JPS6185334A - Production of cycloolefin - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as an intermediate raw material for lysine, drugs, agricultural chemicals, etc. in high yield, by using a specific aliphatic polyhydric alcohol as an addition agent, and hydrogenating partially an aromatic hydjrocarbon compound in the presence of a ruthenium-silica catalyst and water. CONSTITUTION:In preparing a corresponding cycloolefin (e.g., cyclohexene, etc.) by hydrogenating partially an aromatic hydrocarbon such as benzene, toluene, etc. with hydrogen in the presence of a ruthenium-silica catalyst obtained by hydrolyzing a uniform solution of a ruthenium alkoxide and an alkylsilicate, followed by activation treatment, water, and an addition agent, preferably 10<-3>-0.2mol, especially about 10<-3>-0.1mol based on 0.1g catalyst of 2-6C aliphatic polyhydric alcohol (e.g., ethylene glycol, glycerin, pentaerythritol, etc.) is used as the addition agent. EFFECT:Reaction operations are simple and this process is industrially advantageous.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for producing the corresponding cycloolefins by partial hydrogenation of aromatic hydrocarbon compounds.

Cycloolefins are important intermediate raw materials for lysine, caprolactam, adipic acid, pharmaceuticals, pesticides, dyes, etc.
It is a useful compound. Conventionally, methods for producing cycloolefins include dehydration reaction of cyclohexanols, dehydrohalogenation reaction of halogenated cyclohexanes, cranking reaction of cyclohexylarenes, dehydrogenation reaction of cyclohexanes, or oxidative dehydrogenation of cycloolefins. It is well known that the production of cycloolefins is difficult to carry out because the resulting cycloolefins are usually more easily reduced than the raw aromatic hydrocarbon compounds.

However, since the starting material for both methods is an aromatic hydrocarbon compound, if cycloolefins can be obtained in good yield through the partial hydrogenation reaction of aromatic hydrocarbon compounds, it is possible to obtain cycloolefins using the simplest reaction process. It is also preferred from an industrial point of view.

The following methods are known as methods for producing cycloolefins by partial hydrogenation of aromatic compounds.

(1) in the presence of a catalyst consisting of water and an alkaline agent and at least one reduced cation of a group II element;
How to partially hydrogenate.

(Japanese Patent Publication No. 56-22850) (2) A method of partially hydrogenating a metal oxide such as silica or alumina in the presence of a catalyst mainly supporting ruthenium, water and cobalt sulfate.

(3) A method of partially hydrogenating a solid catalyst containing at least one of ruthenium and rhodium as a main component in the presence of water and a catalyst that has been previously treated with an aqueous solution containing a cationic salt.

Although method (1) has a relatively good yield of cyclohexene, it not only requires an extremely complicated reaction system, but also has problems such as separation of reaction products and corrosion of the reaction apparatus by chlorine ions. Furthermore, it is desired that methods (2) and (3) dramatically improve selectivity and yield. Therefore, it has been difficult to commercially put these methods to practical use.

Recently, the Chemical Society of Japan, 47th Spring Annual Meeting, 4DO2 (198
3) and Chemical Society of Japan, 49th Spring Annual Meeting, 3P13 (
(1984) reported a method in which a homogeneous solution of ruthenium glycoxide and ethyl silicate is hydrolyzed and then partially hydrogenated using a ruthenium-silica catalyst that is activated with hydrogen. The catalyst was published in the 49th Catalyst Symposium (Catalyst Symposium on Catalyst Preparation), A8 (1982),
Oyohi J, C1S, Faraday Trans;
179.127 (1983) etc., but when used as a catalyst for the partial hydrogenation reaction of aromatic hydrocarbon compounds, metal ruthenium is dispersed on the surface of ordinary silica. It was revealed that the cycloolefin yield was dramatically improved compared to supported metal catalysts.

Compared to methods (1) and (2) above, this method does not require the addition of a third component to the reaction system, and compared to method (3) above, the cycloolefin yield is improved. This is a unique reaction system not found in conventional technology.

However, even in this method, the cycloolefin yield never exceeded 30%, making it difficult to put it into practical use industrially.

An object of the present invention is to improve the drawbacks of these conventional techniques and to provide an industrially advantageous method for producing cycloolefins. In order to achieve this object, the present inventors conducted extensive studies and discovered a novel catalyst system suitable for partially hydrogenating aromatic hydrocarbons to produce corresponding cycloolefins, resulting in the present invention.

That is, in the present invention, aromatic hydrocarbons are partially hydrogenated with hydrogen in the presence of a ruthenium-silica catalyst produced by hydrolyzing a homogeneous solution of ruthenium alkoxide and alkyl silicate and then performing an activation treatment, water, and additives. This is a method for producing a cycloolefin, characterized in that an aliphatic polyhydric alcohol having 2 to 6 carbon atoms is used as the additive in the method for producing a corresponding cycloolefin.

The method of the present invention will be explained in more detail.

