JPS6246494B2 - - 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 Japanese Patent Application Laid-Open No.
(See Publication No. 12381, etc.) As for aluminosilicates, their cation exchange ability has been well known for a long time, and their synthesis methods have also been described, for example in patent no. 237383.
It is well known as can be seen in the No. 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.

The next ideal would be to mix the alumina and silica sources to form an aluminosilicate gel, which would then be crystallized and simultaneously added to the powder slurry base and dried.

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 and has excellent Hilder performance, and also has excellent powder physical properties when made into a powder detergent. was previously unknown. Therefore, the present inventors conducted extensive research in order to find a method for producing aluminosilicate that satisfies the above conditions.The inventors first used a sodium aluminate aqueous solution and a sodium silicate aqueous solution each having a high concentration within a specific range, and then mixed them. It was discovered that an aluminosilicate slurry with excellent performance could be obtained by adjusting the composition of the mixed solution within a specific range to produce an aluminosilicate slurry (Japanese Patent Application No. 137096/1983).
Furthermore, as a result of research, by changing the composition of the above mixed solution and selecting it within another specific range adjacent to the specific range found earlier, it was found that it was easier to grind and had better fluidity.
It was discovered that an aluminosilicate slurry having excellent suspension stability and a fine particle size can be obtained, and the present invention was achieved.

That is, in the present invention, the composition of the mixed solution has a molar ratio; SiO ₂ /Al ₂ O ₃ ≧2.0, Na ₂ O / Al ₂ O ₃ > 2.0 and (SiO ₂ +Na ₂ O) / Al ₂ O ₃ ≦4.5, H _2O ／ _Al2O3 = ₁₅
A detergent formulation characterized by mixing and gelling a 30 to 70% by weight aqueous sodium aluminate solution and a 35 to 50% by weight aqueous sodium silicate solution, and then crystallizing at 70 to 110°C, as in the range of ~30°C. The present invention provides a method for producing a crystalline aluminosilicate slurry for industrial use.

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 above aqueous solution is too small, the concentration of the slurry produced will also be low 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 it may also be used as a cleaning agent. The physical properties of the powder deteriorate when mixed. Furthermore, if the sodium silicate aqueous solution exceeds 50% by weight, homogeneous mixing is impossible.

Also, regarding the composition of the mixed solution, the amount of SiO ₂
If the amount is less than 2.0 times mole relative to Al ₂ O ₃ , the water-soluble aluminum salt will remain in the aluminosilicate and interact with the surfactant, which is a detergent component, which is undesirable. This is undesirable because it also reacts with soda and forms an insoluble gel that may adhere to clothes during washing. Also, Na ₂ O
If the amount of SiO 2 exceeds 2.0 times the mole of Al ₂ O ₃ , the powder physical properties and cleaning properties of the cleaning agent will tend to decrease slightly, but the amount of SiO ₂ can be reduced according to the amount of Na ₂ O,
When controlling the ratio within the range of (Na ₂ O + SiO ₂ )/Al ₂ O ₃ ≦4.5, there are no particular problems, and a cleaning agent that is sufficiently durable for practical use can be obtained. Even when the amount of Na ₂ O is 2.0 mol or less relative to Al ₂ O ₃ , the resulting cleaning agent has excellent physical properties and performance, but due to the special cleaning method, the particle size of the zeolite must be adjusted in particular. When it is necessary to grind finely, it is advantageous to increase the amount of Na ₂ O by more than 2.0 times the amount of Al ₂ O ₃ by mole, as this makes it easier to grind and gives a product with excellent fluidity and suspension stability. It is.

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 components.

