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

The activities of hydrodesulfurization (HDS) and hydrogenation(HDS) fo r UFP-Al2O3 catalysts prepared by two methods, impregnation and superc ritical fluid drying process, were determined in a continuous flow mic roreactor, It is shown that the catalytic properties and the dispersio n of Mo species on alumina surface are greatly affected by the prepara tion method, as compared to that of ordinary Mo/Al2O3(prepared by impr egnating 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 whi ch bulk Mo/O-3 phase emerge for UFP-Mo/Al2O3 is considerably higher th an that for ordinary Mo/Al2O3 catalysts, implying that using UFP-Al2O3 and supercritical fluid drying process favor the dispersion of Mo spe cies onto the surface of alumina.