This research evaluates the effectiveness of expired moldamin, a pharmaceutical waste material, as a corrosion inhibitorforAISI1010 steel exposed to aqueous solutions of1 M hydrochloric acid (HCl) and 1 M sulfuric acid (H2SO4) at 25 +/- 2 degrees C. The study utilized electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (Tafel analysis) to assess corrosion behavior. Adsorption properties were investigated using the Langmuir adsorption isotherm, and thermodynamic activation parameters were analyzed to determine the spontaneity of the adsorption process. Results indicate that moldamin acts as a mixed-type inhibitor, providing notable protection through both anodic and cathodic mechanisms, with particularly strong performance in sulfuric acid. The highest inhibition efficiencies observed were 89.23% in HCl and 88.7% in H(2)SO(4 )at a concentration of 10(-3) M. Surface characterization using 3D laser microscopy confirmed a marked decrease in surface roughness. Overall, the findings highlight moldamin's potential for both corrosion control and sustainable management of pharmaceutical waste.

Peels of vegetable waste (VW), rich in cellulose, lignin, and hemicellulose, can impede hydrolysis due to reduced enzymatic accessibility and activity. This research comparatively evaluated the effects of composite vegetable waste (CVW) comprising of 2:3 food waste (FW):VW on biological buffering potential and enzymatic activity during acidogenesis in a two-stage (Leached Bed Reactor-airlift reactor) system. Results demonstrated that maximum buffering and enzymatic activity occurred within the first 3-5 days. The system maintained an in situ maximum buffering capacity of 0.145 mol/L (FW) and 0.089 mol/L (CVW) without chemical additives. Peak α-amylase activities reached 72.2 U/mL (FW) and 64 U/mL (CVW), while protease reached 34.94 U/mL (CVW). The ratio of 2:3 for FW:VW moderated enzymatic hydrolysis rates through its lignocellulosic content and stabilized the acidogenic environment, which in turn regulated VFA dynamics, resulting in a 1.8-fold increase in acetate yield (18.19 g/L). Conversely, FW achieved a higher biohydrogen yield of 121.3 mL/g VS (43% composition) compared to 110 mL/g VS (36.4% composition) for CVW. The FW also produced 4.2 times higher propionic acid (95.3 g/L) than CVW (22.64 g/L). Life Cycle Assessment (LCA) confirmed the sustainability of this minimized-discharge model, with H2 production from FW showing a lower Global Warming Potential (0.056 kg CO2 eq/L) than CVW (0.269 kg CO2 eq/L) due to higher gas yields. The system maintained in situ buffering without chemical additives, thus advancing the development of cost-effective routes for bioresource recovery from complex organic waste. It has also been emphasized that the sustainability of process is bolstered by the recirculation of airlift reactor effluent, which mitigates the need for chemical additives.

Regulation of in situ hydrogen partial pressure enhances hydrolysis efficiency and reduces hydraulic retention time during the acidogenic phase of kitchen waste digestion. High-solids anaerobic digestion systems (>20% total solids) require a comprehensive understanding of acidogenic microorganisms that can withstand dynamic headspace pressures and varying substrate compositions. This research explores a two-stage digestion process incorporating an enriched inoculum with pressure-assisted hydrolysis in a leach bed reactor (LBR) linked to an up-flow anaerobic sludge blanket (UASB) reactor to optimize energy recovery from kitchen waste (KW). The KW was mixed with the enriched inoculum and digested in LBRs under controlled headspace pressures of 3 psi (20.7 kPa) and 12 psi (82.7 kPa), using pre-mixed biogas (CH4:CO2 = 60:40). The system operated at 12 psi exhibited elevated levels of soluble chemical oxygen demand (sCOD: 559.2 g/kg VS) and total soluble products (TSP: 362 g/kg VS) compared to the 3 psi condition (sCOD: 425.1 g/kg VS; TSP: 294 g/kg VS). Microbial community analysis revealed pressure-driven shifts favouring Pseudomonas, Escherichia, and Clostridium species. Metabolite profiling indicated butyrate dominance at 12 psi, while propionate concentrations were higher at 3 psi. Methane yield in the UASB reactor paired with the 12 psi LBR (421.8 L/kg VS) was higher relative to the 3-psi setup (310.1 L/kg VS). These findings underscore the effectiveness of combining tailored microbial consortia with pressure and gas composition control to enhance intermediate metabolite conversion and overall bioenergy output in high-solids anaerobic digestion systems.

