JPH0441440A - Dimerization of lower olefin - Google Patents

Abstract

PURPOSE:To obtain a dimer having low branch content in high activity by dimerizing a lower olefin using an Ni compound and an organic alkylaluminum as catalysts in the presence of a quaternary phosphonium salt. CONSTITUTION:The dimerization of a lower olefin (especially butene) is carried out in the presence of an Ni compound (e.g. nickel acetate, nickel chloride and nickel acetylacetonate), an organic alkylaluminum (e.g. trimethylaluminum) and a compound of formula (R1 to R3 are 1-20C alkyl or aryl; R4 is >= 4C straight-chain hydrocarbon group; X is Cl, Br or I) (e.g. tetraethylphosphonium chloride). The amount of the compound of formula is preferably 1-5 mol per 1 mol of the Ni compound and the reaction is preferably carried out by mixing the Ni compound with the compound of formula, mixing the mixture with the organic alkylaluminum and olefin and reacting the components at 10-80 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for dimerizing lower olefins in the presence of a catalyst. Dimers of lower olefins such as ethylene, propylene, or butene are industrially useful compounds as raw materials for surface active and plasticizing materials.

[Conventional technology]

As methods for dimerizing lower olefins, methods using anionic polymerization catalysts, cationic polymerization catalysts, or coordination polymerization catalysts have been known for a long time.

Among these, Ziegler catalysts containing nickel are preferably used because they are excellent in activity and dimer quality. For example, 02-C
Method for quantifying α-olefin No. 4 (Japanese Patent Publication No. 46-3
161), Method for dimerizing butene using alkylaluminum chloride and fatty acid nickel compound as catalyst (JP-A-5492901, JP-A No. 54-157510)
, 55-7226), etc. are disclosed.

It is also known that trivalent phosphorus compounds are effective as a third additive to improve activity, for example,
A method for underpolymerizing propylene using an alkyl aluminum halide, a divalent nickel compound, a divalent cobalt compound, and a trivalent phosphorus compound as catalysts (Special Publications Publication No. 4)
6-3162), alkyl aluminum halide,
A method for underpolymerizing propylene using a nickel compound or cobalt compound and a trivalent phosphorus compound as a catalyst (
Japanese Patent Publication No. 47-22807) is disclosed. Furthermore,
A method for dimerizing butene using a catalyst prepared by adding halogenated phenol and water as a fourth addition to triethylaluminum, a nickel compound, and a trivalent phosphorus compound (Japanese Patent Application Laid-open No. 169433/1983), and also in the above method. Butene dimerization method using a catalyst containing fluorinated isopropanol as a fourth additive
158225, Japanese Patent Application Laid-Open No. 0F-221335).

[Problem to be solved by the invention]

Compounds obtained by lower polymerization of lower olefins are obtained as branched dimers or mixtures of lower polymers, and these are mainly used as raw materials for alkylphenols, which are raw materials for surfactants, or are converted into alcohols by oxidation. Furthermore, as an ester with carboxylic acid, it is used as a plasticizer for vinyl chloride resin, etc. but,
Low polymers with many branches have poor biodegradability, or
It has also been pointed out that plasticizers used in food-grade vinyl chloride resin films are taken into living organisms, so a method to produce highly active dimers or low polymers with a low branching ratio is needed. It was wanted.

[Means to solve the problem]

The present inventors have diligently studied methods for producing highly active dimers or low polymers with a low branching ratio, and have maintained the degree of branching by coexisting a quaternary phosphonium salt with a Ni-based Ziegler catalyst. However, they discovered that polymerization was possible with even higher activity and completed the present invention. That is, the present invention is a method for dimerizing lower olefins using a nickel compound and an organic alkyl aluminum as a catalyst, which is characterized in that a quaternary phosphonium salt is allowed to coexist.

The process of the invention is used for the dimerization or oligomerization of lower olefins such as ethylene, propylene or butene. Among these, it is preferably used for butene dimers.

When using the method of the present invention using C1 olefin as a raw material, butene-1, cis-butene-2, trans-butene-1
Since dimers having almost the same degree of branching are obtained from the two n-butenes, these n-butenes can be used as raw materials without being separated. The degree of branching here refers to the number of methyl groups branched to the main chain hydrocarbon, such as n-octane, 2-methylhebutane, and 3-methyl hebutane.
, 4-dimethylhexane have a degree of branching of 0.1 and 2, respectively.

