JPH08253433A - Production of cycloolefin - Google Patents

Abstract

PURPOSE: To stably produce cycloolefins in high selectivity and yield by partially reducing a monocyclic aromatic hydrocarbon using a ruthenium supported catalyst having a specific value or above of a metal dispersion degree. CONSTITUTION: A catalyst supported on a carrier and prepared by supporting ruthenium on the carrier in a state so as to provide the chemical adsorptivity for hydrogen of at least (0.6/1) expressed in terms of the ratio (H/Ru) of the number of the adsorbed hydrogen atoms to the total number of metallic ruthenium atoms in the catalyst is used as a hydrogenation catalyst to carry out partial hydrogenating reaction in partially reducing a monocyclic aromatic hydrocarbon with hydrogen in the coexistence of the hydrogenating catalyst consisting essentially of the ruthenium and water. The hydrogenating catalyst is prepared by using a ruthenium complex compound comprising a reactive ligand selected from carbonyl and an olefin as a precursor of the ruthenium.

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 stably produce corresponding cycloolefins, particularly cyclohexenes, in high yield. The obtained cycloolefins are
It is a compound useful as an important intermediate raw material for polyamide raw materials, lactams, lysines, pharmaceuticals, agricultural chemicals and the like.

[0002]

As a method for producing cyclohexenes, for example, (1) a method using a catalyst composition containing (1) water and an alkali agent and an element of Group VIII of the periodic table (Japanese Patent Publication No. 56-22).
No. 850), (2) nickel, cobalt, chromium,
Method using ruthenium catalyst supported on oxide of titanium or zirconium and using alcohol or ester as additive (Japanese Patent Publication No. 52-3933), (3)
A method of carrying out the reaction in the presence of a ruthenium catalyst and a neutral or acidic aqueous solution containing a salt of at least one cation selected from Group IA metals, Group IIA metals and manganese of the periodic table (Japanese Patent Publication No. 57-7607). ), (4) Partial hydrogenation in the presence of a catalyst having ruthenium supported on oxides such as silica and alumina, water and cobalt sulfate (JP-A-57-130926), (5)
One selected from the group consisting of lithium, cobalt, iron and zinc by using a catalyst in which at least one metal selected from the group consisting of iron, cobalt, silver and copper and ruthenium are supported on a barium sulfate carrier. The method for carrying out the reaction in the presence of the above metal sulfate and water
No. 1),

(6) At least one selected from silicon dioxide, titanium dioxide and aluminum oxide in the presence of a ruthenium-supported catalyst having barium sulfate as a carrier and water.
A method in which one or more kinds of metal oxides are allowed to coexist in a reaction system (Japanese Patent Publication No. 6-4545), (7) 200 as a hydrogenation catalyst
Using a metal ruthenium crystallite having an average crystallite size of angstrom or less and / or its agglomerated particles,
Method for carrying out reaction in the presence of water and at least one zinc compound (Japanese Patent Publication No. 19098/1990), (8) Ruthenium reduced product containing zinc in advance as hydrogenation catalyst, wherein zinc content Is 0.1 against ruthenium
A method has been proposed in which the reaction is carried out under acidic conditions in the presence of at least one water-soluble zinc compound and water, using a catalyst of 50% by weight (Japanese Patent Publication No. 2-16736).

[0004]

However, in these conventionally known methods, for example, in the above method (1), the reaction system is complicated and the conversion of the raw materials is improved in order to improve the selectivity of cyclohexenes. It is not practical because the rate and the reaction rate are significantly suppressed, and further, the corrosion resistance of the reactor is expected to be a problem, and in the methods (2) to (4), in terms of selectivity and yield. There is a problem that practical application is difficult unless there is a dramatic improvement. Furthermore (5),
In the method of (6), the yield of cyclohexenes is 3
Although it is as high as 0 to 40% and the method has improved catalyst life, the yield value is obtained at a high conversion rate, and the selectivity of cyclohexene itself is at most 50%. Before and after, in the current situation that the by-product cyclohexanes are already manufactured industrially at low cost,
It is hard to say that it is advantageous from an economic point of view.

