Method for producing magnesium-containing particles

Abstract

A method for producing Mg-containing particles by performing a classification process using a centrifugal airflow classifying device, the centrifugal airflow classifying device including: a housing; a rotating body that rotates within the housing; a classification chamber located on an outer edge side of the rotating body; and a flow path formed by an inner surface of the housing and a top surface of the rotating body, connecting an upstream end portion with the classification chamber, wherein the method for producing Mg-containing particles includes: supplying the unclassified Mg-containing particles to the classification chamber so that an average flow velocity of the unclassified Mg-containing particles on a downstream side from the upstream end portion in the flow path is lower than an average flow velocity of the unclassified Mg-containing particles at the upstream end portion flowing inside the flow path; and classifying the unclassified Mg-containing particles in the classification chamber to obtain Mg-containing particles, wherein an attrition durability A (%) of the unclassified Mg-containing particles calculated by the following formula (1) is 85 or less: A = (Z ÷ Y) x 100... (1).

Description

TECHNICAL FIELD

[0001] The present application relates to a method for producing Mg-containing particles with reduced content of fine coarse powder particles. BACKGROUND

[0002] In the past, as a component of a polymerization catalyst for use in a polymerization reaction of an olefin, a solid catalyst component for olefin polymerization (sometimes also referred to as "solid catalyst component") containing magnesium, titanium, an electron-donating compound, and halogen as essential components has been proposed, and in particular, a solid catalyst component prepared using an alkoxy magnesium compound typified by diethoxy magnesium as a magnesium raw material has high performance and has been widely used in industry.

[0003] For a catalyst for olefin polymerization (sometimes also referred to as "polymerization catalyst") prepared using such a solid catalyst component, fine powder particles and coarse powder particles (sometimes collectively referred to as "fine coarse powder component") generated in the preparation process thereof become a problem in the polymerization of an olefin.

[0004] That is, an olefin polymer polymerized using a solid catalyst component for olefin polymerization containing a fine coarse powder component contains the fine coarse powder component, but this becomes a cause of poor products of the olefin polymer. Therefore, in order to reduce such an olefin polymer in the form of fine coarse powder, it is required to reduce the fine coarse powder component in the solid catalyst component.

[0005] Generally, in the preparation of a solid catalyst component, a solvent is removed by reduced pressure drying or the like, and as a result, the fine coarse powder component is contained in the powder-like solid catalyst component after the removal of the solvent. Therefore, a method for removing the fine coarse powder component from the solid catalyst component after the removal of the solvent by performing sieving, fractionation, or the like on the solid catalyst component has been studied (for example, refer to Patent Document 1).

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 6-287225 SUMMARY

[0009] Problems to be Solved by the Invention

[0010] However, in the method described in Patent Document 1, in particular, the breakage of solid catalyst component particles that are small in particle strength and weak is significant, and the fraction yield of the obtained solid catalyst component is reduced, and therefore, it is difficult to say that the yield (product yield) of the solid catalyst component having a desired particle diameter is sufficiently high. Furthermore, if the yield of the solid catalyst component is reduced, this leads to an increase in manufacturing cost accordingly.

[0011] Further, the surface state of the obtained solid catalyst component particles is also deteriorated by the damage and abrasion, and in the case where such a solid catalyst component is supplied to the polymerization of an olefin, the solid catalyst particles sometimes cannot endure the expansion in the polymerization and are disintegrated. In addition, it also becomes one of the reasons for increasing the fine powdery polymer in the obtained olefin polymer.

[0012] On the other hand, in the sieving, the structure of the secondary particles formed by the combination of the particles is maintained, and the particles are not sufficiently separated as primary particles, and there is a problem that it is not suitable for the production of an olefin polymer.

[0013] The present application is accomplished in view of the above problems, and an object of the present application is to provide a method for producing Mg-containing particles, which can reduce the content of fine and coarse powder particles such as fine powder particles, and improve the yield of the product, and which has a narrow particle size distribution and a good particle shape.

[0014] Means for Solving the Problems

[0015] The above problem is solved by the following. That is, the method for producing Mg-containing particles of the present application (1) obtains Mg-containing particles by performing a classification treatment using a centrifugal airflow classifier device, the centrifugal airflow classifier device having: a housing; a rotating body that rotates within the housing; a classification chamber located on the outer edge side of the rotating body; and a flow path formed by the inner surface of the housing and the top surface of the rotating body, connecting an upstream end portion to the classification chamber, wherein

[0016] The method for producing Mg-containing particles includes the steps of: making the average flow rate of the unclassified Mg-containing particles on the downstream side from the upstream end portion in the flow path smaller than the average flow rate of the unclassified Mg-containing particles at the upstream end portion flowing inside the flow path, supplying the unclassified Mg-containing particles to the classification chamber; and classifying the unclassified Mg-containing particles in the classification chamber to obtain Mg-containing particles,

[0017] The abrasion durability A (%) of the unclassified Mg-containing particles calculated by the following formula (1) is 85 or less:

[0018] A = (Z ÷ Y) x 100 (1)

[0019] In the formula, Y represents the average particle size D 50 (μm) measured automatically in a dry manner at a blow pressure of 0.4 bar using a laser diffraction type particle size distribution measuring device, and Z represents the average particle size D 50 (μm) measured automatically in a dry manner at a blow pressure of 1.0 bar using the laser diffraction type particle size distribution measuring device.

[0020] Further, the method for producing Mg-containing particles according to the present application (2) is a method for producing Mg-containing particles according to (1), wherein

[0021] In the step of supplying the unclassified Mg-containing particles to the classification chamber, the average flow rate of the unclassified Mg-containing particles at the inlet of the classification chamber is 1 / 2 or less of the average flow rate of the unclassified Mg-containing particles at the upstream end portion.

[0022] Further, the method for producing Mg-containing particles according to the present application (3) is a method for producing Mg-containing particles according to (1) or (2), wherein

[0023] In the step of supplying the unclassified Mg-containing particles to the classification chamber, the average flow rate of the unclassified Mg-containing particles at the substantially middle position of the radius of the top surface of the rotating body is 2 / 3 or less of the average flow rate of the unclassified Mg-containing particles at the upstream end portion.

[0024] Further, the method for producing Mg-containing particles according to the present application (4) is a method for producing Mg-containing particles according to any one of (1) to (3), wherein

[0025] The average flow rate of the unclassified Mg-containing particles at the inlet of the classification chamber is 15 m / s or less.

[0026] The Mg-containing particle classification device according to the present application (5) classifies unclassified Mg-containing particles in a classification chamber provided below a drop inlet in a housing having the drop inlet on the outer edge side of a rotating classification rotor, and obtains Mg-containing particles, wherein

[0027] The Mg-containing particle classification device has a flow path defined by the housing and the top surface of the classification rotor, and connects the drop inlet and the classification chamber to reduce the flow rate of the unclassified Mg-containing particles flowing inside.

[0028] Further, the Mg-containing particle classification device according to the present application (6) is the Mg-containing particle classification device according to (5), wherein the flow path reduces the average flow rate of the unclassified Mg-containing particles at the inlet of the classification chamber to 1 / 2 or less of the average flow rate of the unclassified Mg-containing particles at the upstream end portion.

[0029] Further, the Mg-containing particle classification device according to the present application (7) is the Mg-containing particle classification device according to (5) or (6), wherein the flow path reduces the flow rate of the unclassified Mg-containing particles at the inlet of the classification chamber to 15 m / s or less.

[0030] Further, the Mg-containing particle classification device according to the present application (8) is the Mg-containing particle classification device according to any one of (5) to (7), wherein

[0031] The housing has:

[0032] a first portion provided to the housing in a position opposite to the top surface, at a first predetermined distance from the top surface; and

[0033] a second portion provided to the housing in a position opposite to the top surface and closer to the inlet port side than the first portion, at a second predetermined distance greater than the first predetermined distance from the top surface.

[0034] Further, the Mg-containing particle classifying device of the present application (9) is based on the Mg-containing particle classifying device described in (8),

[0035] The second portion is inclined away from the top surface as it gets closer to the inlet port.

[0036] Further, the Mg-containing particle classifying device of the present application (10) is based on the Mg-containing particle classifying device described in any one of (5) to (9),

[0037] The top surface is formed in a substantially flat shape.

[0038] Further, the Mg-containing particle classifying device of the present application (11) is based on the Mg-containing particle classifying device described in (10),

[0039] The substantially flat shape includes a frustum-shaped tapered portion in a position opposite to the inlet port.

[0040] Effects of the Invention

[0041] According to the present application, it is possible to provide a method for producing Mg-containing particles, which can reduce the content of fine and coarse powder particles, improve the yield of products, and have a narrow particle size distribution and good particle shape. BRIEF DESCRIPTION OF DRAWINGS

[0042] Fig. 1 is a cross-sectional view schematically showing the Mg-containing particle classifying device of the embodiment.

[0043] Fig. 2 is a cross-sectional view schematically showing the Mg-containing particle classifying device of the embodiment. Fig. 1 is a cross-sectional view showing the detailed structure of the flow path connecting the inlet port and the classifying chamber of the Mg-containing particle classifying device shown in

[0044] Fig. 3 is a cross-sectional view showing the inlet port, the classifying chamber, and the flow path of the Mg-containing particle classifying device shown in Fig. 1 and showing the A-A position and the B-B position.

[0045] Fig. 4 is a cross-sectional view showingFig. 1 A sectional view of the flow path of the Mg-containing particle classification device shown and indicating the C-C position and the D-D position, the E-E position, the F-F position.

[0046] Fig. 5 A sectional view indicating the detailed structure of the intake port, the classification chamber, and the flow path of the classification device of the reference embodiment.

[0047] Fig. 6 A sectional view indicating the detailed structure of the intake port, the classification chamber, and the flow path of the classification device of the reference embodiment. Fig. 5 A sectional view of the flow path of the classification device of the reference embodiment shown and indicating the A-A position and the B-B position.

[0048] Fig. 7 A sectional view indicating the detailed structure of the intake port, the classification chamber, and the flow path of the classification device of the reference embodiment. Fig. 1 A sectional view of the flow path of the classification device of the reference embodiment shown and indicating the C-C position and the D-D position, the E-E position, the F-F position.

[0049] Fig. 8 A perspective view indicating the plurality of dispersion vanes and the tapered portion of the top surface of the classification rotor of the classification device of the reference embodiment. Fig. 5 DETAILED DESCRIPTION

[0050] <Method for producing Mg-containing particles>

[0051] The method for producing Mg-containing particles of the present application obtains Mg-containing particles by performing a classification process using a centrifugal airflow classification device that has: a housing; a rotating body that rotates within the housing; a classification chamber that is located on the outer edge side of the rotating body; and a flow path that is formed by the inner surface of the housing and the top surface of the rotating body, connecting an upstream end portion to the classification chamber, wherein

[0052] The method for producing Mg-containing particles includes the steps of: making the flow rate of the unclassified Mg-containing particles on the downstream side from the upstream end portion in the flow path smaller than the flow rate of the unclassified Mg-containing particles at the upstream end portion of the flow path that flows inside the flow path, supplying the unclassified Mg-containing particles to the classification chamber; and classifying the unclassified Mg-containing particles in the classification chamber to obtain Mg-containing particles,

[0053] The attrition durability A (%) of the unclassified Mg-containing particles calculated by the following formula (1) is 85 or less:

[0054] A = (Z ÷ Y) x 100 (1)

[0055] In the formula, Y indicates the average particle diameter D50 measured by a dry automatic measurement using a laser diffraction type particle size distribution measuring device at a blow pressure of 0.4 bar.​50 (μm), Z represents the average particle diameter D 50 (μm).

[0056] In the manufacturing method of the Mg-containing particles of the present application, the unclassified Mg-containing particles are subjected to classification treatment using a centrifugal airflow classification device (described later) having a predetermined rotating body. That is, the unclassified Mg-containing particles are the treatment target of the classification treatment. Here, the unclassified Mg-containing particles refer to particles that include particles after dissociation of the aggregated state and particles that are weak and have a small particle strength (described later) of the aggregated particles that maintain the aggregated state. Also, in the manufacturing method of the Mg-containing particles of the present application, the particles that are subjected to the classification treatment of such unclassified Mg-containing particles are the Mg-containing particles. In addition, the object to be removed as "particles other than the Mg-containing particles" in the classification treatment is the fine powder described later. Note that, in the present specification, the "particles other than the Mg-containing particles" do not refer to particles that do not contain Mg (Mg-free particles). As the Mg-containing particles, the particulate magnesium compound, the particulate solid catalyst component for olefin polymerization, and the particulate solid catalyst for olefin polymerization described later can be listed, respectively. Note that, in the present application, the Mg-containing particles can be porous particles themselves or can include aggregates of particles having gaps (gaps between aggregated particles). Hereinafter, in the present application, the Mg-containing particles include the magnesium compound and the solid catalyst component for olefin polymerization (for example, a solid catalyst component for olefin polymerization that contains titanium, a halogen, and one or more internal electron donors together with the magnesium compound) that mainly include the magnesium compound. In addition, in the concept of the Mg-containing particles in the present application, particles of the solid catalyst component for olefin polymerization obtained using the above-described solid catalyst component for olefin polymerization, and particles of the catalyst for olefin polymerization that have an organoaluminum compound and an external electron donor compound as needed can also be included.

[0057] The solid catalyst component for olefin polymerization includes the magnesium compound as the main component, and the upper limit value of the magnesium compound in the Mg-containing particles is not particularly limited. The content ratio of the magnesium compound in the solid catalyst component for olefin polymerization is preferably 50% by mass or more, more preferably 60% by mass or more, further preferably 70% by mass or more, and still further preferably 75% by mass or more.

[0058] The magnesium compound is not particularly limited, and for example, one or more selected from the group consisting of magnesium dihalide, magnesium chloride·alcohol / water adduct, and the like can be listed.

[0059] The magnesium dihalide can be one or more selected from the group consisting of magnesium dichloride, magnesium dibromide, magnesium diiodide, and the like, and is preferably magnesium dichloride.

[0060] As the magnesium chloride-alcohol / water adduct, a magnesium compound-alcohol / water adduct represented by the following general formula (i) can be exemplified:

[0061] MgCl2-mROH-nH2O... (i)

[0062] In the formula, R is a hydrocarbon group having 1 to 10 carbon atoms, m is a real number of 2 to 4, and n is a real number of 0 to 0.7.

[0063] In the method for producing the Mg-containing particles according to the present application, the magnesium compound constituting the Mg-containing particles can be either prepared using magnesium alkoxide as a raw material or commercially available products can be used for the production of the Mg-containing particles.

[0064] The magnesium compound prepared using magnesium alkoxide as a raw material is likely to form particles containing coarse powder particles because the magnesium alkoxide particles are easily attached to each other at the time of production, but the particles are weak in strength and fragile, and thus the method according to the present application can be appropriately applied for classification.

