JPH0995505A - Method for stopping olefin polymerization reaction in emergency - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stop an olefin polymerization reaction in an emergency within a short time by introducing a compound selected from among water, alcohols, molecular oxygen, CO2 and CO in polymerizing an olefin in a vapor phase in the presence of a specified catalyst. SOLUTION: A catalyst is prepared by bringing a compound containing a metal of group IV in the periodic table, a compound containing a metal of group I, II or III in the periodic table, an organic compound having a plurality of conjugated double bonds, a modified organoaluminum compound having an Al-O-Al bond and/or a boron compound and an inorganic compound support and/or a particulate polymer support into contact with each other. An olefin (e.g. ethylene) is (co)polymerized steadily in a vapor phase. When the emergency stop of the polymerization reaction is necessary, a compound selected from among water, alcohols, molecular oxygen, carbon dioxide and carbon monoxide is introduced into the reactor, whereupon the olefin polymerization reaction can be stopped within a short time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of operating a reactor when polymerizing or copolymerizing a polyolefin in a gas phase (hereinafter simply referred to as "polymerization"). More specifically, it relates to a method for urgently stopping the polymerization reaction when producing a polyolefin by a gas phase polymerization method.

[0002]

2. Description of the Related Art A method for producing a polyolefin by polymerizing an olefin in a gas phase is widely used because it can be carried out at a low cost. The type of reactor used for the gas phase polymerization of olefins is usually a fluidized bed type or a stirring type (for example, JP-B-47-13962, JP-A-51-8).
No. 6584). When producing a polyolefin by a gas phase polymerization method, there are cases where the operation of the polymerization reactor must be stopped urgently due to various troubles.
For example, the polymerization reaction proceeds excessively in the gas phase polymerization reactor,
If the removal of the heat of polymerization is insufficient and the temperature inside the vessel rises, there is a risk that the polymer particles will melt and become lumps, or trouble will occur in the subsequent steps of the polymerization reaction (pelletization, blending, etc.). In addition, when the intermediate storage tank for polymer particles is full and there is no room, or when a failure occurs in the circulating gas blower of the reaction system.

In such a case, the usual emergency stop and reaction restart methods are as follows. That is, a reaction terminator is supplied into the reactor to stop the polymerization reaction, and then the gas in the reaction system is purged with nitrogen. Then, the polyolefin particles remaining in the reactor are taken out of the reactor.
Next, when the operation is restarted, first, new polyolefin particles are again introduced into the reactor, the inside of the system is purged with nitrogen, and then the reaction start-up procedure is repeated.

At this time, the reaction terminator also differs depending on the type of catalyst used. Among the transition metal catalysts, in the case of a so-called Ziegler catalyst mainly containing titanium or vanadium, carbon dioxide, carbon monoxide, oxygen, water vapor, alcohols and ketones can be used as a reaction terminator ( For example, U.S. Pat. No. 430604
No. 4, JP 4326048, and JP-A-60-72.
904 publication, the same 6-199949 publication). Even when the same transition metal catalyst is used, when chromium oxide is used, oxygen, ammonia, water or carbon monoxide is used as a reaction terminator, and carbon dioxide is said to have no effect (JP-A-4-233922). Gazette). In recent years, a catalyst containing a metallocene compound as one component has been developed, and a Lewis base is used as a reaction terminator in this case. The Lewis base is specifically an ether, alcohol, ketone, aldehyde, carboxylic acid, ester, carbonate, phosphine, phosphine oxide, phosphate,
Phosphite, amine, amide, nitrile, alkoxysilane, aluminum alkoxide, water, nitric oxide, etc., and does not contain carbon dioxide and carbon monoxide (JP-A-7-25925).

[0005]

The catalyst used in the present invention generally has a property that the activity lasts for a long time, and the reaction does not stop immediately even if the supply of the catalyst to the polymerization reactor is stopped. Absent. Some catalyst systems of this type require several hours before the polymerization rate is reduced by half. It is necessary to actually shut down the gas phase polymerization reactor
This is a case where a block polymer is generated and the outlet pipe of the gas phase polymerization reactor is blocked. Only by stopping the supply of the catalyst, the polymer particles continue to be generated in the polymerization reactor and eventually overflow from the upper surface of the reactor.

Therefore, as a reaction terminator for urgently stopping the gas phase polymerization reaction using the above catalyst system, it is possible to completely stop the polymerization reaction with a small amount, and when it is in a gaseous state and is restarted. There has been a demand for a substance that can be easily removed by nitrogen purging. It should be noted that there is a case where the gas phase polymerization reaction device using the metallocene catalyst is continuously used and the catalyst is switched to a so-called Ziegler catalyst to produce a polyolefin, but in this case, the reaction terminator is common. Is preferred.

