JPWO2019065504A1 - Decomposition material and decomposition method using it - Google Patents

Abstract

An object of the present disclosure is to provide a decomposition material having higher catalytic activity and durability than conventional powder catalysts. The decomposition material according to the present disclosure is characterized by having a base material and a coating film provided on the surface of the base material, and the coating film contains mesoporous silica supporting particles containing platinum group elements as a catalyst. And. This decomposing material is capable of decomposing odorous substances containing at least one volatile compound selected from aldehydes, fatty acids, sulfide compounds, and nitrogen compounds, and / or ethylene even at low temperatures.

Description

The present disclosure relates to a decomposing material for odorous substances and a decomposing material for ethylene that reduces freshness. These decomposition materials are articles obtained by coating a base material with mesoporous silica powder carrying fine particles containing PGM (platinum group metal).

Mesoporous silica is silica having honeycomb (honeycomb) -like pores (mesopores) having a uniform pore diameter of 1 to 50 nm and having a large specific surface area of, for example, 300 to 2000 m ² / g. Mesoporous silica has at least one peak at a position where the d-interval of X-ray diffraction is larger than 2.0 nm (see, for example, Patent Document 1).

It has been reported that a powder in which platinum fine particles are supported on mesoporous silica decomposes ethylene and odorous substances at 20 ° C. or lower (see, for example, Patent Documents 1 and 2 and Non-Patent Document 1).

JP-A-2017-23889 International Publication WO2017-010472

Chuanxia Jiang, Kenji Hara, and Atsushi Fukuoka, Angew. Chem. Int. ED. , 2013, 52, 6265-6268

Since the catalysts disclosed in Patent Documents 1 and 2 and Non-Patent Document 1 take the form of powder or the like (hereinafter, also referred to as powder catalyst), the gas efficiently and uniformly contacts each particle of the powder. That was not always the case.

Further, if impurities are present at the inlet and the inside of the mesoporous silica, the contact with the platinum fine particles may be hindered when the gas is aerated, and the decomposition performance may be deteriorated. Therefore, it has been desired to highly stabilize the efficiency of decomposition.

Therefore, an object of the present disclosure is to provide a decomposition material having higher catalytic activity and durability than conventional powder catalysts.

As a result of diligent studies, the present inventors have solved the above problems by using mesoporous silica carrying particles containing platinum group elements as a uniform coating liquid and applying the coating liquid to a substrate to form a coating film. We found what we could do and completed the present invention. That is, the decomposition material according to the present invention has a base material and a coating film provided on the surface of the base material, and the coating film contains mesoporous silica supporting particles containing platinum group elements as a catalyst. It is characterized by.

In the decomposition material according to the present invention, it is preferable that the base material is any one of non-woven fabric, ceramic honeycomb, and paper honeycomb. By using such a base material, the coating film area per unit volume of the decomposition material can be increased.

In the decomposition material according to the present invention, it is preferable that the particles are platinum nanoparticles.

The decomposition material according to the present invention preferably further contains a binder.

The decomposition material according to the present invention preferably further contains a sedimentation inhibitor.

In the decomposition material according to the present invention, the binder is preferably at least one of an inorganic binder and an organic binder, and it is more preferable to use the inorganic binder and the organic binder together.

In the decomposition material according to the present invention, the sedimentation inhibitor is preferably at least one of fumed silica and thixotropy, and it is more preferable to use fumed silica and thixotropy in combination.

In the decomposition material according to the present invention, it is preferable that the inorganic binder is alumina.

In the decomposition material according to the present invention, the coating film contains 5 to 95 parts by mass of fumed silica as the sedimentation inhibitor and 1 to 95 parts by mass of alumina as the binder with respect to 100 parts by mass of the mesoporous silica. Is preferable. The dispersibility of these mixtures in the coating liquid is further improved, and a more uniform coating film can be obtained.

In the decomposition material according to the present invention, it is preferable that the fumed silica is 5 to 80 parts by mass and the alumina is 1 to 80 parts by mass with respect to 100 parts by mass of the mesoporous silica.

The decomposition material according to the present invention preferably further contains a thixotropic agent.

In the decomposition material according to the present invention, the coating film contains 10 to 50 parts by mass of an organic binder as the binder and 10 parts by mass or less of the thixo agent with respect to 100 parts by mass of the mesoporous silica. It is preferable to contain it.

In the decomposition material according to the present invention, it is preferable that the organic binder is a polyester resin or an acrylic resin.

In the decomposition material according to the present invention, it is preferable that the thixotropy is a maleic anhydride-based copolymer.

In the decomposition material according to the present invention, with respect to 100 parts by mass of the mesoporous silica, 10 to 50 parts by mass of a polyester resin or an acrylic resin as the organic binder and a maleic anhydride-based copolymer as the thixo agent are 1 part. It is preferably contained in an amount of 10 parts by mass.

The decomposing material according to the present invention comprises decomposing odorous substances including at least one volatile compound selected from aldehydes, fatty acids, sulfide compounds, and nitrogen compounds, and / or ethylene.

The method for decomposing odorous substances and / or ethylene according to the present invention includes the decomposing material according to the present invention and at least one volatile compound selected from aldehydes, fatty acids, sulfide compounds, and nitrogen compounds at low temperatures. It is characterized by contact with odorous substances and / or ethylene.

According to the present disclosure, a decomposition material having higher catalytic activity and durability than the conventional powder catalyst can be obtained. This decomposing material is capable of decomposing odorous substances containing at least one volatile compound selected from aldehydes, fatty acids, sulfide compounds, and nitrogen compounds, and / or ethylene even at low temperatures.

It is a surface electron microscope image of the decomposition material obtained in Example 2. It is a surface electron microscope image of the decomposition material obtained in Example 6. It is an enlarged view of FIG. It is a surface electron microscope image of the decomposition material obtained in Example 13. It is the surface electron microscope image of the part different from FIG. 4 of the decomposition material obtained in Example 13.

Hereinafter, the present invention will be described in detail by showing embodiments, but the present invention is not construed as being limited to these descriptions. The embodiments may be modified in various ways as long as the effects of the present invention are exhibited.

