SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Guoying Feng,Runkai Su,Zhiguo Yan,Shaoping Li,Man Xu,Cunwen Wang,Yanbo Li
Nanofiltration membranes have been popularly used in water reclamation to remove trace organic compounds. Nanofiltration membranes with low molecular weight cut-off (MWCO) and lower salt rejections are preferred to apply in water reclamation to avoid scaling. In the present work, polyelectrolyte complex nanofiltration membranes with lower MWCO were fabricated by electrostatic deposition of branched PEI on hydrolyzed PAN support, following glycerol treatment and thermal annealing. The performance of the membranes was evaluated by removing pharmaceuticals. At optimal conditions, a PEI/PANH membrane with MWCO around 200 Da was prepared. The membrane had a slightly positively charged surface in a nearly neutral environment. The rejections to neural solutes, such as PEG 200 and triclosan, were up to ∼ 90 %, and the rejections to the salts (NaCl, CaCl 2 , and MgSO 4 ) were lower than 10 %, showing good organic selectivity toward salts. The crosslinking steps reversed the charge property of the membrane surface and narrowed the pores of the membrane. Consequently, both salt and organic rejections increased (higher than 80 % for the pharmaceuticals), and more increments were for salts. Incorporation of the cross-linker in the glycerol solution provided a facile method to crosslink the PEI/PAN membrane. These results demonstrate the feasibility of using the simple electrostatic deposition method to prepare low MWCO nanofiltration membranes for trace organic removals.
研究领域:
环境科学
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材料科学
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水处理技术
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2022
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IF 10.53
Ling Yu,Kuiling Li,Yong Zhang,Jun Wang,Guoliang Zhang
Development of acid resistant nanofiltration membranes (ARNFMs) with high metal rejection, high flux and low molecule weight cut-off (MWCO) remains a big challenge. The separation performance of polyamine ARNFM is partially limited by the dense structure caused by the high concentration of organic phase solution. Herein, in this work, a novel effective post-treatment of citric acid (CA) was utilized to further improve the separation property of dually charged polyamine ARNFMs with low MWCO. An appropriate CA post-treatment (1.5 mol/L, 30 min, 65 °C) could gently remove off the oligomers and CA molecules would react with the redundant protonated/non-protonated amino, imine and hydroxyl groups of the polyamine NFM. Therefore，after the post-treatment, the membrane flux was enhanced 7.1 times with a high MgCl 2 rejection (97.6%) and a low MWCO around 220 Da. Furthermore, CA post-treatment not only had no significant influence on the acid stability of this membrane, but would also protect the membrane from the drastic effect of HCl (hydrolyze -Cl into –OH) in turn. All the results indicated that CA post-treatment has positive effects on polyamine ARNFMs, and the resulted dually charged polyamine ARNFMs have a good application potential for acidic wastewater treatment .
研究领域:
环境科学
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化学工程
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材料科学
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2023
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IF 9.5
Runkai Su,Guoying Feng,Man Xu,Cunwen Wang,Yanbo Li
The present work provides an efficient strategy to prepare mussel-inspired nanofiltration membranes with lower MWCO, via combining the catechol-amine chemistry and the chemistry of amino-silane coupling agents. The membranes were synthesized by stepwise depositing tannic acid (TA) and pre-hydrolyzed 3-aminopropyltriethoxysilane (APTES) on the PSF support. TA adsorbed on the polysulfone (PSF) support via hydrogen bonding . The pre-hydrolyzed APTES self-polymerized and reacted with TA, forming a crosslinked network through the Michael addition/Schiff base reactions. The membrane performance was tailored by controlling the hydrolysis degree of APTES. At optimal conditions, the APTES-TA/PSF membrane with MWCO of 200 Da and water permeance of 11 Lm −2 h −1 bar −1 was fabricated. The salt rejections toward Na 2 SO 4 and NaCl were around 90% and 20% respectively. The continuous prolonged filtration showed the membrane had good filtration stability. Compared with previously reported mussel-inspired and polyphenol membranes, the present membrane had a much lower MWCO and higher permeance. The membrane can efficiently remove typical pharmaceuticals with molecular weight from 200 to 400 Da, indicating this type of membrane has promising prospects in trace-organic contaminated wastewater treatment .
