Neutral rust remover and preparation method and application thereof

Abstract

The invention provides a neutral rust remover, and belongs to the technical field of metal surface treatment. The neutral rust remover is prepared from the following components in percentage by mass: 0.1 to 2 percent of penetrant, 0.1 to 1 percent of nonionic surfactant, 0.1 to 10 percent of fluorine compound, 0.1 to 2 percent of chlorine compound, 0.5 to 15 percent of amine compound, 0.1 to 2 percent of 2-acrylamide-2-methylpropanesulfonic acid, 0.1 to 2 percent of hydrolytic polymaleic anhydride, 0.1 to 2 percent of carboxylate-sulfonate-nonionic terpolymer, 5 to 20 percent of ammonium citrate, 0.1 to 1 percent of oxalic acid and 50 to 80 percent of water. By adopting the compatibility effect of various raw materials and utilizing the synergistic effect of the raw materials, the rust removal speed of the neutral rust remover is increased, the rust removal effect is more thorough, the surface color of a workpiece is not damaged, and the rust remover has a wide prospect in the field of rust removal of carbon steel and cast iron.

Description

Technical Field

[0001] The present invention relates to the technical field of metal surface treatment, and particularly to a neutral rust remover, a preparation method thereof, and an application thereof. Background Art

[0002] During the machining process, workpiece rusting, as a phenomenon that is difficult to avoid, directly affects the quality of the workpiece, resulting in defective products. The remedy for this is to remove the rust while ensuring that the workpiece body is not damaged and restoring the workpiece to its state during processing.

[0003] Currently, the use of hydrochloric acid-based rust removers is regarded as a mainstream rust removal method. Its significant advantage lies in its high rust removal efficiency, which can quickly remove rust and retain the gloss of the workpiece surface. However, hydrochloric acid, as a strong acid, has potential dangers and is accompanied by a strong pungent odor. In addition, it may cause hydrogen embrittlement in the metal structure of the workpiece, increasing the risk of structural embrittlement, and the subsequent rust prevention is difficult.

[0004] In contrast, neutral rust removers exhibit unique environmental protection advantages. Their mild chemical properties ensure no odor release and effectively avoid the risk of hydrogen embrittlement, providing more convenient conditions for subsequent rust prevention treatment. However, the rust removal process of neutral rust removers is relatively slow, usually taking more than 30 minutes. At the same time, the rust removal effect is often not thorough, and rust spots are relatively obvious, and it is easy to change the surface color of the workpiece during use. Summary of the Invention

[0005] The purpose of the present invention is to provide a neutral rust remover, a preparation method thereof, and an application thereof to overcome the problems existing in current neutral rust removers.

[0006] To achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:

[0007] The present invention provides a neutral rust remover, which includes the following components in terms of mass percentage:

[0008] Penetrant 0.1 - 2%, non-ionic surfactant 0.1 - 1%, fluorine compound 0.1 - 10%, chlorine compound 0.1 - 2%, amine compound 0.5 - 15%, 2-acrylamide-2-methylpropanesulfonic acid 0.1 - 2%, hydrolyzed polymaleic anhydride 0.1 - 2%, carboxylate-sulfonate-nonionic terpolymer 0.1 - 2%, ammonium citrate 5 - 20%, oxalic acid 0.1 - 1%, water 50 - 80%.

[0009] Preferably, the penetrant includes JFC-4.

[0010] Preferably, the non-ionic surfactant includes fatty alcohol polyoxyethylene ether-9.

[0011] Preferably, the fluorine compound includes ammonium bifluoride.

[0012] Preferably, the chlorine compound includes calcium chloride, sodium chloride, potassium chloride, magnesium chloride or ammonium chloride.

[0013] Preferably, the amine compound includes triethanolamine, diethylene glycol amine, isopropanolamine or triisopropanolamine.

[0014] The present invention provides a preparation method of the above neutral rust remover, comprising the following steps:

[0015] Under stirring conditions, mix a penetrant, a non-ionic surfactant, a fluorine compound, a chlorine compound, an amine compound, 2-acrylamide-2-methylpropanesulfonic acid, hydrolyzed polymaleic anhydride, a carboxylate-sulfonate-nonionic terpolymer, ammonium citrate, oxalic acid and water to obtain a mixture;

[0016] Mix the mixture with an amine compound and adjust the pH value to 6.0 - 6.5 to obtain a neutral rust remover.

