KR100251346B1 - A manufacturing method of 5-ethyllidene -2 norbornene - Google Patents

Abstract

PURPOSE: A method for preparing 5-ethylidene-2-norbornene is provided to solve problems of operation and safety occurred on adding solid alkali metal compound, improve dispersibility of alkali metal compound and reduce the employed amount of the alkali metal compound. CONSTITUTION: 5-Ethylidene-2-norbornene(ENB) is produced by isomerizing 5-vinyl-2-norbornene in the presence of the solid basic catalyst. The isomerization is carried out for 0.5-6 hours at -30 to 100deg.C in the presence of the solid catalyst prepared by immersing the alkali metal to a carrier at 200-400deg.C. The carrier is prepared by infiltrating alkali metal compound into alumina and then baking them. The method provides high yields of ENB.

Description

Method for preparing 5-ethylidene-2-olbornene

The present invention relates to a method for producing 5-ethylidene-2-olbornene, and more particularly, alkali metal such as sodium in a carrier prepared by infiltration and calcining an alkali metal compound such as alkali metal hydroxide into alumina and firing. The present invention relates to an isomerization reaction of 5-vinyl-2-norbornene in the presence of a solid base catalyst prepared by supporting the above to produce 5-ethylidene-2-nolvonene in high yield.

5-ethylidene-2-norbornene (hereinafter referred to as "ENB") is well known as a very useful compound as a tertiary copolymer of ethylene, propylene and diene monomer, i.e. as a third component of EPDM. . In general, ENB is prepared by isomerizing 5-vinyl-2-norbornene (hereinafter referred to as "VNB") obtained by reacting 3-butadiene and cyclopentadiene in the presence of a catalyst. have.

As a liquid catalyst used in the isomerization reaction, an alkali metal compound, a nonprotonic solvent, an alkali metal amide and amines, or a mixture of an organic alkali metal and a fatty acid amine is known. However, when using a liquid base as a catalyst, the catalyst activity is not sufficient, and in addition to using a large amount of expensive reagents, the separation and recovery of the catalyst from the reaction mixture is complicated, the recovery rate is low, and a large amount of energy There is a problem of consumption.

In addition, as a solid catalyst used in the isomerization reaction, a catalyst obtained by dispersing an alkali metal with a large surface area such as activated carbon, silica gel, or alumina is known. Since it is dispersed in and ignited by contact with air and loses activity, it has not only a large difficulty in terms of operability and safety but also is not satisfactory in the isomerization ability.

Recently, solid base catalysts prepared by sequentially supporting alkali metal hydroxides and alkali metals on an alumina support have been used to safely isomerize olefins such as VNB without risk of ignition in air. And European Patent Application No. 219,637. However, in the production method of such a solid base catalyst, since alkali metal hydroxide is added in a solid state, the dispersibility of the alkali metal hydroxide on the alumina support is not good, so that the supporting efficiency in the following alkali metal supporting process is poor and there is room for improvement. In other words, the alkali metal is supported on the alkali metal hydroxide to form an effective solid base point. If the alkali metal hydroxide is poor in dispersibility, a substantial portion of the alkali metal is in direct contact with the alumina surface and thus does not produce an effective base point. Will occur. In addition, in the method for preparing a solid base catalyst, the alkali metal hydroxide should be added to the alumina and then stirred vigorously for 2 to 3 hours or more at a high temperature above the melting point of the alkali metal hydroxide. It involves the risk of fire. That is, there is a problem that the risk of operability and stability in the following alkali metal supporting process depending on the catalyst production temperature and the degree of stirring.

Accordingly, the present invention has been made to study how to efficiently improve the problems of operability and stability caused by the conventional method for preparing a solid base catalyst and to increase the dispersibility of alkali metal compounds such as alkali metal hydroxides and alkali metals. As a result, in the preparation of the solid base catalyst, instead of dispersing the alkali metal compound in the calcined alumina support, it is possible to use the support made by infiltrating and calcining the water-soluble alkali metal compound in the alumina, so that the operability and stability generated when adding the alkali metal compound in the solid state It is possible to solve the problem of, and the solid base catalyst prepared by this method has completed the present invention by knowing that the catalytic activity during the isomerization of VNB is significantly improved compared to the conventional catalyst.

