Metal anti-corrosion and anti-freezing solution and preparation method thereof

Abstract

The technical scheme of the invention discloses a metal anti-corrosion and anti-freezing solution and a preparation method thereof. The metal anti-corrosion and anti-freezing solution comprises the following raw materials in parts by weight: 20-40 parts of sodium formate, 5-10 parts of glycerol, 3-6 parts of polyoxyethylene 40 hydrogenated castor oil (PEG-40), 2-5 parts of sodium laurate, 8-16 parts of hexadecyl trimethyl ammonium bromide, 10-15 parts of chloromethyl palmitate, 4-10 parts of a pH regulator and 60-90 parts of ultrapure water. Through cooperation of sodium formate, glycerin, PEG-40, sodium laurate, cetyltrimethylammonium bromide, chloromethyl hexadecanoate and the like, the freezing point of the anti-freezing solution is effectively reduced, and the anti-freezing solution is not liable to volatilize, is suitable for open scenes such as an open heat source tower system and the like, and effectively improves the corrosion resistance of metal.

Description

Technical Field

[0001] The present invention relates to the technical field of antifreeze, and particularly relates to a metal anti-corrosion antifreeze and a preparation method thereof. Background Art

[0002] The heat source tower heat pump system is a set of energy-saving and environmentally friendly green central air-conditioning solution composed of a heat source tower heat pump host, a heat source tower, a special antifreeze (used in winter), a solution automatic detection and adding device, and a remote control device. When cooling in summer, the heat source tower is used as a cooling tower to discharge indoor heat into the air through a fan. When heating in winter, the heat source tower uses antifreeze with a lower freezing point to absorb sensible heat and latent heat in the air, without frosting or defrosting, ensuring a continuous and stable heat source for users. The heat source tower heat pump system has great advantages in efficient cooling and heating, and central heating in the north. The pipelines of the heat source tower heat pump system are mainly made of metal, and metals are prone to corrosion in various environments and conditions, such as oxidation, sulfidation, hydrogenation, etc. These corrosions not only affect the appearance and performance of metals, but may also lead to the damage of equipment or structures. In cold regions, liquids often operate below 0°C and are prone to freezing, which can cause the equipment or system to malfunction. The special antifreeze for the heat source tower heat pump system can not only lower the freezing point of the liquid to prevent freezing, but also exchange heat with the air during winter operation to absorb energy in the air. However, traditional antifreezes often have a corrosive effect on metals, affecting the normal operation of the system. Therefore, it is necessary to develop an antifreeze that can both prevent freezing and prevent the corrosion of metal pipelines.

[0003] Patent CN 105255456 A discloses an antifreeze with metal anti-corrosion performance and a preparation method thereof. The raw materials include ethylene glycol, polyethylene glycol, sodium hydroxide, sodium phosphate, sodium nitrate, sodium silicate, methacrylic acid, dodecyl trimethyl ammonium chloride, 2-methylthio benzothiazole, a pH regulator, a dye, sodium stearyl fumarate, and distilled water. It has a low freezing point, a small foam volume, a short defoaming time, and good corrosion resistance. However, since it mainly relies on ethylene glycol to achieve antifreeze, ethylene glycol-based antifreeze has weak volatility, and using it in an open system (such as an open heat source tower system) will cause ethylene glycol to gradually volatilize and lose its antifreeze effect. Patent CN 102040955 B discloses an inhibitory ethylene glycol antifreeze, and the raw materials include glycol compounds, potassium salts, azole compounds, and water-soluble dyes, which can effectively prevent freezing and inhibit bacteria. However, due to the presence of potassium salts, it has a certain corrosive effect on some metals, and the anti-corrosion performance still needs to be improved. Therefore, it is necessary to develop an antifreeze with a low freezing point, strong corrosion resistance, low volatility, and low price. Summary of the Invention

[0004] To solve the existing technical problems, the present invention provides a metal anti-corrosion antifreeze and a preparation method thereof. Through the cooperation of sodium formate, glycerol, PEG-40, sodium laurate, cetyltrimethylammonium bromide, chloromethyl cetylate, etc., it not only effectively reduces the freezing point of the antifreeze but also is not easily volatile, is suitable for use in open scenarios such as open heat source tower systems, etc., and effectively improves the metal anti-corrosion performance.

