AU624652B2 - A process for preparing linear alpha-olefins - Google Patents

Description

S F Ref: 113326 FORM COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952 COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE: Class Int Class Complete Specification Lodged: Accepted: Publ i shed: Priority: Related Art: Name and Address of Applicant: Idemitsu Petrochemical Company Limited 1-1, Marunouchi 3-chome Chiyoda-ku Tokyo

JAPAN

Spruson Ferguson, Patent Attorneys Level 33 St Martins Tower, 31 Market Street Sydney, New South Wales, 2000, Australia i jj

I

j Address for Service: Complete Specification for the invention entitled: V 11 A Process for Preparing Linear a-0lefiis The following statement is a full description of this invention, including the best method of performing it known to me/us 5845/3

ABSTRACT

The present invention provides a process for preparing a linear (<-olefin having from 6 to 18 carbon atoms comprising polymerizing ethylene or an ethylene containing O(-olefin in the presence of a catalyst consisting of a zirconium halide, an organoaluminum compound and a Lewis base in an inert solvent and stopping the polymerization by adding a catalyst deactivating agent to the resulting reaction mixture, wherein said catalyst contains a zirconium component comprising a zirconium halide represented by the formula ZrXaA4-a (I) S wherein X and A may be the same or different and each represents a chlorine atom, a bromine atom or an iodine atom and a is 0 or 0 0 an integer of 1 to 4; an aluminum component comprising: an alkylaluminum compound represented by the formula (II): AIR1 1 5Q 1 .5 (II) wherein R 1 represents an alkyl group having from 1 to 20 carbon atoms, and Q1 represents a chlorine atom, a bromine atom or S an iodine atom and R 1 and Q 1 may be the same or different respectively, and said formula (II) may also be represented by Al 2 R13Q 1 3 and an alkylaluminum compound represented by the Sformula (III):

AIR

2 bQ 2 3-b (III) wherein R 2 and Q 2 which may be the same or different,respectively, have the same meanings as R1 and Q 1 above and b is an integer of 1 to 3, said catalyst being mixed at a molar ratio of said zirconium componont and aluminum component ({AIR 1 1 5

Q

1 1 5 AlR 2 bQ 2 3-b /ZrXaA4a) of from 3 to 15 and at a molar ratio of 1 II I the components represented by the formulae (II) and (III) (AIR11.5Q 1 1.5/AlR 2 bQ 2 3-b) of from 2 to 10; and said catalyst further contains at least one Lewis base selected from the group consisting of thiophene, methyl disulfide, thiourea, triphenylphosphine and trioctylphosphine and said inert solvent is at least one solvent selected from the group consi: .ing of naphthenic solvents and aromatic hydrocarbon solvents.

i7 ,i i| A PROCESS FOR PREPARING LINEARC(-OLEFINS FIELD OF THE INVENTION The present invention relates to a process for preparing linear c0-olefins. More particularly, the present invention relates to a process for preparing CO-olefins by oligomerizing ethylene according to which not only linear q(i\ olefins can be prepared in high purities with by-producing i wax in small amounts but also long production run is possible.

BACKGROUND OF THE INVENTION O(-Olefins are useful as they are as a comonomer for modification in the field of preparing polyolefins or as a plasticizer or a surface active agent after they are alcoholized.

i| Generally, such linealr -olefins are prepared by oligomerizing ethylene in the presence of a catalyst. As for the catalyst there is known, for example, a binary catalyst which consists of titanium tetrachloride and ethylaluminium dichloride. Also, a process for increasing the yield and selectivity of (6-olefins using a catalyst which consists of a third component in addition to the abovedescribed binary catalyst composition is known.

On the other hand, binary catalysts with increased activities have recently been proposed which comprises zirconium (Zr) instead of the above-d!s-ribed titanium compound. For example, Japanese Patent Application Laid- Open Nos. 109428/83, 201729/83 and 113138/83 and Japanese Patent Publication No. 30042/75 disclose binary catalysts which consist of a Zr compound and an Al compound.

16- However, proccsses for the oligomerization of ethylene using the above-described binary catalysts comprising Zr have caused various problems. For example, final products contain wax fraction in large amounts or the yield of oligomers having a small number of carbon atoms, those having about 4 carbon atoms, is increased and the purity of the (X-olefins obtained is very low. Further, long continuous operation of production unit is difficult since wax fraction is formed in a large amount or for other reasons.

U. S. Patent 4,486,615 discloses a catalyst composition consisting of a binary catalyst composed of a Zr i compound and an Al compound and a Lewis base such as a tertiary amine, a secondary amine, an ether, a phosphine oxide, an alkyl phosphate, an aryl phosphate, a sulfoxide, etc. which is added as a third component in order to increase the activity of the binary catalyst.

