JPS58156527A - Preparation of amorphous aluminosilicate - Google Patents

Abstract

PURPOSE:To develop an amorphous aluminosilicate having a high oil absorption and improved ion exchange ability, by reacting a solution of an alkali metallic aluminate with a solution of an alkali metallic silicate under specific conditions. CONSTITUTION:An aqueous solution of an alkali metallic aluminate having 0.15-1.0(Al2O3/M2O) molar ratio (M is an alkali metal, e.g. Na, K or Li) and 1-15wt% Al2O3 concentration and a solution of an alkali metallic silicate having 1-4(SiO2/M2O) molar ratio and 5-20wt% SiO2 concentration are added to water to give 2.0-4.5wt% M2O concentration. The resultant reaction mixture is then reacted at 60 deg.C or above. Alternatively, the solutions are mixed to give <= 2.5wt% M2O concentration, and the resultant mixture is reacted to give an amorphous aluminosilicate having >=200ml/100g oil absorption and the cation exchange capacity equal to or higher than that of various kinds of zeolite.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing amorphous aluminosilicate,
In particular, the present invention relates to a new method for producing amorphous aluminosilicate, which has the physical and chemical properties of amorphous silica and zeolite, which is generally referred to as white carbon.

Currently, amorphous silica such as anhydrous silicic acid and hydrous silicic acid has high oil absorption properties due to their high structure.

Since it has a large specific surface area, many uses have been developed using this property, including fillers for rubber, sizing agents for paper manufacturing, agricultural chemicals, and paints. However, this type of amorphous silica has no ion exchange ability, for example.

When this is used as an anti-settling agent or viscosity modifier for an emulsion for agricultural chemicals, it is not preferable to dilute it with water at the time of use because the emulsion stability decreases. on the other hand.

Crystalline aluminosilicate, called zeolite,
It has high ion exchange properties and is currently widely used in areas such as builders for synthetic detergents, catalysts and adhesives, etc., but its oil absorption is at most 60, I#'100P, and has high oil absorption. It cannot be used for the required purpose.

In addition, recently, amorphous sodium aluminosilicate fine powder, which is commercially available under trade names such as ZeOlex J, has been applied in the same field as amorphous silica.
The oil absorption amount is about 120 to 150 d'1OOf, and the ion exchange ability is also low.

The present invention aims, in particular, to provide a novel amorphous aluminosilicate having unprecedented high oil absorption and large ion exchange capacity.

The object of the present invention is to provide a method for producing an amorphous aluminosilicate having an oil absorption of 200 m/100 F or more and a cation exchange capacity comparable to that of various zeolites.

Amorphous aluminosilicates have the general formula M, O,; AZ, 0
゜2.5-5.28i0. , xH,O (where 1M represents an alkali metal), and various methods for producing this amorphous aluminosilicate have been studied in the past.

For example, the method described in JP-A-52-58099 is
in aqueous solutions of alkali metal silicates.

Oil absorption i.
t 75 altl 00f or more, Ca replacement lid 200
A method for producing an amorphous aluminosilicate having physical properties of mycacO*/f or higher is disclosed. However, in a method such as this method in which an aqueous solution of an alkali metal aluminate is added to an aqueous solution of an alkali metal silicate,
High oil absorption, ie.

Amorphous aluminosilicate having physical properties of 20 D y/100j' or more cannot be produced. Also, JP-A-55-1
The method described in Publication No. 62418 is a method for producing an amorphous aluminosilicate having a relatively large particle size and excellent ion exchange ability by continuously supplying an aqueous aluminate solution and an aqueous alkali silicate solution to a reaction system. Disclosed. According to this method, an amorphous aluminosilicate with a large particle size and easy to filter and wash can be obtained, but the total M and O of the reaction system are 0.
Due to the high concentration, it is difficult to obtain an amorphous aluminosilicate with high oil absorption, which is one of the objects of the present invention.

As described above, the present inventors aimed to produce an amorphous aluminosilicate having high oil absorption and ion exchange properties comparable to zeolite.

As a result of various studies, we obtained the desired amorphous aluminosilicate by reacting an alkali metal aluminate solution and an alkali metal silicate under certain specific conditions as described below. The present invention has been completed based on two findings.

