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Nowadays, there is a global concern over water quality and the impact of contamination on both natural ecosystems and human well-being. Plastics, ubiquitous in modern life, may release harmful chemicals when they reach aquatic environments. Among them, bisphenol A (BPA) and its alternatives, such as bisphenol S (BPS), bisphenol F (BPF), and others, are of special concern because their presence in water systems can have detrimental effects on human health and aquatic organisms due to their endocrine-disrupting properties. This study explores the potential of terpenoids, sustainable and environmentally friendly solvents, for efficiently removing bisphenols from contaminated environmental water. Using an in silico approach based on the Conductor-like Screening Model for Realistic Solvents (COSMO-RS) theory, more than 30 terpenoids were screened, and carvone was found to be an excellent candidate due to its high solvent capacity and low toxicity. The impact of pH, temperature, stirring conditions, and sample:extractant phase ratios on the extraction efficiency were investigated. A design of experiments revealed optimal conditions for the extraction process and demonstrated that carvone can effectively extract bisphenols (nearly 100 % for most of them) under a wide range of conditions, showing the robustness and efficiency of the extraction method, even in environmental samples. The paper provides valuable insights into the potential of terpenoids, specifically carvone, as a sustainable and eco-friendly solvent for removing bisphenol contaminants from environmental water bodies. The findings of this study offer a promising solution to address water contamination issues, aligning with the principles of Green Chemistry and contributing to a more environmentally responsible approach to water remediation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

This work aims to apply carbon quantum dots (CQDs) from agriculture cellulosic waste (agro wastes), produced via an economically and eco-friendly single-step method, to be used into cellulose acetate composite microfibrous membranes as an innovative solution specifically designed to adsorb methylene blue (MB) and other cationic dyes that are present in various water effluents. Batch adsorption tests were conducted, with variations in contact time (1-24 h), initial MB concentration (25-300 ppm), and adsorbent doses (1-20 g/L). The maximum adsorption capacity of the membrane was 198 mg/g with an initial concentration of 300 ppm at 298 K. Thermodynamic parameters showed that the process is endothermic. Equilibrium experimental data for MB adsorption onto electrospun adsorbent were fitted using different isothermal models, with the Freundlich model showing the best fit. The pseudo-second-order model accurately described the kinetic data with high reliability (R 2  > 0.99), and the calculated adsorption capacity was very close to the experimental data. N-CQDs loaded membranes were also tested for removing methyl violet and rhodamine B, demonstrating remarkably high dye removal efficiency. The underlying adsorption mechanism was also reported. Finally, it is worth mentioning that composite adsorbents can be efficiently applied to actual industrial cases because of the possibility of reusing them, opening the route to the fabrication of novel and highly performant adsorbents. These findings underscore N-CQDs' effectiveness in enhancing pollutant removal efficiency from wastewater, highlighting their environmental benefits and promoting a more sustainable approach to water treatment. Therefore, the prepared adsorbent, showing excellent adsorption performance, places them among adsorbents for practical applications in wastewater purification., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

There is an immediate need for meticulous design of easily accessible, cost-effective, chemically stable and eco-friendly materials for effectively removal of water contaminant. Herein, targeting typical water contaminants, endocrine disrupting chemicals (EDCs), three cationic hyper-cross-linked porous polymers (ciHCP-1, ciHCP-2, ciHCP-3) with multiple adsorption sites were designed with 2-hydroxypropyltrimethyl ammonium chloride chitosan (HACC) as precursor. The ciHCP-3 with large surface area (806 m 2  g -1 ) exhibited high sorption capacity (137-366 mg g -1 ), and fast adsorption kinetics (5 min) for the EDCs, which is superior to the reported sorbents. The adsorption mechanisms can be attributed to the synergistic effect of physisorption and chemisorption. The high preparation reproducibility, physicochemical stability, and reuse capability of ciHCP highlights its great potential in practical water remediation applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Most adsorbents are currently restricted by their single function in pollutant removal from complex wastewater. Herein, we constructed a versatile chitosan-based adsorbent (MC-DA) by grafting amphoteric copolymers with high pH-responsiveness property, aiming at the removal of multiple ionic contaminants. Specifically, the surface charge and hydrophobicity/hydrophilicity of MC-DA can be finely tuned under different pH conditions. As a result, the effective adsorption of cationic methylene blue (MB) and anionic Acid Orange 7 (AO7) with capacities of 627.4 mg/g and 1146.8 mg/g were achieved respectively, superior to most reported materials. Regarding the characterization results, the adsorption mechanisms for MB adsorption were electrostatic and hydrophobic interactions, while the electrostatic attraction was the main driving force for AO7 adsorption. Apart from the versatile adsorption performance, high acid resistance (pH ≥ 2.0), good reusability and rapid separation property under an external magnetic field suggested MC-DA's promising environmental benefits and practical application potential in water remediation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Periodate (PI, IO 4 - )-based advanced oxidation processes (AOPs) provide an economical and sustainable approach to alleviate water pollution challenges. Developing efficient and stable activators for PI is the focus of current research. Herein, S/Fe-co-doped magnetic porous carbon material (S/Fe-ZIF-950) was prepared by introducing exogenous S atoms using Fe-doped zeolitic imidazolate framework-8 (Fe-ZIF-8) as a precursor, which showed the most superior performance (100 % within 10 min) in activating PI to remove p-chlorophenol (4-CP). Quenching tests, electron spin resonance and electrochemical characterizations revealed that IO 3 ·, 1 O 2 , ·O 2 - dominated the 4-CP degradation process with Fe 3 C and ZnS as the main active sites. The synergistic effect of S and Fe was the main reason for the enhanced degradation performance of 4-CP in S/Fe-ZIF-950/PI system, among which the reducing S 2- could effectively promote the regeneration of Fe(Ⅱ), thus facilitating the continuous generation of active species. Combined with LC-MS results and density functional theory (DFT) calculations, possible degradation routes of 4-CP in the S/Fe-ZIF-950/PI system were presented. Moreover, toxicity assessment showed that the S/Fe-ZIF-950/PI system exhibited low biotoxicity and no toxic iodine by-products were formed. In addition, S/Fe-ZIF-950/PI system demonstrated excellent activity, good stability, outstanding reusability and durability in a variety of complex water environments. This study investigated the activation mechanism of S/Fe-co-doped porous carbon materials on PI, which shed a new light on the catalytic activation of PI by heteroatom-doped Fe-loaded carbon-based materials., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Capacitive deionization (CDI) offers a cost-effective and low-energy method for selective removal of Pb 2+ from drinking water. Modifying CDI electrode surfaces with functional groups presents a versatile approach to enhancing selective ion adsorption capacity. However, a comprehensive understanding of the selectivity and removal efficiency of Pb 2+ among diverse functional groups remains unexplored. Here, we investigated the effects of different functional groups (-SH, -COOH, and -NH 2 ) attached to the graphene oxide (GO) electrode surfaces on Pb 2+ selectivity and removal efficiency. Surprisingly, GO-COOH demonstrated single-atom adsorption of Pb 2+ , displaying superior removal efficiency and selectivity compared with -SH and -NH 2 , although -SH possesses significant chelation capability for Pb 2+ . Both density functional theory (DFT) calculations and X-ray pair distribution function (PDF) analyses confirmed that Pb 2+ exhibits a theoretically higher affinity to -COOH. This research deepens our understanding of the interactions between functional groups and heavy metal ions, enabling selective and rapid separation of target cations for water purification., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Bisphenol-A (BPA) is an emerging hazardous contaminant, which is ubiquitous in the environment and can cause endocrine disruptor and cancer risks. Therefore, biodegradation of BPA is an essential issue to mitigate the associated human health. In this work, a bacterial strain enables of degrading BPA, named BPA-LRH8 (identified as Xenophilus sp.), was newly isolated from activated sludge and embedded onto walnut shell biochar (WSBC) to form a bio-composite (BCM) for biodegradation of BPA in water. The Langmuir maximum adsorption capacity of BPA by WSBC was 21.7 mg g -1 . The free bacteria of BPA-LRH8 showed high BPA degradation rate (∼100 %) at pH 5-11, while it was lower (＜20 %) at pH 3. The BCM eliminated all BPA (∼100 %) at pH 3-11 and 25-45 °C when the BPA level was ≤ 25 mg L -1 . The spectrometry investigations suggested two possible degradation routes of BPA by Xenophilus sp. In one route, BPA (C 15 H 16 O 3 ) was oxidized to C 15 H 16 O 3 , and then broken into C 9 H 12 O 3 through chain scission. In another route, BPA was likely hydroxylated, oxidized, and cleaved into C 9 H 10 O 4 P 4 , which was further metabolized into CO 2 and H 2 O in the TCA cycle. This study concluded that the novel isolated bacteria (BPA-LRH8) embedded onto WSBC is a promising and new method for the effective removal of BPA and similar hazardous substances from contaminated water under high concentrations and wide range of pH and temperature., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Global water pollution by various pollutants is becoming an urgent problem. The conversion of durian fruit waste into adsorbents can help to mitigate this issue. Transforming durian waste into adsorbents can reduce pollution risk from waste discharged directly into the environment, while also effectively eliminating existing contaminants. Here, this work explores the potential of durian fruit waste and supplies insights into the synthesis and application of durian fruit waste-derived adsorbents such as biosorbents, modified-biosorbents, biochars, activated carbons, and composites. Several factors affecting the adsorption process of pollutants and the mechanism how pollutants can be adsorbed onto durian fruit waste-derived adsorbents are elucidated. This review also analyzes some aspects of limitations and prospects of biosorbents derived from durian fruit waste. It is anticipated that the promising properties and applications of durian fruit waste-derived adsorbents open up a new field for water waste treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

