Preparation method and application of green and environment-friendly fluorine-free and chromium-free passivation solution for tinplate

Abstract

This invention discloses a method for preparing and applying a green, environmentally friendly, fluorine-free, and chromium-free passivation solution for tinplate, belonging to the food packaging field. The invention involves reacting trimethoxysilane with a sulfur-containing silane coupling agent in anhydrous ethanol containing phosphoric acid to form a novel modified organosilicon polymer. This polymer is then reacted with tetrabutyl titanate and glacial acetic acid to form a clear solution. This solution is then added to a mixed solution formed sequentially by reacting titanium salt, zirconium salt, citric acid, sodium diethylhexyl sulfosuccinate, nitrate, and phosphoric acid to obtain a transparent, green, and environmentally friendly passivation solution. The passivation solution is roller-coated onto the surface of a tinplate to obtain a continuous and uniform coating, which is then cured by heating to obtain the passivation film. The passivation solution can form a nanoscale passivation film on the surface of the tinplate, exhibiting excellent adhesion to polymer coatings, as well as corrosion resistance, acid resistance, yellowing resistance, and excellent welding performance, meeting the application performance requirements of tinplate.

Description

Technical Field

[0001] This invention belongs to the field of food packaging, and specifically relates to the preparation method and application of a green and environmentally friendly fluorine-free and chromium-free passivation solution for tinplate. Background Technology

[0002] Tinplate, commonly known as tinplate, is a corrosion-resistant material made by plating a pure tin protective layer onto thin low-carbon steel sheets. During the tinplate production process, the surface of the tinplate, after electroplating and reflow processes, requires a final passivation treatment. Currently, chromate passivation is the primary method used for tinplate passivation. Patent CN102027157A proposes a solution containing at least one phosphate, at least 3 g / L of at least one titanium and zirconium compound, and at least one complexing agent, as well as a corresponding aqueous composition. Patent CN102066612A discloses one or more water-soluble compounds containing at least one atom of element titanium and / or zirconium, and one or more water-soluble compounds containing at least one fluorine atom. Patent CN110373661B proposes a passivation solution composed of fluorotitanate, fluorozirconate, permanganate, hydrofluoric acid, phosphate, and organosilane. Patent CN107488844B proposes a passivation solution composed of titanium salt, a phosphorus-containing compound, an oxidizing agent, a complexing agent, and water. Patent CN1416478A proposes a forming solution containing phosphate ions, tin ions, and epoxy silane coupling agents, which, through impregnation or electrolytic treatment, achieves excellent coating adhesion, corrosion resistance, and processability. Patent CN104711567A proposes an alcohol system composed of ethanol, tetrabutyl titanate, acetylacetone, acetic acid, and n-butanol, which meets requirements for adhesion and weldability.

[0003] Typically, the chromate passivation process for tinplate uses dichromate, specifically sodium dichromate. This contains highly toxic hexavalent chromium, a carcinogen that severely pollutes the environment and poses a significant health hazard. The harm caused by chromate passivation is particularly pronounced for tinplate used in the food and beverage industry, and it is destined to be phased out in today's increasingly environmentally conscious world. Furthermore, fluoride is widely present in natural water bodies and is present in all human tissues, but excessive fluoride is harmful. The lethal dose of sodium fluoride for humans is 6–12g. Long-term exposure to high levels of fluoride can lead to bone fluorosis, primarily manifesting as joint pain and stiffness, ligament hardening and calcification, and can cause bone deformities, muscle weakness, and nerve damage, making bones brittle. Therefore, adopting a green and environmentally friendly chromium-free and fluoride-free passivation process to replace the chromium passivation process has become an inevitable choice for the tinplate manufacturing industry. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention aims to provide a method for preparing and applying a green and environmentally friendly fluorine-free and chromium-free passivation plating solution for tinplate. This solution yields a passivation film with excellent corrosion resistance, superior adhesion to polymer coatings, acid and yellowing resistance, and excellent weldability, thus meeting the application performance requirements of tinplate. The specific technical solution is as follows:

