Hydrophilic Membrane Research Articles

Combination of fluorescent and spin labels: a powerful method for the optimization of hydrophilic membranes for the separation of oil-in-water emulsions

A new method for assessing the quality of fibre coating based on a combination of fluorescence microscopy and electron paramagnetic resonance is presented in this work. An influence of the carboxymethylcellulose/polyvinylamine gel preparation method on the mobility of the spin label was established. The mobility of the spin label changes from 3.5 ns in the case of a polyvinylamine solution to 12.8 ns in the case of a cross-linked gel on the surface of the glass fibre. A qualitative relationship was found between the mobility of the spin label in the gel applied to the glass fibre and the rate of spreading of crude oil over its surface. This method can be used to make membranes for the separation of water-in-oil emulsions.

Unveiling the impact of monomer reactivity on the morphology and functionality of thin-film composite membranes

This study delves into the impact of monomer selection and reaction pH on the morphology and performance of thin-film composite (TFC) membranes. The research provides an understanding of how polyamide (PA), polyester amide (PEA), and polyester (PE) membranes can be tailored for specific applications, employing piperazine (PIP) and glucose as monomers in aqueous solution alongside trimesoyl chloride (TMC) as a monomer in an organic solution. PEA-based membranes containing glucose demonstrated several notable improvements, including a reduced contact angle of 60 degrees, a smoother surface, and a more negative zeta potential. These enhancements underscore their increased hydrophilicity, decreased susceptibility to fouling, and heightened surface charge. Controlling pH during fabrication significantly changed the membrane surface charge, hydrophilicity, water flux, and rejection rate. At pH 11, the PA membrane excelled in rejection performance (99.5% Na2SO4, 32% NaCl, and 97.8% methyl orange) with a trade-off in lower water flux (56 LMH). Conversely, the PE membrane achieved the highest water flux (173 LMH) but lower rejection (58% Na2SO4, 10% NaCl, and 97% methyl orange). The PEA membrane offered notable water flux (82.5 LMH) and high rejection for methyl orange (99.3%) and Na2SO4 (99.2%). Increasing the pH reduced permeation rates but enhanced rejection, especially for NaCl. The PE and PEA membranes exhibited remarkable antifouling properties, boasting a flux recovery ratio compared to the PA membrane. This study highlights the pivotal role of monomer selection and pH control in TFC membrane performance, offering prospects for innovative design and optimization in water treatment membrane technology.

Preparation and Characterization of Polyethersulfone/Activated Carbon Composite Membranes for Water Filtration.

Ultrafiltration membrane technology holds promise for wastewater treatment, but its widespread application is hindered by fouling and flux reduction issues. One effective strategy for enhancing ultrafiltration membranes involves incorporating activated carbon powder. In this study, composite polyethersulfone (PES) ultrafiltration membranes were fabricated to include activated carbon powder concentrations between 0 and 1.5 wt.%, with carbon size fixed at 200 mesh. The ultrafiltration membranes were evaluated in terms of membrane morphology, hydrophilicity, pure water flux, equilibrium water content, porosity, average pore size, protein separation, and E-coli bacteria removal. It was found that the addition of activated carbon to PES membranes resulted in improvements in some key properties. By incorporating activated carbon powder, the hydrophilicity of PES membranes was enhanced, lowering the contact angle from 60° to 47.3° for composite membranes (1.0 wt.% of activated carbon) compared to the pristine PES membrane. Water flux tests showed that the 1.0 wt.% composite membrane yielded the highest flux, with an improvement of nearly double the initial value at 2 bar, without compromising bovine serum albumin rejection or bacterial removal capabilities. This study also found that the inclusion of activated carbon had a minor impact on the membrane's porosity and equilibrium water content. Overall, these insights will be beneficial in determining the optimal concentration of activated carbon powder for PES ultrafiltration membranes.

