Theoretical study of the oxidative desulfurization reaction in sulfur compounds present in crude oil

Oxidative desulfurization (ODS) has emerged as a highly promising and effective complementary technique to hydrodesulfurization for reducing sulfur content in fossil fuels. Notably, ODS demonstrates superior efficacy in removing challenging sulfur compounds (SCs) such as 4-methyldibenzothiophene and 4,6-dimethyldibenzothiophene. Therefore, it is imperative to unveil the molecular mechanisms underlying the ODS process and comprehend the reactivity properties of the participating species, offering insights to explain the mechanisms implicated. In this study, a thorough analysis of the reaction coordinate associated with the ODS process for a specific set of SCs was undertaken. The approach involved utilizing the Density Functional Theory and comparing the results with prior experimental observations to ensure the relevance of the findings in this study. In addition, reactivity trends were rationalized by applying temperature-dependent chemical reactivity theory. In this way, these results contribute to understanding the ODS process, which is essential to an environmentally friendly fuel production.