Method for preparing titanium dioxide by template method
Through the template method, the flaky substrate is hydrolyzed and calcined with titanium dichloride solution under acidic conditions, which solves the problems of environmental pollution and technical difficulty in titanium dioxide production, and achieves the effect of improving particle size uniformity and simplifying the production process.
Patent Information
- Application Number
- CN202511054287.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-30
- Publication Date
- 2025-09-12
AI Technical Summary
Existing titanium dioxide production methods have serious environmental pollution and high technical difficulty. There is an urgent need to explore simple, easy, safe and environmentally friendly preparation methods.
The template method is adopted, and a flaky substrate is used as a carrier. It is hydrolyzed with a titanium dichloride solution under acidic conditions to generate titanic acid. Titanium dioxide is prepared by ultrasonic treatment and calcination. The reaction conditions such as temperature, pH value, droplet acceleration rate, etc. are controlled to ensure uniform deposition and separation, and finally spray calcination is carried out.
The uniformity of the particle size of the titanium dioxide product is improved, the production process is simplified, the risk of environmental pollution is reduced, and a safe and environmentally friendly preparation process is achieved.
Smart Images
Figure CN120622531A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of titanium dioxide pigments, in particular to a method for preparing titanium dioxide using a template method. Background Art
[0002] Titanium dioxide (Titanium dioxide) is an important inorganic functional material with excellent optical properties, chemical stability, and photocatalytic activity. It is widely used in coatings, plastics, cosmetics, photocatalysis, solar cells, and other fields. Traditional industrial production methods for titanium dioxide mainly include the sulfuric acid method and the chlorination method. The sulfuric acid method uses ilmenite as the raw material and decomposes it with sulfuric acid to produce titanium dioxide, which is relatively polluting to the environment. The chlorination method uses rutile or high-titanium slag as the raw material, chlorinating it to produce titanium tetrachloride, which is then oxidized at high temperature to produce titanium dioxide. This method is technically difficult.
[0003] Therefore, there is an urgent need to explore simple, easy, safe and environmentally friendly methods to prepare titanium dioxide.
[0004] In view of this, the present invention is proposed. Summary of the Invention
[0005] The present invention aims to provide a method for preparing titanium dioxide by a template method, aiming to provide a simple, easy, safe and environmentally friendly method for preparing titanium dioxide.
[0006] The present invention is achieved in that:
[0007] In a first aspect, the present invention provides a method for preparing titanium dioxide by a template method, comprising:
[0008] Mixing the flaky substrate and water and adjusting the pH to 1.0-2.5 to obtain an acidic mixed solution;
[0009] The acidic mixed liquid and the titanium dichloride solution are mixed and reacted, and then the flaky substrate is separated to obtain a reaction liquid;
[0010] The reaction solution is calcined.
[0011] In an optional embodiment, during the mixing reaction with the titanium dichloride solution, the titanium dichloride solution is added dropwise, and the reaction temperature is controlled to be 80°C-95°C.
[0012] In an optional embodiment, the concentration of the titanium oxychloride solution is 140 g / L-180 g / L based on the titanium dioxide content;
[0013] And / or, the dropping rate of the titanium oxychloride solution is 1 mL / min-3 mL / min.
[0014] In an optional embodiment, the concentration of the sheet substrate is 80 g / L-120 g / L by adjusting the amount of water;
[0015] And / or, the volume ratio of the acidic mixed solution to the titanium dichloride solution is (1-3):1.
[0016] In an optional embodiment, the material of the flaky substrate is selected from at least one of synthetic mica, glass, aluminum oxide and silicon dioxide.
[0017] In an optional embodiment, the process of separating the flaky substrate comprises: subjecting the reacted system to ultrasonic treatment, followed by filtering.
[0018] In an optional embodiment, the ultrasonic treatment time is controlled to be 2h-3h, and the ultrasonic power is 500W-1000W;
[0019] And / or, the separated sheet-like substrate is recycled.
[0020] In an optional embodiment, a surfactant is added during the ultrasonic treatment, wherein the surfactant is selected from at least one of polyvinyl pyrrolidone, octadecyl oleylamine and polyethylene glycol (molecular weight 1000-10000);
[0021] The mass ratio of the added amount of the surfactant to the total amount of the system after the reaction is (0.01-0.10):100.
[0022] In an optional embodiment, the reaction solution is spray calcined.
