KR20170036233A

KR20170036233A - Catalyst system for olefin oligomerization, and method for olefin oligomerization using the same

Info

Publication number: KR20170036233A
Application number: KR1020150135138A
Authority: KR
Inventors: 김태진; 김희영; 신민재; 윤승웅
Original assignee: 롯데케미칼 주식회사
Priority date: 2015-09-24
Filing date: 2015-09-24
Publication date: 2017-04-03
Also published as: KR101832448B1

Abstract

The present invention relates to a catalyst system for olefin oligomerization, and to an olefin oligomerization method using the same. According to the present invention, the catalyst system for oligomerization of olefin is highly selective to 1-hexene while having outstanding catalytic activities, thereby making the production of alpha-olefin more efficient. To this end, the catalyst system comprises: a ligand compound represented by chemical formula 1; a transition metal source; and a cocatalyst including at least two types of aluminum alkyl compounds.

Description

TECHNICAL FIELD The present invention relates to a catalyst system for olefin oligomerization, and a method for olefin oligomerization using the catalyst system for olefin oligomerization.

The present invention relates to a catalyst system for olefin oligomerization and an olefin oligomerization method using the same.

Linear alpha-olefins are widely used commercially as important materials for comonomers, detergents, lubricants, and plasticizers. Especially, 1-hexene and 1-octene are used in the production of linear low density polyethylene (LLDPE) It is widely used as a comonomer for controlling density.

Since alpha-olefins vary in application field or market size depending on the type of olefin, the technology capable of selectively producing a specific olefin is of great commercial significance. Recently, selective ethylene oligomerization has been used to produce 1-hexene or 1 - octene catalysts have been studied extensively.

Specifically, U.S. Patent No. 7361623 discloses a catalyst system for producing 1-hexene and 1-octene using chromium as a central metal, but the catalyst system can not consistently maintain the reaction activity depending on the reaction time, Is greatly reduced.

Korean Patent No. 10-0435513 discloses a catalyst system for the production of 1-hexene using chromium as a central metal. However, since the performance of the catalyst is exhibited under conditions of high temperature and high pressure, There is a limit.

Accordingly, there is a continuing need for a continuously increasing mass-increasing reaction activity and a high selectivity during the reaction in the production of alpha-olefins such as 1-octene or 1-hexene.

U.S. Patent No. 7361623 Korea Patent No. 10-0435513

The present invention provides a catalyst system for olefin oligomerization capable of oligomerization of olefins with high catalytic activity and selectivity, and an olefin oligomerization method using the same.

The present invention relates to a ligand compound represented by the following general formula (1): A transition metal source; And a cocatalyst comprising two or more alkylaluminum compounds. The present invention also provides a catalyst system for olefin oligomerization.

The present invention also provides an olefin oligomerization process comprising the step of mass-reacting olefins in the presence of the catalyst system for olefin oligomerization.

Hereinafter, a catalyst system for olefin oligomerization and a method for olefin oligomerization according to specific embodiments of the present invention will be described in detail.

The term " olefin oligomerization " used in the present invention means olefin polymerization. It is called "trimerization" and "tetramerization" according to the number of olefins to be polymerized, and is collectively referred to as "multimerization". In particular, the present invention means that 1-hexene is selectively produced from ethylene.

And, alkyl means a monovalent functional group derived from an alkane.

In addition, aryl means a monovalent functional group derived from arene, alkylaryl means an aryl group having at least one linear or branched alkyl group introduced therein, and arylakyl means Means a linear or branched alkyl group having at least one aryl group introduced thereto.

In addition, cycloalkyl means a monovalent functional group derived from cycloalkane, alkoxy means a monovalent functional group in which a straight-chain or branched-chain alkyl group is bonded to oxygen, and aryloxy refers to an aryloxy group in which an aryl group is oxygen &Lt; / RTI >

Further, alkylsilyl and arylsilyl mean a silyl group bonded with an alkyl group and an aryl group, respectively.

