Degradation-catalysis of polypropylene into liquid fuel-range iso-olefins using Zn and Ni-incorporated microporous...

The widespread use of plastic materials in modern society has led to the substantial accumulation of end-of-life plastic waste. Among these, waste polypropylene (PP) poses a particularly significant environmental challenge due to its chemical recalcitrance and inert C-C backbone. Chemical upcycling of plastic waste has emerged as a promising strategy to support sustainable development and promote a closed-loop material economy. This study presents a degradation-catalysis strategy for upcycling PP waste using Zn and Ni-incorporated microporous carbonaceous catalysts. A series of metal-doped catalysts (M/Cs) with varying Zn and Ni loadings were evaluated, among which the bimetallic Ni-Zn/C catalyst exhibited the highest selectivity toward gasoline-range hydrocarbons (81.87 mol%). Moreover, Zn-incorporated carbonaceous catalyst (Zn/C) was more effective in producing sustainable aviation fuel (SAF)-range species, achieving a selectivity of 73.71 mol%. The introduction of metal salts not only promoted the development of porous structures but also enriched the surface with Lewis acid sites, thereby enhancing radical formation and β-scission pathways for light hydrocarbon production. In summary, this study provides valuable insights into a green and efficient pathway for plastic waste upcycling, contributing to sustainable fuel production.