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Soil contamination by heavy metals represents a critical environmental risk. Innovative and sustainable remediation strategies are urgently needed to address this global challenge. Biochar, derived from biomass pyrolysis, has gained attention as an eco-friendly material for heavy metal adsorption. However, its adsorption performance is highly dependent on the pyrolysis conditions and can be further enhanced through functionalization. In this study, wheat straw biochar was optimized for enhanced porosity, carbon content, and structural stability and further functionalized by incorporating metal-organic frameworks (MOFs) to create a high-performance nanocomposite. Three MOFs-ZIF-8, UiO-66, and MIL-100(Fe)-were evaluated for their Cu 2⁺ and Pb 2⁺ adsorption capacities. MIL-100(Fe) emerged as the most effective due to its high pore volume and iron-active sites. Coating biochar with MIL-100(Fe) increased its surface area sixfold, achieving 419 m 2 ∙g -1 , and doubled its sorption capacity for heavy metals in soil (142 mmol·kg -1 for Cu 2⁺ and 156 mmol·kg -1 for Pb 2⁺ ). Advanced characterization techniques, including XAFS, XRD, and SEM-EDX, revealed that the sorption mechanisms were dominated by complexation and cation exchange, with the nanocomposite demonstrating superior metal immobilization compared to neat biochar. These findings highlight the potential of the nanocomposite as an effective amendment for reducing heavy metal toxicity in soils., Competing Interests: Declarations. Ethical approval: No ethical approval was necessary for this study. Consent to participate: All participants in this study consent to participation. Consent for publication: All authors consent to this publication. Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Laccase from Trametes hirsuta was immobilized on amino-functionalized silica by adsorption and covalent binding using glutaraldehyde (GLA) and glyoxal (GLX) as cross-linkers. The immobilization process was optimized applying the Box-Behnken methodology. The immobilized biocatalysts were characterized using scanning electron microscopy, Brunauer-Emmett-Teller surface area and Barrett-Joyner-Halenda pore size analyses, and elemental analysis. Covalent immobilization proved to be better than adsorption based on the specific activity, immobilization yield, and stability in hospital wastewater (HWW) of the biocatalysts. The biocatalyst prepared using GLA under optimized conditions (laccase loading: 10 kU/L, pH 5, temperature: 5 °C, immobilization time: 8 h, and GLA amount: 100 mM) demonstrated better stability to pH, temperature, and other denaturants, compared to free laccase. It exhibited good catalytic potential to remove phenolic compound acetaminophen (83%) and other trace organic contaminants (TrOCs) such as mefenamic acid (86%), indomethacin (73%), carbamazepine (62%), ibuprofen (43%), naproxen (37%), and ketoprofen (27%), in a mixture from a real non-treated hospital effluent spiked with 1 µg/L of each of the above compounds. In addition, the measured catalytic parameters (K m , k cat and k cat /K m ) of acetaminophen (free laccase vs. immobilized laccase (AFHMS-GLA-Lac)) are relatively similar. This is one of the first evaluative studies on different immobilization strategies using the Box-Behnken optimization method to develop efficient and stable laccase biocatalysts by immobilization on amino-functionalized silica for real hospital wastewater treatment., Competing Interests: Declarations. Ethical approval and consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The present work investigates, for the first time, the synthesis of a composite film based on glutaraldehyde-cross-linked chitosan (GA-CS) and a natural zeolite (H-ZSM-5) and its application for the removal of hexavalent chromium (Cr(VI)) from aqueous solutions under wide experimental conditions. The composite film (GA-CS-ZEO) characterization by using various analytical techniques confirms its successful production with promising physical, chemical, and thermal properties. The use of the response surface methodology (RSM) for the optimization of the Cr(VI) adsorption by this composite shows that that the maximum removal efficiency (82.39%) was achieved for a Cr(VI) concentration of 50 mg L -1 , an initial pH of 2.0, a contact time of 100 min, and a temperature of 20 °C. Moreover, the analysis of variance (ANOVA) and 3D graphs indicated that the pH and initial Cr(VI) concentration were the main factors that influence the Cr(VI) uptake efficiency. Besides that, the Cr(VI) removal by the GA-CS-ZEO was found to be spontaneous and endothermic and occurs mainly via physical mechanisms involving electrostatic interactions and hydrogen bonding. Regeneration study of the Cr(VI)-loaded composite showed that Cr(VI) can be rapidly and efficiently desorbed by 0.1 M sulfuric acid. The results of the current research work highlight the important adsorption potential of Cr(VI) by the GA-CS-ZEO composite film and underscore its attractiveness and suitability for water treatment applications., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In order to improve the adsorption and immobilization capacity of biochar for Cd and atrazine in soil, the biochar was prepared from corn straw and modified by dry ball milling under various conditions. Compared with the pristine biochar (PB), the ball-milled biochar (BB) had a larger specific surface area and more pores, the number of oxygen-containing functional groups increased significantly, and the adsorption capacity of Cd and atrazine increased by 9.0% and 139.4%, respectively. Compared with a single pollutant, the adsorption capacity of PB and BB for Cd increased by 4.6% and 9.3%, respectively, and the adsorption capacity of atrazine increased by 97.1% and 11.5%, respectively. The increase of atrazine adsorption after modification was higher than that of Cd. In the desorption test, ball-milled modification decreased the desorption rate of Cd and atrazine, while the desorption rate of atrazine was much lower than that of Cd. Therefore, the biochar modified by ball-milled had stronger adsorption and fixation capacity for Cd and atrazine, which provides a basis for more effective remediation of soil polluted by Cd and atrazine., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Highly effective MIL-100(Fe) adsorbent material was successfully synthesized from (NH 4 ) 2 Fe(SO 4 ) 2 ·6H 2 O and H 3 BTC precursors under mild conditions. Characteristics regarding crystal structure, functional groups, elemental composition, surface morphology, specific surface area, and surface charges revealed the formation of pure and microporous MIL-100(Fe) adsorbent with a super surface area (1916.26 m 2 /g). The results showed that the adsorption of tartrazine organic dye was affected by adsorption time, solution pH, adsorbent dosage, pollutant concentration, and temperature. The adsorption kinetics was best described by a pseudo-second-order model with a coefficient of determination R 2  = 0.999. The Toth and Langmuir models best fitted to the experimental data, showing a maximum adsorption uptake of 104.913 mg/g, which is much better than many other adsorbents. The thermodynamic parameters revealed the adsorption process of tartrazine on MIL-100(Fe) material was exothermic, spontaneous, and mainly controlled by chemical adsorption. The desorption and reuse ability of the material was effectively performed by using ethanol (98%), which showed an adsorption efficiency still remained at 88% after five adsorption cycles. This work provides an environmentally friendly synthesis of MIL-100(Fe) material with high adsorption efficiency and opens up opportunities to develop new materials for organic dye treatment in water., Competing Interests: Declarations. Ethics approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In the current work, three adsorbent materials were developed: biochar derived from date palm fiber (C), date palm fiber biochar/chitosan nanoparticles (CCS), and biochar/chitosan nanoparticle composite supplemented with glutamine (CCSG). These compounds were used as solid adsorbents to remove As 5+ from polluted water. Several characterization approaches were used to investigate all the synthesized solid adsorbents, including thermogravimetric analysis, N 2 adsorption/desorption isotherm, scanning electron microscopy, transmission electron microscopy (TEM), attenuated total reflectance with Fourier transform infrared, and zeta potential. Date palm fiber biochar/chitosan/glutamine nanocomposite (CCSG) demonstrated good thermal stability, with a maximum specific surface area of 518.69 m 2 /g, a mesoporous size of 2.06 nm, total pore volume of 0.25 cm 3 /g, TEM average particle size of 38 nm, and pH PZC of 6.9. Contact time (5-60 min), pH (1-9), starting As 5+ concentration (50-500 mg/L), adsorbent dose (0.1-2.0 g/L), temperature (27-45 °C), and ionic strength (0.05-0.40 mol/L) were among the sorption parameters that were investigated in order to improve the adsorption conditions. It is observed that the modified samples were effectively able to remove As 5+ (CCS; 256.0 and CCSG; 376.0 mg/g) than unmodified ones (C; 150.5 mg/g). The As 5+ removal procedure corresponded well with Langmuir isotherm model. Thermodynamic and kinetic experiments show that the Elovich, pseudo-first order, and Van't Hoff plot with endothermic, spontaneous, and physisorption nature are the best fitted models. EDTA has the highest desorption efficiency percentage (98.8%). CCSG demonstrated enhanced reusability after six application cycles of As 5+ adsorption/desorption, with only a 4% decrease in the efficiency of adsorption. This work shows that adding glutamine to the DPF biochar/chitosan composite reinforces it, resulting in the fabrication of a solid adsorbent that shows promise for use in water remediation., Competing Interests: Declarations. Ethics approval: Not applied. This study did not involve human participants and/or animals. Consent to participate: Not applied. Consent for publication: Not applied. Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The problem faced during bio-based activated carbon synthesis is related to its low yield production, which is plausibly due to intricate conventional activation processes, along with utilization of corrosive chemical activator. Therefore, in this study, the activated carbon synthesis from palm kernel shell as starting material has been carried out via a facile solid-solid mixing (mechanochemical) activation. The feasibility and optimization of the high-yielded palm kernel shell activated carbon production has been done via the L 9 Taguchi orthogonal array, whereby the larger-the-better signal to noise (S/N) ratio has been applied to determine the optimum operating conditions. Four parameters have been studied including the activation temperature (600-800 °C), impregnation ratio (1-3:1), activation time (60-120 min), and nitrogen flow rate (300-900 mL/min). Depending on the operating conditions, the activated carbon yield is ranging from 10 to 50 wt.