JP2017047135A - Environment cleaning agent, environment cleaning method, and production method for environment cleaning agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an environment cleaning agent which can efficiently perform adsorption and decomposition of and does not easily become saturated with environmental load substances such as dioxin and the like, and which can continually perform environment cleaning.SOLUTION: Provided is an environment cleaning agent comprising titanium dioxide supported on nanofibers such as cellulose nanofibers, chitin-chitosan nanofibers, and the like. The nanofibers are chitin nanofibers or chitin-chitosan nanofibers fibrillated and opened by a high-pressure injection treatment. The titanium dioxide is one having a hydroxyapatite film thereon. The environment cleaning agent is produced by mixing a dispersion fluid of the nanofibers with titanium dioxide coated with a hydroxyapatite film, followed by drying.SELECTED DRAWING: None

Description

The present invention relates to an environmental purification agent, an environmental purification method, and a production method of an environmental purification agent, in which nanofibers, particularly chitin nanofibers or chitosan nanofibers are impregnated with titanium dioxide.

Conventionally, in order to reduce the environmental burden and reduce health damage, there are many efforts to regulate various harmful substances. Although formaldehyde, acetaldehyde, and dioxin are typical, in recent years, correspondence with 1.4 dioxane, acrylamide, methyl mercaptan, and the like has also become a problem.

For example, formaldehyde and the like are highly reactive, and are used in manufacturing and processing of industrial products using polymer materials, compressed wood products, and household consumer products such as wallpaper and paint. Formaldehyde is highly harmful to the human body, and it not only stimulates the mucous membranes of the eyes and nose but also the mucous membrane of the respiratory system, and there are an increasing number of cases where toxic effects are reported. Therefore, the relevance as a causative substance of sick house syndrome is suspected.

On the other hand, chitin / chitosan is conventionally known as a substance that adsorbs and antibacts environmentally hazardous substances such as formaldehyde and malodorous components. For example, a textile product, a film that absorbs and removes unpleasant odors generated in a room, etc., and a secondary product such as clothing, bedding, curtains, indoor interior products, etc. are disclosed (Patent Document 1). .
In addition, a coating composition containing a crushed material of a chitosan film, which is a natural polymer, as a multicolor pattern forming material is disclosed (Patent Document 2).

  In addition, titanium dioxide exhibits an action of decomposing organic matter, sulfur dioxide, nitrogen dioxide, etc. by irradiating ultraviolet rays (UV), so-called photocatalytic action, and has been used for removing contaminants. For example, a nanofiber sheet having a photocatalytic function in which titanium oxide fine particles are laminated and coated on the surface of a polymer nanofiber and a method for producing the same are disclosed (Patent Document 3).

The applicant of the present application prepares nanofibers having an average fiber diameter of about 20 nm containing chitin / chitosan or a complex thereof using only water without using any acid, alkali, organic solvent or the like. The technology has already been disclosed (Patent Document 4). Moreover, the carboxymethylcellulose nanofiber etc. which made the carboxymethylcellulose which is a biomass raw material efficiently nanofiber using water as a medium, without using an acid have already been disclosed (patent document 5).

JP 2001-329433 A Japanese Patent No. 4178309 JP 2005-264386 A JP 2011-167237 A Japanese Patent Laid-Open No. 2015-977

Conventionally, however, chitin / chitosan is generally molded by a weak acid, and the film or sheet melt-molded with a weak acid has problems such as poor water resistance and weak film strength. . In addition, there is a method in which a special amide solvent is used for dissolution and molding, but the amide solvent is toxic and such a method is not preferable from the viewpoint of environmental protection.

  Chitosan and the like can adsorb and retain environmentally hazardous substances, but cannot decompose them. For this reason, when the adsorption becomes saturated, it becomes impossible to adsorb the environmentally hazardous substance, and there is a problem that the continuously generated environmentally hazardous substance has to be appropriately replaced with a new film or porous body. . Further, when chitosan or the like is used as a coating agent, for the same reason, it is necessary to take measures such as recoating as appropriate, and there is a problem that it is difficult to reuse.

