JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 9
·49939
·
IF 2.52
Ke Zheng,Shaoqi Zhou,Zuqin Cheng,Guoru Huang
Synthesized by the reaction between α-cellulose and m-tolyl isocyanate (MTI), cellulose carbamate (CC) was blended with polyvinyl chloride (PVC) to fabricate substrates for thin-film composite (TFC) forward osmosis (FO) membranes. The introduction of CC into substrates improved both membrane structure and performance. The substrates exhibited higher porosity and hydrophilicity, and better connective pore structure; while rejection layer exhibited better morphology but limited cross-linked degree decrease after the introduction of CC. According to the results, the CC blend ratio of 10% was the optimal ratio. With this blend ratio, the TFC-10 membrane presented favorable water permeability (1.86 LMH/bar) and structure parameter (337 μm), which resulted in excellent FO performance (water flux with a value of 40.40 LMH and specific salt flux with a value of 0.099 g/L under rejection layer faces draw solution [DS] mode when 1 M NaCl and deionized water were utilized as DS and feed solution). In addition, the TFC-10 membrane showed good water flux and low-sulfate ion leakage in the potential application of brackish water desalination.
研究领域:
材料科学
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环境工程
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水处理
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产品关联
DOI
高影响因子
DESALINATION
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2025
·
IF 9.8
Junliang Dong,Song Su,Qianzhi Sun,Ran Yu,Longyi Lv,Ruijun Zhang
Nanofiltration (NF) is a promising technology for brackish water desalination due to its tunable separation efficiency and effective removal of organic contaminants. However, the limited diversity of commercial NF membranes hinders optimal performance. To address this, we developed a tailored NF membrane by simultaneously increasing the piperazine (PIP) concentration and decreasing the trimesoyl chloride (TMC) concentration aiming for the treatment of a typical sulfate-type brackish water. The optimized membrane demonstrated superior performance: adequate desalination capability and improved anti-fouling properties. In particular, the NF membrane fabricated with 1.5 %( w / v ) PIP and 0.03 %(w/v) TMC exhibited a more compact polyamide structure and superior desalination performance compared to NF270. In comparison to NF90, it presented greater surface hydrophilicity (~40°) and nearly two-fold higher permeation flux. Moreover, it exhibited significantly improved anti-fouling ability, as evidenced by its 99.9 % flux recovery versus NF90's 23.5 % after brine cleaning. This enhancement is attributed to its optimized solute selectivity and surface chemistry, which reduce concentration polarization and foulant adhesion. Our work provides a practical and feasible strategy for customizing NF membrane structures to improve desalination efficiency and sustainability.
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
·
2023
·
IF 9.5
Qiang Xue,Wenqiao Meng,Jinyuan Zhu,Qing Fang,Kaisong Zhang
Constructing nanomaterials interlayer for high-performance polyamide membranes is a popular technique in brackish water desalination, while selecting a suitable nanomaterial and convenient method for constructing interlayer remains a challenge. Herein, easily-modified MXene nanosheets were carboxylated to obtain excellent hydrophilicity, negative charge, and good compatibility with polymer, which were applied to construct carboxylated MXene (COOH-MXene) interlayered polyamide membranes by facile brushing process. COOH-MXene nanosheets have good compatibility with polyamide and supporting membranes, and make the membrane surface wrinkled, hydrophilic and negatively charged. The optimized membrane achieves a water flux of 12.9 Lm −2 h −1 bar −1 , 2.9 times of the blank membrane. The MgSO 4 rejection is improved to 99.1%, and the NaCl rejection is only 11.4%, displaying excellent selectivity for monovalent and divalent ions. Moreover, the prepared membranes have good antifouling properties and long-lasting desalination performance. This study presents a new approach to brackish water desalination by constructing COOH-MXene interlayered membranes.
