JP2014100638A - Method for manufacturing carbon monoxide purging filter, carbon monoxide purging filter, and carbon monoxide purging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a carbon monoxide purging filter in which a catalyst for purging carbon monoxide is fixed to a filter substrate while avoiding the congestion, mechanical damages, and thermal melting of the filter substrate and to provide the carbon monoxide purging filter thus obtained and a carbon monoxide purging apparatus using the same.SOLUTION: A carbon monoxide purging filter 10 in which gold catalyst nanoparticles are flocculated and adhered to the surface of a filter substrate 4 is manufactured by contacting and coating the filter substrate with a catalyst ink comprising: a gold nanoparticle catalyst 1 obtained by supporting gold nanoparticles 2 on inorganic particles 3; and a solvent for dispersing the gold nanoparticle catalyst and by subsequently drying and removing the solvent. It is desirable for the gold nanoparticle catalyst to abide in an ultimately deflocculated state within the catalyst ink and to be reflocculated atop the filter substrate 4. It is desirable, from the standpoint of adhesiveness, for the average particle diameter of the gold nanoparticle catalyst within the catalyst ink to be 5 μm or less. A carbon monoxide purging apparatus is provided by using such a carbon monoxide purging filter.

Description

  The present invention relates to a method for producing a carbon monoxide purification filter, a carbon monoxide purification filter, and a carbon monoxide purification device.

Carbon monoxide is an extremely toxic gas that can cause headaches, nausea and dizziness even at low concentrations. In a room, when using heating appliances such as oil stoves and gas stoves, water heaters, cooking appliances, etc., the concentration of carbon monoxide may increase unless attention is paid to ventilation.
Carbon monoxide is also generated by tobacco smoking. Tobacco smoke is also concerned about the health effects of passive smoking, and due to laws and regulations such as the Health Promotion Act, measures such as smoke smoking and smoking cessation have become mandatory in facilities and workplaces where many people gather. Yes.

  On the other hand, a gold nanoparticle catalyst capable of oxidizing carbon monoxide to carbon dioxide has been proposed as a kind of oxidation catalyst in relation to a technique applicable to carbon monoxide purification (Patent Document 1). Originally gold, which is a noble metal, is a very stable metal because of its poor reactivity. However, by making gold particles into ultrafine nanoparticles with a particle diameter of 10 nm or less, various catalytic activities are exhibited. Become. Therefore, in order to make it easy to use such gold nanoparticles, a gold nanoparticle catalyst has gold nanoparticles supported on inorganic particles having a particle diameter larger than that of the gold nanoparticles.

  When a carbon monoxide purification filter is to be manufactured using a gold nanoparticle catalyst, it is easier to use if the gold nanoparticle catalyst is fixed to a filter substrate. For example, a catalyst having a catalytic action can be manufactured by fixing catalyst particles of a gold nanoparticle catalyst on the surface of a filter substrate such as a nonwoven fabric.

 When fixing catalyst particles such as gold nanoparticle catalyst to a filter substrate such as a nonwoven fabric, if the catalyst particles are kneaded into a resin or applied using a binder, the surface of the catalyst particles becomes resin or By being covered with a binder or the like, the catalytic activity of the catalyst particles is hindered and reduced. In order to avoid this, a method of fixing the catalyst particles on the filter base material without using a binder has been developed.

For example, Patent Document 2 discloses a method in which a resin coating film is formed in advance on the surface of a filter base material to attach catalyst particles to the filter base material.
In Patent Document 3, a compressive force is applied to a system in which fibers and catalyst particles having a length of about 10 mm corresponding to a filter substrate and about 100 mm at the maximum are coexisting without a solvent by a high-speed stirring mill or the like by a dry method. A method of attaching catalyst particles to the surface of a filter substrate by applying mechanical energy such as stirring impact force, grinding force, and shearing force is disclosed.
In Patent Document 4, a thermoplastic resin is used as a filter substrate, catalyst particles having a melting point or decomposition temperature higher than the melting point thereof are heated to a temperature higher than the melting point of the thermoplastic resin, and an air flow including the heated catalyst particles is generated. A method is disclosed in which catalyst particles are attached to the surface of a filter substrate by spraying the surface of the filter substrate.

Japanese Patent No. 3-12934 JP 2009-61404 A JP 2008-179934 A Japanese Patent No. 4300006

However, in patent document 2, since the resin coating film is formed in order to provide the adhesiveness with respect to a catalyst particle on the surface of a filter base material, there exists a problem that a filter base material may be clogged. .
In Patent Document 3, a binder such as a resin is not used, but a mechanical load or impact is applied to the filter base material because the catalyst is attached to the filter base material using mechanical energy. There is a problem that the filter base material is easily damaged, and the catalyst particles cannot be adhered while maintaining the shape of the filter base material such as a 300 mm square shape because the filter base material is easily damaged.
In Patent Document 4, a thermoplastic resin is used for the filter base material, and the catalyst particles are attached to the filter base material by heating and melting to a temperature higher than the melting point thereof. There is a problem that temperature is required.

That is, the problem of the present invention is that when the catalyst particles are attached to the filter base material, the filter base material is not clogged or damaged, and a high temperature at which the filter base material melts is not required. It is providing the manufacturing method of a carbon purification filter.
Another object of the present invention is to provide a carbon monoxide purification filter in which catalyst particles adhere to a filter base material without depending on a binder or fusion.
Moreover, the subject of this invention is providing the carbon monoxide purification apparatus provided with the said carbon monoxide purification filter.

