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Climate change leads to more frequent and intense extreme weather events like floods and droughts, which can transport copper (Cu) from soils, sediments, and urban areas into water bodies, and raise copper concentrations during dry periods. Both events may cause an increase in Cu contamination risks in water sources. Therefore, it is paramount significance to mitigate the hazards of Cu pollution in water source by developing an effective method for adsorbing Cu(II) from water bodies. Here, we developed an electrochemical adsorption strategy to achieve this goal by Cu(II) ion-imprinted polymer (Cu-IIP) electrode as mediator. Cu-IIP powders were synthesized by blending two naturally occurring biopolymers, cellulose and sodium alginate (SA), with Cu(NO3)2, epichlorohydrin (ECH), and ethylenediaminetetraacetic acid disodium salt dihydrate (EDTA) serving as the source of template ions, cross-linker, and extraction agent, respectively. IIP were then utilized as adsorbents for Cu(II) at a constant cell voltage under electrochemically controlled reduction process. The findings revealed that the IIP/CC exhibits a maximum adsorption capacity of 31.5 mg/g, showcasing efficient electrodeposition of Cu(II) onto the IIP surface at a concentration of 70 mg/L. These indicate that IIP exhibited excellent adsorption capabilities of Cu(II) ions, enabling the effective and efficient enrichment of Cu(II) in water. [Display omitted] • IIP/CC followed the Langmuir isotherm model, indicating monolayer adsorption capacity. • Chemical adsorption occurs on surface of IIP/CC. • Electrochemical adsorption of Cu(II) at −0.95 V in a controlled potential cell. • IIP/CC achieved a maximum adsorption capacity of 31.5 mg/g for Cu(II) at 70 mg/L. • Cu(II) showed a K d of 0.712, indicating stronger binding affinity in IIP/CC for Cu(II). [ABSTRACT FROM AUTHOR]

In this work, we address the photocatalytic mineralization of single-component solutions and mixtures of three organohalogenated compounds, dexamethasone (DEX), S-metolachlor (MTLC) and dichloroacetic acid (DCA) using a low-cost TiO 2 /rGO composite. A detailed experimental analysis has evidenced the positive influence of the presence of DCA on the degradation, and mineralization kinetics, as well as on the release of ions into solution, which is explained by the acidic pH of the solutions containing this compound. Mineralization curves of the aqueous mixtures follow two distinct kinetic trends, the first is assigned to the breakdown of the primary compounds and proceeds with second order kinetics (k = 0.58 × 10−3 mM−1 min−1 at neutral pH, and k = 1.19 × 10−3 mM−1 min−1 at pH 4 and the tertiary mixture). In the second zone, which progresses at a slower rate and is attributed to the mineralization of intermediate compounds, all mixtures have kinetic constants within the range (9.7 ± 0.7) × 10−3 min−1. The progress in the release of halogen ions (F- and Cl-) and NH 4 +, together with the changes in the chemical composition of the catalyst determined by XPS, allow to conclude that no organohalogenated intermediates remain in solution after treatment. Furthermore, the lack of phytotoxicity of the treated mixtures is confirmed with germination indices (GI), reaching GI values above the control point for the time of complete mineralization; this together with the stability of the catalyst after 5 reuse cycles highlights the green and sustainable nature of the selected photocatalytic remediation process. [Display omitted] • Holistic approach monitoring environmental and toxicity parameters. • Photocatalytic mineralization of OHXs in single-solutions and mixtures. • Kinetic study of mineralization and ions release. • Low-cost easy synthesis TiO 2 /rGO catalysts keep the stability after 5 reuse cycles. • Fully mineralization contributes to photocatalysis sustainability. [ABSTRACT FROM AUTHOR]

The extensive use of plastic products leads to white pollution and the formation of nanoplastics (NPs) through physicochemical processes. Due to their large specific surface area and small size, NPs can easily enter the human body, posing significant health risks. In this work, we prepared NiFe 2 O 4 nanosheets-decorated carbon nanofibers (NiFe 2 O 4 @CNF) via electrospinning, carbonization, hydrothermal growth, and low-temperature calcination for NPs removal. Characterization techniques, including SEM, FTIR, XRD, XPS, and zeta potential analysis, assessed the surface morphology, functional groups, crystal structure, chemical composition, and surface charge of the NiFe 2 O 4 @CNF adsorbent. Adsorption kinetics, isotherms, and thermodynamics studies demonstrated that the adsorption process follows pseudo-second-order kinetics and the Langmuir model, indicating chemisorption and monolayer adsorption with a maximum adsorption capacity of 147.842 mg/g. Thermodynamic data confirmed that the reaction is spontaneous and endothermic. Additionally, the practical application of the adsorbent was evaluated by studying the effects of pH, competing ions, and different water bodies on adsorption behavior, all showing high removal efficiency and robust performance. Computer simulations further provided understanding into the driving forces and the binding sites of adsorption. These results underscore the efficacy of NiFe 2 O 4 @CNF for NPs removal and provide critical insights for designing advanced environmental remediation materials. [Display omitted] • NiFe 2 O 4 @CNF exhibits a removal efficiency of more than 98 % towards nanoplastics. • The design of the nanocomposite adsorbent is guided by theoretical calculations. • Electrospun carbon nanofibers provide robust support for NiFe 2 O 4 nanosheets. • The adsorption process is driven by electrostatic interaction and metal complexation. • The maximum adsorption capacity of the adsorbent was 147.842 mg/g. [ABSTRACT FROM AUTHOR]

