Synthesis of methyl oleate catalyzed by Brφnsted acid ionic liquids

Two kinds of Brφnsted acid ionic liquids(HSO4,HSO4) were synthesized and characterized,the catalytic activities of the acidic ionic liquids for the synthesis of methyl oleate were also investigated.The results showed that the catalytic activity of ionic liquid was closely related to its acidity;under the conditions of molar ratio of methanol to oleic acid 1.5∶1,HSO4 dosage 5% in the weight of oleic acid,temperature 75℃ and time 3 h,the yield of methyl oleate reached 98%without removal of water during the esterificaion.After reaction,the ionic liquid and esters were separated to two phases in nature.When the ionic liquid of HSO4 was reused 5 times,it still remained a higher catalytic activity.