A spherical molecular sieve and its preparation method and application

Abstract

The present invention relates to the field of molecular sieve technology, and more particularly to a spherical molecular sieve and its preparation method and application, the spherical molecular sieve is based on molecular sieve raw powder as base material, and is mixed according to the mass ratio of molecular sieve raw powder: binder: metal compound of 50-80:15-50:0.5-10. The present invention has the advantage that the spherical molecular sieve is based on molecular sieve as the main active component, and the binder has a porous structure, and the spherical molecular sieve has a larger specific surface area, has higher adsorption and ion exchange capacity, and the hardness of the molecular sieve is moderate, and tooth enamel will not be hurt when used as a toothpaste abrasive, and clothing fiber will not be hurt when used as a detergent additive. The spherical molecular sieve provided by the present invention also includes a metal compound component, which not only plays a whitening effect, but also has a certain bactericidal function. When the spherical molecular sieve provided by the present invention is used as a moisturizing agent, it can effectively reduce water volatilization and improve the moisturizing effect.

Description

Technical Field

[0001] The present invention relates to the technical field of molecular sieves, and in particular to a spherical molecular sieve and a preparation method and application thereof. Background Art

[0002] Molecular sieve, also known as zeolite, is an inorganic aluminosilicate material with excellent performance and wide application. Its regular sub-nanometer microporous structure, large specific surface area and excellent adsorption performance make it widely used in petrochemical, coal chemical, industrial adsorption separation, environmental protection, animal feed, medical health and daily chemicals. Especially in the field of daily chemicals, molecular sieves have shown good application prospects as toothpaste abrasive additives, detergent additives and moisturizers. However, existing molecular sieve products often have problems such as irregular shape, uneven particle size distribution and limited adsorption performance, which restricts its further application in the field of daily chemicals. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a spherical molecular sieve and a preparation method and application thereof. The present invention obtains a spherical molecular sieve with regular shape, uniform particle size distribution and excellent adsorption performance through a specific preparation process, which is suitable for various application scenarios in the field of daily chemicals.

[0004] The present invention is achieved through the following technical solutions: On the one hand, a spherical molecular sieve is provided, which is based on molecular sieve raw powder and is mixed according to the mass ratio of molecular sieve raw powder: binder: metal compound of 50-80:15-50:0.5-10.

[0005] Through the above technical scheme, the spherical molecular sieve provided by the present invention comprises three components: molecular sieve raw powder, binder and metal compound. The three components play different roles. The molecular sieve raw powder has a large specific surface area, which mainly plays a high adsorption and ion exchange role; the binder mainly plays a bonding role, and the molecular sieve raw powder and the metal compound that do not have bonding properties are bonded into spherical particles, so that they have suitable strength; the metal compound mainly plays a whitening and sterilization role. The inventor of the present invention found in the experiment that if the molecular sieve raw powder content is too low (such as <30%), the molecular sieve raw powder can not play a significant role; if the molecular sieve raw powder content is too high (such as >80%), the spherical molecular sieve raw powder has poor strength due to the low content of the binder, and cannot effectively play a role of friction; if only the first metal compound is used, because it does not have bonding properties with the molecular sieve raw powder, it will also cause the spherical molecular sieve to have poor strength; and if only the second metal compound is used, although the strength of the spherical molecular sieve can be guaranteed, it will cause the molecular sieve pores to be blocked and weaken the role of the molecular sieve. Therefore, the amounts of molecular sieve powder, binder, first metal compound and second metal compound need to be balanced with each other to take into account the functions and advantages of each component.

[0006] A method for preparing the spherical molecular sieve is also provided, comprising the following steps:

[0007] Step S1, introducing metal ions for the first time: mixing the molecular sieve raw powder, the binder and the metal compound according to the above mass ratio;

[0008] Step S2, ball milling; forming and granulating the obtained mixture into spherical particles with a particle size of 0.10-0.50 mm;

[0009] Step S3, drying: drying and high temperature treatment of the obtained spherical particles;

[0010] Step S4, secondary introduction of metal ions; contacting the obtained spherical particles with a solution containing a second metal compound; wherein the solution containing the second metal compound is an acid solution with a mass concentration of 5-15%;

[0011] Step S5, finished product: removing the solvent from the obtained spherical particles, and drying and high-temperature treatment are performed to obtain the finished product.

