JPS6335419A - Production of spherical titanium oxide of hydrate type - Google Patents

Abstract

PURPOSE:To obtain the titled TiO2 nearly in a monodisperse system of submicron simply, efficiently and inexpensively, by treating H2O3 with a soluble Ti compound in an aqueous solution at an adjusted pH to form a specific complex and allowing the solution to stand or heating it. CONSTITUTION:In an aqueous solution adjusted to pH>=4, H2O2 is treated with a soluble Ti compound (e.g. TiCl4, etc.) to form a titanyl ion hydrogen peroxide complex. Then the solution containing the complex is allowed to stand at room temperature or heat-treated at about 40-80 deg.C to produce spherical TiO2 of hydrate type. The spherical TiO2 of hydrate type nearly in monodisperse system of submicron can be produced extremely simpler, at higher production efficiency and at lower cost than the conventional alkoxide method and molded TiO2 having high crystallizability nearly in a monodisperse system of submicron similar to that of the conventional alkoxide method is obtained from the prepared spherical TiO2 of hydrate type.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is directed to the production of water-use type spherical acid 1 used as a raw material for the production of titanium, a crystalline spherical acid used as a raw material for pigments, phi/ceramics, etc. This invention relates to a method for producing hititan.

(Prior Art) Conventionally, as a method for producing this type of water-use type spherical acid f-hititanium, Ti(OC6H7)4. Use of separate moisture jl k of titanium alkoxy r such as Ti(OC2H5)4, *
7 The alkoxy-r method is known, and by applying the 710#P-treatment of water-use type spherical titanium oxide, which is close to submicron monodisperse and obtained by the alkoxyr method, highly crystalline spherical, close to submicron monodisperse acid (yields hititane).

(Problems to be Solved by the Invention) In the case of the above-mentioned conventional alkoxy method, water-use type spherical titanium oxide cannot be obtained unless titanium alkoxy pon is closely divided into flow water decomposition at a dilute concentration. The counterfeiting is complicated, the production name is poor, and the liquid viscosity of titanium alkoxide is high, requiring the use of organic solvents such as propyl alcohol and alcohol, and the production cost is high because titanium alkoxide is expensive. If it is too high, it will be inconvenient.

(Ninth Means for Solving the Problems) The entire purpose of the present invention is to provide a method for producing water-use type spherical titanium oxide that eliminates the above-mentioned disadvantages. In an aqueous solution,
A titanyl ion hydrogen peroxide complex is formed by allowing arsenic peroxide to act on a soluble titanium compound, and the solution containing the complex is allowed to stand at room temperature or treated at 1 temperature.

The reason for adjusting the pH of the aqueous solution to 4 or higher is that if the pH is less than 4, even if hydrogen peroxide is applied to the titanium compound, the titanyl ion hydrogen peroxide complex will decompose at room temperature and the hydroxyl (This is because Hichimengel will precipitate out. Furthermore,
The more the pH moves towards the alkaline side, the more stable the ratio becomes.
To adjust the pH of the aqueous solution in which the titanyl ion peracid monoarsenic complex is obtained, use an alkali such as aqueous ammonia. use

Is hydrogen peroxide generally commercially available hydrogen peroxide solution? use

As the soluble titanium compound, for example, titanium compounds such as titanium trichloride, titanium tetrachloride, 1,000 titanyl sulfate, titanyl nitrate, and titanium hydroxide are used. If you want to obtain particularly high-purity water-use spherical titanium oxide, first perform water decomposition of the titanium compound, release the hydrous titanium hydroxide, and remove anions sufficiently by filtration and washing. , by allowing hydrogen peroxide to act on it.

The titanyl ion hydrogen peroxide complex obtained by acting on the above-mentioned peracid f arsenide completely soluble injected titanium f arsenic compound yields water-use type spherical acid r arsenic even if left for a long time at room temperature. ~
If you add zero-temperature treatment at about 80'C, water-use type spherical titanium oxide will kill insects in a short time. Further, if necessary, seeds of ultrafine particles or some mechanical i* are applied to start the precipitation reaction of water-use type spherical titanium oxide. - The precipitation reaction starts and continues without stopping until all the hydrogen peroxide complex is decomposed. The water-use type spherical titanium oxide at the bottom has a significantly small melting point, so raw fi51X is 100%
It is. The reason why the precipitated water-using acid f-hititanium becomes spherical is thought to be due to the homogeneous-core-center-bottom reaction structure. The obtained water-use type spherical acid [hisentan] is washed with water if necessary, and dried after separation.

In addition, 400 to 800
If heat treatment is performed at ℃, highly crystalline spherical titanium oxide of submicron anatase type that is close to monodisperse can be obtained.

(Example) Next, specific examples of the method for producing water-use type spherical acid f-hititanium of the present invention will be described together with comparative examples.

