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Oily wastewater poses a significant environmental concern as it has adverse effects on both ecosystems and human health. The development of highly efficient and robust antifouling membranes for oily emulsion is in great demand to prevent these serious issues in oil/water emulsion filtration. Moreover, fouling was inevitable when dealing with membrane separation. In order to overcome the addressed matters, this paper reported sprayed hydrophilic surface coating using commercialized levodopa (L -DOPA). The coated solution was mixed with 3-amino-propyltriethoxysilane in various ratios to obtain a smooth coated layer. Based on the results, the highest pure water flux and rejection efficiency of 586.51 ± 23.95 L/m2‧h and 98.22% was achieved in this study, respectively. The abundant hydroxyl and carboxyl functional groups on the membrane surface from L -DOPA benefit the membrane in many ways, especially the membrane wetting properties. The water and oil contact angles of the coated membrane increased by approximately 75% and 85%, respectively. The fouling behaviors are influenced by the presence of the coated layer, resulting in the attainment of 90% fouling resistance ratio (FRR). This is mostly due to the reduction in adherence of oil droplets on the membrane surface, hence enhancing the effectiveness of the anti-oil fouling membrane. Additionally, this provides excellent properties of the membrane to be applied in oily wastewater treatment. [Display omitted] • The MMM was coated using a solution of L -DOPA/APTES at the optimal ratio. • The presence of L -DOPA improved membrane hydrophilicity and oleophobicity. • Spray coated layer concealed rough surface of the nanocomposite membrane. • Spray coated membrane are effective in separating oil emulsions and minimizing oil fouling. [ABSTRACT FROM AUTHOR]

Recent experiments have shown that using van der Waals assembly to stack graphene layers can facilitate extraordinary transport behavior of water and ions, paving the way for the design of new desalination devices utilizing graphene channels. However, the performance of pure graphene is inadequate due to the inherent trade-off between water permeability and ion selectivity. In this study, we conducted a series of molecular dynamics simulations and found that surface functionalization can significantly enhance the desalination efficiency of multilayer graphene channels. When maintaining a constant surface charge density, the fluxes of water and ions first increase slowly and then rapidly with the increase in channel height. Notably, the channel can always achieve an ion rejection rate of over 65% for cations and more than 95% for small channel heights. Conversely, for a given channel height, an increased surface charge density causes the fluxes of water and ions to decrease rapidly to zero and the ion rejection rate to rise quickly to 100%. Additionally, the translocation time, occupancy number, and electrostatic interaction with charged residues for water and ions are heavily influenced by the channel height and surface charge density. As a result, properly sized and surface-functionalized multilayer graphene channels have the potential to revolutionize desalination membrane design, allowing for high efficiency water filtration. [ABSTRACT FROM AUTHOR]

Constructed wetlands (CWs) represent a natural wastewater treatment process, offering economic and environmental advantages. These systems can remove several components that may cause negative impacts on the environment. Media types and plant species are crucial influencing factors for the removal of contaminants in CWs. The goal of this study is to evaluate the capacity of a CW using Tamarix spp. with three filter media to treat FGD wastewater. Planted and unplanted CWs were set up with varying types of biofilm support media: 3 bioreactors were operated with 50% gravel and 50% zeolite (v/v), 3 with 100% gravel, and 3 with 50% gravel, 25% zeolite, and 25% silage. Planted CWs had the greatest potential to reduce the concentrations of B, K, and NH4+-N in 64.9%, 91.1%, and 92.5%, respectively, when used in addition to the filter composed by 50% gravel + 50% zeolite, which was the only media keeping the plants alive for 60 days. The results showed that the optimal selection of filter media depends on the purpose for which the treatment has been projected for, considering that the types of substrates influenced the nature of the contaminant removal in the CW. Salinity impact on Constructed wetlands (CWs) is still scarce in the literature. The novelty is the choice of a salt cedar (Tamarix spp.) combined with three filter media types ((1) gravel; (2) gravel and zeolite; (3) gravel, zeolite, and silage) to treat flue gas desulfurization wastewater in CWs. Our findings demonstrate that filter media containing 50% gravel + 50% zeolite can decrease the toxicity of contaminants from FGD wastewater in plants. [ABSTRACT FROM AUTHOR]

Water treatment plants play an important role in the purification and distribution of safe drinking water to the public. The present study focused on the performance assessment of the Al-Rasheed water treatment plant [ARWTP]. The main objectives of the assessment were to determine the efficiency of various plant units as well as the quality of inlet water from the Tigris River. Results obtained from the collected data indicated the presence of high concentrations of soluble nitrate and phosphate ions in the filtered water. The removal efficiency of alkalinity, EC, total hardness, SO4, Cl, NO3 and PO4 were found to be (+11.05%), (-0.67%), (-29.33%), (-2.64%), (-6.25%), (-32.13%), and (0%) respectively. The removal efficiency was negative for some parameters which means that the concentration before treatment was less than the concentration after treatment. Water treatment facilities in Al-Rasheed water treatment plant need modernization and rehabilitation. Using pre-chlorination as an effective method for the controlling algal growth in the conventional water treatment plants is highly recommended. [ABSTRACT FROM AUTHOR]

