Copper alloy organic acid compound corrosion inhibition cleaning agent as well as preparation method and application thereof

Abstract

The invention discloses a copper alloy organic acid compound corrosion inhibition cleaning agent as well as a preparation method and application thereof. Each liter of the copper alloy organic acid compound corrosion inhibition cleaning agent comprises the following raw material components: 10-100g / L of citric acid, 20-50g / L of gluconic acid, 0.1-1g / L of polyaspartic acid, 0.05-0.2 g / L of ethylenediamine tetramethylenephosphonic acid and the balance of water. Citric acid and gluconic acid are compounded to form a copper alloy cleaning agent, polyaspartic acid and ethylenediamine tetramethylenephosphonic acid are added to form a specific corrosion inhibition cleaning agent, and the copper alloy cleaning agent has a high cleaning effect on copper alloy, can achieve a corrosion inhibition synergistic effect, is non-toxic and environmentally friendly, and is a copper alloy green corrosion inhibitor with development potential.

Description

Technical Field

[0001] The present invention relates to an organic acid compound corrosion inhibitor cleaning agent, in particular to a copper alloy organic acid compound corrosion inhibitor cleaning agent, and also relates to a preparation method and application of the above organic acid compound corrosion inhibitor cleaning agent. Background Art

[0002] Copper alloy cleaning agents are chemical agents specifically used to remove surface contaminants (such as oxide layers, oil stains, carbon deposits, water scales, etc.) on copper and its alloys (such as brass, bronze, cupronickel, etc.), and at the same time need to have the functions of inhibiting metal corrosion and protecting the matrix material. Their objects of action include, but are not limited to: electronic components (such as circuit board connectors); copper tubes of heat exchangers; precision mechanical parts; copper alloy artifacts in cultural relic restoration, etc.

[0003] The core functions of copper alloy cleaning agents are to remove surface contaminants such as oxide layers, grease / carbon deposits and water scales; inhibit corrosion by adding corrosion inhibitors (such as polyaspartic acid) to form a protective film during the cleaning process to prevent excessive erosion of the copper matrix by acidic or alkaline cleaning solutions; environmental protection and safety, avoiding the use of strong acids (hydrochloric acid, nitric acid) or phosphorus / heavy metal components, reducing the discharge of toxic waste liquids, and conforming to the green trend of industrial cleaning; maintaining surface integrity, the surface of the copper alloy after cleaning should remain smooth, without pitting, intergranular corrosion and other damages, ensuring the reliability of subsequent processes such as electroplating and welding.

[0004] Existing copper alloy cleaning agents mostly use strong acids (such as hydrochloric acid, nitric acid) or phosphorus-containing corrosion inhibitors, which have problems such as strong corrosiveness, large environmental pollution, and high wastewater treatment costs. As a weak organic acid, citric acid has a weak corrosion inhibition ability for copper alloys when used alone, which will cause excessive corrosion or loss of luster on the surface, and will also affect the strength of the material. Therefore, a compounding method is needed to reduce the cleaning damage to copper alloys. Summary of the Invention

[0005] Object of the Invention: The object of the present invention is to provide a highly efficient, environmentally friendly and low-corrosion copper alloy organic acid compound corrosion inhibitor cleaning agent, and also provide a preparation method and application of the above copper alloy organic acid compound corrosion inhibitor cleaning agent.

[0006] Technical Solution: The copper alloy organic acid compound corrosion inhibitor cleaning agent of the present invention comprises the following components of raw materials per liter: 10-100 g / L of citric acid, 20-50 g / L of gluconic acid, 0.1-1 g / L of polyaspartic acid, 0.05-0.2 g / L of ethylenediaminetetramethylenephosphonic acid, and the balance is water.

[0007] Among them, the pH value of the corrosion inhibitor cleaning agent is 4-5.

[0008] Among them, the water is deionized water, and the compound corrosion inhibitor cleaning agent is of analytical purity.

