Alcohol-resistant low-viscosity lubricating oil composition and application thereof

Abstract

The invention provides an alcohol-resistant low-viscosity lubricating oil composition and application thereof. The lubricating oil composition comprises the following components in percentage by weight: 0.6 to 1.0 percent of metal detergent, 6.0 to 10.0 percent of ashless dispersant, 0.5 to 2.0 percent of antioxidant and antiwear agent, 1.0 to 2.0 percent of metal deactivator, 0.2 to 1.0 percent of extreme pressure antiwear agent, 3.0 to 5.0 percent of viscosity index improver, 0.1 to 0.2 percent of pour point depressant, 0.001 to 0.010 percent of anti-foaming agent, 30.0 to 50.0 percent of CTL base oil and the balance of API III base oil. The lubricating oil composition has excellent anti-wear durability and low-temperature cold starting performance.

Description

Technical Field

[0001] The invention belongs to the technical field of lubricating oils, and in particular relates to a lubricating oil composition whose performance meets the lubrication requirements of an M100 methanol passenger car engine. Background Art

[0002] At present, the viscosity level of M100 passenger car methanol oil is 5W-30. With the expansion of the promotion of methanol oil, the use of oil in cold areas in winter (-36℃) has caused poor cold start performance (no start within 5 seconds) and large start-up wear (the oil has poor fluidity and cannot reach the surface of the machine parts in time to play a lubricating effect). At the same time, in order to meet the demand for further extending the oil change mileage, higher requirements are placed on the anti-wear performance of oil products. Summary of the invention

[0003] In order to solve the above problems, the object of the present invention is to provide an alcohol-resistant low-viscosity lubricating oil composition and its application, wherein the lubricating oil composition has excellent anti-wear durability and low-temperature cold starting performance.

[0004] In order to achieve the above-mentioned purpose, the present invention has systematically studied various types of additives and different types of base oils in the lubricating oil composition, and has comprehensively and systematically studied the interactions and relationships between the various components. How to solve the anti-wear durability of the oil is one of the key goals to be overcome. By effectively combining base oils, extreme pressure anti-wear agents, antioxidants and metal deactivators, etc., the problems of reduced anti-wear performance of lubricating oil in the presence of methanol, formic acid and water and poor low-temperature cold starting performance of methanol engines have been successfully solved.

[0005] The invention provides an alcohol-resistant low-viscosity lubricating oil composition, which comprises, based on the total mass of the lubricating oil composition being 100%, 0.6-1.0% of a metal detergent (component A), 6.0-10.0% of an ashless dispersant (component B), 0.5-2.0% of an antioxidant and anti-wear agent (component C), 1.0-2.0% of a metal deactivator (component D), 0.2-1.0% of an extreme pressure and anti-wear agent (component E), 3.0-5.0% of a viscosity index agent (component F, also known as a viscosity index improver), 0.1-0.2% of a pour point depressant (component G), 0.001-0.010% of an anti-foaming agent (component H), 30.0-50.0% of CTL base oil (component I), the balance is API III base oil (component J); wherein the antioxidant and anti-wear agent includes alkaline zinc dithiophosphate, amine ashless antioxidant, and phenolic ashless antioxidant; the metal deactivator includes thiadiazole type metal deactivator and methylbenzotriazole type metal deactivator; the extreme pressure anti-wear agent includes thioether type extreme pressure anti-wear agent; in the antioxidant and anti-wear agent, the sulfur-phosphorus ratio of the alkaline zinc dithiophosphate is 1.8-1.9, and the zinc-phosphorus ratio is 1.1-1.2; in the extreme pressure anti-wear agent, the sulfur content of the thioether type extreme pressure anti-wear agent is 14.0-15.0%.

[0006] According to a specific embodiment of the present invention, preferably, the basic zinc dithiophosphate is basic zinc dioctyl alkyl dithiophosphate.

