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In this study, hematite graphene oxide (αFe2O3-GO) powder nanocomposites and thin-film hematite graphene oxide (αFe2O3-GO) were synthesized for application in the removal of Rhodamine B (RhB) from textile wastewater. αFe2O3-GO nanomaterials were placed onto the FTO substrate to form a thin layer of nanocomposites. Different analysis including XRD, FTIR, Raman spectra, XPS, and FESEM were done to analyze the morphology, structure, and properties of the synthesized composites as well as the chemical interactions of αFe2O3 with GO. The photocatalytic performance of two synthesized composites was compared with different concentrations of αFe2O3-GO. The results showed that powder nanocomposites are more effective than thin-film composites for the removal of RhB dye. αFe2O3-GO-5% powder nanocomposites removed over 64% of dye while thin-film nanocomposites had less removal efficiencies with just under 47% removal rate. The reusability test was done for both materials in which αFe2O3-GO-5% powder nanocomposites removed a higher rate of dye (up to 63%) in more cycles (6 cycles). [ABSTRACT FROM AUTHOR]

Incorporation of nanomaterials into the thin film composite (TFC) membrane is a promising approach to enhance the filtration performance of the membranes. This study was aimed to fabricate a novel thin film nanocomposite (TFN) membrane hybridized with hollow mesoporous silica nanoparticles (HMSN). It was expected that the HMSN-TFN membranes could have enhanced desalination performance. The research was focused on understanding of how the HMSN incorporation could affect physicochemical properties and permeation behavior of the HMSN-TFN membranes. Spherical HMSN with an average particle size of ~70 nm were fabricated by hydrothermal synthesis using soft templates. The HMSN were successfully incorporated into the selective polyamide layer in the TFN structures. The physicochemical properties of the HMSN and TFN membranes were systematically investigated using DLS, TGA, ATR-FTIR, SEM, TEM, nitrogen sorption analyser, tensiometer and XPS analysis. The HMSN-TFN membranes were more hydrophilic and performed highly improved water flux (~40%) compared with the TFC membranes, while their rejection to NaCl was not significantly changed. The HMSN-TFN membranes also displayed a higher compaction resistance than the TFC membrane, suggesting a positive interaction between the HMSN and the polyamide thin film layer. This interaction is beneficial for enhancing the strength and durability of the newly developed HMSN-TFN membranes in the high-pressure filtration process. [ABSTRACT FROM AUTHOR]

Thin film composite (TFC) membranes are the most commonly used polymeric membranes in desalination process. The membrane properties and performance are dominated by many fabrication parameters, including chemistry of polymers and synthesis conditions. This study was aimed to develop an integrated statistic-systematic approach to study the correlation between fabrication condition and desalination performance of the TFC membranes. Three key fabrication factors: polysulfone concentration, aqueous phase soaking time and heat curing time were statistically analysed to determine their optimal values and interactional influence on desalination performance. The desalination performance was systematically evaluated based on permeate flux and salt rejection. It is expected that statistic results can facilitate the understanding of synthesis-performance correlations of TFC membranes. Two mathematical models for correlating fabrication factors with permeate flux and salt rejection were developed. The most influential correlations were identified as the polysulfone concentration - permeate flux and soaking time - salt rejection. Interaction of soaking time with polysulfone concentration and curing time was determined to have significant impact on the salt rejection. Our findings highlighted the importance of considering interactions between the fabrication conditions and desalination performance when devising a strategy to fabricate TFC membranes for maximising desalination performance. [ABSTRACT FROM AUTHOR]

Thin film composite (TFC) polyamide membranes have been predominantly utilized in water treatment and desalination and play a significant role in the separation processes. However, the occurrence of fouling, especially biofouling, has a detrimental effect on the efficiency of the membrane. The introduction of nanostructures and other surface modification strategies has paved the way for developing antibacterial TFC membranes, aiming to control and mitigate biofouling to achieve a rational design for practical applications. This comprehensive review introduces and discusses novel antibacterial TFC membranes, including their structure, composition, and performance. Additionally, particular attention is given to understanding the antibacterial mechanism of nanomaterials. To this end, various emerging and prevalent antibacterial nanomaterials are introduced, and their role in the fabrication of TFC membranes is overviewed. Moreover, versatile modification strategies are outlined to impart antibacterial activity into TFC membranes. Finally, the review proposes current challenges and prospects of antibacterial TFC membranes, aiming to provide valuable insights for developing advanced TFC membranes with optimal resistance against biofouling and improved separation performance. This critical review serves as a fundamental guide for designing strategies that surpass the current limitations of TFC membranes' antibacterial agents and nanomaterials, thereby mitigating the tendency of biofouling through tailored membrane surface properties. [Display omitted] • Explores biofouling complexities; implications discussed • Strategies for antimicrobial activity; enhance antibiofouling • Summarizes antibacterial agents; focusing on control mechanisms • Explores TFC membrane modification for antibacterial activity • Versatile applications of antibacterial TFC membranes and elaborates on challenges and future prospects [ABSTRACT FROM AUTHOR]