Further, when only titanium dioxide is laminated, there is room for improvement in terms of the degree of bonding, although it is in a bonded state rather than being fixed to the substrate surface. Decomposition by titanium dioxide is due to catalytic action, so it is necessary for the reactant and titanium dioxide to come into contact with each other. However, since titanium dioxide alone does not have adsorption capacity, the time until it comes into contact with the reactant becomes the rate-determining reaction time. It was. Furthermore, when titanium dioxide decomposes, there is a problem that chitosan or the like serving as a base material is damaged.

On the other hand, formaldehyde and the like are volatile, and must be efficiently adsorbed and decomposed when purifying formaldehyde and the like. It is also desirable to be able to apply not only to purification in the gas phase but also to purification in the liquid phase or solid phase. And it is desirable that it is excellent in environmental compatibility and can maintain a sustainable effect.

Accordingly, an object of the present invention is to provide an environmental purification agent, an environment that can efficiently adsorb and decompose environmentally hazardous substances, and that can be continuously purified without being saturated. It is providing the purification method and the manufacturing method of an environmental purification agent.

By using nanofibers such as chitin nanofibers or chitosan nanofibers, the inventors of the present application can adsorb and antibacterial environmentally harmful substances such as formaldehyde and malodorous components. It cannot be said that by containing titanium dioxide, it is possible to purify environmentally hazardous substances such as formaldehyde continuously as well as adsorption, and to be environmentally friendly and environmentally friendly. The present invention was completed with attention.

As a means for solving the above-mentioned problems, the environmental purification agent of the present invention is an environmental purification agent that decomposes environmentally hazardous substances such as formaldehyde, acetaldehyde, dioxin, etc. The fiber is characterized by containing titanium dioxide.

In the environmental purification method of the present invention, environmental load substances are formaldehyde, acetaldehyde, dioxin, nitric acid, ammonium nitrite, ammonia, 1.4 dioxane, acrylamide, toluene, xylene, hydrogen sulfide, trimethylamine, methyl. It includes at least one of mercaptans, and is characterized in that adsorption and decomposition are simultaneously performed using the environmental purification agent of the present invention while increasing environmental load substances.
ADVANTAGE OF THE INVENTION According to this invention, it can adsorb | suck and decompose | disassemble with respect to an environmental load substance efficiently, it becomes difficult to become a saturated state, and it becomes possible to perform a continuous environmental purification.

When the photocatalyst is exposed to light from the sun, a fluorescent lamp, or the like, a strong oxidizing power is generated on the surface, and harmful substances such as organic compounds and bacteria that come into contact with the photocatalyst can be removed. It is known that the photocatalyst has the following functions. Removal of harmful substances such as NOx, SOx and formaldehyde in the air (air purification), decomposition of odors such as acetaldehyde, ammonia and hydrogen sulfide (deodorization), and volatile organic substances such as tetrachloroethylene and trichlorethylene which are pollutants dissolved in water These include decomposition and removal of chlorine compounds (purified water), clean environment with antibacterial action (antibacterial), and prevention of dirt on window glass and outer walls (antifouling). For this reason, it can be said that it is an excellent environmental purification material. Moreover, it can mix with various purification agents which have these functions, for example, can improve a geological improvement agent, a soil improvement agent, a water quality purification agent, etc., these can be used, and is applicable also to a solid phase etc.

The environmental purification method of the present invention can also be expected to purify the environment with respect to environmentally hazardous substances such as 1.4 dioxane, acrylamide, methyl mercaptan and the like.
1.4-Dioxane is a colorless and transparent liquid organic compound at normal pressure and normal temperature. The molecular formula is C ₄ H ₈ O ₂ . It has an odor that weakens the odor of diethyl ether and is used as an aprotic solvent. Structural isomers include 1.2-dioxane and 1.3-dioxane. It is a flammable liquid and is designated as a hazardous material class 4 (first petroleum) by the Fire Service Act in Japan. It is also a PRTR Law Class 1 Designated Chemical Substance. Furthermore, it is designated as a special organic solvent of the second kind of the occupational safety and health law due to the cancer risk described later. Acrylamide has a melting point of 84.5 ° C., odorless white crystals at room temperature, and is soluble in water, alcohol, and the like. Since it is unstable to heat and light and easily polymerized, hydroquinone BHT or the like is added as a stabilizer (polymerization inhibitor) to commercially available reagents and industrial chemicals. Acrylamide is designated as a deleterious substance under the Poisonous and Deleterious Substances Control Law, has neurotoxicity and hepatotoxicity, and is absorbed from the skin.

