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To oxidize trace concentrations of organic contaminants under conditions relevant to surface- and groundwater, air-diffusion cathodes were coupled to stainless-steel cathodes that convert atmospheric O2 into hydrogen peroxide (H2O2), which then was activated to produce hydroxyl radicals (·OH). By separating H2O2 generation from its activation and employing a flow-through electrode consisting of stainless-steel fibers, the two processes could be operated efficiently in a manner that overcame mass-transfer limitations for O2, H2O2, and trace organic contaminants. The flexibility resulting from separate control of the two processes made it possible to avoid both the accumulation of excess H2O2 and the energy losses that take place after H2O2 has been depleted. The decrease in treatment efficacy occurring in the presence of natural organic matter was substantially lower than that typically observed in homogeneous advanced oxidation processes. Experiments conducted with ionized and neutral compounds indicated that electrostatic repulsion prevented negatively charged ·OH scavengers from interfering with the oxidation of neutral contaminants. Energy consumption by the dual-cathode system was lower than values reported for other technologies intended for small-scale drinking water treatment systems. The coordinated operation of these two cathodes has the potential to provide a practical, inexpensive way for point-of-use drinking water treatment.

Dichloramine (NHCl2) naturally exists in reverse osmosis (RO) permeate due to its application as an antifouling chemical in membrane-based potable reuse treatment. This study investigated mechanisms of background NHCl2 hydrolysis associated with the generation of oxidative radical species in RO permeate, established a kinetic model to predict the oxidative capacity, and examined its removal efficiency on trace organic contaminants in potable reuse. Results showed that NHCl2 hydrolysis generated transient peroxynitrite (ONOO-) and subsequently dissociated into hydroxyl radical (HO•). The maximal HO• exposure was observed at an RO permeate pH of 8.4, higher than that from typical ultraviolet (UV)-based advanced oxidation processes. The HO• exposure during NHCl2 hydrolysis also peaked at a NH2Cl-to-NHCl2 molar ratio of 1:1. The oxidative capacity rapidly degraded 1,4-dioxane, carbamazepine, atenolol, and sulfamethoxazole in RO permeate. Furthermore, background elevated carbonate in fresh RO permeate can convert HO• to carbonate radical (CO3•-). Aeration of the RO permeate removed total carbonate, significantly increased HO• exposure, and enhanced the degradation kinetics of trace organic contaminants. The kinetic model of NHCl2 hydrolysis predicted well the degradation of contaminants in RO permeate. This study provides new mechanistic insights into NHCl2 hydrolysis that contributes to the oxidative degradation of trace organic contaminants in potable reuse systems.

UNLABELLED: Wastewater treatment plants (WWTPs) are indispensable biotechnology facilities for modern cities and play an essential role in modern urban infrastructure by employing microorganisms to remove pollutants in wastewater, thus protecting public health and the environment. This study conducted a 13-month bacterial community survey of six full-scale WWTPs in Hong Kong with samples of influent, activated sludge (AS), and effluent to explore their synchronism and asynchronism of bacterial community. Besides, we compared AS results of six Hong Kong WWTPs with data from 1,186 AS amplicon data in 269 global WWTPs and a 9-year metagenomic sequencing survey of a Hong Kong WWTP. Our results showed the compositions of bacterial communities varied and the bacterial community structure of AS had obvious differences across Hong Kong WWTPs. The co-occurrence analysis identified 40 pairs of relationships that existed among Hong Kong WWTPs to show solid associations between two species and stochastic processes took large proportions for the bacterial community assembly of six WWTPs. The abundance and distribution of the functional bacteria in worldwide and Hong Kong WWTPs were examined and compared, and we found that ammonia-oxidizing bacteria had more diversity than nitrite-oxidizing bacteria. Besides, Hong Kong WWTPs could make great contributions to the genome mining of microbial dark matter in the global wanted list. Operational parameters had important effects on OTUs abundance, such as the temperature to the genera of Tetrasphaera, Gordonia and Nitrospira. All these results obtained from this study can deepen our understanding of the microbial ecology in WWTPs and provide foundations for further studies. IMPORTANCE: Wastewater treatment plants (WWTPs) are an indispensable component of modern cities, as they can remove pollutants in wastewater to prevent anthropogenic activities. Activated sludge (AS) is a fundamental wastewater treatment process and it harbors a highly complex microbial community that forms the main components and contains functional groups. Unveiling who is there is a long-term goal of the research on AS microbiology. High-throughput sequencing provides insights into the inventory diversity of microbial communities to an unprecedented level of detail. At present, the analysis of communities in WWTPs usually comes from a specific WWTP and lacks comparisons and verification among different WWTPs. The wide-scale and long-term sampling project and research in this study could help us evaluate the AS community more accurately to find the similarities and different results for different WWTPs in Hong Kong and other regions of the world.

Prussian blue analogue (PBA) membranes for efficient Cs removal via in situ synthesis have attracted much interest. Herein, copper-substituted PBA was developed and optimized on the surface of a substrate with the aid of tannic acid (TA). The fabricated Cu-PBA-TA membrane was systematically investigated for its Cs adsorption property in static and dynamic experiments. The as-prepared membrane showed a maximum adsorption capacity of 265.0 mg g−1, which was the highest when compared to that of previously reported PBA membranes. Applied in geothermal water, the Cu-PBA-TA membrane showed favorable selectivity (Kd, 8680 mL g−1) and the removal rate of Cs+ was about 90%. Its fast adsorption rate that reached equilibrium within 40 min and the benign reusability in the dynamic treatment of geothermal water confirmed the potential of the membrane for large-scale application. [ABSTRACT FROM AUTHOR]

We successfully fabricated Ag@Cu2O core–shell decorated on reduced graphene oxide (rGO) nanocomposites (ACRN) with a simple and convenient in situ substitution method. The properties of these ACRNs with heterostructure layers were characterized by scanning and transmission electron microscopy and absorption spectroscopy. We used 4-nitrophenol (4-NP) as a probe molecule to determine the chemical catalytic activity of the ACRN. Upon introduction of rGO, a high electron transfer efficiency was achieved; thus, the catalytic activity was improved significantly. Therefore, the ACRN exhibited significantly improved catalytic activity for the reduction of 4-NP and showed high application value in the removal of toxic and harmful substances from water. The catalytic efficiency was improved by 1.7 times by using the ACRN compared to Ag–rGO. In addition, the fabricated ACRN was used for the reduction of an organic dye (methyl orange, MO), and explosive pollutant (trinitrophenol, TNP) to generate nontoxic products. Furthermore, the high charge redistribution and transfer among Ag, Cu2O, and rGO in the ACRN induced the high catalytic reduction of organic pollutants, indicating the excellent potential of these materials for applications in water pollution treatment. [ABSTRACT FROM AUTHOR]

One of the most effective ways to reduce environmental pollution on the earth's surface is the catalytic decomposition method. In this paper, the co-precipitation method was successfully used to synthesize pure and Sm (3, 5, and 7 wt%) doped WO 3 nanoparticles by various weight percentage. The structural and optical properties of prepared NPs were characterized using XRD, SEM, EDS, HR-TEM, XPS, FTIR and UV–Vis. From XRD analysis confirmed the monoclinic phase of WO 3 as well as the substitutional incorporation of Sm in WO 3 lattice. The surface morphology of the obtained samples was studied by SEM and HR-TEM, which shows nanoplate morphology. EDS and XPS analysis element confirmation for W, O and Sm. The systematic decrease of bandgap (E g) from 2.86 to 2.82 eV with increasing Sm doping concentration from 0 to 7 wt% was strong evidenced from UV–Vis analysis. Furthermore, the extensive surface area of the active CV curves and EIS indicating the good to improve photocatalytic performance and photo-generated carriers' separation efficiency. The photodegradation of Methyl Blue (MB) aqueous solution in 120 min under the visible light irradiation is used to assess the photocatalytic activity of the prepared samples. Among the four samples, 7 wt% doped one shows higher degradation efficiency of 94.2 %. Finally, the antibacterial properties of Sm:WO 3 (0, 3, 5 and 7 wt%) NPs against Staphylococcus aureus (MTCC 8708) were investigated with the disc diffusion method and zone of inhibition in mm were recorded. Based on the above analysis, the superior antibacterial activity against Staphylococcus aureus (18 mm) is rather obtained with Sm:WO 3 (7 wt%) sample. [ABSTRACT FROM AUTHOR]