[0007] The present invention has conducted a lot of research work on different types of antioxidants and anti-wear agents. The antioxidant and anti-wear agent is a mixture of amine ashless antioxidants, phenol ashless antioxidants, and alkaline zinc dithiophosphate. Zinc dithiophosphate has excellent antioxidant, anti-wear, and anti-corrosion properties. It is generally believed that it plays an antioxidant role by capturing free radicals and decomposing hydroperoxides. Due to the characteristics of methanol fuel, the increase in water in the combustion product greatly affects the antioxidant and anti-wear properties of neutral ZDDP. According to laboratory research, alkaline zinc dithiophosphate, such as basic dioctyl alkyl dithiophosphate, exhibits good system stability and wear resistance in the presence of water, alcohol, and acid, and has a good synergistic effect with amine ashless antioxidants and phenol ashless antioxidants, and is particularly suitable for methanol fuel engine oil. Ashless antioxidants can provide hydrogen atoms for peroxide free radicals, destroy or prevent chain growth, and generate low-energy stable free radicals. Ashless antioxidants also have synergistic effects. When phenolic antioxidants and amine antioxidants are used together, they have obvious synergistic effects because phenol helps the regeneration of aromatic amines. The amount of antioxidant and anti-wear agent added in the present invention is limited to 0.5-2.0%, and the preferred suitable range is 0.5-1.8%.

[0008] During the use of oil products, due to the presence of oxygen, heat and light, the oil products will be oxidized and deteriorated. If the lubricating oil contains metals, such as copper, iron, etc., these metals, especially metal ions, will accelerate the oxidation rate of the oil products, generate acid, sludge and precipitation, and cause corrosion and wear of metal parts. In order to avoid the catalytic acceleration of the auto-oxidation of lubricating oil by metal ions, the present invention has carried out a large number of screening and compounding work on different types of metal deactivators. The metal deactivator is a mixture of thiadiazole-type metal deactivators and methylbenzotriazole-type metal deactivators. Benzotriazole is an inhibitor of non-ferrous metals copper and silver. It can form chelates with copper and is an effective metal deactivator, but it has poor oil solubility. In order to improve its oil solubility, a derivative of benzotriazole has been developed. It is used in combination with a phenolic antioxidant (2,6-di-tert-butyl-p-cresol) to have an outstanding synergistic effect. Thiadiazole metal deactivators are copper corrosion inhibitors that have the function of trapping active sulfur, thereby playing a metal deactivation role. They contain disulfide bonds and can form a sulfide film on the metal surface, inhibiting the metal's oxidation catalytic effect on oil products, greatly increasing the oxidation life and improving hydrolysis stability. The present invention limits the amount of metal deactivators to about 1.0-2.0% of the total weight of the lubricating oil composition.

[0009] In order to make the composition have excellent anti-wear performance, it is very important to choose and compound different types of anti-wear agents and the proportion of addition. For example, sulfide olefin anti-wear agents have high anti-sintering load and good heat resistance, but poor anti-wear performance; chlorinated paraffin has good anti-wear and extreme pressure properties and strong activity, but poor stability, easy to cause corrosion, and toxicity; the better the performance of phosphate amine salt anti-wear agents, the worse their thermal stability; nanoparticles have poor solubility and poor stability. The extreme pressure anti-wear agent in the present invention is a thioether type extreme pressure anti-wear agent (such as dibenzyl disulfide, etc.), and its sulfur content is 14.0-15.0%. Sulfide-type organic carboxylic acid esters can also be used as the sulfide-type extreme pressure anti-wear agent of the present application. Since the ester oil molecules have a highly active polar group "ester group", it has a good adsorption effect on the electron-rich metal surface, which is conducive to the spreading and maintenance of the lubricating oil film, has outstanding anti-wear performance, good heat resistance, good thermal stability, and low corrosion, and can effectively solve the problem of traditional anti-wear agent failure caused by methanol, formic acid, and water. The present invention limits the addition amount of the extreme pressure anti-wear agent to 0.2-1.0%, and its preferred suitable range is 0.2-0.8%.

