JPH0254807B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel process for producing 4-methyl-1-pentene by dimerizing propylene.

By polymerizing 4-methyl-1-pentene, a polymer with high transparency and excellent heat resistance, mechanical and electrical properties, and chemical resistance can be obtained. It is a compound that shows particularly excellent performance as a comonomer for improving various physical properties of polyolefin products, such as transparency and environmental stress cracking resistance, when producing polyolefins by polymerizing them.

Traditionally, propylene has been dimerized in the presence of alkali metals such as sodium and potassium.
-Methyl-1-pentene is known to be obtained (e.g. J.Org.Chem., 30, 3286 (1965)).
(reported by AWShow et al.).

In addition, when carrying out the duplication reaction of propylene in the presence of an alkali metal, alcohol (Japanese Patent Publication No. 8701) and phenol (Japanese Patent Publication No. 38-8701) are used as reaction accelerators.
39-19622), tertiary amines (JP-A-49-93303)
It is also known to use the following.

Furthermore, using a catalyst with an alkali metal supported on a carrier, propylene was dimerized into 4-methyl-
It is also known that it is possible to obtain 1-pentene. In this case, graphite, potassium carbonate, alkali metal silicate, alkali metal halide, magnesium sulfate, talc, and the like are used as the carrier.

However, these and other known methods have relatively low yields of propylene dimer and selectivity for 4-methyl-1-pentene, and in addition to the desired 4-methyl-1-pentene, cis and
trans 4-methyl-2-pentene, 2-methyl-1-pentene, 2-methyl-2-pentene, 1
-hexene, cis and trans 2-hexene, and cis and trans 3-hexene were produced in large quantities as by-products. Furthermore, these isomers have close boiling points to each other, and in order to obtain the desired 4-methyl-1-pentene with sufficient purity, a precise distillation operation is required, resulting in a large cost for purification. It also had.

In addition, many of the catalysts used in these known methods have a long induction period, which requires a long time to reach their maximum activity, and it takes a long time for the reaction to stabilize, resulting in poor economic efficiency and stable operation. But there were many things that were inferior. In addition, many of these known dimerization catalysts have not only dimerization ability but also polymerization ability, and the polymerization reaction proceeds along with the dimerization reaction, and the generated polymer covers the catalyst surface and gradually becomes active. There were times when I lost my life. In particular, when such a catalyst is used, it has often been observed that the selectivity tends to decrease as the activity decreases. The catalyst that has lost its activity in this way has been solidified by the resinous polymer inside the reactor, but there is still a sufficiently highly active catalyst remaining inside the reactor, and catalyst replacement is possible. Therefore, when extracting this waste catalyst, there is a risk of ignition due to contact with atmospheric oxygen, moisture, etc.
Another disadvantage was that it was inconvenient to handle due to the danger of fire.

The present inventors conducted intensive research to improve the drawbacks of conventionally known methods and catalysts as described above, and as a result, discovered a method using a new catalyst system as disclosed in JP-A-57-126426. Ta. This method uses a compound represented by K ₂ O・xAl ₂ O ₃ (1) as a support for the reaction catalyst (in the above formula, x is
0.5≦x≦11, preferably 1≦x≦5) on which sodium and/or sodium amide is supported, and furthermore, this which has been subjected to hydrogen treatment in advance is used as a catalyst. It dimerizes propylene. According to this method, it is not only possible to improve the drawbacks of conventional methods using various catalysts, but also it is possible to increase the amount of sodium supported on the carrier,
It has been found that the reaction rate and the selectivity for 4-methyl-1-pentene can be increased significantly and that this activity and selectivity can be kept at high values for a very long time.

However, as a result of further intensive studies on the above method, the present inventors found that 4-by-4 dimerization of propylene was achieved by an entirely unexpected method.
- It was discovered that the production of methyl-1-pentene could be improved and the present invention was completed.

