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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]

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]

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]

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]

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]

Traditional inorganic aerogels sustainability, biodegradability, and environmental safety concerns have driven researchers to find their safe green alternatives. Recently, interest in the application of bio-aerogels has rapidly increased in the food industry due to their unique characteristics such as high specific surface area and porosity, ultralow density, tunable pore size and morphology, and superior properties (physicochemical, mechanical, and functional). Bio-aerogels, a special category of highly porous unique materials, fabricated by the sol-gel method followed by drying processes, comprising three-dimensional networks of interconnected biopolymers (e.g., polysaccharides and proteins) with numerous air-filled pores. The production of bio-aerogels begins with the formation of a homogeneously dispersed precursor solution, followed by gelation and wet gel drying procedures by employing special drying techniques including atmospheric-, freeze-, and supercritical drying. Due to their special properties, bio-aerogels have emerged as sustainable biomaterial for many industrial applications, i.e., encapsulation and controlled delivery, active packaging, heavy metals separation, water and air filtration, oleogels, and biosensors. Bio-aerogels are low-cost, biocompatible, and biodegradable sustainable material that can be used in improving the processing, storage, transportation, and bioavailability of food additives, functional ingredients, and bioactive substances for their health benefits with enhanced shelf-life. [ABSTRACT FROM AUTHOR]

Arsenate species are hazardous, toxic, and carcinogenic, they pose a significant risk to human health. In this finding, we have fabricated the Chitosan, β‐cyclodextrin and Fe2O3 (CS‐βCD‐Fe2O3) composite nanofibers through electrospinning for arsenic (As‐III) adsorption in a lab‐scale designed continuous filtration system. The SEM images have shown the bead free morphology of the prepared nanofibers and chemical composition was characterized by Fourier transforms infrared (FTIR) spectroscopy. The experimental data supported monolayer adsorptions by having a good fit to the Langmuir model. Further, kinetic studies have been conducted to illustrate the adsorption of As‐III onto CS‐βCD‐Fe2O3. The CS‐βCD‐Fe2O3 nanofibers at neutral pH have shown 83% adsorption efficiency of As‐III in the batch experiments and 72% in continuous filtration system with a flow rate of 660 mL/h. Additionally, the reusability of the nanofibers was performed, and 60% adsorption efficiency was achieved up to the 5th cycle for batch adsorption. Our prepared composite CS‐βCD‐Fe2O3 nanofibers could be used in both batch adsorption and continuous filtration system for removal of As‐III from aqueous solution. [ABSTRACT FROM AUTHOR]

Platelet-Rich Plasma (PRP) is an autologous biological product which, due to its regenerative capacity, is currently used in different fields of medicine. This biological treatment has proven to be effective in numerous research studies due to its high content of growth factors released by platelets. However, the current systems used to obtain PRP do not enrich the growth factors and cytokines outside platelets. Considering this, the present work aims to develop a new technique by which all the biomolecules present in plasma are enriched. Thus, a new method based on ultrafiltration has been developed for the obtaining of the novel PRP. By this method, ultrafiltration of the plasma water is carried out using a 3KDa filtering unit. The results showed that the technique was able to concentrate extraplatelet factors, such as IGF-1 and HGF, in contrast with conventional plasmas. Thus, the cultured cells responded with increased viability to this new PRP. These results could provide a new approach to the treatment of injuries requiring regenerative medicine, potentially improving the outcomes of the conventional PRPs. [ABSTRACT FROM AUTHOR]

Studying the quality of drinking water is one of the issues that are directly related to health and personal and public hygiene.Since water quality varies from region to region, the use of filtration techniques can produce qualitative drinking water free from organic and inorganic contaminants. The aim of this study was to investigate the physicochemical and microbial quality of water in home water filtration systems (HWFSs).In this descriptive-analytical study performed during 2019–2020, the samples were directly taken from the inlet and outlet valves of 50 HWFSs from different places of Babol city for physical, chemical, and microbial experiments. The results were analysed using SPSS 18, descriptive statistics, and t test, as well as comparing to national standards.In the current study, the concentration of Fe after passing through the HWFSs was 91.5%, the concentrations of fluoride and sulphate in the water entering the HWFSs were 75% and 69%, respectively, and the concentrations of nitrate and nitrite in water were reduced by 33% and 10%, respectively. Moreover, these HWFSs had the highest (91.5%) and lowest (10%) efficiency in the removal of Fe and nitrite. Besides, there was a significant relationship between input and output values of all parameters measured in this study (p < 0.05). No contamination of coliform was observed at the inlet and outlet of the HWFSs.The findings show the importance of regular maintenance and repair of HWFSs to ensure that water samples are in accordance with national standards. [ABSTRACT FROM AUTHOR]

