WO2022078015A1 - Method for preparing titanium dioxide powder in different morphologies by using solid-phase process - Google Patents

Abstract

Disclosed is a method for preparing titanium dioxide powder in different morphologies by using a solid-phase process. The method comprises the following steps: S1. weighing titanyl sulfate solid and sodium carbonate solid in a ceramic mortar; S2. adding a different surfactant to the ceramic mortar; S3. adding a small amount of water to the solid mixture and continuing to grind same; S4. transferring the mixture into a centrifuge tube and carrying out centrifugal separation on a centrifugal machine; and after centrifugal separation is completed, pouring out a supernatant, adding water, stirring same for 2-5 minutes by using a glass rod, carrying out centrifugation again, and repeating centrifugation in this manner five times; S5. putting the solid, which has been washed with water, into a drying oven at 110℃ for drying for 1 h; S6. putting the dried powder into a muffle furnace for calcination; and S7. putting the calcined sample into a sample bag. In the present invention, the solid-phase synthesis method for the titanium dioxide powder is simple in terms of process conditions, low in terms of cost and equipment requirements, and is environmentally friendly, has a small particle size of titanium dioxide, a high yield, and continuous and adjustable operation procedures, and facilitates industrial production.

Description

A method for preparing titanium dioxide powders with different morphologies by solid-phase method technical field

The invention relates to a method for preparing titanium dioxide powder, in particular to a method for preparing titanium dioxide powder with different shapes by a solid phase method.

Background technique

Titanium dioxide (TiO ₂ ) is widely used in the degradation of organic wastewater, the reduction of heavy metal ions, air purification, sterilization, anti-fog and many other fields due to its high photocatalytic activity, good stability, non-toxicity to human body, and low price.

The preparation methods of nano titanium dioxide mainly include gas phase method, liquid phase method and solid phase method [Chen X B, Mao S S. Titanium dioxide nanomaterials: synthesis, properties, modifications, and applications, Chem. Rev., 2007, 107(7): 2891-2959]. The gas phase method is generally to first vaporize the reaction precursor by specific means to make it undergo physical or chemical changes under gas phase conditions, and then nucleate and grow during the cooling process, and finally form nano-titanium dioxide [Akurati K K, VitalA, Klotz U E , et al. Synthesis of non-aggregated titania nanoparticles in atmospheric pressure diffusion flames, Powder Technol., 2006, 165(2):73-82]. The prepared ultrafine particles have the characteristics of high purity, fine particle size, strong chemical activity, high surface activity, good monodispersity, and few aggregated particles. The disadvantage is that the process temperature is high, the requirements for equipment materials are strict, the control requirements for process parameters are precise, and the product cost is high. The liquid-phase method is currently the most important and most researched method in the field of preparation of nano-TiO2 particles in the world. , Liu P G, Cheng X S, et al. Effect of surfactants on synthesis of TiO ₂ nano-particles by homogeneous precipitation method, Powder Technol., 2008, 188(1): 52-54], the liquid phase method can be subdivided into micro Emulsion method, hydrothermal method/solvothermal method, precipitation method and sol-gel method, etc. A microemulsion is usually a transparent, isotropic thermodynamic composition consisting of four components: water (or electrolyte solution), oil (usually hydrocarbons), surfactants, and cosurfactants (usually alcohols). Stable system [Kim K D, Kim S H, Kim H T. Applying the Taguchi method to the optimization for the synthesis of TiO ₂ nanoparticles by hydrolysis of TEOT in micelles, Coll. Surf. A., 2005, 254(1-3): 99-105]. Among them, the homogeneous monodisperse microemulsion is widely used in the preparation of nanomaterials because the dispersed phase is uniform nanoscale droplets. According to their disperse phase and continuous phase, they can be divided into water-in-oil (W/O) and oil-in-water (O/W) types. Sol-gel method [Neppolian B, Wang Q, Jung H, et al. Ultrasonic-assisted sol-gel method of preparation of TiO ₂ nano-particles: Characterization, properties and 4-chlorophenol removal application, Ultrason Sonochem., 2008, 15 (4): 649-658] The preparation of nano-titanium dioxide is usually carried out at room temperature, the equipment is simple, the investment is low, and it has the advantages of high purity, good chemical uniformity, large activity, small particles, and easy to disperse and suspend in an aqueous solution; but at the same time It also has the disadvantages of poor sinterability, large drying shrinkage and long preparation cycle. The solvothermal method is a new method for the preparation of titanium dioxide based on the hydrothermal method [Li G H,Gray K A.Preparation of mixed-phase titanium dioxide nanocomposites via olvothermal processing,Chem.Mater.,2007,19(5) :1143-1146], the preparation principle is similar to that of the hydrothermal method, and the difference from the hydrothermal method is that the water in the hydrothermal method is replaced with an organic solvent or a non-aqueous solvent. At present, most of the solvothermal synthesis of titanium dioxide is still in the stage of theoretical exploration or laboratory exploration, and more in-depth research is needed on the selection of organic solvents and the optimization of process conditions. Precipitation method is a relatively simple method to prepare nano-TiO ₂ [Wang H, Liu P G, Cheng X S, et al. Effect of surfactants on synthesis of TiO ₂ nano-particles by homogeneous precipitation method, Powder Technol., 2008, 188(1) : 52-54], direct precipitation usually takes inorganic titanium salt as raw material, directly adds precipitant such as ammonia water to promote its hydrolysis reaction to generate insoluble hydroxide, then separates the precipitation, and obtains TiO ₂ particles after washing, drying and calcining . However, because the obtained precipitate is generally a colloid, it is difficult to wash and filter; and the product is easy to introduce impurities, so it is rarely used now. The uniform precipitation method uses chemical reactions to generate uniform and slow crystalline ions in the solution. As long as the speed of precipitation is well controlled, the phenomenon of uneven concentration can be avoided. The product has high purity, uniform particle size, and is easy to wash. It effectively solves the problem of impurities in the precipitation caused by the high local concentration in the direct precipitation method. The solid phase method is to prepare TiO ₂ powder by the change from solid phase to solid phase, usually by grinding and pulverizing solid materials by mechanical force [Gajovic A, Furic K, Tomasic N, et al.Mechanochemical preparation of nanocrystalline TiO ₂ powders and their behavior at high temperatures, J. Alloys Compd., 2005, 398(1-2): 188-199]. The solid-phase method has the advantages of simple process, low cost, high yield, and can be mass-produced, but the disadvantages such as easy introduction of impurities in the process limit the development of the solid-phase method. In recent years, with the improvement of mechanical technology, solid-phase method has gradually attracted everyone's attention in the field of preparation of nanomaterials.

