JP5748351B2 - Hydrogenation catalyst for aromatic compounds and method for hydrogenating aromatic compounds using the catalyst - Google Patents

Description

  The present invention relates to an aromatic compound hydrogenation catalyst and a hydrogenation method using the catalyst. More specifically, the present invention relates to a hydrogenation catalyst for an aromatic compound containing nickel, molybdenum and ruthenium, and a hydrogenation method using the catalyst.

  The hydrogenation reaction of an aromatic compound is a reaction that actually proceeds in the desulfurization process of a kerosene fraction and a light oil fraction in petroleum refining. Moreover, it has been performed for a long time as a technique for producing chemical products and solvents.

Conventionally, as hydrogenation catalysts for aromatic compounds, noble metals such as Pt and Pd and transition metals such as Ni and Cu are used as active metal species, and these metal species are supported on various carriers such as alumina, silica, and zeolite. Catalysts are mainly used.
When performing a hydrogenation reaction using these catalysts, a fixed bed reactor or the like is mainly used. The reaction conditions are a hydrogen atmosphere, a reaction temperature of 100 to 400 ° C., and a reaction pressure of 0.1 to 4 MPa. (For example, see Patent Documents 1 and 2).

  On the other hand, desulfurization agents containing nickel, molybdenum and ruthenium have been reported as desulfurization agents that can efficiently remove sulfur in hydrocarbons in the absence of hydrogen (see Patent Documents 3 and 4).

JP 2005-218958 A Special table 2009-531426 gazette JP 2007-254728 A JP 2007-254275 A

  In order to carry out the hydrogenation reaction of aromatic compounds more efficiently and at a low cost, the catalyst activity is improved (productivity improvement, catalyst cost reduction, equipment size reduction, etc.), and the reaction conditions are reduced (lower temperature, lower pressure). Equipment cost and operating power reduction), and the use of inexpensive raw material hydrogen is demanded.

Among these, inexpensive raw material hydrogen includes, for example, by-product hydrogen discharged from a refinery hydrotreating apparatus and hydrogen in a coke oven exhaust gas from an ironworks. However, these gases are gases having a low total pressure per se and a low so-called hydrogen partial pressure including lower hydrocarbon gases other than hydrogen. In addition, it often contains sulfur compounds such as hydrogen sulfide, and is low-grade hydrogen. Generally, when the hydrogen partial pressure is low, the speed of the hydrogenation reaction decreases. In addition, sulfur compounds such as hydrogen sulfide poison the hydrogenation catalyst and cause activity deterioration.
In view of the above, there is a demand for a hydrogenation catalyst that has mild conditions of low temperature and low hydrogen partial pressure and that is highly active even in the presence of a sulfur compound.

  Under such circumstances, the present inventors have intensively studied, and as a result, a catalyst capable of efficiently hydrogenating an aromatic compound even under conditions where a low reaction temperature, a low hydrogen partial pressure, and hydrogen sulfide coexist. As a result, the present invention has been completed.

That is, the present invention relates to the following aromatic compound hydrogenation catalyst and aromatic compound hydrogenation method.
(1) Nickel is 50 to 95 mass% in terms of oxide (NiO), molybdenum is 0.5 to 25 mass% in terms of oxide (MoO ₃ ), and ruthenium is 0.1 to 0.1 in terms of oxide (RuO ₂ ). A hydrogenation catalyst for an aromatic compound, comprising 12% by mass and an inorganic oxide, having a crystallite diameter of NiO of 3 nm or less and a specific surface area of 150 to 600 m ² / g.
(2) Using the aromatic compound hydrogenation catalyst of (1) above, reaction temperature 50 to 400 ° C., hydrogen partial pressure 0.05 to 3 MPa, [hydrogen (mol)] / [raw material aromatic compound (mol)] A method for hydrogenating an aromatic compound, wherein the aromatic compound is hydrogenated under conditions of a ratio of 1 to 15 and a liquid space velocity of 0.01 to 10 h- ¹ .

  The aromatic compound hydrogenation catalyst of the present invention has a specific composition and physical properties, so that the hydrogen partial pressure is low and the impurities such as hydrogen sulfide are contained in the high purity hydrogen atmosphere. However, aromatic compounds such as benzene, toluene, and naphthalene can be efficiently hydrogenated at a low temperature.