[0065] In the method for producing the Mg-containing particles according to the present application, the Mg-containing particles are not particularly limited, and for example, a magnesium compound, an olefin polymerization solid catalyst component containing titanium, a halogen and one or more internal electron donors together with the above-described magnesium compound, and an olefin polymerization catalyst having the above-described olefin polymerization solid catalyst component, an organic aluminum compound and an external electron donor compound as needed can be exemplified. Among them, an olefin polymerization solid catalyst component is preferred. Further, the Mg-containing particles can also contain an olefin polymerization catalyst having the above-described olefin polymerization solid catalyst component, an organic aluminum compound and an external electron donor compound as needed.

[0066] In the method for producing the Mg-containing particles according to the present application, as the olefin polymerization solid catalyst component containing titanium, a halogen and one or more internal electron donors together with the above-described magnesium compound, a contact reaction product of magnesium alkoxide, a tetravalent titanium halide and an internal electron donor compound can be exemplified.

[0067] As the above-described magnesium alkoxide, a dialkylmagnesium can be exemplified.

[0068] As the above-described dialkylmagnesium, specifically, one or more selected from the group consisting of dimethylmagnesium, diethylmagnesium, dipropylmagnesium, dibutylmagnesium, ethoxymethylmagnesium, ethoxypropylmagnesium, butoxyethylmagnesium and the like can be exemplified, and diethylmagnesium is particularly preferred.

[0069] The above-described dialkylmagnesium can be obtained by reacting metallic magnesium with alcohol in the presence of a halogen or a halogen-containing metal compound or the like.

[0070] In the method for producing the Mg-containing particles according to the present application, the dialkylmagnesium is preferably spherical.

[0071] In the case where a spherical dialkylmagnesium is used as the dialkylmagnesium, a polymer powder having a more excellent particle shape (more spherical) and having a narrow particle size distribution can be obtained, the handling workability of the polymer powder generated at the time of polymerization operation is improved, and the occurrence of clogging and the like caused by fine powder contained in the generated polymer powder is easily suppressed.

[0072] In the method for producing the Mg-containing particles according to the present application, the magnesium compound is preferably in a solution or a suspension at the time of the reaction, and by being in a solution or a suspension, the reaction can be properly performed.

[0073] In the method for producing the Mg-containing particles according to the present application, as the tetravalent titanium halide, there is no particular limitation, and it is preferable to be one or more selected from the group of titanium halides or alkoxy titanium halides represented by the following general formula (I):

[0074] Ti(OR 1 ) r X 4-r …(I)

[0075] In the formula, R 1 represents an alkyl group having 1 to 4 carbon atoms, X represents halogen atoms which can be the same as or different from each other, such as chlorine atoms, bromine atoms, iodine atoms, and the like, and r is 0 or an integer of 1 to 3. In the case where OR 1 may be the same as or different from each other.

[0076] As the titanium halide, there can be mentioned titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, and the like.

[0077] Further, as the alkoxy titanium halide, there can be mentioned methoxy titanium trichloride, ethoxy titanium trichloride, propoxy titanium trichloride, n-butoxy titanium trichloride, dimethoxy titanium dichloride, diethoxy titanium dichloride, dipropoxy titanium dichloride, di-n-butoxy titanium dichloride, trimethoxy titanium chloride, triethoxy titanium chloride, tripropoxy titanium chloride, tri-n-butoxy titanium chloride, and the like.

[0078] As the tetravalent titanium halide, it is preferable to be a titanium tetrahalide, and more preferable to be titanium tetrachloride.

[0079] These titanium compounds can be used alone or in combination of two or more.

[0080] In the method for producing the Mg-containing particles according to the present application, as the internal electron-donating compound, there is no particular limitation, and it is preferable to be one or more selected from the group of monocarboxylic acid esters, dicarboxylic acid esters, monoethers, diethers, ether carboxylic acid esters, diol diesters, and ether carbonates, and further preferable to be one or more selected from the group of aromatic polycarboxylic acid esters such as aromatic dicarboxylic acid diesters, aliphatic polycarboxylic acid esters, alicyclic polycarboxylic acid esters, diethers, and ether carbonates.

[0081] In the production method of the Mg-containing particles according to the present application, as the aromatic dicarboxylic acid diester, a compound represented by the following general formula (II) can be exemplified:

[0082] (R 2 ) j C6H 4-j (COOR 3 )(COOR 4 )…(II)

[0083] In the formula, R 2 represents an alkyl group having 1 to 8 carbon atoms or a halogen atom, R 3 and R 4 are alkyl groups having 1 to 12 carbon atoms, and can be the same or different, and the number j of the substituents R 2 is 0, 1 or 2, and when j is 2, each R 2 can be the same or different.

[0084] In the aromatic dicarboxylic acid diester represented by the general formula (II), R 2 is a halogen atom or an alkyl group having 1 to 8 carbon atoms.

[0085] In the case where R 2 is a halogen atom, as the halogen atom, one or more atoms selected from a fluorine atom, a chlorine atom, a bromine atom and an iodine atom can be exemplified.

[0086] In the case where R 2 is an alkyl group having 1 to 8 carbon atoms, as the alkyl group having 1 to 8 carbon atoms, one or more selected from a methyl group, an ethyl group, a n-propyl group, an iso-propyl group, a n-butyl group, an iso-butyl group, a t-butyl group, a n-pentyl group, an iso-pentyl group, a neopentyl group, a n-hexyl group, an iso-hexyl group, a 2,2-dimethylbutyl group, a 2,2-dimethylpentyl group, an iso-octyl group and a 2,2-dimethylhexyl group can be exemplified.

[0087] As R 2 , a methyl group, a bromine atom and a fluorine atom are preferred, and a methyl group and a bromine atom are more preferred.

[0088] In the aromatic dicarboxylic acid diester represented by the general formula (II), R 3 and R 4 are alkyl groups having 1 to 12 carbon atoms, and R 3 and R 4 can be the same as or different from each other.

[0089] As the alkyl group having 1 to 12 carbon atoms, an ethyl group, a n-butyl group, an iso-butyl group, a t-butyl group, a neopentyl group, an iso-hexyl group and an iso-octyl group can be exemplified, and an ethyl group, a n-propyl group, a n-butyl group, an iso-butyl group or a neopentyl group is preferred.

[0090] In the aromatic dicarboxylic acid diester represented by General Formula (II), the substituent R 2 The number j is 0, 1, or 2, and when j is 2, each R 2 (2 R 2 ) can be the same or different.

[0091] When j is 0, the compound represented by General Formula (II) is a phthalic acid diester, and when j is 1 or 2, the compound represented by General Formula (II) is a substituted phthalic acid diester.

[0092] When j is 1, in the aromatic dicarboxylic acid diester represented by General Formula (II), it is preferable that R 2 be substituted for the hydrogen atoms at the 3-, 4-, or 5-position of the benzene ring.

[0093] When j is 2, in the aromatic dicarboxylic acid diester represented by General Formula (II), it is preferable that R 2 be substituted for the hydrogen atoms at the 4- and 5-position of the benzene ring.

[0094] As specific examples of the aromatic dicarboxylic acid diester represented by General Formula (II), there can be mentioned dimethyl phthalate, diethyl phthalate, di-n-propyl phthalate, diisopropyl phthalate, di-n-butyl phthalate, diisobutyl phthalate, di-n-pentyl phthalate, diisopentyl phthalate, diphenyl phthalate, di-n-hexyl phthalate, dimethyl phthalate, methyl ethyl phthalate, (ethyl) n-propyl phthalate, ethyl isopropyl phthalate, (ethyl) n-butyl phthalate, ethyl isobutyl phthalate, (ethyl) n-pentyl phthalate, ethyl isopentyl phthalate, ethyl phenyl phthalate, (ethyl) n-hexyl phthalate, and the like, phthalic acid diesters, diethyl 4-chlorophthalate, di-n-propyl 4-chlorophthalate, diisopropyl 4-chlorophthalate, di-n-butyl 4-chlorophthalate, diisobutyl 4-chlorophthalate, diethyl 4-bromophthalate, di-n-propyl 4-bromophthalate, diisopropyl 4-bromophthalate, di-n-butyl 4-bromophthalate, diisobutyl 4-bromophthalate, and the like, halogen-substituted phthalic acid diesters, diethyl 4-methylphthalate, di-n-propyl 4-methylphthalate, diisopropyl 4-methylphthalate, di-n-butyl 4-methylphthalate, diisobutyl 4-methylphthalate, and the like, alkyl-substituted phthalic acid diesters, and the like.

[0095] In the case where an aliphatic polycarboxylic acid ester is used as the internal electron-donating compound, as the aliphatic polycarboxylic acid ester, there can be mentioned a saturated aliphatic polycarboxylic acid ester, an unsaturated aliphatic polycarboxylic acid ester.

[0096] As the saturated aliphatic polycarboxylic acid ester, malonic acid diesters, succinic acid diesters, fumaric acid diesters, adipic acid diesters, glutaric acid diesters, and the like can be exemplified. More preferably, one or two or more kinds selected from the group consisting of malonic acid diesters, alkyl-substituted malonic acid diesters, alkylene-substituted malonic acid diesters, and succinic acid diesters are used.

[0097] Further, as the unsaturated aliphatic polycarboxylic acid ester, maleic acid diesters and the like can be exemplified, and more preferably one or two or more kinds selected from the group consisting of maleic acid diesters and alkyl-substituted maleic acid diesters are used.

[0098] In the case where succinic acid diesters are used as the internal electron-donating compound, as the succinic acid diesters, diethyl succinate, dibutyl succinate, diethyl methyl succinate, diethyl 2,3-diisopropyl succinate, and the like can be exemplified, and diethyl succinate or diethyl 2,3-diisopropyl succinate is preferred.

[0099] In the case where maleic acid diesters are used as the internal electron-donating compound, as the maleic acid diesters, diethyl maleate, di-n-butyl maleate, and diisobutyl maleate are preferred.

[0100] In the case where alkyl-substituted maleic acid diesters are used as the internal electron-donating compound, as the alkyl-substituted maleic acid diesters, dibutyl dimethyl maleate, dibutyl diethyl maleate, and diethyl diisobutyl maleate are preferred.

[0101] In the case where malonic acid diesters are used as the internal electron-donating compound, as the malonic acid diesters, dimethyl malonate, diethyl malonate, or diisobutyl malonate is preferred.

[0102] Further, as the internal electron-donating compound, substituted malonic acid diesters are preferred.

[0103] In the case where substituted malonic acid diesters are used as the internal electron-donating compound, as the substituted malonic acid diesters, alkyl-substituted malonic acid diesters and halogen-substituted malonic acid diesters are preferred, and alkyl-substituted malonic acid diesters are more preferred.

[0104] Further, as the alicyclic polycarboxylic acid ester, saturated alicyclic polycarboxylic acid esters and unsaturated alicyclic polycarboxylic acid esters can be exemplified. Specifically, cycloalkane dicarboxylic acid diesters, cycloalkene dicarboxylic acid diesters, and the like can be exemplified.

[0105] In the case of using a cycloalkane dicarboxylic acid diester as the internal electron-donating compound, as the cycloalkane dicarboxylic acid diester, cyclopentane-1,2-dicarboxylic acid diester, cyclopentane-1,3-dicarboxylic acid diester, cyclohexane-1,2-dicarboxylic acid diester, cyclohexane-1,3-dicarboxylic acid diester, cycloheptane-1,2-dicarboxylic acid diester, cycloheptane-1,2-dicarboxylic acid diester, cyclooctane-1,2-dicarboxylic acid diester, cyclooctane-1,3-dicarboxylic acid diester, cyclononane-1,2-dicarboxylic acid diester, cyclononane-1,3-dicarboxylic acid diester, cyclodecane-1,2-dicarboxylic acid diester, cyclodecane-1,3-dicarboxylic acid diester, and the like can be exemplified.

[0106] In the case of using a diether as the internal electron-donating compound, as the diether, a compound represented by the following general formula (III) can be used:

[0107] R 5 k H (3-k) C-O-(CR 6 R 7 ) p -O-CR 8 q H (3-q) …(III)

[0108] In the general formula (III), R 5 and R 8 are a halogen atom or an organic group having 1 to 20 carbon atoms, and can be the same as or different from each other, R 6 and R 7 are a hydrogen atom, an oxygen atom, a sulfur atom, a halogen atom, or an organic group having 1 to 20 carbon atoms, and can be the same as or different from each other. The organic group having 1 to 20 carbon atoms can contain at least one kind of atom selected from the group consisting of an oxygen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a nitrogen atom, a sulfur atom, a phosphorus atom, and a boron atom, and in the case where a plurality of the organic groups having 1 to 20 carbon atoms exist, the plurality of the organic groups can be bonded to each other to form a ring, k is an integer of 0 to 3, and in the case where k is an integer of 2 or more, a plurality of R 5 can be the same as or different from each other, p is an integer of 1 to 10, and in the case where p is an integer of 2 or more, a plurality of R 6 and R 7 can be the same as or different from each other, q is an integer of 0 to 3, and in the case where q is an integer of 2 or more, a plurality of R 8 can be the same as or different from each other.

[0109] In the compound represented by the general formula (III), in the case where R 5 or R 8In the case of halogen atoms, examples include fluorine atoms, chlorine atoms, bromine atoms or iodine atoms, with fluorine atoms, chlorine atoms or bromine atoms being preferred.

[0110] Additionally, in R 5 or R 8 When the organic group has 1 to 20 carbon atoms, examples include methyl, ethyl, isopropyl, isobutyl, n-propyl, n-butyl, tert-butyl, hexyl, octyl, cyclopentyl, cyclohexyl, and phenyl, with methyl and ethyl being preferred.

[0111] In compounds represented by general formula (III), when multiple organic groups having 1 to 20 carbon atoms are present, these multiple organic groups can bond together to form a ring. In this case, examples of multiple organic groups constituting the ring include (1) R. 5 (for cases where k is 2 or higher), (2)R 8 (for cases where q is 2 or more), (3)R 6 (for cases where p is 2 or more), (4)R 7 (for cases where p is 2 or more), (5)R 5 With R 6 (6)R 5 With R 7 (7)R 5 With R 8 (8)R 6 With R 7 (9)R 6 With R 8 (10)R 7 With R 8 The combination of (8)R is preferred. 6 With R 7 The combination of R is preferred 6 With R 7 They bond with each other to form fluorene rings, etc.

[0112] As the compound represented by General Formula (III), specifically, one or more selected from the group consisting of 2,2-diisobutyl-l,3-dimethoxypropane, 2-isopropyl-2-isobutyl-l,3-dimethoxypropane, 2-isopropyl-2-isopentyl-l,3-dimethoxypropane, 3,3-bis(methoxymethyl)-2,6-dimethylheptane, 9,9-bis(methoxymethyl)fluorene, and the like can be exemplified, preferably one or more selected from the group consisting of 2,2-diisobutyl-l,3-dimethoxypropane, 2-isopropyl-2-isopentyl-l,3-dimethoxypropane, 3,3-bis(methoxymethyl)-2,6-dimethylheptane, 9,9-bis(methoxymethyl)fluorene, more preferably one or more selected from the group consisting of 2-isopropyl-2-isobutyl-l,3-dimethoxypropane, 2-isopropyl-2-isopentyl-l,3-dimethoxypropane, 9,9-bis(methoxymethyl)fluorene.

