Journal of Environmental Chemical Engineering
·
2021
·
IF 5.909
Wanying Xie,Ji Li,Feiyun Sun,Wenyi Dong,Zijun Dong
Aiming at the fouling problem of PVDF membrane, one novel integrated strategy was used for the first time, including hydrophilic membrane modification and low-pressure operation. Permeability and anti-fouling ability of PVDF were simultaneously improved by nano-TiO 2 embedment. From perspective of operating condition optimization, the concepts of critical flux (J C ) and threshold flux (J TH ) were recommended as fouling-control tools. The J C and J TH of PVDF-TiO 2 membrane were tested by two constant pressure-steps methods, i.e. Constant pressure-step method and Alternating constant pressure-step method. Three indicators, consisting of instant FTTT curves, dFlux/dt condition and TMP-Flux ave curve, were employed to evaluate the J C and J TH of PVDF-TiO 2 membrane. In brief, the J C and J TH of PVDF-TiO 2 were 10.62 and 23.91 L/(m 2 ·h), respectively, which were nearly 3 times of PVDF membrane. Fouling resistance results displayed that protein irreversible fouling of two PVDF membranes were effectively reduced by J C mode and J TH mode. Besides, reversible fouling of PVDF-TiO 2 membrane was controlled well by J C mode meanwhile. The pure water filtration line (PWF line) and the normalized resistance were both used to judge the form of J C of two membranes. As compared with PVDF, it was speculated the enhancement of J C and J TH mainly related to the better hydrophilicity and local hydraulic condition of PVDF-TiO 2 modified membrane.
研究领域:
环境科学
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材料科学
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生物工程
✓ 已验证
产品关联
DOI
高影响因子
DESALINATION
·
2018
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IF 6.603
Jiaqi Huang,Shu Xiong,Qingwu Long,Liang Shen,Yan Wang
Proper draw solution is a crucial factor to generate a high performance in FO process. In this study, a phytic acid and its salt (PA-Na) were evaluated as novel draw solutes in FO process. The effects of the solution pH and concentration on the physicochemical properties were investigated systematically. Using 0.45 M PA-Na draw solution (pH = 7) and DI water feed solution, a relative high water flux of 19.02 LMH and a low solute flux of 0.51 gMH can be obtained, with HTI-TFC membrane in the PRO mode. An even better performance of a 30.35 LMH water flux and a 0.61 gMH solute flux can be achieved using the self-made HPAN-TFC membrane. The comparison of PA-Na and NaCl draw solutions shows that PA-Na draw solution has a much lower draw solute leakage and a competitive water flux. In addition, the application of PA-Na draw solution for the brackish water desalination was explored. The diluted PA-Na draw solution after FO may be used directly in food production by further dilution. In general, the non-toxicity and satisfactory FO performance of this food additive demonstrate its great potential as a draw solute for FO applications.
研究领域:
食品科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
Membranes
·
2022
·Vol. 12
·期 2
·146
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IF 4.562
Yuqi Nie,Chaoxin Xie,Yi Wang
The Forward Osmosis (FO) membrane was the core of FO technology. Obtaining a high water flux while maintaining a low reverse solute flux has historically been considered the gold standard for a perfect FO membrane. In a thin-film composite FO membrane, the performance of the membrane was determined not only by the material and structure of the porous support layer but also by the structural and chemical properties of the active selective layer. Researchers have selected numerous sorts of materials for the FO membranes in recent years and have produced exceptional achievements. Herein, the performance of the modified FO membrane constructed by introducing new two-dimensional nanomaterial MXene nano-sheets to the interfacial polymerization process was investigated, and the performance of these modified membranes was investigated using a variety of characterization and testing methods. The results revealed that the MXene nano-sheets played an important role in improving the performance of the FO membrane. Because of the hydrophilic features of the MXene nano-sheets, the membrane structure may be tuned within a specific concentration range, and the performance of the modified FO membrane has been significantly enhanced accordingly. The optimal membrane water flux was boosted by around 80%, while its reverse solute flux was kept to a minimum of the resultant membranes. It showed that the addition of MXene nanosheets to the active selective layer could improve the performance of the FO membrane, and this method showed promising application prospects.Keywords:forward osmosis membrane;MXene nano-sheets;water flux;reverse solute flux
研究领域:
膜科学
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纳米技术
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水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
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2017
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IF 3.387
Hao-Ran Zuo,Gui-Ping Cao,Meng Wang,Huan-Huan Zhang,Chen-Chen Song,Xu Fang,Tao Wang
Forward osmosis (FO) has received great interest for its considerable potential in a wide range of fields. In this work, the morphology and performance of FO membrane were regulated by adjusting the atmosphere humidity ( H C ) of casting procedure. The polysulfone support layer was casted under various atmosphere humidity levels ranging from 40% to 80%. By multi-techniques such as SEM, AFM, and XPS, it was proved that the atmosphere humidity had modified the surface morphology and thickness of the skin layer in support layer, which contributed up to 90% of the structure parameter, resulting in distinct morphology, thickness, and cross-linking degree of active layer. The active layer with sparse bead-like wrinkles on the smooth surface of support layer casted at H C = 65% showed the highest water permeability [26.9 (L/m 2 h MPa)] and considerable low salt permeability [0.0390 (L/m 2 h)]. It was found that the water flux of FO-65 was 27% and 46% higher than that of FO-80 in AL-DS and AL-FS mode, respectively, and the salt rejection was as high as 98%. Our work highlighted the importance of considering the effect of atmosphere humidity during casting when design an FO membrane for appropriate performance.
