Patent ID: 7297251

Claim:
A process for hydrodesulfurizing an olefinic naphtha boiling range feedstream and retaining a substantial amount of the olefins, which feedstream contains a substantial amount of organically bound sulfur and olefins, which process comprises: a) hydrodesulfurizing said feedstrearn in a first reaction zone operated at hydrodesulfurization conditions and in the presence of hydrogen and a first hydrodesulfurization catalyst consisting essentially of about 1 to about 30 wt. % of CoO, about 5 to about 50 wt. % of MoO 3, and a median pore diameter of about 60 Å to about 200 Å, said first reaction zone operated at hydrodesulfurizing conditions such that from about 20% to about 99% of the sulfur reduction of said feedstreanx occurs in this first reaction zone, thereby resulting in a partially desulfurized product stream; and b) hydrodesulfurizing the partially desutfurized product stream of stop a) above in a second reaction zone operated at hydrodesulfurizing conditions containing a second hydrodesulfurization catalyst consisting essentially of about 0.1 to about 27 wt. % of CoO, about 1 to about 45 wt. % of MoO 3, and a median pore diameter of about 60 Å to about 200 Å, said second hydrodesulfurization catalyst having a metals loading such that each metal is present in an amount of about 10 to about 95% less than the amount present on said first hydrodesulfurization catalyst and a median pore diameter equal to or greater than said first hydrodesulfurization catalyst.