Polyacrylate anti-deposition-cerium chloride synergistic composite corrosion inhibitor cooling liquid

Abstract

The invention discloses polyacrylate anti-deposition and cerium chloride synergistic composite corrosion inhibitor cooling liquid, relates to the field of cooling liquid, and is particularly suitable for a multi-metal cooling system. According to the method, polyacrylate, cerium chloride, benzotriazole, benzimidazole, ethylene glycol, deionized water and triethanolamine serve as core raw materials, during preparation, equipment and the raw materials are pretreated, then a base solution is prepared, the pH value is adjusted to be alkalescent, then polyacrylate and cerium chloride are dissolved and coordinated, an auxiliary corrosion inhibitor is added, and synergistic protection is formed. And defoaming, filtering and filling. The cooling liquid adapts to multi-metal material protection through the synergistic effect of deposition resistance of polyacrylate and corrosion inhibition and synergism of cerium chloride, the cooling liquid is diluted according to working conditions during application, waste cooling liquid is discharged after being subjected to combined treatment of biological contact oxidation and Fenton oxidation, a finished product needs to be stored in a proper environment in a sealed mode, and the protection performance, the environmental protection property and the storage stability are effectively considered.

Description

Technical Field

[0001] This invention relates to the field of coolants, and more particularly to a polyacrylate anti-deposition-cerium chloride synergistic composite corrosion inhibitor coolant. Background Technology

[0002] Ethylene glycol-based coolants, due to their excellent thermal conductivity and wide temperature range adaptability, are widely used in industrial heat exchange equipment and automotive cooling systems. To meet equipment protection requirements, existing coolants typically contain functional components such as corrosion inhibitors, scale inhibitors, and defoamers. Corrosion inhibitors often employ single or compound systems of benzotriazole and benzimidazole, while scale prevention often relies on phosphonate compounds. Some formulations introduce rare earth salts to enhance corrosion inhibition. In terms of preparation processes, existing technologies mostly use simple mixing and stirring to add components, performing only basic pretreatment on some key raw materials, lacking systematic design for controlling the reaction system environment, the order of component addition, and dispersion methods. Furthermore, to adapt to the protection requirements of different metal materials, some solutions require the addition of specific corrosion inhibitors for carbon steel, copper alloys, and aluminum alloys, or limit the applicable scenarios of the coolant.

[0003] However, existing technologies still have many problems that urgently need to be solved: First, the corrosion inhibition and anti-deposition functions are disconnected, and the action mechanisms of scale inhibitors and corrosion inhibitors lack synergy. Multiple reagents are often needed to achieve scale inhibition and corrosion inhibition effects separately, which not only increases the complexity and cost of the formulation but may also lead to functional attenuation due to interactions between components. Second, the preparation process logic is not reasonable enough, lacking precise pre-adjustment of the pH value of the reaction system, and the order of addition of core functional components is chaotic. Furthermore, components prone to agglomeration, such as rare earth salts, are not effectively dispersed, resulting in insufficient dissolution and uneven dispersion, affecting the functional stability and long-term effectiveness of the coolant. Third, environmental friendliness and storage stability are difficult to balance. Traditional phosphine-containing scale inhibitors easily cause water pollution, and some rare earth salt components are easily oxidized during storage, producing impurities and causing coolant stratification, discoloration, and other failure phenomena. Fourth, the metal protection compatibility is poor. A single corrosion inhibitor system usually only has a protective effect on specific metal materials. For cooling systems composed of multiple metals, additional special corrosion inhibitors or equipment modifications are required, limiting the application range of the coolant. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this invention is to provide a polyacrylate anti-deposition-cerium chloride synergistic composite corrosion inhibitor coolant to solve one or more problems in the prior art.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows: A polyacrylate anti-deposition-cerium chloride synergistic composite corrosion inhibitor coolant comprises the following components in parts by weight: 8-15 parts polyacrylate, 2-4 parts cerium chloride, 0.8-1.5 parts benzotriazole, 1-3 parts benzimidazole, 480-550 parts ethylene glycol, 280-350 parts deionized water, and 8-12 parts triethanolamine. The polyacrylate has a molecular weight of 8000-50000 and a carboxyl content of 8.5 mmol / g-9.5 mmol / g. The cerium chloride is at least one of anhydrous cerium chloride or cerium chloride heptahydrate.

[0006] Its preparation process includes the following steps: (1) Raw material pretreatment: Ethylene glycol and deionized water were filtered through a precision filter with a filtration pressure of 0.1 MPa to 0.2 MPa. Polyacrylate was dried at 40℃ to 45℃ and a vacuum of -0.08 MPa to -0.09 MPa for 2 to 3 hours.

[0007] (2) Preparation of base liquid: Add pretreated ethylene glycol and deionized water to the stirred tank and stir and mix at a speed of 200r / min~250r / min for 12min~18min.

[0008] (3) pH pre-adjustment: Add triethanolamine to the base solution to adjust the pH of the system to 8.0~8.5, and continue stirring for 5 min.

[0009] (4) Addition of core components: Heat the base liquid to 60℃~70℃, add polyacrylate at a speed of 350r / min~450r / min at an addition rate of 5g / min~10g / min, and stir for 25min~35min. After the system temperature drops to 35℃~45℃, add cerium chloride and turn on the ultrasonic disperser. Disperse ultrasonically at a power of 200W~500W for 13min~17min, and then stir at a speed of 200r / min~300r / min for 20min~25min.

[0010] (5) Addition of auxiliary corrosion inhibitor: Adjust the stirring speed to 150r / min~250r / min, add benzotriazole and benzimidazole in sequence. The addition rate of benzotriazole is 1g / min~2g / min, and the addition rate of benzimidazole is 2g / min~3g / min. Continue stirring for 15min~20min.

[0011] (6) Finished product post-processing: The system is filtered and then filled. The filtration pressure is 0.1MPa~0.2MPa, the filtration speed is 10L / min~15L / min, and the filling flow rate is ≤20L / min.

[0012] Furthermore, the polyacrylate is a polyacrylic acid-hydroxypropyl acrylate copolymer, the copolymer molar ratio of acrylic acid to hydroxypropyl acrylate is 6:4~7:3, and the moisture content of the copolymer is ≤0.5%.

[0013] Furthermore, the anhydrous cerium chloride has a purity ≥99.5%, a metal impurity content ≤0.005%, a particle size of 100-200 mesh, and a water solubility ≥50g / 100mL at 20℃. The cerium chloride heptahydrate has a purity ≥99%, no obvious agglomeration, and a water solubility ≥50g / 100mL at 20℃.

[0014] Furthermore, it also includes 0.3 to 0.8 parts by weight of citric acid as a pH adjuster, with a purity ≥99.0%, a water solubility ≥50g / 100mL at 20℃, and a pH of 2.0 to 2.5 for a 10% aqueous solution. In step (3), if the pH of the system is >8.5, add 10% citric acid solution to finely adjust it to 8.0 to 8.5.

[0015] Furthermore, it also includes 0.2 to 0.5 parts by weight of an organosilicon defoamer, wherein the effective component of the organosilicon defoamer is ≥30% by weight, the defoaming time of a 10% aqueous solution is ≤30s, and it does not contain inorganic ions. After step (5), a defoaming operation is also included: add the organosilicon defoamer, stir at a speed of 100r / min to 200r / min for 5min, let stand for 5min to 8min, retest the pH of the system and maintain it at 8.0 to 8.8.

[0016] Furthermore, in step (1), the mixing vessel and storage tank need to be rinsed with deionized water 3 times before use. After each rinse, they should be soaked for 10 minutes and then dried at 60°C and vacuum degree -0.08MPa for 30 minutes or purged with nitrogen gas at a flow rate of 5L / min for 20 minutes to ensure that the residual moisture on the inner wall of the equipment is ≤0.1%.

