JP2000053598A - Production of cycloolefin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a cycloolefin by the continuous hydrogenation reaction of a monocyclic aromatic hydrocarbon in the presence of metal ruthenium as a catalyst, capable of stably producing the cycloolefin in a high selectivity. SOLUTION: This method for producing a cycloolefin comprises reacting a monocyclic aromatic hydrocarbon with hydrogen in the presence of a catalyst system, water and a metal sulfate, especially zinc sulfate, under a neutral or acidic condition. The catalyst system comprises a non-supported hydrogenation catalyst containing zinc and consisting mainly of particles comprising metal ruthenium crystals, a group IVa element compound represented by zirconium oxide or zirconium hydroxide, and a silicon compound represented by silicon oxide or silicon hydroxide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a cycloolefin by hydrogenating a monocyclic aromatic hydrocarbon in the presence of a ruthenium catalyst. Cycloolefins, especially cyclohexenes, are highly valuable as intermediate materials for organic chemical products, especially polyamide raw materials,
It is useful as a lysine raw material.

[0002]

2. Description of the Related Art Various methods are known as methods for producing cycloolefins. Among them, a method of partially hydrogenating a monocyclic aromatic hydrocarbon using a ruthenium catalyst is the most common. Many reports have been made on methods for improving and stabilizing selectivity and yield.

[0003] Among them, in a reaction system in which the yield of cycloolefin is relatively high and water and zinc coexist, for example, a monocyclic aromatic hydrocarbon is subjected to acidic conditions in the presence of water and at least one water-soluble zinc compound. When partially reducing with hydrogen in the liquid phase of the above, the hydrogenation catalyst reduces zinc obtained by previously reducing a ruthenium compound containing a zinc compound to 0.1 to 50 wt.
% Of a metal ruthenium, and using a non-supported catalyst having an average crystallite diameter of the metal ruthenium of 200 ° or less (JP-B-2-16736). Has been proposed.

[0004] Further, as a method for obtaining an industrially stable catalyst system having a high yield of cycloolefins and being industrially stable, the catalyst adheres or deposits on a reactor or another catalyst contact portion, or the like. As an example of adding a metal oxide, metal hydroxide, etc. so that the catalyst does not cause a physical change,
(1) A method in which at least one kind of zirconium oxide or hafnium oxide is added separately from the hydrogenation catalyst, and the reaction is carried out under neutral or acidic conditions in the presence of at least one kind of solid basic zinc sulfate (Japanese Patent Publication No. (3-5371), (2) Apart from the hydrogenation catalyst, except for boron III
Group A element, Group VB element except vanadium, chromium, iron,
A method in which a reaction is carried out by adding at least one metal oxide selected from cobalt, titanium or silicon (Japanese Patent Publication No. 3-35298), (3) a method in which a metal ruthenium having an average crystallite diameter of 200 ° or less is mainly used. Apart from the hydrogenation catalyst particles as components, titanium, niobium, tantalum, chromium,
A method in which at least one metal oxide selected from iron, cobalt, aluminum, gallium and silicon is added, and the reaction is carried out under neutral or acidic conditions in the presence of at least one solid basic zinc (Japanese Patent Publication JP-A-3-7646), (4) When a monocyclic aromatic hydrocarbon is partially reduced with hydrogen in the coexistence of water, a hydrogenation catalyst mainly containing metal ruthenium having an average crystallite diameter of 200 ° or less is used. Separately from the catalyst particles, a hydroxide or hydrate of at least one metal selected from titanium, zirconium, hafnium, niobium, tantalum, chromium, iron, cobalt, aluminum, gallium and silicon. By adding and reacting under neutral or acidic conditions,
A method for producing a cycloolefin that can be used as a stable catalyst system (Japanese Patent Publication No. 8-16073) has been proposed.

[0005]

However, according to the study of the present inventors, when the hydrogenation reaction of a monocyclic aromatic hydrocarbon is carried out continuously and for a long time by these conventionally known methods, It was confirmed that the catalyst activity decreased with time. Moreover, this decrease in catalytic activity
Such physical changes and poisoning of the catalyst are considered to be due to completely different causes, and should be suppressed by a series of methods of adding metal oxides or hydroxides to the catalyst system, which is a known stabilization technique. Proved difficult. In addition, it was observed that the catalytic activity decreasing behavior increased with time under a continuous reaction over a long period of time, and further, it was found that the increasing tendency became remarkable by increasing the reaction temperature. .

