Preparation method of cadmium titanium plating test titanium oxychloride solution

Abstract

The present application relates to the technical field of surface treatment, in particular to a preparation method of titanium oxychloride solution for cadmium-titanium plating test. In order to solve the technical problem that it is difficult to effectively prepare cadmium-titanium plating bath liquid meeting the requirements of navigation marks in the research and development stage, the present application uses industrial-grade titanium oxysulfate as raw material, adopts semi-quantitative analysis, and conveniently and effectively prepares the titanium oxychloride solution required in the research stage without complicated calibration process. By adjusting the addition amount of hydrochloric acid and the dissolution time of titanium hydroxide precipitation, the problem of easy turbidity of the plating bath liquid after adding the titanium oxychloride solution into the cadmium-titanium plating bath liquid is solved, thereby improving the stability of the cadmium-titanium plating bath liquid. Based on the preparation method, the difficulty of researchers in the development stage of cadmium-titanium plating technology is reduced, and the foundation for the effective development of subsequent electroplating process and electroplating parameter research is laid.

Description

Technical Field

[0001] This invention relates to the field of surface treatment technology, and specifically to a method for preparing a titanium oxychloride solution for electroplating cadmium titanium. Background Technology

[0002] High-strength steel parts can be protected in various ways, such as surface metallization, thermal spraying, and surface plating. Among these, cyanide-free cadmium-titanium plating is currently considered an ideal protection method for high-strength steel. Using this process yields a cadmium-titanium alloy plating layer with strong adhesion and fine crystal structure, containing 0.1%-0.7% titanium. Compared to a single cadmium plating layer, this significantly improves the corrosion resistance and hydrogen embrittlement resistance of the base material. Furthermore, the plating solution for cadmium-titanium plating does not contain highly toxic substances, and the process is convenient. Therefore, in-depth research into cadmium-titanium plating technology is essential and of great significance for scientifically guiding the research of plating processes and parameters.

[0003] To conduct in-depth research on cadmium-titanium electroplating technology, the first step is to successfully prepare the cadmium-titanium electroplating bath solution. In the preparation of the high-strength steel cadmium-titanium electroplating bath solution, metallic titanium is added in the form of titanium oxychloride. However, titanium oxychloride, essential for the cadmium-titanium electroplating process, is a highly unstable compound that can undergo complexation reactions with other chemicals in the plating bath and cannot be left exposed to air for extended periods. Furthermore, there is no commercially available finished titanium oxychloride solution; the required solution must be prepared in-house. Therefore, rationally controlling the parameters during the preparation of the titanium oxychloride solution to formulate a cadmium-titanium electroplating bath solution that meets the technical requirements of 2g / L to 5g / L titanium content in aviation standards is crucial for conducting research on cadmium-titanium electroplating technology.

[0004] Although many scholars have studied the preparation of titanium oxychloride solutions, most related research focuses on methods for preparing large-dose, industrial-grade solutions, with limited research on small-dose, experimental solutions. Existing research and navigational standards also present relatively simplified preparation processes for titanium oxychloride solutions, increasing the difficulty for researchers in developing cadmium-titanium electroplating technology. The preparation process is complex and involves multiple calibration procedures, such as detecting titanium content and sulfate ions in the titanium hydroxide cleaning solution, making it difficult for researchers to formulate cadmium-titanium plating baths that meet navigational standards for process analysis. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a method for preparing a titanium oxychloride solution for cadmium-titanium electroplating experiments. This method solves the technical challenge of effectively preparing cadmium-titanium plating bath solutions that meet aviation standards during the research and development phase. While achieving the above objectives, a semi-quantitative analysis method is employed to minimize experimental costs and complexity. Furthermore, by solidifying parameters such as the amount of hydrochloric acid added and the dissolution time of titanium hydroxide precipitate, the problem of turbidity in the cadmium-titanium plating bath solution after its addition is resolved, thereby improving the stability of the cadmium-titanium plating bath solution.