%. Upon optimization, both the pristine precursor and activated carbon at the optimal conditions are characterized in terms of their surface morphology, porosity, and the surface functionalities. In context of carbon dioxide adsorption, the adsorption capacity at an ambient condition is found to be approximately 1.65 mmol/g, which is comparable to the values reported in the literatures., Competing Interests: Declarations. Competing Interest: The authors have no relevant financial or non-financial interests to disclose., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This study shows the efficiency of WH-C450, an adsorbent obtained from water hyacinth (WH) biomass, in the removal of sulfamethoxazole (SMX) from aqueous solutions. The process involves calcination of WH at 450 °C to produce an optimal adsorbent material capable of removing up to 73% of SMX and maximum SMX adsorption capacity of 132.23 mg/g. Fourier-transform infrared (FTIR) characterization reveals the involvement of various functional groups in the adsorption process through hydrogen bonds and electron-donor-acceptor (EDA) interactions. X-ray diffraction (XRD) analysis confirms the presence of phases containing CO 3 2- ions, as well as elements such as Si and Fe, which contribute to the adsorption mechanism through hydrogen bonding and complexation, respectively. X-ray photoelectron spectroscopy (XPS) analysis further supports these interactions. Kinetic analysis shows rapid adsorption, which combines physical and chemical processes and leads to rapid attainment of equilibrium. This is due to the high affinity of WH-C450 for SMX, which allows for a fast and efficient adsorption process. Isothermal modeling reveals multilayer adsorption with favorable interactions. Thermodynamic analysis confirms the endothermic and temperature-dependent nature of the process. In addition, pH, adsorbent dose, and initial concentration are important in adsorption. Lower pH levels enhance cationic SMX adsorption, while higher adsorbent doses improve efficiency. Optimal conditions were identified by experimental design, enabling the establishment of a predictive model. Consequently, the SMX removal capacity is strongly correlated with the initial concentration. This research underscores the potential of WH-C450 for antibiotic removal in water treatment applications.4 3- ions, as well as elements such as Si and Fe, which contribute to the adsorption mechanism through hydrogen bonding and complexation, respectively. X-ray photoelectron spectroscopy (XPS) analysis further supports these interactions. Kinetic analysis shows rapid adsorption, which combines physical and chemical processes and leads to rapid attainment of equilibrium. This is due to the high affinity of WH-C450 for SMX, which allows for a fast and efficient adsorption process. Isothermal modeling reveals multilayer adsorption with favorable interactions. Thermodynamic analysis confirms the endothermic and temperature-dependent nature of the process. In addition, pH, adsorbent dose, and initial concentration are important in adsorption. Lower pH levels enhance cationic SMX adsorption, while higher adsorbent doses improve efficiency. Optimal conditions were identified by experimental design, enabling the establishment of a predictive model. Consequently, the SMX removal capacity is strongly correlated with the initial concentration. This research underscores the potential of WH-C450 for antibiotic removal in water treatment applications., Competing Interests: Declarations. Ethical Approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Cellulose nanocrystal (CNC)/silica hybrid aerogel (CSA) was synthesized from CNC and sodium silicate hybridization using the one-step sol-gel method under atmospheric drying. At a weight ratio of CNC to silica of 1:1, the obtained CSA-1 had a highly porous network, a high specific area of 479 m 2  g -1 , and a CO 2 adsorption capacity of 0.25 mmol g -1 . Then, polyethyleneimine (PEI) was impregnated on CSA-1 to improve CO 2 adsorption performance. The parameters governing CO 2 adsorption performance on CSA-PEI, such as temperatures (70-120 °C) and PEI concentrations (40-60 wt%), were investigated systematically. The optimum adsorbent (CSA-PEI50) exhibited an excellent CO 2 adsorption capacity of 2.35 mmol g -1 at 70 °C and a PEI concentration of 50 wt%. The adsorption mechanism of CSA-PEI50 was elucidated by analyzing many adsorption kinetic models. The CO 2 adsorption behaviors of CSA-PEI at various temperatures and PEI concentrations had the goodness of fit with the Avrami kinetic model, which can correspond to the multiple adsorption mechanism. The Avrami model also showed fractional reaction orders in a range of 0.352-0.613, and the root mean square error is negligible. Moreover, the rate-limiting kinetic analysis showed that film diffusion and intraparticle diffusion resistance controlled the adsorption speed and dominated the subsequent adsorption stages, respectively. The CSA-PEI50 also exhibited excellent stability after ten adsorption-desorption cycles. This study illustrated that CSA-PEI was a potential adsorbent for CO 2 capture from flue gas., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Plant extracts and bacterial biofilm are acknowledged to offer impressive corrosion-inhibitory activities. However, anticorrosive properties of their combination are still less reported. Thus, in the present study, we aimed to evaluate the corrosion inhibition efficiency of Saccharum officinarum bagasse (SOB) plant extract, Pseudomonas chlororaphis (P. chlororaphis), and Bacillus coagulans (B. coagulans) individually and in combination (SOB+P. chlororaphis) and (SOB+B. coagulans) using copper sheets in different acidic solutions (pH 5.5) and at three different temperatures (300 K, 305 K, and 310 K). The weight loss and electrochemical measurements were carried out to evaluate the corrosion rate and inhibition efficiencies. Alteration in the surface morphology of copper sheets was analyzed employing Fourier transform infrared (FTIR) spectroscopy, UV visible spectroscopy, scanning electron microscope (SEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX), and X-ray photoelectron spectroscopy (XPS). Amongst all, SOB extract alone exhibited the highest anticorrosive efficiency, whereas the combination of SOB with P. chlororaphis revealed excellent inhibition efficiency. Weight loss studies indicated that at 300 K, the combination of SOB extract with P. chlororaphis significantly reduces the corrosion rate up to 11.90% with the highest inhibition efficiency of 88.09%. However, with an increase in temperature, i.e. 310 K, the corrosion rate diminishes to 13.04% with inhibition efficiency of 86.95% for 500 µL concentration in HNO 3 solution. The combination of an SOB extract with P. chlororaphis displayed a maximum corrosion inhibition efficiency of 85.11% in the potentiodynamic polarization (PP) study and 88.23% in the electrochemical impedance spectroscopy (EIS), respectively and found in agreement with the efficiency obtained in the weight loss study. Later, the synergistic parameter (S Ɵ ) advocated that the SOB extract and P. chlororaphis do not interact mutually whereas ∆G° ads values suggested the physisorption of these agents on the copper plates follows Langmuir adsorption isotherm. The spectral analysis and SEM images of the copper plate revealed that the combination of SOB extract with P. chlororaphis forms a strong protective layer over its surface and prevents corrosion. In conclusion, the combination of SOB extract with P. chlororaphis holds impressive anticorrosive properties and may be explored further to attain their industrial utility., Competing Interests: Declarations. Ethics approval: Not applicable Consent to participate: Not applicable Consent for publication: All authors provide their consent for the publication. Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Terdizolamide phosphate (TZD), a second-generation oxazolidinone antibiotic with a long half-cycle, poses a potential threat to ecosystems and humans if present in water over an extended duration. Magnetic biochar (CF-biochar) loaded with CeFe 2 O 4 was firstly synthesized by microwave ablation-anaerobic carbonization using corn straw as raw material and Ce(NO 3 ) 3 and Fe(NO 3 ) 3 as modifiers. These modifiers were used as activators for peroxymonosulfate (PMS) and adsorbents for removing TZD. The maximum adsorption capacity of CF-biochar was up to 2869.44 mg g -1 , which was much higher than that of modified biochar. The CF-biochar/PMS system achieved 99.72% removal of TZD and accelerated the removal rate with good results. Results from quenching and electron spin resonance (ESR) tests showed that · O H and SO 4 · - played a major role in the oxidative degradation of TZD. Besides, they had a good removal effect on TZD among other co-existing anions. CF-biochar exhibited a smaller particle size, larger specific surface area, more abundant pore size, and high magnetic nature. The removal kinetics and removal isotherms were modeled to show that the adsorption of TZD by CF-biochar was a spontaneous, exothermic, physical multilayer adsorption process. Main driving force corresponded to electrostatic attraction and hydrophobic properties. Therefore, the CF-biochar/PMS system was an efficient, promising, and sustainable technology for removing TZD., Competing Interests: Declarations. Ethical approval: The research meets the ethical approval, including adherence to the legal requirements of the study country. Consent to participate: All the authors gave their consent to participate in the work. Consent for publication: All the authors gave explicit consent to submit the work to Environmental Science and Pollution Research. Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Plastics are widely used across various applications from packing to commercial products. Once discarded, they were subjected to environmental stresses, causing them to degrade into microplastics (MPs). These small, invisible pollutants pose a significant threat to aquatic ecosystems, gradually compromising the resilience and vitality of the natural environment. Moreover, MPs will act as carriers for other contaminants, for example, heavy metals (HMs). Although many studies have explored MPs and HMs independently, their combined behavior and interactions remain poorly understood. Understanding these interactions is increasingly important given rising pollution levels. MP formation and adsorption behavior are heavily influenced by factors such as UV aging, which remains unclear. In this study, both virgin and UV-aged MPs specifically PET and PP (the most widely used plastics globally) were examined in their interactions with copper (Cu 2+ ) solutions. Surface analysis techniques such as FTIR, SEM, XRD, and AAS were employed to compare the virgin and UV-aged MPs. The results revealed that UV-aged MPs exhibited high adsorption capacities for HMs compared to virgin MPs, which can be attributed to increased pore volume and oxidative degradation. Adsorption capacity differences at various concentrations showed up to a 20% increase, with UV-aged PET MPs displaying capacities ranging from 0.6 to 3.54 mg/g. Similarly, UV-aged PP MPs showed a 15% increase in adsorption capacity ranging from 1.51 to 4.25 mg/g. The present study provided the significant evidence on the behavior of MPs adsorption and underscores the need for further research on the long-term environmental impacts of aged MPs and their interactions with pollutants., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Numerous studies indicate biochar's nitrogen (N) adsorption capacity plays a crucial role in soil N retention. However, there is limited understanding on inorganic N adsorption mechanisms in biochar derived from aquatic weeds such as water hyacinth (WH). This study investigated ammonium-N (NH 4 + -N) adsorption capacities and mechanisms of WH biochar pyrolyzed at different pyrolysis temperatures of 400 °C, 600 °C, and 800 °C (BC400, BC600, and BC800, respectively). Results showed NH 3 -N adsorption was maximized (1.07-1.09 mg g - -N) adsorption capacities and mechanisms of WH biochar pyrolyzed at different pyrolysis temperatures of 400 °C, 600 °C, and 800 °C (BC400, BC600, and BC800, respectively). Results showed NH 4 -N adsorption peaked (0.80 mg g + -N adsorption was maximized (1.07-1.09 mg g -1 ) with BC400 at initial solution pH 7.0-9.0, while NO 3 -N followed well the Pseudo-second-order model in adsorption kinetics (R -  = 0.990-0.997 and 0.962-0.992, respectively). The Sips model accurately described the adsorption isotherms for NH -1 ) with BC800 at initial solution pH 5.0. Both NH 4 + -N and NO 3  = 0.992-0.999). The calculated maximum adsorption capacity for NH - -N followed well the Pseudo-second-order model in