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Graphene oxide–cobalt ferrite magnetic nanocomposite (M-GOC) was efficiently synthesised by microwave-assisted method for water remediation. The graphene oxide (GO) was synthesized by improved Hummers’ method, while cobalt ferrite (CoFe2O4) was synthesized by microwave-assisted combustion method. X-ray diffractograms indicated high phase-pure M-GOC with an average crystallite size of 18.5 nm. An enhancement in the absorbance was observed in the range of 220–280 nm due to the presence of additional π–π* transition of aromatic C–C bonds of GO. Appearance of a peak around 584 cm−1 corresponds to the stretching vibration of Co–O bond. Corrugated GO sheets were observed in SEM and HRTEM images with agglomerated spherical CoFe2O4 nanoparticles intercalated between the GO sheets. A particle size distribution curve was plotted that indicated an average particle size of ~11 nm of the CoFe2O4 nanoparticles. Raman spectra of GO confirmed the synthesis of pure GO sheets. Vibrating sample magnetometer was employed to investigate the magnetic behaviour of M-GOC, which showed a Mr/Ms ratio of 0.278. The adsorption study was performed, in which M-GOC nanocomposite exhibited an excellent adsorption capacity of 2229.9 mg g−1 for heavy metal i.e., cadmium ions (Cd+2). [ABSTRACT FROM AUTHOR]

Herbicide contamination in aquatic systems has become a global concern due to their long- term persistence, accumulation and health risks to humans. Paraquat, a widely used and cost-effective nonselective herbicide, is frequently applied in agricultural fields for pest control. Consequently, the removal of paraquat from contaminated water is crucial. This research presents a sustainable and environmentally benign method for paraquat removal from aqueous system by integrating wetland plants (Eichhornia crassipes) with biochar derived from melamine-modified palm kernel shells. The prepared biochar was characterized by using various analytical techniques. The effectiveness of biochar in enhancing phytoremediation was evaluated through a series of experiments, showing significant paraquat removal efficiencies of 99.7, 98.3, and 82.8% at different paraquat concentrations 50, 100, and 150 mg L−1, respectively. Additionally, present study examined the impact of biochar on the growth of E. crassipes, highlighting its potential to reduce the toxic effects of paraquat even present at higher concentrations. The paraquat removal mechanism was elucidated, focusing on the synergistic role of biochar adsorption and phytoremediation capability of E. crassipes. This innovative approach is an effective, feasible, sustainable and eco-friendly technique that can contribute to the development of advanced and affordable water remediation processes for widespread application. NOVELTY STATEMENT: The novelty of this study lies in the implementation of combined approach by phytoremediation with biochar modified with melamine. This study highlighted synergistic integration of two concurrent systems. The biochar generated from waste palm kernel shells played a pivotal role in facilitating the plants' survival and resilience against the paraquat toxicity, rather than succumbing to its deleterious effects. This research delineates a robust methodology for the elimination of emerging pollutants, offering researchers a platform to make pioneering advancements in this scientific field for sustainable future. [ABSTRACT FROM AUTHOR]

The present work intended to produce new cost-effective alkali-activated adsorbents from chestnut shells with the purpose of removing fluoride from water, and to explore the effect of pyrolysis temperature on fluoride decontamination at different operational and environmental parameters. The microstructure and morphological characteristics of the resulting activated carbons were thoroughly investigated using BET, FTIR, XRD and SEM. The effectiveness of the prepared adsorbent materials in treating and remediating fluorinated water was evaluated. The impacts of several factors, including the dose of the adsorbent, the initial contamination level of fluoride, and pH on the fluoride removal efficiency were investigated. In accordance with the data, the highest adsorption was found to be at a 6 pH during 5 hours of processing duration and 0.5 g/L of dosage of adsorbent. The experimental results were well-fit by the Freundlich isotherm model and the pseudo-second-order kinetic model. The highest fluoride removal efficiency was found to be 78% at adsorption medium pH 6 and initial fluoride concentration of 10 mg/L by the adsorbent prepared at 800°C. Additional research on adsorption along with rejuvenation revealed that the reduction in adsorption potential to 10% following four repetitions of operation involving regeneration, thereby showcasing the adsorbent's versatile applicability for repeated use. [ABSTRACT FROM AUTHOR]

The hybrid material created by combining cellulose and MOF is highly promising and possesses a wide range of useful properties. Cellulose-based metal–organic frameworks (CelloMOFs) combine the inherent biocompatibility and sustainability of cellulose with the tunable porosity and diverse metal coordination chemistry of MOFs. Cellulose-MOF hybrids have countless applications in various fields, such as energy storage, water treatment, air filtration, gas adsorption, catalysis, and biomedicine. They are particularly remarkable as adsorbents that can eliminate pollutants from wastewater, including metals, oils, dyes, antibiotics, and drugs, and act as catalysts for oxidation and reduction reactions. Furthermore, they are highly efficient air filters, able to remove carbon dioxide, particulate matter, and volatile organic compounds. When it comes to energy storage, these hybrids have demonstrated exceptional results. They are also highly versatile in the realm of biomedicine, with applications such as antibacterial and drug delivery. This article provides an in-depth look at the fabrication methods, advanced applications of cellulose-MOF hybrids, and existing and future challenges. [ABSTRACT FROM AUTHOR]

In the present study, rice straw‐derived cellulose was converted into carboxymethylcellulose (CMC) using alkalization followed by an etherification reaction. The synthesis conditions for this chemical modification were optimized such that CMC with a high degree of substitution (1.02) was obtained. Infrared spectra of the synthesized CMC clearly showed an increased intensity of the C═O bond at 1600 cm−1, confirming successful carboxymethylation. Further, X‐ray diffraction analysis demonstrated a decrease in cellulose crystallinity owing to partial rearrangement from a crystalline to an amorphous phase during initial alkalization reaction. The obtained CMC biopolymer was subsequently cross‐linked to form a composite hydrogel matrix reinforced with bentonite clay. The hydrogel showed about 91% adsorption capacity for methylene blue dye as a model contaminant in aqueous media. Therefore, this study shows that lignocellulosic agrowaste is a rich source of cellulose, and its derivatives such as CMC possess the potential to realize the waste to wealth sustainability goal. [ABSTRACT FROM AUTHOR]

Polymers derived from renewable carbon feedstock are destined to play a pivotal role in the transition to a sustainable circular economy, displacing conventional fossil‐carbon materials. Chitin (CT) and chitosan (CS) are well‐suited to develop multifunctional materials that are mechanically resilient and easy to process. Their abundance of hydroxyl and amine groups facilitates hydrogen bonding and electrostatic interactions, making them suitable for persistent pollutant removal from drinking water. Therefore, porous CS cryogels are fabricated by dissolution in acetic acid, coagulation, and subsequent freeze‐drying. To enhance durability in harsh environments, CT cryogels are obtained through acetylation. Furthermore, Fe3O4 nanoparticles are incorporated to enable removal by external magnetic fields. The rapid removal of per‐ and polyfluoroalkyl substances (PFASs) with capacities reaching 451 mg g−1 offers competitive performance against state‐of‐the‐art materials. The shear‐thinning properties of CS enable rapid additive manufacturing in predetermined free‐standing shapes, useful for accessing sites with complex geometries. Life cycle assessment (LCA) confirms the suitability of chitosan and CT cryogels for low environmental impact water remediation applications. Furthermore, the cryogels can be recycled, closing the material loops back into the economic cycle. Altogether, this work demonstrates the potential of chitosan and CT as competitive alternatives to fossil‐carbon derived systems for sustainable environmental remediation. [ABSTRACT FROM AUTHOR]

