Method for producing siloxane compound adsorbent, siloxane compound adsorbent, precision instruments, and paints

Abstract

To provide a siloxane compound adsorbent that has high adsorption power to a siloxane compound and also has an adsorption holding ability at high temperatures.SOLUTION: A method for producing a siloxane compound adsorbent includes the steps of: mixing mesoporous silica or activated carbon as a substrate, a binder having a hydroxy group, and a solvent to give a mixture; molding the mixture to give a molded article; and drying the molded article.SELECTED DRAWING: Figure 1A

Description

[Technical Field] 【0001】 This disclosure relates to a method for producing a siloxane compound adsorbent, a siloxane compound adsorbent, precision instruments, and paints. [Background technology] 【0002】 Silicone-based materials are used in various fields such as spacecraft, aircraft, automobiles, and cleanrooms due to their weather resistance, heat resistance, UV resistance, radiation resistance, and chemical resistance. However, siloxane compounds are released as outgassing from silicone-based materials, causing contamination of equipment with siloxane compounds, particularly in the spacecraft, automotive, and semiconductor manufacturing fields. In the biogas field, siloxane compounds can cause filter clogging, and in oil fan heaters, the accumulation of siloxane compounds can lead to ignition failures and premature extinguishing of the flame. 【0003】 Siloxane compounds are difficult to remove once they adhere, and exposure to heat or ultraviolet light causes polymerization reactions between siloxane molecules, making their adhesion even stronger. To address the generation of siloxane compounds, methods for reducing and removing them using adsorbents and filters have been developed and put into practical use. 【0004】 For example, Patent Document 1 discloses "an LP gas sensor filter characterized by mixing silica having a high specific surface area, such as a silica-based mesoporous material, with a dilution material such as activated clay, thereby improving the siloxane gas adsorption performance with the silica-based mesoporous material" (see Claim 1 of Patent Document 1). 【0005】 Non-patent documents 1 and 2 disclose adsorbents and methods for removing siloxane compounds from biogas. 【0006】 Non-Patent Document 3 discloses a technique for removing siloxane compounds adhering to the surface of precision equipment, which involves heating (baking) the precision equipment itself to remove the siloxane compounds. It is stated that, using the technique described in Non-Patent Document 3, the amount of outgassing (including gases other than siloxane compounds) from the entire set of components could be reduced to below a set baking completion threshold through baking. [Prior art documents] [Patent Documents] 【0007】 [Patent Document 1] Japanese Patent Publication No. 2010-164317 [Non-patent literature] 【0008】 [Non-Patent Document 1] G.Wang, et al., Critical Reviews in Environmental Science and Technology, 2019, Vol. 29, No. 4, 2257-2313 [Non-Patent Document 2] M. Shen, et al, Environmental Science and Pollution Research (2018) 25:30847-30862 [Non-Patent Document 3] Tamura, Tomonori et al., Bulletin of the National Astronomical Observatory of Japan, Vol. 8, 21-28 (2005) [Overview of the project] [Problems that the invention aims to solve] 【0009】 In the technology described in Patent Document 1, during the formation stage of the filter for the LP gas sensor, it is necessary to hold the activated clay powder and silica-based mesoporous powder in a nonwoven fabric or a binder such as resin. However, since the thermal stability of the nonwoven fabric or resin itself is not considered, it cannot be used under high-temperature conditions, and there is room for improvement. 【0010】 The methods disclosed in Non-Patent Documents 1 and 2 are methods for removing siloxane compounds from gas flow, and do not disclose methods for preventing the adhesion of siloxane compounds present in the environment to precision instruments. 【0011】 In Non-Patent Document 3, it is difficult to completely remove the adhered siloxane compounds. Due to the polymerization reaction of siloxane molecules caused by heating during baking, the adhesion becomes stronger, resulting in a problem that the performance of precision instruments decreases significantly more than expected. 【0012】 Therefore, the present disclosure provides a siloxane compound adsorbent having a high adsorption capacity for siloxane compounds and an adsorption retention capacity at high temperatures. 【Means for Solving the Problems】 【0013】 In order to solve the above problems, the method for manufacturing a siloxane compound adsorbent of the present disclosure includes mixing mesoporous silica or activated carbon as a base material, a binder having a hydroxy group, and a solvent to obtain a mixture, molding the mixture to obtain a molded product, and drying the molded product. 【0014】 Further features related to the present disclosure will become apparent from the description of this specification and the accompanying drawings. Also, aspects of the present disclosure are achieved and realized by elements and combinations of various elements and the aspects of the following detailed description and the appended claims. The description of this specification is merely a typical example and does not limit the scope of the claims or application examples of the present disclosure in any sense. 