JP5539091B2 - Method for producing metal particle supported catalyst, metal particle supported catalyst and reaction method. - Google Patents

Description

  The present invention relates to a metal particle-supported catalyst in which a metal is supported on a support material, a technique for producing the metal particle-supported catalyst, and a technique for advancing a reaction using the metal particle-supported catalyst.

  Catalysts are used in various fields such as organic substance synthesis and purification of automobile exhaust gas, in addition to promoting reaction in fuel cells. As such a catalyst, a porous material such as alumina or silica or a porous material such as carbon is used as a carrier material, and a catalyst in which platinum, rhodium, or the like, which is an active metal, is supported, or a plurality of metals are supported. Multi-component catalysts are known. As the support material, various materials such as zeolite, silica-alumina composite, ceria, tin oxide, ATO, ITO, and antimony pentoxide are used in addition to those described above.

  The active metal supported on the support material is supported in a small particle size, such as colloidal particles, in order to increase the surface area per unit weight and to exhibit the properties as an active metal and interaction with the support material. Often. As one of the typical methods for producing a conventional metal particle-supported catalyst in which colloidal particles containing metal are supported on a support material, dinitrodiammine platinum, chloroplatinic acid, rhodium nitrate is applied to a support made of a porous metal oxide. A method of impregnating such a metal salt solution and firing in a reducing atmosphere is known. Also for the multi-component catalyst, a production method is known in which a solution of a plurality of metal salts to be supported is prepared, a carrier is mixed with the solution, a plurality of metal ions are adsorbed on the carrier, and then dried and calcined. Yes.

  In order to increase the specific surface area of the support material, catalysts have been developed in which metal particles are supported on a nano-order support instead of a micron order. For such a catalyst, a method in which metal ions are reduced on the support surface to deposit and coat the metal is known, but there are polymers and surfactants used as a structure control agent when depositing metal particles. There are many problems that exist on the particle surface and the catalytic activity is low, and that the metal is not coated on the particle surface and exists as a single colloid.

  In addition to the examples of the production method described above, some prior art examples of a method for producing a metal particle-supported catalyst in which colloidal particles containing a metal are supported on a support material will be given. Patent Document 1 discloses a wavelength that matches the absorption band of at least one raw material for synthesizing the carrier in the method of depositing the fine metal particles having catalytic activity on the surface of the fine carrier particles made of a metal oxide or the like. The step of irradiating the raw material with light containing the material and precipitating the carrier particles, and the raw material for precipitating the deposited carrier particles and the metal particles having catalytic activity, simultaneously in the absorption band of the raw material Disclosed is a method for producing a catalyst, characterized by comprising a step of irradiating light containing a matching wavelength and depositing the metal particles on the surface of the carrier particles, and a step of selectively collecting the deposited metal particles. Has been.

  In Patent Document 2, metal particles and / or metal compound particles are adsorbed on a solid support together with an organic polymer compound having a number average molecular weight of 3,000 to 300,000 that protects the particles substantially individually and separately. And / or metal particles characterized in that at least one of the polymer compound and the solid support does not have a functional group capable of forming a covalent bond and forming a chemical bond therebetween. Alternatively, a metal compound particle-supported composite is described. The production method includes a dispersion medium, metal particles and / or metal compound particles, and an organic polymer compound having a number average molecular weight of 3,000 to 300,000 having a protective colloid particle action, and the particles are contained in the dispersion medium. A colloidal particle dispersion comprising: a colloidal particle dispersed to form a colloidal particle; and the polymer adsorbed on the particle to protect the particle substantially individually and separately as a protective colloidal particle. Contacting the particle dispersion with a solid support, wherein at least one of the polymer compound and the solid support does not have a functional group capable of forming a covalent bond and creating a chemical bond therebetween, thus The particles protected with the polymer compound are adsorbed on the solid support to form a particle-supported complex, and the resulting complex is isolated from the dispersion medium.

  In Patent Document 3, propargyl alcohol is added to a solution containing a carrier on which metal-containing ions and metal particles generated by reduction of the metal-containing ions are supported, and a reaction product of the metal-containing ions and propargyl alcohol is added to the carrier. After being supported on the substrate, the support is heat-treated in a reducing gas containing hydrogen gas to reduce a reaction product of metal-containing ions and propargyl alcohol on the support to metal-containing colloidal particles. A method for producing a highly dispersed metal-containing colloidal particle supported catalyst is disclosed.

  In Patent Document 4, in the presence of a solid substance serving as a carrier, a liquid having a reducing ability containing a metal compound or ions or a liquid in which a reducing substance is dissolved is irradiated with microwaves, or a metal compound or A metal-containing colloidal particle is attached to the surface, characterized by having a solid substance serving as a carrier after a microwave is irradiated to a liquid containing a reducing ability or containing a reducing substance containing ions. In addition, a method for producing a metal-containing colloidal particle adhesion carrier is disclosed.

  Patent Document 5 contains at least one second element of Group 2B, Group 3B, Group 4B, Group 5B, Group 6B, and Group 8 of the Period 4 to Period 6 of the periodic table and gold. A metal particle carrier in which metal particles are supported on a carrier, and a production method comprising heat treating a carrier containing at least one of gold and its compound and at least one of a second element and its compound as a production method thereof A method is disclosed.

  Patent Document 6 discloses a dispersion of metal oxide particles (A-1) surface-treated with an amino group-containing silane compound, and metal colloid particles (M) surface-treated with a carboxyl group and / or carboxylate group-containing organic compound. -1) A method for producing conductive composite particles and conductive composite particles characterized by mixing with a dispersion liquid are disclosed.

  In Patent Document 7, hydrogen gas is supplied to a dispersion containing at least one kind of fine particles selected from metal fine particles, metal oxide fine particles, and metal-coated metal oxide fine particles, an organic stabilizer, and a dispersion medium. Then, after hydrogen is adsorbed on the surface of the fine particles, a metal salt is added to the dispersion, and the metal salt is reduced by hydrogen adsorbed on the surface of the fine particles to deposit metal on the fine particles. A method for producing composite fine particles and conductive composite particles characterized by forming a surface layer are disclosed.

  As described above, many methods for producing a metal particle-supported catalyst by supporting fine metal particles on a support material have been developed. For example, the catalyst performance in terms of improving the activity of the catalyst, extending its life, and improving the electrical characteristics. There was a need for further improvement.

Japanese Patent Laid-Open No. 61-268359: Claim 1 JP-A-5-293383: Claims 1 and 4 JP-A-6-31181: Claim 1 Japanese Patent Laying-Open No. 2003-13105: Claim 1 Japanese Patent Laid-Open No. 2003-053188: Claims 1 and 2 JP 2008-3111141 A: Claims 1 and 2 JP-A-11-12608: Claims 1 and 2

  The present invention relates to a metal particle-supported catalyst in which metal nanoparticles are supported and coated on a nano-order carrier that has improved catalyst performance and electrical characteristics in terms of activity improvement and life extension compared to conventional metal particle-supported catalysts. It is an object of the present invention to provide a production method, a metal particle-supported catalyst, and a reaction method using the catalyst.

1st invention is the manufacturing method of the metal particle supported catalyst characterized by including the process of following [1]-[4].
[1] The following (Ia) to (Ic) are selected from the following (Ia) to (Ic) for the first suspension in which the carrier material containing the ion exchanger (the average particle diameter of primary particles is 1 to 500 nm) is dispersed in a solvent. One or more kinds of metal ions are added at a ratio of 0.1 to 100 parts by mass in terms of metal elements with respect to 100 parts by mass of the carrier substance, and the metal ions are supported on the carrier substance to prepare a suspension A. Process.
(Ia) Metal ion selected from the fourth period transition metal element (Ib) Metal ion selected from the fifth period transition metal element (Ic) Platinum ion or gold ion [2] Following the step [1], the suspension While adjusting the temperature of the suspension A to 15 to 40 ° C., 200 to 100000 parts by mass of metal particles having an average particle diameter of 1 to 20 nm selected from the following (IIa) to (IId) are added to 100 parts by mass of the carrier substance. And mixing to prepare a precursor dispersion of the metal particle-supported catalyst.
(IIa) Metal particles selected from fourth period transition metal elements (IIb) Metal particles selected from fifth period transition metal elements (IIc) Platinum particles or gold particles (IId) At least selected from (IIa) to (IIc) Metal particles formed by combining two or more metals [3] Subsequent to the step [2], in order to remove metal ions not supported on the support material, a precursor dispersion of the metal particle-supported catalyst is used. A step of obtaining a metal particle-supported catalyst dispersion by desalting.
[4] The metal particle-supported catalyst dispersion obtained in the step [3] is dried at a temperature of 100 to 200 ° C. to obtain a metal particle-supported catalyst having a coating layer of metal particles having a thickness of 1 to 50 nm. Process.
According to this manufacturing method, a high temperature treatment step at 100 ° C. or higher is not required other than the drying treatment step, and the operation is easy.

  In the second invention, the amount of metal ions supported on the carrier material after the desalting treatment in the step [3] is 0.001 to 10 parts by mass with respect to 100 parts by mass of the carrier material. It is characterized by. By separating unadsorbed metal ions by the solid-liquid separation treatment, it is possible to suppress a decrease in catalytic reaction and a decrease in electrical characteristics.

The third invention relates the relationship between the mass of the metal ions supported on the carrier material in the step [1] and the mass of the metal particles added to the suspension A in the step [2]. The value of the formula expressed by the following formula (1) is in the range of 0.0001 to 0.005.
Mass of metal ion / (mass of metal ion + mass of metal colloid) (1)
The preferred values of the loading amount of metal ions and the addition amount of metal particles are defined.

  The fourth invention is characterized in that the drying process of the step [4] is performed in an inert atmosphere. It defines a suitable atmosphere when performing the drying process.

In a fifth aspect of the invention, the fourth periodic transition metal element is an element selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, and Cu, and the fifth periodic transition metal element is Zr. characterized Nb, Mo, Tc, Ru, Rh, that is an element selected from the group consisting of P d and Ag.
Specifically, if the supported metal of the metal particles supported catalyst is more produced in the present invention are those selected from these metals, in a loading amount of same level as in the conventional metal particles supported catalyst, more excellent It is possible to show the catalyst performance.

