Response Surface Methodology for Biodiesel Production Using Calcium Methoxide Catalyst Assisted with Tetrahydrofuran as Cosolvent

The present study was performed to optimize a heterogeneous calcium methoxide (ca(och3)2) catalyzed transesterification process assisted with tetrahydrofuran (thf) as a cosolvent for biodiesel production from waste cooking oil. response surface methodology (rsm) with a 5-level-4-factor central composite design was applied to investigate the effect of experimental factors on the percentage of fatty acid methyl ester (fame) conversion. a quadratic model with an analysis of variance obtained from the rsm is suggested for the prediction of fame conversion and reveals that 99.43% of the observed variation is explained by the model. the optimum conditions obtained from the rsm were 2.83 wt% of catalyst concentration,11.6: 1 methanol-to-oil molar ratio,100.14 min of reaction time,and 8.65% v/v of thf in methanol concentration. under these conditions,the properties of the produced biodiesel satisfied the standard requirement. thf as cosolvent successfully decreased the catalyst concentration,methanol-to-oil molar ratio,and reaction time when compared with biodiesel production without cosolvent. the results are encouraging for the application of ca(och3)2 assisted with thf as a cosolvent for environmentally friendly and sustainable biodiesel production. © 2017 nichaonn chumuang and vittaya punsuvon.