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 proportion of coarse particles is small and it becomes fine (200mesh
It has excellent fluidity and suspension stability, and there is almost no fear of it adhering to clothes when washing them as a detergent builder. Of course, if necessary, it can be easily ground even more finely 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 In a 500ml round bottom flask, dissolve 147.0g of sodium hydroxide (water content 4.3%) in 112.7g of water and add 50%
After raising the temperature to °C, 196.8 g of aluminum hydroxide having a moisture content of 4.7% and an average particle size of 50 μm was added, and the temperature was raised while stirring. After maintaining the solution at the boiling point temperature for 20 minutes while refluxing and confirming that the entire amount had dissolved, the temperature was lowered to 50°C to obtain a uniform, thick, and viscous supersaturated solution of sodium aluminate. Another three-piece separable 1
In a flat bottom flask, add 150 g of No. 3 sodium silicate (Na ₂ O 9.42%, SiO ₂ 28.99%, water 61.59%).
was added in advance, and after raising the temperature to 50°C in an oil bath, the entire amount of the above-mentioned supersaturated sodium aluminate solution and 350 g of No. 3 sodium silicate were added simultaneously at a constant rate for 30 minutes using a microtube pump. During this time, stirring was continued at 500 rpm using a U-shaped stainless steel stirring rod with a width of 9 cm and a length of 9 cm. The temperature of sodium aluminate to be added is 50
℃, and the temperature of No. 3 sodium silicate was room temperature.

The resulting sodium aluminosilicate temporarily became hard, but as stirring continued, it became a slurry with good fluidity. After the addition was completed, stirring was maintained for 30 minutes, then the temperature was raised to 70°C, and stirring was continued. temperature increase 60
After a few minutes, stirring was stopped, and the container was rapidly cooled in water at room temperature. The composition of the mixed solution is Na ₂ O:
Al ₂ O ₃ :SiO ₂ :H ₂ O=2.10:1:2.01:24.6. The resulting slurry was white and had good fluidity. The X-ray diffraction pattern of the obtained crystal is the same as that of zeolite 4A, and the relative intensity of the diffraction line at d = 2.98 Å (hkl = 410, 322) with respect to the standard crystal (Linde 4A) is calculated to be 92%.
It was hot. The ion exchange capacity of this product is 274.3 (mg
CaCO ₃ /anhydrous zeolite g), which was comparable to 271.6, a commercially available zeolite for cleaning agents.

Classification using a water sieve revealed that 3.2% of particles were 200mesh on.

The resulting slurry was diluted with carbon dioxide to pH 10.9 (80 g of water).
After neutralizing to 0.2g of slurry (value obtained when 0.2g of slurry is added to), a 20% anionic activator-based phosphorus-free powder detergent was mixed into the fabric and dried, resulting in a detergent with good powder properties and detergency. did it.

Example 2 In the same manner as in Example 1, 137.5 g of sodium hydroxide (4.3% water) was dissolved in 124.8 g of water, and 195.8 g of aluminum hydroxide (4.7% water) was added to this in a heated state.
g was added to obtain a supersaturated solution of sodium aluminosilicate. 150g of this No. 3 sodium silicate (Na ₂ O 9.42%, SiO ₂ 28.99%, water 61.59%)
In the same manner as in Example 1, the mixture was added together with 346.7 g of sodium silicate into a flask in which the mixture had been previously placed, and a thick white slurry could be obtained by aging, heating, and cooling. The composition of _this mixed solution is _Na2O : _Al2O3 : _SiO2 : _H2O =2.01:1:2.01 in molar ratio.
It was 25.07. The X-ray pattern of the obtained crystals matched that of zeolite 4A. When the crystallinity was checked in the same manner as in Example 1, it was 95.4%. Ion exchange capacity is 277 (mgCaCO ₃ /g anhydrous zeolite)
It was comparable to commercially available zeolite.

After neutralizing the obtained slurry in the same manner as in Example 1,
When the detergent powder was mixed into fabric, a good detergent could be obtained.

In addition, when the obtained slurry was classified using a water sieve, 4.6% of particles with a size of 200 mesh were observed.

Example 3 Sodium hydroxide (4.3% water) 188.5g, water
154.1g, aluminum hydroxide (moisture 8.8%) 206.7
g, No. 3 sodium silicate (Na ₂ O 9.42%,
A white viscous slurry was obtained in exactly the same manner as in Example 1, except that 500 g of SiO ₂ (28.99%, moisture 61.59%) was used. In addition, the mixed gel composition at this time is expressed in molar ratio.
_Na2O : _Al2O3 : _{SiO2 : H2O} =2.50:1:2.00:
It was 27.3. The ion exchange capacity of this product is 276.4
(mgCaCO ₃ /g anhydrous zeolite). A powder detergent obtained by mixing 20% of the anionic detergent into the fabric after carbon dioxide neutralization as in Example 1 showed good powder physical properties and detergency.