[0009] The preparation method of the above-mentioned copper alloy organic acid compound corrosion inhibitor cleaning agent includes the following steps:

[0010] (1) Take 20-50% of the volume of water for preparing the target corrosion inhibitor cleaning agent;

[0011] (2) Take citric acid, gluconic acid, polyaspartic acid and ethylenediaminetetramethylenephosphonic acid, and dissolve them respectively with water to obtain citric acid cleaning solution, gluconic acid cleaning solution, polyaspartic acid corrosion inhibitor solution and ethylenediaminetetramethylenephosphonic acid corrosion inhibitor solution;

[0012] (3) Mix the above-mentioned citric acid cleaning solution, gluconic acid cleaning solution, polyaspartic acid corrosion inhibitor solution and ethylenediaminetetramethylenephosphonic acid corrosion inhibitor solution, stir until completely mixed, then add the remaining water to make up the volume, and stir evenly to obtain the copper alloy organic acid compound corrosion inhibitor cleaning agent.

[0013] Among them, in step (2), the concentration of the citric acid cleaning solution is 1-10%, and the concentration of the gluconic acid cleaning solution is 2-5%.

[0014] Among them, in step (3), the concentration ratio of the cleaning solution to the corrosion inhibitor is 1:2-2.5.

[0015] The present invention also discloses the application of the above-mentioned copper alloy organic acid compound corrosion inhibitor cleaning agent in the anti-corrosion of copper alloy in an acidic environment.

[0016] Among them, the application is to prepare a copper alloy compound cleaning agent, and then add a compound corrosion inhibitor for cleaning. The main components of the copper alloy are 99.90% Cu, 0.05% P, 0.05% Fe, 0.002% O, 0.002% Sb, etc., and the pH value of the acidic environment is 3-5.

[0017] Among them, during the application process, use on-site exploration instruments to monitor the corrosion of the compound cleaning solution after adding the corrosion inhibitor, and determine the protection effect of the corrosion inhibitor.

[0018] Invention principle: The copper alloy organic acid compound corrosion inhibitor cleaning agent of the present invention uses the compound of citric acid and gluconic acid as the cleaning agent, and combines polyaspartic acid and ethylenediaminetetramethylenephosphonic acid as the corrosion inhibitor to comprehensively improve the chelation efficiency and reduce the risk of acidic corrosion at the same time.

[0019] Among them, citric acid contains three carboxyl groups (-COOH), and forms a stable five-membered ring chelate (such as [Cu(C6H5O7)2] 2+ ) with Cu, and quickly dissolves copper oxide (CuO). Gluconic acid contains a polyhydroxy structure (-OH), coordinates with Cu through the hydroxyl oxygen atom 4- to assist in dissolving alkaline water scale (such as CuCO3), and prevent Cu 2+ from 2+Redeposition. The compounding of citric acid and gluconic acid produces a synergistic effect: CuO + citric acid + gluconic acid → Cu-citrate complex + Cu-gluconate complex + H2O. The two complexes are highly water-soluble, significantly enhancing the dirt stripping speed. Citric acid provides an acidic environment (pH ≈ 3 - 4) to promote the dissolution of the oxide layer, and gluconic acid, as a weak acid (pH ≈ 5 - 6), buffers the pH fluctuation of the system to avoid matrix corrosion caused by local over-acidity. The hydroxyl groups of gluconic acid can form an adsorption film on the copper surface and synergistically enhance the protection with corrosion inhibitors (such as PASP). After compounding, the corrosion rate can be reduced to <0.005 mm / a, which is better than the single acid system. Gluconic acid has mild chelating properties, with a pH close to neutral (5 - 7), and hardly corrodes the matrix. However, its cleaning speed is slow, the soaking time needs to be extended, and the cost is relatively high. The advantages of the cleaning agent compounding system are compared as follows:

[0020]

[0021]

