Catalyst for hydrogenating aromatic compound

Abstract

The present invention addresses the problem of providing a catalyst having high activity in a reaction for hydrogenating an aromatic compound. This problem is solved by a catalyst for hydrogenating an aromatic compound, wherein: the Ni content is in the range of 40-90 mass% in terms of NiO with respect to the total mass of the catalyst; the Si content is in the range of 5-30 mass% in terms of SiO2 with respect to the total mass of the catalyst; the Mg content is in the range of 0.5-20 mass% in terms of MgO with respect to the total mass of the catalyst; the volume (PV1-10) of pores having a diameter in the range of 1-10 nm is 0.2 mL / g or more in a pore distribution obtained by using a nitrogen adsorption method; and the volume PV1-10 accounts for 60% or more of the volume (PV1-60) of pores having a diameter in the range of 1-60 nm.

Description

Catalyst for hydrogenating aromatic compounds

[0001] The present invention relates to a catalyst for hydrogenating aromatic compounds.

[0002] Aromatic compounds are cyclic unsaturated organic compounds, including compounds such as benzene, toluene, and xylene. Aromatic compounds are widely used as raw materials for various chemical products. One method for processing aromatic compounds is the hydrogenation reaction, which uses H2 to convert unsaturated bonds into saturated bonds. A catalyst is used in this hydrogenation reaction to promote the reaction.

[0003] For example, Patent Document 1 describes a ceramic ceramic material containing 50 to 95 mass % of nickel in terms of oxide (NiO), 0.5 to 25 mass % of molybdenum in terms of oxide (MoO), and an inorganic oxide, in which the crystallite diameter of NiO is 3 nm or less and the specific surface area is 150 to 600 m 2 / g。 Also, Patent Document 2 discloses a catalyst composition containing nickel, alumina, zirconia and diatomaceous earth for hydrogenating nitriles, aromatic hydrocarbons and nitro compounds.

[0004] However, in recent years, with the increase in demand for aromatic compounds, there has been a demand for catalysts with even higher activity for hydrogenating these compounds.

[0005] Japanese Patent Publication No. 6-34920 Japanese Patent Application Laid-Open No. 2013-202436

[0006] An object of the present invention is to provide a catalyst having high activity in the reaction of hydrogenating aromatic compounds.

[0007] The present inventors focused on the composition and pore structure of the catalyst and discovered that the above-mentioned problems can be solved by increasing the volume of pores containing Ni, Si, and Mg and having diameters in the range of 1 nm to 10 nm, and thus completed the present invention.

[0008] Specifically, the Ni content is in the range of 40% by mass to 90% by mass in terms of NiO relative to the total mass of the catalyst, the Si content is in the range of 5% by mass to 30% by mass in terms of SiO2 relative to the total mass of the catalyst, and the Mg content is in the range of 0.5% by mass to 20% by mass in terms of MgO relative to the total mass of the catalyst, and in the pore distribution obtained by the nitrogen adsorption method, the volume (PV) of pores having a diameter in the range of 1 nm to 10 nm is 1-10 ) is 0.2 mL / g or more and the pore volume (PV 1-60 ) The proportion of the aforementioned PV 1-10 It was found that when a catalyst with a ratio of 60% or more is used in the hydrogenation reaction of aromatic compounds, the activity is high.

[0009] According to the present invention, it is possible to provide a catalyst having high activity in the reaction of hydrogenating an aromatic compound.

[0010] 1 shows the pore size distribution of Example 1 and Comparative Example 1. PV 1-60 PV as a percentage of 1-10 This figure shows the relationship between the ratio of Ni and the aromatic compound hydrogenation rate. 3+ FIG. 1 is a graph showing the relationship between the concentration and the aromatic compound hydrogenation rate.

[0011] The present invention includes an invention related to a catalyst for hydrogenating aromatic compounds (hereinafter also referred to as the "catalyst of the present invention"). The catalyst of the present invention will be described in detail below. In the present invention, when a numerical range is indicated by "to", the numerical range includes both the upper and lower limits.