On the other hand, in the methods (7) and (8),
Significant improvements have been made in selectivity and yield,
Since the fine particles mainly composed of metal ruthenium are used by themselves, agglomeration of the fine particle catalysts in the reaction system occurs, and it is difficult to be an economically stable production method.
Further, the reduction of reaction active points due to aggregation lowers the productivity per unit weight of ruthenium, which is not always economical.

[0006]

[Means for Solving the Problems] In order to solve the problems of the prior art, the inventors of the present invention have earnestly studied to obtain a catalyst system having a high selectivity for cyclohexenes, a high yield, and industrial stability. As a result, the following invention has been reached. That is, in the present invention, in the partial hydrogenation of a monocyclic aromatic hydrocarbon with hydrogen in the coexistence of a hydrogenation catalyst mainly composed of ruthenium and water, the chemisorption ability of hydrogen was adsorbed as the hydrogenation catalyst. The ratio (H / Ru) between the number of hydrogen atoms and the total number of ruthenium metal atoms in the catalyst is at least 0.6 /
The present invention provides a method for producing cycloolefin, which comprises using a carrier-supported catalyst supported in the state of 1.

Hereinafter, the present invention will be described in detail. In the present invention, as the hydrogenation catalyst, the chemisorption capacity of hydrogen is represented by the ratio (H / Ru) between the number of adsorbed hydrogen atoms and the number of all-metal ruthenium atoms in the catalyst, and is at least 0.6 / 1
A carrier-supported catalyst that is supported in the following state is used.

Generally, in a catalyst in which a metal is supported on a carrier, the catalytic activity per metal is increased, the reaction selectivity or the stability of the active metal substance is improved due to the dispersion effect of the metal supported. Is empirically known. In addition, the metal fine particle crystals on the carrier show a unique size, morphology and surface structure depending on the precursor compound of the active species metal, the surface properties of the carrier metal oxide, the preparation method and conditions, etc. Is known to be greatly involved in reactivity. Furthermore, when the active metal is highly dispersed on the carrier, it has been found that the reaction activity and the reaction selectivity are improved due to changes in gas adsorption characteristics caused by the interaction with the carrier. The influence of the state of the fine metal particles of the carrier-supported catalyst on the reactivity is the ruthenium having an average crystallite size of 30 to 200 angstroms described in JP-A-63-243038. It may be an important factor in the partial hydrogenation reaction so that the supported catalyst is effective.

On the other hand, according to the studies by the present inventors, the dispersity (H / Ru) of ruthenium metal, which is defined by the chemisorption capacity of hydrogen of the catalyst, affects the partial hydrogenation reaction of monocyclic aromatic hydrocarbons. , Especially the selectivity and yield of cyclohexenes,
Furthermore, it was found that the catalyst life was remarkably different, and the dispersity of ruthenium, which is advantageous for the partial hydrogenation reaction, was
It was concluded that a carrier-supported catalyst supported in a state of at least 0.6 / 1, preferably 0.8 / 1 was particularly effective.

Here, the hydrogen-chemisorption amount (H / Ru) is measured according to the chemisorption method, which is a general method for estimating the number of exposed atoms (dispersion degree) of the supported metal catalyst, Specifically, it is calculated from the ratio of the number of chemisorbed hydrogen atoms to the total number of ruthenium atoms in the catalyst from the amount of chemisorption of hydrogen in the catalyst measured by the measuring method described later.

By placing ruthenium in a highly dispersed state on the carrier as described above, the catalyst system becomes extremely advantageous for the selectivity and yield of the partial hydrogenation reaction, and further for the catalyst life, and also the ruthenium unit. The reaction rate per weight, that is, the productivity is also improved by the increase in the metal surface area due to the high dispersion, compared with the low-dispersion catalyst obtained by the general method, so that the selectivity and the activity are high. It was possible to produce cycloolefin.

