Friedel–Crafts acylation of anisole and toluene with acetic anhydride over nano-sized Beta zeolites

摘要

Nano-sized Beta zeolites, with a crystal size of 80–100 nm, were synthesized via surface wet method. The nano-sized HBeta zeolites exhibit much higher activity and stability in the Friedel–Crafts acylation of anisole and toluene with acetic anhydride than the conventional zeolites of large particle size. The small crystal size of nano-sized zeolites may bring on more accessible active sites and then enhance the catalytic activity. The exposed pore openings in nano-sized zeolites allow a fast desorption of heavy products from the catalyst and can then reduce the occupancy of active sites by the adsorption of products; this can then alleviate the catalyst deactivation and improve the catalyst stability.