[0007]

Means for Solving the Problems As a result of intensive studies for solving the above-mentioned problems, the present inventors have found that a reaction terminator is selected from the group consisting of water, alcohol, molecular oxygen, carbon dioxide and carbon monoxide. The present invention has been accomplished by finding that the object can be achieved by supplying any selected compound. That is, the first aspect of the present invention is a reactor for constantly polymerizing or copolymerizing an olefin in a gas phase in the presence of a catalyst obtained by contacting the following components (1) to (5) with each other. An olefin polymerization reaction characterized by stopping the olefin polymerization reaction in a short period by introducing any of the compounds selected from the group consisting of water, alcohol, molecular oxygen, carbon dioxide and carbon monoxide into It relates to the stopping method. (1) A compound containing a Group IVB metal of the periodic table, (2)
A compound containing any of Group I to III metals of the periodic table,
(3) an organic cyclic compound having two or more conjugated double bonds,
(4) A modified organoaluminum compound having an Al-O-Al bond and / or a boron compound, (5) an inorganic compound carrier and / or a particulate polymer carrier.

A second aspect of the present invention is characterized in that, in the first aspect of the present invention, the olefin polymerization reaction is carried out in the presence of a catalyst obtained by bringing the following components (1) to (5) into contact with each other. The present invention relates to a method for urgently stopping an olefin polymerization reaction. (1) General formula Me ¹ (OR ¹ ) _p R ² _q X ¹ _4-pq (R ¹ and R ² are hydrocarbon groups, X ¹ is a halogen atom, Me ¹ is Ti, Zr or Hf, and 0 ≦ p ≦ 4, 0 ≦ q ≦ 4, and 0 ≦ p + q ≦
Compound represented by 4) (2) General formula Me ² (OR ³ ) _m R ⁴ _n X ² _3-mn (wherein R ³ ,
R ⁴ is a hydrocarbon group, X ² is a hydrogen atom or a halogen atom,
Me ² is a Group III metal of the periodic table, 0 ≦ m ≦ 3, 0 ≦ n ≦
3, and a compound represented by 0 ≦ m + n ≦ 3) (3) an organic cyclic compound having two or more conjugated double bonds (4) a modified organoaluminum compound having an Al—O—Al bond and / or a boron compound (3) 5) Inorganic compound carrier and / or particulate polymer carrier

The present invention will be further described below. The olefin used in the present invention usually has 2 to 8 carbon atoms,
Preferably 2 to 6 olefins such as ethylene, propylene, butene-1, pentene-1, hexene-1,
An α-olefin such as 4-methylpentene-1 may be mentioned. These can be used for homopolymerization or copolymerization at an appropriate ratio. Examples of the type of copolymerization include ethylene / propylene and ethylene / butene-
1, ethylene / pentene-1, ethylene / hexene-
1, copolymerization of ethylene such as ethylene / 4-methylpentene-1 with an α-olefin having 3 to 12 carbon atoms, and copolymerization of ethylene with two or more other α-olefins. Further, copolymerization using a diene is also possible for the purpose of modifying the polyolefin. The diene used for this purpose is butadiene, 1,4-hexadiene,
Examples thereof include ethylidene norbornene and dicyclopentadiene. The supply of olefin to the reaction system may be carried out alone, but preferably an appropriate inert carrier gas,
For example, it is supplied together with nitrogen.

Catalyst component (1) used in the present invention
Is a compound containing a Group IVB metal of the periodic table, preferably represented by the general formula Me ¹ (OR ¹ ) _p R ² _q X ¹ _4-pq . In the formula, R ¹ and R ² each represent a hydrocarbon group, preferably a hydrocarbon group having 1 to 24 carbon atoms, and more preferably 1 to 12 carbon atoms. Specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, an alkyl group such as a hexyl group, a vinyl group, an alkenyl group such as an allyl group, a phenyl group, an aryl group such as a tolyl group, a benzyl group, Examples thereof include aralkyl groups such as trityl group. These may have branches. When the component (1) has two or more R ¹ or R ² , those hydrocarbon residues may be the same or different. X ¹ is a halogen atom of fluorine, iodine, chlorine or bromine, and Me ¹ is Z
It represents r, Ti or Hf, and is preferably Zr. p
Is 0 ≦ p ≦ 4, q is 0 ≦ q ≦ 4, and p + q is 0 ≦ p +
Each of the conditions of q ≦ 4 is satisfied, preferably 0 <p + q
≦ 4.

Specific examples of the compound that can be used as the component (1) include tetramethoxyzirconium, tetraethoxyzirconium, tetrapropoxyzirconium, tetraisopropoxyzirconium, tetrabutoxyzirconium, tetrapentyloxyzirconium, tetraphenoxyzirconium and tetratolyl. Oxyzirconium, tetrabenzyloxyzirconium, tetraallylzirconium, tetraneophyllzirconium, tetramethylzirconium, tetraethylzirconium, tetrapropylzirconium, tetrabutylzirconium, tetraphenylzirconium, tetratolylzirconium, tetrabenzylzirconium, tetrachlorozirconium, triethoxy Monochloro zirconium, diethoxydichlorodiene Conium, monoethoxytrichlorozirconium, triisopropoxymonochlorozirconium, diisopropoxydichlorozirconium, monoisopropoxytrichlorozirconium, tetrabutoxyzirconium, tributoxymonochlorozirconium, dibutoxydichlorozirconium, monobutoxytrichlorozirconium, triphenoxymonochlorozirconium, di Phenoxydichlorozirconium, monophenoxytrichlorozirconium, tritolyloxymonochlorozirconium, ditolyloxydichlorozirconium, monotolyloxytrichlorozirconium, tetrabenzyloxyzirconium, tribenzyloxymonochlorozirconium, dibenzyloxydichlorozirconium, monobenzyloxytric B zirconium, tetrabromo zirconium, etc. tetraiodothyronine zirconium and the like. Further, a compound in which zirconium in the above zirconium compound is replaced with titanium and hafnium can also be used. Among these, tetrapropoxyzirconium, tetrabutoxyzirconium, tetrachlorozirconium and tetrabenzylzirconium are preferable. Further, these compounds can be used as a mixture of two or more kinds.