This investigation is motivated by the surge of interest in materials, combining high spontaneous magnetization and pseudocapacitance at room temperature. Ferrimagnetic MnFe 2 O 4 offers benefits of high magnetization. However, the non-pseudocapacitive behavior, low capacitance and high resistance of MnFe 2 O 4 are limiting factors for its applications in magnetic pseudocapacitive devices. This investigation demonstrates that nearly ideal pseudocapacitive behavior can be achieved for MnFe 2 O 4 electrodes in Na 2 SO 4 electrolyte. High pseudocapacitance is observed in positive and negative potential ranges and two different charging mechanisms are proposed. High capacitance is achieved at a low impedance. The ability to achieve comparable and high areal capacitances in the positive and negative potential ranges facilitates the fabrication of a symmetric pseudocapacitive device, containing ferrimagnetic MnFe 2 O 4 as cathode and anode material for operation in enlarged voltage window of 1.6 V. The symmetric device shows capacitance of 0.92 F cm−2 at a current density of 3 mA cm−2. The individual electrodes and device show good cycling stability. The approach is based on the use of murexide and gallocyanine as redox-active dispersants and charge transfer mediators. The analysis of testing results provides an insight into the influence of chemical structure, charge and redox properties of the dispersants on the capacitive behavior. The ability to fabricate a pseudocapacitive device, containing two ferrimagnetic electrodes is promising for energy storage, water purification and novel applications based on magnetocapacitive effects. [ABSTRACT FROM AUTHOR]

Research efforts are focusing on investigating cost-effective and ecologically friendly ways to create nanoparticles as a result of promising developments in green technology (NPs). This experiment focused on the effectiveness of using biochar (TWB) made from coffee waste to extract levofloxacin (LEV) from water. The conclusive results of the trials showed that TWB is an effective adsorbent for removing LEV from liquid solutions. The TWB produced through biological processes underwent comprehensive analysis using techniques such as X-ray diffractometry (XRD), scanning electron microscopy (SEM), Brunauer–Emmett–Teller surface area measurement (BET), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) spectroscopy. The bioengineered TWB's exceptional crystalline properties, which closely resemble the monoclinic structure of bulk TWB, were confirmed by the XRD analysis. Based on the scanning electron microscopy (SEM) data, the synthesis of TWB Nanoparticles resulted in the formation of spherical particles with an approximate diameter of 40 nm, accompanied by a substantial surface area of 285.55 m²/g. The Pseudo-Second-Order model, which best captured Levofloxacin's adsorption characteristics, was evaluated on the TWB, and the results showed that external mass transfer was the main determinant of response rate. It was also found that the adsorption process was endothermic and spontaneous. The system was optimized using the Box–Behnken design (BBD) methodology. The achieved removal capacity of 1119.19 mg/g utilizing the tested adsorbent was determined to be reasonable when compared to the performance of other previously used adsorbents when evaluating the effectiveness of eliminating LEV. The process of LEV adsorption onto TWB involves a number of different mechanisms, such as ion exchange, π-π interactions, electrostatic pore filling, and hydrogen bonding. Following extensive testing in connection with a real-world sample, the adsorbent demonstrated remarkable efficacy, and it maintained good performance even after undergoing three further regeneration cycles. By adjusting the annealing temperature, we controlled the synthesis of TWB nanoparticles across a range of sizes in order to maximize their antibacterial capabilities. This research utilized a pair of Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) and a pair of Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli) to evaluate the antibacterial efficacy of TWB. Highlights: Green synthesis of biochar via using tea waste. Adsorption studies of harmful pesticides Levofloxacin (LEV). The adsorbents exhibited good reusability for four adsorption/desorption cycles. Adsorption fit with pseudo second order kinetics and Langmuir isotherm model. The adsorption fitted to pseudo-second-order kinetically. This system will provide helpful guidance for coloured effluent treatment. Optimized the results by using Box-Behnken design. [ABSTRACT FROM AUTHOR]

Ultrafiltration (UF) membranes with excellent dye removal and antibacterial activity are highly desired in dye wastewater treatment, and more importantly environmental protection puts high demands on polymeric membrane materials. In this work, three methacrylate copolymers containing quaternary ammonium salt were synthesized to cast UF membranes. The physicochemical property, structural evolution, dye separation, and antibacterial activity of as‐prepared membranes were systematically investigated. With increased content of the hydrophilic monomer allyl polypropylene glycol (APPG) in the feed, the wettability and positive charge of the resultant membranes were enhanced. Remarkably, the supporting layer of membranes changed from finger‐like pore structure to sponge‐like pore structure by increasing APPG content, and the sponge‐like membranes showed higher retention rates for dyes (99.78% for victoria blue B, 90.49% for methylene blue, and 97.43% for methyl blue) compared with the finger‐like membranes. Besides, the sponge‐like membranes exhibited high rejection for vctoria blue B (>99%) in dye/salt mixture and simultaneously low rejection for salts (<10%), indicating effective selective separation to dye/salt mixture, and also achieved easy regeneration. It was also found that increased hydrophilicity and positive charge endowed membranes with better antibacterial activity. This work will provide an alternative for dye/salt selective separation in dye effluent treatment. [ABSTRACT FROM AUTHOR]

Porous hydrogels have been developed to be highly efficient interfacial solar vapor generation materials for obtaining affordable freshwater supplies. However, realizing hydrogel materials with portability, adequate water supply, and durable mechanical properties remains challenging. Herein, a scalable and portable hydrogel with 3D‐shaped recovery, highly efficient water transport, and robust mechanical stability is reported, which is prepared by foaming polyvinyl alcohol (PVA) and modification of phosphotungstic acid (PTA). Due to the interconnected porous structure and highly permeable polymer network, the PVA/PTA‐PH hydrogel has good repetitive compressibility and rapid shape recovery when in contact with water. Combined with light‐absorbing nanoparticles, the PVA/PTA‐PH hydrogel presents an impressive solar evaporation rate of 3.876 kg m−2 h−1 and a photothermal conversion efficiency of ≈94% under 1‐sun irradiation. With 3D‐shape recovery and highly efficient water transport, the compressed hydrogel can be quickly unfolded without human intervention and restored to five times the original size for the working state. The good portability, excellent seawater desalination performance, and simple preparation process are anticipated to make the PVA‐/PTA‐PH hydrogel a promising material to continuously and conveniently produce pure water from seawater. [ABSTRACT FROM AUTHOR]

