JPH06199524A - Titanium oxide powder and production thereof - Google Patents

Abstract

PURPOSE:To obtain a titanium oxide powder excellent in deodorizing ability for malodor gas by depositing zinc and silicon in a specific ratio on a base body particle of titanium oxide. CONSTITUTION:The oxide of zinc and silicon are deposited on the base body particle of titanium oxide by Ti:Zn=9.9:0.1 to 5:5 in the mol ratio of Zn to Ti and Zn:Si=9:1 to 0.1:9.9 in the mol ratio of Si to Zn by adding a zinc compound (e.g. zinc chloride), a silicon compound (e.g. waterglass) and a neutralizer (e.g. water-soluble compound of alkali metal), neutralizing the zinc compound and the silicon compound to pH6-11 in a dispersing solution of the titanium oxide base particle, separating the obtained product and drying at 100-600 deg.C. The titanium oxide powder is excellent in deodorizing ability for malodor gas such as ammonia, methyl mercaptan, hydrogen sulfide, trimethylamine, methyl sulfide or acetoaldehyde and is capable of efficiently removing harmful substances by photocatalytic reaction.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a pigment, a catalyst, a catalyst carrier,
Titanium oxide powder useful as an adsorbent, etc., and more specifically, a deodorant that adsorbs unpleasant odorous gases such as ammonia, mercaptans, hydrogen sulfide, and aldehydes, and a harmful substance remover that decomposes harmful substances by photocatalytic reaction As a titanium oxide powder having a high specific surface area.

[0002]

2. Description of the Related Art As an unpleasant odorous gas which is likely to be generated in the human living environment, ammonia, methyl mercaptan, hydrogen sulfide, trimethylamine, methyl sulfide, acetaldehyde and the like can be mentioned. Attempts have been made to remove these malodorous gases and maintain the living environment comfortably. For example, a method of deodorizing activated carbon or impregnated carbon obtained by supporting acid or alkali on activated carbon to adsorb malodorous gas. Is taken. However, since this activated carbon and the like are black, the usable range is limited. For example, when blending activated carbon into hygiene products such as paper diapers and sanitary napkins that come into direct contact with the human body, it is necessary to treat the products so that they are not colored black in order to keep the product clean, and to keep indoor wallpaper and When the activated carbon is mixed with a decorative product or a cosmetic product, it is difficult to color the product into a desired color, and therefore it can be used only for a black product. Further, activated carbon has a particularly low deodorizing performance for ammonia, and further has a problem that if water is adsorbed first, the deodorizing performance for odorous gas is lowered. On the other hand, various adsorbents are commercially available, and silica gel, zeolite, activated alumina, activated clay, etc. are generally sold as white adsorbents that give a feeling of cleanliness and can color the product in a desired color. Has been done. However, these white adsorbents cannot be used in place of activated carbon because they have low deodorizing performance for the malodorous gas. Therefore,
Japanese Examined Patent Publication No. 3-33022 proposes tightly bound particles composed of zinc oxide, titanium dioxide and water as a white deodorant.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In order to obtain the white deodorant described in No. 22, a water-soluble titanium compound, a mixed aqueous solution of a water-soluble zinc compound and an alkaline aqueous solution are simultaneously combined so that the pH of the combined solution of both is in the range of 6 to 11. Let it neutralize, titanium dioxide,
It is necessary to obtain a close-bonded particle having a uniform composition of zinc oxide and water. In this method, it is necessary to finely control the concentration of the raw material such as a titanium compound and the rate of coalescence of the two, and the operation becomes complicated. In addition, p of the combined liquid
When H changes outside the above range, the white deodorant obtained is not excellent in characteristics.
No. 22. In addition, since the precipitate deposited by neutralization is in the form of gel, there are problems to be solved, such as difficulty in filtration and difficulty in pulverization because particles of the precipitate are solidified by drying.

