Method for improving deposit control

Patent metadata

Field	Value
Publication number	US-9617494-B2
Application number	US-201514662402-A
Country	US
Kind code	B2
Filing date	Mar 19, 2015
Priority date	Apr 18, 2014
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

A method for improving deposit control, while maintaining or improving demulsibility performance, in an engine lubricated with a lubricating oil by using as the lubricating oil a formulated oil that has a particular phenate/carboxylate detergent mixture present in a particular amount in the formulated oil. A lubricating engine oil having a composition including a lubricating oil base stock as a major component; and a phenate/carboxylate detergent mixture as a minor component. The lubricating oils of this disclosure are useful in marine crankcase systems, in particular, marine system oil applications for two-stroke marine diesel engines.

First claim

What is claimed is:

1. A method for improving deposit control, while maintaining or improving demulsibility performance, in an engine lubricated with a lubricating oil by using as the lubricating oil a formulated oil, said formulated oil having a composition comprising a lubricating oil base stock as a major component; and a detergent mixture comprising a first detergent comprising an overbased phenate compound at from 1.0 to 1.5 wt. % of the lubricating oil, and at least one other detergent different from said first detergent wherein the at least one other detergent comprises a carbonated calcium monosalicylate (carboxylate) at from 2.0 to 3.0 wt. % of the lubricating oil, and the amount of the detergent mixture is at least 3.5 wt. % in the lubricating oil with the proviso that the lubricating oil does not include a dispersant, wherein the lubricating oil exhibits improved deposit control, while demulsibility performance is maintained or improved, as compared to deposit control and demulsibility performance achieved using a lubricating oil not containing the detergent mixture in the lubricating oil.

2. The method of claim 1 wherein the lubricating oil base stock comprises a Group I or Group fl base oil.

3. The method of claim 1 wherein the at least one other detergent further corn rises an alkylphenol, noncarbonated calcium alkylphenate and noncarbonated calcium monosalicylate (carboxylate) mixture at about 0.5 wt. % of the lubricating oil.

4. The method of claim 1 wherein the formulated oil further comprises an antiwear additive; wherein the antiwear additive comprises a zinc dialkyl dithiophosphate compound represented by the formula
Zn[SP(S)(OR 1 )(OR 2 )] 2

wherein R 1 and R 2 are independently primary or secondary C 1 to C 8 alkyl groups.

5. The method of claim 4 wherein the primary or secondary C 1 to C 8 alkyl groups of the zinc dialkyl dithiophosphate compound are derived from an alcohol selected from the group consisting of: 2-propanol, 1-butanol, 1-isobutanol, 2-butanol, 1-pentanol, 3-methyl-1-butanol, 2-pentanol, 3-pentanol, 3-methyl-2-butanol, 1-hexanol, 4-methyl-1-pentanol, 4-methyl-2-pentanol, and 2-ethyl-1-hexanol, and mixtures thereof.

6. The method of claim 4 wherein the zinc dialkyl dithiophosphate compound having the R 1 and R 2 primary or secondary alkyl groups, is present in an amount of from 0.1 weight percent to 1.2 weight percent, based on the total weight of the lubricating oil; or wherein the zinc dialkyl dithiophosphate compound having the R 1 and R 2 primary or secondary alkyl groups; in which the R 1 and R 2 primary or secondary alkyl groups are derived from 2-ethyl-1-hexanol, is present in an amount of from 0.1 weight percent to 0.8 weight percent, based on the total weight of the lubricating oil; or wherein the zinc dialkyl dithiophosphate compound having the R 1 and R 2 primary or secondary alkyl groups, in which the R 1 and R 2 primary or secondary alkyl groups are derived from 4-methyl-2-pentanol, is present in an amount of from 0.1 weight percent to 0.8 weight percent, based on the total weight of the lubricating oil; or wherein the zinc dialkyl dithiophosphate compound having the R 1 and R 2 primary or secondary alkyl groups, in which the and R 2 primary or secondary alkyl groups are derived from 2-propanol, 2-butanol, 1-iso-butanol, or n-pentanol, is present in an amount of from 0.3 weight percent to 0.8 weight percent, based on the total weight of the lubricating oil.

7. The method of claim 1 wherein the lubricating oil is a marine lubricating oil.

8. The method of claim 1 wherein the lubricating oil further comprises one or more of a viscosity index improver; antioxidant, pour point depressant, corrosion inhibitor, metal deactivator, seal compatibility additive, anti-foam agent, inhibitor, anti-rust additive, and friction modifier.