Therefore, in the present invention, a carbon monoxide purification filter manufacturing method, a carbon monoxide purification filter, and a carbon monoxide purification device having the following configurations are provided.
(1) A catalyst ink comprising a gold nanoparticle catalyst having gold nanoparticles supported on inorganic particles and a solvent in which the gold nanoparticle catalyst is dispersed,
After contacting the filter base material, the gold nanoparticle catalyst aggregated on the surface of the filter base material is attached by removing the solvent by drying.
A method for producing a carbon monoxide purification filter.
(2) The method for producing a carbon monoxide purification filter according to (1), wherein an average particle diameter of the gold nanoparticle catalyst in the catalyst ink is 5 μm or less.
(3) Carbon monoxide purification comprising a gold nanoparticle catalyst in which gold nanoparticles are supported on inorganic particles and a filter base material, wherein the gold nanoparticle catalyst is aggregated and adhered to the surface of the filter base material. filter.
(4) A carbon monoxide purification device comprising the carbon monoxide purification filter (3).

According to the carbon monoxide purification filter manufacturing method of the present invention, when the catalyst particles as the carbon monoxide oxidation catalyst are attached to the filter base material to form the carbon monoxide purification filter, the filter base material is clogged. It can be produced without causing damage and without the need for such high temperatures that the filter substrate melts.
According to the carbon monoxide purification filter of the present invention, the catalyst particles can be attached to the filter base material without depending on the binder or the fusion.
According to the carbon monoxide purification apparatus of the present invention, carbon monoxide can be purified by the carbon monoxide purification filter in which the catalyst particles are attached to the filter base material without depending on the binder or fusion.

The figure which illustrates typically an example of the carbon monoxide purification filter by this invention. The figure which shows an example of a gold nanoparticle catalyst typically. The enlarged photograph by the transmission electron microscope of an example of a gold nanoparticle catalyst. The enlarged photograph by the scanning electron microscope of one Embodiment of the carbon monoxide purification | cleaning filter by this invention. The figure which shows typically 1st Embodiment of the carbon monoxide purification apparatus by this invention. The figure which shows typically 2nd Embodiment of the carbon monoxide purification apparatus by this invention. The figure which shows typically 3rd Embodiment of the carbon monoxide purification apparatus by this invention. The enlarged photograph by the scanning electron microscope of the filter base material before making a gold nanoparticle catalyst adhere. The enlarged photograph by the scanning electron microscope of another embodiment of the carbon monoxide purification | cleaning filter by this invention.

    Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<< 1 >> Method for Producing Carbon Monoxide Purification Filter and Carbon Monoxide Purification Filter First, a method for producing a carbon monoxide purification filter and a carbon monoxide purification filter will be described.

  FIG. 1 is a diagram schematically illustrating a carbon monoxide purification filter 10 according to the present invention, FIG. 2 is a diagram schematically illustrating an example of a gold nanoparticle catalyst 1, and FIG. 3 is a gold nanoparticle. It is the enlarged photograph which image | photographed one example of the catalyst 1 with the transmission electron microscope. FIG. 4 is an enlarged photograph taken by a scanning electron microscope of one embodiment of the carbon monoxide purification filter according to the present invention.

In the method for producing a carbon monoxide purification filter according to the present invention, a catalyst ink comprising a gold nanoparticle catalyst having gold nanoparticles supported on inorganic particles and a solvent in which the gold nanoparticle catalyst is dispersed is brought into contact with the filter substrate. Thereafter, the method is a production method in which the agglomerated gold nanoparticle catalyst is attached to the surface of the filter substrate by removing the solvent by drying.
Thus, the carbon monoxide purification filter manufacturing method according to the present invention is a manufacturing method by a wet method using a solvent, whereas the conventional method using mechanical energy is a dry method.

  A carbon monoxide purification filter 10 according to the present invention includes a gold nanoparticle catalyst 1 in which gold nanoparticles 2 are supported on inorganic particles 3 and a filter base 4, and the gold nanoparticle catalyst 1 is on the surface of the filter base 4. The filter is agglomerated and adhered.

<< Gold nanoparticle catalyst 1 >>
The gold nanoparticle catalyst 1 is a catalyst formed by supporting gold nanoparticles 2 on inorganic particles 3. The gold nanoparticle catalyst 1 has a catalytic function as an oxidation catalyst that oxidizes carbon monoxide to carbon dioxide.
As shown in the schematic diagram of FIG. 2 and the enlarged photograph of FIG. 3, the gold nanoparticle catalyst 1 is formed by supporting gold nanoparticles 2 on the surface of the inorganic particles 3.

The catalytic function of oxidizing the carbon monoxide of the gold nanoparticle catalyst 1 to carbon dioxide does not require additional light or heat. For this reason, the gold nanoparticle catalyst does not require ultraviolet rays or visible light like a photocatalyst in order to exert its catalytic function, and does not require a high temperature of 150 ° C. or more like a platinum catalyst.
Therefore, the carbon monoxide purification filter 10 using the gold nanoparticle catalyst 1 can purify carbon monoxide even at room temperature without using a special light source or heat source. It can be used by attaching to a place. The normal temperature means 25 ° C. ± 15 ° C. according to JIS Z 8703.

[Gold nanoparticles 2]
The gold nanoparticle 2 is a gold nanoparticle having a particle size of nanometer order. The gold nanoparticle 2 becomes an active site of the gold nanoparticle catalyst 1.

The particle diameter of the gold nanoparticle 2 is an average particle diameter, preferably 1 to 20 nm, more preferably 1 to 5 nm. When the average particle diameter is within the above range, the bonding interface between the gold nanoparticles 2 and the inorganic particles 3 (so-called “perimeter”) while maintaining stable productivity of the gold nanoparticles 2. This is because, as a result, it is advantageous in terms of the efficiency and economical efficiency of the catalyst activity.
As the average particle diameter, for example, an average value calculated by measuring the particle diameter of the plurality of gold nanoparticles 2 supported on the gold nanoparticle catalyst 1 using a transmission electron microscope can be adopted.

