A detergent for lubricating oil and its preparation method

Abstract

The present invention relates to the chemical industry field, and particularly relates to a detergent for lubricating oil and a preparation method thereof. The raw materials of the detergent for lubricating oil are composed of the following components in parts by weight: 35 - 45 parts of lubricating oil base oil, 15 - 25 parts of compound detergent-dispersant, 2 - 6 parts of detergent, 10 - 20 parts of diluent oil, 3 - 7 parts of copolyamide compound, and 2 - 8 parts of ethylene glycol monobutyl ether; the compound detergent-dispersant is prepared by compounding a modified amide auxiliary agent and a modified thioamide in a mass ratio of 1 - 1.5:1. The copolyamide compound, the modified amide auxiliary agent and the modified thioamide prepared by the present invention have excellent dispersion ability for the components generated during the oxidation of lubricating oil into sludge, solid particles and other pollutants, can particularly disperse the solid particles in the lubricating oil, prevent them from aggregating and precipitating, and at the same time can help maintain the acid-base balance of the lubricating oil, and have a good detergency effect.

Description

Technical Field

[0001] The present invention belongs to the chemical industry field, and particularly relates to a detergent for lubricating oil and a preparation method thereof. Background Art

[0002] Lubricating oil oxidatively degrades to produce organic oxygen-containing compounds such as ketones and aldehydes. These organic oxygen-containing compounds are converted into harmful acids through auto-oxidation, and then unsaturated hydrocarbons are generated, forming polymeric sludge. The detergent can chemically treat the metal surface. By removing the deposits on the metal surface, it can neutralize acidic substances and prevent the deposition of solid particles in a finely dispersed state; the dispersant functions by suspending pollutant substances and insoluble oil segments in the lubricating oil. Therefore, these two components have a great impact on the chemical properties of the entire package and the finished lubricating oil.

[0003] Therefore, there is an urgent need for a detergent for lubricating oil with good detergency to improve the performance of lubricating oil. Summary of the Invention

[0004] The purpose of the present invention is to provide a detergent for lubricating oil and a preparation method thereof, aiming to solve the technical problem of poor performance of lubricating oil detergents in the prior art.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions:

[0006] The technical solutions provided by the present invention are as follows:

[0007] In a first aspect, the present invention provides a detergent for lubricating oil. The detergent for lubricating oil specifically includes the following components by weight:

[0008] 35 - 45 parts of lubricating oil base oil, 15 - 25 parts of compound detergent-dispersant, 2 - 6 parts of detergent, 10 - 20 parts of diluent oil, 3 - 7 parts of copolyamide compound, and 2 - 8 parts of ethylene glycol monobutyl ether.

[0009] Preferably, the diluent oil is 150SN and / or 350N.

[0010] Preferably, the detergent includes at least one of magnesium naphthenate and cerium isooctanoate.

[0011] Preferably, the compound detergent-dispersant is a compound of a modified amide auxiliary and a modified thioamide in a mass ratio of 1 - 1.5:1.

[0012] Preferably, the preparation method of the modified amide auxiliary includes the following steps:

[0013] S1: Add 79 - 160 g of acetyl chloride and 76 - 150 g of ammonium thiocyanate to 500 - 1000 mL of acetone. After stirring for 15 - 25 min, filter, and add 121 - 250 g of tris(hydroxymethyl)aminomethane to the filtrate. Continue to stir for 8 - 12 min to obtain an intermediate product;

[0014] S2: Mix 22.2 - 45 g of the intermediate product, 1.7 - 3.4 g of p-toluenesulfonic acid, and 84.1 - 168 g of linoleic acid, and stir and react at 135 - 145 °C for 12 - 18 h to obtain a modified amide auxiliary.

[0015] The structural formula of the modified amide auxiliary is as follows:

[0016]

[0017] Among them, mass spectrometry analysis was performed on the modified amide auxiliary. HRMS(ESI) m / z: 93.73(100.0%), 994.74(66.3%), 995.74(23.6%), 996.74(5.7%), 995.73(5.0%), 996.73(3.0%), 994.73(1.5%), 997.74(1.4%).

[0018] Preferably, the linoleic acid is linoleic acid with an acid content of ≥50%.