In addition, alkylene means a divalent functional group derived from an alkane, alkenylene means a divalent functional group derived from an alkene, arylene means an arylene, refers to a divalent functional group derived from arene, wherein the alkylarylene group means an arylene group in which one or more alkyl groups are substituted, and the allylalkylene group means an alkylene group in which at least one allyl group is substituted.

According to one embodiment of the present invention, a ligand compound represented by the following general formula (1); A transition metal source; And a cocatalyst comprising at least two alkyl aluminum compounds, can be provided:

[Chemical Formula 1]

In Formula 1,

E ₁ to E ₄ each independently represent an element selected from the group consisting of boron (B), carbon (C), nitrogen (N), oxygen (O), silicon (Si), phosphorus (P) And at least one of E ₁ to E ₄ is an element selected from the group consisting of boron (B), nitrogen (N), oxygen (O), silicon (Si), phosphorus (P) ,

R ₁ to R ₁₀ are each independently selected from the group consisting of hydrogen, a hydroxyl group, an alkyl (Alky) group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, A halogenoalkyl group having 6 to 40 carbon atoms, an arylalkyl group having 6 to 40 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms, an arylsilyl group having 6 to 20 carbon atoms, an alkylaryl group having 7 to 20 carbon atoms Alkylaryl group, an alkoxy group having 1 to 20 carbon atoms, an alkyloxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a halogen group, ) Group,

n and m are integers of 0 to 20,

p and q are integers of 0 to 5;

The present inventors have found that a catalyst system for olefin oligomerization comprising a ligand compound having the above specific structure and a cocatalyst containing a transition metal source and two or more alkylaluminum compounds can be suitably controlled by electronically , It is possible to control oligomerization of olefins with high catalytic activity and selectivity because the steric environment can be easily controlled.

In particular, the ligand compound is a cyclic compound in which a functional group which is connected to a ring or to a ring includes boron (B), nitrogen (N), oxygen (O), silicon (Si), phosphorus (P) Due to these structural features, the ligand compounds can be applied to oligomerization catalyst systems of olefins to exhibit high oligomerization reaction activity, and in particular exhibit high selectivity for 1-hexene . This is presumably due to the interaction between each adjacent chromium active point.

In the ligand compound represented by the above formula (1), E ₁ to E ₄ are independently selected from the group consisting of boron (B), carbon (C), nitrogen (N), oxygen (O), silicon (Si) , And sulfur (S). In the ligand compound, in particular, when the above-mentioned hetero element enriched in electrons is introduced at the E ₁ to E ₄ positions, the stability when the center metal becomes a cation can be improved. Accordingly, the catalyst system for olefin oligomerization containing such a ligand compound can exhibit high activity in the oligomerization reaction.

In particular, at least one of E ₁ to E ₄ is an element selected from the group consisting of boron (B), nitrogen (N), oxygen (O), silicon (Si), phosphorus (P) And more preferably at least one of the above E ₁ to E ₄ may each independently be nitrogen (N) or oxygen (O).

In the above formula (1), R ₁ to R ₁₀ are each independently selected from the group consisting of hydrogen, a hydroxyl group, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms , A haloalkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 40 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms, an arylsilyl group having 6 to 20 carbon atoms, An alkoxy group having 1 to 20 carbon atoms, an alkyloxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a halogen atom, Or an amino group and the aryl group is selected from the group consisting of phenyl, biphenyl, triphenyl, triphenylene, naphthalenyl, anthracenyl, phenalenyl, phenanthrenyl, fluorenyl, pyrenyl, Aromatic hydrocarbon functional groups such as perylenyl, azulenyl, dibenzothiophenyl, dibenzofuranyl, di Benzothiophenyl, benzoselenophenyl, carbazonyl, indolocarbazolyl, pyridylindolinyl, pyrrolodipyridinyl, pyrazolyl, imidazolyl, imidazolyl, imidazolyl, Wherein the heterocyclic ring is selected from the group consisting of pyridyl, thiazolyl, oxazolyl, thiazolyl, oxadiazolinyl, oxatriazolyl, dioxazolyl, thiadiazolyl, pyridyl, pyridazinyl, pyrimidyl, pyrazinyl, Benzoxazolyl, quinolinyl, quinazolinyl, quinazolyl, quinazolinyl, quinazolinyl, quinazolinyl, quinazolinyl, quinazolinyl, quinazolinyl, indolinyl, Thienyl, thiophene, thienyl, thienyl, thienyl, thienyl, thienyl, thienyl, thienyl, thienyl, thienyl, thienyl, Aromatic dicarboxylic acids such as nordipyridyl benzoselenophenopyridyl and selenophenodipyridyl A cyclic functional group, or the like.

