Lubricating oil composition with long oil change period as well as preparation method and application of lubricating oil composition

Abstract

The invention belongs to the technical field of lubricating oil, and particularly relates to a lubricating oil composition with a long oil change period as well as a preparation method and application thereof. The lubricating oil composition disclosed by the invention is prepared from the following components based on the total weight of the lubricating oil composition: 0.8 to 1.8 percent of a metal detergent, 1.5 to 2.5 percent of an ashless dispersant, 0.5 to 1.3 percent of an antioxidant and antiwear agent, 0.1 to 0.8 percent of an auxiliary antioxidant, 5 to 10 percent of a viscosity index improver, 0.2 to 0.5 percent of a pour point depressant, 0.001 to 0.01 percent of an anti-foaming agent and the balance of base oil. The lubricating oil composition disclosed by the invention passes a program IIIE engine bench test in the SJ standard requirement, the performance meets the SJ index requirement, the test time is prolonged by 40% compared with the standard time, and the lubricating oil composition has excellent volatile resistance and less engine oil consumption and meets the requirement of a gasoline engine generator for a long oil change period of 150h in the actual use process.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of lubricating oil, and particularly relates to a lubricating oil composition with a long oil change period and a preparation method and application thereof. BACKGROUND

[0002] A gasoline generator is usually composed of a stator, a rotor, an end cover, a bearing and the like, and converts chemical energy into mechanical energy through fuel combustion, drives the rotor to rotate in the stator, and makes a cutting magnetic line movement, thereby generating an induced electromotive force, which is led out through a terminal and connected to a loop, so as to generate a current. The combustion of the fuel is carried out through a small engine, and long-term and stable operation of the engine plays a crucial role in continuous and persistent power supply.

[0003] The gasoline generator has a small oil loading amount and a long operation time, and requires little oil supplement during normal operation. Compared with a normal engine, the cooling system of the gasoline generator is air cooling, and the operation temperature of the gasoline generator with the air cooling system is higher than that of the engine with a water cooling system. The gasoline generator requires little oil consumption loss, high oxidation performance of the oil product and good cost performance, so as to meet the requirement of a long oil change period.

[0004] Chinese patent application CN104762125A discloses an engine lubricating oil. The weight fraction ratio of the lubricating oil components of the application is as follows: base oil 70-90 parts, multifunctional additive 0.01-5 parts, cleaning and dispersing agent 0.1-5 parts, viscosity index improver 0.1-5 parts, and pour point depressant 0.08-3 parts. The engine lubricating oil has good chemical stability, excellent antioxidant capacity, good anti-wear performance, good cleanliness, and reduces sludge and carbon deposition.

[0005] Chinese patent application CN112011389A discloses an engine lubricating oil composition. The composition is composed of a metal detergent, an ashless dispersant, an antioxidant and anti-wear agent, a friction-reducing agent, a viscosity index agent, a pour point depressant, an antifoaming agent and a base oil. The composition meets the API SN and ILSAC GF-5 standard requirements. The composition shows excellent energy-saving performance in the standard VID bench test, especially after aging of the oil product. The composition is also suitable for lubricating machine parts with high fuel economy requirements and long-term energy-saving performance.

[0006] Another Chinese invention patent application CN110317663A discloses a gasoline engine lubricating oil composition and a preparation method thereof. The gasoline engine lubricating oil composition of the invention comprises a phosphorus-containing compound, a boronized succinimide ashless dispersant, a salicylate detergent, a naphthylamine type antioxidant, zinc dialkyldithiophosphate, an organic molybdenum friction modifier, an OCP type viscosity index improver and a lubricating oil base oil. The lubricating oil composition of the invention has excellent biodegradability, high-temperature oxidation resistance, dispersing performance and friction reduction performance, and can meet the requirements of high-performance gasoline engine lubricating oil.

[0007] However, the above-mentioned lubricating oil composition and commercially available products meeting the requirements of SJ quality level have large oil consumption and more oil supplementing during use, thereby increasing the operation cost.

