Applied Catalysis A: General, Vol.352, No.1-2, 124-132, 2009
Activity and stability studies of MoO2 catalyst for the partial oxidation of gasoline
The present investigation is focused on the performance of molybdenum dioxide (MoO2) as a catalyst for the partial oxidation of isooctane. Metallic character and high oxygen mobility exhibited by this oxide appear to enhance its catalytic activity, which can be explained in terms of the Mars-van Krevelen mechanism. An oxygen-to-carbon ratio (O/C of 0.72 seems to stabilize the catalytic performance, which could reach H-2 yields of 78% and carbon conversions of 100%, at 700 degrees C and 1 atm, after 20 h on stream. In addition, the catalyst was tested for sulfur tolerance using thiophene as model sulfur compound. Our findings indicate that the catalytic activity is barely affected even at sulfur concentrations as large as 500 ppm, after 7 h on stream. Finally, the catalyst performance was compared to that of a nickel catalyst using premium gasoline as fuel. MoO2 displayed a stable performance whereas the Ni catalyst deactivated due to coke formation. (C) 2008 Elsevier B.V. All rights reserved.