JP6202539B2 - Carbon dioxide generation system and liquid cartridge mounted on it - Google Patents

Description

  The present invention relates to a carbon dioxide generation system that supplies a liquid containing organic molecules that generate carbon dioxide by photocatalysis to a support on which a photocatalyst is supported. And a liquid cartridge mounted on the carbon dioxide generation system.

  Photocatalysts that exhibit catalytic action by irradiation with actinic rays such as ultraviolet light and visible light are used as air purification materials that remove harmful substances, deodorizing materials that decompose bad odors, and water purification materials that decompose and remove organic compounds dissolved in water. ing. In addition, it is applied as an antibacterial material using the oxidation action of a photocatalyst, and as an antifouling material that prevents dirt on window glass and outer walls. Furthermore, the application to the use for attracting mosquitoes, the use to inactivate allergens such as pollen, and the use for promoting growth to plants have been proposed.

  Patent Document 1 proposes a blood-sucking mosquito trapping device having an attracting lamp that emits ultraviolet rays, and an attachment frame that is attached with an adhesive sheet for capturing attracted flying insects and holds a photocatalyst. The organic compound floating in the air is decomposed into carbon dioxide by the oxidizing action of the photocatalyst, and blood-sucking mosquitoes are attracted by the carbon dioxide and captured by the adhesive sheet. Patent Document 2 proposes a multi-functional mosquito collector having the following configuration as a method for attracting mosquitoes. In other words, 1) attracts mosquitoes at the wavelength of near-ultraviolet light, and 2) fills the inside of the body with an attractant of an acidic liquid, and the temperature inside the body is raised by irradiation with an ultraviolet LED lamp, imitating human body odor 3) A device is proposed that attracts mosquitoes by facilitating the generation of odors, 3) Titanium oxide is provided inside the main body, removes off-flavors generated by lightning mosquitoes, and decomposes organic substances in the air into carbon dioxide and water. ing.

  Patent Document 3 proposes a culture apparatus for culturing plants, microorganisms, and the like using at least a nutrient solution in a state isolated from soil. Specifically, the outer surface of the fabric fibers constituting the purification filter is coated with a photocatalyst, and harmful microorganisms and other contaminants contained in the solution are decomposed and removed by the photocatalytic purification action, so that the nutrient solution is in good condition. It is described that the growth of the plant can be promoted by carbon dioxide generated by the purifying action as well as maintaining. In Patent Document 4, a visible light responsive photocatalyst is fixed to a carpet surface with a binder resin with the object of efficiently deactivating allergens such as pollen attached to the carpet surface and decomposing it into water and carbon dioxide. A method has been proposed.

JP 2006-87371 A JP 2013-39080 A JP 2011-24462 A JP 2008-237793 A

  According to the methods of Patent Documents 1 and 2, since organic substances floating in the air are decomposed with a photocatalyst to generate carbon dioxide, there is a merit that the apparatus can be miniaturized. There was a problem that the effect of attracting mosquitoes was low because the amount was not sufficient to attract them. Moreover, according to the method of Patent Document 3, there is an advantage that the nutrient solution can be purified, but the amount of carbon dioxide generated is not a sufficient amount, and stable carbon dioxide supply cannot be desired. As a method for supplying stable carbon dioxide, there is a method for supplying carbon dioxide by providing a cylinder facility, but there is a problem that the replacement work is costly.

  The present invention has been made in view of the above background, and an object thereof is to provide a carbon dioxide generating system capable of generating carbon dioxide with high efficiency with a simple system.

As a result of extensive studies by the present inventors, it has been found that the problems of the present invention can be solved in the following modes, and the present invention has been completed.
[1]: A photocatalyst, a carrier for immobilizing the photocatalyst, and a liquid supply means for supplying the photocatalyst with a liquid containing organic molecules that are decomposed by the photocatalytic action of the photocatalyst to generate carbon dioxide. The organic molecule is contained in an amount of 2 parts by mass or more with respect to 100 parts by mass of the liquid, and carbon dioxide is continuously generated by repeatedly supplying the liquid to the carrier and consuming the liquid in the carrier. Carbon dioxide generation system to generate.
[2]: The carbon dioxide according to [1], further comprising a carbon dioxide retention space in which the carbon dioxide is retained, and a discharge port that releases the carbon dioxide in the carbon dioxide retention space at a concentration of 600 ppm or more. Generating system.
[3]: The carbon dioxide generating system according to [1] or [2], wherein the carrier is made of a porous body, and the photocatalyst is also carried on a porous portion inside the carrier.
[4]: The carbon dioxide generating system according to any one of [1] to [3], wherein the carrier is a porous thin film.
[5]: The photocatalyst is a metal oxide semiconductor containing at least one selected from TiO ₂ , ZnO, SrTiO ₃ , SnO ₂ and WO ₃ which may have a cocatalyst, The carbon dioxide generating system according to any one of [1] to [4], which is a substance containing at least one of Pt, Pd, Cu (II), Fe (III), Au, Ag, Ru, and Ni.
[6] The carbon dioxide generating system according to any one of [1] to [5], wherein the liquid includes water and an organic solvent compatible with the water.
[7]: The carbon dioxide generating system according to any one of [1] to [6] used for capturing mosquitoes.
[8] The carbon dioxide generating system according to any one of [1] to [6], which is used for promoting plant growth.
[9]: The carbon dioxide generating system according to [7], further comprising an odorous material preferred by mosquitoes.
[10] The carbon dioxide generation system according to any one of [1] to [9], further including a light source capable of exciting the photocatalyst.
[11]: The carbon dioxide generation system according to any one of [1] to [10], further including a heat source.
[12]: A liquid cartridge mounted on the carbon dioxide generation system according to any one of claims 1 to 11, wherein the carbon dioxide generation system includes a photocatalyst and a carrier for fixing the photocatalyst. Liquid supply means for supplying the photocatalyst with a liquid containing organic molecules that generate carbon dioxide by being decomposed by the photocatalytic action of the photocatalyst, storing the liquid, and via the liquid supply means A liquid cartridge configured to be able to supply the liquid to the carrier, and further configured to be detachable from the carbon dioxide generation system.