[0022] Meanwhile, polyaspartic acid (PASP) is a biodegradable and highly efficient corrosion inhibitor, and polyaspartic acid has a wide range of uses. It can be found in water treatment, medicine, agriculture, daily chemicals and other fields. As a water treatment agent, its main functions are scale inhibition and / or dispersion, and it also has a corrosion inhibition effect. As a scale inhibitor, it is particularly suitable for inhibiting the formation of calcium carbonate scale, calcium sulfate scale, barium sulfate scale and calcium phosphate scale in cooling water, boiler water and reverse osmosis treatment. The scale inhibition rate for calcium carbonate can reach 100%. Polyaspartic acid also has a dispersion effect and can effectively prevent the corrosion of metal equipment. Ethylenediaminetetramethylenephosphonic acid (EDTMPS) belongs to nitrogen-containing organic polyphosphonic acid. Compared with inorganic polyphosphates, it is easier to adsorb on the surface of carbon steel. At the same time, EDTMPS ionizes into 8 ions in water and is easy to chelate with divalent metal ions, forming a three-dimensional structure viscous complex dispersed in water to prevent the formation of inorganic scale.

[0023] The compound corrosion inhibitor cleaning agent of the present invention combines citric acid + gluconic acid with polyaspartic acid + ethylenediaminetetramethylenephosphonic acid, and through the "chelating cleaning - adsorption corrosion inhibition" synergistic mechanism, it has excellent cleaning and corrosion inhibition effects on copper alloys. Its core advantage lies in the synergistic effect of multiple components: citric acid and gluconic acid efficiently dissolve copper oxides (CuO / Cu2O), and at the same time, the multi-hydroxyl structure of gluconic acid stabilizes copper ions and reduces secondary corrosion; polyaspartic acid (PASP) forms an adsorption protection film on the copper surface to inhibit the penetration of corrosive media; ethylenediaminetetramethylenephosphonic acid (EDTMP) captures free Cu through strong chelation 2+, prevent redeposition and enhance the compactness of the PASP film. This compound system not only significantly improves the oxidation layer removal efficiency (rapid cleaning at room temperature), but also can self-form a long-term corrosion inhibition film after cleaning, inhibit dezincification corrosion and maintain surface finish. At the same time, it has environmental friendliness (biodegradable components). Compared with traditional formulations (such as single citric acid + BTA), it has a breakthrough improvement in cleaning effect, corrosion inhibition persistence and material compatibility.

[0024] Therefore, the compound corrosion inhibition cleaning agent of the present invention realizes the unity of high efficiency and environmental friendliness in the cleaning of copper alloys, and is particularly suitable for fields with high requirements for surface integrity such as precision electronic components and heat exchangers. This formulation has significant industrial value in reducing corrosion risk and simplifying the wastewater treatment process.

[0025] Beneficial effects: Compared with the prior art, the present invention has the following remarkable advantages: (1) The organic acid compound corrosion inhibition cleaning agent for copper alloys of the present invention achieves a better corrosion inhibition effect through the compounding of citric acid, gluconic acid, polyaspartic acid and ethylenediaminetetramethylenephosphonic acid, effectively improving the corrosion inhibition performance. Compared with not adding a corrosion inhibitor, the corrosion inhibition efficiency is increased from about 54% to 90%. The surface integrity of the copper alloy after cleaning is high, and the low-phosphorus compounding scheme meets the requirements of green industry; (2) The preparation and use process of the organic acid compound corrosion inhibition cleaning agent for copper alloys of the present invention is simple, the production cost is low, the performance is stable and easy to store, which is convenient for storage and mass production, and has extremely high practical application value. Description of the Drawings

[0026] Figure 1 For the polarization curve (A) and impedance diagram (B) of copper alloy in the organic acid compound corrosion inhibition cleaning agent for copper alloys of the present invention in Example 1;

[0027] Figure 2 For the polarization curve of copper alloy in polyaspartic acid corrosion inhibitor;

[0028] Figure 3 For the impedance diagram of copper alloy in polyaspartic acid corrosion inhibitor;

[0029] Figure 4 For the polarization curve of copper alloy in ethylenediaminetetramethylenephosphonic acid corrosion inhibitor;

[0030] Figure 5 For the impedance diagram of copper alloy in ethylenediaminetetramethylenephosphonic acid corrosion inhibitor. Detailed Embodiments

[0031] The technical solution of the present invention will be further described below in conjunction with embodiments. The test materials used in the embodiments can be obtained through conventional channels.

