Noble Metal-Free Low-Temperature Aromatization of Polyethylene Waste for High-Quality Fuel Production

The chemical recycling of waste plastics into high-quality fuels is highly attractive due to their similar chemical structures. Conventional methods like hydrocracking and hydrogenolysis, however, primarily yield alkanes with low octane numbers. This work presents a metal-free approach that converts polyethylene (PE) waste into fuels with tunable octane number (79-103) by leveraging a Prins reaction mediated low-temperature aromatization process, offering broad applicability for diverse combustion needs. By synchronizing CO hydrogenation rate with the aromatization of reactive dienes and oxygenates intermediates generated via the Prins reaction, up to 68% selectivity of light aromatics by weight was attained for octane number modification on a ZnZrO and ZSM-5 tandem catalytic system below 300 °C. A technical-economic analysis predicts a net post-tax profit of USD 65.3 million per year with a payback period of 3.8 years for a 200 kton per year facility, providing a scalable and cost-effective pathway to upcycle polyolefins into fuels ranging from commercial gasoline (high octane) to aviation-grade compositions.