JPH07285892A - Production of cycloolefin - Google Patents

Abstract

PURPOSE:To produce a cycloolefin in high selectivity and efficiency by partially hydrogenating a monocyclic hydrocarbon in the presence of a catalyst produced by supporting ruthenium on a zirconia-modified silica carrier. CONSTITUTION:A monocyclic aromatic hydrocarbon (e.g. benzene) is partially hydrogenated preferably at 100-220 deg.C under hydrogen pressure of 0.5-10MPa in the presence of water and a catalyst produced by supporting ruthenium on a silica carrier modified with zirconia. The zirconia-modified silica carrier is preferably produced by supporting 0.5-10wt.% of zirconia on spherical silica e.g. by impregnation supporting method and drying and baking the product. The specific surface area of the spherical silica is 5-150m<2>/g and the volume ratio of the pores of 350-1,500Angstrom to the pores of 75-150,000Angstrom is >=55%. The maximum intensity of the relative intensity of ruthenium in the catalyst is preferably <=2.5 measured by a line analysis by an X-ray analyzer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for partially hydrogenating a monocyclic aromatic hydrocarbon to produce corresponding cycloolefins, particularly cyclohexene. Cycloolefin is a compound useful as a raw material for polyamide such as lactams and dicarboxylic acids, and as an important intermediate raw material for lysine, pharmaceuticals, agricultural chemicals and the like.

[0002]

2. Description of the Related Art As a method for producing cycloolefin,
Many methods such as partial hydrogenation reaction of monocyclic aromatic hydrocarbons, dehydration reaction of cycloalkanol, dehydrogenation reaction of cycloalkane, and oxidative dehydrogenation reaction have been known.
Among them, if the cycloolefin can be efficiently obtained by the partial hydrogenation of the monocyclic aromatic hydrocarbon, the reaction step becomes the most simplified, which is preferable in the process.

As a method for producing a cycloolefin by partial hydrogenation of a monocyclic aromatic hydrocarbon, ruthenium metal is mainly used as a catalyst and a hydrogenation reaction is generally performed in the presence of water and a metal salt. is there. As the ruthenium catalyst, a method in which metal ruthenium fine particles are used as they are (Japanese Patent Laid-Open Nos. 61-50930 and 62-45541,
(JP-A-62-45544), or a method using a catalyst in which ruthenium is supported on a carrier such as silica, alumina, barium sulfate, zirconium silicate (JP-A-57-57).
130926, JP 61-40226, JP 4-7.
4141) and many other proposals have been made.

[0004]

However, all of the conventional methods have some problems and are not necessarily industrially advantageous methods. The problem is that
The target cycloolefin selectivity is not sufficient, the activity of the catalyst is low and the cycloolefin cannot be efficiently produced, the durability of the catalyst is insufficient, and the handleability of the catalyst is poor. .

In many known methods, it is necessary to add a metal salt or an additive such as acid or alkali to the reaction system. These additives not only complicate the reaction system, but also accelerate corrosion of the reaction equipment and exhaustion and deterioration of the catalyst. Therefore, industrially, a method of adding no additives is also desired.

[0006]

DISCLOSURE OF THE INVENTION The present inventors have conducted extensive studies to solve the above-mentioned problems, and as a result, a catalyst in which ruthenium was supported on a silica support modified with zirconia was found to be a monocyclic aromatic hydrocarbon. They have found that they are extremely effective for partial hydrogenation, and have completed the present invention. That is, the present invention relates to a method for producing a cycloolefin, which comprises partially hydrogenating a monocyclic aromatic hydrocarbon in the presence of a catalyst in which ruthenium is supported on a silica support modified with zirconia and water.

