Oxygen-mediated tandem polyethylene upcycling for selective aromatic synthesis

Abstract Selective chemical upcycling of waste polyethylene (PE) into high-value aromatics is conceptually very attractive. Yet, up to now the aromatic product selectivity typically remains below 50%, mainly limited by competing hydrogenolysis. We report here a cascade process that combines the selective aerobic oxidation of hydrogen, in situ generated from PE via cleavage of C(sp3)–H, with oxygen and the endothermic aromatization of polyethylene. Our tandem aerobic oxidation-aromatization approach boosts the catalytic activity at moderate temperatures of up to 280°C in ambient air. Concurrently, hydrogen removal shifts the chemical equilibrium favorably towards formation of aromatic products, achieving an aromatic selectivity of 78 mol%. Demonstrated on a near kilogram scale with upscaled catalysts under mild conditions, our approach offers a scalable, energy-efficient solution for the high-selectivity conversion of plastic waste into valuable chemical intermediates and solvents.