JPS63195111A - Synthesis of fluorine mica clay - Google Patents

Abstract

PURPOSE:To make it possible to produce a product having a small amount of impurities and excellent uniformity in melting method, by using precipitate obtained by reaction between aqueous solutions or organic solvent solutions containing constituent elements of fluorine mica clay. CONSTITUTION:One or more substances which are soluble in water or organic solvents and contain one or more of an alkaline (earth) metal, Al, iron, Co, Ni, Mn, Zn, copper, Cr, Si, Ge and B and one or more fluorine compounds which are soluble in water or the organic solvents are dissolved in water or an organic solvent. Two or more raw material solutions are prepared, blended and reacted to form slightly soluble precipitate, which is separated and dried. The dried precipitate is heated at 400-1,400 deg.C to give a product shown by the formula. In the formula, X is one or more cations of alkaline (earth) metal; Y is one or more cations of Mg, Al, iron, Co, Ni, Mn, Zn, copper Cr and Li; Z is cation of Si or Ge or cation wherein Si or Ge is partially replaced with Al, iron or B; number of coordination number of X, Y and Z are 12, 6 and 4, respectively.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is applicable to electrical insulating materials, inorganic sols, inorganic films, inorganic porous bodies, machinable ceramics, ion exchangers, catalysts, adsorbents, carriers, fillers, etc. The present invention relates to an applicable method for synthesizing non-swelling or swelling fluoromite-based clay.

[Conventional technology] Conventionally, this type of synthesis method includes SiO2, MgO.

MgFz, KtCOz, Ma2SiFs,
Solid raw materials such as Al2O3 are blended to have a predetermined composition, and the blended raw materials made by mixing and pulverizing these are heated to 1400°C to 1500°C and melted, and then cooled to form fluorinated mica clay. There is a melting method that precipitates crystals. This melting method is divided into two types, an external heat melting method and an internal heat melting method, depending on the heating method.

The external heat melting method is a method in which a crucible containing prepared raw materials is placed in a furnace and the crucible is heated from the outside with electricity, gas, etc. In addition, the internal heat melting method is used, for example, in Japanese Patent Publication No. 57-8784.
As shown in the publication, the blended raw materials are placed in a furnace into which a graphite rod connected to a graphite electrode is inserted so as to cover the entire graphite rod, electricity is applied to the graphite electrode to make the graphite rod generate heat, and the graphite rod is heated. In this method, after melting the raw materials around the molten raw material, the molten raw material itself also becomes a heating element to promote the melting of the surrounding raw materials.

Currently, the internal thermal melting method is mostly adopted industrially because of its high thermal efficiency.

[Problems to be Solved by the Invention] However, in both the external heating method and the internal heating method, the blended solid raw materials must be thoroughly mixed and pulverized using a ball mill, etc. in order to facilitate the melting of the blended raw materials. Moreover, the heating temperature required was as high as 1400° C. or higher, and the energy cost was high. Furthermore, fluorine volatilizes from the melt during melting, reducing the homogeneity of the melt.As a result, various impurities may eutectoid, and the resulting crystals may have irregular shapes and particle sizes. Ta.

In addition, the internal heat melting method is a batch method that repeats the process of inputting raw materials, heating process, and taking out the melt in a single furnace, which makes continuous production impossible. When taking out the molten material, it was necessary to break up the hard, near-molten layer around the molten material using an electric drill or the like. Furthermore, the internal heat melting method requires the removal of eutectoid impurities in the melt and unmelted raw materials mixed in when the melt is taken out, which poses the problem of a lot of troublesome work and poor production efficiency.

An object of the present invention is to provide a method for synthesizing fluobionite clay that has few impurities and has excellent homogeneity, which can be synthesized efficiently through a simple process, with low energy consumption, and at low cost. be.

[Means for Solving the Problems] As a result of extensive research to eliminate the various drawbacks of the above-mentioned conventional fluobionite clay synthesis method, the inventors of the present invention have developed the method of using a solid raw material as a starting material. By preparing an aqueous solution or an organic solvent solution containing the constituent elements of fluobionite clay, separating and drying the hardly soluble precipitate produced by the reaction between these solutions, it is easy to obtain extremely fine and homogeneous material. The present invention has been completed based on the fact that it is possible to obtain a blended raw material with excellent properties, and the subsequent heat treatment temperature can be lowered to a temperature lower than the melting point of the blended raw material.

