JOURNAL OF APPLIED POLYMER SCIENCE
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2013
·Vol. 129
·期 6
·3473-3481
·
IF 1.395
Wan-Zhong Lang,Hai-Yan Niu,Ya-Xin Liu,Chun-Xia Liu,Ya-Jun Guo
The waste perfluoro-ion-exchange membranes (PFIEMs) in chlor-alkali industry were regenerated and used to the separation of dimethyl carbonate (DMC)/methanol (MeOH) mixtures by pervaporation process. The energy-dispersive spectrum (EDS) demonstrates that the impurities on the surfaces of waste PFIEMs can be effectively cleared by the regeneration process. The degree of swelling, sorption, and pervaporation properties of the regenerated PFIEMs with different counter ions were investigated. The results indicate that the counter ions of PFIEMs conspicuously influence the degree of swelling, sorption, and pervaporation properties for DMC/MeOH mixtures. The degree of swelling and solubility selectivity both decreases with the alkali metal counter ions in the sequence: Li + > Na + > K + > Cs + . The degree of swelling increases with MeOH concentration increasing in feed liquid. The pervaporation measurements illustrate that the permeation flux decreases and the separation factor increases with the rising in ion radius of counter ions. The increase of feed concentration (MeOH) and feed temperature is advantageous to improve permeation flux while at the cost of separation factor decreasing. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
研究领域:
高分子材料
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化学工程
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膜科学与技术
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环境化工
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分离科学
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2019
·
IF 7.015
Ziqiang Tong,Xiufeng Liu,Baoquan Zhang
A series of sphere-like polyelectrolyte complexes (PECs) and their homogeneous polyelectrolyte complex membranes (HPECMs) were synthesized by using sodium carboxymethyl cellulose (CMCNa) and poly(diallyldimethylammonium chloride) (PDDA). Different compositions or ionic complexation degrees (ICD) of PECs could be characterized by FT-IR spectra. The circular dichroism spectrum (CD) and field emission scanning electron microscopy (FESEM) were employed to examine the conformation and morphology of PECs, respectively. Zeta (ζ) potential was utilized to investigate the charge density of PEC particles while the surface hydrophilicity of HPECMs was studied by using contact angle (CA) meter. When subjected to ethanol dehydration, HPECMs revealed a satisfactory pervaporation performance and desired anti-trade-off phenomenon. For HPECM 0.31 and HPECM 0.57, the permeation fluxes were 2.25 kg m −2 h −1 and 2.93 kg m −2 h −1 , and the water content in permeate reached up to 99.35 wt% and 99.38 wt%, with respect to 10 wt% water in feed under 70 °C. All the results indicated that small-sized and sphere-like PECs were truly in favor of enhancing the pervaporation performance in ethanol dehydration.
研究领域:
高分子科学
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膜分离技术
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化学工程
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材料科学
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物理化学
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2018
·
IF 6.578
Heng Mao,Hong-Gang Zhen,Ali Ahmad,Ao-Shuai Zhang,Zhi-Ping Zhao
Biofuels separation using membranes becomes one of the research focuses in the field of renewable energy. In this study, a series of mixed matrix membranes (MMMs) with defect-free active layer around 1 µm thickness were elaborately prepared through interfacial synthesis for ethanol permselective pervaporation . Polydimethylsiloxane (PDMS) was employed as polymer matrix , which adjusted the nucleation of MOF precursors to in situ generate ZIF-8 nanoparticles . Within the active layer, the resultant ZIF-8 nanoparticles provided the preferential pathways for ethanol due to their ultrahigh adsorption capacity and super-hydrophobicity. Moderate aggregation could form the relatively continuous diffusion pathways. This approach rendered the uniform dispersion of ZIF-8 nanoparticles within PDMS matrix and their excellent compatibility. The ZIF-8 nanoparticles endowed the membranes with enhanced ethanol affinity, hydrophobic property, and thermal stability. More importantly, the ZIF-8 nanoparticles substantially reduced the permeation energy barriers of the membrane for penetrants. The membranes displayed the simultaneous increase in permeation flux and separation factor when utilized for ethanol recovery from aqueous solution, revealing the desirable anti-tradeoff effect. Particularly, the resultant membrane exhibited a superior pervaporation performance with relatively high permeation flux (1778 g · m -2 · h -1 ) and comparable separation factor (12.1) in separating 5.0 wt% ethanol aqueous solution at 40 °C.
