WO2019044584A1 - Nucleus hydrogenation reaction catalyst - Google Patents

Abstract

Provided is a nucleus hydrogenation reaction catalyst having a catalytic activity superior to conventional ruthenium catalysts in a nucleus hydrogenation reaction of an aromatic compound in which at least one amino group is bonded to an aromatic ring. Disclosed is a nucleus hydrogenation reaction catalyst used for a nucleus hydrogenation reaction for hydrogenating at least one π bond of an aromatic ring of an aromatic compound in which at least one amino group is bonded to the aromatic ring, the nucleus hydrogenation reaction catalyst comprising a support and catalyst particles supported on the support, wherein: the catalyst particles include Ru (0 valence) and a Ru oxide; and the percentage RRu (atom%) of Ru (0 valence) and the percentage RRuOx (atom%) of the Ru oxide in an analysis region in the vicinity of the surface being measured by X-ray photoelectron spectroscopy (XPS) satisfy the condition of formula (1): 0.60≤{RRuOx/(RRuOx+RRu)}≤0.90.

Description

Nuclear hydrogenation reaction catalyst

The present invention relates to a catalyst used for the nuclear hydrogenation reaction of an aromatic compound in which one or more amino groups are bonded to an aromatic ring.

Conventionally, the nuclear hydrogenation reaction of aromatic compounds has been used to synthesize, for example, a polyamideimide resin as a raw material for highly functional plastic products. And a ruthenium catalyst is known as a catalyst used for the nuclear hydrogenation reaction of an aromatic compound.

For example, Patent Document 1 (Japanese Patent Laid-Open No. 2009-286747) efficiently uses N, N-dimethylcyclohexylamines useful as catalysts for polyurethane foam production, epoxy curing agents, resist release agents, and corrosion inhibitors for steel. The aromatic compound is subjected to a nuclear hydrogenation reaction in the presence of a ruthenium catalyst or the like and hydrogen, and the resulting cyclohexyl compound is converted to the above-mentioned noble metal catalyst, formaldehyde derivative and hydrogen. A process for producing N, N-dimethylcyclohexylamines which are subjected to reductive methylation in the presence is disclosed (Patent Document 1, [Summary]).

More specifically, a ruthenium catalyst in which 5% of ruthenium is supported on alumina (support) is disclosed (Patent Document 1, [0032] Example 1 and [0034] Example 2, etc.).

JP, 2009-286747, A

However, the inventors have found that there is still room for improvement in the conventional ruthenium catalyst as described above from the viewpoint of further improving the conversion of the reactant in the nuclear hydrogenation reaction of an aromatic compound. .

Therefore, the present invention has been made in view of such technical circumstances, and provides a catalyst for nuclear hydrogenation reaction having a catalytic activity superior to that of a conventional ruthenium catalyst in the nuclear hydrogenation reaction of an aromatic compound. The purpose is to

The present inventors focused on the state of ruthenium contained in the catalyst particles supported on the carrier in the ruthenium catalyst used for the nuclear hydrogenation reaction, and conducted intensive studies on the configuration for realizing further improvement of the catalytic activity. The

As a result, the ratio of Ru (zero valence) in the analysis region near the surface of the ruthenium catalyst measured by X-ray photoelectron spectroscopy (XPS) R Ratio of Ru (zero valence) Ru oxide to Ru ratio of _{Ru Rux} The inventors have found that satisfying the following conditions is effective to improve the catalyst activity, and have completed the present invention.

More specifically, the present invention is constituted by the following technical matters.
That is, the present invention
A catalyst for nuclear hydrogenation reaction, which is used in a nuclear hydrogenation reaction for hydrogenating at least one of π-bonds of the aromatic ring in which an aromatic ring has one or more amino groups bonded to the aromatic ring,
A carrier, and catalyst particles supported on the carrier,
The catalyst particles contain Ru (0 valence) and Ru oxide,
The ratio of Ru (zero valence) R _Ru (atom%) and the ratio of Ru oxide R _{RuO x} (atom%) in the analysis region near the surface measured by X-ray photoelectron spectroscopy (XPS) The condition of equation (1) is satisfied,
Provided is a catalyst for nuclear hydrogenation reaction.
0.60 ≦ {R _RuOx / (R _RuOx + R _Ru )} ≦ 0.90 Formula (1)

Here, in the present invention, the ratio of Ru (zero valence) R _Ru (atom%) in the analysis region in the vicinity of the surface of the catalyst for nuclear hydrogenation reaction observed by XPS R _{RuO x} (atom “%)” Is a numerical value calculated under the condition that the sum of these two components is 100%.

