KR100724765B1 - Method for manufacturing the fine particles of lsx type zeolite and usage of that zeolite as builder component in detergent composition - Google Patents

Abstract

The present invention provides a method for preparing LSX type zeolite microparticles which are useful as builders for detergents because the pore inlet is larger than type A zeolite, and the Si / Al ratio is 1.1 or less and the crystal grain size is about 2 having a FAU structure. Provided is a detergent composition having excellent cleaning performance, containing LSX zeolite microparticles composed of 70 to 100 mol% of Na ions and 0 to 30 mol% of K ions in a cation as a detergent builder.

Zeolite, Detergent Builder, Fine Particles

Description

Manufacturing method of LS-type zeolite microparticles and use as a builder for detergent of LS-type zeolite microparticles produced in this way

1 is a schematic flowchart of a synthesis process of LSX type zeolite crystal grains.

2 is an X-ray diffraction (XRD) analysis pattern of the LSX zeolite according to the present invention.

FIG. 3 shows LSX zeolite crystals [Sample 1 (b)] and LSX zeolite crystals [Sample 2 (c) and Sample 3 (commercially available) prepared by commercial A-4 zeolite (a) and the conventional production method. d)] is a SEM photograph taken with a scanning microscope.

The present invention relates generally to a method for microparticulating X-type zeolites and to the use of X-type zeolite microparticles prepared as a builder for detergents. More specifically, the present invention relates to an X-type zeolite that is effective as a builder for detergents, in particular, having a pore inlet larger than that of A-type zeolite, and particularly, a method and use of LSX zeolite having a low particle size and uniform particle size. .

Currently zeolites are widely used as ion exchangers, catalysts, adsorption (dehydration) and the like. Zeolite is connected to SiO ₄ tetrahedron as a basic unit, and part of Si may be substituted with metal elements such as Al, Ga, Ti, and the like. The structure and characteristics of the zeolite greatly vary depending on how the basic structural units are arranged. Sodalite units consist of six squares and eight hexagons. The sodalite unit is closely interlocked with the SOD structure, and the quadrangular surface of the sodalite is combined to form a double ring, which is called an LTA structure. In the sodalite, the hexagonal surface is made of a double-hexagonal ring, which is called a FAU structure, and the X, Y, and LSX zeolites belong to this.

When a part of tetrahedron of Si-O _{4 which} is a basic unit is substituted with tetrahedron of Al—O ₄ , cations such as Na + are bonded to maintain electrical neutrality. The cation in the zeolite is easily exchanged with other cations present in solution. This is called ion exchange capacity. Using this nature Ca ^{2 +} in the wash, to effectively remove the Mg ^{+ 2} through the ion-exchange is used as a useful zeolite to increase the washing effect.

Hard water and soft water are distinguished by the concentration of magnesium and calcium ions in the water. Normally, 100 mg of water contains 1 mg of calcium oxide, and the intensity is set at 1 degree, and magnesium is calculated by converting it into calcium (1.4 mg of magnesium oxide = 1 mg of calcium oxide). A hardness of 20 degrees or more is hard water, and a hardness of 10 degrees or less is called soft water. Groundwater is usually close to hard water because of its large strength, and rainwater is often soft because of its small strength. Hard water does not foam well when soap is used, reducing the cleaning effect. Zeolite exchanges calcium ions (Ca ²⁺ ) and magnesium ions (Mg ²⁺ ) in water with sodium ions (Na ⁺ ) to convert hard water into soft water, which enhances the washing effect during washing. For this purpose, zeolite is used as an additive, that is, a builder, which makes up 40 to 50% of the synthetic detergent. In addition, zeolite is effective as a builder for detergents because it prevents reattachment of dirty components from fibers through surfactants and absorbs moisture in the air to help detergents stay in a smooth state without being entangled with each other.

