Long-mileage gas engine lubricating oil and preparation method thereof

Abstract

The invention discloses long-mileage gas engine lubricating oil and a preparation method thereof. The lubricating oil takes class III paraffin-based synthetic oil as base oil, and is compounded with an antioxidant and antiwear agent, a metal detergent, an ashless dispersant, an antifriction and antiwear agent, a viscosity index improver and a pour point depressing emulsifier. Through the synergistic effect of multiple components, the oxidation resistance, nitrification resistance, wear resistance and friction reduction performance are enhanced, medium-low ash content, low sulfur and low phosphorus are achieved, oil and water are emulsified without layering, and the requirement for the oil change period of 100 thousand kilometers of a gas engine is met. The preparation method comprises the steps of sol preparation, compounding and blending, and the process is simple and controllable.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lubricating oil, in particular to a long-range gas engine lubricating oil and a preparation method thereof. BACKGROUND

[0002] The gas engine has the characteristics of high combustion chamber temperature, high nitrogen oxide content in exhaust gas and difficult lubrication, namely "two high and one difficult". The combustion chamber temperature is high. Secondly, natural gas engines are usually flat combustion, unlike lean combustion, there is more air to dilute and cool, resulting in a higher combustion chamber temperature of the gas engine than that of the traditional internal combustion engine, and the exhaust gas temperature is about 165-235℃ higher than that of diesel engine. At high temperature, ordinary oil will oxidize and deteriorate too quickly, causing lubrication failure and early wear of parts. The nitrogen oxide content in the exhaust gas is high. Although CNG and LNG are clean fuels, in the high temperature environment of the combustion chamber, nitrogen and oxygen will react to generate more nitrogen oxides, resulting in an increase in the content of nitrogen oxides in the exhaust gas, causing oil oxidation and nitration, increasing the viscosity of the oil, increasing the oil sludge and deposits, and causing the lubricating performance of the oil to decrease, leading to increased engine wear. Difficult to lubricate. High temperature is not conducive to the formation of a lubricating oil film. In addition, since diesel is sprayed into the cylinder in the form of small droplets, it can lubricate and cool the valve, valve seat and other parts, while the gas engine fuel CNG / LNG enters the cylinder in the form of gas, making the engine valve seat and other parts dry and without lubrication, which can cause wear of the above-mentioned parts. At the same time, it is found that the water vapor generated by combustion cannot be discharged in winter, causing water vapor to condense into water and flow into the oil pan, resulting in white emulsion of the oil, freezing, clogging of the filter screen, oil-water stratification, difficulty in cold start, and corrosion and rust of the engine.

[0003] The particularity of the gas engine has led to the lack of a unified standard and a unified bench evaluation method for a long time. Each natural gas engine manufacturer mainly formulates its own OEM standard through specific test tests according to the working condition characteristics of its own natural gas engine. Among the above-mentioned many OEM specifications, the Cummins CES20092 specification is the most representative OEM specification for natural gas engine oil, which has the most complete indicators and the most stringent requirements.

[0004] The oil change period of the domestic mainstream OEM diesel engine oil has reached 100,000 kilometers, while the oil change period of the gas engine oil is only 20,000 to 60,000 kilometers. There is no 100,000 kilometer oil change period technology for domestic gas engine oil. The main performance of the gas engine oil developed is: first, control of oxides and nitrates, control of wear, reduction of combustion chamber deposits, reduction of spark plug blockage, reduction of piston deposits, and consideration of catalyst compatibility, the oil is required to be low ash 0.4%-0.9%, low sulfur and phosphorus content, and the oil and water emulsion is required not to be stratified.

[0005] The disclosure of the foregoing Background Art is given solely for the purpose of aiding in the understanding of the inventive concept and technical solutions of the present application, and it does not necessarily belong to the prior art of the present patent application. The foregoing Background Art should not be used to evaluate the novelty and inventiveness of the present application without explicit evidence that the above-mentioned content has been disclosed before the filing date of the present patent application. SUMMARY

[0006] The present application is mainly aimed at providing a long-mileage gas engine lubricating oil and a preparation method, so as to solve the technical problems of the existing prior art, such as the oxidation and deterioration of engine oil due to high combustion chamber temperature, high nitrogen oxide content in tail gas, difficult lubrication, corrosion and rust caused by oil-water separation during low-temperature cold start, and short oil change cycle of the gas engine.

