Preparation and Application of Novel Polymer Membranes

A special issue of Membranes (ISSN 2077-0375). This special issue belongs to the section "Membrane Applications".

Deadline for manuscript submissions: closed (30 November 2023) | Viewed by 12737

Special Issue Editor

Institute of Macromolecular Compounds, Russian Academy of Science, Bolshoy pr. V.O., 31, 199004 Saint-Petersburg, Russia
Interests: polymer membranes; mixed matrix membranes; composite and multilayer membranes; membrane preparation; phase inversion process; structure and morphology; ultrathin layers; polyelectrolyte complexes; transport properties: filtration, pervaporation

Special Issue Information

Dear Colleagues,

The wide variety of requirements for the processes of membrane separation, as well as methods and materials for obtaining membranes, has determined their diversity. The membrane material itself must match the membrane module, and the design of the module depends on both the process and the properties of the membrane. Until 1960, membranes were of little economic importance because they were of low productivity, often insufficiently selective, non-reproducible, and expensive. Many well-known separation processes became possible only after the invention of Loeb and Sourirajan asymmetric membranes, where the porosity of the membrane varies with its thickness (integral asymmetric membranes). The idea of an integral asymmetric membrane has overcome the flux problem and had been able to be applied to many polymers. The concept of composite membranes and methods for their preparation has changed. There are various types of composite membranes. Most often, these are membranes obtained by forming ultrathin films on porous membranes (supports). At the beginning of this century, there was another qualitative leap associated with the emergence of various methods for the formation of complex-morphology membranes. The development of membranes takes place not only in the chemical laboratory, but also (thanks to the improvement in computing power) with the help of molecular modeling.

Today, unprecedented opportunities are opening again in the study of membrane processes. This is due to a new stage in the study of polymeric membranes. Significant growth in the development of methods of analytical physics and chemistry and the emergence of new methods that allow a deep analysis of the internal structure of a polymer film of complex architecture led researchers to the stage of understanding the processes occurring not only with the use of a polymer membrane, but also inside it. It became possible to study the structure of (ultra)thin separating layers of polymer membranes, as well as its change as a result of separation processes. Examples of the successful use of structural modeling methods of surfaces, transport channels, and features of the internal structure of membranes are known. Information obtained at a new level on the effects of membranes’ structural features on their functional properties has led to the development of new methods and techniques for the target formation of polymer and polymer–inorganic composite membranes with the necessary properties.

In this Special Issue, we aim to publish new experimental data concerning the design, preparation and study of polymeric and polymer–inorganic membranes. We are also interested in receiving review articles providing an analysis of current methods for the formation of membranes as well as the study of their structural and morphological features and properties.

We look forward to receiving your contributions.

Dr. Svetlana V. Kononova
Guest Editor

Manuscript Submission Information

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Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • polymer
  • membrane
  • structure
  • composite
  • mixed-matrix membranes
  • coating layer
  • casting methods
  • transport properties
  • separation
  • filtration
  • pervaporation

Published Papers (10 papers)

