JP2006051486A - Adsorbent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adsorbent having a high adsorption performance for a poisonous gas, especially an aldehyde based gas, excellent in heat resistance and also excellent in transparency. <P>SOLUTION: The adsorbent is obtained by supporting a compound having an amino group on porous inorganic powder mainly composed of zinc phosphate shown by the following compositional formula 1. The compositional formula 1 is Zn<SB>k</SB>X<SB>l</SB>(PO<SB>4</SB>)<SB>m</SB>Y<SB>n</SB>-oH<SB>2</SB>O, wherein X is a metal ion of the valence of p(p=2 or 3), Y is an anion of the valence of q(q=1, 2 or 3), k, l, m and n are a real number satisfying 2k+p×1-(3m+q×n)=0(wherein, k and m are a positive real number and l and n are a positive real number), and o is a real number of ≥0. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an adsorbent obtained by supporting a compound having an amino group on a porous inorganic powder containing zinc phosphate as a main component, and particularly having high adsorbability for an aldehyde-based gas.

In recent years, interest in bad odors and harmful gases present in living spaces has increased.
Among numerous odors and harmful gases, there is a growing interest in aldehyde-based gases such as acetaldehyde, which is the main component of tobacco odor, and formaldehyde that causes sick house syndrome. Adsorbents are being developed.

  For example, Patent Document 1 describes that an adsorbent obtained by attaching an amine compound to activated carbon is excellent in aldehyde-based gas removal ability.

JP 60-48138 A

However, when an organic carrier such as activated carbon is used, there is a problem in heat resistance.
Furthermore, since activated carbon itself is colored, there is also a problem that when it is applied to a living space such as an interior material, the appearance style of the living space is limited.

  In order to solve the above-mentioned problems, the present invention has been intensively studied. As a result, a porous inorganic powder mainly composed of zinc phosphate carries a compound having an amino group, in particular, an aldehyde gas. It was found that an adsorbent having a high adsorptive capacity, excellent heat resistance and excellent transparency can be obtained.

That is, the present invention has the following features.
1. An adsorbent comprising a porous inorganic powder mainly composed of zinc phosphate represented by the following composition formula 1 and a compound having an amino group supported thereon.
(Composition Formula 1)
_{Zn k X l (PO 4)} m Y n · oH 2 O
(X is a p-valent metal ion (p is 2 or 3), Y is a q-valent anion (q is 1, 2 or 3), k, l, m, n are 2k + p × l− (3m + q × n) = Real number satisfying 0 (where k and m are positive real numbers, l and n are 0 or positive real numbers), o is a real number of 0 or more)
2. 1. A compound having an amino group is supported on a porous inorganic powder in an amount of 0.1 to 30 wt%. Adsorbent according to.
3. The average particle size is 0.01 to 100 μm. Or 2. The adsorbent according to any one of the above.
4). 1. Specific surface area is 10 m ² / g or more To 3. The adsorbent according to any one of the above.

The adsorbent of the present invention has a high removal ability especially for aldehyde-based gas and has excellent heat resistance. Moreover, since it is excellent in transparency, there is no coloring by an adsorbent and it can be widely applied to various uses. For example, when the adsorbent of the present invention is applied to various members such as interior materials, it is possible to perform a beautification design that makes use of the material feeling of the various members.
Furthermore, the porous inorganic powder mainly composed of zinc phosphate used in the adsorbent of the present invention is inexpensive and non-polluting and exhibits excellent anticorrosion performance.
Such an adsorbent of the present invention also has environmental purification effects such as deodorization and air pollution purification.

  Hereinafter, the best mode for carrying out the present invention will be described in detail.

  The present invention is an adsorbent obtained by supporting a compound having an amino group on a porous inorganic powder mainly composed of zinc phosphate represented by the following composition formula 1.

