JPH03103406A - Preparation of linear alpha-olefin - Google Patents

Abstract

PURPOSE:To prepare the subject highly pure oligomer extremely reduced in the contamination of organic halides by subjecting a polymerization reaction product to a specific catalyst-deactivating treatment, the polymerization reaction product being prepared by polymerizing ethylene in the presence of a catalyst comprising a Zr compound and an organic Al compound. CONSTITUTION:Ethylene is first polymerized in the presence of a catalyst comprising a Zr compound and an organic Al compound. The prepared linear alpha- olefin-containing polymerization solution is mixed with a deactivating agent (preferably water or alcohol) against the Zr compound in an amount of 0.5-3.5 mole times that of the Zr compound. After the unreacted ethylene is removed, the reaction product solution is mixed with a basic deactivating agent (e.g. ammonia and/or an amine) to perfectly deactivate the catalyst. ZrCl4 and ethylsesquichloride are employed as the Zr compound and the organic Al compound, respectively, in the catalyst and further the catalysts are preferably combined with thiophene.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to a method for producing a linear α-olefin, and more specifically, relates to a method for producing a linear α-olefin, which is an ethylene oligomer.
Concerning a method for producing olefins with high purity. [Prior art and problems to be solved by the invention] Linear α-
Polyolefins are useful as modifying comonomers in the field of polyolefin production, or as plasticizers and surfactants when alcoholized. Such linear α-olefins can be prepared using a two-component catalyst consisting of titanium tetrachloride and ethylaluminum dichloride,
A 31rF. It can be produced by oligomerizing ethylene in the presence of a separate catalyst. In addition, in recent years, a two-component catalyst using a zirconium ((Zr) compound instead of the titanium compound described above has been proposed as a catalyst with even higher activity. For example, JP-A-58-109428 Publication No. 5G-30042, Japanese Patent Publication No. 58-2
No. 01729 and Japanese Unexamined Patent Publication No. 113138/1988 disclose 2r&separation catalysts using a zirconium compound and an aluminum compound, respectively. Moreover, in US Pat. No. 4,488,815, in order to increase the activity of a 2t-type catalyst consisting of a zirconium compound and an aluminum compound, a tertiary amine, which is a Lewis base, and a secondary amines, ethers, phosphine oxides, alkyl or aryl phosphates,
Catalysts containing sulfoxide and the like have been disclosed. And from the past. In the production method of &l-shaped α-olefins, improving product purity is a problem. It is generally known that in order to improve the purity of linear α-olefins, the polymerization conditions are low temperature and high ethylene pressure. Specifically, a low temperature condition of 100 to 130°C and a high pressure condition of 30 to 80 kg/cm2G are set. However, effective recovery of unreacted ethylene after the polymerization reaction is also required for the industrial production method of linear α-olefins, and in response to this requirement, a A method is adopted in which the polymerization reactants are transferred to a flasher maintained at a constant pressure and unreacted ethylene is recovered. As a result, side reactions further proceed within the flasher, resulting in a problem of reduced product purity. In order to solve this problem, it would be better to shorten the residence time of the polymerization reaction product solution in the flasher, but it is possible to recover unreacted ethylene with a short residence time without reducing purity. Designing a flasher is difficult. An object of the present invention is to solve the above-mentioned conventional problems and to provide a method for producing highly pure linear α-olefins in a method for producing linear α-olefins by oligomerizing ethylethiol. ．． [Means for Solving the Problems] The present invention for solving the problems described above uses a linear α-olefin obtained by polymerizing ethylene in the presence of a catalyst obtained from a zirconium compound and an organoaluminum compound. First, a deactivating agent that deactivates the zirconium