JP5806101B2 - Porous silica oligomer-coated particles, supported catalyst, and production method thereof - Google Patents

Description

  The present invention relates to porous silica oligomer-coated particles, supported catalysts, and methods for producing them.

Conventionally, various catalysts have been proposed as catalysts used for purifying exhaust gas in which metal particles are supported on a carrier. For example, a material obtained by supporting various metal particles called active metals (for example, Pt (platinum), Pd (palladium), Cu (copper), etc.) on a support material (for example, alumina, zeolite, etc.) has been proposed.
Various methods for producing metal particle-supported catalysts by supporting metal particles on a carrier have been proposed. For example, a carrier material is introduced into a solution in which a metal to be supported is dissolved, and metal particles are precipitated on the carrier material, or a carrier material is introduced into a metal particle dispersion in which colloidal minute particles are dispersed. And a method of supporting metal particles.

  For example, in Patent Document 1, in a method of depositing fine metal particles having catalytic activity on the surface of fine carrier particles made of metal oxide or the like, it matches the absorption band of at least one raw material for synthesizing the carrier. An absorption band of the raw material is simultaneously applied to the step of irradiating the raw material with light including a wavelength to precipitate the carrier particles, and the raw material for depositing the precipitated carrier particles and the metal particles having catalytic activity. A method for producing a catalyst, comprising: a step of irradiating light having a wavelength matching the above and depositing the metal particles on the surface of the carrier particles; and a step of selectively collecting the deposited metal particles. Have been described.

  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. In addition, 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. A colloidal particle dispersion comprising: a colloidal particle dispersed therein to form a colloidal particle; and the polymer is adsorbed on the particle to protect the particle substantially individually and separately as a protective colloidal particle; The colloidal particle dispersion is brought into contact with the solid support, and at least one of the polymer compound and the solid support does not have a functional group that can act to form a covalent bond and form a chemical bond therebetween, thus Metal particles characterized by forming a particle-supported complex formed by adsorbing the particles protected by the polymer compound to the solid support, and isolating the obtained complex from the dispersion medium, and /or Method for producing a metal compound particles carrying complexes have been described.

  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 described.

  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 described.

  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 by a deposition support method is described. In addition, as a production method thereof, a production method is described in which a carrier containing at least one of gold and its compound and at least one of a second element and its compound is heat-treated.

  When such conventional metal particle-supported catalysts continue to be used, the metal particles cause fusion, aggregation, and particle growth, and as a result, there are problems in that the catalytic activity is reduced and the life is shortened. Such a problem becomes particularly noticeable when used at high temperatures.

On the other hand, a catalyst for a polymer electrolyte fuel cell (PEFC) electrode has been proposed. Patent Document 6 describes surface-modified metal nanoparticles characterized by having a porous material made of an inorganic oxide on the surface of nanoparticles containing platinum group metals. Nanoparticles are remarkably suppressed from aggregating with each other, and their activity is sustained, and it is possible to produce a catalyst using them to provide a polymer electrolyte fuel cell having excellent properties. Has been.
Patent Document 6 describes that there is no particular limitation on the pore size as long as the fuel can be diffused to the surface of the metal nanoparticles, but the specific size is not described at all. Absent.
In Patent Document 6, there is no particular limitation on the porous film thickness as long as the metal nanoparticles can be prevented from coming into contact with each other. However, it is caused by diffusion of the fuel to the metal nanoparticle surface or an oxidation reaction. It is described that it is preferable to have a thickness that does not inhibit the conduction of electrons to the carrier, specifically, an ultrathin silica layer of approximately 0.5 to 2 nm is described, As an example, it is only described that the porous film thickness was about 1 nm.

Japanese Patent Laid-Open No. 61-268359 JP-A-5-293383 JP-A-6-31181 JP 2003-13105 A JP 2003-053188 A JP 2005-276688 A

  Judging from the fact that the surface-modified nanoparticles described in Patent Document 6 are described as described above, it is assumed that these surface-modified nanoparticles are also used as a catalyst for polymer electrolyte fuel cell electrodes. The thickness of the porous layer needs to be so thin that the fuel diffuses to the surface of the metal nanoparticles and the electrons conduct, and conversely, the porous layer is so thin. The pores of the porous layer are not considered essential.

  In addition, as described above, since there is no specific description of the size of the porous pore diameter in Patent Document 6, the present inventor has disclosed the metal fine particles as described in Example 1 of Patent Document 6. Surface-modified metal nanoparticles in which the surface of metal fine particles was covered with silica were produced by a method of treating the surface with aminosilane and then with water glass, and the silica layer was observed. As a result, it was confirmed that the pore diameter was remarkably small (generally 1 nm or less) even with respect to the pore which may be slightly present, with few pores. Moreover, when the catalytic activity of the obtained surface-modified metal nanoparticles was measured, it was confirmed that it was extremely low.

Thus, the porous layer in the surface-modified metal nanoparticles described in Patent Document 6 had almost no pores and low catalytic activity. On the other hand, even though the catalysts as described in Patent Documents 1 to 5 have high activity, they have a short life because aggregation occurs due to use.
Thus, conventionally, there has been no catalyst that has a high activity and has a long life and can maintain its activity for a long period of time.

An object of the present invention is to solve the above problems.
That is, an object of the present invention is to provide a supported catalyst that has high activity and maintains its activity for a long period of time, porous silica oligomer-coated particles that can constitute a part thereof, and a method for producing them.

The inventor has intensively studied to solve the above-mentioned problems, and has completed the present invention.
The present invention includes the following (1) to (11).
(1) having metal core particles and a porous silica oligomer layer attached to at least a part of the surface thereof,
The porous silica oligomer layer comprises a silica-based compound having at least one siloxane bond;
Porous silica oligomer-coated particles, wherein the porous silica oligomer layer has an average pore diameter of more than 0.2 nm and less than 8 nm.
(2) A silica-based precursor obtained by hydrolysis and polycondensation of a hydrolyzable organosilicon compound represented by the following formula (I) is brought into contact with the metal core particles in a solvent, and then a solid content is obtained. The porous silica oligomer-coated particles according to the above (1), wherein the porous silica oligomer particles are separated from the solvent.
R ¹ _a Si (OR ² ) _4-a Formula (I)
Here, R ¹ represents a hydrogen atom, a halogen atom, an alkyl group, a halogenated alkyl group, a vinyl group, an aryl group or an acrylic group, and R ² represents a hydrogen atom, an alkyl group, a halogenated alkyl group, a vinyl group or an aryl group. Represents an acrylic group or —C ₂ H ₄ OC _n H _{2n + 1} (n = 1 to 4), and a is an integer of 1 to 3.
(3) The porous silica oligomer-coated particles according to the above (1) or (2), wherein the average value of the thickness of the porous silica oligomer layer is more than 2 nm.
(4) The porous silica oligomer-coated particles according to any one of (1) to (3) above, wherein the pore volume is 0.01 to 0.5 ml / g.
(5) The porous silica oligomer-coated particles according to any one of (1) to (4), wherein the specific surface area is 100 to 1000 m ² / g.
(6) The porous silica oligomer-coated particles according to any one of (1) to (5), wherein the silica compound has a molecular weight (in terms of polystyrene) of 500 to 30,000 g / mol.
(7) Said (1)-(6) whose said metal core particle has as a main component at least 1 chosen from the group which consists of a 4th period transition element, a 5th period transition element, platinum, gold | metal | money, osmium, and iridium. The porous silica oligomer-coated particles according to any one of 1).
(8) A supported catalyst in which the porous silica oligomer-coated particles according to any one of (1) to (7) are supported on the surface of a support.
(9) a colloid adjusting step for obtaining a colloid solution in which the metal core particles are dispersed;
An oligomer forming step of hydrolyzing and polycondensing the hydrolyzable organosilicon compound represented by the formula (I) to obtain a solution containing a silica-based precursor;
A coating step of mixing the colloid solution and a solution containing the silica-based precursor to obtain a dispersion (X) containing precursor-coated particles;
A method for producing porous silica oligomer-coated particles, comprising: a pore forming step of obtaining porous silica oligomer-coated particles by separating the solvent and solid content contained in the dispersion (X).
(10) The method for producing porous silica oligomer-coated particles according to (9), wherein the porous silica oligomer-coated particles according to any one of (1) to (7) are obtained.
(11) a colloid adjusting step for obtaining a colloid solution in which the metal core particles are dispersed;
An oligomer forming step of hydrolyzing and polycondensing the hydrolyzable organosilicon compound represented by the formula (I) to obtain a solution containing a silica-based precursor;
A coating step of mixing the colloid solution and a solution containing the silica-based precursor to obtain a dispersion (X) containing precursor-coated particles;
An addition step of adding a carrier to the dispersion (X) to obtain a dispersion (Y);
A method for producing a supported catalyst, comprising: separating a solvent and solid content contained in the dispersion (Y) to obtain a supported catalyst in which porous silica oligomer-coated particles are supported on a support.

  According to the present invention, it is possible to provide a supported catalyst that has high activity and that maintains its activity for a long period of time, porous silica oligomer-coated particles that can constitute a part thereof, and a method for producing them.