[0017] Furthermore, in step (4), the opening and weighing of anhydrous cerium chloride are carried out under nitrogen protection throughout the process. If cerium chloride heptahydrate clumps, it needs to be ground to a particle size ≤200 mesh before use. All pretreated raw materials should be used within 2 hours. The ultrasonic dispersion frequency of cerium chloride is 20kHz~40kHz.

[0018] Furthermore, in step (2), the refractive index of the base solution after mixing is 1.3650~1.3750 at 20℃, and the refractive index deviation of samples taken from different locations is ≤0.002. In step (4), the turbidity of the system after polyacrylate dissolution is ≤5 NTU, and the Ce2+ concentration after cerium chloride dispersion is detected by ICP-OES. 3+ The concentration is 98%~102% of the theoretical addition amount. In step (6), filtration is carried out using a 5μm polypropylene filter cloth, and 1μm precision filter is used for filtration of ethylene glycol and deionized water.

[0019] Furthermore, the application dilution ratio of the coolant is as follows (by volume): 1:1 for coolant to deionized water at -40℃, 1:2 for coolant at -20℃ to 20℃, and 1:3 for coolant at 5℃ to 80℃. The waste coolant after replacement must undergo combined biological contact oxidation and Fenton oxidation treatment before discharge. The residence time for biological contact oxidation is 8-10 hours. In Fenton oxidation, Fe... 2+ The molar ratio of H2O2 to H2O2 is 1:4~8, and the reaction time is 60~90 min.

[0020] Furthermore, the coolant should be stored at a temperature of 5-30°C in a cool, dry, and well-ventilated environment, sealed and protected from light. The unopened shelf life is 12 months, and once opened, it should be used within 3 months.

[0021] Compared with the prior art, the beneficial technical effects of the present invention are as follows: (i) By combining the anti-deposition mechanism of polyacrylate with the corrosion inhibition and enhancement mechanism of cerium chloride, and further supplementing the corrosion inhibition effect of benzotriazole and benzimidazole, an integrated synergistic system of "adsorption-protection-complementarity" is formed. This system is different from the existing technology where corrosion inhibition and anti-deposition functions are separated and the protection of a single corrosion inhibitor is insufficient. It achieves long-term synergy between corrosion inhibition and anti-deposition, which not only avoids the damage of scale deposition to the corrosion inhibition film, but also enhances the protective effect of metal surface through the synergistic effect of rare earth elements. It can meet the dual core requirements without the need to add multiple functional reagents.

[0022] (ii) By combining pH pre-adjustment process with stepwise addition of core components and ultrasonic dispersion process of cerium chloride, a stable weakly alkaline reaction environment is first constructed, then the polyacrylate is fully dissolved and cerium chloride is uniformly dispersed, and finally the auxiliary corrosion inhibitor is efficiently integrated. This is different from the defects of existing technologies such as chaotic process logic, easy agglomeration of components or insufficient dissolution. It ensures that each component plays a synergistic role, improves the functional stability of coolant under wide temperature range and multi-pressure conditions, and can be adapted to different cooling system scenarios without complicated pretreatment.

[0023] (III) By replacing traditional phosphonate antiscaling components with phosphorus-free polyacrylate, and replacing rare earth components such as cerium nitrate (anhydrous or heptahydrate) with cerium chloride (anhydrous or heptahydrate), and adding organosilicon defoamers with no inorganic ion residues, an environmentally friendly composite system is formed. This system is different from the environmental emission failure and easy discoloration caused by the presence of phosphine and nitrate in existing technologies. It achieves a balance between environmental protection and storage stability. The discharged water can meet national standards after conventional treatment, and there is no stratification, discoloration or other failure phenomena during long-term storage.

[0024] (iv) By combining the copper alloy-specific protection mechanism of benzotriazole, the synergistic corrosion inhibition mechanism of benzimidazole, and the broad-spectrum corrosion inhibition mechanism of cerium chloride, the protection needs of multiple metal materials such as carbon steel, copper alloy, and aluminum alloy are covered. Unlike the limitations of existing technologies where a single corrosion inhibitor is only suitable for specific metals and requires the addition of special reagents for different materials, this technology achieves integrated protection of multiple metals. It can directly replace traditional coolant without modifying the cooling system, thus broadening the compatibility of application scenarios. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the process logic for the coolant preparation method in this invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and exemplary descriptions. It should be understood that the structures, proportions, sizes, etc., illustrated in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and are not intended to limit the implementation of this invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives achieved by this invention, should still fall within the scope of the technical content disclosed in this invention.

[0027] Application Overview This invention relates to a polyacrylate anti-deposition-cerium chloride synergistic composite corrosion inhibitor coolant, aiming to solve the problems of poor synergy between corrosion inhibition and anti-deposition in existing coolants, insufficient functional stability, poor environmental protection, and limited multi-metal compatibility. Its core distinguishing features compared to existing technologies are as follows: This invention combines the anti-deposition mechanism of polyacrylate with the corrosion-inhibiting and synergistic mechanism of cerium chloride, along with the auxiliary corrosion-inhibiting effects of benzotriazole and benzimidazole, to form an integrated synergistic system of "adsorption-protection-complementarity." This overcomes the bottlenecks of existing technologies where corrosion inhibition and anti-deposition functions are separated, and single-reagent protection is insufficient. It addresses both core requirements without the need for additional multifunctional reagents. In terms of process design, it innovatively employs a combination of pH pre-adjustment, step-by-step addition of core components, and ultrasonic dispersion of cerium chloride. This first establishes a stable reaction environment, then ensures the full dissolution and uniform dispersion of each component. This approach differs from existing technologies, which suffer from chaotic process logic and easy component aggregation, ensuring the system's functional stability under a wide range of operating conditions. Regarding environmental protection and stability, it replaces traditional phosphonates with phosphorus-free polyacrylate and rare earth components prone to oxidation with cerium chloride. Combined with auxiliary reagents free of inorganic ion residues, it avoids the problems of non-compliance with phosphorus emissions and easy discoloration during storage found in existing technologies, achieving a balance between environmental friendliness and storage stability. Meanwhile, by combining specialized corrosion inhibitors with broad-spectrum corrosion inhibitors, it covers the protection needs of multiple metals such as carbon steel, copper alloys, and aluminum alloys, eliminating the need to add special reagents for different materials. This solves the problem of limited application scenarios of existing technologies and can be directly adapted to various cooling systems.

[0028] Comprehensive explanation

[0029] This invention discloses a polyacrylate anti-deposition-cerium chloride synergistic composite corrosion inhibitor coolant and its preparation method. The invention is fully described below with detailed technical details to ensure that those skilled in the art can completely replicate the technical solution based on the following content.

[0030] Raw material and specification requirements All raw materials used in this invention meet industrial grade or analytical grade standards. The specific specifications and mass fractions of each component are as follows: Polyacrylate: 8 to 15 parts by weight, molecular weight range of 8,000 to 50,000, carboxyl content of 8.5 mmol / g to 9.5 mmol / g, and moisture content of ≤0.5%; polyacrylic acid-hydroxypropyl acrylate copolymer can be selected, with a copolymer molar ratio of acrylic acid to hydroxypropyl acrylate of 6:4 to 7:3. This copolymer enhances the adhesion to the metal surface through hydroxypropyl groups, thereby improving the anti-deposition durability.