[0005] The preparation method of a green and environmentally friendly fluorine-free and chromium-free passivation solution for tin-plated sheets includes the following steps:

[0006] Step 1: Add trimethoxysilane and sulfur-containing silane coupling agent to anhydrous ethanol and stir to form mixed solution A; Mixed solution A reacts with water and phosphoric acid, and after complete hydrolysis, forms solution B;

[0007] Step 2: Add tetrabutyl titanate to anhydrous ethanol and react under stirring. Then add glacial acetic acid and solution B, and continue stirring to react and form solution C.

[0008] Step 3: Add potassium titanium oxalate, ammonium zirconium carbonate, ammonium dihydrogen phosphate, sodium nitrate, citric acid, and sodium diethylhexyl sulfosuccinate to deionized water in sequence, stir well, and let it dissolve completely to form a clear solution D.

[0009] Step 4: Slowly add solution C and phosphoric acid to solution D in sequence, stir, and let stand to obtain a transparent, green, environmentally friendly, fluorine-free, and chromium-free passivation solution.

[0010] In step 1, the trimethoxysilane is 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; the sulfur-containing silane coupling agent is a triethoxy-containing sulfur-containing silane.

[0011] In the mixed solution A, the amounts of trimethoxysilane, sulfur-containing silane coupling agent, and anhydrous ethanol added, by mass percentage, are as follows: trimethoxysilane 2%–6%, sulfur-containing silane coupling agent 10%–15%, and anhydrous ethanol 80%–85%; wherein, the mass ratio of trimethoxysilane to sulfur-containing silane coupling agent is trimethoxysilane: sulfur-containing silane coupling agent = 1:(2–3);

[0012] When preparing solution B, the amounts of solution A, deionized water, and phosphoric acid added, by mass percentage, are as follows: solution A is 95%–98%, phosphoric acid is 0.5%–2%, and the remainder is deionized water; wherein, the concentration of phosphoric acid is 1 mol / L.

[0013] The stirring time is 5 min to 15 min; the reaction time of solution A with water and phosphoric acid is 60 min to 180 min.

[0014] In step 2, the amounts of tetrabutyl titanate, glacial acetic acid, and solution B added, by mass percentage, are as follows: tetrabutyl titanate 1-3%, glacial acetic acid 5-8%, solution B 3-5%; the remainder is anhydrous ethanol.

[0015] When the tetrabutyl titanate is added to anhydrous ethanol, the stirring speed is 550-650 r / min and the reaction time is 20-40 min.

[0016] The stirring speed is 550-650 r / min, and the reaction time is 60-120 min.

[0017] In step 3, the amounts of potassium titanium oxalate, ammonium zirconium carbonate, ammonium dihydrogen phosphate, sodium nitrate, citric acid, and sodium diethylhexyl sulfosuccinate added, by mass percentage, are as follows: potassium titanium oxalate 0.01%–0.04%, ammonium zirconium carbonate 0.01%–0.06%, dihydrogen phosphate 0.001%–0.006%, sodium nitrate 0.001%–0.006%, citric acid 0.01%–0.04%, sodium diethylhexyl sulfosuccinate 0.001%–0.006%, with the remainder being deionized water.

[0018] In step 4, the phosphoric acid concentration is 0.5 mol / L to 2 mol / L;

[0019] The amounts of solution C and phosphoric acid added, by mass percentage, are 0.05%–0.1% for solution C and 1%–4% for phosphoric acid; the content of solution D is 95%–98%.

[0020] The stirring speed is 550-650 r / min, and the settling time is 12-24 h.

[0021] The application method of the green and environmentally friendly fluorine-free passivation solution for tin-plated plates includes the following steps:

[0022] (1) Dilute the green and environmentally friendly fluorine-free and chromium-free passivation solution for tin-plated boards with deionized water;

[0023] (2) The diluted passivation solution is evenly coated onto the surface of the tin-plated plate to homogenize the surface droplets and obtain a continuous and uniform passivation solution film.