The hydrogenation catalyst in the present invention may be prepared by various methods by appropriately selecting the amount of metal supported, which is a factor controlling the dispersibility of the metal, the surface properties of the carrier, the metal precursor, the supporting method and the preparation conditions. In particular, when a ruthenium complex is used as a precursor compound for ruthenium, preferable results can be obtained. Here, the ruthenium complex refers to a ruthenium complex compound composed of at least one kind of reactive ligand selected from carbonyl and olefin, and includes, for example, ruthenium carbonyl and ruthenium olefin complex, and a carbonyl group having a hydride ion, Examples thereof include ruthenium carbonyl compounds partially substituted with a ligand such as olefin.

Specifically, ruthenium carbonyl complexes such as pentacarbonyl ruthenium and dodecacarbonyl triruthenium, tetra-μ-hydridododecacarbonyl tetraruthenium, tetracarbonylbis (η-cyclopentadiene) diruthenium, tetracarbonylbis ( η
-Pentamethylcyclopentadiene) diruthenium,
Ruthenium carbonyl compound complexes represented by tricarbonyl (cyclooctatetraene) ruthenium, tricarbonyl (1,5-cyclooctadiene) ruthenium, dicarbonylbis (η-allyl) ruthenium, and the like,

Bis (η-cyclopentadienyl) ruthenium, (cyclopentadienyl) (pentamethylcyclopentadienyl) ruthenium, hydride (cyclopentadienyl) (1,5-cyclooctadiene) ruthenium, (η -Cyclooctatriene) (η-cyclooctadiene) ruthenium, (η-benzene) (η-1,3cyclohexadiene) ruthenium, bis (η-allyl)
There are ruthenium olefin complexes represented by (η ⁴ -norbornadiene) ruthenium and the like, and dodecacarbonyltriruthenium, tetra-μ-hydridododecacarbonyltetraruthenium, tricarbonyl (1,5-cyclooctadiene) ruthenium, (η- Cyclooctatriene) (η-cyclooctadiene) ruthenium is preferably used, and in particular, dodecacarbonyltriruthenium gives favorable results in the selectivity and yield of cyclohexenes.

The reason why the highly dispersed ruthenium catalyst thus obtained exerts an excellent effect on the partial hydrogenation reaction is not always clear, but the increased interaction with the carrier and the ruthenium supported by the highly dispersed support are not clear. It can be considered that effective active sites are formed for the selectivity of cyclohexenes, the yield, and the life of the catalyst due to the improvement of particle stability and the reduction of poisoning by residual root ions such as chlorine. .

As a method for preparing the above-mentioned catalyst using the ruthenium complex as a catalyst precursor, the catalyst is prepared by utilizing the reactivity between the ruthenium complex having a reactive ligand and the surface of the carrier metal oxide. For example, a complex compound is formed on the surface of the carrier metal oxide by the surface reaction of some of the reactive ligands of the ruthenium complex and the surface functional groups of the carrier metal oxide (eg, hydroxyl group, Lewis acid, basic points). Immobilize and subject this complex-supported catalyst to heating-exhaust treatment or hydrogen reduction treatment,
By removing the metal ligand, highly dispersed ruthenium crystals are formed on the metal oxide.

A specific method for preparing the catalyst will be described below. The method for immobilizing the ruthenium complex having a reactive ligand on the surface of the support is performed according to the method for preparing a supported catalyst that is usually used. For example, using a solution of a ruthenium complex compound dissolved in a suitable solvent, a chemical wet method in which it is adsorbed on a carrier by a known impregnation method such as an evaporation dryness method, an adsorption method, an immersion method, or a spray method, a ruthenium complex compound crystal A chemical vapor phase method or the like in which a sublimation is performed and a direct vapor phase reaction with a carrier is used. Water or tetrahydrofuran, n-hexane, acetone, alcohol or the like is used as a solvent when the chemical wet method is used for preparing the catalyst.

The catalyst in which the ruthenium complex compound is immobilized on the carrier as described above is used in order to desorb the ruthenium ligand by adding heat-activation treatment in an inert gas, vacuum or hydrogen. . Heating temperature is 100-500
C., preferably 130-400.degree. C. is chosen. The above-mentioned atmosphere during the heat treatment is performed alone or in combination. When a valuable ruthenium complex compound is used, reduction treatment with hydrogen is preferably performed.

