JOURNAL OF MEMBRANE SCIENCE
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2020
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IF 7.183
Zhigao Zhu,Lingling Zhong,Xuemei Chen,Wei Zheng,Jinlong Zuo,Gaofeng Zeng,Wei Wang
The treatment of hypersaline wastewaters with membrane distillation (MD) is significant but challenging, owing to the critical limitations of severe membrane wetting and fouling. Herein, a monolithic and self-roughened Janus fibrous membrane (FM) with asymmetrical superwettability was developed via sequential electrospinning and electrospraying in combination with thermal treatment. We detailedly discussed the formation mechanism of the roughness on the fiber surface via electrospinning/electrospraying technique and explored the asymmetrical wettability and the monolithic performance of Janus FM for the synergistic resistance of membrane wetting and fouling. Benefiting from the high in-air water contact of 157° of the omniphobic surface, the high underwater oil contact angle of 156° of the superhydrophilic skin layer, as well as the monolithic performance of the resultant membrane, the newly developed Janus FM achieves a high water flux of over 27 L m −2 h −1 and high desalination efficiency of ~100% when desalination of the simulated hypersaline wastewater composed of 3.5 wt% of NaCl, 0.1 g of SDBS and 1.0 g of lubricating oil. The presented strategy on Janus FM fabrication is believed to open a new direction to prepare monolithic, self-roughened, and asymmetrically superwettable Janus FM and applied in a wide field of other selective separation applications.
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
ACS ES&T Water
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2022
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IF 0
Tengjing Gong,Danting Shi,Zhigao Zhu,Bin Liu,Senlin Shao
Hydrophobic membranes are very susceptible to pore wetting when they contact the feed water containing surfactants or low-surface-tension liquids in membrane distillation (MD). Avoiding direct contact between feed water and hydrophobic membrane pores is a potential strategy to control membrane pore wetting. In this study, we successfully fabricated a polyamide thin-film composite (TFC) Janus membrane through interfacial polymerization, with a hydrophobic microporous membrane as the substrate. The fabricated TFC Janus membrane showed a super antiwetting ability when treating the hypersaline water containing surfactants (>0.4 mM sodium dodecyl sulfate) or ethanol (>40% v/v). The optical coherence tomography (OCT) observation revealed that no liquid water was present at the distillate-facing side of the polyamide layer. Therefore, we ascribed the super antiwetting ability to the fact that the polyamide layer could prevent the feed liquid from directly contacting hydrophobic pores. The TFC Janus membrane could also avoid the wetting induced by gypsum scaling because the polyamide layer could act as a barrier to hinder the intrusion of gypsum crystals into hydrophobic pores. In addition to the antiwetting ability, the TFC Janus membrane showed 10–20% increases in vapor flux, despite the existence of a dense polyamide layer. Because interfacial polymerization is the most commonly used method for the fabrication of commercial TFC membranes, this study provides a facile and scalable method to fabricate membranes with robust antiwetting ability.
研究领域:
材料科学
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环境工程
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化学工程
✓ 已验证
产品关联
DOI
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Jingtong Yu,Dongmin Yue,De Sun,Bingbing Li,Yanxia Ge,Yuanhang Lin
Solar-driven photothermal conversion vacuum membrane distillation (SVMD) becomes an energy-efficient water treatment thanks to the thermal localization of photothermal membranes. Membrane photothermal activity and distillation performance are essential for creating photothermal composite membranes. Herein, a CuO/CF-PVDF photothermal composite membrane has been designed with flower-like copper oxide (CuO/CF) photothermal active-layer and polyvinylidene fluoride (PVDF) microporous hydrophobic separation layer. Firstly, the flower-like CuO/CF layer with the light trapping was obtained by in-situ surface oxidation on the copper foam (CF) surface. Then, by the NIPS method, PVDF microporous hydrophobic layer was scraped on one side of the CuO/CF photothermal active-layer and firmly fixed on the porous surface of CuO/CF layer by anchoring effect. The light trap consisted of CuO micron flowers and Cu(OH) 2 nanowires. The gaps among the petals increased the light refractive rate and absorption area, thus enhancing the photothermal performance of the CuO/CF. Under 1 kW‧m −2 solar irradiation, the absorption rate reached up to 95 %, and the photothermal conversion efficiency achieved 94 %. For the SVMD process, compared to current research, the CuO/CF-PVDF achieved the permeate flux of 3.34 kg‧m −2 ‧h −1 and energy efficiency of 88 % under average feed temperature. Overall, the CuO/CF-PVDF membrane has promising potential for desalination by fully using sustainable energy.
