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RSC Advances Jun 2024Because of its great efficiency and widespread application, reverse osmosis (RO) is a popular tool for water desalination and purification. However, traditional RO... (Review)
Review
Because of its great efficiency and widespread application, reverse osmosis (RO) is a popular tool for water desalination and purification. However, traditional RO membranes have a short lifespan due to membrane fouling, deterioration, decreased salt rejection rate, and the low water flux with aging. As a result, membrane modification has received a lot of attention recently, with nanomaterials being extensively researched to improve membrane efficacy and lifespan. Herein, we present an in-depth analysis of recent advances of RO membranes modification utilizing nanomaterials. An overview of the various nanomaterials used for membrane modification, including metal oxides, zeolites, and carbon nanomaterials, is provided. The synthesis techniques and methods of integrating these nanomaterials into RO membranes are also discussed. The impacts of nanomaterial change on the performance of RO membranes are addressed. The underlying mechanisms responsible for RO membrane enhancements by nanomaterials, such as improved surface hydrophilicity, reduced membrane fouling surface repulsion and anti-adhesion properties, and enhanced structural stability, are discussed. Furthermore, the review provides a critical analysis of the challenges and limitations associated with the use of nanomaterials to modify RO membranes. Overall, this review provides valuable insights into the modification of RO membranes with nanomaterials, providing a full grasp of the benefits, challenges, and future prospects of this challenging topic.
PubMed: 38873545
DOI: 10.1039/d4ra01796j -
Frontiers in Microbiology 2024DNA extraction yield from drinking water distribution systems and premise plumbing is a key metric for any downstream analysis such as 16S amplicon or metagenomics...
DNA extraction yield from drinking water distribution systems and premise plumbing is a key metric for any downstream analysis such as 16S amplicon or metagenomics sequencing. This research aimed to optimize DNA yield from low-biomass (chlorinated) reverse osmosis-produced tap water by evaluating the impact of different factors during the DNA extraction procedure. The factors examined are (1) the impact of membrane materials and their pore sizes; (2) the impact of different cell densities; and (3) an alternative method for enhancing DNA yield via incubation (no nutrient spiking). DNA from a one-liter sampling volume of RO tap water with varying bacterial cell densities was extracted with five different filter membranes (mixed ester cellulose 0.2 μm, polycarbonate 0.2 μm, polyethersulfone 0.2 and 0.1 μm, polyvinylidene fluoride 0.1 μm) for biomass filtration. Our results show that (i) smaller membrane pore size solely did not increase the DNA yield of low-biomass RO tap water; (ii) the DNA yield was proportional to the cell density and substantially dependent on the filter membrane properties (i.e., the membrane materials and their pore sizes); (iii) by using our optimized DNA extraction protocol, we found that polycarbonate filter membrane with 0.2 μm pore size markedly outperformed in terms of quantity (DNA yield) and quality (background level of 16S gene copy number) of recovered microbial DNA; and finally, (iv) for one-liter sampling volume, incubation strategy enhanced the DNA yield and enabled accurate identification of the core members (i.e., and as the most abundant indicator taxa) of the bacterial community in low-biomass RO tap water. Importantly, incorporating multiple controls is crucial to distinguish between contaminant/artefactual and true taxa in amplicon sequencing studies of low-biomass RO tap water.
PubMed: 38855767
DOI: 10.3389/fmicb.2024.1339844 -
Next Materials Jan 2024Per- and polyfluoroalkyl substances (PFAS) are oxidatively recalcitrant organic synthetic compounds. PFAS are an exceptional group of chemicals that have significant...
Per- and polyfluoroalkyl substances (PFAS) are oxidatively recalcitrant organic synthetic compounds. PFAS are an exceptional group of chemicals that have significant physical characteristics due to the presence of the most electronegative element (i.e., fluorine). PFAS persist in the environment, bioaccumulate, and have been linked to toxicological impacts. Epidemiological and toxicity studies have shown that PFAS pose environmental and health risks, requiring their complete elimination from the environment. Various separation technologies, including adsorption with activated carbon or ion exchange resin; nanofiltration; reverse osmosis; and destruction methods (e.g., sonolysis, thermally induced reduction, and photocatalytic dissociation) have been evaluated to remove PFAS from drinking water supplies. In this review, we will comprehensively summarize previous reports on the photodegradation of PFAS with a special focus on photocatalysis. Additionally, challenges associated with these approaches along with perspectives on the state-of-the-art approaches will be discussed. Finally, the photocatalytic defluorination mechanism of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) following complete mineralization will also be examined in detail.
PubMed: 38840836
DOI: 10.1016/j.nxmate.2023.100077 -
Water Environment Research : a Research... Jun 2024Ni-Mn@KL ozone catalyst was prepared for the efficient treatment of reverse osmosis membrane concentrates. The working conditions and reaction mechanism of the...
