Composite cleaning agent for motor train unit wheel axle

Abstract

The application provides a composite cleaning agent, a preparation method thereof and application of the composite cleaning agent in cleaning a wheel shaft of a motor train unit. The composite cleaning agent comprises the following components in percentage by mass: 2-5% of nitrogen-doped citric acid carbon quantum dots, 10-15% of a non-ionic surfactant, 10-15% of a solvent, 1-2.0% of a composite corrosion inhibitor, 0.5-1% of a chelating agent, 0.5-1% of a penetrating agent and the balance of deionized water. The nitrogen-doped citric acid carbon quantum dots are selected from citric acid-triethanolamine carbon quantum dots and citric acid-ethylenediamine carbon quantum dots. The composite cleaning agent has good stability, is easy to rinse, has strong cleaning power and has extremely low metal corrosion.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of cleaning agents, and particularly relates to a composite cleaning agent for cleaning the wheel shaft of a motor train unit. BACKGROUND

[0002] With more and more high-speed train motor train units put into operation, the cleaning and maintenance tasks of vehicle components are increasing year by year, and the importance is also increasingly prominent. The wheel shaft is a key core component of the motor train unit. During the operation and service of the wheel shaft, the surface will be contaminated with dirt. According to the existing state, the dirt on the surface of the wheel shaft can be divided into two types: solid dirt, such as sand, dust, metal chips, abrasives, metal corrosion products, and inorganic salt precipitates, etc.; liquid dirt, such as grinding fluid, cutting fluid, drawing fluid, hydraulic oil, guide rail oil, grease, polishing paste, acidic and alkaline residues, etc. If the dirt on the surface of the wheel shaft is not cleaned in time, it will cause or accelerate the corrosion or corrosion of the wheel shaft, increase the friction and wear, produce surface defects, shorten the service life, and even affect the driving safety in severe cases. As the main consumable in the wheel shaft cleaning process, the cleaning agent directly determines the cleaning effect of the wheel shaft. However, there is currently no cleaning agent specifically for the wheel shaft of the motor train unit. In addition, under high temperature and high speed with air friction, stubborn stains will form on the surface of the wheel shaft, which is difficult to clean with general cleaning agents. However, the common strong cleaning agents on the market are mostly highly corrosive and not suitable for the wheel shaft of the motor train unit.

[0003] Carbon quantum dots are a new type of nanomaterial with an exciton Bohr radius, which have the advantages of non-toxicity, good biocompatibility, low price, chemical stability, and similar fluorescence characteristics, and have been widely applied in the fields of optoelectronic devices, photocatalysts sensors, and biological images.

[0004] In recent years, the application of carbon quantum dots in cleaning, scale removal, and scale inhibition has also attracted attention. Li Hui synthesized L-CCQDs and Ly-CCQDs carbon quantum dot scale inhibitors by one-pot hot melt polycondensation method using citric acid and L-ascorbic acid as raw materials, respectively (Li Hui. Preparation and performance of carboxyl carbon quantum dot scale inhibitor [D]. Northeast Petroleum University. June 6, 2023). The inventors also previously proposed an invention patent application entitled "Environmentally friendly nano insulator cleaning agent and its preparation method" (Publication No. CN116376642A, Publication Date July 4, 2023). The cleaning agent contains 0.2-0.8% carbon quantum dots, which are prepared by microwave method using ethylenediamine and citric acid as raw materials. SUMMARY

[0005] The present application provides a composite cleaning agent specifically for cleaning the wheel shaft of a motor train unit. The composite cleaning agent is green and environmentally friendly, has strong scale removal ability, and not only does not corrode the wheel shaft metal, but also has corrosion inhibition and corrosion prevention effects.

[0006] Therefore, the present invention adopts the following technical solution:

[0007] A composite cleaning agent, by mass percentage, comprises the following components: 2%-5% nitrogen-doped citric acid carbon quantum dots, 10%-15% nonionic surfactant, 10%-15% solvent, 1%-2.0% composite corrosion inhibitor, 0.5%-1% chelating agent, 0.5%-1% penetrant, and the balance deionized water.

