Enhancing Hydrocracking Catalyst Performance and Lifetime through Surfactant-Templated Mesoporosity in Pt/HUSY Zeolites

Abstract

The development of catalysts capable of overcoming mass transport limitations remains a crucial challenge in hydrocracking processes, particularly for bulky linear hydrocarbons, such as long-chain paraffins. In this study, we report the synthesis of hierarchical Pt/HUSY catalysts via a surfactant-templating strategy that introduces highly interconnected intracrystalline mesoporosity while preserving most of the zeolite’s crystallinity and acidity, significantly enhancing molecular diffusion, facilitating better access to acid sites, and alleviating the diffusion limitations typically associated with purely microporous zeolites. Catalytic testing revealed a marked increase in hexadecane cracking activity, especially in catalysts with longer surfactant treatment times (Pt/CBV780_20h and Pt/CBV720_41h), which exhibited superior conversion rates and selectivities toward lighter hydrocarbons. Notably, the surfactant-templated catalysts achieved similar product distributions at lower temperatures than those of their parent materials. Additionally, our study demonstrates the importance of well-connected intracrystalline mesoporosity in reducing catalyst deactivation by preventing coke accumulation, particularly in high-aluminum Pt/CBV720 catalysts, which showed higher stability over time despite greater coke deposition. These findings highlight the effectiveness of surfactant-templated mesoporosity as a powerful strategy to enhance both the performance and lifetime of zeolite-based catalysts for industrial hydrocarbon conversion processes.