Preparation method of TiO2 nano powder

Abstract

The invention discloses a preparation method of TiO2 nano powder, and relates to the technical field of chemical materials, the TiO2 nano powder comprises tetrabutyl titanate as a titanium source and ionic liquid as a stabilizer; the preparation method comprises the following steps: mixing tetrabutyl titanate and ionic liquid according to a molar ratio of 1: 2 at room temperature, uniformly stirring to obtain a mixed solution, putting the mixed solution into a hydrothermal reaction kettle, and hydrolyzing the tetrabutyl titanate to form TiO2 nanoparticles. A hydrolysis reaction is carried out in a hydrothermal reaction kettle, hydrolysis of tetrabutyl titanate is effectively promoted by controlling the reaction temperature and time, damage to equipment and increase of energy consumption caused by a high-temperature reaction are avoided, the ionic liquid is 1-butyl-3-methylimidazolium tetrafluoroborate, the effect of a stabilizer is achieved, and the reaction time is shortened. The size and the uniformity of the generated TiO2 nanoparticles are influenced by regulating and controlling the hydrolysis process of titanium ions; the T O < 2 > nano powder prepared by optimizing the preparation process has the advantages of high purity, uniform particle size distribution, good dispersity and the like.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of chemical materials, and in particular to a preparation method of TiO2 nano powder. BACKGROUND

[0002] In the field of nanotechnology, nano TiO2 is widely used in the fields of photocatalysis, solar cells, coatings and ceramics due to its unique physical and chemical properties, such as high catalytic activity, excellent photoelectric performance and good chemical stability. However, the preparation technology of nano TiO2 has been a research hotspot and difficulty, especially the preparation of nano powder with high purity and uniform particle size distribution.

[0003] In the prior art, the preparation method of nano TiO2 mainly includes gas phase method and liquid phase method. Although the gas phase method can obtain nano powder with high purity and uniform particle size distribution, the equipment is complex, the energy consumption is large, the cost is high, and large-scale production is difficult to realize. Although the liquid phase method is simple in equipment and low in cost, it is easy to cause uneven distribution of material concentration, uneven size and shape of products, and easy to cause particle aggregation during drying and calcination, affecting the dispersibility and use effect of the products.

[0004] Therefore, the application is proposed. SUMMARY

[0005] The application aims to provide a preparation method of TiO2 nano powder, which comprises tetrabutyl titanate as a titanium source and an ionic liquid as a stabilizer.

[0006] The preparation process comprises the following steps:

[0007] Step 1: at room temperature, tetrabutyl titanate and ionic liquid are mixed in a molar ratio of 1:2, stirred uniformly, and a mixed solution is obtained;

[0008] Step 2: the mixed solution is placed in a hydrothermal reaction kettle, tetrabutyl titanate is hydrolyzed, and TiO2 nanoparticles are formed;

[0009] Step 3: the hydrothermal reaction kettle is naturally cooled to room temperature to form a suspension, the suspension is centrifuged, and the precipitate is collected;

[0010] Step 4: the precipitate is washed with deionized water and anhydrous ethanol respectively to remove unreacted raw materials and impurities;

[0011] Step 5: the washed precipitate is placed in a drying box and dried at 80 DEG C for 12 hours, and the dried precipitate powder is calcined;

[0012] Step 6: the calcined precipitate powder is ground and collected by a collection device to obtain TiO2 nano powder.

[0013] Further, the ionic liquid is 1-butyl-3-methylimidazolium tetrafluoroborate.

[0014] Further, in step 1, stirring is performed using a magnetic stirrer until a uniform, transparent solution is formed.

[0015] Further, in step 2, the reaction temperature is 150-200℃, and the reaction time is 2-4h.

[0016] Further, in step 4, the precipitate is washed 3-5 times.

[0017] Further, in step 5, the calcination temperature is 500-600℃, and the calcination time is 2h.

[0018] Further, in step 2, during the hydrolysis process, the pH value is controlled between 6.5-7.5 to stabilize the precipitation of titanium ions.

[0019] Further, the TiO2 nanopowder obtained in step 6 is subjected to particle size analysis by a particle size analyzer, and the TiO2 nanopowder particle size distribution result is obtained.

[0020] Further, the TiO2 nanopowder is subjected to purity analysis using an X-ray diffractometer and an energy spectrometer, and the TiO2 nanopowder purity result is obtained.

[0021] Further, the TiO2 nanopowder is evaluated for photocatalytic performance using a rhodamine B degradation experiment, and the TiO2 nanopowder photocatalytic degradation ability is obtained.