[Inorganic particles 3]
The inorganic particles 3 are particles for supporting the gold nanoparticles 2. The inorganic particles 3 are substances capable of supporting the gold nanoparticles 2 and exhibiting the catalytic activity as the gold nanoparticle catalyst 1, and preferably a substance insoluble in the solvent of the catalyst ink described later. There is no particular limitation.

Examples of the inorganic particles 3 include inorganic oxide particles, inorganic material particles, and metal particles.
Examples of the inorganic oxide forming the inorganic oxide particles include aluminum oxide, titanium oxide, cupric oxide, zinc oxide, tin oxide, cerium oxide, yttrium oxide, bismuth oxide, iron oxide, cobalt oxide, and nickel oxide. And metal oxides such as zirconium oxide, silver oxide, manganese oxide, and magnesium oxide, and nonmetal oxides such as silicon oxide.
Examples of the inorganic substance forming the inorganic substance particles include clay minerals such as zeolite, bentonite, halloysite, and imogolite. In addition, as inorganic particles, composite material particles in which metal oxides such as iron oxide and nickel oxide are supported on clay minerals such as zeolite, composite material particles in which the surface of inorganic particles such as fumed silica is coated with organic substituents, etc. Also mentioned.
Examples of the metal forming the metal particles include iron, copper, and aluminum.
As the inorganic particles 3, particles of these substances may be used singly or in combination of a plurality of types.

  Among these, as the inorganic particles 3, those capable of supporting the gold nanoparticles 2 and effectively exhibiting the oxidation catalyst function for carbon monoxide include titanium oxide, cerium oxide, zirconium oxide, iron oxide, cobalt oxide, Nickel oxide and the like are preferable, and titanium oxide, cerium oxide, and zirconium oxide are more preferable. Furthermore, titanium oxide is preferable in terms of high catalytic activity when the gold nanoparticle catalyst 1 is formed as the inorganic particles 3 and excellent stability and economy. This is because high catalytic activity can be obtained without using a special heat source or light source and at room temperature even in a dark place such as the inside of an air purifier or an air conditioner.

  The particle shape of the inorganic particles 3 is not particularly limited, and examples thereof include a spherical shape, a spheroid shape, a polygonal shape, a scale shape, and other shapes.

The particle diameter of the inorganic particles 3 is not particularly limited as long as the gold nanoparticle catalyst 1 can be supported, but is 0.01 to 100 μm so that the particle diameter can be reduced by an inking operation described later. Is preferable, and it is more preferable that it is 0.01-10 micrometers. This is because if the particle diameter exceeds this range, the gold nanoparticle catalyst 1 may easily fall off from the filter substrate 4 when the gold nanoparticle catalyst 1 is formed. This is because if the particle diameter is less than this range, the surface area for supporting the gold nanoparticle catalyst 1 becomes too small, and the gold nanoparticles 2 cannot be fully supported.
The particle diameter of the inorganic particles 3 means the particle diameter of the aggregated particles when the inorganic particles 3 are aggregated. Incidentally, the inorganic particles 3 in the gold nanoparticle catalyst 1 shown in the enlarged photograph of the transmission electron microscope in FIG. 3 are aggregated particles.

If the particle diameter of the inorganic particles 3 is taken from the average particle diameter, the average particle diameter is not particularly limited, but is, for example, 0.1 to 30 μm. By making the average particle diameter of the inorganic particles 3 within this range, the gold nanoparticle catalyst 1 is excellent in productivity.
In addition, the value measured by the light-scattering particle size distribution measuring apparatus can be employ | adopted for the said particle diameter and average particle diameter, for example.

[Formation of gold nanoparticle catalyst 1]
As a method for forming the gold nanoparticle catalyst 1 by supporting the gold nanoparticles 2 on the surface of the inorganic particles 3, the following known formation methods can be employed. For example, a forming method such as a coprecipitation method (Japanese Patent No. 1623540) or a precipitation method (Japanese Patent Publication No. 6-29137 (Japanese Patent No. 1904258)) can be employed.

《Ink conversion》
In the inking operation, a catalyst ink in which the gold nanoparticle catalyst 1 is dispersed in a solvent is prepared. The catalyst ink according to the present invention is characterized in that the catalyst ink comprises a gold nanoparticle catalyst 1 in which gold nanoparticles 2 are supported on inorganic particles 3 and a solvent in which the gold nanoparticle catalyst 1 is dispersed. .
In a normal ink, when preparing an ink containing a solvent and a substance insoluble in the solvent, it is essential to include a dispersant and a binder. However, it is not necessary to use a dispersant or a binder in the catalyst ink according to the present invention. A catalyst ink can be prepared by dispersing the gold nanoparticle catalyst 1 in a solvent using only the gold nanoparticle catalyst 1 and the solvent that do not dissolve in the solvent.

  As a solvent used for inking, a solvent that does not dissolve the filter substrate 4 and the gold nanoparticle catalyst 1 is preferable. The reason why the filter substrate 4 and the gold nanoparticle catalyst 1 are dissolved is that when the dissolved material covers the surface of the gold nanoparticle catalyst 1, the catalytic activity may be lowered. There is no restriction | limiting in particular as a solvent which does not melt | dissolve the filter base material 4 and the gold nanoparticle catalyst 1. FIG. For example, alcohols such as ethanol and isopropanol, water, or a mixture of alcohol and water can be suitably used. In particular, it is preferable to use alcohol as the solvent in that the compatibility of the catalyst ink with the filter base material 4 can be improved.

  The concentration of the gold nanoparticle catalyst 1 in the catalyst ink is 0.1 to 30%, preferably 0.5 to 20%, by mass% of the gold nanoparticle catalyst 1 with respect to the total amount of the gold nanoparticle catalyst 1 and the solvent. More preferably, it is 1 to 15%. If the concentration is less than the above range, a sufficient amount of the gold nanoparticle catalyst 1 may not be attached to the filter substrate 4, and if the concentration exceeds the above range, the gold nanoparticle catalyst 1 is dispersed in the catalyst ink. This is because the stability may decrease.

