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Corn-like ZnO/Ag2S heterojunctions are designed and prepared by the solvothermal method and the subsequent covering process. They construct a type II core–shell heterojunction structure. This structure adjusts the relative positions of electron energy levels and generates a strong and broad absorption band, while emitting weak visible light. It also facilitates the transfer of photoexcited carriers through the interface and the confinement of the same by the different components of the nanostructure. Separation of electrons and holes makes them possible to drift to the surface of ZnO and Ag2S and to participate in the redox reactions. In addition, the presence of many defects produces many active sites on the surface of the lattice. So, the ZnO/Ag2S heterojunctions exhibit excellent photocatalytic properties in the first and second cycles of the photocatalytic process. It degrades 97.7% Rhodamine B only in 18 min. This study plays a significant role in promoting visible light catalysis, the efficiency of wastewater treatment technology, and the water environment on the earth. [ABSTRACT FROM AUTHOR]

In this work, pure and S–N/WO3 (1%–7%) nanoparticles (NPs) have been developed for the degradation of MB dye. Optical properties, vibrational analysis, morphology, structural analysis, and photocatalytic activity of the samples have been evaluated using a variety of characterization techniques, including UV–vis, PL, FTIR, SEM, and x-ray diffraction (XRD). The XRD patterns showed that the stability of the orthorhombic phase of WO3 was affected by the concentrations of S and N. In SEM, nanospheres with an average size of 80 nm of NPs have been observed. The PL results showed that the e−, h+ recombination rate for the S–N7%/WO3 sample was the lowest. The degradation of MB dye has also been investigated in order to investigate the photocatalytic performance. Remarkably, S–N7%/WO3 shows the best results, with a maximum degradation of 90% in 120 min. The stability of the improved catalyst was tested using recycling and trapping studies. S–N7%/WO3 catalyst's exceptional photocatalytic activity highlights its potential use in wastewater treatment. This study will be helpful for manufacturing innovation. [ABSTRACT FROM AUTHOR]

Semiconductor-based photocatalysts have become increasingly used in the removal of pollutants from wastewater, especially antibiotics. A series of composite-based cuprous oxide and bismuth vanadate (Cu2O/BiVO4) composite-based photocatalysts were synthesized by using the chemical method. The structure of the Cu2O/BiVO4 composite was verified by using x-ray diffraction, scanning electron microscopy, photoluminescence, Fourier transform infrared spectroscopy, and UV–visible spectra. The degradation of methylene blue (MB) and tetracycline (TC) was investigated to check the photocatalytic activity of the Cu2O/BiVO4 composite series. The quantity of Cu2O was varied from 1% to 7% by weight to prepare the series of Cu2O/BiVO4 composites. The analysis of results verified that 5% Cu2O/BiVO4 exhibits an outstanding photocatalytic activity as compared to 1%, 3%, and 7% Cu2O/BiVO4, pure Cu2O, and pure BiVO4 under visible light irradiation. The optimum value of photocatalytic degradation achieved with 5% Cu2O/BiVO4 was 97% for MB dye and 95% for TC in 120 min, which is greater than the photocatalytic degradation of pure BiVO4 (MB 45% and TC 72%), pure Cu2O (MB 57% and TC 80%), 1% Cu2O/BiVO4 (MB 72% and TC 85%), 3% Cu2O/BiVO4 (MB 83% and TC 88%), and 7% Cu2O/BiVO4 (MB 87% and TC 91%). The stability and reusability of Cu2O/BiVO4 were also investigated. To check the major role of trapping in degradation, a trapping experiment was also performed by using three trapping agents: BQ, EDTA, and tBuOH. The results showed that Cu2O/BiVO4 exhibits an improved photocatalytic activity in the degradation of antibiotics in polluted water because the recombination rate of the electron–hole pair decreased and the surface area increased, which increased the active sites for redox reactions. Such a photocatalytic composite with high efficiency has various applications, such as energy production, environmental remediation, and water remediation. [ABSTRACT FROM AUTHOR]

Modelling of many real-world processes, such as drug delivery, wastewater treatment, and pharmaceutical production, requires accurate descriptions of the dynamics of hard particles confined in complicated domains. In particular, when modelling sedimentation processes or systems with driven flows, it is important to accurately capture volume exclusion effects. This work applies Dynamic Density Functional Theory to the evolution of a particle density under diffusion, external forces, particle–particle interaction, and volume exclusion. Using a spectral element framework, for the first time it is possible to include all of these effects in dynamic simulations on complex domains. Moreover, this allows one to apply complicated no-flux, and other non-local, non-linear, boundary conditions. The methodology is also extended to control problems, addressing questions of how to enhance production set-up in industrially-motivated processes. In this work the relevant models are introduced, numerical methods are discussed, and several example problems are solved to demonstrate the methods' versatility. It is shown that incorporating volume exclusion is crucial for simulation accuracy and we illustrate that the choice of boundary conditions significantly impacts the dynamics. [ABSTRACT FROM AUTHOR]

Peach (Prunus persica) is consumed in almost every part of the world due to its unique taste, flavor, and other sensorial characteristics. The peach processing industry discarded many parts of the fruit including stone, seed, and peel as "peach waste" (PW) after separating the fleshy part of the fruit. PW components are an affluent source of protein, micronutrients, bioactive compounds, hemicellulose, lignin, and cellulose. This proffer review potentially identifies nutraceutical exploitation with health benefits demonstrated by functional bioactive compounds along with their industrial applications in the field of nutraceuticals, food, feed, and cosmetics. Moreover, Wastewater treatment and biosynthetic development of practically useful products are also discussed. The use of PW for the development and designing of innovative nutraceutical and functional foods with enhanced quality could also be significant for lowering food waste and improving food security and sustainability. [ABSTRACT FROM AUTHOR]

Current photocatalysts endowed with oxidation and reduction capabilities for pharmaceuticals and heavy metals removal face numerous challenges, such as a lack of sufficient reactive sites, poor electron-hole separation, and limited oxidation and reduction capabilities. In this study, we aimed to overcome these limitations by employing a simple solvothermal method to fabricate a novel S-scheme heterojunction, Cd 0.5 Zn 0.5 S/CeO 2. The optimal Cd₀.₅Zn₀.₅S/CeO 2 heterojunction achieved a maximum ciprofloxacin degradation efficiency of 86 % within 30 min, showing a remarkable improvement of 2.4 and 4.6 times compared to pristine Cd₀.₅Zn₀.₅S and CeO 2 , respectively. The heterojunction also demonstrated a remarkable 100 % photoreduction efficiency of Cr(VI) within 30 min, which is double the photodegradation performance of the individual materials. The combination of Cd₀.₅Zn₀.₅S with CeO 2 to form the Cd₀.₅Zn₀.₅S/CeO 2 S-scheme heterojunction effectively enhanced spatial photo-carrier separation and optimized the photo-redox capability, resulting in a substantial improvement in photocatalytic performance and stability. Through radical trapping experiments, the primary reactive species responsible for CIP degradation were identified as h⁺, OH•, and •O₂⁻. Additionally, e⁻ was determined to be the key species responsible for the photoreduction of Cr(VI). Based on these findings, we proposed a plausible photocatalytic reaction pathway for the simultaneous elimination of both CIP and Cr(VI). This study underscores the significant potential of the Cd 0.5 Zn 0.5 S/CeO 2 S-scheme heterojunction for advanced wastewater treatment applications, highlighting its innovative approach and superior performance. [ABSTRACT FROM AUTHOR]