The decomposition material according to the present embodiment has a base material and a coating film provided on the surface of the base material, and the coating film contains mesoporous silica on which particles containing platinum group elements are supported as a catalyst.

In the present embodiment, the base material for forming the coating film containing mesoporous silica carrying particles containing platinum group elements may be any material to which a coating film for forming a coating film can be applied, and the shape thereof is, for example, a film. , Sheet shape, columnar shape, honeycomb shape and the like, non-woven fabric shape, woven cloth shape, paper shape and felt shape can be exemplified, and the surface to be applied may be smooth or uneven. Examples of the material are metal, resin, wood, paper, fiber, natural leather, synthetic leather, etc. If the viscosity of the coating liquid and the affinity between the coating surface and the coating liquid are adjusted so that the coating can be applied uniformly to the coating surface. Good.

When the decomposition material of the present embodiment is used in combination with various devices, machines and the like, a base material having a large surface area is preferable, and a honeycomb-shaped base material, a non-woven fabric or paper is preferable from the viewpoint of handling. The "honeycomb shape" as used herein has a broad meaning, and is not limited to a regular hexagon, but is a three-dimensional space-filling shape in which three-dimensional figures are arranged without interruption and has a communication hole, and the shape of the hole is circular. Or polygons such as triangles, quadrangles, pentagons, and hexagons can be exemplified. The shapes of the holes may all be the same, or may have two or more of these shapes.

Examples of the honeycomb-shaped base material include ceramic honeycombs and paper honeycombs. The component of the ceramic honeycomb is preferably a component selected from the group consisting of cordierite, silicon carbide, silicon nitride, alumina, mullite, aluminum titanate, titania and zirconia.

The paper honeycomb is preferably made of paper selected from the group consisting of kraft paper, K liner paper, reinforced core base paper, water resistant core base paper, aluminum hydroxide paper and the like. Further, among these papers, paper having insulating properties is preferable, and paper having nonflammability or flame retardancy is preferable.

The ceramic honeycomb can be produced by molding the above components into a predetermined shape by extrusion molding. Further, the paper honeycomb can be produced by continuously molding and laminating the above-mentioned paper in a flat plate shape, a wavy shape, a columnar shape, a honeycomb shape or the like. Select and use these as appropriate according to the application and environment. Ceramic honeycomb is preferable from the viewpoint of heat resistance, and paper honeycomb is preferable from the viewpoint of light weight.

Non-woven fabrics include aramid fiber, glass fiber, cellulose fiber, nylon fiber, vinylon fiber, polyester fiber, polyethylene fiber, polypropylene fiber, polyolefin fiber, rayon fiber, low density polyethylene resin, ethylene vinyl acetate resin, copolymerized polyamide resin, and copolymerization. It is made of fibers such as polyester resin and polyphenylene sulfide resin, and from the viewpoint of heat resistance, aramid fiber, glass fiber, cellulose fiber, nylon fiber, vinylon fiber, and polyester fiber are preferable, and they are flame-retardant and washable from the outside air. Polyester / modal acrylic resin fibers are more preferred from the standpoint of being rich in.

Paper is Japanese paper, Western paper, paper and paperboard (cardboard), newspaper roll paper (newspaper), printing / information paper (for information systems), non-coated printing paper (thin leaf paper), coated printing paper (coated paper / coat). Paper / lightweight coated paper), finely coated printing paper, special printing paper (high-quality color paper / government-made postcard), information paper (copy paper, inkjet paper, no-carbon paper, photosensitive paper, heat-sensitive paper), wrapping paper (wrapping paper) Paper (or envelope), sanitary paper (tissue paper, toilet paper, paper diapers, water-absorbent paper used for sanitary products, etc.), mixed paper (tracing paper, synthetic paper, insulating paper, release paper, rice paper (rice paper) It is made of paper such as paper rolls (paper rolls) and calligraphy paper), and the packaging material is said to be highly resistant to oils and lipids and flame retardant from the viewpoint of being highly waterproof and water resistant. From the viewpoint, each material for food packaging is further preferable.

In the decomposition material according to the present embodiment, the coating film is provided on the surface of the base material. The surface of the base material is the surface of the fibers constituting the non-woven fabric when the base material is a non-woven fabric, and when the base material is a honeycomb structure, not only the surface of the outer wall of the structure but also the communication holes. In the case of a film-like or sheet-like structure including the surface of the inner wall of the film or sheet, it is the surface of one side or both sides of the film or sheet. Further, when the base material is a porous body, the surface inside the pores is also included.

The coating film contains mesoporous silica carrying particles containing platinum group elements. In addition to mesoporous silica carrying particles containing platinum group elements, the coating film can be used as a binder, for example, an inorganic binder such as alumina, zirconia, or silica, a polyethylene resin, a polypropylene resin, or an acrylic resin such as methyl methacrylate. , ABS resin, polyester resin such as PET, phenol resin, epoxy resin, urethane resin, vinyl acetate resin, polyvinyl alcohol, cellulose such as carboxymethyl cellulose, arabia rubber, urethane, phenol, diene and other organic binders. Good. As will be described later, a settling inhibitor such as silica or fame silica added to the coating liquid to stabilize the formation of the coating film may be contained. The settling inhibitor also has a role of preventing mesoporous silica, an inorganic binder, or the like carrying particles containing platinum group elements contained in the coating liquid from settling with time. Further, the coating film may contain a thixotropic agent added for the purpose of stabilizing the coating process described later in addition to the above.

When a coating solution in which mesoporous silica carrying particles containing platinum group elements is dispersed in a solvent such as water or ethanol is applied to the surface of the substrate, if the coating film contains an inorganic binder, the coating solution is applied. Drying is promoted by heating and depressurizing the substrate after the above. At this time, water removal in the mesopores becomes easy. When the base material is made of an inorganic substance, the water content in the mesopores is removed by heating to 500 ° C. or higher. When the base material is made of an organic substance, it is preferably heated and dried under reduced pressure, and the conditions thereof include, for example, holding at 30 to 500 ° C. under normal pressure and 30 to 200 ° C. under reduced pressure of 133 Pa or less. The time is 0.1 to 24 hours. Even when the base material is made of an inorganic substance, the temperature may be raised or the pressure may be reduced. Further, when the coating film contains an inorganic binder, the water repellency of the coating film after drying is improved, and it is possible to prevent water from being mixed into the mesopores of the mesoporous silica when the decomposition material is used. Therefore, it is possible to prevent the catalyst from deteriorating its performance due to moisture. Further, when the coating film contains an inorganic binder, the adhesion between the coating film and the base material is improved.

