Process for methane conversion

• US 20070293709A1
• Filed: 04/02/2007
• Published: 12/20/2007
• Est. Priority Date: 04/21/2006
• Status: Active Grant

• Current Assignee: ExxonMobil Chemical Patents Inc. (Exxon Mobil Corporation)
• Original Assignee: ExxonMobil Chemical Patents Inc. (Exxon Mobil Corporation)
• Inventors: Sangar, Neeraj, Iaccino, Larry, Vincent, Matthew, Stavens, Elizabeth
• Granted Patent: US 7,781,636 B2
• Time in Patent Office: Days
• US Class Current: 585/312
• CPC Class Codes: C07C 15/02 Monocyclic hydrocarbons
• CPC Class Codes: C07C 15/04 Benzene
• CPC Class Codes: C07C 2/76 by condensation of hydrocarbons with partial elimination of hydrogen
• CPC Class Codes: C10G 2300/1025 Natural gas
• CPC Class Codes: C10G 2400/30 Aromatics
• CPC Class Codes: C10G 50/00 Production of liquid hydrocarbon mixtures from lower carbon number hydrocarbons, e.g. by oligomerisation
• CPC Class Codes: Y02P 20/52 using catalysts, e.g. selective catalysts
• CPC Class Codes: Y10S 585/943 Synthesis from methane or inorganic carbon source, e.g. coal

Abstract

A process for converting methane to higher hydrocarbon(s) including aromatic hydrocarbon(s) in a reaction zone comprises providing to a hydrocarbon feedstock containing methane and a catalytic particulate material to the reaction zone and contacting the catalytic particulate material and the hydrocarbon feedstock in a substantially countercurrent fashion in the reaction zone, while operating the reaction zone under reaction conditions sufficient to convert at least a portion of said methane to a first effluent having said higher hydrocarbon(s).

Claims

1. A process for converting methane to higher hydrocarbon(s) including aromatic hydrocarbon(s) in a reaction zone, the process comprising:

(a) providing to said reaction zone a hydrocarbon feedstock containing methane;

(b) providing to said reaction zone a catalytic particulate material;

(c) contacting said catalytic particulate material and said hydrocarbon feedstock in a substantially countercurrent fashion;

(d) maintaining the hydrodynamics of said reaction zone in settling bed regime; and

(e) operating said reaction zone under reaction conditions sufficient to convert at least a portion of said methane to a first effluent having said higher hydrocarbon(s).

2. The process recited in claim 1, further comprising steps of separating unreacted methane from said higher hydrocarbon(s) and recycling said unreacted methane to said reaction zone.

3. The process recited in claim 1, wherein said first effluent also comprises hydrogen and the process further comprises (i) separating at least part of said hydrogen from said first effluent or (ii) reacting at least part of said hydrogen from said first effluent with oxygen-containing specie(s) to produce a second effluent having a reduced hydrogen content compared with said first effluent.

4. The process recited in claim 3 further comprising recycling said second effluent to (a).

5. The process recited in claim 1, wherein said reaction zone is operated at a gas velocity of less than 0.99 times of the minimum fluidizing velocity.

6. The process recited in claim 1, wherein (a) further comprises providing a non-catalytic particulate material to said reaction zone.

7. The process recited in claim 6, wherein the mass ratio of the total flowrate of said particulate material (catalytic particulate material plus any non-catalytic particulate material) to the flowrate of said hydrocarbon feedstock is from about 1:

1 to about 40;

1.

8. The process recited in claim 1, wherein said reaction zone is located in a cold wall reactor.

9. The process recited in claim 1, wherein said reaction conditions are non-oxidizing conditions.

10. The process recited in claim 1, wherein said reaction conditions include a temperature of about 400°

C. to about 1200°

C., a pressure of about 1 kPa-a to about 1000 kpa-a, and a weight hourly space velocity of about 0.01 hr<sup>−

1</sup> to about 1000 hr<sup>−

1</sup>.

11. The process recited in claim 1, wherein said conditions are sufficient to convert at least 5 wt. % of said methane to said aromatic hydrocarbon(s).

