TWO-STEP METHOD OF SATURATION OF AROMATIC COMPOUNDS OF DIESEL FUEL, USING CATALYST BASED ON NON-PRECIOUS METAL Russian patent published in 2019 - IPC C10G45/50 C10G65/08 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of improving properties of distillate feedstock characterized by concentration of organic nitrogen, concentration of polyaromatic compounds and cetane index, where said method includes: introduction of said distillate feedstock into contact with first catalyst contained in first reaction zone, for hydrodenitrogenation of organic nitrogen-containing compounds and saturation of polyaromatic compounds, wherein in the distillate feedstock, the concentration of the nitrogen-organic compounds ranges from 100 ppm (wt.) to 3500 ppm (wt.), the sulfur concentration being in the range of about 0.1 wt. % up to about 3.5 wt. %, concentration of polyaromatic compounds is in range of 12 wt. % up to 50 wt. % concentration of monoaromatic compounds is in range from 1 wt. % up to 25 wt. %, and wherein said first reaction zone operates under conditions suitable for hydrodenitrogenation and saturation of polyaromatic compounds, and obtaining from said first reaction zone a treated waste product characterized by low concentration of organic nitrogen with respect to said concentration of organic nitrogen and reduced concentration of polyaromatic compounds with respect to said concentration of polyaromatic compounds; separating said treated effluent into a heavy fraction and a lighter fraction; introducing said heavy fraction into contact with a second catalyst contained in a second reaction zone for saturating monoaromatic compounds, wherein said second reaction zone operates under conditions suitable for saturating monoaromatic compounds, and wherein reaction pressure in second reaction zone is higher than reaction pressure in first reaction zone; and obtaining, from said second reaction zone of reactor product, said second catalyst comprising a base metal catalyst containing either a nickel component or a cobalt component, and either a molybdenum component or a tungsten component supported on an inorganic oxide support, and wherein said reactor product includes a distillate portion; supplying the distillate part to the stripping column for the product for producing diesel fuel, containing nitrogen in concentration of less than 100 ppm (wt.), sulfur in concentration of less than 50 ppm (wt.), polyaromatic compounds in concentration of less than 11 wt. %and monoaromatic compounds in amount of about 0.5 wt. % up to about 30 wt. % and characterized by an improved cetane index with respect to said cetane index for said distillate feedstock.

EFFECT: invention method ensures production of high-quality low-sulfur and low-nitrogen commercial diesel fuel, which is characterized by considerably lower level of content of aromatic compounds as compared to that which occurs for distillate raw material, demonstrating high value for its high cetane index.

11 cl, 1 dwg