JP2000264919A - Production of alpha-olefin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for the production of an α-olefin containing a linear α-olefin in high purity at high yield of a 6-10C α-olefin. SOLUTION: The objective α-olefin production process for getting an α-olefin- olefin having Poisson distribution comprises the 1st step to oligomerize ethylene to obtain an α-olefin having Schultz-Flory distribution and separate 1-butene, the 2nd step to perform the substitution reaction of 1-butene with triethylaluminum to obtain tributylaluminum and the 3rd step to perform the reaction of tributylaluminum with ethylene.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing an α-olefin, and more particularly, to a product distribution (a high yield of a linear α-olefin having 6 to 10 carbon atoms) corresponding to future demand. The present invention relates to a method for producing an α-olefin having high purity and containing a linear α-olefin.

[0002]

2. Description of the Related Art Linear α-olefins have a straight-chain molecular structure without branching and have 4 to 4 carbon atoms having a terminal double bond.
It is an oligomer of about 20 olefins. α-olefin, especially α-olefin containing linear α-olefin in high purity
Olefins are useful as modified monomers for polyolefins or as raw materials for synthetic lubricating oils, plasticizers and surfactants. In particular, those having about 6 to 10 carbon atoms are expected to grow in demand in the future.

As a method for producing an α-olefin, a method for oligomerizing ethylene is known, and there are methods for producing an α-olefin having a Schulz-Flory distribution and an α-olefin having a Poisson distribution. Methods for producing α-olefins having a Schulz-Flory distribution include a method using a zirconium-based complex catalyst and a one-step method using alkylaluminum. -Olefin can be obtained, but the distribution of obtained α-olefins is wide and the yield of α-olefins having 6 to 10 carbon atoms is low. In addition, when the distribution of the obtained α-olefin is relatively narrowed to increase the production of α-olefins having 10 or less carbon atoms, the production of α-olefins having 4 to 6 carbon atoms is extremely increased. Α- having 6 to 10 carbon atoms useful as a comonomer or synthetic lubricating oil raw material
Insufficient olefin yield.

On the other hand, as a method for producing an α-olefin having a Poisson distribution, there is a two-stage method (growth reaction-exchange reaction) using trialkylaluminum, which has 6 to 1 carbon atoms.
Although the yield of α-olefin of 0 is high, the purity of linear α-olefin is low. In order to obtain an α-olefin containing 6 to 10 carbon atoms with a high yield and a high purity and containing a linear α-olefin, an improved method using a zirconium-based catalyst (for example, JP-A-6-29367)
0, Japanese Patent Application Laid-Open No. 7-330634, Japanese Patent Application Laid-Open
Japanese Patent Application Laid-Open Nos. 2-218800 and 3-alkyl aluminum (JP-A-3-48630, JP-A-7-97344, etc.), but no satisfactory results have been obtained.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made from the above viewpoint, and has a high yield of α-olefins having 6 to 10 carbon atoms and a high purity of α-olefins containing linear α-olefins.
To provide a method for producing an α-olefin capable of obtaining an olefin.

[0006]

