Effect of Ultrasound on Biodiesel Synthesis from Plant Oil

Abstract

The recent studies have clearly shown that the continuous exploitation of fossil fuels has adverse effects on the environment, while reserves of oils are sufficient for about next fifty years. As the need for energy rises, so do the energy policies tend to develop and research the renewable energy sources including biodiesel. The goal of this research is to examine the ultrasound effect on biodiesel synthesis process and to optimize synthesis conditions, examining the effect of several parameters in production process and biodiesel quality. Biodiesel synthesis was processed out of unused sunflower oil and sunflower oil used in fast-food (waist oil). Particularly, the ultrasound effect on production process-transesterification reaction was examined. After synthesis, examination of density, viscosity, flash point and yield were done using suitable apparatus and methods. The study results proved that the most optimal temperature with the use of ultrasound is 60°C, sonication time of 15 minutes and alcohol-oil molar ratio 3:1. Also, the results proved that using ultrasound during biodiesel synthesis, transesterification reaction can be processed on lower temperatures and still, biodiesel of good quality can be produced, contrary to conventional synthesis. Using the ultrasound generator for laboratory biodiesel synthesis largely shortens reaction time, increases rate of chemical reaction, decreases by-product amount, decreases alcohol amount, decreases waste water and, in the end, saves energy because the reaction is faster and takes less time at lower temperatures.