This current investigation explored the thermal conversion process of castor wood into biochar, which was subsequently harnessed for removing naproxen from pharmaceutical industrial effluent via adsorption. Surface composition analyses conducted through scanning electron microscopy–energy dispersive X‐ray, laser‐induced breakdown spectroscopy, and Fourier‐transform infrared studies unveiled the presence of nano MgO particles within the adsorbent material. Employing optimization techniques such as response surface methodology facilitated a refined approach to batch study. The optimized conditions for batch naproxen sodium (NPX) adsorption on nano‐MgO‐modified biochar were identified as pH 4, 1.5 g/L adsorbent dosage, and a 120‐min contact time maintaining a constant NPX concentration of 10 mg/L. The adsorption capacity was calculated to be 123.34 mg/g for a nano‐magnesium oxide‐modified castor wood biochar (modified biochar) and 99.874 mg/g for pristine castor wood biochar (pristine biochar). Fenton's reagents comprising 15 mM of FeSO4 (7H2O) and 25 mM of H2O2 have been scrutinized under conditions of pH 3.0, a reaction time of 30 min, a temperature of 30°C, and stirring at 120 rpm, followed by batch adsorption treatment. The COD, NH3–N, NO3−, PO43−, and NPX removal percentages was found to be 90%, 87%, 79%, 80%, and 90%, respectively. Thus nano MgO‐modified biochar holds promise of treatment of pharmaceutical effluent. [ABSTRACT FROM AUTHOR]

• Alum sludge is a low-cost alternative Si and Al source for zeolite synthesis. • Recycle alum sludge for zeolite synthesis reduce water treatment's environmental impact. • Zeolite synthesis from alum sludge provides a sustainable way to waste management. • Aluminosilicate synthesis using alum sludge adds an economic/environmental value. Alum sludge (AS) is a by-product generated from drinking water treatment and produced in large amounts around the world. Its chemical composition makes this waste an emerging alternative source of silicon and aluminum for aluminosilicates or zeolite material production, which can add value to residues and contribute to the circular economy process on a global scale. In this sense, and considering the scarcity of information about AS, this review shows data collection about AS in different countries, including generation, chemical composition, and disposal information. The reuse of AS is discussed based on circular economy and the environmental gains derived from such approaches are highlighted, including the possibility of utilization with other residues (e.g., ash, bioproducts, etc). Moreover, this review shows and discusses the benefits and challenges of AS reuse in the synthesis process and how it can be a sustainable raw material for aluminosilicates and zeolite synthesis. The most common conditions (conventional or non-conventional) in zeolite synthesis from AS are mentioned and advantages, limitations and trends are discussed. The discussions and data presented can improve the AS management and reuse legislations, which certainly will collaborate with sustainable AS use and circular economy processes. [ABSTRACT FROM AUTHOR]

The extensive application of neonicotinoid insecticides (NNIs) has resulted in its worldwide detection in waters, leading to risks to human health and ecology safety. Presently, various remediation techniques for NNIs have been developed. However, the critical reviews concerning the remediation approaches for the elimination of NNIs from water are limited. Considering tremendous efforts have been made in the research topic of NNIs removal recently, this study systematacially reviewed the current advances on NNIs remediation approaches, including adsorption, Fenton, ozonation, photodegradation, sulfate radicals based-advanced oxidation processes (AOPs), electrochemical AOPs, percarbonate-based AOPs, periodate-based AOPs, microbial remediation, and phytoremediation. Moreover, NNIs removal by these methods have been critically discussed, compared, and analyzed. Furthermore, mechanisms of different treatment processes have been summarized in detail. Finally, the challenges and perspectives have been proposed. This study highlights the current progresses on NNIs removal technologies and proposes the future research needs in this area, which will provide support to further researches to halt the NNIs contamination. [ABSTRACT FROM AUTHOR]

A novel type of oxide material, high entropy oxide (Mn0.2Fe0.2Co0.2Ni0.2Cu0.2)3O4 (MFO) composites with spinel structure were successfully synthesized by a simple solution combustion in this paper, and it was first applied to the degradation of antibiotic organic pollutants in water by photo-Fenton. SEM and BET characterization showed that the composite was porous and had a large specific surface area. XPS results showed that Fe, Mn, Cu, Co and Ni all participated in the redox reaction of the catalytic process. The redox pairs of Mn2+/Mn3+, Cu+/Cu2+, Co2+/Co3+, Ni2+/Ni3+ can accelerate the Fe2+/Fe3+ redox cycling in MFO to activate H2O2 and produce more reactive oxygen species. The catalytic performance of MFO composite was investigated using tetracycline hydrochloride (TC-HCl) as a model pollutant. The results displayed that the degradation rate of TC-HCl by MFO was 92.9% when the initial pH was 4, the dose of H2O2 was 50 mM, and the irradiation time was 60 min. The high entropy oxide MFO composites could build up an internal electric field, which restrains electron–hole recombination, improves the transfer of photogenerated charge carriers and maximize photocatalytic property. In addition, the free radical capture experiment determined that the main active species of the degradation reaction were e−, •O2− and •OH. The synergistic effect of the five components in the high entropy oxide strengthens lattice distortion and defects, increases oxygen vacancies, and thus has enhanced catalytic effect for TC-HCl degradation. This work shows that high entropy oxides have excellent catalytic performance for tetracycline organic pollutants, and it is speculated that high entropy oxides have good application prospects in the field of advanced oxidation technology for the degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

Nitrospira is a common genus of nitrite-oxidising bacteria (NOB) found in wastewater treatment plants (WWTPs). To identify the key factors influencing the composition of NOB communities, research was conducted using both sequencing batch reactor (SBR) and continuous flow reactor under different conditions. High-throughput 16S rRNA gene sequencing revealed that Nitrospira (18.79% in R1 and 25.77% in R3) was the dominant NOB under low dissolved oxygen (DO) and low nitrite (${\rm NO}_2^-$ NO 2 − -N) concentrations, while Nitrobacter (21.26% in R2) was the dominant NOB under high DO and high ${\rm NO}_2^-$ NO 2 − -N concentrations. Flocculent and granule sludge were cultivated with Nitrospira as the dominant genus. Compared to Nitrospira flocculent sludge, Nitrospira granule sludge had higher inhibition threshold concentrations for free ammonia (FA) and free nitrous acid (FNA). It was more likely to resist adverse environmental disturbances. Furthermore, the effects of environmental factors such as temperature, pH, and DO on the activity of Nitrospira granular sludge were also studied. The results showed that the optimum temperature and pH for Nitrospira granular sludge were 36°C and 7.0, respectively. Additionally, Nitrospira granular sludge showed a higher dissolved oxygen half-saturation constant (Ko) of 3.67 ± 0.71 mg/L due to its morphological characteristics. However, the majority of WWTPs conditions do not meet the conditions for the Nitrospira granular sludge. Thus, it can be speculated that future development of aerobic partial nitrification granular sludge may automatically eliminate the influence of Nitrospira. This study provides a theoretical basis for a deeper understanding of Nitrospira and the development of future water treatment processes. [ABSTRACT FROM AUTHOR]

P-bromophenol (4-BP) is a toxic halogenated phenolic organic compound. The conventional treatment processes for 4-BP elimination are costly and inefficient, with complete mineralization remaining a challenge for water treatment. To overcome these limitations, we investigated the treatment of 4-BP in a membrane biofilm reactor (MBfR) using hydrogen as an electron donor. The pathway of 4-BP degradation within the H2-MBfR was investigated through long-term operational experiments by considering the effect of nitrate and 4-BP concentrations, hydrogen partial pressure, static experiments, and microbial community diversity, which was studied using 16S rRNA. The results showed that H2-MBfR could quickly remove approximately 100% of 4-BP (up to 20 mg/L), with minimal intermediate product accumulation and 10 mg/L of nitrate continuously reduced. The microbial community structure showed that the presence of H2 created an anaerobic environment, and Thauera was the dominant functional genus involved in the degradation of 4-BP. The genes encoding related enzymes were further enhanced. This study provides an economically viable and environmentally friendly bioremediation technique for water bodies that contain 4-BP and nitrates. [ABSTRACT FROM AUTHOR]

