Chelated lithium molybdenum ion lubricating oil additive, its preparation method and application

Abstract

The present invention discloses a chelated lithium molybdenum ion lubricating oil additive and its preparation method and application. The preparation method includes the following steps: add kaolin and hexadecyltrimethoxysilane to deionized water, react with magnetic stirring and ultrasonic treatment, and then stir; after the reaction, filter, wash and dry the reaction product to obtain alkylated kaolin; then add alkylated kaolin and aminopropyltrimethoxysilane to deionized water, react with magnetic stirring and ultrasonic treatment, and then stir; after the reaction, centrifuge, wash and dry the reaction product to obtain aminated / alkylated kaolin; then add aminated / alkylated kaolin to chelated lithium molybdenum ion solution, react with stirring; after the reaction, filter, wash and dry the reaction product to obtain chelated lithium molybdenum ion lubricating oil additive. The prepared additive has good dispersibility in base oil and has excellent friction reducing and anti-friction ability.

Description

[Technical Field]

[0001] The present invention relates to the technical field of lubricating oils, and more particularly to a chelated lithium molybdenum ion lubricating oil additive and its preparation method and application. [Background technology]

[0002] Lubricants are liquid or semi-solid lubricants used in machinery parts in industries such as aviation, machining, metallurgy, automobiles, transportation, and coal mining to reduce friction and protect machinery and workpieces. Their primary functions include lubrication, cooling aids, rust prevention, cleaning, sealing, and buffering. Lubricants generally consist of two components: base oil and additives. Base oil is the main component of a lubricant and determines its basic properties. Additives compensate for or improve the performance deficiencies of the base oil, thereby imparting new properties to the lubricant. In other words, they are important components of a lubricant, and their type, quality, and addition rate directly affect the lubricant's performance.

[0003] Nano-additives are mainly used in lubrication as friction reducers, anti-wear agents, extreme pressure additives, running-in agents, etc., and have acquired completely new physical and chemical properties due to their special effects (e.g., surface / interface effects, small size effects, dimension effects, etc.). Nano-additives have superior performance that is incomparable to conventional additives or lubricants, and therefore have the potential to replace conventional additives.

[0004] With the increasing emphasis on environmental protection and the continuous development of nanomaterial technology, the development of clean, non-polluting / low-polluting micro- and nano-lubricant additives has become a rapidly growing research topic. Two-dimensional layered materials have a layered structure. That is, atoms within each atomic layer are connected by strong covalent bonds, while adjacent atomic layers are bound by weak van der Waals forces, allowing the layers to slide easily against each other. Therefore, all materials widely used in solid lubrication have a layered structure. Among two-dimensional layered materials, silicate minerals are environmentally friendly and inexpensive. Research has also shown that silicate minerals, such as kaolin, montmorillonite, and serpentine, have certain friction-reducing and anti-friction effects as lubricant additives.

[0005] Patent Document 1 discloses a high-performance water-soluble lubricating oil for racks. The lubricating oil contains, by weight, 80 to 100 parts base oil, 3 to 5 parts hydroxyethyl cellulose, 6 to 8 parts sodium polyacrylate, 8 to 12 parts ethylene glycol, 1 to 2 parts modified graphite powder, 3 to 9 parts polymer blend of nanokaolin and nanoaluminum oxide, 0.3 to 0.5 parts polyvinyl alcohol emulsion, 5 to 15 parts stabilizer, 2 to 10 parts surfactant, 0.2 to 1 part defoamer, and 30 to 70 parts deionized water. The combination of various additives improves the lubricating oil's various performance properties and enhances its stability and lubrication effect. This also effectively prevents damage such as wear and scratches on the rack tooth surface, thereby extending the rack's service life.

[0006] However, due to its solid particle nature, high chemical activity, and ease of adsorption, kaolin has poor dispersion stability in liquid lubricating media and is prone to aggregation and precipitation, which not only prevents it from effectively performing its friction reduction, friction prevention, and self-repairing functions, but also may lead to abrasive wear due to aggregation.

