Copper corrosion inhibitor and preparation method thereof

Abstract

The invention relates to the technical field of copper corrosion inhibitors, in particular to a copper corrosion inhibitor which comprises the following components in parts by weight: 20-40 parts of aminobenzimidazole / Co < 2 + > MOFs, 30-50 parts of small molecular alcohol with the molecular weight not more than 60wt%, and 10-40 parts of a strong-polarity organic solvent with the polarity not weaker than that of hexamethylphosphoramide. According to the corrosion inhibitor, the metal organic framework material MOFs serves as a main component, corrosion of Cl <-> in a salt solution to copper can be effectively inhibited, and the corrosion inhibitor is small in dosage (the dosage of the corrosion inhibitor can be as low as 20 ppm), remarkable in corrosion inhibition effect and environmentally friendly. Moreover, the copper corrosion inhibitor can be used in different temperature environments (the temperature range can be 25-60 DEG C, and the copper corrosion inhibitor is free of volatility and toxicity), and the copper corrosion inhibitor can be directly added into a corrosive medium.

Description

Technical Field

[0001] The invention relates to the technical field of copper corrosion inhibitors, and in particular to a copper corrosion inhibitor and a preparation method of the corrosion inhibitor. Background Art

[0002] Copper is widely used as a structural material due to its excellent electrical and thermal conductivity and easy processing properties. However, copper is susceptible to corrosion during use, especially in solutions containing chloride ions, where it is very susceptible to pitting corrosion, which can lead to structural damage. Adding corrosion inhibitors to corrosive media is the most convenient, efficient and economical means to inhibit material corrosion, and is currently widely used in industry. However, there are few types of copper corrosion inhibitors, and most of them have low corrosion inhibition performance; and corrosion inhibitors with good corrosion inhibition performance for copper, such as benzotriazole, have certain toxicity. Therefore, the market is in urgent need of a copper corrosion inhibitor with superior corrosion inhibition performance and green environmental protection.

[0003] Metal-organic frameworks (MOFs) are a new type of crystalline porous materials, which are composed of metal ion clusters, metal oxide clusters and organic linkers to form a regular porous network. Since the 1990s, MOFs materials have created unprecedented opportunities for widespread application due to their supramolecular properties, large specific surface area, rich systems and heteroaromatic topological structures. Since MOFs materials have high boiling points and are non-volatile, they are non-toxic. In addition, MOFs have a stable structure and most of them are highly hydrophobic. Therefore, by preparing highly hydrophobic and structurally stable MOFs materials with adsorption groups for use as corrosion inhibitors, the market requirements for copper corrosion inhibitors can be met. Summary of the invention

[0004] The present invention aims at the deficiencies in the prior art and provides the following technical solutions:

[0005] According to one aspect of the present invention, a copper corrosion inhibitor is provided, comprising the following components by weight:

[0006] 20-40 parts by weight of aminobenzimidazole / Co 2+ MOFs, 30-50 parts by weight of a small molecule alcohol having a molecular weight not exceeding 60 wt%, and 10-40 parts by weight of a strongly polar organic solvent having a polarity not weaker than that of hexamethylphosphoramide, wherein the aminobenzimidazole / Co 2+ MOFs have the structural formula shown in the following formula (I):

[0007]

[0008] According to another aspect of the present invention, a method for preparing a copper corrosion inhibitor is also provided, comprising the following steps:

[0009] S10, using cobalt compound and 2-aminobenzimidazole as raw materials and N-N-dimethylformamide as reaction solvent to react and generate metal organic framework material MOFs as shown in formula (I), wherein the molar ratio of cobalt ions to 2-aminobenzimidazole in the raw materials satisfies 1:2-2.6, and the amount of the reaction solvent is 700-1000 mL;

[0010] S20, stirring and mixing the metal organic framework material MOFs obtained in step S10 with a small molecule alcohol and a strong polar organic solvent to obtain a copper corrosion inhibitor.

[0011] As an improvement of the above technical solution, in step S10, the reaction between the raw material and the reaction solvent is specifically a solvothermal reaction.

[0012] As an improvement of the above technical solution, the solvent thermal reaction includes two heating stages;

[0013] First, the reaction is carried out at 60-90°C for 0.5-2 hours;

[0014] Then, the temperature is continuously raised and the reaction is maintained at 120 to 160° C. for 18 to 36 hours.

[0015] As an improvement of the above technical solution, in step S10, the cobalt compound is selected from at least one of cobalt sulfate, cobalt carbonate, cobalt nitrate, and cobalt nitrate tetrahydrate;

[0016] The highly polar organic solvent is selected from at least one of NN dimethylformamide, formamide, NN dimethylacetamide and dimethyl sulfoxide.

