KR20200053475A - Oxidation method of carbon monoxide, carbon monoxide oxidation device, air purifier, and gas mask - Google Patents

Abstract

As a method for oxidizing carbon monoxide, a step of oxidizing carbon monoxide gas in a mixed gas containing carbon monoxide gas and oxygen gas with oxygen gas in the mixed gas at a temperature of 100 ° C. or less in the presence of a catalyst, the mixed gas comprising The hydrogen chloride concentration is less than 1% by volume, and the catalyst is selected from the group consisting of a rutile crystal-type titanium oxide carrier and a ruthenium element-containing substance supported on the carrier, and the ruthenium element-containing substance is a metal ruthenium and ruthenium compound A method for oxidizing carbon monoxide, which is at least one kind, is provided.

Description

Oxidation method of carbon monoxide, carbon monoxide oxidation device, air purifier, and gas mask

The present invention relates to a method for oxidizing carbon monoxide, a carbon monoxide oxidation apparatus, an air purifier, and a gas mask.

Background Art Conventionally, a method of reducing carbon monoxide has been known by oxidizing carbon monoxide contained in exhaust gas or air of automobiles to form carbon dioxide. As a catalyst for oxidizing carbon monoxide, a catalyst composed of platinum and alumina is known. For example, Japanese Patent Application Laid-Open No. Hei 04-215845 (Patent Document 1), by oxidation reaction using a catalyst composed of platinum and alumina, 230 It has been described that 50% of carbon monoxide contained in the exhaust gas is oxidized to be carbon dioxide at ℃.

Japanese Laid-Open Patent Publication No. 04-215845

Recently, a method for oxidizing carbon monoxide at a lower temperature has been required.

An object of the present invention is to provide a method capable of oxidizing carbon monoxide even at a temperature of 100 ° C or less.

Another object of the present invention is to provide an apparatus capable of oxidizing carbon monoxide even at a temperature of 100 ° C. or less, an air purifier, and a gas mask.

The present invention provides the following.

[1] As a method for oxidizing carbon monoxide,

And a step of oxidizing carbon monoxide gas in the mixed gas containing carbon monoxide gas and oxygen gas with oxygen gas in the mixed gas at a temperature of 100 ° C. or less in the presence of a catalyst,

The mixed gas has a hydrogen chloride concentration of less than 1% by volume,

The catalyst contains a rutile crystalline titanium oxide carrier and a ruthenium element-containing material supported on the carrier,

The ruthenium element-containing material is at least one selected from the group consisting of metal ruthenium and ruthenium compounds, a method for oxidizing carbon monoxide.

[2] The method for oxidizing carbon monoxide according to [1], wherein the mixed gas has a relative humidity of 90% RH or less.

[3] The method for oxidizing carbon monoxide according to [1] or [2], wherein the mixed gas contains air.

[4] A carbon monoxide oxidation apparatus comprising a carbon monoxide oxidation catalyst,

The carbon monoxide oxidation catalyst contains a carrier containing rutile crystalline titanium oxide and a ruthenium element-containing material supported on the carrier,

The ruthenium element-containing material is at least one selected from the group consisting of metal ruthenium and ruthenium compounds, carbon monoxide oxidation apparatus.

[5] The carbon monoxide oxidation apparatus according to [4], which is an air purifier.

[6] A gas mask comprising a carbon monoxide oxidation catalyst,

The carbon monoxide oxidation catalyst contains a carrier containing rutile crystalline titanium oxide and a ruthenium element-containing material supported on the carrier,

The ruthenium element-containing material is at least one selected from the group consisting of metal ruthenium and ruthenium compounds, gas mask.

According to the present invention, it is possible to provide a method capable of oxidizing carbon monoxide even at a temperature of 100 ° C or less.

According to the present invention, an apparatus capable of oxidizing carbon monoxide, an air purifier, and a gas mask can be provided even at a temperature of 100 ° C. or less.

<Carbon monoxide oxidation catalyst>

The carbon monoxide oxidation catalyst (hereinafter also simply referred to as "carbon monoxide oxidation catalyst") used in the carbon monoxide oxidation method and carbon monoxide oxidation apparatus according to the present invention will be described.

The carbon monoxide oxidation catalyst contains a carrier containing rutile crystalline titanium oxide and a ruthenium element-containing substance supported thereon.

Examples of the ruthenium element-containing substance include at least one selected from the group consisting of metal ruthenium and ruthenium compounds.

The carbon monoxide oxidation catalyst may contain two or more ruthenium element-containing substances.

The carbon monoxide oxidation catalyst may contain both metal ruthenium and ruthenium compounds.

(1) Ruthenium compounds

The ruthenium compound is a compound containing a ruthenium element.

Examples of ruthenium compounds include ruthenium oxide, ruthenium chloride, chlororuthenate, chlororuthenium hydrate, ruthenium acid salt, rutheniumoxychloride, rutheniumoxychloride salt, rutheniumammine complex, rutheniumammine complex chloride, ruthenium And bromide, ruthenium carbonyl complex, ruthenium organic acid salt, ruthenium nitrosyl complex, and ruthenium phosphine complex.