The component (2) is a compound containing any of the metals of groups I to III of the periodic table, preferably of the general formula Me
It is represented by ² (OR ³ ) _m R ⁴ _n X ² _3-mn . In the formula, Me ² represents a Group III metal of the periodic table, and includes boron, aluminum and the like. R ³ and R ⁴ each represent a hydrocarbon residue, preferably a hydrocarbon residue having 1 to 24 carbon atoms, more preferably 1 to 12 carbon atoms. Specifically, a methyl group, an ethyl group, a propyl group, Butyl group, pentyl group, hexyl group,
Alkyl group such as heptyl group, octyl group, decyl group,
Alkenyl group such as vinyl group and allyl group, phenyl group,
Examples thereof include an aryl group such as a tolyl group and an aralkyl group such as a benzyl group and a trityl group. These may have branches. If component (2) has more than one R ³ or R ⁴ , the hydrocarbon residues can be the same or different. X ² represents a hydrogen atom or a halogen atom, m is 0 ≦ m ≦ 3, n is 0 ≦ n ≦ 3, and m + n is 0 ≦ m + n ≦ 3.

Specific examples of the compound which can be used as the component (2) include trimethylboron, triethylboron, tri-n-propylboron, triisopropylboron, tri-n-butylboron, tri-tert-butylboron and tripentylboron. , Trioctylboron, triphenylboron, tribenzylboron, trimethylaluminum, triethylaluminum, diethylaluminum hydride, diethylaluminum chloride, ethylaluminum dichloride, tripropyloaluminum, dipropylaluminum hydride, dipropylaluminum chloride, propylaluminum dichloride, tri Isopropyl aluminum, diisopropyl aluminum hydride, diisopropyl aluminum chloride, ethyl Aluminum sesquichloride, propyl aluminum sesquichloride, isopropyl aluminum dichloride, tributyl aluminum, dibutyl aluminum chloride, butyl aluminum sesqui chloride, butyl aluminum dichloride, triisobutyl aluminum, diisobutyl aluminum hydride, diisobutyl aluminum chloride, trihexyl aluminum, dihexyl aluminum chloride, hexyl Aluminum dichloride,
Tripentyl aluminum, tridecyl aluminum,
Dimethyl aluminum methoxide, dimethyl aluminum ethoxide, dimethyl aluminum propoxide, dimethyl aluminum butoxide, diethyl aluminum ethoxide, diethyl aluminum propoxide, diethyl aluminum butoxide, diisobutyl aluminum methoxide, diisobutyl aluminum ethoxide,
Examples thereof include diisobutylaluminum propoxide and diisobutylaluminum butoxide. Among them, trimethylaluminum, triethylaluminum, diethylaluminum chloride, tripropyroaluminum, triisopropylaluminum, tributylaluminum, triisobutylaluminum, trihexylaluminum, tripentylaluminum, diisobutylaluminum hydride and tridecylaluminum are preferable.

As the component (3), an organic cyclic compound having two or more conjugated double bonds is used, preferably a cyclic carbonized compound having 2 to 4 conjugated double bonds and a total carbon number of 4 to 24. It is a hydrogen compound. Further, the cyclic hydrocarbon compound may be partially substituted with 1 to 6 hydrocarbon residues, and the hydrocarbon residue may contain a silicon atom.
Those having a cyclopentadiene structure in the molecule are particularly desirable.

Therefore, specific examples of the organic cyclic compound usable as the component (3) include cyclopentadiene, methylcyclopentadiene, ethylcyclopentadiene,
tert-butylcyclopentadiene, 1,2-dimethylcyclopentadiene, 1,3-dimethylcyclopentadiene, 1,2,3-trimethylcyclopentadiene, 1,2,
4-trimethylcyclopentadiene, 1-ethyl-4,
5-dimethylcyclopentadiene, 2-methyl-5-te
rt-butylcyclopentadiene, pentamethylcyclopentadiene, indene, methylindene, 4,7-dimethylindene, 4,5,6,7-tetrahydroindene, cycloheptatriene, cyclooctatetraene,
Examples thereof include azulene, methylazulene, fluorene, methylfluorene, cyclopentadienylsilane, cyclopentadienylmethylsilane, cyclopentadienyldimethylsilane, cyclopentadienyltrimethylsilane, indenylsilane and indenyltrimethylsilane.

