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.