JP2918112B1 - Method for producing anatase-type titanium oxide - Google Patents

Abstract

An anatase-type titanium oxide powder having a high photocatalytic activity and a large specific surface area is produced at a low temperature of 250 ° C. or less and with a small number of steps. Produce an anatase-type titanium oxide slurry having high storage stability and dispersibility. It is assumed that the obtained slurry can be coated on a material having low heat resistance as a coating material having photocatalytic activity. SOLUTION: A titania sol solution, a titania gel body or a titania sol-gel mixture is subjected to a heat treatment and a pressure treatment in a closed container and then dried to obtain an anatase type titanium oxide powder. Also, a titania sol solution,
The titania gel or the titania sol-gel mixture is subjected to heat treatment and pressure treatment in a closed container, and then dispersed and stirred to obtain an anatase type titanium oxide slurry.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to the removal of harmful substances,
As one of the photocatalysts used as an environmental purification material such as deodorant decomposition of deodorant substances, antifouling, sterilization, etc., particularly a method for producing anatase type titanium oxide having a large photocatalytic activity,
The present invention relates to a method for producing an anatase-type titanium oxide powder having high photocatalytic activity and a large specific surface area, and a method for producing an anatase-type titanium oxide slurry containing the anatase-type titanium oxide powder and having excellent stability and dispersibility.

[0002]

2. Description of the Related Art Photocatalysts are harmful substances (aldehydes, etc.) removed by radical substances (hydroxyl radicals, superoxide anions) generated when ultraviolet rays are irradiated on the surface, and malodorous substances (regulated by the Odor Control Law). Substances that have functions such as deodorization, decomposition, antifouling, and sterilization. In recent years, the use of the above functions has been attempted by coating the surface with this photocatalyst, and many oxides can be used as a photocatalyst, but titanium oxide is used as one of the photocatalysts. In particular, anatase-type titanium oxide is excellent in both functionality and safety. That is, titanium oxide includes three types of crystals, anatase type, rutile type, and brookite type, and amorphous type (amorphous type). Titanium oxide having the largest photocatalytic activity is anatase type.

[0003] As a method for obtaining anatase type titanium oxide powder, there are a gas phase method and a liquid phase method. Hereinafter, conventional techniques will be described for each method. As a representative anatase-type titanium oxide produced by a gas phase method, DegussaP-
25 (manufactured by Nippon Aerosil Co., Ltd.), which produces titanium oxide powder having a specific surface area of 40 m ² / g (BET method) by hydrolyzing titanium chloride at a high temperature of 1000 ° C. in an oxygen atmosphere. is there. In addition, there is a report that an anatase type titanium oxide can be obtained by preparing a furnace in a temperature range of 600 ° C. to 800 ° C. by a CVD (Chemical Vapor Deposition) method (Chemical Engineering Transactions Vol. 16). No. 3, pages 584 to 587, issued May 1990).

A method for obtaining anatase type titanium oxide by a liquid phase method includes a sol-gel method and a HyCOM method (Hydro method).
thermal Crystallisation in
Organic Media) and the sulfuric acid method have been proposed. Titanium oxide by the sol-gel method is obtained from alkoxide by the same operation as obtaining silica, and a step of obtaining titanium hydroxide by hydrolysis, and sintering to obtain titanium oxide by polycondensing titanium hydroxide by heating. Two steps are required. In addition, all the steps are performed under normal pressure. (For the sol-gel method, see, for example, "Sol-gel method science, pp. 8-15, issued in July 1988, Agne Shofusha") When anatase-type titanium oxide is obtained by the sol-gel method ,
As described above, the sintering step is indispensable, and the heating temperature for sintering needs to be in the range of 300 ° C to 700 ° C. The reason why the heat treatment at a specific range of temperature is necessary is that when the heat treatment is performed at a temperature lower than 300 ° C., the obtained titanium oxide remains amorphous, while when the heat treatment is performed at a temperature exceeding 700 ° C., the anatase type is obtained. This is because the titanium oxide of the above crystal transitions to a rutile type having a low photocatalytic function.

