JPH107595A - Method for producing 1-hexene - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing 1-hexene by trimerizing ethylene, wherein a metal component of a chromium-based catalyst used in a trimerization reaction of ethylene is subjected to demineralization treatment after completion of the reaction. Very low concentration of used catalyst metal components from the reaction product liquid without taking out the generated polymer out of the system and without clogging the reactors, control valves, piping, pumps, etc. during deashing treatment 1- which can be removed up to
A method for producing hexene is provided. SOLUTION: After completion of the trimerization reaction, the chromium-based catalyst is deactivated, and then, while maintaining the reaction product solution at a temperature of 100 ° C. or more, water of 20% by volume or more based on the reaction product solution is supplied to the treatment system. The method further comprises a demineralization treatment step of removing the metal component contained in the chromium-based catalyst from the reaction product liquid by stirring the treatment system with a stirring station power of 1 KW / m ³ or more per unit volume. Hexene is manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing 1-hexene by trimerizing ethylene. More specifically, in the process of demineralizing the metal component of the chromium-based catalyst used in the ethylene trimerization reaction after the reaction is completed, the by-product polymer is not taken out of the system, and the reactor and control during demineralization are controlled. The present invention relates to a method for producing 1-hexene which can remove metal components of a used catalyst from a reaction product solution to an extremely low concentration without clogging devices such as valves, pipes, and pumps. 1 obtained by the present invention
-Hexene is linear low density polyethylene (LLDPE)
Is a very useful compound as a raw material comonomer or a plasticizer raw material.

[0002]

2. Description of the Related Art It is known to produce 1-hexene using a chromium-based catalyst in a reaction for trimerizing ethylene. For example, U.S. Pat. No. 3,347,840 and JP-A-62-265237 disclose chromium compounds,
A catalyst system comprising an aluminoxane and an ether compound such as dimethoxyethane is disclosed in JP-A-6-239920, and a catalyst system comprising a chromium compound, a pyrrole-containing compound and a metal alkyl is disclosed in JP-A-8-59732. Discloses a catalyst system comprising a chromium compound, an imide compound and a metal alkyl.

[0003] This production process generally comprises a trimerization reaction step, an unreacted ethylene recovery step, a catalyst deactivation step and a deashing step, and a fractionation step of 1-hexene and a solvent. By the way, in the trimerization of ethylene using the chromium catalyst system, any catalyst system inevitably produces a polymer by-product. Therefore, one of the most important technical issues in these processes is handling of the by-product polymer. That is, the by-produced polymer is supplied to the reactor in the step of recovering unreacted ethylene, the step of deactivating the catalyst and the step of deashing,
It is gradually formed in devices such as control valves, pipes, and pumps, and may cause clogging or hinder stable operation such as inhibiting heat transfer.

Further, if the metal component of the catalyst used remains in 1-hexene as the target product, the quality of the product is adversely affected, or the distillation column is clogged in the fractionation step of 1-hexene and the solvent. Therefore, it is necessary to remove the metal component of the used catalyst from the reaction product liquid.

[0005]

SUMMARY OF THE INVENTION Therefore, Japanese Patent Laid-Open No.
No. 49671 discloses a method for producing an α-olefin low polymer using a chromium-based catalyst, in which the shape of the by-product polymer in the reaction solution is specified by controlling the low polymerization reaction under specific reaction conditions. And a process of removing a by-product polymer out of the system using a solid-liquid separation device having a specific structure. However, in such a method, a new apparatus required for removing the by-product polymer must be installed, and the cost and service cost are unavoidably increased. In addition, since most of the metal components of the chromium-based catalyst used are contained in the solid polymer, the polymer containing chromium and aluminum is removed from the reaction solution, and the post-treatment of the polymer requires time and labor. there were. Further, there is a disadvantage that the reaction conditions are restricted because the shape of the by-produced polymer is specified, and the catalytic activity cannot be increased.

The present invention has been made in view of the above problems, and has as its object to provide a method for producing 1-hexene by trimerizing ethylene, wherein the metal component of the chromium-based catalyst used in the ethylene trimerization reaction is used. When the decalcification treatment was performed after the reaction was completed, the polymer was further used without removing the by-produced polymer to the outside of the system and without clogging devices such as reactors, control valves, piping, and pumps during the decalcification treatment. An object of the present invention is to provide a method for producing 1-hexene which can remove a metal component of a catalyst from a reaction product solution to an extremely low concentration.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that a method for producing 1-hexene by trimerizing ethylene in the presence of a chromium-based catalyst is disclosed. After completion of the trimerization reaction, the chromium-based catalyst is deactivated, then a specific amount of water is introduced into the reaction solution, and the mixture is heated and stirred at a specific temperature and condition, without taking out the by-product polymer out of the system. In addition, they found that the metal components of the used catalyst could be removed from the reaction product solution to an extremely low concentration without clogging the reactor, control valve, piping, pump, etc. during the deactivation treatment, and completed the present invention. I came to.

That is, the present invention relates to a method for producing 1-hexene by trimerizing ethylene in the presence of a chromium-based catalyst. While maintaining the temperature at １８０180 ° C., 20 to 200% by volume of water with respect to the reaction product liquid is introduced into the treatment system, and the treatment system is further stirred with a required power of 1 KW / m ³ or more per unit volume. And removing a metal component contained in the chromium-based catalyst from the reaction product liquid.

[0009]

Next, the present invention will be described in more detail.

In the present invention, 1-hexene is obtained by trimerizing ethylene in the presence of a chromium-based catalyst. The chromium-based catalyst comprises at least one of (A) a chromium compound, (B) an alkyl metal compound, and (C) an imide compound, a pyrrole-containing compound, and an ether compound used as desired. Consists of hetero-element containing organic compounds.

