PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
·
2022
·
IF 7.926
Cong Ma,Yaoyao Tian,Xinying Liu,Yajing Li,Pengda Zhang,Xiuru Chu,Liang Wang,Bin Zhao,Zhaohui Zhang
To address the internal concentration polarization (ICP) effect and membrane fouling problems of forward osmosis technology in pressure retarded osmosis (PRO) mode, another highly selective polyamide (PA) layer was introduced on the other side of the single-skinned forward osmosis (FO) membrane. Recently, a new symmetrical nanofiber support layer has shown excellent performance. For better proof, the nanofiber support layer and the phase inversion support layer were prepared separately in this study, respectively, and two double-skinned FO membranes were obtained via interfacial polymerization . By comparing various surface physicochemical properties of the nanofiber support layer and the phase inversion support layer, it can be seen that the double-skinned PA layer formed on the surface of the nanofiber support layer had better performance. The nanofiber double-skinned FO membrane showed water flux of 19.99 LMH when using 2 M NaCl and DI water as the draw and feed solution, much higher than that of the phase inversion double-skinned FO membrane. Furthermore, the anti-fouling performance of the nanofiber double-skinned FO membrane was also better than that of the phase inversion double-skinned FO membrane. This study pointed out a new direction for a double-skinned FO membrane with high permeability selectivity and provided a promising method for anti-membrane fouling.
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
JOURNAL OF MEMBRANE SCIENCE
·
2018
·
IF 6.578
Mengqi Shi,Zhi Wang,Song Zhao,Jixiao Wang,Peng Zhang,Xingzhong Cao
We report a novel pathway for preparing polyamide (PA) thin-film composite (TFC) reverse osmosis (RO) membrane with high permselectivity by incorporating tannic acid (TA) into the polysulfone (PSf) support. The support and RO membrane were characterized systematically. The results showed that (1) the support surface was enriched with TA due to the high hydrophilcity of TA and (2) TA endowed the RO membrane with a thinner and more compact PA active layer. The influencing mechanism of TA on the PA layer formation was discussed. TA affected the formation of PA layer through changing the m-phenylenediamine (MPD) molecules absorption behavior and the formation of the nascent film. The RO membrane desalination performances for both brackish water and seawater were evaluated. Due to the thinner and more compact PA active layer, PSf/TA-RO (the membrane prepared on PSf/TA support) possessed a higher rejection and a comparative flux compared to PSf-RO (the membrane prepared on PSf support). This work provides an effective way for preparing high performance RO membranes via utilizing support to tailor the aqueous phase monomer absorption and the formation of the nascent film.
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
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Weiya Zhu,Yang Liu,Kang Guan,Cheng Peng,Jianqing Wu
The support flux was first investigated as a separate influencing factor for its effect on performances of ceramic filtration membranes. Three pre-membranes were prepared by tape-casting and then transfer-coated to supports to form dual-layer ceramic membranes after sintering. Experiments demonstrated that membrane layers with almost the same properties were obtained despite the huge difference in support flux. When the support flux increases from 3.120 to 97.53 m 3 m −2 h −1 , the flux of these three membrane series have increased by 75%, 186% and 228%, respectively. Experimental rules can provide structural design and evaluation from the perspective of permeability. The limit membrane flux of a certain system was derived according to the resistance distribution law of internal membrane structure and the Darcy's theorem. On this basis, a method for designing support flux was proposed. Furthermore, we present a criterion to quickly and easily evaluate the match between the support and the top layer, which is the ratio of membrane resistance to total resistance. Finally, the filtration resistance of penetration caused by suction of membrane particles into the support was measured for the first time, taking the advantage of the transfer-coating method that inherently free of penetration. Our works are expected to deepen the understanding of the ceramic membrane structure and provided guidance for its rational design and optimization.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2018
·
IF 6.578
Jiantao Wang,Ruizhang Xu,Feng Yang,Jian Kang,Ya Cao,Ming Xiang
In this work, the influences of polysulfone (PSf) support layer on the morphology of polyamide (PA) selective layer was investigated. Interfacial polymerization was conducted on PSf support layers with different surface pore size or at the bulk interface. The bottom surface of PA layer was exposed by carefully dripping N , N -dimethylformamide onto the back side of thin film composite membranes . Morphological study showed that the porous structure of the bottom surface of PA layer was always accompanied by PSf layer with small surface pores. Conversely, when synthesized on PSf layer with large surface pores or at the bulk interface, this porous structure turned into featureless flat areas. In addition, the top side ridge-and-valley structure was also found to be linked to the porous structure on the bottom side. Based on the observations, a “nascent particles aggregation” model was proposed. By investigating how the morphology of PA layer was swayed by PSf layer, better understanding regarding the correlation between membrane performance and support layer properties could be obtained.