R ₁ to R ₁₀ in Formula 1 are hydrogen, a hydroxyl group, an amino group, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, or an aryl group, It is possible to produce a polyolefin having a selectivity.

Specific examples of such ligand compounds are as follows:

,

,

,

The transition metal source in the catalyst system for olefin oligomerization according to one embodiment of the present invention serves as a main catalyst and includes a transition metal of Group 4 to Group 12. Specifically, the transition metal itself or an organic compound containing the transition metal have.

The transition metal source may comprise a chromium compound.

The chromium compound may be a chromium metal or an organic compound containing chromium. Specifically, the chromium compound may be chromium, chromium (III) acetylacetonate, chromium tris (tetrahexyl) chromium trichloride, chromium (III) 2-ethylhexanoate, or a mixture of two or more thereof.

In addition, the catalyst system for oligomerization of olefins includes two or more alkylaluminum compounds as cocatalysts in addition to the ligand and the transition metal source. When the alkylaluminum compound is used as described above, the alkylaluminum High catalytic activity and economic efficiency can be secured as compared with the case of using noxious acid.

Examples of the alkyl aluminum compound include triethyl aluminum, tripropyl aluminum, tributyl aluminum, diethyl aluminum chloride, diethyl aluminum bromide, diethyl aluminum ethoxide, diethyl aluminum phenoxide, ethyl aluminum dichloride, Or a mixture thereof may be used, and preferably two or more selected from the group consisting of triethylaluminum, ethylaluminum dichloride and ethylaluminum sesquichloride.

Particularly, as the two or more alkylaluminum compounds included as the promoter, it is preferable to use an alkylaluminum compound containing no halogen element and an alkylaluminum compound containing a halogen element in order to increase the catalytic activity Do. That is, examples of the above-mentioned specific alkylaluminum compounds include alkylaluminum compounds containing no halogen element such as triethylaluminum, tripropylaluminum, tributylaluminum and the like, and alkylaluminum compounds containing no ethylaluminum dichloride, ethylaluminum sesquichloride, diethylaluminum Chloride and the like may be mixed and used.

More specifically, the non-covalent electron pair of the halogen element of the alkyl aluminum compound including the halogen can protect the transition metal lacking electrons, for example, chromium. Therefore, alkyl aluminum containing no halogen as a cocatalyst It is possible to provide a catalyst system having increased catalytic activity, such as when only the compound is used or when an alkylaluminoxane compound is used.

The molar ratio of the ligand compound: transition metal source: cocatalyst is about 0.5: 1: 1 to about 10: 1: 10,000 for the olefin oligomerization catalyst system to increase the selectivity for the linear alpha olefin and increase the mass- And preferably from about 0.5: 1: 100 to about 5: 1: 3,000. However, the present invention is not limited thereto.

According to another embodiment of the present invention, there is provided a process for preparing an olefin oligomer comprising the step of mass-reacting an olefin in the presence of the catalyst system for olefin oligomerization. The use of the olefin oligomerization catalyst system of one embodiment can provide a method of oligomerization of olefins having improved activity and selectivity of the reaction. At this time, the olefin is preferably ethylene.

The olefin oligomerization according to the present invention can be carried out in the presence of an inert solvent in the presence or absence of an inert solvent using a conventional apparatus and contact technique with the catalyst system for olefin oligomerization, a slurry reaction in which the catalyst system is partially or completely dissolved , Two-phase liquid / liquid reactions, or bulk-phase or gas-phase reactions in which product olefins act as the main medium, and a homogeneous liquid phase reaction is preferred.