[0113] In the compound represented by General Formula (III), k is an integer of 0 to 3, preferably an integer of 0 to 2, more preferably 0 or 1. In the case where k is an integer of 2 or more, a plurality of R 5 Each of R

[0114] In the compound represented by General Formula (III), p is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 6. In the case where p is an integer of 2 or more, a plurality of R 6 Each of R 7 Each of R

[0115] In the compound represented by General Formula (III), q is an integer of 0 to 3, preferably an integer of 0 to 2, more preferably 0 or 1. In the case where q is an integer of 2 or more, a plurality of R 8 Each of R

[0116] In the case where an ether carbonate is used as the internal electron-donating compound, as the ether carbonate, a compound represented by the following General Formula (IV) can be used:

[0117] R 9 -O-C(=O)-O-Z-OR 10 …(IV)

[0118] In Formula (IV), R 9 Each of R 10a straight-chain alkyl group having 1 to 20 carbon atoms, a branched alkyl group having 3 to 20 carbon atoms, a vinyl group, a straight-chain alkenyl group having 3 to 20 carbon atoms or a branched alkenyl group, a straight-chain halogen-substituted alkyl group having 1 to 20 carbon atoms, a branched halogen-substituted alkyl group having 3 to 20 carbon atoms, a straight-chain halogen-substituted alkenyl group having 2 to 20 carbon atoms, a branched halogen-substituted alkenyl group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a cycloalkenyl group having 3 to 20 carbon atoms, a halogen-substituted cycloalkyl group having 3 to 20 carbon atoms, a halogen-substituted cycloalkenyl group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 24 carbon atoms, a halogen-substituted aromatic hydrocarbon group having 6 to 24 carbon atoms, a nitrogen atom-containing hydrocarbon group having 2 to 24 carbon atoms in which the terminal is bonded to a carbon atom (except for the case where the terminal is bonded to a C=N group), an oxygen atom-containing hydrocarbon group having 2 to 24 carbon atoms in which the terminal is bonded to a carbon atom (except for the case where the terminal is bonded to a carbonyl group), or a phosphorus atom-containing hydrocarbon group having 2 to 24 carbon atoms in which the terminal is bonded to a carbon atom (except for the case where the terminal is bonded to a C=P group), R 9 and R 10 Z represents a bonding group which is bonded via a carbon atom or a carbon chain, and can be the same or different.

[0119] As specific examples of the compound represented by General Formula (IV), (2-ethoxyethyl)methyl carbonate, (2-ethoxyethyl)ethyl carbonate, and (2-ethoxyethyl)phenyl carbonate are particularly preferable.

[0120] In the production method of the Mg-containing particles according to the present application, in the case where the solid catalyst component includes a magnesium compound, a tetravalent titanium halide, and a contact reactant of an internal electron-donating compound, the contact and reaction of the magnesium compound, the tetravalent titanium halide, and the internal electron-donating compound can also be performed in the presence of a polysiloxane as the third component.

[0121] The polysiloxane refers to a polymer having a siloxane bond (-Si-O- bond) in the main chain, but is also collectively referred to as a silicone oil, and refers to a chain, partially hydrogenated, cyclic, or modified polysiloxane which is liquid or viscous at ordinary temperature and has a viscosity of 0.02 cm 2 / s to 100 cm 2 / s (2 centistokes to 10,000 centistokes), and more preferably 0.03 cm 2 / s to 5 cm 2 / s (3 centistokes to 500 centistokes).

[0122] As the chain polysiloxane, hexamethyldisiloxane, hexaethyldisiloxane, hexapropyldisiloxane, hexaphenyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1,3-dichlorotetramethyldisiloxane, 1,3-dibromotetramethyldisiloxane, chloromethylpentamethyldisiloxane, 1,3-bis(chloromethyl)tetramethyldisiloxane can be exemplified as disiloxanes, and dimethylpolysiloxane, methylphenylpolysiloxane can be exemplified as polysiloxanes other than disiloxanes, methylhydrogenpolysiloxane having a hydrogenation rate of 10 to 80% can be exemplified as partially hydrogenated polysiloxane, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, 2,4,6-trimethyltrisiloxane, 2,4,6,8-tetramethylcyclotetrasiloxane can be exemplified as cyclic polysiloxane, and higher fatty acid group-substituted dimethylsiloxane, epoxy group-substituted dimethylsiloxane, polyoxyalkylene group-substituted dimethylsiloxane can be exemplified as modified polysiloxane. Among them, decamethylcyclopentasiloxane and dimethylpolysiloxane are preferable, and decamethylcyclopentasiloxane is particularly preferable.

[0123] In the production method of the Mg-containing particles according to the present application, in the case where the Mg-containing particles having a magnesium compound as a main component are used as an olefin polymerization catalyst together with the above-mentioned solid catalyst component for olefin polymerization, an organic aluminum compound and an external electron donor compound as necessary,

[0124] As the above-mentioned organic aluminum compound, an organic aluminum compound represented by the following general formula (V) can be exemplified:

[0125] R 11 sAlQ 3-s …(V)

[0126] In the formula, R 11 is an alkyl group having 1 to 6 carbon atoms, Q is a hydrogen atom or a halogen atom, and s is a real number satisfying 0 < p < 3.

[0127] In the organic aluminum compound represented by the general formula (V), R 11 is an alkyl group having 1 to 6 carbon atoms, and specifically, a methyl group, an ethyl group, a n-propyl group, an i-propyl group, a n-butyl group, an i-butyl group, and the like can be exemplified.

[0128] In the organic aluminum compound represented by the above-mentioned general formula (V), Q represents a hydrogen atom or a halogen atom, and in the case where Q is a halogen atom, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom can be exemplified.

[0129] As the organic aluminum compound represented by the above-mentioned general formula (V), specifically, one or more selected from the group consisting of triethylaluminum, diethylaluminum chloride, triisobutylaluminum, diethylaluminum bromide, and diethylaluminum hydride can be exemplified, and triethylaluminum and triisobutylaluminum are suitable.

[0130] Further, as the external electron-donating compound, an organic compound containing an oxygen atom or a nitrogen atom can be exemplified, and specifically, an alcohol, a phenol, an ether, an ester, a ketone, an acyl halide, an aldehyde, an amine, an amide, a nitrile, an isocyanate, an organosilicon compound, and the like can be exemplified, among which an organosilicon compound having a Si-O-C bond and the like can be exemplified.

[0131] Among the external electron-donating compounds, ethyl benzoate, ethyl p-methoxybenzoate, ethyl p-ethoxybenzoate, methyl p-methylbenzoate, ethyl p-methylbenzoate, methyl anisate, ethyl anisate, and the like esters, 1,3-diethers, organosilicon compounds containing a Si-O-C bond, and particularly organosilicon compounds having a Si-O-C bond are preferable.

[0132] The content ratio of the solid catalyst component, the organoaluminum compound, and the external electron-donating compound constituting the catalyst for the polymerization of an olefin is not particularly limited, and with respect to 1 mole of titanium atoms in the solid catalyst component, the organoaluminum compound is preferably 1 mole to 2000 moles, and more preferably 50 moles to 1000 moles. Further, with respect to 1 mole of the organoaluminum compound, the external electron-donating compound is preferably 0.001 mole to 10 moles, more preferably 0.002 moles to 2 moles, and further preferably 0.002 moles to 0.5 moles.

[0133] In the method for producing the Mg-containing particles according to the present application, the unclassified Mg-containing particles subjected to the dissociation treatment and the classification treatment and the Mg-containing particles have a particle diameter of 1 μm to 200 μm, preferably 5 μm to 180 μm, and more preferably 9 μm to 160 μm.

[0134] Further, in the method for producing the Mg-containing particles according to the present application, the unclassified Mg-containing particles subjected to the dissociation treatment and the classification treatment and the Mg-containing particles have an average particle diameter (D 50 ) of 5 μm to 100 μm, more preferably 7 μm to 80 μm, and further preferably 10 μm to 60 μm.

[0135] In the present application, the particle diameter of the unclassified Mg-containing particles and the Mg-containing particles means a value measured by a laser scattering / diffraction method, and further, the average particle diameter (D 50 ) of the unclassified Mg-containing particles means a particle diameter at 50% in terms of cumulative particle size measured by a laser scattering / diffraction method.

[0136] In the method for producing the Mg-containing particles according to the present application, the unclassified Mg-containing particles and the Mg-containing particles have a particle size distribution index (SPAN) represented by the following formula (ii) of 0.5 to 5.0, more preferably 0.5 to 4.0, and further preferably 0.5 to 3.0.

[0137] Span = (D 90 -D 10 ) / D 50 …(ii)

[0138] D 10 , D 50 , and D 90 each refer to a particle size of 10%, a particle size of 50%, and a particle size of 90% by volume, respectively, as measured using the aforementioned measuring machine.

[0139] Note that, in the present specification, the average particle size (D 50 ) and the particle size distribution refer to values obtained using a laser diffraction type particle size distribution measuring device (Mastersizer 3000 manufactured by Spectris (K.K.),).

[0140] Further, the attrition durability A (%) of the unclassified Mg-containing particles represented by the following formula (1) is 85% or less, suitably 60% to 85%, more suitably 65% to 80%, and further suitably 70% to 75%.

[0141] Attrition durability A = (Z ÷ Y) x 100 … (1)

[0142] In the formula, Y represents the average particle size D 50 (μm) measured automatically in a dry manner at a blow pressure of 0.4 bar using a laser diffraction type particle size distribution measuring device, and Z represents the average particle size D 50 (μm) measured automatically in a dry manner at a blow pressure of 1.0 bar using the laser diffraction type particle size distribution measuring device.

[0143] In the manufacturing method of the Mg-containing particles of the present application, even in the case where the porous body particles which are weak and fragile in terms of particle strength, i.e., the unclassified Mg-containing particles, i.e., the particles which are generally difficult to classify and for which the attrition durability A is 90% or less, are classified, the content of the fine coarse powder particles such as fine powder particles and coarse powder particles can be reduced, and particle breakage can be prevented, and classified particles having a narrow particle size distribution and also a good particle shape can be obtained.

[0144] Note that, in the present specification, the attrition durability A refers to a value obtained using a laser diffraction type particle size distribution measuring device (Mastersizer 3000 manufactured by Spectris (K.K.),) and a dry-type dispersion unit for dry powder dispersion (Aero S manufactured by Spectris (K.K.)).

[0145] [Manufacturing method of Mg-containing particles]

[0146] [Preparation step]

[0147] In the production method of the Mg-containing particles according to the present application, the production step of producing the unclassified Mg-containing particles will be described. Note that the constitution of the unclassified Mg-containing particles obtained in the production step is as described above, and thus the description thereof will be omitted.

[0148] In the production method of the Mg-containing particles according to the present application, it is appropriate that the magnesium compound constituting the unclassified Mg-containing particles is produced using an alkylmagnesium as a raw material.

[0149] For example, the method of producing a dialkylmagnesium in a spherical shape is exemplified in, for example, Japanese Patent Application Publication No. S58-4132, Japanese Patent Application Publication No. S62-51633, Japanese Patent Application Publication No. H3-74341, Japanese Patent Application Publication No. H4-368391, Japanese Patent Application Publication No. H8-73388, and the like.

[0150] In the production method of the Mg-containing particles according to the present application, the obtained dialkylmagnesium can be classified by the method described in the following classification step.

[0151] In the production method of the Mg-containing particles according to the present application, as the solid catalyst component for the polymerization of an olefin, which contains titanium, a halogen, and one or more internal electron donors together with the above-described magnesium compound, the contact reactant of an alkylmagnesium, a tetravalent titanium halide, and an internal electron-donating compound can also be classified by the method described in the following classification step.

[0152] The process of contacting and reacting the above-described magnesium compound, the tetravalent titanium halide, the internal electron-donating compound (and the polysiloxane as the case can be) is preferably performed in the presence of a non-reactive organic solvent such as toluene or hexane.

[0153] As the above-described non-reactive organic solvent, a non-reactive organic solvent that is liquid at normal temperature (20°C) and has a boiling point of 50°C to 150°C is preferred, and a aromatic hydrocarbon compound or a saturated hydrocarbon compound that is liquid at normal temperature and has a boiling point of 50°C to 150°C is more preferred.

[0154] The temperature at the time of the above-described reaction is preferably 0°C to 130°C, more preferably 40°C to 130°C, further preferably 30°C to 120°C, and more further preferably 80°C to 120°C. In addition, the reaction time is preferably 1 minute or more, more preferably 10 minutes or more, further preferably 30 minutes to 6 hours, more further preferably 30 minutes to 5 hours, and more further preferably 1 hour to 4 hours.

[0155] When the magnesium compound, the tetravalent titanium halide, and the internal electron-donating compound are contacted and reacted, the amount of the tetravalent titanium halide is preferably 0.5 to 100 moles, more preferably 1 to 50 moles, and further preferably 1 to 10 moles, relative to 1 mole of the magnesium compound.

[0156] The contacting of the components is preferably performed in a container equipped with a stirrer, under an atmosphere of an inactive gas, and with removal of moisture and the like, while stirring.

[0157] After the above reaction, the reaction product is preferably left to stand, and the supernatant is appropriately removed to produce a wet state (slurry state), or further dried by hot air drying or the like, and on this basis, a washing treatment is performed.

[0158] The washing treatment is generally performed using a washing liquid.

[0159] As the washing liquid, the same substances as the above inactive organic solvents can be cited, and by using the above washing liquid, the by-products and impurities can be easily dissolved and removed from the reaction product.

[0160] By performing the washing treatment after the contacting and reaction of the above components, the unreacted raw material components and the impurities of the reaction by-products (titanium alkoxide halide, titanium tetrachloride-carboxylic acid complex, and the like) remaining in the reaction product can be removed.

[0161] The reaction product of the contacting of the above components is generally in a suspension state, and by leaving the suspension state to stand, removing the supernatant, and producing a wet state (slurry state), or further drying by hot air drying or the like, a solid catalyst component can be obtained.

[0162] In the above solid catalyst component, the content of magnesium atoms is preferably 10 to 70 mass%, more preferably 10 to 50 mass%, and further preferably 15 to 40 mass%, and particularly preferably 15 to 25 mass%.

[0163] In the above solid catalyst component, the content of titanium atoms is preferably 0.5 to 8.0 mass%, more preferably 0.5 to 5.0 mass%, and further preferably 0.5 to 3.0 mass%.

[0164] In the above solid catalyst component, the content of halogen atoms is preferably 20 to 88 mass%, more preferably 30 to 85 mass%, and further preferably 40 to 80 mass%, and more further preferably 45 to 75 mass%.

[0165] The content of the internal electron-donating compound in the solid catalyst component is preferably from 1.5 to 30.0% by mass, more preferably from 3.0 to 25.0% by mass, and even more preferably from 6.0 to 25.0% by mass.

[0166] In the present application, the content of magnesium atoms in the solid catalyst component is a value determined by EDTA titration method by dissolving the solid catalyst component with a hydrochloric acid solution and titrating with an EDTA solution.

[0167] In the present application, the content of titanium atoms in the solid catalyst component is a value determined according to the method (oxidation-reduction titration) described in JIS 8311-1997 "Method for determination of titanium in titanium ores".

