DESALINATION
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2020
·
IF 7.098
Jiayu Tian,Hailin Chang,Shanshan Gao,Ruijun Zhang
The potential toxicity of heavy metals arising from the discharge of industrial wastewater has become a serious public concern. Fabrication of a thin film composite (TFC) NF membrane with desirable rejection of heavy metal ions is an attracting route to solve this problem. Hereon, we proposed a facile strategy for fabricating a TFC NF membrane with excellent heavy metal removal. The ratio of PIP and TMC was greatly enlarged by decreasing the concentration of TMC to an exceptional low extent. Thus a polyamide film with weak electronegativity and small pore size was successfully constructed on an ultrafiltration substrate membrane. Comprehensive characterizations were adopted to reveal the micro-variation of the resulted NF membranes when regulating TMC concentration . The optimized membrane prepared only with PIP and TMC can exhibit a high pure water permeability of 14.6 L m −2 h −1 bar −1 , desirable rejection of over 98% against Ni 2+ , Zn 2+ , Cu 2+ , and >92.7% against Cd 2+ . This performance could go beyond most of the reported candidates which were prepared with other complicated methods. The simplicity, low cost and scaling up feasibility of the current strategy is expected to well meet the requirements of industrial production of TFC NF membrane for heavy metal removal.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Polymers
·
2017
·Vol. 9
·期 4
·116
·
IF 3.364
Rengui Weng,Lihui Chen,Shan Lin,Hui Zhang,Hui Wu,Kai Liu,Shilin Cao,Liulian Huang
Presently, most nanofiltration membranes are prepared with non-biodegradable petrochemical materials. This process is harmful to the ecosystem and consumes a large amount of non-renewable energy. In this study, biodegradable and biocompatible antibacterial cellulose/chitosan nanofiltration membranes (BC/CS-NFMs) were fabricated and characterized for their mechanical strength, antimicrobial activity, salt and dye filtration performance, and polyethylene glycol (PEG) retention using Thermal gravimetric analysis (TGA), Field emission scanning electron microscopy(FE-SEM), Fourier transform infrared spectroscopy(FT-IR), and X-ray diffraction (XRD). The BC/CS-NFMs were obtained by the hydrolysis and carboxymethylation of dense cellulose/chitosan membranes (BC/CSMs). The tensile strength of the BC/CS-NFMs decreased as the chitosan content increased. In addition, the thermal stability and antibacterial ability of the BC/CS-NFMs improved. The pore size is less than 1 nm, and a spongy, layered structure is observed in the cross-sectional FE-SEM images. FT-IR analysis shows that a part of the hydroxyl in cellulose transforms to carboxymethyl during the hydrolysis and carboxymethylation of the BC/CSMs. No obvious changes can be observed in the cellulose and chitosan after the blend membrane formation from the XRD measurements. Based on the experimental results on the permeation and rejection of BC/CS-NFMs, different proportions of cellulose and chitosan nanofiltration membranes almost did not affect the water flux and rejection rate. The BC/CS-NFMs showed better water flux and a higher rejection rate in aqueous dye-salt solutions.Keywords:cellulose;chitosan;antibacterial activity;nanofiltration membranes
研究领域:
材料科学
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环境科学
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生物医学
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产品关联
DOI
PubMed
高影响因子
DESALINATION
·
2023
·
IF 9.9
Qiu-Yu Zhu,Zi-Yun Xu,Jie-Han Fu,Jie Huang,Zhen-Liang Xu,Min Tong,En-Chao Li,Yong-Jian Tang
Currently, most nanofiltration membranes exhibit satisfactory separation performance on the anions or cations, and few membranes could concurrently separate anion and cation . Therefore, preparing nanofiltration membranes with excellent separation performance for both anionic and cationic ions remains a challenge. Herein, we have developed a series of nanofiltration membranes using conventional interfacial polymerization with different ratios of trimesoyl chloride (TMC) and piperazine (PIP) concentrations. In the interface polymerization process, the amine groups carried by PIP imparted a positive charge, while the hydrolysis of acyl chloride groups resulted in the generation of carboxylic acid groups that introduced a negative charge. The mix-charged nanofiltration membrane could be fabricated by varying PIP/TMC concentration ratios. The optimized membrane exhibited high rejection rates for bivalent ions (Na 2 SO 4 rejection of 96.6 %, MgCl 2 rejection of 93.0 %), and its selectivity for Mg 2+ /Li + mixed solution was improved significantly. This work provides a novel approach for the development of nanofiltration membranes capable of effectively separating mono-/divalent ions.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2021
