Environment-friendly electroplating solution for nickel coating

Abstract

The invention discloses an environment-friendly electroplating solution for a nickel coating. The environment-friendly electroplating solution for the nickel coating comprises the following components in parts by weight: 100 parts of nickel aminosulfonate, 7.9 to 13.2 parts of nickel methanesulfonate, 9.2 to 11.8 parts of boric acid, 0.026 to 0.079 part of a sulfur-free stress relieving agent, 0.0026 to 0.013 part of a leveling agent, 0.013 to 0.053 part of a brightening agent, 0.13 to 0.53 part of a wetting agent and 260 to 270 parts of deionized water. The sulfur-free stress relieving agent is a mixture of one or more of coumarin and derivatives thereof; the leveling agent adopts a polyethyleneimine derivative; and the brightener adopts an alkynol-ethylene oxide addition product. According to the environment-friendly electroplating solution for the nickel coating, a sulfur-containing primary brightener is completely abandoned, coumarin is adopted as a stress relieving agent, a sulfur-free semi-bright nickel layer can be obtained, when the environment-friendly electroplating solution is combined with micropore / microcrack chromium, the corrosion penetration speed can be greatly delayed, the corrosion resistance of the whole coating is remarkably improved, and meanwhile, the corrosion resistance of the whole coating is improved. Sulfur-containing organic matters are prevented from entering the wastewater from the source, and the wastewater treatment process is simplified.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electroplating solution, in particular to an environmentally-friendly electroplating solution for nickel plating. BACKGROUND

[0002] As a surface treatment technology widely used in decorative plating and functional plating, nickel electroplating plays an important role in the automotive, electronic, hardware and bathroom industries. The plating layer has good mechanical properties, corrosion resistance and aesthetics. Currently, the widely used nickel plating solution system in industry is developed on the basis of Watts nickel, which mainly includes main salt (such as nickel sulfate, nickel chloride) to provide nickel ions, boric acid as a buffer, and various additives (such as brightener, leveling agent, wetting agent, etc.).

[0003] However, with the increasing strictness of global environmental regulations and the deepening of the concept of sustainable development, the traditional nickel plating technology exposes many environmental and performance problems that need to be solved, which are specifically manifested in the following aspects: the traditional nickel plating solution relies heavily on organic additives to obtain bright and smooth plating. Among them, the primary brightener is a sulfur-containing compound, which can reduce the tensile stress of the plating layer, but will introduce sulfur elements into the plating layer. The chemical activity of sulfur-containing nickel plating layer is higher, and as a bottom layer, it will accelerate the penetration of corrosive media vertically, significantly reducing the overall corrosion resistance of the multi-layer nickel-chromium system. Secondary brighteners such as etherification products of butyne diol, pyridine, and quinoline derivatives often have high biological toxicity, unpleasant odor, and are not easily biodegradable.

[0004] Therefore, there is an urgent need in the art for a completely new and systematic nickel plating solution formula that can eliminate or significantly reduce the use of harmful substances at the source, while ensuring and even improving the overall performance of the plating layer, and has good process stability and operability to meet the dual requirements of environmental protection and quality for modern industry. SUMMARY

[0005] Therefore, there is an urgent need in the art for a completely new and systematic nickel plating solution formula that can eliminate or significantly reduce the use of harmful substances at the source, while ensuring and even improving the overall performance of the plating layer, and has good process stability and operability to meet the dual requirements of environmental protection and quality for modern industry.

[0006] An environmentally-friendly electroplating solution for nickel plating, which includes the following components by weight fraction: 100 parts of nickel sulfamate, 7.9-13.2 parts of nickel methylsulfonate, 9.2-11.8 parts of boric acid, 0.026-0.079 parts of sulfur-free stress reliever, 0.0026-0.013 parts of leveling agent, 0.013-0.053 parts of brightener, 0.13-0.53 parts of wetting agent, and 260-270 parts of deionized water.

[0007] The sulfur-free stress reliever is a mixture of one or more of coumarin and its derivatives.

[0008] The leveling agent is a polyethyleneimine derivative.

[0009] The brightener is an acetylenic alcohol-oxirane adduct.

[0010] In one embodiment, the wetting agent is one of perfluoropolyether ether and alkyl polyglucoside.

