Theoretical Study of Peroxo- and Diperoxomolybdate Formation as Catalysts in the Oxidative Desulfurization of Diesel

The desulfurization is a very important process in the fuel production with less sulfur content, for this reason, several catalysts in different supports and conditions have been tested, however in the most of cases the reaction mechanism is not studied because it is very complicated. In the present work, the molybdate catalyst formation is studied by Density Functional Theory to demonstrate that this catalyst could be used in the oxidative desulfurization. As it is well-know, the solvent influence is very important in the reaction mechanism studies. There are several methodologies where the solvent effect could be considered. In this study the solvent was simulated by three ways: the first one by explicit n -water molecules (with n = 0, 1 and 2), the second one by PCM theory and the last by a combination of the two first. The results show that the structure called I01 is the most probable catalyst in the oxidative desulfurization reaction; additionally the effect of the water molecule surrounding this structure is fundamental to stabilize it. Finally this reactive structure could be formed in water and acetonitrile phases.