Journal of Environmental Chemical Engineering
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2021
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IF 5.909
Wanying Xie,Ji Li,Feiyun Sun,Wenyi Dong,Zijun Dong
Aiming at the fouling problem of PVDF membrane, one novel integrated strategy was used for the first time, including hydrophilic membrane modification and low-pressure operation. Permeability and anti-fouling ability of PVDF were simultaneously improved by nano-TiO 2 embedment. From perspective of operating condition optimization, the concepts of critical flux (J C ) and threshold flux (J TH ) were recommended as fouling-control tools. The J C and J TH of PVDF-TiO 2 membrane were tested by two constant pressure-steps methods, i.e. Constant pressure-step method and Alternating constant pressure-step method. Three indicators, consisting of instant FTTT curves, dFlux/dt condition and TMP-Flux ave curve, were employed to evaluate the J C and J TH of PVDF-TiO 2 membrane. In brief, the J C and J TH of PVDF-TiO 2 were 10.62 and 23.91 L/(m 2 ·h), respectively, which were nearly 3 times of PVDF membrane. Fouling resistance results displayed that protein irreversible fouling of two PVDF membranes were effectively reduced by J C mode and J TH mode. Besides, reversible fouling of PVDF-TiO 2 membrane was controlled well by J C mode meanwhile. The pure water filtration line (PWF line) and the normalized resistance were both used to judge the form of J C of two membranes. As compared with PVDF, it was speculated the enhancement of J C and J TH mainly related to the better hydrophilicity and local hydraulic condition of PVDF-TiO 2 modified membrane.
研究领域:
环境科学
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材料科学
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生物工程
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DOI
高影响因子
Membranes
·
2024
·Vol. 14
·期 11
·241
·
IF 3.3
Wenbin Sun,Longbo Xia,Ping Luo,Dong Zou
Polyvinylidene fluoride (PVDF) membranes are extensively utilized in membrane distillation (MD) for water treatment. However, traditional methods easily form asymmetrical membranes with dense skin layers that are detrimental to membrane flux. Herein, an eco-friendly PVDF membrane was fabricated by utilizing a delayed phase separation process without using any pore-forming agents. In addition, methyl-5-(dimethylamino)-2-methyl-5-oxopentanoate (PolarClean) was used as a green solvent without posing risks to humans and the environment. It was demonstrated that the PVDF concentration is crucial in influencing the microstructures and performance of the resulting membranes. As the PVDF concentration increased, the morphology changed significantly, resulting in a reduction of pore size. When feeding the device with NaCl solution at a concentration of 35 g/L, the MD water vapor flux reached 18.49 kg·m −2 ·h −1 , while maintaining a salt rejection of over 99.97% during the continuous operation for 24 h. This work presented a method for producing green PVDF membranes via delayed phase inversion with satisfactory water vapor flux and salt rejection, highlighting their prospect for effective applications in MD for water treatment.
研究领域:
材料科学
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环境工程
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DOI
PubMed
高影响因子
Journal of Water Process Engineering
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2021
·
IF 5.485
Zixin Wu,Jiaying Tian,Lili Wu,Chaocan Zhang
Membrane technology plays an important role in wastewater separation and purification. However, the problem of poor hydrophobicity of the membrane is a serious obstacle to its application. With anti-cancer, prevention and control of cardiovascular diseases and other effects, tea polyphenols (TP), the main component of tea stains, have been widely studied in medical treatment, food, and biology. Here, inspired by an interesting phenomenon that some tea stains are difficult to clean in the cup after brewing tea, a facile tea polyphenols coating method was explored at the ambient condition to mitigate membrane fouling . The modification method is not only environmental protection, low cost, but also safe and healthy. The contact Angle of the TP modified film is reduced to 39°, and the pure water flux is up to 13,159 L•m-2• H-1, indicating that the hydrophilicity is significantly improved. In addition, TP film also has excellent antifouling performance (emulsion retention rate is 98.9%, water flux recovery is about 99.7%). Meanwhile, the TP modified membrane was stable in the acidic condition in the long-term rinsing experiment. In addition, titanium ions were introduced to improve the stability of TP-modified membranes under pure water or alkaline conditions since the TP coating imparts a binding side to bind metal ions . In the pure water and alkaline condition, the modified membrane showed outstanding stability after Titanium ions have been complexed.