Ni-Mn@KL ozone catalyst was prepared for the efficient treatment of reverse osmosis membrane concentrates. The working conditions and reaction mechanism of the ozone-catalyzed oxidation by Ni-Mn@KL were systematically studied. Then, a comprehensive CRITIC weighting-coupling coordination evaluation model was established. Ni-Mn@KL was characterized by scanning electron microscopy, BET, X-ray diffraction, X-ray photoelectron spectroscopy, energy-dispersive spectrometry, and X-ray fluorescence spectrometry and found to have large specific surface area and homogeneous surface dispersion of striped particles. Under the optimum working conditions with an initial pH of 7.9 (raw water), a reaction height-to-diameter ratio of 10:1, an ozone-aeration intensity of 0.3 L/min, and a catalyst filling rate of 10%, the maximum COD removal rate was 60.5%. Free-radical quenching experiments showed that OH oxidation played a dominant role in the Ni-Mn@KL-catalyzed ozone-oxidation system, and the reaction system conformed to the second-order reaction kinetics law. Ni-Mn@KL catalysts were further confirmed to have good catalytic performance and mechanical performance after repeated utilization. PRACTITIONER POINTS: Ni-Mn@KL catalyst can achieve effective treatment of RO film concentrated liquid. High COD removal rate of RO membrane concentrated liquid was obtained at low cost. Ni-Mn@KL catalyst promotes ozone decomposition to produce ·OH and O · oxidized organic matter. The Ni-Mn@KL catalyst can maintain good stability after repeated use. A CRITIC weight-coupling coordination model was established to evaluate the catalytic ozonation.
Topics: Ozone; Catalysis; Osmosis; Membranes, Artificial; Water Purification; Waste Disposal, Fluid; Oxidation-Reduction
PubMed: 38831682
DOI: 10.1002/wer.11058 -
Journal of Nephrology Jun 2024The ongoing climate change and the ecological challenges call for sustainable medicine and, in our field, sustainable kidney care. Dialysis is life-saving and...
The ongoing climate change and the ecological challenges call for sustainable medicine and, in our field, sustainable kidney care. Dialysis is life-saving and resource-consuming, and high water consumption is one of the main concerns. Circular water economy, meaning reuse and recycling of water, and recovering resources can help reducing emissions and enhancing resilience to climate change. Several actions are possible including reusing reverse osmosis reject water, employable for gardening, aquaponics or even simply for toilet flushing, or in sterilization settings, reusing spent dialysate, at least for toilet flushing, but with wider use if microbiologically purified, recovering thermal energy from spent dialysate, that can probably be done with simple devices, or using phosphate-rich spent dialysate for producing fertilizers, namely struvite. All these options may be economically sound, and all help reducing the final dialysis carbon footprint. There is room for open-minded innovative approaches to improve water-related sustainability in hemodialysis, ultimately reducing ecological impact and increasing availability.
PubMed: 38831239
DOI: 10.1007/s40620-024-01989-6 -
The European Physical Journal. E, Soft... Jun 2024In this study, we demonstrate the fabrication of polymersomes, protein-blended polymersomes, and polymeric microcapsules using droplet microfluidics. Polymersomes with...
In this study, we demonstrate the fabrication of polymersomes, protein-blended polymersomes, and polymeric microcapsules using droplet microfluidics. Polymersomes with uniform, single bilayers and controlled diameters are assembled from water-in-oil-in-water double-emulsion droplets. This technique relies on adjusting the interfacial energies of the droplet to completely separate the polymer-stabilized inner core from the oil shell. Protein-blended polymersomes are prepared by dissolving protein in the inner and outer phases of polymer-stabilized droplets. Cell-sized polymeric microcapsules are assembled by size reduction in the inner core through osmosis followed by evaporation of the middle phase. All methods are developed and validated using the same glass-capillary microfluidic apparatus. This integrative approach not only demonstrates the versatility of our setup, but also holds significant promise for standardizing and customizing the production of polymer-based artificial cells.
Topics: Artificial Cells; Polymers; Emulsions; Capsules; Microfluidics; Water; Microfluidic Analytical Techniques; Proteins
PubMed: 38829453
DOI: 10.1140/epje/s10189-024-00428-5 -
Current Opinion in Cell Biology Jun 2024Nonvesicular lipid transport among different membranes or membrane domains plays crucial roles in lipid homeostasis and organelle biogenesis. However, the forces that... (Review)
Review
Nonvesicular lipid transport among different membranes or membrane domains plays crucial roles in lipid homeostasis and organelle biogenesis. However, the forces that drive such lipid transport are not well understood. We propose that lipids tend to flow towards the membrane area with a higher membrane protein density in a process termed lipid osmosis. This process lowers the membrane tension in the area, resulting in a membrane tension difference called osmotic membrane tension. We examine the thermodynamic basis and experimental evidence of lipid osmosis and osmotic membrane tension. We predict that lipid osmosis can drive bulk lipid flows between different membrane regions through lipid transfer proteins, scramblases, or similar barriers that selectively pass lipids but not membrane proteins. We also speculate on the biological functions of lipid osmosis. Finally, we explore other driving forces for lipid transfer and describe potential methods and systems to further test our theory.
