JPS6246492B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing crystalline aluminosilicates. More specifically, the present invention relates to a method for producing a concentrated slurry of crystalline aluminosilicate having excellent performance as a detergent builder.

Cleaning agents based on anionic surfactants such as soap, LAS, and AOS create poorly soluble salts with divalent metal cations contained in hard water, resulting in problems such as reduced cleaning power and scale formation. known to cause In order to prevent this and enhance the cleaning effect, various phosphates are used as so-called builder components. This phosphate has the ability to chelate and sequester divalent cations, but on the other hand, as a source of eutrophication to environmental waters, its use is becoming limited, especially in sealed waters.

Therefore, methods using various chelating agents and aluminosilicate as substitutes for the function of phosphates were proposed and disclosed (for example, in JP-A No.
(See Publication No. 12381, etc.) As for aluminosilicate, its cation exchange ability has been well known for a long time, and its synthesis method is also known, for example, as seen in Japanese Patent No. 237383. Further, its use as a cleaning agent is also disclosed in Japanese Patent Publication No. 1119/1983 and is basically known.

However, the methods proposed so far do not consider the aluminosilicate manufacturing process and the detergent manufacturing process in an integrated manner, so they are by no means satisfactory from the perspective of manufacturing aluminosilicate-containing powder detergents. It's hard to say. In some cases the processes have been redundant and redundant, and in others the performance properties of the final detergent have been very poor.

Therefore, the present inventors conducted extensive research in order to develop an ideal process from the viewpoint of producing a powder cleaning agent.

The ultimate simplified aluminosilicate manufacturing process that can be directly linked to the powder cleaning agent manufacturing process is to add an alumina source and a silica source to the cleaning agent slurry base, and then add the ion-exchangeable aluminosilicate therein. However, this has several drawbacks. One is that the added alumina source creates the anionic activator and salt of the detergent. In addition, aluminosilicate gel, which is simply a mixture of alumina source and silica source at normal temperature, does not have ion exchange ability, so heating is required for crystallization, but heating of a system diluted with a detergent slurry base is - Cooling is not only inefficient, but also the heating and cooling behavior of such a multicomponent system is extremely complex from a phase diagram perspective, making it difficult to control. Furthermore, during heating, the coexistence of inorganic salts such as mirabilite and soda ash in the detergent slurry base may significantly inhibit the development of ion exchange properties. As described above, the above method is not efficient from a technical and economic point of view.

Next, the ideal solution would be to mix the alumina source and silica source to create an aluminosilicate gel, and add this to the powder slurry base at the same time as it crystallizes.
The first thing to do is to dry them.

In order to carry out this method, an extremely highly concentrated aluminosilicate slurry is required, but this is a method for producing an aluminosilicate slurry that is highly concentrated, has excellent builder performance, and has excellent powder physical properties when made into a powder detergent. was previously unknown. Therefore, the present inventors conducted extensive research to find a method for producing aluminosilicate that satisfies the above conditions, and finally arrived at the present invention.

That is, in the present invention, a 30 to 70% by weight sodium aluminate aqueous solution is used so that the composition of the mixed solution has a molar ratio of 1.5 to 2.0 Na ₂ O: 1 Al ₂ O ₃ : 2.0 to 2.5 SiO ₂ : 15 to 30 H ₂ O. A method for producing a crystalline aluminosilicate slurry for detergent formulation, which comprises mixing and gelling a 35 to 50% by weight aqueous sodium silicate solution and crystallizing at 70 to 110°C.

In the production method of the present invention, it is particularly important that the concentrations of the sodium aluminate aqueous solution and the sodium silicate aqueous solution be within the above-mentioned ranges, and that the composition of the two-liquid mixed solution be within the above-mentioned molar ratio range. It is.