研究领域:
膜技术
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材料科学
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环境工程
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DOI
高影响因子
Journal of Environmental Chemical Engineering
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2023
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IF 7.7
Shusu Shen,Honglin Li,Yang Shen,Renbi Bai,Ganwei Zhang
Metal organic frameworks (MOFs) possess excellent post-modification characteristics, high specific surface area, diversity of skeleton composition and pore tunability, have been increasingly applied in membrane modifications. In this work, NH 2 -MIL-88B(Fe) (NM88B) was first fixed onto polyvinylidene fluoride (PVDF) membrane by polyethyleneimine (PEI) through a vacuum-assisted self-assembly process, and the deposited NM88B was subsequently grafted with perfluoroalkyl polyethoxyacetic acid (FPEOAA) via a condensation reaction to realize the surface modifications. The modified membranes (named as N1F x ) showed improved hydrophilicity and underwater-oleophobicity. In addition, very high pure water flux (up to 9403 L‧m −2 ‧h −1 ) was obtained for the N1F x membranes due to the high porosity of introduced NM88B. In the dead-end filtration experiments of n -hexadecane-water emulsion, the optimum membrane N1F20 showed a good oil rejection rate (98.3%) and high permeation flux (667 L‧m −2 ‧h −1 ) which is approximately seven times of the pure PVDF membrane, indicating that the surface-modified membranes had excellent permeability and good separation performance. Even after four filtration cycles of oil-water emulsion, the rejection rate maintained higher than 97%, showing good reusability. Furthermore, the study found that N1F20 had certain acid and alkaline resistance and great potential for engineering applications.
研究领域:
材料科学
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环境工程
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Qian Wang,Xue Zhu,Xinglin Li,Lin Chen,Hengyang Mao,Xiaoshan Meng,Taoli Huhe,Zhengzhong Zhou
Membrane separation technology with high separation efficiency and low energy consumption are one of the keys to tackle the water-energy crisis. However, membrane fouling can reduce membrane life and performance, limiting its application. In this work, hydrophilic modifier sodium lignosulphonate (SLS) and antibacterial agent CuCl 2 were adopted as additives to modify PVDF membranes. The addition of SLS can optimize the structure of PVDF membranes and increase hydrophilicity, enhancing separation and anti-fouling performance. Moreover, the SLS can fix Cu 2+ effectively onto the membrane for improved antibacterial performance, as the leakage of Cu 2+ is reduced greatly, compared to Cu-PVDF membranes without SLS. The simulation based on density functional theory proved that the binding energy of SLS and Cu 2+ is 2.7 times of that of PVDF and Cu 2+ . Finally, the prepared anti-fouling Cu-SLS/PVDF membrane was applied in the separation of simulated Escherichia coli fermentation broth, exhibiting long-term antibacterial and anti-fouling property. This work provides a new idea for the preparation of long-term anti-fouling and antibacterial membrane, and has good potential in the recovery of fermentation broth.
研究领域:
环境科学
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材料科学
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生物学
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产品关联
DOI
高影响因子
LANGMUIR
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2025
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IF 3.9
Yiming Wu,Jing Yang,Ruifeng Zhang,Hongji Li,Ruihua Mu,Yamei Zhao
Polyvinylidene fluoride (PVDF) membranes represent a potential technology for the in-depth treatment of organic dye-containing wastewater. Nevertheless, the intractable membrane fouling and the limited versatility have significantly constrained its applications. Herein, through the nonsolvent-induced phase inversion method, we have successfully fabricated the PDA@MgO/PVDF and PDA@ZnO/PVDF membranes, which are modified by the synergistic action of MgO or ZnO nanoparticles with polydopamine (PDA), respectively. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), as well as the analyses of pore structure, contact angle, and surface free energy, were utilized to characterize the hybrid membranes. The results demonstrate that the modification of PDA@MgO and PDA@ZnO can enhance the hydrophilicity, pure flux, dye rejection, and pollution resistance of PVDF membranes. The enhanced hydrophilicity of the modified membranes results from the increase in surface free energy and its polar component term. Comparatively, the PDA@ZnO/PVDF membrane exhibits a smaller contact angle (69°) and a higher pure water flux (378.63 L/m2·h·bar), whereas the PDA@MgO/PVDF membrane possesses greater mechanical strength and better antifouling performance. The PDA@MgO/PVDF membrane can achieve a rejection rate of 94.6% for disperse deep blue 79, and the flux recovery rate can reach approximately 82%. This research offers novel insights into the application of PVDF membranes for the treatment of organic dye-containing wastewater.