The objective of this research is to characterize the hydrological network of the "Hondo" estuary micro-basin through the use of morphometric and biophysical parameters, in order to analyze and predict its hydrodynamic behavior, in order to contribute to environmental management plans and be a contribution to the conservation and protection of optimal conditions for their development. Three shape parameters, two of relief, its drainage network and physiography were analyzed. While in the biophysical variables they were calculated by means of ArcGIS geospatial information processing, identifying their temperature, precipitation, soil texture, land use and cover, slope and taxonomy. According to the results obtained, its morphometry the micro-basin presented an oblong or rectangular shape, a moderate drainage network, where it is concluded that its water system is not prone to present flood peaks, due to the stability of its runoff regimes. superficial. However, as it is a young basin and presents a concave hypsometric shape, it is likely that it will experience high erosive processes in the future. Finally, in the biophysical component it was identified that the texture of the soil was mostly sandy loam, with strong and steep slopes and a predominance of alfisols whose water filtration is low, where it is concluded that the micro-basin could present loss of the layer vegetative by dragging sediment. [ABSTRACT FROM AUTHOR]

In Pakistan, just 25% of the population has sustained access to high-quality drinking water, which is below tolerable limits. The study area under consideration was DHA Phase II, Islamabad, Pakistan. The research conducted aiming the valuable insights for the water quality testing using different parameters and piper analysis to relate the water quality. The purpose of the study was to examine the efficiency of the filtration plants in the sector by performing different tests on water samples. A total of 22 samples were tested for physicochemical contamination, heavy metals, and microbiological contamination. The investigation examined water samples at various stages, before, during, and after filtration. Samples were collected in water bottles as assigned by EPA that underwent washing with distilled water, rinsing, sealing, and subsequent transportation to the EPA lab. The samples underwent analysis utilizing Atomic Absorption and UV Spectrophotometry. The results underscore the necessity of the enhanced water quality standards as high concentration of lead, nickel, cadmium and chromium was detected along with high concentration of total hardness, sulfates and chlorides in various plants, which is quite alarming. In conclusion to our findings, it is strongly advised that authorities take proactive measures to supervise and maintain filtration plants to prevent contamination and enhance overall performance. [ABSTRACT FROM AUTHOR]

The Clostridium perfringens bacteria are used to assess water quality as an indicator parameter. If detected, it can confirm the occurrence of past fecal contamination. Tests determining C. perfringens in water samples are usually performed by membrane filtration where filters are incubated on selective media under anaerobic conditions. Available media include mCP and TSC. The aim of this study was to compare the relative recovery of C. perfringens (including spores) from surface water samples and to determine the performance characteristics of the membrane filtration method using both media. The results showed that, although the procedure using the mCP medium was more sensitive and specific, higher recoveries were obtained in the tests based on the TSC medium. [ABSTRACT FROM AUTHOR]

A study of the filter properties of soils in relation to water and air in the manor park in Kozłówka in the Lublin Province was carried out. The natural soils of the area are represented mainly by black soils formed from loamy sand. The soils of the park show significant differences from the natural soil cover, as they have been subjected to radical anthropogenic impacts as a result of various works associated with the construction and redevelopment of the palace buildings and the change of land use. As a result, there are now soils within the park that are classified as Anthrosols or Technosols. In all the studied pedons, the natural genetic horizons were obliterated, in some layers there was a change in the texture. The positive effect of anthropogenisation was mainly manifested in the high organic carbon content of the surface layer of all pedons. To analyse the filter properties of the soils, samples of preserved structure were taken from layers 0-10 cm, 20-30 cm and 40-50 cm into standard cylinders. The following properties were determined: the water filtration coefficient in the saturated zone (Ks); the water permeability; the air permeability at water potential states in the range -0.98 kPa to -49.00 kPa; the full water capacity and the air capacity. Considering the area of the entire park, it must be said that the filtration properties showed high levels in relation to both water and air. The water permeability was characterised by very high values. Also for air permeability in the field water capacity condition, very high and high values predominated. Particularly high values of this trait were found in the surface layer, rich in organic carbon. The presence of construction debris in large quantities in Urbic Technosols had the effect of reducing air permeability. The results obtained from the study of the filtering properties of the soils of the manor park in Kozłówka can provide an essential source of information which is the basis for undertaking possible recultivation and care works, which are necessary for the conscious shaping of the park establishment. [ABSTRACT FROM AUTHOR]

The application of membrane technology in wastewater treatment for reuse is one of the alternatives to reduce the demand of water in domestic, agricultural and industrial sectors. This study attempts to improve wastewater quality effluent, prior to disinfection, for re-use. Clarifier effluent from a biological nutrient removal (BNR) treatment plant was diverted to a nonwoven membrane pilot filtration unit. It was thus positioned to further enhance the clarifier effluent as a polishing arrangement. Water Quality Index (WQI), Single Factor Pollution Index (Pi), Water Use License (WUL) and removal efficiency methods were used to interpret the water quality data for BNR clarifier effluent and nonwoven membrane permeate. The results showed that this nonwoven microfilter membrane is able to improve wastewater quality from BNR clarifier effluent. Escherichia coli (E. coli) reduction was the highest with a removal efficiency of 90%, followed by chemical oxygen demand 25%, NH4+ 22%, NO3− 12.6%, PO4 7.8%, suspended solids 6.3%. The lowest reduction was electrical conductivity of 5.2%. Permeate results indicated that physiochemical and microbial parameters were complying with the limits of WUL. Pi has revealed that BNR clarifier effluent water quality is medium polluted versus slightly polluted permeate. WQI results for BNR clarifier effluent showed good water quality and the water can be reused for domestic, irrigation and industrial purposes, while permeate WQI results indicated excellent water quality and the water can be reused for drinking, domestic, irrigation and industrial purposes. Outstanding permeate water quality improvement was observed on E.coli counts improving from 4974.48 to 294.33 counts/L. The standard of E.coli according to the WUL at this wastewater care works is 500 counts/L. Results indicate that nonwoven membrane filtration can improve microbial contamination and decrease the demand of chlorine for disinfection of wastewater final effluent. The nonwoven membrane filtration can decrease the water scarcity gap in South Africa for direct water reclamation by improving effluent wastewater. [ABSTRACT FROM AUTHOR]