[0008] Preferably, the composite cleaning agent, by mass percentage, comprises the following components: 3%-4% nitrogen-doped citric acid carbon quantum dots, 10%-13% nonionic surfactant, 10%-15% solvent, 1.3%-1.8% composite corrosion inhibitor, 1% chelating agent, 0.5%-1% penetrant, and the balance deionized water.

[0009] Preferably, the nitrogen-doped citrate carbon quantum dots are selected from citrate-triethanolamine carbon quantum dots and citrate-ethylenediamine carbon quantum dots.

[0010] More preferably, the mass ratio of citric acid-triethanolamine carbon quantum dots to citric acid-ethylenediamine carbon quantum dots is 1:1 to 1:2.

[0011] Preferably, the citric acid-triethanolamine carbon quantum dots have a mass ratio of citric acid to triethanolamine of 1:0.6 to 1:1.0; more preferably, it has a mass ratio of 1:0.7 to 1:0.8.

[0012] Preferably, the citric acid-ethylenediamine carbon quantum dots have a mass ratio of citric acid to ethylenediamine of 1:0.2-1:1.0; more preferably, it has a mass ratio of 1:0.3-1:0.5.

[0013] Preferably, the citric acid-triethanolamine carbon quantum dots and the citric acid-ethylenediamine carbon quantum dots are prepared by a microwave method.

[0014] As a preferred embodiment, the present invention provides a method for preparing the citric acid-triethanolamine carbon quantum dots, comprising the following steps:

[0015] (1) Add citric acid and triethanolamine to deionized water in a mass ratio and dissolve them completely so that the total mass percentage concentration of citric acid and triethanolamine is 3%-10%;

[0016] (2) Place the solution obtained in step (1) into a microwave device and react it under microwave heating;

[0017] (3) The reaction system after microwave treatment in step (2) is freeze-dried to obtain solid powder.

[0018] Preferably, in step (1), the total mass percentage concentration of citric acid and triethanolamine in water is 8%-9%.

[0019] Preferably, in step (2), the microwave conditions are: microwave power of 700-900W, temperature inside the microwave device of 190-240℃, and reaction time of 20-30min.

[0020] More preferably, the microwave conditions are: microwave power of 800W, internal temperature of microwave equipment of 210-230℃, and reaction time of 25min.

[0021] As another preferred embodiment, the present invention provides a method for preparing the citric acid-ethylenediamine carbon quantum dots, comprising the following steps:

[0022] (a) Add citric acid and ethylenediamine to deionized water in a mass ratio and dissolve them completely so that the total mass percentage concentration of citric acid and ethylenediamine is 3%-10%;

[0023] (b) Place the solution obtained in step (a) into a microwave device and react it under microwave heating;

[0024] (c) The reaction system after microwave treatment in step (b) is freeze-dried to obtain a solid powder.

[0025] Preferably, in step (a), the total mass percentage concentration of citric acid and ethylenediamine in water is 5%-8%.

[0026] Preferably, in step (b), the microwave conditions are: microwave power of 700-900W, temperature inside the microwave equipment of 200-220℃, and reaction time of 10-15min.

[0027] More preferably, the microwave conditions are: microwave power of 800W, internal temperature of microwave equipment of 205-215℃, and reaction time of 10min.

[0028] Preferably, the nonionic surfactant is selected from at least one of AEO-9, AEO-7 and 6501.

[0029] More preferably, the nonionic surfactant is AEO-9 and 6501 in any mass ratio.

[0030] Most preferably, the nonionic surfactant is AEO-9 and 6501 in a mass ratio of 1:0.5-1:0.8.

[0031] Preferably, the solvent is selected from at least one of N-methylpyrrolidone, diethylene glycol butyl ether, dipropylene glycol methyl ether, and diethylene glycol methyl ether.