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Research

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26 pages, 10017 KiB  
Article
Effect of Hydroxyl-Containing Fragments on the Structure and Properties of Membrane-Forming Polyamide-Imides
by Svetlana V. Kononova, Galina K. Lebedeva, Galina N. Gubanova, Elena V. Kruchinina, Elena N. Vlasova, Nadezhda V. Afanas’eva, Elena N. Popova, Anatoly Ya. Volkov, Elena N. Bykova and Natalya V. Zakharova
Membranes 2023, 13(8), 716; https://doi.org/10.3390/membranes13080716 - 01 Aug 2023
Viewed by 788
Abstract
The structural features and thermophysical and transport properties of dense nonporous membranes of the casting type from (co)polyamide-imides synthesized by the polycondensation of the diacid chloride of 2-(4-carboxyphenyl)-1,3-dioxoisoindoline-5-carboxylic acid and diamines 5,5′-methylene-bis (2-aminophenol) (DADHyDPhM) and 4,4′-methylenebis(benzeneamine) (DADPhM), taken in molar ratios of 7:3, [...] Read more.
The structural features and thermophysical and transport properties of dense nonporous membranes of the casting type from (co)polyamide-imides synthesized by the polycondensation of the diacid chloride of 2-(4-carboxyphenyl)-1,3-dioxoisoindoline-5-carboxylic acid and diamines 5,5′-methylene-bis (2-aminophenol) (DADHyDPhM) and 4,4′-methylenebis(benzeneamine) (DADPhM), taken in molar ratios of 7:3, 1:1, and 3:7, have been studied. The effect of hydroxyl-containing modifying fragments of dihydroxy diphenylmethane introduced in various amounts into the main polymer chain on the pervaporation properties of the formed films is discussed. It has been shown that the presence of the residual solvent N-methyl-2-pyrrolidone in the films not only has a plasticizing effect on the characteristics of film membranes but also promotes the preferential transmembrane transport of polar liquids, primarily methanol (permeation rate over 2 kg for a copolymer with a ratio of DADHyDPhM:DADPhM = 7:3). The removal of the residual solvent from the polymer film, both thermally (heating to 200 °C) and by displacement with another solvent as a result of sequential pervaporation, led to a significant decrease in the rate of transfer of polar liquids and a decrease in the selectivity of the membrane. However, the dehydrocyclization reaction resulted in more brittle films with low permeability to penetrants of different polarities. The results of our comprehensive study made it possible to assume the decisive influence of structural changes in membranes occurring in connection with the competitive formation of intra- and intermolecular hydrogen bonds. Full article
(This article belongs to the Special Issue Preparation and Application of Novel Polymer Membranes)
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13 pages, 2559 KiB  
Article
Simulation of the Membrane Process of CO2 Capture from Flue Gas via Commercial Membranes While Accounting for the Presence of Water Vapor
by Daria Miroshnichenko, Maxim Shalygin and Stepan Bazhenov
Membranes 2023, 13(8), 692; https://doi.org/10.3390/membranes13080692 - 25 Jul 2023
Viewed by 829
Abstract
Carbon capture and storage is one of the potential options for reducing CO2 emissions from coal-fired power plants while preserving their operation. Mathematical modeling was carried out for a one-stage membrane process of carbon dioxide capture from the flue gases of coal-fired [...] Read more.
Carbon capture and storage is one of the potential options for reducing CO2 emissions from coal-fired power plants while preserving their operation. Mathematical modeling was carried out for a one-stage membrane process of carbon dioxide capture from the flue gases of coal-fired power plants using commercial gas separation membranes. Our calculations show that highly CO2-permeable membranes provide similar characteristics with respect to the separation process (e.g., a specific area of membrane and a specific level of electrical energy consumption) despite the significant variation in CO2/N2 and H2O/CO2 selectivity. Regarding the development of processes for the recovery of CO2 from flue gas using membrane technology, ensuring high CO2 permeance of a membrane is more important than ensuring high CO2/N2 selectivity. The presence of water vapor in flue gas provides a higher driving force of CO2 transfer through the membrane due to the dilution of CO2 in the permeate. A cross-flow membrane module operation provides better recovery of CO2 in the presence of water vapor than a counter-current operation. Full article