The olefin oligomerization reaction can be carried out in any inert solvent that does not react with the catalyst compound and the activator. Suitable inert solvents include, but are not limited to, benzene, toluene, xylene, cumene, heptane, cyclohexane, methylcyclohexane, methylcyclopentane, hexane, pentane, butane and isobutane. At this time, the solvent can be used by removing a small amount of water or air acting as a catalyst poison by treating with a small amount of alkylaluminum.

The olefin oligomerization reaction may be carried out at a temperature of from about 0 ° C to about 200 ° C, preferably from about 30 ° C to about 150 ° C. In addition, the olefin oligomerization reaction can be carried out at a pressure of from about 1 bar to about 300 bar, preferably from about 10 bar to about 100 bar.

The use of a catalyst system comprising a ligand compound according to the present invention enables oligomerization of ethylene with high catalytic activity and selectivity compared to existing catalyst systems, and a more stable polymerization reaction is possible because of excellent catalyst stability.

The invention will be described in more detail in the following examples. However, the following examples are illustrative of the present invention, and the present invention is not limited by the following examples.

All synthetic reactions were conducted under an inert atmosphere such as nitrogen or argon, using standard Schlenk technology and Glove Box technology. In the following examples, the ligand and the chromium reagent were purchased from Sigma-Aldrich and used without purification.

The ligand compounds used in the following examples are as follows:

Examples and Comparative Examples: Preparation of a catalyst system for olefin oligomerization

Example 1

30 mL (21.3 mmol) of chromium (III) 2-ethylhexanoate was dissolved in anhydrous toluene and the ligand (63.8 mmol) was added. Then, in a separate vessel, ethyl aluminum dichloride (85.1 mmol) and triethyl aluminum (319 mmol) were mixed together. The ethylaluminum dichloride and triethylaluminum solutions were then slowly added to the chromium / ligand solution. Then, the dark yellowish brown solution was stirred for 5 minutes, and then the solvent was removed under vacuum. The remaining oily liquid was diluted with cyclohexane to 150 mL and the solution was filtered to remove the black precipitate from the filtrate containing the catalyst system and diluted with toluene to a volume of 250 mL to prepare a catalyst system for olefin oligomerization.

Example 2

A catalyst system for olefin oligomerization was prepared in the same manner as in Example 1 except that 50 ml of anhydrous cyclohexane was used instead of anhydrous toluene.

Example 3

A catalyst system for olefin oligomerization was prepared in the same manner as in Example 1 except that ethyl aluminum sesquichloride (85.1 mmol) was used instead of ethyl aluminum dichloride.

Comparative Example 1

Except that 9.0 mmol of methylaluminoxane (MAO) (10 wt% in toluene, Albermale) was used instead of ethylaluminum dichloride (85.1 mmol) and triethylaluminum (319 mmol) as cocatalysts in the same manner as in Example 1 To prepare a catalyst system for olefin oligomerization.

The results of the production of 1-hexene using the catalyst prepared in each Example and the catalyst of Comparative Example are shown in Table 1 below.

Experimental Example: Olefin oligomerization

A 2 L stainless steel reactor was charged with nitrogen, 1 L of reaction solvent was added, 3 mL of triethylaluminum was added, 10 bar of ethylene was charged, and the temperature was raised to 90 캜. Then, the catalyst solution prepared in Examples 1 to 3 or Comparative Example 1 was charged into a reactor, filled with ethylene at 35 bar, and stirred at a stirring speed of 500 rpm. After one hour, the ethylene feed to the reactor was stopped, the stirring was stopped to stop the reaction and the reactor was cooled to below 10 < 0 > C. After the excess ethylene was discharged from the reactor, ethanol containing 10 vol% hydrochloric acid was injected into the liquid contained in the reactor. A small amount of organic layer sample was passed over silica gel, dried and analyzed by GC-FID. The remaining organic layer was filtered to separate the solid wax / polymer product. These solid products were dried in an oven at 80 DEG C for 8 hours and then weighed to give polyethylene.