研究领域:
可再生能源
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材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2013
·
IF 4.093
Xue-San Wang,Quan-Fu An,Qiang Zhao,Kueir-Rarn Lee,Jin-Wen Qian,Cong-Jie Gao
Solution-processable polyelectrolyte complexes (PECs) incorporated with both sulfate (OSO3) groups and carboxylic acid groups (COOH) were prepared from sulfated sodium carboxymethyl cellulose (SCMC) and poly(diallydimethylammonium chloride) (PDDA). Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy were utilized to characterize the chemical structures of SCMC and the compositions of SCMC/PDDA PECs. Membranes were made from PECs (SPECMs), and their surface properties were studied by field emission scanning electron microscopy and contact angle characterizations. Moreover, SPECMs were subjected to pervaporation dehydration of aqueous ethanol solution. Effects of SPECMs’ chemical compositions and operation conditions on pervaporation performance were studied and discussed in terms of membrane structures. It was found that OSO 3 groups were incorporated into SPECMs in the form of sulfate–amine ion-pairs, and they improved both the selectivity and flux in the dehydration of aqueous ethanol solution. For instance, the flux and water content in permeate for SPECM-0.34 in dehydration of 10 wt% water–ethanol mixture at 70 °C were 1760 g m −2 h −1 and 98.7 wt%, respectively, both of which were much higher than those for pristine PEC membranes with no sulfate groups. Moreover, the high separation performance of SPECMs was stable and both the tensile strength and elongation at break increased with increasing strong ion-pairs content. For instance, the SPECM-0.34 tensile strength and elongation at break were 64.5 MPa and 9.33%.
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
AICHE JOURNAL
·
2021
·Vol. 68
·期 3
·e17560
·
IF 3.993
Junjun Li,Mi Huang,Ping Wei,Yaqin Zhang,Xuean Zhao,Chunbo Liu,Zhijun Zhou,Lin Zhang
Poly(vinyl butyral) (PVB) is selected as a promising ethanol-permselective membrane based on the solubility parameter theory; however, it exhibits anomalous water perm-selectivity in practical pervaporation (PV) process. Comprehensive analysis based on experimental and theoretical methods were carried out to explore the inherent mechanism of the anomalous performance. Firstly, sum frequency generation vibrational spectra and contact angle were developed to quantify the surface reconstruction of membrane in air and ethanol, which indicated that hydrophilic hydroxyl tended to expose on membrane surface with ethanol thus improving the membrane affinity to water. Meanwhile, swelling behaviors proved more water would accumulate in the ethanol swollen membrane. Furthermore, theoretical analysis in terms of sorption and diffusion process, based on the UNIFAC-FV model and Fujita free-volume theory, confirmed the mechanism of anomalous phenomenon of PVB membrane. The comprehensive investigation was expected to provide insights into the basic separation mechanism of PV process.
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
·
IF 7.312
Dovletjan Taymazov,Hao Zhang,Wen-Xuan Li,Ping-Ping Li,Fei Xie,Xin-Yu Gong,Sheng-Ning Zhang,Xiao-Hua Ma,Zhen-Liang Xu
Due to environmental issues and intense competition in the marketplace, industries and governmental organizations invest in new technology research to improve productivity, environmental protection, and cost-efficiency. Pervaporation is a membrane-based separation technology, which is cost-effective, environmentally friendly, and efficient in the separation of azeotropic mixtures. Here, we report the fabrication of a hybrid membrane based on molybdenum disulfide (MoS 2 ) material, which can be used to dehydrate alcohol through a pervaporation process. Ceramic hollow fiber (CHF) membrane was used as a substrate in MoS 2 hybrid membrane, and TiO 2 intermediate layer was constructed to reduce the macropores on the CHF surface. Polyethyleneimine (PEI) was used as a binder in the fabrication of the MoS 2 layer. MoS 2 -PEI layer was prepared by vacuum suction method and then crosslinked with trimesoyl chloride (TMC) to prevent the hybrid layer from swelling in an aqueous solution. We investigated the morphology and physicochemical characteristics of the hybrid membranes by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), atomic force microscopy (AFM), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and water contact angle (WCA) measurements. The fabricated MoS 2 hybrid membrane possesses a permeation flux of 5697 g m -2 h −1 and separation factor of 320 in a 90 wt% isopropanol aqueous solution at 343 K. In this study, we provide a comprehensive understanding of the fabrication of MoS 2 hybrid membrane on the CHF membrane for efficient dehydration of isopropanol via the pervaporation process.
