Hydrodesulfurization of oil utilizing a narrow pore size distribution catalyst

In a process for hydrodesulfurizing a sulfur and asphaltene-containing hydrocarbon oil which comprises contacting said oil under hydrodesulfurization conditions with hydrogen and a catalyst comprising an alumina support composited with a hydrogenation component, said hydrogenation component comprising at least one Group VIB metal component selected from the group consisting of at least one elemental metal, metal oxide or metal sulfide of a Group VIB element of the Periodic Table of Elements and at least one Group VIII metal component selected from the group consisting of at least one elemental metal, metal oxide or metal sulfide of a Group VIII metal of the Periodic Table of Elements, the improvement which comprises said catalyst having a median pore radius ranging from about 70 to about 95 Angstroms, a total pore volume between 0.45 and 1.50 ml/g;

• less than 0.05 ml/g of said pore volume being in pores with radii greater than 100 Angstroms;
• at least 0.40 ml/g of said pore volume being in pores with radii in the range between said median pore radius to about 10 Angstroms above and 10 Angstroms below said median pore radius;
• at least 75 percent of said pore volume being in pores with radii in the range between said median pore radius to about 10 Angstroms above and 10 Angstroms below said median pore radius;
• less than 0.05 ml/g of said pore volume being in pores with radii below 60 Angstroms, and a total surface area ranging between 130 and 500 square meters per gram.