compound is added to the polymerization reaction raw solution containing the zirconium compound at a ratio of 0.5 to 3.5 times the amount of the zirconium compound, and then unreacted ethylene is removed. This is a method for producing a linear α-olefin, which is characterized by adding a basic deactivator. In the present invention, a procedure for deactivating a catalyst in a polymerization reaction solution containing linear α-olefins obtained by polymerizing ethylene in the presence of a catalyst obtained from a zirconium compound and an organoaluminum compound is performed. is important. below. The procedure for deactivating the catalyst in the fff reaction product solution and its polymerization reaction solution will be explained in order. Monopolymerization reaction product liquid - The polymerization reaction product liquid suitable for applying the method of the present invention is a polymerization reaction product obtained by polymerizing ethylene in the presence of a catalyst obtained from a zirconium compound and an organoaluminum compound. If it is a stock solution, it may be a polymerization reaction product stock solution obtained by polymerizing the zirconium compound and the organoaluminum compound in the presence of a two-part catalyst, but the effects of the present invention A polymerization reaction product solution that can exhibit good performance is a polymerization reaction product solution obtained by polymerization in the presence of a three-component catalyst obtained from the above-mentioned zirconium compound, an organoaluminium compound, and a Lewis base. ■ Zirconium compound The zirconium compound that can be used in the method of the present invention has the following formula Z rXa As-a [11 (wherein, X and A may be the same or different, and each , Cl, Br, or engineering.Also, a represents an integer from 0 to 4.). Specific examples of the zirconium halide represented by the formula [11] include ZrCla. ZrBra, ZrIa, Z
rBrClx. Examples include ZrBr2 Cfl. Among these, Zrcla is particularly preferred.
Note that these may be used alone or in combination of two or more. The organoaluminum compound used in the method of this invention has the following formula AJI Rl. 5 Q+. 5 [2] (
In the formula, R represents an alkyl group having 1 to 20 carbon atoms, and Q represents Cl, Br, or I. Note that the above formula is AM
It can also be expressed by 2R3 Q3. ) and/or the following formula: A Rb Q'3-b [3] (in the formula,
R' and Q' represent the same meanings as R and Q above, respectively. Moreover, b represents an integer from 1 to 3. However, R' and Q' may be the same or different. ) can be mentioned. The alkylaluminum sesquihalide represented by the formula [21] is not particularly limited as long as R and Q each satisfy the above conditions in the formula [21], and specific examples include, for example, methyl Aluminum sesquichloride, methylaluminum sesquibromide, ethylaluminum sesquichloride, ethylaluminum sesquipromide, ethylaluminum sesquiiodide, ethylaluminum bromchloride,
Examples include probyl aluminum sesquichloride, improvil aluminum sesquichloride, butyl aluminum sesquichloride, isobutyl aluminum sesquichloride, pentyl aluminum sesquichloride, octyl aluminum sesquichloride, and the like. Among these, R is preferably a methyl group, an ethyl group, a proyl group, a butyl group, etc., and an ethyl group is particularly preferred. As for Q. Cl is preferred. Specifically, ethylaluminum sesquichloride can be cited as a suitable example. Note that these alkyl aluminum halides may be used alone or in combination of two or more. The alkylaluminum compound represented by the formula [31] is not particularly limited as long as R' and Q' in the formula [31] satisfy the above conditions, and specific examples include, for example, triethyl Aluminum, triethylaluminum, triprobylaluminum, triimbrobylaluminum, tributylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, diethylaluminum bromide, diethylaluminum chloride, diethylaluminum iodide, ethylaluminum dibromide, Examples include ethylaluminum dichloride and ethylaluminum diiodide. However, among the compounds represented by the formula [31],
Preferably, b is 3 or 2. No. 31,