<Composition of aromatic hydrogenation catalyst>
The aromatic compound hydrogenation catalyst of the present invention (hereinafter sometimes referred to as “the hydrogenation catalyst of the present invention”) is 50 to 95% by mass of nickel in terms of oxide (NiO), and molybdenum as an oxide (MoO). ₃ ) 0.5 to 25% by mass in terms of conversion, 0.1 to 12% by mass of ruthenium in terms of oxide (RuO ₂ ), and an inorganic oxide, the crystallite diameter of NiO being 3 nm or less, and The specific surface area is 150 to 600 m ² / g. The hydrogenation catalyst of the present invention contains nickel, molybdenum, and ruthenium in a specific composition ratio, and has a specific crystallite diameter and specific surface area, thereby containing impurities such as hydrogen sulfide. However, the aromatic compound can be efficiently hydrogenated under mild conditions.

  Content of nickel in the hydrogenation catalyst of this invention is 50-95 mass% in conversion of an oxide (NiO), Preferably it is 60-90 mass%, More preferably, it is 70-90 mass%. If the amount of nickel oxide is 50% by mass or more, a desired hydrogenation activity is exhibited, and if it is 95% by mass or less, the hydrogenation activity is not saturated, and the hydrogenation activity is reduced due to aggregation of Ni. Is preferred because

The content of molybdenum in the hydrogenation catalyst of the present invention, 0.5 to 25 wt% of an oxide (MoO ₃₎ in terms of, preferably 0.5 to 20 wt%, more preferably 1 to 10 mass%. If the amount of molybdenum oxide is 0.5% by mass or more, the desired hydrogenation activity is exhibited, which is preferable. If the amount is 25% by mass or less, the hydrogenation activity is not saturated and the reduction in hydrogenation activity is less likely to occur. Preferred

The ruthenium content in the hydrogenation catalyst of the present invention is 0.1 to 12% by mass, preferably 0.1 to 10% by mass in terms of oxide (RuO ₂ ). If the amount of ruthenium oxide is 0.1% by mass or more, a desired hydrogenation activity is exhibited, and if it is 12% by mass or less, the hydrogenation activity is not saturated and it is economically desirable.

  The hydrogenation catalyst of the present invention further contains an inorganic oxide in addition to the above nickel, molybdenum and ruthenium. When an inorganic oxide is used, the hydrogenation active metal is dispersed and attached to the oxide, so that the dispersibility is improved, the hydrogenation activity is improved, and the catalyst life is expected to be extended. Further, since the moldability and strength of the catalyst are also improved, it is desirable to use an inorganic oxide for obtaining a highly active and highly durable catalyst.

The kind of the inorganic oxide is not particularly limited, but an oxide of any one element selected from the group consisting of Si, Al, B, Mg, Ce, Zr, P, Ti, W, Mn, or a mixture thereof, Or the composite oxide of 2 or more types of elements is preferable. These inorganic oxides may have an amorphous or crystalline crystal structure. For _{example, SiO 2, Al 2 O 3} , TiO 2, B 2 O 3, MgO, SiO 2 -Al 2 O 3, Al 2 O 3 -B 2 O 3, SiO 2 -MgO, zeolite and the like.

Among various inorganic oxides, SiO ₂ , Al ₂ O ₃ , and SiO ₂ —Al ₂ O ₃ having a relatively high specific surface area and excellent in moldability, crushing strength, and abrasion properties are particularly preferable. This SiO ₂ —Al ₂ O ₃ can usually be produced in the course of firing a mixture containing both the Si raw material and the Al raw material in the catalyst firing step described later.

  The content of the inorganic oxide component is not particularly limited and may be appropriately selected under various conditions. Usually, it is preferably 0.5 to 49.4% by mass, more preferably 0.5 to 4% based on the entire catalyst. It may be in the range of 40% by mass, more preferably 0.5-30% by mass. When the content is 0.5% by mass or more, the effect as the inorganic oxide component is sufficiently exhibited, and when it is 49.4% by mass or less, the desulfurization performance is prevented from being lowered due to the reduction of the hydrogenation active component. Can be preferred.

  The crystallite diameter in the oxide (NiO) state of nickel, which is one of the components of the hydrogenation catalyst of the present invention, is 3 nm or less, preferably 2.6 nm or less, more preferably 2.4 nm or less. Generally, the smaller the crystallite size at the active site, the greater the surface area and the higher the activity. If the crystallite diameter of NiO is 3 nm or less, sufficient hydrogenation activity is exhibited, which is preferable.

Moreover, the specific surface area of the hydrogenation catalyst of this invention is 150-600 m < ² > / g in the state before a reduction process, and it is preferable that it is 180-500 m < ² > / g. A specific surface area of 150 m ² / g or more is preferable because the number of active sites for hydrogenation increases and sufficient hydrogenation activity is obtained. Moreover, if a specific surface area is 600 m < ² > / g or less, an average pore diameter becomes comparatively large and sufficient hydrogenation activity is obtained and it is preferable.

