(578e) Evaluation of the Solvent Polarity on Extraction of Castor Oil By Soxhlet Method

Conversion of castor oil into biodiesel can be an alternative technological to cover the current demand of biofuels, this vegetable oil feedstock does not challenge with the food industry and avoiding the use of the oil palm. Soxhlet extraction method was used to evaluate the polarity of three extracting solvents (hexane, diethyl ether and ethanol) on the oil extraction from castor oil seeds. A factorial design 2³ experiments were used to study the effect of the size particle (1.981, 2,80 and 3.35 mm) and extraction time (1, 2 and 3 h) on the oil yield for each extracting solvent employed. Peroxide value, iodine value, saponification value, acid value, refractive index, viscosity index and density were the physicochemical properties used to characterize the castor oil extracted. The analysis of these properties shows that oil is suitable for the production of biodiesel. The solvent polarity has a significant effect on the oil yield, indicating that a greater oil yield was obtained when the solvent polarity is lower. Hexane showed to be the best solvent for the castor oil extraction, in terms of high oil yield (48%). However, diethyl ether reached an oil yield of 45% under the same extraction conditions used for hexane, which had a particle size of 2.80 mm and an extraction time of 3 h. Based on oil yield, the castor oil seeds have a higher affinity by non-polar solvents.