研究领域:
材料科学
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环境工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
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2024
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IF 5.9
Shixiong Chen,Jiarong Wang,Jing Zhang,Qinghao Zeng,Hong Jiang,Haiqing Chang,Tian C. Zhang,Xiaobao Tian,Kai Wang,Ying Liang
Surface modification could remarkably improve the oil–water separation ability of membrane, but suffers from limited survival positive effect layer after long-term operation. Herein, we report a systematic comparative study between bulk and surface modification (i.e., synchronous or sequential electrospun/elecrospraying) on hydrophobic polyvinylidene difluoride (PVDF) membrane. A hydrophilic UiO-66-NH 2 @polyacrylic acid micro/nanospheres (UiO@PAA) was selected as functional layer to improve the separation and adsorption capability of PVDF. The surface modification (SMM) and bulk modification membranes (BMM) exhibited the similar water wetting behavior in air as the same surface layer. The spider filament-like nanofibers of BMM could enhance the mechanical stability and dispersion uniformity of active sites among the PVDF fibers. In terms of oil-in-water emulsions separation ability, the BMM was superior to the SMM with the maximumly increase of separation efficiency and filtration flux to 1.3 % and 192.6 L m -2 h −1 , respectively. As for dye absorption, the BMM showed better adsorption capacity with a removal efficiency over 96 %. For the low concentration of methylene blue, the removal efficiency of SMM was only 94 %, while the removal efficiency of the BMM reached 98 % at room temperature. In addition, the BMM exhibited higher removal efficiency over 94 % compared with that less than 84 % of SMM after eight cycling tests, confirming its advantages in repeatability. This study demonstrates that the bulk modification can endow the initial membrane with better performance and durability, showing more promising prospects in actual wastewater treatment.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Desalination and Water Treatment
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2024
·
IF 1
Shuyi Chen,Noor Khatoon,Chen Zhang,Qi Zhang,Shuhong Jiang,Honghai Yang,Jun Wang
Selective recovery of recyclables is a major challenge when treating textile wastewater. For this reason, there is an urgent need to develop nanofiltration membranes with high permeability and selective filtration. In response, a novel composite PVDF loose nanofiltration membrane was developed by combining two different mixed amines system/dopamine (DA) followed by interfacial polymerization with benzoyl chloride (TMC). The two different amines systems were a mixture of GAZ and PEI and a mixture of PIP and PEI, respectively. The effects of GAZ/PEI and PIP/PEI on the microstructure was characterized by SEM, AFM, FTIR and XPS and performance of the membrane was also investigated. The effects of GAZ/PEI and PIP/PEI on the microstructure and the selective layer of membranes were different. The results stated that with the increase of GAZ/PEI the thickness of the selective layer, surface roughness decreased, while the fluxes of pure water and dye wastewater increased. However, with increasing PIP/PEI, surface nodules and roughness both increased. Contrarily, the thickness of the selective layer and PEG800 rejection first decreased and then increased, while the flux of pure water and the dye wastewater first increased and then decreased. The optimal GAZ/PEI and PIP/PEI were 9/91 and 50/50, respectively. When the GAZ/PEI was 9/91, the pure water flux and the RB5 wastewater flux were 20.7 L∙(m 2 ∙h) −1 and 11.5 L∙(m 2 ∙h) −1 . The dye (RB5) retention rate was 94.3% and salt retention rate was 2.1%. However, when the PIP/PEI was 50/50, the pure water flux and RB5 wastewater flux were 26.6 L∙(m 2 ∙h) −1 and 17.1 L∙(m 2 ∙h) −1 increased by 87.3% and 134.2% respectively. The retention rates of RB5 and NaCl were 96.3% and 1.7%. The above results indicate that the composite PVDF LNF membranes prepared with mixed amine monomers instead of single amine monomers have good selective filtration performance.