  The shape of the hydrogenation catalyst of the present invention is not particularly specified, and may be in any state such as a molded body (extruded cylinder, tablet cylinder, sphere, etc.), a granular body sieved with a mesh, or a powder. In view of the above, a granular body that is sieved with a molded body or a mesh is preferable. In order to make the shape of the catalyst into a granulated body or a granular body screened with a mesh, it is desirable to use an inorganic oxide. Further, the size of the catalyst is not particularly limited regardless of the size of the molded body or the granular material sieved with a mesh, but usually the diameter or length is 0.1 to 10 mm, more preferably 0.1 to 5 mm. Preferably

<Method for Producing Aromatic Compound Hydrogenation Catalyst>
The method for producing the catalyst is not particularly defined and can be appropriately prepared by any method. For example, using an inorganic oxide, it can be produced by an impregnation method, a kneading method, a coprecipitation method, a sol-gel method, an equilibrium adsorption method, etc. In order to effectively function nickel, molybdenum and ruthenium, A coprecipitation method is preferred.
For the addition of the nickel component, the coprecipitation method is more preferable than the impregnation method because the loading amount by one operation can be increased. For the addition of the ruthenium component, an impregnation method is more preferable because high activity is obtained.

  Although the suitable manufacturing method of the hydrogenation catalyst of this invention is demonstrated concretely below, the manufacturing method of the hydrogenation catalyst of this invention is not limited to this.

[Ni, Mo coprecipitation + Ru impregnation (1)]
A first method for producing a suitable catalyst will be described.
In this method, first, an acidic aqueous solution containing a nickel raw material and a basic aqueous solution containing a molybdenum raw material are separately prepared. The inorganic oxide raw material can be added to either an acidic aqueous solution or a basic aqueous solution. When using 2 or more types of inorganic oxide raw materials, you may add an inorganic oxide raw material to both aqueous solution.

For example, when producing a catalyst containing SiO ₂ and Al ₂ O ₃ as inorganic oxides, an acidic aqueous solution containing a nickel raw material and an aluminum raw material and a basic aqueous solution containing a molybdenum raw material, a Si raw material and an inorganic base are prepared. In the production of the catalyst containing only SiO ₂ as the inorganic oxide, for example, to prepare an acidic aqueous solution containing nickel material, molybdenum material, a basic aqueous solution containing a Si source and inorganic bases, respectively.

Although it does not specifically limit as a nickel raw material, Water-soluble nickel metal salts, such as nickel nitrate, nickel sulfate, nickel chloride, nickel acetate, and its hydrate can be used conveniently. Although it does not specifically limit as a molybdenum raw material, Water-soluble molybdenum metal salts, such as ammonium molybdate and molybdophosphoric acid, and its hydrate can be used conveniently. These nickel raw materials and molybdenum raw materials may be used alone or in combination of two or more.
Further, the aluminum raw material is not particularly limited, but boehmite, pseudoboehmite, γ alumina, β alumina and the like are preferable. These can be used in the form of powder or sol, and may be used alone or in combination of two or more.
The acidic aqueous solution containing the nickel raw material and the aluminum raw material is preferably prepared with an acid such as hydrochloric acid, sulfuric acid or nitric acid.

Furthermore, the Si raw material is not particularly limited, but silica, water glass, sodium metasilicate, diatomaceous earth, mesoporous silica (MCM41) and the like are preferable.
The inorganic base is preferably an alkali metal carbonate or hydroxide, such as sodium carbonate, sodium hydrogen carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, etc., with sodium carbonate being particularly preferred. .
The amount of the inorganic base used is advantageously selected so that the mixed solution of the acidic aqueous solution and the basic aqueous solution is substantially neutral to basic in the next step. Si raw material and inorganic base may be used independently and may be used in combination of 2 or more types.
The aluminum raw material and Si raw material are used for adding an inorganic oxide component to the catalyst. The same applies to the second and third methods described later.

  Next, each prepared aqueous solution is heated at 25-90 degreeC, respectively, and both are mixed. And it stirs about 0.5 to 3 hours, hold | maintaining liquid temperature at 25-90 degreeC, and completes reaction. The pH after mixing the acidic aqueous solution and the basic aqueous solution is preferably 6 or more, more preferably in the range of 6 to 11, and still more preferably in the range of 6.5 to 10. A pH of 6 or more is preferable because nickel and molybdenum precipitate efficiently. Moreover, it is preferable from the surface of manufacturing cost that the usage-amount of an inorganic base can be saved that pH is 11 or less.