(This article belongs to the Special Issue Preparation and Application of Novel Polymer Membranes)
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17 pages, 4976 KiB  
Article
Development of Hydrogen–Oxygen Fuel Cells Based on Anion-Exchange Electrolytes and Catalysts with Reduced Platinum Content
by Oleg Korchagin, Vera Bogdanovskaya, Inna Vernigor, Marina Radina, Irina Stenina and Andrey Yaroslavtsev
Membranes 2023, 13(7), 669; https://doi.org/10.3390/membranes13070669 - 14 Jul 2023
Viewed by 917
Abstract
Studies have been carried out to optimize the composition, formation technique and test conditions of membrane electrode assemblies (MEA) of hydrogen–oxygen anion-exchange membranes fuel cells (AEMFC), based on Fumatech anion-exchange membranes. A non-platinum catalytic system based on nitrogen-doped CNT (CNTN) was [...] Read more.
Studies have been carried out to optimize the composition, formation technique and test conditions of membrane electrode assemblies (MEA) of hydrogen–oxygen anion-exchange membranes fuel cells (AEMFC), based on Fumatech anion-exchange membranes. A non-platinum catalytic system based on nitrogen-doped CNT (CNTN) was used in the cathode. PtMo/CNTN catalysts with a reduced content of platinum (10–12 wt.% Pt) were compared with 10 and 60 wt.% Pt/CNTN at the anode. According to the results of studies under model conditions, it was found that the PtMo/CNTN catalyst is significantly superior to the 10 and 60 wt.% Pt/CNTN catalyst in terms of activity in the hydrogen oxidation reaction based on the mass of platinum. The addition of the Fumion ionomer results in minor changes in the electrochemically active surface area and activity in the hydrogen oxidation reaction for each of the catalysts. In this case, the introduction of ionomer–Fumion leads to a partial blocking of the outer surface and the micropore surface, which is most pronounced in the case of the 60Pt/CNTN catalyst. This effect can cause a decrease in the characteristics of MEA AEMFC upon passing from 10PtMo/CNTN to 60Pt/CNTN in the anode active layer. The maximum power density of the optimized MEA based on 10PtMo/CNTN was 62 mW cm−2, which exceeds the literature data obtained under similar test conditions for MEA based on platinum cathode and anode catalysts and Fumatech membranes (41 mW cm−2). A new result of this work is the study of the effect of the ionomer (Fumion) on the characteristics of catalysts. It is shown that the synthesized 10PtMo/CNTN catalyst retains high activity in the presence of an ionomer under model conditions and in the MEA based on it. Full article
(This article belongs to the Special Issue Preparation and Application of Novel Polymer Membranes)
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27 pages, 3980 KiB  
Article
Fabrication of PES Modified by TiO2/Na2Ti3O7 Nanocomposite Mixed-Matrix Woven Membrane for Enhanced Performance of Forward Osmosis: Influence of Membrane Orientation and Feed Solutions
by Ghadah M. Al-Senani, Mervat Nasr, Mohamed Zayed, Sahar S. Ali, Hind Alshaikh, Hanafy M. Abd El-Salam and Mohamed Shaban
Membranes 2023, 13(7), 654; https://doi.org/10.3390/membranes13070654 - 08 Jul 2023
Cited by 3 | Viewed by 1365
Abstract
Water treatment is regarded as one of the essential elements of sustainability. To lower the cost of treatment, the wastewater volume is reduced via the osmotic process. Here, mixed-matrix woven forward osmosis (MMWFO) PES membranes modified by a TiO2/Na2Ti [...] Read more.
