JP2000256412A - Preparation of polybutylene - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polybutylene preparation process in which BF3 can be removed and reused through an economical and environmentally non-polluting method by absorbing BF3 selectively on a metal fluoride, which is added to a reaction mixture containing a BF3-based complex catalyst to recover the complexing agent after polymerizing an olefin of 4 carbon atoms. SOLUTION: An olefin of 4 carbon atoms is polymerized in a liquid phase in the presence of a BF3-based complex catalyst consisting of BF3 and a complexing agent. After the polymerization, a metal fluoride shown as MFn (wherein M is Li, Ca, Sr or Ba; and n is 1 or 2) is introduced to the reaction mixture in which at least partially the BF3 complex catalyst is dispersed or dissolved to absorb selectively BF3 in the complex catalyst and recover the complexing agent. Then, by heating the metal tetrafluoroborate shown as M(BF4)n, which is obtained by absorbing BF3, at a temp. of 160-600 deg.C, BF3 and a metal fluoride is obtained. A part of, at least, the recovered BF3 is reused as a catalyst.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a process for producing polybutylene using a boron trifluoride-based complex catalyst comprising boron trifluoride as a polymerization catalyst and a complexing agent, and more particularly to a method for producing C _4. By contacting a polybutylene-containing polymerization product obtained after polymerizing an olefin with a metal fluoride in a gas phase or a liquid phase, expensive and toxic boron trifluoride is removed from the complex catalyst, and the complex A method of recovering the agent, and heating the boron tetrafluoride metal salt obtained by adsorption of boron trifluoride to separate it into metal fluorides and boron trifluoride gas, and recovering the respective trifluoride. The present invention relates to a method of re-preparing a boron trifluoride-based complex catalyst from boron fluoride and a complexing agent, and reusing the catalyst.

[0002]

2. Description of the Related Art A polymer having a vinylidene structure as a double bond structure in polybutylene is useful because a reaction with maleic acid or the like proceeds at a high rate. For this reason, several techniques have been proposed to make polybutylene contain more vinylidene structure. For example, US Pat. No. 4,152,
No. 499 discloses that a gaseous boron trifluoride or a boron trifluoride-based complex catalyst which forms a complex with water or alcohols as a polymerization catalyst is used.
Isobutene is polymerized in a temperature range of
A polymerization technique for obtaining a polyisobutene of 00 is disclosed in which a vinylidene double bond is added at the terminal position.
It is said that it can be contained in an amount of 0 to 90%. EP-A-145,235 also discloses boron trifluoride preformed as a polymerization catalyst and C ₁ -C _8.
Polymerization is carried out using a complex catalyst with an alcohol, and 70 to 90% of a vinylidene double bond is located at a terminal position in polyisobutene.
It is disclosed that it could be included.

As described above, boron trifluoride-based complex catalysts are often used in the production of polybutylene such as polyisobutene, and these complex catalysts have a specific complexing agent selected. The number of coordination moles as a complexing agent is also limited to a specific value.

On the other hand, after the completion of the polymerization reaction of polybutylene, it is necessary to separate and remove boron trifluoride in the complex from the reaction mixture. For this reason, conventionally, a method of industrially adopting a method of neutralizing with an aqueous solution of a basic substance such as ammonia, caustic soda, lime or the like, followed by washing with water. However, in such a method, it is impossible to reuse the catalyst, and since the neutralization and washing steps discharge wastewater containing fluoride used as a neutralized product of alkali and boron trifluoride, In recent years, it has been desired to take measures to eliminate the environmental pollution in consideration of the problem. Furthermore, since boron trifluoride itself is expensive, it is economically and environmentally beneficial to recover and reuse it, and various recovery methods have been proposed.

For example, there has been proposed a method of heating and separating a boron trifluoride-based complex catalyst from a reaction mixture.
U.S. Pat. No. 4,263,467 to dgavkar et al. discloses a process for removing boron trifluoride as a gas by slowly moving the reaction product over an inert metal or ceramic bed. Japanese Patent Application Laid-Open No. 6-287221 discloses that in a system using a boron trifluoride-based complex catalyst, a boron trifluoride gas is generated by heating a reaction mixture, and an excess amount of a complexing agent with respect to the generated gas. Are contacted to form a new complex, which is recycled to the reaction tank and reused. Further, JP-A-8-3
No. 33472 discloses boron trifluoride and C ₁ -C
When producing an α-olefin oligomer using a boron trifluoride-based complex catalyst composed of a reaction accelerator of ₈ alkanols, boron trifluoride gas is produced by thermally decomposing the complex from the product fluid. A method is disclosed for obtaining and recycling a low temperature α-olefin oligomer stream containing an accelerator.

However, in these methods, boron trifluoride having high reaction activity or a complex thereof is heated in the presence of the reaction mixture, which may adversely affect the composition of the reaction mixture. In particular, polybutylene containing a large amount of the above-mentioned vinylidene olefin structure causes isomerization of the olefin by heating in the presence of the complex, and as a result, the quality of the product is reduced.

As another means for recovering a boron trifluoride complex catalyst, Vogel et al., US Pat. Nos. 4,454,366 and 4,384,162 disclose boron trifluoride in an oligomerization reaction. A method using polyvinyl alcohol for removal is disclosed. In Vogel et al., U.S. Pat. No. 4,433,197, the reaction product is contacted with silica to remove boron trifluoride. Mo
U.S. Pat. No. 4,429,177 to rgenson et al.
U.S. Pat. Nos. 4,213,001 and 4,30 to dgavkar et al.
No. 8,414 also uses silica as an absorber for boron trifluoride in the oligomerization reaction. Madg
U.S. Pat. No. 4,394,296 to Avkar et al. discloses the use of hydrated silica as a co-catalyst with boron trifluoride in an oligomerization process, followed by filtration and reuse of the hydrated silica.

[0008] However, the above method is not always a satisfactory technique when not only adsorbing boron trifluoride but also recovering and reusing boron trifluoride. That is, when the former polyvinyl alcohol is used, the thermal stability of the polyvinyl alcohol itself is poor, and it is difficult to use the polyvinyl alcohol repeatedly.
The same applies to the method disclosed in U.S. Pat. No. 2,997,371 in which acrylonitrile is polymerized on activated carbon and boron trifluoride in gas is separated and removed by polyacrylonitrile supported on activated carbon. That is, in addition to the insufficient ability to adsorb and remove boron trifluoride, the desorption temperature of boron trifluoride is equal to or higher than the melting point of polyacrylonitrile, and cannot be used repeatedly as an adsorbent after desorption. In the case of hydrous silica as the latter co-catalyst, the functional groups such as siloxane and silanol groups present in the silica molecules decompose boron trifluoride during the separation of boron trifluoride, and as a result can be reused It has been found that it is difficult to recover boron trifluoride in a proper state.

[0009] Another method for removing boron trifluoride is described in US Pat. No. 4,981,578 to Tycer et al. By contacting an oligomer product stream with a solid or aqueous solution of KF, NaF or NH ₄ F. A method for removing boron fluoride is disclosed. U.S. Pat. No. 4,956,513 to Walker et al. Discloses a method for removing boron trifluoride from an oligomer reaction product by extracting it with water.

