Process for producing olefins

• US 7,288,692 B2
• Filed: 07/14/2004
• Issued: 10/30/2007
• Est. Priority Date: 07/14/2004
• Status: Active Grant

• Current Assignee: ExxonMobil Chemical Patents Inc. (Exxon Mobil Corporation)
• Original Assignee: ExxonMobil Chemical Patents Inc. (Exxon Mobil Corporation)
• Inventors: Brinen, Jeffrey L., Kuechler, Keith H., Ruziska, Philip A.
• Primary Examiner(s): Caldarola; Glenn
• Assistant Examiner(s): BULLOCK, IN SUK C
• Application Number:
  US10/891,726
• Publication Number:
  US 20060014990A1
• Time in Patent Office: 1,203 Days
• Field of Search: 585/640, 585/809, 585/802, 585/638, 585/639
• US Class Current: 585/809
• CPC Class Codes: C07C 1/20 starting from organic compounds containing only oxygen atoms as heteroatoms
• CPC Class Codes: C07C 11/02 Alkenes
• CPC Class Codes: C07C 7/005 Processes comprising at least two steps in series
• CPC Class Codes: C07C 7/10 by extraction, i.e. purification or separation of liquid hydrocarbons with the aid of liquids
• CPC Class Codes: Y02P 30/20 using bio-feedstock
• CPC Class Codes: Y02P 30/40 Ethylene production

Abstract

A process is described for producing olefins from a vapor product stream from an oxygenate to olefin conversion reaction, the vapor product stream comprising C₂ to C₄ olefins, C₅+ hydrocarbons, at least one oxygenate and water. In the process, the vapor product stream is cooled to remove water therefrom and produce a first vapor effluent stream. The first vapor effluent stream is then cooled and compressed to produce a condensed liquid effluent stream comprising C₅+ hydrocarbons and at least one oxygenate, and a residual vapor effluent stream comprising C₂ to C₄ olefins. At least part of the condensed liquid effluent stream is contacted with a liquid water-containing stream in a liquid-liquid contacting device to at least partly separate said condensed liquid effluent stream, or portion thereof, into an aqueous phase rich in said at least one oxygenate and an organic phase rich in said C₅+ hydrocarbons.

Claims

1. A process for producing olefins comprising:

(a) providing a vapor product stream from an oxygenate to olefin conversion reaction comprising C₂ to C₄ olefins, C₅+ hydrocarbons, at least one oxygenate and water;

(b) cooling the vapor product stream to remove water therefrom and produce a first vapor effluent stream;

(c) compressing and cooling the first vapor effluent stream to produce a condensed liquid effluent stream comprising C₅+ hydrocarbons and at least one oxygenate, and a residual vapor effluent stream comprising C₂ to C₄ olefins; and

(d) contacting at least a portion of the condensed liquid effluent steam with a liquid water-containing stream in a liquid-liquid contacting device to at least partly separate said condensed liquid effluent stream, or portion thereof, into an aqueous phase rich in said at least one oxygenate and an organic phase rich in said C₅+ hydrocarbons.

2. The process of claim 1 wherein said at least one oxygenate includes methanol.

3. The process of claim 2 wherein said vapor product stream in (a) comprises from about 1 wt. % to about 10 wt. % methanol.

4. The process of claim 1 wherein the first vapor effluent stream produced in (b) has a pressure ranging from about 108 kPaa (1 psig) to about 1480 kPaa (200 psig).

5. The process of claim 1 wherein the first vapor effluent stream produced in (b) has a pressure ranging from about 108 kPaa (1 psig) to about 791 kPaa (100 psig).

6. The process of claim 1 wherein the first vapor effluent stream produced in (b) has a pressure ranging from about 136 kPaa (5 psig) to about 377 kPaa (40 psig).

7. The process of claim 1 wherein the first vapor effluent stream produced in (b) has a temperature ranging from about 20°

C. (68°

F.) to about 54°

C. (130°

F.).

8. The process of claim 1 wherein the first vapor effluent stream produced in (b) has a temperature ranging from about about 32°

C. (90°

F.) to about 43°

C. (110°

F.).

9. The process of claim 1 wherein the condensed liquid effluent stream and the residual vapor effluent stream produced in (c) have a pressure ranging from about 446 kPaa (50 psig) to about 2514 kPaa (350 psig).

10. The process of claim 1 wherein the coudensed liquid effluent stream and the residual vapor effluent stream produced in (c) have a pressure ranging fran, about 791 kPaa (100 psig) to about 2100 kPaa (290 psig).