[0006] This invention first provides a method for preparing a titanium oxychloride solution for cadmium-titanium electroplating experiments, comprising the following steps:

[0007] (1) Weigh out titanium oxysulfate, add 3 to 4 times its weight of water, stir well and let stand to obtain a colorless and transparent titanium oxysulfate aqueous solution; the amount of titanium oxysulfate weighed is calculated based on the volume of the test tank liquid for cadmium titanium electroplating, with a titanium content of 5 g / L.

[0008] (2) Adding ammonia to the titanium oxysulfate aqueous solution produces titanium hydroxide precipitate. Stop adding ammonia when the pH is 7-8.

[0009] (3) Using a siphon method, the titanium hydroxide precipitate obtained in step (2) is washed with water until no precipitate is produced when barium chloride solution is added to the water after washing. The precipitate is filtered with a fine cloth and squeezed dry to obtain the washed titanium hydroxide precipitate. The dryness of the titanium hydroxide precipitate is based on the theoretical metallic titanium content. The titanium hydroxide precipitate obtained from 1g of titanium is 30-35g.

[0010] (4) The titanium hydroxide precipitate after cleaning in step (3) is dissolved in chemically pure hydrochloric acid. After the titanium hydroxide precipitate has completely dissolved, it is filtered to remove impurities. The filtrate is titanium oxychloride solution. The amount of hydrochloric acid added is based on the theoretical titanium content, and the ratio of titanium (g): hydrochloric acid (mL) is 1:5 to 1:6.

[0011] In step (1), the titanium oxysulfate is industrial titanium oxysulfate, and 100g of industrial titanium oxysulfate contains 9-10g of titanium.

[0012] In step (1), 3.5 times the weight of deionized water is added.

[0013] In step (2), the ammonia water is prepared by mixing concentrated ammonia water with a mass concentration of 25% with water in a volume ratio of 1:1.

[0014] In step (2), ammonia is added to the titanium oxysulfate aqueous solution at a rate of 35 mL / min.

[0015] In step (2), the temperature of the entire process is controlled between 0℃ and 10℃.

[0016] In step (3), the amount of titanium hydroxide precipitate obtained from 1g of titanium with a dryness of 30g is considered.

[0017] In step (4), the ratio of titanium (g) to hydrochloric acid (mL) is 1:5.

[0018] The hydrochloric acid has a density of 1.19 g / mL.

[0019] Beneficial Effects: While most related research focuses on the preparation of large-dose, industrial-grade titanium oxychloride solutions, this invention proposes a convenient and efficient method for preparing experimental titanium oxychloride solutions. This method uses industrial-grade titanium oxysulfate as a raw material and employs semi-quantitative analysis, conveniently and effectively preparing the experimental titanium oxychloride solutions required for the research stage without cumbersome calibration processes. This method reduces the difficulty for researchers in the development stage of cadmium-titanium electroplating technology, laying the foundation for the effective development of subsequent electroplating processes and parameters. Detailed Implementation

[0020] This invention provides a method for preparing a titanium oxychloride solution for cadmium-titanium electroplating experiments. This method uses industrial-grade titanium oxysulfate as a raw material and employs a semi-quantitative analysis approach. Without a cumbersome calibration process, it conveniently and effectively prepares the titanium oxychloride solution required for the research phase, and comprehensively conducts process research on cadmium-titanium electroplating technology. This provides theoretical support for the implementation of cadmium-titanium electroplating processes in production, and enables the effective development of research on electroplating processes and parameters.

[0021] The specific implementation method is as follows:

[0022] The preparation method of titanium oxychloride solution for cadmium-titanium electroplating includes the following steps:

[0023] (1) Determine the required volume of the cadmium-titanium electroplating bath and calculate the required mass of metallic titanium according to the upper limit of the range specified in the navigation standard: According to the bath composition described in navigation standard HB / Z107-86, the content of metallic titanium is 2 g / L to 5 g / L. If the required volume of the test bath is K liters, the metallic titanium content calculated according to the upper limit of the range is 5 K grams. 5 K means that the metallic titanium content is 2 g / L to 5 g / L. Calculated according to the upper limit of 5 g / L, the metallic titanium content in K liters of bath is 5 × K.

