WO2022202149A1

WO2022202149A1 - Agent for adsorbing malodorous gas, method for producing same, and deodorizing product

Info

Publication number: WO2022202149A1
Application number: PCT/JP2022/008639
Authority: WO
Inventors: 早川真由花井; 喜直山田
Original assignee: 東亞合成株式会社
Priority date: 2021-03-24
Filing date: 2022-03-01
Publication date: 2022-09-29
Also published as: TW202243734A; KR20230159838A

Abstract

The present invention provides: an agent for adsorbing malodorous gas comprising a porous organic metal complex that includes a metal and a ligand which includes a nitrogen atom; and an application thereof.

Description

Malodorous gas adsorbent, method for producing the same, and deodorizing product

The present disclosure relates to a malodorous gas adsorbent, a method for producing the same, and a deodorant product.

Conventionally, gas adsorbents using various materials, including activated carbon and zeolite, have been developed.

For example, JP-A-2019-088499 discloses that a porous metal complex having 1,3,5-benzenetricarboxylic acid or an ester thereof as a ligand is used as a deodorant for daily life odors. there is Japanese Patent Application Laid-Open No. 2011-126775 discloses a hybrid porous material that is chemically bonded to each other and includes at least two kinds of porous material portions of different material types.

In some cases, gas adsorbents are required to adsorb malodorous gases (eg, acid gases).

In view of the above circumstances, one embodiment of the present invention provides a malodorous gas adsorbent and a deodorizing product that have a higher ability to adsorb malodorous gases than conventional ones.

<1> A malodorous gas adsorbent containing a porous organometallic complex containing a metal and a ligand containing a nitrogen atom.
<2> The malodorous gas adsorbent according to <1>, wherein the metal is at least one selected from the group consisting of Zn, Zr, Ti, Al, and Co.
<3> The malodorous gas adsorbent according to <1> or <2>, wherein the ligand containing a nitrogen atom has an aromatic ring or a heterocyclic ring.
<4> The malodorous gas adsorbent according to any one of <1> to <3>, wherein the metal is Zn and the ligand is an imidazole compound.
<5> The malodorous gas adsorbent according to any one of <1> to <4>, which is used for adsorbing acidic gases.
<6> The malodorous gas adsorbent according to any one of <1> to <5>, wherein the porous organometallic complex is a particle having a primary particle size of 0.05 μm to 3.0 μm.
<7> The malodorous gas adsorbent according to any one of <1> to <6>, which has a gas adsorption capacity of 50 mL/g or more.
<8>
The malodorous gas adsorbent according to any one of <1> to <7>, further comprising a porous material.
<9> The malodorous gas adsorbent according to <8>, wherein the porous organometallic complex is supported on a porous material.
<10> The malodorous gas adsorbent according to <8> or <9>, wherein the porous material includes at least one selected from the group consisting of porous metal oxides, zeolite, and activated carbon.
<11> 20 mg of malodorous gas adsorbent does not deliquesce in 3 liters of acetic acid gas with a concentration of 600 ppm prepared in air with a humidity of 40% in an environment of 25 ° C. for 24 hours, <8> to <10> The malodorous gas adsorbent according to any one of .
<12> 40 mg of the malodorous gas adsorbent was exposed to 300 mL of acetic acid gas with a concentration of 15,000 ppm prepared in air with a humidity of 40% in an environment of 40°C for 24 hours. The malodorous gas adsorbent according to any one of <8> to <11>, wherein the increase per unit is 0.35 g or less.
<13> A deodorant product containing the malodorous gas adsorbent according to any one of <1> to <12>.
<14> A step of mixing a solution containing a metal salt with a solution containing a porous material and a ligand containing a nitrogen atom; and a method for producing a malodorous gas adsorbent.

According to one embodiment of the present invention, it is possible to provide a malodorous gas adsorbent and a deodorizing product that have a higher ability to adsorb malodorous gases than conventional ones.

1 is an X-ray diffraction pattern of powder X-ray diffraction measurement of the porous organometallic complex obtained in Example 1. FIG. 2 is an X-ray diffraction pattern of powder X-ray diffraction measurement of the porous organometallic complex obtained in Example 2. FIG. 3 is a SEM photograph of the malodorous gas adsorbent obtained in Example 3. FIG. 4 is a SEM photograph of the malodorous gas adsorbent obtained in Example 4. FIG. 5 is a SEM photograph of the malodorous gas adsorbent obtained in Example 5. FIG. 6 is a SEM photograph of the malodorous gas adsorbent obtained in Example 6. FIG.

The gas adsorbent of the present disclosure, the method for producing the same, and the deodorant product will be described in detail below.
In this specification, the numerical range indicated using "to" means a range including the numerical values before and after "to" as the minimum and maximum values, respectively.
In the numerical ranges described stepwise in this specification, the upper limit or lower limit described in a certain numerical range may be replaced with the upper limit or lower limit of another numerical range described stepwise. Moreover, in the numerical ranges described in this specification, the upper limit or lower limit described in a certain numerical range may be replaced with the values shown in the examples.
As used herein, the amount of each component in the composition refers to the total amount of the multiple substances present in the composition when there are multiple substances corresponding to each component in the composition, unless otherwise specified. means
Moreover, in the present specification, a combination of two or more preferred aspects is a more preferred aspect.
Moreover, in this specification, the term "deliquescence resistance" refers to the property of not deliquescing or hardly deliquescing. “Deliquescence” refers to a phenomenon in which, for example, when a malodorous gas adsorbent is exposed to a malodorous gas, it absorbs components of the malodorous gas and changes its shape.

<Foul-smelling gas adsorbent>
A malodorous gas adsorbent that is one embodiment of the present invention contains a porous organometallic complex containing a metal and a ligand containing a nitrogen atom. In the malodorous gas adsorbent, which is one embodiment of the present invention, the ligands contained in the porous organometallic complex contain nitrogen atoms, so components in the gas react with the nitrogen atoms and chemisorb. Also, components in the gas are physically adsorbed into the pores of the porous metal complex. The malodorous gas adsorbent, which is one embodiment of the present invention, has a large specific surface area and has a higher adsorption capacity for malodorous gases than conventional ones due to the effects of both chemisorption and physical adsorption.

In the present disclosure, "malodorous gas" refers to gas that makes people feel uncomfortable. A gas that people feel uncomfortable generally refers to a gas that is evaluated on the negative side in the 9-level pleasure/discomfort display method in the gas sensory test.

(Porous organometallic complex)
A porous organometallic complex contains a metal and a ligand containing a nitrogen atom. "Porous" refers to a structure having a plurality of pores, and the plurality of pores may or may not communicate with each other.

-metal-
The number of metals contained in the porous organometallic complex may be one, or two or more.

The metal contained in the porous organometallic complex is not particularly limited, and examples include Mg, Ca, Sr, Ba, Sc, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re , Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Hg, Al, Ga, In, Tl, Si, Ge, Sn, Pb, As, Sb , and Bi. Among them, from the viewpoint of improving gas adsorption capacity, the metal is preferably at least one selected from the group consisting of Zn, Zr, Ti, Al, and Co, and more preferably Zn.

-ligand-
The number of ligands contained in the porous organometallic complex may be one, or two or more. When two or more ligands are contained in the porous organometallic complex, at least one ligand containing a nitrogen atom may be contained, and a ligand containing no nitrogen atom may be contained. good too.