[0010] All of the above methods are only intended to remove boron trifluoride from a product stream containing a boron trifluoride-based complex catalyst, from which boron trifluoride can be re-used. It is not intended to be recovered. Further, in the former method, even if boron trifluoride is removed using KF, NaF or NH ₄ F, boron tetrafluoride sodium salt (NaB
F ₄ ) and the potassium salt (KBF ₄ ) have a thermal decomposition temperature of
The temperatures are 650 ° C. or higher and 750 ° C. or higher, respectively, and are not practical in industrial production in consideration of the energy cost required for thermal decomposition when recovering boron trifluoride. Further, NH ₄ F itself is very weak to heat and decomposes into NH ₃ and HF, which is not practical.

From the above disclosure of the production process using a boron trifluoride-based complex catalyst in the prior art, many methods for extracting boron trifluoride have been proposed, and great efforts have been made for development. Understood. However, at present, in a production process using a boron trifluoride-based complex catalyst, particularly in a method for producing polybutylene, a method for recovering reusable boron trifluoride by a method that does not cause environmental pollution and economically. Has not been proposed.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing an expensive boron trifluoride from a reaction mixture containing a boron trifluoride-based complex catalyst in an economical manner and without causing environmental pollution. It is an object of the present invention to provide a method for producing polybutylene, which comprises removing the boron trifluoride efficiently, removing the boron trifluoride, and reusing the complex.

[0013]

Means for Solving the Problems The present inventors removed boron trifluoride from a polybutylene reaction mixture containing a boron trifluoride-based complex catalyst as described below,
Furthermore, the inventors have found an epoch-making method for producing polybutylene, in which the recovered boron trifluoride is complexed and reused, and completed the present invention. That is, the first of the present invention is the following (I)
And (III). (I) a step of liquid-phase polymerization of a C ₄ olefin in the presence of a boron trifluoride-based complex catalyst comprising boron trifluoride and a complexing agent; (II) a boron trifluoride-based complex after polymerization of the C ₄ olefin A metal fluoride represented by the following formula (1) is brought into contact with a reaction mixture obtained by dispersing and / or dissolving at least a part of the catalyst to selectively adsorb boron trifluoride (BF ₃ ) in the complex catalyst. MF _n Step of Formula (1) (M represents a metal atom of lithium, calcium, strontium or barium; n = 1 or 2) ( III) A step of recovering a reaction mixture containing a complexing agent from which boron trifluoride has been adsorbed and removed.

The second aspect of the present invention relates to a method for producing polybutylene including the following steps (I) to (V). (I) a step of liquid-phase polymerization of a C ₄ olefin in the presence of a boron trifluoride-based complex catalyst comprising boron trifluoride and a complexing agent; (II) a boron trifluoride-based complex after polymerization of the C ₄ olefin A metal fluoride represented by the following formula (1) is brought into contact with a reaction mixture obtained by dispersing and / or dissolving at least a part of the catalyst to selectively adsorb boron trifluoride (BF ₃ ) in the complex catalyst. MF _n Step of Formula (1) (M represents a metal atom of lithium, calcium, strontium or barium; n = 1 or 2) ( III) a step of collecting a reaction mixture containing a complexing agent from which boron trifluoride has been adsorbed and removed, and (IV) a tetrafluoride represented by the following formula (2) obtained by adsorbing boron trifluoride to metal fluoride. Boron metal salt, in the temperature range of 160-600 ° C Obtaining a boron trifluoride and the metal fluoride by heating, M (BF _{4) n} ·············· formula (2) (M is lithium, calcium, strontium Alternatively or .n = 1 indicates a metal atom of barium 2) (V) at least part of the recovered boron trifluoride as a catalyst, the step of liquid phase polymerization of C ₄ olefin.

A third aspect of the present invention relates to a method for producing polybutylene including the following steps (I) to (VI). (I) a step of liquid-phase polymerization of a C ₄ olefin in the presence of a boron trifluoride-based complex catalyst comprising boron trifluoride and a complexing agent; (II) a boron trifluoride-based complex after polymerization of the C ₄ olefin A metal fluoride represented by the following formula (1) is brought into contact with a reaction mixture obtained by dispersing and / or dissolving at least a part of the catalyst to selectively adsorb boron trifluoride (BF ₃ ) in the complex catalyst. MF _n Step of Formula (1) (M represents a metal atom of lithium, calcium, strontium or barium; n = 1 or 2) ( III) a step of collecting a reaction mixture containing a complexing agent from which boron trifluoride has been adsorbed and removed, and (IV) a tetrafluoride represented by the following formula (2) obtained by adsorbing boron trifluoride to metal fluoride. Boron metal salt in a temperature range of 160 to 600 ° C A step of obtaining boron trifluoride and metal fluoride by heating, M (BF ₄ ) _n (2) (M is lithium, calcium, strontium (V) a step of recovering the complexing agent liberated in the reaction mixture when the boron trifluoride in the complex catalyst is adsorbed in the step (II); VI) using at least a part of each of the boron trifluoride recovered from the step (IV) and the complexing agent recovered from the step (V) to newly form a boron trifluoride-based complex catalyst; a step of liquid phase polymerization of C ₄ olefin as a polymerization catalyst.

A fourth aspect of the present invention is the method according to any one of the first to third aspects of the present invention, wherein C _{4 in the} feedstock in the liquid phase polymerization is used.
It relates to a method for producing polybutylene having an olefin concentration of at least 5% by weight. In a fifth aspect of the present invention, in any one of the first to third aspects of the present invention, the temperature of the reaction mixture brought into contact with the metal fluoride is in the range of -100 ° C to + 160 ° C, preferably -30 ° C to + 50 ° C. And a method for producing polybutylene. Sixth Embodiment
Is a metal salt of boron tetrafluoride (M (BF) formed by adsorption of boron trifluoride in the second or third aspect of the present invention.
₄ ) _n ) at 100-600 ° C, preferably 160-5
The present invention relates to a method for producing polybutylene, which is decomposed into boron trifluoride and metal fluoride by heating in a temperature range of 00 ° C. According to a seventh aspect of the present invention, in any one of the first to third aspects of the present invention, the complexing agent for forming the boron trifluoride-based complex catalyst is water, alcohols, ethers, phenols, ketones, aldehydes. , Esters, organic acids, oxygen-containing compounds such as acid anhydrides, nitrogen-containing compounds, sulfur-containing compounds, phosphorus-containing compounds or inorganic acids,
The present invention relates to a method for producing polybutylene, which is selected from the group consisting of organic or inorganic polar compounds. An eighth aspect of the present invention is the composition according to any one of the first to third aspects, wherein the molar ratio of boron trifluoride to the complexing agent in the boron trifluoride-based complex catalyst is 0.01: 1 to 2: 1. A process for producing polybutylene, characterized by being within the range. A ninth aspect of the present invention relates to the method for producing polybutylene according to any one of the first to third aspects of the present invention, wherein the molecular weight of polybutylene is in the range of 100,000 to 100,000.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The amount of boron trifluoride used in the cationic polymerization of olefins is usually 0.0001 to 0.5 mol per 1 mol of the polymerizable olefin component. After the completion of the reaction, the boron trifluoride-based complex catalyst is stably present in the reaction mixture in a form in which at least a part thereof is dissolved and / or dispersed. It is very difficult to recover the dissolved and / or dispersed complex catalyst, and the boron trifluoride-based complex catalyst cannot be separated and reused from the reaction mixture as it is. The present invention further comprises recovering boron trifluoride and the complexing agent separately from the dissolved and / or dispersed complex catalyst present in the reaction mixture,
This is a technique for greatly reducing the cost of the catalyst and the load of the subsequent post-treatment step by reusing it as a boron trifluoride-based complex catalyst.