[0024] (3) Heat the tinplate, and the liquid film reacts with the tin layer to solidify the passivation film of the tinplate.

[0025] In step (1), the volume ratio of deionized water to passivation solution is: deionized water: passivation solution = 10: (1-6).

[0026] In step (2), the coating equipment is a nozzle, and the homogenization treatment is carried out by a roller coating device or an immersion device.

[0027] In step (3), the heating method is one or a combination of hot air, infrared, and electromagnetic induction, heating the tinplate to a temperature of 100℃~150℃; the passivation film thickness of the tinplate is 3mg / m. 2 ~5mg / m 2 .

[0028] The present invention provides a method for preparing and applying a green and environmentally friendly fluorine-free and chromium-free passivation solution for tin-plated plates. Compared with the prior art, the advantages are as follows:

[0029] 1. The passivation solution prepared by the method of this invention uses a silane coupling agent to connect titanium and zirconium elements to form a cross-linked and dense network film framework structure, which has high density and good corrosion protection effect on the tin-plated plate surface; phosphoric acid, as a pH adjuster, can also increase the phosphorus content in the chromium-free passivation solution, which is beneficial to improving the corrosion resistance and oxidation resistance of the chromium-free passivated tin-plated plate; sodium nitrate is an oxidant to accelerate the film formation process and improve the passivation efficiency; citric acid is an organic chelating agent to chelate titanium and zirconium ions in the passivation solution; sodium diethylhexyl sulfosuccinate, as a surfactant, plays a super-wetting and dispersing role, making the passivation solution easier to spread evenly on the tin-plated plate surface.

[0030] 2. The passivation solution prepared by the method of this invention is green, safe and environmentally friendly. It uses water as the main medium and does not contain toxic, harmful or organic solvent components. Chromium-free passivation solves the technical problems of chromium in existing chromate passivation solutions and fluorine in chromium-free passivation solutions. It meets the special packaging requirements of tinplate, reduces the burden of wastewater treatment and environmental pollution, and meets the requirements of RoHS and REACH directives.

[0031] 3. The passivation solution prepared by the method of the present invention can obtain a nanoscale passivation film on the surface of tin-plated plate, and has minimal impact on the performance of the tin layer on the surface of tin-plated plate;

[0032] 4. The chromium-free passivated tin-plated steel sheet obtained by the passivation solution prepared by the method of the present invention has salt spray resistance, porosity, acid resistance and adhesion, etc., which all reach or exceed the level of tin-plated steel sheets obtained by chromate passivation process.

[0033] 5. The chromium-free passivation solution prepared by the method of the present invention does not require electrolytic passivation and can be directly applied by roller coating. Compared with the electrolytic passivation process, it saves electricity significantly, and the process is easy to control, does not generate waste liquid, and is environmentally friendly. Detailed Implementation

[0034] The present invention will be further described below with reference to specific implementation examples, but the present invention is not limited to these embodiments.

[0035] The preparation was carried out using commercially available analytical grade trimethoxysilane, sulfur-containing silane coupling agent, potassium titanium oxalate, ammonium zirconium carbonate, ammonium dihydrogen phosphate, sodium nitrate, citric acid, sodium diethylhexyl sulfosuccinate, and phosphoric acid.