Nanocellulose, an exceptional natural material acquired from cellulose, has received tremendous attention over the past decades. This is because of its unique physical characteristics, surface chemistry, functional properties, and biocompatibility. Cellulose nanocrystals (CNCs) and cellulose nanofibers (CNFs) are two major types of nanocellulose that have received key interest so far. Nanocellulose is commercially produced from wood-based sources. With the ongoing demand for nanocellulose, agricultural wastes and non-woody plants are getting much consideration as cost-efficient alternatives. Water hyacinth (WH) is an alternative source that has shown great prospects for CNC and CNF fabrication. Nanocellulose from WH is proposed for several interesting applications, such as wet-spun filaments, aerogels, packaging films, battery separators, and water filtration, showing promising results. Studies have shown the nanocellulose achieved from WH has a comparable diameter and crystallinity related to the nanocellulose derived from other agricultural wastes, but lower than nanocellulose extracted from wood. Studies were more inclined towards chemical treatments for CNC extraction and mechanical processes for CNF isolation. This review aims to emphasize identifying the true potential of WH as a nanocellulose resource by critical evaluation of the isolation processes, affecting factors on nanocellulose properties, and the foundation of future research for producing sustainable materials. It was perceived that a lot of possibilities remain unexplored as many advanced techniques are yet not well studied for WH nanocellulose extraction. Further, the advantage of being a low-lignin raw material was not properly captured by mapping the more sustainable procedures, which should be a future highlight of WH research. [ABSTRACT FROM AUTHOR]

2-Methyl-4-chlorophenoxyacetic acid (MCPA) is a highly mobile herbicide that is frequently detected in global potable water sources. One potential mitigation strategy is the sorption on biochar to limit harm to unidentified targets. However, irreversible sorption could restrict bioefficacy thereby compromising its usefulness as a vital crop herbicide. This research evaluated the effect of pyrolysis temperatures (350, 500 and 800°C) on three feedstocks; poultry manure, rice hulls and wood pellets, particularly to examine effects on the magnitude and reversibility of MCPA sorption. Sorption increased with pyrolysis temperature from 350 to 800°C. Sorption and desorption coefficients were strongly corelated with each other (R2 = 0.99; P <.05). Poultry manure and rice hulls pyrolyzed at 800°C exhibited irreversible sorption while for wood pellets at 800°C desorption was concentration dependent. At higher concentrations some desorption was observed (36% at 50 ppm) but was reduced at lower concentrations (1–3% at < 5 ppm). Desorption decreased with increasing pyrolysis temperature. Sorption data were analyzed with Langmuir, Freundlich, Dubinin–Radushkevich and Temkin isotherm models. Freundlich isotherms were better predictors of MCPA sorption (R2 ranging from 0.78 to 0.99). Poultry manure and rice hulls when pyrolyzed at higher temperatures (500 and 800°C) could be used for remediation efforts (such as spills or water filtration), due to the lack of desorption observed. On the other hand, un-pyrolyzed feedstocks or biochars created at 350°C could perform superior for direct field applications to limit indirect losses including runoff and leaching, since these materials also possess the ability to release MCPA subsequently to potentially allow herbicidal action. [ABSTRACT FROM AUTHOR]

