Integrating Pore Interconnectivity and Adaptability in a Single Crystal Hierarchical Zeolite for Liquid Alkylation

Abstract

Zeolite belongs to one of the most important families of solid acid catalysts in chemical industries. It is however severely constrained by the diffusion limitation for bulky molecules, the lack of multi-functionality for sequential reactions and pore adaptability towards specific adsorbates, due to the small micropore size and simple aluminosilicate framework. Introducing mesopores into the zeolitic framework towards hierarchical zeolites is prevailing, but usually suffers from compromised crystallinity as well as insufficient interconnectivity and openness of mesopores. Herein, a novel of acid-redox co-functionalized single-crystalline zeolite with highly open and interconnected mesopores is designed and fabricated. As a proof-of-concept study, we integrate the solid acid and Fe-oxy redox sites in a hierarchical MEL zeolite with well characterized microporosity and mesoporosity. It exhibits superior activity and stability towards the alkylation between mesitylene with benzyl alcohol, arising from greatly facilitated intracrystalline molecular diffusion, mitigated metal leaching and optimized adsorbate-pore wall interactions.