JP5808693B2 - Olefin dehalogenation treatment method and olefin continuous polymerization method using an object to be treated - Google Patents

Description

  The present invention provides a method for removing a small amount of fluorine remaining as an impurity in an olefinic compound in the form of an organic substance, an inorganic substance, or a mixture thereof using an alumina-containing inorganic treatment agent.

  Patent Document 1 proposes to obtain a butene polymer containing a high proportion of molecules having a terminal vinylidene structure by polymerizing isobutene using a boron trifluoride complex catalyst having an alcohol as a complexing agent. Yes. A butene polymer containing a high proportion of these terminal double bonds is industrially useful because the maleation reaction proceeds at a high reaction rate with maleic anhydride and the like. The maleated butene polymer is finally used as an additive for fuel oil or lubricating oil.

  When the above-mentioned butene polymer is produced, the unreacted C4 fraction remaining without being used in the reaction is generally burned directly as a fuel, or 1-butene or a useful monomer as a comonomer for adjusting the density of high-density polyethylene. After 2-butene useful as a raw material for propylene production by the metathesis reaction is separated and removed, it is also used as a fuel or reused as a raw material for butene polymer production.

  However, the remaining so-called butadiene raffinate obtained by extracting butadiene from the C4 fraction obtained from naphtha cracking, and the C4 fraction in which the n-butene concentration is reduced by rectifying butadiene raffinate are used as the isobutene raw material to complex the alcohol. In the case of polymerization using a boron trifluoride complex catalyst as an agent, fluorine derived from boron trifluoride as a catalyst remains in the unreacted C4 fraction. In the case of using unreacted C4 fraction as fuel, this residual fluorine may act as a reaction inhibitor when reused as a raw material for butene polymer from the viewpoint of environmental load. When mixed in the fraction, it becomes a problem. In addition, although the boron trifluoride complex catalyst which uses alcohol as a complexing agent was described as an example, chlorine may remain even when isobutene is polymerized with an aluminum halide catalyst typified by aluminum chloride. There's a problem.

  Here, for example, in Patent Document 2, the residual fluorine concentration is reduced by washing the unreacted C4 fraction with water. However, the method of washing with water proposed in the above publication has a drawback that only a part of the residual fluorine component can be reduced.

  There are roughly two types of fluorine components that can remain in the unreacted C4 fraction. One is a water-soluble catalyst residue, and the other is fluorine existing as an organic molecule having a C—F bond directly bonded to C4. When the unreacted C4 fraction proposed in Patent Document 3 is washed with water, the remaining fluorine component that can be removed by the treatment is only the water-soluble catalyst residue. That is, there is a problem that the remaining fluorine in the unreacted C4 fraction in the form of organic molecules having a C—F bond cannot be removed only by washing with water.

U.S. Pat.No. 4,605,808 Special Publication No. 2003-513119 Japanese Patent Publication No.6-28725

  An object of the present invention is to provide an unreacted C4 fraction separated from a product when a polymerization reaction is carried out using a C4 fraction as a raw material using a halogen-containing catalyst, for example, a fluorine-containing Lewis acid catalyst. Industrially useful method for removing not only water-soluble catalyst residues of inorganic halogen compounds but also organic halogen compounds present as organic molecules having a C—F bond, etc. Is to provide.

  As already described, only by washing the unreacted C4 fraction containing residual fluorine with water, the fluorine present as an inorganic substance can be removed. The present inventors have found that both the inorganic halogen compound and the organic halogen compound can be removed by bringing unreacted isobutene into contact with an alumina-containing inorganic treatment agent. Completed.

That is, the present invention provides a reaction mixture by polymerizing an olefin in the presence of a Lewis acid catalyst containing fluorine in an inert organic solvent, separating the catalyst from the reaction mixture, and / or the reaction mixture . In a process for producing polyolefins, wherein the catalyst is deactivated in the reaction mixture obtained by distillation from the resulting reaction mixture, and contains a trace amount of fluorine distilled off from the reaction mixture from which the catalyst has been separated and / or deactivated. An unreacted olefin or an (unreacted) olefin and an inert organic solvent (hereinafter simply referred to as “olefin or olefin and an inert organic solvent”) are components represented by a composition formula Al2O3 of a defluorinating agent in a liquid phase. in contact with an inorganic solid treating agent containing a contact temperature with the inorganic solid treating agent and distilling off the olefin or the olefin and inert organic solvents 1 In the purification method of olefin to be defluorinated or olefin and inert organic solvent at 0 to 200 ° C., excluding the case where an organic basic compound containing ammonia or organic amine coexists in the defluorination treatment The present invention relates to the purification method .
The present invention also relates to an olefin whose defluorinating agent is alumina, or a method for purifying olefin and an inert organic solvent.
The present invention also relates to an olefin in which the Lewis acid containing halogen is boron trifluoride, or a method for purifying an olefin and an inert organic solvent.