According to the present invention, a metal fluoride represented by the following formula (1) is added to a reaction mixture in which at least a part of a boron trifluoride complex catalyst used as a catalyst in the production of polybutylene is dissolved and / or dispersed. By contacting, expensive and toxic boron trifluoride is removed by an economical and environmentally clean method and with high efficiency using chemisorption. An object of the present invention is to provide a method for producing polybutylene, which reuses boron trifluoride recovered by heating a boron fluoride metal salt. MF _n ... Equation (1) M (BF ₄ ) _n Equation (2) ( M represents a metal atom of lithium, calcium, strontium or barium, where n = 1 or 2)

[0019] Boron trifluoride-based complex catalysts, mainly butadiene, isobutene, butene-1, cis - or trans - used in the polymerization of _{C 4} olefins such as butene-2. C ₄ olefins include C ₂ -C 4 such as ethylene, propylene, isoprene, pentene, and hexene-1.
₂₀ aliphatic olefin, styrene, aromatic olefins C ₈ -C _10, such as vinyl toluene, can be subjected to alicyclic olefins such be mixed polymerization such as DCPD.

In the polymerization, the concentration of the olefin present in the feed is preferably in the range of 5 to 100% by weight. If the olefin concentration is less than 5% by weight, the loss is practically and economically large, which is not preferable. In addition to the olefin, a solvent inert to the reaction, for example, a hydrocarbon such as n-paraffin such as n-butane and an isoparaffin such as isobutane and isooctane can be appropriately used. The industrial raw material, C ₅ fraction containing aliphatic olefins such as piperylene, or with isobutene 1-butene, trans - comprises or olefins cis -2-butene and the like, including further isobutane, also n- butane C ₄
A fraction or the like can be used.

The complexing agent used in the present invention forms a complex with boron trifluoride by physical or chemical bonding. Specific examples of such complexing agents include alcohols, ethers, phenols, ketones, aldehydes, esters, organic acids, oxygen-containing compounds such as acid anhydrides, nitrogen-containing compounds, sulfur-containing compounds, Organic or inorganic polar compounds such as phosphorus-containing compounds or inorganic acids are exemplified.

More specifically, alcohols include:
An aromatic or C _{1 to} C ₂₀ aliphatic alcohol is used, and the C _{1 to} C ₂₀ carbon skeleton may be a linear alkyl group or a branched alkyl group, and may be an n-, sec-, tert-alkyl group or An alicyclic alkyl group or an alkyl group containing an alicyclic ring may be used. Specifically, methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol,
Nonanol, decanol or benzyl alcohol,
Examples include, but are not limited to, cyclohexanol. Further, polyhydric alcohols such as diol and triol may be used.

As the ethers, aromatic or C ₁
Ether is used having an aliphatic hydrocarbon group -C _20, carbon skeleton of the C ₁ -C ₂₀ may be either branched alkyl group with a straight chain alkyl group, n-, sec-, tert-alkyl group, or An alicyclic alkyl group or an alkyl group containing an alicyclic ring may be used. Specifically, dimethyl ether, diethyl ether, methyl ethyl ether, dipropyl ether, methyl propyl ether, ethyl propyl ether, dibutyl ether, methyl butyl ether, ethyl butyl ether, propyl butyl ether, dipentyl ether, or phenyl methyl ether, phenyl ethyl ether, Examples thereof include diphenyl ether, cyclohexylmethyl ether, and cyclohexylethyl ether.

As the phenol, 1-3 phenol is suitable, and specifically, phenol, cresol and the like are preferable.

The ketones include aromatic or C ₁ -C
Ketones having ₆ hydrocarbon group is used, the C ₁ ~
The carbon skeleton of C ₆ may be a linear alkyl group or a branched alkyl group, and may be an n-, sec-, tert-alkyl group, an alicyclic alkyl group, or an alkyl group containing an alicyclic ring. Specific examples include methyl ethyl ketone, diethyl ketone, methyl butyl ketone, and cyclohexanone.

As the esters, aromatic or C ₁
Fatty alcohol component of the -C _6, an aromatic or C
Those in which an ester bond is formed by an aliphatic carboxylic acid or phosphoric acid component of _{1 to} C ₆ are used, and the C _{1 to} C 6
The carbon skeleton of ₆ may be a linear alkyl group or a branched alkyl group, and may be an n-, sec-, tert-alkyl group, an alicyclic alkyl group, or an alkyl group containing an alicyclic ring. Specifically, complete esters of phosphoric acid such as methyl formate, ethyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, pentyl acetate, hexyl acetate, ethyl hexanoate, ethyl benzoate and the like, and tributyl phosphate and the like Is mentioned.

As the organic acids, aromatic or C _1-
C ₆ aliphatic carboxylic acids, their halogen-substituted products,
Phosphoric acid or a partial ester of phosphoric acid and an aromatic or C _{1 to} C ₆ aliphatic alcohol component is used, and the C _{1 to} C ₆ carbon skeleton may be a linear alkyl group or a branched alkyl group. , An n-, sec-, tert-alkyl group or an alicyclic alkyl group, or an alkyl group containing an alicyclic ring. Specific examples include formic acid, acetic acid, propionic acid, oxalic acid, malonic acid, benzoic acid, diethyl phosphate and the like. Phosphoric acid, hydrochloric acid, and the like are used as the inorganic acids.

One of these complexing agents may be used alone in each complex system, or two or more complexing agents may be mixed and used at an appropriate ratio. The complex itself can be produced according to a conventionally known method. For example,
A complex may be prepared and used in advance, or boron trifluoride and one or more complexing agents may be separately or simultaneously charged into the reaction system at a predetermined ratio, and the boron trifluoride complex may be added in the reactor. Can also be formed. In the present invention, any of the methods can be adopted.

The molar ratio of boron trifluoride to the complexing agent is
It is preferably in the range from 0.01: 1 to 2: 1.
If the molar ratio of boron trifluoride to the complexing agent is less than 0.01, the catalytic activity is too low to carry out the intended polymerization of the olefin. On the other hand, if the molar ratio of boron trifluoride to the complexing agent exceeds 2, the boron trifluoride becomes excessive compared to the complexing agent, making it difficult to maintain stable coordination. The molar ratio between boron trifluoride and complexing agent cannot be maintained. When the recovered boron trifluoride-based complex catalyst is reused as described later, an operation such as the above-described molar ratio adjustment is required, and therefore, control is performed so that the coordination molar ratio does not change during the recovery. This is very important.