[0005] The technical solution of the present invention is: a metal anti-corrosion antifreeze, comprising the following raw materials in parts by weight: 20 - 40 parts of sodium formate, 5 - 10 parts of glycerol, 3 - 6 parts of polyoxyethylene 40 hydrogenated castor oil (PEG-40), 2 - 5 parts of sodium laurate, 8 - 16 parts of cetyltrimethylammonium bromide, 10 - 15 parts of chloromethyl cetylate, 4 - 10 parts of pH regulator, and 60 - 90 parts of ultrapure water.

[0006] In this formula, sodium formate has the effect of reducing the freezing point of the antifreeze and plays a major antifreeze role. Although sodium formate corrodes metals severely, in the present invention, the corrosion is reduced through the cooperation of sodium formate with other raw materials in the formula, achieving good anti-corrosion performance. Glycerol is used to increase the viscosity of the antifreeze, help reduce evaporation, and at the same time improve the lubricity of the liquid. Controlling the proportion of glycerol within a suitable range helps to maintain the appropriate viscosity and lubrication performance of the antifreeze, while avoiding excessive viscosity caused by too high a proportion and affecting fluidity. PEG-40 helps to increase the stability and lubricity of the antifreeze. Appropriate addition can improve the dispersibility of the liquid, enabling it to maintain good performance at different temperatures. Sodium laurate, as a surfactant, can help the antifreeze disperse and stabilize better. In addition, it also has an anti-corrosion effect and can play a role in protecting metal components in the antifreeze. Cetyltrimethylammonium bromide can improve the lubricity, dispersibility, and anti-foaming performance of the liquid. By adding a limited amount to the antifreeze, it can provide a good lubrication effect, reduce the friction of parts in the system, and extend the service life of the equipment. Chloromethyl cetylate can form a hydrophobic layer on the metal surface, reducing the penetration of water and oxygen, thereby reducing the corrosion risk. The pH regulator is used to control the pH value of the antifreeze. Controlling the pH value is crucial for the stability of the antifreeze, especially to avoid metal corrosion caused by the liquid being too acidic or too alkaline. The proportion of ultrapure water is relatively large, which is used to dilute other components and ensure the uniformity of the liquid, guaranteeing the fluidity and wide temperature adaptability of the antifreeze.

[0007] Preferably, the mass ratio of the sodium formate to the total mass of the sodium formate and the ultrapure water is w, and the lowest application temperature of the metal anti-corrosion antifreeze is T. T and w have a negative correlation.

[0008] Preferably, the lowest application temperature T of the metal anti-corrosion antifreeze is T = -86.47w + 2.2532.

[0009] Preferably, when the minimum application temperature of the metal anti-corrosion antifreeze is -15°C, it comprises the following raw materials by weight: 20 parts of sodium formate, 10 parts of glycerol, 4 parts of polyoxyethylene 40 hydrogenated castor oil (PEG-40), 2 parts of sodium laurate, 10 parts of cetyltrimethylammonium bromide, 10 parts of chloromethyl hexadecanoate, 8 parts of pH regulator, and 80 parts of ultrapure water.

[0010] Preferably, when the minimum application temperature of the metal anti-corrosion antifreeze is -10°C, it comprises the following raw materials by weight: 15 parts of sodium formate, 6 parts of glycerol, 6 parts of polyoxyethylene 40 hydrogenated castor oil (PEG-40), 4 parts of sodium laurate, 13 parts of cetyltrimethylammonium bromide, 10 parts of chloromethyl hexadecanoate, 5 parts of pH regulator, and 85 parts of ultrapure water.

[0011] Preferably, the pH regulator comprises sodium citrate and citric acid in a mass ratio of 1:3.