As trace levels of thallium (Tl) in water are lethal to humans and ecosystems, it is essential to exploit advanced technologies for efficient Tl removal. In response to this concern, an innovative composite membrane was developed, incorporating polytetrafluoroethylene (PTFE) and featuring a dual-support system with polydopamine (PDA) and polyethyleneimine (PEI), along with bimetallic Prussian blue analogues (Co@Fe-PBAs) as co-supports. The composite membrane exhibited an exceptional Tl + -adsorption capacity (q m ) of 186.1 mg g -1 when utilized for the treatment of water containing low concentration of Tl + (0.5 mg⋅L -1 ). Transmission electron microscopy displayed the obvious Tl + mapping inside the special hollow Co@Fe-PBAs crystals, demonstrating the deep intercalation of Tl + via ion exchange and diffusion. The Tl + -adsorption capability of the composite membrane was not greatly affected by coexisting Na + , Ca 2+ and Mg 2+ as well as the tricky K + , indicating the excellent anti-interference. Co-doped PBAs enhanced ion exchange and intercalation of the composite membrane with Tl + leading to excellent Tl + removal efficiency. The composite membrane could efficiently remove Tl + from thallium-contaminated river water to meet the USEPA standard. This study provides a cost-effective membrane-based solution for efficient Tl + removal from Tl + -containing wastewater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Environmental electrochemistry and water resource recovery are covered in this review. The study discusses the growing field's scientific basis, methods, and applications, focusing on innovative remediation tactics. Environmental electrochemistry may solve water pollution and extract resources. Electrochemical methods may effectively destroy or convert pollutants. This method targets heavy metals, organic compounds, and emerging water contaminants such as pharmaceuticals and microplastics, making it versatile. Environmental electrochemistry and resource recovery synergize to boost efficiency and sustainability. Innovative electrochemical methods can extract or synthesise metals, nutrients, and energy from wastewater streams, decreasing treatment costs and environmental effect. The study discusses electrocoagulation, electrooxidation, and electrochemical advanced oxidation processes and their mechanics and performance. Additionally, it discusses current electrode materials, reactor designs, and process optimisation tactics to improve efficiency and scalability. Resource recovery in electrochemical remediation methods is also examined for economic and environmental feasibility. Through critical examination of case studies and techno-economic evaluations, it explains the pros and cons of scaling up these integrated techniques. This study covers environmental electrochemistry and resource recovery's fundamental foundations, technology advances, and sustainable water management consequences., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

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 pH PZC . 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., (© 2024. The Author(s).)

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, pH ZPC 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., (© 2024. The Author(s).)

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., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Focusing on the uncontrolled discharge of organic dyes, a known threat to human health and aquatic ecosystems, this work employs a dual-functional catalyst approach, by immobilizing a synthesized bismuth sulfur iodide (BiSI) into a poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) polymeric matrix for multifunctional water remediation. The resulting BiSI@PVDF nanocomposite membrane (NCM), with 20 wt% filler content, maintains a highly porous structure without compromising morphology or thermal properties. Demonstrating efficiency in natural pH conditions, the NCM removes nearly all Rhodamine B (RhB) within 1 h, using a combined sonophotocatalytic process. Langmuir and pseudo-second-order models describe the remediation process, achieving a maximum removal capacity (Q max ) of 72.2 mg/g. In addition, the combined sonophotocatalysis achieved a degradation rate ten and five times higher (0.026 min -1 ) than photocatalysis (0.002 min -1 ) and sonocatalysis (0.010 min -1 ). Furthermore, the NCM exhibits notable reusability over five cycles without efficiency losses and efficiencies always higher than 90%, highlighting its potential for real water matrices. The study underscores the suitability of BiSI@PVDF as a dual-functional catalyst for organic dye degradation, showcasing synergistic adsorption, photocatalysis, and sonocatalysis for water remediation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

In this study, we report on the synthesis of ternary photocatalysts comprising TiO 2 /SnO 2 /g-C 3 N 4 for the degradation of ciprofloxacin (CIP) in water. SnO 2 nanoparticles were synthesized via the sol-gel method, while g-C 3 N 4 was obtained through melamine calcination. Commercial TiO 2 and SnO 2 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, N 2 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-C 3 N 4 (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 TiO 2 /SnO 2 /g-C 3 N 4 for CIP degradation, particularly under solar radiation., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

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., (© 2024. The Author(s).)