[0023] In an optional embodiment, during the spray calcination process, ultrasonic or pressure atomization is used to control the droplet size to 5 μm-10 μm;
[0024] And / or, the calcination temperature is controlled to be 400° C.-500° C., and the calcination time is controlled to be 60 min-120 min.
[0025] The present invention has the following beneficial effects: A flaky substrate is used as a carrier, and titanium dichloride is used as a raw material, which is first hydrolyzed under acidic conditions to produce metatitanic acid, which is then uniformly deposited on the carrier. Demolding is achieved after ultrasonic treatment, and the flaky substrate is separated, followed by calcination to produce titanium dioxide with uniform particle size. The improved template-based titanium dioxide preparation method of the present invention can significantly improve the particle size uniformity of the titanium dioxide product, and the production process is simple and easy. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.
[0027] Figure 1 A process flow chart provided for an embodiment of the present invention;
[0028] Figure 2 This is an electron microscope image of the titanium dioxide product obtained in Example 1. DETAILED DESCRIPTION
[0029] To make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer are used. Where the manufacturer of the reagents or instruments is not specified, all are conventional products that can be purchased commercially.
[0030] like Figure 1 As shown, the embodiment of the present invention provides a method for preparing titanium dioxide by a template method, using a flaky substrate as a carrier and titanium dichloride as a raw material for preparation, and the specific steps are as follows:
[0031] S1. Hydrolysis of titanium dichloride
[0032] The flaky substrate and water are mixed, the temperature is raised to the hydrolysis reaction temperature, and the pH value is adjusted to 1.0-2.5 to obtain an acidic mixed solution; the acidic mixed solution is mixed with a titanium dichloride solution to react, so that the titanium dichloride is hydrolyzed under acidic conditions to obtain metatitanic acid.
[0033] In actual operation, the flaky substrate and water can be added sequentially to a stirred reactor, the temperature then raised to the hydrolysis reaction temperature, and the pH adjusted to 1.0-2.5 to meet the requirements of the hydrolysis reaction. Specifically, after adjusting the pH with 10% dilute hydrochloric acid, the pH of the system can be 1.0, 1.5, 2.0, 2.5, etc., or any value between the above adjacent values.
[0034] In some embodiments, the material of the flaky substrate is selected from at least one of synthetic mica, glass, aluminum oxide, and silicon dioxide, and the flaky substrate may be any one or more of the above. The amount of water used is adjusted so that the concentration of the flaky substrate after mixing with water is 80 g / L-120 g / L, such as 80 g / L, 90 g / L, 100 g / L, 110 g / L, 120 g / L, etc., or any value between the above values.
[0035] In some embodiments, during the mixing reaction with the titanium dichloride solution, the titanium dichloride solution is added dropwise, and the reaction temperature is controlled to be 80°C-95°C, such as 80°C, 85°C, 90°C, 95°C, etc., or any value between the above adjacent values. Under these reaction temperature conditions, titanium dichloride can be more fully hydrolyzed, thereby improving the utilization rate of raw materials.
[0036] Furthermore, based on the titanium dioxide content, the concentration of the titanium dichloride aqueous solution is 140 g / L-180 g / L, such as 140 g / L, 150 g / L, 160 g / L, 170 g / L, 180 g / L, etc., or any value between the above adjacent values. The dripping rate of the titanium dichloride solution is 1 mL / min-3 mL / min, such as 1.0 mL / min, 1.5 mL / min, 2.0 mL / min, 2.5 mL / min, 3.0 mL / min, etc., or any value between the above adjacent values. The volume ratio of the acidic mixed solution to the titanium dichloride solution is (1-3):1, such as 1.0:1, 1.5:1, 2.0:1, 2.5:1, 3.0:1, etc., or any value between the above adjacent values. By regulating the concentration, volume and drop rate of the titanium dichloride aqueous solution, the reaction rate can be better controlled, the hydrolysis reaction rate can be made more appropriate, and the titanium dichloride can be deposited more evenly on the flaky substrate during hydrolysis.
[0037] S2. Separation of sheet substrate
[0038] After the titanium dichloride solution is added dropwise, the flaky substrate is separated to obtain a reaction solution (ie, a metatitanic acid solution) for use in a subsequent calcination process.
[0039] The method for separating the flaky substrates is not limited. In some embodiments, the process of separating the flaky substrates includes: subjecting the post-reaction system to ultrasonic treatment, so that the particles on the flaky substrates can be dispersed more quickly by ultrasonic separation, and then filtering to remove larger flaky substrates. The separated flaky substrates are recycled.
