A molecular sieve polymer composite material and its preparation method and application

Abstract

The present invention relates to the technical field of molecular sieves, and discloses a molecular sieve polymer composite material and a preparation method and application thereof, wherein trimethylchlorosilane is used as a bridge to connect the molecular sieve and the polymer, and the polymer is coated on the surface of the molecular sieve. The molecular sieve obtained by the present invention has good hydrophobicity and good adsorption capacity for volatile organic compounds.

Description

Technical Field

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

[0002] Volatile organic compounds (VOCs) are a general term for volatile organic compounds with a melting point below room temperature and a boiling point between 50-260°C. They are widely distributed in the air, soil, and water. They are complex in type and seriously endanger the human nervous and immune systems, causing respiratory infections, neurological disorders, and other problems. They may also be carcinogenic, teratogenic, and mutagenic. In addition, most VOCs will cause secondary pollution, forming photochemical smog, etc., which seriously damages environmental quality and human health. At present, there are many methods for controlling VOCs, including adsorption, absorption, catalysis, and biological methods. Among them, the adsorption method is simple to operate, low in cost, and has high purification efficiency. It has become one of the most widely used treatment methods. The selection of adsorbent is crucial to adsorption performance.

[0003] Molecular sieves with unique pore structure and high specific surface area are ideal materials for adsorbing VOCs. However, their surface hydrophilicity leads to a decrease in the adsorption performance of VOCs in a humid environment. Optimizing the pore structure of the material and enhancing the hydrophobicity of the molecular sieve surface are the key to improving the adsorption performance of molecular sieves for humid VOCs gases. However, most hydrophobic modifications increase hydrophobicity at the expense of adsorption capacity and increase diffusion resistance; in addition, the effect of some hydrophobic modifications is not obvious, and the competitive adsorption of water vapor and VOCs is more serious. It can be seen that it is urgent to improve the adsorption capacity of molecular sieves for volatile organic compounds (VOCs). Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a molecular sieve polymer composite material and a preparation method and application thereof. The molecular sieve obtained by the present invention has good hydrophobicity and good adsorption capacity for volatile organic compounds.

[0005] The invention provides a molecular sieve macromolecular polymer composite material, in which trimethylchlorosilane is used as a bridge to connect the molecular sieve and the macromolecular polymer, and the macromolecular polymer is coated on the surface of the molecular sieve.

[0006] Furthermore, the high molecular polymer includes one or more of polyether block polyamide and polyether sulfone.

[0007] Furthermore, the polyether block polyamide is a polyether block polyamide with a weight average molecular weight of 2000-20000.

[0008] Furthermore, the polyethersulfone is a polyethersulfone with a weight average molecular weight of 2000-15000.

[0009] Furthermore, the high molecular polymer is polyether block polyamide.

[0010] The present invention also provides a method for preparing the molecular sieve polymer composite material, the method comprising:

[0011] The molecular sieve is dispersed in an organic solvent, and then trimethylchlorosilane is added to obtain a mixed solution, a solution containing a high molecular polymer is added, reacted, solid-liquid separated, washed, impurities removed, and the solid matter after impurities removal is dried to obtain a composite material.

[0012] Furthermore, the high molecular polymer includes one or more of polyether block polyamide and polyether sulfone.

[0013] Furthermore, the mass concentration of the molecular sieve in the organic solvent is 0.0125 g / mL-0.0625 g / mL.

[0014] Furthermore, in terms of mass, the mass ratio of the molecular sieve to trimethylchlorosilane is (5-25):1.

[0015] Furthermore, the ratio of the mixed solution to the solution containing the high molecular weight polymer is (1-2):(1-3) by volume.

[0016] Furthermore, the ratio of the molecular sieve to the high molecular polymer is (1-5):1 by mass.

[0017] Furthermore, the ratio of the molecular sieve to the high molecular polymer is 5:1 by mass.

[0018] Furthermore, the organic solvent includes one or more of methanol, ethanol, N-methylpyrrolidone, and N,N-dimethylformamide.

[0019] Furthermore, the reaction temperature is 60°C-120°C, and the reaction time is 3h-24h.

[0020] Furthermore, the method for preparing the solution containing the high molecular polymer includes: dispersing the high molecular polymer in an organic solvent.

[0021] Furthermore, the organic solvent includes one or more of methanol, ethanol, N-methylpyrrolidone, and N,N-dimethylformamide.

[0022] In order to promote sufficient dispersion of the high molecular polymer in the mixed solution, those skilled in the art may reflux and stir at 80° C.-100° C. for 15 min-40 min.