The environment contains numerous chemical pollutants from natural processes and human activities, including pesticides, pharmaceuticals, and industrial chemicals. Specifically, the issue of hexavalent chromium water pollution, whether from natural or industrial sources, remains a global and unresolved threat. Hence, there is a need for efficient and prompt monitoring of Cr(VI) concentration in water to determine the potential danger and to facilitate the development of efficient remediation strategies. In this work, the metal-organic framework (MOF) UiO-66-NH 2 was immobilized into poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) polymeric membranes, manufactured in different morphologies, to act as Cr(VI) sorbent to develop a novel portable, easily reactivable, and reusable water filtering and sensing technology. The multifunctional membranes demonstrated an adsorption capacity of 2.32 mg/L in 300 minutes for plasma electrospun-oriented fiber membranes with 10 % w/v of MOFs. The most efficient morphology was selected and integrated into a portable system for simultaneous detection and adsorption in a short time. It shows approximately 50 % adsorption efficiency and a colorimetric sensitivity with an excellent determination coefficient R2 of 0.990, even for very low concentrations at 0.085 ppm. To the best of our knowledge, this work presents the first system that utilizes multi-structured active materials for the remediation and monitoring of an aquatic contaminant. [Display omitted] • Novel multifunctional membranes for simultaneous Cr(VI) water sensing & remediation. • Portable technology which can detects & filters chromium without external equipment. • MOFs and surface plasma treatments enhances hydrophilicity and Cr(VI) adsorption. • Hybrid MOF-polymers with plasma treatment remove 98.85 % Cr(VI). • Groundbreaking integration of colorimetric detection and advanced filtration. [ABSTRACT FROM AUTHOR]

This study evaluates the effectiveness of coupling solar photo-Fenton (SPF) with granular activated carbon (GAC) filtration to remove three selected micropollutants (benzotriazole, carbamazepine and diclofenac) from municipal wastewater treatment plant (WWTP) effluent. SPF was first studied stand-alone at natural pH with simulated and real irradiation in raceway pond reactors (RPR) in different water matrices. The scenario with the poorest removal was the use of real WWTP effluent as water matrix; the removal achieved was 25 % of benzotriazole, 57 % of carbamazepine and up to 80 % of diclofenac (6 mg L−1 of iron, 40 mg L−1 of H 2 O 2 , 15 cm depth, 0.49 kJ L−1). In the second phase, fresh and regenerated GAC were studied in different water matrices, showing that the complex matrices had a higher influence on the regenerated GAC. Thus, the breakthrough of regenerated GAC was achieved quicker than fresh GAC. The aim of the work was to extend the GAC lifetime by a pre-oxidation process; thus, SPF was applied for 5 minutes (0.05–0.08 kJ L−1) as a first step. GAC lifetime was extended between 2 and 12 times thanks to the pre-treatment by SPF, equaling the lifetime of the regenerated GAC to the fresh one in the more complex matrix. [Display omitted] • A pre-oxidation step with SPF can improve performance and applicability of GAC. • The role of chelating agent molar ratio is dominant if compared to iron dosage. • Regenerated GAC is more vulnerable to water matrix composition. • When combined to SPF, regenerated GAC lifetime is similar to the fresh one. • 5 minutes of SPF as pre-step can increase up to 12 times the GAC lifetime. [ABSTRACT FROM AUTHOR]

The function of surface acidity in catalytic reactions has been well studied in the field of conventional catalysis, nevertheless, regulating surface acidic sites and unveiling its roles during heterogeneous photocatalysis has been less frequently reported. To address this issue, we constructed a novel heterojunction photocatalyst of ZnO/SiW 11 Co with abundant Lewis acid sites for wastewater treatment. Under visible light irradiation, the optimal ZnO/SiW 11 Co was found to have the highest photocatalytic activity, achieving a degradation efficiency of 97.7% for Rhodamine B (RhB), 96.1% for tetracycline (TC), and 91.4% for methyl orange (MO). The RhB removal rate remained at 91.3% even after five cycles, indicating excellent stability and practicality of ZnO/SiW 11 Co. By compositing with SiW 11 Co, a typical polyoxometalates with unique super acid properties, ZnO/SiW 11 Co formed plentiful surface Lewis acid sites, as confirmed by the pyridine adsorption FT-IR and NH 3 -TPD. The as-formed Lewis acid sites could provide more active sites, making it easier for reactants to coordinate to the photocatalyst surface, which reduced the activation energy of photocatalytic reactions and accelerate RhB removal. Density functional theory (DFT) calculations unveiled the redistribution of electron-hole pairs, optimizing the light absorption and charge separation efficiency, which obeyed a Z-scheme mechanism. Combined active species capture experiments and electron spin resonance, •O 2 −, h+, and •OH were the main active substances for the photocatalytic degradation of RhB. Besides, the possible degradation pathways for RhB were analyzed using liquid chromatography-mass spectrometry (LC-MS). The work provided useful strategy for the design of high-performance photocatalysts via regulating surface Lewis acid sites toward water remediation. [Display omitted] • A novel ZnO/SiW 11 Co photocatalyst is constructed with abundant Lewis acid sites. • Pivotal role of Lewis acid site is unveiled on enhanced photocatalytic activity. • Construction of Z-scheme heterojunction redistributed the electron-hole pairs. • The photocatalytic degradation pathway of RhB was rationalized using LC-MS. [ABSTRACT FROM AUTHOR]

The water issue has emerged as a significant concern in the current century, mostly attributed to the exponential rise of the worldwide population and the process of globalization. Nanoscience and nanotechnology have emerged as crucial tools in effectively tackling a diverse array of water pollution challenges through the implementation of innovative and efficacious remedies. There has been a significant amount of attention given to the identification and management of new chemical pollutants in recent times. Consequently, it is desired to have dependable and expeditious analytical instruments that possess the capability to conduct sample analysis with heightened sensitivity, extensive selectivity, desirable durability, and less sample manipulation for the identification, breakdown, and elimination of perilous pollutants. This review examines the several gold–carbon nanocomposites-based systems that have been established to date. This paper examines the chemical functionalization of gold-carbon nanocomposites, focusing on its role in providing stable platforms, enabling different applications, and facilitating effective monitoring of water contaminants. The present study discusses the challenges faced in previous research and the potential future utilization of gold-carbon nanocomposites in prognostic sampling for real-time assessment of water quality. This approach offers a promising avenue for addressing the global water issue. [Display omitted] • GNP-carbon composite has emerged as superior nanomaterial in water remediation. • New insights of chemistry between GNP-carbon nano-entities are presented. • Combined physiochemical effects of GNP-carbon influence water recycling metabolism. • Research focus on GNP-carbon nanocomposite at diverse facets for water remediation. • Hurdles encountered and future preference with water remediation are presented. [ABSTRACT FROM AUTHOR]

