JPH09110733A - Production of cycloolefin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To more effectively produce a cycloolefin by partial hydrogenation reaction of a monocyclic aromatic hydrocarbon. SOLUTION: A monocyclic aromatic hydrocarbon is partially hydrogenated in the presence of a catalyst and water to produce a cycloolefin. In this time, a ruthenium-containing ternary-based catalyst containing (1) ruthenium, (2) at least one kind selected from a group comprising manganese, iron, cobalt, nickel and zinc and (3) at least one kind selected from a group comprising gold, silver and copper and obtained by preparing a catalyst precursor containing ruthenium component, carrying out oxidation treatment or heating treatment of the catalyst precursor and then carrying out reduction treatment of the treated precursor is used as the catalyst.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a process for producing a cyclohexene by partially hydrogenating a monocyclic aromatic hydrocarbon and correspondingly hydrogenating a corresponding cycloolefin, in particular, benzene. Cycloolefins, lactams, polyamide raw materials such as dicarboxylic acid, lysine, pharmaceuticals,
It is a compound useful as an important intermediate material such as pesticides.

[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. As the ruthenium catalyst, a method of using fine particles of metal ruthenium as it is (JP-A-61-61
-50930, JP-A-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-53-63350, JP-A-57-130926, JP-A-61-61). 40226, JP-A-4-74141, etc.) have been proposed. In general, in the above reaction, the higher the reaction activity of the catalyst, the lower the selectivity of the obtained cycloolefin, so in such a reaction system, zinc sulfate, in the presence of a metal salt such as cobalt sulfate, It is said that a method of suppressing the reaction activity while maintaining high selectivity and yield of the corresponding cycloolefin is preferable.

It is also known that gold, silver, copper, iron, cobalt, manganese, etc. are used in combination with ruthenium in order to increase the selectivity of cycloolefin (JP-A-53-53).
63350, and JP-A-4-74141). In particular, JP-A-61-2232 and 61-12232 describe an example in which barium sulfate is used as a carrier and three kinds of metals, ruthenium-iron or cobalt-copper or silver, are used as a catalyst component.

[0005]

However, all the conventional methods have some problems, and an industrially advantageous method is not always established. In particular, the target cycloolefin selectivity is still insufficient.

[0006]

[Means for Solving the Problems] In order to solve the above problems, the present inventors have made a detailed study on the production process of a ruthenium catalyst to be used particularly when carrying out a partial hydrogenation reaction of a monocyclic aromatic hydrocarbon. As a result, it was found that the reaction results with the ruthenium catalyst obtained by adopting a specific production process are remarkably improved, and the present invention was accomplished.

That is, the gist of the present invention is to prepare a catalyst precursor containing a ruthenium component when partially hydrogenating a monocyclic aromatic hydrocarbon in the presence of a catalyst and water to produce a cycloolefin, (1) Ruthenium, which is obtained by subjecting a catalyst precursor to oxidation treatment or heat treatment, and then reduction treatment
(2) at least one selected from the group consisting of manganese, iron, cobalt, nickel and zinc, and (3) gold,
A method for producing a cycloolefin, which comprises using a ruthenium-containing ternary catalyst containing at least one selected from the group consisting of silver and copper.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. The catalyst used in the present invention is selected from the group consisting of (1) ruthenium, (2) manganese, iron, cobalt, nickel and zinc, and (3) gold, silver and copper. A ruthenium-containing ternary catalyst containing at least one kind. In the partial hydrogenation reaction of a monocyclic aromatic hydrocarbon, ruthenium as the first component alone has some catalytic activity, but in the present invention, it is necessary to use it in combination with the above second and third components. To do. Of the second component manganese, iron, cobalt, nickel and zinc, cobalt and zinc are preferable. The second component is used in an atomic ratio to ruthenium of usually 0.01 to 20, preferably 0.05 to 10.

The third component gold, silver and copper belong to Group 11 elements, preferably gold and copper. The third component has an atomic ratio to ruthenium of usually 0.01 to 2
It is used in the range of 0, preferably 0.05 to 10. Furthermore, as a preferable combination of the catalyst components consisting of three groups, ruthenium-zinc-gold, ruthenium-zinc-copper,
Examples thereof include a ruthenium-cobalt-copper system.

Examples of the raw material for ruthenium which is a catalytically active component include halides, nitrates and hydroxides of ruthenium, complex compounds such as ruthenium carbonyl and ruthenium ammine complexes, and ruthenium alkoxides. Among them, ruthenium chloride is preferably used. As the raw materials for the second and third catalyst components other than ruthenium, halides, nitrates, acetates, sulfates of each metal and complex compounds containing each metal are used.