11. The process of claim 1 wherein the condensed liquid effluent stream and the residual vapor effluent stream produced in (c) have a pressure ranging from about 1066 kPaa (140 psig) to about 1342 kPaa (180 psig).

12. The process of claim 1 wherein the condensed liquid effluent stream produced in (c) comprises up to about 20 wt. % aromatics.

13. The process of claim 1 wherein the condensed liquid effluent stream produced in (c) comprises up to about 10 wt. % aromatics.

14. The process of claim 1 wherein the condensed liquid effluent stream produced in (c) comprises up to about 1 wt. % aromatics.

15. The process of claim 1 wherein the condensed liquid effluent stream produced in (c) comprises up to about 10 wt. % benzene.

16. The process of claim 1 wherein the condensed liquid effluent stream produced in (c) comprises up to about 5 wt. % benzene.

17. The process of claim 1 wherein the condensed liquid effluent stream produced in (c) comprises up to about 0.5 wt. % benzene.

18. The process of claim 1 wherein the condensed liquid effluent stream produced in (c) comprises at least about 1 wt. % of said at least one oxygenate.

19. The process of claim 1 wherein the condensed liquid effluent stream produced in (a) comprises at least about 10 wt. % of said at least one oxygenate.

20. The process of claim 1 wherein the condensed liquid effluent stream produced in (c) comprises at least about 20 wt. % of said at least one oxygenate.

21. The process of claim 1 wherein the vapor product stream in (a) further comprises C₂ to C₆ carbonyls, and the condensed liquid effluent stream produced in (c) comprises at least 0.10 wt. % C₂ to C₆ carbonyls.

22. The process of claim 1 wherein the vapor product steam in (a) further comprises C₂ to C₆ carbonyls, and the condensed liquid effluent stream produced in (c) comprises at least 5 wt. % C₂ to C₆ carbonyls.

23. The process of claim 1 wherein the vapor product stream in (a) further comprises C₂ to C₆ carbonyls, and the condensed liquid effluent stream produced in (c) comprises at least 10 wt. % C₂ to C₆ carbonyls.

24. The process of claim 1 wherein (c) comprises compressing the first vapor affluent stream, cooling the compressed first vapor effluent stream to form a condensate and providing the condensate to a vessel to separate the condensed liquid effluent stream from the residual vapor effluent stream.

25. The process of claim 1 wherein (c) comprises compressing the first vapor effluent stream;

cooling the compressed first vapor effluent stream to produce a first condensed liquid effluent steam and a first residual vapor effluent stream;

compressing the first residual vapor effluent stream and cooling the compressed first residual vapor effluent stream to produce a second condensed liquid effluent stream and a second residual vapor effluent stream and, further wherein at least a portion of the condensed liquid effluent stream in (d) is selected from the group consisting of the first condensed liquid effluent stream, the second condensed liquid effluent stream and mixtures thereof.

26. The process of claim 1 wherein the liquid water-containing stream in (d) comprises at least 90 wt. % water.

27. The process of claim 1 wherein the liquid water-containing stream in (d) comprises at least 95 wt. % water.

28. The process of claim 1 wherein said organic phase in (d) comprises up to about 95 wt. % C₅+ hydrocarbons.

29. The process of claim 1 wherein said organic phase in (d) comprises up to about 75 wt. % C₅+ hydrocarbons.

30. The process of claim 1 wherein said organic phase in (d) comprises up to about 40 wt. % C₂ to C₆ carbonyls.

31. The process of claim 1 wherein said organic phase in (d) comprises up to about 25 wt. % C₂ to C₆ carbonyls.

32. The process of claim 1 wherein said contacting (d) is conducted within said liquid-liquid contacting device at a pressure of from about 170 kPaa (10 psig) to about 2514 kPaa (350 psig), and a temperature of from about 1°

C. (34°

F.) to about 54°

C. (130°

F.).

33. The process of claim 1 wherein said contacting (d) is conducted within said liquid-liquid contacting device at a pressure of from about 446 kPaa (50 psig) to about 1480 kPaa (200 psig), and a temperature of from about 21°

C. (70°

F.) to about 43°

C. (110°

F.).

34. The process of claim 1 wherein the contacting (d) comprises feeding the liquid water-containing stream to the liquid-liquid contacting device at a first rate and feeding the condensed liquid effluent stream to the liquid-liquid contacting device at a second rate, wherein the weight ratio of the second rate to the first rate ranges from about 0.1 to about 10.

