Polyacrylamide Hydrogel an Effective Adsorbent for the Removal of Heavy Metal from Aqueous Solution: Isotherm, Kinetic, and Thermodynamic Studies
Imane Lebkiri, Brahim Abbou, Lamya Kadiri, Abdelkarim Ouass, Youness Essaadaoui, Hanae Ouaddari, Ahmed Lebkiri, El Housseine Rifi
Abstract
Crosslinked polyacrylamide hydrogel was used in the adsorption of heavy metals; lead, copper, and cadmium. The effect of different parameters, pH, temperature, and concentration of the metallic solution on the adsorption were studied. The metal ion removal capacities changed depending on the nature of the metal, the PAAM hydrogel were highly selective to Pb(II) ions. Under optimal conditions, the maximum adsorption capacity of Pb(II) Cu(II), and Cd(II) were 442.31, 331.59, and 216.26 mg/g, respectively. In addition, the research of kinetics and isotherms displayed that the pseudo-second-order kinetic model and the Langmuir isotherm model fitted the data well regardless of the adsorbed metal studied. PAAM was also regenerated over multiple adsorption cycles without any appreciable loss of its adsorption capacity.