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
Journal of Materials Chemistry A
·
2021
·Vol. 9
·期 11
·6905-6912
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IF 12.732
Mingrui He,Panpan Wang,Runnan Zhang,Zhongyi Jiang,Xu He,Jun Ma
Stable high flux is a big challenge for oil/water separation membranes due to the adhesivity and spreadability of oil droplets. Membranes with hydrophilic modification usually have high basic flux, but suffer from a serious flux decline. Membranes with synergic hydrophilic and low-surface-energy (LSE) modification show a remarkably relieved flux decline, but at the expense of low basic flux. The LSE domains on membrane surfaces promote oil fouling release but hinder water permeation. In order to relieve the adverse side effects of LSE domains, this study focuses on the distribution of hydrophilic and LSE domains on membrane surfaces. Membranes with a fluorine island structure are prepared, in which LSE domains are discrete in sub-microscaled distribution, while hydrophilic domains are consecutive in a wide area. The diameters of oil droplets are much larger than those of water molecules; therefore, water molecules quickly permeate at consecutive hydrophilic domains, and oil droplets are still released by discrete LSE domains. The stable flux of the membranes is improved from 280 to 770 Lm−2 h−1 bar−1 just by the manipulation of domain distribution.
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
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2024
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IF 5.8
Juan Wang,Xiaoyu Wang,Yongzhao Yang,Qianlong Fu,Feng Hu,Zijian Zhang,Shuang Li
Silicon carbide (SiC) ceramic membranes are promising components for the efficient treatment of various wastewaters in membrane-based techniques. However, the high preparation temperature and then the high production cost inhibits their large-scale application. Here, an ultra-low temperature sintering process was proposed to prepare SiC ultrafiltration membrane. When the ceramic membrane was heated at 600 °C in air, a selective layer comprised of α-SiC and β-SiC formed without the emergence of crystalline silica. The thickness of the membrane layers was determined by the solid content and viscosity of the slurry. Well-dispersed SiC grains and homogeneous-distributed pores formed in the selective layers when using 100 nm SiC powders. The water flux and emulsion flux were investigated to verify the permeability of the ceramic membrane. Thus, this work proposes an energy-saving process for the preparation of SiC UF membrane and achieves the preparation of SiC UF membrane at ultra-low temperature.