研究领域:
材料科学
·
膜技术
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Yatao Liu,Heng Liang,Langming Bai,Jiaxuan Yang,Xuewu Zhu,Xinsheng Luo,Guibai Li
A fundamental understanding of the correlation between membrane support characteristics and nanofiltration (NF) membrane performance is of great significance for further development of membranes for water treatment. This work investigated the effect of the support layer on the separation performance and stability of NF membrane and elucidated the mechanism by the Donnan-Steric Pore Model with dielectric exclusion (DSPM-DE) model. The properties of the support were regulated using nanomaterials , and the NF membrane prepared by interfacial polymerization on it was called the SM-C-NF membrane. The rejection ratios of the SM-C-NF membrane for artificial seawater and four dyes improved by 0.3%–20.7% compared with the pristine membrane (SM-0-NF). DSPM-DE modeling results demonstrated that the difference in the support layer varied the membrane parameters of the NF membrane, which were quantitatively related to the separation performance of the NF membrane. The changes in NF membrane parameters were attributed to the morphology and physicochemical properties of the support affecting the formation of the polyamide separating layer. Surprisingly, the variation of electrical parameters of the NF membrane induced by the support was the key factor for the membrane separation performance. The enhanced chemical and structural stability of the SM-C-NF membrane were ascribed to the robust polyamide layer formed by the support with large pore size and hydrophilic and rough surfaces. Taken together, our findings underscore the importance and great potential of the support layer in regulating the performance of NF membrane, which is conducive to broadening the perspective on the design of high-performance membranes.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Ruizhang Xu,Feng Gao,Yunqi Wu,Lei Ding,Dandan Chen,Tianyu Liu,Yansong Yu,Weiling Zhuo,Zhouyun Chen,Yunchu Zhang,Yiying Sun,Feng Yang,Jinyao Chen,Ya Cao,Jian Kang,Zhuo Zheng,Ming Xiang
The surface pore size and structure, as well as the hydrophilicity/hydrophobicity characterization of support layer are vital factors that affect the formation process of polyamide selective layer via interfacial polymerization. In this research, polysulfone support layers with similar pore structures but different hydrophilicity were prepared. Interfacial polymerization was conducted on the resulting support layers subsequently. As a single variable, how the support layer hydrophilicity affects morphology and performances of polyamide composite membrane were investigated. The results showed that: (1) if the surface pore sizes of support layers are similar, hydrophilic one could boost the diffusion rate of aqueous monomer into organic phase, and further affect the interfacial polymerization process; (2) hydrophilic support layer is not in favor of manufacturing polyamide composite membrane with good filtration performances and adhesion property; (3) hydrophilic support layer could not induce the polyamide formed within the support layer pore while the key factor is the interfacial position of aqueous phase and organic phase.
