JPS58140318A - Spherical basic aluminum sulfate and its manufacture - Google Patents

Abstract

PURPOSE:To manufacture novel spherical basic aluminum sulfate by adding a soluble sulfate to a soln. of a basic aluminum salt represented by a specified formula while keeping the soln. at a specified temp. CONSTITUTION:A soln. of a basic aluminum salt represented by a formula Al(OH)cXd (where X is a univalent anion, c+d=3 and 0.5<=c<=2.55) is kept at 50-90 deg.C, and a soluble sulfate is added to the soln. to obtain spherical particles of novel basic aluminum sulfate represented by a formula Al(OH)a(SO4)b.nH2O (where a+2b=3, 2.30<=a<=2.50, 0.25<=b<=0.35 and 0<=n<=10) or an aggregate of the particles. The sulfate is added at an addition rate at which addition time T required to make the molar ratio of SO4/Al in the soln. (3-c)/2 satisfies 0.5<= T<=12. The basic aluminum salt soln. is prepared by adding an alkali soln. to a soln. of an aluminum salt of a univalent anion by an amount required to adjust the molar ratio of OH/Al in the soln. to 0.5-2.55.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel basic aluminum sulfate and a method for producing the same, and provides a basic aluminum sulfate and a method for producing the same that have unique characteristics due to a previously unknown molecular structure. do.

In recent years, with the advancement of ceramic manufacturing technology, there has been an increasing demand for ceramic raw materials with excellent sinterability.

Even in alumina, a typical ceramic, the production of spherical particles with a sharp submicron particle size distribution was an important issue.

As a result of intensive research efforts in search of such an alumina raw material, the present inventor, Hiro, discovered new spherical particles of basic aluminum sulfate having an average particle size of 1 micron or less and a narrow particle size distribution, and developed the present invention. I was able to complete it.

It is generally known that alumina obtained by thermally decomposing aluminum sulfate has better sinterability than alumina produced from other salts. In this case, it is preferable to use basic aluminum sulfate because a large amount of 80s gas is generated when W aluminum is thermally decomposed and it is difficult to control the particle size to submicron particles.

However, with conventionally known methods, submicron particles cannot be obtained because crystalline basic aluminum sulfate inevitably has a large particle size. In addition, in the case of amorphous basic aluminum sulfate, generally 50 d
/ becomes an amorphous aggregate with a specific surface area of more than -
The secondary particle size was several hundred angstroms, which made it unsuitable as a raw material for alumina because it was too small, it was difficult to filter and wash, and high purity was difficult to obtain.

However, although the basic aluminum sulfate of the present invention is amorphous in X-rays, #1 is generally amorphous in primary particles.
It is a spherical particle with an average particle size of 1 micron, and has an extremely sharp particle size distribution, which is an excellent property never seen before.

Furthermore, since it has excellent filtration properties, it is easy to wash and can be obtained with high purity.

The composition of the basic aluminum sulfate of the present invention is expressed by the general formula %.In order to obtain the above general formula, first, the basic aluminum sulfate is thoroughly washed, and then dried using an appropriate method as necessary. and measure the weight. Next, this is dissolved in an acid, and At and 804 are quantified, for example, by chemical analysis 6: chelate titration method. Since the value of b can then be calculated, the value of a is then determined to satisfy the condition of a+2b=5.

The reason why such a means is used is that it is difficult to quantify OI, and it is customary to set the coefficients in a general formula so as to maintain electrical neutrality.

Now, if we calculate the values of a and b as above, we get AA(
A large amount of OH)a(Boa)b can be calculated.

Since this value multiplied by the At concentration in the sample and subtracted from the initially measured sample weight corresponds to nH2O, n can be determined by simple calculation.

In general, the value of n varies considerably depending on the drying state of the basic aluminum sulfate.

For example, when water is still floating after washing, n; 10~
8. When water no longer floats, n=7 to 6. Further, if washed with ethanol after washing with water, n=2 approximately, and if dried at 60° C. for 12 hours after washing with ethanol, n=1. If the drying temperature is further increased and the drying time is increased, the value of n gradually decreases, and after drying at 150° C. for 2 hours, n becomes approximately 0.

As will be described later, the water represented by nH2O has an extremely broad and almost amorphous X-diffraction pattern of the basic aluminum sulfate of the present invention, so it has not yet been determined that this water is crystal water. However, by analogy with the results of examining the change in crystallinity accompanying drying of the prismatic basic ii* aluminum shown in Comparative Example 1, we found that nH2O is simply adhering water in the case of the basic aluminum sulfate of the present invention as well. Rather, I think it is a type of crystalline water similar to zeolite water.

The shape of basic aluminum sulfate shown in the above formula,
Generally spherical with an average particle size of 0.1 to 1 μm,
Sometimes it has a slightly flat shape. In addition, secondary particles with an average particle diameter of generally 0.2 to 50 microns, particularly around 10 microns, may be generated due to aggregation of particles.
Even in such cases, it is often possible to redisperse the particles into submicron particles by a method such as 4I pulverization.

The basic aluminum sulfate of the present invention is cuxa
In powder X-ray diffraction using trout, it does not show any diffraction peak in the range of 2#=5 to 70'', and can be considered amorphous from an X-ray perspective.

