Membranes For Water Treatment Research Articles

Characterizing Macroporous Ion Exchange Membrane Adsorbers for Natural Organic Matter (NOM) Removal—Adsorption and Regeneration Behavior

Addressing the characterization of Natural Organic Matter (NOM) removal by functionalized membranes in water treatment, this study evaluates the effectiveness of two commercial ion-exchange membrane adsorbers: Sartobind® Q (with quaternary amines) and D (with tertiary amines). Using Suwannee River NOM (SRNOM) as a surrogate, Langmuir adsorption isotherms revealed maximum capacities (Qmax) of 2966 ± 153 mg C/m2 and 2888 ± 112 mg C/m2, respectively. Variations in flux from 50 to 500 LMH had a minimal impact on breakthrough times, proving low diffusion limitations. The macroporous (3–5 µm) functionalized cellulose-based membranes exhibited high permeabilities of 10800 L/(h m2 bar). Q maintained positive zeta potential vs. pH, while D’s zeta potential decreased above pH 7 due to amine deprotonation and turning negative above an isoelectric point of 9.1. Regeneration with 0.01 M NaOH achieved over 95% DOC regeneration for Sartobind® D, characterizing reversibility through a pH-swing. Cyclic adsorption showed that Q maintained its capacity with over 99% DOC regeneration, while D required acidic conditioning after the first regeneration cycle to mitigate capacity reduction and re-deprotonate the adsorber. These results have demonstrated the potential suitability of adsorber membranes, designed originally for biotechnological purposes, for the possible removal of disinfection byproduct precursors in drinking water treatment.

Carboxylic acid modulated in situ growth of Zr-based MOFs on carboxylated cotton fabrics for removal of Cr(VI) from aqueous solutions

In this paper, carboxylated cotton fabric (CF-Ph-COOH) were obtained as active substrate by diazonium radical polymerization modification of cotton fibers. Then the MOF fabric composites were prepared by in situ growth of metal zirconium ions (Zr) and organic ligands on the surface of carboxylated cotton fabrics under carboxylic acid modifier. MOF fabric composites with controllable morphologies structures were achieved by regulating organic ligands, reaction time the type and dosage of regulator (formic acid and acetic acid). The prepared acetic acid regulated MOF fabric composites were designated as CF-HAc1-UiO-66, CF-HAc2-UiO-66, CF-HAc1-UiO-66-NH2, and CF-HAc2-UiO-66-NH2, respectively, and the formic acid regulated as CF-FA-UiO-66 and CF-FA-UiO-66-NH2. The fabricated carboxylic acid modulated MOF fabric composites were well characterized using SEM, TGA, XRD, FTIR, and XPS spectra. The adsorption experiment results show that carboxylic acid modulated Zr based MOF fabric composites can serve as adsorbent for effective removal of Cr(VI) from water, in which the CF-FA-UiO-66-NH2 was prepared under the ratio of ZrCl4 and BDC-NH2 is 1.006 and with 5.47 M formic acid regulator exhibits that the optimal adsorption efficiency and the removal efficiency is 79.5 %. In addition, the adsorption of Cr(VI) in water by CFA-UiO-66-NH2 showed a quasi-secondary kinetic model following the Langmuir adsorption model, showing a a typical of chemisorption. What’s more, the Cr(VI) removal efficiency and saturated adsorption capacity of CF-FA-UiO-66-NH2 was up to 80 % and 318.85 mg/g, respectively. The prepared CF-FA-UiO-66-NH2 MOF fabric composite was recyclable for removal of Cr(VI), and could be used as the potential adsorbent membrane for waste water treatment.

