Mageda Ali Akl

Finding new affordable biosorbents for the remediation of toxic inorganic pollutants is a great challenge. This challenge arises from the need for biosorbents with functional groups that can efficiently chelate heavy metals and facilitate their removal from water. The present study examines the application of the local Egyptian Sahara medicinal plant Anabasis articulata , in both raw (ANA) and NaOH-modified (ANAS) forms, as biosorbents for removing Pb(II) ions from aqueous solutions. The characterization of both biosorbents was conducted using multiple analytical techniques, such as Fourier-transform infrared spectroscopy (FT-IR), Brunauer–Emmett–Teller (BET) surface area analysis, Boehm titration, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The effects of experimental variables on Pb(II) biosorption, including initial Pb(II) concentration, pH, biosorbent dosage, contact duration, and the presence of foreign ions, were systematically investigated. To ensure the reliability of the kinetic and isotherm adsorption models, error functions, including χ ² , SSE, and MSE, were used as validation tools. Analysis of adsorption equilibrium data demonstrated that the Langmuir model most accurately described the process, yielding maximum capacities of 76.38 ± 0.26 mg/g and 46.74 ± 0.21 mg/g for ANA and ANAS, respectively. A measurable enhancement in adsorption was observed following mercerization, which altered the dominant Pb(II) binding mechanism. Thermodynamic analysis revealed that Pb(II) biosorption on ANA and ANAS was exothermic and endothermic, respectively. The ANA extract exhibited significant antioxidant activity as determined by the DPPH radical scavenging assay. Furthermore, the methanolic extract of ANA showed potential antimicrobial activity against both Gram-negative and Gram-positive bacteria. The mechanism of Pb(II) biosorption onto ANA and ANAS biosorbents is elucidated. The ANAS biosorbent, produced via a simple, environmentally friendly process, offers a sustainable solution for wastewater treatment in arid regions.

Efficient removal of organic pollutants from water remains a major challenge. In this work, a circular economy strategy is adopted to address critical challenges associated with excessive waste generation, resource limitations, and economic sustainability. Sugarcane bagasse (SCB), an abundant lignocellulosic agricultural waste, was utilized as a sustainable adsorbent for the sequential removal of oppositely charged dyes from aqueous solutions. Pristine SCB was first employed for the adsorption of the anionic dye Alizarin Red S (ARS), and the resulting spent adsorbent (SCB@ARS) was subsequently reused without regeneration for the removal of the cationic dyes Crystal Violet (CV) and Methyl Green (MG). The adsorbents were characterized using point of zero charge (pH _PZC ), Fourier-transform infrared spectroscopy (FTIR), Thermogravimetric analysis (TGA), Scanning electron microscopy (SEM), and Energy-dispersive X-ray spectroscopy (EDX). The effects of adsorption parameters, including shaking time, pH, dye concentration, and adsorbent dose, were studied. The maximum adsorption capacities of SCB for ARS and SCB@ARS for CV and MG were 99.38, 136.84, and 452.26 mg/g, respectively. Kinetic, isotherm, and thermodynamic studies indicated that the adsorption process was best described by the linear pseudo-2nd-order and nonlinear pseudo-1st-order kinetic models and the Langmuir isotherm model, and was thermodynamically feasible and spontaneous. The adsorption mechanism was further elucidated using pH _PZC and FTIR analyses. Recovery studies in pharmaceutical and real water samples demonstrated removal efficiencies exceeding 90%. A one-way ANOVA statistical analysis was used to evaluate the effect of pH on adsorption. These findings highlight the potential of sequential adsorption using renewable agricultural waste as an effective and sustainable wastewater treatment strategy.