  According to the present invention, it is possible to provide a carbon dioxide generation system capable of generating carbon dioxide with high efficiency with a simple system.

The schematic diagram which shows an example of the carbon dioxide generation system which concerns on 1st Embodiment. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1. The schematic diagram for demonstrating the support body which concerns on 1st Embodiment, and the photocatalyst supported by this. The schematic diagram for demonstrating the support body which concerns on 1st Embodiment, the photocatalyst supported by this, and the supplied organic molecule. The schematic diagram for demonstrating the support body which concerns on 2nd Embodiment, and the photocatalyst supported by this, and the supplied organic molecule | numerator. The schematic diagram which shows an example of the carbon dioxide generation system which concerns on a 1st modification. The schematic diagram which shows an example of the carbon dioxide generation system which concerns on a 2nd modification. The schematic diagram which shows an example of the carbon dioxide generation system which concerns on a 3rd modification. The schematic diagram which shows an example of the carbon dioxide generation system which concerns on 3rd Embodiment. Absorption spectrum, and graph plotting the number of photons that can be used in the reaction with respect to the wavelength of TiO ₂ and WO _3. The figure which plotted the carbon dioxide production speed with respect to the frequency | count of screen printing in an Example. In the Example, the figure which plotted the carbon dioxide production speed | rate after supplying 0.4 cc of liquid per 100 cm < ² > of support body surface areas.

  The carbon dioxide generation system according to the present invention includes a photocatalyst, a carrier that immobilizes the photocatalyst, a liquid that contains organic molecules that are decomposed by the photocatalytic action of the photocatalyst to generate carbon dioxide, and a carrier that carries the photocatalyst. The present invention relates to a system that includes liquid supply means for supplying a liquid, and continuously generates carbon dioxide by repeatedly supplying the liquid to the carrier and consuming the liquid on the carrier. That is, an organic molecule that decomposes to generate carbon dioxide is supplied in a liquid medium, and the organic molecule is consumed by the photocatalytic action of the photocatalyst supported on the carrier, that is, a liquid supply-consumption cycle. By repeating, carbon dioxide is continuously generated. Here, “repetition” includes not only the case of supplying the liquid at a predetermined time interval but also the aspect of supplying the liquid at a desired timing and the aspect of supplying the liquid continuously. Further, “consumption” means that a liquid component is decomposed and vaporized by a redox reaction. Further, the consumption may include a mode in which the state is changed by the vaporization of the liquid and the liquid is consumed. In addition, “supported” is only required to be fixed to the support, and examples thereof include an embodiment in which the support is kneaded and an attached state.

  In this invention, the organic molecule which decomposes | disassembles by the photocatalytic action of a photocatalyst and generate | occur | produces a carbon dioxide is included at least 2 mass parts or more with respect to 100 mass parts of liquids. The organic molecule may be solid or liquid, and all liquid components may be composed of the organic molecule. When the organic molecule is solid, it is dissolved or dispersed in the liquid. From the viewpoint of penetrating into the support and increasing the surface area, an embodiment in which the organic molecule is dissolved is preferable. The actinic ray includes the entire band of light that exhibits activity with respect to the photocatalyst, and any wavelength can be used for the carbon dioxide generating system of the present invention as long as it is within this band.

  Although the kind of liquid is not specifically limited, It is preferable to contain the organic solvent which shows compatibility with water and water. By including an organic solvent that is compatible with water, the evaporation rate of the liquid can be promoted, and the wettability to the carrier can be improved. Further, the surface tension or capillary suction force on the carrier can be increased. Although it does not specifically limit as an example of the organic solvent compatible with water, Ethyl alcohol, methyl alcohol, propyl alcohol, etc. can be illustrated. Ethyl alcohol is particularly preferable from the viewpoint of safety and price. The organic solvent itself is also included in the classification of organic molecules, and the organic solvent can be decomposed by photocatalysis to generate carbon dioxide. However, when the evaporation of the organic solvent itself is more dominant than the decomposition by photocatalysis, that is, the organic solvent in which the number of molecules to be decomposed by photocatalysis <the number of molecules to be evaporated is referred to as “organic molecule” in the present specification. Not included.

  The carbon dioxide generating system according to the present invention can be applied to general uses in which carbon dioxide is generated by irradiation with actinic rays, such as mosquito collection, plant growth promotion, and microorganism culture. In addition, the size and ratio of each member in the following drawings are for convenience of explanation, and are not limited to this.

[First Embodiment]
FIG. 1 is a schematic perspective view showing an example in which the carbon dioxide generation system according to the first embodiment is used for mosquito collection, and FIG. 2 is a cross-sectional view taken along the line II-II in FIG. The mosquito collector 100 as a carbon dioxide generating system has a box-shaped configuration with a space formed therein, and a carbon dioxide generating unit 1 is disposed below. And the carbon dioxide residence space 3 is provided in the top part, and the mosquito collection unit 2 is arrange | positioned among these. A tank 4 for storing liquid is provided on the side of the mosquito collecting unit 2. Carbon dioxide generated in the carbon dioxide generating unit 1 is sent into the carbon dioxide retention space 3 through the carbon dioxide transfer pipe 5. Note that the mosquito collector may have a configuration other than the box shape (for example, a cylinder).

