Pyrolysis tar upgrading process
AssigneeExxonMobil Chemical Patents Inc.
InventorsDavid T. Ferrughelli, Emmanuel Ulysse, Teng Xu
Life of this patent
Estimating the term…
Abstract
A process for upgrading pyrolysis tar to higher value products. More particularly, this invention relates to the upgrading of steam cracker tar using relatively small amounts of a transition metal sulfide-containing particulate catalyst dispersed throughout the tar chargestock and in the presence of hydrogen, at relatively mild hydroconversion conditions.
Claims25
A process for upgrading pyrolysis tar, which process comprises conducting a chargestock comprising pyrolysis tar, without added solvent or utility fluid, to a hydroprocessing zone and reacting the chargestock in the hydroprocessing zone in the presence of a hydrogen-containing gas at hydroprocessing conditions including a temperature of from about 380° C. to about 425° C. and a hydrogen partial pressure of from about 34 bar gauge to about 82 bar gauge, which chargestock, during hydroconversion, has dispersed therein, in particulate form, a transition metal sulfide catalyst, wherein (i) the transition metal content is from about 10 ppmw to about 1000 ppmw, based on the weight of the chargestock and (ii) the transition metal is selected from groups 4 to 10 of the Periodic Table of the Elements.
A process for upgrading steam cracker tar, which process comprises:
- (a) providing a chargestock comprising steam cracker tar, without added solvent or utility fluid;
- (b) adding to the chargestock an oil-soluble transition metal compound in an amount in the range from about 10 to about 1000 weight parts per million, based on the weight of the chargestock, the transition metal being selected from the group consisting of molybdenum, chromium, vanadium, and mixtures thereof;
- (c) reacting the chargestock containing the oil-soluble transition metal compound in a hydroprocessing zone at hydroprocessing conditions including a temperature in the range of from about 380° C. to about 425° C. and a hydrogen partial pressure in the range of from about 34 bar gauge to about 82 bar gauge, to (i) form a transition metal sulfide catalyst in-situ during the hydroprocessing and (ii) produce a hydroprocessor effluent comprising (A) a gaseous phase, (B) hydroprocessed pyrolysis tar, and (C) catalytic solids;
- and
- (d) recovering the hydroprocessed pyrolysis tar.
Dependencies are inferred from the claim text.