  After the precipitate of the reacted aqueous solution is filtered and washed with water, the solid is dried at a temperature of about 50 to 150 ° C. by a known method. The dried product thus obtained is preferably fired at a temperature in the range of 200 to 450 ° C. for 1 to 5 hours.

  Then, the fired body obtained as described above is impregnated and supported with an aqueous solution in which a ruthenium raw material is dissolved in ion-exchanged water.

Although it does not specifically limit as a ruthenium raw material, Water-soluble ruthenium metal salts, such as ruthenium chloride and ruthenium nitrate, and its hydrate can be used conveniently.
Moreover, the alkaline aqueous solution used for immobilizing the ruthenium component is not particularly limited, but aqueous solutions of ammonia water, ammonium carbonate, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium hydrogen carbonate and the like can be used.

  The temperature at which the ruthenium component is impregnated and the immobilized product is dried is preferably 120 ° C. or lower. If it is 120 degrees C or less, the production | generation of ruthenium oxide can be suppressed and a subsequent reduction | restoration process can be made efficient. Further, the drying method is not particularly limited, and any of drying under normal pressure, drying under reduced pressure, drying in air, and drying under an inert gas atmosphere can be arbitrarily selected.

[Ni, Mo coprecipitation + Ru impregnation (2)]
Next, a second method for producing a suitable catalyst will be described. In this method, first, an acidic aqueous solution containing a nickel raw material and a molybdenum raw material and a basic aqueous solution containing an inorganic oxide raw material are separately prepared. When using 2 or more types of inorganic oxide raw materials, an inorganic oxide raw material can also be added to acidic aqueous solution.

For example, when producing a catalyst containing SiO ₂ and Al ₂ O ₃ as inorganic oxides, an acidic aqueous solution containing nickel raw material, molybdenum raw material and aluminum raw material, and a basic aqueous solution containing Si raw material and inorganic base are prepared. .

As the nickel raw material, the molybdenum raw material, the aluminum raw material, the Si raw material, and the inorganic base, those similar to the first method can be used. Moreover, it is preferable to prepare acidic aqueous solution containing nickel raw material, molybdenum raw material, and aluminum raw material with acids, such as hydrochloric acid, a sulfuric acid, and nitric acid. The pH after mixing the acidic aqueous solution and the basic aqueous solution is preferably in the same range as the pH described in the first method.
The prepared acidic aqueous solution and basic aqueous solution are mixed to complete the reaction under the same conditions as in the first method. The produced precipitate is filtered, washed with water, dried, and the dried product is fired.

  Further, the fired body thus obtained is impregnated and supported with an aqueous solution in which a ruthenium raw material is dissolved, and after drying, the ruthenium component is insoluble and fixed with an alkaline aqueous solution, followed by filtration, washing with water and drying. At this time, as the ruthenium raw material and the alkaline aqueous solution, those similar to the first method can be used. Next, the obtained impregnated and immobilized ruthenium component is dried in the same manner as in the first method.

[Ni coprecipitation + Mo, Ru impregnation (3)]
Next, the 3rd method of the manufacturing method of a suitable catalyst is demonstrated. In this method, first, an acidic aqueous solution containing a nickel raw material and a basic aqueous solution containing an inorganic oxide raw material are separately prepared. When using 2 or more types of inorganic oxide raw materials, an inorganic oxide raw material can also be added to acidic aqueous solution.

For example, when producing a catalyst containing SiO ₂ and Al ₂ O ₃ as inorganic oxides, an acidic aqueous solution containing a nickel raw material and an aluminum raw material and a basic aqueous solution containing a Si raw material and an inorganic base are prepared.

As the nickel raw material, the aluminum raw material, the Si raw material, and the inorganic base, those similar to the first method can be used. Moreover, it is preferable to prepare acidic aqueous solution containing a nickel raw material and an aluminum raw material with acids, such as hydrochloric acid, a sulfuric acid, and nitric acid. The pH after mixing the acidic aqueous solution and the basic aqueous solution is preferably in the same range as the pH described in the first method.
The prepared acidic aqueous solution and basic aqueous solution are mixed to complete the reaction under the same conditions as in the first method. The produced precipitate is filtered, washed with water, dried, and the dried product is fired.