[0008] Therefore, there is an urgent need in the art to provide a lubricating oil composition suitable for the use requirements of a gasoline engine and having excellent oxidation resistance, dispersing performance, wear resistance and volatility resistance, so as to meet the requirements of long oil change period of the gasoline engine. SUMMARY

[0009] The present application aims at the problems existing in the prior art, and provides a lubricating oil composition with long oil change period, a preparation method and application thereof by screening each component in the lubricating oil composition and comprehensively and systematically researching the interaction and relationship between each component.

[0010] A lubricating oil composition comprises the following components based on the total weight of the lubricating oil composition: 0.8-1.8% of a metal detergent, 1.5-2.5% of an ashless dispersant, 0.5-1.3% of an antioxidant and anti-wear agent, 0.1-0.8% of an auxiliary antioxidant, 5-10% of a viscosity index improver, 0.2-0.5% of a pour point depressant, 0.001-0.01% of an anti-foaming agent, and the balance of a base oil.

[0011] Preferably, the lubricating oil composition comprises the following components based on the total weight of the lubricating oil composition: 1-1.5% of a metal detergent, 1.8-2.3% of an ashless dispersant, 0.7-1% of an antioxidant and anti-wear agent, 0.3-0.6% of an auxiliary antioxidant, 7-10% of a viscosity index improver, 0.2-0.4% of a pour point depressant, 0.001-0.006% of an anti-foaming agent, and the balance of a base oil.

[0012] Preferably, the metal detergent is selected from any two of an alkyl salicylate, an alkyl benzene sulfonate and a sulfided alkyl phenate.

[0013] Preferably, the alkyl salicylate is calcium alkyl salicylate or magnesium alkyl salicylate.

[0014] More preferably, the metal detergent is a mixture of alkylbenzene sulfonate and sulfurized alkyl phenate in a mass ratio of 3-6:1.

[0015] Preferably, the alkylbenzene sulfonate is calcium alkylbenzene sulfonate or magnesium alkylbenzene sulfonate, and the sulfurized alkyl phenate is calcium sulfurized alkyl phenate.

[0016] Preferably, the ashless dispersant is selected from any one or both of high molecular succinimide, polyisobutylene succinimide and polyisobutylene bisuccinimide.

[0017] More preferably, the ashless dispersant is high molecular succinimide or polyisobutylene succinimide.

[0018] Preferably, the antioxidant and antiwear agent is selected from any two of zinc dioctyl dithiophosphate, zinc bis-octyl dithiophosphate and zinc isopropyl isooctyl dithiophosphate.

[0019] Preferably, the auxiliary antioxidant includes amine antioxidant and phenolic antioxidant.

[0020] Preferably, the amine antioxidant is selected from any one or more of α-naphthylamine, diphenylamine and alkylated naphthylamine.

[0021] Preferably, the phenolic antioxidant is selected from any one or more of high molecular weight phenol, alkylated phenol and phenol derivative.

[0022] Preferably, the viscosity index improver is non-dispersive ethylene propylene copolymer, the pour point depressant is poly-α-olefin, and the antifoaming agent is dimethyl silicone oil.

[0023] Preferably, the base oil is hydrogenated base oil meeting any one or both of API Class II base oil standards.

[0024] The lubricating oil composition provided by the present application has an evaporation loss of not more than 10% and a PDSC (210℃, induction period) of not less than 25 min, based on the total mass of the composition.

[0025] The present application also provides a preparation method of the above lubricating oil composition, comprising the following steps: stirring the base oil, adding the antifoaming agent, mixing, and finally adding the metal detergent, ashless dispersant, antioxidant and antiwear agent, auxiliary antioxidant, viscosity index improver and pour point depressant, and mixing uniformly.

[0026] Preferably, the stirring temperature is 50-60℃, and the stirring time is 30-50 min.

[0027] Preferably, the mixing time is 1-2 h.

[0028] Preferably, the temperature of the mixing is 50-60℃, and the time of the mixing is 3-4h.

[0029] The application also provides the application of the above-mentioned lubricating oil composition or the lubricating oil composition prepared by the above-mentioned preparation method in a gasoline generator.

[0030] Compared with the prior art, the application has the following beneficial effects:

[0031] (1) The lubricating oil composition of the application passes the SJ standard requirement IIIE engine bench test, the performance meets the SJ index requirement, and the test time is increased by 40% compared with the standard time.