[0007] Ionic liquids possess excellent properties, such as nonvolatility, nonflammability, thermal stability, low melting point, and good electrical conductivity, making them ideal lubricating materials. In 2001, Ye et al. were the first to discover that ionic liquids are multifunctional lubricants with excellent performance. Their detailed and systematic research on ionic liquid lubricants has attracted considerable attention from researchers both in Japan and abroad. To date, ionic liquids have been widely used as base oils, additives, lubricating films, and conductive lubricating greases. However, research has revealed that while typical ionic liquids are soluble in highly polar polyethylene glycols, their solubility in less polar hydrocarbon-based lubricating oils is very low (<<1%). [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Chinese Patent Application Publication No. 107446682A Summary of the Invention [Problem to be solved by the invention]

[0009] In order to overcome the drawbacks of the prior art, the present invention aims to provide a chelated lithium molybdenum ion lubricating oil additive, which has good dispersibility in base oil and excellent friction reducing and anti-friction effects, and its preparation method and application. [Means for solving the problem]

[0010] To achieve the above objectives, the present invention adopts the following technical solutions.

[0011] The method for preparing the chelated lithium molybdenum ion lubricating oil additive includes the following steps:

[0012] (1) Kaolin and hexadecyltrimethoxysilane are added to deionized water, and the mixture is stirred with magnetic stirring and ultrasonic treatment to cause a reaction. After the reaction is complete, the reaction product is filtered, washed, and dried to obtain alkylated kaolin.

[0013] (2) Alkylated kaolin and aminopropyltrimethoxysilane are added to deionized water, and the mixture is stirred with magnetic stirring and ultrasonic treatment to react. After the reaction is complete, the reaction product is centrifuged, washed, and dried to obtain aminated / alkylated kaolin.

[0014] (3) The aminated / alkylated kaolin is added to the chelated lithium molybdenum ion solution and stirred to react. After the reaction is completed, the reaction product is filtered, washed, and dried to obtain the chelated lithium molybdenum ion lubricating oil additive.

[0015] Preferably, in step (1), the mass / volume ratio of kaolin, hexadecyltrimethoxysilane, and deionized water is 1 g:0.05-0.5 g:100 mL.

[0016] Preferably, in step (1), magnetic stirring is performed for 10 to 20 minutes, ultrasonic treatment is performed for 30 to 60 minutes, and the reaction is carried out under reaction conditions of 40 to 60° C. for 2 to 6 hours.

[0017] Preferably, in step (2), the mass / volume ratio of alkylated kaolin, aminopropyltrimethoxysilane, and deionized water is 1 g:0.05-0.2 g:100 mL.

[0018] Preferably, in step (2), the magnetic stirring time is 15 to 30 minutes, the ultrasonic treatment is 10 to 20 minutes, and the reaction is carried out under reaction conditions of 50 to 80° C. for 4 to 10 hours.

[0019] Preferably, in step (3), the chemical formula of the chelated lithium molybdenum ion is Li2C10H16N2O8Mo, and the concentration of the chelated lithium molybdenum ion solution is 0.1 to 1 wt%.

[0020] Preferably, in step (3), the chelated lithium molybdenum ion solution is prepared as follows: EDTA is weighed and dissolved in dilute aqueous ammonia to form an EDTA solution with a concentration of 1 mol / L. Next, lithium acetate and molybdenum nitrate are weighed and added to the EDTA solution in a molar ratio of EDTA:Li:Mo=1:1-2:0.5-1, and the mixture is stirred at 80°C for 2 hours to react, thereby obtaining a chelated lithium molybdenum ion solution.

[0021] Preferably, in step (3), the reaction is carried out under stirring at a temperature of 70 to 90° C. for 6 to 10 hours. The mass / volume ratio of aminated / alkylated kaolin to the chelated lithium molybdenum ion solution is 1 g:30 to 50 mL.

[0022] The present invention further claims protection for lubricating oil additives prepared using said method.

[0023] The present invention further claims protection for the application of said additive in lubricating oil, wherein the concentration of said additive in the lubricating oil is 0.01-0.13 wt%.

[0024] Preferably, the lubricating oil includes Kunlun Tianxin F5000 lubricating oil, SF15W-40 type lubricating oil and Great Wall SJ10W-40 lubricating oil, or mineral base oil, synthetic base oil. [Effects of the Invention]

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1) In the chelated lithium molybdenum ion lubricating oil additive provided by the present invention, the layered structure of kaolin is advantageous in reducing momentum transfer between fluid layers, separating the fluid layers, thereby reducing fluid resistance and lowering oil viscosity. Furthermore, by sequentially modifying kaolin with hexadecyltrimethoxysilane and aminopropyltrimethoxysilane, the dispersibility of kaolin in the oil is improved, allowing more lubricating oil molecules to be transported to the friction surface. Furthermore, a mechanical deposition film is formed in the depressions of the friction surface, providing a filling and repair effect, thereby improving lubrication efficiency.