In situ bridges of nano-titanium dioxide constructed in MXene self-cleaning loose nanofiltration membranes for dye wastewater treatment

It has been a longstanding problem to combat the oxidation process of MXene membranes. Here, we propose a strategy to construct nano bridge defect repair loose nanofiltration membrane with the help of MXene oxidation. The oxidation kinetics of Ti3C2Tx was investigated in both model and experimental aspects. The acid solution leads to aggregation and smaller d-spacing. However, the oxidation of MXene was accelerated in alkaline solution via reaction with hydroxyl anions resulting in a hydrophilic MXene membrane surface. The water permeability of the pH = 12-Ti3C2Tx membrane increased to a maximum value of 26.5 L·m−2·h−1·bar−1 together with a high rejection (98 %) of Janus green B (JGB). Titanium dioxide, which was in situ formed by oxidation of MXene, gives the membrane self-cleaning properties under UV light. The water recovery ratio was as high as 96.6 %. To further study the mechanism of in situ oxidation of MXene to form nano-titanium dioxide, the oxidation stages were analyzed which revealed that the in-situ oxidation process involved three different oxidations stages. This research offers a new perspective on MXene membrane design, paving the way for a new method of in situ nano bridge defect repair loose MXene nanofiltration membrane.

Enhanced separation performance of composite nanofiltration membranes via electrostatic air spray PSS/PEI interlayer

Thin-film composite (TFC) membranes with an interlayer were prepared extensively for desalination, but the hydrophilicity and permeability were not well improved. In this work, a smooth and hydrophilic interlayer was constructed by electrostatic air spray deposition (EASD) of poly (sodium 4-styrenesulfonate) (PSS) and polyethyleneimine (PEI) on the polyethersulfone substrate and an ultra-thin separation layer was prepared using interfacial polymerization of piperazine (PIP) and trimesoyl chloride (TMC) to acquire high-performance composite nanofiltration (NF) membranes. The polymer solution was atomized into tiny particles under a high-pressure electrostatic air spray effect, facilitating the deposition of PSS/PEI with good homogeneity and enabling a denser and smoother interlayer surface. The introduction of PSS/PEI enhanced the hydrophilicity of TFC membranes and increased the repulsion of divalent cations to improve the salt rejection. The impacts of PEI concentration and EASD time on the separation performance of NF membrane were explored. The optimized TFC-3 NF membrane had a permeate flux of 74.5 ± 1.6 L·m−2·h−1 under 0.5 MPa, which was 2.5 times higher than the water flux of conventional TFC-0 membrane, while retaining up to 99.2 ± 0.5 % of Na2SO4. This work provides a prospective strategy to develop high-performance TFC membranes with great extensive progress for seawater purification.

Synergistic effect of POSS and chitosan on highly enhancing the separation selectivity and antifouling capacity of polyamide membranes

The trade-off limit between permeability and selectivity, along with membrane fouling, has consistently posed significant challenges impeding the practical implementation of water purification membranes. In this paper, a combination of polyhedral oligomeric silsesquioxanes (POSS) and chitosan is introduced into the polyamide layer through interfacial polymerization and crosslinking to optimize the physical, chemical structure of membrane simultaneously. The resulting P/CS-2-POSS-2 membrane exhibits a notable water flux of 221.3 L m−2 h−1 MPa−1 and a substantial Na2SO4 rejection of 97.1 %. The selectivity of water molecules over sulfates in the optimized hybrid membrane is approximately 4 times greater than that observed in the pristine polyamide membrane. This finding underscores the success of the developed method in mitigating the trade-off between permeability and selectivity. Furthermore, the hybrid membranes exhibit superior antifouling properties, as evidenced by an impressive flux recovery ratio of 95.8 % for bovine serum albumin. Additionally, the mass transport properties of the prepared membranes are explored via molecular dynamics (MD) simulations. The results highlight that chitosan primarily enhances the membrane's hydrophilicity, whereas POSS predominantly regulates the membrane's pore size. Both fillers synergistically enhance the comprehensive performance of the membrane by effectively utilizing steric hindrance and the Donnan effect.