[0168] In the present application, the content of magnesium atoms in the solid catalyst component is a value determined by EDTA titration method by dissolving the solid catalyst component with a hydrochloric acid solution and titrating with an EDTA solution.

[0169] In the present application, the content of halogen atoms in the solid catalyst component is a value determined by silver nitrate titration method, which is a method of titrating halogen atoms with a silver nitrate standard solution after preparing an aqueous solution by treating the solid catalyst component with a mixed solution of sulfuric acid and pure water, and separating a predetermined amount.

[0170] In the present application, the content of the internal electron-donating compound in the solid catalyst component is a result obtained using a standard curve based on a previously known concentration when determined using a gas chromatograph (Shimadzu Corporation, GC-14B) under the following conditions.

[0171] <Measurement conditions of gas chromatograph>

[0172] Column: packed column (φ 2.6 x 2.1 m, Silicone SE-30 10%, Chromosorb WAW DMCS 80 / 100, GL Sciences, Inc.)

[0173] Detector: FID (Flame Ionization Detector)

[0174] Carrier gas: helium, flow rate 40 ml / min

[0175] Measurement temperature: vaporizing chamber 280°C, column 225°C, detector 280°C, or vaporizing chamber 265°C, column 180°C, detector 265°C

[0176] In the production method of the Mg-containing particles according to the present application, the obtained solid catalyst component for olefin polymerization can be fractionated by the method shown in the fractionation step described later.

[0177] In the production method of the Mg-containing particles according to the present application, in the case where the un-fractionated Mg-containing particles having a magnesium compound as a main component are used as an olefin polymerization catalyst together with the above-mentioned solid catalyst component for olefin polymerization, the olefin polymerization catalyst can be produced by contacting (a) the solid catalyst component, (β) the organoaluminum compound, and (γ) the external electron donor using a publicly known method.

[0178] The order of contacting the above-mentioned components is arbitrary, and for example, the following contacting orders can be exemplified.

[0179] (i) (a) the solid catalyst component → (γ) the external electron donor → (β) the organoaluminum compound

[0180] (ii) (β) the organoaluminum compound → (γ) the external electron donor → (a) the solid catalyst component

[0181] (iii) (γ) the external electron donor → (a) the solid catalyst component → (β) the organoaluminum compound

[0182] (iv) (γ) the external electron donor → (β) the organoaluminum compound → (a) the solid catalyst component

[0183] Among the above-mentioned contacting examples (i) to (iv), contacting example (ii) is preferred.

[0184] Note that, in the above-mentioned contacting examples (i) to (iv), "→" means the order of contacting, and for example, "(a) the solid catalyst component for olefin polymerization → (β) the organoaluminum compound → (γ) the external electron donor" means that (β) the organoaluminum compound is added to (a) the solid catalyst component and contacted, and then (γ) the external electron donor is added and contacted.

[0185] The above-mentioned olefin polymerization catalyst can be one in which the solid catalyst component, the organoaluminum compound, and the external electron donor are contacted in the absence of an olefin, or one in which they are contacted in the presence of an olefin (in a polymerization system).

[0186] In order to prevent the deterioration of the solid catalyst component and the olefin polymerization catalyst after production, the contacting of the above-mentioned solid catalyst component, the organoaluminum compound, and the external electron donor is preferably performed in an atmosphere of an inactive gas such as argon or nitrogen, or in an atmosphere of a monomer such as propylene.

[0187] Further, in view of the easiness of the operation, it is also preferable to be performed in the presence of a dispersion medium such as a non-reactive solvent.

[0188] The contact temperature at the time of contacting the above components is preferably -10°C to 100°C, more preferably 0°C to 90°C, and further preferably 20°C to 80°C. The contact time is preferably 1 minute to 10 hours, more preferably 10 minutes to 5 hours, and further preferably 30 minutes to 2 hours.

[0189] By setting the contact temperature and the contact time to the above ranges, the polymerization activity of the olefin polymerization catalyst, the stereoregularity of the obtained polymer are easily improved, and as a result, the mechanical properties of the obtained olefin polymer are easily improved.

[0190] [Processing step]

[0191] Next, in the manufacturing method of the Mg-containing particles of the present application, the processing step of processing the unclassified Mg-containing particles will be described. In the processing step, the unclassified Mg-containing particles including the particles of which the aggregation is released and the particles in the aggregated state are processed, thereby dissociating the aggregated state of the aggregated Mg-containing particles, and further classifying the unclassified Mg-containing particles of which the aggregation is released, to obtain the Mg-containing particles. That is, in the processing step, the dissociation processing and the classification processing of the unclassified Mg-containing particles are performed to obtain the Mg-containing particles, and remove the particles other than the Mg-containing particles, i.e., the fine powder. In the processing step, the unclassified Mg-containing particles are subjected to the classification processing using a centrifugal airflow classification device having a rotating body with a diameter of 200 mm to 1000 mm. Note that, a pretreatment step can be performed before the processing step. By providing the pretreatment step, the removal of the coarse powder particles such as the agglomerated particles and the impurities such as the iron powder from the unclassified Mg-containing particles can be performed by means of sieving or the like.

[0192] Here, the fine powder (fine powder particles, particles other than the Mg-containing particles) in the present specification means particles that can generate a "fine powder-like polymer (also referred to as a fine powder polymer)" of a predetermined particle diameter in the case of being supplied to the polymerization of the olefins. In the polymerization of the olefins, if such a fine powder polymer increases, it hinders the continuation of the uniform polymerization reaction, and becomes a cause of process troubles such as the clogging of the piping at the time of transporting the polymer, and thus is not preferable. Further, it is not preferable to have an influence of increasing the defective products and the like on the molding processing of the polymer, and thus it is desirable to reduce the fine powder polymer. Therefore, in the manufacturing method of the Mg-containing particles of the present application, in the above processing step, the dissociation processing and the classification processing of the unclassified Mg-containing particles are performed to remove the particles other than the Mg-containing particles, i.e., the fine powder.

[0193] In the present specification, the fine powder (fine powder particles) that becomes the object to be removed by the classification processing can be determined according to the average particle diameter (D 50), the polymerization activity is calculated by the following formula (A).

[0194] The particle size of the fine powder = (average particle size of the polymer) / (polymerization activity) 3 √(polymerization activity) (A)

[0195] For example, in the case of a polymer having an average particle size (D 50 ) of 75 (μm) and a polymerization activity of 40,000 to 65,000 (g-pp / g-cat), a solid catalyst (fine powder) of 75 ÷ (34.2 to 39.6) = 1.9 to 2.9 (μm) can become a "fine-powdered polymer". Thus, the fine powder (fine powder particles) that becomes the object to be removed in the classification treatment in this case refers to particles of substantially less than 5 (μm).

[0196] Note that, in the present specification, the average particle size (D 50 ) of the polymer formed by supplying the Mg-containing particles (product) to the polymerization of an olefin-based monomer is 100 μm to 5,000 μm, and the polymerization activity of the polymer is 8,000 to 150,000 (g-pp / g-cat). Thus, the particle size of the fine powder (fine powder particles) that becomes the object to be removed by the classification treatment in the present specification is 0.1 μm to 100.0 μm.

[0197] Here, the rotating body refers to a disc-shaped classification rotor provided in a centrifugal airflow classification device.

[0198] The disc-shaped classification rotor has a diameter of 200 mm to 1,000 mm, suitably 300 mm to 800 mm, and more suitably 300 mm to 700 mm.

[0199] In the method for producing Mg-containing particles according to the present application, by setting the diameter of the disc-shaped classification rotor that constitutes the centrifugal airflow classification device within the above range, fine-coarse powder particles such as fine powder particles and coarse powder particles can be appropriately removed without damaging the unclassified Mg-containing particles, and the rotational speed and the air volume that enable the recovery of Mg-containing particles having a narrow particle size distribution and also a good particle shape can be easily achieved.

[0200] In the manufacturing method of the Mg-containing particles according to the present application, as the centrifugal airflow classifying device, as long as it is a device that classifies the powder in a dry manner by balancing the centrifugal force of the rotating disk-shaped classifying rotor with the centripetal force of the gas suction, there is no particular limitation, and a forced vortex centrifugal classifying device or a semi-free vortex centrifugal classifying device, etc. is preferably used, the forced vortex centrifugal classifying device has a rotating body inside the device, and the centrifugal force is applied to the particles by the rotating force thereof, and the resistance is applied to the particles by the inward airflow passing through the inside of the device; the semi-free vortex centrifugal classifying device does not have a rotating body inside the device, and a guide blade, etc. is provided to form a rotating airflow, the centrifugal force is applied to the particles by the rotating action, and the resistance is applied to the particles by the rotating airflow itself.

[0201] In the manufacturing method of the Mg-containing particles according to the present application, the rotational speed when the unclassified Mg-containing particles are airflow classified using the centrifugal airflow classifying device having the disk-shaped classifying rotor is 3000 rpm (revolutions / minute) or less, more appropriately 100 rpm to 3000 rpm, and further appropriately 500 rpm to 2500 rpm.

[0202] In the manufacturing method of the Mg-containing particles according to the present application, when the unclassified Mg-containing particles are airflow classified using the centrifugal airflow classifying device having the disk-shaped classifying rotor, the total airflow amount (total airflow amount) of the airflow amount in which the unclassified Mg-containing particles are supplied to the centrifugal airflow classifying device and the airflow amount in which the particles are fed to the inside of the disk-shaped classifying rotor is 1 m 3 / minute to 50 m 3 / minute, and appropriately 5 m 3 / minute to 40 m 3 / minute, and more appropriately 5 m 3 / minute to 30 m 3 / minute.

[0203] In the manufacturing method of the Mg-containing particles according to the present application, when the unclassified Mg-containing particles are airflow classified using the centrifugal airflow classifying device having the disk-shaped classifying rotor, the airflow amount (circulation airflow amount) in which the particles are fed to the inside of the disk-shaped classifying rotor is 1 m 3 / minute to 50 m 3 / minute, and appropriately 1 m 3 / minute to 35 m 3 / minute, and more appropriately 5 m 3 / minute to 20 m 3 / minute.

[0204] In the method for producing the Mg-containing particles according to the present application, the circumferential velocity of the disc-shaped classification rotor (rotating body) at the time of classification is preferably in the range of 2 m / sec to 130 m / sec, more preferably in the range of 6 m / sec to 110 m / sec, and further preferably in the range of 9 m / sec to 90 m / sec.

[0205] Note that the circumferential velocity of the disc-shaped classification rotor (rotating body) is a value calculated based on the diameter L (mm) of the classification rotor and the rotational speed S (rpm) of the classification rotor (rotating body) by the following formula (2).

[0206] Circumferential velocity (m / sec) of disc-shaped classification rotor (rotating body) = L (mm) x π x S (turns / min) ÷ 1000 ÷ 60 (2)

[0207] In the method for producing the Mg-containing particles according to the present application, the classification time is preferably in the range of 20 minutes to 900 minutes, more preferably in the range of 40 minutes to 800 minutes, and further preferably in the range of 60 minutes to 600 minutes.

[0208] In the method for producing the Mg-containing particles according to the present application, there is provided a step of reducing the flow rate of the unclassified Mg-containing particles flowing inside a flow path defined by the top surface of the classification rotor (rotating body) and connecting the inlet port and the classification chamber and supplying the unclassified Mg-containing particles to the classification chamber. Thus, the impact energy at the time of collision of the Mg-containing particles with the inner surface of the housing or the like is reduced, and the yield of the product is improved. At this time, as the amount of reduction of the flow rate of the Mg-containing particles, it is preferable to be set as follows.

[0209] That is, in the method for producing the Mg-containing particles according to the present application, it is preferable that, in the step of supplying the unclassified Mg-containing particles to the classification chamber, the average flow rate of the unclassified Mg-containing particles in the vertical direction cross section of the inlet of the classification chamber is reduced to half or less of the average flow rate of the unclassified Mg-containing particles at the upstream end of the flow path.

[0210] Further, in the method for producing Mg-containing particles according to the present application, in the step of supplying the unclassified Mg-containing particles to the classification chamber, the average flow rate of the unclassified Mg-containing particles in the vertical cross section at the substantially middle position of the radius of the classification rotor is preferably 2 / 3 or less of the average flow rate of the unclassified Mg-containing particles at the upstream end of the flow path. Further, in the method for producing Mg-containing particles according to the present application, the average flow rate of the Mg-containing particles in the vertical cross section of the inlet of the classification chamber is preferably 15 m / s or less. Note that, in the present specification, the "substantially middle position" of the radius of the top surface of the classification rotor (rotating body) refers to a position including the middle position of the radius of the top surface of the classification rotor and any position within a range of a length corresponding to 10% of the radius of the top surface of the classification rotor from the middle position. When the length of the radius of the classification rotor (rotating body) is set to X, the distance Y from the center of the top surface of the classification rotor (rotating body) to the substantially middle position can be represented by the following equation, for example.

[0211] [Num. 1]

[0212]

[0213] In the method for producing Mg-containing particles according to the present application, as the classification medium at the time of classification using the gas flow classification device having the above-described classification rotor, a dry gas having a moisture content of 20 mass ppm or less is preferably used, and in the case where the unclassified Mg-containing particles are a solid catalyst component for olefin polymerization, in order not to deactivate the active titanium component and the like supported on the magnesium compound particles, an inactive gas such as argon or nitrogen is preferably used.

[0214] In the method for producing Mg-containing particles according to the present application, the supply amount of the unclassified Mg-containing particles is preferably 1 kg / hour to 60 kg / hour, more preferably 3 kg / hour to 50 kg / hour, and further preferably 5 kg / hour to 40 kg / hour.

[0215] In the method for producing Mg-containing particles according to the present application, the particle size distribution index (SPAN) defined by the above-described equation (ii) of the obtained Mg-containing particles (classified particles) is preferably 1 or less, more preferably 0.9 or less, and further preferably 0.8 or less.

[0216] According to the present application, by using a centrifugal gas flow classification device having a rotating body with a diameter in a specific range, Mg-containing particles containing magnesium as a main component and having an average particle diameter D 50The use of the unclassified Mg-containing particles having a particle size (μm) of 5 μm to 100 μm in air classification enables removal of fine powder particles, coarse powder particles, and the like, and also enables moderate separation of coarse powder particles having low particle strength, thereby inhibiting the destruction of particles having a desired particle size and increasing the proportion thereof, and thus enables easy production of classified particles having a desired particle size and a narrow particle size distribution at a high yield.

[0217] <Method for producing olefin-based polymer>

[0218] Next, a method for producing an olefin-based polymer using the Mg-containing particles produced by the method for producing Mg-containing particles according to the present application will be described.

[0219] The method for producing an olefin-based polymer is characterized in that, in the case where the unclassified Mg-containing particles in the method for producing Mg-containing particles according to the present application are a solid catalyst component for olefin polymerization or an olefin polymerization catalyst, the obtained classified particles are used to polymerize an olefin.

[0220] Specifically, in the case where the unclassified Mg-containing particles in the method for producing Mg-containing particles according to the present application are a solid catalyst component for olefin polymerization, the obtained solid catalyst component is used to form an olefin polymerization catalyst, and the polymerization of an olefin is performed in the presence of the olefin polymerization catalyst. In addition, in the case where the unclassified Mg-containing particles in the method for producing Mg-containing particles according to the present application are an olefin polymerization catalyst, the polymerization of an olefin is performed in the presence of the obtained olefin polymerization catalyst.