Water treatment is regarded as one of the essential elements of sustainability. To lower the cost of treatment, the wastewater volume is reduced via the osmotic process. Here, mixed-matrix woven forward osmosis (MMWFO) PES membranes modified by a TiO2/Na2Ti3O7 (TNT) nanocomposite were fabricated for treating water from different sources. Various techniques were used to characterize the TNT nanocomposite. The crystal structure of TNT is a mix of monoclinic Na2Ti3O7 and anorthic TiO2 with a preferred orientation of (211). The SEM image shows that the surface morphology of the TNT nanocomposite is a forked nano-fur with varying sizes regularly distributed throughout the sample. The impact of TNT wt.% on membrane surface morphologies, functional groups, hydrophilicity, and performance was investigated. Additionally, using distilled water (DW) as the feed solution (FS), the effects of various NaCl concentrations, draw solutions, and membrane orientations on the performance of the mixed-matrix membranes were tested. Different water samples obtained from various sources were treated as the FS using the optimized PES/TNT (0.01 wt.%) MMWFO membrane. Using textile effluent as the FS, the impact of various NaCl DS concentrations on the permeated water volume was investigated. The results show that the MMWFO membrane generated with the TNT nanocomposite at a 0.01 wt.% ratio performed better in FO mode. After 30 min of use with 1 M NaCl and various sources of water as the FS, the optimized MMWFO membrane provided a steady water flow and exhibited antifouling behavior. DW performed better than other water types whenever it was used owing to its greater flow (136 LMH) and volume reduction (52%). Tap water (TW), textile industrial wastewater (TIWW), gray water (GW), and municipal wastewater (MW) showed volume reductions of 41%, 34%, 33%, and 31.9%, respectively. Additionally, when utilizing NaCl as the DS and TIWW as the FS, 1 M NaCl resulted in more permeated water than 0.25 M and 0.5 M, yet a higher volume reduction of 41% was obtained. Full article
(This article belongs to the Special Issue Preparation and Application of Novel Polymer Membranes)
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19 pages, 7118 KiB  
Article
Flexible Electrode Based on PES/GO Mixed Matrix Woven Membrane for Efficient Photoelectrochemical Water Splitting Application
by Ghadah M. Al-Senani, Mohamed Zayed, Mervat Nasr, Sahar S. Ali, Mohamed Shaban and Fatma Mohamed
Membranes 2023, 13(7), 653; https://doi.org/10.3390/membranes13070653 - 08 Jul 2023
Cited by 3 | Viewed by 1244
Abstract
We introduced, for the first time, a membrane composed of nanostructured self-polyether sulphone (PES) filled with graphene oxide (GO) applied to photoelectrochemical (PEC) water splitting. This membrane was fabricated through the phase inversion method. A variety of characteristics analysis of GO and its [...] Read more.
We introduced, for the first time, a membrane composed of nanostructured self-polyether sulphone (PES) filled with graphene oxide (GO) applied to photoelectrochemical (PEC) water splitting. This membrane was fabricated through the phase inversion method. A variety of characteristics analysis of GO and its composite with PES including FTIR, XRD, SEM, and optical properties was studied. Its morphology was completely modified from macro voids for bare PES into uniform layers with a random distribution of GO structure which facilitated the movement of electrons between these layers for hydrogen production. The composite membrane photocathode brought a distinct photocurrent generation (5.7 mA/cm2 at 1.6 V vs. RHE). The optimized GO ratio in the membrane was investigated to be PG2 (0.008 wt.% GO). The conversion efficiencies of PEC were assessed for this membrane. Its incident photon-to-current efficiency (IPCE) was calculated to be 14.4% at λ = 390 nm beside the applied bias photon-to-current conversion efficiency (ABPE) that was estimated to be 7.1% at −0.4 V vs. RHE. The stability of the PG2 membrane after six cycles was attributed to high thermal and mechanical stability and excellent ionic conductivity. The number of hydrogen moles was calculated quantitively to be 0.7 mmol h−1 cm−2. Finally, we designed an effective cost membrane with high performance for hydrogen generation. Full article
(This article belongs to the Special Issue Preparation and Application of Novel Polymer Membranes)
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18 pages, 6670 KiB  
Article
Flame-Resistant Poly(vinyl alcohol) Composites with Improved Ionic Conductivity
by Diana Serbezeanu, Corneliu Hamciuc, Tăchiță Vlad-Bubulac, Alina-Mirela Ipate, Gabriela Lisa, Ina Turcan, Marius Andrei Olariu, Ion Anghel and Dana Maria Preda
Membranes 2023, 13(7), 636; https://doi.org/10.3390/membranes13070636 - 30 Jun 2023
Cited by 1 | Viewed by 830
Abstract
