WO2022168519A1

WO2022168519A1 - Photocatalyst composition, method for producing same, and deodorizing agent

Info

Publication number: WO2022168519A1
Application number: PCT/JP2022/000093
Authority: WO
Inventors: 森川クラウジオ健治
Original assignee: 国立研究開発法人農業・食品産業技術総合研究機構
Priority date: 2021-02-04
Filing date: 2022-01-17
Publication date: 2022-08-11
Also published as: JPWO2022168519A1

Abstract

Provided is an inexpensive photocatalyst composition which can be used for the decomposition or sterilization of an organic substance, which is not limited in terms of uses, which allows impacts on the human body and the environment to be suppressed, and which exhibits excellent photocatalytic activity in a wide range of wavelengths including that of visible light.　This photocatalyst composition exhibits catalytic activity with visible light and contains a glass material, an iron-supplying raw material, and a reducing organic substance that has the effect of reducing trivalent iron to bivalent iron. The reducing organic substance contains a polyphenol and/or ascorbic acid, and the iron-supplying raw material contains a bivalent iron compound and/or a trivalent iron compound.

Description

Description Title of invention: Photocatalyst composition, method for producing the same, and deodorant Technical field

[0001] The present disclosure relates to a photocatalyst composition exhibiting photocatalytic activity with respect to visible light, a method for producing the same, and a deodorant. Background technology

[0002] In recent years, contamination caused by harmful microorganisms such as viruses (new coronavirus, avian influenza virus, swine fever virus, etc.) and pathogenic E. coli (0-157, etc.) has become a social problem all over the world. . Photocatalysts are attracting attention as one of the sterilization technologies for such harmful microorganisms. Since photocatalysts can be used to decompose harmful organic substances and sterilize them simply by exposing them to light, social needs are increasing as a simple and highly versatile technology.

[0003] In addition to titanium oxide, tungsten and indium exhibit photocatalytic activity.

, vanadium, silver, molybdenum, zinc, gallium phosphide, gallium, arsenic and other metal compounds are known. However, most of these metal compounds are very expensive and highly toxic, so they have not been put to practical use, and at the present stage, only titanium oxide is put into practical use as a photocatalyst. Furthermore, since these metal compounds are substances that exhibit photocatalytic activity only at ultraviolet wavelengths of 400 nm or less, they can be used for sterilization and decomposition in living spaces where only visible light such as fluorescent lights can be used. are not suitable and have limited use.

[0004] Also, in order to achieve photocatalytic activity with visible light, a technique of mixing impurities (doping) has been attempted. No photocatalytic activity has been obtained and there are no products that have been put to practical use.

[0005] On the other hand, photocatalysts centering on polyphenol iron complexes have also been developed (see, for example, Patent Document 1). Since the photocatalyst described in this patent document 1 absorbs light of a wide range of wavelengths including visible light and shows activity, it is possible to expand the usage scene. Become. In addition, since plant bodies or their processed products are used as raw materials without using rare metals, there is little impact on the human body and the environment, and photocatalysts can be provided at low cost. In addition, an invention of a photocatalytic glass containing an iron component has been disclosed in order to improve the durability of the photocatalyst and enable stable photocatalytic activity (see Patent Documents 2 and 3).

[0006I] From the above situation, it was expected to develop an inexpensive photocatalyst that can suppress the impact on the human body and the environment without being limited to the usage scene, and that exhibits excellent photocatalytic activity in visible light.

〇 Prior art documents Patent documents

[0007] Patent Document 1: Japanese Patent No. 6340657 Patent Document 2: Japanese Unexamined Patent Application Publication No. 2011-241138 Patent Document 3: Japanese Unexamined Patent Application Publication No. 2015-16 7871 Gazette Overview of the invention Problems to be solved by the invention

[0008] The present invention solves the above problems, can be used for organic matter decomposition or sterilization, is not limited to usage scenes, can suppress the effects on the human body and the environment, and has a wide range of wavelengths including visible light. An object of the present invention is to inexpensively provide a photocatalyst composition exhibiting excellent photocatalytic activity to light. Means to solve problems

[0009] As a result of extensive research, the present inventors discovered that polyphenols and an iron source

, found that the polyphenol-iron complex obtained by mixing in the presence of water exhibits photocatalytic activity against not only ultraviolet light but also visible light and infrared light. In addition, the inventors thought that by bonding carbon and divalent iron in the polyphenol-iron complex, the stability of the polyphenol-iron complex could be enhanced and a stable photocatalyst could be obtained. When a glass was produced using polyphenols and an iron supply source, it was found that excellent photocatalytic activity could be maintained and stability as a photocatalyst could be enhanced. [0010I The present disclosure has been made based on these findings. That is, the photocatalyst composition according to the present disclosure is a photocatalyst composition that exhibits catalytic activity with visible light, and includes a reducing organic substance that has the action of reducing trivalent iron to divalent iron, an iron supply raw material, and a glass material. wherein the reducing organic matter contains at least one of polyphenols and ascorbic acid; and the iron feedstock contains at least one of divalent iron compound and trivalent iron compound. Moreover, the deodorant according to the present disclosure contains the photocatalyst composition that exhibits catalytic activity with visible light as described above. Further, a method for producing a photocatalyst composition according to the present disclosure is a method for producing a photocatalyst composition that exhibits catalytic activity with visible light as described above, and has an action of reducing trivalent iron to divalent iron. A step of heat-treating the reducing organic substance, the iron feedstock, and the glass material in a reducing atmosphere at a heating temperature of ⁹⁰⁰⁰ C or higher for a heating time of 12 minutes or longer. Effect of the invention

[001 1] The photocatalyst composition of the present disclosure has the property of exhibiting activity when irradiated with not only ultraviolet light but also visible light and infrared light, so it can be used in ordinary indoor spaces. In addition, since polyphenols and ascorbic acid are used as iron-reducing organic substances as raw materials, the photocatalyst of the present disclosure can suppress the effects on the human body and the environment. As a result, the photocatalyst composition of the present disclosure can be used in various applications in which conventional titanium oxide was difficult to use.

[0012] Therefore, a photocatalyst composition that can be used for decomposition or sterilization of organic matter, is not limited to usage situations, can suppress the effects on the human body and the environment, and exhibits excellent photocatalytic activity with respect to a wide range of wavelengths including visible light. can be provided at low cost. A brief description of the drawing

[0013] [Fig. 1] A flow chart showing an example of a process for producing a photocatalyst composition according to the present embodiment.

[Fig. 2] A photographic image diagram for explaining the photocatalyst composition of Example 1, (a) showing a photographic image diagram of the photocatalyst composition (plate glass) of Example 1 before pulverization, (b) powder 1 shows a photographic image of the photocatalyst composition (powder glass) of Example 1 after pulverization, and (C) is a photographic image of the photocatalyst composition of Example 1 after pulverization of (b) dyed with dipyridyl. indicates

[Fig. 3] Spectrum distribution of white LED light used in the experimental example.

[Fig. 4] Fig. 4 is a diagram for explaining the effect of decomposing harmful substances by a photocatalyst composition when irradiated with white LED light, (a) showing a graph showing the results of a verification experiment of the decomposition effect, (b) (c) shows a photographic image of the solution of the control group using titanium oxide, and (c) shows a photographic image of the solution of the photocatalyst composition of Example 1 irradiated with white LED light.

[Fig. 5] A photographic image for explaining the effect of decomposing harmful substances by a photocatalyst composition when irradiated with ultraviolet rays. 1 shows a photographic image of the solution in the ultraviolet irradiation section using the photocatalyst composition of Example 1, and (c) shows a photographic image of the solution in the titanium oxide section using titanium oxide.

[Fig. 6] A photographic image for explaining the effect of decomposing harmful substances by a photocatalyst composition when irradiated with ultraviolet rays. b) shows a photographic image of the solution in the titanium oxide section using titanium oxide, and (○) shows a photographic image of the solution in the near-infrared irradiation section using the photocatalyst composition of Example 1.

[Fig. 7] Fig. 7 is a photographic image for explaining the effect of sterilizing E. coli by the photocatalyst composition of Example 1, (a) showing a photographic image of the control group "light irradiation only treatment group", ( b) shows a photographic image of the “dark condition section” using the photocatalyst composition, which is the control section, and (○) shows a photographic image of the “white LED light irradiation section” using the photocatalyst composition.

[Fig. 8] A diagram for explaining the bactericidal effect of E. coli by the photocatalyst composition of Example 1. (a) shows the survival of E. coli in the "dark condition section" using the photocatalyst composition, which is a control group. The determination results are shown, and (b) shows the determination results of life and death of E. coli in the "white LED light irradiation area" using the photocatalyst composition.

[Fig. 9] A diagram for explaining the bactericidal effect of the photocatalyst composition of Example 1 against bacterial wilt disease. (b) shows the results of determining whether bacteria are alive or dead, and (b) shows a “white LED light irradiation using a photocatalyst composition. The results of life-and-death determination of bacterial wilt fungus in the ward are shown.

[Fig. 10] Fig. 10 is a diagram showing the results of a radical species identification experiment by luminol reaction of the photocatalyst composition of Example 1. [Fig.

[Fig. 11] Fig. 11 is a diagram showing the results of a superoxide radical identification experiment using the MPEC reagent of the photocatalyst composition of Example 1. [Fig.

[Fig. 12] Fig. 12 is a diagram showing the measurement results of the ESR spectrum obtained by irradiating the photocatalyst composition of Example 1 with ultraviolet LED light.

[Fig. 13] Fig. 13 is a diagram showing the results of ESR analysis by irradiating the photocatalyst composition of Example 1 with white LED light (visible light irradiation).