【Effects of the Invention】 【0015】 According to the technology of the present disclosure, it is possible to provide a siloxane compound adsorbent having a high adsorption capacity for siloxane compounds and an adsorption retention capacity at high temperatures. Other problems, configurations, and effects than those described above will be clarified by the description of the following embodiments. [Brief explanation of the drawing] 【0016】 [Figure 1A] This shows the infrared spectra of the adsorbent and mesoporous silica raw material according to Example 1. [Figure 1B] This is an enlarged infrared spectrum of region 1 in Figure 1A. [Figure 1C] This is an enlarged infrared spectrum of region 2 in Figure 1A. [Figure 1D] This graph shows the relationship between the adsorption performance of siloxane compounds in the adsorbent according to Example 1 and temperature. [Figure 2] This graph shows the relationship between the adsorption performance of siloxane compounds in the adsorbent according to Example 2 and temperature. [Figure 3] This graph shows the relationship between the adsorption performance of siloxane compounds in the adsorbent according to Example 3 and temperature. [Figure 4] This graph shows the relationship between the adsorption performance of siloxane compounds in the adsorbent according to Example 4 and temperature. [Figure 5] This graph shows the relationship between the adsorption performance of siloxane compounds in the adsorbent according to Example 5 and temperature. [Figure 6] This graph shows the relationship between the adsorption performance of siloxane compounds in the adsorbent according to Example 6 and temperature. [Figure 7] This graph shows the relationship between the adsorption performance of siloxane compounds in the adsorbent related to Comparative Example 1 and temperature. [Figure 8] This graph shows the relationship between the adsorption performance of siloxane compounds in the adsorbent of Comparative Example 2 and temperature. [Figure 9] This graph shows the relationship between the adsorption performance of siloxane compounds in the adsorbent according to Example 7 and temperature. [Figure 10] This graph shows the relationship between the adsorption performance of siloxane compounds in the adsorbent according to Example 8 and temperature. [Figure 11] This graph shows the relationship between the adsorption performance of siloxane compounds in the adsorbent according to Example 9 and temperature. [Figure 12] This graph shows the relationship between the adsorption performance of siloxane compounds in the adsorbent according to Example 10 and temperature. [Figure 13] This graph shows the relationship between the adsorption performance of siloxane compounds in the adsorbent according to Example 11 and temperature. [Figure 14] This graph shows the relationship between the adsorption performance of siloxane compounds in the adsorbent according to Example 12 and temperature. [Modes for carrying out the invention] 【0017】 [First Embodiment] <Method for producing siloxane compound adsorbent> The method for producing the siloxane compound adsorbent according to this embodiment includes mixing mesoporous silica or activated carbon as a base material, a binder having a hydroxyl group, and a solvent to obtain a mixture, molding the mixture to obtain a molded product, and drying the molded product. 【0018】 The mesoporous silica substrate is silicon dioxide with uniform and regular pores, a pore diameter of 1.5 to 30 nm, and a specific surface area of ​​700 to 1400 m². 2 The value is / g. In particular, MCM-41 has hexagonally regular pores. Specifically, in this embodiment, mesoporous silica with an average pore diameter of 2.5 nm or more can be used as the substrate. This makes it possible to adjust the average pore diameter of the adsorbent obtained by the manufacturing method of this embodiment to 3 nm or more. 【0019】 The activated carbon base material is a porous substance mainly composed of carbon, and has functional groups such as hydroxyl groups, phenyl groups, and carboxyl groups on its surface. The activated carbon base material has a BET specific surface area of ​​500 to 3000 m². 2 It is / g. 【0020】 Examples of binders containing hydroxyl groups include cellulose or its derivatives; and aqueous silicate solutions. A single binder may be used, or multiple binders may be used in combination. 【0021】 Examples of cellulose derivatives include cellulose ethers such as methylcellulose, ethylcellulose, ethylmethylcellulose, carboxymethylcellulose, carboxyethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, benzylcellulose, tritylcellulose, cyanoethylcellulose, and aminoethylcellulose; and cellulose esters such as acetylcellulose, diacetylcellulose, and triacetylcellulose. 【0022】 Examples of silicates include sodium silicate and potassium silicate. Sodium silicate and potassium silicate may be used in the form of water glass or in powder form. 【0023】 The amount of binder mixed can be, for example, 1-20% by weight, 3-15% by weight, or 5-10% by weight relative to the substrate. 【0024】 Any solvent that is soluble in the binder can be used, such as water; alcohols such as methanol, ethanol, and propanol; carboxylic acids such as formic acid and acetic acid; and aprotic polar solvents such as acetone and acetonitrile. One solvent may be used alone, or multiple solvents may be used in mixture form. The amount of solvent mixed can be, for example, 10-200% by weight, 50-150% by weight, or 80-120% by weight relative to the substrate. 【0025】 The mixture of the substrate, binder, and solvent can be molded using a mold of any shape and size. The shape of the molded product after molding can be, for example, pellets, beads, prismatics, cylinders, plates, films, nonwoven fabrics, etc. 【0026】 The method for producing the siloxane compound adsorbent according to this embodiment may include a step of pressing the molded product after molding a mixture of the substrate, binder, and solvent. The pressing can be done, for example, using a press machine. The pressing pressure can be, for example, 1 to 30 MPa, 5 to 20 MPa, or 10 to 15 MPa. By pressing the molded product, the mechanical strength of the resulting adsorbent can be improved. 【0027】 The drying temperature and drying time are not particularly limited, as long as they are sufficient to dry (evaporate the solvent) the molded product of the mixture of the substrate, binder, and solvent. The drying temperature can be, for example, room temperature (25°C) to 100°C, 30 to 80°C, or 50 to 70°C. The drying method may be natural drying or drying using a drying oven. The drying time can be, for example, 10 minutes to 10 hours, 30 minutes to 5 hours, or 1 hour to 2 hours. 【0028】 The method for producing the siloxane compound adsorbent according to this embodiment may include a step of heat-treating the dried product after drying the molded product. The heat treatment temperature can be, for example, 150 to 500°C, 200 to 450°C, or 250 to 350°C. The heat treatment can be carried out using, for example, an oven, a firing furnace, or a sintering furnace. The heat treatment time can be, for example, 10 minutes to 10 hours, 30 minutes to 5 hours, or 1 hour to 2 hours. 