Macromolecule crosslinked composite PVA membranes for pervaporation desalination

Pervaporation (PV) has shown great potential in desalination. Polyvinyl alcohol (PVA) is a widely used material for PV membranes. In the present work, hydrophilic composite membranes for PV desalination were prepared by coating mix solutions of PVA and Poly(methyl vinyl ether-alt-maleic anhydride) (PMVE-MA) on porous polyvinylidene fluoride (PVDF) supports. PMVE-MA, which serves as a macromolecular crosslinker, is well-compatible with PVA. The methyl ether groups in PMVE-MA also endow the crosslinked membrane to maintain good hydrophilicity. To achieve better performance, influences of the PVA concentration, the mass ratio of PVA to PMVE-MA, the crosslinking temperature and time, and the PVDF support on the desalination performance of the composite PV membrane were studied. At optimal conditions, a PVA-(PMVE-MA)/PVDF membrane was prepared. The membrane had a water flux of up to 45 kg·m−2·h−1 for the feed of 3.5 wt% NaCl solution at 50 °C (92 kg·m−2·h−1 at 70 °C). The salt passage was at an extremely low level and the conductivity of the permeate was lower than 100 μs/cm. In addition, the membrane showed excellent antifouling performance. After 14 h desalination of a sodium alginate-containing feed, the flux can be fully recovered by flushing the membrane in situ. The PVA-(PMVE-MA)/PVDF composite membrane shows great potential in desalination applications.

Electrospun Polysulfone Hybrid Nanocomposite Fibers as Membrane for Separating Oil/Water Emulsion

Commercial polymer membranes are largely utilized to separate oil/water mixtures; however, membrane fouling, flux decline, and short lifetime often inhibit their high performance. In order to resolve these drawbacks of the commercial membranes, we introduce a surface modification strategy following the electrospinning method. Electrospun fibers of polysulfone (PSf)/iron oxide (FeO)/halloysite nanotubes (HNT) nanocomposite are applied to modify the polyether sulfone (PES) standard membrane support surface for developing highly efficient oil/water emulsion separating membranes. This facile and simple spinning process for shorter periods ensures nanocomposite coatings on the standard PES membranes and allows a better oil/water separation. We analyze the structural and morphological characteristics of the modified membrane surface using scanning electron microscopy, Fourier transformation infrared spectroscopy, and X-ray diffraction studies and hydrophilicity from contact angle studies. FeO nanoparticles of 2–5 nm and HNTs of < 50 nm size mixed in PSf produce fibers of 531 ± 162 nm average diameter at a relatively lower applied electrical voltage of 14.5 kV, compared to PSf. Underwater and under-oil contact angle values are used to prove the surface characteristics of the membranes and total organic content (TOC) values for the emulsion separation performance. From PES support to PSf and PSf/HNT-FeO, the TOC values respectively change from 67 to 75 and 79%. We find moderately hydrophilic membranes (PSf/HNT-FeO) resulting in a higher permeate flux (28,447 Lm−2·h−1) and quicker separation performance. We believe this study provides a notable solution to modify the surface of commercial membranes for better emulsion separation performance.

Preparation of BiOBr/PVDF photocatalytic membranes for long-term and efficient degradation of organic dyes using phase transition and in situ deposition methods