The effect of technological parameters on the characteristics of filtering acid-resistant ceramics is investigated. A technology has been developed for producing large-sized products from ceramic electric-grade material of subgroup 110 by aqueous casting into gypsum molds. The water filtration rate was 0.02 – 0.03 ml/(cm2·h), the percentage of pores greater than 1 µm was 8 – 10%, and the average pore size was 0.04 – 0.06 µm. The variation in the pore structure of ceramic samples made of nanostructured aluminum hydroxide has been studied. The potential for their use to create ultraporous coatings is shown. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the impact of as-received biomass fly ashes (BFA) and green liquor dregs obtained from a pulp and paper plant in Brazil as substitutes for metakaolin in geopolymeric formulations. The properties of this type of waste material vary widely between different industrial plants. This study refrains from subjecting the waste materials to any form of pretreatment, taking into account their organic matter and particle size heterogeneity, requiring extensive characterization to evaluate their influence on the compressive strength, apparent open porosity, and water absorption of the geopolymeric samples. The objective was to assess their potential for upcycling purposes as an alternative to energy-intensive materials, such as ordinary Portland cement (OPC) and advanced ceramics. This potential arises from the ability of alkali-activated materials (AAM) to undergo curing at ambient temperatures, coupled with the possibility of compositions primarily derived from waste materials. To improve the sustainability of the products, the amorphous content of the raw material, which is more reactive than crystalline phases, was quantified and used as the base for mixture ratios. This approach aimed to reduce the requirement for alkaline activators, which have significant environmental impacts, while also increasing the waste content in the formulation. The incorporation of waste materials into the geopolymer matrix generally led to a reduction in the compressive strength compared to the benchmark metakaolin sample (19.4 MPa) but did not present a trend. The dregs led to values of 4.1 MPa at 25 wt% and 7.1 MPa at 50 wt%, a behavior that is somewhat counterintuitive, and BFA at 10 wt% presented 5.7 MPa. Nevertheless, the apparent open porosity remained at high levels for all the samples, close to 50%, and the compressive strength of most of them was over the values obtained for the metakaolin-only samples with mixture ratios calculated from the total composition instead of the amorphous composition. The decrease in strength and the increase in porosity were attributed to the specific characteristics of the waste materials, such as their high crystallinity, presence of organic matter, heterogeneous particle composition, and size. Overall, this study provides insight into the variations in geopolymerization based on the bulk and amorphous content of the aluminosilicate sources and how the characteristics of the waste materials influence the geopolymer matrix. It also highlights how calculating mixture ratios based on the amorphous composition improves the possibility of waste valorization through alkali activation. Additionally, it suggests that BFA and dregs might be effectively utilized in applications other than OPC substitution, such as adsorption, filtration, and catalysis. [ABSTRACT FROM AUTHOR]

The current study evaluated the use of pumice, a volcanic mineral and common sand, in treating reverse osmosis membrane reject water (ROR) using a novel combined adsorption distillation (CAD) method. The CAD method is developed to separate the dissolved solids through adsorption distillation, i.e., leaving the vaporized distillate as freshwater and concentrated brine. The adsorption potential of pumice and sand was investigated at different adsorbent doses, i.e., 2, 5, and 10 g, and consecutive CAD adsorbent backwashing cycles. The improved results were achieved at a 10 g pumice dose. However, its adsorption efficiency declined in longer CAD cycles, i.e., due to the separated deposition of solids. After backwashing, the adsorbed and accumulated salts were slightly removed, and pumice adsorption capacity was maintained for up to 20 cycles of CAD. The properties of the pumice, i.e., before and after five CAD cycles and after backwashing, were characterized with scanning electron microscopic (SEM), elemental disruptive spectroscopy (EDS), and X-ray diffraction (XRD), which revealed that the porous structure of the pumice was completely accumulated with deposits of ionic salts, which were slightly washed away after backwashing, but accumulation remained continued in post-CAD cycles. The explored method revealed a high potential of pumice in water filtration. [ABSTRACT FROM AUTHOR]

Amoxicillin (AMX) is a typical antibiotic drug detected in the aqueous environment and is potentially harmful to humans. The effects of AMX solution concentration and operating pressure on Nano filtration removal performance were investigated, and the effects of magnesium ions and humid acid (HA) on AMX separation performance were explored. The result showed that the increase of AMX concentration significantly enhanced the separation efficiency of Nano filtration, while the membrane adsorption increased; the increase of operating pressure mainly enhanced the membrane flux and had little effect on the removal rate. The addition of Mg2e caused a slight increase in the removal rate at pH 5 and 8, and a slight decrease in the removal rate at pH 10. In the presence of Hate AMX removal rate tended to decrease and then increase with increasing hand the removal rate at low HA concentration(5 mg/L) was greater than that at high concentration" 10 mg/L) . The above results showed that membrane sieving was the main mechanism of AMX removal by Nano filtration, and the addition of HA enhanced the membrane sieving erffect, and Mg2e had little eefect on the removal rate of AMX. [ABSTRACT FROM AUTHOR]

