Response surface study and kinetic modelling of biodiesel synthesis catalyzed by zinc stearate

A kinetic study of the reaction was performed. Two models were proposed. Model 1 assumed a complete mixing of the dissolved catalyst with the reactants and a second-order mechanism for the forward and reverse reactions, where the reaction system could be described as pseudo-homogeneous and the catalyst was dissolved in the reaction medium. Model 2 supposed that the dissolved catalyst formed part of a macro emulsion, with mass transfer resistance in the boundary layer around the droplets. The kinetic constants were determined, and Model 2 showed a better fit to the experimental data. The model and the kinetic parameters allow to generate reaction operation strategies.