The polymerization of the C ₄ olefin in the step (I) is a liquid phase polymerization, and the temperature is from -100 ° C. to + 50 ° C.
Preferably, it is in the range of -40 ° C to + 10 ° C. At low temperatures below this range the conversion of C ₄ olefin component is suppressed. On the other hand, if the temperature is higher than this, the conversion is suppressed and side reactions such as isomerization and rearrangement occur, which makes it difficult to obtain polybutylene. As a reaction system, any of a continuous system and a batch system can be adopted. From the point of industrial production, the continuous method is more economical and efficient. In the case of a continuous system, the contact time between the feed and the catalyst is important, and it is desirable that the contact time be in the range of 5 minutes to 4 hours. If the contact time is less than 5 minutes, a sufficient conversion of C ₄ olefin is not obtained, while if it exceeds 4 hours, economical loss is large, and isomerization of the produced butylene polymer by prolonged contact with the catalyst. All of these are not preferred because they promote side reactions such as reaction and rearrangement. In order to improve the commercial profit in the production of butylene polymer, C ₄ fractions, for example, C ₄ C ₄ olefin conversion in the raffinate that higher is desirable, adopted polymerization conditions of the present invention The conversion of isobutene is 80-1.
It is possible to achieve 00%. After the polymerization, the reaction solution containing the unreacted components, the produced butylene polymer, and the catalyst flows out. A boron trifluoride-based complex catalyst is dissolved or dispersed in the reaction mixture as the reaction solution.

In order to adsorb and remove boron trifluoride from the reaction mixture in which at least a part of the above-mentioned boron trifluoride complex catalyst is dissolved and / or dispersed, the reaction mixture and the metal fluoride are mixed with each other at −100. The contact is made in the range of not lower than + 160 ° C. Within this temperature range, the chemical adsorption efficiency of boron trifluoride is high, and any temperature of 160 ° C. or lower can be adopted as long as the mixture comes into contact with the gas phase and / or liquid phase.

When a boron trifluoride complex catalyst having high reaction activity is heated in the presence of a reaction mixture, as described above, isomerization occurs in the vinylidene structure in polybutylene, which causes deterioration in product quality. Therefore, a more preferable adsorption temperature is + 50 ° C. or less, and preferably in a range of −30 ° C. to + 50 ° C. in consideration of a change in the composition and chemical structure of the product.

As described above, when a metal fluoride (MF _n ) is brought into contact with a reaction mixture in which at least a part of a boron trifluoride-based complex catalyst is dissolved and / or dispersed, the following formula (3) or (3) The reaction shown in 4) proceeds easily, and the metal fluoride becomes a boron tetrafluoride metal salt (M (BF ₄ ) _n ) that is hardly soluble in the target reaction mixture. further,
At that time, the complexing agent in the catalyst is released into the reaction mixture in a free form, so that only the target boron trifluoride can be trapped and removed from the reaction mixture. nBF ₃ + MF _n → M (BF ₄ ) _n ... formula (3) nBF _3- (complexing agent) + MF _n → M (BF ₄ ) _n + n (complexing agent) Formula (4) (M in the formula (3) or (4) represents a metal atom of lithium, calcium, strontium or barium, and In the case, n = 1, and in the case of other metals, n = 2.)

Here, metal fluorides (MF _n ) used for the adsorption of boron trifluoride are chemical substances used in large quantities in various industries such as steel, nickel refining, glass, enamel, and cement. However, in the present invention,
Any of natural products, synthetic products, and products obtained from industrial wastes may be used. Hereinafter, calcium fluoride (CaF ₂ ) used as the metal fluoride will be described in detail.

The natural product of calcium fluoride is widely known as fluorite, and is widely used in Mexico, Russia, France,
It is a common ore produced in large quantities from countries around the world, such as Spain, China, Thailand, the United States, Italy, and South Africa. Preferably, it is desirable to select a colorless high-quality ore containing 98% or more of calcium fluoride.

Further, hydrogen fluoride (HF) and slaked lime (C
It is known that calcium fluoride is synthesized from a (OH) ₂ ) or calcium chloride (CaCl ₂ ) according to the reaction shown in the following formula (5) or (6). Can be used. Calcium fluoride synthesized by these reactions may be used as it is, separated by an operation such as spontaneous sedimentation or filtration. It is more preferable to use a material which has been washed and dried by heating. 2HF + Ca (OH) ₂ → CaF ₂ + 2H ₂ O (5) 2HF + CaCl ₂ → CaF ₂ + 2HCl ( ₂ ) ... Equation (6)

Further, in an example where hydrogen fluoride (HF) or the like is used as a catalyst for the production of alkylbenzene or the like,
In order to deactivate the catalyst after the completion of the reaction, hydrogen fluoride is usually neutralized as shown in the above formula (5) or (6). At that time, calcium fluoride is produced as an industrial waste by-product. I do. Even if the by-product calcium fluoride is used in the present invention, there is no problem.

When the boron trifluoride contained in the reaction mixture is a complex as described above, the concentration as boron trifluoride may be considerably high. However, in order to increase the removal efficiency by adsorption, it is usually preferable to use a dilute liquid of boron trifluoride. In particular,
The content of boron trifluoride is 10% by weight or less, more preferably 5% by weight or less. The lower the concentration, the higher the removal efficiency, and the lower limit of the concentration is not particularly limited.

The polybutylene in the present invention is obtained by liquid phase polymerization of an olefin, and the number average molecular weight of the obtained polybutylene is preferably in the range of 100,000 to 100,000. The removal effect of boron trifluoride in the boron trifluoride-based complex catalyst is also greatly dependent on the viscosity of the reaction solution, and when polybutylene with a small degree of polymerization is produced, when a product with a large degree of polymerization is produced Since the viscosity of the reaction solution is smaller than that of the above, the dispersion efficiency of the metal fluorides is improved.
However, if the molecular weight is less than 100, the molecular weight is too small to be useful as polybutylene. When the viscosity of the reaction mixture is extremely high, dispersion of metal fluorides and adsorption and removal of boron trifluoride in the complex catalyst become insufficient. From such a viewpoint, the viscosity of the reaction mixture of interest is 10,000 at the temperature at the time of contact with metal fluorides.
It is preferably 0 cP (centipoise) or less.

Further, by adding an inert solvent to the reaction mixture, it is possible to adjust the viscosity of the system within the above range and to remove boron trifluoride in the complex catalyst. However, when the molecular weight exceeds 100,000, the amount of the diluting solvent required for separating the reaction solution and the adsorbent becomes too large, which is not economical.

On the other hand, the crystal structure of boron tetrafluoride metal salt (M (BF ₄ ) _n ) formed by adsorption of boron trifluoride in a boron trifluoride complex catalyst on metal fluoride (MF _n ) For example, Acta Crystallo by Jordan, TH et al.
According to the papers of gr., Sect. B (1975), B 31 (3), p. 669-672, they are known to be colorless orthorhombic crystals. That is, both calcium fluoride and calcium boron tetrafluoride are very stable substances as inorganic crystals.