When the gold nanoparticle catalyst 1 is agglomerated at the time of inking, it is preferable to release the agglomeration to make an ink. The gold nanoparticle catalyst 1 re-aggregated on the surface of the filter substrate 4 is more likely to be produced when the gold nanoparticle catalyst 1 is agglomerated and becomes finer than when the gold nanoparticle catalyst 1 is agglomerated. This is because the adhesion of the nanoparticle catalyst 1 to the filter substrate 4 can be enhanced. The reason is that, as can be imagined, the adhesion is enhanced in the process in which another gold nanoparticle catalyst 1 contacts and agglomerates with the gold nanoparticle catalyst 1 that has already contacted and adhered to the surface of the filter substrate 4, or It is presumed that the gold nanoparticle catalyst 1 aggregated to some extent in the process of approaching the surface of the filter base 4 is improved in adhesion when contacting the surface of the filter base 4. However, at present, the details of the mechanism of why the gold nanoparticle catalyst 1 aggregated on the surface of the filter substrate 4 has good adhesion to the filter substrate 4 are not known.
In the present invention, the adhesion means that the gold nanoparticle catalyst 1 is not easily detached from the filter base material 4 by an external force or the like, and can be said to be a fixing force of the gold nanoparticle catalyst 1 to the filter base material 4. .
The particle diameter of the gold nanoparticle catalyst 1 in the catalyst ink is preferably 10 μm or less, more preferably 5 μm or less, and even more preferably 3 μm or less, taking the average particle diameter including aggregated aggregated particles. When the average particle diameter exceeds the above range, the aggregated particles of the gold nanoparticles 2 adhering to the surface of the filter base 4 become too large, and the fixing force to the surface of the filter base 4 becomes weak, and adheres. This is because the properties may deteriorate.
The lower limit of the average particle diameter of the gold nanoparticle catalyst 1 is not particularly limited, but depends on the average particle diameter of the gold nanoparticles 2 and the inorganic particles 3 and is, for example, 0.1 μm.
As the average particle diameter, a median diameter can be adopted.
As the average particle diameter, for example, a value measured by a light scattering particle size distribution measuring apparatus can be adopted.

  To disaggregate the agglomerated gold nanoparticle catalyst 1 in the catalyst ink and make the gold nanoparticle catalyst 1 finer, for example, bead mill, sand mill, ball mill, pot mill attritor, paint mixer, etc. A miniaturization apparatus can be used. As media used for a bead mill or the like, zirconia beads or glass beads can be used.

  In the catalyst ink, as the gold nanoparticle catalyst 1 is agglomerated and further refined, the gold nanoparticle catalyst 1 is more likely to reaggregate on the surface of the filter substrate 4. Adhesion to 1 filter base material 4 can be improved.

  Generally, from the viewpoint of the dispersion stability of the gold nanoparticle catalyst 1 in the catalyst ink, it is preferable to use a dispersant such as a surfactant in the ink. In the present invention, however, the catalyst ink is brought into contact with the filter substrate 4 to remove the solvent and remove the solvent to adhere the gold nanoparticle catalyst 1, thereby further promoting the re-aggregation of the gold nanoparticle catalyst 1 to improve the adhesion. From the standpoint of enhancing, it is preferable not to use a dispersant such as a surfactant during ink production.

<< Contact of catalyst ink to filter substrate 4 >>
The catalyst ink can be brought into contact with the filter substrate 4 by a coating method.
After bringing the catalyst ink into contact with the filter substrate 4, the carbon monoxide purification filter 10 of the present invention can be obtained by drying and removing the solvent in the catalyst ink.
As described above, it is not preferable to use a dispersant or a binder in the catalyst ink in the present invention. If the dispersant or the binder is not used, the dispersed state of the ink changes to the dispersant or binder. It is unstable compared to the case where a dressing is used. For this reason, it is preferable to apply the catalyst ink to the filter substrate 4 immediately after the catalyst ink in which the gold nanoparticle catalyst 1 is dispersed.
Immediately refers to within 30 minutes, preferably within 15 minutes, more preferably within 10 minutes after preparing the catalyst ink.

  The coating method is not particularly limited, and a known coating method such as a dip coating method, a flow coating method, a comma knife method, a comma reverse method, a kiss coating method, or a gravure coating method can be employed. Or you may employ | adopt the method of apply | coating with dyeing machines, such as a zicker dyeing machine and a paddle dyeing machine, which are used in the dyeing field. It can be said that these dyeing machines are a kind of dip coat method.

  When the catalyst ink comes into contact with the filter substrate 4 and the solvent dries, the gold nanoparticle catalyst 1 in the catalyst ink aggregates on the surface of the filter substrate 4, whereby the gold nanoparticle catalyst 1 becomes a filter substrate. 4 adheres to the surface. The greater the degree of aggregation, the stronger the adhesion, and the gold nanoparticle catalyst 1 is less likely to drop off from the filter base material 4 and the adhesion can be enhanced. However, when the filter substrate 4 is made of fibers, the adhesiveness of aggregated particles having a diameter larger than the fiber diameter is rather reduced. Therefore, the degree of aggregation is preferably such that the particle diameter of the aggregated gold nanoparticle catalyst 1 is equal to or less than the fiber diameter of the filter substrate 4, and more preferably equal to or less than 50% of the fiber diameter.

Aggregation of the gold nanoparticle catalyst 1 is performed by concentrating the catalyst ink by drying and increasing the concentration of the gold nanoparticle catalyst 1. Therefore, the gold nanoparticle catalyst 1 can be fixed to the filter base 4 without requiring primer treatment on the filter base 4 or addition of a binder into the catalyst ink.
The re-aggregation of the gold nanoparticle catalyst 1 present in the catalyst ink occurs in any material of the filter base material 4 if the solvent is dried. Therefore, the filter base material 4 does not have a chemical structure for adsorbing the catalyst particles by ionic bonds. For example, in the present invention, the gold nanoparticle catalyst 1 can be adhered to the filter base 4 made of polyolefin fiber such as polyethylene or polypropylene.

