DESALINATION
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2024
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IF 8.3
Zhongsen Yan,Ziyue Zhang,Yaman Huang,Haiqing Chang,Dan Qu,Yuling Jiang,Hongting Wan,Senlin Shao,Fangshu Qu
Membrane scaling and subsequent membrane wetting pose significant impediments to the application of membrane distillation (MD) in treating high-salinity wastewater. This study introduces an innovative in-situ bubble cleaning strategy for the amelioration of membrane scaling in MD processes. A catalytic membrane was fabricated by introducing MnO 2 as a catalyst by electrospinning and the self-cleaning mechanism involving micro-nano bubbles and superhydrophobic surface was systematically investigated. Results showed that the fabricated MnO 2 /PVDF nanofiber membranes (M-FMP) showed superhydrophobic properties, with a water contact angle and rolling angle of 158° and 17°, which significantly improved the membrane's resistance to wetting and fouling. The M-FMP membrane exhibited exceptional performance across ten experimental cycles, achieving a flux recovery rate of over 92 % and demonstrating robust chemical stability following repeated cleanings with 0.006 wt% H 2 O 2 . Notably, CaSO 4 deposition on the M-FMP membrane was approximately 46.0 μg/cm 2 , accounting for only 14.6 % of the deposition observed on the M-P electrospun membrane. The in-situ cleaning process leveraging micro-nano bubbles proved to be significantly more effective than conventional ex-situ cleaning methods, offering superior performance in removing scale deposits. Overall, this pioneering in-situ catalytic self-cleaning approach offers a new option for controlling MD membrane scaling.
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
JOURNAL OF MEMBRANE SCIENCE
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2020
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IF 7.183
Zhigao Zhu,Wei Wang,Qianyun Zhang,Xuemei Chen
The primary problem with membrane distillation (MD) for concentrating hypersaline wastewaters is its severe membrane scaling induced by increasing salt concentration of wastewater. Herein, we developed a superhydrophobic and welded-pore polyimide fibrous membranes (SH-welded PI FM) combined with optimizing feed/permeate flow velocity to alleviate membrane scaling and improve membrane water flux simultaneously. The experiments reveal that the SH-welded PI FM functionalized with welding pores avoids membrane pore deformation induced by increasing flow velocity and superhydrophobicity reduces the overall adhesive interaction between crystal and membrane surface to against membrane scaling. Comparative experiments and simulation results reveal that increasing flow velocity is also beneficial for vapor transmission by partially overcoming membrane temperature and concentration polarization and alleviating membrane scaling by producing asymmetrical disturbation on membrane two surfaces. However, the progressive increase will aggravate membrane scaling because of the excessive disturbance of flow velocity to fibers enlarging membrane pores. Therefore, designing welded-pore and superhydrophobic fibrous membrane combined with optimizing flow velocity is extraordinarily effective in simultaneously improving membrane water flux and mitigating membrane scaling for concentrating hypersaline wastewaters. These findings are significant to break the trade-off of membrane water flux and scaling for MD to concentrate hypersaline wastewaters for practical application in industries.
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 MEMBRANE SCIENCE
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2022
·
IF 10.53
Wulin Yang,Li Long,Hao Guo,Chenyue Wu,Shenghua Zhou,Ying Mei,Lu Elfa Peng,Wenyu Liu,Zhe Yang,Wanbin Li,Chuyang Y. Tang
Groundwater remediation by nanofiltration (NF) membrane is still hindered by low water recovery due to membrane scaling. In this study, a simple NaOH-promoted interfacial polymerization strategy was proposed to tailor the membrane asymmetric selectivity of calcium over sulfate ions to reduce scaling potential towards high water recovery. A 0.5 wt% NaOH was introduced during the interfacial polymerization of piperazine (PIP) and trimesoyl chloride on a polysulfone support. The promoted interfacial polymerization reduced polyamide defects for better rejection and enabled the use of lower PIP concentrations. Enhanced hydrolysis of the polyamide layer created a more negatively charged surface with larger pore sizes to achieve asymmetrical selectivity together with enhanced permeance. The water permeance of fabricated TFC-0.1 membrane with the aid of NaOH was 2.1 times that of commercial NF270 membrane, while exhibiting comparable perfluorooctanesulfonic acid rejections (>95%). This membrane also achieved ∼50% more water recovery than that of NF270 membrane under simulated gypsum scaling condition, owing to the selective passage of calcium (low rejection of 11.4 ± 0.6%). The exemplified strategy of NaOH-promoted interfacial polymerization is facile and readily scalable, which demonstrated strong potential towards high water recovery in groundwater remediation contaminated by emerging pollutants.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
DESALINATION
·
2024
·
IF 8.3
