Catalytic activity of anion-modified zirconia,alumina and silica in the esterification of benzyl alcohol with acetic acid

摘要

The catalytic activity of zirconia,alumina and silica and their sulphate,phosphate and borate modified forms has been studied in the liquid phase esterification of benzyl alcohol with acetic acid for the synthesis of benzyl acetate.All these catalysts have been found to be active for the formation of benzyl acetate with 100% selectivity.A small amount of dibenzyl ether was formed only in the case of sulphated zirconia when refluxed for more than 12 h.The active sites with 'weak to intermediate' acid strengths may be responsible for the catalytic activity towards the esterification.Sulphated zirconia is the most suitable catalyst providing 53 to 90% yield of benzyl acetate when refluxed for 30 min to 24 h with 0.1 to 3 g of the catalyst.This catalyst has been found to be effective in catalyzing the esterification of n-propanol,iso-propanol,n-butanol and iso-butanol with acetic acid to form the respective esters in good yields.