When the coating film contains an inorganic binder, if the mass portion of the inorganic binder exceeds the mass portion of the mesoporous silica supporting the particles containing the platinum group element, the mesoporous silica carrying the particles containing the platinum group element in the coating liquid is used. In contrast to the fact that the dispersibility of the organic binder tends to decrease and the resulting catalytic activity tends to decrease, when an organic binder is contained, these reductions can be suppressed, and the mass part of the organic binder is the mass portion of the mesoporous silica. Can be exceeded. Further, after drying, the organic binder makes it possible to reduce the compatibility between the coating film and water. That is, the water repellency of the coating film after drying is improved, and it is possible to prevent water from being mixed into the mesopores of the mesoporous silica when the decomposition material is used. Therefore, it is possible to prevent the catalyst from deteriorating its performance due to moisture. Further, when the coating film contains an organic binder, the adhesion between the coating film and the base material is further improved as compared with the inorganic binder.

It is more preferable to use the inorganic binder and the organic binder together from the viewpoint that the water repellency of the coating film is improved and water can be further prevented from being mixed into the mesopores of the mesoporous silica when the decomposition material is used.

As the inorganic binder, alumina is preferable from the viewpoint of water repellent effect. As the organic binder, a polyester resin or an acrylic resin is preferable from the viewpoint of adhesion to the coating film.

The anti-sedimentation agent is added when the mesoporous silica is wet-dispersed and is dispersed in a solvent such as water or ethanol, and when the coating solution is concentrated and dried to form a powder, water is used. When the dry powder is redispersed with a solvent or the like to obtain a coating liquid for a coating film, precipitation of the dispersed powder is suppressed. The anti-settling agent is present in the coating when it becomes a dry coating. When the dispersibility of the coating liquid is good, a uniform coating film can be formed, and as a result, the gas permeability in the coating film can be improved.

The thixo agent (thix agent) has the effect of thickening the coating liquid and improves the coating property. For example, it is a copolymer of maleic anhydride and α-olefin such as ethylene or propylene, or styrene. Maleic anhydride-based copolymers can be mentioned. When the thixotropy is contained in the coating film, it is preferable that the mesoporous silica carrying the particles containing the platinum group element is suppressed from being separated from the coating film (powder drop).

The particles containing a platinum group element carried on mesoporous silica are elemental particles of platinum, rhodium, ruthenium, palladium, and iridium, or alloy particles thereof. As the alloy particles, ruthenium / palladium alloy and platinum / ruthenium alloy are preferable. The particle size of the particles is preferably 0.5 nm to 10 nm, more preferably 0.5 nm to 4 nm.

The pore diameter of the mesopores of mesoporous silica is preferably 1 to 50 nm, preferably 1 to 10 nm. BET specific surface area of mesoporous silica 300~2000m ² / g, preferably from 500 to 1500 ² / g.

The particles containing the platinum group element are preferably supported on the mesoporous silica by nucleating the particles from the solution containing the platinum group element and growing the particles in the presence of the mesoporous silica. By doing so, particles having a uniform particle size can be supported in the mesopores of mesoporous silica. Further, in the present embodiment, particles containing a platinum group element may be supported on the outer surface of the mesoporous silica.

In the decomposition material according to the present embodiment, it is preferable that the coating film further contains dry silica and alumina called fumed silica as a settling inhibitor. From the viewpoint of forming a uniform coating liquid, it is preferable to contain fumed silica and an inorganic binder, hydrophilicity is preferable as the fumed silica, and alumina is preferable as the inorganic binder. In particular, when hydrophilic fumed silica and hydrophilic alumina are present in the coating film together with mesoporous silica carrying a platinum group element, the adhesion between the base material and the coating film is improved and the gas permeability is improved, which is more preferable. .. In addition, the water repellency of the coating film is also enhanced.

The coating film contains 100 parts by mass or less of fumed silica, preferably 5 to 95 parts by mass, and 100 parts by mass or less of alumina, preferably 1 with respect to 100 parts by mass of mesoporous silica carrying particles containing platinum group elements. It is preferably contained in an amount of ~ 95 parts by mass, more preferably 5 to 80 parts by mass of fumed silica and 1 to 80 parts by mass of alumina. It is more preferable to contain 15 to 30 parts by mass of fumed silica and 1 to 10 parts by mass of alumina. By doing so, it is possible to prepare a coating liquid for a coating film in which powder does not substantially settle, and further, the above-mentioned gas permeability is improved and the water repellency of the coating film is also enhanced.

In the decomposition material according to the present embodiment, when the coating film contains an organic binder, it is preferable that the thixotropic agent is further contained. From the viewpoint of providing a uniform coating liquid, it is preferable to contain a thixotropic agent and an organic binder, a maleic anhydride-based copolymer is preferable as the thixotropic agent, and a polyester resin or an acrylic resin is preferable as the organic binder. .. In particular, when a thixotropic agent and a polyester resin or an acrylic resin which is an organic binder are present in the coating film together with mesoporous silica carrying a platinum group element, the adhesion between the base material and the coating film is improved and the gas permeability is improved. More preferable. In addition, the water repellency of the coating film is also enhanced. Both polyester-based resin and acrylic-based resin may be contained as the organic binder.

When an organic binder is used, the coating film contains 100 parts by mass or less of the organic binder, preferably 80 parts by mass or less, and 50 parts by mass of the thixo agent with respect to 100 parts by mass of mesoporous silica carrying particles containing platinum group elements. Hereinafter, it is preferable to contain 40 parts by mass or less, and more preferably 1 to 80 parts by mass of the organic binder and 1 to 40 parts by mass of the thixo agent. It is more preferable to contain 10 to 50 parts by mass of the organic binder and 1 to 10 parts by mass of the thixotropic agent. By doing so, it is easy to prepare a coating liquid for a coating film in which powder does not substantially settle, and the adhesion between the obtained coating film and the base material is improved, gas permeability is improved, and the coating film is repellent. Water quality is improved.