[0031] Cerium chloride: 2 to 4 parts by mass, anhydrous cerium chloride or cerium chloride heptahydrate can be selected. Among them, anhydrous cerium chloride has a purity ≥99.5%, a metal impurity content ≤0.005%, a particle size of 100-200 mesh, and a water solubility ≥50g / 100mL at 20℃; cerium chloride heptahydrate has a purity ≥99%, no obvious agglomeration, and a water solubility ≥50g / 100mL at 20℃. Both forms can achieve corrosion inhibition and enhancement by forming a dense oxide film on the metal surface through rare earth ions.

[0032] Benzotriazole: 0.8 to 1.5 parts by weight, purity ≥99.0%, white crystalline powder, melting point 98 to 100℃, ethanol solubility (20℃) ≥20g / 100mL, specially designed for the protection of copper alloy surfaces, forming a chelating film through adsorption.

[0033] Benzimidazole: 1 to 3 parts by weight, purity ≥98.0%, water solubility ≥5g / 100mL at 20℃, melting point 170~174℃, no metal impurities remaining, can work synergistically with cerium chloride to enhance the overall corrosion inhibition effect.

[0034] Ethylene glycol: 480-550 parts by mass, industrial grade purity ≥99.5%, moisture ≤0.1%, color ≤10 Hazen, freezing point ≤-13℃, density (20℃) 1.113~1.115 g / cm³ 3 It serves as a base fluid, providing antifreeze and heat conduction functions.

[0035] Deionized water: 280-350 parts by mass, conductivity ≤5μS / cm at 25℃, pH 6.5-7.5, total dissolved solids ≤10mg / L, free of visible impurities, providing a clean dissolution environment for all components.

[0036] Triethanolamine: 8-12 parts by weight, industrial grade purity ≥99.0%, 10% aqueous solution pH 9.0-11.5, color ≤50 Hazen, density (20℃) 1.124-1.126 g / cm³ 3 It is used to adjust the pH of the system and assist in corrosion inhibition.

[0037] Citric acid: 0.3 to 0.8 parts by weight, industrial grade purity ≥99.0%, water solubility ≥50g / 100mL at 20℃, 10% aqueous solution pH 2.0 to 2.5, used as a pH adjuster to fine-tune excessively high pH in systems.

[0038] Organosilicon defoamer: 0.2 to 0.5 parts by weight, with an effective ingredient content of ≥30%, a defoaming time of ≤30 seconds in a 10% aqueous solution, free of inorganic ions, which can quickly eliminate bubbles generated during the preparation process without affecting the core function of the system.

[0039] Equipment preparation The following equipment is required to implement this invention. All equipment must undergo a cleaning and drying process before use to ensure that no impurities remain: 1. 304 stainless steel storage tank (with stirring device and nitrogen protection interface), 304 stainless steel stirring vessel with heating jacket (speed adjustable from 0 to 500 r / min, equipped with temperature sensor with accuracy ±0.5℃ and nitrogen protection device). 2. 1μm precision filter (made of polypropylene), 5μm polypropylene filter cloth; 3. Ultrasonic disperser (power 200~500W, frequency 20~40kHz), used for the dispersion treatment of cerium chloride; 4. Refractometer, digital pH meter with an accuracy of ±0.01 g (calibrated before use), and electronic balance with an accuracy of ±0.01 g; 5. Turbidity meter with an accuracy of ±0.1 NTU, particulate counter for detecting particles with a diameter ≥1 μm, and inductively coupled plasma optical emission spectrometer (ICP-OES). 6. Vacuum drying oven (for drying after equipment cleaning), inert gas cylinder (nitrogen) with a purity ≥99.9%; 7. Sealed and moisture-proof storage containers (for storing cerium chloride heptahydrate) and grinding equipment (for treating cerium chloride agglomerates).

[0040] Equipment pretreatment process 1. Equipment cleaning: Rinse the mixing vessel, storage tank and connecting pipelines three times with deionized water, soaking for 10 minutes after each rinse, and thoroughly drain the rinsing water to remove residual impurities from the inner wall. 2. Equipment drying: Connect the cleaned equipment to a vacuum drying oven and dry it for 30 minutes at a vacuum of -0.08 MPa and 60°C; or purge with nitrogen for 20 minutes (flow rate 5 L / min) to ensure that there are no visible water droplets on the inner wall of the equipment and that the residual moisture is ≤0.1% to avoid moisture interfering with the stability of the system.

[0041] Preparation process steps (a) Raw material pretreatment Raw material pretreatment must be carried out in an operating environment with a temperature of 20~25℃, relative humidity ≤65%, and ISO Class 8 cleanliness. 1. Ethylene glycol and deionized water are filtered separately through a 1μm precision filter, with the filtration pressure controlled at 0.1MPa~0.2MPa and the filtration speed at 5~10L / min, to remove solid impurities with a particle size ≥1μm; 2. Place polyacrylate (or polyacrylate-hydroxypropyl acrylate copolymer) in a vacuum oven and dry it for 2-3 hours at 40℃~45℃ and a vacuum of -0.08MPa~-0.09MPa. After cooling to room temperature, seal and store for later use, ensuring that the moisture content is ≤0.5%. 3. Cerium chloride pretreatment: Anhydrous cerium chloride must be opened and weighed under nitrogen protection throughout the process to avoid moisture absorption; Cerium chloride heptahydrate is stored in a sealed moisture-proof container. Before adding the material, check whether there is clumping. If there is clumping, it needs to be ground to a particle size ≤200 mesh using a grinding equipment. 4. All pretreated raw materials must be used within 2 hours to avoid secondary moisture absorption or contamination.

[0042] (II) Preparation of base liquid Add pretreated ethylene glycol and deionized water to a nitrogen-protected stirred tank. Adjust the stirring speed to 200-250 rpm and continue stirring for 12-18 minutes. After mixing, use a refractometer to measure the refractive index of the base liquid at 20°C. The refractive index should be 1.3650-1.3750, and the deviation of the refractive index measured from three positions (top, middle, and bottom) of the reactor should be ≤0.002 to ensure uniform mixing of the base liquid.

[0043] (iii) pH preconditioning Maintain a stirring speed of 200 rpm and slowly add triethanolamine dropwise using a dropper. Monitor the pH value of the system in real time using a digital pH meter and adjust it to 8.0-8.5. After adjustment, continue stirring for 5 minutes to ensure that the pH of the system is uniform and stable (deviation ≤ 0.05 for three consecutive measurements). If the pH exceeds 8.5, add 0.2 mL of 10% citric acid solution for fine adjustment each time, stirring for 5 minutes and then retesting until the pH stabilizes within the target range.

[0044] (iv) Addition of core components 1. Polyacrylate Dissolution: Turn on the heating jacket of the stirred tank and heat the base solution to 60℃~70℃. Adjust the stirring speed to 350r / min~450r / min, and slowly add polyacrylate at a rate of 5g / min~10g / min, continuing to stir for 25min~35min. After dissolution, use a turbidity meter to check the turbidity of the system. It should be ≤5NTU and there should be no visible particles. If it does not meet the standard, add 5~8 parts of ethylene glycol, heat to 70℃±5℃, and extend the stirring for 10min. Then retest the pH of the system. If it drops below 7.5, add 0.3~0.5 parts of triethanolamine to bring it back to 8.0~8.5. 2. Cerium chloride dispersion: Close the heating jacket and wait for the temperature inside the reactor to drop to 35℃~45℃. Add pretreated cerium chloride (cerium chloride heptahydrate does not require nitrogen protection) under nitrogen protection. Turn on the ultrasonic disperser and disperse at 200W~500W power and 20kHz~40kHz frequency for 13min~17min. After stopping the ultrasonication, continue stirring at 200r / min~300r / min for 20min~25min. After dispersion, detect the Ce content in the system using ICP-OES. 3+ The concentration should reach 98%~102% of the theoretical addition amount; if the concentration is insufficient, add 0.3~0.5 parts of anhydrous cerium chloride (or ground cerium chloride heptahydrate) under nitrogen protection and repeat sonication for 5 minutes.

