ULTRAFINE MO/AL2O3 CATALYSTS FOR HYDRODESULFURIZATION .1. CATALYTIC PERFORMANCES AND REDUCTION BEHAVIOR OF UFP-MO/AL2O3 CATALYSTS

The activities of hydrodesulfurization (HDS) and hydrogenation(HDS) for UFP-Al2O3 catalysts prepared by two methods, impregnation and supercritical fluid drying process, were determined in a continuous flow microreactor, It is shown that the catalytic properties and the dispersion of Mo species on alumina surface are greatly affected by the preparation method, as compared to that of ordinary Mo/Al2O3(prepared by impregnating ordinary gamma-Al2O3 with molybdenum salt the HDS activities of UFP-Mo/Al2O3(prepared by impregnating UFP alumina with Mo salt) are considerably high under the same condition, So do the HYD activities, It is also indicated from TPR, LRS and XRD that the Mo loading at which bulk Mo/O-3 phase emerge for UFP-Mo/Al2O3 is considerably higher than that for ordinary Mo/Al2O3 catalysts, implying that using UFP-Al2O3 and supercritical fluid drying process favor the dispersion of Mo species onto the surface of alumina