[0036] Example 1

[0037] Preparation of green and environmentally friendly chromium-free and fluorine-free passivation solution:

[0038] Using a pipette, 1000 μL of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and 2450 μL of bis-[3-(triethoxysilyl)propyl]tetrasulfide were added to 16.8 g of anhydrous ethanol. The mixture was mechanically stirred for 10 min to form a homogeneous solution. Then, 0.77 g of deionized water was added, and the solution was diluted with 30 μL of 1 mol / L... After adjusting the pH with H3PO4 and continuing the reaction for 1 hour, a colorless and transparent organosilicon-modified organosilicon polymer A was obtained. 0.1 ml of tetrabutyl titanate was slowly added to anhydrous ethanol and stirred slowly. After reacting for 20 minutes, 0.5 ml of glacial acetic acid and 0.5 ml of solution A were added and stirred evenly. After reacting for 60 minutes, solution B was formed. The components and ratios of this fluorine-free and chromium-free passivation solution are as follows: modified organosilicon polymer B (0.4 g / L), potassium titanium oxalate (0.1 g / L), ammonium zirconium carbonate (0.3 g / L), citric acid (0.5 g / L), sodium diethylhexyl sulfosuccinate (0.05 g / L), sodium nitrate (0.02 g / L), 40.0 mL / L of 1 mol / L H3PO4, and the remainder was deionized water.

[0039] The passivation of tin-plated steel sheets using the above-mentioned fluorine-free and chromium-free passivation solution specifically includes the following steps:

[0040] (1) Dilute the above passivation solution with deionized water at a volume ratio of 6% and let it stand for 12 hours to obtain the working solution of green and environmentally friendly chromium-free and fluorine-free passivation solution.

[0041] (2) Use an atomizing nozzle device to evenly disperse the working fluid droplets onto the tinplate surface, and then use a roller coating device to homogenize the droplets to obtain a continuous and uniform liquid film.

[0042] (3) Heat the tin-plated plate with hot air to obtain a plate temperature (PMT = 125℃), so that the liquid film reacts with the tin layer and solidifies to obtain the plating film.

[0043] In this embodiment, a colorless coating can be formed on the surface of the tinplate through the above treatment. According to QB / T2763-2006 "Coated Tin (Chromium) Thin Steel Sheets", the adhesion test results show that its adhesion level is Grade 1, which is excellent. According to ISV (GB / T22316 Test Method for Corrosion Resistance of Electroplated Tin Steel Sheets), its salt spray resistance level is Grade 1, and its corrosion resistance reaches the level of chromium film. In the acid resistance test (3% acetic acid solution, 121℃×60min), the coating film has no bubbles, no peeling, no discoloration, and no whitening, and the acid resistance level reaches Grade 1. In the yellowing resistance test (hot air drying oven, 200℃×20min), there is no yellowing after printing and coating baking, which shows excellent comprehensive performance.

[0044] Example 2

[0045] Preparation of green and environmentally friendly chromium-free and fluorine-free passivation solution:

[0046] Using a pipette, 980 μL of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and 2250 μL of bis-[3-(triethoxysilyl)propyl]tetrasulfide were added to 17.2 g of anhydrous ethanol. The mixture was mechanically stirred for 10 min to form a homogeneous solution. Then, 0.95 g of deionized water was added, and the solution was diluted with 30 μL of 1 mol / L... After adjusting the pH with H3PO4 and continuing the reaction for 1.5 h, a colorless and transparent organosilicon-modified organosilicon polymer A was obtained. 0.1 ml of tetrabutyl titanate was slowly added to anhydrous ethanol and stirred slowly. After reacting for 20 min, 0.5 ml of glacial acetic acid and 0.5 ml of solution A were added and stirred evenly. After reacting for 60 min, solution B was formed. The components and ratios of this fluorine-free and chromium-free passivation solution are as follows: modified organosilicon polymer B (0.6 g / L), potassium titanium oxalate (0.3 g / L), ammonium zirconium carbonate (0.4 g / L), citric acid (0.5 g / L), sodium diethylhexyl sulfosuccinate (0.06 g / L), sodium nitrate (0.03 g / L), 60.0 mL / L of 1 mol / L H3PO4, and the remainder is deionized water.

[0047] The method for passivating tin-plated steel sheets using the above-mentioned fluorine-free and chromium-free passivation solution includes the following steps:

[0048] (1) Dilute the above passivation solution with deionized water at a volume ratio of 7% and let it stand for 12 hours to obtain the working solution of green and environmentally friendly chromium-free and fluorine-free passivation solution.