6th invention is characterized by the ratio of the metal particle contained in the said metal particle carrying catalyst being 40-99.9 mass%. The present invention specifies the content of the supported metal in the metal particle-supported catalyst, and in particular, compared with the conventional metal particle-supported catalyst, even if the amount of supported metal is small, It is possible to show catalyst performance equal to or higher than that.

In a seventh invention, the carrier material is selected from an inorganic carrier material or an organic carrier material, and the inorganic carrier material or the organic carrier material includes Si, Al, C, Ti, Zr and Ce. It contains at least one element selected from the group consisting of: The present invention defines the type of carrier material in the metal particle-supported catalyst, and can be applied to both inorganic carrier materials and organic carrier materials, and is suitable as an element contained in these carrier materials. Shows the elements.

In an eighth aspect of the present invention, the carrier material is tin oxide, antimony-doped tin oxide (ATO), tin oxide-doped indium oxide (ITO), antimony pentoxide, silicotungstic acid, phosphorus-doped tin oxide (PTO), or aluminum-doped zinc oxide. It contains one or more compounds consisting of (AZO). The present invention defines the type of carrier material in the metal particle-supported catalyst, and can be applied to any of semiconductors, electronic conductors, and proton conductors, and is suitable as a compound contained in these carrier materials. Compound.
Further, a ninth invention is produced by the method for producing a metal particle-supported catalyst according to any one of the first to eighth inventions, wherein the metal particles are made of Ru, Rh, Pd, Ag, Pt and Au. A metal particle-supported catalyst comprising an element selected from the group and used for hydrogenation of unsaturated hydrocarbons or for hydrogenolysis of nitric acids.

  The metal particle-supported catalyst according to the present invention is considered to exhibit a synergistic effect between the metal ions and the metal particles by allowing the metal ions and metal particles supported on the ion exchange site to coexist. Since the particles are supported by forming a coating layer, the catalyst exhibits excellent catalytic performance in terms of, for example, improved activity, extended life, improved gas adsorption ability, and improved electrical characteristics.

  Before describing the specific configuration of the metal particle-supported catalyst or the like according to the embodiment, the basic concept leading to the development of the catalyst will be described. For example, a conventional metal particle-supported catalyst applied to exhaust gas purification uses a support material (for example, alumina or zeolite) and various metal particles called active metals (for example, Pt (platinum), Pd (palladium)). , Cu (copper), etc.) are often carried.

  In such a metal particle-supported catalyst, the amount of the supported metal may be increased for the purpose of improving the catalyst performance. However, it is known that the catalyst performance is saturated when the supported metal is increased beyond a certain level. Such a phenomenon is considered to be caused by the fact that the catalytic action of the supported metal does not sufficiently function due to the aggregation or proximity of the supported metals.

  In addition, those having a carrier particle diameter of nano-order as described in Patent Documents 6 and 7 are difficult to support metal nanoparticles, and a large amount of surface treatment material is used during the synthesis in which metal nanoparticles are aggregated and supported locally. There were problems such as low activity when used.

  When the carrier particle size is nano-order, it is difficult to completely coat the metal nanoparticles, and with the partially coated one, the electrical properties and gas adsorbing capacity are lowered compared to the completely coated one. There was a problem.

  Therefore, the present inventors have conducted intensive studies to solve these problems, and by preliminarily supporting metal ions when the metal is supported on the support material, the loading state / coating state of the metal particles can be determined. In addition to the improvement, it has been found that the synergistic effect of the supported metal ions and metal particles can improve the catalyst performance, the electrical characteristics, and the gas adsorption capacity.

In addition, in the conventional method for producing a metal particle-supported catalyst, for example, a firing step at 500 ° C. or higher, a reduction step in a hydrogen gas atmosphere, and the like are often employed. These processes increase manufacturing costs and increase process control efforts. In this regard, in the method for producing a metal particle-supported catalyst according to the present invention, it is possible to prepare a metal particle-supported catalyst exhibiting excellent catalyst performance without undergoing such steps.
Hereinafter, the metal particle-supported catalyst according to the present invention, the method for producing the metal particle-supported catalyst, and the reaction method will be specifically described.

[Metal particle supported catalyst]
The metal particle-supported catalyst according to the present invention is a metal particle-supported catalyst obtained by supporting metal particles on a carrier material having an ion exchanger and a primary particle diameter of 1 to 500 nm,
(I) carrying one or more metal ions selected from the following (Ia) to (Ic) on the ion exchanger;
(II) carrying metal particles having an average particle diameter of 1 to 20 nm selected from the following (IIa) to (IId) on a carrier substance;
(III) A metal particle-supported catalyst, wherein the metal particles form a coating layer having a thickness of 1 to 50 nm.
(I) (Ia) Metal ion selected from the fourth period transition metal element (Ib) Metal ion selected from the fifth period transition metal element (Ic) Platinum ion or gold ion (II) (IIa) Fourth period transition metal Metal particles selected from elements (IIb) Metal particles selected from fifth period transition metal elements (IIc) Platinum particles or gold particles (IId) (IIa) to (IIc) are combined with at least two kinds of metals. Metal particles

  Conventionally, a metal particle-supported catalyst in which metal particles such as platinum are supported on a support material made of an inorganic material such as zeolite or alumina is known. The metal particle-supported catalyst according to the present invention is obtained by greatly improving the catalyst performance of a conventionally known metal particle-supported catalyst. The characteristics related to the improvement of the catalyst performance are that a predetermined metal ion is supported on the support material and that a metal particle is supported on the support material to form a predetermined coating layer.

(I) Metal ion
The metal particle-supported catalyst according to the present invention needs to carry metal particles using metal ions. Here, the carrying | support of the metal particle using a metal ion means fixing a metal particle to a support | carrier substance on the conditions in which a metal ion exists. Moreover, in the state of the catalyst finally obtained, it means that metal ions and metal particles are immobilized at the ion exchange site of the support material. The metal particle-supported catalyst may support a hydroxide, an oxide, a single metal, a metal complex, or the like derived from a metal ion in the supporting step.

  In the supporting process, the metal ions are supported on the carrier material and show an effect of improving the supporting force with the metal particles supported in the next process (the metal particles are difficult to peel off due to friction, heat, etc.). It is thought that it contributes by the electrical interaction of metal particles. Metal ions are supported by mixing a metal salt solution containing metal ions in a suspension of a carrier material. Further, in this supporting step, by providing a step of removing metal ions that are not adsorbed on the support material, catalyst activity and electrical property deterioration are prevented by the presence of free metal ions. It described in the item regarding the manufacturing method mentioned later. In this way, metal particles supported using metal ions are presumed to exhibit a synergistic effect between metal ions and metal particles, and have high catalytic performance and electrical performance in terms of activity improvement and life extension. It has also been confirmed from experiments described later that it exhibits characteristics and gas adsorption ability.

As the type of the metal ion, one or more metal ions selected from the following (Ia), (Ib) or (Ic) are used.
(Ia) A metal ion selected from the fourth period transition metal elements. Specifically, metal ions selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, and Cu are suitable.
(Ib) A metal ion selected from fifth transition metal elements. Specifically, a metal ion selected from the group consisting of Zr, Nb, Mo, Tc, Ru, Rh, Pd and Ag is preferable.
(Ic) Platinum ion or gold ion.

  A metal particle-supported catalyst that supports metal particles using the metal ions described above has high catalytic performance, electrical characteristics, and gas adsorption capacity in terms of improving activity and extending life due to the synergistic effect of metal ions and metal particles. Can show. As a combination example of metal ions and metal particles, metal ions of the same period, the same genera, and adjacent groups as the supported metal particles are suitable.

  The amount of the metal ions supported on the carrier material is preferably in the range of 0.1 to 100 parts by mass with respect to 100 parts by mass of the carrier material. When the loading amount is within this range, effects such as easy loading of metal particles in the next step are easily exhibited. When the loading amount is less than 0.1 parts by mass, the effect of easily supporting the metal particles in the next step is hardly exhibited, which is not preferable. Moreover, when it exceeds 100 mass parts, many metal salts used as the raw material of a metal ion are carried in after the following process, and it is unpreferable because a metal particle tends to cause aggregation. The amount of the metal ions supported on the support material is more preferably in the range of 0.15 to 90 parts by mass.

(Ii) Metal particles
The metal particle-supported catalyst according to the present invention is one in which metal particles are supported on the surface of a carrier material to form a coating layer. Here, the fact that the metal particles are supported on the carrier material means that the metal particles are immobilized on the surface of the carrier material. The coating layer is formed by densely immobilizing metal particles on the surface of a carrier material.

  The metal particles may be a single metal, a composite metal, or a partial oxide made of a mixture of a single metal and a metal oxide.

As the kind of the metal particles, one or more metal particles selected from the following (IIa), (IIb), and (IIc) are used.
(IIa) Metal particles selected from fourth period transition metal elements. Specifically, metal particles selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni and Cu are suitable.
(IIb) Metal particles selected from fifth period transition metal elements. Specifically, metal particles selected from the group consisting of Zr, Nb, Mo, Tc, Ru, Rh, Pd and Ag are suitable.
(IIc) Platinum particles or gold particles

Such metal particles are supported on a support material and exhibit catalytic action such as hydrogenation reaction, hydrocracking reaction, oxidation reaction or dehydrogenation reaction. As the metal particles exhibiting the action of hydrogenation reaction or hydrogenolysis reaction, Fe, Co, Ni, Nb, Mo, Ru, Rh, Pd, Pt, Au, Cu, or a composite metal thereof is particularly preferable. In addition, as the metal particles exhibiting the action of oxidation reaction or dehydrogenation reaction, Ag, Cu, Pt, Pd, Au, or a composite metal thereof is preferable.
Preferred metals that are effective for electrical characteristics include Ag, Pd, Au, Pt, Cu, Ru, Rh, and composite metals thereof. As the metal effective for the gas adsorption capacity, Ag, Pd, Au, Pt, and a composite metal thereof are preferable.

  The amount of the metal particles supported on the carrier material is preferably in the range of 40 to 99.9% by mass, although the specific gravity / particle diameter of the metal and the specific gravity of the carrier and the particle diameter are in balance based on the mass of the carrier material. Within this range, the metal particles can be coated with a carrier having a thickness of 1 to 50 nm and have excellent catalytic performance, electrical characteristics, and gas adsorbing ability in terms of activity improvement and life extension in terms of excellent support dispersibility. The catalyst performance can be shown. When the loading amount of the metal particles is less than 40% by mass, the carrier particles may not be completely covered with the metal particles. On the other hand, when the loading amount of the metal particles exceeds 99.9% by mass, the carrying dispersibility is poor and the life may be shortened. As a more preferable loading amount of the metal particles in the support material, a range of 45 to 99.8% by mass is recommended.