The aspect of the environmental load substance of the present invention may be any phase such as gas phase (air phase), liquid phase, solid phase and the like. A predetermined volume is sent to the apparatus and brought into physical contact with the environmental purification agent of the present invention. After a predetermined time has elapsed, the environmental purification material of the present invention is irradiated with ultraviolet rays (UV) to thereby adsorb the adsorbed environmental load substance. It can be decomposed and the environment can be continuously purified without degrading the purification function.

The method for producing an environmental purification agent of the present invention is a method for producing an environmental purification agent that decomposes environmentally hazardous substances such as formaldehyde and acetaldehyde, and generates a dispersion fluid of nanofibers such as cellulose nanofibers, chitin nanofibers, or chitosan nanofibers. And a step of containing titanium dioxide and a step of drying, characterized in that an environmental purification agent is produced.

According to the present invention, by using cellulose nanofibers, chitin nanofibers or chitosan nanofibers, it is possible to form a highly water-resistant and high-strength adsorbent film or sheet, and water without dissolving chitosan or the like. A dispersion can be obtained. In addition, titanium oxide can be supported by using a porous cellulose nanofiber, chitin nanofiber or chitosan nanofiber that has been opened and disassembled as a scaffold. That is, since it can be stably supported on a film-like or sheet-like surface, the environment can be easily and widely purified.

According to the present invention, by using cellulose nanofiber, chitin nanofiber or chitosan nanofiber, it is possible to form a film or sheet of adsorbent with high water resistance and high strength, and to dissolve chitosan. An aqueous dispersion can be obtained. As a result, harmful substances can be adsorbed and retained in the film.

Titanium dioxide has a function of decomposing environmentally hazardous substances such as formaldehyde and acetaldehyde, and can effectively decompose environmentally hazardous substances adsorbed by a film or sheet of chitin nanofiber or chitosan nanofiber.
According to the present invention, it is possible to efficiently adsorb and decompose environmentally hazardous substances, and to continuously perform environmental purification that continuously generates these reactions even in an adsorption saturated state. Can do.

It is an external view of the high-pressure injection device used for the present invention. It is a figure which shows the film-form chitosan nanofiber used for this invention. It is a SEM image of the composite of chitosan nanofiber and hydroxyapatite-coated titanium dioxide in the present invention. It is a figure which shows the adsorption decomposition result of the Remazol brilliant blue R (RBBR) in the liquid phase in experiment of this invention. It is a flowchart which shows the manufacturing method of the environmental protection agent of this invention.

The form for implementing this invention is demonstrated below.

  The present invention is an environmental purification agent in which nanofibers 1 are impregnated with titanium dioxide 2 for decomposing environmental load substances.

The nanofiber 1 is, for example, chitin nanofiber or chitosan nanofiber, and the average diameter (short diameter) of the nanofiber 1 is about 4 to 100 nm, preferably about 4 to 50 nm, more preferably about 4 to 40 nm, Preferably it is about 4-25 nm, Most preferably, it is about 20 nm. The nanofiber 1 can be manufactured by putting the dispersion fluid 3 of chitin / chitosan into a high-pressure injection device 4 using a water jet developed by Sugino Machine Co., Ltd. and injecting the high-pressure from a high-pressure nozzle 5. When a high-pressure spraying process of 100 to 245 MPa is performed using the high-pressure spraying device 4, a similar paste (gel-like) can be obtained with cellulose. The nanofiber 1 thus obtained can be processed into a transparent or translucent film. As a suitable practical machine of the high-pressure jet processing apparatus 4, for example, “Starburst (registered trademark)” manufactured by Sugino Machine Co., Ltd. may be mentioned.