This review addresses the escalating global water crisis driven by water pollution, especially by heavy metal ions, a consequence of rapid industrialization and population growth. Due to their high toxicity, solubility, and persistence, heavy metals pose a severe threat to human health and ecosystems through bioaccumulation. The analysis highlights a strategic shift in wastewater management from simple elimination of the toxics metal ions to the recovery of metal ions with economic value. Given the increasing complexity of industrial effluents, the scientific community is intensifying its focus on evaluating the technical and financial feasibility of various treatment technologies. Significant research is being conducted to address these environmental issues, and innovative technologies are being developed to enhance the quality of water contaminated by metal ions. On the other hand, to prevent pollution, plans containing several barriers must be established, including management, economic, and technical ones. Ultimately, the reuse of treated wastewater is the only viable long-term solution for securing global drinking water supplies. A new analysis focused on the transition from traditional, inefficient, and costly wastewater treatment to advanced, resource recovery-oriented systems is essential. The current perspective shows a clear need to advance beyond synthetic laboratory studies to real-world applications while addressing operational barriers to support a circular economy based on simple disposal of the toxic metal ions to the recovery of metals with economic value (e.g., copper, gold, silver, rare metals). Also, although the field has been explored, a new review is imperative because current technologies that show high efficiency (up to 99%) in the removal of toxic metal ions (adsorption, membrane filtration, electrochemical processes) face major challenges, such as the formation of large volumes of toxic sludge, membrane fouling, and high operating costs.

A flexible, lightweight and low-cost enzymatic bioanode was developed using a screen-printed silver conductive transparency sheet for enzymatic biofuel cell (EBFC) applications. In this work, indole was electrochemically polymerized directly onto the conductive substrate to form a polyindole (PIn) matrix capable of simultaneously entrapping glucose oxidase (GOx) and redox mediator vitamin K3 (VK3). The study integrates a disposable transparency-sheet platform with an electroactive PIn network that promotes efficient enzyme immobilization and enhanced electron transfer for glucose bioelectrocatalysis. The synergistic interaction between PIn, VK3 and GOx significantly improved charge-transfer kinetics and stabilized the bioelectrocatalytic interface, resulting in enhanced electrochemical performance. The fabricated PIn/VK3/GOx bioanode exhibited a current density of 1.18 mA cm- 2 in 40 mM glucose solution, demonstrating efficient glucose-dependent electrocatalytic activity. The conductive PIn framework facilitated rapid electron transport between the buried active sites of GOx and the electrode surface, while VK3 acted as an efficient and biocompatible electron shuttle. The bioanode also displayed good electrical stability, semiconducting behavior, and favorable electrochemical characteristics, highlighting its suitability for flexible and wearable bioelectronic applications.