研究领域:
材料科学
·
膜技术
✓ 已验证
产品关联
DOI
高影响因子
Desalination and Water Treatment
·
2015
·
IF 1.173
Yangbo Huang,Haiyang Jin,Ping Yu,Yunbai Luo
In this study, polyamide thin-film nanocomposite (TFN) membranes were prepared on nanosilica-modified polysulfone (PSf) support layers for forward osmosis (FO) applications. Different contents of SiO2 nanoparticles (1, 3, and 5 wt%) were added to a dope solution to develop FO membranes with improved performance. The effects of SiO2 on the membranes were investigated by attenuated total reflectance-Fourier transform infrared spectrometry, scanning electron microscope, hydrophilicity measurement, and mechanical property tests. The results showed that the wettability of PSf substrates was improved with increasing concentrations of SiO2. The resulting TFN membranes had smaller structural parameters, which meant lower internal concentration polarization effects compared to typical thin-film composite membranes. However, SiO2 nanoparticle is a good modifying agent to enhance water permeability, but it could not improve the selectivity of TFN membranes. The FO performance was evaluated using deionized water as feed solution and either 1 or 2 M NaCl as draw solution in both membrane orientations. The FO water flux of the fabricated membranes increased from 9.1 to 22.3 LMH when the active layer faced the feed solution (AL-FS) and 18.2 to 41.9 LMH when the active layer was placed towards the draw solution (AL-DS), mainly due to the improvement of PSf substrate with an addition of SiO2.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
DESALINATION
·
2014
·
IF 3.96
Yuanna Sun,Lixin Xue,Yaojian Zhang,Xiulan Zhao,Yan Huang,Xudong Du
High water flux polyamide thin film composite (TFC) forward osmosis (FO) membranes with porous supporting substrate layers made from polysulfone (PSf) and polyethersulfone (PES) blends of varied PSf/PES ratio were prepared. The impact of PSf/PES ratio on the porous structure of the supporting substrates and resulting properties of TFC-FO membranes formed were investigated. There were three distinguished sections observed in the cross-sections of the substrates, a top dense skin section, a central porous section, and a bottom open section according to SEM images. With the joint favoring effects from maximum open bottom section percentage in the cross-section and maximum surface roughness , membrane samples made from substrates with a PSf/PES ratio of 2/3 exhibit a highest water flux of 27.6 L/m 2 h for 2 M NaCl draw solution from a de-ionized water feed solution. And their water flux reached 12.7 L/m 2 h under PRO mode and 10.6 L/m 2 h under FO mode from an ocean seawater feed solution containing 3.5 wt.% of NaCl. This high flux is related to the existence of heavily populated cone shaped protrusions observed on the surfaces of formed TFC-FO membranes, resulting from amplification in initial surface roughness of the porous substrate during the active layer forming interfacial co-polymerization process.
研究领域:
材料科学
·
环境工程
·
膜技术
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2021
·Vol. 11
·期 10
·2470
·
IF 5.076
Yingfu Lian,Gang Zhang,Xiaojun Wang,Jie Yang
Our current study experimentally evaluates the impacts of surface hydrophilicity of supports on the properties of polyamide (PA) thin-film composite (TFC) nanofiltration (NF) membranes. A series of “carboxylated polyethersulfone” (CPES) copolymers with an increasing “molar ratio” (MR) of carboxyl units were used to prepare supports with diverse surface hydrophilicities by the classical nonsolvent-induced phase separation (NIPS) method. Then, the PA-TFC NF membranes were finely fabricated atop these supports by conventional interfacial polymerization (IP) reactions. The linkages between the surface hydrophilicity of the supports and the characteristics of the interfacially polymerized PA layers as well as the permselectivity of NF membranes were investigated systematically. The morphological details of the NF membranes indicate that the growth of PA layers can be adjusted through increasing the surface hydrophilicity of the supports. Moreover, the separation results reveal that the NF membrane fabricated on the relatively hydrophobic support exhibits lower permeability (7.04 L·m−2·h−1·bar−1) and higher selectivity (89.94%) than those of the ones prepared on the hydrophilic supports (14.64~18.99 L·m−2·h−1·bar−1and 66.98~73.48%). A three-stage conceptual scenario is proposed to illustrate the formation mechanism of the PA layer in NF membranes, which is due to the variation of surface hydrophilicity of the supports. The overall findings specify how the surface hydrophilicity of the supports influences the formation of PA layers, which ultimately defines the separation performances of the corresponding NF membranes.Keywords:carboxylated PES copolymer;support effect;interfacial polymerization;selective PA layer;TFC nanofiltration membrane
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Hongshan Wang,Guangyong Zeng,Zhaomei Yang,Xi Chen,Ludan Wang,Yuan Xiang,Xiangdong Zeng,Zhenhua Feng,Binbin Tang,Xudong Yu,Ying Zeng
With the consumption of lithium resources increasing year by year, the investigation of high-performance salt lake lithium extraction technology is extremely important. In order to effectively separate Mg 2+ and Li + from brine, a novel charge-positive nanofiltration (NF) membrane with high permeability and excellent Mg 2+ /Li + separation factor was designed by interfacial polymerization (IP) in this work. A B15C5-MX-NF membrane was fabricated by blending hydrophilic two-dimensional (2D) MXene nanosheets into a PES membrane substrate to enhance the permeability, followed by the modification of polyamide (PA) layer with a crown ether molecule (Benzo-15-crown-5) to optimize the surface properties of membrane. The PA layer thickness was effectively reduced (58 nm) due to the enhancement in the interaction between the substrate membrane and PEI by the incorporation of MXene, while the addition of B15C5 provided additional Li + permeation channels. The B15C5-MX-NF membrane exhibited excellent permeability (16.1 L·m −2 ·h −1 ·bar −1 ) and superior selectivity for Mg 2+ /Li + ( S Li, Mg of 15.8) under the dual optimization of membrane substrate and PA layer. In addition, it was demonstrated by molecular dynamics (MD) simulations that the B15C5 molecules in the B15C5-MX-NF membranes had a specific recognition ability of Li + to allow its preferential permeation, thereby enhancing the Mg 2+ /Li + selectivity of the membranes. This study provides a new idea for the preparation of NF membranes for efficient Mg 2+ /Li + separation.