[0011] In one embodiment, the pH value of the nickel plating environmentally-friendly plating solution is set to 3.8-4.5.

[0012] In one embodiment, the pH value of the nickel plating environmentally-friendly plating solution is adjusted by one or a mixture of both of methanesulfonic acid and sulfamic acid.

[0013] In one embodiment, the nickel plating environmentally-friendly plating solution includes the following components by weight fraction: 100 parts of nickel sulfamate, 7.9-10.5 parts of nickel methanesulfonate, 9.2-10.5 parts of boric acid, 0.026-0.039 parts of sulfur-free stress reliever, 0.0026-0.0079 parts of leveling agent, 0.013-0.026 parts of brightener, 0.13-0.26 parts of wetting agent, and 260-263 parts of deionized water.

[0014] In one embodiment, the nickel plating environmentally-friendly plating solution includes the following components by weight fraction: 100 parts of nickel sulfamate, 10.5-13.2 parts of nickel methanesulfonate, 10.5-11.8 parts of boric acid, 0.039-0.079 parts of sulfur-free stress reliever, 0.0079-0.013 parts of leveling agent, 0.026-0.053 parts of brightener, 0.26-0.53 parts of wetting agent, and 263-270 parts of deionized water.

[0015] In one embodiment, the nickel plating environmentally-friendly plating solution includes the following components by weight fraction: 100 parts of nickel sulfamate, 7.9 parts of nickel methanesulfonate, 9.2 parts of boric acid, 0.026 parts of coumarin, 0.0026 parts of PEI derivative (50% aqueous solution), 0.013 parts of acetylenic alcohol-oxirane adduct, 0.13 parts of PFPE (50% aqueous solution), and 260 parts of deionized water.

[0016] In one embodiment, the nickel plating bath includes the following components by weight fraction: 100 parts of nickel sulfamate, 10.5 parts of nickel methylsulfonate, 10.5 parts of boric acid, 0.039 parts of coumarin, 0.0079 parts of PEI derivative (50% aqueous solution), 0.026 parts of alkyne alcohol-ethylene oxide adduct, 0.26 parts of PFPE (50% aqueous solution), and 263 parts of deionized water.

[0017] In one embodiment, the nickel plating bath includes the following components by weight fraction: 100 parts of nickel sulfamate, 13.2 parts of nickel methylsulfonate, 11.8 parts of boric acid, 0.079 parts of coumarin, 0.013 parts of PEI derivative (50% aqueous solution), 0.053 parts of alkyne alcohol-ethylene oxide adduct, 0.53 parts of PFPE (50% aqueous solution), and 270 parts of deionized water.

[0018] In one embodiment, the operating temperature of the nickel plating bath is set to 50-60°C.

[0019] In one embodiment, the cathode current density of the nickel plating bath in practical application is limited to 2-8 A / dm2.

[0020] In one embodiment, the cathode current density of the nickel plating bath in practical application is limited to 3-5 A / dm2.

[0021] In one embodiment, the stirring method of the nickel plating bath in practical application is one of gentle air stirring or cathode movement, to ensure uniform distribution of additives and prevent concentration polarization.

[0022] In one embodiment, the nickel plating bath is prepared by the following steps: A1. Dissolve nickel sulfamate and nickel methylsulfonate in 1 / 2 volume of deionized water in the main tank under heating and stirring; A2. Completely dissolve boric acid in hot water (>60°C) in another container, then pour into the main tank; A3. Add water to the main tank to approach the volume, and stir uniformly; A4. Adjust the pH to 3.8-4.5 with methylsulfonic acid; A5. Add the measured coumarin (which can be first dissolved with a small amount of ethanol), PEI derivative, alkyne alcohol-ethylene oxide adduct, and wetting agent, and stir thoroughly after each addition; A6. Add water to the final volume, and stir uniformly; A7, Small current electrolysis (0.2-0.5 A / dm2, 4-6 hours) treatment to remove heavy metal impurities, and then test plating.