In this work, a novel delafossite AgFeO ₂ -based pomegranate peel activated carbon nanocomposite (AgFeO ₂ /PPAC) was synthesized via a hydrothermal route. Structural and surface characterization (XRD, SEM–EDX, BET, TGA, and FTIR) of PPAC and AgFeO ₂ /PPAC nanocomposite indicate successful deposition of AgFeO ₂ onto a porous carbon matrix with high surface area. The AgFeO ₂ /PPAC nanocomposite was evaluated for the removal of the anionic Brilliant Blue R (BBR) and the cationic Neutral Red (NR) dyes from aqueous solutions under visible light. The AgFeO ₂ /PPAC nanocomposite shows high removal efficiency toward both dyes in single and binary systems. The experimental data fit well with the Langmuir isotherm model, suggesting monolayer adsorption under the studied conditions. The maximum adsorption capacities are 798.6 mg g ⁻¹ for NR and 598 mg g ⁻¹ for BBR. Kinetic analysis shows good agreement with the pseudo-second-order model (PSO), indicating that surface interactions contribute to the adsorption process. Thermodynamic parameters indicate a spontaneous and endothermic process. The overall removal performance is attributed to the combined contribution of adsorption and photocatalytic activity. The AgFeO ₂ /PPAC nanocomposite demonstrates stable performance over repeated cycles, indicating good reusability. These findings suggest that the developed material is a promising candidate for wastewater treatment applications .

Aqueous Zinc‐ion batteries (AZIBs) are receiving significant attention due to their high volumetric energy density, increased safety and lower cost compared to alternative energy storage systems. The use of Zinc metal as an anode, however, creates stability challenges due to dendrite formation as well as side reactions from surface imperfections. In this work, hierarchical surface modification to Zinc metal anodes via a low energy, scalable Argon plasma is introduced. This approach smooths surfaces and heals defects on a micron scale while simultaneously Zinc nanoisland seed layers are formed. Plasma induced surface reconstruction also leads to a significant reduction in surface impurities. Moreover, Zinc nanoisland seed layers are found to be beneficial for suppressing the dendrite formation through surface homogenization. Unlike unstable and short‐lived bare Zn metal anodes, plasma treated anodes exhibits enhanced rate performances and superior stability even after long‐term cycling demonstrated by symmetric cell test and full cell tests with both MnO ₂ and V ₂ O ₅ cathode tested under different electrolytes. These results demonstrate that plasma enabled surface modification of Zn metal anode is an effective strategy for improving the overall AZIB performance, especially the cycling stability in a facile manner, resolving one of the key challenges to commercializing AZIBs.

Efficient enrichment and remediation of heavy metals from real wastewater and contaminated soil, both of which frequently contain high concentrations of competing ions, remain significant challenges. Producing advanced carbon-based materials that efficiently remove contaminants from water is crucial for environmental remediation and public health. This investigation describes the concurrent activation and magnetization processes used to synthesize Mag@SAC, a magnetic sugarcane activated carbon, from carbonized sugarcane bagasse (SB) using Fe³⁺ and Fe²⁺ ions. The Mag@SAC biocomposite was thoroughly characterized using Brunauer–Emmett–Teller (BET) and N₂ adsorption isotherm analysis, point of zero charge (pH_PZC), elemental analysis, Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and Thermogravimetric analysis (TGA). The as-prepared Mag@SAC was applied to remove toxic heavy metals, Pb²⁺ and Hg²⁺ from solutions, with easy separation achieved by simply applying an external magnet. The adsorption of Pb²⁺ and Hg²⁺ onto Mag@SAC biocomposite follows pseudo-second-order (PSO) kinetics and is best described by the Langmuir isotherm, indicating spontaneous, monolayer chemisorption. This process is supported by a high correlation coefficient (R² ≥ 0.999) and low error functions. Maximum adsorption capacities of 90.82 mg g⁻¹ for Pb²⁺ and 164.20 mg g⁻¹ for Hg²⁺ were obtained under optimal conditions. Thermodynamic analysis indicates that the adsorption of Hg²⁺ onto Mag@SAC is spontaneous and endothermic, whereas the adsorption of Pb²⁺ is spontaneous and exothermic. The Mag@SAC biocomposite can be successfully regenerated up to the 5^th cycle. The mechanisms of adsorption of Pb²⁺ and Hg²⁺ onto the Mag@SAC were elucidated.

