Aerobic Oxidation Desulfurization of Dibenzothiophene Derivatives in Diesel Oil: Role of Electron-Rich Sites in Bimetallic Catalysts

Abstract

The difficulty in removing dibenzothiophene derivatives from diesel, especially 4,6-dimethyldibenzothiophene (4,6-DMDBT), remains a huge obstacle to achieving efficient and clean desulfurization of oil products. However, the construction of a catalyst with efficient activation and utilization of O₂ for the oxidation of sulfur-containing substrates remains a major challenge for the industrial application of aerobic oxidative desulfurization (AODS). In this article, we manipulate the electronic structure and surface acid–base environment of the MoO_x catalyst by introducing Ta atoms with low electronegativity and constructing bimetallic catalysts to promote the generation of more electron-rich active sites. The optimal MoTa-2 catalyst realizes a 100% sulfur removal rate within 5 h for 4,6-DMDBT and displays amazing cycling stability across 26 cycles, surpassing the performance of known heterogeneous catalysts. This study extends a novel understanding of drawing support from electronic structure control strategies to enhance AODS ability.