Background: Aristolochia clematitis L. (AC), a plant with diverse traditional uses, has gained increasing scientific interest due to its rich content of bioactive compounds such as flavonoids and polyphenols. However, its systemic use is limited by the presence of aristolochic acids, which are known for their nephrotoxic and carcinogenic potential. Methods: In this context, the present study investigates the therapeutic potential of A. clematitis extract by encapsulating it in liposomes with the aim of enhancing its topical efficacy. Results: The extract was characterized in terms of its flavonoid content (67.23 ± 0.33 mg QE/g DW (quercetin/dry plant material)) and polyphenols expressed as gallic acid equivalents (64.38 ± 0.16 mg GAE/g DW), as well as its antioxidant capacity using the reagents 1,1-diphenyl-2-picrylhydrazyl (DPPH − IC50 = 0.1619 mg/mL extract) and diammonium 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS − IC50 = 205.57 μg/mL extract). Four types of liposomes were synthesized (two loaded with extract and two empty), and their characterization was performed using Atomic Force Microscopy (AFM), Dynamic Light Scattering (DLS), Zeta Potential, polydispersity index, and in vitro release studies. Conclusions: The results demonstrated a high entrapment efficiency (over 82%), good stability over 30 days, and controlled release of flavonoids. Microbiological studies revealed relevant antimicrobial activity against Staphylococcus aureus, Streptococcus pneumoniae, Escherichia coli, and Pseudomonas aeruginosa strains. The evaluation on HaCaT skin-derived cells (at 10–100 µg/mL) proved that the samples displayed good overall tolerability, slightly decreasing cell viability (the most statistically significant being associated with AC treatment) and showing no structural, nuclear, or mitochondrial morphological changes.

The purpose of this study was to examine the utilization of 0-45 mu m aluminum hydrate fraction (gibbsite) manufactured by Alum SA Tulcea, as a precursor in the hydrothermal synthesis process of nanosize boehmite from gibbsite suspensions. Furthermore, the use of the produced material as adsorbent of lanthanum (III) ions was investigated using aqueous solutions. Thermogravimetric analysis (TG), Fourier Transform InfraRed Spectroscopy (FT-IR), Wide-Angle X-Ray Scattering (WAXS), and atomic force microscopy (AFM) were used to demonstrate the preparation of the required material. Additionally, the material point of zero charge (pHpzc) and material specific surface (using BET approach) were evaluated. By conducting adsorption studies, the specific parameters for the lanthanum adsorption process were evaluated. The effects of pH, the ratio of adsorbent material to La(III) quantity from aqueous solution, contact time, and La(III) initial concentration were also assessed. Based on the obtained experimental data, it was proved that the maximum adsorption capacity of 97.7 mg/g was obtained for a solid:liquid ratio = 0.1 g:25 mL, pH between 3 and 6, temperature of 298 K, and contact time of 90 min. The studied adsorption process is most effectively described by the Sips model, suggesting an intricate interaction among the adsorbent material and La (III) ions. The prepared adsorbent exhibited a good desorption capacity (higher than 93%) when 20% HCl was used for desorption.

In the present study three composite materials based on iron in combination with bismuth, copper or lithium carbonates FeNO3@Li2CO3 (SFL), FeNO3@CuCO3 (SFC), and FeNO3@(BiO)2CO3 (SFB) were synthesized by coprecipitation. The purpose was to obtain materials that possess targeted adsorbent properties for the recovery of silver ions from aqueous solutions. After synthesis, to emphasize the adsorptive qualities of materials for the recovery of silver ions, the synthesized composite materials, as well as those doped with silver ions following the adsorption process (SFL-Ag, SFC-Ag, and SFB-Ag), were characterized and several adsorption-specific parameters were examined, including temperature, contact time, pH, adsorbent dose, and the initial concentration of silver ions in solution. Subsequently, the ideal adsorption conditions were determined to be as follows: pH > 4, contact time 60 min, temperature 298 K, and solid–liquid ratio (S–L) of 0.1 g of adsorbent to 25 mL of Ag (I) solution for all three materials. The Langmuir model properly fits the experimental equilibrium data of the adsorption process; however, the Ho–McKay model closely represents the adsorption kinetics. The maximum adsorption capacities of the materials, 19.7 mg Ag(I)/g for SFC, 19.3 mg Ag(I)/g for SFB, and 19.9 mg Ag(I)/g for SFL, are comparable. The adsorption mechanism is physical in nature, as evidenced by the activation energies of 1.6 kJ/mol for SFC, 4.15 kJ/mol for SFB, and 1.32 kJ/mol for SFL. The highest Ag(I) concentration used for doping all three materials in the study was 150 mg Ag(I)/L. The process is endothermic, spontaneous, and takes place at the interface between the adsorbent and the adsorbate, according to thermodynamic theory. Subsequently, the antimicrobial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans microorganisms was evaluated by rate of inhibition assessment. The SFC-Ag material showed a percentage of 100% inhibition with respect to the positive control for each microorganism. All synthetized materials have better efficiency as antifungal agents.