[0007] In order to achieve the above technical purpose, the present application adopts the following technical solutions:

[0008] A long-mileage gas engine lubricating oil, based on the total weight of the gas engine oil composition, the gas engine oil composition comprises, by mass content: antioxidant and anti-wear agent: 1%-5%; metal detergent: 1.0%-5.0%; ashless dispersant 1.0%-15%; friction-reducing anti-wear agent: 0.1%-0.5%; viscosity index improver: 5.0%-15.0%; pour point depressant: 0.1%-1.5%; the rest is Group III base oil.

[0009] Preferably, the present application can also have the following technical features:

[0010] Preferably, the pour point depressant is V6-850, the antioxidant and anti-wear agent is zinc dialkyldithiocarbamate, oligomer synthetic aromatic amine type antioxidant, long-chain alkyl hindered phenol, and the mass ratio is (0.5-1.0):(1.0-2.0):(1.0-2.0).

[0011] Preferably, the metal detergent is magnesium alkylsalicylate and calcium sulfide alkylphenol mixed in a mass ratio of (0.5-2.0):(0.5-2.0), the ashless dispersant is a boronized polyisobutylene succinimide type dispersant, the friction-reducing anti-wear agent is molybdate, and the viscosity index improver is OCP viscosity improver.

[0012] Preferably, the pour point depressant is polymethyl acrylate, and the base oil is selected from Group III paraffin-based synthetic oil.

[0013] Preferably, the oligomer synthesis of arylamine type antioxidant is alkylated N-phenyl-α-naphthylamine and alkylated diphenylamine in polyol ester solvent, and by inert gas nitrogen, under the condition of reaction temperature of 100-190℃, the reaction raw material is initiated by initiator to occur chemical reaction, after reaction of 6-12h, it is obtained by reduced pressure distillation, red-brown sticky oligomer synthesis of amine type antioxidant.

[0014] Preferably, the structure of the long chain alkyl thio hindered phenol is preferably as shown in formula I:

[0015]

[0016] Formula I

[0017] Preferably, the alkyl magnesium salicylate is a specific type of alkyl salicylate, and the structure of the alkyl salicylate is preferably as shown in formula II:

[0018] ;

[0019] Formula II

[0020] Wherein, R is an alkyl group containing 10-20 carbon atoms, M is Ca or Mg, m, n are positive integers not equal to zero;

[0021] The sulfided calcium alkyl phenate is a specific type of sulfided alkyl phenate, and the structure of the sulfided alkyl phenate is preferably as shown in formula III:

[0022] ;

[0023] Formula III

[0024] In the formula, R2 is an alkyl group containing 10-24 carbon atoms, M is Ca or Mg, m2, n2, x are positive integers not equal to zero.

[0025] Preferably, the structure of the boronized polyisobutylene succinimide dispersant is as shown in formula IV:

[0026] ;

[0027] Formula IV

[0028] Wherein, PIB is polyisobutylene, the molecule is 900-1300, r is a positive integer not equal to zero;

[0029] In the formula, R=C n H 2n+1 , n=4-12;

[0030] The pour point depressant emulsifier is a poly methacrylate, and the structure is as shown in formula V:

[0031]

[0032] Formula V

[0033] In the formula, R = C n H 2n+1 , n = 10-20.

[0034] Preferably, the method for preparing the long-range gas engine lubricating oil comprises the following steps:

[0035] 1) Sol: according to the formula proportion, first mix the dry gel form OCP adhesive block with a proper amount of base oil, the mass ratio of OCP adhesive and base oil is 1:10; heat to 128-138℃ and stir, dissolve, stand for 6-8h, get product a;

[0036] 2) Compound: put product a and the remaining base oil into a blending kettle, according to the formula proportion, add dispersant, antioxidant and anti-wear agent, detergent, anti-wear agent, start stirring, heat to 58-68℃ and keep, continue stirring for 3-6h, get product b;

[0037] 3) Blending: finally add the pour point depressant emulsifier in product b, the stirring temperature is 40-50℃, continue stirring for 3-6h.

[0038] The beneficial effects of the present application compared with the prior art include:

[0039] (1) The oligomer synthesis arylamine antioxidant is synthesized by the reaction of alkylated N-phenyl-alpha-naphthylamine and alkylated diphenylamine, which combines the advantages of both, the benzene ring and naphthalene ring in the structural formula form a larger π-electron conjugated system, the N-H bond and oxygen free radical reaction ability is enhanced, the electron delocalization effect makes the whole molecule form a stable free radical after losing H, thereby reducing the oil oxidation rate, and the monomer has higher thermal stability (naphthalene ring conjugation is enhanced), and the alkyl chain (such as C8-C12) on the structure provides good oil solubility, avoids the problem of monomer oxidation and precipitation, and has the function of regenerating antioxidant. The oligomer synthesis arylamine antioxidant overcomes the defects of monomer, has higher thermal decomposition temperature and oxidation stability, has more outstanding antioxidant performance than conventional antioxidant, and can meet the antioxidant performance requirements of oil products under high temperature working conditions.