Accordingly, an object of the present invention is to provide a method for producing ENB in a high yield using a solid base catalyst having excellent catalytic activity for a unit catalyst active ingredient by improving the dispersibility of alkali metal compounds and reducing the amount of alkali metal used. have.

Hereinafter, the present invention will be described in detail.

The present invention is a method for producing 5-ethylidene-2-norbornene by isomerization of 5-vinyl-2-norbornene in the presence of a solid base catalyst, wherein the alkali base compound is infiltrated into alumina as the solid base catalyst. It is characterized by a method for producing 5-ethylidene-2-olbornene using a solid base catalyst prepared by carrying an alkali metal at 200 to 400 ° C. on a carrier prepared by calcining.

Referring to the present invention in more detail as follows.

The present invention is characterized by a method for producing a solid base catalyst which is used to prepare ENB by isomerizing VNB. In the present invention, before calcination of the alumina support, water-soluble alkali metal compound is dispersed in alumina by infiltration and water is used. After evaporation and firing, the dispersion degree of the alkali metal compound was sufficiently improved, and then the alkali metal was supported to increase the contact ratio between the alkali metal compound and the alkali metal, thereby maximizing the efficiency of the catalyst.

Hereinafter, the manufacturing process of the solid base catalyst used in the present invention will be described in more detail.

First, a water-soluble alkali metal compound in which the alkali metal compound is dissolved in water is added to alumina, for example, gamma alumina, boehmite, or a mixture thereof, so as to infiltrate the alumina pores evenly and evaporate excess water. After the impregnation process, the substrate is baked at 400 to 800 ° C. for 6 to 48 hours to prepare a support. At this time, the alkali metal compound is one or more selected from among alkali metal hydroxides, alkali metal acetates and alkali metal formates, and is used in an amount of 5 to 30 parts by weight based on 100 parts by weight of alumina. If less than 5 parts by weight of the alkali metal compound is used, there is a problem of not sufficiently covering the surface of the alumina, and if it exceeds 30 parts by weight, the alkali metal compound is oversaturated in the alumina pores. If the firing temperature is less than 400 ° C., the moisture in the support may not be sufficiently removed. If the firing temperature exceeds 800 ° C., the surface area of the support may be reduced, which is not preferable.

Then, a solid base catalyst is prepared by raising the temperature of the support to 310 to 320 ° C. under nitrogen atmosphere and then adding an alkali metal. In this case, an alkali metal single compound or a mixture of two or more alkali metals may be used as the alkali metal. Alkali metal is supported by 1 to 5 parts by weight based on 100 parts by weight of alumina. If the supported amount of alkali metal is less than 1 part by weight, the activity of the catalyst is reduced by lowering the concentration of the active substance. The more contact of, the less the formation of the superbase point by the action with the support.

The ENB is prepared by isomerizing VNB in the presence of the solid base catalyst prepared above and in a nitrogen atmosphere. The isomerization reaction is performed at -30 to 100 ° C for 0.5 to 6 hours. If the temperature of the isomerization reaction is less than -30 ℃ reaction rate is lowered, if it exceeds 100 ℃ there is a possibility of the formation of by-products. In the presence of a solid base catalyst prepared by the preparation method of the present invention, the yield of ENB was 96% or more.

According to the catalyst preparation method of the present invention as described above, by infiltrating and calcining the water-soluble alkali metal compound in alumina and using a support, it solves the problems of operability and stability generated when the alkali metal compound is added in a solid state, as well as alkali to alumina. By increasing the dispersibility of the metal compound, the contact ratio of the next supported alkali metal and alkali metal compound was increased, thereby increasing the unit activity of the alkali metal as the catalyst active ingredient, thereby increasing the efficiency of the catalyst.

In addition, when ENB was prepared by isomerizing VNB using the solid base catalyst of the present invention, catalytic activity was improved by about 2 times per unit alkali metal compared to the conventional solid base catalyst.

When the present invention is described in more detail based on the embodiments as follows, the present invention is not limited thereto.

