University of Kashan Journal of Nanostructures 2251-7871 15 2 2025 04 01 Copper Ion Removal from Aqueous Media Using a Dual-Polymer Hydrogel Nanocomposite: A Sodium Alginate and Acrylamide Approach 543 554 114823 10.22052/JNS.2025.02.015 EN Ali M. Mohamed Department of chemistry, College of sciences, University of Babylon, Iraq Eateman Salah Mahdi Department of chemistry, College of sciences, University of Babylon, Iraq Safaa Mustafa Hameed Department of Optics Technologies, College of Health & Medical Technology, Sawa University, Almuthana, Iraq Uday Abdul-Reda Hussein Department of pharmaceutics, College of Pharmacy, University of Al-Ameed, Iraq Usama S. Altimari Department of Medical Laboratories Technology, AL-Nisour University College, Baghdad, Iraq Aseel M. Aljeboree Department of chemistry, College of sciences, University of Babylon, Iraq Ayad Fadhil Alkaim Department of chemistry, College of sciences, University of Babylon, Iraq Journal Article 2025 01 19 Polysaccharides represent a vital category of materials with broad applications across diverse fields such as agriculture, the food industry, biomedical engineering, and environmental remediation, owing to their distinctive and versatile characteristics. This research investigates the development of a hydrogel utilizing sodium alginate, a cost-effective and environmentally friendly polysaccharide, as the primary polymeric framework. The hydrogel was synthesized via the incorporation of acrylic acid (AA) and acrylamide (AM) monomers, utilizing potassium persulfate (KPS) as an initiator and N, N-methylenebisacrylamide (MBA) as a crosslinking agent. The resultant hydrogel’s morphology and properties were comprehensively analyzed using techniques including FESEM, TEM, XRD, and TGA. The synthesized hydrogel demonstrated notable efficacy in the removal of Cu(II) ions from aqueous solutions, exhibiting promising adsorption capabilities. The maximum adsorption capacity for Cu(II) ions was found to be 0.155 mg/g at 25 °C. Adsorption isotherm analysis revealed that the experimental data aligned well with the Freundlich isotherm model, suggesting a multilayer adsorption process, while the Langmuir isotherm suggests a monolayer. The adsorption process is physical adsorption. The Freundlich isotherm’s 1/n parameter indicates a favorable interaction between the hydrogel and Cu(II) ions. Thermodynamic analysis revealed a positive enthalpy change (∆H), indicating the endothermic nature of copper ion adsorption, and a negative Gibbs free energy change (∆G), confirming the spontaneity of the process. The substantial increase in entropy (∆S) suggests enhanced disorder at the solid-liquid interface during adsorption. Moreover, the adsorption process was observed to be spontaneous at higher temperatures, given the conditions of ∆H > 0 and ∆S > 0. https://jns.kashanu.ac.ir/article_114823_64a2d966fb19adeeed5bc3612f1d4993.pdf