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高影响因子
Membranes
·
2025
·Vol. 15
·期 8
·231
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IF 3.6
Zhuangzhuang Tian,Yun Yin,Jiandong Wang,Xiuling Ao,Daijun Liu,Yang Jin,Jun Li,Jianjun Chen
Nanofiltration (NF) is considered a competitive purification method for acidic stream treatments. However, conventional thin-film composite NF membranes degrade under acid exposures, limiting their applications in industrial acid treatment. For example, wet-process phosphoric acid contains impurities of multivalent metal ions, but NF membrane technologies for impurity removal under harsh conditions are still immature. In this work, we develop a novel strategy of acid-resistant nanofiltration membranes based on interfacial polymerization (IP) of polyethyleneimine (PEI) and cyanuric chloride (CC) with the s-triazine ring. The IP process was optimized by orthogonal experiments to obtain positively charged PEI-CC membranes with a molecular weight cut-off (MWCO) of 337 Da. We further applied it to the approximate industrial phosphoric acid purification condition. In the tests using a mixed solution containing 20 wt% P2O5, 2 g/L Fe3+, 2 g/L Al3+, and 2 g/L Mg2+at 0.7 MPa and 25 °C, the NF membrane achieved 56% rejection of Fe, Al, and Mg and over 97% permeation of phosphorus. In addition, the PEI-CC membrane exhibited excellent acid resistance in the 48 h dynamic acid permeation experiment. The simple fabrication procedure of PEI-CC membrane has excellent acid resistance and great potential for industrial applications.
研究领域:
材料科学
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膜技术
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环境工程
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化学工程
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纳滤
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耐酸性
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DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Runkai Su,Guoying Feng,Zhiguo Yan,Man Xu,Cunwen Wang,Yanbo Li
Mussel-inspired catechol amine chemistry has emerged as a novel strategy to fabricate nanofiltration (NF) membranes. However, the preparation takes hours, and the molecular weight cut-off (MWCO) of the resulting membranes is usually not low enough to reject small molecules. This work described a new method to prepare dense NF membranes using tannic acid (TA) and aminosilane coupling agent (KH792 (N-(2-aminoethyl)-3-aminopropyltrimethoxysilane)) as materials, with the assistance of ethanol-regulated oxidation. The NF membranes were made by stepwise depositing oxidized-TA and KH792 on PSF substrates. The oxidation of TA was regulated by adjusting the solvent composition or the dosage of NaIO 4 . The effect of NaIO 4 on the chemistry of TA was explored by various characterizations. The selective layer of an NF membrane, with a flux of 26.7 L·m −2 ·h −1 ·bar −1 and a MWCO of 200 Da, formed only within 10 min. The membrane had high rejections of naproxen, bezafibrate, and ibuprofen (>90 %), and the rejection of NaCl was lower than 20 %, exhibiting a good selectivity for antibiotics toward monovalent ions. Compared with literature-reported mussel-inspired membranes, the proposed method resulted in a membrane with much higher permeance and a lower MWCO, indicating the improvement and advantages among the Mussel-inspired methods for the synthesis of NF membranes.