However, although it is described in U. S. Patent 4,486,615 that a linear C-olefin having high purity as high as 99.5% can be prepared using the catalyst composition containing triethylamine as the most preferred example of the Lewis base it has been confirmed by the present inventors Ithat use of the catalyst compositions containing Lewis bases J referred to in U. S. Patent 4,486,615 other than triethylamine results in the preparation of linear (-olefins having low purity and that a large amount of the above-described ternary catalyst containing triethylamine is used in U. S. Patent 4,486,615.

2- 2_ 3 SUMMARY OF THE INVENTION An object of the present invention is to obviate the defects of the i conventional processes and to provide a process for preparing a linear ca-olefin by oligomerizing ethylene according to which the medium fraction containing from about 6 to 20 carbon atoms can be obtained in a high yield and the purity of the a-olefin obtained is high with forming a small amount of wax fraction, thus enabling long production runs.

Another object of the present invention is to provide a process for preparing a linear a-olefin by oligomerizing ethylene according to which linear a-olefins containing low content of halogen derived from i the catalyst used can be prepared in high purity.

The present invention provides a process for preparing a linear I a-olefin having from 6 to 18 carbon atoms comprising polymerizing i ethylene or an ethylene containing a-olefin in the presence of a catalyst consisting of a zirconium halide, an organoaluminum compound and a Lewis base in an inert solvent which comprises at least 75% by weight of a naphthenic hydrocarbon solvent and stopping the polymerization by Sadding a catalyst deactivating agent to the resulting reaction mixture, wherein said catalyst contains a zirconium component comprising a i 20 zirconium halide represented by the formula ZrXaA a

(I)

i wherein X and A may be the same or different and each represents a chlorine atom, a bromine atom or an iodine atom and a is 0 or an integer of 1 to 4; an aluminum component comprising: an alkylaluminium compound represented by the formula (II): wherein R 1 represents an alkyl group having from 1 to 20 carbon atoms, and Q -represents a chlorine atom, a bromine atom or an iodine atom and R and Q may be the same or different, respectively and said formula 1 S/1777R vt4V U) "NrO' 7 1 -4- I 1 (II) may also be represented by A1 2

R

3 3 and an alkylaluminium compound represented by the formula (III): b 3-b

(III)

wherein R 2 and Q2 which may be the same or different respectively, have the same meanings as R 1 and Q above and b is an integer of 1 to 3, said catalyst being mixed at a molar ratio of said zirconium component 1 1 22 and aluminium component ({A 1 5Q 1. +A 1 RbQ 3 ZrXaA4-a) of from 3 to 15 and at a molar ratio of the components represented by the formulae (II) and (III) (AIR .5 Q 1/ AIR Q of from 2 to 10; and said catalyst further contains at least one Lewis base selected from the group consisting of thiophene, methyl disulfide, thiourea, triphenylphosphine and trioctylphosphine.

DETAILED DESCRIPTION OF THE INVENTION In the process of the present invention, a novel ternary catalyst is used which consists of a zirconium halide, the above-described organoaluminium compound and a Lewis base specified hereinbelow.

f I STMS/1777R tj 'Itr .2 The zirconium halide is a compound represented by formula below: ZrXaA4a (I) wherein X and A, which may be the same or different, each represents Cl, Br or I, and a is 0 or an integer of up to 4.

Specific examples of the zirconium halide represented by the formula include ZrCl 4 ZrBr 4 Zrl4, ZrBrCl 3 ZrBr 2 Cl, etc. Among these, ZrCl 4 is particularly preferred.

They can be used singly or two or more of them can be used in combination.

The organoaluminium compound which can be used in the present invention is an alkylaluminium sesquihalide represented by formula (II) below: AIR' Q 1

(II)

1.5 1.5 wherein R 1 represents an alkyl group having from 1 to 20 carbon atoms, and Q 1 represents Cl, Br or I (formula (II) may also be expressed as Al R 2 Q and or an alkylaluminium compound represented by formula (III) below: AR42b3-b

(III)

wherein R2 and Q2, which may be the same or different, have the same meanings as R1 and Q1 in formula (III), and b is an integer of 1 to 3.

The alkylaluminium sesquihalide represented by formula (II) above, is not limited particularly as far as R 2 and Q2 in formula (II) satisfy the above-described conditions.