  A carrier 11 having a photocatalyst fixed on a glass substrate 16 is disposed at the bottom of the carbon dioxide generating unit 1, and a liquid source is supplied above the light source 12 for irradiating the photocatalyst with actinic rays. A liquid supply nozzle 13 is provided for this purpose.

  The support is not particularly limited as long as the support can fix and support the photocatalyst. There are a mode in which a photocatalyst layer is coated on the carrier 11, a mode in which photocatalyst particles are adhered and fixed to the surface of the carrier, and a mode in which the photocatalyst particles are kneaded inside the carrier. Specific examples of the carrier include non-woven fabric, cloth, metal, glass, fiber, alloy, ceramic, resin, metal oxide, metal carbide, metal boride, metal nitride, graphite, and mixtures thereof. The support is preferably a porous body having a large surface area from the viewpoint of efficiently supporting the photocatalyst, and an inorganic binder is preferably used from the viewpoint of durability. Preferable examples of the porous body include porous silica, mesoporous silica, carbon nanotube, and zeolite. Although the contribution of carbon dioxide generation is much less than that of organic molecules contained in the liquid, cloths made of organic materials can also be decomposed by photocatalysis to generate carbon dioxide. However, the cloth or the like mainly serves as a carrier, and although the amount of carbon dioxide generated can be reinforced, the amount of carbon dioxide generated is usually not sufficient.

  When a porous body is used as the support, it is preferable to support the photocatalyst also in the porous portion inside the support. The shape of the carrier is not particularly limited and can be appropriately designed according to the use, but a porous thin film is preferable from the viewpoint of efficiently activating the photocatalyst. Although the film thickness of a porous thin film is not specifically limited, For example, it can be set as about 50 nm-50 micrometers. From the viewpoint of ensuring the catalytic activity and mechanical strength of the porous thin film, the thickness is preferably 50 nm or more, more preferably 2 μm or more, and even more preferably 10 μm. Moreover, from the economical viewpoint for reducing the amount of catalyst, it is preferably 50 μm or less, and more preferably 20 μm or less. The amount of carbon dioxide generated can be adjusted by the type of photocatalyst, the average particle diameter of the photocatalyst, the amount of photocatalyst fixed to the support, the degree of dispersion of the photocatalyst, the active light intensity, the type of support, and the like.

  FIG. 3 shows an example of a schematic diagram of the carrier 11 on which the photocatalyst 10 is carried. A thin film-like carrier 11 is provided on a glass substrate 16, and photocatalyst particles are provided on the surface of the carrier 11 or the surface of the porous portion. By making the carrier 11 a porous thin film, it becomes easy to irradiate the photocatalyst inside the carrier 11 with light. In order to sufficiently irradiate the inside of the support 11 with light, it is preferable that the support has no light absorption or small light absorption in the light irradiated as the active light. Carbon dioxide can be generated with high efficiency by utilizing not only the surface of the support but also the inside for photocatalysis.

  The light source 12 plays a role of irradiating the photocatalyst 10 with an actinic ray. Further, the heat generated by the use of the light source 12 also plays a role as a heat source that attracts mosquitoes. The liquid supply nozzle 13 plays a role of supplying the liquid 40 accommodated in the tank 4 to the carrier 11. It may be supplied by droplets or sprayed. For example, as shown in FIG. 4, the carrier 11 supplied with the liquid 40 is impregnated with the liquid on the surface of the carrier and the inside of the carrier, and the organic molecules 41 adhere to the surface of the carrier or float in the vicinity.

The photocatalyst 10 excited by actinic rays decomposes the organic molecules 41 in the liquid 40 to generate carbon dioxide. The kind of photocatalyst 10 should just satisfy the said conditions, and is not specifically limited. Suitable examples include metal oxide semiconductors composed of titanium dioxide (TiO ₂ ), zinc dioxide (ZnO), strontium titanate (SrTiO ₃ ), tin dioxide (SnO ₂ ), tungsten oxide (WO ₃ ), and the like. A semiconductor obtained by doping may be used. In order to further increase the photocatalytic activity of these semiconductors, platinum (Pt), palladium (Pd), silver (Ag), gold (Au), rhodium (Ru), nickel (Ni), iron (Fe) ), A material supporting a promoter such as a copper compound can also be used. In particular, titanium oxide, zinc oxide, tungsten oxide, and strontium titanate supporting Cu (II) and Fe (III) cluster-like particles are known to exhibit photocatalytic activity under visible light. Can also be used suitably. Titanium dioxide is preferable from the viewpoint of being inexpensive and biosafety is established, and an iron-based or copper-based compound titanium oxide material is preferable from the viewpoint of low cost and visible light responsiveness. A photocatalyst is used alone or in combination of two or more.

  The shape and particle size of the photocatalyst 10 are not particularly limited, but are preferably in the form of particles, for example, those having a size of about 5 to 5000 nm can be used. The shape of the particles can take various forms such as a spherical shape, a flake shape, and a needle shape. From the viewpoint of increasing the production rate of carbon dioxide, the average particle diameter is preferably 10 nm or more and 1000 nm or less. In general, visible light and / or ultraviolet light is preferably used for the active light band of the photocatalyst 10.