  The average particle size when the metal particles are supported on a carrier substance is preferably in the range of an average particle size of 1 to 20 nm from the viewpoint of obtaining sufficient activity. It is difficult to obtain metal particles having an average particle diameter of 1 nm or less. Further, when metal particles having an average particle diameter of more than 20 nm are used, the surface area of the particles becomes small, and the catalytic action tends to be reduced. As a more preferable range of the average particle diameter, a range of 1 to 15 nm is recommended. The shape of the metal particles is not particularly limited, and a spherical shape, a chain shape, a bead shape, an irregular shape, an angular shape, or the like is recommended.

(Iii) Metal particle loading state
In the metal particle-supported catalyst according to the present invention, the metal particles are supported on the support surface to form a coating layer (shell layer). When the metal particles are present alone without forming a coating layer or only partially formed with a coating layer, the catalytic activity may be lowered or the electrical characteristics may be lowered.

  In the present application, among all the supported metal particles, the supported state is the primary before and after the support with a scanning electron microscope (for example, S-5500 manufactured by Hitachi, Ltd. in the examples and comparative examples described later). The thickness of the coating layer can be calculated by measuring the particle diameter. It is also possible to confirm the presence of partial coating and free metal particles that are not supported.

  In the present application, all the supported metal particles are preferably a single metal or a composite metal, but may be partially oxidized. The presence or absence of oxidation can be confirmed by an X-ray diffraction method. If no single metal or composite metal particles are present at all, it may cause a significant decrease in activity or a short life.

(Iv) Carrier material
As the carrier material of the metal particle-supported catalyst according to the present invention, a known carrier material can be used. Specifically, a material selected from an inorganic carrier material or an organic carrier material can be used. As such a carrier material, those containing at least one selected from the group consisting of Si, Al, C, Ti, Zr and Ce are preferably used. Examples of such carrier materials include silica, zeolite, alumina, carbon black, activated carbon, titania, zirconia or ceria. In the present application, these carrier materials include carrier materials corresponding to the following a) to e). Of these carrier materials, carbon black and activated carbon correspond to organic carrier materials, and the remaining carrier materials correspond to inorganic carrier materials.

a) Support materials obtained by substituting some of the constituent elements of these support materials with other elements.
b) Carrier materials obtained by substituting elements or compounds usually contained in these carrier materials with other elements or compounds.
c) Carrier materials obtained by inserting other elements or compounds into these carrier materials.
d) Carrier materials obtained by subjecting these carrier materials to chemical treatment and modification.
e) Carrier materials obtained by subjecting these carrier materials to hydrothermal treatment.
The specific surface area, pore volume or pore distribution of the support material is not particularly limited and may be appropriately selected according to the use of the metal particle-supported catalyst. Each of the substances listed above also functions as an ion exchanger having an ion exchange site.

Further, as the carrier material of the metal particle-supported catalyst according to the present invention, a carrier material such as a semiconductor, an electronic conductor, or a proton conductor can be used. Specifically, carriers such as tin oxide, antimony-doped tin oxide (ATO), tin oxide-doped indium oxide (ITO), antimony pentoxide, silicotungstic acid, phosphorus-doped tin oxide (PTO), aluminum-doped zinc oxide (AZO), etc. Those selected from substances or organic carrier substances can be used. Such a carrier material can be used as a catalyst for a fuel cell electrode, a catalyst for a gas sensor such as hydrogen, oxygen, CO, and CO ₂ that requires an electrical function.

[Reaction system using metal particle supported catalyst]
The metal particle supported catalyst according to the present invention can be used as a catalyst in various reactions. In particular, it can be suitably used for the following reactions 1) to 4).
1) Hydrogenation reaction of unsaturated hydrocarbons, aromatics, esters, aldehydes, ketones,
2) Oxidation reaction of alcohols, methylene, diesel automobile exhaust gas, gasoline automobile exhaust gas,
3) Dehydrogenation reactions of gasoline, saturated hydrocarbons, unsaturated hydrocarbons, aromatics,
4) Hydrogenolysis reaction of nitric acids and sulfuric acids such as gasoline, benzoyl group derivatives, epoxy derivatives,
5) Gas sensor calculated from electrical changes due to adsorption of hydrogen gas, oxygen gas, CO, CO ₂ gas 6) DMFC (Direct-Methanol Fuel Cell), PEFC (Polymer) Electrolyte Fuel Cell) Fuel cell power generation system.

The shape of the catalyst may be a powder, a molded body (granular, square, four-leaf, etc.), a honeycomb, or the like. When obtaining a molded body or a honeycomb, a binder component may be used. The binder component is not particularly limited as long as it does not negatively influence the reaction. Moreover, you may dry and bake as needed.
The reaction system may be a batch system, a column system (continuous system), or a gas phase reaction, a liquid phase reaction, or a gas phase-liquid phase reaction depending on the purpose.

[Method for producing metal particle-supported catalyst]
The method for producing a metal particle-supported catalyst according to the present invention includes the following steps [1] to [4]. The method for producing a metal particle-supported catalyst (hereinafter referred to as “first method” for convenience). It may be referred to as a “production method”).
[1] The following (Ia) to (Ic) are selected from the following (Ia) to (Ic) for a first suspension in which a carrier material containing an ion exchanger (where the average particle size of primary particles is 1 to 500 nm) is dispersed in a solvent. One or more kinds of metal ions are added at a ratio of 0.1 to 100 parts by mass in terms of metal elements with respect to 100 parts by mass of the carrier substance, and the metal ions are carried by the carrier substance to prepare suspension A. Process.
(Ia) Metal ion selected from the fourth period transition metal elements
(Ib) A metal ion selected from fifth transition metal elements
(Ic) Platinum ion or gold ion
[2] Subsequent to the step [1], while adjusting the temperature of the suspension A to 15 to 40 ° C., metal particles having an average particle diameter of 1 to 20 nm selected from the following (IIa) to (IId): A step of adding 50 to 100,000 parts by mass with respect to 100 parts by mass of the carrier substance and mixing them to prepare a precursor dispersion of the metal particle-supported catalyst.
(IIa) Metal particles selected from fourth transition metal elements
(IIb) Metal particles selected from fifth transition metal elements
(IIc) Platinum particles or gold particles
(IId) Metal particles formed by combining at least two metals selected from (IIa) to (IIc)
[3] Subsequent to the step [2], in order to remove the metal ions not supported on the support material, the metal particle-supported catalyst precursor dispersion is desalted to obtain a metal particle-supported catalyst dispersion. Obtaining step.
[4] A step of drying the metal particle-supported catalyst dispersion obtained in the step [3] at a temperature of 100 to 200 ° C.

In addition to the above manufacturing method, when the metal particles are supported on a carrier material on which metal ions are previously supported, the following manufacturing method (hereinafter, this manufacturing method may be referred to as “second manufacturing method” for convenience). May be adopted.
That is, a support material having a primary particle diameter of 1 to 500 nm including an ion exchanger on which one or more metal ions selected from (Ia) to (Ic) of (I) below are supported, A method for producing a metal particle-supported catalyst, comprising a step of forming a coating layer having a thickness of 1 to 50 nm with metal particles having an average particle diameter of 1 to 20 nm selected from IIa) to (IId).
(I) (Ia) Metal ion selected from the fourth period transition metal element (Ib) Metal ion selected from the fifth period transition metal element (Ic) Platinum ion or gold ion (II) (IIa) Fourth period transition metal Metal particles selected from elements (IIb) Metal particles selected from fifth period transition metal elements (IIc) Platinum particles or gold particles (IId) (IIa) to (IIc) are combined with at least two kinds of metals. Metal particles

The first manufacturing method will be described below.
(I) Process [1]
In this step, one or more metals selected from the following (Ia) to (Ic) are added to a first suspension in which a carrier material having an ion exchanger having a primary particle size of 1 to 500 nm is dispersed in a solvent. Ions are added and supported at a ratio of 0.1 to 100 parts by mass in terms of metal elements with respect to 100 parts by mass of the carrier substance, and the suspension (in this application, this suspension is referred to as “suspension A” for convenience. To prepare).
(Ia) Metal ion selected from the fourth period transition metal element (Ib) Metal ion selected from the fifth period transition metal element (Ic) Platinum ion or gold ion

  The carrier material used in the present invention is as described above. In the present invention, the carrier substance is usually used in a state suspended in water. The first suspension which is a suspension of such a carrier material is, for example, oxide fine particles obtained by hydrothermal treatment of metal hydroxide or oxide fine particles obtained by firing metal hydroxide. It is obtained by suspending a carrier material obtained by breaking down powder with alumina beads or the like in water. The amount of water used is preferably 100 to 99,900 parts by weight, more preferably 400 to 19,900 parts by weight with respect to 100 parts by weight of the carrier substance. The first suspension thus obtained may be further diluted with water as necessary, or may be concentrated by decantation. As the dilution water, deionized water is preferred. The concentration of the first suspension after dilution is preferably 0.1 to 50% by mass.

Next, metal ions are added to the suspension of carrier material. The metal ion is an ion of at least one metal selected from the group consisting of a fourth period transition metal element, a fifth period transition metal element metal element, platinum, and gold.
The fourth periodic transition metal element is preferably an element selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni and Cu, and the fifth periodic transition metal element is Zr, Nb, An element selected from the group consisting of Mo, Tc, Ru, Rh, Pd and Ag is preferable.

  The addition amount of metal ions is preferably 0.1 to 100 parts by mass, more preferably 0.2 to 80 parts by mass in terms of metal element with respect to 100 parts by mass of the carrier substance. If the added amount of metal ions is in this range, ion exchange at the ion exchange site of the carrier material and adsorption onto the carrier surface are facilitated, and a synergistic effect when supported together with metal particles is easily exhibited. . When the addition amount is less than 0.1 parts by mass, ion exchange and adsorption to the carrier become difficult, and a synergistic effect with metal particles hardly occurs. When the added amount exceeds 100 parts by mass, the effect of removing unsupported metal ions in the subsequent desalting step becomes insufficient, and there is a problem that highly dispersed loading cannot be performed in the metal particle loading step.