A compound in which any of the above compounds is bound via a silicon atom or an alkylene group can also be used as the component (3) of the present invention. Specific examples are dicyclopentadienylsilane, dicyclopentadienylmonomethylsilane, dicyclopentadienyldimethylsilane, dicyclopentadienyldiphenylsilane, bis (3-methylcyclopentadienyl) silane, and bis. (3-Methylcyclopentadienyl) dimethylsilane, bis (1,3-dimethylcyclopentadienyl) silane, bis (1,3-dimethylcyclopentadienyl) dimethylsilane, diindenylsilane, diindenyldimethyl Silane, diindenyldiphenylsilane,
Bis (3-methylindenyl) silane, bisindenylethane, bis (4,5,6,7-tetrahydro-1-indenyl) ethane, 1,3-bisindenylpropane,
1,3-Bis (4,5,6,7-tetrahydroindenyl) propane, 2,2-bisindenylpropane, isopropyl (1-indenyl) cyclopentadiene, diphenylmethylene (9-fluorenyl) cyclopentadiene, isopropyl Examples thereof include cyclopentadienyl-1-fluorene.

Among them, cyclopentadiene, methylcyclopentadiene, ethylcyclopentadiene, tert-butylcyclopentadiene, 1,3-dimethylcyclopentadiene, 1,2,4-trimethylcyclopentadiene, indene, methylindene, 4,7-dimethylindene. ,
Diindenyldimethylsilane and bisindenylethane are preferred.

As the component (4), a modified organoaluminum compound having an Al--O--Al bond and / or a boron compound is used. The modified organoaluminum compound preferably contains 1 to 100, particularly preferably 1 to 50 Al-O-Al bonds in the molecule. The modified organoaluminum compound can be produced by a known method and is not particularly limited, but it is generally produced by reacting organoaluminum with water. This reaction is usually carried out in an inert hydrocarbon. As an inert hydrocarbon,
Aliphatic hydrocarbons such as pentane, hexane, heptane, cyclohexane, benzene, toluene, xylene, alicyclic hydrocarbons and aromatic hydrocarbons can be used, but the use of aliphatic or aromatic hydrocarbons is preferable.

The organoaluminum compound used to prepare the modified organoaluminum compound has the general formula R ¹ _n Al (OR ² ) _m
It is represented by X _3-mn . In the formula, R is a hydrocarbon group having 1 to 18 carbon atoms, preferably 1 to 12 such as an alkyl group, an alkenyl group, an aryl group and an aralkyl group, X is a hydrogen atom or a halogen atom, and n is 1 ≦ n ≦. Indicates an integer in the range of 3. Although any of the compounds represented by the above formula can be used, trialkylaluminum is preferably used. The alkyl group of trialkylaluminum may be any of a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, etc., but a methyl group is particularly preferable. The reaction ratio of water and the organoaluminum compound (water / Al molar ratio) is 0.25 / 1.
˜1.5 / 1, particularly preferably 0.5 / 1 to 1.2 / 1. The reaction temperature is generally -70 to 150 ° C, preferably -20 to 100 ° C. Reaction time is usually 5
It is selected from the range of minutes to 50 hours, preferably 10 minutes to 20 hours. As the water used in the reaction, in addition to ordinary water, water of crystallization contained in copper sulfate hydrate, aluminum sulfate hydrate and the like can be used.

As the boron compound as the component (4), a compound having at least one boron-carbon bond is preferably used, and examples thereof include borate and borane compounds. As the borate, the general formula [L ¹ ] ⁺ [BR ⁵ R ⁶ R
⁷ R ^{8] -} a compound represented by are preferred. In the formula, L ¹ is a compound capable of becoming a cation, and a Bronsted acid such as ammonium, anilium, phosphonium, or carbocation, methyl cation, ethyl cation, propyl cation, butyl cation, tropinium cation,
Examples thereof include benzyl cation and trityl cation. R ⁵ is an aromatic or substituted aromatic hydrocarbon group containing ⁵ to 20, preferably 6 to 16 carbon atoms, and the substituent is preferably an alkyl group or a halogen atom. R ^6, R ^7, R ⁸ is 5 to 20, preferably 6 to 16
An aromatic or substituted aromatic hydrocarbon group containing 1 carbon atom, a hydride group, a halide group, a hydrocarbyl group, the substituent is preferably an alkyl group or a halogen atom, and R ⁶ , R ⁷ , and R ⁸ are It may be the same as or different from R ⁵ .

Specific examples of the borate include tributylammonium tetra (o-fluorophenyl) borate, tributylammonium tetra (p-fluorophenyl) borate, tributylammonium tetra (m-).
Fluorophenyl) borate, tributylammonium tetra (3,5-difluorophenyl) borate, tributylammonium tetra (pentafluorophenyl)
Borate, dimethylanilinium tetra (o-fluorophenyl) borate, dimethylanilinium tetra (p
-Fluorophenyl) borate, dimethylanilinium tetra (m-fluorophenyl) borate, dimethylanilinium tetra (3,5-difluorophenyl) borate, dimethylanilinium tetra (pentafluorophenyl) borate, trityl tetra (o-fluorophenyl) ) Borate, trityl tetra (p-fluorophenyl) borate, trityl tetra (m-fluorophenyl) borate, trityl tetra (3,5-difluorophenyl) borate, trityl tetra (pentafluorophenyl) borate, tropinium tetra (o- Fluorophenyl) borate, tropinium tetra (p-fluorophenyl) borate, tropinium tetra (m-fluorophenyl) borate, tropinium tetra (3,5
-Difluorophenyl) borate, tropinium tetra (pentafluorophenyl) borate and the like. Among these, tributylammonium tetra (pentafluorophenyl) borate, dimethylanilinium tetra (pentafluorophenyl) borate, trityltetra (pentafluorophenyl) borate and tropinium tetra (pentafluorophenyl) borate are preferable.