[0024] (2) Calculate the consumption of titanium oxysulfate raw material based on the upper limit of the mass of metallic titanium obtained in step (1): According to the navigation standard HB / Z107-86, 100g of industrial titanium oxysulfate contains 9-10g of titanium. With K liters of test bath solution, the consumption of titanium oxysulfate calculated based on the upper limit is 50K grams.

[0025] (3) Weigh titanium oxysulfate into a glass container according to the consumption value of titanium oxysulfate, add 3 to 4 times the weight of deionized water, stir thoroughly and let stand for 24 hours to obtain a colorless and transparent titanium oxysulfate aqueous solution.

[0026] In a preferred embodiment of the present invention, 3.5 times the weight of deionized water is added.

[0027] (4) Slowly add ammonia water to the filtered titanium oxysulfate aqueous solution while stirring. A large amount of white titanium hydroxide precipitate will be produced. Stop adding ammonia water when the pH is 7-8.

[0028] In a preferred embodiment of the present invention, the 1:1 ammonia solution mentioned in step (4) is prepared by mixing concentrated ammonia solution with a mass concentration of 25% and water in a volume ratio of 1:1.

[0029] In a preferred embodiment of the present invention, ammonia water with a volume ratio of 1:1 is added to an aqueous solution of titanium oxysulfate at a rate of 35 mL / min, and the addition of ammonia water is stopped when the pH is 7-8.

[0030] In a preferred embodiment of the present invention, the temperature of the entire process in step (4) is controlled at 0°C to 10°C.

[0031] The reaction mechanism in step (4) is: TiOSO4 + 2NH3·H2O + H2O = Ti(OH)4↓ + (NH4)2SO4.

[0032] (5) The titanium hydroxide precipitate prepared in step (4) is repeatedly washed with a large amount of deionized water more than 5 times using the siphon method until no precipitation is produced when barium chloride solution is added to the water after washing, ensuring that the sulfate ions are basically washed away. Then, it is filtered with a polyester cloth and squeezed dry. During the squeezing process, the mass of the obtained titanium hydroxide precipitate is continuously weighed. The squeezing is stopped when the dryness of the titanium hydroxide precipitate is controlled to be 30-35g of titanium hydroxide precipitate prepared from 1g of titanium.

[0033] In a preferred embodiment of the present invention, the wetness of the titanium hydroxide precipitate is controlled to be 1g of titanium and 30g of titanium hydroxide precipitate. If the required volume of the test bath is K liters, the calculated titanium content based on the upper limit is 5K grams, and the obtained titanium hydroxide precipitate is 150K grams.

[0034] Titanium hydroxide needs to be dissolved in hydrochloric acid. For details of the dissolution operation, please refer to step (6). The dryness of the titanium hydroxide precipitate is directly related to the amount of hydrochloric acid added when preparing titanium oxychloride. If the dryness of the titanium hydroxide precipitate is not well controlled during the later hydrochloric acid dissolution process, it will directly lead to the inability to obtain clear titanium oxychloride after adding hydrochloric acid, which is not conducive to the preparation of titanium oxychloride solution with standard concentration.

[0035] (6) The titanium hydroxide precipitate prepared in step (5) is dissolved in chemically pure hydrochloric acid with a density of 1.19 g / ml.

[0036] In this ratio, titanium (g): hydrochloric acid (mL) = 1:5 to 1:6.

[0037] In a preferred embodiment of the present invention, titanium (g): hydrochloric acid (mL) = 1:5.

[0038] If the required volume of the test bath is K liters, the calculated titanium content based on the upper limit is 5K grams, and the amount of hydrochloric acid required to precipitate 150K grams of titanium hydroxide is 25K milliliters.

[0039] The reaction mechanism in step (6) is: Ti(OH)4 + 2HCl = TiOC12 + 3H2O.

[0040] (7) After adding hydrochloric acid in step (6), the titanium hydroxide precipitate cannot be dissolved in a short time. It takes 1 hour for it to completely dissolve and generate titanium oxychloride.