The method of contacting the reaction mixture in which at least a part of the boron trifluoride-based complex catalyst is dissolved and / or dispersed with the metal fluoride is not particularly limited. For example, a fluid containing boron trifluoride or a complex can be passed through a fixed bed filled with metal fluoride alone or mixed with an inert inorganic filler or the like. Examples of the inert inorganic filler to be filled together with the metal fluoride include activated carbon and stainless steel packing, but the material or shape is not limited to these. The metal fluoride does not need to be completely calcined, but it is desirable to remove water as much as possible in the production of polybutylene. Is preferred.

The particle size of the metal fluoride used is not particularly limited. For example, when the particle size distribution of the metal fluoride of a commercial reagent is examined in detail, it is in the form of fine particles in the range of 1 to 10 μm, but it may be molded to have a uniform particle size distribution. In order to further increase the adsorption efficiency of boron trifluoride, it is preferable to increase the surface area of metal fluoride as an adsorbent.

The shape of the metal fluoride to be used is not particularly limited. For example, the cross-sectional shape of the metal fluoride may be an ordinary circular shape, a hollow shape, or a special porous shape. It can be used and is preferably selected appropriately according to the purpose.

The contact operation can be carried out in any of a flow system and a batch system. The contact time is not particularly limited, either, and is appropriately determined. Usually, in the flow type, the space velocity can be selected from the range of 0.01 to 10 hr ^-1 . The amount of the metal fluoride used to completely remove the boron trifluoride in a batch system is at least 0.5 times the molar amount of the boron trifluoride contained in the target reaction mixture. (0 times or more), and it is preferable to use a larger amount of the metal fluoride in order to increase the removal efficiency, but the amount used can be appropriately selected.

According to the above method, boron trifluoride in the boron trifluoride-based complex catalyst is chemically adsorbed by contact with the metal fluoride and separated and removed from the reaction mixture. After removing the boron trifluoride by such an adsorption treatment, the target polybutylene can be obtained from the reaction mixture by an appropriate separation means, for example, a distillation operation. If necessary, the complex catalyst contained in the produced polybutylene can be removed by a conventionally known method, for example, an appropriate neutralization step. Such removal of the complex catalyst in polybutylene can be easily performed because most of the complex catalyst has already been removed.

Next, in order to desorb the adsorbed boron trifluoride from the metal fluoride and recover it in a reusable state,
Boron tetrafluoride metal salt generated by adsorption (M (BF ₄ )
_n ) heating is performed. That is, the reaction represented by the following formula (7) proceeds, and it is possible to return to the form of pure boron trifluoride gas and the original metal fluoride as the adsorbing substance. M (BF ₄ ) _n → nBF ₃ + MF _n Equation (7) (M in Equation (7) is lithium, Represents a metal atom of calcium, strontium or barium, n = 1 for a lithium atom, and n = for other metals
2. )

The heating is performed by using an appropriate inert gas such as nitrogen.
Which can be done in the presence. Be inert
For example, heating in an appropriate organic solvent is also possible. three
The desorption temperature of the boron fluoride gas is 100 ° C. or higher,
Temperature range of 160 ° C or higher for sufficiently high deposition speed
It is desirable that However, as shown below,
Desorption of boron trifluoride by metal fluoride
The temperature required for desorption is different, so the desorption temperature should be selected appropriately.
Is desirable.Required desorption temperature for each metal  Lithium: 160 ° C or higher Calcium: 210 ° C or higher Strontium: 260 ° C or higher Barium: 240 ° C or higher

The upper limit of the temperature required for desorption is not particularly limited because all of the metal fluorides used in the present invention are stable crystals that do not melt until about 1,000 ° C. This is preferable because desorption proceeds quickly. However, a remarkably high temperature exceeding 600 ° C. is not essentially required, and is not preferable because it causes problems such as an increase in energy cost, decomposition of an organic solvent, and corrosion of the device by boron trifluoride gas at a high temperature. Desorption of boron trifluoride can be completely achieved by maintaining the above heating temperature conditions, but when metal fluoride as an adsorbent is used repeatedly, the desorption rate of boron trifluoride is adjusted to an appropriate stage. Fastening is preferable from an economical point of view.

Further, the metal fluoride to which the boron trifluoride has been adsorbed and desorbed by the method of the present invention can be used repeatedly. The boron trifluoride recovered by the method of the present invention is usually in a gaseous state and has high purity. Thus, the desorbed boron trifluoride is recovered by an appropriate means, which can be reused as a catalyst for polymerization of C ₄ olefin.

Further, simultaneously with the separation and recovery by desorption of boron trifluoride, the complexing agent in the boron trifluoride-based complex catalyst can be recovered in its entirety from the reaction mixture. That is, when boron trifluoride is adsorbed and removed from the boron trifluoride-based complex catalyst, the complex is decomposed and the boron trifluoride is captured by the metal fluoride, and at the same time, the complexing agent is added to the reaction mixture. To be liberated. The complexing agent released here can be recovered by distillation or the like. Therefore, in order to reduce the production cost, the complexing agent released from the reaction mixture is recovered, and the recovered complexing agent and boron trifluoride recovered from a separate step are used to recover the trifluoride again. It is also possible to prepare a boron halide complex catalyst. It is not always necessary to collect the entire amount of the complexing agent, and the necessary amount of fresh complexing agent may be appropriately replenished.

Furthermore, when reusing as a catalyst for producing polybutylene, care must be taken not to change the coordination number of the complexing agent in the complex catalyst. The complexing agent that coordinates to the complex exhibits a desired catalytic function by specifying the coordination number, but the coordination number of the complexing agent is liable to change depending on temperature and other environmental conditions. . If the coordination number changes, the catalytic function will differ,
It is necessary to prepare the complex again using the boron trifluoride and the complexing agent recovered in different steps so that the coordination number exhibits the desired catalytic performance. Through the above operation, the boron trifluoride-based complex catalyst whose coordination number is specified can be reused in the polybutylene polymerization step.

[0053]

The present invention will be further described with reference to the following examples.
You. Boron trifluoride gas desorbed by the method of the present invention
Is determined in accordance with a conventionally known analysis method described below.
Boron trifluoride or its complex is converted to an aqueous solution of calcium chloride
Is reacted with 1 according to the reaction shown in the following formula (8).
3 moles of hydrochloric acid and 1 mole of boron from moles of boron trifluoride
Acid is generated, and the generated hydrochloric acid is converted to sodium hydroxide or
Neutralized with aqueous alkali solution of known normality such as potassium hydroxide
By titration, it is possible to know the concentration of existing fluorine
it can. Further, boric acid produced according to the formula (8) is
Japanese Industrial Standards (JIS) K8861-199
Determined according to the acid content test method
The concentration of boron to be obtained. That is, Ho
Of acid and mannitol to form a water-soluble strongly acidic complex
Is a method that utilizes the quality of
Hoe by neutralization titration with a known alkaline aqueous solution
The acid content can be known, and the value
Find the concentration of 2BF₃+ 3CaCl₂+ 6H₂O → 2H₃BO₃+ 6HCl + 3CaF₂  ・ ・ ・ ・ ・ ・ ・ ・ ・ Equation (8)

The actual method used for specifying boron trifluoride in the present invention is as follows. First, boron trifluoride in a reaction mixture containing a boron trifluoride-based complex catalyst is adsorbed on a metal fluoride to form a boron tetrafluoride metal salt (M
(BF ₄ ) _n ) and then heating the adsorbed salt to form
The released boron trifluoride is absorbed in a solution such as water, lower alcohol or diethyl ether. Next, the absorbing solution was reacted with an aqueous solution of calcium chloride,
The neutralization titration of the stage is performed, and the contents of fluorine and boron are examined to obtain the respective atomic composition ratios and the boron trifluoride concentration. The free gas obtained in the present invention had an atomic molar ratio of fluorine to boron of 3: 1 in any case, and it was confirmed that the form of boron trifluoride (BF ₃ ) was maintained.