With the growth of industry and agriculture, contaminants such as pharmaceuticals, pesticides, phenolic residues, heavy metals, among others, have been caused serious pollution of water bodies and soil, so it is very urgently needed to find highly efficacious and cost-effective materials to remove these pollutants from environment. Owing to their low molecular weight, not easily degraded and long-term presence in the aquatic environment, super-stable mineralization effect, easily modifiable surfaces, and anion intercalation properties, molecular imprinted polymers (MIPs) present unique advantages in the removal of emerging pollutants. It is very critical to understand the mechanism of pharmaceuticals, pesticides, phenolic residues, dyes, and heavy metals removal by MIPs for the subsequent design of the adsorbent and photodegradation materials structure. Herein, we discuss the recent advancements in the applications of MIPs in water treatment, with a major focus on their use in adsorption and photocatalysis. The preparation methods and characterization of MIPs intended for water treatment are discussed at the beginning of this review. Then it discusses the potential of MIPs-based nanocomposites for the selective photocatalytic degradation and adsorption of a wide range of pollutants in water. Finally, a summary and the ongoing research efforts in this field is further provided. [Display omitted] [ABSTRACT FROM AUTHOR]

The integration of peroxymonosulfate (PMS) activation and photocatalysis is an effective advanced oxidation technology for the degradation of water pollutants. In this study, iron phthalocyanine (FePc) is successfully loaded onto O-doped porous carbon nitride (OCN) forming a catalyst working in photo-assisted PMS activation. OCN is a metal-free light absorber with strong visible light absorption, while FePc could serve as a photosensitizer and PMS activator. At the same time, the construction of FePc/OCN heterojunction can form the strong internal electric field for charge migration between FePc and OCN. As a result, complete tetracycline (TC) removal within 30 min can be achieved over optimal FePc/OCN catalyst in the presence of light and PMS. Systematic controlled experiments were also carried out to reveal the effect of pH, anion, and aqueous matrix. Cyclic stability test and Fe leaching experiments indicate that the synthesized FePc/OCN is relatively stable and shows the potential in practical application. Furthermore, a comprehensive investigation was conducted on the reactive species generated during the reaction process as well as the degradation pathways of the target pollutants. This work aims to provide new insights into the design of efficient catalysts for photo-assisted PMS activation. [Display omitted] • FePc/OCN is reported for photo-assisted PMS activation reaction. • Nearly 100% TC can be decomposed using FePc/OCN in the presence of PMS and light. • The origin for highly efficient performance is explored systematically. [ABSTRACT FROM AUTHOR]

Citalopram (CIT) is a drug widely used around the world in the treatment of depression. Due to the high toxicity of CIT and the failure of the methods used in treatment plants to purify water, the removal of this pollutant from the environment is very necessary. In this study, the removal of CIT was performed using graphene oxide (GO) and magnetic graphene oxide (GO·Fe 3 O 4 1:1, 1:5, and 1:10). Moreover, the adsorption of CIT was accomplished at low drug concentrations, and the safety of biological and phytological adsorbents was investigated. The characteristics of the adsorbents were analyzed through SEM and TEM images, XRD, EDS, XPS, FTIR, Raman, VSM and the analysis revealed the spectra and signal characteristics of GO and GO·Fe 3 O 4. The GO·Fe 3 O 4 1:1 showed the highest adsorption capacity of 97.92 mg g−1 and removal percentage (98%). The pH, initial concentration, and glucose natural organic matter did not significantly affect the adsorption. The ionic strength and high dosages of GO·Fe 3 O 4 1:1 disfavors the adsorption. Pseudo-second-order (PSO) and Liu models suggest that adsorption occurs at heterogeneous surfaces. The thermodynamic study confirms that CIT adsorption onto GO·Fe 3 O 4 was spontaneous and exothermic. The in vitro assays evidenced that the complex, after adsorption, decreases the genotoxicity and the oxidative stress caused by CIT. Finally, the complex after adsorption does not show phytotoxic for L. sativa seeds. These findings have significant relevance for the safe use of GO·Fe 3 O 4 1:1, allowing the employ in water remediation processes and their biocompatibility for biological applications. [Display omitted] • GO·Fe 3 O 4 1:1 was efficient for the Citalopram adsorption even at low concentrations. • The nanocomposite shows easy operation, eliminating filtration/centrifugation steps. • Post-adsorption complex exhibited biocompatibility with BV-2 and VERO cells line. • Post-adsorption complex promotes the lettuce seed growth. [ABSTRACT FROM AUTHOR]

The performances of FoamFlex200 (TEST-1 SB S.r.l.), an innovative material based on flexible polyurethane foam, have been tested through laboratory and tank tests for the purpose of oil removal in case of oil spill and water treatment. The possibility of reusing this material after regeneration via manual squeezing or by means of a suitable equipment was also evaluated. By way of comparison, the same experimental tests were conducted using polypropylene (PP) flakes, the material currently most used to cope with spill accidents. To better understand the hydrophobic oleophilic properties of the new material, and its application performance, it was tested with oils having different chemical and physical properties, in particular kerosene, diesel, and crude oil. From the laboratory tests, the capacity of FoamFlex200 to retain oil was found to be directly proportional to the viscosity of the latter. Sorption values detected range from 23.2 ± 1.4 g/g for crude oil and 18.8 ± 1.2 g/g for diesel to 8.8 ± 0.6 g/g for kerosene, confirming the potential of the innovative material compared to the PP. Cyclical use/regeneration tests were also performed, showing a high reusability of the material (up to 200 times according to the manufacturer's declaration), with only a slight sorbent capacity decrease in cycles after the first one. Finally, some considerations based on the sorption capacities found were drawn, suggesting the adoption of the new material as also economically preferable, with relevant savings per kg of hydrocarbon treated ranging from 20% to 40% up to a maximum of 94% in the limit of 200 uses. In addition to these savings, the possibility of recovering sorbed oils represents another important advantage, both in economic and environmental terms. • Oil spills are difficult to properly manage in an economic and ecofriendly way. • Using suitable materials is a simple way to confine and address the problem. • Absorbency, selectivity, and reusability are key aspects of material efficiency. • The novel material shows improved performance in all the key aspects mentioned. • Recovering and reusing the adsorbed oil is an added economic and environmental benefit. [ABSTRACT FROM AUTHOR]