The present invention will be described in detail below. The catalyst support used in the present invention is zirconia-modified silica. In the catalyst carrier used in the present invention, the type of silica is not particularly limited, but spherical silica is usually used. The particle size of the spherical silica can be selected to be an appropriate size in consideration of the reaction type. For example, in the case of a suspension bed, usually about 5 to 500 μm is preferable. The specific surface area of the carrier is not particularly limited,
It is usually 3 to 200 m ² / g, and particularly 5 to 150 m ² / g. Further, the silica carrier has a pore diameter of 75 to 15 when the pore volume and the pore distribution are measured by the mercury penetration method.
Pore diameter is usually 2 for a total pore volume of 10,000Å
The pore volume of 50 to 1,500Å is 55% or more, preferably 60% or more, and particularly preferably the pore diameter is 350 to 1,
It is preferable that the pore volume of 500Å is 55% or more. If the ratio of the pore diameters less than 250Å is too large, the selectivity tends to decrease, and if the ratio of the pore diameters exceeding 1500Å is too large, the activity tends to decrease, which is not preferable. Further, silica having physical properties in such a range is, for example, 600 at the step of catalyst preparation.
It is characterized in that it is difficult to crystallize even if it is fired at a high temperature of up to 1200 ° C.

The zirconia-modified silica carrier used in the present invention is a silica carrier in which zirconia is highly dispersed and supported on the entire surface including not only the outer surface of silica but also the surface inside pores. High-dispersion loading means a state in which the loaded zirconia has a relatively small crystallite size and is uniformly dispersed on the surface of silica. In this case, the average crystallite diameter of zirconia is usually 10 to 200Å, preferably 20 to 100Å. The average crystallite diameter here is, for example, from the spread of the diffraction width when the diffraction angle (2θ) of zirconia is around 30 ° by the powder X-ray diffraction method.
It is calculated by the formula of rrer.

The modification amount of zirconia is not particularly limited as long as the zirconia is supported on silica in a highly dispersed manner, but is usually 0.1 to 20% by weight, preferably 0.5. 10 to 10% by weight. If it is less than 0.1% by weight, the effect of modification by zirconia is not sufficiently exhibited and it is not effective for the partial hydrogenation reaction. Also, 20% by weight
Even if it is larger, the selectivity of cycloolefin may be rather lowered, which is not always effective for the partial hydrogenation reaction, and further, the economical disadvantage that the price of the carrier is increased is generated.

The method for preparing the carrier in the present invention may be any method as long as it is a method in which zirconia is dispersed and supported on the surface of silica as described above. However, generally, it is difficult to obtain such a state by a method of simply physically mixing silica and zirconia, and usually, a solution of a zirconium compound dissolved in water or an organic solvent, or a part or all of the zirconium compound is dissolved. There is used a method in which a solution obtained by hydrolyzing the above is supported on silica by suitably using a known impregnation supporting method or dip coating method, and then dried and calcined. Examples of the zirconium compound used here include zirconium halides, oxyhalides, nitrates, oxynitrates, hydroxides, and complex compounds such as zirconium acetylacetonate complexes and zirconium alkoxides. Further, the firing temperature here may be at least a temperature at which the zirconium compound used becomes zirconia, and is usually 600 ° C. or higher, particularly preferably 800 to 1200 ° C. However, if the temperature is higher than 1200 ° C. and fired at a higher temperature, the crystallization of silica becomes remarkable and the catalytic activity is lowered, which is not preferable.

Preparation of the catalyst is carried out in accordance with a commonly used method for preparing a conventional supported metal catalyst. That is, after dipping the carrier in the catalyst component liquid, the solvent is evaporated to evaporate the solvent to immobilize the active component, the evaporation dry solidification method, the catalyst active component liquid is sprayed while keeping the carrier dry, or the catalyst active A known impregnation-supporting method such as a method of filtering the carrier after immersing the carrier in the component liquid is suitably used.

As a raw material of ruthenium which is a catalytically active component, a ruthenium halide, nitrate, hydroxide or oxide, a complex compound such as ruthenium carbonyl or ruthenium ammine complex, and ruthenium alkoxide are used. In addition, as the solvent used for supporting the active ingredient at the time of preparing the catalyst, water or an organic solvent such as alcohol, acetone, tetrahydrofuran, hexane, or toluene is used.

Ruthenium, which is the active component of the catalyst, can be used alone, but other metal components may be co-supported and used. In this case, zinc, iron, cobalt, manganese, gold, lanthanum, copper and the like are effective as the component co-supported with ruthenium. As these metal compounds that are co-supporting components for ruthenium, halides, nitrates, acetates, sulfates of each metal, complex compounds containing each metal, and the like are used. In addition, these co-supported components are
It may be carried on the carrier simultaneously with the ruthenium raw material, may be carried after carrying ruthenium in advance, or may be carried after carrying these metals first and then carrying ruthenium afterwards.