12. The process recited in claim 1, wherein said catalytic particulate material comprises a metal or compound thereof on an inorganic support.

13. The process recited in claim 1, wherein said catalytic particulate material comprises at least one of molybdenum, tungsten, rhenium, a molybdenum compound, a tungsten compound, a zinc compound, and a rhenium compound on ZSM-5, silica or an aluminum oxide.

14. The process recited in claim 1, wherein at least 90 wt. % said catalytic particulate material has particle size from about 0.1 mm to about 100 mm.

15. The process recited in claim 1, wherein said catalytic particulate material enters said reaction zone at a temperature of about 800°

C. to about 1200°

C. and exits said reaction zone at a temperature of about 500°

C. to about 800°

C.

16. The process recited in claim 15, wherein the temperature difference of said catalytic particulate material across said reaction zone is at least 100°

C.

17. The process recited in claim 1, wherein said hydrocarbon feedstock further comprises at least one of CO₂, CO, H₂, H₂O, or C₂+ hydrocarbon(s).

18. The process recited in claim 1, and further comprising:

(f) removing at least a portion of said catalytic particulate material from said reaction zone;

(g) regenerating at least a portion of the removed catalytic particulate material under regenerating conditions; and

(h) recycling at least a portion of the regenerated catalytic particulate material to said reaction zone.

19. The process recited in claim 18, wherein said regenerating is conducted at a temperature from about 400°

C. to about 750°

C. in the presence of a regeneration gas comprising oxygen.

20. The process recited in claim 19, wherein said regeneration gas further contains carbon dioxide and/or nitrogen such that the oxygen concentration of said regeneration gas is from about 2 wt. % to about 10 wt. %.

21. The process recited in claim 18, wherein said regenerating is conducted at a temperature from about 800°

C. to about 1200°

C. in the presence of a regeneration gas comprising hydrogen.

22. A process for converting methane to higher hydrocarbon(s) including aromatic hydrocarbon(s) in a reaction zone, the process comprising:

(a) providing to said reaction zone a hydrocarbon feedstock containing methane;

(b) providing to said reaction zone a catalytic particulate material;

(c) contacting said catalytic particulate material and said hydrocarbon feedstock in a substantially countercurrent fashion;

(d) maintaining the temperature profile of said reaction zone with an inverse temperature profile; and

(e) operating said reaction zone under reaction conditions sufficient to convert at least a portion of said methane to a first effluent comprising said higher hydrocarbon(s).

23. The process recited in claim 22, wherein the reaction zone includes a catalyst engaging portion, where said hydrocarbon feedstock first contacts said catalytic particulate material in said reaction zone and a catalyst disengaging portion, where said first effluent disengages from contact with said catalytic particulate material in said reaction zone, and wherein the temperature profile of said reaction zone is maintained such that the difference between the temperature of said first effluent at the catalyst disengaging portion and the temperature of said hydrocarbon feedstock at the catalyst engaging portion is at least +10°

C.

24. The process recited in claim 23, wherein the difference between the temperature of said first effluent at the catalyst disengaging portion and the temperature of said hydrocarbon feedstock at the catalyst engaging portion is at least +50°

C.

25. The process recited in claim 23, wherein the difference between the temperature of said first effluent at the catalyst disengaging portion and the temperature of said hydrocarbon feedstock at the catalyst engaging portion is at least +100°

C.

26. The process recited in claim 22, wherein said first effluent also comprises hydrogen and the process further comprises (i) separating at least part of said hydrogen from said first effluent or (ii) reacting at least part of said hydrogen from said first effluent with oxygen-containing specie(s) to produce a second effluent having a reduced hydrogen content compared with said first effluent.

27. The process recited in claim 22, wherein said reaction zone is operated in settling bed regime.

28. The process recited in claim 22, wherein said reaction zone is operated at a gas velocity of less than 0.99 times of the minimum fluidizing velocity.

29. The process recited in claim 22, wherein (a) further comprises providing a non-catalytic particulate material to said reaction zone.

30. The process recited in claim 29, wherein the mass ratio of the total flowrate of said particulate material (catalytic particulate material plus any non-catalytic particulate material) to the flowrate of said hydrocarbon feedstock is from about 1:

1 to about 40;

1.