In general, in a long-term continuous reaction, the cause of a decrease in the catalytic activity is caused by a decrease in the catalytically active surface due to agglomeration and an increase in the metal crystallite diameter observed in the physical change of the catalyst, Examples thereof include a metal poisoning effect derived from a material such as a contact portion of a reactor and a catalyst. However, regarding the decrease in the present catalytic activity, it is considered that there is a cause different from the conventionally recognized decrease in the catalytic activity because no change in the catalyst suggesting the above-mentioned cause is observed. This decrease in catalyst activity occurs only when the reaction is performed continuously in the coexistence of hydrogen, and the reaction is temporarily stopped as in a batch-type repetitive reaction, or the catalyst slurry is released into the air. When something happens,
In some cases, a decrease in activity cannot be confirmed as if it had been regenerated. Further, the activity lowering behavior changes depending on the reaction temperature, and the phenomenon is extremely unclear, for example, it is difficult to confirm at a low reaction temperature. Therefore, it is considered that the above-mentioned decrease in the catalytic activity could not be confirmed by the known method.

Although the reason for such a decrease in the catalytic activity has not been sufficiently explained, it may be caused by the fact that the reaction is carried out in the coexistence of hydrogen, or that the reaction is observed under a continuous reaction. The present inventor believes that some reaction inhibitory factors caused by the interaction of hydrogen and the ruthenium catalyst are:
It is speculated that it will increase with time under the reaction conditions. When the hydrogenation of a monocyclic aromatic hydrocarbon is industrially carried out by a long-term continuous reaction, this reduction in catalytic activity poses a problem in improving the stability and production efficiency of the reaction system. In addition, since the degree of activity decrease varies depending on the reaction temperature, there is a problem that it is not always possible to select a reaction temperature condition advantageous for the selectivity of cycloolefin. Further, when the activity of the catalyst is reduced, an operation associated with the activity recovery such as a catalyst reprocessing method or a method for recovering the activity of the ruthenium catalyst is required, and there is a problem in terms of simplicity. From these facts, there is a strong demand for an industrially stable catalyst capable of setting advantageous reaction conditions that can provide cycloolefins with high selectivity without the aforementioned decrease in activity.

[0008]

In order to solve the above-mentioned problems, to improve the selectivity of cycloolefin, and to obtain a stable catalyst system which is industrially advantageous, the present inventor has proposed a hydrogen containing metal ruthenium as a main component. The present inventors have made intensive studies on a system composed of activated catalyst particles and other components and arrived at the present invention.

That is, the claims of the present invention are as follows. 1) monocyclic aromatic hydrocarbon in the presence of water and metal sulfate,
In the partial reduction with hydrogen, a catalyst system in which three kinds of components of (1) hydrogenation catalyst particles containing metal ruthenium as a main component, (2) a compound of Group IVA of the periodic table, and (3) a silicon compound are used. A method for producing a cycloolefin, wherein the reaction is carried out under neutral or acidic conditions.

[0010] 2) The process for producing cycloolefin as described in [1] above, wherein the hydrogenation catalyst particles are metal ruthenium obtained by reducing a ruthenium compound. 3) The cycloid described in the above 1 or 2, wherein the hydrogenation catalyst particles are a reduced product of ruthenium preliminarily containing zinc, and the unsupported catalyst has a crystallite diameter of 200 ° or less. Olefin production method.

4) The hydrogenation catalyst particles are zinc-containing ruthenium obtained by reducing a ruthenium compound containing a zinc compound in advance, and have a zinc content of 0.1 to 0.1 with respect to ruthenium as a main component. 4. The method for producing a cycloolefin according to any one of the above items 1 to 3, which is 50% by weight. 5) The compound of Group IVA of the periodic table is an oxide or hydroxide of zirconium, and the amount of the compound is 1 to water.
1 × 10 ^{−3 to} 0.1 times by weight
The method for producing the cycloolefin described above.

