Chemical recycling of polycarbonate waste into advanced aviation fuel candidates via nickel-oxygen vacancy dual sites

Abstract

Transforming polycarbonate (PC) waste to C15 dicycloalkane offers a green pathway for plastic recycling and advanced aviation fuel production. Conventional metal-zeolite catalysts rely on noble metals and suffer from diffusion limitations and coke deposition. Herein, we report cost-effective Ni/CeO2 catalysts featuring nickel-oxygen vacancy dual sites that convert PC waste into advanced aviation fuel-range hydrocarbons with 96.5% total alkane yield, including 84.4% C15 dicycloalkane. The catalyst demonstrates excellent stability, maintaining activity over four consecutive cycles with strong resistance to coke formation. It also demonstrates comparable performance when applied to real waste PC plastics. Mechanistic insights reveal a conversion pathway driven by dual active sites: (1) chain scission through C-O bond hydrogenolysis on metallic Ni, (2) stepwise hydrogenation of the resulting monomers on Ni to form C15 alcohols, and (3) deoxygenation on oxygen vacancies to yield C15 dicycloalkane. Fuel property evaluations further confirm that C15 dicycloalkane and its blends with commercial RP-3 fuel meet key specifications for advanced aviation fuel. This work positions PC waste as a promising feedstock for advanced aviation fuels and establishes an efficient conversion pathway enabled by nickel-oxygen vacancy dual sites.