The agricultural growth of the nation resulted in the elevated amount of agricultural toxic contaminants in water. It is a promising technique for the degradation of agricultural pollutants. Photocatalysis is termed the utilization of light energy as an inexhaustible and green energy source for degrading organic pollutants through reactive oxygen species generation. The agricultural pollutants mainly comprise pesticides, herbicides, and certain veterinary contaminants. This paper aims to discuss the prevalence of various photocatalytic agents in the degradation process of agricultural pollutants in water. Considering this, the present review has attempted to look back at the existing research based on applying chemical agents as photocatalysts to treat contaminated water systems. Literature that falls within the period from 2018 to 2023 is chosen, and the effects of various photocatalytic agents on agricultural pollutants have been explored. The categorization of the existing literature is highly relevant for future research that aims to recognize the role of photocatalytic agents and their contribution toward the purification of water systems and the eradication of agricultural pollutants. It also highlights the challenges and benefits of incorporating photocatalytic agents for the degradation process of agricultural pollutants. [ABSTRACT FROM AUTHOR]

In this paper, we present the synthesis and characterisation of an anthraquinone-based discotic liquid crystal (DLC), AFLC-14-doped ceric phosphate, a novel composite ion exchanger which exhibits superior ion exchange properties. The incorporation of AFLC-14 betwixt the layers of ceric phosphate aims to strengthen the material’s thermal property, adsorption capacity, and disinfectant properties along with ion-exchange capabilities. The reported material underwent extensive physico-chemical characterisation using various analytical techniques, including FTIR, UV-vis spectrophotometry, XRD analysis, SEM imaging, TGA/DTA studies and elemental investigation. Additionally, ion-exchange characteristics were investigated, encompassing ion-exchange capacity, concentration dependency, thermal property, adsorption studies for alkaline earth and heavy/transition metal ions, and binary separation experiments. Our findings reveal that the incorporation of a DLC betwixt ceric phosphate matrix significantly improves the exchanger’s overall performance. Notably, the hybrid ion exchanger exhibits remarkable selectivity for mercury (II) ions, indicating its potential for selective ion removal applications in environmental remediation and water purification processes. [ABSTRACT FROM AUTHOR]

Background: Antiviral drugs show significant efficacy in non-severe COVID-19 cases, yet there remains a subset of moderate COVID-19 patients whose pneumonia continues to progress post a complete course of treatment. Plasma-activated water (PAW) possesses anti-SARS-CoV-2 properties. To explore the potential of PAW in improving pneumonia in COVID-19 patients following antiviral treatment failure, we conducted this study. Methods: This was a randomized, controlled trial. Moderate COVID-19 patients with antiviral treatment failure were randomly assigned to the experimental group or the control group. They inhaled nebulized PAW or saline respectively. This was done twice daily for four consecutive days. We assessed improvement in chest CT on day 5, the rate of symptom resolution within 10 days, and safety. Results: A total of 23 participants were included, with 11 receiving PAW and 12 receiving saline. The baseline characteristics of both groups were comparable. The experimental group showed a higher improvement rate in chest CT on day 5 (81.8% vs. 33.3%, p = 0.036). The cumulative disappearance rate of cough within 10 days was higher in the experimental group. Within 28 days, 4 patients in each group progressed to severe illness, and no patients died. No adverse reactions were reported from inhaling nebulized PAW. Conclusion: This pilot trial preliminarily confirmed that nebulized inhalation of PAW can alleviate pneumonia in moderate COVID-19 patients with antiviral treatment failure, with no adverse reactions observed. This still needs to be verified by large-scale studies. Trial registration: Chinese Clinical Trial Registry; No.: ChiCTR2300078706 (retrospectively registered, 12/15/2023); URL: www.chictr.org.cn. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTCommercial microalgae production is often interrupted by contamination, leading to short production cycles, reinoculation needs, and culture collapses, significantly increasing costs. This study focuses on investigating Recirculated Sedimentation Application (RSA) to control contamination in microalgae culture systems used for wastewater treatment. Chlorella vulgaris culture was grown in an unsterilized mixture of tertiary treatment effluent and centrate of anaerobic digestion wastewater sludge over a 90-day experimental period. 60 L raceway reactor was operated under a light intensity of 275 μM m−2.s−1 with a 16:8 h light-dark photoperiod. To evaluate the effect of RSA on biological-based problems, the experiment was conducted in three phases. The benefits of utilizing RSA were established through the following observations: effective removal of contaminants at an acceptable level without releasing the culture; extension of the biofilm formation time on the inner walls; inhibition of heterotrophic bacteria and nitrification; enhancement of the suspended solids retention capacity of the raceway tank (up to 770 mg.L−1); and improvement in ammonium removal rate to approximately 30 mg.L−1d−1. The ideal salinity level for both ammonium removal and biomass concentration in RSA should be below 0.02%. These findings demonstrate the potential of phycoremediation for sustainable wastewater treatment and contribute to environmental bioremediation strategies.This study investigates the effects of recirculated sedimentation using freshly formed and mature algae, based on settleability differences, for microalgae cultivation in open ponds with unsterilized wastewater, with the aim of maintain a stable and productive biomass community. Additionally, this study contributes to expand the current knowledge on several fronts: including removing contaminants without discharging the culture, improving biomass holding capacity of the reactor, reducing biofilm formation on reactor walls, suppressing bacterial growth in the culture media and enhancing ammonium removal rate. To the best of our knowledge, there have not been no previous studies to evaluate the effectiveness of sedimentation for these purposes. [ABSTRACT FROM AUTHOR]

MgO nanoparticles have good As-adsorption capacity in treating As-contaminated wastewater but suffer from high production cost. In this study, instead of using pre-formed MgO nanoparticles, we found that in-situ formed Mg(OH)2 from MgCl2 and NaOH reaction exhibited super high arsenate (As(V)) removal efficiency. Only 1.5 mmol/L of in-situ formed Mg(OH)2 could remove more than 95% As(V) within 10 min to make the As contaminated water (10 mg-As(V)/L) meet the municipal wastewater treatment standard, whereas MgO nanoparticles failed. The Mg-As sludge has an amorphous crystal structure while no Mg(OH)2 phase could be observed. As(V) existed uniformly within the sludge which was confirmed by elemental mapping. A precipitation-adsorption-coagulation mechanism might exist, which could relieve the restriction of limited surface area of solid MgO adsorbents. This study not only reveals an applicable method for efficient removal of trace level As(V) from water but also implies the huge potential of in-situ formed adsorbents in water treatment. [ABSTRACT FROM AUTHOR]

Low-cost and green preparation of efficient sorbents is critical to the removal of organic contaminants during water treatment. In this study, the co-pyrolysis of macroalgae and oyster shell was designed to synthesize nitrogen-doped porous biochars for sorption removal of atrazine from water. Oyster shell played a significant role in opening pores in macroalgae-derived biochars, resulting in the surface area of the macroalgae (Enteromorpha prolifera and Ulva lactuca) and oyster shell co-pyrolyzed carbonaceous as high as 1501.80 m2 g−1 and 1067.18 m2 g−1, the pore volume reached 1.04 cm3 g−1 and 0.93 cm3 g−1, and O/C decreased to 0.09 and 0.08, respectively. The sorption capacity of atrazine to nitrogen-doped porous biochars (the Enteromorpha prolifera, Ulva lactuca and oyster shell co-pyrolyzed carbonaceous) reached 312.06 mg g−1 and 340.52 mg g−1. Pore-filling, hydrogen bonding, π-π or p-π stacking and electrostatic interaction dominated the multilayer sorption process. Moreover, the nitrogen-doped porous biochars showed great performance in cyclic reusability, and the Enteromorpha prolifera, Ulva lactuca and oyster shell co-pyrolyzed carbonaceous sorption capacity still reached 246.13 mg g−1 and 255.97 mg g−1, respectively. Thus, this study suggested that it is feasible and efficient to remove organic contaminants with the nitrogen-doped porous biochars co-pyrolyzed from macroalgae and oyster shell, providing a potential green resource utilization of aquatic wastes for environmental remediation. Highlights: Nitrogen-doped porous biochars (NPBs) were derived from natural wastes. Oyster shell enhanced the micropore and mesopore structures of NPBs. Physical sorption dominated atrazine sorption onto the NPBs. [ABSTRACT FROM AUTHOR]