Immunofluorescence staining is used to investigate proteins and protein interactions in oocytes. In typical protocols, the medium that suspends the oocytes requires replacement more than ten times during the staining procedure; this is time-consuming, technically challenging and not amenable to automation. We developed a filtration method using negative pressure to replace manual replacement of medium. We investigated oocyte loss, time required and staining results using our filtration method compared to traditional procedure. We found that our filtration method reduced oocyte loss by at least 60% and decreased the time required to obtain comparable staining outcomes. It provides an efficient and fast way to replace culture medium for oocytes. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) distinguish themselves from conventional materials by their exceptional combination of characteristics, including a well‐defined crystalline structure, inherent porosity, substantial surface area, remarkable design flexibility, capacity for functionalization, and chemical tunability. These attributes collectively contribute to the distinctiveness and versatility of COFs compared to traditional materials. This opens up exciting possibilities for multiple applications including energy storage, sensing, gas extraction and catalysis. The extraordinary stability of COFs in aqueous solutions and under harsh climatic conditions opens up new applications for them, including water treatment. COFs are attractive materials for tackling water pollution concerns and expanding their applications in related fields as a result of their distinctive attributes, like remarkable adsorption ability and adjustable architectures. The use of COF membranes in effluent management can improve the elimination of harmful dyes, resulting in better water quality and environmental protection. The creation of COF‐based membranes is a significant step forward in the field of water filtration and shows great potential for solving the issues faced by industrial wastewater contamination. Many published techniques provide continuous COF‐based membranes that fully utilize COFs for separations. Performance and characterization of COF‐membranes can be arbitrated with the help of various analytical and spectroscopic methods. The present study marks the most important structural characteristics and functional design methodologies of COFs in the form of thin membranes for dye separation. A discussion on the characteristics of COFs responsible for membrane separation with their synthesis and characterizations has also been done. Various reported fabrication methods of COF based membranes for dye removal are discussed concisely. [ABSTRACT FROM AUTHOR]

Water filtration is an important application to ensure the accessibility of clean drinking water. As requirements and contaminants vary on a local level, adjustable filter devices and their evaluation with contaminants are required. Within this work, modular filter devices are designed featuring an adjustable surface functionalization. For this purpose, 3D‐printed structures are created consisting of bio‐based poly(lactic acid) (PLA) that are manufactured by extrusion printing. The surface of PLA is activated with amino groups that are used to install xanthates as chain transfer agents. Subsequently, photo‐iniferter (PI) polymerization is used to create cationic polymer brushes on the surface of PLA substrates. Multiple surface characterization techniques are employed to prove successful growth of polymer brushes on PLA. After initial optimization studies on flat surfaces, filter devices are printed, functionalized, and used to remove bacteria from contaminated water. Significant reduction of the number of microorganisms is detected after filtration (single filtration or cycling) and contaminating organism can also be removed from freshwater samples by simple incubation with a 3D‐printed filter. The herein developed setup for producing functional filter devices and probing their performance in affinity filtration is a useful platform technology, enabling the rapid testing of polymer brushes for such applications. [ABSTRACT FROM AUTHOR]

Polymeric membranes are useful tools for water filtration processes, with their performance strongly dependent on the presence of hydrophilic dopants. In this study, polyaniline (PANI)-capped aluminosilicate (halloysite) nanotubes (HNTs) are dispersed into polyether sulfone (PES), with concentrations ranging from 0.5 to 1.5 wt%, to modify the properties of the PES membrane. Both undoped and HNT-doped PES membranes are investigated in terms of wettability (static and time-dependent contact angle), permeance, mechanical resistance, and morphology (using scanning electron microscopy (SEM)). The higher water permeance observed for the PES membranes incorporating PANI-capped HNTs is, finally, assessed and discussed vis-à-vis the real distribution of HNTs. Indeed, the imaging and characterization in terms of composition, spatial arrangement, and counting of HNTs embedded within the polymeric matrix are demonstrated using non-destructive Micro Particle Induced X-ray Emission (µ-PIXE) and Scanning Transmission Ion Microscopy (STIM) techniques. This approach not only exhibits the unique ability to detect/highlight the distribution of HNTs incorporated throughout the whole thickness of polymer membranes and provide volumetric morphological information consistent with SEM imaging, but also overcomes the limits of the most common analytical techniques exploiting electron probes. These aspects are comprehensively discussed in terms of practical analysis advantages. [ABSTRACT FROM AUTHOR]

