KR102048839B1 - Method of preparing barium titanate - Google Patents

Abstract

Disclosed is a method for producing barium titanate. The disclosed method for producing barium titanate is a step of injecting a reaction material containing barium and titanium into a reactor, mixing at the molecular level in the reactor (S10), and chemically reacting the reaction material in the reactor. Reacting (nucleating) crystal nuclei by chemical reaction (S20), aging the crystal nuclei by primary heat treatment (S30), and subjecting the mature nuclei to secondary heat treatment (calcination), barium titanate powder Obtaining (S40), and crushing the barium titanate powder (S50).

Description

Method of preparing barium titanate {Method of preparing barium titanate}

Disclosed is a method for producing barium titanate. More specifically, titanic acid comprising injecting a reaction material comprising barium and titanium into a reactor, mixing at the molecular level, and chemically reacting to produce nucleating crystals. A method for producing barium is disclosed.

Barium titanate (BaTiO ₃ , hereinafter referred to as BT) is a material used as an insulating layer in a multilayer ceramic capacitor (MLCC).

BT used in MLCC is gradually changing the synthesis technology from the general hydrothermal method to the subcritical hydrothermal method as the demand for particle size and crystallinity increases. However, the subcritical hydrothermal method is performed under high temperature (220-280 ° C.) and high pressure (0.5-13 MPa), and thus requires a reactor made of a special material that withstands strong base reactants in raw materials, utilities, and subcritical conditions. Compared with the manufacturing method of barium titanate, the manufacturing cost is very high, so it is difficult to secure price competitiveness in mass production.

One embodiment of the present invention comprises the step of injecting a reaction material containing barium and titanium into the reactor to mix at the molecular level (nucleating) by chemical reaction (mixing at the molecular level) and chemical reaction (chemical reaction) It provides a method for producing barium titanate.

One aspect of the invention,

Injecting a reaction material comprising barium and titanium into a reactor and mixing at the molecular level in the reactor (S10);

Chemical reaction of the reaction material in the reactor to generate nucleating crystals (S20);

Aging the crystal nuclei by primary heat treatment (S30);

Performing a second heat treatment (calcination) on the aged crystal nucleus to obtain barium titanate powder (S40); And

It provides a method for producing barium titanate comprising the step (S50) of disintegrating the barium titanate powder.

The chemical reaction may be an acid group reaction.

The reaction raw material may be injected into the reactor in the form of at least one of a solution form and a suspension form.

The reaction raw material may include an acid raw material and a basic raw material, the acid raw material may be injected into the reactor through a first raw material injection line, and the basic raw material may be injected into the reactor through a second raw material injection line.

The acidic raw material may include barium and titanium, and the basic raw material may include metal hydroxide.

The acidic raw material may include titanium, and the basic raw material may include barium.

The acidic raw material may include barium, and the basic raw material may include titanium.

The basic raw material may include barium and titanium, and the acidic raw material may include at least one compound of an inorganic acid and an organic acid.

The time (T _M ) required for mixing at the molecular level may be shorter than the time (T _N ) required for nucleation.

The T _M may be 10 to 100 μs, and the T _N may be 1 μm or less.

The internal temperature of the reactor may be maintained at 60 ~ 95 ℃.

The molar ratio (Ba / Ti) of barium and titanium in the reaction raw material may be 1.0 to 2.0.

The residence time of the reaction raw material in the reactor may be 1㎳ ~ 10s.

The reactor includes a chamber defining an inner space, a rotatable permeable packed bed disposed in the chamber and filled with a porous filler, and at least one raw material for injecting the reaction raw material into the inner space. It may be a high gravity rotating packed bed reactor having an injection line and a slurry outlet for discharging the slurry from the inner space.

Centrifugal acceleration of the permeable packed layer may be maintained at 10 ~ 100,000 m / s ² .

The first heat treatment may be performed for 5 to 10 hours at 100 ~ 250 ℃.

The method for producing barium titanate may further include the step (S35) of washing the aged crystal nucleus with a washing solution of pH 3.0 to 7.0 between the step (S30) and the step (S40).

The secondary heat treatment (calcination) may be carried out by raising the temperature to a final temperature of 700 ~ 900 ℃ at a temperature increase rate of 30 ~ 60 ℃ / min, and maintained for 1 to 18 hours.

According to an embodiment of the present invention, injecting a reaction material including barium and titanium into a reactor, mixing at the molecular level and chemical reaction to produce nucleating crystals. By providing a high crystallinity (c / a), uniform particle size distribution, there is little internal pores, there is little aggregate, barium titanate powder excellent in dispersibility can be obtained inexpensively to provide a method for producing barium titanate Can be.