Considering the persistent and covert nature of heavy metal soil contamination, the sustainable development of ecological environments and food safety is at significant risk. Our study focuses on remediating soils contaminated with chromium (Cr); we introduce an advanced remediation material, iron oxide phosphoric acid-loaded activated biochar (HFBC), synthesized through pyrolysis. This HFBC displays greater microporosity, fewer impurities, and enhanced efficiency for the remediation process. Our research utilized a comprehensive set of analytical techniques, including Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Photoelectron Spectroscopy (XPS), alongside adsorption studies to elucidate the Cr removal mechanism. The effectiveness of HFBC in remediation was influenced by several factors: the pH level, dosage of HFBC, the initial concentration of Cr, and the ambient temperature. Our results indicated an optimal chromium (VI) adsorption capacity of 55.5 mg/g by HFBC at a pH of 6.0 and a temperature of 25 °C, with the process adhering to the pseudo-second-order kinetic model and the Langmuir adsorption isotherm, thus suggesting spontaneity in the uptake method. Moreover, this mechanism encompasses both adsorption and reduction reactions. Using HFBC in pot experiments with cabbage indicated not only an increase in soil pH and cation exchange capacity (CEC), but also a surge in bacterial community abundance. Significant reductions in bioavailable chromium were also recorded. Interestingly, HFBC addition bolstered the growth of cabbage, while concurrently diminishing chromium accumulation within the plant, particularly notable as the HFBC application rate increased. In summation, the HFBC produced in our study has demonstrated convincing efficacy in removing chromium from aqueous solutions and soil. Moreover, the positive agronomic implications of its use, such as enhanced plant growth and reduced heavy metal uptake by plants, indicate its high potential for operational value in the domain of environmental remediation of heavy metals., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Extracting heavy metal ions from wastewater has significant implications for both environmental remediation and resource preservation. However, the conventional adsorbents still suffer from incomplete ion removal and low utilization efficiency of the recovered metals. Herein, we present an extraction and reutilization method assisted by porous boron nitride (p-BN) containing high-density N atoms for metal recovery with simultaneous catalyst formation. The p-BN exhibits stable and efficient metal adsorption performance, particularly for ultra-trace-level water purification. The distribution coefficients towards Pb 2+ , Cd 2+ , Co 2+ and Fe 3+ can exceed 10 6  mL g -1 and the residual concentrations that reduced from 1 mg L -1 to 0.8-1.3 μg L -1 are much lower than the acceptable limits in drinking water standards of World Health Organization. Meanwhile, the used p-BN after Co ion adsorption can be directly adopted as a high-efficiency catalyst for activating peroxymonosulfate (PMS) in organic pollutant degradation without additional post-treatment, avoiding the secondary metal pollution and the problems of neglected manpower and energy consumption. Moreover, a flow-through multistage utilization system assisted by p-BN/polyvinylidene fluoride (PVDF) membrane is constructed for achieving both metal ion separation and reutilization in the removal of organic pollutants, providing a new avenue for sustainable wastewater remediation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Quiescent batch experiments were conducted to evaluate the influences of Cl - , F - , HCO 3 - , HPO 4 2- ) for water remediation using the methylene blue (MB) method. Strong discoloration of MB indicates high availability of solid iron corrosion products (FeCPs). Tap water was used as an operational reference. Experiments were carried out in graduated test tubes (22 mL) for up to 45 d, using 0.1 g of Fe 4 2- on the reactivity of metallic iron (Fe 0 ) for water remediation using the methylene blue (MB) method. Strong discoloration of MB indicates high availability of solid iron corrosion products (FeCPs). Tap water was used as an operational reference. Experiments were carried out in graduated test tubes (22 mL) for up to 45 d, using 0.1 g of Fe 0 and 0.5 g of sand. Operational parameters investigated were (i) equilibration time (0-45 d), (ii) 4 different types of Fe 0 , (iii) anion concentration (10 values), and (iv) use of MB and Orange II (O-II). The degree of dye discoloration, the pH, and the iron concentration were monitored in each system. Relative to the reference system, HCO 3 - enhanced the extent of MB discoloration, while Cl - , F - , HPO 4 -based systems for water remediation is a highly site-specific issue which has to include the anion chemistry of the water.2- , and SO 4 2- inhibited it. A different behavior was observed for O-II discoloration: in particular, HCO 3 - inhibited O-II discoloration. The increased MB discoloration in the HCO 3 - system was justified by considering the availability of FeCPs as contaminant scavengers, pH increase, and contact time. The addition of any other anion initially delays the availability of FeCPs. Conflicting results in the literature can be attributed to the use of inappropriate experimental conditions. The results indicate that the application of Fe 0 -based systems for water remediation is a highly site-specific issue which has to include the anion chemistry of the water., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Water contamination with toxic metals causes harmful effects on the environment and to human health. Although cucurbiturils have carboxyl groups in their portal that can interact with metal ions, there is a lack of studies about their use as metal adsorbent. This scenario has motivated conduction of the present study, which addresses the use of cucurbit[6]uril (CB[6]) and cucurbit[8]uril (CB[8]) for adsorbing Pb and Cr from water samples, in free forms and immobilized in poly(urethane) sponges. The adsorption kinetics revealed that CB[8] leads to faster adsorption compared to CB[6], with equilibrium achieved in 8 h for CB[8] and 48 h for CB[6] for both metals, and achieved up to 80% of decrease in metal concentration. The Langmuir isotherm model provided a better description of adsorption for Cr and Pb in CB[6] and Pb in CB[8] with a maximum concentration adsorbed of 32.47 mg g -1 for Pb in CB[6], while the Dubinin-Radushkevich model was more suitable for Cr adsorption in CB[8]. Sponges containing CB[6] and CB[8] have proven to be efficient for Pb and Cr remediation in tannery effluent samples, reducing Cr and Pb concentration by 42 and 33%, respectively. The results indicate that CB[6] and CB[8], whether used in their pure form or integrated into sponges, exhibit promising potential for efficiently adsorbing metals in aqueous contaminated environments., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Cyanobacterial algal hepatotoxins, called microcystins (MCs), are a global health concern, necessitating research on effective removal methods from contaminated water bodies. In this study, we synthesized non-fluorine MIL-100(Fe) using an environmentally friendly room-temperature method and utilized it as an adsorbent to effectively remove microcystin-LR (MC-LR), which is the most toxic MC congener. MIL-100(Fe) was thoroughly characterized, and its adsorption process was investigated under various conditions. Results revealed rapid MC-LR adsorption, achieving 93% removal in just 5 min, with the pseudo-second-order kinetic model indicating chemisorption as the primary mechanism. The Langmuir isotherm model demonstrated a monolayer sorption capacity of 232.6 µg g -1 at room temperature, showing favorable adsorption. Furthermore, the adsorption capacity increased from 183 µg g -1 at 20 °C to 311 µg g -1 at 40 °C, indicating an endothermic process. Thermodynamic parameters supported MC-LR adsorption's spontaneous and feasible nature onto MIL-100(Fe). This study highlights MIL-100(Fe) as a promising method for effectively removing harmful biological pollutants, such as MC-LR, from contaminated water bodies in an environmentally friendly manner., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The discharge of harmful dyes in water bodies is a serious pollution problem, dangerous for the ecosystem's equilibrium and human health. In this sense, the aim of this work was to determine the influence of electrolytes (NaCl, KCl, CaCl 2 and MgCl 2 ) in the adsorption of Reactive Blue BF-5G dye, the most common dye used in industrial process for fabric colouring, using bovine bone char as the adsorbent. The bovine bone char was characterized by pH of point of zero charge (pH PZC ), N 2 adsorption-desorption isotherms, Fourier transform-infrared spectroscopy (FT-IR) and X-ray diffractometry (XDR). The characterization revealed a mesoporous structure (pore mean diameter of 94 Å and S BET ∼107 m 2  g -1 ) with negative charge distribution at the surface (pH PZC  = 3.8). The adsorption experiments revealed that the presence of KCl enhanced the material adsorption capacity ( q max  = 195 mg g -1 ), that the Sips isotherm best fitted the experimental data ( R 2 > 0.9 except for KCl solution) and the adsorption process was mono- and multilayered. The kinetic adsorption experiments indicated that the inorganic electrolytes increased the initial adsorption velocity and the data was best modelled by the surface diffusional model (SDM), implying a resistance (aqueous > CaCl 2  > NaCl > MgCl 2  > KCl) to mass transfer at the surface of the pores which, in turn, prevented the dye diffusion to the interior of the adsorbent ( q e   = 71 mg g -1 ). Therefore, small quantities of KCl can be used to lower the mass transfer resistance and provide higher adsorption capacity with reduced time of operation, thus increasing the overall process efficiency.

