JOURNAL OF APPLIED POLYMER SCIENCE
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2023
·Vol. 140
·期 37
·e54417
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IF 3
Mingjie Lin,Junmei Ma,Xuping Xue,Shiyang Li,Qingyi Wang,Zixuan Lv,Congjie Gao,Linxin Xue
Polyamide (PA) based thin film composite forward osmotic (TFC-FO) membranes were prepared through inter-facial polymerization (IP) processes on porous cellulose acetate (CA) substrates. A dual solvent modification process of adding DMF in the aqueous phase followed by activation with methanol was found to be able to simultaneously improve the permselectivity and anti-fouling capability of the modified membranes. On top of the acidic CA substrates, DMF could not only absorb the HCl formed in the IP processes, but also chemically bind with the PA matrix by reaction with MPD monomers, leading to formation of homogeneous thin and flat PA layers, while methanol activation further swelled the PA matrix, repaired defects and optimized water permeating channels. Using 1 M NaCl solution as the draw solution, the water flux of the CA/PA-DMF4-ME1 membrane was twice that of the pristine membrane, and 24% increase in J w /J s value from 182 to 225 L·mol −1 . Its J w /J s value could be further increased 10 times to 2000 L·mol −1 using 1 M Na 2 SO 4 solution as draw solution. RO tests for the CA/PA-DMF4-ME1 membranes showed 6-fold increase in water permeance, from 1.16 to 7.02 L·m −2 ·h −1 ·bar −1 , as well as increase in NaCl rejection from 94.8% to 97.7% from pristine membrane.
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
Membranes
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2023
·Vol. 13
·期 7
·688
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IF 4.2
Jingyi Liang,Hansheng Huang,Hao Zhang,Yanhui Wu,Yongbing Zhuang
To explore the application of forward osmosis (FO) technology in the organic solvent recovery field, we prepared a new solvent-resistant triple layer thin film composite (TFC) membrane on the PI (polyimide) substrate. The deep eutectic supramolecular polymers (DESPs) interlayer was constructed on the substrate to improve the separation performance and solvent resistance. DESPs interlayer was formed by mixing and heating with cyclodextrin as the hydrogen bond acceptor andL-malic acid as the hydrogen bond donor. The chemical changes, surface property and morphology of the composite membrane with DESPs interlayer were characterized. The separation performance and stability of the triple layer composite membrane in organic solvent FO were studied. For the monascorubrin-ethanol system, the permeation flux of TFC/DESPs5-PI membrane could reach 9.51 LMH while the rejection rate of monascorubrin was 98.4% (1.0 M LiCl/ethanol as draw solution), which was better than the pristine membrane. Therefore, this solvent-resistant triple layer composite FO membrane has good potential for the recovery of organic solvents.Keywords:organic solvent forward osmosis;composite membrane;interlayer;ethanol;monascorubrin
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
Frontiers in Nutrition
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2024
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IF 4
Wang Zilin,Tian Yang,Yang Min,Yang Junyan,Wang Yifan,Tao Liang,Sheng Jun,Shi Chongying
Background: In this study, deep eutectic solvents (DESs) combined with ultrasound-assisted extraction (UAE) were used to extract bioactive compounds from the leaves of Moringa oleifera Lam.Methods: The FT-IR method was used to analyze the structural characteristics of the DESs, and the extraction efficiencies of the DESs for total phenolic content (TPC) and total flavonoid content (TFC) were evaluated. The stability of the extracts under high temperature and UV radiation was assessed, and their antioxidant activity was investigated after undergoing in vitro simulated digestion.Results: The results show that the seven DESs extracted more TPC and TFC than did the 70% ethanol (36.27 ± 1.58 mg GAE/g, 23.09 ± 1.47 mg RT/g), and the extraction process of UAE-DES was optimized by selecting choline chloride: citric acid as the DES solvent, which has the highest extraction of TPC (86.92 ± 1.34 mg GAE/g) and TFC (49.73 ± 0.85 mg RT/g). The stability results indicated that the DES phenolic extracts were less stable when exposed to high temperature and UV radiation, indicating that DES extracts have better bioactivity. Moreover, after in vitro simulated digestion, the DES extract shows a higher DPPH free radical scavenging capacity (12.79 ± 3.88 mmol Trolox/g of DES extracts, 6.99 ± 4.02 mmol Trolox/g of ethanol extracts) and ferric ion reducing antioxidant power (62.61 ± 1.71 mmol Trolox/g of DES extracts, 55.07 ± 1.66 mmol Trolox/g of ethanol extracts) than ethanol extracts.Conclusion: This study confirmed that DESs are a new and environmentally friendly solvent that can be used for the extraction of phenolic compounds.