In terms of environmental pollution, water pollution is the most significant problem facing living organisms worldwide. Pollutants of various types, including toxic, inorganic, and organic materials, have a detrimental impact on terrestrial and aquatic ecosystems. Materials with layers, such as layered double hydroxides (LDHs), a type of synthetic anion clay, have a wide range of potential applications. In this comprehensive study, we have discussed variety of LDHs, and their explicit properties which have significant advantages for the removal of a variety of pollutants from water. Besides these, LDHs are easily synthesized with high yield and, tuneable structure based on choice of metals, etc. Based on these unique potentials, we have summarized how layered double hydroxides and their hybrids are synthesized efficiently. The performance and applications in removing water pollutants involving heavy metals, inorganic anions, and organics at different parameters such as temperature, adsorbent dosage, pH, and contact time are discussed. Consolidated information has been provided regarding the LDH synthesis, conditions for adsorption, and reference of the particular work. The worked‐up LDH's regeneration potential and methods evolved for regenerating it, different kinetic models and isotherms are also discussed. [ABSTRACT FROM AUTHOR]

The lasting impact of ancestral energy production operations and global manufacturing has not only generated substantial CO2 emissions, but it has also led to the release of metal-based pollutants into Earth's water bodies. As we continue to engineer, mine (coal and metals), and now bore into geothermal wells/fracking sites for alternative energy sources, we continue to contaminate drinking water supplies with heavy metals through infiltration and diffusion, limiting progress towards achieving Sustainable Development Goals 3 (Sustainable Development Goal 3: Good health and well-being), 6 (Sustainable Development Goal 6: Clean water and sanitation), 14 (Sustainable Development Goal 14: Life below water), and 15 (Sustainable Development Goal 15: Life on land). This review shows how the research community has designed and developed mesoporous biochars with customizable pore systems, as well as functionalized biochars, to extract various heavy metals from water sources. This article investigates how biochar materials (non-activated, activated, functionalized, or hybrid structures) can be adapted to suit their purpose, highlighting their recyclability/regeneration and performance when remediating metal-based pollution in place of conventional activated carbons. By utilizing the wider circular economy, "waste-derived" carbonaceous materials will play a pivotal role in water purification for both the developed/developing world, where mining and heavy manufacturing generate the most substantial contribution to water pollution. This review encompasses a wide range of global activities that generate increased heavy metal contamination to water supplies, as well as elucidates emerging technologies that can augment environmental remediation activities, improving the quality of life and standard of living for all. [ABSTRACT FROM AUTHOR]

Amine-functionalized graphene oxide (GO-NH2) was prepared by synthesizing graphene oxide (GO) using the Hummer's method, followed by reacting with (3-aminopropyl)triethoxysilane (APTES). The obtained GO-NH2 was utilized for immobilizing and stabilizing Rh(0) nanoparticles (NPs) to create Rh@GO-NH2 material. The synthesized Rh@GO-NH2 material was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), elemental mapping, and X-ray photoelectron spectroscopy (XPS) analysis. The results indicated that the Rh(0) NPs were successfully decorated on the GO-NH2 surface. The catalytic activity of Rh@GO-NH2 was examined for the hydrogenation of nitroaromatic compounds using NaBH4 as a reducing agent. Results demonstrated that Rh@GO-NH2 effectively catalyzed the hydrogenation of nitroaromatics into the corresponding aniline derivatives in aqueous media at a moderate temperature. Nitroaromatic compounds are considered high toxic water contaminants. The simple preparation of the catalyst, low catalyst loading, and the recoverability of the catalyst are some advantages of this work. [ABSTRACT FROM AUTHOR]

Methylene blue (MB) is a dye hazardous pollutant widely used in several industrial processes that represents a relevant source of water pollution. Thus, the research of new systems to avoid their environmental dispersion represents an important goal. In this work, an efficient and sustainable nanocomposite material based on green gold nanoparticles for MB water remediation was developed. Starting from the reducing and stabilizing properties of some compounds naturally present in Lambrusco winery waste (grape marc) extracts, green gold nanoparticles (GM-AuNPs) were synthesized and deposited on a supporting membrane to create an easy and stable system for water MB decontamination. GM-AuNPs, with a specific plasmonic band at 535 nm, and the modified membrane were first characterized by UV–vis spectroscopy, X-ray diffraction (XRD), and electron microscopy. Transmission electron microscopy analysis revealed the presence of two breeds of crystalline shapes, triangular platelets and round-shaped penta-twinned nanoparticles, respectively. The crystalline nature of GM-AuNPs was also confirmed from XRD analysis. The photocatalytic performance of the modified membrane was evaluated under natural sunlight radiation, obtaining a complete disappearance of MB (100%) in 116 min. The photocatalytic process was described from a pseudo-first-order kinetic with a rate constant (k) equal to 0.044 ± 0.010 min−1. The modified membrane demonstrated high stability since it was reused up to 20 cycles, without any treatment for 3 months, maintaining the same performance. The GM-AuNPs-based membrane was also tested with other water pollutants (methyl orange, 4-nitrophenol, and rhodamine B), revealing a high selectivity towards MB. Finally, the photocatalytic performance of GM-AuNPs-based membrane was also evaluated in real samples by using tap and pond water spiked with MB, obtaining a removal % of 99.6 ± 1.2% and 98.8 ± 1.9%, respectively. [ABSTRACT FROM AUTHOR]

Anodic TiO2 nanotube arrays decorated with Ni, Cu, and NiCu alloy thin films were investigated for the first time for the photocatalytic degradation of paracetamol in water solution under UV irradiation. Metallic co-catalysts were deposited on TiO2 nanotubes using magnetron sputtering. The influence of the metal layer composition and thickness on the photocatalytic activity was systematically studied. Photocatalytic experiments showed that only Cu-rich co-catalysts provide enhanced paracetamol degradation rates, whereas Ni-modified photocatalysts exhibit no improvement compared with unmodified TiO2. The best-performing material was obtained by sputtering a 20 nm thick film of 1:1 atomic ratio NiCu alloy: this material exhibits a reaction rate more than doubled compared with pristine TiO2, enabling the complete degradation of 10 mg L−1 of paracetamol in 8 h. The superior performance of NiCu-modified systems over pure Cu-based ones is ascribed to a Ni and Cu synergistic effect. Kinetic tests using selective holes and radical scavengers unveiled, unlike prior findings in the literature, that paracetamol undergoes direct oxidation at the photocatalyst surface via valence band holes. Finally, Chemical Oxygen Demand (COD) tests and High-Resolution Mass Spectrometry (HR-MS) analysis were conducted to assess the degree of mineralization and identify intermediates. In contrast with the existing literature, we demonstrated that the mechanistic pathway involves direct oxidation by valence band holes. [ABSTRACT FROM AUTHOR]

The transition from lab-scale studies to pilot-scale applications is a critical step in advancing water remediation technologies. While laboratory experiments provide valuable insights into the underlying mechanisms and method effectiveness, pilot-scale studies are essential for evaluating their practical feasibility and scalability. This progression addresses challenges related to operational conditions, effectiveness and energy requirements in real-world scenarios. In this study, the potential of nanopulsed plasma bubbles, when scaled up from a lab environment, was explored by investigating critical experimental parameters, such as plasma gas, pulse voltage, and pulse repetition rate, while also analyzing plasma-treated water composition. To validate the broad effectiveness of this method, various classes of highly toxic organic pollutants were examined in terms of pollutant degradation efficiency and energy requirements. The pilot-scale plasma bubble reactor generated a high concentration of short-lived reactive species with minimal production of long-lived species. Additionally, successful degradation of all pollutants was achieved in both lab- and pilot-scale setups, with even lower electrical energy-per-order (EEO) values at the pilot scale, 2–3 orders of magnitude lower compared to other advanced oxidation processes. This study aimed to bridge the gap between lab-scale plasma bubbles and upscaled systems, supporting the rapid, effective, and energy-efficient destruction of organic pollutants in water. [ABSTRACT FROM AUTHOR]

