ABSTRACT
New environmental laws will require the gasoline composition to change dramatically in order to reduce automotive emissions. Auto/Oil studies have indicated that reducing sulfur will lower the emissions of hydrocarbons, NOx, and CO. Since a large portion of the sulfur in the gasoline pool comes from the FCC naphtha, reducing the FCC naphtha sulfur level will lower the sulfur level in the gasoline pool. Hydrotreating the feedstock to the FCC is an effective means of lowering FCC naphtha sulfur. Pilot unit experiments using hydrotreated feeds from Arabian and Alaskan North Slope crudes have shown that the sulfur level in the DB naphtha is reduced dramatically depending on the hydrotreating severity. Cutting the heavy naphtha endpoint will also help lower the sulfur level.
