Processes for producing fluorided solid oxides and uses thereof in metallocene-based catalyst systems
Disclosed herein are methods for preparing fluorided solid oxides by contacting an acidic fluorine-containing compound with an inorganic base to form an aqueous mixture having a pH of at least 4, followed by contacting a solid oxide with the aqueous mixture to produce the fluorided solid oxide. Also disclosed are methods for preparing fluorided solid oxides by contacting an acidic fluorine-containing compound with a solid oxide to produce a mixture, followed by contacting the mixture with a inorganic base to produce the fluorided solid oxide at a pH of at least about 4. The fluorided solid oxide can be used as an activator component in a catalyst system for the polymerization of olefins.
1. A fluorided solid oxide comprising:
a silica-coated alumina;
from about 0.5 to about 15 wt. % F; and
from about 0.5 to about 15 wt. % Zn;
wherein the fluorided solid oxide comprises ZnSiF 6 .
2. A catalyst composition comprising a metallocene compound, the fluorided solid oxide of claim 1 , and an optional co-catalyst.
3. The composition of claim 2 , wherein a catalyst activity of the catalyst composition is greater than about 6000 grams of polyethylene per gram of the fluorided solid oxide per hour, under slurry polymerization conditions, with a triisobutylaluminum co-catalyst, using isobutane as a diluent, and with a polymerization temperature of 95° C. and a reactor pressure of 400 psig.
4. An olefin polymerization process, the process comprising:
contacting the catalyst composition of claim 2 with an olefin monomer and an optional olefin comonomer in a polymerization reactor system under polymerization conditions to produce an olefin polymer.
5. The fluorided solid oxide of claim 1 , wherein the fluorided solid oxide comprises from about 2 to about 9 wt. % F, and from about 0.5 to about 5 wt. % Zn.
6. The fluorided solid oxide of claim 1 , wherein the fluorided solid oxide further comprises from about 0.3 to about 1 wt. % B.
7. The fluorided solid oxide of claim 1 , wherein the fluorided solid oxide has:
a total pore volume from about 0.5 to about 2.5 mL/g;
a BET surface area from about 150 to about 700 m 2 /g; and
an average (d50) particle size from about 20 to about 100 microns.
8. The fluorided solid oxide of claim 1 , wherein:
the silica-coated alumina contains from about 25 to about 50 wt. % silica, based on the weight of the silica-coated alumina.
9. The fluorided solid oxide of claim 1 , wherein the fluorided solid oxide comprises from about 3 to about 7 wt. % F, and from about 1 to about 5 wt. % Zn.
10. The fluorided solid oxide of claim 9 , wherein the fluorided solid oxide has:
a total pore volume from about 0.5 to about 2.5 mL/g;
a BET surface area from about 150 to about 700 m 2 /g; and
an average (d50) particle size from about 20 to about 100 microns.
11. The fluorided solid oxide of claim 10 , wherein the silica-coated alumina contains from about 25 to about 50 wt. % silica, based on the weight of the silica-coated alumina.
12. The fluorided solid oxide of claim 1 , wherein the fluorided solid oxide comprises from about 4 to about 10 wt. % ZnSiF 6 .
13. A fluorided solid oxide comprising:
a silica-coated alumina;
from about 0.5 to about 15 wt. % F;
from about 0.5 to about 15 wt. % Zn; and
from about 0.2 to about 1.2 wt. % B.
14. The fluorided solid oxide of claim 13 , wherein the fluorided solid oxide comprises:
from about 2 to about 9 wt. % F; and
from about 0.5 to about 5 wt. % Zn.
15. The fluorided solid oxide of claim 13 , wherein the fluorided solid oxide has:
a total pore volume from about 0.5 to about 2.5 mL/g;
a BET surface area from about 150 to about 700 m 2 /g; and
an average (d50) particle size from about 20 to about 100 microns.
16. The fluorided solid oxide of claim 13 , wherein the fluorided solid oxide comprises Zn(BF 4 ) 2 .
17. The fluorided solid oxide of claim 13 , wherein:
the silica-coated alumina contains from about 25 to about 50 wt. % silica, based on the weight of the silica-coated alumina.
18. A catalyst composition comprising a metallocene compound, the fluorided solid oxide of claim 13 , and an optional co-catalyst.
19. The composition of claim 18 , wherein a catalyst activity of the catalyst composition is greater than about 6000 grams of polyethylene per gram of the fluorided solid oxide per hour, under slurry polymerization conditions, with a triisobutylaluminum co-catalyst, using isobutane as a diluent, and with a polymerization temperature of 95° C. and a reactor pressure of 400 psig.
20. An olefin polymerization process, the process comprising:
contacting the catalyst composition of claim 18 with an olefin monomer and an optional olefin comonomer in a polymerization reactor system under polymerization conditions to produce an olefin polymer.
21. The fluorided solid oxide of claim 13 , wherein the fluorided solid oxide comprises:
from about 3 to about 7 wt. % F;
from about 1 to about 5 wt. % Zn; and
from about 0.3 to about 1 wt. % B.
22. The fluorided solid oxide of claim 21 , wherein the fluorided solid oxide has:
a total pore volume from about 0.5 to about 2.5 mL/g;
a BET surface area from about 150 to about 700 m 2 /g; and
an average (d50) particle size from about 20 to about 100 microns.
23. The fluorided solid oxide of claim 22 , wherein the silica-coated alumina contains from about 25 to about 50 wt. % silica, based on the weight of the silica-coated alumina.
24. The fluorided solid oxide of claim 13 , wherein the fluorided solid oxide comprises from about 4 to about 10 wt. % Zn(BF 4 ) 2 .
25. The fluorided solid oxide of claim 13 , wherein:
the silica-coated alumina contains from about 25 to about 50 wt. % silica, based on the weight of the silica-coated alumina; and
the fluorided solid oxide comprises Zn(BF 4 ) 2 .
26. A fluorided solid oxide comprising:
a silica-coated alumina; and
Zn(BF 4 ) 2 , ZnSiF 6 , or a combination thereof.