That is, the present invention provides alkali metals and alkaline earth metals that are soluble in water or organic solvents.

Al, Fe, Go, Ni, Mn, Zn, C
One or more substances containing one or more elements selected from u, Cr, Si, Ge, or B and one or more F compounds soluble in water or an organic solvent are added to water or an organic solvent. a preparation step of preparing two or more raw material 4 solutions by dissolving;
a mixing reaction step of mixing and reacting the raw material solutions to produce a hardly soluble precipitate; a drying step of separating the precipitate from the raw material solution and drying it; and a drying step of drying the dried precipitate.
By heating at a temperature of 0°C to 1400°C, Xc+, t-s, o Y2 ~3 Z4 0
to F2 ""1 (1) A method for synthesizing a fluobionite clay, which includes a heating step to obtain a fluobionite clay.

In the above formula (1), X is one or more metal cations selected from alkali metals or alkaline earth metals; Y is Mg, Al, Fe, Co, Xi, Mn
.

l or 2 selected from Zn, Cu, Cr, or Li
The above metal cation; Z is a Si or Ge cation, or a part of Si or Ge is Al, Fe, or B
X has a coordination number of 12, Y has a coordination number of 8, and Z has a coordination number of 4.

The crystal structure of the fluorine matrix clay of the present invention is a stacked three-layer lattice in which an octahedral layer consisting of Y, oxygen, and F is sandwiched between two tetrahedral layers consisting of Z and oxygen. In order to compensate for the lack of positive charge in this three-layer lattice, X is coordinated as a living room ion between the three-layer lattice.

X is an alkali metal ion or an alkaline earth metal ion, but alkali metal ions, especially Li'', Na'',
K+ is a common cation.

Y is F4g24. A13+, Fe34;
Fe24. Co24. pij2+.

M n ” + Z n ” + Cu ” * Cr
"or Li+, but especially Mg", AI3+ or Li+ are common cations.

Z is Si'+ or Ge'+ cation, -nu is S
It is a cation obtained by replacing a part of i'' or Ge'+ with A13+, Fes+, or B3÷teat, but especially Si4+
or AI"" is a common cation.

By changing the combinations of X, Y, and Z mentioned above, many types of isomorphic substituents can be obtained. In addition, depending on the position of insufficient positive charge and the type of The property of attracting X, that is, swelling property, and the ion exchange property of exchanging X with other cations are imparted.

If the position of insufficient positive charge is in the central octahedral layer of the three-layer lattice, that is, Y, or if X is Li+ or Na+, which has a small ionic radius and strong hydration, the swelling and ion exchange properties will be poor. easily granted.

Examples of such swellable fluorine matrix clays include:
NaNgz, s 5i4011T F2 (sodium type tetrasilicon fluoromite), NaMgL 1SiJ
1o F2 (sodium taeniolite), Lil
Examples include ziMg@zzLi1/3Si40toF2 (lithium hectorite). In addition, examples of non-swellable fluorinated 11-based clays include 1, for example, KMgtS +s A I
O1°F2 (fluorine gold cloud 1), KMg2LiSi
+0toF2 (teniolite) or KMgt, s 5
Examples include i401o F2 (tetrasilicon fluorine cloud 11).

Starting materials and raw material solution preparation process> The starting materials of the present invention are soluble in water or organic solvents, and are alkali metals and alkaline earth metals.

Al, Fe, Co, old, Mn, Zn, Cu,
A substance containing one or more elements selected from Cr, Si, Ge, or B, and a fluorine compound soluble in water or an organic solvent, which is poorly soluble when the substance and the F compound are subjected to a liquid phase reaction. This produces a precipitate.

For this purpose, the substance and the F compound each have the property of forming a poorly soluble hydroxide upon hydrolysis, or that the substance and the F compound react with each other to form a sparingly soluble compound. It is desirable to choose.

The organic solvent is selected depending on the type of the substance or F compound to be dissolved. Specific examples of the organic solvent include alcohols, ketones, ethers, benzene, etc., but alcohols are particularly preferred from the viewpoint of being miscible with water and from the economic standpoint.

