JP2001062202A - Method for purifying solvent containing component derived from metallocene compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reuse a solvent containing components derived from a metallocene compound as impurities by bringing the solvent into contact with an adsorbent to adsorb and remove the components. SOLUTION: When components derived from a metallocene compound are efficiently removed from a solvent used in the production of a metallocene compound-containing catalyst or in olefin polymerization using the catalyst, the solvent containing the components as impurities is purified by contact with an adsorbent. This adsorbent is preferably an SiO2-base adsorbent such as a silica gel adsorbent, an alumina-silica gel adsorbent or a synthetic zeolite (molecular sieve) adsorbent. These absorbents may be used independently, or (a combination ...) a combination of two or more such adsorbents may be used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for purifying a solvent containing a component derived from a metallocene compound. Specifically, a metallocene compound-derived component is adsorbed,
The present invention relates to a method for purifying a solvent containing a component derived from a metallocene compound by adsorbing and removing the solvent preferably having a SiO ₂ composition. Also, the present invention
The present invention also relates to a method for reusing a solvent containing a component derived from a metallocene compound.

[0002]

2. Description of the Related Art In recent years, in catalytic polymerization of olefins,
From the viewpoint of high activity or high selectivity, using a metallocene compound as a transition metal component,
In a broad sense, there is an interest in using so-called metallocene-based catalysts (alumoxane compounds are typical as the organoaluminum compound component of the Ziegler-type catalyst), which can be classified as a Ziegler-type catalyst.
On the other hand, a Ziegler-type catalyst in a narrow sense, which typically uses a titanium halide compound (an example of which is supported on a magnesium carrier) instead of a metallocene compound as a transition metal compound component, is also intended to be produced. It is still used depending on the characteristics of the polyolefin.

[0003] In a business where the olefin polymerization process using a metallocene catalyst and the olefin polymerization process using a Ziegler-based catalyst in a narrow sense are also performed, it is economically feasible to use the recovered and purified solvent between both polymerization processes. Often possible.

However, in a recovered solvent containing a metallocene compound-derived component, a trace amount of a metallocene compound-derived component, for example, a cyclopentadienyl compound, inevitably remains in a conventional solvent purification method. When used for olefin polymerization using a titanium halide catalyst (for example, a titanium trichloride catalyst or a magnesium-supported Ziegler catalyst), the catalyst is denatured to lower the polymerization activity or consumes H ₂ commonly used in the polymerization system. Therefore, there has been a problem that the MFR control as the purpose becomes difficult. It can be sufficiently expected that the same trouble can occur in olefin polymerization using a metallocene catalyst when a recovery solvent containing a component derived from a metallocene compound is used.

On the other hand, conventionally, as a method for purifying a solvent used in the production of a Ziegler-based catalyst or a solvent used in olefin polymerization using this catalyst, hydrolysis, standing separation, distillation, and / or a dehydration step are used. , The catalyst residue mixed in the solvent or the residue of the organoaluminum compound used as a cocatalyst has been separated and removed. However, such a conventional purification method cannot sufficiently remove the components derived from the metallocene compound contained in the solvent, and thus it has been difficult to solve the above-described problems.

For this reason, conventionally, such a solvent containing a component derived from a metallocene compound has been limited to incineration without reuse, or to use in a specific field where the above-mentioned problems other than polymerization do not occur. Was.

[0007] Therefore, there has been a demand for a method of removing a metallocene compound-derived component contained in a solvent, purifying the solvent, and reusing the solvent.

[0008]

SUMMARY OF THE INVENTION The present invention makes it possible to efficiently remove a metallocene compound-derived component from a solvent containing a metallocene compound-derived component as an impurity, thereby making the solvent reusable. It is an object of the present invention to provide a method for purifying a solvent.

[0009]

The present invention SUMMARY OF] a particular adsorbent, typically adsorbent having SiO ₂ composition, the use of the metallocene compound derived component contained in the solvent to the adsorbent It is based on the finding that the metallocene compound-derived component can be efficiently removed from the solvent by selective adsorption.

<Summary> That is, the purification method of the present invention comprises:
A solvent containing a metallocene compound-derived component as an impurity is brought into contact with an adsorbent to adsorb and remove the metallocene compound-derived component.