Jinjin Jia,Jinlong Wang,Dachao Lin,Jing Zhao,Hesong Wang,Longfeng Hu,Jiaxuan Yang,Han Zhang,Guibai Li,Heng Liang
Membrane scaling severely hinders practical application of nanofiltration (NF) for brackish water treatment. However, the contributions of residual aluminum ( Al ), especially various species with differing polymerization degrees and sizes, to gypsum scaling remain unclear. Herein, the complex interactions between three Al species (AlCl 3 , Al 13 and Al 30 ) and gypsum scaling were investigated, including surface and bulk crystallization processes. Results demonstrated that Al species adhering to the membrane surface promoted surface crystallization and altered crystal morphology. Notably, the Al 13 species induced the formation of dense, complete rosette crystals causing the most severe flux decline. For bulk crystallization, Al 30 was the primary species to promote nucleation. This promotion resulted from two factors: a lower nucleation energy barrier and the promoted aggregation of small crystals. Furthermore, molecular dynamics (MD) simulations revealed that the inhibition of nucleation due to the competition between Al species and calcium ions at nucleation sites was negligible compared to the strong promotion effect. These findings demonstrated that PACl exhibit higher scaling potential during NF than monomeric Al coagulants. Ultimately, the competition between surface and bulk crystallization determined the final membrane flux decline. This study offers valuable insights into the mechanisms of NF scaling caused by residual Al and guides mitigation strategies.
研究领域:
环境科学
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水处理
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膜技术
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材料科学
✓ 已验证
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
Heming Wang,Xueyong Song,Huihui Zhang,Pan Tan,Fanxin Kong
An ion exchange membrane (IEM) is an important component in dual-chamber microbial fuel cells (MFCs) to separate cathodic chromium from anode bacteria to avoid toxicity. Common used IEMs (e.g., BPM, CEM, PEM, AEM) have different ionic transfer abilities which could influence MFC performance and chromium removal. Additionally, to distinguish chromium “removal” or “reduction” by MFCs, the chromium removal in this study was further analyzed into cathodic reduction, adsorption on the membrane and permeation through membrane to the anode chamber. It was found that BPM achieved the best performance in removing hexavalent chromium (99.4 ± 0.2 %) and balancing pH and conductivity in both chambers, followed by AEM (97.9 ± 0.8 %) and CEM (95.6 ± 0.8 %), while PEM can not well maintain pH and conductivity leading to the worst anode performance and lowest chromium removal efficiency. However, the adsorption of chromium on the AEM accounts for 91.1 ± 0.7 %, which was much higher than the other three membranes. The permeation of chromium through the membrane were all lower than 0.2% which can be ignored. SEM and EDS results showed that chromium deposits and bacteria were detected on the membrane facing cahtode and anode, respectively, indicating that membrane scaling and fouling were inevitable and happened within 24 h operation.
研究领域:
环境工程
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化学工程
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电化学
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水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DESALINATION
·
2022
·
IF 11.211
Bing Zhang,Jing Shen,Heli Tang,Yu Shen,Jiansheng Li,Zhigao Zhu
Membrane distillation (MD) that can sustainably recover freshwater until salt crystallization is a potential candidate for hypersaline wastewater treatment. However, a huge challenge for MD is membrane scaling, which sharply decreases membrane flux and salts rejection efficiency. This study reported an ion-nucleating competition cooperated with commercial antiscalants to mitigate membrane scaling. Results showed that the superhydrophobic PVDF (SH-PVDF) membrane could effectively delay the gypsum nucleation on the slippery membrane surface owing to the increased membrane surface roughness, but scaling inevitably occurs on the membrane surface in the supersaturated condition. Introducing the foreign ions such as one-component Na + or Mg 2+ and two-component Na + /Mg 2+ mixture can improve the gypsum solubility and delay gypsum nucleation for mitigating membrane scaling. Besides, the synergistic combination of commercial antiscalant and ion-nucleating competition is extraordinarily effective in retarding membrane scaling and preventing membrane pore wetting, achieving a high-water recovery of ~85 % and robust salt rejection of ~100 %. The mechanisms of ion-nucleating competition cooperated with antiscalants were also discussed with the help of characterizations. This work provided a novel ion-nucleating competition in collaboration with antiscalants for hypersaline wastewater management, which is important for MD to be applied in near-zero liquid discharge (ZLD).
研究领域:
环境工程
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水处理
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膜技术
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海水淡化
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废水管理
✓ 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）