JPH0819011B2 - Internal olefin manufacturing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an internal olefin, and more particularly to a method for producing a more stable internal olefin by isomerizing an olefin in the presence of a specific catalyst.

[0002]

2. Description of the Related Art Various methods for isomerizing olefins to produce more stable internal olefins are known. For example, as a catalyst for the isomerization reaction, a method using a catalyst in which an alkali metal is dispersed in a carrier having a large surface area, such as activated carbon, silica gel, alumina or the like is known (J. Am. Chem.
c. , 82 , 387 (1960)). However, a solid base in which an alkali metal is simply dispersed on a carrier has a big problem in terms of operability, safety, etc. because it ignites and deactivates when contacted with air. Moreover, the catalytic ability was also unsatisfactory. The present inventors have found a new solid base starting from alumina, alkali metal hydroxide, and alkali metal as an isomerization catalyst that has solved such various drawbacks, and if this one only exhibits high catalytic activity. It has been found that it does not ignite even in the air, is safer, and is excellent as an industrial catalyst (Japanese Patent Publication No. 50-3274). However, it is not always sufficiently satisfactory in terms of using an alkali metal as a raw material.

On the other hand, a solid catalyst in which an alkali metal hydride is supported on a carrier such as alumina is also known (JP-A-53).
-121753 and 59-134736). However, since such a solid catalyst using an alkali metal hydride shows catalytic activity by using a cocatalyst such as ammonia or hydrazine in combination,
When using this solid catalyst, in addition to the problem that ammonia, hydrazine, etc. are separately required, a purification device for separating and removing these after the reaction is also required, and there is a problem that the operation becomes complicated. Was there. The present inventors, as a result of intensive studies to solve the problems of the known method,
A solid base obtained by heating alkali metal hydride and alumina pretreated with an alkali metal salt of carbonic acid or aluminate as a catalyst at a specific temperature shows not only extremely high activity but also safely. The present invention was completed by finding out that it can be handled and is extremely excellent as an industrial catalyst, and further various investigations were made.

[0004]

[Means for Solving the Problems] That is, the present invention, in isomerizing a double bond of an olefin, is pretreated with an alkali metal hydride and an alkali metal salt of carbonic acid or aluminate as a catalyst in an inert gas atmosphere. The present invention provides an industrially excellent process for producing an internal olefin, which comprises using a solid base obtained by heating the above-mentioned alumina under heating at a temperature of 200 to 450 ° C.

Examples of the alkali metal hydride which is a raw material of the solid base in the present invention include hydrides of Group I sodium, potassium and the like. Two or more kinds of alkali metal hydrides can be used. The alkali metal hydride is usually used in an amount of 2 to 15% by weight, preferably 4 to 10% by weight, based on alumina. Examples of alumina pretreated with an alkali metal salt of carbonic acid or aluminate include sodium, potassium of Group I of the periodic table,
Examples thereof include alumina pretreated with carbonates, aluminates and the like of alkali metals such as lithium, rubidium and cesium.

As the alumina to be treated, various forms of alumina other than α-alumina are used, and in particular γ-, χ-,
High surface area alumina such as ρ- and η-type is preferably used. A water-containing product can also be used. Alumina interacts with alkali metal hydrides, alkali metal salts of carbonic acid, alkali metal salts of aluminate, etc. to form a certain kind of new bond and also functions as a carrier. Alumina-containing materials such as alumina silicate can also be used, but the above-mentioned alumina is preferable. The pretreatment of alumina is usually carried out by impregnating the aqueous solution of the alkali metal salt and then calcining. The amount of alkali metal salt impregnated is usually 5 to 30 wt% with respect to alumina, preferably 5 to 25.
wt%, and the firing temperature is usually 300 to 700 ° C.

The solid base used in the present invention is prepared by heating an alkali metal hydride and alumina pretreated with an alkali metal salt of carbonic acid or aluminate at a specific temperature in an inert gas atmosphere. However, examples of the inert gas include nitrogen, helium, and argon.

The preparation temperature of the solid base of the present invention is extremely important, especially the temperature at which the alkali metal hydride and the alumina pretreated with the alkali metal salt are heated, and the catalyst activity is significantly affected. Exert.
The preparation temperature is 200 to 450 ° C, preferably 220 to 400 ° C, more preferably 250 to 400 ° C.
By preparing a solid base at such a temperature, an unprecedentedly highly active isomerization catalyst 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 1
About 5 minutes to 10 hours is sufficient.