<Effect> According to the purification method of the present invention, a solvent containing a component derived from a metallocene compound as an impurity (for example, a solvent used for the production of a catalyst containing a metallocene compound or an olefin polymerization using a catalyst containing a metallocene compound). From the solvent used), it is possible to efficiently remove the components derived from the metallocene compound, particularly cyclopentadienyl compounds, and from the solvent further containing other components such as organoaluminum, particularly cyclopentadienyl compounds. Dienyl compounds can be selectively removed. Thus, when using such a solvent, when polymerizing an olefin using a titanium halide-based catalyst such as a titanium trichloride catalyst or a magnesium-supported Ziegler catalyst, the polymerization activity is reduced, or such that MFR controlled by consuming H ₂ in or become difficult, can be overcome a problem so far. Therefore, by treating with the purification method of the present invention, or by using the method of the present invention, if necessary, in combination with conventional hydrolysis, stationary separation or separation operation by distillation, the solvent as described above. Can be reused.

[0012]

DETAILED DESCRIPTION OF THE INVENTION <Components Derived from Metallocene Compound> In the present invention, the components derived from metallocene compounds include any components derived from metallocene compounds (detailed later). You. Here, the components derived from the metallocene compound include, in addition to the metallocene compound obtained from a commercially available product or the compound having a metallocene ligand obtained by production, the metallocene compound in the production step and / or during use of the metallocene compound. Derivatives resulting from various chemical reactions and / or physical actions are also included. Examples of such a component include compounds derived from a cyclopentadienyl-type bonding group constituting a metallocene ligand in a metallocene compound (sometimes referred to as cyclopentadienyl compounds in the present invention). In general,
For example, a substituted or unsubstituted cyclopentadiene compound, a dimer thereof, or an oxide thereof may be mentioned. In the present invention, in particular, such a metallocene compound-derived component is contained in a solvent used for producing a catalyst containing a metallocene compound or a solvent used in olefin polymerization using a catalyst containing a metallocene compound. Is preferred. The details of these solvents will be described later.

In the present invention, the term “metallocene compound” refers to a substituted or unsubstituted cyclopentadienyl-based ligand.
Refers to a transition metal compound of Group 3 or 4 of the Long Periodic Table having one or two or a cationic complex thereof. Such a compound is specifically a compound represented by the following general formula [1] or [2]. ^{_{(CpR 1 a H 5-a}} ) m (CpR 2 b H 5-b) n MX q ··· [1] [(CpR 1 a H 5-a) m (CpR 2 b H 5-b) n MX _q L _c ] ^{z +} [Y] ^z -... [2]

Here, (CpR ¹ _a H _5-a ) and (CpR ²
_{bH5 -b} ) represents a cyclopentadienyl group and a derivative thereof, respectively. Among them, Cp represents a cyclopentadienyl-type binding group, and H represents hydrogen. R ¹ and R ^{2 each} have 1 to 1 carbon atoms
Up to 20 optionally substituted hydrocarbon groups, silicon-containing substituents, nitrogen-containing substituents, or oxygen-containing substituents, each of which may be the same or different. Also, R
¹ and R ² may bond to each other to form a ring, or may bond to each other to form a bridge. a and b are from 0 to 5
Is an integer up to. Further, m and n are integers of 0 to 2, and m + n is 1 or 2.

M represents a transition metal atom of Group 3 or 4 of the Long Periodic Table. X represents an optionally substituted hydrocarbon group having 1 to 20 carbon atoms, a hydrogen atom, a halogen atom,
A silicon-containing substituent, an alkoxy group, an allyloxy group, an amide group or a thioalkoxy group. X may be bonded to R ^1, R ^{2, can} also be a R 1, ^{R 2} itself. Further, a plurality of Xs may be mutually bonded to form a bidentate ligand. q satisfies q + m + n = V when the metallocene compound is represented by the formula [1], and when the metallocene compound is represented by the formula [2], q + m + n = It is a positive integer satisfying Vz.

L represents an electrically neutral ligand, and specific examples thereof include ethers, nitriles, amides, phosphines, and amines. c is the number and 0
Or indicates a positive integer. Y represents one or more anions that neutralize the cation, and the sum of the valences of the ions corresponds to z. Specific examples of Y include borates and phosphates.

<Solvent Containing a Component Derived from a Metallocene Compound> In the present invention, the solvent containing a component derived from a metallocene compound includes any solvent containing the component derived from a metallocene compound as an impurity. . In a preferred embodiment of the present invention, the solvent containing such a metallocene compound-derived component is a solvent used for producing a catalyst containing a metallocene compound, or a solvent used in olefin polymerization using a catalyst containing a metallocene compound. ,. That is, examples of the solvent containing such a metallocene compound-derived component include a medium component used in a process for producing a catalyst containing the metallocene compound or an olefin polymerization process.

In the present invention, the solvent containing such a metallocene compound-derived component is contained in the solvent used in the production process in addition to the various solvents used in the production process of the catalyst containing the metallocene compound as described above. Other raw material components and the like may also be included. Similarly, when the solvent is a solvent used in the olefin polymerization by the catalyst, the solvent may also include substances involved in the polymerization reaction such as a monomer used in the polymerization reaction and a manufactured polymer. it can.