1 is a cross-sectional view schematically showing a high gravity rotary packed bed reactor used in the method for producing barium titanate according to one embodiment of the present invention.
Figure 2 is a SEM photograph of the barium titanate powder prepared in Example 1 of the present invention.
3 is a SEM photograph of the barium titanate powder prepared in Example 2 of the present invention.
4 is a SEM photograph of the barium titanate powder prepared in Comparative Example 1. FIG.

Next, a method for producing barium titanate according to an embodiment of the present invention will be described in detail.

Method for producing a barium titanate according to an embodiment of the present invention is a step of injecting a reaction material containing barium and titanium into the reactor mixing at the molecular level in the reactor (S10), the reactor Chemical reaction of the reaction raw materials in the reaction (nucleating) to produce (nucleating) (S20), the primary heat treatment to the step of aging (S30), the matured crystal nucleus secondary heat treatment (Calcination) to obtain the barium titanate powder (S40), and the step of crushing the barium titanate powder (S50).

In this specification, "barium" means a barium compound, a barium atom, or a barium ion depending on a case, and "titanium" means a titanium compound, a titanium atom, or a titanium ion depending on a case.

In addition, in this specification, "molecular level mixing" means the level of mixing with which each molecule is mixed. In general, "mixing" can be divided into "macro-mixing" and "micro-mixing", macro mixing means mixing of the vessel scale (vessel scale), Micromixing is synonymous with mixing at the molecular level described above.

The reaction raw material may be injected into the reactor in the form of at least one of a solution form and a suspension form.

The reaction raw material may include an acid raw material and a basic raw material. In this case, the acidic raw material may be injected into the reactor through a first raw material injection line, and the basic raw material may be injected into the reactor through a second raw material injection line. Accordingly, the acidic raw material and the basic raw material are injected into the reactor through the first raw material injection line and the second raw material injection line, respectively, mixed at the molecular level in the reactor, and then subjected to a chemical reaction such as an acid group reaction to barium titanate. Will form crystal nuclei.

The acidic raw material may include barium and titanium. Specifically, the acidic raw material may include barium chloride and titanium chloride. The acidic raw material may be, for example, a mixture of aqueous BaCl ₂ solution or water suspension, and TiCl ₄ aqueous solution or water suspension. For example, the acidic raw material may be an aqueous solution or water suspension of BaCl ₂ and TiCl ₄ having a total concentration of 0.3 to 3 mol / L. In this case, the basic raw material may include a metal hydroxide such as NaOH and / or KOH. For example, the basic raw material may be an aqueous NaOH solution or an aqueous KOH solution having a concentration of 0.3 to 7 mol / L (eg, 0.3 to 3 mol / L).

In addition, the acidic raw material may include titanium, and the basic raw material may include barium. Specifically, the acidic raw material may include titanium chloride such as TiCl _4, and the basic raw material may include barium hydroxide such as Ba (OH) ₂ .

In addition, the acidic raw material may include barium, and the basic raw material may include titanium. Specifically, the acidic raw material may include barium chloride such as BaCl _2, and the basic raw material may include titanium hydroxide such as Ti (OH) ₄ .

In addition, the basic raw material may include barium and titanium. Specifically, the basic raw material may include barium hydroxide and titanium hydroxide. The basic raw material may be, for example, a mixture of an aqueous solution of Ba (OH) ₂ or a water suspension and an aqueous solution or suspension of Ti (OH) ₄ . In this case, the acidic raw material may include an inorganic acid and / or an organic acid such as HCl or acetic acid.

Such barium chloride, titanium chloride, barium hydroxide and titanium hydroxide can be inexpensive to reduce the manufacturing cost of barium titanate.

The chemical reaction may be an acid group reaction in which the acid and the base in the reaction raw material are reacted by one equivalent and lose their properties as an acid and a base.

The time (T _M ) required for mixing at the molecular level may be shorter than the time (T _N ) required for nucleation.

In the present specification, "T _M " means a time taken from the start of mixing until the composition of the mixture becomes spatially uniform, and "T _N " means that the rate of crystal nucleation is in equilibrium from the time at which crystal nuclei start to form. It means the time it takes to reach and produce seed at a constant rate.

