Excellent Antifouling Properties Research Articles

Polyelectrolyte interlayer assisted interfacial polymerization fabrication of a dual-charged composite nanofiltration membrane on ceramic substrate with high performance

Interfacial polymerization has been applied to prepare polyamide membrane for wastewater treatment. It faces challenges in simultaneously rejection of divalent anions/cations. Moreover, weak interfacial bonding appears when the polyamide layer is formed on the ceramic substrate. Herein, a dual-charged composite nanofiltration (NF) membrane (CM-(CS/SA)1-PA) on ceramic ultrafiltration substrate, comprising a positive charged polyelectrolyte interlayer and a negatively charged polyamide separation layer, was obtained by layer-by-layer (LBL) self-assembly of chitosan/sodium alginate and subsequently interfacial polymerization. The interlayer with positive charge and excess amino group, can not only react to form covalent bonds with the polyamide layer, but also promote the divalent anions/cations rejection. The prepared PA layer is thin and dense with a thickness of ∼20 nm. The MWCO of the composite membrane is 527 Da with a pure water flux of 60.41 L m−2 h−1 at 0.4 MPa. The prepared composite membrane maintains good rejection for divalent anions/cations (MgSO4 88.11%, Na2SO4 89.11%, MgCl2 81.65%, CaCl2 80.45%) and multiple charged dyes (mthylene blue 99.83%, congo red 98.72%, active blue 19 97.7%, methyl orange 93.92%, rhodamine B 93.1%). During the 40 h constant filtration, the 126 h sustained immersion in ethanol and the 24 h immersion in solutions with pH from 6 to 10, the composite membrane shows excellent stability. Moreover, the unique dual-charged structure and the hydrophilic/smooth membrane surface promote the anti-fouling property in multiple charged dyes separation. In conclusion, the construction of polyelectrolyte interlayer provides a new approach for the preparation of a dual-charged composite NF membrane on ceramic substrate with excellent interfacial stability and anti-fouling property. It has potential applications in wastewater treatment, such as desalination and dyes removal.

Poly(vinyl alcohol)-based highly permeable TFC nanofiltration membranes for selective dye/salt separation

Loose nanofiltration (LNF) membranes possessing high water permeance and outstanding dye/salt selectivity are highly desirable for fractionating dyes and salts for textile wastewater. Herein, inexpensive and nontoxic poly(vinyl alcohol) (PVA) was utilized as an aqueous monomer via interfacial polymerization to fabricate novel highly permeable LNF membranes upon activation by sodium hydroxide. Systematic chemical and structural analyses indicated that the prepared polyester membrane formed was loose, hydrophilic, and negatively charged. The properties of the LNF membranes were optimized by adjusting the curing temperature (70 °C–100 °C). The optimized PVA-based membrane (PVA-M70°C) showed excellent water permeability (52.6 L m−2 h−1 bar−1), favorable dye rejection (> 90.0 %) and low salt rejection (NaCl and Na2SO4 rejection rates were lower than 5 % and 18 %, respectively). Furthermore, the PVA-M membrane demonstrated excellent antifouling properties and long-term stability. Considering the biodegradable nature and low cost of PVA, PVA-based polyester membranes show great promise for LNF membrane production on an industrial scale. This work advances the use of PVA as a green aqueous monomer in fabricating highly permeable LNF membranes for efficient dye/salt selectivity.

Novel organic–inorganic hybrid polymer based on fluorinated polyhedral oligomeric silsesquioxanes for stable superamphiphobic fabrics and aluminum corrosion protection

Methoxysilane substituted fluorinated silsesquioxane (F-POSS) was first synthesized by a simple ‘thiol-ene’ reaction of octamercaptopropyl silsesquioxane with perfluorohexyl ethylene and trimethoxyvinylsilane (VITMS) under an ultraviolet light condition. Then, by dip-coating F-POSS onto a cotton fabric surface, a durable and stable superamphiphobic fabric (F-POSS-Fabric) was successfully obtained through a sol-gel process. The multiscale structure and surface chemical composition of F-POSS-Fabric were characterized by field emission scanning electron microscopy and X-ray photo-electron spectroscopy. F-POSS-Fabric showed excellent mechanical, chemical stability, and self-cleaning and antifouling properties. F-POSS-Fabric can separate oil and water mixtures efficiently (separation efficiency higher than 99%, maximum flux up to 80,562 L/m2/h). F-POSS can also be used as a protective coating for metallic aluminum (Al) to resist corrosion by acid, alkali, and seawater. The corrosion protection efficiency of an F-POSS coating was about 84.6%, and the impedance of Al was raised from 7698 to 1.8∗105 Ω/cm2.

