On the introduction of intracrystalline mesoporosity in zeolites upon desilication in alkaline medium

The development of considerable mesoporosity Without destruction of the intrinsic zeolite properties has been attained in various commercial zeolites by treatment in alkaline medium. Zeolites MFI, BEA, MOR and FER appear to be susceptible to extensive mesopore formation by extraction of framework Si in the parent material (desilication). Each structure requires particular treatment conditions. Variation of treatment time and temperature enables tailoring of the mesopore size and volume leading to hierarchical porous materials. The versatility of this alkaline treatment opens new avenues to improve diffusion characteristics in zeolite-catalyzed applications. (C) 2004 Elsevier Inc. All rights reserved.