The present invention also provides: a) polymerizing an olefin in the presence of a Lewis acid catalyst containing fluorine in an inert organic solvent to produce a reaction mixture, b) separating the catalyst from the reaction mixture, and / or A step of deactivating the catalyst in the reaction mixture; c) a method for producing a polyolefin by obtaining a polymer from the obtained reaction mixture through a distillation step, wherein the catalyst is separated and / or deactivated. The olefin or olefin and inert organic solvent containing a trace amount of fluorine distilled off from the liquid is brought into contact with an inorganic solid processing agent containing a component represented by the composition formula Al2O3 of the defluorinating agent in a liquid phase, and defluorinated. treated, the contact temperature with the inorganic solid treating agent and distilling off the olefin or the olefin and inert organic solvent traces after defluorination treatment is 10 to 200 ° C. Tsu containing oxygen, an olefin or olefin and inert organic solvent used as part of the raw materials, the production method of the polyolefin, during the defluorination process, coexist organic basic compound containing ammonia or organic amines, The present invention relates to the manufacturing method excluding cases .
The present invention also relates to a method for producing a polyolefin wherein the fluorine agent is alumina.
The present invention also relates to a method for producing a polyolefin, wherein the fluorine-containing Lewis acid is boron trifluoride .
The present invention also relates to a process for producing a polyolefin, wherein the polyolefin is a butene polymer, in particular a highly reactive butene polymer having a number average molecular weight Mn of 500 to 5000 Daltons and a terminal double bond content of more than 80 mol%. About.

  According to the method of the present invention, not only fluorine compounds remaining in the form of inorganic substances but also fluorine compounds remaining in the form of organic substances from the unreacted C4 fraction during the production of polyisobutene containing residual halogen, for example, residual fluorine as impurities. It is possible to remove. Moreover, it is possible to produce polyisobutene continuously by returning the unreacted C4 fraction subjected to the dehalogenation treatment to the polymerization apparatus. In addition, since the method of the present invention has extremely excellent halogen removal performance, the industrial utility is very high. Therefore, according to the method of the present invention, halogen can be efficiently and economically removed from an unreacted gas at the time of producing a butene polymer containing residual halogen as an impurity, and recovered butene can be reused.

Hereinafter, the present invention will be described in more detail.
The olefin to be treated in the present invention, or the olefin and the inert organic solvent contain a trace amount of a halogen compound such as a fluorine compound and a chlorine compound as impurities that can be adsorbed on alumina. If the organic compound is inert to alumina, the organic compound can have heteroatoms such as oxygen and phosphorus and various functional groups such as an aromatic ring in the molecule.

Examples of the inert organic solvent are preferably saturated hydrocarbons such as butane, pentane, hexane, heptane, octane, such as n-hexane, i-octane, cyclo-butane or cyclopentane, halogenated carbonization. Hydrogen, such as methyl chloride, dichloromethane or trichloromethane and mixtures of said compounds.
Examples of the olefin include unsaturated hydrocarbons having at least one non-conjugated carbon-carbon double bond. Examples of such olefinic compounds include 1-butene, 2-methyl-1-butene. Low molecular weight monoolefins such as 3-methyl-1-butene, 1-pentene, 1-hexene, vinylcyclohexane, 4-methyl-1-pentene, 2,4,4-trimethyl-1-pentene and 1-decene. Illustrated.