[0012] A preparation method of a metal anti-corrosion antifreeze comprises the following steps: S1. Put sodium formate and ultrapure water into a beaker and mix them. Put a magnetic stir bar into the beaker and place the beaker on a magnetic stirrer to stir until the sodium formate and ultrapure water are evenly mixed. S2. Add glycerol, polyoxyethylene 40 hydrogenated castor oil (PEG-40), and sodium laurate to the beaker and stir evenly. S3. Add cetyltrimethylammonium bromide and chloromethyl hexadecanoate to the beaker and stir evenly. S4. Add the pH regulator to the beaker and stir evenly to obtain the antifreeze.

[0013] Preferably, the size of the magnetic stir bar is 16mm * 35mm.

[0014] Preferably, the rotation speed of the stirrer in S1 - S4 is 800 - 1000 r / min, the stirring time in S1 is 15 - 20 min, the stirring time in S2 is 20 - 25 min, the stirring time in S3 is 5 - 7 min, and the stirring time in S4 is 5 min.

[0015] By adopting the above technical solutions, the beneficial effects achieved by the present invention are as follows: (1) Through the cooperation of sodium formate, glycerol, PEG-40, sodium laurate, cetyltrimethylammonium bromide, chloromethyl hexadecanoate, etc., the present invention not only effectively reduces the freezing point of the antifreeze but also is not easily volatile, is suitable for use in open scenarios such as open heat source tower systems, etc., and effectively improves the metal anti-corrosion performance.

[0016] (2) The preparation method is simple, the raw materials are easy to obtain, and the cost is low.

[0017] (3)The antifreeze prepared by the present invention is formulated with appropriate component ratios, so that the antifreeze remains stable for a long time within different temperature ranges and avoids premature degradation. Description of the Drawings

[0018] Figure 1 Results after 96h of corrosion characteristic tests on cast iron for Example 1, Comparative Example 1 and Comparative Example 2; Figure 2 Results after 96h of corrosion characteristic tests on copper for Example 1, Comparative Example 1 and Comparative Example 2; Figure 3 Results after 96h of corrosion characteristic tests on galvanized steel sheet for Example 1, Comparative Example 1 and Comparative Example 2; Figure 4 Results of freezing point tests on the antifreeze for Example 1, Example 2 and Comparative Example 3; Figure 5 Freezing point fitting curve of the mass ratio w of sodium formate to the total mass of sodium formate and ultrapure water. Detailed Description of the Invention

[0019] The present invention will be further described in detail below with reference to specific examples. Example 1

[0020] A metal corrosion - resistant antifreeze, comprising raw materials with the following weights: 20g of sodium formate, 10g of glycerol, 4g of polyoxyethylene 40 hydrogenated castor oil (PEG - 40), 2g of sodium laurate, 10g of cetyltrimethylammonium bromide, 10g of cetyl chloroformate, 8g of pH regulator and 80g of ultrapure water.

[0021] The pH regulator is 2g of sodium citrate and 6g of citric acid.

[0022] The preparation method of the above - mentioned metal corrosion - resistant antifreeze comprises the following steps: S1. Put sodium formate and ultrapure water into a beaker and mix them. Put a magnetic stir bar into the beaker and place the beaker on a magnetic stirrer for stirring until sodium formate and ultrapure water are evenly mixed; the size of the magnetic stir bar is 16mm * 35mm, the rotation speed of the stirrer is 800r / min, and the stirring time is 15min; S2. Add glycerol, polyoxyethylene 40 hydrogenated castor oil (PEG - 40) and sodium laurate to the beaker and stir evenly, with a stirring time of 20min; S3. Add cetyltrimethylammonium bromide and cetyl chloroformate to the beaker and stir evenly, with a stirring time of 5min; S4. Add the pH regulator to the beaker and stir evenly, with a stirring time of 5min, then the antifreeze can be obtained. Example 2

[0023] A metal anti-corrosion antifreeze, comprising raw materials with the following weights: 15 g of sodium formate, 6 g of glycerol, 6 g of polyoxyethylene 40 hydrogenated castor oil (PEG-40), 4 g of sodium laurate, 13 g of cetyltrimethylammonium bromide, 10 g of methyl chlorohexadecanoate, 5 g of pH regulator, and 85 g of ultrapure water.

