Process for Oxidative Desulfurization and Denitrogenation Using A Fluid Catalytic Cracking (FCC) Unit

• US 20120055844A1
• Filed: 09/07/2010
• Published: 03/08/2012
• Est. Priority Date: 09/07/2010
• Status: Active Grant

• Current Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Original Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Inventors: Bourane, Abdennour, Koseoglu, Omer Refa, Kressmann, Stephane Cyrille
• Granted Patent: US 9,574,144 B2
• Time in Patent Office: Days
• US Class Current: 208/87
• CPC Class Codes: C10G 21/06 characterised by the solvent used
• CPC Class Codes: C10G 21/12 Organic compounds only
• CPC Class Codes: C10G 21/16 Oxygen-containing compounds
• CPC Class Codes: C10G 21/22 Compounds containing sulfur, selenium, or tellurium
• CPC Class Codes: C10G 21/28 Recovery of used solvent
• CPC Class Codes: C10G 2300/1074 Vacuum distillates
• CPC Class Codes: C10G 2300/202 Heteroatoms content, i.e. S, N, O, P
• CPC Class Codes: C10G 2300/44 Solvents
• CPC Class Codes: C10G 25/003 Specific sorbent material, not covered by C10G25/02 or C10G25/03
• CPC Class Codes: C10G 27/04 with oxygen or compounds generating oxygen
• CPC Class Codes: C10G 27/12 with oxygen-generating compounds, e.g. per-compounds, chromic acid, chromates plumbites or plumbates C10G19/06
• CPC Class Codes: C10G 53/04 including at least one extraction step
• CPC Class Codes: C10G 53/08 including at least one sorption step
• CPC Class Codes: C10G 53/14 including at least one oxidation step
• CPC Class Codes: C10G 55/06 including at least one catalytic cracking step

Abstract

A method and apparatus for recovering components from a hydrocarbon feedstock is provided. The method includes the steps of (a) supplying a hydrocarbon feedstock to an oxidation reactor, wherein the hydrocarbon feedstock is oxidized in the presence of a catalyst under conditions sufficient to selectively oxidize sulfur compounds and nitrogen compounds present in the hydrocarbon feedstock; (b) separating the hydrocarbons, the oxidized sulfur compounds, and the oxidized nitrogen compounds by solvent extraction; (c) collecting a residue stream that includes the oxidized sulfur compounds and the oxidized nitrogen compounds; and (d) supplying the residue stream to a fluid catalytic cracking unit.

Claims

1. A method of recovering components from a hydrocarbon feedstock, the method comprising the steps of:

supplying the hydrocarbon feedstock to an oxidation reactor, the hydrocarbon feedstock comprising sulfur compounds and nitrogen compounds;

contacting the hydrocarbon feedstock with an oxidizing agent in the oxidation reactor under conditions sufficient to selectively oxidize sulfur compounds and nitrogen compounds present in the hydrocarbon feedstock to produce an oxidized hydrocarbon stream that comprises hydrocarbons, oxidized sulfur compounds, and oxidized nitrogen compounds;

separating the hydrocarbons, the oxidized sulfur compounds, and the oxidized nitrogen compounds in the oxidized hydrocarbon stream by solvent extraction with a polar solvent to produce an extracted hydrocarbon stream and a mixed stream, the mixed stream comprising the polar solvent, the oxidized sulfur compounds, and the oxidized nitrogen compounds, wherein the extracted hydrocarbon stream has a lower concentration of sulfur compounds and nitrogen compounds than the hydrocarbon feedstock;

separating the mixed stream into a first recovered polar solvent stream and a first residue stream, the first residue stream comprising the oxidized sulfur compounds and the oxidized nitrogen compounds; and

supplying the first residue stream to a fluid catalytic cracking unit, the fluid catalytic cracking unit being operative to catalytically crack the oxidized sulfur and the oxidized nitrogen and allow for recovery of hydrocarbons from the first residue stream.

2. The method of claim 1, wherein the oxidant is selected from the group consisting of air, oxygen, peroxides, hydroperoxides, organic peracids, ozone, nitrogen oxides compounds, and combinations thereof.

3. The method of claim 1, wherein the step of contacting the hydrocarbon feedstock with an oxidizing agent occurs in the presence of a catalyst comprising a metal oxide having the formula M_xO_y, wherein M is an element selected from Groups NB, VB, and VIB of the periodic table.

4. The method of claim 1, wherein the sulfur compounds comprise sulfides, disulfides, mercaptans, thiophene, benzothiophene, dibenzothiophene, alkyl derivatives of dibenzothiophene, or combinations thereof.

