Oligomerization of alpha olefins using metallocene-SSA catalyst systems and use of the resultant polyalphaolefins to prepare lubricant blends

Patent metadata

Field	Value
Publication number	US-9745230-B2
Application number	US-201615092659-A
Country	US
Kind code	B2
Filing date	Apr 7, 2016
Priority date	Jun 16, 2009
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

Methods for making alpha olefin oligomers and polyalphaolefins include a step of contacting a C 4 to C 20 alpha olefin monomer and a catalyst system containing a metallocene, a first activator comprising a solid oxide chemically-treated with an electron withdrawing anion, and a second activator comprising an organoaluminum compound. The alpha olefin oligomers and polyalphaolefins prepared with these catalyst systems can have a high viscosity index combined with a low pour point, making them particularly useful in lubricant compositions and as viscosity modifiers.

First claim

What is claimed:

1. An oligomerization method comprising:
a) contacting an alpha olefin monomer and a catalyst system, wherein the alpha olefin monomer comprises at least 80 weight percent of a C 6 to C 16 normal alpha olefin, and wherein the catalyst system comprising comprises:
1) a metallocene,
2) a first activator comprising a solid oxide chemically-treated with an electron withdrawing anion, and
3) a second activator comprising an organoaluminum compound having a formula: Al(X 10 ) n (X 11 ) 3-n , wherein X 10 is independently a C 1 to C 20 hydrocarbyl, X 11 is independently a halide, a hydride, or a C 1 to C 20 hydrocarboxide, and n is a number from 1 to 3;
wherein the catalyst system is devoid of added aluminoxane;

b) forming an oligomer product in an oligomerization reactor under oligomerization conditions, wherein the oligomer product comprises dimers, trimers, and higher oligomers, wherein the oligomer product has a pour point less than 0° C.;
c) separating an effluent of the oligomerization reactor comprising the oligomer product to provide a heavy oligomer product, wherein at least a portion of the alpha olefin monomer, dimers, or trimers are removed from the effluent of the oligomerization reactor to form the heavy oligomer product; wherein:
the heavy oligomer product comprises less than 0.2 weight % alpha olefin monomer, less than 0.5 weight % dimers, and at least 88 weight % higher oligomers, based upon the total weight of the heavy oligomer product; and
the heavy oligomer product has a 100° C. kinematic viscosity from 15 cSt to 250 cSt.

2. The oligomerization method of claim 1 , wherein the solid oxide chemically-treated with an electron withdrawing anion comprises a fluorided solid oxide.

3. The oligomerization method of claim 1 , wherein the solid oxide chemically-treated with an electron withdrawing anion comprises a sulfated solid oxide.

4. The oligomerization method of claim 1 , wherein the second activator comprises a trialkylaluminum, an alkylaluminum sesquihalide, an alkylaluminum halide, or any combination thereof.

5. The oligomerization method of claim 1 , wherein:
the alpha olefin monomer comprises a C 6 to C 14 normal alpha olefin;
the solid oxide chemically-treated with an electron withdrawing anion comprises fluorided alumina, chlorided alumina, sulfated alumina, fluorided silica-alumina, or any combination thereof; and
the second activator comprises a trialkylaluminum.

6. The oligomerization method of claim 1 , wherein
an aluminum of the organoaluminum compound to metal of the metallocene (Al:metal) molar ratio ranges from 1:1 to 10,000:1;
a first activator to metallocene weight ratio ranges from 1:1 to 100,000:1; and
an alpha olefin monomer to metallocene weight ratio ranges from 100:1 to 10,000,000:1.

7. The oligomerization method of claim 1 , wherein the alpha olefin monomer and catalyst system are contacted by the steps of:
(1) contacting the alpha olefin monomer and the second activator to form a mixture; and
(2) contacting the mixture with the first activator and the metallocene in any order.

8. The oligomerization method of claim 1 , wherein:
the oligomerization conditions comprise a temperature ranging from 50° C. to 165° C.;
at least 80 weight % of the alpha olefin monomer is converted to the oligomer product; and
the oligomer product comprises at least 75 weight % higher oligomers.