[0023] In one embodiment, the above-mentioned nickel plating environmentally friendly electroplating solution is prepared by the following steps: B1, Take a 200 mL beaker, add about 100 mL of deionized water, heat to 60-70°C; Under stirring, slowly add 40.0 grams of boric acid, stir until completely clear and transparent; Place in a water bath for preservation, prevent cooling crystallization; B2, In a small beaker, dissolve 0.15 grams of coumarin in about 20-30 milliliters of anhydrous ethanol; Stir until completely dissolved to obtain a clear solution; This is A liquid, sealed for use; B3, Add about 500 milliliters of deionized water to a 1.5 liter main preparation container, start stirring and heat to 50-55°C; B4, Under strong stirring, slowly add 380 grams of nickel sulfamate and 40 grams of nickel methyl sulfonate in batches; B5, Continue stirring for about 30 minutes until all solids are completely dissolved to obtain a dark green clear solution; B6, Slowly pour the previously prepared and preserved hot aqueous boric acid solution into the main preparation container under stirring; B7, Rinse the beaker containing boric acid with a small amount of deionized water, pour the wash into the main tank to ensure no loss; B8, Continue stirring for 10 minutes to ensure uniform mixing of the solution; B9, Add deionized water to the container to bring the total volume close to 950 milliliters (leave space for adding additives); B10, Stabilize the solution temperature at 55°C; B11, After calibrating the pH meter, insert it into the solution, slowly add methyl sulfonic acid under slow stirring to accurately adjust the pH value to 4.2; The addition process should be slow and the pH value should be read constantly to prevent over-acidification; B12, Add stress reliever: slowly add all the pre-dissolved A liquid (coumarin ethanol solution) into the main solution under stirring; B13, Add high molecular leveling agent: accurately pipette 0.03 mL of PEI derivative; Due to its viscosity, it should be slowly added to the center of the vortex formed by stirring to allow it to disperse quickly and prevent local condensation; Continue stirring for 15 minutes; B14, Add secondary brightener: accurately pipette 0.1 mL of alkyne alcohol-oxirane adduct and add under stirring; Continue stirring for 10 minutes; B15. Add wetting agent: pipette 1.0 mL of PFPE solution and add to the solution under stirring; continue stirring for 15-20 minutes to ensure complete mixing of all additives; B16. Final volume: accurately make up the solution to 1 liter with deionized water; stir for another 30 minutes; B17. Pour the prepared plating solution into the electrolytic cell; B18. Hang the clean corrugated cathode plate and anode into the cell; B19. Start air agitation at a temperature of 50-55°C and apply a low current density of 0.2-0.5 A / dm2; B20. Electrolytic treatment for 4-6 hours, or until the deposited coating on the cathode plate is uniform, dense, and free of dark or gray stripes; this step effectively removes heavy metal impurities from the solution.

[0024] The above-mentioned environmentally friendly nickel plating solution completely abandons the sulfur-containing primary brightener, and uses coumarin as a stress reliever. The sulfur in the traditional nickel plating layer reduces its corrosion resistance, and when combined with a subsequent chromium layer to form a multi-layer system, it acts as an active anode to accelerate the longitudinal corrosion of the underlying nickel layer. The sulfur-free semi-bright nickel layer obtained by the present solution, when combined with a microporous / microcracked chromium layer, can significantly delay the corrosion penetration rate and significantly improve the corrosion resistance of the overall coating. At the same time, the use of sulfur-containing organic compounds in wastewater is avoided from the source, simplifying the wastewater treatment process. Specifically, the present solution uses a low-toxicity acetylenic alcohol-ethylene oxide adduct to replace traditional pyridine and quinoline derivatives; biodegradable APG or extremely stable and low-use PFPE is used to replace sodium dodecyl sulfate. As a result, the selection of new additives is based on their low biological toxicity and high biodegradability, which significantly reduces the potential harm of electroplating waste and cleaning wastewater to the environment, avoids the foul odor of pyridine compounds, and creates a safer and healthier workshop environment, meeting the requirements of modern green manufacturing. The new wetting agent has little or no foam, reducing material loss and environmental pollution caused by foam overflow; using nickel sulfamate as the main salt, supplemented by a small amount of nickel methylsulfate, avoids high concentrations of sulfate and chloride ions, significantly reduces corrosion of electroplating equipment, prolongs equipment life, reduces metal impurity pollution and maintenance costs caused by equipment corrosion, and at the same time, the anion composition in the wastewater is simpler, which is beneficial to subsequent resource recovery and treatment. DETAILED DESCRIPTION

[0025] In order to make the above objectives, features and advantages of the present application more clear and comprehensible, the specific embodiments of the present application are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be practiced in a number of different ways from those described herein without departing from the scope of the present application, and it is understood that similar improvements can be made by those skilled in the art without departing from the spirit of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0026] In addition, the terms "first", "second", and the like, are used only for the purpose of description, and should not be construed as indicating or implying relative importance or a specific number of the technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise explicitly specified.

