Transesterification Kinetics of Waste Vegetable Oil in Supercritical Alcohols

Abstract

The kinetic analysis method using the non-isothermal technique was proposed to determine the kinetic parameters for the transesterification reaction of waste vegetable oil (WVO) in supercritical alcohols. To investigate the transesterification of WVO, experiments have been carried out with WVO and alcohols at three molar ratios of 1:6, 1:12 and 1:18 for both supercritical ethanol (SCE) and supercritical methanol (SCM) at temperatures between 210 °C and 350 °C in a 25 mL batch reactor. The products were analyzed by gas chromatography mass spectrometry (GC-MS). To verify the effectiveness of the proposed kinetic analysis method, the experimental values were compared with the values calculated using the kinetic parameters obtained from this work. It was found that the proposed kinetic analysis method gave reliable kinetic parameters for the transesterification of WVO in supercritical alcohols. It was also seen that SCM was a better solvent than SCE for the transesterification of WVO.

Keywords

• non-isothermal
• transesterification reaction
• supercritical alcohols
• kinetic analysis