Lipase-Catalyzed Transesterification for Biodiesel Production in Ionic Liquid [Emim]Tfo

Abstract

Biodiesel production from waste cooking oil (WCO) was investigated using a mixture lipases of Novozym 435 and lipozyme TLIM as biocatalysts in ionic liquid 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([Emim]TfO). ¹H-NMR spectroscopy was conducted to quantify the biodiesel yield. The mixture lipases in [Emim]TfO were very efficient with the biodiesel yield of approximately 99%. Temporal dynamics studies indicated that the mixture lipases showed a positive synergistic effect and eliminated the rate-limiting step in biodiesel production. The mixture lipases showed the highest catalytic activity in [Emim]TfO in comparison with solvent-free, tert-butanol, and isooctane media. It was revealed that the mixture lipases in [Emim]TfO was an outstanding catalytic system for biodiesel production.

Keywords:

• Biodiesel
• Ionic liquids [Emim]TfO
• Enzymatic transesterification
• Waste cooking oil (WCO)
• ¹H-NMR

ACKNOWLEDGMENTS

The authors are deeply indebted to the Analytical and Testing Center of Huazhong University of Science and Technology for NMR analysis, and the financial support from 863 Program (2009AA03Z232), Doctoral Education Fund for New Teachers (20090142120090), Natural Science Foundation of Hubei Province (2008CDB359), and National Natural Science Foundation of China (31070709, 31270858).

Notes

*Equal contributor.