·
IF 8.742
Ben-Qing Huang,Yong-Jian Tang,An-Ran Gao,Zuo-Xiang Zeng,Shuang-Mei Xue,Chen-Hao Ji,Chuyang Y. Tang,Zhen-Liang Xu
Heavy metals pollution is an urgent problem that seriously hazards human health and ecosystems. Herein, dually charged nanofiltration (NF) membranes were prepared via a facile modification with diethylenetriamine (DETA) after interfacial polymerization. More amine groups were imported after grafting and a polyamide layer with opposite charges was constructed. The as-prepared membranes had a pure water permeability of 17.0 L m −2 h −1 bar −1 and maintained ideal rejection for both Na 2 SO 4 (98.2%) and MgCl 2 (94.1%), illustrating dually charged property. In addition, the dually charged NF membranes had high rejection to a series of heavy metals, showing good application potential in heavy metals removal .
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
ACS Applied Materials & Interfaces
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2020
·
IF 8.758
Liang Ren,Jianxin Chen,Qing Lu,Jian Han,Hong Wu
Membrane fouling, caused by aggregation of organics and microorganisms from filtrate on the membrane surface, seriously reduces the service life of a nanofiltration (NF) membrane. Developing facile and renewable antifouling modification methods without sacrificing separation properties of the membrane remain an imperative requirement. Herein, a thin-film composite (TFC) NF membrane with a light-responsive and regenerable functional layer (P-TFC) was fabricated via host–guest interactions between the azobenzene (guest) labeled functional polymers and the β-cyclodextrin (host) bonded membrane surface (H-TFC). The P-TFC-3 not only showed outstanding antifouling ability and high flux recovery ratio (FRR > 90% at the fourth antiadhesive test) but also exhibited enhanced water permeability (17.9 L m–2 h–1 bar–1) and high selectivity (αMgSO4NaCl = 33.4 and fast antibiotics enrichment capacity) compared with the pristine membrane. Furthermore, when the functional layer was contaminated, it can be removed by ultraviolet light irradiation and a new functional layer can be rebuilt by adding fresh azobenzene labeled functional polymers. After several regeneration processes, the membranes still showed constant separation properties and high flux recovery ability (FRR > 90%). This work proposes an easy-to-assemble and regenerable surface modification strategy to endow TFC NF membranes with excellent fouling resistance and sustainable utilization ability while maintaining high separation properties.
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
DESALINATION
·
2024
·
IF 8.3
Peng Zhao,Fei Guo,Lingfeng Wang,Huange Zhen,Ning Zhang,Shaohua Yin,Guoli Zhou,Xuehua Ruan,Gaohong He,Xiaobin Jiang
Nanofiltration membranes with high selectivity and long-term stability for magnesium and lithium ions are crucial to efficiently enriching lithium resources in salt lake brines. Herein, a nano-gradient-structured nanofiltration membrane was fabricated, in which PEI with different molecular weights and TMC were utilized in a gradient interfacial polymerization process to construct the target active layer. Via this facile strategy, the grafting density of PEI and the amino group introduced were properly adjusted, and the pore size distribution and surface charge of the active layer were optimized. The fabricated active layer simultaneously possesses sub-nanometer pore size with a modified gradient structure and high interfacial positive charges, which can accurately screen lithium and magnesium. The successful grafting of secondary PEI and the high positive charge and continuity of the active layer have been demonstrated. After 150 hour operation (Mg/Li ratio of 50), PEI-70000/PA/PES nanofiltration membrane achieved a lithium‑magnesium separation factor (S Li/Mg ) as high as 150 while maintaining the stable permeation flux of approximately 20 L·m −2 ·h −1 ·MPa −1 , and the terminal Mg/Li ratio on the permeable side falls to 0.32, which exhibits significant potential for extracting Li from salt lake brines with high Mg/Li ratio with promising long-term stability.