Among different pollutants, organic dyes, phenolic compounds, and antibiotics are three types of hazardous contaminants that have become serious environmental issues. This work deals with the synthesis of new visible-light responsive CsM 0.25 W 1.75 O 6 (M = Ni, Co, Mn, Cu) compounds with a solid-state reaction induced defect pyrochlore structure followed by crushing in a ball mill. The prepared materials were characterized using scanning electron microscopy, X-ray diffraction with Rietveld refinement, X-ray photo-electron spectroscopy, differential thermal analysis, and nitrogen adsorption-desorption measurements at low-temperature. The optimized CsNi 0.25 W 1.75 O 6 (CsNiWO-2) compound was tested for its photocatalytic abatement efficient for several contaminants including methylene blue, phenol, as well as levofloxacin and isoniazid antibiotics. The influence of the various key aspects, such as photocatalyst dosage and hydrogen peroxide concentration, on the degradation efficiency of CsNiWO-2 was examined. The degradation efficiency of CsNiWO-2 (0.6 g L−1) towards methylene blue, phenol, levofloxacin, and isoniazid in the presence of H 2 O 2 (0.06 mol L−1) was 81.4, 47.9, 84.6, and 37.4 %, respectively. Thus, the developed material demonstrates promising properties to degrade methylene blue and levofloxacin. Also, the mechanism and comprehensive schemes for the photooxidation of methylene blue and levofloxacin were elucidated over CsNiWO-2. The present research potentially contributes to designing efficient defect pyrochlores for wastewater treatment under visible light irradiation. [Display omitted] • CsM 0.25 W 1.75 O 6 (M = Ni, Co, Mn, Cu) materials were prepared by a solid-state method. • First report of CsM 0.25 W 1.75 O 6 (M = Ni, Co, Mn, Cu) photodegradation activity. • Grinded CsNi 0.25 W 1.75 O 6 displayed highest activity in the degradation of MB and LFX. • Potential of CsNi 0.25 W 1.75 O 6 photocatalyst for wastewater treatment under LED light. [ABSTRACT FROM AUTHOR]

Cellulose‐based "biomass" adsorptive materials have gained significant attention because of their effectiveness in various applications. In this study, a cellulose composite aerogel with a rich three‐dimensional network structure, low density, and high porosity was successfully obtained by the in situ self‐polymerization of dopamine (DA) and acrylamide (AM) in an alkaline urine system. Fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray photoelectron spectroscopy, elemental analysis, and other analytical techniques were used to analyze the physical and chemical structures of the cellulose composite aerogels. The results revealed that the introduction of DA and AM into the aerogel enhanced the adsorption and mechanical properties of the active sites, thereby boosting adsorption capacity and recyclability. By optimizing the adsorption of methylene blue (MB) dye using a cellulose composite aerogel, a maximum adsorption capacity of 406.89 mg g was obtained. The MB dye adsorption curve of the cellulose composite aerogel conformed to the Langmuir model, which indicates high adsorption capacity and recyclability. This confirms the high application potential of the cellulose composite aerogel in wastewater treatments. [ABSTRACT FROM AUTHOR]

This review comprehensively examines the various applications of microalgae, focusing on their significant potential in producing biodiesel and hydrogen, serving as sustainable food sources, and their efficacy in treating both municipal and food-related wastewater. While previous studies have mainly focused on specific applications of microalgae, such as biofuel production or wastewater treatment, this review covers these applications comprehensively. It examines the potential for microalgae to be applied in various industrial sectors such as energy, food security, and environmental management. By bridging these different application areas, this review differs from previous studies in providing an integrated and multifaceted view of the industrial applications of microalgae. Since it is essential to increase the productivity of the process to utilize microalgae for various industrial applications, research trends in different microalgae cultivation processes, including the culture system (e.g., open ponds, closed ponds) or environmental conditions (e.g., pH, temperature, light intensity) to improve the productivity of biomass and valuable substances was firstly analyzed. In addition, microalgae cultivation technologies that can maximize the biomass and valuable substances productivity while limiting the potential for contamination that can occur when utilizing these systems have been described to maximize CO2 reduction. In conclusion, this review has provided a detailed analysis of current research findings and technological innovations, highlighting the important role of microalgae in addressing global challenges related to energy, food supply, and waste management. It has also provided valuable insights into future research directions and potential commercial applications in several bio-related industries, and illustrated how important continued exploration and development in this area is to realize the full potential of microalgae. [ABSTRACT FROM AUTHOR]

Industrial wastewater treatment using UV irradiation in combination with oxidants or catalysts (TiO2) has attracted attention as a promising substitute for conventional methods. Studying the preparation and characterization of TiO2–SnO2 nanocomposites with different ratios, as well as their use in the enhanced photocatalytic degradation of acid red 37 dye in aqueous solution under UV irradiation as a model pollutant, are the goals of the research. The crystalline structures of the prepared nanomaterials were confirmed by XRD and the surface morphology of the samples was studied by TEM. The elemental compositions of the catalysts were confirmed by EDAX. The optical properties of the powder samples were analyzed with UV–Vis spectroscopy and their band gaps were estimated. The photocatalytic degradation was investigated using several advanced oxidation techniques using a batch photoreactor. The TiO2–SnO2 (90:10) nanocomposite showed the best degradation efficiency. [ABSTRACT FROM AUTHOR]

One of the biggest problems in the ecosystem is wastewater contaminated with industrial dyes. These pollutants have a very stable chemical structure, which causes complicated removal. However, a possible alternative for wastewater treatment is zinc oxide semiconductor nanoparticles (ZnO NPs). The approach of this study was the implementation of a green synthesis methodology for the obtention of ZnO nanoparticles employing Ipomoea stans (TV) leaves as extracts. The properties of the ZnO nanoparticles synthesized at 1 %, 2 %, and 4 % w/v (weight/volume) concentration of the extract were obtained from the characterization using different techniques. The FTIR analysis determined the presence of the active functional groups attached to the surface, which capped and stabilized the ZnO NPs; a band located in the range of 500-390 cm−1 confirms the presence of the Zn–O bond. The UV absorption spectra of all ZnO NPs samples were determined by executing the ultraviolet–visible spectroscopy technique, with a characteristic signal located at ∼370 nm and energy gap values between 3.036 eV and 3.101 eV. In addition, XRD patterns determined the average crystallite sizes to be 30.78 nm for ZnO-TV 1 %, 18.68 nm ZnO-TV 2 %, and 11.96 nm ZnO-TV 4 %, respectively. Furthermore, the results from transmission electron microscopy (TEM) displayed the following values of mean particle size of 21 nm, 24.4 nm, and 10.16 nm for ZnO-TV 1 %, ZnO-TV 2 % and ZnO-TV 4 % with S.D. 9.10, 12.5 and 3.6. Finally, the photocatalytic activity was evaluated utilizing the industrial dyes Methyl Orange, Methylene Blue, Rhodamine B, Malachite Green, and Congo Red. Obtaining outstanding results in the degradation of all industrial dyes. All syntheses achieved degradation greater than 91 % for methyl orange, methylene blue, and rhodamine B. [ABSTRACT FROM AUTHOR]

Abstract\nHIGHLIGHTSNowadays due to rapid industrialization to assist humans, hazardous and non-biodegradable dyes are eliminated from leather and textile industries in water streams. To eradicate these toxic dyes, the adsorption process opted for wastewater reclamation. Therefore, polyacrylamide-based hydrogels were fabricated using methylene Bis acrylamide and FeCl3 as chemical and physical cross-linkers. Sodium alginate-co-Polyacrylamide-co-acrylic acid a ter-copolymer hydrogel cross-linked via N, N’ˊ methylene bisacrylamide shows maximum %swelling at pH 9 i.e. 751.42% and an equilibrium time of 200 min. The sorption capacity obtained for ASM0.1 was maximum i.e. 43.809 ± 0.569 mg/g as compared to the sorption capacity of AAM0.05 and AAF0.05 i.e. 41.18 ± 0.541 mg/g and 35.588 ± 0.924 mg/g. The kinetic model followed by sorption of methylene blue onto polyacrylamide-based hydrogels was pseudo-second-order whereas diffusion occurred in two phases through macropores and mesopores. The optimized pH recorded for sorption is pH 9 having an adsorption value of 94.16 ± 1.326 mg/g. Batch experiments revealed that adsorption increases from 37.52 ± 0.743 mg/g to 104.56 ± 1.194 mg/g for ASM 0.1 with an increase in concentration from 20 mg/L to 60 mg/L. The isotherm model followed by MB sorption is the Freundlich isotherm model which infers the physical nature of sorption. Moreover, with an increase in temperature, the adsorption slightly increased from 89.31 mg/g to 92.14 mg/g due to an increase in kinetic energy with temperature rise. % Removal stability was investigated for 5 consecutive cycles and inferred that ASM0.1 has decreased its % removal by only 6.5% after five cycles.Synthesis of sodium alginate-co-polyacrylamide-co-acrylic acid via free radical addition polymerization.FT-IR analysis reveals the successful formation of polyacrylamide-based hydrogels w.r.t. chemical and physical cross-linking.Pseudo-second order kinetic model is followed by sorption of methylene blue on synthesized hydrogel.Isotherm model and ΔH value calculated infer the physio-sorption of MB on polyacrylamide-based hydrogels.Synthesis of sodium alginate-co-polyacrylamide-co-acrylic acid via free radical addition polymerization.FT-IR analysis reveals the successful formation of polyacrylamide-based hydrogels w.r.t. chemical and physical cross-linking.Pseudo-second order kinetic model is followed by sorption of methylene blue on synthesized hydrogel.Isotherm model and ΔH value calculated infer the physio-sorption of MB on polyacrylamide-based hydrogels. [ABSTRACT FROM AUTHOR]