Alkali metals or organic alkali metal compounds usually decompose and lose their catalytic activity when they come into contact with water, alcohol, oxygen, etc.
Contact with them is avoided. However, the present inventors found that the compound represented by formula (1) above was used as a carrier for the reaction catalyst, and in some cases, an excessive amount of potassium carbonate, which was used as a raw material for producing the carrier, was mixed in the compound without reacting. A material in which at least one element or compound selected from the group of sodium, potassium, sodium amide, and potassium amide is supported on the material, or a material that has been hydrogen-treated in advance, and a patent application for these When an alcohol having 1 to 5 carbon atoms is brought into contact with a substance that has been brought into contact with oxygen by the method disclosed in No. 58-203508, surprisingly, the catalytic activity is deactivated. On the contrary, depending on the amount of alcohol brought into contact, the activity of the dimerization reaction and the selectivity of 4-methyl-1-pentene may improve, or the selection of 4-methyl-1-pentene may decrease, although the activity may decrease slightly. We found that the performance was significantly improved.

When dimerizing propylene using an alkali metal as a catalyst, the aforementioned Japanese Patent Publication No. 38-8701
Attempts have been made to increase the activity of catalysts by adding small amounts of alcohols, acids, aldehydes, etc. having 8 or more carbon atoms to alkali metals. However, the method discovered and perfected by the inventors is essentially different from this. That is, among the alcohols having 1 to 7 carbon atoms which are said to be ineffective in the above patent, in the present invention, the alcohol having 1 to 5 carbon atoms is used in an amount equivalent to that described in the examples of the patent. When used, not only the selectivity improves but also the activity significantly increases, but if an alcohol with 8 or more carbon atoms, which is considered effective in the patent, is used, both the activity and the selectivity decrease. Put it away. Furthermore, even when an alcohol containing 1 to 5 carbon atoms was applied to a known supported catalyst system in which sodium metal was supported on potassium carbonate, there was no effect at all, and the activity was only significantly reduced. It was hot. Therefore, in the present catalyst system, it is thought that the compound represented by the formula (1) has some kind of interaction with the alcohol to provide a new reaction site.

The method for producing 4-methyl-1-pentene of the present invention includes the following formula (1) K ₂ O・xAl ₂ O ₃ ...(1) Compound represented by (However, in the above formula, x is
At least one element or compound selected from the group consisting of sodium, potassium, sodium amide, and potassium amide is supported on a carrier whose main component is 0.5≦x≦11. After hydrogen treatment and/or oxygen treatment if desired,
It is characterized by using the alcohol in contact with No. 5 as a catalyst.

The compound represented by the above formula (1) used as the main component of the carrier in the method of the present invention can be obtained, for example, by the following method. That is,
KOH, KOR ¹ (R ¹ is at least one selected from C ₁ to C ₂₀ linear or branched aliphatic hydrocarbon residues, C ₆ to _{C 30} aryl groups, and aralkyl groups), KHCO ₃ , K ₂ CO ₃ (including those containing crystal water), KH, KR ² (R ² is a C ₁ to C ₂₀ linear or branched aliphatic hydrocarbon residue, a C ₆ to C ₃₀ aryl and at least one potassium-containing compound such as aralkyl group or aralkyl group), and alumina hydrate such as hydrogillite, vialite, boehmite, diaspor, α- and γ-alumina. ,Al
(OR ³ ) (R ³ is a mixture of at least one selected from C ₁ to C ₂₀ linear or branched aliphatic hydrocarbon residues, C ₆ to C ₃₀ aryl groups, or aralkyl groups) ) and at least one kind of aluminum-containing compound such as
Preferably, it is obtained by reacting at a temperature of 500 to 1500° C. in the presence or absence of air, nitrogen, etc. for 1 to 20 hours. In the compound represented by formula (1), x preferably takes a value in the range of 1≦x≦5.

The compound constituting this carrier is composed of K ₂ O and Al ₂ O ₃ , but this is a convenient representation of the composition of the carrier produced when the charging composition of the raw reagent changes. However, the compounds of these constituent elements do not exist as they are, but mainly as a double oxide. Therefore, simply mixing K ₂ O and Al ₂ O ₃ is a completely different type of carrier, and it is unlikely that the improvement in activity and selectivity expected when using the above carrier will be achieved. Can not.