Examples of ligands containing nitrogen atoms include amine compounds and nitrogen-containing heterocyclic compounds.

Amine compounds include, for example, monoamines, diamines, and triamines. The amine compound may be any of primary amine, secondary amine, tertiary amine and quaternary ammonium.

Examples of amine compounds include aromatic amines such as aniline, 1,2-diaminobenzene, 1,3-diaminobenzene, 1,4-diaminobenzene, 1,3,5-triaminobenzene, and 2-aminoterephthalic acid. is mentioned.

Nitrogen-containing heterocyclic compounds include pyridine, pyrrolidine, pyrroline, piperidine, pyrimidine, indole, azaindole, carbazole, indazole, norharman, harman, imidazole, oxazole, thiazole, pyrazole, pyrrole, benzimidazole, benzotriazole, benzoxazole, benzothiazole, benzothiadiazole, isoxazole, isothiazole, oxadiazole, thiadiazole, triazine, benzisoxazole, pyrazine, quinoline, benzoquinoline, acridine, thiazoline, quinuclidine, imidazoline, oxazoline, thiazoline, and isoquinoline, and , and derivatives thereof.

Above all, the ligand preferably has an aromatic ring or a heterocyclic ring from the viewpoint of improving the ability to adsorb malodorous gases. Examples of aromatic rings include benzene ring, naphthalene ring, fluorene ring, anthracene ring, indene ring, and indane ring. Heterocyclic rings include imidazole, oxazole, thiazole, pyridine, pyrazine, pyrrole, furan, thiophene, pyrazole, isoxazole, isothiazole, pyridazine, and pyrimidine rings. Among them, the ligand preferably has a heterocyclic ring, more preferably a nitrogen-containing heterocyclic ring.

In particular, from the viewpoint of further improving the ability to adsorb malodorous gases, the ligand more preferably has a nitrogen-containing heterocycle, and is preferably an imidazole compound. Imidazole compounds include imidazole and imidazole derivatives.

Examples of imidazole compounds include imidazole, 1-methylimidazole, 2-methylimidazole, 4-methylimidazole, 2-ethylimidazole, 2-phenylimidazole, and benzimidazole.

The porous organometallic complex contained in the malodorous gas adsorbent preferably has Zn as the metal and an imidazole compound as the ligand. Also, the porous organometallic complex is preferably a zeolite-like imidazolate structure (ZIF).

One type of porous organometallic complex may be contained alone, or two or more types may be contained.
The content of the porous organometallic complex in the malodorous gas adsorbent is preferably 10% by mass or more, more preferably 50% by mass or more, relative to the total amount of the malodorous gas adsorbent. The upper limit of the content of the porous organometallic complex is not particularly limited, and is, for example, 100% by mass. That is, the malodorous gas adsorbent may consist only of the porous organometallic complex.

When the malodorous gas adsorbent contains a porous material described later, the content of the porous organometallic complex in the malodorous gas adsorbent is 10% by mass to 90% by mass with respect to the total amount of the malodorous gas adsorbent. preferably 20% by mass to 80% by mass, even more preferably 30% by mass to 70% by mass.

-Physical properties-
The porous organometallic complex preferably has a maximum pore size of 0.2 nm to 2.0 nm, more preferably 0.4 nm to 1.5 nm.

The maximum pore size means the maximum diameter of pores formed in the porous organometallic complex. The pore size means the diameter of the entrance of the pore formed in the porous organometallic complex.
The maximum pore diameter is measured using a nitrogen adsorption measuring device, for example, model number "AUTOSORB-1" (manufactured by Quantachrome Instruments).

The porous organometallic complex is preferably particles, and the primary particle size of the particles is preferably 0.05 μm to 3.0 μm, more preferably 0.1 μm to 2.0 μm, and more preferably 0.2 μm. More preferably, it is ~1.5 μm.

A primary particle size is measured by the following method.
First, the porous organometallic complex is observed at an appropriate magnification using a semi-in-lens scanning electron microscope (product name “S-4800”, manufactured by Hitachi High-Technologies Corporation). Particles are identified based on the obtained SEM image. Measure the diameter of the longest part of the particle in the SEM image at a magnification where a single particle can be observed. 100 particles are measured, and the average value is taken as the primary particle size.

(porous material)
The malodorous gas sorbent comprises a porous material. The "porous" of a porous material refers to a structure having a plurality of pores.

Examples of porous materials include porous metal oxides, zeolites, activated carbon, porous polymers, porous resins, porous fibers, and porous natural products. Among them, from the viewpoint of improving deliquescence resistance, at least one selected from the group consisting of porous metal oxides, zeolite, and activated carbon is preferable.

A porous metal oxide may be a compound in which the metal oxide itself has a plurality of pores, or may be one in which particles of the metal oxide aggregate (eg, aggregate) to form a porous structure. Porous metal oxides include silica, aluminum silicate, magnesium silicate, and copper silicate. Among them, the porous metal oxide is preferably silica.

The type of silica is not particularly limited, and known silica gel and porous silica can be used. The particle size of silica is not particularly limited, but the median size (D50) is preferably 0.5 μm to 20 μm, more preferably 1.0 μm to 10 μm. Particle size can be measured, for example, using a laser diffraction scattering method. Although the specific surface area of silica is not particularly limited, it is preferably 200 m ² /g to 900 m ² /g, more preferably 300 m ² /g to 800 m ² /g. The specific surface area can be determined, for example, by the BET method.

The type of zeolite is not particularly limited, and may be synthetic zeolite or natural zeolite. The particle size of the zeolite is not particularly limited, but the median size (D50) is preferably 0.5 μm to 20 μm, more preferably 1.0 μm to 10 μm. Particle size can be measured, for example, using a laser diffraction scattering method. Although the specific surface area of zeolite is not particularly limited, it is preferably 200 m ² /g to 900 m ² /g, more preferably 300 m ² /g to 800 m ² /g. The specific surface area can be determined, for example, by the BET method.

One type of porous material may be contained alone, or two or more types may be contained.
The content of the porous material in the malodorous gas adsorbent is preferably 10% by mass to 90% by mass, more preferably 20% by mass to 80% by mass, relative to the total amount of the malodorous gas adsorbent. , 30% by mass to 70% by mass.

The malodorous gas adsorbent may contain components other than the porous organometallic complex and the porous material. Other components are not particularly limited, and examples include known acid gas deodorants, basic gas deodorants, sulfur-based gas deodorants, aldehyde-based gas deodorants, ketone-based gas deodorants, and the like. Other deodorants; antibacterial agents, antifungal agents, antiviral processing agents, antiallergen agents, antifoaming agents, coloring agents, preservatives, viscosity modifiers, fragrances, surfactants, water, solvents, preservatives, moisturizing agents agents, thickeners, pH adjusters, bleaches, chelating agents, water-soluble salts, and oils.

(form)
The form of the malodorous gas adsorbent, which is one embodiment of the present invention, is not particularly limited as long as it contains a porous organometallic complex and a porous material. For example, the malodorous gas adsorbent may be in the form of a mixture of the porous organometallic complex and the porous material, or may be in the form of supporting the porous organometallic complex on the porous material.