In recent works, many industrial by-products were employed as solid precursors for the synthesis of alkali-activated binders and as alternatives to Portland cement for the immobilization of hazardous, toxic and nuclear wastes. Among industrial wastes, alkali-activated brick was found to be an interesting porous composite for removing very toxic heavy metals (Pb2+, Cd2+, Co2+) and radio-nuclides (Sr2+, Cs+, Rb+) from aqueous solutions. The starting material is very attractive due to the presence of metakaolinite as a geo-polymer precursor and silica for increasing material permeability and facilitating water filtration. The alkaline reaction gave rise to geo-polymerization followed by partial zeolitization. Elemental surface micro-analysis was performed by Scanning Electron Microscopy (SEM) equipped with an Energy-Dispersive X-ray Spectrometer (EDS). The formation of crystalline phases was corroborated by X-ray diffraction (XRD) analysis. Information about 29Si, 27Al and 1H nuclei environments in crystallized and amorphous aluminosilicates was obtained by 29Si, 27Al and 1H MAS NMR. 27Al–1H dipolar-mediated correlations were investigated by employing dipolar hetero-nuclear multiple quantum coherence (D-HMQC) NMR, highlighting Al–O–H bonds in bridging hydroxyl groups (Si–OH–Al) that are at the origin of adsorptive properties. Aqueous structural stability and cationic immobilization characteristics before and after material calcination were investigated from acid-leaching experiments. [ABSTRACT FROM AUTHOR]

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Adopting standardized and reliable methodologies to accurately measure particle removal efficiency when developing fibrous materials for controlling airborne contamination is crucial. Here, we introduce well-established aerosol science and technology concepts often overlooked or misused in interdisciplinary studies developing new fibrous materials for particle filtration. We recommend best practices for experimental assessments and reporting to ensure a reliable evaluation of new airborne particle filtration media and technologies. Adopting standardized and reliable methodologies to accurately measure particle removal efficiency when developing fibrous materials for controlling airborne contamination is crucial. Here, the authors recommend best practices for experimental assessments and reporting to ensure a reliable evaluation of new airborne particle filtration media and technologies. [ABSTRACT FROM AUTHOR]

The drinking water has become contaminated with lead in many countries across the world. In this study, a novel lead-imprinted polyvinylidene fluoride (PVDF) membrane was successfully fabricated for selective decontamination of lead from water. First of all, the membrane fabrication process was explored and optimized. The physical and chemical properties were then studied for a better understanding of the features of the membrane. The performance of lead removal by the adsorptive membrane was evaluated by systematic batch adsorption experiments, including pH effect, kinetics, isotherm, selectivity, and regeneration studies. The results indicated that the adsorptive membrane showed a high adsorption capacity of 40.59 mg Pb/g at the optimal pH of 5.5, fast kinetics of 2 h, high selectivity towards lead, and outstanding regeneration performance. The Langmuir equation fitted the isotherm better than the Freundlich equation, while the pseudo-second-order model and pore diffusion model well described the kinetics. The adsorptive membrane showed high selectivity towards lead in the lead/zinc binary solution. In the continuous filtration study, a small piece of adsorptive membrane could treat 3.75 L of lead solution. The XPS studies revealed that the lead uptake was mainly due to the complex reaction between lead and carboxyl and hydroxyl in the membrane. [ABSTRACT FROM AUTHOR]

In this research work, a novel design of an electro-Fenton reactor for the treatment of polluted water was investigated. In addition to the reactor with iron electrodes, a ceramic filter was also used. An electrical circuit was designed to change the cathodes and anodes every 24 s via an electrical relay between the electrodes. The untreated water was sucked into the reactor with an air pump and entered the electrocoagulation chamber after filtration with a ceramic filter. Then, it flows to the polyethylene filter to separate the coagulated particles from the fresh water. To produce 12 L of clean water, the system consumed 100 W of energy. Analysis of a river sample showed a reduction in nephelometric turbidity units (NTUs), total suspended solids (TSS), biochemical oxygen demand (BOD), and chemical oxygen demand (COD). Turbidity reduction studies have shown that the system can improve water transparency by 95%, thereby improving water quality to acceptable levels. Further, this system reduced TSS by more than 86%. In addition, BOD was reduced by more than 84% and COD by more than 88%, as shown by the change in the ratio of BOD to COD from 0.44 to 0.625, indicating improved water quality. According to the results, the treatment system can clean polluted waters, particularly during floods and when industries discharge their effluents into rivers. [ABSTRACT FROM AUTHOR]

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.