When potassium carbonate is used as a potassium-containing compound that is a raw material for the catalyst support used in the method of the present invention, even if potassium carbonate is used so that x < 0.5, A carrier having the same improvement effect as when x in the compound is 0.5≦x≦11 can be obtained. That is, when potassium carbonate is used, an excess amount of potassium carbonate remains unreacted in the carrier, but the compound represented by formula (1) above and potassium carbonate can be handled in exactly the same way. It is something. In other words, as the carrier for the catalyst used in the method of the present invention, the compound represented by the above formula (1) may be used alone, or the support may be manufactured using the compound represented by the above formula (1) as a main component. A small amount of unreacted potassium carbonate used as a raw material may also be present. In this case, the remaining amount of potassium carbonate is calculated using the above formula.
It is preferably 30% by weight or less of the compound represented by (1).

In conventional catalysts for producing 4-methyl-1-pentene, the amount of sodium or potassium supported on the carrier is less than 5wt% because the carrier itself is inert or has a small porosity. , usually about 1 to 3 wt%. If these carriers
If you try to support more than 5wt% of sodium or potassium, these alkali metals will adhere to the surface of the carrier in a muddy form, causing the catalyst to coagulate into lumps, making it difficult to handle industrially. Not only was this difficult, but the dimerization activity was often extremely reduced. Furthermore, in order to adopt a fixed bed continuous flow method as a dimerization reaction method, it is necessary to make the catalyst into a pellet shape, but conventionally, the catalyst carrier for producing 4-methyl-1-pentene was Potassium carbonate, which is used as a raw material, does not have caking properties, so it was not possible to pelletize it. Therefore, in many of the known catalysts, pellets are manufactured using graphite or the like as a binder, and sodium or potassium is supported on the pellets. However, such pellets also have the disadvantage of short catalyst life because they have low mechanical strength and tend to disintegrate during use. On the other hand, the compound represented by formula (1), which is the carrier used in the method of the present invention, can absorb and support large amounts of sodium, potassium, their hydrides, amides, etc. very quickly. It maintains a very good dispersion state and is an excellent catalyst precursor either as it is or after being treated with hydrogen or oxygen if desired. By straining, a catalyst can be formed that provides higher activity and selectivity in the propylene dimerization reaction.

As mentioned above, this catalyst system has the following characteristics: the catalyst has good dispersibility and does not aggregate, has high activity and selectivity, and has almost no induction period at the start of the reaction. ,
It is very suitable for fully mixed mode reactions in which the catalyst is introduced continuously with the propylene into a tank reactor.

In addition, unlike potassium carbonate, the compound represented by formula (1), which is the main component of the carrier used in the method of the present invention, is formed by molding a kneaded product of the above-mentioned raw materials by a known method such as extrusion molding or compression molding. By then firing it, it is possible to make pellets with very high strength. The pellet-shaped carrier containing the compound of formula (1) as its main component absorbs and supports large amounts of sodium, potassium, their hydrides, amides, etc. very quickly, just like the powdered carrier. can do. Therefore, this product is an excellent catalyst precursor either as it is or after being subjected to hydrogen treatment or oxygen treatment if desired. In order to achieve high activity and selectivity in the dimerization reaction of propylene without reducing pellet strength, the catalyst is 4-methylpho-1 using a fixed bed continuous flow system.
- Ideal for the production of pentene.

The shape of the carrier used in the method of the present invention can be selected from any shape, such as a fine powder, a sphere of about 10 mm, or a columnar shape, depending on the reaction mode, the shape and capacity of the reactor, and the like. These can be produced by crushing and classifying the lumps of the compound represented by formula (1) obtained after firing the carrier raw material, or by kneading the raw materials and pelletizing them by extrusion molding, compression molding, etc., and then firing them. , can be manufactured in any desired shape and size.

The method for supporting sodium and/or potassium on the carrier described above can be carried out in exactly the same manner whether the carrier is a powder or a pellet. A method of stirring and mixing the sodium and/or potassium, a method of depositing sodium and/or potassium vapor on the carrier, etc. can be adopted. In addition, as a method for supporting sodium amide or potassium amide, the carrier is immersed in an ammonia solution of sodium amide or potassium amide by dissolving sodium or potassium in liquefied ammonia.
A common method is to fully impregnate the material and then evaporate the ammonia to support the material.

