DESALINATION
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2022
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IF 11.211
Songchen Xie,Ngie Hing Wong,Jaka Sunarso,Qiang Guo,Chunguang Hou,Zhiguang Pang,Yuelian Peng
Mineral scaling is one of the major challenges for membrane distillation in concentrating high-salinity brine. This work first investigated the characteristic of CaSO 4 scaling, then explored different cleaning reagents to evaluate their efficiencies and mechanisms. By analyzing the SEM and EDX mapping images, the CaSO 4 scaling process could be divided into surface and pore scaling stages. Three cleaning solutions, i.e., commercial detergent (20 %), EDTA-4Na (0.05 M), and MgCl 2 (0.8 M), were chosen for their high CaSO 4 solubility (0.7 g CaSO 4 per 100 g H 2 O). At the surface scaling stage, three cleaning solutions exhibited excellent removal of CaSO 4 scaling with approximately similar 96 % cleaning efficiencies. However, at the pore scaling stage, only the commercial detergent showed high efficiency (89 %). Such high cleaning efficiency was mainly attributed to the detergent's high total dissolved solids (salinity), low pH, and high diffusion rate (5.46 μm cm −1 min −1 ) across the membrane. Moreover, periodic cleaning at the surface scaling stage with the commercial detergent followed by drying throughout a 43.5 h continuous concentration test on an actual RO brine could restore the PTFE membrane performance completely, giving 90 % of the total water recovery . This work provides new insights into the cleaning mechanism for gypsum scaling in a hydrophobic porous membrane.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Simin Yang,Jianqiang Wang,Yang Wang,Yajie Ding,Weilin Zhang,Fu Liu
Interfacial polymerization has been considered as a benchmark strategy for polyamide membrane fabrication. However, controlled reaction is still challengeable. Herein we propose a novel emulsion mediated interfacial polymerization strategy for controllable polyamide nanofiltration fabrication. Hexane micro-droplets containing trimesoyl chloride (TMC) molecules were adsorbed, demulsified and transported to the interface from hexane-in-water emulsion by a hydrophobic and oleophilic polytetrafluoroethylene (PTFE) membrane for further controlled reaction with piperazine (PIP). Surface morphologies, layer thickness, surface chemistry, crosslinking and water contact angle of resulted polyamide membranes were studied with varying reaction time, displaying the control for interfacial polymerization. PTFE membrane assisted interfacial polymerization strategy leads to smoother (Ra = 8.0 nm) and thinner (25 nm) polyamide layer compared with conventional interfacial polymerization. The resulted membrane exhibits comparable nanofiltration performances (water permeability: 7.3 Lm −2 h -1 bar −1 , Na 2 SO 4 rejection: 92.3%) with conventional membranes. The current study provided a new avenue for controllable interfacial polymerization.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2020
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IF 7.183
Jinxue Cheng,Qinglin Huang,Yan Huang,Shiwen Yu,Changfa Xiao,Quan Hu
In this research, a novel poly(tetrafluoroethylene) (PTFE) membrane with regular geometric pore structure fabricated by near-field electrospinning (NFES) method was firstly utilized in the preparation of water-in-oil (W/O) emulsion through membrane emulsification process. Effects of NFES PTFE membranes’ pore aspect ratio (length-width ratio of rectangle pore structure) on the water-in-oil droplet size, droplet size distribution, and uniformity of water-in-oil emulsion was investigated respectively. Results showed that the increase of pore aspect ratio would bring about a smaller water-in-oil droplet size. The average water-in-oil droplet size decreased from 234.9 nm (M-1) to 167.8 nm (M-4) when the pore aspect ratio increased from 1 to 4. Compared with conventional mechanical agitation, the water-in-oil emulsion formed by membrane emulsification process showed not only more uniform water-in-oil droplet size, but also higher long-term stability (remained homogeneous after 30 days). In addition to showing the excellent membrane emulsification performance in harsh environment, the NFES PTFE membrane also exhibited excellent water-in-oil emulsion separation performance. Compared with other NFES PTFE membranes, M-1 membrane showed the highest oil flux (33.4 L m -2 h -1 , -0.02 MPa) and water rejection rate (94.4%) in the separation of water-in-oil emulsion formed by membrane emulsification process.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2019
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IF 7.015
Zhihao Zhu,Guodong Kang,Ying Sun,Sha Yu,Meng Li,Jie Xu,Yiming Cao
The batch and continuous synthesis of glycolic acid via carbonylation of formaldehyde using high-temperature and high-pressure poly(tetrafluoroethylene) (PTFE) membrane contactor was demonstrated in this paper. The experiments in conventional stirred tank reactor were also conducted for comparison. The results showed that the yield of glycolic acid was significantly improved in membrane contactor system compared to the stirred tank reactor. At reaction temperature of 120 °C and reaction pressure of 5.0 MPa, the yield of glycolic acid was higher than 90% when the reaction time was 1 h, while it was only about 45% in the conventional stirred tank reactor. The enhancement of yield was due to the improvement of mass transfer or dispersion of CO in membrane contactor system, which could provide larger gas-liquid contact area and shorter mass transfer distance. The stability of PTFE hollow fibre membranes was also investigated by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), liquid entry pressure (LEP), bubble point (BP) and contact angle (CA) measurements. The characterizations indicated that PTFE membranes exhibited good chemical and thermal stability in this reaction system. This study provided new idea and reference for the carbonylation of formaldehyde and similar gas-liquid reactions.