The catalyst thus prepared is usually
Ruthenium is used after being reductively activated. As the reducing agent, hydrogen, carbon monoxide, alcohol vapor, hydrazine,
Known reducing agents such as formalin and sodium borohydride can be used. Preferably, hydrogen is used,
It is usually activated under the conditions of 80 to 500 ° C, preferably 100 to 450 ° C. If the reduction temperature is lower than 80 ° C, the reduction rate of ruthenium is significantly reduced, and if it is higher than 500 ° C, agglomeration of ruthenium is likely to occur, which causes a decrease in cycloolefin production yield and selectivity.

The prepared catalyst may be contact-treated with a specific metal salt to activate the catalyst. Examples of the metal salt used include Group 1 elements such as lithium, sodium and potassium, Group 2 elements such as magnesium, calcium and strontium, and manganese, iron and cobalt.
Metal salts such as zinc, copper, gold and zirconium, for example, weak acid salts such as carbonates and acetates, and strong acid salts such as hydrochlorides, sulfates and nitrates are used. The contact treatment is usually carried out by immersing the catalyst in an aqueous solution containing 0.01 to 100 times by weight, preferably 0.1 to 10 times by weight, the metal salt. The concentration of the metal salt in the aqueous solution is usually 1 × 10 ⁻⁵ to 1 times the weight of water, preferably 1 × 10 ^{5.
-4 to} 0.2 times by weight. The treatment conditions are usually from normal pressure to under pressure, room temperature to 250 ° C., preferably room temperature to 200.
It is carried out at 0 ° C. for usually 10 minutes to 20 hours, preferably 1 to 10 hours. The catalyst treatment atmosphere is usually an inert gas atmosphere or a hydrogen gas atmosphere, preferably a hydrogen gas atmosphere. The catalyst after the contact treatment is usually used after filtering the treated metal salt aqueous solution, washing with water and drying. Further, the catalytic activity can be further enhanced by performing a reduction treatment in a hydrogen gas atmosphere after drying.

The amount of ruthenium supported on the above catalyst is usually 0.001 to 10% by weight, preferably 0.05 to 5% by weight, based on the silica carrier modified with zirconia. When zinc, iron, cobalt, manganese, gold, lanthanum, copper, etc., which are co-supported components, are used, the atomic ratio to ruthenium is 0.01 to 20, preferably 0.05.
It is selected in the range of -10.

There are various reasons why the zirconia-modified silica carrier used in the catalyst of the present invention exerts a particularly effective effect on the partial hydrogenation reaction, as compared with a normal silica carrier without zirconia modification. It is presumed that this is because the ruthenium, which is the main component of the catalyst, can be uniformly dispersed and supported by modifying the surface with zirconia.

Conventional carriers, especially with a specific surface area of 100 m ² /
Silica having a relatively small specific surface area of g or less tends to cause non-uniform loading such as aggregation of catalyst components and segregation in the vicinity of the surface, but if the carrier of the present invention has the surface modified with zirconia, Even in such a case, uniform dispersion and loading can be carried out. The dispersibility of the supported state of the catalyst component can be analyzed by EPMA (X-ray microanalyzer). The dispersibility of the supported state of the catalyst component can be visually expressed from the EPMA element mapping diagram, but can also be quantitatively expressed by the EPMA line analysis method. That is, by cutting at a plane including the central portion of the catalyst particles that can be approximated to a spherical shape, and measuring the X-ray intensity of the catalyst component (ruthenium) for each region of the cut surface, the intensity of the central portion (I _center ) Relative intensity of each measurement point (I _n / I
_center ) and the frequency distribution of its relative intensities. If the dispersibility of the supported state of the catalyst component is uniform, the frequency distribution is concentrated in the vicinity of I _n / I _center = 1 and if not uniform,
The relative intensity ratio will increase, and the width of the frequency distribution will increase.