[0023] Furthermore, the washing method uses anhydrous ethanol for at least three times.

[0024] Furthermore, it should be understood by those skilled in the art that the purpose of impurity removal is to remove the solvent and unreacted molecular substances remaining in the pores other than the target solid after the reaction. As an example, the Soxhlet extraction method is used, and those skilled in the art can also adjust the impurity removal method according to actual conditions, as long as the purpose of impurity removal of the present invention can be achieved.

[0025] Furthermore, the drying temperature is 60°C-80°C, and the drying time is 12h-18h.

[0026] The invention also provides the use of the molecular sieve macromolecular polymer composite material in the adsorption of volatile organic compounds.

[0027] Furthermore, the volatile organic compounds include one or more of ketone volatile organic compounds and benzene volatile organic compounds.

[0028] The embodiments of the present invention have the following technical effects:

[0029] 1. In the composite material obtained by the present invention, trimethylchlorosilane connected to the molecular sieve improves the hydrophobicity of the molecular sieve, reduces the influence of water on the molecular sieve, and is beneficial to the molecular sieve's adsorption capacity for volatile organic substances; on this basis, trimethylchlorosilane serves as a connecting bridge to connect the molecular sieve and the high molecular polymer, and the high molecular polymer can improve the adsorption and diffusion capacity of the molecular sieve for volatile organic substances, and trimethylchlorosilane is not only conducive to the uniform coating of the high molecular polymer on the surface of the molecular sieve, but also improves the improvement effect of the high molecular polymer on the molecular sieve, thereby facilitating the capture of more volatile organic substances.

[0030] 2. In the present invention, the organic groups such as ether groups and amide groups contained in the high molecular polymer used can interact with the π bonds of benzene-based volatile organic compounds, which is beneficial to the adsorption of volatile organic compounds. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 It is a data diagram of toluene adsorption provided by the examples and comparative examples of the present invention.

[0033] Figure 2 It is the hydrophobicity of the materials provided in the embodiments and comparative examples of the present invention. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0035] In a first aspect, some embodiments of the present invention provide a molecular sieve-polymer composite material, in which trimethylchlorosilane serves as a bridge to connect the molecular sieve and the polymer, and the polymer is coated on the surface of the molecular sieve.

[0036] In some embodiments, the high molecular weight polymer includes one or more of polyether block polyamide and polyether sulfone.

[0037] In some embodiments, the polyether block polyamide is a polyether block polyamide having a weight average molecular weight of 2000-20000.

[0038] In some embodiments, the polyethersulfone is a polyethersulfone having a weight average molecular weight of 2000-15000.

[0039] In some embodiments, the high molecular weight polymer is polyether block polyamide.

[0040] In a second aspect, some embodiments of the present invention further provide a method for preparing the molecular sieve polymer composite material, the preparation method comprising:

[0041] The molecular sieve is dispersed in an organic solvent, and then trimethylchlorosilane is added to obtain a mixed solution, a solution containing a high molecular polymer is added, reacted, solid-liquid separated, washed, impurities removed, and the solid matter after impurities removal is dried to obtain a composite material.

[0042] In the method of the present invention, trimethylchlorosilane is connected to the high molecular polymer through hydrogen bonding, so that the high molecular polymer can be evenly coated on the surface of the molecular sieve; and trimethylchlorosilane reacts with the hydroxyl groups on the surface of the molecular sieve, so that the trimethylchlorosilane is successfully grafted to the surface of the molecular sieve, so that the trimethylchlorosilane not only serves as a connecting bridge between the molecular sieve and the high molecular polymer, but also enables the trimethylchlorosilane to improve the molecular sieve and the high molecular polymer, which is beneficial to improving the adsorption capacity of the composite material for ketone volatile organic compounds and benzene volatile organic compounds.

[0043] In some embodiments, the high molecular weight polymer includes one or more of polyether block polyamide and polyether sulfone.

[0044] In some embodiments, the mass concentration of the molecular sieve in the organic solvent is 0.0125 g / mL-0.0625 g / mL.

[0045] In some embodiments, the mass ratio of the molecular sieve to trimethylchlorosilane is (5-25):1.

[0046] In some embodiments, the ratio of the mixed solution to the solution containing the high molecular weight polymer is (1-2):(1-3) by volume.

[0047] In some embodiments, the ratio of the molecular sieve to the high molecular weight polymer is (1-5):1 by mass.

[0048] In some embodiments, the ratio of the molecular sieve to the high molecular weight polymer is 5:1 by mass.