The present invention will be described.
The present invention has a metal core particle and a porous silica oligomer layer on at least a part of the surface thereof, and the porous silica oligomer layer contains a silica-based compound having at least one siloxane bond, and is porous. The porous silica oligomer-coated particles have an average pore diameter of the pores of the silica oligomer layer of more than 0.2 nm and less than 8 nm.
Hereinafter, such porous silica oligomer-coated particles are also referred to as “coated particles of the present invention”.

The present invention is also a supported catalyst in which the coated particles of the present invention are supported on the surface of a carrier.
Hereinafter, such a supported catalyst is also referred to as “the supported catalyst of the present invention”.
The supported catalyst of the present invention includes, for example, an HC (hydrocarbon) decomposition system (for example, a three-way catalyst for exhaust gas purification of automobiles, decomposition of volatile organic compounds (VOC)), a high-concentration nitric acid decomposition system (for example, nitric acid) Nitrogen is reduced to generate nitrogen), which is suitable as a catalyst used in a hydrogenation reaction system.

<Metal core particles>
First, the metal core particles in the coated particles of the present invention will be described.
The metal core particle in the coated particle of the present invention is not particularly limited as long as it is a metal having catalytic ability. The fourth period transition element, the fifth period transition element, platinum (Pt), gold (Au), osmium (Os) and Preferably, the main component is at least one selected from the group consisting of iridium (Ir), and at least one selected from the group consisting of Pt, Pd, Rh, Ru, Os, Ir, Cu, Au, and Ag. More preferably, the main component is one.
Here, the fourth period transition element means Sc, Ti, V, Cr, Mn, Fe, Co, Ni, and Cu. The fifth period transition element means Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd and Ag.

The “main component” here means that the content is 70% by mass or more. That is, the fourth periodic transition element (Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu), the fifth periodic transition element (Y, Zr, Nb, Mo, Tc, Ru, Rh) in the metal core particle. , Pd, Ag), platinum (Pt), gold (Au), osmium (Os), and iridium (Ir), the total content is preferably 70% by mass or more. The content is more preferably 80% by mass or more, more preferably 90% by mass or more, more preferably 95% by mass or more, more preferably 99% by mass or more, and 100% by mass. In other words, the metal core particle is substantially selected from the group consisting of the fourth period transition element, the fifth period transition element, platinum (Pt), gold (Au), osmium (Os), and iridium (Ir). More preferably, it consists of at least one. Here, “becomes substantially” means that impurities inevitably contained from the raw materials and the production process can be contained, but other than that are not contained.
Unless otherwise specified, in the description of the present invention, “main component” and “substantially become” are used in this sense.

  When the metal core particle includes two or more elements selected from the group consisting of a fourth periodic transition element, a fifth periodic transition element, platinum (Pt), gold (Au), osmium (Os), and iridium (Ir). It is preferable because the metal core particles tend to be chemically stabilized. The metal core particles include Pd—Pt (meaning that Pd and Pt are contained. The same applies hereinafter), Pd—Ag, Pd—Au, Pd—Cu, Pt—Ag, Pt—Au, Pt—Cu, Pt— A composition of Ru, Au—Ag, or Au—Ru is preferable. Further, Sn is preferably contained, and the composition is Ag—Pd—Sn or Pd—Cu—Sn.

  As a component that the metal core particle may contain in addition to the fourth periodic transition element, the fifth periodic transition element, platinum (Pt), gold (Au), osmium (Os), and iridium (Ir), Sn, La, Ce, Pr.

A method for measuring the component (composition) contained in the metal core particles in the present invention will be described.
The component (composition) contained in the metal core particle is obtained by calcining the metal core particle, the coated particle of the present invention or the supported catalyst of the present invention at 600 ° C., melting the residue with an alkali melting agent, and then adding 28% by mass hydrochloric acid or nitric acid. After dissolving with an aqueous solution and diluting the obtained solution with pure water, measurement is performed using an ICP inductively coupled plasma emission spectrometer (for example, SPS1200A, manufactured by Seiko Denshi Co., Ltd.). When the same element is contained in the metal core particle and the porous silica oligomer layer, the coated particle of the present invention or the supported catalyst of the present invention is subjected to surface analysis (element distribution analysis) by EDX, and the metal core particle and porous Obtain the abundance ratio of the element in the silica oligomer layer, and calculate the content ratio of the components that make up the metal core particles from the obtained abundance ratio and the composition of each component using the ICP inductively coupled plasma emission spectrometer. And ask for it.

  The average particle diameter of the primary particles of the metal core particles is not particularly limited, but is preferably 0.5 to 100 nm, more preferably 1 to 50 nm, more preferably 1 to 40 nm, and more preferably 1 to 20 nm. It is more preferable that it is 1-15 nm. In such a range, it can be easily produced, and the catalytic activity of the supported catalyst of the present invention in which the coated particles of the present invention are supported on a carrier is higher than when the particle diameter is too large. Because it becomes.

  Here, the average particle diameter of the primary particles of the metal core particles means a value measured by an image analysis method. The image analysis method uses a scanning electron microscope to photograph metal core particles at a magnification of 300,000 times, arbitrarily select 100 metal core particles from the obtained photograph, and each projected area has an equivalent circle diameter. Is a method for obtaining a particle size distribution by measuring and then calculating an average particle size (median diameter) therefrom.

  The shape of the metal core particle is not particularly limited. For example, the shape may be spherical, tetrahedral (triangular pyramid), hexahedral (cubic or cuboid, hereinafter also referred to as “square”), octahedral, or indefinite. Can be mentioned.

  The metal core particles preferably form chain particles in which several (for example, 4 to 30) primary particles having an average particle diameter as described above are connected in a bead shape.

  The shape and form of the metal core particles are photographed at a magnification of 300,000 times using a scanning electron microscope, as in the case of measuring the average particle diameter of the primary particles of the metal core particles as described above. This can be confirmed.

<Porous silica oligomer layer>
Next, the porous silica oligomer layer in the coated particles of the present invention will be described.
The porous silica oligomer layer in the coated particle of the present invention is attached to at least a part of the surface of the metal core particle. The coated particles of the present invention preferably have an embodiment in which a porous silica oligomer layer is attached to the entire surface of the metal core particles, that is, the metal core particles are covered with the porous silica oligomer layer.

The porous silica oligomer layer in the present invention contains a silica-based compound having at least one siloxane bond (—Si—O—Si—).
The content of the silica-based compound in the porous silica oligomer layer is preferably 70% by mass or more, preferably 80% by mass or more, more preferably 90% by mass or more, and 95% by mass or more. More preferably, it is 99% by mass or more, and more preferably 100% by mass (the porous silica oligomer layer consists essentially of the silica-based compound) (here, “substantially The meaning of “becomes” is as described above).

  The molecular weight of the silica-based compound is not particularly limited, but the average molecular weight is preferably 500 g / mol or more, more preferably 600 g / mol or more, and further preferably 700 g / mol or more. Moreover, it is preferable that it is 30000 g / mol or less, It is more preferable that it is 20000 g / mol or less, It is further more preferable that it is 10,000 g / mol or less.

  The porous silica oligomer layer may include, for example, a collection of a plurality of the silica-based compounds having such a molecular weight, or may include the silica-based compound of one molecule.

  Further, the number of siloxane bonds contained in the silica-based compound of one molecule is not particularly limited, but is preferably 2 or more, more preferably 3 or more, and still more preferably 4 or more. Moreover, it is preferable that it is 120,000 or less, It is more preferable that it is 80000 or less, It is further more preferable that it is 40000 or less.

The silica-based compound may have a form in which siloxane bonds are linearly connected, and one molecule (for example, a hydrolysis product of a hydrolyzable organosilicon compound described later) and another molecule are connected in a network. Thus, an embodiment in which a siloxane bond is present may be used.
Further, the silica-based compound may have a mode in which, for example, a linear siloxane bond is a main chain, and a hydrogen atom or a halogen atom is bonded to this, or a side chain is bonded. Here, as a side chain, an alkyl group (preferably an alkyl group having 1 to 8 carbon atoms), a halogenated alkyl group, a vinyl group, an aryl group, an acrylic group, and —C ₂ H ₄ OC _n H _{2n + 1} (n = 1 to 4).

The silica-based compound is preferably the same as that obtained by hydrolysis and polycondensation of a hydrolyzable organosilicon compound.
Here, the hydrolyzable organosilicon compound is represented by the following formula (I).
R ¹ _a Si (OR ² ) _4-a Formula (I)
Here, R ¹ is a hydrogen atom, a halogen atom, an alkyl group (preferably an alkyl group having 1 to 8 carbon atoms), a halogenated alkyl group, a vinyl group, an aryl group (phenyl group, benzyl group, tolyl group, naphthyl group). , O-xylyl group, etc.) or an acrylic group, R ² is a hydrogen atom, an alkyl group (preferably an alkyl group having 1 to 8 carbon atoms), a halogenated alkyl group, a vinyl group, an aryl group (phenyl group, benzyl). group, a tolyl group, a naphthyl group, etc. o- xylyl group), represents an acryl group or _{-C 2 H 4 OC n H 2n} + 1 (n = 1~4), a is an integer of 1 to 3. When a is 2 or 3 (ie when R ¹ is plural), each R ¹ may be different. The same applies to R ² .