(Composition Formula 1)
_{Zn k X l (PO 4)} m Y n · oH 2 O
(X is a p-valent metal ion (p is 2 or 3), Y is a q-valent anion (q is 1, 2 or 3), k, l, m, n are 2k + p × l− (3m + q × n) = Real number satisfying 0 (where k and m are positive real numbers, l and n are 0 or positive real numbers), o is a real number of 0 or more)

X is a divalent or trivalent metal ion, for example, a divalent metal ion such as Mg ²⁺ , Ca ²⁺ , Sr ²⁺ , Ba ²⁺ , Co ²⁺ , Ni ²⁺ , Cu ²⁺ , Al ³⁺ , Bi ³⁺ , Co ³⁺ , Mn ³⁺ , Fe ^{3+ and} other trivalent metal ions.
In particular, when X is a metal ion such as Mg ²⁺ , Ca ²⁺ , and Al ³⁺ , it is desirable because it is inexpensive and excellent in transparency.
Y is a monovalent, divalent, or trivalent anion, and examples thereof include OH ⁻ , CH ₃ COOH ⁻ , SO ₄ ²⁻ , Cl ⁻ , NO ₃ ⁻ , CO ₃ ^{2− and the} like.

k, l, m, and n are not particularly limited as long as they are real numbers satisfying 2k + p × l− (3m + q × n) = 0 (where k and m are positive real numbers and l and n are 0 or positive real numbers). However, k: l = 10: 0-10: 8 (preferably 10: 0-10: 6), k: m = 8: 2-2: 8, m: n = 10: 0-4: 6 It is preferable that
Note that k, l, m, and n can be obtained by elemental analysis (EDS).

  In the present invention, by using a porous inorganic powder mainly composed of zinc phosphate, an adsorbent that is inexpensive and non-polluting and has excellent heat resistance, transparency, and anticorrosion performance can be obtained. .

  Moreover, the porous inorganic powder of this invention can also use a single zinc phosphate, and can also select and use the mixture of 2 or more types of zinc phosphates suitably.

Such an inorganic powder is essential to be porous. Specifically, the specific surface area is preferably 10 m ² / g or more, more preferably 15 m ² / g or more.
By being a porous inorganic powder, it is excellent in gas adsorbing ability, and can increase the amount of a compound having an amino group, which will be described later, to obtain an adsorbent that is particularly excellent in removing ability for aldehyde-based gas. be able to.

The average particle size of the porous inorganic powder is not particularly limited, but is preferably 0.01 μm to 100 μm, more preferably 0.1 μm to 50 μm. By being in such a range, while exhibiting excellent gas adsorption capacity, it has more excellent transparency.
The particle size distribution, particle shape, etc. of the porous inorganic powder may be set as appropriate.

It does not specifically limit as a method of obtaining zinc phosphate, It can manufacture by a well-known method. For example, the following methods are mentioned.
1. A method of obtaining zinc phosphate by a coprecipitation method from a mixed solution containing zinc ions and phosphate ions as a solute (coprecipitation method).
2. A method in which an anion of a zinc compound is partially or completely substituted with a phosphate ion (substitution method).

(Coprecipitation method)
In the method for producing zinc phosphate by the coprecipitation method of the present invention, a basic solution is added to a mixed solution containing zinc ions and phosphate ions as a solute to precipitate zinc phosphate.
In such a coprecipitation method, since zinc phosphate precipitates rapidly, it is estimated that the crystal growth of zinc phosphate is completed incompletely and porous zinc phosphate is obtained.

A mixed solution containing zinc ions and phosphate ions as a solute (hereinafter also simply referred to as “mixed solution”) is obtained by dissolving a zinc compound, phosphoric acid and / or phosphate in a solvent. The mixed solution may be prepared by separately preparing a solution in which a zinc compound is dissolved and a solution in which phosphoric acid and / or a phosphate are dissolved, and then mixing the zinc compound and phosphoric acid and / or a phosphate. May be prepared by dissolving in the same solvent.
Especially as a solvent, alcohol, such as water, methanol, ethanol, butanol, etc. can be used conveniently.

  In such a mixed solution, it is essential that zinc ions and phosphate ions are used as solutes. However, the above-described divalent or trivalent metal ions and monovalent ions are within the range that gives the composition of (composition formula 1). A divalent or trivalent anion may coexist.

Moreover, as a mixed solution, in order that zinc ion and phosphate ion will melt | dissolve stably, it is desirable that pH is 7 or less, More preferably, it is 6 or less, More preferably, it is 5 or less.
Moreover, in order to adjust pH of a mixed solution, you may add an acid and an alkali.

  The acid at this time is not particularly limited and known acids can be used. For example, hydrochloric acid, nitric acid, acetic acid, sulfuric acid, formic acid, acetic acid, propionic acid, butanoic acid, butyric acid, succinic acid, malonic acid, citric acid , Tartaric acid, gluconic acid, salicylic acid, benzoic acid, acrylic acid, maleic acid, glyceric acid, eleostearic acid, polyacrylic acid, polymaleic acid, acrylic acid-maleic acid copolymer carboxylic acid, polycarboxylic acid, etc. it can.