The amount of sodium, potassium, sodium amide, potassium amide, etc. supported on the carrier is preferably 0.1 to 20 wt% in terms of sodium atoms and/or potassium atoms. Even at a very high supported amount of 20 wt%, there are almost no tars or resinous by-products, and since the supported amount can be increased, there is no possibility of moisture or other substances entering the reaction system. Shows strong resistance to impurities,
High activity and selectivity can be maintained for very long periods of time. Of course, even if the amount supported is as low as 0.1 to 1 wt%, the activity will only decrease slightly and no particular problem will arise in carrying out the method of the present invention. Generally, it is preferable to use one supported in an amount of about 1 to 15 wt%.

The product obtained in this way includes the catalyst used in the method of JP-A-57-126426 mentioned above, and it already has catalytic activity for the dimerization reaction of propylene. . However, in the method of the present invention, these are treated as catalyst precursors. Prior to the alcohol treatment, the catalyst precursor can be made into a good catalyst precursor by, if desired, being treated with hydrogen at a temperature range of 150 to 400° C. and a pressure of up to 100 Kg/cm ² for 0.5 to 10 hours. be able to. Furthermore, a patent application was filed in 1982 for products that were not subjected to hydrogen treatment or those that were subjected to hydrogen treatment.
-203508, which has been brought into contact with oxygen, can also be used as a good catalyst precursor.

The alcohol having 1 to 5 carbon atoms that acts on the catalyst precursor thus obtained may be a saturated alcohol or an unsaturated alcohol, and specific examples include methanol, ethanol, n-propanol, isopropanol, and n-butyl. alcohol,
sec-butyl alcohol, isobutyl alcohol,
Examples include t-butyl alcohol, pentanol, allyl alcohol, and methallyl alcohol. Among these alcohols, methanol, ethanol, isopropanol, and especially ethanol are preferred.

As a method for causing alcohol to act on the catalyst precursor obtained in this way, regardless of whether the precursor is in the form of powder or pellets, aliphatic carbonization that does not react with alkali metals is possible. It can be applied by diluting alcohol with a liquid such as hydrogen or a gas such as an inert gas and bringing it into contact. However, in this method, sodium, potassium, sodium amide, potassium amide, or their hydrides (hereinafter referred to as
Since the reactivity of these metals (abbreviated as alkali metals) is extremely high, measures such as lowering the alcohol concentration sufficiently and stirring sufficiently to prevent localized excessive reactions with alcohol are required. Care must be taken to ensure uniform alcohol treatment. Diluents used in this case include saturated aliphatic hydrocarbons having 6 or more carbon atoms such as hexane, heptane, octane, and dodecane;
Alternatively, an inert gas such as nitrogen, helium, or argon is preferable. The concentration of alcohol at that time is
The appropriate amount is 0.001 to 5.0% by volume, and the treatment temperature is preferably in the range of -20 to 200°C, preferably 0 to 100°C.

In the method of the present invention, the amount of alcohol contacted with the catalyst precursor to prepare the catalyst is:
A compound represented by the formula (1) K ₂ O・xAl ₂ O ₃ (1) (However, in the above formula, x is
0.5 for alkali metals supported on a carrier whose main component is 0.5≦x≦11)
It ranges from 1 to 80 mol%, preferably from 1 to 50 mol%. If the amount of alcohol in the contact treatment is less than 0.5 mol %, the effect of the contact treatment with alcohol according to the present invention cannot be sufficiently exhibited. On the other hand, when the amount of alcohol catalytically treated exceeds 80 mol%, the selectivity remains high in the dimerization reaction, but the activity decreases and the catalyst life becomes short, resulting in an uneconomical process. Become something.

According to the method of the present invention using a catalyst treated with alcohol as described above, depending on the amount of alcohol treated, the activity of propylene dimerization and 4-
The selectivity for methyl-1-pentene is significantly improved. The reason for this is not clear so far, but
This is probably because the alcohol treatment changes the electronic state around the active sites of alkali metals on the carrier, restricting the coordination of propylene, making dimerization more likely to occur, and isomerization less likely to occur. Dew.

Another important feature of the method of the present invention is that when the reactor is charged with fresh catalyst and propylene is introduced to start the reaction, there is almost no induction period before the reaction starts. It is. It has been known that in conventional catalyst systems, the induction period can be as short as 10 to 15 hours, and as long as several days or more.