SUMMARY OF THE INVENTION The present inventors have achieved the above object effectively by combining a method for producing an α-olefin having a Schulz-Flory distribution with a method for producing an α-olefin having a Poisson distribution. It has been found that the present invention can be performed and the present invention has been completed. That is, the gist of the present invention is as follows. (1) In the first step, ethylene is oligomerized to obtain an α-olefin having a Schulz-Flory distribution to obtain 1-
Separating butene, in a second step, substituting the 1-butene with triethylaluminum to obtain tributylaluminum, and in a third step, reacting the tributylaluminum with ethylene to obtain an α-olefin having a Poisson distribution A method for producing an α-olefin, characterized by comprising: (2) The method for producing an α-olefin according to the above (1), wherein in the first step, ethylene is oligomerized using a zirconium-based complex catalyst. (3) In the third step, tributylaluminum is reacted with ethylene to obtain a higher trialkylaluminum, and then the higher trialkylaluminum is subjected to a substitution reaction with ethylene to obtain an α-olefin and triethylaluminum. The method for producing an α-olefin according to 1) or (2). (4) The zirconium-based complex catalyst is represented by the following general formula (I): ZrX ¹ _y A _4-y ... (I) (wherein X ¹ and A may be the same or different; bromine atom, iodine MotoHara Komata represents a fluorine atom, aluminum halide y is represented by the indicating.) an integer of 0 to 4, (b) the following general formula _{^{(II) AlR 1 3 ··· (}} II) ( wherein among, R ¹ is an alkyl aluminum and (c) the following general formula _{^{(III) Al 2 R 2 3}} X 2 3 ··· (III) ( wherein represented by indicating.) an alkyl group having 2 to 8 carbon atoms , R ² represents an alkyl group having 2 to 8 carbon atoms, X ²
Represents a chlorine atom, a bromine atom, an iodine atom or a fluorine atom. The method for producing an α-olefin according to the above (2), which comprises an alkylaluminum halide represented by the formula (2). (5) The above (1) to (5), wherein the concentration of 1-butene in the α-olefin produced in the first step is 15 to 45% by weight.
The method for producing an α-olefin according to any one of (4). (6) The α-olefin according to any of (3) to (5) above, wherein the triethylaluminum generated in the third step of the ethylene substitution reaction step is recycled to the second step of the butene substitution reaction step. Production method. (7) The method according to any one of the above (3) to (6), wherein 1-butene in the α-olefin generated in the ethylene substitution step of the third step is recycled to the butene substitution reaction step of the second step. A method for producing an α-olefin.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The present invention, as described above, in the first step, ethylene is oligomerized to obtain an α-olefin having a Schulz-Flory distribution to separate 1-butene, and in the second step, the 1-butene is converted to triethylaluminum. A substitution reaction is performed to obtain tributylaluminum, and in the third step, the tributylaluminum is reacted with ethylene to obtain an α-olefin having a Poisson distribution. FIG. 1 is a flowchart showing a preferred embodiment of the present invention, and description will be made based on the flowchart.

The process for producing an α-olefin of the present invention will be described in the order of three steps. (1) First Step In the first step, ethylene is oligomerized to obtain an α-olefin having a Schulz-Flory distribution and 1-butene is separated. Methods for producing an α-olefin having a Schulz-Flory distribution include a method using a zirconium-based complex catalyst and a one-step synthesis method using alkylaluminum, but a method using a zirconium-based complex catalyst is preferable in terms of effect. Various kinds of zirconium-based complex catalysts can be used, but those comprising the following components (a), (b) and (c) are preferred.

The component (a) is represented by the general formula (I).
Aluminum halide, specifically, ZrC
l_Four, ZrBr_Four, ZrI_Four, ZrF_Four, ZrBrCl
_Three, ZrBr_TwoCl_Two, ZrBr_ThreeTo mention Cl etc.
Can be. Among them, ZrCl _FourIs preferred. Note that this
Can be used alone or in combination of two or more.
May be used.

The component (b) is represented by the general formula (II).
Alkyl aluminum, specifically, Al (C
H_Three)_Three, Al (C_TwoH_Five)_Three, Al (n-C_ThreeH₇)
_Three, Al (iso-C_ThreeH₇)_Three, Al (n-C
_FourH₉)_Three, Al (iso-C_FourH ₉)_Three, Al (C_Five
H₁₁)_Three, Al (C₆H₁₃)_Three, Al (C₈H₁₇)_Threeetc
Can be mentioned. Among them, Al (C_TwoH_Five)
_Three(Hereinafter also referred to as TEA) is preferred. Note that this
Can be used alone or in combination of two or more.
May be used.