[0221] In the method for producing an olefin-based polymer, as the olefin, one or more selected from the group consisting of ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, vinylcyclohexane, and the like can be exemplified, and propylene or 1-butene is preferable, and propylene is more preferable.

[0222] In the case of polymerizing propylene, copolymerization with other olefins can be performed, and as the copolymerization of propylene with other olefins, random copolymerization in which propylene and a small amount of ethylene are used as comonomers and polymerization is performed in one stage, and so-called propylene-ethylene block copolymerization in which homopolymerization of propylene is performed in a first stage (first polymerization tank) and copolymerization of propylene with other α-olefins such as ethylene is performed in a second stage (second polymerization tank) or more stages (multistage polymerization tank) are representative, and block copolymerization of propylene with other α-olefins is preferable.

[0223] The block copolymer obtained by block copolymerization refers to a polymer containing two or more kinds of monomer components continuously and variably changed in chain segments, and refers to a polymer chain (chain segment) in which two or more kinds of polymers differing in primary structure such as monomer species, comonomer species, comonomer composition, comonomer content, comonomer arrangement, and stereoregularity are connected in one molecular chain.

[0224] As the olefin to be copolymerized, an α-olefin having 2 to 20 carbon atoms (excluding propylene having 3 carbon atoms) is preferred, and specifically, ethylene, 1-butene, 1-pentene, 4-methyl-l-pentene, vinylcyclohexane, and the like can be mentioned, and one or more kinds thereof can be used in combination. As the olefin to be copolymerized, ethylene or 1-butene is suitable, and ethylene is particularly suitable.

[0225] In the method for producing an olefin polymer, the polymerization of the olefin can be performed in the presence or absence of an organic solvent.

[0226] Further, the olefin to be polymerized can be used in any state of gas or liquid.

[0227] The polymerization of the olefin is performed, for example, in a reaction furnace such as an autoclave, in the presence of the olefin polymerization catalyst, under heating and pressurization.

[0228] In the method for producing an olefin polymer, the polymerization temperature is usually 200°C or lower, preferably 100°C or lower, more preferably 60°C to 100°C from the viewpoint of improving the activity and stereoregularity, further preferably 70°C to 90°C, and more further preferably 75°C to 80°C. In the method for producing an olefin polymer of the present application, the polymerization pressure is preferably 10 MPa or lower, and more preferably 5 MPa or lower.

[0229] In the method for producing an olefin polymer, even in the case where homopolymerization is performed at a higher temperature within the above-mentioned polymerization temperature range, the hydrogen activity is excellent, and a polymer having a high stereoregularity and MFR can be produced at a high productivity, and even in the case where copolymerization is performed at a high temperature, excellent hydrogen activity and copolymerization activity can be achieved, and a copolymer having excellent impact resistance can be produced.

[0230] Further, either a continuous polymerization method or a batch polymerization method can be used. Furthermore, the polymerization reaction can be performed in one stage, or in two or more stages.

[0231] In the method for producing an olefin polymer, the block copolymerization reaction of propylene with another α-olefin can be generally performed as follows: in the presence of the olefin polymerization catalyst of the present application, propylene is contacted alone or propylene is contacted with a small amount of an α-olefin (ethylene or the like) in the former stage, and then propylene is contacted with an α-olefin (ethylene or the like) in the latter stage. Note that the polymerization reaction in the former stage can be repeated a plurality of times, or the polymerization reaction in the latter stage can be repeated a plurality of times, and the reaction can be performed by a multistage reaction.

[0232] As to the block copolymerization of propylene and other α-olefins, specifically, the polymerization is carried out in the former stage in a manner that the proportion of the polypropylene fraction (in the final copolymer) becomes 20 to 90% by weight, and then, in the latter stage, propylene and ethylene or other α-olefins are introduced to polymerize in a manner that the proportion of the rubber fraction such as ethylene-propylene rubber (EPR) (in the final copolymer) becomes 10 to 80% by weight.

[0233] The polymerization temperature in the former and latter stages is preferably 200°C or lower, more preferably 100°C or lower, and further preferably 75 to 80°C, and the polymerization pressure is preferably 10 MPa or lower, and more preferably 5 MPa or lower.

[0234] In the above copolymerization, either of a continuous polymerization method and a batch polymerization method can be employed, and the polymerization can be carried out in one stage or two or more stages.

[0235] Further, the polymerization time (residence time in the reactor) is preferably 1 minute to 5 hours in each of the polymerization stages in the former or latter stages, or in the case of continuous polymerization.

[0236] As the polymerization method, there are a slurry polymerization method using a non-active hydrocarbon compound such as cyclohexane or heptane as a solvent, a bulk polymerization method using a solvent such as liquefied propylene, and a gas phase polymerization method using substantially no solvent, and the bulk polymerization method or the gas phase polymerization method is suitable, and from the viewpoint of suppressing the elution of EPR from the PP particles, the reaction in the latter stage is usually preferably a gas phase polymerization reaction.

[0237] In the method for producing an olefin-based polymer, a part or all of the components of the catalyst for olefin-based polymerization can be contacted with the olefin-based polymerization target olefin-based compound to perform prepolymerization (hereinafter, appropriately referred to as preliminary polymerization).

[0238] The order of contacting the components of the catalyst for olefin-based polymerization and the olefin-based compound is arbitrary, and it is preferable to first load the organic aluminum compound in the preliminary polymerization system set to an atmosphere of non-active gas or olefin gas, and then contact the solid catalyst component and the olefin-based compound such as propylene one or more times. Alternatively, it is preferable to first load the organic aluminum compound in the preliminary polymerization system set to an atmosphere of non-active gas or olefin gas, then contact the external electron-donating compound as necessary, and further contact the solid catalyst component and the olefin-based compound such as propylene one or more times.

[0239] In the preliminary polymerization, the same olefin-based compound as in the main polymerization, or a monomer such as styrene can be used, and the preliminary polymerization conditions are the same as the above polymerization conditions.

[0240] By carrying out the above-mentioned prepolymerization, the catalytic activity is improved, and it is easier to further improve the stereoregularity and particulate properties of the obtained polymer.

[0241] According to the manufacturing method of olefin polymers, it is appropriate for the particle size distribution index (SPAN) of the obtained olefin polymer, as specified by the above formula (ii), to be 1 or less, more appropriate to be 0.9 or less, and even more appropriate to be 0.8 or less.

[0242] By using the Mg-containing particles obtained by the manufacturing method of the present invention, it is possible to provide a method for manufacturing olefin polymers with narrow particle size distribution that reduces the content of fine and coarse particles in polymer particles.

[0243] [Implementation Method of Mg Particle Classification Device]

[0244] The following is for reference Figs. 1 to 4 The Mg-containing particle classifier 11 of the embodiment will be described. The Mg-containing particle classifier 11 is an example of a centrifugal airflow classifier.

[0245] like Fig. 1 As shown, the Mg-containing particle grading device 11 includes a housing 12 covering the whole, a grading rotor 13 and a balancing rotor 14 disposed within the housing 12, a rotating shaft 15 supporting and rotating the grading rotor 13 and the balancing rotor 14, a motor (not shown) for rotating and driving the rotating shaft 15, and a flow path 17 defining the outer edge of the housing 12 by the inner surface 19 and the top surface 16 of the grading rotor 13.

[0246] In this specification, housing 12 refers to an outer shell having a generally cylindrical overall shape. Housing 12 is formed in the shape of a container constituting the outer shell of the Mg-containing particle grading apparatus 11, and surrounds a portion of the grading rotor 13, the balancing rotor 14, and the rotating shaft 15. Housing 12 includes a cylindrical portion 30, an inlet 18 located at the top of the cylindrical portion 30 for receiving ungraded Mg-containing particles 20, an outlet 21 located on the upper part of the peripheral portion for receiving Mg-containing particles 24 as the graded product, a spiral shell 22 located on the lower part of the peripheral portion, and an air inlet 23 located on the peripheral portion between the outlet 21 and the spiral shell 22. Ungraded Mg-containing particles 20 are introduced into the Mg-containing particle grading apparatus 11 along with air through the inlet 18. The top of the inlet 18 is formed into a flange shape and connected to an ungraded Mg-containing particle supply device (not shown) for supplying the ungraded Mg-containing particles 20. The spiral shell 22 is connected to the collection device and the fan, and is able to remove the fine powder 24a along with the air.

[0247] A rotary shaft 15 is provided at the center of the housing 12. The rotary shaft 15 is rotatably supported by a bearing 25, and a pulley 26 is attached to the lower end. The rotary shaft 15 is rotationally driven by a motor via the pulley 26. The classification rotor 13 and the balance rotor 14 are configured to be rotatable (self-rotatable) in the horizontal plane.

[0248] The classification rotor 13 is an example of a rotary body that rotates in the horizontal plane. The classification rotor 13 has a top surface 16, a first cavity portion 27 provided inside and communicating from the outer edge portion to the lower portion of the center portion, a plurality of classification vanes 28 provided at the outer edge portion of the first cavity portion 27 at equal intervals, a plurality of classification chambers 31 provided in the space portions between the classification vanes 28, a plurality of openings 32 provided in the top surface 16 and formed at positions corresponding to substantially the center in the radial direction of the classification vanes 28, and a plurality of auxiliary vanes 33 provided at equal intervals on the lower surface opposite to the classification vanes 28. The diameters of the classification rotor 13 and the balance rotor 14 are, for example, 200 mm to 1000 mm, preferably 300 mm to 800 mm, and more preferably 300 mm to 700 mm. The plurality of classification vanes 28 each include, for example, an inner classification vane 28A and an outer classification vane 28B.

[0249] The top surface 16 is formed in a substantially flat shape. The top surface 16 has a flat portion 16A and a conical portion 16B provided at the center portion of the flat portion 16A in a conical frustum shape. A pin that prevents the classification rotor 13 and the balance rotor 14 from falling off the rotary shaft 15 is housed in the inside of the conical portion 16B.

[0250] The plurality of classification vanes 28 each extend radially of the classification rotor 13. The plurality of openings 32 are each formed in a substantially annular shape along the outer edge of the top surface 16, and can cause the powder to fall toward the classification chambers 31.

[0251] The auxiliary vanes 33 impart a flow in the direction of rotation to the air when the classification rotor 13 rotates, and can introduce the air into the classification chambers 31 in a state of rotation.

[0252] The Mg-containing particle classification device 11 has an empty portion 34 between the outer edge portion of the classification rotor 13 and the housing 12. The take-out port 21 is formed to communicate with the empty portion 34.

[0253] The counterweight rotor 14 has a shape symmetrical to the classification rotor 13 in the horizontal plane and has substantially the same weight as the classification rotor 13. The counterweight rotor 14 has substantially the same as the classification rotor 13 a second cavity portion 35 communicating from an outer edge portion thereof to above the center portion and a plurality of vanes 36 provided in the vicinity of the opening portion in the second cavity portion 35. The second cavity portion 35 is integrally fixed to the classification rotor 13 and the rotary shaft 15 in a manner of communicating to the first cavity portion 27 of the classification rotor 13 above the center portion. In the vicinity of the outlet of the second cavity portion 35 of the counterweight rotor 14, the spiral housing 22 is disposed in a manner of surrounding the same.

[0254] As shown in Fig. 2 , the flow path 17 is formed in a part of a path linking the throw-in port 18 and the classification chamber 31. The flow path 17 is a concept including the inner surface 19 of the housing 12 forming an outer edge thereof and the top surface 16 of the classification rotor 13, and a cavity portion therebetween for fluid to flow. As shown in Fig. 3 , Fig. 4 , the flow path 17 includes an upstream end portion 17A on the upstream side of the flow path 17, which is a gap provided between the lower inner surface of the cylindrical portion 30 forming the throw-in port 18 and the upper end portion of the tapered portion 16B, and an inlet 31A of the classification chamber provided on the downstream side of the flow path 17 and located at the boundary with the classification chamber 31. That is, the flow path 17 connects the upstream end portion 17A and the classification chamber 30. The upstream end portion 17A corresponds to the end portion on the upstream side of the flow path 17 in the flow direction of the unclassified Mg-containing particles 20, and corresponds to the inlet of the flow path 17. The cross-sectional area of the flow path 17 of the present embodiment is larger than that of the flow path 17 of the classification device 41 of the reference embodiment described later. In the present embodiment, the inner surface 19 of the housing 12 is disposed at a position apart from the top surface 16 of the classification rotor 13, compared to the classification device 41 of the reference embodiment.

[0255] The flow path 17 is formed in a space defined by the inner surface 19 of the housing 12 and the top surface 16 of the classification rotor 13, and is formed in a substantially disc shape expanding outwardly from the throw-in port 18. The housing 12 has a first portion 12A provided to the housing 12 at a position opposite to the flat portion 16A of the top surface 16, a second portion 12B provided to the housing 12 at a position opposite to the flat portion 16A of the top surface 16 and on the throw-in port 18 side (inner side) than the first portion 12A, and a third portion 12C provided to the housing 12 at a position opposite to the tapered portion 16B of the top surface 16. The first portion 12A is apart from the top surface 16 (flat portion 16A) by a first predetermined distance. The first predetermined distance is represented by a dimension d in Fig. 2 , for example, and is, for example, 6 mm to 15 mm, and further preferably 8 mm to 12 mm.

[0256] The second portion 12B departs from the top surface 16 (flat portion 16A) by a second predetermined distance that is greater than the first predetermined distance. The second predetermined distance is, for example, 11 mm to 16 mm, and is further preferably 12 mm to 15 mm. Fig. 2 The second portion 12B is formed so as to satisfy the relationship of dimension c > dimension d. The second predetermined distance is, for example, 11 mm to 16 mm, and is further preferably 12 mm to 15 mm.

[0257] The second portion 12B is inclined so as to depart from the top surface 16 as it approaches the center direction of the classification rotor 13 (as it approaches the throw-in port 18). The distance between the portion of the second portion 12B that is farthest from the top surface 16 and the top surface 16 (flat portion 16A) is represented by dimension b in Fig. 2

[0258] The third portion 12C is formed so as to be chamfered at the corners, so that no edges are present within the flow path 17 at positions opposite the tapered portion 16B. The third portion 12C is formed so as to be substantially parallel along the side surface of the tapered portion 16B. The distance between the third portion 12C and the side surface of the tapered portion 16B is represented by dimension a in Fig. 2

[0259] As described above, the flow path 17 is formed so as to have a relatively large cross-sectional area at portions corresponding to the third portion 12C and the second portion 12B. Therefore, according to the continuity equation of fluid mechanics, the average flow velocity of the unclassified Mg-containing particles 20 on the downstream side of the upstream end portion 17A in the flow path 17 can be made smaller than the average flow velocity of the unclassified Mg-containing particles 20 at the upstream end portion 17A inside the flow path 17.