In carrying out the propylene dimerization reaction by the method of the present invention, various catalytic reaction modes are possible, including batch type using an autoclave,
A semi-batch type or a complete mixing tank type continuous reaction method in which the catalyst and the raw material propylene are continuously supplied to an autoclave, a fixed bed type continuous reaction method in which the catalyst is packed in a reactor and the raw material propylene is circulated therein, etc. can be adopted.

Further, suitable reaction conditions for the propylene dimerization reaction of the present invention include a temperature range of 100 to 250°C, preferably 140 to 180°C, and a suitable pressure range of 20 to 250°C.
~200Kg/ ^cm2 .

When using an autoclave, there is no particular restriction on the amount of catalyst to be used relative to the raw material propylene, but a range of 0.5 to 20 wt% is practically preferred. In addition,
The amount of catalyst used refers to the total amount of the carrier and supported alkali metals.

Further, the reaction time (in case of batch type or semi-batch type) or residence time (in case of continuous type) is preferably in the range of 1 to 10 hours. In the fixed bed continuous method, the liquid hourly space velocity (LHSV) is 0.1 to 10 (V/
A range of V·hr) is preferable.

The propylene used in the reaction in the method of the present invention does not necessarily have to be of high purity, but other olefins, diolefins, water, air, carbon dioxide gas, etc. are removed to the extent normally industrially possible. It is preferable to use a In addition, ethane, propane,
It is better not to include saturated hydrocarbons such as butane, but there is no problem if they are included.

In carrying out the propylene dimerization reaction by the method of the present invention, various catalytic reaction modes are possible, including batch type using an autoclave,
A semi-batch type or a complete mixing tank type continuous reaction method in which the catalyst and the raw material propylene are continuously supplied to an autoclave, a fixed bed type continuous reaction method in which the catalyst is packed in a reactor and the raw material propylene is circulated therein, etc. can be adopted.

In any of these reaction modes, it is possible to carry out the reaction using an aliphatic hydrocarbon such as heptane, octane, dodecane, a mixture thereof, or a compound that does not cause side reactions in this reaction as a solvent. It is.

The present invention will be explained in more detail below using Examples.

Example 1 66g of potassium hydroxide pellets (containing 15% moisture) are crushed into fine powder and boehmite 80g
g was mixed well, placed in an alumina crucible, and fired at 1200°C for 5 hours in an air atmosphere. After cooling, the fired product was taken out, placed in an alumina pot, and ground in a centrifugal ball mill for 2 hours.
A material finer than 60 mesh was used as a carrier. The K/Al ratio of this support was determined by atomic absorption spectrometry.
K/Al=0.98.

60g of this carrier was placed in a 3-necked flask containing 300ml.
The mixture was heated to 150° C. under a nitrogen gas atmosphere, and 6 g of sodium was added while stirring. After addition, increase the temperature to 200
℃ and continued stirring for 1 hour to uniformly support the catalyst precursor.

16 g of the catalyst precursor thus obtained was thoroughly dried and placed in a stainless steel autoclave with a capacity of 1000 ml which had been purged with nitrogen.
Add 100 ml of n-pentane containing 30 ml of ethanol.
Stir for a minute. Through this operation, an amount of ethanol corresponding to 10 mol% of the supported sodium was subjected to the contact treatment.

A propylene dimerization reaction was carried out using the catalyst thus obtained. That is, 150 g of propylene was placed in the autoclave and a reaction was carried out at 160° C. for 5 hours. After the reaction was completed, the autoclave was quenched with tap water to stop the reaction, and unreacted propylene was collected in a trap in a dry ice-methanol bath. Furthermore, the solvent, reaction products, etc. remaining in the reactor were recovered by vacuum distillation.
After evaporating the propylene previously collected in the trap in the recovered reaction solution, the remaining parts with a boiling point higher than the dimer were combined and coated with squalane.
Analysis by gas chromatography using a 50 m long glass capillary column revealed that the propylene reaction rate was 36% and the 4-methyl-1-pentene selectivity was 93%. Therefore, the activity per gram of this catalyst per hour is:
It was 0.675 (g-dimer/g-catalyst/hr) (description of units is omitted in the following examples).