[0022] By adopting the above technical solution, the present application has the following beneficial effects:

[0023] The ionic liquid is used as a stabilizer and a regulator, and by regulating the hydrolysis process of titanium ions, uniform generation and stable dispersion of TiO2 nanoparticles are achieved. This not only improves the purity of the product, but also ensures the uniformity of the particle size distribution.

[0024] The hydrolysis reaction is carried out in a hydrothermal reaction kettle, and by controlling the reaction temperature and time, the hydrolysis of tetrabutyl titanate is effectively promoted, and damage to the equipment and increase in energy consumption caused by high temperature reaction are avoided.

[0025] The present application only needs simple raw materials and equipment to realize large-scale production of nano-TiO2, and in addition, due to the avoidance of complex drying and calcination processes, the production cost is greatly reduced.

[0026] By optimizing the preparation process, the TiO2 nanopowder prepared by the present method has high purity, uniform particle size distribution, good dispersibility, etc., and can be widely applied in the fields of photocatalysis, solar cells, coatings and ceramics, etc.

[0027] A further detailed description of the specific embodiments of the present application is provided. DETAILED DESCRIPTION

[0028] The application provides a preparation method of TiO2 nanopowder, which comprises tetrabutyl titanate as a titanium source and an ionic liquid as a stabilizer. The high-purity tetrabutyl titanate helps to prepare high-purity TiO2 nanopowder. The ionic liquid has unique advantages in the preparation of nanomaterials due to its unique physical and chemical properties, such as high thermal stability, low volatility, good solubility and the like.

[0029] The preparation process comprises the following steps.

[0030] Step 1: At room temperature, tetrabutyl titanate and ionic liquid are mixed in a molar ratio of 1:2, stirred uniformly, and stirred for 30 min to obtain a mixed solution. The stirring ensures that the two are fully mixed to form a uniform solution, which directly affects the uniform dispersion of titanium ions and the rate of hydrolysis reaction.

[0031] Step 2: The mixed solution is placed in a hydrothermal reaction kettle to hydrolyze the tetrabutyl titanate. The reaction kettle provides a high-temperature and high-pressure environment, which is conducive to the hydrolysis of tetrabutyl titanate. The tetrabutyl titanate is hydrolyzed under the action of the ionic liquid to gradually form TiO2 nanoparticles. The ionic liquid plays the role of stabilizer and regulator in this process, so that the generated TiO2 nanoparticles are more uniform and dispersed. The hydrolysis reaction time is controlled within 2-4 h. Too long or too short reaction time will affect the morphology and performance of the nanoparticles.

[0032] Step 3: The hydrothermal reaction kettle is naturally cooled to room temperature to form a suspension. The centrifuge is used to centrifuge the suspension after reaction, and the precipitate is collected.

[0033] Step 4: The precipitate is washed with deionized water and anhydrous ethanol respectively to remove unreacted raw materials and impurities. Deionized water is used in the hydrolysis reaction and subsequent washing steps to ensure the purity of the final product.

[0034] Step 5: The washed precipitate is placed in a drying box and dried at 80℃ for 12 h. The calcination of the dried precipitate powder helps to remove water and other volatile substances in the precipitate. The calcination is carried out in an air atmosphere to improve the crystallinity and stability of TiO2 and improve its physical and chemical properties. The calcination temperature and time can be adjusted according to specific requirements. The calcination temperature is controlled within 500-600℃, and the time is 2 h.

[0035] Step 6: The calcined precipitate powder is ground, either manually or mechanically using a ball mill, to make the particle size more uniform, improve the uniformity of the nanoparticles, and collect the powder using a collection device, such as a filter or vacuum pump, to obtain TiO2 nanopowder. During the collection process, the powder should be protected from contamination and loss.

[0036] The use of ionic liquids as stabilizers and regulators allows for the uniform generation and stable dispersion of TiO2 nanoparticles by controlling the hydrolysis process of titanium ions. This not only improves the purity of the product but also ensures the uniformity of the particle size distribution.

[0037] The hydrolysis reaction is carried out in a hydrothermal reactor, which effectively promotes the hydrolysis of tetrabutyl titanate and avoids damage to the equipment and increased energy consumption at high temperatures. The ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate, not only acts as a stabilizer but also influences the size and uniformity of the generated TiO2 nanoparticles by regulating the hydrolysis process of titanium ions. By optimizing the preparation process, the TiO2 nanopowder prepared by this method has high purity, uniform particle size distribution, and good dispersion, making it suitable for applications in photocatalysis, solar cells, coatings, and ceramics.

[0038] In Step 1, a magnetic stirrer is used for stirring until a uniform, transparent solution is formed.