研究领域:
化学工程
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材料科学
✓ 已验证
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
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2021
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IF 5.876
Jinxue Cheng,Naijia Zhao,Yan Huang,Changfa Xiao,Xiao Ma,Qinglin Huang
Background Membrane emulsification (ME) is an attractive membrane process to produce various kind of simple or multiple emulsions. The membrane utilized in ME process should have high dispersed phase flux, narrow pore size distribution and excellent antifouling property. Methods This work proposed a novel near-field electrospun (NFES) poly(tetrafluoroethylene) (PTFE) membranes with ordered rectangular pore geometry. Compared with other membranes, the order pore geometry of NFES PTFE membrane was helpful to obtain a more homogeneous and more stable water-in-oil (W/O) emulsion. Significant findings The droplet size was simply controlled by the NFES PTFE membrane pore size. And NFES PTFE membrane was more conducive to the formation of droplets with narrow droplet size distribution because of its unique straight rectangular membrane pore geometry. In addition, W/O emulsion droplet size be regulated in coordination with operating parameters and phase parameters. Results indicated that a smaller rectangular pore area of PTFE membrane would lead to a smaller droplet size. Introducing of shear stress in the continuous phase was contributed to the generation of monodisperse droplets. When the emulsifier (Span 80) content was 1wt%, the smallest droplet size (∼103.6 nm) was obtained.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ENERGY
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2022
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IF 8.857
Hongming Fu,Kaili Xue,Zhaohao Li,Heng Zhang,Dan Gao,Haiping Chen
Excessive CO 2 emissions contribute to global warming, which may cause potential threat to survival of humans and other creatures, and it is necessary to take effective measures to curb CO 2 emissions. Gas-liquid membrane contact CO 2 separation technology is an emerging CO 2 capture technology that combines advantages of membrane separation and chemical absorption . In this paper, differences of CO 2 capture performance between ceramic and polytetrafluoroethylene (PTFE) membranes with pore size of 10 nm and 100 nm are investigated comprehensively. The morphological structure, pore size distribution, wettability and membrane flux of ceramic and PTFE membranes are analyzed by membrane characterization. Moreover, with monoethanolamine (MEA) as absorbent, CO 2 capture performance under different operating parameters (e.g., absorber flow rate and temperature, gas flow rate and pressure) is investigated through experiments based on ceramic and PTFE membrane modules . The CO 2 capture efficiency of ceramic and PTFE membrane is 94.7% and 99.3%, respectively. However, the mass transfer rate of ceramic membrane is much higher than that of PTFE membrane. The results show that ceramic membrane exhibits favorable CO 2 capture performance under appropriate operation parameters. This paper will provide theoretical and technical references for subsequent industrial CO 2 capture applications.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Water
·
2024
·Vol. 16
·期 12
·1747
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IF 3
Wenfeng Zai,Yangman Chen,Qingdong Qin,Xiangkun Li,Dezhao Liu
HighlightsPlasma-grafting acrylic acid composite membrane for MABR was prepared.Higher O2transfer rate and better hydrophilicity for modified membranes than pristine.Modified PVDF membrane demonstrated superior nitrogen removal during startup.Activity of denitrifying bacteria was enhanced in the modified PVDF MABR.AbstractMicroporous membranes such as polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF) often exhibit suboptimal hydrophilicity and microbial adhesion, which impede effective nitrogen removal in membrane-aerated biofilm reactors (MABRs), particularly during initial operational phases. To address this issue, the present study introduced acrylic acid (AA) following plasma treatment (P) to enhance membrane performance, thereby engineering a novel composite material optimized for MABR applications. Four MABRs—Reactor with pristine PVDF membrane (R-PVDF), Reactor with composite PVDF membrane (R-PVDF-P-AA), Reactor with pristine PTFE membrane (R-PTFE), and Reactor with composite PTFE membrane (R-PTFE-P-AA)—were evaluated. The modified membranes displayed enhanced roughness and hydrophilicity, which improved biocompatibility and variably increased the oxygen transfer efficiency. Notably, the R-PVDF-P-AA configuration showed a significant enhancement in the removal rates of NH4+-N and total nitrogen (TN), achieving 78.5% and 61.3%, respectively, which was markedly higher than those observed with the original membranes. In contrast, the modified R-PTFE-P-AA exhibited lower removal efficiencies, with NH4+-N and TN reductions of approximately 60.0% and 49.5%. Detailed microbial community analysis revealed that the R-PVDF-P-AA membrane supported robust commensalism between ammonia-oxidizing and denitrifying bacteria, underpinning the improved performance. These findings highlight the critical role of surface chemistry and microbial ecology in optimizing the function of MABRs.