[0019] Preferably, the preparation method of the modified thioamide includes the following steps:

[0020] Add 30 - 60 g of oleoyl chloride and 15 - 30 g of ammonium thiocyanate to 300 - 600 mL of acetone. After stirring for 25 - 35 min, filter, add 16 - 32 g of N,N'-bis(2-aminoethyl)-1,3-propanediamine to the filtrate, continue to stir for 55 - 65 min, evaporate the acetone, and wash with petroleum ether 4 - 6 times to obtain the modified thioamide.

[0021] The structural formula of the modified thioamide is as follows:

[0022]

[0023] Among them, mass spectrometry analysis was performed on the modified thioamide. HRMS(ESI) m / z: 469.38(100.0%), 470.38(29.7%), 471.38(5.3%), 471.39(3.9%), 472.38(1.3%).

[0024] The preparation method of the copolyamide compound includes the following steps:

[0025] P1: Add 10 - 20 g of acrylic acid and 37 - 74 g of stearyl alcohol to 40 - 80 mL of toluene, then add 0.042 - 0.084 g of p - toluenesulfonic acid and 0.028 - 0.056 g of hydroquinone, heat at 75 - 85 °C for 10 - 14 h, remove toluene by rotary evaporation, and then vacuum dry at 45 - 55 °C for 3 - 4 h to obtain stearyl acrylate;

[0026] P2: In a nitrogen atmosphere, add 12 - 24 g of maleic anhydride and 41.7 - 82 g of stearyl acrylate to 40 - 50 mL of toluene, stir for 25 - 35 min, then add 0.24 - 0.48 g of benzoyl peroxide, reflux at 105 - 115 °C for 6 - 7 h, pour the mixture into methanol for precipitation, filter, wash the filter residue with methanol solvent 3 - 5 times, and vacuum dry at 75 - 85 °C for 5 - 6 h to obtain a polymeric compound;

[0027] P3: Add 15 - 30 g of p - aminodiphenylamine and 40 - 82 g of the polymeric compound to 50 - 100 mL of xylene, reflux at 141 - 146 °C for 10 - 14 h, remove xylene by rotary evaporation, and dry at 85 - 95 °C for 7 - 8 h to obtain a copolyamide compound.

[0028] The structural formula of the copolyamide compound is as follows:

[0029]

[0030] In a second aspect, the present invention provides a method for preparing a detergent for lubricating oil, comprising the following steps:

[0031] Add 15 - 25 parts of a composite detergent - dispersant, 2 - 6 parts of a detergent, 3 - 7 parts of the copolyamide compound, and 2 - 8 parts of ethylene glycol monobutyl ether to 35 - 45 parts of a lubricating oil base oil, stir at 200 - 300 rpm at 45 - 55 °C for 12 - 18 min, then add 10 - 20 parts of diluent oil, stir at 200 - 300 rpm at 45 - 55 °C for 20 - 30 min, and cool to room temperature to obtain the detergent for lubricating oil.

[0032] In summary, due to the adoption of the above - mentioned technical solutions, the beneficial effects of the present invention are as follows:

[0033] 1. The copolyamide compound, modified amide additive, and modified thioamide prepared by the present invention have excellent dispersing ability for the components generated during the oxidation of lubricating oil into sludge, solid particles, and other pollutants. They can particularly disperse the solid particles in the lubricating oil, prevent them from aggregating and precipitating, and at the same time can help maintain the acid - base balance of the lubricating oil and cooperate synergistically with the detergent, having good detergency.

[0034] 2. The oleophobic groups of the modified amide additives prepared by the present invention enhance their solubility in lubricating oils. The non-polar hydrophobic tails not only prevent polar soot particles from adhering to the metal surface but also prevent them from aggregating into larger clusters. The hydrophilic polar head segments are attracted to the lubricating oil contaminants and surround the solid contaminants. The modified amide additives and modified thioamides contain more NH groups. The increase in NH groups increases the neutralization power and improves the dispersibility by forming hydrogen bonds with oxidation components such as alcohols, aldehydes, ketones, and acids, and they cooperate synergistically to enhance the effect as lubricating oil dispersants. The polar secondary aniline molecules in the copolymer amide compound structure have cleaning properties, hinder sludge deposition, and have acid neutralization efficiency. The imino groups in the copolymer amide compound, modified amide additives, and modified thioamides can help maintain the acid-base balance of the lubricating oil, prevent acidic substances from having a corrosive effect on the metal surface under high-temperature or high-pressure conditions, extend the service life of the lubricating oil and machine components, and cooperate with detergents to maintain the performance stability and cleanliness of the lubricating oil.