研究领域:
植物化学
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食品科学
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分析化学
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生物技术
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DOI
PubMed
高影响因子
Membranes
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2022
·Vol. 12
·期 4
·417
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IF 4.562
Mengling Zhang,Xiangyang Hu,Lei Peng,Shilin Zhou,Yong Zhou,Shijie Xie,Xiaoxiao Song,Congjie Gao
The realistic resistance zone of water and salt molecules to transport across a TFC-RO membrane is the topmost polyamide nanofilm. The existence of hollow voids in the fully aromatic polyamide (PA) film gives its surface ridge-and-valley morphologies, which confuses the comprehensions of the definition of the PA thickness. The hollow voids, however, neither participate in salt–water separation nor hinder water penetrating. In this paper, the influence of intrinsic thickness (single wall thickness) of the PA layer on water permeability was studied by adjusting the concentration of reacting monomers. It confirms that the true permeation resistance of water molecules originates from the intrinsic thickness portion of the membrane. The experimental results show that the water permeability constant decreases from 3.15 ± 0.02 to 2.74 ± 0.10 L·m−2·h−1·bar−1when the intrinsic thickness of the membrane increases by 9 nm. The defects on the film surface generate when the higher concentration of MPD is matched with the relatively low concentration of TMC. In addition, the role of MPD and TMC in the micro-structure of the PA membrane was discussed, which may provide a new way for the preparation of high permeability and high selectivity composite reverse osmosis membranes.
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
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2019
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IF 7.149
Shu Xiong,Sheng Xu,Anny Phommachanh,Ming Yi,Yan Wang
Polyamide TFC membranes are widely applied in membrane-based water treatment but generally suffer various fouling problems. In this work, the layer-by-layer assembly of phytic acid (PA) and metal ions (M) is constructed on the surface TFC membrane for the first time, to improve the bio/organic fouling resistances and separation performance of TFC membranes simultaneously. The PA molecule with six phosphonic acid groups of strong chelation ability acts as the organic ligand, and the metal ion acts as the inorganic cross-linker, inducing the assembly of hydrophilic and antibacterial PA-M (Ag or Cu) complexes on the TFC membrane surface. Various characterizations including FTIR, XPS, SEM, AFM, and EDX are employed to confirm the successful and uniform modification of PA-M. FO performance of the PA-M modified TFC membranes, i.e., TFC_PA-Ag and TFC_PA-Cu, is optimized by varying PA concentration and assembly cycles, where the water flux can be improved by 57% and 68%, respectively, without compromising the membrane selectivity. Additionally, the PA-M modification improves the biofouling and organic fouling resistances of the TFC membrane remarkably, owing to the enhanced antibacterial ability and hydrophilicity. The modified TFC membranes are also proven to show the excellent stability by the quantitative release test.
研究领域:
材料科学
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环境工程
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化学工程
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DOI
PubMed
高影响因子
DESALINATION
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2018
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IF 6.603
Guihua Xie,Wenxuan Xu,Qingchun Ge
Gradual ionizing forward osmosis (FO) membranes were synthesized through tailoring modifications with alendronate materials on polyamide thin film composite (TFC) membrane surfaces . The newly developed membranes have gradually ionized surfaces and are more hydrophilic after introducing amino, hydroxyl and phosphate groups derived from the alendronates. Significantly improved performance was achieved with the alendronate-modified membranes relative to the unmodified membrane. With DI water as the feed and 0.5 M MgCl 2 as the draw solution, the novel membranes yielded water fluxes 35–60% higher than the nascent one. When MgCl 2 (2.0 M) as the draw solution, alendronate tetrasodium (A-4Na) modified membrane had a water permeation rate of 17.3 LMH under FO mode (feed solution faced the membrane active layer) in seawater desalination , a 25% increase compared to that of the pristine membrane and surpasses many other recently-developed FO membranes, remarkably increasing water filtration efficiency.