Mechanochemical stable superhydrophobic coating toward lasting corrosion protection

Superhydrophobic coatings are vulnerable to protection failures in long-term practical applications due to the decomposition of low surface energy materials and destruction of rough structures. In this work, a self-healing dual-layer polydimethylsiloxane/superhydrophobic coating was constructed on the Al alloy toward corrosion protection. The coating with a water contact angle of 151 ± 2.4° exhibits excellent low water adhesion, self-cleaning, and antifouling properties. The lowest-frequency resistance modulus of dual-layer superhydrophobic coating increases by two orders of magnitude compared with that of single superhydrophobic coating. Moreover, the coating still maintains superhydrophobicity under high/low temperatures (0–100 °C), acid/alkaline solution (pH = 1–14), drastic ultraviolet radiation (7 days), and mechanical wear (1600 cm). More importantly, the coating restores its superhydrophobicity several times after even in the face of extreme corrosive environments due to heating-driven migration of hydrophobic surfactants. Hence, the prepared self-healing superhydrophobic coating with mechanochemical stabilization has a bright prospect for anti-corrosion application under harsh service environments.

Zwitterionic surface modification of polyethylene via atmospheric plasma-induced polymerization of (vinylbenzyl-)sulfobetaine and evaluation of antifouling properties

Zwitterionic polymer brushes were grafted from bulk polyethylene (PE) by air plasma activation of the PE surface followed by radical polymerization of the zwitterionic styrene derivative (vinylbenzyl)sulfobetaine (VBSB). Successful formation of dense poly-(VBSB)-brush layers was confirmed by goniometry, IR spectroscopy, XPS and ToF-SIMS analysis. The resulting zwitterionic layers are about 50–100 nm thick and cause extremely low contact angles of 10° (water) on the material. Correspondingly we determined a high density of > 1.0 × 1016 solvent accessible zwitterions/cm2 (corresponding to 2,0 *10-8 mol/cm2) by a UV-based ion-exchange assay with crystal violet. The elemental composition as determined by XPS and characteristic absorption bands in the IR spectra confirmed the presence of zwitterionic sulfobetaine polymer brushes. The antifouling properties of the resulting materials were evaluated in a bacterial adhesion test against gram-positive bacteria (S. aureus). We observed significantly reduced cellular adhesion of the zwitterionic material compared to pristine PE. These microbiological tests were complemented by tests in natural seawater. During a test period of 21 days, confocal microscopy revealed excellent antifouling properties and confirmed the operating antifouling mechanism. The procedure reported herein allows the efficient surface modification of bulk PE with zwitterionic sulfobetaine polymer brushes via a scalable approach. The resulting modified PE retains important properties of the bulk material and has excellent and durable antifouling properties.

A Novel Zwitterionic Hydrogel Incorporated with Graphene Oxide for Bone Tissue Engineering: Synthesis, Characterization, and Promotion of Osteogenic Differentiation of Bone Mesenchymal Stem Cells.

Zwitterionic materials are widely applied in the biomedical field due to their excellent antimicrobial, non-cytotoxicity, and antifouling properties but have never been applied in bone tissue engineering. In this study, we synthesized a novel zwitterionic hydrogel incorporated with graphene oxide (GO) using maleic anhydride (MA) as a cross-linking agent by grafted L-cysteine (L-Cys) as the zwitterionic material on maleilated chitosan via click chemistry. The composition and each reaction procedure of the novel zwitterionic hydrogel were characterized via X-ray diffraction (XRD) and Fourier transformed infrared spectroscopy (FT-IR), while the morphology was imaged by scanning electron microscope (SEM). In vitro cell studies, CCK-8 and live/dead assay, alkaline phosphatase activity, W-B, and qRT-CR tests showed zwitterionic hydrogel incorporated with GO remarkably enhanced the osteogenic differentiation of bone mesenchymal stem cells (BMSCs); it is dose-dependent, and 2 mg/mL GO is the optimum concentration. In vivo tests also indicated the same results. Hence, these results suggested the novel zwitterionic hydrogel exhibited porous characteristics similar to natural bone tissue. In conclusion, the zwitterionic scaffold has highly biocompatible and mechanical properties. When GO was incorporated in this zwitterionic scaffold, the zwitterionic scaffold slows down the release rate and reduces the cytotoxicity of GO. Zwitterions and GO synergistically promote the proliferation and osteogenic differentiation of rBMSCs in vivo and in vitro. The optimal concentration is 2 mg/mL GO.