  The liquid 40 stored in the tank 4 is supplied to the carrier 11 by the liquid supply means 6. In the first embodiment, the liquid supply means 6 includes a liquid transfer pipe 61, a liquid supply amount adjustment unit 62, a liquid supply nozzle 13, and the like. The amount of liquid supplied by the liquid supply amount adjusting unit 62 is controlled. The liquid supply nozzle 13 may drop droplets or spray it. Further, the liquid supply nozzle 13 may be configured to be freely movable in the XY plane so as to supply the liquid to the surface of the carrier. In the carrier 11 supplied with the liquid, the organic molecules contained in the liquid 40 are oxidized by irradiating with actinic rays, and oxygen in the air is reduced to generate carbon dioxide. From the viewpoint of efficiently performing the oxidation-reduction reaction, it is preferable to supply the liquid so that the portion where the photocatalyst is in contact with the air and the portion where the photocatalyst is in contact with the liquid are present in a balanced manner. The liquid 40 can be replenished to the tank 4 from the liquid inlet 44. In place of the replenishment mode, a liquid cartridge type in which the tank 4 can be freely attached and detached may be mounted.

  The type of organic molecules contained in the liquid is not particularly limited as long as it can generate carbon dioxide. Preferred structures are saturated hydrocarbon resin or / and hydroxyl group, amino group, carboxyl group, epoxy group, isocyanate group, ether bond, glycoside bond, ester bond, amide bond, urea bond, urethane bond, guanidino group, imidazolyl group, indolyl. A group mainly composed of a molecule containing at least one of a group, a mercapto group, a carbonate bond, an acetal bond and an imide bond is preferred. Unless the photocatalytic action of actinic rays is hindered, unsaturated hydrocarbons and the like are also preferably used. Further, from the viewpoint of not generating nitrogen oxides, sulfur oxides, halogen oxides, etc., the organic molecules are preferably composed only of C atoms, O atoms, and H atoms. Further, from the viewpoint of easy decomposition, an organic molecule having a simple molecular structure and easily releasing a carbon bond chain by oxidative decomposition is preferable. Examples of such organic molecules include glycerin and polyvinyl alcohol. Among these, glycerin is particularly preferable because it has a simple molecular structure, and the carbon-bonded chain is easily released by oxidative decomposition and does not require toxicity. An organic molecule can be used individually or in mixture of 2 or more types. In addition, it is preferable to select a solvent so that organic molecules such as glycerin are uniformly dissolved in the solvent to facilitate contact with the photocatalyst, and water does not continuously inhibit the photocatalytic reaction by covering the surface of the photocatalyst. . For example, it is desirable to mix a lower alcohol such as ethyl alcohol which is easily vaporized with water.

  The mosquito collecting unit 2 is configured to be detachable from the carbon dioxide generating unit 1 and the carbon dioxide retention space. A mosquito intrusion opening 20 that is an opening for attracting mosquitoes is provided at the upper side portion of the mosquito collecting unit 2. Further, an air circulation fan 21 is provided inside the mosquito collecting unit 2 in order to circulate the air. The air circulation fan 21 creates an air flow from the mosquito entrance 20 toward the inside of the apparatus, and the mosquito 9 is sucked into the mosquito collecting unit 2 from the mosquito entrance 20. The air circulation fan 21 may be automatically operated in accordance with the operation of the mosquito collector 100, or may be arbitrarily turned on / off. A tapered portion 23 having a smaller area in plan view is provided below the mosquito collecting unit 2 and is configured to become smaller as the area goes downward. The entrance portion 26 on the lower surface of the tapered portion 23 communicates with the mosquito collecting portion 24. The mosquito collecting part 24 is an area where the mosquito 9 is finally captured. A plurality of exhaust ports 25 for releasing the internal air to the outside are provided on the side surface of the mosquito collecting unit 24. The entrance 26 on the upper surface of the mosquito collecting part 24 is provided with an open / close mechanism (not shown) that is isolated from the upper part. When removing the collected mosquitoes, the mosquito collecting part 24 is closed and removed. It can be done.

  The mosquito collecting unit 24 and the carbon dioxide generating unit 1 are configured such that air can move through the air inlet 14. The air from the mosquito collecting unit 24 flows into the carbon dioxide generating unit 1 through the air inlet 14. Then, carbon dioxide generated by the photocatalytic action flows to the carbon dioxide transfer pipe 5 through the exhaust port 15. Carbon dioxide flows into the carbon dioxide retention space 3 through an exhaust port 31 provided at the other end of the carbon dioxide transfer pipe 5.

  One or more discharge ports 30 for discharging carbon dioxide at a high concentration are provided on the side surface of the carbon dioxide retention space 3. The discharge port 30 can be configured to be openable and closable, and the discharge amount and discharge timing can be adjusted according to the mesh size, diameter, thickness, material, and the like. Further, in the carbon dioxide retention space 3, a substance containing a mosquito-like scent (lactic acid or the like) is installed, or a heater for adjusting the temperature of the air containing carbon dioxide released from the discharge port 30 is installed. Thus, mosquitoes can be collected more efficiently near the mosquito collector 100.

  By designing the carbon dioxide generating capacity of the carbon dioxide generating unit 1, the resistance of the intake port 14, the discharge amount of the discharge port 30, the size of the carbon dioxide retention space 3, etc., the concentration of carbon dioxide released from the discharge port 30 to the outside Can be adjusted to a desired concentration. Although the carbon dioxide emission concentration discharged from the discharge port 30 may vary depending on the application, it is preferably 600 ppm or more and preferably 700 ppm or more from the viewpoint of making the concentration sufficiently higher than the carbon dioxide concentration in the atmosphere. More preferably, it is more preferably 800 ppm or more, and particularly preferably 1000 ppm or more. By setting it to 600 ppm or more, mosquitoes can be attracted with high efficiency. Note that the carbon dioxide concentration in the carbon dioxide retention space 3 may be switched as a design that can change the resistance of the intake port 14 and the opening size of the discharge port 30 so that a desired carbon dioxide generation amount can be maintained. Further, the carbon dioxide emission concentration may be adjusted to a desired value by adjusting the ventilation frequency of the carbon dioxide generating unit. By doing in this way, the quantity of the carbon dioxide generated from a carbon dioxide generator can be changed according to a use, and desired carbon dioxide generation amount and concentration can be obtained.