From the viewpoint of further improving deliquescence resistance, the porous organometallic complex is preferably supported on a porous material. In the present disclosure, "a porous organometallic complex is supported on a porous material" means that the porous organometallic complex is held in a state of adhering to the porous material. The attached state is not particularly limited, and examples thereof include chemically and/or physically interacting states between the porous organometallic complex and the porous material. Whether or not the porous organometallic complex is supported on the porous material can be determined, for example, by observing the state in which the porous organometallic complex adheres to the porous material with a scanning electron microscope (SEM). can. Further, for example, by performing elemental mapping by X-ray microanalyzer (hereinafter referred to as “XMA”) analysis during SEM observation, the supported porous organometallic complex can be identified.

The particles of the porous organometallic complex may be stacked on the porous material in several stages, or may be attached in a single layer. Moreover, the porous organometallic complex particles may adhere only to a part of the porous material, or may adhere uniformly to the entire porous material.

It is preferable that the particles of the porous organometallic complex adhere to the porous material in a single layer, and that they adhere uniformly as a whole. The porous organometallic complex is preferably deposited onto the porous material by reacting the raw materials of the porous organometallic complex in the presence of the porous material. Although the particle size distribution of the particles of the porous organometallic complex on the porous material is not particularly limited, it is preferably narrower.

(Mass ratio of porous material to porous organometallic complex)
The mass ratio of the porous material to the porous organometallic complex is preferably porous material:porous organometallic complex=9:1 to 1:9, more preferably 8:2 to 2:8. More preferably, the ratio is from 3:7 to 7:3. The mass ratio can be obtained, for example, from the mixing ratio of the mass of the raw porous material and the mass of the porous organometallic complex. The mass ratio can be determined, for example, by dissolving a malodorous gas adsorbent containing a porous material and a porous organometallic complex in a strong acid and performing high-frequency inductively coupled plasma (hereinafter referred to as "ICP") emission spectrometry. . Furthermore, analysis means such as CHN elemental analysis and differential thermal/thermogravimetric simultaneous analysis can be used in combination.

(Particle size ratio between porous material and porous organometallic complex)
The porous material is preferably larger than the porous organometallic complex. Primary particle size of porous material: primary particle size of porous organometallic complex = preferably 1000:1 to 1:1, more preferably 500:1 to 2:1, 100:1 to 5 :1 is more preferable. The ratio of primary particle sizes can be determined, for example, from SEM images of malodorous gas adsorbents comprising porous materials and porous organometallic complexes.

<Coverage of the porous organometallic complex with respect to the porous material>
The coverage of the porous organometallic complex on the porous material is calculated based on the area covered by the porous organometallic complex in the porous material relative to the surface area of the porous material. The coverage is preferably 10% or more, more preferably 30% or more, and even more preferably 50% or more. The area covered by the porous organometallic complex in the porous material can be measured from SEM images.

(Application)
The malodorous gas adsorbent, which is one embodiment of the present invention, is preferably used for adsorbing acid gases. An acid gas is a molecular gas that has free protons and exhibits volatility. Examples of acidic gases include carboxylic acids such as formic acid, acetic acid, propionic acid, butyric acid, valeric acid and isovaleric acid; hydrogen halides such as hydrogen chloride and hydrogen bromide; inorganic acids such as carbonic acid, nitric acid and sulfuric acid; Acidic gases such as hydrogen sulfide are included. Among them, the malodorous gas adsorbent which is one embodiment of the present invention is more preferably used for adsorbing carboxylic acids such as formic acid, acetic acid, propionic acid, butyric acid, valeric acid and isovaleric acid, and hydrogen sulfide. . Moreover, it is particularly preferable that the malodorous gas adsorbent, which is one embodiment of the present invention, is used for adsorbing acetic acid gas. That is, the malodorous gas adsorbent of one embodiment of the present invention is preferably an acidic gas adsorbent, and more preferably an acetic acid gas adsorbent.

The gas adsorption capacity of the malodorous gas adsorbent is not particularly limited, but is preferably 50 mL/g or more, more preferably 100 mL/g or more, and even more preferably 150 mL/g or more. The upper limit of the gas adsorption capacity is not particularly limited. The acid gas adsorption capacity of the malodorous gas adsorbent is preferably 50 mL/g or more, more preferably 100 mL/g or more, and even more preferably 150 mL/g or more.

In the present disclosure, "adsorption capacity" means the maximum amount of a specific gas that can be adsorbed by a malodorous gas adsorbent, and means the adsorption capacity adsorbed by both physical adsorption and chemical adsorption mechanisms.

In the present disclosure, the gas adsorption capacity is measured by the following method.

(1) Place the malodorous gas adsorbent in a bag made of a vinyl alcohol polymer film, seal the bag, and fill the bag with air so that the volume becomes 3 liters.
(2) Fill the bag with the specific gas so that the concentration of the specific gas is 30 ppm.
(3) After 30 minutes, the concentration of the specific gas remaining in the bag is measured with a gas detector tube, and then 30 ppm of the specific gas is added to the bag.
(4) After another 30 minutes, the concentration of the specific gas remaining in the bag is measured with a gas detector tube.
(5) Until the concentration of the specific gas in the bag does not decrease (that is, after 30 minutes, it is confirmed that the concentration of the remaining specific gas is 30 ppm higher than the concentration of the specific gas obtained in the immediately preceding measurement. ) Repeat the above operations (2) and (3).
(6) The point at which the gas concentration stops decreasing is regarded as the limit point of the amount of specific gas that can be adsorbed by the malodorous gas adsorbent (that is, the end point of the test), and the operation of supplying the specific gas is stopped.
The acetic acid gas adsorption capacity of the malodorous gas adsorbent is calculated based on the following formula.
Gas adsorption capacity (mL/g) = [{Number of gas injections up to the test end point x 30 (ppm) - residual gas amount (ppm) at the end of the test} x 3000 (mL) x 1/1000000] / used for measurement Amount of bad smell gas adsorbent (g)

The malodorous gas adsorbent comprising a porous material, which is one embodiment of the present invention, is prepared by dissolving 20 mg of the malodorous gas adsorbent in 3 liters of acetic acid gas with a concentration of 600 ppm prepared in air with a humidity of 40% under an environment of 25 ° C. It is preferred that it does not deliquesce under the conditions of 24 hours of exposure at .

Whether or not it is deliquescent is determined using the following method.

After exposing 20 mg of the malodorous gas adsorbent to 3 liters of acetic acid gas with a concentration of 600 ppm prepared in air with a humidity of 40% in an environment of 25°C for 24 hours, the appearance of the malodorous gas adsorbent is visually confirmed. It is determined which of the following A to C corresponds, and in the case of A or B, it is determined that there is no deliquescence.
A: The appearance of the malodorous gas adsorbent after 24 hours does not deliquesce, and the solid malodorous gas adsorbent remains free-flowing.
B: After 24 hours, the appearance of the malodorous gas adsorbent did not change significantly, and the surface did not have stickiness, but a change as if the surface had absorbed moisture was observed.
C: After 24 hours, the malodorous gas adsorbent was deliquesced and had a smooth appearance, did not maintain a solid state, and had a sticky surface.

A malodorous gas adsorbent comprising a porous material, which is one embodiment of the present invention, is exposed to 40 mg of malodorous gas adsorbent in 300 mL of acetic acid gas with a concentration of 15000 ppm prepared in air with a humidity of 40% at 40 ° C. for 24 hours. It is preferable that the amount of increase per 1 g of the malodorous gas adsorbent after 24 hours is 0.35 g or less, more preferably 0.25 g or less.

