Engineering porous Beta zeolite-encapsulated nickel catalyst for waste polyolefins upcycling

Upcycling plastic wastes through hydrocracking represents an efficient and promising way to produce high-value fuels and chemicals, which faces significant challenges using non-noble metal catalysts . Here, we reported a closed-loop strategy using 10Ni@Beta catalyst to convert low-density polyethylene (LDPE) into naphtha (C 5 -C 9 hydrocarbons), a major feedstock to reproduce polyolefins . The hierarchically porous Beta zeolite was constructed while encapsulating 10 % Ni loading through controlled dissolution-recrystallization. An 88.0 % liquid yield was obtained and the selectivity of naphtha reached 99.1 % at 250 °C within 2 h reaction, surpassing previously reported Pt-based catalysts. The engineered meso-microporous architecture with confined Ni nanoparticles mimicked the mechanism of enzyme-catalyzed process, where the initial cracked LDPE fragments at surface acid were selectively transferred into mesopore channels and further screened by micropores with suitable size to contact Ni sites for hydrogenation. This designed porous catalyst matched the tandem catalytic process of multiple real-life polyolefins , enabling the industrial upcycling of plastic wastes. LDPE was efficiently hydrocracked into C 5 -C 9 hydrocarbons with the highest yield of 87.2 % by encapsulating 10 % Ni loading into meso-microporous 10Ni@Beta catalyst, serving as the raw materials for plastic reproduction. • Polyolefins are hydrocracked into naphtha with non-noble 10Ni@Beta catalyst. • The meso-microporous structure is constructed with encapsulation of 10 % Ni loading. • A remarkable 88 % liquid yield with 99 % C 5 -C 9 alkanes is obtained at mild conditions. • Balanced Beta zeolite and confined Ni nanoparticles boost the shape selectivity.