[0040] (2) Due to the limitation of phosphorus in the aftertreatment system, the dosage of phosphorus-containing additives needs to be controlled, and additives with peroxide decomposition function need to be supplemented. The synthetic base oil lacks natural sulfur components, and the synthetic base oil has good sensitivity to sulfur-containing antioxidants. Therefore, long-chain alkyl sulfur hindered phenol antioxidants are preferred. The sulfur hindered phenol antioxidant containing one thioether group antioxidant functional group can terminate the oxidation reaction of hydrocarbon molecular chain by reacting with ROO· through phenolic hydroxyl group homolysis dehydrogenation, and can decompose ROOH into ROH through the thioether group, thereby generating a self-synergistic antioxidant effect, so that the sulfur hindered phenol antioxidant has better antioxidant activity than the sulfur-free phenol type. The introduction of a C9 alkyl long chain at the para position of the hydroxyl group can increase the relative molecular mass and reduce the volatility, and can control the solubility and volatility of the antioxidant and improve the anti-aging efficiency. Long-chain alkyl sulfur hindered phenol has the dual functions of inhibiting oxidation chain reaction of primary antioxidant and decomposing hydroperoxide of auxiliary antioxidant.

[0041] The long-chain alkyl sulfur hindered phenol antioxidant and the oligomer synthetic aromatic amine antioxidant have good synergistic effect. The reaction speed of the oligomer synthetic aromatic amine antioxidant with alkyl peroxide radical is higher than that of the long-chain alkyl sulfur hindered phenol, and the long-chain alkyl sulfur hindered phenol provides hydrogen atoms for the regeneration of amine for the oligomer synthetic aromatic amine radical, that is, through the transfer of active hydrogen (H), the long-chain alkyl sulfur hindered phenol antioxidant with relatively weak activity is sacrificed, so that the oligomer synthetic aromatic amine antioxidant with relatively strong activity can be regenerated.

[0042] (3) As a peroxide decomposer, zinc dialkyldithiocarbamate (ZnDDC) has strong nucleophilicity of sulfur atoms in the molecule, which can attack and decompose organic hydroperoxide produced in the oxidation process of lubricating oil, and convert it into relatively inert substances such as alcohols, while itself is oxidized into various complex sulfur-containing oxidation products, interrupting the key link (ROOH decomposition produces new free radicals RO· and ROO·) in the free radical chain reaction, significantly slowing down the further oxidation of the oil. Zinc dialkyldithiocarbamate (ZnDDC) can form an adsorption film or a reaction film on the surface of metals (such as copper and iron), preventing metal ions (especially copper ions) from dissolving into the oil. Dissolved metal ions are strong oxidation catalysts (catalyzing the decomposition of ROOH), so passivating the metal surface indirectly inhibits the oxidation process.

[0043] (4) The long-chain alkyl sulfur hindered phenol and the oligomer synthetic aromatic amine antioxidant as free radical terminators react with peroxide radicals to prevent the transfer and growth of free radical chains, while zinc dialkyldithiocarbamate (ZnDDC) as a hydroperoxide decomposer prevents chain branching reactions, both of which work together to break the chain growth and chain branching reactions of the chain reaction, avoiding the mutual causality and mutual catalytic cyclic reaction between free radicals and peroxides.

[0044] (5) Molybdate (MoDTC) and zinc dialkyldithiocarbamate (ZnDDC) have a synergistic effect in reducing engine wear. Zinc dialkyldithiocarbamate (ZnDDC) can provide a sulfur source, and the two complement each other to form a film, building a double-layer protective barrier. Molybdate (MoDTC) and long-chain alkyl hindered phenolic antioxidants and oligomer synthetic aromatic amine antioxidants have a synergistic effect in oxidation resistance. The film generated by molybdate (MoDTC) has super-slip and reduces friction, providing a sliding interface in the upper layer, reducing friction heat, and reducing the friction coefficient of the engine friction pair. In tribology, it has a synergistic effect of catalytic activation and film regeneration, reducing the oxidation rate of antioxidants at high temperatures. The four-component synergistic system of long-chain alkyl hindered phenolic antioxidants, oligomer synthetic aromatic amine antioxidants, zinc dialkyldithiocarbamate (ZnDDC), and molybdate (MoDTC) has excellent oxidation resistance, friction reduction, and wear resistance.

