INTEGRATED DESULFURIZATION AND DENITRIFICATION PROCESS INCLUDING MILD HYDROTREATING OF AROMATIC-LEAN FRACTION AND OXIDATION OF AROMATIC-RICH FRACTION

• US 20120152804A1
• Filed: 12/15/2010
• Published: 06/21/2012
• Est. Priority Date: 12/15/2010
• Status: Active Grant

• Current Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Original Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Inventors: Koseoglu, Omer Refa, Bourane, Abdennour, Al-Shahrani, Farhan M., Al-Shafi, Emad
• Granted Patent: US 8,741,128 B2
• Time in Patent Office: Days
• US Class Current: 208/80
• CPC Class Codes: B01J 19/006 Baffles
• CPC Class Codes: B01J 19/18 Stationary reactors having moving elements inside B01J19/08, B01J19/26 take precedence
• CPC Class Codes: B01J 2219/00768 vertical
• CPC Class Codes: B01J 2219/00777 horizontal
• CPC Class Codes: C10G 21/00 Refining of hydrocarbon oils, in the absence of hydrogen, by extraction with selective solvents C10G17/00, C10G19/00 take precedence
• CPC Class Codes: C10G 21/16 Oxygen-containing compounds
• CPC Class Codes: C10G 21/20 Nitrogen-containing compounds
• CPC Class Codes: C10G 21/27 Organic compounds not provided for in a single one of groups C10G21/14 - C10G21/26
• CPC Class Codes: C10G 2300/1096 Aromatics or polyaromatics
• 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 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 27/14 with ozone-containing gases
• CPC Class Codes: C10G 45/02 to eliminate hetero atoms without changing the skeleton of the hydrocarbon involved and without cracking into lower boiling hydrocarbons; Hydrofinishing
• CPC Class Codes: C10G 45/22 with hydrogen dissolved or suspended in the oil
• CPC Class Codes: C10G 67/0418 The hydrotreatment being a hydrorefining
• CPC Class Codes: C10G 67/12 including oxidation as the refining step in the absence of hydrogen
• CPC Class Codes: C10G 67/14 including at least two different refining steps in the absence of hydrogen

Abstract

Deep desulfurization of hydrocarbon feeds containing undesired organosulfur and organonitrogen compounds to produce a hydrocarbon product having low levels of sulfur-containing and nitrogen-containing compounds, is achieved by first subjecting the entire feed to an extraction zone to separate an aromatic-rich fraction containing a substantial amount of the refractory organosulfur and organonitrogen compounds and an aromatic-lean fraction containing a substantial amount of the labile organosulfur and organonitrogen compounds. The aromatic-lean fraction is contacted with a hydrotreating catalyst in a hydrotreating reaction zone operating under mild conditions to convert the labile organosulfur and organonitrogen compounds. The aromatic-rich fraction is oxidized to convert the refractory organosulfur and organonitrogen compounds to oxidized organosulfur and organonitrogen compounds. These oxidized organosulfur and organonitrogen compounds are subsequently removed, producing a stream containing reduced levels of organosulfur and organonitrogen compounds.

Claims

1. A method of processing a hydrocarbon feed to remove undesired aromatic and non-aromatic organosulfur compounds comprising:

subjecting the hydrocarbon feed and an effective quantity of extraction solvent to an extraction zone to produce

an extract containing a major proportion of the aromatic content of the hydrocarbon feed and a portion of the extraction solvent and

a raffinate containing a major proportion of the non-aromatic content of the hydrocarbon feed and a portion of the extraction solvent;

separating at least substantial portion of the extraction solvent from the raffinate and retaining an aromatic-lean fraction;

separating at least substantial portion of the extraction solvent from the extract and retaining an aromatic-rich fraction;

subjecting the aromatic-lean fraction to a hydrotreating process to thereby reduce the sulfur content; and

contacting the aromatic-rich fraction with an oxidizing agent and an oxidizing catalyst to convert aromatic organosulfur compounds to oxides.

2. The method of claim 1, wherein the hydrocarbon feed further includes undesired aromatic and non-aromatic organonitrogen compounds, the step of subjecting the aromatic-lean fraction to a hydrotreating process also lowers the content of labile organonitrogen compounds, and the step of contacting the aromatic-rich fraction with the oxidizing agent and the oxidizing catalyst also convert aromatic organonitrogen compounds to oxides

3. The method of claim 1, wherein the hydrodesulfurizing process is operated at mild operating conditions.

4. The method of claim 3, wherein the hydrotreating process operates with a hydrogen partial pressure of about 10 bars to about 40 bars.