The borane compound is represented by the general formula BR ⁹ R ¹⁰
The compound represented by R ¹¹ is preferred. In the formula, R ⁹ is the same as R ^{5 in} the general formula of the borate compound, and R ¹⁰ is R ⁶ and R ¹¹
Are the same as R ⁷ . R ¹⁰ and R ¹¹ may be the same as or different from R ⁹ . Specific examples of the borane compound include tri (o-fluorophenyl) borane, tri (p-fluorophenyl) borane, tri (m-fluorophenyl) borane, tri (3,5-difluorophenyl) borane, tri (penta). Fluorophenyl) borane and the like. Among these, tri (pentafluorophenyl) borane is preferable.

As the component (5), an inorganic carrier and / or
Alternatively, a particulate polymer carrier is used. The inorganic carrier may have any shape such as powder, granules, flakes, foil or fibrous shape as long as it retains its original shape at the stage of preparing the catalyst of the present invention.
In any case, the maximum length is usually 5 to 200 μm, and preferably 10 to 100 μm. The inorganic carrier is preferably porous, and usually has a surface area of 50 to 1000 m ² / g and a pore volume of 0.05 to ³ cm ³ .

As the inorganic carrier of the present invention, a carbon material,
Metal oxides, metal chlorides, metal carbonates or mixtures thereof can be used. Suitable metal oxides that can be used for the inorganic carrier include I to VII of the periodic table.
Examples thereof include single oxides or complex oxides of Group I metals, such as SiO ₂ , Al ₂ O ₃ , MgO, CaO, B ₂ O ₃ , TiO ₂ ,
ZrO ₂ , Fe ₂ O ₃ , SiO ₂ , Al ₂ O ₃ · MgO, Al ₂ O ₃ · C
aO, Al ₂ O ₃ · MgO · CaO, Al ₂ O ₃ · MgO · SiO ₂ , A
l ₂ O ₃ · CuO, Al ₂ O ₃ · Fe ₂ O ₃ , Al ₂ O ₃ · NiO, SiO
₂ · MgO and the like. It should be noted that the above formula expressed as an oxide does not represent a molecular formula but represents only the composition. Specific examples of metal chlorides include MgCl ₂ and CaC.
l _{2 and the} like are particularly preferable, and examples of the metal carbonate include magnesium carbonate, calcium carbonate, barium carbonate and the like. Examples of the carbonaceous material include carbon black and activated carbon. Any of the above inorganic carriers can be preferably used in the present invention, but metal oxides, silica, alumina and the like are particularly preferably used.

On the other hand, as the particle polymer carrier, either a thermoplastic resin or a thermosetting resin may be used as long as it does not melt and remains solid during catalyst preparation and polymerization reaction. Can be made and its particle size is 5 to 2
It is preferably 000 μm. Specifically, various polyolefins (preferably having 2 carbon atoms) represented by particulate ethylene polymers, ethylene / α-olefin copolymers, propylene polymers or copolymers, poly-1-butene, etc.
~ 12), polyester, polyamide, polyvinyl chloride, polymethyl methacrylate, polymethyl acrylate,
In addition to polystyrene and polynorbornene, various natural polymers and mixtures thereof can be used as the polymer carrier.

These inorganic carrier and / or particulate polymer carrier may be used as they are for catalyst preparation, or they may be used for catalyst preparation after being pretreated with an organic aluminum compound. Furthermore, regarding the inorganic carrier,
Component (5) after contacting with active hydrogen-containing compounds such as alcohols and aldehydes, electron-donating compounds such as esters and ethers, alkoxide group-containing compounds such as tetraalkoxysilicates, trialkoxyaluminums, transition metal tetraalkoxides, etc. The method used as is also preferably used.

The olefin polymerization catalyst used in the present invention is obtained by bringing the components (1) to (5) into contact with each other. The order of contacting these is not particularly limited, but preferably they can be prepared by any of the following methods. A. A method in which the components (1) to (3) are simultaneously contacted, then the component (4) is contacted, and then the component (5) is contacted. B. A method in which components (1) to (3) are contacted at the same time, while components (4) and (5) are contacted, and finally all are contacted. C. A method of contacting components (1) and (2), then component (3), then component (4), and finally component (5). D. A method of contacting the components (1) and (3), then the component (2), then the component (4), and finally the component (5). E. FIG. A method wherein components (1) and (2) are contacted, then component (3) is contacted, while components (4) and (5) are contacted and finally all are contacted. F. A method wherein components (1) and (3) are contacted, then component (2) is contacted, while components (4) and (5) are contacted and finally all are contacted. G. A method wherein components (2) and (3) are contacted, then component (1) is contacted, while components (4) and (5) are contacted and finally all are contacted. H. A method of contacting the components (1) and (5), then the component (2), then the component (3), and finally the component (4). I. A method of contacting the components (1) and (5), then the component (3), then the component (2), and finally the component (4).