[0027] 2) In the chelated lithium molybdenum ion lubricating oil additive provided by the present invention, the chelated lithium molybdenum ion is bonded to the surface of aminated / alkylated kaolin, thereby improving the compatibility of the chelated lithium molybdenum ion with the oil phase. During the friction process, the chelated lithium molybdenum ion can undergo complex tribochemical reactions with elements on the surface of the friction pair, forming a boundary lubricating film on the surface of the friction pair. This gives the additive excellent friction reduction and anti-friction capabilities. DETAILED DESCRIPTION OF THE INVENTION

[0028] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be described in more detail below in conjunction with examples. Of course, the specific examples described herein are only for illustrating the present invention, and are not intended to limit the present invention.

[0029] Unless otherwise specified, all chemical reagents and materials in the present invention are commercially available or synthesized from commercially available raw materials.

[0030] Kaolin with a particle size of 0.5 to 2 μm was purchased from Fuhua Nano Materials Co., Ltd.

[0031] Chelated lithium molybdenum ion solution was provided by Yatian Group.

[0032] The present invention will be further described below with reference to specific examples.

[0033] Example 1

[0034] The method for preparing the chelated lithium molybdenum ion lubricating oil additive included the following steps:

[0035] (1) 1 g of kaolin and 0.5 g of hexadecyltrimethoxysilane were added to 100 mL of deionized water, magnetically stirred for 20 minutes, and ultrasonically treated for 60 minutes. The mixture was then stirred at 60°C for 6 hours. After the reaction was complete, the reaction product was filtered, washed, and dried to obtain alkylated kaolin.

[0036] (2) 1 g of alkylated kaolin and 0.2 g of aminopropyltrimethoxysilane were added to 100 mL of deionized water, magnetically stirred for 30 minutes, and ultrasonically treated for 20 minutes. The mixture was then stirred at 80°C for 10 hours. After the reaction was complete, the reaction product was centrifuged, washed, and dried to obtain aminated / alkylated kaolin.

[0037] (3) 1 g of aminated / alkylated kaolin was added to 50 mL of a 1 wt% lithium molybdenum ion chelate solution and reacted for 10 hours with stirring at 90°C. After the reaction was completed, the reaction product was filtered, washed, and dried to obtain a lithium molybdenum ion chelate lubricating oil additive.

[0038] The prepared additive was added to SF15W-40 type lubricating oil at a concentration of 0.13 wt%.

[0039] Example 2

[0040] The method for preparing the chelated lithium molybdenum ion lubricating oil additive included the following steps:

[0041] (1) 1 g of kaolin and 0.05 g of hexadecyltrimethoxysilane were added to 100 mL of deionized water, magnetically stirred for 10 minutes, and ultrasonically treated for 30 minutes. The mixture was then stirred at 40°C for 2 hours. After the reaction was complete, the reaction product was filtered, washed, and dried to obtain alkylated kaolin.

[0042] (2) 1 g of alkylated kaolin and 0.05 g of aminopropyltrimethoxysilane were added to 100 mL of deionized water, magnetically stirred for 15 minutes, and ultrasonically treated for 10 minutes. The mixture was then stirred at 50°C for 4 hours. After the reaction was complete, the reaction product was centrifuged, washed, and dried to obtain aminated / alkylated kaolin.

[0043] (3) 1 g of aminated / alkylated kaolin was added to 30 mL of 0.1 wt% chelated lithium molybdenum ion solution and reacted for 6 hours with stirring at 70 °C. After the reaction was completed, the reaction product was filtered, washed, and dried to obtain a chelated lithium molybdenum ion lubricating oil additive.

[0044] The prepared additive was added to SF15W-40 type lubricating oil at a concentration of 0.01 wt%.

[0045] Example 3

[0046] The method for preparing the chelated lithium molybdenum ion lubricating oil additive included the following steps:

[0047] (1) 1 g of kaolin and 0.2 g of hexadecyltrimethoxysilane were added to 100 mL of deionized water, magnetically stirred for 15 minutes, and ultrasonically treated for 40 minutes. The mixture was then stirred at 50°C for 3 hours. After the reaction was complete, the reaction product was filtered, washed, and dried to obtain alkylated kaolin.

