Method for conversion of waste plastics to lube oil

• US 6,150,577 A
• Filed: 12/30/1998
• Issued: 11/21/2000
• Est. Priority Date: 12/30/1998
• Status: Expired due to Term

• Current Assignee: Chevron USA Incorporated (Chevron Corp.), University Of Kentucky Research Foundation (University of Kentucky)
• Original Assignee: Chevron USA Incorporated (Chevron Corp.)
• Inventors: Miller, Stephen J., Huffman, Gerald P., Shah, Naresh
• Primary Examiner(s): Griffin, Walter D.
• Assistant Examiner(s): NGUYEN, TAM M
• Application Number:
  US09/224,554
• Time in Patent Office: 692 Days
• Field of Search: 208/69, 208/97, 208/134, 585/240, 585/241, 585/734, 585/739
• US Class Current: 585/241
• CPC Class Codes: C10G 1/002 in combination with oil conversion- or refining processes
• CPC Class Codes: C10G 1/02 by distillation
• CPC Class Codes: C10G 1/10 from rubber or rubber waste
• CPC Class Codes: C10G 65/043 at least one step being a change in the structural skeleton

Abstract

The invention includes a process of making a lubricating oil composition including: a process for making a high VI lubricating oil composition including the steps of (1) contacting a waste plastics feed including mainly polyethylene in a pyrolysis zone at pyrolysis conditions, whereby at least a portion of the waste plastics feed is cracked, thereby forming a pyrolysis zone effluent including 1-olefins and n-paraffins; (2) passing the pyrolysis zone effluent, including a heavy fraction and a middle fraction, the pyrolysis effluent middle fraction including 1-olefins, to a separations zone; where the pyrolysis effluent heavy fraction portion is separated from the pyrolysis effluent middle fraction; (3) passing the pyrolysis effluent heavy fraction to a hydrogenation zone; and (4) passing at least a portion of the hydrogenation zone effluent to a catalytic isomerization dewaxing zone, where at least a portion of the hydrogenation zone effluent is contacted with a isomerization dewaxing catalyst at isomerization dewaxing conditions thereby forming a high VI lubricating oil composition.

Claims

1. A process for making a high VI lubricating oil composition comprising the steps of:

(a) passing a waste plastics feed comprising polyethylene to a pyrolysis zone, having a sub-atmospheric pressure, whereby at least a portion of said waste plastics feed is cracked, thereby forming a pyrolysis zone effluent comprising 1-olefins and n-paraffins;

(b) passing said pyrolysis zone effluent to a separations zone, thereby separating said pyrolysis zone effluent into at least one heavy fraction and one middle fraction, said middle fraction comprising 1-olefins;

(c) passing at least a portion of said pyrolysis effluent heavy fraction to a catalytic hydrotreating zone wherein at least a portion of said pyrolysis effluent heavy fraction is contacted with a hydrotreating catalyst at hydrotreating conditions, thereby producing a hydrotreated pyrolysis effluent heavy fraction;

(d) passing at least a portion of said hydrotreated pyrolysis effluent heavy fraction to a catalytic isomerization dewaxing zone, wherein at least a portion of said hydrotreated pyrolysis effluent heavy fraction is contacted with an isomerization dewaxing catalyst at isomerization dewaxing conditions, wherein at least a portion of said hydrotreated pyrolysis effluent heavy fraction is converted to a high VI lubricating oil composition; and

(e) wherein said high VI lubricating oil composition comprises a lube fraction having a kinematic viscosity at 100°

C. of at least about 8 cSt.

2. The process of claim 1, wherein a major portion of said high VI lubricating oil composition boils in the bright stock range.

3. The process of claim 1, wherein said pyrolysis zone is at sub-atmospheric pressure not greater than about 0.75 atmospheres.

4. The process of claim 1, wherein said pyrolysis zone is at sub-atmospheric pressure not greater than about 0.50 atmospheres.

5. The process of claim 1, wherein said lube fraction having a kinematic viscosity at 100°

C. of at least about 8 cSt comprises a substantial portion of said high VI lubricating oil composition.

6. The process of claim 1, wherein said lube fraction having a kinematic viscosity at 100°

C. of at least about 8 cSt comprises a major portion of said high VI lubricating oil composition.

7. The process of claim 1, wherein pyrolysis zone includes an inert gas selected from the group consisting of nitrogen, hydrogen, steam, methane or a recycled light fraction from said separations zone in step (b).