研究领域:
材料科学
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环境工程
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水处理
✓ 已验证
产品关联
DOI
高影响因子
Membranes
·
2022
·Vol. 13
·期 1
·38
·
IF 4.562
Xuebai Guo,Cuixia Liu,Bin Feng,Yuanfeng Hao
In northwest China, the limited amount of water resources are classified mostly as brackish water. Nanofiltration is a widely applied desalination technology used for brackish water treatment; however, membrane fouling restricts its application. Herein, we modified the membrane with triethanolamine (TEOA) and optimized the operating conditions (transmembrane pressure, temperature, and crossflow velocity) to control the nanofiltration membrane fouling by brackish water. Based on the physiochemical characteristics and desalination performance of the prepared membranes, the membrane modified with 2% TEOA (MPCM2) was identified as the optimal membrane, and 0.5 MPa, 25 °C, and 7 cm/s were identified as the optimal operating conditions through a series of nanofiltration experiments. Moreover, the membrane cleaning procedure for fouled MPCM2 was further determined, and a two-step cleaning procedure using ethylene diamine tetraacetic acid disodium followed by HCl with a permeance recovery rate of 98.77% was identified as the optimal cleaning procedure. Furthermore, the characterizations of the fouled and cleaned MPCM2 showed that the optimized cleaning procedure could recover the properties of MPCM2 to near virgin. This study is of great significance for the long-term stable operation of nanofiltration processes in brackish water treatment to ensure the supply of healthy water in the water-deficient areas of northwest China.Keywords:modified nanofiltration membrane;membrane fouling;brackish water;operation condition;cleaning procedure
研究领域:
环境工程
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水处理
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膜技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
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2024
·
IF 0
Liu Yucheng,Zhu Mengke,Ji Xinghu,Tan Zhiyou,He Zhike
The reverse osmosis (RO) technique has been extensively employed in the advanced treatment of industrial water and wastewater. However, this process results in the production of a significant quantity of reverse osmosis concentrate (ROC), which contains high levels of salinity and organic contaminants, thereby posing serious environmental problems. This study reported a two-stage precipitation process utilizing quicklime (CaO) and caustic soda (NaOH) in conjunction with air blowing (carbonation) for the removal of Ca 2+ and Mg 2+ from real brackish water ROC of factory. In stage I, the CaO precipitation-carbonation process was employed to eliminate the majority of Ca 2+ from the ROC, while leaving Mg 2+ virtually unaffected, yielding high-purity CaCO 3 precipitates. In stage II, the NaOH precipitation method was utilized to eliminate the remaining Ca 2+ and Mg 2+ from the ROC. It was demonstrated that under optimal conditions, the removal rates of Ca 2+ and Mg 2+ exceeded 97%. Finally, the characterization of precipitates demonstrated the generation of high-purity CaCO 3 precipitates in stage I, as well as the formation of CaCO 3 and Mg(OH) 2 precipitates in stage II. The results confirmed the feasibility of employing the two-stage precipitation with carbonation process to economically treat ROC and enable its reuse, offering valuable insights for the treatment of industrial wastewater.
研究领域:
环境工程
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水处理
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废水管理
✓ 已验证
DOI
PubMed
Journal of Materials Chemistry A
·
2017
·Vol. 5
·期 26
·13730-13739
·
IF 8.867
Junfeng Zheng,Meng Li,Yujian Yao,Xuan Zhang,Lianjun Wang
Zwitterionization of multiwalled carbon nanotubes (ZCNTs) is initially conducted by grafting poly(4-styrenesulfonic acid) and poly(4-vinylpyridine) copolymers via an atom transfer radical polymerization (ATRP) reaction, and the products obtained are further used as an aqueous additive to fabricate thin-film nanocomposite (TFN) nanofiltration (NF) membranes. The most optimal membrane with a ZCNT dosage of 0.01%, Z-TFN 0.01% shows nearly 31% enhancement in water permeability (14.9 ± 0.5 L m−2 h−1 bar−1), probably due to the shortened ZCNT, which could create a larger number of inorganic–organic interfaces in the barrier layers. Besides, it also exhibits MgSO4/NaCl selectivity (5.6 ± 0.8), 2.8 times higher than that of the pristine one (2.0 ± 0.2), which is attributed to the formation of ion-response channels and the stretching effect of the side chains. By using model brackish water as the feed solution and subjecting it to a two-stage NF process, the outstanding separation ability of the Z-TFN 0.01% membrane for the ions with the final Na+/Mg2+ concentration ratio in the permeate reaching as high as 589.2, as against only 111.7 for the control, is displayed. Furthermore, due to the strong bacteriostasis ability of quaternary ammonium compounds, Z-TFN 0.01% also shows excellent antibacterial properties, as evidenced by the mortality of Escherichia coli to 97% after remaining in contact with the membrane surface.