The challenge of microcontaminants (MCs) in wastewater effluent has been addressed by using different technologies, including advanced oxidation processes (AOPs) and adsorption. This work evaluates the benefits and synergies of combining these two processes. The AOPs were photo-Fenton and UV/H2O2 operated under natural pH but with different reagents dosages, lamps, and chelating agents. Chelating agents were used at analytical (ethylenediamine-N,N-disuccinic acid and citric acid) and technical grade (citric acid) to simulate scaling-up conditions. The adsorption process was studied via granular activated carbon (GAC) filtration using fresh and regenerated GAC. Four AOP scenarios were selected and coupled with GAC filtration, showing benefits for both processes. AOP treatment time decreased from 10–15 min to 5 min, resulting in a reduction in energy consumption of between 50 and 66%. In the photo-Fenton process, it was possible to work with low reagent dosages (1.5 mg L−1 iron and 20 mg L−1 of H2O2). However, the use of UV/H2O2 showed close removal, highlighting it as a real alternative. An extension of the GAC lifetime by up to 11 times was obtained in all the scenarios, being higher for regenerated than for fresh GAC. Furthermore, the toxicity and phytotoxicity of the treated wastewater were evaluated, and no acute toxicity or slight variation in the phytotoxicity was observed in the combination of these processes. [ABSTRACT FROM AUTHOR]

The objective of this study is to map, describe, and identify "water treatment using catalysts and/or nanomaterials" and their derivable aspects. A comprehensive search was conducted in academic databases such as WoS and Scopus, following the PRISMA methodology, to identify relevant studies published between 2010 and 2024. Inclusion and exclusion criteria were applied to select articles that address both experimental and theoretical aspects of photocatalysis in wastewater treatment. The methodology is developed through exploratory data analysis and the use of the Tree of Science algorithm. The first results indicate the roots, in which it is possible to gain knowledge of the environment for the implementation of a photoreactor it uses as a photocatalyst agent. A total of 94 relevant articles were identified. The results show that most studies focus on the degradation of organic pollutants using TiO2 as a photocatalyst. Additionally, there has been a significant increase in the number of publications and citations in recent years, indicating growing interest in this field. Then, in the trunk, some more solid ideas in terms of basic concepts, techniques and possible variations for the application of knowledge and development of future research related to the initial topic are indicated. Finally, through the leaves, new modifications and combinations of the photocatalytic materials are obtained, in search of improving their performance in terms of reduction in water contaminants. From the above, centrality in photocatalysis is identified as an alternative for water remediation using different photocatalysts. It is concluded that the total citation network contains, within the most important nodes, articles of high interest in the community, such as those authored by Zhang, Xiaofei; Nezamzadeh-Ejhieh, Alireza; or Li, Jingyi, from countries in the Middle East and the Asian continent, justified not only by the research capabilities of these countries, but also by the needs and problems that these regions face in terms of water scarcity. Future work indicates the need for and interest in improving various characteristics such as photocatalytic performance, the number of cycles that the material supports, and its reduction capacity in the presence of high concentrations of contaminants, with the intention of maximizing the benefits of its applicability in water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient dual-adsorption of MO and Cd(II) using biogenic fibrous silica. • Crown ether ionic liquid functionalization enhances pollutant interaction with the adsorbent. • Sustainable adsorbent derived from sorghum waste prepared by an eco-friendly synthesis. • Adsorption processes confirmed as spontaneous and highly efficient. • High surface area and pore volume of the adsorbent provide abundant active sites. In pursuit of sustainable nanomaterial production, this study presents a novel biogenic fibrous silica sphere functionalized with a crown ether ionic liquid for advanced dual-adsorption of methyl orange and Cd(II) from aqueous solution. Sorghum waste serves as the silica source in the adsorbent preparation process, ensuring an eco-friendly approach. The benzo-15-crown-5 ionic liquid is coupled to thiol-functionalized fibrous silica spheres through an efficient thiol-ene click reaction. Under constant conditions (temperature: 298 K, solution volume = 50 mL, adsorbent dosage = 5 mg, pH = 7, shaking speed = 200 rpm), the synthesized material demonstrates maximum adsorption capacities of 507.1 mg g−1 and 306.3 mg g−1 for methyl orange and Cd(II), respectively, according to the Langmuir model. Thermodynamic investigations reveal exothermic adsorption for methyl orange with an enthalpy change of −77.49 KJ mol−1, while endothermic adsorption is observed for Cd(II) with an enthalpy of +24.10 KJ mol−1. The entropy change of adsorption is −0.153 KJ mol−1 K−1 for methyl orange, indicating a more ordered state, and + 0.192 KJ mol−1 K−1 for Cd(II), suggesting increased disorder. The change in Gibbs free energy ranges from −32.66 to −29.60 KJ mol−1 for methyl orange and −32.29 to −35.99 KJ mol−1 for Cd(II), demonstrating that both adsorption processes are spontaneous. These results indicate that the adsorbent has potential as a dual-adsorption material for water remediation applications. [ABSTRACT FROM AUTHOR]

The cashew nut shell is an agricultural residue generated in the production of cashew nuts. This residue is a hard-management biomass that can be efficiently transformed using pyrolysis, into a biochar. Conversely, potable water security requires the development of efficient adsorbents using novel and renewable materials. Then, in this work, a pyrolysis-derived carbon was chemically activated with KOH to remove phenol from an aqueous solution at 200 ppm that could represent health risk for life. The activated carbon was characterized rigorously, whereas adsorption kinetics and adsorption isotherms were evaluated to determine the suitability of this material to remove phenol. The activated carbon presented a chemical composition of 64.4 wt%; 33.2 wt%, and 1.98 wt% of carbon, oxygen, and hydrogen, respectively. Also, it presented a surface adsorption area of 863 m2/g, with a pore volume of 0.476 cm3/g. The surface chemistry presented -OH groups and the morphology revealed an organized material with the occurrence of porosity. The pseudo-second-order adequately described the kinetics of adsorption (80.93 mg/g and 0.0044 g/mg min, for equilibrium concentration (qe), and adsorption rate constant (kPSO), respectively). Additionally, the Toth isotherm model described reasonably the adsorption mechanism suggesting that a monolayer chemisorption that is independent of concentration of phenol took place for activated carbon. The efficiency of phenol uptake in the present work was about 79%, indicating that activated carbon derived from cashew nut shells has the potential for water remediation. [ABSTRACT FROM AUTHOR]