研究领域:
材料科学
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环境工程
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2020
·
IF 3.99
Rui Zhang,Yu Li,Youfeng Cai,Qiong Han,Tongqing Zhang,Yi Liu,Kunling Zeng,Chen Zhao
Silver-phosphate/graphene oxide/APTES (Ag 3 PO 4 /GO/APTES) composite materials modified by 3-aminopropyltriethoxysilane (APTES) were incorporated into polyvinylidene fluoride (PVDF) membrane to obtain light catalytic membrane. The structure and morphology of Ag 3 PO 4 /GO/APTES were characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and thermogravimetric analyzer (TGA). Next, the morphology structure and roughness of Ag 3 PO 4 /GO/APTES/PVDF membrane were studied using SEM and Atomic force microscopy (AFM). The hydrophilicity and water flux of blended membranes were enhanced by the presence of a large number of hydrophilic groups on the surfaces of GO and APTES. Using Bovine serum albumin (BSA) solution as a pollution model, the multi-cycle anti-organic pollution ability of composite membranes was explored, and the anti-pollution performance was improved. The results showed that with the increase of Ag 3 PO 4 /GO/APTES content in the composite membrane, the rejection rate of dyes increases significantly. The enhanced photocatalytic degradation can be attributed to the presence of RGO which facilitates electron mediation and shuttle. This work provide a method for the efficient removal of dyes from wastewater.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
·
2019
·Vol. 29
·期 5
·1625-1636
·
IF 1.637
Zhang Rui,Zhu Xuyang,Liu Yi,Cai Youfeng,Han Qiong,Zhang Tongqing,Li Yu
In this work, the versatile filler (HNTs) consisted of a halloysite nanotube as skeleton and intermediate magnetic nanoparticles coating poly(dopamine + 3-aminopropyltriethoxysilane) derivate layer were prepared. PVDF membranes were then manufactured by incorporating a series of ratios of HNTs. The Fourier-transform infrared (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and transmission electron microscope (TEM) results proved that the modified materials were successfully achieved. The morphologies of membranes were characterized by scanning electron microscope (SEM) and atom force microscope (AFM). Meanwhile the PVDF hybrid membranes exhibited a stronger hydrophilicity (contact angle is 53°), higher bovine serum albumin (BSA) rejection (99%) than pure membrane (87°and 54%), and hybrid membranes maintain a higher flux recovery rate (FRR) that attains 85.3% after two cycles. Besides, the composite membrane showed a good removal rate (97.2%) of methylene blue. According to above experimental parameters, the 6% (based on PVDF mass) HNTs composite membrane was defined as the experimental optimal selection, and it could provide a promising candidate for methylene blue solution separation.
研究领域:
材料科学
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环境工程
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纳米技术
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 48
·20999-21006
·
IF 3.288
Junda Wu,Atian Xie,Jin Yang,Jiangdong Dai,Chunxiang Li,Yongsheng Yan,Jiuyun Cui
In order to solve urgent environmental problems caused by oil spills, it is meaningful and necessary to develop novel materials or techniques for efficient oil/water separation. Here, a new polyvinylidene fluoride (PVDF)-based composite membrane was successfully fabricated via a layer-by-layer self-assembly process, where the active sites were provided by pDA for the CaCO3 growth. Importantly, the CaCO3 structure could be regulated by the concentration of the precursor solution, showing the high flexibility of preparation. The as-prepared PVDF@pDA@CaCO3 membrane possessed superhydrophilic/underwater superoleophobic property and superior anti-fouling ability. In addition, the optimal PVDF@pDA@CaCO3-2 membrane showed a high permeation flux only under gravity, and the separation efficiency was as high as 99%. With the merits of low-cost and great separation performance, the as-prepared PVDF@pDA@CaCO3 membrane exhibited great potential in practical industrial applications for highly efficient oil/water emulsion separation.
研究领域:
材料科学
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环境工程
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
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IF 8.4
Weiguo Kong,Longfei Zhang,Na Yang,Bin Jiang,Luhong Zhang,Yong Liu
Rational design of hydrophilic hierarchical structures on the membrane surface is a promising method to improve oil/water separation efficiency. However, oil droplets with intrinsic adhesion tend to accumulate on the membrane surface, which deteriorates membrane performance. In this study, tannic acid-Zn(II) complex was homogeneously anchored on the PVDF membrane surface and further in situ converted to ZIF-8 in the presence of 2-methylimidazole. Subsequently, Cu ion exchange was employed to transfer ZIF-8 layer to gerhardtite (Cu 2 (OH) 3 NO 3 ) with a hierarchical structure. Accordingly, the as-prepared PVDF/TA-gerhardtite membrane possessed attractive hydrophilicity and underwater superoleophobicity with oil contact angles above 150°, therefore achieving over 98 % oil rejection towards various surfactant stabilized oil-in-water emulsions. Moreover, self-cleaning properties can be realized by activating peroxymonosulfate, and 97 % of tetracycline hydrochloride, the target pollutant, was degraded within 30 min owing to the generation of sulfate radicals and hydroxyl radicals. Due to the attractive hydrophilicity and catalytic oxidation capacity of the gerhardtite hierarchical structure, degradation and bubble generation induced fouling recovery was accomplished after PMS cleaning, and the irreversible fouling decreased to 2.2 % after consecutive soybean oil fouling. Therefore, this work provides new insights into the construction of hierarchical structures on membrane surfaces and demonstrates their potential applications in oil/water separation and fouling mitigation.
研究领域:
材料科学
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环境工程
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）