[0032] More preferably, the solvent is N-methylpyrrolidone and dipropylene glycol methyl ether in any volume ratio.

[0033] Most preferably, the solvent is N-methylpyrrolidone and dipropylene glycol methyl ether in a mass ratio of 1:0.5-1:1.

[0034] Preferably, the composite corrosion inhibitor is composed of one selected from sodium benzoate, thiourea and benzotriazole, and one selected from VClrus-406T02 steel corrosion inhibitor produced by Suzhou Ruister Protective Packaging Materials Co., Ltd., and RP-890 and RP-895H steel corrosion inhibitor produced by Shenyang Ruichi Surface Technology Co., Ltd.

[0035] More preferably, the composite corrosion inhibitor is composed of sodium benzoate and RP-895H.

[0036] Most preferably, the mass ratio of sodium benzoate to RP-895H is 1:1 to 1:2.5.

[0037] Preferably, the chelating agent is selected from at least one of polyaspartic acid and diethylamine methylglycine.

[0038] More preferably, the chelating agent is polyaspartic acid.

[0039] Most preferably, the chelating agent is polyaspartic acid with a molecular weight of 4000-6000.

[0040] Preferably, the penetrant is sodium dioctyl maleate sulfonate.

[0041] Another objective of this invention is to provide a method for preparing the above-mentioned composite cleaning agent, comprising mixing the components evenly according to the stated proportions.

[0042] Preferably, the preparation method includes mixing the components uniformly in the specified proportions in a mixing device equipped with a stirring device.

[0043] More preferably, the stirring device rotates at a speed of 200-500 rpm and the stirring time is 10-30 min, more preferably 20 min.

[0044] Furthermore, a third objective of this invention is to provide the application of the aforementioned composite cleaning agent in cleaning the wheel axles of high-speed trains, specifically as follows:

[0045] Dilute the composite cleaning agent with water to a mass percentage concentration of 20%-100%, spray or apply it directly to the surface of the train axle to be cleaned, let it stand for 3-5 minutes to react, and then rinse with water.

[0046] The composite cleaning agent of this invention exhibits good stability and is easy to rinse. Performance tests were conducted on the composite cleaning agent according to Q / CR 468-2015 "Cleaning Agent for External Surfaces of High-Speed ​​Trains," and the results show that the composite cleaning agent of this invention has high oil removal power (up to 96% or more) but extremely low corrosiveness to metals. Furthermore, all components of the composite cleaning agent of this invention are environmentally friendly. Detailed Implementation

[0047] The present invention will be described below with reference to specific embodiments. Those skilled in the art will understand that these embodiments are for illustrative purposes only and do not limit the scope of the invention in any way.

[0048] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. Unless otherwise specified, all raw materials and reagents used in the following examples are commercially available products. The purchase details of some raw materials are as follows:

[0049] Steel corrosion inhibitor VClrus-406T02: Produced by Suzhou Ruister Protective Packaging Materials Co., Ltd.

[0050] Steel corrosion inhibitor RP-895H: Manufactured by Shenyang Ruichi Surface Technology Co., Ltd.

[0051] Polyaspartic acid: molecular weight 5000, 10000, produced by Hebei Xietong Environmental Protection Technology Co., Ltd.

[0052] Penetrant: Sodium dioctyl maleate sulfonate, produced by Jinan Aoxing Chemical Co., Ltd.

[0053] Example 1: Preparation of Citric Acid-Triethanolamine Carbon Quantum Dots

[0054] (1) Add 1-3g of citric acid and 0.7-2.4g of triethanolamine to 50-70ml of deionized water and stir until completely dissolved;

[0055] (2) Place the solution obtained in step (1) into a microwave device, set the microwave power to 700-900W, and react for 20-30 minutes at a temperature of 210-230℃ inside the microwave device.