If the concentration of the aqueous solution is too small, the concentration of the slurry produced will be too small and the object of the present invention will not be achieved, and if it is too large, the crystal particles of the aluminosilicate slurry produced will become coarse, and the concentration of the slurry produced will become too large. The physical properties of the powder deteriorate. Furthermore, if the sodium silicate aqueous solution exceeds 50% by weight, homogeneous mixing is impossible.

Regarding the composition of the mixed solution, the amount of Na ₂ O
When the amount is less than 1.5 times the amount of Al ₂ O ₃ by mole, the crystallization of the aluminosilicate is delayed, and when it is more than 2.0 times the amount of Al 2 O 3 by mole, the powder physical properties of the detergent are reduced and the washability is also reduced. Furthermore, if the amount of SiO ₂ is less than 2.0 times the mole of Al ₂ O ₃ , the aqueous aluminum salt will remain in the aluminosilicate and interact with the surfactant, which is a component of the cleaning agent, which is undesirable. It is undesirable because it reacts with sodium silicate, which is a builder, and forms an insoluble gel that adheres to clothes during washing. Furthermore, if the amount of SiO ₂ is more than 2.5 times the amount of Al ₂ O ₃ by mole, the performance of the produced aluminosilicate as a builder decreases.

The aqueous sodium aluminate solution used in the present invention can be obtained by dissolving sodium aluminate in water, dissolving aluminum hydroxide in a sodium hydroxide solution, or the like. In particular, the method of dissolving aluminum hydroxide in an aqueous sodium hydroxide solution can yield an extremely highly concentrated, especially supersaturated, aqueous sodium aluminate solution, so it is preferable to use the solution obtained by this method as the starting solution. . When a supersaturated aqueous solution is used, fine crystals may precipitate in some cases, but this does not pose any particular problem in carrying out the present invention.

As the sodium silicate used in the present invention, those having various Si/Na ratios can be used. Therefore, any of the commercially available silica No. 1, No. 2 silica, and No. 3 diatom can be used as is. However, considering the overall molar ratio, No. 2 or No. 3 silica is superior.

In carrying out the present invention, it is necessary to thoroughly mix the two reaction liquids. For this purpose, it is preferable to use a powerful stirring mixer such as a line mill, gear pump, turbine pump, Ledge mixer, or the like.

In the reaction, it is preferable to gradually add an aqueous sodium aluminate solution to a sodium silicate solution with strong stirring. It is also preferable to add the two reaction solutions simultaneously to an aluminosilicate slurry prepared in advance.

The reaction temperature is 50-90°C, preferably 60-80°C. If it is too low, coarse particles will occur, and if it is too high, crystallization will occur, both of which are undesirable. 50-90 inside the reactor
While keeping at ℃, mix with room temperature sodium silicate aqueous solution.
The best results were obtained when a supersaturated aqueous sodium aluminate solution at 50-90°C was simultaneously added. The reaction may be carried out either batchwise or continuously.

The time required for addition varies depending on the amount of preparation, but
10 to 180 minutes, preferably 15 to 60 minutes. It is desirable to continue stirring for an additional 10-60 minutes after the addition is complete to help homogenize the gel. Once gelation is complete
Raise the temperature to 70-110℃, preferably 80-100℃ and heat it for 15-15℃.
It is held for 120 minutes, preferably 20 to 60 minutes, during which crystallization of the aluminosilicate (zeolite 4A) occurs and a slurry is formed. At this time, if the crystallization time is too long or the temperature is too high, zeolite 4A may turn into hydroxysodalite without ion exchange properties.

In the above reaction, in order to reduce the viscosity of the reaction mixture, a suitable dispersant, e.g.
Polyacrylic acid polymers, copolymers, etc. may also be added. The slurry after crystallization can be added to the slurry base of the powder cleaning agent as it is or after neutralization if necessary. For neutralization, in addition to carbon dioxide gas, an unneutralized compound (S agent) of an anion activator that is a cleaning agent component (for example, unneutralized alkylbenzenesulfonic acid), etc. can be used. Carbon dioxide gas may be blown directly into the reaction tank, or may be mixed in a static mixer while being circulated. Furthermore, after partially neutralizing with carbon dioxide gas, neutralization can be further completed with an S agent.

