JP5690075B2 - Siloxane remover and filter using the same - Google Patents

Description

  The present invention relates to a siloxane remover (or adsorbent) and a filter such as a gas sensor that are effective for efficiently removing siloxane.

  Various chemicals are used in various environments (such as living environments), including the use of volatile organic compounds (VOC) and switching to low-volatile solvents in response to VOC measures. Contains substances. In particular, a lot of chemical substances are contained in the living environment accompanying the increase in airtightness of the housing structure accompanying energy saving. For example, due to silicone patties, anti-fogging agents, polishes, deodorant sprays, cosmetics (hairdressing etc.), shampoos, treatments, etc. Siloxanes (cyclic siloxanes) are included.

  Such siloxanes cause various harmful effects. For example, siloxanes burn to produce fine silicon oxide, which adheres to a gas turbine or a gas engine and causes power generation failure. In Japanese Patent No. 3776904 (Patent Document 1), a plurality of adsorption towers filled with a resin adsorbent made of a styrene-divinylbenzene copolymer are provided, and a gas to be treated containing water is circulated in at least one adsorption tower. The siloxane is adsorbed and removed, and at the same time, a regeneration gas at room temperature or higher and 150 ° C. or lower is passed through at least one other adsorption tower to regenerate the resin adsorbent by desorption of the siloxane. A siloxane removal method is disclosed in which the regeneration is performed in parallel, and the aeration of the gas to be treated and the regeneration gas is switched after a certain time, and the adsorption treatment and the regeneration treatment are exchanged to continuously remove siloxane. In this method, the siloxane can be removed by utilizing the adsorption / desorption property of the styrene-divinylbenzene copolymer (resin adsorbent) with respect to siloxane, and the adverse effects associated with the generation of fine particle silicon oxide can be eliminated.

  On the other hand, siloxanes can also cause false alarms by sensors (such as gas sensors). That is, on the upstream side of the gas sensor container, a filter that prevents passage of poisoning components of the sensor and allows passage of detected components (for example, carbon monoxide, methane, etc.) is disposed. This filter contains an adsorbent such as activated carbon. However, since siloxanes are less adsorbable to the adsorbent than VOC components, siloxanes pass through the filter and reach the sensor. In addition, when the VOC component is adsorbed and accumulated in the adsorbent, the adsorbent adsorbing ability is reduced, so that siloxanes easily pass through the filter and reach the sensor as time passes. And since siloxanes form a silica film on the sensor surface and sensitize to various gases, the number of false alarms is increasing.

Japanese Patent No. 3776904 (Claims)

  Accordingly, an object of the present invention is to provide a siloxane remover (or adsorbent) useful for efficiently adsorbing and removing siloxanes, a method for removing siloxanes, and a filter useful for removing siloxanes (or The object is to provide a gas sensor provided with this filter.

  Other objects of the present invention include a siloxane remover (or adsorbent) that selectively adsorbs siloxanes over a long period of time, a method for removing siloxanes, and a filter useful for removing siloxanes (or this filter). Providing a gas sensor).

  Still another object of the present invention is to provide a siloxane remover (or adsorption) capable of suppressing the passage or permeation of siloxanes, which are poisonous components, over a long period of time without reducing the detection responsiveness to the detected components in a gas sensor. Agent), a method for removing siloxanes, and a filter.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have made selective and efficient use of cyclic siloxanes when a resin having a sulfonic acid group (such as a strong acid ion exchange resin) is contacted with cyclic siloxanes. The present invention was completed by finding that polymerization and the resin having a sulfonic acid group efficiently absorb or adsorb siloxanes while efficiently transmitting the components to be detected (carbon monoxide, methane, etc.).