Zeolites for use as detergent builders require a high ion exchange capacity. The large ion exchange capacity means that a large amount of cations may exist in the structure only when Si is substituted with Al in the structure of the zeolite. The presence of a large number of cations means that the effect of lowering the hardness through ion exchange is great. The degree can be expressed by the ratio of Si / Al, and a lower Si / Al ratio means more ion exchange sites. Washing is usually done around 10-20 minutes. In addition, rather than using hot water or hot water, low-temperature water of 10-25 ° C is mainly used. Thus, zeolites with faster ion exchange rates at lower temperatures exhibit higher effects. It is known that the smaller the size of the zeolite, the wider the outer surface area and the easier the ions enter and exit. Thus, the smaller the size of the crystal grain, the smaller the size of the zeolite is known to be excellent as a builder for detergents. (Science and Applications of Zeolites, Tokyu Co., Ltd., Japan (1987)).

 As the LTA type zeolite has a value close to the theoretical minimum value of 1.0, the ratio of Si / Al has the largest number of ion exchange sites per unit mass, so it has excellent adsorption and ion exchange characteristics, and various mass synthesis methods are commercialized. It is also used as a detergent builder because it is inexpensive.

On the other hand, in the FAU structure, the inlet of the pore is 12-membered ring, unlike the pore inlet of the LTA structure is composed of 8-membered ring. While the pore inlet diameter of the LTA structure is about 0.4 nm, the pore inlet of the FAU structure has a size of 0.7 nm or more. FAU structure is divided into three types according to Si / Al ratio. Si-Al ratios of 1.5 to 3.0 are classified into Y zeolites, 1.0 to 1.5 of X zeolites, and those close to 1.0 are classified into LSX (Low Silica X) zeolites. Generally, commercially available X-type zeolites and Y-type zeolites are commercially available as adsorbents and catalyst materials, but their effectiveness as a detergent builder is low due to the high Si / Al ratio and fewer ion exchange sites.

LSX zeolites having a Si / Al ratio close to 1.0 require relatively precise control of synthesis conditions such as raw material composition, temperature, and time, and are known to be difficult to form small crystal grains and have a long synthesis time. Therefore, until recently, although the commercial use was small, high performance as an adsorbent for oxygen PSA is newly recognized, and the commercialization research is being actively conducted in recent years. (Kim Jin-bae, Preparation of Binderless Li-LSX Adsorbent for Oxygen PSA: J. Korean Ind. Eng. Chem., Vol. 15, No. 1, February 2004.81-85 (2004)).

Accordingly, the present inventors have completed the present invention as a result of earnestly studying a method for producing LSX zeolite that can be used as a builder for detergents due to a low Si / Al ratio and a large pore inlet and excellent ion exchange ability.

It is an object of the present invention to have a FAU structure, low Si / Al ratio, large pore inlet, excellent ion exchange ability, and a LSX type that can be manufactured in a short time with the size of crystal grains commercially available as a builder for detergent in a detergent composition. It is to provide a method for producing zeolite microparticles.

These and other objects of the present invention will be apparent from the following detailed description.

According to a first aspect of the present invention, (i) water and an alkali raw material are sequentially added to an aluminum source, stirred and mixed, and then the mixture is cooled and a silica raw material is slowly added thereto, wherein the raw material is SiO ₂ , Al ₂ O ₃ , The mixing molar ratio of M ₂ O (Na ₂ O + K ₂ O), K ₂ O / M ₂ O and H ₂ O is 1.00: (0.5-0.6) :( 2.8-3.5) :( 0.2-0.3) :( 60 to 70); (ii) heating the mixture to 40 ° C.-90 ° C. to crystallize within 24 hours; (iii) washing the resulting crystal grains and then drying them; And (iv) an ion exchange step of increasing the content of Na ions by repeating the resulting crystal grains in 1 ~ 3 M NaCl aqueous solution for 1 to 3 times at 60 ° C. to 100 ° C. for 1 to 3 times. , LSX zeolite composed of 70 to 100 mol% of Na ions and 0 to 30 mol% of K ions in a cation with a Si / Al ratio of 1.1 or less and a crystal grain size of about 2 μm or less while having a FAU structure Provided are methods for preparing the particles.

In a preferred embodiment of this embodiment, the mixing molar ratio of the raw material SiO ₂ , Al ₂ O ₃ , M ₂ O (Na ₂ O + K ₂ O), K ₂ O / M ₂ O and H ₂ O is 1.00: 0.57 It is preferable that it is: 3.25: 0.25: 65.