Present study focuses on the evaluation of the energy storage performance of possible pyrophosphate super-capacitor materials obtained by dealloying process. The electrochemical behavior was investigated by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) techniques using a system based on three-electrode cell in 1 M KOH electrolyte solution. A direct assessment of the influence of dealloying time for capacitance was performed, showing that partial dealloying improves energy storage. Furthermore, the synthesized materials were investigated morpho-structurally to present behavior of the materials at immersion times between 3 and 24 h. Obtained results presents that the highest capacitance value about 269.36 mF cm-2 measured from CV analysis was observed for the electrode at 3 h immersion time at 5 mV s-1 scan rate. The GCD results confirmed also the superiority of the electrode material by recording the maximum specific capacitance of 268.7 mF cm-2 at 1 mA cm-2 calculated for the electrode at 3 h immersion time. All the as-synthesized electrodes presented an excellent cyclic stability showing an increase in retention rates over 100 %. For the as-obtained electrode a retention rate about 129.33 % at 24 h immersion time over 500 cycles, was obtained. In addition, aqueous symmetric supercapacitors were assembled based on the experimental program. Capacitance values were calculated from the CV data as a function of potential window and scan rate. The highest capacitance was observed for the CSP-12 h//CSP-12 h symmetric supercapacitor, reaching 49.24 mF cm-2 at 1.4 V. As a function of scan rate, the CSP-24 h//CSP-24 h device exhibited the highest capacitance, reaching 45.72 mF cm-2 at 5 mV s-1. GCD measurements as a function of potential window showed that the CSP-6 h//CSP-6 hand CSP-12 h//CSP-12 h devices demonstrated the best performance, with the highest capacitance values of approximately 46 mF cm-2 achieved at 1.4 V. Furthermore, the CSP-12 h//CSP-12 h device delivered a power density of 5.46 mW cm-2 at an energy density of 0.027 mWh cm-2. Over 3000 cycles, the maximum retention rate was approximately 30.42 %, observed for the CSP-3 h//CSP-3 h device. This research presents a promising technique for producing pyrophosphate material for supercapacitor application.

The European Union regards gallium as a crucial element. Because of that, the retrieval of gallium ions from secondary sources through diverse methodologies is of the utmost significance in an actual economical context. The primary goal of this study was to explore the viability of MgFe2O4 spinel as an adsorbent material for Ga(III) ions recovery from aqueous solutions. A spinel adsorbent material was synthesised by using the sol–gel synthesis method. After preparation, the obtained spinel was subjected to a thermal treatment, which resulted in modifications of its crystalline structure and morphology, in concordance with the calcination temperatures. Specifically, two distinct temperatures of 260 and 650 °C were utilised in the process, which was conducted in air. The second objective was represented by the physicochemical characterisation of the newly prepared adsorbent material by using various analytical techniques, e.g., Fourier transform infrared spectroscopy (FT-IR), atomic force microscopy (AFM) and magnetic measurements. The optimal conditions for Ga(III) adsorption were established (S:L ratio, solution pH, contact time, temperature, initial Ga(III) concentration). Simultaneously, the obtained experimental data were modelled to prove the fact that the pseudo-second-order model explained the studied kinetics process and established its mechanism. Intraparticle diffusion was also studied to highlight the rate-determined step during the Ga(III) adsorption process. The equilibrium of the process was also studied, establishing that the Sips isotherm fitted the experimental data best, with a correlation coefficient R2~1, indicating that the studied adsorption process was homogeneous, the maximum adsorption capacity of spinel being 24.7 mg Ga (III)/g MgFe2O4. Thermodynamic parameters, involving ΔG°, ΔH° and ΔS°, were also calculated; negative values of ΔG° indicated that the adsorption was spontaneous. ΔH° proved to be endothermic, and the calculated ΔS° values being positive confirmed the fact that the process was spontaneous.