Drinking water contamination by per- and polyfluorinated alkyl substances (PFAS) is a global concern. Nanofiltration is a promising PFAS removal technology due to its scalability and cost-effectiveness. However, nanofiltration cannot typically reduce PFAS concentrations below current drinking water recommendations. To enhance PFAS removal, we developed mixed-matrix-composite nanofiltration (MMCNF) membranes—an active nanofiltration layer on porous adsorptive support that synergetically combines filtration and adsorption. We synthesized MMCNF membranes comprising thin polyelectrolyte multilayer films deposited on thick (~400 µm) polyethersulfone supports incorporating β-cyclodextrin microparticles. These membranes achieved near complete removal (>99.9%) of model PFAS (PFOA: perfluorooctanoic acid) for significantly longer filtration times compared to a control membrane without β-cyclodextrin, but otherwise identical. The spent MMCNF membrane was regenerated using ethanol, and high PFOA removal performance was regained during three filtration cycles. Perfluorooctanoic acid was concentrated 38-fold in the ethanol eluent. Further concentration by evaporation is straightforward and can enable eluent recycling and effective PFAS removal. [ABSTRACT FROM AUTHOR]

Identifying processes that confer resilience against global change is a scientific challenge but is central to managing ecosystem functionality in future. Detecting resilience-enhancing mechanisms is especially relevant in coastal ecosystems, where multi-stressor interactions can drive degradation over time. Here, we quantify the resilience-conferring potential of endobenthic sandprawns against eutrophication, including under high temperatures. We show using a global change mesocosm experiment that sandprawn presence was associated with declines in phytoplankton biomass, particularly under eutrophic conditions, where sandprawns reduced phytoplankton biomass by approximately 74% and prevented a shift to extreme eutrophy. Eutrophic waters were nanophytoplankton-dominated, but sandprawn presence countered this, resulting in even contributions of pico- and nanophytoplankton. Our findings highlight the potential for sandprawns to increase resilience against eutrophication by limiting phytoplankton blooms, preventing extreme eutrophy and counteracting nanophytoplankton dominance. Incorporating endobenthic crustaceans into resilience-based management practices can assist in arresting future water quality declines in coastal ecosystems. [ABSTRACT FROM AUTHOR]

This paper demonstrates that air‐stable radicals enhance the stability of triboelectric charge on surfaces. While charge on surfaces is often undesirable (e.g., static discharge), improved charge retention can benefit specific applications such as air filtration. Here, it is shown that self‐assembled monolayers (SAMs) containing air‐stable radicals, 2,2,6,6‐tetramethylpiperidin‐1‐yl)oxidanyl (TEMPO), hold the charge longer than those without TEMPO. Charging and retention are monitored by Kelvin Probe Force Microscopy (KPFM) as a function of time. Without the radicals on the surface, charge retention increases with the water contact angle (hydrophobicity), consistent with the understanding that surface water molecules can accelerate charge dissipation. Yet, the most prolonged charge retention is observed in surfaces treated with TEMPO, which are more hydrophilic than untreated control surfaces. The charge retention decreases with reducing radical density by etching the TEMPO‐silane with tetrabutylammonium fluoride (TBAF) or scavenging the radicals with ascorbic acid. These results suggest a pathway toward increasing the lifetime of triboelectric charges, which may enhance air filtration, improve tribocharging for patterning charges on surfaces, or boost triboelectric energy harvesting. [ABSTRACT FROM AUTHOR]

Wastewater irrigation may reintroduce fecal pathogens to households and cause drinking water contamination. The aim of this study was to assess the effect of wastewater irrigation on the quality of drinking water among wastewater-irrigating urban farming households. Drinking water samples from 52 households of farming communities in 19 sampling sites were collected twice at PoS and PoC. The microbial quality of the water was assessed using E. coli counted by membrane filtration. Samples collected from exposed households at PoC were 100% positive for E. coli with mean E. coli at PoC increased 10× from the PoS and 3× higher compared to PoC in the unexposed households. The absence of hand washing water (ATE = 8.14), water storing (ATE = 7.75) and intermittent water supply (ATE = 6.25) were significant factors for the increased E. coli at PoC. Breaking the path of the pathogens from the farm to the house and from PoS to PoC needsintervention. [ABSTRACT FROM AUTHOR]

The spatial and spectral information brought by the Very High Resolution (VHR) and multispectral satellite images present an advantage for Satellite-Derived Bathymetry (SDB), especially in shallow-water environments with dense wave patterns. This work focuses on Tavşan Island, located in the Sea of Marmara (SoM), and aims to evaluate the accuracy and reliability of two machine learning (ML) regression methods, Multi-Layer Perceptron (MLP) and Random Forest (RF), for bathymetry mapping using Worldview-2 (WV-2) imagery. In situ bathymetry measurements were collected to enhance model training and validation. Pre-processing techniques, including water pixel extraction, sun-glint correction, and median filtering, were applied for image enhancement. The MLP and RF regression models were then trained using a comprehensive dataset that included spectral bands from the satellite image and corresponding ground truth depth values. The accuracy of the models was assessed using metrics such as Root-Mean-Square Error (RMSE), Mean Absolute Error (MAE), and R2 value. The RF regression model outperformed the MLP model, with a maximum R2 value of 0.85, lowest MAE values from 0.65 to 1.86 m, and RMSE values from 0.93 to 2.41 m at depth intervals between 6 and 9 m. These findings highlight the effectiveness of ML regression methods, specifically the RF model, for SDB based on remotely sensed images in wave-dense shallow-water environments. [ABSTRACT FROM AUTHOR]