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.

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]

Catalytic ozonation coupled with membrane filtration has been widely used in water treatment to improve effluent quality as well as control membrane fouling. In this study, the removal of natural organic matter (NOM) from surface water and the mitigation of membrane fouling by O3/H2O2/TiO2 pre-oxidation coupled with ceramic membrane in static cycling model were investigated. The results showed that the pre-oxidation of O3, O3/H2O2 and O3/TiO2 significantly improved the removal rate of NOM, with the sequence of O3/TiO2 > O3/H2O2 > O3. Under the O3/TiO2 pre-oxidation, the macromolecular substances such as aromatic proteins, fulvic acid-like and humic-like substances were completely removed, which may be due to the accelerated ozonolysis and •OH formation by TiO2. Meanwhile, three-dimensional fluorescence spectra and molecular weight distribution showed that humic acids and biopolymers were the main pollutants, and also the main causes for membrane fouling. The pre-oxidation of O3, O3/H2O2 and O3/TiO2 significantly mitigated the membrane fouling via the degradation of humic acids and biopolymers with the order of O3/TiO2 > O3/H2O2 > O3. Under the optimal pretreatment, the resistance of membrane fouling was significantly reduced, and the transmembrane pressure (TMP) decreased by 62.2%. Redundancy analysis showed that the molecular weight was the most important factor for total fouling resistance, while turbidity was negatively correlated with the fouling resistance. In addition, the O3/H2O2/TiO2 pretreatment can also enhance NOM removal and membrane fouling mitigation under long-term (48 h) cycle model. [ABSTRACT FROM AUTHOR]

Nocturia is a manifestation of systemic diseases, in which chronic kidney disease (CKD) is an independent predictor of nocturia due to its osmotic diuretic mechanism. However, to our knowledge, previous studies have not examined the association between nocturia and estimated glomerular filtration rate (eGFR). The purpose of this study was to assess the association between nocturia exposure and eGFR in the general US population. This study presents a cross-sectional analysis of the general US population enrolled in the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018. To account for potential confounding factors, linear regression analysis was conducted to investigate the association between nocturia and eGFR. Stratified analyses and interaction tests were employed to examine the variables of interest. Additionally, sensitivity analyses were conducted across diverse populations. A total of 12,265 individuals were included in the study. After controlling for confounding factors, the results of the linear regression analysis indicated that a single increase in nocturnal voiding frequency was associated with a decrease in eGFR by 2.0 mL/min/1.73 m2. In comparison to individuals with a nocturnal urinary frequency of 0, those who voided 1, 2, 3, 4, and ≥ 5 times at night experienced a decrease in eGFR by 3.1, 5.4, 6.4, 8.6 and 4.0 mL/min/1.73 m2, respectively. Nocturia was found to be associated with a decreased eGFR of 4 mL/min/1.73 m2 when compared to individuals without nocturia. The sensitivity analysis yielded consistent findings regarding the association between nocturia and eGFR in both CKD and non-CKD populations, as well as in hypertensive and non-hypertensive populations. Nevertheless, inconsistent conclusions were observed across various prognostic risk populations within the CKD context. The presence of nocturia and heightened frequency of nocturnal urination have been found to be associated with a decline in eGFR. [ABSTRACT FROM AUTHOR]

This review article focuses on the potential of biopolymer-based nanocomposites incorporating nanoparticles, graphene oxide (GO), carbon nanotubes (CNTs), and nanoclays in adsorption and membrane filtration processes for water treatment. The aim is to explore the effectiveness of these innovative materials in addressing water scarcity and contamination issues. The review highlights the exceptional adsorption capacities and improved membrane performance offered by chitosan, GO, and CNTs, which make them effective in removing heavy metals, organic pollutants, and emerging contaminants from water. It also emphasizes the high surface area and ion exchange capacity of nanoclays, enabling the removal of heavy metals, organic contaminants, and dyes. Integrating magnetic (Fe2O4) adsorbents and membrane filtration technologies is highlighted to enhance adsorption and separation efficiency. The limitations and challenges associated are also discussed. The review concludes by emphasizing the importance of collaboration with industry stakeholders in advancing biopolymer-based nanocomposites for sustainable and comprehensive water treatment solutions. [ABSTRACT FROM AUTHOR]

