Claims
- 1. A process for producing a Fischer-Tropsch derived lubricating base oil blend which comprises blending a Fischer-Tropsch distillate fraction with a Fischer-Tropsch derived bottoms fraction in the proper proportion to produce a Fischer-Tropsch derived lubricating base oil characterized as having a kinematic viscosity of between about 3 and about 10 cSt at 100 degrees C. and a TGA Noack volatility of less than about 45 weight percent wherein said distillate fraction is characterized by a kinematic viscosity of about 2 cSt or greater but less than 3 cSt at 100 degrees C.
- 2. The process of claim 1 wherein the distillate fraction has a viscosity between about 2.1 and 2.8 cSt at 100 degrees C.
- 3. The process of claim 2 wherein the distillate fraction has a viscosity between about 2.2 and 2.7 cSt at 100 degrees C.
- 4. The process of claim 1 wherein the Fischer-Tropsch derived bottoms fraction has a kinematic viscosity between about 9 cSt and about 20 cSt at 100 degrees C.
- 5. The process of claim 4 wherein the bottoms fraction has a viscosity of between about 10 and about 16 cSt at 100 degrees C.
- 6. The process of claim 1 wherein the Fischer-Tropsch derived bottoms fraction is bright stock.
- 7. The process of claim 6 wherein the bright stock is produced by oligomerizing the olefins present in an olefin-containing Fischer-Tropsch derived condensate.
- 8. The process of claim 7 including the preliminary step of enriching the olefins in the Fischer-Tropsch condensate by the dehydration of the alcohols present in the condensate.
- 9. The process of claim 7 including the preliminary step of enriching the olefins in the Fischer-Tropsch condensate by the thermal cracking of the hydrocarbons present in the condensate.
- 10. The process of claim 1 wherein the lubricating base oil blend has a Noack volatility of less than 30 weight percent.
- 11. The process of claim 1 including the additional step of blending the Fischer-Tropsch lubricating base oil blend with at least one additive to produce a finished lubricant.
- 12. A process for producing a Fischer-Tropsch derived lubricating base oil blends which comprises the steps of:
a) separating a Fisher-Tropsch derived condensate recovered from a Fischer-Tropsch synthesis zone into at least a first olefin-containing distillate fraction and a second Fischer-Tropsch distillate fraction, said second light distillate fraction having a viscosity of about 2 cSt or greater but less than 3 cSt at 100 degrees C.; b) oligomerizing the olefins in the first olefin-containing distillate fraction to produce a Fischer-Tropsch derived bright stock; c) blending the second light Fischer-Tropsch distillate fraction with the Fischer-Tropsch derived bright stock in the proper proportion to produce a Fischer-Tropsch derived lubricating base oil characterized as having a viscosity of between about 3 and about 10 cSt at 100 degrees C. and a TGA Noack volatility of less than about 45 weight percent.
- 13. The Fischer-Tropsch derived lubricating base oil blend of claim 12 wherein the first olefin-containing distillate fraction as initially separated from the condensate also contains alcohols and at least some of the olefins present in said first olefin-containing distillate fraction are produced by the dehydration of said alcohols.
- 14. The Fischer-Tropsch derived lubricating base oil blend of claim 12 wherein at least some of the olefins present in the first olefin-containing distillate fraction are produced by cracking the hydrocarbons present in said first olefin-containing distillate fraction to produce an olefin enriched first distillate fraction.
- 15. The process of claim 14 wherein at least some of the hydrocarbons in the first olefin-containing distillate fraction are cracked in a thermal cracking operation to produce the olefin enriched first distillate fraction.
- 16. The process of claim 12 including the intermediate step of isomerizing the bright stock prior blending it with the second distillate fraction.
- 17. A Fischer-Tropsch derived lubricating base oil blend having a viscosity of between about 3 and about 10 cSt at 100 degrees C. and a TGA Noack volatility of less than about 45 weight percent said Fischer-Tropsch derived lubricating base oil blend comprising a Fischer-Tropsch distillate fraction and a Fischer-Tropsch derived bottoms fraction wherein:
(a) said distillate fraction is characterized by a viscosity of about 2 cSt or greater but less than 3 cSt at 100 degrees C. and (b) said Fischer-Tropsch derived bottoms fraction is characterized by a viscosity of not less than about 7 cSt at 100 degrees C.