The method of contacting these components is not particularly limited, but usually, in an inert atmosphere of nitrogen or argon, aromatic hydrocarbon such as benzene, toluene, xylene, ethylbenzene, heptane, hexane, decane,
A method of contacting each component in the presence of a liquid inert hydrocarbon such as an aliphatic or alicyclic hydrocarbon such as dodecane or cyclohexane is adopted. Contact is usually -100 ℃
To 200 ° C, preferably 0 ° C to 180 ° C, for 10 minutes to 50 hours, preferably 30 minutes to 30 hours.

The mixing ratio of the components (1) to (5) of the present invention is such that the content of the component (2) is usually 0.1 with respect to 1 mol of the component (1).
1 to 100 mol, preferably 1 to 50 mol, the component (3) is usually 0.1 to 100 mol, preferably 1 to 20 mol.
It is a molar ratio. Further, with respect to 1 mol of the component (1),
Component (4) is 1 to 10,000 as an aluminum atom.
The molar ratio is preferably 10 to 1,000 mol.
Further, the transition metal component of the component (1) is 0.0001 to 5 mmol, preferably 0.001 to 1 g of the component (5).
It is used in an amount of 0.5 mmol, more preferably 0.01 to 0.1 mmol.

When the components are brought into contact with each other in an inert hydrocarbon solvent, the hydrocarbon solvent is removed once,
It may be contacted with the next component, or may be directly contacted with the next component without removing the hydrocarbon solvent. Further, after the contact of all the components in the inert hydrocarbon solvent is completed, the produced catalyst can be directly subjected to the polymerization together with the solvent, and once taken out as a solid catalyst by a means such as precipitation and drying, it is used for the polymerization. You can also The solid catalyst obtained by the above method may be directly supplied to the polymerization reactor, or may be pretreated with olefins and then supplied to the polymerization reactor.

The polymerization reaction is carried out substantially in the gas phase. As the olefin polymerization conditions, the temperature is 20 to 300 ° C, preferably 40 to 200 ° C, and the pressure is normal pressure to 70 kgf / cm ² ·.
G, preferably ^{2 to} 60 kgf / cm ² · G.

Further, in the present invention, the reactor used for polymerizing or copolymerizing the olefin in a gas phase state includes substantially all fluidized bed systems operated in a gas-solid system and has a stirrer. Alternatively, it may be one that does not have it. During steady operation, the olefin and the solid catalyst component are constantly introduced into the reaction system, while the produced polymer particles are intermittently or continuously withdrawn from the reactor.

When the reaction is stopped, the supply of the olefin and the solid catalyst component is stopped, the pressure and temperature in the system are appropriately lowered, and the gaseous reaction terminator is introduced into the system. Carbon monoxide or carbon dioxide is used as the reaction terminator of the present invention. These can also be used by appropriately mixing them. The reaction terminator may be introduced into the reaction system together with an appropriate carrier gas, for example, a reactive gas such as olefin, or preferably a non-reactive carrier gas such as argon or helium, particularly preferably nitrogen. The amount of the terminating agent to be introduced must be at least 10 g or more per 1 kg of the catalyst, but it is difficult to strictly control the supply amount because it is gaseous. However, since it is necessary to completely deactivate the catalyst, it is usually desirable to introduce a large excess into the system. After confirming that the reaction has stopped, the excess reaction terminator is discharged out of the system. After discharging, the inside of the system is replaced with an inert gas such as nitrogen gas if necessary.
Since the reaction terminator is in a gaseous state, it can be easily discharged out of the system.

Even if the reaction terminator is supplied to the gas phase polymerization reactor, the effect of terminating the reaction is small unless it is brought into uniform and rapid contact with the catalyst particles in the reaction system. Therefore, the supply position and supply method of the reaction terminator are important. In order to effectively achieve the purpose, it is preferable to supply the reaction terminator to the lower part of the gas phase polymerization reactor. When the polymerization reaction is to be urgently stopped for various reasons during the operation of the circulating gas blower, a reaction terminator may be supplied into the circulating gas pipe below the gas phase polymerization reactor. Since the reaction terminator is mixed with the circulating gas and uniformly dispersed in the gas phase polymerization reactor, the polymerization reaction is quickly stopped. Even when the reaction in the gas phase polymerization reactor is to be stopped urgently due to the stop of the circulating gas blower, a reaction terminator may be supplied into the circulating gas pipe below the reactor. At this time, gas is urgently discharged from the top of the reactor, so that a pressure gradient occurs in the reactor, and as a result, the reaction terminator supplied from the lower part rises uniformly in the reactor. At this time, it is more preferable to entrain a carrier gas such as nitrogen together with the reaction terminator, because the dispersibility becomes good. The supply time of the reaction terminator is preferably within 5 minutes, more preferably within 1 minute.