Although the chromium compound (A) used in the present invention is not particularly limited, for example, the following general formula (1): CrA _m B _n (1) (where m is 1 to 6) N is an integer of 0 to 4. A is an alkyl group having 1 to 20 carbon atoms, an aryl group, an arene, an alkoxy group, a carboxylate group, β
-Diketonate groups, β-ketoester groups and amide groups,
Represents one or more selected from the group consisting of a halogen atom, a hydroxyl group, a nitrate group, a sulfate group, a perchlorate group, a carbonyl and oxygen, and B represents a nitrogen-containing compound, a phosphorus-containing compound, an arsenic-containing compound, an antimony-containing compound , Or one or more selected from the group consisting of oxygen-containing compounds and sulfur-containing compounds).

In the above general formula (1), the number of carbon atoms is 1 to 2.
The alkyl group of 0 is not particularly limited, and examples thereof include a methyl group, an ethyl group, a butyl group, an allyl group, a neopentyl group, a cyclopentadienyl group, a pentamethylcyclopentadienyl group, and a trimethylsilylmethyl group. Is mentioned. The aryl group having 6 to 20 carbon atoms is not particularly limited, and examples thereof include a phenyl group and a toluyl group. The arene having 6 to 20 carbon atoms is not particularly limited, and examples thereof include benzene, ethylbenzene, and hexamethylbenzene. Although it does not specifically limit as a C1-C20 alkoxy group, For example, a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a hexyloxy group, a stearyloxy group, a phenoxy group, etc. are mentioned. Examples of the carboxylate group having 1 to 20 carbon atoms include, but are not particularly limited to, an acetate group, a propionate group, a butyrate group, a neopentanoate group, a 2-ethylhexanoate group, and an oxy-2 group. -Ethylhexanoate group, isooctanoate group, dichloroethylhexanoate group, laurate group, stearate group, oleate group, benzoate group or naphthenate group. Examples of the β-diketonate group having 1 to 20 carbon atoms include, but are not particularly limited to, acetylacetonate group, trifluoroacetylacetonate group, hexafluoroacetylacetonate group,
2,6,6-tetramethyl-3,5-heptanedionate group, 1,3-butanedionate group, 2-methyl-1,
Examples thereof include a 3-butanedionate group and a benzoylacetonate group. Although it does not specifically limit as a C1-C20 (beta) -ketoester group, For example, an acetylacetate group etc. are mentioned. The amide group is not particularly limited, but includes, for example, a dimethylamide group or a dicyclohexylamide group. Although it does not specifically limit as a halogen atom, For example,
Fluorine, chlorine, bromine or iodine. In the general formula (1), examples of the nitrogen-containing compound include, but are not particularly limited to, amines, pyridines, amides, and nitriles. Although it does not specifically limit as a phosphorus compound, For example, a phosphine, a phosphite, a phosphine oxide, etc. are mentioned. The antimony-containing compound is not particularly limited, but examples include triarylantimony and trialkylantimony. The oxygen-containing compound is not particularly limited, for example,
Examples thereof include water, carboxylic anhydride, ester, ether, alcohol, and ketone. Examples of the sulfur-containing compound include, but are not limited to, carbon disulfide, sulfone, thiophene, and sulfide.

The chromium compound represented by the above general formula (1) is not particularly limited. For example, chromium (II) dimethyl, chromium (III) trimethyl, chromium (IV) tetramethyl, chromium (III) Tris (η-allyl), dichromium (II) tetrakis (η-allyl), chromium (IV) tetrakis (neopentyl),
Chromium (IV) tetrakis (trimethylsilylmethyl), chromium (II) bis (cyclopentadienyl),
Chromium (II) bis (pentamethylcyclopentadienyl), chromium (III) tris (π-allyl), chromium (IV) tetrakis (π-allyl), chromium (II) diphenyl, chromium (0) bis (benzene) , Chrome (I
I) diphenyl (benzene), chromium (0) bis (ethylbenzene), chromium (0) bis (hexamethylbenzene), chromium (I) cyclopentadienyl (benzene), chromium (IV) tetramethoxide, chromium (I
V) tetraethoxide, chromium (IV) tetrapropoxide, chromium (IV) tetrabutoxide, chromium (I
V) Tetrahexyl oxide, chromium (IV) tetrastearyl oxide, chromium (IV) tetraphenoxide, chromium (II) bis (acetate), chromium (II
I) Tris (acetate), chromium (II) bis (propionate), chromium (III) tris (propionate), chromium (III) tris (butyrate), chromium (II) bis (2-ethylhexanoate), chromium ( III) Tris (2-ethylhexanoate), chromium (II) bis (isooctanoate), chromium (II
I) tris (isooctaneate), chromium (III) tris (oxy-2-ethylhexanoate), chromium (III) tris (dichloroethylhexanoate),
Chromium (III) tris (neopentanoate), chromium (II) bis (neopentanoate), chromium (II
I) tris (laurate), chromium (II) bis (laurate), chromium (III) tris (stearate),
Chromium (II) bis (stearate), chromium (II
I) Tris (oleate), chromium (II) bis (oleate), chromium (III) tris (benzoate),
Chromium (II) bis (naphthenate), chromium (II
I) Tris (naphthenate), chromium (II) oxalate, chromium (II) bis (acetylacetonate),
Chromium (III) tris (acetylacetonate), chromium (III) tris (trifluoroacetylacetonate), chromium (III) tris (hexafluoroacetylacetonate), chromium (III) tris (2,
2,6,6-tetramethyl-3,5-heptanedionate), chromium (III) tris (1,3-butanedionate), chromium (III) tris (2-methyl-1,3
-Butane dionate), chromium (III) tris (benzoylacetonate), chromium (III) tris (acetyl acetate), chromium (III) tris (dimethylamide), chromium (III) tris (dicyclohexylamide), fluorinated Chromium monochromate, chromium fluoride, chromium chloride, chromium chloride, chromium bromide, chromium bromide, chromium iodide, chromium iodide, chromyl chloride, chromium perchlorate , Hydroxychromium dichloride,
Examples thereof include chromium nitrate and chromium sulfate.