  As the alkali, for example, ammonia, urea, potassium hydroxide, calcium hydroxide, sodium hydroxide, magnesium hydroxide, sodium carbonate, potassium carbonate and the like can be used.

  The zinc ion concentration and phosphate ion concentration of each of a solution in which a zinc compound is dissolved, a solution in which phosphoric acid and / or phosphate are dissolved, and a mixed solution in which zinc ions and phosphate ions are solutes are not particularly limited. A solution having a concentration up to the solubility limit can be used.

The zinc compound is not particularly limited, and examples thereof include zinc chloride, zinc sulfate, zinc nitrate, zinc acetate, zinc oxide, zinc formate, zinc lactate, and basic zinc carbonate. Among these, zinc chloride, zinc sulfate, zinc nitrate and the like are preferable because they are inexpensive and can provide a stable supply.
Moreover, although it is essential for a zinc compound to use a zinc ion as a component, at least one or more of the above-described divalent or trivalent metal ions may be included as a component.

Examples of phosphoric acid and / or phosphate include phosphoric acid, disodium hydrogen phosphate, sodium dihydrogen phosphate, trisodium phosphate, dipotassium hydrogen phosphate, potassium dihydrogen phosphate, tripotassium phosphate, Examples thereof include diammonium hydrogen phosphate, ammonium dihydrogen phosphate, triammonium phosphate, calcium hydrogen phosphate, and the like. Among them, those that are easily soluble in water and give an acidic phosphoric acid or phosphate solution include phosphoric acid, sodium dihydrogen phosphate, potassium dihydrogen phosphate, ammonium dihydrogen phosphate, etc. It is preferable to use it.
Moreover, as phosphoric acid and / or a phosphate, it is essential that a phosphate ion is a component, but at least one or more of the above-described monovalent, divalent, or trivalent anions are used as a component. May be included.

  The base solution is not limited, but is a solution in which at least one base selected from ammonia, urea, potassium hydroxide, calcium hydroxide, sodium hydroxide, magnesium hydroxide, sodium carbonate, potassium carbonate and the like is dissolved in a solvent. Can be used. The concentration of these base solutions is not limited, and solutions up to the concentration limit can be used.

  The temperature at which the base solution is added to the mixed solution containing zinc ions and phosphate ions as a solute is preferably 0 ° C to 100 ° C, more preferably 5 ° C to 60 ° C, more preferably 5 ° C to 50 ° C. . By being in such a temperature range, loss of porosity due to complete crystal growth of zinc phosphate can be suppressed. If the temperature is higher than this range, the aggregation between particles proceeds greatly and the porosity disappears, so that a porous powder having good dispersibility and a large specific surface area cannot be obtained.

(Substitution method)
In the method for producing zinc phosphate by the substitution method of the present invention, phosphoric acid and / or a phosphate solution is added to a slurry in which a zinc compound is mixed, and the anion of the zinc compound is completely or partially substituted with phosphate ions. To do.
In the substitution method, when the anion of the zinc compound is replaced by a phosphate ion, the vacancy on the crystal surface caused by the elution of the anion of the zinc compound is not completely filled with the phosphate ion, so that the porous phosphorus It is estimated that zinc acid is obtained.

The zinc compound used in the substitution method preferably has poor solubility in water, and among the above-mentioned zinc compounds, it is preferable to use zinc oxide or basic zinc carbonate.
As the phosphoric acid and / or phosphate used in the substitution method, phosphoric acid, sodium dihydrogen phosphate, potassium dihydrogen phosphate, which are easily soluble and give an acidic phosphoric acid or phosphate solution, It is preferable to use ammonium dihydrogen phosphate or the like.

  When adding the phosphoric acid and / or phosphate solution to the slurry mixed with the zinc compound, the temperature is preferably 0 ° C to 100 ° C, more preferably 4 ° C to 60 ° C, more preferably 4 ° C to 50 ° C. . By being in such a temperature range, loss of porosity due to complete crystal growth of zinc phosphate can be suppressed.

  The zinc phosphate produced by the coprecipitation method and the substitution method can be obtained by washing with a volatile organic solvent such as water, alcohols and acetone after the precipitation and drying. The drying method at this time may be performed at 50 ° C. to 120 ° C. in the air, or may be performed by a freeze drying method or a vacuum drying method.