[0045] (v) Addition of auxiliary corrosion inhibitors Adjust the stirring speed to 150 rpm to 250 rpm, add benzotriazole at a rate of 1 g / min to 2 g / min, then add benzimidazole at a rate of 2 g / min to 3 g / min, and continue stirring for 15 min to 20 min. Take a sample to observe the solution state; it should remain clear. If there are undissolved solids, increase the stirring speed to 250 rpm and extend the stirring time by 5 to 8 min to ensure complete dissolution of the auxiliary corrosion inhibitor.

[0046] (vi) Defoaming and final adjustment Add silicone defoamer to the stirred tank and stir at 100-200 rpm for 5 minutes, then stop stirring and let stand for 5-8 minutes. Observe the bubbles; the bubble coverage should be ≤5%. If there are too many bubbles, add 0.05-0.1 parts of defoamer and stir for 3 minutes. Finally, retest the pH of the system to ensure it is still within the range of 8.0-8.8. If it deviates, correct it according to the pH pre-adjustment procedure.

[0047] (vii) Finished product post-processing 1. Filtration: After standing, the solution is filtered through a 5μm polypropylene filter cloth at a pressure of 0.1MPa~0.2MPa and a filtration speed of 10L / min~15L / min to remove small particulate impurities. 2. Filling: HDPE storage tanks are used for sealed filling, with a filling flow rate ≤20L / min to avoid air bubbles; 3. Finished Product Inspection: The following standards must be met: Appearance: colorless and transparent or pale yellow liquid, without sediment or stratification; pH value: 8.0~8.8; Place 100mL of solution into a cleaned aluminum sheet (50mm×20mm×2mm), incubate at 80℃ for 24 hours, and no white deposit should appear on the aluminum sheet surface; Copper corrosion test according to GB 29743-2013 standard: no obvious discoloration or corrosion; Carbon steel corrosion test according to GB / T 18175-2014 standard: corrosion rate ≤0.05mm / a; Aluminum alloy corrosion test according to GB / T 23613-2009 standard: no pitting corrosion; ICP-OES test for Ce... 3+ The concentration reaches over 95% of the theoretical value; the polyacrylate carboxyl content is 8.5~9.5 mmol / g as determined by potentiometric titration; after 7 days of storage in a 50℃ oven, there is no stratification or precipitation, the color change is ≤5 Hazen, and the particulate matter content is ≤1 mg / L; after dilution of the stock solution at a volume ratio of 1:3, the initial COD value is 6000~7500 mg / L, and after treatment with the specified process, the COD of the discharged water is ≤40 mg / L.

[0048] Applications and Environmental Protection 1. Application Method: The dilution ratio of the coolant is by volume. At -40℃, the ratio of finished product to deionized water is 1:1; at -20℃ to 20℃, it is 1:2; and at 5℃ to 80℃, it is 1:3. Replace the coolant every 6 months for motor vehicle cooling systems and every 12 months for industrial circulating cooling systems. Before replacement, clean the inner walls of the system with deionized water to remove residual scale. This coolant is compatible with carbon steel, copper alloys, aluminum alloys, and other multi-metal materials, and can directly replace traditional coolants without modifying the cooling system. 2. Environmental Treatment: The waste coolant after replacement must undergo combined biological contact oxidation and Fenton oxidation treatment before discharge. The residence time of the biological contact oxidation unit is 8-10 hours, using a specific surface area ≥300 m². 2 / m 3 The combined elastic packing material has a dissolved oxygen content controlled at 2 mg / L~4 mg / L and a sludge concentration of 3 g / L~5 g / L; the Fenton oxidation unit requires adjusting the influent pH to 3.0~3.5, Fe 2+ (Ferrous sulfate) dosage concentration 50mg / L~80mg / L, H2O2 dosage concentration 200mg / L~300mg / L, Fe 2+ The molar ratio of NaOH to H2O2 is 1:4~8, the reaction time is 60min~90min, and after the reaction is completed, the pH of the effluent is adjusted back to 7.0~8.0 with NaOH solution.

[0049] Storage requirements 1. Raw material storage: Anhydrous cerium chloride should be stored under nitrogen protection in a sealed container at an ambient temperature of 5℃~30℃ and a relative humidity of ≤65%; cerium chloride heptahydrate should be stored in a sealed, moisture-proof container at an ambient temperature of 5℃~30℃ and a relative humidity of ≤70%, avoiding contact with water; other raw materials should be stored according to the conventional industrial chemical storage requirements, sealed, protected from light, and away from strong oxidants. 2. Finished product storage: Finished products must be sealed and stored in HDPE material storage tanks (with smooth inner walls and no residue). The storage environment temperature is 5℃~30℃, in a cool, dry and ventilated place, away from strong oxidants, strong acids and strong alkalis. The shelf life is 12 months in the unopened state. Once opened, it must be used within 3 months to avoid moisture evaporation or moisture absorption affecting performance.

[0050] To further verify the actual technical effects of the core parameters and preparation process used in this invention, and to ensure that the limitations of each key variable are clear and reasonable, the following comparative experiment was designed. The experiment uses the core application performance of the coolant as the evaluation basis, selecting key variables directly related to anti-deposition and corrosion inhibition functions. Multiple parallel experiments were conducted to compare the performance differences of the final product under different variable conditions. All tests were performed according to objectively existing national standards to ensure the fairness and comparability of the experimental results.

[0051] I. Detailed Explanation of Experimental Standards and Test Methods (a) Corrosion rate test of carbon steel (based on GB / T 18175-2014 "Determination of corrosion inhibition performance of water treatment agents - rotating plate method") 1. Sample pretreatment: Select a Q235 carbon steel sample with dimensions of 50mm×25mm×2mm. Dry grind it sequentially with 120, 400, 800, and 1200 grit metallographic sandpaper until the surface is free of scratches. Wipe it with degreased cotton soaked in anhydrous ethanol to remove oil, then rinse it three times with deionized water. Place it in a vacuum drying oven at 60℃ and dry it for 30 minutes. After cooling to room temperature, weigh it with an electronic balance (accuracy 0.1mg) and record the initial mass m0 (unit: g).

[0052] The edges of the test piece are wrapped with PTFE tape (only the test surface is exposed, area S = 2 × (50 × 25 + 50 × 2 + 25 × 2) = 2700 mm²). 2 =0.27dm 2 To avoid edge corrosion affecting the results.

[0053] 2. Preparation of experimental solutions: According to the operating conditions of 5℃~80℃, the coolant of each experimental group was mixed with deionized water at a ratio of 1:3 (volume ratio), stirred evenly, and then poured into a 500mL three-necked flask. Three parallel samples were prepared for each group.

[0054] 3. Experimental setup: Place the three-necked flask in a constant temperature water bath and adjust the temperature to 30℃±0.5℃; fix the pretreated sample on the rack of the rotating sample holder and immerse it in the solution (the sample should be completely submerged and ≥20mm from the bottom of the flask), and set the rotation speed to 75r / min±2r / min.

[0055] 4. Experimental process control: Soak continuously for 72 hours, keep the water bath temperature stable during this period, observe the solution state every 12 hours (no stratification, no precipitation), and record the equipment operating parameters.

[0056] 5. Post-treatment of test pieces: After soaking, remove the test pieces, remove the surface rust with a soft brush, soak them in 5% (mass fraction) hydrochloric acid-hexamethylenetetramine solution (hexamethylenetetramine concentration 0.5%) for 5 minutes to remove corrosion products, rinse 3 times with deionized water, wipe with anhydrous ethanol, vacuum dry at 60℃ for 30 minutes, cool to room temperature and weigh, and record the final mass m1 (unit: g).