Further, trichlorotrianiline chromium (III), dichlorobis (pyridine) chromium (I
I), dichlorobis (4-ethylpyridine) chromium (I
I), trichlorotripyridinechromium (III), trichlorotris (4-isopropylpyridine) chromium (I
II), trichlorotris (4-ethylpyridine) chromium (III), trichlorotris (4-phenylpyridine) chromium (III), trichloro (1,4,7-trimethyl-1,4,7-triazacyclononane) Chromium (III), dichlorodinitrosylbis (4-ethylpyridine) chromium (II), dichlorodinitrosylbis (triphenylphosphine oxide) chromium (II),
Dichlorobis (triphenylphosphine oxide) chromium (II), trichlorotris (triphenylphosphine) chromium (III), trichlorobis (tributylphosphine) chromium (III) dimer, trichlorotris (butylacetate) chromium (III), trichlorotris ( Ethyl acetate) chromium (III), trichlorotris (tetrahydrofuran) chromium (III),
Trichlorotris (dioxane) chromium (III), trichlorotris (iso-propanol) chromium (II)
I), trichlorotris (2-ethylhexanol) chromium (III), triphenyltris (tetrahydrofuran) chromium (III), chromium (III) tris (acetate) acetic anhydride adduct, hydridotricarbonyl (η-cyclopentane) Dienyl) chromium (III) and the like.

Of these, chromium carboxylate compounds having a carboxylate group and chromium β having a β-diketonate group are preferred from the viewpoints of ease of handling and stability.
-Diketonate compounds are preferably used. More preferably, chromium (III) tris (2-ethylhexanoate), chromium (III) tris (naphthenate),
Chromium (III) tris (acetylacetonate), chromium (III) tris (trifluoroacetylacetonate), and chromium (III) tris (2,2,6,6-tetramethyl-3,5-heptanedionate) Used. Further, the above chromium compounds can be used alone or in combination of two or more.

The alkyl metal compound (B) used in the present invention is not particularly limited.
The following general formula (2) R _p MX _q (2) (where p is a number satisfying 0 <p ≦ 3, q is a number satisfying 0 ≦ q <3, and p + q is a number of 1-3. M represents lithium, magnesium, zinc, boron or aluminum, R represents one or more selected from an alkyl group having 1 to 10 carbon atoms, and X represents a hydrogen atom, an alkoxy group, an aryl group, and a halogen atom. Or aluminoxane, which is one or more selected from the group consisting of:

In the above general formula (2), the number of carbon atoms is 1 to 1.
The alkyl group of 0 is not particularly limited, and includes, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a cyclohexyl group, an octyl group, and the like. Although it does not specifically limit as an alkoxy group, For example, a methoxy group, an ethoxy group, a butoxy group, a phenoxy group, etc. are mentioned. As the aryl group,
Although not particularly limited, for example, a phenyl group and the like can be mentioned. Although it does not specifically limit as a halogen atom, For example, fluorine, chlorine, bromine, or iodine is mentioned.

In the above general formula (2), M is A
l, when p and q are each 1.5, AlR _1.5 X _1.5
Becomes Although such compounds do not exist in theory, they are usually conventionally expressed as sesqui-forms of Al ₂ R ₃ X ₃ , and these compounds are also included in the present invention.

Examples of the alkyl metal compound represented by the general formula (2) include methyllithium, ethyllithium, propyllithium, n-butyllithium, s-butyllithium, t-butyllithium, diethylmagnesium, and ethylbutylmagnesium. , Ethylchloromagnesium, ethylbromomagnesium, dimethylzinc, diethylzinc, dibutylzinc, trimethylborane, triethylborane, trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum, tricyclohexyl Aluminum, dimethylethylaluminum, diethylaluminum hydride, diisobutylaluminum hydride, diethylaluminum ethoxide, diethyl Rumi bromide phenoxide, dicyclohexyl phenyl aluminum, ethyl aluminum ethoxy chloride, diethylaluminum chloride, diethylaluminum bromide, diisobutylaluminum chloride, dicyclohexyl aluminum chloride,
Examples include methylaluminum sesquichloride, ethylaluminum sesquichloride, butylaluminum sesquichloride, ethylaluminum dichloride, isobutylaluminum dichloride and the like.

The aluminoxane used in the present invention is a hydrolysis product obtained by reacting the above-mentioned alkylaluminum compound with water in a quantitative ratio within a certain range. The method for hydrolyzing the alkylaluminum compound is not particularly limited, and can be synthesized by a known method. For example, (1) a method in which water is brought into contact with an alkyl aluminum compound as it is or a diluted solution of an organic solvent, (2) an alkyl aluminum compound and magnesium chloride hexahydrate, iron sulfate heptahydrate, copper sulfate pentahydrate. For example, a method of reacting with water of crystallization of a metal salt. Specifically, Japanese Patent Application Laid-Open Nos. Sho 62-265237 and
It is disclosed in Japanese Patent Application Laid-Open No. 2-148491. The molar ratio of the alkylaluminum compound to water during the hydrolysis is 1: 0.4 to 1: 1.2, preferably 1: 0.5 to 1:
1.0.

Of these alkyl metal compounds, triethylaluminum and triisobutylaluminum are preferably used in view of availability and activity. Not only can these alkyl metal compounds be used alone,
It is also possible to use a mixture of two or more.