In other words, the first invention is based on the M and O concentrations in one reaction system (however, 1M
indicates an alkali metal. ) is 2.0 to 4.5% by weight, VA Si, In the second invention, the alkali metal silicate solution is added to the alkali metal aluminate solution so that the M, 0 concentration (1M indicates an alkali metal) in one reaction system is 2.5% by weight or less. The present invention relates to a method for producing an amorphous aluminosilicate comprising:

Regarding the raw materials used in the present invention, they are an alkali metal aluminate solution and an alkali metal silicate solution, and in the present invention, alkali metals are those belonging to Group 1a of the periodic table, such as sodium, potassium, and lithium. Regarding the former, examples include sodium aluminate, potassium aluminate, and sodium aluminate, while regarding the latter, examples include sodium silicate, potassium silicate, and lithium silicate. These can be adjusted to appropriate molar ratios and concentrations using caustic alkali and water as needed.

In carrying out the method of the invention of Ratio 1, it is first necessary to prepare an alkali metal aluminate solution and an alkali metal silicate solution.

Regarding the former, A1 mouth O3/M, O molar ratio 0.15
~1.0, preferably U, in the range of 15 to 0.63 from the viewpoint of stability of the solution, and regarding its concentration.

An Al5Os concentration of 1 to 15% by weight, preferably 3 to 10% by weight, is desirable from the viewpoint of manufacturing and physical properties. For the latter citrate alkali gold M salt solution, EliO.

7M, 0 molar ratio of 1 to 4 can be used.

As for its concentration, it is possible to use Sin with a concentration of 5 to 20% by weight.

By the way, it is necessary to gradually add both of the above solutions to water at the same time. An amorphous aluminosilicate with high oil absorption cannot be produced simply by simultaneously adding an alkali metal aluminate solution and an alkali metal silicate solution as raw materials. The reason for this is not clear, but 1. When both solutions are added to water as in the present invention, 1.
When the total M and O concentrations in the reaction system are 1% or less, gelation occurs, a highly viscous polymer is produced, and as one reaction progresses, M and O gradually increase.
It is believed that the higher the concentration, the more the polymer is fragmented and the more oil-absorbing product is produced. On the other hand, when both solutions are added without introducing water in advance, the M of the reaction system increases from the beginning.
9, the Q concentration is high and the polymer production mechanism is different from that of the present invention.
It is believed that a product such as that of the present invention cannot be obtained.

' Regarding reaction mixture, 60"c or less is preferable.

If the temperature exceeds 60°C, the physical properties of the product, especially the oil absorption, tend to decrease. In addition, during the reaction 2, it is necessary to perform strong stirring, and in particular, 1, when the reaction proceeds according to the present invention, the reaction liquid becomes highly viscous from a certain point, but from this point until the end of the simultaneous addition. Vigorous stirring is advisable. The addition time for both solutions is desirably 15 to 60 minutes for ripening after addition of both solutions.

It may be carried out at a temperature of 60° C. or lower for at least 5 minutes, preferably for 15 to 60 minutes.

Therefore, both of the above solutions are S l o, /A l of one reaction system.
a Os molar ratio is 1.0 to 4.0. Preferably 1.5
It is necessary to add it to the water at the same time so that it becomes 0 to 3.0. If the above range is exceeded, the oil absorbing cap and cations (Ca,
My) Exchange capacity decreases. Particularly important in the first aspect of the present invention is the concentration of M and O in the reaction system at the end of one reaction, that is, the amorphous aluminosilicate produced with the alkali metal ions in one reaction solution. The total amount of alkali metal ions is 2.0 to 4.5 times the total amount of reaction contents i96. Preferably, the amount of water is varied in advance according to the concentration of both solutions, which are raw materials, in the 9 reaction tanks so that the concentration is 2.25 to 4.0% by weight, and the first reaction is completed. be.

If it falls below the above range, a gel-like substance will form and it will not be possible to obtain a highly oil-absorbing substance, and if it exceeds the upper limit, the oil absorption will be 200 T.
It is not possible to obtain an amorphous aluminosilicate having R1/1009 or more and a high cation exchange capacity.

The effects of the first invention will now be illustrated with specific examples as follows.