The synthesis and characterization of graphitic carbon nitride (GCN) and its composites with calcined layered double hydroxide (CLDH) were examined in this investigation. The goal was to assess these composites' maximum adsorption capacity (q max ) for U(VI) ions in wastewater. Several different characterization methodologies were utilized to examine the fabricated substances. These methods encompass X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The GCN-CLDH composite displayed enhanced adsorption ability towards U(VI) ions due to its high surface functionality. Langmuir adsorption isotherm analysis showed that more than 99% of U(VI) ions were adsorbed, with a q max of 196.69 mg/g. The kinetics data exhibited a good fit for a pseudo-second-order (PSO) model. Adsorption mechanisms involving precipitation and surface complexation via Lewis's acid-base interactions were proposed. The application of the GCN-CLDH composite in groundwater demonstrated adsorption below the maximum permissible limit established by USEPA, indicating improved cycling stability. These observations underscore the capacity of the GCN-CLDH composite's proficiency in adsorbing U(VI) aqueous solutions containing radioactive metals., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

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.

The main goal of the present survey was to elaborate, characterize and evaluate the efficiency of ferrite-based nanoparticles modified with cetyltrimethylammonium bromide (CTAB) as potential magnetic nanoadsorbents to remove Remazol Brilliant Blue R (RBBR) from water. It is proposed an innovative nanomaterial architecture based on highly magnetic and chemically stable core@shell nanoparticles covered by an adsorptive surface layer of CTAB (CoFe 2 O 4 @γ-Fe 2 O 3 @CTAB). Samples of two different mean sizes (7.5 and 14.6 nm) were synthesized using a hydrothermal coprecipitation followed by surface treatment and functionalization. Batch tests were performed to evaluate the influence of contact time, temperature, pH, shaking rate, presence of interferents and mean size on the performance of the proposed nanomaterials. The kinetics of the adsorption process followed the pseudo-second-order model with an equilibrium time of 20 min. The adsorption capacity was estimated by the Langmuir isotherm model and was found to be 56.3 mg/g (smaller size) and 45.6 mg/g (larger size) at pH = 3 and a shaking rate of 400 rpm. The process was spontaneous, exothermic, and showed increased randomness. Sulphate ions negatively impacted the removal of RBBR. The best performance of the nanoadsorbent based on smaller mean sizes can be correlated to its larger surface area. Regeneration and readsorption tests showed that the nanoadsorbents retain more than 80% of their original removal capacity, therefore they can be effectively recycled and reused.

The competition impact and feedstock type on the removal of water pesticides using biochar have not yet been sufficiently investigated. Therefore, here we investigated the potentiality of three different biochars (BCs) derived from rice husk (RHB), date pit (DPB), and sugarcane bagasse (SBB) biowastes for the simultaneous removal of ten pesticides from water in a competitive adsorption system. The BCs structural characterization and morphology were investigated by XRD, FTIR spectroscopy and SEM analysis. The potential adsorption mechanisms have been investigated using various isothermal and kinetic models. RHB showed the highest removal percentages (61% for atrazine/dimethoate and 97.6% for diuron/chlorfenvinphos) followed by DPB (56% for atrazine/dimethoate and 95.4% for diuron/chlorpyrifos) and then SBB (60.8% for atrazine/dimethoate and 90.8% for chlorpyrifos/malathion). The higher adsorption capacity of RHB and DPB than SBB can be due to their high total pore volume and specific surface area (SSA). Langmuir model described well the sorption data (R 2  = 0.99). Adsorption equilibrium was achieved after 60 min for RHB, and 120 min for both DPB and SBB. The optimum adsorbent dose (g/L) was 10 for RHB and 4 for DPB and SBB. The removal efficiency of pesticides was enhanced by decreasing pH from 9 to 5 by RHB and to 3 by DPB and SBB. XRD and FTIR spectroscopy confirmed that BCs contain some active adsorption groups and metal oxides such as MgO, SiO, Al 2 O 3 , CaO, and TiO 2 that can play an effective role in the pesticides sorption. BET-N 2 adsorption analysis demonstrated that the BC pore size contributes significantly to pesticide adsorption. These findings indicate that RHB, DPB, and SBB have ability for adsorption of water pesticides even under acidic conditions. Therefore, the rice husk, date pit, and sugarcane bagasse biowastes could be pyrolyzed and reused as effective and low-cost sorbents for elimination of hazardous substances such as pesticides in the aqueous environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Heavy metals present in industrial effluents, when discharged into water channels, not only affect humans but also negatively impact plants and aquatic organisms. Sawdust is available readily in developing countries and can be used by small-scale industries for effluent water treatment containing low concentrations of bivalent zinc ions. This study explores the potential of sawdust-derived biosorbents, after boiling (SDB), chemical modification with formaldehyde (SDF), and sulfuric acid (SDS), for sequestration of Zn(II) from simulated wastewater as well as industrial effluents. The morphological analysis of the three biosorbents indicated a suitable porous structure with a pore size of 232.928 m 2 /g (SDB), 291.102 m 2 /g (SDF), and 498.873 m 2 /g (SDS). The functional analysis of native and metal-laden biosorbents indicated the role of - OH, - C = O, and - NH functional groups in Zn(II) binding. The process parameters were optimized and the spontaneous adsorption of Zn(II) was found to proceed by multilayer formation by following pseudo-second-order kinetics. SDS adsorbent (0.1 g) exhibited a greater potential for removal of Zn(II) from industrial effluents as compared to SDB and SDF at pH = 6.0 with the equilibrium adsorption capacity of 45.87 mg/g. Therefore, SDS could be a promising adsorbent for the treatment of wastewater in small-scale industries., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The effective removal of tetracycline antibiotics (TCs) from water is of great significance and remains a big challenge. In this work, a novel magnetized biochar (magnetic functionalized carbon microsphere, MF-CMS) was prepared by the coupling hydrothermal carbonization and pyrolysis activation of starch-rich rice waste using ZnCl 2 and FeCl 3 as activators. As the MF-CMS dose was 2.0 g/L, the initial concentration of TCs was 100 mg/L, the removal rates of tetracycline, doxycycline, oxytetracycline, and chlortetracycline were 96.02%, 96.10%, 96.52%, and 85.88%, respectively. The best modeled on pseudo second order, Langmuir adsorption model, and intraparticle diffusion kinetic models suggested that both chemisorption and physisorption occurred in all removal processes, in which chemisorption dominated. TCs were efficiently adsorbed through the combined effects of pore filling, electrostatic attraction, π-π interactions, and complexation reactions of surface functional groups (such as γ-Fe 2 O 3 and FeOOH). The removal rates of TCs after five cycles approximately decreased by 20%. And the cycling and metal ion release experiments of MF-CMS indicated that MF-CMS had good reusability, stability, and safety. The estimated cost of preparing MF-CMS is 5.91 USD per kg, and 1 kg of MF-CMS (consuming 8 kg of waste rice) can approximately treat 0.55 tons of TCs wastewater. Overall, the magnetic biochar derived from starch-rich rice waste as an adsorbent has promising and effective for the removal of TCs from water, but also provides a new idea for the resourceful treatment of solid waste., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