The (C) hetero element-containing organic compound used as desired includes at least one compound selected from the group consisting of imide compounds, pyrrole-containing compounds and ether compounds. The imide compound may be any compound as long as it has an imide structure, and is not particularly limited. Examples thereof include maleimide, 1-chloroethene-1,2-dicarboximide, and 1-bromoethene-1,2-dicarboxyimide. Imide, 1-fluoroethene-1,2-dicarboximide, 1-trifluoromethylethene-1,2-dicarboximide, 1,2-dichloroethene-1,2-dicarboximide, citraconimide, 2- Butene-2,3
-Dicarboximide, 1-cyclopentene-1,2-
Dicarboximide, succinimide, α, α-dimethyl-β-methylsuccinimide, α-methyl-α-propylsuccinimide, glutarimide, 3,3-dimethylglutarimide, bemeglid, phthalimide, 3,
4,5,6-tetrachlorophthalimide, 1,2-cyclohexanedicarboximide, 1,2,3,6-tetrahydrophthalimide, 1,2,3,4-tetrahydrophthalimide, 3,4,5,6-tetrahydro Phthalimide, 1,8-naphthalimide, 2,3-naphthalenedicarboximide, cycloheximide, N-chlorosuccinimide, N-bromosuccinimide, N-iodosuccinimide, N- (methoxycarbonyl) maleimide, N- ( Imides such as hydroxy) maleimide and N- (carbamoyl) maleimide.

Further, N- (trimethylsilyl) maleimide, N- (trimethylsilyl) succinimide,
(Trimethylsilyl) citraconimide, N- (trimethylsilyl) -2-butene-2,3-dicarboximide, N- (trimethylsilyl) -1-cyclopentene-
1,2-dicarboximide, N- (trimethylsilyl) -3,4,5,6-tetrahydrophthalimide, N
-(Trimethylsilyl) succinimide, N- (triethylsilyl) maleimide, N- (tri-n-propylsilyl) maleimide, N- (tri-n-butylsilyl) maleimide, N- (tri-n-hexylsilyl) maleimide, N -(Tribenzylsilyl) maleimide, N- (n
-Butyldimethylsilyl) maleimide, N- (t-butyldimethylsilyl) maleimide, N- (dimethylzexylsilyl) maleimide, N- (n-octyldimethylsilyl) maleimide, N- (n-octadecyldimethylsilyl) maleimide, N- (benzyldimethylsilyl) maleimide, N- (methyldibutylsilyl) maleimide,
N- (phenyldimethylsilyl) maleimide, N- (p
-Methoxyphenyldimethylsilyl) maleimide, N-
(P-toluyldimethylsilyl) maleimide, N- (triphenylsilyl) maleimide, N- (tributyltin) maleimide, N- (trioctyltin) maleimide, N- (diisobutylaluminum) maleimide, N
Metal imides such as-(diethylaluminum) maleimide, mercury maleimide, silver maleimide, calcium maleimide, potassium maleimide, sodium maleimide, and lithium maleimide;

Here, the metal imide is a metal imide derived from an imide, or a mixture thereof. Specifically, the imide and the IA group, IIA group, IB group, IIB
An imide compound obtained by a reaction with a metal selected from Group IIIB, Group IIIB and Group IVB. The method for synthesizing the metal imide compound is not particularly limited, and can be synthesized by a known method. For example, imide compounds of Group IA and IIA metals include IA and II such as lithium, butyllithium, sodium, sodium hydride, potassium hydride, methylmagnesium bromide, and butylmagnesium chloride.
It can be synthesized by reacting a group A metal compound with an imide compound. The imide compounds of IB and IIB metals can be synthesized by reacting IB and IIB metal compounds such as silver nitrate, silver chloride and mercury chloride with imide compounds in the presence of an alkali. The imide compound of a Group IIIB or IVB metal can be obtained by reacting an imide compound with a Group IIIB or IVB metal chloride such as trimethylsilyl chloride, tributylsilyl chloride, tributyltin chloride or diethylaluminum chloride in the presence of an alkali.
Group IIB and IVB metal chlorides with IA, IIA, I
Reacting a metal imide compound of group B or IIB, or
It can be synthesized by reacting an imide compound with a IIIB or IVB group metal hydride such as tributyltin hydride or triisobutylaluminum hydride. Specifically, Polymer Journal, 24, 679
According to (1992), N- (trialkylsilyl) maleimide is synthesized by reacting maleimide or silver maleimide with a trialkylsilyl chloride in the presence of a tertiary amine compound, followed by distillation or recrystallization. Also, J
ournalof Organic Chemistr
According to y, 39, 21 (1974), silver maleimide is synthesized by reacting maleimide and silver nitrate in ethanol / dimethyl sulfoxide in the presence of caustic soda.

The pyrrole-containing compound may be any compound as long as it has a pyrrole ring structure.
Although not particularly limited, for example, pyrrole, 2,5-dimethylpyrrole, 3,4-dimethylpyrrole, 2,4-dimethyl-3-ethylpyrrole, 3,4-dichloropyrrole, 2,3,4,5- Tetrachloropyrrole, 2-acetylpyrrole, 3-acetyl-2,4-dimethylpyrrole, pyrrole-2-carboxylic acid, pyrrole-2-carboxaldehyde, ethyl-2,4-dimethyl-5- (ethoxycarbonyl)- 3-pyrrole-propionate, pyrrole such as ethyl-3,5-dimethyl-2-pyrrolecarboxylate, tetrahydroindole, lithium pyrrolide, sodium pyrrolide, potassium pyrrolide, cesium pyrrolide, diethylaluminum pyrrolide, ethylaluminum dichloride Pyrrolide, aluminum tripyrolide,
Diisobutylaluminum pyrrolide, sodium-2,
5-dimethylpyrrolide, potassium-2,5-dimethylpyrrolide, cesium-2,5-dimethylpyrrolide, diethylaluminum-2,5-dimethylpyrrolide, ethylaluminum bis (2,5-dimethylpyrrolide), Metal pyrrolides such as aluminum tris (2,5-dimethylpyrrolide) and diisobutylaluminum-2,5-dimethylpyrrolide.