[0012] Through the above technical scheme, the spherical molecular sieve provided by the present invention has molecular sieve as the main active component, and the binder also has a porous structure. The spherical molecular sieve has a large specific surface area, a high adsorption and ion exchange capacity, and the molecular sieve has a moderate hardness. It will not damage tooth enamel when used as a toothpaste abrasive, and will not damage clothing fibers when used as a detergent additive. The spherical molecular sieve provided by the present invention also contains a metal compound component, which can play a whitening role and also has a certain bactericidal function. When the spherical molecular sieve provided by the present invention is used as a moisturizer, it can effectively reduce water volatilization and improve the moisturizing effect.

[0013] Furthermore, in step S1, the molecular sieve raw powder is selected from synthetic molecular sieves of structures such as LTA, FAU, MOR, MFI, HEU, FER, BEA, MRE, TON, MTT, etc.; or at least one of natural molecular sieves such as clinoptilolite, ferrierite, chbazite, mordenite, etc.

[0014] Furthermore, in step S1, the binder is selected from any one or more of a solid binder and a liquid binder; the solid binder is selected from at least one of pseudo-boehmite, ρ-alumina, kaolin, and attapulgite; the liquid binder is selected from at least one of silica sol, alumina sol, and silica-alumina sol.

[0015] Further, in step S1, the metal compound is selected from at least one of titanium oxide (TiO2), zinc oxide (ZnO), zinc citrate, zinc lactate, zinc acetate, magnesium lactate, magnesium acetate, magnesium oxide (MgO), and strontium chloride (SrCl2).

[0016] Furthermore, in step S2, the molding granulation is any one of spray granulation or ball molding granulation.

[0017] Furthermore, in step S3 / S5, the drying treatment temperature is 50-150°C, and the treatment time is 0.5-24h; the high temperature treatment temperature is 200-550°C, and the treatment time is 0.5-12h.

[0018] Furthermore, in step S4, the second metal compound is selected from at least one of organic titanium ester, inorganic titanium tetrachloride, zinc citrate, zinc lactate, zinc acetate, magnesium lactate, magnesium acetate, magnesium chloride, and strontium chloride.

[0019] Furthermore, in step S4, the contact is selected from at least one of normal pressure liquid-solid phase contact, vacuum liquid-solid phase contact / equal volume immersion.

[0020] Finally, an application of a spherical molecular sieve is provided, the spherical molecular sieve is based on the above-mentioned spherical molecular sieve, or is prepared by the above-mentioned spherical molecular sieve preparation method, the spherical molecular sieve is suitable for the field of daily chemicals, and is selected as any one of a toothpaste abrasive agent, a washing aid, and a moisturizer; and the addition amount of the spherical molecular sieve is ≥0.5%. The spherical molecular sieve provided by the present invention is used as a toothpaste abrasive agent, which can have the effect of whitening and stain removal; as a detergent aid, it can improve the decontamination efficiency; it can also be used as a moisturizer in various scenarios, etc.

[0021] Beneficial effects:

[0022] The present invention uses a specific preparation process to obtain a spherical molecular sieve with regular shape, uniform particle size distribution and excellent adsorption performance, which is suitable for various application scenarios in the field of daily chemicals; and the preparation method of the present invention has a simple process and good repeatability.

[0023] The present invention is a spherical molecular sieve with molecular sieve as the main active component, and the binder has a porous structure. The spherical molecular sieve has a large specific surface area, a high adsorption and ion exchange capacity, and the molecular sieve has a moderate hardness. It will not damage tooth enamel when used as a toothpaste abrasive, and will not damage clothing fibers when used as a detergent additive. The spherical molecular sieve provided by the present invention also contains a metal compound component, which not only plays a whitening role, but also has a certain bactericidal function. When the spherical molecular sieve provided by the present invention is used as a moisturizer, it can effectively reduce water volatilization and improve the moisturizing effect.