[0032] (2) The lubricating oil composition of the application has excellent volatility resistance, less oil consumption, and meets the 150h long oil change period requirement of the gasoline generator in actual use. DETAILED DESCRIPTION

[0033] It is worth noting that the raw materials used in the application are all ordinary commercially available products, wherein the calcium sulfidized alkyl phenol has a model number T115B; the calcium alkyl benzene sulfonate has a model number T106; the magnesium alkyl benzene sulfonate has a model number T107; the polyisobutylene succinimide has a model number T151; the high-molecular succinimide has a model number T161; the polyisobutylene bis-succinimide has a model number T152; the zinc dioctyl dithiophosphate has a model number T202; the zinc bis-octyl dithiophosphate has a model number T203; the zinc isopropyl dithiophosphate has a model number T205; the diphenylamine has a model number L57; the alkylated naphthylamine has a model number T531; the alpha-naphthylamine has a model number L06; the alkylated phenol has a model number VDTB; the high-molecular weight phenol has a model number L135; the phenol derivative has a model number L130; and the alpha-phenylamine has a model number L01.

[0034] Example 1

[0035] A long oil change period lubricating oil composition, with a total weight of 100kg, is composed of the following components:

[0036] Metallic detergent: calcium alkyl benzene sulfonate 0.6kg, calcium sulfidized alkyl phenol 0.2kg;

[0037] Ashless dispersant: polyisobutylene succinimide 2.5kg;

[0038] Anti-oxidation and anti-wear agent: zinc dioctyl dithiophosphate 0.4kg, zinc isopropyl dithiophosphate 0.4kg;

[0039] Auxiliary antioxidant: diphenylamine 0.25kg, alkylated phenol 0.25kg;

[0040] Viscosity index improver: ethylene propylene copolymer 8.0kg;

[0041] Pour point depressant: poly-alpha-olefin 0.3 kg;

[0042] Antifoam agent: dimethyl silicone oil 0.005 kg;

[0043] Base oil: API Group II hydrogenated base oil 87.095 kg.

[0044] A method for preparing a long oil change period lubricating oil composition, comprising the following steps: adding a required amount of base oil into a stainless steel mixing kettle with mechanical stirring, heating to 50°C and stirring for 30 min, then adding a required amount of antifoam agent into the mixing kettle and continuing to stir for 2 h; then sequentially adding a required amount of metal detergent, ashless dispersant, antioxidant and antiwear agent, auxiliary antioxidant, viscosity index improver and pour point depressant into the mixing kettle, and continuing to stir at 50°C for 4 h until uniform, thereby obtaining the lubricating oil composition.

[0045] Example 2

[0046] A long oil change period lubricating oil composition, with a total weight of 100 kg, comprising the following components:

[0047] Metal detergent: calcium alkylbenzene sulfonate 1.2 kg, calcium sulfonated alkylphenol 0.2 kg;

[0048] Ashless dispersant: high molecular weight succinimide 2.0 kg;

[0049] Antioxidant and antiwear agent: zinc dioctyl dithiophosphate 0.5 kg, bis (octyl) zinc dithiophosphate 0.3 kg;

[0050] Auxiliary antioxidant: alkylated naphthylamine 0.3 kg, high molecular weight phenol 0.1 kg;

[0051] Viscosity index improver: ethylene-propylene copolymer 7.0 kg;

[0052] Pour point depressant: poly-alpha-olefin 0.2 kg;

[0053] Antifoam agent: dimethyl silicone oil 0.003 kg;

[0054] Base oil: API Group II hydrogenated base oil 88.197 kg.

[0055] A method for preparing a long oil change period lubricating oil composition, comprising the following steps: adding a required amount of base oil into a stainless steel mixing kettle with mechanical stirring, heating to 50°C and stirring for 30 min, then adding a required amount of antifoam agent into the mixing kettle and continuing to stir for 2 h; then sequentially adding a required amount of metal detergent, ashless dispersant, antioxidant and antiwear agent, auxiliary antioxidant, viscosity index improver and pour point depressant into the mixing kettle, and continuing to stir at 50°C for 4 h until uniform, thereby obtaining the lubricating oil composition.