adsorption kinetics (R 2  = 0.990-0.997 and 0.962-0.992, respectively). The Sips model accurately described the adsorption isotherms for NH 4 + -N (R 2  = 0.994-0.999) and NO 3 -N adsorption capacity, respectively, with other ions with higher valence exhibiting higher inhibition effects (43%-97% and 44%-73%, respectively). Primary adsorption mechanism for NH - -N included cation exchange via oxygen-containing surface functional groups in BC400 and pore filling and surface struvite precipitation in BC800. Major adsorption mechanisms for NO 2  = 0.992-0.999). The calculated maximum adsorption capacity for NH 4 + -N and NO 3 - -N using Sips model was 11.2-16.8 mg g -1 and 0.693-4.99 mg g -1 , respectively. Co-existing cations and anions reduced NH 4 + -N and NO 3 - -N adsorption capacity, respectively, with other ions with higher valence exhibiting higher inhibition effects (43%-97% and 44%-73%, respectively). Primary adsorption mechanism for NH 4 + -N included cation exchange via oxygen-containing surface functional groups in BC400 and pore filling and surface struvite precipitation in BC800. Major adsorption mechanisms for NO 3 - -N included electrostatic interactions in BC400 and pore filling in BC800. These findings suggested that biochar derived from aquatic weeds possessed the same potential usefulness for soil N retention as biochar from other feedstocks, and that it might assist for further detailed considerations in other studies for biochar soil application., Competing Interests: Declarations. Consent to participate: Informed consent was obtained from all individual participants included in the study. Consent to publish: Written informed consent for publication of this paper was obtained from all authors. Ethical Approval. Not applicable. Competing interests: All authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest or non-financial interest in the subject matter or materials discussed in this manuscript., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Effluents containing antibiotics raise concerns due to their potential to promote or sustain bacterial resistance and disrupt essential cycles and processes critical to aquatic ecology, agriculture, and animal farming. Vancomycin is a glycopeptide antibiotic, recognized as the treatment for cases in which other antibiotics are unsuccessful. The efficient elimination of antibiotics plays a crucial role in managing antibiotic pollution. In this work, an ionic liquid-based magnetic activated carbon (IL@mAC) adsorbent was synthesized and utilized for removal of vancomycin in an aqueous solution. Parameters such as pH, dosage of adsorbent, contact time and antibiotic concentration were investigated. The data showed the efficient elimination of vancomycin in the solution. The maximum removal of vancomycin was obtained at pH 6. The optimum contact time and vancomycin concentration were found to be 30 min and 40 mg.L -1 , respectively for 0.6 g of IL@mAC in 50 mL sample solutions. Towards the removal of vancomycin, an adsorption efficiency of 83.4% was achieved for five subsequent cycles of vancomycin adsorption-desorption. The adsorption data for vancomycin fitted well with the Langmuir isotherm, and the maximum sorption capacity of IL@mAC was 132 mg.g -1 . Additionally, cytotoxicity studies indicated that the synthesized IL@mAC was non-toxic to normal Human umbilical vein endothelial (HUVEC) cells at concentrations ≤ 800 mg.L -1 . The use of this system facilitates the rapid and effective removal of vancomycin from wastewater through the application of an external magnetic field., Competing Interests: Declarations. During the preparation of this work the authors have not used any special generative AI and AI-assisted technologies. Ethical approval and consent to participate: This study does not include any human or animal subjects. Consent to publish: Not applicable. Institutional review board statement: The study protocol was approved by Zahedan University of Medical Sciences (Ethical code: IR.ZAUMS.REC.1399.517, https://lnkfwd.com/u/MFVnRGSN ). Conflict of interest: The authors declare that there are no conflicts of interest in this study., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In this study, water extract from Indian rosewood tree leaves was used to synthesize copper oxide nanoparticles (CuO NPs), further loaded on graphene oxide sheets to synthesize a novel nanocomposite (CuO@GO@IR). The maximum tetracycline removal was achieved at optimum conditions of pH 3, adsorbent dose 0.03g/50 mL, and 240 min contact time. The maximum adsorption capacity of the adsorbent was 769.23 mg/g. Experimental data was better fitted with the Freundlich isotherm and followed pseudo-second-order. The adsorption process was thermodynamically spontaneous and feasible. Nanocomposite has shown excellent regeneration efficiency with 0.1 M HCl as a desorbing agent. The overall performance of the nanocomposite suggests that it can be used as a promising adsorbent for treating antibiotics containing wastewater., Competing Interests: Declarations. Ethical approval: No prior ethical approval was necessary for the study. Consent to participate: No human subjects included in the study. Consent not required. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Water pollution because of the presence of heavy metals remains a serious worry. The present work demonstrates the exclusion of cobalt ion (or Co(II)) from water using novel and cost-effective biosorbents. Initially, the biosorbent was chemically modified using orthophosphoric acid and then subjected to calcination to result acid modified date seed biochar (AMDB). Three biosorbents (AMDB400, AMDB500, and AMDB600) were synthesized concerning different activation temperatures (400, 500, and 600 °C). The maximum biosorption of Co(II) was achieved on AMDB600 (149.5 mg/g), followed by AMDB500 (138.33 mg/g), and ADMB400 (129.17 mg/g). For all three biosorbents, the Co(II) removal remained effective within 50-100 min; later it reached saturation. The kinetic analysis suggested strong Co(II) adsorption on AMDB surfaces. The Co(II)-AMDB biosorption data fits well with Temkin isotherm, indicating the heterogeneity on the biosorbent surface and no interaction between adsorbed Co(II)-Co(II) species. The thermodynamic analysis suggested the exothermic and spontaneous adsorption. The intraparticle diffusion of Co(II) within the biosorbent was surface diffusion controlled, as characterized by pore volume and surface diffusion model. The biosorbent reusability was 88.7% after five adsorption-desorption cycles. Thus, presently synthesized biosorbent could be novel and cost-effective for Co(II) and other heavy metal elimination from water bodies., Competing Interests: Declarations. Ethics approval: No ethical approval is required for the present research. Consent to participate: The present research does not involve any human subjects or living organisms. Consent for publication: The participant has consented to the submission of the research to the journal. Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The enhancement effect of Ce modification on V 2 O 5 -WO 3 /TiO 2 catalysts at low temperatures was investigated for the selective catalytic reduction (SCR) of NO x with NH 3 (NH 3 -SCR). By adding 9% CeO 2 to 0.5%V 2 O 5 -3%WO 3 /TiO 2 catalyst, the low-temperature denitrification performance of Ce 9 V 0.5 W 3 Ti catalyst after Ce modification was significantly improved, achieving a NO conversion above 90% within a broad temperature range of 200-350℃, with catalytic activity comparable to that of 3% V 2 O 5 -3% WO 3 /TiO 2 . The catalysts were characterized by XPS, H 2 -TPR, NH 3 , and NO-TPD. The results indicated that the Ce additive could enhance the adsorption of NO x on Ce 9 V 0.5 W 3 Ti catalyst due to the synergetic interaction among the Ce and V, W species. The interaction between V and Ce also promoted the formation of V 5+ and Ce 3+ on the surface of the catalyst, which was conducive to enhancing the adsorption and oxidation capacity of the catalyst for NO. Additionally, the introduction of Ce led to a substantial deposition of nitrate species on the surface of the catalyst, especially the increase of nitrite species, which was beneficial to the NH 3 -SCR reaction process, resulting in a significant enhancement of the catalyst's low-temperature catalytic activity., Competing Interests: Declarations. Ethics approval and consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Leather manufacturing is the process of converting raw animal hides or skins into finished leather. The complex industrial procedures result in a tanning effluent composed of chemical compounds with potentially hazardous impacts on humans and ecosystems. Among the traditional and efficient wastewater treatments, adsorption is an effective and well-known approach, able to manage a wide range of contaminants from wastewater. Among the plethora of adsorption substrates used on an industrial scale, zeolites have traditionally shown remarkable performances. Differently from other types of adsorbents, zeolites can also work as cation exchangers, which can remove cationic contaminants without influencing the anionic content of the effluent and (in specific cases) also when the removal process is endothermic. Zeolites are minerals naturally present in the environment, but they can be also easily synthesized and modified to enhance their water remediation features. However, the removal efficiency of zeolites is strictly dependent on the type of target contaminant because its uptake capacity is linked to its chemical and physical characteristics, especially on the surface interlayer. This review intends to present a general description of the tannery process to understand the origin and characterization of tanning wastewater. The core of the study aims to approach the most significant studies about zeolite applications in the removal of tanning contaminants. Drawbacks of the reviewed literature are further discussed, and some potential future research content is eventually revealed by identifying the issues that need further investigation., Competing Interests: Declarations. Competing interests: The authors declare no competing interests. Disclaimer: This manuscript reflects only the authors’ views and opinions, neither the European Union nor the European Commission can be considered., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This study presents a novel, eco-friendly method for removing methyldiethanolamine (MDEA) from wastewater, addressing its environmental impact and elevated chemical oxygen demand (COD) from gas refineries. We employed two wetland plants, Phragmites australis and Typha latifolia, utilizing a hydroponics approach to assess MDEA removal efficiency. Wastewater samples from the Ilam gas refinery in Iran were tested at varying initial concentrations (50 to 1600 ppm) over three consecutive 7-day periods, with a 1-day rest interval. Key factors influencing MDEA absorption-contact time, initial effluent concentration, and pH-were systematically analyzed. Results indicated a significant decrease in pH, COD, and MDEA concentration during the first four days. Kinetic modeling employed pseudo-first-order (PFO) and pseudo-second-order (PSO) models, alongside adsorption isotherms (Langmuir, Freundlich, Temkin, Dobinin-Radeshkovich, and Louis), to evaluate MDEA absorption capacity. The Langmuir isotherm best described the absorption characteristics of both plants. Maximum adsorption capacities were recorded for P. australis at 1.181, 2.018, and 3.77 mg/L across the experimental periods, while T. latifolia showed values of 0.779, 1.099, and 2.99 mg/L. Kinetic analysis favored the pseudo-second-order model for both species. Our findings suggest that P. australis is the more effective candidate for phytoremediation of MDEA in wastewater treatment applications., Competing Interests: Declarations. Ethical approval: This article does not contain any studies with human participants or animals performed by any of the authors. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This study explores the use of functionalized manganese oxide (K-MnO 2 -NH 2 ) for the removal of hexavalent chromium (Cr(VI)) ions, a highly toxic heavy metal contaminant, from wastewater. The synthesis of K-MnO 2 -NH 2 was achieved through a two-step process, followed by comprehensive characterization using various analytical techniques, which confirmed the material's formation as a pure phase. The K-MnO 2 -NH 2 exhibited exceptional chromium removal efficiency, achieving up to 90% (4.53 mg/g) of Cr(VI) removal at pH 2. This high efficiency is attributed to the incorporation of amine groups via functionalization with 3-aminopropyltriethoxysilane (APTES), which introduces active sites with a strong affinity for Cr(VI) ions. Kinetics studies indicated that a chemical reaction governs the adsorption process, while thermodynamic data suggested it to be exothermic, and thermodynamic data reveal the process to be exothermic. The Freundlich isotherm best described the adsorption behavior. The Cr(VI) adsorption capacity of K-MnO 2 -NH 2 was determined to be 45.17 mg/g. K-MnO 2 -NH 2 effectively removed Cr(VI) from industrial wastewater, achieving a removal efficiency of around 41% (25.5 mg/g) and visible discoloration showing excellent reusability, maintaining over 80% removal efficiency after five cycles without requiring regeneration. This innovative approach highlights the potential of K-MnO 2 -NH 2 as a sustainable and effective solution for Cr(VI) removal in environmental remediation and water purification., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