In the present invention, by _setting the value of R _RuOx / (R _RuOx + R _Ru ) shown in the above-mentioned formula (1) to be 0.60 or more and 0.90 or less, the nuclear hydrogenation reaction of the present invention The catalyst can exhibit catalytic activity superior to that of conventional ruthenium catalysts in the nuclear hydrogenation reaction of an aromatic compound in which one or more amino groups are bonded to an aromatic ring.

The detailed reason for the excellent catalytic activity of the catalyst for nuclear hydrogenation reaction of the present invention is not sufficiently clarified, but the present inventors think as follows.

That is, since the nuclear hydrogenation reaction catalyst having a structure satisfying the formula (1) has a higher ratio of Ru oxide to Ru (zero-valent) than the conventional nuclear hydrogenation reaction catalyst, the nuclear water of the aromatic compound is It is inferred that the activity for the addition reaction is improved.

In the catalyst for nuclear hydrogenation reaction of the present invention, the Ru oxide contained in the catalyst particles may be in a state in which a hydroxyl group is bonded to a part of the Ru oxide.

According to the present invention, there is provided a catalyst for nuclear hydrogenation reaction which has a catalytic activity superior to that of a conventional ruthenium catalyst in the nuclear hydrogenation reaction of an aromatic compound in which one or more amino groups are bonded to an aromatic ring.

It is a schematic diagram which shows schematic structure of the XPS apparatus for demonstrating the analysis conditions of the X ray photoelectron spectroscopy (XPS) in this invention.

<Catalyst for nuclear hydrogenation reaction>
Hereinafter, preferred embodiments of the catalyst for nuclear hydrogenation reaction of the present invention will be described in detail.
The catalyst for hydrogenation reaction of the present invention is used in a nuclear hydrogenation reaction for hydrogenating at least one of π-bonds of the aromatic ring in which an aromatic ring is bound to one or more amino groups. .

For example, the aromatic ring of the aromatic compound “4-tert-butylaniline [4-tert-Butylaniline, a reactant 1 in the following reaction formula (1)] represented by the following chemical reaction formula (1): The π bond can be hydrogenated and used in a nuclear hydrogenation reaction to convert to “4-tert-butylcyclohexylamine [(4-tert-Butylcyclohexylamine, product 2 in the following reaction formula (1))]”.

The catalyst for nuclear hydrogenation reaction of the present invention only needs to contain a support and catalyst particles supported on the support, and the form of the support of the catalyst particles is not particularly limited, and various structures can be adopted. obtain.

(Carrier)
The carrier is not particularly limited as long as it can carry catalyst particles and has a relatively large surface area, but it has good dispersibility in a solution containing catalyst particles and is inert preferable.

As the inert carrier, for example, carbon-based materials (carbon), silica, alumina, cilia carmina, magnesia and the like are preferable, and alumina is particularly preferable.
As for the alumina support with a pore size PS obtained by BJH method is 8.00nm ~ 12.00nm, a pore volume PV obtained by BJH method 0.250cm ³ /g~0.400cm ³ / g Is preferred.

Here, in the present invention, the pore size PS is determined from the desorption isotherm which is the relationship between the relative pressure and the adsorption amount when the adsorbate (gas molecule) is desorbed from the solid surface by the BJH (Barrett, Joyner, Hallender) method. Value (BJH Desorption average pore diameter). Further, in the present invention, the pore volume PV is also a value (BJH Desorption cumulative volume of pores between 1.7000 nm and 300.0000 nm diameter) determined by the BJH method.