[0056] Example 3

[0057] A long drain lubricating oil composition, total weight 100 kg, consists of:

[0058] Metal detergent: magnesium alkyl benzene sulfonate 1.5 kg, calcium sulfonated alkyl phenate 0.3 kg;

[0059] Ashless dispersant: polyisobutylene succinimide 0.5 kg, high molecular succinimide 1.0 kg;

[0060] Anti-oxidant and anti-wear agent: zinc bis-octyl dithiophosphate 0.4 kg, zinc isopropyl dithiophosphate 0.6 kg;

[0061] Auxiliary antioxidant: alpha aniline 0.1 kg, phenolic derivative 0.2 kg;

[0062] Viscosity index improver: ethylene propylene copolymer 10.0 kg;

[0063] Pour point depressant: poly-alpha-olefin 0.5 kg;

[0064] Antifoam agent: dimethyl silicone oil 0.01 kg;

[0065] Base oil: API Group II hydrogenated base oil 84.89 kg.

[0066] A method for preparing a long drain lubricating oil composition, the steps are as follows: add the required amount of base oil into a stainless steel mixing kettle with mechanical stirring, heat to 60 °C and stir for 40 min, then add the required amount of antifoam agent to the mixing kettle and continue stirring for 1 h; then add the required amount of metal detergent, ashless dispersant, anti-oxidant and anti-wear agent, auxiliary antioxidant, viscosity index improver and pour point depressant to the mixing kettle in turn, continue to stir at 60 °C for 3 h until uniform, and then obtain.

[0067] Example 4

[0068] A long drain lubricating oil composition, total weight 100 kg, consists of:

[0069] Metal detergent: magnesium alkyl benzene sulfonate 1.0 kg, calcium sulfonated alkyl phenate 0.3 kg;

[0070] Ashless dispersant: polyisobutylene succinimide 2.2 kg;

[0071] Anti-oxidant and anti-wear agent: zinc butyl octyl dithiophosphate 0.48 kg, zinc bis-octyl dithiophosphate 0.82 kg;

[0072] Auxiliary antioxidant: alkylated naphthylamine 0.025 kg, alkylated phenol 0.075 kg;

[0073] Viscosity index improver: ethylene propylene copolymer 5.0 kg;

[0074] Pour point depressant: poly-alpha-olefin 0.4 kg;

[0075] Antifoaming agent: dimethyl silicone oil 0.001 kg;

[0076] Base oil: API Group II hydrogenated base oil 89.699 kg.

[0077] A method for preparing a long oil change period lubricating oil composition, the steps are as follows: a required amount of base oil is added to a stainless steel mixing kettle with mechanical stirring, heated to 60°C and stirred for 40 min, then a required amount of antifoaming agent is added to the mixing kettle and continues to stir for 1 h; then a required amount of metal detergent, ashless dispersant, anti-oxidation and anti-wear agent, auxiliary antioxidant, viscosity index improver and pour point depressant are sequentially added to the mixing kettle, and continues to stir at 60°C for 3 h until uniform, and it is obtained.

[0078] Comparative Example 1

[0079] The same as Example 2, the only difference is that the components are different.

[0080] A long oil change period lubricating oil composition, the total weight is 100 kg, which is composed of the following components:

[0081] Metal detergent: magnesium alkylbenzenesulfonate 1.2 kg, calcium sulfonated alkylphenol 0.2 kg;

[0082] Ashless dispersant: high molecular succinimide 2.0 kg;

[0083] Anti-oxidation and anti-wear agent: zinc butyloctyl dithiophosphate 0.5 kg, zinc dioctyl dithiophosphate 0.3 kg;

[0084] Viscosity index improver: ethylene propylene copolymer 7.0 kg;

[0085] Pour point depressant: poly-alpha-olefin 0.2 kg;

[0086] Antifoaming agent: dimethyl silicone oil 0.003 kg;

[0087] Base oil: API Group II hydrogenated base oil 88.597 kg.

[0088] A method for preparing a long oil change period lubricating oil composition, the steps are as follows: a required amount of base oil is added to a stainless steel mixing kettle with mechanical stirring, heated to 50°C and stirred for 30 min, then a required amount of antifoaming agent is added to the mixing kettle and continues to stir for 2 h; then a required amount of metal detergent, ashless dispersant, anti-oxidation and anti-wear agent, viscosity index improver and pour point depressant are sequentially added to the mixing kettle, and continues to stir at 50°C for 4 h until uniform, and it is obtained.

