Synthesis of triethoxysilane imidazolium based ionic liquids and their application in the preparation of mesoporous ZSM-5

Abstract

Triethoxysilane containing imidazole based ionic liquids were synthesized. These ionic liquids were utilized as a structure directing agent for the synthesis of mesoporous ZSM-5. ZSM-5 was characterized by a complementary combination of X-ray diffraction, N2 adsorption/desorption, Scanning electron microscopy, Transmission electron microscopy, Temperature programmed desorption techniques, Infrared spectroscopy and Nuclear Magnetic Resonance spectroscopy. The resultant zeolites were mesoporous and showed unique characteristics of a fully crystalline microporous MFI zeolite framework. Mesoporous ZSM-5 synthesized from imidazole based ionic liquids exhibited higher catalytic activity than conventional ZSM-5 in alkylation and cracking reactions. Significantly high catalytic activity of the mesoporous ZSM-5 suggests that large external surface area and accessible acid sites are beneficial for catalytic reactions involving large organic molecules.