Light bulb-inspired high-temperature catalytic depolymerization of polyolefin plastic with high monomer selectivity

The accumulation of plastic waste poses a severe environmental issue, and efficient depolymerization of plastic is essential toward sustainable waste management and circularity. However, depolymerizing polyolefin plastic into monomer with high selectivity remains a challenge. Herein, inspired by the incandescent light bulb, we demonstrate a catalytic depolymerization strategy utilizing high-temperature transition metal filaments to convert polyolefin plastic to olefin monomer, with monomer selectivity reaching up to 65%. The electrified transition metal filaments, serving as localized heat sources, can reach a high temperature of up to 2300 °C, significantly promoting the generation of gaseous products. The reaction region with sharp temperature gradient restrains secondary transformations of monomer. Monomer selectivity is tunable by varying different high-melting-point metallic elements, and can be extended to bulk commodity alloy, such as stainless steel. Efficient depolymerization of plastic is essential to ensure waste management and circularity but depolymerizing polyolefin plastic into monomer with high selectivity remains challenging. Here the authors demonstrate catalytic depolymerization using transition metal filaments at high temperature to convert polyolefin plastic to olefin monomer, with high monomer selectivity.