Hydrocarbon dehydrocyclization

Patent metadata

Field	Value
Publication number	US-9815749-B2
Application number	US-201615240830-A
Country	US
Kind code	B2
Filing date	Aug 18, 2016
Priority date	Sep 25, 2015
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

The invention relates to the production of aromatic hydrocarbon by the conversion of a feed comprising saturated hydrocarbon. At least a portion of the saturated hydrocarbon is converted to olefinic hydrocarbon. Aromatic hydrocarbon is produced from at least a portion of the olefinic hydrocarbon using at least one dehydrocyclization catalyst comprising dehydrogenation and molecular sieve components.

First claim

The invention claimed is:

1. A process for producing aromatic hydrocarbon, comprising:
(a) providing a feed comprising ≧1 wt. % of methane;
(b) producing an olefinic product by converting ≧10 wt. % of the feed's methane to C 2 -C 4 olefinic hydrocarbon in a first conversion zone;
(c) providing a dehydrocyclization catalyst having catalytic activity for hydrocarbon dehydrocyclization, wherein the dehydrocyclization catalyst includes a molecular sieve component and a dehydrogenation component;
(d) producing an aromatic product by converting ≧10 wt. % of the olefinic product's C 2 -C 4 olefinic hydrocarbon to aromatic hydrocarbon in the presence of the dehydrocyclization catalyst in a second conversion zone, wherein
(i) the conversion is carried out under conversion conditions which include a temperature in the range of from 400° C. to 700° C., a pressure in the range of from 0 psig (101 kPa) to 300 psig (2170 kPa) and
(ii)the dehydrocyclization catalyst has an average residence time in the conversion zone under the conversion conditions of ≦90 seconds; and

(e) recovering at least a portion of the aromatic product's aromatic hydrocarbon.

2. The process of claim 1 , wherein the feed comprises ≧10 wt. % of methane, and further comprises ≧5 wt. % of C 2+ hydrocarbon.

3. The process of claim 1 , wherein step (b) is carried out by subjecting the feed to one or more of (i) methane pyrolysis conditions, (ii) oxidative coupling conditions, (iii) methane co-conversion conditions, and (iv) oxygenate synthesis followed by oxygenate dehydrogenation or oxygenate-to-olefin processing.

4. The process of claim 1 , wherein (i) the dehydrocyclization catalyst includes ≧25 wt. % of the molecular sieve component and ≧0.05 wt. % of the dehydrogenation component, (ii) the molecular sieve component comprises ≧90 wt. % of one or more of MCM-22, ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-35, and ZSM-48, and (iii) the dehydrogenation component comprises ≧90 wt. % of one or more of Ga, Zn, Cu, Re, Mo, W, La, Fe, Ag, Ni, In, Pt, and Pd.

5. The process of claim 1 , wherein the dehydrocyclization catalyst comprises ≧50 wt. % of the molecular sieve component and ≧1 wt. % of the dehydrogenation component, (ii) the molecular sieve component comprises ≧95 wt. % of H-ZSM- 5 , and (iii) ≧90 wt. % the dehydrogenation component is Ga and/or Zn.

6. The process of claim 1 , wherein the temperature is in the range of from 500° C. to 625° C., the pressure is in the range of from 30 psia (207 kPa) to 80 psia (522 kPa), the average residence time of the dehydrocyclization catalyst in the conversion zone under the conversion conditions is in the range of from 0.001 seconds to 60 seconds, and the conversion conditions further include a space velocity (GHSV) in the range of from 1100 hr −1 to 40,000 hr −1 .

7. The process of claim 1 , wherein the dehydrocyclization catalyst is in the form of a plurality of particles located in a turbulent bed, the bed having a density in the range of from 100 kg/m 3 to 500 kg/m 3 and a superficial fluid velocity in the range of 0.1 m/s to 10 m/s.

8. The process claim 7 , wherein the dehydrocyclization catalyst particles have an average size ≦250 μm and an average density in the range of from 0.6 g/cm 3 to 2 g/cm 3 .

9. The process of claim 8 , wherein (i) the average residence time of the dehydrocyclization catalyst particles in the conversion zone is in the range of from 0.01 seconds to 30 seconds, the bed volume is V B , and (iii) the average residence time is achieved by
(A) removing from the bed at least a portion of the dehydrocyclization catalyst particles at a rate in the range of 0.03 V B /second to 100 V B /second; and
(B) introducing into the bed replacement dehydrocyclization catalyst particles in an amount sufficient to maintain the bed volume V B substantially constant during the conversion, the replacement dehydrocyclization catalyst particles having catalytic activity for dehydrocyclization of the C 2+ non-aromatic hydrocarbon, an average size ≦250 μm, and an average density in the range of from 0.6 g/cm 3 to 2 g/cm 3 .

