LUBRICATING OIL COMPOSITION

Abstract

Disclosed is a lubricating oil composition comprising: a major amount of an oil of lubricating viscosity, and an salicylate compound derived from isomerized normal alpha olefin (NAO) having from about 10 to about 40 carbon atoms, wherein the TBN of the salicylate compound is at least 600 mg KOH/g on an actives basis, and wherein the lubricating oil composition contains from about 0.12 to about 0.17 wt. % of calcium and is substantially free of magnesium. Also provided is a method of lubricating an engine with said lubricating oil composition.

Claims

1. A lubricating oil composition comprising: (a) a major amount of an oil of lubricating viscosity, and (b) an salicylate compound derived from isomerized normal alpha olefin (NAO) where the isomerized level (I) of the alpha olefin is between from about 0.1 to about 0.4 and having from about 10 to about 40 carbon atoms, wherein the TBN of the salicylate compound is at least 600 mg KOH/g on an actives basis; wherein the lubricating oil composition contains from about 0.12 to about 0.17 wt. % of calcium and is substantially free of magnesium and the total SOAP content from all the detergents is less than 18 mM; wherein the isomerization level (I) represents the relative amount of methyl groups (CH3) (chemical shift 0.3-1.01 ppm) attached to the methylene backbone groups (CH2-) (chemical shift 1.01-1.38 ppm) and is defined by Equation (1),
I=m/(m+n)Equation (I) where m is NMR integral for methyl groups with chemical shifts between 0.30.03 to 1.010.03 ppm, and n is NMR integral for methylene groups with chemical shifts between 1.010.03 to 1.380.10 ppm.

2. The lubricating oil composition of claim 1, further comprising a zinc dithiophosphate compound.

3. The lubricating oil composition of claim 1, further comprising a molybdenum dithiocarbamate.

4. The lubricating oil composition of claim 1, wherein magnesium is present at less than 50 ppm.

5. The lubricating oil composition of claim 1, wherein the lubricating oil composition reduces corrosion in an engine.

6. The lubricating oil composition of claim 1, wherein the engine is an internal combustion engine equipped with an EGR system.

7. The lubricating oil composition of claim 5, wherein the engine is a hybrid engine, or a turbo GDI engine.

8. A method of lubricating an engine comprising lubricating said engine with a lubricating oil composition comprising: (a) a major amount of an oil of lubricating viscosity, and (b) an salicylate compound derived from isomerized normal alpha olefin (NAO) where the isomerized level (I) of the alpha olefin is between from about 0.1 to about 0.4 and having from about 10 to about 40 carbon atoms, wherein the TBN of the salicylate compound is at least 600 mg KOH/gm on an actives basis, wherein the lubricating oil composition contains from about 0.12 to about 0.17 wt. % of calcium and is substantially free of magnesium and the total SOAP content from all the detergents is less than 18 mM; wherein the isomerization level (I) represents the relative amount of methyl groups (CH3) (chemical shift 0.3-1.01 ppm) attached to the methylene backbone groups (CH2-) (chemical shift 1.01-1.38 ppm) and is defined by Equation (1),
I=m/(m+n)Equation (I) where m is NMR integral for methyl groups with chemical shifts between 0.30.03 to 1.010.03 ppm, and n is NMR integral for methylene groups with chemical shifts between 1.010.03 to 1.380.10 ppm.

9. The method of claim 8, wherein the engine is a hybrid engine, or a turbo GDI engine.

10. The method of claim 8, wherein the engine is an internal combustion engine equipped with an EGR system.

11. The method of claim 8, wherein the lubricating oil composition reduces corrosion in the engine.

12. The method of claim 8, wherein the lubricating oil composition further comprises a zinc dithiophosphate compound.

13. The method of claim 8, wherein the lubricating oil composition further comprises a molybdenum dithiocarbamate.

14. The method of claim 8, wherein magnesium is present at less than 50 ppm the lubricating oil composition.

Description

EXAMPLES

[0093] The following examples are intended for illustrative purposes only and do not limit in any way the scope of the present disclosure.