The need to develop advanced wastewater treatment techniques and their use has become a priority, the main goal being the efficient removal of pollutants, especially those of organic origin. This study presents the photo-degradation of a pharmaceutical wastewater containing Kabi cytarabine, using ultraviolet (UV) radiation, and a synthesized catalyst, a composite based on bismuth and iron oxides (BFO). The size of the bandgap was determined by UV spectroscopy, having a value of 2.27 eV. The specific surface was determined using the BET method, having a value of 0.7 m2 g−1. The material studied for the photo-degradation of cytarabine presents a remarkable photo-degradation efficiency of 97.9% for an initial concentration 0f 10 mg/L cytarabine Kabi when 0.15 g of material was used, during 120 min of interaction with UV radiation at 3 cm from the irradiation source. The material withstands five photo-degradation cycles with good results. At the same time, through this study, it was possible to establish that pyrimidine derivatives could be able to combat infections caused by Escherichia coli and Candida parapsilosis.

Given the ever-increasing demand for gallium(III) as a crucial precursor in the fabrication of advanced materials, there arises an imperative to devise efficient recovery processes from primary and secondary sources. In the present investigation, the retrieval of gallium(III) from aqueous solutions through the mechanism of adsorption was investigated. Materials with superior adsorbent properties play an important role in the dynamics of the adsorption process. To enhance these properties, select materials, such as Amberlite-type polymeric resins, are amenable to functionalization through impregnation with extractants featuring specialized active groups, designed for the selective recovery of metal ions—specifically, Ga(III). The impregnation method employed in this study is the Solvent-Impregnated Resin (SIR) method, utilizing the amino acid DL-valine as the extractant. The new material was characterized through Scanning Electron Microscopy (SEM), Elemental Analysis via X-ray energy-dispersive spectroscopy (EDX), and Fourier transform infrared spectroscopy (FTIR) to elucidate the presence of the extractant on the resin’s surface. Concurrently, the material’s pHPZC was determined. The adsorptive prowess of the synthesized material was investigated through kinetic, thermodynamic, and equilibrium studies. The influence of specific parameters in the adsorption process—namely, pH, contact time, temperature, and Ga(III) initial concentration—on the maximal adsorption capacity was determined. The optimal adsorption conditions were established using the Taguchi method.

The aim of this study was to develop new materials with adsorbent properties that can be used for the adsorption recovery of Au(III) from aqueous solutions. To achieve this result, it is necessary to obtain inexpensive adsorbent materials in a granular form. Concomitantly, these materials must have a high adsorption capacity and selectivity. Other desired properties of these materials include a higher physical resistance, insolubility in water, and materials that can be regenerated or reused. Among the methods applied for the separation, purification, and preconcentration of platinum-group metal ions, adsorption is recognised as one of the most promising methods because of its simplicity, high efficiency, and wide availability. The studies were carried out using three supports: cellulose (CE), chitosan (Chi), and diatomea earth (Diat). These supports were functionalised by impregnation with extractants, using the ultrasound method. The extractants are environmentally friendly and relatively cheap amino acids, which contain in their structure pendant groups with nitrogen and sulphur heteroatoms (aspartic acid—Asp, l-glutamic acid—Glu, valine—Val, DL-cysteine—Cys, or serine—Ser). After preliminary testing from 75 synthesised materials, CE-Cys was chosen for the further recovery of Au(III) ions from aqueous solutions. To highlight the morphology and the functionalisation of the material, we physicochemically characterised the obtained material. Therefore, the analysis of the specific surface and porosity showed that the CE-Cys material has a specific surface of 4.6 m2/g, with a porosity of about 3 nm. The FT-IR analysis showed the presence, at a wavelength of 3340 cm−1, of the specific NH bond vibration for cysteine. At the same time, pHpZc was determined to be 2.8. The kinetic, thermodynamic, and equilibrium studies showed that the pseudo-second-order kinetic model best describes the adsorption process of Au(III) ions on the CE-Cys material. A maximum adsorption capacity of 12.18 mg per gram of the adsorbent material was achieved. It was established that the CE-Cys material can be reused five times with a good recovery degree.