[0010] According to a specific embodiment of the present invention, preferably, based on the mass of the antioxidant and anti-wear agent being 100%, the antioxidant and anti-wear agent comprises 40-60% alkaline zinc dithiophosphate, 20-30% amine ashless antioxidant, and 10-20% phenolic ashless antioxidant; among the metal deactivators, the mass ratio of the thiadiazole type metal deactivator to the methylbenzotriazole type metal deactivator is 1:2-2:1.

[0011] According to a specific embodiment of the present invention, preferably, the composition of the lubricating oil composition includes: 0.7-1.0% metal detergent, 6.0-8.0% ashless dispersant, 0.5-1.8% antioxidant and antiwear agent, 1.0-2.0% metal deactivator, 0.2-0.8% extreme pressure antiwear agent, 3.0-5.0% viscosity index agent, 0.1-0.2% pour point depressant, 0.001-0.010% antifoaming agent, 30.0-40.0% CTL base oil, and the balance is API III base oil (preferably 30-60%).

[0012] According to a specific embodiment of the present invention, preferably, the metal detergent includes calcium salt and magnesium salt.

[0013] According to a specific embodiment of the present invention, preferably, the calcium salt includes calcium salicylate and / or calcium sulfonate, and the magnesium salt includes magnesium salicylate and / or magnesium sulfonate. Sulfonate is used in engine oil, which can neutralize the acidic oxides formed during the use of the engine, and inhibit the oxidation and deterioration of lubricating oil or reduce the generation of high-temperature deposits on the surface of the piston ring area under high temperature conditions, so that the inside of the engine remains clean, and at the same time, the non-oil-soluble colloid or oxide element generated by the oxidation of lubricating oil and incomplete combustion of fuel can be solubilized in the oil, thereby inhibiting the tendency of forming deposits such as paint film, carbon deposition, and sludge. Alkyl salicylate is to introduce carboxyl groups on alkylphenols, and transfer the metal from the hydroxyl position to the carboxyl position. This conversion makes its molecular polarity extremely strong, and the high-temperature detergency is greatly improved. It has good high-temperature detergency, certain low-temperature dispersion, anti-oxidation and anti-corrosion, extreme pressure and anti-wear, and good synergy with other agents. The compounding of different types of detergents can bring into play the synergistic effect of additives. In addition to ensuring that the oil has a certain alkalinity to neutralize acidic substances, it can also have good detergency, rust resistance and low sulfate ash. In the present invention, the metal detergent accounts for about 0.6-1.0% of the total weight of the composition, and its preferred suitable range is 0.7-1.0%. If the amount is too small, the detergency of the oil will decrease, the alkalinity will be low, and the service life of the lubricant will be shortened. If the amount is too large, the ash content of the lubricant will increase, the frequency of low-speed pre-ignition will increase, and the role of other functional additives will be affected, and there will be no other beneficial effects.

[0014] According to a specific embodiment of the present invention, preferably, the ashless dispersant includes polyisobutylene succinimide, more preferably a high nitrogen high base number polymer polyisobutylene succinimide, whose nitrogen content is 1.8-2.2% and the base number is 46-55 mgKOH / g. Ashless dispersant is a surfactant, which is mainly used to disperse pollutants generated in the engine to ensure that the oil can flow freely. The dispersibility of ashless dispersant can help keep the engine clean, and in some cases, it helps to maintain the cleanliness of the piston. Different types of dispersants have different dispersing effects on sludge and sediments. High base number polymer dispersants generally have a better dispersing effect on sediments generated at high temperatures, while general molecular weight dispersants have a better dispersing effect on sludge generated at low temperatures. The ashless dispersant of the present invention is selected from high nitrogen content and base number polymer polyisobutylene succinimide, which, in addition to having a better dispersing effect, can also assist in reducing the performance decay of ZDDP, cooperate with the anti-wear effect of extreme pressure anti-wear agents, and increase the base number inventory of engine oil. The ashless dispersant accounts for about 6.0-10.0% of the total weight of the composition, and the preferred suitable range is 6.0-8.0%. If the amount is too small, the dispersibility of the oil will be reduced, the surface deposits of the engine parts will increase, and the sludge in the oil pan will be thicker. If the amount is too large, the additive will be wasted and the effect of other functional additives in the lubricating oil will be affected, and there will be no other beneficial effects.