In addition, a trace amount of halogen compounds as impurities contained in the organic compound is mainly generated due to the halogen-containing catalyst used in the reaction using the organic compound, but other than the catalyst in the raw material. In some cases, it is caused by impurities.
In the case of a fluorine compound, there are inorganic fluorine compounds, organic fluorine compounds, or a mixture thereof. For example, inorganic fluorine compounds such as hydrogen fluoride, boron trifluoride, and silicon tetrafluoride, and 2-fluoro-2,4 An organic fluorine compound such as 1,4-trimethylpentane can be mentioned, but it is not particularly limited thereto.
In addition, when the halogen is chlorine, there are inorganic chlorine compounds, organic chlorine compounds, or mixtures thereof. For example, inorganic chlorine compounds such as hydrogen chloride and aluminum chloride, 2-chloro-2,4,4-trimethylpentane, and the like. And organic chlorine compounds.
The content of these halogen compounds, such as fluorine compounds, is usually very small, and the boiling point is close to the boiling point of the organic compound, so that it is difficult to separate and remove by ordinary separation means such as distillation.

  Although the amount of the halogen compound contained in a trace amount is not particularly limited, it is generally at most several hundred ppm by mass in terms of halogen atoms, and may be contained up to several percent by mass in some cases. Since both are so-called impurities with respect to the main organic compound, they must be removed as described above. In general, it is difficult to remove a halogen compound having a ppm level content due to its small amount, but the method of the present invention can be preferably applied to such a low content.

  Among the olefins used in the present invention, as the unreacted C4 fraction, the unreacted product at the time of producing the butene polymer having a terminal double bond obtained by polymerizing the C4 fraction with a fluorine-containing catalyst as described above is used. Can be mentioned. This unreacted C4 fraction contains fluorine as an impurity in terms of fluorine atoms of several ppm by mass or more, usually about 5 to 30 ppm by mass, and the fluorine forms an organic fluorine compound, specifically, a fluorinated hydrocarbon. It is thought that there is.

Next, production of the butene polymer will be described.
The butene polymer is produced by continuously polymerizing isobutene or a C4 feedstock containing it in a polymerization zone (reaction zone) equipped with a reactor. As the continuous reactor, any type capable of performing appropriate heat removal and stirring, such as a stirring reactor and a loop reactor, can be adopted. From the polymerization zone, a reaction solution containing unreacted components, the produced butene polymer and the catalyst flows out.

Typical examples of C4 feedstock include crackers that thermally crack hydrocarbons such as naphtha, kerosene, light oil, butane, etc., or fluid catalytic cracking (FCC) equipment that catalytically cracks to produce lower olefins such as ethylene and propylene. From the C4 fraction flowing out from the reactor, one obtained by removing butadiene by extraction or the like (butadiene raffinate), and further purifying butadiene raffinate, a C4 fraction having an increased isobutene concentration is assumed.
The typical composition of the C4 fraction is about 0.1 to 40% by weight, preferably about 0.1 to 20% by weight of 1-butene, about 0.1 to 1% by weight of 2- Butene, about 10-80% by weight, preferably about 40-70% by weight isobutene, and less than about 10% by weight, preferably about 0.5% by weight or less butadiene, and about 10-60% by weight as a saturated component. It consists of butanes (the total of C4 fractions is 100% by mass). It is not particularly limited as long as it is within this composition range, and may be a C4 fraction containing isobutene contained in cracking products and the like from FCC as described above in addition to crackers.
In addition, as long as it exists in the said composition range, what changed the composition by the appropriate means can also be used. Specifically, the composition is changed by distillation, isobutene is added to increase the isobutene concentration, isobutene is oligomerized by light polymerization to reduce the isobutene concentration, or a reaction such as catalytic hydroisomerization is performed. -What reduced butene density | concentration, what changed the composition by various physical or chemical operation, etc. can be used.
The C4 fraction is more preferable as the isobutene content is larger. However, even in butadiene raffinate, for example, the content of isobutene is about 70% by mass at maximum. The C4 fraction from FCC etc. is usually even lower.

A fluorine-containing catalyst is used as a catalyst in the isobutene polymerization reaction. In this case, a trace amount of a fluorine compound is mixed in the product butene polymer.
In addition, a chlorine-containing catalyst represented by aluminum chloride can also be used, and in this case, a chlorine compound is mixed as an impurity.
The fluorine-containing catalyst to be used is not particularly limited as long as a trace amount of a fluorine compound is mixed into the product by use. Specifically, in addition to a boron trifluoride-based catalyst, a catalyst obtained by contacting a divalent nickel compound with hydrocarbyl aluminum halide and trifluoroacetic acid, for example, nickel-heptanoate, dichloroethylaluminum, and trifluoroacetic acid Those formed by the action are exemplified. This divalent nickel-based fluorine-containing catalyst has been proposed in JP-A-57-183726.