The ether compound may be any compound having an ether bond, and is not particularly limited. Examples thereof include diethyl ether, dibutyl ether, tetrahydrofuran, pyran, dimethoxyethane, diethoxyethane, polyethylene glycol, and the like. Polypropylene glycol and the like. Of these, maleimide, N- (trimethylsilyl) maleimide, pyrrole, 2,5-dimethylpyrrole, and dimethoxyethane are preferably used from the viewpoint of activity. In addition, these hetero element-containing organic compounds can be used alone or in combination of two or more.

In the present invention, the mixing ratio of (A) the chromium compound, (B) the alkyl metal compound and (C) the organic compound containing a hetero element, which is used as required, is (A)
The (B) alkyl metal compound is usually 0.1 to 10,000 equivalents, preferably 3 to 3,000 equivalents, more preferably 10 to 2,000 equivalents to 1 mol of the chromium compound.
It is 0 equivalent. The amount of the (C) hetero element-containing organic compound to be used as needed is determined according to (A) chromium compound 1
It is usually 0.1 to 1,000 equivalents, preferably 0.5 to 500 equivalents, more preferably 1 to 30 equivalents, per mol.
It is 0 equivalent.

The chromium-based catalyst of the present invention is prepared by bringing the above-mentioned (A) chromium compound, (B) alkyl metal compound and, if necessary, (C) a hetero element-containing organic compound as raw materials into contact with each other in a solvent. it can. The contacting method is not particularly limited. For example, a catalyst is prepared by contacting (A) a chromium compound, (B) an alkyl metal compound, and (C) a hetero element-containing organic compound in the presence of ethylene as a trimerization reaction raw material. A method in which a trimerization reaction is started simultaneously with the contact, or a catalyst is prepared by previously contacting (A) a chromium compound, (B) an alkyl metal compound and (C) a hetero element-containing organic compound, and then contacting with ethylene. A method of performing a trimerization reaction is employed. The order of mixing these raw materials is not particularly limited.

The concentration of the chromium compound in preparing the catalyst system is not particularly limited, but is usually 0.001 to 100 mmol, preferably 0.01 to 10 mmol per liter of the solvent. used. Further, as the solvent used here, for example,
Butane, pentane, hexane, heptane, octane, isooctane, nonane, decane, cyclopentane, cyclohexane, methylcyclohexane, cyclooctane, aliphatic hydrocarbons such as decalin, benzene, toluene, xylene, ethylbenzene, cumene, chlorobenzene, dichlorobenzene And chlorinated hydrocarbons such as methylene chloride, chloroform, carbon tetrachloride, dichloroethane and the like. Further, the olefin itself as a reaction raw material or a reaction product such as butene,
Olefins such as hexene, octene, decene, dodecene and the like can also be used as solvents. These solvents can be used alone or in combination of two or more. Here, for the purpose of controlling the catalyst concentration at the time of preparing the catalyst, it may be concentrated or diluted as necessary.

The temperature at which the chromium compound, the alkyl metal compound and the hetero element organic compound are brought into contact is usually -100 to 250 ° C, preferably 0 to 200 ° C.
The preparation time of the catalyst system is not particularly limited, and is usually 0 minutes to 24 hours, preferably 0 minutes to 2 hours. It is desirable that all operations for preparing the catalyst be performed while avoiding air and moisture. Further, it is preferable that the catalyst preparation raw material and the solvent are sufficiently dried. According to the present invention, the chromium-based catalyst prepared as described above, if desired, further chlorine, bromine, iodine, butyl chloride, amyl chloride, hexyl chloride, heptyl chloride, octyl chloride, nonyl chloride, decyl chloride, Lauryl chloride, methyl bromide, propyl bromide, butyl bromide, amyl bromide, hexyl bromide, ethylhexyl bromide, nonyl bromide, cetyl bromide, dibromomethane, dichloroethane, dibromoethane, dichlorobutene, cyclohexyl bromide, chloroform, hydrocarbon tetrachloride, chlorobenzene, dichloromethane Chlorobenzene, bromobenzene, dibromobenzene, sodium chloride, potassium chloride, cesium chloride, magnesium chloride, zinc chloride, zinc bromide, zinc iodide, boron trichloride, tribromide Iodine, aluminum trichloride, aluminum tribromide, silicon tetrachloride, germanium tetrachloride, germanium tetrabromide, stannous chloride, stannic chloride, tin iodide, phosphorus trichloride, phosphorus pentachloride, antimony trichloride Antimony pentachloride, antimony tribromide, antimony trifluoride, antimony pentafluoride, dimethylaluminum chloride, dimethylaluminum bromide, dimethylaluminum iodide, diethylaluminum chloride, diethylaluminum bromide, diethylaluminum iodide, ethylaluminum dichloride, Ethyl aluminum dibromide, ethyl aluminum diiodide, diisopropyl aluminum chloride, diisobutyl aluminum chloride, isobutyl aluminum dichloride, dihexyl aluminum Chloride, dicyclohexyl aluminum chloride, dioctyl aluminum chloride, methyl aluminum sesquichloride, ethyl aluminum sesquichloride, butyl aluminum sesquichloride, trimethylsilyl chloride, trimethylsilyl bromide, dimethylsilyl dichloride, trimethylsilyl trichloride,
Halides such as phenylsilyl trichloride, diphenylsilyl dichloride, methyldichlorosilane, tributyltin chloride, dibutyltin dichloride, butyltin trichloride, triphenyltin chloride, diphenyltin dichloride, phenyltin trichloride, and tris (2-fluorophenyl ) Boron, tris (3-fluorophenyl) boron, tris (4-fluorophenyl) boron, tris (2,4-difluorophenyl) boron, tris (2,5-difluorophenyl) boron,
Tris (2,6-difluorophenyl) boron, tris (2,4,5-trifluorophenyl) boron, tris (2,4,6-trifluorophenyl) boron, tris (pentafluorophenyl) boron, bis (penta Fluorophenyl) zinc, tris (pentafluorophenyl) aluminum, tetrakis (pentafluorophenyl) germanium, tetrakis (pentafluorophenyl) tin, tris (4-trifluoromethylphenyl)
A Lewis acid such as boron is added to serve as a chromium-based catalyst. Effects such as improvement of catalytic activity and suppression of by-product of polymer are recognized by the coexistence of halide and Lewis acid.