A method for preparing nano-titanium dioxide powders with different morphologies by a solid-phase method is to provide an alkaline environment by hydrolysis of sodium carbonate, and to obtain nano-products through a chemical reaction with titanium oxysulfate and calcination and other processes. The addition has a regulating effect on the particle size and morphology of titanium dioxide. The innovation lies in the use of solid-phase method to control the chemical reaction, which is simple, fast and easy to operate; at the same time, the orthogonal experimental design is used to systematically study the effects of water dosage, surfactant dosage, surfactant type and calcination temperature on TiO2 crystal types and particles. However, the general method for synthesizing titanium dioxide is the liquid phase method, and most literatures do not study the effect of different surfactant types on the crystal form and morphology of titanium dioxide in detail. Therefore, this method can provide a new theoretical basis and practical reference for titanium dioxide through the use of surfactants through the solid-phase method.

There are many published patents for preparing titanium dioxide, including: a method for preparing high-efficiency nano-titanium dioxide photocatalyst at room temperature (publication number: CN107519852A), a preparation method for sea urchin-like rutile-type nano-titanium oxide (publication number: CN105439197A), a A kind of nanometer titanium dioxide modified by liquid phase silicon deposition (publication number: CN105131655B), a preparation method of lithiated nanometer titanium oxide and its application (publication number: CN101475213A), etc., but the use of solid-phase method to synthesize titanium dioxide powder is rare. relevant literature reports.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a method for preparing titanium dioxide powders with different shapes by a solid-phase method, the method has simple process conditions, low cost, low requirements for equipment, environmental protection, and large output of titanium dioxide powders, and the operation procedure is continuous. Adjustable and easy to control the experimental process, so it is easy for industrial production; different crystal forms (anatase, anatase and rutile can be prepared by adjusting the experimental parameters (water amount, surfactant amount, surfactant type and calcination temperature) Mixed crystal form, rutile type) titanium dioxide with different morphologies (random, rod-shaped and random, rod-shaped and cubic, cubic); the relatively simple solid-phase grinding is used, which is significantly different from the preparation environment of the general liquid-phase method. Simple and fast preparation of titanium dioxide.