[Fig. 14] Fig. 14 is a photographic image for explaining the effect of preserving the freshness of cut flowers (camellia) by the photocatalyst composition of Example 2, where (a) is a photographic image showing the state of irradiation with white LED light. , and (b) shows a photographic image of the light irradiation section 10 days after the start of the experiment,

(O) shows a photographic image of the control group 10 days after the start of the experiment.

[Fig. 15] Fig. 15 is a photographic image for explaining the effect of preserving the freshness of other different cut flowers (Saponaria baccaria) by the photocatalyst composition of Example 2. (a) is the area irradiated with white LED light at the start of the experiment. and (b) are photographic images of the control plot, and (b) is a photographic image of the white LED light irradiation plot and the control plot three days after the start of the experiment.

[Fig. 16] Fig. 16 is a photographic image diagram for explaining the seed sterilization effect of the photocatalyst composition of Example 2, (a) showing a photographic image diagram of the control group 7 days after the start of the experiment, and (b) showing a photographic image diagram. A photographic image of the light-irradiated section 7 days after the start of the experiment is shown.

[Fig. 17] Fig. 17 is a photographic image for explaining the seed sterilization effect (bacteria sterilization effect) of the photocatalyst composition of Example 2, where (a) is a photograph of the growth state of chickpeas in the control plot. (b) shows a photographic image of the breeding state of various bacteria in chickpeas irradiated with ultraviolet LED light.

[Fig. 18] A diagram showing the extraction process of silica from diatoms in Examples 5 and 6.

[Fig. 19] Fig. 19 is a diagram for explaining the effect of decomposing harmful substances by the photocatalyst composition of Example 5, (a) showing a graph showing the results of a verification experiment of the decomposition effect, (b) shows photographic images of the solutions in the LED light irradiation area and the control area 4 hours after the start of the experiment. 20 is a diagram for explaining the effect of decomposing harmful substances by the photocatalyst composition of Example 6, (a) showing a graph showing the results of an experiment to prove the decomposition effect, and (b) from the start of the experiment. Shown are photographic images of the solutions in the LED light irradiation area and the control area after 4 hours. MODE FOR CARRYING OUT THE INVENTION

[0014] Hereinafter, embodiments of the present disclosure will be described in detail.

(Photocatalyst Composition) The photocatalyst composition according to the present embodiment is a photocatalyst composition that exhibits catalytic activity under visible light, and comprises a reducing organic substance that has the action of reducing trivalent iron to divalent iron, and an iron supply raw material. and containing a glass material. The photocatalytic composition of the present embodiment is preferably photocatalytic glass or photocatalytic glass-ceramics. In addition, the iron feedstock contains at least one of a divalent iron compound and a trivalent iron compound, and the reducing organic substance is at least one of polyphenols and ascorbic acid.

[Reducing organic substance] [0015] The photocatalyst composition of the present embodiment uses "a reducing organic substance having an action of reducing trivalent iron to divalent iron" as a raw material for supplying carbon. Hereinafter, this "reducing organic substance having the action of reducing trivalent iron to divalent iron" may be referred to as "reducing organic substance having iron-reducing ability" or simply "reducing organic substance".

[0016] Specific examples of the reducing organic substance include ascorbic acid and polyphenols. In addition to these compounds, the plant body or its processed product may contain a large amount of reducing organic matter having iron-reducing ability, and can be suitably used as the reducing organic matter.

[0017] Here, as "ascorbic acid", not only free acid of ascorbic acid but also ascorbic acid compounds (potassium ascorbate, sodium ascorbate, etc.) can be used.

[0018] "Polyphenols" is a general term for phenolic molecules having multiple hydroxy groups. “Polyphenols” are compounds contained in most plants. It is a substance, and various types such as flavonoids and phenolic acids are known. Specific examples of polyphenol compounds include catechin (epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate, etc.), tannic acid, tannin, chlorogenic acid, caffeic acid, neochlorogenic acid, cyanidin, Proanthocyanidins, thearubigins, rutin, flavonoids (quercitrin, anthocyanins, flavanones, flavanols, flavonols, isoflavones, etc.), flavones, chalcones (naringenin chalcone, etc.), xanthophylls, carnosic acid, eriocitrin, nobiletin, Tangeretin, magnolol, honokiol, ellagic acid, lignans, curcumin, coumarin, catechol, procyanidins, theaflavin, zumaric acid, xanthones, quercetin, resveratrol, gallic acid, phlorotannins, and the like. Also included are compounds having one or more of these compounds in the molecule (for example, complexes in which these compounds are combined and polymerized).

[0019I In addition, a polyphenol composition extracted from a certain fruit is sometimes called a polyphenol with the name of the fruit. For example, polyphenol compositions extracted from grape berries are referred to as grape polyphenols. In addition, in the present embodiment, it is preferable to use a refined product of the compound as described above as a raw material of the reducing organic substance because the activity of the photocatalyst is increased.

• Feedstock of reducing organic matter In the present embodiment, a plant containing at least one of polyphenols and ascorbic acid or a processed product thereof can be used as a feedstock of reducing organic matter. Examples of the plant body include those derived from one or more selected from fruits, seeds, foliage, buds, flowers, roots, and rhizomes.

[0021] Plant materials containing a large amount of ascorbic acid include, for example, tomatoes, green peppers, red peppers, winter melons, bitter melons, zucchini, cucumbers, green peas, pumpkins, eggplants, green peas, broad beans, green soybeans, okra, acerola, and citrus fruits. (lemon, lime, orange, grapefruit, navel, yuzu, kin Kan, Kabosu, Natsumikan, Hassaku, Iyokan, Rye, Satsuma Mandarin, Shikuwasa, Mandolin, etc.), Persimmon, Kiwifruit, Papaya, Blackberry, Blueberry, Cranberry, Raspberry, Bilberry, Huckleberry, Strawberry, Melon, apple, pear, pear, fig, peach, plum, guava, grape, prune, akebi, durian, pineapple, mango, banana, cherry, pomegranate, watermelon, gummy, loquat, cassis, chestnut, lychee, Ginkgo nut, Olive, Avocado, Tea, Lettuce, Cabbage, Kale, Mustard mustard, Mizuna, Komatsuna, Daikon radish, Turnip, Rapeseed, Chinese cabbage, Bok choy, Takana mustard, Nozawana, Moroheiya, Green onion, Garlic, Garlic, Spring onion, Chive, Onion , shallots, shiso, ashitaba, tsurumurasaki, watercress, asparagus, basil, parsley, celery, parsley, spinach, chrysanthemum, bamboo shoots, broccoli, cauliflower, sweet potato, potato, yam, lotus root, turnip, radish, Brussels sprouts, seaweed (seaweed, wakame seaweed, kelp, sea lettuce, etc.)

[0022I] Plant raw materials containing a large amount of polyphenols include, for example, herbs (lavender, mint, coriander, cumin, sage, lemongrass, mugwort, comfrey, perilla, lemon balm, oregano, coconut nip, common thyme , dill, dark opal, basil, hyssop, peppermint, lamb's ear, etc.), houttuynia cordata, marigold, grape, coffee (coffee tree), tea (tea tree), cacao, acacia, cedar, mat, sugarcane, mango, banana, papaya, Avocados, apples, cherries (cherry peaches), guavas, olives, potatoes (sweet potatoes, purple potatoes (sweet potatoes containing a lot of purple pigment), potatoes, yams, taro (taro, shrimp, etc.), konjac potatoes, etc.), persimmons (persimmon), mulberry, blueberry, poplar, ginkgo biloba, chrysanthemum, sunflower, bamboo, citrus fruits (lemon, lime, orange, grapefruit, navel, yuzu, kumquat, kabosu, summer orange, hassaku, iyokan, lime, unshu mandarin) , Shikwasa, Mandarin, etc.) , Strawberry, Blackberry, Cranberry, Raspberry, Bilberry, Huckleberry Plum, Peach, Prunus, Pear, Pear, Loquat, Kiwifruit, Mangosteen, Shishito, Prunes, Melon, Dragonfruit, Wolfberry, Cassis, Cashew, Viburnum, Pomegranate, Acai, Aronia, Eggplant, Tomato, Soybean , black soybeans, adzuki beans, green beans, peanuts, black sesame, buckwheat, tartary buckwheat, sesame seeds, purple cabbage, sumac, nurde, shungiku, broccoli, spinach, komatsuna, mitsuba, okra, stamens, onions, molokhiya, chrysanthemum, garlic, purple Onions, asparagus, parsley, eucalyptus, udo, Gymnema sylvestre, senna, dandelion, horsetail, fern (bracken, fern, etc.), oak, sawtooth oak, maple, sequoia, metasequoia, cypress, red-crested wrinkle, takanotsume, amacha, Akebia, Japanese berry, Ryuba, Tamushiba, Kobushi, Japanese argillacea, Shiromoji, Kuromoji, Koshiabura, Kusagi, Magnolia, Actinidia

, Banaba, Rooibos, Rafuma, Kudzu, Megusurinoki, Urin, Merbao, Aogiri, Suou, Brazilwood, Melinjo, Sakura, Magnolia, Yerba

Yerba mate, manhirugi, hirugi, Yaeyama hirugi, pomegranate, nipa palm, mangrove mangrove, mandarin orange, sakishimasu, burdock, turmeric, lotus root, seaweed (seaweed, wakame seaweed, kelp, sea lettuce, arame, sargassum, etc.).

[0023] Among these, grapes, coffee (coffee tree), tea (tea), cacao, acacia, cedar, mat, yuzu, lemon, herbs (lavender, mint, coriander, cumin, sage, perilla, lemongrass, Mugwort, Comfrey, Lemon Balm, Oregano, Cat Tonip, Common Thyme, Dill

, dark opal, basil, hyssop, peppermint, lamb's ear, etc.)