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高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2020
·
IF 7.183
Zhihao Si,Chang Liu,Guozhen Li,Ze Wang,Jingfang Li,Tanlong Xue,Shuai Yang,Di Cai,Shufeng Li,Haoning Zhao,Peiyong Qin,Tianwei Tan
The ultrashort and controllable membrane-forming process is highly required in large-scale production of PDMS membrane. To shorten the cross-linking time, an UV-induced ring-opening polymerization of the epoxide groups was introduced to the preparation of PDMS membranes. PDMS was firstly functionalized with epoxide groups, providing the possibility of being cross-linked under UV irradiation. With this strategy, the membrane curing was finished within 200 s, hence shortened by two orders of magnitude in comparison with the conventional thermal-driven method. Meanwhile, the cationic photoinitiation of epoxide groups can be achieved without oxygen inhibition in an open-air environment. Moreover, the viscosity of the coating solution in the groove is kept constant when protected from light, thus meeting the requirement of the coatability. When applied to the pervaporation of a 1.5 wt% 1-butanol/water solution at 55 °C, the measured 1-butanol separation factor was 45 and the total flux was 1119 g m −2 h −1 . This novel strategy shows a great prospect in the continuous preparation of membrane.
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高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Xiangqiong Wang,Naixin Wang,Hongxu Ni,Tong Liu,Quan-Fu An
Pervaporation is considered to have great potential for application in the field of organic-solvent dehydration. In this study, a type of keto-enamine-linked covalent organic framework TpPa (synthesized using the Schiff-base reaction of 1,3,5-triformylphloroglucinol [Tp] with p -phenylenediamine [Pa]), was fabricated on commercial polyacrylonitrile (PAN) ultrafiltration membranes through an oxygen-plasma assisted contra-diffusion self-assembly strategy for organic-solvent dehydration. The PAN membranes with a glycerol exhibited a better separation factor for dehydration of organic solvents than those without a glycerol layer. The influence of oxygen plasma and glycerol on the formation of the TpPa membrane was investigated. The best plasma treatment condition and optimum glycerol impregnation concentration were determined as a device power of 60 W and 30 wt%, respectively. Defect-free TpPa membrane formation took only 24 h. The as-prepared TpPa membrane exhibited a separation factor of 1491 and a high permeation flux of 2530 g m −2 h −1 for a 90 wt% isopropanol–water mixture. The separation performance of the TpPa membrane was stable for >100 h, exhibiting great potential in organic-solvent dehydration.
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2018
·
IF 3.927
Shufeng Li,Zhe Chen,Yinhua Yang,Zhihao Si,Pei Li,Peiyong Qin,Tianwei Tan
The hydrophobicity of porous particles is important for the performance of mixed-matrix membranes for pervaporation separation of n -butanol aqueous solution. Here, a strategy was proposed to further enhance the hydrophobicity of ZIF-8. ZIF-8 particles were first coated by polydopamine (PDA) to create chemically reactive surface and then modified with silane coupling agents n -propyltrimethoxysilane and n -octyltriethoxysilane. The water contact angles of the obtained P-ZIF-8@PDA and O-ZIF-8@PDA separately increased from 132.8° to 137.3° and 151.5°, which demonstrated a remarkable enhancement in hydrophobicity. The silane-modified ZIF-8 particles were subsequently incorporated into PDMS to fabricate mixed-matrix membranes, which exhibited an improved adsorption selectivity for butanol. The best membrane with 1 wt% loading (O-ZIF-8@PDA) exhibited a separation factor of 56 and butanol flux of 480.6 g m −2 h −1 for a 1.5 wt% butanol solution at 55 °C. The separation factor increased by 23% compared with that of a ZIF-8/PDMS membrane. Moreover, compared with those of a pure PDMS membrane, the separation factor and butanol flux increased by 34% and 85%, respectively. Thus, the strategy is an effective method to improve the PV performance of PDMS membranes for butanol separation.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2019
·
IF 6.97
Ebrahim Ataeivarjovi,Zhigang Tang,Jian Chen,Zhijun Zhao,Guo Dong