A sustainable biosorbent, silver nanoparticles-decorated coffee-ground waste (CWAg), was synthesized through a simple in-situ reduction method. CWAg is extensively characterized via SEM-EDX, PZC, FTIR, XRD, HR-TEM, and XPS analyses. The biosorbent was tested to remove chromium (Cr(VI)) and methylene blue (MB) from wastewater, and its antibacterial properties was evaluated. CWAg demonstrated efficient sorption efficiencies, achieving ⁓149.9 mg/g at 323 K and pH: 2.0 for Cr(VI) and ⁓113.4 mg/g at 293 K and pH: 6.0 for MB, at a biosorbent dose of 1 g/L. The equilibration times were 90 and 120 min for Cr(VI) and MB, with half-sorption times (t HST ) of 9.2 and 13.9 min, respectively. The sorption mechanisms were successfully fitted with Sips isotherm and Pseudo-second-order models. Simultaneous sorption of MB and Cr(VI) at pH 2.0 exhibited antagonism, while a synergistic effect was observed at pH 6.0. Desorption and regeneration were achieved using NaOH and HCl solutions for Cr(VI) and MB, respectively. The efficiencies were just reduced by 9-13%. Finally, CWAg exhibited remarkable effectiveness for removing Cr(VI) from complex tannery effluent. Moreover, CWAg demonstrated positive antibacterial effects against both Gram-positive and Gram-negative bacteria, surpassing raw coffee-ground waste, underscoring the significant role of silver nanoparticles in enhancing bacterial inhibition., Competing Interests: Declarations. Ethics approval and consent to participate: Not applicable. Consent for publication: All authors have read, consented, and agreed to the published version of the manuscript. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

To investigate the modification of Pb 2+ adsorption of the functional groups of Cladophora rupestris (C. rupestris) biomass by gamma radiation ( 60 Coγ-ray), the interface structure, chemical properties, adsorption behaviors, and Pb 2+ adsorption mechanisms of C. rupestris biomass were investigated after irradiation with varying doses of 60 Coγ-ray. The results indicate that 60 Coγ-ray significantly changed the surface characteristics and interfacial chemistry of the C. rupestris biomass.This led to fracturing and fragmentation that produced a larger specific surface area and more abundant pore structure, increasing the electronegativity in the C. rupestris biomass. The theoretical Pb 2+ adsorption capacity increased significantly (2.6-2.9 times) after 60 Coγ-ray irradiation. 60 Coγ-ray caused preferential degradation of protein components in the dissolved organic matter of the C. rupestris biomass, and protein deamination increased the absorption sites of cations. In the C. rupestris biomass, 60 Coγ-ray altered the elemental composition and functional groups, particularly the carbon- and oxygen-containing functional groups, to improve Pb 2+ adsorption. In conclusion, 60 Coγ-ray can activate the functional groups of C. rupestris biomass and improve their Pb 2+ adsorption sites. This study provides new insight into modification of biomass materials for enhanced removal of heavy metals from waterbodies., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: We consent to participate this manuscript. Consent for publication: We consent to publish this manuscript. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In this study, boron-doped magnetic mesoporous silica nanocomposite was prepared through the hydrothermal synthesis procedure followed by post modification with -NH 2 groups. The higher surface area, more ordered mesoporous structure, and higher surface charge density obtained by boron doping and amino functionalization contributed to the use of nanocomposite for multipurpose application functions. When used as an adsorbent for light green (LG) anionic dye, boron-doped nanocomposite exhibited higher adsorption capacity (105.80 mg/g) compared to undoped nanocomposite (72.23 mg/g), while when used as a drug carrier for Doxorubicin (DOX), a sufficient drug loading capacity (48.0 mg/g) was obtained, which is also higher than that of undoped nanocomposite (30.3 mg/g). In terms of LG adsorption, the effects such as initial concentration, adsorbent dosage, time, pH, and temperature on the adsorption properties were investigated in detail. Adsorption kinetics, isotherms, thermodynamics, and reusability are discussed. The existence of small quantity of boron doping enhanced the surface charge density from 0.0393 to 0.2854 C/m 2 , which resulted in higher adsorption capacity for LG adsorption dominated by electrostatic attraction, and led to formation of silanol holes together with the -OH and -NH 2 functional groups, which resulted in higher drug loading capacity for DOX adsorption dominated by hydrogen bonding. This promising result provides that boron-doped and -NH 2 grafted magnetic mesoporous silica material can function as multipurpose adsorbent for various environmental applications., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This research utilized tetraethylenepentamine-functionalized HY cubic zeolite as an adsorbent to effectively remove heavy metals from aqueous solutions. The adsorbent was characterized using FT-IR, XRD, TGA, FE-SEM, and EDS-MAP techniques. The synthesis aimed to optimize and evaluate the removal efficiency of Pb(II), Cr(III), Co(II), and Cu(II) from aqueous solutions by investigating key parameters, including initial pH, concentration, adsorbent dosage, and contact time. The results indicate that the highest adsorption capacities for each metal follow the order: Pb(II) > Cr(III) > Co(II) > Cu(II), with respective percentages of 99.7%, 98.2%, 95.1%, and 92.4%. Analysis of the batch systems reveals that the equilibrium data for Pb(II), Cr(III), Co(II), and Cu(II) align well with the Langmuir and Freundlich isotherms also show a good fit, with correlation coefficients (R 2 ) higher than 0.9335 and 0.9478, respectively. The maximum adsorption capacities (181.82, 175.44, 169.49, and 158.73 mg/g) reflect the nature of the adsorption process. Kinetic studies for Pb(II), Cr(III), Cu(II), and Cu(II) yielded correlation coefficients (R 2 ) higher than 0.9971. These high R 2 values suggest that the experimental data closely fit a pseudo-second-order model, indicating a two-step adsorption mechanism. Heavy metal removal is attributed to ion exchange and chemisorption within the zeolite pores, involving interactions with nitrogen lone pairs., Competing Interests: Declarations. Ethical approval: The authors have completed the manuscript with ethical standards. Consent to participate: Not applicable. Consent to publish: Authors are satisfied to publish their research work in Environmental Science and Pollution Research. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

It is important to accomplish both photocatalytic efficiency and adsorption capacity in the catalyst to produce a highly effective photocatalyst for complete dye removal from wastewater. In the current investigation, TiO 2 and fly ash-TiO 2 composites (0.5-5 wt%) were fabricated by sol-gel and wet-impregnation process, and their catalytic performance was evaluated for the effective adsorption and photocatalytic degradation of fuchsin blue dye. The catalysts were characterized by XRD, UV-DRS, SEM, EDS, RAMAN spectroscopy, and N 2 adsorption analysis Adsorption and degradation studies were conducted to investigate factors such as pH (2 - 10), adsorbent dose (1-9 mg), contact time (30-180 min), and initial adsorbate concentration (5-30 mg/L) to eradicate fuchsin dye from water. The 5 wt% fly ash-TiO 2 catalyst showed a maximum capacity for adsorption of 20.32 mg/g and 76% removal of fuchsin dye. The Langmuir isotherm model fitted well to the experimental data, whereas the adsorption process obeyed pseudo-first-order kinetics. When exposed to UV light, a 5 wt% fly ash-TiO 2 composite demonstrated maximum photocatalytic degradation of 88% after 180 min, followed by a pseudo-first-order kinetic model. The catalyst was easily reusable for five cycles without losing dye removal effectiveness., Competing Interests: Declarations. Ethics approval: This work adhered to all ethical prerequisites for research publications. There were no experiments on animals carried out. Consent to participate: This work was not based on any research on humans. Consent for publication: All authors actively engaged in this study, provided contributions to its content, and received updates on the progress of the article preparations. Conflict of interest: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Cost-effective and environmentally friendly sorbents were created for capturing CO 2 by incorporating monoethanolamine (MEA) and tetraethylenepentamine (TEPA) onto a microporous activated carbon (AC) material. The application of a KOH reagent enhanced the surface area and pore volume of the carbon material. The BET, SEM, EDX, and FTIR techniques were employed to analyze the structural and surface properties of the developed samples. Raw AC possessed the highest surface area and largest micropore volume equal to 786 m 2 /g and 0.33 cm 3 /g, respectively. The amine impregnation increased the nitrogen content of the carbon material, but it also significantly reduced the BET surface area and total pore volume, which are primarily responsible for physically adsorbing CO 2 towards ACs. The CO 2 adsorption performance of the raw and impregnated ACs was experimentally evaluated using thermogravimetric analysis (TGA) at different adsorption temperatures (25 and 50 °C) and CO 2 concentrations (10 and 90 vol.%). The findings demonstrated that the raw AC exhibited the highest capacity for CO 2 adsorption. Specifically, at a temperature of 25 °C and pressure of 1 bar (10 vol.% CO 2 , N 2 balance), the raw AC achieved an uptake of 1.2 mmol/g, which was 60.3% and 79.3% higher compared to the CO 2 uptake of MEA-AC (0.5 mmol/g) and TEPA-AC (0.3 mmol/g), respectively. It is surprising that the combined uptake of CO 2  + H 2 O increased by 12.5 and 23.4 wt.% (equivalent to 7 and 13 mmol/g) for MEA-AC and TEPA-AC, respectively, when humid flue gas was taken into account under the conditions of 50 °C, with 10 vol.% CO 2 , 4 vol.