  At the time of inking, since only the solvent is used in addition to the gold nanoparticle catalyst 1, and the solvent used for the catalyst ink is lost by drying, it is applied to the surface of the filter substrate 4 after coating and drying. The gold nanoparticle catalyst 1 adhered and fixed is completely exposed except for the contact surface with the filter substrate 4 without being covered with a resin, a binder, a silane coupling agent or the like. For this reason, the carbon monoxide purification filter 10 manufactured in this way has no factor that inhibits the expression of the catalytic activity on the surface of the gold nanoparticle catalyst 1. Therefore, this carbon monoxide purification filter 10 can effectively exhibit the catalytic activity of the gold nanoparticle catalyst 1.

<Filter substrate>
The filter substrate 4 is not particularly limited as long as it has air permeability. The fact that the filter base 4 has air permeability means that the filter base 4 is a material having a three-dimensional network structure.
Specifically, for example, woven fabric, knitted fabric, paper, non-woven fabric, net-like body, porous body or the like can be used as the filter base 4. Among these, the nonwoven fabric is preferable as the filter base material 4 because it is excellent in air permeability.

  The material of the filter substrate 4 is not particularly limited. As long as the filter base material 4 that is insoluble in the solvent used for the catalyst ink is used, the filter base material 4 can be selected without any limitation due to the melting point of the material such as fibers constituting the filter base material 4. The filter base 4 does not necessarily need to be heat-meltable, and a material that is not heat-meltable can also be used. Alternatively, the filter base 4 having heat-meltability may be used.

As a material of the filter base material 4, for example, when the filter base material 4 is formed of a nonwoven fabric, the material of the nonwoven fabric fiber includes an inorganic fiber using an inorganic substance and an organic fiber using a polymer. As the inorganic fiber, glass fiber, carbon fiber, metal fiber, or the like can be used. As the organic fibers, polyolefin fibers such as polyethylene and polypropylene, polyester fibers such as polyethylene terephthalate and polyethylene naphthalate, polyamide fibers such as nylon (registered trademark), and the like can be used. These fibers may be used alone or in combination of a plurality of types.
Among these non-woven fabrics using these fibers, organic fibers, organic fibers using synthetic polymers, in other words, non-woven fabrics using synthetic fibers, are preferred because they are economical.

The filter substrate 4 is preferably wettable with respect to the solvent of the catalyst ink. This is because if there is no wettability, the catalyst ink may not uniformly contact the surface of the filter substrate 4 when the catalyst ink is applied.
The filter substrate 4 is preferably insoluble in the solvent of the catalyst ink. This is to prevent the dissolved components of the filter base material 4 from covering the surface of the gold nanoparticle catalyst 1.

  When using what is formed from fibers, such as a nonwoven fabric, as the filter base material 4, although the fiber diameter of the fiber is not specifically limited, For example, it is 5-30 micrometers. It is because it becomes easy to make air permeability and practical strength compatible when the fiber diameter is within this range.

  The shape and thickness of the filter substrate 4 are not particularly limited, and are appropriately selected according to the application. For example, the filter substrate 4 has a columnar shape, a sheet or a plate shape. In the case of a columnar shape, the carbon monoxide purification filter 10 is suitably applied to an application disposed inside a cylindrical pipe. In the case of a sheet or plate, the carbon monoxide purification filter 10 is, for example, planar. The present invention is suitably applied to applications that are arranged in the opened intake port or blower port portion.

Although the porosity of the filter base material 4 is not specifically limited, For example, it is preferable that it is 50 to 90%. This is because when the porosity is within this range, it is easy to achieve both practical air permeability and practical strength as the carbon monoxide purification filter 10. Such a porosity can be easily realized by a nonwoven fabric.
The porosity is measured by measuring the total volume of fibers constituting the filter base 4 and the volume of the filter base 4 in the case where the filter base 4 uses fibers, and {1- (filter The total volume of fibers constituting the substrate 4 / volume of the filter substrate 4)} × 100.

<< Effects of carbon monoxide purification filter manufacturing method >>
In the method for producing a carbon monoxide purification filter according to the present invention as described above, the catalyst particles of the gold nanoparticle catalyst 1 which is an oxidation catalyst for carbon monoxide are attached to the filter base 4 to form the carbon monoxide purification filter 10 and In doing so, the filter base material 4 can be produced without clogging or damage, and without requiring a high temperature at which the filter base material melts.

That is, in the production method of the present invention, the step of preparing the carbon monoxide purification filter 10 by attaching the gold nanoparticle catalyst 1 to the filter base 4 is brought into contact with the filter base 4 by applying a catalyst ink or the like. Since only the step of drying can be performed, it is possible to avoid applying a mechanical load to the filter substrate 4 as when using conventional mechanical energy. Therefore, as long as the filter base 4 insoluble in the solvent used for the catalyst ink is used, the filter base 4 is not damaged.
And since the gold nanoparticle catalyst 1 can be made to adhere to the filter base material 4 irrespective of the heat melting and binder of the filter base material 4, the filter base material 4 is not clogged.
Further, since the gold nanoparticle catalyst 1 can be attached to the filter base material 4 without depending on the heat melting of the filter base material 4, the inorganic base material 3 constituting the gold nanoparticle catalyst 1 includes the filter base material 4. Since a material having a lower melting point can also be used, the degree of freedom in material design can be increased.