, Houttuynia cordata, marigolds, sugar cane, mangoes, bananas, papaya, avocados, apples, cherries (cherries), guava, olives, potatoes (sweet potatoes, purple potatoes (sweet potatoes containing a lot of purple pigment), potatoes, yams

Taro (taro, shrimp, etc.), konjac, etc.), persimmon, mulberry, blueberry, poplar, ginkgo, chrysanthemum, sunflower, and bamboo are preferably used. [0024I"Processed products" include dried plants, juices, extracts, extracts and the like containing polyphenols and ascorbic acid. In addition, the squeezed juice or the extract may be further dried.

[0025] As the "dry matter", it is desirable to subject it to crushing, pulverization, pulverization, or other processing. In addition, considering the efficiency of reaction with iron, it is preferable to use a powder with a small particle size.

As the extraction solvent for the "extract" and "extract", water is suitable for ascorbic acid, and water, hot water, alcohol (especially ethanol), hydrous alcohol (especially hydrous alcohol) is suitable for polyphenols. ethanol) is preferred.

[0026] As a feedstock for the reducing organic matter, the residue remaining after extracting the plant body or its processed product with water or hot water can also be suitably used. A dry distillation solution obtained by thermally decomposing a plant or its processed product in a reducing state (plant dry distillation solution) can also be preferably used.

[0027] Plant-derived raw materials with advantageous raw material costs In the present embodiment, fruit juice, stem and leaf juice, plant dry distillation, roasted coffee beans, and tea leaves are used as raw materials for supplying reducing organic matter. As a result, it becomes possible to manufacture the photocatalyst at a lower cost, and an economically advantageous effect can be expected.

(a) Fruit Squeezed Liquid [0028] As the raw material for supplying the reducing organic matter, it is preferable to use a "fruit squeezed liquid". As the type of fruit used for squeezing the fruit juice, the above-mentioned fruit can be preferably used. In particular, those having a large total polyphenol content are preferable in terms of their potency. In addition, from the viewpoint of raw material costs, it is preferable to use squeezed juices of grapes, bananas, apples, persimmons, tomatoes, citrus fruits, and the like.

(b) Squeezed juice of stems and leaves It is preferable to use "squeezed juice of stems and leaves" as the feedstock of the reducing organic matter. As the type of plant used for the foliage squeezing, the foliage of the plant body described above can be preferably used. In particular, those with a large amount of total polyphenols are preferred in terms of potency. suitable. In addition, from the viewpoint of raw material costs, it is preferable to use juices from horsetail, cypress, mac, cedar, and the like.

(c) Plant Dry Distillate [0030] As the feedstock for the reducing organic matter, it is preferable to use a "plant dry distillation solution". In addition to containing a large amount of polyphenols, the raw material contains many molecules of reducing organic substances such as phenols, organic acids, carbonyls, alcohols, amines, basic components, and other neutral components. Presumed to be included.

[0031] Here, the plant dry distillation solution refers to a dry distillation solution (sticky brown liquid) obtained by thermally decomposing a reduced plant body. Appearance is reddish brown to dark brown. The undiluted solution can be used as it is, but it can also be used as a concentrated solution, a diluted solution, or a dried product thereof. Specific examples of the dry distillation of the plant include wood vinegar, bamboo vinegar, rice vinegar, and the like. These can be preferably used from the viewpoint of raw material cost.

(d) Roasted coffee beans [0032] It is preferable to use raw materials derived from "roasted coffee beans" as the feedstock for the reducing organic matter. This raw material contains a very large amount of polyphenols. In this embodiment, the roasted coffee beans can be used as they are or after being pulverized. Also, a component obtained by extracting the pulverized product with water or hot water (so-called brewed coffee component) can be used. Also, the residue after extraction with water or hot water (so-called coffee grounds) can be used. In particular, from the viewpoint of raw material cost, it is most suitable to use "coffee grounds", which are discarded in large quantities after the extraction of coffee components.

[0033] Here, the roasted coffee beans include any roasted coffee beans according to a normal method. The state of so-called ground (crushed) coffee beans is also included here. Moreover, it may be one obtained by roasting ground coffee beans. Here, coffee beans include Coffea arab i ca (Arabica), C. canephora (Robusta), C. L i ber i ca (Libera). Velica species) seeds can be used. Although fresh coffee beans may be used, dried and preserved coffee beans that are commonly used are preferred. Industrially, it is preferable to use non-standard coffee beans from the viewpoint of raw material costs. Here, the roasting can be any method commonly used, for example, direct fire roasting, hot air roasting, far infrared ray roasting, microwave roasting, heated steam roasting, low temperature roasting, etc. can be mentioned.

[0034I In addition, pulverization is, for example, a state in which normal coffee beans are ground by a coffee mill, a grinder, a millstone, etc., and includes a wide range of grounds from coarse ground to powdered. Considering the efficiency of reaction with iron, it is preferable to have a state with a large surface area, so it is preferable to crush, pulverize, powderize, or the like.

(d) Tea leaves [0035] As the feedstock for the reducing organic matter, it is preferable to use a material derived from "tea leaves". This raw material contains a very large amount of polyphenols. In this embodiment, the tea leaves can be used as they are or after being pulverized. Also, a component obtained by extracting the pulverized product with water or hot water (so-called brewed tea component) can be used. Moreover, the residue after extraction with water or hot water (so-called used tea leaves) can be used. In particular, from the viewpoint of raw material costs, it is most suitable to use "used tea leaves" that are discarded in large quantities after the extraction of tea components.

[0036] Here, as the tea leaves, any leaf can be used as long as it is obtained by picking the stems and leaves of Camellia sinensis, which is a tea tree. Any picking method may be used, but mechanical picking is particularly preferable from the viewpoint of cost. In the present invention, tea leaves at any stage of fermentation can be used, although plucked tea leaves are mixed with cell contents and oxidized and fermented. For example, green tea that has been heated to suppress oxidative fermentation (sencha, bancha, stem tea, hojicha, etc.), green tea that has been fermented to some extent (oolong tea, etc.), black tea that has been fermented completely, and koji mold fermentation after oxidative fermentation. Black tea (such as pu-erh tea), etc. can be used. Green tea, black tea, and oolong tea are preferred. In addition, the raw material Industrially, it is preferable to use non-standard tea leaves from the standpoint of the strike. In addition, considering the reaction efficiency with iron, it is preferable to have a large surface area, so it is preferable to use it after crushing, pulverizing, pulverizing, or the like.

[0037I] Only one type of the above-mentioned reducing organic feedstock can be used, or two or more types can be used in combination.

[0038] Further, a reducing gas can be used as a raw material for supplying carbon. Examples of the reducing gas include carbon monoxide (Co), hydrocarbon gases (hydrogen (H2), methane (CHQ, propane ( _C3HQ , butane ( _C4H10 ), etc.), and the like. In addition, by using such a reducing gas, it becomes possible to manufacture a photocatalyst composition under an appropriate reducing atmosphere in the method for manufacturing a photocatalyst composition described below.

[Iron feedstock] [0039] The photocatalyst composition of the present embodiment contains at least one of a divalent iron feedstock and a trivalent iron feedstock as a feedstock for supplying elemental iron. In addition, as a raw material for supplying the iron element, a raw material for supplying metallic iron can also be used. Moreover, a plurality of substances can be mixed and used.

[0040] Here, the "ferric compound (supply material of divalent iron)" includes iron chloride (IDs iron nitrate (II), iron sulfate (IDs iron hydroxide (II), iron oxide (II), iron (II) acetate, iron lactate (

II), water-soluble iron compounds such as sodium iron (II) citrate and iron (II) gluconate; and insoluble divalent iron compounds such as iron (II) carbonate and iron (II) fumarate.

[0041] As the "ferric feedstock", iron chloride (Ill)s iron sulfate (Ill)s iron citrate (

III), water-soluble trivalent iron compounds such as ammonium iron (III) citrate, iron (III) EDTA; iron oxide (Ill)s iron nitrate (Ill)s iron hydroxide (Ill)s iron pyrophosphate Insoluble trivalent iron compounds such as (III) can be mentioned.

[0042] Natural raw materials containing a large amount of these trivalent iron compounds include Akadama soil, Kanuma soil, loam (soil containing a lot of allophane iron), laterite (iron oxide (II

I) rich soils), goethites (soils containing amorphous minerals); natural iron ores such as pyrite, marcasite, siderite, magnetite, goethite; iron sand, which is sanded iron ore; heme iron, bio-derived substances such as shells; and the like.

[0043I In addition, the "supply material of metallic iron" includes iron materials such as smelted iron and alloys. In addition, gold rust can also be used as a “supply material for metallic iron”.

[0044] Furthermore, as the "iron feedstock", a reaction product obtained by mixing a reducing organic substance having iron-reducing ability or a feedstock thereof with an iron feedstock in the presence of water is used. can also More specifically, for example, as an "iron feedstock", a polyphenol or its feedstock and an iron feedstock are mixed in the presence of water, and the resulting polyphenol iron complex (ferric ion ( Fe 2+) forming a complex structure with polyphenols) is preferably mentioned.

[0045] Even if the above iron feedstock is water-insoluble, it can be used directly as an iron feedstock because it is water-soluble due to the chelating ability of the reducing organic matter. Also, an aqueous solution containing divalent iron ions and/or trivalent iron ions in which the iron compound is dissolved in water can be used.

[0046] Of the above iron feedstocks, it is preferable to use a water-soluble divalent iron compound or trivalent iron compound in order to efficiently produce a photocatalyst composition. In particular, it is preferable to use inexpensive iron chloride, iron sulfate, or the like. In addition, in order to produce iron from the viewpoint of raw material cost and stable supply, it is preferable to use natural soil (especially Akadama soil, Kanuma soil, loam, etc.) and metallic iron as iron supply raw materials. .

