Synthesis of tributyl citrate with sodium bisulfate as catalyst

Tributyl citrate was synthesized with citric acid and n-butyl alcohol as raw materials and using p-toluene sulphonic acid supported on active carbon as catalyet.The effect faetors,such as time of reaction,the dosage of catalyst,the molar ratio of cyclohexanol to acetic acid and the repeat application of catalyst were investigated to the esterification of tributyl citrate.The effect of reaction fluid to the color of the products was also studied.The optimum conditions of synthesis were determined: molar ratio of acid to alcohol was 1∶4.1,amount of catalyst was 3.5 g,reaction time was 2 h based on 0.1 mol tributyl citrate,the yield of esterification was up to 96.7%.The characterizations of products were determined by using refractive index and IR spectrum.The results showed that sodium bisulfate was the fine catalyst in synthesis of tributyl citrate,but it had poor effect when reused.