[0012] [Catalyst of the Present Invention] The catalyst of the present invention has a Ni content, calculated as NiO, in the range of 40% by mass to 90% by mass relative to the total mass of the catalyst. The catalyst of the present invention contains Ni in the form of either metallic Ni or Ni oxide. Metallic Ni functions as an active component in the reaction of hydrogenating aromatic compounds. Ni oxide functions as an active component when it is reduced (pretreated) to metallic Ni with hydrogen or the like before use in the reaction of hydrogenating aromatic compounds. The catalyst of the present invention has a Ni content, calculated as NiO, in the range of preferably 55% by mass to 90% by mass, more preferably 70% by mass to 90% by mass, relative to the total mass of the catalyst.

[0013] The catalyst of the present invention has a Si content in the range of 5% to 30% by mass, calculated as SiO2, relative to the total mass of the catalyst. The catalyst of the present invention contains Si as silica. Silica is included as a catalyst support or binder, and serves to highly disperse the Ni and increase the physical strength of the catalyst. Furthermore, although the reason for this is unclear, the activity is higher than when general alumina is used as a support. The catalyst of the present invention has a Si content in the range of 5% to 25% by mass, and more preferably 10% to 20% by mass, calculated as SiO2, relative to the total mass of the catalyst.

[0014] The catalyst of the present invention has a magnesium content, calculated as MgO, in the range of 0.5% by mass to 20% by mass relative to the total mass of the catalyst. The catalyst of the present invention is considered to contain magnesium as metallic magnesium or magnesium oxide. Mg is included in this catalyst as a promoter and serves to improve hydrogenation activity. The catalyst of the present invention has a magnesium content, calculated as MgO, in the range of preferably 2% by mass to 18% by mass, more preferably 3% by mass to 15% by mass, relative to the total mass of the catalyst.

[0015] The catalyst of the present invention has a pore volume (PV) of pores with diameters in the range of 1 nm to 10 nm in the pore distribution obtained by nitrogen adsorption method. 1-10 ) is 0.2 mL / g or more and the pore volume (PV 1-60 ) PV 1-10The catalyst of the present invention has developed small pores (diameter 1 nm to 10 nm), and it is believed that these pores provide a favorable reaction field for hydrogenating aromatic compounds. 1-10 However, the concentration may be in the range of 0.2 mL / g to 1.0 mL / g, or in the range of 0.2 mL / g to 0.5 mL / g. In addition, the catalyst of the present invention preferably has the above-mentioned ratio of 65% or more, and particularly preferably 70% or more. The upper limit of the above-mentioned ratio is 100%, and may be 95% or 90%.

[0016] The catalyst of the present invention has a surface Ni content measured by X-ray photoelectron spectroscopy (XPS). 3+ The concentration is preferably 60% or less, more preferably 55% or less. 3+ Reducing the amount of Ni on the catalyst surface tends to increase activity in the reaction of hydrogenating aromatic compounds. 3+ The lower limit of the concentration may be any of 5% or more, 10% or more, and 20% or more.

[0017] The catalyst of the present invention has a specific surface area of ​​100 m 2 / g~300m 2 / g, and preferably in the range of 125m 2 / g~275m 2 / g, more preferably in the range of 150m 2 / g~250m 2 / g. The specific surface area of ​​the catalyst of the present invention is calculated by the BET single-point method using a nitrogen adsorption method. The catalyst of the present invention having a specific surface area in the above-mentioned range is likely to have high activity in reactions for hydrogenating various compounds, not limited to aromatic compounds.

[0018] The catalyst of the present invention preferably has a Ni crystallite size in the range of 2 nm to 8 nm, more preferably in the range of 3 to 7 nm, and particularly preferably in the range of 4 nm to 6 nm. The Ni crystallite size of the catalyst of the present invention is an index representing the size of metallic Ni crystallites and can be calculated from the diffraction pattern obtained by X-ray diffraction measurement. The catalyst of the present invention having a Ni crystallite size in the above-mentioned range is likely to have high activity in reactions for hydrogenating various compounds, not limited to aromatic compounds.

[0019] The catalyst of the present invention preferably has a hydrogen adsorption capacity in the range of 200 μmol / g to 600 μmol / g, more preferably in the range of 250 μmol / g to 550 μmol / g, and particularly preferably in the range of 300 μmol / g to 500 μmol / g. This hydrogen adsorption capacity is an index representing the surface area of ​​metallic Ni. The catalyst of the present invention having a hydrogen adsorption capacity in the above-mentioned range is likely to have high activity in the hydrogenation reaction of aromatic compounds.