The object of the present invention can be realized through the following technical solutions:

A method for preparing titanium dioxide powders with different shapes by a solid-phase method, the method comprises the following steps:

S1: take by weighing titanyl sulfate solid and sodium carbonate solid in a ceramic mortar, and the mol ratio of titanyl sulfate solid and sodium carbonate solid is 1:1;

S2: add different surfactants in a ceramic mortar and grind for 3min, wherein the cationic surfactant is cetyltrimethylammonium bromide, the anionic surfactant is sodium dodecylbenzenesulfonate, nonionic The surfactant is polyethylene glycol with a molecular weight of 10000, and the proportion of the surfactant to the total amount of the reactants is 2%-6%;

S3: the water of 3mL-7mL is added in solid mixture, continue to grind 60min;

S4: After grinding, transfer the mixture to a centrifuge tube, centrifuge on a centrifuge, pour off the supernatant after finishing, add water, stir with a glass rod for 2min-5min, centrifuge again, repeat the centrifugation five times, complete five secondary washing process;

S5: the solid after washing is placed in an oven at 110 ° C and dried for 1 h;

S6: put the dried powder into a muffle furnace for calcination for 1.5h, and the calcination temperature range is 500°C-900°C;

S7: Finally, the calcined sample is put into a sample bag for use.

Further, the sodium carbonate in the S1 is anhydrous sodium carbonate or hydrated sodium carbonate.

Further, the surfactant in S2 is a cationic surfactant, an anionic surfactant or a nonionic surfactant.

Further, the cationic surfactant cetyl trimethyl ammonium bromide, the anionic surfactant sodium dodecyl benzene sulfonate, the non-ionic surfactant polyethylene glycol with a molecular weight of 10000, the surfactant The proportion of the total amount of the reactants is 2%-6%.

Further, the consumption of water in the S3 is 3mL-7mL, and the grinding time is 30min-90min.

Further, the number of times of washing in S4 is 3 to 7 times.

Further, the drying temperature in S5 is 100°C-120°C, and the drying time is 0.5h-2h.

Further, the calcination temperature in the S6 is 500°C-900°C, and the calcination time is 1h-2h.

Beneficial effects of the present invention:

1. The method for preparing titanium dioxide powder of the present invention has simple process conditions, low cost, low requirements for equipment, environmental protection and large output of titanium dioxide powder, and the operation procedure is continuously adjustable, and it is easy to control the experimental process, so it is easy to industrialized production;

2. The method for preparing titanium dioxide powder of the present invention prepares different crystal forms (anatase type, anatase and rutile mixed crystal form, rutile) titanium dioxide with different morphologies (random, rod-like and random, rod-like and cubic, cubic);

3. The method for preparing titanium dioxide powder of the present invention adopts relatively simple solid phase grinding, which is significantly different from the preparation environment of the general liquid phase method, and titanium dioxide is prepared simply and quickly.

Description of drawings

The present invention will be further described below in conjunction with the accompanying drawings.

Fig. 1 is X-ray diffraction (XRD) pattern of the present invention;

Fig. 2 is the scanning electron microscope (SEM) figure of No. 1 titanium dioxide of the present invention;

Fig. 3 is the SEM image of No. 2 titanium dioxide of the present invention;

Fig. 4 is the SEM image of No. 3 titanium dioxide of the present invention;

Fig. 5 is the SEM image of No. 4 titanium dioxide of the present invention;

Fig. 6 is the SEM image of No. 5 titanium dioxide of the present invention;

Fig. 7 is the SEM image of No. 6 titanium dioxide of the present invention;

Fig. 8 is the SEM image of No. 7 titanium dioxide of the present invention;

Fig. 9 is the SEM image of No. 8 titanium dioxide of the present invention;

Fig. 10 is a SEM image of No. 9 titanium dioxide of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Example 1

