WO2020059869A1

WO2020059869A1 - Method for producing lubricant base oil

Info

Publication number: WO2020059869A1
Application number: PCT/JP2019/037084
Authority: WO
Inventors: 冬樹相田; 一生田川
Original assignee: Ｊｘｔｇエネルギー株式会社
Priority date: 2018-09-20
Filing date: 2019-09-20
Publication date: 2020-03-26
Also published as: JPWO2020059869A1; JP7232258B2

Abstract

Provided is a method for producing a lubricant base oil, the method comprising: a decomposition-purification step of thermolyzing a feedstock oil and purifying the obtained thermolyzed product to obtain ethylene; a polymerization step of oligomerizing the ethylene in the presence of an ethylene polymerization catalyst to obtain a polymer mixture containing an ethylene oligomer; a first distillation step of distilling the polymer mixture to fractionate the mixture into a lubricant fraction and a fraction other than the lubricant fraction; an isomerization step of hydroisomerizing the lubricant fraction in the presence of a hydroisomerization catalyst to obtain a reaction mixture containing an isomerized oil; and a second distillation step of distilling the reaction mixture to fractionate the mixture into a lubricant base oil and a fraction other than the lubricant base oil. The fraction, other than the lubricant fraction, obtained during the first distillation step and/or the fraction, other than the lubricant base oil, obtained during the second distillation step is/are returned to the decomposition-purification step as part of the feedstock oil.

Description

Manufacturing method of lubricating base oil

The present invention relates to a method for producing a lubricating base oil.

エチレン In the production of ethylene oligomer used as a raw material of lubricating base oil, a method for obtaining a high-purity ethylene oligomer containing no impurities is being developed. For example, Patent Literature 1 discloses a method in which a polymerization reaction of ethylene is performed in an organic solvent in the presence of a Ziegler-based catalyst, and the organic solvent separated by distilling the obtained polymerization reaction product is recycled to the polymerization reaction. A method for producing an ethylene oligomer to be used is described. In the production method, the concentration of an olefin having 3 or more carbon atoms in an organic solvent circulating in a polymerization reaction system is set to 2% by weight or less. .

JP-A-2002-255864

By the way, in the production of a lubricating base oil, in order to obtain a lubricating base oil corresponding to a target product from an ethylene oligomer which is a polymerization reaction product, it is necessary to go through various steps such as a distillation step and an isomerization step. is there. Therefore, in order to improve the yield of the target lubricating base oil, it is desirable that the reaction efficiency of the catalyst used in each step, including the ethylene polymerization reaction catalyst, be maintained as much as possible.

In this regard, the organic solvent separated from the polymerization reaction product obtained by the ethylene polymerization reaction contains unreacted ethylene, and the organic solvent containing unreacted ethylene is used again as a reaction solvent in the polymerization reaction system. By recycling the method described in Patent Document 1, it is possible to obtain an ethylene oligomer having a certain degree of high purity. However, the organic solvent also contains by-products (impurities) such as olefins, and when these impurities are supplied to the polymerization reaction system, the catalyst efficiency of the ethylene polymerization catalyst is reduced, and the intended lubricating oil This may cause a decrease in the base oil yield.

An object of the present invention is to provide a new method for producing a lubricating base oil, which can efficiently produce a lubricating base oil.

In order to solve the above problems, the present inventors have focused on fractions other than the lubricating base oil obtained by the distillation process, which have been of no use except for burning as a fuel in the production of lubricating base oils. did. Then, in the step of producing a lubricating base oil from ethylene oligomers, high-purity ethylene can be regenerated by reusing the fraction corresponding to the above as a part of the raw material oil in the thermal cracking step, and converting it to the polymerization step. It has been found that by using such a compound, it is possible to suppress the contamination of impurities such as olefins, which cause a decrease in the efficiency of the polymerization catalyst, and to produce a lubricating base oil in a high yield, thereby completing the present invention.

The method for producing a lubricating base oil according to the present invention comprises a step of pyrolyzing a feedstock oil, a step of purifying an obtained pyrolyzate to obtain ethylene, and a step of oligomerizing ethylene in the presence of an ethylene polymerization catalyst. A polymerization step of obtaining a polymerization mixture containing ethylene oligomer by distillation, a first distillation step of distilling the polymerization mixture into a lubricating oil fraction and a fraction other than the lubricating oil fraction, and hydrogenating the lubricating oil fraction. An isomerization step of hydroisomerizing in the presence of an isomerization catalyst to obtain a reaction mixture containing isomerized oil, and a second step of distilling the reaction mixture into a lubricating base oil and a fraction other than the lubricating base oil by distillation. And a second distillation step, wherein the fraction other than the lubricating oil fraction obtained in the first distillation step and / or the fraction other than the lubricating oil base oil obtained in the second distillation step It is characterized by returning to the decomposition purification process as a part of That.