<< Solvent used in the production of the catalyst containing the metallocene compound >> Accordingly, the solvent containing the component derived from the metallocene compound in the present invention is the solvent used in the production of the catalyst containing the metallocene compound, that is, It may be a solvent used and recovered in the process of producing a catalyst containing such a metallocene compound. As the solvent, particularly the medium component, used in the process of producing such a catalyst, an aliphatic compound, an alicyclic compound, a hydrocarbon compound such as an aromatic compound and the like are generally exemplified. Further, in the present invention, butane, pentane, hexane,
Heptane, octane, nonane, decane, cyclohexane, toluene, xylene and the like are preferred. These solvents (medium components) may be used alone or in combination of two or more. Hereinafter, a general production process of a catalyst containing a metallocene compound will be described.

The catalyst containing a metallocene compound referred to in the present invention can be obtained by combining the above metallocene compound alone with a co-catalyst, but in suspension polymerization or gas phase polymerization, the above metallocene compound is supported on a carrier. In general, a solid catalyst component is produced by this, and this is combined with a cocatalyst to form a polymerization catalyst.

Such a solid catalyst component can be produced by any known method using a solvent. Specifically, a method of producing a solid catalyst component by supporting a metallocene compound on an inorganic or organic solid carrier (for example, a method of supporting a metallocene compound on a solid support containing methylaluminoxane), an organic method in the presence of a solid support, A method for producing a solid catalyst component by contacting aluminum or a cation former and a metallocene compound with an olefin as needed, or a method for producing a solid catalyst component by contacting a clay compound with a metallocene compound, it can.

Here, the inorganic and organic solid carriers are:
Specifically, it is an inorganic compound such as silica, alumina, silica-alumina, a layered silicate, a clay compound or a metal salt, or an organic compound such as polyolefin particles or polystyrene particles. Preferred among these are ion-exchangeable layered silicates. Further, the surface area of these solid supports is preferably 10 m ² / g or more, more preferably 50 m ² / g or more.
m is ² / ^{g~500m 2} / g.

The ion-exchangeable layered silicate which is a preferable solid carrier is, for example, a known layered silicate described in a standard textbook "Clay Mineralogy" (Hario Shimizu, Asakura Shoten (1995)) and the like. Acid salts are exemplified. Specifically, examples of such an ion-exchange layered silicate include, for example,
(A) montmorillonite, zaukonite, beidellite, nontronite, saponite, hectorite, stevensite, smectite group such as bentonite or teniolite, (b) vermiculite group such as vermiculite, (c) mica, illite, sericite or sea green Examples include mica tribes such as stones.

When the inorganic and organic solid carriers are brought into contact with the metallocene compound, other components other than these two components, for example, siloxanes, organoaluminums, silicon halides or organosilicon compounds, are allowed to coexist as cocatalysts. Is also possible.

Specific examples of the organoaluminum compound used at this time include compounds represented by the following general formula. R ′ _3-r AlX _r or R ′ _3-s Al (OR ″) _s (where R ′ and R ″ are a hydrocarbon residue having 1 to 20 carbon atoms or a hydrogen atom, and X is a halogen And r and s are respectively 0 ≦ r <3 and 0 ≦ s <3).

Specifically, such organic aluminum compounds include (a) trimethylaluminum, triethylaluminum, tripropylaluminum, triisobutylaluminum, trihexylaluminum,
Trialkyl aluminum such as trioctyl aluminum and tridecyl aluminum; alkyl aluminum halides such as (ii) diethyl aluminum chloride, diisobutyl aluminum chloride, ethyl aluminum sesquichloride and ethyl aluminum dichloride; and (c) diethyl aluminum hydride and diisobutyl aluminum hydride Examples thereof include alkyl aluminum hydride, and (d) alkyl aluminum alkoxide such as diethyl aluminum ethoxide and diethyl aluminum phenoxide. In addition, alumoxanes such as methylalumoxane and isobutylalumoxane can also be used. These can be used alone or in combination of two or more. Of these, trialkyl aluminums are preferred.

The amount of such an organic ammonium compound to be used is generally Al / M = 0.1 to 100,000 mol / mol, preferably, in proportion to the transition metal compound (M) in the solid catalyst component. , Al / M = 1 to 10,000 mol / mol.

In the production of a catalyst containing a metallocene compound, the solid catalyst component and the ethylenically unsaturated compound can be prepolymerized. Such prepolymerization is
It is carried out by contacting the solid catalyst component containing the metallocene compound with an ethylenically unsaturated compound in the presence of an organoaluminum compound.

