Fluid Catalytic Cracking of Hydrogenated Light Cycle Oil for Maximum Gasoline Production: Effect of Catalyst Composition

Abstract

Selective hydrogenation and subsequent catalytic cracking of light cycle oil (LCO) from a fluid catalytic cracking unit is expected to produce more high-octane-number gasoline. In this process, the multi-ring aromatics are selectively hydrogenated and transformed to naphthenic aromatics, which are further converted into the gasoline fraction through cracking reaction. This work has systematically studied the effect of catalyst composition on the cracking performance of hydrogenated LCO (hydro-LCO). The results indicate that, the cracking activity of LCO was substantially improved after hydrogenation. In comparison to the ZSM-5-zeolite-based catalyst, both an efficient conversion of hydro-LCO to gasoline and a greatly enhanced hydrogen transfer reaction were obtained over the Y-zeolite-based catalyst, further resulting in a higher hydrogen utilization efficiency. In addition, the active acid sites for hydro-LCO cracking were inferred, and a possible reaction network was proposed.