Nanorobots are being received with a great attention for their move‐sense‐and‐act capabilities that often originate from catalytic decomposition of fuels. In the past decade, single‐atom engineering has demonstrated exceptional efficiency in catalysis, energy‐related technologies, and medicine. Here, a novel approach involving point defect engineering and the incorporation of platinum (Pt) single atoms and atomic level species onto the surface of titanium dioxide nanotubes (TiO2‐NT)‐based nanorobots is presented and its impact on the propulsion capabilities of the resulting nanorobots is investigated. The achievement of point defect engineering is realized through the annealing of TiO2‐NT in a hydrogen atmosphere yielding to the point‐defect decorated nanotube (TiO2‐HNT) nanorobots. Subsequently, the atomic level Pt species decorated TiO2 nanotube (TiO2‐SA‐NT) nanorobots are achieved through a wet‐chemical deposition process. Whereas TiO2‐SA‐NT nanorobots showed the highest negative photogravitaxis when irradiated with ultraviolet (UV) light, TiO2‐HNT nanorobots reached the highest velocity calculated in 2D. Both TiO2‐HNT and TiO2‐SA‐NT nanorobots demonstrated a pronounced affinity for microplastics, exhibiting the capability to irreversibly capture them. This pioneering approach utilizing point‐defect and atomic level Pt species nanorobotics is anticipated to pave the way for highly efficient solutions in the remediation of nano‐ and microplastics and related environmental technologies. [ABSTRACT FROM AUTHOR]

Introduction: Overusing and misusing pesticides, including paraquat (PQ), have led to numerous environmental contamination complications. PQ is an emerging bio-accumulative contaminant that is present in environmental aqueous matrices. Adsorption techniques are part of a set of technologies applied in ecological remediation, known for their high effectiveness in removing aqueous PQ. A study of the PQ adsorption capacity of three cyclodextrin-silica nanocomposites (a-CDSi, p-CDSi, and y-CDSi) from contaminated waters is presented in this paper. Methods: The cyclodextrin-silica nanocomposites were synthesized via an esterification reaction between the inorganic matrix and cyclodextrins (CDs) (a, p, and Y) and were characterized physicochemically by spectroscopic, thermal, and surface methods. Their PQ removal performance from contaminated aqueous media was studied under different experimental conditions. Results and Discussion: The results showed a fast adsorptive response in removal treatment studies over time. Adsorption capacities of 87.22, 57.17, and 77.27 mg.g-1 were found for a-CDSi, p-CDSi, and Y-CDSi, respectively, at only 30 min of treatment. Thermodynamic studies indicated spontaneous and exothermic adsorption processes. The removal assays responded mainly to physisorption mechanisms with contributions from chemisorption mechanisms. Spectroscopic assays showed a strong interaction of PQ with the adsorbents used. Innovative CDSi nanocomposites have proven to be highly efficient in applying aqueous PQ remediation, thus proving to be sustainable adsorbents of contaminants of emerging importance worldwide. [ABSTRACT FROM AUTHOR]

Progesterone (PGT) is a steroid hormone produced naturally by pregnant women. Advent of pharmaceuticals gave rise to synthetic production of PGT as a medicine for various pregnancy-related issues. As a result of synthetic production and high utilization rate of PGT, they have become an emerging contaminant in water sources worldwide. Conventional wastewater treatment is not competent enough to remove steroid contaminants. Hence, the current study attempted the degradation of 10 mg L−1 of PGT in water using photocatalysis (PC) followed by electrocatalytic oxidation (EC) using vanadium pentoxide (V2O5) and carbon-coated titanium (C/Ti) anode. Optimization studies found UV-C irradiation, pH 5, 50-mg L−1 catalyst dosage, 180-min PC followed by 300-min EC, and 69 mA cm−2 current density eliminating 96% COD and 71.5% TOC. Comparative studies showed that PC(UV-C) + EC was 50% and 25% more efficient than electrochemical oxidation and electrocatalytic oxidation for TOC removal. Photocatalytic pretreatment brought down current consumption of the process by 23 mA cm−2. High-resolution mass spectrometry (HRMS) studies were utilized to propose the degradation pathway that involved hydroxylation, demethylation, dehydroxylation, and decarboxylation mechanisms. [ABSTRACT FROM AUTHOR]

The development of cost-effective and high-performance technologies for wastewater treatment is essential for achieving a sustainable economy. Among the various methods available for water remediation, adsorption is widely recognized as an effective and straightforward approach for removing a range of pollutants. Gel materials, particularly hydrogels and aerogels, have attracted significant research interest due to their unique properties. Hydrogels, for instance, are noted for their ability to be regenerated and reused, ease of separation and handling, and suitability for large-scale applications. Additionally, their low cost, high water absorption capacity, and contribution to environmental protection are important advantages. Aerogels, on the other hand, are distinguished by their low thermal conductivity, transparency, flexibility, high porosity, mechanical strength, light weight, large surface area, and ultralow dielectric constant. This review provides a comprehensive analysis of the current literature, highlighting gaps in knowledge regarding the classification, preparation, characterization, and key properties of these materials. The potential application of hydrogels and aerogels in water remediation, particularly in removing contaminants such as dyes, heavy metals, and various organic and inorganic pollutants, is also discussed. [ABSTRACT FROM AUTHOR]

The increasing global concern over the contamination of natural resources, especially freshwater, has intensified the need for effective water treatment methods. This article focuses on the utilization of Cellulose nanocrystals (CNCs), sourced from lignocellulosic materials, for addressing environmental challenges. CNCs a product of cellulose-rich sources has emerged as a versatile and eco-friendly solution. CNCs boast unique chemical and physical properties that render them highly suitable for water remediation. Their nanoscale size, excellent biocompatibility, and recyclability make them stand out. Moreover, CNCs possess a substantial surface area and can be modified with functional groups to enhance their adsorption capabilities. Consequently, CNCs exhibit remarkable efficiency in removing a wide array of pollutants from wastewater, including heavy metals, pesticides, dyes, pharmaceuticals, organic micropollutants, oils, and organic solvents. This review delves into the adsorption mechanisms, surface modifications, and factors influencing CNCs' adsorption capacities. It also highlights the impressive adsorption efficiencies of CNC-based adsorbents across diverse pollutant types. Employing CNCs in water remediation offers a promising, eco-friendly solution, as they can undergo treatment without producing toxic intermediates. As research and development in this field progress, CNC-based adsorbents are expected to become even more effective and find expanded applications in combating water pollution. [ABSTRACT FROM AUTHOR]

Tribocatalysis is an emerging advanced oxidation process that utilizes the triboelectric effect, based on friction between dissimilar materials to produce charges that can initiate various catalytic reactions. In this study, pure and rare-earth-modified ZnO powders (La2O3, Eu2O3, 2 mol %) were demonstrated as efficient tribocatalysts for the removal of the tetracycline antibiotic doxycycline (DC). While the pure ZnO samples achieved 49% DC removal within 24 h at a stirring rate of 100 rpm, the addition of Eu2O3 increased the removal efficiency to 67%, and La2O3-modified ZnO powder exhibited the highest removal efficiency, reaching 80% at the same stirring rate. Additionally, increasing the stirring rate to 300 and 500 rpm led to 100% DC removal in the ZnO/La case within 18 h, with the pronounced effect of the stirring rate confirming the tribocatalytic effect. All tribocatalysts exhibited excellent recycling properties, with less than a 3% loss of activity over three cycles. Furthermore, a scavenger assay confirmed the importance of superoxide radical generation for the overall reaction rate. The results of this investigation indicate that the rare-earth-modified ZnO tribocatalysts can effectively utilize mechanical energy to decompose pollutants in contaminated water. [ABSTRACT FROM AUTHOR]

