Gasoline and reformate upgrading process

Abstract

A low sulfur gasoline of relatively high octane number is produced from a catalytically cracked, sulfur-containing naphtha by hydrodesulfurization followed by octane enhancing treatment in a fluidized bed catalytic process, in the presence of an aromatics-rich feedstream. The process converts the hydrodesulfurized intermediate and the aromatics-rich feedstream to a gasoline boiling range fraction of high octane number. The fluidized bed catalytic process is carried out over zeolite catalyst particles in a turbulent reactor bed at a temperature of about 600.degree. to 800.degree. F. (316.degree. to 427.degree. C.) and pressure of about 100 to 250 psig (790 to 825 kPa. The catalyst has an apparent particle density of about 0.9 to 1.6 g/cm.sup.3 and a size range of about 1 to 150 microns, and average catalyst particle size of about 20 to 100 microns containing about 10 to 25 weight percent of fine particles having a particle size less than 32 microns. The feed vapor is passed upwardly through the fluidized catalyst bed under turbulent flow conditions; turbulent fluidized bed conditions are maintained through the reactor bed between transition velocity and transport velocity at a superficial fluid velocity of about 0.3 to 2 meters per second. Treatment in the fluidized bed catalytic process 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.