Oil spill accidents have been a prevalent threat to the environment. To aid in clean-up efforts, a stainless-steel filter with a hydrophilic and oleophobic coating was fabricated for efficient and affordable oil/water separation. Two solutions were used to deposit the coatings. One was sourced from a titanium (IV) isopropoxide (TTIP) precursor dissolved into 1-butanol and the other through the mixing of titanium dioxide nanopowder with glacial acetic acid. The solutions were applied to 304 stainless-steel mesh filters of varying aperture sizes ranging from 30 microns to 240 microns. The coating was applied through a multiphase deposition method followed by sintering at 450 °C. The filter performance was evaluated by contact angle measurement and a filtration test using a mixture of motor oil and water, while the surface morphology and structure of the coatings were characterized by SEM-EDS and XRD. The mesh with smaller aperture size showed oil retention improvement of up to 99%. The TiO2 nanopowder coating, with a 92% oil retention efficiency, outperformed the coating via the TTIP precursor. [ABSTRACT FROM AUTHOR]

Insufficient permeability and membrane fouling significantly influence the efficiency of ceramic microfiltration (MF) membranes in oil/water emulsion treatment. In this study, a high-flux whisker layer ceramic MF membrane with super-hydrophilicity was successfully fabricated through gel-spin coating method and a low-temperature oxidation method, which was used to separate oil/water emulsion. The effects of the whisker layer and surface wettability were systematically investigated, and the mechanism of in-situ gelling and pore size distribution was proposed. The super-hydrophilic ceramic MF membrane with an average pore size of 250 nm exhibited a high gas flux of 934 m3/(m2·h·bar) and excellent pure water flux of 9754 L/(m2 h bar). Even after a long-term circulating filtration process, the super-hydrophilic ceramic MF membrane still maintained a high water flux of over 50 L/(m2·h) at a transmembrane pressure of 5 KPa during the treatment of oil-in-water emulsion with a concentration of 1000 mg/L. Overall, the developed ceramic MF membrane demonstrated high permeability and excellent anti-fouling performance, making it a promising candidate for oil/water emulsion wastewater treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

This study focuses on investigating and comparing the influence of the surface functional groups and chemical matrices of macroporous resin on the Cr(III) exchange mechanism. The results discussed herein indicate that sulfonic resin removed Cr(III) ions with faster kinetics than carboxylic resin. Equilibrium was established within 15 and 7 min for the carboxylic and sulfonic resins, respectively, with a 99.5% removal efficiency at 333 K. The Langmuir exchange capacity was observed to be higher for the sulfonic resin (1.5 mmol∙g−1) than the carboxylic resin (0.80 mmol∙g−1) at 333 K. The adsorption isotherms obtained for the carboxylic and sulfonic resins were H and S types, respectively, representing a higher affinity of the carboxylic resin for Cr(III) removal at a low metal ion concentration. Additionally, it was noted that the carboxylic resin preferentially co-sorbed H+ and Cr(OH)2+ ions below Cr(III) concentrations of 6–8 mmol.L−1. The H+ ions co-sorption was almost negligible, whereas the Cr(III) exchange was 87 and 34.5% for the carboxylic acid resin and sulfonic acid resins, respectively. The data of the concentration studies were evaluated using non-linear forms of Freundlich, Langmuir, and Dubinin–Radushkevich adsorption isotherm models, and the kinetic data were analyzed using pseudo-Ist- and pseudo-IIst-order kinetic models. The activation energy Ea for Amberlite IRC-50 (Na+) was greater (22.4 kJ∙mol−1) than that of Amberlyst-15 (Na+) 17 kJ∙mol−1, indicating a higher energy barrier for the ion exchange reaction on carboxylic resin. As per the findings of a statistical error analysis (RMSE and SSE) and absolute average relative distribution (AARD) statistical model, a close agreement between the experimental and theoretical values suggested that the Langmuir isotherm was well-fitted to the current adsorptive investigations. The interaction of the COO− and SO3− functional sites of the resins for the exchange of Cr(III) ions was validated through an FT-IR analysis. The macroporous resins used in the current study for Cr(III) exchange showed promising performances compared to other resins. The current investigations revealed valuable insights for choosing macroporous resins as adsorbents in water filtration systems. [ABSTRACT FROM AUTHOR]

Existing polyamide (PA) membrane synthesis protocols are underpinned by controlling diffusion-dominant liquid-phase reactions that yield subpar spatial architectures and ionization behavior. We report an ice-confined interfacial polymerization strategy to enable the effective kinetic control of the interfacial reaction and thermodynamic manipulation of the hexagonal polytype (Ih) ice phase containing monomers to rationally synthesize a three-dimensional quasilayered PA membrane for nanofiltration. Experiments and molecular simulations confirmed the underlying membrane formation mechanism. Our ice-confined PA nanofiltration membrane features high-density ionized structure and exceptional transport channels, realizing superior water permeance and excellent ion selectivity. [ABSTRACT FROM AUTHOR]

