Aminoacid-Assisted Synthesis of Hollow Hierarchical FER Zeolite with Improved Catalytic Performance.

Abstract

Hierarchical zeolites are highly-desired catalysts in the petrochemical industry due to their shorter diffusion length, faster diffusion rate, and better accessibility to active acid sites compared with conventional zeolites. Herein, we report a simple aminoacid-assisted method to synthesize urchin-like hollow hierarchical FER zeolite with abundant mesopores and macroporous inner cavities. An aminoacid (i.e. L-lysine) is used to facilitate the agglomeration of primary nanoparticles, and the agglomerates with staged crystallization in the internal and surface. The preferential nucleation and crystal growth at the external surfaces together with the lagged crystallization of the inner core of the agglomerates results in the formation of hollow inner cavities after the exhaustion of interior materials. Thanks to the unique hierarchical structure and more accessible acid sites, the hollow hierarchical FER zeolite exhibits improved catalytic performance over the conventional one in the skeletal isomerization of 1-butene to isobutene.