Claus Brostrom Nielsen - Haldor Topsoe A/S
As sulfur regulations tighten, refiners find it increasingly difficult to meet specifications from their FCC gasoline post-treatment units. Particularly the octane number suffers because of the necessary sulfur removal.
Selective catalysts and feed manipulation can lessen the octane loss and the overall impact on the refinery economics. This paper will describe the levers available to the refinery to reduce the octane loss. We will also illustrate the comprehensive process model that Topsoe uses to calculate the octane loss for various feedstock and feed components. The model is a molecular based and sums up the octane impact on each molecule processed through the hydrotreating unit.
The presentation will also highlight a new process technology for gasoline post treatment to 10 wtppm product sulfur that will significantly reduce the octane loss. Topsoe licenses this process technology for grassroots units, but can revamp existing gasoline post treatment units to utilize this technology. The octane savings obtained is typically about 2/3 to 3/4 of the octane loss observed with today’s conventional process technology at the same product sulfur.