Heterogeneous oil transesterification in a single-phase liquid mixture using a co-solvent for improved biofuels production

CaO is an effective catalyst for the transesterification of vegetable oil with methanol, but reaction rates are lower than with homogeneous catalysts. Triglycerides are poorly miscible in methanol. To decrease the mass transfer resistance, we introduce a co-solvent to form a single phase solution. The most effective solvents are tetrahydrofuran, ethyl acetate, chloroform, and dichloromethane. Using these, the reaction rates are superior to the homogeneous catalyst. Both fatty acid methyl ester (FAME) yields and reaction rates were lower for n-heptane and acetone.