The uniform dispersibility of the catalyst component of the catalyst of the present invention in the supported state can be expressed by the above EPMA line analysis method. First, the maximum relative intensity is usually 4 or less, preferably 3 or less, and particularly preferably 2.5 or less. When the maximum relative strength exceeds 4, the catalyst component ruthenium is segregated on the outer surface of the carrier and is not uniformly dispersed. For example, silica alone as the catalyst carrier,
Alternatively, it is applicable when a physical mixture of silica and zirconia is used. Further, in the catalyst of the present invention, the relative strength is usually 0.6 to 1.4 and 60% or more of the total, preferably 7%.
It has a frequency distribution of 0% or more. More preferably, the relative intensity has a frequency distribution of 0.8 to 1.2, which is 65% or more of the whole.

The uniform dispersion and loading of the catalyst components as described above not only makes it possible to improve the cycloolefin selectivity and the activity per ruthenium, but also improves the peel resistance of ruthenium and prevents sintering. It is thought that this also affects the extension of the catalyst life. Further, by modifying the surface of silica with zirconia, the mechanical strength is also increased, so that the abrasion resistance is improved in the case of a suspension bed reaction or the like. The catalyst carrier used in the present invention is remarkably stable at high temperatures, and is stable even under heat treatment conditions such as silica crystallization or transformation of zirconia in silica alone or in a physical mixture of silica and zirconia.

In the present invention, water is present in the reaction system. The amount of water present is usually 0.01 to 10 times, preferably 0.1 to 5 times the volume ratio of the aromatic hydrocarbon. In addition, a method in which a metal salt is present in the reaction system in addition to the catalyst component is usually adopted. Examples of this metal salt include elements of Group 1 of the periodic table such as lithium, sodium and potassium, elements of Group 2 such as magnesium, calcium and strontium, and metal salts such as manganese, iron, cobalt, zinc and copper. Of these, salts of zinc, cobalt and lithium are particularly preferable. Examples of the type of metal salt include weak acid salts such as carbonates and acetates, and strong acid salts such as hydrochlorides, sulfates and nitrates. The amount of metal salt present is usually 1 × 10 ⁻⁵ to 1 times by weight, preferably 1 ×, with ^respect to coexisting water.
It is 10 ^{−4 to} 0.1 times by weight.

On the other hand, when the catalyst of the present invention is used, it is possible to obtain a high reaction result even if an additive such as a metal salt is not added to the reaction system. In general, in a reaction system containing an additive such as a metal salt, the catalytic activity per metal of ruthenium tends to be remarkably reduced when the amount of modification of silica with zirconia is small. In a system using the catalyst of the present invention and containing no additive such as a metal salt, the catalytic activity tends to remain high even if the modification amount of zirconia is reduced. In the reaction system containing no metal salt, the selectivity of the partial hydrogenation reaction generally tends to be slightly lower than that in the reaction system containing a metal salt. However, since the catalytic activity is very high, it is a simple reaction system, and it is possible to efficiently obtain the target product under the condition that the reaction equipment is less corrosive.

The monocyclic aromatic hydrocarbons to be used in the present invention include benzene, toluene, xylene, and lower alkyl group-substituted benzenes having about 1 to 4 carbon atoms. As the reaction conditions of the present invention, the reaction temperature is usually selected in the range of 50 to 250 ° C, preferably 100 to 220 ° C. When the temperature is 250 ° C or higher, the selectivity of cycloolefin is lowered, and when the temperature is 50 ° C or lower, the reaction rate is remarkably lowered, which is not preferable. The pressure of hydrogen during the reaction is usually 0.
It is selected from the range of 1 to 20 MPa, preferably 0.5 to 10 MPa. Usually, if it exceeds 20 MPa, it is industrially disadvantageous, while if it is less than 0.1 MPa, the reaction rate is remarkably reduced and it is uneconomical in terms of equipment. The reaction can be carried out in either a gas phase reaction or a liquid phase reaction, but is preferably a liquid phase reaction. The reaction system is not particularly limited, and it can be carried out batchwise or continuously using one or two or more reaction tanks.

[0024]

EXAMPLES Examples will be described below, but the present invention is not limited to these examples. The conversion rate and selectivity shown in Examples and Comparative Examples are defined by the following equations.

[Equation 1]

In the examples and comparative examples, the reaction time was set so that the conversion rate of the monocyclic aromatic hydrocarbon as the reaction raw material was around 30% except when the catalytic activity was extremely low, and the comparison was made. went. Further, "wt%" means "wt%".

