JOURNAL OF MEMBRANE SCIENCE
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2024
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IF 8.4
Ke Xiang,Zhen-Liang Xu,Yong-Jian Tang
Recent studies have shown that the temperature and time of the heat curing process have important effects on the nanofiltration (NF) membrane structure and properties. However, the mechanism of the relative humidity (RH), as one of the important factors in the heat curing of NF membranes, is still unclear. To analyze the specific effect of RH, we compared the heat curing results of the NF polyamide (PA) membranes fabricated with different monomer concentrations at various RH. The nanofiltration performance of the membranes appeared to be non-uniform when the RH was in the range of 40 %–60 %. Within the appropriate RH range , the rejection of Na 2 SO 4 was preserved at about 98.5 % for the manufactured NF membranes. At high concentrations, the increasing RH created a discontinuous condensate layer on the PA layer surface, which affected the morphology and physicochemical properties of the NF membrane causing a doubling of pure water permeability (PWP) to 8.33 L m −2 h −1 ·bar −1 . At low concentrations, the PA layer was not significantly changed with the increase of RH, but the evaporation of water from the smaller capillary pores in its PES substrate was slowed down, which reduced the capillary stress on the substrate and prevented the collapse of the substrate pore size, resulting in a nearly 20 times increase in its PWP to 39.7 L m −2 h −1 ·bar −1 . This work reveals the effect of RH during heat curing and gives significant guidance to the design and synthesis of high-performance NF membranes.
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
RSC Advances
·
2016
·Vol. 6
·期 67
·62186-62192
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IF 3.289
Jianjian Cai,Shouyong Zhou,Yijiang Zhao,Ailian Xue,Yan Zhang,Meisheng Li,Weihong Xing
The hydrophilicity of a thermo-responsive PVDF/palygorskite-g-PNIPAAM hybrid ultrafiltration membrane was enhanced via surface segregation induced by coagulation bath temperature (CBT). The N1s content of the hybrid ultrafiltration membranes prepared at 5 and 20 °C is 1.77% and 1.02%, respectively while that of the membrane prepared at 40 °C is just 0.73%. This indicated that the PNIPAAM chains could be dragged to the membrane surfaces or pores via surface segregation induced by temperature. This resulted in higher hydrophilicity and permeability as well as thermo-responsiveness for membranes prepared at lower temperatures. The initial water contact angle of the PVDF/palygorskite-g-PNIPAAM hybrid ultrafiltration membrane prepared at 5 and 20 °C is 75.2° and 75°, respectively, which is about 6° lower than the one prepared at 40 °C. A higher pure water flux (PWF) of about 366 L m−2 h−1 at 40 °C was obtained for the hybrid membrane prepared at 5 °C while the one prepared at 40 °C only reached 274 L m−2 h−1. Meanwhile, membranes prepared at low temperature exhibited fewer macrovoids, lower membrane thickness and larger elongation.
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
RSC Advances
·
2014
·Vol. 4
·期 89
·48317-48321
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IF 3.708
Yun Yu,Weimin Hou,Xuebing Hu,Yang Yu,Le Mi,Lixin Song
A novel superhydrophobic Al2O3 microfiltration membrane was prepared by the layer-by-layer assembly of TiO2 coating with subsequent fluorination grafting surface treatment by 1H,1H,2H,2H-perfluorodecyltriethoxysilane. The influence of surface morphology on membrane superhydrophobicity, pore size diameter distributions and pure water permeability of the different membranes were studied. By optimizing the grafting parameters, a needle-like surface of grafted TiO2-coated Al2O3 membrane with a water contact angle of 169.5° was obtained. The pure water permeability of different membranes varied from 100 l m−2 h−1 bar−1 before grafting to 3–5 l m−2 h−1 bar−1 after grafting, and the grafted superhydrophobic membrane showed excellent water repellence. The novel superhydrophobic membrane is shown to be promising for liquid–liquid and gas–liquid separation.