Wastewater from many food and beverage manufacturers is enriched in organic content, and it must therefore be treated before being discharged to comply with the strict environmental regulations to protect the final water quality. Concretely, the honey processing wastewater, that remains in holding tanks until is disposal, is a rich source of sugars and this high level of organic material will degrade the water quality if not treated properly provoking an imbalance in the ecosystem. There are different strategies for an adequate treatment of this wastewater effluent to obtain a sustainable usage. One of the techniques that is more cost-effective and environmental friendlier than chemical procedures used for water remediation, is the use of microorganisms (including algae, fungi, yeasts, or bacteria). Given that they are fast-growing, robust, and metabolically diverse, yeast strains are often used for wastewater treatment. In this work, we have studied the potential for bioremediation of non Saccharomyces yeast isolated from a honey processing wastewater generated by an Argentine exporting company. The inoculation of these yeast strains to the existing flora in the honey wastewater yielded a better improvement in the treatment yield. These results suggest that these strains display a promising role could for optimizing bioremediation strategies in industrial wastewater treatment processes. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTThis study addresses the environmental challenge posed by the invasive Prosopis juliflora plant by converting its stem into activated carbon for the adsorption of Methylene Blue dye from water. The goal is to create an effective and sustainable wastewater treatment solution. Prosopis juliflora stems were harvested, cleaned, dried, carbonized, and activated with zinc chloride to create Prosopis Juliflora Stem Activated Carbon. This activated carbon was characterized using Brunauer-Emmett-Teller surface area analysis, Fourier transform infrared spectroscopy, and scanning electron microscope imaging. Results revealed a significant surface area of 158.107 m2/g and the presence of functional groups essential for adsorption processes. Batch adsorption experiments were conducted to determine the efficiency of activated carbon in removing Methylene Blue dye at various dosages and contact times. The highest adsorption efficiencies were 73.5% at 80 min, 90.1% at 60 min, and 90.65% at 50 min for dosages of 80, 100, and 120 mg, respectively. These findings show that Prosopis Juliflora Stem Activated Carbon is highly effective at removing Methylene Blue dye, providing a cost-effective and environmentally friendly method of wastewater treatment.The novelty of this study lies in the inventive use of Prosopis juliflora stem, an invasive species, to produce an environmentally sustainable and economical activated carbon for the adsorption of Methylene Blue dye from polluted water. This method not only mitigates the environmental issues associated with the extensive proliferation of Prosopis juliflora but also provides a sustainable solution for wastewater management. The work utilizes zinc chloride for activation and characterizes the carbon using modern techniques, including BET surface area analysis, FTIR spectroscopy, and SEM imaging, offering essential insights into the adsorption effectiveness and surface chemistry of the activated carbon. This work uniquely combines the control of an invasive species with the improvement of water purification procedures, so making a substantial contribution to environmental management and water treatment technology, distinguishing it from traditional adsorbent studies. [ABSTRACT FROM AUTHOR]

A novel heterotrophic, cold-tolerant bacterium, designated Pseudomonas zhanjiangensis 25A3ET, was isolated from mangrove sediment and demonstrated excellent efficiency in cold wastewater treatment. Phylogenetic analysis based on 16S rRNA gene sequences positioned strain 25A3ET within the genus Pseudomonas , showing the highest similarity (98.7%) with Pseudomonas kurunegalensis LMG 32023T. Digital DNA–DNA hybridization (dDDH) and average nucleotide identity (ANI) values were below the species delineation thresholds (70% for dDDH, 95% for ANI), indicating that strain 25A3ET represents a novel species. This strain demonstrated high efficiency in removing nitrogen (N) and organic pollutants under low-temperature conditions. Specifically, it achieved 72.9% removal of chemical oxygen demand (COD), 70.6% removal of ammoniacal nitrogen (NH4+-N), and 69.1% removal of total nitrogen (TN) after 96 h at 10°C. Genomic analysis identified key genes associated with cold adaptation, nitrogen removal and organic matter degradation. These findings indicate that Pseudomonas zhanjiangensis 25A3ET holds significant potential for application in cold temperature wastewater treatment, offering a promising solution for environmental remediation in regions with low ambient temperatures. [ABSTRACT FROM AUTHOR]

In this study, biochar modified with sulfur nanoparticles (SNPs@BC) was synthesized in terms of providing a low-cost adsorbent for cadmium and lead adsorption. Morphology and structure of SNPs@BC were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). And also, thermal gravimetric analysis (TGA) was used to study the thermal stability of the synthesized adsorbent. The results indicated that the biochar surface was successfully coated with sulfur nanoparticles and could improve its performance as a soil amendment or an adsorbent. Cadmium and lead adsorption studies on SNPs@BC exhibited high Langmuir cadmium (97 mg/g) and lead (99 mg/g) adsorption capacity, and heavy metal toxicity can be reduced by adsorption of cadmium and lead on SNPs@BC. The seed germination rate and seedling growth in cadmium-lead adsorbed SNPs@BC were the same as in the cadmium-free and lead-free control groups. This study suggests that SNPs@BC can be used as an efficient and eco-friendly sorbent for heavy metal removal. [ABSTRACT FROM AUTHOR]

During the past few decades, interest in phenolic substances in aquatic environments has increased due to their wide uses in numerous industries despite their high toxicity. This study aimed to investigate removing phenol from contaminated wastewater using synthesized nanoscale-activated carbon (AC) as a sorbent. The AC was synthesized from reed stalks as a local bio-based material using a chemical activation approach. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) in addition to the Fourier transform-infrared spectroscopy (FTIR) were applied to characterize the synthesizedAC. The study tested four different factors using the experimental statistical design, data analysis with Design Expert Software, and a central composite design (CCD) using response surface methodology (RSM) to maximize phenol elimination. These factors involved initial phenol concentration (ranging from 30 to 120 ppm), pH levels (ranging from 2 to 11), concentration of adsorbent range from 50 to 600 ppm, and reaction time range from 30 to 120 minutes. These variables were used as input data for the prediction model to determine the removal efficiency (%) of phenol. The analysis of the ANOVA was conducted to examine the model performance. The analysis results suggested that the most effective model in explaining the process of phenol elimination was the second-order quadratic model, and the predicted data strongly matched the experimental values. The findings revealed that the optimal adsorption conditions obtained from the experimental work were initial phenol concentration of 30 mg·L-1 , adsorbent dose of 600 mg·L-1, pH equal to 2, reaction time of 120 minutes, and the capacity of the adsorption was 30.0825 mg·g-1. As a consequence, the nanoactivated carbon extracted from reed stalks effectively adsorbs phenol from wastewater. [ABSTRACT FROM AUTHOR]