8. The process of claim 1, wherein said isomerization dewaxing catalyst comprises an intermediate pore size molecular sieve.

9. The process of claim 1, wherein said isomerization dewaxing catalyst comprises an intermediate pore size molecular sieve selected from the group consisting of ZSM-22, ZSM-23, SSZ-32, ZSM-35, SAPO-11, SM-3, and mixtures thereof.

10. The process of claim 1, wherein said isomerization dewaxing catalyst consists essentially of an intermediate pore size molecular sieve selected from the group consisting of SSZ-32, SAPO-11, SM-3, and mixtures thereof.

11. The process of claim 1, wherein said isomerization dewaxing catalyst consists essentially of SSZ-32.

12. The process of claim 1, wherein said waste plastics feed comprises at least about 95 wt. % polyethylene.

13. The process of claim 1, wherein from about 25 wt. % to about 75 wt. % of said pyrolysis zone effluent comprises 1-olefins.

14. The process of claim 1, wherein the yield of said high VI lubricating oil composition based on the weight of said hydrotreated pyrolysis effluent heavy fraction is at least about 50 wt. %.

15. The process of claim 1, wherein the yield of said high VI lubricating oil composition based on the weight of said hydrotreated pyrolysis effluent heavy fraction is at least about 60 wt. %.

16. The process of claim 1, wherein the yield of said high VI lubricating oil composition based on the weight of said hydrotreated pyrolysis effluent heavy fraction is at least about 70 wt. %.

17. The process of claim 1, wherein said pyrolysis zone is a temperature of from about 500°

C. to about 700°

C.

18. The process of claim 1, wherein said pyrolysis zone is a temperature of from about 600°

C. to about 700°

C.

19. The process of claim 1, wherein prior to passing said waste plastic feed to said pyrolysis zone, said waste plastic feed is ground and substantially liquefied.

20. The process of claim 1, wherein the S and N levels of said hydrotreated pyrolysis effluent heavy fraction portion are not greater than about 5 ppm S and 1 ppm N.

21. The process of claim 1, wherein said high VI lubricating oil composition has a pour point not greater than about 20°

F.

22. The process of claim 1, wherein said high VI lubricating oil composition has a cloud point of not more than about 10°

F. higher than its pour point.

23. The process of claim 1, wherein said high VI lubricating oil composition has a pour point not greater than about 15°

F.

24. The process of claim 1, wherein said high VI lubricating oil composition has a cloud point not greater than about 25°

F.

25. A process for making a high VI lubricating oil composition comprising the steps of:

(a) passing a waste plastics feed comprising polyethylene to a pyrolysis zone having a temperature of from about 600°

C. to about 700°

C. and pressure not greater than about 0.75 atm., whereby at least a portion of said waste plastics feed is cracked, thereby forming a pyrolysis zone effluent comprising 1-olefins and n-paraffins;

(b) passing said pyrolysis zone effluent, to a separations zone, thereby separating said pyrolysis zone effluent into at least one heavy fraction and one middle fraction, said middle fraction comprising 1-olefins;

(c) passing at least a portion of said pyrolysis effluent heavy fraction to a catalytic hydrotreating zone wherein at least a portion of said pyrolysis effluent heavy fraction is contacted with a hydrotreating catalyst at hydrotreating conditions, thereby producing a hydrotreated pyrolysis effluent heavy fraction;

(d) passing at least a portion of said hydrotreated pyrolysis effluent heavy fraction to a catalytic isomerization dewaxing zone, wherein at least a portion of said hydrotreated pyrolysis effluent heavy fraction is contacted with an isomerization dewaxing catalyst at isomerization dewaxing conditions, wherein at least a portion of said hydrotreated pyrolysis effluent heavy fraction is converted to a high VI lubricating oil composition;

(e) wherein said high VI lubricating oil composition comprises a lube fraction having a kinematic viscosity at 100°

C. of at least about 8 cSt; and

(f) wherein said high VI lubricating oil composition has a pour point not greater than about 15°

F.

26. The process of claim 25, wherein said high VI lubricating oil composition has a cloud point not greater than about 25°

F.

27. The process of claim 25, wherein said lube fraction having a kinematic viscosity at 100°

C. of at least about 8 cSt comprises at least 10 weight percent of said high VI lubricating oil composition.

28. The process of claim 25, wherein said lube fraction having a kinematic viscosity at 100°

C. of at least about 8 cSt comprises at least 50 weight percent of said high VI lubricating oil composition.