RuO ₂ and RuO ₄ are mentioned as ruthenium oxide.

Examples of ruthenium chloride include RuCl ₃ and RuCl ₃ hydrate.

Examples of the chlororuthenate salt include K ₃ RuCl ₆ , [RuCl ₆ ] ^3- , and K ₂ RuCl ₆ .

Examples of the chlororuthenate hydrate include [RuCl ₅ (H ₂ O) ₄ ] ^2- , [RuCl ₂ (H ₂ O) ₄ ] ⁺ and the like.

Examples of salts of ruthenic acid include K ₂ RuO ₄ and the like.

Examples of ruthenium oxychloride include Ru ₂ OCl ₄ , Ru ₂ OCl ₅ , and Ru ₂ OCl ₆ .

Examples of salts of ruthenium oxychloride include K ₂ Ru ₂ OCl ₁₀ and Cs ₂ Ru ₂ OCl ₄ .

Examples of the ruthenium-amine complex include [Ru (NH ₃ ) ₆ ] ²⁺ , [Ru (NH ₃ ) ₆ ] ³⁺ , [Ru (NH ₃ ) ₅ H ₂ O] ²⁺ and the like.

As the chloride of the ruthenium ammine complex, [Ru (NH ₃ ) ₅ Cl] ²⁺ , [Ru (NH ₃ ) ₆ ㆍ Cl ₂ , [Ru (NH ₃ ) ₆ 〕 Cl ₃ , [Ru (NH ₃ ) ₆ 〔Br ₃ etc. are mentioned.

Examples of ruthenium bromide include RuBr ₃ and RuBr ₃ hydrate.

Examples of the ruthenium carbonyl complex include Ru (CO) ₅ and Ru ₃ (CO) ₁₂ .

Examples of the ruthenium organic acid salt include [Ru ₃ O (OCOCH ₃ ) ₆ (H ₂ O) ₃ ] OCOCH ₃ hydrate, Ru ₂ (RCOO) ₄ Cl (R represents an alkyl group having 1 to 3 carbon atoms), and the like. You can.

As the ruthenium nitrosyl complex, K ₂ [RuCl ₅ (NO)], [Ru (NH ₃ ) ₅ (NO)] Cl ₃ , [Ru (OH) (NH ₃ ) ₄ (NO)] (NO ₃ ) ₂ , Ru (NO) (NO ₃ ) ₃ and the like.

It is preferable that the ruthenium compound is a ruthenium oxide, ruthenium chloride, ruthenium bromide, a salt of ruthenic acid, and a ruthenium nitrosyl complex from the viewpoint of catalytic activity and availability.

The carbon monoxide oxidation catalyst may contain two or more types of ruthenium compounds.

The content of the ruthenium element-containing substance in the carbon monoxide oxidation catalyst is preferably 0.1 wt% or more and 20 wt% or less, more preferably 0.5 wt% or more and 10 wt% or less, based on the metal ruthenium, from the viewpoint of catalytic activity, More preferably, it is 1.0 weight% or more and 5 weight% or less.

The content of the ruthenium element-containing material is, from the viewpoint of catalytic activity, the total amount of the ruthenium element-containing material and the carrier is 100% by weight, preferably 0.1% by weight or more and 20% by weight or less, more preferably on a metal ruthenium basis, more preferably Is 0.5% by weight or more and 10% by weight or less, and more preferably 1.0% by weight or more and 5% by weight or less.

(2) Carrier containing rutile crystalline titanium oxide

The carrier contained in the carbon monoxide oxidation catalyst contains rutile crystalline titanium oxide (titanium (IV) oxide). The carrier may contain anatase crystalline titanium oxide (titanium (IV) oxide) in addition to the rutile crystalline titanium oxide.

From the viewpoint of catalytic activity, the content of the rutile crystalline titanium oxide in the titanium oxide contained in the carrier is preferably 20% by weight or more, with the total amount of titanium oxide contained in the carrier being 100% by weight, more preferably It is 30% by weight or more, more preferably 50% by weight or more, still more preferably 80% by weight or more, and particularly preferably 90% by weight or more.

The carrier may contain substances other than titanium oxide. Examples of substances other than titanium oxide include metal oxides other than titanium oxide.

The carrier may contain a complex oxide of titanium oxide and other metal oxides in addition to the rutile crystalline titanium oxide.

The carrier may be a mixture of titanium oxide and other metal oxides.

Examples of metal oxides other than titanium oxide include alumina, silica, and zirconium oxide.

When the carrier contains a substance other than titanium oxide (for example, a metal oxide other than titanium oxide), the content of titanium oxide in the carrier is usually 10% by weight or more, preferably 30% by weight or more, and more preferably It is 40% by weight or more, and more preferably 50% by weight or more.

As a method for preparing the rutile crystal-type titanium oxide, a known method can be adopted, and the following method can be mentioned, for example.