[Glass material] [0047] The photocatalyst composition of the present embodiment contains a raw material for supplying silicon (silicon feed raw material) as a glass material. In addition, as the glass material, it is possible to use known glass materials that are commonly used in the production of glass and ceramics. For example, as the glass material, materials commonly used for manufacturing silicate glass (soda lime glass, borosilicate glass, quartz glass, lead glass, etc.) can be used. [0048I The "silicon feedstock" includes plants selected from grasses, ferns, and algae, and processed products of such plants. The gramineous plants include rice, rush, sugar cane, rush, bamboo, wheat, barley, corn, oat, turfgrass, sorghum, rye, foxtail millet, elephant grass, pampas grass, bamboo grass, and the like. Examples of fern plants include horsetail and horsetail. Examples of algae include diatoms (especially Chaetoceros).

[0049I] Among these, it is preferable to use rice and sugarcane, and it is most preferable to use rice husks, rice leaves, and sugarcane leaves, which are often produced as by-products in the agricultural industry. By using such a by-product, it is possible to produce a photocatalyst at low cost, and an economically advantageous effect can be expected.

[0050I"Processed products" include dried products of the above-described silicon-containing plant bodies, juices, extracts, extracts, dried products of squeezed juices and extracts, and the like. The dried matter, juice, extract, and liquid extract can be obtained by the same treatments as those of the above-described reducing organic matter.

[0051] In addition to the above plant body or processed product, silicate, silicon, silicon dioxide (silica), silicon chloride, silica sand, glass (recycled glass), etc. can be used as "silicon feedstock". can. It is also preferable to use a combination of these silicon feedstocks.

[0052] Glass materials other than silicon feedstocks include, for example, boron, boron oxide, sodium borate (particularly sodium tetraborate), soda ash, anhydrous sodium carbonate, limestone, calcium carbonate, potassium carbonate, and the like. include, but are not limited to: In addition, stabilizers and coloring materials for enhancing decorativeness and the like can be added to these glass materials.

[0053] A preferred mixing ratio of the raw materials will be described. The mixing ratio of the reducing organic matter and the iron feedstock is as follows: 0.1 part by weight of the iron feedstock in terms of the weight of the iron element per 100 parts by weight of the dry weight of the reducing organic matter or the feedstock of the reducing organic matter. Above, preferably 0.5 parts by weight or more, more preferably 1 part by weight or more, still more preferably 2 parts by weight It may be blended so as to contain at least 3 parts by weight, particularly preferably at least 3 parts by weight, and more preferably at least 4 parts by weight. If the ratio of iron element is too low (the mixing ratio of reducing organic matter to iron element is too high), the excess reducing organic matter functions as a radical scavenging substance (scavenger), resulting in photocatalytic activity. ○

[0054J In addition, the upper limit of the amount of iron element is 10 parts by weight or less, preferably 8 parts by weight or less, and more preferably 6 parts by weight or less in terms of the weight of iron element. If the ratio of the iron element is too high (the mixing ratio of the reducing organic substance is too low relative to the iron element), the iron ions cannot be maintained in a bivalent state, resulting in a decrease in photocatalytic activity, which is not preferable.

[0055] On the other hand, the mixing ratio of the reducing organic substance and the silicon feedstock is

or 5 parts by weight or more, preferably 10 parts by weight or more, more preferably 10 parts by weight or more of the silicon feedstock in terms of the weight of the element, per 100 parts by weight in total of the feedstock of the reducible organic matter (dry weight) and the iron feedstock. is 50 parts by weight or more, more preferably 60 parts by weight or more, and particularly preferably 90 parts by weight or more. If the ratio of the silicon element is too low (the mixing ratio of the reducing organic substance is too high with respect to the silicon element), glass-ceramics will not be formed, which is not desirable.

〇

[0056] The upper limit of the amount of silicon element is 99 parts by weight or less, preferably 60 parts by weight or less, and more preferably 30 parts by weight or less in terms of the weight of silicon element. If the proportion of the silicon element is too high (the mixing proportion of the reducing organic substance is too low relative to the silicon element), glass-ceramics will not be formed, which is not preferable. The silicon feedstock (dry weight) is preferably 100 parts by weight or more with respect to a total of 100 parts by weight of the reducing organic substance or the feedstock of the reducing organic substance (dry weight) and the iron feedstock. , more preferably 200 parts by weight or more, more preferably about 300 parts by weight.

[0057] A plant extract or In the case of using an extract, the dry weight of the plant body used as the raw material for extraction should be regarded as the "dry weight of the raw material for reducing organic matter" to calculate the mixing ratio. For example, it is assumed that dry tea leaves are used as a feedstock of reducing organic matter, and an extract obtained by hot water extraction of the tea leaves is reacted with an iron feedstock. In this case, the weight of the dry tea leaves is used as the "dry weight of the reducing organic feedstock" to calculate the mixing ratio with the iron feedstock.

[0058I] By the way, as described above, the inventors mixed a reducing organic substance as a photocatalyst with an iron feedstock in the presence of water, and obtained a reaction product, more specifically, polyphenols and , developed a polyphenol iron complex obtained by mixing with an iron feedstock in the presence of water. Although this polyphenol iron complex exhibits a photocatalytic effect against visible light, its stability (sustainability) is a problem. In solving this problem, the inventors considered that the carbon in the polyphenol iron complex receives electrons from the light and transfers them to the divalent iron, thereby stabilizing the divalent iron in that state. Therefore, we thought that a stable photocatalyst could be obtained by combining carbon and divalent iron to increase the stability of the polyphenol iron complex. However, it is difficult to bond divalent iron and carbon, and as a result of examining the reaction under various conditions, when glass was produced using polyphenols and an iron supply source, it was found that carbon and iron could be bonded. was made. Furthermore, they found that the silicon contained in the glass material enhances the stability as a photocatalyst. A method for producing the photocatalyst composition of the present embodiment will be described below.

(Method for Producing Photocatalyst Composition) [0059] In the method for producing a photocatalyst composition of the present embodiment, a reducing organic substance having an action of reducing trivalent iron to divalent iron, an iron feedstock, and a glass material are used. A step (heating step) of heat-treating the mixed mixture in a reducing atmosphere at a heating temperature of 900° C. or higher for a heating time of 12 minutes or longer is included. This heating process (more specifically, the reduction firing process

), the raw material can be melted appropriately to improve the quality of the glass, and the bonding between carbon and ferrous iron can be improved, resulting in a photocatalyst composition having stable photocatalytic activity. you get something. [0060I The heating temperature may be 90°C or higher, but 120°C or higher. A temperature of 0°C or less is more preferable. The heating time may be 12 minutes or longer, more preferably 12 minutes or longer and 12 hours or shorter, and even more preferably 12 minutes or longer and 3 hours or shorter. The heating temperature should be about 20 minutes (0.33 hours) in consideration of the molten state and work efficiency. By performing the heating process at such a temperature and time, the raw material is melted more appropriately, crystallization is promoted, and the quality as glass is improved, and the bonding between carbon and ferrous iron is improved. As a result, a photocatalyst composition having more stable photocatalytic activity can be obtained.

[0061] In addition, the heating step can be performed in a reducing atmosphere to enhance the effect of reducing trivalent iron, which is a reducible organic substance, to divalent iron. By heating, the reducing organic matter is carbonized to generate carbon dioxide, and the heating process can be performed in a reducing atmosphere. The action can be made more appropriate.

[0062] In addition to the heating step, a mixing step, a cooling step, a pulverizing step, and the like are included. The mixing step is a step of charging a glass material containing a predetermined mixing ratio of a reducible organic substance, an iron feedstock, and a silicon feedstock into a container such as a crucible and mixing them. The cooling step is a step of appropriately cooling and vitrifying the melt obtained in the heating step. This cooling step vitrifies the melt to produce a photocatalyst composition composed of glass or glass-ceramics. Through this cooling step, plate-like or block-like glass or glass-ceramics (hereinafter referred to as "plate glass" or "glass block") are obtained. This plate glass or glass lump can be used as a photocatalyst composition as it is, or can be divided into appropriate sizes and used as a photocatalyst composition. In such a photocatalyst composition, a bond (reaction product) of carbon and ferrous iron having photocatalytic activity is scattered inside and on the surface, and a photocatalytic reaction is caused by the reaction product on the surface of the photocatalyst composition. occurs. In addition, even when the surface of the photocatalytic composition is scraped off, a photocatalytic reaction occurs due to the reaction products present on the newly exposed surface, so excellent photocatalytic activity can be maintained.

[0063] Further, a pulverized product obtained by pulverizing a plate glass or a glass lump by a pulverizing process can also be used as a photocatalyst composition. In this pulverization step, a plate glass or a lump of glass is manually pulverized using a hammer, mortar, or the like, or by using a device such as a pulverizer or a bead mill to obtain a pulverized product. Examples of the form of the pulverized product include beads, granules, and powder. In the photocatalyst composition pulverized in this way, the increased surface area increases the contact with organic substances to be decomposed and microorganisms to be sterilized, and the photocatalytic activity can be further improved.

[0064I FIG. 1 is a flow chart showing a preferred example of the process for producing the photocatalyst composition of the present embodiment. As shown in FIG. 1, the photocatalyst composition of the present embodiment includes a mixing step, a heating step, a cooling step, and a pulverizing step, but may include other steps necessary for glass production.

[0065] The form of the photocatalyst composition of the present embodiment may be plate glass, glass lumps, beads, granules, or pulverized powder. can do. Also, multiple forms of the photocatalyst composition can be used in combination.