  That is, the siloxane remover of the present invention is a siloxane remover for removing cyclic siloxanes and contains a resin having a sulfonic acid group. The resin having a sulfonic acid group may be at least one selected from a sulfonated styrene-divinylbenzene copolymer, a perfluorosulfonic acid ionomer, a sulfonated styrene-olefin copolymer, and a sulfonated polyphosphazene. . Resin having a sulfonic acid group is a porous material, for example, a monofunctional aromatic vinyl monomer having a sulfonic acid group and one vinyl group, and a polyfunctional aromatic vinyl type having a plurality of vinyl groups. A monomer copolymer containing at least a monomer (or a monomer containing at least a monofunctional aromatic vinyl monomer having one vinyl group and the polyfunctional aromatic vinyl monomer) (A copolymer obtained by sulfonating a copolymer of a monomer) (for example, a strong acid ion exchange resin), or a porous body in which the resin having a sulfonic acid group is supported on a porous carrier. The cyclic siloxane may be at least one selected from 6-membered siloxane, 8-membered siloxane, and 10-membered siloxane.

  The present invention relates to a method for removing a cyclic siloxane by contacting a fluid to be treated containing cyclic siloxanes with the siloxane remover; a filter disposed on the upstream side of a gas sensor, wherein the siloxane remover is Also included is a filter (or a filter composed of the siloxane remover).

  In this specification, acrylic monomers and methacrylic monomers are collectively referred to as (meth) acrylic monomers.

  In the present invention, since the siloxane remover is composed of a resin having a sulfonic acid group, cyclic siloxanes can be efficiently polymerized, and siloxanes that are poisoning components of the sensor can be removed. In addition, siloxanes can be selectively removed over a long period of time. Furthermore, in a gas sensor, the passage or permeation of siloxanes can be suppressed over a long period of time without degrading the detection responsiveness to the component to be detected. Therefore, the siloxane remover (or adsorbent) is useful as a filter (or a gas sensor equipped with this filter) for removing siloxanes.

  The siloxane remover of the present invention contains a resin having a sulfonic acid group and reacts with cyclic siloxanes to effectively remove the cyclic siloxane. The resin containing a sulfonic acid group may be various resins having a sulfonic acid group, such as a sulfonated olefin resin, a sulfonated styrene resin, and a sulfonated sulfone resin. Resins having sulfonic acid groups include sulfonated styrene-divinylbenzene copolymers (for example, styrenesulfonic acid-divinylbenzene copolymers, sulfonated styrene-divinylbenzene copolymers), perfluorosulfonic acid ionomers ( A polymer having a carbon-fluorine skeleton and a perfluoro side chain having a sulfonic acid group, such as a copolymer of tetrafluoroethylene and perfluoro [(2- (2-sulfoethoxy) propyl) vinyl ether], for example, “Nafion ”(Registered trademark), etc.), sulfonated styrene-olefin copolymers (eg, sulfonated styrene-ethylene copolymers (Aldrich), sulfonated styrene-ethylene / butylene-styrene block copolymers (Aldrich) Sulfonylbenzene units such as Copolymers of olefins unit), sulfonated polyphosphazene (Aldrich) in many cases is like. These sulfonic acid-containing resins can be used alone or in combination of two or more.

  The resin having a sulfonic acid group may be granular (or bead-like) or thin-film, and in order to increase the contact area with the cyclic siloxane, the porous body (eg, granular, bead-like, thin-film) A porous body). The porous body includes (a) a monofunctional aromatic vinyl monomer having a sulfonic acid group and one vinyl group, a polyfunctional aromatic vinyl monomer having a plurality of vinyl groups, and A copolymer of a monomer containing at least a monomer (or a copolymer of a monomer containing at least a monofunctional aromatic vinyl monomer having one vinyl group and the polyfunctional aromatic vinyl monomer) A copolymer obtained by sulfonating a polymer) and (b) a porous body in which the resin having a sulfonic acid group is supported on a porous carrier.