[A] After the titanium tetrachloride was dissolved in ice-cold water dropwise and dissolved, it was neutralized with an aqueous ammonia solution at a temperature of 20 ° C. or higher to produce titanium hydroxide (orthotitanic acid), followed by washing the produced precipitate with water to remove chlorine ions, 600 Method for firing at a temperature above ℃ (catalyst preparation chemistry, 1989, p. 211, Kodansha)

[B] A method of preparing a reaction gas by passing an oxygen-nitrogen mixed gas through a titanium tetrachloride evaporator, and introducing it into a reactor to oxidize the reaction gas at 900 ° C. or higher (Catalyst Preparation Chemistry, 1989, p. 89, Kodansha ).

[C] Hydrolysis of titanium tetrachloride in the presence of ammonium sulfate, followed by calcination (eg, Catalytic Engineering Lecture 10 Elemental Catalysts Handbook, 1978, p. 254, Chijinshokan).

[D] Method for firing anatase crystalline titanium oxide (for example, metal oxide and complex oxide, 1980, p. 107, Kodansha).

[E] A method of heating and hydrolyzing a titanium chloride aqueous solution.

[F] A method of mixing an aqueous solution of a titanium compound such as titanium sulfate or titanium chloride with a rutile crystalline titanium oxide powder, followed by heat hydrolysis or alkali hydrolysis, followed by calcination at a temperature of about 500 ° C.

A commercially available product may be used for the rutile crystalline titanium oxide.

The carrier can be obtained by molding rutile crystalline titanium oxide into a desired shape. When the carrier contains a metal oxide other than rutile crystal type titanium oxide, it can be obtained by molding a mixture of rutile crystal type titanium oxide and other metal oxides into a desired shape. The obtained molded product may be subjected to operations such as crushing, grinding, and classification.

It can be confirmed by X-ray diffraction analysis that the carrier contains rutile crystalline titanium oxide. The X-ray source is not particularly limited, and examples thereof include Kα rays of copper.

When a copper Kα ray is used as the X-ray source, it can be confirmed by the presence or absence of a diffraction peak of 2θ = 27.5 degrees on the (110) plane that the carrier contains a rutile crystalline titanium oxide. When the carrier contains anatase crystalline titanium oxide, a diffraction peak of 2θ = 25.3 degrees on the (101) plane is observed.

Therefore, when the copper Kα ray is used as the X-ray source, the content of rutile crystals and anatase crystals is obtained from the intensity of the 2θ = 27.5 degree diffraction peak on the (110) plane and the intensity of the diffraction peak of 2θ = 25.3 degrees on the (101) plane. The ratio (weight ratio) can be obtained.

The carrier may have at least a diffraction peak derived from a rutile crystal and an diffraction peak derived from an anatase crystal in an X-ray diffraction analysis using a copper Kα ray.

The rutile crystalline titanium oxide or carrier constituting the carrier may be surface-treated for the purpose of preventing the deterioration of the catalyst performance by adsorbing the substance causing the catalyst poisoning to the catalyst surface.

The substance used for the surface treatment may be an inorganic substance or an organic substance.

Examples of inorganic materials used for surface treatment include metal oxides and metal hydroxides. Examples of the metal constituting the metal oxide and the metal hydroxide include aluminum, silicon, zinc, titanium, zirconium, iron, cerium and tin.

As for the inorganic substance used for surface treatment, only 1 type may be used and 2 or more types may be used together.

The method for preparing the metal oxide and metal hydroxide is not particularly limited, and can be prepared with a corresponding metal salt. The type of the metal salt is not particularly limited and is appropriately selected depending on the preparation method.

As an organic substance used for surface treatment, a fatty acid, a silylating agent, etc. are mentioned, for example.

Examples of the fatty acids include stearic acid, oleic acid, isostearic acid, myristic acid, and the like.

Examples of the silylating agent include organic silane, organic silylamine, organic silylamide and derivatives thereof, and organic silazane.

Examples of the organic silane include chlorotrimethylsilane, dichlorodimethylsilane, chlorobromodimethylsilane, nitrotrimethylsilane, chlorotriethylsilane, iodinedimethylbutylsilane, chlorodimethylphenylsilane, chlorodimethylsilane, and dimethyln-propyl Chlorosilane, dimethylisopropylchlorosilane, tert-butyldimethylchlorosilane, tripropylchlorosilane, dimethyloctylchlorosilane, tributylchlorosilane, trihexylchlorosilane, dimethylethylchlorosilane, dimethyloctadecylchlorosilane, n-butyl Dimethylchlorosilane, bromomethyldimethylchlorosilane, chloromethyldimethylchlorosilane, 3-chloropropyldimethylchlorosilane, dimethoxymethylchlorosilane, methylphenylchlorosilane, triethoxychlorosilane, dimethylphenylchlorosilane, methylphenylvinylchlorosilane , Benzyldimethylchlorosilane, diphenylchlorosilane, diphenylmethylchlorosilane , Diphenylvinylchlorosilane, tribenzylchlorosilane, 3-cyanopropyldimethylchlorosilane, and the like.

Organic silylamines include, for example, N-trimethylsilylimidazole, N-tert-butyldimethylsilylimidazole, N-dimethylethylsilylimidazole, N-dimethyln-propylsilylimidazole, N -Dimethylisopropylsilylimidazole, N-trimethylsilyldimethylamine, N-trimethylsilyldiethylamine, N-trimethylsilylpyrrole, N-trimethylsilylpyrrolidine, N-trimethylsilylpiperidine, 1-cyano And ethyl (diethylamino) dimethylsilane and pentafluorophenyldimethylsilylamine.