Specific examples of such an ethylenically unsaturated compound include (a) α-olefins such as ethylene, propylene, butene, pentene and hexene; and (b) styrene such as styrene and divinylbenzene. And (c) butenes such as butadiene, isoprene, 1,9-decadiene and 1,7-octadiene, and (d) cyclic olefins such as cyclopentene and norbornene. The prepolymerization is desirably performed so that about 0.01 to 1000 g, preferably about 0.1 to 100 g, of the polymer is produced per 1 g of the solid catalyst component.

Accordingly, the solvent containing the metallocene compound-derived component of the present invention may be, in addition to the metallocene compound-derived component, a solid carrier component, a cocatalyst component such as an organoaluminum compound, and / or an ethylenically unsaturated compound, May include a solvent (medium component) and the like.

<< Solvent Used in Olefin Polymerization Using Catalyst Containing Metallocene Compound >> The solvent containing a metallocene compound-derived component in the present invention is a solvent used in olefin polymerization using a catalyst containing a metallocene compound. That is, it can be a solvent used and recovered in an olefin polymerization process using a catalyst containing a metallocene compound as shown below. Hereinafter, a general olefin polymerization process using a catalyst containing a metallocene compound will be described.

General olefin polymerization using a catalyst containing a metallocene compound can be carried out in the presence of a solvent by combining the above-described solid catalyst component with a cocatalyst component such as an organoaluminum compound.

As the solvent, an inert hydrocarbon such as propane, butane, pentane, hexane, heptane, toluene and cyclohexane is generally used. Such solvents include those in the case where polymerization is carried out using the monomer used as a medium. Further, these solvents (mediums) may be used alone or in combination of two or more.

The olefins to be polymerized are represented by the general formula
The compound represented by R ³ —CH ＝ CH ₂ (where R ³ represents a hydrogen atom or a hydrocarbon residue having 1 to 10 carbon atoms) is usually used. Specific examples of such olefins include:
Ethylene, propylene, 1-butene, 1-pentene, 3
Examples include olefins such as -methylbutene-1,1-hexene, 4-methylpentene-1,1-octene or styrene. These can be combined with each other to perform random copolymerization and block copolymerization. General polymerization conditions for such olefin polymerization are such that the polymerization temperature is from 0 to 280C, preferably from 50 to 250C.
The polymerization pressure is usually in the range of 1 to 2000 kg / cm ² G.
In the polymerization, the molecular weight can be controlled by using a molecular weight regulator such as hydrogen, if necessary.

Accordingly, the solvent containing the metallocene compound-derived component of the present invention may be, in addition to the metallocene compound-derived component, a solid carrier component, a co-catalyst component such as an organoaluminum compound, a monomer component for polymerization, and / or And purified polymer components, as well as solvents (medium components)
Etc. can be included.

<Adsorbent> In the present invention, any adsorbent can be used as long as it has an adsorbing effect on the component derived from the metallocene compound. The components can be selectively adsorbed. Therefore, examples of such an adsorbent include those having activated carbon and SiO ₂ composition. Here, “having a SiO ₂ composition”
The term means a substance having a silicate structure in which a part of Si may be substituted with another element such as Al or Mg. In the present invention, an adsorbent having a SiO ₂ composition is preferred. Examples of such an adsorbent include silica gel, alumina-silica gel, synthetic zeolite (molecular sieve (hereinafter sometimes abbreviated as MS)), natural zeolite, and the like. In a preferred embodiment of the present invention, the adsorbent having such a SiO ₂ composition is preferably a silica gel-based adsorbent, an alumina-silica gel-based adsorbent, or a synthetic zeolite (molecular sieve) -based adsorbent. These adsorbents may be used alone or in combination of two or more.

The adsorbent used in the present invention preferably has an average pore diameter of 1 to 200 angstroms.
Those having a thickness of 100 to 100 angstroms are more preferred, and those having a thickness of 20 to 50 angstroms are still more preferred.

In the present invention, the adsorbent is usually used as a powder or granules. Therefore, when the obtained adsorbent substance is in the form of a lump, it can be used as it is, but may be used by pulverizing it if necessary. Alternatively, the powder of the adsorbent substance may be granulated by a conventional granulation means, for example, a method of granulating using a binder such as a natural clay substance or silica, and then used after being granulated. Furthermore, the adsorbent may be used in the form of, for example, a panel-like molded body in consideration of the conditions under which the present invention is carried out, the location, the shape of the container (device), and the like.

The amount of adsorbent used in the present invention is
It can be appropriately selected according to the type of the adsorbent to be used, the amount of the solvent to be purified, the concentration of the metallocene compound-derived component contained in the solvent, and the like.