<Production of boron trifluoride-based complex catalyst>
The complexing agent held below was mixed with boron trifluoride (purity 99.
7%) to prepare a complex catalyst. Although not specifically shown, the complex which is likely to decompose was prepared and stored at a decomposition temperature or lower and used for the reaction.

<Specifications of Experimental Apparatus> As the polymerization apparatus, a 1-liter pressure-resistant vessel equipped with a nitrogen gas introduction pipe, a stirrer, a cylinder for storing boron trifluoride gas, a gas injection pipe, a thermometer and a low-temperature cooling tank was used. It was used. Commercially available reagents were used for all the metal fluorides to be added.

<Example 1> (Polymerization reaction of polyisobutylene) In a nitrogen stream, 100 g of a special grade reagent, isooctane, was used as a diluting solvent in the flask.
g of pure isobutene was supplied while stirring and keeping the temperature of the flask at -25 ° C., and boron trifluoride diethyl ether complex (1: 1 mol adduct) was added therein.
Then, the polymerization reaction was carried out with vigorous stirring for 30 minutes.

(Adsorption Removal of Boron Trifluoride) After the polymerization was completed, calcium fluoride (purity 98%) was added to the reaction mixture in which boron trifluoride diethyl etherate was dispersed at a constant temperature of 25 ° C. while stirring. %) 4.59g
(Equivalent to 4 times the molar amount of boron trifluoride) and 30
Stirring was performed for minutes. When the dispersion is allowed to stand and the stirring is stopped, the adsorbent and the reaction mixture are separated into two phases due to a difference in specific gravity.
The concentration of boron trifluoride remaining in the reaction mixture was measured by the analytical method described for. The concentration of the remaining boron trifluoride was zero, and it was confirmed that the boron trifluoride was completely absorbed and removed. Further, when gas chromatography analysis was performed on the reaction mixture,
The total amount of diethyl ether corresponding to the input amount of the boron trifluoride diethyl etherate complex was detected. Isooctane and light components were distilled off from the reaction mixture by distillation under reduced pressure, and the conversion of isobutene involved in the polymerization reaction and the yield of polyisobutene produced were determined. Next, the adsorbent was separated by filtration and dried under reduced pressure to confirm a change in weight.
As a result of calculating the difference from the weight before adsorption to calcium fluoride, it was found that the amount of boron trifluoride adsorbed and held in the added calcium fluoride was 21.7 g / 100 g-calcium fluoride. . Further, when an X-ray diffraction analysis was performed on the dried calcium fluoride adsorbent onto which the dried boron trifluoride was adsorbed and held, it was found that calcium fluoride (CaF ₂ )
And boron tetrafluoride calcium salt (Ca (BF ₄ ) ₂ )
The two types of crystal structures were confirmed.

(Heat Desorption) A calcium fluoride adsorbent on which boron trifluoride is adsorbed and held is filled in a stainless steel tubular container, and nitrogen is supplied at a flow rate of 1 ml / min (standard state). Heating was started and the temperature was maintained at 270 ° C. The nitrogen flowing out of the outlet was introduced into the diethyl ether solution recovered by distillation after the adsorption of boron trifluoride. In this state, nitrogen from the outlet was observed, and the introduction of heated nitrogen was continued until no white smoke due to boron trifluoride was observed. Thereafter, the powder was cooled and the weight of the remaining powder was weighed. As a result, the remaining amount of boron trifluoride was zero, and it was confirmed that 100% of the adsorbed boron trifluoride was desorbed. Further, when the remaining powder was subjected to X-ray diffraction analysis in the same manner as at the time of adsorption, only the crystal structure of calcium fluoride (CaF ₂ ) was observed, and it was confirmed that the powder had recovered to the original form. The two-stage neutralization titration was performed on the diethyl ether solution having absorbed the desorbed gas by heating, and the contents of fluorine and boron were examined.
Calculate the atomic molar ratio of fluorine and boron from the obtained value,
At the same time, the amount of the remaining boron trifluoride was determined. As a result, the form of boron trifluoride (BF ₃ ) in which the atomic molar ratio of fluorine to boron was 3: 1 was confirmed. .05 g was found to be reconstituted. As a result, it was confirmed that the boron trifluoride diethyl ether complex catalyst charged during the polymerization can be recovered at a high rate of 98% or more in the form of a reusable complex even after the adsorption and desorption treatment.

Further, the boron trifluoride-diethyl ether complex catalyst was analyzed by ¹³ C-NMR. Figure 1 is a definitive after previous, and recovered after use to be used in the reaction of boron trifluoride-diethyl ether complex ¹³
It is a graph which shows the measurement result of a C-NMR spectrum.
The numbers on the horizontal axis are the chemical shifts with respect to the peak of tetramethylsilane (TMS), which is an internal standard, expressed in ppm. In the boron trifluoride diethyl ether complex coordinated at a molar ratio of 1.0: 1.0, two peaks derived from carbon of diethyl ether were found at 12.9 ppm and 69.9 ppm in ¹³ C-NMR measurement. Is detected. As the molar ratio changes, the two peaks shift, but for the reconstituted boron trifluoride diethyl etherate
^{When 13} C-NMR measurement was performed, a peak was observed at the same position as the detection peak of the unused complex catalyst, and it was found that the same molar ratio as before the reaction was maintained.