In the coprecipitation method and the substitution method, an organic dispersant may be added for the purpose of improving the dispersibility of the manufactured zinc phosphate.
In the coprecipitation method, the organic dispersant is preferably added before adding the base to the mixed solution containing zinc ions and phosphate ions as solutes. Further, in the substitution method, it is desirable to add the zinc compound slurry before adding the phosphoric acid and / or phosphate aqueous solution.

  As the organic dispersant, those having water solubility are preferable, for example, alcohols, polyols, ketones, polyethers, esters, celluloses, saccharides, sulfonic acids, higher fatty acids, higher fatty acid salts, higher fatty acid salts. Examples thereof include phosphate esters of fatty acid alcohols, phosphoric acid and salts thereof, waxes, anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants, and coupling agents.

  More specifically, aliphatic alcohols such as methanol, ethanol, propanol, butanol, pentanol and hexanol, aliphatic polyhydric alcohols such as ethylene glycol, propanediol, butanediol, glycerin, polyethylene glycol and polypropylene glycol, phenol and catechol , Aromatic alcohols such as cresol, alcohols having a heterocyclic ring such as furyl alcohol, ketones such as acetone, methyl ethyl ketone, acetylacetone, ethyl ether, tetrahydrofuran, dioxane, polyoxyalkylene ether, ethylene oxide adduct, propylene oxide adduct Ethers or polyethers such as ethyl acetate, ethyl acetoacetate, glycine ethyl ester, carboxymethyl Ruloses, monosaccharides such as glucose, galactose, polysaccharides such as sucrose, lactose, amylose, chitin, cellulose, alkylbenzene sulfonic acid, paratoluene sulfonic acid, alkyl sulfonic acid, α-olefin sulfonic acid, polyoxyethylene alkyl sulfonic acid Sulfonic acids such as lignin sulfonic acid and naphthalene sulfonic acid and salts thereof, higher fatty acids such as lauric acid, palmitic acid, oleic acid, stearic acid, capric acid, myristic acid, linoleic acid and polycarboxylic acid, lithium of the above higher fatty acids Higher fatty acid salts such as salts with alkali metals such as salts, sodium salts and potassium salts, phosphate esters of higher fatty acid alcohols, for example, alkyl ethers such as lauryl ether phosphoric acid, stearyl ether phosphoric acid, and oleyl ether phosphoric acid. Higher fatty acids such as telluric acid, dialkyl ether phosphoric acid, alkyl phenyl ether phosphoric acid, dialkyl phenyl ether phosphoric acid, etc., or alkyl ether phosphates such as sodium oleyl ether phosphate and potassium stearyl ether phosphate, hexametaphosphoric acid and salts thereof -Based alcohol phosphates, coconut oil fatty acid monoethanolamide, alkylolamides such as lauric acid diethanolamide, polyoxyalkylphenyl ethers such as polyoxyethylene alkylphenyl ether, polyoxyethylene such as polyoxyethylene lauryl ether Ethylene alkyl ethers, polyethylene glycol fatty acid esters such as polyethylene glycol distearate, sorbitan monocaprate, monostearate Sorbitan fatty acid esters such as sorbitan acid and sorbitan distearate, polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monostearate, polyoxyethylene sorbit fatty acid esters, polyoxyethylene polyoxypropylene alkyl ethers, glycol ethers Nonionic surfactants such as, alkyltrimethylammonium salts such as lauryltrimethylammonium chloride, cetyltrimethylammonium bromide, stearyltrimethylammonium chloride, alkyl such as stearyldimethylbenzylammonium chloride, benzalkonium chloride, lauryldimethylbenzylammonium chloride Cationic surfactants such as dimethylbenzylammonium salts, palm oil alkyl beties Alkyl betaines such as lauryl dimethylaminoacetic acid betaine, imidazolines such as Z-alkyl-N-carboxymethyl-N-hydroxyethyl imidazole betaine, glycines such as polyoctyl polyaminoethyl glycine, etc. Examples include amphoteric activators, silane coupling agents, aluminum coupling agents, titanium coupling agents, and other coupling agents such as zirconium coupling agents, and one or more of these are used. be able to.