<Solvent Purification Method> As described above, the solvent purification method of the present invention involves contacting a solvent containing a metallocene compound-derived component as an impurity with an adsorbent to adsorb and remove the metallocene compound-derived component. By doing so, the solvent is purified. In the purification of the solvent using the adsorbent of the present invention, a known solvent purification method can be employed. That is, for example, the present invention can be implemented by any of batch, continuous, and semi-batch operation methods.
Therefore, for example, when the batch operation is performed,
In addition to the operation performed once, a batch operation of performing multiple processes, a countercurrent multi-stage batch operation, and the like can be performed. Further, in the present invention, the fixed bed adsorption in which the adsorbent is used as a packed bed and the processing fluid is sent to perform the adsorption, the moving bed adsorption in which the adsorbent and the processing fluid are continuously moved in countercurrent to perform adsorption, and Any method such as layer adsorption, stirring tank adsorption method and the like can be carried out.

In the present invention, when an organic aluminum component is present in the solvent when introducing the solvent into the refining apparatus, it is preferable to decompose the organic aluminum component in advance using water, alcohol, or the like. At this time, it is preferable to further reduce and remove water, alcohol, and the like remaining in the solvent by distillation, adsorption, separation, or the like in advance.

In the present invention, the operating conditions (eg, operating temperature, operating pressure, operating time, etc.) of the refining operation using the adsorbent include the type of adsorbent used, the amount of adsorbent used,
Alternatively, it can be appropriately selected in consideration of the adsorption equilibrium of the used adsorbent. As specific operating conditions, for example, the operating temperature is −20 to 200 ° C., preferably room temperature to 120 ° C.
The operating pressure is usually in the range of 1 to 200 kg / cm ² G,
Preferably it is in the range of 1 to 50 kg / cm ² G.

In the present invention, if necessary, a conventional hydrolysis, stationary separation or distillation separation operation can be carried out in combination with the purification method of the present invention.

<Method for Reusing Solvent> The method for reusing a solvent containing a component derived from a metallocene compound as an impurity according to the present invention is a method for reusing a solvent for an olefin polymerization reaction using a nonmetallocene catalyst. A solvent containing a metallocene compound-derived component as an impurity, wherein the concentration of the metallocene compound-derived component in the solvent for polymerization reaction is 1 ppm by weight or less. Here, the non-metallocene catalyst refers to a catalyst other than a catalyst using a metallocene compound.For example, a titanium halide catalyst such as a titanium trichloride catalyst or a magnesium-supported Ziegler catalyst is used as such a catalyst. Is exemplified.

In the method of reusing a solvent according to the present invention, a component derived from a metallocene compound is contained as an impurity in at least a part of a solvent (solvent for polymerization reaction) used in conducting an olefin polymerization reaction using a nonmetallocene catalyst. The contained solvent is used. In a preferred embodiment of the present invention,
As the solvent used in this manner, a solvent containing a metallocene compound-derived component discharged in various steps, for example, a solvent used for producing a catalyst containing a metallocene compound, or a catalyst containing a metallocene compound was used. Solvents used in olefin polymerization.

The reuse method of the present invention uses a solvent containing such a metallocene compound-derived component as at least a part of the polymerization reaction solvent. The concentration of the component derived from the metallocene compound is preferably 1 ppm by weight or less, more preferably 0.5 ppm by weight or less. The concentration of the metallocene compound-derived component in the solvent to be reused is 1 ppm by weight.
The following is important for good olefin polymerization. Therefore, in the present invention, the concentration of the component derived from the metallocene compound in the solvent for the polymerization reaction is 1 wt.
m or less, in addition to the solvent containing the metallocene compound-derived component discharged in the various steps, other solvent components not containing the metallocene compound-derived component (for example, an unused solvent for the polymerization reaction), etc. It can further include.

In the method for reusing a solvent according to the present invention, the solvent containing a metallocene compound-derived component used as an impurity in the polymerization reaction solvent as an impurity is obtained by purifying by the above-described purifying method according to the present invention ( (A purified solvent). In such a case, as the polymerization reaction solvent, it is possible to use the purified solvent as it is, but the concentration of the metallocene compound-derived component in the purified solvent obtained by the purification method of the present invention is, for example, When the concentration is higher than 1 ppm by weight, the concentration of the metallocene compound-derived component in the polymerization reaction solvent is reduced to 1 wt.
m, preferably 0.5 ppm by weight or less.

[0048]

The following is a specific description of the present invention by showing examples of the present invention. The present invention is not limited to these.

