Synthesis of hierarchical porous zeolite and its performance in n-heptane cracking

Abstract: A series of hierarchical porous zeolites (ZSM-5–ZRP-1) was synthesized by adding different contents of ZRP-1 to the procedure of hydrothermal synthesis of ZSM-5. The prepared samples were characterized by using N2 adsorption–desorption, XRD, SEM, TEM, NH3-TPD, Py-FTIR and investigated in cracking of n-heptane. The results indicate that physicochemical properties and catalytic performances of ZSM-5–ZRP-1 samples are quite different from those of HZSM-5 or ZRP-1. ZSM-5–ZRP-1 samples have a lot of mesopores and suitable amount of B+L acid sites as well as higher L/B ratio compared with HZSM-5 or ZRP-1, and also show medium acid amount and strength. These lead to a higher selectivity of olefins (ethylene plus propylene) obtained on it. [Copyright &y& Elsevier]