The optimum value of the amount of generated carbon dioxide of the carbon dioxide generating system of the present invention can be varied depending on the application to be used and can be designed as appropriate. However, carbon dioxide is generated with high efficiency by a simple system. From the viewpoint, in the first embodiment, when actinic light with respect to the photocatalyst is irradiated at an intensity of 0.8 mJ / cm ² · sec, carbon dioxide is emitted at normal temperature and normal pressure to 0 per unit area irradiated with actinic light. It is preferable to set so as to satisfy the condition of generating 1 nL / cm ² · sec or more. From the viewpoint of performing carbon dioxide generation with higher efficiency, it is more preferable that, under the above conditions, carbon dioxide is generated at a rate of 0.4 nL / cm ² · sec or more per unit area irradiated with actinic rays, and 0.7 nL / More preferably, it occurs at least cm ² · sec. Furthermore, to promote the photosynthesis of attraction or plants or microorganisms mosquitoes, more preferably at least 1nL ^/ cm 2 · sec, still more preferably at least 2nL ^/ cm 2 · sec, is possible to generate 3nL ^/ cm 2 · sec or more Particularly preferred. From the viewpoint of efficiently generating carbon dioxide, it is preferable that the carrier exhibits a high transmittance with respect to the active light band of the photocatalyst. In addition, the above-mentioned carbon dioxide generation amount should just be implement | achieved by the wavelength which shows the maximum catalyst efficiency.

  In the culture apparatus according to Patent Document 3, by adsorbing bacteria and dust floating around the photocatalyst reaction of titanium dioxide coated on the cloth, it decomposes and generates carbon dioxide. Since carbon dioxide was generated by decomposing organic matter, the concentration of carbon dioxide was too low, far from the amount of carbon dioxide (about 600 ppm) sufficient to attract mosquitoes. On the other hand, according to the carbon dioxide generating system according to the first embodiment, the liquid containing two or more parts of organic molecules that generate carbon dioxide by photocatalytic action is supplied to the photocatalyst. Can be performed efficiently and continuously. From the viewpoint of generating carbon dioxide with high efficiency, it is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and still more preferably 13 parts by mass or more.

  According to the carbon dioxide generation system according to the first embodiment, the organic molecule that generates carbon dioxide by photocatalysis is contained in a liquid in an amount of 2 parts by mass or more, so that a large amount of carbon dioxide is generated around the photocatalyst. Exists. For this reason, compared with the said patent document 3, the carbon dioxide generation amount can be increased significantly. Moreover, the mosquito attracting effect can be enhanced by the heat generation effect of the light source 12. In addition, mosquitoes can be collected without using insecticides or electric shock methods, and by using a safe component as a liquid component, the human body is not harmed and is safe.

[Second Embodiment]
The mosquito trap according to the second embodiment includes a self-destructive component that is decomposed by a photocatalyst and generates carbon dioxide in at least a part of the carrier. In the following drawings, the same element members are denoted by the same reference numerals as those in the first embodiment, and the description thereof is omitted as appropriate.

  FIG. 5 is a schematic diagram for explaining the photocatalyst carried on the carrier and the supplied organic molecule according to the second embodiment. The carrier 11e has an organic binder as a main component, and the carrier itself kneaded with the photocatalyst 10 self-destructs to generate carbon dioxide.

Although it will not specifically limit if it self-destructs by the photocatalytic action (oxidation action) of a photocatalyst and generate | occur | produces a carbon dioxide, The active ray with respect to the photocatalyst 10 was irradiated to the support body 11e with the intensity | strength of 0.8 mJ / cm < ² > / sec. In this case, carbon dioxide is preferably generated at 0.05 nL / cm ² · sec or more per unit area irradiated with actinic rays at normal temperature and normal pressure, more preferably at least 0.1 nL / cm ² · sec. preferable.

  The carrier 11e is not particularly limited as long as it is solid, but preferred examples include beads, films, sheets, gels, non-woven fabrics, cloths, and molded articles having a desired shape. These may be formed alone or on a support such as a substrate. The nonwoven fabric can be formed of, for example, cellulose fiber, nylon fiber, vinylon fiber, polyester fiber, polyolefin fiber, rayon fiber, or the like. It is possible to use a non-woven fabric that is a carrier, in which photocatalyst particles such as titanium oxide are entangled and fixed. Further, a nonwoven fabric made of carbon fiber impregnated with an organic binder may be used as the carrier.

  By using the carrier (organic binder) 11e according to the second embodiment, in addition to a mechanism for decomposing the organic molecules 41 in the liquid 40 by the photocatalyst to generate carbon dioxide, at least a part of the carrier is self-destructed. Carbon dioxide can be generated. For this reason, carbon dioxide can be generated more efficiently.

  The type of the organic binder is not particularly limited, but from the viewpoint of generating carbon dioxide by promoting self-destruction by a photocatalyst, saturated hydrocarbon resin or / and hydroxyl group, amino group, carboxyl group, epoxy group, isocyanate group, ether bond, glycoside The main component is preferably a resin containing at least one of a bond, ester bond, amide bond, urea bond, urethane bond, guanidino group, imidazolyl group, indolyl group, mercapto group, carbonate bond, acetal bond and imide bond. Unless the photocatalytic action of actinic rays is hindered, unsaturated hydrocarbons and the like are also preferably used. Further, from the viewpoint of not generating nitrogen oxides, sulfur oxides, halogen oxides, etc., the resin is preferably composed only of C atoms, O atoms, and H atoms. From the viewpoint of ease of decomposition, a resin having a simple molecular structure and easily detaching a carbon bond chain by oxidative decomposition is preferable. An example of such a resin is a resin having a long-chain hydrocarbon structure. Specific examples include polysaccharides such as cellulose, hydrocarbon compounds such as liquid paraffin, carboxyl group-containing resins such as vinyl acetate, and hydroxyl group-containing resins such as polyvinyl alcohol. Among these, cellulose is particularly preferable because it contains a large number of carbon atoms, has a simple molecular structure, and easily detaches a carbon bond chain by oxidative decomposition. The organic binder can be used alone or in combination of two or more.