Example 1 (Preparation of carrier) Zirconium oxynitrate dihydrate 0.8
A silica carrier (trade name CARIACT5 manufactured by Fuji Silysia Chemical Ltd.) was added to an aqueous solution prepared by dissolving 7 g in 20 ml of demineralized water.
0, average particle size of 50 μm, specific surface area of 70 m ² / g, pore volume of 75 to 150,000 Å, total pore volume of 250 to 1,500 Å, 95% of pore volume, (85% of the total pore volume of 75-150,000 Å diameter is 350-1500 Å)
After adding 8.0 g and immersing at room temperature, the water was distilled off with a rotary evaporator and dried. Next, this was charged into a quartz glass reaction tube, and the air was passed through the reaction tube at 1000 ° C for 4 hours.
It was calcined for an hour to prepare a 5 wt% zirconia-modified silica carrier. This carrier was analyzed by powder X-ray diffraction, and the average crystallite diameter of zirconia was calculated from the spread of the peak near the diffraction angle (2θ) of 30 degrees of zirconia by Scherer's formula, and it was 70Å.

FIG. 1 shows a powder X-ray diffraction diagram when the temperature of the carrier was raised from room temperature to 10 ° C./min to 1200 ° C. According to FIG. 1, a broad peak derived from silica is observed around 2θ = 22 °, and a peak derived from a metastable phase tetragonal crystal of zirconia is observed around 2θ = 30 °. Note that, 2θ = about 46 ° and 67 ° are background peaks derived from platinum used when preparing a sample for powder X-ray analysis. Further, FIG. 2 shows a powder X-ray diffraction diagram at 200 ° C. when the temperature was raised from 1200 ° C. to room temperature at 10 ° C./min after the temperature was raised to 1200 ° C. A peak similar to that in FIG. 1 is also observed in FIG. From the above Fig.1 and Fig.2,
It can be seen that the carrier is stable in an amorphous state, and silica crystallization and zirconia thermal transformation do not occur.

(Preparation of catalyst) The zirconia-modified silica carrier produced by the above method was added to an aqueous solution containing a predetermined amount of ruthenium chloride and zinc chloride, and after dipping at 60 ° C. for 1 hour, water was distilled off with a rotary evaporator. Removed and dried. The catalyst thus obtained (Ru-Zn
(0.5-0.5 wt%) / ZrO ₂ (5 wt%)-S
iO ₂ ) was charged into a Pyrex glass tube, and reduced and activated in a hydrogen stream at 200 ° C. for 3 hours. When the obtained catalyst was analyzed by EPMA (X-ray microanalyzer), it was confirmed that ruthenium metal (Ru) was uniformly dispersed on the surface of the carrier. In addition, EMPA analysis
Using JEOL JXA-8600M as a measuring device,
Electron gun acceleration voltage 20 kV, probe current 2.0 × 10
^-8 Å is set.

FIG. 3 shows an EPMA diagram of the obtained catalyst. The unit of the horizontal axis underline in the EPMA diagram indicates the ratio of the arbitrary distance of the catalyst from the center of the catalyst particle to the distance from the center of the catalyst particle to the outer surface. That is, the center is 0,
The outer surface is 1. The unit of the vertical axis is the relative intensity (I _n / I _c ) of each measurement point with respect to the intensity (I _center ) of the catalyst center.
_enter ) and the unit on the horizontal axis indicates the frequency distribution of the relative intensity as a frequency factor (%). From FIG. 3, in the catalyst, the relative intensities are all distributed at 0.6 to 1.4,
Moreover, 90% of the whole is distributed at a relative intensity of 0.8 to 1.2.

(Reaction) Internal volume 5 sufficiently replaced with nitrogen in advance
120 ml of water in a 00 ml stainless steel autoclave
1, 14.4 g of zinc sulfate heptahydrate, 6 g of the above catalyst, and 80 ml of benzene were charged. Further, hydrogen gas was introduced, and the reaction was carried out by a reaction pressure of 5.0 MPa, a temperature of 150 ° C., and an induction stirring method (1000 rpm). After the reaction, the mixture was cooled, only the oil phase was taken out, and the product was analyzed by gas chromatography. The results are shown in Table-1.