Ruthenium, which is the active species of the catalyst, can be supported alone on the carrier, but other metal species may be co-supported during or after the preparation stage of the catalyst. Examples of the metal species include Zn, Cr, and M, which are known per se.
N, Co, Ni, Fe, Cu and the like are preferably used.
In particular, co-supporting a metal compound consisting of Zn, Mn and Fe gives favorable results in the selectivity and yield of cycloolefins. As compounds of Zn, Mn, and Fe that are co-supporting components, halides, nitrates, sulfates, acetates, etc. of each metal are used.

Although various carriers can be used,
A metal oxide, a hydroxide of an oxide, or a composite oxide is preferably used. Specifically, for example, Zr, H
f, Si, Al, Nd, Ta, Cr, Ti, Fe, C
It is an oxide of o, Ga, a hydrate of an oxide, or a composite oxide of these. In particular, ZrO ₂ , SiO ₂ , TiO ₂
Significantly affects the selectivity and yield of cyclohexenes. As other carriers, metal salts such as magnesium carbonate, barium carbonate and barium sulfate, which are substantially insoluble in the reaction system, activated carbon, and resins such as Teflon can be used.

The supported amount of ruthenium metal is 0.01 to 20% by weight, preferably 0.1 to 1 based on the carrier.
0% by weight. When using a co-supported component, Zn, M
The content of n and Fe is 0.
It is 01 to 20, preferably 0.1 to 10.

In the present invention, the presence of water is necessary. The amount of water varies depending on the reaction mode, but is 0.01 to 1 relative to the generally used monocyclic aromatic hydrocarbon.
It is possible to coexist with 100 times by weight. However, under the reaction conditions, it is preferable that the organic phase containing the raw material and the product as main components and the liquid phase containing water form two phases.
The coexistence of a very small amount of water or a coexistence of an extremely large amount of water under the reaction conditions reduces the effect,
Further, if the amount of water is too large, it is necessary to make the reactor large. Therefore, it is desirable to coexist 0.5 to 20 times by weight practically.

Further, in the present invention, as in the known method already proposed, salts of various metals such as Mn, Fe, Zn and Co of the periodic table IA group element, IIA group element and the like are added. Good. In particular, the presence of Zn salts gives good results. Many zinc compounds can be used regardless of whether they are water-soluble or poorly water-soluble. As the water-soluble zinc compound, zinc sulfate, zinc chloride, strong acid salts typified by zinc nitrate, weak acid salts typified by zinc acetate, and various ammonium complexes can be used, but strong acid salt aqueous solutions are particularly preferably used. It

The coexistence of a water-soluble zinc compound has an effect of improving the selectivity of cycloolefins, and in the case of a strong acid salt, this effect is more remarkable. Zinc chloride and zinc sulfate are preferable, and zinc sulfate is most preferable. It can be said to be preferable.
It is not necessary that all of the strong salt of zinc is dissolved in the reaction system, but the concentration of the aqueous solution is usually 1
Used in the concentration range from × 10 ⁻³ wt% to saturated solubility. When using a zinc sulfate aqueous solution, it is more preferable to use it in a concentration range of 0.1 to 30% by weight. Further, a basic zinc salt which is a sparingly water-soluble zinc compound may be allowed to coexist. Here, the basic zinc salt refers to a zinc salt containing a conjugate base residue of various acids and a hydroxyl group or an oxygen atom which is regarded as a negative component other than this.