Organic silylamides and derivatives include, for example, N, O-bistrimethylsilylacetamide, N, O-bistrimethylsilyltrifluoroacetamide, N-trimethylsilylacetamide, N-methyl-N-trimethylsilyl Acetamide, N-methyl-N-trimethylsilyl trifluoroacetamide, N-methyl-N-trimethylsilylheptafluorobutylamide, N- (tert-butyldimethylsilyl) -N-trifluoroacetamide, N And O-bis (diethylhydrosilyl) trifluoroacetamide.

Examples of the organic silazane include hexamethyldisilazane, heptamethyldisilazane, 1,1,3,3-tetramethyldisilazane, 1,3-bis (chloromethyl) tetramethyldisilazane. , 1,3-divinyl-1,1,3,3-tetramethyldisilazane, 1,3-diphenyltetramethyldisilazane, and the like.

Other silylating agents include, for example, N-methoxy-N, O-bistrimethylsilyltrifluoroacetamide, N-methoxy-N, O-bistrimethylsilylcarbamate, N, O-bis And trimethylsilyl sulfamate, trimethylsilyl trifluoromethanesulfonate, and N, N'-bistrimethylsilylurea.

As for the organic substance used for surface treatment, only 1 type may be used and 2 or more types may be used together.

The silylating agent is preferably an organic silazane, more preferably hexamethyldisilazane, because it is easy to achieve the above object.

(3) Other components that may be included in the carbon monoxide oxidation catalyst

A metal element other than ruthenium may be supported on the carrier of the carbon monoxide oxidation catalyst.

As a metal element other than ruthenium, transition metals, such as silver and copper, and typical metals, such as zinc and tin, are mentioned, for example.

Metal elements other than ruthenium may be supported in a reduced state (as a single metal) in a metal, may be supported as a metal oxide, or may be supported as a complex oxide containing a plurality of metal elements.

Further, metal elements other than ruthenium may form an alloy with ruthenium supported on the carrier, or may form a complex oxide containing ruthenium.

In the use of the carbon monoxide oxidation catalyst, the carbon monoxide oxidation catalyst may be diluted with an inert substance.

(4) Method for preparing carbon monoxide oxidation catalyst

The carbon monoxide oxidation catalyst can be prepared by supporting a ruthenium element-containing substance on a carrier using a method such as an impregnation method, an ion exchange method, or a coprecipitation method. The solvent used in the impregnation method is not particularly limited, but water, ethanol, or the like can be used.

Examples of the shape of the catalyst include a spherical granular shape, a columnar pellet shape, a ring shape, a honeycomb shape, a monolith shape, a collate shape, or granules or fine particles of a suitable size pulverized and classified after molding the carrier.

In the case of spherical granules, columnar pellets, and ring shapes, from the viewpoint of catalytic activity, the catalyst diameter is preferably 10 mm or less. In addition, the catalyst diameter referred to herein means a diameter of a sphere in a spherical granular shape, a diameter of a cross section in a cylindrical pellet shape, and a maximum diameter of a cross section in other shapes.

In the case of a honeycomb shape, a monolith shape, or a colgate shape, the opening diameter is usually 20 mm or less.

The carbon monoxide oxidation catalyst may be heat treated before use after preparation. Thereby, the catalyst activity may be increased or the catalyst life may be increased.

Although the heat treatment temperature is not particularly limited, it is usually 100 ° C or higher and 500 ° C or lower.

The heat treatment can be carried out in an inert gas such as nitrogen, argon or helium, in air, or in a gas containing carbon monoxide or hydrogen.

<Oxidation method of carbon monoxide>

The carbon monoxide oxidation method according to the present invention is a method using the carbon monoxide oxidation catalyst, wherein carbon monoxide gas in a mixed gas containing carbon monoxide gas and oxygen gas at a temperature of 100 ° C. or lower in the presence of a catalyst is oxygen gas in the mixed gas. And oxidizing.

According to the oxidation method of carbon monoxide according to the present invention, since the carbon monoxide oxidation catalyst is used, carbon monoxide can be oxidized by catalytic reaction even at a reaction temperature of 100 ° C or lower. Carbon dioxide is produced by oxidation of carbon monoxide.

The oxidizing step can be carried out, for example, by supplying the mixed gas containing carbon monoxide gas and oxygen gas to a receiving portion containing a carbon monoxide oxidation catalyst. In this case, carbon monoxide gas in the mixed gas is oxidized by oxygen gas in the mixed gas.

The accommodation portion may be a part of a device, a tool, or the like.

Before the oxidizing step, a step of preparing a mixed gas containing a carbon monoxide gas and an oxygen gas by mixing gas or chemical reaction may be provided.

The mixed gas may be, for example, a gas containing air, or may be composed of air.

The oxygen gas contained in the mixed gas may be obtained by a conventional industrial method such as an air pressure swing method or deep-separation.

