Reaction method and reaction device

Abstract

Provided is a reaction method by which it is possible to efficiently carry out a catalyst reaction. The reaction method comprises a step for reacting not less than two types of starting materials with a metal-loaded nonwoven fabric catalyst, using a batch-type reaction device having a stirring tank.

Description

Reaction method and reaction apparatus

[0001] The present invention relates to a reaction method and a reaction apparatus.

[0002] Catalysts in which catalytic metals are supported on a carrier are widely used in reactions such as oxidation reactions and reduction reactions. For example, catalysts in which precious metals such as platinum and palladium are supported on a carrier (powder or granules) such as activated carbon or alumina are used for reduction reactions. In the field of fine chemicals, reduction reactions are carried out by introducing a solution in which raw material compounds are dissolved and the catalyst into a reaction vessel, filling it with hydrogen gas, and stirring the mixture.

[0003] However, in the above-mentioned reaction methods, a great deal of time and energy may be consumed when filtering the reaction mixture to separate the catalyst after the reaction is completed. Furthermore, in the above-mentioned reaction methods, the catalyst may not function effectively from the viewpoint of reaction efficiency, resulting in excessive reaction time being consumed or an amount of catalyst exceeding the required amount being used. In particular, in the case of granular catalysts using granular supports, the catalytic metal distributed inside the particles is not effectively utilized in the reaction. Therefore, there is a need for the development of a reaction method that can carry out catalytic reactions more efficiently.

[0004] Regarding catalysts supported on a carrier, Patent Document 1 discloses a supported catalyst having a corrugated and platelet-like shape. Patent Document 2 discloses a catalyst article including supported catalyst particles durably entangled within a porous fibrillated polymer membrane. Patent Document 3 discloses a metal-supported nonwoven fabric including a nonwoven fabric containing polyolefin fibers or PET fibers and metal particles.

[0005] JP 2016-190226 A JP 2023-59875 A Japanese Patent No. 7113866 A

[0006] An object of the present invention is to provide a reaction method capable of efficiently carrying out a catalytic reaction and a reaction apparatus used in the method.

[0007] The present invention includes the following embodiments.

[0008] [1] A reaction method comprising a step of reacting two or more raw materials in the presence of a metal-supported nonwoven fabric catalyst using a batch-type reaction apparatus having a stirring tank.

[0009] [2] The method according to [1], wherein the metal-supported nonwoven fabric catalyst comprises a nonwoven fabric containing polyolefin fibers or PET fibers and metal particles, wherein graft side chains composed of polyvinylpyrrolidone, polyacrylic acid, or a polymer having a functional group with an unshared electron pair are bonded to the nonwoven fabric, and the metal particles are supported on the graft side chains via the pyrrolidone groups of the polyvinylpyrrolidone, the carboxy groups of the polyacrylic acid, or the functional groups with the unshared electron pair.

[0010] [3] The method according to [2], wherein the metal of the metal particles is Pd, Pt, Au, Ag, Rh, Ru, Ir, Os, Cu, Ni, or an alloy of at least one of these metals.

[0011] [4] The method according to [2] or [3], wherein the functional group having an unshared electron pair is an amino group, a carboxy group, or a hydroxy group.

[0012] [5] The method according to any one of [1] to [4], wherein the metal-supported nonwoven fabric catalyst is present in the stirring tank in the form of small pieces and is not fixed.

[0013] [6] The method according to any one of [1] to [4], wherein the stirring vessel has a stirring blade therein, and the metal-supported nonwoven fabric catalyst is provided on at least a portion of the surface of the stirring blade.

[0014] [7] The method according to any one of [1] to [4], wherein the stirring vessel has a stirring blade therein, and the stirring blade is made of the metal-supported nonwoven fabric catalyst.

[0015] [8] The method according to any one of [1] to [4], wherein the stirring vessel has a baffle therein, and the metal-supported nonwoven fabric catalyst is provided on at least a portion of the surface of the baffle.

[0016] [9] The method according to any one of [1] to [4], wherein the metal-supported nonwoven fabric catalyst is provided on at least a part of the inner wall surface of the stirring vessel.

[0017]

[10] The method according to any one of [1] to [4], wherein the metal-supported nonwoven fabric catalyst is present in the stirring tank in a spherical or cylindrical form without being fixed.

[0018]

[11] The method according to any one of [1] to [4], wherein the metal-supported nonwoven fabric catalyst is fixed in the stirring tank in a cylindrical form.

[0019]

[12] The method according to any one of [1] to [4], wherein the batch reaction apparatus further has a column connected to the stirring tank, the column being filled with the metal-supported nonwoven fabric catalyst, and the method further comprises a step of circulating the raw material in the stirring tank through the column and circulating it to the stirring tank.

[0020]

[13] The method according to any one of [1] to

[12] , wherein the two or more kinds of raw materials include a gaseous raw material and a liquid raw material.

[0021]

[14] The method according to

[13] , wherein the gaseous raw material comprises hydrogen.

[0022]

[15] The method according to

[14] , wherein the liquid raw material contains at least one selected from the group consisting of unsaturated compounds, azide compounds, nitro compounds, carbonyl compounds, halogen compounds, amines protected with a benzyloxycarbonyl group, alcohols protected with a benzyloxycarbonyl group, phenols protected with a benzyloxycarbonyl group, benzyl esters, amines protected with a benzyl group, alcohols protected with a benzyl group, phenols protected with a benzyl group, and epoxides.

[0023]

[16] The method according to

[13] , wherein the gaseous raw material contains oxygen.

[0024]

[17] The method according to

[16] , wherein the liquid raw material contains at least one selected from the group consisting of an unsaturated compound, an alcohol, and an aldehyde.

[0025]

[18] The method according to any one of

[13] to

[17] , wherein the stirring vessel has stirring blades therein, and the method comprises a step of rotating the stirring blades in a state where at least a portion of the stirring blades is in contact with a gas phase containing the gaseous raw material.

[0026]

[19] The method according to any one of

[13] to

[18] , wherein the batch reaction apparatus further has an in-line mixer connected to the stirring tank, and the method comprises a step of circulating the gaseous raw material and the liquid raw material in the stirring tank through the in-line mixer, forming fine bubbles from the gaseous raw material, and circulating the fine bubbles to the stirring tank.

[0027]

[20] A batch reaction apparatus having an agitation vessel, wherein a metal-supported nonwoven fabric catalyst is provided on at least a portion of the surface of a member provided in the agitation vessel.

[0028] According to the present invention, it is possible to provide a reaction method that can efficiently carry out a catalytic reaction and a reaction apparatus used in the method.

[0029] FIG. 1 is a schematic diagram showing an example of a batch reaction apparatus used in the method according to the first embodiment. FIG. 2 is a schematic diagram showing an example of a batch reaction apparatus used in the method according to the third embodiment. FIG. 3 is a schematic diagram showing an example of a batch reaction apparatus used in the method according to the fourth embodiment. FIG. 4 is a schematic diagram showing an example of a batch reaction apparatus used in the method according to the fifth embodiment. FIG. 5 is a schematic diagram showing another example of a batch reaction apparatus used in the method according to the fifth embodiment. FIG. 6 is a schematic diagram showing an example of a batch reaction apparatus used in the method according to the sixth embodiment. FIG. 7 is a schematic diagram showing an example of a batch reaction apparatus used in the method according to the seventh embodiment. FIG. 8 is a schematic diagram showing another example of a batch reaction apparatus used in the method according to the eighth embodiment. FIG. 9 is a schematic diagram showing an example of a batch reaction apparatus used in the method according to the ninth embodiment. FIG. 10 is a schematic diagram showing another example of a batch reaction apparatus used in the method according to the ninth embodiment. FIG. 11 is a schematic diagram showing an example of a batch reaction apparatus used in the method according to the tenth embodiment.