研究领域:
材料科学
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环境工程
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2021
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IF 8.742
Wei Zhang,Zhi Wang,Baoan Li
Omniphobic membranes have acquired some recognitions for alleviating the membrane wetting in the robust membrane distillation because of the super-repulsion towards different surface tension liquids. In this study, the Ti-CNFs/PVDF composite membrane with omniphobicity and high permeate flux was fabricated via electrospraying multilevel heat-conducting nanofibers on the PVDF membrane and fluorosilane treatment simultaneously with one-step strategy. In detail, carbon nanofibers decorated by TiO 2 with hydrothermal treatment were immobilized on the surface by the adhesive attraction of PDMS to establish the re-entrant structure. Meanwhile, 1H,1H,2H,2H-perfluorodecyltriethoxysilane was presented in the spraying liquid to gain the low surface energy for the surface. Additionally, the composite nanofibers played a role in mitigating the temperature polarization. A series of characterizations on membrane morphologies, wetting behaviors, structural peculiarities and stable properties were investigated systematically. The results showed that the re-entrant morphology consisted of the intersecting nanofibers was constructed skillfully, looking like the nest's hierarchical structure. The composite membrane displayed outstanding contact angles of 172.0 ± 1.8°, 170.5 ± 3.5°, 160.1 ± 2.6°, 165.0 ± 3.0°, 162.5 ± 4.5°, 151.0 ± 1.5°, 153.5 ± 3.5° and 118.0 ± 3.0° towards DI water , 3.5 wt% NaCl, 0.4 mM SDS , 0.4 mM CTAB, 0.4 mM Tween-20, ethanol, soybean milk and dodecane, respectively. The modified membrane presented a 167% LEP measurement of the pristine membrane and satisfactory chemical and thermal stabilities along with silver mirror phenomena. Furthermore, the omniphobic membrane exhibited anti-fouling and anti-wetting performances with high and stable permeate fluxes (36.3 kg/m 2 ·h) as well as a nearly 100% salt rejection rate in the consecutive DCMD tests, where HA and diverse surfactants were added to the brine feed. This suggests the omniphobic membrane as a promising alternative for wastewater treatment in membrane distillation.
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 Environmental Chemical Engineering
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2024
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IF 7.4
Chao Wang,Hongyang Li,Bixin Wu,Jianqiang Meng
ABSTRACT Membrane Aerated Biofilm Reactor (MABR) stands out as an innovative technology for wastewater treatment. However, biofilm formation poses a significant challenge in its implementation. Surface modification emerges as a viable strategy to enhance biofilm development. In this study, biofilm formation was effectively promoted by coating polydopamine (PDA) and loading aluminum oxide nanoparticles (Al 2 O 3 NPs) onto a polypropylene (PP) hollow fiber membrane, aiming to improve wettability and potential. Results from the bacterial attachment assay demonstrated a significantly higher bacterial attachment rate on the membrane loaded with Al 2 O 3 NPs compared to PDA/PP and PP membranes. A comprehensive investigation into the MABR process was conducted, assessing both short-term and long-term (72 days) performance. In the short-term process, the Al 2 O 3 NPs-PDA modified membrane exhibited superior removal efficiency for chemical oxygen demand (COD), ammonium nitrogen (NH 4 + -N), and total nitrogen (TN) compared to other membranes. Transitioning to the long-term process, the start-up period for the Al 2 O 3 NPs (10) -PDA/PP membrane was notably shortened to 27 days, surpassing the start-up times of PP and PDA/PP membranes by 13 and 5 days, respectively. Throughout the long-term operation, when the influent COD, NH 4 + -N, and TN concentrations increased, the Al 2 O 3 NPs-PDA/PP membrane consistently maintained removal efficiency above 95%, 98%, and 85% for COD, NH 4 + -N, and TN, respectively, demonstrating excellent resistance to shock loading.