% H 2 O, and N 2 balance. These results indicate that the presence of H 2 O facilitates the chemisorption of CO 2 by the novel and highly promising carbon-based sorbent prepared in this study, leading to an increased capacity for adsorbing CO 2 under water vapor containing flue gases., Competing Interests: Declarations. Ethics approval: This is not applicable. Consent to participate: All authors consent to participate. Consent for publication: All authors consent to publish. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This study introduces a novel and environmentally friendly method for developing a cross-linked chitosan-Ocimum basilicum leaves-ZnO (ChOBLZnO) composite membrane, specifically designed for the adsorption of permanganate ions (MnO 4 -) from wastewater. Various characterization techniques, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) surface area analysis, were employed to confirm the membrane's synthesis quality, structural integrity, and surface properties crucial for adsorption. The BET analysis revealed a surface area of 228.64 m 2 /g, indicating a highly porous structure. The membrane exhibited a high adsorption capacity of 142.8 mg/g and an outstanding removal efficiency of 98.5%. The adsorption kinetics were best described by the pseudo-second-order model, with a correlation coefficient (R 2 ) of 0.998, while the Freundlich isotherm model provided the most accurate fit for the adsorption behavior, with an R 2 of 0.995. Thermodynamic studies indicated that the adsorption process is spontaneous and endothermic, with negative Gibbs free energy and positive enthalpy and entropy values. Reusability tests showed that the ChOBLZnO composite membrane maintained a high removal efficiency across five cycles, with minimal performance loss. These results demonstrate the ChOBLZnO composite membrane's potential as an efficient and sustainable solution for wastewater treatment, offering both high efficiency and durability., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Environmentally hazardous radioactive isotopes of iodine may be released from a nuclear power plant as a by-product of uranium fission. The efficient and safe capture of volatile radioiodine is of great significance in the history of nuclear power plants. Due to its high volatility and carcinogenic characteristics, elimination of iodine gas (I 2 ) from air is the need of the hour from an environmental and health point of view. In this work, the trapping of molecular iodine has been studied using porous adsorbents such as activated carbon (AC) and activated carbon impregnated with metals or triethylenediamine (TEDA). Impregnated activated carbons (IACs) chemically react with iodine through SN 2 mechanism. The physicochemical and structural characterization of raw activated carbon (RAC) and impregnated activated carbons (IACs) was done by AAS, SEM, EDX, BET, and XRD. The finding of the breakthrough experimental adsorption showed that the gaseous iodine (50 ppm) equilibrium adsorption capacity of the raw AC before and after impregnation increased from 180 to 1044 mg/g mL at a condition of 60 °C. Furthermore, metal IAC was highly adsorbent at high temperatures (80 °C) due to its stability, and it adsorbed up to 576 mg/g mL iodine at a maximum. The breakthrough study examined that the adsorption capacity of iodine enhanced up to 19% for metal and 26% for metal-TEDA IAC as compared to RAC. Adsorption equilibrium data were well described by the Langmuir model, and the kinetics study was demonstrated by the second-order model. Thermodynamic parameters demonstrated that this is an exothermic and spontaneous reaction. This study explored the parameters of a filter such as adsorption capacity and saturation time at which no more pollutant gas can be captured. Finally, the findings demonstrate that these adsorbents may be capable of adsorbing large amounts of gaseous iodine., Competing Interests: Declarations. Ethical approval: We confirm that this work is original and has neither been published nor is currently considered for publication elsewhere. We confirm that the co-author acknowledges her participation in conducting the research leading to this manuscript and has agreed to its submission to be considered for publication. The research meets the ethical guidelines, including adherence to the legal requirements of the study. Per the journal’s style and format requirements, we have prepared the manuscript, including figures and tables. Consent to participate: All authors have agreed to contribute to this study. Consent for publication: The authors agree to publish. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Norfloxacin (NOR) is frequently detected in various water bodies and has the potential to promote the proliferation of NOR-resistant bacteria/genes in the environment. Efficiently removing residual NOR and NOR-resistant bacteria from contaminated water is critical to mitigating their environmental risks. This study investigated the ability of two common clay minerals, kaolinite and montmorillonite, to remove NOR and NOR-resistant bacteria from five different water environments (ultrapure water, simulated and real freshwater, and simulated and real seawater) and explored the underlying removal mechanisms. The results showed that both clays adsorbed NOR according to a pseudo-first-order kinetic model. In simulated and actual freshwater and seawater, the adsorption of NOR by kaolinite was 0.199, 0.120, 0.094, and 0.010 mg g -1 , while montmorillonite adsorbed NOR at significantly higher levels, with values of 2.880, 2.208, 0.433, and 0.067 mg g -1 , respectively. The primary mechanisms of adsorption included electrostatic interactions, cation exchange, and cation bonding and bridging. In addition to NOR sorption, culture tests revealed that montmorillonite exhibited significant antibacterial activity against NOR-resistant bacteria, achieving an inhibition ratio of 83.84 ± 4.01% when the initial concentrations of bacteria and montmorillonite were 1.68 ± 1.00 × 10 5  CFU·mL -1 and 40 mg mL -1 , respectively. Remarkably, montmorillonite maintained its high sorption capacity and antibacterial activity even after multiple reuse cycles. These findings highlight the promising application potential of montmorillonite, particularly in terms of its storage and long-distance distribution capabilities, making it an effective material for removing both NOR and NOR-resistant bacteria from the environment. However, it is important to note that under estuarine conditions, clay-bound NOR could be released if water quality changes. Therefore, we conclude that strategies to degrade and remove antibiotics adsorbed onto clay minerals should be developed to prevent the release of antibiotics when clay particles enter the ocean, thus avoiding further environmental contamination., Competing Interests: Declarations. Ethics approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In this work, pellet-type carbon xerogel adsorbents (CXCs) were synthesized through sol-gel polymerization of resorcinol (R) and formaldehyde (F) using Cs 2 CO 3 (Cs) as a catalyst for the removal of sulfamethoxazole (SMX), a hazardous water pollutant. The R/Cs ratio was varied at 100, 500, 1000, and 2000 (denoted CXCs100, CXCs500, CXCs1000, and CXCs2000), resulting in CXCs with a well-defined hierarchical porous structure composed of interconnected spherical particles. Increasing the R/Cs ratio led to larger spherical particle sizes, with pore diameters ranging from 60.7 to 126.6 nm, providing accessible and low flow resistance macroporosity. The maximum adsorption capacity was achieved in the CXCs100 sample (87.8 mg/g), which decreased with increasing R/Cs ratios due to a reduction in total pore volume and meso and macropore areas, indicating that adsorption occurred in macropores and wide mesopores, driven by π-π dispersive interactions. CXCs500 emerged as the optimal adsorbent, with a favorable adsorption capacity (72.0 mg/g) and adequate rigidity (315.9 MPa) to prevent adsorbent breakdown. The adsorption capacity decreased with increasing pH due to electrostatic interactions, and increased with temperature, indicating an endothermic process., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Water softening is a treatment process required to remove calcium (Ca(II)) and magnesium (Mg(II)) cations from water streams. Nanocomposites can provide solutions for such multiple challenges and have high performance and low application costs. In this work, a multimetallic cobalt, nickel, and copper 2-aminoterephthalic acid metal-organic framework ((Co/Ni/Cu-NH 2 BDC) MOF) was synthesized by a simple solvothermal technique. This MOF was supported on an Egyptian natural zeolite ore and was used for the adsorption of Ca(II) ions for water-softening applications. The adsorbent was characterized using Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), N 2 adsorption-desorption isotherms, and zeta potential measurements. The adsorption isotherm data for the prepared adsorbent toward Ca(II) were best fit using the Redlich-Peterson model and showed a maximum adsorption capacity of 88.1 mg/g. The adsorption kinetics revealed an equilibrium time of 10 min, which was best fit using the Avrami model. The intermolecular interactions of Ca(II) ions with zeolite and MOF were investigated by Monte Carlo simulations, molecular dynamics simulations, and FTIR and XRD analyses. The adsorption sites in the zeolite structure were oxygen atoms, while those in the MOF structure were amine nitrogen atoms. The Ca(II) ions are coordinated with the solvent molecules in both structures. Finally, the in vitro cytotoxicity of this nanocomposite was assessed, revealing viability levels of 74.57 ± 2.1% and 21 ± 2.79% for Vero and African green monkey kidney and human liver (HepG2) cells, respectively. Cytotoxicity assays help assess the environmental impact of these materials, ensuring that they do not harm aquatic organisms or disrupt ecosystems. Thus, this study demonstrated the valorization of MOF/zeolite as a valuable and industry-ready adsorbent that can appropriate Ca(II) contaminants from aqueous streams., Competing Interests: Declarations. Ethics approval and consent to participate: This study is not applicable to human or animal studies. The article does not include any studies on human participants or animals conducted by any of the authors. Consent for publication: The authors confirm: • That the work described has not been published before; • That it is not under consideration for publication elsewhere; • That its publication has been approved by all coauthors. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

