Synthesis of Trioctyl Citrate Catalyzed by p-toluene Sulphonic Acid Supported on Palygorskite

Catalyst,p-toluene sulphonic acid supported on acid activated palygorskite,is prepared via adsorption through reflux and evaporation;the resulted catalyst is characterized by FTIR,XRD spectroscopy.Several factors including the concentration of acid treated on palygorskite,the quantity of p-toluene sulphonic acid supported on the supporter,the amount of catalyst,the ratio of acid to alcohol and reaction times are discussed by means of single factor experiment to get the optimal reaction condition for the synthesis of trioctyl citrate.The yield could reach 96.7% as the molar ratio of citric acid to n-octyl alcohol is 1∶5,the reaction time is 1.5 h,mass of catalyst is 0.8 g,the reaction temperature is at 150 ℃ and the amount of citric acid is 0.025 mol.This kind of catalyst is relatively active and can be easily separated from the reaction system.