As such, by adjusting T _M to be shorter than T _N , when the maximum mixing between molecules is made before the start of nucleation in the reactor, nanoparticle-sized BT particles having a uniform particle size distribution can be prepared. Specifically, the T _M is 10 ~ 100㎲, the T _N may be 1 은 or less. If the T _M is within the above range, a BT crystal nucleus having a uniform particle size and high crystallinity can be obtained at low cost. In addition, when the T _N is 1 Pa or less, an appropriate level of reaction occurs to obtain a high yield of BT crystal nuclei.

In the preparation of the BT crystal nucleus, the internal temperature of the reactor may be maintained at 60 ~ 95 ℃. If the temperature is within the above range, not only can the yield of BT crystal nuclei be secured at an appropriate level, but the adjustment of T _N is facilitated. In addition, the molar ratio (Ba / Ti) of barium and titanium in the reaction raw material may be 1.0 ~ 2.0. If the molar ratio Ba / Ti is within the above range, no secondary phase (ie, Ti-rich crystal phase or Ba-rich crystal phase) is produced.

The residence time of the reaction raw material in the reactor may be 1㎳ ~ 10s, for example, 10㎳ ~ 5s. When the residence time of the reaction raw material is within the above range (1㎳ ~ 10s), an appropriate level of reaction occurs, and the size of BT crystal nuclei becomes easy and economical.

1 is a cross-sectional view schematically showing a high gravity rotating packed bed reactor used in the method for producing barium titanate according to one embodiment of the present invention.

This high gravity rotary packed reactor 10 is a chamber 11 defining an interior space, a rotatable permeable packed bed disposed in the chamber 11 and filled with a porous filler 12a ( 12) raw material injection lines 14-1 and 14-2 for injecting the reaction raw material into the internal space; And a slurry outlet 15 for discharging the slurry from the inner space.

In addition, the reactor 10 may further include a gas outlet 16 for discharging gas from the internal space.

Porous filler 12a may contain titanium which is highly corrosion resistant. Specifically, the porous filler 12a may be titanium foam.

The permeable packed layer 12 is filled with a porous filler 12a therein and may transmit the reaction raw material injected into the reactor 10 in the form of a solution or a suspension, and may be rotated by the drive shaft 13. have. The centrifugal acceleration of the permeable filler 12 may be maintained at 10 ~ 100,000 m / s ² . If the centrifugal acceleration of the permeable packed layer 12 is within the above range, the reaction may proceed to an appropriate level or more.

Although the reactor 10 having the above configuration is operated under atmospheric pressure, the reaction raw materials can be mixed at the molecular level by high centrifugal force by controlling the rotational speed of the permeable packed bed 12, so that the reaction proceeds smoothly even at low temperatures. You can. That is, by uniformly mixing the reaction material of the fine droplets before the growth of the BT particles, it is possible to obtain a uniform and high crystallinity of BT crystal nuclei at low temperature.

The primary heat treatment serves to increase the crystallinity of the crystal nucleus and increase the particle size. The primary heat treatment can be carried out in a reactor different from the reactor, for example a batch reactor, a semi-batch reactor, or a plug flow reactor.

The first heat treatment may be performed for 5 to 10 hours at 100 ~ 250 ℃. When the temperature and time at which the first heat treatment is performed are within the above ranges, crystal nuclei having a suitable particle size and uniform particle size distribution and high crystal nuclei can be obtained.

The method for producing barium titanate may further include a step (S35) of washing the aged crystal nucleus with a washing solution of pH 3.0 to 7.0 between the step (S30) and the step (S40).

The washing step (S35) is a step of adjusting the molar ratio (Ba / Ti) of barium to titanium in the barium titanate to be finally synthesized. That is, the Ba / Ti molar ratio decreases as the number of times of washing increases.

The cleaning solution may be an aqueous solution of an acid such as acetic acid.

The washing step S35 may include a centrifugal separation process, a reslurry process, and a reduced pressure filtration process. For example, in the washing step S35, the supernatant is discarded by centrifuging the slurry containing the aged crystal nuclei (hereinafter referred to as “first slurry”), and then the lower layer liquid (this is referred to as “first lower layer liquid”). The first lower layer liquid was reslurried with an acetic acid aqueous solution to obtain a second slurry, and then the second slurry was centrifuged again to discard the supernatant liquid, which was then referred to as the "second lower layer liquid". The second lower layer liquid was reslurried with an acetic acid aqueous solution to obtain a third slurry, and then the third slurry was centrifuged again to discard the supernatant liquid. And the third lower layer liquid is reslurried with distilled water to obtain a fourth slurry, and then the fourth slurry is subjected to a process of filtration under reduced pressure.