5. The method of claim 1, wherein the oxidation reactor is maintained at a temperature of between about 20 and about 350°

C. and at a pressure of between about 1 and about 10 bars.

6. The method of claim 1, wherein the ratio of the oxidant to sulfur compounds present in the hydrocarbon feedstock is between about 4:

1 and about 10;

1.

7. The method of claim 1, wherein the polar solvent has a Hildebrandt value of greater than about 19.

8. The method of claim 1, wherein the polar solvent is selected from the group consisting of acetone, carbon disulfide, pyridine, dimethyl sulfoxide, n-propanol, ethanol, n-butanol, propylene glycol, ethylene glycol, dimethlyformamide, acetonitrile, methanol and combinations thereof.

9. The method of claim 1, wherein the polar solvent is acetonitrile.

10. The method of claim 1, wherein the polar solvent is methanol.

11. The method of claim 1, wherein the solvent extraction is conducted at a temperature of between about 20°

C. and about 60°

C. and at a pressure of between about 1 and about 10 bars.

12. The method of claim 1, further comprising the step of supplying the extracted hydrocarbon stream to a stripper to produce a second recovered polar solvent stream and a stripped hydrocarbon stream.

13. The method of claim 12, further comprising the step of supplying the extracted hydrocarbon stream to an adsorption column, the adsorption column being charged with an adsorbent suitable for the removal of oxidized compounds present in the extracted hydrocarbon stream, the adsorption column producing a high purity hydrocarbon product stream and a second residue stream, the second residue stream including a portion of the oxidized compounds

14. The method of claim 13, further comprising supplying the second residue stream to the fluid catalytic cracking unit.

15. The method of claim 13, wherein the adsorbent is selected from the group consisting of activated carbon;

silica gel;

alumina;

natural clays;

silica-alumina;

zeolites;

fresh, used; and

combinations of the same.

16. The method of claim 13, wherein the adsorbent is a polymer coated support, wherein the support has a high surface area and is selected from the group consisting of silica gel;

alumina;

silica-alumina;

zeolites;

fresh, used; and

activated carbon, and the polymer is selected from the group consisting of polysulfone, polyacrylonitrile, polystyrene, polyester terephthalate, polyurethane, and combinations of the same.

17. The method of claim 1, wherein the step of supplying the first residue stream to the fluid catalytic cracking unit further comprises contacting the first residue stream with a fluid catalytic cracking feedstream in the presence of a catalyst to catalytically crack the fluid catalytic cracking feedstream to recover hydrocarbons from the first residue stream.

18. The method of claim 17, wherein the fluid catalytic cracking feedstream comprises vacuum gas oil, reduced crude, demetalized oil, whole crude, cracked shale oil, liquefied coal, cracked bitumen, heavy coker gas oils, light cycle oil (LCO), heavy cycle oil (HCO), clarified slurry oil (CSO), or combinations thereof.

19. A method of recovering components from a hydrocarbon feedstock, the method comprising the steps of:

supplying the hydrocarbon, feedstock to an oxidation reactor, the hydrocarbon feedstock comprising sulfur compounds and nitrogen compounds;

contacting the hydrocarbon feedstock with an oxidizing agent in the oxidation reactor under conditions sufficient to selectively oxidize sulfur compounds and nitrogen compounds present in the hydrocarbon feedstock to produce an oxidized hydrocarbon stream that comprises hydrocarbons, oxidized sulfur compounds, and oxidized nitrogen compounds;

separating the hydrocarbons, the oxidized sulfur compounds, and the oxidized nitrogen compounds in the oxidized hydrocarbon stream by solvent extraction with a polar solvent to produce an extracted hydrocarbon stream and a mixed stream, the mixed stream comprising the polar solvent, the oxidized sulfur compounds, and the oxidized nitrogen compounds, wherein the extracted hydrocarbon stream has a lower concentration of sulfur compounds and nitrogen compounds than the hydrocarbon feedstock;

separating the mixed stream into a first recovered polar solvent stream and a first residue stream, the first residue stream comprising the oxidized sulfur compounds and the oxidized nitrogen compounds;

supplying the first residue stream to a fluid catalytic cracking unit, the fluid catalytic cracking unit being operative to catalytically crack the oxidized sulfur and the oxidized nitrogen and allow for recovery of hydrocarbons from the first residue stream;

contacting the first residue stream with a fluid catalytic cracking feedstream in the presence of a catalyst to catalytically crack the fluid catalytic cracking feedstream to recover hydrocarbons from the first residue stream.