[0066] The shape of the photocatalyst composition of the present embodiment, for example, in the case of plate glass, is preferably a quadrangle, but may include a triangle, a polygon with pentagons or more, a circle, an oval, a star, and a heart. , and other shapes that enhance decorativeness and taste. In this case, the size (outer diameter) is preferably 1 mm or more and 50 mm or less. In addition, in the case of glass lumps and pulverized materials, spherical, spheroidal, columnar, prismatic, conical, and pyramidal shapes may be mentioned, but irregular shapes may also be used. In this case, the size is preferably 1 mm or more and 50 mm or less. In the case of powder, the shape is not particularly limited, and the size (particle diameter) is preferably an average particle diameter of 0.1 mm or more and 5 mm or less. Here, "average particle size" refers to the particle size at an integrated value of 50% in the particle size distribution obtained by the laser diffraction/scattering method.

[0067] The photocatalytic composition of the present embodiment produced by the above production method has excellent photocatalytic activity and excellent stability capable of maintaining this excellent photocatalytic activity for a long period of time. In this photocatalyst composition, it is presumed that the carbon derived from the reducing organic substance makes the iron ion into a divalent state (Fe2+ state) to form a complex. again, It is speculated that silicon in the silicon feedstock enhances the bonding between carbon and iron and increases the stability as a photocatalyst.

[0068I] The photocatalyst composition of the present embodiment absorbs sunlight and light in a wide wavelength range of 200 to 1400 nm, that is, when irradiated with not only ultraviolet light but also visible light and infrared light. It has the property of exhibiting excellent photocatalytic activity.

[0069] Here, "ultraviolet rays" refer to light in a wavelength range of 380 nm or less. Also, “visible light J” refers to light with a wavelength of 380 to 750 nm, which is the wavelength range visible to the human eye. Specifically, “visible light” includes 380 nm to 450 nm (violet light), blue light), 495 nm to 570 nm (green light), 570 nm to 590 nm (yellow light), 590 nm to 620 nm (orange light), and 620 nm to 750 nm (red light). In addition, "infrared" refers to light in a wavelength range of 750 nm or more.

[0070] Above all, this photocatalytic composition exhibits extremely strong photocatalytic activity (bactericidal action) when irradiated with ultraviolet rays. In particular, the strength of its activity in light with a wavelength of 200 nm to 380 nm, which is near-ultraviolet, shows far greater photocatalytic activity than that of titanium oxide.

[0071] In addition, the photocatalytic composition of the present embodiment exhibits strong photocatalytic activity even when irradiated with visible light and infrared light, which are wavelength regions in which titanium oxide does not exhibit activity. This photocatalyst composition exhibits strong activity in the wavelength region of violet light to blue light (380 to 495 nm), which has a particularly short wavelength, in visible light. This photocatalyst composition exhibits strong activity in the near-infrared wavelength range of 750 to 1400 nm (particularly around 900 to 1300 nm, more particularly around 1100 to 1300 nm), which is near infrared rays.

[0072] The light with which the photocatalyst composition of the present embodiment is irradiated includes natural light (sunlight) including visible light, ultraviolet rays, infrared rays, and the like, and illumination light that irradiates light of a predetermined wavelength. . For example, under sunlight, the photocatalytic activity of the photocatalytic composition can be observed, and organic matter can be decomposed and sterilized in a few seconds. In addition, as the illumination light, white LED light from a white LED light source is preferable, and is suitable for indoor use. It is possible to further enhance the organic substance decomposition effect and the sterilization effect.

[0073] The photocatalyst composition of the present embodiment absorbs irradiated light energy, shows activity to decompose organic substances. The activity is presumed to be a phenomenon brought about by radicals generated by a photocatalyst excited by light energy.

[0074I] The photocatalyst composition of the present embodiment has a property of continuously exhibiting photocatalytic activity during continuous irradiation with light. In addition, even when light irradiation is interrupted once, this photocatalyst composition exhibits photocatalytic activity upon re-irradiation. That is, this photocatalyst composition is a material that can be used repeatedly as a photocatalyst. This is because the resonance structure in the molecule of the reaction product (the Fe2 + complex of the reducing organic substance) transmits light energy to Fe2 + to efficiently generate radicals, and the molecules themselves are not attacked by the radicals. It is presumed that this is because the structure is stable and scavenges by the resonance structure even if it is subjected to radiation. In addition, it is presumed that the silicon feedstock increases the bonding between carbon and iron, increasing the stability as a photocatalyst.

[0075I] The photocatalyst composition of the present embodiment does not use titanium or the like and has less impact on the human body and the environment. be able to. That is, ascorbic acid and polyphenols are used as reducing organic substances, and since these are substances derived from food-derived feedstocks, they are expected to be used particularly in the food field. Ascorbic acid is particularly suitable because it is colorless and transparent. In addition, when a plant dry distillation solution is used as a reducing organic substance feedstock, the component contains a substance having a slight odor. However, since the raw material is very inexpensive, it is expected to be used in fields such as agriculture, medicine, and public health.

[0076I In addition, in the photocatalyst composition of the present embodiment, the glass material contains a silicon feedstock consisting of a plant body selected from gramineous plants, fern plants, and algae, or a processed product of the plant body. do. From this, the photocatalyst composition of the present embodiment can be used in various applications such as medicine, food, public health, agriculture, industry, etc., and the bonding between carbon and divalent iron is enhanced by silicon. It is possible to provide an enhanced and stable photocatalyst composition. In addition, as a silicon feedstock, it contains a large amount of silicic acid. It is expected to lead to research exploring these new possibilities, as plants of the grass family, ferns, algae, etc. are used. In addition, by utilizing plant resources, the effects on the human body and the environment can be suppressed, raw materials are inexpensive, waste can be reduced, and photocatalyst compositions with high added value can be provided.

[0077I] The photocatalyst composition of the present embodiment has the property of exhibiting activity when irradiated with not only ultraviolet light but also visible light and infrared light. As a result, the photocatalyst composition of the present embodiment is expected to be used in various applications in which conventional titanium oxide was difficult to use. For example, it can be used in a normal indoor space or in a liquid placed in a room (such as water in a container such as a vase or aquarium).

(Organic substance decomposing agent, bactericidal agent, deodorant) [0078] The photocatalyst composition of the present embodiment has excellent photocatalytic activity and excellent stability, and therefore can be used as an organic matter decomposing agent, bactericidal agent, and deodorant. It can be suitably used as an agent. Each is described below.

(Organic Matter Decomposing Agent) [0079] The organic matter decomposing agent of the present embodiment contains the photocatalyst composition exhibiting catalytic activity under visible light. Therefore, the organic substance decomposing agent of the present embodiment has excellent photocatalytic activity with respect to light of a wide range of wavelengths including visible light, and has excellent stability, and can be used for decomposing various organic substances. . In particular, this photocatalyst composition can be suitably used for decomposing organic pollutants and harmful substances, and is therefore useful in the process of environmental purification.

[0080] Here, pollutants and harmful substances refer to substances that cause water pollution, soil pollution, and air pollution. Examples include organic substances that affect the human body and the environment contained in domestic wastewater, night soil water, industrial wastewater, polluted river and lake water, soil of garbage disposal sites, industrial waste, agricultural land, and abandoned factory sites. be done.

[0081] Specific organic substances to be decomposed include, for example, detergents, food and drink residues, night soil, feces, pesticides, malodorous substances, waste oils, dioxins, PCBs, DNA, RNA, proteins, and other organic wastes. etc.

[0082] Since the organic substance decomposing agent of the present embodiment has an extremely strong decomposing effect, It can efficiently decompose soluble organic substances (eg, basic fuchsin). For example, when irradiating with light of 100 W/m ₂ , it is possible to decompose organic matter at least 2.5 mg/L or more per day, and at most 35 mg/L or more.

(Bactericidal agent) [0083] The bactericidal agent of the present embodiment contains the above-described photocatalyst composition that exhibits catalytic activity under visible light. Therefore, the sterilizing agent of the present embodiment has excellent photocatalytic activity with respect to light of a wide range of wavelengths including visible light, and has excellent stability, and can be used for sterilizing various things. Specifically, the objects to be sterilized include medical instruments, hospital room walls, affected areas of patients, clothes, bedding, etc., lines of food manufacturing equipment, foodstuffs, cutting boards, kitchen utensils such as kitchen knives, tableware, toilet seats, handrails, etc. Agricultural equipment, equipment for hydroponics, and hydroponics. The sterilizing agent of the present embodiment can be used for irradiation with visible light and infrared rays, unlike the normal sterilizing method using titanium oxide, so that the usage and usage situations are greatly improved. Moreover, the disinfectant of the present embodiment can disinfect not only bacteria but also eukaryotic microorganisms, algae, archaebacteria, viruses, viroids, and the like.

[0084I] Since the bactericidal agent of the present embodiment has an extremely strong bactericidal effect, for example, in the case of surface sterilization, it is treated with sunlight irradiation for several minutes, preferably 10 minutes or more, more preferably 20 minutes or more. , + minute sterilization effect is obtained. In addition, even when relatively weak light such as LED or fluorescent lamp is irradiated, a sufficient sterilization effect can be obtained by treatment for 1 hour or more, preferably 6 hours or more, more preferably 12 hours or more.

(Deodorant) [0085] The deodorant of the present embodiment contains the above-described photocatalyst composition exhibiting catalytic activity under visible light. As described above, the photocatalyst composition of the present embodiment has excellent organic substance decomposition effect and bactericidal effect, so that it is possible to suppress the generation of organic substance odors and odors caused by microbial decomposition of organic substances.

[0086] Therefore, the deodorant of the present embodiment can be used to deodorize various odors. In particular, it can exert an excellent deodorizing action against the odors generated by organic substances as mentioned in the explanation of the organic substance decomposing agent. Also, as mentioned in the description of the disinfectant above, It is possible to satisfactorily suppress the generation of odors due to the decomposition of organic matter by microorganisms such as [0087I As described above, when the photocatalyst composition of the present embodiment is used as an organic substance decomposing agent, a disinfectant, or a deodorant, examples thereof include plate glass and glass lumps. , beads, granules, and pulverized powders. The organic substance decomposing agent, sterilizing agent, or deodorant in such a form is placed in a gas or liquid to be decomposed, sterilized, or deodorized as it is or stored in a container, and exposed to light. By irradiating, organic matter decomposition, sterilization, and deodorant effects are exhibited. It can also be used as a coating agent containing a photocatalyst composition in the form of pulverized particles such as beads, granules, or powder.