In the present invention, the step of preparing a catalyst precursor containing a ruthenium component is a step exemplified by the alkali precipitation method in the case of a non-supported catalyst, and a step of a carrier-supported catalyst precursor in the case of a carrier-supported catalyst precursor. This is a step of supporting the ruthenium component raw material compound on the catalyst carrier. By subjecting this catalyst precursor to a reduction treatment, the ruthenium component can be reduced and metallized before use as a catalyst.

As a method for preparing the unsupported catalyst precursor,
It may be obtained as a solid by a general coprecipitation method such as an alkali precipitation method using a mixed solution of ruthenium and a compound of a desired cocatalyst metal component, or as a dry product by evaporation in a homogeneous solution state. Good. Although a non-supported type catalyst can be used as the catalyst, in general, a carrier-supported catalyst is preferable because the activity per catalyst component can be improved or the stability of the catalyst activity can be improved. A method for preparing a carrier-supported catalyst precursor, that is, a method for supporting a catalyst component on a carrier, includes immersing the carrier in a catalyst component liquid and then evaporating and drying the solvent to evaporate the solvent to immobilize the active ingredient, A known impregnation-supporting method such as a spray method of spraying the catalytically active component liquid while keeping the carrier in a dry state, or a method of immersing the carrier in the catalytically active component liquid and then filtering it is used.
The second and third catalyst components may be loaded simultaneously with the ruthenium compound, may be loaded in advance and then loaded with ruthenium, or may be loaded in advance with ruthenium and then loaded. As the solvent used for supporting the active ingredient at the time of catalyst preparation, water or an organic solvent such as alcohol, acetone, tetrahydrofuran, hexane or toluene is used. The supported amounts of ruthenium and the second and third catalyst components are usually 0.001 to 10% by weight, preferably 0.1 to 10% by weight.
5% by weight.

As the carrier used in the above carrier-supported catalyst body, silica, alumina, silica-alumina, zeolite, activated carbon, or general metal oxides, complex oxides, hydroxides, sparingly water-soluble metal salts are used. Etc. are illustrated. As the carrier, a poorly soluble oxide or metal salt generally used as a catalyst carrier is used. Specifically, barium sulfate, metal salts such as calcium sulfate, silica, alumina,
Zirconia, titania, chromina, oxides of rare earth metals, or composite oxides such as silica-alumina, silica-zirconia, zirconium silicate,
Examples thereof include silica modified with a metal oxide such as zirconia.

Among the above carriers, carriers having the following properties can be preferably used. When the pore volume and the pore distribution are measured by the mercury intrusion method, the pore diameter is 75 to 100,00.
The total pore volume of 0Å is 0.2 to 10 ml / g, preferably 0.3 to 5 ml / g, and the pore diameter is 75 to 1
With respect to the total pore volume of 0,000Å, the volume of pores having a diameter of 250 Å or more is usually 50% or more, preferably 70% or more.
% Of the carrier. Pore diameter is 250Å
If the ratio of the pores of less than 1 is too large, the selectivity tends to decrease, which is not preferable.

Of the above carriers, the oxide carrier is usually preferred, and silica or a carrier obtained by modifying the silica carrier with a transition metal compound, particularly a carrier obtained by modifying zirconia into silica is exemplified. . In this zirconia-modified silica carrier, the amount of zirconia that modifies the silica matrix is usually 0.1 to 20% by weight, preferably 0.5 to 10% by weight, based on the silica. As a method for preparing a silica carrier modified with zirconia, a solution in which a zirconium compound is dissolved in water or an organic solvent,
Alternatively, after dissolving the zirconium compound, using a solution obtained by partially or entirely hydrolyzing with an alkali or the like, supporting the silica on a silica by suitably using a known impregnation supporting method or a dip coating method, and then drying and firing. A method is used. Examples of the zirconium compound used here include zirconium halides, oxyhalides, nitrates, oxynitrates, hydroxides, complex compounds such as zirconium acetylacetonate complexes, zirconium alkoxides, and the like. The firing temperature here may be any temperature that is higher than the temperature at which the used zirconium compound becomes zirconia, and is usually 600 ° C. or higher, and 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.

The second and third catalyst components other than ruthenium do not always need to be contained in the catalyst precursor, and may be added at any stage after the above-mentioned catalyst precursor preparation step. Good. For example, there is a method in which a catalyst precursor containing a ruthenium component, which will be described in detail below, is subjected to oxidation treatment, heat treatment, or reduction treatment, and then impregnated with an aqueous solution of the raw material compounds of the second and third catalyst components. Also,
In this method, it is desirable to impregnate the second and third catalyst components and then carry out a reduction treatment again before use as a catalyst.