Weight gain due to deliquescence is measured by the following method.
(1) A vinyl alcohol polymer film is cut into a size of 2 cm x 2 cm.
(2) Place the cut film on the aluminum cup, and spread the malodorous gas adsorbent thinly on it.
(3) Measure the total weight before and after placing the malodorous gas adsorbent.
(4) Place (2) in a vinyl alcohol polymer film bag.
(5) 100 mL of air (40% humidity) and acetic acid gas are injected with a syringe so that the concentration of acetic acid gas becomes 15000 ppm.
(6) Allow to stand for 24 hours in a constant temperature machine at 40°C.
(7) After 24 hours, take out the aluminum cup and measure the total weight. Calculate the weight change before and after the test based on the following formula.
Increased amount (g) per gram of malodorous gas adsorbent = {(Weight of malodorous gas adsorbent after 24 hours of acetic acid gas injection (g)) - (Weight of malodorous gas adsorbent before acetic acid gas injection (g))} ÷ (weight (g) of malodorous gas adsorbent before injection of acetic acid gas)

The malodorous gas adsorbent that is one embodiment of the present invention can be used for various purposes as a deodorant. The malodorous gas adsorbent, which is one embodiment of the present invention, can be blended with fibers, resins, liquids (eg, water, organic solvents, etc.) and used as raw materials for producing deodorant products.

Uses of deodorant products include, for example, deodorant processing liquids, deodorant fibers, deodorant resin compositions, deodorant fabrics and deodorant filter media.

<Deodorant products>
A deodorizing product, which is one embodiment of the present invention, contains the above malodorous gas adsorbent.
-Deodorant resin composition-
Since the malodorous gas adsorbent has a higher adsorption capacity for acidic gases than conventional ones, it can be applied to deodorant resin compositions.

A deodorant resin composition, which is one embodiment of the present invention, contains the above-mentioned malodorous gas adsorbent and resin.

The method for producing the deodorant resin composition is not particularly limited, and examples include a method of mixing the malodorous gas adsorbent and the resin and then molding it, and a method of preparing a pellet-shaped resin containing a high concentration of the malodorous gas adsorbent. A method in which a pellet-shaped resin is mixed with another resin and then molded is exemplified. Molding methods include injection molding, extrusion molding, inflation molding, and vacuum molding.

The resin constituting the deodorant resin composition is not particularly limited, and examples include polyester, polyurethane, polyolefin, polyamide, polyether, acrylic resin, acrylonitrile-butadiene-styrene (ABS resin), nylon, polystyrene, polycarbonate and vinyl chloride. resin.

The content of the malodorous gas adsorbent in the deodorant resin composition is preferably 0.1% by mass to 35% by mass, more preferably 0.2% by mass to 30% by mass, relative to the total amount of the deodorant resin composition. %, more preferably 0.5% by mass to 25% by mass.

The deodorizing resin composition contains pigments, dyes, antioxidants, light stabilizers, antistatic agents, foaming agents, impact-resistant reinforcing agents, glass fibers, moisture-proof agents, thickeners, acidic gas deodorants, basic Other known deodorants such as gas deodorants, sulfur-based gas deodorants, aldehyde-based gas deodorants, ketone-based gas deodorants; , antifoaming agents, coloring agents, preservatives, viscosity modifiers, fragrances, surfactants, preservatives, moisturizing agents, water-soluble salts, oil agents, and other additives.

The deodorant resin composition, which is one embodiment of the present invention, can be applied to various products that require deodorant properties, such as home electric appliances such as air purifiers, refrigerators, and air conditioners; , general household goods such as sponges; various nursing care products such as portable toilets, wallpaper, toilet bowls, toilet seats, kitchen counters, ventilation fan filters, paints and other residential building materials; vehicle interiors, pet products, and daily necessities.

-Deodorizing liquid-
Since the malodorous gas adsorbent has a higher adsorption capacity for acidic gases than conventional ones, it can be applied to the deodorant processing liquid.

The deodorant processing liquid contains the above-mentioned malodorous gas adsorbent, and preferably contains a dispersion medium, a dispersant, and an adhesive in addition to the malodorous gas adsorbent.

Examples of dispersion media include organic solvents such as alcohols, ketones, esters, and hydrocarbons, and water.

When the dispersion medium is water, examples of dispersants include polycarboxylic acid-based dispersants, naphthalenesulfonic acid formalin condensation-based dispersants, polyethylene glycol, alkylsulfonic acid-based dispersants, quaternary ammonium-based dispersants, Examples include higher alcohol alkylene oxide dispersants and polyphosphoric acid dispersants. Further, when the dispersion medium is an organic solvent, the dispersant includes, for example, a polycarboxylic acid alkyl ester dispersant, a polyether dispersant, a polyalkylamine dispersant, a polyhydric alcohol ester dispersant, and Alkylpolyamine-based dispersants may be mentioned.

Examples of adhesives include novolak-type or resol-type phenolic resins, alkyd resins, aminoalkyd resins, acrylic resins, vinyl chloride resins, vinylidene chloride resins, silicone resins, fluorine resins, epoxy resins, urethane resins, saturated polyester resins, and melamine resins.

The content of the malodorous gas adsorbent in the deodorant processing liquid is preferably 0.1% by mass to 50% by mass, more preferably 0.2% by mass to 30% by mass, relative to the total amount of the deodorant processing liquid. more preferably 0.3% by mass to 20% by mass.

－Deodorant fiber－
The malodorous gas adsorbent has high malodorous gas adsorption performance and a small primary particle size of 0.05 to 3.0 μm, so that it can be spun without yarn breakage. Therefore, it can be applied to deodorant fibers.

The method of producing the deodorant fiber is not particularly limited, and examples include a method of kneading the malodorous gas adsorbent into a fiber raw material and then spinning it, and a method of adding the malodorous gas adsorbent to spun fibers such as chemical fibers and natural fibers. A method of applying and drying a deodorant processing liquid containing.

Fibers constituting deodorant fibers are not particularly limited, and examples include chemical fibers such as polyester, polyurethane, nylon, rayon, acrylic, vinylon, polypropylene, and polyethylene; natural fibers such as cotton, hemp, silk, and wool; and glass. Inorganic fibers such as fibers, carbon fibers, alumina fibers, and metal fibers can be used. These fibers may be used singly or in combination of two or more.

The content of the malodorous gas adsorbent in the deodorant fiber is preferably 0.1% by mass to 5.0% by mass, more preferably 0.2% by mass to 3.0% by mass, relative to the total amount of the deodorant fiber. %, more preferably 0.5 mass % to 2.0 mass %.

The deodorizing fiber that is one embodiment of the present invention can be applied to various textile products, such as underwear, stockings, socks, masks, futons, duvet covers, floor cushions, blankets, carpets, curtains, sofas, and car seats. , air filters, air purifier filters, air conditioner filters and nursing care clothing.

-Deodorant fabric-
Since the malodorous gas adsorbent has a higher adsorption capacity for acidic gases than conventional ones, it can be applied to deodorant fabrics. The fabric may be woven, nonwoven, or a combination thereof.

The method of producing the deodorant fabric is not particularly limited, and examples include a method of weaving using the deodorant fiber, a method of producing a nonwoven fabric by a known method using the deodorant fiber, and a method of adsorbing the malodorous gas on the fabric. A method of applying a deodorant processing liquid containing an agent and drying it can be mentioned.

The content of the malodorous gas adsorbent in the deodorant fabric is preferably 0.1 to 5.0 g, more preferably 0.2 to 4.0 g, per 1 m ² of the area of the deodorant fabric. It is preferably 0.3 to 3.0 g, more preferably 0.3 to 3.0 g.