In an actual economic context, the demand for scandium has grown due to its applications in top technologies. However, further development of new technologies will lead to an increase in the market for Sc related to such technologies. The present study aims to improve and upgrade existing technology in terms of efficient scandium recovery, proposing a new material with selective adsorptive properties for scandium recovery. To highlight the impregnation of Amberlite XAD7HP resin with tri-n-octylphosphine oxide extractant by the solvent-impregnated resin method, the obtained adsorbent material was characterized by physico-chemical techniques. Further, the specific surface of the adsorbent and the zero-point charge of the adsorbent surface have been determined. Different parameters, such as initial concentration, adsorbent amount, contact time, or temperature, have been studied. The initial pH effect was investigated when a maximum adsorption capacity of 31.84 mg g−1 was obtained at pH > 3, using 0.1 g of adsorbent and a contact time of 90 min and 298 K. An attempt was made to discuss and provide a clear representation of the studied adsorption process, proposing a specific mechanism for Sc(III) recovery from aqueous solutions through kinetic, thermodynamic, and equilibrium studies. Adsorption/desorption studies reveal that the prepared adsorbent material can be reused five times.

This study focuses on the growth of Cu2O/CuO nanowires by one-step thermal oxidation using a flexible copper mesh at oxidation temperatures in the range of 300 to 600 °C in a controlled atmosphere of mixed-flow Ar and O2 gases. Thermal oxidation is one of the simplest used methods to obtain nanowires on a metal surface, offering advantages such as low production costs and the ability to produce metal oxides on a large scale without the use of hazardous chemical compounds. The growth of metal oxides on a conductive substrate, forming metal/oxide structures, has proven to be an effective method for enhancing charge-transfer efficiency. The as-synthesized Cu/Cu2O/CuO (Nw) electrodes were structurally and morphologically characterized using techniques such as XRD and SEM/EDX analysis to investigate the structure modification and morphologies of the materials. The supercapacitor properties of the as-developed Cu/Cu2O/CuO (Nw) electrodes were then examined using cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) measurements, and electrochemical impedance spectroscopy (EIS). The CV curves show that the Cu/Cu2O/CuO (Nw) structure acts as a positive electrode, and, at a scan rate of 5 mV s −1, the highest capacitance values reached 26.158 mF cm−2 for the electrode oxidized at a temperature of 300 °C. The assessment of the flexibility of the electrodes was performed at various bending angles, including 0°, 45°, 90°, 135°, and 180°. The GCD analysis revealed a maximum specific capacitance of 21.198 mF cm−2 at a low power density of 0.5 mA cm−2 for the oxidation temperature of 300 °C. The cycle life assessment of the all of the as-obtained Cu/Cu2O/CuO (Nw) electrodes over 500 cycles was performed by GCD analysis, which confirmed their electrochemical stability.

The main goal of this systematic review on the flavonol class secondary metabolite quercetin is to evaluate and summarize the existing research on quercetin’s potential health benefits, therapeutic properties, and effectiveness in disease prevention and treatment. In addition to evaluating quercetin’s potential for drug development with fewer side effects and lower toxicity, this type of review attempts to collect scientific evidence addressing quercetin’s roles as an antioxidant, anti-inflammatory, antibacterial, and anticancer agent. In the first part, we analyze various flavonoid compounds, focusing on their chemical structure, classification, and natural sources. We highlight their most recent biological activities as reported in the literature. Among these compounds, we pay special attention to quercetin, detailing its chemical structure, physicochemical properties, and process of biosynthesis in plants. We also present natural sources of quercetin and emphasize its health benefits, such as its antioxidant and anti-inflammatory effects. Additionally, we discuss methods to enhance its bioavailability, analyzing the latest and most effective delivery systems based on quercetin.