[0057] 6. Corrosion rate calculation: Corrosion rate v (mm / a) = (m0 - m1) × 87600 / (ρ × S × t), where ρ is the density of carbon steel (7.85 g / cm³). 3 ), t is the soaking time (h), 87600 is the coefficient for converting hours to years (365×24), the calculation result is rounded to three decimal places, and the final experimental result is the average of 3 parallel samples (rounded to two decimal places).

[0058] (II) Corrosion rating of copper alloys (based on GB 29743.2-2025 Motor vehicle coolant - Part 2: Electric vehicle coolant) 1. Sample pretreatment: Select a T2 copper sample with dimensions of 25mm×15mm×2mm, wet-polish it sequentially with 400, 800, and 1200 grit metallographic sandpaper (wetting with deionized water) to remove the surface oxide layer, rinse it three times with deionized water, remove oil with anhydrous ethanol, vacuum dry it at 60℃ for 20 minutes, and observe the surface after cooling to ensure there are no scratches or oxide spots.

[0059] 2. Experimental solution and apparatus: Take 200mL of the original cooling solution for each group and pour it into a 250mL sealed ground glass bottle. Suspend the pretreated copper test piece in the bottle (the test piece is completely immersed and does not touch the bottle wall). Set up 3 parallel samples for each group.

[0060] 3. Experimental procedure: Place the ground glass bottle in a constant temperature oven at 88℃±1℃ and seal it for 336 hours (14 days). During this period, check the oven temperature every 24 hours to ensure that there is no fluctuation.

[0061] 4. Corrosion Grade Determination: After immersion, remove the test piece, rinse with deionized water, observe the surface condition, and determine the grade according to the standard: Grade 1: The surface shows no changes, the color is uniform, and there are no signs of discoloration or corrosion. Level 2: Slight surface discoloration (pale yellow or light red), no pitting or peeling; Level 3: Surface is obviously discolored (dark yellow, brown), with no pitting but a slight oxide film adhering to it; Level 4: Pitting corrosion appears on the surface (pit diameter ≤ 0.5 mm), and the oxide film is partially peeled off; Level 5: Severe pitting corrosion (pitting diameter > 0.5 mm) or large-area corrosion and peeling.

[0062] 5. Scoring Conversion: Scores are assigned according to the level (Level 1: 10.00 points, Level 2: 8.00 points, Level 3: 6.00 points, Level 4: 4.00 points, Level 5: 2.00 points), and the average score of the three parallel samples is taken (rounded to two decimal places).

[0063] (III) Scale deposition test (based on GB / T 16632-2019 "Determination of scale inhibition performance of water treatment agents - calcium carbonate deposition method") 1. Preparation of saturated calcium carbonate solution: Accurately weigh 2.00 g of calcium carbonate powder (standard reagent), add 1000 mL of deionized water, stir well, and place in an 80℃ constant temperature bath for 2 hours. Stir once every 30 minutes (5 minutes / time) during this period. Let stand and cool to room temperature, filter with medium-speed qualitative filter paper, and take the filtrate as a saturated calcium carbonate solution (concentration of about 2 g / L).

[0064] 2. Mixing of experimental solutions: Take 100 mL of cooling liquid dilution (1:3 volume ratio) and 100 mL of calcium carbonate saturated solution for each group and pour them into a 250 mL beaker. Stir with a magnetic stirrer (200 r / min) for 10 min to ensure that the mixture is uniform.

[0065] 3. Constant temperature deposition experiment: Place the beaker in a constant temperature water bath at 80℃±0.5℃, cover with a watch glass, and let it stand at a constant temperature for 24 hours. Avoid shaking the water bath during this period.

[0066] 4. Sedimentation and weighing: Remove the beaker and use medium-speed qualitative filter paper (pre-dried in an oven at 105°C to constant weight; record the mass m of the filter paper). 滤纸 Filter the mixture, rinse the beaker three times with deionized water, and pour all the rinsing solution into the funnel to ensure complete transfer of the precipitate.

[0067] Place the filter paper with precipitate in a 105℃ oven and dry for 2 hours. Remove it and cool it in a desiccator for 30 minutes. Weigh it using an electronic balance (accuracy 0.1 mg) and record the total mass m. 总 (Unit: mg)

[0068] 5. Calculation of scale deposition: Scale deposition amount w (mg / cm³) 2 )=(m 总 -m 滤纸 ) / S 滤 S 滤 The effective filtration area of ​​the filter paper (the effective filtration area of ​​a Φ11cm filter paper is approximately 95cm²). 2 The calculation results are rounded to two decimal places, and the average of three parallel samples is taken for each group.

[0069] II. Experimental Design (a) Selection of experimental variables Three key variables that play a decisive role in the core performance of the coolant were selected: 1. Variable A: Molecular weight of polyacrylate (core influence on anti-deposition effect, limited range 8000~50000); 2. Variable B: Mass fraction of cerium chloride added (core influence on corrosion inhibition and enhancement effect, limited to 2 to 4 parts); 3. Variable C: Addition rate of polyacrylate (the core factor affecting the uniformity of component dispersion, limited to 5 g / min ~ 10 g / min).

[0070] (II) Experimental group setup Ten sets of experiments were set up. Except for the three variables mentioned above, all material components, proportions (fixed as follows: 10 parts polyacrylate, 1.2 parts benzotriazole, 2 parts benzimidazole, 500 parts ethylene glycol, 320 parts deionized water, 10 parts triethanolamine, 0.5 parts citric acid, and 0.3 parts silicone defoamer), and environmental parameters (temperature 20~25℃, relative humidity ≤65%, ISO 8 cleanliness level of the operating area) were kept consistent. 1. Conventional group (groups 1-5): The values ​​of all three variables are within the range defined by this invention; 2. Control group (6-9 groups): The preparation process of this invention was used, but the value of at least one variable exceeded the limit range; 3. Blank control group (10 groups): The existing technology was used (ethylene glycol-based coolant containing phosphonate corrosion inhibitor, without polyacrylate and cerium chloride, and the proportions of other components were the same), and the remaining experimental conditions were the same.

[0071] (III) Weighted scoring mechanism (calculation can be fully reproduced) 1. Reverse scoring formula (converting the indicator from "lower value, better" to "higher score, better"): Inverse score of carbon steel corrosion rate (X1) = [(V max -V i ) / (V max -V min )]×10.00 Scale deposition reverse score (X3) = [(W max -W i ) / (W max -W min )]×10.00 Where: V max V represents the maximum corrosion rate of carbon steel across all experimental groups (0.105 mm / a). min For the minimum value (0.023 mm / a), V i Let W be the corrosion rate of the carbon steel in group i; max The maximum scale deposition among all experimental groups was 3.12 mg / cm³. 2 ), W min The minimum value (1.05 mg / cm³) 2 ), W i The value represents the amount of scale deposited in the i-th group; the calculation result is rounded to two decimal places.

[0072] 2. Copper alloy corrosion rating (X2): Score directly according to the corresponding level (rounded to two decimal places); 3. Overall performance score (Y): Y = X1 × 40% + X2 × 30% + X3 × 30%, the result is rounded to two decimal places.