[0260] More specifically, the flow path 17 can reduce the average flow velocity of the unclassified Mg-containing particles 20 at the inlet 31A of the classification chamber 31 to be less than half of the average flow velocity of the unclassified Mg-containing particles 20 in the upstream end portion 17A. In addition, the flow path can reduce the average flow velocity of the unclassified Mg-containing particles 20 at a substantially middle position of the radius of the classification rotor 13 (the top surface 16 of the classification rotor 13) to be less than two-thirds of the average flow velocity of the unclassified Mg-containing particles 20 at the upstream end portion 17A. Thus, the flow path 17 of the Mg-containing particle classification device 11 of the present embodiment can greatly reduce the flow velocity of the unclassified Mg-containing particles 20 in the first half portion (the second portion 12B and the third portion 12C). Furthermore, the flow path 17 can set the average flow velocity of the unclassified Mg-containing particles 20 at the inlet 31A of the classification chamber 31 to be, for example, 15 m / s or less.

[0261] ​​Further, the Mg-containing particle classifying device 11 is capable of removing fine powder particles (particles other than the Mg-containing particles) having a particle size of less than 5 μm, which are contained in the unclassified Mg-containing particles 20. The particle size (boundary point) of the particles removed as fine powder at the time of classification is in a range of 5 μm or more and less than the average particle size (D 50 ) of the unclassified Mg-containing particles 20, and can be appropriately adjusted by setting the size of the classification rotor 13, the rotational speed of the classification rotor 13, the size of the flow path 17, the size of the fan connected to the spiral housing 22, other conditions, within the above range. Thus, the Mg-containing particle classifying device 11 is capable of reliably removing the fine powder particles (for example, fine powder particles having a particle size of less than 5 μm) that are the removal target. Note that the particle size of the fine powder particles can be calculated by the above formula (A) and can be appropriately set within a range of 0.1 μm to 100.0 μm.

[0262] Next, the action of the Mg-containing particle classifying device 11 of the present embodiment and the manufacturing method of the Mg-containing particles will be described with reference to Figs. 1 to 4

[0263] The classification rotor 13 and the balance rotor 14 are rotated at a predetermined speed by the driving of the motor. The rotational speed of the classification rotor 13 is as described above in the classification process.

[0264] A negative pressure is generated inside the housing 12 by the fan connected to the spiral housing 22. Thus, as indicated by the arrows, air is drawn from the air introduction port 23, and the air flowing in by this drawing is converted into a flow in the rotational direction of the classification rotor 13 by the auxiliary vanes 33. In the void 34, the air rotating in the rotational direction of the classification rotor 13 forms an air flow flowing toward the inside of the classification chamber 31. The air entering the classification chamber 31 moves along the classification vanes 28, passes through the first cavity portion 27 of the classification rotor 13 and the second cavity portion 35 of the balance rotor 14 as indicated by the arrows, and is drawn to the outside of the housing 12 via the spiral housing 22. At the same time, the negative pressure inside the housing 12 forms an air flow from the introduction port 18 to the classification chamber 31 via the flow path 17.

[0265] ​In this state, classification (manufacture) of the Mg-containing particles 24 is performed by feeding the unclassified Mg-containing particles 20 from the feed port 18. That is, the unclassified Mg-containing particles 20 fed from the feed port 18 along with the air are dispersed substantially uniformly in the radial direction centered on the axis of the classification rotor 13 during the period in which they pass through the flow path, and primary dispersion of the unclassified Mg-containing particles 20 is performed. In this way, in the process of supplying the unclassified Mg-containing particles 20 to the classification chamber 31, the average flow velocity of the unclassified Mg-containing particles 20 at the inlet 31A of the classification chamber 31 is reduced to less than half the average flow velocity of the unclassified Mg-containing particles 20 at the upstream end portion 17A. In addition, in the process of supplying the unclassified Mg-containing particles 20 to the classification chamber 31, the average flow velocity of the unclassified Mg-containing particles 20 at the substantially middle position of the radius of the classification rotor 13 is reduced to less than 2 / 3 the flow velocity of the unclassified Mg-containing particles 20 at the upstream end portion 17A. Furthermore, the average flow velocity of the unclassified Mg-containing particles 20 at the inlet 31A of the classification chamber 31 is 15 m / s or less. The unclassified Mg-containing particles 20 that have come out to the outside from the outer edge of the top surface 16 are radiated in the tangential direction of the outer edge of the classification rotor 13 with rotation of the classification rotor 13, and are subjected to secondary dispersion.

[0266] The unclassified Mg-containing particles 20 fed to the feed port 18 mostly form secondary particles in which primary particles are combined with one another to become a lump. In this primary dispersion and secondary dispersion, the secondary particles of the unclassified Mg-containing particles 20 are moderately broken apart by colliding with the top surface 16 of the classification rotor 13, the inner surface 19 of the housing 12, and the like, and are broken into the shape of primary particles. At this time, in the flow path 17, the flow velocity of the unclassified Mg-containing particles 20 at the time of supply to the classification chamber 31 is sufficiently reduced, so it is possible to prevent the unclassified Mg-containing particles 20 from colliding with the inner surface 19 of the housing 12, the top surface 16 of the classification rotor, and the like before being supplied to the classification chamber 31, and being damaged.

[0267] The unclassified Mg-containing particles 20 broken into the shape of primary particles are supplied to the classification chamber 31 through the openings 32. Here, the unclassified Mg-containing particles 20 are subjected to centrifugal force generated by rotation of the classification rotor 13 and resistance generated by air flowing in the radial direction. Of the unclassified Mg-containing particles 20, the classified Mg-containing particles 24 (product) for which the relationship centrifugal force > resistance holds fly into the empty space in the outer periphery of the classification rotor 13, and are taken out to the outside of the Mg-containing particle classification device 11 from the take-out port 21. In addition, the fine powder 24a, which is smaller in particle diameter and for which the relationship centrifugal force < resistance holds, is transported to the spiral housing 22 via the first cavity portion 27 of the classification rotor 13 and the second cavity portion 35 of the balance rotor 14 in a state in which it is accompanied by the air flow in the radial direction. The fine powder 24a is collected and removed by a collection device connected to the spiral housing 22.

[0268] According to the present embodiment, the following can be said. The Mg-containing particle classification device 11, which is provided in the housing 12 having the inlet 18 below the inlet 18 and classifies the unclassified Mg-containing particles 20 in the classification chamber 31 on the outer edge side of the rotating classification rotor 13 to obtain the Mg-containing particles 24a, has a flow path 17 defined by the inner surface of the housing 12 and the top surface 16 of the rotating body rotating in the housing 12, and connects the inlet 18 and the classification chamber 31 to reduce the flow rate of the unclassified Mg-containing particles 20 flowing inside.

[0269] The method for producing Mg-containing particles includes the steps of: reducing the average flow rate of the unclassified Mg-containing particles 20 on the downstream side of the upstream end portion 17A in the flow path 17 formed by the inner surface of the housing 12 and the top surface 16 of the rotating body rotating in the housing 12, which connects the upstream end portion 17A and the classification chamber 31 on the outer edge side of the rotating body, to be smaller than the average flow rate of the unclassified Mg-containing particles 20 at the upstream end portion 17A inside the flow path 17, and supplying the unclassified Mg-containing particles 20 to the classification chamber 31; and classifying the unclassified Mg-containing particles 20 in the classification chamber 31 to obtain the Mg-containing particles 24a, the attrition durability A (%) of the unclassified Mg-containing particles 20 calculated by the following formula (1) being 85 or less.

[0270] A = (Z ÷ Y) x 100 (1)

[0271] In the formula, Y represents the average particle size D 50 (μm) measured automatically in a dry manner at a blow pressure of 0.4 bar using a laser diffraction type particle size distribution measuring device, and Z represents the average particle size D 50 (μm) measured automatically in a dry manner at a blow pressure of 1.0 bar using the laser diffraction type particle size distribution measuring device.

[0272] According to these configurations, the flow rate of the unclassified Mg-containing particles 20 can be sufficiently reduced in the flow path 17, and thus the energy at the time of collision can be reduced even in the case where the unclassified Mg-containing particles 20 collide with the inner surface 19 of the housing 12 or the like before being supplied to the classification chamber 31. Thus, the unclassified Mg-containing particles 20 can be moderately broken in such a manner that secondary particles become primary particles, and the unclassified Mg-containing particles 20 can be prevented from being more finely broken from the desired shape of the primary particles. Thus, the yield of the Mg-containing particles 24 after the classification process can be improved. In addition, according to the above configurations, even in the case where the so-called easily broken unclassified Mg-containing particles 20 are used, the breakage of the unclassified Mg-containing particles 20 can be prevented and the yield of the Mg-containing particles 24 after the classification process can be improved.

[0273] In this case, in the step of supplying the unclassified Mg-containing particles 20 to the flow path 17 of the Mg-containing particle classifying device 11 and the classifying chamber 31 in the manufacturing method of the Mg-containing particles, the average flow velocity of the unclassified Mg-containing particles 20 at the inlet 31A of the classifying chamber 31 is reduced to half or less of the average flow velocity of the unclassified Mg-containing particles 20 at the upstream end portion 17A. According to this configuration, the energy at the time of collision with the inner surface 19 or the like of the housing 12 can be reduced, and the Mg-containing particles 24 can be prevented from being more finely broken from the desired shape of primary particles. Thus, the yield of the classified Mg-containing particles 24 after the classifying process can be improved.

[0274] In the step of supplying the unclassified Mg-containing particles 20 to the classifying chamber 31, the average flow velocity of the unclassified Mg-containing particles 20 at the substantially middle position of the radius of the top surface 16 of the classifying rotor 13 is 2 / 3 or less of the average flow velocity of the unclassified Mg-containing particles 20 at the upstream end portion 17A. According to this configuration, the flow velocity of the unclassified Mg-containing particles 20 flowing in the flow path 17 can be greatly reduced in the first half of the flow path 17. Thus, even if the unclassified Mg-containing particles 20 collide with the inner surface 19 of the housing in the second half of the flow path 17, the energy at the time of collision can be greatly reduced. Therefore, for example, compared with a structure in which the flow velocity of the unclassified Mg-containing particles 20 is reduced in the second half of the flow path 17, the yield of the classified Mg-containing particles 24 after the classifying process can be further improved.

[0275] In this case, in the step of supplying the unclassified Mg-containing particles 20 to the flow path 17 of the Mg-containing particle classifying device 11 and the classifying chamber 31 in the manufacturing method of the Mg-containing particles, the average flow velocity of the unclassified Mg-containing particles 20 at the inlet 31A of the classifying chamber 31 is reduced to 15 m / s or less. According to this configuration, by suppressing the flow velocity of the unclassified Mg-containing particles 20 immediately before being supplied to the classifying chamber 31, even if the unclassified Mg-containing particles 20 collide with the inner surface 19 of the housing 12, the energy at the time of collision can be reduced. Thus, the yield of the classified Mg-containing particles 24 manufactured by the Mg-containing particle classifying device 11 can be significantly improved.

[0276] The housing 12 has a first portion 12A provided at a position opposite to the top surface 16 at a first predetermined distance from the top surface 16, and a second portion 12B provided at a position opposite to the top surface 16 on the side of the inlet 18 from the first portion 12A at a second predetermined distance larger than the first predetermined distance from the top surface 16.

[0277] According to this configuration, by increasing the cross-sectional area of the flow path 17 at a position corresponding to the second portion 12B near the inlet port 18, the flow rate of the unclassified Mg-containing particles 20 through the flow path 17 on the upstream side of the flow path 17 can be greatly reduced. Thus, even if the unclassified Mg-containing particles 20 collide with the inner surface 19 of the housing 12 on the downstream side of the flow path 17, the energy at the time of collision can be reduced. Therefore, the yield of the classified Mg-containing particles 24 produced by the Mg-containing particle classifying device 11 can be significantly improved.

[0278] The second portion 12B is inclined so as to be farther from the top surface 16 as it approaches the inlet port 18. According to this configuration, the cross-sectional area of the flow path 17 can be gradually increased as it approaches the inlet port 18. Thus, the flow rate of the unclassified Mg-containing particles 20 can be actively reduced on the side near the inlet port 18. Therefore, even if the unclassified Mg-containing particles 20 collide with the inner surface 19 of the housing 12 on the downstream side of the flow path 17, the energy at the time of collision can be reduced. Note that, according to this configuration, the cross-sectional area of the flow path 17 is apparently considered to be reduced as it moves away from the inlet port 18, but in reality, since the flow path 17 expands radially with the inlet port 18 as the center, the cross-sectional area of the flow path 17 does not actually greatly decrease as it moves away from the inlet port 18.

[0279] In this case, the top surface 16 is formed in a substantially flat shape. In the conventional classifying device, a dispersing blade is provided on the top surface 16 of the classifying rotor 13, and the particles are dispersed by the dispersing blade. Thus, although the dispersion and breakage of the particles can be made efficient, the acceleration of the particles toward the outer edge of the top surface 16 is promoted by the air blowing action caused by the dispersing blade. The inventors have found the following problem: the acceleration of the particles caused by the dispersing blade increases the energy at the time of collision of the unclassified Mg-containing particles 20 with the inner surface 19 of the housing 12, the top surface 16 of the classifying rotor 13, or the like, and as a result, the unclassified Mg-containing particles 20 are damaged, deteriorating the yield of the classified Mg-containing particles 24. According to the above-described configuration, no protruding object such as a dispersing blade is provided on the top surface 16 of the classifying rotor 13. Therefore, compared to the case where a dispersing blade is provided, the flow rate of the unclassified Mg-containing particles 20 can be suppressed. Thus, the energy at the time of collision of the unclassified Mg-containing particles 20 with the inner surface 19 of the housing, or the like, can be reduced, and the yield of the Mg-containing particles 24 after the classifying process can be improved.

[0280] In this case, the substantially flat shape includes a frustum-shaped tapered portion 16B at a position opposite the inlet port 18. According to this configuration, the cross-sectional area of the flow path 17 can be ensured to be large near the inlet port 18 of the flow path 17. Thus, the flow rate of the unclassified Mg-containing particles 20 can be actively reduced on the side near the inlet port 18, and thus the yield of the Mg-containing particles 24 after the classifying process can be improved.

[0281] The above embodiments can be implemented by applying various substitutions and modifications. In addition, the above embodiments can also be appropriately combined with each other to realize the invention.

[0282] (Reference Implementation Method)

[0283] Reference Figs. 5 to 8 The classification device 41 of the reference embodiment will be described below. In the following description, the differences from the Mg-containing particle classification device 11 of the above embodiment will be the main focus.

[0284] The grading device 41 of the reference embodiment includes a housing 12 covering the whole, a grading rotor 13 and a balancing rotor 14 disposed in the housing 12, a rotating shaft 15 supporting and rotating the grading rotor 13 and the balancing rotor 14, a motor (not shown) for rotating and driving the rotating shaft 15, and a flow path 17 defined by the top surface 16 of the housing 12 and the grading rotor 13.

[0285] like Figs. 5 to 8 As shown, the grading rotor 13 has a plurality of dispersing blades 42 on its top surface 16. The plurality of dispersing blades 42 rise upwards from the flat portion 16A of the top surface 16 and extend along the radial direction of the grading rotor 13. The plurality of dispersing blades 42 are separated from each other. The conical portion 16B of the top surface 16 is formed in a conical shape. The inlet 18 of the housing 12 has a constricted neck 43 in such a way that the cross-sectional area of ​​the flow path 17 on its inner side decreases midway.