20. The method of claim 19, wherein the oxidant is selected from the group consisting of air, oxygen, peroxides, hydroperoxides, organic peracids, ozone, nitrogen oxides compounds, and combinations thereof.

21. The method of claim 19, wherein the step of contacting the hydrocarbon feedstock with an oxidizing agent occurs in the presence of a catalyst comprising a metal oxide having the formula M_xO_y, wherein M is an element selected from Groups IVB, VB, and VIB of the periodic table.

22. The method of claim 19, wherein the sulfur compounds comprise sulfides, disulfides, mercaptans, thiophene, benzothiophene, dibenzothiophene, alkyl derivatives of dibenzothiophene, or combinations thereof.

23. The method of claim 19, wherein the oxidation reactor is maintained at a temperature of between about 20 and about 350°

C. and at a pressure of between about 1 and about 10 bars.

24. The method of claim 19, wherein the ratio of the oxidant to sulfur compounds present in the hydrocarbon feedstock is between about 4:

1 and about 10;

1.

25. The method of claim 19, wherein the polar solvent has a Hildebrandt value of greater than about 19.

26. The method of claim 19, wherein the polar solvent is selected from the group consisting of acetone, carbon disulfide, pyridine, dimethyl sulfoxide, n-propanol, ethanol, n-butanol, propylene glycol, ethylene glycol, dimethlyformamide, acetonitrile, methanol and combinations thereof.

27. The method of claim 19, wherein the polar solvent is acetonitrile.

28. The method of claim 19, wherein the polar solvent is methanol.

29. The method of claim 19, wherein the solvent extraction is conducted at a temperature of between about 20°

C. and about 60°

C. and at a pressure of between about 1 bar and about 10 bars.

30. The method of claim 19, further comprising the step of supplying the extracted hydrocarbon stream to a stripper to produce a second recovered polar solvent stream and a stripped hydrocarbon stream.

31. The method of claim 19, further comprising the step of supplying the extracted hydrocarbon stream to an adsorption column, the adsorption column being charged with an adsorbent suitable for the removal of oxidized compounds present in the extracted hydrocarbon stream, the absorption column producing a high purity hydrocarbon product stream and a second residue stream, the second residue stream including a portion of the oxidized compounds.

32. The method of claim 31, further comprising supplying the second residue stream to the fluid catalytic cracking unit.

33. The method of claim 31, wherein the adsorbent is selected from the group consisting of activated carbon, silica gel, alumina, natural clays, silica-alumina, zeolites, and combinations of the same.

34. The method of claim 31, wherein the adsorbent is a polymer coated support, wherein the support has a high surface area and is selected from the group consisting of silica gel, alumina, and activated carbon, and the polymer is selected from the group consisting of polysulfone, polyacrylonitrile, polystyrene, polyester terephthalate, polyurethane, silica-alumina, zeolites, and combinations of the same.

35. The method of claim 19, wherein the first residue stream and the fluid catalytic cracking feedstream are present in a weight ratio of the catalyst to the first residue stream and the fluid catalytic cracking feedstream ranges from about 1 to about 15.

36. The method of claim 19, wherein the fluid catalytic cracking feedstream comprises vacuum gas oil, reduced crude, demetalized oil, whole crude, cracked shale oil, liquefied coal, cracked bitumen, heavy coker gas oils, light cycle oil (LCO), heavy cycle oil (HCO), clarified slurry oil (CSO), or combinations thereof.

37. The method of claim 19, wherein the step of contacting the first residue stream with a fluid catalytic cracking feedstream in the presence of a catalyst occurs in a temperature range of about 300°

C. to about 650°

C.

38. The method of claim 19, wherein the step of contacting the first residue stream with a fluid catalytic cracking feedstream in the presence of a catalyst occurs in a residence time of about 1 second to about 10 minutes.

39. The method of claim 19, further comprising the steps of:

a. separating lower boiling components and catalyst particles from the first residue stream and the fluid catalytic cracking feedstream; and

b. regenerating at least a portion of the catalyst particles.

40. The method of claim 39, wherein the step of regenerating at least a portion of the catalyst particles includes contacting the portion of the catalyst particles with a water-free oxygen-containing gas in a fluidized bed operated at conditions to produce regenerated catalyst and gaseous products comprising carbon monoxide and carbon dioxide.

41. The method of claim 39, further comprising the step of adding at least a portion of the regenerated catalyst to the fluid catalytic cracking feedstream.