S1, weigh 8.00g (0.05mol) solid titanyl sulfate and 5.30g (0.05mol) solid sodium carbonate in a ceramic mortar;

S2. The added surfactant is cetyl trimethyl ammonium bromide (CTAB), which is ground in a ceramic mortar for 3 minutes, and the ratio of the amount of the surfactant to the total amount of the reactants is 2%;

S3, 3mL of water is added to the solid mixture, and the grinding is continued for 60min;

S4. After grinding, transfer the mixture to a centrifuge tube, centrifuge it on a centrifuge, pour off the supernatant, add water, stir with a glass rod for 2min-5min, and centrifuge again. Repeat the centrifugation for 3 times to complete 3 secondary washing process;

S5. The washed solid is placed in an oven at 110° C. for drying for 1 h;

S6. Put the dried powder into the muffle furnace for calcination for 1.5h, and the calcination temperature range is 500℃;

S7. Finally, the calcined sample is put into a sample bag for use.

The obtained titania powder was detected by XRD, and as shown in FIG. 1( a ), it was anatase-type titania with a particle size of 11.19 nm. The observation results of the SEM indicated that, as shown in FIG. 2 , the titanium dioxide at this time exhibited an irregular morphology.

Example 2

S1, weigh 8.00g (0.05mol) solid titanyl sulfate and 5.30g (0.05mol) solid sodium carbonate in a ceramic mortar;

S2, the added surfactant is sodium dodecyl benzene sulfonate (SDBS), which is ground in a ceramic mortar for 3 minutes, and the ratio of the amount of the surfactant to the total amount of the reactants is 4%;

S3, 3mL of water is added to the solid mixture, and the grinding is continued for 60min;

S4. After grinding, transfer the mixture to a centrifuge tube, centrifuge it on a centrifuge, pour off the supernatant, add water, stir with a glass rod for 2min-5min, centrifuge again, and repeat the centrifugation 4 times to complete 4 secondary washing process;

S5, placing the washed solid in an oven at 100°C for drying for 2h;

S6. Put the dried powder into a muffle furnace for calcination for 1 hour, and the calcination temperature range is 700°C;

S7. Finally, the calcined sample is put into a sample bag for use.

The obtained product was examined by XRD, as shown in Fig. 1(b), and the result showed that the particle size of titanium dioxide was 29.84 nm, and the crystal type was anatase type. The corresponding SEM is shown in Fig. 3, indicating that the titanium dioxide is a mixed structure of rod-like (a small amount) and random (a large amount) at this time.

Example 3

S1, weigh 8.00g (0.05mol) solid titanyl sulfate and 5.30g (0.05mol) solid sodium carbonate in a ceramic mortar;

S2, the added surfactant is polyethylene glycol (PEG-10000) with a molecular weight of 10,000 as a non-ionic surfactant, and the proportion of the amount of the surfactant to the total amount of the reactants is 6%;

S3, 3mL of water is added to the solid mixture, and the grinding is continued for 60min;

S4. After grinding, transfer the mixture to a centrifuge tube, centrifuge it on a centrifuge, pour off the supernatant, add water, stir with a glass rod for 2min-5min, and centrifuge again. Repeat the centrifugation for 3 times to complete 3 secondary washing process;

S5. The washed solid is placed in an oven at 100° C. for drying for 1 h;

S6. Put the dried powder into a muffle furnace for calcination for 1 hour, and the calcination temperature range is 900°C;

S7. Finally, the calcined sample is put into a sample bag for use.

The obtained product was detected by XRD, as shown in Fig. 1(c), the result showed that the particle size of titanium dioxide was 42.59 nm, and the crystal type was rutile. The corresponding SEM is shown in Fig. 4, indicating that the titanium dioxide is a mixed structure of cubic (a large amount) and rod-like (a small amount) at this time.