Figure 2 and Figure 3 1 = show the powder Xl11 diffraction pattern using the CLIKa line of a typical basic aluminum sulfate of the present invention obtained in Example 1 described later.

Tuna 2 figure is before drying, iris 6 figure is 1 at 600 after washing with ethanol.
The measurements were taken on a sample that had been dried for 2 hours. In both of the diffraction patterns, no peaks were observed except for a slight --low, and the crystallinity was extremely low in terms of X-rays.

When the basic aluminum sulfate of the present invention is heated and dehydrated, it is dehydrated in the same manner as conventional aluminum sulfate and converted into alumina. The measurement results of DTA and TG vary slightly depending on the production conditions and drying conditions of the sample. and TGt-measurement results are shown. The temperature increase rate is 10C/min. As the temperature rises, first 30
A broad endothermic peak can be seen up to around 0°. This is due to the elimination of structural water and hydroxyl groups and is accompanied by a weight loss of about 5511O. The relatively sharp endothermic peak at 900-960 C is rounded off by the sulfuric acid leaving as 803 gas, with a weight loss of about 25%. Moreover, after this peak, it changes to r-alumina. Furthermore, 1180~
At 1250°C, an exothermic peak associated with r-+α phase transition is observed.

The reason why the basic aluminum sulfate of the present invention is more moldy than conventional basic aluminum sulfate or aluminum hydroxide is that the transition temperature to r-alumina is higher and the transition is faster. This is what happens.

Similarly, the specific surface area of the basic aluminum sulfate of the present invention is generally 5 to 35-/f when dried at 60C for 24 hours after washing with ethanol;
Those baked for 0 minutes are generally 20-60n//1A200
Those fired at C for 50 minutes generally have a power of 3 to 15 W//f.

Furthermore, the basic aluminum sulfate of the present invention exhibits unique chemical properties due to its production process.

Generally, conventional basic aluminum sulfate is produced by hydrolysis of aluminum sulfate. It is thought that such basic aluminum sulfate has a structure in which 804''-ions are bonded to the outer shell of a polymer in which AL'' ions are bridged by OH- ions. Therefore, when conventional basic aluminum sulfate is treated with a weak alkali, the 8042- ions in the outer shell are separated, and the original shape of basic aluminum sulfate is often destroyed at that time.

However, when the basic aluminum sulfate of the present invention is made alkaline, the spherical particles collapse and the substance usually dissolves and turns into a gel. This is thought to be because the basic aluminum sulfate of the present invention is produced in a form in which the 8042- ion exchanged with the -anion ion binds polynuclides produced by hydrolysis of the aluminum salt of the -anion. . In other words, when the basic aluminum sulfate of the present invention is treated with an alkali, the 5042- ion that binds the multiple nuclides is separated, but at that time, the multiple nuclides are temporarily separated and the particle shape is probably destroyed.

The basic ii*aluminum of the present invention having #HI properties as described above can be expressed, for example, by the general formula % formula % (6) (where X represents a monovalent anion, c + d = 3
It can be produced by adding a soluble sulfate to a basic aluminum salt solution expressed by +0.5≦C≦2.55 while maintaining the 5it- of the basic aluminum salt solution at 5o to 90C.

The basic aluminum salt represented by the above formula (11) can be produced by various methods, but the most preferred method is to prepare a monovalent anionic aluminum salt, such as aluminum chloride, aluminum nitrate, aluminum bromide, aluminum iodide. , aluminum citrate, aluminum acetate, etc., preferably aluminum chloride.

This is a method in which an alkali is added to an aqueous solution of aluminum, especially aluminum chloride. As an alkali,
Sodium hydroxide, potassium hydroxide, and ammonia slag are used.

The alkali has a molar ratio of OH/At in the solution of 0.5 to
It is preferable to add it so that it becomes 2.55, preferably in the range of 1.5 to 2.5. If it is less than the lower limit of the above range, the yield of basic aluminum sulfate obtained by adding a soluble sulfate in the next operation will be low. Exceeding the above is not preferable because the particle size of basic aluminum sulfate tends to increase and the particle size distribution tends to become broad.

It is preferable to add the alkali gradually while stirring to avoid gelation. If the rate of addition of alkali is increased, the pH will locally increase and some precipitation may occur. If such a precipitate occurs, stirring for a sufficient period of time will redisperse the precipitate and form a homogeneous solution. Furthermore, even if no precipitation occurs, it is desirable to continue stirring for a suitable period of time in order to stabilize the pH of the solution.

The above operations are usually carried out at room temperature, but they can also be carried out in a heated state. 19. The basic aluminum salt solution is preferably an aqueous solution as described above, but it may also be mixed with an organic solvent such as alcohol or acetone. tm of salt solution
BOa/
It is preferable to add so that the molar ratio of hL is larger than the value of (3-c)/2 (where C is the sign in general formula (6)). In particular, 10% from the value of (5-Q)72
It is desirable to add it so that it becomes larger than that. By doing so, the filterability of the obtained basic aluminum sulfate spherical particles and their aggregates is improved, and the precipitate of the basic aluminum sulfate can be easily separated and washed.

When the molar ratio of SOa/A4 is less than the value of (3-c)/2, some amorphous particles may be produced as a by-product, and the filterability may be deteriorated.