  As a method of adding the amount of metal ions in the above range to the first suspension, 1) a method of adding a predetermined solution containing the amount of metal ions in the above range in terms of metal element, and 2) metal element A method of adding a metal compound in an amount capable of forming the above-mentioned proportion of metal ions in terms of conversion and generating metal ions in this suspension can be mentioned.

  In the method 1), a solution containing metal ions can be prepared by dissolving a metal compound capable of forming metal ions in a solvent. The valence of the metal ion is not particularly limited.

  The compound capable of generating a metal ion is not particularly limited as long as it forms a metal ion in the suspension. Examples of the compound that forms a Pd ion include palladium chloride, palladium nitrate, and palladium sulfate. , Palladium citrate, palladium acetate and the like. These palladium compounds can be used alone or in combination of two or more.

An example of a compound capable of generating other metal ions is described below.
Copper ion: Copper chloride, copper sulfate, copper nitrate
Platinum ions: chloroplatinic acid, potassium chloroplatinum (IV), sodium chloroplatinum (IV), potassium tetranitroplatinum (II), sodium hexahydroxoplatinum (IV) hydrate, dinitrodiammine platinum nitrate, dinitrodiammine platinum Ammonia and tetraamminedichloroplatinum hydrate Gold ions: chloroauric acid, sodium gold sulfite, potassium gold cyanide and sodium gold cyanide
Silver ion: Silver nitrate, Silver sulfate,
Iron ion: ferric sulfate, ferrous acetate
Nickel ion: Nickel sulfate, nickel nitrate, nickel chloride
Cobalt ion: Cobalt sulfate, cobalt nitrate, cobalt chloride
Cerium ions: cerium nitrate, cerium chloride, cerium sulfate
The metal compound that generates metal ions is usually dissolved in a solvent and added to the first suspension.

The solvent used for the solution containing a metal ion is not limited to a specific solvent as long as it does not show reactivity with the metal and can dissolve the metal compound. Such solvents include
water;
Alcohols such as methanol, ethanol, isopropanol, n-butanol, methyl isocarbinol;
Ketones such as acetone, 2-butanone, ethyl amyl ketone, diacetone alcohol, isophorone, cyclohexanone;
Amides such as N, N-dimethylformamide and N, N-dimethylacetamide;
Ethers such as diethyl ether, isopropyl ether, tetrahydrofuran, 1,4-dioxane, 3,4-dihydro-2H-pyran;
Glycol ethers such as 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, ethylene glycol dimethyl ether;
Glycol ether acetates such as 2-methoxyethyl acetate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate;
Esters such as methyl acetate, ethyl acetate, isobutyl acetate, amyl acetate, ethyl lactate, ethylene carbonate;
Aromatic hydrocarbons such as benzene, toluene, xylene;
Aliphatic hydrocarbons such as hexane, heptane, iso-octane, cyclohexane;
Halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, dichloropropane, chlorobenzene;
Sulfoxides such as dimethyl sulfoxide;
Pyrrolidones such as N-methyl-2-pyrrolidone and N-octyl-2-pyrrolidone;
Examples include glycols such as ethylene glycol, propylene glycol, and hexylene glycol.

The method 2) is a method in which the metal compound described in the method 1) is added to the first suspension as it is.
In the case of producing a metal particle-supported catalyst in which the metal particles are composite metal particles, in the method 1), a solution obtained by dissolving two or more metal compounds in a solvent is used as the first suspension. What is necessary is just to add to a liquid, and what is necessary is just to add 2 or more types of metal compounds to a said 1st suspension in the method of said 2).

  Although the temperature at the time of adding the solution or metal compound containing a metal ion to a 1st suspension liquid is not specifically limited, The range of 15-40 degreeC is preferable. If the addition temperature is lower than the above range, the metal ions may not be sufficiently supported, and if the addition temperature is higher than the above range, further improvement in the support efficiency will not be seen, which is economically undesirable.

Further, after the addition, it is preferable that the suspension A is stirred and sufficiently mixed while maintaining the temperature within the above range. Stirring is preferably carried out at 15 to 40 ° C. for usually 5 minutes or longer, preferably 10 minutes or longer. If necessary, the stirring may be performed for up to about 3 hours, preferably up to about 1 hour.
In particular, when a solid metal compound is added, it is necessary to sufficiently perform an operation such as stirring until the metal compound is sufficiently dissolved and metal ions are generated.

(Ii) Step [2]
While the temperature of the suspension A obtained in the step [1] is adjusted to 15 to 40 ° C., metal particles having an average particle diameter of 1 to 20 nm selected from the following (IIa) to (IId) are added to the carrier substance 100. A precursor dispersion of a metal particle-supported catalyst is prepared by adding and mixing 200 to 100,000 parts by mass with respect to parts by mass.
(IIa) Metal particles selected from fourth transition metal elements
(IIb) Metal particles selected from fifth transition metal elements
(IIc) Platinum particles or gold particles
(IId) Metal particles formed by combining at least two metals selected from (IIa) to (IIc)

  In this step, the metal particles are usually added to the suspension obtained in the previous step as a metal colloid solution. Although the preparation method of such a metal colloid solution is well-known, the method described in each Example of Unexamined-Japanese-Patent No. 2002-180110 (applicant = JGC Catalysts and Chemicals) can be mentioned, for example.

In practice, the metal concentration of the metal colloid solution is preferably in the range of 1 to 20% by mass. The metal colloid solution is preferably added in an amount of 200 to 100,000 parts by mass in terms of metal particles with respect to 100 parts by mass of the carrier substance. Within this range, the metal particles can be coated with a carrier having a thickness of 1 to 50 nm and have excellent catalytic performance, electrical characteristics, and gas adsorbing ability in terms of activity improvement and life extension in terms of excellent support dispersibility. The catalyst performance can be shown. When the addition amount of the metal particles is less than 200 parts by mass, the carrier particles may not be completely covered with the metal particles. Also, if the amount of the metal particles exceeds 100000 parts by mass, poor carrier dispersibility, disadvantages in that it may life become shorter accordingly.

  The temperature when adding and mixing the metal colloid solution is preferably 15 to 40 ° C. If it is less than 15 degreeC, a metal particle may not fully be supported, and practicality may fall. If it exceeds 40 ° C., further improvement of the supporting effect is not recognized, which is economically undesirable.

  In the mixing, it is desirable to perform stirring for usually 5 minutes or more, preferably 10 minutes or more, and if necessary, stirring may be performed for usually up to about 3 hours, preferably up to about 1 hour.

(Iii) Step [3]
In step [3], the metal particle-supported catalyst precursor dispersion obtained in step [2] is desalted by separating the solid and the liquid in order to remove metal ions not supported on the support material. To obtain a metal particle-supported catalyst dispersion.

  The desalting method is not particularly limited. For example, a method of removing metal ions from a precursor particle dispersion of a metal particle-supported catalyst using an ion exchange resin, or a method of removing metal ions by performing solid-liquid separation on an outer membrane. And a method of extracting a solution containing metal ions by solvent extraction.

  The concentration of the metal particle-supported catalyst dispersion obtained by desalting is preferably 0.1 to 70% by mass, and more preferably 1 to 50% by mass. When the concentration of the suspension is less than 0.1%, productivity is poor and this is not economically preferable. When it exceeds 70%, the dispersibility of the suspension is poor, and when the metal particles are supported in the next step, a carrier on which the metal particles are not supported is generated, which is not preferable.

  The supported amount of metal ions ion-exchanged or adsorbed on the support material is preferably 0.001 to 10 parts by mass with respect to 100 parts by mass of the support material. When the supported amount of the metal ions adsorbed on the support material is less than 0.001 with respect to 100 parts by mass of the support material, the interaction between the metal ions and the metal particles is insufficient and the support force is weak. The metal particle coating layer may fall off. If it exceeds 10 parts by mass, it may elute into the system when using a catalytic reaction, which may cause a decrease in activity and a decrease in electrical characteristics.

The relationship between the mass of the metal ions supported on the carrier material in the step [1] and the mass of the metal particles added to the first suspension in the step [2] is as follows ( 2) When expressed by the formula, the value of the formula is preferably in the range of 0.0001 to 0.005.
Mass of metal ion / (mass of metal ion + mass of metal particle) (2)

  In this method, it is considered that the metal particles are arranged without gaps and form a coating layer by supporting the metal particles in a state where metal ions are ion-exchanged or adsorbed on the support material. It can be said that the formation of such a coating layer enhances the supporting force of the metal particles. In addition to these characteristics, the catalytic performance is improved from the viewpoint of improving the activity and extending the life due to the synergistic effect of the metal ions and the metal particles. The above equation (2) indicates the ratio of the mass of metal ions to the total metal mass (total of metal ion mass and metal particle mass) supported on the metal particle supported catalyst. For this reason, when the value of the formula (2) is less than 0.0001, it is difficult to obtain the effect of improving the dispersibility of the metal particles and the effect of improving the supporting force, whereas when this value exceeds 0.005, the metal There is a possibility that the loading ratio of the particles becomes low and the activity of the catalyst is lowered.

(Iv) Step [4]
The metal particle-supported catalyst dispersion obtained in the above step [3] (or the metal particle-supported catalyst after separation if solid-liquid separation has already been performed) is dried at 100 to 200 ° C. to obtain a metal particle-supported catalyst. Can be obtained. About drying time, it is desirable to dry at the temperature of 100-200 degreeC for 1 to 20 hours. About a drying temperature range, the range of 100-150 degreeC is recommended more suitably.

When the drying temperature is less than 100 ° C., drying tends to take time and economical efficiency tends to be poor. When the drying temperature exceeds 200 ° C., there is a problem in that particle sintering and oxidation progress.
It is preferable to perform the said drying process in air | atmosphere or inert atmosphere. More preferable examples of the dry atmosphere include an inert atmosphere. Examples of the inert atmosphere include nitrogen, hydrogen, argon, and the like.

  The metal particle-supported catalyst according to the present invention is capable of coating metal particles after ion-exchange or adsorption of metal ions on a support material and then supporting the metal particles and increasing the support ability of the metal particles. As a result, it is possible to surpass the dispersed state of the metal particles found in the catalyst supporting the metal particles by the conventional method. Further, by providing a step of ion exchange or removal of metal ions that are not adsorbed, the loss of metal ions can be reduced when the catalyst is used, and it is possible to prevent a decrease in catalytic activity and a decrease in electrical characteristics.