The obtained fired product is impregnated with an aqueous solution obtained by dissolving a molybdenum raw material in ion-exchanged water. If the molybdenum raw material is not dissolved in ion-exchanged water, a small amount of ammonia water may be added.
At this time, as the molybdenum raw material, the same material as in the first method can be used.
The obtained impregnated product of molybdenum raw material aqueous solution is dried at a temperature of about 50 to 150 ° C. by a known method, and the dried product is preferably fired at a temperature in the range of 200 to 450 ° C. for 1 to 5 hours.

  Further, the fired body thus obtained is impregnated and supported with an aqueous solution in which a ruthenium raw material is dissolved, and after drying, the ruthenium component is insoluble and fixed with an alkaline aqueous solution, followed by filtration, washing with water and drying. At this time, as the ruthenium raw material and the alkaline aqueous solution, those similar to the first method can be used. Next, the obtained impregnated and immobilized ruthenium component is dried in the same manner as in the first method.

<Method of hydrogenating aromatic compounds>
The hydrogenation catalyst of the present invention produced as described above is preferably subjected to a reduction treatment before being subjected to a hydrogenation reaction. Thereby, the metal contained in the catalyst is activated and the aromatic compound is easily hydrogenated.

  As the reduction method, a known method such as gas phase reduction using hydrogen, CO, etc., liquid phase reduction using formaldehyde, ethanol, or the like can be used, but hydrogen reduction by gas phase is preferable, and in this case, hydrogen reduction It is preferable to carry out at 200-500 degreeC by atmosphere, and it is more preferable to carry out at the temperature of 300-450 degreeC.

  The hydroreduction treatment may be performed in the reactor (on-site) of the hydrogenation reaction of the aromatic compound, or may be performed in a prior hydroreduction treatment apparatus (off-site). Since the reduction treatment temperature is higher than the reaction temperature, off-site reduction is preferable in consideration of the fact that the design temperature of the reactor used is increased. Further, in the off-site hydroreduction treatment, when the catalyst is taken out into the air after the reduction treatment, heat is generated due to rapid oxidation of the reduced Ni metal or Ru metal, Ni, Ru, and other components are aggregated, and the surface area There is a risk of decline. Therefore, it is more preferable to passivate the metal surface using a trace amount of oxygen, carbon dioxide, or the like after the reduction treatment and before extraction into the air. In the above passivation treatment, even when a part of the surface layer of metal Ni is oxidized to Ni oxide (NiO) and extracted into the air, further Ni oxidation does not proceed and it can be handled stably. . The particle diameter of NiO produced at this time may vary somewhat depending on the conditions of the passivation treatment, but the particle diameter of NiO defined in the present invention is the same as that before the reduction and passivation treatment. It means the state.

In the hydrogenation reaction of an aromatic compound using the hydrogenation catalyst of the present invention, the hydrogenation is usually carried out by filling the catalyst into a reactor and bringing the starting aromatic compound into contact with the catalyst under hydrogen supply.
As a method for bringing the aromatic compound and the catalyst into contact, generally, a catalyst layer is formed in a fixed bed reactor, and the raw material aromatic compound and hydrogen can be supplied.

  As conditions for the hydrogenation reaction, the hydrogen partial pressure is 0.05 to 3 MPa, preferably 0.1 to 1 MPa. In general, the higher the hydrogen partial pressure, the more advantageous for the hydrogenation reaction. However, in the present invention, the hydrogenation reaction can be efficiently carried out even at a low hydrogen partial pressure, so that low-grade hydrogen can be used effectively. In addition, it is not necessary to increase the total pressure with the booster to increase the hydrogen partial pressure, thereby reducing investment in facilities and operating power.

  The molar ratio of hydrogen to the raw material aromatic compound ([hydrogen (mol)] / [raw material aromatic compound (mol)] ratio) is 1 to 15, preferably 3 to 7. Generally, the larger the amount of hydrogen relative to the raw material, the more advantageous for the hydrogenation reaction. However, maintaining this range allows the hydrogenation reaction to proceed efficiently.

Needless to say, the purity of hydrogen used does not include impurities and high-purity hydrogen can be used. However, in the present invention, the hydrogen purity is low, and impurities such as sulfur compounds such as hydrogen sulfide are used to some extent. Even if it is contained, hydrogenation can proceed efficiently.
Regarding hydrogen purity, although depending on the total pressure of the gas used, for example, about 20 vol% or more, it can be suitably used. Further, hydrogen sulfide does not cause rapid deactivation of hydrogenation activity even if it is present with hydrogen as long as it is up to about 100 (volume) ppm.

