JPH0333135B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a novel method 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.

[Conventional technology]

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

Furthermore, propylene was dimerized using a catalyst in which an alkali metal was supported on a carrier, and 4-methyl-1
- It is also known that it is possible to obtain 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 dissolves. There were cases where the activity was lost. 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.

Furthermore, 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. %below,
Usually it was about 1 to 3 wt%. If you try to support 5wt% or more of sodium or potassium on these carriers, these alkali metals will adhere to the carrier surface in a muddy form, causing the catalyst to coagulate into lumps and be 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, 4-methyl-1-
Potassium carbonate, which is used as a catalyst carrier for the production of pentene, does not have caking properties, so it has not been 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.

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.
The present inventors have discovered that the method for producing -methyl-1-pentene can be further improved in terms of selectivity, and have completed the present invention.

[Summary of the invention]

Alkali metals or organic alkali metal compounds usually react with water, oxygen, and oxygen-containing compounds such as alcohols and esters, and their catalytic activity is lost, so contact with these substances 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 Surprisingly, when a specific ester is brought into contact with a substance that has been catalytically treated with oxygen by the method disclosed in No. 58-203508, its catalytic activity is not deactivated, but rather changes depending on the amount of ester brought into contact with it. found that the dimerization activity and selectivity for 4-methyl-1-pentene were improved, or that the selectivity for 4-methyl-1-pentene was significantly improved, although the activity was slightly decreased.

[Problem that the invention seeks to solve]

The object of the present invention is to improve the drawbacks of the previously known methods and catalysts as described above, and to use a catalyst with improved propylene dimerization activity and 4-methyl-1-pentene selectivity. Methyl-
An object of the present invention is to provide a method for producing 1-pentene.

[Means for solving problems]

That is, the method for producing 4-methyl-1-pentene of the present invention involves a dimerization reaction of propylene,
In the method for producing 4-methyl-1-pentene, a compound represented by the following formula (1) K ₂ O・xAl ₂ O ₃ ...(1) (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 as desired, the ester represented by the following formula (2) R ¹ COOR ² ... (2) (However, R ¹ is a C ₁ to C ₁₅ chain or cyclic aliphatic hydrocarbon residue or a C ₆ to C ₂₀ aryl group or aralkyl group, R ² represents a C ₁ to _{C 6} chain or cyclic aliphatic hydrocarbon residue). It is characterized by being used as

[Preferred mode for carrying out the invention]

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 ³ (R ³ represents a C ₁ to C ₂₀ linear or branched aliphatic hydrocarbon residue or a C ₆ to _{C 30} aryl group or aralkyl group), KHCO ₃ ,
K ₂ CO ₃ (including those containing water of crystallization), KH,
at least one potassium-containing compound such as KR ⁴ (R ⁴ represents a C ₁ to _{C 20} linear or branched aliphatic hydrocarbon residue or a C ₆ to C ₃₀ aryl group or aralkyl group); Alumina hydrates such as gillite, vialite, boehmite, diaspor, α- and γ-alumina, Al
(OR ⁵ ) ₃ (R ⁵ represents at least one selected from a C ₁ to C ₂₀ linear or branched aliphatic hydrocarbon residue and a C ₆ to C ₃₀ aryl group or aralkyl group) and at least one aluminum-containing compound, such as K/Al ratio, is mixed with the predetermined K/Al ratio of It can be obtained by reacting for 1 to 20 hours in the presence or absence of the compound. 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, the compound represented by formula (1) A carrier having the same improvement effect as when x in 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 a 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 compound represented by the above formula (1) may be the main component, with a small amount of unreacted potassium carbonate used as a raw material for manufacturing the carrier mixed in. It's okay to be hot. In this case, the residual amount of potassium carbonate is preferably 30% by weight or less of the compound represented by formula (1) above.

The above formula which is a carrier used in the method of the present invention
The compound shown in (1) can absorb and support large amounts of sodium, potassium, their hydrides, amides, etc. very quickly, so it maintains a very good dispersion state and can be used as is or as desired. Those subjected to hydrogen treatment or oxygen treatment are also very excellent catalyst precursors. 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 strength of the carrier mainly composed of the compound of the formula (1) obtained in the form of pellets can also be improved by contact treatment with the ester of the formula (2) according to the method of the present invention. Since high activity and selectivity are achieved in the dimerization reaction of propylene without deterioration, it is optimal for the production of 4-methyl-1-pentene by a fixed bed continuous flow system.

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 evaporate and support ammonia after sufficient impregnation.