[0020] The catalyst of the present invention may contain optional components in addition to Ni, Si, and Mg. For example, it may contain a binder component. The binder component may include conventionally known components such as silica, alumina, and clay minerals. The catalyst of the present invention containing a binder component tends to have high physical strength, which is preferable from the viewpoint of lifespan and ease of handling when used as an industrial catalyst. The total content of the optional components is preferably 10% by mass or less, more preferably 7% by mass or less, and particularly preferably 5% by mass or less, based on the total mass of the catalyst.

[0021] The catalyst of the present invention may be in the form of a molded body or a powder. For example, when used in a gas-phase hydrogenation reaction, a molded body is preferred. Because gas-phase reactions have high contact efficiency between aromatic compounds and the catalyst, aromatic compounds can be hydrogenated in a fixed bed using a molded catalyst, thereby eliminating unit operations such as filtration and increasing productivity. In such cases, a spherical, cylindrical, or similar shape is preferred. This cylindrical shape also includes cylindrical, trilobal, and quadruple-leaf shapes. The size of the molded body is preferably in the range of 0.5 mm or more and 5 mm or less in major axis. Furthermore, when used in a liquid-phase hydrogenation reaction, a powdered form is preferred. Because liquid-phase reactions have poor contact efficiency between aromatic compounds and the catalyst, reactivity can be enhanced by using a powdered catalyst and carrying out the reaction in a suspension bed. In such cases, the catalyst of the present invention is preferably in the form of a powder with a median diameter of 5 μm to 100 μm. If the reactivity is sufficient even in the liquid phase, the reaction can also be carried out in a fixed bed.

[0022] The catalyst of the present invention exhibits high activity in the hydrogenation reaction of aromatic compounds, and also exhibits high activity with aromatic hydrocarbon resins, which are difficult to hydrogenate among aromatic compounds. Among aromatic hydrocarbon resins, the catalyst exhibits high activity with aromatic hydrocarbon resins having a number average molecular weight (Mn) of 100 or more and 30,000 or less, high activity with aromatic hydrocarbon resins having a number average molecular weight (Mn) of 100 or more and 20,000 or less, and particularly high activity with aromatic hydrocarbon resins having a number average molecular weight (Mn) of 100 or more and 10,000 or less.

[0023] [Method for producing adsorbent of the present invention] The catalyst of the present invention can be prepared, for example, by a production method comprising the following steps (1) and (2): (1) a catalyst precursor preparation step of preparing a catalyst precursor containing Ni, Mg, and Si; (2) a catalysis step of calcining and reducing the catalyst precursor to prepare a catalyst. Hereinafter, the method for producing the catalyst of the present invention will be described in detail, taking this production method as an example, but the method for producing the catalyst of the present invention is not limited to this production method.

[0024] In the catalyst precursor preparation step, a catalyst precursor containing Ni, Mg, and Si is prepared. The catalyst precursor containing Ni, Mg, and Si can be prepared by mixing an acidic aqueous solution containing Ni and Mg, an aqueous solution in which Si is dissolved or a dispersion of SiO2 in water, and a basic aqueous solution. Using this method, PV 1-10 In this step, it is preferable to prepare a catalyst precursor containing Ni and Si by mixing an acidic aqueous solution in which Ni is dissolved, an aqueous solution in which Si is dissolved or a dispersion of SiO2 in water, and a basic aqueous solution, and then add a water-soluble Mg salt to prepare a catalyst precursor containing Ni, Mg, and Si. Using this method, PV 1-10 The surface of the final catalyst tends to become larger. 3+ The reason for this is not clear, but by having a large amount of Mg on the surface of the catalyst precursor containing Ni and Si, the Ni 3+ In addition, when a water-soluble Mg salt was added to a precursor containing Ni and Al, the Ni concentration decreased. 3+ Since the concentration did not decrease, it is thought that the combination of Ni, Si, and Mg is also important.