The substance will be explained in relation to X, Y, and Z in the formula (1).

Examples of water-soluble alkali metal compounds containing X in formula (1) include Na compounds, such as Na0)1.
Na2CO3, NaNO3, NaF, Na)lF2
In addition to inorganic compounds such as CH3COONa, HCOO
Organic compounds such as Na and NazCto 4 can be mentioned. Further, specific examples of combinations of Na compounds soluble in organic solvents and their organic solvents include Na0CHt-methanol,
Examples include NaCHxC0 (JCOCH3-acetone, etc.). All of these Na compounds react with other compounds such as Si compounds and F compounds to produce poorly soluble sodium silicate. Also, among the Na compounds, NaOH
, Na2COs is preferable because it exhibits alkalinity and has the effect of promoting hydrolysis of other components, such as Si, AI or M, and the compound. NaOCH3 is preferable for the same reason as mentioned above, since it decomposes into NaOH and methanol by hydrolysis and becomes alkaline.

Examples of water-soluble alkaline earth metal compounds containing Y of formula (1) include Mg compounds, such as Ng(N
(h'h, MgCl2. No aJnm such as MgSO4
In addition to Mg(CHtCOOh, Mg(HGOO)2
Organic salts such as Also, Mg soluble in organic solvents
Specific examples of combinations of compounds and their organic solvents include) Ig
(OCH3)2-methanol, MgCCfh C; 0C
HCOCHs)! -Acetone etc. All of these Mg compounds form sparingly soluble magnesium hydroxide by hydrolysis, and also form sparingly soluble magnesium fluoride by reacting with the F compound. In particular, Mg
(HCI3)2 is preferred because hydrolysis occurs without the addition of alkali.

Among the compounds containing Z in the formula (1), for example, the Sj compound is unstable in an aqueous solution and is easily hydrolyzed immediately, so it is desirable to use it as a solution in an organic solvent.

Specific examples of combinations of Si compounds soluble in organic solvents and organic solvents include S1cI4-benzene, (CHI)
2SiCh-1 thyl ether, Si (OC2HS
)4-Ethanol, 5i(C)l*cOcHcOcHz
) scI-HCI-acetone and the like. Note that among organosilicon compounds, many of them are liquid themselves, such as 5i(OC2HS)4.

In this case, it goes without saying that it can be used as a raw material solution without being dissolved in an organic solvent, and among the Si compounds, SOC2Ha)4 is preferred because it forms a dense precipitate.

A specific example of a fluorine (F) compound that is soluble in wood is HF.
, NH4F, NaHF2. NH4HF2.
Examples include NaF.

These F compounds react with Mg compounds to form sparingly soluble magnesium fluoride, and react with Ha compounds and S1 compounds to form sparingly soluble sodium silicofluoride.

Two or more raw material 1 solutions are prepared by dissolving the above substance and the above F compound in water or an organic solvent at room temperature and atmospheric pressure. Here, each raw material solution may be prepared so as to contain the above-mentioned substance and the above-mentioned F compound individually. Further, each raw material solution may be prepared to contain two or more of the above substances, two or more of the above F compounds, or the above substances and the above F compounds, as long as they do not react to form a poorly soluble compound.

The above-mentioned raw material solutions are mixed with each other in such a way that the composition of the hardly soluble precipitate produced when mixed has the desired chemical composition of the fluorinated mica clay represented by the above formula (1). and the amount is selected and prepared.

The amount of water in the total solvent when mixing the raw material solutions is
It must contain the minimum amount of water necessary for hydrolysis; if this water content is too large, the resulting precipitate will become a viscous gel containing a lot of water, which will require the precipitation separation process and drying process described below. Since the working efficiency decreases, it is desirable to reduce the amount of water as much as possible, and instead increase the coexistence and amount of an organic solvent.

Mixing reaction step> k: The raw material solutions prepared as described above are mixed at room temperature and atmospheric pressure. The mixing method may be a method of adding another raw material solution while stirring one raw material solution, or a method of adding each raw material solution to the organic solvent while stirring an organic solvent that has good affinity with the solvent in each raw material solution. It is also possible to add the solution in equal amounts at the same time, but the latter method has a lower
A more homogeneous precipitate is obtained.

