Abstract

Plastic waste, a significant environmental challenge due to its nonbiodegradability, is being transformed as a valuable solution for water treatment while promoting a circular economy. In this study, polyurethane extracted from plastic waste (code 7) was used to fabricate polymeric adsorbents (PWPA) and silica-modified adsorbents (Si-PWPA) through a single-step process using toluene as a solvent. These adsorbents were used to adsorb As(III) ions from contaminated water. The adsorbents were characterized using HRMS, FTIR, SEM-EDX, and XRD techniques, while atomic absorption spectroscopy (AAS) measured the AS(III) concentrations. The HRMS confirmed successful polyurethane extraction, and characterization revealed porous structures conducive to enhanced adsorption. Density functional theory (DFT) provided insights into the adsorbents' geometrical and energetic molecular properties. The maximum adsorption capacities for PWPA and Si-PWPA were 107.52 and 166.66 mg/g, with 67% and 98.78% removal efficiencies, respectively, at pH 7 over 90 min. These results demonstrate that the adsorbents derived from plastic waste offer a cost-effective and efficient method for arsenic removal, providing a dual solution to environmental pollution through waste recycling.