[0025] In this process, a nickel salt with high solubility in water, such as nickel sulfate or nickel nitrate, is dissolved in water, and the pH is adjusted to an acidic level with an acid as needed to prepare an acidic aqueous solution containing dissolved Ni. The amount of Ni contained in this aqueous solution is adjusted to 40% to 90% by mass, calculated as NiO, based on the total mass of the final catalyst, taking into account the amounts of other components added.

[0026] In this process, sodium silicate and water can be mixed to prepare an aqueous solution containing dissolved silicon. Alternatively, silica or a silica-based mineral such as diatomaceous earth can be mixed with water to prepare a dispersion of silicon dioxide in water. The amount of silicon contained in this aqueous solution or dispersion is adjusted to 5% to 30% by mass, calculated as silicon dioxide, based on the total mass of the final catalyst, taking into account the amounts of other components added.

[0027] In this process, an acidic aqueous solution containing dissolved Ni is neutralized with a basic aqueous solution to form a Ni precipitate. At this time, a catalyst precursor containing Ni and Si is produced by mixing with an aqueous solution containing dissolved Si or a dispersion of SiO2 in water. At this time, Ni forms a poorly soluble compound such as a carbonate or hydroxide. A catalyst precursor containing Ni, Mg, and Si can be prepared by adding a water-soluble Mg salt, such as magnesium sulfate, magnesium chloride, or magnesium nitrate, to this catalyst precursor containing Ni and Si. Since the precursor containing Ni, Mg, and Si is produced as a solid in the liquid, the solid can be separated from the liquid if necessary. Furthermore, impurities contained in Ni, Mg, and Si can be removed by repeatedly redispersing and separating the separated solid in water.

[0028] In the catalysis step, the catalyst precursor obtained in the above step is calcined and reduced to prepare a catalyst.

[0029] In this step, the catalyst precursor is calcined to obtain an oxide catalyst. The method for calcining the catalyst precursor may be any method as long as the conditions are such that the Ni compound contained in the catalyst precursor is decomposed into nickel oxide. For example, by calcining in air at a temperature range of 300°C to 450°C, the Ni compound contained in the catalyst precursor can be decomposed into nickel oxide. Furthermore, by calcining for a time range of 1 hour to 24 hours, the Ni compound contained in the catalyst precursor can be decomposed into nickel oxide.

[0030] In this process, the oxide catalyst is reduced to obtain a catalyst. The oxide catalyst can be reduced under any conditions that reduce the nickel oxide contained in the oxide catalyst to metallic nickel. For example, reduction in hydrogen at a temperature range of 350°C to 450°C can reduce the nickel oxide contained in the oxide catalyst to metallic nickel. The metallic nickel promotes the hydrogenation reaction of aromatic compounds. Furthermore, if this catalyst is taken out into the air as is, the metallic nickel will react with oxygen in the air to turn into nickel oxide, and the resulting reaction heat may pose a risk of fire. Therefore, before taking it out into the air, a stabilization treatment is performed. The stabilization treatment forms a nickel oxide coating on the surface of the metallic nickel, which prevents the metallic nickel from reacting with oxygen in the air. Specifically, a nickel oxide coating can be formed on the surface of the metallic nickel by supplying a very small amount of oxygen to the catalyst and gradually increasing the oxygen concentration to 21%. When using the catalyst taken out through this process as a catalyst, the nickel oxide coating formed on the surface of the metallic nickel can be reduced and removed to promote the hydrogenation reaction of aromatic compounds.

[0031] In this step, the catalyst precursor can be molded into a desired shape before being calcined. For example, when molding into a columnar or similar shape, it can be molded by a conventionally known method such as tableting or extrusion molding. When extrusion molding is performed, if the moisture content in the molded body is reduced or the extrusion molding pressure is increased, the PV 1-60 In addition, when tableting, if the tableting pressure is increased, the PV 1-60 By using this method, PV 1-60 By lowering 1-60 PV as a percentage of 1-10 In addition, when molding into a spherical shape, the molding can be performed by a rolling granulation method or a method in which the catalyst precursor is dispersed in a solvent and then spray-dried.

[0032] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. [Measurement methods and evaluation methods] The catalysts obtained in each example were used as samples to carry out the following measurements and evaluations.