Also, the rate of addition of soluble sulfate is f3047A
The addition time T(
It is preferable to set the unit hour) to be in the range of 0.5≦T≦12, and more preferably in the range of 1≦T≦8. When the sulfate addition time T is below the lower limit of the above range, the particle size of the basic aluminum sulfate obtained increases, and in some cases, prismatic particles having an average length of about 15 microns may be produced. Generally, as the addition time T increases, the particle size of the basic aluminum sulfate spherical particles produced tends to become smaller, but when T exceeds the upper limit of the above range, the filterability of the produced precipitate deteriorates,
This is not preferable because it may partially form a gel.

Here, until the molar ratio of 8047At reaches the value of (3-C)/2, the molar ratio of S O < /A L becomes (5-
It does not necessarily mean that it is essential to add sulfate to a value equal to or greater than the value of C)/2. B
Even if sulfate is added only to the extent that the molar ratio of oa/At is less than the value of (3-c)/2, if 80a/AL
If it is added until the molar ratio of (!1-C)/2 is reached, the addition time T required to reach that value should be within the above range and at a rate that satisfies the addition. It is the meaning.

As mentioned above, it is important to keep the temperature of the basic aluminum salt solution at the time of adding the soluble sulfate at 50°C or higher and lower than 90°C, and in particular, it is important to keep it at 55°C or higher and lower than 80°C. . If the solution is lower than this, in addition to spherical particles, columnar or acicular particles with a length of about 10 microns, for example, will be produced.

Furthermore, if the liquid temperature is too high, a gel will form and the filterability of the precipitate will tend to deteriorate.

Here, as described above, the soluble sulfate is generally added in the form of an aqueous solution, but the temperature thereof does not necessarily have to be as strong as the temperature of the basic aluminum salt solution. However, when adding sulfate at a low temperature, even at room temperature, the temperature of the reaction solution may drop.
At this time, care must be taken to ensure that the temperature of the reaction solution does not deviate from the above temperature range.

In order to reduce the temperature change in the reaction solution upon addition of the soluble sulfate, it is desirable to heat the sulfate in advance to the same temperature as the basic aluminum solution, but this is not essential.

Regarding the concentration of the solution, the At concentration in the reaction solution (suspension) at the time when the soluble sulfate is finally added is 0.01 to 0.2 mol/l. It is desirable to do so under certain conditions. If the concentration is too low, it will be disadvantageous for industrial production, and if the concentration is extremely low, no precipitate may be formed. On the other hand, if ** is too high, there is a tendency for gelation to occur easily.

Now, according to the conditions described above, a soluble sulfate salt is added to the basic aluminum salt solution. After a while after starting to add the sulfate, the solution first becomes cloudy like a sol, then becomes increasingly cloudy, and finally becomes a milky white suspension. When this milky white suspension is allowed to stand still, it separates into a white precipitate and a supernatant.

This white precipitate is the basic aluminum sulfate of the present invention, and in order to separate it, known means such as centrifugation or filtration are employed.

If necessary, the particles are washed with water and/or an organic solvent such as alcohol, and then dried to remove the salt IJM2>k and obtain pure basic aluminum sulfate spherical particles and aggregates thereof.

However, the basic aluminum sulfate of the present invention has secondary particles having an average particle size of submicrons! Although they are ItM spherical particles, they generally exhibit good filterability, so the above-mentioned filtration and washing operations can be performed relatively easily. worn,
Therefore, it is possible to obtain highly pure basic aluminum sulfate with good cleaning efficiency.

Furthermore, when performing operations such as the above-mentioned centrifugation or filtration, there is no need to raise the temperature of the reaction solution, and the operations can be carried out at room temperature. The basic aluminum sulfate spherical particles and aggregates thereof of the present invention are almost completely formed at the end of the addition of the soluble sulfate, and aging is generally carried out once after the addition of the soluble sulfate. A certain amount of time is sufficient. However, when the temperature of the suspension after the reaction is lowered, aggregates of spherical particles tend to form more easily. However, even if such aggregates occur, they can often be redispersed into spherical particles of 11 microns by treatment such as light crushing.

The basic aluminum sulfate spherical particles and aggregates thereof of the present invention can be used very effectively in the field of conventionally known basic aluminum sulfate or aluminum hydroxide.

That is, compared to conventionally known basic aluminum sulfate or aluminum hydroxide, the particle size is as small as ``submicrons''.
Moreover, since it is uniform, it has good dispersibility and can form a homogeneous composite when used to fill a resin or the like.

Furthermore, by firing the basic aluminum sulfate spherical particles and aggregates thereof of the present invention, aluminum oxide spherical particles and aggregates thereof can be obtained, which have excellent sinterability and are uniform spherical particles with submicron dimensions. Therefore, it is useful as a raw material for a sintered body or a filler for filling.

In particular, the basic iii#alj = rum of the present invention is generally easy to clean and can be obtained with high purity containing almost no alkaline content, so even when it is calcined to form aluminum oxide, it has very high purity. 1. Spherical aluminum oxide with such high purity and an average grain size of long bumicron is highly desired for the production of translucent alumina sintered bodies, phosphor crystal alumina, etc. The basic aluminum sulfate of the present invention is capable of meeting such needs.

