CHEMOSPHERE
·
2022
·
IF 8.943
Xiaoju Yan,Chengyu Yang,Cong Ma,Hui Tao,Shirong Cheng,Lin Chen,Guodong Wang,Xinping Lin,Chengzhi Yao
Membrane fouling and wetting limit the applications of membrane distillation (MD) for wastewater treatment , especially when treating the wastewater with a high concentration of low surface tension substances such as oil and surfactants. In this paper, virgin polyvinylidene fluoride (PVDF) membrane was modified by polydimethylsiloxane (PDMS) to enhance anti-wetting ability. Then a thin polydopamine (PDA) layer was coated as a reaction platform for further modification. Polyethyleneimine (PEI) was cross-linked with PDA to form a uniform and stable layer, through hydrogen bonds and electrostatic interaction to immobilize hydrophilic MXene, which formed a Janus MXene-PVDF membrane. The MXene layer was the key for superoleophobicity and high liquid entry pressure (LEP) of membrane, capable of mitigating membrane fouling and wetting when dealing with low surface tension wastewater (LSTW). From the experiments results, pristine PVDF membrane showed severe fouling and wetting with flux decline and salt leakage during treatment of LSTW (surfactants containing water, oil-in-water emulsion and sodium dodecyl sulfate stabilized oil-in-water emulsion). However, under the same conditions, the Janus MXene-PVDF membrane exhibited remarkably stable flux (9.3 kg m −2 h −1 , 9.1 kg m −2 h −1 , 10.2 kg m −2 h −1 ) and salt rejection (almost 99.9%) after 15 h operation. Excellent fouling and wetting resistance of MXene-PVDF membrane was mainly attributed to its superhydrophilic and superoleophobic top surface (in-air water contact angle: 30.2°, under-water oil contact angle: 169.9°) and hydrophobic substrate (in-air water contact angle: 130.8°), together with high LEP value (91.1 Kpa). This study provides a viable route to fabricated a Janus membrane with outstanding fouling and wetting resistance for LSTW, oily wastewater and it has great potential for sewage treatment in the future.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Xiaojia Zhao,Junjie Fu,Fangqian Yin,Chaoqun Li,Yuyang Xu,Guirong Peng
A one-step co-deposition method based on dopamine and hydrophilic hydroxyethyl methacrylate (HEMA) was proposed for the modification of polyvinylidene fluoride (PVDF) membrane, which could ameliorate its oil-water separation performances and hydrophilicity. A range of modified membranes were prepared by adding different content of HEMA in the reaction solution. For the improved membrane, the minimum water contact angle can reach 13.63°, and the maximum underwater oil contact angle can reach about 150°. The pure water flux for the improved membrane reaches 9668 L·m -2 ·h -1 ·bar -1 , showing excellent hydrophilicity. In addition, the separation efficiency of the improved membrane for a variety of oil-water emulsions exceeds 98%, indicating good permeability and circulating oil resistance. At the same time, this approach is also applicable to other membranes on account of the extensive availability of dopamine.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
·
2025
·
IF 6.7
Chen Zhao,Yiheng Wang,Nianping Wang,Ruilin Chen,Rui Yin,Xiangxi Li
The in-situ growth of ZnO is often used to modify membrane surface for enhanced hydrophilic and antibacterial properties due to significant modification effect, simple process and low cost. Nonetheless, some polymer membranes (such as PVDF membrane) lack active sites for ZnO growth on their surfaces, resulting in a small number of particles and unstable binding. This study utilized PDA/PEI to modify PVDF membranes for adequate active sites to capture Zn 2+ ions via the chelation action. Thereafter, nano ZnO can be synthesized easily via the alkalization reaction and thermal breakdown of Zn 2+ . Upon improving the modification conditions, ZnO particles were evenly distributed on the PVDF membrane's surface, leading to a reduction in membrane pore size from 0.38 nm to 0.29 nm. The water contact angle of the ZnO/PDA-PEI modified membrane dropped from 130° to 19°, indicating a significant enhancement in hydrophilicity. The modified membrane demonstrated enhanced anti-fouling performance in the oil/water separation experiment, achieving a steady permeance of 298 L·m −2 ·h −1 ·bar −1 , which was sixfold that of the original membrane. In the antibacterial experiment, the modified membrane exhibited significant antibacterial efficacy against both E. coli and S. aureus .