[0032] Example 1

[0033] The copper alloy organic acid compound corrosion inhibitor cleaning agent of the present invention comprises raw materials of the following components: citric acid, gluconic acid, ethylenediaminetetramethylenephosphonic acid and water.

[0034] The preparation method of the above copper alloy organic acid compound corrosion inhibitor cleaning agent comprises the following steps:

[0035] (1) Take 20% of the volume of water for preparing the target cleaning agent.

[0036] (2) Weigh analytical pure citric acid, add water to prepare a 100 g / L citric acid cleaning solution with a volume of 50 ml.

[0037] Weigh analytical pure gluconic acid, add water to prepare a 30 g / L gluconic acid cleaning solution with a volume of 50 ml.

[0038] Weigh analytical pure polyaspartic acid, add water to prepare a 1 g / L polyaspartic acid corrosion inhibitor solution with a volume of 50 ml.

[0039] Weigh analytical pure ethylenediaminetetramethylenephosphonic acid, add water to prepare a 0.1 g / L ethylenediaminetetramethylenephosphonic acid corrosion inhibitor solution with a volume of 50 ml.

[0040] (4) Take the above four solutions, fully mix them and make up the volume to 1 L. Study the corrosion inhibition effect by adding polyaspartic acid and ethylenediaminetetramethylenephosphonic acid to the mixed solution of citric acid and gluconic acid, and verify the effect of the prepared copper alloy organic acid corrosion inhibitor cleaning agent of the present invention.

[0041] The usage method of the above corrosion inhibitor: The electrode material is copper alloy. Use a machine to process the copper alloy into a specimen with an outer dimension of 1 cm × 1 cm × 0.5 cm. The wire is welded to the back of the working surface of the specimen with tin solution, and the specimen is placed in it and sealed with epoxy resin; Subsequently, the working surface of the copper alloy is polished step by step with 400 - 2000# sandpaper until the surface is smooth. Clean the polished specimen with absolute ethanol and deionized water, degrease it with acetone, and dry it with cold air for standby.

[0042] Adopt a three - electrode system for measurement. The research electrode is copper alloy, the reference electrode is a saturated calomel electrode, and the auxiliary electrode is a platinum electrode. Immerse the research electrode in the polyaspartic acid and ethylenediaminetetramethylenephosphonic acid corrosion inhibitor cleaning agent, and form a three - electrode system with the saturated calomel electrode and the platinum electrode for electrochemical testing. When measuring the steady - state polarization curve, the scanning speed is 1 mV / s, and the scanning range is - 300 to 300 mV relative to the open - circuit potential. The electrode potential is relative to the saturated calomel electrode potential.

[0043] As Figure 1 shown, it is the polarization curve and impedance diagram of copper alloy in the copper alloy organic acid compound corrosion inhibitor cleaning agent of the present invention. The fitting parameters are shown in Table 1:

[0044] Table 1. Polarization curve and impedance diagram fitting parameters of copper alloy in organic acid compound corrosion inhibitor cleaning agent

[0045]

[0046] Polarization curves show that the corrosion potential of copper alloy in the PASP+EDTMPS solution exhibited a positive shift of 0.7 mV compared to the blank solution. The addition of PASP+EDTMPS significantly reduced the corrosion current density of the copper alloy, and the inhibition efficiency increased dramatically. The addition of PASP+EDTMPS enhanced the inhibitory effect on the copper alloy electrode reaction compared to using either PASP or EDTMPS alone.

[0047] From the impedance graph, it can be seen that the diameter of the semicircle increases with the addition of PASP+EDTMPS. After adding PASP+EDTMPS, the blank solution and 100g / L C6H8O7+30g / L C6H 12 The charge transfer resistance of O7+1g / L PASP+0.1g / L EDTMPS solution increased from 1.23×10 4 Increased to 2.21×10 5 Ω·cm 2 The addition of PASP+EDTMPS improves the inhibition efficiency to 94.43% in C6H8O7+C6H 12 The inhibition efficiency in the presence of O7 can be attributed to the synergistic effect of corrosion inhibition.