35. The process of claim 34 wherein the weight ratio of the second rate to the first rate ranges from about 0.2 to about 2.

36. The process of claim 34 wherein the weight ratio of the second rate to the first rate ranges from about 0.3 to about 1.4.

37. The process of claim 34 wherein the weight ratio of the second rate to the first rate ranges from about 0.6 to about 1.2.

38. The process of claim 34 wherein said at least one oxygenated hydrocarbon includes methanol and the weight ratio of methanol in the second rate to the first rate ranges from about 0.1 to about 1.

39. The process of claim 38 wherein the weight ratio of methanol in the second rate to the first rate ranges from about 0.2 to about 0.7.

40. The process of claim 38 wherein the weight ratio of methanol in the second rate to the first rate ranges from about 0.3 to about 0.6.

41. The process of claim 1 further comprising fractionating the aqueous phase into a water-rich fraction and a fraction rich in said at least one oxygenate.

42. The process of claim 41 wherein at least a portion of said liquid water-containing stream in (d) is at least a portion of said water-rich fraction.

43. The process of claim 41 wherein at least part of said fraction rich in said at least one oxygenate is recycled to said oxygenate to olefin conversion reaction.

44. The process of claim 1 further comprising exposing said condensed liquid effluent stream produced in (c) to one or more reductions in pressure to form a flash liquid effluent stream, wherein said flash liquid effluent stream is provided as the portion of the condensed liquid effluent stream for contacting (d).

45. The process of claim 44 wherein the flash liquid effluent stream comprises up to about 20 wt. % aromatics.

46. A process for producing olefins comprising:

(a) providing a vapor product stream from an oxygenate to olefin reaction comprising C₂ to C₄ olefins, C₅+ hydrocarbons, at least one oxygenate and water;

(b) cooling the vapor product stream to remove water therefrom and produce a first vapor effluent stream;

(c) compressing and cooling the first vapor effluent stream to produce a second effluent stream that is at least partially in the vapor state;

(d) washing at least part of the second effluent stream with a liquid alcohol-containing stream to remove at least a portion of at least one oxygenate from the second effluent stream in a wash liquid effluent stream, and produce a wash vapor effluent stream comprising C₂ to C₄ olefins, the wash liquid effluent stream further comprising C₅+ hydrocarbons and alcohol contained in the liquid alcohol-containing stream; and

(e) contacting at least a portion of the wash liquid effluent steam with a liquid water-containing stream in a liquid-liquid contacting device to at least partially separate said wash liquid effluent stream, or portion thereof, into an aqueous phase rich in said at least one oxygenate and alcohol from the liquid alcohol-containing stream, and an organic phase rich in said C₅+ hydrocarbons.

47. The process of claim 46 wherein said liquid alcohol-containing stream comprises at least one alcohol from the group consisting of methanol and ethanol.

48. The process of claim 46 wherein said liquid alcohol-containing stream comprises methanol.

49. The process of claim 46 wherein the wash liquid effluent stream produced in (d) comprises up to about 20 wt. % aromatics.

50. The process of claim 46 wherein the wash liquid effluent stream produced in (d) comprises up to about 10 wt. % aromatics.

51. The process of claim 46 wherein the wash liquid effluent stream produced in (d) comprises up to about 1 wt. % aromatics.

52. The process of claim 46 wherein the wash liquid effluent stream produced in (d) comprises at least about 1 wt. % of said at least one oxygenate.

53. The process of claim 46 wherein the wash liquid effluent stream produced in (d) comprises at least about 10 wt. % of said at least one oxygenate.

54. The process of claim 46 wherein the wash liquid effluent stream produced in (d) comprises at least about 20 wt. % of said at least one oxygenate.

55. The process of claim 46 wherein the wash liquid effluent stream produced in (d) comprises at least about 10 wt. % alcohol contained in the liquid alcohol-containing stream.

56. The process of claim 46 wherein the wash liquid effluent stream produced in (d) comprises at least about 20 wt. % alcohol contained in the liquid alcohol-containing stream.