研究领域:
材料科学
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表面工程
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2016
·
IF 5.557
Dong Zou,Minghui Qiu,Xianfu Chen,Yiqun Fan
Compared to the traditional separation technology, membrane separation is particular beneficial for the treatment of contaminated fresh water such as agricultural runoff, and hydraulic fracturing wastewater. However, the development of cost-effective membranes with both high permeability and high rejection performance is still a challenge. In this study, we design one-step preparation of high-performance bi-layer α-alumina ultrafiltration (UF) membranes supported on coarse tubular substrates via co-sintering process. In this approach, boehmite sol and alumina nanoparticles were mixed in different ratios for the fabrication of microfiltration (MF) layer and UF layer, respectively. The effects of dip-coating dispersion formulation, coating time and thermal treatment process on the membrane microstructure and performance were comprehensively investigated. It was found that the presence of boehmite sol in the MF layer could accelerate its sintering process, while the addition of alumina nanoparticles into UF layer could promote the phase transition from γ phase to α phase at low temperature and retard the shrinkage. The optimized doping content of boehmite and alumina nanoparticles were 2 wt% and 4 wt% to achieve a good match of thermal expansion properties between the two co-sintering layers. For MF layer and UF layer, the membrane thickness were controlled to be 40–50 µm and about 1 µm, respectively. After co-sintering at 1000 °C for 2 h with a heating rate and cooling rate of 0.5 °C/min, tubular α-alumina UF membranes were found to display a high pure water permeability of 70 L m -2 h -1 bar -1 and a small pore size of ~5 nm, which also exhibited good dye removal capabilities in the process of treating dye waste water.
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
CHEMICAL ENGINEERING RESEARCH & DESIGN
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2024
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IF 3.7
Yunwu Yu,Yan Wu,Yong Yuan,Yan Wang,Changwei Xu,Yanfeng Fang,Yaxin Gu,Peng Liu,Ye Wan,Lihua Wang,Xiaowei Sun
Based on the previous study, the properties, separation efficiencies, and anti-fouling performances of TiO 2 nanoparticle embedded PEEKWC/PEI cross-linked ultrafiltration membrane made via non-solvent-induced phase separation were investigated. SEM, contact angle measurement , ATR-FTIR, and other methods were used to characterize the membranes, and then the pure water flux (PWF) and dye rejection were measured. The TiO 2 nanoparticle embedded PEEKWC/PEI cross-linked ultrafiltration membranes were prepared by stepwise solution blending method. Compared to the pristine PEEKWC/PEI cross-linked ultrafiltration membrane, the anti-fouling and pure water flux performances were enhanced as the addition of TiO2 nanoparticles. The pure water flux of TiO 2 nanoparticle embedded membranes was significantly increased and could even reach 3368.2 LMH at 5 bar much greater than that of the pristine PEEKWC/PEI ultrafiltration membrane (1423.8 LMH), remaining a retention rate for BBR higher than 98.5%. And the TiO 2 nanoparticle embedded PEEKWC/PEI cross-linked ultrafiltration membranes exhibited a certain degree of increase of FRR (higher than 80%) after UV illumination. After a series of characterisation, the dye wastewater treatment property of membranes was assessed through filtration of Coomassie brilliant blue and Congo red solutions and researches were conducted on the anti-fouling capabilities of membranes. The TiO 2 nanoparticle embedded PEEKWC/PEI cross-linked ultrafiltration membranes exhibited self-cleaning efficiency with lower irreversible fouling ratio. The pure water flux recovery ratio following dye fouling was higher after being exposed to UV irradiation, which could be attributed to the TiO 2 nanoparticles' photocatalytic destruction of organic pollutants .