(Use in hydrogen production method) The photocatalyst composition of the present embodiment has excellent photocatalytic activity and excellent stability, and thus can be suitably used in a hydrogen production method. Due to the strong photocatalytic activity of the photocatalytic composition, water can be oxidatively decomposed into oxygen and hydrogen. That is, according to the present disclosure, there is provided a method for producing hydrogen, which includes the step of oxidatively decomposing water to generate hydrogen using the photocatalyst composition. When the photocatalyst composition of the present embodiment is used in a method for producing hydrogen, the forms thereof include, for example, plate glass and glass lumps, and further include bead-like, granular, and powdery pulverized products. . Hydrogen can be generated by irradiating the photocatalyst composition in such a form as it is or in a container or the like, placing it in water, and irradiating it with light. Example 1

[0088I] Hereinafter, the present disclosure will be specifically described with reference to examples, but the present disclosure is not limited to the following examples.

(Example 1) Production example of the photocatalyst composition of Example 1

[material] [table 1 ]

[0090] [Manufacturing process] The raw materials in Table 1 above were charged into a crucible, and then heated to ^12000C- using a return high-pressure burner.

At 130°C, the raw material was heated in a reducing atmosphere until it melted to produce a photocatalyst composition made of plate glass. The heating time was about 20 minutes. Tea leaves (reducing organic matter feedstock) used tea lees (residue of tea leaves extracted with boiling water), and iron salt (iron feedstock) used ferric chloride (III) (FeCL ₃₎ , a trivalent iron compound. . The mixing ratio of the tea leaves and the iron salt is 100 parts by weight of the tea leaves (converted to dry weight) to 100 parts by weight of iron salt in terms of iron element.

4 parts by weight. Rice husk was used as silicon feedstock. The mixing ratio of tea leaves + iron and rice husks was 100 parts by weight of rice husks (30 parts by weight or more in terms of silicon element) per 100 parts by weight of tea leaves + iron salt (converted to dry weight).

[0091 I The melt obtained in the above step was cooled by standing to produce a plate-like photocatalyst composition (plate glass). Next, the photocatalyst composition composed of this sheet glass was pulverized to produce a powdered photocatalyst composition (powder glass) of Example 1. FIG. 2(a) shows a photographic image of the photocatalyst composition (plate glass) before pulverization, and FIG. 2(b) shows a photographic image of the photocatalyst composition (powder glass) of Example 1 after pulverization. .

(Example 2) [0092] Glass beads were produced according to the mixing ratio of the raw materials and the production method as described in Example 1 above, and the bead-like photocatalyst composition of Example 2 was obtained.

[0093] The mixing ratio of the raw materials of the photocatalyst composition (mixture amount of each raw material) when rice husk is used as the silicon feedstock may be within the range shown in Table 2 below. A mixing ratio as in Example 2 is most preferable, and a photocatalyst composition having excellent quality as glass and excellent photocatalytic activity can be obtained.

[Table 2]

(Example 3) [0094] A photocatalyst composition of Example 3 was produced using sugarcane leaf ash as a silicon feedstock. The raw materials are shown in Table 3 below. The manufacturing process of the photocatalyst composition of Example 3 is the same as the manufacturing process in Example 1.

[material] [Table 3]

(Example 4) [0095] A photocatalyst composition of Example 4 was produced using ascorbic acid as a reducing organic feedstock. The raw materials are shown in Table 4 below. Ascorbic acid and iron salt were mixed at a ratio of 1:1 (1 g of ascorbic acid + 1 g of iron salt). The manufacturing process of the photocatalyst composition of Example 4 is the same as the manufacturing process of Example 1.

[material]

[Table 4]

[0096] Using the powdered photocatalyst composition of Example 1 and the beaded photocatalyst composition of Example 2, the following performance verification experiments and component analysis were performed. Figure 3 shows the optical spectrum distribution of the white LED light source used in each experiment. According to FIG. 3, it can be seen that the white LED light contains visible light of 380 to 750 nm.

[Analysis of component composition] [0097] The component composition of the photocatalyst composition of Example 1 was analyzed by the analysis method shown in Table 5 below. Similarly, the photocatalysts of Reference Examples 1 and 2 were subjected to component analysis. The analysis results are shown in Table 5 below. The numerical values in Table 5 below are for the photocatalyst composition or polyphenylene. The content (% by weight) of each component in the nor-iron complex is shown.

[0098I As a photocatalyst in Reference Example 1, an aqueous solution containing used tea leaves and iron (III) chloride (the mixing ratio is the same as in Example 1) was prepared, allowed to stand at room temperature for several minutes, and polyphenolic iron derived from used tea leaves A complex was obtained. In addition, as a photocatalyst of Reference Example 2, an aqueous solution containing coffee grounds and iron (III) chloride (the mixing ratio is the same as in Example 1) was prepared and allowed to stand at room temperature for several minutes to produce a polyphenol iron complex derived from coffee grounds. Obtained.

[0099] [Table 5]

Analysis method:

ICP emission spectroscopy, dipyridyl reaction analysis, oxygen circulation combustion method, X-ray photoelectric spectroscopy (XPS: X-ray Photoe Lectron Spectroscopy or ESCA: Electron Spectroscopy for Chemical Analysis )

[Experimental Example 1: Verification Experiment of Iron-Reducing Ability] [0100] The powdery photocatalyst composition of Example 1 was subjected to an iron-reducing ability verification experiment by dipyridyl reaction analysis. Specifically, dipyridyl and acetic acid were added and mixed to the photocatalyst composition so that dipyridyl was 2 g/L and acetic acid was 100 g/L, and the presence or absence of color reaction was examined.

[0101] Here, dipyridyl is a substance that does not react with trivalent iron and remains colorless, but turns red when it reacts with divalent iron. Used for detection of divalent iron * As a result, the solution containing the powdered photocatalyst composition of Example 1 exhibited a red color. That is, the trivalent iron added as a raw material of the photocatalyst composition is It was shown that it was reduced to divalent iron by heating in air (reduction firing). It was also shown that the ferrous iron reduced here is stably maintained in the state of ferric iron. FIG. 2(c) shows a photographic image of the powdery photocatalyst composition of Example 1 dyed with dipyridyl to give a red color.

[0102] [Experimental Example 2: Effect of decomposing harmful substances of photocatalyst composition by irradiation with white LED light] In order to verify the effect of decomposing harmful substances of the photocatalyst composition of Example 1 by photocatalytic reaction, visible light was used. A decomposition experiment of methylene blue was performed using white LED light.

Experimental method: 10 mg of the powdery photocatalyst composition of Example 1 was added to 10 ml of methylene blue solution (5000 ppm methylene blue solution diluted 1000 times with water to 5 ppm), and continuously exposed to white LED light ( 30,000 lux) was irradiated, and the decomposition rate of methylene blue was measured. At this time, 10"L of methylene blue solution was additionally added at regular intervals to repeat the decomposition. In addition, a similar experiment was performed using titanium oxide as a control group.

[0103] • Experimental results: Fig. 4(a) graphically shows the experimental results. The arrows in the graph of FIG. 4(a) indicate that 10 ML of methylene blue solution was additionally added. In addition, FIG. 4(b) shows a photographic image of the solution in the control section after the experiment, and FIG. 4(c) shows a photograph of the solution in the light-irradiated section of the photocatalyst composition of Example 1 after the experiment. An image diagram is shown.

[0104] As shown in Fig. 4(a), in the control group using titanium oxide, methylene blue did not decompose, and the addition of methylene blue increased the concentration. Also, as shown in the photographic image of FIG. 4(b), the solution in the control group remained methylene blue (blue). This is because titanium oxide does not exhibit a photocatalytic reaction with white LED light (visible light).

[0105] On the other hand, in the light irradiation section using the photocatalyst composition of Example 1, Fig. 4 (a

), even when methylene blue was added, the methylene blue was decomposed by continuous white LED irradiation, and the concentration decreased. In addition, as shown in the photographic image of Fig. 4(c), As shown, in the light irradiation section using the photocatalyst composition, the color of the solution became transparent, indicating that methylene blue was decomposed. Therefore, it was found that the photocatalyst composition of Example 1 exhibits a strong photocatalytic reaction to the light (visible light) of the white LED, and is excellent in decomposing harmful substances such as methylene blue.

[Experimental Example 3: Effect of photocatalyst composition on decomposing harmful substances by ultraviolet irradiation] [0106] In order to verify the effect of decomposing harmful substances by the photocatalytic reaction of the photocatalyst composition of Example 1, ultraviolet rays were used to decompose methylene blue. decomposition experiments were carried out.

Experimental method: An ultraviolet LED light source (see Fig. 5) was used as the light source, and a decomposition experiment of methylene blue was performed in the same manner as in Experimental Example 2 above (ultraviolet irradiation group). , A similar experiment was conducted in the titanium oxide section using titanium oxide. In the experiment, the concentrations of iron and titanium oxide in the photocatalyst composition were adjusted to be the same, and each was added to the methylene blue solution. Then, it was continuously irradiated with ultraviolet rays for 24 hours, and the decomposition of methylene blue was observed.