[0035] 3. The copolymer amide compound prepared by the present invention has a diphenylamine group. The longer alkyl chain polymer reduces the absorbance of 2,2-diphenyl-picrylhydrazyl (DPPH) to a greater extent, thus having a greater free radical scavenging ability and being a good antioxidant. Due to the availability of protons, this proton is easily transferred from diphenylamine to the hydrocarbon group, and the hydrocarbon group will further be converted into hydrocarbons to prevent degradation, thereby improving the oxidation stability of the lubricating oil. At the same time, it contains aminobenzene diamine, so it also has good anti-corrosion properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0037] Figure 1 It is a process flow chart of the detergent for lubricating oil of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0039] Example 1

[0040] This embodiment discloses a preparation method of a modified amide auxiliary, comprising the following steps:

[0041] S1: Add 120 g of acetyl chloride and 114 g of ammonium thiocyanate to 750 mL of acetone. After stirring for 20 min, filter, and add 181.5 g of tris(hydroxymethyl)aminomethane to the filtrate. Continue to stir for 10 min to obtain an intermediate product.

[0042] S2: Mix 33.3 g of the intermediate product, 2.6 g of p-toluenesulfonic acid, and 126.2 g of linoleic acid. Stir and react at 140 °C for 15 h to obtain the modified amide auxiliary.

[0043] Example 2

[0044] This embodiment discloses a preparation method of a modified thioamide, comprising the following steps:

[0045] Add 45 g of oleoyl chloride and 22.5 g of ammonium thiocyanate to 450 mL of acetone. After stirring for 30 min, filter, add 24 g of N,N'-bis(2-aminoethyl)-1,3-propanediamine to the filtrate. Continue to stir for 60 min, evaporate the acetone, and wash with petroleum ether 5 times to obtain the modified thioamide.

[0046] Example 3

[0047] This embodiment discloses a preparation method of a copolyamide compound, comprising the following steps:

[0048] P1: Add 15 g of acrylic acid and 55.5 g of stearyl alcohol to 60 mL of toluene, then add 0.063 g of p-toluenesulfonic acid and 0.042 g of hydroquinone. Heat at 80 °C for 12 h, rotary evaporate to remove toluene, and then vacuum dry at 50 °C for 3.5 h to obtain stearyl acrylate.

[0049] P2: In a nitrogen atmosphere, add 18 g of maleic anhydride and 62.6 g of stearyl acrylate to 45 mL of toluene. After stirring for 30 min, add 0.36 g of benzoyl peroxide, and reflux and react at 110 °C for 6.5 h. Pour the mixture into methanol, precipitate, filter, wash the filter residue with methanol solvent 4 times, and vacuum dry at 80 °C for 5.5 h to obtain a polymeric compound.

[0050] P3: Add 22.5 g of p-aminodiphenylamine and 61 g of the polymeric compound to 75 mL of xylene, reflux and react at 143 °C for 12 h, rotary evaporate to remove xylene, and dry at 90 °C for 7.5 h to obtain the copolyamide compound.

[0051] Example 4

[0052] Refer to Figure 1As shown, this embodiment discloses a preparation method of a detergent for lubricating oil, including the following steps:

[0053] Add 22.5 g of a composite detergent-dispersant, 4 g of a detergent, 5 g of the copolyamide compound prepared in Example 3, and 5 g of ethylene glycol monobutyl ether to 40 g of a lubricating oil base stock, stir at 250 rpm for 16 min at 50 °C, then add 15 g of a diluent oil, stir at 250 rpm for 25 min at 50 °C, and cool to room temperature to obtain the detergent for lubricating oil.

[0054] The diluent oil is 150SN.

[0055] The detergent is magnesium naphthenate.

[0056] The composite detergent-dispersant is a compound prepared by blending the modified amide auxiliary agent prepared in Example 1 and the modified thioamide prepared in Example 2 at a mass ratio of 1.3:1.

[0057] Example 5

[0058] Refer to Figure 1 As shown, this embodiment discloses a preparation method of a detergent for lubricating oil, including the following steps:

[0059] Add 15 g of a composite detergent-dispersant, 6 g of a detergent, 3 g of the copolyamide compound prepared in Example 3, and 8 g of ethylene glycol monobutyl ether to 35 g of a lubricating oil base stock, stir at 200 rpm for 18 min at 55 °C, then add 10 g of a diluent oil, stir at 200 rpm for 30 min at 55 °C, and cool to room temperature to obtain the detergent for lubricating oil.

