摘要：Graphical abstractDisplay OmittedHighlights•Firstly, glycerol adsorbs on Lewis acid and Brönsted basic sites of the perovskite.•Dihydroxyacetone is formed on the basic sites of the perovskite in the second stage.•Novel transformation of dihydroxyacetone to 2,3-enol on acid sites is reported.•The surface oxygen atoms show a dual behavior as Brönsted base/acid species.•Finally, desorbed 2,3-enol is transformed into hydroxyacetone by tautomerization.AbstractGlycerol is currently a co-product of biodiesel production, and it is well-known to be a platform molecule, which is widely used in etherification, dehydration, dehydrogenation, oxidation, and reforming reactions, to produce chemicals of high value for the chemical industry. In this study, we theoretically address the dehydration of glycerol over the SrTiO3-type perovskite. The study includes the characterization of the transition states and intermediates occurring along the reaction pathway, and a possible mechanism is proposed, as well. The results show that the dehydration of glycerol occurs via a four-stage mechanism corresponding to the adsorption of glycerol on the perovskite, the surface reaction to produce the adsorbed dihydroxyacetone, the elimination of water produce 2,3-enol, and finally the desorption of this enol, which in turn undergoes keto-enol tautomeric equilibrium to form hydroxyacetone (HA). The rate-limiting stage corresponds to the formation of 2,3-enol showing an activation barrier of 106.3 kcal/mol.