[0048] As can be seen from the above results, the combination of polyaspartic acid + ethylenediaminetetramethylenephosphonic acid with citric acid and gluconic acid as a corrosion inhibitor and cleaning agent for copper alloys can exert multiple synergistic effects: citric acid and gluconic acid can efficiently remove the oxides on the surface of copper alloys through acid dissolution and chelation. The carboxyl groups of polyaspartic acid can not only enhance the chelating ability towards copper ions, but also form a protective film on the metal surface after cleaning, significantly inhibiting corrosion; the combined action of the four components not only ensures the cleaning efficiency (especially for precision components and complex structures), but also reduces the erosion of the substrate through the pH buffering system. As a nitrogen-containing organic polyphosphonic acid, EDTMPS is more inclined to adhere to the surface of steel than inorganic polyphosphonic acids. In addition, EDTMPS dissociates into 8 ions in aqueous solution, promoting the chelation with divalent metal ions. This process forms a three-dimensional viscous complex dispersed in water, inhibiting the formation of inorganic scale. Therefore, EDTMPS is an effective inhibitor for corrosion and scale formation in oil wells. At the same time, the carboxyl groups of PASP and the phosphonic acid groups of EDTMPS are co-adsorbed to form a denser mixed protective film, covering the active sites (such as the anodic area) on the metal surface, inhibiting electrochemical corrosion. The chemical adsorption of EDTMPS fills the pores of the PASP physical film, forming an "organic phosphonate-polymer" composite film, significantly improving the denseness and adhesion of the film, and delaying the penetration of corrosive media. In addition, this compound system has both environmental friendliness (biodegradable, low toxicity) and process stability. In the cleaning of copper alloys in the fields of electronics, precision instruments, etc., it can not only completely remove the oxide layer, but also provide long-term corrosion inhibition protection, avoiding the problem of secondary corrosion.

[0049] Comparative Example 1

[0050] A polyaspartic acid corrosion inhibitor and cleaning agent comprises raw materials of the following components: citric acid, gluconic acid, polyaspartic acid and water.

[0051] The preparation method of the above polyaspartic acid corrosion inhibitor and cleaning agent comprises the following steps:

[0052] (1) Take 20% of the volume of water for preparing the target cleaning agent;

[0053] (2) Weigh analytical pure citric acid, add water, and prepare a 100 g / L citric acid cleaning solution with a volume of 50 ml;

[0054] Weigh analytical pure gluconic acid, add water, and prepare a 30 g / L gluconic acid cleaning solution with a volume of 50 ml;

[0055] Weigh analytical pure polyaspartic acid, add water, and respectively prepare 0.1, 0.5, 1 g / L polyaspartic acid corrosion inhibitor solutions with a volume of 50 ml;

[0056] (3) Take the above three solutions, fully mix them and make up the volume to 1 L, and mix the citric acid and gluconic acid to obtain the product.

[0057] Take the polyaspartic acid corrosion inhibitor cleaning agent prepared in Comparative Example 1 and perform the same application as in Example 1 to verify its effect; as Figure 2 shown, the polarization curves of copper alloy in polyaspartic acid corrosion inhibitor cleaning agents with different concentrations are presented. Through Tafel fitting, the obtained fitting parameters are shown in Table 2:

[0058] Table 2. Polarization curve fitting parameters of copper alloy in polyaspartic acid corrosion inhibitor cleaning agents with different concentrations

[0059]

[0060] Compared with that in the blank solution, in the solution containing PASP, the corrosion potential of the copper alloy shifted positively to a certain extent, but the positive shift amplitude was very small, less than 50 mV, and the corrosion current changed little with the increase of PASP concentration. At the same time, after adding PASP, the corrosion current density of the copper alloy decreased and the corrosion inhibition efficiency increased. After adding PASP, the inhibitory effect on the electrode reaction of the copper alloy was enhanced.