This study demonstrated the synthesis of Fe2MnO4 modified by citric acid, a biodegradable acid, using a simple co-precipitation method. Characterization was performed using qualitative analysis techniques such as Fourier-transformed infrared spectroscopy, scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy, X-ray diffraction, selected-area electron diffraction, N2 adsorption–desorption, and zero-point charge. The prepared nanoparticles had a rough and porous surface, and contained oxygenous (-OH, -COOH, etc.) functional groups. The specific surface area and average pore size distribution were 83 m2/g and 5.17 nm, respectively. Net zero charge on the surface of the prepared nanoparticles was observed at pH 7.5. The prepared nanoparticles were used as an adsorbent to remove methylene blue dye from water under various conditions. Using small amounts of the adsorbent (2.0 g/L), even a high concentration of MB dye (60 mg/L) could be reduced by about ~58%. Exothermic, spontaneous, feasible, and monolayer adsorption was identified based on thermodynamics and isotherm analysis. Reusability testing verified the stability of the adsorbent and found that the reused adsorbent performed well for up to three thermal cycles. Comparative analysis revealed that the modified adsorbent outperformed previously reported adsorbents and unmodified Fe2MnO4 in terms of its partition coefficient and equilibrium adsorption capacity under different experimental conditions. [ABSTRACT FROM AUTHOR]

Leveraging date palm spikelets (DPS) as a precursor, this study developed a DPS-derived composite (ZnO@DPS-AC) for water treatment, focusing on methyl orange (MO) removal. The composite was synthesized through ZnCl2 activation and pyrolysis at 600 °C. Comprehensive characterization was conducted using TGA, FTIR, XRD, SEM/EDS, and pHPZC. Characterization revealed a highly carbonaceous material (> 74% carbon) with significant porosity and surface functional groups. ZnO@DPS-AC demonstrated rapid MO removal, achieving over 45% reduction within 10 min and up to 99% efficiency under optimized conditions. The Langmuir model-calculated maximum adsorption capacity reached 226.81 mg/g at 20 °C. Adsorption mechanisms involved hydrogen bonding, π-π interactions, and pore filling. The composite showed effectiveness in treating real wastewater and removing other pollutants. This study highlights the potential of agricultural waste valorization in developing efficient, sustainable adsorbents for water remediation, contributing to circular bioeconomy principles. [ABSTRACT FROM AUTHOR]

To align with the national polices of energy saving and pollution reduction, a comprehensive design experiment was devised. Students are guided through the synthesis of copper(I) oxide nanoparticles and its subsequent application in the remediation of dye wastewater, examining the influence of various experimental conditions on the degradation efficiency. This experiment not only covers fundamental laboratory skills and the use of common instruments, but also introduces students to advanced concepts like nanomaterials preparation, oxidation degradation, and aquatic remediation. By adopting a research-oriented teaching approach, this experiment fosters independent thinking among students, effectively developing the scientific research and innovation abilities of undergraduates in lower grades and enhancing their sense of social responsibility. [ABSTRACT FROM AUTHOR]

Trace concentrations of dyes are often present in textile wastewater streams and present a serious environmental problem. Thus, these dyes must be removed from wastewater either by degradation or sequestration prior to discharge of the wastewater into the environment. Existing processes to remove these wastewater contaminants include the use of solid sorbents to sequester dyes or the use of biochemical or chemical methods of dye degradation. However, these processes typically generate their own waste products, are not necessarily rapid because of the low dye concentration, and often use expensive or non-recyclable sequestrants or reagents. This paper describes a simple, recyclable, liquid–liquid extraction scheme where ionic dyes can be sequestered into poly(α-olefin) (PAO) solvent systems. The partitioning of anionic and cationic dyes from water into PAOs is facilitated by ionic PAO-phase anchored sequestering agents that are readily prepared from commercially available vinyl-terminated polyisobutylene (PIB). This is accomplished by a sequence of reactions involving hydroboration/oxidation, conversion of an alcohol into an iodide, and conversion of the resulting primary alkyl iodide into a cationic nitrogen derivative. The products of this synthetic sequence are cationic nitrogen iodide salts which serve as anionic sequestrants that are soluble in PAO. These studies showed that the resulting series of cationic PIB-bound cationic sequestering agents facilitated efficient extraction of anionic, azo, phthalein, and sulfonephthalein dyes from water into a hydrocarbon PAO phase. Since the hydrocarbon PAO phase is completely immiscible with water and the PIB derivatives are also insoluble in water, neither the sequestration solvent nor the sequestrants contaminate wastewater. The effectiveness and efficiency of these sequestrations were assayed by UV–visible spectroscopy. These spectroscopic studies showed that extraction efficiencies were in most cases >99%. These studies also involved procedures that allowed for the regeneration and recycling of these PAO sequestration systems. This allowed us to recycle the PAO solvent system for at least 10 sequential batch extractions where we sequestered sodium salts of methyl red and 4′,5′-dichlorofluorescein dyes from water with extraction efficiencies of >99%. These studies also showed that a PIB-bound derivative of the sodium salt of 1,1,1-trifluoromethylpentane-2,4-dione could be prepared from a PIB-bound carboxylic acid ester by a Claisen-like reaction and that the sodium salt of this β-diketone could be used to sequester cationic dyes from water. This PIB-bound anion rapidly and efficiently extracted >99% of methylene blue, malachite green, and safranine O from water based on UV–visible and 1H NMR spectroscopic assays. [ABSTRACT FROM AUTHOR]

Fluoride has become a globally concerning pollutant due to its potential toxicity and negative health impacts. Adsorption has been regarded as the most promising approach for the elimination of fluoride contamination owing to its cost-effectiveness and high efficiency. Nanomaterials are excellent adsorbents for defluoridation due to their high specific surface area, high adsorption properties, and ease of self-assembly. However, there are still some challenges in the application of nanoadsorbents for wastewater treatment. Therefore, this review summarizes the research progress of nanoadsorbents for fluoride removal and develops a fundamental understanding of the structure and adsorption properties of nanoadsorbents in different dimensions. It studies the synergistic effects of different nano- components in adsorption capabilities. In addition, challenges related to the engineering applications of nanoadsorbents and some suggestions to address these issues are presented to promote their practical application prospects. [ABSTRACT FROM AUTHOR]

Contamination of water resources with cesium poses a significant environmental threat, necessitating effective remediation strategies. This manuscript explores the potential of Nigella Sativa, commonly known as black seed, as a novel and sustainable solution for mitigating cesium contamination in water. Through a series of controlled experiments, the adsorption and removal efficiency of Nigella Sativa for cesium ions were investigated. Our findings reveal promising results, highlighting the ability of Nigella Sativa to effectively reduce cesium concentrations in water from 0.0 to 64 % at constant pH for water and changing the concentration of nano nigella sativa (NSN) concentration. But when the pH of the water is changed from 3 to 11 and the NSN concentration value is fixed at 5 mg, the efficiency of removing cesium from polluted water will change. It was found that the best removal was at the pH value of 5. The unique chemical composition of Nigella Sativa seeds, rich in active compounds, demonstrates its potential as a natural and cost-effective material for water remediation. This research contributes to the development of eco-friendly approaches for cesium decontamination, with implications for environmental and public health. Further exploration of the mechanisms involved and the scalability of this remediation method is recommended for future applications. [ABSTRACT FROM AUTHOR]

The use of biobased substances derived from industrial and household waste as renewable raw materials for environmental applications is gaining prominence due to its sustainable and cost-effective approach to waste valorisation. Herein, we report the uptake of paraquat, a widely used pesticide, by magnetite nanoparticles coated with composted urban biowaste-derived substances (MNP-BBS). The magnetic nanoparticles were prepared using a modified co-precipitation method, and were characterized through various physicochemical techniques. They were tested as an adsorbent for paraquat removal under diverse experimental conditions, exploring the influence of pH (3–10), MNP-BBS dosages (200–1000 mg L−1), ionic strength (0–0.01 M), and presence of organic matter. The kinetic study revealed that the adsorption of paraquat onto MNP-BBS follows the pseudo-second-order model, reaching the adsorption equilibrium after 2 h of contact and 90% of paraquat removal in the best condition tested (1000 mg L−1). The equilibrium experimental data showed a high adsorption performance with a good fitting to the Freundlich isotherm model. Also, from Langmuir model a maximum adsorption capacity of 0.085 mmol g−1 was estimated. The results indicated that electrostatic interaction between the negative functional groups of the adsorbent and the paraquat play a major role in the adsorption mechanism, although the contribution of π-π and hydrophobic interactions cannot be completely ruled out. This research underscores the potential of utilizing MNP-BBS as an effective adsorbent for the removal of paraquat, shedding light on its application in sustainable water purification processes. [ABSTRACT FROM AUTHOR]