In addition, when mixing the raw material solution, an acid catalyst or a salt catalyst may be added to accelerate the hydrolysis reaction if necessary. Catalysts for this include acetic acid, ammonia, etc., which dissipate by heating. Water etc. are suitable. Further, the acid catalyst or the base catalyst may be blended in advance into the raw material solution as long as it does not generate a hardly soluble precipitate.

When the raw material solutions are mixed by the above method, a sparingly soluble hydroxide is formed by hydrolysis, or a sparingly soluble compound is formed by a reaction between the substance and the F compound, thereby forming the desired fluobionite clay. X, Y required to
, a precipitate containing the elements Z and F is formed.

Drying process> Remove the precipitate by an appropriate method such as filtration or centrifugation. +1 Separated from liquid. The mother liquor may contain salts soluble in water or organic solvents, such as NH4Cl, which are by-produced during the reaction to form a precipitate. In this case, it is preferable to wash the precipitate several times with water or a mixed solvent of water and an organic solvent.
However, when an organic acid salt, an organic compound such as an alkoxide, a nitrate, or an ammonium salt is used as a starting material, there is no need to perform any particular washing because the stimulants are easily dissipated by the heat treatment described below.

The precipitate is dried under reduced pressure or atmospheric pressure at around 100° C. until the solution adhering to the surface of the precipitate is almost evaporated.

Heating process> Next, the dried precipitate is heated at 400 to 1400°C under atmospheric pressure.
A powder of fluorine-based clay can be obtained by heat treatment at a temperature of . If the heating temperature is less than 400°C, fluorine matrix clay will not be produced, and if the heating temperature exceeds 1400°C, the powder will begin to melt, impurities will be produced, and moreover, the volatilization of F will become more intense, both of which are undesirable. Although it is possible to synthesize fluorine matrix clay in a wide temperature range as described above, judging from the energy cost and the state of the crystals of the produced fluorine matrix clay, it is preferable to perform heat treatment at a temperature of 600 to 1000 ° C. Appropriate heat treatment time is about 1 to 10 hours. However, this heating temperature and heating time are mainly determined by the particle size of the desired fluorinated clay, and if the heating temperature is low or the heating time is short, a powder with a relatively small particle size can be obtained; Relatively large particle sizes are obtained at high temperatures or long heating times.

The heating furnace may be a Matsufuru furnace, or a tunnel kiln.
If the latter furnace is used, which may be a continuous firing furnace such as a rotary kiln, it is possible to synthesize in large quantities more efficiently.

In addition, the dried precipitate is once calcined at a low temperature of about 300°C to dissipate water and other dissipated substances in the precipitate, and then
If the calcined product is compacted by means such as pressure molding or granulation and then main firing is performed again at the above-mentioned temperature, a fluorine matrix clay with even better crystallinity can be obtained.

[Effects of the Invention] As mentioned above, according to the present invention, the conventional method requires a raw material mixing and pulverizing process with high energy cost and a melting process at high temperature due to the use of solid raw materials. Without using solid raw materials, raw material solutions containing the constituent elements of fluorinated matrix clay are mixed together, a hardly soluble precipitate is formed in a liquid phase reaction, and the slightly soluble precipitate is separated from the mother liquor, and the dried product is heated. The treatment has the excellent effect of being able to synthesize a fluorine matrix clay with few impurities and excellent homogeneity through a simple synthesis process, with low energy consumption, efficiently and at low cost.

[Examples] Next, in order to show specific embodiments of the present invention, the present invention will be explained in more detail using Examples, but the examples shown below are merely examples, and do not limit the technical scope of the present invention. It's not something you do.

<Example 1> KMgtS i3 al 01o F2 (Fudto phlogopite) synthesis: Mg(No3)2 8H200, 3 mo) and Al (N(h)3 8H200, 1 mole were added to water at room temperature.
Ethanol mixed solvent (water:ethanol = 1:1)3
0-order KOHO, which was dissolved to 00mM to prepare solution ①,
1 mole, 0.2 mole of NH4F.

and 50 mJl of 28% ammonia water to 250 mJZ of wood-ethanol mixed solvent (water:ethanol = l:1) at room temperature.
A solution ① was prepared by dissolving it in . Further, 140.4 mol of 5iC was dissolved in 300 mJl of a7atone at room temperature to prepare a solution (2).

