Preparation, Characterization, and Application of Polyacrylamide‐Polystyrene/Bentonite Nanocomposite as an Effective Immobilizing Adsorbent for Remediation of Soil

Abstract Heavy metals are among the most important environmental pollutants. However, little attention has been devoted to immobilizing or fixing metal ions in soil for remediation of soil. Here, a novel and inexpensive, polymer nanocomposite (polyacrylamide‐polystyrene/bentonite) is introduced for successful immobilization of cadmium (Cd) and lead (Pb) cations in the soil. The synthesized nanocomposite structure was characterized by X‐Ray Diffraction (XRD), Field Emission Scanning Electron Microscopy/Energy‐Dispersive X‐Ray Spectroscopy (FE‐SEM/EDX), Transmission Electron Microscopy (TEM), Brunauer‐Emmett‐Teller (BET), and Fourier‐Transform Infrared Spectroscopy (FT‐IR). Various effective parameters such as pH, bentonite: polyacrylamide weight ratio, heavy metal concentration, and amount of adsorbent were investigated for fixing Pb and Cd cations in farm soil. Also, adsorption isotherms and kinetics of adsorption were investigated. Finally, under optimum conditions, the extent of adsorption of Pb and Cd cations by polyacrylamide‐polystyrene/bentonite nanocomposite, polyacrylamide, and bentonite was compared. The results revealed the superior adsorption activity of the nanocomposite for immobilizing heavy metal cations as compared to bentonite or polymer. Further, the nanocomposite indicated a reasonable reusability for fixing Cd and Pb cations. Overall, the prepared nanocomposite can be applied as a suitable and industrial adsorbent for immobilizing Pb and Cd cations in soil.