In particular, it is preferable to return the fraction other than the lubricating base oil obtained in the second distillation step to the cracking and refining step as a part of the feed oil.

留 The fraction other than the lubricating base oil may be a lighter fraction lighter than the lubricating base oil.

According to the present invention, there is provided a new method for producing a lubricating base oil capable of efficiently producing a lubricating base oil.

2 is a result (chromatogram) of electrolytic desorption mass spectrometry (FD-MS) of the isomerized oil obtained in Example 1. It is a flow figure showing an example of a lubricating base oil manufacturing device for carrying out a lubricating base oil manufacturing method concerning one embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings as appropriate. However, the present invention is not limited to the following embodiments.

The method for producing a lubricating base oil according to the present embodiment comprises a cracking and refining step of thermally cracking a feedstock oil and refining an obtained pyrolyzate to obtain ethylene, and converting ethylene into an oligomer in the presence of an ethylene polymerization catalyst. A polymerization step of obtaining a polymerization mixture containing ethylene oligomers by distillation, a first distillation step of distilling the polymerization mixture into a lubricating oil fraction and a fraction other than the lubricating oil fraction, and hydrogenating the lubricating oil fraction with hydrogen. An isomerization step of hydroisomerizing in the presence of a hydroisomerization catalyst to obtain a reaction mixture containing an isomerized oil, and distilling the reaction mixture into a lubricating oil base oil and a fraction other than the lubricating oil base oil by distillation, respectively And a distillation step. Further, in such a production method, a fraction other than the lubricating oil fraction obtained in the first distillation step and / or a fraction other than the lubricating oil base oil obtained in the second distillation step are mixed with the base oil. It is supplied as part of the decomposition and purification steps.

According to the production method according to the present embodiment, it is possible to efficiently produce a target lubricating base oil. The reason why such an effect is obtained is that, of course, unreacted ethylene can be used again as a raw material for the polymerization step by returning it to the decomposition and purification step. It is conceivable that a decrease in catalyst efficiency can be suppressed. The present inventors consider the reason as follows.

First, the decrease in the catalytic efficiency of the ethylene polymerization catalyst is due to the fact that when unreacted ethylene is supplied again to the polymerization reaction system, by-products (impurities) such as olefins other than ethylene are also supplied to the polymerization reaction system. it is conceivable that. In contrast, in the method for producing a lubricating base oil according to the present embodiment, a fraction other than the lubricating oil fraction obtained in the first distillation step and / or the lubricating base oil obtained in the second distillation step The fraction other than oil is returned to the cracking and refining step as a part of the feedstock oil, and the high-purity ethylene obtained in the cracking and refining step is brought into contact with the ethylene polymerization catalyst in the polymerization step, whereby the catalytic activity of the ethylene polymerization catalyst is increased. It is considered that the contamination of impurities that hinder the reaction was suppressed, and as a result, the decrease in the catalytic efficiency of the ethylene polymerization catalyst could be suppressed.

In the method for producing a lubricating base oil according to the present embodiment, a fraction other than the lubricating oil fraction obtained in the first distillation step and / or a fraction other than the lubricating base oil obtained in the second distillation step Can be recycled as a part of the feedstock oil and returned to the cracking and refining process to regenerate ethylene, as well as basic chemicals such as propylene, butadiene, isoprene, cyclopentadiene, benzene, toluene, and xylene. It is also possible to co-produce goods.

Further, in the method for producing a lubricating base oil according to the present embodiment, since the high-purity ethylene regenerated by returning the fraction to a cracking and refining step as a part of the raw material oil is used as a raw material, a conventional slack wax or Improve the yield of lubricating base oil in all processes compared to the method for producing lubricating base oil in which feedstock such as atmospheric residual oil hydrocracked oil is subjected to hydrocracking / hydroisomerization process In addition to the above, it is also possible to suppress the traction coefficient of the obtained lubricating base oil. The present inventors presume that the reason for obtaining such an effect lies in the specificity of the carbon number distribution of the lubricating base oil obtained by the method for producing a lubricating base oil according to the present embodiment.

