Publications Internationales

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    Eco-friendly Ca/α-Fe2O3/ZnO/CuO nanocomposite: Green synthesis, characterization, and high-efficiency heavy metal removal from contaminated sludge
    (John Wiley and Sons Inc, 2025) Saoud, Abdesselam; Bouafia, Abderrhmane; Meneceur, Souhaila; Younsi, Ferroudja
    This study explores the green synthesis of Ca/α-Fe2O3/ZnO/CuO nanocomposite using Mentha pulegium L. leaf extract as a bioreducing and stabilizing agent for eco-friendly remediation. XRD confirmed a multiphase crystalline structure—cubic Ca, rhombohedral α-Fe2O3, hexagonal ZnO, and monoclinic CuO—with an average crystallite size of 24.42 ± 3.07 nm. SEM revealed ~50 nm agglomerated nanoparticles with rough surfaces, enhancing catalytic reactivity. FTIR identified metal–oxygen bonds (FeO, ZnO, CuO, CaO) and plant-derived functional groups, confirming stabilization. UV–Vis showed strong absorption at 275 nm with direct (3.07 eV) and indirect (1.70 eV) bandgaps, suitable for UV/visible-light applications, and the low Urbach energy (0.211 eV) further reflected the material's high crystallinity. TGA-DSC demonstrated 49% residual mass at 1200°C, reflecting strong thermal stability. A zeta potential of −29.06 mV ensured colloidal stability. The nanocomposite efficiently removed heavy metals from petroleum sludge, achieving 84.1% (Pb), 74.6% (Zn), 72.3% (Se), and 73.7% (Cr), while arsenic removal was relatively lower at 24.9%, highlighting current adsorption challenges. Adsorption involved diffusion and chemical fixation, underscoring potential in remediation, photocatalysis, and optoelectronics
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    Liquid-liquid extraction and simultaneously spectrophotometric determination of Co (II) and W (VI) using crown ether (DB-18-C6) in aqueous media and in high speed steel
    (Taylor and Francis Online, 2020) Saoud, Abdesselam; Hammadou née Mesdour, Souad; Arzu, Nabieva; Boudjema, Hamada; Abdeltif, Amrane; Nabiev, Mohamed
    An analytical reagent ether crown DB-18-C-6 was extensively used forthe simultaneous and individual extraction and spectrophotometricdetermination of the tungsten and cobalt at microgram levels. Theligand reacts with two metals, and the ion-association systems wereextractable into chloroform giving a yellowish [(DB-18-C-6∙NH4)+2[WO(SCN)5]2]and[(DB-18-C-6∙NH4)+2[Co(SCN)4]2-]complexes.Theabsorption peaks of these complexes were found overlapping atλmax of 415 nm and 621.6 nm, respectively. Under optimum condi-tions, the [WO(SCN)4]2-] complexation and extraction are possible onlyin concentrated medium (2.5 M of HCl). While, the [Co(SCN)4]2-]wasextractable at a pH range of 4–10. The linear ranges were 29.45–-147.25μgmL−1for Co(II) and 1.8–183 μg/mL for W(VI) with molarabsorptivity,ε=1.7×104andε=1.6×104dm3mol−1cm−1,respec-tively. The accuracy and reproducibility of the proposed method forvarious amounts of cobalt and tungstenintheirbinarymixtureweretested, and the effects of diverse ions on their extraction were alsoinvestigated. The developed method was successfully applied for thesimultaneous determination of Co(II) and W(VI) in high-speed steel(HS2-9-1-8) containing 2% W, 9% Mo, 1% V, and 8% Co.