JPS5941929B2 - Manufacturing method of titanium glass fiber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing chinchy glass fibers useful as cation exchange agents, cation adsorbents, catalyst supports, and filter gas adsorbents.

It has been known that chikunya glass fibers are produced as a by-product under special conditions during crystal synthesis of chikunya or alkali metal titanates by hydrothermal methods using high-pressure vessels, flux methods, or solid phase reactions. There is.

However, in both cases, the amount is small and ranges from several μ to several 100 μ.
The disadvantage is that it is difficult to manufacture and utilize the fibers industrially.

The present invention has been made to overcome this drawback, and its purpose is to provide a method for industrially producing long-fiber chikunya glass fibers without using a high-pressure container.

The present invention is based on the general formula M20. nTi0□ (M is Na
, K, Rb or Cs, n represents 1 to 6)
To the alkali metal titanate shown in or the raw material mixture for its production, alkali metal molybdate M2Moo4 or alkali metal tungstate M2W is added as a flux.
04 (However, M represents the same thing as above.

), in molar percentage (raw materials converted as oxides), 5:
Distributed in the ratio of 95-50:50, this formulation was
00~13' Melt by heating at 00°C, grow crystals of the resulting melt to produce a fibrous alkali metal titanate single crystal, and then remove M2 in the single crystal with an acid aqueous solution.
It has been found that when extracting the zero component, long-fiber chikunya hydrate fibers are obtained, and that when dehydrated at a temperature of 200°C or higher and 500°C or lower, chikunya glass fibers can be easily obtained.

The present invention was completed based on this knowledge.

As a raw material for the titanium component used in the present invention, titanium oxide is most preferable because it is easily available, but titanium compounds that produce titanium oxide by heating can also be used.

As titanium oxide, it is desirable that it easily react with an alkali metal component, and therefore an anatase type titanium oxide is preferable.

The alkali metal components used in the present invention include K,
Oxides of alkali metals such as Na, Rb, or Cs, and compounds that generate oxides when heated.

For example, KOH, NaOH, R1>OH, CsOH.

K2CO3, Na2CO3, Rb2CO3, KHCO3
.

Examples include NaHCO3=RbHCOa, CsHCO3, and the like.

The titanium component and the alkali metal component are combined into M2O, nT
i03 (where n is 1 to 6) is mixed in a proportion to produce a manufacturing raw material mixture.

Moreover, an alkali metal titanate having this composition can also be used in the same manner.

As a component of the alkali metal molybdate or alkali metal tungstate used as the flux in the present invention, each acid salt of Na, Rb or Cs is used.

However, a mixture of an alkaline component and MoO3 or WO3 may also be used.

These fluxes have the effect of promoting the production of single-crystalline fibers, and long fibers can only be obtained by their presence.

The larger the amount of flux mixed in, the greater the effect, and the composition range that allows long fibers to be produced quickly with good yield is the molar percentage of alkali metal titanate:flux (calculated as raw materials as oxides): 5 = 95 to 50:50. It is.

Furthermore, since the alkali metal tungstic acid or molybdic acid has a low melting point and low vapor pressure, the flux gas does not volatilize when heated and melted, so that it does not become a source of pollution.

Furthermore, since they are easily dissolved in water, the produced fibers can be easily separated, and the basicity of the melt can be adjusted by changing the mixing ratio of the M20 component and MoO3 or WO3, and by changing n. It has excellent effects such as the ability to easily obtain compositions with different n values.

The resulting blend is heated at 800-1300°C to form a melt.

If the melting temperature of the compound is lower than 800°C, the flux will solidify, and if it exceeds 1300°C, the flux component will volatilize, changing the flux composition and changing the basicity of the melt to the value of n. It is necessary to melt at 800-1300°C because of the influence.

The fibrous crystalline material can be produced from the melt by a slow cooling method, a Franks evaporation method, a temperature difference method, two local cooling methods, or a combination thereof.

The slow cooling method can be carried out by slowly cooling the melt to a temperature of 700 to 1000°C.

An alternative method is to evaporate the flux or create a humidity difference between the top and bottom of the crucible.

A method of blowing air onto the bottom of the crucible, a method of locally cooling the crucible by bringing it into contact with a material to be cooled, etc. can be performed.

The cooling rate affects the length of the fibers, and the slower the cooling, the more likely they are to become long fibers.

Scoop up the obtained fibrous product with a wire mesh, or
Separate it from the flux by draining only the molten liquid or dissolving the flux in water or hot water, and wash thoroughly with water or hot water.

Next, the fibrous product is treated with an aqueous acid solution such as a mineral acid or an organic acid, preferably an aqueous hydrochloric acid solution to extract the M20 component.