【0029】 For example, when a siloxane compound adsorbent is applied to a spacecraft, the adsorbent is exposed to high temperatures of approximately 150°C or higher. As mentioned above, by heat-treating the dried material, it is possible to confirm in advance that the siloxane compound adsorbent can exhibit its adsorption performance even under high-temperature conditions. 【0030】 The method for producing the siloxane compound adsorbent according to this embodiment may include a step of adding an additive, to the extent that it does not impair the performance of the siloxane compound adsorbent of this disclosure. As the additive, a wide variety of commonly used additives can be used, such as pigments, reinforcing agents, antioxidants, and light stabilizers. 【0031】 <Siloxane compound adsorbent> When mesoporous silica is used as the substrate, the siloxane compound adsorbent obtained by the method for producing the siloxane compound adsorbent according to this embodiment contains mesoporous silica and a binder, has an average pore diameter of 3 nm or more, and has hydroxyl groups on its surface. 【0032】 The average pore size of the siloxane compound adsorbent can be adjusted by adjusting the pore size of the mesoporous silica (raw material) substrate. When mesoporous silica is used as the substrate, the average pore size of the siloxane compound adsorbent may be, for example, 3 nm to 10 nm, 3 nm to 8 nm, or 3 nm to 6 nm. In particular, when the average pore size is 3 nm to 6 nm, the siloxane compound can penetrate the pores, and the hydroxyl groups on the pore surface can easily bind to the siloxane compound, resulting in stronger adsorption of the siloxane compound. 【0033】 When activated carbon is used as the base material, the siloxane compound adsorbent obtained by the method for producing the siloxane compound adsorbent according to this embodiment comprises activated carbon and a binder, and has hydroxyl groups, phenyl groups and carboxyl groups on its surface. 【0034】 The BET specific surface area of ​​the siloxane compound adsorbent can be adjusted by adjusting the BET specific surface area of ​​the activated carbon (raw material) of the base material. When activated carbon is used as the base material, the BET specific surface area of ​​the siloxane compound adsorbent is, for example, 1000 m². 2 / g or more 2000m 2 / g or less, 1100m 2 / g or more 1900m 2 / g or less, or 1200m 2 / g or more 1800m 2 It may be less than / g. 【0035】 The amount of siloxane compound adsorbed by the siloxane compound adsorbent of this embodiment is 50% by weight or more, and depending on the case, 70% by weight or more, and 100% by weight or more, relative to the siloxane compound adsorbent before adsorption of the siloxane compound. In particular, when mesoporous silica is used as the base material, an adsorption amount of 100% by weight or more of siloxane compound can be achieved, and when activated carbon is used as the base material, an adsorption amount of 70% by weight or more of siloxane compound can be achieved. 【0036】 The siloxane compound adsorbent of this embodiment can suppress the desorption of siloxane compounds and maintain adsorption even under temperature conditions of 150°C or higher, and optionally 170°C or higher or 200°C or higher, after the adsorption of siloxane compounds. 【0037】 <Summary of the First Embodiment> As described above, the method for producing the siloxane compound adsorbent of this embodiment includes mixing mesoporous silica or activated carbon as a base material, a binder having hydroxyl groups, and a solvent to obtain a mixture, molding the mixture to obtain a molded product, and drying the molded product. When the base material is mesoporous silica, the siloxane compound adsorbent obtained by the production method of this embodiment contains mesoporous silica and a binder, has an average pore size of 3 nm or more, and has hydroxyl groups on its surface. When the base material is activated carbon, the siloxane compound adsorbent obtained by the production method of this embodiment contains activated carbon and a binder, and has hydroxyl groups, phenyl groups, and carboxyl groups on its surface. Such a siloxane compound adsorbent has a high adsorption capacity for siloxane compounds and an adsorption retention capacity at high temperatures. 【0038】 [Second Embodiment] In the first embodiment described above, a method for producing a siloxane compound adsorbent and the siloxane compound adsorbent obtained thereby were explained. In the second embodiment, examples of applications of the siloxane compound adsorbent will be described. 【0039】 The siloxane compound adsorbent described herein has high adsorption performance for siloxane compounds and can adsorb siloxane compounds present in the environment. Therefore, it can be installed, for example, on or near components of precision instruments that generate siloxane compounds. Examples of precision instruments include, but are not limited to, electric vehicles, optical materials, solar panels, gas sensors, and spacecraft. The siloxane compound adsorbent may be applied to precision instruments in its immediately-manufactured form, or after appropriate secondary molding. Specifically, the siloxane compound adsorbent can be applied in any form depending on the application location, such as pellets, granules processed and then molded into filters, held in marshmallow gel, film, or nonwoven fabric. Marshmallow gel is a general term for a silicone composition monolithic porous body obtained by copolymerizing alkoxide silicates. 【0040】 By applying the siloxane compound adsorbent disclosed herein to precision instruments, the adhesion of siloxane compounds to the instruments can be suppressed, thereby simplifying maintenance of precision instruments and reducing the frequency of maintenance. As a result, it leads to a reduction in costs and risks related to maintaining the performance of precision instruments. When the siloxane compound adsorbent disclosed herein is applied to various measuring instruments, observation instruments, etc., it is possible to prevent the deterioration of measurement data and observation data due to contamination by siloxane compounds. 