Example 4 The same raw materials as in Example 3 were used, and the amounts used were 151.0 g of sodium hydroxide, 57.65 g of water, 190.5 g of aluminum hydroxide, and 500 g of No. 3 sodium silicate, under the same conditions as in Example 1. A white viscous slurry was obtained. The mixed gel composition at this time was Na ₂ O: Al ₂ O ₃ : SiO ₂ : H ₂ O = 2.31:1 in molar ratio.
2.17: It was 24.0. The ion exchange capacity of this substance is
257 (mgCaCO ₃ /g dry solid content), and when it was neutralized in the same manner as in Example 1 and mixed into a detergent fabric to make a powder detergent, a product that could withstand use in both powder physical properties and detergent properties was obtained. It was done.

Example 5 The raw materials and conditions used were the same as in Example 3, and the amounts used were 118.7 g of sodium hydroxide, 179.7 g of aluminum hydroxide, 94.2 g of water, and 500 g of No. 3 sodium silicate.
As g, gelation and crystallization were performed to obtain a white viscous slurry. The mixed gel composition at this time was Na ₂ O: Al ₂ O ₃ : SiO ₂ : H ₂ O = 2.08:1 in molar ratio.
2.30: It was 26.7. This was neutralized in the same manner as in Example 1, and then mixed into detergent fabric to make a powdered detergent, which resulted in satisfactory powder properties and detergency.

Comparative Example 1 Using the same raw materials and under the same conditions as in Example 1, 237.1 g of sodium hydroxide, 230.3 g of water, 245.7 g of aluminum hydroxide, and 500 g of No. 3 sodium silicate were mixed and gelled, and crystallization was performed. A thick slurry of sodium aluminosilicate was obtained. The mixed gel composition at this time is Na ₂ O: Al ₂ O ₃ : SiO ₂ : in molar ratio.
_H2O =2.40:1:1.61:25.6. After neutralizing this material in the same manner as in Example 1, apply 20% to the detergent fabric.
The detergent mixed and dried had extremely poor washability.

Comparative Example 2 Using the same raw materials as in Example 3 and under the same conditions as in Example 1, 219.4 g of sodium hydroxide, 121.9 g of water, 205.7 g of aluminum hydroxide, and 500 g of No. 3 sodium silicate were mixed and gelled, and crystallized. A concentrated slurry of crystalline sodium aluminosilicate was obtained. In addition, the mixed gel composition at this time is expressed in molar ratio.
_Na2O : _Al2O3 : _SiO2 : _{H2O =} 2.82:1:2.01:
It was 26.3. After neutralizing carbon dioxide gas in the same manner as in Example 1, add 20% of this product to the phosphorus-free anionic detergent fabric
The powder detergent obtained by mixing has poor powder fluidity,
Moreover, the washability was insufficient.

Comparative Example 3 Using the same raw materials and under the same conditions as Comparative Example 2, 119.0 g of sodium hydroxide, 170.2 g of aluminum hydroxide, and water were used.
103.8 g and 500 g of No. 3 sodium silicate were mixed, gelled, and crystallized to obtain a concentrated slurry of crystalline sodium aluminosilicate. The mixed gel composition at this time is Na ₂ O: Al ₂ O ₃ : SiO ₂ : in molar ratio.
_H2O =2.27:1:2.43:28.3. This was neutralized in the same manner as in Example 1, mixed at 20% into phosphorus-free detergent fabric, and dried to produce a powdered detergent, which had poor powder physical properties and unsatisfactory washability.

Claims (1)

[Claims] 1. The composition of the mixed solution has a molar ratio; SiO ₂ /Al ₂ O ₃ ≧2.0, Na ₂ O/Al ₂ O ₃ >2.0, and (SiO ₂ +Na ₂ O)/Al ₂ O ₃ ≦4.5. , H ₂ O/Al ₂ O ₃ = 15
A detergent formulation characterized by mixing and gelling a 30 to 70% by weight aqueous sodium aluminate solution and a 35 to 50% by weight aqueous sodium silicate solution, and then crystallizing at 70 to 110°C, as in the range of ~30°C. A method for producing crystalline aluminosilicate slurry for use. 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 .