(Recyclability of complex catalyst)
100 g of isooctane as a diluting solvent is charged and placed in a flask.
While stirring and maintaining at -25 ° C, isobutene 100g
Is newly supplied into the container, and then
Collected and reconstituted boron trifluoride diethyl ether complex
It was charged in a container to perform a polymerization reaction. Once after reaction
4.59 g of calcium fluoride (boron trifluoride)
And the mixture is stirred for 30 minutes.
Was. The same treatment is performed after the adsorption, and the conversion rate and yield
I asked. Distillation of reaction mixture and heat removal of adsorbent
The dressing process and the like were performed under the same conditions as the first time. The above three foot
The operation of recovering boron iodide is repeated three times, and four continuous polymerizations
The reaction was carried out, and the isobutane in the first and fourth reactions was
Conversion of polythene, yield of polyisobutene, and recovered
Table 1 shows the ratio (recovery rate) to the amount of charged complex catalyst.
Show. Table 1Number of reactions Isobutene conversion Polyisobutene yield Complex catalyst recovery rate  1 98.0% by mole 94.7% by weight 98.5% 4 97.7% by mole 93.8% by weight 98.2%

Example 2 A polymerization reaction was carried out in the same manner as in Example 1.
After the reaction is completed, the adsorbent to be added is calcium fluoride.
Was changed to strontium fluoride. That is, the reaction
After completion, 7.39 g of strontium fluoride (e.g.
In the same manner as in Example 1
Adsorption was performed. After the adsorption, the same treatment as in Example 1 is performed.
Conversion of isobutene and yield of polybutylene formed.
I asked. The subsequent distillation of the reaction mixture was the same as in Example 1.
Perform under the same conditions to remove boron trifluoride from the adsorbent by heating.
Change the processing temperature when wearing from 270 ° C to 320 ° C
went. Repeat the above boron trifluoride recovery operation three times
Then, the polymerization reaction is continuously performed four times, and the first and fourth polymerization reactions are performed.
Conversion of isobutene in the reaction of
Table 2 shows the yield and the recovery of the complex catalyst. Table 2Number of reactions Isobutene conversion Polyisobutene yield Complex catalyst recovery rate  1 97.5% by mole 94.1% by weight 65.3% 4 97.8% by mole 94.8% by weight 63.9%

Example 3 A polymerization reaction was carried out in the same manner as in Example 1.
And add strontium fluoride to be added after the end of the reaction.
The weight was changed. That is, after the reaction is completed,
14.80 g (corresponding to 8 times mol of boron trifluoride)
Amount) was added, and adsorption was performed in the same manner as in Example 1. That
Subsequent distillation of the reaction mixture and trifluoridation from the adsorbent
The thermal desorption of boron was performed in the same manner as in Example 2. The above three
The operation of recovering boron fluoride is repeated three times, and four times
A polymerization reaction was carried out, and the reaction in the first and fourth reactions was performed.
Sobutene conversion, yield of polyisobutene and complex catalyst
Table 3 shows the recovery of the medium. Table 3Number of reactions Isobutene conversion Polyisobutene yield Complex catalyst recovery rate  1 97.9% by mole 94.1% by weight 98.3% 4 98.0% by mole 94.0% by weight 97.1%

Example 4 Boron trifluoride as a complex catalyst
1.69 g of an ethanolic complex (1: 1 mol adduct) was added.
A polymerization reaction was performed in the same manner as in Example 1. After the reaction
In the same manner as in Example 1, 4.59 g of calcium fluoride (3
(Equivalent to 4 times the molar amount of boron fluoride).
The adsorption was performed for 0 minutes. Distillation of reaction mixture after adsorption
Treatment and thermal desorption of boron trifluoride from adsorbent
Performed in the same manner as in Example 1 to recover ethanol and trifluoride.
Again between boron, the boron trifluoride ethanol complex
Prepared. Repeat the above boron trifluoride recovery operation three times
Then, the polymerization reaction was performed four times in succession, and the first and fourth
Conversion of isobutene in eye reaction, polyisobutene
Table 4 shows the yield and the recovery of the complex catalyst. Table 4Number of reactions Isobutene conversion Polyisobutene yield Complex catalyst recovery rate  1 98.2% by mole 95.1% by weight 98.5% 4 98.1% by mole 95.0% by weight 97.4%

Example 5 Using isobutane as a solvent,
Polymerization of isobutene was carried out in the same manner as in Example 1. That is,
20.0 g of isobutene diluted with isobutane was
And keep it at -25 ° C.
Boron fluoride diethyl ether complex (1: 1 mole addition
Thing) 1.64g is added and vigorously stirred for 30 minutes
A polymerization reaction was performed. After completion of the reaction,
4.59 g of calcium iodide (5 times mol of boron trifluoride
) And stirred for 30 minutes to perform adsorption.
Was. After the adsorption, the recovery operation of boron trifluoride was performed in the same manner as in Example 1.
The reaction is repeated three times, and the polymerization reaction is continuously performed four times.
Conversion of isobutene in the 4th and 4th reactions
Table 5 shows the yield of lysobutene and the recovery of the complex catalyst.
You. Table 5Number of reactions Isobutene conversion Polyisobutene yield Complex catalyst recovery rate  1 98.2% by mole 95.1% by weight 97.9% 4 98.1% by mole 95.2% by weight 98.1%

<Comparative Examples 1 to 5> In Comparative Examples 1 to 5, polymerization was carried out under the same conditions as in the first polymerization reaction in Examples 1 to 5, respectively. Did not do. As a result, when the temperature is maintained after the reaction, the boron trifluoride-based complex catalyst is kept dispersed in the reaction solution containing polyisobutene in any case, and sedimentation of the complex catalyst occurs as it is. Did not.

Comparative Example 6 5% by weight of acrylonitrile
1% by weight, based on acrylonitrile, of tert-butyl peroxide and 0.5% of acrylonitrile as a polymerization initiator were added to a toluene solution.
By weight, thiourea was dissolved, and the obtained solution was impregnated with 60-80 mesh activated carbon previously dried at 150 ° C., and heated at 100 ° C. for 2 hours in a nitrogen stream to perform polymerization. After the heating was completed, washing with toluene heated to the boiling point was performed to remove unreacted acrylonitrile and low-polymerized products. In Example 1, boron trifluoride was adsorbed in the same manner except that the same weight of the activated carbon carrying the acrylonitrile polymer obtained above was charged instead of calcium fluoride. When the adsorption efficiency of boron trifluoride was determined, it was 2.6 g / 100 g-activated carbon, and it was confirmed that the adsorption efficiency was low.

Comparative Example 7 (Adsorption Removal of Boron Trifluoride) In Example 1, powdered potassium fluoride 3.4 was used instead of calcium fluoride.
The adsorption of boron trifluoride was performed in the same manner except that 3 g (equivalent to 4 times the molar amount of boron trifluoride charged) was added. As a result, adsorption was performed at an efficiency of 4.7 g / 100 g-potassium fluoride, and it was confirmed that the adsorption efficiency was low. (Heat Desorption) As in Example 1, the potassium fluoride adsorbent on which boron trifluoride was partially adsorbed and held was subjected to heat desorption. The heating temperature was initially maintained at 270 ° C., but almost no white smoke due to boron trifluoride was observed from the outlet. Then, when the heating temperature was gradually increased, white smoke was detected at the outlet from when the temperature reached a high temperature of about 700 ° C.

Comparative Example 8 (Adsorption Removal of Boron Trifluoride) In Example 1, the same volume of silica gel 1.15 was used instead of calcium fluoride.
The adsorption of boron trifluoride was performed in the same manner as in Example 1 except that g was added. As a result, although adsorbed at an efficiency of 8.5 g / 100 g-silica gel, a boron trifluoride complex released in the reaction mixture was detected, confirming that the adsorption efficiency was low. Furthermore, it was confirmed that HF gas was released in the gas phase of the reaction mixture during the adsorption. In addition, when the silica gel adsorbent, to which boron trifluoride was considered to be adsorbed and held, was subjected to photoelectron spectroscopy (ESCA) analysis, the adsorbent contained fluorine and boron in an atomic molar ratio of 2: 1.
And it was confirmed that the form of boron trifluoride (BF ₃ ) was not retained. That is, by reacting the silanol groups in the silica gel during adsorption (-SiOH groups) and boron trifluoride, probably because decomposed into HF gas free and ₂ group -SiOBF, reusable boron trifluoride recovered It turned out to be impossible.