9. The oligomerization method of claim 1 , wherein:
the metallocene has the formula (η 5 -cycloalkadienyl) 2 M 3 X 9 2 , wherein
i) the two (η 5 -cycloalkadienyl) ligands are linked by a linking group having the structure >CR 1 R 2 , >SiR 3 R 4 , or —CR 5 R 6 CR 7 R 8 —, wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 are selected independently from hydrogen or a saturated or unsaturated C 1 -C 20 hydrocarbyl group,
ii) each η 5 -cycloalkadienyl ligand independently is a substituted or an unsubstituted cyclopentadienyl ligand, a substituted or an unsubstituted indenyl ligand, or a substituted or an unsubstituted fluorenyl ligand, wherein each non-linking substituent independently is a halide, a C 1 to C 20 hydrocarbyl group, or a C 1 to C 20 hydrocarboxy group,
iii) X 9 is a halide, a C 1 -C 20 hydrocarbyl group, or a C 1 -C 20 hydrocarboxy group, and
iv) M 3 is Zr;

the solid-oxide chemically-treated with an electron withdrawing anion comprises fluorided alumina, chlorided alumina, sulfated alumina, fluorided silica-alumina, or any combination thereof;
the organoaluminum compound comprises a trialkylaluminum, an alkylaluminum sesquihalide, an alkylaluminum halide, or any combination thereof;
the alpha olefin monomer and catalyst system are contacted at
i) an aluminum of the organoaluminum compound to metal of the metallocene (Al:metal) molar ratio ranging from 50:1 to 500:1;
ii) a first activator to metallocene weight ratio ranging from 100:1 to 1,000:1;
iii) an alpha olefin monomer to metallocene weight ratio ranging from 1,000:1 to 10,000,000:1;

the oligomerization conditions comprise a temperature ranging from 50° C. to 165° C.;
at least 80 weight % of the alpha olefin monomer is converted to the oligomer product; and
the oligomer product comprises at least 75 weight% higher oligomers.

10. A method for producing a polyalphaolefin, the method comprising:
a) contacting an alpha olefin monomer and a catalyst system, wherein the alpha olefin monomer comprises at least 80 weight percent of a C 8 to C 16 normal alpha olefin, and wherein the catalyst system comprises:
1) a metallocene,
2) a first activator comprising a solid oxide chemically-treated with an electron withdrawing anion, and
3) a second activator comprising an organoaluminum compound having the formula: Al(X 10 ) n (X 11 ) 3-n , wherein X 10 is independently a C 1 to C 20 hydrocarbyl, X 11 is independently a halide, a hydride, or a C 1 to C 20 hydrocarboxide, and n is a number from 1 to 3;
wherein the catalyst system is devoid of added aluminoxane;

b) forming an oligomer product comprising dimers, trimers, and higher oligomers in an oligomerization reactor under oligomerization conditions;
c) separating an effluent of the oligomerization reactor comprising the oligomer product to provide a heavy oligomer product, wherein at least a portion of the alpha olefin monomer, dimers, or trimers are removed from the effluent of the oligomerization reactor to form the heavy oligomer product; and
d) hydrogenating the heavy oligomer product to produce the polyalphaolefin, wherein the polyalphaolefin has a pour point less than 0° C.

11. The method for producing a polyalphaolefin of claim 10 , wherein:
1) the alpha olefin monomer comprises a C 8 to C 12 normal alpha olefin;
2) the metallocene has the formula (η 5 -cycloalkadienyl) 2 M 3 X 9 2 , wherein:
i) the two η 5 -cycloalkadienyl ligands are linked by a linking group having the structure >CR 1 R 2 , >SiR 3 R 4 , or —CR 5 R 6 CR 7 R 8 —, wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 are selected independently from hydrogen or a saturated or unsaturated C 1-20 hydrocarbyl group,
ii) each η 5 -cycloalkadienyl ligand independently is a substituted or an unsubstituted cyclopentadienyl ligand, a substituted or an unsubstituted indenyl ligand, or a substituted or an unsubstituted fluorenyl ligand,
wherein each non-linking substituent independently is a halide, a C 1 to C 20 hydrocarbyl group, or a C 1 to C 20 hydrocarboxy group,

iii) X 9 is a halide, a C 1 -C 20 hydrocarbyl group, or a C 1 -C 20 hydrocarboxy group, and
iv) M 3 is Zr;

3) the first activator comprises fluorided alumina, chlorided alumina, sulfated alumina, fluorided silica-alum

Assignees

• Chevron Phillips Chemical Co Lp

Inventors

• Small Brooke L
• Hope Kenneth D
• Yang Qing
• Masino Albert P
• Mcdaniel Max P
• Buck Richard M
• Beaulieu William B
• Baralt Eduardo J
• Netemeyer Eric J
• Kreischer Bruce

Classifications

• C10N2020/071

  Branched chain compounds · CPC title

• C10N2020/017

  Specific gravity or density · CPC title

• C10N2030/74

  Noack Volatility · CPC title

• C10N2030/10

  Inhibition of oxidation, e.g. anti-oxidants · CPC title

• C10N2030/02

  Pour-point; Viscosity index · CPC title