[0049] (2) Use an atomizing nozzle device to evenly disperse the working fluid droplets onto the tinplate surface, and then use a roller coating device to homogenize the droplets to obtain a continuous and uniform liquid film.

[0050] (3) Heat the tin-plated plate with hot air to obtain a plate temperature (PMT = 140℃), so that the liquid film reacts with the tin layer and solidifies to obtain a coating.

[0051] In this embodiment, a colorless coating can be formed on the surface of the tinplate through the above treatment. Adhesion test was conducted according to QB / T2763-2006 "Coated Tin (Chromium) Thin Steel Sheet". The results show that its adhesion level is Grade 1, which is excellent. According to ISV (GB / T22316 Test Method for Corrosion Resistance of Electroplated Tin Steel Sheet), its salt spray resistance level is Grade 1, and its corrosion resistance reaches the level of chromium film. In the acid resistance test (3% acetic acid solution, 121℃×60min), the coating film showed no bubbles, no peeling, no discoloration, and no whitening, and the acid resistance level reached Grade 1. In the yellowing resistance test (hot air drying oven, 200℃×20min), there was no yellowing after printing and baking, which shows excellent comprehensive performance.

[0052] Example 3

[0053] Preparation of green and environmentally friendly chromium-free and fluorine-free passivation solution:

[0054] Using a pipette, 1350 μL of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and 2650 μL of bis-[3-(triethoxysilyl)propyl]tetrasulfide were added to 18.5 g of anhydrous ethanol. The mixture was mechanically stirred for 10 min to form a homogeneous solution. 1.1 g of deionized water was then added, and the solution was diluted with 30 μL of 1 mol / L... After adjusting the pH with H3PO4 and continuing the reaction for 1.5 h, a colorless and transparent organosilicon-modified organosilicon polymer A was obtained. 0.1 ml of tetrabutyl titanate was slowly added to anhydrous ethanol and stirred slowly. After reacting for 20 min, 0.5 ml of glacial acetic acid and 0.5 ml of solution A were added and stirred evenly. After reacting for 60 min, solution B was formed. The components and ratios of this fluorine-free and chromium-free passivation solution are as follows: modified organosilicon polymer B (0.8 g / L), potassium titanium oxalate (0.3 g / L), ammonium zirconium carbonate (0.4 g / L), citric acid (0.55 g / L), sodium diethylhexyl sulfosuccinate (0.07 g / L), sodium nitrate (0.03 g / L), 80.0 mL / L of 1 mol / L H3PO4, and the remainder is deionized water.

[0055] The method for passivating tin-plated steel sheets using the above-mentioned fluorine-free and chromium-free passivation solution includes the following steps:

[0056] (1) Dilute the above passivation solution with deionized water at a volume ratio of 9% and let it stand for 12 hours to obtain the working solution of green and environmentally friendly chromium-free and fluorine-free passivation solution.

[0057] (2) Use an atomizing nozzle device to evenly disperse the working fluid droplets onto the tinplate surface, and then use a roller coating device to homogenize the droplets to obtain a continuous and uniform liquid film.

[0058] (3) Heat the tin-plated plate with hot air to obtain a plate temperature (PMT = 145℃) so that the liquid film reacts with the tin layer and solidifies to obtain a coating.

[0059] In this embodiment, a colorless coating can be formed on the surface of the tinplate through the above treatment. According to QB / T2763-2006 "Coated Tin (Chromium) Thin Steel Sheets", the adhesion test results show that its adhesion level is Grade 1, which is excellent. According to ISV (GB / T22316 Test Method for Corrosion Resistance of Electroplated Tin Steel Sheets), its salt spray resistance level is Grade 1, and its corrosion resistance reaches the level of chromium film. In the acid resistance test (3% acetic acid solution, 121℃×60min), the coating film has no bubbles, no peeling, no discoloration, and no whitening, and the acid resistance level reaches Grade 1. In the yellowing resistance test (hot air drying oven, 200℃×20min), there is no yellowing after printing and coating baking, which shows excellent comprehensive performance.