Comparative Example 1 Instead of the zirconia-modified silica carrier used in Example 1, the same silica as used in Example 1, which was not modified with zirconia, was air-calcined at 1000 ° C. for 4 hours. A catalyst was prepared in the same manner as in Example 1 except for the above. When the obtained catalyst was analyzed by EPMA, it was found that the dispersion of Ru was more uneven than that of the catalyst of Example 1, and Ru was significantly segregated in the surface layer of the carrier.

FIG. 4 shows an EPMA diagram of the obtained catalyst. Some of the catalysts have a relative intensity of more than 4, and the distribution of the relative intensity is wide. 65% of the whole is distributed in the relative intensities of 0.6 to 1.4, and 35% of the whole is distributed in the relative intensities of 0.8 to 1.2. Using this catalyst, a reaction was carried out in the same manner as in Example 1.
The results are shown in Table-1. From these results, Comparative Example 1 has lower activity and selectivity than Example 1, and the effect of the zirconia-modified silica carrier is clear.

[0033]

[Table 1]

Example 2 The reaction was carried out in the same manner as in Example 1 except that the amount of catalyst was changed to 3 g. However, the reaction time was set so that the conversion rate of benzene was around 30%. The results are shown in Table-2. Example 3 The reaction was performed in the same manner as in Example 2 except that cobalt sulfate heptahydrate was used in the same amount as in Example 2 instead of zinc sulfate heptahydrate. The results are shown in Table-2.

Example 4 An 8 wt% zirconia-modified silica carrier was prepared in the same manner as in Example 1 except that a predetermined amount of zirconium oxychloride octahydrate was used as the zirconia raw material when preparing the carrier. . This carrier was analyzed by powder X-ray analysis, and the average crystallite diameter of zirconia was determined by Scherer from the spread of peaks around the diffraction angle (2θ) of 30 degrees of zirconia.
It was 90Å as calculated by the formula. After that, a catalyst was prepared in the same manner as in Example 1.

FIG. 5 shows an EPMA diagram of the obtained catalyst. In the catalyst, all are distributed at a relative intensity of 0.6 to 1.2, and 95% of the whole is distributed at a relative intensity of 0.8 to 1.2. A reaction was carried out in the same manner as in Example 2 using this catalyst. The results are shown in Table-2.

Comparative Example 2 Instead of the zirconia-modified silica carrier used in Example 1, zirconia was added to the silica used in Example 1 in an amount of 8 wt% with respect to silica, and the mixture was physically mixed.
A catalyst was prepared in the same manner as in Example 1 except that air-calcined at 000 ° C for 4 hours was used as the carrier. This catalyst was analyzed by powder X-ray diffraction, and the average crystallite size of zirconia was calculated from the spread of the peak near the diffraction angle (2θ) of 30 degrees of zirconia by Scherer's formula, and was 179Å. A reaction was carried out in the same manner as in Example 2 using this catalyst. The results are shown in Table-2.

As a reference, FIG. 6 shows a powder X-ray diffraction diagram when the temperature of the physical mixture of silica-zirconia before zirconia modification was raised from room temperature to 1200 ° C. Further, FIG. 7 shows a powder X-ray diffraction diagram at 200 ° C. when the temperature was raised from 1200 ° C. to room temperature after the temperature was raised to 1200 ° C. A sharp peak derived from silica is observed in the vicinity of 2θ = 22 ° in both FIG. 6 and FIG. 7, indicating that the silica is crystallized. Further, the peak around 2θ = 30 ° showing the metastable tetragonal structure of zirconia in FIG. 6 becomes smaller in FIG. 7, and 2θ = 28 ° and 31 ° showing the monoclinic phase of zirconia.
A peak near the surface is appearing, confirming the thermal transformation of zirconia. The peaks near 2θ = 46 ° and 67 ° are background peaks derived from platinum used when preparing the sample for powder X-ray analysis. Comparative Example 3 A catalyst was prepared in the same manner as in Example 1 except that, instead of the zirconia-modified silica carrier used in Example 1, zirconium hydroxide was calcined in air at 1000 ° C. for 4 hours to obtain zirconia as a carrier. Was prepared. A reaction was carried out in the same manner as in Example 2 using this catalyst. The results are shown in Table-2.