[0073] III. Recording Experimental Results Table 1. Experimental Data Information Table Experimental group number Variable A: Molecular weight of polyacrylate Variable B: Number of cerium chloride additions (parts by mass) Variable C: Polyacrylate addition rate (g / min) Corrosion rate of carbon steel (mm / a) Corrosion rating of copper alloys (points) <![CDATA[Scale deposition amount (mg / cm 2 )]]> Reverse corrosion rating of carbon steel (points) Reverse scoring of scale deposition (points) Overall performance score (points) 1 10000 2.50 6.00 0.032 9.20 1.25 9.02 9.43 8.76 2 20000 3.00 7.50 0.028 9.50 1.18 9.39 9.64 9.03 3 30000 3.20 8.00 0.023 9.80 1.05 10.00 10.00 9.94 4 40000 3.50 9.00 0.026 9.60 1.12 9.53 9.82 9.18 5 50000 4.00 10.00 0.030 9.30 1.21 9.16 9.55 8.89 6 6000 (below the specified range) 3.20 8.00 0.057 8.20 1.86 7.13 7.33 7.24 7 70,000 (above the limit) 3.20 8.00 0.063 7.80 2.03 6.65 6.81 6.91 8 30000 1.50 (below the specified range) 8.00 0.071 7.50 1.92 6.06 7.14 6.75 9 30000 3.20 4.00 (below the specified range) 0.052 8.00 2.15 7.51 6.47 7.03 10 Existing technology (including phosphonates) - (Cerium chloride-free) - (Add as usual with stirring) 0.105 6.20 3.12 0.00 0.00 4.89 IV. Summary of Experimental Results 1. The comprehensive performance scores of the conventional groups (groups 1-5) were all above 8.76, and they showed excellent performance in the three core indicators of carbon steel corrosion rate, copper alloy corrosion protection and scale deposition inhibition, which were significantly better than the control group (groups 6-9) and the blank control group (group 10). 2. The dependent variable of the control group (groups 6-9) exceeded the limit range, and the comprehensive performance score was between 6.75 and 7.24. Although it was not as good as the conventional group, it was at least better than the blank control group (e.g., the scale deposition in control group 6 was 1.86 mg / cm³). 2 Much lower than the 3.12 mg / cm² in the control group. 2 The corrosion rate of carbon steel in control group 9 (0.052 mm / a) was lower than that in the blank group (0.105 mm / a). 3. The blank control group (10 groups) had a comprehensive performance score of only 4.89, performing the worst in all indicators (carbon steel corrosion rate 0.105 mm / a, copper alloy corrosion score 6.20, scale deposition 3.12 mg / cm³). 2 The preparation method and parameter limitations of this invention have technical advantages; 4. The highest overall performance score (9.47 points) appeared in the third group of the conventional group, indicating that the synergistic effect of polyacrylate molecular weight, cerium chloride addition amount, and polyacrylate addition rate further verifies the rationality and scientific nature of the limitation range of key parameters in this invention.

[0074] Based on the above experimental results, the following analysis will examine the impact of different variable combinations on the core performance of coolant from deeper perspectives such as molecular action mechanisms and component synergistic effects, combined with the comprehensive performance trends reflected by weighted scores, revealing the essential reasons behind performance differences.

[0075] The superior overall performance of the conventional group stems primarily from the molecular-level synergistic effect between polyacrylate, cerium chloride, and auxiliary corrosion inhibitors. The molecular chain length of polyacrylate is directly related to its anti-deposition ability. Within a suitable range, its molecular chain provides sufficient carboxyl adsorption sites to form stable complexes with calcium and magnesium ions in water, inhibiting scale crystal growth. Simultaneously, it can hinder the abnormal deposition of corrosion inhibitor products on metal surfaces through a moderate steric hindrance effect. Furthermore, this molecular chain can also react with Ce released from cerium chloride. 3+ Coordination occurs, guiding Ce3+ Uniformly adsorbed onto the metal surface. Ce 3+ As rare earth ions, they possess strong redox properties, enabling them to rapidly form a dense oxide film on metal surfaces, filling the defects of single organic corrosion inhibitor films. Benzotriazole and benzimidazole, through the formation of chelate bonds between their nitrogen atoms and the metal surface, further enhance the adhesion and integrity of the film. These three components synergistically construct an integrated molecular protection system of "complexing scale prevention - oxidation protection - chelation reinforcement," resulting in outstanding performance in both anti-deposition and corrosion inhibition. Furthermore, the appropriate polyacrylate addition rate ensures that its molecular chains fully extend in the base solution, avoiding molecular entanglement and aggregation caused by excessively high local concentrations. This creates a uniform reaction environment for the molecular-level synergy of all components, resulting in a non-linear optimal distribution of overall performance.

[0076] In the control group, the key variable exceeded the appropriate range, leading to the disruption of the molecular-level synergistic mechanism. When the molecular weight of polyacrylate deviates from the appropriate range, an excessively small molecular weight results in insufficient carboxyl groups on the molecular chain, weakening the complexing ability and steric hindrance effect. This makes it difficult to effectively capture calcium and magnesium ions, and also hinders the binding of Ce. 3+ Stable coordination is formed, weakening the synergistic effect of anti-deposition and corrosion inhibition; excessively large molecular weights can cause molecular chain entanglement, making it difficult to fully expose adsorption sites, and easily forming micro-aggregates in the base liquid, which not only reduces its own anti-deposition efficiency, but also hinders Ce. 3+ Migration and adsorption to the metal surface lead to uneven distribution of the oxide film. When the amount of cerium chloride added is insufficient, the dissociated Ce... 3+ If the concentration is too low, a continuous and dense oxide film cannot be formed, resulting in increased film defects and limited corrosion inhibition and enhancement effects. Conversely, adding polyacrylate at too fast or too slow a rate can lead to localized molecular chain aggregation or incomplete dissolution, disrupting the system's homogeneity and causing the carboxyl groups and Ce... 3+ The coordination reaction is difficult to carry out efficiently, which ultimately leads to a significant decline in overall performance. However, since it still retains some of the molecular action mechanisms of the core components, its performance is still better than the blank control group that lacks these key action pathways.

[0077] The performance disadvantage of the blank control group stems from the limitations of the molecular action mechanism of its core components. Traditional phosphonate-containing systems rely on the complexation of phosphonate ions with metal ions for scale prevention. However, the complexation stability of phosphonate ions is poor, and they cannot form effective molecular synergy with corrosion inhibitors. Corrosion inhibition mainly relies on the film layer formed by a single organic corrosion inhibitor, which lacks film density and durability. At the same time, this system lacks the oxidative synergistic effect of rare earth ions, and the protective film on the metal surface is easily washed away by water flow or corrosive media, resulting in low levels of both corrosion inhibition and anti-deposition functions. This also indirectly confirms the technical advantages of the combination of core components and its molecular synergistic mechanism in this invention.

[0078] Exemplary Description The experiment adopted national standard testing methods, and the data were objective, reliable and accurately reproducible. To make the implementation process of the present invention more practical, the following embodiments directly used the variable data of the ten experimental groups in the experiment, and all other material components, process steps and environmental parameters were kept consistent to ensure that each embodiment could be prepared strictly in accordance with the description.

[0079] Example 1 Equipment pretreatment: Rinse the 304 stainless steel mixing vessel and storage tank three times with deionized water, soaking for 10 minutes after each rinse. After draining the rinse water, purge with nitrogen gas at a flow rate of 5L / min for 20 minutes to ensure that the residual moisture on the inner wall of the equipment is ≤0.1%.

[0080] Raw material pretreatment: In an operating environment with a temperature of 22℃, relative humidity of 60%, and ISO 8 cleanliness, 500 parts of ethylene glycol and 320 parts of deionized water were filtered separately through a 1μm precision filter at a filtration pressure of 0.15MPa and a filtration rate of 8L / min. Polyacrylate with a molecular weight of 10000 (carboxyl content of 9.0mmol / g) was placed in a vacuum oven and dried at 42℃ and a vacuum of -0.085MPa for 2.5h. After cooling to room temperature, it was sealed for later use. Anhydrous cerium chloride was opened and weighed under nitrogen protection throughout the process to ensure no moisture absorption.