[0060] Comparative Example 1

[0061] Preparation of green and environmentally friendly chromium-free and fluorine-free passivation solution:

[0062] Using a pipette, 1150 μL of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and 2550 μL of bis-[3-(triethoxysilyl)propyl]tetrasulfide were added to 18.5 g of anhydrous ethanol. The mixture was mechanically stirred for 10 min to form a homogeneous solution. 1.1 g of deionized water was then added, and the solution was diluted with 30 μL of 1 mol / L... After adjusting the pH with H3PO4 and continuing the reaction for 1.5 h, a colorless and transparent organosilicon-modified organosilicon polymer A was obtained. 0.1 ml of tetrabutyl titanate was slowly added to anhydrous ethanol and stirred slowly. After reacting for 20 min, 0.5 ml of glacial acetic acid and 0.5 ml of solution A were added and stirred evenly. After reacting for 60 min, solution B was formed. The components and ratios of this fluorine-free and chromium-free passivation solution are as follows: modified organosilicon polymer B (0.8 g / L), potassium titanium oxalate (0.3 g / L), ammonium zirconium carbonate (0.1 g / L), citric acid (0.55 g / L), sodium nitrate (0.03 g / L), 10.0 mL / L of 1 mol / L H3PO4, and the remainder is deionized water.

[0063] The method for passivating tin-plated steel sheets using the above-mentioned fluorine-free and chromium-free passivation solution includes the following steps:

[0064] (1) Dilute the above passivation solution with deionized water at a volume ratio of 9% and let it stand for 12 hours to obtain the working solution of green and environmentally friendly chromium-free and fluorine-free passivation solution.

[0065] (2) Use an atomizing nozzle device to evenly disperse the working fluid droplets onto the tinplate surface, and then use a roller coating device to homogenize the droplets to obtain a continuous and uniform liquid film.

[0066] (3) Heat the tin-plated plate with hot air to obtain a plate temperature (PMT = 145℃) so that the liquid film reacts with the tin layer and solidifies to obtain a coating.

[0067] In this embodiment, a colorless coating can be formed on the surface of the tinplate through the above treatment. According to QB / T2763-2006 "Coated Tin (Chromium) Thin Steel Sheets", the adhesion test results show that its adhesion level is 5, which is poor. According to ISV (GB / T22316 Test Method for Corrosion Resistance of Electroplated Tin Steel Sheets), its salt spray resistance level is 3, which does not reach the level of chromium film. In the acid resistance test (3% acetic acid solution, 121℃×60min), the coating film has no bubbles, no peeling, no discoloration, and no whitening, and the acid resistance level reaches 1. In the yellowing resistance test (hot air drying oven, 200℃×20min), there is no yellowing after printing and coating baking, which shows excellent comprehensive performance.

