by their suitability at a single temperature and severe lithium dendrite growth. In this work, we have doped the perovskite inorganic filler LaCoO 3 into polyamide (PI) nanofibers and constructed a LaCoO 3 /PI/PVDF CPE. Electrochemical characterization of the CPE and density functional theory calculations performed for it show that perovskite nanofibers have abundant oxygen vacancies, which are conducive to accelerating the dissociation of lithium salts and releasing more free lithium ions. Li//Li symmetric batteries exhibit excellent long cycle performance (over 3000 h) at 30 °C, and LiFePO 4 //Li batteries exhibit excellent cycling performance with over 1000 cycles at (0.5 C, 30 °C) and 400 cycles at (0.2 C, 60 °C), which can be realized with high voltage cathode NMC 811. The physical properties of the CPEs are also quite outstanding, with good thermal stability as it can withstand a high temperature of 200 °C and tensile strength up to 12.01 MPa. This work presents a new idea for designing CPEs with high safety and excellent electrochemical properties, which can provide stable circulation over a wide temperature range.
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高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
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2024
·
IF 8
Xianhua Liu,Miao Liu,Yexin Dai,Jinran Cui,Asad Jamil,Wanxin Liu,Jiaxuan Li,Jiao Wang
Constructing a photocatalytic membrane and photo-Fenton reaction coupling system is a novel strategy to enhance the photocatalytic activity of the membrane and eliminate the problem of membrane contamination. Herein, a g-C 3 N 4 /Bi 2 MoO 6 /PVDF photocatalytic membrane was prepared using a tannic acid-assisted in-situ deposition method. The membrane was characterized by three advantages of photocatalytic, self-cleaning, and antibacterial properties. Under the photo-Fenton-like conditions, the membrane had superior photodegradation efficiency of 90.7% for tetracycline, one of the main antibiotic contaminants in the China's aquatic system. Moreover, the membrane had excellent photo-Fenton self-cleaning ability, its flux recovery rate was up to 96%–98% after the self-cleaning process. Photoluminescence spectra, diffuse UV–visible spectrum, transient photocurrent responses, and electrochemical AC impedance spectrum results show that the heterojunction structure formed by g-C 3 N 4 and Bi 2 MoO 6 could improve the separation efficiency of photogenerated electrons-hole pairs. Electron spin resonance spectroscopy confirmed the photo-electrons facilitated the formation of hydroxyl radical (·OH) in the existence of H 2 O 2 , which enhanced tetracycline degradation. Moreover, the superior photo-Fenton self-cleaning performance, which mainly relied on the active free radicals produced by the photo-Fenton-like membrane to remove dirt on the membrane surface or in the membrane pore channel. Our results may shed new light on the development of promising photocatalytic membrane systems by coupling with photo-Fenton-like processes, and facilitate their applications for wastewater treatment .
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PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Zheng Li,Xin Song,Wenke Li,Xiaolong Ding,Lianjie Li,Meijun Liu,Lanhe Zhang,Chuntao Zhu,Zicheng Chen
A novel lithium (Li) ion-imprinted composite membrane (IIP@PPy/rGO@PVDF) was developed for the selective recovery of Li + through an external-voltage-driven process. This membrane was synthesized by integrating ion-imprinting technology with electrochemically switched ion exchange technology, presenting a highly promising technique for the efficient extraction of Li from brine. The IIP@PPy/rGO@PVDF membrane consisted of polypyrrole (PPy), reduced graphene oxide (rGO), 12-crown 4-ether (12C4), and ethylene dimethacrylate (EDGMA). Furthermore, leveraging the electric field and specific recognition of 12C4 toward Li + , the membrane exhibited excellent ionic adsorption performance, including a high adsorption capacity of 214 mg.g −1 , a superior retention ratio (Maintaining the initial value even after 10 cycles of electrochemical adsorption–desorption), a short equilibration time of <25 min, and an adsorption capacity of 98 mg.g −1 at pH = 1. Subsequently, variations in the average heat of adsorption indicated that the electric field enhanced the adsorption performance. These performances were attributable to the synergistic effects of rGO with PPy. Therefore, IIP@PPy/rGO@PVDF serves as an outstanding candidate for Li extraction in environments with high applied voltages and strong acidity.