Purpose This study aims to investigate the morphology and physicochemical properties of BiOBr/Polyvinylidene fluoride (PVDF) composite membranes and the differences in the properties of BiOBr/PVDF composite membranes made by adding different precursor ratios during the casting process. Design/methodology/approach In this paper, sodium bromide and Bi(NO3)3 were used as precursors for the preparation of BiOBr photocatalysts, and PVDF membranes were modified by using the phase conversion method in conjunction with the in situ deposition method to produce BiOBr/PVDF hydrophilic composite membranes with both membrane separation and photocatalytic capabilities. Findings The characterization results confirmed that the composites were successfully and homogeneously co-mingled in the PVDF membranes. The related performance of the composite membrane was tested, and it was found that the composite membrane with the optimal precursor incorporation ratio had good photocatalytic efficiency and antipollution ability; the removal efficiencies of methyl orange, rhodamine B and methylene blue were 80.43%, 85.02% and 86.94%, respectively, in 2.5 h. The photocatalytic efficiency of composite membranes with different precursor ratios increased and then decreased with the increase of the precursor addition ratio. Originality/value The composite membrane is prepared by phase conversion method with in situ deposition method, and the BiOBr material has unique advantages for the degradation of organic dyes. The comprehensive experimental data can be known that the composite membrane prepared in this paper has high degradation efficiency and good durability for organic dyes.

Mathematical modeling and evaluation of permeation and membrane separation performance for Fischer–Tropsch products in a hydrophilic membrane reactor

Abstract A mathematical model was constructed to estimate the performance of an MFI-membrane reactor used for Fischer–Tropsch synthesis to produce a mixture of liquid hydrocarbons. In order to accurately evaluate the reactor’s performance a parametric study was performed. Under certain operational conditions, such as the total initial pressure in the reaction zone (1–4 MPa) and the hydrogen/carbon monoxide ratio (H2/CO: 1 to 2) on the performance of the studied reactor. The selectivity (productivity) of the hydrocarbon products (S i ), the quantity of hydrocarbons permiated (θ i ) and the separation factors of each space (α i ) were predicted. With increasing pressure, it is observed that θ CO and θ H 2 ${\theta }_{{H}_{2}}$ are decreasing from 0.62 to 0.45 and from 0.55 to 0.49 respectively. However, as the H2/CO ratio rises, this measurement shows a slight increase. Aside from, the separation factors of the majority of the current species are unaffected by the H2/CO ratio increasing, while the separation factors of carbon monoxide and hydrogen are increasing. Similarly the selectivity of water, methane, carbon dioxide and ethane increases with increasing H2/CO ratio. Based on these findings it is revealed that the membrane can enable permeability for all species present in the products mixture with varying separation factors, and that the ability to separate species other than water from the reaction side is essentially non-existent.

Hydrophilic Graphene Oxide Membrane Intercalated by Halloysite Nanotubes for Oil-in-Water Emulsion Separation

Hydrophilic Graphene Oxide Membrane Intercalated by Halloysite Nanotubes for Oil-in-Water Emulsion Separation

Development and characterization of porous membranes based on PPSU/PES using polyethylene glycol as porogen: Application for cobalt removal by polyelectrolyte‐enhanced ultrafiltration

AbstractBACKGROUNDIn this work, a polyphenylsulfone/polyethersulfone (PPSU/PES) composite membrane was successfully prepared using the phase‐inversion method in the presence of polyethylene glycol (PEG) as a hydrophilic additive. The effect of concentration of PEG (0, 2, 4 and 6 wt%) was investigated by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and contact angle analysis.RESULTSThe obtained results confirmed that the morphology and hydrophilicity of the porous membrane varied with the addition of PES as reinforcing agent and the PEG concentration as porogen. SEM results confirmed that the membranes obtained have a high permeability with a finger‐shaped structure and that the size and density of the pores increase with an increase in the incorporated PEG. The contact angle was decreased and the porosity of the PPPn blend membranes was increased from 16.06 for the neat PPSU membrane to 385.3 L h−1 m−2 bar−1 for the PPP6 membrane. A strong interaction between the components (PPSU, PES and PEG) was revealed by FTIR spectroscopy and TGA.CONCLUSIONThe filtration results showed that PPP2 is the better formulation of the dope suspension in the range of ultrafiltration membranes in terms of flux (179.3 L h−1 m−2 bar−1) and bovine serum albumin retention (94%). The application of polyelectrolyte‐enhanced ultrafiltration using polyethylenimine (PEI) for the removal of cobalt ions afforded high removal rates (92.5%). The optimal performances were obtained at pH ≥ 4, transmembrane pressure of 4 bar and 1200 ppm of PEI. © 2023 Society of Chemical Industry (SCI).

