Catalytic Properties of a Hierarchical Zeolite Synthesized from a Natural Aluminosilicate Mineral without the Use of a Secondary Mesoscale Template

Abstract

Abstract A hierarchical ZSM‐5 zeolite with a bimodal meso‐microporous system, high crystallinity, and a large surface area and meso‐micropore volume was successfully synthesized from a natural layered aluminosilicate mineral rectorite without using a secondary mesoscale template. The physicochemical and catalytic properties of the hierarchical ZSM‐5 zeolite were extensively characterized. The results showed that the mesopores of the synthesized hierarchical ZSM‐5, which are almost slitlike intercrystal pores, originate from the construction of primary nanorods of the ZSM‐5 zeolite. Analysis of the crystallization process revealed that the undissolved rectorite debris acted as seed crystals and played a structure‐directing role, which is the key factor that influences the formation of the hierarchical structure. Such a hierarchical ZSM‐5 zeolite, as a result of its unique structural characteristics and increased accessibility of acid sites, possessed a remarkably enhanced activity for the cracking of 1,3,5‐triisopropylbenzene, a dramatically higher anti‐deactivation ability for cumene conversion, and a significantly improved propylene‐boosting performance for heavy oil cracking than the other catalysts tested.