[0004]

Means for Solving the Problems The present inventors have been making various studies for increasing the added value of titanium oxide as a functional material for some time, but in the process,
The research was advanced focusing on the application of titanium oxide as a white deodorant. As a result, titanium oxide
It was found that the deodorizing performance of basic gases such as trimethylamine was excellent, but the deodorizing performance of methyl mercaptan and hydrogen sulfide was low. As a result of further intensive studies thereafter, powder obtained by supporting titanium oxide substrate particles with zinc oxide obtained by neutralizing a zinc compound with a water-soluble alkali compound of an alkali metal or an alkaline earth metal. The body (1) is excellent in deodorizing performance of malodorous gas, and (2) does not require complicated operations, and filtration, drying of the product,
The present invention has been completed by finding that it is possible to easily perform pulverization and the like, and (3) it is easy to obtain a stable quality product, which is also suitable for practical use. Further, when a titanium oxide powder carrying a zinc oxide is further supported with a silicon oxide, the amount of zinc oxide dissolved is small, and
The present invention has been completed by finding out that the deodorizing performance of a malodorous gas is excellent. Furthermore, titanium oxide powder supporting zinc oxide or titanium oxide powder supporting further silicon oxide, when irradiated with light containing ultraviolet rays in the presence of oxygen, undergoes a photocatalytic reaction to produce a malodorous substance or an irritating substance. Finds that harmful substances such as substances that adversely affect the human body and living environment can be decomposed and removed, and in particular that the above-mentioned malodorous gas can be decomposed and removed to deodorize,
The present invention has been completed. That is, the present invention particularly relates to a white powder excellent in deodorizing performance of malodorous gas and a method for easily and easily producing the white powder.

The present invention relates to titanium oxide powder in which a specific amount of zinc oxide is supported on titanium oxide base particles, and further, titanium oxide powder in which specific amounts of zinc and silicon oxides are supported. The titanium oxide in the present invention includes so-called titanium oxide as well as hydrous titanium oxide. The zinc oxide means zinc oxide, zinc hydroxide and the like, and the silicon oxide means silicon oxide, silicic acid, silicate and the like. The term "supported" as used in the present invention means a state in which zinc oxide or silicon oxide is distributed or present in the form of islands on the surface of a single particle of titanium oxide base particles or an aggregate thereof. The state in which the entire surface of the particles is covered with a continuous coating layer, or the state in which they are incorporated in the gaps between the titanium oxide base particles, the titanium oxide base particles, zinc oxide, and silicon oxide are physically It may be in a state of being in physical or chemical contact. The amount of zinc oxide supported on the titanium oxide base particles can be arbitrarily changed according to the composition of the target malodorous gas, but generally, the molar ratio of Zn to Ti of the base is Ti: Zn = 9.
9: 0.1 to 5: 5, particularly 9.5: 0.5 to 7: 3 is desirable. When the supported amount is less than the above range, it is not desirable because the deodorizing performance of methyl mercaptan and hydrogen sulfide is deteriorated, and when the supported amount is more than the above range, the amount of free zinc oxide increases, and the deodorizing performance of ammonia and trimethylamine decreases. Is undesirable because

Further, the present invention is a titanium oxide powder in which oxides of zinc and silicon are supported on titanium oxide base particles, but the amount of the supported oxide of silicon is arbitrary depending on the composition of the target malodorous gas. Can be changed to Generally, zinc oxide is used as Zn with respect to Ti of the substrate in a molar ratio of T
i: Zn = 9.9: 0.1-5: 5, especially 9.5: 0.
5 to 7: 3, and the molar ratio of the silicon oxide to Zn of the zinc oxide is Si: Zn: Si = 9:
It is preferable to carry an amount of 1 to 0.1: 9.9, particularly 9: 1 to 4: 6. When the amount of silicon oxide supported is less than the above range, zinc oxide is easily dissolved in an aqueous solution, particularly an acidic aqueous solution, and when used in a deodorant such as a paper diaper, deodorizing performance is reduced, and eluted zinc ions are human body. It is not preferable because it may adversely affect Further, when the amount of silicon oxide carried is larger than the above range, the dissolution of zinc oxide is reduced, but the deodorizing performance against a specific malodorous gas is deteriorated, which is not preferable.