Next, an important feature of the present invention is that the catalyst precursor prepared as described above is subjected to an oxidation treatment or a heat treatment and then a reduction treatment. The oxidation treatment method may be a general method, for example, a method of contacting an oxygen-containing gas with a catalyst precursor or a method of contacting with an oxidizing agent such as hydrogen peroxide. On the other hand, the heat treatment is usually 80 to 800 ° C., preferably 300 to 600.
C, usually 0.1 to 50 hours, preferably 0.5 to 10
The catalyst precursor is retained for about the time. The heat treatment is distinguished from the subsequent reduction treatment, and thus is performed in an oxidizing gas atmosphere or an inert gas atmosphere.

When the catalytic oxidation with oxygen gas is carried out under heating, that is, in an oxygen-containing gas atmosphere, it is usually 8
In the case of calcination at 0 to 800 ° C., preferably 300 to 600 ° C., the above-mentioned oxidation treatment and heat treatment of the catalyst precursor are carried out at the same time, which is one of the preferred embodiments of the present invention. The reason why the selectivity of cycloolefin is improved by using the catalyst prepared by subjecting the catalyst precursor to oxidation treatment or heat treatment is not clear, but in the case of passing through the treatment, in the subsequent reduction treatment step. Producing an active site advantageous for forming a metal ruthenium crystal, or the existing form of ruthenium and a co-catalyst component produces an advantageous active site for forming a metal ruthenium crystal in a subsequent reduction treatment. It is estimated that

Next, as the method of the reduction treatment following the oxidation treatment or the heat treatment, a catalytic reduction method using hydrogen gas or a chemical reduction method using formalin, sodium borohydride, hydrazine or the like is used. Of these, catalytic reduction with hydrogen gas is preferable, and usually 80 to 500 ° C., preferably 100 to 450 ° C. in a hydrogen-containing gas atmosphere.
It is fired under the conditions of and reduced and activated. Reduction temperature is 80 ℃
If less than, the reduction rate of ruthenium is significantly reduced,
If it exceeds 500 ° C, agglomeration of ruthenium is likely to occur, which causes a decrease in cycloolefin production yield and selectivity.

In the present invention, the catalyst obtained by the method described above is usually used as a catalyst. By subjecting such a catalyst to the water treatment described below, a catalyst having improved cycloolefin selectivity can be obtained. It is possible to obtain. The water treatment is carried out, for example, by immersing the catalyst (ruthenium reduced product) in water usually 0.01 to 100 times, preferably 0.1 to 10 times the weight of the above catalyst (ruthenium reduced product). The processing conditions are usually from room temperature to 250 ° C., preferably from room temperature to 200 ° C., under normal pressure to pressurization, usually at 10 ° C.
For at least one minute, preferably for 1 to 20 hours. The catalyst treatment atmosphere is usually an inert gas atmosphere or a hydrogen gas atmosphere, preferably a hydrogen gas atmosphere. Furthermore, the catalyst after the water contact treatment is usually dried, and then subjected to a re-reduction treatment, in particular, a contact treatment under a hydrogen gas atmosphere.
It becomes possible to obtain a catalyst with higher activity.

The water used for the above contact treatment may be pure water or an aqueous solution containing a metal salt. At least a part of the metal component in the aqueous metal salt solution binds to the catalyst, so that it functions as a co-catalyst component, and further improvement in catalytic activity can be expected, which is desirable. The types of metal salts include Group 1 metals such as lithium, sodium and potassium, Group 2 metals such as magnesium and calcium, or nitrates, chlorides, sulfates, acetates of metals such as zinc, iron, manganese, and cobalt. Examples thereof include phosphates. The concentration of the metal salt in the aqueous solution is usually 1 × 10 ⁻⁵ to 1 times the weight of water, preferably 1 × 1.
It is 0 ^{−4 to} 0.2 times by weight. The catalyst after the contact treatment is usually used after filtering a metal salt aqueous solution, washing with pure water, and drying. Further, after drying, it is desirable to perform re-reduction treatment under a hydrogen gas atmosphere or the like. The catalyst in the present invention is effective for water treatment as described above, but the type of cocatalyst metal component,
It is necessary to optimize the water treatment conditions depending on the amount or the case where a carrier is used.