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
JOURNAL OF HAZARDOUS MATERIALS
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2019
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IF 7.65
Yanhong Zhang,Yuefeng Feng,Qi Xiang,Fuqiang Liu,Chen Ling,Fenghe Wang,Yan Li,Aimin Li
The development of high efficiency filter membranes, particularly those capable of removing trace heavy metals from drinking water sources, is a global challenge. In this study, a dual-functional membrane (P m G n @PVDF) was successfully developed by doping graphene oxide (GO) and then depositing polydopamine (PDA). The pure water flux (Jw) was 188 LMH/bar and Pb(II) could be effectively removed in the water volume of 2106.36 L m −2 . Both PDA and GO performed positive functions. PDA layer exhibited a high affinity toward Pb(II) by chelating with amino groups. And doping GO maintained a high pure water flux, which had been decreased by the extra PDA layer. In addition, the effective treatment volume of Pb(II) was elevated to 5029.06 L/m 2 by the co-existence of citric acid, since neutral PbHL coordinated with neutral NH 2 and cationic PbL- interacted with NH 3 + through electrostatic attraction. Furthermore, P m G n @PVDF showed the excellent anti-interference performance in high salt and nature organic matters solutions. Thus, this novel dual-functional membrane could be considered as a competitive alternative of NF/RO for the efficient and advanced removal towards heavy metals from natural water.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2015
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IF 3.453
Xianfu Chen,Wei Zhang,Yuqing Lin,Yuanyuan Cai,Minghui Qiu,Yiqun Fan
Membrane technology has become a low-cost and high-efficiency separation technology for industrial processes over the past decennia. The colloidal route is an environmentally benign process for the preparation of ceramic membranes by using water as solvent. A stable, colloidal boehmite sol with an average particle size of 16 nm was prepared from aluminum tri-sec-butoxide using water as a solvent in the pH range of 3–4. Acetic acid was used as the peptizing agent instead of nitric acid. The stable sol was used to fabricate γ-alumina nanofiltration membranes on α-alumina microfiltration substrates by a dip-coating approach. The effects of the peptizing agents on the properties of the sols and the membranes were investigated. γ-alumina nanofiltration membranes with an average membrane thickness of 1.8 μm were obtained after sintered at 600 °C for 2 h. The molecular weight cut-off of the γ-alumina nanofiltration membranes, as obtained by filtration of an aqueous PEG solution, was approximately 1 kDa. This membrane also showed a typical retention for monovalent ions and divalent ions. Additionally, the nanofiltration membranes exhibited a relatively high pure-water flux (>20 L/(m 2 h bar)), which is four times higher than that of the γ-alumina nanofiltration membranes reported in the literature. The contribution ratios of different microstructure factors on pure-water flux were calculated. The change in tortuosity with a contribution ratio of 75.6% was the main factor for the improvement of pure-water flux.
研究领域:
材料科学
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环境工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2020
·
IF 7.183
Jing Xue,Jianliang Shen,Runnan Zhang,Fei Wang,Shuwei Liang,Xinda You,Qianqian Yu,Yufeng Hao,Yanlei Su,Zhongyi Jiang
In this study, high flux β-CD/GQDs nanofiltration (NF) membranes were prepared by interfacial polymerization with β-cyclodextrin (β-CD) as the aqueous monomer , graphene quantum dots (GQDs) as the additive and trimesoyl chloride (TMC) as the organic monomer. The addition of GQDs not only modulated the membrane surface properties, but also led to the formation of a loose selective layer due to the nonspecific hydrogen bonding interactions between GQDs and β-CD. The pure water flux of the β-CD/GQDs NF membranes increased from 122.2 to 474.7 L/m 2 h (at the pressure of 0.1 MPa) when the concentration of GQDs increased from 0 to 0.5 wt%, almost 3.9 times higher than that of the pristine β-CD membrane. The dye rejection of Eriochrome Black T and Congo Red essentially remained above 93.0%. The β-CD/GQDs NF membranes with superior filtration performance and excellent chlorine resistance hold great promise in dye wastewater treatment .