【0041】 Furthermore, the siloxane compound adsorbent disclosed herein can maintain its adsorption performance of siloxane compounds even under high-temperature and vibrational conditions, and can therefore be used in high-temperature environments and withstand vibrations. This reduces the frequency of maintenance and replacement of the siloxane compound adsorbent itself. 【0042】 The siloxane compound adsorbent of this disclosure may also be in the form of a paint. That is, the paint of this disclosure contains a siloxane compound adsorbent. The paint contains components that are widely used in paints, such as solvents, resins, pigments, and additives. As for the type of paint, any type can be selected depending on the application, such as water-based paints, powder coatings, and resin coatings. 【0043】 [Differentiation] This disclosure is not limited to the embodiments described above, but includes various modifications. For example, the embodiments described above are described in detail for the purpose of illustrating this disclosure, and do not necessarily have to include all the configurations described. Furthermore, parts of one embodiment can be replaced with the configurations of another embodiment. Furthermore, configurations of other embodiments can be added to the configuration of one embodiment. Furthermore, parts of the configuration of each embodiment can be added, deleted, or replaced with parts of the configurations of other embodiments. [Examples] 【0044】 The following describes embodiments of the technology of this disclosure. 【0045】 Experimental Example 1: Use of Mesoporous Silica 【0046】 [Example 1] <Manufacturing of adsorbents> 2 g of methylcellulose (cellulose 400) and 10-20 mL of distilled water were mixed, and then 20 g of mesoporous silica (MCM-41) with an average pore size of 2.73 nm was added and mixed to obtain a paste-like mixture. This mixture was filled into a mold (cylindrical shape with a diameter of 10 mm), and a pressure of 10 MPa was applied using a press machine for 5 minutes to obtain pellets with a thickness of approximately 10 mm or more. These pellets were dried in a dryer set to 60°C. This obtained the adsorbent (pellet-like) according to Example 1. 【0047】 <Evaluation of the presence of hydroxyl groups> Using a Fourier transform infrared spectrophotometer (Frontier by Perkin Elmer), infrared (IR) spectra of the following four samples 1 to 4 were measured by the ATR method. The resolution of the measurement was 4 cm -1 as follows. Sample 1: Adsorbent according to Example 1 Sample 2: Adsorbent according to Example 1 adsorbed with hexamethylcyclotrisiloxane (D3) Sample 3: Hexamethylcyclotrisiloxane (D3) Sample 4: Mesoporous silica (MCM-41) raw material 【0048】 Figure 1A shows the infrared spectra of Samples 1 to 4. The vertical axis in Figure 1A indicates the transmittance (%), and the horizontal axis indicates the wavenumber (cm -1 ). Region 1 shown in Figure 1A indicates the stretching vibration band of the OH group, and Region 2 indicates the bending vibration band of the OH group. 【0049】 Figure 1B is an enlarged infrared spectrum of Region 1 shown in Figure 1A. As shown in Figure 1B, compared with the spectrum of Sample 4 (mesoporous silica raw material), the spectrum of Sample 1 (adsorbent according to Example 1) has a larger area of the OH group stretching vibration band at a wavenumber of 3100 - 3700 cm -1 . From this, it can be seen that by manufacturing the adsorbent as in Example 1, the OH groups increased compared to the raw mesoporous silica. Also, the maximum absorption is at a wavenumber of 3392 cm -1 in Sample 4, whereas it shifted to a wavenumber of 3,400 cm -1 in Sample 1. 【0050】 Figure 1C is an enlarged infrared spectrum of Region 2 shown in Figure 1A. As shown in Figure 1C, compared with the spectrum of Sample 4 (mesoporous silica raw material), the spectrum of Sample 1 (adsorbent according to Example 1) has a larger area of the OH group bending vibration band at a wavenumber of 1580 - 1680 cm -1 . From this, it can be seen that by manufacturing the adsorbent as in Example 1, the OH groups increased compared to the raw mesoporous silica. Further, the maximum absorption is at a wavenumber of 1630 cm in Sample 4-1 While this can be seen in [location], in sample 1, the wavenumber is 1650 cm⁻¹. -1 They shifted to that. 【0051】 <Evaluation of pore size and specific surface area of ​​adsorbent> Using a high-precision gas / vapor adsorption analyzer (BELSORP®-28SA, manufactured by Nippon Bell Co., Ltd.), measurements were performed by nitrogen adsorption to determine the BET specific surface area and total pore volume of the sample. The pretreatment conditions were 150°C for 10 hours, and measurements were performed under conditions of -194°C using liquid nitrogen. 【0052】 The adsorbent in Example 1 had an average pore size of 3 nm and a specific surface area of ​​954.16 m². 2 The value was / g. Thus, compared to the average pore size of the raw material mesoporous silica of 2.73 nm, the average pore size of the adsorbent obtained in Example 1 was larger at 3 nm (the pore distribution shifted to the right). 【0053】 <Evaluation of the adsorption performance of siloxane compounds> (Measurement of adsorption amount of siloxane compounds) The change in weight of the adsorbent before and after the adsorption of the siloxane compound was measured, and the adsorption capacity [mg / g] (weight %) of the siloxane compound was calculated. The amount of siloxane compound adsorbed by the adsorbent in Example 1 was 243.330% by weight relative to the weight of the adsorbent after the adsorption of the siloxane compound. From this, it was found that the adsorbent in Example 1 had high adsorption performance for siloxane compounds. 【0054】 (Evaluation of temperature resistance of adsorption) Using a TG-GC-MS instrument, the weight change of the adsorbent was measured in a temperature range from room temperature to 500°C, and the released gas components were identified. The gas components included a gas with a mass-to-charge ratio (m / z) of 207. 【0055】 Figure 1D is a graph showing the analysis results of the adsorbent according to Example 1 using a TG-GC-MS apparatus. In Figure 1D, the horizontal axis represents temperature, and the vertical axis represents the ionic intensity of the gas component. As shown in Figure 1D, the intensity of the gas component remained almost constant and low from room temperature up to approximately 200°C, but began to increase from approximately 200°C, peaking at approximately 380°C. From this, it was found that the adsorbent of Example 1 maintained adsorption with minimal desorption of siloxane compounds even under temperature conditions of approximately 200°C. 