Method for the production of very low sulfur diesel

Abstract

A process for the deep desulfurization of diesel range feedstock to produce low sulfur diesel fuels by contacting a sulfur containing diesel range feedstock with a cobalt molybdenum (CoMo) catalyst followed by a nickel containing catalyst, such as nickel molybdenum (NiMo), nickel tungsten (NiW), nickel tungsten molybdenum (NiWMo) and nickel cobalt molybdenum (NiCoMo), under a combination of elevated temperature and superatmospheric hydrogen pressure to convert the sulfur in the sulfur-containing feedstock to inorganic sulfur compounds and produce a desulfurized product having a sulfur content below SO ppm by weight. The process can include a dual catalyst system, wherein the sulfur containing diesel range feedstock is desulfurized with a cobalt molybdenum (CoMo) catalyst and then the sulfur compounds can optionally be stripped from the stream prior to contacting with the nickel containing catalyst. The preferred desulfurized product contains less than 11 wt. % polycyclicaromatics and has an increased cetane number.

Dependencies are inferred from the claim text.