In addition to these mixing ratios, the inventors have found that the Si / Al molar ratio is 1.1 or less, and the crystal grain size is about 2 μm or less. It was found that the type zeolite can be produced and the optimum conditions can be identified.

In more detail, in the method for producing LSX zeolite particles of the present invention, there is no particular limitation on the silica raw material and the aluminum raw material that can be used. For example, commercially available silica colloidal silica, sodium silicate aqueous solution (water glass), and the like may be used. Aluminum raw materials may also use commercially available sodium aluminate.

In the production method of the present invention, the addition order of the raw material components is mixed with an aluminum raw material and water, such as distilled water, and then mixed in the order of alkali sources such as NaOH and KOH. At this time, the temperature of the mixture is raised to about 60 to 70 ℃ due to the heat of reaction, thereby cooling the temperature of the solution to about 40 ℃. When the mixed solution is cooled as described above, the silica raw material is slowly added while stirring the mixed solution at a speed of 300 rpm or more.

After mixing, the crystallization may be performed by standing in a constant temperature bath at 40 ° C. for about 4 days as in the conventional LSX type zeolite manufacturing method, or by increasing the temperature. For example, after making it react at 40 degreeC for 5 to 10 hours, it can heat up from 60 degreeC to 90 degreeC gradually over 10 to 15 hours. It is also possible to use a method in which the obtained crystal grains are added before crystallization as a small amount of seed. Among these crystallization methods, the second and third methods have been shown to be desirable to reduce the size of the crystals and to achieve high ion exchange performance in low temperature (eg 0 ° C.) and short time (5 minutes).

After crystallization, the crystal grains are collected using a vacuum filter or the like, washed until the pH of the washing liquid is 9.5 or less, and then dried.

Finally, by repeating the process of 1 to 5 times at 1 ~ 3M NaCl aqueous solution in 1 ~ 3M NaCl aqueous solution 1 to 3 times to perform the ion exchange step to increase the content of Na ions by the present invention LSX zeolite microparticles of can be obtained.

The zeolite particles of the present invention prepared as described above were confirmed to be X-type zeolites having a FAU structure exhibiting a pattern substantially the same as the X-ray diffraction pattern of the known X-type zeolite by X-ray diffraction (XRD) analysis. (Fig. 2).

In addition, the shape and size of the X-type zeolite crystal particles according to the present invention were observed by scanning electron microscopy (SEM). According to the synthetic conditions, the size of the crystal was adjustable in the range of about 1 to 5 μm and the shape was spherical. (Fig. 4 (b)-(d)).

LSX-type zeolite particle of the present invention LSX type and by ion-exchange the Ca ^{2 +} ions of Na ⁺ ions with an aqueous solution that is contained in each zeolite comparison and analysis of the ion exchange capacity intended for A-type zeolite, on behalf of the A-type zeolite The possibility of zeolite as a builder for detergents can be confirmed.

The LSX zeolite identified as described above may be mixed with conventional surfactants to provide an improved ion exchange ability to provide a detergent composition exhibiting excellent washing ability, particularly high washing ability at low temperature and in a short time.

Therefore, the present invention has a Si / Al ratio of 1.1 or less while having a FAU structure as a second embodiment, the crystal grain size is about 2 μm or less, Na ions in the cation is 70 to 100 mol%, K ions are 0 to Provided is a detergent composition containing LSX zeolite microparticles composed of 30 mol% as a builder for detergents.

Such detergent compositions containing LSX-type zeolite microparticles of the present invention is particularly early, that is Ca ^{2 +} and Mg ^{2 +} ion exchange capacity is excellent in about 5 minutes, in particular K ⁺ finely ions are ion-exchanged with Na ⁺ ions particle Ca ^{2 +} and Mg ^{2 +} ion exchange capacity was found to be superior compared to the ion exchange capacity of the conventional Na-a.

Example

The present inventors found that LSX zeolite having a low Si / Al ratio can be manufactured by varying the synthesis conditions as described above, and after synthesizing three LSX zeolites, by ion-exchange the Ca ^{2 +} ions in the Na + ion and an aqueous solution contained in the zeolite, compared and analyzed the ion exchange capacity, on behalf of the a-type zeolite examined the possibility whether as a builder for detergents of LSX type zeolite.