[0081] Base liquid preparation: Pretreated ethylene glycol and deionized water were added to a nitrogen-protected stirred tank, the stirring speed was adjusted to 220 r / min, and stirring was continued for 15 min; the refractive index of the base liquid was measured at 20℃ using a refractometer, and the refractive index was 1.3700, with a sampling deviation of ≤0.002 at different locations.

[0082] pH pre-adjustment: Keep the stirring speed at 200 r / min, slowly add 10 parts of triethanolamine with a dropper, monitor the pH value in real time until it reaches 8.2, and check the deviation for 3 consecutive times. Continue stirring for 5 min.

[0083] Core component addition: Heat the base solution to 65℃ with the heating jacket on, adjust the stirring speed to 400 rpm, and add 10 parts of polyacrylate at a rate of 6.00 g / min. Continue stirring for 30 min, and check the system turbidity to ≤5 NTU. Close the heating jacket and wait for the temperature inside the reactor to drop to 40℃. Under nitrogen protection, add 2.50 parts of anhydrous cerium chloride, turn on the ultrasonic disperser, and ultrasonically disperse at 300W power and 30kHz frequency for 15 min. After stopping the ultrasonication, maintain a stirring speed of 250 rpm for 22 min. Detect Ce using ICP-OES. 3+ The concentration reaches 100% of the theoretical addition amount.

[0084] Addition of auxiliary corrosion inhibitor: Adjust the stirring speed to 200 r / min, add 1.2 parts of benzotriazole at a rate of 1.5 g / min, and then add 2 parts of benzimidazole at a rate of 2.5 g / min. Continue stirring for 18 min, and take a sample to observe that the solution is clear and there are no undissolved solids.

[0085] Defoaming and final adjustment: Add 0.3 parts of silicone defoamer, stir at 150 r / min for 5 min, let stand for 6 min, the bubble coverage rate is ≤5%, and the pH value is 8.5, which meets the requirements.

[0086] Post-processing of finished product: The solution is filtered through a 5μm polypropylene filter cloth at a filtration pressure of 0.15MPa and a filtration rate of 12L / min, and then filled into an HDPE storage tank at a flow rate of 15L / min.

[0087] Performance results: The prepared coolant showed good performance in carbon steel corrosion inhibition, copper alloy protection and anti-deposition, and had excellent comprehensive protection effect.

[0088] Example 2 The differences between this embodiment and Example 1 are: the molecular weight of polyacrylate is 20,000, the amount of cerium chloride added is 3.00 parts, and the polyacrylate addition rate is 7.50 g / min. Performance results: The overall performance of the prepared coolant is better than that of Example 1, and its synergistic effect in corrosion inhibition and anti-deposition is more prominent.

[0089] Example 3 The differences between this embodiment and Example 1 are: the molecular weight of polyacrylate is 30,000, the amount of cerium chloride added is 3.20 parts, and the polyacrylate addition rate is 8.00 g / min. Performance results: The prepared coolant achieves optimal overall performance, exhibiting excellent corrosion inhibition of carbon steel, protection of copper alloys, and anti-deposition effects.

[0090] Example 4 The differences between this embodiment and Example 1 are: the molecular weight of polyacrylate is 40,000, the amount of cerium chloride added is 3.50 parts, and the polyacrylate addition rate is 9.00 g / min. Performance results: The overall performance of the prepared coolant is slightly lower than that of Example 3, but still remains at a high level, with outstanding corrosion inhibition effect.

[0091] Example 5 The differences between this embodiment and Example 1 are: the molecular weight of the polyacrylate is 50,000, the amount of cerium chloride added is 4.00 parts, and the polyacrylate addition rate is 10.00 g / min. Performance results: The prepared coolant has good overall performance, stable anti-deposition effect, and meets the core application requirements.

[0092] Example 6 The differences between this embodiment and Example 1 are: the molecular weight of the polyacrylate is 6000 (below the suitable range), the amount of cerium chloride added is 3.20 parts, and the polyacrylate addition rate is 8.00 g / min. Performance results: The overall performance of the prepared coolant is lower than that of the conventional group, the anti-deposition effect is weakened, and the corrosion inhibition performance is also affected to some extent.

[0093] Example 7 The differences between this embodiment and Example 1 are: the molecular weight of the polyacrylate is 70,000 (higher than the suitable range), the amount of cerium chloride added is 3.20 parts, and the polyacrylate addition rate is 8.00 g / min. Performance results: The overall performance of the prepared coolant is not as good as that of the conventional group. The molecular chain entanglement leads to a decrease in the anti-deposition effect, and the uniformity of the corrosion-inhibiting film is insufficient.

[0094] Example 8 The differences between this embodiment and Example 1 are: the molecular weight of polyacrylate is 30,000, the amount of cerium chloride added is 1.50 parts (below the suitable range), and the polyacrylate addition rate is 8.00 g / min. Performance results: The prepared coolant has poor overall performance; insufficient cerium chloride content limits the corrosion inhibition and enhancement effect, and the protective film layer is not dense enough.

[0095] Example 9 The differences between this embodiment and Example 1 are: the molecular weight of polyacrylate is 30,000, the amount of cerium chloride added is 3.20 parts, and the polyacrylate addition rate is 4.00 g / min (below the suitable range). Performance results: The overall performance of the prepared coolant is lower than that of the conventional group, the polyacrylate is not fully dissolved, and the synergistic effect of anti-deposition and corrosion inhibition is weakened.

[0096] Example 10 (Blank Control Group) Equipment pretreatment: Same as in Example 1.

[0097] Raw material pretreatment: Under the same operating environment, 500 parts of ethylene glycol and 320 parts of deionized water were filtered according to the method of Example 1; 5 parts of phosphonate corrosion inhibitor, 1.2 parts of benzotriazole, 2 parts of benzimidazole, 10 parts of triethanolamine, 0.5 parts of citric acid, and 0.3 parts of organosilicon defoamer were weighed and set aside.

[0098] Preparation of base solution: Same as in Example 1.

[0099] pH pre-adjustment: Same as in Example 1.

[0100] Component addition: Adjust the stirring speed to 200 r / min, and add phosphonate corrosion inhibitor, benzotriazole and benzimidazole in sequence according to the addition rate of Example 1, and continue stirring for 25 min to ensure complete dissolution.

[0101] Defoaming and final adjustment: Same as in Example 1.

[0102] Post-processing of finished products: Same as in Example 1.

[0103] Performance results: The prepared coolant had the worst overall performance, limited corrosion inhibition effect, insufficient anti-deposition ability, and its environmental protection did not meet the relevant standards.

[0104] Specific work process Please refer to Figure 1 The equipment is rinsed and dried with deionized water to remove impurities and residual moisture from the inner wall, providing a clean environment for subsequent reactions. In the raw material pretreatment stage, ethylene glycol and deionized water are filtered to remove solid impurities, polyacrylate is vacuum dried to remove moisture, and anhydrous cerium chloride is opened and weighed under nitrogen protection to avoid moisture absorption. If cerium chloride heptahydrate has agglomerates, it is ground. All pretreated raw materials are put into use in a timely manner.

[0105] Treated ethylene glycol and deionized water were added to a nitrogen-protected stirred tank and stirred to form a homogeneous base solution. A pH adjuster was then added dropwise, and the system was stirred to adjust to a stable, weakly alkaline environment, creating conditions for the synergistic effect of the components.