Positive biodiversity–ecosystem functioning (BEF) relationships observed in experiments can be challenging to identify in natural communities. Freshwater animal communities are disproportionately harmed by global change that results in accelerated species loss. Understanding how animal‐mediated ecosystems functions may change as a result of global change can help determine whether biodiversity or species‐specific conservation will be effective at maintaining function. Unionid mussels represent half of imperiled species in freshwater ecosystems globally and perform important ecological functions such as water filtration and nutrient recycling. We explored BEF relationships for 22 naturally assembled mussel aggregations spanning three river basins. We used the Price equation to partition the contributions of species richness, composition, and context dependent interactions to two functions of interests: spatially‐explicit standing‐stock biomass (indirect proxy for function) and species‐specific nitrogen (N) excretion rates (direct measure of N recycling). Random and non‐random species loss each reduced biomass and N recycling. Many rare species with low contributions to biomass contributed to standing‐stock biomass in all basins. Widespread species had variable function across sites, such that context dependent effects (CDEs) outweighed richness effects on standing‐stock biomass in two basins, and were similar to richness effects in the third. Richness effects outweighed CDEs for N recycling. Thus, many species contributed a low proportion to overall N‐recycling; a product we attribute to the high evenness and functional effect trait diversity associated with these communities. The loss of low‐functioning species reduced the function of persisting species. This novel result using observational data adds evidence that positive species interactions, such as interspecific facilitation, may be a mechanism by which biodiversity enhances ecosystem functions. Our work stresses the importance of evaluating species‐specific contributions to functions in diverse systems, such as nutrient cycling when maintaining specific animal‐mediated functions is a management goal because indirect proxies may not completely characterize BEF relationships. [ABSTRACT FROM AUTHOR]

Water availability is an important issue all over the world, and membrane filtration technology is one of the most effective measures for remediation. As a sustainable and renewable biomass material, natural wood has a hierarchical and three-dimensional interconnected microstructure, which provides an alternative for water filter design. Longitudinal filtration could take advantage of the micropores, while the treatment speed is severely limited. This study examined a wood filter in which muddy wastewater can be transported into the microchannels and out of the vertically stacked micropores. The filter takes full advantage of the pores present in the wood without sacrificing the speed of hydraulic flow within the main transport channels, exhibiting excellent performance for mud removal. In this manner, water flux, decolorization, and turbidity are highly dependent on the groove number, groove depth, and thickness of the filter. Due to the reorientation of the water transport pathways, the clogging of micropores could be easily alleviated, thus promoting the filter lifecycle. The design of the cross-flow wood filter can provide an available platform for various wastewater treatment cases with different impurities, displaying an application prospect in the wastewater treatment field. [ABSTRACT FROM AUTHOR]

A common problem in laboratory-scale membrane research is that the testing methods in the laboratory are often quite different than industrial applications due to the limitations of manual experimental setups. Here, an automated membrane filtration apparatus was built in the lab to solve this problem by allowing long-term filtration, frequent backwash and clean-in-place (CIP), and high-accuracy operation. The filtration system achieves different cleaning strategies for both theoretical research and practical water and wastewater scale-up experiments. The embedded control algorithms achieve operational accuracy in terms of maintaining flux or transmembrane pressure (TMP) at their desired set points. A flux-step function enables operators to measure critical flux automatically. The filtration system handles a variety of microfiltration and ultrafiltration membranes in crossflow or dead-end mode with backwash integration, CIP capability, and aeration scouring. Synthetic and raw rendering wastewater were applied to test the apparatus in the lab and in the field, respectively. The control algorithms successfully dampened oscillations using custom calibration curves. Three backwash-CIP strategies were tested with both wastewater types. The first was time-triggered backwash and cycle number–triggered CIP, which resulted in stable and reliable operation but required close operator control and thus was not fully automated. The second strategy was time-triggered backwash with TMP-triggered CIP, which responded quickly to water quality fluctuations and achieved full automation, but the TMP target had to be carefully set to enhance the efficiency of CIP. The third strategy was target–TMP backwash with duration-triggered CIP, which can achieve the most advanced and flexible filtration system, though setting up this level of automation complexity in the field was challenging. Both backwash and CIP frequencies responded to real-time performance automatically. Ultimately, the automated lab-scale filtration apparatus operated similarly to full-scale systems, which should help fill the gap between laboratory research and scale-up of industrial applications. Laboratory membrane filtration research is usually different than industrial applications because lab workers are limited in their ability to perform all the steps that are done at full scale. An automated filtration system can solve the problem by performing continuous monitoring and control without user intervention. This paper provides detailed information about building and operating an automated filtration apparatus. The apparatus can perform experiments in the lab or the field where water quality fluctuates. All the important steps are included automatically: filtration, backwash, and CIP. This article discusses how to adjust the timing and the triggering of each step for optimal performance. Other functions, like an algorithm to easily determine critical flux, are also described. This should allow other researchers to build similar systems, thus making more laboratory work directly relevant to full-scale applications. [ABSTRACT FROM AUTHOR]

Cryomilling is a promising method for fabricating polymeric blend and composite powder raw materials for various subsequent manufacturing processes. In this study, biodegradable porous membranes were fabricated from poly (ε-caprolactone) (PCL) using the cryomilling/hot pressing/porogen leaching approach. Powder mixtures of six different model compositions were compounded by cryomilling; thereafter, films were fabricated by hot-pressing. Poly (ethylene-oxide) (PEO) and salt were utilized as eco-friendly porogens in these mixtures, which were dissolved in water to introduce porosity in the films. Wood sawdust (WSD) and alum were investigated as fillers potentially capable of manipulating the hydrophilicity, mechanical and antimicrobial properties of the membranes. The morphological, hydrophilicity, mechanical, and filtration efficiency properties were explored and compared to those of commercial laboratory microfiltration (MF) membranes. SEM analysis revealed dense membrane skins for all compositions, along with lamellar porous structures. Mean pore radius ranged from 0.15 to 0.21 μm, which is within the MF pore size range. Water contact angle measurements averaged 70° and decreased with the addition of WSD and alum, indicating increased hydrophilicity. Tensile test results showed a decrease in mechanical properties, with higher porosities and with the addition of WSD. Adding alum (≥10 wt%) resulted in embrittled membranes. Filtration performance was evaluated in terms of pure water flux and turbidity reduction for textile wastewater, and it compared favorably to commercial membranes. In conclusion, this study has successfully introduced a new facile and versatile membrane fabrication approach. [ABSTRACT FROM AUTHOR]