In the present invention, aliphatic alcohols such as methanol, ethanol, propanol, butanol, pentanol, and hexanol, and aliphatic polyhydric alcohols such as ethylene glycol, propanediol, butanediol, glycerol, polyethylene glycol, and polypropylene glycol are used. Is preferred.
By using such a dispersant, it is possible to control the growth of particles at the time of zinc phosphate production, and as a result, it is possible to control the crystal shape, the average particle diameter, etc., and to produce fine particles having a uniform size. It seems to be possible.
The addition amount of these dispersing agents is 0.05-15 wt% with respect to the weight of the zinc phosphate powder to produce | generate, Preferably it is the range of 0.1-10 wt%. If it is less than this range, the addition effect of a dispersing agent will be small.

The compound having an amino group of the present invention enhances the gas adsorption ability by chemically bonding with a harmful gas, particularly an aldehyde-based gas.
Examples of the compound having an amino group include aliphatic amines, aromatic amines, alicyclic amines, amino acids and amino acids, or silicon compounds having an amino group.
Specifically, methylamine, ethylamine, propylamine, isopropylamine, butylamine, amylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, pentadecyl Aliphatic amines such as amine, cetylamine, tetraethylenepentamine, diethylenetriamine,
Aniline, methylaniline, dimethylaniline, ethylaniline, diethylaniline, o-toluidine, m-toluidine, p-toluidine, benzylamine, dibenzylamine, tribenzylamine, diphenylamine, triphenylamine, α-naphthylamine, β-naphthylamine Aromatic amines, etc.
Cycloaliphatic amines such as cyclopropylamine, cyclobutylamine, cyclopentylamine, cyclohexylamine,
Amino acids and amino acids such as hexamethylenetetraming lysine, glutamic acid, aspartic acid, alanine, trimethylaminoethylalkylamide, alkylpyridinium sulfate, alkyltrimethylammonium halide, alkylbetaine, alkyldiethylenetriaminoacetic acid,
γ-aminopropyltrimethoxysilane, N-β (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β (aminoethyl) -γ-aminopropyltriethoxysilane, γ-glycidoxypropyltriethoxysilane, Examples thereof include silicon compounds having an amino group such as dimethyltrimethyl-silylamine.
These organic compounds having an amino group can be used alone or in combination of two or more.
In the present invention, it is preferable to use an aliphatic amine or a silicon compound having an amino group, and it is more preferable to use a silicon compound having an amino group. When a silicon compound having an amino group is used, it is easily chemically bonded to the porous inorganic powder. For this reason, it is easy to carry | support to the porous inorganic powder firmly, it can suppress that the silicon compound which has an amino group from porous inorganic powder detachment | desorption, and can suppress the discoloration by an amine.

The adsorbent of the present invention is formed by supporting a compound having an amino group on a porous inorganic powder mainly composed of zinc phosphate.
The compound having an amino group may be carried inside the pores of the porous inorganic powder, or may be carried exposed on the outermost surface of the porous inorganic powder.
The loading amount of the compound having an amino group in the present invention is preferably 0.1 wt% to 30 wt% (preferably 0.2 wt% to 20 wt%) with respect to the weight of the porous inorganic powder. When the loading amount is smaller than 0.1 wt%, the improvement of the removal ability with respect to the aldehyde gas is not observed. When the loading amount is larger than 30 wt%, the compound having an amino group is detached and discolored, the transparency is impaired, and the compound having an amino group itself may cause a bad odor.

  The method for supporting the amino group-containing compound on the porous inorganic powder is not particularly limited. For example, a dry method in which a compound having an amino group is mixed with the porous inorganic powder, a porous inorganic powder and an amino group are mixed. Preferred examples include a wet method in which an aqueous solution of a compound having a group is mixed.

  As a dry method, the porous inorganic powder and the compound having an amino group are directly mixed in a known mixing apparatus such as a Henschel mixer, a vibration mill, a ball mill, a ribbon mixer, or a jet mill. At this time, in order to uniformly disperse the compound having an amino group in the porous inorganic powder, it is preferable to add a small amount of a dispersion medium (usually water or alcohols) and / or a known silane compound. A preferable temperature in mixing by this dry method is 0 ° C to 100 ° C, more preferably 5 ° C to 80 ° C.

  As a wet method, first, a compound having an amino group is dissolved in a solvent to prepare a solution. Next, after adding porous inorganic powder to this solution, it is stirred for 5 minutes to 12 hours, preferably for 10 minutes to 6 hours. The temperature at this time is 0 ° C to 100 ° C, preferably 4 ° C to 80 ° C. Furthermore, the target adsorbent can be obtained by washing the porous inorganic powder carrying the amino group-containing compound with water, etc., removing the compound having an excess amino group adhering to the surface, and drying. . The drying method at this time may be performed in air at 50 ° C. to 120 ° C., or may be performed by a freeze drying method or a vacuum drying method.