The mixed gas has a hydrogen chloride concentration of less than 1 volume%, preferably 0.5 volume% or less, more preferably 0.1 volume% or less, and even more preferably 0 or substantially 0 volume% (below the detection limit). .

When the concentration of hydrogen chloride is less than 1% by volume, the carbon monoxide gas in the mixed gas can be oxidized using the carbon monoxide oxidation catalyst even at a temperature of 100 ° C. or less. When the hydrogen chloride concentration is 1% by volume or more, the oxidation reaction tends to not proceed sufficiently, and the catalyst life tends to decrease easily.

The concentration of the carbon monoxide gas in the mixed gas may depend on the application to which the carbon monoxide oxidation catalyst is applied, for example, 0.0001% by volume or more and 10% by volume or less, preferably 0.0005% by volume or more and 5% by volume or less, more preferably It is 0.001% by volume or more and 3% by volume or less.

The concentration of the oxygen gas in the mixed gas is a concentration such that the amount of oxygen gas contained is equal to or greater than the theoretical amount necessary for oxidizing carbon monoxide, for example, 0.1 volume% or more and 30 volume% or less, and 0.1 volume% or more and 21 volumes % Or less. When the mixed gas is air containing carbon monoxide, the concentration of oxygen gas in the mixed gas is usually 21% by volume or its vicinity.

The mixed gas may contain components other than carbon monoxide gas and oxygen gas.

Other components include water vapor, nitrogen, carbon dioxide, helium, aldehydes, fatty acids, sulfur compounds, and nitrogen compounds. The mixed gas may contain only one type of other components, or may contain two or more types.

When another component is contained in the mixed gas supplied to the carbon monoxide oxidation catalyst, other components may be oxidized in the oxidation step.

The mixed gas may contain water vapor, as described above. However, the relative humidity of the mixed gas is preferably 90% RH or less, more preferably 60% RH or less, even more preferably 30% RH or less, even more preferably 10% RH or less, particularly It is preferably 5% RH or less, and most preferably 0% RH.

The smaller the moisture content of the mixed gas supplied to the carbon monoxide oxidation catalyst, the higher the catalytic activity and tends to increase the conversion of carbon monoxide to carbon dioxide.

In order to reduce the moisture content of the mixed gas supplied to the carbon monoxide oxidation catalyst, in an apparatus or the like including a carbon monoxide oxidation catalyst, means for performing dehydration treatment on the mixed gas may be combined. Examples of the dehydration treatment include a dehydration treatment using molecular sieves, zeolites, silica gel, and the like.

Examples of the aldehyde include formaldehyde, acetaldehyde, and propionaldehyde.

Examples of the fatty acid include formic acid, acetic acid, and propionic acid.

Examples of the sulfur compound include methyl mercaptan, sulfur dioxide, hydrogen sulfide, carbon disulfide, and carbonyl sulfide.

Examples of the nitrogen compound include trimethylamine, triethylamine, ethylamine, and ammonia.

The oxidizing step can be carried out by bringing the carbon monoxide oxidation catalyst into contact with carbon monoxide gas and oxygen gas in the mixed gas, and oxidizing the carbon monoxide gas in the mixed gas with oxygen gas in the mixed gas. The said contact can be performed by introducing a mixed gas into the accommodation part in which the carbon monoxide oxidation catalyst is accommodated. The mixed gas may be introduced into the accommodation portion in which the carbon monoxide oxidation catalyst is accommodated by application of pressure, or may be introduced into the accommodation portion by intake.

In one embodiment, the method of the oxidation reaction in the oxidation step is a fixed bed gas phase flow reaction method, a fluidized bed gas phase flow reaction method, or a rotor type mobile phase reaction method.

In another embodiment, the method of the oxidation reaction in the oxidizing step is a method of performing the contact by standing a carbon monoxide oxidation catalyst in the mixed gas.

The reaction temperature in the oxidation step is usually 100 ° C or lower. The reaction temperature is preferably 0 ° C or higher, more preferably 10 ° C or higher, and even more preferably 20 ° C or higher from the viewpoint of catalytic activity. The reaction temperature is preferably 80 ° C. or lower, more preferably 60 ° C. or lower, more preferably 50 ° C. or lower, even more preferably 40 ° C. or lower, particularly preferably from the viewpoint of durability of the catalyst Is 30 ° C or less.

In the method for oxidizing carbon monoxide and the carbon monoxide oxidizing apparatus according to the present invention, the amount of the carbon monoxide oxidation catalyst used is usually supplied in the standard state (0 ° C., 0.1 MPa) per 1 liter of the carbon monoxide oxidation catalyst, in the supply of the mixed gas The speed (GHSV) is an amount of 10 to 500000 h ^-1 .

In the oxidation method for carbon monoxide and the carbon monoxide oxidation apparatus according to the present invention, the gas linear velocity based on the air column of the mixed gas is usually 1 m / s or more and 40 m / s or less. The gas linear velocity based on the air column means the ratio of the total amount of the feed rate in the standard state (0 ° C, 0.1 MPa) of all gas components supplied to the receiving section to the cross-sectional area of the receiving section such as a reactor. The reaction pressure is usually 0.1 MPa or more and 5 MPa or less.