Catalytic membranes assembled by Co–Fe Prussian blue analogues functionalized graphene oxide nanosheets for rapid removal of contaminants

The catalytic membrane, combining confinement effect with advanced oxidation processes, exhibits great potential as an efficient technology for removing contaminants and mitigating membrane fouling. Herein, the Prussian blue analogues (PBAs) functionalized graphene oxide (GO) membranes, referred as PGMs, was successfully fabricated. It exhibited a package-like confined structure where Co–Fe PBAs were encapsulated within interconnected GO nanosheets. The surface properties, internal structure as well as the catalytic performance of PGMs were controlled by adjusting the amount of Co–Fe PBAs anchored on GO nanosheets. The designed PGM as efficient peroxymonosulfate activator exhibited exceptional catalytic performance, achieving complete removal of bisphenol A (BPA) with a retention time of 31 ms. The corresponding first-order rate constant was 6000 min−1, which surpassed conventional batch system by four orders of magnitude (0.2194 min−1). Moreover, the redox cycle involving Fe2+ and Co3+, coupled with the effective suppression of ion leaching from Co–Fe PBAs nanoparticles (<10 μg/L) through GO protective layers, ensured the stable catalytic performance of PGM over 144 h. This study employs a novel approach to confine catalytic nanoparticles within two-dimensional nanosheets, demonstrating the potential applications of the resulting confined membrane in water treatment.

Mo-BiVO4 Photocatalytically Modified Ceramic Ultrafiltration Membranes for Enhanced Water Treatment Efficiency.

This study highlights the effectiveness of photocatalytically modified ceramic ultrafiltration (UF) membranes in alleviating two major drawbacks of membrane filtration technologies. These are the generation of a highly concentrated retentate effluent as a waste stream and the gradual degradation of the water flux through the membrane due to the accumulation of organic pollutants on its surface. The development of two types of novel tubular membranes, featuring photocatalytic Mo-BiVO4 inverse opal coatings, demonstrated a negligible impact on water permeance, ensuring consistent filtration and photocatalytic efficiency and suggesting the potential for maintaining membrane integrity and avoiding the formation of highly concentrated retentate effluents. Morphological analysis revealed well-defined coatings with ordered domains and interconnected macropores, confirming successful synthesis of Mo-BiVO4. Raman spectroscopy and optical studies further elucidated the composition and light absorption properties of the coatings, particularly within the visible region, which is vital for photocatalysis driven by vis-light. Evaluation of the tetracycline removal efficiency presented efficient adsorption onto membrane surfaces with enhanced photocatalytic activity observed under both UV and vis-light. Additionally, vis-light irradiation facilitated significant degradation, showcasing the versatility of the membranes. Total Organic Carbon (TOC) analysis corroborated complete solute elimination or photocatalytic degradation without the production of intermediates, highlighting the potential for complete pollutant removal. Overall, these findings emphasize the promising applications of Mo-BiVO4 photocatalytic membranes in sustainable water treatment and wastewater remediation processes, laying the groundwork for further optimization and scalability in practical water treatment systems.

Electrochemically produced nano-TiO2-coated SiC membranes for photocatalytic water treatment: Preparation, characterization, and hydroxyl radical formation

ABSTRACT Photocatalytically active ceramic flat sheet membranes based on a nanostructured titanium dioxide (TiO2) coating were produced for photocatalytic water treatment. The nano-TiO2 layer was produced by a novel combination of magnetron sputtering of a thin titanium layer on silicon carbide (SiC) membranes, followed by electrochemical oxidation (anodization) and subsequent heat treatment. Characterization by Raman spectra and field emission scanning electron microscopy proved the presence of a nanostructured anatase layer on the membranes. The influence of the titanium layer thickness on the TiO2 formation process and the photocatalytic properties were investigated using anodization curves, by using cyclovoltammetry measurements, and by quantifying the generated hydroxyl radicals (OH•) under UV-A irradiation in water. Promising photocatalytic activity and permeability of the nano-TiO2-coated membranes could be demonstrated. A titanium layer of at least 2 μm was necessary for significant photocatalytic effects. The membrane sample with a 10 μm Ti/TiO2 layer had the highest photocatalytic activity showing a formation rate of 1.26 × 10−6 mmol OH• s−1. Furthermore, the membranes were tested several times, and a decrease in radical formation was observed. Assuming that these can be attributed to adsorption processes of the reactants on the TiO2 surface, initial experiments were carried out to reactivate the photocatalyzer.