Abstract In this study, the sorption properties of a ligno-cellulosic substrate derived from wheat bran, an agricultural by-product, were investigated in order to test its ability to remove enrofloxacin fluoroquinolone antibiotic from water. The influence of contact time, pH and concentration was studied. The pH value played an important role in the adsorption process, evidencing different sorption processes as a function of pH. The results showed that the substrate removed 100% of enrofloxacin at pH 6 in less than one hour and more than 80% above pH 4. Three kinetic (pseudo-first order, pseudo-second order and intra-particle diffusion) and three isotherm (Langmuir, Freundlich and Sips) models were tested at pH 3.7 and 6. The kinetics followed the pseudo second-order model at both pH with a higher constant rate k 2 at higher pH (3.88 g mg−1 h−1 at pH 6). The slower kinetics at pH 3.7 was due to intra-particle diffusion. The isotherm best fit obtained with Sips model indicated a heterogeneous monolayer adsorption of the antibiotic with a high maximum adsorption capacity of 91.5 mg g−1 at pH 6. The tested ligno-cellulosic substrate has emerged as a very good low-cost candidate for enrofloxacin adsorption both in terms of adsorbed amounts and of adsorption kinetics, compared to other adsorbents proposed for enrofloxacin removal. [ABSTRACT FROM AUTHOR]

The elimination and immobilization of contaminants into water bodies have posed an unprecedented threat to the environment, which has significantly increased the demand for freshwater and sparked a plethora of developments toward water sustainability. Metal-organic frameworks (MOFs) have attracted significant interest among the materials being researched for water treatment as potential candidates for the liquid-phase adsorptive elimination of emerging contaminants. However, the crystalline or powdered form of MOFs severely restricts their use due to their innate fragility, poor processability, and low recoverability. Nevertheless, it is increasingly evident that efforts are being undertaken to give MOFs the ability to be shaped at the macroscopic level, which has led to the inclusion of MOFs into hydrogels to generate spherical beads of MOF@hydrogel composite in order to render them for realistic wastewater remediation. The subsequent MOF@hydrogel composite beads (MOF@HG CBs) encompass the application of MOFs in the removal of contaminants by elevating their mechanical flexibility and imparting them superior adsorption characteristics without hampering their adsorptive performance. The present review spotlights the recent advancements in the performance of MOF@HG CBs as adsorbents for the efficacious elimination of heavy metal ions, dyes, pharmaceuticals, personal care items, pesticides, rare earth elements, and organic contaminants. This review will provide basic and in-depth insight to the researchers to explore the advanced undiscovered potential of these adsorbents. [Display omitted] • Versatility and advantages of MOF@HG CBs in wastewater treatment. • Synergistic effects leading to superior adsorption performance have been elaborated. • Adsorption capacity, mechanism and recyclability of MOF@HG CBs are discussed. • Challenges and future perspectives for practical applications are summarized. [ABSTRACT FROM AUTHOR]

Interactions between polymers and different metal ions represent an interesting field of study due their potential use for wastewater remediation. In turn, polymers with technological applications can be obtained from renewable raw materials. In this work, polyesters weighing 2822 Da were obtained from the reaction of an epoxidized biodiesel from sunflower oil. The polyesters were reacted with aqueous sodium hydroxide solutions to obtain polyelectrolytes. The polyelectrolytes were characterized with respect to their structure by Nuclear Magnetic Resonance Spectroscopy, Infrared Fourier Transform Spectroscopy and Gel Permeation Chromatography; their physicochemical behavior in aqueous media as well as their capacity to remove copper ions were characterized by electrical conductivity (EC) and Static and Dynamic Light Scattering measurements (SLS and DLS). The critical aggregation concentration (CAC) was 1.3 × 10 −1 g L −1 polyelectrolyte derived from sunflower oil (PESFO). The polyelectrolyte’s EC abruptly increased when the PESFO concentration increased above the CAC. PESFO in ionic aqueous media developed a rigid rod morphology and had a strong interaction with water and ions (up to 5.1 g L −1 ). Its capacity to remove copper(II) ions from aqueous media was determined, and the interactions between Cu/PESFO were characterized by FTIR. The polyelectrolyte removed up to 35 mg Cu(II)/g PESFO. [ABSTRACT FROM AUTHOR]

This study presents the adsorption capability of a filter composed of sand coated with cobalt nanomaterials (CoNM) for the extraction of manganese ions from aqueous media. The study was performed in both batch and dynamic modes in order to evaluate the adsorption capabilities of free-standing CoNM and CoNM-coated sand. The Langmuir and Freundlich isotherm models were applied to the adsorption of manganese ions in batch-mode. The Langmuir model estimated a maximum adsorption capacity of 17.86 mg/g corresponding to a single layer adsorption. Nevertheless, the Freundlich model also characterized the adsorption with a high coefficient of determination, suggesting a multilayered adsorption mechanism of Mn on CoNM. Dynamic mode studies were conducted with different influent Mn concentrations, pH and in the presence of foreign or competing ions (Fe3+, As3+, As5+ and Cu2+). The experimental data was fitted with linearized Thomas and Yoon-Nelson models in order to determine adsorption capacities. The multilayered adsorption mechanism was confirmed owing to a high adsorption capacity of 3360 mg/g of active nanomaterials at pH = 6. • Magnetic extraction of manganese ions using superparamagnetic cobalt metal nanoparticles. • Langmuir and Freundlich isotherm models applied to the adsorption of manganese ions in batch-mode. • Dynamic mode studies of the extraction of manganese ions fitted with linearized Thomas and Yoon-Nelson models to assess the adsorption capacity. • Study of the influence concentration, pH and competing ions on the adsorption capacity of the nanocomposite. [ABSTRACT FROM AUTHOR]