Examples of the carbon-based material include glassy carbon (GC), fine carbon, carbon black, graphite, carbon fibers, activated carbon, pulverized products of activated carbon, carbon nanofibers, carbon nanotubes and the like.

In addition, as a carbon-type material, electroconductive carbon is preferable and electroconductive carbon black is preferable as electroconductive carbon especially. Moreover, as conductive carbon black, brand names "Ketjen black EC300J", "Ketjen black EC600", "Carbon EPC" etc. (made by Lion Chemical Co., Ltd.) can be illustrated.

(Catalyst particles)
Next, in the present invention, the catalyst particles supported on the above-mentioned support contain Ru (zero valent) and Ru oxide, and in the analysis region near the surface measured by X-ray photoelectron spectroscopy (XPS) The ratio R _Ru (atom%) of Ru (0 valence) and the ratio R _{RuO x} (atom%) of the Ru oxide satisfy the condition of the following formula (1).
0.60 ≦ {R _RuOx / (R _RuOx + R _Ru )} ≦ 0.90 Formula (1)

The amount of the catalyst particles supported on the carrier is not particularly limited as long as the effects of the present invention are not impaired, and the reaction system and reaction conditions in which the catalyst for nuclear hydrogenation reaction of the present invention is employed It is set appropriately. Usually, it may be about 0.5 to 10 wt%.

Here, the supported amount refers to the value (rate) obtained by the formula: {mass of catalyst particles / (mass of catalyst particles + mass of carrier)} × 100. Here, the mass of the catalyst particles refers to the mass of the Ru component obtained by combining Ru (zero-valent) and the Ru oxide contained in the catalyst particles.

In the catalyst for nuclear hydrogenation reaction of the present invention, the value of {R _{RuO x} / (R _{RuO x} + R _Ru )} shown in the above-mentioned formula (1) _should be configured to be 0.60 or more and 0.90 or less. Thus, in the nuclear hydrogenation reaction of an aromatic compound, catalytic activity superior to that of a conventional ruthenium catalyst can be exhibited.

When the value of this {R _{RuO x} / (R _{RuO x} + R _Ru )} is large, more Ru oxides are present in the vicinity of the surface of the catalyst particle for nuclear hydrogenation reaction than Ru (0 valence), and this {R _The small value of _{RuO x} / (R _{RuO x} + R _Ru )} means that less Ru oxide is present in the vicinity of the surface of the catalyst particle for nuclear hydrogenation reaction than Ru (zero valence).

And when more Ru oxides are present in the vicinity of the surface of the catalyst particle for nuclear hydrogenation reaction of the present invention than Ru (0 valence), the detailed mechanism has not been elucidated, but one or more amino groups in the aromatic ring The effect of improving the catalytic activity for the nuclear hydrogenation reaction of the aromatic compound having a group bonded thereto tends to be obtained.

Conversely, when less Ru oxide is present in the vicinity of the surface of the catalyst particle for nuclear hydrogenation reaction of the present invention than Ru (0 valence), an aromatic compound in which one or more amino groups are bonded to an aromatic ring The effect of reducing the catalytic activity for the nuclear hydrogenation reaction tends to be obtained.

In the present invention, by _setting the value of R _RuOx / (R _RuOx + R _Ru ) shown in the above-mentioned formula (1) to be 0.60 or more and 0.90 or less, these functions and effects are realized in a well-balanced manner. It is

In the present invention, the Ru oxide contained in the catalyst particles may be in a state in which a hydroxyl group is bonded to a part thereof.

In the present invention, X-ray photoelectron spectroscopy (XPS) is performed under the following analysis conditions (A1) to (A5).
(A1) X-ray source: monochromized AlKα
(A2) Photoelectron extraction accuracy: θ = 75 ° C.
(A3) Charge correction: correction with C1s peak energy set to 284.8 eV (A4) analysis region: 200 μm,
(A5) Chamber pressure during analysis: about 1 × 10 ^-6 Pa

Here, as shown in FIG. 1, the X-ray emitted from the X-ray source 32 is irradiated to the sample set on the sample stage 34, and the photoelectron extraction accuracy θ of (A2) is emitted from the sample This is the angle θ when the photoelectrons are received by the spectroscope 36. That is, the photoelectron take-off accuracy θ corresponds to the angle between the light receiving axis of the spectroscope 36 and the surface of the layer of the sample on the sample stage 34.

