Boosting the Application of Spent Catalysts in Waste Plastic Catalytic Pyrolysis: Maximizing Gasoline Product Selectivity and Quality

Abstract Catalytic pyrolysis is identified as a superior method for the disposal of waste plastics providing enhanced efficiency and environmental advantages compared to conventional techniques. However, the high cost of the catalytic process limits the enhancement of economic benefits. This study investigates the utilization of cost‐effective spent catalysts specifically Y zeolite, ZSM‐5 zeolite, and silica powder within a fixed‐bed/fluidized‐bed combination reactor setup to optimize the conversion of waste plastics into valuable products. The results show that the remarkable selectivity of spent Y zeolite for gasoline production achieving a yield of 52% with its pore characteristics inclined towards gasoline generation and moderate acidity sites being distinctive features. By implementing a thermal driving strategy with Y zeolite, the research further increases the C 4 fraction by 1.5 times and significantly enhances olefin isomerization within gasoline representing crucial advancements that improve both the quantity and quality of the potential gasoline. These findings provide essential insights and support for the effective reuse of spent catalysts in the catalytic pyrolysis of waste plastics underscoring the potential for sustainable waste management and resource recovery.