Process for producing aromatics of high purity from oil cuts

Claim 1

A process for producing aromatic hydrocarbons from saturated or unsaturated gasolines, in the presence of hydrogen and a catalyst, in at least one reaction zone, each reaction zone being divided into successive steps (α) and (β) wherein step (α) is conducted at 400°-600° C. under a pressure of 1 to 60 kg/cm 2 , with a substantially neutral γ-alumina catalyst having a specific surface less than 100 m 2 /g, and step (β) is conducted at 500°-600° C. under a pressure of 1 to 60 kg/cm 2 , with an acidic catalyst, of cubic γ-alumina or chlorinated or fluorinated alumina each step being conducted at an hourly feed rate by volume of the liquid charge of about 0.1-10 times the volume of the catalyst, in the presence of a catalyst containing (a) alumina, (b) 0.01-5% by weight of platinum with respect to alumina, (c) 0.001-1% by weight with respect to alumina of at least one metal selected from the group consisting of rhodium and palladium, and (d) 0.0001-0.05% by weight with respect to alumina of at least one metal selected from the group consisting of copper, silver and gold.