31. The process recited in claim 22, wherein said catalytic particulate material comprises at least one of molybdenum, tungsten, rhenium, a molybdenum compound, a tungsten compound, a zinc compound, and a rhenium compound on ZSM-5, silica or an aluminum oxide.

32. The process recited in claim 22, wherein said catalytic particulate material enters said reaction zone at a temperature of about 800°

C. to about 1200°

C. and exits said reaction zone at a temperature of about 500°

C. to about 800°

C.

33. The process recited in claim 22, and further comprising:

(f) removing at least a portion of said catalytic particulate material from said reaction zone;

(g) regenerating at least a portion of the removed catalytic particulate material under regenerating conditions; and

(h) recycling at least a portion of the regenerated catalytic particulate material to said reaction zone.

34. A process for converting methane to higher hydrocarbon(s) including aromatic hydrocarbon(s) in a reaction zone, the process comprising:

(a) supplying said reaction zone with a hydrocarbon feedstock containing methane and a catalytic particulate material in a substantially countercurrent fashion;

(b) operating said reaction zone such that said catalytic particulate material is substantially free of fluidization and under reaction conditions effective to convert at least a portion of said methane to a first effluent having said higher hydrocarbon(s);

(c) removing at least a portion of said catalytic particulate material from said reaction zone;

(d) regenerating at least a portion of the removed catalytic particulate material under regenerating conditions;

(e) heating at least a portion of the removed catalytic particulate material and/or at least a portion of the regenerated catalytic particulate material to a temperature from about 800 to about 1200°

C.; and

(f) recycling at least a portion of the heated catalytic particulate material of (e) to said reaction zone.

35. The process recited in claim 34, wherein said first effluent also comprises hydrogen and the process further comprises (i) separating at least part of said hydrogen from said first effluent or (ii) reacting at least part of said hydrogen from said first effluent with oxygen-containing specie(s) to produce a second effluent having a reduced hydrogen content compared with said first effluent.

36. The process recited in claim 35 and further comprising recycling said second effluent to (a).

37. The process recited in claim 34, wherein said reaction zone is operated in settling bed regime.

38. The process recited in claim 34 wherein (a) further comprises providing a non-catalytic particulate material to said reaction zone.

39. The process recited in claim 38, wherein the mass ratio of the total flowrate of said particulate material (catalytic particulate material plus any non-catalytic particulate material) to the flowrate of said hydrocarbon feedstock is from about 1:

1 to about 40;

1.

40. The process recited in claim 34, wherein said catalytic particulate material comprises at least one of molybdenum, tungsten, rhenium, a molybdenum compound, a tungsten compound, a zinc compound, and a rhenium compound on ZSM-5, silica or an aluminum oxide.

41. The process recited in claim 34, wherein said catalytic particulate material enters said reaction zone at a temperature of about 800°

C. to about 1200°

C. and exits said reaction zone at a temperature of about 500°

C. to about 800°

C.

42. A process for converting methane to higher hydrocarbon(s) including aromatic hydrocarbon(s) in a reaction zone, the process comprising:

a. supplying said reaction zone with a hydrocarbon feedstock containing methane and a catalytic particulate material in a substantially countercurrent fashion;

b. operating said reaction zone under reaction conditions effective to convert at least a portion of said methane to a first effluent having said higher hydrocarbon(s);

c. removing at least a portion of said catalytic particulate material from said reaction zone;

d. heating at least a portion of the removed catalytic particulate material to a temperature from about 800 to about 1200°

C.; and

e. regenerating at least a portion of the removed catalytic particulate material under regenerating conditions; and

f. recycling at least a portion of the heated catalytic particulate material of (d) and/or at least a portion of said regenerated catalyst of (e) to said reaction zone.

43. The process recited in claim 42, wherein said first effluent also comprises hydrogen and the process further comprises (i) separating at least part of said hydrogen from said first effluent or (ii) reacting at least part of said hydrogen from said first effluent with oxygen-containing specie(s) to produce a second effluent having a reduced hydrogen content compared with said first effluent.