  A preferred fluorine-containing catalyst is a boron trifluoride catalyst. In this case, boron trifluoride is fed into the polymerization zone at a ratio of 0.1 to 500 mmol with respect to 1 mol of raw material isobutene. The molecular weight of the butene polymer obtained by this method can be adjusted by adjusting the reaction temperature and the amount of catalyst input. If the amount of boron trifluoride as the catalyst is less than this range, the reaction is difficult to proceed. On the other hand, if it is more than this range, the molecular weight of the butene polymer becomes low and the catalyst cost increases, which is not economical.

  A more preferable boron trifluoride-based catalyst is a complex catalyst using an oxygen-containing compound as a complexing agent. Examples of the oxygen-containing compound that forms a complex with boron trifluoride include water, alcohols, ethers such as dialkyl ethers. Water, alcohols, dialkyl ethers or a mixture thereof can be supplied to the polymerization zone as a complexing agent at a ratio of 0.1 to 10 mol in total with respect to 1 mol of the halogen-containing catalyst as a catalyst. If the amount of the complexing agent is more than this range, the reaction is difficult to proceed, while if it is less than this range, side reactions and the like frequently occur.

All of the above water, alcohols, dialkyl ethers and the like form a complex with boron trifluoride in the reaction system. Therefore, a method comprising separately preparing a complex composed of a complexing agent such as water, alcohols, dialkyl ethers or a mixture thereof and boron trifluoride outside the polymerization zone and supplying this to the reaction system is adopted. However, a method in which boron trifluoride and the complexing agent are separately supplied to form a complex in the polymerization zone can also be adopted as one of the polymerization modes of the present application. Even when boron trifluoride and the complexing agent are separately supplied to the polymerization system in this way, the supply ratio of boron trifluoride, water, alcohols and dialkyl ethers as complex components to the C4 hydrocarbon feedstock is , Each can be in the same range as described above.
In order to produce a butene polymer with stable properties by quickly responding to fluctuations in moisture and isobutene concentration in the raw material, the amount of boron trifluoride and the molar ratio with the complexing agent must be quickly adjusted to the above changes. Adjustment is advantageous. For this purpose, a method of supplying the complexing agent to the reaction system separately from boron trifluoride as described above, or a complex having a high boron trifluoride concentration in which boron trifluoride and a small amount of complexing agent are mixed in advance. It is more preferable to adjust the amount of the complexing agent and the complexing agent separately.

Specific alcohols and dialkyl ethers as complexing agents are as follows.
Examples of alcohols include aromatic or C1-C20 aliphatic alcohols, specifically, methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol or benzyl alcohol, cyclohexanol. 1,4-butanediol and the like. The carbon skeleton of the C1-C20 aliphatic alcohols is not limited in the degree of branching, and may be a linear alkyl group, a branched alkyl group such as sec- or tert- or an alicyclic alkyl group, or an alkyl group containing a ring. There is no problem. These alcohols can be used alone or mixed at an appropriate ratio.

Examples of the dialkyl ethers include dialkyl ethers having the same or different aromatic or C1-C20 aliphatic hydrocarbon groups. 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 , Diphenyl ether, cyclohexyl methyl ether, cyclohexyl ethyl ether and the like. The backbone of the C1-C20 hydrocarbon group is not limited in the degree of branching, and may be a linear alkyl group, a branched alkyl group such as sec- or tert- or an alicyclic alkyl group, or an alkyl group containing a ring. . These dialkyl ethers can be used alone or in admixture at an appropriate ratio.
Note that one or more complexing agents such as water, the above alcohols, and dialkyl ethers can be mixed and used at an appropriate ratio.

  The polymerization with a boron trifluoride catalyst is liquid phase polymerization, and the polymerization temperature is in the range of −100 ° C. to + 50 ° C., preferably −50 ° C. to + 20 ° C. Below this range, the polymerization rate of isobutene is suppressed. On the other hand, at higher temperatures, side reactions such as isomerization and rearrangement occur frequently.