In the field of global water purification, the issue of marine oil spills represents a significant challenge. The use of phase-selective organogelators (PSOGs) as sorbent materials in oil spill remediation is a promising solution due to their environmental adaptability and high absorption capacity. However, there are limited reports on PSOGs that can be used in powder form for rapid phase-selective gelation of crude oils. In this context, the development of innovative dicholesteryl derivatives as low-molecular-weight organogelators (LMOGs) offers a promising solution in powder form. These gelators are synthesized through a one-pot multi-component reaction as green synthesis method, which ensures high purity and eliminates the need for harsh conditions. The incorporation of cholesterol into the gelator structure demonstrate environmental adaptability. The exceptional sorption capacity was attributed to the structured 2D/3D networks observed through scanning electron microscopy (SEM). The hydrophobic properties of these gelators, as evidenced by a water contact angle of 118 degrees, enable them to efficiently gel various organic solvents at low concentrations (1% w/v) at ambient temperatures, without the need for heating–cooling cycles or co-solvents. The eco-friendly nature and efficient oil–water separation capabilities of these gelators in powder form represent a significant advancement in global water purification efforts. [ABSTRACT FROM AUTHOR]

The rise in the world's population has led to an amplified need for fundamental requirements such as healthcare, shelter, and water. At the same time, human practices like agriculture, mining, and deforestation have resulted in challenges related to environmental sustainability and the contamination of water resources. As a result, access to safe drinking water has become a major challenge worldwide, and controlling water pollution is crucial. Several water treatment methods, including adsorption, nanotechnology, and membrane technology, have been developed to mitigate health and environmental impacts. However, many of these methods are too expensive, especially for people living in low-income countries. Additionally, some of the technologies are not very effective at removing pollutants, which exacerbates the problem. The physical, chemical, and biological approaches for treating water are categorized in this review, along with the benefits and drawbacks of each approach. Given that the adsorption method is thought to be one of the more economical and environmentally friendly techniques to treat water, this review recommends that in order to increase the efficacy of the adsorbents, a comprehensive investigation into the exact operation of the adsorbents at the cellular and molecular levels be conducted. [ABSTRACT FROM AUTHOR]

Peracetic acid (PAA) is efficient for disinfection processes in environmental sanitation and in the presence of transition metals its oxidative performance is enhanced. Thus, the present study aim evaluated the influence of Fe3+ ions during the inactivation process of Escherichia coli and Total Coliforms (TC). The process PAA + Fe3+ ions were also evaluated in relation to the disinfection kinetics, the participation of H2O2 and the influence of the organic load of the treated water. The tests showed an inactivation efficient of 0.5 to 0.9 log in relation to E. coli and 1.3 to 1.5 logs for TC in the concentrations evaluated and complete inactivation of E. coli was achieved within 15 min for both PAA and PAA/Fe3+ There is no damage to the disinfection process in the presence of Fe3+ ions, however, the decomposition of PAA is favored. In this sense, the formation of radicals can justify the maintenance of disinfection efficiency. The decay constants were close both microorganisms: for E. coli with PAA and PAA/Fe3+were 0.0323 and 0.0476 and for TC were 0.0637 and 0.0667. The values of R2 were above 0.95. Computer simulations of peptidoglycans that make up the bacterial cell wall showed that radicals preferentially attacked the carbons from the rings that composes the cell wall peptidoglycan of gram-negative bacteria allowing to break the structure during the disinfection process. [ABSTRACT FROM AUTHOR]

This work examines how graphene-based nanoparticles can be integrated into membranes to improve the effectiveness of water treatment in osmotic desalination processes. This is important since sustainable practices can help address the world's water scarcity. Water treatment, desalination, and resource recovery are areas where osmotic desalination shows great potential. However, membrane performance constraints frequently impede its efficacy. High mechanical strength, superior hydrophilicity, and the ability to lessen internal concentration polarisation are just a few of the remarkable qualities that make graphene-based nanoparticles stand out. In order to increase the membranes' overall functionality, these nanoparticles were created and added to them. Comparing the study to conventional membranes, the main goals were to increase water flux rates and salt ion rejection capacities. It was shown by experimental results that the membranes strengthened with graphene-based nanoparticles performed better. They outperformed conventional membranes in terms of water flow growth and salt ion rejection rates improvement. In order to advance osmotic desalination technologies towards more effective and sustainable water treatment options, this study highlights the revolutionary potential of graphene-based nanoparticles. Graphene-based nanoparticles provide an attractive option for tackling major water issues worldwide by improving membrane characteristics that are essential for osmotic desalination, such as permeability and selectivity. Water management techniques that are environmentally sustainable are supported by their integration into membranes, which also enhances performance metrics. This study opens the door for creative approaches to resource recovery and water treatment by providing important insights into the creation of cutting-edge materials specifically designed for osmotic desalination applications. [ABSTRACT FROM AUTHOR]

Treatment of heavy metal pollution in complexed states within water bodies presents significant challenges in the current water treatment field. Adsorption as a means for the removal of heavy metals is characterized by its simplicity of operation, stable effluent, and minimal equipment requirements. Metal–organic frameworks (MOFs) as adsorbents hold significant interest for applications in water treatment. In this study, we investigated a green synthesis approach for the ball-milling pretreated synthesis of UiO-66(Zr) at room temperature, abbreviated as UiO-66(Zr)-rm. Besides having the same thermal stability and crystal structure as the product from microwave-assisted synthesis (UiO-66(Zr)-mw), the resulting UiO-66(Zr)-rm features smaller particle size and superior mesoporous structure. The adsorption efficiency and mechanism for removing EDTA-chelated copper (EDTA–CuII), a complexed heavy metal in water, were extensively analyzed. UiO-66(Zr)-rm presented a maximum adsorption capacity over EDTA–CuII of 43 mg g−1 and a much higher adsorption rate (0.16 g (mg h)−1) than UiO-66(Zr)-mw (0.06 g (mg h)−1). Hierarchically mesostructured defects allow the sorbate to have more effective diffusion in a shorter time to achieve faster adsorption kinetics. Benefiting from the mild synthesis conditions and nontoxic solvents, UiO-66(Zr) has the potential to be produced at a scaled-up level, thereby exhibiting excellent adsorption performance for the removal of complexed heavy metals in the future. [ABSTRACT FROM AUTHOR]

Wastewaters consist of organic pollutants that have environmental concerns. Wastewaters are treated by different methods, but efficient, low-cost, and sustainable techniques still need to be developed. Algae-based water pollution remediation techniques are considered to be sustainable approaches. This review exclusively discusses the facets of macro and microalgae in the treatment of organic toxicants. The current trends of algae-mediated water treatments have been discussed under adsorption and degradation methods. A focus on algae fuel cell, algae mediated activation of oxidizing agents, Fenton-like reactions, and photocatalysis was given. The need of algae-based adsorptive and catalytic materials was mentioned. The role of algae in the synthesis of catalysts which were employed in pollutant removal methods was also explained. The integrated algae-mediated water treatment techniques were also highlighted. The toxicant removal performances of different algae-based materials in the water medium were summarized. The conclusion and future prospects derived from the literature survey were described. This review will be helpful for researchers who are working in the field of sustainable water pollution remediation. [ABSTRACT FROM AUTHOR]

