Olefin conversion process

Patent metadata

Field	Value
Publication number	US-9598331-B2
Application number	US-201414548509-A
Country	US
Kind code	B2
Filing date	Nov 20, 2014
Priority date	Nov 20, 2013
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

Processes for the production of high purity alpha olefins from a mixture of olefins are disclosed. The processes may include: contacting propylene and a hydrocarbon mixture comprising a mixture of olefins having a carbon number n with a first metathesis catalyst to form a metathesis product comprising a beta-olefin having a carbon number n+1, an alpha-olefin having a carbon number n−1, as well as any unreacted propylene and olefins having a carbon number n. The metathesis product may be fractionated to recover a fraction comprising the beta-olefin having a carbon number n+1. Ethylene and the fraction comprising the beta-olefin having a carbon number n+1 may then be contacted with a second metathesis catalyst to form a second metathesis product comprising an alpha-olefin having a carbon number n and propylene, which may be fractionated to form a propylene fraction and a fraction comprising the alpha olefin having a carbon number n.

First claim

What is claimed:

1. A process for the production of olefins, the process comprising:
(a) contacting propylene and a hydrocarbon mixture comprising a mixture of olefins having a carbon number n with a first metathesis catalyst to form a metathesis product comprising a beta-olefin having a carbon number n+1, an alpha-olefin having a carbon number n−1, as well as any unreacted propylene and olefins having a carbon number n;
(b) fractionating the metathesis product to recover a fraction comprising the beta-olefin having a carbon number n+1;
(c) contacting ethylene and the fraction comprising the beta-olefin having a carbon number n+1 with a second metathesis catalyst to form a second metathesis product comprising an alpha-olefin having a carbon number n and propylene; and
(d) fractionating the second metathesis product to form a propylene fraction and a fraction comprising the alpha olefin having a carbon number n, wherein n is selected from the range of 4 to about 8.

2. The process of claim 1 , wherein the hydrocarbon mixture comprises C4 olefins, and the alpha olefin having a carbon number n is 1-butene.

3. The process of claim 1 , wherein the hydrocarbon mixture comprises C5 olefins, and the alpha olefin having a carbon number n is 1-pentene.

4. The process of claim 1 , wherein the hydrocarbon mixture comprises C6 olefins, and the alpha olefin having a carbon number n is 1-hexene.

5. The process of claim 1 , wherein the hydrocarbon mixture comprises C7 olefins, and the alpha olefin having a carbon number n is 1-heptene.

6. The process of claim 1 , wherein the hydrocarbon mixture comprises C8 olefins, and the alpha olefin having a carbon number n is 1-octene.

7. A process for producing high purity 1-butene, the process comprising:
contacting a hydrocarbon mixture comprising linear butenes with an isomerization catalyst to form an isomerization product comprising 2-butenes and 1-butenes;
contacting propylene and the isomerization product with a first metathesis catalyst to form a first metathesis product comprising 2-pentene, propylene unreacted butenes, ethylene and 3-hexene;
fractionating the first metathesis product to recover an ethylene fraction, a propylene fraction, a butene fraction, and a 2-pentene fraction;
contacting the 2-pentene fraction and ethylene with a second metathesis catalyst, which may be the same or different than the first metathesis catalyst, to form a metathesis effluent comprising ethylene, propylene, 1-butene, and any unreacted 2-pentene; and
fractionating the metathesis effluent to recover a 1-butene fraction, a C3− fraction, and a C5+ fraction.

8. The process of claim 7 , further comprising feeding the C3− fraction and the first metathesis product to a common fractionation system.

9. The process of claim 7 , further comprising recycling the C5+ fraction for continued conversion over the second metathesis catalyst.

10. The process of claim 7 , further comprising recycling the butene fraction for continued conversion over the isomerization catalyst and the first metathesis catalyst.