Machine-Learning-Aided Understanding of Protein Adsorption on Zwitterionic Polymer Brushes.

Constructing antifouling surfaces is a crucial technique for optimizing the performance of devices such as water treatment membranes and medical devices in practical environments. These surfaces are achieved by modification with hydrophilic polymers. Notably, zwitterionic (ZI) polymers have attracted considerable interest because of their ability to form a robust hydration layer and inhibit the adsorption of foulants. However, the importance of the molecular weight and density of the ZI polymer on the antifouling property is partially understood, and the surface design still retains an empirical flavor. Herein, we individually assessed the influence of the molecular weight and density of the ZI polymer on protein adsorption through machine learning. The results corroborated that protein adsorption is more strongly influenced by density than by molecular weight. Furthermore, the distribution of predicted protein adsorption against molecular weight and polymer density enabled us to determine conditions that enhanced (or weaken) antifouling. The relevance of this prediction method was also demonstrated by estimating the protein adsorption over a wide range of ionic strengths. Overall, this machine-learning-based approach is expected to contribute as a tool for the optimized functionalization of materials, extending beyond the applications of ZI polymer brushes.

Recent Advances in Water Treatment Membranes Based on Nanomaterials (A Review)

Nanomaterials have emerged as the next generation of materials for high-performance water treatment membranes, with the ability to address the global problem of pollution in water. Application of nanoparticles as membranes improves permeability feature for water, mechanical performance, efficiency of separation, and membrane fouling. As a result, the nanomaterials open up a new avenue for effectively selective membranes for purification of the water. This paper discusses the enhancements in membrane caused by the presence of various nanomaterials, such as nanoparticles (NPs), two-dimensional nano-materials (2D), nanofibers, nanosheets, and other nano-composite structure materials. Furthermore, the many uses of these membranes-based nanoparticles in treatment of water applications are emphasized. The goal is to show how important nanoparticles are in the membrane manufacturing in treatment of water. Nanomaterials and nanotechnology were discovered to have enormous promise for the progress of sustainable treatment of water and its wastes.

Reactive layered hydroxide membrane for advanced water treatment: Micropollutant degradation and antifouling potential

The effective removal of micropollutants by water treatment technologies remains a significant challenge. Herein, we develop a CoFe layered double hydroxide (CoFeLDH) catalytic membrane for peroxymonosulfate (PMS) activation to achieve efficient micropollutant removal with improved mass transfer rate and reaction kinetics. This study found that the CoFeLDH membrane/PMS system achieved an impressive above 98% degradation of the probe chemical ranitidine at 0.1 mM of PMS including five more micropollutants (Sulfamethoxazole, Ciprofloxacin, Carbamazepine, Acetaminophen and Bisphenol A) at satisfactory level (above 80%). Moreover, significant improvements in water flux and antifouling properties were observed, marking the membrane as a specific advancement in the removal of membrane fouling in water purification technology. The membrane demonstrated consistent degradation efficiency for several micropollutants and across a range of pH (4–9) as well as different anionic environments, thereby showing it suitability for scale-up application. The key role of reactive species such as SO4•–, and O2• − radicals in the degradation process was elucidated. This is followed by the confirmation of the occurrence of redox cycling between Co and Fe, and the presence of CoOH+ that promotes PMS activation. Over the ten cycles, the membrane could be operated with a flux recovery of up to 99.8% and maintained efficient performance over 24 h continuous operation. Finally, the efficiency in degrading micropollutants, coupled with reduced metal leaching, makes the CoFeLDH membrane as a promising technology for application in water treatment.