Hereinafter, 96 indicates weight %.

Specific example 1゜Contents: Water IKI+ was charged into a reaction tank of 61 cm, and sodium silicate solution (810□6.0
0%, Na, 01.97%, SiO,/Na,
0 Mo/L/ratio 3.15) 500f and the sodium aluminate solution shown in Table 1 (A1.Os 5.05%) 5
00y was added to the water while stirring in a homomixer for simultaneous E 2 CI minutes. 2 at 40'C after addition
The cake was aged for 0 minutes, then filtered and washed, and the resulting wet cake was left to dry at 105° C. until it reached a constant weight. The results are shown in Table 1.

Table 1 ◆ indicates a comparative example.

1) How to measure loss on ignition...Put a dried platinum crucible into 8
Baked at 00'C for 1 hour, left to cool in a desiccator, and weighed (BW). Samples 1 to 6y are placed in a platinum crucible and weighed (BS). Next, the platinum crucible containing the sample was ignited at 800° C. for 1 hour, allowed to cool in a desiccator, and its weight was weighed (SW).

The ignition loss (g) was determined from the following formula.

2) Method for measuring oil absorption: Weigh sample 1F.

Place on a glass plate and sprinkle linseed oil on it.

- Add the linseed oil little by little using a lettuce, mix well with a stainless steel spatula, and determine the amount of linseed oil added when the sample becomes a lump.

In addition, the oil absorbing lid is converted into the unit amount required for 100y of sample, and its -
Display in numbers.

6) Measuring method of Ca exchange capacity...Into a 10011e Erlenmeyer flask, add calcium chloride solution (121,70 (1 myy)
Take CaCOx/l) 2CJyd, add 1.0 Of sample as anhydride (calculated from loss on ignition),
The mixture was shaken and stirred at 25°C for 15 minutes.
20% when the M and O concentrations in the reaction system are within the range of 2.0 to 4.5%.
A product with an oil absorption of 0 mt'/100 P or more was obtained, and the Ca exchange capacity was also 200 mycaco,/
Around p can be obtained. Regarding the Ca exchange capacity, the values in Table 1 are the values when drying to a constant weight at 105'c using a static drying method. The Ca exchange capacity is the highest when the moisture content is 1 t84.0%], and the Ca exchange capacity is the highest when the moisture content is 25%.
my CaC0, Luca with physical properties of 71 or higher, 25%
Below that, the physical properties tend to decrease.
During drying, it is necessary to avoid prolonged exposure to high temperatures, and when a higher Ca exchange capacity is desired, freeze drying or spray drying methods are preferred.

By the way, the fine powder that precipitated after the 9 reaction and aging is as follows.

It is separated from the mother liquor by centrifugation, and if necessary, the mother liquor can be concentrated and recycled for reuse.

Therefore, when the amount of metal group 0 in one reaction system is within the range of 2.0 to 4.5%, the amounts of M and O incorporated into the product are as follows.

It is constant at 1 to 1.2 mol per 1 mol of Al stock Os of the charged raw material, and the amounts of Na and O in the mother liquor are linearly within the concentration range of 1.5 to 5.996 within the above range.

The separated fine powder was then washed with water to remove free alkali metal salts, then dried and ground.

A product with the desired particle size can be obtained.

Regarding drying methods, static drying and spray drying are used.

This can be done by various methods such as freeze drying. However, as mentioned above, the Ca exchange capacity changes depending on the degree of dryness, so care must be taken. Depending on the application, it can also be used without drying.

Next, to describe the second invention, the present invention is an amorphous material having physical properties of high oil absorption and high cation exchange capacity by adding an alkali metal silicate solution to a dilute alkali metal aluminate solution. This is a method for producing aluminosilicate.

Regarding the alkali metal aluminate solution used in the second invention, the molar ratio of Al*051M and O is 0.15-1.
0, preferably in the range of 0.15 to 0.66 from the viewpoint of solution stability, and its concentration.

In view of physical properties, M and O concentrations are preferably 2.5% or less, preferably 2.096% or less. For such concentration and composition adjustment, water is introduced into one reaction tank in advance.