R' is preferably an ethyl group, a probyl group, a butyl group, an isobutyl group, etc., and an ethyl group is particularly preferred. As Q', sentence C is preferable. Specifically, for example, triethylaluminum, diethylaluminum chloride, and ethylaluminum dichloride are suitable. Incidentally, these alkylaluminum compounds can be used alone or in combination of two or more kinds as an organoaluminum compound. Examples of the Lewis base that can be used in the method of the present invention include thioethers, alkyl disulfides, thiophenes, thioureas, sulfides, and phosphines. Examples of the thioethers include dimethyl sulfide, diethyl chloride, dipropyl sulfide,
Examples include dihexyl sulfide, dicyclohexyl sulfide, diphenylthioether, etc. Examples of the alkyl disulfides include dimethyl disulfide [(CH3)2S2]. Jetyl disulfide, diprovir disulfide, dibutyl disulfide, dihexyl disulfide,
Examples include dicyclohexyl disulfide and ethylmethyl disulfide. The thiophenes include thiophene, 2-methylthiophene, 3-methylthiophene, 2,3-dimethylthiophene, 2-ethylthiophene, penzothiophene,
Examples include tetrahydrothiophene and penzothiophene. Examples of the sulfides include methyl sulfide, ethyl sulfide, and butylsulnoid. Examples of the phosphines include triphenylphosphine, triethylphosphine, tributylphosphine, tripropylphosphine, trioctylphosphine, tricyclohexylphosphine, and the like. Examples of the primary amines include methylamine, ethylamine, probylamine, butylamine, benzylamine, hexylamine, cyclohexylamine,
Examples include organic amines such as octylamine, decylamine, aniline, penzylamine, naphthylamine, trimethylamine, triethylamine, tributylamine, triphenylamine, pyridine, and vicoline. These compounds may be used alone or in combination of two or more. Among the various Lewis bases mentioned above, dimethyl disulfide, thiophene, thiourea, triphenylphosphine, trioctylphosphine, aniline, etc. are preferred, and thiophene is particularly preferred. In the method of this invention, as mentioned above, the catalyst for providing the polymerization reaction solution that can exhibit the effects of the invention well is 3, which is obtained from a zirconium compound, a suppressor aluminum compound, and a Lewis base.
A fractional catalyst is preferred. However, a mixture of the alkyl aluminum sesquihalide and the alkyl aluminum compound is particularly selected as the organoaluminum compound, and a catalyst that combines this mixture, a zirconium compound, and the Lewis base, and a catalyst that combines the zirconium compound and the alkyl aluminum sesquihalide. Catalysts in combination with the above Lewis bases are preferred (particularly catalysts consisting of a mixture of alkyl aluminum sesquihalides and trialkylaluminum, zirconium tetrachloride, and thiophene, as well as alkyl aluminum sesquihalides, zirconium tetrachloride, and thiophene). A catalyst consisting of is preferred. This is because the use of such a catalyst makes it possible to further reduce the wax content in the product produced by the oligomerization reaction and to reduce the f of zirconium halide.
This is because the yield of linear α-olefin per fi1 can be increased, and the purity of the obtained linear α-olefin can be increased. When a mixture of the alkyl aluminum sesquihalide and the alkyl aluminum compound is used as a catalyst, the blending ratio of the alkyl aluminum sesquihalide and the alkyl aluminum compound is usually such that the alkyl aluminum compound is 50 mol% on a CAM basis. ) or less, preferably 30 mol% CAN standard) or less. In the method of the present invention, there is no particular restriction on the method for preparing the catalyst from the zirconium compound, the organoaluminum compound, and the Lewis base, but the zirconium compound and the organoaluminum compound are mixed in a suitable solvent. It is preferable to make the catalyst preparation liquid viable by contacting it in the presence of the catalyst, and prepare the catalyst liquid by mixing this catalyst preparation liquid and the Lewis base during or prior to the polymerization (oligomerization) of ethylene. ．． When preparing this catalyst preparation liquid or catalyst liquid, the temperature is 10 to 120°C at an appropriate temperature (usually, for example, lower than the temperature of the polymerization reaction, specifically in the range of BO to 80°C).