In the porous body (a), examples of the monofunctional monomer include aromatic vinyl monomers [eg, styrene; vinyl toluene, vinyl xylene, p-ethyl styrene, pt-butyl styrene; α-methylstyrene; styrenesulfonic acid or a salt thereof], (meth) acrylic monomer [eg (meth) acrylic acid; eg, methyl (meth) acrylate, ethyl (meth) acrylate, (meth) (Meth) acrylic such as propyl acrylate, butyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate acid linear or branched C _1-16 alkyl esters; (meth) hexyl acrylate cycloalkyl; (meth) phenyl acrylate; (meth) acrylate Benzyl; glycidyl (meth) acrylate; (meth) acrylic acid 2-hydroxyethyl, (meth) (meth) acrylic acid hydroxyalkyl C _2-4 alkyl esters of acrylic acid 2-hydroxypropyl], fatty acid vinyl ester Monomers (such as vinyl acetate and vinyl propionate), olefins (such as α-C _2-6 olefins such as ethylene and propylene), halogen-containing vinyl monomers such as vinyl chloride, unsaturated polyvalent carboxylic acids or Its acid anhydride (for example, maleic acid, itaconic acid, citraconic acid or its acid anhydride), imide-based monomer [for example, maleimide; N—C _1-4 alkylmaleimide, N-cyclohexylmaleimide, N-phenyl N-substituted maleimides such as maleimide] and the like.

These monofunctional monomers can be used alone or in combination of two or more. Preferred monofunctional monomers include aromatic vinyl monomers or styrene monomers (styrene, vinyltoluene, α-methylstyrene, etc.), (meth) acrylic monomers [(meth) acrylic acid, (Meth) acrylic acid linear or branched C _1-16 alkyl ester, (meth) acrylic acid glycidyl, (meth) acrylic acid hydroxy C _2-4 alkyl ester, etc.]. These aromatic vinyl monomers and (meth) acrylic monomers can also be used alone or in combination of two or more. Further, when an aromatic vinyl monomer is used, maleic acid or maleic anhydride may be used in combination. In a preferred embodiment, the monofunctional monomer is at least a monofunctional aromatic vinyl monomer (that is, a monofunctional aromatic vinyl monomer having one vinyl group or a styrene monomer). Including.

As the polyfunctional monomer, various monomers that can introduce a crosslinked structure and form a porous structure, such as a polyfunctional (meth) acrylic monomer [ethylene glycol di (meth) acrylate, propylene, etc. C _2-10 alkylene glycol di (meth) acrylate such as glycol di (meth) acrylate, butanediol di (meth) acrylate, hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate; diethylene glycol di (meth) Polyalkylene glycol di (meth) such as acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate Acrylate; Bisphenol di (meth) in which the hydroxyl group of an adduct obtained by adding alkylene oxide to bisphenols such as 3,3-bis (4- (meth) acryloylethoxyphenyl) propane is esterified with (meth) acrylic acid Acrylates and the like], polyfunctional aromatic vinyl monomers [divinylbenzene, divinyltoluene and the like] and the like. These polyfunctional monomers can be used alone or in combination of two or more. A preferred polyfunctional monomer includes at least a polyfunctional aromatic vinyl monomer (a plurality, particularly a polyfunctional aromatic vinyl monomer having two vinyl groups).

  If necessary, three or more (such as glycerin tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, etc. A polyfunctional monomer having a (meth) acryloyl group may be used in combination.

  In order to improve the affinity with cyclic siloxanes, at least one of the monofunctional monomer and polyfunctional monomer (especially both monomers) is at least an aromatic monomer. The body is preferably included. That is, the porous body is preferably a porous aromatic resin having a crosslinked structure. The sulfonic acid group may be introduced by copolymerizing a monomer having a sulfonic acid group such as styrene sulfonic acid or a salt thereof, and may be a copolymer of a monofunctional monomer and a polyfunctional monomer. The polymer may be introduced by sulfonation.

  The ratio (weight ratio) of the monofunctional aromatic vinyl monomer to the polyfunctional aromatic vinyl monomer forms a crosslinked structure and a porous structure, and depends on the molecular size of the cyclic siloxanes. The contact efficiency with the cyclic siloxanes may be in a range that does not impair the contact efficiency. For example, the former / the latter = 95/5 to 25/75 (for example, 90/10 to 30/70), preferably 80/20 to 40 / It may be about 60 (for example, 75/25 to 40/60), more preferably about 70/30 to 40/60 (for example, 60/40 to 40/60).