[0033] <Composition analysis> A sample was dissolved in acid, and the filtrate was diluted with water to an appropriate concentration, after which the contents of Ni, Mg, Si, and Al were measured using an ICP optical emission spectrometer (Agilent Technologies, 730ICP-OES, inductively coupled plasma optical emission spectroscopy). Note that each content was calculated based on the total amount of catalyst, with Ni converted to NiO, Mg converted to MgO, Si converted to SiO2, and Al converted to Al2O3.

[0034] <Specific Surface Area Measurement> The specific surface area of ​​the sample was calculated using the gas adsorption method (BET flow method). Specifically, a specific surface area measurement device (Mountec, Macsorb HM model-1220) was used. The sample was degassed in a pure nitrogen gas stream at 250°C for 40 minutes, and then maintained at liquid nitrogen temperature under a flow of a mixed gas of 30% nitrogen and 70% helium to allow equilibrium adsorption of nitrogen. The sample temperature was raised to room temperature while this mixed gas was being passed through, and the amount of nitrogen desorbed during this period was measured. The specific surface area was calculated by dividing this by the mass of the sample after measurement.

[0035] <Pore volume measurement> N2 adsorption measurement was carried out on the sample using the following method. From the adsorption isotherm obtained from the N2 adsorption measurement, the volume PV of pores with diameters in the range of 1 nm to 60 nm was calculated. 1-60 , the volume of pores with diameters in the range of 1 nm to 10 nm, PV 1-10 Also, PV 1-60 PV as a percentage of 1-10 Percentage of PV 1-10 / PV 1-60 ) was also calculated. Measurement method: Nitrogen adsorption method Measurement equipment: BEL SORP-mini II (Microtrac BEL) Sample amount: Approximately 0.1 g Pretreatment: 250°C, 3 hours or more (under vacuum) Relative pressure range: 0 to 1.0 Calculation method: BJH method

[0036] <Ni crystallite size> X-ray diffraction measurements were performed using an X-ray diffractometer manufactured by Rigaku Corporation (Rigaku Corporation MultiFlex). First, the sample to be measured was ground in a mortar and packed onto a sample plate. X-ray diffraction (Cu-Kα radiation source) measurements were performed under the following conditions: tube voltage 40 kV, tube current 20 mA, scan range 10-70°, divergence slit 1.0 mm, scattering slit 1.0 mm, receiving slit 0.3 mm, scan speed 4° / min. The Ni crystallite size was determined by detecting a diffraction peak with a peak top near 2θ = 44° in the X-ray diffraction measurement, and calculated using the Scherrer formula using analysis software (JADE Version 5.0).

[0037] <Particle size distribution> The particle size distribution of the sample was measured using a laser diffraction / scattering particle size distribution analyzer (LA-950V2) manufactured by HOLIBA. Specifically, the sample was placed in a solvent (water) so that the light transmittance was in the range of 70 to 95%, and the measurement was performed using ultrasonic waves for 1 minute, repeated 15 times. From the obtained particle size distribution, the volume median diameter (D 50 The refractive index of the sample was 1.6, and the refractive index of the solvent was 1.333.

[0038] <Ni on the catalyst surface 3+ Concentration > Ni on the sample surface 3+ The concentration was measured under the following conditions: Measurement method: XPS Measurement equipment: KRATOS ULTRA2 (Shimadzu Corporation) Radiation source: monochromatic Al Kα ray X-ray output: 75 W (15 kV, 5.0 mA) Pass energy: 20 eV Dwell time: 300 ms Energy step size: 0.1 eV Analysis software: ESCApe (Shimadzu Corporation) Analysis method: The spectrum obtained by XPS measurement was read into the analysis software, and matrix-corrected Ni, Ni 2+ , Ni 3+ The amount of Ni was calculated from the peaks assigned to 2p3 / 2 and Ni 2+ The amount of NiO peaks is attributed to 2p3 / 2, Ni 3+ The amount of Ni was calculated using the peaks assigned to 2p3 / 2 of Ni2O3. 3+ The concentration was calculated. 3+Concentration = Ni 3+ Amount / (Ni amount + Ni 2+ Amount + Ni 3+ amount)(%)

