Kinetic study of effects of aromatic compounds on deep hydrodesulfurization of 4,6-dimethyldibenzothiophene

Diesel fuel and gas oil contain considerable amounts of aromatic and nitrogen compounds, which may affect the HDS reaction rate. The effects of aromatic compounds on HDS of 4,6-dimethyl-dibenzothiophene (DMDBT) were studied kinetically using a previously developed method. Two catalysts were used, i.e., Cr344(CoMo/Al₂O₃) and Cr424(NiMo/Al₂O₃). The presence of 1-methylnaphthalene (1-MN) and fluorene affected significantly on HDS of 4,6-DMDMBT at 300°C and 300 psi. The aromatic compounds had more negative impact on the hydrogenation pathway than on hydrogenolysis pathway. A comparison of the two aromatic compounds showed that fluorene was a stronger inhibitor than 1-MN.