Currently, there is strong interest in carbon capture and absorption as a means of reducing carbon dioxide emissions and combating climate change. Unfortunately, the current and traditional methods to achieve such goals are not economical, because they require a huge absorption–desorption plant with high investment and operating costs and high recycle rates of chemical absorbers. In this paper, we propose a novel CO2 capture method combining dimethyl carbonate as a physical solvent and polydimethylsiloxane (PDMS)/TiO2 nanocomposite as a desorption membrane. The effects of TiO2 concentration, feed temperature, and permeate pressure on the pervaporation process for CO2 capture were studied. Results showed that the addition of TiO2 nanoparticles (up to 5 wt %) resulted in 3.61 kg/m2·h flux and 44.68 selectivity of the membrane. The presence of TiO2 nanoparticles in the PDMS membrane not only increased the performance of membrane’s but also reduced (about 72%) energy consumption. To corroborate our experimental findings, a simple simulation was conducted by Gaussian 09. The modeling results demonstrated that the incorporation of TiO2 nanoparticles to the PDMS led to favorable absorption of CO2 compared with the composite one. These results indicate a novel and promising method to capture CO2 effectively and economically for industrial purposes.
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2019
·
IF 5.107
Yunli Zhai,Baoquan Zhang,Xiufeng Liu,Ziqiang Tong
Spherical polyelectrolyte complexes (PECs) sized at 10–20 nm were synthesized to fabricate homogeneous polyelectrolyte complex membranes (HPECMs). The PEC dispersions at various concentrations were employed to manipulate the thickness of HPECMs. Zeta potentials were measured to quantify the charge density of PECs. Scanning electron microscopy was utilized to examine membrane morphology and thickness. The surface hydrophilicity of HPECMs was evaluated by using static water contact angles. Being subjected to isopropanol dehydration, the synthesized HPECMs with nano-sized spherical PECs exhibited excellent separation performance, good stability and durability. The HPECM with the thickness of 1.1 μm displayed a significantly high permeation flux (6.12 kg m –2 h −1 ) with an ideal water concentration in permeate (99.85 wt%). The use of nano-sized spherical PECs ensured the homogeneous nature of synthesized polyelectrolyte complex membranes, leading to the enhancement of pervaporation performances in isopropanol dehydration. The extension of this work would trigger a large-scale application of HPECMs for dehydration of organic solvents.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2015
·Vol. 132
·期 34
·
IF 1.768
Xiangyan Liu,Deng Hu,Meng Li,Jianming Zhang,Zhigao Zhu,Gaofeng Zeng,Yanfeng Zhang,Yuhan Sun
To improve the pervaporation performance of Silicalite-1/PDMS composite membrane by adding a small amount of Silicalite-1 zeolite, novel Silicalite-1/PDMS surface sieving membranes (SSMs) were prepared by attaching Silicalite-1 particles on the PDMS membrane surface. The obtained membranes and traditional mixed-matrix membranes (MMMs) were characterized by SEM, XRD, TGA, FT-IR, and pervaporation separation of ethanol–water mixture. Effects of Silicalite-1 particles content, feed temperatures, and feed compositions on the separation performance were discussed. From the cross-section view SEM images of SSMs, a two-layer structure was observed. The thickness of the Silicalite-1 layer was about 300 nm to 2 μm. The TGA analysis indicates that the zeolite concentration in 3 wt % SSM is lower than 10 wt % MMMs. In the ethanol/water pervaporation experiment, the separation factor of Silicalite-1/PDMS SSMs increased considerably compared with pure PDMS membrane. When the suspensions concentrations of Silicalite-1 particles reached 3 wt %, the separation factor was about 217% increase over pure PDMS membrane and 52.9% increase over 10 wt % Silicalite-1/PDMS MMMs. As the ethanol concentration in the feed increases, the separation factor of SSMs increases, whereas permeation flux decreases. At the same time, with increasing operating temperature, the permeation flux of SSMs increased. The stability of SSMs at high temperature is better than the traditional MMMs. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 42460.
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高影响因子
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