  Examples of the method for forming the film include a method in which a photocatalyst and an organic binder dispersed or dissolved in a solvent are coated on a support and dried, a method of bonding via an adhesive layer, and a method of lamination. As a method for forming the kneaded product, a known method such as a method of dispersing an organic binder and a photocatalyst in a solvent can be used without limitation. Although it does not specifically limit as a support body, Plastics and glass, such as a polyethylene terephthalate, can be utilized suitably.

  In the second embodiment, since the carrier having self-destructive property is used at least in part, the carbon dioxide generation efficiency can be increased. Moreover, since the liquid is supplied, the degree of self-destruction of the carrier itself can be suppressed. For this reason, the stable carbon dioxide supply is realizable.

(Modification)
Hereinafter, although the modification of the said embodiment is demonstrated, this invention is not limited to the following description, A various deformation | transformation is possible.

  In the above-described embodiment, the example in which the light source 12 is used for the carbon dioxide generation unit 1 has been described. However, the photocatalyst may be activated by taking in external light (sunlight or room light) without using the light source. Moreover, you may use a light source and external light together. For example, the light source 12 may be turned off when the photocatalyst can be sufficiently excited by sunlight or room light, and the light source may be turned on when sunlight or room light is weak or unavailable. Whether the light source is on or off may be determined by, for example, sunlight / indoor light intensity measurement unit (not shown). Even when the amount of light is sufficient due to sunlight or the like, the light source may be used for attracting mosquitoes by a heat source or ultraviolet light. In the case of taking in light from the outside, a material that can transmit the active light of the photocatalyst is used. That is, a visible light transmissive material is used for a visible light responsive photocatalyst, and an ultraviolet light transmissive material (for example, a plastic material or glass) is used when an ultraviolet light responsive photocatalyst is used. . Since mosquitoes have an infrared sensing function and characteristics attracted by ultraviolet light, a heat source may be provided in the vicinity of the mosquito entrance.

  Moreover, arrangement | positioning of the carbon dioxide generation unit 1, the mosquito collection unit 2, and the carbon dioxide retention space 3 is not limited to the said embodiment. For example, the carbon dioxide generating unit 1 may be provided in the upper part and the mosquito collecting unit 2 may be provided in the lower part, and the carbon dioxide retention space 3 may be provided between them.

  Although the aspect of spraying or dropping droplets from above the carrier using the liquid supply nozzle as the liquid supply means has been described, various modifications are possible. For example, as shown in the mosquito trap 101 of FIG. 6, the liquid 40 may be supplied to the carrier 11 by storing the liquid at the bottom of the carbon dioxide generation unit 1 a and immersing the carrier 11 in the liquid 40. . The liquid supply means 6a according to the modification includes a support body 64 that supports the carrier, and a height adjusting means 63 that freely adjusts the height of the support body 64 in the y-axis direction in the drawing. One end of the support 64 is fixed to the glass substrate 16, and the other end is held by the height adjusting means 63 so that the height can be adjusted. At a desired timing, the support 64 extends downward in the Y-axis direction in the drawing, and the carrier 11 is immersed in the liquid 40. Then, the carrier 11 is pulled up again and placed at a predetermined position. Thereby, the liquid can be supplied to the carrier 11. Moreover, it is good also as a mechanism which makes a liquid flow on the support body surface using a pump, and collect | recovers again. Alternatively, the carrier may be half immersed in the liquid by buoyancy, and the liquid may be supplied to a portion where the liquid is not immersed on the surface of the carrier by surface tension.

  FIG. 7 is a schematic diagram of a mosquito trap 102 according to a second modification. As shown in the figure, a configuration may be adopted in which the carbon dioxide generation unit 1b is directly provided with the discharge port 30b and the carbon dioxide is released therefrom without providing the carbon dioxide retention space 3. According to this configuration, the apparatus can be simplified.

  FIG. 8 is a schematic diagram of a mosquito trap 103 according to a third modification. As shown in the figure, the mosquito trap 103 is provided with a box-type carbon dioxide generating unit 1c, and an adhesive sheet 80 is provided on the outer top surface 19 thereof. Further, an air inlet 18 is provided on the side of the carbon dioxide generating unit 1c, and an air circulation fan (not shown) is provided in the vicinity of the air inlet 18. By this air circulation fan, air is sucked into the carbon dioxide generating unit 1c. And the carbon dioxide which generate | occur | produced in the carbon dioxide generation unit 1c is discharged | emitted from the discharge port 30c. One or more discharge ports 30c may be provided. The vicinity of the discharge port 30c is an environment in which the concentration of carbon dioxide is high and the temperature from the light source 12 is higher than that of the surroundings due to heat from the light source 12, and the mosquito 9 is easily attracted. The top of the carbon dioxide generating unit 1c is provided with a U-shaped cover 81 having openings on both the front and rear sides in the figure. The cover 81 has an effect of suppressing the diffusion of carbon dioxide discharged from the discharge port 30c. In the example of FIG. 8, the tank 4 is a detachable cartridge type, and can be easily replaced with a new one when the liquid 40 runs out. The pressure-sensitive adhesive sheet 80 can employ a method of drawing out a roll-shaped pressure-sensitive adhesive sheet and winding it after use. The configuration of FIG. 8 has an advantage that the apparatus can be simplified.

