Evaluation of Biodiesel Production Process by the Determining of the Total Glycerol Content in Biodiesel

Total glycerol content is one of the most important properties among the various properties of biodiesel. It has a close relationship with ester content because both are related to the remaining amount of intermediate compounds (mono- and di-glycerides) as well as the unconverted triglycerides. The total glycerol content increases then the ester content in biodiesel decreases. In this study, the efficiency of the biodiesel production process via the total glycerol content derived from transesterification refined palm oil (RPO) by methanol in the presence of sodium methoxide as a homogeneous base catalyst is estimated. The effects of experimental variables; including methanol/refined palm oil molar ratio (3:1-9:1 by mole), catalyst content (0.50-1.30 wt.% CH3ONa to RPO), reaction temperature (45-65°C) and reaction time (30-70 min) on the total glycerol content in biodiesel were investigated. A mathematical model was established a correlation based on response surface methodology. It was concluded that the molar ratio and catalyst content are the two most important factors affect the total glycerol content in biodiesel as well as the efficiency of the biodiesel production process.