The present invention will be described below with reference to Examples and Comparative Examples; however, the present invention is not limited thereto.

Example 1 N/2-AtC1, aqueous solution 400-
Add it and stir it with a magnetic stirrer.
To this was added 200 ml of N/2-NaOH aqueous solution at a rate of 1-7 minutes using a micro tube pump.

At this time, since it was a strong alkali, a heterogeneous reaction occurred in which the pH locally increased, and a small amount of gel-like precipitate was generated.

Therefore, after the addition of the N/2-Na OH aqueous solution was completed, stirring was continued for 12 hours. By doing this, a small amount of gel-like precipitate is redispersed, and theoretically, the general formula At(O
H) 1. A colorless and transparent basic aluminum chloride aqueous solution having a composition represented by so CAt, so was obtained. The pH of this solution was 5.86.

Similarly, the above reaction was carried out at a liquid temperature of 20°C.

600 d of the above basic aluminum chloride aqueous solution was placed in a jacketed flask and heated to 60C, and while stirring, 520 d of the N/4-Na2SO4 aqueous solution was added.
Using a micro tube pump, 2. Add O4 at a rate of 1 min.

About 1 hour after starting to add the N/4-Na2so4 aqueous solution, it started to become slightly cloudy, and after 1 hour and 20 minutes, it became cloudy and looked like kudzu soup. After 4 hours and 20 minutes, when the entire amount had been added, the mixture had become milky white, and when the stirring was stopped and the mixture was allowed to stand still, it sedimented and separated relatively quickly, separating into a white precipitate with low bulk and a supernatant.

When this milky white suspension was examined with an optical microscope, it was confirmed that numerous fine spherical particles with a diameter of about 0.2 μm were formed.

The temperature of the N/4-Na2804 aqueous solution was 20°C, but while it was being added, the temperature of the reaction solution was 58~58°C.
A friend kept at 60C.

After continuing to stir the suspension of spherical particles obtained by the above method for about 3 hours while maintaining the temperature at 60C, the heating was stopped and the liquid temperature was raised.

Leave to cool until it reaches about 30C. After the liquid temperature drops, A5
Suction filtration was performed using the filter paper of c, and the precipitate was separated by filtration.

At that time, the filterability was very poor, and the filter cake was dense and resembled potato starch.

The filter cake was then washed with approximately 500 ml of distilled water, the page was washed with ethanol, and finally the filter cake was washed with 24 dOc.
Drying was carried out for several hours to obtain a white dry cake of basic aluminum sulfate spherical particles. The dried cake was hard, easily crumbled, and roughly crumbled to a granular, smooth texture. The weight of the dry cake was 4.68f.

When the obtained white powder was examined using a scanning electron microscope, it was found that the diameters of the individual particles were approximately 0.2 #m and relatively uniform, suggesting that they were spherical or close to spherical in shape. It could be confirmed. It was also found that some of these spherical particles were aggregated like clusters of grapes.

J
It is shown in Figure 11.

Additionally, as a result of chemical analysis, the white powder contained AA k
22. the law of nature ! It was found that it contained 27.1N of Boa.

As a result, the composition of basic aluminum sulfate obtained in one example is given by the general formula At(OH)z, i'z(Son)
o, 54・1.21 It is thought that there is also O-1' represented by H2O.

The contents of iron, Na, ct, and other metal elements were all 100 ppm or less.

The yield was calculated to be 54% as recovery of kl.

The results of powder xi1 diffraction performed using CuKa m (40 kV, 120 JIIA) are shown in FIGS. 2 and 6. Figure 2 shows the wet foreshadowing obtained by simply washing the filter cake with distilled water, and Figure 6 shows the measurements taken for each sample after washing with ethanol and drying at 60°C for 12 hours. As seen in these figures, both diffraction patterns are 2
A peak is observed in the range of #=5 to 70°, 112
In the figure, near 2a=50°, in Fig. 5, FiZ#=2Ll
It only shows a slight low mainly around '.

Normally, the sample shown in Figure 3 is dispersed in water again to form powder X.
When line diffraction was carried out, an xIi11 diffraction pattern almost similar to that shown in FIG. 2 was obtained.

Further, FIG. 4 shows the results of DTA and TGt measurements of the sample dried at 60° C. for 24 hours after washing with ethanol. The heating rate was 10°C/min. The broad endothermic peak that appears up to around 600°C in this DTA line is due to the elimination of structural water and hydroxyl groups, and corresponds to a weight loss of about 55% of TG. Also.

DTA1111i around 10950℃ (Dfla)
H-y is due to the withdrawal of sulfate groups and corresponds to a weight loss of about 23% of TG. In fact, the exothermic peak around 1200°C is thought to be associated with the f-+tl phase transition.

The basic aluminum sulfate obtained in this example was
Powder X-ray diffraction was performed on samples fired at 0C and 12000C for 60 minutes, and it was found that the former had r-A42
In the latter case, a diffraction pattern power l of α-11205 was obtained. Furthermore, it was confirmed using a scanning electron microscope that the shape of the particles had hardly changed at that time.

Sample dried at 60C for 24 hours after washing with ethanol, 10
For samples baked at 00°C and 1200°C for 30 minutes, a rapid surface area measuring device 5A-
When the specific surface area was measured using 1000, it was found that 18
nl/l, 28#//f, 11dl? Met.

