Density functional theory calculations are performed to investigate the hydrodesulfurization (HDS) mechanisms of different sulfur-containing compounds, such as thiophene, benzothiophene, dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) on the brim and CUS sites. Based on the systematic calculations, the dominant reaction pathway of different molecules are explored, and the structure-activity relationship of brim and CUS sites is mainly discussed under the real reaction conditions (p(H₂) = 4 MPa, T = 650 K). According to the DFT calculation results, brim site is more favorable for the HDS reactions of thiophene and benzothiophene. However, both brim and CUS sites are considered to participate in the DBT and 4.6-DMDBT HDS processes. The brim site provides the hydrogenation active sites, and the CUS site promotes the removal of sulfur atoms. The proposed mechanism strongly supports that the brim and CUS sites act in synergistic effect for the HDS reaction of the highly refractory organic sulfides.

进行密度泛函理论计算，以研究在帽沿和CUS位置上不同的含硫化合物（例如噻吩，苯并噻吩，二苯并噻吩（DBT）和4,6-二甲基二苯并噻吩（4,6-DMDBT））的加氢脱硫（HDS）机理。在系统计算的基础上，探索了不同分子的主导反应途径，主要讨论了在实际反应条件下（p（H ₂）= 4 MPa，T = 650 K）。根据DFT计算结果，边缘部位更有利于噻吩和苯并噻吩的HDS反应。但是，边缘和CUS站点都被认为参与了DBT和4.6-DMDBT HDS流程。边缘位点提供了氢化活性位点，而CUS位点则促进了硫原子的去除。所提出的机制有力地支持了边缘和CUS位点在高难降解有机硫化物的HDS反应中起协同作用。