The average particle size of the adsorbent of the present invention is preferably 0.01 μm to 100 μm, more preferably 0.1 μm to 50 μm. By being in such a range, it exhibits excellent gas adsorbing ability and further excellent transparency. Moreover, when it uses for support bodies, such as a coating film and a fiber, if a particle diameter is such a range, the outstanding dispersibility can be shown.
Further, the specific surface area of the adsorbent of the present invention is preferably 10 m ² / g or more, more preferably 15 m ² / g or more. When the specific surface area is 10 m ² / g or more, the adsorption of harmful gas can proceed more efficiently.

The adsorbent of the present invention is a compound in which a compound having an amino group is supported on a porous inorganic powder mainly composed of zinc phosphate, and is a gas such as ammonia, hydrogen sulfide, formaldehyde, acetaldehyde, or other aldehyde-based gas. Excellent adsorption capacity.
The adsorbent of the present invention uses a porous inorganic powder mainly composed of zinc phosphate, and is excellent in anticorrosion performance.

In addition, when the adsorbent of the present invention is fixed to a support such as an organic binder, the compounds having amino groups are difficult to contact with each other, have excellent dispersibility, and suppress the formation of secondary particles composed of compounds having amino groups. In addition, the compound having an amino group and the support are hardly brought into contact with each other, and discoloration of the support can be suppressed.
Furthermore, when the adsorbent of the present invention is used by being applied to various members such as wood and metal together with a support such as an organic binder, the adsorbent of the present invention is excellent in transparency. Can be used.

The adsorbent of the present invention may be used alone when removing harmful gases, or may be used in combination with an antibacterial agent, a photocatalyst, another adsorbent and the like.
Antibacterial agents include, for example, silver, copper, zinc, lead, bismuth and the like, or inorganic antibacterial agents such as ions and complexes thereof, phenolic antibacterial agents such as phenol, resorcin, cresol, biosol, thymol, and β-naphthol. Imidazole antibacterial agents such as imidazole, benzimidazole and thiabendazole, biguanide antibacterial agents such as chlorhexidine hydrochloride, chlorhexidine gluconate, chlorhexidine acetate, polyhexamethylene biguanidine hydrochloride, 2,3,3-triiodoallyl alcohol, diiodomethyl- Examples thereof include iodo-based antibacterial agents such as p-trisulfone, and antibacterial agents derived from natural products such as allyl mustard oil, wasaolo, hinokitiol, and protamine.
Examples of the photocatalyst include titanium oxide, zinc oxide, zinc sulfide, tin oxide, tungsten oxide, and bismuth vanadate.
Other adsorbents include, for example, zirconium phosphate, aluminum phosphate, magnesium phosphate, magnesium aluminosilicate, titanium phosphate, zirconium hydroxide, bismuth hydroxide, iron oxide, titanium phosphate, potassium titanate, silica gel, Examples include activated alumina, diatomaceous earth, acid clay, zeolite, foamed vermiculite, activated carbon, bamboo charcoal, and charcoal.
Among these antibacterial agents, photocatalysts, and other adsorbents, one type may be used in combination, or two or more types may be combined or mixed and used together.
By using such an antibacterial agent, a photocatalyst, and other adsorbents in combination, in addition to the effects of the present invention, an antibacterial effect, a photocatalytic effect, and the like can be imparted, and the adsorption performance can be further improved.
Further, the method of using the harmful gas adsorbent of the present invention is not limited. For example, the powder may be retained in the atmosphere as it is to perform target harmful gas adsorption. Toxic gas adsorption may be performed, and it may be supported on a coating film, glass, wallpaper, curtain, shoji paper, various panels, boards, or the like.

  Examples and Comparative Examples are shown below to clarify the features of the present invention, but the present invention is not limited to these Examples.