Alternatively, the slurry may be dried and powdered and blended with the cleaning agent component.

By using the method of the present invention, an aluminosilicate that has excellent builder performance and provides good powder physical properties can be obtained directly as a concentrated slurry that can be used in the production of a detergent slurry.

The size of crystal grains obtained by the method of the present invention is
The average size is about 7μ, and the proportion of coarse particles is also small.
Therefore, there is almost no fear that the detergent builder will adhere to clothes when they are washed. Of course, if necessary, it can be further finely ground using a mill.

EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

In addition, in the examples, the calcium ion exchange capacity is the value after 10 minutes. In addition, all percentages indicate weight percent.

Example 1 Dissolve the reagent, 107.2 g of sodium hydroxide, in 70 g of water in a 500 ml round-bottom three-necked flask. After heating to 50°C, add 197.9 g of aluminum hydroxide with a moisture content of 8.8% and an average particle size of 50 μm, and stir. While doing so, the temperature rose.
After holding at the boiling point temperature for 20 minutes while refluxing and confirming that the entire amount has dissolved, the temperature is lowered to 90℃, and an additional 20g of room temperature water is added to create a uniform, thick, and
A viscous supersaturated solution of sodium aluminate was obtained. In another three-neck separable flat-bottomed flask, add No. 3 sodium silicate (Na ₂ O 9.42%, SiO ₂ 28.99
%, moisture 61.59%) in advance, and after raising the temperature to 80℃ in an oil bath, add the entire amount of the above-mentioned supersaturated sodium aluminate solution and No. 3 sodium silicate.
350g of each using a microtube pump.
Simultaneous additions were made at a constant rate for 60 minutes. This width is 9cm,
Stirring was continued at 500 rpm using a 9 cm long U-shaped stirring bar. The temperature of the aqueous sodium aluminate solution to be added was 70°C to 80°C, and the temperature of No. 3 sodium silicate was room temperature.

During gelation, the resulting sodium aluminosilicate gel temporarily hardened to the point where it became difficult to stir, but by continuing to add and stir, it was eventually possible to obtain a uniform, white, thick slurry. After the addition was completed, the mixture was kept warm and stirred for 30 minutes, then the temperature was raised to 100°C, and stirring was maintained for 60 minutes. After that, stirring was stopped, and the container was immersed in water at room temperature to be rapidly cooled. The composition of the mixed solution is Na ₂ O:
Al ₂ O ₃ :SiO ₂ :H ₂ O=1.69:1:2:23.

The resulting slurry is white and thick, but
It had good liquidity. The X-ray diffraction pattern of the obtained crystals was the same as that of zeolite 4A.
The crystallinity is determined by the diffraction line of d = 2.98 Å (hkl = 410,
322), the calculated relative intensity to the standard crystal (Linde-4A) was 94%. The ion exchange capacity of this product is 276.6 (mgCaCO ₃ /g of anhydrous zeolite), which is higher than commercially available zeolite for cleaning agents.
It was comparable to 271.6.

Classification using a water sieve resulted in particles of 200mesh on.
9.2% hot.

When 20% of the obtained slurry was mixed into an anionic activator-based phosphorus-free powder detergent fabric and dried, a detergent with good powder physical properties and detergency was obtained.