[0030] [Reaction Method] The reaction method according to this embodiment includes a step of reacting two or more raw materials using a metal-supported nonwoven fabric catalyst in a batch reactor equipped with a stirring vessel. In this method, the reaction is carried out in a batch reactor using a metal-supported nonwoven fabric catalyst in which the metal is supported on a nonwoven fabric. Therefore, the catalyst recovery after the reaction is easier and can be performed in a shorter time than with a metal-supported catalyst in which the metal is supported on a granular carrier. Furthermore, since the metal is highly dispersed on the nonwoven fabric, the metal-supported nonwoven fabric catalyst has high reaction efficiency and can reduce the amount of metal supported. In other words, the method according to this embodiment can achieve a reaction rate and yield equivalent to or higher than conventional methods in a batch reaction while shortening the reaction time (reaction time + filtration time), thereby enabling efficient catalytic reactions. Furthermore, because metal detachment and elution from the metal-supported nonwoven fabric catalyst during the reaction are suppressed, the metal-supported nonwoven fabric catalyst can be recovered after the reaction and reused for reactions. Furthermore, since batch reactors are widely used as chemical reaction apparatuses, the method according to this embodiment can be easily carried out using existing facilities. Examples of the types of reactions that can be carried out in the reaction method according to this embodiment include reduction reactions and oxidation reactions. Details of the reaction method according to this embodiment will be described below, but the reaction method according to this embodiment is not limited to these.

[0031] (Metal-Supported Nonwoven Fabric Catalyst) The metal-supported nonwoven fabric catalyst used in the method according to this embodiment is not particularly limited as long as the catalyst component, a metal, is supported on a nonwoven fabric carrier. However, from the viewpoint of more efficient catalytic reaction, it is preferable that the metal-supported nonwoven fabric catalyst comprises a nonwoven fabric containing polyolefin fibers or PET fibers and metal particles, and the nonwoven fabric is bonded to a graft side chain composed of polyvinylpyrrolidone, polyacrylic acid, or a polymer having a functional group with an unshared electron pair, and the metal particles are supported on the graft side chain via a pyrrolidone group of the polyvinylpyrrolidone, a carboxy group of the polyacrylic acid, or the functional group with the unshared electron pair. For example, the metal particles may be supported on the graft side chain by chemical bonding (e.g., coordinate bonding) with a nitrogen atom of the pyrrolidone group, an oxygen atom of the carboxy group, or an atom with the unshared electron pair of the functional group.

[0032] In the metal-supported nonwoven fabric catalyst, metal particles are supported via pyrrolidone groups, carboxyl groups, or functional groups having unshared electron pairs possessed by the graft side chains of polyvinylpyrrolidone, polyacrylic acid, or polymers having functional groups having unshared electron pairs bonded to the nonwoven fabric. This allows small metal particles to be uniformly supported (immobilized) on the nonwoven fabric in a highly dispersed state. This increases the contact efficiency between the reaction substrate and the catalytic metal, enabling more efficient catalytic reactions. Furthermore, the amount of catalytic metal supported can be reduced. Furthermore, because the metal particles are supported on the nonwoven fabric, the catalyst can be easily separated from the reaction mixture after the reaction in a batch reactor.

[0033] <Nonwoven Fabric> The nonwoven fabric carrier may contain polyolefin fibers or PET (polyethylene terephthalate) fibers. When the fibers constituting the nonwoven fabric are made of polyolefin or PET, radicals are easily generated when the nonwoven fabric is irradiated with radiation in the graft polymerization described below. Examples of polyolefins include polyethylene, polypropylene, and a copolymer of ethylene and chlorotrifluoroethylene (ECTFE).

[0034] The basis weight of the nonwoven fabric is not particularly limited, but is preferably 50 to 500 g / m ２ It is preferable that the density is 55 to 300 g / m ２ It is more preferable that the basis weight is 50 g / m ２ When the weight per unit area is 500 g / m or more, the durability as a catalyst is improved. ２ When the temperature is below 100°C, graft polymerization by radiation can be carried out sufficiently.

[0035] <Metal Particles> The metal of the metal particles is not particularly limited, but may be a metal that acts as a catalyst. The metal may be, for example, a transition metal such as a noble metal. Specific examples include Pd, Pt, Au, Ag, Rh, Ru, Ir, Os, Cu, Ni, and alloys of at least one of these metals.

[0036] The average particle diameter of the metal particles (D ５０ The average particle diameter (D) is preferably 100 nm or less, from the viewpoint of increasing the contact efficiency between the reaction substrate and the catalytic metal when used as a catalyst and improving the catalytic activity. ５０ The average particle diameter (D) is more preferably 2 to 50 nm, and even more preferably 2 to 20 nm. ５０ ) is a value obtained by measuring the particle diameters of 50 to several hundred metal particles in a 500 nm x 500 nm area using a high-angle annular dark-field scanning transmission electron microscope (HAADF-STEM) method and calculating the average.

[0037] The amount of metal particles supported in the metal-supported nonwoven fabric catalyst may be 0.05 to 5 mass%, 0.1 to 3 mass%, 0.2 to 1 mass%, or 0.3 to 0.7 mass%. The amount of metal particles supported in the metal-supported nonwoven fabric catalyst can be measured by the following method. A small piece of a predetermined size is cut from the metal-supported nonwoven fabric catalyst, and its mass is measured. This is immersed in 1 mol / L nitric acid in a stoppered Erlenmeyer flask and stirred for 24 hours or more. The supernatant is diluted 50 times with 0.1 mol / L nitric acid. The metal concentration of this 50-fold diluted solution is measured by ICP-MS. From the measurement results, the total amount of metal eluted from the cut nonwoven fabric is calculated, and this is divided by the mass of the nonwoven fabric to determine the metal content per mass of the nonwoven fabric. This measurement is performed five times, and the average value is the amount of metal particles supported in the metal-supported nonwoven fabric catalyst.

[0038] <Graft Side Chains> Graft side chains composed of polyvinylpyrrolidone, polyacrylic acid, or a polymer having a functional group with an unshared electron pair are bonded to the nonwoven fabric. Here, the "graft side chains" refer to side chains formed by graft polymerization of a monomer (N-vinyl-2-pyrrolidone, acrylic acid, or a monomer having a functional group with an unshared electron pair) onto the fiber surface of the nonwoven fabric. Metal particles are supported on the graft side chains via a pyrrolidone group, a carboxy group, or a functional group with an unshared electron pair possessed by the graft side chains. For example, metal particles can be supported on the graft side chains by chemical bonding with the nitrogen atom of the pyrrolidone group, the oxygen atom of the carboxy group, or an atom with an unshared electron pair of the functional group. Examples of chemical bonds include coordinate bonds, ionic bonds, and hydrogen bonds. Whether the metal particles are supported on the graft side chains via the pyrrolidone group of polyvinylpyrrolidone, the carboxy group of polyacrylic acid, or the functional group having an unshared electron pair can be determined by observation with a transmission electron microscope (TEM).

[0039] As the polymer constituting the graft side chain, polyvinylpyrrolidone, polyacrylic acid, or a polymer having a functional group with an unshared electron pair is used from the viewpoint of being able to support the metal particles at multiple points on the graft side chain. In particular, polyvinylpyrrolidone is preferred because, although it has weak coordination ability with the metal of the metal particle, it can support and fix the metal particles at more multiple points with multiple pyrrolidone groups, and can sufficiently prevent the metal particles from falling off.