[0061] As Figure 3 shown, the impedance diagrams of copper alloy in polyaspartic acid corrosion inhibitor cleaning agents with different concentrations are presented. Through equivalent circuit fitting, the obtained fitting parameters are shown in Table 3:

[0062] Table 3. Impedance parameters of copper alloy in polyaspartic acid corrosion inhibitor cleaning agents with different concentrations

[0063]

[0064] From Figure 3 it can be seen that the diameter of the semicircle increases with the increase of the PASP addition amount. After adding 0.1 g / L PASP, the charge transfer resistance of the blank solution and the 10% C6H8O7 + 3% C6H 12 O7 + 0.1 g / L PASP solution increased from 1.23×10 4 [[ID=�2]]to 5.85×10 4 Ω·cm 2 , and then increased to 6.43×10 4 Ω·cm 2 after the addition amount of 0.5 g / L PASP. In addition, after adding 10% C6H8O7 + 3% C6H 12 O7 + 1 g / L PASP, the double-layer capacitance decreased from 2.17×10 -6 to 9.85×10 -7 F·cm -2 , and the inhibition efficiency increased from 78.97% to 87.12%, thus being related to the polarization results.

[0065] Compared with Example 1, the corrosion inhibition efficiency decreases significantly after adding PASP. The lack of EDTMP will significantly reduce the efficiency of the copper alloy corrosion inhibition cleaning agent. The main reason is that: as a strong multi-dentate chelating agent, EDTMP can efficiently complex dissolved Cu 2+ , preventing its re-deposition from causing secondary corrosion; at the same time, it forms a dense composite protective film synergistically with PASP, filling the gaps between the PASP molecular chains and enhancing the integrity of the corrosion inhibition barrier. If EDTMP is lacking, free Cu 2+ will accelerate galvanic corrosion, resulting in surface pitting or discoloration, and the inhibition effect on dezincification of brass will be weakened, ultimately causing a significant decline in the corrosion inhibition persistence and cleaning uniformity. Therefore, EDTMP is a key component for the long-term and stable protection of this compound system.

[0066] Comparative Example 2

[0067] An ethylene diamine tetramethylene phosphonic acid corrosion inhibition cleaning agent comprises raw materials of the following components: citric acid, gluconic acid, ethylene diamine tetramethylene phosphonic acid and water.

[0068] The preparation method of the above-mentioned ethylene diamine tetramethylene phosphonic acid corrosion inhibition cleaning agent comprises the following steps:

[0069] (1) Take 20% of the volume of water for preparing the target cleaning agent;

[0070] (2) Weigh analytical pure citric acid, add water, and prepare a 100 g / L citric acid cleaning solution with a volume of 50 ml;

[0071] Weigh analytical pure gluconic acid, add water, and prepare a 30 g / L gluconic acid cleaning solution with a volume of 50 ml;

[0072] Weigh analytical pure ethylene diamine tetramethylene phosphonic acid, add water, and respectively prepare 0.05, 0.1, 0.2 g / L ethylene diamine tetramethylene phosphonic acid with a volume of 50 ml;

[0073] (4) Take the above two solutions, fully mix them and make the volume up to 1 L, and mix citric acid and gluconic acid to obtain it.

[0074] Take the ethylene diamine tetramethylene phosphonic acid corrosion inhibition cleaning agent prepared in Comparative Example 2, and carry out the same application as in Example 1 to verify its effect; as Figure 4 shown, the polarization curves of copper alloy in ethylene diamine tetramethylene phosphonic acid corrosion inhibition cleaning agents with different concentrations are presented. Through Tafel fitting, the obtained fitting parameters are shown in Table 4:

[0075] Table 4. Polarization curve fitting parameters of copper alloy in ethylene diamine tetramethylene phosphonic acid corrosion inhibition cleaning agents with different concentrations

[0076] <id=

[0077] AsFigure 4 As shown, the addition of EDTMPS causes the polarization curve to shift towards lower current density. This indicates that once a protective film is formed on the surface of the copper alloy, EDTMPS can effectively inhibit the corrosion of the copper alloy in acidic solutions. The electrochemical parameters related to corrosion were determined using the Tafel extrapolation method. Compared with the blank solution, the maximum change in E corr remained below 85 mV. In addition, the anodic and cathodic curves decreased significantly, which is attributed to the action of EDTMPS, indicating that after adsorption onto the surface of the copper alloy, EDTMPS can simultaneously control the cathodic and anodic reactions of the electrode, and the inhibition efficiency reaches 79.32%.