In this work, we develop a mussel-inspired biosorbent combined with graphene oxide for removal of organic dyes in water sources. The composite was prepared via self-polymerization of dopamine in weak alkaline solution containing graphene oxide at ambient condition. Morphological and structural studies revealed that polydopamine has gradually grown to cover the surface of graphene oxide flakes, partially reduced these flakes, and somehow form many grains (size around 20 nm) on the flakes instead of making very large aggregates as usual. The mass ratio between two components of the composite was also investigated to find the optimal one which provides enough surface area (20 m 2 .g -1 ) and maintain adhesive sites in order to ensure high-efficiency removal of organic molecules. The adsorption kinetics and isotherms of as-prepared adsorbent towards methylene blue were found to fit well with pseudo-first order kinetics model and Langmuir isotherm. The maximum adsorption capacity (q m ) and Langmuir constant (k L ) were estimated to be 270 mg.g -1 and 0.49 L. mg -1 . The as-prepared bio-sorbent is very promising for remediation of water sources contaminated with cationic organic molecules and heavy metal ions., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Vu Thi Thu reports financial support was provided by National Foundation for Science and Technology Development., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Nanocellulose/polyethylenimine composites have attracted growing attention due to their versatility as new materials for application in different fields. Water remediation is one of the traditional applications of these composites and their investigation as adsorbents for single water pollutants is well established. However, most water resources such as rivers, lakes, and even oceans contain complex mixtures of pollutants. Despite several recently published reviews on water purification technology, they only focused on these material as single pollutant removers and hardly mentioned their capacity to simultaneously recover multiple pollutants. Therefore, there is still a gap in the archived literature considering nanocellulose/polyethylenimine composites targeting water remediation with multiple water pollutants. In this review, methods for synthesizing such composites are classified and compared according to the mechanism of reactions, such as chemical crosslinking and physical adsorption, while outlining advantages and limitations. Then, the water pollutants mainly targeted by those composites are discussed in detail to expound the relationship between the synthesis method and the type and adsorption capacity. Finally, the last section presents challenges and opportunities of these nanocellulose/polyethylenimine composites as emerging sorbents for sustainable multiple water pollutants purification technologies. This review aims to lay out the basis for future developments of these composites for multiple water pollutants., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023. Published by Elsevier B.V.)

Arsenic (As(V))-contaminated water is a major global threat to human health and the ecosystem because of its enormous toxicity, carcinogenicity, and high distribution in water streams. Thus, As(V) removal in the environmental samples has received considerable attention. Till now, numerous metal-organic framework materials have been used for the As(V) removal from the aqueous medium, but low As(V) removal and instability of the adsorbents have severely cut off their practical applications. In this study, a ferrocene-encapsulated zeolitic imidazolate framework-67 (Fc-ZIF-67) material was synthesized for As(V) removal from an aqueous solution at neutral pH using a simple solution mixing process. The ferrocene encapsulation provides water-stable and structural defects to ZIF-67. Furthermore, the ferrocene molecule and imidazole linker can enhance As(V) adsorption via both chemisorption and physisorption. The novel Fc-ZIF-67 adsorbent exhibited superior As(V) adsorption performance with an adsorption capacity of 63.29 mg/g at neutral pH. The Langmuir and Freundlich isotherm models were also used to analyze adsorption behavior., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Converting biomass into biochar (BC) as a functional biocatalyst to accelerate persulfate activation for water remediation has attracted much attention. However, due to the complex structure of BC and the difficulty in identifying the intrinsic active sites, it is essential to understand the link between various properties of BC and the corresponding mechanisms promoting nonradicals. Machine learning (ML) recently demonstrated significant potential for material design and property enhancement to help tackle this problem. Herein, ML techniques were applied to guide the rational design of BC for the targeted acceleration of nonradical pathways. The results showed a high specific surface area, and O% values can significantly enhance nonradical contribution. Furthermore, the two features can be regulated by simultaneously tuning the temperatures and biomass precursors for efficient directed nonradical degradation. Finally, two nonradical-enhanced BCs with different active sites were prepared based on the ML results. This work serves as a proof of concept for applying ML in the synthesis of tailored BC for persulfate activation, thereby revealing the remarkable capability of ML for accelerating bio-based catalyst development.