(Measuring method)
1. The crystal structure of the porous inorganic powder was analyzed by an X-ray diffractometer (RINT-1100, manufactured by Rigaku Corporation).
2. The composition of the porous inorganic powder was analyzed using an elemental analysis (EDS) apparatus attached to an electron microscope (JSM-5310, manufactured by JEOL Ltd.).
3. The particle shape and particle diameter of the adsorbent were observed with an electron microscope (JSM-5310, manufactured by JEOL Ltd.).
4). The specific surface area of the adsorbent was measured by BET method with a dead volume measuring gas: helium and an adsorbing gas: nitrogen using a surface area measuring device P-700 type manufactured by Shibata Scientific Instruments Co., Ltd.
5. Evaluation test of formaldehyde removal ability After placing 0.01 g of adsorbent in a Tedlar bag having a volume of 1.0 L, 1.0 L of 3.0 ppm of formaldehyde gas was sealed, and the change in formaldehyde concentration was measured 10 minutes later. Measured with a detector tube.
6). Yellowing resistance test A water-based paint in which 100 parts by weight of an acrylic emulsion (solid content 50%), 50 parts by weight of titanium oxide, 3 parts by weight of a thickener, and 1 part by weight of an adsorbent were mixed with an aluminum plate (70 mm × 150 mm × 0. 8 mm) using a film applicator so that the coating thickness is 0.125 mm, and dried at a temperature of 23 ° C. and a relative humidity of 50% for 24 hours to obtain a test specimen. Then, the test body was put into the thermostat and left still at 50 degreeC for 2 weeks.
In the yellowing resistance test, a color difference meter (CM-3700d, manufactured by Minolta Co., Ltd.) was used to evaluate the color difference (Δb) before and after standing for 2 weeks.

Example 1
A mixed solution was prepared by mixing 1.0 L of a 0.3 mol / L zinc sulfate aqueous solution and 1.2 L of a 0.17 mol / L sodium dihydrogen phosphate aqueous solution. The pH of this mixed solution was 3.2.
While stirring this mixed solution at a speed of 500 rpm, a 20% aqueous sodium hydroxide solution is added dropwise to adjust the pH to 8.5, the powder is precipitated, washed with water and acetone, and then freeze-dried. A porous inorganic powder was obtained by drying.
It was confirmed that the obtained porous inorganic powder was a porous inorganic powder mainly composed of zinc phosphate represented by Zn ₃ (PO ₄ ) ₂ .4H ₂ O.
Next, 2.0 g of tetraethylenepentamine was added to a slurry prepared by suspending 38.5 g of the obtained porous inorganic powder in 1.0 L of ion exchange water, and the mixture was stirred for 1 hour. After stirring, it was filtered, washed with water, and dried at 60 ° C. to obtain an adsorbent in which tetraethylenepentamine was supported on porous inorganic powder mainly composed of zinc phosphate.
The adsorbent of Example 1 obtained by the above method had an average particle size of 0.58 μm. Moreover, when the specific surface area was measured by BET method, it turned out that it has a specific surface area of 57 m < ² > / g.
Moreover, as a result of measuring the formaldehyde adsorption ability of the adsorbent of Example 1, the formaldehyde removal rate after 10 minutes was 90%, and it was confirmed that the formaldehyde removal ability was excellent.
In the yellowing resistance test, the color difference (Δb) was 0.11.

(Example 2)
In Example 1, an adsorbent was obtained in the same manner as in Example 1 except that diethylenetriamine was used instead of tetraethylenepentamine.
The average particle diameter of the adsorbent obtained in Example 2 was 0.49 μm. Further, when the specific surface area was measured by the BET method, it was found to have a specific surface area of 31 m ² / g.
As a result of measuring the formaldehyde adsorption ability of the adsorbent obtained in Example 2, the formaldehyde removal rate after 10 minutes was 85%, and it was confirmed that the adsorbent had excellent formaldehyde removal ability.
In the yellowing resistance test, the color difference (Δb) was 0.13.

(Example 3)
In Example 1, an adsorbent was obtained in the same manner as in Example 1 except that N-β (aminoethyl) -γ-aminopropyltrimethoxysilane was used instead of tetraethylenepentamine.
The average particle diameter of the adsorbent obtained in Example 3 was 0.66 μm. Moreover, when the specific surface area was measured by BET method, it turned out that it has a specific surface area of 60 m < ² > / g.
As a result of measuring the formaldehyde adsorption ability of the adsorbent obtained in Example 3, the formaldehyde removal rate after 10 minutes was 82%, and it was confirmed that the adsorbent had excellent formaldehyde removal ability.
In the yellowing resistance test, the color difference (Δb) was 0.02.