Specifically, ZnSO ₄ .1 / 2ZnO,
ZnSO ₄ · ZnO · H ₂ O (ZnSO ₄ · Zn (O
H) ₂ or Zn ₂ (OH) ₂ SO ₄ ), ZnSO ₄ ·
3ZnO, ZnSO ₄ 3ZnO 3H ₂ O (ZnSO
_{4 · 3Zn (OH) 2)} , ZnSO 4 · 3ZnO · 6H
_{2 O, ZnSO 4 · 3ZnO ·} 7H 2 O, ZnSO 4 ·
3ZnO / 8H ₂ O, ZnSO ₄ / 4ZnO / 4H ₂ O
(ZnSO ₄ .4Zn (OH) ₂ ) and other basic zinc sulfate,

ZnO.3ZnCl ₂ .H ₂ O, ZnO.
ZnCl ₂ · nH ₂ O (n is 1 or 1.5), 3Zn
O · 2ZnCl ₂ · 11H ₂ O, 2ZnO · ZnCl ₂
・ 4H ₂ O, 5ZnO ・ 2ZnCl ₂・ 6H ₂ O, 5Z
nO · 5ZnCl ₂ · 8H ₂ O, 3ZnO · ZnCl ₂
NH ₂ O (n is 2, 3, 4, 5 or 8), 4ZnO
.ZnCl ₂ .nH ₂ O (n is 4, 6 or 11), 9
ZnO ・ 2ZnCl ₂・ 12H ₂ O, 5ZnO ・ ZnC
l ₂ · nH ₂ O (n is 6, 8 or 29), 11ZnO
・ 2ZnCl ₂ , 6ZnO ・ ZnCl ₂・ nH ₂ O (n
6 or 10), ZnO · ZnCl ₂ · 10H ₂ O,
9 ZnO.ZnCl ₂ .nH ₂ O (n is 3 or 1
4), ZnBr ₂ .4ZnO.nH ₂ O (n is 10, 1
3 or 29), ZnBr ₂ .5ZnO.6H ₂ O,
ZnBr ₂ · 6ZnO · 35H ₂ O, ZnI ₂ · 4Zn
(OH) ₂ , ZnI _2.5 ZnO 11H ₂ O, ZnI
Basic zinc halide typified ₂ · 9ZnO · 24H ₂ O,

8ZnO.N ₂ O ₅ .4H ₂ O, 4ZnO
・ N ₂ O ₅・ 4H ₂ O, ₅ ZnO ・ N ₂ O ₅・ 4H
₂ O, 4ZnO ・ N ₂ O ₅・ 4H ₂ O, 5ZnO ・ N ₂
O ₅ · 5H ₂ O and 6H ₂ O, 5ZnO · N ₂ O ₅ ·
Basic zinc nitrate represented by 5H ₂ O, etc.
There are basic zinc acetate and the like, and basic zinc sulfate and basic zinc chloride are preferably used, and basic zinc sulfate is particularly preferable. When such a basic zinc salt is used, the hydrogenation catalyst is 1 × 10 ⁻⁶ to 1 times by weight, preferably 1 × 10 ^{−3 to} 0.
The reaction is carried out by coexisting 5 times by weight. In particular, sharing zinc sulfate with basic zinc sulfate is advantageous in increasing the selectivity and yield of the reaction.

Further, in the present invention, it is preferable to keep the coexisting aqueous phase under neutral or acidic conditions for the reaction. When the aqueous phase becomes alkaline, the reaction rate is particularly lowered, which is not preferable. Preferably, the pH of the aqueous phase is 0.5 to less than 7, more preferably 2 to
It is 6.5.

The monocyclic aromatic hydrocarbon in the present invention means
Benzene, toluene, xylenes and lower alkylbenzenes having 4 or less carbon atoms. The purity of the raw material itself does not need to be particularly high, and inclusion of cycloparaffins, lower paraffin hydrocarbons, etc. does not cause any problems.

The partial hydrogen reaction in the present invention is usually carried out continuously or batchwise by a liquid phase suspension method, but can also be carried out by a stationary phase system. The reaction conditions are appropriately selected depending on the type and amount of the catalyst and additives used, but the hydrogen pressure is usually 1 to 200 Kg / cm ² G, preferably 10 to 10
In the range of 0Kg / cm ² G, the reaction temperature is room temperature to 25
The temperature is 0 ° C, preferably 100 to 200 ° C. Further, the reaction time may be appropriately selected by setting a substantial target value of the selectivity and yield of the desired cyclohexenes,
There is no particular limitation, but it is usually several seconds to several hours.