[0017] Preferably, the stirring speed is 30 - 60 r / min and the time is 60 - 80 min.

[0018] The present invention also provides the application of the above neutral rust remover or the neutral rust remover prepared by the above preparation method in the field of rust removal of carbon steel and cast iron.

[0019] Advantages of the present invention:

[0020] The neutral rust remover of the present invention uses the compatibility of multiple raw materials and utilizes the synergistic effect between the raw materials to accelerate the rust removal speed of the neutral rust remover; among them, 2-acrylamide-2-methylpropanesulfonic acid, hydrolyzed polymaleic anhydride and carboxylate-sulfonate-nonionic terpolymer are added, which have a complexing and dispersing effect on iron ions and an inhibitory effect on iron oxide, can reduce the occurrence of reverse reactions, that is, accelerate the rust removal reaction and can also extend the service life of the rust remover; adding fluorine compounds and oxalic acid can accelerate the reaction of iron oxide; adding chlorine compounds can keep the surface of the workpiece bright; adding ammonium citrate can supplement the reducibility of the neutral rust remover, can improve the rust removal speed, and only 10 minutes are required for rust removal; adding an amine compound as an anti-rust and corrosion inhibitor component can ensure that it is not easy to rust again after rust removal and is beneficial to the rinsing and rust prevention of the workpiece after rust removal.

[0021] In addition, the present invention does not use phosphorus-containing compounds and can keep the original color of the workpiece surface; the neutral rust remover of the present invention is safe, environmentally friendly, efficient and easy to operate, can significantly improve the rust removal effect of the neutral rust remover, has a fast rust removal speed, a thorough rust removal effect, a uniform workpiece surface, and is easier for post-treatment, and can be used for rust removal of carbon steel and cast iron. Description of the Drawings

[0022] Figure 1 Schematic diagram of the carbon steel plate after rust removal in Example 1;

[0023] Figure 2 Schematic diagram of the carbon steel plate after rust removal in Comparative Example 1. Detailed implementation mode

[0024] The present invention provides a neutral rust remover, which comprises the following components in terms of mass percentage:

[0025] Penetrant 0.1 - 2%, non-ionic surfactant 0.1 - 1%, fluorine compound 0.1 - 10%, chlorine compound 0.1 - 2%, amine compound 0.5 - 15%, 2-acrylamide-2-methylpropanesulfonic acid 0.1 - 2%, hydrolyzed polymaleic anhydride 0.1 - 2%, carboxylate-sulfonate-nonionic terpolymer 0.1 - 2%, ammonium citrate 5 - 20%, oxalic acid 0.1 - 1%, water 50 - 80%.

[0026] In the neutral rust remover of the present invention, the mass fraction of the penetrant is preferably 0.1 - 2%, more preferably 0.1 - 1%; in the present invention, the penetrant preferably includes JFC-4. The addition of the penetrant can make the agent quickly penetrate into the rust and accelerate the reaction with the rust.

[0027] In the neutral rust remover of the present invention, the mass fraction of the non-ionic surfactant is preferably 0.1 - 1%, more preferably 0.1 - 0.5%; in the present invention, the non-ionic surfactant preferably includes fatty alcohol polyoxyethylene ether-9; the addition of the surfactant can not only increase the permeability and wettability, but also be used when the workpiece surface is oily, eliminating the need for pre-degreasing and reducing the rust removal process.

[0028] In the neutral rust remover of the present invention, the mass fraction of the fluorine compound is preferably 0.1 - 10%, more preferably 2 - 10%; in the present invention, the fluorine compound preferably includes ammonium bifluoride; the addition of the fluorine compound utilizes the synergistic effect of fluoride ions and ammonium ions on the reaction of iron oxide to accelerate the rust removal speed of the neutral rust remover.

[0029] In the neutral rust remover of the present invention, the mass fraction of the chlorine compound is preferably 0.1 - 2%, more preferably 0.2 - 2%; in the present invention, the chlorine compound preferably includes calcium chloride, sodium chloride, potassium chloride, magnesium chloride or ammonium chloride, more preferably includes calcium chloride or potassium chloride.

[0030] In the neutral rust remover of the present invention, the mass fraction of the amine compound is preferably 0.5 - 15%, more preferably 4 - 15%; in the present invention, the amine compound preferably includes triethanolamine, diethylene glycol amine, isopropanolamine or triisopropanolamine, more preferably includes triethanolamine, diethylene glycol amine or isopropanolamine.