[0039] In Step 2, the reaction temperature is 150-200℃, and the reaction time is 2-4h.

[0040] In Step 4, the precipitate is washed 3-5 times.

[0041] In Step 5, the calcination temperature is 500-600℃, and the calcination time is 2h.

[0042] In Step 2, during the hydrolysis process, the pH value is controlled between 6.5-7.5 to allow the stable precipitation of titanium ions.

[0043] The TiO2 nanopowder obtained in Step 6 is analyzed for particle size using a particle size analyzer, and the particle size distribution of the TiO2 nanopowder is obtained.

[0044] The purity of the TiO2 nanopowder is analyzed using an X-ray diffractometer and an energy spectrometer, and the purity of the TiO2 nanopowder is obtained.

[0045] The photocatalytic performance of the TiO2 nanopowder is evaluated using a Rhodamine B degradation experiment, and the photocatalytic degradation ability of the TiO2 nanopowder is obtained.

[0046] Example 1 (basic conditions)

[0047] Tetrabutyl titanate and ionic liquid were weighed according to a molar ratio of 1:2, stirred uniformly at room temperature for 30 minutes, and then placed in a hydrothermal reactor for hydrolysis for 2 hours. After the hydrolysis, the mixture was naturally cooled to room temperature, centrifugally separated, and the precipitate was collected. The precipitate was washed with deionized water and anhydrous ethanol, dried at 80°C for 12 hours, and then calcined in air. The calcined precipitate powder was ground, and TiO2nanopowder was collected. The results showed that the TiO2nanopowder had a narrow particle size distribution, uniform particles, and good dispersibility.

[0048] Example 2 (adjusting the molar ratio)

[0049] Tetrabutyl titanate and ionic liquid were weighed according to a molar ratio of 1:3, stirred uniformly at room temperature for 30 minutes, and then placed in a hydrothermal reactor for hydrolysis for 2 hours. After the hydrolysis, the mixture was naturally cooled to room temperature, centrifugally separated, and the precipitate was collected. The precipitate was washed with deionized water and anhydrous ethanol, dried at 80°C for 12 hours, and then calcined in air. The calcined precipitate powder was ground, and TiO2nanopowder was collected. The results showed that the TiO2nanopowder had a further reduced particle size, but the yield was slightly decreased.

[0050] Example 3 (extending the hydrolysis time)

[0051] Tetrabutyl titanate and ionic liquid were weighed according to a molar ratio of 1:2, stirred uniformly at room temperature for 30 minutes, and then placed in a hydrothermal reactor for hydrolysis for 4 hours. After the hydrolysis, the mixture was naturally cooled to room temperature, centrifugally separated, and the precipitate was collected. The precipitate was washed with deionized water and anhydrous ethanol, dried at 80°C for 12 hours, and then calcined in air. The calcined precipitate powder was ground, and TiO2nanopowder was collected. The results showed that the TiO2nanopowder had a slightly reduced particle size, good dispersibility, but no significant advantage.

[0052] Example 4 (reducing the hydrolysis time)

[0053] Tetrabutyl titanate and ionic liquid were weighed according to a molar ratio of 1:2, stirred uniformly at room temperature for 30 minutes, and then placed in a hydrothermal reactor for hydrolysis for 1 hour. After the hydrolysis, the mixture was naturally cooled to room temperature, centrifugally separated, and the precipitate was collected. The precipitate was washed with deionized water and anhydrous ethanol, dried at 80°C for 12 hours, and then calcined in air. The calcined precipitate powder was ground, and TiO2nanopowder was collected. The results showed that the TiO2nanopowder had a wide particle size distribution, and some particles had agglomeration.

[0054] Example 5 (control without ionic liquid)

[0055] Only take tetrabutyl titanate, stir evenly at room temperature for 30 minutes, put the mixed solution into a hydrothermal reactor, hydrolysis time is 2h, after hydrolysis, naturally cool to room temperature, centrifugal separation and collect the precipitate, wash the precipitate with deionized water and anhydrous ethanol, dry the precipitate at 80℃ for 12 hours, then calcine in air, grind the calcined precipitate powder, collect TiO2nanopowder, result: TiO2nanopowder particle size distribution is wide, and agglomeration phenomenon is obvious.