[0286] The operation of the grading device 41 in the reference embodiment will be explained. Similar to the Mg-containing particle grading device 11 of the above embodiment, the grading device 41 in the reference embodiment forms an airflow from the inlet 18 through the flow path 17 to the grading chamber 31 by generating a negative pressure inside the housing 12. If ungraded Mg-containing particles 20 are introduced through the inlet 18, the ungraded Mg-containing particles 20 are supplied to the grading chamber 31 along with this airflow. At this time, the ungraded Mg-containing particles 20 pass through the flow path 17 through the gap 44A between the dispersing blades 42, or through the gap 44B between the dispersing blades 42 and the inner surface 19 of the housing 12. By passing through a relatively narrow space in this way, the flow velocity of the ungraded Mg-containing particles 20 is maintained at a relatively high level. In particular, the flow velocity of particles passing through the gap 44A between the dispersing blades 42 is significantly increased due to the airflow from the dispersing blades 42 (the action of a fan).

[0287] In the grading apparatus 41 of the reference embodiment, the flow rate of ungraded Mg-containing particles 20 entering the grading chamber 31 is significantly increased. As a result, before entering the grading chamber 31, these particles collide with the inner surface 19 of the housing 12, the top surface 16 of the grading rotor 13, and the dispersing blades 42, causing damage due to impact. Therefore, in the grading apparatus 41 of the reference embodiment, the yield of Mg-containing particles 24 after grading deteriorates. Furthermore, in the grading apparatus 41 of the reference embodiment, the problem of deteriorated yield is further amplified when using easily damaged ungraded Mg-containing particles 20.

[0288] Example

[0289] (Example A1)

[0290] Example A1 of the Mg-containing particle classification device 11 described in the above embodiments will be described. In Example A1, the flow path 17 of the Mg-containing particle classification device 11 described in the above embodiments was imitated, and the flow velocity of unclassified Mg-containing particles passing through the flow path 17 was analyzed using fluid analysis software. CAD shape creation was performed using ANSYS SCDM, and flow velocity analysis was performed using ANSYS Fluent. To ensure objectivity, the actual analysis work was outsourced to a third-party organization (Cybernet System Co., Ltd.) unrelated to the applicant.

[0291] The analytical model of the Mg-containing particle classification device in Example A1 sets the dimensions of each part of the flow path 17 as follows: Fig. 2 The dimensions shown are a = 17.3 mm, b = 19 mm, c = 13.97 mm, and d = 11 mm. Additionally, the diameter of the grading rotor 13 is set to 380 mm. The amount of ungraded Mg-containing particles fed into the inlet 18 is set to 5.611 × 10⁻⁶ mm. -3 The air flow rate at inlet 18 is set to 0.190049 kg / s. The rotational speed of the stage rotor 13 is set to 1350 rpm. The pressure (outlet pressure) of stage chamber 31 is set to 0.0 Pa (gauge pressure simulates open atmosphere). The working fluid is nitrogen, a fluid whose compressibility is taken into account. The density of unstaged Mg-containing particles is set to 2060 kg / m³. 3 The particle size of the unclassified Mg-containing particles was set to 4.13 × 10⁻⁶. -5 m. The coefficient of restitution of the ungraded Mg-containing particles relative to the shell 12 and the graded rotor 13 is set to 0.1.

[0292] The analysis results show that the flow rates of unclassified Mg-containing particles in each section are as follows. Fig. 3The average flow rate of the unclassified Mg-containing particles at the position of the indicated A-A line was 26.342 m / s, and the average flow rate of the unclassified Mg-containing particles at the position of the indicated B-B line was 34.184 m / s. Fig. 4 The average flow rate of the unclassified Mg-containing particles at the position of the indicated C-C line was 30.713 m / s, the average flow rate of the unclassified Mg-containing particles at the position of the indicated D-D line was 20.939 m / s, the average flow rate of the unclassified Mg-containing particles at the position of the indicated E-E line was 20.434 m / s, and the average flow rate of the unclassified Mg-containing particles at the position of the indicated F-F line was 12.677 m / s. The results are shown in Table 1. The unit is m / s.

[0293] [Table 1]

[0294]

[0295] Therefore, in Example Al, the average flow rate of the unclassified Mg-containing particles gradually decreases as it travels from the inlet 18 through the flow path 17 toward the classification chamber 31. In particular, it can be understood that the average flow rate of the unclassified Mg-containing particles at the inlet 31A of the classification chamber 31 (the position of the F-F line) is reduced to less than half of the average flow rate of the unclassified Mg-containing particles at the upstream end portion 17A (the position of the B-B line). In addition, the average flow rate of the unclassified Mg-containing particles at the inlet 31A of the classification chamber 31 (the position of the F-F line) is suppressed to be less than 15 m / s.

[0296] Furthermore, the average flow rate of the unclassified Mg-containing particles at the approximately middle position of the radius of the classification rotor 13 (the position of the E-E line) is reduced to less than 2 / 3 of the average flow rate of the unclassified Mg-containing particles at the upstream end portion 17A (the position of the B-B line). Therefore, it can be understood that in the Mg-containing particle classification device 11 of Example Al, the average flow rate of the unclassified Mg-containing particles is greatly reduced at the upstream side of the flow path 17.

[0297] (Comparative Example Al)

[0298] In Comparative Example Al, the flow path 17 of the classification device 41 described in the above reference embodiment was imitated, and the flow rate of the unclassified Mg-containing particles through this flow path 17 was analyzed using a fluid analysis software. The CAD shape creation used ANSYS SCDM, and the analysis of the flow rate used ANSYS Fluent. The actual analysis work was outsourced to a third-party organization (Cybernet System Co., Ltd.) that is not related to the applicant in order to ensure objectivity.

[0299] The analysis model of the classification device 41 of Comparative Example Al was set up imitating the actual machine shown. Figs. 5 to 8 That is, it was set up so that Fig. 5The dimensions a = 11 mm, dimension b = 5.97 mm, dimension c = 1 mm, dimension d = 3.25 mm are shown. The inlet 18 has a neck portion 43 with an inner diameter of 50 mm, which is smaller than the portion with the largest inner diameter of the inlet 18, which is 90 mm. The gap width between the dispersing vanes is 6 mm.

[0300] Further, the diameter of the classification rotor 13 was set to 380 mm. The amount of the unclassified Mg-containing particles fed to the inlet 18 was set to 5.611 x 10 -3 kg / s, and the flow rate of air at the inlet 18 was set to 0.190049 kg / s. The rotational speed of the classification rotor 13 was set to 1350 rpm. The classification chamber pressure (outlet pressure) was set to 0.0 Pa (atmospheric opening was simulated as a gauge pressure). The working fluid was set to nitrogen as a fluid in which compressibility was taken into account. The density of the unclassified Mg-containing particles was set to 2060 kg / m 3 , and the particle diameter of the unclassified Mg-containing particles was set to 4.13 x 10 -5 m. The recovery coefficient of the unclassified Mg-containing particles with respect to the casing 12 and the classification rotor 13 was set to 0.1.

[0301] As a result of the analysis, the flow rates of the unclassified Mg-containing particles in each portion were as follows. Fig. 6 The average flow rate of the unclassified Mg-containing particles at the position of the A-A line shown was 63.563 m / s, and the average flow rate of the unclassified Mg-containing particles at the position of the B-B line was 56.237 m / s. Fig. 7 The average flow rate of the unclassified Mg-containing particles at the position of the C-C line shown was 41.187 m / s, the average flow rate of the unclassified Mg-containing particles at the position of the D-D line was 71.931 m / s, the average flow rate of the unclassified Mg-containing particles at the position of the E-E line was 120.161 m / s, and the average flow rate of the unclassified Mg-containing particles at the position of the F-F line was 43.439 m / s. The results are shown in Table 1.

[0302] Further, at the positions of the D-D line and the E-E line, the average flow rates were different at the positions between the dispersing vanes 42 (gap 44A) and at the positions between the dispersing vanes 42 and the casing 12 (gap 44B). The average flow rate at the positions between the dispersing vanes 42 at the position of the D-D line was 76.262 m / s, and the average flow rate at the positions between the dispersing vanes 42 and the casing 12 at the position of the D-D line was 43.419 m / s. The average flow rate at the positions between the dispersing vanes 42 at the position of the E-E line was 136.431 m / s, and the average flow rate at the positions between the dispersing vanes 42 and the casing 12 at the position of the E-E line was 101.533 m / s. The results are shown in Table 2. The unit is m / s.

[0303] [Table 2]

[0304] D-D line E-E line Between the dispersion blades 76.262 136.431 Between the dispersion blades and the housing 43.419 101.533

[0305] Therefore, in Comparative Example Al, the flow rate of the unclassified Mg-containing particles at the position near the neck portion 43 (the position of the A-A line) has become higher than that of Example Al.

[0306] In Comparative Example Al, the unclassified Mg-containing particles are accelerated in the range from the position of the C-C line to the position of the D-D line by the air-blowing action of the dispersing vanes 42, and the unclassified Mg-containing particles are further accelerated in the range from the position of the D-D line to the position of the E-E line. Thus, in Comparative Example Al, it is understood that the flow rate of the unclassified Mg-containing particles at the position outside the dispersing vanes 42 is accelerated to about twice the flow rate of the unclassified Mg-containing particles at the position near the injection port 18.

[0307] Further, it is understood from the results of Table 2 that the position (gap 44A) between the dispersing vanes 42 is greatly increased in the flow rate of the unclassified Mg-containing particles due to the air-blowing action of the dispersing vanes 42, as compared with the position (gap 44B) between the dispersing vanes 42 and the housing 12.

[0308] (Production Example 1)

[0309] <Preparation of solid catalyst component>

[0310] According to the method for preparing a solid catalyst component described in Japanese Patent No. 6515038 (Example 1), about 60 kg of a powdery solid catalyst component (unclassified product) N1 was obtained.

[0311] Specifically, in a flask having a stirring device and a content volume of 500 mL, which was replaced with nitrogen, diethoxy magnesium 10 g (87.4 mmol), toluene 55 mL, titanium tetrachloride 30 mL, (2-ethoxyethyl)ethyl carbonate (A) 9 mmol (1.46 g), and 2-isopropyl-2-isopentyl-l,3-dimethoxypropane (B) 1.2 mmol (0.26 g) were added, and the reaction was performed at a temperature of 100°C for 90 minutes. After the reaction was completed, the reaction product was washed with toluene 75 mL at 100°C four times. Next, a toluene solution of titanium tetrachloride 10% by volume 100 mL was newly added, the temperature was raised to 100°C, and the reaction was performed by stirring for 15 minutes. After the reaction, the product was washed with toluene at 100°C once. This operation was further performed twice, and then washed with n-heptane 75 mL at 40°C six times. The residual solvent was removed by drying under reduced pressure, and a solid catalyst component (unclassified product) N1 was obtained.

[0312] The particle size distribution of the obtained solid catalyst component (unclassified product) N1 was measured. The results are shown in Table 3. Note that the attrition durability of the solid catalyst component (unclassified product, unclassified Mg-containing particles) N1 was measured, and the result was 73%.

[0313] [Table 3]

[0314]

[0315] <Method for calculating attrition durability of solid catalyst component>

[0316] The particle size distribution of the obtained solid catalyst component was measured automatically using a laser diffraction particle size distribution measuring device (Spectris Co., Ltd., Mastersizer 3000) equipped with a dry powder dispersion unit (Spectris Co., Ltd., Aero S) at air blow pressures of 0.4 bar and 1.0 bar, respectively, and the D 50 values obtained were used to calculate the attrition durability A (%) by the following formula (1).

[0317] Attrition durability A (%) = (Z ÷ Y) x 100 … (1)

[0318] In the formula, Y represents the average particle size D 50 (μm) measured automatically using the laser diffraction particle size distribution measuring device at an air blow pressure of 0.4 bar, and Z represents the average particle size D 50 (μm) measured automatically using the laser diffraction particle size distribution measuring device at an air blow pressure of 1.0 bar.

[0319] <Method for calculating particle size distribution and average particle size of solid catalyst component>

[0320] A laser scattering / diffraction particle size measuring machine (MT-3300EX: manufactured by NIKKISO CO., LTD.) was used to measure the particle size distribution of the solid catalyst component. The powder of the solid catalyst component was put into n-heptane solvent to which tridecylaluminum had been added in advance, so that the solid catalyst component was contained in the range of 0.05 g to 0.20 g within the optimum dispersion concentration range shown by the device, and the volume-based cumulative particle size was measured automatically. In addition, the particle size distribution index (SPAN) was calculated by the following formula (ii). As the average particle size, the value of D 50 was used. The results are shown in Table 3.

[0321] Particle size distribution index (SPAN) = (D 90 -D 10 ) / D 50 … (ii)

[0322] (D 10 , D 50 , and D90 D10, D50, and D90 refer to the particle diameters of 10%, 50%, and 90%, respectively, in terms of the cumulative particle size by volume, as measured using the above-described measuring machine.

[0323] Note that the particle diameter of each particle was automatically calculated by assuming a circle having the same circumference as the circumference length diameter, i.e., the circumference of the projection image of each particle, and calculating the diameter thereof.

[0324] (Production Example 2)

[0325] <Preparation of solid catalyst component>

[0326] Approximately 60 kg of the solid catalyst component N2 (unclassified product) in powder form was obtained according to the method for preparing a solid catalyst component described in Japanese Patent No. 6343561 (Example 11).

[0327] Specifically, a round-bottom flask having a stirring device and a content volume of 500 mL, which was replaced with nitrogen, was charged with titanium tetrachloride 70 mL and toluene 70 mL to form a mixed solution, and the liquid temperature was maintained at -10°C. Next, a round-bottom flask having a stirring device and a content volume of 200 mL, which was replaced with nitrogen, was charged with diethoxy magnesium (average particle diameter: 54 μm) 20 g, toluene 70 mL, and ethanol 0.25 mL (1.0 part by mass with respect to 100 parts by mass of diethoxy magnesium) to form a suspension, and further, di-n-butyl phthalate 26.3 mmol (7.0 mL) was added. After the suspension was added all at once to the above-described mixed solution, which was previously maintained at a liquid temperature of -10°C, the temperature of the flask was increased from -10°C to 110°C, and the reaction was allowed to proceed while stirring at 110°C for 3 hours. After the reaction was completed, the obtained solid product was washed with toluene 167 mL at 100°C for 4 times. Then, toluene 123 mL at normal temperature and titanium tetrachloride 20 mL were newly added, and the temperature was increased to 110°C, and the reaction was allowed to proceed while stirring for 2 hours. After the reaction was completed, the supernatant was removed, and n-heptane 125 mL at 40°C was used to wash the product for 8 times, thereby obtaining the solid catalyst component (unclassified product) N2.

[0328] The particle size distribution of the obtained solid catalyst component (unclassified product) N2 was measured. Note that the attrition durability of the solid catalyst component N2 (unclassified product, Mg-containing particles unclassified) was measured, and the result was 72%. The result is shown in Table 3.