Example 4

S1, weigh 8.00g (0.05mol) solid titanyl sulfate and 5.30g (0.05mol) solid sodium carbonate in a ceramic mortar;

S2, the added surfactant is anionic surfactant sodium dodecylbenzene sulfonate (SDBS), and the proportion of the amount of the surfactant to the total amount of the reactant is 2%;

S3, 5mL of water is added to the solid mixture, and the grinding is continued for 60min;

S4. After grinding, transfer the mixture to a centrifuge tube, centrifuge it on a centrifuge, pour off the supernatant, add water, stir with a glass rod for 2min-5min, centrifuge again, and repeat the centrifugation 4 times to complete 4 secondary washing process;

S5. The washed solid is placed in an oven at 120°C for drying for 0.5h;

S6, put the dried powder into the muffle furnace for calcination for 1.5h, and the calcination temperature range is 900℃;

S7. Finally, the calcined sample is put into a sample bag for use.

The obtained product was detected by XRD, as shown in Figure 1(d), and the result showed that the particle size of titanium dioxide was 38.53 nm, and the crystal type was rutile. The corresponding SEM is shown in Fig. 5, indicating that the titanium dioxide has a cubic structure at this time.

Example 5

S1, weigh 8.00g (0.05mol) solid titanyl sulfate and 5.30g (0.05mol) solid sodium carbonate in a ceramic mortar;

S2, the added surfactant is anionic surfactant sodium dodecylbenzene sulfonate (SDBS), and the proportion of the amount of the surfactant to the total amount of the reactants is 4%;

S3, 5mL of water is added to the solid mixture, and the grinding is continued for 60min;

S4. After grinding, transfer the mixture to a centrifuge tube, centrifuge it on a centrifuge, pour off the supernatant, add water, stir with a glass rod for 2min-5min, centrifuge again, and repeat the centrifugation 4 times to complete 4 secondary washing process;

S5, placing the washed solid in an oven at 100°C for drying for 2h;

S6. Put the dried powder into a muffle furnace for calcination for 2 hours, and the calcination temperature range is 500 °C;

S7. Finally, the calcined sample is put into a sample bag for use.

The obtained product was detected by XRD, as shown in Fig. 1(e), and the result showed that the particle size of titanium dioxide was 17.90 nm, and the crystal type was anatase type. The corresponding SEM is shown in Fig. 6, indicating that the titanium dioxide has a random structure at this time.

Example 6

S1, weigh 8.00g (0.05mol) solid titanyl sulfate and 5.30g (0.05mol) solid sodium carbonate in a ceramic mortar;

S2, the added surfactant is the cationic surfactant cetyl trimethyl ammonium bromide (CTAB), and the proportion of the amount of the surfactant to the total amount of the reactants is 6%;

S3, 5mL of water is added to the solid mixture, and the grinding is continued for 60min;

S4. After grinding, transfer the mixture to a centrifuge tube and centrifuge it on a centrifuge. After finishing, pour off the supernatant, add water, stir with a glass rod for 2min-5min, and centrifuge again. Repeat the centrifugation five times to complete five secondary washing process;

S5. The washed solid is placed in an oven at 110°C for drying for 2h;

S6. Put the dried powder into a muffle furnace for calcination for 1 hour, and the calcination temperature range is 700°C;

S7. Finally, the calcined sample is put into a sample bag for use.

The obtained product was tested by XRD, as shown in Figure 1(f), the results showed that the particle size of titanium dioxide was 25.43nm, and the crystal type was a mixed crystal phase of rutile and anatase, of which rutile accounted for 59.17%, The anatase phase accounts for 40.83%. The corresponding SEM is shown in Fig. 7, indicating that the titanium dioxide has a random structure at this time.

Example 7

S1, weigh 8.00g (0.05mol) solid titanyl sulfate and 5.30g (0.05mol) solid sodium carbonate in a ceramic mortar;

S2, the added surfactant is polyethylene glycol (PEG-10000) with a molecular weight of 10,000 as a non-ionic surfactant, and the ratio of the amount of the surfactant to the total amount of the reactants is 2%;

S3, 7mL of water is added to the solid mixture, and the grinding is continued for 60min;

S4. After grinding, transfer the mixture to a centrifuge tube and centrifuge it on a centrifuge. After finishing, pour off the supernatant, add water, stir with a glass rod for 2min-5min, and centrifuge again. Repeat the centrifugation five times to complete five secondary washing process;

S5. The washed solid is placed in an oven at 100°C for drying for 0.5h;

S6, put the dried powder into the muffle furnace for calcination for 1.5h, and the calcination temperature range is 700℃;

S7. Finally, the calcined sample is put into a sample bag for use.