The specific surface area of the porous body (a) is, for example, about 150 to 2000 m ² / g (for example, 180 to 1500 m ² / g), preferably about 200 to 1200 m ² / g (for example, 220 to 1000 m ² / g). It may be about 175 to 1000 m ² / g. Moreover, an average pore diameter is 1-30 nm (for example, 2.5-20 nm), for example, Preferably it is 4-17 nm (for example, 5-15 nm), More preferably, it is about 6-15 nm (for example, 7-15 nm). There may be. Furthermore, the pore volume is 0.2 to 5 ml / g (eg 0.3 to 3 ml / g), preferably 0.5 to 2.5 ml / g (eg 0.6 to 2.2 ml / g). It may be about 0.5 to 2 ml / g (for example, 0.6 to 1.7 ml / g). If the specific surface area or pore volume is too small, the removal amount of cyclic siloxanes cannot be increased, and if the specific surface area or pore volume is too large, it may be difficult to prepare a porous material. On the other hand, if the pore size is too small, it is difficult to form a reaction site for cyclic siloxanes. If the pore size is too large, various components are adsorbed and the selective removal of cyclic siloxanes is often impaired. In the porous body (a), fine pores are developed to the inside of the copolymer (or resin), and a uniform pore diameter is formed.

  Examples of such a porous body (a) include a styrene sulfonic acid-divinylbenzene copolymer, a styrene sulfonic acid- (meth) acrylic acid-divinylbenzene copolymer, and a styrene sulfonic acid-styrene-divinylbenzene copolymer. And styrene sulfonic acid- (meth) acrylic acid ester-divinylbenzene copolymer). The porous body (a) may be a resin (porous resin) obtained by sulfonating a porous resin having a crosslinked structure such as a styrene-divinylbenzene copolymer with sulfuric acid or the like. Furthermore, these porous bodies (a) may be alkali metal salts (lithium, sodium, potassium salts, etc.), ammonium salts, amine salts (alkylamine salts such as trimethylamine salts) and the like. As the preferred porous body (a), a strong acid ion exchange resin (for example, a sulfonated styrene-divinylbenzene copolymer, a styrenesulfonic acid-divinylbenzene copolymer, etc.) is often used. These porous bodies (a) are commercially available as ion exchange resins.

In the porous body (b), examples of the porous carrier include activated carbon, zeolite, silica, and alumina. These carriers can also be used alone or in combination of two or more. The specific surface area of the carrier may be, for example, about 200 to 2500 m ² / g (for example, 300 to 2000 m ² / g), preferably about 500 to 1750 m ² / g (for example, 750 to 1500 m ² / g). The average pore diameter may be, for example, about 2 to 20 nm (for example, 3 to 17 nm), preferably about 4 to 15 nm (for example, 5 to 15 nm), or about 5 to 10 nm. Furthermore, the pore volume is 0.3-5 ml / g (for example 0.5-3 ml / g), preferably 0.7-2.5 ml / g (for example 0.8-2.2 ml / g). It may be a degree.

  The amount of the resin having a sulfonic acid group may be, for example, 1 to 100 parts by weight, preferably 5 to 75 parts by weight, and more preferably about 10 to 50 parts by weight with respect to 100 parts by weight of the carrier.

  The specific surface area, average pore diameter and pore volume of the porous body (b) may be the same as those of the porous body (a).

The specific surface area, average pore diameter and pore volume can be measured with a BET analyzer using N ₂ as an adsorbed gas.

  Specific examples of such a porous carrier (b) include, for example, a polymer having a carbon carrier and a perfluoro side chain having a sulfonic acid group (for example, “Nafion” (registered trademark) on a silica carrier. ) Is supported (for example, “Nafion (registered trademark) SAC-13” (Aldrich) and the like).

  The siloxane remover of the present invention is usually in a granular or granular form.