Electrochemical Detection of Selective Anion Transport through Subnanopores in Liquid-Crystalline Water Treatment Membranes.

The anion-selective transport through subnanoporous liquid-crystalline (LC) water treatment membranes was quantitatively detected by the deposition and electrochemical analysis of the LC membrane on the GaN electrode. The time course of the capacitance and Warburg resistance of the LC membrane suggest that the interaction of the LC membrane with monovalent Cl- ions is distinctly different from that with SO42- ions. A continuous decay in capacitance suggests the condensation of Cl- ions in subnanopores, whereas the interaction between SO42- ions and the inner wall of subnanopores is much weaker. The chronoamperometry data further suggest that SO42- ions are transported through subnanoporous channels 10 times faster than Cl- ions. These results, together with the previous X-ray emission spectroscopy, suggest that SO42- ions, which possess similar hydrogen-bonded structures to the hydrogen-bonded networks inside the subnanopores, can exchange the associated water molecules and hop along the network of water molecules, but Cl- ions bind and accumulate inside subnanopores. The well-controlled supramolecular self-assembly of LC building blocks opens a large potential toward the fine adjustment of hydrogen-bonding networks in nanospace providing materials new functions, which cannot be realized by bulk water.

Leveraging tannic acid-ferric iron (TA/Fe3+) complexation in polyamide selective layer for synthesizing robust thin film composite reverse osmosis (TFC-RO) hollow fiber membranes for saline water treatment

The high efficiency and adaptability of reverse osmosis (RO) are two main reasons this separation technology is accepted worldwide, depending on its various uses, such as water purification, desalination, and concentration. The potential of RO can be enhanced by utilizing the hollow fiber (HF) mode, benefiting from higher packing density, ease of cleaning, and cost competitiveness. However, its suitability for RO applications becomes questionable due to its weaker and fragile mechanical resilience. To solve the abovementioned issue and improve the mechanical strength and burst/crush pressure, we propose optimizing the selective layer of the TFC-RO membrane using tannic acid complexation with FeCl3. The polyethersulfone (PES) support layer was initially fabricated to host the polyamide (PA) layer. Subsequently, the introduction of tannic acid-ferric chloride complexation was implemented as a sandwich layer between the aqueous and organic phase reactions to host a coherent and selective PA layer to further enhance its performance by controlling the kinetics of interfacial polymerization (IP). The surface morphology, physicochemical properties, and underlying reactions were analyzed using scanning electron microscopy (SEM), atomic force microscope (AFM), Fourier infrared spectroscopy (FTIR), x-ray photoelectron spectroscopy (XPS), and water contact angle measurements. The TFC-RO membrane M_TA0.2/Fe7.5 (7.5 mM FeCl3 & 0.2 wt% tannic acid) showed significant improvement in pure water permeance and salt rejection along with 7.23 MPa of burst pressure and 68.41 % strain, which proves superior elasticity and mechanical robustness because of PA TA/Fe3+ complexes formed during the IP. Moreover, the proposed facile tannic acid modification is effective and scalable. It significantly improves the mechanical efficacy of the HF TFC-RO membrane, solving a great problem for its commercial adaptability for RO applications and paving the way for smoother industrial translation for direct human factor applications.

MAO-DBN based membrane fouling prediction

Due to the complexity of the factors influencing membrane fouling in membrane bioreactors (MBR), it is difficult to accurately predict membrane fouling. This paper proposes a multi-strategy of integration aquila optimizer deep belief network (MAO-DBN) based membrane fouling prediction method. The method is developed to improve the accuracy and efficiency of membrane fouling prediction. Firstly, partial least squares (PLS) are used to reduce the dimensionality of many membrane fouling factors to improve the algorithm’s generalization ability. Secondly, considering the drawbacks of deep belief network (DBN) such as long training time and easy overfitting, piecewise mapping is introduced in aquila optimizer (AO) to improve the uniformity of population distribution, while adaptive weighting is used to improve the convergence speed and prevent falling into local optimum. Finally, the prediction of membrane fouling is carried out by utilizing membrane fouling data as the research object. The experimental results show that the method proposed in this paper can achieve accurate prediction of membrane fluxes, with an 88.45% reduction in RMSE and 87.53% reduction in MAE compared with the DBN model before improvement. The experimental results show that the model proposed in this paper achieves a prediction accuracy of 98.61%, both higher than other comparative models, which can provide a theoretical basis for membrane fouling prediction in the practical operation of membrane water treatment.

