JPS6340413B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a new nickel compound. In Japanese Patent Application No. 55-19649, the present inventors have described a novel divalent nickel compound, a method for its preparation, and its use as a component of a catalyst composition for the oligomerization of olefins. The nickel compound described in the above patent application corresponds to the general formula (R ₁ COO) (R ₂ COO)Ni [where R ₁ is, for example, alkyl, cycloalkyl, alkenyl, aryl, aralkyl or alkaryl] a hydrocarbon residue containing at least 5 carbon atoms, preferably a hydrocarbon residue of 5 to 20 carbon atoms, such as a group, which residue may be substituted with, for example, a hydroxyl group, and R ₂ is Halogenoalkyl residue, represented by the formula CmHpXq (where m = 1, 2 or 3, p is 0 or an integer,
q is an integer, and the condition is p+q=2m+1. ) Preferably, _R2 is a halogenomethyl residue _CXnH3 -n, where X is fluorine, chlorine, bromine or iodo and n is an integer from 1 to 3]. The above-mentioned nickel compounds have a high solubility in the hydrocarbon medium, i.e. at least 0.1 g per 1 and in most cases much more than 1 g per temperature at temperatures of about 30 to 60° C. at which they will be used in the oligomerization reaction. Indicates solubility. The purpose of the present invention is to disclose a new method for producing the nickel compound. This production method involves reacting at least one (R ₁ COO) ₂ Ni compound with at least one (R ₂ COO) ₂ Ni compound in a medium containing a polar solvent, such as water and/or alcohol; then operating in the presence of a non-polar solvent, such as a hydrocarbon or halogenated hydrocarbon, which is less volatile than the polar solvent and at least a portion of which does not distill off, to distill off the polar solvent. . In this way, the hybrid compound is recovered as a solution in the non-polar solvent. If both of the nickel compounds are soluble in polar solvents, the compounds may be reacted directly in the polar solvent and then the non-polar solvent added. Particularly when the polar solvent is water, these two types of solvent may be used from the beginning of the reaction. because,
This is because the compound (R ₁ COO) ₂ Ni can be made into a solution in this way. The above-mentioned nickel compound may preferably be used in equimolar proportions, but may deviate from this value. The amount of water and/or alcohol used is not critical, but best results are obtained with the minimum amount required to dissolve the reactants at the reaction temperature. The amount of hydrocarbon phase or halogenated hydrocarbon phase used must be sufficient to ensure dissolution of the resulting hybrid salt and will therefore vary depending on the type of reactants used. A preferred amount is between 2 and 100 times the amount of water or alcohol introduced. The reaction temperature is selected depending on ease of operation.
However, the preferred mode is to reflux the reaction mixture at atmospheric pressure, above or below, until a stable coloration of the organic phase is achieved. This operation may take, for example, 5 minutes to 5 hours depending on the reflux temperature. If insoluble substances are present, they can be removed by decantation or filtration. After removing the polar solvent, the nonpolar hydrocarbon or halogenated hydrocarbon solvent can be evaporated or distilled, and the nickel compound can be isolated as a generally amorphous green solid. However, for certain applications, it can be used directly as a solution. The non-polar solvent is preferably selected from aliphatic, cycloaliphatic or aromatic hydrocarbons or mixtures thereof, or halogenated hydrocarbons, such as chlorohydrocarbons, fluorinated hydrocarbons or bromohydrocarbons. For example, pentane, peptane,
Petroleum ether, white spirit, cyclohexane, toluene, xylene, ethylbenzene,
Methylene chloride, chloroform and chlorobenzene may be used. The alcohol may contain, for example, 1 to 3 carbon atoms, such as methanol, ethanol, propanol or isopropanol. The alcohol may or may not be absolute alcohol. Higher alcohols are less desirable. Another object of the present invention is the use of divalent nickel hybrid salts as elements of catalyst compositions for oligomerization, particularly for the dimerization and trimerization of monoolefins. The catalyst composition is obtained by contacting at least one nickel hybrid salt with at least one hydrocarbyl aluminum halide. An example of a salt with the formula (R ₁ COO) ₂ Ni is ethyl-
Nickel 2-butyrate, nickel dimethyl-3.3-butyrate, nickel methyl-4-valerate, nickel heptanoate, nickel ethyl-2-hexanoate, nickel decanoate, nickel myristate, nickel palmitate, nickel dotecylbenzoate, diisopropyl Examples include nickel salicylate. Examples of salts of the formula (R ₂ COO) ₂ Ni include nickel trichloroacetate, nickel dichloroacetate, nickel monochloroacetate, nickel trifluoroacetate,
