The catalytic performance of Mo supported on hierarchical alumina-silica (Si/Al=15) with Mo loadings of 3

6 and 15 wt% was investigated for the oxidative desulfurization (ODS) of model and real oil samples. Hierarchical alumina-silica (hAl-Si) was synthesized by economical and ecofriendly silicate-1 seed-induced route using cetyltrimethylammonium bromide (CTAB) as mesoporogen. The effect of CTAB on the structure of catalyst was studied by characterization techniques. The results revealed that 6%Mo/hAl-Si had the highest sulfur removal compared to the other catalyst loadings. The effect of operating parameters was evaluated using Box-Behnken experimental design. The optimal desulfurization conditions with the 6%Mo/hAl-Si catalyst were determined at oxidation temperature of 67℃

oxidation time of 42 min

H

2

O

2

/S molar ratio of 8 and catalyst dosage of 0.008 g·ml

-1

for achieving a conversion of 95%. Under optimal conditions

different sulfur-containing compounds with initial concentration of 1000 ppm

Dibenzothiophene (DBT)

Benzothiophene (BT) and Thiophen (Th)

showed the

catalytic oxidation reactivity in the order of DBT BT Th. According to the regeneration experiments

the 6%Mo/hAl-Si catalyst was reused 4 times with a little reduction in the performance. Also

the total sulfur content of gasoline and diesel after ODS process reached 156.6 and 4592.2 ppm

respectively.