Biodiesel Production Process from Waste Vegetable Oil and Optimization of its Physical Properties

Biodiesel is Alkyl Ester of fatty Acids that is produced from vegetable oils or animal fats. Biodiesel compared with diesel fuel contains less sulfur and aromatic compounds, and includes 10% oxygen in its molecular construction which results decreasing in exhaust emission pollutants of diesel engine. In this research biodiesel is produced from waste cooking oil by means of Trans Esterification method in the presence of NaOH catalyzes (0.5 % oil weight) and 6:1 of methanol to oil ratio. For improving some physical properties of biodiesel, such as cloud point and pour point crystallization of ester with n-hexane solvent was used. Some blends with different levels of biodiesel and diesel fuel were obtained from each kind of blend fuel. Physical properties identified and compared to diesel fuel #2. Conclusions show: increasing of biodiesel percent in blend resulted increasing of density and viscosity. High percent of biodiesel in blends, has negative effect on cloud point and pour point, and so compared with diesel fuel, causes increasing these two properties.