JPH06200B2 - Method for producing solid base catalyst - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a solid base catalyst. Specifically, in heating alumina, alkali metal hydroxide and alkali metal in an inert gas atmosphere to prepare a solid base catalyst, it is necessary to allow alumina, alkali metal hydroxide and alkali metal to act under a specific temperature. The present invention relates to a method for producing an improved solid base catalyst.

Solid base catalysts are industrially important catalysts, and are used for reactions such as isomerization, hydrogenation, dehydrogenation of olefins.

As such a solid base catalyst, a catalyst in which an alkali metal is dispersed in a carrier having a large surface area, for example, activated carbon, silica gel, alumina or the like has been conventionally known (J. Am. Chem.
Soc., 82, 387 (1960)). However, such a solid catalyst in which an alkali metal is dispersed in a carrier is ignited and deactivated when it comes into contact with air, which causes a big problem in terms of operability and safety.

To investigate such problems of the conventional solid base catalyst, the present inventors have already found a new solid base catalyst using alumina, alkali metal hydroxide and alkali metal as a raw material, This catalyst, unlike a catalyst in which only an alkali metal is dispersed in a carrier, has been found to be an industrially suitable catalyst without the risk of ignition even in air (Japanese Patent Publication No. 50-3274).

As a result of further studies on the solid base catalyst, the present inventors have found that the raw materials alumina, alkali metal hydroxide,
The preparation temperature at which an alkali metal reacts, particularly the temperature at which an alkali metal reacts is important, and it has been found that the catalyst activity is remarkably improved if prepared under a specific temperature condition, and further studies are carried out. Was completed.

That is, in the present invention, when an alumina, an alkali metal hydroxide and an alkali metal are heated in an inert gas atmosphere to produce a solid base catalyst, the alkali metal hydroxide is
It is allowed to react with alumina at 200 to 500 ℃ to remove alkali metal.
The present invention provides a method for producing a solid base catalyst having a remarkably high activity, which is characterized in that it is allowed to act at 200 to 350 ° C.

In the present invention, as the alkali metal, an alkali metal of the Ith series of the periodic table is used, and preferably sodium, potassium or an alloy thereof is used. Further, as the alkali metal hydroxide, lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide or the like is used, and its form is solid or liquid, and it is an aqueous solution. Is also good.

Regarding the combination of the alkali metal and the alkali metal hydroxide, the alkali metal and the corresponding alkali metal hydroxide, for example, a combination of sodium and sodium hydroxide, potassium and potassium hydroxide and the like are preferable, but Other alkali metal hydroxides that do not correspond thereto, for example, potassium and sodium hydroxide, sodium and potassium hydroxide, sodium and lithium hydroxide and the like may be used in combination, but industrially, a combination of sodium hydroxide and metal sodium is preferable. . The amounts of the alkali metal and alkali metal hydroxide used are 2 to 10% by weight and 5 to 40% by weight, respectively, based on alumina.
Is preferable in terms of contact activity.

As the alumina, various forms of alumina having a large surface area are usually used, and it is particularly preferable to use γ-alumina of 100 to 300 mesh in terms of catalytic activity. Alumina also interacts with alkali metals and alkali metal hydroxides to form some kind of new bond, and also serves as a carrier, so that in addition to alumina, alumina-containing substances such as kaolin and alumina silicate are also included. Although it can be used, the above-mentioned alumina is preferable.

The present invention prepares a catalyst by allowing the above-mentioned alumina, alkali metal hydroxide and alkali metal to act at a specific temperature in an inert gas atmosphere. Most preferably, an alkali metal hydroxide is allowed to act, and then an alkali metal is allowed to act. Further, examples of the inert gas include nitrogen, helium, and argon.

In the present invention, the temperature during the preparation of the catalyst is extremely important, and above all, the temperature at which the alkali metal acts has a significant influence on the activity of the catalyst.