The secondary heat treatment (calcination) of the step (S40) serves to further increase the crystallinity of the washed crystal nucleus and further increase the particle size. The secondary heat treatment (calcination) may be carried out in a reactor different from the reactor, for example an electric furnace.

The step of performing the secondary heat treatment (calcination) is also referred to as the "grain growth step."

The secondary heat treatment (calcination) may be performed by increasing the temperature from the initial temperature of 0 ~ 30 ℃ to the final temperature of 700 ~ 900 ℃ at a temperature increase rate of 30 ~ 60 ℃ / min. When the temperature increase rate and the final temperature during the second heat treatment (calcination) are within the above ranges, barium titanate having a uniform particle size distribution can be obtained as well as the necking between the synthesized barium titanate particles is reduced.

In the secondary heat treatment (calcination), the final temperature may be maintained for 1 to 18 hours.

The step S50 of disintegrating the BT powder (hereinafter referred to as the "BT powder disintegration step") may include a bead mill, an attribution mill, or a ball mill with a predetermined medium. It may be carried out by wet grinding using a grinder such as, or dry grinding using friction between the raw materials or friction with the grinder without using a medium such as a jet mill or a disk mill. It may also be performed by. The BT powder pulverization step (S50) is for resolving the interaggregation of barium titanate particles, after the wet pulverization additionally requires a drying process, but it is not necessary to use a specially limited equipment for drying. In the BT powder crushing step (S50), when the pulverization efficiency is too high, the particles are broken or chipped (chipping) to cause a large amount of fine powder, which is likely to lower the particle size distribution and crystallinity Therefore, the grinding strength can be reduced as much as possible to break only the necking of the particles without destroying the particles themselves.

When the BT powder disintegration step (S50) is performed by wet grinding, the disintegrated BT powder may be dried for 12 to 48 hours at a temperature of 50 ~ 200 ℃.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

Example

Example  One

(Reaction raw material preparation and nucleation step)

(1) A 4.5 mol / L NaOH aqueous solution was prepared.

(2) After preparing 0.75 mol / L BaCl ₂ aqueous solution and 0.5 mol / L TiCl ₄ aqueous solution, respectively, the two metal chloride aqueous solutions were mixed with each other. At this time, the molar ratio (Ba / Ti) of Ba and Ti in the mixed solution was 1.5.

(3) The reactor 10 of FIG. 1 was manufactured by itself. The specifications of the manufactured reactor 10 were as follows.

Permeable filler layer 12: stainless steel (316L) surrounded by polytetrafluoroethylene (PTFE), cylindrical with 140 mm inner diameter and 250 mm outer diameter

Porous filler (12a): Titanium foam, rectangular pores, pore size: 5mm x 5mm

(4) In order to manufacture BT nanoparticles, the drive shaft 13 of the reactor 10 is rotated to rotate the permeable packed bed 12 at a speed of 3000 rpm (centrifugal acceleration: 10,000 m / s ² ) while the reactor 10 ) Was maintained at 90 ° C.

(5) The NaOH aqueous solution prepared in the above (1) and the BaCl ₂ / TiCl ₄ mixed solution prepared in the above (2) were respectively injected into the first raw material injection line 4-1 and the second raw material injection line 4-2. Through the continuous injection at a flow rate of 65L / min into each of the reactor 10 through to obtain a BT crystal nucleus.

(6) The first slurry containing the prepared BT crystal nuclei was discharged to the slurry outlet 15.

(7) The total reaction time in the reactor 10 was 15 minutes.

(Maturation step by primary heat treatment)

The first slurry was added to a batch reactor and heat treated at 190 ° C. for 7 hours. As a result, a second slurry containing aged crystal nuclei was obtained.

(Cleaning stage)

The second slurry was centrifuged with a centrifugal separator to discard the supernatant, and the lower layer liquid (called the "first lower layer liquid") was collected. Thereafter, the first lower layer solution was reslurried with an acetic acid aqueous solution of pH 4, and then centrifuged with the centrifuge to obtain a second lower layer solution. Subsequently, the second lower layer solution was reslurried with an acetic acid aqueous solution of pH 4, and then centrifuged with the centrifuge to obtain a third lower layer solution. Thereafter, the third lower layer solution was reslurried with distilled water and filtered under reduced pressure. As a result, washed crystal nuclei were obtained.