[0024] The pH regulator is 1.25 g of sodium citrate and 3.75 g of citric acid.

[0025] The preparation method of the above metal anti-corrosion antifreeze comprises the following steps: S1. Put sodium formate and ultrapure water into a beaker and mix them. Put a magnetic stir bar into the beaker and place the beaker on a magnetic stirrer to stir, so that sodium formate and ultrapure water are evenly mixed; the size of the magnetic stir bar is 16 mm * 35 mm, the rotation speed of the stirrer is 1000 r / min, and the stirring time is 20 min; S2. Add glycerol, polyoxyethylene 40 hydrogenated castor oil (PEG-40), and sodium laurate to the beaker, and stir evenly, with a stirring time of 25 min; S3. Add cetyltrimethylammonium bromide and methyl chlorohexadecanoate to the beaker, and stir evenly, with a stirring time of 7 min; S4. Add the pH regulator to the beaker, and stir evenly, with a stirring time of 5 min, then the antifreeze can be obtained. Example 3

[0026] A metal anti-corrosion antifreeze, comprising raw materials with the following weights: 20 g of sodium formate, 5 g of glycerol, 6 g of polyoxyethylene 40 hydrogenated castor oil (PEG-40), 4 g of sodium laurate, 10 g of cetyltrimethylammonium bromide, 10 g of methyl chlorohexadecanoate, 5 g of pH regulator, and 90 g of ultrapure water.

[0027] The pH regulator is 1.25 g of sodium citrate and 3.75 g of citric acid.

[0028] The preparation method of the above metal anti-corrosion antifreeze is the same as that of Example 1. Example 4

[0029] A metal anti-corrosion antifreeze, comprising raw materials with the following weights: 20 g of sodium formate, 10 g of glycerol, 6 g of polyoxyethylene 40 hydrogenated castor oil (PEG-40), 5 g of sodium laurate, 16 g of cetyltrimethylammonium bromide, 15 g of methyl chlorohexadecanoate, 8 g of pH regulator, and 80 g of ultrapure water.

[0030] The pH regulator is 2 g of sodium citrate and 6 g of citric acid.

[0031] The preparation method of the above metal anti-corrosion antifreeze is the same as that of Example 1. Example 5

[0032] A metal anti-corrosion antifreeze, comprising raw materials in the following weights: 40 g of sodium formate, 10 g of glycerol, 6 g of polyoxyethylene 40 hydrogenated castor oil (PEG-40), 5 g of sodium laurate, 16 g of cetyltrimethylammonium bromide, 15 g of chloromethyl hexadecanoate, 10 g of pH regulator, and 90 g of ultrapure water.

[0033] The pH regulator is 2.5 g of sodium citrate and 7.5 g of citric acid.

[0034] The preparation method of the above metal anti-corrosion antifreeze is the same as that of Example 1. Example 6

[0035] A metal anti-corrosion antifreeze, comprising raw materials in the following weights: 20 g of sodium formate, 5 g of glycerol, 3 g of polyoxyethylene 40 hydrogenated castor oil (PEG-40), 2 g of sodium laurate, 8 g of cetyltrimethylammonium bromide, 10 g of chloromethyl hexadecanoate, 4 g of pH regulator, and 60 g of ultrapure water.

[0036] The pH regulator is 1 g of sodium citrate and 3 g of citric acid.

[0037] The preparation method of the above metal anti-corrosion antifreeze is the same as that of Example 1. Comparative Example 1

[0038] Ultra-pure water was used as the blank control group Comparative Example 2

[0039] The antifreeze comprises raw materials in the following weights: 20 g of sodium formate, 80 g of ultrapure water, 2 g of sodium citrate, and 6 g of citric acid.