[0056] (3) The reaction system after microwave treatment in step (2) is freeze-dried to obtain solid powder.

[0057] Example 2: Preparation of citric acid-ethylenediamine carbon quantum dots:

[0058] (a) Add 1-3g of citric acid and 0.5-1g of ethylenediamine to 30-50ml of deionized water and dissolve completely;

[0059] (b) Place the solution obtained in step (a) into a microwave device, set the microwave power to 700-900W, and react for 10-15 minutes at a temperature of 200-220℃ inside the microwave device.

[0060] (c) The reaction system after microwave treatment in step (b) is freeze-dried to obtain a solid powder.

[0061] Examples 3-4 A composite cleaning agent

[0062] Prepare each component as shown in Table 1. Citric acid-triethanolamine carbon quantum dots are prepared according to the method in Example 1, and citric acid-diethylamine carbon quantum dots are prepared according to the method in Example 2. First, add deionized water to the stirred tank, and then add AEO-9, 6501, sodium benzoate, RP-895H, polyaspartic acid, sodium dioctyl maleate sulfonate, N-methylpyrrolidone, dipropylene glycol methyl ether, citric acid-triethanolamine carbon quantum dots and citric acid-ethylenediamine carbon quantum dots in sequence to the stirred tank. Stir at 200-500 rpm for 10-30 min to obtain the final product.

[0063] Comparative Examples 1-9: A Composite Cleaning Agent

[0064] Prepare each component as shown in Table 1, wherein citric acid-triethanolamine carbon quantum dots (if any) are prepared according to the method of Example 1, and citric acid-diethylamine carbon quantum dots (if any) are prepared according to the method of Example 2; and the components are prepared according to the same steps and processes as in Examples 3-4.

[0065] Comparative Example 1 did not contain citric acid-triethanolamine carbon quantum dots or citric acid-diethylamine carbon quantum dots.

[0066] Comparative Example 2 only added citric acid-diethylamine carbon quantum dots, without citric acid-triethanolamine carbon quantum dots;

[0067] Comparative Example 3 only added citric acid-triethanolamine carbon quantum dots, without citric acid-diethylamine carbon quantum dots;

[0068] The mass ratio of citric acid-triethanolamine carbon quantum dots to citric acid-diethylamine carbon quantum dots in Comparative Example 4 was 1:0.4.

[0069] The mass ratio of N-methylpyrrolidone to dipropylene glycol methyl ether in Comparative Example 5 was 1:2.5.

[0070] Comparative Example 6 did not contain polyaspartic acid.

[0071] The mass ratio of AEO-9 to 6501 in Comparative Example 7 was 3:1.

[0072] Comparative Example 8 added polyaspartic acid 10000.

[0073] In Comparative Example 9, the mass ratio of sodium benzoate to RP-895H was 1:10.

[0074] Comparative Example 10: A Composite Cleaning Agent

[0075] Prepare each component as shown in Table 1. Citric acid-triethanolamine carbon quantum dots and citric acid-ethylenediamine carbon quantum dots were both prepared using a hydrothermal method. The specific process steps are as follows:

[0076] I. Hydrothermal Preparation of Citric Acid-Triethanolamine

[0077] (1) Add 2g of citric acid and 1.55g of triethanolamine to 40ml of deionized water and dissolve completely.

[0078] (2) Place the solution obtained in step (1) in a hydrothermal reactor, put it in an oven, set the reaction temperature to 220℃, and the time to 8h.

[0079] (3) The reaction system after the hydrothermal reaction in step (2) is freeze-dried to obtain solid powder.

[0080] II. Hydrothermal preparation of citric acid-ethylenediamine carbon quantum dots:

[0081] (a) Add 2g of citric acid and 0.94g of ethylenediamine to 40ml of deionized water and dissolve completely.

[0082] (b) Place the solution obtained in step (a) in a hydrothermal reactor, put it in an oven, set the reaction temperature to 210°C, and the reaction time to 8 hours.