[0024] The present invention can significantly improve the catalytic activity of the molecular sieve by introducing the second metal compound, which is specifically reflected in the following aspects:

[0025] The metal ions are distributed inside and outside the molecular sieve framework to form active sites, making it easier for reactants to approach and react. Different metal ions have different selectivities for different chemical reactions. By introducing a specific second metal compound, not only can the catalytic selectivity of the molecular sieve be adjusted to make it more suitable for a specific chemical reaction. Certain metal ions can preferentially catalyze a certain type of reaction and inhibit other types of reactions. The introduction of the second metal compound can improve the thermal stability and chemical stability of the molecular sieve. The metal ions form chemical bonds with the oxygen atoms in the molecular sieve framework, enhancing the stability of the framework structure. This allows the molecular sieve to maintain its catalytic performance in high temperature, high pressure or corrosive environments. The second metal compound can change the surface properties of the molecular sieve, such as surface acidity and alkalinity, hydrophilicity and hydrophobicity, etc. Changes in these properties not only affect the adsorption and desorption behavior of the reactants on the molecular sieve surface, but also affect the rate and efficiency of the catalytic reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A macroscopic photograph of the spherical molecular sieve sample prepared in Example 2 of the present invention is shown;

[0027] Figure 2 This is a partially enlarged photograph of the spherical molecular sieve sample prepared in Example 2 of the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. The experimental methods without specific conditions in the following examples are usually carried out under conventional conditions or according to the conditions recommended by the manufacturer. Unless otherwise specified, all percentages, ratios, proportions or parts are by weight.

[0030] Unless otherwise specified, the reagents and raw materials used in the examples and comparative examples of the present invention can be obtained through commercial channels.

[0031] Example 1

[0032] A method for preparing a spherical molecular sieve comprises the following steps:

[0033] Step S1, introducing metal ions for the first time; mixing 4A molecular sieve, ρ-alumina and TiO2 in a dry weight ratio of 61:35:4;

[0034] Step S2, ball milling; the obtained mixture is granulated by rolling ball to form spherical particles with a particle size of 0.2-0.40 mm;

[0035] Step S3, drying; drying the obtained spherical particles at 100° C. for 4 hours, and then high-temperature treating at 350° C. for 2 hours;

[0036] Step S4, secondary introduction of metal ions; placing the obtained spherical particles in contact with a nitric acid solution containing 5% titanium tetrachloride at room temperature for 4 hours;

[0037] Step S5, finished product; the solvent in the obtained spherical particles is removed by suction filtration, and then dried at 100° C. for 4 hours and high-temperature treated at 450° C. for 2 hours to obtain the finished product.

[0038] Example 2

[0039] A method for preparing a spherical molecular sieve comprises the following steps:

[0040] Step S1, introducing metal ions for the first time; mixing 4A molecular sieve, ρ-alumina and TiO2 in a dry weight ratio of 75:21:4;

[0041] Step S2, ball milling; the obtained mixture is granulated by rolling ball to form spherical particles with a particle size of 0.2-0.40 mm;

[0042] Step S3, drying; drying the obtained spherical particles at 100° C. for 4 hours, and then high-temperature treating at 350° C. for 2 hours;

[0043] Step S4, secondary introduction of metal ions; placing the obtained spherical particles in contact with a nitric acid solution containing 6% titanium tetrachloride at room temperature for 4 hours;

[0044] Step S5, finished product; the solvent in the obtained spherical particles is removed by suction filtration, and then dried at 100° C. for 4 hours and high-temperature treated at 450° C. for 2 hours to obtain the finished product.