[0015] According to a specific embodiment of the present invention, preferably, the viscosity modifier includes ethylene propylene copolymer, such as RHY615, 9230F, etc. The performance of the lubricating oil is closely related to the type and shear stability of the viscosity modifier. The viscosity modifier of the present invention preferably uses an ethylene propylene copolymer with a shear index of 20. The viscosity modifier of the present invention accounts for about 3.0-5.0% of the total weight of the composition. If the amount is too small, the viscosity will be low, the thickness and stability of the oil film will decrease, and the anti-wear performance of the oil will be reduced in actual use. If the amount is too large, the additive will be wasted, the viscosity of the oil will be too large, and the low temperature performance and cleaning performance will be reduced, and there will be no other beneficial effects.

[0016] According to a specific embodiment of the present invention, preferably, the pour point depressant includes polymethacrylate. The addition of the pour point depressant will reduce the pour point of the lubricating oil and improve the use effect of the oil product in a low temperature environment. The present invention does not specifically limit the amount of the pour point depressant, which is usually 0.1-0.2% of the total mass of the lubricating oil composition. If the value is less than 0.1%, the amount is too small, which will cause the pour point of the lubricating oil to fail to meet the standard requirements and affect the fluidity in a low temperature environment.

[0017] According to a specific embodiment of the present invention, preferably, the antifoaming agent includes dimethyl silicone oil. The antifoaming agent can reduce the phenomenon of foaming of the lubricating oil due to mechanical stirring during actual use, and avoid the problem of oil film rupture and wear of engine parts caused by the generation of a large amount of foam during use. The present invention does not specifically limit the amount of antifoaming agent, which is usually 0.001-0.010% of the total mass of the lubricating oil composition. If the value is lower than 0.001%, the amount is too little, which will cause a decrease in antifoaming properties. If the value is higher than 0.010%, the amount is too much, which will result in a waste of additives and no other beneficial effects.

[0018] According to a specific embodiment of the present invention, preferably, the CTL base oil has a kinematic viscosity of 3.8-4.2 mm at 100°C. 2 / s coal-based synthetic oil, more preferably 4mm 2 / s.

[0019] According to a specific embodiment of the present invention, preferably, the API III base oil has a kinematic viscosity of 3.8-4.3 mm at 100°C. 2 / s API III hydrocracked base oil, preferably 4mm 2 / s.

[0020] According to a specific embodiment of the present invention, preferably, the lubricating oil composition has a sulfur content of 0.20-0.30wt%, a phosphorus content of 0.06-0.07wt%, a base number of 9.0-11.0mgKOH / g, a sulfated ash content of 0.4-0.6wt%, and a four-ball wear spot diameter of the lubricating oil composition after a 120-hour endurance test of an M100 methanol engine in accordance with NB / SH / T 0189 is less than 0.8mm, and the methanol engine is started within 3.5 seconds at -36°C.

[0021] According to a specific embodiment of the present invention, preferably, the base oils mentioned above are two high viscosity index base oil compositions whose performance meets the requirements of API Group III base oil standards.

[0022] The present invention also provides application of the lubricating oil composition in an M100 methanol passenger car engine.

[0023] The present invention, based on the action mechanism of additives, systematically and complicatedly screens and optimizes compounding of additives of different types and additives of the same type but with different compositions through a variety of simulation test methods, finally solves the key technical problems through laboratory simulation tests and M100 methanol engine durability tests, improves the synergistic effect between additives by introducing and adjusting the types and proportions of additives, and has better anti-wear performance and low-temperature cold starting performance compared with existing commercial products, meets the lubrication requirements of the M100 methanol engine, shows better anti-wear durability in the M100 methanol engine durability test, has better low-temperature cold starting performance in severely cold areas, and solves the use requirements of low viscosity and long oil change period of methanol engine oil. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a photo of the piston pressure surface;

[0025] Figure 2 This is a photo of the non-pressure-bearing surface of the piston;

[0026] Figure 3 Photo of the oil pan. DETAILED DESCRIPTION

[0027] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be construed as limiting the applicable scope of the present invention.