<Carbon monoxide oxidation device and gas mask>

The carbon monoxide oxidation apparatus according to the present invention includes the carbon monoxide oxidation catalyst according to the present invention.

As a carbon monoxide oxidation apparatus, For example, the carbon monoxide oxidation equipment which comprises facilities of a factory, such as a chemical factory, or a part thereof; And machines or devices having a function of oxidizing carbon monoxide.

According to the carbon monoxide oxidation apparatus according to the present invention, it is possible to obtain a gas whose carbon monoxide concentration is reduced or does not contain carbon monoxide. Alternatively, according to the carbon monoxide oxidation apparatus according to the present invention, the carbon monoxide concentration in the environment can be reduced, or an environment that does not contain carbon monoxide can be obtained.

For example, in the carbon monoxide oxidizing device formed in a factory facility, the method of the oxidation reaction in the oxidation step is preferably a fixed bed gas phase flow reaction method, a fluidized bed gas phase flow reaction method, or a rotor type mobile phase reaction method. .

In the carbon monoxide oxidizing device formed in a factory facility, the accommodation portion in which the above-described carbon monoxide oxidation catalyst is accommodated may be a reactor, a reaction tower (catalyst tower) or the like.

In the carbon monoxide oxidizing device formed in a factory facility, the mixed gas introduced into the accommodating portion may be a gas produced in a factory or the like.

In order to reduce the water content of the mixed gas supplied to the accommodating portion in which the carbon monoxide oxidation catalyst is accommodated, a facility for dehydrating the mixed gas may be provided on the upstream side of the accommodating portion.

Another example of the carbon monoxide oxidation apparatus is an air cleaner.

In the air purifier, the gas supplied to the accommodating portion in which the carbon monoxide oxidation catalyst is accommodated is usually a mixed gas composed of air, but is not limited thereto.

In the air purifier, the concentration of the carbon monoxide gas in the mixed gas supplied to the accommodating portion in which the carbon monoxide oxidation catalyst is accommodated may be, for example, 0.001% by volume or more and 0.1% by volume or less. It is preferable that the concentration of the oxygen gas of this mixed gas is 21 volume% or the vicinity thereof.

In order to reduce the moisture content of the mixed gas supplied to the receiving portion in which the carbon monoxide oxidation catalyst is accommodated, an apparatus portion for performing dehydration treatment on the mixed gas may be formed on the upstream side of the receiving portion.

Another example of the carbon monoxide oxidizing device is an encapsulated gas regeneration device for a carbon dioxide gas laser.

In the carbon dioxide gas laser encapsulated gas regeneration device, the mixed gas supplied to the accommodating portion in which the carbon monoxide oxidation catalyst is accommodated is the encapsulated gas of the carbon dioxide gas laser. The concentration of oxygen in the sealed gas is preferably 0.1% by volume or more and 1.0% by volume or less, and the concentration of carbon monoxide is preferably 0.1% by volume or more and 2% by volume or less. Moreover, this sealed gas usually contains carbon dioxide further. The concentration of carbon dioxide in the sealing gas is preferably 5% by volume or more and 20% by volume or less.

In order to reduce the moisture content of the mixed gas supplied to the receiving portion in which the carbon monoxide oxidation catalyst is accommodated, an apparatus portion for performing dehydration treatment on the mixed gas may be formed on the upstream side of the receiving portion.

The gas mask according to the present invention includes the carbon monoxide oxidation catalyst.

By wearing this gas mask, suction of carbon monoxide can be prevented.

The carbon monoxide oxidation catalyst may be applied to devices other than the devices exemplified above, and devices and articles other than gas masks.

Example

For the following examples and comparative examples, various measurements were followed.

(A) Loading rate of ruthenium element-containing substances

The loading rate of the ruthenium element-containing material means the content (wt%) of the ruthenium element-containing material contained in 100% by weight of the catalyst.

The carrying ratio of the ruthenium element-containing substance was calculated according to the following formula.

Supporting rate of ruthenium element-containing material (% by weight) = 100 × 중량 (weight of catalyst) － (weight of carrier)｝ / (weight of catalyst)

[B] Ruthenium content in catalyst

The ruthenium content in the catalyst was calculated according to the following formula.

Ruthenium content in catalyst (wt%) = (support ratio obtained in [a] above) × (atomic amount of ruthenium 101.07) / (molar mass of ruthenium oxide 133.07)

[C] Contents of rutile crystal form titanium oxide (IV) contained in the carrier and anatase crystal form titanium oxide (IV) content

The carrier containing titanium oxide was subjected to X-ray diffraction analysis under the following conditions.

(Conditions of X-ray diffraction analysis)

Apparatus: "Rotor Flex RU200B" manufactured by Rigaku Corporation

X-ray source: Kα ray of copper

X-ray output: 40 ㎸-40 ㎃

Dissipation slit: 1 °

Scattering slit: 1 °

Light receiving slit: 0.15 mm

Scanning speed: 1 ° / min

Scanning range: 5.0 to 75.0 °

The weight ratio of the rutile crystal and the anatase crystal in titanium oxide contained in the carrier is determined by the following formula.