Isomerization Level (I) and NMR Method

[0094] The isomerization level (I) of the olefin was determined by hydrogen-1 (1H) NMR. The NMR spectra were obtained on a Bruker Ultrashield Plus 400 in chloroform-d1 at 400 MHz using TopSpin 3.2 spectral processing software.

[0095] The isomerization level (I) represents the relative amount of methyl groups (CH3) (chemical shift 0.3-1.01 ppm) attached to the methylene backbone groups (CH2-) (chemical shift 1.01-1.38 ppm) and is defined by Equation (1) as shown below,

I=m/(m+n)Equation (I)

where m is NMR integral for methyl groups with chemical shifts between 0.30.03 to 1.010.03 ppm, and n is NMR integral for methylene groups with chemical shifts between 1.010.03 to 1.380.10 ppm.

[0096] The isomerized level (I) of the alpha olefin is between from about 0.1 to about 0.4, preferably from about 0.1 to about 0.3, more preferably from about 0.12 to about 0.3.

[0097] In one embodiment, the isomerization level of the NAO is about 0.16, and having from about 20 to about 24 carbon atoms.

[0098] In another embodiment, the isomerization level of the NAO is about 0.26, and having from about 20 to about 24 carbon atoms.

Baseline Formulation 1

[0099] A 0W-16 lubricating oil composition was prepared that contained a major amount of a base oil of lubricating viscosity and the following additives: [0100] (1) an ethylene carbonate post-treated bis-succinimide; [0101] (2) a borated bis-succinimide [0102] (3) a mixture of primary and secondary zinc dialkyldithiophosphate in an amount of 0.077 wt. % phosphorus wherein the molar ratio of primary to secondary is 9:1; [0103] (4) a diphenylamine antioxidant; [0104] (5) a PMA comb polymer [0105] (6) a MoDTC compound in 0.085 wt. % of molybdenum; [0106] (7) a foam inhibitor; and [0107] (8) the remainder Group III base oil.

Detergent 1

[0108] An alkylated phenol and a Ca salicylate was prepared in substantially the same manner as in U.S. Pat. No. 8,993,499 using a C.sub.20-24 isomerized normal alpha olefin. The isomerization level of the alpha olefin is about 0.16. The resulting salicylate composition has a TBN of about 630 and Ca content of about 22.4 wt. % on an oil-free basis.

Detergent 2

[0109] An overbased calcium sulfonate with a TBN of 690, and Ca content of about 26 wt. % on an actives basis, with an alkyl group derived from C.sub.20-24 NAO.

Detergent 3

[0110] An salicylate was prepared with an alkyl group derived from C.sub.14-18 NAO and a TBN about 300 and Ca content about 10.6 wt % on an oil-free basis.

Detergent 4

[0111] An alkylated phenol and alkylated Ca salicylate were prepared in substantially the same manner as in U.S. Pat. No. 8,993,499 using a C.sub.20-24 isomerized normal alpha olefin available from CP Chem. The isomerization level of the alpha olefin is about 0.16. The resulting alkylated salicylate composition has a TBN of about 225 mgKOH/gm and Ca content of 8 wt. % on an oil-free basis.

Detergent 5

[0112] An alkylated phenol and alkylated Ca salicylate were prepared in substantially the same manner as in U.S. Pat. No. 8,993,499 using a C.sub.20-24 isomerized normal alpha olefin available from CP Chem. The isomerization level of the alpha olefin is about 0.16. The resulting alkylated salicylate composition has a TBN of about 120 mgKOH/gm and Ca content of 4.2 wt. % on an oil-free basis.

Detergent 6

[0113] An salicylate was prepared with an alkyl group derived from C.sub.14-18 NAO and a TBN about 520 and Ca content about 18.7 wt, % on an oil-free basis.

Example 1

[0114] To baseline formulation 1 was added 0.14 wt. % in terms of Ca content of a detergent 1 (35 mM). Total SOAP from the detergent mixture is given below in Table 2.

Example 2

[0115] To baseline formulation 1 was added 0.14 wt. % in terms of Ca content of a mixture of mixture of detergent 1 (15.0 mM), detergent 4 (10.0 mM), and detergent 5 (10.0 mM) in approximately a 1.5:1:1 mixture based on mM of detergent. Total SOAP from the detergent mixture is given below in Table 2.

