LAUSR

The well-known kinetics of Fischer esterification has already been reported for various systems. Despite this fact, the kinetic model of esterification of oleic acid and methanol under catalysis with sulfuric acid is still debated in the literature. The main reason is the two-phase character of the reaction mixture being neglected in kinetic studies. Contrary to this, the kinetics of autocatalytic esterification of cyclic alcohols with formic acid have not been published so far. Here, we present a kinetic study of both systems to assess the influence of the non-ideal (multi-phase) behavior on kinetic modeling. For the system of autocatalytic esterification of cyclic alcohols, we have found that a simple kinetic model without activity coefficients provides a good description of the experimental data. However, the same model is insufficient for the system of oleic acid and methanol. Therefore, we have developed a new approach based on kinetic modeling, including activity coefficients. Consequently, we have been able to describe for the first time the kinetics of oleic acid esterification in a homogeneous reaction mixture. Moreover, we provide a novel explanation for the commonly observed inhibition of this reaction by water as a result of phase equilibria in the reaction mixture.