| Hydrodenitrogenation of hetero-nitrogen compounds in petroleum crudes and in synthetic liquids derived from oil shale and coal is studied by using quinoline as a model nitrogen containing compound and benzene as a diluent. Both the external and internal mass transfer rates in the Ni-W Y-type zeolite have been calculated in order to determine the possibility of diffusion limitations. Kinetic data were taken from a continuous-flow Berty-type reactor at 34 to 72 bars, 350 to 460{dollar}spcirc{dollar}C, and hydrogen mol fraction from 25 to 90%. Hydrogenation of the solvent benzene is negligible unless the nitrogen reactant is highly denitrogenated. Catalyst deactivation and reactivation occurred during the experimental operations. A number of derivatives were found in the product as a result of the high hydrogenation ability of Ni-W Y-type zeolite. Saturation of aromatic heterocyclics approached reaction equilibria quickly at certain reaction conditions. A Langmuir-Hinshelwood model was used to account for kinetic behavior, and the Redlich-Kwong EOS was used to consider nonideal gas behavior. A prediction algorithm based on the simplification of the HDN network reproduced the experimental data well. Reaction in the presence of high concentration hydrogen sulfide inhibits hydrogenation and causes a slight decrease in the overall quinoline HDN reaction rate. In comparing HDN reaction rates between the Ni-W Y-type zeolite catalyst and the commercial HDS3A alumina type catalyst, the former one shows higher denitrogenation activity at high hydrogen partial pressure conditions. |