[0045] Example 3

[0046] A method for preparing a spherical molecular sieve comprises the following steps:

[0047] Step S1, introducing metal ions for the first time; mixing 4A molecular sieve, ρ-alumina and TiO2 in a dry weight ratio of 75:20:5;

[0048] Step S2, ball milling; the obtained mixture is granulated by rolling ball to form spherical particles with a particle size of 0.2-0.40 mm;

[0049] Step S3, drying; drying the obtained spherical particles at 100° C. for 4 hours, and then high-temperature treating at 350° C. for 2 hours;

[0050] Step S4, secondary introduction of metal ions; placing the obtained spherical particles in contact with an acetic acid solution having a zinc acetate content of 15% at room temperature for 4 hours;

[0051] Step S5, finished product; the solvent in the obtained spherical particles is removed by suction filtration, and then dried at 150° C. for 24 hours and high-temperature treated at 550° C. for 12 hours to obtain the finished product.

[0052] Example 4

[0053] A method for preparing a spherical molecular sieve comprises the following steps:

[0054] Step S1, introducing metal ions for the first time; mixing 4A molecular sieve, acidic silica sol and TiO2 in a dry weight ratio of oxides of 74.5:22:3.5;

[0055] Step S2, ball milling; spray granulating the obtained mixture into spherical particles with a particle size of 0.2-0.40 mm;

[0056] Step S3, drying; drying the obtained spherical particles at 100° C. for 4 hours, and then high-temperature treating at 350° C. for 2 hours;

[0057] Step S4, secondary introduction of metal ions; placing the obtained spherical particles in contact with a nitric acid solution containing 6% titanium tetrachloride at room temperature for 4 hours;

[0058] Step S5, finished product; the solvent in the obtained spherical particles is removed by suction filtration, and then dried at 100° C. for 4 hours and high-temperature treated at 450° C. for 2 hours to obtain the finished product.

[0059] Example 5

[0060] A method for preparing a spherical molecular sieve comprises the following steps:

[0061] Step S1, introducing metal ions for the first time; mixing natural mordenite, acidic silica sol and TiO2 in a dry weight ratio of oxides of 74.5:22:3.5;

[0062] Step S2, ball milling; spray granulating the obtained mixture into spherical particles with a particle size of 0.2-0.40 mm;

[0063] Step S3, drying; drying the obtained spherical particles at 100° C. for 4 hours, and then high-temperature treating at 350° C. for 2 hours;

[0064] Step S4, secondary introduction of metal ions; placing the obtained spherical particles in contact with an acetic acid solution containing 8% magnesium acetate at room temperature for 4 hours;

[0065] Step S5, finished product; the solvent in the obtained spherical particles is removed by suction filtration, and then dried at 100° C. for 4 hours and high-temperature treated at 450° C. for 2 hours to obtain the finished product.

[0066] Example 6

[0067] A method for preparing a spherical molecular sieve comprises the following steps:

[0068] Step S1, introducing metal ions for the first time; mixing 4A molecular sieve, acidic silica sol and TiO2 in a dry weight ratio of 50:42:8 on an oxide basis;

[0069] Step S2, ball milling; spray granulating the obtained mixture into spherical particles with a particle size of 0.10-0.30 mm;

[0070] Step S3, drying; drying the obtained spherical particles at 50° C. for 0.5 h, and then high-temperature treating at 200° C. for 0.5 h;

[0071] Step S4, secondary introduction of metal ions; placing the obtained spherical particles in contact with a nitric acid solution containing 6% titanium tetrachloride at room temperature for 4 hours;

[0072] Step S5, finished product; the solvent in the obtained spherical particles is removed by suction filtration, and then dried at 50° C. for 24 hours and high-temperature treated at 550° C. for 0.5 hours to obtain the finished product.

[0073] Comparative Example 1

[0074] A method for preparing a spherical molecular sieve comprises the following steps:

[0075] Step S1, introducing metal ions for the first time; mixing 4A molecular sieve, ρ-alumina and TiO2 in a dry weight ratio of 31:65:4;

[0076] Step S2, ball milling; the obtained mixture is granulated by rolling ball to form spherical particles with a particle size of 0.2-0.40 mm;

[0077] Step S3, drying; drying the obtained spherical particles at 100° C. for 4 hours, and then high-temperature treating at 350° C. for 2 hours;

[0078] Step S4, secondary introduction of metal ions; placing the obtained spherical particles in contact with a nitric acid solution containing 6% titanium tetrachloride at room temperature for 4 hours;

[0079] Step S5, finished product; the solvent in the obtained spherical particles is removed by suction filtration, and then dried at 100° C. for 4 hours and high-temperature treated at 450° C. for 2 hours to obtain the finished product.