[0040] The preparation method of the antifreeze comprises the following steps: S1. Put sodium formate and ultrapure water into a beaker and mix them. Put a magnetic stirrer bar into the beaker and place the beaker on a magnetic stirrer for stirring to make the sodium formate and ultrapure water evenly mixed; the size of the magnetic stirrer bar is 16 mm * 35 mm, the rotation speed of the stirrer is 800 r / min, and the stirring time is 15 min; S2. Add sodium citrate and citric acid to the beaker and stir evenly. The stirring time is 5 min to obtain the antifreeze. Comparative Example 3

[0041] A metal anti-corrosion antifreeze, comprising raw materials in the following weights: 10 g of sodium formate, 5 g of glycerol, 6 g of polyoxyethylene 40 hydrogenated castor oil (PEG-40), 4 g of sodium laurate, 10 g of cetyltrimethylammonium bromide, 10 g of chloromethyl hexadecanoate, 5 g of pH regulator, and 90 g of ultrapure water.

[0042] The pH regulator is 1.25 g of sodium citrate and 3.75 g of citric acid.

[0043] The preparation method of the above metal anti-corrosion antifreeze is the same as that of Example 1. Corrosion test of antifreeze

[0044] Cast iron sheets, copper sheets, and galvanized steel plates were placed in the liquids prepared in Examples 1-4 and Comparative Examples 1-2 for testing the metal corrosion rate at room temperature (the testing method is a prior art), and the test results are shown in Table 1 and Figures 1-3 as follows.

[0045] Table 1 Metal corrosion rates of Examples 1-4 and Comparative Examples 1-2 From Table 1 and Figure 1 it can be seen that the formate aqueous solution in Comparative Example 2 has the highest corrosion rate for cast iron, while Example 1 has the lowest corrosion rate for cast iron. Compared with Comparative Example 1, the anti-corrosion performance of Example 1 for cast iron is improved by 48%. The antifreeze of Example 1 significantly improves the anti-corrosion property of cast iron.

[0046] From Table 1 and Figure 2 it can be seen that the formate aqueous solution in Comparative Example 2 has the highest corrosion rate for copper, while Example 1 has the lowest corrosion rate for copper. Compared with Comparative Example 1, the anti-corrosion performance of Example 1 for copper is improved by 41%. The antifreeze of Example 1 significantly improves the anti-corrosion property of copper.

[0047] From Table 1 and Figure 3 it can be seen that the formate aqueous solution in Comparative Example 2 has the highest corrosion rate for galvanized steel plate, and pitting corrosion has occurred, while Example 1 has the lowest corrosion rate for galvanized steel plate, and there is still a protective film on the surface of the galvanized steel plate. The antifreeze of Example 1 significantly improves the anti-corrosion property of galvanized steel plate.

[0048] Based on the above experimental results, it can be seen that Example 1 can be used as the antifreeze for the heat source tower heat pump system, effectively improving the metal anti-corrosion property of the heat source tower heat pump system. Freezing point test of antifreeze

[0049] The freezing point tests of Example 1, Example 2, and Comparative Example 3 were carried out on the antifreeze. The freezing point test of the antifreeze mainly uses a freezing point detector. The samples of Example 1, Example 2, and Comparative Example 3 were first loaded into test tubes, and then the test tubes were placed in the constant temperature bath of the freezing point detector. The constant temperature bath uses cooling media such as water or air to cool the test tubes. When the temperature of the sample in the test tube drops to the freezing point, the sample begins to freeze, and at the same time, the test tube wall also begins to release the latent heat of crystallization. At this time, the thermometer of the freezing point detector can sense the temperature change in the constant temperature bath and record the freezing point temperature of the sample. The freezing point test results of Example 1, Example 2, and Comparative Example 3 are as Figure 4 follows.

[0050] In Example 1, the mass ratio w of sodium formate to the total mass of sodium formate and ultrapure water is w = 20 / (20 + 80) = 20%. In Example 2, the mass ratio w of sodium formate to the total mass of sodium formate and ultrapure water is w = 15 / (15 + 85) = 15%. In Comparative Example 3, the mass ratio w of sodium formate to the total mass of sodium formate and ultrapure water is w = 10 / (10 + 90) = 10%. From Figure 4 it can be seen that for Example 1, w is 20%, the freezing point of the antifreeze is -15.183 °C, and the actual minimum application temperature of the antifreeze is specified as -15 °C; for Example 2, w is 15%, the freezing point of the antifreeze is -10.433 °C, and the actual minimum application temperature of the antifreeze is specified as -10 °C; for Comparative Example 3, w is 10%, the freezing point of the antifreeze is -6.536 °C, and the actual minimum application temperature of the antifreeze is specified as -6 °C. Fitting the w and the antifreeze freezing point data, the fitting results are shown in Figure 5 , the freezing point has a linear relationship with w. The freezing point of the antifreeze is also the minimum application temperature T of the antifreeze, T == -86.47w + 2.2532. It can be seen that the higher the value of w, the lower the freezing point of the antifreeze, and the lower the minimum application temperature T of the antifreeze.