The reason why the catalyst exhibits high selectivity of cycloolefin by water treatment is not clear, but for example,
It is considered that by preparing a catalyst precursor containing a ruthenium component, subjecting the catalyst precursor to an oxidation treatment, and then a reduction treatment, a metal ruthenium crystal suitable for the reaction is already formed on the catalyst surface. At the same time, it is presumed that there is an active site having a very strong hydrogenation ability on the surface of the metal ruthenium, which causes an unfavorable reaction (formation of cycloalkanes). It is considered that the cycloolefin selectivity is increased as a result of the effective modification by the treatment to suppress the hydrogenation ability.

The present invention is characterized by using the above ruthenium catalyst. When the present invention is carried out, the reaction starting monocyclic aromatic hydrocarbons are benzene, toluene,
Xylene and lower alkyl group-substituted benzenes having about 1 to 4 carbon atoms are exemplified. Further, the reaction system of the present invention requires the presence of water and a metal salt. Although the amount of water varies depending on the reaction mode, it is generally 0.01 to 10 times by weight, preferably 0.1 to 5 times by weight of the monocyclic aromatic hydrocarbon. In such a range, two phases, that is, an organic liquid phase (oil phase) containing raw materials and products as main components and a liquid phase containing water (aqueous phase) are usually formed. When the ratio between the oil phase and the aqueous phase is extreme, it is difficult to form two phases, and liquid separation is difficult. Further, if the amount of water is too small or too large, the effect of the presence of water is reduced, and if the amount of water is too large, it is necessary to enlarge the reactor, which is not preferable.

Further, it is preferable that a metal salt is present in the reaction system of the present invention. Examples of the metal salt include Group 1 metals such as lithium, sodium and potassium, Group 2 metals such as magnesium and calcium, and nitrates, chlorides and sulfates of metals such as zinc, manganese and cobalt.
Examples thereof include acetates and phosphates, and it is particularly preferable to use cobalt sulfate or zinc sulfate. The amount of the metal salt used is usually 1 × 10 ⁻⁵ to 1 times the weight of water in the reaction system,
It is preferably 1 × 10 ^{−4 to} 0.1 times by weight.

As the reaction conditions of the present invention, the reaction temperature is
It is usually selected from the range of 50 to 250 ° C, preferably 100 to 220 ° C. If the temperature is 250 ° C or higher, the cycloolefin selectivity is lowered, and if it is 50 ° C or lower, the reaction rate is remarkably lowered, which is not preferable. The pressure of hydrogen during the reaction is usually 0.1 to 20 MPa, preferably 0.5 to 10 MPa.
It is selected from the range of MPa. If it exceeds 20 MPa, it is industrially disadvantageous. On the other hand, if it is less than 0.1 MPa, the reaction rate is remarkably reduced, which 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.

[0026]

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.

[0027]

(Equation 1)

[0028]

(Equation 2)

Example 1 (Production of carrier) Zirconium oxynitrate dihydrate 0.8
Silica (Fuji Silysia Chemical Ltd., trade name: CARIACT50) was added to an aqueous solution prepared by dissolving 7 g in 20 ml of pure water.
After adding 8.0 g and immersing at room temperature, water was distilled off and it was made to dry. Next, it was calcined at 1000 ° C. for 4 hours under air flow to prepare a silica carrier modified with 5% by weight of zirconia with respect to silica. The total pore volume of the carrier thus obtained having a pore diameter of 75 to 100,000Å is 0.75 ml.
/ G. Of these, the ratio of the volume of pores having a pore diameter of 250 Å or more was 96%.

(Preparation of Catalyst Precursor) The above-mentioned zirconia-modified silica carrier was added to an aqueous solution containing a predetermined amount of ruthenium chloride, zinc chloride and copper nitrate, and after dipping at 60 ° C. for 1 hour, water was distilled off , A catalyst precursor in which a ruthenium (Ru) component, a zinc (Zn) component, and a copper (Cu) component are respectively loaded on a carrier in an amount of 0.5% by weight, 0.5% by weight, and 0.1% by weight, respectively, by drying. Got the body (Oxidation treatment (heat treatment)) The above catalyst precursor was calcined in an air stream at 500 ° C for 2 hours. (Reduction Treatment) A catalyst was obtained by calcining the catalyst precursor treated above in a hydrogen stream at 200 ° C. for 3 hours.

(Benzene partial hydrogenation reaction) Next, a titanium autoclave having an internal volume of 500 ml was charged with 0.1 ml of a 0.1% cobalt sulfate aqueous solution, 2.0 g of the above catalyst, and 100 ml of benzene. Reaction temperature 150 ° C, pressure 50M
Under the condition of Pa, hydrogen gas was supplied at a flow rate of 57 Nl / Hr and stirred at 1000 rpm to carry out a partial hydrogenation reaction of benzene. The reaction solution was appropriately withdrawn through a nozzle installed in the reactor over time, and the oil phase was analyzed by gas chromatography. The reaction results are shown in Table 1. Although the benzene conversion rate increases with time, the target cyclohexene selectivity tends to decrease.