[0078] As Figure 5 shown, the impedance diagrams of the copper alloy in corrosion inhibitor cleaning agents of ethylenediaminetetramethylenephosphonic acid at different concentrations are presented. Through equivalent circuit fitting, the obtained fitting parameters are shown in Table 5:

[0079] Table 5. Impedance parameters of copper alloy in corrosion inhibitor cleaning agents of ethylenediaminetetramethylenephosphonic acid at different concentrations

[0080]

[0081] Figure 5 The Nyquist diagrams of the copper alloy exposed to the acidic environment with and without EDTMPS are presented. After the introduction of EDTMPS, the radius shown in the figure gradually increases, but the radius at 0.2 g / L is slightly smaller than that at 0.1 g / L, indicating that the corrosion inhibition performance of EDTMPS on the copper alloy has two sides. When 10% C6H8O7 + 3% C6H 12 O7 + 0.1 g / L EDTMPS is added, the double-layer capacitance drops to 8.74×10 -7 F·cm -2 , and the inhibition efficiency drops from 79.60% to 72.90%, which is related to the polarization results.

[0082] Compared with Example 1, the lack of PASP will cause a significant decrease in the corrosion inhibition efficiency of the copper alloy corrosion inhibitor cleaning agent. The main reasons are as follows: As an environmentally friendly polymer corrosion inhibitor, the long-chain molecular structure of PASP can form a dense adsorption protective film on the surface of the copper alloy through carboxyl functional groups, effectively blocking the erosion of corrosive media; at the same time, the steric hindrance effect of its molecular chain can fill the microscopic defects on the metal surface and inhibit local corrosion. If PASP is lacking, the protective layer formed only by small molecule corrosion inhibitors (such as EDTMP) is not complete and durable enough to provide the same degree of physical barrier protection, resulting in easier penetration of corrosion factors and a significant reduction in the corrosion inhibition effect. In addition, the synergistic effect between PASP and EDTMP is damaged, and the structural integrity of the composite corrosion inhibition film is impaired, further weakening the overall protection ability of the system.

[0083] In order to verify that the copper alloy organic acid compound corrosion inhibitor cleaning agent prepared in Example 1 has the best corrosion inhibition effect, the appropriate concentration range is determined by the relationship between the corrosion inhibition efficiency and concentration of the corrosion inhibitor cleaning agent, and the concentration is used as the level and the type of cleaning agent as the factor. 16 (2 5 ) to conduct orthogonal experiments.

[0084] The orthogonal test is shown in Table 6:

[0085] Table 6, L9 (2 5 )Orthogonal factor level table

[0086]

[0087] The corrosion inhibition efficiency is calculated by using the polarization curves of the samples corresponding to the experimental numbers in the orthogonal experiment table shown in Table 6, as shown in Table 7.

[0088] Table 7. Analysis of orthogonal test results of the copper alloy organic acid composite corrosion inhibitor cleaning agent of the present invention

[0089]

[0090] Table 7 shows that the order of influence of factors A and B is A > B, meaning PASP is the primary influencing factor, followed by EDTMPS. The blank range (0.034) is smaller than the PASP range (0.042), but larger than the EDTMPS range (0.027), indicating a non-negligible interaction between the experimental factors. This demonstrates the feasibility of this orthogonal experiment. The mean values indicate that the organic acid compound corrosion inhibitor cleaning agent A3B2 of the present invention has the optimal concentration ratio.