研究领域:
化学工程
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环境科学
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材料科学
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水处理
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DOI
高影响因子
DESALINATION
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2017
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IF 5.527
Xinzhen Zhao,Jing Li,Changkun Liu
The physical and chemical characteristics of the porous supporting layer play a key role in the separation efficiency and concentration polarization of the forward osmosis (FO) membranes. In this paper, the modified polyvinylidene fluoride (PVDF) porous membranes with high porosity and large amounts of surface membrane pores were prepared with zinc oxide (ZnO) nanoparticles as the template, and used as the supporting layer of the FO membrane. The modified FO membranes showed enhanced water permeability and separation selectivity . The increased water flux was based on the increase of the effective membrane area , and the decreased τ/ε (tortuosity factor/porosity) value obviously alleviated the concentration polarization phenomenon based on the optimization of the flow channel. The etching of the porous microstructure could reduce the limit of the supporting layer on the separation performance of the FO membrane, and provide a simple method to improve the separation efficiency of the thin film composite (TFC)-type FO membranes.
研究领域:
膜科学
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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 MEMBRANE SCIENCE
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2021
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IF 8.742
Chengbao Geng,Pei Huang,Fangbo Zhao,Hongxing Dong,Hongyan Niu,Yue Zhou,Jun Shen,Jiaming Zhang
The weak interfacial force among the substrate with polyamide layer is always a non-ignorable issue for the traditional thin-film composite (TFC) membrane during actual operation. To solve this issue, herein, we have proposed an effective strategy, which is enhancing the long-term separation durability of the TFC membrane by fixing the polyamide layer on the substrate through covalent bonding. To start with, an amino-substituted polyethersulfone (PES-NH 2 ) was synthesized and blended with polyethersulfone (PES) to prepare a hydrophilic PES/PES-NH 2 substrate. Next, the amino group in the substrate could effectively react with a part of acyl chloride groups in the organic phase to form the stable covalent bond with the polyamide layer formed by interfacial polymerization. The prepared PES/PES-NH 2 TFC membrane possessed a denser polyamide layer with a higher cross-linking degree, as well as exhibited greatly increased separation performance at 0.6 MPa. Significantly, the PES/PES-NH 2 TFC membrane still maintained excellent separation performance under a long-term filtration period of 15 days, which is also much longer than the PES TFC membrane. This effective and promising method provides a valuable way to maintain the separation stability of TFC membrane in long-term operation.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2018
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IF 6.735
Langming Bai,Yatao Liu,An Ding,Nanqi Ren,Guibai Li,Heng Liang
In this study, cellulose nanocrystals (CNCs) were incorporated into a polyamide (PA) layer to prepare novel thin film composite (TFC) nanofiltration membranes (CNC-TFC-Ms). Scanning electron microscopy (SEM) results revealed differences in the surface morphologies of the CNC-TFC-Ms compared with that of a control membrane (TFC-control-M). The pore size distribution (PSD) results showed that the CNC-TFC-Ms exhibited smaller pore sizes and narrower PSD curves as the CNC content in the PA layer increased. Continuous potential measurements showed that the negativity of the surface charge of the CNC-TFC-Ms decreased as the CNC concentration increased. The CNC-TFC-Ms showed great rejection performance for divalent salts with rejection rates over 98.0% and 97.5% for Na 2 SO 4 and MgSO 4 , respectively. Meanwhile, the filtration flux of salts was dramatically enhanced compared with that of TFC-control-M. Additionally, the permeate flux and rejection of NaCl were simultaneously enhanced as the CNC content increased, demonstrating that CNC-TFC-Ms can overcome the trade-off limitation. In addition, the NaCl/Na 2 SO 4 selectivity of the CNC-TFC-Ms reached as high as 60, suggesting their distinguished divalent/monovalent separation characteristics. The CNC-TFC-Ms exhibited greater dye removal for both anionic and cationic dyes due to their decreased negative charge and smaller pore size than the control membrane.