A magnetic nanocomposite adsorbent, comprised of macroporous iron oxide/manganese oxide (α-Fe 2 O 3 /Mn 2 O 3 ), is prepared, characterized, and used for lead(II) removal from both industrial wastewater and leachate of electronic waste. The synergistic interaction between iron oxide and manganese oxide significantly enhances the adsorption performance. The surface characteristics and structural composition of the nanocomposite are examined using high-resolution transmission microscopy, X-ray spectroscopy, and Brunauer-Emmett-Teller methods. Under optimized conditions, the present method offers a significantly high adsorption capacity (377.5 ± 8.9 mg.g -1 ), short contact time (10 min), and an excellent removal efficiency (98.0 ± 0.9%) compared with most of the previously suggested methods. The adsorption kinetics of Pb(II) on the nanocomposite surface follows pseudo-second-order kinetics and exhibits a good fit with the Dubinin-Radushkevich (D-R) model. These findings highlight the applicability of the α-Fe 2 O 3 /Mn 2 O 3 magnetic nanocomposite as a promising efficient adsorbent for the rapid removal of lead(II) from hazardous wastewater. Moreover, the proposed nanocomposite adsorbent exhibits remarkable stability and can be easily isolated from the test sample solution for subsequent reuse. The efficacy of the developed adsorptive removal procedure is confirmed by achieving a complete lead(II) ion removal from some industrial wastewater discharged from lead battery factories and from the leachate of electronic waste., Competing Interests: Declarations. Ethical approval: All experiments adhered to the guidelines set forth in the Declaration of Helsinki (1964) and the Clinical Medical Research Regulation Act of 2020. Approval was granted by the Ethical Committee (EC) of the Faculty of Science, Ain Shams University, Cairo, Egypt. Consent to Participate: Not applicable. Consent for Publication: Not applicable. Competing of Interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This study evaluates the adsorption performance of cobalt ferrite (CoFe 2 O 4 )-based magnetic nanoadsorbents (CF-MagNa) for the removal of triiodide ions ( I 3 - ) from iodinated water. The crystalline structure and phase purity of the synthesized material were confirmed via X-ray diffraction (XRD), which determined a crystallite size of 42 nm and a specific surface area of 26.98 m 2 /g. Field emission scanning electron microscopy (FESEM) revealed a porous morphology conducive to enhanced adsorption. The ferromagnetic properties of CF-MagNa were characterized using vibrating sample magnetometry (VSM), which demonstrated a saturation magnetization (σ s ) of 74.98 emu/g, a remanent magnetization (σ r ) of 29.82 emu/g, and a coercivity (H c ) of 1304 Oe, significant magnetic separation potential. Batch adsorption experiments revealed a 61.6% reduction in I 3 - concentration at a CF-MagNa dosage of 2 mg/mL. Adsorption isotherms were analyzed, with the Langmuir model yielding a maximum adsorption capacity (Q max ) of 13.641 mg/g and a Langmuir constant (K L ) of 0.00996 L/mg. The Freundlich model provided a capacity factor (K F ) of 1.892 mg/g and a heterogeneity factor (n F ) of 1.805 L/mg, while the Temkin model yielded a heat of adsorption (B) of 3.404 J/mol and a Temkin constant (K T ) of 0.743 L/g. The Dubinin-Radushkevich (D-R) isotherm demonstrated the highest correlation (R 2  = 0.97), with a maximum adsorption capacity of 8.28 mg/g. These results highlight CF-MagNa's efficacy as a potential adsorbent for water treatment, with promising applications in environmental remediation and sustainable water purification technologies., Competing Interests: Declarations. Ethical approval: This manuscript does not involve any animal or human studies. No experiments involving live subjects were conducted, and no identifiable human images or data are included. As such, ethical approval is not applicable to this work. Consent to participate: This study does not involve human participants; therefore, consent to participate is not applicable. Consent to publish: All authors have provided their consent for the publication of this manuscript. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Being able to cause eutrophication, a severe ecological problem that leads to the demise of aquatic animals, excessive phosphate in water bodies, has been a threat to the environment. Aiming to remove phosphate from wastewater in rural areas, adsorption is a promising method. In this study, a novel phosphate adsorbent, SEP-La, was synthesized by doping lanthanum into sepiolite. Characterization and batch adsorption experiments were performed. Lanthanum was loaded on sepiolite through hydrogen bond as forms of peroxides, and it greatly enhanced the adsorption capacity of sepiolite, reaching 135.78 mg/g. Pseudo-second-order kinetic model described the adsorption kinetics the best, indicating a chemisorption process. An endothermic yet spontaneous adsorption process was revealed by the fitting of the Langmuir isotherm model. The adsorbent exhibited great tolerance to pH change and interference ions. The remaining 67.82% of the original performance after 6 cycles of adsorption-desorption demonstrated its robust recyclability. Its real application potential was also manifested through column experiments using locally collected real wastewater and was able to treat 2072 mL of water per gram of adsorbent, which represents a significant milestone in translating theory into practice. FT-IR, XRD, and XPS were performed to prove that its mechanism involved electrostatic interaction and ligand exchange. This work provides an affordable while auspicious phosphate adsorptive material with the potential to effectively address the issue of excessive phosphate in water at a low cost., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

A promising water treatment method involves using biomass-derived activated carbon (AC) to remove emerging pollutants from wastewater due to its adsorption capacity, cost-effectiveness, and sustainability. Notwithstanding, the existing literature lacks comprehensive studies that specifically focus on removing contaminants in water by comparing the effectiveness of adsorption and photocatalytic degradation methods. Additionally, there is not much emphasis on analyzing the combined processes of adsorption-photocatalytic degradation utilizing AC. Herein, this paper investigates the intricacies of adsorption-photocatalytic degradation mechanisms and contributing variables in the enhancement of performances using biomass-derived AC. Furthermore, this review paper presents a comprehensive examination of different biomass sources employed in the synthesis of AC. It also discusses the diverse techniques utilized for the fabrication of AC, including physical and chemical activation methods. Finally, the shortcomings and future prospects of biomass-derived AC have been addressed. This study offers significant insights for the development of future biomass-derived AC, with the goal of improving their efficiency and expanding their uses in wastewater treatment., Competing Interests: Declarations. Ethics approval: Not applicable. Consent to participate: All participants in the study provided informed consent prior to their involvement. Consent for publication: All participants have provided their consent to publish the data collected during the study. Competing interests: The authors declare no competing interest., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In this article, the multifunctional behavior of novel, efficient, and cost-effective humic acid-coated nanoceria (HA@CeO 2 NPs) was utilized for the sorptive removal of U(VI), Cr(VI), and F - ions at different conditions. The production cost of HA@CeO 2 was $19.28/kg and was well characterized by DLS, FESEM, HRTEM, FTIR, XRD, XPS, and TGA. Batch adsorption study for U(VI) (at pH ~ 8), Cr(VI) (at pH ~ 1), and F - (at pH ~ 2) revealed that the maximum percentage of sorption was > 80% for all the cases. From the contact time experiment, it was concluded that pseudo-second-order kinetics followed, and hence, the process should be a chemisorption. The adsorption study revealed that U(VI) and Cr(VI) followed the Freundlich isotherm, whereas F - followed the Langmuir isotherm. Maximum adsorption capacity for F - was 96 mg g -1 . Experiments in real water suggest that adsorption is decreased in Kaljani River water (~ 12% for Cr(VI) and ~ 11% for F - ) and Kochbihar Lake water (25.04% for Cr(VI) and 20.5% for F - ) because of competing ion effect. Mechanism was well established by the kinetic study as well as XPS analysis. Because of high adsorption efficiency, HA@CeO 2 NPs can be used for the removal of other harmful water contaminants to make healthy aquatic life as well as purified drinking water., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: The authors declare consent to participate. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

To overcome the stringent regulations in the usage of chromium salts and dye-rich effluent let out by the tanning industry, a sustainable way of leather processing has been demonstrated utilizing amine pendant metal-organic frameworks (MOF) UiO-66-NH 2 along with glyoxal. It was found that an offer of 8% (w/w) MOF along with 6% (w/w) glyoxal increased the shrinkage temperature of the leathers to 89 ± 2 °C with exhaustion of MOF up to 84.3 ± 1.5%. The presence of cationic amine sites in the MOF aided in the fixation of anionic post-tanning agents and improved the adsorption of dyes from 74.3 ± 2.5% in the case of conventional leather to 91.8 ± 1.7% for experimental leather. In comparison to chrome-tanned leather, the experimental leathers were rated the highest in terms of dye fastness concerning rubbing action and against perspiration, showcasing the washable properties and better affinity and irreversible binding of dyes to the leather matrix. Mechanism studies through XPS spectroscopy revealed the interaction between the acidic amino acids of collagen and free zirconium metal sites and the imine linkage between amine pendants of MOF and basic amino acids of collagen protein. Further, the BOD 5 /COD ratio of 0.36 confirmed the better treatability of the wastewater emanating from the proposed process making it a sustainable tanning system. Thus, the combination of amine pendant MOFs with dialdehyde can be a promising strategy for the development of robust chrome-free leathers with excellent functional properties., Competing Interests: Declarations. Ethics approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The recovery of Co(II), Mn(II), Ni(II), and Cu(II) from black mass e-waste solutions through cellulose nanofibers (CNFs) and nanocrystals (CNCs) was investigated. These materials were synthetized by TEMPO-oxidation followed by high-pressure homogenization, and acid hydrolysis, respectively. The NC characterization included the measurement of consistency, cationic demand, carboxylic content, dissolved amorphous cellulose, and transmittance at λ = 600 nm. These parameters revealed a high transmittance of the NC solutions and a large presence of anionic groups on the surface. The high surface area and charge of the NC justify their high interaction with the cationic metals. Results indicate that short contact times (even 1 min) and low sorbent doses (10 mg/L) at acidic pHs (2 to 4) implied remarkable sorption capacities in most cases with more than 1 g/g of sorption capacity of Co(II), Mn(II), and Cu(II) in single-step sorption tests. Such levels of sorption capacities exceed by at least one order of magnitude most of the literature values of metal recovery applying cellulosic materials. Isotherm modeling through a combination of Langmuir and Freundlich models suggested that both sorption and surface precipitation occurred. A novel procedure following multiple-step batch operation was applied for Mn(II) sorption. This new method was applied as a five-step process, leading to a fourfold and 18-fold increase of sorption capacity onto CNCs and CNFs, respectively, compared to the single-step process. Therefore, this process shows an innovative way to implement the multiple-step batch sorption with NC as an efficient and environmentally friendly solution for critical metal recovery from e-waste leachates., Competing Interests: Declarations. Ethical approval: This work does not contain any research involving humans or animals. Consent to participate: The work described has not been published before, that it is not under consideration for publication anywhere else, and that written informed consent was obtained from individual or guardian participants. Consent for publication: The publication consent was obtained from all co-authors. Competing interests: The authors declare that one of the co-author, Prof Angels Blanco, is editorial board member of the journal. The authors have no relevant financial or non-financial interests to disclose., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Metal ion adsorption using agro-industrial residues has shown promising results in remediating contaminated waters. However, adsorbent effectiveness relies on their properties, often necessitating processing for modification. Considering this, plasma treatment is effective in modifying material surfaces physically and chemically. This study investigated the modification of sugarcane bagasse (SB) using