The conversion of agricultural waste into high-value carbon products has been an attractive area in waste management strategy. This study highlighted the synthesis and effectiveness of green pea peels (GPP), green pea biochar (GPBC), and nano-ferromagnetic green pea biochar (NFGPBC) by the ferrous/ferric co-precipitation synthesis method for eliminating cationic dyes molecules from solutions. The morphological, physicochemical, and structural properties of GPP, GPBC, and NFGPBC were approved by Scanning Electron Microscopy (SEM), Transmission Emission Microscopy (TEM), Energy Dispersive X-ray (EDX), Bruneau Emmett Teller (BET), Fourier Transform Infrared spectroscopy (FTIR), and X-ray Diffraction (XRD) techniques. Vibrating Sample Magnetometry (VSM) analysis confirmed the NFGPBC magnetization performance. The capacity of each adsorbent for methylene blue removal was evaluated at various parameters of material dosage (50-250 mg/150 mL), pH (2-12), initial concentration (50-250 mg/L), contact time (0-90 min) and temperature (20-60 °C). The three developed adsorbent materials GPP, GPBC, and NFGPBC, possessed reasonable BET surface areas of 0.6836, 372.54, and 147.88 m 2 g -1, and the corresponding monolayer adsorption capacities of 163.93, 217.40, and 175.44 mg/g, respectively. The superior performances of GPBC and NFGPBC were due to their increased surface area compared with the parent green pea peels (GPP). The results from adsorption kinetics studies of all prepared materials were pseudo-second-order and Elovich kinetics models. The thermodynamic parameters exhibited MB sorption's favorability, spontaneity, and endothermic nature. The NFGPBC material experienced Vander Waal forces, electrostatic interaction, hydrogen bonding, and hydrophobic interactions as predominant modes of the solid-liquid interaction. The regeneration, recycling, and reusability of the synthesized GPP, GPBC, and NFGPBC performed at five adsorption cycles revealed that NFGPBC demonstrated excellent cyclical performances attaining a minimum 8.9% loss in capacity due to paramagnetic properties. Thus, NFGPBC is a green, efficient, and eco-friendly material recommended for large-scale production and application in wastewater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The increasing threats of oxo-anions in drinking water have posed a serious threat to human health, aquatic environment, ecology, and sustainability. Accordingly, developments of cost-effective and sustainable nanomaterials for water remediation are on top priority and highly sought in global research community. Carbon nano-onions (CNOs) are one of the emerging nanomaterials for water purification because of its unique morphology, surface reactivity, high density of surface-active sites, and microporous structure. Herein, flaxseed oil-derived CNOs are utilized as efficient adsorbent for the removal of toxic oxo-anions. Aside from the green and economic nature, CNOs provide high adsorption efficiency ~ 806.45 mg g -1 for the removal of [Formula: see text] (99.9%) from aqueous system at ambient temperature, neutral pH in 70 min. The adsorption of [Formula: see text] onto CNOs was well fitted in pseudo-second order kinetics and followed the Langmuir adsorption isotherm model. The adsorption process was determined to be exothermic and spontaneous from the resulting thermodynamic characteristics. Furthermore, the high hydrophobic nature of CNOs make it recycling simpler. The real-life applicability of CNOs towards [Formula: see text] removal was tested in tap water, river water, and dam water. With all these observed results, CNOs show promise for practical water remediation applications., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Sargassum algae has become a major environmental issue due to its abundance in the Pacific Ocean with hundreds of tons reaching the beaches of the Mexican Caribbean every year. This generates large quantities of decomposing organic matter that have a negative impact on the region's economy and ecosystems. Sargassum valorization has turned out to be a fundamental aspect to mitigate its environmental impact. This study proposes the use and application of untreated Sargassum biomass for the decontamination of waters polluted with lead (Pb) and cadmium (Cd) through single and binary adsorption tests. Physicochemical and textural properties examined by SEM, XRD, and FT-IR elucidated that Sargassum biomass is viable to be used as a potential environmental benign adsorbent, exhibiting Cd(II) and Pb(II) adsorption capacities as high as 240 mg g -1 and 350 mg g -1 , respectively, outperforming conventionally used adsorbents. This is attributed to its morphology, favorable surface charge distribution, and the presence of -OH and -COH groups. A strong affinity between the biomass and metal pollutants was evidenced by a thermodynamics study, showing a spontaneous and endothermic process. This work sets a practical route for the utilization of the Sargassum biomass, demonstrating its applicability as a potential material for heavy-metal-polluted water remediation, making a substantial contribution to a circular economy system.

This work shows the efficiency of wash waters from lipopeptide production as a remediation strategy to treat urban water samples contaminated with p-cresol. The harvesting step in surfactin production involved a centrifugation step, generating a major soluble fraction and a fraction that is adsorbed to the biomass. The adsorbed fraction was recovered by washing steps. These wash waters containing lipopeptides (mostly surfactins), were successfully used to adsorb and solubilize p-cresol. The method of decontamination applied to an artificially contaminated natural water was monitored using a biosensor based on laccase/magnetic nanoparticles. Given the amount of surfactin within the wash water, the removal of p-cresol from artificially contaminated water was approximately 46.0%. This result confirms the successful and sustainable application of surfactin-rich wash waters to remove p-cresol from artificially contaminated natural water. The adsorption mechanism is potentially based on a multi-layer adsorption process, considering Langmuir and Freundlich adsorption isotherms.

Herein, ethylene glycol (EG)-modified Zn/Cu hydroxy double salts (HDS) were synthesized using a facile synthetic approach. The formation of layered structure and presence of EG in the interlayer region were confirmed using PXRD and FTIR techniques. Furthermore, XPS analysis was used to confirm presence of metal ions in synthesized HDS. The surface area and pore size diameter of the HDS was found to be 32.30 m 2 g -1 and 2.22 nm, respectively, using BET. The role of HDS was evaluated for its potential application as a sorbent for Congo red (CR) dye uptake. Batch studies were conducted to examine the impact of key variables, i.e., pH, time, adsorbent dosage and dye concentration on adsorption efficiency of HDS. Linear-nonlinear isotherm and kinetic models were employed for detailed analysis of experimental data. Langmuir, Freundlich and Temkin isotherm models were subsequently utilized to fit equilibrium data, among which Langmuir demonstrated to be most accurate. The maximum monolayer adsorption capacity estimated using Langmuir model was computed to be 181.81 mg g -1 . The kinetic data follows pseudo-second-order model having good R 2 value (0.999). Additionally, thermodynamic study suggested spontaneous and endothermic nature of adsorption process having reusability up to 5 cycles with removal efficiency more than 85%.

The use of composites of stimuli-responsive polymers with polysaccharides during water remediation has gained impetus in recent years. The applications of composites of polysaccharides (chitosan, cellulose and cyclodextrin) with stimuli-responsive polymers (CO 2 -, thermo-, light-, and pH-responsive polymers) were reviewed in this paper. These smart composites have tuneable physicochemical properties that enable them to form tailor-made adsorbents for the adsorption of pollutants from water. Adsorption and desorption of pollutants can be switched on and off by adjusting appropriate stimuli without the use of toxic organic solvents. The polysaccharide/stimuli-responsive polymer-based adsorbents, therefore, can be easily recovered during water remediation by adjusting the stimuli, and this makes them to be eco-friendly and recyclable. These attributes of the polysaccharide/stimuli-responsive polymer-based composites were explored in detail in this review. In addition, the challenges associated with the use of these smart composites as well as their future prospects were also articulated in this paper., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