Preparation of polypropylene with photothermal conversion and hydrophilicity by one-step impregnation for efficient interfacial water evaporation

Solar-driven interfacial water evaporation is a technology that is currently attracting significant interest for tackling freshwater scarcity. However, the creation of porous membranes with photothermal conversion and hydrophilicity remains a challenging task. This study utilizes melt-blown polypropylene nonwoven (PP), a substrate with high porosity, low cost and high yield, to prepare evaporation membranes exhibiting photothermal conversion properties. The PP surface was treated with a one-step impregnation method to produce both shell and nanoparticles containing MnO2−x. The addition of MnO2−x grants the PP membranes both photothermal conversion and hydrophilicity simultaneously. Sunlight absorption efficiency of PP membranes covered with MnO2−x (M-PP) is 85.83%, and its hydrophilicity and porosity enable it to form an ultra-thin layer of water during evaporation, promoting rapid escape of vapors. Evaporation rate of M-PP membranes reach 1.02 kg m−2 h−1, much higher than that of PP and bulk water. In addition, M-PP membranes have excellent corrosion resistance, which is potentially valuable in treating wastewater and desalinating seawater.

Development, performance research and shape memory multifunctional exploration of epoxy/PEG shape memory nanofibers

To improve the spinnability of thermoplastic epoxy resin and develop epoxy resin-based shape memory nanofiber materials, polyethylene glycol (PEG) was utilized to regulate the properties of thermoplastic epoxy. The process involved the preparation of thermoplastic epoxy/PEG nanofibers using melt-dispersion and electrospinning techniques. The addition of PEG has enabled the electrospinning of the thermoplastic epoxy, with EPP-5 having the smallest average diameter (227 nm) and EPP-10 showing the most uniform morphology. FTIR analysis confirmed sufficient polymerization of epoxy resin. The water contact angle analysis revealed that an appropriate amount of PEG reduced the hydrophilicity of the nanofiber membranes, with the EPP-10 showing a 14.9 ° increase in water contact angle compared to the EPP-5. The mechanical analysis demonstrated that an appropriate amount of PEG improved the nanofibers’ yield stress, breaking strain, and maximum tensile stress. The EPP-10 exhibited a 3.27 MPa increase in yield stress, a 19.54 % increase in breaking strain, and a 1.17 MPa increase in maximum tensile stress compared to the EPP-5. Thermal analysis showed that epoxy/PEG nanofibers decomposed mainly between 400 ℃ and 500 ℃. Thermomechanical analysis revealed a reduction in the Tg of epoxy/PEG films with the addition of PEG, among which the Tg of EPP-25 was 55.1 ℃ lower than that of EPP-0. The epoxy/PEG nanofiber membrane exhibits excellent shape memory performance, among which the EPP-10 exhibits the best shape recovery effect. In addition, the EPP-10 yarn stretched to 160 % of original length recovered within 25 s, and EPP-10 yarn tied in a temporary shape recovered to original shape within 15 s. In conclusion, by modulating the properties of thermoplastic epoxy through PEG, the spinnability of thermoplastic epoxy was achieved, and shape memory epoxy/PEG nanofibers with potential applications in the field of smart textiles were developed.