6) The silicon compound is silicon oxide or hydroxide, and the amount of the silicon compound is 1 × 10 ^{-5 with} respect to water.
2. The method for producing a cycloolefin according to the above item 1, wherein the amount is from 0.1 to 0.1 times by weight. 7) The silicon compound is an oxide or hydroxide of silicon, and the added amount thereof is 1 × 10 3 based on the amount of zirconium oxide or hydroxide which is a compound of Group IVA of the periodic table.
7. The method for producing a cycloolefin according to the above 1, 5, or 6, wherein the amount is at least ^-2 times by weight.

8) The compound of group IVA of the periodic table is an oxide or hydroxide of zirconium, and the silicon compound is
8. The method for producing a cycloolefin according to the above 1 or 7, which is an oxide or hydroxide of silicon, wherein each element compound is added to the catalyst system and the reaction is carried out in a physically mixed state. 9) The process for producing a cycloolefin according to the above 1, 5 or 6, wherein water is present in an amount of 0.5 to 20 times by weight of the monocyclic aromatic hydrocarbon.

(10) The cyclosulfate as described in any of (1) to (10) above, wherein the metal sulfate is zinc sulfate and water is 1.0 × 10 ^{−4 to} 0.5 times by weight. Olefin production method. Hereinafter, the present invention will be described in detail. The present invention relates to a method for partially reducing a monocyclic aromatic hydrocarbon with hydrogen in the presence of water and a metal sulfate.

In the present invention, the monocyclic aromatic hydrocarbon is
An aromatic hydrocarbon having one benzene ring, for example, benzene, toluene, xylene, and usually 1 carbon atom
Specific examples thereof include benzene substituted with lower alkyl groups of 4 to 4. The hydrogenation catalyst particles of the present invention,
The catalyst particles are mainly composed of ruthenium metal, and the ruthenium catalyst is a catalyst containing ruthenium metal obtained by previously reducing a number of ruthenium compounds. Ruthenium compounds, for example, chloride, bromide, halides such as iodide, or nitrates, sulfates, hydroxides,
Alternatively, various ruthenium-containing complexes such as ruthenium carbonyl complex, ruthenium acetylacetonate complex, ruthenocene complex, ruthenium ammine complex, and
Compounds derived from such complexes can be used. Further, two or more of these ruthenium compounds may be used in combination. As a method for reducing these ruthenium compounds, a catalytic reduction method using hydrogen or carbon monoxide,
Alternatively, a chemical reduction method using formalin, sodium borohydride, hydrazine, or the like may be used in a gas phase or a liquid phase.

Before or after the reduction of the ruthenium compound, other metals or metal compounds such as zinc, chromium, molybdenum, tungsten, manganese, cobalt, nickel, iron, copper, gold, platinum and the like, A compound mainly composed of ruthenium obtained by adding a compound of the above metal may be used. When such a metal or metal compound is used, it is usually selected in the range of 0.001 to 20 as the atomic ratio to the ruthenium atom. Among them, it is preferable to add zinc or a zinc compound before the reduction of the ruthenium compound, and the hydrogenation catalyst particles obtained by the reduction contain 0.1 to 50% by weight of zinc based on ruthenium as the main component. More preferably,

The hydrogenation catalyst particles containing ruthenium metal as a main component are non-supported catalysts in which the average crystallite diameter of the constituent ruthenium metal is preferably 200 ° or less. The average crystallite diameter of the metal ruthenium is calculated from the spread of the diffraction line width obtained by the X-ray diffraction method using the metal ruthenium catalyst by the Scherrer's formula. Specifically, using a CuKα ray as an X-ray source, a diffraction angle (2θ)
Is calculated from the spread of the diffraction line having a maximum around 44 °.

In the present invention, the reaction is carried out in a reaction field in which a compound of the group IVA of the periodic table and a silicon compound coexist in addition to the hydrogenation catalyst particles mainly containing ruthenium metal. The compound of Group IVA of the periodic table in the present invention is an oxide or a hydroxide of titanium, zirconium, or hafnium, and may be used alone or in combination of two or more. You may. Among these, zirconium oxide or hydroxide is particularly preferable, and the amount of zirconium used is 1 × 10 ^{−4 to} 0.3 times by weight, preferably 1 × 10 ^{−3 to} 0.1 times by weight with respect to water. It is. The oxide or hydroxide may be, for example, a dried powder or sol. In the present invention, the type of the form or the like is not particularly limited, and a wide variety of types is used. be able to.