It is preferable to activate the catalyst by heating it for a minute. As the solvent, an inert solvent can usually be used, such as benzene,
Aromatic hydrocarbons or their halogen-substituted products such as toluene, xylene, chlorobenzene, ethylbenzene, dichlorobenzene, and chlorotoluene; Aliphatic paraffins such as pentane, hexane, heptane, octane, nonane, and decane; Naphthenes such as cyclohexane and decalin Paraffins: Examples include haloalkanes such as dichloroethane and dichlorobutane. Among these, cyclohexane, benzene, toluene, xylene, and chlorobenzene are preferred (especially cyclohexane and benzene are preferred). These solvents can be used alone or in combination of two or more. In this invention, the blending ratio of the zirconium compound, organoaluminum compound, Lewis base, and solvent is usually 0.0% of the zirconium compound per 250mM of the solvent. Ol~5 mmol, preferably 0.03~1
mmol, organoaluminum compound usually 0.05 to 1
5 mmol, preferably 0.06 to 3 mmol, usually 0.01 to 20 mmol of a Lewis base, preferably a sulfur compound (thioethers, alkyl disulfides, thiophenes, thioureas, sulfides) as a Lewis base. When using phosphines or primary amines as the Lewis base, the amount is 0.02 to 20 mmol, and when using phosphines or primary amines as the Lewis base, the amount is 0.01 to 5 mmol. Regarding the blending ratio of the zirconium compound and the organic aluminum compound, A9. Even more preferable results can be obtained by setting the molar ratio of /Zr in the range of 1 to 15. Further, when using an alkylaluminum sesquihalide and a trialkylaluminium together as an organoaluminum compound, it is preferable that the trialkylaluminum is 50 mol% or less, preferably 30 mol% or less, based on the whole organoaluminum compound. During polymerization, the catalyst liquid can be further mixed with the solvent as necessary to adjust the concentration before use. Polymerization (oligomerization) of ethylene is carried out by bringing the catalyst or catalyst solution thus prepared into contact with ethylene or a gas containing ethylene in the presence of the solvent at a predetermined reaction temperature and reaction pressure. It is done efficiently. The gas containing ethylene used is:
Ethylene gas for polymerization such as an inert gas containing ethylene, purified ethylene gas for polymerization, and high purity ethylene can be used, with high purity ethylene being preferred. The reaction temperature during polymerization is usually 50 to 200°C, preferably 100 to 150°C. The reaction pressure is
Usually 5 kg/cm2G or more, preferably 25 kg
/cm2G or more, more preferably 30 to 80 kg/
cm211; The reaction time is usually about 5 minutes to 2 hours, preferably about 15 minutes to 1 hour. It is desirable to perform all operations from the preparation of the catalyst to the completion of the polymerization reaction while avoiding air and moisture. Preferably, the catalyst is prepared under an atmosphere of an inert gas such as nitrogen or argon. It is also desirable to thoroughly dry catalyst preparation raw materials, solvents, reaction raw materials, etc. However, the coexistence of trace amounts of moisture and air may increase catalyst activity and product selectivity. Below, an example of the method for obtaining a polymerization reaction solution containing a linear α-olefin in the present invention will be described in more detail. That is, in a container equipped with a stirrer, the zirconium compound such as zirconium tetrachloride and the organic aluminum compound such as ethylaluminum sesquichloride are dissolved in the solvent such as cyclohexane under an atmosphere of an inert gas such as argon or nitrogen. After that, while stirring, 60~8
Prepare a catalyst preparation solution by heating at 0°C for 120 minutes. A portion of this catalyst preparation solution was introduced into another container equipped with a stirrer under the above inert gas atmosphere, diluted with the above solvent such as cyclohexane, the above Lewis base such as thiophene was added at around room temperature, and the catalyst was stirred. Prepare the liquid. By preparing the catalyst in this way, a complex catalyst of a zirconium halide such as zirconium tetrachloride and an alkylaluminum compound is formed, and the yield of the desired product and the purity of the mono-alpha-olefin are improved. can be improved. Next, under an inert gas atmosphere, the catalyst was introduced by pressure transport into a reactor maintained at 50 to 60°C, and while stirring the catalyst liquid, a gas containing ethylene such as high-purity ethylene was introduced. Oligomerize under the above reaction conditions. In the manner described above, a polymerization reaction product solution containing