【0056】 [Example 2] <Manufacturing of adsorbents> The adsorbent material according to Example 2 was obtained in the same manner as in Example 1, except that the pellets were dried in a dryer and then further heat-treated at 150°C for 2 hours. 【0057】 <Evaluation of pore size and specific surface area of ​​adsorbent> The pore size and specific surface area of ​​the adsorbent according to Example 2 were measured in the same manner as in Example 1. The pore size of the adsorbent in Example 2 was an average of 3 nm, and the specific surface area was 1003.1 m². 2 It was / g. 【0058】 <Evaluation of the adsorption performance of siloxane compounds> The adsorption capacity of the adsorbent in Example 2 for siloxane compounds was calculated in the same manner as in Example 1, and was found to be 247.649% by weight. This indicates that the adsorbent in Example 2 has high adsorption performance for siloxane compounds. 【0059】 Furthermore, the emitted gas was analyzed using a TG-GC-MS apparatus in the same manner as in Example 1. Figure 2 is a graph showing the analysis results of the adsorbent in Example 2 using a TG-GC-MS apparatus. As shown in Figure 2, the intensity of the gas components remained almost constant and low from room temperature to approximately 200°C, but began to increase from approximately 200°C, peaking at approximately 410°C. From this, it was found that the adsorbent in Example 2 maintained adsorption with minimal desorption of siloxane compounds even under temperature conditions of approximately 200°C. 【0060】 [Example 3] <Manufacturing of adsorbents> An adsorbent according to Example 3 was obtained in the same manner as in Example 1, except that cellulose 4000 was used instead of cellulose 400 as methylcellulose. 【0061】 <Evaluation of pore size and specific surface area of ​​adsorbent> The pore size and specific surface area of ​​the adsorbent according to Example 3 were measured in the same manner as in Example 1. The pore size of the adsorbent in Example 3 was an average of 3 nm, and the specific surface area was 1029 m². 2 It was / g. 【0062】 <Evaluation of the adsorption performance of siloxane compounds> The adsorption capacity of the adsorbent in Example 3 for siloxane compounds was calculated in the same manner as in Example 1, and was found to be 245.553% by weight. This indicates that the adsorbent in Example 3 has high adsorption performance for siloxane compounds. 【0063】 Furthermore, the emitted gas was analyzed using a TG-GC-MS apparatus in the same manner as in Example 1. Figure 3 is a graph showing the analysis results of the adsorbent in Example 3 using a TG-GC-MS apparatus. As shown in Figure 3, the intensity of the gas components remained almost constant and low from room temperature to approximately 200°C, but began to increase from approximately 200°C, peaking at approximately 410°C. From this, it was found that the adsorbent in Example 3 maintained adsorption with minimal desorption of siloxane compounds even under temperature conditions of approximately 200°C. 【0064】 [Example 4] <Manufacturing of adsorbents> An adsorbent according to Example 4 was obtained in the same manner as in Example 2, except that cellulose 4000 was used instead of cellulose 400 as methylcellulose. 【0065】 <Evaluation of pore size and specific surface area of ​​adsorbent> The pore size and specific surface area of ​​the adsorbent according to Example 4 were measured in the same manner as in Example 1. The pore size of the adsorbent in Example 4 was an average of 3 nm, and the specific surface area was 1001.6 m². 2 It was / g. 【0066】 <Evaluation of the adsorption performance of siloxane compounds> The adsorption capacity of the adsorbent in Example 4 for siloxane compounds was calculated in the same manner as in Example 1, and was found to be 249.417% by weight. This indicates that the adsorbent in Example 4 has high adsorption performance for siloxane compounds. 【0067】 Furthermore, the emitted gas was analyzed using a TG-GC-MS apparatus in the same manner as in Example 1. Figure 4 is a graph showing the analysis results of the adsorbent in Example 4 using a TG-GC-MS apparatus. As shown in Figure 4, the intensity of the gas components remained almost constant and low from room temperature to approximately 200°C, but began to increase from approximately 200°C, peaking at approximately 405°C. From this, it was found that the adsorbent in Example 4 exhibited minimal desorption of siloxane compounds and maintained adsorption even under temperature conditions of approximately 200°C. 【0068】 [Example 5] <Manufacturing of adsorbents> An adsorbent according to Example 5 was obtained in the same manner as in Example 1, except that water glass (aqueous solution of sodium silicate) was used instead of methylcellulose. 【0069】 <Evaluation of pore size and specific surface area of ​​adsorbent> The pore size and specific surface area of ​​the adsorbent according to Example 5 were measured in the same manner as in Example 1. The pore size of the adsorbent in Example 5 was an average of 3 nm, and the specific surface area was 1032.3 m². 2 It was / g. 【0070】 <Evaluation of the adsorption performance of siloxane compounds> The adsorption capacity of the adsorbent in Example 5 for siloxane compounds was calculated in the same manner as in Example 1, and was found to be 115.972% by weight. This indicates that the adsorbent in Example 5 has high adsorption performance for siloxane compounds. 【0071】 Furthermore, the emitted gas was analyzed using a TG-GC-MS apparatus in the same manner as in Example 1. Figure 5 is a graph showing the analysis results of the adsorbent in Example 5 using a TG-GC-MS apparatus. As shown in Figure 5, the intensity of the gas components remained almost constant and low from room temperature to approximately 200°C, but began to increase from approximately 200°C, peaking at approximately 425°C. From this, it was found that the adsorbent in Example 5 maintained adsorption with minimal desorption of siloxane compounds even under temperature conditions of approximately 200°C. 