On the other hand, for the purpose of investigating the chemical properties of the basic aluminum sulfate obtained in this example, eta/-Jl/60°C after washing was conducted.
When an attempt was made to disperse a sample that had been dried for 24 hours in an aqueous N/4-NaOH solution, the sample became stuck and could not be dispersed even with ultrasonic axillary. When the sample in this state was examined using a scanning heavy electric microscope, it was found that the spherical particles had collapsed, which is probably why the sample had become gel-like. In addition to this gel, N/4-Nao
When an aqueous solution was added and left to stand, the precipitate dissolved and became transparent after about 1 hour.

Example 2 N/2-AACA, aqueous solution 400-
Add it and stir it with a magnetic stirrer.
To this was added 242 ml of N/2-KOH aqueous solution using a micro tube pump at a rate of 1-7 minutes.

After the addition of the N/2-KOH aqueous solution was completed, the solution was stirred for 12 hours to obtain a colorless and transparent homogeneous solution, and the pH at this time was 3.62.

In this way, basic aluminum chloride can theoretically be
It is believed that the composition is represented by the general formula At(OH)t,ao(41,2o).The above reaction was conducted at a liquid temperature of 30°C.

The above basic aluminum chloride aqueous solution 642°C was placed in a jacketed flask and heated to 70C, and while stirring, the solution was heated to 280°C. Aqueous solution 428-,
Additions were made using a microtube pump at a rate of 1.7-7 minutes.

A milky white suspension similar to that in Example 1 was obtained here as well, and when this was examined with an optical microscope, it was confirmed that spherical particles similar to those in Example 1 were produced.

The temperature of the N/4-2BOa aqueous solution was 30°C, but while it was being added, the temperature of the reaction solution was 1J67~
The temperature was maintained at 71°C.

The suspension of spherical particles obtained by the above method was filtered, washed and dried in the same manner as in Example 1 to obtain a white dry cake of basic aluminum sulfate spherical particles.
I got it. The dried cake quickly crumbled into a slurry powder.

As a result of chemical analysis, the white powder contained kt22.9.
%, ao4°26°2% was found to be included.

As a result, the composition of the basic aluminum sulfate obtained in this example is expressed by the general formula *A((H)z,xa(ao4)2
．． It is thought that there is also a note expressed as s6・1.11H20.

The yield was calculated to be 71% in terms of kA recovery.

Practical example 1 regarding this basic aluminum sulfate spherical particles
When the properties were examined using the same method as above, it was found that the diameter of the secondary particles was approximately within the range of 0.1 to 0.4 μm. In addition, the specific surface area of the sample dried with ethanol cleaning @SOC for 24 hours was 28 m'/f at 1000°C.
52W for a sample fired for 30 minutes? /l.

The sample fired at 1200C for 50 minutes had a value of 12 d/l. Other properties were almost the same as the basic aluminum sulfate spherical particles obtained in Example 1.

Example 3 N/2-AjCjs aqueous solution 400-
Add it and stir it with a magnetic stirrer.
To this, an aqueous N/2-NH4OH solution 267- can be added at a rate of 1-7 minutes using a micro tube pump.

After the addition of the N/2-・NH4OH aqueous solution was completed, the solution was stirred for an additional 12 hours, resulting in a colorless and transparent homogeneous solution, at which time the CpH
was 4.12.

The basic aluminum chloride obtained in this way is theoretically
General formula Aj(OH)2. It is thought that the composition is expressed by oocAt and ao. The above reaction was carried out at a liquid temperature of 25°C.

The above basic aluminum chloride aqueous solution 667- was put into a jacketed flask and heated to 70C, and while stirring, N/4-(NH4) 2804 aqueous solution 35
0- to 1.5 using a micro tube pump
Added at a rate of mg/min.

A milky-white suspension similar to that in Example 1 was obtained from the konin, and when this was examined with an optical microscope, it was confirmed that spherical particles similar to those in Example 1 were produced.

Same, the temperature of N/4- (NHa)280a aqueous solution is 25
During the addition, the reaction solution was heated at 1°C.
It was maintained at 1-168~71C.

The suspension of spherical particles obtained by the above method was filtered, washed and dried in the same manner as in Example 1 to obtain a white dry cake of basic aluminum sulfate spherical particles of 6.28 f.
I got it. The dried cake quickly crumbled into a powder of 500ml.

As a result of chemical analysis, the white powder contained Aj 23.5
^+ I found out that it contains 804 or 25.6%.

As a result, the composition of the basic aluminum sulfate obtained in this example has the general formula At(OH)2. s・(ao4)o
, st ・0.99 It is thought that there is also a note expressed in H2O.

The yield was calculated to be 82% as the recovery rate of Aj.

The properties of these basic aluminum sulfate spherical particles were further investigated using the same method as in Example 1. The diameter of the primary particles was 0.5μ6, and there were many secondary agglomerated particles after 4-rmQ. I found it to be 7.

Figure 5 shows an image of the ear taken with a scanning electron microscope at a magnification of 10,000 times.

The specific surface areas of the sample dried at 60C for 24 hours after washing with ethanol, and the sample baked at 100OC and 1200℃ for 60 minutes, respectively, were 1 art/l and 22! /l,
It was 8d/l.