In the present invention, the MFR value was determined by the following measuring device and measuring method. [MFR] Apparatus: Melt indexer manufactured by Takara Co., Ltd. Measurement method: Based on JIS-K6758.

In the following examples, the concentration of butylcyclopentadiene, which is a metallocene compound-derived component, was determined as follows. [Measurement method of butylcyclopentadiene concentration] The butylcyclopentadiene concentration was determined by gas chromatography. In the measurement, CP-Sil PONA CB was used as an analytical column.
Using φ0.21mm * 50m (manufactured by GL Sciences), initial temperature 30 ° C, final temperature 250 ° C, heating rate 2
A gas chromatographic analysis was performed at an injection temperature of 200 ° C./° C./min. The butylcyclopentadiene concentration was determined by a relative area comparison method using pyrene of a known concentration as an internal standard.

[Test A] A used solvent was obtained as follows, and the purification method of the present invention was applied thereto, and the result was evaluated using a polymerization reaction. <Example A-1><< Solvent (waste solvent) generated in the process of producing a catalyst containing a metallocene compound >> Demineralized water in which 0.2 kg of zinc sulfate is dissolved 3.
2 kg, synthetic mica (ME-10 manufactured by Corp Chemical Co., Ltd.)
0) 1 kg was dispersed, stirred at room temperature for 1 hour, and filtered. Next, after washing this synthetic mica with demineralized water, the slurry was adjusted so that the solid content concentration was 25%,
This slurry was introduced into a spray dryer to obtain spherical granulated particles. Further, the particles were dried under reduced pressure at 200 ° C. for 2 hours to obtain a carrier. Next, in a 10-liter autoclave sufficiently purged with nitrogen, fully purified n-heptane 4 was added.
One liter and 50 g of the carrier were introduced, and 200 mmol of triethylaluminum and 4 mmol of bis (n-butylcyclopentadienyl) zirconium dichloride were further introduced. Then, at 60 ° C., ethylene was introduced into the autoclave at a rate of 2.33 L / min for 2 hours for prepolymerization. After the completion of the reaction, the supernatant in the autoclave was decanted and separated. On the other hand, the remaining solid content was further dried under reduced pressure, and finally 395 g
Was obtained.

Next, the supernatant liquid 1
L was introduced into the flask, 1 L of water was added thereto, and the mixture was stirred at room temperature for 1 hour. The mixture was then distilled to recover heptane. As a result of the analysis, it was found that the recovered heptane contained butylcyclopentadiene in an amount of 150 ppm by weight.

<< Purification Treatment of Waste Solvent >> Into a flask purged with nitrogen, 500 ml of the above-mentioned recovered heptane was introduced, and then molecular sieve (M) dried under reduced pressure at 200 ° C. for 6 hours.
S13X) was introduced in an amount of 100 g. It was left at room temperature for 12 hours in a nitrogen atmosphere to perform a purification treatment. When butylcyclopentadiene contained in the recovered heptane after the molecular sieve treatment was measured, the butylcyclopentadiene concentration was reduced to 10 ppm by weight or less.

<< Polymerization Using Purified Waste Solvent (Titanium Trichloride Catalyst) >> A 3-liter autoclave having a stirring and temperature control device was replaced with propylene, and then sufficiently purified n-heptane. 5 liters were introduced. Next, the MS-treated waste liquid heptane 30 m
under a nitrogen atmosphere, 1 g of diethylaluminum chloride, 100 mg of titanium trichloride catalyst (manufactured by M & S) and 500 ml of hydrogen were introduced, and propylene was added to a total pressure of 7 kg / cm ² G Introduce 6
Polymerization was performed at 5 ° C. for 3 hours. As a result, 327.5 g of a product polymer was obtained. This product polymer has a melt flow rate (MFR) of 2.46 and a bulk density of 0.51.
It was 7. The amount of atactic polymer (AP) obtained by drying the polymerization filtrate was 2.97 g. Therefore, when the atactic polymer derivation ratio was calculated from the amount of the atactic polymer contained in the product polymer, it was 0.90. In addition, polymer bulk density (BD)
Was 0.517.

<Comparative Example A-1> Polymerization was carried out in the same manner as in Example A-1 except that no MS13X-treated waste liquid was added during polymerization to obtain a product polymer.

<Comparative Example A-2> The same as Example A-1 except that 30 ml of a waste solvent not subjected to purification treatment by MS13X (untreated waste liquid) was used in place of the MS13X-treated waste liquid during polymerization. Was polymerized to obtain a product polymer.

<Example A-2> In the same manner as in Example A-1, except that 5 ml of a waste solvent (untreated waste liquid) which had not been subjected to purification treatment by MS13X was used instead of the waste liquid treated with MS13X at the time of polymerization. Polymerization was performed to obtain a product polymer.