The effects of the present invention obtained by coexisting such oxides or hydroxides in the reaction system are various, and the substantial effectiveness of the present invention is described firstly by improving the selectivity of cycloolefin. The effect can be raised. Among the conventionally known oxides and hydroxides, compounds of Group IVA of the periodic table have an effect of improving the selectivity, and among them, the coexistence effect of the oxide and hydroxide of zirconium is particularly large. Specifically, when their presence hardly affects the activity of the hydrogenation catalyst particles and a monocyclic aromatic hydrocarbon such as benzene is used in the reaction, the selection of cyclohexene in the reaction product is selected. Rate can be improved.

The second effect of the present invention is to suppress the reaction system from fluctuating due to adhesion of the hydrogenation catalyst to the surface of the reactor and agglomeration during the reaction. That is,
By using a zirconium oxide or hydroxide, a physically stable reaction system can be maintained. Normally, when a fine metal catalyst is used, aggregation and sintering progress in the reaction system, unlike when a metal catalyst supported on a carrier is used, and a physically stable catalyst system is maintained. Is extremely difficult. In this regard, the same applies to the metal ruthenium catalyst used in the method of the present invention. Therefore, a technique for avoiding the progress of agglomeration and sintering is a technique that is absolutely necessary in practice. The present inventor has found that the oxide or hydroxide of zirconium according to the present invention functions as a dispersant for preventing aggregation of the metal ruthenium fine particles, and therefore, a decrease in activity due to physical factors of the catalyst is extremely effectively suppressed. I guess.

A third effect of the present invention is that the handling property of the hydrogenation catalyst slurry is remarkably improved as compared with the case where zirconium oxide or hydroxide is not used. For example, when adjusting the concentration of the hydrogenation catalyst or when charging the catalyst, since the catalyst is hard to adhere to the vessel wall or the pipe wall, the workability is improved, or when the catalyst is recovered from the catalyst slurry,
The catalyst has excellent effects such as easy separation of the catalyst from the slurry and extremely easy recovery operation.

It is necessary that a silicon compound coexist in the catalyst system of the present invention. The silicon compound is preferably an oxide or hydroxide of silicon, and the amount of the oxide or hydroxide of silicon is 1 × 10 ^{−6 to} 0.3 times by weight, preferably 1 × 10 ^{−5 with} respect to water. 0.1 times by weight. The oxide or hydroxide may be a sol or a gel. In the present invention, the type of the form or the like is not particularly limited, and a wide variety of types can be used.

The coexistence of a silicon compound, preferably an oxide or hydroxide of silicon, has the same effects as the second and third effects exhibited when a compound of Group IVA of the periodic table is contained. . That is, it has the effect of suppressing the fluctuation of the reaction system due to the attachment or aggregation of the catalyst to the reactor surface, and the function of avoiding the progress of the aggregation and sintering is achieved by the coexistence of the silicon compound. The system is provided with a function as if coexisting with a dispersant, and the reduction in catalytic activity due to the physical factors described above is suppressed. Furthermore, the present inventor has reported that silicon compounds, particularly silicon oxides or hydroxides, decrease the activity of the catalyst which is different from the coexistence effect obtained when other known metal species coexist in the catalyst slurry. For the first time, we have found that it has an inhibitory effect. This effect is a surprising effect obtained only for silicon compounds.

Conventionally, a hydrogenation catalyst containing ruthenium metal as a main component, which is used continuously and for a long time for hydrogenation of a monocyclic aromatic hydrocarbon, is completely different from such a physical change and poisoning of the catalyst. As described above, there is a decrease in the catalytic activity with time, which is considered to be caused by the above. However, a sufficiently effective proposal has not yet been made for the problem of reduction in catalyst activity, and conventional measures have been limited to post-treatments such as a method for regenerating a catalyst with reduced activity and a method for recovering activity. Therefore, the present inventor has repeatedly studied to cope with the above-mentioned decrease in activity by improving the catalyst, and as a result, has found that a silicon compound, preferably an oxide or hydroxide of silicon, can suppress a decrease in catalyst activity. I was sorry. This is a surprising finding and can significantly improve conventional catalyst technology.

