Production of Shear-Stable High Viscosity PAO

• US 20090247442A1
• Filed: 02/19/2009
• Published: 10/01/2009
• Est. Priority Date: 03/31/2008
• Status: Active Grant

• Current Assignee: ExxonMobil Chemical Patents Inc. (Exxon Mobil Corporation)
• Original Assignee: ExxonMobil Chemical Patents Inc. (Exxon Mobil Corporation)
• Inventors: Jiang, Peijun, Wu, Margaret M., Yang, Norman, Hagemeister, Mark Paul
• Granted Patent: US 9,365,663 B2
• Time in Patent Office: Days
• US Class Current: 508/591
• CPC Class Codes: C08F 10/08 Butenes
• CPC Class Codes: C08F 10/14 Monomers containing five or more carbon atoms
• CPC Class Codes: C08F 2/00 Processes of polymerisation
• CPC Class Codes: C08F 210/08 Butenes
• CPC Class Codes: C08F 210/14 Monomers containing five or more carbon atoms
• CPC Class Codes: C08F 2500/03 Narrow molecular weight distribution, i.e. Mw/Mn < 3
• CPC Class Codes: C08F 2500/17 Viscosity

Abstract

The invention is directed to a process for the preparation of high viscosity lubricant base stocks by contacting alphaolefin feedstocks with single-site metallocene catalysts in a mixed flow or continuous stirred tank reactors.

Claims

1. A process for preparing a high viscosity PAO base stock, comprising contacting a catalyst system comprising a single-site metallocene and a non-coordinating anion with a feedstock comprising olefins, said olefins selected from at least one linear alpha-olefin having a carbon number of 4 to 18 (C4 to C18), in a mixed flow or continuously stirred tank reactors (CSTR) operation, and obtaining a product suitable for use as a lubricant and characterized by a KV₁₀₀ of about 3 to about 10,000 cSt, and a MWD of less than 2.5.

2. The process of claim 1, wherein said olefin feed, prior to said contacting, is characterized by a water content of less than 10 ppm.

3. The process according to claim 1, including a step of hydrogenating a crude product from said CSTR reactor and then obtaining a product suitable for use as a lubricant.

4. The process according to claim 1, including a step of filtering a crude product from said CSTR to obtain a product characterized as having less than 1000 ppm of particles having a mean diameter of >

4 microns and less than 1 ppm each of the metals Al, Zr, Si, and B.

5. The process according to claim 1, wherein said product suitable for use as a lubricant blend which is characterized by a KV₁₀₀ of about 3 to about 300 cSt, a MWD of 1.5-2.0, and a Viscosity Index of 195-220.

6. The process according to claim 1, wherein said product suitable for use as a lubricant is characterized by a KV₁₀₀ of about 20 to about 250 cSt, and a MWD of 1.5-2.0.

7. The process according to claim 1, wherein said product suitable for use as a lubricant is characterized by a KV₁₀₀ of about 90 to about 160 cSt, and a MWD of 1.5-2.0.

8. The process according to claim 1, wherein said product suitable for use as a lubricant is characterized by a KV₁₀₀ of about 250 to about 900 cSt, and a MWD of 1.5-2.0.

9. The process according to claim 1, wherein said product suitable for use as a lubricant is characterized by a KV₁₀₀ of about 300 to about 650 cSt, and a MWD of 1.5-2.0.

10. The process according to claim 1, wherein said olefin feedstock is a mixed feedstock which consists essentially of C10 and C12 alpha-olefins.

11. The process according to claim 1, wherein said olefin feedstock is a mixed feedstock which consists essentially of C6 and C12 alpha-olefins.

12. The process according to claim 1, wherein said olefin feedstock is a mixed feedstock which consists essentially of C12 and C14 alpha-olefins.

13. The process according to claim 1, wherein said olefin feedstock is a mixed feedstock which consists essentially of C6, C10, and C14 alpha-olefins.

14. The process according to claim 1, wherein said olefin feedstock is a mixed feedstock which consists of C6, C10, C12, and C14 alpha-olefins.

15. The process according to claim 1, including:

(a) a step of drying said olefin feedstock over molecular sieves so that the water content of said feed, prior to said contacting, is less than 10 ppm;

(b) contacting the olefin feedstock from step (a) with a catalyst system comprising a single site metallocene catalyst, an NCA activator, and a trialkyl aluminum co-activator, in a CSTR to obtain a crude product;

(c) separating said crude product from step (b) from said catalyst system;

(d) distilling said crude product to obtain a crude lubricant range PAO;

(e) filtering said crude lubricant range PAO to obtain a product characterized as having less than 1000 ppm of particles having a mean diameter of >

4 microns and less than 1 ppm each of the metals Al, Zr, Si, and B.

16. The process according to claim 1, wherein said product suitable for use as a lubricant is characterized by a MWD that is at least 10 percent less than given by the algorithm MWD=0.2223+[1.0232*log(Kv at 100°

C. in cSt)], more preferably less than given by the algorithm;

MWD=0.41667+[0.725*log(Kv at 100°

C. in cSt)], still more preferably less than the given by the algorithm MWD=0.66017+[0.44922*log(Kv at 100°

C. in cSt)].

17. A lubricant made by the process of claim 1, wherein the lubricant in a gear oil, bearing oil, circulating oil, compressor oil, hydraulic oil, turbine oil, or machinery grease.

18. The lubricant of claim 17, further comprising using the lubricant in a wet gearbox, clutch system, blower bearing, wind turbine gear box, coal pulverizer drive, cooling tower gear box, kiln drive, paper machine drive, or rotary screw compressor.