In addition, in the method of the present invention, the reaction system contains impurities in the raw material olefin, such as paraffin hydrocarbons such as methane, ethane, and butane, sulfur, inert gases such as nitrogen and carbon dioxide, or hydrogen. can also be implemented.

As the nickel compound or organoalkyl aluminum used in the method of the present invention, compounds known to those skilled in the art are used. Examples of nickel compounds include fatty acid nickel compounds such as nickel acetate, nickel naphthenate, nickel octoate, nickel 2-ethylhexanoate, and nickel benzoate, and halogenated nickel chloride, nickel bromide, and nickel iodide. Examples include nickel, easily available nickel acetylacetonate, nilakerosene, nickelcarbonyl, and the like.

Further, examples of organic alkylaluminum compounds include trimethylaluminum, triethylaluminum, tri-n-propylaluminum, tri-1sO-propylaluminum, tri-n-butylaluminum, tri-1so-
trialkylaluminum such as butylaluminum, tri-tert-butylaluminum, dimethylaluminum chloride, methylaluminum dichloride,
Diethylaluminum chloride, diethylaluminium iodide, ethylaluminum dichloride, ethylaluminum dichloride, di-n-propylaluminum chloride, n-propylaluminum dichloride, di-1so-propylaluminum chloride, 1
so-propylaluminum dichloride, dibutylaluminum chloride, n-butylaluminum dichloride, di-1so-butylaluminum chloride, di-1so-butylaluminum bromide, 1so-
Examples include alkylaluminum halides such as butylaluminum dichloride, di-tert-butylaluminum chloride, and tert-butylaluminum dichloride.

The amount of the nickel compound used in the method of the present invention is in the range of 0.000001 to 0.001 mole, more preferably 0.00002 to 0.00 times the olefin as the raw material.
The range is 0.2 mole times.

Furthermore, if the amount of aluminum alkyl used in the method of the present invention is too large, the yield will improve, but the proportion of multiple polymers will increase, which is not preferable. Therefore, the amount of organic alkyl aluminum used is 2 to 1
The amount is preferably 5 to 50 times by mole, more preferably 5 to 50 times by mole.

The quaternary phosphonium used in the method of the invention (wherein
R1, R2, R3, and R4 are an alkyl group or an aryl group having 1 to 20 carbon atoms, and X represents a chlorine, bromine, or iodine atom. Examples of such quaternary phosphonium salts are, for example, tetraethylphosphonium chloride, tetraethylphosphonium bromide, tetraethylphosphonium iodide, methyltriphenylphosphonium chloride, ethyltriphenylphosphonium bromide, n-propylphosphonium iodide. Among these quaternary phosphonium salts, quaternary phosphonium salts in which at least one linear hydrocarbon having a carbon number of 4 or more is coordinated are preferable, such as tetra n-butylphosphonium chloride, tetra n- Butylphosphonium bromide, tetra n-butylphosphonium iodide, n-pentyltriphenylphosphonium chloride, n-pentyltriphenylphosphonium bromide, n-pentyltriphenylphosphonium iodide, n-hebutyltriphenylphosphonium chloride, n-hebutyl Triphenylphosphonium bromide, n-hebutyltriphenylphosphonium iodide, 2-ethylhexyltriphenylphosphonium chloride, n-lauryltriphenylphosphonium chloride, n-lauryltriphenylphosphonium bromide, n-lauryltriphenylphosphonium iodide, etc. A quaternary phosphonium salt in which at least one linear hydrocarbon having 6 to 15 carbon atoms is coordinated is more preferably used.

Further, a method of simultaneously using a trivalent phosphine and a 1-halogen compound of a linear hydrocarbon having 4 or more carbon atoms is also included in the method of the present invention. Examples of these include triphenylphosphine and n-pentyl chloride, triphenylphosphine and n-hebutyl chloride, triphenylphosphine and n-hebutyl chloride, methyldiphenylphosphine and n-octyl bromide, and triphenylphosphine and n-nonyl iodine. Examples include dydo, tricyclophosphine and n-lauryl chloride.

Furthermore, among these, linear halogenated hydrocarbons having 6 to 15 carbon atoms are preferred, and chlorides are more preferred.

If the amount of these quaternary phosphonium salts used is too small, the effect will be small, but if added in excess, it will have a negative effect on the reaction such as a decrease in yield, so The amount is in the range of 10 times the mole, preferably 1 to 5 times the mole. Also, these fourth
The class phosphonium salts can be preferably used alone or in combination.