Comparative Example 1 A catalyst obtained by the same operation as in Example 1 was used except that the oxidation treatment step was omitted in the catalyst preparation step of Example 1,
The partial hydrogenation reaction of benzene was carried out under the same conditions as in Example 1. The reaction results are shown in Table 1. Comparing with Example 1 at the same degree of benzene conversion, it can be seen that the selectivity of cyclohexene is lower than that of Example 1.

[0033]

[Table 1]

Example 2 In an autoclave made of titanium having an internal volume of 500 ml, 10 g of the catalyst obtained by the method of Example 1 and 200% aqueous solution of 6% zinc sulfate were used.
ml. Hydrogen gas was supplied at a flow rate of 57 Nl / Hr under the conditions of a temperature of 200 ° C. and a pressure of 50 MPa.
After stirring at rpm, the catalyst was treated with water for 5 hours. After the treatment, the catalyst was taken out and washed with pure water. Wash catalyst 3
Pure water was added in an amount of 0 times and thoroughly mixed by stirring for 1 hour, etc. until the zinc concentration in the wash water at the time of substantially equilibrium became 0.1 ppm or less. Next, this catalyst was activated by baking in a hydrogen stream at 200 ° C. for 3 hours. Catalyst 2 which has undergone the above water treatment and activation treatment
A partial hydrogenation reaction of benzene was carried out under the same conditions as in Example 1 except that g was used. The reaction results are shown in Table-2.

Example 3 Partial hydrogen of benzene was prepared under the same conditions as in Example 2 except that 2 g of the catalyst obtained in the same manner as in Example 2 was used except that the oxidation treatment temperature in the catalyst preparation step was 400 ° C. The chemical reaction was carried out. The reaction results are shown in Table-2.

[0036]

[Table 2]

[0037]

According to the present invention, in the partial hydrogenation of monocyclic aromatic hydrocarbons, the activity of the catalyst is high and cycloolefins can be obtained with high selectivity.

Claims (11)

[Claims] 1. When producing a cycloolefin by partially hydrogenating a monocyclic aromatic hydrocarbon in the presence of a catalyst and water,
(1) ruthenium, (2) manganese, iron, cobalt, nickel and zinc, which are prepared by preparing a catalyst precursor containing a ruthenium component, subjecting the catalyst precursor to an oxidation treatment, and then subjecting it to a reduction treatment. A method for producing a cycloolefin, which comprises using a ruthenium-containing ternary catalyst containing at least one and (3) at least one selected from the group consisting of gold, silver and copper. 2. When producing a cycloolefin by partially hydrogenating a monocyclic aromatic hydrocarbon in the presence of a catalyst and water,
(1) ruthenium, (2) manganese, iron, cobalt, nickel and zinc, which is prepared by preparing a catalyst precursor containing a ruthenium component, heat-treating the catalyst precursor, and then subjecting it to a reduction treatment. A method for producing a cycloolefin, which comprises using a ruthenium-containing ternary catalyst containing at least one and (3) at least one selected from the group consisting of gold, silver and copper. 3. The method according to claim 1 or 2, characterized in that a catalyst obtained by further treating with water after the reduction treatment is used. 4. The method according to claim 3, wherein the water treatment is performed using an aqueous solution containing a metal salt. 5. The method according to claim 3, wherein a re-reduction treatment is performed after the water treatment. 6. The method according to claim 1, wherein the oxidation treatment or the heat treatment is performed by firing in an oxygen-containing gas atmosphere. 7. The method according to claim 1, wherein the reduction treatment or the re-reduction treatment is performed by firing in a hydrogen-containing gas atmosphere. 8. The method according to claim 1, wherein a catalyst precursor having a ruthenium component supported on a carrier is prepared. 9. The catalyst precursor contains at least one selected from the group consisting of manganese, iron, cobalt, nickel and zinc, and / or at least one selected from the group consisting of gold, silver and copper. The method according to any one of claims 1 to 8, characterized in that 10. Use of a carrier having a total pore volume of 0.2 to 10 ml / g with a pore diameter of 75 to 100,000Å and a pore volume of 50% or more with a pore diameter of 250 Å or more. 10. The method of claim 9, comprising: 11. The method according to claim 1, wherein the monocyclic aromatic hydrocarbon is partially hydrogenated in the presence of water containing a metal salt.