[0027] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting", "fixing" and the like should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integral; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium, or internal communication of two elements, or interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0028] In the present application, unless otherwise explicitly specified and limited, the first feature "on" or "under" the second feature can be direct contact between the first and second features, or indirect contact between the first and second features through intermediate medium. Moreover, the first feature "above", "over" and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "under" and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0029] It should be noted that when an element is referred to as "fixed to" or "provided on" another element, it can be directly on the other element or there can be a middle element. When an element is referred to as "connected to" another element, it can be directly connected to the other element or there can be a middle element. The terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used herein are for illustrative purposes only and are not the only implementation. Example 1

[0030] The present application discloses an environmentally-friendly nickel plating solution, which comprises the following components by weight fraction: 100 parts of nickel sulfamate, 7.9-13.2 parts of nickel methylsulfonate, 9.2-11.8 parts of boric acid, 0.026-0.079 parts of sulfur-free stress reliever, 0.0026-0.013 parts of leveling agent, 0.013-0.053 parts of brightener, 0.13-0.53 parts of wetting agent, and 260-270 parts of deionized water.

[0031] The nickel sulfamate provides nickel ions, has extremely low internal stress, excellent plating layer toughness, and contains no sulfate and chloride ions, thereby reducing corrosive ions from the source and simplifying the wastewater treatment process.

[0032] The nickel methylsulfonate can replace nickel chloride to provide a small amount of chloride ions to maintain normal anode dissolution, and the methylsulfonate has good stability and is easily biodegradable and environmentally friendly.

[0033] The boric acid is used as a buffer to stabilize the pH value, and the amount thereof in the environmentally-friendly and safe range can avoid negative impact on the environment.

[0034] The sulfur-free stress reliever is a mixture of one or more of coumarin and its derivatives, and the natural coumarin or its synthetic derivatives are excellent sulfur-free stress relievers and refiners, can generate compressive stress to offset part of the tensile stress, make the plating layer white and fine, and have far better biodegradability than sulfur-containing compounds.

[0035] The leveling agent is a polyethyleneimine derivative, which can effectively improve the dispersion capacity and microscopic leveling property of the plating solution, has slow consumption rate and high stability, and the selection of low molecular weight and modified water-soluble PEI can effectively reduce the toxicity of the plating solution.

[0036] The brightener is an alkyne alcohol-ethylene oxide adduct, which has better water solubility, significantly reduced toxicity, is more stable in the plating solution, and has stronger brightening effect and leveling effect than butynediol.

[0037] The wetting agent is one of perfluoropolyether ether and alkyl polyglucoside, the perfluoropolyether ether is extremely stable, has extremely small amount, no foam or low foam, can significantly reduce the surface tension, and is suitable for high-speed electroplating; the alkyl polyglucoside is derived from plants, is completely biodegradable, non-toxic and harmless, is an excellent green surfactant, and has slightly more foam but is easy to control.

[0038] Further, in one embodiment, the pH value of the nickel plating solution is set to 3.8-4.5; in another embodiment, the pH value of the nickel plating solution is adjusted by a mixture of one or both of methylsulfonic acid and sulfamic acid to avoid the introduction of sulfate or chloride ions.

[0039] Further, in one embodiment, the operating temperature of the nickel plating environmentally friendly electroplating solution is set to 50-60°C.

[0040] Further, in one embodiment, the cathode current density of the nickel plating environmentally friendly electroplating solution in practical application is limited to 2-8 A / dm2; preferably, the cathode current density of the nickel plating environmentally friendly electroplating solution in practical application is limited to 3-5 A / dm2.

[0041] Further, in one embodiment, the stirring mode of the nickel plating environmentally friendly electroplating solution in practical application adopts one of mild air stirring or cathode movement, so as to ensure uniform distribution of the additives and prevent concentration polarization.