Aromatic hydrocarbons targeted by the present invention are benzene, toluene, xylene and lower alkylbenzenes. The purity of the aromatic hydrocarbon does not need to be particularly high, and there is no problem even if cycloparaffin, lower paraffinic hydrocarbon, etc. are contained.

The catalyst used in the present invention is the 49th Catalyst Symposium (Catalyst Symposium on Catalyst Preparation), A8 (1982).
, and J., C.S., Faraday Tran.
s.

It is produced by a catalyst preparation method using a well-known alkoxide, such as in 2, U., 127 (1983).

That is, it is prepared by hydrolyzing a homogeneous mixed solution of ruthenium alkoxide and alkyl silicate prepared in advance by reacting ruthenium trichloride and an alcohol, and then drying the solution. As the alcohols used in the reaction with ruthenium trichloride, dihydric alcohols give particularly favorable results. Specific example compounds include ethylene glycol, propanediol, butanediol,
Examples include bentanediol, dimethylpropanediol, and hexanediol. Among these, ethylene glycol gives particularly favorable results. Examples of the alkyl silicate used include methyl silicate, ethyl silicate, propyl silicate, n-butyl silicate, and the like. Among these, ethyl silicate is particularly preferred.

The reaction between ruthenium trichloride and alcohols takes place at a temperature of 50 to 1
It is carried out at 50°C, preferably in the range of 70-100'C. The amount of alkyl silicate added to ruthenium alkoxide is selected in a molar ratio of 1:5 to 1:1500, preferably 1:15 to 1:350.

When the amount of alkyl silicate used is 1:1500 or more, the reaction rate decreases and is uneconomical from an industrial standpoint;
Moreover, when the ratio is less than 1:5, the selectivity of cycloolefin decreases.

The amount of water used for hydrolysis is not particularly limited, but is usually in a volume ratio of 1:0.5 to alkyl silicate.
A range of 5 is preferably used.

The catalyst prepared by the above method is activated by reduction with hydrogen before use. The reduction temperature is selected from the range of 300 to 500°C, preferably 350 to 450°C. If the reduction temperature is below 300°C, the reduction rate of ruthenium will decrease, and if it is above 500°C, the metal surface area will decrease due to agglomeration of ruthenium and the catalyst surface will be modified, causing a decrease in the activity and selectivity of cycloolefin production. .

As the additive which is a feature of the present invention, an aliphatic polyhydric alcohol having 2 to 6 carbon atoms is used.

Examples of aliphatic polyhydric alcohols having 2 to 6 carbon atoms include ethylene glycol, glycerin, propanediol, erythritol, butanediol, arabitol, adonitol, pentaerythritol, bentanediol, dimethylpropanediol, sorbitol, mannitol,
Compounds such as galactitol, hexanediol, methylbentanediol, dimethylbutanediol are preferred. The amount of aliphatic polyhydric alcohol to be used is 0.1
10-3 to 0.2 mol, preferably 10 to 0.2 mol per g
It is 0.1 mole.

In the method of the present invention, water is added into the reaction system. Since the catalyst is suspended in water, not only is the reaction product in the organic layer easily separated from the catalyst, but water has a significant effect on increasing the selectivity to cycloolefins. The amount of water added is usually 0.01 to 10 in volume ratio to aromatic hydrocarbon.
times, preferably from the range of 0.1 to 5 times.

The hydrogen pressure during the reaction is usually selected from the range of 0.1 to 2QMPa, preferably 0.5 to 1QMPa.

A high pressure of 2QMPa or more is uneconomical from an industrial standpoint, and a Q of 1MPa or less is uneconomical in terms of equipment because the reaction rate decreases. The reaction temperature is usually selected from the range of 50 to 250°C, preferably 100 to 200°C. 250
℃ or higher, the selectivity of cycloolefin decreases;
At temperatures below 0°C, the reaction rate is slow, which is disadvantageous.

The reaction format of the present invention is not particularly limited, and can be carried out batchwise or continuously using one or more reaction tanks.

According to the method of the present invention, cycloolefins can be obtained in high yield, and the reaction operation is simple, making it possible to produce cycloolefins industrially advantageously.

In order to explain the present invention more clearly, Examples and Comparative Examples are described below, but the present invention is not limited only by these Examples.

In addition, the conversion rate, yield, and selectivity shown in an Example and a comparative example are defined by the following formula.

Example 1 Ruthenium trichloride trihydrate 0°6279. 50 cc of ethylene glycol was added and reacted at 80°C for 2 hours. Ethyl orthosilicate 4 was added to the obtained ruthenium glycoxide solution.
4rnl was added and stirred at the same temperature for 3 hours to obtain a homogeneous mixture.

The entire amount of the homogeneous mixed solution and 50 cc of water were put into a 500 oct eggplant-shaped flask, and the flask was placed in a rotary evaporator. After hydrolysis was carried out at 80°C for 48 hours with stirring, degassing was carried out at the same temperature for 24 hours and at 140°C for 2 hours to remove water and unreacted ethylene glycol and ethyl orthosilicate. I got .49. The obtained hydrolysis product was filled into a quartz glass tube,
The catalyst was activated by increasing the temperature to 450° C. and maintaining this temperature for 8 hours while flowing hydrogen at a rate of 100 m/min. The composition of the obtained catalyst was 2
%Ru-3102.