- Deodorizing filter material -
Since the malodorous gas adsorbent has a higher adsorption capacity for acidic gases than conventional ones, it can be applied to a deodorizing filter medium.

The method for producing the deodorizing filter medium is not particularly limited, and for example, a method of applying a deodorizing processing liquid containing the above-mentioned malodorous gas adsorbent to a base material and drying it, and a method of using the above-mentioned deodorizing fiber or cloth. and a method of producing a deodorizing filter medium.

The base material is not particularly limited as long as it has pores so that it can be filtered, and examples include fibers, ceramics and metals.

The content of the malodorous gas adsorbent in the deodorizing filter medium is preferably 0.1 g to 40 g, more preferably 0.5 g to 35 g, and 1.0 g per 1 m ² of substrate area. More preferably ~30g.

The deodorant filter medium, which is one embodiment of the present invention, can be applied to various products, such as air filters, air purifier filters, air conditioner filters, drainers and water purifiers.

<Method for producing malodorous gas adsorbent>
The malodorous gas adsorbent that is one embodiment of the present invention may be produced by a known method, for example, the steps of obtaining a porous organometallic complex and mixing the porous organometallic complex with a porous material. and may be manufactured by a method including: The porous organometallic complex can be produced by, for example, a step of mixing a solution containing a metal salt and a solution containing a ligand, a step of solid-liquid separation of the mixed solution obtained by mixing to obtain a solid, and a step of separating the solid. It can be produced by a method including a step of drying and, if necessary, a step of pulverizing the dried solid.

There are no particular restrictions on the solid-liquid separation method in the process of obtaining solids, for example, filtration methods such as natural filtration, suction filtration, vacuum filtration, and pressure filtration; Separation methods that do not use Among them, the solid-liquid separation method is preferably a filtration method.

Above all, the malodorous gas adsorbent that is one embodiment of the present invention is preferably produced by the following production method.

A method for producing a malodorous gas adsorbent, which is an embodiment of the present invention, comprises a step of mixing a solution containing a metal salt, a solution containing a porous material, and a ligand containing a nitrogen atom; and a step of solid-liquid separation to obtain a solid matter from the mixed liquid obtained by the above. The method for producing the malodorous gas adsorbent, which is one embodiment of the present invention, preferably further includes a step of drying the solid matter and a step of pulverizing the dried solid matter. The malodorous gas adsorbent produced by such a production method contains a porous organometallic complex containing a metal and a ligand containing a nitrogen atom, and a porous material. Also, the porous organometallic complex is obtained in a state of being supported on a porous material.

- A step of mixing a solution containing a metal salt with a solution containing a porous material and a ligand containing a nitrogen atom -
The metal salt is not particularly limited, and examples thereof include acid salts such as metal nitrates, hydrochlorides, sulfates, carbonates and acetates, and halides such as chlorides, bromides and iodides.

Metals constituting the metal salt are not particularly limited, and examples include Mg, Ca, Sr, Ba, Sc+, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe , Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Hg, Al, Ga, In, Tl, Si, Ge, Sn, Pb, As, Sb, and Bi can be mentioned. Among them, from the viewpoint of improving gas adsorption capacity, the metal is preferably at least one selected from the group consisting of Zn, Zr, Ti, Al, and Co, and more preferably Zn.

In the solution containing the metal salt, the type of solvent is not particularly limited, and examples include water and organic solvents.

A preferred embodiment of the porous material is the same as the porous material described in the section on the malodorous gas adsorbent. Moreover, preferred aspects of the ligand are the same as those described in the column of the malodorous gas adsorbent.

In the solution containing ligands containing nitrogen atoms, the type of solvent is not particularly limited, and examples include water and organic solvents.

The mixing method is not particularly limited. For example, the porous material may be added to the solution containing the metal salt, or the solution containing the metal salt may be added to the porous material. The solution containing the ligand may be added to the dispersion containing the metal salt and the porous material and stirred, or the dispersion may be added to the solution containing the ligand. Alternatively, the porous material may be added to the solution containing the ligand, or the solution containing the ligand may be added to the porous material. The solution containing the metal salt may be added to the dispersion containing the ligand and the porous material, or the dispersion may be added to the solution containing the metal salt.

Alternatively, a mixture of a solution containing a metal salt and a solution containing a ligand may be mixed with a porous material. The porous material may be mixed as it is, or may be dispersed in a solvent in advance and then mixed.

Among them, the solution containing the metal salt is mixed with the porous material and then the solution containing the ligand is added, or the solution containing the ligand and the porous material are mixed and then the solution containing the metal salt is added. is preferred.

- A step of obtaining a solid by solid-liquid separation from the mixed liquid obtained by mixing -
In the above process, when the solution containing the metal salt and the solution containing the ligand containing nitrogen atoms are mixed, a solid is produced. Specifically, in the presence of the porous material, a mixture containing the porous material and the porous organometallic complex and/or a composite in which the porous organometallic complex is supported on the porous material is solid. obtained as a product. In this step, the solid matter thus obtained is separated by solid-liquid separation.

It is preferable to wash the solid matter after the solid-liquid separation operation. A solvent used for washing is, for example, water.

-The process of drying the solid matter-
By drying the solid, a malodorous gas adsorbent, which is a composite of a porous organometallic complex supported on a porous material, is obtained.
The drying method is not particularly limited, and a commonly known method can be used. The drying temperature is, for example, 60°C to 200°C. The drying time is, for example, 0.5 hours to 24 hours.

- Step of pulverizing the dried precipitate -
The pulverization method is not particularly limited, and examples thereof include a method of pulverizing using a pulverizer such as a mortar, ball mill, jet mill, hammer mill, pin mill, and bead mill.

Hereinafter, the present disclosure will be described more specifically with reference to examples, but the present disclosure is not limited to the following examples as long as it does not exceed the gist thereof.

<Example 1>
35 mL of pure water and 10 g of 2-methylimidazole were added to a beaker and stirred at 25° C. for 10 minutes to prepare an aqueous 2-methylimidazole solution. Next, 6 mL of pure water and 0.9 g of zinc nitrate were mixed and stirred at 25° C. for 10 minutes to prepare an aqueous zinc nitrate solution. Furthermore, the 2-methylimidazole aqueous solution and the zinc nitrate aqueous solution were mixed and stirred at 25° C. for 10 minutes. The obtained reaction solution was filtered, and the filtered solid was washed with pure water. The washed solid was dried overnight at 80° C. and then pulverized in a mortar to obtain a porous organometallic complex (ZIF-8). The resulting porous organometallic complex (ZIF-8) was used as a malodorous gas adsorbent.
The obtained porous organometallic complex was identified by powder X-ray diffraction measurement, and was found to be a crystalline substance in which organic ligands were coordinated to metal ions. FIG. 1 shows the results of powder X-ray diffraction measurement. Powder X-ray diffraction measurement was performed using a powder X-ray diffractometer (product name “D8 ADVANCE”, manufactured by Bruker Japan) at a diffraction angle of 3° to 50°.