In the present invention, as described above, in addition to the hydrogenation catalyst particles containing ruthenium metal as a main component, both a compound of the group IVA of the periodic table and a silicon compound coexist. Periodic Table IV
The group A compound is a compound of titanium, zirconium and hafnium, preferably an oxide or hydroxide thereof, and particularly preferably an oxide or hydroxide of zirconium. The silicon compound is preferably an oxide or hydroxide of silicon. In the present invention, the amount of the silicon oxide or hydroxide is preferably 1 × 10 ⁻² weight times or more the amount of zirconium oxide or hydroxide which is a compound of Group IVA of the periodic table.

If the amount of the oxide or hydroxide of silicon is too small relative to the amount of the oxide or hydroxide of zirconium, the effect of suppressing the activity decrease may not be obtained. Further, it is difficult to improve the reaction selectivity unless a zirconium oxide or hydroxide is present in the catalyst system, and only by allowing both a compound of Group IV of the periodic table and a silicon compound to coexist in the catalyst system. It is possible to obtain a catalyst system having high selectivity and no decrease in activity, and it is possible to obtain an excellent effect which cannot be obtained by simply coexisting only one of them.

When an oxide or hydroxide of zirconium and silicon is used in the present invention, it is more preferable to add the respective element compounds to the catalyst system and carry out the reaction in a physically mixed state. . Both zirconium and silicon added in addition to the hydrogenation catalyst particles containing metal ruthenium as a main component can be used as oxides, in addition to the case where they are used in a physically mixed state as described above, if necessary. Both types may be used in combination. The compounding method is a method of impregnating or immersing other elements in the pores of each other as oxides, a method of adsorbing on the surface using a chemical action, a mixing method or a solution method. It is possible to use a method of spray-drying the catalyst slurry prepared by using the above method. However, the oxides prepared in this manner exhibit a lower effect than when the reaction is carried out in the above physically mixed state.

The constitution and effect of the present invention described above in terms of the two effects of maintaining high selectivity and suppressing the decrease in activity have not been described or suggested in any conventional literature. The present inventor has set forth the relationship between the quantitative ratios of zirconium and silicon described above, with respect to zirconium oxide or hydroxide,
It is presumed that, where the amount of silicon oxide or hydroxide is extremely low, the effect of suppressing the decrease in activity of silicon may be impaired by zirconium.
In addition, regarding the reason why it is more effective to carry out the reaction in a state in which various hydroxides or oxides are physically mixed, respectively, in the catalyst slurry system, the physical, It is thought that the chemical properties can be sufficiently exhibited without being hindered by other entities.

According to the present invention having the functions and effects described in detail above, it is possible to increase the reaction temperature, which is limited by the conventional catalyst system due to the effect of increasing the rate of activity decrease, Selectivity can also be improved. Furthermore, it is not necessary to perform an operation associated with activity recovery such as a catalyst reprocessing method used when the activity of the catalyst is reduced or a method for recovering the activity of a ruthenium catalyst, and to maintain a high yield of cycloolefins for a long period of time. In addition, the catalyst activity can be made stable. That is, the present invention provides a practically excellent method for producing a cycloolefin.

Water is present in the reaction system of the present invention, and its amount varies depending on the type of reaction. However, water may be present in an amount of 0.001 to 100 times by weight based on the monocyclic aromatic hydrocarbon used as the starting material. it can. However, under the reaction conditions, it is necessary that an organic liquid phase mainly composed of the raw material and the product and a liquid phase containing water need to form two phases. When a small amount of water is present, the selectivity of cycloolefin is reduced, and if the amount is too large, there is a problem that the reactor becomes large. 5
It is preferable to allow them to coexist by 20 to 20 times by weight.