What is obtained by hydrolysis and polycondensation of such a hydrolyzable organosilicon compound based on the following formulas (II) to (IV) is preferably the silica compound.
R ¹ _a Si (OR ² ) _4-a + H ₂ O → R ¹ _a Si (OH) _b (OR ² ) _{(4-a) -b} + bR ² OH
(B is an integer of 1 to 3, where b ≦ 4-a.) Formula (II)
-SiOH + HOSi- → -Si-O- Si- + H 2 O ··· formula (III)
^{-SiOH + R 2 OSi- → -Si-} O-Si- + R 2 OH ··· formula (IV)

  Specific examples of hydrolyzable organosilicon compounds include tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, tetraoctylsilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, and methyl. Examples include triisopropoxysilane, vinyltrimethoxysilane, phenyltrimethoxysilane, and dimethyldimethoxysilane.

  The porous silica oligomer layer is obtained by contacting a silica-based precursor obtained by hydrolysis and polycondensation of the hydrolyzable organosilicon compound represented by the above formula (I) with the metal core particles in a solvent. Then, it is preferably formed on the surface of the metal core particle by separating the solid content and the solvent.

For example, the hydrolyzable organosilicon compound represented by the above formula (I) is added to a mixed solvent of, for example, a water-organic solvent (for example, alcohol) together with an acid catalyst or an alkali catalyst, and heated and heated as necessary. By stirring, the hydrolyzable organosilicon compound can be hydrolyzed and polycondensed to obtain a solution containing the silica precursor. Here, the molecular weight of the silica-based precursor is preferably 500 to 30000 g / mol, preferably 1000 to 20000 g / mol, preferably 2000 to 4500 g / mol, as measured by GPC (details will be described later). More preferably, it is mol.
And the said metal core particle can be added to this solution, and the said silica type precursor and the said metal core particle can be made to contact in a solvent. Here, the colloidal solution in which the metal core particles are dispersed is added to the solution containing the silica precursor, and the silica precursor and the metal core particles are heated and stirred as necessary. It is preferable to contact in a solvent. By doing in this way, the said silica type precursor adheres to the surface of the said metal core particle.
Then, when solid content and the said solvent are isolate | separated, the porous silica oligomer layer will be formed in the surface of the said metal core particle, and the coating particle of this invention will be obtained as solid content. Here, the method of separating the solid content and the solvent is not particularly limited, but after contacting the silica-based precursor and the metal core particles in a solvent, by exposing the solution to a dry atmosphere, It is preferable to dry the solvent to separate it from the solid content.

Examples of the component that the porous silica oligomer layer may contain other than the silica-based compound include an oxide of at least one element selected from the group consisting of elements in the third to sixth periods. Specific examples include SiO ₂ , Al ₂ O ₃ , TiO ₂ , and ZnO.
The content of components other than the silica-based compound in the porous silica oligomer layer is preferably 30% by mass or less, preferably 20% by mass or less, more preferably 10% by mass or less. More preferably, it is more preferably 1% by mass or less, and even more preferably 0% by mass (that is, the porous silica oligomer layer consists essentially of the silica-based compound) (wherein The meaning of “substantially become” is as described above).
Here, the content rate of each component in a porous silica oligomer layer shall be measured with the method similar to the measuring method of the component (composition) which the metal core particle of the above-mentioned this invention contains.

The porous silica oligomer layer has pores having an average pore diameter of more than 0.2 nm and less than 8 nm. Within such a range, the activity of the supported catalyst of the present invention in which the coated particles of the present invention are supported on a carrier is high, and the activity is maintained for a long time even when used. If the average pore diameter of the pores of the porous silica oligomer layer is too large, the life of the supported catalyst of the present invention tends to be shortened. Conversely, if the average pore diameter is too small, the activity of the supported catalyst of the present invention is reduced. Tend to be lower.
The average pore diameter is preferably 0.2 to 7 nm, more preferably 0.5 to 5.0 nm, and still more preferably 0.8 to 4.0 nm.

Here, the average pore diameter (average pore diameter) of the porous silica oligomer layer means a value obtained by measurement by the following nitrogen adsorption method [1].
The nitrogen adsorption method [1] will be described.
First, the dried measurement object (0.2 g) is placed in a measurement cell as a sample, degassed in a nitrogen gas stream at 250 ° C. for 40 minutes, and then the sample is treated with 30 vol% nitrogen and helium. A liquid nitrogen temperature is maintained in a 70% by volume mixed gas stream, and nitrogen is adsorbed on the sample to obtain a nitrogen adsorption / desorption isotherm. Then, using the obtained nitrogen adsorption / desorption isotherm, a BJH (Barret-Joyner-Halenda) method is used to obtain a pore size distribution curve of the sample, and the mesopores (pores on the particle surface) side appearing on the curve and Of the peaks on the macropore (interparticle pore) side, the pore diameter on the mesopore side is determined as the average pore diameter. Such a nitrogen adsorption method can be performed using, for example, a conventionally known pore distribution measuring apparatus (for example, BELSORP-mini (II) manufactured by Nippon Bell Co., Ltd.).
In the present invention, the average value of the pore diameter (average pore diameter) of the porous silica oligomer layer means a value measured by the nitrogen adsorption method [1] shown here unless otherwise specified.

  The porous silica oligomer layer preferably has a pore volume of 0.01 to 0.5 ml / g with respect to the unit mass of the coated particles of the present invention, preferably 0.03 to 0.3 ml / g. It is more preferable that it is 0.06-0.1 ml / g. Within such a range, the activity of the supported catalyst of the present invention in which the coated particles of the present invention are supported on a carrier is higher, and even when used, the activity is maintained for a longer period, which is preferable. If the pore volume formed in the porous silica oligomer layer is too large, the life of the supported catalyst of the present invention tends to be shortened. Conversely, if the pore volume is too small, the supported catalyst of the present invention The activity tends to be low.

Here, the pore volume of the porous silica oligomer layer means a value obtained by measurement by the following nitrogen adsorption method [2].
The nitrogen adsorption method [2] will be described.
First, the dried measurement object (0.2 g) is placed in a measurement cell as a sample, degassed in a nitrogen gas stream at 250 ° C. for 40 minutes, and then the sample is treated with 30 vol% nitrogen and helium. A liquid nitrogen temperature is maintained in a 70% by volume mixed gas stream, and nitrogen is adsorbed on the sample to obtain a nitrogen adsorption / desorption isotherm. Then, the integrated value of the mesopore side portion in the IV hysteresis curve defined by IUPAC, where the value of the relative pressure P / P _{0 in} the obtained nitrogen adsorption / desorption isotherm appears in the range of 0.4 to 1.0, And obtain this as the volume of the pores. Such a nitrogen adsorption method can be performed using, for example, a conventionally known pore distribution measuring apparatus (for example, BELSORP-mini (II) manufactured by Nippon Bell Co., Ltd.).
In the present invention, the pore volume of the porous silica oligomer layer means a value measured by the nitrogen adsorption method [2] shown here unless otherwise specified.

  The thickness of the porous silica oligomer layer is not particularly limited, but the average value is preferably more than 2 nm, more preferably 2.5 nm or more, and further preferably 3 nm or more. In addition, the average thickness of the porous silica oligomer layer is preferably 50 nm or less, more preferably 40 nm or less, more preferably 20 nm or less, and even more preferably 10 nm or less. More preferably, it is 7 nm or less. Within such a range, the activity of the supported catalyst of the present invention in which the coated particles of the present invention are supported on a carrier is higher, and even when used, the activity is maintained for a longer period, which is preferable. If the thickness of the porous silica oligomer layer is too thick, the activity of the supported catalyst of the present invention tends to be low. Conversely, if the thickness is too thin, the life of the supported catalyst of the present invention tends to be short.

  Here, the thickness of the porous silica oligomer layer was determined by taking a photograph of the coated particles of the present invention at a magnification of 300,000 times using a scanning electron microscope, and arbitrarily selecting 100 coated particles of the present invention from the obtained photographs. The thickness of the porous silica oligomer layer in each of the coated particles of the present invention was measured several times and averaged to obtain the thickness of the porous silica oligomer layer in the coated particle of the present invention. By simply averaging the data, the thickness of the porous silica oligomer layer in the sample (group of coated particles of the present invention) is obtained.

The porous silica oligomer layer has pores having the average diameter and volume as described above, and preferably has the thickness as described above, but the average of the thickness and pore diameter of the porous silica oligomer layer When the balance between the diameter and the volume is suitable, the activity of the supported catalyst of the present invention in which the coated particles of the present invention are supported on a carrier is higher, and the activity is maintained for a longer period of time even when used. The inventor found out.
Specifically, the average pore diameter of the pores of the porous silica oligomer layer is 0.5 to 5 nm, the pore volume is 0.05 to 0.15 ml / g, and the porous silica oligomer When the thickness of the layer is 2 to 8 nm, the activity of the supported catalyst of the present invention in which the coated particles of the present invention are supported on a carrier is higher, and the activity is maintained for a longer period even when used.