[0028] In order to screen the base oil and additive components, the present invention uses PDSC (induction period), wear spot diameter, low temperature dynamic viscosity and other test methods in the laboratory to evaluate the oxidation stability, wear resistance and low temperature fluidity of the oil. The simulation test conditions are: PDSC oxidation induction period setting temperature 210℃, template diameter 392N, low temperature dynamic viscosity test temperature -35℃.

[0029] Embodiment 1:

[0030] This embodiment provides a lubricating oil composition, the raw materials used for 100 kg of the lubricating oil composition and their masses are:

[0031] 0.5Kg of calcium salicylate with a base value of 265-295;

[0032] 0.5 kg of magnesium sulfonate with a base number of 395-430;

[0033] High molecular weight polyisobutylene succinimide (base value 46 mgKOH / g, nitrogen content 1.8%) 8.0 Kg;

[0034] Basic thiophosphorus dioctyl alkyl octyl salt (thiophosphorus ratio 1.80 zinc phosphorus ratio 1.1) 0.9Kg;

[0035] 1.0 kg of a mixture of p-diisooctyldiphenylamine and ester-type hindered phenol (VANLUBE BHC) (mass ratio 1:1);

[0036] 1.8 kg of a mixture of N,N-di(2-ethylhexyl)-methyl-1H-benzotriazole-1-methylamine and 2,5-dimercapto-1,3,4-thiadiazole (mass ratio 1:1);

[0037] Dibenzyl disulfide antiwear agent (sulfur content is 14%) 0.8Kg;

[0038] Ethylene-propylene copolymer viscosity modifier (RHY615) 4.0Kg;

[0039] Polymethacrylate 0.2Kg;

[0040] Dimethyl silicone antifoaming agent 0.005Kg;

[0041] CTL base oil (100℃ viscosity 3.8-4.2mm 2 / s)40.0Kg;

[0042] API Ⅲ hydrogenated base oil (100℃ viscosity 3.8-4.3mm 2 / s)42.195Kg;

[0043] The sulfur content of the lubricating oil composition of this embodiment is 0.28%, and the phosphorus content is 0.067%.

[0044] Embodiment 2:

[0045] This embodiment provides a lubricating oil composition, the raw materials used for 100 kg of the lubricating oil composition and their masses are:

[0046] 0.5Kg of calcium salicylate with a base value of 320-360;

[0047] 0.4 kg of magnesium alkyl salicylate with a base number of 400;

[0048] High molecular weight polyisobutylene succinimide (base value 48 mgKOH / g, nitrogen content 1.8%) 10.0 Kg;

[0049] Alkaline zinc dithiophosphate (sulfur-phosphorus ratio 1.9 zinc-phosphorus ratio 1.1) 1.0 kg;

[0050] 1.0 kg of a mixture of p-diisooctyldiphenylamine and ester-type hindered phenol (VANLUBE BHC) (mass ratio 1:1);

[0051] 2.0 kg of a mixture of N,N-di(2-ethylhexyl)-methyl-1H-benzotriazole-1-methylamine and 2,5-dimercapto-1,3,4-thiadiazole (mass ratio 1:1);

[0052] Dibenzyl disulfide antiwear agent (sulfur content is 14%) 0.5Kg;

[0053] Ethylene-propylene copolymer viscosity modifier (9230F) 4.0Kg;

[0054] Polymethacrylate 0.2Kg;

[0055] Dimethyl silicone antifoaming agent 0.005Kg;

[0056] CTL base oil (100℃ viscosity 3.8-4.2mm 2 / s)40.0Kg;

[0057] API Ⅲ hydrogenated base oil (100℃ viscosity 3.8-4.3mm 2 / s)40.395Kg;

[0058] The sulfur content of the lubricating oil composition of this embodiment is 0.27%, and the phosphorus content is 0.070%.