[0041] Titanium oxychloride is an unstable substance and should not be left for too long. After the titanium oxychloride solution has clarified and been filtered, it should be added to the cadmium-titanium electroplating bath immediately.

[0042] Compared with existing technologies, this invention enables researchers to improve the success rate of titanium oxychloride solution preparation, minimize experimental costs and complexity, and shorten the production and research cycle. It also designs a detailed calculation method for consumables in the preparation of titanium oxychloride solution, eliminating the need for cumbersome calibration processes, clarifying the addition ratio of hydrochloric acid and the dissolution time of titanium hydroxide precipitate, and solving the problem of easy turbidity when titanium oxychloride solution is added to cadmium titanium plating bath, thereby improving the quality and solution stability of cadmium titanium plating bath.

[0043] The present invention will be explained below with reference to embodiments. Those skilled in the art will understand that the following embodiments are for illustrative purposes only and should not be considered as limiting the scope of the invention. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in the field or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially.

[0044] Example 1

[0045] (1) The volume of the test bath for cadmium-titanium electroplating is 1 liter (i.e., K=1). According to the composition of the bath described in aviation standard HB / Z107-86, the content of metallic titanium is 2g / L to 5g / L. The required content of metallic titanium is calculated to be 5g based on the upper limit.

[0046] (2) According to the navigation standard HB / Z107-86, 100g of industrial titanium oxysulfate contains 9-10g of titanium. Based on the required titanium content value, the consumption of titanium oxysulfate raw material is calculated to be 50g.

[0047] (3) Weigh 50g of industrial titanium oxysulfate into a beaker using an electronic balance, add 3.5 times the weight of deionized water, stir thoroughly, and let stand for 24 hours to obtain a colorless and transparent aqueous solution of titanium oxysulfate.

[0048] (4) At a rate of 35 ml / L, ammonia solution prepared by mixing concentrated ammonia solution with a mass concentration of 25% and water in a volume ratio of 1:1 is slowly added to the titanium oxysulfate aqueous solution filtered in step (3). The purpose of filtration is to ensure that there is no undissolved industrial titanium oxysulfate precipitate in the solution. When the pH is 7-8, the addition of ammonia solution is stopped. The temperature of the whole process is controlled at 0℃-10℃ to obtain titanium hydroxide precipitate.

[0049] (5) The titanium hydroxide precipitate prepared in step (4) is repeatedly washed with a large amount of deionized water more than 5 times by siphon method until no precipitation is produced when barium chloride solution is added to the water after washing, ensuring that sulfate ions are basically washed away. Then, it is filtered with dacron cloth and squeezed dry. During the squeezing process, the mass of the obtained titanium hydroxide precipitate is continuously weighed. When the titanium hydroxide precipitate reaches 150g, the squeezing is stopped.

[0050] (6) The 150g titanium hydroxide precipitate prepared in step (5) is immediately added to 25ml of hydrochloric acid (hydrochloric acid density is 1.19g / mL) for dissolution.

[0051] (7) After adding 25ml of hydrochloric acid in step (6), let it stand for 1 hour until the titanium oxychloride solution becomes clear and is filtered, and then immediately add it to the cadmium titanium electroplating bath.

[0052] The titanium oxychloride solution prepared in this embodiment was added to the cadmium-titanium plating bath, and the titanium content in the cadmium-titanium plating bath was measured to be 3.0 g / L, which meets the technical requirements of 2 g / L to 5 g / L for the titanium content of the cadmium-titanium plating bath specified in aviation standard HB / Z107-86.

[0053] Example 2

[0054] (1) The volume of the test bath for cadmium-titanium electroplating is 0.5 liters (i.e., K = 0.5). According to the composition of the bath described in aviation standard HB / Z107-86, the content of metallic titanium is 2 g / L to 5 g / L. The required content of metallic titanium is calculated to be 2.5 g based on the upper limit.