<Coated particles of the present invention>
The coated particles of the present invention can have specific wettability. Specifically, the contact angle in the coated particles of the present invention is about 10 to 40 degrees, preferably 15 to 35 degrees, and more preferably 15 to 30 degrees.
The contact angle was obtained by drying 1 g of the coated particles of the present invention at 200 ° C., and then putting it in a cell having a diameter of 1 cm and a height of 5 cm and pressing it with a load of 50 kgf to obtain a molded product. It shall mean the value obtained by measuring a drop of water on the surface of the object.

Is not particularly limited specific surface area of the coated particles of the present invention is preferably 100~1000m ² / g, more preferably 130~900m ² / g, more to be 150~800m ² / g Preferably, it is 200-600 m < ² > / g. Within such a range, the activity of the supported catalyst of the present invention in which the coated particles of the present invention are supported on a carrier is higher, and even when used, the activity is maintained for a longer period, which is preferable. If the specific surface area is too large, the activity of the supported catalyst of the present invention tends to be low. Conversely, if the specific surface area is too small, the life of the supported catalyst of the present invention tends to be short.
The specific surface area means a value obtained by measurement by the following nitrogen adsorption method [3] (BET method).
The nitrogen adsorption method [3] will be described.
First, a measurement object (here, coated particles of the present invention) dried (0.2 g) is placed in a measurement cell as a sample, degassed at 250 ° C. for 40 minutes in a nitrogen gas stream, The sample is kept at a liquid nitrogen temperature in a mixed gas stream of 30% by volume of nitrogen and 70% by volume of helium, and nitrogen is adsorbed on the sample by equilibrium. Next, the temperature of the sample is gradually raised to room temperature while flowing the above mixed gas, the amount of nitrogen desorbed during that time is detected, and the specific surface area of the sample is measured. The nitrogen adsorption method [3] (BET method) can be performed using, for example, a conventionally known surface area measuring device.
In the present invention, the specific surface area means a value measured by the nitrogen adsorption method [3] (BET method) shown here unless otherwise specified.

The coated particles of the present invention are those in which the porous silica oligomer layer is attached to at least a part of the surface of the metal core particles.
In the coated particles of the present invention, the mass ratio of the metal core particles and the porous silica oligomer layer is not particularly limited, but the ratio of the mass of the porous silica oligomer layer to the mass of the metal core particles (mass of porous silica oligomer layer / metal The mass of the core particles) is preferably 0.1 to 5000, more preferably 0.5 to 3000, more preferably 1 to 2000, and more preferably 1 to 1000, It is more preferably 1 to 500, and further preferably 1 to 100. Within such a range, the activity of the supported catalyst of the present invention in which the coated particles of the present invention are supported on a carrier is higher, and even when used, the activity is maintained for a longer period, which is preferable.

  Here, the mass of the metal core particles and the porous silica oligomer layer in the coated particles of the present invention is obtained by calcining the coated particles of the present invention or the supported catalyst of the present invention at 600 ° C. and melting the residue with an alkali melting agent. After dissolving with 28% by mass hydrochloric acid or nitric acid aqueous solution and diluting the obtained solution with pure water, the content rate is measured using an ICP inductively coupled plasma emission spectrometer (for example, SPS1200A, manufactured by Seiko Electronics Co., Ltd.). , And calculate from that. When the same element is contained in the metal core particle and the porous silica oligomer layer, the coated particle of the present invention or the supported catalyst of the present invention is subjected to surface analysis (element distribution analysis) by EDX, and the metal core particle and porous The content ratio of the components contained in the porous silica oligomer layer is determined from the obtained abundance ratio and the composition of each component using the ICP inductively coupled plasma optical emission spectrometer described above. Is calculated from the above.

The average particle diameter (median diameter) of the coated particles of the present invention is not particularly limited, but is preferably 1 to 500 nm, more preferably 2 to 100 nm, and even more preferably 3 to 50 nm.
Here, the average particle diameter of the coated particles of the present invention is such that a measurement object (here, coated particles of the present invention) is added to a sodium hexametaphosphate aqueous solution and dispersed by ultrasonic dispersion and stirring, and the transmittance is 70 to 90. After adjusting to be%, it means a value calculated by measuring a particle size distribution using a conventionally known laser scattering method (for example, HORIBA LA-950V2).

Next, the supported catalyst of the present invention will be described.
The supported catalyst of the present invention is one in which the coated particles of the present invention are supported on the surface of a carrier.

The carrier is not particularly limited as long as it can carry the metal core particles, and for example, an inorganic carrier containing at least one selected from the group consisting of Si, Al, C, Ti, Zr, and Ce as a main component. Is mentioned.
Other components that the support may contain include alkali metals, alkaline earths, rare earths, transition metals (eg, Li, Na, K, Rb, Cs, Mg, Ca, Sr, La, Pr, Nd, Pm, Sm, Eu , Gd, Tb, Dy, Sc, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Nb, Mo).
The carrier may be amorphous or crystalline, and may be a synthetic substance or a natural mineral.
The inorganic carrier containing at least one selected from the group consisting of Si, Al, C, Ti, Zr and Ce is preferably made of an oxide of the element, and may be a complex oxide. As such an inorganic carrier, for example, silica particles (mesoporous silica, silicalite), silica-alumina particles, alumina particles (active alumina particles), carbon particles, activated carbon (coconut shell, phenol resin, basic, etc.), Zeolite particles (Y type, A type, mordenite type, ZSM-5 type, etc., which may be natural or synthetic), ceria (cerium oxide) particles, kaolin particles, smectite particles, vermiculite particles, mica flakes, titania and zirconia Can be mentioned.

  Further, the shape of the carrier is not particularly limited, and may be, for example, spherical or indefinite.

The average particle diameter (median diameter) of the carrier is not particularly limited, but is preferably 10 nm to 100 mm, more preferably 12 nm to 50 mm, more preferably 15 nm to 10 mm, and further preferably 20 nm to 5 mm.
Here, the average particle diameter of the carrier is adjusted so that the measurement object (carrier) is added to the sodium hexametaphosphate aqueous solution and dispersed by ultrasonic dispersion and stirring to adjust the transmittance to 70 to 90%. It means a value calculated by measuring the particle size distribution using a known laser scattering method (for example, HORIBA LA-950V2).

Although the specific surface area of the support is not particularly limited, it is preferably 1~2000m ² / g, more preferably 5~1800m ² / g, more preferably from 10~1500m ² / g.
In addition, the specific surface area of a support | carrier here shall mean the value obtained by measuring by nitrogen adsorption method [3] (BET method) similarly to the specific surface area of the covering particle | grains of this invention mentioned above.

  The supported catalyst of the present invention is such that the coated particles of the present invention are supported on at least a part of the surface of such a carrier.

  The amount of the metal core particles contained in the supported catalyst of the present invention is not particularly limited, but is preferably 0.01 to 100 parts by mass, and 0.1 to 50 parts by mass with respect to 100 parts by mass of the carrier. More preferably, it is 0.5-20 mass parts, More preferably, it is 1-10 mass parts. This is because if the amount of the metal core particles is too small relative to the support, the catalytic ability tends to be low, and conversely if too large, the catalytic ability tends not to be high for an increase in cost.

  Here, the amount of the metal core particles contained in the supported catalyst of the present invention is such that the supported catalyst of the present invention is calcined at 600 ° C., the residue is melted with an alkaline melting agent, and then dissolved in 28% by mass hydrochloric acid or nitric acid aqueous solution. Then, after the obtained solution is diluted with pure water, the content of the components constituting the metal core particles is measured and obtained using an ICP inductively coupled plasma emission spectrometer (for example, SPS1200A, manufactured by Seiko Electronics Co., Ltd.). Shall. When the same element is contained in the metal core particle and the porous silica oligomer layer, the supported catalyst of the present invention is subjected to surface analysis (element distribution analysis) by EDX, and the element in the metal core particle and the porous silica oligomer layer. The content ratio of the components constituting the metal core particles is calculated from the obtained content ratio and the composition of each component using the above ICP inductively coupled plasma emission spectrometer. .

Further, in the supported catalyst of the present invention, the coated particles of the present invention, a unit area of the carrier (1 m ²⁾ per preferably being ² carries 10 ² to 10 ¹⁷ / m, 10 ³ to 10 ¹⁵ atoms / More preferably, m ^{2 is} supported. This is because if the amount of the coated particles of the present invention is too small relative to the support, the catalytic ability tends to be low, and conversely if too large, the catalytic ability tends not to be high for an increase in cost.

  Here, the number of the coated particles of the present invention supported on the carrier was photographed with a scanning electron microscope at a magnification of 300,000 times, and from the photograph obtained by the naked eye, or The number of carrying is measured using a reader.

Further, the specific surface area of the supported catalyst of the present invention is not particularly limited, is preferably 1~2000m ² / g, more preferably 5~1800m ² / g, a 10~1500m ² / g Is more preferable.
Here, the specific surface area of the supported catalyst of the present invention means a value obtained by measurement by the nitrogen adsorption method [3] (BET method) in the same manner as the specific surface area of the coated particles of the present invention described above. To do.

