Method of enhancing an aromatization catalyst

• US 8,569,555 B2
• Filed: 04/01/2011
• Issued: 10/29/2013
• Est. Priority Date: 07/28/2006
• Status: Active Grant

• Current Assignee: Chevron Phillips Chemical Company LP (Chevron Corp.)
• Original Assignee: Chevron Phillips Chemical Company LP (Chevron Corp.)
• Inventors: Brown, Scott H., Cheung, Tin-Tack Peter, Glova, David J., Hasenberg, Daniel M., Holtermann, Dennis L., Khare, Gyanesh P., Knorr, Daniel B. Jr., Blessing, Christopher D.
• Primary Examiner(s): Dang, Thuan D
• Application Number:
  US13/078,521
• Publication Number:
  US 20110190559A1
• Time in Patent Office: 942 Days
• Field of Search: 585/418, 585/419, 208/137, 208/138, 208/139
• US Class Current: 585/418
• CPC Class Codes: C10G 2300/4081 Recycling aspects
• CPC Class Codes: C10G 2400/30 Aromatics
• CPC Class Codes: C10G 35/095 containing crystalline alumino-silicates, e.g. molecular sieves C10G35/065 takes precedence

Abstract

A hydrocarbon aromatization process comprising adding a nitrogenate, an oxygenate, or both to a hydrocarbon stream to produce an enhanced hydrocarbon stream, and contacting the enhanced hydrocarbon stream with an aromatization catalyst, thereby producing an aromatization reactor effluent comprising aromatic hydrocarbons, wherein the catalyst comprises a non-acidic zeolite support, a group VIII metal, and one or more halides. Also disclosed is a hydrocarbon aromatization process comprising monitoring the presence of an oxygenate, a nitrogenate, or both in an aromatization reactor, monitoring at least one process parameter that indicates the activity of the aromatization catalyst, modifying the amount of the oxygenate, the nitrogenate, or both in the aromatization reactor, thereby affecting the parameter.

Claims

1. A hydrocarbon aromatization process comprising:

adding an oxygenate to a recycle stream to produce an enhanced recycle stream, to a hydrocarbon stream to produce an enhanced hydrocarbon stream, or to both, wherein the enhanced hydrocarbon stream, the enhanced recycle stream, or both contains from about 2 ppm to 12 ppm water;

contacting the enhanced recycle stream, the enhanced hydrocarbon stream, or both with an aromatization catalyst in a reaction zone, wherein the catalyst comprises a non-acidic zeolite support, a group VIII metal, a chloride, and a fluoride; and

recovering an effluent comprising aromatic hydrocarbons.

2. The process of claim 1 further comprising separating a stream from the effluent to produce the hydrogen recycle stream, wherein the hydrogen recycle stream has a water content of from about 1 ppmv to about 100 ppmv.

3. The process of claim 2 further comprising treating the hydrogen recycle stream to remove all or a portion of any oxygenates therein to produce a treated hydrogen recycle stream having a water content of less than about 1 ppmv and then adding the oxygenate to the treated hydrogen recycle stream prior to addition to the hydrocarbon stream.

4. The process of claim 1 further comprising controlling the addition of the oxygenate to the recycle stream to maintain one or more process parameters within a desired range.

5. The process of claim 1 further comprising controlling the addition of the oxygenate to the recycle stream to increase the production of one or more aromatic compounds in the reaction zone effluent by at least about 1 percent over pre-addition levels.

6. The process of claim 1 further comprising controlling the addition of the oxygenate to the recycle stream to increase the catalyst selectivity to benzene in the reaction zone effluent by at least about 1 percent over pre-addition levels.

7. The process of claim 3 wherein the oxygenate removed from the recycle stream comprises water.

8. The process of claim 1 wherein the aromatization process comprises a plurality of reactors, and the oxygenate is added to one or more of the reactors.

9. The process of claim 1 wherein the oxygenate is oxygen, oxygen-containing compounds, water, carbon dioxide, hydrogen peroxide, an alcohol, ozone, carbon monoxide, ketones, esters, aldehydes, carboxylic acids, lactones, or combinations thereof.

10. The process of claim 1 wherein the oxygenate is methanol, ethanol, propanol, isopropanol, butanol, t-butanol, pentanol, amyl alcohol, hexanol, cyclohexanol, phenol, or combinations thereof.

11. The process of claim 1 wherein the non-acidic zeolite support is zeolite L, zeolite X, zeolite Y, zeolite omega, beta, mordenite, or combinations thereof, and the Group VIII metal is platinum.

12. The process of claim 1 further comprising:

controlling the addition of the oxygenate to the enhanced hydrocarbon stream, the enhanced recycle stream, or both in order to maintain one or more process parameters within a desired range.

13. The process of claim 4 wherein the oxygenate addition is controlled to maintain a T_eq across one or more reactors in the process.

14. The process of claim 13 wherein the T_eq in the one or more reactors is decreased in comparison to a T_eq that occurs in the absence of the oxygenate.

15. The process of claim 14 wherein the T_eq decreases from about 0.1 percent to about 25 percent.

16. The process of claim 1 wherein the oxygenate is used in combination with a nitrogenate.

17. The process of claim 1 wherein the oxygenate addition is controlled to maintain a T_eq across one or more reactors in the process.

18. The process of claim 17 wherein the T_eq in the one or more reactors is decreased in comparison to a T_eq that occurs in the absence of the oxygenate.

19. The process of claim 18 wherein the T_eq decreases from about 0.1 percent to about 25 percent.

20. The process of claim 12 wherein the non-acidic zeolite support is zeolite L, zeolite X, zeolite Y, zeolite omega, beta, mordenite, or combinations thereof, and the Group VIII metal is platinum.

21. A hydrocarbon aromatization process comprising:

adding an oxygenate to a recycle stream to produce an enhanced recycle stream, to a hydrocarbon stream to produce an enhanced hydrocarbon stream, or to both, wherein the enhanced hydrocarbon stream, the enhanced recycle stream, or both contains from about 2 ppm to 12 ppm water;

contacting the enhanced recycle stream, the enhanced hydrocarbon stream, or both with an aromatization catalyst in a reaction zone, wherein the catalyst comprises a non-acidic zeolite support, a group VIII metal, a fluoride, and one or more other halides; and

recovering an effluent comprising aromatic hydrocarbons.

22. The process of claim 21 wherein the one or more other halides comprises chloride and bromide.

23. A hydrocarbon aromatization process comprising:

adding an oxygenate to a recycle stream to produce an enhanced recycle stream containing from about 2 ppm to 12 ppm water;

contacting the enhanced recycle stream with an aromatization catalyst in a reaction zone, wherein the catalyst comprises a non-acidic L-zeolite support, platinum and one or more halides; and

recovering an effluent comprising aromatic hydrocarbons.