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
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2021
·Vol. 37
·期 5
·1101-1109
·
IF 1.307
Bian Xiangying,Zhang Yuping,Gong Li,Zhu Yuzhang,Jin Jian
I mproving the permeate flux but retaining the rejection of thin-film composite(TFC) polyamide nanofiltration(NF) membrane is a high requirement for desalination. In this work, a calcium ion(Ca 2+ ) coordinated polyamide(PA) NF membrane was prepared by directly adding CaCl 2 to the piperazine(PIP) aqueous solution during the interfacial polymerization process. Due to the coordination interaction between Ca 2+ and the amide bond in PA active layer, the number of hydrogen bonds in the PA active layer was reduced, causing in turn the decrease of physical cross-linking degree. As a consequence, the pore of the PA active layer was enlarged, prominently enhancing the water permeance of NF membrane. With the increase of CaCl 2 concentration, the pure water flux of TFC NF increased significantly while the rejection of Na 2 SO 4 decreased sightly. Compared with TFC NF membrane prepared without CaCl 2 , the permeate flux of the Ca 2+ coordinated polyamide NF membrane prepared under optimal conditions was increased by 3–4 folds with Na 2 SO 4 rejection of 95.26%. Meanwhile, such a Ca 2+ coordinated PA NF membrane showed a better SO 4 2− /Cl − selectivity.
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
ACS ES&T Water
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2020
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IF 0
Huihui Zhao,Linyan Yang,Xueming Chen,Lankun Cai,Yejin Li,Mei Sheng,Guomin Cao,Qianhong She
The co-presence of haloacetic acids (HAAs) and Mg2+ in swimming pool waters and the potential interaction among Mg2+, HAAs, and membranes prompted a systematic investigation of membrane performance affected by Mg2+. The rejection behavior of the tight NF90 was not significantly affected by Mg2+ due to the predominant role of size exclusion. For loose NF270, HAA rejection and water flux were reduced by 27% and 12%, respectively, after the addition of 5 mM Mg2+. The notable magnesium content in NF270 exposed in Mg2+ indicated the binding of Mg2+ to membranes. The interaction between Mg2+ and membranes resulted in a less negatively charged and hydrophilic surface and a smaller effective pore radius for membranes. The reduction of the effective pore size by Mg2+ was verified as a result of competing effects between “-COO–-induced conformational change” and “cation-induced pore shielding”. The increased permeability for charged HAAs and NaCl in the presence of Mg2+ was mainly attributed to charge neutralization, while the reduced permeability for neutral surrogates and water was due to the reduced effective pore size and hydrophilicity. The underlying mechanism for resolving the interaction among different divalent cations, trace contaminants, and polyamide membranes may have significant implications for practical water purification by membrane technologies.
研究领域:
环境科学
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膜技术
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水处理工程
✓ 已验证
产品关联
DOI
JOURNAL OF MEMBRANE SCIENCE
·
2015
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IF 5.056
Shu Zhu,Song Zhao,Zhi Wang,Xinxia Tian,Mengqi Shi,Jixiao Wang,Shichang Wang
In this work, non-woven fabric supported polyetersulfone (PES)/polyaniline (PANI) blended membranes were fabricated by immersion precipitation process and used as the substrates for thin-film composite (TFC) membranes. Polyamide (PA) TFC nanofiltration membrane was then prepared via interfacial polymerization of piperazine (PIP) in water with trimesoyl chloride (TMC) in hexane over PES and PES/PANI substrates. The prepared substrates and TFC nanofiltration membranes were characterized with respect to chemical structure , morphology and separation performance. The influence of substrate properties on the PA layer was investigated and discussed. It is evident from the results that the differences in substrate properties affect the diffusion and reaction of the monomers during interfacial polymerization process, leading to the changes in the thickness and cross-linking degree of the PA layer. Compared to PES substrate, the PES/PANI substrate comprising 0.2 wt% of PANI could greatly enhance flux and salt rejection of TFC nanofiltration membrane.