研究领域:
环境工程
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微生物学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
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2023
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IF 4.6
Yuanlu Xu,Yi Zhu,Chunyang Song,Yinan Chen,Chengwen Song,Zaijin You,Xinfei Fan
Oil spills and oily wastewater from various industries caused severe harm to the environment and human life. Then the effective treatment of oily wastewater is extremely urgent. Superhydrophilicity/underwater superoleophobicity membranes are considered as a favorable choice for the separation of oily wastewater. In this work, inspired by mussel adhesive protein chemistry , the SiO 2 /PDA/PTFE membrane (SPP) with hydrophilic chemical components and multi-scale rough structures was prepared by the facile combination of dopamine self-polymerization and sol-gel strategy. The hydrophilic SiO 2 nanoparticles (NPs) and polydopamine layer can be co-deposited on the membrane surface through Michael addition reaction, thus avoiding the problem of coating damage during oil/water separation. Moreover, the SiO 2 /PDA layer has hydrophilic groups and micro/nano rough structure, which makes the SPP membrane possess superhydrophilic and underwater superoleophobic properties. The properties of SPP membrane facilitate the formation of a hydration layer on the membrane surface, thus minimizing direct contact with oil droplets. During the experiment of oil/water separation, SPP membrane demonstrated excellent separation ability, the permeation flux of SPP membrane was measured to be 6183 and 4389 L m −2 h −1 for oil-water mixture and oil-in-water emulsion, respectively. The oil/water separation efficiency had also reached more than 99.7%. In addition, the SPP membrane exhibited brilliant chemical stability under harsh environments. It is worth mentioning that the SPP membrane showed superior cycling and anti-fouling performance in the separation process. These excellent performances demonstrate the great potential of SPP membranes in the industrial applications.
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
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Qin Liu,Xin Liu,Bo Wu,Changge Wang,Tiantian Li,Wancheng Li,Yun Huang,Yao Li,Haiyang Yan,Chuanrun Li
This study harnessed polydimethylsiloxane (PDMS)-coated polytetrafluoroethylene (PTFE) composite (PDMS/PTFE) membranes for the separation of peppermint aromatic water in vapor state. The effects of the PDMS coatings’ morphology structure on the separation performance of the membrane were investigated. The vapor permeation process, selective-permeation mechanism, and membrane stability were explored. Results showed that the separation effect of the membranes depended on the degree of polymerization of PDMS coating. Almost no water molecules can pass through the membrane during the 6 h separation process, and the separation factor was as high as 668. The main pharmacodynamic components in the separated permeate were L-menthol, L-menthone, and menthyl acetate, accounting for 49.16 %, 26.3 %, and 5.46 %, respectively, which conformed to the standard of the European Pharmacopoeia . The parameters of membrane separation showed that the maximum permeability coefficients of L-menthol, L-menthone, menthyl acetate, and water were 40.80, 20.28, 4.211, and 0.3945, respectively, at 105 °C and 65 kPa. This finding indicated that the large difference in permeability coefficient was the key to the excellent selectivity of the PDMS/PTFE membrane for separating volatile pharmaceutical components and water molecules in the peppermint aromatic-water system.