Flame-resistant polymer composites were prepared based on polyvinyl alcohol (PVA) as a polymer matrix and a polyphosphonate as flame retardant. Oxalic acid was used as crosslinking agent. LiClO4, BaTiO3, and graphene oxide were also incorporated into PVA matrix to [...] Read more.
Flame-resistant polymer composites were prepared based on polyvinyl alcohol (PVA) as a polymer matrix and a polyphosphonate as flame retardant. Oxalic acid was used as crosslinking agent. LiClO4, BaTiO3, and graphene oxide were also incorporated into PVA matrix to increase the ionic conductivity. The obtained film composites were investigated by infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry and microscale combustion tests. Incorporating fire retardant (PFRV), BaTiO3, and graphene oxide (GO) into a material results in increased resistance to fire when compared to the control sample. A thermogravimetric analysis revealed that, as a general trend, the presence of PFRV and BaTiO3 nanoparticles enhances the residue quantity at a temperature of 700 °C from 7.9 wt% to 23.6 wt%. Their dielectric properties were evaluated with Broad Band Dielectric Spectroscopy. The electrical conductivity of the samples was determined and discussed in relation to the LiClO4 content. The electrical properties, including permittivity and conductivity, are being enhanced by the use of LiClO4. Additionally, a relaxation peak has been observed in the dielectric losses at frequencies exceeding 103 Hz. The electrical properties, including permittivity and conductivity, are being enhanced by the use of LiClO4. Additionally, a relaxation peak has been observed in the dielectric losses at frequencies exceeding 103 Hz. Out of the various composites tested, the composite containing 35 wt% of LiClO4 exhibits the highest alternating current (AC) conductivity, with a measured value of 2.46 × 10−3 S/m. Taking into consideration all the aspects discussed, these improved composites are intended for utilization in the manufacturing of Li-Ion batteries. Full article
(This article belongs to the Special Issue Preparation and Application of Novel Polymer Membranes)
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23 pages, 4505 KiB  
Article
Efficiency of Fabricated Adsorptive Polysulfone Mixed Matrix Membrane for Acetic Acid Separation
by Kavita Pusphanathan, Hafiza Shukor, Noor Fazliani Shoparwe, Muaz Mohd Zaini Makhtar, Nor’ Izzah Zainuddin, Nora Jullok, Masoom Raza Siddiqui, Mahboob Alam and Mohd Rafatullah
Membranes 2023, 13(6), 565; https://doi.org/10.3390/membranes13060565 - 30 May 2023
Cited by 1 | Viewed by 1088
Abstract
The ultrafiltration mixed matrix membrane (UF MMMs) process represents an applicable approach for the removal of diluted acetic acid at low concentrations, owing to the low pressures applied. The addition of efficient additives represents an approach to further improve membrane porosity and, subsequently, [...] Read more.
The ultrafiltration mixed matrix membrane (UF MMMs) process represents an applicable approach for the removal of diluted acetic acid at low concentrations, owing to the low pressures applied. The addition of efficient additives represents an approach to further improve membrane porosity and, subsequently, enhance acetic acid removal. This work demonstrates the incorporation of titanium dioxide (TiO2) and polyethylene glycol (PEG) as additives into polysulfone (PSf) polymer via the non-solvent-induced phase-inversion (NIPS) method to improve the performance of PSf MMMs performance. Eight PSf MMMs samples designated as M0 to M7, each with independent formulations, were prepared and investigated for their respective density, porosity, and degree of AA retention. Morphology analysis through scanning electron microscopy elucidated sample M7 (PSf/TiO2/PEG 6000) to have the highest density and porosity among all samples with concomitant highest AA retention at approximately 92.2%. The application of the concentration polarization method further supported this finding by the higher concentration of AA solute present on the surface of the membrane compared to that of AA feed for sample M7. Overall, this study successfully demonstrates the significance of TiO2 and PEG as high MW additives in improving PSf MMM performance. Full article
(This article belongs to the Special Issue Preparation and Application of Novel Polymer Membranes)
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Review