研究领域:
环境工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
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2018
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IF 4.427
Chang Liu,Lin Chen,Liang Zhu
This study was carried out by applying the direct contact membrane distillation (DCMD) into the treatment of effluent from anaerobic membrane bioreactor . The treatment efficiency of DCMD was highly emphasized, which was expected to be improved through the optimization of operating conditions. Three operating conditions, including temperature difference, cross-flow velocity and membrane pore size, were considered. The relative flux (the ratio of actual flux to initial flux) increased from 0.50 to 0.98 as the operating conditions changed and that was enhanced by the increment of temperature difference and cross-flow velocity. Regarding the wastewater treatment efficiency, except for ammonia nitrogen, the interception ratio was greater than 90.0%, which even reached 99.0% for COD Cr , protein and polysaccharide by optimizing operating conditions. In addition, the interception ratio of PO 4 3- -P almost reached 100.0% under any operating condition. Further study about membrane fouling was carried out, and the crystallization fouling was found to be the main fouling type.
研究领域:
环境科学
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废水处理工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2018
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IF 6.578
Jindan Wu,Wei Wei,Shihong Li,Qi Zhong,Fu Liu,Jinhuan Zheng,Jiping Wang
The effect of membrane surface charge on demulsification and fouling resistance during emulsion separation is investigated. By grafting poly(2-dimethylaminoethyl methacrylate) (pDMAEMA) and poly(oligo(ethylene glycol) methacrylate) (pOEGMA) onto polypropylene (PP) membrane via ultraviolet (UV)-initiated polymerization, the obtained membranes PP- g -pDMAEMA and PP- g -pOEGMA present positive and negative surface charges in water, respectively. During the emulsion separation, PP- g -pOEGMA and PP- g -pDMAEMA membranes exhibit different separation efficiencies and pollutant resistant behaviors to the emulsions prepared from anionic surfactant (sodium dodecyl sulfate, SDS) and cationic surfactant (cetyltrimethylammonium bromide, CTAB). Comparing to PP- g -pOEGMA, the separation efficiency of PP- g -pDMAEMA was 15% (SDS emulsion) and 300% (CTAB emulsion) higher. But the flux recovery ratio of PP- g -pOEGMA was raised 30% (SDS emulsion) and 16% (CTAB emulsion). Hence, the membrane surface positive charges assist demulsification, but aggravate the membrane fouling . The mechanism obtained is beneficial to construct membranes with high separation efficiency and long-term durability.
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
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
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IF 7.312
Jiguang Huang,Heng Zhang,Yuntao Zhang,Dehua Liang,Haiping Chen
Water recovery from flue gas with transport membrane condenser (TMC) has gained much attention in recent years. It has great potential in water conservation and air pollution control. However, effects of porosity and pore size variation of macroporous membranes on TMC application have not been revealed. Coal fly ash (CFA) is used as main raw material to prepare various tubular macroporous ceramic membranes for TMC application. The extrusion method is adopted. Characterization of membranes are conducted for structural parameters evaluation. Prepared membranes were used for TMC application to experimentally study the water and heat recovery performance. Influences of temperatures and flowrates of flue gas and cooling water on recovery performance have been investigated. Increasing cooling water flowrate and flue gas temperature, as well as decreasing cooling water temperature can promote water and heat recovery performance of TMC. The highest water recovery efficiency is 79.21%. Although membrane pore size increasing improves water and recovery, the average pore size should be less than 2 μm to avoid transmembrane gas permeation. Results indicate that CFA membrane is suitable for TMC application and provides investment reduction.