The metal intoxication and its associated adverse effects to humans have led to the research for development of water treatment technologies from pollution hazards. Therefore, development of cheaper water remediation technologies is more urgent than ever. Clays and clay minerals are naturally occurring, inexpensive, non-toxic materials possessing interesting chemical and physical properties. As a result of interesting surface properties, these have been developed as efficient absorbent in water remediation. Recently, clay–polymer nanocomposites have provided a cost-effective technological platform for removing contaminants from water. Covering research advancements from past 25 years, this review highlights the developments in clay–polymer nanocomposites and their advanced technical applications are evaluated with respect to the background and issues in remediation of toxic metals and organic compounds from water. The extensive analysis of literature survey of more than two decades suggests that future work need to highlight on advancement of green and cost-effective technologies. The development of understanding of the interaction and exchange between toxin and clay–polymer composites would provide new assembly methods of nanocomposites with functional molecules or nanomaterials need to be extended to increase the detection and extraction limit to parts per trillion. [ABSTRACT FROM AUTHOR]

One of the hottest research topics over the last decades was the valorization or/and recycling of agro-industrial wastes into different valuable liquid or solid products, which is considered a sustainable and low-cost approach. In this study, we developed zero-valent iron nanoparticles from Palm Petiole Extract (P-NZVI) using a green and straightforward approach. The as-synthesized P-NZVI was used to adsorb Cr(VI) in water. The physico-chemical characterizations of P-NZVI, including the particle size, crystalline structure, surface area, morphology, and functional groups, were investigated via several techniques such as UV-vis spectroscopy, SEM, TEM, XRD, FTIR, AFM, DLS, pHZPC measurement, and BET analysis. The adsorption performance of P-NZVI was studied under different operational parameters, including pollutant concentration, pH, temperature, and adsorbent mass. The adsorption rate was found to be 89.3% within 40 min, corresponding to the adsorption capacity of 44.47 mg/g under the following conditions: initial Cr(VI) concentration of 40 mg/L, pH 5, and a P-NZVI dosage of 1 g/L. It was found that the adsorption pattern follows the Langmuir and the pseudo-second-order kinetic models, indicating a combination of monolayer adsorption and chemisorption mechanisms. The thermodynamic study shows that the adsorption process is endothermic and spontaneous. The reusability of P-NZVI was carried out four times, showing a slight decrease from 89.3 to 87%. These findings highlight that P-NZVI's could be an effective green adsorbent for removing Cr(VI) or other types of toxic pollutants from water. [ABSTRACT FROM AUTHOR]

This review paper discusses the latest advances in transfiguring Azadirachta indica (neem) biomass into an adsorbent and how it can be used to clean the environment. As an economical and environmentally favorable adsorbent material, neem biomass has become increasingly popular due to its bioactive properties and abundance. The review breaks down modification techniques into chemical and physical processes. Important physical changes covered include preactivation, carbonization, and using fluidized bed technologies and rotary kilns. It has been shown that these methods greatly improve the surface properties of neem biomass, which makes it better at absorbing things and holding more. The changes that were made also have an effect on the adsorption kinetics and isotherms, which helps us understand the adsorption rates and equilibrium behaviors of the changed adsorbents better. Neem biomass adsorbents are illustrated through their versatility and efficacy in the removal of organic pollutants, dyes, and heavy metals from effluent. This is illustrated through specific applications. Additionally, computational studies and artificial intelligence are looked into to see if they can help us understand how adsorption works at the molecular level, improve the efficiency of modification processes, and guess how adsorption will behave. The review also talks about the research gaps and suggests areas for future research. The review emphasizes the crucial importance of integrating experimental and computational methods to enhance the performance of the modified neem biomass and increase its environmental cleaning potential.

Abstract Green and efficient agro-waste-based activated carbon has been prepared utilizing peanut shells for adsorptive elimination of an industrial dye, methylene blue, and lead from polluted water. The carbonaceous biomass obtained from peanut shells was chemically activated using either NaOH, ZnCl2, or steam and characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy, and N2 adsorption and desorption studies. The adsorption process was optimal for methylene blue at alkaline pH, while pH 4.5 was optimal for Pb (II) adsorption. The adsorption takes place through pseudo-second-order kinetic, and the rate-governing step of the adsorption procedure are intraparticle diffusion and film diffusion. Furthermore, the thermodynamics of the adsorption process has been studied, and the obtained Gibbs free energy (ΔG°) values are negative (− 35.90 to − 43.59 kJ mol−1) indicating the spontaneous adsorption of the investigated pollutants on the prepared activated carbon. As per the correlation coefficient, the obtained results were best fit by the Langmuir isotherm with maximum adsorption capacity of 303.03 mg g−1 for methylene blue and 130.89 mg g−1 for Pb (II). The activated carbon successfully removed methylene blue and Pb (II) with %removal exceeding 95%. The mechanisms of interaction of Pb (II) with the activated carbon is a combination of electrostatic interaction and ion exchange, while methylene blue interacts with the activated carbon via π–π interaction, hydrogen bonds, and electrostatic interaction. Thus, the prepared activated carbon has been employed to decontaminate wastewater and groundwater samples. The developed agro-waste-based activated carbon is a promising, cost-efficient, green, and accessible tool for water remediation.

Abstract Pharmaceutical active compounds (PhACs) are some of the most recalcitrant water pollutants causing undesired environmental and human effects. In absence of adapted decontamination technologies, there is an urgent need to develop efficient and sustainable alternatives for water remediation. Metal–organic frameworks (MOFs) have recently emerged as promising candidates for adsorbing contaminants as well as providing photoactive sites, as they possess exceptional porosity and chemical versatility. To date, the reported studies using MOFs in water remediation have been mainly focused on the removal of a single type of PhACs and rarely on the combined elimination of PhACs mixtures. Herein, the eco-friendly bismuth-based MOF, SU-101, has been originally proposed as an efficient adsorbent-photocatalyst for the elimination of a mixture of three challenging persistent PhACs, frequently detected in wastewater and surface water in ng L−1 to mg·L−1 concentrations: the antibiotic sulfamethazine (SMT), the anti-inflammatory diclofenac (DCF), and the antihypertensive atenolol (At). Adsorption experiments of the mixture revealed that SU-101 exhibited a great adsorption capacity towards At, resulting in an almost complete removal (94.1 ± 0.8% for combined adsorption) in only 5 h. Also, SU-101 demonstrated a remarkable photocatalytic activity under visible light to simultaneously degrade DCF and SMT (99.6 ± 0.4% and 89.2 ± 1.4%, respectively). In addition, MOF-contaminant interactions, the photocatalytic mechanism and degradation pathways were investigated, also assessing the toxicity of the resulting degradation products. Even further, recycling and regeneration studies were performed, demonstrating its efficient reuse for 4 consecutive cycles without further treatment, and its subsequent successful regeneration by simply washing the material with a NaCl solution.