9. The method of claim 1 wherein, in deposit measurements of the lubricating oil as measured by Komatsu Hot Tube Test, deposit control is improved by at least 1 rating point as compared to deposit control of a lubricating oil not containing the detergent mixture.

10. The method of claim 1 wherein, in demulsibility measurements of the lubricating oil as measured by High Shear Demulsibility Test, the lubricating oil achieves at least 3.8 mL free water; less than 1 mL emulsion, and less than 1 weight percent water in oil.

11. A lubricating engine oil having a composition comprising a lubricating oil base stock as a major component; and a detergent mixture comprising a first detergent comprising an overbased phenate compound at from 1.0 to 1.5 wt. % of the lubricating oil, and at least one other detergent different from said first detergent wherein the at least one other detergent comprises a carbonated calcium monosalicylate (carboxylate) at from 2.0 to 3.0 wt. % of the lubricating oil, and the amount of the detergent mixture is at least 3.5 wt. % in the lubricating oil with the proviso that the lubricating oil does not include a dispersant, wherein the lubricating oil exhibits improved deposit control, while demulsibility performance is maintained or improved, as compared to deposit control and demulsibility performance achieved using a lubricating oil not containing the detergent mixture in the lubricating oil.

12. The lubricating engine oil of claim 11 wherein the lubricating oil base stock comprises a Group I or Group H base oil.

13. The lubricating engine oil of claim 11 wherein the at least one other detergent further comprises an alkylphenol, noncarbonated calcium alkylphenate and noncarbonated calcium monosalicylate (carboxylate) mixture at about 0.5 wt. % of the lubricating oil.

14. The lubricating engine oil of claim 11 wherein the formulated oil further comprises an antiwear additive; wherein the antiwear additive comprises a zinc dialkyl dithiophosphate compound represented by the formula
Zn[SP(S)(OR 1 )(OR 2 )] 2

wherein R 1 and R 2 are independently primary or secondary C1 to C8 alkyl groups.

15. The lubricating engine oil of claim 14 wherein the primary or secondary C 1 to C 8 alkyl groups of the zinc dialkyl dithiophosphate compound are derived from an alcohol selected from the group consisting of: 2-propanol, 1-butanol, 1-isobutanol, 2-butanol, 1-pentanol, 3-methyl-1-butanol, 2-pentanol, 3-pentanol, 3-methyl-2-butanol, 1-hexanol, 4-methyl-1-pentanol, 4-methyl-2-pentanol, and 2-ethyl-1-hexanol, and mixtures thereof.

16. The lubricating engine oil of claim 14 wherein the zinc dialkyl dithiophosphate compound having the R 1 and R 2 primary or secondary alkyl groups, is present in an amount of from 0.1 weight percent to 1.2 weight percent, based on the total weight of the lubricating oil; or wherein the zinc dialkyl dithiophosphate compound having the R 1 and R 2 primary or secondary alkyl groups, in which the R 1 and R 2 primary or secondary alkyl groups are derived from 2-ethyl-1-hexanol, is present in an amount of from 0.1 weight percent to 0.8 weight percent, based on the total weight of the lubricating engine oil; or wherein the zinc dialkyl dithiophosphate compound having the R 1 and R 2 primary or secondary alkyl groups, in which the and R 2 primary or secondary alkyl groups are derived from 4-methyl-2-pentanol, is present in an amount of from 0.1 weight percent to 0.8 weight percent, based on the total weight of the lubricating engine oil; or
wherein the zinc dialkyl dithiophosphate compound having the R 1 and R 2 primary or secondary alkyl groups, in which the R 1 and R 2 primary or secondary alkyl groups are derived from 2-propanol, 2-butanol, 1-iso-butanol,

Assignees

• Vander Neut Christopher J
• Crouthamel Kevin L
• Fogarty John T
• Exxonmobil Res & Eng Co

Inventors

• Vander Neut Christopher J
• Crouthamel Kevin L
• Fogarty John T

Classifications

• C10M2207/262

  derived from hydroxy substituted aromatic acids, e.g. salicylates · CPC title

• C10N2030/08

  Resistance to extreme temperature · CPC title

• C10M2219/044

  Sulfonic acids, Derivatives thereof, e.g. neutral salts · CPC title

• C10M129/54

  containing hydroxy groups · CPC title

• C10M141/08

  at least one of them being an organic sulfur-, selenium- or tellurium-containing compound · CPC title