In addition, since the fine gold nanoparticle catalyst 1 in the catalyst ink becomes an agglomerated gold nanoparticle catalyst 1 and is adhered and fixed to the filter substrate 4, the binder component adhered to the surface of the catalyst particles For example, a gold nanoparticle catalyst 1 that is not a particle that exhibits an adhesive force when a part of the particle is dissolved in a solvent can be used.
Further, the gold nanoparticle catalyst 1 can be attached to the filter base material 4 without depending on the heat melting or the binder of the filter base material 4, and the gold nanoparticle catalyst 1 attached to the filter base material 4 Since the surface can be prevented from being covered with a binder or the like, the surface of the gold nanoparticle catalyst 1 is covered with the binder or the like so that the catalytic activity does not decrease, and the catalytic activity is effectively exhibited. be able to.

<< Effects as carbon monoxide purification filter 10 >>
The carbon monoxide purification filter 10 according to the present invention that can be obtained by the manufacturing method as described above can have the catalyst particles attached to the filter base material without depending on the binder or fusion. Therefore, the catalytic activity of the gold nanoparticle catalyst 1 can be effectively exhibited. Moreover, the catalytic activity can be exhibited at room temperature or in a dark place.

<< 2 >> Carbon Monoxide Purification Device A carbon monoxide purification device according to the present invention includes the carbon monoxide purification filter described above, and is a purification device that can be purified by oxidizing carbon monoxide.

<< First Embodiment >>
FIG. 5 shows a basic configuration example as the first embodiment of the carbon monoxide purifier according to the present invention. A carbon monoxide purification apparatus 100 shown in the figure includes a main body 51, an intake port 52 provided in the main body 51, and carbon monoxide that is provided on the downstream side of the intake port 52 and purifies air taken in from the intake port 52. The purification filter 10, the fan 53 that is provided on the downstream side of the carbon monoxide purification filter 10 and sucks air from the intake port 52, and the air that is provided on the downstream side of the fan 53 and purified by the carbon monoxide purification filter 10. And an air outlet 54 provided in the main body 51 to be blown out.

  In the carbon monoxide purification device 100 shown in FIG. 5, the carbon monoxide purification filter 10 is the carbon monoxide purification filter 10 according to the present invention described above. Other components such as the main body 51 and the fan 53 can be appropriately selected from those known in the conventional air purifying apparatus according to the application.

  The carbon monoxide purification apparatus 100 takes in the contaminated air Ad contaminated with carbon monoxide from the intake port 52 by the fan 53 and purifies it by the carbon monoxide purification filter 10. Purified air Ac purified from carbon is blown out.

  By using the carbon monoxide purification device 100 having such a configuration, the oxidation catalyst action of the carbon monoxide purification filter 10 to which the catalyst particles are attached without depending on the binder or fusion is used at room temperature in the air. By oxidizing carbon monoxide to carbon dioxide, it becomes possible to purify carbon monoxide, which is extremely toxic compared to carbon dioxide.

<< Second Embodiment >>
FIG. 6 shows a second embodiment of the carbon monoxide purification apparatus according to the present invention. The present embodiment is a form example in which the constituent elements are shown more specifically than the first embodiment.
A carbon monoxide purification device 100 shown in the figure is a configuration example of a front intake top surface blowing type device that sucks air from the front surface of the side surface and blows air from the top surface.

The carbon monoxide purification apparatus 100 shown in the figure includes a main body 51, an intake port 52 provided on the front side of the side surface of the main unit 51, an intake port louver 52r provided in the intake port 52,
A dust collection filter 55 provided on the downstream side of the intake port 52 for purifying dust in the air sucked from the intake port 52; a dust collection filter fixing frame 55a for fixing the dust collection filter 55;
A deodorizing filter 56 provided on the downstream side of the dust collecting filter 55 for purifying odors in the air after passing through the dust collecting filter 55; a deodorizing filter fixing frame 56a for fixing the deodorizing filter 56;
A carbon monoxide purification filter 10 provided on the downstream side of the deodorization filter 56 for purifying carbon monoxide in the air after passing through the deodorization filter 56; a carbon monoxide purification filter fixing frame 57a for fixing the carbon monoxide purification filter 10; ,
A fan 53 that is provided on the downstream side of the carbon monoxide purification filter 10 and sucks air from the intake port 52 and passes through each filter; a motor 53m that drives the fan 53;
An air outlet 54 provided on the upper surface of the main body 51 on the downstream side of the fan 53 and blowing out purified air; an air outlet louver 54r provided in the air outlet 54;
A control unit 58 for controlling the operation of the device, such as the driving of the fan, the air volume, and the driving time, and a control panel 58p provided in the control unit 58 for designating the operation status;
And a foot 59 for supporting the main body.
The fan 53 is a propeller fan in this embodiment.

  Each component added to the first embodiment, for example, a dust collection filter 55, a deodorizing filter 56, a control unit 58, and the like may be appropriately selected from known air purification devices according to the application. it can.

  Also in the carbon monoxide purification apparatus 100 in the present embodiment, as in the first embodiment, the carbon monoxide in the air is oxidized by the oxidation catalytic action of the carbon monoxide purification filter 10 to oxidize carbon dioxide in the air. By doing so, it becomes possible to purify carbon monoxide, which is extremely toxic compared to carbon dioxide.

  Furthermore, the carbon monoxide purification apparatus 100 according to the present embodiment purifies dust in the air with the dust collection filter 55 before purifying the air with the carbon monoxide purification filter 10, and thereafter, with the deodorization filter 56. Odor is purified, and components to be purified other than carbon monoxide can be removed in front of the carbon monoxide purification filter 10 as much as possible. For this reason, it becomes possible to prevent the carbon monoxide purification filter 10 from being contaminated by dust and odor components and shortening the life of the carbon monoxide purification filter 10.

<< Third Embodiment >>
FIG. 7 shows a third embodiment of the carbon monoxide purification apparatus according to the present invention. In the present embodiment, like the second embodiment, the constituent elements of the first embodiment are shown more specifically than the first embodiment.
A carbon monoxide purification apparatus 100 shown in the figure is a configuration example of a bottom intake front blower type apparatus that sucks air from the lower surface of the apparatus and blows air from the front surface of a side surface.