Wastewater remediation and pollutants removal, such as organic pollutants and heavy metals, have become increasingly important for the protection of environment. Numerous technologies, such as adsorption, membrane separation and photocatalysis, have been proposed to solve this problem. However, these methods also have some disadvantages, such as the inability to mineralize the pollutants during the adsorption process and the serious membrane fouling. Therefore, g-C 3 N 4 as a photocatalyst has been widely used to remove pollutants from wastewater due to graphitic like structure, adjustable morphology, low cost, facile preparation and high chemical stability. However, the pristine g-C 3 N 4 suffers from issues such as small specific surface area, low utilization of visible light and serious photogenerated carrier recombination. Hence, various modification strategies, such as doping, defects, morphology control, metal deposition and heterojunction construction, have been developed to improve its photocatalytic activity. In this review, the synthesis and modification techniques of novel g-C 3 N 4 materials were systematically introduced. Their application and related mechanisms in wastewater remediation and pollutant removal were discussed. Their efficiency, limitations and advantages were also compared and discussed. Furthermore, the promising perspectives and the potential directions of g-C 3 N 4 -based materials in environmental applications were put forward and discussed. In the future, materials modifications through supramolecular self-assembly method and S-scheme heterojunction structure still need to be further explored. And it is of great significance for industrial applications to design new processes that are conducive to material recovery and simultaneous treatment of multiple pollutants. [Display omitted] • The synthesis process and limitations of pristine g-C 3 N 4 are discussed. • The modification strategies of pristine g-C 3 N 4 and influence mechanism were introduced in detail. • The applications and related mechanisms of g-C 3 N 4 -based materials to remove pollutants from wastewater were discussed. [ABSTRACT FROM AUTHOR]

The adsorption efficiency of Zeolites Y (FAU-type topology) with different silica/alumina ratio towards perfluorooctanoic acid (PFOA, C 8 HF 15 O 2) and perfluorooctane sulfonate (PFOS, C 8 F 17 SO 3 H), was investigated by combining batch adsorption and synchrotron X-ray powder diffraction (XRPD) analyses. Adsorption isotherms show that the saturation capacity of Y390 as-synthesized and Ag-exchanged sample, was for PFOA was ~43% and ~62%, and for PFOS was ~17% and ~32% in weight respectively. XRPD Rietveld refinements provided the exact location of PFOA and PFOS in the zeolites network before and after functionalization with Ag. PFAS are located at the center of the supercage, H- bonded to both co-adsorbed water molecules and framework oxygen atoms. Y-PFOA/PFOS and AgY-PFOA/PFOS oligomers strongly interact with oxygen atoms of the zeolite framework, thus immobilizing the pollutants in the zeolite microporosity. These findings indicated that these materials can be successfully used for the decontamination of water from perfluoroalkyl chemicals. Additionally, introduction of Ag onto zeolites could confer combined antifouling and adsorption properties thus exhibiting improved performances compared to zeolite as single compounds thus working synergistically in removal of PFAS from water. [Display omitted] • Y zeolites with different (SAR) were investigated for PFAS adsorption. • Adsorbent materials characterized by chromatographic and diffractometric methods. • Silver in functionalized zeolite does not compete with adsorption sites. • PFOA and PFOS molecules were embedded in the Y zeolite supercage. • Both hydrophobic and electrostatic interactions work synergically. [ABSTRACT FROM AUTHOR]

Zeolitic imidazolate framework-67 (ZIF-67), which consists of metal ions Co2+ and 2-methylimidazole ligand, is a kind of typical MOF material. As an emerging multifunctional material, ZIF-67-based materials have attracted increasing interest in the synthesis and applications due to their exceptionally high surface area, tunable porosity, and excellent thermal & chemical stability. In this paper, we focus on its developments in the field of persulfate advanced oxidation processes (PS-AOPs) for water purification. This review summarizes the latest enhanced strategies of ZIF-67-based catalysts for PS-AOPs, like the construction of immobilized ZIF-67, the functional group combination, metal ion doping, and calcination or sulfuration to produce corresponding derivatives. Finally, we attempt to provide the mechanistic insight for the applications of ZIF-67-based materials in organic wastewater treatment by PS-AOPs and to present the future direction for the application in PS-AOPs of ZIF-67-based materials. [Display omitted] • The PS-AOPs for water treatment adopting ZIF-67-based catalysts were summarized. • The corresponding syntheses, performances and mechanisms of were highlighted. • The prospects and challenges of ZIF-67-based PS-AOPs were proposed and outlooked. [ABSTRACT FROM AUTHOR]

Estrogenic hormones at significant levels are a serious cause of fish femininity, breast and ovarian cancer as a consequence of hormonal imbalance. This study reports the fabrication of electrospun polyurethane (PU) nanofibers modified by coating with polyaniline/polyvinyl alcohol (PANI/PVA) to form filtration membranes for the enhanced removal of ethinylestradiol (EE2) estrogenic hormone. Structural and morphological characterization was performed by FTIR, SEM and optical microscopy, while the detection and quantification of EE2 were analysed using HPLC. To understand the material characteristics, the feasibility of the results based on contact time and kinetics to determine the adsorption capacity coated PU nanofibers was further investigated. Findings demonstrated that EE2 best fitted pseudo-second-order kinetics. Furthermore, the adsorption process was optimised via response surface methodology using a central composite design model by varying parameters such as pH, temperature, the concentration of adsorbate, and adsorbent dosage to determine. It was found that the modified PU membranes had a maximum adsorption capacity of 2.11 mg/g and high removal percentage efficiency of ~82.20% for EE2. Adsorption mechanism and thermodynamics were also evaluated, and the results depicted the adsorption process of EE2 occurred via intraparticle diffusion and was exothermic in nature. Finally, a reusability study was done over six adsorption-desorption cycles to test the consistent effectiveness of the modified PU membrane, which remained above 80% removal capacity. Overall, the findings indicate that treated PU with stabilized PANI particles possess the potential to form an effective adsorbent for eradicating EE2 and other estrogenic hormones from the environment. [Display omitted] • Coated spun PU membranes were prepared by incorporating PANI via an in situ polymerization process. • Hormone adsorption by different coated PU-PANI membranes was evaluated. • High surface functionality of PU-PANI membranes lead to improve adsorption of hormone. • Adsorptive interactions parameters were investigated by optimization study. • PU-PANI-ES showed fast adsorption kinetics and highest removal capacity. [ABSTRACT FROM AUTHOR]