[0055] (2) According to the navigation standard HB / Z107-86, 100g of industrial titanium oxysulfate contains 9-10g of titanium. Based on the required titanium content value, the consumption of titanium oxysulfate raw material is calculated to be 25g.

[0056] (3) Weigh 25g of industrial titanium oxysulfate into a beaker using an electronic balance, add 3.5 times the weight of deionized water, stir thoroughly, and let stand for 24 hours to obtain a colorless and transparent aqueous solution of titanium oxysulfate.

[0057] (4) At a rate of 35 ml / L, ammonia solution prepared by mixing concentrated ammonia solution with a mass concentration of 25% and water in a volume ratio of 1:1 is slowly added to the titanium hydroxide aqueous solution filtered in step (3). When the pH is 7-8, the addition of ammonia solution is stopped. The temperature of the whole process is controlled at 0℃-10℃ to obtain titanium hydroxide precipitate.

[0058] (5) The titanium hydroxide precipitate prepared in step (4) is repeatedly washed with a large amount of deionized water more than 5 times by siphon method until no precipitation is produced when barium chloride solution is added to the water after washing, ensuring that sulfate ions are basically washed away. Then, it is filtered with dacron cloth and squeezed dry. During the squeezing process, the mass of the obtained titanium hydroxide precipitate is continuously weighed. When the titanium hydroxide precipitate reaches 75g, the squeezing is stopped.

[0059] (6) The 75g titanium hydroxide precipitate prepared in step (5) is immediately added to 12.5ml of hydrochloric acid (hydrochloric acid density is 1.19g / mL) to dissolve it.

[0060] (7) After adding 12.5 ml of hydrochloric acid in step (6), let it stand for 1 hour until the titanium oxychloride solution becomes clear and is filtered, and then immediately add it to the cadmium titanium electroplating bath.

[0061] The titanium oxychloride solution prepared in this embodiment was added to the cadmium-titanium plating bath, and the titanium content in the cadmium-titanium plating bath was measured to be 3.42 g / L, which meets the technical requirements of 2 g / L to 5 g / L for the titanium content of the cadmium-titanium plating bath specified in aviation standard HB / Z107-86.

Claims

1. A process for the preparation of a titanyl chloride solution for cadmium-titanium plating tests, characterized in that: It comprises the following steps: (1) Take titanyl sulfate, add 3.5 times the weight of water, stir evenly, and then place it to obtain a colorless and transparent titanyl sulfate aqueous solution; the amount of titanyl sulfate is calculated according to the volume of the bath solution for the cadmium-titanium plating test, and the content of metal titanium is 5 g / L; the titanyl sulfate is industrial titanyl sulfate, and the titanium content of 100 g of industrial titanyl sulfate is 9-10 g; (2) Add ammonia water to the titanyl sulfate aqueous solution at a rate of 35 mL / min to produce a titanium hydroxide precipitate, and stop adding ammonia water when the pH is 7-8; the ammonia water is prepared by mixing concentrated ammonia water with a mass concentration of 25% and water in a volume ratio of 1:1; (3) The titanium hydroxide precipitate prepared in step (2) is washed with water using the siphon method until no precipitate is produced when barium chloride solution is added to the washed water, and then filtered with a zhiqing cloth and squeezed dry to obtain the washed titanium hydroxide precipitate; the dryness of the titanium hydroxide precipitate is 30 g per 1 g of titanium based on the theoretical metal titanium content; (4) The washed titanium hydroxide precipitate in step (3) is dissolved by adding chemical pure hydrochloric acid, and after the titanium hydroxide precipitate is placed for 1 h and completely dissolved, impurities are removed by filtration to obtain a titanium oxychloride solution; the amount of hydrochloric acid added is calculated based on the theoretical metal titanium content, titanium (g): hydrochloric acid (mL) = 1:

5.

2. The method for preparing a cadmium titanium plating test titanyl chloride solution according to claim 1, characterized by: In step (2), the temperature of the whole process is controlled at 0-10℃.

3. The method for preparing a cadmium titanium plating test titanyl chloride solution according to claim 1, characterized by: The density of the hydrochloric acid is 1.19 g / mL.