5. The method of claim 3, wherein the hydrotreating process operates with a hydrogen partial pressure of about 10 bars to about 30 bars.

6. The method of claim 3, wherein the hydrotreating process operates with a hydrogen partial pressure of about 20 bars.

7. The method of claim 3, wherein the hydrotreating process operates with an operating temperature of about 300°

C. to about 400°

C.

8. The method of claim 3, wherein the hydrotreating process operates with an operating temperature of about 300°

C. to about 360°

C.

9. The method of claim 3, wherein hydrotreating process operates with an operating temperature of about 300°

C. to about 340°

C.

10. The method of claim 3, wherein the hydrogen feed rate in the hydrotreating process step is from about 100 liters of hydrogen per liter of oil to about 500 liters of hydrogen per liter of oil.

11. The method of claim 3, wherein the hydrogen feed rate in the hydrotreating process step is from about 100 liters of hydrogen per liter of oil to about 300 liters of hydrogen per liter of oil.

12. The method of claim 3, wherein the hydrogen feed rate in the hydrotreating process step is from about 100 liters of hydrogen per liter of oil to about 200 liters of hydrogen per liter of oil.

13. The method of claim 1, wherein the oxidizing agent is selected from the group consisting of hydrogen peroxide, organic peroxides such as ter-butyl hydroperoxide, peroxo acids, oxides of nitrogen, oxygen, ozone and air.

14. The method of claim 1, wherein the oxidizing catalyst is selected from the group consisting of homogeneous catalysts and heterogeneous catalysts.

15. The method of claim 14, wherein the oxidizing catalyst includes a metal from Group IVB to Group VIIIB of the Periodic Table.

16. The method of claim 1, further comprising separating the oxidizing agent and oxidizing catalyst from the oxidized aromatic-rich fraction.

17. The method of claim 16, wherein the oxidizing agent is separated by solvent extraction.

18. The method of claim 1, further comprising recovering a hydrotreated hydrocarbon product.

19. The method of claim 1, further comprising recovering a hydrocarbon product subjected to oxidative desulfurization.

20. The method of claim 1, further comprising combining the aromatic-lean fraction that has been subjected to the hydrotreating process and the aromatic-rich fraction that has been subjected to oxidation to provide a reduced-organosulfur content hydrocarbon product.

21. The method of claim 1, wherein the extraction solvent is selected from the group consisting of furfural, N-methyl-2-pyrrolidone, dimethylformamide and dimethylsulfoxide.

22. The method of claim 1, wherein the extraction solvent is provided in a solvent to oil ratio of 20:

1.

23. The method of claim 1, wherein the extraction solvent is provided in a solvent to oil ratio of 4:

1.

24. The method of claim 1, wherein the extraction solvent is provided in a solvent to oil ratio of 1:

1.

25. The method of claim 1, wherein the extraction zone operates at a temperature of about 20°

C. to about 120°

C.

26. The method of claim 1, wherein the extraction zone operates at a temperature of about 40°

C. to about 80°

C.

27. The method of claim 1, wherein the extraction zone operates at a pressure of about 1 bar to about 10 bars.

28. The method of claim 1, wherein the extraction zone operates at a pressure of about 1 bar to about 3 bars.

29. An apparatus for processing a hydrocarbon feed containing undesired organosulfur compounds comprising:

an extraction zone operable to extract aromatic organosulfur compounds from the hydrotreated effluent, the aromatic zone extraction including

an inlet for receiving the hydrocarbon feed and an inlet for receiving extraction solvent,

a raffinate outlet for discharging a raffinate containing a major proportion of the non-aromatic content of the hydrocarbon feed and a portion of the extraction solvent, and

an extract outlet for discharging an extract containing a major proportion of the aromatic content of the hydrocarbon feed and a portion of the extraction solvent;

a hydrotreating zone having an inlet in fluid communication with the raffinate outlet and an outlet for discharging hydrotreated effluent; and

an oxidation zone containing an oxidation catalyst and an oxidizing agent, the oxidation zone having an inlet in fluid communication with the extract outlet and an outlet for discharging oxidized effluent.