Content volume sufficiently replaced with argon in advance 100-
A stainless steel autoclave was charged with 15 cc of water and 2.5 cc of ethylene glycol as an additive, and then 100 cc of the above catalyst and 15 cc of benzene were charged in that order.

Furthermore, hydrogen gas was introduced, and the reaction was carried out under stirring at a reaction pressure of 4.0 MPa and a temperature of 180° C. for 2 hours.

After the reaction was completed, the oil layer was taken out and the product was analyzed by gas chromatography, and the benzene conversion rate was 68.2 s.
The cyclohexene selectivity was 44.9%, and the cyclohexene yield was 30.6%. Note that the reaction product other than cyclohexene was only cyclohexane.

Comparative Example 1 A partial hydrogenation reaction of benzene was carried out for 1.5 hours by using the catalyst prepared in Example 1 and performing the same operations as in Example 1 except that ethylene glycol was not added. The cyclohexene selectivity was 61.7%, the cyclohexene selectivity was 40.2%, and the cyclohexene yield was 24.8%.

Comparative Example 2 Ruthenium trichloride was placed in an eggplant-shaped flask with a capacity of 5000C.
．． 1909, add 200 cc of water and dissolve. Commercially available 5in2 (Aerosil 200) 3
．． After adding 89, it was attached to a rotary volator. After impregnating at room temperature for 1 hour with stirring and at 60°C for 1 hour, the mixture was heated to 80°C under reduced pressure to evaporate water. The obtained evaporated dry product was filled into a quartz glass tube, and 100 tn
The catalyst was activated by increasing the temperature to 400° C. while flowing hydrogen at a rate of 1/min and maintaining this temperature for 4 hours. The composition of the obtained catalyst was 21Ru/S i02
It is.

15 cc of water was charged into a stainless steel autoclave having an internal volume of 1,004 cm, which had been sufficiently purged with argon in advance, and then 100 cc of the above catalyst and 15 cc of benzene were charged in this order.

Furthermore, hydrogen gas is introduced, and the reaction pressure is 4. Q MPa
When the reaction was carried out under stirring for 30 minutes at a temperature of 1806Cr19), the benzene conversion rate was 64.3%, the cyclohexene selectivity was 8.9%, and the cyclohexene yield was 5.7%.

Comparative Example 3 Using the catalyst produced in Comparative Example 3, the same operations as in Comparative Example 3 were carried out except that 2.5 da of ethylene glycol was added together with water as an additive, and the partial hydrogenation reaction of benzene was carried out for 1 hour. When conducted, the benzene conversion rate was 68.
．． 5, the cyclohexene selectivity was 7.6%, and the cyclohexene yield was 5.2%.

Examples 2 to 10 All the same as Example 1 except that the catalyst produced in Example 1 was used and 2.5 g of various aliphatic polyhydric alcohols listed in Table 1 were used instead of ethylene glycol as an additive.
When a partial hydrogenation reaction of benzene was carried out for 2 hours according to the method described in 1., the results shown in Table 1 were obtained.

Examples 11 to 14 The partial hydrogenation reaction of benzene was carried out in accordance with the method of Example 1, except that the catalyst prepared in Example 1 was used, glycerin was used as an additive, and the amount of glycerin added was changed. When the test was carried out for 2 hours, the results shown in Table 2 were obtained.

Comparative Example 4 A partial hydrogenation reaction of benzene was carried out for 6 hours using the catalyst prepared in Example 1, following the method of Example 1 except for using 2°5f of glycerin as an additive and not adding water. When conducted, the benzene conversion rate was 5.
9.9%, cyclohexene selectivity 21.5q6, and cyclohexene yield 12.9%.

Examples 15 to 18 Catalysts were produced in the same manner as in Example 1, except that the amount of ruthenium trichloride used was changed in the production of the catalyst in Example 1.

Contents sufficiently replaced with argon in advance 45j 10
15 bottles of water and 2.5 y of glycerin as an additive were charged into a stainless steel autoclave, and then 100 ml of the above catalyst and 15 ω of benzene were charged in this order. Furthermore, hydrogen gas is introduced and the reaction pressure is 4. QMPa, temperature 1
The reaction was carried out at 80° C. with stirring. The results are shown in Table 3.

(19 completed) 19A? −

Claims (1)

[Claims] After hydrolyzing a homogeneous solution of ruthenium alkoxide and alkyl silicate, a ruthenium-silica catalyst prepared by an activation treatment is used, and aromatic hydrocarbons are partially hydrogenated with hydrogen in the presence of water and additives to produce the corresponding cyclo A method for producing an olefin, characterized in that an aliphatic polyhydric alcohol having 2 to 6 carbon atoms is used as the additive.