[0040] The functional group having an unshared electron pair is a functional group in which at least one atom constituting the functional group has an unshared electron pair, and examples thereof include an amino group, a carboxy group, a hydroxy group, etc. Specific examples of polymers having a functional group having an unshared electron pair include styrene-based polymers having primary to tertiary amino groups, polymethyl methacrylate, etc.

[0041] Grafted side chains are formed by graft polymerizing monomers onto nonwoven fabrics, and radiation-induced graft polymerization is a suitable method for this purpose. Radiation-induced graft polymerization involves irradiating an organic polymer substrate (nonwoven fabric) with radiation to generate radicals, which are then reacted with monomers, thereby introducing desired grafted side chains onto the polymer backbone of the substrate. This method allows for flexible control of the number and length of grafted side chains, and also allows for the introduction of grafted side chains into existing polymeric materials of various shapes.

[0042] Examples of radiation that can be used in radiation-induced graft polymerization include gamma rays, electron beams, and ultraviolet rays. Among these, gamma rays and electron beams are suitable for use in the present embodiment. Radiation-induced graft polymerization includes pre-irradiation graft polymerization, in which a nonwoven fabric is irradiated with radiation beforehand and then brought into contact with a monomer to cause a reaction, and simultaneous irradiation graft polymerization, in which a nonwoven fabric and a monomer are irradiated with radiation in the presence of both. Other examples include liquid-phase graft polymerization, in which polymerization is carried out while the nonwoven fabric is immersed in a monomer solution; gas-phase graft polymerization, in which polymerization is carried out by bringing the nonwoven fabric into contact with monomer vapor; and impregnation-gas-phase graft polymerization, in which a nonwoven fabric is immersed in a monomer solution and then removed from the monomer solution to cause a reaction in the gas phase. Any of these methods can be used in the present embodiment.

[0043] The nonwoven fabric used as the substrate in this embodiment is suitable for impregnation vapor-phase graft polymerization because it can easily retain a monomer solution. Because the introduction of grafted side chains into the nonwoven fabric by radiation-induced graft polymerization does not significantly reduce the mechanical strength, it is possible to introduce a large amount of grafted side chains into the nonwoven fabric.

[0044] The amount of graft side chains bonded to the nonwoven fabric is preferably 10 to 200 parts by mass per 100 parts by mass of the nonwoven fabric. By setting the amount to 10 parts by mass or more, the metal particles can be sufficiently supported on the graft side chains. Furthermore, by setting the amount to 200 parts by mass or less, deformation of the nonwoven fabric and fiber cracking can be suppressed, maintaining ease of handling. Furthermore, it is possible to prevent the catalyst metal particles from falling off due to the fibers themselves becoming brittle. The amount is a value measured by calculating the mass of the nonwoven fabric before the graft polymerization reaction and the mass of the nonwoven fabric after the graft polymerization reaction.

[0045] (Method for Producing Metal-Supported Nonwoven Fabric Catalyst) The metal-supported nonwoven fabric catalyst can be produced, for example, by a method including the following steps: a step of irradiating a nonwoven fabric containing polyolefin fibers or PET fibers with radiation and graft-polymerizing N-vinyl-2-pyrrolidone, acrylic acid, or a monomer having a functional group with an unshared electron pair onto the nonwoven fabric (hereinafter also referred to as the graft polymerization step); and a step of immersing the nonwoven fabric after graft polymerization in a solution containing a metal salt or metal oxide and a solvent (hereinafter also referred to as the solution immersion step). The method can further include a step of adding a reducing agent to the solution in which the nonwoven fabric is immersed (hereinafter also referred to as the reducing agent addition step). According to the method, the metal-supported nonwoven fabric catalyst can be produced in an appropriate manner.

[0046] <Graft Polymerization Step> In this step, a nonwoven fabric containing polyolefin fibers or PET fibers is irradiated with radiation to generate radicals in the polyolefin or PET, and the radicals are reacted with N-vinyl-2-pyrrolidone, acrylic acid, or a monomer having a functional group with an unshared electron pair to graft polymerize N-vinyl-2-pyrrolidone, acrylic acid, or the monomer. From the viewpoint of easier generation of radicals by radiation irradiation, the fibers constituting the nonwoven fabric are preferably made of polyolefin. The graft polymerization can be carried out by the radiation-induced graft polymerization method described above.

[0047] <Solution Immersion Step> In this step, the nonwoven fabric after the graft polymerization step is immersed in a solution containing a metal salt or metal oxide and a solvent. Examples of metal salts and metal oxides include salts containing the metal of the metal particles described above as a cation, and oxides of the metal, respectively. Specific examples of the metal include Pd, Pt, Au, Ag, Rh, Ru, Ir, Os, Cu, and Ni. Examples of metal salts include chlorides, hydrochlorides, nitrates, and perchlorates. These may be used alone or in combination of two or more. Examples of the solvent include water and alkaline solutions. The concentration of the metal salt or metal oxide in the solution is preferably 3 to 20 mmol / L.

[0048] When palladium chloride is used as the metal salt, the solution preferably contains palladium chloride as the metal salt, water as a solvent, and sodium chloride. By adding sodium chloride, metal fine particles can be more uniformly formed and supported.

[0049] <Reducing Agent Addition Step> In order to reduce the metal in the metal salt or metal oxide, a reducing agent may be further added to the solution in which the nonwoven fabric has been immersed after the solution immersion step. Examples of reducing agents include methanol, ethanol, propanol, polyol, sodium borohydride, and hydrazine. These reducing agents may be used alone or in combination of two or more. To promote the reduction, the solution in which the nonwoven fabric has been immersed can be heated. Reduction of the metal in the metal salt or metal oxide can be confirmed, for example, by XPS (X-ray Photoelectron Spectroscopy) or the like.

[0050] (Raw Materials) In the method according to this embodiment, two or more raw materials are used as the raw materials. In particular, in the method according to this embodiment, it is preferable that the raw materials include a gaseous raw material and a liquid raw material. When the gaseous raw material and the liquid raw material are reacted using a solid catalyst, the reaction only proceeds when the three phases of the gas phase (gas raw material), the liquid phase (gas raw material), and the solid phase (solid catalyst) come into contact with each other. In the method according to this embodiment, the gaseous raw material and the liquid raw material are reacted with stirring in the stirring tank of a batch reactor using a metal-supported nonwoven fabric catalyst, so that the three phases can come into sufficient contact with each other and the reaction can proceed efficiently.

[0051] In this embodiment, the term "gaseous feedstock" refers to a feedstock that is gaseous at room temperature (23°C) and atmospheric pressure (1 atm). Examples of the "gaseous feedstock" include a reactant (gas) diluted with a diluent gas, and the reactant (gas) itself. Examples of the diluent gas include nitrogen and argon. One of these diluent gases may be used, or two or more may be used in combination. When the "gaseous feedstock" contains the diluent gas, the amount of the reactant (gas) in the "gaseous feedstock" may be, for example, 50% by volume or more, and may be 80% by volume or more.

[0052] In this embodiment, the term "liquid raw material" refers to a raw material that is liquid at room temperature (23°C) and atmospheric pressure (1 atm). Examples of the "liquid raw material" include a reactant (solid or liquid) dissolved in a solvent, and the reactant (liquid) itself. Examples of the solvent include alcohols such as methanol, ethanol, and 2-propanol, mixtures of such alcohols with water, ethyl acetate, and toluene. These solvents may be used alone or in combination of two or more. When the "liquid raw material" contains the solvent, the amount of the reactant (solid or liquid) in the "liquid raw material" can be, for example, 50% by mass or more, and can be 80% by mass or more.

[0053] Examples of the reaction substrate contained in the gaseous raw material include hydrogen, oxygen, etc. These reaction substrates may be used alone or in combination of two or more.