研究领域:
环境科学
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材料科学
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化学工程
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能源工程
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膜科学与技术
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2019
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IF 5.589
Xiaotong Xu,Hanmin Zhang,Mingchuan Yu,Yuezhu Wang,Tianyu Gao,Fenglin Yang
Membrane fouling in forward osmosis (FO) significantly affects water flux and membrane life, which restricts the further development of FO. In this work, carbon nanoparticles were blended in polyethersulfone (PES) to prepare a conductive thin film nanocomposite (TFN) FO membrane to control the membrane fouling in FO processes. The membrane containing 4 wt% carbon exhibited an optimum performance with water flux of 14.0 and 17.2 LMH for FO (active layer for FS) and PRO (active layer for DS) modes, respectively, using DI water as feed solution and 1 M NaCl as draw solution and electrical conductivity of 170.1 mS/m. Dynamic antifouling experiments showed that, compared with no voltage applied, the water flux decline of surface charged TFN-FO membrane was significantly retarded. For CaSO 4 , BSA and LYS as model contaminants, the water fluxes were improved by 31%, 13% and 7% under the voltages of +1.7 V, −1.7 V and +1.7 V, respectively. Moreover, the charged membrane is more effective in relieving the initial membrane fouling, and contaminant-contaminant interactions mechanism dominates the formation of further membrane fouling processes. Therefore, for contaminants with different charge conditions, customizing membrane surface charges is a feasible and promising approach for controlling membrane fouling in situ method.
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
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DESALINATION
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2018
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IF 6.603
Hadi Attia,Daniel J. Johnson,Chris J. Wright,Nidal Hilal
A novel approach to enhance membrane performance using electrospinning fabrication technique for recovery of heavy metals using air-gap membrane distillation is described. Accordingly, a comprehensive study was accomplished to fabricate a unique electrospun dual-layer membrane (ESD) with an upper superhydrophobic layer and hydrophobic electrospun support layer and compare with a superhydrophobic electrospun single layer membrane (ESS). Superhydrophobic alumina nanoparticles (Al 2 O 3 ) were embedded in a low polymer concentration of polyvinylidene fluoride (PVDF) to produce superhydrophobic ESS and top layer of ESD using electrospinning technique , while a mat with different concentrations of PVDF were used as hydrophobic electrospun support layer. In this study, dual layer membranes were fabricated in two sets. In the first set, layer thickness was varied by changing the spinning volume of the top and support layer with maintain total spinning volume, while in the second set the fibre diameter of the support layer was varied by changing the polymer concentration. Moreover, the electrospun membranes were characterized in terms of membrane performance such as: permeate flux , heavy metal rejection and energy consumption; wettability performance such as liquid entry pressure (LEP), and water contact angle (WCA); membrane structure such as mean with maximum pore size and porosity; membrane integrity such as mechanical and thermal integrity. The heavy metal rejection was >99% for all single and dual layer membranes when filtering artificial wastewater (Pb, Cd, Cr, Cu, Ni). When compared with single layer electrospun membrane made from spinning 16 ml PVDF, dual layer membrane made from the same spinning volume exhibited some improvement, such as higher permeate flux above 23 l/m 2 ∙h (LMH) when filtering 2500 ppm concentration heavy metal feed water . Additionally, both sets of dual layer membrane demonstrated better mechanical performance and slight reduction of LEP compared with single layer electrospun membrane.
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
DESALINATION
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2014
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IF 3.96
Feng Wang,Jiuming Li,Hailin Zhu,Huapeng Zhang,Hongyan Tang,Jianyong Chen,Yuhai Guo
In order to remit the membrane wetting in membrane distillation (MD), polytetrafluoroethylene (PTFE) flat membrane with low surface free energy and high water contact angle (WCA) was prepared by a simple heat setting process. Membrane morphology evolution, such as breakage of fibrils and fusion of PTFE resin, and its influence on membrane characters including pore size, porosity and roughness were discussed. The effect of the heat setting process on the membrane wetting was evaluated by the membrane wetting time (MWT) in a static absorption experiment (SAE) and sweep gas membrane distillation (SGMD). The results show that the crystallinity decreases with increasing the heat setting temperature and time, which leads to low surface free energy and therefore low adsorbing capacity of penetrating agent and the long wetting time in the static absorption experiment and SGMD. In addition, pore size increases firstly and then decreases due to the breakage of fibrils and fusion of PTFE resin, respectively, which further affects the permeate flux . Therefore, we propose that the anti-fouling property and separation performance of PTFE flat membrane in SGMD can be well handled and hope that such a PTFE flat membrane would be potentially useful in seawater desalination .
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
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
危险品化学品经营许可证（带存储）