Production of clean distillate fuels from heavy cycle oils

摘要

This invention discloses an enhanced process for the hydroprocessing of a feed, the feed comprising a highly aromatic refinery distillate stream boiling in the range between 300 DEG and 900 DEG F. The feed is separated into light and heavy streams such that the light stream contains from 0.1 to 5 wt. % dibenzothiophene, substituted dibenzothiophenes, and heavier polycyclic thiophenes. The lighter stream is hydrotreated at pressures from 300 DEG to 1000 DEG F. with a commercial catalyst having a hydrogenation component. The heavier stream is treated in the presence of hydrogen at higher pressure, from 600 to 2000 psig with a catalyst comprising active material having a Constraint Index of less than 2 in addition to a hydrogenation component in order to achieve over 35% conversion of material boiling above 630 DEG F. The active material of the catalyst is a highly siliceous zeolite or an acidic amorphous silica-alumina material.