The results of Test A are shown in Table 1 below.

Table 1 : Effect of metallocene compound-derived components on polymerization (titanium trichloride catalyst system) Example A-1 Comparative Example A-1 Comparative Example A-2 Example A-2 Added waste liquid MS treated Not added Untreated waste liquid Untreated waste liquid waste liquid 30 ml 30 ml 5 ml Phylcyclopentacindiene in polymerization solvent <0.203. 0.5 Content (wtppm) Product polymer amount (g) 327.5 326.3 274.2 321.6 Polymerization activity 3300 3300 2800 3200 (g-PE / g-catalyst) AP amount (g) 2.97 3 .04 2.52 2.95 AP Derivation Rate (%) 0.90 0.92 0.91 0.91 MFR (g / 10min) 2.46 2.21 2.58 2.56 BD (g / cc ) 0.517 0.518 0.501 0.512

As is clear from the results shown in Table 1, in the polymerization using the titanium trichloride catalyst, the polymerization activity when the MS-treated waste solvent was used was the polymerization activity when the polymerization was carried out without adding the waste solvent. It was almost the same result. This indicates that the MS activity of the waste solvent improves the polymerization activity. Therefore, according to the purification method of the present invention,
It was found that the solvent containing the component derived from the metallocene compound was purified. From the above results, the content of the component derived from the metallocene compound in the polymerization solvent was small (for example, 0.1%).
(About 5 ppm by weight), the effect on the obtained polymer was very small, and it was found that this was a degree that could be used as a product.

[Test B] <Example B-1> A waste solvent was obtained in the same manner as in Example A-1, and the following polymerization test was carried out using the waste solvent.

<< Polymerization Using Purified Waste Solvent (Magnesium Chloride-Supported Titanium Catalyst System) >> The polymerization apparatus of Example A-1 was used to carry out propylene substitution in the same manner as in Example A-1, followed by sufficient purification. 1.5 liters of n-heptane were introduced. Then, 30 ml of the MS-treated waste liquid heptane of Example A-1 was added thereto, and triethylaluminum 38 was further added.
0 mg, 20 mg of titanium catalyst supported on magnesium chloride containing t-butylmethyldimethoxysilane, 1000 ml of hydrogen
Was introduced, propylene was introduced up to a total pressure of 7 kg / cm ² G, and polymerization was carried out at 75 ° C. for 3 hours. As a result, 339.2 g
Of the product polymer was obtained. MFR of this product polymer
Was 19.2 and bulk density was 0.479. The atactic polymer (AP) obtained by drying the polymerization filtrate was 1.32 g. Therefore, when the atactic polymer derivation ratio was calculated from the amount of the atactic polymer contained in the product polymer, it was 0.39.
In addition, the BD value was 0.479.

<Comparative Example B-1> Polymerization was carried out in the same manner as in Example B-1 except that the MS13X-treated waste liquid was not added during the polymerization to obtain a product polymer.

<Comparative Example B-2> The same as Example B-1 except that 30 ml of a waste solvent (untreated waste liquid) not subjected to purification treatment by MS13X was used instead of the waste liquid treated with MS13X at the time of polymerization. Was polymerized to obtain a product polymer.

<Example B-2> In the same manner as in Example B-1, except that 5 ml of a waste solvent (untreated waste liquid) not subjected to purification treatment by MS13X was used instead of the waste liquid treated with MS13X at the time of polymerization. Polymerization was performed to obtain a product polymer.

The results of Test B are shown in Table 2 below.

Table 2 : Effect of metallocene compound-derived components on polymerization (magnesium chloride-supported titanium catalyst system) Example B-1 Comparative Example B-1 Comparative Example B-2 Example B-2 Additive waste liquid MS treated Not added Untreated waste liquid Untreated waste liquid waste liquid 30 ml 30 ml 5 ml butylcyclopentacinediene in polymerization solvent <0.203. 0.5 Content (wtppm) Product polymer amount (g) 339.2 340.9 322.2 361.1 Catalytic activity 17000 17100 16200 18100 (g-PE / g-catalyst) AP amount (g) 1.32 1 .43 1.17 1.33 AP Derivation Rate (%) 0.39 0.42 0.36 0.37 MFR (g / 10 min) 19.2 19.4 10.8 18.3 BD (g / cc ) 0.479 0.479 0.471 0.473

As is clear from the results shown in Table 2 above, in the polymerization using the titanium catalyst supported on magnesium chloride, M
It was found that the MFR of the system using the waste solvent after the S treatment and the system without the waste solvent were maintained at substantially the same level, whereas the MFR of the system to which the untreated waste liquid was added was reduced.
Therefore, it was found that the solvent containing the metallocene compound-derived component was purified by the purification method of the present invention. Also, from the above results, if the content of the metallocene compound-derived component in the polymerization solvent is small (for example, about 0.5 ppm by weight), the effect on the obtained polymer is very small, and this is used as a product. It turned out to be possible.