The role of bivalve molluscs in the biological treatment of polluted natural waters is considered. The anatomical structure and tissue composition of these hydrobionts enabling the effective filtration and purification of water from suspended pollutants are given. It is shown that molluscs simultaneously create a biogenic water circulation that mixes water masses. Water absorption and circulation within the mantle cavity provides bivalve molluscs with oxygen and food necessary for respiration, which has a substantial effect on the biogenic migration of chemical elements in aquatic ecosystems. These circumstances make it possible to design special bioreactors that can be used, together with other hydrobionts, such as algae and bacteria, for biological treatment of natural reservoirs polluted by sewage. A plan has been drawn up to conduct experiments to study the rate of filtration and purification of contaminated water by bivalve mollusks. In this regard, the use of a bioreactor with bivalve molluscs in drinking water purification systems at the first stage of water treatment is worthy of attention. [ABSTRACT FROM AUTHOR]

The effect of 3D printed modified Chitosan membranes on bacterial strains by water filtration system was explored in this study. Specifically, it focused on the characterisation of 3D printed Chitosan–graphene oxide–silver nanoparticles (CS–GO–AgNP) composite membranes and the effects of Dimethylacetamide (DMAc) used as co-solvent on the performance of the CS–GO–AgNP nanocomposites. It also examined the impact of GO–AgNP on the CS matrix for inhibition of Fecal Coliforms, Total Coliforms and Escherichia coli (E. coli) bacterial strains in contaminated surface water. The increase in DMAc concentration and subsequent reduction in CS mole fraction within the ink formulation resulted to wider distribution of AgNP across membrane surface, improvement in mechanical strength and surface hydrophilicity of the modified CS membranes. Similarly, increase in GO–AgNP concentration effectively reduced the spread of the identified microorganisms. Sample B-12 with 79% CS, 21% DMAc and 1.2 ml of GO–AgNP exhibited the highest inhibition of the bacterial strains, with more than 95% of Fecal and Total Coliforms suppressed or inactivated, while 99.9% of the E. coli bacterial cells were completely prevented, indicating that our 3D printed modified CS membranes can effectively be used for water treatment. [ABSTRACT FROM AUTHOR]

Ceramic membranes have become one of the most rapidly developing and promising membrane materials owing to their excellent properties. Compared with other membrane materials, ceramic membranes are widely used in the wastewater and water treatment fields owing to their advantages, including higher chemical stability, stronger mechanical strength, longer service life, and better water filtration performance. In this paper, the sources of raw materials and their preparation for the production of ceramic membranes are briefly introduced. The methods for preparing ceramic membranes are described in detail, including the role of ceramic membranes in water treatment applications, the preparation methods of the membranes, and the latest progress in this area, along with a review of the applications of ceramic membranes in wastewater and water treatment. Simultaneously, this study also evaluates which preparation method is the most advantageous and the aspects of its advantages. The raw materials used in the ceramic membrane preparation and the types of water treatment suitable for this method were studied. The results showed that the phase-conversion sintering technique has multiple advantages, and the generated asymmetric structure with finger- and sponge-like voids can further improve the flux and separation abilities, which are attractive for scientific researchers. Finally, the development trends in the inorganic ceramic membrane market were surveyed. This work can help beginners understand the preparation procedures employed to produce ceramic membranes for water treatment; compare the porosity, mechanical strength, permeation flux, and chemical and thermal stability of the resulting membranes; and reasonably select the appropriate preparation method for the relevant water treatment type. [ABSTRACT FROM AUTHOR]

Over the past few years, the environment and public safety have suffered due to the detrimental effects of oily industrial effluents. Natural fibers have gained popularity for their affordability, reusability, and effectiveness in separating oil from oily wastewater. Milkweed fibers were characterized using FTIR (Fourier transform infrared spectroscopy), SEM (scanning electron microscopy), and contact angle techniques. With four porosities (0.90, 0.92, 0.95, and 0.98), deep bed coalescence filters were built at three different filter bed heights (10 mm, 20 mm, and 30 mm). Using milkweed coalescence filtering technology, a novel oil separation method is described along with a method to calculate oil film thickness following emulsified oily water saturation. By combining a bed height of 30 mm and a porosity of 0.98, a maximum oil separation of 99.73% and an optimized D50 droplet ratio were achieved. Throughout a prolonged operational period lasting 250 min, the filter bed, possessing a depth of 30 mm and a porosity of 98%, exhibited no discernible fouling indications. Following five cycles, the milkweed filter bed measuring 30 mm in depth and featuring a porosity of 98% displayed an impressive oil separation efficiency of 91.5%. This study found that using a milkweed deep bed filter, coalescence filtering effectively removes oil from oily effluent. Furthermore, milkweed is a natural and biodegradable fiber that is easy to dispose of after use and does not harm the environment. [ABSTRACT FROM AUTHOR]