The objective of this study was to develop microspheres (Ms) from natural materials, chitosan (Ch) and sodium alginate (Na-Alg), that protect Ruta graveolens L. (RG) extract against temperature, pH, and the oxidative impact of degradation. The microspheres also masked the unpleasant taste by enclosing them in a biodegradable polymeric matrix. First, the total polyphenols, total flavonoid content, and antioxidant activity were quantified spectrophotometrically. Individual polyphenol contents were identified and quantified by high-performance liquid chromatography (HPLC) with UV detection. The RG extract was encapsulated in microspheres of chitosan–sodium alginate–Ruta graveolens L. extract (CARG-Ms) using two distinct procedures (method 1, in which the RG extract was added to the Ch solution and the Na-Alg solution was dripped into this mixture, and method 2, in which the RG extract was added to the Na-Alg solution and then dripped into the Ch solution) to determine which method was more advantageous. All microspheres were evaluated and characterized by confocal laser-scanning microscopy (CLSM), scanning electron microscopy (SEM), optical scanning, entrapping efficiency (EE%), swelling index (SWL%), and in vitro release (RGrel%), and all results underwent univariate and multivariate analysis using a regression model. Following these tests, it was observed that the extract had an appreciable flavonoid content of 37.98%, with antioxidant properties evidenced by the 54.25% inhibition of DPPH. Of the polyphenolic compounds identified in the extract by using the HPLC method, rutin was present in the highest amount, at 745.17 μg/mL. The microspheres prepared by method 2, which contained the highest concentration of chitosan, had several desirable properties, including a high degree of roughness, high entrapping efficiency (75%), a wrinkled appearance, a better in vitro release capacity, and a lower SWL%. On the other hand, CARG-Ms prepared by method 1, which contained a smaller concentration of Ch, had faster swelling and slower release of the extract due to the lower entrapping efficiency (35%). These results suggest that the concentration of wall material and the preparation method play important roles in the encapsulation process and final particle characteristics. According to the obtained results, after the multivariate statistical analysis, it can be observed that the microspheres prepared via method 2 of the complex coacervation process were the most efficient for encapsulating rue extract in microspheres, because the extract was protected against degradation from the gastrointestinal tract.

The remediation of arsenic contamination in potable water is an important and urgent concern, necessitating immediate attention. With this objective in mind, the present study investigated arsenic removal from water using batch adsorption and fixed-bed column techniques. The material employed in this study was a waste product derived from the treatment of groundwater water for potable purposes, having a substantial iron composition. The material’s properties were characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and Fourier-transformed infrared spectroscopy (FT-IR). The point of zero charge (pHPZC) was measured, and the pore size and specific surface area were determined using the BET method. Under static conditions, kinetic, thermodynamic, and equilibrium studies were carried out to explore the influencing factors on the adsorption process, namely the pH, contact time, temperature, and initial arsenic concentration in the solution. It was found that the adsorption process is spontaneous, endothermic, and of a physical nature. In the batch adsorption studies, the maximum removal percentage was 80.4% after 90 min, and in a dynamic regime in the fixed-bed column, the efficiency was 99.99% at a sludge:sand = 1:1 ratio for 380 min for a volume of water with arsenic of ~3000 mL. The kinetics of the adsorption process conformed to a pseudo-second-order model. In terms of the equilibrium studies, the Sips model yielded the most accurate representation of the data, revealing a maximum equilibrium capacity of 70.1 mg As(V)/g sludge. For the dynamic regime, the experimental data were fitted using the Bohart–Adams, Thomas, and Clark models, in order to establish the mechanism of the process. Additionally, desorption studies were conducted, serving as an essential step in validating the practical applicability of the adsorption process, specifically in relation to the reutilization of the adsorbent material.