The application of the reactive distillation technique for the production of biodiesel via enzymatic alcoholysis (transesterification) of sunflower oil with ethanol in supercritical CO₂, which generates glycerol and a mixture of ethyl esters (biodiesel), was investigated. Kinetic parameters for the overall reaction were fit to experimental data [Madras et al. (Fuel 83, 2004, 2029-2033)] according to empirical and reversible reaction models. A fed-batch reactor was modeled with and without distillation approach. The results suggested that it is not attractive to apply reactive distillation to this reaction under the specified conditions since the products formed in this reaction are not volatile enough to be distilled off and dislocate the equilibrium toward the desired products. Moreover, the characteristics of the compounds involved, such as high viscosity, offer additional mass and heat transfer problems and may preclude the use of this technique for practical purposes.
 

Keywords : biodiesel, enzymatic alcoholysis, reactive distillation, sunflower oil