研究领域:
材料科学
·
环境工程
·
生物学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Xueting Zhao,Youyou Lan,Kai Yang,Ruoxi Wang,Lijuan Cheng,Congjie Gao
This study proposes a novel strategy to fabricate antifouling UF membrane with integrated zwitterionic and TiO 2 functionality via in situ mixed-charge copolymerization and TiO 2 mineralization. The mixing of positively and negatively charged monomers at the molecular level endows membrane surface with balanced mixed-charge zwitterionic functionality, and the in situ TiO 2 mineralization endows membrane surface with well-dispersed TiO 2 nanoparticles. Thanks to the unique hydrophilicity of mixed-charges and TiO 2 , the obtained PVDF/P(MAA-TA)-TiO 2 membrane shows greatly enhanced surface hydrophilicity. The outstanding hydrophilicity of the PVDF/P(MAA-TA)-TiO 2 membrane significantly improves permeability and protein rejection compared to that of the unmodified PVDF membrane. What's more, the PVDF/P(MAA-TA)-TiO 2 membrane exhibits excellent antifouling capability against protein with flux recovery rate and fouling removal efficiency about 100%. Results of detailed fouling analysis indicate that both surface fouling and pore fouling were limited on the PVDF/P(MAA-TA)-TiO 2 membrane. The antifouling performance is mainly attributed to the synergistic hydrophilicity of mixed-charges and TiO 2 , and meanwhile the decrease in the surface electronegativity and pore size also plays a role. Results of this study provide a facile and scalable method for designing antifouling UF membrane, and highlight the promising potential of mixed-charges and TiO 2 synergy for manipulating hydrophilic and antifouling modification of UF membranes.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Gongduan Fan,Chongguo Chen,Xiaolei Chen,Zhongsheng Li,Shulei Bao,Jing Luo,Dingsheng Tang,Zhongsen Yan
Ultrafiltration is an environmentally friendly water treatment technology, but membrane fouling significantly impacts membrane performance and service life. Photocatalytic modification of membrane is regarded as an effective way for membrane fouling control. In this study, graphite oxide (GO), Ag 3 PO 4 and Ag 3 PO 4 -GO nanomaterials were applied in polyvinylidene fluoride (PVDF) ultrafiltration membranes modification, and the membranes was denoted as P-GO, P-AgP and P-AgP@GO, respectively. Filtration of humic acid (HA) at different operating conditions was adopted in evaluation of membrane performance. Among them, P-AgP@GO had the best permeation, rejection and antifouling performances, and could maintain excellent properties when operation conditions (HA concentration, operation pressure, pH and ionic strength) were changed. Furthermore, the effect of photocatalysis on the self-cleaning performance and its mechanism were revealed. The overall performance of P-AgP@GO could be enhanced by visible light irradiation, and extending the visible illumination time during the filtration was conducive to the reusability.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER ENGINEERING
·
2024
·
IF 1.7
Ziyu Liu,Yanqing Liu,Chong Zhang,Takashi Sakamaki,Xianning Li
Conductive filter membranes have shown great potential in alleviating membrane fouling. In this study, polypyrrole (PPy) was used as the conductive material and sodium anthraquinone-2-sulfonate (AQS) was used as the dopant to perform surface modification on the PVDF membrane. After modification, the contact angle of the membrane decreased from 79.40° to 48.57°, and the electrical conductivity of membrane increased from zero to 1.60 S/cm. The good hydrophilicity and electrical conductivity of PPy-AQS/PVDF endowed it with superior antifouling capabilities, reducing the static protein (BSA) adsorption from 0.147 mg/cm 2 to 0.097 mg/cm 2 . Under the action of an electric field of −0.1 V, the flux decay rate of PPy-AQS/PVDF decreased, and the flux recovery rate improved.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 38
·24670-24680
·
IF 4.036
Wei Qin,Along Yu,Xue Han,Junwei Wang,Jiayin Sun,Jianli Zhang,Yaqing Weng
