Improved performance of nano-size H-BEA zeolite catalysts for the Friedel-Crafts acetylation of anisole by acetic anhydride

Nano-size zeolite H-BEA (n-H-BEA) prepared by "confined space synthesis'' (CSS) within the pores of a carbon black matrix shows improved activity without loss in para-selectivity for the Friedel-Crafts acetylation of anisole by acetic anhydride. The turnover frequency (TOF) of n-H-BEA exceeds that of a conventional H-BEA catalyst of similar aluminum and thus acid site content by a factor of about three at intermediate conversion. The latter observation is attributed to enhanced access and better utilization of the whole zeolite intracrystalline volume by the reactants as well as to the easier desorption of the acetylated product, p-methoxyacetophenone.