Estudio DFT del mecanismo de reacción de la esterificación de ácido levulínico con metanol catalizada por la zeolita H-Beta

Abstract

The esterification of levulinic acid to levulinate esters by heterogeneous acid catalysis is a promising chemical route for the sustainable production of high value-added products. In this work, a DFT study of the mechanism for this reaction was carried out using H-Beta zeolite as catalyst. The elementary steps of the reaction, such as acid adsorption and alcohol coadsorption, were identified and the associated transition states and intermediates were determined. The energy profile throughout the reaction was obtained and the energies associated with each step were found. Theoretical calculations revealed stable structures and a viable pathway for the formation of levulinate ester, where the rate-determining step is the formation of a tetrahedral intermediate via a TS involving hydrogen transfer from methanol to levulinic acid.