[0045] (6) Detergent complex (high-alkali-value alkyl magnesium salicylate + high-alkali-value sulfated alkyl calcium phenate): High-alkali-value alkyl magnesium salicylate can instantaneously neutralize explosive acid, and its salicylic acid aromatic ring structure can adsorb soot, promote the crystallization of deposits, form a dense metal soap film to isolate oxidation products, promote the decomposition of hydroperoxide, and block the oxidation chain reaction. It can also generate a friction polymerization film under boundary lubrication to repair micro scratches. High-alkali-value sulfated alkyl calcium phenate can provide long-term neutralization protection, and its CaCO3 glue core can physically abrade the deposition layer. The sulfated alkyl phenol can inhibit high-temperature polymerization, and the phenolic radical can terminate the oxidation chain reaction. It can also transfer part of the heat, reducing the ignition point of the micellar CaCO3, thereby reducing the risk of low-speed pre-ignition. Under boundary lubrication, the sulfated group decomposes to form an FeS anti-wear film. The synergistic effect of the two enhances acid neutralization capacity, breaks through high-temperature detergency, and synergistically improves oxidation resistance and wear resistance.

[0046] (7) Pour point depressant emulsifier (V6-850 polymethacrylate): Oil and water separation can cause severe mechanical wear, corrosion, and rust, and can also lead to low-temperature cold start difficulties. To solve these problems, the emulsifier used is a polar group-containing polymethacrylate (PMA) high molecular polymer. It can interact with water through hydrogen bonds, reduce interfacial tension, inhibit water droplet coalescence, and maintain oil phase continuity, thereby maintaining oil-water emulsion stability and allowing lubricating oil to remain in a stable emulsion state under high water content, ensuring normal low-temperature cold start. It has good detergency, which helps to suspend and disperse oil sludge, carbon deposits, and wear particles generated during engine operation, preventing them from depositing on high-temperature friction surfaces, keeping the friction pair clean, avoiding local hot spots and abnormal wear, and indirectly protecting the oil film integrity. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1is the result graph after the engine oil thermal stability test of Example 3;

[0048] Figure 2 is the result graph after the engine oil thermal stability test of Comparative Example 1;

[0049] Figure 3 is the result graph after the crankcase simulation test of Example 3;

[0050] Figure 4 is the result graph after the crankcase simulation test of Comparative Example 1;

[0051] Figure 5 is the result graph after the emulsion normal temperature standing for 120h of Example 3;

[0052] Figure 6 is the result graph after the emulsion normal temperature standing for 120h of Comparative Example 2;

[0053] Figure 7 is the 100℃ kinematic viscosity change trend graph;

[0054] Figure 8 is the oxidation value change trend graph;

[0055] Figure 9 is the nitration value change trend graph;

[0056] Figure 10 is the base value change trend graph;

[0057] Figure 11 is the acid value change trend graph;

[0058] Figure 12 is the iron content change trend graph. DETAILED DESCRIPTION

[0059] I. Raw material preparation

[0060] The gas engine oil composition includes, by mass content: antioxidant anti-wear agent: 1%-5%; metal detergent: 1.0%-5.0%; ashless dispersant 1.0%-15%; friction-reducing anti-wear agent: 0.1%-0.5%; viscosity index improver: 5.0%-15.0%; pour point depressing emulsifier: 0.1%-1.5%; and the remainder is Group III base oil.

[0061] The prepared materials are zinc dialkyldithiocarbamate, oligomer synthetic arylamine antioxidant, long-chain alkyl thio hindered phenol, magnesium alkylsalicylate, calcium sulfide alkylphenol, boron polyisobutylene succinimide dispersant 1.0%-10%, molybdate 0.1%-0.5%, ethylene-propylene polymer tackifier 5.0%-15.0%, poly methacrylate pour point depressant emulsifier (specifically VISCOPLEX® 6-850 (4001) of Wincrete Special Chemical (Shanghai) Co., Ltd., commonly known as V6-850) and poly methacrylate pour point depressant, alkylated diphenylamine, and the rest is Ⅲ paraffin-based synthetic oil (consisting of Ⅲ 250N base oil and Ⅲ 150N base oil).