The results of the production of 1-hexene using the catalysts prepared in Examples and Comparative Examples are shown in Table 1 below.

catalyst Reaction solvent 1-hexene
(wt%) activation PE (g) Example 1 Cyclohexane 97.2 4.5 2.8 Example 1 toluene 99.1 5.2 0.9 Example 2 Cyclohexane 98.3 4.5 1.7 Example 2 toluene 99.2 5.7 0.8 Example 3 Cyclohexane 97.6 4.1 2.4 Example 3 toluene 99.1 4.5 0.9 Comparative Example 1 Cyclohexane 98.1 1.7 1.9

* Catalytic activity unit: (Kg of Product / mmol of Cat)

As shown in Table 1, the experimental examples using the catalyst system of the embodiment including two kinds of alkyl aluminum compounds as cocatalysts showed higher catalytic activity than those of the catalyst systems of comparative examples containing methyl aluminoxane as a cocatalyst , And less polyethylene (by-product).

Claims

A ligand compound represented by the following formula (1);
A transition metal source; And
A cocatalyst comprising at least two alkyl aluminum compounds,
[Chemical Formula 1]

In Formula 1,
E ₁ to E ₄ each independently represent an element selected from the group consisting of boron (B), carbon (C), nitrogen (N), oxygen (O), silicon (Si), phosphorus (P) And at least one of E ₁ to E ₄ is an element selected from the group consisting of boron (B), nitrogen (N), oxygen (O), silicon (Si), phosphorus (P) ,
R ₁ to R ₁₀ are each independently selected from the group consisting of hydrogen, a hydroxyl group, an alkyl (Alky) group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, A halogenoalkyl group having 6 to 40 carbon atoms, an arylalkyl group having 6 to 40 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms, an arylsilyl group having 6 to 20 carbon atoms, an alkylaryl group having 7 to 20 carbon atoms Alkylaryl group, an alkoxy group having 1 to 20 carbon atoms, an alkyloxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a halogen group, ) Group,
n and m are integers of 0 to 20,
p and q are integers of 0 to 5;

The method according to claim 1,
At least one or more of E ₁ to E ₄ in Formula 1 are each independently nitrogen (N) or oxygen (O).

The method according to claim 1,
R ₁ to R ₁₀ in Formula 1 are selected from the group consisting of hydrogen, a hydroxyl group, an amino group, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, and an aryl group.

The olefin oligomerization catalyst system according to claim 1, wherein the ligand compound is selected from the group consisting of the following structural formulas:

,

,

, And

The method according to claim 1,
Wherein the transition metal source is at least one selected from the group consisting of chromium, chromium (III) acetylacetonate, chromium tristate tetrafluoride, and chromium (III) 2-ethylhexanoate.

The method according to claim 1,
The alkyl aluminum compound is preferably selected from the group consisting of triethylaluminum, tripropylaluminum, tributylaluminum, diethylaluminum chloride, diethylaluminum bromide, diethylaluminum ethoxide, diethylaluminum phenoxide, ethylaluminum dichloride and ethylaluminum sesquichloride Lt; RTI ID = 0.0 > oligomerization < / RTI >

The method according to claim 1,
Wherein the cocatalyst comprises an alkyl aluminum compound containing no halogen element and an alkyl aluminum compound containing a halogen element.

The method according to claim 1,
Wherein the cocatalyst comprises at least two alkylaluminum compounds selected from the group consisting of triethylaluminum, ethylaluminum dichloride and ethylaluminum sesquichloride.

The method according to claim 1,
Wherein the molar ratio of the ligand compound: transition metal source: cocatalyst is from 0.5: 1: 1 to 10: 1: 10,000.

A process for the oligomerization of olefins comprising subjecting the olefins to a multiplication reaction in the presence of the catalyst system for olefin oligomerization of claim 1.

11. The method of claim 10,
Wherein the oligomerization reaction temperature is 0 to 200 < 0 > C.