[0089] Comparative Example 2

[0090] The same as Example 2, the only difference is the component.

[0091] A long drain lubricating oil composition, total weight 100 kg, consists of the following components:

[0092] Metal detergent: magnesium alkyl benzene sulfonate 1.5 kg;

[0093] Ashless dispersant: polyisobutylene succinimide 0.5 kg, high molecular weight succinimide 1.5 kg;

[0094] Anti-oxidant and anti-wear agent: butyl octyl zinc dithiophosphate 0.5 kg, bis octyl zinc dithiophosphate 0.3 kg;

[0095] Auxiliary antioxidant: alkylated naphthylamine 0.2 kg, high molecular weight phenol 0.1 kg;

[0096] Viscosity index improver: ethylene propylene copolymer 7.0 kg;

[0097] Pour point depressant: poly alpha-olefin 0.3 kg;

[0098] Antifoam agent: dimethyl silicone oil 0.005 kg;

[0099] Base oil: API Group II hydrogenated base oil 88.095 kg.

[0100] A method for preparing a long drain lubricating oil composition, the steps are as follows: add the required amount of base oil to a stainless steel mixing kettle with mechanical stirring, heat to 50°C and stir for 30 min, then add the required amount of antifoam agent to the mixing kettle and continue stirring for 2 h; then add the required amount of metal detergent, ashless dispersant, anti-oxidant and anti-wear agent, auxiliary antioxidant, viscosity index improver and pour point depressant to the mixing kettle in turn, continue to stir at 50°C for 4 h to uniform, and then obtain.

[0101] Comparative Example 3

[0102] The same as Example 2, the only difference is the component ratio.

[0103] A long drain lubricating oil composition, total weight 100 kg, consists of the following components:

[0104] Metal detergent: magnesium alkyl benzene sulfonate 1.0 kg, calcium sulfonated alkyl phenate 0.5 kg;

[0105] Ashless dispersant: high molecular weight succinimide 2.3 kg;

[0106] Anti-oxidant and anti-wear agent: zinc dioctyl dithiophosphate 0.25 kg, bis (cyclohexyl) dithiophosphate 0.15 kg;

[0107] Co-antioxidant: alkylated naphthylamine 0.15 kg, high molecular weight phenol 0.05 kg

[0108] Viscosity index improver: ethylene propylene copolymer 7.0 kg;

[0109] Pour point depressant: poly-alpha-olefin 0.2 kg;

[0110] Anti-foaming agent: dimethyl silicone oil 0.003 kg;

[0111] Base oil: API Group II hydrogenated base oil 88.397 kg.

[0112] A method for preparing a long oil change period lubricating oil composition, comprising the following steps: adding a required amount of base oil into a stainless steel mixing kettle with mechanical stirring, heating to 50℃ and stirring for 30 min, then adding a required amount of anti-foaming agent into the mixing kettle and continuing to stir for 2 h; then sequentially adding a required amount of metal detergent, ashless dispersant, anti-oxidant and anti-wear agent, co-antioxidant, viscosity index improver and pour point depressant into the mixing kettle, and continuing to stir at 50℃ for 4 h until uniform, thereby obtaining the long oil change period lubricating oil composition.

[0113] Test Example 1

[0114] The long oil change period lubricating oil compositions prepared according to Example 1-4 and Comparative Examples 1-3 were subjected to performance tests, and the results are shown in Table 1.

[0115] The anti-volatility performance of the lubricating oil composition was evaluated according to NB / SH / T0059-2010—Determination of Evaporation Loss of Lubricating Oil—Noack Method.

[0116] The detergency of the lubricating oil composition was evaluated according to NB / SH / T0906-2015—Test Method for Thermal Stability of Engine Oil—Hot Tube Test Method (test temperature 280℃, compressed air at a certain flow rate and test oil at a certain speed pass through the test tube, test duration 16 h, and the glass tube after the test was scored).

