Kinetics of layered double hydroxide catalyzed esterification of fatty acids with glycerol

Abstract

This work reports experimental kinetic data and mathematical modeling on the esterification of oleic acid with glycerol using a layered double hydroxide (LDH) of a complex MgAlCO3 as catalyst. The results showed that the temperature and the oleic acid to glycerol molar ratio have major and significant effects on the glycerol conversion. Reactions performed at 180 °C led to higher total glycerol conversion (almost 99 % after 180 min) with higher selectivity of products following this order: monoolein, diolein and triolein. However, under these conditions, the products showed darker color when compared to products obtained at 160 °C with 90 % of glycerol conversion. MgAlCO3 catalyzed the esterification reaction between oleic acid and glycerol and led to an almost complete conversion of glycerol in a relatively short reaction time (up 2–3 h). Additionally, a simplified kinetic modeling approach based on the reaction stoichiometry was employed to describe the experimental data. This kinetic model was able to correlate well the experimental data of LDH-catalyzed kinetics of fatty acids esterification with glycerol, allowing a better understanding of the reaction kinetics.