This can be carried out by adding a highly concentrated alkali metal aluminate solution and caustic alkali to this. or,
An alkali metal aluminate salt solution prepared in advance as described above may be used. On the other hand, regarding the alkali metal silicate solution, SiO,'/M80 molar ratio 1
~4 can be used, and regarding its concentration,
Although not particularly limited, 1 usually s10. A material having a concentration of 20% or less can be used.

The gist of the second invention is that the M and O concentrations in one reaction system are −2,
The purpose is to add the alkali metal silicate solution to the alkali metal aluminate solution so that the amount is 5% by weight or less.

By the way, as described in the reference example below, M of the 9 reaction system,
The method of adding an alkali metal aluminate solution to an alkali metal silicate solution so that the zero concentration is 2.596 or less does not increase the oil absorption of the product.

The effects of the second invention will now be illustrated with specific examples as follows.

Specific Example 2 In a reaction tank with an internal capacity of 61, 1.7501 of the sodium aluminate solution shown in Table 2 was charged, and at a reaction temperature of 40°C, 1 g of the sodium silicate solution 250 f shown in Table 2 was heated in a homomixer for 8 minutes. The mixture was added without stirring. After the addition was completed, the mixture was aged at 40° C. for 60 minutes, followed by filtration and washing, and the resulting wet cake was left to dry at 105° C. until it reached a constant weight. The results are shown in Table 2.

! The stamp indicates a comparative example.

As is clear from Table 2, the concentration of 40 in one reaction system is 2.5
% or less, with high oil absorption.

Moreover, an amorphous aluminosilicate having a high Ca exchange capacity can be obtained. In addition, the M, 0 concentration of the above reaction system is 2.5%.
Under the following conditions, the lower the molar ratio of 8108/AjsOs in one reaction system, the more highly oil-absorbing amorphous aluminosilicate can be obtained.

Filtration, washing, drying, pulverization, etc. after the reaction may be carried out in accordance with the first invention.

The amorphous aluminosilicate obtained by the present invention has high oil absorption and a high cation response rate, so it can be used for medicinal purposes, paint, paper, toothpaste and detergent gas, and aromatic. It can be used as an adsorbent for substances.

Hereinafter, nine examples of the present invention will be further explained.

Example 1゜1.5㎜ of water was charged into a reaction tank with an internal capacity of 61゜ and the reaction temperature was 6㎜.
At 8°C, add sodium silicate solution (Sin.

12.00%, Na1O! 1.94%, 8i0. /
Halo % k ratio 5.15) 500p and sodium aluminate solution (A4*Oa 10.10%, Na,
012, 60%r A/, 0.7Na, 0 molar ratio 0.
49) 500y was simultaneously added to water for 20 minutes while stirring with a homomixer. (Reaction system) Ha, 03.3
1%). After the addition was completed, the mixture was aged at 40'C for 25 minutes and then filtered to separate the mother liquor.

The wet cake was then repulped for 15 minutes.

Wet cake 595.2g! I got it. The obtained wet cake was left to dry at 105"C and ground to x#j amorphous sodium aluminosilicate fine powder (loss on ignition: 16.
75%, Ha, 018.95%, Am 0.26.51
%, 810m 40.02 '16) 140y
I got it. This fine powder has an oil absorption capacity of 215m1QLI W
, has physical properties of an Oh exchange capacity [184 my CaC0a /9 and an average particle size of 8.7 μm.

In addition, the same wet cake freeze-dried has an oil absorption of 225
dl 100 P, Ca exchange capacity 260 my
It had physical properties of CaC0°/y and an average particle diameter of 8.2μ.

Example 2゜Pour 1 portion of water into a reaction tank with an internal capacity of 31°C and bring the reaction temperature to 57°C.
'c, sodium silicate solution (sio).

6.00%, Na, 01.97%, SiO,/
Na, O molar ratio 6.15 to 500F and sodium aluminate solution (Am OI 6.80%, Na, 011.2
7. Aj! mow/Nam0 molar ratio 0.57) 500
and y were simultaneously added to water for 20 minutes while stirring with a homomixer. (Na in the reaction system, 03.31515) After the addition was completed, the mixture was aged at 67'C for 25 minutes.

The mother liquor is then separated by filtration and the wet cake is then filtered for 15 minutes.
After repulping for minutes, a wet cake of 339.42 was obtained.