The carbon monoxide purification apparatus 100 shown in the figure includes a main body 51, an intake port 52 provided on the lower surface side of the main unit 51, an intake port louver 52r provided in the intake port 52,
A dust collection filter 55 provided on the downstream side of the intake port 52 for purifying dust in the air sucked from the intake port 52; a dust collection filter fixing frame 55a for fixing the dust collection filter 55;
A deodorizing filter 56 provided on the downstream side of the dust collecting filter 55 for purifying odors in the air after passing through the dust collecting filter 55; a deodorizing filter fixing frame 56a for fixing the deodorizing filter 56;
A carbon monoxide purification filter 10 provided on the downstream side of the deodorization filter 56 for purifying carbon monoxide in the air after passing through the deodorization filter 56; a carbon monoxide purification filter fixing frame 57a for fixing the carbon monoxide purification filter 10; ,
A fan 53 that is provided on the downstream side of the carbon monoxide purification filter 10 and sucks air from the intake port 52 and passes through each filter; a motor 53m that drives the fan 53;
A blower port 54 that blows out purified air that is provided on the downstream side of the fan 53 on the front surface of the side surface of the main body 51; a blower port louver 54r that is provided in the blower port 54;
A control unit 58 for controlling the operation of the device, such as the driving of the fan, the air volume, and the driving time, and a control panel 58p provided in the control unit 58 for designating the operation status
And a foot 59 for supporting the main body.
The fan 53 is a sirocco fan in this embodiment.
The foot 59 is configured such that air is sucked into the air inlet 52 from the gap between the feet 59.

Also in the carbon monoxide purification apparatus 100 in the present embodiment, as in the first embodiment, the carbon monoxide in the air is oxidized by the oxidation catalytic action of the carbon monoxide purification filter 10 to oxidize carbon dioxide in the air. By doing so, it becomes possible to purify carbon monoxide, which is extremely toxic compared to carbon dioxide.

  Further, the carbon monoxide purification apparatus 100 in the present embodiment also purifies dust in the air with the dust collection filter 55 before purifying the air with the carbon monoxide purification filter 10, and thereafter, with the deodorization filter 56. Odor is purified, and components to be purified other than carbon monoxide can be removed in front of the carbon monoxide purification filter 10 as much as possible. For this reason, it becomes possible to prevent the carbon monoxide purification filter 10 from being contaminated by dust and odor components and shortening the life of the carbon monoxide purification filter 10.

<< 3 >> Applications Applications of the carbon monoxide purification filter 10 according to the present invention can be widely used for applications for purifying carbon monoxide in various situations. For example, a carbon monoxide purification filter is suitably used as an air purification filter for an air purifier, an air conditioner, a smoke distributor, or the like in a vehicle, a vehicle, a vehicle, or a vehicle. obtain.
The carbon monoxide purification apparatus 100 according to the present invention can be suitably used, for example, as the air conditioner.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

[Example 1]
(Preparation of gold nanoparticle catalyst 1)
As the gold nanoparticle catalyst 1, gold nanoparticle 2 supported on inorganic particles 3 of titanium oxide particles was prepared by using titanium oxide particles (Nippon Aerosil Co., Ltd., AEROXIDE (registered trademark) TiO ₂ P25, average primary particle diameter of about 21 nm). And a specific surface area of 50 ± 15 m ² / g, an average particle diameter of 4 μm) and tetrachloroauric acid were synthesized by a precipitation method (see Japanese Patent Publication No. 6-29137 (Patent No. 1904258)).
The average particle diameter is a median diameter measured using ion-exchanged water as a dispersion medium with a laser diffraction / scattering particle size distribution analyzer (LA-920, manufactured by Horiba, Ltd.).

(Inking: Preparation of catalyst ink)
0.12 g of the gold nanoparticle catalyst 1 was weighed into a 20 ml sample tube. Next, absolute ethanol having a weight 19 times the weight of the weighed gold nanoparticle catalyst 1 was added as a solvent, so that the solid concentration was 5 wt%. Then, 4.0 g of zirconia beads having a diameter of 1.0 mm was added and shaken for 15 minutes to prepare a dispersion liquid in which the gold nanoparticle catalyst 1 was dispersed in ethanol. The zirconia beads in this dispersion were settled and removed to prepare a catalyst ink.

(Coating: filter production)
The catalyst ink prepared above was applied to the filter substrate 4 immediately after dispersion. As the filter substrate 4, a polypropylene nonwoven fabric (manufactured by Asahi Kasei Fibers Co., Ltd., Ertask Limp (registered trademark) PC8045, weight per unit area: 45 g / m ² ) produced by a spunbond method and a thermal bond method was used. Application of the catalyst ink to the filter base material 4 is performed by placing the filter base material 4 cut to about 10 cm square on a glass substrate, sprinkling the catalyst ink just after dispersion evenly with a dropper, and then applying it on a hot plate at 110 ° C. The carbon monoxide purification filter 10 was obtained by drying the whole glass substrate for 10 minutes and removing the solvent.

FIG. 4 shows an enlarged photograph of the obtained carbon monoxide purification filter 10 observed with a scanning electron microscope (SEM). FIG. 8 shows an enlarged photograph of the filter base 4 before application of the catalyst ink, observed under the same conditions.
As shown in FIG. 4, the aggregated gold nanoparticle catalyst 1 particles are fixed to the filter base material 4 in a state where the non-woven fiber surface of the filter base material 4 is substantially uniformly attached. confirmed. Moreover, it turns out that the filter base material 4 has a flat cross section and a fiber diameter of about 40 μm.

[Example 2]
(Gold nanoparticle catalyst 1)
The gold nanoparticle catalyst 1 used in Example 1 was used.