Other properties were almost the same as the basic aluminum sulfate spherical particles obtained in Example 1.

Actual example 4 N/2-ktct5 aqueous solution 40 in a glass beaker
0- was added thereto and stirred with a magnetic stirrer, and 310 wIt of N/2-NHaOH aqueous solution was added thereto at a rate of 1-7 minutes using a micro tube pump.

After the addition was completed, the mixture was further stirred for about 12 hours, and the resulting solution was a colorless and transparent homogeneous solution with a pH of 14.45.

The basic aluminum chloride obtained in this way is theoretically
It is believed that the composition is expressed by the general formula kl(OH)2.52CLa,aa. Similarly, the above reaction was carried out at a liquid temperature of 250°C.

The above basic aluminum chloride aqueous solution 710- was put in a jacketed flask and heated to 70C, and while stirring, 240- of the N/4-N&2804 aqueous solution was added.
Addition was made using a microtube pump at a rate of 0.6 m/min.

A milky white suspension similar to that in Example 1 was obtained here as well, and when this was examined with an optical microscope, it was confirmed that spherical particles similar to those in Example 1 were produced.

The temperature of the N/4-Naz804 aqueous solution was 25C, but while it was added, the i1 degree of the reaction solution was 67 degrees.
The temperature was maintained at ~70°C.

The suspension of spherical particles obtained by the above method was filtered, washed and dried in the same manner as in Example 1 to obtain a white dry cake of basic aluminum sulfate spherical particles at 6.97 F.
I got it. The dried cake quickly crumbled into a powdery powder.

As a result of chemical analysis, the white powder contained 25.5 A4.
It was found that it contained 804% or 22.8%.

As a result, the composition of the basic aluminum sulfate obtained in this example has the general formula AA(OH)2.4i(804)0
．． 27-1.11 It is thought that it is represented by H2O.

The yield was calculated to be 91% as a recovery rate of AA.

Example 1 about this basic aluminum sulfate spherical particles
When the properties were examined by the same method as above, it was found that the diameter of the secondary particles ranged from 0.2 to 0.6 μm, and there were many secondary agglomerated particles of about 8 to 15 μm.

Further, the specific surface area of the sample dried for 24 hours at 4SOC after washing with ethanol, and the sample baked for 30 minutes at 100OC and 1200C, respectively, are 9w? i'f, 25! /l
, 8-/f.

Other properties were almost the same as those of the basic aluminum iI acid spherical particles obtained in Example 1.

Example 5 N/2-Az (No, ), aqueous solution 4 in a glass beaker
00- was added and stirred with a magnetic stirrer, and an N/2-NaOH aqueous solution 166- was added thereto at a rate of 1-7 minutes using a micro tube pump.

After the addition of the N/2-NaoH aqueous solution was completed, the solution that was stirred for 12 hours was a colorless and transparent homogeneous solution, and the pH at this time was
was 6.54.

Theoretically, the basic aluminum nitrate obtained in this way is
General formula Aj(OH)t, oo (NOx)z, o.

It is thought that the composition is as shown below.

The above reaction was carried out at a liquid temperature of 30C.

The above basic aluminum nitrate aqueous solution 555- was placed in a jacketed flask and heated to 60C, and while stirring, N/4-NazS heated to the same <60C was added.
Aqueous O4 solution 712- was added at a rate of 2.5 mg/min using a micro tube pump.

Here too, a milky white suspension similar to that in Example 1 was obtained, which was filtered, washed and dried in the same manner as in Example 1 to obtain a white dry cake of basic aluminum sulfate spherical particles at 2.25 F. I got it. The dried cake was crunchy and required pulverization.

As a result of chemical analysis, At was found to be 22°C in the dried cake.
．． It was found that it contained 9% and 27.5% of 804.

As a result, the composition of the basic aluminum sulfate obtained in this example has the general formula At(OH)2. x2(SO2)u
, si ・1.05H20.

The yield was calculated to be 28% as the recovery rate of A4.

The properties of the basic alkynium sulfate spherical particles were examined in the same manner as in Practical Example 1, and it was found that the diameter of the primary particles was 0.1 to 0.2 μm.

In addition, the specific surface areas of the sample dried at 60°C for 24 hours after washing with ethanol, and the samples baked at 1000°C and 1200C for 50 minutes, respectively, were 50 d/f, 52 d/f, and 1
It was 4td/l.

Other properties were almost the same as the basic aluminum sulfate spherical particles obtained in Actual Example 1.

Example 6 In Example 6, the addition rate of N/4-(NH4)2804 aqueous solution 350- was set to 1.0 mg/min, and the experimental operation was performed under exactly the same conditions other than that.

Here too, a milky white suspension similar to that of Example 1 was obtained.
This was filtered, washed and dried in the same manner as in Example 1 to obtain 6.25f of a white dry cake of basic aluminum sulfate spherical particles. Was the dried cake firm and firm?
By lightly crushing it, it became a fine powder.

As a result of chemical analysis, the white powder contained AA*'25.
4 N, Boa #26.511; I knew it was included.

As a result, the composition of the basic aluminum sulfate obtained in this example has the general formula AL(OH)LsaCBOa)o,
It is considered to be expressed as u ・0.99H20.