Hierarchically porous carbon (HPC) has exhibited exceptional performance in environmental-related applications; however, the synthesis of high-efficient biobased HPCs remains a challenge because of the inherent structure and chemical composition complexities of biomass. Here, we prepare high-efficient biobased HPC sorbents featuring uniform micron-sized (~20 µm) honeycomb cells and abundant meso- and micropores through combining the selection of biomass precursors and the corresponding synthetic strategies. Cork is selected as the precursor because of its distinctive hollow polyhedral cellular structure and unique chemical composition composed of suberin. ZnCl 2 is selected as the activation reagent due to its mild activation effect with less carbon etching and recyclability. The sequential low-temperature pretreatment and ZnCl 2 activation processes produce high-efficient HPC sorbent for CO 2 capture and water decontamination. Results show that cork-based HPC poses high carbon yield (> 80 wt%), large specific surface area (up to 1853 m2/g), and high pore volume (up to 0.839 cm3/g). Accordingly, cork-based HPC exhibit high CO 2 capture performance (e.g., 4.64 mmol/g at 0 °C), superior adsorption capacity for methylene blue (887.7 mg/g) and lead ion (Pb2+, 74.3 mg/g), and fast uptake speed for contaminants (i.e., < 5 min). Moreover, approximately 80% of ZnCl 2 can be recycled and reused. This study demonstrates a sustainable and cost-effective process for producing high-efficient HPCs from cork for environmental applications. [Display omitted] • Biobased hierarchically porous carbon (HPC) featuring ~20 µm honeycomb cells is produced. • HPC is synthesized from low-temperature ZnCl 2 activation of cork dust. • HPC poses high adsorption capacities for CO 2 , methylene blue and Pb(II). • ZnCl 2 is recyclable and reusable [ABSTRACT FROM AUTHOR]

Three carbon materials from a varied origin, composition and porosity have been used as cost-effective cathodes in different electrochemical advanced oxidation processes (i.e. anodic oxidation (AO) and electro-Fenton (EF) in homogeneous and heterogeneous catalysis modalities) for the degradation of an antibiotic (e.g., metronidazole). In general, the efficiency towards the pollutant degradation increased as: AO < homogeneous EF < heterogeneous EF. The heterogeneous EF approach with iron pre-loaded in the carbon cathode outperformed the homogenous EF counterpart, despite a lower amount of iron. Reusability tests showed that iron-containing cathodes prepared from samples CQ (carbon obtained upon steam activation) and CB (carbon prepared by H 3 PO 4 activation of biomass) were stable over at least three consecutive cycles. The best results were attained for cathode prepared with carbon CQ modified with iron, yielding over 97% removal of metronidazole after 150 min in all three reuses. Such better performance is related to the favorable adsorption of the pollutant on carbon CQ, thereby favoring the close contact between the generated oxidant species and the target antibiotic. The cathode based on carbon CQ was tested for the degradation of another recalcitrant antibiotic (sulfamethoxazole) in a real wastewater treatment plant effluent by means of a heterogeneous EF treatment, showing good degradation performance. [Display omitted] • Cost-effective carbon-based cathodes were elaborated from varied carbons. • Cathodes were tested for antibiotics removal in anodic oxidation and electro-Fenton. • Heterogeneous electro-Fenton (Fe-loaded cathodes) showed the best performance. • Degradation of metronidazole and sulfamethoxazole from synthetic and real waters. • Carboxylic acids and nitrates indicated a partial mineralization of the antibiotics. [ABSTRACT FROM AUTHOR]

Remediation of cadmium ion in polluted water suffers from high cost and low efficiency. Nanoscale zero-valent iron (NZVI) was able to extract Cd(II) from water effectively, but the liability to aggregate greatly limits its broad application. Herein, we develop a promising remedy (CCP@NZVI) for the rapid and efficient removal of Cd(II) in water by facile coating conductive carbon paint (CCP) on NZVI. Compared with NZVI alone, CCP@NZVI shows enhanced efficiency, achieving removal up to 95% in 5 min at a low dose (0.67 g/L). We demonstrated the validity of a build-in primary battery as the driving force for the removal of Cd(II). In water contaminated by Cd(II), NZVI acting as the anode tends to be oxidized to ferrous ion and transfers electron to CCP as the cathode, wherein dissolved O 2 is reduced to OH- for interfacial Cd(II) precipitation. A panel of characterization techniques including scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray powder diffraction, and open circuit potential, have been used to analyze CCP@NZVI before and after the reactions, verifying the immobilization of absorbed Cd(II) in CCP@NZVI as Cd(OH) 2. In addition, this method exhibits good stability against weak acid and coexisting anions with satisfactory biosafety. Importantly, the Cd-immobilized CCP@NZVI after treatment can be easily separated via weak magnetic field. This study provides a novel strategy to achieve rapid Cd(II) removal at low-cost and with collectability, which may have a tremendous application prospect in environment fields including water treatment and soil detoxication. [Display omitted] • A primary battery nanosystem was fabricated. • Core-shell structured CCP@NZVI consists of NZVI and conductive carbon paint (CCP). • CCP@NZVI could effectively remove Cd(II) from water rapidly. • CCP@NZVI after treatment can be readily separated from water by magnet. • CCP@NZVI possessed a good biosafety. [ABSTRACT FROM AUTHOR]