In the decomposition material according to the present embodiment, with respect to 100 parts by mass of mesoporous silica, 10 to 50 parts by mass of a polyester resin or an acrylic resin as an organic binder and 1 to 10 parts of a maleic anhydride-based copolymer as a thixo agent. It is preferably contained in parts by mass. It is more preferable to contain 10 to 25 parts by mass of a polyester resin or an acrylic resin as an organic binder and 1 to 5 parts by mass of a maleic anhydride-based copolymer as a thixotropic agent. In this case as well, both the polyester resin and the acrylic resin may be included as the organic binder.

The thickness of the coating film is appropriately set depending on the shape of the base material to be applied and the performance of the decomposition material, and 1 to 20 mesoporous silica particles carrying particles containing platinum group elements are formed in the film thickness direction of the coating film. It is preferable to have a stacked film thickness, and it is more preferable that the film thickness is one to ten stacked. From the viewpoint of the decomposition performance of the decomposed material and the decomposition efficiency per unit area of the decomposed material, the film thickness is approximately 0.1 μm or more, preferably 10 μm or more, more preferably 20 μm or more, and preferably 500 μm or less and 300 μm or less. , 200 μm or less is more preferable. For example, in the case of a base material made of a fibrous material such as a non-woven fabric, the film thickness of the coating film is about 1 to 300 μm, preferably about 20 to 200 μm. Further, in the case of a base material having a relatively flat portion such as a film, a sheet, a columnar or a honeycomb, the film thickness of the coating film is about 10 to 800 μm, preferably about 30 to 600 μm, preferably 30 to 100 μm. More preferred.

For example, as shown in FIG. 1, when the coating film was provided on the ceramic honeycomb, the thickness of the coating film was measured to be 50 to 90 μm and the average thickness was 70 μm per 10 places. .. Further, in FIGS. 2 and 3, a coating film is provided on the non-woven fabric, and the thickness range of the coating film is 35 to 150 μm. 4 and 5 show the case where the coating film is provided on the paper honeycomb, and the thickness range of the coating film is 280 to 500 μm. The average thickness of the coating film at about 10 locations shown in FIGS. 2 and 3 was measured to be around 90 μm, and the average thickness of the coating film at around 10 locations shown in FIGS. 4 and 5 was measured to be around 400 μm.

The particle size of the inorganic binder particles is preferably 5 to 95% of the film thickness of the coating film. When the particle size of the inorganic binder particles is in this range, the difference between the particle size of the inorganic binder particles and the particle size of the mesoporous silica particles carrying particles containing platinum group elements does not become too large. Mesoporous silica particles and inorganic binder particles tend to be uniformly mixed inside.

When the coating film contains both mesoporous silica particles carrying platinum group element particles and inorganic binder particles, the coating film contains mesoporous silica particles or inorganic binder particles carrying platinum group element particles. It is preferable that the coating film has a total thickness of 1 to 20 particles stacked in the film thickness direction, and more preferably a total of 1 to 10 particles are stacked.

The coating film is provided on the surface of the base material described above, but it is not necessary to provide the coating film on the entire surface as long as the decomposition performance of the decomposition material is within a desired range, and the coating film may be provided on a part of the surface of the base material. There may be a portion where the coating film is not provided on the surface of the base material. Further, the coating film may be discontinuous or intermittent on the surface of the base material, or the coating film may be provided in a spot shape on the surface of the base material.

The coating film can be formed by applying a coating liquid as described later to a base material and drying it, but especially if mesoporous silica carrying particles containing platinum group elements can be adhered to the base material. The method is not limited.

The coating film can usually be formed by applying a coating solution in which mesoporous silica carrying particles containing platinum group elements as described above is dispersed in a solvent such as water or ethanol to the surface of the base material and drying it. If necessary, the above-mentioned inorganic binder, organic binder, anti-sedimentant, thixotropy and the like can be added to the coating liquid to form a coating film containing these components. Further, various additives may be added to the coating liquid for the purpose of improving the dispersibility, viscosity and thixotropic property of the coating liquid.

The particle size of the particles containing the platinum group element is preferably 95% or less, more preferably 20 to 50% of the pore diameter of the mesopores of mesoporous silica. If it exceeds 95%, particles containing platinum group elements may grow irregularly in the mesopore, and it becomes difficult for gas to pass through the mesopore.

The mesoporous silica particles carrying particles containing platinum group elements in the coating film are preferably particles in which the mesopores are not destroyed and the particle surface is a crushed surface. If the particle surface is not a crushed surface, water or solvent that comes into contact with the coating liquid tends to remain invading the mesopore, and the air permeability of the gas to the mesopore may decrease, resulting in a decrease in catalytic activity. On the other hand, if the mesopore is a destroyed particle, the chance of contact between the catalyst particle and the gas is reduced, and the performance of the catalyst may be deteriorated.

In the present embodiment, the odorous substance is at least one selected from aldehydes such as formaldehyde and acetaldehyde, fatty acids such as formic acid and acetic acid, sulfide compounds such as hydrogen sulfide and methyl mercaptan, and nitrogen compounds such as trimethylamine and ammonia. Species of volatile compounds are exemplified.

The decomposition material of the present embodiment is used as a decomposition material that decomposes the odorous substance and ethylene at a low temperature, for example, 30 ° C. or lower. The decomposition temperature is usually −40 ° C. or higher, preferably −30 ° C. or higher. As a method to be used, for example, an odorous substance or ethylene to be decomposed may be brought into contact with the decomposition material of the present embodiment as a gas. In an environment where odorous substances and ethylene are gradually generated in the sealed space, if the decomposition material of the present embodiment is put in the sealed space from the beginning, even if odorous substances and ethylene are generated, they will be decomposed. , Their gas concentration can always be kept low. Further, in an environment where odorous substances and ethylene already exist in the sealed space, the decomposition materials of the present embodiment are put into the sealed space to decompose the odorous substances and ethylene, and their concentrations in the sealed space are reduced. Can be made to. Usually, the environment in which the decomposition material of the present invention is used is an environment in which an odorous substance or ethylene gas is generated or exists in the air, and the odorous substance or ethylene gas is oxidatively decomposed by oxygen in the air. The concentration of odorous substances and ethylene gas in the air is usually 1% or less, preferably 500 ppm or less, more preferably 200 ppm or less, but if necessary, it can be diluted with an inert gas such as air or nitrogen. Good. The decomposition of odorous substances and ethylene in the sealed space is a batch type decomposition method. Further, the decomposition material of the present invention may be forcibly brought into contact with an odorous substance or ethylene gas to decompose the odorous substance or ethylene gas. In the case of forced decomposition, it may be in a closed space or an open space, and an odorous substance or ethylene gas may be circulated. Also, oxygen is allowed to coexist for decomposition. The concentration of oxygen may be a stoichiometric amount required for oxygen decomposition of the substance to be decomposed or slightly higher (about 10%), and air may coexist.

