FUEL 16 |
| Different types of MoS2/Al2O3 and NiMoS/Al2O3 catalysts were prepared by systematically using sonochemical synthesis and chemical vapor deposition (CVD) methods, and the performance of the prepared catalysts in the hydrodesulfurization (HDS) of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) was compared with that of catalysts prepared by an impregnation method. MoS2/Al2O3 prepared by a sonochemical method showed a higher HDS activity, particularly for the hydrogenation (HYD) route of the HDS, than one prepared by impregnation because MoS2 crystallites were highly dispersed on Al2O3 in the former catalyst. The activity improvement was greater for the HDS of DBT than for the HDS of 4,6-DMDBT. Ni selectively added to the MoS2 surface by CVD promoted the HDS activity, particularly for the direct-desulfurization (DDS) route of the reaction, to greater extents than one added by impregnation because the former method allowed an intimate interaction between added Ni and the MoS2 surface, as confirmed by the XPS analysis of the catalysts. NiMoS/Al2O3 prepared by combining two methods, sonochemical and CVD, showed a modest improvement in the activity over the catalyst prepared by impregnation, but the HYD activity of the former catalyst was significantly higher than that of the latter. |
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Green Chemistry for Fuel Synthesis and Processing
8:45 AM-12:10 PM, Sunday, 10 September 2006 Palace -- California Parlor, Oral
Division of Fuel Chemistry |