Patent ID: 6855653

Claim:
A process for preparing a hydrotreating catalyst composition comprising a composite carrier having an alumina part and a zeolite part wherein active metal belonging to group VIB of the periodic table and active metal belonging to Group VIII of the periodic table, each having a particle size less than about 50 Å are being preferentially supported on the alumina part of the composite carrier, and useful for desulfurization of gas oils, said process comprising the steps of: (a) impregnating a chelated metal solution containing at least one group VIB and at least one group VIII metal on to an alumina support, optionally in presence of a complexing agent; (b) flash drying the metal impregnated alumina support of step (a); (c) ball milling the flash dried metal-impregnated alumina support of step (b); (d) mixing the ball-milled metal-impregnated alumina support of step (c) with USY zeolite; (e) ball milling the mixture of step (d); (f) adding to the ball milled mixture of step (e) a phosphorous source; (g) aging the mixture of step (f) for a time period ranging between about 1 to 5 hours, and (h) molding, drying and calcining the mixture of step (g) to obtain the hydrotreating catalyst composition.