Upcycling Polyethylene Waste to Advanced Carbon Materials for Energy Storage Applications

Conference · Thu Nov 07 04:00:00 EST 2024

DOI:https://doi.org/10.2172/2476286· OSTI ID:2476286

Gao, Yuan ^[1]; Pham, Viet Hung ^[1]; Huynh, Ngoc Tien ^[1]; Wang, Congjun ^[2]; Kim, Ki-Joong ^[2]; Matranga, Christopher ^[2]

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1. NETL Site Support Contractor, National Energy Technology Laboratory
2. NETL

Polyethylene is notoriously difficult to upcycle because it decomposes into light gases at approximately 350-400 °C which prevents processing it at higher temperatures to convert it into high-value carbon materials, such as graphene or graphite. We address this challenge by using an air-based, thermo-oxidation process, which heats polyethylene (PE) just below the decomposition point to initiate oxidation and cross-linking of PE alkyl chains. These molecular transformations allow PE to be further graphenized or graphitized at higher temperatures without decomposing. The PE-derived graphene has a specific surface area up to 1,800 m 2/g and Raman ID/IG ratio of 0.85, which enables it to be used as an electrode material for a symmetric supercapacitor with the 1 M H2SO4 electrolyte. The PE-derived graphene material has a comparable electrochemical capacitive performance, such as power density, specific capacitance, and long cycle stability, to the commercial state of art porous carbon electrode. The stabilized PE could also be converted into highly crystalline flake graphite via low-temperature catalytic graphitization. The PE-derived graphite is used for the lithium-ion battery anode, which showed comparable electrochemical battery performance, such as reversible rate performance and long-term cyclic stability, to the current use battery-grade graphite, thus providing a scalable method to upcycle PE plastic waste into high-value carbon material.

• Research Organization: National Energy Technology Laboratory (NETL), Pittsburgh, PA, Morgantown, WV, and Albany, OR (United States)
• Sponsoring Organization: USDOE Office of Fossil Energy and Carbon Management (FECM); USDOE Office of Fossil Energy and Carbon Management (FECM), Office of Resource Sustainability (FE-30)
• OSTI ID: 2476286
• Country of Publication: United States
• Language: English