<Method of producing catalyst for nuclear hydrogenation reaction>
The method for producing a catalyst for nuclear hydrogenation reaction of the present invention is not particularly limited as long as the method can support the above-described catalyst particles on a carrier.

For example, an impregnation method in which a support is brought into contact with a solution containing a Ru compound, and the support is impregnated with a catalyst component, a liquid phase reduction method performed by adding a reducing agent to a solution containing a catalyst component, an electrochemical deposition method, chemistry A production method employing a reduction method, a reduction deposition method using adsorbed hydrogen, and the like can be exemplified.

However, the production conditions in the production of the catalyst for nuclear hydrogenation reaction are the ratio R _Ru (atom%) of Ru (0 valence) in the analysis region near the surface measured by X-ray photoelectron spectroscopy (XPS), It is necessary to adjust the synthesis reaction conditions in the manufacturing process so that the proportion of Ru oxide R _RuOx (atom%) satisfies the condition of the formula (1) described above.

In addition, as a method for producing the catalyst for nuclear hydrogenation reaction of the present invention so as to satisfy the essential condition shown in the above-mentioned formula (1), for example, a catalyst precursor obtained in each production step, and finally The chemical composition and structure of the obtained catalyst for nuclear hydrogenation reaction are analyzed using various known analysis methods, and the obtained analysis result is fed back to each manufacturing process to select the raw material to be selected, the compounding ratio of the raw material, Methods for preparing and changing the synthesis reaction, reaction conditions of the synthesis reaction (temperature, pressure of gas component, solvent) and the like can be mentioned.

More specifically, for example, in the catalyst for nuclear hydrogenation reaction of the present invention, a water-soluble Ru salt is dissolved in water to form Ru hydroxide, and the Ru hydroxide is used as a carrier (preferably alumina) The synthesis can be performed through a first step of synthesizing a supported catalyst precursor and a second step of heating and drying the catalyst precursor obtained in the first step in air.

Then, the type of Ru salt in the first step, the amount (concentration) of Ru salt to be added to water, the pH of the aqueous solution in which the Ru salt is dissolved, the temperature of the aqueous solution, the temperature of heating / drying treatment in the second step, and the treatment time By adjusting, the catalyst for nuclear hydrogenation reaction can be synthesized so as to satisfy the condition of the formula (1) described above.

Furthermore, a third step of reducing the catalyst for nuclear hydrogenation reaction obtained by obtaining the second step using a reducing agent as a precursor may be carried out, if necessary. By this, the ratio R _Ru (atom value) of Ru (zero valence) and the ratio R _{RuO x} (atom%) of Ru oxide are adjusted so as to more surely satisfy the condition of the equation (1) described above. can do. The kind of reducing agent, the concentration of the reducing agent, the temperature of the reduction treatment in the third step, and the treatment time can be adjusted. When the third step is carried out, gas phase reduction in which hydrogen gas (reducing agent) is diluted with nitrogen gas may be preferably employed.

Further, in the second step, the heating and drying treatment is performed twice or more successively, and the measurement by X-ray photoelectron spectroscopy (XPS) is carried out in between to determine the ratio R _Ru (atom%) of Ru (0 valence) ) And the proportion of Ru oxide R _RuOx (atom%) may be confirmed.

Furthermore, when the third step is carried out, the precursor obtained in the second step is measured by X-ray photoelectron spectroscopy (XPS), and the ratio R _Ru (atomic valence) of Ru (zero valence), Ru oxidation After _{confirming the} product ratio R _RuOx (atom%), the reduction conditions in the third step may be adjusted as appropriate. As a result, the catalyst for nuclear hydrogenation reaction that satisfies the condition of the formula (1) described above can be synthesized more reliably.