plasma treatment and evaluated its efficacy as a novel adsorbent for mercury removal from aqueous solutions. SB underwent low-temperature plasma treatment with sulfur hexafluoride (SF 6 ) as the working gas, varying treatment times (2, 30, and 60 min), and fixed powers (80, 190, and 300 W) at 16 Pa pressure. Characterization via SEM/EDS, FTIR, XPS, and pHpzc revealed significant structural changes like increased in porosity and alteration in proportion atomic. Additionally, the successful incorporation of fluorine was confirmed in all treatment conditions, while sulfur was detected in only some samples. Amongst the tested conditions, the SB treated with 300 W for 60 min demonstrated the highest mercury removal efficiency, achieving an impressive 83.67% removal rate compared to untreated SB, which yielded only 57.95%. The adsorption mechanism exhibited both physical and chemical behavior, with chemisorption being the dominant process. The Freundlich model provided the best fit to the experimental data, with an R 2 value of 0.97. In conclusion, plasma treatment can be a promising alternative for improving the physical and chemical characteristics of SB adsorbents, thereby improving their efficiency in removing mercury from aqueous solutions., Competing Interests: Declarations. Ethics approval: Ethical approval was not required due to this study did not involve human participants and/or animals. Consent to participate: Informed consent was obtained from all individuals who participated in the research. Consent to publish: All authors have given their consent for the publication of this article. Competing interests: The authors have no relevant financial or non-financial interests to disclose., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Biomass-derived biochar has enormous potential for sustainable and low-cost treatment of lead-contained wastewater. In this study, corncob and cow dung-derived biochar were prepared. The increase in pyrolysis temperature could improve the porous structures, surface area, functional groups and alkalinity, and further provide a higher Pb 2+ capacity in both biochars. Cow dung biochar performed better than corncob for its higher inorganic mineral content and more alkaline surface. Among them, CDB-600 performed the Langmuir maximum capacity of 357.1 mg/g, with a high surface area of 144.3 m 2 /g; ion exchange and precipitate were the main adsorption mechanisms. After further MgO modification, the M-CDB displayed a high surface area of 166 m 2 /g, and ion exchangeability and precipitate-promoting effects were improved. M-CDB performed a Langmuir maximum capacity of 833.3 mg/g. The pHpzc was found to be 10 and the adsorbents portray a very good Pb 2+ adsorption selectivity among coexisting ions in the solution. The adsorption process was found to be endothermic, feasible, spontaneous and chemisorption. The fixed lead on CDB-600 was stable in water. The immobilized lead could be desorbed by acid wash. CDB-600 performed better in terms of sustainability in use, which could support its continuous application ability., Competing Interests: Declarations. Ethical approval: This manuscript was only submitted to Environmental Science and Pollution Research. All the research protocols were observed. The authors make sure they have permission for the use of all the information and tools necessary for the accomplishment of this research. The authors confirmed that this research’s contents and conclusions do not violate moral ethics. Consent to participate: This manuscript was presented by all the authors with honesty and without fabrication, falsification or inappropriate data manipulation. Consent for publication: All the authors have conformed to the manuscript and have agreed to its submissions for publication. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The impact of N,1-dibenzyl-5-methyl-1H-pyrazol-3-carboxamide (BPC) on the carbon steel (CS) corrosion in hydrochloric acid (1 M) was studied in this work, considering concentration and temperature effects. Electrochemical investigation indicated that BPC functions as a mixed-type inhibitor. For an optimal BPC concentration of 125 ppm, the inhibition efficiency of 91.55% was obtained at 298 K. According to adsorption isotherm of Langmuir, the BPC adheres to the CS with standard adsorption free energy (ΔG° ads ) of - 26.76 kJ mol -1 . Furthermore, the calculation of dissolution activation parameters revealed an increase in energy (E a ) from 46.48 to 94.97 kJ mol -1 , an elevation in the enthalpy (∆H a ) from 43.89 to 92.37 kJ mol -1 , and a rise in the entropy (∆S a ) from - 91.17 to 51.43 J mol -1  K -1 in the presence of 125 ppm of BPC. The experimental results were confirmed by quantum chemistry calculations based on density functional theory (DFT) and molecular simulations using the Monte Carlo method. These theoretical approaches also allowed for a comparison of the inhibitory performances of BPC with its protonated form, BPCH, the latter being found more effective. Moreover, the study of the radial distribution function g(r) predicted that the nature of the bond formed with the steel surface is of a chemical type., Competing Interests: Declarations. Ethics approval: The authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest or non-financial interest in the subject matter or materials discussed in this manuscript. Consent to participate: Not applicable for this research article. Consent for publication: Not applicable for this research article. Conflict of interest: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Graphene-based adsorbent was prepared by adopting a green synthetic route via the chemical exfoliation of graphite and low-temperature thermal activation. Prepared reactive graphene (RG) was characterized through various techniques, and its adsorption capabilities for textile dye removal were investigated for Acid Blue-93 (AB) and Reactive Red-195 (RR) under different operational conditions. The dye sorption equilibrium and mechanism were comprehensively studied using isotherm and kinetic models and compared statistically to explain the sorption behavior. Results show AB and RR adsorption by RG attains equilibrium in 60 min and 70 min, with a high sorption quantity of 397 mg g -1 and 262 mg g -1 (initial dye concentration of 100 mg L -1 ), respectively. The dye sorption anticipates that the high surface area (104.52 m 2 gm -1 ) and constructed meso-macroporous features of RG facilitated the interaction between the dye molecules and graphitic skeleton. The R-P isotherm fitted the best of equilibrium data, having the least variance in residuals for both dyes (AB = 0.00031 and RR = 0.00047). The pseudo-second order model best fitted the kinetics of sorption on RG, with chemisorption being the predominant process delimiting step. The overall results promise the dye removal capability of RG to be an efficient adsorbent for azo-based dyes from textile effluents., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Funtumia elastica husk was employed as an efficient and economically viable adsorbent to supplement traditional treatment methods in the removal of sulfamethoxazole from wastewater by converting it into usable material. The purpose of this study was to make biochar (FHB) from Funtumia elastica husk through the pyrolysis process and further modify the biochar using zinc oxide nanoparticles (ZnONPs) to a nanocomposite (FBZC). The antioxidant and antimicrobial characteristics as well as the potential of FBZC and FHB to sequester sulfamethoxazole from wastewater were investigated. Uptake capacities of 59.34 mg g -1 and 26.18 mg g -1 were attained for the monolayer adsorption of SMX onto FBZC and FHB, respectively. SEM and FTIR spectroscopic techniques were used to determine the surface morphology and chemical moieties of adsorbents, respectively. Brunauer-Emmett-teller (BET) surface analysis was used to assess the specific surface area of FHB (0.5643 m 2  g -1 ) and FBZC (1.2267 m 2  g -1 ). The Elovich and pseudo-first-order models are both well-fitted by the experimental data for FHB and FBZC, according to kinetic results. Nonetheless, the equilibrium data for FHB and FBZC were better explained by the Freundlich and Langmuir isotherm models, respectively. The pH PZC values of 6.83 and 5.57 were determined for FBZC and FHB respectively. Optimum solution pH, dosage, and contact time of 6, 0.05 g, and 120 min were estimated for FHB and FBZC. In conclusion, these findings demonstrate the strong potential of FBZC to simultaneously arrest the spread of pathogenic microbes and sequester sulfamethoxazole from wastewater., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: Not applicable. Consent for publication: All authors have studied the manuscript thoroughly and consented to the publication. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

The present study involved the preparation of a nano-polymer based on shrimp wastes as a biodegradable chitosan nanoparticle (Cs) incorporated into titanium oxide nanoparticles (TiO 2 ) in an aqueous medium and carried on the specific polymer to form thin films. The spectroscopic properties of chitosan/TiO 2 /Polymer thin films were estimated by transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy. The fabricated films were then examined for their potential to eliminate iron (Fe) and chromium (Cr) from solutions. The adsorption efficiency was also evaluated along various contact times. In general, the results illustrated that the heavy metals removal increases with increasing the different ratios of chitosan and TiO 2 nanoparticles incorporated in polymer thin films. Removal efficiency increased with an increase in contact time. More than 70% of Fe and Cr ions were removed in the first 30 min of contact time using different thin films examined. The maximum removal for metal ions after 90 min for the pest thin film (0.08 TiO 2 ) was 97.1 and 88.8% for Fe and Cr, whereas the lowest thin film removal efficiency (PVC) was 29.5 and 8.07% for Fe and Cr, respectively. In conclusion, the fabricated thin film composed of polyvinylidene chloride and chitosan plus 0.08 g titanium oxide nanoparticles had a heavy metal removal capacity three times greater than that of basic polyvinylidene chloride., Competing Interests: Declarations. Ethics approval: Not applicable. Consent to participate: All authors were involved in the experiments and writing process. Consent for publication: All authors of this article agreed to be published. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Herein, we demonstrate the preparation and application of NiCo 2 O 4 decorated over a g-C 3 N 4 -based novel nanocomposite (NiCo 2 O 4 @g-C 3 N 4 ). The prepared material was well characterized through several physicochemical techniques, including FT-IR, XRD, SEM, and TEM. The electrochemical characterizations via electrochemical impedance spectroscopy show the low electron transfer resistance of NiCo 2 O 4 @g-C 3 N 4 owing to the successful incorporation of NiCo 2 O 4 nanoparticles on the sheets of g-C 3 N 4 . NiCo 2 O 4 @g-C 3 N 4 nanocomposite was employed in the fabrication of a screen-printed carbon electrode-based innovative electrochemical sensing platform and the adsorptive removal of a food dye, i.e., fast green FCF dye (FGD). The electrochemical oxidation of FGD at the developed NiCo 2 O 4 @g-C 3 N 4 nanocomposite modified screen-printed carbon electrode (NiCo 2 O 4 @g-C 3 N 4 /SPCE) was observed at an oxidation potential of 0.65 V. A wide dual calibration range for electrochemical determination of FGD was successfully established at the prepared sensing platform, showing an excellent LOD of 0.13 µM and sensitivity of 0.6912 µA.