Upcycling of Expanded Polystyrene Wastes into Reusable High-Performance Volatile Organic Compound Adsorbents

Recent research indicates that plastic and water pollution have emerged as serious environmental concerns. Our goal is to convert waste into valuable resources by repurposing it for high-value applications. In this study, we transformed discarded expanded polystyrene (EPS) into a high-performance adsorbent. We developed porous recycled expanded polystyrene (PREPS), derived from waste EPS via a one-step Friedel-Crafts reaction using various crosslinking strategies. This material exhibits exceptional adsorption capacity for volatile organic compounds (VOCs), particularly for aromatic pollutants such as xylenes and toluene. The combination of its high surface area and micro/mesoporous structure, along with its hydrophobic nature, enhances its performance even under high-humidity conditions (relative humidity (RH) 80 %). Notably, the prepared polymers, PREPS-formaldehyde dimethyl acetal (FDA)/dichloroethane (DCE) and PREPS-DCE, demonstrated high adsorption capacities for xylenes (537 and 398 mg/g) and toluene (470 and 317 mg/g), respectively, outperforming conventional adsorbents like activated carbon. This study underscores the potential of upcycling waste plastics into high-performance adsorbents, providing a sustainable solution for environmental remediation.