Higher education requires learning in the form of practice and research which is often carried out in the laboratories. The research completed in the laboratory usually produces wastewater which not only has a high organic content, but also contains heavy metal ions, such as copper (Cu), cadmium (Cd), and lead (Pb). These heavy metal ions will harm the environment when directly disposed of without being treated first. One of methods to reduce the level of heavy metal ions in laboratory wastewater is adsorption using chitosan. Therefore, this research was focused on removal heavy metal ions in laboratory wastewater by adsorption method using a chitosan derived from fish scales. The objective of this research was to investigate the effect of pH on the removal of Cu, Cd, and Pb ions in the treatment of synthetic wastewater using chitosan. The effect of chitosan dose on the treatment of laboratory wastewater was also examined. Initially, the chitosan was applied in reducing the metal ions in synthetic wastewater. The synthetic wastewater was prepared using single-component and multi-component samples of heavy metal ions. In this study, the pH was varied from 3–7 for application of chitosan on single and multicomponent synthetic wastewater experiments. Optimum pH was produced and then used to remove the metal ions included in the laboratory wastewater sample. The chitosan dose was varied 0.5–2 g/L. As a result, the highest removal percentage for the reduction of Cu, Cd, and Pb metal ions in single-component synthetic wastewater was at pH 7. However, the highest removal percentage for the reduction of Cu, Cd, and Pb metal ions in multicomponent synthetic wastewater were found in different pH, such as Cu ions at pH 5, Cd ions at pH 7, and Pb ions at pH 3. When applied to laboratory wastewater assessments with pH of 7 and chitosan doses of 0.5–2 g/L, the highest percentage removal of Pb ions (93.75%) was reached when using chitosan dosage of 1.5 g/L; the highest percentage removal of Cu ions (28.99%) was obtained when using chitosan dosage of 2 g/L. Alas, the chitosan dose of 0.5–2 g/L did not have a significant effect on reducing the Cd ions. [ABSTRACT FROM AUTHOR]

Castor oil‐based polyurethane has been researched for its utility in heavy metal adsorption. To improve the adsorptive performance, the polymer can be incorporated with cellulose—a renewable and widely available biopolymer. The aim of this research was to synthesize a film composite prepared from castor oil‐based polyurethane and cellulose for adsorptive removal of aqueous Cd and Pb. One‐shoot synthesis method was employed by mixing cellulose filler with castor oil and toluene diisocyanate (TDI). Characterization was carried out by FT‐IR, SEM, TGA, DSC, and contact angle analyses. Batch adsorption was carried out for the Cd and Pb with variations in contact time and initial pH, before analyzed for the adsorptive performance using 1064 nm Nd:YAG laser spectroscopy. The resulted adsorbents had improved thermal stability, and lower hydrophobicity. Adsorption of Pb and Cd increased 2 and 35 times after the addition of 0.1 g cellulose, respectively. Batch adsorption test revealed that the optimum conditions are 120‐min contact time and pH of 9 and 7 (for Cd and Pb, respectively). In conclusion, incorporation of cellulose could modify the characteristics of castor oil‐based polyurethane film and improve the adsorption of Cd and Pb. [ABSTRACT FROM AUTHOR]

This review paper explores the use of red mud as a sustainable alternative for construction materials and soil stabilisation due to its unique chemical and mineral composition, a waste produced during the extraction of aluminium from bauxite ore. The disposal of red mud is a major environmental issue worldwide due to its high alkalinity and large production volume. Although this material has already been utilised as construction material (e.g., bricks, cement, concrete), it can also be incorporated for waste water treatment and lead to waste reduction. In soil stabilisation, red mud's alkaline nature, pozzolanic properties, and fine particle size improve soil structure and strength, offering a cost-effective solution. Utilising red mud as a filling material for low-lying areas addresses the disposal problem while contributing to infrastructure development projects. This study highlights construction materials' mechanical properties and durability by incorporating bauxite tailings and also incorporating valorisation of red mud as a precursor for alkali-activated binder. This paper comprises recent research findings and practical applications associated with the use of this waste. Also, it discusses the benefits and challenges associated with the large-scale use of red mud. It gives an idea about how the strength and durability of construction materials can be improved considering overall environmental impact. Future perspectives on policy, technology, and environmental impact are also discussed to provide a comprehensive understanding of red mud's potential for sustainable development. Article Highlights: Red mud enhances the properties of materials like strength, durability, and thermal resistance of construction materials like bricks, ceramic, and cement. Red mud increases soil load-bearing capacity, reduces plasticity, and enhances erosion resistance, making it ideal for foundations and road construction. Using red mud reduces dependency on traditional raw materials, conserving natural resources and lowering environmental impacts. Red mud in construction and soil stabilisation contributes to durable, eco-friendly structures and supports sustainable land use. [ABSTRACT FROM AUTHOR]

Introduction: Anaerobic–anoxic–oxic (A2/O) and deoxidation ditch (DOD) processes are being increasingly preferred owing to their effectiveness in treating various wastes in wastewater treatment plants (WWTPs). Considering seasonal variations is crucial in optimizing treatment processes, ensuring compliance with regulations, and maintaining the overall efficiency and effectiveness of WWTPs. This study aimed to determine the influence of seasonality on nitrogen removing microbes and functional genes within A2/O and DOD processes in the humid Wuhan and semi-arid Xi'an cities, China. Methods: The physicochemical parameters of water quality were determined, and molecular and bioinformatic analyses of the bacterial community and nitrogen metabolism functional genes in the two different treatment processes of two WWTPs were performed over four seasons. Results and discussion: Our analyses revealed a significant difference in all physicochemical parameters across all experimental groups (p < 0.05). At the genus level, the abundance of Dokdonella , one unidentified genus of Nitrospiraceae , Terrimonas , and one unidentified genus of Chloroflexi was the highest in all groups. Generally, warmer seasons exhibited higher biodiversity indices. The A2/O system exhibited higher values in terms of most nitrogen metabolism functional genes than those of the DOD sewage treatment system. In both WWTPs, the abundance of most genes in spring and summer were higher than that of autumn and winter seasons. Taken together, changes in temperature, caused by seasonal changes, may contribute to changes in abundance of nitrogen metabolic functional genes. [ABSTRACT FROM AUTHOR]

Using technologies and enforcing national reuse guidelines helps reduce health risks from recycled water used in irrigation. Analysing viral presence in raw and treated sewage is crucial for preventing pandemics. This study used qPCR to evaluate three urban wastewater treatment plants in Ramallah: Al-Tireh MBR, Al-Bireh AS, and Rawabi MBBR. Samples collected in March 2019 were treated and analysed using real-time PCR with specific primers and probes. Results showed Al-Tireh MBR achieved 100% removal of enterovirus, adenovirus, norovirus, and rotavirus. Al-Bireh WWTP achieved 33% removal for adenovirus and rotavirus. Rawabi MBBR achieved varying removal rates: 100% for adenovirus, 33% for norovirus, and 66% for rotavirus. Chlorinated samples showed no direct correlation between faecal coliforms and viral presence. These findings suggest retrofitting Al-Bireh WWTP and Rawabi MBBR with ultrafiltration or MBR units to mitigate viral outbreaks. [ABSTRACT FROM AUTHOR]

Ammonia electrooxidation in aqueous solutions can be a highly energy‐efficient process in producing nitrate and nitrite while generating hydrogen under ambient conditions. However, the kinetics of this reaction are slow and the role of catalyst in facilitating ammonia electrooxidation is not well understood. In this study, a high‐performance NiOOH‐Ni catalyst is introduced for converting ammonia into nitrite with Faraday efficiency of up to 90.4% and nitrate production rate of 1 mg h−1 cm−2. By employing Operando techniques, the role of NiOOH catalyst is elucidated in the dynamic electrooxidation of ammonia. Density functional theory (DFT) calculations support experimental observations and reveal the mechanism of the electrochemical oxidation of ammonia to nitrite and nitrate. Overall, this research contributes to the development of a cost‐effective and highly efficient catalyst for large‐scale ammonia electrolysis, while shedding light on the underlying mechanism of the NiOOH catalyst in ammonia electrooxidation. [ABSTRACT FROM AUTHOR]