Example 2 In the same container as in Example 1, 150 g of the zeolite 4A slurry obtained in Example 1 was placed in advance, and to this was added 395.1 g of the sodium aluminate aqueous solution obtained in exactly the same manner as in Example 1. 500 g of sodium silicate was added simultaneously using a microtube pump. During this time, keep it at 80℃,
Stirring was carried out at 500 rpm using the same stirring blade as in Example 1. Continue stirring for an additional 20 minutes after the addition is complete, then
The temperature was raised to 100°C and stirring was continued at 300 rpm for 45 minutes. After the crystallization was completed, the container was placed in cold water for quenching. This made it possible to obtain a fluid, thick white slurry. The relative diffraction intensity of this crystal at d=2.98 Å was 88.7% of that of the standard sample. Further, the ion exchange capacity was 272.0 (mgCaCO ₃ /g anhydrous zeolite). Classification using a water sieve revealed that 200 mesh particles accounted for 13.2%. This slurry could be added directly into the powder detergent slurry base. The composition of the mixed solution is
The ratio _{of Na2O} : _Al2O3 : _SiO2 : _H2O was 1.69:1:2:23.

Example 3 Zeolite was prepared under the same conditions as in Example 1 except that 197.9 g of aluminum hydroxide was dissolved in 216 g of 48% sodium hydroxide aqueous solution, and the crystallinity was 96.8% and the ion exchange capacity was 276.1 mg/
A zeolite slurry with a particle size of 200mesh and 10.8% was obtained. This product could be added directly to the powder detergent slurry base. The composition _of the mixed solution is _Na2O : _Al2O3 : _SiO2 : _H2O =1.71:
The ratio was 1:2:23.8.

Example 4 Example 2 except that the time required for mixing sodium aluminate and sodium silicate was changed to 15 minutes.
Gelation and zeolite formation were carried out in exactly the same manner as above. The obtained zeolite had a crystallinity of 97.9% according to X-ray diffraction, an ion exchange capacity of 279.3 mg/g, and a particle size of 97.9%.
200mesh on 8.6%. This slurry could be added directly into the powder detergent slurry base. The composition of the mixed solution is Na ₂ O:
Al ₂ O ₃ :SiO ₂ :H ₂ O=1.69:1:2:23.

Example 5 Gelation and gelation were carried out in exactly the same manner as in Example 1, except that during the preparation of aluminosilicate gel, the temperatures of sodium aluminate, sodium silicate, and aluminosilicate gel slurry were maintained at 80°C, 100°C, and 80°C, respectively. It was converted into zeolite. The crystallinity of the obtained zeolite according to X-ray diffraction was 85.3%, and the particle size was
200mesh on particles accounted for 16.1%. The composition _of the mixed solution is _Na2O : _Al2O3 : _SiO2 : _H2O =1.69:
It was 1:2:23.

Example 6 158.7g of 243.1g of sodium hydroxide with a moisture content of 4.3%
dissolved in water. 448.7 g of aluminum hydroxide with a water content of 4.76% and an average particle size of 55 μm was added to this aqueous solution, and after the temperature was raised to 105°C and held for about 20 minutes, a yellow, transparent, and viscous sodium aluminate aqueous solution was obtained with foaming. .

Separately, 198.4 g of aluminosilicate gel prepared in advance was placed on the bottom of the vessel, and No. 3 sodium silicate (Na ₂ O 9.50%,
1133.8 g of SiO ₂ (29.00%) and the entire amount of the previously prepared aqueous sodium aluminate solution were simultaneously added dropwise over 60 minutes. 200g of aluminosilicate gel after addition
Specifically for the next synthesis, the remainder was stirred for an additional 15 minutes, then heated and held at 105°C for 20 minutes.

The resulting slurry was rapidly cooled with water to prevent formation of hydroxysodalite. In this way the concentration is 58%
We were able to obtain a 4A zeolite slurry.
Crystallinity by X-ray diffraction is 96%, ion exchange capacity is
It was 277.0 mg/g.

This was an excellent slurry that could be added into a powder detergent slurry base either as is or after neutralization. The composition of the mixed solution is
_Na2O : _Al2O3 : _{SiO2 : H2O} =1.70:1:2.00:
It was 22.1.