Optimizing the fermentation process of microorganisms with exceptional bioflocculant-producing capabilities is crucial for the production of bioflocculants. The application of bioflocculants to various pollutants highlights their significant advantages in water treatment. Therefore, the culture conditions of Bacillus subtilis 35A with exceptional bioflocculant-producing capabilities were optimized. The bioflocculant (MBF) was obtained by alcohol percipitation from the fermentation supernatant, and its physicochemical properties were analyzed to explore its application in the treatment of dyes, heavy metal ions, and organic wastewater. The results indicate that, using cyclodextrin and yeast extract as carbon and nitrogen sources, after 48 h of fermentation at the initial pH, the bioflocculant (MBF-35A) yielded 10.47 g/L with a flocculation rate of 96.57% for kaolin suspension. The chemical analysis demonstrated that MBF- 35A is mainly composed of polysaccharide (81.74%) and protein (16.42%). FITR and XPS analysis indicated that MBF-35A mainly contains major elements such as carbon, nitrogen, and oxygen, with functional groups (-OH, C-O, C-H, and C-O-C) that are beneficial for flocculation. MBF-35A exhibited a dye decolorization efficiency exceeding 95% and removed 41.05 and 48.93% of Cr6+ and Cu2+ ions, respectively. In meat wastewater treatment, the effective removal rates of ammonia nitrogen (26.87%), COD (51.16%), total nitrogen (37.76%), and total phosphorus (55.81%) highlight its potential in organic waste treatment. In brief, not only does MBF-35A exhibit efficient production and excellent flocculation performance as a bioflocculant, but it also shows significant biological and environmental benefits in dye, heavy metal ions, and organic wastewater treatment. [ABSTRACT FROM AUTHOR]

The use of semiconductor‐based photocatalytic methods has been widespread for a range of applications, including pollution control and energy generation. However, certain analytical concerns limit the effectiveness of these photocatalysts, such as their limited light absorption capacity, physicochemical instability, and large energy band gap. To address these issues, scientists have been exploring integrating carbonaceous materials into photocatalytic systems to enhance their activity. This review focuses specifically on fullerene photocatalysts, a type of carbonaceous photocatalyst that has shown great promise in recent research. Fullerenes, which include C60 and C70, have unique properties that make them ideal for use as photocatalyst amplifiers in combination with other semiconductors or non‐semiconductors. This review summarizes recent research into the use of fullerene‐based materials for a variety of photocatalytic applications, including pollutant degradation, and hydrogen energy production. The efficacy of fullerene‐based photocatalysts is also discussed in recent breakthroughs in photocatalytic mechanisms and synthesis methods, focusing on pollution removal and hydrogen generation. Finally, the review addresses ongoing challenges and opportunities for fullerene‐based photocatalysts. The goal is to contribute to advancements in environmental protection and energy generation. [ABSTRACT FROM AUTHOR]

MIL‐88 MOFs have gained considerable attention as photocatalysts in environmental remediation due to their advantages such as stability, reusability, efficient light absorption, and charge separation capabilities. This study explores the potential of MIL‐88A, MIL‐88B, and NH2‐MIL‐88B for degrading the reactive orange 16 (RO16). MIL‐88 s were synthesized via solvo(hydro)thermal method and characterized using FTIR, PXRD, SEM, zeta potential, and UV‐DRS techniques. Photocatalytic degradations were conducted under UVA radiation, revealed a remarkable 93 % degradation rate. MIL‐88 s demonstrated exceptional performance and reusability, maintaining high efficiency even at 300 mg/L catalyst concentration. The photodegradation efficiencies of MIL‐88 A, MIL‐88B and NH2‐MIL‐88B for RO16 reach nearly 85 % within 120 minutes, 92 % within 60 minutes, 90 % within 75 minutes respectively. Even at a high initial concentration of 15 mg/L, the results underscore the significance of evaluating both initial efficiency and stability over multiple cycles, with MIL‐88B initially exhibiting the highest efficiency declining to 77 % by the fifth cycle, while MIL‐88 A maintained 54 % efficiency and NH2‐MIL‐88B sustained 72 % efficiency over the same period. Mechanistic elucidation identified O2⋅− and ⋅OH as the primary reactive radicals. This study is unique in being the first to explore the photocatalytic removal of RO16 using MIL‐88 s, providing a pioneering approach to sustainable water treatment. [ABSTRACT FROM AUTHOR]

This research investigates the synthesis of a hybrid nanomaterial, denoted as Ni‐Zn−S@Cyclodextrine, through a cost‐effective and easy co‐precipitation method. The resulting nanomaterial has been thoroughly characterized and applied for the adsorptive removal of Crystal violet and Congo red dyes from their solutions. The study delves into the thermodynamics and kinetics of the sorption process, as well as helps to propose adsorption mechanism for both the dyes onto the Ni‐Zn−S@Cyclodextrine surface. A comprehensive analysis, encompassing techniques, such as XRD, FTIR, SEM‐EDX, TEM, TGA, Zeta potential, and XPS, have been conducted to explore the structural and morphological attributes of the prepared nanomaterial. Furthermore, key sorption parameters, including adsorbent's dosage, temperature, contact time, and solution pH, have been systematically optimized to achieve maximum efficiency. The TEM images of prepared nanomaterial indicated the particle size ranging between 60–80 nm. Moreover, it exhibited a strong affinity for both the dyes, with a maximum adsorption capacity of 138.20 mgg−1 for Congo red and 129.95 mgg−1 for Crystal violet dyes at 303 K. The thermodynamics of the adsorption process indicated an endothermic and spontaneous nature. Isotherm studies revealed that the data best aligned with the Freundlich isotherm, while the kinetics of the reaction adhered to a pseudo‐second order within the investigated temperature range. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Photocatalysis is a promising green approach for water purification. The diversity of water pH values is a key factor that restricts its practical application since pH affects the adsorption of organic molecules, the stability of catalysts and photocatalytic performance. Here, we report a pH–independent, efficient and stable photocatalytic system with a liquid (water)–liquid (oil)–solid (semiconductor) (L–L–S) triphase interface microenvironment. The system is fabricated by coating a thin layer of silicon oil on the surface of ZnO nanowire arrays, a model chemically unstable semiconductor in both acidic and alkaline solutions. We show that the unique interface makes the dye adsorption pH independent and prevents the semiconductor from being corroded by strong acidic/alkaline solutions, leading to a stable and efficient photocatalytic reaction over a wide pH range (1—14). These findings reveal a promising path for the development of high‐performance catalysis systems applicable in complex water environments. [ABSTRACT FROM AUTHOR]

This study addresses the critical need for efficient and sustainable methods to tackle organic pollutants and microbial contamination in water. The present work aim was to investigate the potential of multi-structured zinc oxide nanoparticles (ZnO NPs) for the combined photocatalytic degradation of organic pollutants and antimicrobial activity. A unique fusion of precipitation-cum-hydrothermal approaches was precisely employed to synthesize the ZnO NPs, resulting in remarkable outcomes. The synthesized CTAB/ZnO NPs demonstrated exceptional properties: they were multi-structured and crystalline with a size of 40 nm and possessed a narrow band gap energy of 2.82 eV, enhancing light absorption for photocatalysis. These nanoparticles achieved an impressive degradation efficiency of 91.75% for Reactive Blue-81 dye within 105 min under UV irradiation. Furthermore, their photocatalytic performance metrics were outstanding, including a quantum yield of 1.73 × 10–4 Φ, a kinetic reaction rate of 3.89 × 102 µmol g–1 h–1, a space–time yield of 8.64 × 10–6 molecules photon–1 mg–1, and a figure-of-merit of 1.03 × 10–9 mol L J–1 g–1 h–1. Notably, the energy consumption was low at 1.73 × 10–4 J mol–1, compared to other systems. Additionally, the ZnO NPs exhibited effective antimicrobial activity against S. aureus and P. aeruginosa. This research underscores the potential of tailored ZnO NPs as a versatile solution for addressing both organic pollution and microbial contamination in water treatment processes. The low energy consumption further enhances its attractiveness as a sustainable solution. [ABSTRACT FROM AUTHOR]