[0059] Embodiment 3:

[0060] This embodiment provides a lubricating oil composition, the raw materials used for 100 kg of the lubricating oil composition and their masses are:

[0061] The alkyl magnesium salicylate with a base number of 400 in the above Example 2 is replaced by magnesium sulfonate with a base number of 395-430, and the other components are of the same quality. The sulfur content of the lubricating oil composition of this example is 0.30%, and the phosphorus content is 0.068%.

[0062] Comparative Example 1:

[0063] This comparative example provides a lubricating oil composition, the raw materials used for 100 kg of which and their masses are:

[0064] The basic bis-octyl primary alkyl octyl thiophosphate in Example 1 was replaced by secondary alkyl zinc thiophosphate with a sulfur-to-phosphorus ratio of 2.1, and the other components were of the same quality. The lubricating oil composition of this comparative example had a sulfur content of 0.35% and a phosphorus content of 0.080%.

[0065] Comparative Example 2:

[0066] This comparative example provides a lubricating oil composition, the raw materials used for 100 kg of which and their masses are:

[0067] The basic zinc dithiophosphate in the above Example 1 is replaced by a secondary alkyl zinc salt of phosphorus sulfide with a sulfur-phosphorus ratio of 2.1, and the high molecular weight polyisobutylene succinimide is replaced by a boronized succinimide dispersant with a base value of 16, and the other components are of the same quality. The sulfur content of the lubricating oil composition of this comparative example is 0.33%, and the phosphorus content is 0.081%.

[0068] Comparative Example 3:

[0069] This comparative example provides a lubricating oil composition, the raw materials used for 100 kg of which and their masses are:

[0070] The CTL base oil in Example 1 was replaced with API III hydrogenated base oil (viscosity 5.8-6.2 mm at 100 °C). 2 / s), and the other components are the same in mass. The sulfur content of the lubricating oil composition of this comparative example is 0.28%, and the phosphorus content is 0.070%.

[0071] In order to verify the effect of the present invention, the engine lubricating oil prepared by the embodiment of the present invention was used to carry out laboratory simulation performance evaluation and engine bench test. The test results are shown in Table 1:

[0072] 1. Laboratory performance evaluation of lubricating oil compositions

[0073] Table 1 Lubricating oil composition performance evaluation results

[0074]

[0075] It can be seen from the data in Table 1 that the lubricating oil of the present invention has good oxidation resistance and wear resistance in the PDSC oxidation induction period and wear spot diameter simulation test evaluation. After the 120-hour M100 methanol engine endurance test, the wear spot diameter of the engine oil is below 0.8 mm, which is better than the wear spot diameter result of the commercial methanol engine oil after the 100-hour endurance test. In the -35°C low-temperature dynamic viscosity test, it showed excellent low-temperature fluidity. Example 1 completed the low-temperature cold start test of the methanol car within 5s at an outdoor temperature of -36°C, and achieved the use effect of starting within 3.5 seconds. Comparative Examples 1 and Comparative Examples 2 did not use basic zinc dithiophosphate (basic dioctyl alkyl octyl salt of sulfur phosphorus dioctyl salt). Although the PDSC performance of the engine oil was similar, the anti-wear performance of the engine oil decreased significantly after mixing with water, methanol and formic acid, and in Comparative Example 2, when high nitrogen high base value polymer polyisobutylene succinimide was not used, the wear test even showed serious results of biting. Comparative Example 3 does not use CTL4 base oil, resulting in a significant decrease in the low-temperature fluidity of the engine oil, and the excellent low-temperature fluidity effect of the present invention cannot be achieved.

[0076] 2. Disassembly and inspection of the lubricating oil composition of Example 1 after the engine bench test

[0077] After disassembly of the engine, Figure 1-Figure 3 The lubricating oil composition of the present invention exhibits excellent detergency, dispersibility and anti-wear properties in a methanol engine test.