Recovery of Extracellular Polymeric Substances from Excess Sludge Using High-Flux Electrospun Nanofiber Membranes.

The recycling of extracellular polymeric substances (EPSs) from excess sludge in wastewater treatment plants has received increasing attention in recent years. Although membrane separation has great potential for use in EPS concentration and recovery, conventional membranes tend to exhibit low water flux and high energy consumption. Herein, electrospun nanofiber membranes (ENMs) were fabricated using polyvinylidene fluoride (PVDF) and used for the recovery of EPSs extracted from the excess sludge using the cation exchange resin (CER) method. The fabricated ENM containing 14 wt.% PVDF showed excellent properties, with a high average water flux (376.8 L/(m2·h)) and an excellent EPS recovery rate (94.1%) in the dead-end filtration of a 1.0 g/L EPS solution at 20 kPa. The ENMs displayed excellent mechanical strength, antifouling properties, and high reusability after five recycles. The filtration pressure had a negligible effect on the average EPS recovery rate and water flux. The novel dead-end filtration with an EPS filter cake on the ENM surface was effective in removing heavy-metal ions, with the removal rates of Pb2+, Cu2+, and Cr6+ being 89.5%, 73.5%, and 74.6%, respectively. These results indicate the potential of nanofiber membranes for use in effective concentration and recycling of EPSs via membrane separation.

Effect of phase disparity of MoS2 nanosheets on the performance of PES membranes for dual industrial oil-in-water emulsion separation and dyes adsorption

Water shortage is a global challenge due to increased demand and hence, reliable wastewater treatment avenues must be created to solve this problem. In this work, we report about the fabrication of dual performance polyethersulfone (PES) membranes modified with molybdenum disulfide (MoS2) nanosheets of different phases for wastewater remediation. We optimised process parameters to obtain large area, defect free membrane sheets. Comprehensive characterization revealed the phase disparity of MoS2, and changes introduced in the modified PES membranes. Blending MoS2 with PES membranes enhanced the mechanical properties as well as water uptake differently. The optimum PES membrane was modified with 0.2 wt% of 70% 1 T/2 H MoS2 and possessed superior pure water permeance of 778 kg/m2.h.bar. It also showed superior performance towards oil removal with rejection efficiency of 99% for 1 g/L oil concentration and it revealed excellent antifouling properties. The optimum membrane showed appreciable performance in organic dye rejection, even though it was outpaced by the 0.5 wt% of 70% 1 T/2 H MoS2 modified PES with a dye rejection of 98% towards methylene blue and 92% towards Rhodamine B. This work revealed that the phase of MoS2 strongly influences the structure and performance of the resultant PES-based nanocomposite membranes in ultrafiltration applications.

3D printing titanium dioxide-acrylonitrile-butadiene-styrene (TiO2-ABS) composite membrane for efficient oil/water separation

The oily water treatment is becoming one of the hottest topics due to that increase of offshore oil transportation and the various accident oil leakages. In this study, a functional TiO2-ABS composite membrane was generated through the three-dimensional (3D) printing strategy for the first time and was conducted to simulated oily water treatment. The TiO2-ABS composite membrane demonstrated a significant promotion in hydrophilicity and oleophobicity which were evidenced by the water contact angle of 14.8° and the underwater oil contact angle of 144.7°, respectively. The optimal modified membrane had both exceedingly high flux (1.8 × 105 L m−2·h−1) and oil rejection rate (99.5%). Moreover, the results of filtration cycles of 10 days and extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory demonstrated that the modified membranes took possession of excellent stability and antifouling property. What was more, the TiO2-ABS composite membrane revealed over 99% rejection to all five types of oil/water systems. The interestingly experimental results indicated that the prepared membrane possessed a broad development trend and application prospect in the field of oily water treatment.