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高影响因子
Journal of Water Process Engineering
·
2025
·
IF 6.7
Bingxin Zhang,Yantao Song,Xu Cao,Zhenyu Cui
In this work, the method of “vacuum filtration-physical adhesion” is used to uniformly load TiO 2 nanoparticles on the polymer membrane surface to form a continuous and uniform TiO 2 nanoparticle coating layer. Two distinct PVDF/SMA@TiO 2 hybrid membranes featuring diverse surface microstructures were prepared. The oil fouling resistance of the two membranes and their influence on oil droplet adsorption behavior were examined. The results indicated that introduction of TiO 2 nanoparticles imparts the membrane surface with a nano-rough structure while ensuring superhydrophilicity, features that inhibit oil droplet adhesion. The membrane achieved a flux recovery rate of 97.12 % and an oil removal efficiency of 98.9 %, demonstrating superior anti-fouling and separation capabilities. At the same time, the multiple synergistic mechanisms including a hydrophilic layer formed by continuous TiO 2 nanoparticles, low surface roughness, rigid structure of nanoparticles and electrostatic interaction effectively destroy the surface charge of the surfactant stabilized oil droplets, which results in the coalescence of small-size emulsion oil droplet into large-size oil droplet with less surfactant and relatively weak charge. Finally, the interfacial interaction at the oil droplet-membrane interface is attenuated. Based on these, the anti-fouling mechanism of “cooperative repulsion-charge weakening” was proposed. This research offers a theoretical foundation for designing high-performance hybrid membranes for oil-water separation.
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高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2025
·Vol. 36
·期 22
·1-15
·
IF 2.8
Zhou Hengqing,Li Xiao,Gao Guoqi,Sun Huajun,Liu Xiaofang
BiOBr/PVDF composite films with different precursor doping amounts were successfully prepared by in situ deposition phase conversion technology. The physicochemical properties of the composite films were analyzed in detail, and their piezoelectric-photocatalytic performance was systematically investigated. The experimental results showed that BP-0.8 (with a doping amount of 0.8 mmol for the BiOBr precursor) exhibited the best catalytic performance. Under the synergistic effect of visible light irradiation and ultrasonic vibration, the degradation rate of BP-0.8 for 50 mL of 40 mg/L Rhodamine B (Rh B) solution within 60 min could reach 96.73%, and the apparent reaction rate constant (k) of this sample was 0.06198 min⁻ 1 . It was 3.81 times and 27.06 times that of photocatalysis alone and piezoelectric catalysis alone, respectively. The radical capture experiment proved that the main active groups involved in the reaction were h⁺ and ·OH, and the mechanism of piezoelectric photocatalysis of BiOBr/PVDF composite thin films was proposed. In addition, compared with powder catalysts, flexible BiOBr/PVDF membranes were easier to recycle, did not require complex treatment, and still maintained good catalytic activity after ten cycles of testing. This work demonstrated the contribution of the piezoelectric effect to photocatalytic water purification and provided a promising strategy to utilize solar and mechanical energy.
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高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2024
·Vol. 31
·期 55
·63800-63818
·
IF 0
Fan Wenling,Wu Jiali,Sun Long,Gao Meiqi,Zhang Xiaotong
In the realm of oil–water separation technologies, membrane-based separation emerges as an efficacious approach. Nevertheless, crafting a hydrophilic membrane capable of effectively segregating herbal volatile oil remains a formidable challenge. Our study introduces a facile in situ assembly strategy for fabricating a double-crosslinked composite coating comprising phytate (PA)-polyethyleneimine (PEI) polyelectrolyte complexes and PA-Fe 3 ⁺ assemblies. The PA within the PA-PEI/Fe 3 ⁺ coatings form a double cross-linking layer through interactions with amine groups and metal ions, thereby enhancing interfacial interactions and structural integrity of the membranes. Consequently, the resultant PVDF/PA-PEI/Fe 3 ⁺ membranes exhibit improved coating stability, pronounced hydrophilicity, and exceptional antifouling capabilities, rendering them highly suitable for the separation of diverse herbal volatile oil-in-water emulsions. Furthermore, they possess the capability for reuse with an average retention ratio exceeding 90% and a pure water flux reaching up to 3200 L·m⁻ 2 ·h⁻ 1 . Additionally, they demonstrate long-term stability and resistance to corrosion. With a simplistic yet efficient preparation process, the PVDF/PA-PEI/Fe 3 ⁺ membrane holds significant potential for the extraction of oils from herbal volatile oil-in-water emulsions.
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