【0072】 [Example 6] <Manufacturing of adsorbents> The adsorbent according to Example 6 was obtained in the same manner as in Example 2, except that water glass (aqueous solution of sodium silicate) was used instead of methylcellulose. 【0073】 <Evaluation of pore size and specific surface area of ​​adsorbent> The pore size and specific surface area of ​​the adsorbent according to Example 6 were measured in the same manner as in Example 1. The average pore size of the adsorbent in Example 6 was 3 nm, and the specific surface area was 999.23 m². 2 It was / g. 【0074】 <Evaluation of the adsorption performance of siloxane compounds> The adsorption capacity of the adsorbent in Example 6 for siloxane compounds was calculated in the same manner as in Example 1, and was found to be 120.968% by weight. This indicates that the adsorbent in Example 6 has high adsorption performance for siloxane compounds. 【0075】 Furthermore, the emitted gas was analyzed using a TG-GC-MS apparatus in the same manner as in Example 1. Figure 6 is a graph showing the analysis results of the adsorbent in Example 6 using a TG-GC-MS apparatus. As shown in Figure 6, the intensity of the gas components remained almost constant and low from room temperature to approximately 200°C, but began to increase from approximately 200°C, peaking at approximately 350°C. From this, it was found that the adsorbent in Example 6 maintained adsorption with minimal desorption of siloxane compounds even under temperature conditions of approximately 200°C. 【0076】 [Comparative Example 1] <Manufacturing of adsorbents> 20 g of commercially available mesoporous silica (MCM-41) powder was prepared and used as the adsorbent for Comparative Example 1. In other words, in Comparative Example 1, the mesoporous silica was used as an unmolded adsorbent without being mixed with methylcellulose and distilled water. 【0077】 <Evaluation of pore size and specific surface area of ​​adsorbent> The pore size and specific surface area of ​​the adsorbent according to Comparative Example 1 were measured in the same manner as in Example 1. The average pore size of the adsorbent in Comparative Example 1 was 2.73 nm, and the specific surface area was 1327.7 m². 2 The value was / g. Thus, it was found that the adsorbent of Comparative Example 1 had a smaller pore size compared to Examples 1-6. 【0078】 <Evaluation of the adsorption performance of siloxane compounds> The adsorption capacity of the adsorbent in Comparative Example 1 for siloxane compounds was calculated in the same manner as in Example 1, and was found to be 46.682% by weight. Thus, it was found that the adsorbent in Comparative Example 1 adsorbed significantly less siloxane compounds compared to Examples 1 to 6. This is thought to be due to the small pore size of the adsorbent in Comparative Example 1, which makes it difficult for siloxane compounds to adsorb into the pores, and the low hydroxyl group content of the adsorbent because it was not mixed with methylcellulose. 【0079】 Furthermore, the emitted gas was analyzed using a TG-GC-MS apparatus in the same manner as in Example 1. Figure 7 is a graph showing the analysis results of the adsorbent according to Comparative Example 1 using a TG-GC-MS apparatus. As shown in Figure 7, the intensity of the gas component began to increase in the temperature range from room temperature to approximately 110°C, peaking at approximately 110°C. Furthermore, at approximately 175°C, the intensity of the gas component became 0. From this, it was found that the adsorbent of Comparative Example 1 could not maintain adsorption because the siloxane compound was desorbed in a temperature environment above room temperature. 【0080】 Experimental Example 2: Use of Zeolite 【0081】 [Comparative Example 2] <Manufacturing of adsorbents> The adsorbent according to Comparative Example 2 was obtained in the same manner as in Example 1, except that 20 g of zeolite (F9) was used instead of mesoporous silica and the weight of methylcellulose was 1 g. 【0082】 <Evaluation of pore size and specific surface area of ​​adsorbent> The pore size and specific surface area of ​​the adsorbent in Comparative Example 2 were measured in the same manner as in Example 1. The average pore size of the adsorbent in Comparative Example 2 was 0.7 nm, and the total specific surface area was 899.67 m². 2 The value is / g, and the external specific surface area is 54.469 m². 2 It was / g. 【0083】 <Evaluation of the adsorption performance of siloxane compounds> The adsorption capacity of the adsorbent in Comparative Example 2 for siloxane compounds was calculated in the same manner as in Example 1, and was found to be approximately 0.370% by weight. Thus, it was found that the adsorbent in Comparative Example 2 adsorbed significantly less siloxane compounds compared to Examples 1 to 6. This is thought to be because the adsorbent in Comparative Example 2 had an average pore size of 0.7 nm, which is smaller than the average pore size of 3 nm in Examples 1 to 6, and therefore the siloxane compounds could not penetrate the pores. 【0084】 Furthermore, the emitted gas was analyzed using a TG-GC-MS apparatus in the same manner as in Example 1. Figure 8 is a graph showing the analysis results of the adsorbent according to Comparative Example 2 using a TG-GC-MS apparatus. As shown in Figure 8, the intensity of the gas components was always 0 in the temperature range of room temperature to 500°C, indicating that the siloxane compound could not be adsorbed at all. 【0085】 [Comparative Example 3] <Manufacturing of adsorbents> 20 g of commercially available zeolite (F9) was prepared and used as the adsorbent for Comparative Example 3. In other words, in Comparative Example 3, the zeolite was used as an unmolded adsorbent without being mixed with methylcellulose and distilled water. 【0086】 <Evaluation of pore size and specific surface area of ​​adsorbent> The pore size and specific surface area of ​​the adsorbent according to Comparative Example 3 were measured in the same manner as in Example 1. The average pore size of the adsorbent in Comparative Example 3 was 0.7 nm, and the total specific surface area was 877.74 m². 2 The value is / g, and the external specific surface area is 27.387 m². 2 It was / g. 