[0049] In some embodiments, the organic solvent includes one or more of methanol, ethanol, N-methylpyrrolidone, and N,N-dimethylformamide.

[0050] In some embodiments, the reaction temperature is 60° C.-120° C., and the reaction time is 3 h-24 h.

[0051] In some embodiments, the method for preparing the solution containing the polymer includes: dispersing the polymer in an organic solvent.

[0052] In some embodiments, the organic solvent includes one or more of methanol, ethanol, N-methylpyrrolidone, and N,N-dimethylformamide.

[0053] In some embodiments, the washing method uses anhydrous ethanol for at least three times.

[0054] In some embodiments, the drying temperature is 60°C-80°C, and the drying time is 12-18h.

[0055] In a third aspect, some embodiments of the present invention also provide applications of molecular sieve polymer composite materials in the adsorption of volatile organic compounds.

[0056] In some embodiments, the volatile organic compounds include one or more of ketone volatile organic compounds and benzene volatile organic compounds.

[0057] The following is further described in conjunction with specific embodiments and comparative examples:

[0058] Embodiment 1:

[0059] (1) Weigh 0.1 g of trimethylsilyl chloride and add it to 40 mL of ethanol solution. After stirring for 10 min, add 0.5 g of Y molecular sieve and ultrasonicate for 30 min to obtain a mixed solution 1.

[0060] (2) Weigh 0.5 g of polyether block polyamide (weight average molecular weight: 10,000) and dissolve it in 40 mL of ethanol solution. Stir thoroughly to obtain a mixed solution 2.

[0061] (3) Mixed solution 1 and mixed solution 2 were mixed, refluxed and stirred at 80°C for 3 h, and naturally cooled to room temperature (25°C). The solid phase product was recovered by centrifugation, washed several times by centrifugation with ethanol, and extracted with methanol at 80°C for 12 h. Finally, it was vacuum dried at 60°C for 12 h to obtain the final sample.

[0062] Embodiment 2:

[0063] (1) Weigh 0.1 g of trimethylsilyl chloride and add it to 40 mL of ethanol solution. After stirring for 10 min, add 1.5 g of Y molecular sieve and ultrasonicate for 30 min to obtain a mixed solution 1.

[0064] (2) Weigh 0.5 g of polyether block polyamide (weight average molecular weight: 10,000) and dissolve it in 40 mL of ethanol solution. Stir thoroughly to obtain a mixed solution 2.

[0065] (3) Mixed solution 1 and mixed solution 2 were mixed, refluxed and stirred at 80°C for 3 h, and naturally cooled to room temperature. The solid phase product was recovered by centrifugation, washed several times by centrifugation with ethanol, and extracted with methanol at 80°C for 12 h. Finally, it was vacuum dried at 60°C for 12 h to obtain the final sample.

[0066] Embodiment 3:

[0067] (1) Weigh 0.1 g of trimethylsilyl chloride and add it to 40 mL of ethanol solution. After stirring for 10 min, add 2.5 g of Y molecular sieve and ultrasonicate for 30 min to obtain a mixed solution 1.

[0068] (2) Weigh 0.5 g of polyether block polyamide (weight average molecular weight: 10,000) and dissolve it in 40 mL of ethanol solution. Stir thoroughly to obtain a mixed solution 2.

[0069] (3) Mixed solution 1 and mixed solution 2, and reflux and stir at 80°C for 3 h. Cool naturally to room temperature, recover the solid phase product by centrifugation, wash it with ethanol by centrifugation for multiple times, and extract it with methanol at 80°C for 12 h. Finally, vacuum dry it at 60°C for 12 h to obtain the final sample.

[0070] Embodiment 4:

[0071] (1) Weigh 0.1 g of trimethylsilyl chloride and add it to 40 mL of ethanol solution. After stirring for 10 min, add 0.5 g of Y molecular sieve and ultrasonicate for 30 min to obtain a mixed solution 1.

[0072] (2) Weigh 0.5 g of polyethersulfone (weight average molecular weight: 10,000) and dissolve it in 40 mL of ethanol solution. Stir thoroughly to obtain a mixed solution 2.

[0073] (3) Mixed solution 1 and mixed solution 2 were mixed, refluxed and stirred at 80°C for 3 h, and naturally cooled to room temperature (25°C). The solid phase product was recovered by centrifugation, washed several times by centrifugation with ethanol, and extracted with methanol at 80°C for 12 h. Finally, it was vacuum dried at 60°C for 12 h to obtain the final sample.