The component (c) is an alkylaluminum halide represented by the general formula (III), and specifically, Al ₂ (CH ₃ ) ₃ Cl ₃ and Al ₂ (CH ₃ ) ₃ B
r ₃ , Al ₂ (C ₂ H ₅ ) ₃ Cl ₃ , Al ₂ (C
_{2 H 5) 3 Br 3,} Al 2 (C 2 H 5) 3 I 3, Al 2
_{(N-C 3 H 7)} 3 Cl 3, Al 2 (iso-C
_{3 H 7) 3 Cl 3,} Al 2 (n-C 4 H 9) 3 Cl 3,
_{Al 2 (iso-C 4 H} 9) can be exemplified ₃ Cl _3, and the like. Among them, Al ₂ (C ₂ H ₅ ) ₃ Cl ₃ (hereinafter, referred to as Al ₂ (C ₂ H ₅ ) ₃ Cl ₃
Also called ethylaluminum sesquichloride (EASC). Is preferred. These may be used alone or in combination of two or more.

[0012] The catalyst is used in the above-mentioned (a) and (b) in an inert solvent.
And (c) by contacting the components. Examples of the inert solvent include aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, chlorobenzene, dichlorobenzene, and chlorotoluene or halogen-substituted products thereof; aliphatic hydrocarbons such as pentane, hexane, heptane, octane, nonane, and decane; Examples thereof include alicyclic hydrocarbons such as cyclohexane and decalin, and halogenated hydrocarbons such as dichloroethane and dichlorobutane. Among them, benzene, toluene, xylene, chlorobenzene, and cyclohexane are preferable, and benzene and cyclohexane are particularly preferable.

The contact ratio of the components (a), (b) and (c) at the time of preparing the catalyst is 10 to 200 mmol, preferably 20 to 100 mmol, and 5 to 5 mmol of the component (a) per liter of the solvent. ~ 750 mmol, preferably 10 ~
The range is 330 mmol, the component (c) is 20 to 1,200 mmol, preferably 40 to 830 mmol. Further, from the viewpoint of catalytic activity, Al / Zr (molar ratio) is set to 2-1.
5, It is preferable to set the component (c) / component (b) (molar ratio) in the range of 1 to 10.

The order of contact between the components (a), (b) and (c) is not particularly limited. The contact of each catalyst component is carried out at 40 to 100 ° C. for 10 minutes to 3 hours under an atmosphere of an inert gas such as argon.
The stirring may be performed for a time. Further, a fourth component may be added as necessary during the preparation of the catalyst and / or the oligomerization reaction. As the fourth component, a sulfur compound, a phosphorus compound, a nitrogen compound, or the like can be used from the viewpoint of improving the purity of the linear α-olefin.

Here, the sulfur compound includes dimethyl sulfide, diethyl sulfide, dipropyl sulfide, dihexyl sulfide,
Thioether compounds such as dicyclohexyl sulfide, dialkyl disulfide compounds such as dimethyl disulfide, diethyl disulfide, dipropyl disulfide, dibutyl disulfide, dihexyl disulfide, and ethyl methyl disulfide; thiophene, 2-methylthiophene, 3-methylthiophene; Thiophene compounds such as 2,3-dimethylthiophene, 2-ethylthiophene and benzothiophene; heterocyclic sulfur compounds such as tetrahydrothiophene and thiopyran; aromatic sulfur compounds such as diphenyl sulfur, diphenyl disulfide and methylphenyl disulfide; thiourea And the like.

Examples of the phosphorus compound include phosphine compounds such as triphenylphosphine, triethylphosphine, tripropyl, tributylphosphine and trioctylphosphine. Examples of nitrogen compounds include methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, cyclohexylamine, aniline, benzylamine, naphthylamine, dimethylamine, diethylamine, dibutylamine, diphenylamine, methylphenylamine, trimethylamine, triethylamine, triethylamine. Organic amine compounds such as butylamine, triphenylamine, pyridine and picoline can be exemplified.