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
WATER RESEARCH
·
2022
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IF 13.4
Nan Sun,Pengjia Dou,Wentao Zhai,Hailong He,Long D. Nghiem,Vahid Vatanpour,Yuebiao Zhang,Changkun Liu,Tao He
To extract lithium from salt lake brine involves a process of separation and concentration. After separating lithium from brine, the lithium ion concentration is generally a few hundred mg/L which is far below the required 20-30 g/L (as Li + ) before precipitation as lithium carbonate. The concentration step of a lithium enriched brine is crucial but highly energy-intensive. Spontaneous forward osmosis (FO) technology offers the possibility for concentrating lithium ions with low energy. Because the concentrating process involves both feed and draw solution with very high salinity, it is highly desirable to have a high performance FO membrane with a low structural parameter as well as a high rejection to ions. In this work, thin polyethylene separator supported FO (PE-FO) membranes were prepared and post-treated stepwise with benzyl alcohol (BA) and hydraulic compaction. The effect of the post-treatment on the FO performance was systematically analyzed. Excellent FO performance was achieved: the water flux and reverse salt flux selectivity were 66.3 LMH and 5.25 L/g, respectively, when the active layer is oriented towards the 0.5 M NaCl draw solution with deionized water as the feed. To the best of our knowledge, this FO flux is the highest ever reported in the open literature under similar test conditions. Applied in concentrating lithium enriched brine, the membrane showed superior water flux using saturated MgCl 2 as draw solution. A new FO model was established to simulate the water flux during the concentration process with good agreement with the experimental results. The promising results using PE-FO membrane for lithium enrichment opens a new frontier for the potential application of FO membranes.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2021
·
IF 8.742
Ke Zheng,Shaoqi Zhou,Zuqin Cheng,Guoru Huang
Quaternized poly phenylene oxide (QPPO) was synthesised and used as a modifier material to blend with polyvinyl chloride (PVC) to cast the substrate for thin-film composite (TFC) forward osmosis (FO) membranes. The addition of QPPO improved the porosity, hydrophilicity , and morphology of the substrate, thereby weakening the internal concentration polarisation of TFC membranes . Furthermore, the introduction of QPPO improved the structure of the active layer , which led to higher water permeability. Moreover, the mechanical properties of the TFC membranes were significantly improved after the introduction of QPPO. As a result, introducing QPPO significantly increased the FO performance. In addition, the TFC membrane based on a 40% QPPO blend ratio exhibited optimal FO performance: a high water flux of 71.21 L h −1 m −2 and an extremely low specific reverse solute flux of 0.079 g L −1 under the active layer facing the draw solution (DS) mode by utilising 1 M NaCl as the DS and deionised (DI) water as the feed solution; this FO performance remained fairly stable during long-term operation. This study suggests that introducing QPPO into the substrate is a sensible strategy for fabricating high-performance TFC FO membranes.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Si-ruo Chen,Ting Wang,Xinyi Zhuo,Yu-xing Wang,Li-guang Wu
Aiming to enhance permeation and anti-fouling performance of PVDF membrane, IL/PVDF and MXene-IL/PVDF mixed matrix membranes (MMMs) were fabricated by incorporating 1-hexyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide ionic liquid (IL) and MXene-IL. The microstructures of IL/PVDF and MXene-IL/PVDF MMMs were characterized by TEM, SEM, FTIR, XRD, and XPS analysis. The performance of the MMMs was evaluated in the dead-end filtration, and results showed that IL addition would increase the pore size and hydrophilicity of IL/PVDF MMMs, thereby enhancing water flux and anti-fouling performance of the MMMs. However, IL would be dissolved out from IL/PVDF MMMs during the filtration process, which would depress the flux recovery rate of the MMMs. For MXene-IL/PVDF MMMs, IL was encapsulated by intercalating into the MXene nanosheets and effectively prevented the loss of IL from Mxene-IL/PVDF MMMs in the running process. MXene-IL/PVDF MMMs had high water flux and antifouling performance, and the maximum flux recovery rate of MXene-IL co-incorporated PVDF MMMs reached 96% after four-cycle filtration, and the corresponding water flux was 129.37 L·m −2 ·h −1 . Compared with PVDF membrane, pure water flux and flux recovery rate of MXene-IL/PVDF mixed matrix membranes increased by 4.37 and 1.83 times, respectively.