[0062] The pour point depressant emulsifier is V6-850, i.e., the emulsifier product VISCOPLEX® 6-850 (4001) of Wincrete Special Chemical (Shanghai) Co., Ltd. The antioxidant and anti-wear agent is zinc dialkyldithiocarbamate (ZnDDC), oligomer synthetic arylamine antioxidant, and long-chain alkyl thio hindered phenol, and the mass ratio is (0.5-1.0):(1.0-2.0):(1.0-2.0). The metal detergent is magnesium alkylsalicylate and calcium sulfide alkylphenol, and the mass ratio is (0.5-2.0):(0.5-2.0).

[0063] The oligomer synthetic arylamine antioxidant is alkylated N-phenyl-alpha-naphthylamine and alkylated diphenylamine in a polyol ester solvent, and the reaction raw materials are chemically reacted under the condition of a reaction temperature of 155°C by the initiation of an initiator under the protection of inert gas nitrogen. After 8h of reaction, the red-brown viscous oligomer synthetic amine antioxidant is obtained by reduced pressure distillation.

[0064] II. Preparation method

[0065] A preparation method of a long-range gas engine lubricating oil, comprising the following steps:

[0066] 1) Sol: according to the formula proportion, first mix the dry gel form OCP tackifier block with an appropriate amount of base oil, heat to 130°C and stir to dissolve, stand for 7h, and obtain product a;

[0067] 2) Compounding: put product a and the remaining base oil into a blending kettle, and add dispersant, antioxidant and anti-wear agent, detergent, and anti-wear agent according to the formula proportion, start stirring, heat to 60°C and keep, continue stirring for 4h, and obtain product b;

[0068] 3) Blending: finally add the pour point depressant emulsifier to product b, the stirring temperature is 45°C, and continue stirring for 3h.

[0069] The application will be described in further detail below with reference to the drawings and in conjunction with specific embodiments. It should be emphasized that the following description is merely exemplary and is not intended to limit the scope of the application and its applications.

[0070] With reference to the following drawings, non-limiting and non-exclusive embodiments will be described, in which the same reference numerals denote the same parts, unless otherwise specified.

[0071] I. Examples and Comparative Examples

[0072] 1. Example 1

[0073] Raw material preparation: based on the total mass of the diesel engine oil, the composition and content of the raw materials are calculated as follows: zinc dialkyldithiocarbamate 0.5%, oligomer synthetic amine type antioxidant 1%, long-chain alkyl thio hindered phenol 1%, magnesium alkylsalicylate 3%, sulfided alkyl phenol calcium 2%, boronized polyisobutylene succinimide type dispersant 9%, molybdate 0.5%, OCP tackifier 6%, polymethacrylate pour point depressant emulsifier 0.8%, and the rest is Group III paraffin-based synthetic oil.

[0074] Preparation method:

[0075] 1) Sol: first mix the tackifier dry gum block with an appropriate amount of base oil according to the formula ratio, heat to 130°C and stir to dissolve, stand for 7h, to obtain product a;

[0076] 2) Compounding: put product a and the remaining base oil into a blending kettle, add the dispersant, antioxidant and anti-wear agent, detergent, anti-wear and anti-wear agent in the formula ratio in turn, start stirring and heat to 60°C and keep, continue stirring for 4h, to obtain product b;

[0077] 3) Blending: finally add the pour point depressant emulsifier to product b, the stirring temperature is 45°C, and continue stirring for 3h.

[0078] 2. Example 2

[0079] Raw material preparation: based on the total mass of the diesel engine oil, the composition and content of the raw materials are calculated as follows: zinc dialkyldithiocarbamate 0.5%, oligomer synthetic amine type antioxidant 1%, long-chain alkyl thio hindered phenol 1%, magnesium alkylsalicylate 3%, sulfided alkyl phenol calcium 2%, boronized polyisobutylene succinimide type dispersant 9%, molybdate 0.5%, OCP tackifier 6%, polymethacrylate pour point depressant emulsifier 0.8%, and the rest is Group III paraffin-based synthetic oil.

[0080] Preparation method: same as Example 1.

[0081] 3. Example 3

[0082] Raw material preparation: based on the total mass of diesel engine oil, the composition and content of the raw material are calculated as follows: zinc dialkyldithiocarbamate 1%, oligomer synthetic amine antioxidant 2.5%, long-chain alkyl thio hindered phenol 2%, magnesium alkylsalicylate 2%, sulfided alkylphenol calcium 1%, boronized polyisobutylene succinimide dispersant 10%, molybdate 0.5%, OCP tackifier 8%, polymethacrylate pour point depressant emulsifier 0.8%, and type III paraffin-based synthetic oil in the rest.

[0083] Preparation method: same as example 1.

