Optimized conventional and ultrasound-assisted ethyl transesterification of jatropha (Jatropha curcas) and palm (Elaeis guineensis) oil mixtures

Abstract

While biodiesel from jatropha oil is oxidation-sensitive and fluid, palm oil-biodiesel is more stable, but with sub-optimal fluid dynamics. Mixing these oils before reaction could be advantageous for reducing steps in production while generating biodiesel with desired cold-flow and stability properties. Here, we performed central composite designs to optimize the transesterification of jatropha and palm oil mixtures via conventional alkaline (CT) and ultrasound-assisted transesterification (UT), assessing the physicochemical properties of the biodiesel. Acid esterification of oil mixtures was followed by transesterification with NaOH and ethanol. The two-step conversion of jatropha and palm oil binary mixtures was successful. UT resulted in 93%-time reduction (4 min) in comparison to CT (60 min). The increased presence of jatropha oil improved the fluid dynamics of biodiesel. UT is a promising technology for synthesizing biodiesel in less time. The transesterification of binary mixtures is a direct and simple approach for reducing steps in biodiesel production.

Keywords:

• Biodiesel
• central composite design
• fluid dynamics
• two-step transesterification

Disclosure statement

The authors declare that there are no conflicts of interest.

Acknowledgments

Authors would like to thank the research team of the Laboratory of Oils and Fats led by Prof. Marisa Regitano-d’Arce. The first author would like to thank the Peruvian companies Verdal R.S.M. Peru S.A.C. and Industrias de Palma Aceitera de Loreto y San Martín S.A. - INDUPALSA, for donating jatropha and palm oils, and Instituto de Investigación Agraria - INIA San Martín/Perú, for donating jatropha oil.

Additional information

Funding

This study was financially supported by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brazil/CAPES under Finance Code 001; FAPESP under Grants n° 2017/02819-8 and 2013/23469-4; PEC-PG (Programa de Estudantes – Convênio de Pós-Graduação) – Brazil/CAPES under grant n° 12513130; Universidad Nacional de San Martín under resolution n° 134-2014-UNSM/CU-R of 2014.