Comparative Example 4 Instead of the zirconia-modified silica carrier used in Example 1, the silica used in Example 1 was impregnated with a commercially available zirconia sol solution (manufactured by Nissan Kagaku), followed by filtration, washing with water and drying. A catalyst was prepared in the same manner as in Example 1 except that the one that had been air-calcined at 1000 ° C. for 4 hours was used as the carrier. When this carrier was subjected to fluorescent X-ray analysis and the amount of zirconia was examined, the amount of zirconia was 25 wt% with respect to silica. This carrier was analyzed by powder X-ray diffraction, and the average crystallite diameter of zirconia was calculated from the broadening of the peak around the diffraction angle (2θ) of 30 degrees of zirconia.
It was 226Å as calculated by the formula of r. The results of carrying out the reaction in the same manner as in Example 2 using this catalyst are shown in Table-2.

[0040]

[Table 2]

* In Example 3, cobalt sulfate was used as an additive instead of zinc sulfate. Example 5 7 g of the catalyst prepared in Example 1 and 30 g of a 6 wt% zinc sulfate aqueous solution were placed in an autoclave, and the hydrogen pressure was 5.0 MPa.
The contact treatment was carried out at a temperature of 200 ° C. for 5 hours while stirring. After the treatment, the catalyst was cooled, the catalyst was taken out, washed with water, dried, and then subjected to reduction treatment under a hydrogen stream at 200 ° C. for 2 hours.

Table 3 shows the results of the reaction carried out in the same manner as in Example 1 except that the catalyst amount was changed to 6 g in Example 1 using the above catalyst. Example 6 7 g of the catalyst prepared in Example 1 and 30 g of a 6 wt% lithium sulfate aqueous solution were placed in an autoclave, and the hydrogen pressure was 5.0 MP.
a, contact treatment was carried out at a temperature of 150 ° C. for 5 hours while stirring. After the treatment, the catalyst was cooled, the catalyst was taken out, washed with water, dried, and then subjected to reduction treatment under a hydrogen stream at 200 ° C. for 2 hours.

The results of carrying out the reaction in the same manner as in Example 5 using the above catalyst are shown in Table 3.

[0044]

[Table 3]

Example 7 A catalyst was prepared in the same manner as in Example 1 except that the silica used in Example 1 was changed to the following. Silica carrier: Fuji Silysia Chemical Ltd., trade name CARIACT3
0, average particle size of 50 μm, specific surface area of 150 m ² / g, pore diameter of 250 to 1,500 Å, 60% of total pore volume of 75 to 150,000 Å, 12% of the total pore volume of 75-150,000Å in diameter and 350-1,500Å in pore diameter.

A reaction was carried out using this catalyst. That is, 150 ml of water, 18 g of zinc sulfate heptahydrate, and 18 g of zinc autoclave having an internal volume of 500 ml, which had been sufficiently replaced with nitrogen, were used.
3.75 g of the above catalyst and 100 ml of benzene were charged.
Furthermore, while supplying hydrogen gas, the reaction pressure is 5.0MP
a, the temperature was 150 ° C., the reaction was carried out for 55 minutes by the induction stirring method (1000 revolutions / minute), and the benzene conversion rate was 6
The selectivity was 0.0% and the cyclohexene selectivity was 58.0%.

Example 8 120 ml of water, 1 g of the catalyst prepared in Example 1 and 80 ml of benzene were charged into a stainless steel autoclave having an internal volume of 500 ml which had been sufficiently replaced with nitrogen. Further, by introducing hydrogen gas, the reaction pressure is 5.0 MPa, the temperature is 150
Table 4 shows the results of the reaction performed by the induction stirring method (1000 rotations / minute) at ℃. Example 9 A 2 wt% zirconia-modified silica carrier was prepared in the same manner as in Example 1 except that a predetermined amount of zirconium oxychloride octahydrate was used as the zirconia raw material when preparing the carrier. This carrier was analyzed by powder X-ray diffraction, and the average crystallite diameter of zirconia was determined by Scherer from the spread of peaks around the diffraction angle (2θ) of 30 degrees of zirconia.
It was 60Å as calculated by the formula. After that, a catalyst was prepared in the same manner as in Example 1. Table 4 shows the results of carrying out the reaction in the same manner as in Example 8 except that the catalyst amount was changed to 2 g in Example 8 using the above catalyst.