Hereinafter, the present invention will be more specifically described by way of examples, but the present invention is not limited to the following examples.

Example 1
Ru (0 valence) and nuclear water添反applications catalyst of the present invention that catalyst particles supported by alumina (Al 2 _{O 3)} loading of particles to 5% by weight is a carrier comprising a Ru oxide (hereinafter, " A trade name “NECC-RA1” (manufactured by NE CHEMCAT Co., Ltd.) was manufactured as “catalyst 1 for nuclear hydrogenation reaction”.
The {R _RuOx / (R _RuOx + R _Ru )} value of the catalyst for nuclear hydrogenation reaction is shown in Table 1.
The nuclear hydrogenation reaction catalyst 1 comprises a first step of synthesizing alumina and a water-soluble Ru salt in water to synthesize a catalyst precursor having a Ru hydroxide supported on a carrier (alumina); The catalyst precursor obtained in one step was synthesized through a second step of heating and drying treatment (treatment temperature: 80 ° C.) in air.

Example 2
The procedure of Example 1 is repeated except that the value of {R _RuOx / (R _RuOx + R _Ru )} in the catalyst particles is changed to that shown in Table 1 with respect to the catalyst for nuclear hydrogenation reaction of Example 1. As a catalyst for nuclear hydrogenation reaction of the present invention (hereinafter referred to as “catalyst 2 for nuclear hydrogenation reaction”) (trade name “NECC-RA2” (manufactured by NE CHEMCAT Co.)) was produced.
The nuclear hydrogenation reaction catalyst 2 was subjected to the first step and the second step under the same conditions as the nuclear hydrogenation reaction catalyst 1 of Example 1, and thereafter the nuclear hydrogenation was obtained by obtaining the second step. A third step was carried out to reduce the reaction catalyst as a precursor using a reducing agent. In the third step, reduction treatment was performed at 100 ° C. in a gas atmosphere of 90% nitrogen and 10% hydrogen.

Example 3
The procedure of Example 1 is repeated, except that the value of {R _RuOx / (R _RuOx + R _Ru )} in the catalyst particles is changed to that shown in Table 1 with respect to the catalyst for nuclear hydrogenation reaction of Example 1. A trade name "NECC-RA3" (manufactured by NE CHEMCAT Co., Ltd.) was manufactured as a catalyst for nuclear hydrogenation reaction of the present invention (hereinafter referred to as "catalyst 3 for nuclear hydrogenation reaction").
The nuclear hydrogenation reaction catalyst 3 was subjected to the first step and the second step under the same conditions as the nuclear hydrogenation reaction catalyst 1 of Example 1, and then the nuclear hydrogenation was obtained by obtaining the second step. A third step was carried out to reduce the reaction catalyst as a precursor using a reducing agent. In the third step, reduction treatment was performed at 150 ° C. in a gas atmosphere of 90% nitrogen and 10% hydrogen.

«Comparative Example 1»
Catalyst 1 for a comparative nuclear hydrogenation reaction of the present invention (commodity 1 of the present invention) in the same manner as in Example 1 except that the value of {R _{RuO x} / (R _{RuO x} + R _Ru )} in the catalyst particles was changed to that shown in Table 1. The name "NECC-5E, manufactured by NE CHEMCAT" was manufactured.

[Evaluation test]
Using the catalyst for nuclear hydrogenation reaction obtained in the above Examples 1 to 3 and Comparative Example 1, according to the following reaction formula (1), the aromatic compound “4-tert-butylaniline [4-tert- Butylaniline, the π bond of the aromatic ring of the reaction product 1 in the following reaction formula (1) is hydrogenated to give “4-tert-butylcyclohexylamine [(4-tert-Butylcyclohexylamine, in the following reaction formula (1) The nuclear hydrogenation reaction was carried out to convert the product 2].
The reaction was carried out under the following reaction conditions. Solvent: isopropyl alcohol, concentration of reactant 1: 1.6 mol%, hydrogen gas: 0.6 MPa, reaction temperature: 60 ° C., reaction time: 6 hours.