Weight ratio of rutile crystal and anatase crystal = 2θ on the (110) plane = intensity of the diffraction peak at 27.5 degrees / intensity of the diffraction peak at 2101 = 25.3 degrees on the (101) plane

In any of the catalysts prepared in the examples below, the titanium oxide contained in the carrier was composed of rutile crystals and anatase crystals. Therefore, the content rate of the rutile crystal in the titanium oxide contained in the carrier is obtained by the following formula when the total titanium oxide contained in the carrier is 100% by weight.

Content ratio (% by weight) of rutile crystals in titanium oxide contained in the carrier = 100 × 2 2θ = 27.5 degrees of intensity on the (110) plane｝ / ｛2θ = 27.5 degrees on the (110) plane = intensity of the diffraction peak of 27.5 degrees + ( 101) 2θ = 25.3 degrees of intensity of the diffraction peak of the surface

The content of the anatase crystals in the titanium oxide contained in the carrier is determined by the following formula when the total titanium oxide contained in the carrier is 100% by weight.

Content of anatase crystals in the titanium oxide contained in the carrier (% by weight) = 100 × 2 2θ on the (101) plane = intensity of the diffraction peak of 25.3 degrees｝ / ｛2θ on the (110) plane = intensity of the diffraction peak of 27.5 degrees + ( 101) 2θ = 25.3 degrees of intensity of the diffraction peak of the surface

<Example 1>

(1) Preparation of catalyst

50 parts by weight of rutile crystalline titanium oxide ("STR-60R" manufactured by Sakai Chemical Industry Co., Ltd., content of rutile crystalline form: 100% by weight) and 50 parts by weight of α-alumina ["AES-12" by Sumitomo Chemical Co., Ltd.] Mixed. Subsequently, with respect to 100 parts by weight of the mixture, titanium oxide sol ["CSB" manufactured by Sakai Chemical Industries, Ltd., titanium oxide content in titanium oxide: 39% by weight, anatase crystal form content of titanium oxide: 100% by weight] 12.8 weight The part diluted with 29 parts by weight of pure water was added and kneaded.

The obtained kneaded product was extruded into a cylindrical shape having a diameter of 1.5 mmφ, dried, and then crushed to a length of about 2 to 4 mm.

The obtained molded body was fired in air at 650 to 680 ° C. for 3 hours to obtain a carrier made of a mixture of titanium oxide and α-alumina (content of titanium oxide in carrier: 55% by weight).

The carrier was impregnated with an aqueous solution of commercially available ruthenium chloride hydrate (RuCl ₃ hydrate), and then dried. Thereafter, the catalyst (1) was obtained by firing in air at 250 ° C for 2 hours. The catalyst (1) contains ruthenium oxide (RuO ₂ ) as a ruthenium element-containing substance supported on a carrier. In the catalyst (1), the loading rate of the ruthenium element-containing substance was 4% by weight.

In accordance with the above, the ruthenium content (Ru content) in the catalyst (1), the content of the rutile crystal in the titanium oxide contained in the carrier of the catalyst (1), and the content of the anatase crystal were determined. Table 1 shows the results.

(2) Oxidation reaction of carbon monoxide

6.0 g of the obtained catalyst (1) was charged into a glass tubular reactor having an inner diameter of 16 mm. Carbon monoxide, a mixed gas prepared by mixing oxygen and nitrogen: the (composition of carbon monoxide 600 ppm, molecular oxygen (oxygen gas), 21% by volume, nitrogen balance and a relative humidity of 0% RH, the hydrogen chloride concentration of 0 vol.%) Supply speed 1600 h ^{- It} was supplied into the reactor at ¹ and reacted at 25 ° C.

The outlet gas (gas after reaction) 1 hour after the start of the reaction was sampled, and the carbon monoxide and carbon dioxide concentrations were analyzed by a gas detector (manufactured by Gastech Co., Ltd.). Based on the following formula, the conversion rate of carbon monoxide (%) was determined. Table 1 shows the results.

Conversion rate (%) = 100 × (concentration of carbon dioxide in the outlet gas) / (concentration of carbon monoxide in the mixed gas)

<Example 2>

(1) Preparation of catalyst

100 parts by weight of titanium oxide of rutile crystal form ("F1-R" manufactured by Showa Titanium, content of rutile crystal form: 93 wt%), and titanium oxide ["CSB" manufactured by Sakai Chemical Industries, Ltd. in titanium oxide Titanium oxide content: 39% by weight, anatase crystal form content of titanium oxide: 100% by weight] 12.8 parts by weight was diluted with 29 parts by weight of pure water, and kneaded.

The obtained kneaded product was extruded into a cylindrical shape having a diameter of 3.0 mmφ, dried, and then crushed to a length of about 3 to 5 mm.

The obtained molded body was fired in air at 600 ° C for 3 hours to obtain a carrier made of titanium oxide (content of titanium oxide in the carrier: 100% by weight).

