TPR-S analysis of the catalytic behavior of Ru/Al2O3 catalysts in industrial conditions

The catalytic behavior of a Ru (5%)/Al2O3 catalyst was studied in the straight run gas oil/ light cyclic oil (SRGO/LCO) hydrotreatment at industrial conditions. Prior to the catalytic tests, the extrudates were sulfided at high pressure (P = 55 mPa), at two different sulfidation temperatures (503 and 573 K), with four different sulfiding mixtures (CH3)2S2–naphta–N2, (CH3)2S2–naphta–H2, CS2–naphta–N2 and CS2–naphta–H2. For comparison purposes, the Ru (5%)/Al2O3 catalyst was also sulfided using H2S (6 vol%)/N2 (P = 11 MPa). Complementary atmospheric pressure thiophene HDS experiments were also conducted. TPR-S experiments of the catalyst sulfided at industrial conditions and at atmospheric pressure were performed and correlated to the catalytic behavior. The results showed differences of 60% in HDS catalytic activity as a function of the sulfidation conditions used to activate the catalyst. The characterization suggests that the activity differences are associated with the stability of the RuS2 phase in reaction conditions.