[0031]

In the present invention, as the hydrogenation catalyst,
Support carried in a state in which the chemisorption capacity of hydrogen is at least 0.6 / 1 expressed as a ratio (H / Ru) between the number of adsorbed hydrogen atoms and the number of all-metal ruthenium atoms in the catalyst By carrying out the reaction using a catalyst, cycloolefins can be obtained from a monocyclic aromatic hydrocarbon with high selectivity and yield, and further, the system has a significantly improved catalyst life, which is of great industrial value. Will be high.

[0032]

EXAMPLES Next, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples.

Example 1 (Catalyst preparation) Commercially available Ru ₃ (CO) under nitrogen atmosphere
₁₂ (1.1 g) was dissolved in 300 ml of tetrahydrofuran to obtain a uniform solution of ruthenium carbonyl. Commercially available ZrO ₂ powder (10 g) was put into this, dispersed with stirring, adsorbed at room temperature for 12 hours, then charged in a rotary evaporator, and tetrahydrofuran was distilled under reduced pressure at 80 ° C. Then, the vacuum evacuation process was performed for another 2 hours. The evaporated dry solid thus obtained was charged into a glass reaction tube made of Pyrex, the temperature was raised to 200 ° C. while hydrogen was flowed at a flow rate of 100 ml / min, and the temperature was kept for 2 hours to perform de-CO treatment. Perform 5% Ru / ZrO
₂ supported catalysts were obtained.

(Measurement of Dispersion Degree) The amount of chemisorption of hydrogen of the obtained catalyst was measured based on the static gas adsorption method using an adsorption measuring device Akiyuso 2100-02 manufactured by Shimadzu Corporation. Specifically, an accurately weighed catalyst was put into a sample tube, and as pretreatment, after evacuation at 100 ° C. for about 12 hours, hydrogen gas was introduced at about 700 mmHg and reduction treatment was performed for about 1 hour. Next, vacuum evacuation is performed at 200 ° C. for about 24 hours to desorb the adsorbed hydrogen, cool it to room temperature, introduce hydrogen into the sample tube, and change the equilibrium adsorption pressure of hydrogen to change the adsorption isotherm. Then, the amount of adsorption was measured. Furthermore, assuming that one hydrogen atom is adsorbed to one ruthenium atom, the ratio (H / Ru) between the number of adsorbed hydrogen atoms obtained and the total number of ruthenium atoms in the catalyst is calculated, and this is calculated as the surface metal. The dispersity of ruthenium was used. As a result of measuring the dispersity of 5% Ru / ZrO ₂ obtained above by such a method,
It was 0.97.

(Partial hydrogenation reaction) Next, the catalyst (2.0 g) obtained above, ZnSO ₄ .7H ₂ O (50 g) and water (280 ml) were applied to the inner surface with Teflon coating, and the internal volume was 1000 ml. Charge the autoclave of the
After replacing the inside of the toclave with nitrogen and then with hydrogen,
The temperature was raised to 150 ° C with stirring, and then benzene 140m
1 together with hydrogen to a total pressure of 50 kg / cm ² G,
While maintaining the reaction temperature at 150 ° C., a partial hydrogenation reaction of benzene was carried out under vigorous stirring, a part of the content was extracted with time, and the composition of the oil phase was analyzed by gas chromatography. Table 1 shows the results. It is obvious that this is much superior in cyclohexene selectivity and yield as compared with (1) to (6) described in the above-mentioned prior art. On the other hand, the reaction amount of benzene per unit weight of ruthenium in this example is about 1500 g / g-ruthenium.hour based on the benzene conversion rate of 60%, which is described in the above-mentioned conventional techniques (7), (8). It is clear that the cyclohexene selectivity and yield are comparable to those in Example 1), and the activity is significantly improved.