ZnO films were obtained by electrodeposition technique from commercial Zn2+ solutions and those obtained from spent alkaline batteries. The type of counterion and pH impact directly on the structural, morphological, and optical properties of the electrodeposited ZnO films. The morphological and crystallographic orientation differences observed by X‐ray diffraction (XRD) analysis and high‐resolution field emission scanning electron microscopy (HR‐FESEM), demonstrates the influence of the type and origin of precursors used in the ZnO synthesis process. Those samples grown from commercial nitrate solutions exhibit nanocolumns revealing a preferential growth in the (002) direction. On the other hand, random growth (hexagonal plates, agglomerations, clusters, etc.) is observed in samples obtained through recycled solutions. All deposited samples achieved a transparency close to 80 % and an optical band gap of around 3.30 eV. The as‐deposited films were evaluated toward the photodegradation capacity of methylene blue (MB) for potential technological applications. Results exhibit that samples prepared from recycled ZnCl2 solutions presented more than 80 % degradation per mass of ZnO. This work demonstrates a virtuous circle since ZnO films are deposited by a facile and scalable technique from discarded batteries and used for MB photodegradation. Furthermore, the simplicity of recovery of these substrates after application makes them an attractive and pragmatic option for a range of water treatment applications. Synopsis: Zinc from depleted alkaline batteries is reused to obtain ZnO thin films that remove contaminating dyes from water. [ABSTRACT FROM AUTHOR]

Endophytic microorganisms contribute significantly to water bioremediation by enhancing pollutant degradation and supporting aquatic plant health and resilience by releasing bioactive compounds and enzymes. These microorganisms inhabit plant tissues without causing disease or any noticeable symptoms. Endophytes effectively aid in eliminating contaminants from water systems. Nanoparticles serve as potent enhancers in bioremediation processes, augmenting the efficiency of pollutant degradation by increasing surface area and bioavailability, thereby improving the efficacy and rate of remediation. Their controlled nutrient release and ability to stabilize endophytic colonization further contribute to the enhanced and sustainable elimination of contaminated environments. The synergistic effect of endophytes and nanoparticles in water remediation has been widely explored in recent studies, revealing compelling outcomes. Water pollution poses significant threats to human health, ecosystems, and economies; hence, the sixth global goal of the Sustainable Development Agenda 2030 of the United Nations aims to ensure the availability and sustainable management of water resources, recognizing their crucial importance for current and future generations. Conventional methods for addressing water pollution exhibit several limitations, including high costs, energy-intensive processes, the production of hazardous by-products, and insufficient effectiveness in mitigating emerging pollutants such as pharmaceuticals and microplastics. Noticeably, there is an inability to effectively remove various types of pollutants, thus resulting in incomplete purification cycles. Nanoparticle-enhanced water bioremediation offers an innovative, eco-friendly alternative for degrading contaminants. A growing body of research has shown that integrating endophytic microorganisms with nanoparticles for water bioremediation is a potent and viable alternative. This review examines the potential of using endophytic microorganisms and nanoparticles to enhance water remediation, exploring their combined effects and applications in water purification. The paper also provides an overview of synthetic methods for producing endophyte–nanoparticle composites to optimize their remediation capabilities in aqueous environments. The final section of the review highlights the constraints related to integrating endophytes with nanoparticles. [ABSTRACT FROM AUTHOR]

Introduction: The endorsement of circular economy, zero-waste, and sustainable development by the EU and UN has promoted non-thermal technologies in agro-food and health industries. While northern European countries rapidly integrate these technologies, their implementation in Mediterranean food-supply chains remains uncertain. Aims: We evaluated the usefulness of hydrodynamic cavitation (HC) for valorizing orange peel waste in the fresh orange juice supply chain of the Maltese Islands. Method: We assessed: a) the effectiveness of HC in extracting bioactive compounds from orange peels (Citrus sinensis) in water (35°C) and 70% (v/v) ethanol (-10°C) over time, compared to conventional maceration, and b) the potato sprouting-suppression and biosorbent potential of the processed peel for copper, nitrate, and nitrite binding. Results: Prolonged HC-assisted extractions in water (high cavitation numbers), damaged and/or oxidized bioactive compounds, with flavonoids and ascorbic acid being more sensitive, whereas cold ethanolic extractions preserved the compounds involved in radical scavenging. HC-processing adequately modified the peel, enabling its use as a potato suppressant and biosorbent for copper, nitrate, and nitrite. Conclusion: Coupling HC-assisted bioactive compound extractions with using leftover peel for potato-sprouting prevention and as biosorbent for water pollutant removal offers a straightforward approach to promoting circular economic practices and sustainable agriculture in Malta. [ABSTRACT FROM AUTHOR]

In this study, we report on the synthesis of ternary photocatalysts comprising TiO2/SnO2/g-C3N4 for the degradation of ciprofloxacin (CIP) in water. SnO2 nanoparticles were synthesized via the sol–gel method, while g-C3N4 was obtained through melamine calcination. Commercial TiO2 and SnO2 nanopowders were also used. The heterojunctions were synthesized via the wet impregnation method. The photocatalysts were characterized via various techniques, including XRD, TEM, STEM, FTIR, N2 adsorption, UV–Vis DR, and hole tests. Photocatalytic degradation tests of CIP were carried out under UV, visible, and solar radiation. The P25/npA/g-C3N4 (90/10) material exhibited the best performance, achieving CIP degradation of over 97%. The synthesized materials demonstrated excellent initial adsorption of CIP, around 30%, which facilitated subsequent degradation. Notably, the CIP photocatalytic degradation tests performed under solar radiation showed a synergistic effect between the base materials and carbon nitride in highly energetic environments. These results highlight the effectiveness of ternary photocatalysts TiO2/SnO2/g-C3N4 for CIP degradation, particularly under solar radiation. [ABSTRACT FROM AUTHOR]

One of the major health problems in present times is the unavailability of clean drinking water, due to the existence of toxic dyes in water. Taking this into account, this work sought to demonstrate the sorption proficiency of a green β-CYCAL (β-Cyclodextrin – Citric Acid – Alginic Acid) polymer sorbent for the effective sorption of toxic dyes Rhodamine B (RhB), Basic Magenta Dye (MgN) and Methylene Blue (MeB) from wastewater. This innovative polymer sorbent was synthesized from green components specifically β-Cyclodextrin (β-CD), Alginic acid and Citric acid in an aqueous media, via solution polymerisation. The structural and chemical attributes of the sorbent have been characterized by using various techniques. For evaluating the sorption capability, the influence of various physicochemical parameters viz. pH, initial dye concentration, contact time and sorbent dosage, were determined and optimized for maximum sorption. Solubility and regeneration studies for the sorbent were conducted. The maximum degree of sorption of RhB, MgN and MeB dyes were found to be 96.43%, 92.42% & 93.50% at a dye concentration of 2 dM. The kinetic investigation of sorption followed pseudo-second-order rate kinetics for the dyes with linear regression constant 0.99628 and the isothermal studies revealed the sorbent satisfy Freundlich adsorption isotherm. From the results of characteristic examination, the fast sorption performance of this polymeric sorbent, in adsorbing the dyes was revealed and demonstrated its viability as an eco-friendly, cost-effective sorbent for wastewater treatment and environmental remediation applications. [ABSTRACT FROM AUTHOR]