10. The process of claim 9 , further comprising at least partially regenerating the removed dehydrocyclization catalyst particles, wherein ≧50 wt. % of the replacement dehydrocyclization catalyst particles comprise regenerated catalyst particles.

11. A process for upgrading non-aromatic hydrocarbon, comprising:
(a) providing a feed comprising ≧5 wt. % of C 2 -C 4 paraffinic hydrocarbon;
(b) producing an olefinic product by converting ≧10 wt. % of the feed's C 2 -C 4 paraffinic hydrocarbon to C 2 -C 4 olefinic hydrocarbon in a first conversion zone;
(c) providing a dehydrocyclization catalyst which includes (i) ≧25 wt. % of a molecular sieve component, the molecular sieve component comprising ≧90 wt. % of one or more of MCM-22, ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-35, and ZSM-48, and (ii) ≧0.05 wt. % of a dehydrogenation component, the dehydrogenation component comprising ≧90 wt. % of one or more of Ga, Zn, Cu, Re, Mo, W, La, Fe, Ag, Pt, and Pd;
(d) producing an aromatic product by converting ≧10 wt. % of the olefinic product's C 2 -C 4 olefinic hydrocarbon to aromatic hydrocarbon in the presence of the dehydrocyclization catalyst in a second conversion zone, wherein
(i) the conversion is carried out under conversion conditions which include a temperature in the range of from 400° C. to 700° C., a pressure in the range of from 0 psig (101 kPa) to 300 psig (2170 kPa) and
(ii) the dehydrocyclization catalyst has an average residence time in the conversion zone under the conversion conditions of ≦90 seconds; and

(e) recovering at least a portion of the aromatic product's aromatic hydrocarbon.

12. The process of claim 11 , wherein the gaseous feed comprises 5 mole % to 50 mole % of ethane, 2 mole % to 40 mole % of propane, 0.1 mole % to 30 mole % of i-butane, 1 mole % to 30 mole % of n-butane, and 0.05 mole % to 25 mole % of i-pentane, and further comprises 0 mole % to 95 mole % of methane.

13. The process of claim 11 , wherein step (b) is carried out by subjecting the feed to one or more of (i) hydrocarbon pyrolysis conditions, (ii) oxidative and/or non-oxidative coupling conditions, (iii) catalytic dehydrogenation conditions, (iv) catalytic and/or thermal hydrogen transfer conditions, and (v) C 2+ oxygenate synthesis followed by oxygenate dehydrogenation or oxygenate-to-olefin processing.

14. The process of claim 11 , wherein the conversion of step (d) achieves an aromatic hydrocarbon selectivity ≧40 wt. % and a methane selectivity ≦40 wt. %.

15. The process of claim 11 , wherein (i) the dehydrogenation component comprises ≧95 wt. % of (A) Ga and/or (B) Zn, and (ii) the molecular sieve component comprises ≧95 wt. % H-ZSM-5.

16. The process of claim 11 , wherein during step (d) the average residence time is in the range of from 0.01 second to 30 seconds, the temperature in the range of from 500° C. to 625° C., the pressure in the range of from 30 psia (207 kPa) to 80 psia (522 kPa), and the GHSV is in the range of from 1500 hr −1 to 40,000 hr −1 .

17. The process of claim 11 , wherein the dehydrocyclization catalyst is in the form of a turbulent bed of a plurality of particles, the bed having a density in the range of from 100 kg/m 3 to 500 kg/m 3 and a superficial fluid velocity in the range of 0.1 m/s to 10 m/s.

18. The process claim 17 , wherein particles have an average size ≦250 μm and an average density in the range of from 0.6 g/cm 3 to 2 g/cm 3 .

19. The process of claim 18 , wherein d

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Keusenkothen Paul F
• Harandi Mohsen N
• Buchanan John S
• Shekhar Mayank

Classifications

• C07C1/20

  starting from organic compounds containing only oxygen atoms as heteroatoms · CPC title

• C07C2/78

  Processes with partial combustion · CPC title

• C07C2/76 Primary

  by condensation of hydrocarbons with partial elimination of hydrogen · CPC title

• C07C2/82

  oxidative coupling · CPC title

• C07C2/64

  Addition to a carbon atom of a six-membered aromatic ring · CPC title