Innovations in nanomaterial-embedded polymer membranes for water and wastewater treatment: a comprehensive review

Abstract There has been growing interest in advancing nanoparticle-embedded polymeric membranes and their significant utilization in wastewater treatment to address the global water pollution problem. Incorporation of nanomaterials into the membrane matrices not only enhances the physicochemical properties like hydrophilicity, mechanical and thermal stability, porosity, antifouling, and antibacterial properties of the polymers but also influences the membrane permeability, selectivity, and several contaminant removals. This overview highlighted the development of nanomaterials like metal/metal oxide nanoparticles (0D), carbon nanotubes (1D), graphene or graphene oxide (GO) (2D layer materials), zwitterionic, zeolites, and associated structures (3D) blended with significant polymeric materials, along with synthesis and integration techniques for fabricating mixed-matrix nanoparticle-embedded polymer nanocomposite (PNC) membranes. This article also addresses the limitations of conventional water treatment technologies, recent challenges of polymer membrane technology, environmental impact, human considerations, and the prospects of these advanced nanoparticle-embedded polymer membranes for sustainable water and wastewater treatment. The motivation for future research in polymeric materials with embedded nanoparticles and the prediction of novel membranes for water purification will also be provided.

Synergy of Ligands in Tailoring the Photocatalytic Properties of Zirconium Metal–Organic Framework-Impregnated Membranes for Water Treatment

Synergy of Ligands in Tailoring the Photocatalytic Properties of Zirconium Metal–Organic Framework-Impregnated Membranes for Water Treatment

Progressive Insights into Metal-Organic Frameworks and Metal-Organic Framework-Membrane Composite Systems for Wastewater Management.

The sustainable management of wastewater through recycling and utilization stands as a pressing concern in the trajectory of societal advancement. Prioritizing the elimination of diverse organic contaminants is paramount in wastewater treatment, garnering significant attention from researchers worldwide. Emerging metal-organic framework materials (MOFs), bridging organic and inorganic attributes, have surfaced as novel adsorbents, showcasing pivotal potential in wastewater remediation. Nevertheless, challenges like limited water stability, elevated dissolution rates, and inadequate hydrophobicity persist in the context of wastewater treatment. To enhance the performance of MOFs, they can be modified through chemical or physical methods, and combined with membrane materials as additives to create membrane composite materials. These membrane composites, derived from MOFs, exhibit remarkable characteristics including enhanced porosity, adjustable pore dimensions, superior permeability, optimal conductivity, and robust water stability. Their ability to effectively sequester organic compounds has spurred significant research in this field. This paper introduces methods for enhancing the performance of MOFs and explores their potential applications in water treatment. It delves into the detailed design, synthesis strategies, and fabrication of composite membranes using MOFs. Furthermore, it focuses on the application prospects, challenges, and opportunities associated with MOF composite membranes in water treatment.