Specific examples thereof include A1 2

(CH

3 3 C1 3 Al 2

(CH

3 3 Br3: A1 2

(C

2

H

5 )3Cl 3 A1 2

(C

2 H5) 3 Br 3 A1 2

(C

2

H

5 3

I

3 Al 2

(C

2 5 3 BrCl 2 A1 2 (C3H 7 3 Cl 3 Al 2 (iso-C 3

H

7 3 Cl3, A1 2

(C

4

H

9 3 C1 3 ji

I

5 Al 2 (iso-C4H 9 )3C1 3 A1 2

(C

5

H

11 3 C1 3 A1 2

(C

8

H

17 )3C1 3 A1 2

(C

2

H

5 2

(CH

3 )C1 3 etc.

Among these, compounds in which R 1 represents a methyl group, an ethyl group, a propyl group or a butyl group are preferred and those in which R 1 represents an ethyl group are particularly preferred.

It is preferred that Q1 represents Cl.

Specifically, ethylaluminium sesquichloride (A1(C 2

H

5 )1.

5 C1 1 5 A1 2

(C

2

H

5 3 C1 3 is preferred.

These alkylaluminium sesquihalides can be used singly or two or more of them can be used in combination.

The alkylaluminium compound represented by formula (III) above is not limited particularly as far as R 2 and Q 2 in formula (III) satisfy the above-described conditions. Specific examples thereof include A1 3

(CH

3 3 Al(C 2

H

5 3 Al(C 3

H

7 3 Al(iso-C 3

H

7 3 ,Al(C 4

H

9 3 Al(iso-C 4 H9) 3 Al(C 5 HjI) 3 Al(C 6

H

13 3 Al(C 8

H

17 )3 Al(C 2

H

5 2 C1, Al(0 2

H

5 2 Br, Al(C 2

H

5 2 1, Al(C2H 5 )Cl 2 Al(C 2

H

5 )Br 2 Al(C 2

H

5 )1 2 etc.

However, among the compounds represented by formula (III), those in which b is 2 or 3 are preferred.

o In formula (III), R 2 is preferably an ethyl group, ooo a propyl group, a butyl group or an isobutyl group and more preferably an ethyl group.

It is preferred that Q 2 represents Cl.

Specifically, compounds such as triethylaluminium, diettylaluminium chloride and ethylaluminium dichloride are preferred.

These alkylaluminium compounds can be used singly or two or more of them can be used in combination.

6 The Lewis base is at least one member selected from sulfur compound group consisting of thiophenes, methyl disulfide and thiourea, and a phosphorus compound group I consisting of triphenylphosphine and trioctylphosphine.

These compounds can be used singly or two or more of them can be used in combination.

In the process of the present invention, the objects of the present invention can be attained by the use of a catalyst comprising a combination of the above zirconium halide, the two organoaluminum compounds represented by the formulas (II) and (III) and the Lewis base and the use of specific solvent i referred to hereafter.

When these catalysts are used, not only the content of wax in the product of oligomerization reaction can be further j reduced but alsn the yield of linear (X-olefins per weight of izirconium halide can be increased and the purity of the linear I G(-olefin obtained can be increased.

Mixing ratio of the two organoaluminum compounds represented by the formulas (II) and (III) (AIR 1 Ql /A1R 2

Q

2 S1.5 1.5 b 3 b (molar ratio) is from 2 to 10, preferably from 3 to In the present invention, there is no particular limitation on the method of preparing catalysts from said zirconium halide, said two organoaluminum compounds and said Lewis base. However, it is preferred to contact the zirconium halide with the organoaluminum compounds in a suitable inert solvent to form a catalyst preparation liquor which contain a catalyst precursor and then mix this catalyst preparation liquor with the Lewis base upon or prior to the polymerization (oligomerization) of ethylen.e to obtain a catalyst liquor.

7 8 Upon preparation of the catalyst preparation liquor or catalyst liquor, it is desirable that the mixture is heated at a suitable temperature (usually, a temperature lower than the temperature of polymerization reaction. ^r example, and more specifically within the range of from 60 to 8(0C) for from 10 to 120 minutes to activate the catalyst.

Said inert solvents comprise at least 75% by weight of one or more naphthenic solvents.

Examples of suitable naphthenic solvents, include, cyclopentane, cyclohexane, methylcyclopentane, and methylcyclohexane. Among them, cyclohexane is preferred.

Other solvents which may be used include aromatic solvents, for example, benzene, toluene, xylene, chlorobenzene, ethylbenzene, dichlorobenzene and chlorotoluene. Among them, benzene is preferred.

When cyclohexane is used as the solvent and the catalyst is oo", composed properly, the catalyst having good activity is obtained. As a S result, a product made mostly of linear c,-olefins having desired molecular weights is produced. As shown in Table 1 which summarizes the oo;o results of the Examples described hereinafter, production of by-product sec-butyl benzene is reduced by adoption of at least 75% by weight of cyclohexane as the solvent. The best results were achieved with 100% cyclohexane.