The reaction system of the present invention requires the presence of a metal sulfate. It is not necessary that the metal sulfate is present in the reaction system in its entirety as a solid, and it is preferable that the metal sulfate is present in a state where at least a part thereof is dissolved in the aqueous phase existing in the reaction system. Metal sulfates to be present in the reaction system include zinc, iron, nickel, cadmium, gallium, indium, magnesium, aluminum, chromium, manganese,
Cobalt, copper, and the like can be exemplified, and these may be used alone or in combination of two or more. Further, a double salt containing such a metal sulfate may be used. It is particularly preferable to use zinc sulfate as the metal sulfate. The amount of the metal sulfate used is 1.0 × 10 4 of water present in the reaction system.
^{-5 to} 1.0 times by weight, especially when zinc sulfate is used as the metal sulfate, it is more preferably 1.0 × 10 ^{-4 to} 0.5 times by weight.

Further, in the reaction system of the present invention, the following known metal salts may be present. That is, examples of the type of the metal salt include Group IA metals such as lithium, sodium and potassium in the periodic table, Group IIA metals such as magnesium and calcium, or zinc and manganese.
Cobalt, copper, cadmium, lead, arsenic, iron, gallium,
Metal nitrates such as germanium, vanadium, chromium, silver, gold, platinum, nickel, barium and aluminum, chlorides, oxides, hydroxides, acetates, phosphates, etc.
Alternatively, two or more of them may be used by mixing them chemically and / or physically. Among these, the addition of a zinc salt such as zinc hydroxide or zinc oxide is also preferred in the present invention, and particularly a double salt containing zinc hydroxide, for example, a compound of the general formula (Zn
SO ₄ ) _m · (Zn (OH) ₂ ) _n : n = 1:
The presence of a double salt of 0.01 to 100 is particularly preferred.

The catalyst system of the present invention includes a hydrogenation catalyst particle mainly composed of ruthenium metal, a compound of Group IVA of the periodic table,
In addition to the three types of components of the silicon compound, metal sulfates and metal salts are present, and it is necessary to make the aqueous phase of the catalyst system neutral or acidic for the reaction. When the aqueous phase is made alkaline, the reaction rate is remarkably reduced, and it is not practical as a method for producing cycloolefin. In addition, a normal acid, for example, hydrochloric acid, nitric acid, sulfuric acid, acetic acid, phosphoric acid, etc. may be added to make it acidic. The pH of the aqueous solution thus introduced into the reaction system is preferably 0.5 to 7 or less.

As described above, the reaction for producing cycloolefin according to the method of the present invention is usually carried out continuously or batchwise by a liquid phase suspension method, but may be of a fixed bed type. The reaction conditions are appropriately selected depending on the types and amounts of the catalyst and additives used, but the reaction pressure may be 1 to 20 MPa, more preferably 2 to 7 MPa. The reaction temperature may be 50 to 250 ° C, more preferably 100 to 200 ° C.

[0035]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on embodiments, but the present invention is not limited to those embodiments. In the following Examples and Comparative Examples, the selectivity of cyclohexene was calculated by the following formula based on the concentration analysis value of the experiment. Cyclohexene selectivity (%) = (moles of cyclohexene produced by the reaction) × 100 / P where P (moles) = (moles of cyclohexene produced by the reaction) + (moles of cyclohexane produced by the reaction) The conversion rate of benzene was calculated by the following formula based on the analysis value of the benzene concentration. Benzene conversion (%) = (moles of benzene consumed by reaction) × 100 / (moles of benzene supplied to reaction)

[0036]

Examples 1-3 Ruthenium hydride catalyst containing 8.3% by weight of zinc obtained by reducing ruthenium hydroxide containing zinc hydroxide in advance (average crystallite diameter of about 56 °)
8.75 g, the amount of zirconium oxide powder and silica gel are shown in Table 1, the aqueous solution was dissolved ZnSO ₄ · 7H ₂ O (Wako Pure Chemical Industries, Ltd. special grade) 430.94G 232
0 ml was charged into a 4 liter Hastelloy C tank-type flow reactor having an oil / water separation tank as an auxiliary tank and used as a reaction vessel, and was subjected to catalyst poisoning substances such as sulfur at 170 ° C. and 5 MPa under hydrogen pressure. Was continuously supplied at 1.5 L / Hr. At this time, the aqueous phase containing the catalyst in the reaction system was always made to have a constant composition, and the reaction product consisting of benzene, cyclohexene and cyclohexane was continuously taken out from the oil / water separation tank, while the catalyst was removed. The aqueous phase containing the solution was returned to the reactor as a circulation type, and a partial hydrogenation reaction of benzene was continuously performed. The reaction results under these reaction conditions were determined by sampling a part of the oil taken out from the oil / water separation tank and analyzing it by gas chromatography. Table 1 shows the reaction results after 20 hours and 200 hours after the start of the flow reaction.