Example 2 Ru ₃ (CO) ₁₂ (2.0 g) and n-octane 300 m
l was added, and the mixture was refluxed at 90 ° C. for 1 hour while blowing hydrogen, and after confirming that the absorption of the starting material at 2061 cm ^{−1 in} the reaction solution was gone, the solution was concentrated and Ru was added.
₄ (μ-H) ₄ (CO) ₁₂ crystals (1.4 g) were obtained. A 5% Ru / ZrO ₂ supported catalyst was prepared in the same manner as in Example 1 except that the thus obtained crystal (1.0 g) was used, and the reaction was carried out in the same manner. The ruthenium dispersity of this catalyst and the reaction results are shown in Table 1.

Example 3 RuCl ₃ .3H ₂ O (1.6 g) under an argon atmosphere
Methanol solution (36 ml) in zinc powder (18 g),
Ru (1,3,3) was added dropwise to a mixed solution of 1,5-cyclooctadiene (38 ml) in methanol (15 ml) and refluxed at 70 ° C. for 2 hours, followed by column purification and recrystallization.
_{5-C 8 H 10) (} 1,5-C 8 H 12) crystals (1.8 g)
I got A 5% Ru / ZrO ₂ supported catalyst was prepared in the same manner as in Example 1 except that the thus obtained crystal (1.6 g) was used, and the reaction was carried out in the same manner. The ruthenium dispersity of this catalyst and the reaction results are shown in Table 1.

Example 4 Ru ₃ (CO) ₁₂ (2.9 g) and 1,5-cyclooctadiene (45 ml) were reacted under reflux of benzene for 10 hours under an argon atmosphere, and then at 30 ° C. under reduced pressure. The solvent was distilled off, pentane was added to the dried solid matter to extract the product, and then column purification and sublimation were carried out again to obtain Ru (C
O) ₃ (η-C ₈ H ₁₂ ) crystals (2.0 g) were obtained. The crystals (1.5 g) thus obtained were used,
A 5% Ru / ZrO ₂ supported catalyst was prepared in the same manner as in Example 1, and the reaction was carried out in the same manner. The ruthenium dispersity of this catalyst and the reaction results are shown in Table 1.

Example 5 The procedure of Example 1 was repeated, except that the amount of ruthenium supported was 1% and the amount of catalyst used in the reaction was 5.0 g. Table 1 shows the results.

Examples 6 and 7 Preparation and reaction were carried out in the same manner as in Example 1 except that commercially available SiO ₂ or TiO ₂ was used instead of ZrO ₂ . Table 1 shows the results.

Comparative Example 1 RuCl ₃ .3H ₂ 0 (1.4 g) was dissolved in 300 ml of water to obtain a uniform solution of ruthenium chloride. The same ZrO ₂ powder (10 g) as that used in Example 1 was put into this, impregnated at 60 ° C. for 1 hour, charged into a rotary evaporator, and kept at 80 ° C. under reduced pressure. The water was distilled off. The evaporated dry solid thus obtained was charged into a glass reaction tube made of Pyrex, and the temperature was raised to 300 ° C. while flowing hydrogen at a flow rate of 100 ml / min, followed by reduction and activation by holding for 3 hours. Then, 5% Ru / ZrO ₂ using ruthenium chloride as a precursor was prepared. Other than using the catalyst thus obtained (2.0 g),
The reaction was carried out in the same manner as in Example 1. The results are shown in Table 2.

Comparative Example 2 The procedure of Comparative Example 1 was repeated except that the amount of ruthenium supported was 1% and the amount of catalyst used in the reaction was 5.0 g. The results are shown in Table 2.

COMPARATIVE EXAMPLE 3 The procedure of Comparative Example 1 was repeated except that the TiO ₂ used in Example 7 was used instead of ZrO ₂ .
The results are shown in Table 2. From these, the catalyst system prepared by using the ruthenium complex according to the present invention as a precursor has a completely different ruthenium dispersity and cyclohexene selectivity and yield as compared with a system using ruthenium chloride which is usually performed. Is clear.

[0044] Example _{8 ZnSO 4 · 7H 2 O ZnCl} 2 in place of (23 g)
The reaction was performed in the same manner as in Example 1 except that Table 3 shows the results.