Claims

1. A method for preparing a green and environmentally friendly fluorine-free and chromium-free passivation solution for tin-plated plates, characterized in that, It includes the following steps: Step 1: Add trimethoxysilane and sulfur-containing silane coupling agent to anhydrous ethanol and stir to form mixed solution A; Mixed solution A reacts with water and phosphoric acid, and after complete hydrolysis, forms solution B; Step 2: Add tetrabutyl titanate to anhydrous ethanol and react under stirring. Then add glacial acetic acid and solution B, and continue stirring to react and form solution C. Step 3: Add potassium titanium oxalate, ammonium zirconium carbonate, ammonium dihydrogen phosphate, sodium nitrate, citric acid, and sodium diethylhexyl sulfosuccinate to deionized water in sequence, stir well, and let it dissolve completely to form a clear solution D. Step 4: Slowly add solution C and phosphoric acid to solution D in sequence, stir, and let stand to obtain a transparent, green, environmentally friendly, fluorine-free, and chromium-free passivation solution; In step 1, the trimethoxysilane is 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; the sulfur-containing silane coupling agent is a triethoxy-containing sulfur-containing silane. In the mixed solution A, the amounts of trimethoxysilane, sulfur-containing silane coupling agent, and anhydrous ethanol added, by mass percentage, are as follows: trimethoxysilane 2%~6%, sulfur-containing silane coupling agent 10%~15%, and anhydrous ethanol 80%~85%; wherein, the mass ratio of trimethoxysilane to sulfur-containing silane coupling agent is trimethoxysilane : sulfur-containing silane coupling agent = 1 : (2~3). When preparing solution B, the amounts of solution A, deionized water, and phosphoric acid added, by mass percentage, are as follows: solution A is 95%~98%, phosphoric acid is 0.5%~2%, and the remainder is deionized water; wherein, the concentration of phosphoric acid is 1 mol / L. The stirring time is 5 min to 15 min; the reaction time of solution A with water and phosphoric acid is 60 min to 180 min; In step 2, the amounts of tetrabutyl titanate, glacial acetic acid, and solution B added, by mass percentage, are as follows: tetrabutyl titanate 1-3%, glacial acetic acid 5-8%, solution B 3-5%; the remainder is anhydrous ethanol. When the tetrabutyl titanate is added to anhydrous ethanol, the stirring speed is 550~650 r / min and the reaction time is 20 min~40 min; The stirring speed during the continued stirring is 550~650 r / min, and the reaction time is 60 min~120 min; In step 3, the amounts of potassium titanium oxalate, ammonium zirconium carbonate, ammonium dihydrogen phosphate, sodium nitrate, citric acid, and sodium diethylhexyl sulfosuccinate added, by mass percentage, are as follows: potassium titanium oxalate 0.01%~0.04%, ammonium zirconium carbonate 0.01%~0.06%, dihydrogen phosphate 0.001%~0.006%, sodium nitrate 0.001%~0.006%, citric acid 0.01%~0.04%, sodium diethylhexyl sulfosuccinate 0.001%~0.006%, with the remainder being deionized water; In step 4, the phosphoric acid concentration is 0.5 mol / L to 2 mol / L; The amounts of solution C and phosphoric acid added, by mass percentage, are 0.05%~0.1% for solution C and 1%~4% for phosphoric acid; the content of solution D is 95%~98%. The stirring speed is 550~650 r / min, and the standing time is 12h~24h.

2. The application of the green and environmentally friendly fluorine-free and chromium-free passivation solution for tin-plated plates prepared by the method of claim 1, characterized in that, It includes the following steps: (1) Dilute the green and environmentally friendly fluorine-free and chromium-free passivation solution for tin-plated boards with deionized water; (2) The diluted passivation solution is evenly coated onto the surface of the tin-plated plate to homogenize the surface droplets and obtain a continuous and uniform passivation solution film. (3) Heat the tinplate, and the liquid film reacts with the tin layer to solidify the passivation film of the tinplate.

3. The application of the green and environmentally friendly fluorine-free and chromium-free passivation solution for tin-plated plates according to claim 2, characterized in that, In step (1), the volume ratio of deionized water to passivation solution is: deionized water: passivation solution = 10:(1-6).

4. The application of the green and environmentally friendly fluorine-free and chromium-free passivation solution for tin-plated plates according to claim 2, characterized in that, In step (2), the coating equipment is a nozzle, and the homogenization treatment is carried out by a roller coating device or an immersion device.

5. The application of the green and environmentally friendly fluorine-free and chromium-free passivation solution for tin-plated plates according to claim 2, characterized in that, In step (3), the heating method is one or a combination of hot air, infrared, and electromagnetic induction, heating the tinplate to a temperature of 100 ℃~150 ℃; the passivation film thickness of the tinplate is 3 mg / m. 2 ~5mg / m 2 .