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A low-fouling composite cellulose membrane system, incorporating microfibrillated cellulose (MFC) and silica nanoparticle additives, was demonstrated in this study. In the membrane, a superior structural integration was observed with the inclusion of non-spherical silica nanoparticles, characterized by significantly less aggregation of the silica nanoparticles within the membrane’s scaffold, in contrast to the performance of spherical silica. Employing local wastewater, the ultrafiltration (UF) properties of the resulting composite membranes were assessed. The best-performing membrane demonstrated a superior permeation flux relative to commercial PVDF and PES membranes, maintaining a high separation efficiency (roughly 99.6%) and an excellent flux recovery ratio exceeding 90%. Examination of fouling patterns through various models revealed that the formation of a cake layer and pore constriction were probably the two primary fouling mechanisms, potentially stemming from the presence of humic substances in the wastewater. The cellulose composite membrane system’s super hydrophilic cellulose scaffold, containing silica nanoparticles, allowed for a simple hydraulic cleaning method, resulting in low fouling and high restoration capability.

Wastewater treatment plants are increasingly utilizing membrane bioreactors (MBRs), owing to the superior quality of their effluent and the minimal sludge produced. Sludge retention time (SRT), an essential parameter in MBR operation, directly impacts the microbial community’s activity and diversity. Microbial community assessments in three separate membrane bioreactors, maintained at short sludge retention times, were performed using microarrays in this investigation. The results indicated that the MBR process at a 5-day SRT (CS5) had the highest abundance of operational taxonomic units (OTUs), but this was associated with the lowest diversity and uniformity in comparison to the 3-day SRT (CS3) continuous sampling and sequencing batch (SS3). Within each of the three reactors, the Proteobacteria phylum stood out as the most abundant. The continuous model MBR results showed Bacteroidetes as the second most abundant phylum, a discrepancy from the sequencing model showing Actinobacteria’s prominence. A significant class-level difference in the Proteobacteria community was apparent between the three membrane bioreactors. Proteobacteria were the leading group in CS5 and CS3 samples, but they were also the most important group within SS3 samples. Significant overlap was observed in the composition of – , – , and -Proteobacteria across the three MBR samples. At the order level, the Proteobacteria community composition differed significantly among the three MBRs. Among the samples examined, Enterobacteriales were the most significant group in CS5 and CS3, in contrast to the dominance of Pseudomonadales within SS3. The bacterial population density, within the 5-day SRT, was, in general, more substantial than that of the other two MBR systems. A considerable disparity existed in the community composition between CS5 and both CS3 and SS3, while the phylogenetic relationships of the three MBRs displayed a degree of dissimilarity.

Extensive use of graphene in membrane technologies is justified by its distinctive optical, electrical, mechanical, thermal, chemical, and photoelectric properties, stemming from its two-dimensional hexagonal honeycomb carbon structure. The utilization of graphene membranes in water treatment studies is warranted due to their attributes of lightweight construction, mechanical strength, antimicrobial properties, and pollutant adsorption capabilities. Water treatment systems can benefit from improved photocatalysis when graphene filtering nanocomposite membranes are reinforced with nanoparticles, including carbon nanotubes (CNTs) and metal oxides. The rapid advancement of graphene nanocomposites, along with acoustically supported filtering systems incorporating graphene nanocomposite membranes and carbon nanotubes, necessitates exploration of sustainable, environmentally conscious applications. These innovative approaches are crucial for developing groundbreaking water treatment systems that effectively address current challenges. This review investigates the defining characteristics of graphene and its nanocomposites, delving into diverse synthesis and dispersion methods for graphene, carbon nanotubes, metal oxide, and polymer nanocomposites, and elaborating on membrane fabrication and characterization techniques, supported by both literature findings and our laboratory experimentation. A review of recent advancements in membrane technology, particularly in water treatment and graphene-based membranes, along with a discussion of current obstacles and future possibilities, is presented.

