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.

Technical review on flexible processing middle distillate for achieving maximum profit in China

“…As stated, the introduction of hydrogen into LCO fraction can enhance the cracking ability on acidic component [28]. In addition to the cracking behavior occurring in RLG/ FD2G/LCO-X technology, FCC unit can also convert lighter fraction via a carbenium mechanism.…”

Enhancing the Conversion of Polycyclic Aromatic Hydrocarbons from Naphthenic Heavy Oil: Novel Process Design, Comparative Techno-Economic Analysis, and Life Cycle Assessment

“…In the current refining industry, one of the most challenging problems is how to utilize LCO and heavy oil, which is rich in polycyclic aromatic hydrocarbons (PAHs) for deep processing with a high added value. Several processing pathways of PAH comprehensive utilization have been proposed, such as hydrotreating, − selective ring opening, , and hydrocracking. ,− However, the conversion of PAHs in LCO and heavy oil by aromatic saturation is quite limited in the hydrotreating process because of the high PAH content (with average of 70 wt % and even more than 90 wt %, especially high in naphthenic heavy oil) . Although the selective ring-opening process could transform LCO into clean diesel components with a high cetane number, high hydrogen and energy consumption combined with the declining market demand are the main reasons to limit its industrial applications.…”

“…9,16−19 However, the conversion of PAHs in LCO and heavy oil by aromatic saturation is quite limited in the hydrotreating process because of the high PAH content (with average of 70 wt % and even more than 90 wt %, especially high in naphthenic heavy oil). 20 Although the selective ring-opening process could transform LCO into clean diesel components with a high cetane number, high hydrogen and energy consumption combined with the declining market demand are the main reasons to limit its industrial applications. The hydrocracking process can produce basic petrochemical raw materials such as benzene, toluene, and xylenes (BTX), and be applied in the integrated units of oil-refining and chemical industries.…”

Efficient Conversion of Light Cycle Oil into Gasoline with a Combined Hydrogenation and Catalytic Cracking Process: Effect of Pre-distillation

“…It is worth noting that a 13.13 wt % content of tricyclic aromatic hydrocarbon was found, which is higher than that of the paper reported. 23 In this study, a kind of commercial Ni-Mo/Al 2 O 3 hydrogenation catalyst was applied in the process of hydrogenation of LCO and its properties are shown in Table 2. The catalyst used in the process of catalytic cracking was a commercial equilibrium FCC catalyst based on USY zeolite supplied by Kelaimai Refinery, which was specially designed for cracking macromolecule hydrocarbons, and its properties were obtained as presented in Table 2.…”