abstract |
Low sulfur gasoline of relatively high octane number is produced from a catalytically cracked, sulfur-containing naphtha by hydrodesulfurization followed by treatment over an acidic catalyst system comprising a zeolite having the topology of ZSM-5 and a zeolite sorbing 10 to 40 mg 3-methylpentane at 90 DEG C., 90 torr, per gram dry zeolite in the hydrogen form, e.g., ZSM-22, ZSM-23, or ZSM-35. The treatment over the acidic catalyst system in the second step restores the octane loss which takes place as a result of the hydrogenative treatment and results in a low sulfur gasoline product with an octane number comparable to that of the feed naphtha. |