The obtained product was detected by XRD, as shown in Figure 1(g), the results showed that the particle size of titanium dioxide was 20.37nm, and the crystal type was a mixed crystal phase of rutile type and anatase type, of which rutile phase accounted for 48.71%, The anatase phase accounted for 51.29%. The corresponding SEM is shown in Fig. 8, indicating that the titanium dioxide has a random structure at this time.

Example 8

S1, weigh 8.00g (0.05mol) solid titanyl sulfate and 5.30g (0.05mol) solid sodium carbonate in a ceramic mortar;

S2, the added surfactant is that the cationic surfactant is cetyl trimethyl ammonium bromide (CTAB), and the ratio of the amount of the surfactant to the total amount of the reactants is 4%;

S3, 7mL of water is added to the solid mixture, and the grinding is continued for 60min;

S4. After grinding, transfer the mixture to a centrifuge tube, centrifuge it on a centrifuge, pour off the supernatant, add water, stir with a glass rod for 2min-5min, centrifuge again, and repeat the centrifugation 6 times to complete 6 secondary washing process;

S5. The washed solid is placed in an oven at 110°C for drying for 2h;

S6. Put the dried powder into a muffle furnace for calcination for 2 hours, and the calcination temperature range is 900°C;

S7. Finally, the calcined sample is put into a sample bag for use.

The obtained product was detected by XRD, as shown in Figure 1(h), the result showed that the particle size of titanium dioxide was 47.61 nm, and the crystal type was rutile. The corresponding SEM is shown in Fig. 9, indicating that the titanium dioxide has a mixed structure of rod-like (small amount) and cubic (large amount) at this time.

Example 9

S1, weigh 8.00g (0.05mol) solid titanyl sulfate and 5.30g (0.05mol) solid sodium carbonate in a ceramic mortar;

S2, the added surfactant is an anionic surfactant which is sodium dodecylbenzenesulfonate (SDBS), and the proportion of the amount of the surfactant to the total amount of the reactant is 6%;

S3, 7mL of water is added to the solid mixture, and the grinding is continued for 60min;

S4. After grinding, transfer the mixture to a centrifuge tube and centrifuge it on a centrifuge. After finishing, pour off the supernatant, add water, stir with a glass rod for 2min-5min, and centrifuge again. Repeat the centrifugation for 7 times to complete 7 secondary washing process;

S5. The washed solid is placed in an oven at 120° C. for drying for 1 h;

S6. Put the dried powder into a muffle furnace for calcination for 2 hours, and the calcination temperature range is 500 °C;

S7. Finally, the calcined sample is put into a sample bag for use.

The obtained product was detected by XRD, as shown in Figure 1(i), the result showed that the particle size of titanium dioxide was 16.11 nm, and the crystal type was anatase type. The corresponding SEM is shown in Fig. 10, indicating that the titanium dioxide has a random structure at this time.

The titanium dioxide powder obtained in the above-mentioned embodiment is detected by XRD, as shown in Figure 1, the results show that changing the four factors in the orthogonal table (water consumption, surfactant consumption, surfactant type and calcination temperature), titanium dioxide crystal form changed. Titanium dioxide samples range from No. 1 to No. 9. (a)-(i) in Figure 1 respectively represent the XRD patterns of No. 1-9 titanium dioxide samples, and their particle sizes are constantly changing (Figure 1, Table 2). The minimum particle size is 11.19nm, the maximum particle size is 47.61nm, and No. 1, No. 2, No. 5 and No. 9 all obtained pure anatase type titanium dioxide, No. 3, No. 4 and No. 8 all obtained pure rutile type titanium dioxide, No. 6 and No. 7 The mixed crystal phases of anatase and rutile were obtained. The orthogonal data is analyzed by the range method. As shown in Table 2, four factors (water amount, surfactant amount, surfactant type and calcination temperature) all have an influence on the particle size of titanium dioxide, and the degree of influence varies from large to large. The smallest order is the calcination temperature, the amount of surfactant, the type of surfactant, and the amount of water, and the optimal solution is determined as the calcination temperature of 500 ° C, the amount of surfactant is 2%, and the type of surfactant is a polymer with a molecular weight of 10,000. The dosage of ethylene glycol (PEG-10000) and water is 5 mL, and the particle size of titanium dioxide prepared according to this parameter is theoretically lower than 11.19 nm.

