Monitoring of base catalyzed ethanolysis of Jatropha curcas oil by reversed phase high performance liquid chromatography assisted by ultrasonication

• Ultrasonication used for the ethanolysis of non-edible vegetable oil.
• RP-HPLC was used to monitor the progress of reaction during the base catalyzed ethanolysis.
• Individual calibration curves were found for quantitative analysis of ethyl esters at UV detection 215 nm.

Ultrasonication used for the ethanolysis of non-edible vegetable oil using KOH as a catalyst makes the process fully economic at molar ratio oil to ethanol 1:4, catalyst concentration 0.75 wt% of oil, reaction time 7–8 min, ultrasonic amplitude 50% (100 W/m3) and cycle 0.7 s. ultrasonication reduces the reaction time comparing to the conventional batch process. RP-HPLC was used to monitor the reactivity during the base catalyzed ethanolysis of Jatropha curcas oil. A RP-HPLC method has been developed for the determination of triacylglycerol, diacylglycerol, monoacylglycerol as well as free fatty acids and their corresponding ethyl esters. The determination of these components was carried out using a 40 min combined linear gradient with aqueous-organic and non-aqueous mobile phase steps: 90% methanol + 10% water in 10 min, 100% methanol in 0 min, 60% methanol + 15% n-hexane + 25% propan-2-ol in 30 min and 90% methanol + 10% water for last 10 min was used for fast monitoring of transesterification reaction. Individual calibration curves (relative peak area versus amount of the compound) were found for quantitative analysis of ethyl esters and acylglycerol shows good linearity at UV detection 215 nm. The identification of each compound can be done by APCI-MS in the position ion mode.