(Inking: Preparation of catalyst ink)
0.12 g of the gold nanoparticle catalyst 1 was weighed into a 20 ml sample tube. Next, absolute ethanol having a weight 19 times the weight of the weighed gold nanoparticle catalyst 1 was added as a solvent, so that the solid concentration was 5 wt%. A stir bar was introduced therein and stirred for 15 minutes using a magnetic stirrer to prepare a catalyst ink in which the gold nanoparticle catalyst 1 was dispersed in ethanol.

(Coating: filter production)
The catalyst ink prepared above was applied to the filter substrate 4 immediately after dispersion. Application and subsequent drying were performed in the same manner as in Example 1 to obtain a carbon monoxide purification filter 10.

FIG. 9 shows an enlarged photograph of the obtained carbon monoxide purification filter 10 observed with a scanning electron microscope (SEM). As shown in FIG. 9, the observation magnification is different from that of the enlarged photograph of Example 1 shown in FIG.
As shown in FIG. 9, in the carbon monoxide purification filter 10, the gold nanoparticle catalyst 1 aggregated in a larger mass than that in Example 1 is formed between the fibers of the nonwoven fabric of the filter base 4. In addition, it was confirmed that there was something adhering to the filter substrate 4 in a tangled state.

  The reason why the size of the agglomerated particles of the gold nanoparticle catalyst 1 adhering to the filter substrate 4 is larger than that of Example 1 is that the dispersion force at the time of preparing the catalyst ink is weak, so This is because the gold nanoparticle catalyst 1 is weakly dispersed and has a large aggregation state. This is because the highly aggregated gold nanoparticle catalyst 1 is adhered to the filter substrate 4 as it is or agglomerated again to form larger particles.

[Performance evaluation]
About the carbon monoxide purification filter 10 obtained above, carbon monoxide purification performance and adhesion of the gold nanoparticle catalyst 1 were evaluated.

(Evaluation of carbon monoxide purification performance)
Synthetic air in which nitrogen and oxygen are mixed at the same ratio as the atmosphere and carbon monoxide at a concentration of 800 ppm is mixed with carbon monoxide purification filter 10 fixed to a jig at a room temperature of 23 ° C. per area per hour. The flow rate was 1 cm ³ / (min · cm ² ), and the conversion rate from carbon monoxide to carbon dioxide was determined by measuring the decrease amount of carbon monoxide and the increase amount of carbon dioxide after aeration.
As a result, in both Example 1 and Example 2, the conversion rate was 0.09, and it was confirmed that the carbon monoxide was capable of purifying by oxidation removal.
The said conversion rate is the value computed with the following formula from the density | concentration [ppm] before ventilation | gas_flowing, and the density | concentration [ppm] after ventilation | gas_flowing with respect to carbon monoxide.
Conversion rate = (concentration before ventilation-concentration after ventilation) / concentration before ventilation

(Evaluation of adhesion)
The adhesion property of the gold nanoparticle catalyst 1 to the filter base 4 is determined by the number of dropped particles of the gold nanoparticle catalyst 1 dropped on the surface of the glass substrate by lightly shaking the carbon monoxide purification filter 10 on a clean glass substrate. Was evaluated by counting.
As a result, 100 or more shed particles were confirmed in Example 2, whereas no shed particles were confirmed in Example 1.

(Summary of evaluation)
In the carbon monoxide purification filter 10 of Example 1, the gold nanoparticle catalyst 1 was well attached to the filter base 4. On the other hand, compared with Example 1, the carbon monoxide purification filter of Example 2 was found to have fallen particles and poor adhesion.
However, the purification performance of carbon monoxide was the same in both Example 1 and Example 2.
For this reason, in Example 2, the filter front and back are sandwiched with a filter base 4 such as a nonwoven fabric or a porous material for protection so that an external force that causes the gold nanoparticle catalyst 1 to fall off is not applied. If it uses, it will be judged that the purification performance similar to Example 1 can be maintained.

  In addition, the reason why Example 1 has better adhesion than Example 2 is that the gold nanoparticle catalyst 1 is more well dispersed and reduced in agglomeration to reduce the size of the filter base when inking. The tendency of reaggregation on the surface of the material 4 is increased, and the particle diameter of the aggregated gold nanoparticle catalyst 1 can be made smaller than the fiber diameter of the nonwoven fabric of the filter base material 4. It is judged that this is because it becomes easier to carry the.

DESCRIPTION OF SYMBOLS 1 Gold nanoparticle catalyst 2 Gold nanoparticle 3 Inorganic particle 4 Filter base material 10 Carbon monoxide purification filter 51 Main body 52 Inlet 52r Inlet louver 53 Fan 53m Motor 54 Air outlet 54r Air outlet louver 55 Dust collection filter 55a Dust collection filter Fixed frame 56 Deodorizing filter 56a Deodorizing filter fixing frame 57a Carbon monoxide purification filter fixing frame 58 Control unit 58p Control panel 59 Foot 100 Carbon monoxide purification device Ac Purified air Ad Contaminated air

Claims (4)

A catalyst ink comprising a gold nanoparticle catalyst having gold nanoparticles supported on inorganic particles, and a solvent in which the gold nanoparticle catalyst is dispersed,
After contacting the filter base material, the gold nanoparticle catalyst aggregated on the surface of the filter base material is attached by removing the solvent by drying.
A method for producing a carbon monoxide purification filter.   The manufacturing method of the carbon monoxide purification filter of Claim 1 whose average particle diameter of the gold nanoparticle catalyst in the said catalyst ink is 5 micrometers or less.   A carbon monoxide purification filter comprising a gold nanoparticle catalyst in which gold nanoparticles are supported on inorganic particles and a filter base material, wherein the gold nanoparticle catalyst is aggregated and adhered to the surface of the filter base material.   A carbon monoxide purification device comprising the carbon monoxide purification filter according to claim 3.