Catalytic properties of nano-sized ZSM-5 aggregates

Abstract Nano-ZSM-5 (NZ) with well-defined porosity was synthesized by organic silica method. The material exhibited more than a twofold increase in pore volume when compared to the normal ZSM-5 (HZ). The increase in pore volume is observed in the entire range of the pores with diameter from 5 A to 1500 A. The order of increase in volume is macropores (>500 A) > micropores (up to 20 A) > mesopores (20–500 A). Although macropore and mesopore formation is responsible for the major increase in the pore volume, significant increase in zeolitic pore volume was also observed in NZ. Both the ZSM-5 materials were tested for esterification of cyclohexanol with acetic acid under autogeneous pressure conditions where NZ showed better activity (69% conversion).

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