The polymerization method can be a butene polymer having a high content of terminal double bonds, either batchwise or continuously. However, since the continuous process is more economical and efficient from the viewpoint of industrial production, the following description will be given by taking continuous polymerization as an example. In general, the contact time of the feedstock with the catalyst is important in the continuous system, and in the polymerization reaction according to the present invention, the contact time is desirably in the range of 5 minutes to 4 hours.
If the contact time is less than 5 minutes, sufficient conversion of isobutene cannot be obtained, and excessive equipment is required to remove reaction heat. On the other hand, if it exceeds 4 hours, there are many economical losses and contact with the catalyst for a long time, so that side reactions such as isomerization and rearrangement of the produced butene polymer are promoted. Therefore, either case is not preferable.

  After the polymerization, the reaction solution containing unreacted components and the generated butene polymer and catalyst flows out from the polymerization zone as described above. In the next step, the catalyst is deactivated with an appropriate deactivator, for example, water, alkaline water, alcohol, etc., for the reaction solution according to a conventional method. After deactivation of the catalyst, neutralization and water washing are performed as necessary to remove the catalyst residue, and distillation is performed appropriately to remove the unreacted C4 fraction to obtain a butene polymer. The butene polymer thus obtained can be further divided into a light part and a heavy part, usually by distillation under reduced pressure as appropriate.

As described above, boron trifluoride is used as a polymerization catalyst, and water, alcohol, dialkyl ether or the like is used as a complexing agent, and isobutene is subjected to liquid phase polymerization, preferably in the range of 500 to 5,000 daltons, and more. Preferably a butene having a number average molecular weight Mn in the range of 300 to 3,000 daltons and containing a high proportion of terminal double bonds to all terminal groups, preferably 60 mol% or more, more preferably 80 mol% or more. A polymer can be obtained. However, in the unreacted C4 fraction separated from the polymer in the distillation step, the residual fluorine derived from the catalyst has a concentration of 1 ppm by mass or more in terms of fluorine atoms, usually 5 ppm by mass or more, and sometimes up to several hundred ppm by mass. Included. This residual fluorine is an organic fluorine that is difficult to remove even if it is deactivated and subsequently washed with water by a conventional method.
Next, the alumina treatment for defluorination performed in the present invention will be described.

In the present invention, the halogen compound contained in the organic compound is removed by contacting with a dehalogenating agent. The dehalogenating agent is preferably a treating agent containing aluminum atoms. In this case, the halogen atom in the halogen compound is immobilized in the treatment agent containing aluminum, and as a result, halogen removal is performed. The treatment agent containing an aluminum atom is more preferably an inorganic solid treatment agent containing a component represented by the composition formula Al2O3. As long as the component represented by Al2O3 is included, a natural or synthetic inorganic substance can be used. Specific examples of the inorganic solid treatment agent include alumina and silica / alumina.
More preferred is alumina. These may be molded using an appropriate binder. For example, commercially available alumina can be appropriately pulverized and classified for use. Although the surface area as a solid processing agent is not specifically limited, Usually, it is the range of 1-500 m < ² > / g.
In addition, unless the effect of the present invention is hindered, the alumina is appropriately impregnated with an alkali metal, alkaline earth metal or other metal in an oxide, hydroxide or other form, or appropriately supported by other methods. A modified one can also be used. However, normally, such loading / modification is not particularly required, and alumina having an alkali metal or alkaline earth metal content such as sodium of 0.5% by weight or less is used. Thus, alumina with little or no loading / modification is inexpensive, and the present invention is an advantageous method also in this respect.

  The olefin, or olefin and inert organic solvent, and the dehalogenating agent are contacted in the liquid phase. Contact in the gas phase is not efficient due to the short contact time. The temperature at which the olefin or the olefin and the inert organic solvent are brought into contact varies depending on the kind of the treating agent and the residual amount of halogen in the olefin or the olefin and the inert organic solvent to be contacted. Preferably it is 10-300 degreeC, More preferably, it is the range of 10-200 degreeC. If the treatment temperature is higher than this range, the energy required for the treatment becomes too large and the economic efficiency is lowered. On the other hand, if the temperature is low, the residual halogen concentration cannot be reduced or a sufficient reduction effect cannot be obtained. Therefore, neither is preferable.

