Mathematical Modelling of Diesel Fuel Hydrodesulfurization Kinetics

The experimental data for hydrogenation of sulfur compounds including benzothiophenes (BT) and dibenzothiophenes (DBT) in the diesel fuel with 1.4 mass% of sulfur content is obtained using the laboratory setup with the aluminum-cobalt-molybdenum catalyst GKD-202 at the pressure of 3.5 MPa and different temperatures. The sulfur compound removal factor reaches 98 mass%. Dynamics of DBT and BT concentrations allowed designing a kinetic model represented by the system of differential equations of individual sulfur compound rates. The kinetic model was included in the developed software. The basis of the algorithm for reverse kinetic problem solution is the method of scanning through predefined range of constants. This enables performing the calculation with an error not exceeding 0.007%. The obtained data confirmed that chemical activity increases in the order: DBT, BT, sulfides. The rate of desulfurization decreases with increase in alkyl substituents concentrations. DBT desulfurization is much worse than the one of BT. The calculated data allowed building the graphs representing BT and DBT concentration dynamics.