The siloxane remover of the present invention has a reaction site (sulfonic acid group site) that reacts with cyclic siloxanes, and also reacts efficiently with cyclic siloxanes to cause ring-opening polymerization of cyclic siloxanes. Examples of the siloxanes (cyclic siloxanes) include siloxane cyclic dimers (or 4-membered rings) [(CH ₃ ) ₂ SiO] ₂ (D2), cyclic trimers (or 6-membered rings) [(CH ₃ ) ₂ SiO] ₃ (D3), cyclic tetramer (or 8-membered ring) [(CH ₃ ) ₂ SiO] ₄ (D4), cyclic pentamer (or 10-membered ring) [(CH ₃ ) ₂ SiO] ₅ (D5), cyclic hexamer (D6) and the like. The removing agent of the present invention can efficiently remove a single siloxane or a plurality of siloxanes among these siloxanes. In addition, the main components among siloxanes in the environment (for example, in the atmosphere) are a cyclic trimer (D3), a cyclic tetramer (D4), and a cyclic pentamer (D5).

The siloxane remover only needs to contain the resin having the sulfonic acid group, and may be composed of the resin having the sulfonic acid group (first remover) alone, or the first remover and the adsorbent (for example, , Activated carbon, zeolite, silica, alumina, etc.). Other adsorbents can be used alone or in combination of two or more. Another preferred adsorbent (especially adsorbent in granular or granular form) is activated carbon. The specific surface area of the adsorbent may be, for example, about 500 to 2500 m ² / g (for example, 600 to 2000 m ² / g), preferably about 700 to 1750 m ² / g (for example, 750 to 1500 m ² / g). . The average pore diameter may be, for example, about 1 to 20 nm (for example, 2 to 17 nm), preferably about 3 to 15 nm (for example, 5 to 15 nm), or about 1 to 10 nm (for example, 1 to 5 nm). It may be. Furthermore, the pore volume is 0.2 to 5 ml / g (eg 0.3 to 3 ml / g), preferably 0.5 to 2.5 ml / g (eg 0.6 to 2.2 ml / g). It may be a degree.

  The resin having a sulfonic acid group and the adsorbent may be mixed and used, or may be used in a form separated into layers in the flow direction of the fluid to be treated. For example, a layer containing a resin or adsorbent having a sulfonic acid group may be positioned on the upstream side, and a layer containing a resin having an adsorbent or a sulfonic acid group may be positioned on the downstream side.

  The ratio between the resin having a sulfonic acid group and the adsorbent is the former / the latter (weight ratio) = 100/0 to 30/70, preferably 100/0 to 40/60, more preferably 100/0 to 50/50. It may be a degree.

  Cyclic siloxanes can be removed by bringing a treated fluid containing cyclic siloxanes into contact with the removing agent. The fluid to be treated may be a liquid (such as an aqueous solution or an organic solvent solution), but is usually a gas. The concentration of siloxanes in the fluid to be treated is, for example, about 1 ppb to 100 ppm (for example, 1 ppb to 20 ppm), preferably 1 ppb to 1 ppm, and more preferably about 1 ppb to 500 ppb (for example, 1 ppb to 100 ppb). The fluid to be treated (especially the gas to be treated) is water, carbon monoxide, carbon dioxide, nitrogen monoxide, nitrogen dioxide, hydrocarbons (aliphatic hydrocarbons such as methane, ethane, propane, butane, hexane, cyclohexane, etc. Alicyclic hydrocarbons, aromatic hydrocarbons such as benzene and toluene), halogenated hydrocarbons (such as trichloroethylene), ethers (such as dimethyl ether and diethyl ether), and the like. Further, the gas to be treated may be air containing cyclic siloxanes.

