(704b) Microwave-Catalyzed Selective Upcycling of Single-Use Polyethylene Films to Light Olefin

The accumulation of single-use polyethylene (PE) film waste has become a pressing environmental issue due to its widespread use, low recyclability, and resistance to degradation. These thin, flexible plastic films, commonly found in packaging and disposable products, contribute significantly to the global plastic waste crisis. Although catalytic depolymerization is a promising route for plastic waste valorization, achieving high selectivity toward light olefin from PE film waste under mild conditions remains a major challenge. In this work, we present a highly efficient and selective microwave-assisted catalytic upcycling process for converting single-use PE films into light olefins.

Using a Fe-based catalyst, complete conversion of PE films (100%) and a light olefin yield over 70 wt.% were achieved at 400 °C and ambient pressure under microwave irradiation. In contrast, conventional thermal treatment of PE films under identical conditions resulted in no conversion, and even at 600 °C, the light olefins yield was limited to 64 wt.% despite full PE conversion.

The catalytic system exhibited excellent stability and recyclability under microwave conditions. Density functional theory (DFT) calculations further elucidated the crucial role of microwave-specific effects and catalyst-microwave interactions in promoting selective depolymerization of PE film waste. This work offers a scalable and sustainable solution for transforming single-use PE films into valuable chemical feedstocks, addressing a critical challenge in plastic waste management.