[0048] (2) 1 g of alkylated kaolin and 0.1 g of aminopropyltrimethoxysilane were added to 100 mL of deionized water, magnetically stirred for 20 minutes, and ultrasonically treated for 15 minutes. The mixture was then stirred at 60°C for 6 hours. After the reaction was complete, the reaction product was centrifuged, washed, and dried to obtain aminated / alkylated kaolin.

[0049] (3) 1 g of aminated / alkylated kaolin was added to 40 mL of a 0.6 wt% chelated lithium molybdenum ion solution and stirred at 80°C for 8 hours. After the reaction was completed, the reaction product was filtered, washed, and dried to obtain a chelated lithium molybdenum ion lubricating oil additive.

[0050] The prepared additive was added to SF15W-40 type lubricating oil at a concentration of 0.05 wt%.

[0051] Example 4

[0052] The method for preparing the chelated lithium molybdenum ion lubricating oil additive included the following steps:

[0053] (1) 1 g of kaolin and 0.3 g of hexadecyltrimethoxysilane were added to 100 mL of deionized water, magnetically stirred for 18 minutes, and ultrasonically treated for 50 minutes. The mixture was then stirred at 55°C for 5 hours. After the reaction was complete, the reaction product was filtered, washed, and dried to obtain alkylated kaolin.

[0054] (2) 1 g of alkylated kaolin and 0.15 g of aminopropyltrimethoxysilane were added to 100 mL of deionized water, magnetically stirred for 25 minutes, and ultrasonically treated for 15 minutes. The mixture was then stirred at 70°C for 8 hours. After the reaction was complete, the reaction product was centrifuged, washed, and dried to obtain aminated / alkylated kaolin.

[0055] (3) 1 g of aminated / alkylated kaolin was added to 45 mL of 0.8 wt% chelated lithium molybdenum ion solution and reacted for 9 hours with stirring at 80°C. After the reaction was completed, the reaction product was filtered, washed, and dried to obtain a chelated lithium molybdenum ion lubricating oil additive.

[0056] The prepared additive was added to SF15W-40 type lubricating oil at a concentration of 0.1 wt%.

[0057] Comparative Example 1

[0058] The method for preparing the lubricating oil additive included the following steps:

[0059] (1) 1 g of kaolin and 0.2 g of aminopropyltrimethoxysilane were added to 100 mL of deionized water, magnetically stirred for 30 minutes, and ultrasonically treated for 20 minutes. The mixture was then stirred at 80°C for 10 hours. After the reaction was complete, the reaction product was centrifuged, washed, and dried to obtain aminated kaolin.

[0060] (2) 1 g of aminated kaolin was added to 50 mL of a 1 wt% chelated lithium molybdenum ion solution, and the mixture was stirred at 90°C for 10 hours to react. After the reaction was completed, the reaction product was filtered, washed, and dried to obtain the additive.

[0061] The prepared additive was added to SF15W-40 type lubricating oil at a concentration of 0.13 wt%.

[0062] Comparative Example 2

[0063] The method for preparing the lubricating oil additive included the following steps:

[0064] (1) 1 g of kaolin and 0.5 g of hexadecyltrimethoxysilane were added to 100 mL of deionized water, magnetically stirred for 20 minutes, and ultrasonically treated for 60 minutes. The mixture was then stirred at 60°C for 6 hours. After the reaction was complete, the reaction product was filtered, washed, and dried to obtain alkylated kaolin.

[0065] (2) 1 g of alkylated kaolin was added to 50 mL of a 1 wt% chelated lithium molybdenum ion solution, and the mixture was stirred at 90°C for 10 hours to react. After the reaction was completed, the reaction product was filtered, washed, and dried to obtain the additive.

[0066] The prepared additive was added to SF15W-40 type lubricating oil at a concentration of 0.13 wt%.

[0067] Comparative Example 3

[0068] The method for preparing the lubricating oil additive included the following steps:

[0069] (1) 1 g of kaolin and 0.5 g of hexadecyltrimethoxysilane were added to 100 mL of deionized water, magnetically stirred for 20 minutes, and ultrasonically treated for 60 minutes. The mixture was then stirred at 60°C for 6 hours. After the reaction was complete, the reaction product was filtered, washed, and dried to obtain alkylated kaolin.

