Synthesis of n-butyl p-hydroxybenzoate with sodium bisulfate supported by silica

Preparation of n-butyl p-hydroxybenzoate by the esterification of p-hydroxy benzoic acid and n-butanol using sodium bisulfate as a catalyst supported by silica was reported. The influences of some factors on the synthesis process were studied. The optimal reaction conditions were chosen that the molar ratio of n-butanol and p-hydroxy benzoic acid was 3:1, the mass ratio of catalyst to reactants was 5%, reaction time by refluing was 3 hours. The yield of the product reached 96.2%. The structure of n-butyl p-hydroxybenzoate was characterized by IR spectrum. The catalyst could be recycled and used for many times.