[0091] Although the difference in corrosion inhibition efficiency between the embodiment of the present invention (94%) and the comparative example (87.12%, 79.60%) is numerically small, the technological breakthrough is significant: after the corrosion inhibition efficiency is close to 90%, every 1% increase requires overcoming the dual problems of synergistic effect and ratio optimization. The embodiment dissolves the oxide layer through a compound of citric acid and gluconic acid, combines the "adsorption-chelation" synergistic mechanism of PASP and EDTMPS, and forms a dense composite protective film to fill the defects of a single component (such as the pores of the PASP membrane or insufficient dispersibility of EDTMPS), thereby breaking through the efficiency bottleneck. The newly added orthogonal experimental comparative example proves that exceeding the ratio range of this application will lead to a sudden drop in performance and a decrease in corrosion inhibition performance, which contrasts with the scientific nature and criticality of the ratio of the present invention. In addition, the solution has both environmental protection and process compatibility, and achieves a balance between efficient corrosion inhibition, environmental protection and cost. The comprehensive technical advantages far exceed the comparative example, and the innovation is highly significant.

[0092] Therefore, the copper alloy organic acid compound corrosion inhibitor cleaning agent of the present invention uses a compound of citric acid and gluconic acid as a copper alloy cleaning agent, and forms a unique corrosion inhibitor cleaning agent by adding polyaspartic acid and ethylene diamine tetramethylene phosphonic acid. It not only has a high cleaning effect on copper alloys, but also can achieve a corrosion inhibition synergistic effect, and is non-toxic and environmentally friendly. It is a copper alloy green corrosion inhibitor with development potential.

Claims

1. A copper alloy organic acid compound corrosion inhibitor cleaning agent, characterized in that, The copper alloy organic acid compound corrosion inhibitor cleaning agent per liter comprises raw materials of the following components: 10 - 100 g / L of citric acid, 20 - 50 g / L of gluconic acid, 0.1 - 1 g / L of polyaspartic acid, 0.05 - 0.2 g / L of ethylenediaminetetramethylenephosphonic acid, and the balance is water.

2. The copper alloy organic acid compound corrosion inhibitor cleaning agent according to claim 1, characterized in that The pH value of the corrosion inhibitor cleaning agent is 4 - 5.

3. The copper alloy organic acid compound corrosion inhibitor cleaning agent according to claim 1, characterized in that The water is deionized water, and the compound corrosion inhibitor cleaning agent is of analytical purity.

4. A preparation method of the copper alloy organic acid compound corrosion inhibitor cleaning agent according to claim 1, characterized in that, It includes the following steps: (1) Take water with a volume of 20 - 50% of the target corrosion inhibitor cleaning agent to be prepared; (2) Take citric acid, gluconic acid, polyaspartic acid and ethylenediaminetetramethylenephosphonic acid, and dissolve them respectively with water to obtain a citric acid cleaning solution, a gluconic acid cleaning solution, a polyaspartic acid corrosion inhibitor solution and an ethylenediaminetetramethylenephosphonic acid corrosion inhibitor solution; (3) Mix the above citric acid cleaning solution, gluconic acid cleaning solution, polyaspartic acid corrosion inhibitor solution and ethylenediaminetetramethylenephosphonic acid corrosion inhibitor solution, stir until completely mixed, then make up the volume with the remaining water and stir evenly to obtain the copper alloy organic acid compound corrosion inhibitor cleaning agent.

5. The preparation method according to claim 4, characterized in that, In step (2), the concentration of the citric acid cleaning solution is 1 - 10%, and the concentration of the gluconic acid cleaning solution is 2 - 5%.

6. The preparation method according to claim 4, wherein In step (3), the concentration ratio of the cleaning solution to the corrosion inhibitor is 1:2 - 2.

5.

7. Application of the copper alloy organic acid compound corrosion inhibitor cleaning agent according to claim 1 in the anti-corrosion of copper alloy in an acidic environment.

8. The application according to claim 7, wherein The application is to place the copper alloy in the compound corrosion inhibitor cleaning agent for cleaning, and the pH value of the acidic environment is 3 - 5.

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