When the titanium oxide powder of the present invention is used as a deodorant, it is preferable that its specific surface area is 100 m ² / g or more in order to obtain a deodorant having a good deodorizing rate and deodorizing performance. When the specific surface area is less than 100 m ² / g, the deodorizing performance is substantially insufficient and it is difficult to obtain a suitable deodorizing agent.

In the method of the present invention, the titanium oxide powder in which the oxide of zinc is supported on the titanium oxide substrate particles is prepared by adding a zinc compound and an alkali to the dispersion liquid of the titanium oxide substrate particles. Neutralizing the zinc compound in a dispersion of particles, then fractionating the resulting product,
Obtained by drying. In the present invention, as the titanium oxide base particles, titanium oxide that can be obtained by various known methods can be used. As a method for obtaining titanium oxide, for example, titanyl sulfate, titanium chloride,
A method in which a titanium compound such as an organotitanium compound is heated and hydrolyzed in the presence of seeds for nucleation, if necessary, and an alkali is added to the titanium compound such as titanyl sulfate, titanium chloride, or an organotitanium compound to neutralize it. Examples thereof include a method, a method of vapor-phase oxidizing titanium chloride, an organic titanium compound, etc., and a method of firing the titanium oxide obtained by the above method at a temperature of about 600 ° C. or lower. The titanium oxide obtained by these methods. Can be used as titanium oxide base particles. In the present invention, the titanium oxide base particles are dispersed in a solvent such as water, and if necessary, classified to obtain a dispersion liquid. As the zinc compound added to this dispersion liquid, various compounds such as zinc chloride, zinc sulfate, and zinc nitrate can be used. Further, the alkali is preferably a water-soluble alkali compound of an alkali metal or an alkaline earth metal, and for example, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium bicarbonate, sodium silicate, barium hydroxide or the like is used. The use of ammonia or ammonium salt as the alkali is not preferable because it tends to form a complex ion with the zinc compound to dissolve the zinc oxide. As a method of neutralizing the zinc compound in the dispersion liquid of titanium oxide base particles,
For example, a method of simultaneously adding a zinc compound and an alkali to a dispersion liquid of titanium oxide base particles for neutralization, a method of adding a zinc compound to a dispersion liquid of titanium oxide base particles, and then adding an alkali for neutralization, Examples include a method in which an alkali is added to a dispersion liquid of titanium oxide base particles and then a zinc compound is added to neutralize the solution, but any method may be used. Zinc compounds are generally neutralized and precipitated in the pH range of about 6-11. The conditions such as the concentration of titanium oxide base particles in the dispersion, the amount of zinc compound or alkali added, the concentration and addition rate of each of these when used as an aqueous solution, and the temperature during the neutralization reaction are not particularly limited. Instead, it can be set appropriately. Also, prior to the neutralization reaction,
In order to improve the dispersion state of the titanium oxide base particles in the dispersion liquid, a dispersant such as orthophosphoric acid, pyrophosphoric acid, hexametaphosphoric acid or an alkali salt thereof, sodium orthosilicate, sodium metasilicate is added to the titanium oxide powder. It may be added to the dispersion within a range that does not adversely affect the deodorizing performance. The product thus obtained is separated, washed if necessary and then dried. Fractionation can be performed by a method such as ordinary filtration or decantation. The drying can be performed at a temperature of 100 to 600 ° C, but a temperature of 100 to 200 ° C is suitable. The dry powder can be crushed or crushed to obtain powder, or molded into granules depending on the use situation. Since the specific surface area of the titanium oxide powder obtained with loading of zinc oxide is increased to tend to decrease, the specific surface area to obtain a 100m ² / g greater than titanium oxide powder has a specific surface area of 100m It is desirable to use titanium oxide substrate particles of greater than ² / g.