The average particle diameter (median diameter) of the supported catalyst of the present invention is not particularly limited, but is preferably 10 nm to 100 mm, more preferably 12 nm to 50 mm, more preferably 15 nm to 10 mm, and further preferably 20 nm to 5 mm.
Here, the average particle diameter of the supported catalyst of the present invention is such that the measurement object (supported catalyst of the present invention) is added to a sodium hexametaphosphate aqueous solution and dispersed by ultrasonic dispersion and stirring, and the transmittance is 70 to 90%. After the adjustment, the value calculated by measuring the particle size distribution using a conventionally known laser scattering method (for example, HORIBA LA-950V2) is meant.

  The wettability of the surface of the supported catalyst of the present invention is affected by the wettability of the coated particles of the present invention.

Next, the manufacturing method of the covering particle | grains of this invention is demonstrated.
Although the manufacturing method of the coated particle of this invention is not specifically limited, It is preferable to manufacture with the suitable manufacturing method of the coated particle of this invention demonstrated below.
The preferred method for producing coated particles of the present invention includes a colloid preparation step for obtaining a colloidal solution in which metal core particles are dispersed, and a hydrolyzable organosilicon compound represented by the above formula (I) by hydrolysis and polycondensation. An oligomer forming step for obtaining a solution containing a system precursor, a coating step for mixing the colloidal solution and a solution containing the silica precursor to obtain a dispersion liquid (X) containing precursor-coated particles, This is a method for producing porous silica oligomer-coated particles, comprising a pore forming step of separating the solvent and solid content contained in the dispersion (X) to obtain porous silica oligomer-coated particles.

<Colloid adjustment process>
First, the colloid adjustment step in the preferred method for producing coated particles of the present invention will be described.
The colloid adjusting step is a step of obtaining a colloid solution in which the metal core particles are dispersed.
For example, a colloidal solution in which metal core particles are dispersed can be obtained by reducing specific metal ions in the solution. Moreover, as a method of reducing a specific metal ion in a solution, a method of bringing a specific metal ion and a reducing agent into contact with each other in a solution can be mentioned. Here, the specific metal ion can be obtained by dissolving a metal compound (metal salt or the like) constituting the metal core particle in a solvent.
Moreover, when making a specific metal ion and a reducing agent contact in a solution, it is preferable to add a complexing stabilizer together in a solution. This is because the particles obtained after the reduction can be made uniform and stable.

Examples of such metal compounds (metal salts and the like) include palladium chloride, palladium nitrate, palladium sulfate, palladium citrate, and palladium acetate. When such a compound is dissolved in a solvent, palladium ions are obtained as specific metal ions, and a colloidal solution in which metal core particles containing palladium are dispersed is obtained by bringing this ion into contact with a reducing agent.
In addition, chloroplatinic acid, potassium platinum (IV) chloride, sodium chloroplatinum (IV), potassium tetranitroplatinum (II), sodium hexahydroxoplatinum (IV) hydrate as metal compounds (metal salts, etc.) , Dinitrodiammine platinum nitrate, dinitrodiammine platinum ammonia, tetraamminedichloroplatinum hydrate. When such a compound is dissolved in a solvent, platinum ions are obtained as specific metal ions, and a colloidal solution in which metal core particles containing platinum are dispersed is obtained by bringing this ion into contact with a reducing agent.
Moreover, silver nitrate and silver sulfate are mentioned as a metal compound (metal salt etc.). When such a compound is dissolved in a solvent, silver ions are obtained as specific metal ions, and a colloidal solution in which metal core particles containing silver are dispersed is obtained by bringing this into contact with a reducing agent in a solution.
Examples of metal compounds (metal salts and the like) include chloroauric acid, sodium gold sulfite, potassium gold cyanide, and sodium gold cyanide. When such a compound is dissolved in a solvent, gold ions are obtained as specific metal ions, and a colloidal solution in which metal core particles containing gold are dispersed is obtained by bringing this into contact with a reducing agent.
Moreover, copper chloride, copper sulfate, copper nitrate is mentioned as a metal compound (metal salt etc.). When such a compound is dissolved in a solvent, copper ions are obtained as specific metal ions, and a colloidal solution in which metal core particles containing copper are dispersed is obtained by bringing this into contact with a reducing agent.
Furthermore, ferric sulfate and ferrous acetate are mentioned as a metal compound (metal salt etc.). When such a compound is dissolved in a solvent, iron ions are obtained as specific metal ions, and a colloidal solution in which metal core particles containing iron are dispersed is obtained by bringing this into contact with a reducing agent.

  In addition, the solvent used for dissolving the metal compound (metal salt or the like) constituting the metal core particle in order to obtain the metal ion is not particularly limited as long as it does not react with the compound. , Water, alcohols, ketones, amides, ethers, glycol ethers, glycol ether acetates, esters, aromatic hydrocarbons, aliphatic hydrocarbons, halogenated hydrocarbons, sulfoxides, pyrrolidones Etc.

  Examples of the reducing agent include alcohol, hydrazine, formic acid, formaldehyde, hydroquinone, perchloric acid, ferrous sulfate, sodium borohydride, hydrogen peroxide, and potassium permanganate.

By adding such a reducing agent to a solution containing metal ions, the metal ions and the reducing agent can be brought into contact with each other in the solution. Alternatively, the metal ion and the reducing agent can be brought into contact with each other in the solution by dissolving the reducing agent in a solvent in advance to form a solution and mixing the solution with a solution containing metal ions. The solvent in which the reducing agent is dissolved in advance may be the same as the solvent in which the metal compound (metal salt or the like) that constitutes the metal core particle is dissolved.
Metal ions are preferably reduced by adding a reducing agent to the solution while stirring the solution.

  In addition, the amount ratio of the metal ion to the reducing agent is not particularly limited, but the reducing agent is preferably 10 parts by mass to 500 parts by mass with respect to 100 parts by mass of the metal ion, and 50 to 300 parts by mass. More preferably.

  Moreover, it is preferable to add a dispersant or a surfactant (for example, polyvinyl pyrrolidone, aminosilane, polycarboxylic acid, organic acid, etc.) as necessary after contacting the metal ion with the reducing agent in the solution. . This is because the metal core particles hardly aggregate.

In addition, it is preferable to remove the unreacted metal ions and the reducing agent by bringing the metal ions and the reducing agent into contact with each other in the solution and then washing them using an ultrafilter or the like.
Further, it is preferable to contact a metal ion and a reducing agent in a solution, add an acid such as hydrochloric acid to dissolve excess salt, and then desalinate using an ion exchange resin or the like.

Further, when the metal ion and the reducing agent are brought into contact with each other in an aqueous solution, preferably, after further washing with an ultrafilter and desalting with an ion exchange resin or the like as described above, a solvent ( It is preferable to substitute water) with an organic solvent. This is because a porous silica oligomer layer is easily formed on the surface of the metal core particles in the subsequent coating step.
As the organic solvent, methanol, ethanol, propanol, 2-propanol (IPA), alcohols such as butanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol isopropoxy b pills ether, propylene glycol monomethyl ether , ethers such as profile propylene glycol monoethyl ether; acetone, methyl ethyl ketone, ketones such as methyl isobutyl ketone.
Among these, the use of alcohols such as methanol, ethanol, 2-propanol (IPA) is preferable because the metal core particles are less likely to agglomerate and tend to be stable.
As a replacement method, a conventionally known method such as a distillation method, an ultrafiltration membrane method, or a rotary evaporator method can be employed.
The concentration of the solid content in the obtained colloidal solution is preferably 0.5 to 40% by mass, and more preferably 1.0 to 30% by mass.

<Oligomer formation process>
Next, the oligomer formation process in the suitable manufacturing method of the covering particle | grains of this invention is demonstrated.
The oligomer forming step is a step of obtaining a solution containing a silica precursor by hydrolyzing and polycondensing the hydrolyzable organosilicon compound represented by the formula (I).

For example, the hydrolyzable organosilicon compound represented by the formula (I) can be added to a solvent to obtain a solution containing a silica-based precursor.
Here, the solvent is not particularly limited, but water or an organic solvent can be used, and a mixed solvent of water and an organic solvent is preferably used. Alcohol (ethanol etc.) etc. can be used as an organic solvent.
The hydrolyzable organosilicon compound is preferably added to the solvent together with an acid catalyst or an alkali catalyst. Examples of the acid catalyst include hydrochloric acid and nitric acid. When an acid catalyst is used, there is a tendency that a silica-based precursor having a form in which siloxane bonds are linearly connected is formed. In addition, when an alkali catalyst is used, a silica-based precursor having an aspect in which a siloxane bond is present so that one molecule (for example, a hydrolysis product of a hydrolyzable organosilicon compound) and another molecule are connected in a network form. There is a tendency to form. In the preferred method for producing coated particles of the present invention, it is preferable to use an acid catalyst.
In addition, it is preferable to add the hydrolyzable organosilicon compound represented by the formula (I) to the solvent, preferably add an acid catalyst or an alkali catalyst, and then warm and / or stir. This is because a silica-based precursor having a preferable molecular weight tends to be obtained.