Although it can be extracted with water, it requires an extremely long period of time and is therefore industrially disadvantageous.

If this extraction is performed rapidly, the M20 component only in the surface portion will be extracted, and the M20 component in the core portion will not be sufficiently removed.

Therefore, it is desirable to extract it over a certain amount of time.

The dilute acid aqueous solution may be used after being heated to a temperature below its boiling point, and operations such as stirring and circulation may be performed.

By extracting the M20 component, T I 02 ,
A chikunya hydrate fiber having a composition of n R20 (n is 1 to 6) is obtained.

This chikunya hydrate fiber retains the original alkali metal titanate skeleton structure, and the alkali metal ions are H or H.
It is a crystalline substance with a structure in which + is substituted with 30+ ions, and has swelling and dehydration properties, as well as excellent ion exchange properties for polyvalent cations, etc.
It also has metal adsorption properties.

It can also be used as a carrier for catalysts, and as a filter for medicines or foods.

Further, when this is heated and dehydrated at a temperature of 200° C. or higher and 500° C. or lower, chikunya glass fibers are obtained.

The temperature of this heating and dehydration is in the stable range of chikunya glass.

It is necessary that the temperature is 200°C or higher and 500°C or lower.

The resulting chikunya glass fibers are amorphous and have active adsorption capacity.

Although it lacks selectivity in adsorption capacity compared to crystalline chikunya hydrate fibers, it is chemically stable and does not contain water, making it suitable not only for adsorption from aqueous solutions but also as an adsorption purifier and filter for waste gases. .

The method of the present invention has the effect of easily producing a large amount of long fiber chirpy glass fibers that are amorphous and can be effectively used for various purposes such as adsorption.

Example 1 TiO2 (anatase type) and 2CO3 powders were mixed at a molar ratio of 4:1.

2MoO4 as a flux was added to this in a molar percentage of 10:90 and mixed well.

Fill 90 g of the blend into a 100 TLl platinum crucible,
It was heated and melted at 1100°C using a siliconite electric furnace.

This melt was slowly cooled to 800°C at a rate of 4°C/h,
Fibrous crystals were obtained.

The obtained fibrous crystals were taken out from the crucible by dissolving the flux with water.

After washing with water and drying, the weight was measured and the yield was 98%.
As a result of powder X-ray diffraction analysis, all 2Ti4o
It was phase 9.

The fiber diameter is 0.01-0.1mm, and the average length is 3mr.
The maximum length of L and the largest dog was about 10 mm.

Next, this fiber was dissolved in IN-H (1001 nl in 1 aqueous solution).
After extracting 20 components while stirring for about 1 hour, the fibers were washed with water and air-dried to obtain chikunya hydrate fibers.

Identification of this chikunya hydrate fiber by powder X-ray diffraction showed a complex diffraction pattern.

This is presumed to be a water-containing phase that originally had a 2Ti,09 phase skeleton structure and K+ ions were substituted with H ions or H30+ ions.

This chikunya hydrate fiber exhibits swelling and dehydration properties, and
It was reversible at temperatures below 0°C.

Next, the obtained chikunya hydrate fiber was heated and dehydrated at 450°C to obtain chikunya glass fiber.

This chikunya glass fiber did not lose its hygroscopicity or water absorption properties, nor did it exhibit swelling or dehydration properties.

Claims (1)

[Claims] 1 General formula M2O-nTt02 (where M is Na
eK, Rb or Cs, n represents 1 to 6) or a mixture of its manufacturing raw materials, and an alkali metal molybdate M2 as a flux.
MOO4 or alkali metal tungstate M2W04
(However, M represents the same thing as above) in molar percentage (calculated as raw material as oxide): 5:95 to 50:
The mixture is heated and melted at 800 to 1,300°C, and the resulting melt is crystallized by a crystal growth method to produce a fibrous alkali metal titanate single crystal, and then mixed with an acid aqueous solution. Extract the M20 component of the single crystal with T
iO2, nH2O (n represents 1 to 6) as a chikunya hydrate fiber, and then the chikunya hydrate fiber was
A method for producing chikunya glass fiber, which comprises heating and dehydrating at a temperature of 500°C or higher. 2. Crystal growth of the melt is performed by heating the melt to 700-1000
The manufacturing method according to claim 1, which is carried out by slow cooling to a temperature of .degree. 3. The manufacturing method according to claim 1, wherein the crystal growth of the melt is carried out by evaporating a flux component. 4. The manufacturing method according to claim 1, wherein the crystal growth of the molten material is performed by providing a temperature difference between the upper and lower sides of the crucible or by blowing air to the bottom of the crucible. 5. The manufacturing method according to claim 1, wherein the crystal growth of the melt is carried out by bringing a cooling substance into contact with it to locally cool it.