Next, while stirring solution ■, add solution ■ and solution ■ to about 1
When they were added simultaneously at a dropping rate of 00 m/hr, precipitation occurred. The generated precipitate was separated from the mother liquor using a centrifuge, washed three times with a water-ethanol mixed solvent (water:ethanol mixed solvent), and dried at 80° C. under atmospheric pressure.

This dried product was heated at 850°C for 3 hours in an electric Matsufuru furnace to obtain Futo phlogopite KNg3S is At OtoF.
A powder of No. 2 was obtained.

X-ray diffraction revealed that the basal spacing d (001) was 9.6, and no products other than fluorine phlogopite were observed. The particle size of mica particles determined by electron microscopy is 8.3 to 24.
0 river ■ (average 15.3μ11), and the homogeneity was excellent.

20% calcium phosphate was added as a binder to this Futto phlogopite powder, and 30% calcium phosphate was added in an alumina ball mill.
After mixing, molding pressure 2000Kgf/am' under reduced pressure.
The sintered body was molded and then fired at a temperature of 1150° C. for 4 hours to obtain a disk-shaped sintered body with a thickness of about 2 mm. The volume resistivity of this sintered body at a relative humidity of 83% is 3.0. X10"
0cm, the breakdown voltage is 21.3KV/1ge,
It was shown that it is a good insulating material.

<Example 2> NaMg2. Synthesis of sSi+0toF2 (sodium-type silicon fluorine snow powder): Add 0.25 mol of metallic magnesium to 400 mfL of methyl alcohol at room temperature, heat at 80°C and reflux to form M
After preparing g(OCH3) 2-methanol solution, a solution (■) in which 5i(OC2)1s) + 0.4 mol was mixed with it and a solution (■) in which 20.1 mol of NaHF was dissolved in 200 mn of water at room temperature were added. Each was prepared.

While stirring 300 ml of methanol prepared separately, add about 100 ml of solution ■ at a dropping rate of 7 o'clock, and add solution ■.
were added at the same time at a dropping rate of about 50 meters per hour, resulting in precipitation. The generated precipitate was separated from the mother liquor using a centrifuge and then dried at 80° C. under atmospheric pressure. This dried product was once calcined at 300°C for 2 hours in an electric Matsufuru furnace, and then the calcined product was heated at 1000 Kgf/ under normal pressure.
Pressure molded with cl and made into a pellet shape.
Main firing was performed at 0° C. for 3 hours to obtain sodium type silicon fluorine mica Na M g 2JSi401oF2.

When this fired pellet was put into water, it swelled and became a sol. The proportion of mica solized at this time was 955% by weight of the total, indicating that little impurity was produced. This sol was dried at 40°C. The dry matter is
Linear diffraction confirmed that the base spacing d (001) was 12.3, indicating that it was of a -water layer type. Also, the particle size of the above Kumoha I particles measured using an electronic WJ microscope is 4.8~? ,l
3 gm (average 8.4 gm), and had excellent homogeneity.

Furthermore, 5.0 g of the above mica was added to 0.1N N1Ch aqueous solution 1
After stirring at room temperature for 20 hours,
It was separated from the mother liquor using a centrifuge, washed five times, and then dried at 80° C. under atmospheric pressure. Chemical analysis of the dried material revealed that it contained 4.3% by weight of Ni, as well as X! !
The diffraction nior base distance d (0'01) was widened to 14.7, indicating that it had ion exchange properties.

<Example 3> Li, zx Mgazs Litz3Si4o 1°F
Synthesis of 2 (lithium hectorite): Mg(CHx C00) 2.4H202,87 mol was added to a room temperature water-ethanol mixed solvent (water:ethanol = 1
: 1) A solution (■) was prepared by dissolving in 2000ml. Also, N) 14) 2 moles of IF was added to a room temperature water-ethanol mixed solvent (water:ethanol-1:1) 1000mM
A solution ① was prepared by dissolving it in . Then LiOH0,87
A solution (2) was prepared by dissolving 350 ml of mol and 28% ammonia water in 850 ml of methanol at room temperature. 5 more
i(OC28s) 44 mol and room temperature methanol 200
A mixed solution (■) of mJL was prepared.