[0074] Comparative Example 1:

[0075] (1) Weigh 0.5 g of Y molecular sieve and add it to 40 mL of ethanol solution. Stir and mix thoroughly to obtain solution 1.

[0076] (2) Weigh 0.5 g of polyether block polyamide (weight average molecular weight: 10,000) and dissolve it in 40 mL of ethanol solution. Stir thoroughly to obtain solution 2.

[0077] (3) Solution 1 and Solution 2 were mixed and refluxed at 80°C for 3 h. After cooling naturally to room temperature, the solid phase product was recovered by centrifugation, washed several times by centrifugation with ethanol, and extracted with methanol at 80°C for 12 h. Finally, it was vacuum dried at 60°C for 12 h to obtain the final sample.

[0078] Comparative Example 2:

[0079] (1) Weigh 0.1 g of trimethylsilyl chloride and add it to 40 mL of ethanol solution. After stirring for 10 min, add 0.5 g of Y molecular sieve and ultrasonicate for 30 min to obtain a mixed solution 1.

[0080] (2) Weigh 0.5 g of polyethylene glycol (weight average molecular weight: 10,000) and dissolve it in 40 mL of ethanol solution. Stir thoroughly to obtain a mixed solution 2.

[0081] (3) Mixed solution 1 and mixed solution 2 were mixed and refluxed at 80°C for 3 h. After naturally cooling to room temperature, the solid phase product was recovered by centrifugation, washed several times by centrifugation with ethanol, and extracted with methanol at 80°C for 12 h. Finally, it was vacuum dried at 60°C for 12 h to obtain the final sample.

[0082] Comparative Example 3:

[0083] (1) Weigh 0.1 g of phenyltriethoxysilane and add it to 40 mL of ethanol solution. After stirring for 10 min, add 0.5 g of Y molecular sieve and ultrasonicate for 30 min to obtain a mixed solution 1.

[0084] (2) Weigh 0.5 g of polyether block polyamide (weight average molecular weight: 10,000) and dissolve it in 40 mL of ethanol solution. Stir thoroughly to obtain a mixed solution 2.

[0085] (3) Mixed solution 1 and mixed solution 2 were mixed and refluxed at 80°C for 3 h. After naturally cooling to room temperature, the solid phase product was recovered by centrifugation, washed several times by centrifugation with ethanol, and extracted with methanol at 80°C for 12 h. Finally, it was vacuum dried at 60°C for 12 h to obtain the final sample.

[0086] Comparative Example 4: Y molecular sieve.

[0087] The products obtained from the examples and comparative examples were subjected to performance tests:

[0088] The composite material is used for the adsorption of toluene gas. 0.1g of the product is weighed and placed in a quartz tube reactor of the adsorption device. The product is pretreated before the adsorption begins, heated at 200°C for 2 hours and purged with nitrogen to remove the adsorbed water and other organic impurities in the material. After the pretreatment, it is cooled to room temperature for adsorption. The total adsorption flow rate is maintained at 100mL / min, and the initial concentration of toluene is 1100ppm. The outlet concentration is detected online by gas chromatography. When the outlet concentration reaches 95% of the initial concentration, the adsorption is considered saturated. The hydrophobic properties are tested by static water vapor adsorption experiments.

[0089] Results and analysis:

[0090] The molecular sieve is successfully modified by the method of the present invention. In the composite material of the present invention, trimethylchlorosilane can improve the hydrophobicity of the molecular sieve on the one hand, which is beneficial to reduce the influence of water on the adsorption capacity of the molecular sieve. On the other hand, trimethylchlorosilane can serve as a bridge to connect the molecular sieve and the high molecular polymer, so that the high molecular polymer can form a uniform coating layer on the surface of the molecular sieve, thereby improving the adsorption and diffusion capacity of volatile organic compounds of the composite material. Figure 1 and Figure 2 It can be found that the hydrophobicity and adsorption capacity of the composite material of the embodiment of the present invention are significantly better than those of the comparative example. It can be seen that the composite material obtained by the method of the present invention can improve the adsorption capacity of ketone volatile organic compounds and benzene volatile organic compounds.

[0091] In the present invention, trimethylchlorosilane is not only required to improve the hydrophobicity of the molecular sieve, but also to promote uniform coating of the polymer. Further comparison of Examples 1 to 4 and Comparative Example 1 revealed that when trimethylchlorosilane was lost in the composite material, the adsorption capacity of the composite material for toluene was significantly reduced, and was even worse than that of Comparative Example 4 which was not improved. It is speculated that this may be because the polymer layer did not form a uniform coating layer on the surface of the molecular sieve, and the hydrophobicity of the molecular sieve was not improved, resulting in a significant reduction in the adsorption capacity of Comparative Example 1.