Heavy metal ions can be introduced into the water through several point and non-point sources including leather industry, coal mining, agriculture activity and domestic waste. Regrettably, these toxic heavy metals may pose a threat to both humans and animals, particularly when they infiltrate water and soil. Heavy metal poisoning can lead to many health complications, such as liver and renal dysfunction, dermatological difficulties, and potentially even malignancies. To mitigate the risk of heavy metal ion exposure to humans and animals, it is imperative to extract them from places that have been polluted. Several conventional methods such as ion exchange, reverse osmosis, ultrafiltration, membrane filtration and chemical precipitation have been used for the removal of heavy metal ions. However, these methods have high operation costs and generate secondary pollutants during water treatment. Biosorption is an alternative approach to eliminating heavy metals from water that involves employing eco-friendly and cost-effective biomass. This review is focused on the heavy metal ions contamination in the water, biosorption methods for heavy metal removal and mathematical modeling to explain the behaviour of heavy metal adsorption. This review can be helpful to the researchers to design wastewater treatment plants for sustainable wastewater treatment. [ABSTRACT FROM AUTHOR]

Membrane materials that resist nonspecific or specific adsorption are urgently required in widespread practical applications, such as water purification, food processing, and life sciences. In water purification, inevitable membrane fouling not only limits membrane separation performance, leading to a decline in both permeance and selectivity, but also remarkably increases operation requirements, and augments extra maintenance costs and higher energy consumption. In this work, we report a freestanding interfacial polymerization (IP) fabrication strategy for in situ creation of asymmetric block copolymer (BCP) nanofilms with antifouling properties, greatly outperforming the conventional surface post‐modification approaches. The resultant free‐standing asymmetric BCP nanofilms with highly‐dense, highly‐hydrophilic polyethylene glycol (PEG) brushes on one side, can be readily formed via a typical IP process of a well‐defined double‐hydrophilic BCP composed of a highly‐efficient antifouling PEG block and a membrane‐forming multiamine block. The asymmetric BCP nanofilms have been applied for efficient and sustainable natural water purification, demonstrating extraordinary antifouling capabilities accompanied with superior separation performance far beyond commercial polyamide nanofiltration membranes. The antifouling behaviors of asymmetric BCP nanofilms derived from the combined effect of the hydration layer, electrostatic repulsion and steric hindrance were further elucidated by water flux and fouling resistance in combination with all‐atom molecular dynamics (MD) simulation. This work opens up a new avenue for the large‐scale and low‐cost creation of broad‐spectrum, asymmetric membrane materials with diverse functional "defect‐free" surfaces in real‐world applications. [ABSTRACT FROM AUTHOR]

In recent years, there has been growing interest in using polymer nanocomposite membranes as a more advanced method for removing pollutants from water and treating wastewater for various purposes. In this study, thin‐film nanocomposite (TFN) membranes of polycarbonate/polyvinyl alcohol–titanium dioxide thin‐film (PC/PVA–TiO2) were fabricated by dip‐coating a PC substrate in a PVA/TiO2 solution. Various methods, including attenuated total reflectance‐Fourier transform infrared (ATR‐FTIR) spectroscopy, field emission scanning electron microscopy (FE‐SEM), atomic force microscopy (AFM), and water contact angle were utilized to assess the structural characteristics of the produced membranes. The PC/PVA thin‐film composite (TFC) and PC/PVA–TiO2 TFN membranes were then examined in a submerged membrane system to evaluate their effectiveness in filtering humic acid (HA) under various vacuum transmembrane pressure (0.3 and 0.6 bar) condition. The FTIR‐ATR results confirmed the formation of the active layer of PVA/TiO2 nanoparticles (NPs). It was observed that adding 1 wt.% of TiO2 NPs to the active layer of PVA/TiO2 significantly enhanced the water contact angle from 77.5° for PC support to 55.3° for PC/PVA–TiO2 (0.1) TFN membranes. Furthermore, the FE‐SEM results confirmed the formation of an active layer of PVA/TiO2 with a thickness of 237.87 nm. The pure water flux increased from 101.64 L/m2h for the PC/PVA TFC membrane to 144.02 L/m2h and 199.09 L/m2h for the PC/PVA–TiO2 (0.05) and PC/PVA–TiO2 (0.1) TFN membranes, respectively. Also, the results revealed that at lower transmembrane pressure, all membranes showed higher value in HA removal as compared to when higher transmembrane pressure was used. [ABSTRACT FROM AUTHOR]

The constant increase in population and as a result increase in industrial activities in many areas, such as textiles, cosmetics, leather, polymers, and food processing leads to the contamination of water sources with different dyes. Thus, the removal of dyes from contaminated water sources to make water reusable is the utmost requirement of the time in order to get environmental sustainability. The reason of removal is that many dyes and pollutants present in dyeing wastewater from industries have detrimental impacts on plants, wildlife, and humans. To lessen the negative effects of dye wastewater on the environment and living beings, it should be processed first to remove un-wanted components before being released in the water sources. However, due to some drawbacks of dye removal technologies, it is challenging to settle on a single solution that addresses the current dye effluent problem to make water clean. In the current work, we tried our best to elaborate different methods adopted for the treatment of dyes polluted wastewater with respect to their implementation along with drawbacks and advantages. [ABSTRACT FROM AUTHOR]

Interfacial solar evaporation, harnessing sunlight to induce water molecule evaporation, holds great promise for sustainable solar energy conversion. However, challenges such as reduced efficiency and instability due to salt accumulation, inadequate water transport, and the high cost of advanced nanostructured solar evaporators collectively hinder the sustainable and large‐scale practical use of this technology. Herein, an eco‐friendly, floatable 3D solar seawater evaporator is developed by innovatively incorporating a lightweight foam ball enclosed in a porous cellulose hydrogel. The 3D evaporator achieves a high water evaporation rate of ≈2.01 kg m−2 h−1 under 1 Sun, owing to its super high photothermal efficiency of 117.9% and efficient internal water transport channels. Even at a 0° simulated solar angle, the 3D evaporator maintains 85.8% of the evaporation rate at a 90° simulated solar angle. Moreover, the salt self‐cleaning capability is realized by the autonomous rotation caused by salt deposition. Particularly, the 3D evaporator can be fabricated over a large area and maintain seawater evaporation performance and structural integrity for 28 days. This study provides novel economically feasible and sustainable large‐scale solutions for interfacial solar‐powered seawater treatment. [ABSTRACT FROM AUTHOR]