With the increasing demand for rare earth elements (REEs) due to their wide application in high technology, their recovery and separation from waste sources has gradually come onto the agenda. Herein, a new kind of MIL-101-NH2 (M1N) MOF functionalized with diethanol anhydride (DGA) incorporated into a polyvinylidene fluoride (PVDF) membrane (DGA-M1N@PVDF) has been fabricated for the sorption of REEs from a simulated acid leaching solution of waste phosphor, which contains a large amount of REEs. FTIR, TGA, XRD, fluorescence spectra and XPS analysis were used to characterize the synthesized composite membrane. Batch tests were employed to determine the optimal sorption conditions for Y and Eu adsorbed on DGA-M1N@PVDF adsorbent, such as pH (1–5), content of M1N MOFs (0–40 wt%), contact time (10–180 min) and ion concentration (0–20 mg L−1). Maximum adsorption capacities for Y and Eu on DGA-M1N@PVDF reached 991.7 μg g−1 and 98.76 μg g−1 for trace REE solution, respectively. Moreover, a pseudo-second-order kinetic model accurately described the sorption process, and the plotted isothermal data indicated that the Langmuir model was more suitable than the Freundlich model for Y and Eu sorption with monolayer and chemical adsorption. Meanwhile, FTIR and XPS analyses revealed that the Y and Eu adsorption on the DGA-M1N@PVDF composite membrane was mainly caused by the N and O atoms of the –CONH or –COOH groups coordinated with metal ions. Furthermore, after five cycles, the recovery efficiency by DGA-M1N@PVDF for REEs remains above 82% and the XRD patterns were consistent with the original sample, which implied that the DGA-M1N@PVDF membrane has preferable stability, recyclability and good efficiency in REE separation from waste phosphor solutions.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
Journal of Water Process Engineering
·
2024
·
IF 6.3
Lei Cao,Hongpeng Liu,Haoyu Li,Huiming Lin,Lingfei Li
Microfiltration membrane separation technology has been widely employed in the field of oil-water separation because of its low energy consumption. However, the practical applications of polyvinylidene fluoride (PVDF) microfiltration membrane are limited due to its strong hydrophobicity and poor anti-fouling. A superhydrophilic/underwater superoleophobic PVDF microfiltration membrane is prepared through surface co-coating inspired by mussel chemistry. The dopamine (DA) and fulvic acid (FA) generate a hydrophilic coating with hydrophilic functional groups through a mild Michael addition/Schiff base reaction. When the DA/FA ratio is 2/8 and a modification time is 6 h, the pure water flux reaches 8011 L m −2 h −1 bar −1 , the flux of oil-in-water emulsion is 1915 L m −2 h −1 bar −1 , and the rejection is 99.1 %. The retention rate of the membrane for oil-water emulsions containing different oil phases (heavy and light oils) is consistently above 98.5 % and shows high recoveries ( FRR > 86.6 %) after twenty separations. Modified membranes have high anti-pollution ability for characteristic pollutants in water bodies (for example: BSA, SDS). This work demonstrates a simple surface coating preparation method that has excellent separation performance, and environmental friendliness, offering a promising strategy for large-scale modified membranes to treat oily wastewater.
研究领域:
材料科学
·
环境工程
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2011
·
IF 1.795
Jing Yuan,Jian-qiang Meng,Yin-lin Kang,Qi-yun Du,Yu-feng Zhang
This paper describes a facile and novel approach for the surface glycosylation of poly(vinylidene difluoride) (PVDF) microporous membrane. A glycopolymer poly( d -gluconamidoethyl methacrylate) (PGAMA) was tethered onto the membrane surface via activators generated by electron transfer atom transfer radical polymerization (AGET ATRP) directly initiated from the PVDF surface. Chemical changes of membrane surface were characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). It was revealed that PGAMA was successfully grafted onto the membrane surface and its grafting density can be modulated in a wide range up to 2.4 μmol/cm 2 . The effects of glycosylation on membrane morphology, flux and surface hydrophilicity were investigated. Field emission scanning electron microscopy (FESEM) results indicated shrinkage of the surface pore diameters and the growth of the glycopolymer layer on the membrane surface. The static water contact angle (WCA) of the membrane surface decreased from 110° to 30.4° with the increase of grafting density, indicating that the PGAMA grafts dramatically improved the surface hydrophilicity. The protein adsorption and platelets adhesion experiments indicated that the grafted PGAMA could effectively improve the membrane antifouling property and biocompatibility.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2020
·
IF 5.774
Rehan Khan,Ihtisham Ul Haq,Heng Mao,Ao-Shuai Zhang,Li-Hao Xu,Hong-Gang Zhen,Zhi-Ping Zhao