[0031] In the neutral rust remover of the present invention, the mass fraction of 2-acrylamide-2-methylpropanesulfonic acid (AMPS) is preferably 0.1-2%, and more preferably 0.1-1%.

[0032] In the neutral rust remover of the present invention, the mass fraction of hydrolyzed polymaleic anhydride (HPMA) is preferably 0.1-2%, and more preferably 0.5-2%.

[0033] In the neutral rust remover of the present invention, the mass fraction of the carboxylate-sulfonate-nonionic terpolymer (TH-3100) is preferably 0.1-2%, and more preferably 0.5-2%.

[0034] In the neutral rust remover of the present invention, the mass fraction of ammonium citrate is preferably 5-20%, and more preferably 10-15%.

[0035] In the neutral rust remover of the present invention, the mass fraction of oxalic acid is preferably 0.1-1%, and more preferably 0.3-0.5%.

[0036] In the neutral rust remover of the present invention, the mass fraction of water is preferably 50-80%, and more preferably 50-74.4%.

[0037] The present invention provides a method for preparing the above neutral rust remover, comprising the following steps:

[0038] Under stirring conditions, mix a penetrant, a nonionic surfactant, a fluorine compound, a chlorine compound, an amine compound, 2-acrylamide-2-methylpropanesulfonic acid, hydrolyzed polymaleic anhydride, a carboxylate-sulfonate-nonionic terpolymer, ammonium citrate, oxalic acid and water to obtain a mixture;

[0039] Mix the mixture with an amine compound and adjust the pH value to 6.0-6.5 to obtain a neutral rust remover.

[0040] Preferably, water is added to a plastic stirring kettle in the present invention, stirring is started, and under stirring conditions, a penetrant, a nonionic surfactant, ammonium citrate, a fluorine compound, a chlorine compound, oxalic acid, acrylamide-2-methylpropanesulfonic acid, hydrolyzed polymaleic anhydride, and a carboxylate-sulfonate-nonionic terpolymer are successively added to the plastic stirring kettle, and stirred for 60-80 min until the materials are completely dissolved to obtain a mixture.

[0041] In the present invention, the rotation speed of the stirring is preferably 30-60 r / min, more preferably 40-50 r / min, the time is preferably 60-80 min, and more preferably 70 min.

[0042] The present invention preferably adds an amine compound to the mixture for neutralization and preferably adjusts the pH value to 6.0 - 6.5, more preferably 6.1 - 6.3, to obtain a neutral rust remover.

[0043] The present invention also provides the application of the above-mentioned neutral rust remover or the neutral rust remover prepared by the above-mentioned preparation method in the field of rust removal of carbon steel and cast iron; in the present invention, the method of the application preferably includes the following steps: soaking a carbon steel plate or a cast iron workpiece with surface rust in the neutral rust remover, ultrasonicating for 10 min at 45 - 50 °C, then rinsing with clear water, and performing an anti-rust treatment on the rust-removed workpiece. The anti-rust treatment can select a general-purpose water-based anti-rust agent or anti-rust oil according to process requirements.

[0044] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0045] Example 1

[0046] The neutral rust remover provided in this example includes the following raw materials by mass fraction: JFC - 40.1%; fatty alcohol polyoxyethylene ether - 90.5%, ammonium bifluoride 2%, calcium chloride 0.2%, triethanolamine 4%, 2-acrylamide-2-methylpropanesulfonic acid 1%, hydrolyzed polymaleic anhydride 2%, carboxylate-sulfonate-nonionic terpolymer 0.5%, ammonium citrate 15%, oxalic acid 0.3%, water 74.4%;

[0047] Add water to a plastic stirring kettle, start stirring, and sequentially add JFC-4, fatty alcohol polyoxyethylene ether-9, ammonium citrate, ammonium bifluoride, calcium chloride, oxalic acid, AMPS, HPMA, and TH-3100 to the plastic stirring kettle at 40 r / min, and stir for 70 min to obtain a mixture;

[0048] Add triethanolamine to the mixture and adjust the pH value to 6.2 to obtain a neutral rust remover.

[0049] Application Example 1

[0050] The neutral rust remover is used in the form of the original solution. Soak the rusty carbon steel plate in the original solution of the neutral rust remover in Example 1, ultrasonicate for 10 min at 45 °C, then rinse with clear water, and finally use a general-purpose water-based anti-rust agent for anti-rust treatment.