The yield was calculated to be 81% as recovery of kl.

The properties of the basic aluminum sulfate spherical particles were examined in the same manner as in Practical Example 1, and it was found that the diameters of the secondary particles were 0.1 to 0.2 μm and were well aligned.

In addition, the specific surface areas of the sample dried at 60C for 24 hours after washing with ethanol, and the samples baked at 1000C and 1200C for 30 minutes, respectively, were 21 d/f and 52 nl/
l, I Adl, t.

Other properties were almost the same as the basic aluminum sulfate spherical particles obtained in Actual Example 1.

Example 7 In Example 5, N/4-CNHa) 2804
The aqueous solution 350- was heated to 70° C., and the addition rate was 5.8 d1 min, but the experimental operation was performed under the same conditions except for that.

Here, too, a milky white suspension similar to that in Practical Example 1 was obtained, which was filtered, washed and dried in the same manner as in Practical Example 1, resulting in a white dry cake of basic aluminum sulfate spherical particles.
．． I got 98 f. The dried cake quickly crumbled into a sticky powder.

As a result of chemical analysis, the white powder contained Aj of 23.9.
It was found that it contained 804% or 22.5%.

As a result, the composition of the basic aluminum sulfate obtained in this example has the general formula Aj(OHh, 4s(804)0.
24 ・1-'04 It is thought to be expressed as H2O. The recovery rate of At was calculated to be 79%.

The properties of the basic aluminum sulfate spherical particles were examined in the same manner as in Example 1, and the diameter of the secondary particles was found to be 0.4 to 0.8 μm.

In addition, the specific surface areas of the sample dried at 60°C for 24 hours after washing with ethanol, and the samples baked at 1000C and 1200C for 30 minutes, respectively, are 5d/f, 18nl/f,
It was 6d/f.

Other properties were almost the same as the basic aluminum sulfate spherical particles obtained in Example 1.

” Example 8 In Example 1, the temperature of the basic aluminum chloride aqueous solution when adding the N/4-Na2804 aqueous solution was 50C.
The experiment was carried out under the same conditions except for the following conditions.

That's 4 naked eyes! J! A milky white S suspension similar to Example 1 was obtained. When this suspension was examined with an optical microscope, it was found that it had spherical particles with a diameter of about 0.1 to 0.2 μm and a length of 10 μm * **Fibrous particles were generated.

In addition, when observation was performed using a scanning lid electronic microscope in the same manner as in Example 1, the width was 0.2 μm and the length was 10 μm.
It was confirmed that fibrous particles after IIi and spherical particles with a diameter of 0.2 μm were mixed together.

Example 9 In Example 5, the temperature of the basic aluminum chloride aqueous solution was maintained at 80° C. when adding the N/4-Na 280 a aqueous solution, and the experimental operation was performed under exactly the same conditions other than that.

In this case as well, a milky white suspension was obtained that was visually similar to that in Example 1. When this suspension was tried to be filtered and washed in the same manner as in Example 1, the filterability was extremely poor. I realized that.

After passing through and washing, the dried cake obtained by drying in the same manner as in Example 1 was sticky and had a slightly translucent feel.

The dried cake was observed using a scanning type electron microscope in the same manner as in Example 1, and was found to be 110.
It was found that an amorphous gel was formed along with spherical particles of 1 to 0.2 μm.

Comparative Example 1 In Example 3, the temperature of the basic aluminum chloride aqueous solution when adding the '/4-Na2804 aqueous solution was
The experiment was carried out under the same conditions except that the temperature was maintained at ℃.

Visually, a milky white suspension was obtained which was similar to that in Example 1. When this suspension was examined under an optical microscope, the average width was 6 μm.

It was found that countless prismatic particles with a length of about 20 μm were produced, and that no spherical particles as seen in the examples were produced.

This suspension of prismatic particles was further stirred for about 12 hours, and then filtered, washed and dried in the same manner as described in Example 1 to obtain 5.62 f of smooth white powder.

As a result of chemical analysis, the white powder contained AA or °24.
6 N, 5Oait'21.6N included Te1. -m
I knew it was Ruco.

As a result, it is thought that the composition of the nonagonal columnar basic aluminum sulfate obtained in this comparative example is expressed by the general formula %.

The specific surface area of the sample dried at 40°C for 24 hours after washing with ethanol for 17'h, and the sample baked at 1000C and 1200C for 30 minutes, respectively.
l, 25w? /l.

Comparative Example 2 In Example 1, the temperature of the basic aluminum chloride aqueous solution when adding the N/4-Na2804 aqueous solution was changed to 20°C.
The experiment was carried out under the same conditions except for the following conditions.

In this case, a milky-white suspension was obtained that was visually similar to that in Example 1. However, when this suspension was examined with an optical microscope, it was found that there were countless fibrous particles with an average length of about 50 μm. It was found that spherical particles such as those observed in Examples were not produced at all.

This suspension of fibrous particles was filtered, washed and dried in the same manner as described in Example 1 to form a white sheet.5.
I got 57 f.

When the obtained white sheet was examined using a scanning electron microscope, it was confirmed that the fibrous particles overlapped, forming a part similar to a non-woven fabric. The size of the fibrous particles was approximately within the range of width α1 to 0.5 μm and length 40 to 70 μm.