Example  1: 3 kinds of heating conditions LSX Preparation of Type Zeolite

The raw material composition was used in a mixing ratio as shown in Table 1 below to prepare an LSX zeolite having a Si / Al ratio of 1.0.

Sodium aluminate (Ecopro _{products, 23.62wt% Al 2 O 3 -} 18.69wt% Na 2 O - 57.69wt% H 2 O solution), and stirred while distilled water was added to the reaction vessel wherein the ratio by mol of NaOH (Duksan product, 96% ) And KOH (85% from Duksan) were injected and stirred together.

The solution whose temperature rose to about 60 to 70 ° C. due to the heat of mixing was cooled to about 40 ° C. When the mixed solution is cooled while stirring with a strong rate of 300rpm, the sodium silicate solution was added slowly (product _{Ecopro, 29wt% SiO 2 - - 9.04wt} % Na 2 O 61.96wt% H 2 O) , and to proceed until the gelled It was left for a minute and then placed in an airtight container.

Sample 1 was crystallized by incubation for 4 days in a 40 ° C incubator according to the conventional LSX zeolite synthesis method. After crystallization, the sample was filtered using a vacuum filter, and washed with distilled water until the pH of the washing solution reached 9.5 or less in order to remove NaOH and KOH adsorbed on the crystal grains, and then in a 100 ° C. dryer for 10 to 15 hours. Dried. A schematic process diagram of LSX type zeolite synthesis is shown in FIG. 1.

After mixing the raw materials, Sample 2 added about 0.3 wt% of the raw material (about 2-3 wt% based on the mass of the final crystal grains produced) as a seed and held at 40 ° C for 10 hours. It crystallized at 80 degreeC for 14 hours.

Sample 3 was added to about 0.3wt% content of the raw material as a seed after mixing the raw materials, and after holding at 40 ℃ for 5 hours, the temperature was gradually raised over 40 hours from 90 ℃ to 40 ℃ Stirring was continued at a rate of about 50 rpm.

 As described above, after synthesis of three LSX zeolite samples 1, 2, and 3, X-ray diffraction analysis (XRD) was performed to confirm the crystal state, and all the samples showed almost the same XRD pattern as in FIG. The structure was well established.

In addition, the shape and size of crystal grains were observed using the scanning electron microscope. SEM photographs of 4-A zeolite (Na-A) and three types of samples used as comparative groups are shown in FIG. 3. The crystal size of commercially available Na-A (Fig. 3-a) was about 2 ~ 5㎛, Sample 1 (Fig. 3-b) synthesized by the conventional LSX zeolite synthesis method is made by relatively large crystal grains of about 5㎛ Samples 2 (Fig. 3-c) and 3 (Fig. 3-d) produced LSX particles of very small size on the order of 0.5-2.0 μm. However, in Sample 2, many small primary particles were aggregated to form large agglomerates. Even in Sample 3, some aggregation was observed, but it was relatively well dispersed.

Example  2: Ion exchange capacity  Measure

To Example 1 three kinds of zeolite synthesized in measuring the Ca ^{+ 2} ion-exchange capacity of (samples 1, 2 and 3), to prepare a solution of a concentration of 850 ppm Ca ^{2 +} CaCl ₂ using the reagents. The ion exchange temperature was set at 0 ° C. or 30 ° C. and 100 ml of CaCl ₂ aqueous solution (Ca 850 ppm) was added to the beaker, followed by stirring until the set temperature was the same as the temperature of the aqueous solution. After the temperature reached the set temperature, 1 g of zeolite sample was added to the solution, stirred for 5 minutes and 10 minutes, and then centrifuged. Harvesting a solution other than the zeolite precipitated by ICP-AES (TJA IRIS Advantage) Ca 2 +, in the solution with K ^+, Na ⁺ concentrations, and was measured. At this time, Na-A zeolite was used as a comparative group. Table 2 and Table 3 show the results of ion exchange at 0 ° C and 30 ° C, respectively.