When benzene is used as the solvent, alkylbenzene by-products are produced by the Friedel-Crafts reaction of the benzene solvent with linear a-olefin products having more carbon atoms than butene-1 in case of the catalyst being deactivated by ordinary methods.

When a mixture of benzene and cyclohexane is used as the solvent, a property of the solvent depends on the ratio of the amount of benzene to Sthat of cyclohexane. That is, under the condition that components and compositions of the catalyst are the same, when the amount of cyclohexane in the mixture is increased, the activity of the catalyst is gradually lowered, a-olefins having low molecular weights are mostly produced, and little alkylbenzene by-products are produced.

Aliphatic hydrocarbons such as heptane are not preferred because the products obtained contain impurities.

v .,MS/1777R 7 K

I

9- Therefore the preferred solvent mixture of the present iv~L~r comprises at least 75% by weight of a naphthene such as cyclohexane with an aromatic solvent such as benzene.

4~ 44 4 4 I 4 I 00 I I 04 410 t~ 4040 44 44 4 M S/17 77 R

T

These solvents may be used singly or in combination of two or more.

In the present invention, the proportion of the zirconium halide, the two organoaluminum compounds, Lewis base and the solvent is, based on 250 ml of the solvent, usually from 0.005 to 5 mmol and p;-eferably from 0.01 to 1 minol, of the zirconium halide, usually from 0.02 to 15 mmol and preferably from 0.05 to 3 mmol. of the organoaluminum compounds and usually from 0.01 to 20 mmol and preferably from 0.02 to 20 mmol, of the Lewis base when sulfur compounds (thiophenes, methyl disulfide, thiourea) are used or from 0.01 to 5 mmol of the Lewis base when phosphorus compounCs (triphenylphosphine, trioctylphosphine) are used. \s for the proportion of the zirconium halide and the organualuminum compounds q 1 5 A1K Q2-b ZrXaA 4 a) (molar ratio,sometimes I(i 5Q-.5 S referred to as "Al/Zr hereinafter), more desirable results can be obtained by setting the proportion of the A1/Zr within the range of from 3 to 15, preferably from 5 to Upon polyr ,rization, the catalyst liquor can be ixed with the solvent to adjust the concentration of the catalyst, if desired.

The thus prepared catalyst or catalyst liquor and ethylene or a gas containing ethylene are contacted in the above-described solvent at a predetermined reaction temperature under a predetermined reaction pressure to carry out polymerization (oligomerization) of ethylene efficiently.

The gas containing ethylene which can be used in the present invention include an inert gas containing ethylene, 10 purified ethylene gas for polymerization, ethylene gas for pclymerization such as high purity ethylene, etc., with high purity ethylene being preferred.

The reaction temperature upon polymerization is usually fiom 50 to 200°C, preferably from 100 to 150 0

C.

The reaction pressure is usually not lower than 5 Kg/cm2 (gauge pressure), preferably not lower than 25 Kg/cm 2 (gauge pressure). The reaction time is usually from about 5 minutes to about 2 hours, preferably from about 15 minutes to about 1 hour.

All the operations starting from the preparation of I the catalyst to the completion of the polymerizaton reaction are desirably carried out in the absence of air and moisture.

It is preferred that the preparation of the catalyst is carried out under the atmosphere of an inert gas such as nitrogen, argon, etc.

Further, it is desirable that starting materials for preparing the catalyst, solvent and starting materials for polymerization are dried sufficiently. However copresence of a minute amount of moisture or air sometimes results in increase in the activity and selectivity of the catalyst.

Hereinafter, example of the process for pr paring linear C--olefins according to the present invention will be described in detail.

That is, in a vessel equipped with a stirrer there are dissolved the zirconium halides, zirconium tetrachloride, and the organoalminum compounds, ethylalum.nium sesquichloride, in the solvent, benzene, under 11 the atmosphere of the inert gas, argon, nitrogen, etc., and heated at a temperature of from 60 to 80°C for from 10 to 120 minutes with stirring to prepare a catalyst preparation liquor.

i A portion of the catalyst preparation liquor thus obtained is transferred to another vessel equipped with a stirrer under the atmosphere of the inert gas and diluted with the solvent, benzene, and then the Lewis base, e.g., thiophene, is added thereto at a temperature in the vicinity of room temperature frllowed by stirring to prepare a catalyst liquor. As a result of the preparation of the catalyst in j this manner a complex catalyst derived from a zirconium halide such as zirconium tetrachloride and an alkylaluminium compound is formed, and use of the complex catalyst results In increase in the yield and purity of the objective product, linear (-olefins.

Then, the above-described catalyst liquor is pressed into a reaction vessel kept at a temperature of from 50 to under the atmosphere of an inert gas, and while stirring the catalyst liquor a gas containing ethylene such as high purity ethylene is introduced followed by oligomerizing ethylene is introduced followed by oligomerizing ethylene under the LJ above-described reaction conditions.