The porous copolymer (or the removal agent containing the porous copolymer) may be brought into contact with the cyclic siloxanes by being left or present in the atmosphere of the fluid to be treated (or gas to be treated). The treatment fluid (or gas to be treated) can be brought into contact with the porous copolymer (or a removing agent containing the porous copolymer) in a batch, semi-batch, or continuous manner. When the fluid to be treated (or gas to be treated) is processed continuously, the flow rate of the fluid to be treated (or gas to be treated) is 100 g of the porous copolymer (or the removal agent containing the porous copolymer). On the other hand, it may be about 100 mL / min to 200 L / min, preferably 1 to 100 L / min, more preferably about 1 to 60 L / min at normal temperature and normal pressure (temperature 20 to 25 ° C., pressure 1 atm). The space velocity (SV) of the fluid to be treated (or gas to be treated) may be, for example, about 100 to 50000 h ⁻¹ , preferably 1000 to 30000 h ⁻¹ , more preferably about 5000 to 20000 h ⁻¹ .

  The fluid to be treated (or gas to be treated) may be pressurized and brought into contact with the removal agent, but the treatment of the fluid to be treated (or gas to be treated) is usually performed at normal pressure. The adsorption treatment can be performed, for example, at a temperature of about 0 to 100 ° C. (preferably 10 to 50 ° C., more preferably 15 to 35 ° C.).

  The siloxane remover of the present invention reacts (or polymerizes) with the cyclic siloxanes that are poisoning components or sensitizing components of the sensor and selectively removes them. Therefore, the removing agent is suitable as a filter material disposed upstream of a sensor (for example, a sensor of an industrial or household gas alarm). More specifically, a sensor (such as a gas sensor) for detecting a predetermined detection component usually includes a hollow cylinder having an inlet and an outlet, and an upstream side (inlet side) of the cylinder. A filter disposed in the cylinder for removing contaminant components (such as poisoning components of the sensor), and a sensor disposed in a cylinder downstream of the filter (for example, the bottom of the cylinder) It has. In addition, the filter composed of the removing agent (for example, the filter for the particulate removing agent) is disposed in the cylinder with a breathable support (such as a mesh-shaped support) disposed on the inlet side of the cylinder. It is supported in a form filled with a breathable support (such as a mesh-like support) and is disposed in the cylinder. Moreover, the inflow port of the said cylinder can be formed in appropriate places, such as the center part of the upstream edge part of a cylinder. The detection value from the sensor is compared with a reference value, and when the detection value exceeds the reference value, an alarm notifies that the concentration of the toxic component or the combustible component has increased.

  Although the detection component by such a sensor can be selected according to the use of the sensor, the removal agent selectively and efficiently removes siloxanes without adsorbing the detection component [carbon monoxide, methane, etc.]. . Therefore, when the sensor filter is composed of the removing agent, the passage or permeation of siloxanes can be suppressed for a long period of time, and the occurrence of a false alarm can be prevented without deteriorating the detection responsiveness to the detected component. The sensor can be selected according to the type of component to be detected. For carbon monoxide, a conventional sensor (for example, catalytic combustion type, semiconductor type, electrochemical type sensor), for flammable components such as methane, A sensor (for example, contact combustion type, semiconductor type sensor) or the like can be used.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

Example 1
A strong acid ion exchange resin having a sulfonic acid group ("Diaion SK1BH" manufactured by Mitsubishi Chemical Corporation) is dried and placed in an aluminum container and precisely weighed (to the last 4 digits). The aluminum container containing siloxane (D3) was sealed in a dry desiccator and left in a constant temperature bath at 40 ° C. for 20 hours. The desiccator used was a desiccator that was previously dried by blowing dry nitrogen gas. The aluminum container was taken out of the thermostatic bath, the weight of the strong acid ion exchange resin was measured, and the polymerization amount of the cyclic siloxane under low humidity conditions (weight increase rate after drying) was measured.

Example 2
In Example 1, in a desiccator, an aluminum container containing a strong acid ion exchange resin (“Diaion SK1BH” manufactured by Mitsubishi Chemical Corporation), an aluminum container containing a six-membered ring siloxane (D3), and water The amount of cyclic siloxane polymerized in the presence of saturated water vapor (the rate of increase in weight after drying) was measured in the same manner as in Example 1 except that the contained aluminum container was sealed.