[0042] Further, the nickel plating environmentally friendly electroplating solution is prepared by the following steps: A1. Dissolve nickel sulfamate and nickel methylsulfonate in 1 / 2 volume of deionized water in the main tank under heating and stirring; A2. Completely dissolve boric acid in hot water (>60°C) in another container, and then pour into the main tank; A3. Add water to the main tank to approach the volume, and stir uniformly; A4. Adjust the pH to 3.8-4.5 by using methylsulfonic acid; A5. Add the metered coumarin (which can be first dissolved with a small amount of ethanol), PEI derivative, alkyne-ethylene oxide adduct, and wetting agent, and each addition needs to be stirred thoroughly; A6. Add water to the final volume, and stir uniformly; A7. Small current electrolysis (0.2-0.5 A / dm2, 4-6 hours) treatment to remove heavy metal impurities, and then test plating. Example 2

[0043] Different from Example 1, in this embodiment, the nickel plating environmentally friendly electroplating solution includes the following components by weight fraction: 100 parts of nickel sulfamate, 7.9-10.5 parts of nickel methylsulfonate, 9.2-10.5 parts of boric acid, 0.026-0.039 parts of sulfur-free stress reliever, 0.0026-0.0079 parts of leveling agent, 0.013-0.026 parts of brightener, 0.13-0.26 parts of wetting agent, and 260-263 parts of deionized water. Example 3

[0044] In this embodiment, the nickel plating environmental-friendly electroplating solution comprises the following components by weight fraction: 100 parts of nickel sulfamate, 10.5-13.2 parts of nickel methylsulfonate, 10.5-11.8 parts of boric acid, 0.039-0.079 parts of sulfur-free stress reliever, 0.0079-0.013 parts of leveling agent, 0.026-0.053 parts of brightener, 0.26-0.53 parts of wetting agent, and 263-270 parts of deionized water. Example 4

[0045] In this embodiment, the nickel plating environmental-friendly electroplating solution comprises the following components by weight fraction: 100 parts of nickel sulfamate, 7.9 parts of nickel methylsulfonate, 9.2 parts of boric acid, 0.026 parts of coumarin, 0.0026 parts of PEI derivative (50% aqueous solution), 0.013 parts of alkyne alcohol-ethylene oxide adduct, 0.13 parts of PFPE (50% aqueous solution), and 260 parts of deionized water. Example 5

[0046] In this embodiment, the nickel plating environmental-friendly electroplating solution comprises the following components by weight fraction: 100 parts of nickel sulfamate, 10.5 parts of nickel methylsulfonate, 10.5 parts of boric acid, 0.039 parts of coumarin, 0.0079 parts of PEI derivative (50% aqueous solution), 0.026 parts of alkyne alcohol-ethylene oxide adduct, 0.26 parts of PFPE (50% aqueous solution), and 263 parts of deionized water. Example 6

[0047] In this embodiment, the nickel plating environmental-friendly electroplating solution comprises the following components by weight fraction: 100 parts of nickel sulfamate, 13.2 parts of nickel methylsulfonate, 11.8 parts of boric acid, 0.079 parts of coumarin, 0.013 parts of PEI derivative (50% aqueous solution), 0.053 parts of alkyne alcohol-ethylene oxide adduct, 0.53 parts of PFPE (50% aqueous solution), and 270 parts of deionized water. Example 7