The amount of decomposition material is appropriately set so that the decomposition rate is appropriate depending on the application. Normally, the amount of the decomposition material may be set so that the target gas is decomposed by 50% or more within 24 hours, and the decomposition material is almost completely decomposed, for example, 85% or more, preferably 90% or more, more preferably 95%. The amount of the decomposition material may be set so that the decomposition material can be decomposed.

Further, the decomposition method may be a continuous method in which the gas to be decomposed is continuously brought into contact with the decomposition material of the present embodiment. In the case of the continuous type, the flow velocity of the gas is appropriately set depending on the application, the usage environment, etc., and the decomposition material of the present embodiment may be continuously contacted while circulating the gas.

In the present embodiment, the coating method of the coating liquid is not particularly limited, and the coating liquid is applied to the surface of the base material with a brush, a roller, or the like, or the atomized coating liquid is sprayed with high-pressure air. Examples thereof include a method, a method of spraying the coating liquid at a high pressure, a method of air blowing (spraying) the coating liquid, a method of immersing the base material in the coating liquid, and the like. Of these methods, in the case of a honeycomb shape or a non-woven fabric shape, an air blow (spray) method or a method of immersing the base material in the coating liquid is preferable, and an excess coating liquid is aired after coating and before drying. It is preferable to blow it off with.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention will not be construed as being limited to Examples.

[Synthesis of platinum-supported mesoporous silica]
Based on the examples described in Patent Document 1 (Japanese Unexamined Patent Publication No. 2017-23889), the following was synthesized. Suspend 1 g of mesoporous silica (trade name TMPS-4 Earl trademark registered name TMPS manufactured by Taiyo Kagaku Co., Ltd.) in 50 mL of water, and add an aqueous solution of platinum compound (H ₂ PtCl ₆ ) so that the amount of Pt supported is 1% by mass. The mixture was added dropwise, and the aqueous solution was stirred at room temperature overnight. The solvent was distilled off by heating to 50 ° C. using an evaporator, and the obtained powder was vacuum dried at 60 ° C. for 16 to 18 hours, and then hydrogen gas was circulated at 30 mL / min at 150 ° C. for 2 The time was reduced to obtain mesoporous silica platinum powder (powder 1) carrying platinum. Further, 1.35 L of ion-exchanged water prepared by mixing 60% nitric acid with 150 g of (powder 1) was added, and the mixture was pulverized and dispersed for 15 minutes while stirring at room temperature using a zirconia bead mill. The obtained coating liquid was concentrated and dried to obtain a powder (powder 2).

Mesoporous silica platinum powder (powder 3) carrying platinum in the same manner as powder 1 except that an aqueous solution of platinum compound (H ₂ PtCl ₆ ) was dropped so that the amount of Pt supported in powder 1 was 5% by mass. ) Was obtained.

[Preparation of coating liquid 1]
Ion-exchanged water prepared by mixing and adjusting 60% nitric acid was added to the powder 2, and the solution added so as to have a concentration of 10% by mass was used as the coating solution 1.

[Preparation of coating liquid 2]
Fumed silica (AEROSIL® 200 manufactured by Nippon Aerosil Co., Ltd.) and alumina (AEROXIDE® Alu C manufactured by Nippon Aerosil Co., Ltd.) are added to 30 mL of coating liquid 1, and powder 2 and fumed silica are added. , Fumed silica and alumina are added, mixed, and mixed so that powder 2: fumed silica: alumina = 100: 28.5: 1.5 in terms of mass ratio of alumina in terms of solid content. Was used as the coating liquid 2.

[Adjustment of coating liquid 3]
In the preparation of the coating liquid 2, the powder 2, fumed silica, and alumina were mixed with fumed silica so that the ratio of parts by mass in terms of solid content was powder 2: fumed silica: alumina = 100: 24: 6. A coating liquid 3 was obtained in the same manner as in the preparation of the coating liquid 2 except that alumina was added.

[Preparation of coating liquid 4]
In 30 mL of the coating liquid 1, a thiox agent containing a maleic anhydride-based copolymer as a main component and a polyester-based resin (trade name: Boncoat SFC-55 manufactured by DIC) are added to powder 2, a texo agent, and a polyester-based resin. Add the thixo agent and the polyester resin so that the ratio of parts by mass in terms of solid content is powder 2: thixo agent: polyester resin = 100: 2: 22, mix them, and mix this with the coating liquid 4. did.

[Preparation of coating liquid 5]
In 30 mL of the coating liquid 1, a thiox agent containing a maleic anhydride-based copolymer as a main component and an acrylic resin are added to the powder in a solid content-equivalent mass ratio of the powder 2, the thiox agent, and the acrylic resin. 2: The thixo agent and the acrylic resin were added and mixed so that the ratio was 100: 2:22, and this was used as the coating liquid 5.

[Preparation of coating liquid 6]
A copolymer of fumed silica (Aerosil Japan Co., Ltd., AEROSIL® 200), alumina (Aerosil Japan Co., Ltd., AEROXIDE® Alu C), and maleic anhydride in 30 mL of the coating liquid 1. Polyester resin (trade name: Boncoat SFC-55 manufactured by DIC), which is mainly composed of powder 2, fumed silica, alumina, nitrogen agent, polyester resin by mass ratio in terms of solid content. Powder 2: Fumed silica: Alumina: Tixo agent: Polyester resin = 100: 4.8: 25.2: 20: 2 Add fumed silica, alumina, Tixo agent and polyester resin. , And this was used as the coating liquid 6.