[0040] In some embodiments, during the ultrasonic treatment process, the ultrasonic treatment time is controlled to be 2 hours to 3 hours, such as 2.0 hours, 2.3 hours, 2.5 hours, 2.8 hours, 3.0 hours, etc., or any value between the above adjacent values. The ultrasonic power is 500W to 1000W, such as 500W, 600W, 700W, 800W, 900W, 1000W, etc. By regulating the ultrasonic treatment power and time, the particles deposited on the sheet substrate are dispersed, thereby improving the product yield.
[0041] In some embodiments, in order to fully scatter the particles deposited on the sheet substrate, a surfactant is added during the ultrasonic treatment process. By adding the surfactant, it is adsorbed on the surface of the nanoparticles, which helps the nanoparticles to be dispersed in the solution system and avoid agglomeration. The surfactant is selected from at least one of polyvinyl pyrrolidone, octadecylamine and polyethylene glycol (molecular weight 1000-10000), and the surfactant can be any one or more of the above. The mass ratio of the amount of surfactant added to the total amount of the system after the reaction is (0.01-0.10):100, such as 0.01:100, 0.03:100, 0.05:100, 0.08:100, 0.10:100, etc. The amount of the surfactant is preferably within the above range. Too little is not conducive to the dispersion of the particles, and too much will increase the cost.
[0042] S3. Calcination
[0043] The reaction solution is calcined to obtain nano titanium dioxide particles with an average particle size of 30 μm to 40 μm.
[0044] In some embodiments, the calcination operation is performed by spray calcination, which is beneficial for obtaining nano-titanium dioxide particles with more uniform particle size and recovering the dilute hydrochloric acid produced by the thermal decomposition of the titanium oxychloride solution.
[0045] Furthermore, during the spray calcination process, ultrasonic or pressure atomization is used to control the droplet size to 5 μm-10 μm (e.g., 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, etc.). The droplet size refers to the maximum distance between two points on the droplet. If the droplet is circular, the size is the diameter. The calcination temperature is controlled to be 400°C-500°C (e.g., 400°C, 430°C, 450°C, 480°C, 500°C, etc.), and the calcination time is 60 min-120 min (e.g., 60 min, 80 min, 100 min, 120 min, etc.). By regulating the calcination temperature and time, the metatitanic acid is fully converted into the titanium dioxide product.
[0046] The features and performance of the present invention are further described in detail below with reference to the embodiments.
[0047] Example 1
[0048] This embodiment provides a method for preparing titanium dioxide using a template method, the steps are as follows:
[0049] (1) Hydrolysis of titanium dichloride
[0050] In a stirred reactor, 200 g of a flaky substrate (commercially available synthetic mica with an average thickness of 0.5 μm and a size of 10-60 μm) and 2 L of deionized water were added in sequence, the temperature was raised to 90°C, the pH value was adjusted to 1.0-2.5, and 1000 mL of titanium dichloride solution (containing 160 g / L of titanium dioxide) was added at a rate of 2 mL / min for reaction.
[0051] (2) Separation of sheet substrate
[0052] After the titanium dichloride solution was added, the solution was transferred to an ultrasonic device and a surfactant (octadecylamine, with a mass ratio of 0.01:100 to the total volume of the system after the reaction) was added. Ultrasonication was performed for 2.5 hours at a power of 500 W. The flaky substrate was then separated by filtration and recycled.
[0053] (3) Calcination
[0054] The solution obtained in step (2) is spray-calcined to obtain nano-titanium dioxide. Pressure atomization is used, the droplet size is controlled to be 5 μm-10 μm, the calcination temperature is controlled to be 400° C., and the calcination time is controlled to be 60 minutes.
[0055] After testing, the average particle size of the nano titanium dioxide prepared in this embodiment is 30 μm. The electron microscope image of the nano titanium dioxide obtained in Example 1 is as follows: Figure 2 As shown, it can be seen that the nano-titanium dioxide particles are uniform and small in size.
[0056] Example 2
[0057] The only difference from Example 1 is that the reaction temperature in step (1) is 80°C.
[0058] The results showed that the average particle size of the nano-titanium dioxide prepared in this example was 35 μm.
[0059] Example 3
[0060] The only difference from Example 1 is that the reaction temperature in step (1) is 95°C.
[0061] The results showed that the average particle size of the nano-titanium dioxide prepared in this example was 40 μm.
[0062] Example 4
[0063] The only difference from Example 1 is that the titanium dioxide content in the titanium oxychloride solution in step (1) is 140 g / L.