[0080] Comparative Example 2

[0081] A method for preparing a spherical molecular sieve comprises the following steps:

[0082] Step S1, introducing metal ions for the first time; mixing 4A molecular sieve, ρ-alumina and TiO2 in a dry weight ratio of 82:15:3;

[0083] Step S2, ball milling; the obtained mixture is granulated by rolling ball to form spherical particles with a particle size of 0.2-0.40 mm;

[0084] Step S3, drying; drying the obtained spherical particles at 100° C. for 4 hours, and then high-temperature treating at 350° C. for 2 hours;

[0085] Step S4, secondary introduction of metal ions; placing the obtained spherical particles in contact with a nitric acid solution containing 6% titanium tetrachloride at room temperature for 4 hours;

[0086] Step S5, finished product; the solvent in the obtained spherical particles is removed by suction filtration, and then dried at 100° C. for 4 hours and high-temperature treated at 450° C. for 2 hours to obtain the finished product.

[0087] Comparative Example 3

[0088] A method for preparing a spherical molecular sieve comprises the following steps:

[0089] Step S1, introducing metal ions for the first time; mixing 4A molecular sieve, ρ-alumina and TiO2 in a dry weight ratio of 72:20:8;

[0090] Step S2, ball milling; the obtained mixture is granulated by rolling ball to form spherical particles with a particle size of 0.2-0.40 mm;

[0091] Step S3, drying; drying the obtained spherical particles at 100° C. for 4 h, and then high-temperature treating at 350° C. for 2 h.

[0092] Comparative Example 4

[0093] A method for preparing a spherical molecular sieve comprises the following steps:

[0094] Step S1, introducing metal ions for the first time; mixing 4A molecular sieve and ρ-alumina at a dry weight ratio of 75:21;

[0095] Step S2, ball milling; the obtained mixture is granulated by rolling ball to form spherical particles with a particle size of 0.2-0.40 mm;

[0096] Step S3, drying; drying the obtained spherical particles at 100° C. for 4 hours, and then high-temperature treating at 350° C. for 2 hours;

[0097] Step S4, secondary introduction of metal ions; placing the obtained spherical particles in contact with a nitric acid solution containing 12% titanium tetrachloride at room temperature for 4 hours;

[0098] Step S5, finished product; the solvent in the obtained spherical particles is removed by suction filtration, and then dried at 100° C. for 4 hours and high-temperature treated at 450° C. for 2 hours to obtain the finished product.

[0099] Effect Example

[0100] The elemental composition of the molecular sieves of Examples 1-6 and Comparative Examples 1-4 was analyzed by X-ray fluorescence spectrometry (XRF). The analysis data are shown in Table 1. The crushing strength, specific surface area and pore volume analysis data are shown in Table 2.

[0101] The spherical molecular sieve sample prepared in Example 2 is shown in Figure 1 and Figure 2 .

[0102] Table 1

[0103]

[0104] Table 2

[0105]

[0106] From the analysis of Table 1 and Table 2, it can be seen that when the molecular sieve content is too low (Comparative Example 1), the crushing strength of the spherical molecular sieve is too high (low crushing rate), and the specific surface area and pore volume are both small; when the molecular sieve content is too high (Comparative Example 2), the binder ratio is too low, which makes it difficult to form, and the amount of acid used for forming needs to be increased, but the crushing strength of the spherical molecular sieve is low (high crushing rate), which does not meet the use requirements; when only the first metal compound is used (Comparative Example 3), the crushing strength of the spherical molecular sieve still does not meet the use requirements; and when only the second metal compound is used (Comparative Example 4), although the crushing strength meets the requirements, the specific surface area and pore volume are significantly reduced, which affects the function of the molecular sieve.