Next, in the method of the present invention, the titanium oxide powder in which the oxides of zinc and silicon are supported on the titanium oxide substrate particles can be produced according to the above-mentioned method of supporting the oxide of zinc. . That is, by adding a zinc compound, a silicon compound, and a neutralizing agent to a dispersion liquid of titanium oxide base particles, the zinc compound and the silicon compound are neutralized in the dispersion liquid of titanium oxide base particles, and then, The product obtained is separated off and dried. Examples of the silicon compound include water glass, sodium orthosilicate,
Various substances such as sodium metasilicate and silicon chloride can be used. As the neutralizing agent, various acids such as hydrochloric acid, sulfuric acid and nitric acid can be used in addition to the above-mentioned alkali. The silicon compound can be neutralized according to the above-mentioned zinc compound neutralization method, but generally about 6 to
Neutralize and precipitate in the pH range of 11. The zinc compound and the silicon compound can be neutralized simultaneously or separately. When neutralized at the same time, zinc oxide and silicon oxide can be coprecipitated and supported, and when they are separately neutralized, for example, zinc oxide is supported and then silicon oxide is supported. You can also do it. When the titanium oxide powder of the present invention is used as a deodorant, first, a titanium compound is neutralized with an alkali or hydrolyzed to produce titanium oxide base particles in a liquid phase, and then the titanium oxide is continuously added. A method in which a zinc compound, a silicon compound and a neutralizing agent are simultaneously added to and supported on a liquid in which the base particles are dispersed is particularly preferable. Incidentally, the concentration of titanium oxide base particles in the dispersion,
There are no particular restrictions on the amount of silicon compound, zinc compound, or alkali added, and the conditions such as the concentration and addition rate of each of these when used as an aqueous solution, and the temperature during the neutralization reaction, which can be set appropriately. The product thus obtained is separated, washed if necessary, and dried in the same manner as in the above-mentioned method for supporting the oxide of zinc. Fractionation can be performed by a method such as ordinary filtration or decantation. The drying can be performed at a temperature of 100 to 600 ° C, but a temperature of 100 to 200 ° C is suitable. The dry powder can be crushed or crushed to obtain powder or molded into granules depending on the use situation.

In the present invention, a titanium oxide powder in which zinc oxide is supported on titanium oxide substrate particles or a titanium oxide powder in which zinc and silicon oxides are supported on titanium oxide substrate particles is directly used as a deodorant or harmful. It can be used as a substance remover, but can also be used as a mixture with substances commonly used in this field such as aluminum oxide and zeolite. Various malodorous gases can be efficiently deodorized by bringing the malodorous gas into contact with the deodorant containing the titanium oxide powder of the present invention. Further, the harmful substance removing agent containing the titanium oxide powder of the present invention is decomposed into various harmful substances efficiently by contacting the harmful substances with irradiation of light containing ultraviolet rays in the presence of oxygen. Can be removed. The ultraviolet ray used in the present invention is preferably near ultraviolet ray having a wavelength of 300 to 400 nm. The harmful substance removing agent containing the titanium oxide powder of the present invention can be applied to various harmful substances such as a foul-smelling substance, an irritating substance, and a substance having an adverse effect on the human body and the living environment. Examples thereof include decomposition and sterilization of air pollutants such as nitrogen oxides and sulfur oxides, water pollutants such as oils, and organic compounds such as polychlorinated biphenyls and dioxins.

[0011]

【Example】

Example 1 10 liters of a 2 mol / l titanyl sulfate solution was heated and hydrolyzed in the presence of nucleation seeds to obtain a precipitate. Subsequently, the precipitate was filtered, washed and dried to obtain titanium oxide. The specific surface area of this titanium oxide (by the BET method. The same applies hereinafter) was 290 m ² / g. next,
80 g of the titanium oxide base particles were dispersed in 1 liter of pure water, heated to a temperature of 40 ° C., and then dispersed in this dispersion.
An aqueous sodium hydroxide solution of N was added dropwise to adjust the pH of the dispersion liquid to 8. Then, under stirring, 1 mol of this dispersion liquid
110 ml of an aqueous zinc chloride solution of 1 / l and an aqueous solution of 2N sodium hydroxide were simultaneously added dropwise over 10 minutes while keeping the pH of the dispersion liquid at 8 to obtain a product. Subsequently, this product was filtered, washed, dried at a temperature of 120 ° C., and then crushed to obtain a titanium oxide powder (Sample A) of the present invention.