研究领域:
材料科学
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环境工程
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膜技术
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Yue Zong,Ruijun Zhang,Shanshan Gao,Jiayu Tian
Reducing the thickness of the polyamide (PA) layer has been confirmed as a feasible strategy to improve the permeability of the thin film composite (TFC) nanofiltration (NF) membrane. In this study, a novel interfacial polymerization (IP) approach assisted by the volatilization of n-hexane was proposed to promote the formation of a thinner PA layer, in which a small amount of n-hexane was added onto the substrate membrane after aqueous phase immersion and before the organic phase coating, then the temperature of the substrate membrane together with the water-soluble monomer solution would be decreased due to the volatilization of n-hexane. The infrared thermographies demonstrated that 7.8 μL cm −2 n-hexane dosage was the most efficient, which can sharply decrease the surface temperature from room temperature (25 °C) to 7.9 °C. The TFC membranes prepared at the lower temperature presented much higher permeability. When PIP concentration was 0.3% w/v, TMC concentration was 0.1% w/v and IP reaction time was 40 s, the PA layer formed at this low temperature was smoother and more hydrophilic. Its thickness was reduced from 26.97 nm to 11.98 nm and water permeability was increased by 50% to 36.7 L m −2 h −1 bar −1 while maintaining Na 2 SO 4 rejection of 96.5%.
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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2022
·
IF 10.53
Xian Chang,Zixuan Lv,Hang Yu,Shiyang Li,Guojun Jiang,Congjie Gao,Lixin Xue
Thin Film Composite Polyamide (TFC-PA) Total Heat Exchange Membranes (THEMs) with ultrahigh sensible heat exchange efficiency, high enthalpy exchange efficiency, high CO 2 gas barrier property were successfully prepared by interfacial polymerization between m-phenylenediamine (MPD) and trimesoyl chloride (TMC). The performances of formed THEMs could be greatly impacted by their surface roughness , thickness, surface hydrophilicity, cross-linking degree and counter-ions retention controlled by the MPD concentration, TMC concentration, reaction time and post treatment procedures. Their H 2 O permeation coefficient could be improved by increasing the surface hydrophilicity and decreasing cross-linking degrees of the formed polyamide layers while their CO 2 barrier property could be improved by retaining more counter ions in PA layers. THEMs with ultrahigh sensible heat exchange efficiency of 95%+, high enthalpy exchange efficiency of 60%–65%, greatly improved CO 2 barrier property and superior mechanical strengths could be obtained for potential applications in ERV systems.
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
DESALINATION
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2022
·
IF 11.211
Xiumin Zhang,Yongping Dong,Qingyi Wang,Hang Yu,Congjie Gao,Lixin Xue
Structures and NF performance of TFC-Co and TFC membranes activated with 50 % alcohol solutions were studied. Methanol and glycol solution activation increased water flux 2–4 times without trading off salt rejection while glycerin solution activation increased water flux 3–4 times with reduced salt rejection and increased dye/salt retention selectivity . The Stokes radius of TFC-Co membrane changed from 0.77 nm to 0.66, 0.78 and 0.92 nm while the TFC membrane changed from 0.54 nm to 0.55, 0.65 and 0.70 nm after activation with methanol, glycol and glycerin solutions, respectively. Capillary pore filling models were developed from pure alcohol absorption experiments including the stages of initial pore filling, pore expansion, pore relaxation and pore adjustment, while most Stokes radius after 50 % solutions activation were found to be close to the relaxed pore radius values (r rx ) or half of the expanded pore radius values (r ex ) from pure alcohol absorption experiments.
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
危险品化学品经营许可证（带存储）