[0039] <Evaluation of Hydrogenation Activity for Aromatic Compounds> A resin hydrogenation reaction test was performed using the sample under the following conditions. <Conditions> 4.0 g of the sample was added to 166 g of a cyclohexane solution containing 40 wt % of T-REZ RD104 (manufactured by ENEOS Corporation), a copolymer of C4-5 hydrocarbon fraction and C8-10 aromatic hydrocarbon fraction, and the solution was placed in a stainless steel autoclave. The interior of the autoclave was purged with hydrogen gas, and the temperature was raised to 230°C while stirring at 600 rpm. Hydrogen was then injected into the autoclave until the pressure inside reached 5.0 MPa, and the hydrogenation reaction was carried out by maintaining the pressure at 5.0 MPa for 3 hours. After cooling, the sample and the reaction liquid were separated by filtration, and the reaction liquid was dried under reduced pressure to obtain the product after the hydrogenation reaction. <Hydrogenation rate of aromatic compound> The 1H-NMR spectra of the copolymer before and after the hydrogenation reaction were measured in deuterated chloroform using a nuclear magnetic resonance analyzer (manufactured by JEOL Ltd., trade name JNM-ECZ400R / SI, frequency 400 MHz), and the peak areas attributable to unsaturated bonds near 7.0 ppm and 5.5 ppm were determined, and the hydrogenation rate of aromatic compound was calculated using the following formula: Hydrogenation rate of aromatic compound = (1 - (peak area after hydrogenation reaction / peak area before hydrogenation reaction)) × 100 (%).

[0040] [Raw Materials Used] In the examples, the following raw materials were used: Nickel (II) sulfate hexahydrate (special grade, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) Sodium carbonate (special grade, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) Sodium silicate (No. 3, manufactured by Fuji Chemical Industries, Ltd.) Diatomaceous earth (Filter Cel, manufactured by Imerys) Magnesium sulfate (manufactured by Mai Chemical Industries, Ltd.) Magnesium oxide (special grade, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) Aluminum oxide (special grade, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)

[0041] Example 1 Catalyst Precursor Preparation Step: 900.0 g of nickel(II) sulfate hexahydrate was dissolved in 3.2 L of water, and the temperature was adjusted to 80°C to prepare an acidic aqueous solution. 2.8 L of water was poured into a 15 L stirring tank, and 716.7 g of sodium carbonate was dissolved therein. The temperature was adjusted to 80°C to prepare a basic aqueous solution. 1.7 L of water was poured into a 15 L stirring tank, and 141.7 g of sodium silicate was added thereto. The temperature was adjusted to 80°C to prepare a sodium silicate aqueous solution. Using a tube pump, the acidic aqueous solution and the basic aqueous solution were poured into the sodium silicate aqueous solution over 80 minutes to obtain a mixed solution. 133.3 g of magnesium sulfate was added to this mixed solution, and stirring was continued for 1.5 hours while maintaining the temperature at 80°C to obtain a precursor slurry. The precursor slurry was filtered under reduced pressure using a Nutsche funnel to obtain a cake-like precursor. The entire amount of this precursor was poured into 6 L of warm water adjusted to 40°C and washed by filtration. The same process was repeated until the electrical conductivity of the filtrate reached 1.0 mS / cm, at which point washing was stopped to obtain a cake-like precursor, which was then dried at 120°C for 12 hours in a box dryer to obtain a catalyst precursor.

[0042] <Catalyst Formation Step> The catalyst precursor was pulverized using a hammer crusher mill to obtain a powdered catalyst precursor. The powdered catalyst precursor and water were kneaded using a double-arm kneader to obtain a clay-like catalyst precursor. The clay-like catalyst precursor was extruded using an extrusion molding machine and molded into a 5.0 mm diameter cylindrical shape, which was then dried at 120°C to obtain a catalyst precursor molded body. The catalyst precursor molded body was calcined in a muffle furnace at 370°C for 6 hours to obtain an oxide catalyst. The oxide catalyst was further reduced in a hydrogen atmosphere at 430°C for 10 hours and subjected to stabilization treatment at 80°C to obtain a catalyst. The obtained catalyst was pulverized using a hammer crusher mill and sieved using a sieve with 100 μm openings. The catalyst that remained through the sieve was subjected to the measurements and evaluations described above. The results are shown in Table 1.