[0329] (Production Example 3)

[0330] <Preparation of solid catalyst component>

[0331] Approximately 60 kg of the solid catalyst component (unclassified product) N3 in powder form was obtained according to the method for preparing a solid catalyst component described in Japanese Patent No. 3258226 (Example 1).

[0332] Specifically, a round bottom flask having a content volume of 500 mL equipped with a stirring device and subjected to nitrogen replacement was charged with titanium tetrachloride 30 mL and toluene 20 mL to form a mixed solution. Next, a suspension of diethoxy magnesium 10 g having an average particle diameter of 32 μm, a fine powder content rate of 5% or less at 5 μm or less, a particle size distribution index (SPAN) [(D 90 -D 10 ) / D 50 ) 1.05, toluene 50 mL, and di-n-butyl phthalate 3.6 mL was added to the above mixed solution maintained at a liquid temperature of 10°C. Thereafter, the liquid temperature was increased from 10°C to 90°C over 80 minutes, and the reaction was allowed to proceed while stirring for 2 hours. After completion of the reaction, the obtained solid product was washed with toluene 100 mL at 90°C for 4 times, and titanium tetrachloride 30 mL and toluene 70 mL were newly added, and the temperature was increased to 112°C, and the reaction was allowed to proceed while stirring for 2 hours. After completion of the reaction, n-heptane 100 mL at 40°C was used for washing for 10 times, and a solid catalyst component (unclassified product) N3 was obtained.

[0333] The particle size distribution of the obtained solid catalyst component (unclassified product) N3 was measured. Note that the attrition durability of the solid catalyst component (unclassified product) N3 was measured, and the result was 91%. The result is shown in Table 3.

[0334] (Production Example 4)

[0335] <Preparation of solid catalyst component>

[0336] Diethoxy magnesium (average particle diameter 32 μm, fine powder content rate 5% or less at 5 μm or less, particle size distribution index (SPAN) [(D 90 -D 10 ) / D 50 ] 1.05) 10 g was changed to other diethoxy magnesium (average particle diameter (D 50 ) 37.5 μm to 43.5 μm, fine powder content rate 8.0% or less at 10.5 μm or less, particle size distribution index (SPAN) [(D 90 -D 10 ) / D 50 ] 1.0 or less) 10 g, and otherwise, according to the method for preparing a solid catalyst component described in Japanese Patent No. 3258226 (Example 1), a powder-like solid catalyst component (unclassified product) N4 of about 60 kg was obtained. The particle size distribution of the obtained solid catalyst component (unclassified product) N4 was measured. Note that the attrition durability of the solid catalyst component (unclassified product) N4 was measured, and the result was 87%. The result is shown in Table 3.

[0337] (Examples B1, B2)

[0338] <Classification of solid catalyst component>

[0339] The solid catalyst component Nl of the unclassified product obtained in Production Example 1 was charged into a pneumatic classifier (Nitto Kogyo Co., Ltd., TC-40III) having a disc-shaped classification rotor with a diameter of 400 mm, and under conditions of a rotation speed of the classification rotor of 1,290 rpm, a total air flow of 10 m 3 / minute, a circulating air flow of 6 m 3 / minute, and a solid catalyst component supply amount of 27.9 kg / h, a pneumatic classification treatment was performed for 1,360 minutes to obtain a solid catalyst component (classified product, Mg-containing particles) Cl from which a fine coarse powder component was removed. The TC-40III is the catalyst particle classification device 11 described in the above-described embodiment. The product yield of the solid catalyst component (classified product) Cl was 90.4 mass%, and the surface shape of the particles was also good. The results are shown in Table 4.

[0340] <Particle size distribution of solid catalyst component (classified product)>

[0341] The particle size distribution of the obtained solid catalyst component (classified product) Cl was measured in the same manner as the above-described solid catalyst component (unclassified product) Nl. The results are shown in Table 4. In addition, the correspondence before and after the classification process and the classification conditions of each example are shown in Table 5.

[0342] [Table 4]

[0343]

[0344] [Table 5]

[0345]

[0346] <Preparation of catalyst for polymerization>

[0347] Into a nitrogen-substituted autoclave with a stirrer, an internal volume of 2.0 liters, equipped with a stirrer, 0.092 millimoles of triethylaluminum, 0.092 millimoles of cyclohexylmethyldimethoxysilane, and 0.0018 millimoles of the above-described solid catalyst component (classified product, Mg-containing particles) Cl were charged to prepare an olefin polymerization catalyst.

[0348] <Propylene polymerization>

[0349] Into the autoclave with a stirrer containing the above-described prepared olefin polymerization catalyst, 1.6 liters of hydrogen and 1.0 liters of liquefied propylene were charged, and after a preliminary polymerization of 5 minutes at 20°C, the temperature was raised to 70°C, and a polymerization reaction was performed for 1 hour at 70°C to produce a propylene homopolymer (PP).

[0350] <Amount of fine powder, amount of coarse powder, average particle diameter, particle size distribution index (SPAN) of the polymer>

[0351] The volume-based cumulative particle size distribution of the obtained polymer was automatically measured under the following measurement conditions using a digital image analysis particle size distribution measuring device (Camsizer, manufactured by Horiba Ltd.), and the amount of fine powder (mass %) having a particle size of less than 75 μm, the amount of coarse powder (mass %) having a particle size of more than 1700 μm, and the particle size at the time of 50% of the volume-based cumulative particle size (average particle diameter D 50 ) were measured. The particle size distribution index (SPAN) was calculated by the above-described formula (ii). The results are shown in Table 6.

[0352] [Table 6]

[0353]

[0354] (Measurement conditions)

[0355] Funnel position: 6 mm

[0356] Camera coverage area: less than 3% for the basic camera and less than 10% for the zoom camera

[0357] Target coverage area: 0.5%

[0358] Feeder width: 40 mm

[0359] Feeder control level: 57, 40 seconds

[0360] Measurement start level: 47

[0361] Maximum control level: 80

[0362] Control reference: 20

[0363] Image rate: 50% (1:2)

[0364] Particle size definition: minimum value of the Martin diameter obtained by measuring n times for each 1 particle

[0365] SPHT (sphericity) fitting: 1

[0366] Rank upper limit value: logarithmic scale, 50 points selected in the range of 32 μm to 4000 μm

[0367] (Comparative Example B1)

[0368] The solid catalyst component N1 obtained in Production Example 1 was subjected to air classification treatment. In the classification of the solid catalyst component, an air classifier (Nisshin Engineering, Inc., TC-40III) having a disc-shaped classification rotor with a diameter of 400 mm was changed to an air classifier (Nisshin Engineering, Inc., TC-40) having a disc-shaped classification rotor with a diameter of 400 mm, the classification time was changed from 1,360 minutes to 480 minutes, and the solid catalyst component supply amount was changed from 27.9 kg / h to 26.6 kg / h, and otherwise, the solid catalyst component (classified product) C11, the polymerization catalyst, and the olefin polymer were obtained in the same manner as in Example B1, and each property was evaluated. Note that the TC-40 is the classification device 41 described in the above Reference Example. Note that the product yield of the obtained solid catalyst component (classified product) C11 was 75.9 mass%. The results are shown in Tables 4, 6.

[0369] (Example B2)

[0370] The solid catalyst component (unclassified product) N2 obtained in Production Example 2 was charged into an air classifier (Nisshin Engineering, Inc., TC-40III) having a disc-shaped classification rotor with a diameter of 400 mm, and was subjected to air classification treatment for 1,160 minutes under conditions of a rotation speed of 1,270 rpm, a total air volume of 12 m 3 / minute, a circulating air volume of 8 m 3 / minute, and a solid catalyst component supply amount of 18.0 kg / h, to obtain a solid catalyst component (classified product, Mg-containing particles) C2 from which the fine coarse powder component was removed. The product yield of the solid catalyst component (classified product) C2 was 88.1 mass%, and the surface shape of the particles was also good. In addition, the obtained solid catalyst component (classified product, Mg-containing particles) C2 was used to obtain a polymerization catalyst and an olefin polymer in the same manner as in Example 1, and each property was evaluated. The results are shown in Tables 4, 6.

[0371] (Comparative Example B2)

[0372] The solid catalyst component N2 obtained in Production Example 2 was subjected to air classification treatment. In the classification of the solid catalyst component, an air classifier (Nisshin Engineering, Inc., TC-40 III) having a disc-shaped classification rotor with a diameter of 400 mm was changed to an air classifier (Nisshin Engineering, Inc., TC-40) having a disc-shaped classification rotor with a diameter of 400 mm, the solid catalyst component supply amount was changed from 18.0 kg / h to 18.1 kg / h, and otherwise, the solid catalyst component (classified product) C21, the polymerization catalyst, and the olefin polymer were obtained in the same manner as in Example B2, and each property was evaluated. Note that the product yield of the obtained solid catalyst component (classified product) C21 was 81.8 mass%. The results are shown in Tables 4, 6.

[0373] (Reference Example B1)

[0374] The solid catalyst component (unclassified product) N3 obtained in Production Example 3 was charged to an air classifier (Nisshin Engineering, Inc., TC-40) having a disc-shaped classification rotor with a diameter of 400 mm, and was subjected to air classification treatment for 680 minutes under conditions of a rotation speed of 1,495 rpm, a total air flow of 11 m 3 / minute, a circulating air flow of 7 m 3 / minute, and a solid catalyst component supply amount of 65.8 kg / h, to obtain a solid catalyst component (classified product) C3 from which the fine coarse powder component was removed. The product yield of this solid catalyst component (classified product) C3 was 91.4 mass%, and the surface shape of the particles was also good. In addition, using the obtained solid catalyst component (classified product) C3, the polymerization catalyst and the olefin polymer were obtained in the same manner as in Example B1, and each property was evaluated. The results are shown in Tables 4, 6.

[0375] (Reference Example B2)

[0376] The solid catalyst component (unclassified product) N4 obtained in Production Example 4 was charged to an air classifier (Nisshin Engineering, Inc., TC-40) having a disc-shaped classification rotor with a diameter of 400 mm, and was subjected to air classification treatment for 280 minutes under conditions of a rotation speed of 1,850 rpm, a total air flow of 14 m 3 / minute, a circulating air flow of 10 m 3 / minute, and a solid catalyst component supply amount of 54.3 kg / h, to obtain a solid catalyst component (classified product) C4 from which the fine coarse powder component was removed. The product yield of this solid catalyst component (classified product) C4 was 87.9 mass%, and the surface shape of the particles was also good. In addition, using the obtained solid catalyst component (classified product) C4, the polymerization catalyst and the olefin polymer were obtained in the same manner as in Example 1, and each property was evaluated. The results are shown in Tables 4, 6.

[0377] As can be understood from Tables 3, 4, and 6, in Embodiment B1 and Embodiment B2, in the Mg-containing particle classification device 11, by reducing the flow rate of the unclassified Mg-containing particles flowing in the flow path 17, the energy imparted to the unclassified Mg-containing particles at the time of collision of the unclassified Mg-containing particles with the inner surface of the housing and the top surface of the classification rotor is reduced, and breakage of the unclassified Mg-containing particles is prevented. Thus, the classified Mg-containing particles can maintain the same particle size distribution as in the past, and the product yield can be greatly improved, and furthermore, the shape of the classified particles is also good.

[0378] On the other hand, according to Tables 3, 4, and 6, in Comparative Embodiment B1 and Comparative Embodiment B2, the conventional classification device 41 increases the flow rate of the unclassified Mg-containing particles flowing in the flow path 17, and thus the energy imparted to the unclassified Mg-containing particles at the time of collision of the unclassified Mg-containing particles with the inner surface of the housing and the top surface of the classification rotor becomes large, resulting in breakage of the unclassified Mg-containing particles. Thus, it can be understood that the classified Mg-containing particles significantly decrease in product yield while maintaining the same particle size distribution as in the past.

[0379] Thus, the present application can provide a Mg-containing particle classification device and a method for producing Mg-containing particles, which can reduce the content of fine powder particles, coarse powder particles, and the like, and can moderately separate (crush) the particles from each other while preventing breakage of the particles, and have a narrow particle size distribution and a good particle shape.

[0380] Industrial Applicability

[0381] The present application is very useful in the case where a solid catalyst component, particularly a solid catalyst component which is small in particle strength and weak, is classified in the use of the solid catalyst component in the polymerization of olefins. The content of fine powder particles, coarse powder particles, and the like is reduced, and breakage of the particles is prevented, and a solid catalyst component having a narrow particle size distribution and a good particle shape is obtained. In addition, the present application can be applied not only to a solid catalyst component, but also to a porous body particle which is small in particle strength and weak, such as a metal oxide particle, a metal chloride particle, and the like, which are carriers of the solid catalyst component, and to an alkoxide metal particle and the like, which are a carrier material of the solid catalyst component, and is a very useful technology.

[0382] Explanation of Reference Numerals

[0383] 11, Mg-containing particle classifying device; 12, housing; 12A, 1st portion; 12B, 2nd portion; 12C, 3rd portion; 13, classifying rotor; 16, top surface; 16A, flat portion; 16B, tapered portion; 17, flow path; 18, inlet; 19, inner surface; 24, Mg-containing particle; 24a, particle (fines); 31, classifying chamber.

Claims

1. A method for manufacturing Mg-containing particles, comprising obtaining Mg-containing particles by performing a classification process using a centrifugal airflow classifier, the centrifugal airflow classifier comprising: a shell; a rotating body rotating within the shell; a classification chamber located on the outer edge of the rotating body; and a flow path formed by the inner surface of the shell and the top surface of the rotating body, connecting an upstream end to the classification chamber, wherein, The method for manufacturing Mg-containing particles includes the following steps: supplying the unclassified Mg-containing particles to the classification chamber by making the average flow velocity of the unclassified Mg-containing particles downstream of the upstream end in the flow path lower than the average flow velocity of the unclassified Mg-containing particles flowing inside the flow path at the upstream end; and classifying the unclassified Mg-containing particles in the classification chamber to obtain Mg-containing particles. The average flow velocity of the unclassified Mg-containing particles at the entrance of the classification chamber is below 15 m / s. The wear durability A (%) of the ungraded Mg-containing particles, calculated by the following formula (1), is 60-85: A=(Z÷Y)×100…(1) In the formula, Y represents the average particle size D measured automatically by a laser diffraction particle size distribution measuring device under a dry air pressure of 0.4 bar. 50 (μm), Z represents the average particle size D measured automatically by dry method using the laser diffraction particle size distribution measuring device at a supply air pressure of 1.0 bar. 50 (μm).

2. The method for manufacturing Mg-containing particles according to claim 1, wherein, In the process of supplying the unclassified Mg-containing particles to the classification chamber, the average flow velocity of the unclassified Mg-containing particles at the inlet of the classification chamber is less than half of the average flow velocity of the unclassified Mg-containing particles at the upstream end.

3. The method for manufacturing Mg-containing particles according to claim 1 or 2, wherein, In the process of supplying the unclassified Mg-containing particles to the classification chamber, the average flow velocity of the unclassified Mg-containing particles at approximately the midpoint of the radius of the top surface of the rotating body is less than 2 / 3 of the average flow velocity of the unclassified Mg-containing particles at the upstream end.

Images