Examples include nickel monofluoroacetate, nickel tribromoacetate, nickel triiodoacetate, nickel pentafluoropropionate, nickel heptafluorobutyrate, and hydrates thereof. Preferred halogenated hydrocarbyl aluminum compounds correspond to the general formula Al ₂ RxYy [wherein
R ₁ represents a hydrocarbon group having up to 12 or more carbon atoms such as an alkyl, aryl, aralkyl, alkaryl, cycloalkyl group; Y represents a halogen such as fluorine, chlorine, bromine or iodo; and y each have a value of 2, 3 or 4, and x+y=6]. Examples of such compounds include sesquichloroethylaluminum, dichloroethylaluminum, dichloroisobutylaluminum, chlorodiethylaluminium and mixtures thereof. An example of a catalyst composition is any of the above aluminum compounds of the formula (R ₁ COO) ₂ Ni and any of the above compounds of the formula (R ₁ COO) ₂ Ni
Any one of the hybrid compounds of nickel obtained by reacting any one of the above-mentioned compounds with any one of the above-mentioned compounds. The present invention also provides for the production of monoolefins in the presence of a catalyst system as defined above, at temperatures between -20°C and +80°C, and under pressure conditions such that the reactants remain at least predominantly in the liquid or condensed phase. Another object of the present invention is a method for oligomerizing. Monoolefins which can be dimerized or oligomerized are, for example, ethylene, propylene, n-
Butene, n-pentene, is either pure or in the form of a mixture, such as from synthetic processes such as catalytic cracking or steam cracking. These monoolefins are, for example,
Between each other or with isobutene, ethylene with propylene and n-butene, and propylene with n-butene.
-butene and n-butene can each be co-oligomerized with isobutene. The concentration of the catalyst composition in the liquid phase for oligomerization reaction is usually between 5 and 500 ppm by weight expressed in nickel. The molar ratio of hydrocarbyl aluminum halide to nickel compound is usually comprised between 1:1 and 50:1, preferably between 2:1 and 20:1. Although the process may be practiced with separate charges, it shows the greatest advantage when operated continuously. In this case, a reactor having one to several reaction stages in series is used, and the components of the charged olefin and/or catalyst are introduced successively or into the first stage, or into the first stage and any one stage. Bye. Also, only one component of the catalyst mixture needs to be added to the first stage and/or the nth stage. The catalyst leaving the reactor is inactivated in known manner, for example with ammonia and/or aqueous soda and/or sulfuric acid solutions. Unconverted olefins and any alkanes present are then separated from the oligomers by distillation. Example 1 25 g of NiO, 46 ml of trifluoroacetic acid, and 90 ml of distilled water are placed in a 1-pack glass round flask equipped with a magnetic stirring bar and a distillation device. The mixture is refluxed for 2 hours and then the excess NiO is separated off. In this way, nickel trifluoroacetate
An aqueous solution of (CF ₃ COO) ₂ is obtained quantitatively. To this aqueous solution, 135 g of industrial nickel ethyl-2-hexanoate containing 10% free ethyl-2-hexanoic acid and 13% by weight of nickel was added to 500 ml of heptane.
Dissolve and add. This is brought to reflux and the water is then removed by azeotropic distillation. After the water has been completely removed, the heptane is removed by vacuum distillation. In this way, nickel ethyl-2-hexanoate/trifluoroacetate is obtained with a yield of 98%. Elemental analysis: Calculated value as C ₁₀ H ₁₅ O ₄ F ₃ Ni:
C=38.1, H=4.8, Ni=18.7; Actual value: C=
38.4, H=5.4, and Ni=17.8. The infrared absorption spectrum showed the expected characteristic bands. i.e.
They were 1670 cm ^-1 (CF ₃ COO), 1575 and 1410 cm ^-1 (both C ₇ H ₁₅ COO), and 1205 and 1150 cm ^-1 (both CF ₃ ). According to the literature, the infrared absorption spectra of the starting compound Ni trifluoroacetate (CF ₃ COO) ₂ are 1710, 1670, 1430, 1200 and 1145 cm ^-1
shows a characteristic absorption band. In addition, the infrared absorption spectrum of the other starting compound, Ni ethyl-2-hexanoate (C ₇ H ₁₅ COO) ₂ , was determined to be 1690, 1680, 1610,
1585, 1460, 1415, 1315, 1235, 1210, 1150,
It showed characteristic absorption bands at 1115 and 1100 cm ^-1 . As is clear from the comparison of the above absorption bands, the characteristic absorption bands of the compound obtained in this example are the same as those of the starting materials nickel trifluoroacetate and ethyl-2
-It is located at a different position from the characteristic absorption band of nickel hexanoate. Therefore, the compound obtained in this example is not simply a mixture of the above two starting compounds, but is nickel ethyl-2-hexanoate/nickel trifluoroacetate (CF ₃ COO).