This work investigated the photochemical degradation of malachite green (MG), a cationic triphenylmethane dye used as a coloring agent, fungicide, and antiseptic. UV photolysis was ineffective in the removal of MG as only 12.35% degradation of MG (10 mg/L) was achieved after 60 min of irradiation. In contrast, 100.00% degradation of MG (10 mg/L) was observed after 60 min of irradiation in the presence of 10 mM H2O2 by UV/H2O2 at pH 6.0. Similarly, complete removal (100.00%) of MG was observed at 30 min of the reaction time by UV/H2O2/Fe2+ employing [MG]0 = 10 mg/L, [H2O2]0 = 10 mM, [Fe2+]0 = 2.5 mg/L, and [pH]0 = 3.0. For the UV/H2O2 process, the degradation efficiency was higher at pH 6.0 than at pH 3.0 as the k obs values were 0.0873 and 0.0690 min−1, respectively. However, UV/H2O2/Fe2+ showed higher reactivity at pH 3.0 than at pH 6.0. Chloride and nitrate ions slightly inhibited the removal efficiency of MG by both UV/H2O2 and UV/H2O2/Fe2+ processes. Moreover, three degradation products (DPs) of MG, (i) 4-dimethylamino-benzophenone (DABP), (ii) 4-amino-benzophenone (ABP), and (iii) 4-dimethylamino-phenol (DAP), were identified by GC-MS during the UV/H2O2 treatment. These DPs were found to demonstrate higher aquatic toxicity than the parent MG, suggesting that researchers should focus on the removal of target pollutants as well as their DPs. Nevertheless, the results of this study indicate that both UV/H2O2 and UV/H2O2/Fe2+ processes could be implemented to alleviate the harmful environmental impacts of dye and textile industries. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants (WWTPs) receive wastewater from various sources. Despite wastewater treatment aiming to remove contaminants, microplastics persist. Plastic surfaces are quickly colonized by microbial biofilm ("plastispheres"). Plastisphere communities are suggested to promote the spread and survival of potential human pathogens, suggesting that the transfer of plastispheres from wastewater to the environment could pose a risk to human and environmental health. The study aimed to identify pathogens in wastewater plastispheres, specifically food-borne pathogens, in addition to characterizing the taxonomic diversity and composition of the wastewater plastispheres. Plastispheres that accumulated on polypropylene (PP), polyvinyl chloride (PVC), and high-density polyethylene propylene (HDPE) surfaces exposed to raw and treated wastewater were analyzed via cultivation methods, quantitative reverse transcription PCR (RT‒qPCR) and 16S rRNA amplicon sequencing. RT‒qPCR revealed the presence of potential foodborne pathogenic bacteria and viruses, such as Listeria monocytogenes, Escherichia coli, norovirus, and adenovirus. Viable isolates of the emerging pathogenic species Klebsiella pneumoniae and Acinetobacter spp. were identified in the plastispheres from raw and treated wastewater, indicating that potential pathogenic bacteria might survive in the plastispheres during the wastewater treatment. These findings underscore the potential of plastispheres to harbor and disseminate pathogenic species, posing challenges to water reuse initiatives. The taxonomic diversity and composition of the plastispheres, as explored through 16S rRNA amplicon sequencing, were significantly influenced by the wastewater environment and the duration of time the plastic spent in the wastewater. In contrast, the specific plastic material did not influence the bacterial composition, while the bacterial diversity was affected. Without efficient wastewater treatment and proper plastic waste management, wastewater could act as a source of transferring plastic-associated pathogens into the food chain and possibly pose a threat to human health. Continued research and innovation are essential to improve the removal of microplastics and associated pathogenic microorganisms in wastewater. [ABSTRACT FROM AUTHOR]

The rapid growth of the dye industry and the worsening water resource crisis have drawn significant focus to the treatment of dye wastewater. Membrane separation technology is increasingly being utilized in addressing this issue. However, traditional separation membranes face challenges such as susceptibility to contamination and significant decline in subsequent separation permeance. This work utilizes a straightforward brushing technique to effectively apply a coating comprising titanium dioxide (TiO2) nanoparticles and attapulgite (APT) onto a stainless steel mesh (SSM), equipping it with the capability for dye adsorption and separation. Studies show that coatings with different ratios yield varying degrees of coverage on the SSM. A higher concentration of TiO2/attapulgite results in improved coverage on the SSM, creating a denser coating on the mesh surface and the degree of cross-linking of the coating was as high as 92.22%. The coated meshes exhibited superhydrophilicity uniformly and excellent negatively charged properties. Separation experiments of the meshes with different TiO2/attapulgite ratios were conducted by separating simulated dye wastewater with methylene blue (MB) and safranine T (SaT). The results indicate that the prepared meshes achieved a maximum rejection of over 98.0% for MB and over 96.5% for SaT. In addition, the prepared meshes maintained high dye rejection efficiencies (>96%) even after 10 consecutive separation cycles. The above results indicate that the prepared meshes are promising for application in industrial dye wastewater treatment. [ABSTRACT FROM AUTHOR]

A formulated photocurable poly(ethylene glycol) diacrylate (PEGDA) and 2‐hydroxylethyl methacrylate (HEMA) polymer matrix (PEGDA:HEMA) was developed for constructing an adsorptive 3D cubic monolith using masked stereolithography (MSLA) 3D‐printing technique. A pure PEGDA formulation served as a control in comparative studies. Additionally, two structural designs (solid cube and cubic lattice) were also quantitatively compared to determine the adsorption performance for Rhodamine B (RhB) dye removal. Results indicated that the cubic lattice formulated with hydrophilic PEGDA:HEMA (θ~47.20°) was more effective at removing RhB dye. Additionally, the preliminary study identified pH 9 as the optimal level for RhB dye removal using 3D cubic monolith for both formulations. A Taguchi orthogonal array of L9 (33) was used to concurrently vary three parameters: adsorbent dosage (0.65 ± 0.02 g per cubic lattice), operating temperature (30°C, 40°C, and 50°C), and initial RhB concentration (20, 60, and 100 ppm). The highest mean of the signal‐to‐noise (S/N) ratio was chosen to obtain the highest adsorption performance. The removal efficiency (R%) of RhB dye ranged from 44.48% to 94.86%, and the adsorption capacity (K) ranged from 0.59 to 3.73 (mg/g) after 5 h. Seven adsorption isotherms and five adsorption kinetics modelling were performed. Adsorption isotherm data fitted well with the Redlich–Peterson model for both linear (R2 = 0.998) and nonlinear (R2 = 1). Besides that, the pseudo‐second‐order model (PSO) accurately described adsorption kinetics (R2 = 0.995). The separation factor (RL) confirmed favourable adsorption (0 < RL < 1). Thermodynamic parameters indicated that the adsorption process was endothermic and at higher temperatures, entropy increased. Also, the 3D–printed PEGDA:HEMA cubic lattice exhibited good mechanical stability. Furthermore, the 3D PEGA: HEMA lattice has the ability to be used in several adsorption cycles of degrading RhB dye. Ultimately, the present work demonstrates the viability of 3D printing photocurable PEGDA:HEMA resin and utilizes statistical tools to optimize process parameters, enhancing predictability for wastewater management. [ABSTRACT FROM AUTHOR]

The transition from traditional wastewater treatment plants to biorefineries represents an environmentally and economically sustainable approach to extracting valuable compounds from waste. Sewage sludge produced from wastewater treatment is incinerated or disposed of in specific landfills. Repurposing this waste material to recover valuable resources could help lower disposal costs and reduce environmental impact by producing other beneficial polymers. Microorganisms present in the sewage sludge can ferment organic pollutants, producing volatile fatty acids (VFA), precursors for biopolymers that could be used as an alternative to petroleum-derived plastics. To boost VFA production during sewage sludge fermentation, it is necessary to understand the operating microbial community and its metabolic capacities in anaerobic conditions. This study presents the influence of the headspace volume on the microbial community and the VFA production to define the best operational parameters in a 225 L pilot plant fermenter. The wasted sewage sludge was withdrawn from an oxic-settling-anaerobic plant that collected wastewater from the canteen and dormitory of the UNIPA Campus (Palermo University, Italy) and incubated using a 40% and a 60% headspace volume. The microbial community was analysed before and after the fermentation process through metataxonomic analysis, and VFA yields were determined by gas chromatography analysis. Our results showed that the 40% headspace volume induced a tenfold higher VFA production than the 60% headspace volume, modulating the microbial community's efforts to establish a VFA-producing factory. Notably, at 40% headspace, the relative abundance of bacteria, like Proteobacteria, Firmicutes, Actinobacteria, and Chloroflexi, significantly increased, as well as the relative abundance of Bacteroidetes and Verrucomicrobia decreased during the fermentation process. This result is consistent with the selection of efficient VFA-producing bacteria that lead to increased VFA yields that are not obtained at 60% headspace. Thus, reducing headspace is a promising strategy that can be implemented, even in full-scale plants, to optimise the wastewater reuse process and maximise VFA production to produce bioplastics, like polyhydroxyalkanoate, for the transition from linear wastewater treatment plants to circular biorefineries. [ABSTRACT FROM AUTHOR]