The carrier was impregnated with an aqueous solution of commercially available ruthenium chloride hydrate (RuCl ₃ hydrate), and then dried. Thereafter, the catalyst (2) was obtained by firing in air at 250 ° C for 2 hours. The catalyst 2 contains ruthenium oxide (RuO ₂ ) as a ruthenium element-containing substance supported on a carrier. In the catalyst (2), the loading rate of the ruthenium element-containing substance was 4% by weight.

In accordance with the above, the ruthenium content (Ru content) in the catalyst (2), the content of the rutile crystal in the titanium oxide contained in the carrier of the catalyst (2), and the content of the anatase crystal were determined. Table 1 shows the results.

(2) Oxidation reaction of carbon monoxide

Except that the ruthenium oxide 2 supported on the reactor was charged, the oxidation reaction of carbon monoxide was carried out in the same manner as in Example 2 (2) to obtain the conversion rate (%) of carbon monoxide. Table 1 shows the results.

<Example 3>

(1) Preparation of catalyst

According to (1) of Example 1, the catalyst (1) was obtained.

(2) Oxidation reaction of carbon monoxide

6.0 g of the catalyst (1) was charged into a glass tubular reactor having an inner diameter of 16 mm. Supply rate of raw material gas prepared by mixing carbon monoxide, oxygen, nitrogen, and water (composition: carbon monoxide 600 ppm, molecular oxygen (oxygen gas) 21 vol%, nitrogen balance, relative humidity 30% RH, hydrogen chloride concentration 0 vol%) It was supplied into the reactor at 1600 h ^-1 and reacted at 25 ° C.

The outlet gas (gas after reaction) was sampled after 1 hour from the start of the reaction, and the carbon monoxide and carbon dioxide concentrations were analyzed with a gas detection tube (manufactured by Gastech Co., Ltd.), and the same method as in Example 1 (2) was used for carbon monoxide. The conversion rate (%) was determined. Table 1 shows the results.

<Example 4>

(1) Preparation of catalyst

According to (1) of Example 1, the catalyst (1) was obtained.

(2) Oxidation reaction of carbon monoxide

6.0 g of the catalyst (1) was charged into a glass tubular reactor having an inner diameter of 16 mm. Supply rate of raw material gas prepared by mixing carbon monoxide, oxygen, nitrogen, and water (composition: carbon monoxide 600 ppm, molecular oxygen (oxygen gas) 21 volume%, nitrogen balance, relative humidity 60% RH, hydrogen chloride concentration 0 volume%) It was supplied into the reactor at 1600 h ^-1 and reacted at 25 ° C.

The outlet gas (gas after reaction) was sampled after 1 hour from the start of the reaction, and the carbon monoxide and carbon dioxide concentrations were analyzed with a gas detection tube (manufactured by Gastech Co., Ltd.), and the same method as in Example 1 (2) was used for carbon monoxide. The conversion rate (%) was determined. Table 1 shows the results.

<Comparative Example 1>

(1) Preparation of catalyst

γ-alumina [Strem Chemicals, Inc. Preparation] was impregnated with a commercially available aqueous solution of chloroplatinic acid hydrate, and then dried. Thereafter, by firing in air at 250 ° C. for 2 hours, platinum alumina formed by supporting platinum on the γ-alumina carrier at a loading ratio of 3% by weight was obtained. The platinum content in this catalyst is 3% by weight.

(2) Oxidation reaction of carbon monoxide

A carbon monoxide oxidation reaction was conducted in the same manner as in Example 2 (2), except that the reactor was charged with the obtained platinum alumina, and the conversion rate (%) of carbon monoxide was obtained. Table 1 shows the results.

Claims (6)

As a method for oxidizing carbon monoxide,
And a step of oxidizing carbon monoxide gas in a mixed gas containing carbon monoxide gas and oxygen gas with oxygen gas in the mixed gas at a temperature of 100 ° C. or less in the presence of a catalyst,
The mixed gas has a hydrogen chloride concentration of less than 1% by volume,
The catalyst contains a rutile crystalline titanium oxide carrier and a ruthenium element-containing material supported on the carrier,
The ruthenium element-containing material is at least one selected from the group consisting of metal ruthenium and ruthenium compounds, a method for oxidizing carbon monoxide. According to claim 1,
The mixed gas has a relative humidity of 90% RH or less, and the method for oxidizing carbon monoxide. The method of claim 1 or 2,
The mixed gas contains air, a method for oxidizing carbon monoxide. A carbon monoxide oxidation apparatus comprising a carbon monoxide oxidation catalyst,
The carbon monoxide oxidation catalyst contains a carrier containing rutile crystalline titanium oxide, and a ruthenium element-containing material supported on the carrier,
The ruthenium element-containing material is at least one selected from the group consisting of metal ruthenium and ruthenium compounds, carbon monoxide oxidation apparatus. The method of claim 4,
Carbon monoxide oxidizer, an air purifier. A gas mask containing a carbon monoxide oxidation catalyst,
The carbon monoxide oxidation catalyst contains a carrier containing rutile crystalline titanium oxide and a ruthenium element-containing material supported on the carrier,
The ruthenium element-containing material is at least one selected from the group consisting of metal ruthenium and ruthenium compounds, gas mask.