Example 2 n-heptane containing 0.09% ethanol by weight
A propylene dimerization reaction was carried out under exactly the same conditions as in Example 1, except that 100 ml was used and the amount of ethanol treated as the catalyst precursor was 2 mol % of sodium. As a result of the analysis, the reaction rate of propylene was 42
%, the selectivity for 4-methyl-1-pentene was 93%, and the activity of the catalyst was 0.788.

Example 3 n-heptane with 2.14% ethanol by weight
A propylene dimerization reaction was carried out under exactly the same conditions as in Example 1, except that 100 ml was used and the amount of ethanol treated as the catalyst precursor was 50 mol % of sodium. As a result of analysis, the reaction rate of propylene was 29
%, the selectivity for 4-methyl-1-pentene was 92%, and the activity of the catalyst was 0.544.

Comparative Example 1 A propylene dimerization reaction was carried out under exactly the same conditions as in Example 1, except that the catalyst precursor was used as a catalyst without being subjected to ethanol treatment. As a result of the analysis, the reaction rate of propylene was 34%, 4
-Selectivity for methyl-1-pentene is 89%,
The activity of this catalyst was 0.638.

Example 4 (See Example 1 for the chemical reaction formula) Ethanol treatment was carried out in the same manner as in Example 1 using 16 g of a catalyst precursor in which 5 wt% of potassium was supported instead of sodium on the carrier used in Example 1. was carried out. The amount of ethanol contacted corresponded to 5 mol% of the supported sodium. Next, a propylene dimerization reaction was carried out in the same manner as in Example 1. As a result of the analysis, the reaction rate of propylene was 35%.
The selectivity for 4-methyl-1-pentene was 92% and the activity was 0.656.

Example 5 The treatment of the catalyst precursor was carried out using 300 ml of n-heptane containing 0.2% by weight of methanol instead of the n-heptane containing ethanol used in Example 1, and the reaction time was 3 hours. Except for the above, the propylene dimerization reaction was carried out under exactly the same conditions as in Example 1. The throughput of methanol corresponds to 20 mol% of the supported sodium. As a result of analysis, the reaction rate of propylene was 41%, 4-methyl-1
- The selectivity for pentene was 90% and the activity of the catalyst was 1.280.

Example 6 Example 1 except that the catalyst precursor throughput was carried out using 100 ml of n-heptane containing 0.28% by weight isopropyl alcohol instead of the n-heptane containing ethanol used in Example 1. A propylene dimerization reaction was carried out under exactly the same conditions.
The throughput of isopropyl alcohol corresponds to 5 mol% of the supported sodium. As a result of the analysis,
The reaction rate of propylene is 38%, the selectivity of 4-methyl-1-pentene is 92%, and the activity of this catalyst is
It was 0.713.

Example 7 Propylene dimerization was carried out under exactly the same conditions as in Example 1, except that 100 ml of n-heptane containing 0.82% by weight of isoamyl alcohol was used instead of the n-heptane containing ethanol used in Example 1. The reaction was carried out. The contact throughput of isoamyl alcohol corresponds to 10 mol% of the supported sodium. As a result of the analysis, the reaction rate of propylene was 33%, 4
- The selectivity of methyl-1-pentene is 90%,
The activity of this catalyst was 0.619.

Comparative Example 2 Propylene was diluted under exactly the same conditions as in Example 1, except that 100 ml of n-heptane containing 1.21% by weight of n-octanol was used instead of the n-heptane containing ethanol used in Example 1. A quantification reaction was performed. The contact throughput of n-octanol corresponds to 10 mol% of the supported sodium. As a result of analysis, the reaction rate of propylene was 18%, 4-methyl-1
- The selectivity for pentene was 37% and the activity of the catalyst was 0.338. This result shows that the activity and selectivity are significantly inferior compared to Examples 1 to 7.

Example 8 200 g of potassium hydrogen carbonate and 202 g of γ-alumina were thoroughly mixed and fired at 1000° C. for 7 hours to produce a carrier. Add 1.5 g of sodium to 15 g of this carrier,
Support was carried out by stirring vigorously at 200° C. for 1 hour. The entire amount of the obtained sodium carrier was placed in a stainless steel autoclave with an internal capacity of 1, and n was added as a solvent.
- 100 ml of heptane was added, the temperature was raised to 160°C, and the mixture was pressurized to 70 kg/cm ² G with hydrogen and stirred for 3 hours. After cooling and releasing residual hydrogen, 50 ml of n-heptane containing 0.88% by weight of ethanol was added and stirred for 30 minutes. By this operation, the supported sodium
An amount of ethanol corresponding to 10 mol% was contacted.

