Catalyst systems suitable for the tetramerization of ethylene and methods of using the same

Patent metadata

Field	Value
Publication number	US-12364976-B2
Application number	US-202318178808-A
Country	US
Kind code	B2
Filing date	Mar 6, 2023
Priority date	Mar 6, 2023
Publication date	Jul 22, 2025
Grant date	Jul 22, 2025

Abstract

Catalyst systems suitable for tetramerizing ethylene to form 1-octene may include a catalyst including a chromium compound coordinated with a ligand and a co-catalyst including an organoaluminum compound. The ligand may have a chemical structure according to Formula (1), wherein R1 is a (C3-C20) substituted or unsubstituted hydrocarbyl group; R2, R3, R4, and R5 are independently chosen from (C1-C50) hydrocarbyl groups; and R1 and N are in a cis configuration.

First claim

The invention claimed is:

1. A catalyst system suitable for tetramerizing ethylene to form 1-octene, the catalyst system comprising:
a catalyst comprising a chromium compound coordinated with a ligand; and
a co-catalyst comprising an organoaluminum compound,
wherein:
the ligand has the chemical structure:

R 1 is a (C 3 -C 20 ) substituted or unsubstituted hydrocarbyl group;
R 2 , R 3 , R 4 , and R 5 are independently chosen from (C 1 -C 50 ) hydrocarbyl groups; and
R 1 and N are in a cis configuration.

2. The catalyst system of claim 1 , wherein R 1 is a (C 3 -C 20 ) unsubstituted hydrocarbyl group.

3. The catalyst system of claim 1 , wherein R 1 is a (C 3 -C 20 ) alkyl group.

4. The catalyst system of claim 1 , wherein R 1 is a (C 3 -C 20 ) substituted hydrocarbyl group comprising one or more heteroatoms.

5. The catalyst system of claim 4 , wherein the one or more heteroatoms are chosen from boron, nitrogen, oxygen, fluorine, phosphorous, silicon, sulfur, chlorine, and combinations thereof.

6. The catalyst system of claim 1 , wherein R 2 , R 3 , R 4 , and R 5 are independently chosen from (C 1 -C 50 ) cyclohydrocarbyl groups.

7. The catalyst system of claim 1 , wherein R 2 , R 3 , R 4 , and R 5 are independently chosen from (C 4 -C 50 ) aryl groups.

8. The catalyst system of claim 1 , wherein each of R 2 , R 3 , R 4 , and R 5 are phenyl groups.

9. The catalyst system of claim 1 , wherein the ligand is chosen from cis-1-bis(diphenylphosphino)amino-4-butylcyclohexane, or cis-1-bis(diphenylphosphino)amino-4-isopropylcyclohexane, or cis-1-bis(diphenylphosphino)amino-4-dodecylcyclohexane.

10. The catalyst system of claim 1 , wherein the catalyst system further comprises an aliphatic solvent.

11. The catalyst system of claim 10 , wherein the aliphatic solvent comprises one or more of alkanes and cycloalkanes.

12. The catalyst system of claim 1 , wherein the chromium compound comprises one or more of an organic chromium salt, an inorganic chromium salt, a chromium coordination, and a chromium organometallic complex.

13. The catalyst system of claim 1 , wherein the chromium compound is chosen from one or more of chromium trichloride tris-tetrahydrofuran complex, (benzene)tricarbonyl chromium, chromium (III) octanoate, chromium (III) acetylacetonoate, chromium hexacarbonyl, tris(2,2,6,6-tetramethyl-3,5-heptanedionato) chromium (III), and chromium (III) 2-ethylhexanoate.

14. The catalyst system of claim 1 , wherein a molar ratio of the ligand to the chromium compound is from 1.0 to 2.0.

15. The catalyst system of claim 1 , wherein the organoaluminum compound has a structure:

wherein R 6 , R 7 , and R 8 are each selected from the group consisting of a hydrogen atom and an unsubstituted (C 1 -C 20 ) linear or branched alkyl group.

16. The catalyst system of claim 1 , wherein the organoaluminum compound is chosen from one or more of trimethylaluminium, triethylaluminum, tripropylaluminum, tri-iso-butylaluminum, diisobutylaluminium hydride, trihexylaluminum, tri-n-octylaluminium, methylaluminium dichloride, ethylaluminium dichloride, dimethylaluminium chloride, diethylaluminium chloride, aluminium isopropoxide, ethylaluminiumsesquichloride, methylaluminiumsesquichloride, methylaluminoxane, ethylaluminoxane, and modified methylaluminoxane.

17. The catalyst system of claim 1 , wherein a molar ratio of the organoaluminum compound to the chromium compound is from 100 to 5000.

18. A method for tetramerizing ethylene to form 1-octene, the method comprising contacting ethylene with a catalyst system to form a product comprising 1-octene, wherein the catalyst system is the catalyst system of claim 1 .

19. The method of claim 18 , wherein the 1-octene is formed at a pressure of from 5 bar to 120 bar.

20. The method of claim 18 , wherein the 1-octene is formed at a temperature of from 20° C. to 130° C.

Assignees

• Saudi Arabian Oil Co

Inventors

• Lin Sibo
• Wong Dana Amber
• Ghosh Yagnaseni
• Khawaji Motaz
• Xu Wei
• Elanany Mohamed

Classifications

• C07C2531/18

  containing nitrogen, phosphorus, arsenic or antimony · CPC title

• C07C2531/14

  of aluminium or boron · CPC title

• B01J2531/62

  Chromium · CPC title

• B01J2231/20

  Olefin oligomerisation or telomerisation · CPC title

• C07C11/02

  Alkenes · CPC title