In the metal particle-supported catalyst according to the present invention, the metal particle-supported catalyst according to the present invention is a conventional metal particle because the surface of the metal particle contributes to the catalytic action more effectively by coating the metal particle on the carrier. Even if the amount of metal supported is the same as that of the supported catalyst, high catalyst performance, electrical characteristics, and gas adsorption ability can be exhibited from the viewpoint of improving activity and extending life.
In addition, metal ions supported on the ion exchange site of the support material have a synergistic effect between the metal ions and the metal particles, and in this respect as well, high catalyst performance, electrical characteristics, Adsorption ability can be shown.

  In this way, by improving the activity of the catalyst and extending the life of the catalyst, in applications where the catalyst performance equivalent to that of the conventional metal particle-supported catalyst is sufficient, the metal having a smaller amount of metal particles supported than the conventional metal particle-supported catalyst. Since a particle-supported catalyst can be used, resources are saved. In particular, when expensive metal particles such as Pd or Pt are used, this contributes to a reduction in manufacturing cost.

  Furthermore, since the support material carrying the metal ions and the metal particles is dried at a temperature range of 100 to 200 ° C., the metal particle-supported catalyst is obtained. For example, a calcination step at 500 ° C. or higher or reduction in a hydrogen gas atmosphere Compared to the case where a process or the like is required, it is possible to prepare a metal particle-supported catalyst under practical conditions while suppressing an increase in manufacturing cost and labor of process control.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples at all.
[Measuring method]
The measurement method employed in the present application is described below.
[1] Measurement of dispersion state of metal particles The sample before and after supporting the metal particles was photographed with a scanning electron microscope (manufactured by Hitachi, Ltd., S-5500) at a magnification of 300 to 1,000,000 times. In the obtained photographic projection, the thickness of the coated metal particles was determined from the front and rear particle sizes. In addition, the presence of uncovered / aggregated portions and unsupported metal particles were examined from the particle loading state.

[2] Composition analysis of metal particles and metal ions supported on a catalyst A catalyst supporting metal ions and metal particles (including composite metal particles) as a sample is calcined at 600 ° C., and the calcined sample is obtained. It melted with an alkali melting agent. Thereafter, the melt is dissolved in a 28% by mass hydrochloric acid solution, and the solution is diluted with pure water, and then included in the metal particle-supported catalyst with an ICP inductively coupled plasma emission spectrometer SPS1200A (Seiko Electronics Co., Ltd.). The amount of element to be measured was measured.

[3] Catalyst performance evaluation
In Examples and Comparative Examples described later, each of Pd, Pt, Ru, Rh, Ag, Pt—Rh composite metal, Pd—Au composite metal, Pd—Pt composite metal, Pt—Ru composite metal, and Pt—Cu composite metal. A metal particle supported catalyst carrying metal particles was prepared. Among these, (1) hydrogenation reaction of acetylene and (2) decomposition reaction of nitrate ion were evaluated for the catalyst supporting Pd (including the case of supporting a Pd composite metal).

(1) Hydrogenation reaction of acetylene
In the hydrogenation reaction of acetylene, a reaction tube φ21 mm (double tube glass reaction tube) is filled with 0.002 g of metal particle supported catalyst in terms of metal particles. Hot water is circulated around the outer periphery of the reaction tube to keep the catalyst layer at a constant temperature (40 ° C.). After introducing a reaction gas (C ₂ H ₂ ; 12 ml / min), a reducing gas (H ₂ ; 10 ml / min) and a carrier gas (N ₂ ; 400 ml / min), the gas after 80 minutes was collected and subjected to gas chromatography. Thus, the production rate of ethylene and ethane relative to the amount of the supplied reaction gas (((C ₂ H ₄ + C ₂ H ₆ ) / C ₂ H ₂ ) × 100 [mol%]) was determined.

(2) Nitrate ion decomposition reaction (hydrogenolysis reaction)
200 g of a sodium nitrate solution having a nitrate ion concentration of 4.5 mol / L is placed in a 1 L separable flask. Thereafter, a catalyst supporting metal particles in an amount of 0.02 g in terms of metal particles was added to the catalyst, and the mixture was stirred with a magnetic stirrer under an argon purge, and the temperature was adjusted to 80 ° C. Thereafter, 1.2 mol of hydrazine was added over 3 hours, and the nitrate ion concentration after the addition was measured and calculated by spectrophotometry. The conversion rate of nitrate ions at that time ((initial nitrate ion concentration−nitrate ion concentration after completion of reaction) / (initial nitrate ion concentration) × 100 [mol%]) was evaluated as the catalytic activity.
Each of the following examples satisfies the requirements of the claims.

(3) Electrical characteristics
10 g of a metal particle-supported catalyst is compressed at a pressure of 100 kg / cm ² to form pellets, and the resistance values are measured with a tester at both ends thereof. From the pellet thickness, cross-sectional area, and resistance value, the specific resistance value [Ω · cm ] ((Resistance value [Ω] × pellet cross-sectional area [cm ² ]) / (pellet thickness [cm])).
Each of the following examples satisfies the requirements of the claims.

[Carrier Material Preparation Example A]
Preparation of silica suspension (first suspension)
Silica sol (manufactured by JGC Catalysts & Chemicals Co., Ltd., trade name: Cataloid SI-550, primary particle size: 5 nm, solid content concentration: 20%) is removed using an amphoteric ion exchange resin (trade name: SMNUPB, manufactured by Mitsubishi Chemical Corporation). Salt was added to prepare an aqueous dispersion (A) having a concentration of 20% by mass.

[Carrier Material Preparation Example B]
Preparation of ATO suspension (first suspension)
Antimony-doped tin oxide (ATO) fine particle dispersion (manufactured by JGC Catalysts & Chemicals Co., Ltd., trade name: ELCOM V-3501, primary particle size: 8 nm, solid content concentration: 20%, modified alcohol dispersion) is diluted with pure water, An aqueous dispersion (B) having a concentration of 5% by mass was prepared.

[Carrier Material Preparation Example C]
Preparation of ITO suspension (first suspension)
Tin-doped indium oxide (ITO) fine particle dispersion (manufactured by JGC Catalysts and Chemicals, trade name: ELCOM V-2504, primary particle size: 20 nm, solid content concentration: 20% 2-propanol dispersion) is diluted with pure water, An aqueous dispersion (C) having a concentration of 5% by mass was prepared.

[Carrier Material Preparation Example D]
Preparation of PTO suspension (first suspension)
Phosphorus-doped tin oxide (PTO) powder (manufactured by JGC Catalysts & Chemicals, trade name: ELCOM TL-30S, primary particle size: 30 nm, solid content concentration: 20%, 2-propanol dispersion) is diluted with pure water and KOH, A diluted solution having a concentration of 25% by mass and pH 11 was prepared. After that, using 0.15 mm quartz beads for 120 minutes of breaking down, centrifuging at 8000 G for 10 minutes, and then desalting with amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) A 10% PTO dispersion (D) was obtained. It was 30 nm when the primary particle diameter of the obtained dispersion liquid was measured with the scanning electron microscope.

[Carrier Material Preparation Example E]
Preparation of Sb ₂ O ₅ suspension (first suspension)
Antimony pentoxide fine particle dispersion (manufactured by JGC Catalysts & Chemicals Co., Ltd., trade name: ELCOM V-4502, primary particle size: 30 nm, solid content concentration: 20% modified alcohol dispersion) is diluted with pure water, and the concentration is 5% by mass. An aqueous dispersion (E) was prepared.

[Carrier Material Preparation Example F]
Preparation of SnO ₂ suspension (first suspension)
Tin oxide powder (manufactured by Showa Processing Co., Ltd.) was diluted with pure water and KOH to prepare a diluted solution having a concentration of 25% by mass and pH 11. After that, using 0.15 mm quartz beads for 120 minutes of breaking down, centrifuging at 8000 G for 10 minutes, and then desalting with amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) A 5% SnO ₂ dispersion (F) was obtained. It was 20 nm when the primary particle diameter of the obtained dispersion liquid was measured with the scanning electron microscope.

[Carrier Material Preparation Example G]
Preparation of Al ₂ O ₃ suspension (first suspension)
Aluminum hydroxide oxide powder (manufactured by JGC Catalysts & Chemicals Co., Ltd., trade name: Cataloid AP-3, primary particle size: 20 nm, solid content concentration: 75% powder) is diluted with pure water and stirred with a magnetic stirrer for 30 minutes. An Al ₂ O ₃ suspension (dispersion (G)) having a concentration of 1% by mass was prepared. It was 20 nm when the primary particle diameter of the obtained dispersion liquid was measured with the scanning electron microscope.

[Carrier Material Preparation Example H]
Preparation of activated alumina suspension (first suspension)
Activated alumina (Wako Pure Chemical Industries, Ltd., model number: 596-15865, specific surface area 250 m ² / g, particle diameter 50 μm, γ-alumina) was dispersed in pure water to prepare an aqueous dispersion having a concentration of 20% by mass. After that, it is crushed for 240 minutes by breaking down using 0.15 mm of quartz beads, centrifuged at 8000 G for 10 minutes, and then desalted using amphoteric ion exchange resin (product name: SMNUPB, manufactured by Mitsubishi Chemical Corporation) A 10% γ-alumina dispersion (H) was obtained. It was 50 nm when the primary particle diameter of the obtained dispersion liquid was measured with the scanning electron microscope.

[Carrier Material Preparation Example I]
Preparation of carbon black (CB) suspension (first suspension)
Carbon black (manufactured by Ketjen Black International Co., Ltd., trade name: Ketjen Black EC, surface area 800 m ² / g, oil absorption 360 g / 100 g) is dispersed in pure water, subjected to boiling treatment for 1 hour, and the concentration is 10% by mass. An aqueous dispersion was prepared. After that, it is crushed for 240 minutes by breaking down using 0.15 mm of quartz beads, centrifuged at 8000 G for 10 minutes, and then desalted using amphoteric ion exchange resin (product name: SMNUPB, manufactured by Mitsubishi Chemical Corporation) A 5% CB dispersion (I) was obtained. It was 80 nm when the primary particle diameter of the obtained dispersion liquid was measured with the scanning electron microscope.