Moreover, reaction temperature is 50-400 degreeC, Preferably it is 70-300 degreeC, More preferably, it is 70-200 degreeC, More preferably, it is 80-200 degreeC, More preferably, it is 80-150 degreeC. The present invention is characterized in that hydrogenation proceeds even at a low temperature. However, at a temperature of 50 ° C. or lower, the reaction rate decreases, and conversely, when the temperature is too high, the nickel component in the catalyst aggregates and becomes active sites. The number may decrease and the hydrogenation performance may be reduced.
Liquid hourly space velocity (LHSV) 0.01~10h ^-1, preferably 0.1~3h ^-1.

  The aromatic compounds used as raw materials include so-called benzene nuclei such as monocyclic aromatic compounds such as benzene, toluene, xylene, phenols, thiophenols and anilines, and polycyclic aromatic compounds such as naphthalene, anthracene and phenanthrene. Hydrocarbons and heterocyclic aromatic compounds such as thiophene, pyridine, furan, etc., but are not particularly limited as long as they are hydrocarbons. For example, kerosene or light oil is used as a raw material in each fraction. It is also possible to hydrogenate the aromatic compound.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
First, the physical properties of the catalysts and the instrumental analysis methods for toluene conversion in Examples and Comparative Examples are shown below.

<Measurement of specific surface area of catalyst>
A BET surface area measuring device (Belsorb Mini) was used for measurement of BET (Braunauer-Emmett-Tailor specific surface area) specific surface area. About 200 to 300 mg of the sample is precisely weighed, filled in a quartz sample tube, heated from room temperature to 400 ° C. over 1 hour while reducing the pressure to 10 ⁻¹ to 10 ⁻³ mmHg level, The deaeration treatment was performed by maintaining at the same temperature for 3 hours. Thereafter, the temperature was lowered to room temperature while reducing the pressure, the gas was replaced with high purity helium gas, and the weight of the sample after deaeration was precisely weighed. Thereafter, nitrogen adsorption was performed at the liquefied nitrogen temperature, and the specific surface area was measured.

<X-ray diffraction analysis method of catalyst>
An X-ray diffractometer (RINT-2500V) manufactured by Rigaku Corporation was used. The sample to be measured is pulverized and packed in a sample plate. X-ray diffraction (scanning range 5 to 90 °, sample rotation speed 20 rpm, divergence slit 1 °, scattering slit 1 °, light receiving slit 1 °, scan speed 2 ° / min) (Source Cu—Kα ray) measurement was performed.
The crystallite diameter of NiO was calculated by the Scherrer equation by detecting a diffraction peak having a peak top in the vicinity of 2θ = 62 ° by X-ray diffraction measurement.

<Hydrogenation reaction of toluene>
A reaction tube with an inner diameter of 15 mm is filled with 10 mL of catalyst, reaction temperature 50 to 350 ° C., LHSV = 1.0 h ⁻¹ , hydrogen / toluene = 5 mol / mol, total pressure 0.6 MPa, hydrogen partial pressure 0.12 MPa, H _2. The reaction was performed under the condition of S = 0 to 50 ppm. Moreover, the FID-GC analysis of the product oil was performed, and the conversion rate of toluene was calculated | required by the following formula from the area value. In addition, only methylcyclohexane was confirmed as a toluene hydrogenation product, and other compounds were not detected.

Formula: Toluene conversion rate (%) = [Area value of methylcyclohexane] / ([Area value of toluene] + [Area value of methylcyclohexane]) × 100

[Example 1; Ni, Mo coprecipitation + Ru impregnation (1) (first method)]
Boehmite AP-3 (manufactured by Catalysts & Chemicals Industries) 1.24 g, a 1N-HNO ₃ solution 40mL was added to ion-exchanged water 1L, after warming to 80 ° C., was added 149g of _{Ni (NO 3) 2 · 6H} 2 O Preparation Liquid A was obtained. Separately prepared ion-exchanged water 1L colloidal silica Snowtex XS (produced by Nissan Chemical) 33.9 g, sodium carbonate _{99.4g, (NH 4) 6 Mo} 7 O 24 · 5H 2 O was added 3.0 g, in 80 ° C. It heated and the preparation liquid B was obtained. While maintaining the prepared solutions A and B at 80 ° C., the solution B was instantaneously added to the solution A and stirred for 1 hour. Thereafter, it was washed with 5 L of ion-exchanged water, and after filtration, dried in air at 120 ° C. for 12 hours, calcined at 400 ° C. for 1 hour, and the obtained calcined product was crushed, 1.0 mm and 1.4 mm The sieve was screened with a sieve having the following mesh. Next, 30 g of the above-mentioned mesh crushed in an aqueous solution in which 2.3 g of RuCl ₃ .nH ₂ O (manufactured by Kojima Chemical Co., Ru content: 41 mass%, n = 1 to 3) is dissolved in 11.4 g of ion-exchanged water. 1 hour, impregnating and supporting the aqueous solution on the mesh crushed, dried, soaked in 150 g of 7N-NH ₃ water for 1 hour, washed with 2 L of ion-exchanged water, filtered, dried at 120 ° C., catalyst 1 was obtained.

