JPH0683786B2 - Method for producing solid base - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a method for producing a catalyst. More specifically, the present invention relates to a method for producing a solid base, which is characterized in that hydrous alumina and an amount of an alkali metal hydride that exceeds an equivalent amount to the molar amount of water of the alumina are heated at a specific temperature. .

<Prior Art and Problems to be Solved by the Invention> Solid bases are industrially important catalysts and are used, for example, in reactions such as olefin isomerization, hydrogenation, and dehydrogenation.

Conventionally, a solid base in which an alkali metal is dispersed in an anhydrous carrier having a large surface area, such as activated carbon, silica gel, or alumina, is known (J. Am. Chem. Soc., 82 387 (196).
0)). However, such a solid base in which an alkali metal is simply dispersed is ignited and deactivated immediately when it comes into contact with air, which is a serious difficulty in terms of operability and safety. Further, the catalytic ability was also unsatisfactory.

On the other hand, as a solid base without the above problems, the present inventors have already proposed a new solid base made from alumina, alkali metal hydroxide and alkali metal, a new solid base made from hydrous alumina and alkali metal. Moreover, these solid bases are safer and industrially superior catalysts, unlike those in which alkali metals are simply dispersed in a carrier, without danger such as ignition in the air. I have found that (Japanese Patent Publication No. 50-3274, Japanese Patent Publication No. 57-21378). However, it is not always sufficiently satisfactory in terms of using an alkali metal as a raw material and in terms of catalytic ability.

A solid base having an alkali metal hydride supported on a carrier is also known (JP-A-53-121753 and JP-A-59-1347).
No. 36). However, since the solid base exhibits catalytic activity when used in combination with an auxiliary agent such as ammonia or hydrazine, not only the point where the auxiliary agent is industrially required but also the auxiliary agent is separated and removed in the step after the reaction. Therefore, there is a problem in that a device is required and the operation becomes complicated.

In order to solve the problems of the above-mentioned known solid bases, the present inventors have conducted extensive studies, and as a result, a solid base obtained by heating hydrous alumina and an alkali metal hydride under a specific temperature is used alone. However, it was found that the catalyst exhibited a remarkably high catalytic activity, and various studies were added to the catalyst to arrive at the present invention.

<Means for Solving Problems> That is, in the present invention, a hydrous alumina and an amount of an alkali metal hydride in an amount exceeding the equivalent amount to the molar amount of water of the alumina are added in an inert gas atmosphere at 200 to 500 ° C. The present invention provides an industrially excellent method for producing a solid base, which is characterized by being heated at a temperature.

As the hydrous alumina used in the present invention, various forms of hydrous alumina other than α-alumina are used.

Alumina is usually produced by calcining aluminum hydroxide, but it is known that various metastable structures are taken depending on the calcining temperature and calcining time, and the amount of water contained in it also varies, so that there are various forms of alumina. There is.

In the present invention, such alumina is mainly used.
In particular, hydrated alumina having a high surface area such as γ-type, χ-type and ρ-type is preferably used.

Alumina eventually becomes α- as the firing temperature increases.
It is said that it will be changed to alumina and the heating loss of alumina will disappear. Although it is not so easy to measure the amount of water contained in alumina, α-
It can be represented by the weight loss on heating until it changes to alumina. The water content of the hydrous alumina used in the present invention is usually 1.2 to 10% by weight, preferably 2 to 7% by weight.

Examples of the alkali metal hydride used in the present invention include hydrides such as sodium, potassium and lithium of Group 1 of the periodic table. It does not matter if two or more kinds of these alkali metal hydrides are used.

The amount of such an alkali metal hydride used should be an amount exceeding the equivalent amount to the molar amount of water of the hydrated alumina, and preferably 1.01 to 2 times equivalent amount to the moisture.

When the alkali metal hydride is allowed to act on the hydrated alumina, a predetermined amount of the alkali metal hydride may be added at a time, or the moisture of the hydrated alumina may be added in an equivalent amount to allow sufficient reaction, and then the remaining alkali metal hydrogen Compounds may be added. In the latter case, it does not matter if the alkali metal hydride added first is different from the alkali metal hydride added later. These alkali metal hydrides are generally easily available as a dispersion of powder or an inert catalyst such as liquid paraffin. In the case of a dispersion of an inert medium, the medium may be used after separating the medium, or together with the medium. It can also be separated after use.

Alternatively, a method of using an alkali metal, supporting it on hydrous alumina, and then causing it to act on hydrogen can be employed.

The present invention is to adjust the solid base by causing the above-mentioned hydrous alumina and alkali metal hydride to act at a specific temperature in an inert gas atmosphere, but as the inert gas, nitrogen, helium, or argon is used. Etc. are illustrated.

In the present invention, the preparation temperature, that is, the temperature at which the hydrous alumina and the alkali metal hydride are heated, is extremely important and significantly affects the catalytic activity. The preparation temperature in the present invention is 200 to 500 ° C, more preferably 250 to 450 ° C. If the solid base is prepared at such a temperature, a solid base having an unprecedentedly high catalytic activity can be obtained, and the target reaction can be efficiently completed with a small amount of catalyst.

The heating time varies depending on the selected temperature conditions, etc., but is usually 15
Minutes to 10 hours is sufficient.