The amount of catalytically active species sodium, potassium, sodium amide, and potassium amide (hereinafter referred to as alkali metals) supported on the carrier is determined by the amount of sodium atoms and/or potassium amide of the alkali metals.
Alternatively, it is preferably 0.1 to 20 wt% in terms of potassium atoms. Even at a very high supported amount of 20wt%, there are almost no side effects of tar or resinous substances, and since the supported amount can be increased further, there is no need to worry about moisture entering the reaction system. It also shows strong resistance to other impurities and can maintain high activity and selectivity for a very long period of time. Of course, even if the supported amount is as low as 0.1 to 1 wt%, the activity will only decrease slightly, and no particular problem will occur to the implementation of 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. The catalyst precursor may optionally be treated with e.g.
At pressures up to 100Kg/ ^cm2 at temperatures ranging from 150 to 400℃
A good catalyst precursor can also be obtained by hydrogen treatment for 0.5 to 10 hours. Furthermore, those without hydrogen treatment or those subjected to hydrogen treatment and brought into contact with oxygen by the method disclosed in Japanese Patent Application No. 58-203508 can also be used as good catalyst precursors.

The ester represented by the formula (2) that is applied to the catalyst precursor thus obtained may be a saturated ester or an unsaturated ester, and specific examples thereof include methyl formate, ethyl formate, ethyl acetate, and acetic acid. Examples include isopropyl, pentyl acetate, methyl propionate, ethyl propionate, butyl butyrate, ethyl acrylate, ethyl methacrylate, methyl benzoate, and ethyl benzoate.

Regardless of whether the catalyst precursor is in the form of powder or pellets, the method of applying the above-mentioned esters to the catalyst precursor is to use an aliphatic hydrocarbon that does not react with alkali metals. This can be carried out by diluting the ester with a liquid such as this or a gas such as an inert gas and bringing it into contact with the diluted ester. but,
Since the reactivity of the alkali metals supported on the carrier is very high in this method, the ester concentration must be kept sufficiently low and sufficient stirring must be carried out to prevent local reaction with excessive amounts of ester. Care must be taken to ensure uniform ester 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 ester in this case is suitably 0.005 to 20% by volume, and the treatment temperature is suitably in the range of 0 to 300°C, preferably 20 to 200°C.

In the method of the present invention, the amount of ester to be brought into contact with the catalyst precursor in order to prepare the catalyst is determined by the amount of the ester that is brought into contact with the catalyst precursor. In contrast, the amount is in the range of 0.5 to 80 mol%, preferably 1 to 50 mol%. When the amount of ester treated is less than 0.5 mol %, the effect of the contact treatment with ester according to the present invention cannot be sufficiently exhibited. On the other hand, when the amount of contact with the ester 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 effect. Become something.

According to the method of the present invention using a catalyst treated with ester as described above, the propylene dimerization activity and the selectivity of 4-methyl-1-pentene can be significantly improved depending on the amount of ester treated. The reason for this is not clear so far, but perhaps the ester treatment changes the electronic state around the active sites made of alkali metals on the carrier, restricting the coordination of propylene and making it easier to dimerize. It is also assumed that this is because isomerization is becoming less likely to occur.

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. . In the catalyst systems known so far, even when the induction period is short,
It was known to last for 10 to 15 hours, or even 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.

In any of these reaction modes, it is not 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 a side reaction in this reaction as a solvent. It is possible.

Further, suitable reaction conditions for the propylene dimerization reaction of the present invention are 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 an autoclave is used, there is no particular restriction on the amount of catalyst used relative to the raw material propylene, but a range of 0.5 to 20% by weight is practically preferred. In addition,
The amount of catalyst used refers to the total amount of the carrier and supported alkali metals.

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

The raw material propylene used in the reaction does not necessarily have to be of high purity, but it should be one from which other olefins, diolefins, water, air, carbon dioxide, etc. have been removed to the extent that is normally industrially possible. It is preferable to use Although it is better not to include saturated hydrocarbons such as ethane, propane, and butane, there is no problem if they are included.

〔Effect of the invention〕

According to the method for producing 4-methyl-1-pentene of the present invention, the induction period is short, the propylene dimerization activity is high, the selectivity for 4-methyl-1-pentene is high, and the catalyst life is long. Get results.

[Example of the present invention]

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

Example 1 KOH + boehmite → K ₂ O・xAl ₂ O (x=0.98) Na --→ Na-supported K ₂ O・xAl ₂ O ₃ ethyl acetate --------→ Cat.-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 300ml three-necked flask.
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 1000 ml stainless steel autoclave that had been purged with nitrogen, and 100 ml of n-heptane containing 0.83% by weight of ethyl acetate was added thereto. The mixture was stirred at 100°C for 1 hour. After cooling the autoclave, a portion of the liquid was sampled and analyzed by gas chromatography, and it was found that almost all of the charged ethyl acetate had been consumed, equivalent to 10 mol% of the sodium supported by this operation. of ethyl acetate was contacted.