Example 10 7 g of the catalyst prepared in Example 1 and 30 g of a 6 wt% zinc sulfate aqueous solution were placed in an autoclave and the hydrogen pressure was 5.0 MPa.
Contact treatment was carried out at a temperature of 150 ° C. for 5 hours while stirring. After the treatment, the catalyst was cooled, the catalyst was taken out, washed with water, dried, and then subjected to reduction treatment under a hydrogen stream at 200 ° C. for 2 hours.

Table 4 shows the results of the reaction carried out in the same manner as in Example 1 except that the catalyst amount was changed to 2 g in Example 8 using the above catalyst. Comparative Example 5 The results of carrying out a reaction in the same manner as in Example 8 using this catalyst prepared in Comparative Example 1 are shown in Table 4. Comparative Example 6 In Comparative Example 1, a catalyst prepared in the same manner as in Comparative Example 1 except that zinc chloride was not used in the catalyst preparation was used, and the result of the reaction in the same manner as in Example 8 was shown. -4
Shown in.

[0050]

[Table 4]

[0051]

According to the method of the present invention, in the partial hydrogenation reaction of a monocyclic aromatic hydrocarbon, the activity per ruthenium metal is large, and cycloolefin can be obtained with a high selectivity. Further, the particle size of silica modified with zirconia can be set in a desired range, which is advantageous in industrial handling. Furthermore, since it is possible to support the catalyst component on the carrier in a highly dispersed manner, it is also effective in terms of exfoliation resistance of ruthenium metal, prevention of sintering, and extension of catalyst life, and the silica surface is modified with zirconia. Therefore, it is also advantageous in terms of carrier strength. Thus, according to the present invention, cycloolefin can be industrially advantageously produced.

[Brief description of drawings]

FIG. 1 is a powder X-ray diffraction diagram when the temperature of the silica carrier used in the catalyst of Example 1 was raised to 1200 ° C.

FIG. 2 is a powder X-ray diffraction diagram when the temperature of the silica carrier used in the catalyst of Example 1 was lowered from 1200 ° C. to 200 ° C.

FIG. 3 is an EMPA line analysis diagram of the catalyst of Example 1.

FIG. 4 is an EMPA line analysis diagram of the catalyst of Comparative Example 1.

5 is an EMPA line analysis diagram for the catalyst of Example 4. FIG.

FIG. 6 is a powder X-ray diffraction diagram when the temperature of the silica-zirconia physical mixture used for the catalyst of Comparative Example 2 was raised to 1200 ° C.

FIG. 7 is a powder X-ray diffraction diagram when the temperature of the physical mixture of silica-zirconia used in the catalyst of Comparative Example 2 was lowered from 1200 ° C. to 200 ° C.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Takao Maki 7-11-6 Kugenuma Kaigan, Fujisawa City, Kanagawa Prefecture

Claims (6)

[Claims] 1. A process for producing a cycloolefin, which comprises partially hydrogenating a monocyclic aromatic hydrocarbon in the presence of a catalyst in which ruthenium is supported on a silica support modified with zirconia and water. 2. The method of claim 1, wherein the monocyclic aromatic hydrocarbon is partially hydrogenated in the presence of a metal salt. 3. The method according to claim 1, wherein a silica carrier modified with 0.1 to 20% by weight of zirconia with respect to silica is used. 4. A silica carrier having a pore volume of 250 to 1,500 Å and a pore volume of 55% or more with respect to the total pore volume of 75 to 150,000 Å. The method according to any one of Items 1 to 3. 5. The method according to any one of claims 1 to 43, wherein the maximum value of the relative intensity (I _n / I _center ) of ruthenium by the line analysis method of an X-ray microanalyzer is 4 or less. 6. The relative intensity (I _n / I _center ) of ruthenium measured by an X-ray microanalyzer line analysis method is 0.6.
The method according to any one of claims 1 to 5, wherein the catalyst has a frequency distribution of 60% or more of the total in the range of from 1.4 to 1.4.