[0005] In the HyCOM method, titanium alkoxide is dissolved by applying pressure (10 kg / cm ² G) to water in a gas or steam-like water generated from another water storage tank as water necessary for hydrolysis of the alkoxide. By supplying it to a solvent, titanium oxide is obtained. In this case, the solvent in which the alkoxide is dissolved and the water are separately arranged in the apparatus. That is, there is no moisture in the raw material. HyCO
When titanium oxide is obtained by the M method, anatase-type titanium oxide which is anatase-type even after calcination at 900 ° C. and has excellent heat resistance such as maintaining the specific surface area at 40 m ² / g has been obtained (J. Mater.Sci.Lett., 1
5,197 (1996)).

[0006] The sulfuric acid method is disclosed in Japanese Unexamined Patent Publication No. 7-171408.
As described in the publication, sodium hydroxide is added to an acidic titanium sol obtained by heating and hydrolyzing titanium sulfate to adjust the pH to 7, followed by filtration and washing to obtain crystals. Then, water was added to the obtained titanium oxide wet cake to prepare a titanium oxide slurry. Further, sodium hydroxide was added to adjust the pH to 7, and then the autoclave was used.
Hydrothermal treatment is performed at 0 ° C. for 3 hours. Thereafter, nitric acid was added to the slurry after the hydrothermal treatment to adjust the pH to 7, followed by filtration, washing with water, and drying (110 ° C., 3 hours) to obtain titanium oxide.

Next, a conventional technique for producing a titanium oxide-containing liquid and a slurry will be described. JP-A-8-
As described in JP-A-99041, polyethylene glycol or ethylene oxide is added to a titania sol prepared from an alkoxide of titanium and an alcoholamine, and coated on a substrate, and then gradually heated from room temperature to a temperature of 600 to 700 ° C. By heating, an anatase type titanium oxide thin film is obtained. The above publication describes that the firing temperature is preferably from 600 ° C. to 700 ° C., and a sintering step is essential to obtain anatase type titanium oxide. JP-A-8-277147
Japanese Patent Application Laid-Open Publication No. H11-176,019 proposes a coating material prepared by a sol-gel method, but has a firing step at 350 ° C. JP-A-8-
Japanese Patent Application Laid-Open No. 21557 also proposes that a titanium oxide sol obtained by hydrolyzing titanyl sulfate diluted with water is used as a coating material, but this is also subjected to a baking treatment in the air at 300 ° C. .

JP-A-8-257360 discloses an anatase type titanium oxide powder (P-25,
Nippon Aerosil Co., Ltd.) is dispersed in water together with fine cellulose, and then polyaluminum chloride is added as a coagulant to prepare a slurry material. In the technique of dispersing powdery anatase-type titanium oxide in water, for example, using ilmenite as a raw material, dispersing titanium oxide in a mixture of nitric acid and metatitanic acid obtained by a sulfuric acid method, and dispersing as a coating material Those that improve storage stability have been reported (Industrial Materials Vol. 45,
No. 10, p48 (1997)).

[0009]

In the case of obtaining anatase type titanium oxide powder by a gas phase method, in any of the above methods, when preparing anatase type titanium oxide, the reaction atmosphere is heated to a high temperature (in the gas phase method, usually, 800 ° C. or higher) and the use of highly reactive titanium chloride as a raw material requires a special device. The method for producing anatase-type titanium oxide by the gas phase method described above is a dry method, which is a completely different technique from the method for producing anatase-type titanium oxide of the present invention by the liquid phase method. Further, even when the anatase type titanium oxide powder is obtained by the sol-gel method, the sintering step is essential as described above,
A heat treatment at 300 ° C. or higher is required.