The trimerization reaction of ethylene is carried out using the chromium-based catalyst thus prepared. The amount of the chromium-based catalyst used in the present invention is not particularly limited, but is usually 0.001 micromol to 100 mmol, preferably 0.01 micromol, per liter of the trimerization reaction solution diluted with the solvent. Used at a concentration of 〜１０10 mmol. If the catalyst concentration is lower than this, sufficient activity cannot be obtained. Conversely, if the catalyst concentration is higher than this, catalyst activity does not increase and it is not economical.

The temperature of the trimerization reaction in the present invention is usually from -100 to 250 ° C, preferably from 0 to 200 ° C.
It is. The reaction pressure is usually 0 to 300 kg / c in absolute pressure.
m ² , preferably 0 to 150 kg / cm ² .
The reaction time depends on the temperature and the pressure and cannot be determined unconditionally, but is usually 5 seconds to 6 hours. Further, ethylene may be continuously supplied so as to maintain the above-mentioned pressure, or may be sealed at the above-mentioned pressure at the start of the reaction to cause a reaction. Ethylene, which is a raw material gas, may contain a gas inert to the reaction, for example, nitrogen, argon, helium, or the like. In addition, all operations of the trimerization reaction
It is desirable to avoid air and moisture. Further, it is preferable that ethylene is sufficiently dried.

The reaction product solution obtained by trimerizing ethylene in this manner is mixed with water, methanol, ethanol,
Alcohols such as propanol, butanol, hexanol, octanol, 2-ethylhexanol, cyclohexanol, ethylene glycol, propylene glycol, and benzyl alcohol; phenols such as phenol and cresol; and acetic acid, propionic acid, and octylic acid;
The chromium-based catalyst is deactivated by adding a carboxylic acid such as 2-ethylhexanoic acid or a deactivator such as aqueous ammonia or an aqueous sodium hydroxide solution.

In the present invention, the reaction product liquid obtained by deactivating the catalyst in this manner is first kept at 100 ° C. or higher, and water is introduced as it is to contain the chromium-based catalyst. The metal component is deashed. Here, the demineralization treatment of the metal component contained in the chromium-based catalyst means that metals such as chromium and aluminum contained in the chromium-based catalyst in the reaction product solution are extracted with water, and the water is used as the reaction product solution. Separation means removing the metal component from the reaction product liquid. The contact between the reaction product and water may be performed using a known extraction device. For example, it is preferable to use a combination of a stirring tank and a stationary separation tank. These devices may be single-stage or multi-stage, and may be batch type or continuous type.

In the present invention, the amount of water to be added is 20 to 200% by volume, preferably 30 to 200% by volume, based on the reaction product solution.
% By volume. When the amount of water added is less than 20% by volume based on the reaction product solution, the metal components contained in the reaction product solution cannot be sufficiently removed. When the amount of water added is more than 200% by volume based on the reaction product solution, the extraction efficiency does not increase, and the size of the extraction device increases, so that the economic efficiency is lost. In the addition of the water, it is important to prevent the metal component in the catalyst from being precipitated in the form of a hydroxide, that is, chromium hydroxide or aluminum hydroxide. In order to prevent the precipitation of these hydroxides, acidic compounds such as sulfuric acid and nitric acid are added to water,
Alternatively, it is desirable to coexist an alkaline compound such as sodium hydroxide or potassium hydroxide. Of these, sodium hydroxide and potassium hydroxide are preferably used in terms of ease of handling and economy. The amount of the alkaline compound to be added is not particularly limited, but the pH of the aqueous solution is preferably 11 or more, more preferably PH1
It is added so that it becomes 2 or more. In the case of adding an alkaline compound, if the pH of the aqueous solution is less than 11, chromium precipitates as a hydroxide, and chromium cannot be substantially deashed.

Here, it is necessary to maintain the temperature of the reaction product liquid after the deactivation treatment at 100 ° C. or higher. The temperature of the reaction product liquid at the time of the deashing treatment is 100 to 180 ° C, preferably 100 to 150 ° C. If the temperature of the reaction product solution is lower than 100 ° C, the polymer by-produced in the trimerization reaction precipitates in a solid state, and clogs the reactors, control valves, pipes, and other equipment during the deactivation treatment, and causes Cause trouble. In addition, since most of the metal component of the chromium-based catalyst used is contained in the solid polymer, the metal component is not removed from the solid polymer, but remains in the reaction product liquid. When the temperature of the reaction product solution is higher than 180 ° C., the polymer is substantially completely dissolved, no further effect is exhibited, and it is not economical. The amount of polymer produced as a by-product of this trimerization reaction is not uniform depending on the reaction conditions, but is usually 0.1 to 1-hexene production.
By keeping the reaction product liquid at 100 ° C. or higher, the reaction product is melted, stable operation can be continued, and metal components in the polymer can be efficiently removed. The pressure of the demineralization treatment is not particularly limited as long as the reaction product liquid can maintain a liquid state, but is usually 2 kg / cm ² or more.
It is preferably at least 5 kg / cm ² . The time of the demineralization treatment depends on the temperature and the pressure, and cannot be determined unconditionally, but is usually 5 seconds to 1 hour.