  A heater and / or an odor generating substance may be provided in the vicinity of the discharge port. In addition to attracting mosquitoes by carbon dioxide, mosquitoes can be attracted more effectively by temperature and odor generating substances. The odor generating substance may be included in the liquid 40. In this case, there is an advantage that the device configuration is easy. It should be noted that odor generating substances, such as aromatic compounds, have the property of being decomposed by a photocatalyst, but select a substance that is more dominant in volatilization than the decomposition by a photocatalyst when liquid is supplied to the carrier. Is preferred.

[Third Embodiment]
Next, an example in which the carbon dioxide generating system is used for plant growth promotion will be described. FIG. 9 shows a schematic explanatory diagram of an example of a carbon dioxide generation system according to the third embodiment. In the carbon dioxide generation system 200, carbon dioxide having a desired concentration is supplied from a box-shaped housing 70 to a plant cultivation container 73 via a pipe 71. A concentration sensor 74 for measuring the concentration of carbon dioxide is provided in the plant cultivation container 73, a control valve 72 is provided in the pipe 71, and the carbon dioxide in the plant cultivation container 73 is based on the measurement result of the concentration sensor 74. The concentration is kept constant. A plurality of air inlets 76 are provided at the top of the side surface of the housing 70 so that air containing high-concentration carbon dioxide generated in the housing 70 can be smoothly sent to the plant cultivation container 73.

  A cylindrical light source 12p is provided in the center of the housing 70, and an air circulation fan (not shown) for sending carbon dioxide to the plant cultivation container 73 is provided in the vicinity of the bottom. A carrier 11e carrying a photocatalyst is disposed at the bottom of the housing 70, and a liquid supply nozzle 13p for supplying liquid to the carrier and a light source 12p are disposed above the carrier 11e. The internal space of the housing 70 is a staying space 77 that stores high-concentration carbon dioxide generated from the photocatalyst. The carbon dioxide filled in the staying space 77 is supplied into the box-shaped plant cultivation container 73 through the pipe 71 by the flow by the air circulation fan and the control valve 72. A plurality of pipes 71, control valves 72, and the like can be provided in the Y-axis direction in the drawing according to the scale.

  According to the carbon dioxide generation system 200, carbon dioxide can be easily supplied to the plant cultivation container 73 by an external device. Further, since the liquid 40 is configured to be replenishable, it can be easily replenished when the liquid runs out.

(Modification)
In the third embodiment, an LED sheet may be used instead of the light source 12p. In addition to the mode in which the support 11 is arranged at the bottom, a support having a wound structure is incorporated, and a liquid containing organic molecules is immersed in the lower part of the support using a support having a water absorption property. May be installed directly on the wall surface of a box-type plant factory. Moreover, it is not limited to a plant factory use, You may install this system in plant cultivation kits, such as a vegetable and a flower.

  The present invention is not limited to the above-described embodiments and modifications, and it goes without saying that other embodiments may belong to the category of the present invention as long as they match the gist of the present invention. Moreover, the said embodiment and modification are mutually combined suitably.

<Example>
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
A photocatalyst was added to ethyl cellulose, and a paste was formed using α-terpineol as a solvent. This was coated on a glass substrate by screen printing a desired number of times. Subsequently, the porous thin film containing a photocatalyst was produced by baking at 500 degreeC for 1 hour. Titanium dioxide (P-25, manufactured by Degussa) was used as the photocatalyst particles. A porous thin film having a thickness of about 20 μm was obtained by firing.

As a liquid, 53 parts by mass of water, 34 parts by mass of ethyl alcohol, and 13 parts by mass of glycerin were sprayed with 0.4 CC per 100 cm ² of the support surface area of the porous thin film, and ultraviolet light (black light) in a band of 300 to 400 nm. ) Was examined at an intensity of 0.8 mJ / cm ² · sec.

  FIG. 11 shows the result of plotting the number of screen printings, that is, the production rate of carbon dioxide against the thickness of the carrier. The thickness when screen printing was performed once was about 5 μm, and the carbon dioxide production rate when the thickness was 5 μm was evaluated as 1.

  FIG. 11 shows that the carbon dioxide generation rate increases as the number of screen printings increases. In order to obtain a desired carbon dioxide production rate, the number of layers, the thickness, and the like may be appropriately designed according to the type and amount of photocatalyst in consideration of the light reachable range.

From FIG. 12, carbon dioxide of 4 to 5 nL / cm ² sec was generated over 1250 minutes (about 21 hours) simply by spraying 0.4 CC per 100 cm ² of the surface area of the support. That is, it can be seen that by supplying the liquid every 21 hours, air containing a certain amount of carbon dioxide can be released from the mosquito trap for a long time.

Using this titanium dioxide (P-25, manufactured by Degussa), a thin film was formed by performing screen printing three times on a substrate made of glass having a size of 12 cm × 10 cm. Then, in the mosquito trap shown in FIG. 7, a substrate with a carrier is installed at the bottom of the carbon dioxide generating unit, and after spraying 0.4 CC of liquid per 100 cm ² of the surface area of the carrier, 0.8 mJ / cm ² · sec The amount of carbon dioxide generated when irradiated with ultraviolet light was calculated. The internal size of the mosquito collecting unit is 100 (width) x 120 (length) x 110 (height) mm, and the carbon dioxide generation unit is 100 (width) x 120 (length) x 40 (height) mm. It was. Further, the flow rate of the air circulation fan was set to 640 cc / min, and the size of the discharge port 30b was set to 10 mm × 10 mm. And the flow velocity of this discharge port 30b was adjusted to be 0.35 cm / sec. Further, the suction size of the mosquito entrance 20 was 8 mmφ × 3 sets, the flow rate was 6.9 cm / sec, and the size of the tank 4 was 20 × 120 × 85 mm (204 cm ³ ). Then, 0.48 cc was supplied once every 21 hours as a liquid supply amount to the carrier. As described above, the composition ratio of the organic liquid was water: ethyl alcohol: glycerin = 53: 34: 13 by mass ratio. The carrier size was 100 × 120 mm. The concentration of carbon dioxide released from the outlet 30b was 920 ppm, and the amount of carbon dioxide-containing air released was set to 64 cc / min.

