• Membrane Journal
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• v.31 no.1
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• pp.35-51
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• 2021

Advancements in thin-film nanocomposite (TFN) membrane technology for nanofiltration is crucial for removing pollutants from natural resources. In recent years, various metal-organic framework (MOF) modifications have been tested to overcome the drawbacks that are inevitable with conventional thin-film composite (TFC) and TFN membranes. In general, MIL-101(Cr), UiO-66, ZIF-8, and HKUST-1 [Cu3(BCT2)] are MOFs that were proven to exhibit excellent membrane performance in terms of solvent permeability and solute rejection; their respective studies are reviewed in this article. Other novelties, such as the simultaneous use of different MOFs and unique MOF layering techniques (e.g., dip-coating, spray pre-disposition, Langmuir-Schaefer film, etc.) are also discussed as they present alternate solutions for membrane enhancement and/or preparation convenience. Not only are these MOF-modified TFN membranes frequently shown to improve separation performance from their respective TFC and TFN membranes, but many reports also explain their potential for a cost-effective and environmentally friendly process. In this review the thin film nanocomposite nanofiltration membrane is discussed.

• Membrane Journal
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• v.16 no.2
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• pp.123-132
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• 2006

The PTMSP-silica-PEI composite membranes were synthesized from tetraethoxysilane (TEOS) and poly (1-trimethylsilyl-1-propyne) (PTMSP) by sol-gel process. The PTMSP-silica nanocomposite membranes were characterized by $^1H-NMR$, FT-IR, TGA, XPS, SEM, GPC and gas permeation measurements were accomplished with $H_2,\;O_2,\;N_2,\;CO_2,\;CH_4$. The gases permeability increased with increasing TEOS content. Both the permeability and selectivity of $H_2,\;CH_4$ increased to 15 wt% TEOS. While the permeability of $O_2,\;CO_2$ increased without decrease of selectivity.

• Membrane and Water Treatment
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• v.8 no.3
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• pp.225-244
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• 2017

A novel thin-film nanocomposite (TFN) reverse osmosis (RO)/non-woven fabric (NWF) membrane was prepared by adding zinc oxide (ZnO) nanospheres ($30{\pm}10nm$) during the interfacial polymerization process of m-phenylenediamine (MPD) and trimesoyl chloride (TMC) on self-made polysulfone (PSF) membrane/polyester (PET) non-woven fabric support. The improved performance of TFN RO membrane was verified in terms of water contact angle (WCA), water flux, salt rejection, antifouling properties and chlorine resistance. The results showed that the WCA value of TFN RO surface had a continuous decrease with the increasing of ZnO content in MPD aqueous solution. The water flux of composite TFN RO membranes acquired a remarkable increase with a stable high solute rejection (94.5 %) in $1g{\cdot}L^{-1}$ NaCl aqueous solution under the optimized addition amount of ZnO (1 wt%). The continuous testing of membrane separation performance after the immersion in sodium hypochlorite solution indicated that the introduction of ZnO nanospheres also dramatically enhanced the antifouling properties and the chlorine resistance of composite RO membranes.

• Korean Membrane Journal
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• v.10 no.1
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• pp.20-25
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• 2008

Proton conducting composite membranes were prepared by solution blending of poly(vinylidene fluoride-co-chlorotrifluoroethylene)-graft-poly(sulfopropyl methacrylate) (P(VDF-CTFE)-g-PSPMA) graft copolymer and heteropolyacid (HPA). The P(VDF-CTFE)-g-PSPMA graft copolymer was synthesized by atom transfer radical polymerization (ATRP) using direct initiation of the secondary chlorines of P(VDF-CTFE). FT-IR spectroscopy revealed that HPA nanoparticles were incorporated into the graft copolymer via hydrogen bonding interactions. The water uptake of membranes continuously decreased with increasing HP A concentration up to 45wt%, after which it slightly increased. It is presumably due to the decrease in number of water absorption sites due to hydrogen bonding interaction between the HP A particles and the polymer matrix. The proton conductivity of membranes increased with increasing HPA concentration up to 45wt%, resulting from both the intrinsic conductivity of HP A particles and the enhanced acidity of the sulfonic acid of the graft copolymer.