Among these fourth components, dimethyl disulfide, thiophene, thiourea, triphenylphosphine,
Preferred examples include tributylphosphine, trioctylphosphine, and aniline. These may be used alone or in combination of two or more. The amount of the fourth component used is in the range of 0.1 to 6 mol based on 1 mol of the zirconium component (a).

In the first step, an oligomerization reaction of ethylene is carried out using the catalyst prepared as described above to produce an α-olefin having a Schulz-Flory distribution (including 1-butene). The amount of the catalyst used is usually diluted with the inert solvent, and the zirconium compound is used at a concentration of 0.1 to 2 mmol per liter of the inert solvent. If necessary, 0.1 to 10 mmol of the fourth component is added per liter of the inert solvent. When the fourth component is used at the time of preparing the catalyst, the concentration may be adjusted to the above concentration.

The reaction temperature is usually in the range of 80 to 150 ° C, preferably 100 to 130 ° C. The reaction pressure is usually 0.5 MPa or more, preferably 2.5 MPa or more. The reaction time is generally in the range of 5 minutes to 2 hours, preferably 15 minutes to 1 hour 30 minutes. Note that all operations from the preparation of the catalyst to the end of the oligomerization reaction are desirably performed in an atmosphere of an inert gas such as argon while avoiding air and moisture.

After completion of the reaction, the reaction product is adiabatically flushed to remove unreacted ethylene (not shown), the catalyst is deactivated with water, alcohol, sodium hydroxide or the like, and then decalcification is performed. 1-butene by distillation, a reaction solvent,
It is separated into α-olefins having 6 or more carbon atoms. 1-Butene is dried and dehydrated (not shown) and provided to the second step.
The reaction solvent is recycled, and the α-olefin having 6 or more carbon atoms is mixed with that from the third step and distilled to a required fraction. The concentration of 1-butene in the α-olefin should be adjusted to 15 to 45% by weight, preferably 20 to 40% by weight. If the concentration is too high, the purity of the α-olefin decreases, and if it is too low, the yield (yield) of the α-olefin having 6 to 10 carbon atoms decreases, which is not preferable.

(2) Second Step In the second step, 1-butene from the first step is reacted with triethylaluminum (hereinafter also referred to as TEA) to produce tributylaluminum (hereinafter also referred to as TBA). This reaction is referred to as a butene substitution reaction,
This reaction formula is represented by the following formula. TEA + 1-butene → TBA + ethylene In this case, 1-butene / TEA (molar ratio) is 3 to 30, and the temperature is 150 to 30.
The reaction is performed under the conditions of 0 ° C., preferably 200 to 250 ° C., a pressure of 3 MPa or less, preferably 1 MPa or less, and an average residence time of 60 seconds or less. 1-butene is separated from the reaction product by distillation, and TBA is subjected to a third step together with unreacted TEA. Further, TEA is further separated by distillation (TEA distillation) (not shown), and only TBA is separated. It may be subjected to three steps. 1-butene is recycled.

(3) Third Step In the third step, the TBA from the second step is reacted with ethylene (ethylene growth reaction) to obtain a higher trialkylaluminum, and then the higher trialkylaluminum is substituted with ethylene. (Ethylene substitution reaction) to obtain an α-olefin having a Poisson distribution and TEA.

In the ethylene growth reaction, a temperature of 50 to
200 ° C, preferably 100-150 ° C, pressure 10-2
It is performed under the conditions of 5 MPa, preferably 15 to 25 MPa, and an average residence time of 1 to 5 hours. The produced higher trialkylaluminum (including TBA) is reacted with ethylene to obtain α
Obtaining olefins (including 1-butene) and TEA; This ethylene substitution reaction is represented by the following equation. AlR ₃ + ethylene → α-olefin (including 1-butene) + TEA (where R represents a higher alkyl group)