[0043] [Example 2] A catalyst was obtained in the same manner as in Example 1, except that in the catalyst precursor preparation step, the amount of sodium silicate added was 85.0 g and the amount of magnesium sulfate added was 266.7 g. The obtained catalyst was subjected to the above-mentioned measurements and evaluations. The results are shown in Table 1.

[0044] [Example 3] The powdered precursor obtained in the catalysis step of Example 1 was calcined in a muffle furnace at 370°C for 6 hours to obtain an oxide catalyst. This oxide catalyst was then reduced in a hydrogen atmosphere at 430°C for 10 hours and subjected to stabilization treatment at 80°C to obtain a catalyst. The obtained catalyst was subjected to the above-mentioned measurements and evaluations. The results are shown in Table 1.

[0045] Example 4 A catalyst was obtained in the same manner as in Example 1, except that in the catalysis step, a powdered catalyst precursor was molded into a cylindrical shape with a diameter of 5.0 mm and a height of 5.0 mm using a rotary tableting machine (HT-AP15SS-II manufactured by Hata Iron Works) with the tableting pressure adjusted to 1.8 to 2.0 kN during molding. The obtained catalyst was subjected to the above-described measurements and evaluations. The results are shown in Table 1.

[0046] Example 5 A catalyst was obtained in the same manner as in Example 1, except that 96.7 g of diatomaceous earth was added instead of sodium silicate and 76.7 g of magnesium sulfate was added in the catalyst precursor preparation step. The obtained catalyst was subjected to the above-described measurements and evaluations. The results are shown in Table 1.

[0047] [Example 6] A catalyst was obtained in the same manner as in Example 4, except that in the catalysis step, the tableting machine pressure was increased from 2.1 kN to 2.3 kN. The obtained catalyst was subjected to the above-mentioned measurements and evaluations. The results are shown in Table 1.

[0048] Comparative Example 1 A catalyst was obtained in the same manner as in Example 1, except that in the catalyst precursor preparation step, 108.2 g of sodium silicate, 592.0 g of sodium carbonate, and no magnesium sulfate were added. The obtained catalyst was subjected to the above-described measurements and evaluations. The results are shown in Table 1.

[0049] [Comparative Example 2] A catalyst was obtained in the same manner as in Example 1, except that magnesium sulfate was not added in the catalyst precursor preparation step, and that 126.4 g of magnesium oxide was added to 3,000.0 g of powdered catalyst precursor and kneaded in the catalysis step. The obtained catalyst was subjected to the above-mentioned measurements and evaluations. The results are shown in Table 1.

[0050] Comparative Example 3 A catalyst was obtained in the same manner as in Example 1, except that in the catalyst precursor preparation step, 103.3 g of aluminum oxide was added instead of sodium silicate and the amount of magnesium sulfate added was 47.9 g. The obtained catalyst was subjected to the above-described measurements and evaluations. The results are shown in Table 1.

[0051]

[0052] This application claims priority based on Japanese Patent Application No. 2024-033215, filed March 5, 2024, the disclosure of which is incorporated herein in its entirety by reference.

Claims

1. A catalyst for hydrogenating aromatic compounds, wherein the Ni content is in the range of 40% by mass to 90% by mass, calculated as NiO, relative to the total mass of the catalyst; the Si content is in the range of 5% by mass to 30% by mass, calculated as SiO2, relative to the total mass of the catalyst; the Mg content is in the range of 0.5% by mass to 20% by mass, calculated as MgO, relative to the total mass of the catalyst; and in a pore distribution obtained by a nitrogen adsorption method, the volume (PV) of pores having a diameter in the range of 1 nm to 10 nm is 1-10 ) is 0.2 mL / g or more and the pore volume (PV 1-60 ) The proportion of the aforementioned PV 1-10 The proportion of the catalyst is 60% or more.

2. Ni on the catalyst surface measured by X-ray photoelectron spectroscopy 3+ 10. The catalyst of claim 1, wherein the concentration is 60% or less.

3. Specific surface area is 100m 2 / g~300m 2 10. The catalyst of claim 1, wherein the .alpha.-hydroxybenzoate is in the range of 1000 ppm / g.

4. The catalyst according to claim 1, wherein the nickel crystallite size is in the range of 2 nm to 8 nm.

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