[0070]

According to the method for producing polybutylene of the present invention, by using a metal fluoride as an adsorbent,
From a polymerization product obtained by polymerizing a C ₄ olefin or a hydrocarbon mixture containing a C ₄ olefin, a boron trifluoride complex catalyst comprising boron trifluoride used as a polymerization catalyst and a complexing agent is converted into a highly efficient boron trifluoride complex catalyst. And can be used repeatedly many times without impairing the activity, which can contribute to a reduction in catalyst cost in the production of polybutylene. Further, in the conventional process, when separating and removing the used catalyst, a method of neutralizing with an aqueous solution of a basic substance such as ammonia or caustic soda and washing with water is adopted. A large amount of wastewater containing fluoride, which is a neutralized product of boron trifluoride, was discharged. However, according to the method of the present invention, by recovering the catalyst at a high rate, the wastewater accompanying the treatment of industrial waste, etc. Environmental pollution problems can be greatly reduced.

[Brief description of the drawings]

FIG. 1. ¹³ C- before and after use in the reaction of boron trifluoride diethyl etherate complex and after recovery
It is a graph which shows the measurement result of an NMR spectrum.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) // C07B 61/00 300 C07B 61/00 300 F term (reference) 4H006 AA02 AC21 AD17 BA31 BA37 BA39 BA43 BA45 BA46 BA48 BA67 BA83 BA84 BC32 BD36 BD52 BE61 4H039 CA29 CF10 CL19 4J015 DA14

Claims (9)

[Claims] 1. A method for producing polybutylene, including the steps from the following (I) (III), a C ₄ olefin in the presence of a boron trifluoride-based complex catalyst consisting (I) boron trifluoride and a complexing agent A liquid phase polymerization step, (II) after polymerization of the C ₄ olefin, a metal fluoride represented by the following formula (1) is added to a reaction mixture obtained by dispersing and / or dissolving at least a part of the boron trifluoride-based complex catalyst. In order to selectively adsorb boron trifluoride (BF ₃ ) in the complex catalyst, MF _n ... Formula (1) (1) M represents a metal atom of lithium, calcium, strontium or barium, n = 1 or 2) (III) A step of recovering a reaction mixture containing a complexing agent from which boron trifluoride has been adsorbed and removed. 2. A method for producing polybutylene comprising the following steps (I) to (V): (I) a process for producing a C ₄ olefin in the presence of a boron trifluoride-based complex catalyst comprising boron trifluoride and a complexing agent; A liquid phase polymerization step, (II) after polymerization of the C ₄ olefin, a metal fluoride represented by the following formula (1) is added to a reaction mixture obtained by dispersing and / or dissolving at least a part of the boron trifluoride-based complex catalyst. In order to selectively adsorb boron trifluoride (BF ₃ ) in the complex catalyst, MF _n ... Formula (1) (1) M represents a metal atom of lithium, calcium, strontium or barium, n = 1 or 2) (III) a step of recovering a reaction mixture containing a complexing agent from which boron trifluoride has been adsorbed and removed, (IV) a step of recovering Obtained by adsorbing boron fluoride on metal fluoride Step serial formula tetrafluoroborate metal salt shown in (2) to give the boron trifluoride and the metal fluoride by heating at a temperature range of _{160~600 ℃, M (BF 4)} n ···· (2) (M represents a metal atom of lithium, calcium, strontium or barium. N = 1 or 2) (V) At least a part of the collected boron trifluoride as the catalyst, the step of the C ₄ olefins to liquid phase polymerization. 3. A process for producing polybutylene comprising the following steps (I) to (VI): (I) a process for producing a C ₄ olefin in the presence of a boron trifluoride-based complex catalyst comprising boron trifluoride and a complexing agent; A liquid phase polymerization step, (II) after polymerization of the C ₄ olefin, a metal fluoride represented by the following formula (1) is added to a reaction mixture obtained by dispersing and / or dissolving at least a part of the boron trifluoride-based complex catalyst. In order to selectively adsorb boron trifluoride (BF ₃ ) in the complex catalyst, MF _n ... Formula (1) (1) M represents a metal atom of lithium, calcium, strontium or barium, n = 1 or 2) (III) a step of recovering a reaction mixture containing a complexing agent from which boron trifluoride has been adsorbed and removed, (IV) a step of recovering Under the condition obtained by adsorbing boron fluoride on metal fluoride The boron tetrafluoride metal salt represented by the formula (2) to obtain a boron trifluoride and the metal fluoride by heating at a temperature range of _{160~600 ℃, M (BF 4)} n ····· (2) (M represents a metal atom of lithium, calcium, strontium or barium. N = 1 or 2) (V) In the step (II), the trifluoride in the complex catalyst is used. Recovering the complexing agent released into the reaction mixture when the boron fluoride is adsorbed, (VI) the boron trifluoride recovered from the step (IV) and the complexing agent recovered from the step (V) A new boron trifluoride complex catalyst is formed using at least a part of each of the above, and a liquid phase polymerization of C ₄ olefin as a polymerization catalyst. 4. C _{4 in} feedstock in said liquid phase polymerization
The olefin concentration is at least 5% by weight.
4. The method for producing polybutylene according to any one of items 1 to 3. 5. The temperature of the reaction mixture brought into contact with said metal fluoride is from -100 ° C. to + 160 ° C., preferably -3 ° C.
The method for producing polybutylene according to any one of claims 1 to 3, wherein the temperature is in a range of 0 ° C to + 50 ° C. 6. The method according to claim 6, wherein the boron tetrafluoride metal salt (M (BF ₄ ) _n ) formed by the adsorption of boron trifluoride is 100 to
The method for producing polybutylene according to claim 2 or 3, wherein the polybutylene is decomposed into boron trifluoride and metal fluoride by heating in a temperature range of 600 ° C, preferably 160 to 500 ° C. 7. The complexing agent forming the boron trifluoride-based complex catalyst includes water, alcohols, ethers, phenols, ketones, aldehydes, esters, organic acids, acid anhydrides and the like. The compound according to any one of claims 1 to 3, wherein the compound is selected from the group consisting of organic or inorganic polar compounds, such as an oxygen compound, a nitrogen-containing compound, a sulfur-containing compound, a phosphorus-containing compound, or an inorganic acid. A method for producing polybutylene. 8. The boron trifluoride complex catalyst according to claim 1, wherein the molar ratio of boron trifluoride to the complexing agent is in the range of 0.01: 1 to 2: 1.
The method for producing polybutylene according to any one of the above. 9. The polybutylene having a molecular weight of 100 to 1
The method for producing polybutylene according to any one of claims 1 to 3, wherein the number is in the range of 10,000.