Further, as a result of chemical analysis, it was found that 24.2% of AA and 25.4Xt of S04 were contained in the sheet-like dry cake.

As a result, the composition of the basic aluminum sulfate obtained in Comparative Example 1 was determined by the general formula kl(OH)2. a.

(804)0. It is considered to be expressed as SO・0.85I (20S).

The yield was calculated to be 488 as the recovery rate of At.

In addition, the specific surface areas of the sample dried at 60°C for 24 hours after washing with ethanol, and the samples baked at 1000C and 1200C for 50 minutes, respectively, were 21 d/f and 70 vd/f.
l, 19d/l and nine.

Comparative Example 6 In Example 3, the temperature of the basic aluminum chloride aqueous solution when adding the N/4-Na2SO4 aqueous solution was set to 95°C.
The experiment was carried out under the same conditions except for the following conditions.

However, by the time the N/4-NIL2804 aqueous solution had been added, it had become gel-like, and when examined under an optical microscope, it was found that no spherical particles as seen in the Examples had been formed.

Comparative Example 4 N/2-htct, aqueous solution 400-
Add it and stir it with a magnetic stirrer.
To this was added 60ml of N/2-NH4OH water solution at a rate of 1-77 minutes using a micro tube pump.

After the addition was completed, the mixture was stirred for about 12 hours, and a colorless and transparent homogeneous solution was obtained, with a pH of 6.66.

The basic aluminum chloride obtained in this way is theoretically
It is thought that the composition is represented by the general formula At(OH)o,4sctz,ss.

The above operation was carried out at a liquid temperature of 25°C.

The above salt A aqueous solution of aluminum chloride (460) was placed in a jacketed flask and heated to 60°C, and while stirring, 900 - of the N/4-Na 2804 aqueous solution was added using a micro tube pump. Even after the total amount of force f was added at a rate of 5.4 d1 min, no precipitate was observed to form.

Therefore, when an aqueous solution of N/4-NIL2804 was further added, there was no change, and basic aluminum sulfate spherical particles as shown in Examples could not be obtained.

The temperature of the N/4-Naz804 aqueous solution was 25C, and while it was being added, the temperature of the reaction solution was 57~57C.
It was kept at 60°C.

[Brief explanation of the drawing]

FIG. 1 is a scanning electron micrograph (magnification: 100) of basic aluminum sulfate spherical particles obtained in Example 1 of the present invention.
00 times). FIG. 2 and FIG. 6 are powder X-ray diffraction patterns of the basic aluminum sulfate spherical particles obtained in Example 1 of the present invention in wet and dry states, respectively. FIG. 4 shows the D'I'A and TG curves of the basic aluminum sulfate spherical particles obtained in Example 1 of the present invention. FIG. 5 is a scanning electron micrograph (magnification: 10) of basic aluminum sulfate spherical particles obtained in Example 3 of the present invention.
000 times). Patent Applicant: Tokuyama Soda Co., Ltd. J69 Procedural Amendment Written March 23, 1982 %#IFrr Blind Haruki Shimada L, Incident Indication 1981 Patent Application No. 19811 2, Name of Invention Spherical Basicity Aluminum sulfate and its manufacturing method 3, relationship with the amended case Patent applicant postal code 745 Address 1-1 Mikage-cho, Tokuyama-shi, Yamaguchi Name (3)
18) To Taizan 1-gai Co., Ltd., contact information: Tokyo Port Section New 111-4-s Tokuyama-Tatsu Co., Ltd. Tokyo Headquarters Patent Information Department - 6, Contents of the amendment in the "Detailed Description of the Invention" of the Specification ( Correct "RS liquid" on page 15, line 8 of the specification to "liquid temperature." (2) Correct "solution" on line 3 of page 16 of the same 1m to "salt solution."
Correct to. (3) Correct "infinite number of particles" on line Tl of page 42 to "infinite number of particles". that's all

Claims (1)

[Claims]) General formula AA(OH)11(804)b-nH20(
However, a+)b=3 +2.30<a≦2.50.0.
25≦b≦0.35°O≦n≦10) Basic aluminum sulfate spherical particles and aggregates thereof. (2) General formula At(OH). Xa (However, XFi-
Indicates the value of butyric ion, c-14=3, 0.5≦C≦2
．． 55), while maintaining the temperature of the basic aluminum salt solution represented by the general formula Al(O
H)a(Boa)b -nH20CHowever, a+2b
=3, 2.50≦a≦2.50. 0.25≦b≦0.35, 0≦n≦10) A method for producing basic aluminum sulfate spherical particles and aggregates thereof. (6) Soluble sulfate salt in a solution with a molar ratio of 804/At (3-c)/2 (however, the sign in the general formula At(OH)cXa of cij basic aluminum salt)
The addition time T (unit: 2 hours) until the value of is 0.5
The manufacturing method according to claim 2, wherein the addition is performed at an addition rate that satisfies ≦T≦12. (4) When a basic aluminum salt solution is added to a -valent anion aluminum salt solution, an alkaline solution is added to the OH in the solution.
The manufacturing method according to claim 2, which is obtained by adding an amount such that the molar ratio of /Aj is in the range of 0.5 to 2.55.