According to the HyCOM method, anatase-type titanium oxide having excellent heat resistance can be obtained as described above, but there is a drawback that a special apparatus is required for the preparation. In the case of the HyCOM method, the solvent in which the alkoxide is dissolved and water are separately arranged in the apparatus, and there is no moisture in the raw material.
In the present invention, water is added in advance to titanium alkoxide as a raw material to carry out a hydrolysis reaction to titanium hydroxide, and both are completely different techniques in operation method and the like. Further, when the anatase type titanium oxide is obtained as a powder by the sulfuric acid method, the number of steps is large and the operation and the like are very complicated.

A coating material prepared by hydrolysis of an anatase-type titanium oxide-containing slurry, that is, a slurry, requires a heat treatment step at 300 ° C. or more in order to finally obtain anatase-type titanium oxide. . However, this cannot coat the base material having low heat resistance, and the usable base material is limited. In addition, when preparing the coating material, even if powdered anatase-type titanium oxide is dispersed in a solvent, the titanium oxide particles aggregate, and the activity of the fine-particle photocatalyst cannot be maintained. As a coating material, anatase-type titanium oxide is not uniformly dispersed in a solution, and there is a problem in storage stability such that the titanium oxide particles settle under the solution over time. The technique of dispersing titanium oxide in a mixture of nitric acid and metatitanic acid obtained by a sulfuric acid method using ilmenite as a raw material as described above also has a problem such as aggregation of particles as described above.

The present invention has been made in view of the above points, and an object of the present invention is to heat treat titania sol, titania gel, or a titania sol-gel mixture in a closed vessel to hybridize the effect of pressure. Accordingly, it is an object of the present invention to provide a method capable of easily producing an anatase type titanium oxide powder having a high photocatalytic activity and a large specific surface area at a low temperature of 250 ° C. or lower and with a small number of steps. Further, an object of the present invention is to heat-treat in an airtight container and simultaneously pressurize the obtained anatase type titanium oxide, titania sol, titania gel or ultrasonic dispersion in a solvent used for preparing a titania sol-gel mixture. By stirring, etc., very stable at room temperature,
An object of the present invention is to provide a method capable of producing an anatase type titanium oxide slurry which does not cause precipitation of titanium oxide particles and can be coated on a material surface having low heat resistance.

[0013]

In order to achieve the above object, a method for producing anatase type titanium oxide of the present invention comprises the steps of:
The alcohol represented by the structural formula of C _n H _{2n + 1} OH is used as a solvent
The titania sol solution, the titania gel body or the titania sol-gel mixture is heated and pressurized in a closed container at the same time, and then dried to obtain an anatase type titanium oxide powder. The manufacturing method of an anatase-type titanium oxide of the present invention, C
alcohols represented by the structural formula of _n H _{2n + 1} OH
The titania sol solution, the titania gel body or the titania sol-gel mixture was heated and treated at the same time as the heat treatment in a closed container, and then dispersed or stirred by ultrasonic waves to form an anatase-type titanium oxide slurry. It is characterized by obtaining. As described above, as the stirring operation, it is of course possible to perform mechanical stirring and the like in addition to the dispersion by the ultrasonic waves.

In these cases, as a starting material for producing a titania sol or a titania gel, for example, metal alkoxides as metal organic compounds, titanium oxalate, and titanium nitrate and titanium tetrachloride as metal inorganic compounds can be used. Examples of the metal alkoxide include titanium tetramethoxide, titanium tetraethoxide, titanium isopropoxide, and titanium tetrabutoxide.

In the above method of the present invention, it is preferable to heat-treat the titania sol solution, the titania gel or the titania sol-gel mixture at a temperature in the range of 80 to 250 ° C. in a closed vessel. As for the temperature for heating the inside of the closed container, it is necessary to vaporize the solvent (solvent) in which the raw materials are dissolved, and thus it is necessary to perform the treatment at 80 to 250 ° C. as described above. When the treatment is performed at a heating temperature of less than 80 ° C., it takes a long time to evaporate all the solvent, so that sufficient pressurization cannot be performed. Is not obtained very much and is not practical. On the other hand, in processing at a temperature exceeding 250 ° C.,
Special structures and equipment such as hermetic containers and sealing materials to be used are required.