[0070] (2) 1 g of alkylated kaolin and 0.2 g of aminopropyltrimethoxysilane were added to 100 mL of deionized water, magnetically stirred for 30 minutes, and ultrasonically treated for 20 minutes. The mixture was then stirred at 80°C for 10 hours. After the reaction was complete, the reaction product was centrifuged, washed, and dried to obtain aminated / alkylated kaolin.

[0071] The prepared aminated / alkylated kaolin was added to SF15W-40 type lubricating oil at a concentration of 0.13 wt%.

[0072] The anti-friction and friction-reducing properties of the lubricating oils prepared in Examples 1 to 4 and Comparative Examples 1 to 3 were investigated using an SGW-10A four-ball friction and wear tester. High-quality chromium alloy bearing steel GCr15 was used for the experimental steel balls. The Rockwell hardness HRC was 64 to 66, and the diameter was 12.7 mm. The load during the experiment was 147 N, the rotation speed was 1200 r / min, and the time was 60 min. After the experiment, the steel balls were thoroughly cleaned, and the size of the friction scars on the steel balls after the friction experiment was observed using an optical microscope. Furthermore, the mass loss of the steel balls before and after the experiment was measured using a 0.1 mg electronic balance. The measurement results are shown in Table 1.

[0073] [Table 1]

[0074] The above description is merely a preferred specific embodiment of the present invention, and the scope of protection of the present invention is not limited thereto. Within the technical scope disclosed in the present invention, any equivalent replacement or modification made by a person skilled in the art based on the technical solutions and inventive ideas of the present invention shall be covered in the scope of protection of the present invention.

Claims

1. 1. A method for preparing a chelated lithium molybdenum ion lubricating oil additive, comprising: (1) adding kaolin and hexadecyltrimethoxysilane to deionized water, and then carrying out magnetic stirring and ultrasonic treatment, followed by stirring to react; after the reaction is completed, filtering, washing, and drying the reaction product to obtain alkylated kaolin; (2) adding alkylated kaolin and aminopropyltrimethoxysilane to deionized water, and then carrying out magnetic stirring and ultrasonic treatment, followed by stirring to react; after the reaction is completed, the reaction product is centrifuged, washed, and dried to obtain aminated / alkylated kaolin; (3) adding the aminated / alkylated kaolin to the chelated lithium molybdenum ion solution, stirring to react, and after the reaction is completed, filtering, washing, and drying the reaction product to obtain the chelated lithium molybdenum ion lubricating oil additive.

2. 2. The method according to claim 1, wherein in step (1), the mass-volume ratio of kaolin, hexadecyltrimethoxysilane, and deionized water is 1 g:0.05-0.5 g:100 mL.

3. 2. The method according to claim 1, wherein in step (1), the magnetic stirring is performed for 10-20 min, the ultrasonic treatment is performed for 30-60 min, and the reaction is performed under the reaction conditions of 40-60°C for 2-6 h.

4. 2. The method of claim 1, wherein in step (2), the mass / volume ratio of alkylated kaolin, aminopropyltrimethoxysilane, and deionized water is 1 g:0.05-0.2 g:100 mL.

5. The method according to claim 1, wherein in step (2), the magnetic stirring time is 15-30 min, the ultrasonic treatment is 10-20 min, and the reaction condition is 50-80°C, and the reaction is carried out for 4-10 h.

6. 2. The method of claim 1, wherein in step (3), the chemical formula of the lithium molybdenum ion chelate is Li2C10H16N2O8Mo, and the concentration of the lithium molybdenum ion chelate solution is 0.1-1 wt%.

7. 2. The method according to claim 1, wherein in step (3), the reaction conditions are 70-90°C, stirring and reacting for 6-10 hours, and the mass / volume ratio of aminated / alkylated kaolin to chelated lithium molybdenum ion solution is 1 g:30-50 mL.

8. A lubricating oil additive prepared using the method of any one of claims 1 to 7.

9. 9. Use of the additive of claim 8 in a lubricating oil, comprising: The use characterized in that the concentration of the additive in the lubricating oil is 0.01 to 0.13 wt %.

10. 9. Use of the additive of claim 8 in a lubricating oil, comprising: The lubricating oil is selected from Kunlun Tianxin F5000 lubricating oil, SF15W-40 type lubricating oil, and Great Wall SJ10W-40 lubricating oil, or mineral base oil, synthetic base oil.

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