Study on the Synthesis of p-Hydroxybenzoate Catalyzed by Potassium Bisulfate

Using p-hydroxybenzoic acid and n-butanol as starting materials, potassium bisulfate as catalyst, the butyl p-hydroxybenzoate was synthesized via direct esterification without any water-carrying agent. The results indicated that the molar ratio of alcohol to acid was 25:1, amount of potassium bisulfate was 5% to the reactants, reaction time was1.5h, and the yield of the butyl p-hydroxybenzoate was up to 96.8%.The reusability of catalyst potassium bisulphate was fairly good through investigation. And seven p-hydroxybenzoates based on different fatty alcohols were synthesized under aforementioned optimum reaction conditions, the yields of final products can be reached 68.4%-89.5% separately.