That is, first, in the case of a conventional wax isomerized oil, a raw material wax such as a wax obtained by FT synthesis is usually a hydrocarbon compound having an even number of carbon atoms (a hydrocarbon compound having 2n carbon atoms; n is 1 or more). And the same applies hereinafter) and a hydrocarbon compound having an odd number of carbon atoms (a hydrocarbon compound having 2n + 1 carbon atoms), and the ratio between the two is almost the same. In contrast, the ethylene oligomer obtained by the production method according to the present embodiment may undergo thermal decomposition accompanying isomerization (for example, formation of 2n-1 carbon paraffins due to isomerization of 2n carbon paraffins). However, most are hydrocarbon compounds having an even number of carbon atoms (hydrocarbon compounds having a carbon number of 2n), and exhibit a unique carbon number distribution in which the proportion of hydrocarbon compounds having an even number of carbon atoms is large. .

The ethylene oligomer obtained by the method for producing a lubricating base oil according to the present embodiment exhibits such a specific carbon number distribution, so that the traction coefficient of the obtained lubricating base oil can be suppressed. The inventors are thinking.

Hereinafter, each step will be described in detail.
(Decomposition / purification process)
In the cracking and refining step, the raw oil is thermally cracked, and the obtained thermally cracked product is purified to obtain ethylene. Specifically, a method of introducing a feedstock oil into a pyrolysis refining device such as a naphtha cracker can be used. The raw material oil to be subjected to thermal cracking includes at least a fraction other than the lubricating oil fraction obtained in the first distillation step and / or a fraction other than the lubricating oil base oil obtained in the second distillation step. Including. These fractions will be described in detail in a first distillation step and a second distillation step described below.

In the cracking and refining process, after the raw oil is thermally cracked, the resulting pyrolyzate (cracked oil) may be subjected to a refining process to obtain higher-purity ethylene. When a naphtha cracker or the like is used, the naphtha cracker purification step can be used as it is. By including the purification step, it is possible not only to obtain ethylene with higher purity, but also to obtain basic chemicals such as propylene, butadiene, isoprene, cyclopentadiene, benzene, toluene, and xylene with high purity. The purity of ethylene obtained through the purification step is, for example, preferably 99.0% or more, more preferably 99.5% or more, and still more preferably 99.9% or more.

The content of the fraction other than the lubricating oil fraction obtained in the first distillation step and / or the fraction other than the lubricating base oil obtained in the second distillation step contained in the feedstock is not particularly limited. For example, it is preferably 0.01% by mass or more, more preferably 1% by mass or more, and further preferably 10% by mass or more. The upper limit of the content of the fraction contained in the feedstock is also not particularly limited, and is, for example, usually less than 100% by mass, preferably 90% by mass or less, more preferably 80% by mass or less. In addition, from the viewpoint of stable operation of the thermal cracking and refining apparatus, it is preferable to use a raw material oil in which the content of the fraction is kept constant.

原料 As the material contained in the base oil other than the above-mentioned fraction, a base oil (naphtha) usually subjected to thermal cracking can be used without any particular limitation. In addition to naphtha, it is also possible to use ethane, LPG, kerosene, light oil, and the like.

方法 The method of obtaining the cracked oil containing ethylene by pyrolyzing the base oil can be appropriately set according to the composition of the base oil to be subjected to the pyrolysis and the intended performance of the lubricating base oil. For example, the thermal decomposition temperature is preferably from 700 to 1000 ° C., and the residence time is preferably from 0.001 to 10 seconds. After pyrolysis, the product is rapidly cooled and distilled, and in addition to ethylene, C3 components including methane and propylene, C4 components including butadiene, C5 components including isoprene and cyclopentadiene, components such as benzene, toluene, and xylene. It is possible to separate

(Polymerization step)
In the polymerization step, the ethylene obtained in the decomposition and purification step is oligomerized in the presence of an ethylene polymerization catalyst to obtain a polymerization mixture containing an ethylene oligomer. As a specific embodiment, for example, there is a method of introducing ethylene into a polymerization reactor filled with an ethylene polymerization catalyst. The method of introducing ethylene into the polymerization reactor is not particularly limited. In addition, as long as the effects of the present invention are not significantly impaired, α-olefins such as propylene and 1-butene may be copolymerized.