[0117] The oil sludge dispersibility (SDT value) of the lubricating oil composition was evaluated according to NB / SH / T 0618—Determination of Dispersancy of In-Service Engine Oil (Filter Paper Spot Method) (mixing the oil and oil sludge at a fixed ratio, stirring at a temperature of 150℃ for 1.5 h, cooling to room temperature, then dropping one drop onto filter paper using a specific glass rod, fixing on a test rack, and calculating the oil ring and oil sludge ring after 16 h of dispersion of the oil sludge mixture).

[0118] The lubricating oil composition was evaluated for antioxidation performance (test temperature 210°C) according to SH / T 0719 - Determination of oxidation induction period of lubricating oils (pressure differential scanning calorimetry).

[0119] As can be seen from Table 1, the long drain lubricating oil composition prepared in Example 1-4 of the present application has good volatility resistance, detergency, oil sludge dispersing performance and oxidation stability compared with Comparative Examples 1-3. And the performance index test of the lubricating oil composition prepared in Example 2 is the best, and the subsequent test will be further tested for the lubricating oil composition prepared in Example 2.

[0120] Table 1 Performance test

[0121]

[0122]

[0123] Test Example 2

[0124] The long drain lubricating oil composition prepared in Example 2 of the present application was subjected to engine bench test, and the test method referred to SH / T 0758-2005 - Evaluation of high temperature oxidation and anti-wear performance of engine oils (Procedure III E method), and the results were shown in Table 2.

[0125] As can be seen from Table 2, the lubricating oil composition prepared in Example 2 of the present application passed the SJ program MS IIIE engine bench test, and had good oxidation resistance, anti-wear performance and detergency.

[0126] Table 2 Results of Procedure IIIE bench test of the lubricating oil composition prepared in Example 2

[0127] Item Limit Example 2 Hours to 375% viscosity increase ≥64 90.8 Engine sludge average score ≥9.2 9.8 Piston skirt lacquer average score ≥8.9 9.2 Oil ring land deposit average score ≥3.5 5.3 Ring stickiness (oil related) No No Tappet stickiness No No Cam or tappet scuffing No No Cam plus tappet wear average, mm ≤0.03 0.02 Cam plus tappet wear maximum, mm ≤0.064 0.034

[0128] Test Example 3

[0129] The long drain lubricating oil composition prepared in Example 2 of the present application and the competitive product (OEM in-use oil) were subjected to 150h use test in original equipment manufacturer (OEM), and no supplement was added during the test, and the related indexes of the lubricating oil composition and the competitive product after 150h test were tested, and the results were shown in Table 3.

[0130] The kinematic viscosity performance of the used lubricating oil composition and the competitive product was evaluated according to GB T 265-1988 - Determination of kinematic viscosity of petroleum products and calculation of dynamic viscosity.

[0131] The base number of the used lubricating oil composition and the competitive product was determined according to SH T 0251-1993 - Determination of base number of petroleum products.

[0132] The used lubricating oil composition and the competitor are subjected to acid value determination according to GBT 7304-2014—Determination of acid number of petroleum products-potentiometric titration method.

[0133] The used lubricating oil composition and the competitor are subjected to n-pentane insoluble content determination according to GB / T 8926-2012—Determination of insoluble matter in lubricating oils in service.

[0134] The used lubricating oil composition and the competitor are subjected to moisture determination according to GB / T 260—Determination of moisture in petroleum products.

[0135] The used lubricating oil composition and the competitor are subjected to partial metal element determination according to GB / T 17476-2023—Determination of multiple elements in lubricating oils and base oils.

[0136] The used lubricating oil composition and the competitor are subjected to oxidation value and nitration value determination according to NB / SH / T 0853—In-service lubricating oil condition detection method (Fourier transform infrared spectroscopy trend analysis method).

[0137] As can be seen from Table 3, compared with the competitor, the lubricating oil composition of Example 2 has good oxidation resistance and anti-wear performance, and can meet the 150h oil change period requirement of the gasoline generator, thereby reducing the operation cost.