Example 2 Titanium oxide powder (Sample B) of the present invention was obtained in the same manner as in Example 1 except that 50 ml of the zinc chloride aqueous solution was dropped.

Example 3 Titanium oxide powder (Sample C) of the present invention was obtained in the same manner as in Example 1 except that 430 ml of the zinc chloride aqueous solution was dropped.

Example 4 Titanium oxide base particles 8 produced according to the method of Example 1
0 g was dispersed in 1 liter of pure water. After adding 15 g of zinc chloride powder to this dispersion, it was heated to a temperature of 40 ° C. Then, with stirring, a 2N aqueous sodium hydroxide solution was added dropwise to this dispersion for 10 minutes to adjust the pH of the dispersion to 8 to obtain a product. The product was subsequently filtered, washed, dried at a temperature of 120 ° C. and then crushed to obtain a titanium oxide powder of the present invention (Sample D).

Example 5 Titanium oxide base particles 8 produced according to the method of Example 1
0 g was dispersed in 1 liter of pure water. After adding 8.9 g of sodium hydroxide to this dispersion, it was heated to a temperature of 40 ° C. Then, with stirring, 110 ml of a 1 mol / l zinc chloride aqueous solution was added dropwise to this dispersion over 10 minutes to finally adjust the pH of the dispersion to 8 to obtain a product. The product was subsequently filtered, washed, dried at a temperature of 120 ° C. and then crushed to obtain a titanium oxide powder of the present invention (Sample E).

Example 6 1 liter of a 1 mol / l titanium tetrachloride aqueous solution was heated and hydrolyzed in the presence of nucleation seeds to obtain a titanium oxide precipitate. (Note that the titanium oxide precipitate was filtered, washed, and dried and had a specific surface area of 160 m ² / g.) The dispersion liquid of the titanium oxide base particles thus obtained was heated to 40 ° C. After the adjustment, a 2N sodium hydroxide aqueous solution was added dropwise to this dispersion to adjust the pH of the dispersion to 8. Then, with stirring, 110 ml of a 1 mol / l zinc chloride aqueous solution and a 2N aqueous sodium hydroxide solution were simultaneously added dropwise to this dispersion for 10 minutes while maintaining the pH of the dispersion at 8 to obtain a product. The product was filtered, washed, dried at a temperature of 120 ° C. and then crushed to obtain a titanium oxide powder of the present invention (Sample F).

Comparative Example 1 1 liter of a 1 mol / l zinc chloride aqueous solution was heated to a temperature of 40 ° C., then a 2N aqueous sodium hydroxide solution was added dropwise over 100 minutes with stirring to adjust the pH of the aqueous solution to 8. I got a thing. The product is filtered, washed and 120 ° C.
The powder was dried at a temperature of 1, and then crushed to obtain a hydroxide powder of zinc (Sample G).

Comparative Example 2 Titanium oxide obtained by the method of Example 1 and not treated with zinc chloride was used as sample H.

In each of Examples 1 to 6, the precipitate was filtered and washed relatively quickly, and the titanium oxide powder after drying was easily disentangled and crushed easily. .

Samples obtained in Examples and Comparative Examples (A to
Table 1 shows the specific surface area of H) and the adsorption rate of malodorous gas. The malodorous gas adsorption rate of the sample was measured by the following method. First, trimethylamine, methyl mercaptan, and hydrogen sulfide were diluted with nitrogen gas to about 1000 ppm. Next, 1 liter of the above-mentioned dilution gas was introduced into a polyester bag containing 0.1 g of the sample, which was sealed and left for 5 hours. After that, the concentration of the malodorous gas remaining in the bag was measured with a gas chromatograph or a gas detector tube, and the adsorption rate was calculated from the concentration of the introduced diluent gas.