In the demineralization treatment of the present invention, the demineralization treatment is performed by heating as described above and further stirring. Here, since the demineralization treatment is the extraction of the metal component in the reaction product solution with water, the dispersion of water droplets, that is, the size of the contact area is an important factor. In this stirring, in order to increase the contact interface area between the reaction product liquid and water and to improve the deashing efficiency, 1 KW / unit volume of the mixture of the reaction product liquid and water is used.
Stir the treatment system with the required stirring power of m ³ or more. Preferably, it is 2-100 KW / m ³ . When the power required for stirring is smaller than 1 KW / m ³ , the metal components in the reaction product liquid are not sufficiently demineralized. Conversely, 100KW / m
If it is larger than ³ , the contact area does not increase and it is not economical.

After introducing water into the reaction product under the heating condition and stirring the mixture, the mixture of the reaction product and water is
It is allowed to stand and separated into two phases, an oil phase and an aqueous phase. The standing time of 1 minute to 1 hour is usually sufficient. After standing, oil and water are separated to complete the demineralization process.

In the present invention, after the completion of the trimerization reaction, a quenching agent is introduced into the reaction product to deactivate the chromium-based catalyst (a chromium-based catalyst deactivating step). Ash treatment is performed (deashing step of the catalyst), and 1-hexene and the solvent are separated and recovered by distillation (distillation step of 1-hexene and the solvent). The step of recovering unreacted ethylene may be before or after the deactivation step. The temperature in the unreacted ethylene recovery step, the catalyst deactivation step, and the fractionation step of 1-hexene and the solvent are not particularly limited. The recovered unreacted ethylene and solvent are recycled to the trimerization reaction system as needed. In this reaction, a small amount of 1 carbon atom is added together with 1-hexene by the ethylene trimerization reaction.
0 and 14 high boiling olefins are formed. This high-boiling olefin can be used to obtain various desired high-boiling olefins by multistage distillation. These high-boiling olefins may be recycled as a solvent to the trimerization reaction system if necessary.

[0040]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which are only for illustrating the outline of the present invention and the present invention is not limited to these Examples. . Example 1 14.5 mg (0.15 mg) of maleimide was placed in a 1-liter Schlenk tube.
mmol) was dissolved in 400 ml of dry cyclohexane, and 5.0 ml of a 0.01 mol / l chromium (III) tris (2-ethylhexanoate) / cyclohexane solution was added and mixed. 11.0 ml of 0.12 mol / l triethylaluminum / cyclohexane solution
And a mixture of 5.0 ml of a 0.04 mol / l ethylaluminum dichloride / cyclohexane solution, and the mixture was stirred at room temperature for 1 hour to prepare a catalyst solution.

As a reaction apparatus, an apparatus in which a trimerization reactor (1 l) and a deashing tank (2 l) were connected by an overflow pipe was used.

A 1 l stainless steel pressure-resistant reaction vessel equipped with a thermometer, a catalyst solution feed pipe and
After vacuum drying under heating at ℃, the atmosphere was sufficiently replaced with nitrogen gas. The entire amount of the catalyst solution was charged in a container. Stirring speed 1,0
After adjusting to 00 rpm and heating the reaction vessel to 120 ° C., ethylene gas was blown so that the absolute pressure in the reaction vessel became 40 kg / cm ^2, and the ethylene trimerization reaction was started. Thereafter, the introduction was continued so as to maintain the pressure, and the reaction was carried out for 10 minutes while maintaining these reaction conditions. 1
After 0 minutes, the catalyst was deactivated by forcing water into the reaction vessel with nitrogen and the reaction was stopped. A part of the reaction solution was extracted, and the product contained in the reaction solution was analyzed by gas chromatography. As a result, the catalytic activity was 93.
1 kg / g-Cr-hour, olefin selectivity is C4;
0.1% by weight, C6; 90.3% by weight, C8; 0.3% by weight, C10; 7.6% by weight, C12 or higher olefin; 1.7% by weight.

The reaction product liquid obtained by the deactivation treatment is 100
While maintaining the temperature in ° C., a thermometer, a sampling tube, a stirrer, four baffles (1.1 cm in width) and four fan turbines (blade diameter 7
cm, ribbon width 1.2 cm, mounting angle of stirring blade 90
The pressure was fed to a stainless steel pressure-resistant reaction vessel (tank diameter: 10.5 cm, tank height: 24 cm) equipped with an internal volume of 2 l. A necessary amount of cyclohexane was newly added so that the reaction product solution became 700 ml, and the mixture was heated and stirred at a predetermined temperature shown in Table 1.
Next, aqueous sodium hydroxide solution 210 adjusted to PH12
ml, and decalcification was performed under the conditions shown in Table 1. High-frequency plasma emission spectroscopy (IC
P), and the demineralization rate of the metal component in the reaction product solution (weight% of metal contained in the reaction product solution after the demineralization process with respect to the metal contained in the reaction product solution before the demineralization process) Calculated. Table 1 shows the results.

Example 2 A trimerization reaction, a deactivation treatment and a demineralization treatment were carried out in the same manner as in Example 1 except that a metal component in the reaction product solution was subjected to a demineralization treatment under the conditions shown in Table 1. . Table 1 shows the results.