Example 4
A mixed solution was prepared by mixing 1.0 L of a 0.3 mol / L zinc sulfate aqueous solution, 2.3 L of a 0.3 mol / L aqueous aluminum chloride solution and 3.8 L of a 0.2 mol / L aqueous sodium dihydrogen phosphate solution. . The pH of this mixed solution was 1.7.
While stirring this mixed solution at a speed of 500 rpm, a 20% aqueous sodium hydroxide solution is added dropwise to adjust the pH to 8.5, the powder is precipitated, washed with water and acetone, and then freeze-dried. A porous inorganic powder was obtained by drying.
It was confirmed that the obtained porous inorganic powder was a porous inorganic powder mainly composed of zinc phosphate / aluminum represented by Zn ₃ Al ₆ (PO ₄ ) ₈ · 12H ₂ O.
Next, 2.0 g of N-β (aminoethyl) -γ-aminopropyltrimethoxysilane was added to a slurry prepared by suspending 38.5 g of the obtained porous inorganic powder in 1.0 L of ion exchange water. Added and stirred for 1 hour. After stirring, filtering, washing with water, and drying at 60 ° C., N-β (aminoethyl) -γ-aminopropyltrimethoxysilane is added to the porous inorganic powder mainly composed of zinc phosphate / aluminum. A supported adsorbent was obtained.
The average particle diameter of the adsorbent obtained in Example 4 was 0.45 μm. Further, when the specific surface area was measured by the BET method, it was found to have a specific surface area of 77 m ² / g.
Moreover, as a result of measuring the formaldehyde adsorption ability of the adsorbent obtained in Example 4, the formaldehyde removal rate after 10 minutes was 75%, and it was confirmed that the adsorbent had excellent formaldehyde removal ability.
In the yellowing resistance test, the color difference (Δb) was 0.02.

(Example 5)
A mixed solution was prepared by mixing 1.0 L of a 0.4 mol / L zinc sulfate aqueous solution, 2.3 L of a 0.3 mol / L calcium nitrate aqueous solution and 3.8 L of a 0.2 mol / L sodium dihydrogen phosphate aqueous solution. . The pH of this mixed solution was 3.4.
While stirring this mixed solution at a speed of 500 rpm, a 20% aqueous sodium hydroxide solution is added dropwise to adjust the pH to 8.5, the powder is precipitated, washed with water and acetone, and then freeze-dried. A porous inorganic powder was obtained by drying.
The obtained porous inorganic powder was confirmed to be a porous inorganic powder mainly composed of zinc phosphate / calcium represented by Zn ₁ Ca ₂ (PO ₄ ) ₂ .4H ₂ O.
Next, 2.0 g of N-β (aminoethyl) -γ-aminopropyltrimethoxysilane was added to a slurry prepared by suspending 38.5 g of the obtained porous inorganic powder in 1.0 L of ion exchange water. Added and stirred for 1 hour. After stirring, filtering, washing with water, and drying at 60 ° C., N-β (aminoethyl) -γ-aminopropyltrimethoxysilane is added to the porous inorganic powder mainly composed of zinc phosphate / calcium. A supported adsorbent was obtained.
The average particle diameter of the adsorbent obtained in Example 5 was 0.50 μm. Moreover, when the specific surface area was measured by BET method, it turned out that it has a specific surface area of 73 m < ² > / g.
Moreover, as a result of measuring the formaldehyde adsorption ability of the adsorbent obtained in Example 5, the formaldehyde removal rate after 10 minutes was 37%, and it was confirmed that the adsorbent had good formaldehyde removal ability.
In the yellowing resistance test, the color difference (Δb) was 0.03.

(Comparative Example 1)
In Example 1, as a result of evaluating the formaldehyde removal ability using the porous inorganic powder (53 m ² / g), the formaldehyde removal rate after 10 minutes was 20%, and the formaldehyde removal ability was inferior.

Claims (4)

An adsorbent comprising a porous inorganic powder mainly composed of zinc phosphate represented by the following composition formula 1 and a compound having an amino group supported thereon.
(Composition Formula 1)
_{Zn k X l (PO 4)} m Y n · oH 2 O
(X is a p-valent metal ion (p is 2 or 3), Y is a q-valent anion (q is 1, 2 or 3), k, l, m, n are 2k + p × l− (3m + q × n) = Real number satisfying 0 (where k and m are positive real numbers, l and n are 0 or positive real numbers), o is a real number of 0 or more)   The adsorbent according to claim 1, wherein the compound having an amino group is supported at 0.1 to 30 wt% with respect to the porous inorganic powder.   The adsorbent according to any one of claims 1 and 2, wherein an average particle diameter is 0.01 to 100 µm. The adsorbent according to claim 1, wherein the specific surface area is 10 m ² / g or more.