溶媒 At the time of the polymerization reaction, a solvent is usually used. Examples of the solvent include aliphatic hydrocarbon solvents such as butane, pentane, hexane, heptane, octane, cyclohexane, methylcyclohexane, and decalin; and aromatic hydrocarbon solvents such as tetralin, benzene, toluene, and xylene. Solution polymerization, slurry polymerization, and the like can be performed by dissolving an ethylene polymerization catalyst in these solvents. Since the ethylene oligomer has an even number of carbons, it is preferable to use a solvent having an odd number of carbons to facilitate separation from the ethylene oligomers. Pentane, heptane, methylcyclohexane, toluene and the like are suitable for the property.

The reaction temperature in the polymerization reaction is not particularly limited, but from the viewpoint of catalyst efficiency, for example, preferably -50 ° C to 100 ° C, more preferably -30 ° C to 80 ° C, further preferably -20 ° C to 70 ° C, particularly Preferably between -10 ° C and 60 ° C, very preferably between -5 ° C and 50 ° C, most preferably between 0 and 40 ° C. When the reaction temperature is −50 ° C. or higher, precipitation of the produced polymer can be suppressed while maintaining the catalyst activity, and when the reaction temperature is 100 ° C. or lower, decomposition of the catalyst can be suppressed. Also, the reaction pressure is not particularly limited, but is preferably, for example, 100 kPa to 5 MPa. Although the reaction time is not particularly limited, it is, for example, preferably 1 minute to 24 hours, more preferably 5 minutes to 60 minutes, further preferably 10 minutes to 45 minutes, and particularly preferably 20 minutes to 40 minutes. It is of course possible to polymerize for more than 24 hours as long as the catalyst has activity.

The ethylene polymerization catalyst is not particularly limited, and examples thereof include a catalyst containing an iron complex represented by the following general formula (1).

中 In the formula (1), R represents a hydrocarbyl group having 1 to 6 carbon atoms or an aromatic group having 6 to 12 carbon atoms, and a plurality of Rs in the same molecule may be the same or different. R 'represents a free radical having an oxygen atom and / or a nitrogen atom, and a plurality of R's in the same molecule may be the same or different. Y represents a chlorine atom or a bromine atom.

ヒドロ Examples of the hydrocarbyl group having 1 to 6 carbon atoms include an alkyl group having 1 to 6 carbon atoms and an alkenyl group having 2 to 6 carbon atoms. The hydrocarbyl group may be linear, branched or cyclic. Further, the hydrocarbyl group may be a monovalent group in which a linear or branched hydrocarbyl group and a cyclic hydrocarbyl group are bonded.

Examples of the alkyl group having 1 to 6 carbon atoms include straight-chain alkyl groups having 1 to 6 carbon atoms such as methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group and n-hexyl group; -Propyl group, iso-butyl group, sec-butyl group, tert-butyl group, branched pentyl group (including all structural isomers), branched hexyl group (including all structural isomers), etc. A branched alkyl group having 3 to 6 carbon atoms; a cyclic alkyl group having 1 to 6 carbon atoms such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group.

Examples of the alkenyl group having 2 to 6 carbon atoms include linear alkenyl groups having 2 to 6 carbon atoms such as ethenyl group (vinyl group), n-propenyl group, n-butenyl group, n-pentenyl group and n-hexenyl group; carbon such as iso-propenyl group, iso-butenyl group, sec-butenyl group, tert-butenyl group, branched pentenyl group (including all structural isomers), and branched hexenyl group (including all structural isomers) A branched alkenyl group having 2 to 6 carbon atoms; a cyclic alkenyl group having 2 to 6 carbon atoms such as a cyclopropenyl group, a cyclobutenyl group, a cyclopentenyl group, a cyclopentadienyl group, a cyclohexenyl group, and a cyclohexadienyl group. .

芳香 Examples of the aromatic group having 6 to 12 carbon atoms include a phenyl group, a toluyl group, a xylyl group, and a naphthyl group.

において In the formula (1), a plurality of R and R ′ in the same molecule may be the same or different, but may be the same from the viewpoint of simplifying the synthesis of the compound.

The free radical having an oxygen atom and / or a nitrogen atom may be a free radical having an oxygen atom and / or a nitrogen atom and having 0 to 6 carbon atoms, for example, a methoxy group, an ethoxy group, an isopropoxy group, a nitro group. And the like.