Hexavalent chromium (Cr(VI)) contamination in drinking water due to industrial activities is a growing worldwide concern. Cr(VI) concentrations exceeding a few parts per billion (ppb) can cause serious health problems such as asthma, blood cancer, kidney-related diseases, liver and spleen damage, as well as neurological system, immunological deficiencies, and reproductive issues. This study, thus, explored the feasibility of employing a novel polymeric ferromagnetic nanocomposite adsorbent made of low-cost, biodegradable, and ultra-permeable materials from pulp and paper sludge for adsorptive removal of hexavalent chromium (Cr6+) from synthetic wastewater. Vibrating-sample magnetometer (VSM), X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmet-Teller surface area (BET), and Fourier transform infrared (FTIR) were used to analyze the produced nanocomposite adsorbent. The Fourier transform infrared results confirmed the presence of adsorptive peaks attributed to −OH, −NH2, and FeO. Scanning electron microscopy micrographs revealed a porous adsorbent surface. XRD revealed the existence of the crystalline spinel-structured magnetite (Fe3O4) phase of iron oxide, while the saturation magnetization was established to be 26.90 emu/g. The Brunauer–Emmett–Teller analysis confirmed a slight decrease in the surface area of the nanocomposite adsorbent to 6.693 m2.g−1, compared to Fe3O4 (7.591 m2.g−1). The optimum conditions for Cr6+ removal were pH 2.0, 1.0 g/L adsorbent dose, room temperature (25°C), 120 min contact time, and 20 mg/L pollutant concentration. During removal, the Cr(VI) was adsorbed by electrostatic attraction and/or reduced to trivalent chromium Cr(III). At low starting Cr(VI) concentrations, chemisorption dominated the removal process, but as concentrations increased, physisorption became more significant. The prepared nanocomposite adsorbent presented exceptional removal efficiency of up to 92.23%, indicating that it may be useful for the adsorption of metal ions from industrial and household wastewater. [ABSTRACT FROM AUTHOR]

AbstractHexavalent Chromium (Cr(VI)) is essential in many industrial processes. However, it finds its way into water bodies, posing health problems, including lung cancer and the inhibition of DNA and RNA in biological systems. Several chemical and traditional water purification methods have been developed in the past, but most are expensive, tedious and ineffective. This study aimed to prepare and characterize a low-cost hybrid adsorbent, β-Cyclodextrin capped magnetic nanoparticles anchored on a cellulosic matrix (CNC-Fe3O4NP-CD). The characterization techniques confirmed the integration of CNCs, Fe3O4NP and CD into the prepared CNC-Fe3O4NP-CD nanocomposite adsorbent. The adsorbent was employed in batch adsorption experiments by varying adsorption parameters, including solution pH, adsorbent dosage, initial Cr(VI) concentration, and contact time. From the findings, the nanocomposite adsorbent achieved a maximum Cr(VI) removal efficiency of 97.45%, while the pseudo-second-order kinetic model best fitted the experimental data with high linear regression coefficients (R2 > 0.98). The Elovich model indicated that the adsorption process was driven by chemisorption on heterogeneous surface sites, with initial sorption rates surpassing desorption rates. These findings established that CNC-Fe3O4NP-CD presents high efficiency for Cr(VI) removal under acidic pH, offering the potential for optimization and application in real-world wastewater treatment. [ABSTRACT FROM AUTHOR]

The past decades have seen considerable imbalances in the nitrogen cycle due to the excessive use of nitrate in agriculture and industry. Electrocatalytic reduction of nitrate (NO3RR) to nitrogen (N2) holds significant potential for addressing nitrate pollution in wastewater but suffers from nitrite formation and the sluggish hydrogeneration process. Here a single atom alloy (SAA) catalyst featuring atomically dispersed Ru on 2D Ni metal (Ru1Ni), proving remarkable nitrate reduction performance (NO3−–N conversion (≈93%) and N2 selectivity (≈99%)) through the co‐catalytic metal‐support interactions (CMSI) effect is reported. Significantly, the Ru1Ni SAA achieves NO3RR removal capacity as high as 11.1 mg L−1 h−1 cm−2 with 20 cycles stability (9 h per cycle), surpassing most previously reported works. The core of the boosting lies in the synergistically promoted nitrate activation and accelerated hydrogenation of nitrogen oxide intermediates on the Ru site and Ni substrate, respectively, revealed by various in situ experiments and theoretical simulations. DFT calculations indicate electron transfer from substrate Ni to Ru and more robust interaction between NO3− and Ru–Ni in comparison to that of Ni–Ni. This work offers a resilient methodology for the rational design of highly efficient electrocatalysts with CMSI modulation for NO3RR, illuminating the arena of wastewater treatment and the nitrogen cycle. [ABSTRACT FROM AUTHOR]

Dye wastewater is becoming one of the most significant sources of water pollution, and its impact on human survival is immeasurable. In this study, we successfully synthesized a nanofiber membrane with environmentally friendly and efficient properties using electrospinning of a mixture of sodium alginate (SA) and copper oxide (CuO) nanoparticles, aimed at effective dye removal. The adsorption performance of the SA/CuO nanofiber membrane was evaluated using the cationic dye methylene blue (MB). The maximum adsorption capacity of the nanofiber membrane was increased significantly with the addition of CuO nanoparticles, reaching a maximum value of 1633.4 mg g−1, almost twice as much as that of pure SA membrane. The adsorption kinetics follows the pseudo‐second‐order model, where chemisorption acts as the rate‐limiting step. The adsorption isotherm data indicate that the adsorption is monolayer. The nanofibrous membranes showed better dye removal under an alkaline environment. After four cycles of adsorption/desorption, the MB removal efficiency remained at 70.1% of the original adsorption capacity. The addition of CuO nanoparticles facilitated the adsorption of MB dyes, while the form of the nanofibrous membrane is easily recoverable and reusable. Therefore, the as‐prepared SA/CuO nanofibrous composite membrane is a potentially favorable adsorbent material for wastewater treatment applications. [ABSTRACT FROM AUTHOR]

To remove heavy metals from wastewater, coal gasification slag (CGS) was prepared as an adsorbent. Five modified materials were created, including HF‐CGSC, KOH‐HCl‐CGS, and three KOH‐CGS variants with different mass ratios. The adsorption tests showed KOH‐CGS (0.25) had the best efficiency for Pb(II) and Cd(II) via spontaneous chemisorption. Kinetic, thermodynamic, and 13C NMR analyses indicated that adsorption involved pore adsorption, functional group coordination, and π‐π interactions. Competitive adsorption results showed minimal interaction between Pb and Cd. Leaching tests confirmed the process's environmental safety. This study suggests new approaches for using coal gasification slag in wastewater treatment. [ABSTRACT FROM AUTHOR]

Critical water crisis due to overpopulation, industrialization and urbanization has resulted to the shortfall of providing safe drinking water to one billion people in the world. This work intends to fabricate modified hydrophobic polyvinylidene fluoride (PVDF) membrane by hydrophilic chitosan extracted from waste fish scales for wastewater treatment. Chitosan was blended with PVDF in N-methyl-2-pyrrolidone solution by solution casting method. Three different concentrations of 1, 3 and 5 wt% of chitosan were taken. The morphological, spectral and thermal analysis of the produced films were elaborately studied. The contact angle decreased with the increase of chitosan content from 82.64° to 60.97°. The tensile strength decreases from 1.11 to 0.38 MPa and Young’s modulus decreased from 12.08 to 7.4 MPa with increase in chitosan content in the film from 1 to 3 %. The performance of microparticle embedded membrane was compared with the pristine PVDF membrane, and it was affirmed that the microsized-chitosan embedded PVDF membrane manifests a broad promising application perspective towards wastewater treatment owing to its excellent water flux (76 L m−2 h−1) as well as antibacterial properties. [ABSTRACT FROM AUTHOR]