57. The process of claim 46 wherein the liquid water-containing stream in (e) comprises at least 90 wt. % water.

58. The process of claim 46 wherein the liquid water-containing stream in (e) comprises at least 95 wt. % water.

59. The process of claim 46 wherein said organic phase in (e) comprises up to about 95 wt. % C₅+ hydrocarbons.

60. The process of claim 46 wherein said organic phase in (e) comprises up to about 75 wt. % C₅+ hydrocarbons.

61. The process of claim 46 wherein said organic phase in (e) comprises up to about 40 wt. % C₂ to C₆ carbonyls.

62. The process of claim 46 wherein said organic phase in (e) comprises up to about 25 wt. % C₂ to C₆ carbonyls.

63. The process of claim 46 wherein said contacting (e) is conducted at a pressure of from about 170 kPaa (10 psig) to about 2514 kPaa (350 psig), and a temperature of from about 1°

C. (34°

F.) to about 54°

C. (130°

F.).

64. The process of claim 46 wherein said contacting (e) is conducted within said liquid-liquid contacting device at a pressure of from about 446 kPaa (50 psig) to about 1480 kPaa (200 psig), and a temperature of from about 21°

C. (70°

F.) to about 43°

C. (110°

F.).

65. The process of claim 46 further comprising exposing said wash liquid effluent stream produced in (d) to one or more reductions in pressure to form a wash flash liquid effluent stream, wherein said wash flash liquid effluent stream is provided as the portion of the wash liquid effluent stream for contacting (e).

66. The process of claim 65 wherein the wash flash liquid effluent stream comprises up to about 20 wt. % aromatics.

67. The process of claim 65 wherein the wash flash liquid effluent stream comprises at least about 30 wt. % alcohol contained in the liquid alcohol-containing stream.

68. The process of claim 46 wherein (c) comprises compressing the first vapor effluent stream;

cooling the compressed first vapor effluent stream to produce a first condensed liquid effluent stream and a first residual vapor effluent stream;

compressing the first residual vapor effluent stream; and

cooling the compressed first residual vapor effluent stream to produce a second residual vapor effluent stream that is at least partially in the vapor state, said second residual vapor effluent stream being provided for said washing (d).

69. The process of claim 46 further comprising fractionating the aqueous phase into a water-rich fraction and a fraction rich in said at least one oxygenate.

70. The process of claim 46 wherein at least a portion of said liquid water-containing stream in (e) is at least a portion of said water-rich fraction.

71. A process for producing olefins comprising:

(a) providing a vapor product stream from an oxygenate to olefin reaction comprising C₂ to C₄ olefins, C₅+ hydrocarbons, at least one oxygenate and water;

(b) cooling the vapor product stream to remove water therefrom and produce a first vapor effluent stream;

(c) compressing and cooling the first vapor effluent stream to produce a condensed liquid effluent stream comprising C₅+ hydrocarbons and at least one oxygenate, and a residual vapor effluent steam comprising C₂ to C₄ olefins, and;

(d) washing at least part of the residual vapor effluent stream with a liquid alcohol-containing stream to produce a wash vapor effluent stream comprising C₂ to C₄ olefins, and a wash liquid effluent stream comprising said at least one oxygenated hydrocarbon and said C₅+ hydrocarbons; and

(e) contacting at least a portion of the condensed liquid effluent stream produced in (c) and at least a portion of the wash liquid effluent stream produced in (d) with a liquid water-containing stream in a liquid-liquid contacting device to at least partially separate said condensed liquid effluent stream produced in (c) and the wash liquid effluent stream produced in (d), or portions thereof;

into an aqueous phase rich in said at least one oxygenate and alcohol contained in the liquid alcohol containing stream, and an organic phase rich in said C₅+ hydrocarbons.

72. The process of claim 71 wherein said liquid alcohol-containing stream comprises methanol and/or ethanol.

73. The process of claim 71 wherein said liquid alcohol-containing stream comprises methanol.

74. The process of claim 71 wherein the wash liquid effluent stream produced in (d) comprises up to about 20 wt. % aromatics.

75. The process of claim 71 wherein the wash liquid effluent stream produced in (d) comprises up to about 10 wt. % aromatics.

76. The process of claim 71 wherein the wash liquid effluent stream produced in (d) comprises up to about 1 wt. % aromatics.

77. The process of claim 71 wherein the wash liquid effluent stream produced in (d) comprises at least about 1 wt. % of said at least one oxygenate.

78. The process of claim 71 wherein the wash liquid effluent stream produced in (d) comprises at least about 10 wt. % of said at least one oxygenate.

79. The process of claim 71 wherein the wash liquid effluent stream produced in (d) comprises at least about 20 wt. % of said at least one oxygenate.

80. The process of claim 71 wherein the wash liquid effluent stream produced in (d) comprises at least about 10 wt. % alcohol contained in the liquid alcohol-containing stream.