[0054] When the gaseous source material contains or consists of hydrogen, a reduction reaction can be carried out using the method of this embodiment. In this case, the liquid source material can contain, as reaction substrates, unsaturated compounds (alkenes and alkynes), azide compounds, nitro compounds, carbonyl compounds, halogen compounds, benzyloxycarbonyl-protected amines, benzyloxycarbonyl-protected alcohols, benzyloxycarbonyl-protected phenols, benzyl esters, benzyl-protected amines, benzyl-protected alcohols, benzyl-protected phenols, and epoxides. The liquid source material may contain one or more of these reaction substrates. When reacting hydrogen contained in the gaseous source material with the reaction substrate contained in the liquid source using the method of this embodiment, the reaction temperature can be, for example, room temperature (23°C) to 100°C, depending on the type of reaction substrate. The reaction can be carried out under atmospheric pressure or under pressure.

[0055] When the gaseous raw material contains or consists of oxygen, an oxidation reaction can be carried out by the method according to this embodiment. In this case, the liquid raw material can contain, as a reaction substrate, for example, an unsaturated compound (alkene or alkyne), an alcohol, an aldehyde, etc. The liquid raw material may contain one or more of these reaction substrates. The reaction may be carried out under atmospheric pressure or under pressure.

[0056] (First embodiment) In this embodiment, the stirring tank of the batch reaction apparatus has a stirring blade therein, and the metal-supported nonwoven fabric catalyst is provided on at least a part of the surface of the stirring blade. By providing the metal-supported nonwoven fabric catalyst on the surface of the stirring blade, the metal-supported nonwoven fabric catalyst can be sufficiently contacted with the raw material, and the catalyst can be easily separated after the reaction.

[0057] An example of a batch reactor used in the method according to this embodiment is shown in FIG. 1 . The stirring vessel 1 shown in FIG. 1 contains a stirring blade 2, a gaseous raw material 4, and a liquid raw material 5 therein. The shape of the stirring blade 2 is not particularly limited, but examples include a propeller shape and a strip shape. A metal-supported nonwoven fabric catalyst 3 is provided on the surface of the stirring blade 2. While FIG. 1 shows the metal-supported nonwoven fabric catalyst 3 provided on the entire surface of the stirring blade 2, the metal-supported nonwoven fabric catalyst 3 may also be provided on only a portion of the surface of the stirring blade 2. When the metal-supported nonwoven fabric catalyst 3 is provided on only a portion of the surface of the stirring blade 2, it is preferable that the metal-supported nonwoven fabric catalyst 3 be provided on at least 50% of the surface area of ​​the stirring blade 2, and more preferably, that the metal-supported nonwoven fabric catalyst 3 be provided on at least 80% of the surface area of ​​the stirring blade 2. The surface area of ​​the stirring blade 2 refers to the surface area of ​​the stirring blade 2 alone, not including the shaft portion. Furthermore, the stirring blade 2 may have one or more layers of the metal-supported nonwoven fabric catalyst 3 stacked on its surface.

[0058] An example of a method for providing a metal-supported nonwoven fabric catalyst on at least a portion of the surface of the agitator blade is to attach the metal-supported nonwoven fabric catalyst to at least a portion of the surface of the agitator blade using an adhesive or the like. Alternatively, a portion of the agitator blade may be hollowed out and the metal-supported nonwoven fabric catalyst attached to cover the hollowed-out portion. Examples of the shape of the attached metal-supported nonwoven fabric catalyst include a sheet shape and a pleated shape. Examples of pleated shapes include an accordion shape, a side pleated shape, a box pleated shape, a kamaboko shape, a crystal shape, and a majolica shape. When the metal-supported nonwoven fabric catalyst has a pleated shape, the contact area between the raw material and the metal-supported nonwoven fabric catalyst increases during stirring, further improving the reaction efficiency.

[0059] (Second embodiment) In this embodiment, the stirring tank of the batch reaction apparatus has stirring blades therein, and the stirring blades are made of the metal-supported nonwoven fabric catalyst. That is, the stirring blades are made of the metal-supported nonwoven fabric catalyst, and the metal-supported nonwoven fabric catalyst also functions as a stirring blade. By making the stirring blades made of the metal-supported nonwoven fabric catalyst, the metal-supported nonwoven fabric catalyst can be sufficiently contacted with the raw material, and the catalyst can be easily separated after the reaction.

[0060] In order for the metal-supported nonwoven fabric catalyst to function sufficiently as an agitating blade, the metal-supported nonwoven fabric catalyst preferably has the pleated shape. The pleated shape of the metal-supported nonwoven fabric catalyst improves the rigidity of the metal-supported nonwoven fabric catalyst, allowing the raw materials to be thoroughly mixed during agitation. The agitating blade may be composed of one sheet of metal-supported nonwoven fabric catalyst, or two or more sheets of metal-supported nonwoven fabric catalyst.

[0061] (Third Embodiment) In this embodiment, the stirring vessel of the batch reactor has a baffle therein, and the metal-supported nonwoven fabric catalyst is provided on at least a portion of the surface of the baffle. A "baffle" is also called a baffle. While only lateral flow occurs when the stirring blade is rotated, providing the baffle can also generate vertical flow, thereby improving mixing performance. In this embodiment, providing the metal-supported nonwoven fabric catalyst on the surface of the baffle allows sufficient contact between the metal-supported nonwoven fabric catalyst and the raw material, and also facilitates catalyst separation after the reaction.

[0062] An example of a batch reactor used in the method according to this embodiment is shown in FIG. 2 . The stirred tank 1 shown in FIG. 2 contains an agitator blade 2, a gaseous raw material 4, and a liquid raw material 5. A baffle 6 is provided on the inner wall of the stirred tank 1, and a metal-supported nonwoven fabric catalyst 3 is provided on the surface of the baffle 6. While the metal-supported nonwoven fabric catalyst 3 is provided on the entire surface of the baffle 6 in FIG. 2 , the metal-supported nonwoven fabric catalyst 3 may be provided on only a portion of the surface of the baffle 6. When the metal-supported nonwoven fabric catalyst 3 is provided on only a portion of the surface of the baffle 6, the metal-supported nonwoven fabric catalyst 3 is preferably provided on at least 50% of the surface area of ​​the baffle 6, and more preferably on at least 80% of the surface area of ​​the baffle 6. Furthermore, the baffle 6 may have one or more layers of the metal-supported nonwoven fabric catalyst 3 stacked thereon. The metal-supported nonwoven fabric catalyst 3 may be provided on at least a portion of the surface of the baffle 6 using the same method as in the first embodiment.

[0063] The shape of the baffles 6 is not particularly limited, but may be, for example, flat or cylindrical. The number of baffles 6 provided in the stirred tank 1 is not particularly limited, but may be, for example, 2 to 8. When multiple baffles 6 are provided in the stirred tank 1, the baffles 6 can be provided at equal intervals along the inner wall of the stirred tank 1.

[0064] (Fourth embodiment) In this embodiment, the metal-supported nonwoven fabric catalyst is provided on at least a part of the inner wall surface of the stirring tank. In this embodiment, by providing the metal-supported nonwoven fabric catalyst on the inner wall surface of the stirring tank, the metal-supported nonwoven fabric catalyst can be sufficiently contacted with the raw material, and the catalyst can be easily separated after the reaction.

