Catalytic synthesis of ethyl propionate by copper p-toluene sulfonate

Catalytic esterification reaction of propionic acid with ethyl alcohol by copper p-toluene sulfonate has been studied.The effects of the mole ratio of alcohol to acid,the amount of catalyst and reaction time in the reaction have been investigated.Results showed that the appropriate conditions were: Molar ratio of ethyl alcohol to propionic acid was 1.5∶1;1.8(mol)% catalyst(molar percent of propionic acid);Reaction time was 2.0h at reflux temperature;The esterification yield reached to 93.6%. Copper p-toluene sulfonate can be reused by simple phase-separation,No need of regeneration,It has merits of both homogeneous and heterogeneous catalyst.