Add 150g of propylene to this autoclave,
The temperature was raised to 160°C again and reaction was carried out for 5 hours. As a result of analysis, the reaction rate of propylene was 37%, 4-methyl-
The selectivity for 1-pentene was 92% and the activity of this catalyst was 0.673.

Example 9 112g of potassium t-butoxy and aluminum
When 246 g of sec-butoxide is mixed in 200 ml of t-butanol at 70°C under a nitrogen atmosphere, the art complex K [Al(OBu ^t ) (OBu ^sec ) ₃ ] is obtained.
was precipitated as a white precipitate. After distilling off the solvent t-butanol under reduced pressure, the precipitate was dissolved in a nitrogen stream.
Preliminary firing was performed at 500° C. for 4 hours to decompose all organic residues. Thereafter, the temperature was raised to 1200°C and baking was continued for an additional 3 hours.

6 g of sodium was added to 60 g of the carrier thus obtained under a nitrogen stream, and the mixture was vigorously stirred at 200° C. for 2 hours to support sodium.

16 g of the catalyst precursor thus obtained was thoroughly dried and placed in a stainless steel autoclave with a capacity of 1000 ml which had been purged with nitrogen, and 100 ml of n-heptane was added thereto as a dispersion medium. The valve of this autoclave was connected to a U-shaped mercury manometer, and air dried with a molecular sieve 3A was forced into the autoclave until the mercury column reached 150 mmHg. The autoclave was treated with oxygen while rotating the stirrer until the manometer reading fell to 130 mmHg, at which point the air inside the autoclave was released and replaced with nitrogen gas. Through this operation, an amount of oxygen corresponding to 1.5 mol% of the supported sodium was contacted. next
50 ml of n-heptane was added to 0.45% by weight ethanol and stirred for 30 minutes. Through this operation, an amount of ethanol corresponding to 5 mol% of the supported sodium was contacted.

Add 150g of propylene to this autoclave,
The reaction was carried out at 160°C for 5 hours. As a result of analysis, the reaction rate of propylene was 39%, the selectivity of 4-methyl-1-pentene was 93%, and the activity of this catalyst was
It was 0.731.

Example 10 100g of anhydrous potassium carbonate and aluminum hydroxide
78.0g, each with a particle size smaller than 16mesh, mixed to be sufficiently uniform, and heated to 1100℃.
The carrier was prepared by firing at a temperature of 5 hours. The K/Al ratio of this support was determined by atomic absorption spectrometry.
Al=1.45. In addition, when calculated from the amount of carbon dioxide gas generated by acid decomposition of the formed carrier, 32g of unreacted potassium carbonate remained, and K ₂ O.
It was found that x=0.98 for xAl ₂ O ₃ .

15.0 g of this carrier and 1.0 g of sodium were placed in a stainless steel autoclave, and 30 g of liquefied ammonia was pressurized into the autoclave. After stirring at room temperature for 2 hours, ammonia and hydrogen produced by the reaction were released. Next, 100 ml of n-heptane containing 0.20% by weight of isopropyl alcohol was added to the autoclave and stirred for 30 minutes. With this operation,
This means that an amount of isopropyl alcohol corresponding to 5 mol % of the supported sodium amide was subjected to the contact treatment.

A propylene dimerization reaction was carried out using the catalyst thus obtained. That is, 150 g of propylene was placed in the autoclave and a reaction was carried out at 150° C. for 5 hours. Post-processed in the same manner as in Example 1,
According to analysis, the reaction rate of propylene was 19%, 4-
The selectivity for methyl-1-pentene was 92% and the activity was 0.356.

Example 11 (See Example 10 for chemical reaction formula) Potassium amide was supported on the carrier obtained in Example 10 by using potassium instead of sodium. The amount of potassium used, the conditions for amide formation, etc. were exactly the same as in Example 10. Using the thus obtained potassium amide-supported material, it was treated with ethanol in the same manner as in Example 10, and an amount of ethanol corresponding to 20 mol % of the supported potassium amide was subjected to contact treatment.