After a predetermined period of time a conventional catalyst deactivating agent such as an aqueous alkali solution or an aqueous methanol solution containing an alkali can be added to the reaction mixture to stop the reaction.

12 As for the catalyst deactivating agent, there be cited, for example, water, alcohols (monohydric alcohols, polyhydric alcohols, cyclic alcohols, acyclic alcohols, aliphatic alcohols, aromatic alcohols), ether carboxylic acids, phenols, etc.

It is desired to properly select the catalyst deactivating agent.

That is, when aromatic solvents are used as a so-vent at preparation of catalyst or a polymerization solvent, it is preferred to use an ether (for example tetrahydrofuran and ethy ether) as the catalyst deactivating, agent and when naphthenic solvents are used as a solvent at preparation of catalyst or a polymerization solvent, it is preferred to use an aqueous alkali solution, especially aqueous sodium hydroxide solution.

j When the catalyst is deactivated it is preferred to add a nitrogen containing compound in addition to the catalyst deactivating agent described above to the reaction mixture since addition of halogen derived from the catalyst to the resulting linear (X-olefin can be prevented by the addition i of the nitrogen containing compound, thus further improving the purity of the linear (-olefin.

As for the nitrogen containing compounds, there can be cited, for example, ammonia or amines such as methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, cyclohexylamine, octylamine, decylamine, aniline, benzylamine, naphthylamine, dimethylamine, diethylamine, dibutylamine, diphenylamine, methylphenylamine, trimethylamine, triethylamine, tributylamine, triphenylamine, pyridine, picoline, etc.

13 :1 i

I

These nitrogen containing compounds can be used singly or two or more of them can be used in combination.

The order of adding the deactivating agent and the nitrogen containing compound to the reaction mixture is not limited particularly. For example, the order of addition may be first to add the nitrogen containing compound and then the deactivating agent, to simultaneously add the nitrogen containing compound and the deactivating agent.

After deactivation of the catalyst in the abovedescribed manner the resulting product liquor contains high content of linear 0(-olefins which have from about 6 to about 44 carbon atoms, particularly from 6 to 20 carbon atoms in good yield and which do not contain halogen. On the other hand, by-production of wax component is remarkably reduced.

The reaction product liquor after deactivation of the catalyst can be subjected to post-treatments, washing with water, etc., separation such as extraction, filtration, etc., drying and the like to recover the objective products, linear O(-olefins of high purity in high efficiency.

That is, according to the process of the present invention, linear O-olefins of such high purity that they contain from about 6 to about 20 carbon atoms can be obtained stably in high yield and at high selectivity. It is possible to control the carbon atom number distribution of the product to a further narrow range by appropriately selecting the reaction conditions, catalyst composition, concentration, etc.

The unused ethylene or a low boiling point fraction containing unused ethylene which is recovered may be used as it is or recycled after purification for use as a starting material for the reaction.

14 ;1 The linear 0(-olefins prepared according to the process of the present invention can be used advantageously as a comonomer for preparing various copolymers and also empolyed in various fields of industry such as plasticizers, starting materials for preparing surface active agents.

According to the present invention, the following effects can be obtained.

That is, in the process of the present invention, use of the catalyst prepared from a zirconium halide, two organoaluminium compounds and a specified Lewis base and use of an inert solvent enable preparation of linear (X-olefins of high purity and reduction in the amount of by-produced wax.

Particularly, the catalysts prepared from a mixture S of zirconium tetrachloride, alkylaluminium sesquihalide and I trialkylaluminium and specific limited Lewis base have a high activity, and when these catalysts are used linear Q(-olefins of higher purity can be prepared, the amount of wax by-produced can be reduced further, and the yield of linear Q-olefins based on the zirconium tetrachloride can be increased.

S,4 Further, in the process of the present invention, addition of a nitrogen containing compound upon deactivation of the catalyst in the resulting polymerization reaction product Lliquor obtained by oligomerization of ethylene the content of halogen in the linear (-olefins can be reduced and linear fY-olefins of higher purity can be prepared.

In addition, when the reaction is carried out at high temperatures by-production of wax component is in a small amount and therefore operational performance of the process is improved greatly, thus enabling long production runs.

15

EXAMPLES

The present invention will be described in greater detail with reference to the following examples and comparative examples.