[Metal Particle Preparation Example 1]
Synthesis of Pd particle dispersion
A solution was prepared by dissolving 122 g of ferrous sulfate as a reducing agent in 219 g of an aqueous citric acid solution (concentration: 30% by mass). Then, 341 g of this solution was added to 39 g of an aqueous palladium nitrate solution (concentration 20% by mass) at room temperature, and thoroughly mixed to prepare a dispersion of Pd particles. Washing and desalting was performed using an ultrafilter (manufactured by ADVANTEC, Ultrafilter Q0500), followed by concentration to obtain a Pd colloid solution (1) having a Pd equivalent concentration of 3%. When the particle diameter of the obtained Pd colloid was measured with a scanning electron microscope (manufactured by Hitachi, Ltd., S-5500), the average particle diameter was 3 nm.

[Metal Particle Adjustment Example 2]
Synthesis of Pt particle dispersion
A metal salt aqueous solution obtained by dissolving 25 g of chloroplatinic acid hexahydrate (9 g in terms of platinum metal) in 16,000 g of pure water was added to an aqueous solution of trisodium citrate having a concentration of 5.0% by weight as a complexing stabilizer. , 660 g and a sodium borohydride aqueous solution 140 g having a concentration of 0.1% by weight as a reducing agent were added and stirred and mixed at 20 ° C. in a nitrogen atmosphere to obtain a platinum colloid solution in which platinum fine particles were dispersed in water. . Subsequently, the platinum colloid solution was washed and desalted using an ultrafilter (manufactured by ADVANTEC, Ultrafilter Q0500), and concentrated to obtain a platinum colloid solution (2) having a concentration of 3.0% by weight in terms of platinum metal. When the particle diameter of the obtained Pt colloid was measured with a scanning electron microscope (manufactured by Hitachi, Ltd., S-5500), the average particle diameter was 1 nm.

[Metal Particle Preparation Example 3]
Synthesis of Ru particle dispersion
In a metal salt aqueous solution obtained by dissolving 23.3 g of ruthenium (III) chloride trihydrate (9 g in terms of ruthenium metal) in 16,000 g of pure water, citric acid having a concentration of 5.0% by weight as a complexing stabilizer A ruthenium colloid formed by adding 1,660 g of a trisodium aqueous solution and 140 g of a sodium borohydride aqueous solution having a concentration of 0.1% by weight as a reducing agent and stirring and mixing at 20 ° C. in a nitrogen atmosphere to disperse ruthenium fine particles in water. A solution was obtained. Subsequently, the ruthenium colloid solution was washed and desalted using an ultrafilter (manufactured by ADVANTEC, Ultrafilter Q0500) and concentrated to obtain a ruthenium colloid solution (3) having a concentration of 3.0% by weight in terms of ruthenium metal. When the particle diameter of the obtained Pt colloid was measured with a scanning electron microscope (manufactured by Hitachi, Ltd., S-5500), the average particle diameter was 2 nm.

[Metal Particle Preparation Example 4]
Synthesis of Rh particle dispersion
In a metal salt aqueous solution obtained by dissolving 23.3 g of rhodium (III) chloride trihydrate (9 g in terms of rhodium metal) in 100 g of pure water, citric acid (Kanto) having a concentration of 5.0% by weight as a complexing stabilizer. (Chemical) 50 g of an aqueous solution and 900 g of monoethylene glycol as a solvent were added and stirred and mixed at 100 ° C. for 6 hours in a nitrogen atmosphere to obtain a rhodium colloid solution in which rhodium fine particles were dispersed. Subsequently, the rhodium colloid solution was concentrated by a rotary evaporator to obtain a rhodium colloid solution (4) having a concentration of 3.0% by weight in terms of rhodium metal. When the particle diameter of the obtained rhodium colloid was measured with a scanning electron microscope (manufactured by Hitachi, Ltd., S-5500), the average particle diameter was 3 nm.

[Metal Particle Adjustment Example 5]
Synthesis of Ag particle dispersion
A solution was prepared by dissolving 122 g of ferrous sulfate as a reducing agent in 219 g of a sodium citrate aqueous solution (concentration: 30% by mass). Then, 341 g of this solution was added to 80 g of an aqueous silver nitrate solution (concentration: 10% by mass) at room temperature, and thoroughly mixed to prepare a dispersion of Pd particles. Washing and desalting was carried out using an ultrafilter (manufactured by ADVANTEC, Ultrafilter Q0500), followed by concentration to obtain an Ag colloid solution (5) having an Ag equivalent concentration of 3%. When the particle diameter of the obtained Ag colloid was measured with a scanning electron microscope (manufactured by Hitachi, Ltd., S-5500), the average particle diameter was 10 nm.

[Metal Particle Preparation Example 6]
Synthesis of Pt-Rh particle dispersion
To a metal salt aqueous solution obtained by dissolving 23.3 g of rhodium (III) chloride trihydrate (9 g in terms of rhodium metal) and 25 g of chloroplatinic acid hexahydrate (9 g in terms of platinum metal) in 100 g of pure water, 100 g of citric acid (manufactured by Kanto Chemical) with a concentration of 5.0% by weight as a complexing stabilizer and 1800 g of monoethylene glycol as a solvent are added, and the mixture is stirred and mixed at 100 ° C. for 6 hours in a nitrogen atmosphere. A platinum-rhodium colloidal solution in which was dispersed was obtained. Next, the platinum-rhodium colloid solution was concentrated with a rotary evaporator to obtain a platinum-rhodium colloid solution (6) having a concentration of 3.0% by weight in terms of platinum-rhodium metal. When the particle diameter of the obtained platinum-rhodium colloid was measured with a scanning electron microscope (manufactured by Hitachi, Ltd., S-5500), the average particle diameter was 2 nm.

[Metal Particle Preparation Example 7]
Synthesis of Pd-Au particle dispersion
Obtained by dissolving 22.5 g of palladium nitrate (II) hydrate (9 g in terms of palladium metal) and 18.8 g of gold chloride (III) acid tetrahydrate (9 g in terms of gold metal) in 100 g of pure water. 50 g of an aqueous citric acid solution (manufactured by Kanto Chemical Co., Inc.) having a concentration of 5.0% by weight as a complexing stabilizer was mixed with the aqueous metal salt solution. In addition to 1800 g of monoethylene glycol as a solvent, the mixture was stirred and mixed at 100 ° C. for 6 hours in a nitrogen atmosphere to obtain a palladium-gold colloid solution in which palladium-gold composite fine particles were dispersed. Next, the palladium-gold colloid solution was concentrated with a rotary evaporator to obtain a palladium-gold colloid solution (7) having a concentration of 3.0% by weight in terms of palladium-gold metal. When the particle diameter of the obtained platinum-rhodium colloid was measured with a scanning electron microscope (manufactured by Hitachi, Ltd., S-5500), the average particle diameter was 2 nm.

[Metal Particle Preparation Example 8]
Synthesis of Pd-Pt particle dispersion
Metal salt obtained by dissolving 23.3 g of palladium nitrate (II) hydrate (9 g in terms of palladium metal) and 25 g of platinum chloride (IV) acid hexahydrate (9 g in terms of platinum metal) in 100 g of pure water. To the aqueous solution, 100 g of a citric acid (manufactured by Kanto Chemical) aqueous solution having a concentration of 5.0% by weight was added as a complexing stabilizer. A metal salt aqueous solution was added to 1800 g of monoethylene glycol as a solvent, and the mixture was stirred and mixed at 100 ° C. for 6 hours in a nitrogen atmosphere to obtain a palladium-platinum colloid solution in which palladium-platinum composite fine particles were dispersed. Next, the palladium-platinum colloid solution was concentrated with a rotary evaporator to obtain a palladium-platinum colloid solution (8) having a concentration of 3.0% by weight in terms of palladium-platinum metal. When the particle diameter of the obtained palladium-platinum colloid was measured with a scanning electron microscope (manufactured by Hitachi, Ltd., S-5500), the average particle diameter was 2 nm.

[Metal Particle Preparation Example 9]
Synthesis of Pt-Ru particle dispersion
Metal obtained by dissolving 25 g of platinum (IV) chloride hexahydrate (9 g in terms of platinum metal) and 23.3 g of ruthenium (III) chloride trihydrate (9 g in terms of ruthenium metal) in 100 g of pure water. To the salt aqueous solution, 50 g of citric acid (manufactured by Kanto Chemical) aqueous solution having a concentration of 5.0% by weight was added as a complexing stabilizer. A metal salt solution was added to 1800 g of monoethylene glycol as a solvent, and the mixture was stirred and mixed at 100 ° C. for 6 hours in a nitrogen atmosphere to obtain a platinum-ruthenium colloidal solution in which platinum-ruthenium mixed fine particles were dispersed. Subsequently, the platinum-ruthenium colloid solution was concentrated by a rotary evaporator to obtain a platinum-ruthenium colloid solution (9) having a concentration of 3.0% by weight in terms of platinum-ruthenium metal. When the particle diameter of the obtained platinum-ruthenium colloid was measured with a scanning electron microscope (manufactured by Hitachi, Ltd., S-5500), the average particle diameter was 2 nm.

[Metal Particle Adjustment Example 10]
Synthesis of Pd-Cu particle dispersion
A solution was prepared by dissolving 122 g of ferrous sulfate as a reducing agent in 219 g of an aqueous citric acid solution (concentration: 30% by mass). Then, 341 g of this solution was added to 39 g of an aqueous palladium nitrate solution (concentration 20% by mass) at room temperature, and then 10 g of an aqueous copper nitrate solution (concentration 20%) was sufficiently mixed to prepare a dispersion of Pd particles. Washed and desalted using an ultrafilter (manufactured by ADVANTEC, Ultrafilter Q0500), concentrated and concentrated to a Pd—Cu colloidal solution of 10% Pd—Cu concentration (Pd / (Pd + Cu) × 100 = 80%) (10 ) The particle diameter of the obtained Pd—Cu colloidal solution was measured with a scanning electron microscope (manufactured by Hitachi, Ltd., S-5500), and the average particle diameter was 3 nm.