Topics: Osmosis; Animals; Humans; Cell Membrane; Lipid Metabolism; Biological Transport; Lipids
PubMed: 38823338
DOI: 10.1016/j.ceb.2024.102377 -
Journal of Water and Health May 2024This study addresses the heightened global reliance on point-of-use (PoU) systems driven by water quality concerns, ageing infrastructure, and urbanization. While widely...
This study addresses the heightened global reliance on point-of-use (PoU) systems driven by water quality concerns, ageing infrastructure, and urbanization. While widely used in Egypt, there is a lack of comprehensive evaluation of these systems. We assessed 10 reverse osmosis point-of-use systems, examining physicochemical, bacteriological, and protozoological aspects of tap water (inlets) and filtered water (outlets), adhering to standard methods for the examination of water and wastewater. Results showed significant reductions in total dissolved solids across most systems, with a decrease from 210 ± 23.6 mg/L in tap water to 21 ± 2.8 mg/L in filtered water for PoU-10. Ammonia nitrogen levels in tap water decreased from 0.05 ± 0.04 to 2.28 ± 1.47 mg/L to 0.02 ± 0.04 to 0.69 ± 0.64 mg/L in filtered water. Despite this, bacterial indicators showed no significant changes, with some systems even increasing coliform levels. Protozoological analysis identified prevalent (42.5%), less frequent (2.5%), (5%), and potentially pathogenic genotypes. Elevated bacterial indicators in filtered water of point-of-use systems, combined with essential mineral removal, indicate non-compliance with water quality standards, posing a public health concern. Further research on the long-term health implications of these filtration systems is essential.
Topics: Egypt; Water Purification; Drinking Water; Osmosis; Water Quality; Water Microbiology; Filtration; Water Supply
PubMed: 38822469
DOI: 10.2166/wh.2024.036 -
Environmental Science and Pollution... Jun 2024The forward osmosis (FO) process has recently gained significant interest in treating wastewater, brackish/seawater and concentrating feedstocks for various operations,...
The forward osmosis (FO) process has recently gained significant interest in treating wastewater, brackish/seawater and concentrating feedstocks for various operations, including desalination. The study investigates the effect of different synthesis conditions of the polyamide-based thin-film composite (TFC) FO membranes on the membranes' final performance. Taguchi statistical analyses were used to fabricate and optimize the polyamide TFC FO membrane. The process parameters as factors were the amount of polyethersulfone (PES), polyethylene glycol 400 (PEG-400), polyvinyl pyrrolidone (PVP), m-phenylenediamine (MPD), and trimesoyl chloride (TMC), and TMC reaction-time (RT). The Taguchi method was adopted to investigate the optimal conditions and the significance of individual factors using an L16 (4) orthogonal array. Another Taguchi analysis (Taguchi 2) was adopted to investigate the influence of other important parameters like optimal conditions for MPD, TMC, and TMC reaction-time factors using an L9 (3) orthogonal array. Confirmation tests validated a maximum water flux of 46.4 ± 2.32 L/m·h with a specific combination of control factors for membrane synthesis: PES/PEG/PVP/MPD/TMC/TMC RT-16/7/0.5/1/0.05/30. These tests demonstrated a high-water flux of 7.05 ± 0.35 L/m·h when exposed to industrial wastewater (secondary effluent) as the feed solution (FS) and fertilizer as the draw solution (DS) in the FO process. The R values were more than 90%. The experimental validation confirmed the models' predictive ability with different FSs, including industrial wastewater.
Topics: Wastewater; Osmosis; Nylons; Membranes, Artificial; Water Purification; Waste Disposal, Fluid; Polymers
PubMed: 38822176
DOI: 10.1007/s11356-024-33742-8 -
PeerJ 2024The burgeoning issue of landfill leachate, exacerbated by urbanization, necessitates evaluating its biological impact, traditionally overshadowed by physical and...
The burgeoning issue of landfill leachate, exacerbated by urbanization, necessitates evaluating its biological impact, traditionally overshadowed by physical and chemical assessments. This study harnesses , a model organism, to elucidate the physiological toxicity of landfill leachate subjected to different treatment processes: nanofiltration reverse osmosis tail water (NFRO), membrane bioreactor (MBR), and raw leachate (RAW). Our investigation focuses on the modulation of sugar metabolism, particularly trehalose-a disaccharide serving dual functions as an energy source and an anti-adversity molecule in invertebrates. Upon exposure, showcased a 60-70% reduction in glucose and glycogen levels alongside a significant trehalose increase, highlighting an adaptive response to environmental stress by augmenting trehalose synthesis. Notably, trehalose-related genes in the NFRO group were up-regulated, contrasting with the MBR and RAW groups, where trehalose synthesis genes outpaced decomposition genes by 20-30 times. These findings suggest that predominantly counters landfill leachate-induced stress through trehalose accumulation. This research not only provides insights into the differential impact of leachate treatment methods on but also proposes a molecular framework for assessing the environmental repercussions of landfill leachate, contributing to the development of novel strategies for pollution mitigation and environmental preservation.
Topics: Animals; Caenorhabditis elegans; Trehalose; Water Pollutants, Chemical; Stress, Physiological
PubMed: 38799059
DOI: 10.7717/peerj.17332