[Preparation of coating liquid 7]
Ion-exchanged water prepared by mixing 60% nitric acid with the powder 3 was added so as to have a concentration of 10% by mass, and the solution was used as a coating solution 7.

[Preparation of coating liquid 8]
A copolymer of fumed silica (Aerosil Japan Co., Ltd., AEROSIL® 200), alumina (Aerosil Japan Co., Ltd., AEROXIDE® Alu C), and maleic anhydride in 30 mL of the coating liquid 7. Polyester resin (Boncoat SFC-55, trade name manufactured by DIC), which is mainly composed of powder 4, fumed silica, alumina, nitrogen agent, polyester resin by mass ratio in terms of solid content. Body 2: Fumed silica: Alumina: Tixo agent: Polyester resin = 100: 4.8: 25.2: 20: 2 Add fumed silica, alumina, Tixo agent and polyester resin. It was mixed and used as a coating liquid 8.

[Example 1] <Application of coating liquid 1 to non-woven fabric>
The coating liquid 1 is pre-weighed into a non-woven fabric (manufactured by Japan Vilene, acrylonitrile / modaacrylic) having three types of shapes: thickness 1 cm, length x width 5 cm x 5 cm, 10 cm x 10 cm, and 20 cm x 20 cm. The impregnated coating was applied, and the excess impregnating liquid was blown off by an air spray (manufactured by Kurita Seisakusho), and dried to form a coating film to obtain a decomposition material. The results of weighing after drying and determining the mass of platinum-supported mesoporous silica supported on the non-woven fabric from the difference from the mass of the non-woven fabric before impregnation coating were as follows.
5 cm x 5 cm, thickness 0.6 cm: 0.15 g
10 cm x 10 cm, thickness 0.6 cm: 0.60 g
20 cm x 20 cm, thickness 0.6 cm: 2.4 g

[Example 2] <Applying the coating liquid 1 to the ceramic honeycomb>
The coating liquid 1 is impregnated and coated on a ceramic honeycomb (manufactured by Iwao Ceramics Co., Ltd., 200 mesh) having three types of shapes, length x width: 5 cm x 5 cm and thicknesses of 3 cm, 5 cm, and 8 cm, respectively, which are weighed in advance. , The excess impregnating liquid was blown off by an air spray (manufactured by Kurita Seisakusho) and dried to form a coating film to obtain a decomposition material. The results of weighing after drying and determining the mass of platinum-supported mesoporous silica supported on the ceramic honeycomb from the difference from the mass of the non-woven fabric before impregnation coating were as follows.
5 cm x 5 cm, thickness 3 cm: 0.6 g
5 cm x 5 cm, thickness 5 cm: 1.0 g
5 cm x 5 cm, thickness 8 cm: 1.6 g

[Example 3] <Application of coating liquid 1 to paper honeycomb>
Paper honeycomb (manufactured by New Japan Feather Core, cell size 0) having a thickness of 1.0 cm, length x width 5 cm x 5 cm, 10 cm x 10 cm, 20 cm x 20 cm, and three types of coating liquid 1 weighed in advance. .85 cm) was impregnated and applied, and excess impregnated liquid was blown off by an air spray (manufactured by Kurita Seisakusho) and dried to form a coating film to obtain a decomposed material. The results of weighing after drying and determining the mass of platinum-supported mesoporous silica supported on the paper honeycomb from the difference from the mass of the non-woven fabric before impregnation coating were as follows.
5 cm x 5 cm, thickness 1.0 cm: 0.13 g
10 cm x 10 cm, thickness 1.0 cm: 0.52 g
20 cm x 20 cm, thickness 1.0 cm: 2.1 g

[Example 4] <Applying the coating liquid 2 to the paper honeycomb>
Apply the coating liquid 2 to a paper honeycomb (manufactured by Shin Nihon Feather Core, cell size 0.85 cm) having a thickness of 1 cm, a length x width of 5 cm x 5 cm, a length of 10 cm x 10 cm, and a shape of 20 cm x 20 cm. The impregnated coating was applied, and the excess impregnating liquid was blown off by an air spray (manufactured by Kurita Seisakusho) and dried to form a coating film to obtain a decomposition material. The results of weighing after drying and determining the mass of platinum-supported mesoporous silica supported on the paper honeycomb from the difference from the mass of the non-woven fabric before impregnation coating were as follows.
5 cm x 5 cm, thickness 1.0 cm: 0.04 g
10 cm x 10 cm, thickness 1.0 cm: 0.15 g
20 cm x 20 cm, thickness 1.0 cm: 0.60 g

[Example 5] <Applying the coating liquid 3 to the paper honeycomb>
A paper honeycomb (manufactured by Shin Nihon Feather Core, cell size 0.85 cm) having a thickness of 1 cm, a length of 5 cm x 5 cm, a length of 10 cm x 10 cm, and a shape of 20 cm x 20 cm, which is obtained by weighing the coating liquid 3 in advance. Was impregnated and applied, and an excess impregnating solution was blown off by an air spray (manufactured by Kurita Seisakusho) and dried to form a coating film to obtain a decomposition material. The results of weighing after drying and determining the mass of platinum-supported mesoporous silica supported on the paper honeycomb from the difference from the mass of the non-woven fabric before impregnation coating were as follows.
5 cm x 5 cm, thickness 1 cm: 0.07 g
10 cm x 10 cm, thickness 1 cm: 0.26 g
20 cm x 20 cm, thickness 1 cm: 1.0 g

[Example 6] <Application of coating liquid 3 to non-woven fabric>
The coating liquid 3 was applied to the non-woven fabric in the same manner as in Example 1 to obtain a decomposition material. The results of weighing after drying and determining the mass of platinum-supported mesoporous silica supported on the non-woven fabric from the difference from the mass of the non-woven fabric before impregnation coating were as follows.
5 cm x 5 cm, thickness 1 cm: 0.09 g
10 cm x 10 cm, thickness 1 cm: 0.35 g
20 cm x 20 cm, thickness 1 cm: 1.4 g