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, the recovered reaction solution was combined with the remaining portion having a boiling point higher than that of the dimer, and was coated with squalane.
Analysis by gas chromatography using a m-long glass capillary column revealed that
The propylene reaction rate was 37%, and the 4-methyl-
The selectivity for 1-pentene was 93%. Therefore, the activity per gram of this catalyst per hour is 0.694
(g-dimer/g-catalyst/hr) (description of units will be omitted in the following examples).

Example 2 n-heptane with 0.17% ethyl acetate 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 ethyl acetate treated as a catalyst precursor was 2 mol % of sodium. As a result of analysis, the reaction rate of propylene is 35
%, the selectivity for 4-methyl-1-pentene was 93%, and the activity of this catalyst was 0.656.

Example 3 n-heptane with 4.13% ethyl acetate 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 ethyl acetate treated as a catalyst precursor was 50 mol% of sodium. As a result of the analysis, the reaction rate of propylene was 32
%, the selectivity for 4-methyl-1-pentene was 92%, and the activity of this catalyst was 0.600.

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 ethyl acetate 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) Ethyl acetate was prepared 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. Processing was carried out. The amount of ethyl acetate contacted corresponded to 5 mol% of the supported potassium. 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 36%, 4-
The selectivity for methyl-1-pentene is 92%, and the activity is
It was 0.675.

Example 5 The catalyst precursor was treated using 300 ml of n-heptane containing 0.46% by weight of methyl acetate instead of the n-heptane containing ethyl acetate used in Example 1, and the reaction time was 3 hours. A propylene dimerization reaction was carried out under exactly the same conditions as in Example 1, except for the following. The contact processing amount of methyl acetate is
This corresponded to 20 mol% of the supported sodium. As a result of analysis, the conversion rate of propylene was 42%, the selectivity of 4-methyl-1-pentene was 91%, and the activity of this catalyst was 1.313.

Example 6 Example 1 was repeated, except that the treatment of the catalyst precursor was carried out using 100 ml of n-heptane containing 0.64% by weight of cyclohexyl acetate instead of the n-heptane containing ethyl acetate used in Example 1. A propylene dimerization reaction was carried out under exactly the same conditions. The contact throughput of cyclohexyl acetate corresponded to 5 mol% of the supported sodium. As a result of analysis, the reaction rate of propylene was 40%, the selectivity of 4-methyl-1-pentene was 92%, and the activity of this catalyst was 0.750.
It was hot.

Example 7 N-heptane containing ethyl acetate used in Example 1 was replaced with n-heptane containing 1.41% by weight of ethyl benzoate.
- A propylene dimerization reaction was carried out under exactly the same conditions as in Example 1, except that the catalyst precursor was treated with 100 ml of heptane. The catalytic treatment amount of ethyl benzoate corresponded to 10 mol% of the supported sodium. As a result of the analysis, the reaction rate of propylene was 31%, and the selectivity of 4-methyl-1-pentene was 90.
%, and the activity of this catalyst was 0.581.

Comparative Example 2 Example 2, except that instead of the n-heptane containing ethyl acetate used in Example 1, the treatment of the catalyst precursor was carried out using 100 ml of n-heptane containing 1.62% by weight of n-octyl acetate. A propylene dimerization reaction was carried out under exactly the same conditions as in Example 1. The contact throughput of n-octyl acetate is
It corresponded to 10 mol%. As a result of analysis, the reaction rate of propylene was 20%, the selectivity of 4-methyl-1-pentene was 44%, and the activity of this catalyst was 0.400. This result showed that the activity and selectivity were significantly inferior compared to Examples 1 to 7.

Example 8 KHCO ₃ +Al ₂ O ₃ →K ₂ O・xAl ₂ O ₃ (x=1.0) Na --→ Na-supported K ₂ O・xAl ₂ O ₃ H ₂ --→ Hydrogenated product ethyl acetate -- ――――→ Cat.-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,
The mixture was vigorously stirred at 200° C. for 1 hour to support it. 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.
- After adding 100 ml of heptane and raising the temperature to 160°C, 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 2.25% by weight of ethyl acetate was added, and the mixture was heated at 100℃ for 1 hour.
Stir for hours. Through this operation, an amount of ethyl acetate corresponding to 10 mol% of the supported sodium 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 93% and the activity of this catalyst was 0.673.

Example 9 t-BuOK+(sec-BuOK) ₃ Al →K[Al(OBu ^t )(OBu ^sec ) ₃ ] 2K[Al(OBu ^t )(OBu ^sec ) ₃ ] △ ―→ K ₂ O・Al ₂ O ₃ +4BuOBu K ₂ O・Al ₂ O ₃ Na ――→ Na-carrying K ₂ O・Al ₂ O ₃ O ₂ ――→ Ethyl acetate――――――→ Cat.−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 deposited 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 an internal 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 containing 0.83% by weight of ethyl acetate
was added and stirred at 100°C for 1 hour. Through this operation, an amount of ethyl acetate 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 propylene reaction rate was 40%, the 4-methyl-1-pentene selectivity was 93%, and the activity was 0.750.