[Metal Particle Preparation Example 11]
Synthesis of 40 nm Pd particle dispersion
A solution was prepared by dissolving 122 g of ferrous sulfate as a reducing agent in 219 g of an aqueous citric acid solution (concentration: 30% by mass). Then, 341 g of this solution was added to 39 g of an aqueous palladium nitrate solution (concentration 20% by mass) at room temperature, and thoroughly mixed to prepare a dispersion of Pd particles. Washing and desalting was performed using an ultrafilter (manufactured by ADVANTEC, Ultrafilter Q0500), followed by concentration to obtain a Pd colloid solution (11) having a Pd equivalent concentration of 3%. Thereafter, the particles were hydrothermally treated at 200 ° C. for 1 hour, and dispersed using a Sugino Machine Ultimizer system to obtain a 3% Pd colloid. When the particle diameter of the obtained Pd colloid was measured with a scanning electron microscope (manufactured by Hitachi, Ltd., S-5500), the average particle diameter was 40 nm.

[Example 1]
60 g of a copper nitrate (II) aqueous solution having a Cu ion concentration of 5% by mass as a metal ion source was added to 500 g of the first suspension (A) of silica prepared in Support Material Preparation Example A, and the mixture was heated at 20 ° C. for 40 minutes. Stir to prepare a mixed suspension (suspension A). The pH at this time was 2.5. Next, 900 kg of 3% Pd colloidal solution (1) was added and mixed and stirred for 10 minutes. The pH of the mixed suspension (precursor dispersion) after the addition of Pd particles was 6.5. Thereafter, desalting was performed using an amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) to obtain a metal particle-supported catalyst dispersion.
This metal particle-supported catalyst dispersion was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain a Pd particle-supported silica catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

[Example 2]
100 g of a nickel nitrate (II) aqueous solution having a Ni ion concentration of 5% by mass as a metal ion source was added to 2000 g of the first suspension (B) of ATO prepared in Carrier Material Preparation Example B, and the mixture was heated at 20 ° C. for 40 minutes. Stir (suspension A). 40 kg of 3% Pt colloidal solution (2) was added and mixed and stirred for 10 minutes. The pH of the mixed suspension (precursor dispersion) after the addition of Pt particles was 7.2. Thereafter, desalting was performed using an amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) to obtain a metal particle-supported catalyst dispersion.
This metal particle-supported catalyst dispersion was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain a Pt particle-supported ATO catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

[Example 3]
80 g of an iron (II) sulfate aqueous solution having a Fe ion concentration of 5% by mass as a metal ion source was added to 2000 g of the first ITO suspension (B) prepared in Synthesis Example C and stirred at 20 ° C. for 40 minutes. (Suspension A). Thereafter, 83.3 kg of a 3% Ru colloid solution (3) was added and mixed and stirred for 10 minutes. The pH of the mixed suspension (precursor dispersion) after the addition of Ru particles was 7.5. Thereafter, desalting was performed using an amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) to obtain a metal particle-supported catalyst dispersion.
The metal particle-supported catalyst dispersion was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain a Ru particle-supported ITO catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

[Example 4]
140 g of a palladium (II) nitrate aqueous solution having a Pd ion concentration of 5% by mass as a metal ion source was added to 1000 g of the first suspension (D) of PTO prepared in Carrier Material Preparation Example D, and the mixture was heated at 20 ° C. for 40 minutes. Stir (suspension A). 100 kg of 3% Rh colloid solution (4) was added and mixed and stirred for 10 minutes. The pH of the mixed suspension (precursor dispersion) after the addition of Rh particles was 7.5. Thereafter, desalting was performed using an amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) to obtain a metal particle-supported dispersion.
The mixed suspension was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain an Rh particle-supporting active PTO catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

[Example 5]
100 g of an aqueous solution of chloroauric acid (III) having an Au ion concentration of 5% by mass as a metal ion source was added to 2000 g of the first suspension (E) of Sb ₂ O ₅ prepared in Carrier Material Preparation Example E, and 20 Stir at 40 ° C. for 40 minutes to prepare a mixed suspension (suspension A). Thereafter, 26.7 kg of 3% Ag colloidal solution (5) was added and mixed and stirred for 10 minutes. The pH of the mixed suspension (precursor dispersion) after addition of Ag particles was 6.5. Thereafter, desalting was performed using an amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) to obtain a metal particle-supported dispersion.
The metal fluid-supported dispersion was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain an Ag particle-supported Sb ₂ O ₅ catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

[ Reference Example 6]
40 g of an aqueous silver (I) nitrate solution having an Ag ion concentration of 5% by mass as a metal ion source was added to 2000 g of the first suspension (F) of SnO ₂ prepared in Carrier Material Preparation Example F, and the mixture was stirred at 20 ° C. for 40 minutes. Stir to prepare a mixed suspension (suspension A). Thereafter, 3.3 kg of a 3% Pt—Rh colloidal solution (6) was added and mixed and stirred for 10 minutes. The pH of the mixed suspension (precursor dispersion) after the addition of Pt—Rh particles was 6.8. Thereafter, desalting was performed using an amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) to obtain a metal particle-supported catalyst dispersion.
This metal particle-supported catalyst dispersion was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain a Pt—Rh particle-supported active SnO ₂ catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

[Example 7]
60 g of a chloroplatinic acid (IV) aqueous solution having a Pt ion concentration of 5% by mass as a metal ion source was added to 10000 g of the first suspension (G) of Al ₂ O ₃ prepared in Carrier Material Preparation Example G, and 20 Stir at 40 ° C. for 40 minutes to prepare a mixed suspension (suspension A). Next, 10.0 kg of a 3% Pd—Au colloidal solution (7) was added and mixed and stirred for 10 minutes. The pH of the mixed suspension (precursor dispersion) after the addition of Pd—Au particles was 6.8. Thereafter, desalting was performed using an amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) to obtain a metal particle-supported catalyst dispersion.
The metal particle-supported catalyst dispersion was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain a Pd—Au particle-supported active alumina catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

[Example 8]
120 g of an aqueous solution of chloroauric acid (III) having an Au ion concentration of 5% by mass as a metal ion source was added to 1000 g of the first suspension (H) of γ-alumina prepared in Support Material Preparation Example H, At 40 minutes to prepare a mixed suspension (suspension A). Next, 6.7 kg of a 3% Pd—Pt colloidal solution (8) was added and mixed and stirred for 10 minutes. The pH of the mixed suspension (precursor dispersion) after the addition of Pd—Pt particles was 6.3. Thereafter, desalting was performed using an amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) to obtain a metal particle-supported dispersion.
The metal particle-supported dispersion was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain a Pd—Pt particle-supported active alumina catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

[Example 9]
200 g of an aqueous cobalt (II) chloride solution having a Co ion concentration of 5% by mass as a metal ion source was added to 2000 g of the first carbon black suspension (I) prepared in Support Material Preparation Example I, Stir for minutes to prepare a mixed suspension (Suspension A). Next, 26.7 kg of 3% Pt-Ru colloidal solution (9) was added and mixed and stirred for 10 minutes. The pH of the mixed suspension (precursor dispersion) after the addition of Pt-Ru particles was 6.2. Thereafter, desalting was performed using an amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) to obtain a metal particle-supported dispersion.
The metal particle-supported catalyst dispersion was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain a Pt—Ru particle-supported carbon black catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

[Example 10]
4 g of an aqueous copper (II) nitrate solution having a Cu ion concentration of 5 mass% was added as a metal ion source to 500 g of the first suspension (A) of silica prepared in Support Material Preparation Example A, and the mixture was added at 20 ° C. for 40 minutes. Stir to prepare a mixed suspension (suspension A). Next, 900 kg of a 3% Pd—Cu colloidal solution (10) was added and mixed and stirred for 10 minutes. The pH of the mixed suspension (precursor dispersion) after the addition of Pd—Cu particles was 6.3. Thereafter, desalting was performed using an amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) to obtain a metal particle-supported catalyst dispersion.
This metal particle-supported catalyst dispersion was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain a Pd—Cu particle-supported silica catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

[Comparative Example 1]
60 g of a copper nitrate (II) aqueous solution having a Cu ion concentration of 5% by mass as a metal ion source was added to 500 g of the first suspension (A) of silica prepared in Support Material Preparation Example A, and the mixture was heated at 20 ° C. for 40 minutes. Stir to prepare a mixed suspension (suspension A). The pH at this time was 2.5. Next, 900 kg of 3% Pd colloidal solution (11) was added and mixed and stirred for 10 minutes. The pH of the mixed suspension (precursor dispersion) after the addition of Pd particles was 6.5. Thereafter, desalting was performed using an amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) to obtain a metal particle-supported catalyst dispersion.
This metal particle-supported catalyst dispersion was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain a Pd particle-supported silica catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

[Comparative Example 2]
900 kg of a 3% Pd colloid solution (1) was added to 500 g of the first suspension (A) of silica prepared in Carrier Material Preparation Example A, and mixed and stirred for 10 minutes (Suspension A). The pH of the mixed suspension after addition of Pd particles was 6.5. Thereafter, desalting was performed using an amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) to obtain a metal particle-supported catalyst dispersion.
The metal particle-supported catalyst dispersion was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain a Pd particle-supported silica catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

[Comparative Example 3]
10000 g of a copper nitrate (II) aqueous solution having a Cu ion concentration of 5% by mass as a metal ion source was added to 500 g of the first suspension (A) of silica prepared in Support Material Preparation Example A, and the mixture was added at 20 ° C. for 40 minutes. Stir to prepare a mixed suspension (suspension A). The pH at this time was 2.5. Next, 900 kg of 3% Pd colloidal solution (1) was added and mixed and stirred for 10 minutes. The pH of the mixed suspension (precursor dispersion) after the addition of Pd particles was 6.5. Thereafter, desalting was performed using an amphoteric ion exchange resin (trade name SMNUPB, manufactured by Mitsubishi Chemical Corporation) to obtain a metal particle-supported catalyst dispersion.
The metal particle-supported catalyst dispersion was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain a Pd particle-supported silica catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