Claims

1. An alcohol-resistant low-viscosity lubricating oil composition, which, based on the total mass of the lubricating oil composition being 100%, comprises: 0.6-1.0% metal detergent, 6.0-10.0% ashless dispersant, 0.5-2.0% antioxidant and antiwear agent, 1.0-2.0% metal deactivator, 0.2-1.0% extreme pressure antiwear agent, 3.0-5.0% viscosity index agent, 0.1-0.2% pour point depressant, 0.001-0.010% antifoaming agent, 30.0-50.0% CTL base oil, the balance is API III base oil; Wherein, the antioxidant and anti-wear agent includes alkaline zinc dithiophosphate, amine ashless antioxidant, and phenol ashless antioxidant; The metal deactivator includes a thiadiazole type metal deactivator and a tolyltriazole type metal deactivator; The extreme pressure anti-wear agent includes a thioether type extreme pressure anti-wear agent; In the antioxidant and anti-wear agent, the sulfur-phosphorus ratio of the alkaline zinc dithiophosphate is 1.8-1.9, zinc-phosphorus ratio is 1.1-1.2; In the extreme pressure anti-wear agent, the sulfur content of the thioether type extreme pressure anti-wear agent is 14.0-15.0%.

2. The lubricating oil composition according to claim 1, wherein The alkaline zinc dithiophosphate is basic zinc dioctyl alkyl dithiophosphate.

3. The lubricating oil composition according to claim 1 or 2, wherein Taking the weight of the antioxidant and anti-wear agent as 100%, the antioxidant and anti-wear agent comprises 40-60% alkaline zinc dithiophosphate, 20-30% amine ashless antioxidant, and 10-20% phenol ashless antioxidant; In the metal deactivator, the mass ratio of the thiadiazole type metal deactivator to the methylbenzotriazole type metal deactivator is 1:2-2:

1.

4. The lubricating oil composition according to claim 1, wherein The lubricating oil composition comprises: 0.7-1.0% metal detergent, 6.0-8.0% ashless dispersant, 0.5-1.8% antioxidant and antiwear agent, 1.0-2.0% metal deactivator, 0.2-0.8% extreme pressure and antiwear agent, 3.0-5.0% viscosity index agent, 0.1-0.2% pour point depressant, 0.001-0.010% antifoaming agent, 30.0-40.0% CTL base oil, the balance is API III base oil.

5. The lubricating oil composition according to claim 1, wherein The metal detergents include calcium salts and magnesium salts.

6. The lubricating oil composition according to claim 5, wherein The calcium salt includes calcium salicylate and / or calcium sulfonate, and the magnesium salt includes magnesium salicylate and / or magnesium sulfonate.

7. The lubricating oil composition according to claim 1, wherein The ashless dispersant includes polyisobutylene succinimide.

8. The lubricating oil composition according to claim 7, wherein The polyisobutylene succinimide has a nitrogen content of 1.8-2.2% and an alkali value of 46-55 mgKOH / g.

9. The lubricating oil composition according to claim 1, wherein The viscosity modifier includes ethylene propylene copolymer.

10. The lubricating oil composition according to claim 1, wherein The pour point depressant includes polymethacrylate.

11. The lubricating oil composition according to claim 1, wherein The anti-foaming agent includes dimethicone.

12. The lubricating oil composition according to claim 1, wherein The CTL base oil has a kinematic viscosity of 3.8-4.2 mm at 100°C. 2 / s of coal-based synthetic oil.

13. The lubricating oil composition according to claim 1, wherein The API III base oil has a kinematic viscosity of 3.8-4.3 mm at 100°C. 2 / s API III hydrocracking base oil.

14. The lubricating oil composition according to claim 1, wherein The lubricating oil composition has a sulfur content of 0.20-0.30 wt %, a phosphorus content of 0.06-0.07 wt %, a base number of 9.0-11.0 mgKOH / g, a sulfated ash content of 0.4-0.6 wt %, a four-ball wear spot diameter of less than 0.8 mm after a 120-hour endurance test of an M100 methanol engine in accordance with NB / SH / T 0189, and the methanol engine can be started within 3.5 seconds at -36°C.

15. Use of the lubricating oil composition according to any one of claims 1 to 14 in an M100 methanol passenger car engine.

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