[0017] As an improvement of the above technical solution, in step S20, the small molecule alcohol is selected from at least one of methanol, ethanol, and isopropanol.

[0018] Beneficial effects of the present invention:

[0019] With metal organic framework material MOFs as the main component, it can effectively inhibit the corrosion of copper by Cl- in salt solution, and the amount of the corrosion inhibitor is small (the amount of the corrosion inhibitor can be as low as 20ppm), the corrosion inhibition effect is significant, and it is green and environmentally friendly. In addition, the copper corrosion inhibitor can be used in different temperature environments (the temperature range can be 25-60℃, it is non-volatile and non-toxic), and the corrosion inhibitor can be directly added to the corrosive medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The present invention is a diagram of the corrosion inhibitor preparation process in a method for preparing a copper corrosion inhibitor. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] There are few types of existing copper corrosion inhibitors, and most of them have low corrosion inhibition performance; and corrosion inhibitors with better copper corrosion inhibition performance, such as benzotriazole, have certain toxicity. Therefore, the market is in urgent need of a copper corrosion inhibitor with superior corrosion inhibition performance and green environmental protection.

[0023] In order to solve the above technical problems, the following solutions are provided.

[0024] According to one aspect of the present invention, a copper corrosion inhibitor is provided, comprising the following components by weight:

[0025] 20-40 parts by weight of aminobenzimidazole / Co 2+ MOFs, 30-50 parts by weight of a small molecule alcohol having a molecular weight not exceeding 60 wt%, and 10-40 parts by weight of a strongly polar organic solvent having a polarity not weaker than that of hexamethylphosphoramide, wherein the aminobenzimidazole / Co 2+ MOFs have the structural formula shown in the following formula (I):

[0026]

[0027] This scheme adopts aminobenzimidazole / Co 2+ MOFs is the key main material for copper corrosion inhibitor, and aminobenzimidazole / Co 2+ The strong hydrophobicity and stable structure of MOFs adsorption groups can provide good corrosion inhibition for copper or copper alloy materials.

[0028] The aminobenzimidazole / Co 2+ MOFs together constitute copper corrosion inhibitors. Among them, small molecule alcohols have low viscosity and are miscible with most solvents, which can increase the content of aminobenzimidazole / Co 2+ The fluidity of MOFs solution; and the strong polar organic solvent has good solubility and can dissolve the synthesized MOFs solid; it is based on the synergistic cooperation between these components that the corresponding corrosion inhibitor as a whole can effectively play a corrosion inhibition role on copper element or copper alloy materials.

[0029] The setting of the mass ratio is determined through repeated experiments. First, the ratio of the reactant cobalt salt to aminobenzimidazole is obtained according to the orthogonal experimental results of different molar ratios. The amount of solvent in the synthesis reaction will affect the size of MOFs particles. The solvent addition ratio is different in various literatures. The proportion of the solvent is determined by experimental results based on the actual situation. Finally, the specific mass ratio of the present invention is determined. By setting the aminobenzimidazole / Co 2+ The mass ratio of MOFs, small molecule alcohols and strong polar organic solvents is controlled to be (20-40):(30-50):(10-40), which can not only dissolve the synthesized MOFs but also achieve the best corrosion inhibition effect.

[0030] The small molecule alcohol and strong polar organic solvent are combined with aminobenzimidazole / Co 2+ MOFs together constitute copper corrosion inhibitors. When obtaining this corrosion inhibitor, the selection of reactants, small molecule alcohols and strong polar organic solvents comprehensively considers non-toxicity, corrosion inhibition performance and economy. Through experiments, aminobenzimidazole was selected from various imidazoles, and cobalt salt was selected from various metal salts; in the selection of small molecule alcohols and strong polar solvents, the solubility, the effect on the reaction and other factors were taken into consideration, and the corresponding alcohols and strong polar organic solvents were screened out through experiments.

[0031] See attached Figure 1 According to another aspect of the present invention, a method for preparing a copper corrosion inhibitor is provided, comprising the following steps:

[0032] S10, using cobalt compound and 2-aminobenzimidazole as raw materials and N-N-dimethylformamide as reaction solvent to react and generate metal organic framework material MOFs as shown in formula (I), wherein the molar ratio of cobalt ions to 2-aminobenzimidazole in the raw materials satisfies 1:2-2.6, and the amount of the reaction solvent is 700-1000 mL;

[0033] S20, stirring and mixing the metal organic framework material MOFs obtained in step S10 with a small molecule alcohol and a strong polar organic solvent to obtain a copper corrosion inhibitor.