[0083] (c) The reaction system after the hydrothermal reaction in step (c) is freeze-dried to obtain a solid powder.

[0084] The composite cleaning agent of this comparative example was prepared by following the same steps as in Examples 3-4.

[0085] Table 1. Formulation of the composite cleaning agents for Examples 3-4 and Comparative Examples 1-10

[0086]

[0087] Test example:

[0088] The performance of the composite cleaning agents prepared in Examples 3-4 and Comparative Examples 1-10 was determined respectively:

[0089] 1. Metal Corrosion Resistance: Tested according to GB / T 35759 "Metal Cleaning Agents". The specific method is as follows: Dilute each cleaning agent with deionized water to 3% by mass, immerse the precisely weighed ER8 and ER9 steel test pieces in the solution, soak at 80℃ for 2 hours, remove and weigh again, and calculate the weight loss.

[0090] 2. Cleaning power: Tested according to Q / CR 468-2015 "Cleaning agents for the exterior surfaces of high-speed trains". The specific method is as follows: Dilute each cleaning agent with deionized water to 5% by mass; apply the oil stain to the surface of a specific test piece, weigh it, and then immerse it in the 5% cleaning agent solution. Soak and wash it in a washing machine, then weigh it again and calculate the percentage of oil stain removed, which is the cleaning power.

[0091] 3. Impact on paint film: First, measure the pencil hardness of the paint film on the surface of a specific test piece; dilute each cleaning agent with deionized water to 5% by mass; immerse the test piece in a 5% cleaning agent solution at 40℃ for 24 hours, remove the test piece, and measure the pencil hardness of the paint film again to see if there is any change compared with the hardness before immersion.

[0092] The measurement results are shown in Table 2.

[0093] Table 2 Performance test results of the composite cleaning agents of Examples 3-4 and Comparative Examples 1-10

[0094]

[0095] The data in Table 2 shows:

[0096] (1) The composite cleaning agent of the present invention has strong cleaning power, is easy to clean, has little impact on the hardness of the paint film, and has extremely low corrosivity to metals.

[0097] (2) Except for Comparative Example 4, all comparative examples are inferior to the composite cleaning agent of the present invention in terms of cleaning power and / or metal corrosion resistance.

[0098] (3) The cleaning agent of Comparative Example 4 contains more citric acid-triethanolamine carbon quantum dots, so the total content of nitrogen-doped citric acid carbon quantum dots exceeds 5%; however, the performance of the cleaning agent is comparable to that of Examples 3 and 4, indicating that excessive use of nitrogen-doped citric acid carbon quantum dots does not improve the performance of the cleaning agent.

Claims

1. A composite cleaning agent, comprising, by mass percentage: 2%-5% nitrogen-doped citric acid carbon quantum dots, 10-15% nonionic surfactant, 10%-15% solvent, 1%-2.0% composite corrosion inhibitor, 0.5-1% chelating agent, 0.5%-1% penetrant, and the balance being deionized water; in, The nitrogen-doped citrate carbon quantum dots are selected from citrate-triethanolamine carbon quantum dots and citrate-ethylenediamine carbon quantum dots with a mass ratio of 1:1 to 1:2; the citrate-triethanolamine carbon quantum dots, with a mass ratio of citric acid to triethanolamine of 1:0.6 to 1:1.0, are prepared by microwave method; the citrate-ethylenediamine carbon quantum dots, with a mass ratio of citric acid to ethylenediamine of 1:0.2 to 1:1.0, are prepared by microwave method. The nonionic surfactant is AEO-9 and 6501 in a mass ratio of 1:0.5-1:0.8; The solvent is N-methylpyrrolidone and dipropylene glycol methyl ether in a mass ratio of 1:0.5-1:1; The composite corrosion inhibitor is composed of sodium benzoate and RP-895H in a mass ratio of 1:1 to 1:2.5; The chelating agent is polyaspartic acid with a molecular weight of 4000-6000; The penetrant is sodium dioctyl maleate sulfonate.