EXAMPLES 1, 2, and 3 Preparation Example of Catalyst (Preparation of Catalyst Liquo In a 1,000 ml flask equipped with a stirrer were introduced 50 mmol of anhydrous zirconium tetrachloride d 472 ml of dry benzene under the atmosphere of argon a the resulting mixture was stirred for 30 minutes. To e mixture was added the alkylaluminium compound shown in ble 1 in S such an amount that it occupies a molar ratio/to zirconium tetrachloride calculated from the amount dicated in Table 1, and the mixture was stirred at 60°C for 30 minutes to obtain So, a catalyst preparation liquor.

Then, in a 500 ml three neck flask were introduced dry benzene and the catalyst p eparation liquor in predetermined amounts, respectively, unde the atmosphere of argon, followed by adjusting the amounts of zirconium tetrachloride, the ethylaluminium compound indicated and benzene to the values indicated in Table 1. To tl resulting mixture was added a predetermined amount of thiop ene as a third component and the mixture was stirred at r om temperature for 10 minutes to obtain a catalyst liquor.

Prepar tion Example of -0Olefin (Oligomerization of Ethylene) In a 1 liter autoclave equipped with a stirrer was ntroduced the catalyst liquor prepared in the above described /rarainxamleef atav b nvvn -in gi i 16 Preparation Example of Catalyst In a 1,000 ml flask equipped with a stirrer were introduced 50 mmol of anhydrous zirconium tetrachloride and 472 ml of dry benzene under the atmosphere of argon and the resulting mixture was stirred for 30 minutes.

Then, to the mixture was added the alkylaluminum compound shown in Table 4 in such an amount that it occupies a molar ratio to zirconium tetrachloride as shown in Table 4 and the mixture was stirred at 70 0 C for 30 minutes to obtain a catalyst liquor.

Thereafter, in a 500 ml three-neck flask were introduced dry benzene and the catalyst liquor in predetermined amounts.

Moreover, to this mixture was added thiophene, followed by stirring at room temperature for 10 minutes.

The molar ratio ((C 2

H

5 3 Al 2 C1 3 2

H

5 3 Al}/Zrcl 4 was and (C 2

H

5 3 Al 2 C1 3

/(C

2 5 Al was Preparation Example The catalyst liquor prepared above was introduced in an autoclave equipped with a stirrer by conveying using pressurized dry argon.

Temperature of the autoclave was kept at 50 to 60 0

C.

After the charging of the catalyst liquor was over, stirring was started and high purity ethylene gas was introduced rapidly into the autoclave and the charging was continued until the inside pressure reached the reaction pressure indicated in Table 4. Then '?mperature was raised to the reaction temperature Ci

BW-

shown in Table 4. Introduction of ethylene was continued in an amount necessary to maintain the reaction pressure. After lapse of 30 minutes under the reaction conditions, an aqueous sodium hydroxide solution was pressed into the autoclave to deactivate the catalyst and thus stop the reaction.

The following post-treatments were carried out.

At first, 20 g of undecane for use as an internal standard for chromatography was added to the reaction product and wax component was filtered out using a filter paper. The wax component on the filter paper washed sufficiently with benzene to drip down light fraction in the filtrate. The filtrate was washed twice with 500 ml of deionized water and dried over anhydrous potassium carbonate.

The thus obtained colorless and transparent solution of the reaction product was analyzed by gas chromatography.

The yield of the product was obtained by internal standard method.

The wax component filtered out was weighed after it o404 x" was air-dried and then dried in a vacuum drier at a pressure of mmlg.

The yield of C4 to C8 fractions was calculated from the Schltz-Flory distribution since operational loss could not be avoided.

The yield of C20+ in Table 4 was sum of the yield of obtained from gas chromatography and the above yield of the wax component.

-4- LZ HJZK'5)331L3q '12.' 2 ri) 3 br 3 A12 U 2 1 5 3

I

3 A1 2

(C

2

H

5 3 Br1 2 A1 2

(C

3

H

7 3 C1 3 A1 2 (is-C 3

H

7 3 C1 3 A1 2 (C4H 9 3 G1 3 5 Z- I V 2 19 EXAMPLE 1 Comparative Example 1 was repeated except that cyclohexane was used in place of benzene as solvent.

The results are shown in Table 1.

EXAMPLE 2 Comparative Example 1 was repeated except that the molar ratio

{(C

2

H

5 3 A1 2 C1 3

(C

2

H

5 3 A1}/ZrC14 was 7 and the molar ratio (C2H 5 3

A

2 C1 3

/(C

2

H

5 3 Al was The results are shown in Table 1.

COMPARATIVE EXAMPLE 2 AND EXAMPLES Comparative Example 1 was repeated except that benzene-cyclohexane mixed solvent having the mixing ratio as shown in Table 1 was used in place of benzene as the solvent.

The results are shown in Table 1.

COMPARATIVE EXAMPLE 3 Example 3 was repeated except that n-heptane was used in place of benzene as the solvent.