[0034] Different molar ratios not only affect the success or failure of MOFs synthesis, but also their particle size. The optimal synthesis ratio was determined by setting up several groups of reaction experiments with different molar ratios. In addition, in terms of experimental conditions, for central metal ions with flexible and diverse coordination modes and organic ligands with multiple coordination sites, changing the conditions can easily form supramolecular isomers.

[0035] The present invention uses cobalt compounds and 2-aminobenzimidazole as raw materials and N-N-dimethylformamide as solvent for a solvent thermal reaction, and preferably controls the solvent thermal reaction to firstly react at 60-90° C. for 0.5-2 hours and then react at 120-160° C. for 18-36 hours, thereby generating a metal organic framework material MOFs as shown in formula (I).

[0036] On the one hand, the temperature rise should be stable and uniform; on the other hand, the heating should be divided into two stages. Controlling the temperature and time of each stage can make MOFs be successfully synthesized. In the first stage, the reaction is kept at 60-90℃ for 0.5-2 hours to allow the two reactants to react fully. In the second stage, the temperature is continued to rise to 120-160℃ for 18-36 hours, which can provide temperature conditions for MOF growth. In this way, the overall reaction can provide a suitable temperature condition for MOFs growth. Therefore, through a large number of experimental explorations, the stage of programmed temperature rise was finally determined.

[0037] The reaction during the preparation of the corrosion inhibitor is as follows Figure 1 shown.

[0038] To facilitate understanding of the preparation method proposed in the present invention, the following examples will be used to further illustrate. It should be noted that the cobalt compound is selected from at least one of cobalt sulfate, cobalt carbonate, cobalt nitrate, and cobalt nitrate tetrahydrate; the strong polar organic solvent is selected from at least one of N—N dimethylformamide, formamide, N—N dimethylacetamide, and dimethyl sulfoxide. The small molecule alcohol is selected from at least one of methanol, ethanol, and isopropanol.

[0039] Embodiment 1

[0040] Put 56g of cobalt nitrate, 50g of 2-aminobenzimidazole and 800mL of N,N-dimethylformamide into a beaker and stir to dissolve. After mixing evenly, transfer to a closed hydrothermal kettle for heating solvent thermal reaction. When the reaction temperature reaches 80°C, maintain the temperature for 1 hour; continue to heat to 140°C and maintain the temperature for 24 hours to obtain aminobenzimidazole / Co. 2+ MOFs. Add 20 g of the aminobenzimidazole / Co prepared above into a beaker. 2+ MOFs, 40 g of isopropanol, and 40 g of N,N-dimethylformamide to obtain 100 g of copper corrosion inhibitor.

[0041] Corrosion inhibition performance evaluation:

[0042] The corrosion inhibition performance of the copper corrosion inhibitor of the present invention on red copper was evaluated by the weight loss hanging film method at 25° C. and 0.5 M NaCl solution, and the weight loss hanging film time was 72 hours.

[0043] The following table shows the comparative evaluation results of the corrosion inhibitor in this example and commercially available methylbenzotriazole:

[0044]

[0045] It can be seen from the data in the table that in the evaluation system, the corrosion inhibitor of the present invention has a significant inhibitory effect on the corrosion of copper, and the corrosion inhibition performance is also better than that of the commercially available methylbenzotriazole product.

[0046] Embodiment 2

[0047] Put 50g of cobalt sulfate, 100g of 2-aminobenzimidazole and 700mL of N,N-dimethylformamide into a beaker and stir to dissolve. After mixing evenly, transfer to a closed hydrothermal kettle for heating solvent thermal reaction. When the reaction temperature reaches 60°C, maintain the temperature for 0.5 hours; continue to heat to 120°C and maintain the temperature for 18 hours to obtain aminobenzimidazole / Co 2+ MOFs.

[0048] Add 40 g of the aminobenzimidazole / Co prepared above into a beaker. 2+ MOFs, 30 g methanol, 30 g formamide, and 100 g copper corrosion inhibitor was obtained.

[0049] Corrosion inhibition performance evaluation:

[0050] The corrosion inhibition performance of the copper corrosion inhibitor of the present invention on red copper was evaluated by the weight loss hanging film method at 50° C. and 0.3 M NaCl solution, and the weight loss hanging film time was 72 hours.