[0021]

[Table 1]

Example 7 150 ml of a 1 mol / l titanium tetrachloride aqueous solution was added at 40 ° C.
The mixture was heated to the temperature of 4 ° C., and then a 4N sodium hydroxide aqueous solution was added dropwise over 10 minutes with stirring to adjust the pH of the aqueous solution to 3 to obtain a titanium oxide precipitate. The titanium oxide base particle dispersion liquid thus obtained was stirred for 3 m.
50 ml of an ol / l zinc chloride aqueous solution, 36.8 g of sodium orthosilicate and a 4N aqueous sodium hydroxide solution were simultaneously added dropwise over 10 minutes while maintaining the pH of the dispersion liquid at 10 to obtain a product. The product is filtered, washed and
It was dried at a temperature of 20 ° C. and then crushed to obtain a titanium oxide powder of the present invention (Sample I).

Example 8 In Example 7, 225 ml of an aqueous solution of titanium tetrachloride,
Treatment was carried out in the same manner as in Example 7 except that the amount of the zinc chloride aqueous solution was 75 ml and the amount of sodium orthosilicate was 9.2 g.
A titanium oxide powder (Sample J) of the present invention was obtained.

Example 9 A titanium oxide powder (Sample K) of the present invention was obtained by the same procedure as in Example 7 except that sodium orthosilicate was not added.

Table 2 shows the results of measuring the specific surface area and the malodorous gas adsorption rate of the samples (I to K) obtained in the examples in the same manner as described above. These samples are excellent in the adsorption rate of the malodorous gas, and it can be seen that they are preferable as the white deodorant. Next, 1 g of each of these samples was dispersed in 100 ml of a 0.01 N hydrochloric acid aqueous solution and 100 ml of a 0.01 N sodium hydroxide aqueous solution, and the mixture was stirred at a temperature of 40 ° C. for 3 hours, and the supernatant thereof was collected. The amount of zinc ions present in the solution was measured by optical emission spectrometry. The results are shown in Table 3. It can be seen that Samples I and J have similar solubilities to the alkaline aqueous solution, but are less soluble to the acidic aqueous solution than Sample K.

[0026]

[Table 2]

[0027]

[Table 3]

Comparative Example 3 100 ml of a 1 mol / l zinc chloride aqueous solution and 1 mol / l
1 ml of titanium tetrachloride aqueous solution (900 ml)
The mixture was heated to a temperature of 0 ° C., and then 4N aqueous sodium hydroxide solution was added dropwise at a rate of 10 ml / min under stirring to adjust the pH of the mixed solution to 8 to obtain a product. The product is filtered,
It was washed, dried at a temperature of 120 ° C., and then crushed to obtain a powder of titanium oxide and a hydroxide of zinc (Sample L).

Samples obtained in Examples and Comparative Examples (A,
The photocatalytic decomposition of malodorous gas by L) was investigated. First, 0.1 g of each sample was dispersed in 5 ml of ethanol, and then these dispersions were poured into a petri dish having a diameter of 8.6 cm and dried at a temperature of 70 ° C., and the sample was uniformly placed on the bottom of the petri dish. These petri dishes were placed in a plastic closed container (internal volume of about 8 liters) containing 4W black light, and acetaldehyde and methyl mercaptan were injected therein. Then, after leaving it in the dark for 2 hours, a black light was turned on to perform a photocatalytic reaction, and a change in the concentration of the malodorous gas in the closed container was measured by a gas chromatograph. The light irradiation intensity is 310 to 400n.
The light having a wavelength of m was about 1 mW / cm ² . The photocatalytic decomposition of acetaldehyde is shown in FIG. 1, and the photocatalytic decomposition of methyl mercaptan is shown in FIG. Table 4 shows the results of the photocatalytic reaction rate obtained from the slope of the straight line when the black light in FIGS. 1 and 2 is on.