[0060] The diluent oil is 350N.

[0061] The detergent includes at least one of cerium isooctanoate.

[0062] The composite detergent-dispersant is a compound prepared by blending the modified amide auxiliary agent prepared in Example 1 and the modified thioamide prepared in Example 2 at a mass ratio of 1:1.

[0063] Example 6

[0064] Refer to Figure 1 As shown, this embodiment discloses a preparation method of a detergent for lubricating oil, including the following steps:

[0065] Add 25 g of a composite detergent-dispersant, 2 g of a detergent, 7 g of the copolymerized amide compound prepared in Example 3, and 2 g of ethylene glycol monobutyl ether to 45 g of a lubricating oil base stock. Stir at 300 rpm for 12 min at 45°C, then add 20 g of a diluent oil and stir at 300 rpm for 20 min at 45°C. Cool to room temperature to obtain the detergent for lubricating oil.

[0066] The diluent oil is 350N.

[0067] The detergent is magnesium naphthenate.

[0068] The composite detergent-dispersant is a compound prepared by blending the modified amide auxiliary agent prepared in Example 1 and the modified thioamide prepared in Example 2 at a mass ratio of 1.5:1.

[0069] Example 7

[0070] Refer to Figure 1 As shown, this example discloses a preparation method of a detergent for lubricating oil, including the following steps:

[0071] Add 17 g of a composite detergent-dispersant, 5 g of a detergent, 4 g of the copolymerized amide compound prepared in Example 3, and 7 g of ethylene glycol monobutyl ether to 38 g of a lubricating oil base stock. Stir at 220 rpm for 16 min at 52°C, then add 18 g of a diluent oil and stir at 280 rpm for 24 min at 48°C. Cool to room temperature to obtain the detergent for lubricating oil.

[0072] The diluent oil is 150SN.

[0073] The detergent is cerium isooctanoate.

[0074] The composite detergent-dispersant is a compound prepared by blending the modified amide auxiliary agent prepared in Example 1 and the modified thioamide prepared in Example 2 at a mass ratio of 1.1:1.

[0075] Example 8

[0076] Refer to Figure 1 As shown, this example discloses a preparation method of a detergent for lubricating oil, including the following steps:

[0077] Add 23 g of a composite detergent-dispersant, 3 g of a detergent, 6 g of the copolymerized amide compound prepared in Example 3, and 4 g of ethylene glycol monobutyl ether to 42 g of a lubricating oil base stock. Stir at 280 rpm for 14 min at 48°C, then add 12 g of a diluent oil and stir at 220 rpm for 28 min at 52°C. Cool to room temperature to obtain the detergent for lubricating oil.

[0078] The diluent oil is 350N.

[0079] The detergent is cerium isooctanoate.

[0080] The composite detergent-dispersant is prepared by compounding the modified amide auxiliary agent prepared in Example 1 and the modified thioamide prepared in Example 2 at a mass ratio of 1-1.5:1.

[0081] Comparative Example 1

[0082] Compared with Example 4, in the process of preparing the detergent for lubricating oil in Comparative Example 1, the copolymerized amide compound was not added, and other conditions remained unchanged.

[0083] Comparative Example 2

[0084] Compared with Example 4, in the process of preparing the detergent for lubricating oil in Comparative Example 2, the modified thioamide was not added, that is, the composite detergent-dispersant was the modified amide auxiliary agent, and other conditions remained unchanged.

[0085] Comparative Example 3

[0086] Compared with Example 4, in the process of preparing the detergent for lubricating oil in Comparative Example 3, the modified amide auxiliary agent was not added, that is, the composite detergent-dispersant was the modified thioamide, and other conditions remained unchanged.

[0087] Experimental Example

[0088] The performances of the detergents for lubricating oil prepared in Examples 4-8 and Comparative Examples 1-3 were tested. 1.5 parts of the detergent for lubricating oil was added to 100 parts of the lubricating base oil without addition, and the standard federal test method was used to determine the efficiency of sediment particles (engine sludge) suspended in the lubricating oil and the coke deposition (mg); after oxidation for 72 h, the dispersibility was detected; the precipitation of colloidal substances, etc. were based on the SH / T0300-92 crankcase simulation test method (QZX method); the effect test results are shown in Table 1:

[0089] Table 1

[0090]

[0091]

[0092] As can be seen from Table 1, the detergents for lubricating oil prepared in Examples 4-8 can significantly improve the detergency and dispersibility of lubricating oil. From the comparison between Comparative Example 1 and Example 4, it can be known that in the process of preparing the detergent for lubricating oil according to the present invention, adding a copolyamide compound can significantly improve the detergent for lubricating oil. From the comparison between Comparative Example 2 and Example 4, it can be known that in the process of preparing the detergent for lubricating oil according to the present invention, adding a modified thioamide can significantly improve the detergency of lubricating oil. From the comparison between Comparative Example 3 and Example 4, it can be known that in the process of preparing the detergent for lubricating oil according to the present invention, adding a modified amide auxiliary can significantly improve the detergency of lubricating oil.