Reverse osmosis is efficiently used for producing drinking water from groundwater sources containing dissolved impurities, including fluoride, ammonia, lithium, strontium, boron, arsenic, etc. The principal problems of utilizing reverse osmosis include scaling on membrane surfaces, concentrate discharges, and low permeate TDS that often require conditioning. The main goal of this work was to demonstrate the viability of a newly developed methodology that relies on low-rejection nanofiltration membranes to improve product water quality by increasing its TDS and calcium content, and its economic efficiency compared to conventionally used reverse osmosis. Disadvantages of employing reverse osmosis for the production of drinking water are attributed to the fact that several pollutants (including lithium, ammonia, and boron) are monovalent ions and, as such, are poorly rejected by membranes as compared to calcium, sodium, sulfate, and chloride ions. Thus, in cases in which lithium or ammonia are present in high concentrations, high rejection membranes are usually used that result in low TDS of the product water. This article presents the results of research aimed at developing a new approach to changing the ratio of monovalent and divalent ions in product water. The new method described in this paper relies on low rejection membranes in a two-stage application that enables us to reduce monovalent impurities and increase the concentration of calcium and TDS values in product water while leaving lithium concentration unchanged. This is achieved by applying a two-stage scheme with low-rejection membranes instead of the reverse osmosis stage. The two-stage treatment using nanofiltration membranes results in the same rejection of lithium and product water quality as reverse osmosis. However, the ratio value of calcium and lithium concentrations in the concentrate of nanofiltration membranes appears to be significantly higher compared with the ratio measured in the feed groundwater. This can be attributed to different rejections of these ions by membranes. Therefore, concentration (reduction of volume) of the feed water with nanofiltration membranes and further dilution of the concentrate with deionized water produce the same concentration of lithium and are associated with an increase of 2–4 times the concentration of calcium. Treatment of this water in the second nanofiltration membrane stage produces drinking-quality water with the required lithium content and increased calcium concentration. We focus on the real-world example of groundwater treatment in Yakutia, Russia, an area where lithium concentration exceeds drinking standards by 24 times. The paper presents a technique of ion separation and demonstrates experimental results that provide lithium removal while increasing the calcium concentration and TDS value. The resulting concentrations are 2–5 times lower than those obtained via conventional use of reverse osmosis membranes. A series of experiments were conducted to remove lithium from groundwater and demonstrate the efficiency of the newly developed method of ion separation. Experimental results of the concentration of obtained values of lithium, calcium, and TDS in permeate and concentrate flows at each membrane stage demonstrate that they provide separation of monovalent and divalent ions and increase product water TDS without increasing lithium. This experimental approach increases calcium and TDS values in product water by 2–4 times compared with the use of reverse osmosis membranes. Calculations of operational costs for different options (the use of reverse osmosis, two-stage nanofiltration, and ion separation in a two-stage approach) are presented. These results confirm the economic advantage of nanofiltration membrane applications to remove lithium as compared to the use of high-rejection reverse osmosis membranes. The increase in product water TDS facilitates the further reduction of concentrate flow rate and operational costs. The economic comparison involved the calculation of the required membrane area and number of membrane elements at each stage, calcium carbonate scaling rates, reagent consumption to prevent scaling, and amounts of concentrate discharged into the sewer. Experimentally obtained results confirmed the feasibility of increasing the calcium concentration and TDS values in product water by 2–5 times while leaving the lithium concentration at the same level. Design characteristics to calculate operational costs for conventional and new options are calculated and demonstrate a sufficient (30–40%) reduction of operational costs compared to conventional use of reverse osmosis. The reduction in reagent consumption is attributed to the utilization of low-rejection nanofiltration membranes that have lower scaling propensities compared with reverse osmosis membranes and a smaller payment for concentrate discharge. The developed approach to using two-stage nanofiltration instead of single-stage reverse osmosis provides multiple advantages that include improved product water quality, lower concentrate consumption, and lower reagent consumption that are attributable to the use of low-rejection membranes. Different case studies are planned to demonstrate the efficiency of the proposed techniques to reduce ammonia, fluoride, and boron in drinking water. [ABSTRACT FROM AUTHOR]