[0030]

[Table 4]

[0031]

INDUSTRIAL APPLICABILITY The titanium oxide powder of the present invention in which zinc oxide is supported on titanium oxide substrate particles is useful for pigments, catalysts, catalyst carriers, adsorbents and the like. In particular, it excels in deodorizing performance of malodorous gases such as ammonia, methyl mercaptan, hydrogen sulfide, trimethylamine, methyl sulfide, and acetaldehyde, and is suitable as a white deodorant for sanitary articles such as paper diapers and sanitary napkins that come into direct contact with the human body. Further, the titanium oxide powder of the present invention in which the oxides of zinc and silicon are supported on the base particles of titanium oxide has a small amount of dissolved zinc oxide, and is excellent in deodorizing performance of malodorous gas, Particularly, it is suitable as a white deodorant for sanitary items such as paper diapers and sanitary napkins that come into direct contact with the human body. Further, the titanium oxide powder of the present invention can remove harmful substances rapidly and efficiently by a photocatalytic reaction, and is therefore extremely useful as a deodorant for not only industrial use but also general household use. Further, the harmful substance removing agent containing the titanium oxide powder of the present invention is highly safe, has a wide range of applicable harmful substances, and does not pollute the environment even when discarded, and therefore is extremely useful industrially. Is. The method of the present invention can easily obtain titanium oxide powder of stable quality,
In addition, it is easy to manufacture, the filtration and washing of the product during the manufacturing process are relatively quick, the powder after drying is easily loosened, and it is easy to pulverize, which is very useful industrially. is there.

[Brief description of drawings]

FIG. 1 is a graph showing the experimental results of photocatalytic decomposition of acetaldehyde. FIG. 2 is a graph showing the experimental results of photocatalytic decomposition of methyl mercaptan.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Satoshi Mukai 2-3-1, Nishi-Shibukawa, Kusatsu-shi, Shiga Ishihara Sangyo Co., Ltd. Central Research Laboratory

Claims (12)

[Claims] 1. A titanium oxide as a base material of titanium oxide containing zinc oxide obtained by neutralizing a zinc compound with a water-soluble alkali compound of an alkali metal or an alkaline earth metal.
On the other hand, the molar ratio of Zn is Ti: Zn = 9.9: 0.1.
Titanium oxide powder carrying an amount of ˜5: 5. 2. A titanium oxide substrate particle containing zinc and silicon oxides in a molar ratio of Ti: Zn = 9.9: 0.1 to 5: 5 as Zn relative to Ti of the substrate, and Molar ratio of Zn to Zn of zinc oxide is Zn: Si = 9:
Titanium oxide powder carrying an amount of 1 to 0.1: 9.9. 3. The titanium oxide powder according to claim 1, which has a specific surface area of 100 m ² / g or more. 4. The molar ratio of Ti: Zn is 9.5: 0.5.
The titanium oxide powder according to claim 1 or 2, which is 7: 3. 5. A water-soluble alkali compound of an alkali metal or an alkaline earth metal and a zinc compound are added to a dispersion liquid of titanium oxide base particles so that the zinc compound is dispersed in the dispersion liquid of titanium oxide base particles. A method for producing a titanium oxide powder in which titanium oxide base particles carry an oxide of zinc, and the resulting product is fractionated and dried. 6. A zinc compound, a silicon compound and a neutralizing agent are added to a dispersion liquid of titanium oxide base particles to neutralize the zinc compound and the silicon compound in the dispersion liquid of titanium oxide base particles. Then, the obtained product is fractionated and dried to produce a titanium oxide powder in which titanium oxide substrate particles carry oxides of zinc and silicon. 7. A deodorant comprising the titanium oxide powder according to claim 1. 8. A harmful substance removing agent which contains the titanium oxide powder according to claim 1 and decomposes a harmful substance by a photocatalytic reaction. 9. A deodorizing agent containing the titanium oxide powder according to claim 1, which decomposes an odorous gas by a photocatalytic reaction. 10. A deodorant comprising the titanium oxide powder according to claim 2. 11. A harmful substance removing agent, which comprises the titanium oxide powder according to claim 2 and decomposes a harmful substance by a photocatalytic reaction. 12. A deodorant containing the titanium oxide powder according to claim 2, which decomposes an odorous gas by a photocatalytic reaction.