New classes of biosorbents are needed for various environment remediation applications. Thus, a facile and benign approach to synthesize porous biosorbents was developed using acidic or alkaline one-step ball milling of hickory wood biomass (AcBH and AlBH, respectively) without any external heat treatment, and their properties were compared. AcBH and AlBH were richer in O-containing functional groups, had enhanced porous structure and greater ability to remove crystal violet (CV, 476.4 mg g -1 ) and Congo red (CR, 221.8 mg g -1 ) dyes from aqueous solution, respectively, relative to hickory wood ball milled at neutral pH. Freundlich isotherm and pseudo second order kinetic models best fitted CR and CV adsorption onto biosorbents, indicating a mainly surface complexation adsorption mechanism. Further, both sorbents exhibited excellent stability and dye adsorption reusability. These results demonstrate that acidic and alkaline one-step ball milling is a facile and efficient approach for converting wood biomass into environmentally friendly biosorbents., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Natural or industrial hexavalent chromium water pollution continues to be a worldwide unresolved threat. Today, there is intense research on new active and cost-effective sorbents for Cr(VI), but most still exhibit a critical limitation: their powdered nature makes their recovery from water cost and energy consuming. In this work, Al(OH) 3 , MIL-88-B(Fe), and UiO-66-NH 2 Cr(VI) sorbents were immobilized into a poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) polymeric substrate to develop an easily reactivable and reusable water filtering technology. The immobilization of the sorbents into the PVDF-HFP porous matrix modified the macro and meso-porous structure of the polymeric matrix, tuning in parallel its wettability. Although a partial blocking of the Cr(VI) adsorptive capacity was observed for of Al(OH) 3 and MIL-88-B(Fe) when immobilized into composite membranes, PVDF-HFP/UiO-66-NH 2 filter (i) exceeded the full capacity of the non-immobilized sorbent to trap Cr(VI), (ii) could be reactivated and reusable, and (iii) it was fully functional when applied in real water effluents., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The integration of polymers with biomaterials offers promising and effective nanomaterials with intrinsic and extrinsic properties that are utilized in several applications. The present work reported the development of Polyacrylonitrile (PAN) supported biosorbent (Moringa oleifera, (MO)) which was utilized for the removal of Congo red (CR) dye from aqueous solution. MO loaded polyacrylonitrile (PAN/MO) nanofibrous biosorbent was prepared by solvent homogenization method followed by electrospinning for the deposition of nanofibers. The developed nanofibrous biosorbent was investigated by several analytical techniques such as FESEM, TEM, XRD, FTIR, and XPS to study the material properties along with their control counterparts. The adsorption experiments such as the effect of contact time, effect of concentration, effect of pH, and reusability studies were performed. The adsorption capacity of the nanofibrous biosorbent is ∼52 mg g -1 , which is significant as bulk sorbent when compared with other activated carbon in powder form. The adsorption capacities vary with an increase in the dye concentration and obtained ∼88% of dye removal. The adsorption data are validated using the empirical pseudo-first-order, pseudo-second-order kinetic models, and the mechanism involved in the adsorption phenomena was investigated by Langmuir and Freundlich isotherm models, respectively. The biosorbent follows the pseudo-second-order kinetics and Freundlich isotherm, which involves in multilayer adsorption phenomena. In a nutshell, the present work corroborated the importance of bio-based natural sorbent available in nature which can be effectively engineered with polymeric materials for obtaining novel hybrid materials to explore their inherent properties for various applications., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The ever increasing concentration of toxic and carcinogenic hexavalent chromium (Cr (VI)) in various environmental mediums including water-bodies due to anthropogenic activities with rapid civilization and industrialization have become the major issue throughout the globe during last few decades. Therefore, developing new strategies for the treatment of Cr(VI) contaminated wastewaters are in great demand and have become a topical issue in academia and industry. To date, various techniques have been used for the remediation of Cr(VI) contaminated wastewaters including solvent extraction, adsorption, catalytic reduction, membrane filtration, biological treatment, coagulation, ion exchange and photo-catalytic reduction. Among these methods, the transformation of highly toxic Cr(VI) to benign Cr(III) catalyzed by metallic nanoparticles (M-NPs) with reductant has gained increasing attention in the past few years, and is considered to be an effective approach due to the superior catalytic performance of M-NPs. Thus, it is a timely topic to review this emerging technique for Cr(VI) reduction. Herein, recent development in synthesis of M-NPs based non-supported, supported, mono-, bi- and ternary M-NPs catalysts, their characterization and performance for the reduction of Cr(VI) to Cr(III) are reviewed. The role of supporting host to stabilize the M-NPs and leading to enhance the reduction of Cr(VI) are discussed. The Cr(VI) reduction mechanism, kinetics, and factors affecting the kinetics are overviewed to collect the wealthy kinetics data. Finally, the challenges and perspective in Cr(VI) reduction catalyzed by M-NPs are proposed. We believe that this review will assist the researchers who are working to develop novel M-NPs catalysts for the reduction of Cr(VI)., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Developing green inexpensive and effective adsorbents is critically needed for elimination of antibiotics from contaminated water. The current study assessed the nanostructured activated biochar (nPPAB) derived from pomegranate peels (PP) as a promising sorbent for efficient removal of the antibiotic ciprofloxacin (CIP). The results affirm that the second order and Langmuir models fit well to adsorption kinetics and equilibrium data respectively. The nPPAB adsorption capacity of Langmuir (q max ) for CIP was 142.86 mg g -1 which is 26.85 times greater than that of bulk PP. Hydrogen bonding, π-π interaction, hydrophobic and electrostatic interactions are the dominant mechanisms of CIP adsorption by nPPAB. The efficiency of nPPAB for CIP removal from real wastewater using batch and packed-bed reactor were 89.94 and 84.74% respectively. This study clearly demonstrated the substantial capacity of nPPAB as an ecofriendly, feasible, and in-expensive adsorbent for successful elimination of CIP from wastewater., (Copyright © 2022 Elsevier Inc. All rights reserved.)