<Example 2>
40 mL of N,N-dimethylformamide (DMF), 0.62 g of 2-aminoterephthalic acid, and 0.87 g of ZrCl ₄ were added to a Teflon (registered trademark) container and dissolved by ultrasonic stirring. Next, 0.375 mL of 35% by mass concentrated hydrochloric acid was added to the Teflon container, and the Teflon container was placed in a stainless steel jacket, sealed, and heated in an oven at 120° C. for 24 hours while standing still. After 24 hours, it was allowed to cool to room temperature. After that, the contents of the Teflon container were transferred to a 50 mL centrifuge tube and separated into a precipitate and a supernatant by centrifugation. The supernatant was removed by decantation, and the precipitate was suspended in 50 mL of DMF. After centrifugation was performed again and the supernatant was removed, the remaining precipitate was suspended in 50 mL of methanol. Centrifugation was performed again and the supernatant was removed. After that, the resulting precipitate was transferred to a 100 mL beaker, suspended in 80 mL of methanol, and stirred overnight at 25°C. The suspension was subjected to suction filtration, and the filtered solid was washed with methanol. The washed solid was dried overnight at 80° C. to obtain a porous organometallic complex (UiO-66-NH ₂ ). The resulting porous organometallic complex (UiO-66-NH ₂ ) was used as a malodorous gas adsorbent.
The obtained porous organometallic complex was identified by powder X-ray diffraction measurement, and was found to be a crystalline substance in which organic ligands were coordinated to metal ions. FIG. 2 shows the powder X-ray diffraction measurement results.

<Comparative Example 1>
Benzene-1,3,5-tricarboxylic acid copper (product name “Basolite C300”, manufactured by BASF) was used as a malodorous gas adsorbent.

<Comparative Example 2>
Y-type zeolite was used as the malodorous gas adsorbent.

<Comparative Example 3>
ZSM-5 type zeolite was used as a malodorous gas adsorbent.

<Comparative Example 4>
A zirconium hydroxide was obtained by preparing an aqueous solution in which a soluble zirconium salt and a soluble hafnium salt were dissolved in water, adding a base thereto to generate a hydroxide, and then separating and recovering the hydroxide. The resulting zirconium hydroxide was used as a malodorous gas adsorbent.

Table 1 shows the malodorous gas adsorbents of Examples and Comparative Examples. When the porous metal complex was used as the malodorous gas adsorbent, the maximum pore size and primary particle size of the porous metal complex were measured. The measuring method is as follows. Table 1 shows the measurement results.

(maximum pore diameter)
It was measured using model number "AUTOSORB-1" (manufactured by Quantachrome Instruments).

(Primary particle size)
The porous organometallic complex was observed at an appropriate magnification using a semi-in-lens scanning electron microscope (product name “S-4800”, manufactured by Hitachi High-Technologies Corporation). Particles were identified based on the obtained SEM image. The diameter of the longest part of the particle was measured on the SEM image at a magnification at which a single particle was observable. 100 particles were measured, and the average value was taken as the primary particle size.

Using the malodorous gas adsorbents of Examples and Comparative Examples, the acetic acid gas adsorption capacity was calculated. The calculation method is as follows. Table 2 shows the results. Incidentally, if the acetic acid gas adsorption capacity is 50 mL/g or more, it is at a practically acceptable level.

(1) The malodorous gas adsorbent was sealed in a vinyl alcohol polymer film bag, and the bag was filled with air to a volume of 3 liters.
(2) The specific gas was put into this bag so that the concentration of the specific gas was 30 ppm.
(3) After 30 minutes, the concentration of the specific gas remaining in the bag was measured with a gas detector tube, and then 30 ppm of the specific gas was added to the bag.
(4) After another 30 minutes, the concentration of the specific gas remaining in the bag was measured with a gas detector tube.
(5) Until the concentration of the specific gas in the bag does not decrease (that is, after 30 minutes, it is confirmed that the concentration of the remaining specific gas is 30 ppm higher than the concentration of the specific gas obtained in the immediately preceding measurement. until) the above operations (2) and (3) were repeated.
(6) The point at which the gas concentration stopped decreasing was regarded as the limit point of the amount of specific gas that could be adsorbed by the malodorous gas adsorbent (that is, the end point of the test), and the operation of supplying the specific gas was stopped.
The acetic acid gas adsorption capacity of the malodorous gas adsorbent was calculated based on the following formula.
Gas adsorption capacity (mL/g) = [{Number of gas injections up to the test end point x 30 (ppm) - residual gas amount (ppm) at the end of the test} x 3000 (mL) x 1/1000000] / used for measurement Amount of bad smell gas adsorbent (g)

As shown in Table 2, the malodorous gas adsorbents of Examples 1 and 2 have a higher adsorption capacity for acetic acid gas and a higher adsorption capacity for acidic gases than the malodorous gas adsorbent of Comparative Example 1. Do you get it.

Next, using the malodorous gas adsorbents of Examples and Comparative Examples, the deodorizing rate was calculated. The calculation method is as follows. Table 3 shows the results.

20 mg of the malodorous gas adsorbent was placed in a vinyl alcohol polymer film bag and sealed. The bag was inflated to a volume of 3L. Acetic acid gas was put into this bag so that the acetic acid gas concentration was 500 ppm, and the bag was allowed to stand for 24 hours. Two hours after the injection of acetic acid gas, the residual acetic acid gas concentration in the bag was measured with a gas detector tube. Based on the following formula, the deodorizing rate of the malodorous gas adsorbent was calculated.
Deodorant rate (%) = [{500-(residual acetic acid gas concentration)} (ppm) / (500 ppm)] × 100

As shown in Table 3, the malodorous gas adsorbents of Examples 1 and 2 have a higher deodorizing rate and an acidic gas adsorption capacity than the malodorous gas adsorbents of Comparative Examples 1 to 4. It turned out to be expensive.

Next, the deodorant rate was calculated using the deodorant resin compositions containing the malodorous gas adsorbents of Examples and Comparative Examples. The calculation method is as follows. The results are shown in Tables 4 and 5.

Using an injection molding machine, polyester (product name "MA2101M", manufactured by Unitika) and a bad smell gas adsorbent were kneaded and molded into a plate shape at 280°C. A deodorizing resin composition was obtained by adjusting the amount of the malodorous gas adsorbent added to 3 parts by mass per 100 parts by mass of the polyester.

The deodorant resin composition obtained by molding was pulverized with a blender. 1.0 g of the pulverized product was placed in a vinyl alcohol polymer film bag and sealed. The bag was inflated to a volume of 3L. Acetic acid gas was put into the bag so that the concentration of acetic acid gas was 30 ppm, and the bag was allowed to stand. Two hours after the injection of acetic acid gas, the residual acetic acid gas concentration in the bag was measured with a gas detector tube. Based on the following formula, the deodorant rate of the deodorant resin composition containing the malodorous gas adsorbent was calculated.
Deodorant rate (%) = [{30-(residual acetic acid gas concentration)} (ppm) / (30 ppm)] × 100

Using an injection molding machine, polyester (product name "MA2101M", manufactured by Unitika) and a bad smell gas adsorbent were kneaded and molded into a plate shape at 280°C. A deodorizing resin composition A was obtained by adjusting the amount of the malodorous gas adsorbent to be added to 2 parts by mass with respect to 100 parts by mass of the polyester resin.

Using an injection molding machine, polypropylene (product name "Prime Polypro J707G", manufactured by Prime Polymer) and a bad smell gas adsorbent were kneaded and molded into a plate shape at 220°C. A deodorant resin composition B was obtained by adjusting the amount of the malodorous gas adsorbent added to 2 parts by mass with respect to 100 parts by mass of the polypropylene resin.