This paper presented an addendum rotational hydrodynamic cavitation reactors (ARHCR) that enabled circumferential shear cavitation, axial cavitation, and the Venturi effect, thus increasing cavitation efficiency. The experiments on hydroxyl (·OH) release and chemical oxygen demand (COD) removal demonstrate the feasibility of cavitation performance characterization and COD removal rate. The findings indicate that the COD removal rate can reach a maximum value of 28% or 30% with an increase in flow rate or rotating speed, respectively. Specifically, the maximum values were achieved at a rotation speed of 2,500 rpm or a flow rate of 1.0 m3·h−1. Based on the mechanism of the addendum cavitation, the wedge angles, and the crucial structural parameters, were examined for optimizing cavitation performance. The results revealed that the cavitation number and cavitation bubble were significantly influenced by wedge angles, as well as the efficiency of cavitation energy. The mechanical shear of fluid was enhanced by wedge angles, resulting in constant compression and release of fluid with increased kinetic energy. This led to stronger effects on bulge blocks, and the formation of vortexes that rebounded constantly, resulting in lower pressure areas and expanded regions of cavitation. Among the wedge angles tested, the wedge angle of 15° exhibited the highest cavitation bubbles with a maximum value of 46%. This was 31% higher than the grooves‐type cavitator reported. Furthermore, the cavitation performance was extremely improved with a wedge angle of 15°, as corresponding with the maximum efficiency of cavitation energy. These explorations provide references for the removal of COD in industrial and agricultural wastewater, as well as the development of novel reactors for wastewater treatment. [ABSTRACT FROM AUTHOR]

The use of a photo-electrochemical cell (PEC) to produce hydrogen from wastewater is a promising innovation. In this context, this study investigates the impact of a pollutant on the photo-electrochemical properties of sol-gel synthesized TiO 2 and TiO 2 –Co 3 O 4 thin films for hydrogen production in a polluted electrolyte. Combining the photocatalytic properties of TiO 2 with the electronic properties of Co 3 O 4 offers an effective solution for achieving effective photo-electrochemical properties in polluted environments. Nevertheless, despite the lowest photocatalytic activity, the hybrid thin film TiO 2 –Co 3 O 4 with the highest Ti/Co ratio (1:0.5) shows the most promising performance with simultaneous 11.4 μmol cm−2 h−1 H 2 production and 12% acid orange 7 degradation after 3 h irradiation under xenon light without the use of any sacrificial agent. This indicates that the electronic conductivity provided by the presence of Co 3 O 4 is a critical property for achieving optimal performance in PEC coupling for hydrogen production and wastewater treatment. [Display omitted] • Sol-gel TiO 2 –Co 3 O 4 films enabled coupling of water splitting and remediation. • 11 μmol cm−2 h−1 H 2 was produced after 3h Xe irradiation without sacrificial agent. • Simultaneous 12% acid orange 7 degradation was measured. [ABSTRACT FROM AUTHOR]

The generation of hydrogen fuel, and wastewater treatment according to solar-driven catalysis possesses considerable prospective for establishing a carbon-neutral and ecologically sound power infrastructure. Driven by this problem, we suggest in this study, adopting a simple impregnation method, a customized association of CoAl-LDH and graphitic carbon nitride (CN), a visible light active narrow and wide band gap semiconductors. Several characterization approaches were implemented to understand the CoAl-LDH@g-C 3 N 4 (CACN) composites' physiochemical and optical features. The CACN hetero structural forms exhibited significantly improved solar light-induced photocatalytic H 2 generation and dye pollutants decomposition in contrast with pristine materials. The most effective catalyst 5 wt% CoAl-LDH@g-C 3 N 4 (5-CACN) generated the highest hydrogen (∼430.7 μmolg−1h−1), which is 11.9-fold H 2 production efficiency compared with CN and depicted significant Brilliant black dye removal efficacy via photocatalytic degradation (up to ∼79%). This was primarily ascribed to the development of the Type-II CACN heterojunctions, which promoted the separation of charges and expanded the abundance of surface-active sites while absorbing the visible spectrum of solar light. To examine the photocatalytic proficiency for H 2 production and dye pollutant removal over CoAl-LDH@g-C 3 N 4 heterojunction nanocomposites synthesized via a facile impregnation approach and plausible schematic photocatalytic mechanism for H 2 production and Brilliant black dye pollutant removal under visible photons illumination. [Display omitted] • A facile single-step hydrothermal method was employed to synthesize the CoAl-LDH nanotextures. • Type-II heterojunction CoAl-LDH@g-C 3 N 4 composites were prepared via a simple impregnation approach. • Type-II heterojunction CoAl-LDH@g-C 3 N 4 composites display an enhanced H 2 production during sunlight illumination. • Type-II heterojunction CoAl-LDH@g-C 3 N 4 depicts a significantly superior photocatalytic degradation of Brilliant Black dye in a water sample. • Plausible mechanism of Type-II heterojunction CoAl-LDH@g-C 3 N 4 for H 2 production and photocatalytic degradation of Brilliant Black dye. [ABSTRACT FROM AUTHOR]

In recent years, reducing the concentration of carbon dioxide in the atmosphere has become an important issue. Microalgae have a higher photosynthetic efficiency and growth rate than higher plants; thus, biological carbon dioxide fixation using microalgae is attracting particular attention as an efficient carbon dioxide fixation method. However, under dilute atmospheric conditions, microalgae exhibit lower growth rates and reduced carbon dioxide fixation efficiency. In recent years, technology that can efficiently fix carbon dioxide, even in the atmosphere, using a microalgae co-culture system that co-cultivates microalgae and heterotrophic microorganisms has attracted attention. In such a co-culture system, it is believed that a mutualistic relationship is established between microorganisms through the exchange of various compounds. This review focuses on the application of a co-culture system of microalgae and heterotrophic microorganisms for bioproduction and wastewater treatment. In addition, research to elucidate the mutualistic relationships in microalgal co-culture systems using analytical methods that have been widely used in recent years, such as next-generation sequencing technology, is also discussed. In the future, it is expected that the use of microalgae co-culture systems will expand on an industrial scale through the development of key technologies, such as efficient genetic modification techniques for microalgae and their heterotrophic microorganism partners, large-scale cultivation facilities that can efficiently cultivate microalgae, and stable control techniques for co-culture systems using advanced technology. [ABSTRACT FROM AUTHOR]

The search for low-cost and effective adsorbents for the removal of organic dyes from contaminated water is urgently needed. The substantial amount of waste mushroom cultivation substrates generated in practical production can serve as an ideal material for the preparation of adsorbents. In this study, we investigated the main control parameters affecting the performance of magnetic mushroom substrate biochar and optimized the process of preparing biochar by using the Plackett–Burman and central composite design methods. Various analytical techniques including SEM, EDX, BET, and VSM were used to characterize the biochar. The results indicate that the carbonization temperature had the most significant impact on the yield and adsorption performance of biochar. Under the conditions of a carbonization temperature of 600 °C, a carbonization retention time of 1 h, and an impregnation ratio of 0.1, the yield and methylene blue adsorption value of magnetic biochar were 42.54% and 2297.04 μg/g, respectively, with a specific surface area of 37.17 m2/g. This biochar effectively removed methylene blue from the solution, demonstrating a high economic efficiency for wastewater treatment and pollution control. Furthermore, the adsorption–desorption cycle studies revealed its excellent stability and reusability. Additionally, based on the response surface methodology, a three-dimensional surface model of the adsorption performance of magnetic biochar under different carbonization conditions was established, providing a theoretical basis for the preparation of magnetic biochar from agricultural wastes. [ABSTRACT FROM AUTHOR]