(Grain growth step by secondary heat treatment (calcination))

The washed crystal nuclei were introduced into an electric furnace (WonJun, WonJun 01), and the temperature was raised from room temperature (about 25 ° C) to 800 ° C at a temperature increase rate of 30 ° C / min, and then maintained at 800 ° C for 3 hours. As a result, agglomerated barium titanate powder was obtained.

(Disintegration and drying stage)

The agglomerated barium titanate powder was wet pulverized with a 20 L horizontal beads mill (medium: deionized water) at a circumferential speed of 5 m / s (ie, 500 rpm). At this time, the wet disintegration was terminated when the D 50 of the barium titanate measured by a particle size analyzer (Malvern, mastersizer-2000) reached 0.45 to 0.47 μm. The BT slurry formed after the wet disintegration was dried in an oven at 120 ℃ for 24 hours. As a result, disintegrated barium titanate powder was obtained.

Example  2

4.5 mol / L aqueous KOH solution was prepared instead of 4.5 mol / L aqueous NaOH solution, 0.81 mol / L aqueous BaCl ₂ solution was used instead of 0.75 mol / L aqueous BaCl ₂ solution, and the first heat treatment temperature. The barium titanate powder disintegrated in the same manner as in Example 1 was obtained except that was changed from 190 ° C to 170 ° C and the final temperature of the secondary heat treatment (calcination) was changed from 800 ° C to 830 ° C.

Comparative example  One

Barium titanate powder was prepared using the subcritical hydrothermal method as described below.

(Reaction raw material preparation step)

Titanium isopropoxide was hydrolyzed to prepare Ti (OH) ₄ gel. Thereafter, HNO ₃ was added to the Ti (OH) ₄ gel to synthesize 1.2 mol / L of stable nano-TiO ₂ sol through peptization. In addition, Ba (OH) ₂ · 8H ₂ O was dissolved in distilled water at 80 ° C. in a nitrogen atmosphere to prepare 1.26 mol / L barium hydroxide solution.

(Crystal nucleation step)

The TiO ₂ sol was added dropwise to the barium hydroxide solution. As a result, a first slurry containing BT crystal nuclei was obtained. In this case, the total content of the barium hydroxide aqueous solution and the total content of the TiO ₂ sol added dropwise was adjusted so that the molar ratio of barium to titanium (Ba / Ti) is 1.05.

(Maturation and grain growth stage by heat treatment)

The first slurry was added to an autoclave (Youngsung Tech) and heat treated at 260 ° C. and 150 bar for 48 hours. As a result, a second slurry containing grain grown BT particles was obtained.

(Cooling and cleaning steps)

The second slurry was left to stand for 12 hours and cooled to room temperature (25 ° C). Thereafter, the cooled second slurry was first filtered under reduced pressure, and the obtained solid was mixed with distilled water and then filtered under reduced pressure. Subsequently, the obtained solid was mixed with distilled water and filtered under reduced pressure. As a result, agglomerated barium titanate powder was obtained.

(Disintegration and drying stage)

The agglomerated barium titanate powder was wet pulverized at a speed of 4 m / s (ie 400 rpm) with a 5 L horizontal bead mill (medium: DI water). The BT slurry formed after the wet disintegration was dried in an oven at 120 ℃ for 24 hours. As a result, disintegrated barium titanate powder was obtained.

Evaluation example

Evaluation example  1: synthesized BT Particle size evaluation

After measuring the particle diameters (D50, D99) of the BT synthesized in each of the above Examples and Comparative Examples (that is, disintegrated BT), D50 and D99 / D50 are shown in Table 1 below. Here, the particle diameters (D50, D99) is a long axis of the barium titanate particles using an image analysis program (ImagePro Plus ver 4.5 of Mediacybernetics, Inc.) after taking an image using a scanning electron microscope (SEM, Jeol JSM-7400F) The particle diameter was calculated from the average of short axis, and was obtained based on this particle diameter. The number of barium titanate particles measured was 500 or more. In the present specification, D50 means a particle size corresponding to 10% of the total volume when the volume is accumulated from the small particles by measuring the particle diameter, and D99 is 99% of the total volume when the volume is accumulated from the small particles by measuring the particle diameter. Means the particle size corresponding to.

Evaluation example  2: synthesized BT Evaluation of crystallinity (c / a)

Crystallinity degree (c / a) of BT synthesized in each of Examples and Comparative Examples was measured by XRD (D / Max 2000 series of Rigaku), and the results are shown in Table 1 below. Specifically, 2θ = 44.5 ~ 46 degrees (°) was analyzed by XRD analysis conditions of the speed of 2sec / step and step size of 0.02 at 40kV, 200mA. Then, after calculating the d-spacing values of the a-axis and c-axis of the crystal lattice, c / a of the BT particles was calculated as their ratio. The results are shown in Table 1 below.