81. The process of claim 71 wherein the wash liquid effluent stream produced in (d) comprises at least about 20 wt. % alcohol contained in the liquid alcohol-containing stream.

82. The process of claim 71 further comprising exposing said wash liquid effluent stream produced in (d) to one or more reductions in pressure to form a wash flash liquid effluent stream, wherein said wash flash liquid effluent stream is provided as the portion of the wash liquid effluent stream for contacting (e).

83. The process of claim 82 wherein the wash flash liquid effluent stream comprises up to about 20 wt. % aromatics.

84. The process of claim 82 wherein the wash flash liquid effluent stream comprises at least about 20 wt. % alcohol contained in the liquid alcohol-containing stream.

85. The process of claim 82 wherein the wash flash liquid effluent stream comprises at least about 30 wt. % alcohol contained in the liquid alcohol-containing stream.

86. The process of claim 71 wherein the liquid water-containing stream in (e) comprises at least 90 wt. % water.

87. The process of claim 71 wherein the liquid water-containing stream in (e) comprises at least 95 wt. % water.

88. The process of claim 71 wherein said organic phase in (e) comprises up to about 95 wt. % C₅+ hydrocarbons.

89. The process of claim 71 wherein said organic phase in (e) comprises up to about 75 wt. % C₅+ hydrocarbons.

90. The process of claim 71 wherein said organic phase in (e) comprises up to about 40 wt. % C₂ to C₆ carbonyls.

91. The process of claim 71 wherein said organic phase in (e) comprises up to about 25 wt. % C₂ to C₆ carbonyls.

92. The process of claim 71 wherein said contacting (e) is conducted at a pressure of from about 170 kPaa (10 psig) to about 2514 kPaa (350 psig), and a temperature of from about 1°

C. (34°

F.) to about 54°

C. (130°

F.).

93. The process of claim 71 wherein said contacting (e) is conducted within said liquid-liquid contacting device at a pressure of from about 446 kPaa (50 psig) to about 1480 kPaa (200 psig), and a temperature of from about 21°

C. (70°

F.) to about 43°

C. (110°

F.).

94. The process of claim 71 further comprising fractionating the aqueous phase into a water-rich fraction and a fraction rich in said at least one oxygenate.

95. The process of claim 94 wherein at least a portion of said liquid water-containing stream in (e) is at least a portion of said water-rich fraction.

96. The process of claim 71 wherein said condensed liquid effluent stream and said wash liquid effluent stream, or portions thereof, are combined, and said combined stream, or portion thereof, is provided for contacting (e).

97. The process of claim 71 wherein said condensed liquid effluent stream and said wash liquid effluent stream, or portions thereof, are combined, and said combined stream, or portion thereof, is exposed to one or more reductions in pressure to form a flash liquid effluent stream, wherein said flash liquid effluent stream is provided as the portion of the wash liquid effluent stream for contacting (e).

98. The process of claim 71 wherein (c) comprises compressing the first vapor effluent stream;

cooling the compressed first vapor effluent stream to produce a first condensed liquid effluent steam and a first residual vapor effluent stream;

compressing the first residual vapor effluent stream; and

cooling the compressed first residual vapor effluent stream to produce a second effluent stream that is at least partially in the vapor state, at least part of said second effluent stream being provided for said washing (d).

99. The process of claim 98 wherein said second effluent stream is segregated into a second condensed liquid effluent stream and a second residual vapor effluent stream, said second residual vapor effluent stream being provided for said washing (d).

100. The process of claim 99 wherein said first condensed liquid effluent stream, said second condensed liquid effluent stream or said wash liquid effluent steam, or portions thereof, is exposed to one or more reductions in pressure to form a flash liquid effluent stream, wherein said flash liquid effluent stream is provided as the portion of the condensed liquid effluent stream and wash liquid effluent stream for contacting (e).

101. The process of claim 99 wherein said second condensed liquid effluent stream and said wash liquid effluent stream, or portions thereof, are exposed to a reduction in pressure along with the compressed and cooled first vapor effluent stream to produce a first residual vapor effluent stream and a common first condensed liquid effluent stream and first flash liquid effluent stream, said common first condensed liquid effluent stream and first flash liquid effluent stream being exposed to a further reduction in pressure to produce a second flash liquid effluent stream, and said second flash liquid effluent stream being provided as the portion of the condensed liquid effluent stream and wash liquid effluent stream for contacting (e).