Comparative Example 1
Instead of the strong acid ion exchange resin, a weakly acidic resin having a carboxyl group (“HL415”, low molecular weight polyacrylic acid, manufactured by Nippon Shokubai Co., Ltd.) was used in the same manner as in Example 1 under low humidity conditions. The amount of cyclic siloxane polymerization (weight increase rate after drying) was measured.

Comparative Example 2
In the same manner as in Example 1, except that a weakly acidic resin having a carboxyl group (“AS58”, high molecular weight polyacrylic acid, manufactured by Nippon Shokubai Co., Ltd.) is used in place of the strong acid type ion exchange resin, low humidity conditions The amount of cyclic siloxane polymerization (weight increase rate after drying) was measured.

  The results are shown in Table 1.

  In addition, 0.5 g of the products produced in Examples 1 and 2 and 1 g of tetrahydrofuran (THF) were mixed and eluted, separated by filtration, and then the molecular weight was measured by gel permeation chromatography. That is, a molecular weight measuring device (DC-980-50 880-PU IR-930 865-CO (manufactured by Jasco)) is equipped with a packed column (Showdex KF-804L, manufactured by Showa Denko KK) as an eluent. Tetrahydrofuran (THF without a stabilizer (manufactured by Wako Pure Chemical Industries, Ltd.)) was used, and measurement was performed at a column temperature of 30 ° C. at 1.0 mL / min. As a result, in Example 1, the number average molecular weight (Mn) of the ring-opening polymer of cyclic siloxane was 160,000, and in Example 2, the number average molecular weight (Mn) of the ring-opening polymer of cyclic siloxane was 420,000.

Further, 0.5 g of the product produced in Examples 1 and 2 and 1 g of heavy solvent CDCl ₃ were mixed and stirred for 1 hour, followed by filtration to prepare a filtrate (sample). JNM GSX-270 (JEOL) When a nuclear magnetic resonance spectrum ¹ H-NMR was measured by 270 MHz manufactured by Co., Ltd., a chemical shift was observed at 0.07 ppm in any of the copolymers of Examples 1-2. The chemical shift of 6-membered ring siloxane (D3) is observed at 0.17 ppm.

  The present invention removes or separates cyclic siloxanes by efficiently and selectively adsorbing them. Therefore, it is useful not only for separating and removing cyclic siloxanes in various fields, for example, industrially, but also for separating cyclic siloxanes in the environment. Moreover, it is useful as a filter of a gas sensor for detecting a component to be detected (carbon monoxide, methane, etc.) by separating and removing siloxanes which are poisoning components.

Claims (5)

  A filter that is disposed on the inlet side upstream of the gas sensor disposed on the discharge port side of the hollow cylinder and includes a siloxane remover for polymerizing and removing cyclic siloxanes, The filter in which the siloxane remover includes a strong acid ion exchange resin having a sulfonic acid group.   The strong acid ion exchange resin having a sulfonic acid group is at least one selected from a sulfonated styrene-divinylbenzene copolymer, a perfluorosulfonic acid ionomer, a sulfonated styrene-olefin copolymer, and a sulfonated polyphosphazene. The filter according to claim 1. Strongly acidic ion-exchange resin having a sulfonic acid group, a porous, specific surface area 150~1500m ² / g, The filter of claim 1, wherein having an average pore diameter of 5 to 15 nm.   The filter according to any one of claims 1 to 3, wherein the cyclic siloxane is at least one selected from 6-membered siloxane, 8-membered siloxane, and 10-membered siloxane. A fluid to be treated containing cyclic siloxanes and a detection component is brought into contact with a filter disposed on the inlet side of the hollow cylinder to remove the cyclic siloxanes and disposed on the outlet side of the hollow cylinder. and a method of detecting the detection component in a gas sensor, wherein the filter comprises a siloxane removal agent to remove by polymerization of cyclic siloxanes, the siloxane removal agent, strongly acidic ion-exchange resin having a sulfonic acid group Including detection method.