The contact time between the dehalogenating agent and the olefin, or the olefin and the inert organic solvent is preferably in the range of 1 minute to 10 hours, more preferably 30 minutes to 5 hours. When it is shorter than this range, contact is generally insufficient, and when it is longer, the equipment cost increases, which is not preferable.
As a method for contacting, either a batch type or a continuous type is possible. In the case of a continuous type, a fixed bed type, a fluidized bed type or the like can be used. As the flow direction, either an upflow or a downflow can be adopted.
If the dehalogenation apparatus using the present invention is operated at around room temperature and with a contact time of about 1 hour, continuous operation for one year or more can be easily performed, and the industrial utility of the present invention is extremely high.

The olefin or the olefin and the inert organic solvent subjected to the defluorination treatment by contact with the dehalogenating agent in this way can be burned as fuel as they are or reused as a reaction raw material. For example, for the C4 fraction, as described above, after separating and removing 1-butene useful as a comonomer for adjusting the density of high-density polyethylene and 2-butene useful as a raw material for propylene production by metathesis reaction, It can be used as a fuel or reused as a raw material for butene polymer production.
By the dehalogenation treatment of the present invention, the residual halogen concentration in the unreacted C4 fraction is reduced to 1 mass ppm or less, preferably less than 1 mass ppm in terms of halogen atoms.
In this way, since, for example, fluorine is not substantially present as residual halogen, when the obtained unreacted C4 fraction is combusted, release of halogen, for example fluorine, into the atmosphere is small, so that environmental conservation is not necessary. It is also useful in terms of the aspect. Moreover, when reusing as a raw material for butene polymer production, it can be used without inhibiting the reaction.

<Example 1>
(Polymerization process)
A 0.5 liter continuous tank reactor was fed with a mixture of isobutene, isobutane, and C4 fraction butadiene raffinate from an ethylene cracker at 1.5 liters per hour, and 3 parts per mole of isobutene. A boron trifluoride methanol complex prepared in advance so that the amount of boron fluoride was 0.7 mmol so that methanol was 2 mol with respect to 1 mol of boron trifluoride was supplied to the reaction vessel. Polymerization was continuously carried out at a reaction temperature of -10 ° C. The composition of the raw materials used is shown in Table 1. Analysis was performed by gas chromatography (the same applies hereinafter).

(Polymer properties)
Unreacted feed and light components were distilled off from the organic phase obtained in the polymerization step by vacuum distillation. The molecular weight and terminal double bond content of the butene polymer obtained from the remaining product were determined. The molecular weight of the butene polymer was determined by gel permeation chromatography (GPC), and the identification and quantification of the molecular skeleton and the olefin structure at the molecular terminal were performed by measurement with a nuclear magnetic resonance apparatus (NMR). The number average molecular weight Mn of the obtained butene polymer was 960, and the amount of terminal double bonds was 88 mol%.

(De-C4 gas process)
The reaction liquid obtained in the above polymerization step was received in a container and allowed to stand to separate from the polymer that produced the unreacted C4 gas component and recovered. As a result of analyzing the recovered unreacted C4 gas component, the residual fluorine concentration was 7 ppm. The composition is shown in Table 2. The residual fluorine concentration was measured using an ion chromatograph after burning the unreacted C4 gas component with a wick bolt combustion apparatus and absorbing it in the absorbent.
The unreacted gas was analyzed using a gas chromatograph mass spectrometer (GC-mass spectroscopy), and a peak of mass number 76 indicating the presence of fluorine-bound C4 molecules was confirmed.

(Defluorination process)
Next, activated alumina (La Roche Chemicals, trade name: A-203 Cl) dried at 110 ° C. for 24 hours is pulverized into a 0.25 liter flow-through reaction tube having a fluid inlet at the top and a fluid outlet at the bottom. Then, the particles classified into particle diameters of 2 mm to 3.5 mm were filled, and a line for supplying the previously collected unreacted C4 gas was attached to the fluid inlet of the flow type reaction tube. The reaction tube temperature is 20 ° C., the flow rate of unreacted C4 gas is 20 g / hour so that the contact time is 4 hours, and after starting the defluorination treatment, the outlet gas is sampled up to 2,000 hours every arbitrary time. The composition of C4 component and residual fluorine concentration were measured.
Table 3 shows the residual fluorine concentration and composition after treatment after oil passage for 2,000 hours.

  Table 4 shows the residual fluorine concentration after treatment after each oil passage time.