Ion-adsorbing rare earth tailings (IRETs) contain a large amount of clay minerals, which are a potential source of silicon and aluminum for the preparation of zeolite materials. The complexity of the tailings' composition and the impurity composition are the main difficulties in the controllable preparation of zeolite. Herein, IRETs were treated by classification activation technology for the preparation of IRET-ZEO, which was used for the removal of heavy metal Pb2+ in water. A new method of resource utilization of ion-type rare earth tailings is realized by "treating waste with waste". The results showed that the IRETs were classified and then thermally activated, and the optimal activation parameter was calcination at 850 °C for 1 h. The optimal NaOH concentration used in the crystallization process was 5 mol/L, with a crystallization time of 3 h and a crystallization temperature of 85 °C, and the crystallization product was zeolite A. The removal rate of the Pb2+ solution with an initial concentration of 100 mg/L was as high as 96.7% in an acidic solution with a pH value from 2 to 5.5. In particular, when the solution pH was higher than 4.2, the adsorption rate of Pb2+ was close to 100%. The IRET-ZEO showed a fast adsorption rate (5 min to reach adsorption equilibrium), a large adsorption capacity (378.35 mg/g), excellent acid resistance, and selectivity and regenerability for Pb2+. This work provides a new strategy for the green resource utilization of IRETs and the treatment of lead-containing wastewater. [ABSTRACT FROM AUTHOR]

Bubble coalescence plays a critical role in optimizing biological and industrial processes, impacting efficiency in areas such as fermentation, wastewater treatment, and foaming control. While the relationship between chemical structure and bubble coalescence has been thoroughly explored for inorganic ions, limited data exist on organic ions and surfactants, despite their widespread use in these industries. This study addresses this gap by investigating the effects of surfactant hydrophobicity and bubble size on coalescence behavior at a flat air–liquid interface and within a bubble column. Surface tension measurements were employed to assess surfactant hydrophobicity, while bubble size and coalescence time were analyzed to determine their respective influences. The results reveal a novel quantitative relationship between surfactant hydrophobicity and the half-coalescence inhibition concentration (HCIC), a new variable introduced in this study. This relationship demonstrates that as hydrophobicity increases, the HCIC also rises, providing a new relationship between surfactant hydrophobicity and bubble coalescence. While it is well-known that more hydrophobic molecules delay coalescence, this is the first time a direct, proportional relationship has been established with HCIC, offering a new parameter for predicting and controlling coalescence phenomena. [ABSTRACT FROM AUTHOR]

Ensuring clean water sources is pivotal for sustainable development and the well-being of communities worldwide. This study represents a pioneering effort in water purification, exploring an innovative approach utilizing modified reduced graphene oxide (rGO) aerogels. These advanced materials promise to revolutionize environmental remediation efforts, specifically removing organic contaminants from aqueous solutions. The study investigates the exceptional adsorption properties of rGO-aerogel, enhanced with cysteamine, to understand its efficacy in addressing water pollution challenges. The characterization methods utilized encompass various analytical techniques, including FE-SEM, BET, FTIR, TGA, DSC, XPS, NMR, and elemental analysis. These analyses provide valuable insights into the material's structural modifications and surface chemistry. The research comprehensively explores the intricacies of adsorption kinetics, equilibrium, and isothermal study to unravel the underlying mechanisms governing contaminant removal. MO and Ni2+ exhibited adsorption of 542.6 and 150.6 mg g−1, respectively, at 25 °C. Ni2+ has unveiled the highest removal at pH 5, and MO has shown high removal in a wide pH range (pH 4–7). Both contaminants have shown fast adsorption kinetic performance on an rGO-aerogel surface. This study aims to identify the synergistic effect of cysteamine and rGO in aerogel formation to remove heavy metals and organic contaminants. These findings mark a significant stride in advancing sustainable water-treatment methods and pioneering in synthesizing innovative materials with versatile applications in environmental contexts, offering a potential solution to the global water pollution crisis. [ABSTRACT FROM AUTHOR]

Effective wastewater treatment remains a critical challenge, especially when dealing with hazardous pollutants like antimony (Sb(III)). This study addresses this issue by using innovative nanocomposites to remove Sb(III) ions from water, while simultaneously repurposing the spent adsorbents for energy storage applications. We developed reduced graphene oxide-NiFe2O3-SiO2-polyindole nanocomposites (RGO-NiFe2O3-SiO2-PIn NCs) via a hydrothermal synthesis method, achieving a high removal efficiency of 91.84% for Sb(III) ions at an initial concentration of 50 mg/L at pH 8. After adsorption, the exhausted adsorbent was repurposed for energy storage, effectively minimizing secondary pollution. The Sb(III)-loaded adsorbent (RGO-NiFe2O3-SiO2-PIn@SbOx) exhibited excellent performance as an energy storage material, with a specific capacitance (Cs) of 701.36 F/g at a current density of 2 A/g and a retention rate of 80.15% after 10,000 cycles. This dual-purpose approach not only advances wastewater treatment technologies but also contributes to sustainable and economical recycling practices, particularly in the field of energy storage. [ABSTRACT FROM AUTHOR]

Currently, industrial water pollution represents a significant global challenge, with the potential to adversely impact human health and the integrity of ecosystems. The continuous increase in global consumption has resulted in an exponential rise in the use of dyes, which have become one of the major water pollutants, causing significant environmental impacts. In order to address these concerns, a number of wastewater treatment methods have been developed, with a particular focus on physicochemical approaches, such as adsorption. The objective of this study is to investigate the potential of a bio-based material derived from olive oil pomace (OOP) as an environmentally friendly bio-adsorbent for the removal of methylene blue (MB), a cationic dye commonly found in textile effluents. The biobased material was initially characterized by determining the point of zero charge (pHpzc) and using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Subsequently, a comprehensive analysis was conducted, evaluating the impact of specific physicochemical parameters on MB adsorption, which included a thorough examination of the kinetic and thermodynamic aspects. The adsorption process was characterized using Langmuir, Freundlich, Brunauer-Emmett-Teller (BET), and Dubinin Radushkevich (D-R) isotherms. The results suggest that the equilibrium of adsorption is achieved within ca. 200 min, following pseudo-second-order kinetics. The optimal conditions, including adsorbent mass, temperature, bulk pH, and dye concentration, yielded a maximum adsorption capacity of ca. 93% (i.e., 428 mg g−1) for a pomace concentration of 450 mg L−1. The results suggest a monolayer adsorption process with preferential electrostatic interactions between the dye and the pomace adsorbent. This is supported by the application of Langmuir, BET, Freundlich, and D-R isotherm models. The thermodynamic analysis indicates that the adsorption process is spontaneous and exothermic. This work presents a sustainable solution for mitigating MB contamination in wastewater streams while simultaneously valorizing OOP, an agricultural by-product that presents risks to human health and the environment. In conclusion, this approach offers an innovative ecological alternative to synthetic adsorbents. [ABSTRACT FROM AUTHOR]

Weak polyelectrolyte chains are versatile polymeric materials due to the large number of functional groups that can be used in different environmental applications. Herein, one weak polycation (polyethyleneimine, PEI) and two polyanions (poly(acrylic acid), PAA, and poly(sodium methacrylate), PMAA) were directly deposited through precipitation of an inter-polyelectrolyte coacervate onto the silica surface (IS), followed by glutaraldehyde (GA) crosslinking and extraction of polyanions chains. Four core–shell composites based on silica were synthesized and tested for adsorption of lead (Pb2+) and nickel (Ni2+) as model pollutants in batch sorption experiments on the laboratory scale. The sorbed/desorbed amounts depended on the crosslinking degree of the composite shell, as well as on the type of anionic polyelectrolyte. After multiple loading/release cycles of the heavy metal ions, the maximum sorption capacities were situated between 5–10 mg Pb2+/g composite and 1–6 mg Ni2+/g composite. The strong crosslinked composites (r = 1.0) exhibited higher amounts of heavy metal ions (Me2+) sorbed than the less crosslinked ones, with less PEI on the surface but with more flexible chains being more efficient than more PEI with less flexible chains. Core–shell composites based on silica and weak polyelectrolytes could act as sorbent materials, which may be used in water or wastewater treatment. [ABSTRACT FROM AUTHOR]