Catalytic application of hydrophobic properties of high-silica zeolites: I. Hydrolysis of ethyl acetate in aqueous solution

Abstract

The hydrolysis of ethyl acetate in aqueous solution over various solid acid catalysts was investigated. The activity of high-silica zeolites (H-ZSM-5, dealuminated H-mordenite) was moderate, while that of silica-alumina, nondealuminated H-mordenite, and H-Y zeolite was very small. Notably, the activity of H-ZSM-5 ( Si Al = 47 ) was high and about 40% of that of the cation exchange resin. The H-ZSM-5 had acid sites whose strength was −5.6 < H 0 ≦ −3.0 in water. The higher Si Al atomic ratio provided a more hydrophobic property on the catalytic surface, which, therefore, showed better affinity for organic materials than water. However, too high a Si Al atomic ratio resulted in the decrease in the activity, because the acid sites decreased in number.