By doing so , it is considered that a solution containing a silica-based precursor is obtained by hydrolysis and polycondensation based on the formulas (II) to (IV).
Wherein the molecular weight of the silica-based precursor preferably has a molecular weight measured by GPC (polystyrene equivalent) is 50 0~ 30000g / mol, is preferably 1000~20000g / mol, that is 2000~4500g / mol Further preferred. This is because there is a tendency that pores having a desired size are easily formed in the porous silica oligomer layer.
Here, GPC measurement is a molecular weight measurement method using gel permeation chromatography. Specifically, the synthesized silica oligomer is diluted to about 0.01 to 1% by mass with THF (tetrahydrofuran), and the elution solvent is used. As a standard substance using a GPC apparatus in which THF is developed.

  Moreover, it is preferable that pH of the solution containing the obtained silica type precursor is 1-8, It is more preferable that it is 1.5-7, It is further more preferable that it is 2-6.

  Moreover, it is preferable to remove the used acid catalyst or alkali catalyst from the solution containing the silica-based precursor. For example, it can be removed using an ion exchange resin.

  The concentration of the solid content in the solution containing the silica-based precursor is preferably 0.1 to 10% by mass, and more preferably 1 to 7% by mass.

<Coating process>
Next, the coating step in the preferred method for producing coated particles of the present invention will be described.
The coating step is a step of obtaining a dispersion liquid (X) containing precursor-coated particles by mixing the colloidal solution and a solution containing the silica-based precursor.

  The colloidal solution and the solution containing the silica-based precursor are preferably mixed while heating. For example, if the colloidal solution at room temperature is added little by little while heating the solution containing the silica-based precursor, the two solutions can be mixed while heating. Although temperature is not specifically limited here, It is preferable that it is 5-90 degreeC, and it is more preferable that it is 10-60 degreeC.

Moreover, it is preferable to mix two solutions little by little, stirring.
For example, the colloidal solution is preferably added to the solution containing the silica-based precursor little by little over several hours to several tens of hours (for example, about 1 to 24 hours) with stirring and mixed.

  The mixing ratio of the two solutions is not particularly limited, but the ratio of the solid content contained in the solution containing the silica-based precursor to be mixed to the mass of the solid content contained in the colloidal solution to be mixed (including the silica-based precursor) The mass of the solid content contained in the solution / the mass of the solid content contained in the colloid solution) is preferably 0.1 to 5000, more preferably 0.5 to 3000, and preferably 1 to 2000. Is more preferable, it is more preferable that it is 1-1000, it is more preferable that it is 1-500, and it is further more preferable that it is 1-100. Within such a range, the activity of the supported catalyst of the present invention in which the coated particles of the present invention are supported on a carrier is higher, and even when used, the activity is maintained for a longer period, which is preferable.

  By such a coating step, it is possible to obtain a dispersion liquid (X) including precursor-coated particles in which a film made of the silica-based precursor is formed on the surface of the metal core particles included in the colloidal solution.

<Pore forming step>
Next, the pore forming step in the production method of the present invention will be described.
In the pore forming step, the solvent and solid content contained in the dispersion (X) are separated.

The method for separating the solvent contained in the dispersion liquid (X) is not particularly limited, and for example, a conventionally known solid-liquid separation method can be applied. Further, for example, the dispersion liquid (X) can be dried by placing it in a dryer to separate the solvent contained in the dispersion liquid (X).
In the pore forming step, it is preferable to separate the solvent from the dispersion liquid (X) by drying the dispersion liquid (X) under reduced pressure.

Thus, when the dispersion liquid (X) is dried or the like to separate the solvent, the precursor coating (coating containing a silica-based precursor) on the surface of the metal core particles contracts in the process. And the pore is formed in the film.
When drying the dispersion liquid (X), the inventor tends to decrease the pore diameter when the drying temperature is high, and conversely, when the drying temperature is low, the pore diameter tends to increase. I found. And it discovered that the average pore diameter of the pore in the porous silica type oligomer covering particle obtained was adjusted by optimizing drying temperature. Here, the drying temperature is preferably 30 to 500 ° C, and more preferably 50 to 400 ° C.

Next, the manufacturing method of the supported catalyst element of this invention is demonstrated.
The method for producing the supported catalyst of the present invention is not particularly limited, but it is preferably produced by the preferred method for producing the supported catalyst of the present invention described below.
The preferred production method of the supported catalyst of the present invention comprises a colloid preparation step for obtaining a colloidal solution in which metal core particles are dispersed, and a hydrolyzable organosilicon compound represented by the above formula (I) by hydrolysis and polycondensation. An oligomer forming step for obtaining a solution containing a system precursor, a coating step for mixing the colloidal solution and a solution containing the silica precursor to obtain a dispersion liquid (X) containing precursor-coated particles, The addition step of adding the carrier to the dispersion (X) to obtain the dispersion (Y) and the solvent and solids contained in the dispersion (Y) are separated, so that the porous silica oligomer-coated particles become the carrier And a supporting process for obtaining a supported catalyst.

  The colloid adjustment step, the oligomer formation step and the coating step in the preferred production method of the supported catalyst of the present invention may be the same as those provided in the above preferred production method of the coated particles of the present invention.

<Addition process>
The addition step in the preferred production method of the supported catalyst of the present invention will be described.
In the addition step, the carrier is added to the dispersion (X) obtained in the coating step.
The addition amount of the carrier is not particularly limited, but the metal core particles contained in the dispersion (X) are preferably in an addition amount of 0.01 to 100 parts by mass with respect to 100 parts by mass of the carrier. The addition amount is more preferably 0.1 to 50 parts by mass, the addition amount is more preferably 0.5 to 20 parts by mass, and the addition amount is 1 to 10 parts by mass. Further preferred.

<Supporting process>
Next, the supporting step in the preferred production method of the supported catalyst of the present invention will be described.
This supporting step is similar to the pore forming step in the preferred method for producing coated particles of the present invention.
In the supporting step in the preferred production method of the supported catalyst of the present invention, the solvent in the dispersion (Y) is separated from the solid content.

The method for separating the solvent contained in the dispersion (Y) is not particularly limited, and for example, a conventionally known solid-liquid separation method can be applied. For example, the dispersion (Y) can be dried by placing it in a dryer, and the solvent can be separated from the dispersion (Y).
In the supporting step, it is preferable to separate the solvent from the dispersion liquid (Y) by drying the dispersion liquid (Y) under reduced pressure.
When the solvent is separated from the dispersion liquid (Y), a porous silica oligomer-coated particle supported on a support (supported catalyst of the present invention) can be obtained as a solid content.

In this way, when the dispersion liquid (Y) is dried or the like to separate the solvent, the precursor coating on the surface of the metal core particles contracts in the process. And the pore is formed in the film.
When drying the dispersion liquid (Y), the inventor tends to decrease the pore diameter when the drying temperature is high, and conversely tends to increase the pore diameter when the drying temperature is low. I found. And it discovered that the average pore diameter of the pore in the porous silica type oligomer covering particle obtained was adjusted by optimizing drying temperature. Here, the drying temperature is preferably 30 to 500 ° C, and more preferably 50 to 400 ° C.

  Examples of the present invention will be described below. The present invention is not limited to these examples.

<Measurement method and evaluation method>
Various measurement methods and evaluation methods performed in Examples and Comparative Examples will be described.

[1] Method for measuring average particle diameter (median diameter) of metal core particles The average particle diameter was measured by an image analysis method. That is, using a scanning electron microscope (S-5500, manufactured by Hitachi, Ltd.), a sample (metal core particles, porous silica oligomer-coated particles or supported catalyst) was photographed at a magnification of 300,000 times, and obtained. 100 metal core particles were arbitrarily selected from the photograph, each projected area equivalent circle diameter was measured to obtain a particle size distribution, and an average particle diameter (median diameter) was calculated therefrom.

[2] Method for measuring thickness of porous silica oligomer layer Using a scanning electron microscope (S-5500, manufactured by Hitachi, Ltd.), a sample (porous silica oligomer-coated particles) was photographed at a magnification of 300,000 times. Then, arbitrarily select 100 porous silica oligomer-coated particles from the photograph obtained, and measure the thickness of the porous silica oligomer layer in each porous silica oligomer-coated particle several times and average one of them. The thickness of the porous silica oligomer layer in the porous silica oligomer-coated particles was taken as the thickness of the porous silica oligomer layer in the sample (group of porous silica oligomer-coated particles) by simply averaging the 100 data. .

[3] Measuring method of average value of pore diameter of porous silica oligomer layer Fine pore size of porous silica oligomer layer is measured by nitrogen adsorption method [1] using a pore distribution measuring device (BELSORP mini, manufactured by Nippon Bell Co., Ltd.). The average value of pore diameter (average pore diameter) was measured.
The nitrogen adsorption method [1] is the following method.
First, the dried measurement object (0.2 g) is placed in a measurement cell as a sample, degassed in a nitrogen gas stream at 250 ° C. for 40 minutes, and then the sample is treated with 30 vol% nitrogen and helium. The liquid nitrogen temperature was maintained in a 70% by volume mixed gas stream, and nitrogen was adsorbed on the sample to obtain a nitrogen adsorption / desorption isotherm. Then, using the obtained nitrogen adsorption / desorption isotherm, a BJH (Barret-Joyner-Halenda) method is used to obtain a pore size distribution curve of the sample, and the mesopores (pores on the particle surface) side appearing on the curve and Of the peaks on the macropore (interparticle pore) side, the mesopore-side peak pore diameter was determined as the average pore diameter.