[0056] Specifically as follows table 1:

[0057]

[0058] Table 1

[0059] It should be noted that using ionic liquid as stabilizer and regulator can significantly affect the particle size distribution and dispersibility of TiO2nanopowder, the presence of ionic liquid makes TiO2nanoparticles more uniform and good dispersibility, increasing the molar ratio of ionic liquid to tetrabutyl titanate can lead to further reduction of TiO2nanopowder particle size, but too high proportion of ionic liquid will lead to slight decrease in yield, hydrolysis time also has certain influence on the particle size and dispersibility of TiO2nanopowder, appropriate extension of hydrolysis time can make the particle size slightly smaller and the dispersibility remain good, but there is no significant advantage, on the contrary, reducing the hydrolysis time will lead to wide particle size distribution and agglomeration phenomenon, in the absence of ionic liquid, the particle size distribution of TiO2nanopowder is wide, and there is obvious agglomeration phenomenon, which further proves the importance of ionic liquid in the preparation process, considering the particle size, dispersibility and yield and other factors, the basic condition (molar ratio of ionic liquid to tetrabutyl titanate 1:2, hydrolysis time 2h) is a relatively ideal preparation condition, by adjusting the molar ratio of ionic liquid to tetrabutyl titanate and hydrolysis time, the particle size and dispersibility of TiO2nanopowder can be controlled to meet the needs of different applications.

[0060] Put the hydrolysis reaction into a hydrothermal reactor, control the reaction temperature and time to effectively promote the hydrolysis of tetrabutyl titanate, and avoid damage to equipment and increase of energy consumption caused by high temperature reaction, the ionic liquid is 1-butyl-3-methylimidazolium tetrafluoroborate, which not only plays the role of stabilizer, but also affects the size and uniformity of TiO2nanoparticles generated by regulating the hydrolysis process of titanium ions; by optimizing the preparation process, the TiO2nanopowder prepared by this method has the advantages of high purity, uniform particle size distribution and good dispersibility, and can be widely used in the fields of photocatalysis, solar cells, coatings and ceramics.

[0061] The embodiments are only illustrative of the application and are not intended to limit the application. Those skilled in the art can make modifications to the embodiments without creative contribution after reading the specification, and the modifications are within the protection scope of the application and are protected by the patent law.

Claims

1. A method for preparing TiO2 nanopowder, characterized in that, This includes tetrabutyl titanate as a titanium source and ionic liquids as stabilizers; The preparation process includes the following steps: Step 1: At room temperature, mix tetrabutyl titanate and ionic liquid at a molar ratio of 1:2 and stir until homogeneous to obtain a mixed solution; Step 2: Place the mixed solution in a hydrothermal reactor to hydrolyze tetrabutyl titanate to form TiO2 nanoparticles; Step 3: Allow the hydrothermal reactor to cool naturally to room temperature to form a suspension. Centrifuge the suspension and collect the precipitate. Step 4: Wash the precipitate with deionized water and anhydrous ethanol respectively to remove unreacted raw materials and impurities; Step 5: Place the washed precipitate in a drying oven and dry it at 80°C for 12 hours. Then, calcine the dried precipitate powder. Step 6: Grind the calcined precipitate powder and collect it using a collection device to obtain TiO2 nanoparticles.

2. The method for preparing TiO2 nanopowder according to claim 1, characterized in that, The ionic liquid is 1-butyl-3-methylimidazolium tetrafluoroborate.

3. The method for preparing TiO2 nanopowder according to claim 2, characterized in that, In step 1, a magnetic stirrer is used to stir the solution until a uniform, transparent solution is formed.

4. The method for preparing TiO2 nanopowder according to claim 3, characterized in that, In step 2, the reaction temperature is 150-200℃ and the reaction time is 2-4 hours.

5. The method for preparing TiO2 nanopowder according to claim 4, characterized in that, In step 4, the precipitate is washed 3-5 times.

6. The method for preparing TiO2 nanopowder according to claim 5, characterized in that, In step 5, the calcination temperature is 500-600℃ and the calcination time is 2 hours.

7. The method for preparing TiO2 nanopowder according to claim 3, characterized in that, In step 2, during the hydrolysis process, the pH value is controlled between 6.5 and 7.5 to ensure the stable precipitation of titanium ions.

8. The method for preparing TiO2 nanopowder according to claim 6, characterized in that, The TiO2 nanopowder obtained in step 6 was subjected to particle size analysis using a particle size analyzer to obtain the particle size distribution results of the TiO2 nanopowder.

9. The method for preparing TiO2 nanopowder according to claim 8, characterized in that, The purity of TiO2 nanopowder was analyzed using X-ray diffraction and energy dispersive spectroscopy, and the purity results of TiO2 nanopowder were obtained.

10. The method for preparing TiO2 nanopowder according to claim 9, characterized in that, The photocatalytic performance of TiO2 nanoparticles was evaluated using a Rhodamine B degradation experiment, and the photocatalytic degradation ability of TiO2 nanoparticles was obtained.

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