[0065] An example of a batch reactor used in the method according to this embodiment is shown in FIG. 3 . The stirred tank 1 shown in FIG. 3 has a stirring blade 2, a gaseous raw material 4, and a liquid raw material 5 therein. A metal-supported nonwoven fabric catalyst 3 is provided on the inner wall surface of the stirred tank 1. While the metal-supported nonwoven fabric catalyst 3 is shown provided on the entire inner wall surface of the stirred tank 1 in FIG. 3 , the metal-supported nonwoven fabric catalyst 3 may also be provided on only a portion of the inner wall surface of the stirred tank 1. When the metal-supported nonwoven fabric catalyst 3 is provided on only a portion of the inner wall surface of the stirred tank 1, it is preferable that the metal-supported nonwoven fabric catalyst 3 be provided on at least 50% of the area of ​​the inner wall surface of the stirred tank 1, and more preferably, that the metal-supported nonwoven fabric catalyst 3 be provided on at least 80% of the area of ​​the inner wall surface of the stirred tank 1. Furthermore, the inner wall surface of the stirred tank 1 may be provided with one layer of the metal-supported nonwoven fabric catalyst 3, or two or more layers. The same method as in the first embodiment can be used to provide the metal-supported nonwoven fabric catalyst 3 on at least a portion of the inner wall surface of the stirred tank 1.

[0066] (Fifth Embodiment) In this embodiment, the metal-supported nonwoven fabric catalyst is in a spherical or cylindrical form and is present in the stirring tank without being fixed. In this embodiment, by introducing the metal-supported nonwoven fabric catalyst having a spherical or cylindrical shape into the stirring tank without being fixed, the metal-supported nonwoven fabric catalyst can be sufficiently contacted with the raw materials during stirring, and the catalyst can be easily separated after the reaction.

[0067] An example of a batch reactor used in the method according to this embodiment is shown in FIG. 4 . The stirring tank 1 shown in FIG. 4 has a stirring blade 2, a gaseous raw material 4, and a liquid raw material 5 therein. Furthermore, a spherical metal-supported nonwoven fabric catalyst 3 is disposed in the liquid raw material 5 of the stirring tank 1 without being fixed thereto. That is, the spherical metal-supported nonwoven fabric catalyst 3 floats or sinks in the liquid raw material 5. The number of spherical metal-supported nonwoven fabric catalysts 3 disposed in the stirring tank 1 may be one or more. When multiple spherical metal-supported nonwoven fabric catalysts 3 are disposed in the stirring tank 1, the multiple spherical metal-supported nonwoven fabric catalysts 3 may be bundled in a single mesh and disposed in the stirring tank 1. The spherical metal-supported nonwoven fabric catalyst 3 can be obtained by rolling a sheet-shaped metal-supported nonwoven fabric catalyst into a spherical shape. For example, the spherical metal-supported nonwoven fabric catalyst can be obtained by welding the sheet-shaped metal-supported nonwoven fabric catalyst to form a spherical shape, or by binding the sheet-shaped metal-supported nonwoven fabric catalyst with wire or the like. Furthermore, an appropriate weight may be placed in the center of the spherical metal-supported nonwoven fabric catalyst 3 so that the spherical metal-supported nonwoven fabric catalyst 3 can easily float or sink in the liquid raw material 5 (the wire may also function as a weight). Note that in this embodiment, the term "spherical" may refer to a roughly spherical shape that is appropriately rounded.

[0068] Another example of a batch reactor used in the method according to this embodiment is shown in FIG. 5 . The stirred tank 1 shown in FIG. 5 is similar to that shown in FIG. 4 , except that a cylindrical metal-supported nonwoven fabric catalyst 3 is disposed in the stirred tank 1 without being fixed thereto, instead of the spherical metal-supported nonwoven fabric catalyst. The number of cylindrical metal-supported nonwoven fabric catalysts 3 disposed in the stirred tank 1 may be one or two or more. When multiple cylindrical metal-supported nonwoven fabric catalysts 3 are disposed in the stirred tank 1, the multiple cylindrical metal-supported nonwoven fabric catalysts 3 may be bundled in a single mesh and disposed in the stirred tank 1. The cylindrical metal-supported nonwoven fabric catalyst 3 can be obtained by rolling a sheet-shaped metal-supported nonwoven fabric catalyst into a cylindrical shape. For example, the cylindrical metal-supported nonwoven fabric catalyst can be obtained by welding the sheet-shaped metal-supported nonwoven fabric catalyst to form a cylindrical shape, or by binding the sheet-shaped metal-supported nonwoven fabric catalyst with wire or the like. Furthermore, an appropriate weight may be placed in the core of the cylindrical metal-supported nonwoven fabric catalyst 3 so that the cylindrical metal-supported nonwoven fabric catalyst 3 can easily float or sink in the liquid raw material 5 (the wire can also function as a weight). In this embodiment, the term "cylindrical" may refer to a roughly cylindrical shape that is somewhat rolled into a cylindrical shape.

[0069] (Sixth Embodiment) In this embodiment, the metal-supported nonwoven fabric catalyst is present in the form of small pieces in the stirring vessel without being fixed. In this embodiment, by introducing the metal-supported nonwoven fabric catalyst in the form of small pieces into the stirring vessel without fixing it, the metal-supported nonwoven fabric catalyst can be sufficiently contacted with the raw materials during stirring, and the catalyst can be easily separated after the reaction. In this embodiment, the "small pieces" can be, for example, pieces with a maximum across length of 10 mm or more, or can be pieces with a maximum across length of 10 to 300 mm. Furthermore, the "maximum across length" refers to the longest across length of the small pieces; for example, if the small pieces are rectangular, the diagonal line is the maximum across length.

[0070] An example of a batch reactor used in the method according to this embodiment is shown in FIG. 6 . The stirring vessel 1 shown in FIG. 6 has a stirring blade 2, a gaseous raw material 4, and a liquid raw material 5 therein. Furthermore, small flake-shaped metal-supported nonwoven fabric catalysts 3 are disposed in the liquid raw material 5 of the stirring vessel 1 without being fixed thereto. That is, the small flake-shaped metal-supported nonwoven fabric catalysts 3 float or sink in the liquid raw material 5. The number of small flake-shaped metal-supported nonwoven fabric catalysts 3 disposed in the stirring vessel 1 may be one or two or more. The small flake-shaped metal-supported nonwoven fabric catalysts 3 may be, for example, triangular, rectangular, polygonal, circular, elliptical, or torn free-form. The small flake-shaped metal-supported nonwoven fabric catalysts 3 can be obtained, for example, by cutting a large sheet-shaped metal-supported nonwoven fabric catalyst into the desired size and shape.

[0071] (Seventh embodiment) In this embodiment, the metal-supported nonwoven fabric catalyst is fixed in the stirring tank in a cylindrical shape. In this embodiment, by fixing the metal-supported nonwoven fabric catalyst in a cylindrical shape in the stirring tank, the metal-supported nonwoven fabric catalyst can be sufficiently contacted with the raw material, and the catalyst can be easily separated after the reaction.

[0072] An example of a batch reactor used in the method according to this embodiment is shown in FIG. 7 . The stirred tank 1 shown in FIG. 7 contains an impeller 2, a gaseous raw material 4, and a liquid raw material 5. A cylindrical metal-supported nonwoven fabric catalyst 3 is attached to the inner wall of the stirred tank 1, approximately parallel to the axis of the impeller 2. Specifically, the cylindrical metal-supported nonwoven fabric catalyst 3 is located approximately parallel to the axis of the impeller 2 in the region between the impeller 2 and the inner wall of the stirred tank 1. Note that "approximately parallel" refers to an angle of ±5°C. The cylindrical metal-supported nonwoven fabric catalyst 3 can be produced, for example, by wrapping multiple layers of a sheet-shaped metal-supported nonwoven fabric catalyst 3 around a cylindrical core. Alternatively, the sheet-shaped metal-supported nonwoven fabric catalyst 3 may be rolled into a cylindrical shape without using a core. The number of cylindrical metal-supported nonwoven fabric catalysts 3 provided in the stirred tank 1 is not particularly limited, but may be, for example, 2 to 8. When multiple cylindrical metal-supported nonwoven fabric catalysts 3 are provided in the stirring tank 1, the cylindrical metal-supported nonwoven fabric catalysts 3 can be provided at equal intervals along the inner wall of the stirring tank 1. The cylindrical metal-supported nonwoven fabric catalyst 3 shown in Figure 7 can also function as the baffle described above. Note that, although the cylindrical metal-supported nonwoven fabric catalyst 3 is attached to the side surface of the inner wall of the stirring tank 1 in Figure 7, the cylindrical metal-supported nonwoven fabric catalyst 3 may be inserted into or wrapped around multiple supports extending upward from the bottom of the stirring tank 1.