Fabrication of S-PBI cation exchange membrane with excellent anti-fouling property for enhanced performance in electrodialysis

A novel anti-fouling cation exchange membrane (CEM) of sulfonated polybenzimidazole (S-PBI) was fabricated by the polymer bulk grafting modification of poly (4,4′-diphenyl ether-5,5′-bibenzimidazole) with sodium styrene sulfonate. FTIR, TGA, XPS, SEM and AFM were used to characterize membrane properties and the results showed that the ion exchange capacity and hydrophilicity of S-PBI increased with increased degrees of grafting and the electric resistance decreased accordingly. When the mass ratio of O-PBI/SSS was 1:4, the electric resistance of S-PBI-4.0 was 4.5 Ω·cm2, while the ion exchange capacity was 2.3 meq/g. The ED experiment with the S-PBI-4.0 membrane exhibited good desalination rate (>96 %), high current efficiency (80.73 %) and low energy consumption (1.13 kW·h/kg), which were very close to the results of a commercial CEM (Neosepta CMX). What's more, because of its good hydrophilicity, the S-PBI-4.0 membrane had better anti-fouling ability than Neosepta CMX, which was manifested as less resistance increase after membrane fouled by bovine serum albumin and smaller resistance after membrane cleaned by deionized water. These results demonstrate that the S-PBI-4.0 membrane is an appropriate candidate CEM and helpful to expand the application of ED in high-salinity organic industrial wastewater treatment.

Fully Superhydrophilic, Self-Floatable, and Multi-Contamination-Resistant Solar Steam Generator Inspired by Seaweed

• Independent floatability guarantees stable interfacial steam generation. • Complete hydration ensures superhydrophilicity and continuous water pumping. • High water affinity endows the floater with long-term multi-contamination resistance against oil spill, microbial corrosion, salt crystallization, protein adsorption, etc. • These merits allow the floater to perform stable solar evaporation from seawater or even wastewater. Highly hydrophilic materials enable rapid water delivery and salt redissolution in solar-driven seawater desalination. However, the lack of independent floatability inhibits heat localization at the air/water interface. In nature, seaweeds with internal gas microvesicles can float near the sea surface to ensure photosynthesis. Here, we have developed a seaweed-inspired, independently floatable, but superhydrophilic (SIFS) solar evaporator. It needs no extra floatation support and can simultaneously achieve continuous water pumping and heat concentration. The evaporator resists salt accumulation, oil pollution, microbial corrosion, and protein adsorption. Densely packed hollow glass microbeads promote intrinsic floatability and heat insulation. Superhydrophilic zwitterionic sulfobetaine hydrogel provides a continuous water supply, redissolves the deposited salt, and endows the SIFS evaporator with excellent anti-fouling properties. With its unprecedented anti-contamination ability, this SIFS evaporator is expected to open a new avenue for designing floatable superhydrophilic materials and solving real-world issues of solar steam generation in complex environmental conditions.

Potentiometric nanosensor for real-time measurement of hydrogen sulfide in single cell.

One potentiometric nanosensor for monitoring intracellular hydrogen sulfide (H2S) with fast potential response, high selectivity and excellent antifouling properties was developed. This study constructs a powerful tool to real-time track the changes of intracellular H2S in situ, promoting the future studies of physiologically relevant processes.

Biomimetic redox-responsive smart coatings with resistance-release functions for reverse osmosis membranes.

Membrane fouling induces catastrophic loss of separation performance and seriously restricts the applications of reverse osmosis (RO) membranes. Inspired by the mussel structure, polydopamine (PDA) and cystamine molecules (CA) with excellent anti-fouling properties were used to prepare accessible, biocompatible, and redox-responsive coatings for RO membranes. The PDA/CA-coated RO membranes exhibit a superior water flux of 65 L m-2 h-1 with a favourable NaCl rejection exceeding 99%. The water permeability through the PDA/CA-coated membrane is much higher than that of most membranes with similar rejection rates. Due to the formed protective hydration layers by PDA/CA coatings, anti-fouling properties against proteins, polysaccharides and surfactants were evaluated separately, and ultralow fouling properties were demonstrated. Moreover, the disulfide linkages in CA molecules can cleave in a reducing environment, yielding the degradation of PDA/CA coatings, thereby removing the foulants deposited on the coatings. The degradation endows the coated membranes with satisfying longtime anti-fouling properties, where the flux recovery reaches up to 90%. The construction of redox-responsive smart coatings not only provided a promising route to alleviate membrane fouling but can also be upscaled for use in numerous practical applications like sensors, medical devices, and drug delivery.

Exploration of advanced cellulosic material for membrane filtration with outstanding antifouling property.

Membranes, at times, have issues due to membrane fouling. The membrane fouling leads to performance deterioration and poses a potential to clog the membrane. Here we present experimental works carried out with emphasis on the antifouling properties, chlorine resistance, and mechanical properties of cellulose triacetate (CTA) and cellulose esters. We present that antifouling performance of cellulose esters evaluated by means of the VCG theory decreases with increasing carbon number in the substituent because of the high electron-donating nature of short aliphatic ester groups. When a long aliphatic ester group is required in terms of other properties such as resistance to chlorine, introducing it together with another substituent with an electron-donating nature such as an ethylene glycol moiety may strike a balance between antifouling and other performances.