44. The process recited in claim 42, wherein said reaction zone is operated in settling bed regime.

45. The process recited in claim 42, wherein said reaction zone is operated at a gas velocity of less than 0.99 times of the minimum fluidizing velocity.

46. The process recited in claim 42, wherein the temperature profile of said reaction zone is maintained as an inverse temperature profile.

47. The process recited in claim 46, wherein the reaction zone includes a catalyst engaging portion, where said hydrocarbon feedstock first contacts said catalytic particulate material in said reaction zone and a catalyst disengaging portion, where said first effluent disengages from contact with said catalytic particulate material in said reaction zone, and wherein the temperature profile of said reaction zone is maintained such that the difference between the temperature of said first effluent at the catalyst disengaging portion and the temperature of said hydrocarbon feedstock at the catalyst engaging portion is at least +10°

C.

48. The process recited in claim 42, wherein said catalytic particulate material comprises at least one of molybdenum, tungsten, rhenium, a molybdenum compound, a tungsten compound, a zinc compound, and a rhenium compound on ZSM-5, silica or an aluminum oxide.

49. The process recited in claim 42, wherein said catalytic particulate material enters said reaction zone at a temperature of about 800°

C. to about 1200°

C. and exits said reaction zone at a temperature of about 500°

C. to about 800°

C.

50. A process for manufacturing aromatic hydrocarbon(s) from methane in a reaction zone, the process comprising:

(a) providing to said reaction zone a hydrocarbon feedstock containing methane;

(b) providing to said reaction zone a catalytic particulate material;

(c) contacting said catalytic particulate material and said hydrocarbon feedstock in a substantially countercurrent fashion;

(d) maintaining temperature profile of said reaction zone as a inverse temperature profile; and

(e) operating said reaction zone under reaction conditions sufficient to convert at least a portion of said methane to a first effluent having said aromatic hydrocarbon(s); and

(f) recovering said aromatic hydrocarbon(s) from said first effluent.

51. The process recited in claim 50, and comprising recovering benzene from said first effluent.

52. The process recited in claim 50, wherein the reaction zone includes a catalyst engaging portion, where said hydrocarbon feedstock first contacts said catalytic particulate material in said reaction zone and a catalyst disengaging portion, where said first effluent disengages from contact with said catalytic particulate material in said reaction zone, and wherein the temperature profile of said reaction zone is maintained such that the difference between the temperature of said first effluent at the catalyst disengaging portion and the temperature of said hydrocarbon feedstock at the catalyst engaging portion is at least +10°

C.

53. The process recited in claim 50, wherein said first effluent also comprises hydrogen and the process further comprises (i) separating at least part of said hydrogen from said first effluent or (ii) reacting at least part of said hydrogen from said first effluent with oxygen-containing specie(s) to produce a second effluent having a reduced hydrogen content compared with said first effluent.

54. The process recited in claim 50, wherein said reaction zone is operated in settling bed regime.

55. The process recited in claim 50, wherein said catalytic particulate material comprises at least one of molybdenum, tungsten, rhenium, a molybdenum compound, a tungsten compound, a zinc compound, and a rhenium compound on ZSM-5, silica or an aluminum oxide.

56. The process recited in claim 50, wherein said catalytic particulate material enters said reaction zone at a temperature of about 800°

C. to about 1200°

C. and exits said reaction zone at a temperature of about 500°

C. to about 800°

C.

57. The process recited in claim 50, and further comprising:

(g) removing at least a portion of said catalytic particulate material from said reaction zone;

(h) regenerating at least a portion of the removed catalytic particulate material under regenerating conditions; and

(i) recycling at least a portion of the regenerated catalytic particulate material to said reaction zone

58. The process of claim 50, and further comprising contacting at least a portion of said aromatic hydrocarbon(s) with a feed containing hydrogen to produce a product having saturates and/or single ring aromatic hydrocarbon(s).

59. The process of claim 50, and further comprising contacting at least a portion of said aromatic hydrocarbon(s) with a feed containing an alkylating agent to produce a product having xylene(s), ethylbenzene, cumene, or toluene.