[0073] Another example of a batch reactor used in the method according to this embodiment is shown in FIG. 8 . The stirred tank 1 shown in FIG. 8 has an impeller 2, a gaseous raw material 4, and a liquid raw material 5 therein. A large cylindrical frame 7 is fixedly disposed within the stirred tank 1, extending substantially parallel to the axis of the impeller 2. Specifically, the cylindrical frame 7 is disposed substantially parallel to the axis of the impeller 2 in the region between the impeller 2 and the inner wall of the stirred tank 1. The cylindrical frame 7 located on the left side of FIG. 8 and the cylindrical frame 7 located on the right side of FIG. 8 represent the cross section of the same large cylindrical frame. That is, one large cylindrical frame 7 is fixedly disposed within the stirred tank 1, and the impeller 2 is located inside the cylindrical frame 7 (near the central axis). A metal-supported nonwoven fabric catalyst 3 is disposed on the surface of this cylindrical frame 7. That is, the metal-supported nonwoven fabric catalyst 3 is fixedly disposed within the stirred tank 1 in a cylindrical form. The metal-supported nonwoven fabric catalyst 3 may be disposed on the inner surface or the outer surface of the cylindrical frame 7, or may be disposed on both the inner and outer surfaces as shown in FIG. 8 . One or more metal-supported nonwoven fabric catalysts 3 may be layered on the surface of the cylindrical frame 7. The same method as in the first embodiment can be used to provide the metal-supported nonwoven fabric catalyst 3 on the surface of the cylindrical frame 7. The inner and outer portions of the cylindrical frame 7 may be spatially connected to the extent that this does not cause nonuniformity in the solution flow and temperature in the stirring tank 1.

[0074] Eighth Embodiment In this embodiment, the batch reactor further includes a column connected to the stirring tank, and the column is filled with the metal-supported nonwoven fabric catalyst. The method according to this embodiment includes a step of circulating the raw material in the stirring tank through the column and circulating it to the stirring tank. In this embodiment, the raw material is circulated through the column filled with the metal-supported nonwoven fabric catalyst and then circulated to the stirring tank, so that the metal-supported nonwoven fabric catalyst can be sufficiently contacted with the raw material, and catalyst separation after the reaction is not required.

[0075] Another example of a batch reactor used in the method according to this embodiment is shown in Figure 9. The stirred tank 1 shown in Figure 9 has an impeller 2, a gaseous raw material 4, and a liquid raw material 5 therein. A pump 8 and a column 9 filled with a metal-supported nonwoven fabric catalyst are connected to the stirred tank 1, and the pump 8 and column 9 are disposed outside the stirred tank 1. In the batch reactor shown in Figure 9, the gaseous raw material 4 and the liquid raw material 5 are removed from the stirred tank 1 by the pump 8, circulated through the column 9 disposed downstream of the pump 8, and then circulated back into the stirred tank 1. Although the stirred tank 1 in Figure 9 has an impeller 2 therein, the impeller 2 need not be provided.

[0076] Ninth Embodiment In this embodiment, the stirring vessel of the batch reactor has a stirring blade within the vessel. The method according to this embodiment also includes a step of rotating the stirring blade while at least a portion of the stirring blade is in contact with a gas phase containing the gaseous raw material. One method for efficiently contacting the three components of gas, liquid, and solid is to generate a large number of fine gas bubbles in the liquid by stirring. In this embodiment, the stirring blade is rotated while at least a portion of the stirring blade is in contact with the gas phase containing the gaseous raw material, i.e., while at least a portion of the stirring blade is above the liquid surface. This allows for the generation of a large number of fine bubbles of the gaseous raw material in the liquid. This allows for efficient contact between the gaseous raw material, the liquid raw material, and the metal-supported nonwoven fabric catalyst, and allows for more efficient catalytic reaction. The configuration according to this embodiment can be used in combination with the first to eighth embodiments described above.

[0077] An example of a batch reactor used in the method according to this embodiment is shown in FIG. 10 . The stirring vessel 1 shown in FIG. 10 contains a stirring blade 2, a gaseous feedstock 4, and a liquid feedstock 5. A portion of the stirring blade 2 protrudes above the liquid surface of the liquid feedstock 5 and is in contact with the gaseous feedstock 4. As the stirring blade 2 rotates in this state, fine bubbles of the gaseous feedstock 4 are generated within the liquid feedstock 5. When the stirring blade 2 is stationary, preferably 10 to 80% of the surface area of ​​the stirring blade 2 is in contact with the gaseous feedstock 4, and more preferably 20 to 50%. The rotation speed of the stirring blade 2 during stirring can be, for example, 60 to 600 rpm, depending on the size and shape of the stirring blade 2. The stirring blade 2 may be installed approximately parallel to the horizontal plane and in contact with the gaseous feedstock 4 as shown in FIG. 10 , or it may be installed at an angle to the horizontal plane and in contact with the gaseous feedstock 4 as shown in FIG. 11 .

[0078] (Tenth Embodiment) In this embodiment, the batch reactor further includes an in-line mixer connected to the stirring tank. The method according to this embodiment also includes a step of circulating the gaseous raw material and liquid raw material in the stirring tank through the in-line mixer, converting the gaseous raw material into fine bubbles, and circulating the bubbles to the stirring tank. In this embodiment, the gaseous raw material is converted into fine bubbles in the in-line mixer, which allows the gaseous raw material, liquid raw material, and metal-supported nonwoven fabric catalyst to come into contact with each other efficiently, thereby enabling the catalytic reaction to be carried out more efficiently. The configuration according to this embodiment can be used in combination with the first to ninth embodiments described above.

[0079] An example of a batch reactor used in the method according to this embodiment is shown in FIG. 12 . The stirred tank 1 shown in FIG. 12 has an agitator blade 2, a gaseous raw material 4, and a liquid raw material 5 inside the tank. A pump 8 and an in-line mixer 10 are connected to the stirred tank 1, and the pump 8 and the in-line mixer 10 are disposed outside the stirred tank 1. In the batch reactor shown in FIG. 12 , the gaseous raw material 4 and the liquid raw material 5 are removed from the stirred tank 1 by the pump 8, circulated through the in-line mixer 10 disposed downstream of the pump 8, and then circulated back into the stirred tank 1. The in-line mixer 10 is a fine bubble generating in-line mixer that can convert the gaseous raw material 4 into fine bubbles with a diameter of less than 100 μm, for example. In this embodiment, a metal-supported nonwoven fabric catalyst is preferably attached to the inside of the piping in the downstream region 11 of the in-line mixer 10. Because the flow velocity is particularly high in the downstream region 11 of the in-line mixer 10, arranging the metal-supported nonwoven fabric catalyst in this region allows fine bubbles of the gaseous raw material 4 to come into contact with the liquid raw material 5 and the metal-supported nonwoven fabric catalyst more efficiently. Note that attaching the metal-supported nonwoven fabric catalyst so as to block the inside of the piping in the downstream region 11 of the in-line mixer 10 may increase pressure loss, so it is preferable to attach the metal-supported nonwoven fabric catalyst to the inner wall of the piping, making it hollow and leaving a passageway for the raw material in the center.