[Example 2; Ni, Mo coprecipitation + Ru impregnation (1) (first method)]
40 mL of 1N-HNO ₃ aqueous solution was added to 1 L of ion exchange water, heated to 80 ° C., and then 164 g of Ni (NO ₃ ) ₂ .6H ₂ O was added to obtain Preparation A. Colloidal silica SNOWTEX XS in deionized water 1L separately prepared (manufactured by Nissan Chemical Industries, Ltd.) 26.7 g, sodium carbonate 99.4 _g, a _{6 Mo 7 O 24 · 5H 2} O (NH 4) 1. 2g was added and it heated at 80 degreeC and the preparation liquid B was obtained. While maintaining the prepared solutions A and B at 80 ° C., the solution B was instantaneously added to the solution A and stirred for 1 hour. Thereafter, it was washed with 5 L of ion-exchanged water, and after filtration, dried in air at 120 ° C. for 12 hours, calcined at 400 ° C. for 1 hour, and the obtained calcined product was crushed, 1.0 mm and 1.4 mm The sieve was screened with a sieve having the following mesh. Next, 30 g of the above-mentioned mesh crushed in an aqueous solution in which 0.6 g of RuCl ₃ .nH ₂ O (manufactured by Kojima Chemical Co., Ru content: 41 mass%, n = 1 to 3) is dissolved in 11.4 g of ion-exchanged water. 1 hour, impregnating and supporting the aqueous solution on the mesh crushed, dried, soaked in 150 g of 7N-NH ₃ water for 1 hour, washed with 2 L of ion-exchanged water, filtered, dried at 120 ° C., catalyst 2 was obtained.

[Example 3; Ni coprecipitation + Mo, Ru impregnation (third method)]
Boehmite AP-3 (manufactured by Catalysts & Chemicals Industries) 1.24 g was added to deionized water 1L, after warming to 80 ° C., to obtain a _{Ni (NO 3) 2 · 6H} 2 O and 149g added preparation A. Colloidal silica snowtex XS (Nissan Chemical Co., Ltd.) 33.9 g and sodium carbonate 79.5 g were added to 1 L of ion-exchanged water separately prepared, and heated to 80 ° C. to obtain Preparation B. While maintaining the preparations A and B at 80 ° C., the solution B was added to the solution A over 10 minutes and stirred for 1 hour. At that time, the pH at 80 ° C. was 7.9. Thereafter, it was washed with 5 L of ion-exchanged water, and after filtration, dried in air at 120 ° C. for 12 hours, calcined at 400 ° C. for 1 hour, and the resulting molded product was crushed, 1.0 mm and 1.4 mm The resulting product was sieved with a sieve having a mesh of to obtain a molded product. To 20g of _{them, (NH 4) 6 Mo 7} O 24 · 5H 2 O1.3g the water and 7NNH ₃ water 9: 1 of an aqueous solution dissolved in mixed aqueous 8g ratio impregnated in air 120 ° C. And dried at 400 ° C. for 1 hour. Thereafter, 20 g of the fired product was immersed in an aqueous solution in which 1.5 g of RuCl3 · nH2O (manufactured by Kojima Chemical Co., Ru content 41 mass%, n = 1 to 3) was dissolved in 7.6 g of ion-exchanged water for 1 hour. The aqueous solution was impregnated and supported on the mesh crushed, dried, soaked in 100 g of 7N-NH ₃ water for 1 hour, washed with 2 L of ion-exchanged water, filtered, and dried at 120 ° C. to obtain Catalyst 3.