Specifically, a crystalline or sparingly water-soluble natural polymer such as chitin / chitosan can be used as the water dispersion fluid 3 to form chitin nanofibers or chitosan nanofibers by high-pressure jetting treatment. “Dispersion fluid” is a dispersion of chitin / chitosan in water. When the concentration is low, it becomes a fluid dispersion, but the viscosity increases especially as chitin / chitosan becomes finer. When the concentration is high, the properties are close to paste. The concentration of the dispersion fluid 3 of chitin nanofibers or chitosan nanofibers is preferably higher because the treatment efficiency increases. The concentration in the dispersion fluid 3 may be, for example, about 1 to 20% by weight, preferably about 1 to 15% by weight, and more preferably about 1 to 10% by weight.

The raw material of chitin / chitosan may be in any form such as fibrous or granular. Chitin can be used as a raw material directly from shells of shellfish such as shrimps and crabs. As chitin / chitosan, it is preferable to use purified chitin / chitosan which has been subjected to deproteinization / decalcification treatment by a generally known method as a raw material. Chitin / chitosan may be a commercially available raw material.

Chitosan is an environmentally friendly polymer known as marine biomass because it can be obtained by deacetylating chitin from crustacean shells such as crabs and shrimps. It has a structure in which one of the hydroxyl groups of cellulose is an amino group, and has biocompatibility and germination growth promotion. Therefore, it is also applied to soil improvement materials and can be expected to be a nutrient source for microorganisms. It also has the function of adsorbing harmful substances and can adsorb formaldehyde, which is the subject of this research.

When the raw material is subjected to high-pressure injection processing with the high-pressure injection device 4, the chitosan and the like are entangled and thinned (defibrated) while maintaining the fiber length. The “nanofiber” means a fiber whose diameter (width) is nanosized. The diameter (width) of the nanofiber 1 can be measured by an electron micrograph. Such a fiber is described as a nanofiber because the length is not nano-sized but the diameter (width) is nano-sized.

The average diameter (fiber diameter) of the nanofiber 1 is about 4 to 100 nm, preferably about 4 to 40 nm, and most preferably about 4 to 25 nm. Since the nanofiber 1 has a large fiber length / fiber width (aspect ratio), the nanofiber 1 can be formed into a film or sheet in which the nanofiber 1 is entangled while maintaining strength.

The nanofiber 1 can be expected to have an effect of increasing strength by thinning the fiber diameter (fiber width) so that the fibers are entangled with each other at high density.

The nanofiber 1 has a fiber diameter of 100 nm or less, more preferably 80 nm or less, still more preferably 60 nm or less, particularly 40 nm or less. Since the fiber diameter is very thin, it has an appearance close to a translucent solution when dispersed in water. The nanofiber 1 is not observed by the naked eye in the water, and is translucent. A liquid can also be obtained.

The dispersion fluid 3 of chitin / chitosan can be jetted at a high pressure from a high-pressure nozzle 5 using a high-pressure jetting device 4 (FIG. 1). Note that the pressure of the high pressure injection is about 30 to 245 MPa. The injection speed is about 242 to 700 m / s.

  Specifically, as a method for producing nanofibers using the high-pressure injection device 4, a high-pressure liquid in which chitin / chitosan dispersion is pressurized to 100 to 245 MPa and injected from the orifice nozzle 12 to collide with the collision hard body 15 is used. The injection process is carried out at least once, preferably by carrying out a plurality of times. The dispersion liquid of chitin / chitosan collided with the collision-use hard body 15 in the first high-pressure injection process is collected from the collection channel 16. When the high-pressure injection process is performed twice or more, the operation of pressurizing the recovered chitin / chitosan dispersion again and high-pressure injection from the orifice nozzle 12 toward the collision hard body 15 is repeated as many times as necessary to reduce the fiber diameter. (FIG. 5). According to the present embodiment, the chitin / chitosan is collided with the collision-use hard body 15 so that the fibers are entangled, the fiber diameter is reduced, and the nano-size is refined. Examples of the collision hard body 15 include a ball shape and a flat plate shape.

