Optimization of cold flow properties of biodiesel by addition of cold flow improver

Abstract

Despite the renewable and sustainable characteristics, biodiesel is poor in cold flow property (CFP) which causes a significant drawback that have limited its application. Thickening or crystallization of biodiesel in low temperature can readily result in the clogging of fuel pipes and fuel filters. The purpose of this study is to determine the optimum properties of blended biodiesel that gives the most accurate simulation results of blended biodiesel’s CFP. TmoleX18 and COSMOthermX were used to identify the viscosities and densities of pure palm oil biodiesel and pure ethanol under different temperatures. The densities, viscosities and pour points of ethanol blended biodiesel was then calculated by using Grunberg-Nissan and, Riazi and Daubert equations. The simulation results were obtained under different compositions of ethanol added from 0 to 0.2 mole fraction at temperature range of 30 °C to -5 °C. The optimum combination of viscosities and densities of blended biodiesel for the blended cold flow properties was at 10 °C and 30 °C respectively. The simulation error at 0.1 mole fraction of ethanol was 0.92 %.