The present study proposes a new design of mechanical filter to suit the recirculating aquaculture system (RAS) as a high-efficiency alternative filter to the conventional swirl separator (CSS). The new filter is considered the developed version of CSS; thus, it is called thereafter as the swirl-vertical drum filter (SVDF) which is provided with a rotating vertical micro-screen drum equipped with a fixed vertical brush as a self-cleaning tool instead of the conventional backwash system. The performance of SVDF was evaluated under different drum rotational speeds, and drum rotation times using sinking and floating fish feed pellets and magnetic field device, and then, it was compared to CSS in terms of water quality and filtration efficiency under the same operational conditions. Experimental results showed better values of water quality including Dissolved oxygen (DO), pH and unionized ammonia (NH3). Also, the lowest value of COD was found to be 18.33 mg/L by using SVDF with floating feed pellets, whilst the highest value of 100.73 mg/L was found in the case of using the CSS with sinking pellets. Meanwhile, the magnetic field device had no effect on the filtration process. The lowest surface area of the vertical micro-screen drum of 0.217 ± 0.013 m2 was obtained at the drum's rotational speed of 20 rpm (0.39 m/s), rotation time of 150 min with floating feed pellets. Experimentally, it is found that the new SVDF has higher filtration efficiency than the CSS by about 57.57% under the same operational conditions. [ABSTRACT FROM AUTHOR]

The river sludge in Wujin District, Changzhou City has seriously affected the surrounding environment, and the treatment and disposal of sludge has become a major problem. In this project, the combined technology of cutter suction and plate-frame pressure filtration is used to effectively treat the dredged river sludge. The combined technology specifically includes environment-friendly dredging system, pre-treatment system, conditioning and modification system, dehydration and consolidation system, and tail water treatment system. The results showed that the river sludge was separated into sludge cake and tail water from the solids/liquid mixture, wherein the sludge cake met the requirements of GB/T 23485-2009 Standard for Sludge Disposal and Mixed Landfill in Urban Sewage Treatment Plants, and the tail water met the standard of Class V water specified in GB 3838-2002 Environmental Quality Standard for Surface Water, meeting the design discharge requirements, with good social benefits. [ABSTRACT FROM AUTHOR]

Aiming at the generation of new functionalised thiosalicylate-based ionic liquids, a polymeric hydrogel consisting of 1-hexylimidazole propionitrile thiosalicylate [HIMP][TS], with a solid biomaterial support based on polyvinyl alcohol (PVA)–alginate beads, was produced. This study aimed to develop a treatment method for removing manganese (Mn) heavy metal from industrial wastewater, which is known to be toxic and harmful towards the environment and human health. The method utilised an adsorption-based approach with an alginate adsorbent that incorporated a functionalised thiosalicylate-based ionic liquid. The synthesised smooth round beads of PVA–alginate–[HIMP][TS] adsorbent were structurally characterised using Fourier transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (FESEM). The Mn concentration and removal efficiency were evaluated using atomic absorption spectroscopy (AAS). Three important parameters were evaluated: pH, adsorbent dosage, and contact time. During optimisation using the interactive factor design of experiments through the Box–Behnken model, the results showed that the system achieved a maximum Mn removal efficiency of 98.91% at an initial pH of 7.15, with a contact time of 60 min, using a bead dosage of 38.26 g/L. The beads were also tested in an available water filtration prototype system to illustrate their industrial application, and the performance showed a removal efficiency of 99.14% with 0 NTU total suspended solid (TSS) and 0.13 mg/L turbidity analysis. The recyclability of PVA–alginate–[HIMP][TS] beads using 0.5 M HCl resulted in four cycles with constant 99% Mn removal. The adsorption capacity of Mn was also determined in optimum conditions with 56 mg/g. Therefore, the alginate–thiosalicylate-based ionic liquid system is considered an effective and environmentally friendly method for removing Mn heavy metal due to the high removal efficiency achieved. [ABSTRACT FROM AUTHOR]