The sample obtained in Example 1, both of them are contained K ⁺ ions to about 20 to 30 mol% in addition to Na ⁺ ions, K ⁺ ions can be caused to slow down the ion exchange rate because the large ionic relative to Na ⁺ ions have. Therefore, in order to replace the K ⁺ ions contained in Samples 1 to 3 with Na ⁺ ions, which are easily ion exchanged, the ion exchange at 80 ° C. using 1 N NaCl solution was repeated three times to be contained in the zeolite sample. Samples were prepared by exchanging most of the K ⁺ ions with Na ⁺ ions, and separated by attaching the symbol -Na after each sample number.

Compared to the initial Ca ² in the solution used for the ion exchange ⁺ ion concentration of about 830 ppm it can be seen that a Ca ^{2 +} ion concentration decreased after the ion-exchange in both the 4 types of zeolites. It reduced the 30 ℃ when Ca ^{2 +} ion concentration than 0 ℃ in all samples significantly it can be seen that the concentration of Na ⁺ ions increase. It can be seen that Samples 1, 2, and 3 are generally superior in ion exchange capacity at 0 ° C. than commercially available Na-A zeolites. In the case of samples 1, 2, and 3 containing K ⁺ ions, the ion exchange was not as good as that of Na-A zeolite at 30 ° C. However, most of the K ⁺ ions were replaced with Na (samples 1-Na, In case of Sample 2-Na and Sample 3-Na), the ion exchange rate was much faster than Na-A even at 30 ° C.

On the other hand, it exhibited a result of the ion exchange experiments in addition to Mg ^{2 +} Ca ^{2 +} ion as to increase the hardness of water decreases the cleaning effect in Table 4. For the Na + ion-exchanged with any sample is much faster than in Na-A Mg ^{2 +} showed the ion-exchange properties, particularly the particle size small sample 2 and sample 3, it was confirmed that its effect is very large.

It was synthesized by supplementing the size and synthesis rate of the crystal grains of LSX zeolite as a builder for detergents. Conventional methods could reduce the synthesis time, which took several ten hours, to about 15 hours, and could produce small particles of about 0.5 ~ 2.0 ㎛ in size.

The results obtained in this experiment show that the LSX zeolite, which has a small particle size and low agglomeration of primary crystal grains, is suitable as a builder that needs to be ion-exchanged within a short time even at low temperature due to the characteristics of washing. The improvement of ion exchange performance is expected to contribute to the good washing effect and the saving of detergent, and contributing to the saving of water resources and the reduction of environmental pollution.

Claims (4)

(i) Water and an alkali raw material are added to the aluminum source in order, and then stirred and mixed. The mixture is cooled, and a silica raw material is added thereto, and raw materials of SiO ₂ , Al ₂ O ₃ and M ₂ O (Na ₂ O + Adding a mixing molar ratio of K ₂ O), K ₂ O / M ₂ O, and H ₂ O to be 1.00: 0.5 to 0.6: 2.8 to 3.5: 0.2 to 0.3: 60 to 70; (ii) adding preformed crystal grains as seeds to the mixture, holding at 40 ° C. for 5 hours, and then crystallizing by heating at 40 ° C. to 90 ° C. over 10 hours with continuous stirring; (iii) washing the resulting crystal grains and then drying them; And (iv) an ion exchange step of increasing the content of Na ions by repeating the resulting crystal grains in 1 ~ 3 M NaCl aqueous solution for 1 to 3 times at 60 ° C. to 100 ° C. for 1 to 3 times. , LSX zeolite composed of 70 to 100 mol% of Na ions and 0 to 30 mol% of K ions in a cation with a Si / Al ratio of 1.1 or less and a crystal grain size of 2 μm or less while having a FAU structure Method for producing microparticles. The mixed molar ratio of SiO ₂ , Al ₂ O ₃ , M ₂ O (Na ₂ O + K ₂ O), K ₂ O / M ₂ O, and H ₂ O as raw material components is 1.00: 0.57: 3.25. : Method for producing LSX zeolite microparticles, characterized in that 0.25: 65. (delete) Prepared according to the method of claim 1, having a FAU structure, the Si / Al ratio is 1.1 or less, the crystal grain size is 2 ㎛ or less, 70 to 100 mol% Na ions in the cation, 0 to 30 K ions A detergent composition containing LSX zeolite particles composed of mol% as a builder for a detergent.

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