【0087】 <Evaluation of the adsorption performance of siloxane compounds> The adsorption capacity of the adsorbent in Comparative Example 3 for the siloxane compound was calculated in the same manner as in Example 1, and was found to be 21.341% by weight. Thus, it was found that the adsorbent in Comparative Example 3 adsorbed significantly less siloxane compound compared to Examples 1 to 6. This is thought to be because the adsorbent in Comparative Example 3 had an average pore size of 0.7 nm, which is smaller than the average pore size of 3 nm in Examples 1 to 6, and therefore the siloxane compound could not penetrate the pores. 【0088】 Experimental Example 3: Use of Activated Carbon 【0089】 [Example 7] <Manufacturing of adsorbents> After mixing 1 g of methylcellulose (cellulose 400) with 10-20 mL of distilled water, 20 g of activated carbon was added and mixed to obtain a paste-like mixture. This mixture was filled into a mold (cylindrical with a diameter of 10 mm), and a pressure of 10 MPa was applied using a press machine for 5 minutes to obtain pellets with a thickness of approximately 10 mm or more. These pellets were dried in a dryer set to 60°C. This obtained the adsorbent according to Example 7. The BET pore size of the activated carbon (raw material) was an average of 3.4 nm, and the BET specific surface area was 2568 m². 2 It was / g. 【0090】 <Evaluation of pore size and specific surface area of ​​adsorbent> The pore size and specific surface area of ​​the adsorbent according to Example 7 were measured in the same manner as in Example 1. The average BET pore size of the adsorbent in Example 7 was 3.8 nm, and the BET specific surface area was 1122 m². 2 It was / g. 【0091】 <Evaluation of the adsorption performance of siloxane compounds> The adsorption capacity of the adsorbent in Example 7 for the siloxane compound was calculated in the same manner as in Example 1, and was found to be 72.646% by weight. Thus, it was found that the adsorbent in Example 7 adsorbed a larger amount of siloxane compound compared to Comparative Example 2, which used zeolite as a base material. This is thought to be because activated carbon has a larger specific surface area compared to zeolite, and because the functional groups of activated carbon have a stronger interaction with the siloxane compound. 【0092】 Furthermore, the emitted gas was analyzed using a TG-GC-MS apparatus in the same manner as in Example 1. Figure 9 is a graph showing the analysis results of the adsorbent according to Example 7 using a TG-GC-MS apparatus. As shown in Figure 9, the intensity of the gas components remained almost constant and low from room temperature to approximately 170°C, but began to increase from approximately 170°C, reaching a small peak at approximately 230°C, decreasing to approximately 270°C before rising again, and reaching a larger peak again at approximately 320°C. From this, it was found that the adsorbent of Example 7 maintained adsorption with minimal desorption of siloxane compounds even under temperature conditions of approximately 170°C. 【0093】 [Example 8] <Manufacturing of adsorbents> The adsorbent material according to Example 8 was obtained in the same manner as in Example 7, except that the pellets were dried in a dryer and then further heat-treated at 150°C for 2 hours. 【0094】 <Evaluation of pore size and specific surface area of ​​adsorbent> The pore size and specific surface area of ​​the adsorbent according to Example 8 were measured in the same manner as in Example 1. The average BET pore size of the adsorbent in Example 8 was 4.1 nm, and the BET specific surface area was 1402 m². 2 It was / g. 【0095】 <Evaluation of the adsorption performance of siloxane compounds> The adsorption capacity of the adsorbent in Example 8 for siloxane compounds was calculated in the same manner as in Example 1, and was found to be 70.747% by weight. This indicates that the adsorbent in Example 8 has high adsorption performance for siloxane compounds. 【0096】 Furthermore, the emitted gas was analyzed using a TG-GC-MS apparatus in the same manner as in Example 1. Figure 10 is a graph showing the analysis results of the adsorbent according to Example 8 using a TG-GC-MS apparatus. As shown in Figure 10, the intensity of the gas components remained almost constant and low from room temperature to approximately 170°C, but began to increase from approximately 170°C, reaching a small peak at approximately 230°C, decreasing to approximately 270°C before rising again, and reaching a larger peak again at approximately 330°C. From this, it was found that the adsorbent of Example 8 maintained adsorption with minimal desorption of siloxane compounds even under temperature conditions of approximately 170°C. 【0097】 [Example 9] <Manufacturing of adsorbents> The adsorbent according to Example 9 was obtained in the same manner as in Example 7, except that cellulose 4000 was used instead of cellulose 400 as methylcellulose. 【0098】 <Evaluation of pore size and specific surface area of ​​adsorbent> The pore size and specific surface area of ​​the adsorbent according to Example 9 were measured in the same manner as in Example 1. The average BET pore size of the adsorbent in Example 9 was 3.9 nm, and the BET specific surface area was 1197 m². 2 It was / g. 【0099】 <Evaluation of the adsorption performance of siloxane compounds> The adsorption capacity of the adsorbent in Example 9 for siloxane compounds was calculated in the same manner as in Example 1, and was found to be 71.514% by weight. This indicates that the adsorbent in Example 9 has high adsorption performance for siloxane compounds. 【0100】 Furthermore, the emitted gas was analyzed using a TG-GC-MS apparatus in the same manner as in Example 1. Figure 11 is a graph showing the analysis results of the adsorbent according to Example 9 using a TG-GC-MS apparatus. As shown in Figure 11, the intensity of the gas components remained almost constant and low from room temperature to approximately 170°C, but began to increase from approximately 170°C, reaching a small peak at approximately 230°C, decreasing to approximately 270°C before rising again, and reaching a larger peak again at approximately 320°C. From this, it was found that the adsorbent of Example 9 maintained adsorption with minimal desorption of siloxane compounds even under temperature conditions of approximately 170°C. 