Kinetic Studies of Hydrodesulphurization of Dibenzothiophen on a Ni2P/MCM-41 Catalyst

Abstract

The MCM-41 supported nickel phosphide catalyst was successfully prepared by impregnation of nickel phosphate precursors with MCM-41 support, followed by reduction of the precursors in hydrogen at 923 K. The as prepared Ni₂P/MCM-41 catalyst was characterized by X-ray diffraction (XRD) and N₂-adsorption specific surface area measurements (BET). The effects of reaction temperature, pressure, weight hourly space velocity (WHSV) and hydrogen to oil volume ratio (H₂/Oil) on DBT HDS performance over Ni₂P/MCM-41 were investigated with the model gasoline containing DBT. Finely, the kinetics for the DBT HDS over Ni₂P/ MCM-41 catalyst was studied. The results showed that the active phase formed over Ni₂P/M CM-41 catalyst was mainly Ni₂P. The DBT conversion increased with increasing the reaction temperature, pressure, and H₂/Oil ratio. However, increasing the WHSV would lead to a decrease in DBT conversion over Ni₂P/ MCM-41 catalyst. A Langmuir–Hinshelwood model was used to analyze the kinetic data and to derive activation energy. In addition, take the effects of the pressure of H₂ and H₂/oil ratio into account, the modified kinetic model is also proposed: 1/(1–x)–1 = 10086.97e^120.72RTp^2.534_H (H₂/Oil)^2.471WHSV^–1.217.