研究领域:
材料科学
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环境工程
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膜分离技术
✓ 已验证
产品关联
DOI
高影响因子
Engineering
·
2025
·
IF 11.6
Yu-Xuan Sun,Zhen-Yuan Wang,Liu-Yong Zhao,Rui-Hao Liu,Wu-Cong Wang,Mei-Ling Liu,Shi-Peng Sun,Weihong Xing
Rising freshwater scarcity in arid regions requires advanced desalination and resource recovery technologies to address brackish water threats to agriculture, drinking water, and ecosystems. Charge-asymmetric Janus nanofiltration (NF) membranes demonstrate significant potential for resource recovery in brackish water treatment, particularly enabling efficient ion-selective separation. However, current models remain limited to qualitative speculation regarding the ion transport mechanisms in Janus membranes, as they fail to incorporate quantitative descriptions of axial charge heterogeneity. Herein, we address this gap by integrating axial charge distribution into the Donnan Steric Pore Model with Dielectric Exclusion (DSPM-DE). A charge-asymmetric Janus membrane (R90-AC) was fabricated by coating a positively charged polyelectrolyte layer onto a commercial NF membrane (R90-SC). The axial-charge-distributed DSPM-DE model reduced prediction deviations for six ions in brackish water systems to < 8%, outperforming conventional models (deviations > 16%). Theoretical simulations revealed an intrinsic electric field (18.87 mV·μm −1 ) within Janus structures, driving anomalous electromigration contributions exceeding 100% for cations and −50% to −20% for anions. This “electrostatic diode” effect was experimentally validated, with Mg 2+ forward flux (2.69 × 10 −2 mol·m −2 ·h −1 ) surpassing reverse flux (2.98 × 10 −3 mol·m −2 ·h −1 ) by nearly an order of magnitude. The study bridges theoretical modeling and practical structure design, offering a robust framework for tailoring charge-asymmetric structures in ion-selective separations.
研究领域:
膜科学
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环境工程
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化学工程
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材料科学
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电化学
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水处理技术
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-13
·
IF 14.7
Liang Mingxing,Ren Yifan,Cui Jun,Zhang Xiaochen,Xing Siyang,Lei Jingjing,He Mengyao,Xie Haijiao,Deng Libo,Yu Fei,Ma Jie
Carbon materials with defect-rich structure are highly demanded for various electrochemical scenes, but encountering a conflict with the deteriorative intrinsic conductivity. Herein, we build a highway-mediated nanoarchitecture that consists of the ordered pseudographitic nanodomains among disordered highly nitrogen-doped segments through a supramolecular self-assembly strategy. The “order-in-disorder” nanosheet-like carbon obtained at 800 °C (O/D NSLC-800) achieves a tradeoff with high defect degree (21.9 at% of doped nitrogen) and compensated electrical conductivity simultaneously. As expected, symmetrical O/D NSLC-800 electrodes exhibit superior capacitive deionization (CDI) performance, including brackish water desalination (≈82 mg NaCl g −1 at a cell voltage of 1.6 V in a 1000 mg L −1 NaCl solution) and reusage of actual refining circulating cooling water, outperforming most of the reported state-of-the-art CDI electrodes. The implanted pseudographitic nanodomains lower the resistance and activation energy of charge transfer, which motivates the synergy of hosting sites of multiple nitrogen configurations. Our findings shed light on electrically conductive nanoarchitecture design of defect-rich materials for advanced electrochemical applications based on molecular-level modulation.
研究领域:
材料科学
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电化学
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纳米技术
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环境工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2023
·
IF 8.9
Xiang Wan,Yanyan Zhao,Xiaoguang Xu,Zongrui Li,Liqiang Xie,Guoxiang Wang,Fei Yang
The presence of microplastics (MPs) in eutrophic waters (both freshwaters and coastal waters) is increasingly reported globally, as has the occurrence of cyanotoxins, including microcystins (MCs). MPs have the potential to act as vectors for MCs in freshwater environments , but the transportation mechanisms and associated risks remain poorly understood. In this study, we investigated how aging process and water conditions influenced the adsorption behavior of the microcystin-leucine-arginine (MC-LR) onto polyethylene (PE) and polypropylene (PP). Adsorption kinetics and isotherms showed that the MC-LR sorption capacity in descending order was aged PP > pristine PP > aged PE > pristine PE. The aging process increased the MC-LR sorption amount by 25.1% and 6.5% for PP and PE, respectively. The increase in sorption affinity of aged MPs may be attributed to the significant surface oxidation and the formation of the hydrogen bonding between MPs and MC-LR. Furthermore, MC-LR sorption can be largely influenced by the aqueous conditions. MC-LR preferred to be much adsorbed onto different MPs in brackish water than in freshwater owing to the cation bridging effect and complexation of high levels of cations. The usual alkalescent pH in eutrophic waters did not favor MC-LR sorption to MPs. Finally, based on the desorption results, assuming a worst-case scenario, MC-LR bound on MPs may have a high risk to daphnids. The findings obtained in this study have improved our knowledge in the interaction of MPs with hydrophilic cyanotoxins in aqueous ecosystems, as well as the risks associated with their coexistence.