Thus, the solid base used in the present invention is produced. It is considered that alumina, alkali metal salt and alkali metal hydride act on each other to form a new active species, The desired reaction can be completed without an auxiliary agent such as ammonia or hydrazine and in a small amount. The present invention uses such a solid base catalyst to isomerize an olefin into a more stable internal olefin, and examples of such a raw material olefin include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-
Nonene, 1-decene, 2-methyl-1-butene, 3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, 2-methyl-1-pentene, 2,
Chain compounds such as 3-dimethyl-1-butene, aromatic compounds such as allylbenzene and allyltoluene, 2-isopropenylnorbornane, 5-vinyl-2-norbornene,
5-isopropenyl-2-norbornene, 6-methyl-
Crosslinked ring compounds such as 5-vinylnorbornene, cyclic compounds such as methylenecyclopentane and methylenecyclohexane, 1,4-pentadiene, 1,5-hexadiene,
Terminal olefin compounds such as non-conjugated olefins such as 2,5-dimethyl-1,4-hexadiene and 2,5-dimethyl-1,5-hexadiene, 4-methyl-2-pentene, 5- (2-propenyl)- Examples thereof include compounds having a double bond other than the terminal such as 2-norbornene and capable of isomerizing at a more stable position.

In isomerizing olefins,
The amount of solid base catalyst used is usually 1 with respect to the raw olefin.
/ 1000 to 1/20 weight, 1/500 to 1
/ 100 weight is also sufficient. Further, the isomerization temperature does not need to be particularly warmed because the reaction proceeds sufficiently even at room temperature,
It may be heated depending on the purpose. Usually -30 to 120
It is carried out in the temperature range of ℃, preferably -10 to 100 ℃. If necessary, the reaction can be carried out by diluting with an inert medium, for example, a hydrocarbon solvent such as pentane, hexane, cyclohexane, heptane, dodecane, etc., but after the reaction, the desired high-quality isomerization can only be achieved by separating the catalyst. Since the above-mentioned olefin can be obtained, a medium-free solvent or a solvent used in the next step may be selected.

The method of the present invention can be carried out by either a batch method or a continuous method, and it is also effective to pretreat the raw material with a desiccant such as alumina in advance for isomerization. In order to carry out isomerization more safely and surely, it may be carried out under an inert gas atmosphere. The isomerization reaction product is analyzed by a known method such as gas chromatography and is easily separated from the catalyst by filtration, decantation or the like.

[0012]

As described above, an olefin having a double bond isomerized at a more stable position, which is the object of the present invention, can be obtained. According to the present invention, an alkali metal hydride which is easy to handle and easily available as a raw material is obtained. Can be used, and the isomerization ability is extremely high even without an auxiliary agent such as ammonia or hydrazine, and the olefin isomerization can be completed very efficiently even with a small amount of catalyst, which is extremely advantageous as an industrial production method of internal olefins. is there. In addition, since the target product is selectively produced with almost no by-products such as a polymerized product, and the target product of high quality can be obtained only by separating the catalyst, the present invention is also advantageous in this respect.

[0013]

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

Reference Example 1 Sodium aluminate 23.5 g in a 300 ml flask
And 200 ml of water were added to dissolve sodium aluminate. Next, 109 g of γ-alumina was added to this, and the temperature was 60 ° C.
The water was distilled off under reduced pressure while heating and stirring to 133.
3 g of powder was obtained.

Reference Example 2 In the same manner as in Reference Example 1 except that 15 g of sodium carbonate was used instead of sodium aluminate, 123.3 g of powder was obtained.

Reference Example 3 25 g of the powder obtained in Reference Example 1 was placed in a 100 ml flask, heated at 450 ° C. for 2 hours while stirring in a nitrogen stream, and then allowed to cool. Next, add 1.1 g of sodium hydride (a commercially available product was washed with hexane under a nitrogen atmosphere, washed, filtered, dried after removing mineral oil), heated to 350 ° C. with stirring and kept at the same temperature for 1 hour. After heating and stirring, the mixture was allowed to cool to obtain 24.1 g of a solid base.

Reference Examples 4 to 13 Solid bases shown in Table 1 were obtained in the same manner as in Reference Example 3 except that shown in Table 1.

Table-1 Alumina Alkali Metal Hydride Example Reference Example No. Heating Time Hydride Usage Temperature Time Reference Example 4 12 hr NaH 1.1g 250 ° C 3hr Reference Example 5 12 KH 1.8 300 1 Reference Example 6 24 NaH 1.1 350 1 Reference example 7 2 4 NaH 1.1 250 3 Reference example 8 1 2 NaH 1.1 400 1 Reference example 9 2 4 NaH 1.1 400 1 Reference example 10 1 2 NaH 1.1 170 1 Reference example 11 1 2 NaH 1.1 510 1 Reference example 12 2 4 NaH 1.1 170 1 Reference example 13 2 4 NaH 1.1 510 1

Example 1 Under a nitrogen atmosphere, 0.21 g of the solid base prepared in Example 1 was placed in a 150 ml flask, and 5-vinyl-2 was added thereto.
-Add 76.0 g of norbornene (purity 99.9%),
The mixture was stirred at 15 to 20 ° C for 10 hours. After the reaction, the reaction solution was analyzed by gas chromatography to find that it was 0.5-vinyl-2-norbornene (hereinafter referred to as VNB).
%, 5-ethylidene-2-norbornene (hereinafter, ENB
It was 99.4%. The catalyst was filtered off and 75.4
g product was obtained.

Examples 2 to 7 and Comparative Examples 1 to 4 VNB was isomerized in the same manner as in Example 1 except that shown in Table 2. The results are shown in Table-2.