While stirring solution (1), solutions (2), (2), and (2) were simultaneously added at a dropwise rate of 100 mfL/hour, respectively, and precipitation occurred. Most of the mother liquor was removed from the resulting precipitate using a filter press to form a cake, which was then dried at 80° C. under atmospheric pressure.

This dried material was heated to a temperature zone of 2 m at 500°C, then
Lithium hectorite was heated by passing it continuously through a tunnel kiln with a temperature zone of 0°C set at 4 m at a speed of 1 m/hour.
i1zsSi40 Ill F2 was obtained.

When this lithium hectorite was put into water, it became suspended in a sol state and exhibited swelling III properties.

This sol was reduced to about 5% sol using an evaporator at 50°C, and then spread on a glass plate with a smooth surface using the doctor blade method and allowed to dry naturally.
A sheet with a thickness of about 1110 gm was produced.

The light transmittance of this sheet at a wavelength of 580 nm was measured with a spectrophotometer and was found to be I/Io -78%. For comparison, a reprinted lithium hectorite synthesized by a melting method was subjected to the same sheeting treatment and the light transmittance was measured, and it was found that I/Io = 48%. That is, the fudonite clay synthesized according to the present invention has excellent homogeneity and compactness.

It can be said that good transparency is imparted when formed into a sheet.

'y,',: ;[',',;・ 1.1\C=y-continued Ichimasa": p'i (t1 game) 19863
July 7th Director of the Patent Office Kuro 11 Akio 3 Person making the amendment/Relationship with 19 cases Patent applicant Address 1-5-1 Marunouchi, Chiyoda-ku, Tokyo Name Mitsubishi Mining and Cement Co., Ltd. 4 Agent 7. Contents of the amendment (1) Page 7, line 19 of the specification “By changing the combination of the above X, Y, and Z”
The statement "by changing the combination of each ion in X, Y, and Z of L" is corrected.

(2) Specification page 1, line 11 to page 12, line ``...
・, NaMgLi5iJ to F2 (sodium taeniolite)" is replaced with [..., NaMgz LiSi+010 F2 (
Sodium taeniolite)” is corrected.

(3) In the first line of page 16 of the specification, the phrase "large particle size can be obtained" is corrected to "large particle size powder can be obtained."

(4) Page 18, line 8 of the specification It says "...is 3.6 people" [… is 8.8 people]” is corrected.

Claims (1)

[Claims] 1) an alkali metal that is soluble in water or an organic solvent;
Alkaline earth metals, Al, Fe, Co, Ni, Mn, Z
One or more substances containing one or more elements selected from n, Cu, Cr, Si, Ge, or B and one or more F compounds soluble in water or an organic solvent are combined in water or an organic solvent. a preparation step of preparing two or more raw material solutions by dissolving them in a solvent; a mixing reaction step of mixing and reacting the raw material solutions to produce a hardly soluble precipitate; and separating the precipitate from the raw material solution. A drying step of drying; X_0_. by heating the dried precipitate at a temperature of 400°C to 1400°C. ＿３＿～＿１＿． _0Y_2_～_3_Z_
4O_1_0F_2 A method for synthesizing fluoromica-based clay including a heating step to obtain fluoromica-based clay. However, X is one or more metal cations selected from alkali metals or alkaline earth metals; Y is Mg, Al
, Fe, Co, Ni, Mn, Zn, Cu, Cr, or L
One or more metal cations selected from i; Z is Si
or a Ge cation, or a cation in which a part of Si or Ge is replaced with Al, Fe, or B; X has a coordination number of 12, Y has a coordination number of 6, and Z has a coordination number of 4. . 2) The method for synthesizing fluoromica-based clay according to claim 1, wherein the substance and the F compound are hydrolyzed in a mixing reaction step to form a hardly soluble hydroxide. 3) The method for synthesizing fluoromica-based clay according to claim 1, wherein the substance and the F compound react with each other in a mixing reaction step to form a poorly soluble compound.