linear α-olefins is obtained. - Catalyst deactivation - In this invention, the method of adding a catalyst deactivator is important when the catalyst deactivator is added to the polymerization reaction product liquid obtained by ethylene polymerization (oligomerization) to stop the reaction. ．． That is, the catalyst is deactivated before and after supplying the polymerization reaction product solution obtained as described above to, for example, a flasher and recovering unreacted ethylene. The catalyst is deactivated before recovery of unreacted ethylene by adding a compound capable of reacting with a zirconium compound to the polymerization reaction product solution. Compounds that can react with the zirconium compound include:
For example, water, alcohol, amines, etc. can be used, with water and/or alcohol being particularly preferred. Examples of alcohols include monohydric alcohols, polyhydric alcohols, cyclic alcohols, acyclic alcohols, aliphatic alcohols, and aromatic alcohols. These alcohols may be used alone or in combination of two or more. It is also possible to use a combination of water and alcohol. The amount of the compound capable of reacting with the zirconium compound added is 0.5 to 3.5 moles relative to the zirconium compound. Less than 0.5 mol of the above compound as a deactivating agent per 1 mol of the zirconium compound is not sufficient to deactivate the zirconium compound, and if the amount of the deactivating agent exceeds 3.5 mol, the halogenation generated during activation is Hydrogen is added to the α-olefin and organic halogenated compounds are mixed into the α-olefin product, which is undesirable because it reduces the purity and quality of the product. Regarding this initial catalyst deactivation operation, there are no particular restrictions regarding the temperature and pressure conditions, but the temperature is preferably 50 to 130°C, particularly 80 to 110°C. Under these conditions, the compound as a deactivator is added to the polymerization reaction product solution and mixed thoroughly. Although the time for this mixing cannot be absolutely defined depending on the volume of the polymerization reaction solution, it is usually 1 to 10 minutes. Unreacted ethylene can be recovered from the polymerization reaction product solution by lowering the atmospheric pressure of the polymerization reaction product solution lower than the pressure during the polymerization reaction. If the first catalyst deactivation operation is performed under a pressure lower than the pressure during the polymerization reaction, the first catalyst deactivation operation and the unreacted ethylene recovery operation can be performed at the same time, simplifying the equipment. It is possible to achieve something. However, it is preferable to supply a deactivator to the polymerization reaction product liquid immediately before supplying the polymerization reaction product liquid to the flasher, in order to avoid the influence of the deactivation reaction product of the zirconium compound. After collecting unreacted ethylene using a flasher, add a basic deactivator to completely deactivate the catalyst. By adding a basic compound, it is possible to prevent the addition of halogen derived from the catalyst to the linear α-olefin to be used, thereby further improving the purity of the linear α-olefin. Examples of the basic deactivator include ammonia and/or amines. Amines include methylamine, ethylamine, probylamine, butylamine, benzylamine, hexylamine, cyclohexylamine, octylamine, decylamine, aniline, penzylamine, naphthylamine, dimethylamine, jetylamine, dibutylamine, diphenylamine, methylphenylamine, trimethylamine. , triethylamine, tributylamine, triphenylamine, pyridine, picoline, etc. These amines can be used alone or in combination of two or more. The amount of the basic deactivator added is usually sufficient as long as it is in excess of the organoaluminum compound used in the polymerization reaction;
0 mole times, preferably 1 to 10 mole times. After the catalyst has been deactivated in this way, the polymerization reaction product has a carbon number of about 6 to 44, particularly a carbon number of about 6 to 20, and has no halogen added. α−
Contains a high fraction of olefins. On the other hand, wax by-products are significantly suppressed. After the catalyst has been deactivated, the polymerization reaction product liquid is subjected to ordinary post-treatment steps such as washing with water, extraction, separation by filtration, drying step, etc. to obtain a high-purity linear product, which is the target product. α-olefins can be recovered with high efficiency. That is, by the method of this invention, the number of carbon atoms is reduced from 6 to 2.