The solid base of the invention is thus produced. It is considered that the hydrous alumina and the alkali metal hydride act on each other to form a new active species in the solid base, which has a significantly higher catalytic activity than known solid bases and does not have an auxiliary agent such as ammonia or hydrazine. In addition, since the desired reaction can be completed with a small amount, it is used for various industrial scale reactions.

For example, it can be used for various reactions such as isomerization of olefins and various condensation reactions promoted by a base. Among them, it exhibits an excellent catalytic action for the isomerization reaction of olefins, for example, in the case of isomerizing a terminal olefin to an internal olefin, especially at the room temperature for the isomerization of an alkenyl bridged ring compound to an alkylidene bridged ring compound. The reaction proceeds only by letting it run. Depending on the purpose of the reaction, it may be heated, but the desired reaction can be completed neatly at room temperature.

<Effects of the Invention> The solid base obtained by the method of the present invention can use an alkali metal hydride that is easy to handle as a raw material, and exhibits a remarkably high catalytic activity even without an auxiliary agent such as ammonia or hydrazine. The present invention is extremely advantageous as an industrial production method of a solid base, because it has the advantage that the target reaction can be completed.

<Example> The present invention will be described below with reference to specific examples, but the present invention is not limited thereto.

Example 1 25.0 g of γ-alumina containing 2.2% by weight of water was placed in a 100 ml flask and sodium hydroxide was added thereto in a nitrogen stream (after hexane was added to a commercial product under a nitrogen stream to wash and remove mineral oil). 1.28 g was added, and the mixture was heated to 350 ° C. with stirring and stirred at the same temperature for 1 hour. Then, the mixture was allowed to cool to room temperature to obtain 25.9 g of a solid base.

Examples 2 to 6 and Comparative Examples 1 to 3 The solid bases shown in Table 1 were obtained in the same manner as in Example 1 except that shown in Table 1.

Reference Example 1 0.13 g of the solid base prepared in Example 1 was placed in a 200 ml flask under a nitrogen atmosphere, 65.0 g of 5-vinyl-2-norbornene (purity 99.9%) was added thereto, and the solid base was added at 15 to 20 ° C. for 15 hours. When stirred and the reaction solution was measured by gas chromatography, 5-vinyl-2-norbornene (VNB) 0.3%, 5-
It was 99.6% of ethylidene-2-norbornene (ENB). The catalyst was removed from the reaction solution to obtain 64.8 g of a product.

Reference Examples 2 to 9 The isomerization reaction was carried out in the same manner as in Reference Example 1 except that the results shown in Table 2 were used in a 100 ml flask under a nitrogen atmosphere. The results are shown in Table-2.

Reference Example 10 0.24 g of the solid base prepared in Example 1 was placed in a 100 ml flask under a nitrogen atmosphere, and 5-isopropenyl-2-
Norbornene (End type 89.9%, Exo type 10.1%) 28.9
After adding g and stirring for 20 hours at 15 to 20 ° C., the reaction mixture was analyzed by gas chromatography to find that endo-5-isopropenyl-2-norbornene <0.1%, exo-5
-Isopropenyl-2-norbornene 0.3% and 5-isopropylidene-2-norbornene 99.3%.

Reference Example 11 0.25 g of the solid base prepared in Example 1 was placed in a 100 ml flask under a nitrogen atmosphere, and 4-methyl-1-pentene 2 was added thereto.
3.0 g was added, and the mixture was reacted at 15 to 20 ° C for 16 hours.

After the reaction, the reaction liquid was analyzed by gas chromatography to find that 4-methyl-1-pentene 0.4%, 4-methyl-2-pentene 9.2%, and 2-methyl-2-pentene 90.2.
%Met.

Reference Example 12 Under a nitrogen atmosphere, 0.24 g of the solid base prepared in Example 5 was placed in a 200 ml flask, and 4-methyl-1-pentene 3 was added thereto.
6.2 g was added and reacted at 15 to 20 ° C. for 8 hours.

After the reaction, the reaction solution was analyzed by gas chromatography to find that 4-methyl-1-pentene 0.3%, 4-methyl-2-pentene 9.8%, 2-methyl-2-pentene 89.9
%Met.

Reference Example 13 Under a nitrogen atmosphere, 0.30 g of the solid base prepared in Comparative Example 2 was placed in a 100 ml flask and 4-methyl-1-pentene was added thereto.
6.4g was added and it reacted at 15-20 degreeC for 48 hours.

After the reaction, the reaction solution was analyzed by gas chromatography to find that 4-methyl-1-pentene 89.3%, 4-methyl-2-pentene 6.8%, 2-methyl-2-pentene 3.9%.
Met.

Reference Example 14 Under a nitrogen atmosphere, 0.30 g of the solid base prepared in Comparative Example 3 was placed in a 100 ml flask, and 4-methyl-1-pentene 1 was added thereto.
5.3 g was added and reacted at 15 to 20 ° C. for 48 hours.

After the reaction, the reaction liquid was analyzed by gas chromatography to find that 4-methyl-1-pentene 0.6%, 4-methyl-2-pentene 27.9%, and 2-methyl-2-pentene 71.1.
%Met.

Claims (1)

[Claims] 1. A method in which hydrous alumina and an amount of an alkali metal hydride in an amount exceeding the equivalent amount to the molar amount of water of the alumina are heated at a temperature of 200 to 500 ° C. in an inert gas atmosphere. And a method for producing a solid base.