Ensuring safe and accessible drinking water requires effective wastewater treatment. In this work, pristine corn husk biosorbent (CH) was employed as a low-cost material for the removal of Basic Fuchsin (BF) and Crystal Violet (CV) dyes. The CH biosorbent was comprehensively characterized through elemental analysis, scanning electron microscopy (SEM), N₂ adsorption–desorption isotherms, Brunauer–Emmett–Teller (BET) surface area measurements, Fourier transform infrared spectroscopy (FTIR), point of zero charge (pH _PZC ), and thermogravimetric analysis (TGA). Batch adsorption studies were carried out to evaluate the influence of various operating parameters, such as CH biosorbent dosage, contact time, temperature, and initial dye concentration. The adsorption kinetics were found to fit the pseudo-second-order model, while the equilibrium isotherm data aligned best with the Langmuir model, showing high correlation coefficients (R² ≥ 0.999) and low error values compared to other tested models. The maximum adsorption capacities were determined to be 77.3 mg/g for BF and 88.8 mg/g for CV. Thermodynamic analysis indicated that the uptake of both dyes onto the CH biosorbent is spontaneous and endothermic. Response surface methodology (RSM) with a central composite design (CCD) was employed to fine-tune the reaction parameters and optimize the adsorption process. The adsorption mechanism is attributed to a combination of electrostatic attraction, π–π stacking, n–π interactions, hydrogen bonding, and pore diffusion. The CH biosorbent demonstrated good reusability, maintaining its performance through five regeneration cycles. Additionally, antibacterial activity tests of the CH biosorbent were conducted before and after dye uptake to assess potential toxicity. The CH biosorbent successfully removed more than 90% of CV and BF from real water samples, highlighting its promise as a sustainable and environmentally friendly biosorbent for water purification.

Aqueous zinc‐ion batteries (AZIBs) have attracted considerable attention as a safe and cost‐effective to energy storage system. Cathode materials, which are critical to determining overall AZIB performance, remain a major hurdle to deployment. Currently, substantial energy is required for synthesis, while improvements in capacity and energy density remain necessary to compete with incumbent lithium‐ion batteries. Herein, we report a high‐performance and durable alkali metal (M = K, Na, Li) and water co‐intercalated vanadium oxide (M‐WiVO) cathode synthesized via a rapid (70 min) and energy‐efficient plasma‐assisted hydrothermal (PAHT) process. The M‐WiVO structure consists of water‐intercalated vanadium oxide (V ₂ O ₅ ·nH ₂ O) and monoclinic M _x V ₂ O ₅ phases, which provide expanded channels for rapid Zn ²⁺ ion transport. Among the M‐WiVO materials, K‐WiVO delivers the highest capacity of 526.7 mAh g ⁻¹ at 0.1 A g ⁻¹ (≈90% of the theoretical capacity of V ₂ O ₅ ) and retains 94.5% of its initial capacity after 4000 cycles at 10 A g ⁻¹ . Density functional theory (DFT) calculations confirm the stability of the dual‐intercalated framework and the superior performance of K‐WiVO. Overall, the monoclinic M _x V ₂ O ₅ phase provides long‐term electrochemical stabilities; meanwhile, water intercalation in V ₂ O ₅ provides high capacity and facilitates the Zn ²⁺ ion transport, where the dual phase works synergistically to preserve the excellent AZIB performances in M‐WiVO.

