The effect of carrier in KCoMoS-supported catalysts for hydro-upgrading of model FCC gasoline

Abstract

K-CoMo/Sup (where Sup = Al2O3, SiO2, TiO2 and ZrO2) catalysts were synthesized using H3PMo12O40, CoCO3, KOH and citric acid. The catalysts were characterized by temperature-programmed reduction (TPR), temperature-programmed desorption of NH3, X-ray photoelectron spectroscopy, transmission electron microscopy. Samples were tested in hydrotreating of model fluid catalytic cracking gasoline and in selective hydrogenation of 1,5-hexadiene and n-heptene-1. The type of used carrier significantly affected the morphology of active phase and catalytic properties. Active sites productivity of K-CoMo/Sup catalysts in hydrodesulfurization (HDS) and olefin hydrogenation (HYDO) reactions as well as HDS/HYDO selectivity correlated with active phase morphology excepting TiO2-supported sample. Productivity of active sites in reactions of selective hydrogenation of diolefin depended on maximum peak reduction obtained from TPR, which in turn was a function of acidity of using supports. The highest HDS/HYDO selectivity was obtained at catalyst which possessed the lowest selectivity towards partial hydrogenation of diolefine compared to complete hydrogenation.