[0064] The results showed that the average particle size of the nano-titanium dioxide prepared in this example was 40 μm.
[0065] Example 5
[0066] The only difference from Example 1 is that the titanium dioxide content in the titanium oxychloride solution in step (1) is 180 g / L.
[0067] The results showed that the average particle size of the nano-titanium dioxide prepared in this example was 32 μm.
[0068] Example 6
[0069] The only difference from Example 1 is that the amount of the sheet substrate used in step (1) is 160 g.
[0070] The results showed that the average particle size of the nano-titanium dioxide prepared in this example was 36 μm.
[0071] Example 7
[0072] The only difference from Example 1 is that the amount of the sheet substrate used in step (1) is 240 g.
[0073] The results showed that the average particle size of the nano-titanium dioxide prepared in this example was 38 μm.
[0074] Example 8
[0075] The only difference from Example 1 is that the amount of deionized water used in step (1) is 1 L.
[0076] The results showed that the average particle size of the nano-titanium dioxide prepared in this example was 36 μm.
[0077] Example 9
[0078] The only difference from Example 1 is that the amount of deionized water used in step (1) is 3 L.
[0079] The results showed that the average particle size of the nano-titanium dioxide prepared in this example was 30 μm.
[0080] Example 10
[0081] The only difference from Example 1 is that the sheet substrate is glass, and the thickness, shape and size are the same as in Example 1.
[0082] The results showed that the average particle size of the nano-titanium dioxide prepared in this example was 34 μm.
[0083] Example 11
[0084] The only difference from Example 1 is that the sheet substrate is an aluminum oxide sheet with the same thickness, shape and size as Example 1.
[0085] The results showed that the average particle size of the nano-titanium dioxide prepared in this example was 35 μm.
[0086] Example 12
[0087] The only difference from Example 1 is that the sheet substrate is a silicon dioxide sheet with the same thickness, shape and size as Example 1.
[0088] The results showed that the average particle size of the nano-titanium dioxide prepared in this example was 33 μm.
[0089] Comparative Example 1
[0090] The only difference from Example 1 is that no flake substrate is added.
[0091] The results showed that the average particle size of the nano-titanium dioxide prepared in this comparative example was 100 μm.
[0092] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.
Claims
1. A method for preparing titanium dioxide by a template method, characterized in that: include: Mixing the flaky substrate and water and adjusting the pH to 1.0-2.5 to obtain an acidic mixed solution; mixing the acidic mixed solution with a titanium dichloride solution to react, and then separating the sheet substrate to obtain a reaction solution; The reaction solution is calcined.
2. The method according to claim 1, characterized in that During the mixing reaction with the titanium dichloride solution, the titanium dichloride solution is added dropwise, and the reaction temperature is controlled to be 80° C.-95° C.
3. The method according to claim 2, characterized in that The concentration of the titanium dichloride solution is 140 g / L-180 g / L in terms of titanium dioxide content; And / or, the titanyl dichloride solution has a dropping rate of 1 mL / min-3 mL / min.
4. The method according to claim 3, characterized in that By adjusting the amount of water, the concentration of the flake substrate is 80g / L-120g / L; And / or, the volume ratio of the acidic mixed solution to the titanium dichloride solution is (1-3):
1.
5. The method according to any one of claims 1 to 4, characterized in that The material of the flaky substrate is selected from at least one of synthetic mica, glass, aluminum oxide and silicon dioxide.
6. The method according to claim 1, characterized in that The process of separating the sheet-like substrate comprises: subjecting the reacted system to ultrasonic treatment and then filtering.
7. The method according to claim 6, characterized in that The ultrasonic treatment time is controlled to be 2h-3h and the ultrasonic power is 500W-1000W; And / or, the separated sheet-like substrate is recycled.
8. The method according to claim 7, characterized in that adding a surfactant during the ultrasonic treatment, wherein the surfactant is selected from at least one of polyvinyl pyrrolidone, octadecyl oleylamine and polyethylene glycol; The mass ratio of the added amount of the surfactant to the total amount of the system after the reaction is (0.01-0.10):
100.
9. The method according to claim 1, characterized in that The reaction solution is spray-calcined.
10. The method according to claim 9, characterized in that During the spray calcination process, ultrasonic or pressure atomization is used to control the droplet size to 5 μm-10 μm; And / or, the calcination temperature is controlled to be 400° C.-500° C., and the calcination time is controlled to be 60 min-120 min.