Example 7 64.3 g of sodium hydroxide with a moisture content of 4.3% was dissolved in 42.0 g of ion-exchanged water, and 118.7 g of aluminum hydroxide with a moisture content of 4.3% and an average particle size of 55 μm was added thereto, and after the temperature rose to the boiling point, it was held for 15 minutes to completely dissolve. I let it happen. When this was allowed to cool to room temperature, a slightly cloudy viscous liquid was obtained.

Separately, No. 3 sodium silicate (Na ₂ O 9.42%,
300 g of SiO ₂ (28.99%, moisture 69.57%) was placed in one flask, and the above sodium aluminate suspension was gradually added thereto using a dropping funnel over about 30 minutes, while stirring was continued. The resulting gel was stirred for 15 minutes, then heated to 90°C and held for 60 minutes.
The X-ray diffraction of the obtained slurry consists only of the diffraction lines of zeolite 4A, and the ion exchange capacity is 265 mg/g.
showed that. The composition of the mixed solution is Na ₂ O: Al ₂ O ₃ :
SiO ₂ :H ₂ O=1.70:1:2:22.1.

Example 8 A zeolite slurry was synthesized under exactly the same conditions as in Example 1 except that sodium aluminate was added during preparation and the amount of water added was changed from 20 g to 130 g.
A zeolite slurry of 249 mg/g was obtained. The composition _of the mixed solution is _Na2O : _Al2O3 : _SiO2 : _H2O =1.69:
It was 1:2:28.0.

Example 9 Sodium aluminate (Al ₂ O ₃ 35.9%,
57.2g of _Na2O24.4 %, _H2O39.7 %) with ion-exchanged water
27.1g, and preliminarily added 100g of No. 2 sodium silicate (Na ₂ O 14.5%, SiO ₂ 35.0%, H ₂ O 50.5
%) was added to a 500 ml three-neck flask lined at the bottom with stirring. 15 minutes after the white sodium aluminosilicate gel was formed, the temperature was raised to 105°C and held for 30 minutes. It was confirmed by X-ray diffraction that the obtained slurry was zeolite 4A with good crystallinity. The composition of the mixed solution is Na ₂ O:
Al ₂ O ₃ :SiO ₂ :H ₂ O=1.84:1:2.1:26.6.

Example 10 A thick white slurry could be synthesized in the same manner as in Example 9, except that a solution of 64.47 g of sodium aluminate/24 g of water was added to 125 g of No. 2 sodium silicate. This material was confirmed to be zeolite 4A with good crystallinity by X-ray diffraction. The composition of the mixed solution _{is Na2O} : _Al2O3 :
SiO ₂ :H ₂ O=2.0:1:2.5:29.4.

Next, a comparative example is shown, and the composition of the mixed solution is shown in parentheses.

Comparative example 1 (Na ₂ O: Al ₂ O ₃ : SiO ₂ : H ₂ O=1.55:1:
1.70:23.0) In a 500ml three-necked flask, 120.3g of sodium hydroxide with a water content of 4.3% was dissolved in 161.6g of water, and the temperature was raised to 50°C. 232.4 g of aluminum hydroxide with a moisture content of 4.7% was added to this, the temperature was raised while stirring, refluxed for 20 minutes at the boiling point temperature, and after confirming that the entire amount had dissolved, the mixture was cooled to 90°C to form a homogeneous, thick, and viscous aluminic acid. A sodium supersaturated solution was obtained.

In a separate container, put 150g of No. 3 sodium silicate solution (9.42% Na ₂ O, 28.99% SiO ₂ , balance H ₂ O) in advance, and after raising the temperature to 80°C, mix it with the above-mentioned supersaturated sodium aluminate solution. , No. 3 sodium silicate 350g
were added simultaneously over a period of 60 minutes. During this time, stirring was carried out in exactly the same manner as in Example 1. After aging the resulting gel composition for 30 minutes while stirring,
It was held at 105°C for 60 minutes. Stirring was continued during this time. Stirring was stopped and the container was immersed in water at room temperature to be rapidly cooled. The X-ray diffraction pattern of the resulting slurry showed good crystallization of zeolite 4A.