In the method of the present invention, the titania sol solution, the titania gel or the titania sol-gel mixture is subjected to pressure treatment in a closed vessel at a pressure of 50 to 350 atmA, preferably 100 to 320 atmA. Is preferred. As described above, the processing pressure in the closed container has a lower limit of 50 atmA, preferably 100 atmA, and an upper limit of 350 atmA, preferably 320 atmA. If the pressure in the closed container is less than the above lower limit, the dispersibility of the produced anatase type titanium oxide slurry becomes poor, while if the pressure in the closed container exceeds the above upper limit, for pressurization Requires extra equipment and facilities.
Further, in the method of the present invention, by heating the inside of the closed container, the solvent (solvent) contained in the titania sol solution, the titania gel body or the titania sol-gel mixture is evaporated, and the inside of the closed container is evaporated by the evaporated solvent gas. It is preferable to apply pressure. In this case, the pressure in the closed container can be controlled by the volume of the closed container and the amount of the solvent, whereby the processing pressure can be set within the above-described range. Further, by introducing a pressurized inert gas into the closed container, the pressure in the closed container can be controlled.

[0017] As described above, titania sol solution, a titania gel, or titania sol-gel mixture, C _n H
An alcohol represented by the structural formula _{2n + 1} OH Ru contained as a solvent. As a solvent for dissolving the raw material, any solvent may be used as long as it is a solvent for dissolving titania sol or titania gel. In particular, alcohols represented by the structural formula of C _n H _{2n + 1} OH are used. For example, it is desirable to use methanol, ethanol, 1-propanol, isopropyl alcohol, 1-butanol, 2-butanol, isobutyl alcohol, ter-butyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol and the like. .

In these methods of the present invention, it is preferable to add at least one of an acidic substance, an alkaline substance, an organic polymer and an inorganic substance to the titania sol solution, titania gel or titania sol-gel mixture. Raw materials such as titania sol include, if necessary, acidic substances such as hydrochloric acid, nitric acid, and acetic acid, alkaline substances such as ammonia and amine compounds, inorganic substances such as silica, polymethacrylic acid resins, fluororesins, and aromatic organic compounds. Molecules and the like can be added.

[0019]

Next, an embodiment of the present invention will be described. In the present embodiment, as an example, a case is described in which titania sol is used as a raw material and alcohols represented by the structural formula of C _n H _{2n + 1} OH are used as a solvent for dissolving the titania sol. -It is of course possible to use the gel mixture as a raw material, and it is of course possible to use other solvents as long as the solvent dissolves titania sol or titania gel. As a starting material for producing a titania sol, for example, a metal alkoxide, which is a metal organic compound, titanium oxalate, and titanium nitrate, titanium tetrachloride as a metal inorganic compound can be used. As metal alkoxides,
There are titanium tetramethoxide, titanium tetraethoxide, titanium isopropoxide, and titanium tetrabutoxide. Further, as a solvent for dissolving the starting material or titania sol, for example, methanol, ethanol, 1-propanol, isopropyl alcohol, 1-butanol,
2-butanol, isobutyl alcohol, ter-butyl alcohol, 1-pentanol, 2-pentanol,
3-pentanol and the like.

