Removal of heavy metals from aqueous solution by poly(acrylamide-co-acrylic acid) modified with porous materials

In this study, a series of poly acrylamide-co-acrylic acid/NaY zeolite, poly acrylamide-co-acrylic acid/MCM-41, and poly acrylamide-co-acrylic acid/clinoptilolite nanocomposites were synthesized. These materials were characterized by using FT-IR spectroscopy, XRD, TGA, and SEM. Removal capacity of Pb(II) and Cd(II) ions in aqueous solutions by using these nanocomposites was investigated with controlled time, initial metal ions concentration, pH values, adsorbent content, and temperature by using atomic absorption spectrometry. Results show that these nanocomposites have further adsorption related to NaY, MCM-41, and clinoptilolite. Poly(AAm-co-AAc)/NaY, poly(AAm-co-AAc)/MCM-41, and poly(AAm-co-AAc)/clinoptilolite exhibit superior Pb(II) (about 90-99%) and Cd(II) (about 88-98%) adsorption behavior at room temperature and the poly(AAm-co-AAc)/NaY nanocomposite had the best adsorption behavior. Finally, the equilibrium removal performance of the composites is analyzed according to the Langmuir and Freundlich adsorption isotherm model that shows result fitted to Langmuir model and have monolayer adsorption.