Phenol is highly toxic and carcinogenic even at low concentrations. This study focused on preparing high-performance mixed matrix membranes (MMMs) for the pervaporation separation of phenol from its aqueous solution. A highly-efficient zeolitic metal azolate framework, RHO-[Zn(Heim) 2 ] (MAF-6, Heim = 2-ethylimidazole) was incorporated into the polyether block amide (PEBA-2533) supported on the polyvinylidene fluoride (PVDF) ultrafiltration membrane. The MAF-6 was chosen as the filler due to its inherent hydrophobic surfaces and aperture size (7.6 Å), which is larger than the molecular kinetic diameter of phenol (6.6 Å). Effects of the casting solution concentration, active layer thickness, MAF-6 loading, operating temperature, and phenol concentration were systematically investigated. With the increase of the MAF-6 loading ratio X from 0 to 7, the phenol flux of the membrane was gradually enhanced, but the water flux was reduced. For 1000 ppm phenol aqueous solution at 80 °C, MAF-6–7@MMM displayed the optimal separation factor of 25.9 with a phenol flux of 89.2 g∙m −2 ∙h −1 . The pervaporation separation index (PSI) of the MAF-6–7@MMM was 1317.7 kg∙µm∙m −2 ∙h −1 at 80 °C, which was much higher than the PEBA/PVDF membrane (787 kg∙µm∙m −2 ∙h −1 ). Impressively, an increasing feed temperature enhanced the phenol flux more prominently than water, owing to the hydrophobicity and porosity of MAF-6. Consequently, the resultant MAF-6-X@MMMs broke the trade-off limitation between phenol permeability and selectivity. The as-prepared membrane also exhibited exceptional long-term stability, suggesting its prospect of industrial application.
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
RSC Advances
·
2024
·Vol. 14
·期 26
·18432-18443
·
IF 3.9
Jiao Wang,Hemu Pi,Panchao Zhao,Na Zhou
The presence of methyl orange (MO) and ciprofloxacin (CIP) in wastewater poses a serious threat to the environment and human health. Titanium dioxide nanoparticles (TiO2 NPs) are widely studied as photocatalysts for wastewater treatment. However, TiO2 NPs have the drawbacks of high energy required for activation, fast electron–hole pair recombination and difficulty in recovering from water. To overcome these problems, europium decorated titanium dioxide/poly(vinylidene fluoride) (Eu–TiO2/PVDF) membranes were successful prepared in this work by combining the modified sol–gel method and the immersion phase inversion method. The Eu–TiO2/PVDF membranes obtained with the increase of Eu–TiO2 NPs content during the preparation process were named M1, M2 and M3, respectively. The pure PVDF membrane without the addition of Eu–TiO2 NPs was named M0, which was prepared by the immersion phase inversion method and served as a reference. The prepared Eu–TiO2/PVDF membranes could not only adsorb MO, but also degrade CIP under visible-light irradiation. Moreover, the Eu–TiO2/PVDF membranes exhibited adsorption–photocatalytic activity towards a mixture of MO and CIP under visible-light irradiation. Last but not the least, the Eu–TiO2/PVDF membranes exhibited excellent recyclability and reusability, opening the avenue for a possible use of these membranes in sewage-treatment plants.
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
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Jingtong Yu,De Sun,Dongmin Yue,Bingbing Li,Tie Zhu,Peixiang Liu
One of the most promising desalination techniques is photothermal membrane distillation (PhMD). The research focus of PhMD technology is material renewal and structural design. Herein, the CuMOF-PVDF photothermal membranes were designed for PhMD. Firstly, a combination of chemical plating and oxidation was used to generate Cu(OH) 2 nanowires (NWs) onto the PVDF membrane. Then, the ligands were chemically bonded with Cu(OH) 2 NWs to grow the photothermal layer formed by the CuMOF hierarchical structure (CMHS). Under sunlight irradiation, the light was trapped in the CMHS, amplifying absorption and conversion of light. The CuMOF-PVDF membrane with the match-like CMHS absorbed 88.6 % of the light, resulting in a surface temperature of 74.3 °C after 600s. Moreover, by reducing the evaporation enthalpy of water, the performance of the CuMOF photothermal layer was comprehensively improved, realizing a water evaporation rate of 1.55 kg‧m −2 ‧h −1 and a high photothermal conversion rate of 71.4 %. During the PVMD process, the feed solution in the CuMOF photothermal layer was fully heated and supplied to the vaporization area, weakening the temperature polarization. Consequently, the flux of the CuMOF-PVDF membrane was 3.07 kg‧m −2 ‧h −1 and a 99.9 % rejection rate, corresponding to an energy efficiency of 85.2 %. The CuMOF-PVDF membrane is an efficient tool for PhMD, helping to advance desalination technologies.
研究领域:
材料科学
·
环境工程
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子