[0080] [Reaction Apparatus] The reaction apparatus according to this embodiment is a batch-type reaction apparatus having a stirring vessel, in which a metal-supported nonwoven fabric catalyst is provided on at least a portion of the surface of a component provided in the stirring vessel. In the reaction apparatus according to this embodiment, the metal-supported nonwoven fabric catalyst is provided on the surface of a component in the stirring vessel of the batch-type reaction apparatus, allowing for sufficient contact between the metal-supported nonwoven fabric catalyst and the raw materials, and facilitating catalyst separation after the reaction. Examples of components provided in the stirring vessel include stirring blades, baffles, and the inner wall of the stirring vessel. As the reaction apparatus according to this embodiment, for example, the reaction apparatuses according to the first to fourth and seventh embodiments described above can be suitably used.

[0081] The present invention will be described in detail below with reference to examples, but the present invention is not limited to the following description.

[0082] Example 1 Preparation of Palladium-Supported Nonwoven Fabric A nonwoven fabric made of polyethylene fibers (product name: OX8901-T6, manufactured by Nippon Vilene Co., Ltd., 18 cm x 30 cm, basis weight: 62 g / m) was prepared. ２ The nonwoven fabric was irradiated with an electron beam (245 keV) (irradiated energy: 150 kGy). The nonwoven fabric was immersed in a 30% by mass aqueous solution of N-vinyl-2-pyrrolidone and reacted at 60°C for 1 hour to produce a PVP-grafted nonwoven fabric in which approximately 90 parts by mass of N-vinyl-2-pyrrolidone was grafted per 100 parts by mass of the nonwoven fabric (grafted side chain: polyvinylpyrrolidone).

[0083] Next, 0.731 g of sodium chloride and 0.4433 g of palladium chloride were dissolved in 250 mL of pure water to prepare a chloropalladium acid aqueous solution. The PVP-grafted nonwoven fabric cut into a size of 300 mm x 200 mm was immersed in the aqueous solution (45 mL), excess chloropalladium acid aqueous solution was removed using a wringer, and the fabric was dried in a dryer at 50°C for at least 2 hours.

[0084] The dried nonwoven fabric was rolled up and placed in a 150 x 20 mm glass column, a gas pipe was attached, and hydrogen purging was performed. After purging, the glass column was submerged in a thermostatic bath heated to 80°C and heated for 6 hours while flowing hydrogen gas at 5 ml / min (back pressure: 0.05 MPa). After the reduction step was completed, the nonwoven fabric was washed with pure water to remove remaining Na ions and detached palladium from the nonwoven fabric, yielding a palladium-supported nonwoven fabric.

[0085] From the palladium-carrying nonwoven fabric obtained as described above, three rectangular pieces of 2 cm x 1 cm (6 cm ２) was cut out, and its mass was measured. This was immersed in 1 mol / L nitric acid (25 ml) in a stoppered Erlenmeyer flask and stirred for 24 hours or more. This supernatant (500 μl) was diluted 50 times with 0.1 mol / L nitric acid to a total of 25 ml. The palladium concentration of this 50-fold diluted solution was measured by ICP-MS. From the measurement results, the total amount of palladium eluted from the cut-out nonwoven fabric was calculated, and divided by the mass of the nonwoven fabric to determine the palladium content per mass of the nonwoven fabric. This measurement was performed five times, and the average value was taken as the amount of palladium supported in the palladium-supported nonwoven fabric. As a result, the amount of palladium supported in the palladium-supported nonwoven fabric was 0.56 mass%.

[0086] Furthermore, the palladium-supported nonwoven fabric was observed with a scanning electron microscope (SEM) and subjected to X-ray analysis, confirming that palladium (Pd) metal nanoparticles (D50: 100 nm or less) were attached to the nonwoven fabric. Furthermore, analysis of the bonding state by XPS confirmed a peak at 335.4 eV in the photoelectron spectrum attributable to a palladium metal bond (zero valence). Furthermore, observation by TEM / STEM confirmed that the palladium particles were supported via the pyrrolidone groups of the polyvinylpyrrolidone graft side chains.

[0087] (Hydrogenation of Nitrobenzene Using Palladium-Supported Nonwoven Fabric) A 2-propanol solution of nitrobenzene (0.1 mol / l, 150 ml) was poured into a reaction vessel (300 ml, three-neck). ２ , 660 mg, net Pd amount: 3.7 mg) were cut into rectangular pieces of 1 cm x 2 cm and 32 pieces were added.

[0088] A rubber balloon was attached to a thick rubber tube and secured with a rubber band, and the balloon was filled with hydrogen gas (3 liters) and inflated. The inflated balloon was attached to a three-way stopcock, and the three-way stopcock was attached to the reaction vessel (three-neck side). A stirring blade was installed in the center of the three-neck of the reaction vessel, and a rubber septum was attached to the other three-neck side, sealing the reaction vessel.

[0089] The three-way cock was connected to a diaphragm pump with a thick-walled rubber tube, and stirring (120 rpm) was started. The diaphragm pump was turned on and the air in the reaction vessel was sucked out. 30 seconds after the start of suction, the three-way cock was turned on, and hydrogen gas was passed from the rubber balloon into the reaction vessel, replacing the air. The above suction and hydrogen replacement operations were repeated once more. The temperature of the reaction solution was raised to 30°C, and the stirring speed was increased to 200 rpm to start the reaction.

[0090] Sampling of the reaction solution (30 minutes, 1 hour, 3 hours, 6 hours, and 24 hours after the start of the reaction) was performed using the following procedure. First, stirring of the reaction solution was temporarily stopped. Next, the three-way stopcock was shut off, a syringe was inserted through the rubber septum, and the reaction solution (3 ml) was sampled and transferred to a vial. The three-way stopcock was returned to the hydrogen replacement state, and stirring was resumed.

[0091] The five reaction solution samples obtained were analyzed by HPLC to measure the yield of the target compound, aniline, and to examine changes over time during the reaction. The HPLC system used was an Agilent 1260 Infinity II, and the column used was an Agilent Poroshell 120 EC-C18 (particle size 2.7 μm, φ3 × 150 mm). The mobile phase used was an aqueous ammonium acetate-acetonitrile system (flow rate: 0.5 ml / min). The yield was calculated from the peak area based on previously prepared calibration curves for nitrobenzene and aniline. The results are shown in Table 1.

[0092] The palladium-supported nonwoven fabric was removed from the reaction mixture after 24 hours of reaction. The time required for removal of the palladium-supported nonwoven fabric was less than 5 minutes, and the palladium-supported nonwoven fabric could be easily separated from the reaction mixture in a short time. The resulting reaction mixture (135 ml) was a clear liquid containing no solids.

[0093] The reaction mixture was directly introduced into a rotary evaporator, and 2-propanol was distilled off to obtain 12.4 g (13.3 mmol, isolated yield 98.5%) of the target compound, aniline. When the 1H-NMR spectrum of the obtained residue was examined (solvent: deuterated chloroform), -NH ２(δ 3.61 ppm, 2H), the 2nd and 6th positions of the benzene ring (δ 6.67 ppm, 2H), the 4th position of the benzene ring (δ 6.75 ppm, 1H), and the 3rd and 5th positions of the benzene ring (δ 7.14 ppm, 2H) were observed, confirming that the product was aniline.