Enhanced Separation Performance of Graphene Oxide Membrane through Modification with Graphitic Carbon Nitride

The treatment of tritiated nuclear wastewater is facing greater challenges with the continuous expansion of the nuclear industry. The key to solving the issue of detritium in low-abundance tritium water lies in developing highly efficient and cost-effective hydrogen isotope separation technology. Graphene oxide (GO) membrane separation method exhibits greater potential compared to other existing energy-intensive technologies for the challenging task of hydrogen isotope separation in nuclear wastewater. In recent years, researchers have explored few strategies to enhance the performance of graphene oxide (GO) membranes in hydrogen isotope water treatment, recognizing the current limitations in separation efficiency. In this study, the GO/g-C3N4 composite membrane has been successfully employed for the first time in the separation of hydrogen isotopes in water. A series of GO membranes were prepared and their performances were tested by a self-made experimental device. As a result, the separation performance of the GO membrane was enhanced by the modification with graphitic carbon nitride (g-C3N4). The permeation rate of the GO/g-C3N4 membrane was higher than that of the GO membrane, while maintaining a high separation factor. Our study also demonstrated that this phenomenon can be attributed to the changes in membrane structure at the microscopic scale. The H/D separation factor and the permeate flux of the composite membrane containing g-C3N4 of 6.7% by mass were 1.10 and 7.2 × 10−5 g·min−1·cm−2 are both higher than that of the GO membrane under the same experimental conditions, which is promising for the isotope treatment.

Role of plasma process gas on permeate flux augmentation of cellulose nitrate membrane for mud water treatment

A comparative study between Nitrogen (N2) and Argon (Ar) plasma is carried out to investigate its effect on surface morphology, hydrophilicity, permeate flux and ageing of cellulose nitrate polymeric membranes in the present work. Langmuir probe and Optical Emission Spectroscopy are used to characterize the plasma. The SEM analysis reveals the noticeable macro-void creations and pore enlargement for both N2 and Ar plasma. The AFM analysis shows a higher surface roughness for Ar plasma treatment as compared to N2 plasma treatment. XPS analysis confirms the changes in the polymer matrix along with the incorporation of various functional groups on the membrane surface as a result of the plasma treatment. A better hydrophilic nature with prolonged plasma treatment is observed for Ar plasma as compared to N2 plasma treatment. The present results show a higher permeate flux with a high rejection rate for Ar plasma treatment in comparison to N2 plasma, which might be due to the pore size and pore area enlargement of the membrane. The hydrophobic recovery for both the plasma-treated membranes is found significant for the initial ageing period of 7 days and found almost stable in nature after 7 days. A diffusion-based theoretical model is developed to study the hydrophobic recovery of plasma-treated membranes. A strong alignment between experimental and theoretical results is observed in the present work. The Cake Filtration model, derived from the Hermia model, is identified as the most suitable model for describing the fouling mechanisms for the present work.

A novel hydrophilic modification method for polytetrafluoroethylene (PTFE) hollow fiber membrane using sacrificial template

In order to enhance the hydrophilicity of PTFE hollow fiber membrane, high concentration of polymer was needed during the modifying process, but this method resulted in severe pore blockage of hollow fiber membrane with reduced water flux. Herein, we resolve the above contradiction by using cross-linkable poly (vinylpyrrolidone-co-γ-methacryloxypropyltrimethoxysilane) (P (VP-co-KH570)) as hydrophilic polymer and calcium chloride as sacrificial template. The enhanced hydrophilicity and chemical washing resistance of PTFE hollow fiber membrane were achieved by the highly hydrophilic PVP segments and highly crosslinking density contributed by hydrolysis and condensation of the KH570 segments, respectively. The template is embedded in the polymer network formed in the membrane pores, and after template removal the previously occupied pores are released for water transport, thereby minimizing the loss of water flux. The high water flux (1477.14 ± 16.11 L/(m2·h)), superhydrophilicity (the water contact angle = 0°) and hydrophilic stability proved that PTFE hollow fiber membranes are successfully modified by the sacrificial template method. This work provides a facile strategy for designing hydrophilic PTFE hollow fiber membranes for water treatment.

Designing Sustainable Hydrophilic Interfaces via Feature Selection from Molecular Descriptors and Time-Domain Nuclear Magnetic Resonance Relaxation Curves.