The temperature at which alumina and alkali metal hydroxides act is
The temperature is 200 to 500 ° C, more preferably 250 to 450 ° C, and the temperature at which the alkali metal acts is 200 to 350 ° C.
By preparing the catalyst at such a temperature, a remarkably highly active catalyst which has never been obtained can be obtained, and the target reaction can be completed efficiently with a small amount of the catalyst.

The heating time varies depending on the selected temperature conditions, etc., but the step of applying the alkali metal hydroxide is usually 0.5 to 10
The time is sufficient, and the step of reacting the alkali metal is usually 10 to 300 minutes.

Thus, the solid base catalyst of the present invention is produced. The solid base catalyst has no danger of ignition, has a significantly higher activity than known solid base catalysts, and can complete the desired reaction even in a small amount, and thus is used in various industrial scale reactions.

For example, it can be used for various reactions such as i) isomerization of olefins, ii) dehydrogenation, iii) hydrogenation of unsaturated bonds, iv) various condensation reactions, and v) other reactions catalyzed by bases. However, it exhibits excellent catalytic action for olefin isomerization, and for example, when olefin is isomerized to internal olefin, contact is only made at room temperature for isomerization of an alkenyl bridged ring compound to an alkylidene bridged ring compound. Isomerization proceeds.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the examples.

Example 1 31.9 g of γ-alumina was placed in a 100 ml flask, heated to 490 to 500 ° C. under a nitrogen gas flow, and stirred at the same temperature for 1 hour. The temperature was lowered to 300 to 310 ° C., 4.5 g of sodium hydroxide was added, and the mixture was stirred at the same temperature for 3 hours.

Next, 1.5 g of metallic sodium was added, and the mixture was stirred at the same temperature for 1 hour and then cooled to room temperature to obtain 34.9 g of a solid base.

Reference Example 1 82.5 g of 5-vinyl-2-norbornene (hereinafter abbreviated as VNB) was added to a 200 ml flask, and after nitrogen substitution, 0.25 g of the solid base prepared in Example 1 was added and stirred at 15 to 20 ° C. for 6 hours. .

Then, the catalyst was passed through to obtain 81.9 g of a reaction solution. When this product was analyzed by gas chromatography, VN
B was 0.5% and 5-ethylidene norbornene (hereinafter abbreviated as ENB) was 99.4%.

Example 2 31.9 g of γ-alumina was placed in a 100 ml flask, heated to 490 to 500 ° C. under a nitrogen gas flow, and stirred at the same temperature for 1 hour. The temperature was lowered to 300 to 310 ° C., 3.0 g of sodium hydroxide was added, and the mixture was stirred at the same temperature for 3 hours.

Next, 1.2 g of metallic sodium and 0.3 g of metallic potassium were added, and the mixture was stirred at the same temperature for 0.5 hours and then cooled to room temperature to obtain 33.8 g of a solid base.

Examples 3 to 7 and Comparative Examples 1 and 2 The solid base catalysts shown in Table 1 were obtained in the same manner as in Example 1 except for the conditions shown in Table 1.

Reference Examples 2 to 9 VN was carried out in the same manner as in Reference Example 1 except that the solid base catalysts prepared in Examples 2 to 7 and Comparative Examples 1 and 2 were used, except for the conditions shown in Table 2.
The isomerization of B was performed. The results are shown in Table 2.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akemi Sogabe 2-10-1 Tsukahara, Takatsuki City, Osaka Prefecture Sumitomo Chemical Co., Ltd. (56) References Japanese Patent Publication No. 50-3274 (JP, B1)

Claims (1)

[Claims] 1. When heating alumina, alkali metal hydroxide and alkali metal in an inert gas atmosphere to produce a solid base catalyst, the alkali metal hydroxide is allowed to react with alumina at 200 to 500 ° C. A process for producing a solid base catalyst, which comprises reacting a metal at 200 to 350 ° C.