Catalyst used in fluid catalytic cracking (FCC) unit as a support of NiMoP catalyst for light cycle oil hydroprocessing

Abstract

The behavior of the NiMoP catalysts prepared by means of impregnation of different supports (MCM-41, SBA-15, catalyst used in FCC unit) has been studied, using them in the hydroprocessing of Light Cycle Oil (LCO) with the aim of maximizing the sulfur removal and reduce polyaromatics content; so the hydroprocessed LCO can be hydrocracked in another unit with metal noble catalysts.Catalysts have been characterized through several techniques: N2 adsorption–desorption, elemental analysis (ICP-AES), X-ray diffraction (XRD), acidity measurement by temperature programmed desorption (TPD) of tert-butylamine, temperature programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), UV–Vis spectroscopy, transmission electron microscopy (TEM), and temperature programmed oxidation (TPO) (spent catalysts). The hydroprocessing runs have been carried out in a fixed bed reactor working in trickle bed regime at 320–400 °C; 80 bar; H2:LCO ratio, 1000mLNH2mL−1LCO; space time, 0.2 h, and time on stream (TOS), 8 h.The catalyst NiMoP/HY-Al2O3 (spent FCC catalyst) stands out due to its high hydrodesulfurization activity attributable to the ease of impregnation of metals over FCC catalyst and the accessibility of the components of the LCO to the hierarchical porous structure. Its activity for reducing polyaromatics compounds of LCO is also remarkable, without diminishing the diesel fraction content by overcracking. Besides, the deposition of coke over this catalyst is scarce, since the retention of the high molecular weight molecules of LCO in its porous structure is minimized.