[Reference Example 1: Ni and Mo coprecipitation]
Boehmite AP-3 (Shokubai Kasei Kogyo) 1.24 g, was added a 1N-HNO ₃ solution 40mL ion-exchanged water 1L, after warming to _{80 ℃, Ni (NO 3)} 2 · 6H 2 O and 149g added preparation A was obtained. Separately prepared ion-exchanged water 1L colloidal silica Snowtex XS (produced by Nissan Chemical) 33.9 g, sodium carbonate _{99.4g, (NH 4) 6 Mo} 7 O 24 · 5H 2 O was added 3.0 g, in 80 ° C. It heated and the preparation liquid B was obtained. While maintaining the prepared solutions A and B at 80 ° C., the solution B was instantaneously added to the solution A and stirred for 1 hour. Thereafter, it was washed with 5 L of ion-exchanged water, and after filtration, dried in air at 120 ° C. for 12 hours, calcined at 400 ° C. for 1 hour, and the obtained calcined product was crushed, 1.0 mm and 1.4 mm The catalyst 4 was obtained by sieving with a sieve having a mesh of.

[Comparative Example 1; Pt—Pd / SiO ₂ —Al ₂ O ₃ ]
37.7 g of silica-alumina (silica / alumina mass ratio = 20/80, columnar molded product having a diameter of 1/16 inch) was added thereto, and 31.26 g of 10% hydrochloric acid aqueous solution was added to 31.26 g of chloroplatinic acid hexahydrate. A solution in which 5005 g and palladium chloride 0.6278 g were dissolved was added using a pipette. After being immersed at about 25 ° C. for 2 hours, it was air-dried, and the temperature of the immersion mixture was raised to 120 ° C. in a muffle furnace and dried for about 1 hour. Subsequently, it baked at 500 degreeC for 4 hours, and the catalyst 5 was obtained.

  Table 1 shows the compositions, physical properties, and results of the toluene hydrogenation reaction performed in Examples 1 to 3, Reference Example 1 and Comparative Example 1. From the results in Table 1, the hydrogenation catalyst of the present invention can catalyze the hydrogenation reaction at a lower temperature than the Pt—Pd noble metal catalyst at a hydrogen partial pressure as low as about 0.12 MPa, and It was found that toluene hydrogenation activity was high.

[Comparative Example 2; Ni / ZnO]
Dissolve 94.5 g of zinc acetate and 77.8 g of nickel nitrate in 1200 mL of water to prepare a mixed solution. To this solution, an aqueous solution of ammonium carbonate in which 22 g of ammonium carbonate was dissolved in 200 mL of water and 15% aqueous ammonia. In addition, a precipitate of zinc carbonate and basic nickel carbonate was obtained and left for about 12 hours. The precipitate was filtered, washed with water, dried at 120 ° C. for 12 hours, and calcined at 200 ° C. for 1 hour, 300 ° C. for 2 hours, 400 ° C. for 1 hour, and 510 ° C. for 16 hours to obtain Catalyst 6. The catalyst 6 had a NiO content of 29%, a specific surface area of 9 m ² / g, and a NiO crystallite diameter of 5.5 nm.

Hydrogenation reaction of toluene was conducted in the presence of hydrogen sulfide using the catalyst 1 of Example 1, the catalyst 5 of Comparative Example 1, and the catalyst 6 of Comparative Example 2, and the influence on the activity was examined. The results are shown in Table 2. The catalyst 1 maintained a high hydrogenation activity for a very long time of 1428 hours under the condition where H ₂ S coexists. In contrast, catalyst 5 was deactivated at a reaction time of 59 hours, and catalyst 6 had a toluene conversion of only 7% at a reaction time of 147 hours. That is, from the results of Table 2, it was found that the hydrogenation catalyst of the present invention was extremely excellent in H ₂ S resistance compared to Pt—Pd noble metal catalysts. The catalyst 4 containing no ruthenium maintains a high hydrogenation activity for a long time of 876 hours, and is much more resistant than the Pt—Pd noble metal catalyst as in the hydrogenation catalyst of the present invention. It was found to be excellent in H ₂ S.

Claims (2)

Nickel is 50 to 95% by mass in terms of oxide (NiO), molybdenum is 0.5 to 25% by mass in terms of oxide (MoO ₃ ), and ruthenium is 0.1 to 12% by mass in terms of oxide (RuO ₂ ). A hydrogenation catalyst for an aromatic compound, comprising an inorganic oxide, a crystallite diameter of NiO of 3 nm or less, and a specific surface area of 150 to 600 m ² / g. A reaction temperature of 50 to 400 ° C., a hydrogen partial pressure of 0.05 to 3 MPa, a [hydrogen (mol)] / [raw material aromatic compound (mol)] ratio of 1 using the aromatic compound hydrogenation catalyst according to claim 1. A method for hydrogenating an aromatic compound, wherein the aromatic compound is hydrogenated under a condition of ˜15 and a liquid space velocity of 0.01 to 10 h ⁻¹ .