[0021] Table 2 Solid body salt group VNB reaction reaction results Examples Reference Example No. During time usage amount VNB ENB Example 2 4 0.25g 33 g 10hr 0.7% 99.2% Example 3 5 0.22 65.8 6 0.3 99.6 Example 4 8 0.25 48.5 10 0.4 99.5 Comparative Example 1 10 0.3 15 24 99.8 0.1 Comparative Example 2 11 0.3 15 20 13.7 86.2 Example 5 6 0.2 69.4 10 0.5 99.4 Example 6 7 0.25 33.8 10 0.4 99.5 Example 7 9 0.24 45.3 10 0.4 99.5 Comparative example 3 12 0.3 15 24 99.7 0.2 Comparative example 4 13 0.3 15 20 6.1 93.8

Example 8 A glass tube with an outer tube having an inner diameter of 5 mmΦ and a length of 100 mm and a solid base of 0.9 prepared in Reference Example 3 under a nitrogen atmosphere.
Charged 6 g. Cooling water at 15 to 20 ° C. was flown in the outer tube, and VNB (purity 99.9%) was flown in from the upper part of the inner tube at a flow rate of 3.4 g / hr. The composition of the reaction liquid flowing out from the lower part of the reactor was as follows. Time (hr) VNB (%) ENB (%) 15 0.3 99.5 25 0.3 0.3 99.5 35 0.3 99.5 45 0.3 99.5 Total outflow 151.7 g, ENB average purity It was 99.5%.

Example 9 In a 100 ml flask, under a nitrogen atmosphere, 0.25 g of the solid base prepared in Reference Example 3 was placed and 4-methyl-1-
Pentene (17.5 g) was added, and the mixture was stirred at 15 to 20 ° C for 16 hr. After the reaction, the reaction solution was analyzed by gas chromatography to find that 4-methyl-1-pentene 0.4
%, 4-methyl-2-pentene 8.9%, 2-methyl-2
-Pentene 90.5%.

Example 10 In a 200 ml flask, under a nitrogen atmosphere, 0.25 g of the solid base prepared in Reference Example 4 was placed, and 4-methyl-1 was added thereto.
-Pentene 36.2g was added and it stirred at 15-20 degreeC for 8 hours. When the reaction solution was analyzed in the same manner as in Example 9, it was 4
It was 0.4% of methyl-1-pentene, 9.4% of 4-methyl-2-pentene, and 90.2% of 2-methyl-2-pentene.

Comparative Example 5 Under a nitrogen atmosphere, 0.3 g of the solid base prepared in Reference Example 10 was placed in a 100 ml flask, and 4-methyl-1 was added thereto.
-Pentene 6g was added and it stirred at 15-20 degreeC for 48 hours. After the reaction, when analyzed in the same manner as in Example 9, the results were 90.7% of 4-methyl-1-pentene, 5.8% of 4-methyl-2-pentene, and 3.3% of 2-methyl-2-pentene. It was

Example 11 In a 100 ml flask, under a nitrogen atmosphere, 0.25 g of the solid base prepared in Reference Example 7 was placed, and 4-methyl-1 was added thereto.
-Pentene 18g was added and it stirred at 15-20 degreeC for 16 hours. When the reaction solution was analyzed in the same manner as in Example 9, it was found that 4-
It was 0.5% of methyl-1-pentene, 8.9% of 4-methyl-2-pentene, and 90.4% of 2-methyl-2-pentene.

Example 12 In a 200 ml flask, under a nitrogen atmosphere, 0.25 g of the solid base prepared in Reference Example 6 was placed, and 4-methyl-1 was added thereto.
-Pentene 36.3g was added and it stirred at 15-20 degreeC for 8 hours. After the reaction, when analyzed in the same manner as in Example 9, 4
It was 0.4% of -methyl-1-pentene, 8.8% of 4-methyl-2-pentene, and 90.6% of 2-methyl-2-pentene.

Comparative Example 6 Under a nitrogen atmosphere, 0.31 g of the solid base prepared in Reference Example 12 was placed in a 100 ml flask, and 4-methyl-
1-Pentene (6 g) was added, and the mixture was stirred at 15 to 20 ° C for 48 hr. When the reaction solution was analyzed in the same manner as in Example 9, it was found that 4-
Methyl-1-pentene was 89.3%, 4-methyl-2-pentene was 6.7%, and 2-methyl-2-pentene was 3.8%.

Continuation of front page (56) Reference JP-A-64-19027 (JP, A) JP-B-49-35264 (JP, B1) JP-B-48-8081 (JP, B1) JP-B 5-81570 (JP , B2) Japanese Patent Publication 6-74220 (JP, B2) Japanese Patent Publication 6-74221 (JP, B2)

Claims (1)

[Claims] 1. When isomerizing an olefin to produce a stable internal olefin, an alkali metal hydride and alumina pretreated with an alkali metal salt of carbonic acid or aluminate in an inert gas atmosphere are used as catalysts in an amount of 200 to 200. A process for producing an internal olefin, which comprises using a solid base obtained by heating at a temperature of 450 ° C.