Example: Approximately 0.4 M titanium tetrachloride aqueous solution (Osaka Titanium R'7
Mu manufacturing $V 115 mtVc Shinsui 185 d & 7Jo
First, prepare an approximately 0.3M aqueous solution of titanium tetrachloride. Add reagent grade hydrogen peroxide solution (manufactured by Wako Chemical ■, H2O2111if 30 wt4') to this aqueous solution 17
d'fr7JrJE, I got a dark brown liquid. Furthermore, in this solution, reagent grade ammonia water (manufactured by Wako Chemical ■, Ammonia Crushed 928-30 wt%') 18mZ'! In addition to yellow δ, a clear aqueous solution was obtained. The pH at this time was 10. This aqueous solution was kept in a water bath at 50'C for 10 minutes to precipitate water-type spherical titanium oxide fine particles. When the t0 precipitated particles were observed with a total transmission type single-child microscope, it was found that they were obtained by the conventional alkoxy 2 method. Similarly, we were able to confirm that submicron, nearly monodisperse, spherical particles were obtained. Next, the precipitated fine particles were thoroughly washed with pure water, separated from the mother liquor using a centrifuge, and dried at room temperature.

After drying, conduct thermogravimetric analysis and differential thermal analysis of the precipitated fine particles.9. The obtained t7JO thermal reduction curve and differential thermal curve are shown in FIG. 1 as curves A and A', respectively. Incidentally, the obtained dry powder of water-use type spherical titanium oxide was calcined at 400° C. for 2 hours to obtain crystalline spherical titanium oxide. The obtained crystalline spherical titanium oxide was subjected to X-ray diffraction, and its X@ pattern is shown in FIG.

Comparative Example In the same manner as in the above example, an approximately 0.3 M titanium tetrachloride aqueous solution 200- was prepared, and 182 tR1 of pure water was added to the same reagent grade ammonia water 18- as described above to add 200 Jnl of dilute ammonia water. It was adjusted. The obtained adjusted ammonia water was gradually added dropwise to the above-mentioned four-base titanium aqueous solution with sufficient stirring to precipitate titanium hydroxide.
When the precipitated particles were observed under a total transmission electron microscope, they were not spherical particles but gel-like precipitates. Next, the gel-like precipitate was thoroughly washed with water, separated from the mother liquor using a centrifuge, and dried at room temperature. After drying, thermal analysis was carried out in the same manner as in the previous example, and the result 7 was used as a heat reduction curve and a differential 5-track 4i! Concave lines B and B' in Figure 3, respectively.
It was shown as In addition, in the following, the obtained T dry powder was heated at 500°C.
It was dawn at 2 o'clock. The obtained calcined product was subjected to X-ray diffraction, and its XllllIil diffraction pattern is shown in FIG.

In addition, the Kuna heat di curve and the differential heat curve obtained by thermal analysis of the dry material of water-use type spherical titanium oxide obtained by the conventional method of decomposing raw water of titanium furukogishi p are shown in Figure 5 as curves IY# C and C, respectively. ’. ! Is that a dry item? The crystalline spherical acid ratio titanium/Xiso diffraction pattern obtained by calcining at 430°C for 2 hours is shown in Figure 6.

From the heating loss curves, differential thermal curves, and X-ray diffraction diagrams of the Examples, Comparative Examples, and the conventional flukoxy P method shown in FIGS. Compared to the comparative example, highly crystalline anatase-type titanium oxide, which is equivalent to crystalline spherical titanium oxide obtained by calcining water-use type spherical titanium oxide using the conventional alkoxy 2 method, was obtained by heat treatment at a lower temperature than in the comparative example. It was confirmed that

(Effect of the invention) As described above, according to the method for producing water-use type spherical titanium oxide of the present invention, the PH? In an aqueous solution adjusted to a concentration of 4 or higher, a titanyl ion hydrogen peroxide complex is formed by acting on hydrogen peroxide, and the entire solution containing the complex is left to stand or heated. Therefore, compared to the conventional flukoxy method, water-use type spherical acid fHinatan 1R can be produced with near monodispersity of submicron scales with extremely ease, production efficiency, and low cost, and the obtained water-use type spherical acid fHinatan 1R can be produced. From titanium oxide, it is possible to obtain highly crystalline spherical titanium oxide with a submicron size close to monodispersity, similar to the conventional alkoxy V method.

[Brief explanation of the drawing]

FIGS. 1, 3, and 5 are thermal analysis W property diagrams of precipitates obtained in Examples of the present invention, Comparative Examples, and Conventional Examples, and FIGS. 2, 4, and 6, respectively. The figures are X-ray diffraction patterns of calcined winter precipitates. Patent Applicant Taiyo Yuden Co., Ltd. Figure 3; Kendo ('c) Kaikarikura (29)

Claims (1)

[Claims] Hydrogen peroxide acts on a soluble titanium compound to form a titanyl ion hydrogen peroxide complex in an aqueous solution whose pH is adjusted to 4 or more, and the solution containing the complex is left at room temperature or heated. A method for producing Japanese-type spherical titanium oxide.