Facile fabrication of ceramic-based highly permeable composite nanofiltration membranes by in-situ interfacial polymerization

The preparation of thin-film composite (TFC) membranes with both extraordinary permeance and excellent rejection performance are still a challenge due to the irreversible and rapid interfacial polymerization (IP). The high reactivity of amine monomers helps to form a defect-free membrane instantaneously during the IP process, but also ultimately leads to low water permeance. Here, a facile strategy was proposed to improve the performance of TFC membrane by conducting in-situ IP on the nanoporous ceramic membranes. First, it was confirmed that the hydrophilic ceramic membrane, which serves as an oil-water interface, can provide a uniform aqueous layer. The free-like interface is conductive to the formation of defect less polyamide layer even at ultra-low monomer concentrations and very short reaction times. Then, the performance of TFC membranes using ceramic membranes with different pore sizes as supports was systematically investigated. The result indicates that supports with smaller pore size and narrower distribution enable facilitate the formation of a thinner membrane. Moreover, the nanofiltration membrane exhibited ultra-high pure water permeances of 42.9 LMH/bar and a rejection of 93.4 % to Na2SO4, utilizing a ceramic membrane with a pore size of 10 nm as support under PIP of 0.025 wt% and reaction times of 10 s.

A convergent fabrication of graphene oxide/silk fibroin/hydroxyapatite nanocomposites delivery improved early osteoblast cell adhesion and bone regeneration

For controlled bone regeneration, two-dimensional materials are essential because they provide an isolated area for bone regeneration and protect the surrounding tissues. Excellent mechanical and hydrophilic qualities have made graphene oxide (GO) a common choice for bone regeneration. A biomimetic mineralization process combined with one-step vacuum filtering created mechanically strong and biocompatible two-dimensional (2D) membranes. Silk fibroin (SF) and hydroxyapatite (HA) increased the membranes' mechanical strength and hydrophilicity on the surface. Osteoblast adhesion, differentiation, and mineralization improved with little HA administered. A calvarial defect model was used to test the impact of the produced composite membranes on bone formation in vivo after they were implanted. Histological examination demonstrates that bone regeneration may be accelerated by GO/SF/HA composite membranes without needing endogenous cytokines. GO/SF/HA nanocomposite membranes with distinctive porous architectures, exceptional mechanical characteristics, and excellent bone regeneration capability are viable nanocomposites for bone regeneration.

Structure and performance of polyvinylchloride microfiltration membranes improved by green silicon oxide nanoparticles for oil-in-water emulsion separation

Oil-in-water (O/W) emulsion separation has received wide attention in the field of industrial water treatment. Mixed matrix polyvinylchloride (PVC) membranes containing 0.1–1.5 wt% silicon oxide (SiO2) as an inorganic additive obtained from two different sources were fabricated via the phase inversion method. The impact of embedding SiO2 in the PVC texture was studied by making a comparison between SiO2 nanoparticles prepared from common water reeds as a bio-source (namely bio SiO2) and commercial SiO2. The fabricated membranes were characterized via Fourier-transform infrared spectroscopy, field emission scanning electron microscope, and atomic force microscopy. Also, the water contact angle and water flux were measured. The results of the water contact angle revealed that modification of the PVC membrane by 0.5 wt% bio SiO2 reduced the contact angle from 82.3° for the neat PVC membrane to 29.7° showing that high enhancement in the membrane's hydrophilicity. The effect of oil feed concentrations (100–1000 mg/L) and temperature (25, 35, and 45 °C) on the treatment efficiency and permeate flux was investigated at trans-membrane pressures (1.5, 2.5, and 3.5 bar). The results showed that the permeation flux of the modified membranes was higher than that of the neat membrane due to enhancing the membrane's properties. Finally, the membranes were evaluated in a crossflow system with simulated O/W emulsion as a feed. The bio SiO2/PVC membranes have applicable potential in the oily wastewater treatment for their low price, good antifouling performance, and high removal efficiencies of NTU (over 98.15 %), COD (up to 99.19 %) for a membrane containing 0.5 wt% bio SiO2 used for 100 mg/L O/W emulsion.

