HDS of a model FCC gasoline over transition monometallic sulphide (TMS) catalysts

PETR 89

Antoine Daudin, antoine.daudin@etu.univ-poitiers.fr1, Sylvette Brunet, sylvette.brunet@univ-poitiers.fr1, Guy Pérot1, and Christophe Bouchy, christophe.bouchy@ifp;fr2. (1) UMR CNRS 6503 Catalyse en Chimie Organique University of Poitiers, 40 avenue du Recteur Pineau, poitiers, 86022, France, (2) Catalysis and Separation Division, IFP Lyon, BP 3, Vernaison, 69390, France
The selective HDS of FCC gasoline is a sensible option for reducing sulphur content in commercial gasoline. The conversion at 250°C under 20 bar of a model FCC gasoline (composed of 2 methylthiophene (2MT), 2,3 dimethylbut-2-ene (23DMDB2N) and orthoxylene in n-heptane) was studied over a serie of unsupported transition monometallic sulphides (TMS) (Ni3S2, PdS, Co9S8, Rh2S3, RuS2, PtS and MoS2). Volcano type relationships between the ab initio calculated metal-sulphur bond energies E(M-S) and the activity in the hydrodesulfurization of 2MT (HDS) on the one hand, and the hydrogenation of 23DMB2N (HYDO) on the other, were obtained. This is in accordance with what was reported in the literature regarding the HDS of dibenzothiophene and the hydrogenation of biphenyl. In both cases (HDS and HYDO), a maximum of activity was obtained with Rh2S3, which corresponds to a medium metal-sulphur bond energy E(M-S) of 125 kJ/mol. However, the best HDS/HYDO selectivity was obtained with Co9S8 and RuS2 with metal-sulphur bond energies of 109 kJ/mol and 140 kJ/mol respectively.