Before restarting the operation, it is preferable to discharge the gaseous reaction terminator supplied for stopping the polymerization to the outside of the system as much as possible in advance. Therefore, the reaction system is purged with an inert gas to replace the gaseous reaction terminator with the inert gas. Nitrogen is preferred as the inert gas.
The above gas replacement can also be performed after an emergency stop of the reaction. The replacement method may be carried out by continuously circulating nitrogen in the system, or by pressurizing with nitrogen and then discharging the internal gas to the vent and repeating this. The concentration of the gaseous reaction terminator remaining in the system is 10 ppm or less, preferably 1 ppm or less, and more preferably 0.1 ppm or less at normal pressure after purging or discharging to the vent.

Upon restarting the operation, all the polymer remaining in the system is discharged out of the system. Thereafter, the new polymer particles are charged into the polymerization reactor. The nitrogen is circulated at a pressure of 0 to 10 kgf / cm ² · G, preferably 3 to 6 kgf / cm ² · G. The temperature of nitrogen is usually 10 to 1 like the polymerization temperature.
The temperature is 00 ° C, preferably 40 to 90 ° C. After that, the polymerization can be started according to the procedure of a normal operation starting operation. That is, the polymerization is restarted by introducing the olefin gas and supplying the catalyst.

[0037]

BEST MODE FOR CARRYING OUT THE INVENTION In the operation of a polyolefin gas-phase polymerization reactor using a catalyst obtained by contacting specific 5 components, a group consisting of water, alcohol, molecular oxygen, carbon dioxide and carbon monoxide is used. By supplying any of the selected compounds, the olefin polymerization reaction can be stopped in a short time.

[0038]

【Example】

<Catalyst preparation example> Purified toluene 60 m in a 300 ml eggplant type flask equipped with an electromagnetic induction stirrer under a nitrogen atmosphere.
l, then tetrapropoxy zirconium 0.6
After adding 5 g and 1.85 g of indene and stirring at room temperature for 30 minutes, the mixture was kept at 0 ° C. and triethylaluminum (Al
Et ₃₎ 1.84 g was added dropwise spending 30 minutes and stirred for 24 hours in the After completion of the dropwise addition at room temperature. Next, to this solution, a solution of methylaluminoxane in toluene (concentration 1 mmol / ml) 2
After adding 00 ml and reacting at room temperature for 1 hour, it was left to stand at room temperature for one day. This solution is referred to as A solution. Next, in a nitrogen atmosphere, in a 500 ml three-necked flask equipped with a stirrer, 50 g of silica (grade # 952, surface area 300 m ² / g; manufactured by Fuji Devison Chemical Co., Ltd.) preliminarily baked at 600 ° C. for 5 hours was put, Add the whole amount of the solution A,
The mixture was stirred at room temperature for 2 hours. Then, nitrogen blowing was performed to remove the solvent to obtain a solid catalyst.

<Example> A fluidized bed reactor having a diameter of 25 cm shown in FIG. 1 was used. The fluidized bed reactor 1 comprises an upper space area 2 and a fluidized bed area 3, and a gas dispersion plate 4 is provided at the bottom of the fluidized bed area 3. Preliminarily dried linear low-density polyethylene with an average particle size of 650 μm 17 kg
As a seed polymer was charged into the fluidized bed reactor 1. Next, the inside of the reaction system is pressurized to 5 kgf / cm ² · G with the nitrogen gas supplied from the nitrogen supply pipe 8, and the gas in the system is supplied to the fluidized bed reactor 1, the gas circulation pipe 10, and the blower 11 using the blower 11. And a flow rate of 88 m ³ through the route consisting of the cooler 12
The temperature in the system was kept at 75 ° C. by circulating the gas at a rate of / hr and adjusting the temperature of the circulating gas. Ethylene and butene-1 are supplied from the olefin supply pipe 5, and ethylene in the gas phase /
The amount of each gas was adjusted so that the butene-1 ratio (molar ratio, the same applies hereinafter) = 1 / 0.07 and the nitrogen concentration 30 mol%, and the total pressure was maintained at 19 kgf / cm ² · G. The solid catalyst obtained in the above catalyst preparation example was fed through the catalyst feed pipe 6 at a rate of 1.0 g / hr to start the polymerization reaction. In addition, in order to charge the catalyst, nitrogen is supplied from the catalyst charging nitrogen supply pipe 15. The reaction reached a steady state after 12 hours, and then the operation continued smoothly. The production rate of the ethylene-butene-1 copolymer discharged through the polymer discharge valves 13 and 14 was 3.0 kg / hr, and its property was MFR 1.
It was 9 g / 10 min and the density was 0.9208 g / cm ³ . The appearance was white, and the particles were uniform particles having an average particle size of 650 μm.