The ion exchange ability of this product is after washing and filtration.
It was 280.0 (mgCaCO ₃ /g anhydrous zeolite).

However, by mixing 20% of this slurry into a phosphorus-free powder detergent fabric containing an anionic surfactant as the main ingredient,
When clothes were washed using the detergent obtained by drying, coarse insoluble gel was found adhering to the clothes, making it unsuitable for use as a detergent.

Comparative example 2 (Na ₂ O: Al ₂ O ₃ : SiO ₂ : H ₂ O=1.33:1:
2.11:24.0) Synthesis of sodium aluminosilicate was attempted using the same raw materials and the same method as in Comparative Example 1. 63.6g of sodium hydroxide was dissolved in 100g of water, 187.4g of aluminum hydroxide was added thereto, and the mixture was heated to boiling point. Reflux was continued for about 1 hour, but some remained undissolved. This partially suspended supersaturated sodium aluminate solution was mixed with a total of 500 g of No. 3 sodium silicate under the same conditions as in Example 1 to obtain a white gel. This was crystallized and rapidly cooled in the same manner as in Example 1 to obtain a viscous crystalline slurry containing many coarse particles. When 20% of this product was mixed into an anionic surfactant-based phosphorus-free powder detergent fabric and dried, the resulting powder detergent had poor powder fluidity and poor cleaning power, making it unusable. It was hot.

Comparative example 3 (Na ₂ O: Al ₂ O ₃ : SiO ₂ : H ₂ O=2.01:1:
3.03:29.8) Sodium aluminate was prepared using the same raw materials as in Example 1 using 50.0 g of water, 67.2 g of sodium hydroxide, and 136.4 g of aluminum hydroxide under the same conditions as in Example 1 to obtain a transparent viscous solution. Ta. Under the same conditions as Example 1, No. 3 sodium silicate 500
By mixing with g and crystallizing, a concentrated slurry of crystalline sodium aluminosilicate could be obtained. When 20% of this was mixed into an anionic surfactant-based phosphorus-free powder detergent fabric and dried, a powder detergent with good powder properties could be obtained, but the detergency was insufficient and it could not be used. I couldn't stand it.

Comparative example 4 (Na ₂ O: Al ₂ O ₃ : SiO ₂ : H ₂ O=2.27:1:
2.43:28.3) Water 103.8 using the same raw materials and under the same conditions as Comparative Example 1
g, 119.0 g of sodium hydroxide, and 170.2 g of aluminum hydroxide were mixed and dissolved to obtain a transparent supersaturated sodium aluminate solution. This was mixed with 500 g of No. 3 sodium silicate to form a gel in the same manner as in Example 1, and crystallized to obtain a concentrated slurry of crystalline sodium aluminosilicate. When 20% of this product was mixed directly into an anionic surfactant-based phosphorus-free detergent fabric, it showed extremely poor powder properties. In addition, if this slurry is neutralized with carbon dioxide gas or the acid radicals constituting the salts contained in the detergent dough, and then mixed at 20% into the same detergent dough, the powder physical properties will improve, but the cleaning ability will be reduced. There was a decrease in the temperature, and all of them were unusable.

Claims (1)

[Claims] 1. 30 to 70% by weight aluminic acid so that the composition of the mixed solution has a molar ratio of 1.5 to 2.0 _{Na 2} O: 1 Al ₂ O ₃ : 2.0 to 2.5 SiO ₂ : 15 to 30 H ₂ O. A method for producing a crystalline aluminosilicate slurry for detergent formulation, which comprises mixing and gelling a sodium aqueous solution and a 35-50% by weight aqueous sodium silicate solution, and then crystallizing at 70-110°C. 2. Claim 1, wherein the 30 to 70% by weight aqueous sodium aluminate solution is obtained by dissolving aluminum hydroxide in an aqueous sodium hydroxide solution.
A method for producing a crystalline aluminosilicate slurry for detergent formulation as described in .