Developing superior adsorbents to remove pollutants from aqueous solution is increasingly becoming urgent with respect to grave water pollution and public health consequences. Herein, a metal organic framework (MOFs)-decorated shapeable aerogel (CS-CNC@UiO-66-NH 2) prepared by in situ growth of Zr-MOF (UiO-66-NH 2) on chitosan/cellulose nanocrystal (CS-CNC) hybrid aerogel at room temperature was developed to remove glyphosate (Gly) from water. The aerogel possessed highly porous structure and excellent water stability upon introduction of cellulose nanocrystals extracted from cotton. Besides, the loading ratio of UiO-66-NH 2 of the proposed ambient growth strategy (37.72%) was higher than conventional solvothermal method (10.91%) because of the structure integrity of polysaccharide aerogels at room temperature. Further, the BET area and porosity of CS-CNC@UiO-66-NH 2 aerogel increased from 21.65 m2 g−1 to 231.60 m2 g−1 and 87.47–93.03% due to the synergy of UiO-66-NH 2. Owing to these virtues, the separation-free aerogel exhibited a high adsorption capacity of 133.7 mg/g in batch adsorption and displayed high recyclability over four consecutive adsorption-desorption cycles. Moreover, the Zr-OH/oxygen-containing moieties of the aerogel, electrostatic attraction and hydrogen-bonding accounted for driving Gly adsorption. Considering practical application, the aerogels were packed in glass column for fixed-bed test which revealed that the aerogels could decontaminate Gly with column adsorption capacity of 44.99 mg/g. Consequently, the CS-CNC@UiO-66-NH 2 aerogel with highly porous structure exhibited good Gly adsorption and simple separation, offering a novel strategy to synchronously improve adsorption capacity of polysaccharide-based adsorbent and MOFs shaping for pollutant removal. [Display omitted] • Synchronously improving adsorption of polysaccharide adsorbent and shaping of MOFs. • High UiO-66-NH 2 loading polysaccharide aerogel prepared by ambient growth. • Cellulose nanocrystal endowed highly porous structure and enhanced water stability. • Enhanced adsorption due to porous structure of aerogel and high porosity of MOFs. • Facile separation and recyclability of the aerogel adsorbent after adsorption. [ABSTRACT FROM AUTHOR]

This review study summarizes relevant topics about the photoelectrocatalytic semiconductors for the degradation of organic pollutants. Among the topics are A) the basic concepts of photocatalysis and photoelectrocatalysis for the advanced oxidation of organics in water. B) The band theory about heterojunctions, Schottky barriers, and doping of these semiconductors being photocatalysts. C) Proposing the outlook for photocatalysts, as those systems arranging doped semiconductors with heterojunctions and having Schottky junctions, a set of tables and sections show reported cases that complement the semiconductor characteristics providing the percentage of degradation attained, such as photoanodes of Boron-doped TiO 2 nanotubes, TiO 2 - Sb 2 S 3 composites, and so forth. D) The novel characteristics of graphene-based materials for improving photoelectrocatalytic systems. E) A systematic way of classifying and understanding photoelectrocatalytic semiconductors based on their relevant characteristics and photoelectrochemical mechanisms. Moreover, this work shows the photoelectrocatalytic properties of the recently reported graphene oxide - reduced graphene oxide (GO-rGO) nanohybrids, which can also be used for the degradation of organic pollutants. Finally, based on all the previously gathered and summarized information, some inferences are made about the photoelectrocatalytic properties of some GO-rGO based heterojunctions for the degradation of organic pollutants. [Display omitted] • Semiconductor properties affecting PEC production of hydroxyl radicals. • Types of photoelectrocatalytic semiconductors for production of hydroxyl radicals. • State of the art and prospects of PEC semiconductors for water treatment. • The outlook are doped photocatalysts having heterojunctions and Schottky barriers. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA) is a noteworthy and ubiquitous chemical of concern. Up to this day, several methods of water remediation have already been tested, however, few studies have addressed the fixed-bed adsorption of this contaminant. In this regard, this work aimed to evaluate the continuous adsorption of BPA using an organoclay (Spectrogel® type-C) as an adsorbent. The material passed through a series of characterisation techniques to elucidate the impact of the contaminant uptake onto the organoclay. The effect of the operation conditions on the adsorption behaviour was evaluated through breakthrough curves and the calculation of mass transfer and efficiency parameters The system conducted at 0.6 mL min−1 and 0.2 mmol L−1 obtained the highest removal (95%) until breakthrough point (19.29 h), as well as greater breakthrough and exhaustion adsorption capacities (0.0424 and 0.2151 mmol g−1, respectively). The breakthrough curves were correlated by five distinctive models and the modified dose response model showed the finest fitting to the data (R2 > 0.97). Furthermore, the regeneration potential of the spent adsorbent was investigated. It was observed that NaOH solution was a satisfactory eluent. Moreover, density functional theory (DFT) calculations were studied to give further insights regarding BPA adsorption. [Display omitted] • Fixed-bed adsorption of Bisphenol A onto organoclay was successfully performed. • Useful and total adsorption capacities were 0.04 and 0.21 mmol/g, respectively. • Modified dose-response model better described the breakthrough curve data. • The regeneration potential of spent organoclay was studied. • DFT-based chemical quantum descriptors were calculated. [ABSTRACT FROM AUTHOR]