[0094] Comparative Example 1 (Preparation of Palladium Activated Carbon) Fine powder of 10% palladium activated carbon (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was prepared as a hydrogenation catalyst.

[0095] (Hydrogenation of nitrobenzene using palladium-activated carbon) A 2-propanol solution of nitrobenzene (0.1 mol / l, 150 ml) was poured into a reaction vessel (300 ml, three-necked), and the 10% palladium-activated carbon (38 mg, net Pd amount: 3.8 mg) was added to the reaction vessel.

[0096] A rubber balloon filled with hydrogen gas (3 liters), a three-way cock, and a rubber septum were attached to the reaction vessel in the same manner as in Example 1. Furthermore, the atmosphere inside the reaction vessel was replaced with hydrogen in the same manner as in Example 1, and the mixture was stirred at 200 rpm to start the reaction.

[0097] Sampling of the reaction solution was performed five times, as in Example 1, at 30 minutes, 1 hour, 3 hours, 6 hours, and 24 hours after the start of the reaction. The procedure involved temporarily halting the stirring of the reaction solution and allowing it to stand for approximately 5 minutes until the supernatant of the suspended reaction solution became somewhat transparent. Next, the three-way stopcock was shut off, a syringe was inserted through the rubber septum, and the reaction solution (3 ml) was sampled and transferred to a vial. Since the sampled reaction solution was still suspended, it was filtered using a filter (Millex-HPF Filter, 0.45 μm) and a syringe. This filtration procedure took approximately 10 minutes per sample.

[0098] The five reaction solution samples obtained were analyzed by HPLC in the same manner as in Example 1 to measure the yield of the target compound, aniline, and to examine the change over time of the reaction. The results are shown in Table 1.

[0099] The reaction mixture (135 ml) obtained after 24 hours of reaction was a suspension containing fine powder of palladium-activated carbon, and was filtered using a glass filter lined with Celite to obtain a transparent liquid. This filtration procedure took approximately 20 minutes. Celite with palladium-activated carbon attached was generated as waste. It is possible to prevent the generation of waste Celite by using a filter (Millex-HPF Filter, 0.45 μm) during filtration, but this method takes even longer and generates a filter with palladium-activated carbon attached.

[0100] The liquid was introduced into a rotary evaporator, and 2-propanol was distilled off to obtain 11.8 g (12.7 mmol, isolated yield 94.1%) of the target compound, aniline.

[0101]

[0102] As shown in Table 1, Example 1, in which the palladium-supported nonwoven fabric according to this embodiment was used, achieved a hydrogenation reaction rate equivalent to that of Comparative Example 1, in which 10% palladium-activated carbon with an equivalent net Pd content was used. Furthermore, in Example 1, the palladium-supported nonwoven fabric after completion of the reaction was washed with 2-propanol, wiped dry, and then hydrogenation of nitrobenzene was carried out under the same conditions. As with the first reaction, aniline was obtained in almost 100% yield in 24 hours in both the second and third runs. This confirmed that the palladium-supported nonwoven fabric according to this embodiment can be reused multiple times. On the other hand, in the case of the palladium-activated carbon of Comparative Example 1, a portion of the palladium was eluted into the reaction solution, making it difficult to recover the eluted palladium. Furthermore, the palladium-activated carbon was recovered by filtration as a mixture with a filter medium, making reuse difficult.

[0103] DESCRIPTION OF SYMBOLS 1 Stirring vessel 2 Stirring blade 3 Metal-supported nonwoven fabric catalyst 4 Gaseous raw material 5 Liquid raw material 6 Baffle 7 Cylindrical frame 8 Pump 9 Column 10 In-line mixer 11 Downstream region of in-line mixer

Claims

1. A reaction method comprising the step of reacting two or more raw materials using a batch reactor equipped with a stirring tank with a metal-supported nonwoven fabric catalyst.

2. The method according to claim 1, wherein the metal-supported nonwoven fabric catalyst comprises a nonwoven fabric containing polyolefin fibers or PET fibers and metal particles, wherein graft side chains composed of polyvinylpyrrolidone, polyacrylic acid, or a polymer having a functional group with an unshared electron pair are bonded to the nonwoven fabric, and the metal particles are supported on the graft side chains via the pyrrolidone groups of the polyvinylpyrrolidone, the carboxy groups of the polyacrylic acid, or the functional group with the unshared electron pair.

3. The method of claim 2, wherein the metal of the metal particles is Pd, Pt, Au, Ag, Rh, Ru, Ir, Os, Cu, Ni, or an alloy of at least one of these metals.

4. The method according to claim 2 or 3, wherein the functional group having an unshared electron pair is an amino group, a carboxy group, or a hydroxy group.

5. The method according to any one of claims 1 to 4, wherein the metal-supported nonwoven fabric catalyst is present in the stirring tank in the form of small pieces without being fixed.

6. The method according to any one of claims 1 to 4, wherein the stirring vessel has a stirring blade therein, and the metal-supported nonwoven fabric catalyst is provided on at least a portion of the surface of the stirring blade.

7. The method according to any one of claims 1 to 4, wherein the stirring vessel has a stirring blade therein, and the stirring blade is made of the metal-supported nonwoven fabric catalyst.

8. The method according to any one of claims 1 to 4, wherein the stirring vessel has a baffle therein, and the metal-supported nonwoven fabric catalyst is provided on at least a portion of the surface of the baffle.

9. The method according to any one of claims 1 to 4, wherein the metal-supported nonwoven fabric catalyst is provided on at least a portion of the inner wall surface of the stirring vessel.

10. The method according to any one of claims 1 to 4, wherein the metal-supported nonwoven fabric catalyst is present in the stirring tank in the form of spheres or cylinders without being fixed.

11. The method according to any one of claims 1 to 4, wherein the metal-supported nonwoven fabric catalyst is fixed in the stirring tank in the form of a cylinder.

12. The method according to any one of claims 1 to 4, wherein the batch reaction apparatus further comprises a column connected to the stirring tank, the column being packed with the metal-supported nonwoven fabric catalyst, and the method further comprises a step of circulating the raw material in the stirring tank through the column and circulating it to the stirring tank.

13. The method of any one of claims 1 to 12, wherein the two or more feedstocks include a gaseous feedstock and a liquid feedstock.

14. The method of claim 13, wherein the gaseous feed comprises hydrogen.

15. The method of claim 14, wherein the liquid source comprises at least one selected from the group consisting of unsaturated compounds, azide compounds, nitro compounds, carbonyl compounds, halogen compounds, benzyloxycarbonyl-protected amines, benzyloxycarbonyl-protected alcohols, benzyloxycarbonyl-protected phenols, benzyl esters, benzyl-protected amines, benzyl-protected alcohols, benzyl-protected phenols, and epoxides.

16. The method of claim 13, wherein the gaseous feed comprises oxygen.

17. The method of claim 16, wherein the liquid feedstock comprises at least one member selected from the group consisting of unsaturated compounds, alcohols, and aldehydes.

18. The method according to any one of claims 13 to 17, wherein the stirring vessel has stirring blades within the vessel, and the method comprises a step of rotating the stirring blades in a state where at least a portion of the stirring blades is in contact with a gas phase containing the gaseous raw material.

19. The method according to any one of claims 13 to 18, wherein the batch reactor further has an in-line mixer connected to the stirring tank, and the method comprises the steps of circulating the gaseous raw material and liquid raw material in the stirring tank through the in-line mixer, forming fine bubbles from the gaseous raw material, and circulating the fine bubbles to the stirring tank.

20. A batch reaction apparatus having an agitation vessel, in which a metal-supported nonwoven fabric catalyst is provided on at least a portion of the surface of a member provided in the agitation vessel.

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