[0107] • Experimental results: Figure 5 shows a photographic image of the experimental results. In FIG. 5, (a) is a photographic image of the solution in the control section (no photocatalyst), and (b) is a photographic image of the solution in the ultraviolet irradiation section using the photocatalyst composition of Example 1. (c) is a photographic image of a solution of a titanium oxide group using titanium oxide. As shown in these figures, in the control group (a), the solution remained blue and methylene blue was not decomposed. On the other hand, in (b) the ultraviolet irradiation section using the photocatalyst composition of Example 1 and (c) the titanium oxide section, decomposition of methylene blue was observed. Therefore, it was found that the photocatalyst composition of Example 1 exhibits a strong photocatalytic reaction to ultraviolet rays and is excellent in decomposing harmful substances such as methylene blue.

[Experimental Example 4: Effect of photocatalyst composition on decomposing harmful substances by near-infrared irradiation] , carried out a decomposition experiment of methylene blue.

•experimental method : Using a near-infrared LED light source as a light source, a decomposition experiment of methylene blue was performed in the same manner as in Experimental Examples 2 and 3 (near-infrared irradiation section). A similar experiment was conducted with the titanium oxide used. In the experiment, the concentrations of iron and titanium oxide in the photocatalyst composition were adjusted to be the same, and each was added to the methylene blue solution. Next, near-infrared rays (1200 nm) were continuously irradiated for 5 days, and decomposition of methylene blue was observed.

[0109] • Experimental results: Figure 6 shows a photographic image of the experimental results. In FIG. 6, (a) is a photographic image of the control solution, (b) is a photographic image of the control solution using titanium oxide, and (c) is the photocatalyst composition of Example 1. FIG. 4 is a photographic image of a solution in a near-infrared irradiation section using a material. As shown in FIG. 6, in the control group (a) and the titanium oxide group (b), the solution remained blue and methylene blue was not decomposed. In contrast, decomposition of methylene blue was observed in the near-infrared irradiation section using the photocatalyst composition of Example 1 (c). Therefore, it was found that the photocatalyst composition of Example 1 exhibits a strong photocatalytic reaction to near-infrared rays and is excellent in decomposing harmful substances such as methylene blue.

[01 10] As described above, from the experimental results of Experimental Examples 2 to 4, the photocatalyst composition of Example 1 exhibits excellent photocatalytic activity against light in a wide wavelength range including ultraviolet light, visible light, and infrared light. It was confirmed that it has the property to exhibit. On the other hand, when titanium oxide was used, it was confirmed that photocatalytic activity was not exhibited with respect to visible light and near-infrared rays. Similar experiments were also conducted on the photocatalyst compositions of Examples 3 and 4, and it was found that they exhibit excellent photocatalytic activity with respect to light in a wide wavelength range including ultraviolet light, visible light, and infrared light. confirmed.

[01 1 1] [Experimental Example 5: Microbial sterilization effect] In order to verify the microbial sterilization effect of the photocatalytic reaction of the photocatalyst composition of Example 1, a pathogen sterilization experiment was conducted. Escherichia coli 0-157 (Escherichia co Li), which is a cause of contamination of cut vegetables, and Ra Lston ia O Lanacearum, which is a plant pathogen, were used as test microorganisms (pathogens). [0112] Experimental method:

It was placed in a tube and was continuously irradiated with a white LED (30,000 lux) for 30 minutes (light irradiation group). A "only zone" and a "dark condition zone" in which the photocatalyst composition was added but placed under dark conditions without irradiation with white LED light were provided. In addition, flow cytometry was used to measure the viability of each pathogen in each treatment plot.

[0113] • Experimental results: Fig. 7 shows a photographic image of each treated plot after treatment with E. coli. FIG. 7(a) shows the control group, ``light irradiation only treatment group'', FIG. 7(b) shows the ``dark condition group'' using the photocatalyst composition, which is the control group, and FIG. 7(c). indicates the “light irradiation section” using the photocatalyst composition.

[0114] Fig. 8 shows the results of determination of survival of E. coli by flow cytometry. Figure 8 (a) shows the result of determining whether E. coli is alive or dead in the "dark condition section" using the photocatalyst composition, which is the control group, and Figure 8 (b) shows the "light irradiation section" using the photocatalyst composition. shows the results of life-and-death determination of E. coli in . Fig. 9 shows the results of determination of life and death of R. wilt by flow cytometry. Fig. 9(a) shows the result of judging the survival of bacterial wilt bacteria in the "dark condition section" using the photocatalyst composition, which is the control group, and Fig. 9(b) shows the "photocatalyst composition" using the photocatalyst composition. Shown are the results of life-and-death determination of the bacterial wilt in the irradiated section.

[0115] As can be seen from Figs. 8 and 9, the survival of E. coli was confirmed in the "light irradiation only treatment area" and the "dark condition area", whereas the photocatalyst composition of Example 1 was used. It was confirmed that the E. coli was completely killed in the “light-irradiated area” where the white LED light irradiation was performed. In addition, as can be seen from each figure in FIG. 9, in the “light irradiation section” in which the photocatalyst composition of Example 1 was used to irradiate with white LED light, a high bactericidal effect against bacterial wilt was confirmed.

[0116] [Experimental Example 6: Identification Experiment of Radical Species by Luminol Reaction of Photocatalyst Composition

] For the photocatalyst composition of Example 1, radioactivity was detected by a luminescence method using luminol. Identification experiments of Cull species (detection of 〇2 and 〇2) were carried out.

■Experimental method Using the luminescence at 425 nm generated by the reaction between luminol and 〇2, this luminescence was detected by the photon counting method. By this method, the existence of •〇2 can be clarified.

[01 17] •Experimental results Figure 1 O shows the results of the identification experiment. As shown in this figure 1, the embodiment

A high luminol reaction was observed in the photocatalyst composition No. 1. Since luminol has the property of reacting with hydrogen peroxide in addition to 〇2, it was clarified that hydrogen peroxide was generated during the reaction. It was found that the number of photons (number of photons) decreased by adding a radical scavenger to this reaction solution.

[01 18] [Experimental Example 7: Identification experiment of superoxide radicals ( 〇厂) using MPEC reagent] For the photocatalyst composition of Example 1, superoxide radicals ( 〇〇) were identified using MPEC reagents. identification experiments were carried out.

■ Experimental method

The MPEC reagent is a luminescence reagent that specifically reacts with superoxide (・〇2-). We measured and confirmed the presence or absence of superoxide (・〇2”).

[01 19] •Experimental results Fig. 11 shows the results of the identification experiment. As shown in FIG. 11, generation of superoxide (·○2-) was observed by irradiating the photocatalyst composition of Example 1 with white LED light. It was found that the number of photons (number of photons) decreased by adding a superoxide radical scavenger to this reaction solution.

[Experimental Example 8: Hydroxyl Radical Identification Experiment by ESR Method Using Spin Trap] [0120] For the photocatalyst composition of Example 1, a hydroxyl radical identification experiment was performed by an ESR method using a spin trap. •Experimental method: 960 uL of distilled water was placed in an Eppendorf tube, and 20 mg of the photocatalyst composition of Example 1 was added. Furthermore, 180 mM spin trapping agent DMPO was added at 40/pound and irradiated with ultraviolet LED light (UV light) for 30 seconds, 60 seconds, and 30 minutes with an ESR device (Electron Spin Resonance). ESR spectra were measured. Furthermore, ESR analysis was performed on the reaction between the photocatalyst composition and white LED light (visible light).

[0121] Experimental results: Fig. 12 shows the results of the hydroxyl radical identification experiment by the ESR method using spin trap, showing the measurement results of the ESR spectrum by ultraviolet LED light irradiation ○ Fig. 13 shows white LED light irradiation ( The results of ESR analysis by visible light irradiation) are shown. Referenced (control group) in FIG. 13 is the ESR analysis result when the photocatalyst composition was not added. As shown in FIG. No generation was observed.On the other hand, the generation of hydroxyl radicals (-0H) was observed with ultraviolet irradiation for 30 minutes.In addition, as shown in FIG. ESR analysis of the reaction confirmed the detection of a hydroxyl radical ( • 0H).

[0122I In addition, ESR analysis revealed that in addition to hydroxyl radicals, methyl radicals (CH3) and carbon-centered radicals were also generated by the reaction with ultraviolet LED light (UV light). . Table 6 below shows the presence or absence of generation of radicals in the photocatalyst composition, polyphenol iron complex, and titanium oxide. In addition, as a control group, the same experiment was conducted with the polyphenol iron complex derived from used tea leaves of Reference Example 1 and with titanium oxide as a conventional example. In Table 6, ◯ indicates that radicals were generated, ◎ indicates that many radicals were generated, and X indicates that no radicals were generated.

[0123] [Table 6] Types of radicals detected by photoirradiation of each catalyst

[Experimental Example 9: Effect of preserving freshness of cut flowers (camellia)] [0124] An experiment was conducted to verify the effect of the photocatalyst composition of Example 2 on preserving the freshness of cut flowers.

Test flower: Camellia

•Experimental method: 100 ml of distilled water and 4 g of the bead-like photocatalyst composition of Example 2 were placed in a 200 ml beaker, and camellia flowers were made to float. This was continuously irradiated with white LED light (see the photographic image of FIG. 14(a)), and the state after 10 days was observed. The white LED light was applied from 8:00 to 18:00, and turned off from 18:00 to 8:00 the next morning. As a control plot, a dark plot without light irradiation was used.

[0125] • Experimental results: Fig. 14 shows photographic images of the light-irradiated group and the control group 10 days after the start of the experiment. In FIG. 14, (b) is a photographic image of the light irradiation section after 10 days, and (c) is a photographic image of the control section after 10 days. As shown in FIG. 14(c), in the control section (dark condition section), camellia flowers rotted and the distilled water turned yellow. On the other hand, as shown in FIG. 14(b), in the light-irradiated section in which the photocatalyst composition of Example 2 was used to irradiate white LED light, no rotting of the camellia was observed, and distilled water was used. remained transparent. From this, it was confirmed that the photocatalyst composition of Example 2 can be used to keep cut flowers fresh.