In this case, the ethylene / higher trialkylaluminum (molar ratio) is 3 to 30, and the temperature is 100 to 3
The reaction is carried out under the conditions of 00 ° C, preferably 200 to 250 ° C, a pressure of 3 MPa or less, preferably 1 MPa or less, and an average residence time of 60 seconds or less. From the reaction product, 1-butene and a relatively light α-olefin (having 6 to 10 carbon atoms) are separated by distillation, and the 1-butene is recycled to the second step to obtain light α.
The olefin is mixed with the α-olefin from the first step. From the bottom of the distillation column, TEA and heavy α-olefin (having 12 or more carbon atoms) are further separated by distillation. T
The EA is recycled to the second step and the heavy α-olefin is mixed with the α-olefin from the step. The α-olefin mixture from the first, second, and third steps is an α-olefin that has a high yield of α-olefins having 6 to 10 carbon atoms and has a high purity and contains linear α-olefins.

[0025]

[Example 1]

(First step) 50 mmol of anhydrous zirconium tetrachloride (ZrCl ₄ ) and dried benzene 50 were placed in a 1,000-liter flask equipped with a stirrer under an argon atmosphere.
0 ml was introduced and stirred for 10 minutes. After adding 58.4 mmol of triethylaluminum (TEA) and stirring for about 10 minutes, 291.6 mmol of ethylaluminum sesquichloride (EASC) [(EAS
C + TEA) / ZrCl ₄ (molar ratio) = 7, EASC /
TEA (molar ratio) = 5] and stirred at 70 ° C. for 1 hour to form a zirconium complex as a catalyst. Next, 250 ml of dry benzene was added to a 1 liter autoclave equipped with a stirrer under a dry argon atmosphere, and the zirconium complex solution prepared above was injected into a Z syringe with a syringe.
0.2 mmol of rCl ₄ was added, followed by 1 mmol of thiophene. When all the addition was completed, the temperature of the autoclave was raised to 115 ° C., and dried ethylene was poured at once through a regulator until the reaction pressure reached 6.4 MPa. Thereafter, the reaction was performed for 1 hour. During this time, ethylene was continuously charged to keep the reaction pressure constant. After the completion of the reaction for one hour, the autoclave was cooled to room temperature, and the catalyst was deactivated by pressing an aqueous sodium hydroxide solution into the autoclave. After the catalyst was deactivated, the autoclave was heated again to 40 ° C., and 1-butene was completely expelled while bubbling with nitrogen. The expelled 1-butene was dried, dehydrated and collected while passing through a molecular sieve 3A. The remaining reaction product liquid was filtered for wax using a filter paper. The wax on the filter was thoroughly washed with benzene and then dried over anhydrous potassium carbonate.

(Second step) Triethyl aluminum (T
EA) and 1-butene produced by the reaction of the first step are 1
-Butene / TEA (molar ratio) 10 was introduced into a butene displacement reactor, and under the reaction conditions of 300 ° C., 1 MPa and an average residence time of 0.5 second, ethylene in TEA was replaced with 1-butene, and tributyl aluminum (TBA ) Got. TEA
Was 95%, and TBA and ethylene as catalysts were obtained.

(Third Step) The tributylaluminum (TBA) prepared in the second step and ethylene are supplied to the tubular reactor in a molar ratio of the former: the latter = 1: 50, and 1
The ethylene growth reaction was performed under the conditions of 00 ° C., 20 MPa, and an average residence time of 3 hours. The carbon number distribution of the obtained higher trialkylaluminum followed a Poisson distribution, and the average carbon number was 6 to 10. Next, after removing 1-butene from the obtained reaction product, ethylene was supplied at a molar ratio of 10 times to the remaining higher alkyl aluminum, and
The ethylene substitution reaction was performed under the conditions of 70 ° C., 1 MPa, and an average residence time of 0.5 seconds. At this time, the conversion of higher trialkylaluminum was 95%, and α-olefin and T
EA was obtained. The α-olefin having 6 or more carbon atoms obtained in the first step and the third step was mixed, and 15 g of undecane was added as an internal standard for gas chromatography, followed by gas chromatography analysis. The results (C _{6 to} C ₁₀ yield, C ₁₀ purity, C ₁₈ purity) are shown in Table 1.