Example 3

[0116] To baseline formulation 1 was added 0.14 wt. % in terms of Ca content of a mixture of detergent 1 (23.0 mM), detergent 4 (6.0 mM), and detergent 5 (6.0 mM) in approximately a 3.83:1:1 mixture based on mM of detergent. Total SOAP from the detergent mixture is given below in Table 2.

Example 4

[0117] To baseline formulation 1 was added 0.12 wt. % in terms of Ca content of a mixture of detergent 1 (19.8 mM), detergent 4 (5.10 mM), and detergent 5 (5.10 mM) in approximately a 3.88:1:1 mixture based on mM of detergent. Total SOAP from the detergent mixture is given below in Table 3

Example 5

[0118] To baseline formulation 1 was added 0.12 wt. % in terms of Ca content of a mixture of detergent 1 (12.9 mM), detergent 4 (8.55 mM), and detergent 5 (8.55 mM) in approximately a 1.5:1:1 mixture based on mM of detergent. Total SOAP from the detergent mixture is given below in Table 3.

Example 6

[0119] To baseline formulation 1 was added 0.12 wt. % in terms of Ca content of a mixture of detergent 1 (4.2 mM), detergent 4 (12.9 mM), and detergent 5 (12.9 mM) in approximately a 0.33:1:1 mixture based on mM of detergent. Total SOAP from the detergent mixture is given below in Table 3

Example 7

[0120] To baseline formulation 1 was added 0.16 wt. % in terms of Ca content of detergent 1 (40 mM). Total SOAP from the detergent mixture is given below in Table 4.

Comparative Example A

[0121] To baseline formulation 1 was added 0.14 wt. % in terms of Ca content of detergent 2 (35 mM). Total SOAP from the detergent mixture is given below in Table 2.

Comparative Example B

[0122] To baseline formulation 1 was added 0.14 wt. % in terms of Ca content of detergent 3 (35 mM). Total SOAP from the detergent mixture is given below in Table 2.

Comparative Example C

[0123] To baseline formulation 1 was added 0.14 wt. % in terms of Ca content of a mixture of detergent 1 (5 mM), detergent 4 (15 mM), and detergent 5 (15 mM) in a 0.33:1:1 mixture based on mM of detergent. Total SOAP from the detergent mixture is given below in Table 2.

Comparative Example D

[0124] To baseline formulation 1 was added 0.14 wt. % in terms of Ca content of detergent 6 (35 mM). Total SOAP from the detergent mixture is given below in Table 2.

Ball Rust Test (BRT)ASTM D6557

[0125] The Ball Rust test referred to herein is conducted using the method of ASTM-D-6557. The Ball Rust Test (BRT) is a procedure for evaluating the anti-corrosion ability of fluid lubricants. In accordance with ASTM D6557, a ball bearing is immersed in an oil. Air saturated with acidic contaminants is bubbled through the oil for 18 hours at 49 C. After the 18-hour reaction period, the ball is removed from the test oil and the amount of corrosion on the ball is quantified using a light reflectance technique. The amount of reflected light is reported as an average gray value (AGV). The AGV for a fresh un-corroded ball is approximately 140. A totally corroded ball has an AGV result of less than 20. A lubricating oil composition which gives an AGV of at least 100 passes the BRT. A lubricating oil composition which gives an AGV of less than 100 fails the BRT.

TABLE-US-00002 TABLE 2 BRT Test Results Comp Comp Comp Comp Ex 1 Ex 2 Ex 3 Ex A Ex B Ex C Ex D Ca (wt. %) 0.14 0.14 0.14 0.14 0.14 0.14 0.14 Total SOAP from 3.96 13.4 9.62 1.96 12.25 18.12 4.9 detergents (mM) BRT 126 113 112 91 81 86 81

TABLE-US-00003 TABLE 3 BRT Test Results Ex 4 Ex 5 Ex 6 Ca (wt. %) 0.12 0.12 0.12 Total SOAP from 8.2 11.46 15.57 detergents (mM) BRT 117 132 113

TABLE-US-00004 TABLE 4 BRT Test Results Ex 7 Ca (wt. %) 0.16 Total SOAP from 4.52 detergents (mM) BRT 122