Facile control of crystallite size of ZSM-5 catalyst for cracking of hexane

Abstract

Nano-sized H-ZSM-5 ( ca. ∼65 nm) was successfully prepared by mixing the mother gel under mild conditions before crystallization. Furthermore, a facile control of the crystallite size of the H-ZSM-5 catalyst was achieved merely by changing the amount of water in the mother gel. Three different-sized H-ZSM-5 catalysts were used as a catalyst for hexane cracking at 723–923 K. The crystallite size of H-ZSM-5 little affected the initial activity, but affected the deactivation rate considerably. The reduction in the crystallite size of the H-ZSM-5 catalysts contributes to the slow deactivation, probably because the H-ZSM-5 with a smaller crystallite size is less sensitive to deactivation by pore blocking by coke formed.