The dispersion fluid 3 of chitin / chitosan collided with the collision hard body 15 by high-pressure injection is recovered, and is again high-pressure injected from the high-pressure nozzle 5 toward the collision hard body 15, and this operation is performed a necessary number of times, for example, Repeat about 1 to 50 times, preferably about 1 to 40 times, more preferably about 1 to 30 times, still more preferably about 1 to 20 times, and particularly preferably about 1 to 10 times. When chitin / chitosan collides with the collision-use hard body 15, the fibers are untangled, the fiber diameter is reduced, and the nano-size is refined. In addition, as the hard body 15 for collision, shapes, such as ball shape and flat plate shape, are mentioned. The diameter of the high-pressure nozzle 5 that injects the dispersion fluid 3 at a high pressure includes about 0.1 to 0.8 mm, and is a paste, gel, slurry, film, sheet, porous body, dispersion, suspension, or emulsion. Production in form is also possible.

Commercially available titanium dioxide 2 can be used. For example, as titanium dioxide 2, in the present invention, hydroxyapatite-coated titanium dioxide (Hap-TiO ₂ ) 2 was used and various verifications were performed. Apatite is a kind of mineral name of the calcium phosphate compound. Hydroxyapatite is apatite with A = Ca, M = P, and X = OH. Titanium dioxide is a safe and harmless photocatalyst that exists as an abundant element on the earth. A photocatalyst is a substance that absorbs light and becomes in a high energy state, and gives that energy to a reactant to cause a chemical reaction. A typical photocatalyst is a semiconductor. When a semiconductor absorbs light having a band gap energy or higher, electrons in the valence band are excited to the conduction band, and holes are formed in the valence band. These electrons and holes react. Holes react with water and dissolved oxygen to generate OH radicals and the like, which decompose harmful substances. OH radicals have stronger oxidizing power than chlorine and ozone mainly used for disinfection and sterilization.
The titanium dioxide used in this experiment is of anatase type, has a band gap energy of 3.2 eV, and corresponds to light having a wavelength of about 380 nm or less. The eV conversion to the wavelength (nm) can be performed by a very simple calculation of 1240 ÷ Eg (band gap energy).

(Environmental purification agent manufacturing method and environmental purification method)
The present invention includes a step S1 for producing a dispersion fluid 3 of nanofibers 1, a step S2 containing titanium dioxide 2, and then a drying step Sa (FIG. 6 (a)). In addition, the present invention may include a step S2 of drying after the step S1 of generating the dispersion fluid 3 of the nanofiber 1. Moreover, you may provide step S3 which irradiates an ultraviolet-ray (UV) after step Sa to dry (FIG.6 (b)). Step S3 of irradiating ultraviolet rays (UV) after manufacturing the environmental purification agent may be performed after a predetermined time.
Then, chitin / chitosan is used as the dispersion fluid 3, and the dispersion fluid 3 is subjected to a high-pressure injection treatment so that the diameter of the fiber is nanosized, and then the titanium dioxide 2 is mixed. 1. Use as liquid or 2. 2. Make a sheet or 3. Make it porous or It is possible to select whether to make a powder. 2. When it is made into a sheet, it is naturally dried, and the above 3. When it is made porous, it is freeze-dried.

  In step S <b> 1 for generating the dispersion fluid 3 of the nanofiber 1, the nanofiber 1 generated by using the high-pressure injection device 4 is diluted as the dispersion fluid 3. Since the nanofiber 1 has a three-dimensional structure, it is a structure in which an environmentally hazardous substance is easily adsorbed inside. In terms of convenience and recycling, the environmental purification agent is preferably not a water dispersion but a film shape or a sheet shape in order to adsorb environmental load substances in as wide a range as possible. FIG. 2 shows a film or sheet 11 of chitosan nanofibers used in the present invention.

  In step S2 containing titanium dioxide 2, titanium dioxide 2 is mixed with the dispersion fluid 3 of nanofiber 1 obtained in step S1. The internal structure of the porous body of the nanofiber 1 has a large number of internal spaces (porous), and the titanium dioxide 2 is contained in the internal space, so that the nanofiber 1 coexists with the titanium dioxide 2. Can do. FIG. 3 is an SEM image of a composite of chitosan nanofibers and hydroxyapatite-coated titanium dioxide 2 in the present invention.

