Fluorinated catalyst supports and catalyst systems
Catalyst systems and methods for making and using the same. A method for making a catalyst support includes forming a mixture of a support material and a fluoride donor. The mixture is added to a fluidized bed reactor. The mixture is fluidized to form a fluidized bed while maintaining a flow rate of a fluidizing gas of about 0.1 ft./sec at less than about 370° C. and greater than about 0.35 ft./sec at temperatures greater than about 370° C. The mixture is calcined to decompose the fluoride donor, forming a fluorinated support.
1. A method for making a fluorinated catalyst support, comprising:
forming a mixture of a support material that can be fluorinated and a fluoride donor;
adding the mixture to a fluidized bed reactor;
fluidizing the mixture in the fluidized bed reactor with a fluidizing gas by maintaining a flow rate of the fluidizing gas of about 0.1 ft./sec at less than about 370° C. and greater than about 0.35 ft./sec at temperatures greater than about 370° C.; and
calcining the mixture to decompose the fluoride donor, forming a fluorinated catalyst support.
2. The method of claim 1 , comprising maintaining a ratio of a pressure drop across a distributor plate to a pressure drop across the fluidized bed of greater than about 7%.
3. The method of claim 1 , comprising forming a fluidized bed with a height to diameter ratio of at least about 2.3.
4. The method of claim 1 , comprising increasing a flow rate of the fluidizing gas from about 0.1 ft./sec. to about 0.4 ft./sec starting at a temperature of between about 350° C. and about 370° C.
5. The method of claim 1 , comprising maintaining a filter face velocity of less than about 4 ft./sec.
6. The method of claim 1 , wherein the fluoride donor comprises ammonium hexafluorosilicate, ammonium bifluoride, ammonium tetrafluoroborate, or any combination thereof.
7. The method of claim 1 , further comprising forming a catalyst system by combining a catalyst compound with the fluorinated catalyst support.
8. The method of claim 1 , further comprising:
combining a catalyst compound and an aluminoxane to produce a first mixture; and
adding the fluorinated catalyst support to the first mixture and drying to produce a catalyst system.
9. A catalyst system, comprising:
a catalyst compound including a metal;
a support comprising a fluorinated support, wherein the fluorinated support is generated by heating a mixture of a catalyst support that can be fluorinated and a fluoride donor compound in a fluidized bed reactor that is fluidized by maintaining a flow rate of a fluidizing gas of about 0.1 ft./sec at less than about 370° C. and greater than about 0.35 ft./sec at temperatures greater than about 370° C.; and
an aluminoxane, wherein the aluminoxane is present in an amount of about 10 mmol or less per gram of the support.
10. The catalyst system of claim 9 , wherein the support has a fluoride concentration ranging from about 1 wt. % to about 10 wt. %, based on a weight of the support and an aluminum concentration ranging from about 3 wt. % to about 40 wt. % based on the weight of the support.
11. The catalyst system of claim 9 , wherein the support has a fluoride concentration ranging from about 4 wt. % to about 8 wt. %, based on a weight of the support and an aluminum concentration ranging from about 20 wt. % to about 40 wt. % based on the weight of the support.
12. The catalyst system of claim 9 , wherein the support has a fluoride concentration ranging from about 2 wt. % to about 4 wt. %, based on a weight of the support and an aluminum concentration ranging from about 3 wt. % to about 10 wt. % based on the weight of the support.
13. The catalyst system according to claim 9 , wherein a concentration of the metal from the catalyst compound ranges from about 0.2 wt. % to about 1.3 wt. %, based on a total weight of the catalyst system.
14. The catalyst system according to claim 9 , wherein the aluminoxane is present in an amount of about 4 mmol or less per gram of the support.
15. The catalyst system according to claim 9 , wherein the aluminoxane is present in an amount of about 2.7 mmol or less per gram of the support.
16. The catalyst system according to claim 9 , wherein the aluminoxane comprises methylaluminoxane, modified methylaluminoxane, or a combination thereof.
17. The catalyst system according to claim 9 , wherein the support further comprises silica.
18. The catalyst system according to claim 9 , wherein the catalyst compound comprises a metallocene catalyst.
19. The catalyst system of claim 18 , wherein the metallocene catalyst has the formula:
Cp A Cp B MX n or Cp A (A)Cp B MX n ,
wherein M is a Group 4, 5 or 6 atom; Cp A and Cp B are each bound to M and are independently selected from the group consisting of cyclopentadienyl ligands, substituted cyclopentadienyl ligands, ligands isolobal to cyclopentadienyl and substituted ligands isolobal to cyclopentadienyl; (A) is a divalent bridging group bound to both Cp A and Cp B selected from the group consisting of divalent C 1 to C 20 hydrocarbyls and C 1 to C 20 heteroatom containing hydrocarbonyls, wherein the heteroatom containing hydrocarbonyls comprise from one to three heteroatoms; X is a leaving group selected from the group consisting of chloride ions, bromide ions, C 1 to C 10 alkyls, and C 2 to C 12 alkenyls, carboxylates, acetylacetonates, and alkoxides; and n is an integer from 1 to 4.