Example 2 The procedure of Example 1 was repeated except that the solvent used in the preparation of the catalyst in the first step was changed to cyclohexane, and the amount of the catalyst was changed to 50 mmol of anhydrous ZrCl ₄ , 100 mmol of TEA, and 350 mmol of EASC. Carried out. Table 1 shows the results. Comparative Example 1 In Example 2, only the reaction in the first step was performed. In this reaction, the product distribution is a Schulz-Flory distribution. Therefore, from the gas chromatographic analysis of the α-olefins having 8 to 18 carbon atoms, the yield of carbon atoms of the α-olefins having 4 carbon atoms and the carbon Number 6-1
The yield of α-olefin of 0 was determined. Table 1 shows the results.

Comparative Example 2 In Example 1, only the reaction in the third step was carried out using tributylaluminum (TBA) as a reagent. Table 1 shows the results. Comparative Example 3 In Example 1, only the reaction in the third step was performed using the reagent triethylaluminum (TEA). Table 1 shows the results.

[0030]

[Table 1]

[0031]

[Table 2]

[0032]

According to the present invention, α-α having 6 to 10 carbon atoms is used.
An α-olefin containing a linear α-olefin with a high olefin yield and high purity can be obtained.

[Brief description of the drawings]

FIG. 1 is a flow chart showing a preferred embodiment of the method of the present invention.

Continued on front page F-term (reference) 4J028 AA01A AB00A AC24A BC15B BC19B EB02 FA02 FA07 4J100 AA02P CA01 FA10 FA41

Claims (7)

[Claims] 1. In a first step, ethylene is oligomerized to obtain an α-olefin having a Schulz-Flory distribution to separate 1-butene. In a second step, the 1-butene is substituted with triethylaluminum to cause a substitution reaction. A process for producing α-olefin having a Poisson distribution by reacting the tributyl aluminum with ethylene in a third step. 2. The method for producing an α-olefin according to claim 1, wherein in the first step, ethylene is oligomerized using a zirconium-based complex catalyst. 3. In the third step, tributylaluminum is reacted with ethylene to obtain a higher trialkylaluminum, and then the higher trialkylaluminum is subjected to a substitution reaction with ethylene to obtain an α-olefin and triethylaluminum. The method for producing an α-olefin according to claim 1. 4. A zirconium-based complex catalyst comprising: (a) ZrX ¹ _y A _4-y ... (I) wherein X ¹ and A may be the same or different; atom, a bromine atom, an iodine MotoHara Komata represents a fluorine atom, aluminum halide y is represented by the indicating.) an integer of 0 to 4, (b) the following general formula _{^{(II) AlR 1 3 ··· (}} II) (in the formula, R ¹ represents an alkyl group having 2 to 8 carbon atoms.) alkyl aluminum and (c) the following general formula represented by _{^{(III) Al 2 R 2 3}} X 2 3 ··· (III) ( wherein, R ² represents an alkyl group having 2 to 8 carbon atoms, X ²
Represents a chlorine atom, a bromine atom, an iodine atom or a fluorine atom. 3. The method for producing an α-olefin according to claim 2, comprising an alkylaluminum halide represented by the formula: 5. The method according to claim 1, wherein the concentration of 1-butene in the α-olefin produced in the first step is 15 to 45% by weight.
5. The method for producing an α-olefin according to any one of items 1 to 4. 6. The production of α-olefin according to claim 3, wherein the triethylaluminum produced in the third step of the ethylene substitution reaction is recycled to the second step of the butene substitution reaction. Method. 7. The method according to claim 3, wherein 1-butene in the α-olefin produced in the third step of substituting ethylene is recycled to the second step of substituting butene.
The method for producing an α-olefin according to any one of the above.