Ligands for production of 1-hexene in chromium assisted ethylene oligomerization process

Patent metadata

Field	Value
Publication number	US-11247201-B2
Application number	US-201917292285-A
Country	US
Kind code	B2
Filing date	Nov 11, 2019
Priority date	Nov 12, 2018
Publication date	Feb 15, 2022
Grant date	Feb 15, 2022

Abstract

Catalyst compositions and processes for the oligomerization of ethylene to 1-hexene are described. The catalyst composition includes a triamino bisphospino (NPNPN) ligand system with specific phosphorous and nitrogen ligands. The terminal nitrogen atoms include linear alkyl hydrocarbons that differ in the number of carbon atoms by 3.

First claim

The invention claimed is:

1. A catalyst composition for the oligomerization of ethylene to 1-hexene, the catalyst composition comprising:
a chromium (III) species; and
a ligand having the formula of:

where R 1 and R 2 are the same or different and are selected from the group consisting of (i) C 3 to C 4 non-cyclic aliphatic groups, (ii) C 5 to C 7 aliphatic groups which may be cyclic or non-cyclic, linear or branched, substituted or unsubstituted, and (iii) any combination thereof; and,
wherein n is 0 or 1, and m=n+3.

2. The catalyst composition of claim 1 , wherein R 1 and R 2 are each independently a cyclic hydrocarbon group, a substituted cyclic hydrocarbon group, a linear hydrocarbon group or a branched hydrocarbon group having 1 to 10 carbon atoms.

3. The catalyst composition of claim 2 , wherein R 1 and R 2 are each a cyclohexyl group.

4. The catalyst composition of claim 3 , wherein n is 0, and the ligand has the structure of:

5. The catalyst composition of claim 3 , wherein n is land the ligand has the structure of:

6. The catalyst composition of claim 1 , wherein the composition further comprises an activator or co-catalyst.

7. The catalyst composition of claim 6 , wherein the activator or co-catalyst is a methylaluminoxane compound.

8. The catalyst composition of claim 6 , wherein the activator or co-catalyst is a methyl iso-butyl aluminum oxide compound.

9. The catalyst composition of claim 1 , wherein the chromium (III) species is selected from the group consisting of chromium (III) acetylacetonate, Cr(2,2,6,6,-tetramethyl-3,5-heptadionate) 3 , chromium(III)2-ethylhexanoate, chromium trichloride; tris-tetrahydrofuran, (benzene)tricarbonyl chromium, chromium (III) octanoate and chromium (III) naphthenate.

10. The catalyst composition of claim 1 , wherein one or both of R 1 and R 2 are selected from the group consisting of iso-propyl and tert-butyl.

11. A process to produce 1-hexene from ethylene, the process comprising contacting a reactant stream comprising an olefin source with a solution comprising the catalyst composition of claim 1 to produce a oligomer composition comprising 1-hexene.

12. The process of claim 11 , wherein the solution comprises a solvent.

13. The process of claim 12 , wherein the solvent is a saturated hydrocarbon.

14. The process of claim 13 , wherein the solvent is n-hexane, methylcyclohexane, or a mixture thereof.

15. The process of claim 11 , wherein the oligomer product further comprises 1-octene and a selectivity for 1-hexene is greater than 99%, and a weight ratio of 1-octene to 1-hexene is less than 0.15.

16. The process of claim 15 , wherein the ligand comprises:

17. The process of claim 15 , wherein the solution further comprises an activator or co-catalyst.

18. The process of claim 11 , wherein the catalyst composition comprises the chromium (III) species, an activator or co-catalyst and the ligand has the structure of:

19. The process of claim 11 , wherein the contacting comprises a temperature of 15° C. to 100° C.

20. The process of claim 11 , wherein the contacting comprises a pressure of at least 2 MPa or 2 to 20 MPa.

Assignees

• Sabic Global Technologies Bv

Inventors

• Al-Nezari Abdulaziz
• Vidjayacoumar Balamurugan
• Korobkov Ilia
• Albahily Khalid

Classifications

• C07C2531/34

  of chromium, molybdenum or tungsten · CPC title

• C07C2/36

  as phosphines, arsines, stilbines or bismuthines · CPC title

• B01J31/143 Primary

  of aluminium · CPC title

• B01J31/0265 Primary

  Phosphazenes, oligomers thereof or the corresponding phosphazenium salts (polyphosphazenes per se C07F9/067) · CPC title

• C07C2531/22

  Organic complexes · CPC title