A titania sol solution is prepared from the above-mentioned raw materials (for example, metal alkoxide and the like) and a solvent (solvent),
Put the obtained titania sol solution in a closed container,
Heat treatment at a temperature in the range of 250 ° C. When preparing the titania sol, if necessary, an acidic substance such as hydrochloric acid, nitric acid, and acetic acid, an alkaline substance such as ammonia and an amine compound, an inorganic substance such as silica, a polymethacrylic acid resin, a fluororesin, and an aromatic organic compound may be used. Add molecules and the like.
The solvent (solvent) used for preparing the titania sol solution evaporates by heating and holding in the closed container, and the inside of the closed container is pressurized by the evaporated solvent gas. The processing pressure in the closed container has a lower limit of 50 atmA, preferably 100 atmA.
atmA and the upper limit is 350 atmA, preferably 320
Adjust to atmA. In this case, the pressure can be controlled by the volume of the closed container and the amount of the solvent. During the heat treatment, an inert gas such as nitrogen gas may be introduced into the closed container to control the pressure in the closed container within the above range.

A liquid containing anatase type titanium oxide is obtained by the above two steps of the titania sol preparation step and the heat treatment step. At this time, the fine particles of anatase-type titanium oxide are settled in the lower part of the solvent (solvent), and by evaporating and drying the solvent at a temperature of about 100 ° C., an anatase-type titanium oxide powder exhibiting high photocatalytic activity is obtained. Can be In this case, the solvent after the above treatment can be recovered with almost no loss. The specific surface area of the obtained anatase type titanium oxide powder is 50 to 100 m ² / g, and has a high specific surface area. In addition, as a method of measuring the specific surface area, for example, a BET method or the like can be mentioned. In addition, since the fine particles of anatase-type titanium oxide are settled below the solvent (solvent), the precipitated titanium oxide particles are dispersed in the solution by ultrasonic treatment, and are extremely stable at room temperature. In addition, an anatase-type titanium oxide slurry without precipitation of titanium oxide particles can be obtained. As described above, the titanium oxide particles can be dispersed in the solvent used for preparing the titania sol. As the stirring operation, mechanical stirring and the like can be performed in addition to the dispersion by ultrasonic waves. The obtained anatase-type titanium oxide slurry is used as a coating material having excellent photocatalytic activity.
Coating can be performed at a temperature of about 00 ° C.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention and comparative examples will be described below. Example 1 Titanium isopropoxide (14.96 g) was dissolved in isopropanol (50 ml) to prepare a titanium isopropoxide solution, which was previously mixed with 2N hydrochloric acid (2.5 ml), water (3 ml), and isopropanol (94.5 ml) to give titanium isopropoxide. The solution was added dropwise at 10 ml per minute for 5 minutes, ie, 50 ml. The molar ratio of titanium isopropoxide, water, and hydrochloric acid in the obtained titania sol solution was 1: 3: 0.05. 50 g of the obtained transparent titania sol was placed in a 100 ml container, and kept at 240 ° C. for 6 hours in a sealed state.
At this time, the pressure in the sealed container rose to 320 atmA. After the white powder obtained after the treatment was dried at 110 ° C., the crystal structure was analyzed by X-ray diffraction (XRD). As shown in FIG. 2, the obtained crystal was one of anatase-type titanium oxides. A diffraction peak similar to that of P-25 (manufactured by Nippon Aerosil Co., Ltd.) (the XRD analysis result is shown in FIG. 1) was obtained, and anatase type titanium oxide was generated. The specific surface area of the generated anatase type titanium oxide was 67 m ² / g (BET method). The resulting powder is 9
Titanium oxide was contained in a yield of 8% or more, and the solvent loss after the heat treatment was 0.3%.

Comparative Example 1 When the titania sol prepared in Example 1 was kept at normal pressure and normal temperature without heat treatment in a closed container, the viscosity of the solution increased with the lapse of time. Formed. In addition, even if it was left thereafter, it remained a transparent gel, and no white powder was formed. Example 1
Immediately after preparation, the titania sol prepared in
C. for 5 hours and dried to obtain a white powder. This white powder was analyzed by X-ray diffraction (XRD).
As can be seen from the figure, it had an amorphous structure. Also,
The titania sol prepared in Example 1 was mixed with 400 g under normal pressure.
By treatment at ℃, anatase type titanium oxide was obtained (the XRD analysis result is shown in FIG. 4), but the powder was slightly gray due to residual organic substances.