研究领域:
材料科学
·
化学工程
·
膜技术
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2021
·
IF 8.742
Kayode Hassan Lasisi,Weihao Yao,Qiang Xue,Qin Liu,Kaisong Zhang
Acid-resistant nanofiltration (NF) membranes with both improved permeability and acid stability are in desperate demand for acidic wastewater treatment . Herein, we report a novel polyamine-based nanofiltration membrane with improved flux and excellent acid stability prepared via interfacial cross-linking polymerization reaction of branched polyethyleneimine (BPEI) and 1,4-benzenecarboxylic acid (TPA) with cyanuric chloride (CC) on porous polysulfone support. Evaluated using various characterization techniques, the optimized NF membrane achieved at 1.0% (w/v) BPEI, 0.10% (w/v) CC and 0.15 g/L TPA at 90 °C for 10 min exhibited high rejection of different model salt solutions in the order MgCl 2 > Na 2 SO 4 > NaCl, with excellent permeation flux up to 12.8 LMHbar −1 . Furthermore, membrane exhibited good acid stability even at extreme conditions. After exposure to 25% (w/w) H 2 SO 4 and 5% (w/w) HNO 3 acid solutions at 25 °C, 55 °C and 80 °C for 720 h, 72 h and 24 h respectively, the fluxes increased with a slight decline in their rejection levels. Meanwhile, a long hour stability test slightly dropped the MgCl 2 rejection level by ∼10%. The dynamic CuSO 4 /H 2 SO 4 mixed solution acid test of the membrane also revealed good permselectivity. This fabricated membrane thus provides a prospect of good application in acidic wastewater treatment and acid recovery process.
研究领域:
化学工程
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Jinxiong Song,Lijun Song,Biao Ai,Youcai Chen,Ying Liu,Yuzhang Zhu,Jian Jin
Thin-film composite (TFC) polyamide (PA) nanofiltration (NF) membranes are essential for separating ions and small molecules in the industries, including water treatment, chemical processing, energy production, and pharmaceuticals. These membranes are typically fabricated via interfacial polymerization (IP) on polysulfone (PSf) or polyethersulfone (PES) ultrafiltration (UF) supports. Apparently, optimizing the physicochemical properties of the UF support is very important for achieving TFC-PA NF membranes with superior separation performance. This study systematically investigated the influence of common pore-forming agents used in UF membrane fabrication, specifically polyvinylpyrrolidone (PVP), polyethylene glycol (PEG), and lithium chloride (LiCl), on the desalination performance of resulting TFC-PA NF membranes. We characterized the zeta potential, pore structure, and surface wettability of PSf UF membranes prepared with each pore agent. These characteristics were then correlated with the adsorption and desorption behavior of piperazine (PIP) monomers during the IP process. Our findings indicate that employing PVP as a pore-forming agent not only enhanced PIP adsorption within the UF support but also facilitated its rapid release during the IP reaction. This dual effect resulted in a PA selective layer with reduced thickness and smaller pore size. Consequently, the TFC-PA NF membrane fabricated on the PVP-modified UF support exhibited both higher water permeance and improved salt rejection. This research highlights the significant role of the pore-forming agent in determining the performance of TFC-PA NF membranes. The results suggest that UF supports prepared using PVP as a pore agent may be optimal for creating NF membranes with enhanced overall performance.
研究领域:
膜科学
·
分离技术
·
高分子科学
·
水处理
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）