[0037]

[Table 1]

As shown in Table 1, the reaction results of Examples 1 to 3 according to the present invention were excellent, maintaining an unprecedented high selectivity and showing no decrease in catalytic activity.

[0039]

[Comparative Example 1] 175 g of zirconium oxide, solid content concentration 3
5 g of 0% silica sol (solid SiO _Two1.5g as
And the amount of silica sol based on the amount of zirconium oxide
Other than changing the amount to a small amount, the same as in Examples 1 to 3 under the same conditions
Operation. 20 hours after the start of the distribution reaction
Benzene conversion 50.3%, cyclohexene selectivity 7
It was 7.8%. After that, the reaction was continued, resulting in high selection.
Although the rate is maintained, the activity decreases with time, and 200H
benzene conversion is 32.4% and cyclohexane
The sen selectivity was 83.0%.

[0040]

Comparative Examples 2 to 4 The reaction was carried out by replacing zirconium, titanium, and silicon with the oxides of Examples 1 to 3, and coexisting only one kind of each oxide with the hydrogenation catalyst particles containing metal ruthenium as a main component. did. In each comparative example, the same operation as in Examples 1 to 3 was performed, except that 40 g of the oxide powder was used. In the catalyst system using titanium oxide, the supply amount of benzene was set to 2.5 liter / Hr, and at the same time, the amount of circulation of the aqueous phase containing the catalyst flowing out to the oil / water separation tank to the reactor was increased. The oil-water ratio inside was the same as in other experiments. Table 4 shows the reaction results at 20 hours and 200 hours after the start of the flow reaction.

[0041]

[Table 2]

In this comparative example, a comparison was made with the case where only two kinds of oxides of Examples 1 to 3 were used, in which only one oxide was used as the oxide coexisting in the hydrogenation catalyst particles. As a result, in the case of only one single oxide, a catalyst system which maintains a high selectivity and does not cause a decrease in activity was not found. Further, from this comparative example, zirconium oxide,
If titanium oxide is used, the catalytic activity decreases,
On the other hand, when silicon oxide is used, the activity does not decrease,
The difference in effect depending on the type of oxide was clarified, such that the selectivity was lower than when zirconium oxide or titanium oxide was used.

[0043]

Comparative Examples 5-7 Sols of each oxide were used in place of the oxide powders of Comparative Examples 2-4. The zirconia sol and silica sol used had a solid content of 30%, and the amount of sol added was 8.75 g (2.625 g as a solid oxide).
The other conditions and operations were the same as in Examples 1 to 3. On the other hand, titania sol having a solid concentration of 10.7% is used, and the amount of the catalyst is 5.5 g of hydrogenation catalyst particles containing ruthenium metal as a main component, and the amount of titania sol is 30 g (3.21 g as a solid oxide). The other conditions and operations were the same as in Examples 1 to 3. Table 3 shows the results.

[0044]

[Table 3]

Similar to the results of Comparative Examples 1 to 4, in each case, no catalyst system was found which maintained a high selectivity and did not cause a decrease in activity. In addition, the difference in the effect depending on the type of the oxide was similar to the results of Comparative Examples 2 to 4. From the above results, the effect differs depending on the type of oxide coexisting in the hydrogenation catalyst particles containing ruthenium metal as a main component, the hydrogenation catalyst particles containing metal ruthenium as a main component according to the present invention, a compound of Group IVA of the periodic table, The effectiveness of the catalyst system in which the three components of the silicon compound coexist can be determined. Observation of the apparatus and catalyst slurry after completion of the reaction in each example showed no adhesion of the hydrogenation catalyst or agglomeration of the hydrogenation catalyst on the reactor surface. Was maintained.