Water’s contribution to our well-being is undeniable and profound. In spite of this, the unavailability of fresh water and its contamination are becoming notable difficulties. The textile industry, a major polluter of water, generates high concentrations of dangerous heavy metals and hazardous dyes, posing serious health risks. A range of technologies for purifying water are available for purchase. For addressing wastewater challenges, membrane technology offers a highly advantageous and easily implemented remediation strategy. Improved functioning of the polymeric composite membranes has been accomplished by the synergistic effect of pore-forming agents, solvents, and nanoparticles. Graphene oxide (GO) was synthesized via Hummer’s method, followed by functionalization with chloroacetic acid to create c-GO. Using the phase inversion technique, different concentrations of c-GO were incorporated into thermoplastic polyurethane (TPU) membranes. For the evaluation of membrane surface morphology, chemical functionalities on membrane surfaces, and membrane crystallinity, the following techniques were sequentially employed: scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). Differential scanning calorimetry (DSC) was used to explore the temperature-dependent properties displayed by c-GO composite membranes. Water contact angle measurements were carried out to quantify the hydrophilicity of the c-GO-based TPU membrane material. The water permeability of the composite membrane demonstrated a positive correlation with the rising concentration of c-GO in the polymeric membranes. Observations suggest that C-GO could potentially enhance the physicochemical properties of the membrane. The proposed membranes are suitable and efficient candidates, applicable in multiple environmental remediation areas. Subsequently, the superior dye rejection properties of the newly designed composite membranes indicate their effectiveness in wastewater treatment.

Industrial wastewater can be effectively treated for water recovery using pressure-based membrane technologies. Research indicates that membrane pretreatment technologies, specifically microfiltration (MF), are more cost-effective than conventional pretreatment approaches and yield improved results throughout the treatment process. As a result, the MF process’s enhanced capacity to reject impurities will lead to improved efficacy in the subsequent treatment stages. This study involved the modification of 045 m cellulose acetate (CA) microfiltration membranes via vacuum filtration-assisted layer-by-layer deposition of bilayers, comprising negatively charged graphene oxide (GO) and positively charged polyethyleneimine (PEI). Within a cross-flow membrane module, the performance of 1-, 2-, and 4-bilayer GO-PEI-modified membranes was assessed concerning their dye rejection of anionic eriochrome black T (EBT) and cationic methylene blue (MB) dyes. The addition of bilayers to the membrane caused an increase in its thickness, leading to a decrease in the deionized water flux through the membranes. The flux decreased from 4877 LMH/bar for the control membrane (no bilayers) to 2890 LMH/bar for the membrane with 4 bilayers. Conversely, the performance of the modified membranes in rejecting dyes improved as more GO-PEI bilayers were layered onto the membranes. The anionic EBT dye’s rejection rate, approaching 90%, exceeded the cationic MB dye’s rejection rate of about 80%, a difference that can be attributed to the electrostatic repulsion between the negatively charged GO surface and the anionic EBT dye. BI-3231 The reclamation of 50% of the feedwater, which was imbued with saline and dye, resulted in a noted decrease of DI water fluxes of approximately 40-41% and 36%, respectively. The composite feed-water experiments exhibited a slight improvement in EBT dye rejection, attributed to the precipitation of salts on the membrane feed side or pore spaces, which in turn constricted the membrane’s pore structure.

The cellular arrangement of receptor-like kinases (RLKs) inside membrane nanodomains is a key mechanism for improving the specificity and effectiveness of plant cell signaling. Accordingly, a nanometer-scale, quantitative study of RLK spatial arrangements may provide a better understanding of plant stress response mechanisms. To ascertain the colocalization of the flagellin-sensitive-2 (FLS2) receptor and the nanodomain marker remorin, we leveraged stochastic optical reconstruction microscopy (STORM) in Arabidopsis thaliana root hair cells. Our analysis revealed that following ligand-induced internalization by bacterial-flagellin-peptide (flg22), approximately 85% of the original plasma membrane density of FLS2 and remorin was recovered after about 90 minutes. Pairs colocalized with greater frequency at the membrane compared to simulations of random pairings, excluding the immediate recovery period. This suggests that recovery starts with a lack of coordination, followed by the subsequent membrane pairing of remorin and FLS2. In terms of colocalization frequency, remorin and the purinergic receptor P2K1 were similar to FLS2; however, colocalization of FLS2 and P2K1 was observed at a significantly lower rate, suggesting that these RLKs generally occupy distinct nanodomains. FLS2 and remorin, along with CERK1, the chitin elicitor receptor, displayed colocalization at significantly reduced frequencies, implying minimal coordination between these key components. Storm’s observations highlight the existence of unique nanodomains within plant cells, along with the varying degrees of coordination among receptors and their associated immune response pathways.