11. A process for producing high purity 1-hexene, the process comprising:
isomerizing and metathesizing a mixed C4 olefin stream comprising 1-butene and 2-butene to produce a first reaction product comprising ethylene, propylene, unreacted butenes, 2-pentene, and 3-hexene;
isomerizing and metathesizing a mixed C5 olefin stream comprising 1-pentene and 2-pentene to produce a second reaction product comprising ethylene, propylene, n-butenes, unreacted pentenes, 3-hexene, 3-heptene, 2-hexene, and 4-octene;
isomerizing and metathesizing propylene and a mixed C6 olefin stream comprising 1-hexene, 2-hexene, and 3-hexene to produce a third reaction product comprising ethylene, n-butenes, n-pentenes, and 2-heptene;
fractionating the first, second, and third reaction products in a common fractionation system to recover an ethylene fraction, a propylene fraction, a butene fraction, a pentene fraction, a hexene fraction, and a heptene fraction comprising 2-heptene;
metathesizing ethylene and the 2-heptene in the heptene fraction to form a metathesis product comprising propylene, 1-hexene, and any unreacted ethylene and 2-heptene; and
fractionating the metathesis product to recover an C5− fraction, a 1-hexene product fraction, and a C7+ fraction.

12. The process of claim 11 , further comprising feeding the C5− fraction to the common fractionation system.

13. The process of claim 11 , further comprising recycling the butene fraction for continued conversion along with the mixed C4 olefin stream.

14. The process of claim 11 , further comprising using at least a portion of the pentene fraction as the mixed C5 olefin stream.

15. The process of claim 11 , further comprising using at least a portion of the hexene fraction as the mixed C6 olefin stream.

16. A process for producing high purity 1-octene, the process comprising:
isomerizing and metathesizing a mixed C4 olefin stream comprising 1-butene and 2-butene to produce a first reaction product comprising ethylene, propylene, unreacted butenes, 2-pentene, and 3-hexene;
isomerizing and metathesizing a mixed C5 olefin stream comprising 1-pentene and 2-pentene to produce a second reaction product comprising ethylene, propylene, n-butenes, unreacted pentenes, 3-hexene, 3-heptene, 2-hexene, and 4-octene;
isomerizing and metathesizing propylene and a mixed C6 olefin stream comprising 1-hexene, 2-hexene, and 3-hexene to produce a third reaction product comprising ethylene, n-butenes, n-pentenes, and 2-heptene;
isomerizing and metathesizing propylene and a mixed C7 olefin stream comprising 1-heptene, 2-heptene, and 3-heptene to produce a fourth reaction product comprising ethylene, n-butenes, n-pentenes, n-hexenes, and 2-octene;
isomerizing and metathesizing propylene and a mixed C8 olefin stream comprising 1-octene, 2-octene, 3-octene, and 4-octene to produce a fifth reaction product comprising ethylene, n-butenes, n-pentenes, n-hexenes, and 2-nonene;
fractionating the first, second, third, fourth, and fifth reaction products in a common fractionation system to recover an ethylene fraction, a propylene fraction, a butene fraction, a pentene fraction, a hexene fraction, a heptene fraction, an octene fraction, and a nonene fraction comprising 2-nonene;
metathesizing ethylene and the 2-nonene in the nonene fraction to form a metathesis product comprising propylene, 1-octene, and any unreacted ethylene and 2-nonene; and
fractionating the metathesis product to recover an C7− fraction, a 1-octene product fraction, and a C9+ fraction.

17. The process of claim 16 , further comprising feeding the C7− fraction to the common fractionation system.

18. The process of claim 16 , further comprising recycling the butene fraction for continued conversion along with the mixed C4 olefin stream.

19. The process of claim 16 , further comprising using at least a portion of the pentene fraction as the mixed C5 olefin stream.

20. The process of claim 16 , further comprising using at least a portion of the hexene fraction as the mixed C6 olefin stream.

21. The process of claim 16 , further comprising using at least a portion of the heptene fraction as the mixed C7 olefin stream.

22. The process of claim 16 , further comprising using at least a portion of the octene fraction as the mixed C8 olefin stream.

Assignees

• Lummus Technology Inc

Inventors

• Ramachandran Bala
• Choi Sukwon

Classifications

• B01J2219/00006

  Large-scale industrial plants · CPC title

• C07C6/04 Primary

  at a carbon-to-carbon double bond · CPC title

• B01J8/0453

  the beds being superimposed one above the other · CPC title

• C07C11/08

  with four carbon atoms · CPC title

• B01J2208/025

  Two or more types of catalyst · CPC title