The application of theoretical solutions to the differential mass balance equation for modeling of adsorptive desulfurization in a packed bed adsorber

Adsorptive removal of organosulfur compounds, lumped as total sulfur content, from a real diesel fuel was carried out in a packed bed adsorber. A novel approach was taken in the application of theoretical solutions to the differential mass balance equation using modern software tools, and one classic method as point of reference. Adsorptive desulfurization is a perspective downstream process to hydrodesulfurization for achieving sulfur concentration levels of less then 10 mg kg−1. Compared to the conventional hydrodesulfurization process, the deep desulfurization can be accomplished without changing the physical properties of the product and at relatively low temperature and pressure. The adsorber apparatus comprised computer control, enabling completely automated operation. Adsorbent was activated carbon SOLCARB C from Chemviron Carbon, Belgium. The experimental results regarding the influence of flow rate and bed depth on the outlet sulfur concentration were evaluated as well as the models ability to describe the adsorption kinetics and to estimate the breakthrough curves. Ultra deep desulfurization of diesel fuel was achieved and it was determined that outlet sulfur concentration was being lowered by decreasing flow rate and increasing bed depth. The closest fit to the experimental data was achieved for the Bohart-Adams model.