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.4
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• pp.165-170
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• 2005

A series of inorganic-organic hybrid membranes were prepared with a systematic variation of titanium dioxide nanoparticle content. Their water uptake, methanol permeability and proton conductivity as a function of temperature were investigated. The results obtained show that the inorganic oxide network decreases the proton conductivity and water swelling. It is also found that increase in inorganic oxide content leads to decrease of methanol permeability. In terms of the morphology, membranes are homogeneous and exhibit good adhesion between inorganic domains and the polymer matrix. The properties of the composite membranes are compared with the standard nafion membrane.

• Membrane and Water Treatment
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• v.8 no.5
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• pp.463-481
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• 2017

Bacteria have been considered as a major foulant that initiates the formation of biofilm on the polymeric membrane surface. Some polymeric membranes are naturally antibacterial and have low fouling properties, however, numerous efforts have been devoted to improve their antibacterial performance. These modifications are mostly carried out through blending the membrane with an antibacterial agent or introducing the antibacterial agent on the membrane surface by chemical grafting. Currently, a significant number of researches have reported nanocomposite membrane as a new approach to fabricate an excellent antibacterial membrane. The antibacterial nanoparticles are dispersed homogenously in membrane structure by blending method or coating onto the membrane surface. Aim of the modifications is to prevent the initial attachment of bacteria to membrane surface and kill bacteria when attached on the membrane surface. In this paper, several studies on antibacterial modified membranes, particularly for water treatment, will be reviewed comprehensively. Special attention will be given on polymeric membrane modifications by introducing antibacterial agents through different methods, such as blending, grafting, and coating.

• Proceedings of the Membrane Society of Korea Conference
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• 2008.05a
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• pp.164-164
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• 2008

• Proceedings of the Membrane Society of Korea Conference
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• 2008.05a
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• pp.151-153
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• 2008

• Membrane Journal
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• v.34 no.3
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• pp.182-191
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• 2024

This review addresses the pressing need for effective wastewater treatment methodologies by exploring advanced thin-film nanocomposite (TFN) nanofiltration membranes aimed at efficient dye removal from industrial effluents. Utilizing insights from recent research, the review focuses on the fabrication of TFN membranes incorporating innovative materials such as nanocarbons, silica nanospheres, metal-organic frameworks (MOFs), and MoS₂. The primary goals are to enhance dye removal efficiency, improve antifouling properties, and maintain high selectivity for dye/salt separation. By leveraging the distinct advantages of these nanomaterials-including large surface areas, mechanical robustness, and specific pollutant interaction capabilities-this review aims to overcome the limitations of current nanofiltration technologies and provide sustainable solutions for water treatment challenges.

• Membrane Journal
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• v.33 no.4
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• pp.149-157
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• 2023

Covalent organic frameworks (COFs) have shown promise in various applications, including molecular separation, dye separation, gas separation, filtration, and desalination. Integrating COFs into membranes enhances permeability, selectivity, and stability, improving separation processes. Combining COFs with single-walled carbon nanotubes (SWCNT) creates nanocomposite membranes with high permeability and stability, ideal for dye separation. Incorporating COFs into polyamide (PA) membranes improves permeability and selectivity through a synthetic interfacial strategy. Three-dimensional COF fillers in mixed-matrix membranes (MMMs) enhance CO₂/CH₄ separation, making them suitable for biogas upgrading. All-nanoporous composite (ANC) membranes, which combine COFs and metal-organic framework (MOF) membranes, overcome permeance-selectivity trade-offs, significantly improving gas permeance. Computational simulations using hypothetical COFs (hypoCOFs) demonstrate superior CO₂ selectivity and working capacity relevant for CO₂ separation and H₂ purification. COFs integrated into thin-film composite (TFC) and polysulfonamide (PSA) membranes enhance rejection performance for organic contaminants, salt contaminants, and heavy metal ions, improving separation capabilities. TpPa-SO₃H/PAN covalent organic framework membranes (COFMs) exhibited superior desalination performance compared to traditional polyamide membranes by utilizing charged groups to enable efficient desalination through electrostatic repulsion, suggesting their potential for ionic and molecular separations. These findings highlight COFs' potential in membrane technology for enhanced separation processes by improving permeability, selectivity, and stability. In this review, COF applied for the separation process is discussed.