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
DESALINATION
·
2022
·
IF 11.211
Xiumin Zhang,Yongping Dong,Qingyi Wang,Hang Yu,Congjie Gao,Lixin Xue
Structures and NF performance of TFC-Co and TFC membranes activated with 50 % alcohol solutions were studied. Methanol and glycol solution activation increased water flux 2–4 times without trading off salt rejection while glycerin solution activation increased water flux 3–4 times with reduced salt rejection and increased dye/salt retention selectivity . The Stokes radius of TFC-Co membrane changed from 0.77 nm to 0.66, 0.78 and 0.92 nm while the TFC membrane changed from 0.54 nm to 0.55, 0.65 and 0.70 nm after activation with methanol, glycol and glycerin solutions, respectively. Capillary pore filling models were developed from pure alcohol absorption experiments including the stages of initial pore filling, pore expansion, pore relaxation and pore adjustment, while most Stokes radius after 50 % solutions activation were found to be close to the relaxed pore radius values (r rx ) or half of the expanded pore radius values (r ex ) from pure alcohol absorption experiments.
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
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Shiyu Zhang,Runnan Zhang,Runlai Li,Zixuan Zhang,Yafei Li,Hao Deng,Junhui Zhao,Tianrun Gu,Mengying Long,Xiaoyao Wang,Sui Zhang,Zhongyi Jiang
Positively charged nanofiltration membranes hold great potential in Li + /Mg 2+ separation, but their application in alkaline solutions, such as alkaline salt-lake brines has not been reported. Herein, inspired by the arginine's unique structure and biological function, we explore superstrong basic triaminoguanidine (TG) molecule as aqueous monomer to fabricate positively charged polyamide nanofiltration membranes for Li + /Mg 2+ separation. With the Li + /Mg 2+ mass ratios of 1:50 and 1:120, at pH 9.6, the separation factors (S Li,Mg ) of membranes reach 31.8 and 20.9. Meanwhile, at pH 5.6, the S Li,Mg are 46.4 and 36.4, which are the ever-reported highest value and such high S Li,Mg can be well retained in the pH range of 5.6–8.6. The superior Li + /Mg 2+ selectivity stems from the superhigh protonation capacity of guanidine groups in a broad pH range.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2023
·
IF 9.5
Lei Zhang,Mengyang Hu,Yujun Zhang,Jian Hou,Meizhi Zhang,Chang Gao,Wenming Fu,Hongsen Hui,Quan Liu,Huiying Ding,Zuhui Qin,Hongchang Pei,Hideto Matsuyama
To balance the permeability-selectivity trade-off effect of the polyamide nanofiltration membrane, interfacial polymerization regulation strategy is widely used to optimize the physicochemical structure of the polyamide film. In the present work, the compound additives of phytic acid and ferric chloride were added into the aqueous phase to regulate the interfacial polymerization process. On the one hand, a lot of piperazine monomers will be adsorbed around the phytic acid molecules due to the electrostatic interaction between phosphoric acid groups and amino groups. Meanwhile, the phytic acid molecules and ferric ions can form a complex in the piperazine solution, which results in a low diffusion rate of the other piperazine monomers without adsorbed on the phytic acid and ferric chloride complex due to steric hindrance. The synergistic effect of electrostatic interaction and steric hindrance leads to the optimized nanofiltration membrane with a thinner and looser polyamide structure. The best-performing nanofiltration membrane exhibits an approximately four-fold water permeance (28.4 L m −2 h −1 bar −1 ) compared with the controlled M0 nanofiltration membrane (6.5 L m −2 h −1 bar −1 ) without obviously sacrificing the Na 2 SO 4 rejection (96.9 %). This simple interfacial polymerization regulation strategy provides a novel insight for the preparation of high-performance NF membrane.
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