Antifouling superhydrophilic porous glass membrane based on sulfobetaine prepared by thiol−ene click chemistry for high-efficiency oil/water separation

Compared to superhydrophobic/superoleophilic membranes for high-efficiency oil/water separation, superhydrophilic membranes displaying underwater superoleophobic properties show improved antifouling performance. Nevertheless, superhydrophilic/underwater superoleophobic surfaces reported so far, in general, are susceptible to oil contamination. In addition, the tricky fabrication methods towards the superhydrophilic membranes also severely limit practical applications of such materials. Herein, we prepared novel superhydrophilic/underwater superoleophobic porous glass membranes with excellent oil fouling resistance via one-step in situ growth of silicone nanofilament network layers on the surface of sand particle-based sintered glass filters using vinyltrichlorosilane (VTCS) as a precursor, followed by grafting of a thiol-functionalized of sulfobetaine by thiol-ene click chemistry. The sulfobetaine-modified porous glass membranes showed excellent underwater superoleophobicity even for viscous crude oil. Besides, such surface-modified glass membranes exhibited high efficiency for the separation of various oil-water mixtures (>99.992%) and oil-in-water emulsions (>99.968%), even for those involved with viscous crude oil (99.982%). Owing to its superior antifouling properties, the sulfobetaine-modified glass membranes display excellent reusability for the separation of oil-water mixtures and oil-in-water emulsions. The outstanding advantages with characteristics of easy-to-fabricate, low-cost, excellent antifouling properties, and high separation performance enable the sulfobetaine-modified porous glass membranes with great potential for oily sewage treatment.

Super-hydrophilic electrospun PAN nanofibrous membrane modified with alkaline treatment and ultrasonic-assisted PANI in-situ polymerization for highly efficient gravity-driven oil/water separation

Polyaniline (PANI) is utilized in numerous membrane-based oil/water emulsion separation systems due to its simple synthesis, low cost, chemical stability, and abundant amino functional groups. However, it is still challenging to benefit from the highest efficiency of the PANI-modified membrane in oil/water separation. Herein, PANI was favorably functionalized electrospun polyacrylonitrile (PAN) nanofiber through the establishment of electrostatic interaction and hydrogen bonding between aniline monomer and alkalinized PAN (APAN) nanofibers followed by aniline polymerization under ultrasonic irradiation (APAN/PANI-S) for high-performance oil/water emulsion separation. The uniform and efficient coating of PANI on APAN nanofiber led to the APAN/PANI-S nanofibrous membrane demonstrating outstanding physical stability in harsh acidic and basic conditions. In addition, the APAN/PANI-S nanofibrous membrane illustrated a super-hydrophilic and underwater super-oleophobic surface nature, which resulted in an extraordinary water flux of about 2289 LMH and oil rejection of around 99.69 % in oil/water separation under the gravity driving force. Furthermore, the homogenous penetration of PANI across the APAN nanofibrous membrane as a result of ultrasound-assisted polymerization caused the APAN/PANI-S nanofibrous membrane to show excellent mechanical stability (∼14.07 MPa) and antifouling properties (water flux of>981 LMH and oil rejection above 98 %) during 15-cycle oil/water emulsion separation. These results indicate that the APAN/PANI-S nanofibrous membrane with superior oil/water separation performance could be a promising candidate from a practical application point of view.

Evaluation of Intrinsic-Type and Hydrophobic Three-Dimensional Melamine/Polyvinyl-Alcohol Formaldehyde Sponges Containing a Hierarchical Porous Structure for Emulsion Separation