[0048] In this embodiment, the nickel plating environmental-friendly electroplating solution is prepared by the following steps: B1, take a 200 mL beaker, add about 100 mL deionized water, heat to 60-70°C; Under stirring, slowly add 40.0 grams of boric acid, stir until completely clear and transparent; place in a water bath for preservation, prevent cooling crystallization; B2. In a small beaker, dissolve 0.15 g of coumarin in about 20-30 mL of absolute ethanol; stir until completely dissolved to obtain a clear solution; this is solution A, seal and reserve; B3. Add about 500 mL of deionized water to a 1.5 liter main formulation vessel, start stirring and heat to 50-55°C; B4. Slowly add 380 g of nickel sulfamate and 40 g of nickel methanesulfonate in small portions under vigorous stirring; B5. Continue stirring for about 30 minutes until all solids are completely dissolved to obtain a deep green clear solution; B6. Slowly pour the previously prepared and kept hot aqueous boric acid solution into the main formulation vessel under stirring; B7. Rinse the beaker containing the boric acid with a small amount of deionized water and pour the rinse into the main vessel, ensuring no loss; B8. Continue stirring for 10 minutes to homogenize the solution; B9. Add deionized water to the vessel to bring the total volume close to 950 mL (allowing space for the addition of additives); B10. Stabilize the solution temperature at 55°C; B11. After calibrating the pH meter, insert it into the solution and slowly add the methanesulfonic acid dropwise under slow stirring to adjust the pH precisely to 4.2; the addition process should be slow and the pH continuously read to prevent over-acidification; B12. Add stress reliever: slowly add all of the pre-dissolved solution A (coumarin in ethanol) into the main solution under stirring; B13. Add high molecular leveling agent: accurately pipette 0.03 mL of PEI derivative; due to its viscosity, it should be added slowly at the center of the vortex formed by the stirring to allow its rapid dispersion and prevent localized coagulation; continue stirring for 15 minutes; B14. Add secondary brightener: accurately pipette 0.1 mL of alkyne alcohol-oxirane adduct and add under stirring; continue stirring for 10 minutes; B15. Add wetting agent: accurately pipette 1.0 mL of PFPE solution and add under stirring; continue stirring for 15-20 minutes to ensure complete mixing of all additives; B16. Final volume: accurately make up the solution volume to 1 liter with deionized water; stir for another 30 minutes; B17. Pour the prepared plating solution into the electrolytic cell; B18. Hang clean corrugated cathode sheets and anodes into the cell; B19. Start air agitation at 50-55°C and apply a low current density of 0.2-0.5 A / dm2; B20, electrolytic treatment 4-6 hours, or until the cathode plate deposited on the uniform, dense, no dark or gray stripes plating layer is stopped; this step can effectively remove heavy metal impurities in the solution.

[0049] In summary, the nickel plating layer environmental protection plating solution disclosed by the present application completely abandons the sulfur-containing primary brightener, and uses coumarin as a stress reliever. The sulfur in the traditional nickel plating layer can reduce its corrosion resistance, and when forming a multilayer system with a subsequent chromium layer, it can accelerate the longitudinal corrosion of the underlying nickel layer as an active anode. The sulfur-free semi-bright nickel layer obtained by the present application can greatly delay the corrosion penetration speed when combined with microporous / microcracked chromium, significantly improving the corrosion resistance of the overall coating, and at the same time, avoiding the entry of sulfur-containing organic matter into wastewater from the source, simplifying the wastewater treatment process. Specifically, the present application uses low-toxicity acetylenic alcohol-ethylene oxide adduct to replace traditional pyridine, quinoline derivatives; biodegradable APG or extremely stable and low-use PFPE is used to replace sodium dodecyl sulfate, thereby the selection of new additives is based on its low biological toxicity and high degradability, which greatly reduces the potential harm of electroplating waste liquid and cleaning wastewater to the environment, avoids the foul odor of pyridine substances, creates a safer and healthier workshop environment, meets the requirements of modern green manufacturing, and the new wetting agent is basically bubble-free or low-bubble, reducing material loss and environmental pollution caused by foam overflow; using nickel sulfamate as the main salt, supplemented with a small amount of nickel methylsulfate, avoiding high concentration of sulfate and chloride ions, significantly reducing the corrosion of electroplating equipment, prolonging the service life of the equipment, reducing the metal impurity pollution and maintenance cost caused by equipment corrosion, and at the same time, the anion composition in the wastewater is simpler, which is beneficial to subsequent resource recovery and treatment.

[0050] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described, but as long as the combinations of the technical features do not contradict, they should be considered within the scope of the present disclosure.

[0051] The above-described embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be construed as limiting the scope of the patent. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application. Therefore, the protection scope of the present patent should be subject to the appended claims.

Claims

1. An environmentally friendly electroplating solution for nickel plating, characterized in that, The nickel plating solution comprises, by weight fraction, 100 parts of nickel sulfamate, 7.9-13.2 parts of nickel methylsulfonate, 9.2-11.8 parts of boric acid, 0.026-0.079 parts of sulfur-free stress reliever, 0.0026-0.013 parts of leveling agent, 0.013-0.053 parts of brightener, 0.13-0.53 parts of wetting agent, and 260-270 parts of deionized water. The sulfur-free stress reliever is a mixture of one or more of coumarin and its derivatives. The leveling agent is a polyethyleneimine derivative. The brightener is an acetylenic alcohol-ethylene oxide adduct.