Example 10 K ₂ CO ₃ +Al(OH) ₃ →K ₂ O・xAl ₂ O ₃ (x=0.98) 2Na+2NH ₃ →2NaNH ₂ +H ₂ K ₂ O・xAl ₂ O ₃ NaNH ₂ ――――――→ NaNH ₂ supported K ₂ O・xAl ₂ O ₃ Isopropyl formate――――――――――→ Cat.−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. Calculating 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. The autoclave was then charged with 100% n-heptane containing 0.28% by weight of isopropyl formate.
ml and stirred at 100°C for 1 hour. By this operation, an amount of isopropyl formate corresponding to 5 mol % of the supported sodium amide was subjected to 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. As a result of the analysis, the reaction rate of propylene was 21%, and the selectivity of 4-methyl-1-pentene was
The activity was 93% and 0.394.

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 product, it was treated with ethyl acetate in the same manner as in Example 10, and an amount of ethyl acetate corresponding to 20 mol % of the supported potassium amide was contacted with the product.

Using this catalyst, the temperature was 160°C in the same manner as in Example 1.
A propylene dimerization reaction was carried out for 5 hours. As a result of the analysis, the propylene reaction rate was 34%, the 4-methyl-1-pentene selectivity was 93%, and the activity was 0.638.

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

36g of this catalyst was heated to 1% in content under a nitrogen gas atmosphere.
The mixture was placed in a stainless steel autoclave, 150 g of propylene 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 analysis, the reaction rate of propylene was 43%, 4-methyl-
The selectivity for 1-pentene was 75% and the activity of this catalyst was 0.090.

Comparative Example 4 The potassium carbonate obtained in Comparative Example 3 with 2% by weight of sodium supported was used as a catalyst precursor, and 28 g of this precursor was thoroughly dried and placed in a stainless steel autoclave with an internal capacity of 1, which was purged with nitrogen. 100 ml of n-heptane containing 0.06% by weight of ethyl acetate was added thereto, and the mixture was stirred at 100° C. for 1 hour.
Through this operation, an amount of ethyl acetate corresponding to 2 mol % of the supported sodium was contacted.
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 30 hours. As a result of the analysis, the reaction rate of propylene was 32%, and the selectivity of 4-methyl-1-pentene was 77%.
%, and the activity was 0.057.

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

Example 12 K ₂ CO ₂ +Al(OH) ₃ →K ₂ O・xAl ₂ O ₃ (x=1.0) Na --→ Na-supported K ₂ O・xAl ₂ O ₃ Ethyl acetate --------→ Cat.−12 138g of anhydrous potassium carbonate and aluminum hydroxide
A small amount of water was added to 156 g, and the mixture was thoroughly 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 placed in an alumina crucible and fired at 1000°C for 5 hours in an air atmosphere to obtain a carrier. The entire amount of this carrier was heated to 200°C in a nitrogen gas atmosphere.
Sodium was added to the solution to give a concentration of 10% by weight, and the temperature was further raised to 400°C and heating continued for 2 hours.

Put 100 g of the sodium-supported pellets obtained in this way into a 500 ml glass flask,
n-heptane 300 containing 1.89% by weight ethyl acetate
ml was added, stirred at 100°C for 1 hour, and treated with ethyl acetate. Ethyl acetate processing amount is 10% of sodium
It was mol%. Using the catalyst thus obtained, a dimerization reaction of propylene was carried out by a fixed bed continuous flow reaction method. i.e. reaction temperature 150
The reaction was carried out while maintaining the temperature and pressure at 90 Kg/cm ² and introducing propylene at a liquid hourly space velocity (LHSV) of 2.0 hr ^-1 . The propylene reaction rate reached a steady state in 20 hours, reaching 41%. 4-methyl- in the product
The content of 1-pentene was 93%. Although the reaction was continued, the half-life of the activity, that is, the time it takes for the conversion rate of propylene to decrease by half from its highest value, was
It was over 1500 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 hydrogen treatment and/or oxygen treatment as desired, the ester represented by the following formula (2) R ¹ COOR ² ... (2) (However, R ¹ is a C ₁ to C ₁₅ chain or cyclic aliphatic hydrocarbon residue or a C ₆ to C ₂₀ aryl group or aralkyl group, R ² represents a C ₁ to _{C 6} chain or cyclic aliphatic hydrocarbon residue). A method for producing 4-methyl-1-pentene, characterized in that it is used as 4-methyl-1-pentene. 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.