This research used the hand impress moulding method to prepare ceramic filter pots using 500 μm sieved clay, grog, and melon shell in three ratios of 70:5:25, 75:5:20, and 80:5:15, respectively. The pot models were dimensioned to 50 mm height, 52 mm outer diameter, and 10 mm thickness and fired to 650°C, 700°C, and 750°C. The volume of effluent, flow rate, and microbial removal efficiency were studied. From the results, filter pot 70:5:25 fired to 750°C recorded an efficiency of 99.9% removal of heterogenic bacteria count, total fungi count, total coliform, and E.coli, and has the best combination of flow rate and removal efficiency. This filter pot was seen to meet up with the World Health Organization (WHO) standards. Minitab analyses show a significant effect of material composition over fired temperature on the flow rate.

The article discusses the importance of coagulation in surface water treatment plants and the challenges associated with optimizing this process. Coagulation plays a crucial role in achieving water quality goals and operational efficiency, but there have been limited advancements in recent years. The article explores the need for rethinking treatment approaches and the potential of new technologies, such as artificial neural networks, to improve coagulation processes. However, there are challenges related to data collection and diversity, and it will require investment and collaboration to develop models that comprehensively understand the coagulation process. [Extracted from the article]

The article discusses the historical use of lead-containing pipes in North America's water infrastructure and the detrimental effects of lead ingestion. It highlights the importance of evaluating lead in drinking water components and the role of the U.S. Environmental Protection Agency (EPA) and the NSF/ANSI/CAN 372 standard in creating guidelines to protect the public from lead. The article explains that NSF/ANSI/CAN 372 certification ensures that drinking water filtration systems meet the EPA's lead requirements and provides third-party verification for manufacturers. It also outlines the process of certification and the ongoing auditing and retesting required to maintain compliance. The article emphasizes the importance of monitoring lead levels in drinking water and the need for transparent certifications like NSF/ANSI/CAN 372 to ensure the safety of clean drinking water. [Extracted from the article]

This article discusses the issue of lead in drinking water and the importance of home water filtration systems. It acknowledges that despite efforts to reduce lead levels, there are still millions of lead pipes in homes across the United States. New regulations are being implemented to further reduce lead levels, but they may temporarily increase lead in home drinking water. The article emphasizes the need for in-home, point-of-use water filtration systems to ensure safe drinking water. It also highlights the challenges of partial replacement of lead service lines and the responsibility of homeowners to replace the private side of the home water service line. The article concludes by discussing the role of home water filtration systems in providing a permanent solution and peace of mind for homeowners. Additionally, the given text provides a buyer's guide for water purification products and companies, listing various companies and organizations specializing in water filtration and purification systems. This resource could be helpful for library patrons researching water purification options. [Extracted from the article]

Polytetrafluoroethylene (PTFE) capillary membranes, known for the great chemical resistance and thermal stability, are commonly used in membrane separation technologies. However, the strong hydrophobic property of PTFE limits its application in water filtration. This study introduces a method whereby acrylamide (AM), N, N-methylene bisacrylamide (MBA), and vinyltriethoxysilane (VTES) undergo free radical copolymerization, followed by the hydrolysis-condensation of silane bonds, resulting in the formation of hydrophilic three-dimensional networks physically intertwined with the PTFE capillary membranes. The modified PTFE capillary membranes prepared through this method exhibit excellent hydrophilic properties, whose water contact angles are decreased by 24.3–61.2%, and increasing pure water flux from 0 to 1732.7–2666.0 L/m2·h. The enhancement in hydrophilicity of the modified PTFE capillary membranes is attributed to the introduction of hydrophilic groups such as amide bonds and siloxane bonds, along with an increase in surface roughness. Moreover, the modified PTFE capillary membranes exhibit chemical resistance, maintaining the hydrophilicity even after immersion in strong acidic (3 wt% HCl), alkaline (3 wt% NaOH), and oxidative (3 wt% NaClO) solutions for 2 weeks. In conclusion, this promising method yields modified PTFE capillary membranes with great hydrophilicity and chemical resistance, presenting substantial potential for applications in the field of water filtration.

ABSTRACT: Introduction. The aim of the work is to determine the influence of the structure of the filter materials formed as a result of modification of the surface layer on their water permeability and the size of trapped solid particles. Materials and methods. The non-woven fabrics from a mixture of polyethylene-terephthalate (PET) (70 wt.%) and bicomponent fibers (BCF) of the coreshell structure were used as objects of the study. The non-woven fabrics were obtained by mechanically forming the canvas with its subsequent hardening by needle punching. The resulting materials were modified by heat treatment. The water transfer in the modified materials was determined by the permeability coefficient. The filtration efficiency was determined by the number of trapped particles of a certain size. Results and discussion. The needle-punched non-woven fabrics without additional heat treatment are not suitable for water filtration. The proposed method of thermal and deformation-thermal modification provides the production of gradient materials with a controlled thickness of the nanoscale surface layer. Although a decrease in water permeability is observed, the modified material traps solid particles with a smaller (compared to unmodified ~ 20 µm) equivalent diameter of 2–4 µm, which is sufficient to prepare water for use in steam generators and in the production of building materials. Conclusion. The optimal parameters of deformation-heat treatment for obtaining the high-effective filtration non-woven materials were established: the temperature – 180оC, the processing speed – 3.5 m/min.