Under the above conditions, the following results were obtained.
(1) The carbon dioxide gas concentration of the carbon dioxide generating unit exceeds 900 ppm in 8 minutes after irradiation with ultraviolet light (the environmental concentration is 400 ppm, that is, the generated carbon dioxide concentration exceeds 500 ppm). This is a concentration exceeding 600 ppm that can attract mosquitoes.
(2) When the ventilation frequency of the carbon dioxide generating unit is 8 times per hour, the air containing carbon dioxide released from the carbon dioxide generating unit per hour is 3840 cm ³ / h, the concentration is 920 ppm (the environmental concentration is 400 ppm) Therefore, the generated carbon dioxide concentration is 520 ppm), and carbon dioxide having this concentration can be continuously supplied for a long time.
(3) The required volume of the liquid for maintaining the above (1) and (2) is 200 cm ³ per year when 0.48 cc is sprayed once every 21 hours on a 120 cm ² carrier. Therefore, one year of maintenance-free operation can be realized with the size of the tank 4 described above.

Incidentally, CO ₂ is exhaled amount of human occurs during ^{sleep: 0.37m} 3 ^{/h=6.2L/min,CO} ₂ concentration to 4%, CO ₂ emissions: 6.2 × 0.04 = because it is ^{0.248L / min = 248cm 3 / min} = 14480cm 3 / h, the CO ₂ that occurs less than CO ₂ human generated during sleep, there is no risk of harm to humans.

DESCRIPTION OF SYMBOLS 1 Carbon dioxide generation unit 2 Mosquito collection unit 3 Carbon dioxide retention space 4 Tank 5 Carbon dioxide transfer pipe 6 Liquid supply means 9 Mosquito 10 Photocatalyst 11 Carrier 12 Light source 13 Liquid supply nozzles 14 and 18 Intake port 15 Exhaust port 16 Glass substrate 20 Mosquito Intrusion Port 21 Air Circulation Fan 22 Outer Tube 23 Tapered Portion 24 Mosquito Collection Portion 25 Exhaust Port 26 Entrance Port 30 Release Port 31 Exhaust Port 40 Liquid 61 Liquid Transfer Pipe 62 Liquid Supply Amount Adjusting Unit 63 Height Adjusting Means 64 Support Body 70 Housing 71 Piping 72 Control valve 73 Plant cultivation container 74 Concentration sensor 76 Inlet port 77 Retention space 80 Adhesive sheet 81 Cover 100 to 103 Mosquito collector 200 Carbon dioxide generation system

Claims (11)

A photocatalyst,
A carrier for immobilizing the photocatalyst;
Liquid supply means for supplying the photocatalyst with a liquid containing an organic molecule that decomposes by the photocatalytic action of the photocatalyst to generate carbon dioxide,
The liquid includes water and an organic solvent compatible with the water,
Containing 2 parts by mass or more of the organic molecule with respect to 100 parts by mass of the liquid;
A carbon dioxide generating system that continuously generates carbon dioxide by repeatedly supplying the liquid to the carrier and consuming the liquid on the carrier. Furthermore, a carbon dioxide retention space for retaining the carbon dioxide,
The carbon dioxide generating system according to claim 1, further comprising a discharge port that releases the carbon dioxide in the carbon dioxide retention space at a concentration of 600 ppm or more.   The carbon dioxide generating system according to claim 1 or 2, wherein the carrier is made of a porous body, and the photocatalyst is also carried on a porous portion inside the carrier.   The carbon dioxide generating system according to any one of claims 1 to 3, wherein the carrier is a porous thin film. The photocatalyst is a metal oxide semiconductor containing at least one selected from TiO ₂ , ZnO, SrTiO ₃ , SnO ₂ and WO ₃ which may have a promoter.
The carbon dioxide according to any one of claims 1 to 4, wherein the promoter is a substance containing at least one of Pt, Pd, Cu (II), Fe (III), Au, Ag, Ru, and Ni. Generating system. The carbon dioxide generating system according to any one of claims 1 to 5 , which is used for capturing mosquitoes. The carbon dioxide generating system according to any one of claims 1 to 5 , which is used for promoting plant growth. Furthermore, the carbon dioxide generation system of Claim 6 provided with the odorous substance which a mosquito likes. Furthermore, the carbon dioxide generation system of any one of Claims 1-8 provided with the light source which can excite the said photocatalyst. Further, the carbon dioxide generating system according to any one of claims 1 to 9, comprising a heat source. A liquid cartridge mounted on a carbon dioxide generating system according to any one of claims 1 to 1 0,
The carbon dioxide generation system includes:
A photocatalyst, a carrier for immobilizing the photocatalyst, and a liquid supply means for supplying the photocatalyst with a liquid containing organic molecules that are decomposed by the photocatalytic action of the photocatalyst to generate carbon dioxide,
A liquid cartridge configured to store the liquid and to be able to supply the liquid to the carrier via the liquid supply means and to be detachable from the carbon dioxide generation system.

Images