Next, 28 g of carbon dioxide was supplied into the circulating gas through the reaction stopper supply pipe 7 in order to perform an emergency stop of the polymerization reaction. Immediately after that, the temperature of the circulating gas, which was controlled so as to maintain the system at a constant temperature, rapidly increased, the rise of the differential pressure in the fluidized bed was also stopped, and the termination of the polymerization reaction was confirmed. Circulating gas is discharged from the vent pipe 9 and the pressure in the system is reduced to 6 kgf / cm ² · G in 20 minutes, and the temperature is raised to 5
The temperature was lowered to 0 ° C. While the gas in the system was discharged from the vent pipe 9 at a flow rate of 16 m ³ / hr using a blower 11, nitrogen was introduced through the nitrogen supply pipe 8 and the pressure was maintained at 6 kgf / cm ² · G. After 5 hours, the polymer particle discharge valves 13 and 14 were operated to discharge the entire amount of the polymer particles remaining in the fluidized bed reactor 1 out of the system. Then, the blower 11 was stopped, and the gas was discharged from the vent pipe 9 until the pressure in the system reached normal pressure. Subsequently, the operation of increasing the pressure in the system to 5 kgf / cm ² · G with nitrogen and then releasing the pressure to normal pressure was repeated 3 times to purge carbon dioxide gas.

Thereafter, the average particle size of 650 μm, which has been dried in advance, is used.
17 kg of linear low-density polyethylene of Example 1 was charged to the fluidized bed reactor 1 as a seed polymer. Then, the pressure in the reaction system was increased to 5 kgf / cm ² · G with nitrogen gas, and the gas in the system was formed using the blower 11 by the fluidized bed reactor 1, the gas circulation pipe 10, the blower 11 and the cooler 12. Flow rate through 88
It was circulated at m ³ / hr and maintained at 75 ° C. by adjusting the temperature of the circulating gas. Ethylene / butene-1 ratio in the gas phase = 1 / 0.0
The amount of each gas was adjusted to 7 and the nitrogen concentration of 30 mol%, and the total pressure was kept at 19 kgf / cm ² · G. The solid catalyst obtained in the above catalyst preparation example was supplied from the catalyst supply pipe 6 at a rate of 0.9 g / hr to start the polymerization reaction. The reaction reached a steady state after 12 hours, and the operation continued smoothly thereafter. The production rate of ethylene / butene-1 copolymer discharged through the polymer particle discharge valves 13 and 14 is 2.8 kg / hr.
And its properties are MFR 1.8g / 10min and density 0.
It was 9210 g / cm ³ . The appearance was white, and the particles were uniform particles having an average particle size of 650 μm.

Comparative Example The same procedure as in Example 1 was carried out except that carbon dioxide gas was not supplied when the polymerization reaction was stopped urgently. That is, only the supply of the solid catalyst was stopped without supplying carbon dioxide. However, the polymerization reaction did not stop easily, and it took about 8 hours until the polymerization reaction rate in the steady state decreased to 1/2.

[0043]

INDUSTRIAL APPLICABILITY In the operation of a polyolefin gas phase polymerization reactor using a specific catalyst, by supplying any compound selected from the group consisting of water, alcohol, molecular oxygen, carbon dioxide and carbon monoxide. It is possible to stop the olefin polymerization reaction in a short time.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a gas phase polymerization reaction device.

[Explanation of symbols]

 1 Fluidized Bed Reactor 2 Upper Space Area 3 Fluidized Bed Area 4 Gas Dispersion Plate 5 Olefin Supply Pipe 6 Catalyst Supply Pipe 7 Reaction Stopper Supply Pipe 8 Nitrogen Supply Pipe 9 Vent Pipe 10 Gas Circulation Pipe 11 Blower 12 Cooler 13, 14 Polymer particle discharge valve 15 Nitrogen supply pipe for catalyst loading

Claims (2)

[Claims] 1. Water and alcohol are fed to a reactor for constantly polymerizing or copolymerizing an olefin in a gas phase in the presence of a catalyst obtained by contacting the following components (1) to (5) with each other. A method for urgently stopping an olefin polymerization reaction, which comprises introducing a compound selected from the group consisting of molecular oxygen, carbon dioxide and carbon monoxide to stop the olefin polymerization reaction in a short period of time, (1 )
A compound containing a Group IVB metal of the periodic table, (2) a compound containing any one of Group I to III metals of the periodic table, (3)
An organic cyclic compound having two or more conjugated double bonds, (4)
A modified organoaluminum compound and / or a boron compound having an Al-O-Al bond, (5) an inorganic compound carrier and / or a particulate polymer carrier. 2. The olefin polymerization reaction according to claim 1, wherein the olefin polymerization reaction is carried out in the presence of a catalyst obtained by bringing the following components (1) to (5) into contact with each other. Emergency stop method, (1) General formula Me
¹ (OR ¹ ) _p R ² _q X ¹ _4-pq (R ¹ and R ² are hydrocarbon groups, X ¹ is a halogen atom, Me ¹ is Ti, Zr or Hf, 0 ≦ p ≦
4, 0 ≦ q ≦ 4, and 0 ≦ p + q ≦ 4), (2) the general formula Me ² (OR ³ ) _m R ⁴ _n X ² _3-mn (wherein
R ³ and R ⁴ are hydrocarbon groups, X ² is a hydrogen atom or a halogen atom, Me ² is a Group III metal of the periodic table, 0 ≦ m ≦ 3, 0 ≦
a compound represented by n ≦ 3 and 0 ≦ m + n ≦ 3),
(3) an organic cyclic compound having two or more conjugated double bonds,
(4) A modified organoaluminum compound having an Al-O-Al bond and / or a boron compound, (5) an inorganic compound carrier and / or a particulate polymer carrier.