2. The nickel plating environmental-friendly electroplating solution according to claim 1, wherein, The wetting agent is one of perfluoropolyether ether and alkyl polyglucoside.

3. The nickel plating environmental-friendly electroplating solution according to claim 1, wherein The pH value of the nickel plating solution is set to 3.8-4.

5.

4. The nickel plating environmental-friendly electroplating solution according to claim 1, wherein the pH of the solution is 4.0-5.

0. The pH value of the nickel plating solution is adjusted by one or a mixture of both of methylsulfonic acid and amino sulfonic acid.

5. The nickel plating environmental-friendly electroplating solution according to claim 1, wherein the pH value of the solution is 4.0-5.

0. The nickel plating solution comprises, by weight fraction, 100 parts of nickel sulfamate, 7.9-10.5 parts of nickel methylsulfonate, 9.2-10.5 parts of boric acid, 0.026-0.039 parts of sulfur-free stress reliever, 0.0026-0.0079 parts of leveling agent, 0.013-0.026 parts of brightener, 0.13-0.26 parts of wetting agent, and 260-263 parts of deionized water.

6. The nickel plating environmental-friendly electroplating solution according to claim 1, wherein The nickel plating solution comprises, by weight fraction, 100 parts of nickel sulfamate, 10.5-13.2 parts of nickel methylsulfonate, 10.5-11.8 parts of boric acid, 0.039-0.079 parts of sulfur-free stress reliever, 0.0079-0.013 parts of leveling agent, 0.026-0.053 parts of brightener, 0.26-0.53 parts of wetting agent, and 263-270 parts of deionized water.

7. The nickel plating environmental-friendly electroplating solution according to claim 1, wherein the pH value of the solution is 4.0-5.

0. The nickel plating solution comprises, by weight fraction, 100 parts of nickel sulfamate, 7.9 parts of nickel methylsulfonate, 9.2 parts of boric acid, 0.026 parts of coumarin, 0.0026 parts of PEI derivative (50% aqueous solution), 0.013 parts of acetylenic alcohol-ethylene oxide adduct, 0.13 parts of PFPE (50% aqueous solution), and 260 parts of deionized water.

8. The nickel plating environmental-friendly electroplating solution according to claim 1, wherein, The nickel plating solution comprises, by weight fraction, 100 parts of nickel sulfamate, 10.5 parts of nickel methylsulfonate, 10.5 parts of boric acid, 0.039 parts of coumarin, 0.0079 parts of PEI derivative (50% aqueous solution), 0.026 parts of acetylenic alcohol-ethylene oxide adduct, 0.26 parts of PFPE (50% aqueous solution), and 263 parts of deionized water.

9. The nickel plating environmental-friendly electroplating solution according to claim 1, wherein, The nickel plating solution comprises, by weight fraction, 100 parts of nickel sulfamate, 13.2 parts of nickel methylsulfonate, 11.8 parts of boric acid, 0.079 parts of coumarin, 0.013 parts of PEI derivative (50% aqueous solution), 0.053 parts of acetylenic alcohol-ethylene oxide adduct, 0.53 parts of PFPE (50% aqueous solution), and 270 parts of deionized water.

10. The nickel plating environmental-friendly electroplating solution according to claim 1, wherein, The nickel plating layer environment-friendly plating solution is prepared by the following steps: A1, dissolving nickel sulfamate and nickel methyl sulfonate in 1 / 2 volume of deionized water in the main tank under heating and stirring; A2, completely dissolving boric acid in another container with hot water (> 60°C), and then pouring into the main tank; A3, adding water to the main tank to approach the volume, and stirring uniformly; A4, adjusting the pH to 3.8-4.5 with methyl sulfonic acid; A5, adding the metered coumarin (which can be first dissolved with a small amount of ethanol), PEI derivative, alkyne alcohol-ethylene oxide adduct, wetting agent, and stirring fully after each addition; A6, adding water to the final volume, and stirring uniformly; A7, small current electrolysis (0.2-0.5 A / dm², 4-6 hours) treatment to remove heavy metal impurities, and then plating.