The obtained titanium dioxide powder was detected by SEM, as shown in Figure 2-10, which represented samples No. 1-9 in the orthogonal table in turn. The results showed that the four factors in the orthogonal table (water consumption, surfactant consumption, surfactant type and calcination temperature), the morphology of TiO2 changes. No. 1, No. 5, No. 6, No. 7, No. 9 titanium dioxide samples are all irregular structures, No. 2 titanium dioxide sample is a small amount of rod-shaped and a large number of irregular mixed structures, No. 3 and No. 8 titanium dioxide samples are a small amount of rod-shaped and Plenty of cube-like hybrid structures, while No. 4 is a cube-like structure. Therefore, by changing different experimental parameters, titanium dioxide powders with different morphologies (random, random, rod-like, cubic, and cubic) can be obtained.

Table 1. The parameters of the orthogonal experiment

Table 2. Analysis table of orthogonal experimental data calculated by range method

Kn represents the sum of the indicators of the nth level of the factor, kn represents the average value of Kn, and n is 1, 2, 3.

In the description of this specification, description with reference to the terms "one embodiment," "example," "specific example," etc. means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one aspect of the present invention. in one embodiment or example. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing has shown and described the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above-mentioned embodiments. The above-mentioned embodiments and descriptions only illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will also have Various changes and modifications fall within the scope of the claimed invention.

Claims (8)

1. A method for preparing titanium dioxide powders with different shapes by a solid-phase method, characterized in that the method comprises the following steps:

   S1: take by weighing titanyl sulfate solid and sodium carbonate solid in a ceramic mortar, and the mol ratio of titanyl sulfate solid and sodium carbonate solid is 1:1;

   S2: add different surfactants in a ceramic mortar and grind for 3min, wherein the cationic surfactant is cetyltrimethylammonium bromide, the anionic surfactant is sodium dodecylbenzenesulfonate, nonionic surfactant The surfactant is polyethylene glycol with a molecular weight of 10,000;

   S3: 3mL-7mL water is added in the solid mixture, continue to grind 60min;

   S4: after grinding, transfer the mixture to a centrifuge tube, centrifuge on a centrifuge, pour off the supernatant after finishing, add water, stir with a glass rod for 2min-5min, centrifuge again, repeat the centrifugation five times, complete five secondary washing process;

   S5: the solid after washing is placed in an oven at 110 ° C and dried for 1 h;

   S6: put the dried powder into a muffle furnace for calcination for 1.5h, and the calcination temperature range is 500°C-900°C;

   S7: The calcined sample is put into a sample bag for use.
2. The method for preparing titanium dioxide powders with different shapes by a solid-phase method according to claim 1, wherein the sodium carbonate in the S1 is anhydrous sodium carbonate or hydrated sodium carbonate.
3. The method for preparing titanium dioxide powders with different shapes by a solid-phase method according to claim 1, wherein the surfactant in the S2 is a cationic surfactant, an anionic surfactant or a nonionic surfactant.
4. The method for preparing titanium dioxide powders with different shapes by a solid-phase method according to claim 3, wherein the cationic surfactant cetyltrimethylammonium bromide, the anionic surfactant dodecane Sodium benzenesulfonate and polyethylene glycol with a molecular weight of 10,000 as a non-ionic surfactant, and the proportion of the surfactant in the total amount of the reactants is 2%-6%.
5. The method for preparing titanium dioxide powder with different shapes by a solid-phase method according to claim 1, wherein the amount of water in the S3 is 3mL-7mL, and the grinding time is 30min-90min.
6. The method for preparing titanium dioxide powders with different shapes by a solid-phase method according to claim 1, wherein the number of times of water washing in the S4 is 3 to 7 times.
7. The method for preparing titanium dioxide powders with different morphologies by a solid-phase method according to claim 1, wherein the drying temperature in the S5 is 100°C-120°C, and the drying time is 0.5h-2h.
8. The method for preparing titania powders with different shapes by a solid-phase method according to claim 1, wherein the calcination temperature in the S6 is 500°C-900°C, and the calcination time is 1h-2h.

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