[Comparative Example 4]
This was performed using Pd by a method according to Example 1 of JP-A-11-12608.
Manufacture of [TiO ₂ -Pd] (nucleus) -Pt (surface layer) composite fine particles TiO ₂ colloid solution (catalyst chemical industry Co., Ltd .: PW-1010, solid content concentration 20 wt%) 0.8 g and polyvinylpyrrolidone 0 0.03 g was mixed, and then mixed with 150 ml of a mixed solvent of water, ethylene glycol and ethanol (weight ratio = 1: 1: 1) to prepare a dispersion liquid in which 0.2 mmol of TiO ₂ fine particles were dispersed. In 10 g of pure water, 2 mg of trisodium citrate [0.01 parts by weight in terms of Pd metal] is dissolved in advance, and 5 ml of an aqueous solution containing 2 mmol of palladium nitrate is added. 5 ml of a ferrous iron solution was added. A palladium nitrate solution with the above dispersion is mixed, stirred for 1 hour in a nitrogen atmosphere to produce TiO ₂ fine particles coated with Pd, washed with a membrane filter, and then coated with Pd with a solid concentration of 20% by weight. A TiO ₂ fine particle dispersion was prepared. After mixing 1.86 g of the above dispersion and 0.07 g of polyvinylpyrrolidone, the mixture was mixed with 150 ml of a mixed solvent of water, ethylene glycol and ethanol (1: 1: 1), and hydrogen gas was blown in for 2 hours while stirring. Hydrogen was adsorbed on the coated TiO ₂ fine particles. An aqueous solution of 4 mmol of potassium chloroplatinate was added dropwise to a Pd-coated TiO ₂ fine particle dispersion adsorbed with hydrogen over 6 hours while stirring in a nitrogen atmosphere, and then stirred for 8 hours to obtain Pd-coated TiO ₂ fine particles. Composite fine particles having a Pd surface layer formed thereon were produced. This mixed suspension was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain a Pd particle-supported silica catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

[Comparative Example 5]
According to the example of JP 2008-311141 A, an equivalent method was performed except that the metal species was changed to Pd. 10 g of silica particles (manufactured by JGC Catalysts & Chemicals Co., Ltd .: true sphere, average particle diameter 300 nm, CV value 1.0%) were dispersed in 90 g of a water / ethanol (50/50) mixed solvent. 2 g of γ-aminopropyltriethoxysilane was added to this dispersion, and the mixture was stirred for 1 hour, and then stirred at 80 ° C. for 2 hours in an autoclave and surface-treated with an amino group-containing silane compound (A -1) A dispersion was prepared. 2 kg of 3% Pd colloid solution (1) was mixed and stirred for 1 hour to prepare a composite particle dispersion. This mixed suspension was dried in a nitrogen atmosphere at a temperature of 105 ° C. for 24 hours to obtain a Pd particle-supported silica catalyst. Production conditions and evaluation of the catalyst are shown in Tables 1 and 2.

(Table 1)

(Table 2)

According to the results of [Examples 1 to 5, 7 to 10] shown in (Tables 1 and 2), after supporting metal ions on the carrier material (step [1]), metal fine particles are supported ( Step [2]), followed by desalting (Step [3]), there is no highly dispersed and unsupported metal particles, and there is no uncoated carrier part, regardless of the type of carrier material. A metal fine particle supported catalyst has been obtained.

  On the other hand, in [Comparative Example 1] using large metal particles, there are unsupported metal particles, there are uncoated carrier parts, and complete coating is difficult when particles having a large particle diameter are used. It turns out that it is.

  In addition, there are metal particles that are not supported in [Comparative Example 2] in which the metal ion is not supported and the step [1] is not provided. This is presumably because there are no metal ions at the ion exchange site on the surface of the carrier, so that the interaction due to electrostatic attraction is small, and as a result there are many unsupported metal particles.

  Even in [Comparative Example 3] in which a large amount of metal ions are used in step [1], there are metal particles that are not supported and portions that are not supported on the surface of the carrier. This is presumed to be due to the presence of excess metal ions that are not adsorbed on the surface of the carrier, and as a result, the metal particles aggregate and are not adsorbed on the surface of the carrier.

  Next, the difference in catalyst activity will be considered. About the hydrogenation reaction of acetylene, it carried out about [Example 1, 7-8, 10] and [Comparative Examples 1-5] which carry | supported the composite metal of Pd or Pd as a metal particle. The decomposition of nitrate ions was carried out for [Examples 1, 8, 10] and [Comparative Examples 1 to 3] carrying Pd and Pd—Cu as metal particles.

  Looking at the hydrogenation reaction of acetylene, the production rate of ethylene and ethane in each example is in the range of 75 to 90%, while in each comparative example is in the range of 20 to 60%. Showed activity. In particular, since each example shows higher hydrogenation activity than [Comparative Examples 4 and 5] in which the supported state of the metal particles is good, the catalytic activity of these examples is only the supported and dispersed state of the metal particles. In other words, it is considered that the activity is improved by a synergistic effect due to the metal ions and the metal particles being supported on the support material.

  The composition analysis of the metal particles and metal ions supported on each catalyst is performed by subjecting the solution of the metal particle-supported catalyst to plasma emission spectroscopic analysis, and thus does not specify the state of metal ion support on the catalyst. . However, 1) all use a carrier material that acts as an ion exchanger, 2) desalting excess metal ions not supported on the carrier material in step [3], 3 ) Since the drying process is performed under a relatively low temperature of 105 ° C. under an inert atmosphere (nitrogen atmosphere) and the possibility of advancing the oxidation and reduction of metal ions is low, There is a high possibility that the metal ions are supported in an ion exchanged state on the ion exchange site of the support material.

However, the presence of oxides, carrier metals, and metal salts derived from the metal ions ion-exchanged at the ion exchange site does not hinder the activity of the metal particle-supported catalyst. Moreover, even if it is confirmed that the metal ions are not actually supported in the ion exchange site of the carrier material in the state of being ion exchanged, the metal ions are manufactured through the steps [1] to [3]. It is clear that the activity of the metal particle-supported catalyst according to the example is higher than that of the comparative example. Further, this tendency does not depend on the selection of the active metal (metal particles), and is considered to be the same in [Examples 2 to 5 , 9] in which the activity test is not performed.

  Further, in the decomposition test of nitrate ions, the decomposition rate of nitrate ions in each example is in the range of 90 to 98%, while in each comparative example, it is in the range of 25 to 55%, and the examples show higher decomposition activity. ing. Therefore, the dispersion of the metal particles is good, and the synergistic effect due to the support of the metal particles and the metal ions on the support material is exerted to improve the activity of not only the hydrogenation of acetylene but also other reactions. It was confirmed that it was also demonstrated in

  In terms of electrical characteristics, the specific resistance value in each example is in the range of 0.01 to 1.2 [Ω · cm], while in each comparative example, the range is 25.8 to 3500 [Ω · cm]. The example shows higher conductivity. Therefore, the dispersion state of the metal particles is good, and there is little influence of polymer etc. From this point, improvement of electrical characteristics, improvement of catalytic activity, improvement of gas adsorption amount is suggested and it can be demonstrated in other reactions. Was confirmed.

Claims (9)

The manufacturing method of the metal particle supported catalyst characterized by including the process of following [1]-[4].
[1] The following (Ia) to (Ic) are selected from the following (Ia) to (Ic) for a first suspension in which a carrier material containing an ion exchanger (where the average particle size of primary particles is 1 to 500 nm) is dispersed in a solvent. One or more kinds of metal ions are added at a ratio of 0.1 to 100 parts by mass in terms of metal elements with respect to 100 parts by mass of the carrier substance, and the metal ions are supported on the carrier substance to prepare a suspension A. Process.
(Ia) Metal ion selected from the fourth period transition metal element (Ib) Metal ion selected from the fifth period transition metal element (Ic) Platinum ion or gold ion [2] Following the step [1], the suspension While adjusting the temperature of the suspension A to 15 to 40 ° C., 200 to 100000 parts by mass of metal particles having an average particle diameter of 1 to 20 nm selected from the following (IIa) to (IId) are added to 100 parts by mass of the carrier substance. And mixing to prepare a precursor dispersion of the metal particle-supported catalyst.
(IIa) Metal particles selected from fourth period transition metal elements (IIb) Metal particles selected from fifth period transition metal elements (IIc) Platinum particles or gold particles (IId) At least selected from (IIa) to (IIc) Metal particles formed by combining two or more metals [3] Subsequent to the step [2], in order to remove metal ions not supported on the support material, a precursor dispersion of the metal particle-supported catalyst is used. A step of obtaining a metal particle-supported catalyst dispersion by desalting.
[4] The metal particle-supported catalyst dispersion obtained in the step [3] is dried at a temperature of 100 to 200 ° C. to obtain a metal particle-supported catalyst having a coating layer of metal particles having a thickness of 1 to 50 nm. Process.   The amount of metal ions with respect to the carrier material after the desalting treatment in the step [3] is 0.001 to 10 parts by mass with respect to 100 parts by mass of the carrier material. A process for producing a metal particle-supported catalyst according to claim 1. In the step [1], the relationship between the mass of the metal ions supported on the carrier substance and the mass of the metal particles added to the suspension A in the step [2] is expressed by the following formula (1). The method for producing a metal particle-supported catalyst according to claim 1, wherein the value of the formula expressed by the formula is in the range of 0.0001 to 0.005.
Mass of metal ion / (mass of metal ion + mass of metal particle) (1)   The method for producing a metal particle-supported catalyst according to any one of claims 1 to 3, wherein the drying treatment in the step [4] is performed in an inert atmosphere. The fourth period transition metal element is an element selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, and Cu, and the fifth period transition metal element is Zr, Nb, Mo, Tc. , Ru, Rh, method of producing metal particles supported catalyst according to any one of claims 1 to 4, characterized in that an element selected from the group consisting of P d and Ag. The method for producing a metal particle-supported catalyst according to any one of claims 1 to 5, wherein a ratio of the metal particles contained in the metal particle-supported catalyst is 40 to 99.9 mass%. The carrier material is selected from an inorganic carrier material or an organic carrier material, and the inorganic carrier material or the organic carrier material is selected from the group consisting of Si, Al, C, Ti, Zr and Ce. The method for producing a metal particle-supported catalyst according to any one of claims 1 to 6 , wherein the method contains at least one element. The carrier material is composed of tin oxide, antimony-doped tin oxide (ATO), tin oxide-doped indium oxide (ITO), antimony pentoxide, silicotungstic acid, phosphorus-doped tin oxide (PTO), and aluminum-doped zinc oxide (AZO). The method for producing a metal particle-supported catalyst according to any one of claims 1 to 7 , wherein the method comprises one or more compounds. Ri Na is manufactured by the method according to any one of claims 1 to 8, comprising an element wherein the metal particles are Ru, Rh, Pd, Ag, selected from the group consisting of Pt and Au, unsaturated hydrocarbons A metal particle-supported catalyst used for hydrogenation reaction of hydrogen or for hydrocracking reaction of nitric acids .