[0051] The following table shows the comparative evaluation results of the corrosion inhibitor in this example and commercially available benzotriazole:

[0052]

[0053]

[0054] It can be seen from the test data in the table that in the evaluation system, the corrosion inhibitor of the present invention has a significant corrosion inhibition effect on red copper, and the corrosion inhibition performance is also better than that of commercially available benzotriazole products.

[0055] Embodiment 3

[0056] Put 56g of cobalt nitrate, 65g of 2-aminobenzimidazole and 1000mL of N,N-dimethylformamide into a beaker and stir to dissolve. After mixing evenly, transfer to a closed hydrothermal kettle for heating solvent thermal reaction. When the reaction temperature reaches 90°C, maintain the temperature for 2 hours; continue to heat to 160°C and maintain the temperature for 36 hours to obtain aminobenzimidazole / Co. 2+ MOFs.

[0057] Add 30 g of the aminobenzimidazole / Co prepared above into a beaker. 2+ MOFs, 40 g ethanol, and 30 g formamide to obtain 100 g copper corrosion inhibitor.

[0058] Corrosion inhibition performance evaluation:

[0059] The corrosion inhibition performance of the copper corrosion inhibitor of the present invention on red copper was evaluated by the weight loss hanging film method at 60° C. and 0.2 M NaCl solution, and the weight loss hanging film time was 72 hours.

[0060] The following table shows the comparative evaluation results of the corrosion inhibitor in this example and commercially available mercaptobenzothiazole:

[0061]

[0062] It can be seen from the test data in the table that in the evaluation system, the corrosion inhibitor of the present invention has a significant corrosion inhibition effect on red copper, and the corrosion inhibition performance is also better than that of commercially available mercaptobenzothiazole products.

[0063] In addition to N,N-dimethylformamide and N,N-dimethylacetamide used in the solvent thermal reaction in the above embodiments, dimethyl sulfoxide can also be used as a solvent as long as it can dissolve the reactants, has a high boiling point, does not decompose within a given range, and does not participate in the reaction.

[0064] The copper corrosion inhibitor of the present invention, in addition to aminobenzimidazole / Co 2+ In addition to MOFs, small molecule alcohols, and highly polar organic solvents, other functional ingredients can be added according to actual needs, such as surfactants with solubilizing and dispersing effects, scale inhibitors that inhibit metal scaling, and bactericides with bactericidal effects.

[0065] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

[0066] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them.

Claims

1. A copper corrosion inhibitor, characterized in that The following components are included by weight: 20-40 parts by weight of aminobenzimidazole / Co 2+ MOFs, 30-50 parts by weight of a small molecule alcohol having a molecular weight not exceeding 60 wt%, and 10-40 parts by weight of a strongly polar organic solvent having a polarity not weaker than that of hexamethylphosphoramide, wherein the aminobenzimidazole / Co 2+ MOFs have the structural formula shown in the following formula (I):

2. A method for preparing a copper corrosion inhibitor, used for preparing the copper corrosion inhibitor according to claim 1, characterized in that: The following steps are involved: S10, using cobalt compound and 2-aminobenzimidazole as raw materials and N-N-dimethylformamide as reaction solvent to react and generate metal organic framework material MOFs as shown in formula (I), wherein the molar ratio of cobalt ions to 2-aminobenzimidazole in the raw materials satisfies 1:2-2.6, and the amount of the reaction solvent is 700-1000 mL; S20, stirring and mixing the metal organic framework material MOFs obtained in step S10 with a small molecule alcohol and a strong polar organic solvent to obtain a copper corrosion inhibitor.

3. The method for preparing a copper corrosion inhibitor according to claim 2, characterized in that: In step S10, the reaction between the raw material and the reaction solvent is specifically a solvothermal reaction.

4. The method for preparing a copper corrosion inhibitor according to claim 3, characterized in that: The solvothermal reaction includes two heating stages; First, the reaction is carried out at 60-90°C for 0.5-2 hours; Then, the temperature is continuously raised and the reaction is maintained at 120 to 160° C. for 18 to 36 hours.

5. The method for preparing a copper corrosion inhibitor according to claim 2, characterized in that: In step S10, the cobalt compound is selected from at least one of cobalt sulfate, cobalt carbonate, cobalt nitrate, and cobalt nitrate tetrahydrate; The highly polar organic solvent is selected from at least one of NN dimethylformamide, formamide, NN dimethylacetamide and dimethyl sulfoxide.

6. A method for preparing a copper corrosion inhibitor according to any one of claims 2 to 5, characterized in that: In step S20, the small molecule alcohol is selected from at least one of methanol, ethanol and isopropanol.

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