[4] Method for measuring pore volume of porous silica oligomer layer Pores of porous silica oligomer layer by a nitrogen adsorption method [2] using a pore distribution measuring device (BELSORP mini, manufactured by Bell Japan) The volume of was measured.
The nitrogen adsorption method [2] is the following method.
First, the dried measurement object (0.2 g) is placed in a measurement cell as a sample, degassed in a nitrogen gas stream at 250 ° C. for 40 minutes, and then the sample is treated with 30 vol% nitrogen and helium. The liquid nitrogen temperature was maintained in a 70% by volume mixed gas stream, and nitrogen was adsorbed on the sample to obtain a nitrogen adsorption / desorption isotherm. Then, the integrated value of the mesopore side portion in the IV hysteresis curve defined by IUPAC, where the value of the relative pressure P / P _{0 in} the obtained nitrogen adsorption / desorption isotherm appears in the range of 0.4 to 1.0, This was obtained as the pore volume.

[5] Method for Measuring Specific Surface Area of Porous Silica Oligomer Coated Particles Porous silica oligomer by nitrogen adsorption method [3] (BET method) using a surface area measuring device (manufactured by Yuasa Ionics Co., Ltd., Multisorb type 12) The specific surface area of the coated particles was measured.
The nitrogen adsorption method [3] is the following method.
First, a dried measurement object (porous silica oligomer-coated particles) (0.2 g) is placed in a measurement cell as a sample, and degassed at 250 ° C. for 40 minutes in a nitrogen gas stream. The sample was kept at a liquid nitrogen temperature in a mixed gas stream of 30% by volume of nitrogen and 70% by volume of helium, and nitrogen was adsorbed on the sample by equilibrium. Next, the sample temperature was gradually raised to room temperature while flowing the mixed gas, and the amount of nitrogen desorbed during that time was detected, and the specific surface area of the sample was measured.

[6] Method for measuring wettability (contact angle) of porous silica oligomer-coated particles After drying 1 g of porous silica oligomer-coated particles at 200 ° C., they are put into a cell having a diameter of 1 cm and a height of 5 cm, and a load of 50 kgf Then, a molded product was obtained by pressing, and a drop of water was dropped on the surface of the obtained molded product, and the contact angle was measured.

[7] Catalyst performance evaluation method (measurement of catalyst activity and life)
A double-type glass reaction tube in which another glass tube with an inner diameter of 21 mm was inserted into a glass tube with an inner diameter of 30 mm was prepared, and the supported catalyst was filled in the inner glass tube so as to block a part of the flow path. . The mass of the supported catalyst filled here was such that the mass of the metal core particles contained therein was 0.002 g.
Warm water at 40 ° C. was circulated between the inner glass tube and the outer glass tube of such a double glass reaction tube to keep the temperature in the inner glass tube constant. Thereafter, the mixed gas was introduced into the inner glass reaction tube from one end at 422 ml / min. Then, after contact with the supported catalyst filled, the concentration of ethylene (C ₂ H ₄₎ and ethane (C ₂ H ₆₎ was measured by gas chromatography in the exhaust gas discharged from the other end. The measurement was carried out once per hour and for a maximum of 48 hours. The mixed gas introduced into the inner glass reaction tube is N ₂ : H ₂ : C ₂ H ₂ = 400: 10: 12 (volume ratio).
Then, to determine the production rate from the concentration of ethylene (C ₂ H ₄₎ and ethane in the exhaust gas was measured (C ₂ H _6). The production rate is obtained by the following equation, and the initial production rate obtained from this equation (the production rate measured when the composition of the exhaust gas is stabilized after a few minutes have passed since the introduction of the mixed gas) is defined as the catalyst activity. The time when the production rate decreased by 3% with respect to the catalyst activity was defined as the life.
Production rate = total amount of moles of ethylene and ethane in the exhaust gas per hour (mol / min) / mol amount of acetylene in the mixed gas per hour (mol / min) × 100

<Method for adjusting metal core particles>
Next, a method for preparing a colloidal solution in which metal core particles are dispersed will be described.

[Synthesis Example 1]
Preparation Method of Pd Colloid Solution 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 mixed well to obtain a dispersion in which Pd particles were dispersed. The obtained dispersion was washed (desalted, etc.) using an ultrafilter (manufactured by ADVANTEC, Ultrafilter Q0500) and concentrated to obtain a Pd dispersion having a Pd concentration of 3% by mass.
The obtained Pd dispersion was diluted about 1000 times, a part of the Pd particles was placed on a collodion film and dried, and the average particle diameter, specific surface area and contact angle were measured by the above-described methods. As a result, the average particle diameter was 2 nm, the specific surface area was 273 m ² / g, and the contact angle was 56 degrees. It was confirmed by observation with a scanning electron microscope that the Pd particles were spherical.
Next, 1 g of 1% by volume hydrochloric acid was added to 100 g of the obtained Pd dispersion, and after stirring for 1 hour, 10 g of an anion exchange resin (manufactured by Mitsubishi Chemical Corporation, SANUPC) was added for desalting. After desalting, coarse particles were cut using a centrifuge (G = 8000), and the dispersion medium was replaced from water to methanol using an ultrafiltration membrane to obtain a colloidal solution of Pd. .
Thereafter, the Pd concentration was measured using an ICP inductively coupled plasma optical emission spectrometer SPS1200A (manufactured by Seiko Electronics Co., Ltd.). And the Pd colloidal solution adjusted so that Pd density | concentration might be 2.5 mass% was obtained.
The physical properties and the like of the obtained colloid solution are shown in Table 1.

<Example 1>
To 100 g of ethanol, 34.7 g of normal ethyl silicate, 20 g of pure water and 0.1 g of 61% by volume nitric acid were added, and the resulting solution was slowly stirred for 90 minutes while being kept at 50 ° C. A solution (i) containing a precursor was obtained.
Next, after removing nitric acid contained in the obtained solution (i) using an anion exchange resin, ethanol is added to adjust the solid content concentration to 5% by mass, and a solution containing a silica-based precursor ( ii) was obtained. The pH of the obtained solution (ii) was 4.5, and the molecular weight (polystyrene conversion) by GPC measurement (gel permeation chromatography, manufactured by Shimadzu Corp., Promince) was 2800 g / mol.
Next, 4 g of the Pd colloid solution obtained in Synthesis Example 1 was gradually added to 24 g of the solution (ii) over 24 hours to obtain a dispersion (X) in which the precursor-coated particles were dispersed. Here, a solution obtained by adding at least a part of the Pd colloid solution to the solution (ii) is also referred to as a reaction solution. While the solution (ii) was added, the reaction solution was kept at 50 ° C.
Then, a part of the obtained solution (ii) is diluted about 1000 times, placed on a collodion membrane, separated by drying under reduced pressure at 105 ° C. for 24 hours, and the porous silica oligomer-coated particles are separated by the above-described method. The thickness of the porous silica oligomer layer, the average value of the pore diameter (average pore diameter), the pore volume, the specific surface area, the contact angle, and the average particle diameter of the metal core particles were measured.
The measurement results are shown in Table 1.

Next, activated carbon (manufactured by Ajinomoto Fine Techno Co., Ltd., trade name: CL-K, particle size: 0.5 mm to 1.7 mm, iodine adsorption amount 1,550 mg / g) is added to the dispersion (X), and 10 The resulting dispersion (Y) was dried under reduced pressure at 105 ° C. for 24 hours to obtain a supported catalyst. The supported catalyst is one in which porous silica oligomer-coated particles are supported on activated carbon. The amount of activated carbon added to the dispersion (X) was adjusted so that the supported amount (content) of the metal core particles in the supported catalyst was 1.0% by mass.
Further, the performance of the obtained supported catalyst was evaluated based on the above-described catalyst performance evaluation method. Further, the performance of the supported catalyst calcined at 500 ° C. for 3 hours was similarly evaluated. Further, the average particle diameter of the metal core particles was measured for the supported catalyst calcined at 500 ° C. for 3 hours.
The measurement results are shown in Table 1.

<Example 2>
In Example 1, 4 g of Pd colloidal solution was added to 24 g of the solution (ii) to obtain a dispersion (X). In Example 2, 24 g of Pd colloidal solution was gradually added to 90 g of the solution (ii). A dispersion (X) in which the precursor-coated particles were dispersed by adding over time was obtained.
The other operations were performed in the same manner as in Example 1 and the same measurement was performed.
The measurement results are shown in Table 1.

<Example 3>
In Example 1, 4 g of Pd colloidal solution was added to 24 g of the solution (ii) to obtain a dispersion (X). In Example 3, 4 g of Pd colloidal solution was added to 200 g of the solution (ii) little by little. A dispersion (X) in which the precursor-coated particles were dispersed by adding over time was obtained.
The other operations were performed in the same manner as in Example 1 and the same measurement was performed.
The measurement results are shown in Table 1.

<Example 4>
In Example 1, the dispersion (Y) was dried under reduced pressure at 105 ° C. for 24 hours to obtain a supported catalyst. In Example 4, the dispersion (Y) was dried at 200 ° C. for 24 hours under reduced pressure to carry the supported catalyst. A catalyst was obtained.
The other operations were performed in the same manner as in Example 1 and the same measurement was performed.
The measurement results are shown in Table 1.