The recent advancements in fabricating forward osmosis (FO) membranes have shown promising results in desalination and water treatment. Different methods have been applied to improve FO performance, such as using mixed or new draw solutions, enhancing the recovery of draw solutions, membrane modification, and developing FO-hybrid systems. However, reliable methods to address the current issues, including reverse salt flux, fouling, and antibacterial activities, are still in progress. In recent decades, surface modification has been applied to different membrane processes, including FO membranes. Introducing nanochannels, bioparticles, new monomers, and hydrophilic-based materials to the surface layer of FO membranes has significantly impacted their performance and efficiency and resulted in better control over fouling and concentration polarization (CP) in these membranes. This review critically investigates the recent developments in FO membrane processes and fabrication techniques for FO surface-layer modification. In addition, this study focuses on the latest materials and structures used for the surface modification of FO membranes. Finally, the current challenges, gaps, and suggestions for future studies in this field have been discussed in detail. [Display omitted] • The existing challenges in traditional forward osmosis (FO) membranes are discussed. • Surface modification of FO membranes (e.g., surface grafting and coating) are evaluated. • Remarkable flux improvements (ranging from 17% to 80%) have been reported for surface modified FO membranes. • Novel additives and biomimetic membranes are evaluated for FO membranes' surface tailoring. • The influence of nanochannels on the performance of FO membranes is investigated. [ABSTRACT FROM AUTHOR]

With the gradual increase of microplastics (MPs) in water and wastewater streams, it is imperative to investigate their removal using tertiary treatment systems to minimize and preferably prevent their entrance into aquatic environments. Forward osmosis (FO) is a non-pressurized membrane process with potential applications in MPs removal from wastewater. However, efficient application of FO systems relies on developing high-performance FO membranes with low fouling tendency. MPs are proven as emerging foulants in membrane systems, diminishing their performance and lifetime and this highlights the need to consider MP fouling in developing sustainable membranes. The current study focuses on a novel modification of thin film composite (TFC) FO membranes by MIL-53(Fe) as a water-stable and hydrophilic metal-organic framework. Experimental results demonstrated that the optimized FO membrane (0.2 wt% MIL-53(Fe)) achieved a significantly higher water flux (90% increase) with a 23% less reverse salt flux. The modified membrane also had significantly less flux decline in fouling experiments and higher flux recovery after physical cleaning compared to the control membrane affirming its higher antifouling efficiency. MIL-53(Fe) integration in the FO substrate proved to be a practical method for developing high-performance TFC FO membranes with improved antifouling properties against MPs and organic foulants. [Display omitted] • MIL-53(Fe) incorporation into TFC FO substrate enhanced the membranes' performance. • MIL-53(Fe) improved the hydrophilicity and porosity of the FO substrate. • TFC on the developed substrate had higher water flux and lower specific salt flux. • The modified membrane showed better microplastic antifouling properties. • MIL-53 modification improved the membranes' organic fouling resistance. [ABSTRACT FROM AUTHOR]

Thin film composite (TFC) membranes have been experiencing significant modifications recently aiming to improve their structure, properties and separation efficiency. One of the promising modifications to tailor the membranes more efficient is changing the materials used. m -phenylene diamine (MPD), piperazine (PIP), and trimesoyl chloride (TMC) are the most common monomers used to fabricate TFC membranes. Recent studies have introduced several alternatives to these traditional monomers showing significant contribution of these monomers to the physicochemical properties of the membranes (e.g., surface roughness, hydrophilicity, cross-linking density, chemical structure) as well as membranes' separation efficiency. Emergence of more favorable functional groups such as carboxylic and amine groups due to the new materials integration facilitates the polymerization process and is beneficial to the membrane properties. Here, a critical review on the new interfacial polymerization monomers applied for reverse osmosis (RO) and nanofiltration (NF) membranes fabrication is presented. The membrane molecular structure and fabrication mechanism are investigated in details. This is followed by a review of the recent surface modification methods including grafting, coating and additive incorporating into the thin layer of membranes. The application of alternative monomers to MPD, PIP and TMC are investigated and the benefits of using these monomers or co-monomers are discussed. [Display omitted] • Review of new monomers used for RO and NF membranes fabrication. • Review of alternative monomers to MPD, PIP and TMC. • Review of benefits of using new monomers as co-monomers of MPD, PIP and TMC. [ABSTRACT FROM AUTHOR]