(1) Surface analysis of catalyst for nuclear hydrogenation reaction by X-ray photoelectron spectroscopy (XPS): Surface analysis by XPS of the catalyst for nuclear hydrogenation reaction of Examples 1 to 3 and Comparative Example 1 is carried out And the ratio R _Ru (atom%) of Ru (zero valence) and the ratio R _{RuO x} (atom%) of Ru oxide were measured, and the value of {R _{RuO x} / (R _{RuO x} + R _Ru )} was calculated. .
Specifically, “Quantera SXM” (manufactured by ULVAC-PHI, Inc.) was used as an XPS apparatus under the following analysis conditions.
(A1) X-ray source: monochromized AlKα
(A2) Photoelectric extraction accuracy: θ = 75 ° C. (see FIG. 1)
(A3) Charge correction: correction with C1s peak energy set to 284.8 eV (A4) analysis region: 200 μm
(A5) Chamber pressure during analysis: about 1 × 10 ^-6 Pa
(A6) Measurement depth (escape depth): about 5 nm or less The analysis results are shown in Table 1. The ratio R Ru (zero valence) R _Ru (atom%) to the ratio Ru oxide R _{RuO x} (atom%) were calculated so as to be 100% for these two components.

(2) Measurement of Ru loading (ICP analysis)
For the nuclear hydrogenation reaction catalysts of Examples 1 and 2 and Comparative Example 1, the loading (wt%) of the catalyst particles containing Ru (0 valence) and Ru oxide was measured by the following method. That is, the catalyst for nuclear hydrogenation reaction was immersed in aqua regia to dissolve the metal. Next, the insoluble component alumina was removed from aqua regia. Next, the aqua regia from which alumina was removed was subjected to ICP analysis.
In the catalysts for nuclear hydrogenation reaction of Examples 1 to 3 and Comparative Example 1, the supporting rate of Ru {the supporting rate of Ru derived from Ru component obtained by combining Ru (zero valence) and Ru oxide} is 5 wt% Met.

(3) Calculation of conversion, yield The conversion (%) of the reactant 1 by measuring the content of the reactant 1, product 2 in the mixed composition obtained after the reaction, and the content ratio, the product The yield of 2 was calculated and the results are shown in Table 1.

From the results shown in Table 1, the catalysts of Examples 1 to 3 according to the present invention according to the present invention, in which the value of {R _{RuO x} / (R _{RuO x} + R _Ru )} satisfies the condition of Formula (1) described above, are Comparative Example 1 It was revealed that the conversion of reactant 1 and the yield of product 2 were higher than those of the catalysts of the prior art (conventional ruthenium catalysts). That is, it is apparent that the catalyst for nuclear hydrogenation reaction of the present invention has a catalytic activity superior to that of the conventional ruthenium catalyst in the nuclear hydrogenation reaction of an aromatic compound in which one or more amino groups are bonded to an aromatic ring. became.

The catalyst for nuclear hydrogenation reaction of the present invention has excellent catalytic activity in the nuclear hydrogenation reaction of an aromatic compound in which one or more amino groups are bonded to an aromatic ring, and an excellent yield of product can be obtained. it can. Accordingly, the present invention is a catalyst for nuclear hydrogenation reaction that can be applied to the synthesis of polyamideimide resin and the like as a raw material of high-performance plastic products, and contributes to the development of various industries.

Claims (1)

A catalyst for nuclear hydrogenation reaction, which is used in a nuclear hydrogenation reaction for hydrogenating at least one of π-bonds of the aromatic ring in which an aromatic ring has one or more amino groups bonded to the aromatic ring,
A carrier, and catalyst particles supported on the carrier,
The catalyst particles contain Ru (0 valence) and Ru oxide,
The ratio of Ru (zero valence) R _Ru (atom%) and the ratio of Ru oxide R _{RuO x} (atom%) in the analysis region near the surface measured by X-ray photoelectron spectroscopy (XPS) The condition of equation (1) is satisfied,
Nuclear hydrogenation reaction catalyst.
0.60 ≦ {R _RuOx / (R _RuOx + R _Ru )} ≦ 0.90 Formula (1)

Images