Example 1

An aqueous solution in which sodium hydroxide (NaOH, 1.5 g) was dissolved in distilled water (20 ml) was added to gamma alumina (10 g), stirred, and evaporated under reduced pressure, and then calcined at 500 ° C. for 24 hours. The temperature was raised to 320 ° C. under a nitrogen atmosphere, and then sodium (Na, 0.24 g) was added thereto. After stirring for 1 hour at 320 ℃, cooled to room temperature to prepare a solid base catalyst.

The solid base catalyst (0.1 g) prepared above and 5-vinyl-2-olbornene (15 g) were reacted at room temperature for 3 hours under a nitrogen atmosphere. The production yield of 5-ethylidene-2-norbornene (ENB) was measured by analysis using gas chromatography, and the results are shown in Table 1 below.

EXAMPLES 2-16

A solid base catalyst was prepared in the same manner as in Example 1, except that the amounts of alkali metal compounds and alkali metals were different. In addition, 5-ethylidene-2-norbornene was prepared by reacting the above-described solid base catalyst (0.1 g) and 5-vinyl-2-norbornene (15 g) at room temperature under nitrogen atmosphere for 3 hours. The yield of 5-ethylidene-2-olbornene (ENB) was measured by gas chromatography, and the results are shown in Table 1 below.

TABLE 1

Comparative Example 1

Sodium hydroxide (NaOH, 1.5 g) was added to the gamma alumina (10 g) calcined at 500 ° C. for 24 hours at 320 ° C., and then water was removed under nitrogen stream with stirring and stirred at 320 ° C. for 3 hours. The temperature was raised to 320 ° C. under a nitrogen atmosphere, and then sodium (Na, 0.24 g) was added thereto. After stirring for 1 hour at 320 ℃, cooled to room temperature to prepare a solid base catalyst.

The solid base catalyst (0.1 g) prepared above and 5-vinyl-2-olbornene (15 g) were reacted at room temperature for 3 hours under a nitrogen atmosphere. As a result of analysis using gas chromatography, the yield of 5-ethylidene-2-norbornene (ENB) was 44.22 mol%.

Comparative Example 2

A solid base catalyst was prepared in the same manner as in Comparative Example 1, except that sodium metal (Na, 0.32 g) was added. In addition, the solid base catalyst (0.1 g) prepared above and 5-vinyl-2-olbodene (15 g) were reacted at room temperature for 3 hours under a nitrogen atmosphere. As a result of analysis using gas chromatography, the yield of 5-ethylidene-2-norbornene (ENB) was 82.68 mol%.

Comparative Example 3

A solid base catalyst was prepared in the same manner as in Comparative Example 2, and the prepared solid base catalyst (0.1 g) and 5-vinyl-2-olbodene (15 g) were reacted at room temperature for 2 hours under a nitrogen atmosphere. As a result of analysis using gas chromatography, the yield of 5-ethylidene-2-norbornene (ENB) was 70.14 mol%.

Claims (6)

In the process for isomerization of 5-vinyl-2-norbornene in the presence of a solid base catalyst to produce 5-ethylidene-2-norbornene, the disulfide reaction is carried out by infiltration of an alkali metal compound into alumina and then calcined. 5-ethylidene-2-, characterized in that carried out for 0.5 to 6 hours in the temperature range of -30 to 100 ℃ in the presence of a solid base catalyst prepared by supporting the alkali metal on the prepared carrier at 200 to 400 ℃ Process for producing nolvone. According to claim 1, wherein the alkali metal compound is one or more selected from alkali metal hydroxide, alkali metal acetate and alkali metal formate, 5 to 30 parts by weight based on 100 parts by weight of alumina is used. Process for the preparation of lidene-2-olbornene. The method of claim 1, wherein the alkali metal is used in the production of 5-ethylidene-2-olbornene, characterized in that 1 to 5 parts by weight based on 100 parts by weight of alumina as an alkali metal compound or a mixture of two or more alkali metals. Way. The method of claim 1, wherein the alumina is gamma alumina, boehmite, or a mixture thereof. 5. The process of claim 1, wherein the infiltration process comprises a step of adding an aqueous solution of an alkali metal compound dissolved in water to the alumina to infiltrate the alumina pores evenly, and then removing excess water by evaporation. Process for the preparation of lidene-2-olbornene. The method of claim 1, wherein the firing is performed at 400 to 800 ° C.