Claims

1. A metal anti-corrosion antifreeze liquid, characterized in that: The invention comprises the following raw materials in parts by weight: 20-40 parts of sodium formate, 5-10 parts of glycerol, 3-6 parts of polyoxyethylene 40 hydrogenated castor oil, 2-5 parts of sodium laurate, 8-16 parts of cetyltrimethylammonium bromide, 10-15 parts of chloromethyl hexadecanoate, 4-10 parts of pH regulator and 60-90 parts of ultrapure water.

2. The metal anti-corrosion antifreeze liquid according to claim 1, characterized in that: The mass ratio of the sodium formate to the total mass of the sodium formate and the ultrapure water is w, the minimum application temperature of the metal anti-corrosion antifreeze liquid is T, and T is negatively correlated with w.

3. The metal anti-corrosion antifreeze liquid according to claim 2, characterized in that: The minimum application temperature of the metal anti-corrosion antifreeze liquid is T=-86.47w+2.2532.

4. The metal anti-corrosion antifreeze liquid according to claim 1, characterized in that: When the minimum application temperature of the metal corrosion protection antifreeze liquid is -15°C, the liquid comprises the following raw materials in parts by weight: 20 parts of sodium formate, 10 parts of glycerol, 4 parts of polyoxyethylene 40 hydrogenated castor oil (PEG-40), 2 parts of sodium laurate, 10 parts of cetyltrimethylammonium bromide, 10 parts of cetyl chloromethyl ester, 8 parts of a pH regulator and 80 parts of ultrapure water.

5. The metal anti-corrosion antifreeze liquid according to claim 1, characterized in that: When the minimum application temperature of the metal corrosion protection antifreeze is -10°C, the metal corrosion protection antifreeze comprises the following raw materials in parts by weight: 15 parts of sodium formate, 6 parts of glycerol, 6 parts of polyoxyethylene 40 hydrogenated castor oil (PEG-40), 4 parts of sodium laurate, 13 parts of hexadecyltrimethylammonium bromide, 10 parts of hexadecanoic acid chloromethyl ester, 5 parts of pH regulator and 85 parts of ultrapure water.

6. The metal anti-corrosion antifreeze liquid according to claim 1, characterized in that: The pH adjuster includes sodium citrate and citric acid in a mass ratio of 1:

3.

7. The method for preparing a metal anti-corrosion antifreeze liquid according to claim 1, characterized in that: The following steps are involved: S1. Put sodium formate and ultrapure water into a beaker and mix them. Put a magnet into the beaker and place the beaker on a magnetic stirrer to stir the beaker so that the sodium formate and ultrapure water are evenly mixed. S2. Add glycerin, polyoxyethylene 40 hydrogenated castor oil (PEG-40) and sodium laurate into a beaker and stir evenly; S3, add hexadecyltrimethylammonium bromide and hexadecanoic acid chloromethyl ester into the beaker and stir evenly; S4. Add pH adjuster into the beaker and stir evenly to obtain antifreeze solution.

8. The method for preparing a metal anti-corrosion antifreeze liquid according to claim 7, characterized in that: The size of the magnet is 16mm*35mm.

9. The method for preparing a metal anti-corrosion antifreeze liquid according to claim 7, characterized in that: The agitator speed in S1-S4 is 800-1000 r / min, the stirring time in S1 is 15-20 min, the stirring time in S2 is 20-25 min, the stirring time in S3 is 5-7 min, and the stirring time in S4 is 5 min.

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