Bimetallic NiFe/Al2O3 catalyst for efficient hydrogenolysis of polyethylene into aviation fuel range alkanes

Abstract

Facing the rapidly increasing plastic waste, hydrogenolysis is an efficient method for converting it into value-added products, such as aviation fuels. With their abundant reserves and low cost, Ni-based catalysts have demonstrated significant potential to replace noble metal catalysts for the degradation of waste polyethylene. In this study, we report a bimetallic 10Ni2Fe/Al₂O₃ catalyst for the hydrogenolysis of low-density polyethylene (LDPE) to produce aviation fuel range alkanes under mild reaction conditions. This catalyst achieved a maximum liquid yield of 79%, with a selectivity of C₈–C₁₆ hydrocarbons reaching 74% at 300 °C and 3 MPa of H₂ within 5 h. The addition of Fe enhanced the dispersion of Ni nanoparticles and increased the rate of internal C−C bond cleavage, thereby suppressing the formation of CH₄ and improving the selectivity of C₈−C₁₆ alkanes. With Fe doping, the reaction rate increased 2.5 times, and the ratio of end to internal C–C bond cleavage dropped from 2.86 to 1.29. These results indicate the feasibility of upcycling polyethylene into aviation fuel range alkanes using a non-noble metal catalyst, providing a new pathway for the utilization and upcycling of plastic waste.