In the present study, the optimization of factors for the fabrication of highly adsorptive activated carbon from agricultural waste (date stone) was investigated by using ZnCl 2 as a chemical agent during the heat treatment. ZnCl 2 acts as a dehydration agent during the heat treatment, allowing a better porosity. In addition, it boosts the fragmentation of the lignocellulosic structure and the condensation of carbon rings. The findings of this investigation showed that the synthesis conditions for better ZnCl 2 chemical/heat carbonization to fabricate an adsorbent from date stone are 700 °C, 120 min, and 2.0 g/g. The characterization analysis showed that the as-prepared activated carbon exhibits a surface area of 1036 m 2 /g, an iodine number of 928.5 mg/g, and phenol number of 2.1 mmol/g, which are comparable to commercial activated carbons. Batch sorption tests to remove methylene blue (MB) from water showed a maximum adsorption capacity of 384.6 mg/g using the prepared activated carbon. Equilibrium data was best fitted by the Langmuir isotherm model. It was found also that the kinetic adsorption data obeyed the pseudo-first order, and both external diffusion and intra-particle diffusion control the adsorption. Based on the obtained results, the optimization of synthesis conditions may help the transfer of technology in terms of agriculture-based material valorization towards the environmental remediation., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Low-cost and largely available industrial by-products such as calcite (CaCO 3 ) have been considered as sorbents to remediate wastewaters from toxic elements, such as lead, in compliance with the European circular economy strategy. To date few articles are reporting results on lead sorption at the calcite-water solution interface by X-ray photoelectron spectroscopy (XPS) and this investigation aims to clarifying the mechanism of the interaction of Pb 2+ model solutions over a wide concentration range, from 0.1 μM to 80 mM, with commercial calcite. X-ray powder diffraction (XRPD), scanning electron microscopy (SEM, EDX) and XPS analysis indicate that when CaCO 3 particles are soaked in Pb 2+ 0.1 mM and 1 mM solutions, hexagonal platelets of hydrocerussite [(PbCO 3 ) 2  Pb(OH) 2 ] precipitate on its surface. When the concentration of Pb 2+ is equal or higher than 40 mM, prismatic acicula of cerussite [PbCO 3 ] precipitate. Solution analysis by atomic emission spectroscopy (ICP-AES) and ICP-mass spectrometry (ICP-MS) indicate that Pb 2+ removal efficiency is nearly 100%; when the initial Pb 2+ concentration was equal to 0.1 μM it was below the limit of detection (LOD) and the efficiency could not be determined. The sorption capacity (q e ) increases linearly with increasing initial Pb 2+ concentration up to a value of 1680 (20) mg/g when the initial Pb 2+ concentration is 80 mM. These findings suggest that heterogeneous nucleation and surface co-precipitation occur and calcite can be well considered a very promising sorbent for Pb 2+ removal from wastewaters within a wide initial concentration range., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Herein, feedstock (pinewood, rice straw, and dairy manure) and pyrolysis temperature (300, 500, and 700 °C) were selected as the influencing factors of properties of biochar (BC) to identify the contribution of biochar's matrix on Cr(VI) removal by BC-supported sulfidated zero-valent iron (S-ZVI/BC). Results showed that higher temperature was more conducible to improve the electrochemical properties and specific surface areas of composites. Raman spectra of S-ZVI supported by pinewood-derived BC (S-ZVI/PBC) showed the I D /I G ratio increased from 0.639 to 0.975 for the composites prepared at 300-700 °C, indicating the increased structural defects and resulting in the greatest Cr(VI) removal (35.81 mg g -1 ) and reduction (30.21 mg g -1 ) amounts of S-ZVI/PBC700. Besides, S-ZVI/PBC exhibited greater electrochemical reactivity and surface area than S-ZVI harbored by BC from dairy manure and rice straw. Additionally, Pearson correlation analysis revealed that Cr(VI) removal was significantly positively correlated to surface area (R 2  = 0.90) and negatively correlated to Tafel corrosive potential (R 2  = 0.88). Both desorption experiment and XPS spectra of spent sorbents showed that reduction predominated the detoxifying mechanism of Cr(VI) followed by adsorption (due to corrosively-generated iron oxides and BC) and precipitation (Cr 2 S 3 ). This suggested that biochar with greater specific surface area and electrical conductivity is more favorable to immobilize S-ZVI with respect to Cr(VI) removal., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Pharmaceutical compounds are designed to elicit a biological reaction in specific organisms. However, they may also elicit a biological response in non-specific organisms when exposed to ambient quantities. Therefore, the potential human health hazards and environmental effects associated with pharmaceutically active compounds presented in aquatic environments are being studied by researchers all over the world. Owing to their broad-spectrum occurrence in various environmental matrices, direct or indirect environmental hazardous impacts, and human-health related consequences, several pharmaceutically active compounds have been categorized as emerging contaminants (ECs) of top concern. ECs are often recalcitrant and resistant to abate from water matrices. In this review, we have examined the classification, occurrence, and environmental hazards of pharmaceutically active compounds. Moreover, because of their toxicity and the inefficiency of wastewater treatment plants to remove pharmaceutical pollutants, novel wastewater remediation technologies are urgently required. Thus, we have also analyzed the recent advances in microbes-assisted bioremediation as a suitable, cost-effective, and eco-friendly alternative for the decontamination of pharmaceutical pollutants. Finally, the most important factors to reach optimal bioremediation are discussed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Biochar-harbored zero-valent iron (ZVI/BC) has been extensively used to detoxify hexavalent chromium (Cr(VI)). However, the role played by biochar in promoting electron transfer of ZVI and Cr(VI) reduction was not fully uncovered. Herein, three biomass modeling components (cellulose, hemicellulose, and lignin) and their blends were utilized to synthesize ZVI/BC via co-pyrolysis with hematite. X-ray diffraction analysis showed that hematite was successfully reduced to ZVI in nitrogen ambience. Batch sorption experiment showed that mass ratio (hematite to lignocellulosic component) of 1:20 is most optimal for reduction of Cr(VI) by ZVI/BCs. ZVI supported by BC derived from cellulose, hemicellulose, and their binary mixture demonstrated better Cr(VI) removal capacity (23.8-38.3 mg g -1 ) owing to higher ordered and graphitic carbon structure as revealed by Raman spectrum. In addition, lower Tafel corrosion potentials and smaller electrochemical impedance arc radiuses were observed based on electrochemical analysis, suggesting their higher electrical conductivity and faster electron transfer, whereas the BCs derived from lignin and lignin-containing hybrids were not conducive to electron transfer of ZVI due to lower degree of graphitization, thus compromising Cr(VI) removal by ZVI/BC (7.7-17.7 mg g -1 ). As per X-ray photoelectron spectroscopy analysis, reduction, complexation, and co-precipitation were the main mechanisms for Cr(VI) removal. The present study provided a scientific evidence for screening plant-derived biomass feedstock with high contents of cellulose and hemicellulose and low lignin content to fabricate ZVI/BC to achieve high Cr(VI) removal., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Porous carbon serves as a green material for efficient wastewater purification by adsorption and advanced oxidation processes. However, a clear understanding of the simultaneous removal of multiple pollutants in water is still ambiguous. Herein, the synergistic effect of adsorption and peroxydisulfate (PS) activation on kinetics and mechanism of removing single and binary antibiotic pollutants, sulfamethoxazole (SMX) and ibuprofen (IBP), from water by biomass-derived N-doped porous carbon was investigated. Our findings suggest that adsorption contributed to efficient removals of SMX/IBP. Comparative quenching experiments and electrochemical analysis demonstrated that hydroxyl (•OH) and sulfate (SO 4 •- ) radicals, as well as singlet oxygen ( 1 O 2 ) led to the catalytic degradation of SMX, while only 1 O 2 reacted for IBP oxidation. Superoxide ion (O 2 •- ) radicals were not related to SMX/IBP degradation. Electron transfer pathway accounted for PS activation but was not involved in direct SMX/IBP oxidation. Only slight differences were found between the degradation kinetics of SMX and IBP in the binary and single SMX or IBP solutions. This arose from the non-selective effect of adsorption and 1 O 2 attack for SMX/IBP removal, and the weak selective oxidation process of SMX by •OH and SO 4 •- . This study provides a new viewpoint on the role of adsorption in catalysis and enriches the mechanistic study of multi-component antibiotic degradation., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The development of manganese (Mn) oxides (MnOx) modified biochar (MnOBC) for the removal of pollutants from water has received significant attention. However, a comprehensive review focusing on the use of MnOBC for the removal of organic and inorganic pollutants from water is missing. Therefore, the preparation and characterization of MnOBC, and its capacity for the removal of inorganic (e.g., toxic elements) and organic (e.g., antibiotics and dyes) from water have been discussed in relation to feedstock properties, pyrolysis temperature, modification ratio, and environmental conditions here. The removal mechanisms of pollutants by MnOBC and the fate of the sorbed pollutants onto MnOBC have been reviewed. The impregnation of biochar with MnOx improved its surface morphology, functional group modification, and elemental composition, and thus increased its sorption capacity. This review establishes a comprehensive understanding of synthesizing and using MnOBC as an effective biosorbent for remediation of contaminated aqueous environments., (Copyright © 2021. Published by Elsevier Ltd.)