として Specific examples of such an iron complex include compounds represented by the following formulas (1a) to (1h). These iron complexes can be used alone or in combination of two or more.

In the iron complex represented by the general formula (1), a compound constituting a ligand (hereinafter, also referred to as a diimine compound) is, for example, dehydrated and condensed with dibenzoylpyridine and an aniline compound in the presence of an acid. Can be synthesized.

A preferred embodiment of the method for producing a diimine compound includes a first step of dissolving 2,6-dibenzoylpyridine, an aniline compound, and an acid in a solvent, and dehydrating and condensing the solvent under reflux with heating, and a reaction mixture after the first step. A separation and purification process for obtaining a diimine compound.

酸 As the acid used in the first step, for example, an organoaluminum compound can be used. Examples of the organoaluminum compound include trimethylaluminum, triethylaluminum, tripropylaluminum, triisopropylaluminum, tributylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, diethylaluminum chloride, ethylaluminum dichloride, ethylaluminum sesquichloride, and methylaluminoxane And the like.

プロトン As the acid used in the first step, a protonic acid can be used in addition to the above-mentioned organoaluminum compound. Protic acids are used as acid catalysts that donate protons. The protonic acid used is not particularly limited, but is preferably an organic acid. Examples of such a protonic acid include acetic acid, trifluoroacetic acid, methanesulfonic acid, trifluoromethanesulfonic acid, and paratoluenesulfonic acid. When using these protonic acids, it is preferable to remove by-produced water with a Dean-Stark water separator or the like. Further, the reaction can be performed in the presence of an adsorbent such as molecular sieves. The amount of the protonic acid added is not particularly limited, and may be a catalytic amount.

溶媒 Further, examples of the solvent used in the first step include a hydrocarbon solvent, an alcohol solvent, and the like. Examples of the hydrocarbon solvent include hexane, heptane, octane, benzene, toluene, xylene, cyclohexane, methylcyclohexane and the like. Examples of the alcohol-based solvent include methanol, ethanol, isopropyl alcohol and the like.

反応 The reaction conditions in the first step can be appropriately selected depending on the types and amounts of the starting compound, the acid and the solvent.

分離 In addition, the separation / purification treatment in the second step is not particularly limited, and examples thereof include silica gel column chromatography and a recrystallization method. In particular, when the above-mentioned organoaluminum compound is used as the acid, it is preferable to mix the reaction solution with a basic aqueous solution, decompose and remove aluminum, and then purify.

The iron complex contains iron as a central metal. The method of mixing the diimine compound and iron is not particularly limited, for example,
(I) a method of adding and mixing an iron salt (hereinafter sometimes simply referred to as "salt") to a solution in which the diimine compound is dissolved,
(Ii) a method of physically mixing a diimine compound and a salt without using a solvent,
And the like.

Further, the method for extracting the complex from the mixture of the diimine compound and iron is not particularly limited, for example,
(A) a method in which a solvent is distilled off when a solvent is used in the mixture, and a solid is filtered off;
(B) a method of filtering off a precipitate generated from the mixture,
(C) a method of adding a poor solvent to the mixture, purifying the precipitate, and filtering the precipitate;
(D) a method of directly removing the solvent-free mixture,
And the like. Thereafter, a washing treatment with a solvent capable of dissolving the unreacted diimine compound, a washing treatment with a solvent capable of dissolving the unreacted iron salt, a recrystallization treatment using an appropriate solvent, or the like may be performed. Examples of the solvent capable of dissolving the diimine compound include ether, tetrafudrofuran, benzene, toluene, xylene, cyclohexane, methylcyclohexane and the like. Examples of the solvent capable of dissolving the iron salt include alcohol solvents such as methanol, ethanol, and isopropanol, and tetrahydrofuran.

Examples of iron salts include iron (II) chloride, iron (III) chloride, iron (II) bromide, iron (III) bromide, iron (II) acetylacetonate, iron (III) acetylacetonate, Iron (II) acetate, iron (III) acetate and the like can be mentioned. Those having a ligand such as a solvent and water may be used as these salts. Among these, salts of iron (II) are preferred, and iron (II) chloride is more preferred.