Herein, a novel copper-triazole derivative Schiff base nanocomplex (HIT-Cu ²⁺ ) was obtained via the reaction of the 3-(2-(4-amino-5-mercapto-4 H-1,2,4-triazol-3-yl)hydrazineylidene)indolin-2-one (HIT) Schiff base with CuCl ₂ .6H ₂ O. The non-ionic surfactant Triton X-114 (TX-114) was used as the extractant. The HIT, HIT-Cu ²⁺ , and HIT-Cu ²⁺ in the organic layer were characterized by several techniques, including CHNS elemental analysis, ultraviolet-visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FT-IR), and transmission electron microscopy (TEM). The TEM results revealed the formation of the HIT-Cu ²⁺ nanocomplex, with a particle size ranging from 13 to 25 nm. Moreover, an improved preconcentration method, named rapidly synergistic cloud point extraction (RS-CPE), was established for Cu ²⁺ preconcentration and determination to overcome the issues investigated in CPE. Decanol acted as a cloud point revulsant and synergistic reagent, lowering the cloud point temperature (CPT) of TX-114, so that CPE could be done at room temperature without heating. Compared with traditional CPE (about 30 min for heating, incubation and cooling), RS-CPE was accomplished in 1 min with considerably high extraction efficiency. The improved extraction technique, RS-CPE, was combined with ICP-OES to improve the analytical performance and expand the application of ICP-OES determination. Various parameters that influence the Cu ²⁺ removal efficiency (R, %) utilizing HIT Schiff base were investigated, including the solution’s pH and volume, the concentration of HIT and Cu ²⁺ , type of surfactant, TX-114 concentration, equilibrium temperature and time, interfering ions, and centrifugation time and rate. At optimum conditions, the Cu ²⁺ linear range, the correlation coefficient, the limit of detection (LOD), and the limit of quantification (LOQ) were 0.5–5 µg.mL ^− 1 , 0.9999, 0.018, and 0.054 µg/L, respectively. The investigated RS-CPE/ICP-OES approach was applied to real water and pharmaceutical samples, achieving recoveries higher than 97% with a preconcentration factor of 125. The HIT-Cu ²⁺ CPE mechanism in the organic layer of TX-114 is elucidated. The greenness of the methods was evaluated using two recent methods: the Analytical Greenness (AGREE) calculator and the Blue Applicability Green Index (BAGI), which produced results in the ranges of 0.64–0.71 and 60-67.5, respectively. These results are strongly aligned with both green ideals and environmentally friendly practices. The predicted toxicity of HIT and HIT-Cu ²⁺ nanocomplex was evaluated using PROTOX 3 software.

In this study, we explored the overall enhancement of cellulose acetate (CA) UF performance (i.e., permeation, antifouling, antibacterial, and dye rejection properties) through incorporation of AgFeO ₂ nanoparticles (NPs) in the membrane matrix. The prepared nanocomposite membranes featured an asymmetric, sponge-like structure with random distribution of AgFeO ₂ NPs. This developed morphology altered the intrinsic characteristics compared with the neat CA membrane. For instance, the nanocomposite membrane (M5) containing 8 wt% (of AgFeO ₂ NPs possessed the lowest contact angle (42.68°), and the highest negative zeta potential of -24.9 mV. This was reflected on the pure water permeability (PWP) and bovine serum albumin (BSA) permeability (4.813 LMH·bar⁻ ¹ and 4.37 LMH·bar⁻ ¹ , respectively). In experiments for BSA, MB, and CV dye rejection, the same membrane achieved rejection rates of 51.1%, 64.4%, and 93.7%, respectively. In addition, this membrane showed excellent reusability, as indicated by a high flux recovery ratio (FRR) of 94.12% after three cycles and a low total fouling ratio, with a significant portion being reversible fouling and reduced hydraulic resistance. Strong antibacterial performance and filtration efficiency against S. aureus and E. coli is another additional asset of this membrane. In summary, AgFeO ₂ NPs served as effective modifier for CA UF membrane, enhancing its permeation, antifouling, antibacterial, and dye removal capabilities without compromising the rejection performance. Graphical Abstract