Effluent reuse is a rapidly growing field of research where assessing the quality of effluent is one of the focus areas. This research examines the viability of using wastewater in agriculture by testing an integrated Upflow Anaerobic Sludge Blanket (UASB) reactor with a trickling filter (TF) system during the dry season. Compliance monitoring was conducted for 30 days from May 11 to June 9 of 2021. Samples were collected, handled, and analyzed following standard wastewater analysis procedures for biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), volatile suspended solids (VSS), cations, anions, heavy metals, E. coli, and helminth egg. The UASB-TF system in Kality wastewater treatment performed well in removing COD, BOD5, and TSS with average removal rates of 80.5%, 82.9%, and 80.9%, respectively, compared well with similar treatment configurations. The effluent quality satisfied the national inland discharge limit with a residual concentration of 125.1 mg/L for COD, 61.7 mg/L for BOD5 and 85.8 mg/L for TSS. On the other hand, high concentrations of chromium, nitrate-nitrogen, and helminth egg count restricted effluent reuse for agricultural purposes due to high health risks and environmental contamination. We found out that discharging industrial sewage into the domestic sewer network could inhibit microbial growth and affect the biological treatment processes. Furthermore, adopting integrated treatment systems in developing countries might face operational challenges and monitoring nitrate, helminth egg, and heavy metals would help provide timely operational feedback. An appropriate tertiary treatment unit—constructed wetlands or polishing ponds—is therefore needed to be introduced to ensure effluent reuse for agricultural purposes. [ABSTRACT FROM AUTHOR]

Japanese anchovy Engraulis japonicus is a small-sized fish, and it is difficult to obtain its flesh by hand. To enhance the utilization of this fish, this study aims to determine the effect of extraction methods on the amino acid, mineral, and fatty acid profile of recovered protein (RP) from Japanese anchovy, as well as the functional properties of RP. The protein was extracted from minced fish by three methods, including salt water treatment (RP-S) and pH-shifted processes at both acidic (RP-A) and basic (RP-B) solubilization. All RPs had more total essential amino acids than minced fish. Among RP, the highest Na and Fe content was found in RP-S, whereas RP-A showed the highest calcium content. RP-S possessed a lower amount of total polyunsaturated fatty acids than that of RP-A and RP-B. Water- and oil-absorption capacity and foam stability of RP-S and RP-B were on the same level and higher than those of RP-A. The highest emulsion activity index and emulsion stability index was found in RP-B. However, no difference was found in emulsion stability index between RP-S and RP-A. Overall, salt water treatment indicated that this method can be used as an alternative method to recover protein from Japanese anchovy. [ABSTRACT FROM AUTHOR]

Growing concern over potential ecotoxicological problems caused by micropollutants (MPs) in water has led to the application of adsorptive and oxidative advanced treatment technologies at European wastewater treatment plants (WWTPs). Direct dosage of gaseous ozone via diffusers or pump-injection systems is the most common large-scale process applied in water and wastewater treatment. Studies point out that MP removal may take place via the direct, very selective reaction with the ozone molecule as well as the indirect reaction with the very reactive but nonselective hydroxyl radicals. Several process parameters and set-ups may affect the MPs elimination and inhibit or even cause the formation of transformation products (TPs) such as bromate. This work compares an alternative ozone application procedure (the so-called 'ozone strong water' dosing – OSW) with standard systems regarding MP elimination, ozone consumption, reaction time, and required plant space. A full-scale OSW system was installed and operated at the WWTP Duisburg-Vierlinden. A significant reduction in the time required to achieve the maximum possible elimination was observed for all six MPs investigated, with a hydraulic reaction time of 8 min. According to a theoretical calculation, the reactor volume could be reduced by two-thirds of the installed volume. [ABSTRACT FROM AUTHOR]

In this research work, a real case of failed ASTM A860 WPHY 65 long elbow pipe coated with inorganic zinc ethyl silicate primer is collected from a treatment facility to investigate the root causes of its failure, which was reported after approximately 28 months of use. The failure was investigated using visual observations, metallurgical analysis using optical emission spectroscopy, mechanical testing, X‐ray diffraction of corrosion product, chemical analysis of sewage and corrosion rate test of the elbow using a three‐electrode potential technique, fractographic analysis using scanning electron microscope along with computational analysis to confirm the results. Through the testing, it was observed that severe depletion in the strength can be attributed to erosion–corrosion caused by various impurities present in the sewage, leading to the generation of corrosion pits and turbulent eddies and stresses generated due to sudden changes in fluid flow direction along with gases present in sewage reacting with a base metal. Various failure mechanisms that have led to pipe failure are discussed in this paper, along with a listing of preventive measures to delay it. [ABSTRACT FROM AUTHOR]

Accurate and efficient identification of pollution sources is a key process that assists in the treatment of water pollution incidents. The ensemble Kalman filter (EnKF) has been proven to be an effective approach for identifying pollution source parameters (e.g., source location, release time, and mass released). In this paper, a method involving multiple observations of reconstruction (MOR) is proposed for reconstructing multidimensional state vectors for assimilation based on pollutant concentration monitoring techniques. The newly reconstructed state variables have dimensionless characteristics that decouple the source mass from the parameter group to be identified before assimilation is performed. This approach can mitigate the interference of assimilation caused by nonmain source parameters. As a result, the pollution sources and material dispersion coefficients can be simultaneously identified at limited observation sites. Then, a set of synthetic numerical examples with 7 scenarios is assembled to investigate and compare the unique characteristics of the derived state variables during assimilation. A laboratory experiment for unknown parameter identification based on monitoring the chemical oxygen demand (COD) concentration is carried out in an annular flume to verify the applicability of the method in real events. The results show that the EnKF combined with the MOR method based on the decoupling pattern performs well in identifying pollution sources and dispersion coefficients simultaneously. The method can still perform excellently in identifying parameters in practice when some data in the observation sequences are lost, with relative errors of pollution source parameters being controlled within 4%. The relative errors of the identified transverse and longitudinal dispersion coefficients are 39% and 12%, respectively. Overall, by evaluating the original data, reconstructing the dataset, and combining it with the EnKF method, it is proven that the MOR–EnKF method is an effective measure for identifying high-dimensional unknown parameter groups. [ABSTRACT FROM AUTHOR]

[Display omitted] Two-dimensional (2D) transition metal carbides/nitrides, MXenes (in particular Ti 3 C 2 T x), and three-dimensional (3D) structures such as polymeric hydrogels or aerogels, are promising families of materials, each in their own right, with advantageous properties for applications in biomedicine, water treatment, electronic devices, and energy. Combination of MXenes with hydro- or aerogels may further improve their individual properties and impart new characteristics. Potentially, it can also significantly improve the chemical stability of MXenes, which is currently one of the main limiting factors for their widespread use. In this paper, we review some representative fabrication techniques and properties of Ti 3 C 2 T x MXene/3D hydrogel and aerogel composites, as well as selected applications of these composites for energy storage and harvesting, biology and medicine, water treatment, and EMI shielding. [ABSTRACT FROM AUTHOR]

Summary: The effect of 4 °C water cooling treatment after extrusion for different time (0 s, 30 s, 1 min, 3 min, and 5 min) on the structure and cooking characteristics of frozen extruded whole buckwheat noodles were investigated. The cooking time and cooking loss of frozen extruded whole buckwheat noodles significantly decreased after water cooling, and the broken rate was kept constant at 0%, indicating that the quality of frozen noodles was significantly improved. When the time for water cooling was 30 s, the noodles had the lowest cooking loss of 4.07% and the highest hardness and springiness of 3993.19 g and 0.96, respectively. X‐ray diffraction results showed that water cooling treatment increased the crystallinity of starch, and the amylose underwent short‐term ageing. It was also observed from a scanning electron microscope that the gel network structure of the noodles treated with 30 s water cooling was more complete and uniform. Differential scanning calorimetry analysis showed that the water cooling treatment significantly increased the freezable water content. Meanwhile, low‐field nuclear magnetic resonance indicated that the water mobility in the noodles was weakened. The above results showed that 4 °C water cooling treatment for 30 s was beneficial to the formation of starch gel structure and improved the quality of frozen noodles. This study provides a new approach to improve the quality of extruded whole buckwheat noodles. [ABSTRACT FROM AUTHOR]