<Example 2>
The reaction tube temperature was 180 ° C., and the defluorination treatment was performed in the same manner as in Example 1 except that. The composition of the C4 component after the treatment was not changed compared with that before the treatment, and the residual fluorine concentration was 1 ppm by mass or less.

<Example 3>
The contact time was set to 30 minutes, and the defluorination treatment was performed in the same manner as in Example 1 except that. The composition of the C4 component after the treatment was not changed compared with that before the treatment, and the residual fluorine concentration was 1 ppm by mass or less.

<Comparative Example 1>
Instead of alumina, silica gel (trade name: Silbead N, manufactured by Mizusawa Chemical Co., Ltd.) preliminarily heated and dried at 150 ° C. in a dry nitrogen stream was filled in the reaction tube, and the other cases were the same as in Example 1. Then, defluorination treatment was performed.
The composition of the C4 component after the treatment was not changed as compared with that before the treatment, and the residual fluorine concentration was 7 ppm by mass even 20 hours after the start of the treatment, and the removal effect was not obtained.

  In the case where the residual halogen concentration in the unreacted C4 fraction separated from the product is reduced when a polymerization reaction is carried out using a halogen-containing catalyst and a C4 fraction mainly containing isobutene monomer as a raw material, Use of high-purity regenerated olefins that do not contain halogens, which may not only prevent halogenated halogen compounds but also remove organic halogenated compounds and increase the environmental impact in reusing unreacted olefins. To be served.

Claims (8)

a) in the presence of a Lewis acid catalyst containing an inert organic solvent fluorine, process for producing the reaction mixture by polymerizing an olefin, b) the catalyst was separated from the reaction mixture, and / or the reaction mixture The olefin distilled off from the reaction mixture in the step c), which is included in the method for producing a polyolefin comprising the step of deactivating the catalyst in step c), and the step of obtaining the polymer by distillation from the reaction mixture obtained. Alternatively, in the method for purifying an olefin and an inert organic solvent , the olefin or olefin and the inert organic solvent containing a trace amount of fluorine distilled off from the reaction mixture separated and / or deactivated as described above is liquid phase. in in contact with the defluorination agent, and defluorination treatment, an inorganic solid treating agent containing a component the defluorination agent represented by the composition formula Al2O3, before The contact temperature of the inorganic solid treating agent and distilling off the olefin or the olefin and inert organic solvent Ru der 10 to 200 ° C., containing fluorine traces in the olefin or olefins and purification method of an inert organic solvent, wherein Except when ammonia or an organic basic compound containing an organic amine coexists in the defluorination treatment . The method for purifying an olefin or an olefin and an inert organic solvent containing a trace amount of fluorine according to claim 1, wherein the defluorinating agent is alumina. The method for purifying an olefin or an olefin and an inert organic solvent containing a trace amount of fluorine according to claim 1 or 2 , wherein the Lewis acid containing fluorine is boron trifluoride. a) polymerizing an olefin in the presence of a Lewis acid catalyst containing fluorine in an inert organic solvent to produce a reaction mixture; b) separating the catalyst from the reaction mixture and / or in the reaction mixture; C) a step of deactivating the catalyst, and c) a distillation process from the resulting reaction mixture to obtain a polymer. In the polyolefin production method, the catalyst is separated and / or distilled off from the deactivated reaction mixture. The olefin or olefin containing a trace amount of fluorine and an inert organic solvent are brought into contact with an inorganic solid processing agent containing a component represented by the composition formula Al2O3 of the defluorinating agent in a liquid phase, defluorinated, and the inorganic the contact temperature of the solid processing agent and distilling off the olefin or the olefin and inert organic solvent containing a fluorine traces after defluorination treatment is 10 to 200 ° C., The olefin or olefins and inert organic solvent used as part of the raw materials, the production method of the polyolefin, during the defluorination process, except when ammonia or organic basic compound containing an organic amine, coexist. The method for producing a polyolefin according to claim 4, wherein the fluorine agent is alumina. The method for producing a polyolefin according to claim 4 or 5, wherein the Lewis acid containing fluorine is boron trifluoride . The method for producing a polyolefin according to any one of claims 4 to 6 , wherein the polyolefin is a butene polymer. The method for producing a polyolefin according to claim 7 , wherein the polyolefin is a highly reactive butene polymer having a number average molecular weight Mn of 500 to 5,000 daltons and having a content of terminal double bonds exceeding 80 mol%.