Using an injection molding machine, polyethylene (product name "Hi-Zex 2100J", manufactured by Prime Polymer) and a bad smell gas adsorbent were kneaded and molded into a plate shape at 220°C. A deodorant resin composition C was obtained by adjusting the amount of the malodorous gas adsorbent added to 2 parts by mass per 100 parts by mass of the polyethylene resin.

An injection molding machine kneaded acrylic resin (product name "Acrypet VHS", manufactured by Mitsubishi Chemical) and a bad smell gas adsorbent, and molded it into a plate shape at 240°C. A deodorizing resin composition D was obtained by adjusting the amount of the malodorous gas adsorbent to be added to 2 parts by mass with respect to 100 parts by mass of the acrylic resin.

The deodorant resin compositions A to D obtained by molding were cut into pieces of 5 mm x 5 mm. 2.0 g of the cut sample was placed in a vinyl alcohol polymer film bag and sealed. The bag was inflated to a volume of 3L. Acetic acid gas was put into the bag so that the concentration of acetic acid gas was 30 ppm, and the bag was allowed to stand. After 2 hours and 24 hours from the injection of acetic acid gas, the residual acetic acid gas concentration in the bag was measured with a gas detector tube. The deodorant rate of the deodorant resin compositions A to D containing the malodorous gas adsorbent was calculated in the same manner as in the method for calculating the deodorant rate. Table 5 shows the results.

As shown in Tables 4 and 5, in the deodorant resin composition containing the malodorous gas adsorbent of Example 1, compared with the deodorant resin composition containing the malodorous gas adsorbent of Comparative Example 4, the deodorizing rate was It was found that the adsorption capacity for acidic gases is high.

Next, using deodorant resin composition B and deodorant resin composition C containing the bad smell gas adsorbent of Example 1, MFR (melt flow rate) was measured. The stability of the resin composition containing the malodorous gas adsorbent was evaluated based on MFR. The evaluation method is as follows.

The MFR of the deodorant resin composition B was measured using a melt indexer (product name "Melt Indexer G-02", manufactured by Toyo Seiki Co., Ltd.) at 230 ° C. and a load of 2.16 kg in accordance with JIS K 7210-1: 2014. measured in As a blank sample, a polypropylene (product name: "Prime Polypro J707G", manufactured by Prime Polymer) was molded into a plate at 220°C by an injection molding machine.

Using a melt indexer (product name "Melt Indexer G-02", manufactured by Toyo Seiki Co., Ltd.), it was measured at 190°C and a load of 2.16 kg in accordance with JIS K 7210-1:2014. As a blank sample, polyethylene (product name: "Hi-Zex 2100J", manufactured by Prime Polymer) was molded into a plate shape at 220°C by an injection molding machine. Table 6 shows the evaluation results.

As shown in Table 6, the deodorant resin composition containing the malodorous gas adsorbent of Example 1 showed no significant change in MFR compared to the blank sample containing no malodorous gas, indicating excellent stability. Do you get it.

<Example 3>
A porous organometallic complex (ZIF-8) was obtained in the same manner as in Example 1. Next, 1.0 g of a porous organometallic complex (ZIF-8) and 1.0 g of porous silica (median diameter: 2.8 μm, specific surface area: 500 m ² /g), which is a porous material, are placed in a vial and mixed. and shaken well to obtain a malodorous gas adsorbent which is a mixture of porous organometallic complex (ZIF-8) and porous silica in a mass ratio of 1:1.
FIG. 3 shows a scanning electron microscope (SEM) photograph of the obtained malodorous gas adsorbent. As a scanning electron microscope, a product name "S-4800" manufactured by Hitachi High-Technologies Corporation was used. The magnification of the photograph was 50000 times, and the SEM photograph was obtained using a voltage of 1.0 KV. From FIG. 3, it was found that the primary particle size of ZIF-8 was mainly around 0.1 μm.

<Example 4>
0.9 g of zinc nitrate was added to 20 mL of pure water to prepare an aqueous zinc nitrate solution. After that, 0.9 g of porous silica (median diameter: 2.8 μm, specific surface area: 500 m ² /g), which is a porous material, is added to the zinc nitrate aqueous solution and stirred to uniformly distribute the porous silica in the zinc nitrate aqueous solution. dispersed. Next, 10 g of 2-methylimidazole as a ligand was added to 35 mL of pure water to prepare an aqueous 2-methylimidazole solution. The 2-methylimidazole aqueous solution was added to the zinc nitrate aqueous solution in which the porous silica was dispersed, and the mixture was stirred at 25° C. for 10 minutes. The obtained reaction solution was filtered, and the filtered solid matter was washed with pure water. The washed solid was dried overnight at 80° C. and then pulverized in a mortar to obtain a composite of porous organometallic complex (ZIF-8) and porous silica. In SEM observation of the composite, it was observed that the porous organometallic complex (ZIF-8) coated the surface of the porous silica. The surface coverage of the porous silica was 80% or more, and the porous metal complex (ZIF-8) was supported on the porous silica. This complex was dissolved in a strong acid and subjected to ICP emission spectroscopic analysis to determine the ratio of Zn and Si. As a result, the mass ratio of the porous organometallic complex (ZIF-8) and porous silica was 1:1. rice field. This composite was used as a malodorous gas adsorbent.
FIG. 4 shows an SEM photograph of the obtained malodorous gas adsorbent. As a scanning electron microscope, a product name "S-4800" manufactured by Hitachi High-Technologies Corporation was used. The magnification of the photograph was 50000 times, and the SEM photograph was obtained using a voltage of 1.0 KV. From FIG. 4, it was found that the primary particle size of ZIF-8 was mainly around 0.2 μm.
XMA analysis was performed in SEM observation, and the coated particles were identified as ZIF-8. In the XMA analysis, JSM-7900E (manufactured by JEOL Ltd.) and Ultim Max100 (manufactured by Oxford Instruments) were used to perform elemental mapping of the complex at an acceleration voltage of 2.5 KV.

<Example 5>
A porous organometallic complex (ZIF-8) was obtained in the same manner as in Example 1. Next, 1.0 g of a porous organometallic complex (ZIF-8) and 1.0 g of ZSM-5 type zeolite (median 4.0 μm, specific surface area 390 m ² /g), which is a porous material, were placed in a vial. They were mixed and shaken well to obtain a malodorous gas adsorbent which was a mixture of porous metal complex (ZIF-8) and ZSM-5 type zeolite at a mass ratio of 1:1.
FIG. 5 shows an SEM photograph of the obtained malodorous gas adsorbent. As a scanning electron microscope, a product name "S-4800" manufactured by Hitachi High-Technologies Corporation was used. The magnification of the photograph was 10000 times, and the SEM photograph was obtained using a voltage of 1.0 KV. From FIG. 5, it was found that the primary particle size of ZIF-8 was mainly around 0.2 μm.