The obtained wet cake was left to dry at 105'C and ground to give amorphous sodium aluminosilicate fine powder (loss on ignition 18.95%, Na, 018,25% - Al10a
25.0196, Si0.38.09 76.
I got 6 y. This fine pulverization has an oil absorption of 200 m/1
00y.

Ca exchange capacity 2 self 6 It has physical properties of 4.6μ.

Example 6.

Pour 1 portion of water into a reaction tank with a capacity of 61 kg, and the temperature of the 1 reaction source is 30°C.
, potassium silicate solution (6.00% to 8i, K, 0
5.08%, 5iOs/@O molar ratio 5.06)5
00 and sodium aluminate solution (A40i s.o.
s%.

Na1Oi i. 27= AmO, /Na,O −E
k ratio 0.27) and 50[]r were simultaneously added to water for 25 minutes while stirring with a homomixer. (M, o of reaction system 3.59%) After completion of addition. The mother liquor was aged at 65"C for 20 minutes and then filtered to separate the mother liquor. The wet cake was then repulped for 15 minutes to obtain a wet cake 29B.6y. The wet cake was left to dry at 105°C and ground. Amorphous sodium potassium aluminosilicate fine powder (ignition loss 17.53%, Na, O l 4.15%, current 0
4.06%. AI! 5oi2a. 87%, 810,
40.79%) 63.41 was obtained. This fine pulverization absorbs oil! [255IIIe/100y, Ca exchange capacity 2 (
It has physical properties of 17 mg (:aCQ/i 00jF and an average particle size of 6.4μ).

Example 4.

Sodium aluminate solution (A
Itos 1.44 96, Na,O 1.7 9
96-Al5OINa-0 molar ratio 0.49) 17
Sodium silicate solution (S'Os 1 2.0 G 96, NaNO
2,94 96,8iO,/Na,O molar ratio 3.1
5) 250f was added for 10 minutes while stirring with a homomixer.

(Reaction system) Ha, 0 2, Q 6%) After completion of addition, 65
At ℃! The mixture was aged for 15 minutes and then filtered through V to separate the mother liquor.

The wet cake was then repulped for 15 minutes.

A wet cake 3 1 5.3 f was obtained. The resulting wet cake was left to dry at 105'C. Pulverized into amorphous sodium aluminosilicate fine powder (ignition loss: 21, 87%.
Na. 0 16.85%. Ai*0s26. '20
N. Sin.

39,62%) 72.1y was obtained. This fine powder has an oil absorption of 205 me/100f and a Ca exchange capacity of 222.
It has physical properties of mpCaCOJ and average particle size of 6.0μ.

Reference example content! Sodium silicate solution (B10
r3. Ll 0 96. Na, O O. 99%,
8i0,/Na,O molar ratio 3,15) 100Dp was prepared and a sodium aluminate solution (A
Itos2.53$. Nam.

z. 15s. AJ+Oi/NagO%/L. Ratio 0.
49J1000y was added for 20 minutes while stirring with a homomixer. (2.07% of Na,0 in the reaction system) After completion of addition.

Aged at 40'C for 25 minutes, then filtered to separate the mother liquor. The wet cake was then repulped for 15 minutes. A wet cake of 417.5 y was obtained. The obtained wet cake was left to dry at 105°C. Grind into amorphous sodium aluminosilicate fine powder (ignition loss 15.95%, N
a,0 16.65%, A/,0.

24.06%. 810143.50%) 65.0y was obtained.

This fine powder has an oil absorption capacity of 130 vol/100 g! ．．
Ca exchange capacity! It has physical properties of 175 mP C&COs/f and an average particle size of 4.6μ.

Claims (1)

[Claims] 1. An alkali metal aluminate solution and an alkali metal silicate so that the M and O concentrations in the reaction system (0M indicates an alkali metal) are 2.0 to 465% by weight. A method for producing an amorphous aluminosilicate comprising adding a solution to water. 2. An amorphous solution made by adding an alkali metal silicate solution to an alkali metal aluminate solution so that the concentration of circle 0 (2M indicates an alkali metal) in the reaction system is 2.5% by weight or less. Method for producing aluminosilicate.