Naphthalene as a model molecule to explain the mechanism of hydrodesulfurization over Pd-Pt/γ-Al2O3 catalysts (original) (raw)

The development of the hydrodesulfurization (HDS) of dibenzothiophene (DBT) type molecules by the hydrogenation (HYD) route over Pd-Pt/γ-Al2O3 catalysts was studied through the analysis of the reactivity of naphthalene over these materials. A series of Pd-Pt/γ-Al2O3 catalysts with different Pd/(Pd+Pt) molar ratios were prepared by the coimpregnation method, characterized by atomic absorption and nitrogen adsorption-desorption techniques and tested at temperatures between 503 and 543K and 5MPa. Results show a synergy in the selectivity to trans-decaline. It was concluded that the reaction mechanism of naphthalene over Pd-Pt/γ-Al2O3 bimetallic catalysts entails the roll-over of the Δ1,9-octalina over the catalytic surface. In this way, there exists a similarity with the reaction mechanism of DBT by the HYD route of HDS.