<Example 6>
First, 0.9 g of zinc nitrate was added to 20 mL of pure water to prepare a zinc nitrate aqueous solution. After that, 0.9 g of ZSM-5 type zeolite (median diameter 4.0 μm, specific surface area 390 m ² /g), which is a porous material, is added to the zinc nitrate aqueous solution and stirred, and ZSM-5 type zeolite is added to the zinc nitrate aqueous solution. The zeolite was evenly dispersed. Next, 10 g of 2-methylimidazole was added to 35 mL of pure water to prepare an aqueous 2-methylimidazole solution. The 2-methylimidazole aqueous solution was added to the zinc nitrate aqueous solution in which the ZSM-5 type zeolite was dispersed, and the mixture was stirred at 25° C. for 10 minutes. The obtained reaction solution was filtered, and the filtered solid matter was washed with pure water. The washed solid was dried overnight at 80° C. and then pulverized in a mortar to obtain a composite of porous organometallic complex (ZIF-8) and ZSM-5 type zeolite. In SEM observation of the composite, it was observed that the porous organometallic complex (ZIF-8) coated the surface of the zeolite. The surface coverage of the ZSM-5 zeolite was 90% or more, and the porous organometallic complex (ZIF-8) was supported on the ZSM-5 zeolite. This composite was used as a malodorous gas adsorbent.
FIG. 6 shows an SEM photograph of the obtained malodorous gas adsorbent. As a scanning electron microscope, a product name "S-4800" manufactured by Hitachi High-Technologies Corporation was used. The magnification of the photograph was 10000 times, and the SEM photograph was obtained using a voltage of 1.0 KV. From FIG. 6, it was found that the primary particle size of ZIF-8 was mainly around 0.2 μm.
3 to 6, 1 indicates silica, 2 indicates ZIF-8, and 3 indicates zeolite.

Using the malodorous gas adsorbents of Examples 1, 3 to 6 and Comparative Examples 3 and 5, the acetic acid gas adsorption capacity and deodorization rate were calculated. The method for calculating the acetic acid gas adsorption capacity is as described above. The method for calculating the deodorant rate is as follows. Deliquescence resistance was also evaluated using the malodorous gas adsorbents of Examples and Comparative Examples. The evaluation method is as follows. Table 7 shows the results.

(Deodorant rate)
20 mg of the malodorous gas adsorbent was placed in a vinyl alcohol polymer film bag and sealed. The bag was inflated to a volume of 3L. Acetic acid gas was put into this bag so that the acetic acid gas concentration was 600 ppm, and the bag was allowed to stand for 24 hours. Two hours after the injection of acetic acid gas, the residual acetic acid gas concentration in the bag was measured with a gas detector tube. The deodorizing rate of each gas adsorbent was calculated based on the following formula.
Deodorant rate (%) = {600-(residual acetic acid gas concentration)} (ppm) / (600 ppm) x 100

(Deliquescence resistance)
1. Change in Appearance 20 mg of the malodorous gas adsorbent was placed in a vinyl alcohol polymer film bag and sealed. Air with a humidity of 40% was put into the bag so that the volume was 3 L. Acetic acid gas was put into this bag so that the acetic acid gas concentration was 600 ppm, and the bag was allowed to stand in an environment of 25° C. for 24 hours. After 24 hours, the appearance was visually inspected and evaluated according to the following indices.
A: The appearance of the malodorous gas adsorbent after 24 hours does not deliquesce, and the solid malodorous gas adsorbent remains free-flowing.
B: After 24 hours, the appearance of the malodorous gas adsorbent did not change significantly, and the surface did not have stickiness, but a change as if the surface had absorbed moisture was observed.
C: After 24 hours, the malodorous gas adsorbent was deliquesced and had a smooth appearance, did not maintain a solid state, and had a sticky surface.

2. Weight Gain Weight gain due to deliquescence was measured by the following method.
1) A vinyl alcohol polymer film was cut into a size of 2 cm x 2 cm.
(2) The cut film was placed on an aluminum cup, and the malodorous gas adsorbent was spread thinly and placed thereon.
(3) Before and after placing the malodorous gas adsorbent, the total weight of each was measured.
(4) (2) was placed in a vinyl alcohol polymer film bag.
(5) 100 mL of air (40% humidity) and acetic acid gas were injected with a syringe so that the concentration of acetic acid gas was 15000 ppm.
(6) Allowed to stand for 24 hours in a constant temperature machine at 40°C.
(7) After 24 hours, the aluminum cup was taken out and the total weight was measured. The weight change before and after the test was obtained based on the following formula.
Increased amount (g) per gram of malodorous gas adsorbent = {(Weight of malodorous gas adsorbent after 24 hours of acetic acid gas injection (g)) - (Weight of malodorous gas adsorbent before acetic acid gas injection (g))} ÷ (weight (g) of malodorous gas adsorbent before injection of acetic acid gas)

As shown in Table 7, it was found that the malodorous gas adsorbents of Examples 3 and 5 exhibit excellent adsorption capacity and deodorizing rate for acetic acid gas, and also exhibit extremely excellent deliquescence resistance. Furthermore, Examples 4 and 6, which are composites in which a porous organometallic complex is supported on a porous material, are composites in which a corresponding porous organometallic complex and a porous material are mixed, respectively. As compared with Example 5, all of them were found to be superior in deliquescence resistance and more practical.

In addition, Japanese Patent Application No. 2021-050148 filed on March 24, 2021, Japanese Patent Application No. 2021-050149 filed on March 24, 2021, and filed on January 31, 2022 The disclosure of Japanese Patent Application No. 2022-013507 filed is incorporated herein by reference in its entirety. In addition, all publications, patent applications and technical standards mentioned herein are to the same extent as if each individual publication, patent application and technical standard were specifically and individually noted to be incorporated by reference. , incorporated herein by reference.

Claims

A malodorous gas adsorbent containing a porous organometallic complex containing a metal and a ligand containing a nitrogen atom.
The malodorous gas adsorbent according to claim 1, wherein the metal is at least one selected from the group consisting of Zn, Zr, Ti, Al, and Co.
The malodorous gas adsorbent according to claim 1 or claim 2, wherein the ligand containing a nitrogen atom has an aromatic ring or a heterocyclic ring.
The malodorous gas adsorbent according to any one of claims 1 to 3, wherein the metal is Zn and the ligand is an imidazole compound.
The malodorous gas adsorbent according to any one of claims 1 to 4, which is used for adsorbing acid gases.
The malodorous gas adsorbent according to any one of claims 1 to 5, wherein the porous organometallic complex is a particle having a primary particle size of 0.05 µm to 3.0 µm.
The malodorous gas adsorbent according to any one of claims 1 to 6, which has a gas adsorption capacity of 50 mL/g or more.
The malodorous gas adsorbent according to any one of claims 1 to 7, further comprising a porous material.
The malodorous gas adsorbent according to claim 8, wherein the porous organometallic complex is supported on the porous material.
The malodorous gas adsorbent according to claim 8 or claim 9, wherein the porous material contains at least one selected from the group consisting of porous metal oxides, zeolites, and activated carbon.
20 mg of the malodorous gas adsorbent does not deliquesce in 3 liters of acetic acid gas with a concentration of 600 ppm prepared in air with a humidity of 40% in an environment of 25° C. for 24 hours. 2. The malodorous gas adsorbent according to item 1.
40 mg of the malodorous gas adsorbent was exposed to 300 mL of acetic acid gas with a concentration of 15000 ppm prepared in air with a humidity of 40% for 24 hours in an environment of 40°C.
The malodorous gas adsorbent according to any one of claims 8 to 11, wherein the amount of increase per 1g of the malodorous gas adsorbent after 24 hours is 0.35 g or less.
A deodorant product containing the malodorous gas adsorbent according to any one of claims 1 to 12.
mixing a solution containing a metal salt with a solution containing a porous material and a ligand containing nitrogen atoms;
and a step of solid-liquid separation from the mixed liquid obtained by mixing to obtain a solid matter.