2. The composite cleaning agent according to claim 1, characterized in that, The composite cleaning agent, by mass percentage, consists of the following components: 3%-4% nitrogen-doped citric acid carbon quantum dots, 10-13% nonionic surfactant, 10%-15% solvent, 1.3%-1.8% composite corrosion inhibitor, 1% chelating agent, 0.5%-1% penetrant, and the balance deionized water.

3. The composite cleaning agent according to claim 1 or 2, characterized in that, The citric acid-triethanolamine carbon quantum dots are prepared by the following process: (1) Add citric acid and triethanolamine to deionized water in the mass ratio and dissolve them completely so that the total mass percentage concentration of citric acid and triethanolamine is 3%-10%; (2) Place the solution obtained in step (1) into a microwave device and react it under microwave heating; (3) The reaction system after microwave treatment in step (2) is freeze-dried to obtain solid powder.

4. The composite cleaning agent according to claim 3, characterized in that, The citric acid-triethanolamine carbon quantum dots have a citric acid to triethanolamine mass ratio of 1:0.7 to 1:0.

8.

5. The composite cleaning agent according to claim 3, characterized in that, In step (1), the total mass percentage concentration of citric acid and triethanolamine in water is 8%-9%.

6. The composite cleaning agent according to claim 3, characterized in that, In step (2), the microwave conditions are: microwave power of 700-900W, temperature inside the microwave equipment of 190-240℃, and reaction time of 20-30min.

7. The composite cleaning agent according to claim 6, characterized in that, The microwave conditions are as follows: microwave power is 800W, the temperature inside the microwave equipment is 210-230℃, and the reaction time is 25min.

8. The composite cleaning agent according to claim 1 or 2, characterized in that, The citric acid-ethylenediamine carbon quantum dots are prepared by the following process: (a) Add citric acid and ethylenediamine to deionized water in the specified mass ratio until completely dissolved, so that the total mass percentage concentration of citric acid and ethylenediamine is 3%-10%; (b) Place the solution obtained in step (a) into a microwave device and react it under microwave heating; (c) The reaction system after microwave treatment in step (b) is freeze-dried to obtain a solid powder.

9. The composite cleaning agent according to claim 8, characterized in that, The citric acid-ethylenediamine carbon quantum dots have a mass ratio of citric acid to ethylenediamine of 1:0.3-1:0.

5.

10. The composite cleaning agent according to claim 8, characterized in that, In step (a), the total mass percentage concentration of citric acid and ethylenediamine in water is 5%-8%.

11. The composite cleaning agent according to claim 8, characterized in that, In step (b), the microwave conditions are: microwave power of 700-900W, temperature inside the microwave equipment of 200-220℃, and reaction time of 10-15min.

12. The composite cleaning agent according to claim 11, characterized in that, The microwave conditions are as follows: microwave power is 800W, the temperature inside the microwave equipment is 205-215℃, and the reaction time is 10min.

13. A method for preparing the composite cleaning agent according to any one of claims 1 to 12, comprising mixing the components uniformly according to the stated proportions.

14. The preparation method according to claim 13, characterized in that, The preparation method includes mixing the components uniformly in the specified proportions in a mixing device equipped with a stirring device.

15. The preparation method according to claim 14, characterized in that, The stirring device rotates at 200-500 rpm and the mixing time is 10-30 min.

16. The preparation method according to claim 15, characterized in that, The mixing time is 20 minutes.

17. The application of the composite cleaning agent according to any one of claims 1 to 12 or the composite cleaning agent prepared by the preparation method according to any one of claims 13 to 16 in cleaning the wheel axles of high-speed trains, specifically as follows: Dilute the composite cleaning agent with water to a mass percentage concentration of 20%-100%, spray or coat it directly onto the surface of the train wheel axle to be cleaned, let it stand for 3-5 minutes to react, and then rinse with water.

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