A facile method to fabricate anti-fouling nanofiltration membrane with aminated lignin

Nanofiltration (NF) membrane separates materials with molecular weight of 200–2000 Da effectively. However, the membrane fouling is inevitable, which can deteriorate the membrane performance and service life. Meanwhile, the common additives improving the anti-fouling performance may bear high cost and involve complex synthesis process. In this work, biomass material lignin is chemically modified (LG-NH2) and utilized in the interfacial polymerization process to improve the hydrophilicity and ant-fouling property of NF membranes. Both the reversible and irreversible fouling are reduced. In addition, the LG-NH2 optimizes the membrane pore size and increases the permeability of NF membrane, while the rejection to Na2SO4 is marginally affected, although the rejection to MgCl2 drops. Finally, the NF membrane is applied for biogas slurry valorization and demonstrates great potential. This work thus not only provides a convenient and cheap method to fabricate anti-fouling NF membranes, but also a potential route for the utilization of biomass, i.e., lignin and biogas slurry.

Development of Novel PET-PAN Electrospun Nanocomposite Membrane Embedded with Layered Double Hydroxides Hybrid for Efficient Wastewater Treatment.

Layered double hydroxides (LDHs) with their unique structural chemistry create opportunities to be modified with polymers, making different nanocomposites. In the current research, a novel PET-PAN embedded with Mg-AI-LDH-PVA nanocomposite membrane was fabricated through electrospinning. SEM, EDX, FTIR, XRD, and AFM were carried out to investigate the structure and morphology of the nanocomposite membrane. The characterization of the optimized nanocomposite membrane showed a beadless, smooth structure with a nanofiber diameter of 695 nm. The water contact angle and tensile strength were 16° and 1.4 Mpa, respectively, showing an increase in the hydrophilicity and stability of the nanocomposite membrane by the addition of Mg-Al-LDH-PVA. To evaluate the adsorption performance of the nanocomposite membrane, operating parameters were achieved for Cr(VI) and methyl orange at pH 2.0 and pH 4.0, respectively, including contact time, adsorbate dose, and pollutant concentration. The adsorption data of the nanocomposite membrane showed the removal of 68% and 80% for Cr(VI) and methyl orange, respectively. The process of adsorption followed a Langmuir isotherm model that fit well and pseudo-2nd order kinetics with R2 values of 0.97 and 0.99, respectively. The recycling results showed the membrane's stability for up to five cycles. The developed membrane can be used for efficient removal of pollutants from wastewater.

Novel partially cross-linked nanoparticles graft co-polymer as pore former for polyethersulfone membranes for dyes removal

A newly developed water-soluble polymeric nano-additive termed “partially cross-linked nanoparticles graft copolymer (PCLNPG)" has been successfully synthesized and harnessed as a pore former for modifying a polyethersulfone ultrafiltration membrane for dyes removal. The PCLNPG content was varied in the PES polymeric matrix aiming to scrutinize its impact on membrane surface characteristics, morphological structure, and overall performance. Proposed interaction mechanism between methylene blue (MB), methyle orange (MO), and malachite green (MG) dyes with PES membrane was presented as well. Hydrophilicity and porosity of the novel membrane increased by 18 and 17 %, respectively, when manufactured with a 3 Wt. % PCLNPG, according to the findings. Besides this, the disclosed increased porosity, rather than the hydrophilic properties of the water-soluble PCLNPG, was the principal cause of the diminished contact angle. Meanwhile, raising the PCLNPG content in the prepared membrane made worthy shifts in its structure. A sponge-like region was materialized near the bottom surface as well. The membrane's pure water flux (PWF) synthesized with 3 Wt.% PCLNPG recorded 628 LMH, which is estimated 3.95 fold the pristine membrane. MG, MB, and MO dyes were rejected by 90.6, 96.3, and 97.87 %, respectively. These findings showed that the performance characteristics of the PES/PCLNPG membrane make it a potentially advantageous option to treat the textile wastewater.