The results are shown in Table 1.

COMPARATIVE EXAMPLE 4 aI r ao aC B Soc.

slt Comparative Example 3 was repeated except that the molar ratio

{(C

2

H

5 3 A1 2 C1 3

(C

2

H

5 3 A1}/ZrC1 4 was 7 and the molar ratio (C 2

H

5 3 A1 2 C1 3

/(C

2

H

5 3 A1 was EXAMPLES 6-10 Comparative Example 2 was repeated except that Lewis bases as shown 25 in Table 2 were used in place of thiophene and cyclohexane was used as the solvent.

The results are shown in Table 2.

I COMPARATIVE EXAMPLE Comparative Example 2 was repeated except that thiophne was omitted. The results are shown in Table 2.

s TMS/1777R ,i VTI O

,PUR

00 OC TableI co. EKI EX. I Ex. 2 1C. Ex. 2 Ex. 3 Ex. 4- Ex. 5 Co. Ex. S Co. EX.

Z0. (MI -05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.10 EASC (mmo) 0.21 0.21 0.272 0.21 0.21 0-21 0.21 0.21 0.58 Catalyst TEA (mmol)1 2 1 0.04 0.04 0.078 0.04 0.04 0.04 0.04 0.04 0.12 component Thiophene (mmo 1) 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.60 A 9 /Z r (m lar ratio)"' Z Z) 7 5 5 5 7 EASC,'TEA (molar ratio) 3.531- Recin Reaction temperature 0 C) 120 120 120 120 1201 120 120 120 120 conditions Reaction pressure (kg/cm 2 G )6 65 55 5 55 3 1 65 65 55 Reaction time (min) 30 30 "D 30 30 31 31 30 Kind of solvent Benzene Cyclohexane Cyclohexane Benzene Benzene Benzene Benzene n-Heptane n-Heptane Solvent ratio (weight ratio) 50/50 25/75 15/85 57/95 Amount of solvent (mE9 250 250 250 250 250 250 250 250 250 Activity (g:Ig ZrC 9- 4 9320 C 4 (wty) 15.2 18.5 15.1 14.7 15.0 17.3 18.0 14.8 18.3 0 6 (Wrt%) 15.3 18.0 15.5 15.2 16.2 17.1 17.6 15.2 17.8 0 8 (70/6) 14.3 15.5 14.2 14.0 14.5 15.0 15.3 14.0 15.4 C 1 0 12.0 12.5 12.1 12.0 12.3 12.4 12. 12.1 12.5 C 1 2 9-2 9.7 10.0 10.0 9.9 9.8 9.7 10.0 9.8 0 14 6 7.3 8.0 8.0 7.8 7.5 7.4 8.0 7.4 C 1 6 5. 5.4 6.2 5.3 6.0 5.7 5.5S 5.3 Cl 8 4.9 3.9 4.8 4.9 4.6 4.2 4.0 4.9 020+ 13-7 9.1 14.1 14.9 12-5 10.9 10.0 14.7 9.3 0 18 purity 95-2 96.3 95.4 958 95.5 95.2 94.6 'V5.3 82.1 Catalyst se c-BuBz (wtppml I -decene) 480 14;4 L 1. (C2 H 5 s 2 AD.

2 0913 Ethylaluminum sesquichloride (02 Ha AD., C91.

Hs AD. Triethylaluminum r4) Deactivation with ie 4utous sodium hydroxide solution S)s e c B u B z ;sec-Butylbenzeae Hs 5 A9 rC 9 ~1V72~22~ Table 7 Ex- (o Ex. 7 Ex. S Ex. Ex-10 Co- Ex. S Zrce 4 9 mo1) 0.05 0.05 0.05 0.05 0.05 0.05 EASC 0-272 0.272 0.272 0.272 0.272 0.272 TEA (mw1) 2 0.078 0-078 0-078 0.078 0-078 0.078 methyl disulfide 0.02 Catalyst aniline 0.075 component thiourea 0.15 triphenyiphosphine 0.10 trioctylphsphine 1 0.05 A -1Z(molar ratio)"' 7 7 7 7 7 EASC/TEA (molar ratio) 3.53 3.5 3.5 1 Reaction conditions Reaction. temperature 120 120 120 120 120 120 Reaction pressure (kg/c- 2 G 65 55 55 55 55 Reaction time (min) 30 30 30 30 30 Kind of solvent Cyclohexane Cyclohexane Cyclobexarve Cyclohexane Cyclohexane Cyclohexane Amunt of solvent 250 250 250 250 250 250 Activity (gig ZrC.) 7530 7840 7340 6650 7640 8520 C4 14.3 14.7 15.5 13.0 12.3 12.5 Cs 14.9 15.2 15.8 13.9 13.2 13.5 Cs 13.8 14.0 14.4 13.1 12.? 12.9 C 1 0 12.0 12.1 12.2 11.7 11.4 11.5 C12 10.3 10.0 10.0 9.9 9.9 9.9 C 14 8.1 8.0 7.9 8.2 8.3 8.3 C16 6-4 6.3 56.1 .7 6.8 5.8 C 18 5.0 4.9 4.7 5.3 5.5 5.4 15.5 14.8 j 13.4 18.2 19.9 18.9 C18 purity 95.2 1 95.4 1 95. 1 95.9 (C2 H 5 A9 2 C93 z )z with aqueous sodium hydroxide solution