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高影响因子
DESALINATION
·
2024
·
IF 8.3
Runkai Su,Guoying Feng,Man Xu,Cunwen Wang,Yanbo Li
Catechol-amine coatings offer versatile routes for surface modifications and nanofiltration (NF) membrane preparations. However, the formation of the selective layer is time-consuming and often deficient, rendering it unsuitable for large-scale applications. In this work, oxidation-induced self-polymerization and catechol-amine chemistry were combined to rapidly construct nanofiltration membranes in an aqueous medium . M -phenylenediamine (MPD) underwent oxidation and self-polymerized on a polysulfone (PSF) support. The addition of sodium periodate facilitated the subsequent tannic acid (TA) coating. The catechol-amine reaction between oxidized TA and poly-MPD forms crosslinked poly TA-MPD complexes, offering the resulting membrane a high selectivity. The role of NaIO 4 in the selective layer formation and the influences of the synthesis parameters on the membrane performance were discussed. Utilizing the facile method enabled the achievement of a low molecular weight cut-off (MWCO) NF membrane (180 Da). The membrane exhibited a high water permeance (10.9 Lm −2 h −1 bar −1 ) and good salt rejections (93 % for Na 2 SO 4 ). The filtration of the bovine serum acid (BSA) solution demonstrated the membrane has good antifouling performance with a flux recovery ratio (FRR) of 95.1 %. The proposed method offers a straightforward and rapid approach to fabricating low MWCO NF membranes in an aqueous medium, which has potential in large-scale applications.
研究领域:
材料科学
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化学工程
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环境科学
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高影响因子
REACTIVE & FUNCTIONAL POLYMERS
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2021
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IF 3.975
Qiang Li,Xiaotai Zhang,Lianwen Zhou,Chunhui Li,Na Zhang,Tingting Yan,Shicai Xu,Jihua Wang,Xinsheng Liu
The fabrication of a polyelectrolyte-based nanofiltration (NF) membrane with combined functions by a straightforward and scalable approach draws great attention. Herein, a polypeptide modified 1.5-bilayer polyelectrolyte NF membrane was fabricated by a novel brush assisted layer-by-layer (LBL) assembly technology using poly(allylamine hydrochloride) and poly(sodium-4-styrene sulfonate) as a polycation and a polyanion , and polylysine as a surface modifier. A denser separation layer can be formed by this approach compared to the classical static LBL assembly under the same assembled layer number. The membrane has an ultrathin separation layer (25 nm), and negatively charged surface in a neutral solution. It exhibits high rejections to potassium citrate (96.6%) and tetrasodium ethylenediamine tetraacetate (96.8%), and moderate rejection to sodium sulfate (85.3%). The molecular weight cut-off (MWCO) is 1360 Da. It also shows excellent antimicrobial property for the representative Gram-negative bacteria and fouling resistance to humic acid as foulant model. Moreover, chlorination treatment was firstly utilized to optimize the membrane structure and enhance the permeability from ca. 1.96 to 15.2 L/m 2 h bar, simultaneously keeping a high salt rejection. It was found that the chlorination process increases the negative charge density of the membrane surface and enlarges the free volumes between the polyelectrolyte chains.
研究领域:
材料科学
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化学工程
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环境科学
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生物技术
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DOI
高影响因子
DESALINATION
·
2014
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IF 3.96
Xiuzhen Wei,Songxue Wang,Yingying Shi,Hai Xiang,Jinyuan Chen,Baoku Zhu
A positively charged composite nanofiltration (NF) hollow fiber membrane was prepared by interfacial polymerization with polyethyleneimine (PEI) and trimesoyl chloride (TMC) as the reactive monomers . The preparation conditions were optimized, and a relatively simple preparation process was developed. In the optimized preparation process, Na 3 PO 4 is not needed and the heat-treatment process can be omitted, which saves operation time and reduces cost. The surface morphology and chemical structure of the resulting composite NF membrane were characterized by scanning electron microscopy (SEM), attenuated total reflectance-Fourier transform infrared (ATR-FTIR), and X-ray photoelectron spectroscopy (XPS). Pure water flux , contact angle, molecular weight cut-off (MWCO) and surface zeta potential of the composite NF membrane were also evaluated. The rejection of the NF membrane for MgCl 2 (1 g/L aqueous solution at 0.4 MPa) was above 97.0%, and the permeate flux was approximately 35.3 L/m 2 h. Furthermore, the NF membrane also showed excellent rejection performance for different dye molecules. The rejections of the NF membrane to brilliant blue KN-R, cationic red X-GTL, acid red B, rhodamine B and cationic gold yellow X-GL were 99.9%, 99.8%, 98.8%, 97.5% and 96.7%, respectively.
研究领域:
膜科学
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纳米技术
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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
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