研究领域:
材料科学
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环境工程
✓ 已验证
DOI
高影响因子
ACS Omega
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2019
·
IF 2.584
Jing Gao,Miyu Zhang,Jingtao Wang,Guanhua Liu,Hengrao Liu,Yanjun Jiang
Inorganic nanofiltration membranes with high flux are urgently needed in water purification processes. Herein, polydopamine (PDA)-modified layer-stacked molybdenum disulfide (MoS2) nanofiltration membranes (NFMs) were fabricated via a pressure-assisted self-assembly process. The separation performance of the as-prepared membranes with various MoS2 loadings at different dopamine polymerization times was evaluated. The pure water permeance of PDA-modified MoS2 NFMs, with MoS2 loading of 0.1103 mg/cm2 at 4 h modification, could reach 135.3 LMH/bar. The rejection toward methylene blue could reach 100% with molecular weight cutoff approximately 671 Da and a high permeability of salts. Furthermore, the resultant membrane also exhibited a satisfactory long-term stability toward dye solution and antifouling property toward bovine serum albumin. This work may give inspiration to the development of inorganic membranes with high performance, especially high pure water permeance, for water-related processes.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS SCIENCE FORUM
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2017
·
IF 0
Ye Kai Zhu,Da Jun Chen
Attapulgite (AT)-based nanofibrous membranes (NFMs) were fabricated via a facile papermaking procedure, and the AT-based NFMs were sintered at three different temperatures (240 °C, 400 °C, and 600 °C). The effect of sintering temperature on the structure and properties, such as specific surface area, pore size distribution, porosity, mechanical property, pure water fluxes of AT-based NFMs, were investigated. The results showed that average pore size, total pore volume, and porosity of AT-based NFMs increased with increasing of the sintering temperature, while specific surface area and flexural strength of AT-based NFMs decreased. The optimal sintering temperature for AT-based NFMs was 400 °C. In addition, it was also found that the swelling degree of AT-based NFMs in aqueous solutions was suppressed and the pure water fluxes of AT-based NFMs were improved by sintering process.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Na Zhang,Fanglu Fu,Wen Bo,Hussein Baqiah,Li Zhao,Wenbo Lu,Yadi Cai,Jiahui Tian,Tingting Yan,Saisai Li,Shuyun Zheng,Qiang Li
Two kinds of polyelectrolyte assembled membranes have been prepared using a rigid sulfonated polysulfone (SPSU) and a flexible poly(sodium 4-styrenesulfonate) (PSS) as anionic polyelectrolytes, respectively, with a polyethyleneimine (PEI) as a common cationic polyelectrolyte. The effects of molecular backbone’s rigidity and flexibility on the characteristics and performances of SPSU/PEI and PSS/PEI membranes have been investigated in detail. The SPSU/PEI membrane with two bilayers (SPSU/PEI-2.0) has a thinner and looser separation layer due to expanded molecular conformation and bulky benzene rings of the SPSU. In addition, the SPSU/PEI-2.0 membrane exhibits an ultrahigh pure water permeance up to 70.0 L m −2 h −1 bar −1 . The optimized separation performance for Congo red (CR)/NaCl and CR/Na 2 SO 4 displays the same high CR rejection of 99.6 %, low NaCl rejection of 1.2 % and Na 2 SO 4 rejection of 7.9 %. The SPSU/PEI-2.0 membrane also shows excellent acid-resistance stability, thermal stability and long-term operation stability. This research presents that choosing polyelectrolytes with appropriate molecular structures can be attractive when designing polyelectrolyte multilayer membrane to separate dye and salt.
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
MAIN GROUP CHEMISTRY
·
2022
·Vol. 21
·期 2
·481-489
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IF 0.641
Qu Jiale,Gao Shen,Hou Zhenghao
Polyvinylidene fluoride (PVDF) is a promising membrane material in ultrafiltration (UF) applications; its extensive application however is limited due to the disadvantage in hydrophilicity and low surface energy. Herein, a sort of TPU-modified PVDF membrane is prepared by blending method and its hydrophilicity is compared with a series of pure/modified PVDF membranes. The contact angle and pure water flux (PWF) results demonstrate that the hydrophilicity of the TPU-modified PVDF membrane is enhanced, and the performance is not inferior to that of traditional pore-modified PVDF membranes. SEM image shows that the TPU-modified PVDF membrane maintains morphology of the pure PVDF membrane, indicating that TPU molecules have excellent compatibility with PVDF molecules and can maintain the mechanical property of PVDF membrane to a certain extent. Finally, we explore the effects of TPU molecules and PVDF molecules on water molecules, respectively, from a microscopic perspective involving first principles. This investigation not only establishes that PVDF membrane has been prepared with enhanced hydrophilicity, but also provides a novel avenue for the modification of membrane properties.
研究领域:
材料科学
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膜技术
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分子模拟
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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）