[0138] Table 3 Test results of relevant indexes of the used lubricating oil composition prepared in Example 2 and the competitor

[0139] Item Competitor Example 2 100 °C kinematic viscosity / (mm 2 / s) 15.47 14.54 Base number / (mg KOH / g) 8.35 6.0 Acid number / (mg KOH / g) 2.29 2.98 n-Pentane insolubles / % / 0.4 Moisture / % / 0.07 Aluminium content / ppm 91.67 36 Iron content / ppm 848.5 104 Copper content / ppm 170.8 4.3 Silicon content / ppm 25.46 68 Oxidation number / (A / 0.1 mm) 8.35 8 Nitration number / (A / 0.1 mm) 6.45 7

[0140] Finally, it should be noted that the above content is only used to illustrate the technical solutions of the present application, and is not a limitation on the protection scope of the present application. Simple modifications or equivalent replacements of the technical solutions of the present application made by those skilled in the art do not deviate from the essence and scope of the technical solutions of the present application.

Claims

1. A lubricating oil composition characterized in that, The lubricating oil composition comprises the following components by weight: 0.8-1.8% of metal detergent, 1.5-2.5% of ashless dispersant, 0.5-1.3% of antioxidant and anti-wear agent, 0.1-0.8% of auxiliary antioxidant, 5-10% of viscosity index improver, 0.2-0.5% of pour point depressant, 0.001-0.01% of anti-foaming agent, and base oil to make up to 100%.

2. The lubricating oil composition of claim 1, wherein The lubricating oil composition comprises the following components by weight: 1-1.5% of metal detergent, 1.8-2.3% of ashless dispersant, 0.7-1% of antioxidant and anti-wear agent, 0.3-0.6% of auxiliary antioxidant, 7-10% of viscosity index improver, 0.2-0.4% of pour point depressant, 0.001-0.006% of anti-foaming agent, and base oil to make up to 100%.

3. The lubricating oil composition of claim 1 or 2, wherein The metal detergent is selected from any two of alkyl salicylate, alkyl benzene sulfonate and sulfidized alkyl phenate, and the alkyl salicylate is calcium alkyl salicylate or magnesium alkyl salicylate.

4. The lubricating oil composition of claim 3, wherein, The metal detergent is a mixture of alkyl benzene sulfonate and sulfidized alkyl phenate in a mass ratio of 3-6:

1.

5. The lubricating oil composition of claim 4, wherein, The alkyl benzene sulfonate is calcium alkyl benzene sulfonate or magnesium alkyl benzene sulfonate, and the sulfidized alkyl phenate is calcium sulfidized alkyl phenate.

6. The lubricating oil composition of claim 1 or 2, wherein The ashless dispersant is selected from any one or two of high molecular succinimide, polyisobutylene succinimide and polyisobutylene bis-succinimide.

7. The lubricating oil composition of claim 1 or 2, wherein The antioxidant and anti-wear agent is selected from any two of zinc dioctyl dithiophosphate, bis-octyl dithiophosphate and isopropyl isooctyl dithiophosphate.

8. The lubricating oil composition of claim 1 or 2, wherein The auxiliary antioxidant comprises amine antioxidant and phenolic antioxidant.

9. The lubricating oil composition of claim 8, wherein, The amine antioxidant is selected from any one or more of α-naphthylamine, diphenylamine and alkylated naphthylamine.

10. The lubricating oil composition of claim 8, wherein, The phenolic antioxidant is selected from any one or more of high molecular weight phenol, alkylated phenol and phenol derivative.

11. The lubricating oil composition of claim 1 or 2, wherein The viscosity index improver is ethylene-propylene copolymer, the pour point depressant is poly-α-olefin, and the anti-foaming agent is dimethyl silicone oil.

12. The lubricating oil composition of any of claims 1-11, wherein, The base oil is hydrogenated base oil meeting any one or both of API Class II base oil standard requirements.

13. A process for the preparation of a lubricating oil composition as claimed in any one of claims 1 to 12, characterised in that, The method comprises the following steps: stirring base oil, adding anti-foaming agent, mixing, and finally adding metal detergent, ashless dispersant, antioxidant and anti-wear agent, auxiliary antioxidant, viscosity index improver and pour point depressant, and mixing uniformly.

14. The method of claim 13, wherein, The stirring temperature is 50-60°C, the stirring time is 30-50 min, and the mixing time is 1-2 h.

15. The preparation method according to claim 13, characterized in that, The mixing temperature is 50-60°C, and the mixing time is 3-4 h.

16. Use of the lubricating oil composition of any one of claims 1-12 or prepared by the method of any one of claims 13-15 in a gasoline engine.

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