Emulsion separation of emulsified oil wastewater has been an urgent problem from both environmental and economic perspectives to be dealt with. Here, to overcome the emulsion separation material-prepared process involving expensive equipment and consuming large energy and the composite component-functionalized running off problem during application, a series of intrinsic-type and hydrophobically functionalized three-dimensional (3D) melamine/polyvinyl-alcohol formaldehyde (MF/PVF-Cn-x) sponges containing interpenetrating polymer networks (IPNs) and a hierarchical porous structure were synthesized by introducing a PVF network into a commercial melamine (MF) sponge by co-acetalation crosslinking reaction first and further acylating chlorination chemical grafting reactions. Water contact angles of as-prepared sponges were higher than 114.7°. Cross-sectional SEM morphological observation and pore size distribution curves demonstrated that interpenetrating polymer networks (IPN) and a hierarchical porous structure were constructed successfully. Their pore size scope was from 1 to 100 μm, and the average pore size was around 20 μm (15.7 and 25.1 μm), which was similar to a stable emulsion droplet size of 20 μm, which satisfied the size sieving requirement for emulsion separation. Compared with the separation performance of 2D membrane materials, MF/PVF-Cn-x 3D hierarchical porous materials exhibited excellent separation performance and antifouling property. Among them, the MF/PVF-C16-46.8% sponge had the most prominent emulsion separation performance with a flux of 9.55 × 104 L m–2 h–1 bar–1 and an efficiency of nearly 100%. Furthermore, the separation flux of MF/PVF-Cn-x was still higher than 2.22 × 104 L m–2 h–1 bar–1 and the efficiency was nearly 100% after seven cycles. On the other hand, the mechanical properties of MF/PVF-Cn-x sponges were strengthened by the introduced PVF network, and their compress stress was higher than 3.2 MPa. All the comprehensive performances made MF/PVF-Cn-x sponges become a suitable candidate as a highly effective emulsion separation material.

Anti-Oil-Adhesion Property of Superhydrophilic/Underwater Superoleophobic Phytic Acid-FeIII Complex Coatings

Crude oil adhesion issues are widespread in the petroleum industry, leading to inefficient production and high maintenance costs. Developing efficient antifouling materials and investigating the microscopic adhesion mechanism are of substantial significance. In the present work, a superhydrophilic/underwater superoleophobic PAFC coating with excellent antifouling properties was constructed by the coordination-driven self-assembly of phytic acid (PA) and FeCl3 (FC). The atomic force microscope (AFM) droplet probe technique was employed to elucidate the underlying mechanism of the anti-oil-adhesion property of the PAFC coating. Results showed that the PAFC modification achieved the optimum effect at a molar ratio of 1:3 between PA and FeIII. Applying a (3-aminopropyl)triethoxysilane (APTES) interlayer can effectively improve the performance of the PAFC coating on silica substrates. AFM droplet probe experiments indicated that the adhesion force between submerged micrometer-sized oil droplets and PAFC-modified substrates was significantly weaker than that with the untreated substrate. Meanwhile, the adhesion forces between oil droplets and surfaces were inversely proportional to the contact angle of the oil in water and were enhanced by higher salinity, lower collision velocity, and stronger loading force. The oil injection and wall sticking tests also confirmed the effectiveness of the PAFC modification in resisting the adhesion of crude oil.

Bio-Sourced and Biodegradable Membranes

Biodegradable membranes with innovative antifouling properties are emerging as possible substitutes for conventional membranes. These types of membranes have the potential to be applied in a wide range of applications, from water treatment to food packaging and energy production. Nevertheless, there are several existing challenges and limitations associated with the use of biodegradable membranes in large scale applications, and further studies are required to determine the degradation mechanisms and their scalability. Biodegradable membranes can be produced from either renewable natural resources or synthesized from low-molecular monomers that increase the number of possible structures and, as a result, greatly expand the membrane application possibilities. This study focused on bio-sourced and synthesized biodegradable polymers as green membrane materials. Moreover, the article highlighted the excellent antifouling properties of biodegradable membranes that assist in improving membrane lifetime during filtration processes, preventing chemical/biological disposal due to frequent cleaning processes and ultimately reducing the maintenance cost. The industrial and biomedical applications of biodegradable membranes were also summarized, along with their limitations. Finally, an overview of challenges and future trends regarding the use of biodegradable membranes in various industries was thoroughly analyzed.

High-performance PVDF water treatment membrane based on IL-Na+MMT for simultaneous removal of dyes and oil-water emulsions

In order to prepare a composite membrane which can remove both dye wastewater and oil-water emulsion Therefore, a PVDF/IL-Na+MMT membrane with excellent hydrophilic performance and antifouling properties was prepared by co-blending IL-Na+MMT with PVDF. The prepared modified membrane exhibited excellent hydrophilicity and lipophobicity, which can achieve high separation performance with PWF of 320.76 (L·m−2·h−1), excellent removal efficiency for both anionic and cationic dyes at a high level of over 90%, and superb rejection of oil-water emulsions. More interestingly, modified membranes have superior sustainability, with a FRR of 95.4% for anionic dyes, 88.3% for cationic dyes, and 95% for oil-water emulsions after two cycle tests. PVDF/IL-Na+MMT membrane is a good reference in solving the practical application problems of treating oil-water emulsion and dye wastewater.