【0101】 [Example 10] <Manufacturing of adsorbents> The adsorbent according to Example 10 was obtained in the same manner as in Example 8, except that cellulose 4000 was used instead of cellulose 400 as methylcellulose. 【0102】 <Evaluation of the adsorption performance of siloxane compounds> The adsorption capacity of the adsorbent in Example 10 for siloxane compounds was calculated in the same manner as in Example 1, and was found to be 72.840% by weight. This indicates that the adsorbent in Example 10 has high adsorption performance for siloxane compounds. 【0103】 Furthermore, the emitted gas was analyzed using a TG-GC-MS apparatus in the same manner as in Example 1. Figure 12 is a graph showing the analysis results of the adsorbent in Example 10 using a TG-GC-MS apparatus. As shown in Figure 12, the intensity of the gas components remained almost constant and low from room temperature to approximately 170°C, but began to increase from approximately 170°C, reaching a small peak at approximately 230°C, decreasing to approximately 270°C before rising again, and reaching a larger peak again at approximately 330°C. From this, it was found that the adsorbent in Example 10 exhibited minimal desorption of siloxane compounds and maintained adsorption even under temperature conditions of approximately 170°C. 【0104】 [Example 11] <Manufacturing of adsorbents> An adsorbent according to Example 11 was obtained in the same manner as in Example 7, except that water glass (aqueous solution of sodium silicate) was used instead of methylcellulose. 【0105】 <Evaluation of pore size and specific surface area of ​​adsorbent> The pore size and specific surface area of ​​the adsorbent according to Example 11 were measured in the same manner as in Example 1. The average BET pore size of the adsorbent in Example 11 was 3.6 nm, and the BET specific surface area was 1225 m². 2 It was / g. 【0106】 <Evaluation of the adsorption performance of siloxane compounds> The adsorption capacity of the adsorbent in Example 11 for siloxane compounds was calculated in the same manner as in Example 1, and was found to be 73.903% by weight. This indicates that the adsorbent in Example 11 has high adsorption performance for siloxane compounds. 【0107】 Furthermore, the emitted gas was analyzed using a TG-GC-MS apparatus in the same manner as in Example 1. Figure 13 is a graph showing the analysis results of the adsorbent according to Example 11 using a TG-GC-MS apparatus. As shown in Figure 13, the intensity of the gas components remained almost constant and low from room temperature to approximately 170°C, but began to increase from approximately 170°C, reaching a small peak at approximately 225°C, decreasing to approximately 270°C before rising again, and reaching a larger peak again at approximately 335°C. From this, it was found that the adsorbent of Example 11 maintained adsorption with minimal desorption of siloxane compounds even under temperature conditions of approximately 170°C. 【0108】 [Example 12] <Manufacturing of adsorbents> The adsorbent according to Example 12 was obtained in the same manner as in Example 8, except that water glass (aqueous solution of sodium silicate) was used instead of methylcellulose. 【0109】 <Evaluation of pore size and specific surface area of ​​adsorbent> The pore size and specific surface area of ​​the adsorbent according to Example 12 were measured in the same manner as in Example 1. The average BET pore size of the adsorbent in Example 12 was 3.7 nm, and the BET specific surface area was 1534 m². 2 It was / g. 【0110】 <Evaluation of the adsorption performance of siloxane compounds> The adsorption capacity of the adsorbent in Example 12 for siloxane compounds was calculated in the same manner as in Example 1, and it was found to be 70.818% by weight. From this, it was found that the adsorbent in Example 12 has high adsorption performance for siloxane compounds. 【0111】 Furthermore, the emitted gas was analyzed using a TG-GC-MS apparatus in the same manner as in Example 1. Figure 14 is a graph showing the analysis results of the adsorbent in Example 12 using a TG-GC-MS apparatus. As shown in Figure 14, the intensity of the gas components remained almost constant and low from room temperature to approximately 160°C, but began to increase from approximately 160°C, reaching a small peak at approximately 230°C, decreasing to approximately 270°C before rising again, and reaching a larger peak again at approximately 330°C. From this, it was found that the adsorbent in Example 12 maintained adsorption with minimal desorption of siloxane compounds even under temperature conditions of approximately 160°C.

Claims

[Claim 1] The process involves mixing mesoporous silica or activated carbon as a base material, a binder having hydroxyl groups, and a solvent to obtain a mixture. The mixture is molded to obtain a molded product, The process includes drying the molded product. A method for producing a siloxane compound adsorbent having an average pore size of 3 nm or more and 10 nm or less. [Claim 2] The method for producing a siloxane compound adsorbent according to claim 1, wherein the binder is cellulose or a derivative thereof, or an aqueous silicate solution. [Claim 3] The method for producing a siloxane compound adsorbent according to claim 1, wherein the solvent is a solvent that dissolves the binder. [Claim 4] A method for producing a siloxane compound adsorbent according to claim 1, further comprising pressing the molded product before drying the molded product. [Claim 5] A method for producing a siloxane compound adsorbent according to claim 1, further comprising heat-treating the dried material after the drying process. [Claim 6] It comprises mesoporous silica and a binder having a hydroxyl group. A siloxane compound adsorbent having an average pore size of 3 nm to 10 nm and hydroxyl groups on its surface. [Claim 7] The siloxane compound adsorbent according to claim 6, wherein the binder is cellulose or a derivative thereof, or an aqueous silicate solution. [Claim 8] A precision instrument comprising a siloxane compound adsorbent according to claim 6, installed near a component that generates siloxane compounds. [Claim 9] A paint containing the siloxane compound adsorbent described in claim 6 as a component.

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