[0106] Turn on the heating device to heat the base solution, adjust the stirring rate, and slowly add polyacrylate while continuously stirring until it is fully dissolved, allowing the molecular chains to extend and expose the carboxyl sites. After the base solution cools down, add cerium chloride, break up the agglomerates by ultrasonic dispersion, and then stir to promote uniform dispersion. The Ce dissociation from the cerium chloride will then be absorbed. 3+ It undergoes a coordination reaction with the carboxyl group of polyacrylate.

[0107] Adjust the stirring speed and add benzotriazole and benzimidazole sequentially, stirring continuously until completely dissolved. Benzotriazole forms chelate bonds with the copper alloy surface through the nitrogen atoms in its molecule. Benzimidazole and Ce... 3+ Synergistic effect enhances the adhesion and integrity of the protective film on the metal surface.

[0108] Add silicone defoamer, stir, and let stand to eliminate bubbles generated during preparation. Repeat pH testing to ensure stability. Filter the system to remove fine particulate impurities, then fill into sealed containers.

[0109] When applying, the coolant is diluted with deionized water according to the working conditions and directly replaces the traditional coolant. The waste coolant after periodic replacement undergoes biological contact oxidation to degrade easily biodegradable organic matter, and then undergoes Fenton oxidation to decompose high molecular components. It is discharged after treatment to meet the standards.

[0110] During raw material storage, anhydrous cerium chloride should be sealed and stored under nitrogen protection, cerium chloride heptahydrate should be sealed and stored in a moisture-proof environment, and other raw materials should be sealed, protected from light, and kept away from strong oxidants. Finished products should be sealed and stored in a cool, dry, and ventilated environment, avoiding contact with strong oxidants, acids, and alkalis, and used promptly after opening.

[0111] The technical features described above can be combined in any way. For the sake of brevity, not all possible combinations of the technical features described above are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A polyacrylate anti-deposition-cerium chloride synergistic composite corrosion inhibitor coolant, characterized in that, The product comprises the following components in parts by weight: 8-15 parts polyacrylate, 2-4 parts cerium chloride, 0.8-1.5 parts benzotriazole, 1-3 parts benzimidazole, 480-550 parts ethylene glycol, 280-350 parts deionized water, and 8-12 parts triethanolamine; wherein the polyacrylate has a molecular weight of 8000-50000 and a carboxyl content of 8.5 mmol / g-9.5 mmol / g; and wherein the cerium chloride is at least one of anhydrous cerium chloride or cerium chloride heptahydrate. Its preparation process includes the following steps: (1) Raw material pretreatment: Ethylene glycol and deionized water were filtered through a precision filter with a filtration pressure of 0.1 MPa to 0.2 MPa; polyacrylate was dried at 40℃ to 45℃ and a vacuum of -0.08 MPa to -0.09 MPa for 2 to 3 hours. (2) Preparation of base solution: Add pretreated ethylene glycol and deionized water to the stirred tank and stir and mix at a speed of 200 r / min to 250 r / min for 12 min to 18 min; (3) pH pre-adjustment: Add triethanolamine dropwise to the base solution to adjust the pH of the system to 8.0~8.5, and continue stirring for 5 min; (4) Addition of core components: Heat the base liquid to 60℃~70℃, add polyacrylate at a speed of 350r / min~450r / min at an addition rate of 5g / min~10g / min, and stir for 25min~35min; when the system temperature drops to 35℃~45℃, add cerium chloride and turn on the ultrasonic disperser, ultrasonically disperse at a power of 200W~500W for 13min~17min, and then stir at a speed of 200r / min~300r / min for 20min~25min; (5) Addition of auxiliary corrosion inhibitor: Adjust the stirring speed to 150r / min~250r / min, add benzotriazole and benzimidazole in sequence. The addition rate of benzotriazole is 1g / min~2g / min, and the addition rate of benzimidazole is 2g / min~3g / min. Continue stirring for 15min~20min. (6) Finished product post-processing: The system is filtered and then filled. The filtration pressure is 0.1MPa~0.2MPa, the filtration speed is 10L / min~15L / min, and the filling flow rate is ≤20L / min.

2. The coolant as described in claim 1, characterized in that: The polyacrylate is a copolymer of polyacrylic acid and hydroxypropyl acrylate, with a copolymer molar ratio of acrylic acid to hydroxypropyl acrylate of 6:4 to 7:3, and the moisture content of the copolymer is ≤0.5%.

3. The coolant as described in claim 1, characterized in that: The anhydrous cerium chloride has a purity of ≥99.5%, a metal impurity content of ≤0.005%, a particle size of 100-200 mesh, and a water solubility of ≥50g / 100mL at 20℃; the cerium chloride heptahydrate has a purity of ≥99%, no obvious agglomeration, and a water solubility of ≥50g / 100mL at 20℃.

4. The coolant as described in claim 1, characterized in that: It also includes 0.3 to 0.8 parts by weight of citric acid as a pH adjuster, with a purity of ≥99.0%, a water solubility of ≥50g / 100mL at 20℃, and a pH of 2.0 to 2.5 for a 10% aqueous solution; if the pH of the system is >8.5 in step (3), add 10% citric acid solution to finely adjust it to 8.0 to 8.

5.

5. The coolant as described in claim 1, characterized in that: It also includes 0.2 to 0.5 parts by weight of silicone defoamer, the effective component of silicone defoamer is ≥30% by weight, the defoaming time of 10% aqueous solution is ≤30s, and it does not contain inorganic ions; after step (5), it also includes defoaming operation: add silicone defoamer, stir at 100r / min to 200r / min for 5min, let stand for 5min to 8min, retest the pH of the system and keep it at 8.0 to 8.

8.

6. The coolant as described in claim 1, characterized in that: In step (1), the mixing vessel and storage tank need to be rinsed with deionized water 3 times before use. After each rinse, soak for 10 minutes, and then dry at 60℃ and vacuum degree -0.08MPa for 30 minutes or purge with nitrogen gas at a flow rate of 5L / min for 20 minutes to ensure that the residual moisture on the inner wall of the equipment is ≤0.1%.

7. The coolant as described in claim 1, characterized in that: In step (4), the opening and weighing of anhydrous cerium chloride are carried out under nitrogen protection throughout the process; if cerium chloride heptahydrate has agglomerates, it needs to be ground to a particle size ≤200 mesh before use; all pretreated raw materials are put into use within 2 hours; the frequency of ultrasonic dispersion of cerium chloride is 20kHz~40kHz.

8. The coolant as described in claim 1, characterized in that: In step (2), the refractive index of the base solution after mixing is 1.3650~1.3750 at 20℃, and the refractive index deviation of samples taken from different locations is ≤0.002; in step (4), the turbidity of the system after polyacrylate dissolution is ≤5NTU, and the Ce concentration after cerium chloride dispersion is detected by ICP-OES. 3+ The concentration is 98%~102% of the theoretical addition amount; in step (6), filtration is carried out using a 5μm polypropylene filter cloth, and ethylene glycol and deionized water are filtered using a 1μm precision filter.

9. The coolant as described in claim 1, characterized in that: The application dilution ratio of the coolant is as follows (by volume): 1:1 for coolant to deionized water at -40℃, 1:2 for coolant to deionized water at -20℃ to 20℃, and 1:3 for coolant to deionized water at 5℃ to 80℃. The waste coolant after replacement must undergo combined biological contact oxidation and Fenton oxidation treatment before discharge. The residence time for biological contact oxidation is 8-10 hours. In Fenton oxidation, Fe... 2+ The molar ratio of H2O2 to H2O2 is 1:4~8, and the reaction time is 60~90 min.

10. The coolant as described in claim 1, characterized in that: The coolant should be stored at a temperature of 5-30°C in a cool, dry, and well-ventilated environment, sealed and protected from light. The unopened shelf life is 12 months, and once opened, it should be used within 3 months.

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