<Example 5>
In Example 1, the dispersion (Y) was dried under reduced pressure at 105 ° C. for 24 hours to obtain a supported catalyst. In Example 5, the dispersion (Y) was dried at 50 ° C. for 24 hours under reduced pressure to carry the supported catalyst. A catalyst was obtained.
The other operations were performed in the same manner as in Example 1 and the same measurement was performed.
The measurement results are shown in Table 1.

<Example 6>
In Example 1, 34.7 g of normal ethyl silicate, 20 g of pure water and 0.1 g of 61 volume% nitric acid were added to 100 g of ethanol, and the resulting solution was slowly stirred for 90 minutes while being kept at 50 ° C. Thus, a solution (i) containing a silica-based precursor was obtained. In Example 6, 9.8 g of methyl silicate dimer (manufactured by Tama Chemical Co., Ltd., methyl silicate 51), 20 g of pure water and 61% by volume of ethanol were added to 100 g of ethanol. Nitric acid (0.1 g) was added, and the resulting solution was slowly stirred for 90 minutes while being kept at 50 ° C. and aged to obtain a solution (i) containing a silica-based precursor.
The other operations were performed in the same manner as in Example 1 and the same measurement was performed.
In addition, pH of the solution (ii) obtained by such a method was 4.8, and the molecular weight (polystyrene conversion) by GPC measurement was 4500 g / mol.
The measurement results are shown in Table 1.

<Example 7>
In Example 1, 34.7 g of normal ethyl silicate, 20 g of pure water and 0.1 g of 61 volume% nitric acid were added to 100 g of ethanol, and the resulting solution was slowly stirred for 90 minutes while being kept at 50 ° C. Thus, a solution (i) containing a silica-based precursor was obtained. In Example 7 , in 100 g of ethanol, 8.7 g of normal ethyl silicate, 10 g of methyltrimethoxysilane, 20 g of pure water, and 0.1 g of nitric acid containing 61% by volume. Was added, and the resulting solution was slowly stirred for 90 minutes while being kept at 50 ° C. and aged to obtain a solution (i) containing a silica-based precursor.
The other operations were performed in the same manner as in Example 1 and the same measurement was performed.
In addition, pH of the solution (ii) obtained by such a method was 5.5, and the molecular weight (polystyrene conversion) by GPC measurement was 2000 g / mol.
The measurement results are shown in Table 1.

<Comparative Example 1>
To 100 g of a solution obtained by adding methanol to the Pd colloid solution obtained in Synthesis Example 1 and diluting to 0.1% by mass, the same activated carbon as that used in Example 1 was added and stirred for 10 minutes. Here, the amount of activated carbon added was adjusted so that the supported amount (content) of the metal core particles in the supported catalyst was 1.0% by mass. And the obtained dispersion liquid (Y) was dried under reduced pressure at 105 degreeC for 24 hours, and the supported catalyst was obtained. The supported catalyst is one in which Pd particles are supported on activated carbon.
And about the supported catalyst obtained in this way, the same measurement as Example 1 was performed.
The measurement results are shown in Table 1.

From the results of the catalyst performance evaluation in Table 1, it can be seen that the supported catalysts in all Examples have high activity and long life even after calcination at 500 ° C. Moreover, when the average particle diameter of the metal core particle before and behind 500 degreeC baking is contrasted, it turns out that there is no change.
In contrast, the supported catalyst in Comparative Example 1 had a high activity before calcination at 500 ° C., but a low activity after calcination at 500 ° C. Further, the lifetime was short even before baking at 500 ° C., and extremely short after baking at 500 ° C. Moreover, in the case of the comparative example 1, the average particle diameter of the metal core particle after 500 degreeC baking became large 75 times compared with before 500 degreeC baking. This is presumably because the metal core particles aggregated because Comparative Example 1 does not have the porous silica oligomer layer provided in the supported catalysts of Examples 1 to 7.

Claims (10)

Having a metal core particle and a porous silica oligomer layer on at least a part of its surface;
The porous silica oligomer layer comprises a silica-based compound having at least one siloxane bond;
The average thickness of the porous silica oligomer layer is more than 2 nm and not more than 20 nm,
Porous silica oligomer-coated particles , wherein the porous silica oligomer layer has an average pore diameter of 0.8 to 4.0 nm. The porous silica oligomer-coated particles according to claim 1, wherein the pore volume is 0.01 to 0.5 ml / g. The porous silica oligomer-coated particles according to claim 1 or 2 , having a specific surface area of 100 to 1000 m ² / g. The porous silica oligomer-coated particles according to any one of claims 1 to 3 , wherein the silica compound has a molecular weight (molecular weight measured by gel permeation chromatography using polystyrene as a standard substance) of 500 to 30000 g / mol. Wherein the metal core particles, fourth period transition elements, 5th period transition elements, platinum, gold, as a main component at least one selected from the group consisting of osmium, and iridium, according to any one of claims 1 to 4 Porous silica oligomer-coated particles. Supported catalyst porous silica oligomer-coated particles according to any one of claims 1 to 5 is carried on the surface of the carrier. A colloid preparation step for obtaining a colloidal solution in which metal core particles are dispersed;
An oligomer forming step of obtaining a solution containing a silica-based precursor by hydrolyzing and polycondensing a hydrolyzable organosilicon compound represented by the following formula (I);
A coating step of mixing the colloid solution and a solution containing the silica-based precursor to obtain a dispersion (X) containing precursor-coated particles;
A porous silica oligomer coating according to any one of claims 1 to 5 , comprising a pore forming step of separating the solvent and solid content contained in the dispersion (X) to obtain porous silica oligomer coated particles. A method for producing porous silica oligomer-coated particles, in which particles are obtained.
R ¹ _a Si (OR ² ) _4-a Formula (I)
Here, R ¹ represents a hydrogen atom, a halogen atom, an alkyl group, a halogenated alkyl group, a vinyl group, an aryl group or an acrylic group, and R ² represents a hydrogen atom, an alkyl group, a halogenated alkyl group, a vinyl group or an aryl group. Represents an acrylic group or —C ₂ H ₄ OC _n H _{2n + 1} (n = 1 to 4), and a is an integer of 1 to 3. A colloid preparation step for obtaining a colloidal solution in which metal core particles are dispersed;
Tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, tetraoctylsilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, methyltriisopropoxysilane, vinyltrimethoxysilane, phenyltrimethoxy An oligomer forming step of hydrolyzing and polycondensing at least one selected from the group consisting of silane and dimethyldimethoxysilane to obtain a solution containing a silica-based precursor;
A coating step of mixing the colloid solution and a solution containing the silica-based precursor to obtain a dispersion (X) containing precursor-coated particles;
A porous silica oligomer coating according to any one of claims 1 to 5 , comprising a pore forming step of separating the solvent and solid content contained in the dispersion (X) to obtain porous silica oligomer coated particles. A method for producing porous silica oligomer-coated particles, in which particles are obtained. A colloid preparation step for obtaining a colloidal solution in which metal core particles are dispersed;
An oligomer forming step of obtaining a solution containing a silica-based precursor by hydrolyzing and polycondensing a hydrolyzable organosilicon compound represented by the following formula (I);
A coating step of mixing the colloid solution and a solution containing the silica-based precursor to obtain a dispersion (X) containing precursor-coated particles;
An addition step of adding a carrier to the dispersion (X) to obtain a dispersion (Y);
By separating the solvent and the solids contained in the dispersion liquid (Y), and a supporting step of porous silica oligomer-coated particles to obtain a supported catalyst supported on a carrier, according to any one of claims 1 to 5 A method for producing a supported catalyst, in which a supported catalyst in which the porous silica oligomer-coated particles are supported on the surface of the support is obtained.
R ¹ _a Si (OR ² ) _4-a Formula (I)
Here, R ¹ represents a hydrogen atom, a halogen atom, an alkyl group, a halogenated alkyl group, a vinyl group, an aryl group or an acrylic group, and R ² represents a hydrogen atom, an alkyl group, a halogenated alkyl group, a vinyl group or an aryl group. Represents an acrylic group or —C ₂ H ₄ OC _n H _{2n + 1} (n = 1 to 4), and a is an integer of 1 to 3. A colloid preparation step for obtaining a colloidal solution in which metal core particles are dispersed;
Tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, tetraoctylsilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, methyltriisopropoxysilane, vinyltrimethoxysilane, phenyltrimethoxy An oligomer forming step of hydrolyzing and polycondensing at least one selected from the group consisting of silane and dimethyldimethoxysilane to obtain a solution containing a silica-based precursor;
A coating step of mixing the colloid solution and a solution containing the silica-based precursor to obtain a dispersion (X) containing precursor-coated particles;
An addition step of adding a carrier to the dispersion (X) to obtain a dispersion (Y);
By separating the solvent and the solids contained in the dispersion liquid (Y), and a supporting step of porous silica oligomer-coated particles to obtain a supported catalyst supported on a carrier, according to any one of claims 1 to 5 A method for producing a supported catalyst, in which a supported catalyst in which the porous silica oligomer-coated particles are supported on the surface of the support is obtained.