[Test C: Comparative test of adsorbent]
-Butylcyclopentadienyl) hafnium dichloride (1.0 g) was dissolved in 500 ml of n-heptane with an equal amount of water, and the mixture was subjected to standing separation and dehydration treatment to prepare a model waste liquid (waste solvent). 100 ml of this model waste liquid
A predetermined amount of each of the following adsorbents, which was dried at 200 ° C. for 6 hours under reduced pressure, was introduced. After standing at room temperature overnight, the concentration of butylcyclopentadiene (BuCp) was measured. << Adsorbent used >>-Example C-1: Neobead-SA (manufactured by Mizusawa Chemical Co., Ltd.) [Silica-
Alumina adsorbent] ・ Example C-2: Neobead-SA (manufactured by Mizusawa Chemical) [Silica-
Alumina-based adsorbent] (However, in Example C-2, the regenerated product of Example C-1 was used as the adsorbent.) (Regeneration operation of the adsorbent: The used adsorbent was dried under reduced pressure at 200 ° C. for 6 hours.) Example C-3: Silbead-N (manufactured by Mizusawa Chemical Co., Ltd.) [Silica gel-based adsorbent]-Comparative Example C-1: Neobead-GB13 (manufactured by Mizusawa Chemical Co., Ltd.) [Alumina-based adsorbent]-Comparative Example C-2: Neobead -GB45 (manufactured by Mizusawa Chemical) [Alumina adsorbent]

The results of Test C are shown in Table 3 below.

Table 3 : Influence of purification agent on different adsorbents Example C-1 Example C-2 Example C-3 Comparative Example C-1 Comparative Example C-2 Adsorbent Neobead-SA Neobead-SA Silbead-N Neobead- Neobead- (recycled product) GB13 GB45 Adsorbent type silica-alumina silica -Alumina Silica gel Alumina Alumina adsorbent amount (g) 1.5 1.5 2.0 1.5 1.5 1.5 Initial BuCp 820 1070 820 820 480 Concentration (ppm) Final BuCp <10 110 <10 No decrease No decrease Concentration (ppm)

From the results shown in Table 3, it can be seen that the components derived from the metallocene compound in the solvent (waste solvent) are advantageously adsorbed and removed by the silica-alumina adsorbent and the silica gel adsorbent.

[0073]

According to the purification method of the present invention, components derived from metallocene compounds, particularly cyclopentadienyl compounds, can be efficiently and selectively removed from a solvent containing components derived from metallocene compounds as impurities. ,
When the olefin is polymerized using a titanium halide-based catalyst by further using the above-mentioned solvent, the MF may be reduced by lowering the polymerization activity or consuming H ₂ in the polymerization system.
The fact that the conventional problems such as the difficulty in controlling the R can be overcome has already been described in the section of [Summary of the Invention].

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) C08F 10/00 C08F 10/00 F term (reference) 4D017 AA03 BA04 CA05 4G066 AA12B AA22B AA30B AA61B 4J100 AA00P CA00 GA22 GD03

Claims (6)

[Claims] A solvent containing a metallocene compound-derived component as an impurity, wherein the solvent containing a metallocene compound-derived component as an impurity is brought into contact with an adsorbent to adsorb and remove the metallocene compound-derived component. Purification method. 2. The solvent containing a metallocene compound-derived component as an impurity is a solvent used for producing a catalyst containing a metallocene compound or a solvent used in olefin polymerization using a catalyst containing a metallocene compound. Item 7. The purification method according to Item 1. 3. The purification method according to claim 1, wherein the adsorbent has a SiO ₂ composition. 4. The method according to claim 3, wherein the adsorbent is a silica-alumina adsorbent, a silica gel adsorbent or a synthetic zeolite adsorbent. 5. A solvent containing a metallocene compound-derived component as an impurity is used as at least a part of a polymerization reaction solvent for performing an olefin polymerization reaction using a nonmetallocene catalyst. The method for use, wherein the concentration of the metallocene compound-derived component in the polymerization reaction solvent is 1 ppm by weight or less. 6. The solvent according to claim 1, wherein the solvent containing a component derived from the metallocene compound used as the solvent for the polymerization reaction is an impurity.
The reuse method according to claim 5, which is obtained by purification by the purification method according to any one of claims 4 to 4.