- 18. The Fischer-Tropsch derived lubricating base oil blend of claim 17 wherein the distillate fraction has a viscosity between about 2.1 and 2.8 cSt at 100 degrees C.
- 19. The Fischer-Tropsch derived lubricating base oil blend of claim 18 wherein the distillate fraction has a viscosity between about 2.2 and 2.7 cSt at 100 degrees C.
- 20. The Fischer-Tropsch derived lubricating base oil of claim 17 having a boiling range distribution of at least 450 degrees F. between the 5 percent and 95 percent points by analytical method D-6352 or its equivalent.
- 21. The Fischer-Tropsch lubricating base oil of claim 17 wherein the TGA Noack volatility is 12 weight percent or greater.
- 22. The Fischer-Tropsch lubricating base oil of claim 21 wherein the TGA Noack volatility is greater than about 20 weight percent.
- 23. The Fischer-Tropsch lubricating base oil blend of claim 17 wherein the TGA volatility is less than about 30 weight percent.
- 24. The Fischer-Tropsch lubricating base oil of claim 17 wherein the VI is between about 130 and about 185.
- 25. The Fischer-Tropsch lubricating base oil of claim 17 wherein the total sulfur content is less than about 5 ppm.
- 26. The Fischer-Tropsch lubricating base oil of claim 17 wherein the Fischer-Tropsch derived bottoms fraction comprises bright stock.
- 27. The Fischer-Tropsch derived lubricating base oil of claim 26 wherein the cloud point of the blend is lower than the cloud point of either the distillate fraction or the bright stock.
- 28. A Fischer-Tropsch derived lubricating base oil blend characterized by a viscosity of between about 3 and about 10 cSt at 100 degrees C.; a TGA Noack volatility of less than 45 weight percent; an initial boiling point within the range of between about 550 degrees F. and about 625 degrees F.; an end boiling point between about 1000 degrees F. and about 1400 degrees F.; and wherein less than 30 weight percent of the blend boils within the region defined by the 50 percent boiling points, plus or minus 25 degrees F.
- 29. The Fischer-Tropsch derived lubricating base oil blend of claim 28 having a boiling range distribution of at least 450 degrees F. between the 5 percent and 95 percent points as measured by analytical method D-6352 or its equivalent.
- 30. The Fischer-Tropsch lubricating base oil blends of claim 28 wherein the TGA Noack volatility is 12 weight percent or greater.
- 31. The Fischer-Tropsch lubricating base oil blend of claim 30 wherein the TGA volatility is greater than about 20 weight percent.
- 32. The Fischer-Tropsch lubricating base oil blend of claim 28 wherein the TGA volatility is less than about 30 weight percent.
- 33. The Fischer-Tropsch lubricating base oil blend of claim 28 wherein the VI is between about 130 and about 185.
- 34. The Fischer-Tropsch lubricating base oil blend of claim 28 wherein the total sulfur content is less than about 5 ppm.
- 35. A finished lubricant comprising a Fischer-Tropsch derived lubricating base oil blend and at least one additive wherein the Fischer-Tropsch derived lubricating base oil blend is characterized by a viscosity of between about 3 and about 10 cSt at 100 degrees C. and comprises a Fischer-Tropsch distillate fraction and a Fischer-Tropsch derived bottoms fraction wherein:
(a) said distillate fraction is characterized by a viscosity of about 2 cSt or greater but less than 3 cSt at 100 degrees C. and (b) said Fischer-Tropsch derived bottoms fraction is characterized by a viscosity of not less than about 9 cSt at 100 degrees C.
- 36. The finished lubricant of claim 35 wherein the lubricating base oil blend has a Noack volatility of less than about 30 weight percent.
- 37. The finished lubricant of claim 36 which is suitable for use as an engine oil crankcase lubricant.
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is related to co-pending U.S. patent application Ser. No. 10/235,150 filed Sep. 4, 2002, titled “Blending of Low Viscosity Fischer-Tropsch Base Oils to Produce High Quality Lubricating Base Oils” and U.S. patent application Ser. No. 10/301,391 filed Nov. 20, 2002, titled “Blending of Low Viscosity Fischer-Tropsch Base Oils With Conventional Base Oils to Produce High Quality Lubricating Base Oils”.