Using this catalyst, the temperature was 160°C in the same manner as in Example 6.
The reaction was carried out for 5 hours. As a result of analysis, the conversion rate of propylene was 32%, the selectivity of 4-methyl-1-pentene was 92%, and the activity of this catalyst was 0.600.

Comparative Example 3 2 g of sodium was added under a nitrogen atmosphere to 100 g of potassium carbonate dried at 500° C. for 5 hours, and the mixture was vigorously stirred at 200° C. to support sodium.

36 g of this catalyst was placed in a stainless steel autoclave with an internal capacity of 1 under a nitrogen atmosphere, and propylene
150 g was added together with 100 ml of n-heptane as a solvent, and the reaction was carried out at 160° C. for 20 hours. As a result of the analysis,
The reaction rate of propylene is 43%, the selectivity of 4-methyl-1-pentene is 75%, and the activity of this catalyst is
It was 0.090.

Comparative Example 4 Add 2 sodium to the potassium carbonate obtained in Comparative Example 3.
Using the weight% supported catalyst as a catalyst precursor,
28 g of this precursor was thoroughly dried and placed in a stainless steel autoclave with an internal capacity of 1, which had been purged with nitrogen.
100 ml of heptane was added and stirred for 30 minutes. Through this operation, an amount of ethanol corresponding to 2 mol % of the supported sodium was subjected to the contact treatment.
A propylene dimerization reaction was carried out using the catalyst thus obtained. That is, 150 g of propylene was placed in the autoclave and a reaction was carried out at 160° C. for 3 hours. As a result of the analysis, the reaction rate of propylene was 35%, and the selectivity of 4-methyl-1-pentene was
77%, and the activity of this catalyst was 0.062.

As is clear from comparison with Comparative Example 3, when the carrier is changed to potassium carbonate, no effect of the alcohol contact treatment is observed, and rather the activity is reduced.

Example 12 138g of anhydrous potassium carbonate and aluminum hydroxide
A small amount of water was added to 156 g, kneaded, and formed into pellets with a diameter of 1.6 mm and a length of 5 to 8 mm using an extruder. This was calcined at 1000°C for 5 hours to obtain a carrier. Sodium was added to the entire amount of this carrier at 200° C. to give a concentration of 10 wt % under a nitrogen atmosphere, and was sufficiently stirred for 2 hours to support the carrier. The temperature was further raised to 400°C and heating was continued for an additional 2 hours. 500 ml of 100 g of the sodium-supported pellets obtained in this way.
The mixture was placed in a large volume glass flask and 300 ml of n-heptane containing 0.98% by weight of ethanol was added thereto and stirred for 30 minutes to effect contact treatment with ethanol. The amount of ethanol treated was 10 mol% of sodium. Using the catalyst thus obtained, propylene was dimerized by a fixed bed continuous flow reaction method.
In other words, propylene was heated at a liquid hourly space velocity (LHSV) of 2.0hr ^-1 while maintaining the reaction temperature at 150℃ and pressure at 90Kg/ ^cm2 .
The reaction was carried out while introducing the mixture. The propylene reaction rate became steady and reached 39% in 20 hours.
The content of 4-methyl-1-pentene in the product is
It was 93%. Although the reaction was continued, the half-life of the activity, that is, the time required for the propylene conversion to decrease by half from its maximum value, exceeded 1,500 hours.

Claims (1)

[Claims] 1. In a method for producing 4-methyl-1-pentene by dimerization reaction of propylene, the following formula (1) K ₂ O.xAl ₂ O ₃ ...(1) The compound shown (however, in the above formula, x is
At least one element or compound selected from the group consisting of sodium, potassium, sodium amide, and potassium amide is supported on a carrier whose main component is 0.5≦x≦11. After optional hydrogen treatment and/or oxygen treatment, the
A method for producing 4-methyl-1-pentene, the method comprising using as a catalyst a product brought into contact with an alcohol. 2. Claim 1, wherein the carrier consists essentially only of the compound represented by the formula (1).
The method described in section. 3. The method according to claim 1, wherein the carrier comprises a mixture of the compound represented by formula (1) and a small amount of potassium carbonate.