Kinetic, Isotherm, and Thermodynamic Modeling of Pb(II) Heavy Metals Removal from Aqueous Solutions Using Hydrogel-MWCNTs Nanocomposites

This study investigated the ability of nanocomposite hydrogels (NaCMC-g-AAc/COOH-MWCNTs) to adsorb Pb(II) ions, an environmental pollutant. The characterisation of the hydrogel and nanocomposite was achieved using FTIR, FESEM, XRD and TGA techniques, XRD techniques. Adsorption studies showed that equilibrium was reached after 120 minutes with a removal efficiency of 82%. Many factors were also studied, as the results indicated that the adsorption equality was of the (S4) type according to Giles' classification, and the adsorption parallels for Pb (II) ions matched the Freundlich adsorption model. The absorption process was found to be endothermic, with absorption increasing with increasing temperature. Positive content and entropy are noted, as well as negative free energy, indicating the physical and spontaneous nature of the process.