Pesticides pose a significant threat to nontargeted organisms, and their pervasive use makes avoidance challenging. We employed nitrogen-doped carbon cryogels for the removal of organophosphate pesticides. The materials were synthesized and characterized using SEM, Raman spectroscopy, XPS, and BET analysis. Results revealed mesoporous cryogels with pore diameters ranging from 3 to 13 nm. Interestingly, the specific surface area did not change systematically with increasing nitrogen content. All investigated materials have similar composition and structural disorder. Dimethoate, malathion, and chlorpyrifos removal was investigated under stationary and dynamic conditions. Stationary conditions demonstrated successful removal of aliphatic dimethoate and malathion by all investigated materials. Conversely, the materials with the lowest and highest nitrogen content proved ineffective with aromatic chlorpyrifos. Under dynamic conditions, all materials effectively removed malathion and chlorpyrifos while exhibiting suboptimal performance for dimethoate adsorption. Application of nitrogen-doped carbon cryogels to tap water spiked with pesticides yielded successful results under the same conditions. Toxicity testing of treated samples revealed a consistent decrease in toxicity, indicating that contact with cryogels reduces the initial solution's toxicity. This result also confirms that material–pesticide interaction does not lead to the formation of more toxic byproducts. The demonstrated efficacy suggests the potential application of these materials in water treatment. [ABSTRACT FROM AUTHOR]

Conventional methods for synthesising polyurethane hydrogels encompass toxic isocyanates and organic solvents, limiting their eco-friendliness and ease of synthesis. In response, this study introduces an innovative approach to synthesising fructose-based non-isocyanate polyurethane (NIPU) hydrogel (FNHG), eliminating the need for isocyanates. Initially, fructose-based NIPU (FNPU) was synthesised using dimethyl carbonate and hexamethylene diamine under mild reaction conditions, paving the way for a greener polyurethane variant. Subsequently, a free radical polymerization technique was employed in an aqueous medium. This process allowed for the integration of poly(sodium acrylate), and N, N-methylene bisacrylamide, leading to to the development of FNHG. Remarkably short gelation time of just 30 min at 60 ℃ was achieved, signifying a significant advancement in the synthesis process. The synthesized NIPU-based hydrogels exhibited outstanding efficiency in the removal of crystal violet (CV) and malachite green (MG) dyes from aqueous media. With an impressive removal efficiency of 96.87% for CV and an astounding 99.8% for MG, these hydrogels demonstrated high effectiveness in remediation efforts. The study's novelty lies in both the synthesis methodology, utilising FNPU, and the exceptional efficiency exhibited by these hydrogels in eliminating diverse dyes from contaminated water. Furthermore, the structure of FNPU was confirmed using FTIR and 1H NMR spectroscopy, adding robustness to our findings. This research not only presents a solution to the limitations of traditional polyurethane synthesis but also demonstrates the potential of fructose-based NIPU hydrogels (FNHG) as eco-friendly and efficient agents for water purification. [ABSTRACT FROM AUTHOR]

This article reports on the synthesis of an innovative smart polymer, P5‐QPDMAEMA, opportunely developed with the aim of combining the responsiveness of PDMAEMA polymer and the host‐guest properties of covalently linked pillar[5]arenes. Thanks to a traditional Non‐Induced Phase Separation (NIPS) process performed at various coagulation pH, the blending of P5‐QPDMAEMA with polyethersulfone gave rise to the formation of functional beads for the removal of organic dyes in water. Adsorption tests are carried out on all the produced blend‐based beads by employing two representative dyes, the cationic methylene blue (MB), and the anionic methyl orange (MO). In particular, the P5‐QPDMAEMA based beads, prepared at acidic pH, featured the best MO removal rate (i. e., 91.3 % after 150 minutes starting from a 20 mg ⋅ L−1 solution) and a high selectivity towards the removal of the selected anionic dye. Based on the adsorption kinetics and isotherm calculations, the pseudo‐first order and Freundlich models were shown to be the most suitable to describe the MO adsorption behavior, achieving a maximum adsorption capacity of 21.54 mg ⋅ g−1. Furthermore, zwitterionic beads are obtained by a post‐functionalization of the PDMAEMA and the P5‐QPDMAEMA based beads, to test their removal capability towards both anionic and cationic dyes, as shown. [ABSTRACT FROM AUTHOR]

Contamination by pharmaceuticals adversely affects the quality of natural water, causing environmental and health concerns. In this study, target drugs (oxazepam, OZ, 17-α-ethinylestradiol, EE2, and drospirenone, DRO), which have been extensively detected in the effluents of WWTPs over the past decades, were selected. We report here a new photoactive system, operating under visible light, capable of degrading EE2, OZ and DRO in water. The photocatalytic system comprised glass spheres coated with nanostructured, solvothermally treated WO3 that improves the ease of handling of the photocatalyst and allows for the implementation of a continuous flow process. The photocatalytic system based on solvothermal WO3 shows much better results in terms of photocurrent generation and photocatalyst stability with respect to state-of-the-art WO3 nanoparticles. Results herein obtained demonstrate that the proposed flow system is a promising prototype for enhanced contaminant degradation exploiting advanced oxidation processes. [ABSTRACT FROM AUTHOR]

We modified C3-symmetric benzene-1,3,5-tris-amide (BTA) by introducing flexible linkers in order to generate an N-centered BTA (N-BTA) molecule. The N-BTA compound formed gels in alcohols and aqueous mixtures of high-polar solvents. Rheological studies showed that the DMSO/water (1:1, v/v) gels were mechanically stronger compared to other gels, and a similar trend was observed for thermal stability. Powder X-ray analysis of the xerogel obtained from various aqueous gels revealed that the packing modes of the gelators in these systems were similar. The stimuli-responsive properties of the N-BTA towards sodium/potassium salts indicated that the gel network collapsed in the presence of more nucleophilic anions such as cyanide, fluoride, and chloride salts at the MGC, but the gel network was intact when in contact with nitrate, sulphate, acetate, bromide, and iodide salts, indicating the anion-responsive properties of N-BTA gels. Anion-induced gel formation was observed for less nucleophilic anions below the MGC of N-BTA. The ability of N-BTA gels to act as an adsorbent for hazardous anionic and cationic dyes in water was evaluated. The results indicated that the ethanolic gels of N-BTA successfully absorbed methylene blue and methyl orange dyes from water. This work demonstrates the potential of the N-BTA gelator to act as a stimuli-responsive material and a promising candidate for water purification. [ABSTRACT FROM AUTHOR]

The extensive industrial use of organic dyes causes large amounts of these substances to arrive at water sources, so nowadays, organic compound removal from fresh water is a major concern. The use of photocatalysts is an interesting approach to solving this problem, with coordination compounds playing an outstanding role. We report the selective synthesis and characterization of three new dissymmetric bis(thiosemicarbazone) ligands and their nickel(II) and zinc(II) complexes, which have been fully characterized by several techniques. The photocatalytic activity of the six complexes for methyl orange degradation was also evaluated. All the complexes can degrade this organic dye, although the photoefficiency of the nickel compounds is, in general, higher than for the zinc ones, as the degradation is faster and they do not reach a plateau. Density functional theory calculations show a clear dependence of the highest occupied molecular orbital (HOMO)–lowest unoccupied molecular orbital (LUMO) gap, as well as with the relative energies of these orbitals. On the other hand, the need for green fuels that do not produce the greenhouse effect is one of the major goals of modern life, and molecular hydrogen is one of the most promising ones. Considering the proven potential of bis(thiosemicarbazone) complexes to electrocatalyze H2 evolution recently reported in the literature, we also made some preliminary tests to investigate the potential of the nickel complexes to act as photocatalysts for water splitting. The results indicate that two of the complexes produce H2 in the conditions tested, so they could be used in the development of efficient photocatalytic systems for hydrogen evolution. [ABSTRACT FROM AUTHOR]