  In the drying step Sa, the nanofibers 1 containing the titanium dioxide 2 are freeze-dried to remove excess moisture in the tissue. By removing excess moisture, the bonding degree between the nanofiber 1 and the titanium dioxide 2 can be increased. Freeze-drying is a preferable drying method for maintaining a porous state.

  By placing the nanofiber 1 containing the titanium dioxide 2 thus produced in the presence of an environmental load substance, the environmental load substance is adsorbed by the adsorption ability of the nanofiber 1.

  Thereafter, by irradiating with ultraviolet rays (UV) (step S3), the environmental load substance adsorbed on the three-dimensional structure of the nanofiber 1 is decomposed by the titanium dioxide 2.

  In order to verify the effect of the nanofiber 1 containing the produced titanium dioxide 2, an experiment was conducted on how RBBR in the gas phase and liquid phase is adsorbed and decomposed. FIG. 4 shows the verification result. Note that RBBR is a kind of synthetic pigment and is a substance having a shape similar to that of dioxins. In this experiment, it was used as a dioxin pseudo-material.

(Experiment)
As an experimental method, a hydroxyapatite-coated titanium dioxide composite chitosan nanofiber film 11 was put in an RBBR solution and irradiated with ultraviolet rays (UV) (Example 1), and a hydroxyapatite-coated titanium dioxide composite chitosan nanofiber. The case where the film 11 was put and ultraviolet rays (UV) were not irradiated (Example 2) and the case where the chitosan nanofiber film 11 did not contain titanium dioxide 2 (Example 3) were compared for about 3 days.

Synthesis Hap-TiO ₂ of Hap-TiO ₂ was synthesized by the wet process. 300 ml of pH 7 phosphate buffer was prepared from 61 ml of 0.2 M disodium hydrogen phosphate, 39 ml of 0.2 M sodium dihydrogen phosphate, and 200 ml of RO water. Next, a 0.1M diammonium hydrogen phosphate aqueous solution and a 0.1M calcium nitrate aqueous solution were prepared. Thereafter, diammonium hydrogen phosphate and titanium dioxide (anatase type) were added to the buffer solution. The buffer solution was heated and stirred in an 80 ° C. water bath, and 0.1M calcium nitrate was added little by little while stirring. Thereafter, the precipitate was separated and washed while being centrifuged, and dried in a constant temperature bath at 100 ° C. to obtain Hap—TiO ₂ powder.

The Hap-TiO ₂ obtained by the composite the way to Hap-TiO ₂ of chitosan, were mixed so that 1 wt% relative to 10 wt% of chitosan suspension by freeze drying for 24 hours, Hap -TiO ₂ to obtain a composite chitosan.

Hap-TiO ₂ with Hap-TiO ₂ composite chitosan obtained by adsorption and decomposition Evaluation of methods for composite chitosan was carried out adsorption and degradation evaluation of RBBR solution. 1.0 × 10 −3 ^M RBBR was prepared, and 0.3 g of Hap-complexed chitosan prepared for comparison with Hap-TiO ₂ composited chitosan was weighed. 20 ml of RBBR solution was dispensed, and each sample was put in each. Thereafter, the samples were adsorbed while being irradiated with 350 nm ultraviolet rays (UV-A). At this time, a sample not irradiated with ultraviolet (UV) was prepared for comparison (Example 2).

When comparing Example 1 and Example 2, the SEM photograph of chitosan did not show any particular substance attached to the surface or the like, but the SEM photograph of chitosan combined with Hap-TiO ₂ Adhesion of Hap-TiO ₂ powder was observed on the front and back surfaces and inside the fine holes. This confirmed that Hap-TiO ₂ was complexed with chitosan.

Results of Adsorption / Decomposition of Hap-TiO ₂ Composite Chitosan FIG. 4 is a graph showing the relationship between the immersion time and the RBBR adsorption / decomposition rate. The broken line in the graph means the time when the RBBR solution is added.