[Experimental Example 8: Effect of Preserving Freshness of Cut Flowers (Saponaria Baccaria)] [0126] An experiment was conducted to prove the effect of the photocatalyst composition of Example 2 on preserving the freshness of other different cut flowers.

Sample flower: Saponaria baccaria

•Experimental method: 50 ml of distilled water and 4 g of the beaded photocatalyst composition of Example 2 were placed in a 100 ml plant box, and cut flowers of Saponaria baccaria were arranged as test flowers. This was continuously irradiated with white LED light, and the state after 3 days was observed. The white LED light was applied from 8:00 to 18:00, and turned off from 18:00 to 8:00 the next morning. As a control section, a dark section without light irradiation was used.

[0127] •Experimental results: Fig. 15(a) shows photographic images of the white LED light irradiation area at the start of the experiment and the control area. FIG. 15(b) shows a photographic image of the white LED light irradiation section and the control section 3 days after the start of the experiment. As shown in these photographic images, the distilled water in the control section (dark condition section) 3 days after the start of the test turned white and turbid due to the proliferation of microorganisms. On the other hand, in the light irradiation section irradiated with white LED light using the photocatalyst composition of Example 2, no decomposition of the distilled water was observed even after 3 days from the start of the test, and the distilled water remained transparent. . This experimental result also confirmed that the photocatalyst composition of Example 2 can be used to maintain the freshness of cut flowers.

[Experimental Example 9: Seed sterilization effect of photocatalyst composition by ultraviolet irradiation] [0128] An experiment was conducted to verify the seed sterilization effect of the photocatalyst composition of Example 2 by ultraviolet irradiation.

Test seeds: chickpeas

Experimental method: The bead-shaped photocatalyst composition of Example 2 was placed in a 100 ml transparent container containing 50 ml of distilled water.

Add 4g and 50g of chickpeas and continuously irradiate with UV LED light using UV LED light source. The condition was observed after 7 days. The ultraviolet LED light was applied from 8:00 to 18:00 and turned off from 18:00 to 8:00 the next morning. Only distilled water was used as a control group. The set temperature during the experiment was 23°C. In addition, after the experiment, we observed the breeding state of various bacteria in chickpeas in the UV LED light irradiation area and the control area.

[0129] •Experimental results: Fig. 16(a) shows a photographic image of the control group 7 days after the start of the experiment. FIG. 16(b) shows a photographic image of the section irradiated with ultraviolet LED light 7 days after the start of the experiment. Figure 1

The arrow in 6(b) points to the bead-like photocatalyst composition of Example 2. ○ Also, FIG. , Fig. 17(b) shows a photographic image of the breeding state of various bacteria in chickpeas in the ultraviolet LED light irradiation area. The white portion in the photograph in FIG. 17 indicates the portion where bacteria are present, and the colorless portion indicates the portion where bacteria are not present.

[0130] As shown in Figs. 16(a) and 17(a), a large number of bacteria grew in the distilled water of the control group, and the water became cloudy white. On the other hand, as shown in FIGS. 16(b) and 17(b), in the ultraviolet LED light irradiation section using the photocatalyst composition of Example 2, no growth of various bacteria was observed, and even after the experiment Distilled water remained clear. From this, it was confirmed that the photocatalyst composition of Example 2 can be used for sterilizing microorganisms.

〇

(Example 5) [0131] A photocatalyst composition of Example 5 was produced using silica derived from diatom (Chaetoceros gracilis) as a silicon feedstock. The raw materials are shown in Table 7 below. The manufacturing process of the photocatalyst composition of Example 5 is the same as the manufacturing process of Example 1.

[material] [Table 7]

[0132] [Extraction process of silica from diatom] Fig. 18 shows a process of extracting silica from diatom. Diatom (Chaetoceros gracilis) was purchased from Yanmar Co., Ltd. Put 500 ml of 1 x ¹⁰⁸ ceLL/ml algae liquid in an alumina container, heat and dry at 120°C for 24 hours, and then heat at 300°C for 2 hours and then at 600°C in the air. 10 g of diatom-derived silica was obtained by sintering under the conditions of 5 hours at 300°C and 2 hours at 300°C.

[0133] (Example 6) The photocatalyst composition of Example 5 was produced using ascorbic acid as a reducing organic feedstock. The raw materials are shown in Table 8 below. Ascorbic acid and iron salt were mixed at a ratio of 1:1 (1 g of ascorbic acid + 1 g of iron salt). The manufacturing process of the photocatalyst composition of Example 6 is the same as the manufacturing process of Example 1.

[material]

[Table 8]

[0134] [Experimental Example 1: Effect of decomposing harmful substances of the photocatalyst composition by visible light irradiation] In order to verify the effect of decomposing harmful substances of the photocatalyst compositions of Examples 5 and 6 by photocatalytic reaction, visible light was used. Using a certain violet to blue light (380~495nm) LED, A decomposition experiment of methylene blue was carried out.

•Experimental method: 50 mg of the photocatalyst composition of Example 5 or 6 in powder form was added to 10 ml of methylene blue solution (5000 ppm methylene blue solution diluted 1000 times with water to 5 ppm), and LED light was emitted continuously. (10,000 lux) was irradiated for 4 hours, and the decomposition rate of methylene blue was measured. In addition, a dark condition plot without light irradiation was used as a control plot.

[0135] • Experimental results: Fig. 19 and Fig. 20 show the experimental results of each photocatalyst composition of Examples 5 and 6. Fig. 19(a) and Fig. 20(a) graphically show the experimental results of each photocatalyst composition. 19(b) and 20(b) show photographic images of the solution of each photocatalyst composition in the LED-irradiated area and the control area after the end of the experiment (4 hours after the start of the experiment).

[0136] As shown in Figures 19(a) and 20(a), methylene blue did not decompose in the dark control plot. In addition, as shown in the photographic images of Figures 19(b) and 20(b), the solution in the control group remained methylene blue (blue).

[0137] On the other hand, in the light irradiation section using each photocatalyst composition, as shown in Fig. 19(a) and Fig. 20(a), methylene blue was decomposed by continuous irradiation with violet to blue LED light. and the concentration decreased. In addition, as shown in the photographic images of FIGS. 19(b) and 20(b), in the light irradiation section using each photocatalyst composition, the color of the solution became transparent, indicating that methylene blue was decomposed. I understand.

[0138] Therefore, the photocatalyst compositions of Examples 5 and 6 exhibited a strong photocatalytic reaction against violet to blue LED light (visible light), and were found to be excellent in decomposing harmful substances such as methylene blue. rice field. The photocatalyst compositions of Examples 5 and 6 are made from algae that can be mass-produced. These algae are known to absorb a lot of carbon dioxide (C02). Therefore, in addition to this, we can expect business possibilities for various industrial applications of the functions and active ingredients of algae. A new industry using algae can be expected. Algae are expected to contribute to achieving carbon neutrality through photosynthesis and to SDGs r GOAL 13: Take concrete action against climate change. Industrial applicability

[0139I] The photocatalyst of the present disclosure is expected to be widely used for sterilization and decomposition of organic matter in a wide range of fields such as food, medicine, public health, agriculture, and environmental purification. Cross-reference to related applications

[0140] This application is based on Japanese Patent Application No. 2021 filed with the Japan Patent Office on February 4, 2021.

- 016944, the entire disclosure of which is fully incorporated herein by reference.

Claims

The scope of the claims

[Claim 1] A photocatalyst composition exhibiting catalytic activity under visible light, comprising a reducing organic substance having an action of reducing trivalent iron to divalent iron, an iron feedstock, and a glass material, wherein the reduction a photocatalyst composition, wherein the organic substance contains at least one of polyphenols and ascorbic acid, and the iron feedstock contains at least one of a divalent iron compound and a trivalent iron compound.

[Claim 2] The glass material according to claim 1, wherein the glass material contains a plant body selected from gramineous plants, fern plants, and algae, and a silicon feedstock made from any of the processed products of the plant body. Photocatalyst composition.

[Claim 3] The mixing ratio of the reducing organic substance and the silicon feedstock is 5 parts by weight of the silicon feedstock in terms of the weight of silicon element per 100 parts by weight of the dry weight of the reducing organic substance. 3. The photocatalyst composition according to claim 2, wherein the amount is at least 99 parts by weight.

[Claim 4] The mixing ratio of the reducing organic matter and the iron feedstock is such that the iron feedstock is added to 100 parts by weight of the dry weight of the reducing organic matter, and the iron feedstock is 0 in terms of the weight of the iron element. 4. The photocatalyst composition according to any one of claims 1 to 3, which is 1 part by weight or more and 10 parts by weight or less.

[Claim 5] The polyphenols are either one or more compounds selected from chlorogenic acid, caffeic acid, tannic acid, and catechin, and compounds having one or more of the above compounds in the molecule. 5. The photocatalyst composition according to any one of 1 to 4.

[Claim 6] The photocatalyst composition according to any one of claims 1 to 4, wherein the feedstock of the reducing organic matter is any one of roasted coffee beans, tea leaves, fruit juice, and dry distillation of plants. thing.

[Claim 7] A deodorant containing the photocatalyst composition according to any one of claims 1 to 6, which exhibits catalytic activity under visible light.

[Claim 8] A method for producing a photocatalyst composition exhibiting catalytic activity under visible light according to any one of claims 1 to 6, wherein the photocatalyst composition has an action of reducing trivalent iron to divalent iron A method for producing a photocatalyst composition, comprising the step of heat-treating a reducing organic substance, the iron feedstock, and the glass material in a reducing atmosphere at a heating temperature of 900° C. or higher for a heating time of 12 minutes or longer.

[Claim 9] The heating temperature is 1200 ° C or more and 1300 ° C or less, and the heating time is 12 minutes or more and 12 hours or less. A method for producing a photocatalyst composition.