研究领域:
材料科学
·
药学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2016
·
IF 5.557
Sikuai Xue,Chengcai Li,Jiuming Li,Hailin Zhu,Yuhai Guo
To improve hydrophilicity and anti-fouling property of the polytetrafluoroethylene (PTFE) flat microfiltration (MF) membrane, a facile method was developed to modify the membrane via the co-deposition of catechol (CA) and polyethyleneimine (PEI) followed by surface mineralization of γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH560). The surface chemical composition, surface morphology, hydrophilicity and filtration performance of the PTFE flat membrane were investigated by ATR-FTIR, XPS, FESEM, WCA and pure water flux measurements, respectively. After using this low-cost and simple modification method, the PTFE flat membrane was endowed with excellent hydrophilicity, high water permeation flux and superior anti-fouling property. Then, the oil/water separation tests were conducted using the modified PTFE flat membranes. The size distribution of the oil droplets is between 0.12–1.44 µm and the mean pore size of pristine PTFE flat MF membrane is 0.22 µm. The as-prepared hydrophilized PTFE flat membranes possess an excellent oil resistant ability with oil rejection ratio near 99%. Finally, the surface stability of the modified membrane was studied and the mineralized membrane showed excellent acid resistant ability. Therefore, this facile strategy holds attractive potential practical application in water environmental remediation.
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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表面化学
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水处理
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2020
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IF 7.183
Jinxue Cheng,Qinglin Huang,Yan Huang,Wei Luo,Quan Hu,Changfa Xiao
Novel poly(tetrafluoroethylene) (PTFE) membranes with regular geometric pore structure were fabricated via near-field electrospinning (NFES) method. Firstly, computer aided design (CAD) was utilized to design membrane's pore geometry (triangle, diamond, square, hexagon and their different size). Secondly, the PTFE spinning solution consisted of PTFE emulsion and carrier (PVA aqueous solution) was electrospun into nascent PTFE/PVA membrane, which had regular geometric pore structure. Finally, the nascent membrane suffered sintering process, and the NFES PTFE membrane was obtained. Effects of PTFE/PVA mass ratio, sintering temperature and annealing condition, pore geometry on the membrane morphology, structure and properties were investigated, respectively. Results found that the square membrane showed good combination of membrane performances and properties, when PTFE/PVA mass ratio was 6:1 and sintered at 380 °C followed by cooling in muffle furnace. Owing to the excellent hydrophobicity , the obtained PTFE membranes exhibited excellent oil/water separation performance in terms of high oil flux (707 L m -2 h -1 ) without extra pressure, and high separation efficiency (rejection up to 99.6%). Owing to the regular and accurate pore structure, the PTFE membrane was utilized in the particle sequential separation. The mixed silica (SiO 2 ) particles with a series of diameter (1, 5, 10, 20 μm) were sequential separated by PTFE membranes with different pore geometry, and the rejection reached up to 82.0%.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2021
·
IF 8.742
Jinxue Cheng,Naijia Zhao,Yuxin Zhang,Yan Huang,Qinglin Huang,Changfa Xiao
Uniform-sized core-shell microspheres have received more and more attentions owing to the therapeutic application such as controlled release and drug targeting. In this work, we proposed a facile method to fabricate core-shell microspheres with uniform size. Polymethyl methacrylate (PMMA)@polylactic acid (PLA) core-shell microspheres with controllable core and shell size were prepared by combining membrane emulsification (ME) technology and solvent evaporation method. Specially, the near-field electrospinning (NFES) poly(tetrafluoroethylene) (PTFE) membranes and biaxially stretched PTFE membranes were utilized in the ME process. Subsequently, a series of PMMA@PLA core-shell microspheres were successfully prepared, where the core size of microspheres depended on the hydrophobic NFES PTFE membrane while the shell size depended on the hydrophilic biaxially stretched PTFE membrane. Meanwhile, the variation of droplet size and distribution with the evaporation temperature, pressure and continuous phase rotating speed were also investigated. When the solvent evaporation temperature was 40 °C, the obtained PMMA@PLA core-shell microspheres showed optimal morphology and size distribution. Moreover, the shell size increased with the increase of operating pressure and the decrease of continuous phase rotating speed. This facile strategy showed great potential for efficiently preparing uniform-sized core-shell microspheres in large scale.
研究领域:
材料科学
·
制药工程
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生物医学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）