Oil-contaminated water has become a severe threat to the environment, human and aquatic life. The major contributor to oil pollution is the periodical oil spill incidents and the oily effluents released from the industry. For efficient separation and recovery of oil from contaminated water, selective wettable surfaces have received substantial attention. However, high cost, compromised efficiencies, and complex preparation methods are the significant challenges in developing selective wettable membranes. A scalable approach is adopted to develop a highly selective super-wettable/superhydrophobic mesh for oil/water separation. The surface chemistry of the mesh membrane was controlled by surface activation (SA) and chemical functionalization with 3-[2-(2-Aminoethylamino)ethylamino]propyl-trimethoxysilane (TAS) and palmitic acid. The SEM and FTIR analysis have revealed the successful functionalization with the TAS and PA. SSM's functionalized surface has appeared super-selective for oil with a water contact angle of 161°. The surface attached-detached analysis has shown that water drops have no affinity to the functionalized mesh. During oil/water separation, the surface has selectively separated the oil from water under the force of gravity with a separation efficiency of up to 98.7%. PA-TAS-SA-SSM has shown the fast permeation of oil during oil/water mixture separation with a flux of 29,161 ± 2169 L m−2 h−1. Due to high flux and excellent separation efficiencies, the developed mesh membrane can be effectively used for oil/water separation. [Display omitted] • A superhydrophobic stainless steel mesh membrane has been developed with a water contact angle of 161°. • The functionalized surface of the mesh membrane has shown good mechanical and chemical stability. • The separation efficiency of the mesh membrane for oil-related contaminants from the water was found up to 98.7%. [ABSTRACT FROM AUTHOR]

We report the preparation of a new hybrid magnetic nanocomposite (HMNC) based on maghemite (γ-Fe 2 O 3), chitosan (Chi), and polypyrrole (PPY), and its use in water remediation protocols. We prepared the γ-Fe 2 O 3 nanoparticles by a coprecipitation route in the presence of chitosan, whose role is to envelop the nanoparticles, easing the posterior incorporation of PPY chains. We characterized the resulting hybrid composites by scanning electron microscopy (SEM), X-ray diffraction (XRD), infrared (FTIR) spectroscopy, water contact angle, and magnetic measurements. The γ-Fe 2 O 3 @Chi@PPY HMNC exhibited spherical morphology, with an average diameter of 34 nm, and a saturation magnetization of 9.8 emu.g−1. Due to this characteristic, these composites can be easily removed through the application of an external magnetic field. The HMNC showed their best capacity of removing Cr (VI) ions from aqueous media at pH 2.0, attaining a 100% degree of capture for concentrations below 10 mg.L−1, with a maximum removal capacity (301.2 mg.g−1) that is higher than those of other polypyrrole based materials discussed in the literature. Recycling studies showed that the HMNC presented excellent performance and could be reused in at least five consecutive adsorption/desorption cycles without significant losses in their original adsorption capacity. For allying high adsorbing characteristics to a simple manner of removal of the captured contaminant from aqueous media, this γ-Fe 2 O 3 @Chi@PPY HMNC appears as a very promising platform for wastewater treatment. ga1 • The combined presence of Chi and PPY leads an increase of the HMNC adsorption capacity. • The magnetic characteristics of the HMNC allow its easy recovery from liquid media. • The HMNC can be recycled and used for five consecutive times. • The HMNC is a promising cost-effective material for the efficient removal of Cr (VI) ions. [ABSTRACT FROM AUTHOR]

• Caffeic Acid adsorption onto ZSM-5 depends on pH. • Caffeic Acid is incorporated into the zeolite framework. • The hydroxyl group of caffeic acid interacts with the framework oxygen atoms. • Competitive adsorption on ZSM-5 follows the order Toluene > Caffeic Acid. Wastewaters and polluted natural water can contain a large variety of organic substances deriving from both natural and anthropogenic sources. Hydrophobic zeolites have great potential for the removal of different organic substances and among them aromatic, chlorinated, and oxygenated compounds. In this work the influence of caffeic acid - an allelochemical representing low molecular weight natural organic matter - on the adsorption of toluene in aqueous matrix has been investigated. To accomplish this task, the adsorption of caffeic acid on ZSM-5 has been studied. Differently from toluene, whose adsorption is not significantly influenced by pH, the uptake of caffeic acid onto zeolite strongly depends on pH, the maximum saturation capacity (46 mg g−1) was obtained at pH 4, corresponding to the nonionized form of caffeic acids. Additionally, caffeic acid interacts with zeolite framework and water molecule as suggested from the shift in the apparent dissociation constant evaluated from adsorption data and confirmed by structural investigation. Competitive adsorption of binary mixture of toluene and caffeic acid in a wide concentration range shows that ZSM-5 is a selective adsorbent for Toluene, and when caffeic acid is present at high concentration (100 mg L−1) the adsorbed quantity of toluene from solution is reduced of less than 15 %. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Vitamins C and L1 were employed as green surface modifiers of nanosilica. • Microwave assisted and mechanochemical preparation approaches. • Microwave-assisted sorption and removal of metals from water samples. • Excellent microwave-assisted sorption capacity values in 15 s. • Langmuir and Freundlich models to evaluate adsorption mechanisms. Abstract In this study, ascorbic acid (vitamin C) and anthranilic acid (vitamin L 1) have been effectively employed as green surface modifiers of nanosilica (NSi) to immobilize and acquire two novel nanosorbents assigned as NSi-Vit C and NSi-Vit L, individually by means of microwave-assisted reactions and mechanochemical blending approaches. The produced nanosorbents were confirmed by instrumental analyses and portrayed to impose good improvement and excellent selectivity in adsorption by microwave heating and removal of Cu(II), Cd(II) and Pb(II) from water samples to illustrate green, quick and sustainable approach. Various factors; microwave-contact time, pH, nanosorbents dose, initial metal ions and competing ions influencing the metal sorption results were investigated. The best characterized adsorption capacities by microwave heating by NSi-Vit C and NSi-Vit L for Cu(II) were 1450 and 1650 μmol g−1 at pH 4 and for Pb(II) were 1550 and 1700 μmol g−1, respectively. Finally, at pH 7 these were 1500 and 1800 μmol g−1 for Cd(II) using 10 mg of nanosorbents at power 800 W for 15 s. The sorption of divalent metals was evaluated with the Langmuir and Freundlich models to demonstrate different adsorption mechanisms. The propposed MW method accomplished quick remedy of Cu(II) with 92.2 and 93.1%, Cd(II) with 94.1 and 97.1% and Pb(II) with 92.9 and 94.3% from tap water utilizing NSi-Vit C and NSi-Vit L. [ABSTRACT FROM AUTHOR]