(C

2 Hs A-2 2 C9:, Ethylaluminum sesquichloride (C2 Hs )z A9 Triethylaluminum Deactivation A9 /Z rC9

Claims (9)

1. A process for preparing a linear a-olefin having from 6 to 18 carbon atoms comprising polymerizing ethylene or an ethylene containing a-olefin in the presence of a catalyst consisting of a zirconium halide, an organo-aluminum compound and a Lewis base in an inert solvent which comprises at least 75% by weight of a naphthenic hydrocarbon solvent and stopping the polymerization by adding a catalyst deactivating agent to the resulting reaction mixture, wherein said catalyst contains a zirconium component comprising a zirconium halide represented by formula ZrXaA 4 (I) wherein X and A may be the same or different and each represents chlorine, bromine or iodine atom and a is 0 or an integer of 1-4; an aluminum component comprising an alkylaluminum compound represented by .o formula (II): ')AIR AlR 1 1.5 SA'1 5 Q wherein R represents an alkyl group of 1-20 carbon atoms, Q represents chlorine, bromine or iodine atom, R and Q may be the same or different, respectively, and said formula (II) may also be represented by A1 2 R 3 Q 3 and an alkylaluminum compound represented by formula (III): AIR 2b AIRbQ b (II) il'i wherein R and Q2 have the same meanings as R 1 and Q 1 above R 2 and Q may be the same or different, respectively, and b is an integer of 1-3; said catalyst being mixed at a molar ratio I{A1R. 5 Q 1 5 AIRbQ _b}/ZrXaA4_ a of said zirconium component and aluminum component of 3-15 and at a molar ratio (A1R 1 5 Q 1 5/A1R Qb) of the components represented by formulae (II) and (III) of 2-10; said catalyst further contains at least one Lewis base selected from the group consisting of thiophene, methyl disulfide, thiourea, triphn ylphosphine and trioctylphosphine. IMS/1777R M$8 J,' 23

2. A process according to claim 1 wherein said inert solvent is Ssubstantially naphthenic.

3. A process according to claim 1 or 2 wherein said inert solvent further comprises one or more aromatic hydrocarbon solvents.

4. A process according to claim 1 wherein said ';ert solvent i comprises 75% to 100% w/w of naphthenic solvents and 0 to 25% w/w of at least one aromatic hydrocarbon solvent. A process according to claim 3 or 4 wherein the naphthenic solvent is cyclopentane or cyclohexane and the aromatic solvent is benzene, toluene or xylene. i 6. A process according to any one of claims 1 to 5 wherein i 0.005-5 mmols of the zirconium component, 0.02-15 mmols of the alkyl- aluminum compound and 0.02-20 mmols of the Lewis base when the Lewis base is selected from group consisting of thiophene, methyl disulfide and thiourea and 0.01-5 mmols of the Lewis base when the Lewis base is selected from the group consisting c~ triphenylphosphine and rioctylphosphine are used per 250 ml of the inert solvent. 1

7. A process according to any one of claims 1 to 6 where the zirconium halide is zirconium '-trachloride and R and R 2 are ethyl and Q 1 and Q2 are chlorine.

8. A process according to any one of claims 1 to 6 wherein the zirconium halide represented by the formula is zirconium tetrachloride, the alkylaluminum represented by the formula (II) is triethylaluminum sesquichloride and the alkylaluminum represented by the formula (III) is triethylaluminum.

9. A process according to any one of claims 1 to 8 further comprising the addition of at least one nitrogen compound selected from the group consisting of trimethylamine, triethylamine, ammonia gas, ammonia water and n-methyl- piperidine prior to the addition of the catalyst deactivating agent. A process for preparing linear a-olefins substantially as hereinbefore described with reference to any one of the Examples but excluding the comparative Examples.

11. The product of the process of any one of claims 1 to S/1777R

24- DATED this EIGHTEENTH day of MARCH 1992 Idemitsu Petrochemical Company Limited Patent Attorneys for the Applicant SPRUSON FERGUSON 0 Awl 777R