Example 2 50 g of the transparent titania sol obtained in Example 1 was sealed in a 100 ml container and treated at 150 ° C. for 6 hours. As a result, a white powder was obtained. When this powder was analyzed by X-ray diffraction (XRD), as shown in FIG. 5, anatase type titanium oxide was formed.

Example 3 A liquid containing fine particles of anatase-type titanium oxide produced by heat treatment in a sealed state in Example 1 was treated for 10 minutes by an ultrasonic cleaner (high-frequency output: 65 W), and the sedimented oxidation was observed. Titanium particles were dispersed in the solution. The pH of the obtained slurry was 4.9, and the dispersion of the anatase-type titanium oxide did not precipitate even after standing for 20 days or more, and the anatase-type titanium oxide was dispersed extremely stably. This dispersion (slurry) was coated on the inner surface of a 1-liter glass separable flask and dried at 110 ° C. for 30 minutes. The amount of titanium oxide coated on the inner surface of the separable flask was 0.25 g. Low pressure mercury lamp (10W) in separable flask after titanium oxide coating
To evaluate the decomposition characteristics of 500 ppm of acetaldehyde. FIG. 6 shows the result. When the mercury lamp was not irradiated, the acetaldehyde concentration maintained the acetaldehyde concentration at the time of injection only by decreasing the amount of acetaldehyde adsorbed on the titanium oxide on the inner surface when injected into the flask (from -30 minutes to 0 minutes in FIG. 6). By)). By irradiation with a mercury lamp, the concentration of acetaldehyde in the flask decreased, and the entire amount disappeared in about 40 minutes. Furthermore, when the carbon dioxide (decomposition product of acetaldehyde) in the flask was analyzed, the carbon dioxide concentration in the flask increased simultaneously with the irradiation of the mercury lamp. From these facts, it can be seen that acetaldehyde was decomposed and removed by the anatase type titanium oxide having photocatalytic activity.

The X-ray measurement conditions and gas concentration measurement conditions in the above-described Examples and Comparative Examples are as shown below. (1) X-ray measurement conditions X-ray apparatus; PW3050 type manufactured by Nippon Philippe; X-ray source; Cu Kα ray output; tube voltage 40 kV, tube current 30 mA scanning; θ / 2θ scan scanning range (diffraction angle 2θ); 75 ° Scan speed; 0.05 ° (2θ / sec) Detector; Proportional counter (2) Measurement conditions of gas concentration Acetaldehyde; GC-FID (flame flame ionization detector) type (Shimadzu GC-14B) Column; DB- WAX (0.25 μm diameter, 30 length
m) Carrier gas flow rate: 41 ml / min (He) Split ratio; 1/40 (using make-up gas He) Column temperature; 100 ° C Injection temperature; 230 ° C Detector temperature; 250 ° C CO ₂ ; GC-FID (hydrogen flame) Ionization detector) type (Shimadzu GC-14A) Pretreatment performed at 400 ° C with a metanizer (MTN-1) Column; Polapack Q Carrier gas flow rate: 50 ml / min (hydrogen) Column temperature; 50 ° C Injection temperature; 100 ° C Detection Vessel temperature; 100 ℃

[0027]

