Biodiesel production via peanut oil extraction using diesel-based reverse-micellar microemulsions

Vegetable oils have been studied as a feasible substitute for diesel fuel, and short term tests using neat vegetable oils have shown results comparable to those of diesel fuel. However, engine problems arise due to the high oil viscosity after long-term usage. Vegetable oil/diesel blending as biodiesel fuel has been shown to be one technique to reduce vegetable oil viscosity. The goal of this research is to demonstrate the feasibility of producing this biodiesel fuel via vegetable oil extraction using diesel-based reverse-micellar microemulsions as an extraction solvent. In this extraction technique, peanut oil is directly extracted into the oil phase of the microemulsion based on the “likes dissolve likes” principle and the product of the extraction process is peanut oil/diesel blend. The results show that diesel-based reverse micellar extract oil from peanuts more effectively than both diesel and hexane alone under the same extraction condition. An extraction efficiency of 95% was achieved at room temperature and short extraction time of 10 min in just a single extraction step. The extracted peanut oil/diesel blend was tested for peanut oil fraction, viscosity, cloud point and pour point, which all meet the requirements for biodiesel fuel.