[0051] Comparative Example 1

[0052] The difference from Application Example 1 is only that:

[0053] The neutral rust remover is a commercially available SGR0203 neutral rust remover, brand: Xingrui.

[0054] Performance Test

[0055] The rusted carbon steel plates were divided into two groups. The first group used the neutral rust remover of Example 1, and the other group used the neutral rust remover of Comparative Example 1. Each group of samples was marked for easy identification.

[0056] The two groups of samples to be tested were immersed in the neutral rust remover stock solutions of Example 1 and Comparative Example 1, respectively, and ultrasonicated at 45° C. for 10 min, then rinsed with clean water, and finally treated with a universal water-based rust inhibitor for rust prevention.

[0057] Start timing from the time the rust remover is applied, and observe the rust removal every 2 minutes. The rust removal speed and results are shown in Table 1 and Figures 1-2 .

[0058] Table 1 Rust removal of carbon steel plate by neutral rust remover in Example 1 and Comparative Example 1

[0059] Rust removal time (minutes) Example 1 10 Comparative Example 1 26

[0060] It can be seen from Table 1 that, compared with Comparative Example 1, the neutral rust remover obtained in Example 1 of the present invention has a fast rust removal speed, thorough rust removal, a uniform workpiece surface, and will not rust back immediately after rust removal. Subsequent water washing and rust prevention only need to be carried out according to the time rhythm of the normal cleaning process.

[0061] Compare Figure 1 and Figure 2 It can be seen that the surface of the steel plate treated with the rust remover of the present invention is more uniform and presents a luster that is closer to the original color of the metal; in addition, while removing rust, the rust remover of the present invention has an extremely low degree of corrosion on the steel plate substrate, maintaining a good metallic texture, while the commercially available rust removers still have some rust spots after rust removal, and there is a difference between the rust removal and the original color of the metal. Therefore, the neutral rust remover prepared by the present invention has a better rust removal effect.

[0062] It can be seen from the above embodiments that the present invention provides a neutral rust remover and its preparation method and application. Through the compatibility of the raw materials, the obtained neutral rust remover has a fast rust removal speed, a thorough rust removal effect, and does not damage the surface color of the workpiece, thereby solving the technical problem of the present application.

[0063] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A neutral rust remover, characterized in that: Calculated by mass percentage, it includes the following components: Penetrant 0.1-2%, nonionic surfactant 0.1-1%, fluorine compound 0.1-10%, chlorine compound 0.1-2%, amine compound 0.5-15%, 2-acrylamide-2-methylpropane sulfonic acid 0.1-2%, hydrolyzed polymaleic anhydride 0.1-2%, carboxylate-sulfonate-nonionic terpolymer 0.1-2%, ammonium citrate 5-20%, oxalic acid 0.1-1%, water 50-80%.

2. The neutral rust remover according to claim 1, characterized in that: The penetrant includes JFC-4.

3. The neutral rust remover according to claim 1, characterized in that: The nonionic surfactant includes fatty alcohol polyoxyethylene ether-9.

4. The neutral rust remover according to claim 1, characterized in that: The fluorine compound includes ammonium bifluoride.

5. The neutral rust remover according to claim 1, characterized in that: The chlorine compound includes calcium chloride, sodium chloride, potassium chloride, magnesium chloride or ammonium chloride.

6. The neutral rust remover according to claim 1, characterized in that: The amine compound includes triethanolamine, diglycolamine, monoisopropanolamine or triisopropanolamine.

7. The method for preparing the neutral rust remover according to any one of claims 1 to 6, characterized in that: The following steps are involved: Under stirring conditions, a penetrant, a nonionic surfactant, a fluorine compound, a chlorine compound, an amine compound, 2-acrylamide-2-methylpropane sulfonic acid, hydrolyzed polymaleic anhydride, a carboxylate-sulfonate-nonionic terpolymer, ammonium citrate, oxalic acid and water are mixed to obtain a mixture; The mixture is mixed with an amine compound, and the pH value is adjusted to 6.0-6.5 to obtain a neutral rust remover.

8. The preparation method according to claim 7, characterized in that: The stirring speed is 30-60 r / min and the stirring time is 60-80 min.

9. Use of the neutral rust remover according to any one of claims 1 to 6 or the neutral rust remover prepared by the preparation method according to any one of claims 7 to 8 in the field of rust removal of carbon steel and cast iron.

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