[0093] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and all should be covered within the protection scope of the present invention.

[0094] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the present invention to only the specific embodiments. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principle and practical application of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. A detergent for lubricating oil, characterized in that, The raw materials of the detergent for lubricating oil are composed of the following components in parts by weight: 35-45 parts of lubricating oil base oil, 15-25 parts of compound detergent-dispersant, 2-6 parts of detergent, 10-20 parts of diluent oil, 3-7 parts of copolyamide compound, 2-8 parts of ethylene glycol monobutyl ether; The compound detergent-dispersant is prepared by compounding a modified amide auxiliary agent and a modified thioamide in a mass ratio of 1-1.5:1; The preparation method of the modified amide auxiliary agent includes the following steps: S1: Add 79-160 g of acetyl chloride and 76-150 g of ammonium thiocyanate to 500-1000 mL of acetone, stir for 15-25 min, filter, add 121-250 g of tris(hydroxymethyl)aminomethane to the filtrate, and continue to stir for 8-12 min to obtain an intermediate product; S2: Mix 22.2-45 g of the intermediate product, 1.7-3.4 g of p-toluenesulfonic acid and 84.1-168 g of linoleic acid, and stir and react at 135-145 °C for 12-18 h to obtain a modified amide auxiliary agent; The preparation method of the modified thioamide includes the following steps: Add 30-60 g of oleoyl chloride and 15-30 g of ammonium thiocyanate to 300-600 mL of acetone, stir for 25-35 min, filter, add 16-32 g of N,N'-bis(2-aminoethyl)-1,3-propanediamine to the filtrate, continue to stir for 55-65 min, evaporate acetone, and wash with petroleum ether 4-6 times to obtain a modified thioamide; The preparation method of the copolyamide compound includes the following steps: P1: Add 10-20 g of acrylic acid and 37-74 g of stearyl alcohol to 40-80 mL of toluene, then add 0.042-0.084 g of p-toluenesulfonic acid and 0.028-0.056 g of hydroquinone, heat at 75-85 °C for 10-14 h, remove toluene by rotary evaporation, and vacuum dry at 45-55 °C for 3-4 h to obtain stearyl acrylate; P2: In a nitrogen atmosphere, add 12-24 g of maleic anhydride and 41.7-82 g of stearyl acrylate to 40-50 mL of toluene, stir for 25-35 min, add 0.24-0.48 g of benzoyl peroxide, reflux and react at 105-115 °C for 6-7 h, pour the mixture into methanol, precipitate, filter, wash the filter residue with methanol solvent 3-5 times, and vacuum dry at 75-85 °C for 5-6 h to obtain a polymer compound; P3: Add 15-30 g of p-phenylenediamine and 40-82 g of the polymer compound to 50-100 mL of xylene, reflux and react at 141-146 °C for 10-14 h, remove xylene by rotary evaporation, and dry at 85-95 °C for 7-8 h to obtain a copolyamide compound.

2. The detergent for lubricating oil according to claim 1, characterized in that, The diluent oil is 150SN and / or 350N.

3. The detergent for lubricating oil according to claim 1, wherein, The detergent includes at least one of magnesium naphthenate and cerium isooctanoate.

4. A method for preparing a detergent for lubricating oil according to any one of claims 1-3, characterized in that, Including the following steps: Add 15 - 25 parts of a composite detergent - dispersant, 2 - 6 parts of a detergent, 3 - 7 parts of a copolyamide compound, and 2 - 8 parts of ethylene glycol monobutyl ether to 35 - 45 parts of a lubricating oil base stock. Stir at 200 - 300 rpm for 12 - 18 min at 45 - 55°C, then add 10 - 20 parts of a diluent oil and stir at 200 - 300 rpm for 20 - 30 min at 45 - 55°C. Cool to room temperature to obtain the detergent for lubricating oil.

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