Example 9 As a cocatalyst, ZnSO ₄ .4Zn (OH) ₂ (0.2
The reaction was performed in the same manner as in Example 1 except that g) was further added. Table 3 shows the results.

[0046] Example _{10 Zn (NO 3) 2 ·} 6H 2 O and (1.5 g) 300 ml
Was dissolved in water to obtain a uniform solution of zinc nitrate. The same ZrO ₂ powder (10 g) as that used in Example 1 was put into this, impregnated at 60 ° C. for 1 hour, charged into a rotary evaporator, and kept at 80 ° C. under reduced pressure. The water was distilled off. The evaporated dry matter thus obtained was charged into a Pyrex glass reaction tube, heated to 400 ° C. and kept for 3 hours while flowing hydrogen at a flow rate of 100 ml / min to carry out a reduction treatment. . The Zn / ZrO ₂ thus obtained was prepared in the same manner as in Example 1 except that ZrO ₂ was used as a catalyst carrier instead of ZrO ₂ , and the reaction was carried out in the same manner. Table 3 shows the results.

Examples 11 and 12 Mn (NO ₃ ) instead of Zn (NO ₃ ) ₂ .6H ₂ O
₂ · 6H ₂ O (1.5g) or Fe (NO _{3) 2} ·
The reaction was carried out in the same manner as in Example 9 except that 6H ₂ O (2.0 g) was used. Table 3 shows the results.

Example 13 5% Ru / ZrO ₂ catalyst prepared in Example 1 (5.0
_{g), ZnSO 4 · 7H 2} O (180g), water (100
0 ml) was charged into a tank-type flow reactor having an oil-water separation tank as an auxiliary tank and whose inner surface was subjected to Teflon coating, and at 150 ° C. and hydrogen pressure of 50 kg / cm ² G, catalyst poisoning substances such as sulfur were added. 1000m of benzene not containing
The reaction product was continuously taken out from the oil / water separation tank by supplying 1 / Hr and continuously performing a partial hydrogenation reaction of benzene. 100 hours after the start of the flow reaction, 300 hours after, and 5
The reaction results after 00 hours are shown in Table 4.

Examples 14 and 15 5% Ru / TiO ₂ catalyst prepared in Examples 7 and 3 (20%
g) or 5% Ru / ZrO ₂ catalyst (5.0 g) was used, and a continuous reaction was carried out in the same manner as in Example 13. The results are shown in Table 4.

Comparative Examples 4 and 5 5% Ru / ZrO ₂ catalyst prepared in Comparative Examples 1 and ₂ (15
g) or 1% Ru / ZrO ₂ catalyst (30 g) was used, and a continuous reaction was carried out in the same manner as in Example 13.
The results are shown in Table 4. According to Examples 13, 14, 15 and Comparative Examples 4 and 5, the catalyst system in the method of the present invention not only exhibits an excellent effect on the selectivity and yield of cyclohexene, but also is extremely stable in a long-term flow reaction. Clearly there is.

[0051]

[Table 1]

[0052]

[Table 2]

[0053]

[Table 3]

[0054]

[Table 4]

Claims (3)

[Claims] 1. A hydrogen atom having a chemisorption capability of hydrogen as a hydrogenation catalyst when partially reducing a monocyclic aromatic hydrocarbon with hydrogen in the coexistence of a hydrogenation catalyst mainly composed of ruthenium and water. Number and the number of all-metal ruthenium atoms in the catalyst (H / Ru), at least 0.
A method for producing cycloolefin, which comprises using a carrier-supported catalyst supported in a state of 6/1. 2. The hydrogenation catalyst is prepared using a ruthenium complex composed of at least one reactive ligand selected from carbonyl and olefin as a precursor. 1. The method for producing cycloolefin as described in 1. 3. The method for producing cycloolephine according to claim 1, wherein at the time of partial reduction, at least one zinc compound is allowed to coexist and the reaction is carried out under neutral or acidic conditions.