It can be seen that it is a mixed salt called (C ₇ H ₁₅ COO) Ni. Also, one of the starting compounds, Ni trifluoroacetate (CF ₃ COO) ₂ , is not soluble in hydrocarbons such as heptane. Therefore, if this starting compound had remained after the reaction, it would have been removed as a heptane-insoluble substance, and the yield of the heptane-soluble compound would have been extremely low. In contrast, in this example, the product was obtained in a high yield of 98%. Therefore, this point also proves the fact that the compound obtained in this example is not a mere mixture of the above two starting compounds, but is the above mixed salt. Examples 2 to 5 The same operation as in Example 1 was performed except that water was replaced with methanol and the halogenoacetic acids shown in the table below were used. As a result, corresponding mixed salts were obtained with the yields shown below. The measured values of the elemental analysis of the product showed no significant difference from the calculated values. In addition, the infrared absorption spectra of the products showed absorption values shown in the table below. The fact that the compounds obtained in these Examples are not mere mixtures of the above two starting compounds but are the above mixed salts is demonstrated as follows. That is, in each example, one of the starting compounds, nickel trifluoroacetate, nickel trichloroacetate, and nickel dichloroacetate, is insoluble in hydrocarbons such as heptane, so these starting compounds remain after the reaction. If so, these are removed as heptane insolubles,
Although the yield of heptane-soluble compounds would have been significantly lower, in each example, each
The product was obtained in a high yield of 95-98%.

[Table] Example 6 (as an example of use) The oligomerization reactor consists of two reaction stages arranged in series, each with an effective volume of 0.25
It is a double-jacketed steel cylindrical reactor whose temperature is controlled by water. Into the reactor constituting the first stage Propane: 1.1 (wt%) Isobutane: 6.7 N-butane: 23.0 Butene-1: 5.2 Trans-butene-2: 46.4 Cis-butene-2: 17.6 C ₄ 98 g/h of distillate and 0.031 g/h of ethyl-2-hexanoic acid/nickel trifluoroacetate in the form of a heptane solution prepared in Example 1.
and 0.194 g/h of dichloroethylaluminum made into a heptane solution were added continuously. The reaction product is continuously removed, the reactor pressure is maintained at 5 bar and the temperature is maintained at 42° C. with water circulation. After 4 hours of operation, stable normal operating conditions are reached, corresponding to a conversion of 66% butene to oligomers at the first stage and 75% at the outlet of the second stage. The oligomer contained 85% dimers (n-octene, methylheptene and dimethylhexene), 12% trimers and 3% tetramers. The activity of this catalyst system is expressed by the rate constant K (mol ^-1・l・h ^-1 ) defined by the relational expression V=KC ² , and is expressed as K (first stage)=0.45mol ^-1・l・h ⁻¹ K (second stage) = equal to 0.11 mol ⁻¹ ·l·h ⁻¹ . However, in the above formula, V is the reaction rate (mol ^-1・
l·h ⁻¹ ), C is the steady-state concentration of butene (mol·l ⁻¹ ) at each stage. Examples 7 to 10 (all as usage examples) Using the nickel compounds of Examples 2 to 5 (in Example 4, the aluminum compound was sesquichloroethylaluminum), the same operation as in Example 6 was carried out. conduct. The activity of the catalyst system was substantially equal to that of Example 6. That is, K (1st stage) = 0.35 ~ 0.45 mol ^-1・l・h ^-1 K (2nd stage) = 0.1 ~ 0.18 mol ^-1・l・h ^-1

Claims (1)

[Claims] 1 General formula (R ₁ COO) (R ₂ COO)Ni [where R ₁
is a hydrocarbon group containing at least 5 carbon atoms, and R ₂ is a halogenoalkyl residue containing 1 to 3 carbon atoms. ₁ COO) ₂ Ni [In the formula, R ₁ has the same meaning as above] A compound represented by the general formula (R ₂ COO) ₂ Ni [In the formula, R ₂ has the same meaning as above]
A method characterized by reacting a compound represented by the formula or a hydrate thereof in a polar solvent, and then recovering the reaction product as a solution in a non-polar solvent and removing the polar solvent. 2. The method of claim 1, wherein the polar solvent is water or an alcohol having 1 to 3 carbon atoms and the non-polar solvent is a hydrocarbon or halogenated hydrocarbon. 3. The method according to claim 1 or 2, wherein the reaction is carried out in the presence of a mixture of a polar solvent and a non-polar solvent. 4. The method according to any one of claims 1 to 3, wherein the non-polar solvent is then evaporated.