It is possible to stably obtain linear α-olefins with high purity in the range of about 0 with high yield and high selectivity. Furthermore, by selecting the reaction conditions, catalyst composition, concentration, etc., it is also possible to adjust the carbon number distribution of the raw material to an even narrower range. In addition, recovered unreacted ethylene or
The low-boiling fraction containing this can be used as it is, or after purification, it can be recycled and used as part of the reaction raw material. The linear α-olefin produced by the method of this invention can be used as a comonomer for producing various copolymers, and
It can be suitably used in various industrial fields such as raw materials for plasticizers and surfactants. [Example] Preparation of catalyst solution In a 1,000 mJl flask equipped with a stirrer, 1 part of anhydrous zirconium tetrachloride (ZrCjL4) was added under an argon atmosphere.
00 mmol and 500 mfL of dry cyclohexane
and stirred for 10 minutes. This includes triethyl aluminum (sometimes abbreviated as TEA) 15
After adding 13.3 mmol and stirring for about 10 minutes, ethylaluminum sesquichloride (EASC) was added.
541.7 mmol (sometimes abbreviated as ) was added, and the complex was formed with stirring at 70°C for an additional 2 hours. Next, 250 ml of cyclohexane and the above complex solution were added to a 500 ml three-necked flask under an argon atmosphere.
rCla was introduced to be 0.12 mmol, EASC was 0.85 mmol, and TEA was introduced to be 0.19 mmol,
A catalyst solution was prepared by adding 0.36 mmol of thiophene and stirring at room temperature for 10 minutes. (Examples 1 to 6 and Comparative Examples 1 to 6) α-olefin production example (Ethylene oligomer raw material) The catalyst solution prepared in the above catalyst preparation example was placed in a stirred autoclave of Σ IJI under a dry argon atmosphere. The gas was introduced by pressure-feeding argon. At this time, the temperature of the autoclave was maintained at 50 to 60°C. After filling the catalyst liquid, stirring was started and high-purity ethylene gas was introduced into the autoclave. The pressure is fl5kg/cm
Blow rapidly until it reaches 2G, then 120
The temperature was raised to ℃. Ethylene was continued to be introduced in the amount necessary to maintain the above pressure. The reaction was continued under these reaction conditions for 30 minutes. After reacting for 30 minutes, the pressure was depressurized and the temperature was lowered under the flash conditions shown in Table 1, and the type and amount of deactivating agent shown in Table 1 was injected. The liquid was collected, poured into a 30% ammonia aqueous solution, and stirred to perform final catalyst deactivation, and analyzed using a gas chromatograph. Table 1 shows the difference in purity of linear α-olefins with carbon number 14 (CN) - carbon number 16 (CI6) and carbon number 18 (C+s) at the start of flashing, after 5 minutes, and after 10 minutes. Ta. [Effect of the invention]

Claims (2)

[Claims] (1) A polymerization reaction product liquid containing a linear α-olefin obtained by polymerizing ethylene in the presence of a catalyst obtained from a zirconium compound and an organoaluminum compound,
First, a deactivator for deactivating the zirconium compound is added at a ratio of 0.5 to 3.5 times the mole of the zirconium compound, unreacted ethylene is removed, and then a basic deactivator is added. A method for producing a linear α-olefin, the method comprising: (2) The method for producing a linear α-olefin according to claim 1, wherein the catalyst is a catalyst obtained from a zirconium halide, an organoaluminum compound, and a Lewis base.