[Example 7] <Application of coating liquid 4 to non-woven fabric>
The coating liquid 4 was applied to the non-woven fabric in the same manner as in Example 1 to obtain a decomposition material. The results of weighing after drying and determining the mass of platinum-supported mesoporous silica supported on the non-woven fabric from the difference from the mass of the non-woven fabric before impregnation coating were as follows.
5 cm x 5 cm, thickness 0.6 cm: 0.08 g
10 cm x 10 cm, thickness 0.6 cm: 0.31 g
20 cm x 20 cm, thickness 0.6 cm: 1.2 g

[Example 8] <Application of coating liquid 5 to non-woven fabric>
The coating liquid 5 was applied to the non-woven fabric in the same manner as in Example 1 to obtain a decomposition material. The results of weighing after drying and determining the mass of platinum-supported mesoporous silica supported on the non-woven fabric from the difference from the mass of the non-woven fabric before impregnation coating were as follows.
5 cm x 5 cm, thickness 1 cm: 0.10 g
10 cm x 10 cm, thickness 1 cm: 0.40 g
20 cm x 20 cm, thickness 1 cm: 1.6 g

[Example 9] <Application of coating liquid 6 to paper honeycomb>
The coating liquid 6 was applied to the paper honeycomb in the same manner as in Example 3 to obtain a decomposition material.
The results of weighing after drying and determining the mass of platinum-supported mesoporous silica supported on the non-woven fabric from the difference from the mass of the non-woven fabric before impregnation coating were as follows.
5 cm x 5 cm, thickness 1 cm: 0.12 g
10 cm x 10 cm, thickness 1 cm: 0.45 g
20 cm x 20 cm, thickness 1 cm: 1.8 g

[Example 10] <Application of coating liquid 6 to non-woven fabric>
The coating liquid 6 was applied to the non-woven fabric in the same manner as in Example 1 to obtain a decomposition material.
The results of weighing after drying and determining the mass of platinum-supported mesoporous silica supported on the non-woven fabric from the difference from the mass of the non-woven fabric before impregnation coating were as follows.
5 cm x 5 cm, thickness 1 cm: 0.08 g
10 cm x 10 cm, thickness 1 cm: 0.35 g
20 cm x 20 cm, thickness 1 cm: 1.4 g

[Example 11] <Application of coating liquid 7 to paper honeycomb>
In the same manner as in Example 3, the coating liquid 7 was applied to the paper honeycomb to obtain a decomposition material.
The results of weighing after drying and determining the mass of platinum-supported mesoporous silica supported on the paper honeycomb from the difference from the mass of the non-woven fabric before impregnation coating were as follows.
5 cm x 5 cm, thickness 1 cm: 0.11 g
10 cm x 10 cm, thickness 1 cm: 0.44 g
20 cm x 20 cm, thickness 1 cm: 1.7 g

[Example 12] <Application of coating liquid 7 to non-woven fabric>
In the same manner as in Example 1, the coating liquid 7 was applied to the non-woven fabric to obtain a decomposed material. The results of weighing after drying and determining the mass of platinum-supported mesoporous silica supported on the non-woven fabric from the difference from the mass of the non-woven fabric before impregnation coating were as follows.
5 cm x 5 cm, thickness 0.6 cm: 0.12 g
10 cm x 10 cm, thickness 0.6 cm: 0.48 g
20 cm x 20 cm, thickness 0.6 cm: 1.9 g

[Example 13] <Application of coating liquid 8 to paper honeycomb>
The coating liquid 8 was applied to the non-woven fabric in the same manner as in Example 3 to obtain a decomposition material. The results of weighing after drying and determining the mass of platinum-supported mesoporous silica supported on the non-woven fabric from the difference from the mass of the non-woven fabric before impregnation coating were as follows.
5 cm x 5 cm, thickness 1 cm: 0.11 g
10 cm x 10 cm, thickness 1 cm: 0.44 g
20 cm x 20 cm, thickness 1 cm: 1.8 g

[Example 14] <Application of coating liquid 8 to non-woven fabric>
The coating liquid 8 was applied to the non-woven fabric in the same manner as in Example 1 to obtain a decomposition material. The results of weighing after drying and determining the mass of platinum-supported mesoporous silica supported on the non-woven fabric from the difference from the mass of the non-woven fabric before impregnation coating were as follows.
5 cm x 5 cm, thickness 0.6 cm: 0.09 g
10 cm x 10 cm, thickness 0.6 cm: 0.37 g
20 cm x 20 cm, thickness 0.6 cm: 1.5 g

[Comparative Example 1, Comparative Example 3, Comparative Example 4 and Comparative Example 5]
The powder 1 was not applied to the base material, and the powder 1 was designated as Comparative Example 1, Comparative Example 3, Comparative Example 4, and Comparative Example 5.

[Comparative Example 2]
The powder 2 was not applied to the base material, and the powder 2 was used as Comparative Example 2.

The platinum-supported mesoporous silica used in the coating liquids 1 to 3 and the powder of Comparative Example 2 were finely divided by the BET method using the adsorption isotherm obtained by the nitrogen adsorption / desorption measurement for the specific surface area ( _SBET ). The pore volume (V _tot ) was obtained by the BJH method, and the average pore diameter (D _meso ) was obtained by the αS plot method. The results are shown in Table 1. The BET specific surface area, average pore diameter, and total pore volume were measured using a specific surface area / pore distribution measuring device (BELSORP-mini II manufactured by Microtrac Bell Co., Ltd.).