[0084] 4, example 4

[0085] Raw material preparation: based on the total mass of diesel engine oil, the composition and content of the raw material are calculated as follows: zinc dialkyldithiocarbamate 1.5%, oligomer synthetic amine antioxidant 3%, long-chain alkyl thio hindered phenol 3%, magnesium alkylsalicylate 2%, sulfided alkylphenol calcium 1%, boronized polyisobutylene succinimide dispersant 11%, molybdate 0.5%, OCP tackifier 7%, polymethacrylate pour point depressant emulsifier 0.8%, and type III paraffin-based synthetic oil in the rest.

[0086] Preparation method: same as example 1.

[0087] 5, comparative example 1

[0088] Raw material preparation: based on the total mass of diesel engine oil, the composition and content of the raw material are calculated as follows: zinc dialkyldithiocarbamate 1%, long-chain alkyl thio hindered phenol 2%, magnesium alkylsalicylate 2%, sulfided alkylphenol calcium 1%, boronized polyisobutylene succinimide dispersant 9%, molybdate 0.5%, OCP tackifier 8%, polymethacrylate pour point depressant emulsifier 0.8%, type III paraffin-based synthetic oil in the rest, and alkylated diphenylamine 2.5%.

[0089] Preparation method: same as example 1.

[0090] 6, comparative example 2

[0091] Raw material preparation: based on the total mass of diesel engine oil, the composition and content of the raw material are calculated as follows: zinc dialkyldithiocarbamate 1%, oligomer synthetic amine antioxidant 2%, long-chain alkyl thio hindered phenol 2%, magnesium alkylsalicylate 2%, sulfided alkylphenol calcium 1%, boronized polyisobutylene succinimide dispersant 9%, molybdate 0.5%, OCP tackifier 8%, polymethacrylate pour point depressant 0.8%, and type III paraffin-based synthetic oil in the rest.

[0092] Preparation method: same as example 1.

[0093] 7, the difference between example 1 and example 4

[0094] (1) Compared with Example 1, Example 2 reduces the amount of detergent magnesium alkylsalicylate and sulfurized calcium alkylphenate, increases the amount of dispersant boronized polyisobutylene succinimide, and increases the amount of antioxidant and anti-wear agent zinc dialkyldithiocarbamate (ZnDDC), oligomer synthetic amine antioxidant, and long-chain alkyl thio hindered phenol.

[0095] (2) Compared with Example 2, Example 3 increases the amount of oligomer synthetic amine antioxidant.

[0096] (3) Compared with Example 3, Example 4 increases the amount of dispersant boronized polyisobutylene succinimide, and increases the amount of antioxidant and anti-wear agent zinc dialkyldithiocarbamate (ZnDDC), oligomer synthetic amine antioxidant, and long-chain alkyl thio hindered phenol; and reduces the amount of OCP tackifier.

[0097] (4) Compared with Example 3, Comparative Example 1 uses alkyl diphenylamine to replace oligomer synthetic amine antioxidant.

[0098] (5) Compared with Example 3, Comparative Example 2 uses polymethacrylate pour point depressant to replace polymethacrylate pour point depressant emulsifier.

[0099] The composition and content of the raw materials are shown in Table 1.

[0100]

[0101] II. Physical and chemical indicators

[0102] The physical and chemical detection indicators of the examples and comparative examples of the present application are shown in Table 2. As can be seen from the table, each scheme belongs to a low-sulfur, low-phosphorus, and low-ash scheme, which protects the gas engine aftertreatment system. The examples and comparative examples are all designed to be high-alkaline and low-ash schemes, which meet the acid neutralization capacity requirements. Type III paraffin-based synthetic oil is used, and the evaporation loss is very low, which can achieve low oil consumption and save customers; the sulfur, phosphorus, and ash content in Example 1-Example 4 and Comparative Examples 1-2 are very low, indicating that the use of zinc dialkyldithiocarbamate (ZnDDC) and molybdate (MoDTC) can reduce the sulfur and phosphorus elements of the formula.

[0103]

[0104] III. Simulation performance investigation experiment of the oil product

[0105] 1. The simulation performance test of the examples and comparative examples is carried out. The test results are shown in Table 3.