As described above, the present invention has the following effects. (1) Since the titania sol, the titania gel, or the titania sol-gel mixture is subjected to heat treatment and pressure treatment in a closed container at a low temperature of 250 ° C. or less, anatase type titanium oxide powder exhibiting high photocatalytic activity. And a slurry containing the same. (2) Anatase-type titanium oxide can be produced in two steps of a raw material preparation step and a heat treatment step, which is a simple method with a small number of steps. (3) In the case of obtaining powdered titanium oxide, the solvent (solvent) may be evaporated and dried at a temperature of about 100 ° C. after the heat treatment, and the specific surface area of the obtained anatase type titanium oxide powder is 50 m ^2. / G to 100 m ² / g, and has a high specific surface area. (4) The solvent (solvent) in which the titanium oxide raw material is dissolved can be recovered without loss after the heat treatment, and can be used as a solvent for dispersing the generated anatase-type titanium oxide particles into a slurry. . (5) The anatase-type titanium oxide after heat treatment is present as fine particles under the solvent, but must be subjected to ultrasonic dispersion treatment (mechanical stirring is also possible) in the solvent (solvent) used for preparing the raw material. Accordingly, an anatase-type titanium oxide slurry that is extremely stable at room temperature and does not cause precipitation of titanium oxide particles can be produced. (6) The obtained anatase type titanium oxide slurry is
As a coating material with extremely high storage stability and dispersibility and excellent photocatalytic activity, it can be coated at a temperature of about 100 ° C., and can be coated on a material surface having low heat resistance.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention in which titanium oxide (P-2) is used.
It is a diagram which shows the analysis result of the crystal structure by X-ray diffraction (XRD) of 5).

FIG. 2 is a diagram showing an analysis result of a crystal structure of titanium oxide by X-ray diffraction (XRD) in Example 1 of the present invention.

FIG. 3 shows an X-ray diffraction (XR) of titanium oxide in Comparative Example 1.
It is a diagram which shows the analysis result of the crystal structure by D).

FIG. 4 shows an X-ray diffraction (XR) of titanium oxide in Comparative Example 1.
It is a diagram which shows the analysis result of the crystal structure by D).

FIG. 5 is a diagram showing an analysis result of a crystal structure of titanium oxide by X-ray diffraction (XRD) in Example 2 of the present invention.

FIG. 6 is a graph showing the results of testing the acetaldehyde decomposition characteristics of the obtained coating material in Example 3 of the present invention.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) C01G 1/00-23/08 A61L 9/00-9/04 A61L 9/14-9/22 B01J 21 / 00-38/74 CA (STN) REGISTRY (STN)

Claims (7)

(57) [Claims] _{1. An} alcohol represented by the structural formula of C _n H _{2n + 1} OH.
A titania sol solution containing titanic acid as a solvent, a titania gel body or a titania sol-gel mixture is subjected to a heat treatment and a pressure treatment simultaneously in a closed vessel, and then dried to obtain an anatase type titanium oxide powder. For producing anatase type titanium oxide. 2. An al compound represented by the structural formula of C _n H _{2n + 1} OH.
A titania sol solution containing titanic acid as a solvent, a titania gel body or a titania sol-gel mixture is subjected to a heat treatment and a pressure treatment in a closed container at the same time, and then dispersed or stirred by ultrasonic waves to produce anatase-type oxidation. A method for producing anatase type titanium oxide, comprising obtaining a titanium slurry. 3. A titania sol solution, a titania gel or a titania sol-gel mixture is placed in a closed container at 80 to 2 times.
The method for producing anatase-type titanium oxide according to claim 1 or 2, wherein the heat treatment is performed at a temperature in the range of 50 ° C. 4. A titania sol solution, a titania gel body or a titania sol-gel mixture is placed in a closed container at 50 to 3 times.
4. The method for producing anatase-type titanium oxide according to claim 1, wherein the pressure treatment is performed at a pressure in the range of 50 atmA. 5. The method according to claim 1, wherein the solvent contained in the titania sol solution, the titania gel or the titania sol-gel mixture is evaporated by heating the inside of the closed vessel, and the inside of the closed vessel is pressurized by the evaporated solvent gas. A method for producing anatase-type titanium oxide according to any one of the above. 6. The method for producing anatase-type titanium oxide according to claim 1, wherein the inside of the closed container is pressurized by introducing an inert gas into the closed container . 7. A titania sol solution, a titania gel, or titania sol-gel mixture, acidic substances, alkaline substances, anatase type according to any one of claims 1 to 6, adding at least one organic polymer and inorganic materials A method for producing titanium oxide.