[0107] When the best embodiment of the present invention (Examples 1-6) is used, the effects of the molecular sieve and the metal compound can be taken into account, and the spherical molecular sieve obtained has moderate crushing strength, high specific surface area and pore volume. The excellent performance of the spherical molecular sieve will be reflected in the efficacy evaluation.

[0108] The evaluation method of spherical molecular sieve as a toothpaste abrasive is as follows:

[0109] Taking a commercially available toothpaste as a benchmark, the spherical molecular sieve prepared in Example 2 was evenly mixed with a commercially available toothpaste at a weight ratio of 0.5% and 8%. Then, referring to the method of T / COCIA7-2020, the teeth whitening performance was evaluated using a bovine tooth module, and the results are shown in Tables 3 and 4.

[0110] Table 3

[0111]

[0112] Table 4

[0113]

[0114] From the results in Table 3 and Table 4, it can be seen that after adding the spherical molecular sieve prepared according to the best embodiment of the present invention (Example 2) into toothpaste, the whitening performance is significantly improved compared with the reference toothpaste. Obviously, such improvement is brought about by the excellent performance of the spherical molecular sieve prepared by the present invention.

[0115] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a spherical molecular sieve, characterized in that: The specific preparation steps of this method are as follows: Step S1, introducing metal ions for the first time; mixing molecular sieve raw powder: binder: metal compound in a mass ratio of 50-80:15-50:0.5-5; Step S2, ball milling; forming and granulating the obtained mixture into spherical particles with a particle size of 0.10-0.50 mm; Step S3, drying: drying and high temperature treatment of the obtained spherical particles; Step S4, secondary introduction of metal ions; contacting the obtained spherical particles with a solution containing a second metal compound; wherein the solution containing the second metal compound is an acid solution with a mass concentration of 5-15%; Step S5, finished product; removing the solvent from the obtained spherical particles, and drying and high-temperature treatment to obtain; In step S1, the metal compound is selected from at least one of titanium oxide TiO2, zinc oxide ZnO, zinc citrate, zinc lactate, zinc acetate, magnesium lactate, magnesium acetate, and magnesium oxide MgO; In step S4, the second metal compound is selected from at least one of organic titanium ester, inorganic titanium tetrachloride, zinc citrate, zinc lactate, zinc acetate, magnesium lactate, magnesium acetate, and magnesium chloride; In step S3 and step S5, the high temperature treatment temperature is 200-550° C., and the treatment time is 0.5-12 hours.

2. The method for preparing a spherical molecular sieve according to claim 1, characterized in that: In step S1, the molecular sieve raw powder is selected from at least one of LTA, FAU, MOR, MFI, HEU, FER, BEA, MRE, TON, MTT, clinoptilolite, ferrierite, zeolite, chabazite, and mordenite.

3. The method for preparing a spherical molecular sieve according to claim 1, characterized in that: In step S1, the binder is selected from any one or more of a solid binder and a liquid binder; the solid binder is selected from at least one of pseudo-boehmite, ρ-alumina, kaolin, and attapulgite; the liquid binder is selected from at least one of silica sol, alumina sol, and silica-alumina sol.

4. The method for preparing a spherical molecular sieve according to claim 1, characterized in that: In step S2, the molding granulation is any one of spray granulation or ball molding granulation.

5. The method for preparing a spherical molecular sieve according to claim 1, characterized in that: In step S3 and step S5, the drying treatment temperature is 50-150° C., and the treatment time is 0.5-24 h.

6. The method for preparing a spherical molecular sieve according to claim 1, characterized in that: In step S4, the contact is selected from at least one of normal pressure liquid-solid phase contact, vacuum liquid-solid phase contact or equal volume immersion.

7. An application of a spherical molecular sieve, wherein the spherical molecular sieve is prepared by the preparation method of the spherical molecular sieve according to any one of claims 2 to 6, characterized in that: The spherical molecular sieve is suitable for the field of daily chemicals and can be selected as any one of a toothpaste abrasive additive and a washing additive; and the addition amount of the spherical molecular sieve is ≥0.5%.

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