From FIG. 4, chitosan not complexed with TiO ₂ and chitosan not irradiated with ultraviolet light (UV) are saturated after the second addition of the RBBR solution, and no change is observed. On the other hand, adsorption of Hap-TiO ₂ composite chitosan irradiated with ultraviolet rays (UV) continues even after the second addition of the solution, and RBBR is continuously adsorbed even if additional RBBR solution is added thereafter. It was done. For this reason, it was confirmed that the Hap-TiO ₂ composite chitosan was simultaneously adsorbed and decomposed by applying ultraviolet rays (UV). In addition, as a mechanism of adsorption / decomposition, it is considered that the titanium dioxide 2 was efficiently decomposed by chitosan and apatite adsorbing and collecting RBBR near the titanium dioxide 2.

It can be seen that the sample irradiated with ultraviolet rays (UV) has higher adsorption and resolution with respect to environmental load substances than the sample not irradiated with ultraviolet rays (UV). Further, in the case of Examples 2 and 3, the adsorption / resolution is saturated and does not progress after about 50 hours. On the other hand, the sample irradiated with ultraviolet rays (UV) does not have the RBBR even when the RBBR solution is added. It was confirmed that the adsorption and decomposition proceeded (Fig. 4). That is, the environmental purification agent of the example is irradiated with ultraviolet rays (UV) (reference numeral S3 in FIG. 4), and in the case of Example 1, the adsorption / decomposition is continued and the amount of the RBBR solution is continuously reduced. did. It is thought that adsorption and decomposition are performed efficiently at the same time.

In the present embodiment, the environmental purification method in the gas phase has been described as an example. However, environmental purification in the liquid phase, for example, a natural inorganic-based safe and safe water purification agent (flocculating agent that does not impose a burden on the environment). ) And environmental purification materials in the solid phase (for example, geological improvers, soil improvers).

1 Nanofiber (chitosan nanofiber),
2 Titanium dioxide,
3 Dispersed fluid,
4 High-pressure injection device,
5 High pressure nozzle,
11 Film of chitosan nanofiber used in the present invention 15 Hard body for impact.

Claims (9)

An environmental purification agent for decomposing environmentally hazardous substances such as formaldehyde, acetaldehyde, dioxin, etc., wherein titanium dioxide is contained in nanofibers such as cellulose nanofibers, chitin nanofibers or chitosan nanofibers.   The environmental purification agent according to claim 1, wherein the nanofiber is chitin nanofiber or chitosan nanofiber defibrated by a high-pressure jet treatment.   The chitin nanofibers or chitosan nanofibers defibrated by the high-pressure spraying process are processed into a film or sheet, and the titanium dioxide is supported on the front and back surfaces and the porous body. The environmental purification agent described.   2. The environmental purification agent according to claim 1, wherein the titanium dioxide is hydroxyapatite-coated titanium dioxide.   The environmentally hazardous substance is at least one of formaldehyde, acetaldehyde, dioxin, nitric acid, ammonium nitrite, ammonia, 1.4 dioxane, acrylamide, toluene, xylene, hydrogen sulfide, trimethylamine, and methyl mercaptan. And using the environmental purification agent according to any one of claims 1 to 4 of the present invention, adsorbing environmental load substances with the nanofibers, and decomposing environmental load substances with the titanium dioxide. A characteristic environmental purification method.   The environmental load substance is arranged in a predetermined gas phase, in a predetermined liquid phase, or in a predetermined solid phase, and the environmental load substance is increased while increasing the environmental load substance. 6. The environmental purification method according to claim 5, wherein adsorption and decomposition are simultaneously performed using the environmental purification agent according to any one of claims 1 to 4.   In a method for producing an environmental purification agent that decomposes environmental load substances such as formaldehyde and acetaldehyde, a step of generating a dispersion fluid of nanofibers such as cellulose nanofiber, chitin nanofiber, or chitosan nanofiber, and a step of containing titanium dioxide And a step of drying, and manufacturing an environmental purification agent that decomposes environmentally hazardous substances. The said nanofiber is chitin nanofiber or chitosan nanofiber defibrated by a high-pressure jet treatment, and said titanium dioxide is hydroxyapatite-coated titanium dioxide. Method. The method for producing an environmental purification agent according to claim 7, wherein the drying step is freeze-drying.