The nickel compound, organoalkyl aluminum, or quaternary phosphonium salt used in the method of the present invention may be fed to the reactor as is, but they may be fed to the reactor as they are, but they may be fed to the reactor as they are, but they may be fed to the reactor as they are, or they may be mixed with an aliphatic hydrocarbon such as hexane, heptane, octane, or decane. Or alicyclic hydrocarbons such as cyclohexane, decalin, or aromatic hydrocarbons such as toluene, benzene, xylene, or products 04-CI6
In addition, in the method of the present invention, the olefin, nickel compound, organoalkyl aluminum, and quaternary phosphonium salt may be mixed in any order; It is preferable to mix the compound and the quaternary phosphonium salt before use. In this case, preferable results can be obtained even if these and the organic alkyl aluminum and olefin are mixed in any order.

In the present invention, the lower the reaction temperature, the smaller the degree of branching, which is preferable, but the reaction rate becomes slower. On the other hand, if the reaction temperature is raised (the reaction rate becomes faster, but if it is too high, the catalyst becomes unstable and the yield decreases, which is not preferable. ℃ range.

The reaction pressure in the present invention is not particularly limited, and the reaction is carried out under the vapor pressure of the olefin as a raw material, a solvent in which the catalyst is dissolved, or the like.

Further, the method of the present invention can be carried out in a batch method, a semi-flow method, or a flow method.

〔Example〕

The method of the present invention will be explained in detail by way of examples.

Example 1 Nickel octanoate J was placed in an autoclave with an internal volume of 200 d.
Shiku0,06mmol) # Yohi n-haepchi!
Retriphenylphosphonium bromide (0.12 wm
ol) containing heptane and ethyla! Heptane containing reminium dichloride (0.95 mmol) was prepared at room temperature to prevent air from getting mixed in, and while stirring, 45.3 g (810 mmol) was added from a pressure-resistant container.
of butene-1 was injected with nitrogen. After reacting at 50°C for 4 hours, it was cooled, the unreacted raw material olefin was evacuated, the recovered reaction solution was treated with a 10% sulfuric acid aqueous solution to inactivate the catalyst, and the liquid phase was separated and subjected to gas chromatography. It was analyzed in

As a result, the conversion rate of butene-1 was 68.3%', and the selectivity of cm olefin and C+t olefin was 90%, respectively.
．． 5% and 8.2%, and the degree of branching of C, olefin was 1.32.

Examples 2 to 6 The reaction was carried out in the same manner as in Example 1, except that the types and amounts of the olefin, nickel compound, and quaternary phosphonium salt, and the reaction temperature and reaction time were changed as shown in Table 1. Ta. The results are shown in Table 1.

Comparative Examples 1 to 3 Examples 1 to 3 except that no quaternary phosphonium salt was used
The reaction was carried out in the same manner as in 3. The results are shown in Table 1.

Examples 7 to 10 A trivalent phosphine and a halogenated hydrocarbon were used instead of the quaternary phosphonium salt, and the type, amount, and reaction temperature of the olefin and nickel compound were changed to those shown in Table 1. The reaction was carried out in the same manner as in Example 1. The results are shown in Table 2.

Comparative Examples 4-5 A reaction was carried out in the same manner as in Example 7 except that trivalent phosphine or halogenated hydrocarbon was not used. The results are shown in Table 2.

Comparative Examples 6 to 8 Reactions were conducted in the same manner as in Example 6 except that trivalent phosphine or halogenated hydrocarbon was not used. The results are shown in Table 2.

〔Effect of the invention〕

By coexisting a quaternary phosphonium salt in the present invention, it is possible to obtain a dimerized product with an activity improvement of 15% or more while maintaining the degree of branching, which is an industrially advantageous method.

Patent applicant Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 1. A method for dimerizing lower olefins using a nickel compound and an organoalkyl aluminum as a catalyst,
A method for dimerizing lower olefins, which comprises coexisting a quaternary phosphonium salt. 2. Quaternary phosphonium salts have general formulas, ▲mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R1, R2, and R3 are alkyl groups or aryl groups having 1 to 20 carbon atoms, and R4 is a straight chain carbon The method according to claim 1, wherein the number is 4 or more and X represents a chlorine, bromine, or iodine atom.