[0046]

According to the present invention, in a continuous hydrogenation reaction of a monocyclic aromatic hydrocarbon, the desired cycloolefin can be stably produced at a high selectivity for a long time without a decrease in activity. It becomes possible. Furthermore, the present invention does not require an operation associated with activity recovery, such as a method for reprocessing a catalyst whose activity has decreased, and is industrially extremely valuable as it can efficiently produce cycloolefins as compared with conventional catalyst systems. .

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[Procedure amendment]

[Submission date] November 2, 1998 (1998.11.
2)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0040

[Correction method] Change

[Correction contents]

[0040]

Comparative Examples 2 to 4 The reaction was carried out by replacing zirconium, titanium, and silicon with the oxides of Examples 1 to 3, and coexisting only one kind of each oxide with the hydrogenation catalyst particles containing metal ruthenium as a main component. did. In each comparative example, the same operation as in Examples 1 to 3 was performed, except that 40 g of the oxide powder was used. In the catalyst system using titanium oxide, the supply amount of benzene was set to 2.5 liter / Hr, and at the same time, the amount of circulation of the aqueous phase containing the catalyst flowing out to the oil / water separation tank to the reactor was increased. The oil-water ratio inside was the same as in other experiments. Table 2 shows the reaction results at 20 hours and 200 hours after the start of the flow reaction.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0041

[Correction method] Change

[Correction contents]

[0041]

[Table 2]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0044

[Correction method] Change

[Correction contents]

[0044]

[Table 3]

Claims (10)

[Claims] 1. A method for partially reducing a monocyclic aromatic hydrocarbon with hydrogen in the presence of water and a metal sulfate, comprising: (1) a hydrogenation catalyst particle mainly composed of ruthenium metal; and (2) a group IVA of the periodic table. A method for producing a cycloolefin, comprising reacting a catalyst system in which three kinds of components of the compound (3) and (3) a silicon compound coexist under neutral or acidic conditions. 2. The method for producing cycloolefin according to claim 1, wherein the hydrogenation catalyst particles are metal ruthenium obtained by reducing a ruthenium compound. 3. The method according to claim 1, wherein the hydrogenation catalyst particles are a reduced product of ruthenium preliminarily containing zinc, and the unsupported catalyst has a crystallite diameter of 200 ° or less. 3. The method for producing a cycloolefin according to 2. 4. The hydrogenation catalyst particle is a zinc-containing ruthenium obtained by reducing a ruthenium compound containing a zinc compound in advance, and has a zinc content of 0.1 to 0.1 with respect to ruthenium as a main component. 50% by weight
The method for producing a cycloolefin according to any one of claims 1 to 3, wherein 5. The compound of Group IVA of the Periodic Table is an oxide or hydroxide of zirconium, the amount of which is 1 × 10 ^{−3 to} 0.1 times the weight of water. The method for producing a cycloolefin according to claim 1. 6. The silicon compound is an oxide or hydroxide of silicon, and the addition amount thereof is 1 × 10 ⁻⁵ to water.
The method for producing a cycloolefin according to claim 1, wherein the amount is 0.1 times by weight. 7. The silicon compound is an oxide or hydroxide of silicon, and the added amount thereof is 1 × 10 ^{−2 with} respect to the amount of zirconium oxide or hydroxide which is a compound of Group IVA of the periodic table. 7. The method for producing a cycloolefin according to claim 1, wherein the weight is at least twice the weight. 8. The compound of Group IVA of the Periodic Table is an oxide or hydroxide of zirconium, and the silicon compound is an oxide or hydroxide of silicon. The method according to claim 1 or 7, wherein the reaction is carried out in a physically mixed state. 9. The method according to claim 9, wherein the water is 0.5 to 2 monocyclic aromatic hydrocarbons.
7. The method for producing a cycloolefin according to claim 1, wherein the cycloolefin is present in an amount of 0 times by weight. 10. The method according to claim 1, wherein the metal sulfate is zinc sulfate and is 1.0 × 10 ^{−4 to} 0.5 times by weight of water. Method for producing cycloolefin.