研究领域:
环境科学
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毒理学
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水生生态学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
·
IF 9
Ying-Lin He,Zhuo Chen,Dilibinuer Niyazimaimaiti,Yuan Fan,Rimeh Ismail,Abudukeremu Kadier,Chantaraporn Phalakornkule,Putu Teta Prihartini Aryanti,Ghizlane Achagri,Peng-Cheng Ma
To address global freshwater scarcity, developing a sustainable and efficient brackish/high salinity water desalination technology is crucial. Solar-driven interfacial evaporation (SIE) systems typically consist of a water-absorbing layer drawing water via capillary action to the interface and a photothermal conversion layer absorbing sunlight to heat the interface. Researchers have focused primarily on designing various photothermal materials to enhance heat generation and evaporation efficiency, while they often overlook the need for all-weather functionality, limiting further advancement of SIE systems. This study introduces a novel basalt fabric-based photo-electrothermal interfacial evaporator for all-weather efficient desalination, integrating photothermal and electrothermal effects to enhance evaporation rates and reduce reliance on sunlight. The basalt fabric is functionalized with polydopamine, carbon nanotubes, and polypyrrole to improve its photothermal properties, and stainless steel mesh 304 is used as an electrothermal layer. Under simulated sunlight (1 sun) and 1.5 V in the laboratory, the evaporation rate of actual brackish water can reach 4.43 kg m −2 h −1 ; under real sunlight and 1.5 V outdoors, the evaporation rate can reach up to 6.37 kg m −2 h −1 . Additionally, due to the well-designed multilayer structure with Janus hydrophilicity gradient distribution, the evaporator exhibits excellent salt resistance and long-term stability, maintaining a daytime evaporation rate above 2.17 kg m −2 h −1 during 120-hour continuous operation without any intervention. The purified water meets the drinking water standards set by the WHO, with significant reductions in ion concentrations and chemical oxygen demand. This study provides a promising approach for efficient and sustainable brackish water purification, offering potential applications in water-scarce regions.
研究领域:
环境科学
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材料工程
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海水淡化
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可再生能源
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可持续技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2020
·
IF 7.183
Lu Elfa Peng,Zhikan Yao,Jixuan Chen,Hao Guo,Chuyang Y. Tang
We report a novel forward osmosis (FO) membrane prepared by a green tannic acid/iron (TA/Fe) coordination chemistry to selectively separate and recover organic source from salty water. The microscopic and x-ray photoelectron spectroscopy (XPS) characterizations confirmed the formation of a thin continuous TA/Fe rejection layer with a thickness of 20–30 nm on a polyacrylonitrile (PAN) substrate. This TA/Fe-PAN membrane showed a high water permeability ( A ) of 14.2 ± 1.7 Lm −2 h −1 bar −1 , a high rejection of 99.5 ± 0.1% for a low-molecular dye sunset yellow and low rejection of 27.6 ± 2.7% for NaCl under reverse osmosis (RO) mode. The membrane selectivity to sunset yellow was nearly three orders of magnitude greater than that of NaCl, revealing its preference towards organic dye retention and salt passage. As a result of its higher water permeability and the prevention of salt accumulation during FO tests, the TA/Fe-PAN membrane showed significantly higher FO water flux compared to that of a commercially available polyamide thin film composite membrane . It could concentrate sunset yellow from a salty FS solution with a concentration ratio of 9.6 and mild salt accumulation at the water recovery ratio of 90%. The results demonstrated the feasibility of selective separation and resource recovery for target solutes from salty even more complicated water matrix via proper membrane chemistry design in FO.
研究领域:
环境科学
·
化学工程
·
材料科学
·
水处理
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2023
·
IF 11.4
Shirong Li,Langming Bai,Junwen Ding,Zihan Liu,Guibai Li,Heng Liang
Utilizing brackish water resources has imposed a high requirement on the design and construction of nanofiltration membranes. To overcome the limitation of high salt concentration on the nanofiltration separation performance resulting from the weakened Donnan effect, a nanofiltration membrane with the effect of salt-responsive ion valves was developed by incorporating zwitterionic nanospheres into the polyamide layer (PA-ZNs). The interaction between the nanospheres and membranes at high salinity was revealed through a combination analysis from the perspectives of water transport model, positron annihilation spectroscopy, and solute rejection, contributing to the formation of the valve effect. The PA-ZNs membrane presented a breakthrough in overcoming the limitation of increased salt concentrations on nanofiltration separation performance, achieving a high selectivity of 105 for mono/multivalent anions. To reveal the role of the ion valve effect in ion transport through the membrane, the membrane conductance was determined at different salt concentrations, confirming channel-controlled transport at low salinity and ion valve-controlled transport at high salinity. Moreover, the main membrane separation mechanisms were systematically studied. The concept of salt-responsive ion valves may contribute to expanding the application of nanofiltration in brackish water treatment.
研究领域:
环境科学
·
水处理
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材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）