Surface modification using hydrophilic polymer coatings is a sustainable approach for preventing membrane clogging due to foulant adhesion to water treatment membranes and reducing membrane-replacement frequency. Typically, both molecular descriptors and time-domain nuclear magnetic resonance (TD-NMR) data, which reveal physicochemical properties and polymer-chain dynamics, respectively, are required to predict the properties and understand the mechanisms of hydrophilic polymer coatings. However, studies on the selection of essential components from high-dimensional data and their application to the prediction of surface properties are scarce. Therefore, we developed a method for selecting features from combined high-dimensional molecular descriptors and TD-NMR data. The molecular descriptors of the monomers present in polyethylene terephthalate films were calculated using RDKit, an open-source chemoinformatics toolkit, and TD-NMR spectroscopy was performed over a wide time range using five-pulse sequences to investigate the mobility of the polymer chains. The model that analyzed the data using the random forest algorithm, after reducing the features using gradient boosting machine-based recursive feature elimination, achieved the highest prediction accuracy. The proposed method enables the extraction of important elements from both descriptors of surface properties and can contribute to the development of new sustainable materials and material-specific informatics methodologies encompassing multiple information modalities.

The mitigation potential of synergistic quorum quenching and antibacterial properties for biofilm proliferation and membrane biofouling

Biofouling has been a persistent problem hindering the application of membranes in water treatment, and quorum quenching has been identified as an effective method for mitigating biofouling, but surface accumulation of live bacteria still induces biofilm secretion, which poses a significant challenge for sustained prevention of membrane biofouling. In this study, we utilized quercetin, a typical flavonoid with the dual functions of quorum quenching and bacterial inactivation, to evaluate its role in preventing biofilm proliferation and against biofouling. Quercetin exhibited excellent antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), and the decreased bioactivity was positively correlated with the quercetin concentration, with inhibition rates of 53.1 % and 57.4 %, respectively, at the experimental concentrations. The RT-qPCR results demonstrated that quercetin inhibited AI-2 of E. coli and AGR of S. aureus mediated quorum sensing system, and reduced the expression of genes such as adhesion, virulence, biofilm secretion, and key regulatory proteases. As a result, the bacterial growth cycle was retarded and the biomass and biofilm maturation cycles were alleviated with the synergistic effect of quorum quenching and antibacterial activity. In addition, membrane biofouling was significantly declined in the dynamic operation experiments, dead cells in the biofilm overwhelmingly dominated, and the final normalized water fluxes were increased by more than 49.9 % and 34.5 % for E. coli and S. aureus, respectively. This work demonstrates the potential for mitigating biofouling using protocols that quorum quenching and inactivate bacteria, also provides a unique and long-lasting strategy to alleviate membrane fouling.

Machine learning – Driven surface grafting of thin-film composite reverse osmosis (TFC-RO) membrane

Modifying reverse-osmosis (RO) membrane performance is challenging and time-consuming due to the complex interplay of various factors that influence the membrane's performance. To address this challenge, we have explored the potential of using machine-learning (ML) to graft the polyamide (PA) surface of an RO membrane to increase water permeability and overcome the limitations of the permeability/selectivity tradeoff. We identified moieties with positive and negative contributions toward water permeability by applying Shapley-Additive-exPlanations (SHAP) analysis to our model as an explainable artificial intelligence (XAI) method. We attempted to improve the subunits of the PA's structure with positive Shapley values and graft the polyamide RO membrane layer of a commercial membrane, Dupont XLE, resulting in a substantial increase in water permeability. The membranes were characterized using FTIR, EDS, and SEM analysis, and their performance was evaluated for water permeance and NaCl rejection using a dead-end stirred cell. The modified membrane exhibited a significant improvement in the commercial membrane's water flux, increasing from 2.45 LMH to 4.9 LMH. Our results demonstrate the potential of using ML to replace traditional trial-and-error methods for modifying PA-RO membrane polyamide layers and advancing the development of higher efficient and sustainable RO membranes for water treatment and purification applications.