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30 pages, 3991 KiB  
Review
Advancements in Gas Separation for Energy Applications: Exploring the Potential of Polymer Membranes with Intrinsic Microporosity (PIM)
by Carmela Astorino, Eugenio De Nardo, Stefania Lettieri, Giuseppe Ferraro, Candido Fabrizio Pirri and Sergio Bocchini
Membranes 2023, 13(12), 903; https://doi.org/10.3390/membranes13120903 - 06 Dec 2023
Viewed by 1670
Abstract
Membrane-based Polymers of Intrinsic Microporosity (PIMs) are promising candidates for energy-efficient industrial gas separations, especially for the separation of carbon dioxide over methane (CO2/CH4) and carbon dioxide over nitrogen (CO2/N2) for natural gas/biogas upgrading and [...] Read more.
Membrane-based Polymers of Intrinsic Microporosity (PIMs) are promising candidates for energy-efficient industrial gas separations, especially for the separation of carbon dioxide over methane (CO2/CH4) and carbon dioxide over nitrogen (CO2/N2) for natural gas/biogas upgrading and carbon capture from flue gases, respectively. Compared to other separation techniques, membrane separations offer potential energy and cost savings. Ultra-permeable PIM-based polymers are currently leading the trade-off between permeability and selectivity for gas separations, particularly in CO2/CH4 and CO2/N2. These membranes show a significant improvement in performance and fall within a linear correlation on benchmark Robeson plots, which are parallel to, but significantly above, the CO2/CH4 and CO2/N2 Robeson upper bounds. This improvement is expected to enhance the credibility of polymer membranes for CO2 separations and stimulate further research in polymer science and applied engineering to develop membrane systems for these CO2 separations, which are critical to energy and environmental sustainability. This review aims to highlight the state-of-the-art strategies employed to enhance gas separation performances in PIM-based membranes while also mitigating aging effects. These strategies include chemical post-modification, crosslinking, UV and thermal treatment of PIM, as well as the incorporation of nanofillers in the polymeric matrix. Full article
(This article belongs to the Special Issue Preparation and Application of Novel Polymer Membranes)
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16 pages, 3210 KiB  
Review
Strategies to Mitigate Biofouling of Nanocomposite Polymer-Based Membranes in Contact with Blood
by Dominika Wójtowicz and Ewa Stodolak-Zych
Membranes 2023, 13(9), 762; https://doi.org/10.3390/membranes13090762 - 28 Aug 2023
Viewed by 831
Abstract
An extracorporeal blood purification method called continuous renal replacement therapy uses a porous hollow-fiber polymeric membrane that is exposed to prolonged contact with blood. In that condition, like with any other submerged filtration membrane, the hemofilter loses its properties over time and use [...] Read more.
An extracorporeal blood purification method called continuous renal replacement therapy uses a porous hollow-fiber polymeric membrane that is exposed to prolonged contact with blood. In that condition, like with any other submerged filtration membrane, the hemofilter loses its properties over time and use resulting in a rapid decline in flux. The most significant reason for this loss is the formation of a biofilm. Protein, blood cells and bacterial cells attach to the membrane surface in complex and fluctuating processes. Anticoagulation allows for longer patency of vascular access and a longer lifespan of the membrane. Other preventive measures include the modification of the membrane itself. In this article, we focused on the role of nanoadditives in the mitigation of biofouling. Nanoparticles such as graphene, carbon nanotubes, and silica effectively change surface properties towards more hydrophilic, affect pore size and distribution, decrease protein adsorption and damage bacteria cells. As a result, membranes modified with nanoparticles show better flow parameters, longer lifespan and increased hemocompatibility. Full article
(This article belongs to the Special Issue Preparation and Application of Novel Polymer Membranes)
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18 pages, 3338 KiB  
Review
Recent Advances in Membranes Used for Nanofiltration to Remove Heavy Metals from Wastewater: A Review
by Cristina Ileana Covaliu-Mierlă, Oana Păunescu and Horia Iovu
Membranes 2023, 13(7), 643; https://doi.org/10.3390/membranes13070643 - 04 Jul 2023
Cited by 3 | Viewed by 2603
Abstract
The presence of heavy metal ions in polluted wastewater represents a serious threat to human health, making proper disposal extremely important. The utilization of nanofiltration (NF) membranes has emerged as one of the most effective methods of heavy metal ion removal from wastewater [...] Read more.
The presence of heavy metal ions in polluted wastewater represents a serious threat to human health, making proper disposal extremely important. The utilization of nanofiltration (NF) membranes has emerged as one of the most effective methods of heavy metal ion removal from wastewater due to their efficient operation, adaptable design, and affordability. NF membranes created from advanced materials are becoming increasingly popular due to their ability to depollute wastewater in a variety of circumstances. Tailoring the NF membrane’s properties to efficiently remove heavy metal ions from wastewater, interfacial polymerization, and grafting techniques, along with the addition of nano-fillers, have proven to be the most effective modification methods. This paper presents a review of the modification processes and NF membrane performances for the removal of heavy metals from wastewater, as well as the application of these membranes for heavy metal ion wastewater treatment. Very high treatment efficiencies, such as 99.90%, have been achieved using membranes composed of polyvinyl amine (PVAM) and glutaraldehyde (GA) for Cr3+ removal from wastewater. However, nanofiltration membranes have certain drawbacks, such as fouling of the NF membrane. Repeated cleaning of the membrane influences its lifetime. Full article
(This article belongs to the Special Issue Preparation and Application of Novel Polymer Membranes)
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