Example 1 Example 2 Comparative Example 1 D50 (nm) 140 156 165 D99 / D50 1.41 1.49 1.9 c / a 1.0101 1.0102 1.0095

Referring to Table 1, the BT synthesized in Examples 1 and 2 has a smaller volume average particle diameter (D50) and a smaller particle size distribution (D99 / D50) than the BT synthesized in Comparative Example 1, thereby providing a uniform particle size distribution. The crystallinity (c / a) was found to be high.

Evaluation example  3: BT Surface evaluation

SEM images of the BT synthesized in each of the above Examples and Comparative Examples were taken and shown in FIGS. 2 to 4, respectively. 2 is an SEM photograph of the BT synthesized in Example 1, FIG. 3 is an SEM photograph of the BT prepared in Example 2, and FIG. 4 is an SEM photograph of the BT synthesized in Comparative Example 1.

2 to 4, the BT prepared in Examples 1 to 2 had a smaller particle size and a uniform particle size distribution than the BT prepared in Comparative Example 1.

Although preferred embodiments of the present invention have been described above with reference to the drawings and embodiments, these are merely exemplary, and various modifications and equivalent other embodiments are possible to those skilled in the art. You will understand. Therefore, the protection scope of the present invention should be defined by the appended claims.

10: high gravity rotary packed bed reactor 11: chamber
12: permeable filler layer 12a: porous filler
13: drive shaft 14-1, 14-2: raw material injection line
15: slurry outlet 16: gas outlet

Claims (16)

Injecting a reaction material comprising barium and titanium into a reactor and mixing at the molecular level in the reactor (S10);
Chemically reacting the reaction raw materials in the reactor in which the internal temperature is maintained at 60 ° C. to 95 ° C. to produce nucleating barium titanate crystals (S20);
Aging the crystal nuclei by primary heat treatment (S30);
Performing a second heat treatment (calcination) on the aged crystal nucleus to obtain barium titanate powder (S40); And
Disintegrating the barium titanate powder (S50),
The first heat treatment is a method for producing barium titanate is performed for 5 to 10 hours at 100 ~ 250 ℃. The method of claim 1,
The chemical reaction is an acid-based reaction method for producing barium titanate. The method of claim 1,
The reaction raw material is a method of producing barium titanate is injected into the reactor in the form of at least one of the form of a solution and a suspension. The method of claim 3,
The reaction raw material includes an acid raw material and a basic raw material, the acid raw material is injected into the reactor through a first raw material injection line, the basic raw material is prepared of barium titanate injected into the reactor through a second raw material injection line Way. The method of claim 4, wherein
Wherein said acidic raw material comprises barium and titanium, and said basic raw material comprises a metal hydroxide. The method of claim 4, wherein
Wherein said acidic raw material comprises titanium, and said basic raw material comprises barium. The method of claim 4, wherein
The acid raw material comprises barium, and the basic raw material is a method for producing barium titanate containing titanium. The method of claim 4, wherein
The basic raw material includes barium and titanium, and the acid raw material is a method for producing barium titanate containing at least one compound of an inorganic acid and an organic acid. The method of claim 1,
The time (T _M ) required for the molecular level of mixing is shorter than the time (T _N ) required for the production of nuclei. delete The method of claim 1,
A method for producing barium titanate in which the molar ratio (Ba / Ti) of barium and titanium in the reaction raw material is 1.0 to 2.0. The method of claim 1,
The reactor,
A chamber defining an interior space;
A rotatable permeable packed bed disposed in said chamber and filled with a porous filler;
At least one material injection line for injecting the reaction raw material into the internal space; And
A method for producing barium titanate, which is a high gravity rotating packed bed reactor having a slurry outlet for discharging the slurry from the internal space. The method of claim 12,
Centrifugal acceleration of the permeable packed layer is a method of producing barium titanate is maintained at 10 ~ 100,000 m / s ² . delete The method of claim 1,
The method of manufacturing barium titanate further comprises the step (S35) of washing the aged crystal nucleus with a cleaning solution of pH 3.0 ~ 7.0 between the step (S30) and the step (S40). The method of claim 1,
The secondary heat treatment (calcination) is a method of producing barium titanate is carried out by raising the temperature to a final temperature of 700 ~ 900 ℃ at a temperature increase rate of 30 ~ 60 ℃ / min, and maintained for 1 to 18 hours.

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