[0092] On this basis, the coordination between trimethylchlorosilane and polymer was further studied, and Example 1, Example 4 and Comparative Examples 2-3 were further studied. It was found that the toluene adsorption capacity and hydrophobicity of the composite materials of Example 1 and Example 4 were significantly better than those of Comparative Examples 2-3. First, the organic groups such as ether groups and amides contained in the polymer of the present invention can interact with the π bonds of benzene-based volatile organic compounds, which is beneficial to the adsorption of volatile organic compounds; second, the trimethylchlorosilane in the present invention can produce hydrogen bonds with the polymer containing ether groups and amide organic groups, thereby achieving uniform dispersion of the polymer; third, due to the difference between the matching effects between trimethylchlorosilane and the polymer, the adsorption capacity and hydrophobicity of the final composite material are different, so Example 1 is better than Example 4, and significantly better than Comparative Examples 2-3. Therefore, in the present invention, it is further preferred that the polymer is a polyether block polyamide.

[0093] Finally, the coating thickness of the polymer was further studied. When the amount of the polymer is too much, the coating layer will be thicker, and the hydrophobicity and adsorption and diffusion capacity of the composite material will decrease; when the amount of the polymer is too little, the coating layer will be thinner, which may cause uneven coating. Therefore, in the present invention, the ratio of molecular sieve to polymer is (1-5):1. Considering the hydrophobicity and adsorption capacity, it is further preferred that the ratio of molecular sieve to polymer is 5:1.

[0094] In summary, the composite material obtained by the present invention has good adsorption capacity for ketone volatile organic compounds and benzene volatile organic compounds.

[0095] It should be noted that the terms used in the present invention are only for describing specific embodiments, rather than limiting the scope of the present application. As shown in the present specification, unless the context clearly indicates an exception, the words "one", "a", "a kind of" and / or "the" do not specifically refer to the singular, but may also include the plural. The terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method or device. In the absence of more restrictions, the elements defined by the sentence "include one..." do not exclude the presence of other identical elements in the process, method or device including the elements.

[0096] It should also be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0097] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention.

Claims

1. A molecular sieve polymer composite material, characterized in that: In the composite material, trimethylchlorosilane serves as a bridge to connect the molecular sieve and the high molecular polymer, and the high molecular polymer is coated on the surface of the molecular sieve; The high molecular polymer is polyether block polyamide; The preparation method of the composite material comprises: The molecular sieve is dispersed in an organic solvent, and then trimethylsilyl chloride is added to obtain a mixed solution, a solution containing a high molecular weight polymer is added, reacted, solid-liquid separated, washed, impurities removed, and the solid matter after impurities removal is dried to obtain a composite material; In terms of mass, the mass ratio of the molecular sieve to trimethylchlorosilane is (5-25):

1.

2. A method for preparing the molecular sieve polymer composite material according to claim 1, characterized in that: The preparation method comprises: The molecular sieve is dispersed in an organic solvent, and then trimethylchlorosilane is added to obtain a mixed solution, a solution containing a high molecular polymer is added, reacted, solid-liquid separated, washed, impurities removed, and the solid matter after impurities removal is dried to obtain a composite material.

3. The preparation method according to claim 2, characterized in that: The mass concentration of the molecular sieve in the organic solvent is 0.0125 g / mL-0.0625 g / mL; In terms of mass, the mass ratio of the molecular sieve to trimethylchlorosilane is (5-25):1; The volume ratio of the mixed solution to the solution containing the high molecular weight polymer is (1-2):(1-3).

4. The preparation method according to claim 2, characterized in that: In terms of mass, the ratio of the molecular sieve to the high molecular polymer is (1-5):

1.

5. The preparation method according to claim 2, characterized in that: The reaction temperature is 60-120° C., and the reaction time is 3-24 hours.

6. The preparation method according to claim 2, characterized in that: The organic solvent includes one or more of methanol, ethanol, N-methylpyrrolidone, and N,N-dimethylformamide.

7. Use of the molecular sieve polymer composite material according to claim 1 or the molecular sieve polymer composite material obtained by the preparation method according to any one of claims 2 to 6 in adsorbing volatile organic compounds.

8. The use according to claim 7, characterized in that: The volatile organic compounds include one or more of ketone volatile organic compounds and benzene volatile organic compounds.

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