[Ethylene decomposition test]
Ethylene decomposition tests of the decomposition materials and powders 1 and 2 obtained in Examples 1 to 14 at −20 ° C. and 20 ° C. were performed. "Smell bag" containing 2.6 L of gas containing ethylene (ethylene concentration 100 ppm, oxygen 20% by volume, balance nitrogen, manufactured by Taiyo Nippon Sanso Co., Ltd.) (bag capacity 3 L, bag size: 250 x 250 mm, material: polyester A decomposition material was added to a film (thickness 16 μm) / manufactured by Tokyo Glass Instruments Co., Ltd. so that the mass of platinum-supported mesoporous silica was 1 g. Specifically, in Examples 3 to 5, 9, 11 and 13, a size having a platinum-supported mesoporous silica mass of 1 g or less was cut out from a decomposed material having a thickness of 1 cm and a length × width of 20 cm × 20 cm. Further, in Example 2, a decomposed material having a thickness of 5 cm and a length × width of 5 cm × 5 cm was used. Further, in Examples 1, 6 to 8, 10, 12 and 14, a size having a platinum-supported mesoporous silica mass of 1 g or less was cut out from a decomposed material having a thickness of 0.6 cm and a length × width of 20 cm × 20 cm. In Comparative Example 1, 1 g of powder 1 was used by mass. In Comparative Example 2, 1 g of powder 2 was used by mass. After allowing to stand at −20 ° C. and 20 ° C. for 20 hours, the ethylene concentration in the head space in the odor bag was measured using a gas detector (manufactured by Gastec Co., Ltd.). The results are shown in Table 2.

As is clear from Table 2, the ethylene residual concentration of the decomposed materials of Examples 1 to 14 after 20 hours is lower than that of the powder catalyst of Comparative Examples 1 and 2. From this result, it can be seen that the decomposition material of the present invention decomposes ethylene efficiently and stably at 20 ° C. to −20 ° C. as compared with the powder catalyst.

[Odor component decomposition test]
Using the decomposition material obtained in Example 6, a decomposition test was conducted on formaldehyde, acetaldehyde, and trimethylamine as odor components. A formaldehyde decomposition test of the decomposition material and powder 1 obtained in Example 6 at 20 ° C. was performed. Paraformaldehyde was volatilized in the glove bag to prepare a gas (formaldehyde concentration 1000 ppm) in which formaldehyde and air were mixed. The gas was injected from the glove bag into the test bag (material: aluminum). In the same manner as in Example 1, a size having a mass of platinum-supported mesoporous silica of 0.8 g was cut out from a decomposed material having a thickness of 1 cm and a length × width of 25 cm × 25 cm. After allowing to stand at 20 ° C. for a predetermined time, the formaldehyde concentration in the head space in the test bag was measured by gas chromatography using a gas chromatograph (GC) (Shimadzu Corporation). The conditions for GC analysis are shown in Table 3. The column used was manufactured by Agilent. In Comparative Examples 3 to 5, 1.0 g of powder 1 was used by mass.

In the decomposition test of acetaldehyde, acetaldehyde was used as it was instead of paraformaldehyde, and acetaldehyde was volatilized in the glove bag to prepare a gas (acetaldehyde concentration 100 ppm) in which acetaldehyde and air were mixed. The GC analysis was performed under the same conditions.

In the triethylamine decomposition test, a toluene solution of triethylamine (about 8%) was used instead of paraformaldehyde, and triethylamine was volatilized in a globe bag to prepare a gas (triethylamine concentration 100 ppm) in which triethylamine and air were mixed. .. The GC analysis was performed under the same conditions.

The results of the decomposition tests of formaldehyde, acetaldehyde and triethylamine are shown in Table 4.

From the above results, it was found that the decomposing material of this example shows a remarkable decomposing effect on formaldehyde, acetaldehyde, and trimethylamine, which are typical volatile compounds, even at room temperature or lower. Since the catalyst weight of Example 6 is 0.8 g and the catalyst weight of Comparative Example 4 is 1.0 g, it is said that Example 6 has a higher catalytic activity per unit mass of catalyst than Comparative Example 4. I can guess.

The decomposition material according to the present invention can be applied to, for example, a filter of an air conditioner or an air purifier, and can decompose odorous substances in a room, ethylene or odorous substances in a warehouse, and the like. In addition, it can be applied to wallpaper, and can decompose indoor odorous substances, ethylene and odorous substances in warehouses, and the like. Furthermore, it can be applied to clothing and can decompose odorous substances generated from the body.

Claims (17)

A decomposition material having a base material and a coating film provided on the surface of the base material, and the coating film contains mesoporous silica on which particles containing a platinum group element are supported as a catalyst. The decomposition material according to claim 1, wherein the base material is any one of non-woven fabric, ceramic honeycomb, and paper honeycomb. The decomposition material according to claim 1 or 2, wherein the particles are platinum nanoparticles. The decomposition material according to any one of claims 1 to 3, further comprising a binder. The decomposition material according to claim 4, further comprising a sedimentation inhibitor. The decomposition material according to claim 4, wherein the binder is at least one of an inorganic binder and an organic binder. The decomposition material according to claim 5, wherein the sedimentation inhibitor is at least one of fumed silica and thixotropy. The decomposition material according to claim 6, wherein the inorganic binder is alumina. The decomposition material according to claim 5, wherein the coating film contains 5 to 95 parts by mass of fumed silica as the sedimentation inhibitor and 1 to 95 parts by mass of alumina as the binder with respect to 100 parts by mass of the mesoporous silica. .. The decomposition material according to claim 9, wherein the fumed silica is 5 to 80 parts by mass and the alumina is 1 to 80 parts by mass with respect to 100 parts by mass of the mesoporous silica. The decomposition material according to claim 4, further comprising a thixotropic agent. The eleventh claim, wherein the coating film contains 10 to 50 parts by mass of an organic binder as the binder and 10 parts by mass or less of the thiox agent as the binder with respect to 100 parts by mass of the mesoporous silica. Disassembled material. The decomposition material according to claim 6 or 12, wherein the organic binder is a polyester resin or an acrylic resin. The decomposition material according to claim 11 or 12, wherein the thixotropy is a maleic anhydride-based copolymer. The claim that 100 parts by mass of the mesoporous silica contains 10 to 50 parts by mass of a polyester resin or an acrylic resin as the organic binder, and 1 to 10 parts by mass of a maleic anhydride-based copolymer as the thixo agent. 12. The disintegrating material according to 12. The decomposition material according to any one of claims 1 to 15, which decomposes an odorous substance containing at least one volatile compound selected from aldehydes, fatty acids, sulfide compounds, and nitrogen compounds, and / or ethylene. .. An odorous substance containing the decomposing material according to any one of claims 1 to 15 and at least one volatile compound selected from aldehydes, fatty acids, sulfide compounds, and nitrogen compounds at low temperature, and / or A method for decomposing odorous substances and / or ethylene, which comprises contacting ethylene.