研究领域:
材料科学
·
环境工程
·
膜技术
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
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IF 7.2
Dibakar Pandaya,Ming-Xiao Zhang,Zhen-Liang Xu,Tehreem Ayaz,Mahesh Kumar Joshi,Yan Zheng,Tian-Xiang Ren,Liang Cheng,Jundi Wang
Electrospun nanofiber membranes are promising support for forward osmosis (FO) composite membranes due to their high porosity and low tortuosity. However, achieving a defect-free selective layer is challenging due to the large interconnected pores of nanofiber support. In this study, the potential of polyurethane (PU)/chitosan (CS) blend nanofibrous membrane as substrate for high-performance FO membrane was investigated. PUCS blend solutions were electrospun at optimized compositions to fabricate smooth and bead free nanofibrous membranes. The resulting PUCS nanofibrous membranes exhibited superior mechanical strength compared to pristine PU due to strong interaction between PU and CS at molecular level and their spider-net-like morphology. Thermal pressing enhanced the compactness of the membrane, significantly reducing the surface roughness and thickness of the support layer. Subsequently, a polydopamine (PDA)/Fe 3 + -tannic acid (TA) interlayer was introduced to facilitate the deposition of a defect-free polyamide (PA) selective layer through the interfacial polymerization (IP) process, thereby developing a thin film composite (TFC) FO membrane. The modified PUCS-TFC membrane had water flux (J w ) rates of 35.16 LMH and 44.61 LMH with a 1 M NaCl draw solution (DS) and DI water as feed solution (FS), respectively. At the same time, it had a low reverse salt flux (J s ) of 3.364 gMH and 1.605 gMH under FO and PRO modes, respectively. The J s /J w ratio of 0.095 g/L for 1 M NaCl draw solution indicated efficient performance. The FO membrane also demonstrated an anti-fouling property when tested with humic acid. Therefore, the PUCS-TFC membrane demonstrates great potential for applications in desalination.
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
Membranes
·
2022
·Vol. 12
·期 4
·368
·
IF 4.562
Yi Wang,Yuqi Nie,Chunhong Chen,Hongjie Zhao,Ye Zhao,Yujin Jia,Jun Li,Zhanguo Li
MXene nano-sheets were introduced into a thin-film composite membrane (TFC) to reduce the mass transfer resistance (concentration polarization) and improve the membrane performance. The process entailed dissolving the MXene nano-sheets in a membrane casting solution using the blending method and introducing them into the porous support layer to prepare a modified thin-film composite forward osmosis (TFC-FO) membrane. The results showed that the water contact angle decreased by about 16%, indicating that the hydrophilicity was strengthened, and the O/N ratio of the active selective layer decreased by 13%, indicating an increased degree of crosslinking, thereby demonstrating that the introduction of MXene nano-sheets changed the properties of the membrane and played a positive role in its physicochemical properties. In contrast to the unmodified TFC-FO membrane, the modified membrane had a slightly higher reverse solute flux, while its water flux increased by about 80%. Its specific reverse osmosis flux was also significantly optimized (only 0.63 g/L). In conclusion, adding MXene nanosheets to TFC-FO membranes led to the modified membranes with better mass transfer, lessened internal concentration polarization (ICP), and better osmotic separation.Keywords:TFC-FO membrane;MXene nano-sheets;internal concentration polarization
研究领域:
材料科学
·
膜技术
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Cleaner Production
·
2023
·
IF 11.1
Miaolu He,Yushuang Li,Leihao Feng,Jiaqi Wang,Ze Liu,Lei Wang,Jin Wang,Rui Miao,Xudong Wang
The traditional thin-film composite (TFC) forward osmosis (FO) membrane has problems such as poor water permeability and low lithium concentration selectivity because the separation layer is too thick and has many defect pores. In this study, a thin and dense separation layer was obtained by constructing a sodium alginate (SA)/UiO-66-NH 2 interlayer to control the attachment amount and diffusion rate of m-phenylenediamine (MPD), which enhanced the performance of the membrane. This paper studies the effect and mechanism of the interlayer on the structure and separation performance of the FO membrane, and explores the lithium ion concentration performance of the interlayer membrane. According to the results, based on the strong interaction between the interlayer and MPD, the equilibrium concentration of MPD available for interfacial polymerization was increased and the diffusion rate of MPD was slowed, resulting in the generation of a thin and dense separation layer. Since the interlayer restricted the escape of bubbles formed in the interfacial polymerization, the separation layer showed a leaf-like structure with increased filtration area and water storage space. Due to the reduced thickness of the separation layer and its leaf-like structures, the water flux increased significantly, and the water flux of the interlayer membrane was 47.9% greater than that of the original membrane. Drawing upon the heightened density of the separation layer and secondary separation of the interlayer, the reverse solute flux was lowered by 37.4%. The interlayer membrane exhibited efficient Li + rejection (R>93%) and the concentration ratio of Li + was close to its theoretical concentration ratio at 1.46 ± 0.03.
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
危险品化学品经营许可证（带存储）