Example 3 A 1-liter stainless steel pressure-resistant reaction vessel equipped with a thermometer, a catalyst solution feed tube, and a stirrer was heated and vacuum-dried at 90 ° C., and then sufficiently replaced with nitrogen gas. 0.01mol
/ L of chromium (III) tris (2-ethylhexanoate) / cyclohexane solution 5.0 ml, 0.10 mo
1.5 ml of 1 / l 2,5-dimethylpyrrole and 350 ml of cyclohexane were charged into the body side of the reaction vessel, and sufficiently replaced with ethylene. On the other hand, 0.50m
3.0 ml of an ol / l triethylaluminum / cyclohexane solution and 1.0 ml of a 0.10 mmol / l germanium tetrachloride / cyclohexane solution were charged.

After heating the reaction vessel to 120 ° C. and adjusting the stirring speed to 1,000 rpm, ethylene was introduced into the catalyst feed tube, and a mixed solution of triethylaluminum and diethylaluminum chloride was introduced into the reaction vessel by the ethylene pressure. Then, the ethylene trimerization reaction was started. Ethylene gas was blown in so that the absolute pressure in the reaction vessel became 40 kg / cm ^2, and thereafter, the introduction was continued so as to maintain the above pressure, and the ethylene trimerization reaction was carried out for 30 minutes while maintaining these reaction conditions. Was performed. After 30 minutes, the reaction was stopped by injecting an aqueous sodium hydroxide solution into the reaction vessel with nitrogen to deactivate the catalyst. A part of the reaction solution was extracted, and the product contained in the reaction solution was analyzed by gas chromatography. As a result, the catalyst activity was 66.6 kg / g-Cr-hour, and the olefin selectivity was C4; 0.1% by weight, C6; 95.0% by weight, C8;
0.5% by weight, C10; 3.7% by weight, C12 or more olefin; 0.7% by weight.

A deashing treatment was performed in the same manner as in Example 1 except that the ethylene trimerization reaction and the deactivation treatment were performed. Table 1 shows the results.

Example 4 A Schlenk tube equipped with a stirrer was heated and vacuum dried, and then sufficiently purged with nitrogen gas.
l of 98.3 ml of a triisobutylaluminum / cyclohexane solution was added thereto, and cooled in an ice water bath. Under ice cooling, 259 mg of water was slowly added dropwise with stirring, and the stirring was maintained for 1 hour to synthesize a 0.195 mol / l isobutylaluminoxane / cyclohexane solution.

The above 0.195 mol was added to a 1-liter Schlenk tube.
/ L isobutylaluminoxane / cyclohexane solution 3
0.8 ml (6.0 mmol in terms of Al), 0.27 g (3.0 mmol) of 1,2-dimethoxyethane and 550 ml of dry cyclohexane are added, and then 0.1 mol / l.
2.0 ml of a chromium (III) tris (2-ethylhexanoate) / cyclohexane solution was mixed and stirred at room temperature for 1 hour to prepare a catalyst solution.

A 1 l stainless steel pressure-resistant reaction vessel equipped with a thermometer, a catalyst solution feed pipe and
After vacuum drying under heating at ℃, the atmosphere was sufficiently replaced with nitrogen gas. The entire amount of the catalyst solution was charged in a container. Stirring speed 1,0
After adjusting to 00 rpm and heating the reaction vessel to 100 ° C., ethylene gas was blown so that the absolute pressure in the reaction vessel became 35 kg / cm ^2, and the ethylene trimerization reaction was started. Thereafter, the introduction was continued so as to maintain the pressure, and the reaction was carried out for 30 minutes while maintaining these reaction conditions. 3
After 0 minute, the reaction was stopped by injecting an aqueous sodium hydroxide solution into the reaction vessel with nitrogen to deactivate the catalyst. A part of the reaction solution was extracted, and the product contained in the reaction solution was analyzed by gas chromatography. As a result, the catalyst activity was 5.2 kg / g-Cr-hour, the selectivity of olefin was C4; 1.1% by weight, C6; 86.8% by weight, C8; 5.2% by weight, C10; 6.0. % By weight, C
12 or more olefins; 0.9% by weight.

A deashing treatment was carried out in the same manner as in Example 1, except that the ethylene trimerization reaction and the deactivation treatment were carried out. Table 1 shows the results.

Comparative Examples 1 to 4 A trimerization reaction, a deactivation treatment and a demineralization treatment were carried out in the same manner as in Example 1, except that the metal components in the reaction product solution were subjected to the demineralization treatment under the conditions shown in Table 1. Done. Table 1 shows the results.

[0053]

[Table 1]

[0054]

According to the present invention, in the method for producing 1-hexene by trimerizing ethylene, the metal component of the chromium-based catalyst used in the ethylene trimerization reaction is demineralized after the completion of the reaction. Without removing by-product polymers to the outside of the system and without clogging the reactor, control valves, piping, pumps, etc. during the demineralization process, furthermore, the metal components of the used catalyst can be extremely separated from the reaction product liquid. It can be removed to a low concentration.

Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical indication location C07C 2/32 9734-4H C07C 2/32 7/148 9734-4H 7/148 // C07B 61/00 300 C07B 61/00 300

Claims (2)

[Claims] In a method for producing 1-hexene by trimerizing ethylene in the presence of a chromium-based catalyst, the chromium-based catalyst is deactivated after completion of the trimerization reaction. While maintaining the temperature at a temperature of 20 to 200% by volume of water with respect to the reaction product liquid into the treatment system,
1-Hexene, further comprising a demineralization treatment step of stirring the treatment system with a required stirring power of 1 KW / m ³ or more per unit volume to remove a metal component contained in the chromium-based catalyst from the reaction product liquid. Manufacturing method. 2. The method for producing 1-hexene according to claim 1, wherein the chromium-based catalyst is a catalyst comprising at least (A) a chromium compound and (B) an alkyl metal compound.