[0106]

[0107] From the results of the simulation performance test in Table 3, the index of Example 3 is the best, and although the amount of anti-oxidant and anti-wear agent in Example 4 is greater than that in Example 3, the raw material combination of the formulation of Example 3 is the best, and the performance of each single agent is well played. The oxidation induction period, rotary oxygen bomb, engine heat stability test and four-ball machine wear scar diameter test of Comparative Example 1 are significantly worse than those of Example 3, indicating that the oligomer synthetic amine antioxidant overcomes the defects of monomers, has a higher thermal decomposition temperature and oxidation stability, and has more outstanding antioxidant performance than conventional antioxidants, which can meet the anti-oxidation performance requirements of oil products under high temperature working conditions of gas engines. The results of the engine oil heat stability test of Example 3 and Comparative Example 1 are shown in Figure 1 、 Figure 2 The results of the crankcase simulation test and the thermal oxidation simulation test of Comparative Example 2 are significantly worse than those of Example 3, indicating that the polymethyl acrylate pour point depressant has good deposit dispersion performance at high temperatures; at the same time, the difference in gum weight between Example 3 and Comparative Example 1 in the crankcase simulation test also further reflects the dispersion advantage of the formulation of Example 3 for engine internal gum deposits. The results of the crankcase simulation test of Example 3 and Comparative Example 1 are shown in Figure 3 、 Figure 4 .

[0108] 2. Emulsion storage test of Examples 1-4 and Comparative Example 2

[0109] Emulsion stability test method: 85g of the lubricating composition prepared in Examples 1-4 and Comparative Example 2, 15g of pure water were added to a beaker and stirred at a speed of 10000r / min±2000r / min for 2min±2s. The emulsion was observed after storage at room temperature for 24h, 120h, at low temperature of-5℃ for 120h and at high temperature of 150℃ for 120h; the analysis results are shown in Table 4, and the emulsion of Example 3 and Comparative Example 2 after standing at room temperature for 120h is shown in Figures 5-6

[0110]

[0111] The difference between Examples 1-4 and Comparative Example 2 is that the formulation is added with V6-850 pour point depressant, while Comparative Example 2 does not add emulsifier. From the test results in Table 3, it can be seen that the emulsion of the oil product of Examples 1-4 is stable, and the oil can be stored at room temperature and high temperature for a long time after the addition of emulsifier, and the oil and water are not separated, which achieves the purpose of water separation of diesel hybrid engine lubricating oil. Comparative Example 2 does not contain emulsifier, and the oil and water are easy to separate.

[0112] III. Bench performance investigation of oil products

[0113] ​The reliability of the oil product was investigated by conducting 100,000 km engine bench cold and hot shock condition tests on Example 3. There were 2 bench tests. Figures 7-12 From the test results, it can be seen that after 1000 h of bench cold and hot shock condition tests, the oil KV100, oxidation value, nitration value, base value, acid value and iron wear and other indicators were all normal, indicating that Example 3 can meet the technical requirements of a 100,000 km oil change period for a gas engine.

[0114] Those skilled in the art will recognize that numerous modifications can be made to the above description, and that the embodiments are meant to be illustrative only. The embodiments are not meant to be limiting in any way.

[0115] While the present application has been described and illustrated herein by reference to preferred embodiments, various changes in the details of the described embodiments can be made by those skilled in the art without departing from the spirit of the application. Furthermore, numerous substitutions and alterations of the herein described embodiments can be made without departing from the scope of the present application. Accordingly, the application is not limited to the specific embodiments described herein, but instead has broad applicability and can be practiced in ways other than as specifically described herein. It is therefore contemplated to cover by the present application all such and similar embodiments falling within the scope of the present application.

[0116] The foregoing is considered as illustrative only of the principles of the application. Numerous modifications and adaptations thereof will be apparent to those skilled in the art without departing from the spirit or scope of the present application. Therefore, the scope of the application is not to be limited to the specific embodiments disclosed but is intended to cover all such modifications which fall within the scope of the present application.

[0117] While the present application has been described and illustrated herein by reference to preferred embodiments, various changes in the details of the described embodiments can be made by those skilled in the art without departing from the spirit of the application. Furthermore, numerous substitutions and alterations of the herein described embodiments can be made without departing from the scope of the present application. Accordingly, the application is not limited to the specific embodiments described herein, but instead has broad applicability and can be practiced in ways other than as specifically described herein. It is therefore contemplated to cover by the present application all such and similar embodiments falling within the scope of the present application.

[0116] While the present application has been described and illustrated herein by reference to preferred embodiments, various changes in the details of the described embodiments can be made by those skilled in the art without departing from the spirit of the application. Furthermore, numerous substitutions and alterations of the herein described embodiments can be made without departing from the scope of the present application. Accordingly, the scope of the application is not to be limited to the specific embodiments disclosed but is intended to cover all such modifications which fall within the scope of the present application.