µM -1 .cm -2 through differential pulse voltammetry. Further, adsorbent dose, pH, contact time, and temperature were optimized to study the adsorption phenomena. The adsorption thermodynamics, isotherm, and kinetics were also investigated for efficient removal of FGD at NiCo 2 O 4 @g-C 3 N 4 -based adsorbents. The adsorption phenomenon of FGD on NiCo 2 O 4 @g-C 3 N 4 was best fitted (R 2  = 0.99) with the Langmuir and Henry model, and the corresponding value of Langmuir adsorption efficiency (q m ) was 3.72 mg/g for the removal of FGD. The reaction kinetics for adsorption phenomenon were observed to be pseudo-second order. The sensitive analysis of FGD in a real sample was also studied., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: “The authors have no relevant financial or non-financial interests to disclose.”, (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Thin film of sensing unit, 2,3,9,10,16,17-hexakis(3-dietylaminophenoxy)-23-etynylphenyl-(2-ferrocenyl-o-carborane)phthalocyaninato zinc(II) (ZnPc), have been deposited by spray pyrolysis technique on the quartz crystal surface with a fundamental resonance frequency of 10 MHz. The surface morphology of the film has been studied using the contact mode atomic force microscope (AFM) technique and the average surface roughness was determined to be 36.4 nm. Then, this film was exposed to the vapors of methanol, ethanol, 2-propanol, and 1-butanol with various concentrations varying between 50 and 400 ppm. In addition, studies on response time and repeatability of the sensors have also been carried out. Films exhibit maximum sensing response to methanol vapor while the lowest sensitivity of the film towards 1-butanol has been observed. After an exposure time of 10 min, the frequency shift of 415 Hz was recorded for 400 ppm methanol vapor concentration, while a frequency shift of 215 Hz was observed for the same concentration of 1-butanol. The sensor was 1.30 times more sensitive to methanol vapor than ethanol and 2.00 times more sensitive to methanol than to 1-butanol. Variations in the sensitivity of the sensor have been correlated with the number of carbon groups in analyte vapors. The effect of the number of carbon groups in analyte molecule on adsorption kinetics of the film has also been investigated and compared. Adsorption isotherms of four volatile organic compounds on ZnPc were investigated at room temperature and the experimental data obtained were correlated with different existing adsorption isotherm models such as the Langmuir, the Freundlich, and Temkin model. An overall evaluation of the obtained results showed that the sensing performance, adsorption kinetic, and adsorption isotherms are dependent on the molecular size of the analyte molecules., Competing Interests: Declarations. Ethics approval and consent to participate: We certify that the manuscript titled “Adsorption of VOC Vapors on ZnPc: Sensing and Kinetic studies” has been entirely our original work, and it does not infringe the copyright of any third party. The submission of the manuscript to Environmental Science and Pollution Research implies that the work has not been published previously and is not under consideration for publication elsewhere; its publication is approved by all authors, and if accepted, the manuscript shall not be published elsewhere in the same form, in English or any other language, without the written consent of the publisher. Consent for publication: We affirm that all authors have agreed for the submission of the paper to ESPR and are fully aware of their ethical responsibilities. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

A major challenge that humans facing is the uncontrolled discharge of antibiotic-containing wastewater into the environment, accompanying with huge threats to human community. The utilization of cost-effective biomass-based adsorbents is considered a potential solution for the treatment of antibiotic wastewater. This study aims to optimize the synthesis of MgFe 2 O 4 nanoparticles loaded on prickly pear biochar (PPB) with outstanding sulfadiazine adsorbability using response surface methodology. Thirteen materials (MgFe 2 O 4 -PPB) produced based on Box-Behnken design were tested to evaluate the impact of the main factors on the material preparation process, including ratio of MgFe 2 O 4 :PPB precursors, calcination temperature and calcination time. Under optimized conditions, i.e., MgFe 2 O 4 :PPB ratio 0.5, temperature 600 °C and time 1 h, the production yield of 46.5% and sulfadiazine removal percentage of 85.4% were obtained. Characterization of optimized MgFe 2 O 4 -PPB indicated the good porosity and functionality suitable for the adsorption of sulfadiazine. Elovich model showed the best description of kinetic process. Temkin model was considered to be an accurate description of the isotherm adsorption. Proposed mechanism for antibiotic adsorption onto MgFe 2 O 4 -PPB was described. We clarify cost-benefit analysis to asses the importance of MgFe 2 O 4 -PPB as well as the economic and environmental impacts of biochar-based composites., Competing Interests: Declarations: The authors declare that • The manuscript has not been published anywhere nor submitted to another journal. • The manuscript is not currently being considered for publication in any another journal. • All authors have been personally and actively involved in substantive work leading to the manuscript, and will hold themselves jointly and individually responsible for its content. • Research does not involve any Human Participants and/or Animals. Ethics approval: Not applicable. Consent to participate: Not applicable. Consent for publication: Not applicable. Conflicts of interest/Competing interests: The authors declare that there are no conflicts of interest., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The progress of industrial and agricultural pursuits, along with the release of inadequately treated effluents especially phenolic pollutant, has amplified the pollution load on environment. These organic compounds pose considerable challenges in both drinking water and wastewater systems, given their toxicity, demanding high oxygen and limited biodegradability. Thus, developing an eco-friendly, low-cost and highly efficient adsorbent to treat the organic pollutants has become an important task. The present investigation highlights development of a novel adsorbent (CFPAC) by activation of Cassia fistula pod shell for the purpose of removing phenol and 2,4-dichlorophnenol (2,4-DCP). The significant operational factors (dosage, pH, concentration, temperature, speed) were also investigated. The factors such as pH = 2 and T = 20°C were found to be significant at 1.6 g/L and 0.6 g/L dosage for phenol and 2,4-DCP respectively. Batch experiments were further conducted to study isotherms, kinetic and thermodynamics studies for the removal of phenol and 2,4-DCP. The activated carbon was characterised as mesoporous (specific surface area 1146 m 2 /g, pore volume = 0.8628 cc/g), amorphous and pH PZC = 6.4. At optimum conditions, the maximum sorption capacity for phenol and 2,4-DCP were 183.79 mg/g and 374.4 mg/g respectively. The adsorption isotherm was better conformed to Redlich Peterson isotherm (phenol) and Langmuir isotherm (2,4-DCP). The kinetic study obeyed pseudo-second-order type behaviour for both the pollutants with R 2  > 0.999. The thermodynamic studies and the value of isosteric heat of adsorption for both the pollutants suggested that the adsorption reaction was dominated by physical adsorption (ΔH x  < 80 kJ/mol). Further, the whole process was feasible, exothermic and spontaneous in nature. The overall studies suggested that the activated carbon synthesised from Cassia fistula pods can be a promising adsorbent for phenolic compounds., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: Not applicable. Consent to publish: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

High-performing zeolite materials for carbon dioxide capture are promising for applications such as flue gas CO 2 capture. Potassium carbonate-loaded zeolites can offer a plethora of benefits. In this work, for the first time, zeolite-Y impregnated with K 2 CO 3 was studied as a gas adsorbent (CO 2 , CH 4 , and N 2 ) and characterized using TGA (thermogravimetric analyzer), XRD, BET, FTIR, FETEM (Field-Emission Transmission Electron Microscope), and XPS. The effect of carbonate loading, temperature, and pressure was particularly targeted and assessed. Accordingly, for a variation in K 2 CO 3 loading from 5 to 15 wt.%, the CO 2 adsorption capacity reduced from 3.61 to 1.73 mmol g -1 in the synthesized adsorbents. Among all the cases, KYZC10 exhibited very good cyclic adsorption-desorption performance and thermal stability. Further equilibrium modeling studies indicate that the stable and optimally K 2 CO 3 -loaded adsorbent (KYZC10) demonstrates effective adsorption isotherm behavior, making it suitable for different temperature variation processes in commercial carbon dioxide capture applications. The KYZC10 adsorbent's stable performance at varying temperatures contributes to its enhanced economic feasibility. This study also used the ideal adsorbed solution theory (IAST) to predict CO 2 selectivity over other gases (CH 4 and N 2 )., Competing Interests: Declarations. Ethical approval: We declare that all authors fully comply with ethical standards. Consent to participate: All participants in this study consented to participate in the research. Consent for publication: The manuscript has not been submitted nor is under consideration for publication by another journal and none of its contents have been previously published. All authors approved the final version for submission to your journal. All authors agreed to publish in the Journal of Environmental Science and Pollution Research. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Water contamination becomes one of the most high-priority environmental concerns, calling for the efficient treatment techniques. Bionanocomposites can be robust adsorbents, but the synthesis requires toxic chemicals or energy consuming and cause the secondary pollution. Green nanocomposites can be biogenically synthesized using the plant extract to end up with a critically safe strategy. Herein, we used the flower extract of Combretum indicum plant as a bio-based reductant and carbonaceous source for the green CuO@C nanocomposite. This green nanoadsorbent obtained a specific surface area of 17.33 m 2 /g, good crystallinity, and functional group-containing surface, i.e., -OH and -CONH-. We also conducted the optimization of parameters, i.e., concentration, CuO@C dose, pH, time, and temperature, and reached removal efficiencies towards malachite green (MG, 83.23%), Congo red (CR, 84.60%), brilliant blue (BB, 71.39%), and methylene blue (MB, 23.67%). The maximum adsorption capacities were found as ordered, MG (46.387 mg/g) > MB (23.154 mg/g) > BB (22.8 mg/g) > CR dye (11.063 mg/g). Through the intra-particle diffusion kinetic model, MG and BB adsorption endured a three-step process, while CR and MB adsorption was a two-step process. The recyclability of the green CuO@C nanocomposite was three cycles with 67.54% for the final cycle of BB removal. Moreover, the nanoadsorbent displayed a high stability, checked by X-ray diffraction, FT-IR analysis, EDX spectra, and SEM images. It is recommended that the green CuO@C nanocomposite biosynthesized using the Combretum indicum flower extract can be a good alternative for the dye treatment from wastewater., Competing Interests: Declarations. Ethical approval: Research does not involve any human participants and/or animals. Consent to participate: Not applicable. Consent for publication: The manuscript has not been published anywhere or submitted to another journal. The manuscript is not currently being considered for publication in any another journal. Competing interests: The authors declare no competing interests. Disclaimer: All authors have been personally and actively involved in substantive work leading to the manuscript, and will hold themselves jointly and individually responsible for its content., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)