Selective depolymerization of polyolefin copolymer via high-entropy alloy catalyzed pyrolysis in a double-layered ultrafast heating reactor

Kim, Seung Won [Sungkyunkwan University, Suwon (South Korea)]; Lee, Hansung [Yale University, New Haven, CT (United States); Ajou University, Suwon (South Korea)]; Lee, Seonho [Sungkyunkwan University, Suwon (South Korea)]; Song, Eunhyo [Ajou University, Suwon (South Korea)]; Kim, Yong Tae [Korea Research Institute of Chemical Technology, Daejeon (South Korea)]; Ahn, Byungmin [Ajou University, Suwon (South Korea)]; Vlachos, Dionisios G. [University of Delaware, Newark, DE (United States)]; Lee, Jechan [Sungkyunkwan University, Suwon (South Korea)]

doi:10.1016/j.cej.2026.177294

DOE OSTI · 3625663

Selective depolymerization of polyolefin copolymer via high-entropy alloy catalyzed pyrolysis in a double-layered ultrafast heating reactor

Kim, Seung Won [Sungkyunkwan University, Suwon (South Korea)]·Lee, Hansung [Yale University, New Haven, CT (United States); Ajou University, Suwon (South Korea)]·Lee, Seonho [Sungkyunkwan University, Suwon (South Korea)]·Song, Eunhyo [Ajou University, Suwon (South Korea)]·Kim, Yong Tae [Korea Research Institute of Chemical Technology, Daejeon (South Korea)]·Ahn, Byungmin [Ajou University, Suwon (South Korea)]·Vlachos, Dionisios G. [University of Delaware, Newark, DE (United States)]·Lee, Jechan [Sungkyunkwan University, Suwon (South Korea)]

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Abstract

Chemical recycling of polyolefin copolymers (PCPs) is essential for mitigating plastic pollution, yet achieving selective depolymerization into C 2 –C 3 monomers at high productivity remains challenging. Here, we introduce a double-layered ultrafast heating reactor (DUHR) that integrates Joule heating with a high-entropy alloy (HEA) catalyst composed of near-equimolar Co, Cu, Fe, Mn, and Ni. We achieve highly selective depolymerization of PCP into ethylene and propylene, yielding a 70% non-condensable fraction. Significant aromatic fractions form via radical-driven pathways—a behavior distinct from conventional externally heated pyrolyzers—highlighting DUHR's ability to generate reactive species and modulate reaction pathways. Furthermore, these findings demonstrate an effective strategy for chemical recycling of real-world plastic waste for polyolefin circularity and sustainable resource recovery.

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Chemical recycling Electrification Multi-principal element alloy (MPEA) catalyst Plastic waste Rapid heating Waste treatment

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Kim, Seung Won [Sungkyunkwan University, Suwon (South Korea)], Lee, Hansung [Yale University, New Haven, CT (United States); Ajou University, Suwon (South Korea)], Lee, Seonho [Sungkyunkwan University, Suwon (South Korea)], Song, Eunhyo [Ajou University, Suwon (South Korea)], Kim, Yong Tae [Korea Research Institute of Chemical Technology, Daejeon (South Korea)], Ahn, Byungmin [Ajou University, Suwon (South Korea)], Vlachos, Dionisios G. [University of Delaware, Newark, DE (United States)], Lee, Jechan [Sungkyunkwan University, Suwon (South Korea)]. 2026-07-01. Selective depolymerization of polyolefin copolymer via high-entropy alloy catalyzed pyrolysis in a double-layered ultrafast heating reactor. https://doi.org/10.1016/j.cej.2026.177294

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