[0117] While the present application has been described and illustrated herein by reference to preferred embodiments, various changes in the details of the described embodiments can be made by those skilled in the art without departing from the spirit of the application. Furthermore, numerous substitutions and alterations of the herein described embodiments can be made without departing from the scope of the present application. Accordingly, the scope of the application is not to be limited to the specific embodiments disclosed but is intended to cover all such modifications which fall within the scope of the present application.

Claims

1. A long-range gas engine lubricating oil, characterized in that, Based on the total weight of the gas engine oil composition, the gas engine oil composition comprises, by mass content: antioxidant and anti-wear agent: 1%-5%; metal detergent: 1.0%-5.0%; ashless dispersant: 1.0%-15%; friction-reducing and anti-wear agent: 0.1%-0.5%; viscosity index improver: 5.0%-15.0%; pour point depressant emulsifier: 0.1%-1.5%; the remainder being Group III base oil.

2. The long-mileage gas engine lubricating oil according to claim 1, characterized in that, The decoction emulsifier is V6-850, and the antioxidant and anti-wear agent is zinc dialkyl dithiocarbamate, oligomer synthetic aromatic amine antioxidant, and long-chain alkyl thiohedral phenol, with a mass ratio of (0.5-1.0): (1.0-2.0): (1.0-2.0).

3. The long-mileage gas engine lubricating oil according to claim 1, characterized in that, The metal cleaning agent is a mixture of alkyl salicylate magnesium and sulfide alkylphenol calcium in a mass ratio of (0.5-2.0):(0.5-2.0). The ashless dispersant is a boronized polyisobutylene succinimide dispersant. The friction-reducing and wear-resistant agent is molybdate ester. The viscosity index improver is an OCP viscosity index improver.

4. The long-mileage gas engine lubricating oil according to claim 1, characterized in that, The pour point depressant is polymethyl methacrylate, and the base oil is selected from Group III paraffinic synthetic oil.

5. The long-mileage gas engine lubricating oil according to claim 2, characterized in that, The oligomer-synthesized aromatic amine antioxidant is prepared by reacting alkylated N-phenyl-α-naphthylamine and alkylated diphenylamine in a polyol ester solvent under inert nitrogen gas at a reaction temperature of 100℃-190℃. The reactants undergo a chemical reaction initiated by an initiator. After 6-12 hours of reaction, the mixture is distilled under reduced pressure to obtain a reddish-brown viscous oligomer-synthesized amine antioxidant.

6. The long-mileage gas engine lubricating oil according to claim 1, characterized in that, The preferred structural formula of the long-chain alkyl thiohed phenol is shown in Formula I: 。 7. The long-mileage gas engine lubricating oil according to claim 3, characterized in that, The alkyl salicylate magnesium is a specific type of alkyl salicylate, and the structure of the alkyl salicylate is preferably shown in Formula II: ； Where R is an alkyl group containing 10-20 carbon atoms, M is Ca or Mg, and m and n are non-zero positive integers.

8. The long-mileage gas engine lubricating oil according to claim 3, characterized in that, The sulfidated alkylphenol calcium is a specific type of sulfidated alkylphenol salt, and the preferred structure of the sulfidated alkylphenol salt is shown in Formula III: ； In the formula, R2 is an alkyl group containing 10-24 carbon atoms, M is Ca or Mg, and m2, n2, and x are non-zero positive integers.

9. The long-mileage gas engine lubricating oil according to claim 3, characterized in that, The structure of the boronized polyisobutylene succinimide dispersant is shown in Formula IV: ； Wherein, PIB is polyisobutylene, with a molecular weight of 900-1300, and r is a non-zero positive integer; In the formula, R = C n H 2n+1 n = 4 - 12; The decoction-depressant emulsifier is a polymethacrylate with the structure shown in Formula V: ; In the formula, R = C n H 2n+1 , n = 10 - 20.

10. A method for preparing a long-range gas engine lubricating oil as described in any one of claims 1-9, characterized in that, Includes the following steps: 1) Sol: According to the formula ratio, cut the dry gel form of OCP adhesive index agent into pieces and mix with an appropriate amount of base oil. The mass ratio of OCP adhesive index agent to base oil is 1:

10. Heat to 128-138℃, stir and dissolve, and let stand for 6-8 hours to obtain product a. 2) Compounding: Place product a and the remaining base oil into a mixing tank, and add dispersant, antioxidant and anti-wear agent, detergent and friction-reducing and anti-wear agent in sequence according to the formula ratio. Start stirring and heat to 58℃-68℃ and keep warm. Continue stirring for 3-6 hours to obtain product b. 3) Blending: Finally, add the decoction emulsifier to product b, stir at 40℃-50℃ for 3-6 hours.

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