The solvent for bringing the diimine compound into contact with iron is not particularly limited, and any of a nonpolar solvent and a polar solvent can be used. Examples of the nonpolar solvent include hydrocarbon solvents such as hexane, heptane, octane, benzene, toluene, xylene, cyclohexane, and methylcyclohexane. Examples of the polar solvent include a polar protic solvent such as an alcohol solvent and a polar aprotic solvent such as tetrahydrofuran. Examples of the alcohol solvent include methanol, ethanol, isopropyl alcohol and the like. In particular, when the mixture is used as a catalyst as it is, it is preferable to use a hydrocarbon solvent that does not substantially affect olefin polymerization.

混合 In addition, the mixing ratio of the diimine compound and iron when they are brought into contact is not particularly limited. The molar ratio of the diimine compound / iron is preferably 0.2 / 1 to 5/1, more preferably 0.3 / 1 to 3/1, still more preferably 0.5 / 1 to 2/1, and particularly preferably. It is 1/1.

Both of the two imine sites in the diimine compound are preferably E-forms, but may include Z-form diimine compounds as long as they contain E-form diimine compounds. Since a diimine compound containing a Z-form is unlikely to form a complex with a metal, it can be easily removed in a purification step such as solvent washing after forming a complex in the system.

エチレン The ethylene polymerization catalyst containing the iron complex represented by the general formula (1) may further contain an organoaluminum compound in order to make the polymerization reaction proceed more efficiently. Examples of the organoaluminum compound include trialkylaluminum, methylaluminoxane and the like. The trialkylaluminum may be a trialkylaluminum having an alkyl group having 10 or less carbon atoms, or may be a trialkylaluminum having an alkyl group having 8 or less carbon atoms. Examples of such a trialkylaluminum include trimethylaluminum, triethylaluminum, triisobutylaluminum, tributylaluminum, trihexylaluminum, trioctylaluminum and the like. From the viewpoint of more effectively improving the catalyst efficiency, the trialkylaluminum preferably contains at least one selected from the group consisting of trimethylaluminum, triethylaluminum and triisobutylaluminum, and more preferably contains trimethylaluminum.

At this time, the content ratio of the iron complex represented by the general formula (1) and the organoaluminum compound is represented by a molar ratio where G is the number of moles of the iron complex and H is the number of moles of aluminum atoms of the organic aluminum compound. And preferably G: H = 1: 10 to 1: 1000, more preferably 1:10 to 1: 800, still more preferably 1:20 to 1: 600, and particularly preferably 1:20 to 1: 500. You may. Within the above range, it is possible to suppress the increase in cost while exhibiting more sufficient polymerization activity.

(4) When methylaluminoxane is used as the organoaluminum compound, a commercially available product diluted with a solvent can be used as the methylaluminoxane, and a product obtained by partially hydrolyzing trimethylaluminum in a solvent can also be used. Further, at the time of partial hydrolysis of trimethylaluminum, a modified methylaluminoxane co-hydrolyzed by coexisting a trialkylaluminum other than trimethylaluminum such as triisobutylaluminum can also be used. Further, when unreacted trialkylaluminum remains during the above partial hydrolysis, the unreacted trialkylaluminum may be removed by distillation under reduced pressure or the like. Alternatively, a modified methylaluminoxane obtained by modifying methylaluminoxane with an active proton compound such as phenol or a derivative thereof may be used.

When trimethylaluminum and methylaluminoxane are used in combination as the organoaluminum compound, the content ratio of trimethylaluminum and methylaluminoxane in the ethylene polymerization catalyst is represented by the molar number of trimethylaluminum H ₁ and the molar number of aluminum atoms in methylaluminoxane. When H ₂ is used, the molar ratio is preferably H ₁ : H ₂ = 100: 1 to 1: 100, more preferably 50: 1 to 1:50, and even more preferably 10: 1 to 1:10. Within the above range, it is possible to suppress the factor of cost increase while expressing more sufficient catalyst efficiency.

The ethylene polymerization catalyst containing the iron complex represented by the general formula (1) may further contain a boron compound as an optional component.

The boron compound has a function as a cocatalyst for further improving the catalytic activity of the iron complex represented by the general formula (1) in the ethylene polymerization reaction.

Examples of the boron compound include an aryl boron compound such as trispentafluorophenylborane. Further, as the boron compound, a boron compound having an anionic species can be used. For example, aryl borates such as tetrakis pentafluorophenyl borate and tetrakis (3, 5-trifluoromethyl phenyl) borate are exemplified. Specific examples of aryl borates include lithium tetrakis pentafluorophenyl borate, sodium tetrakis pentafluorophenyl borate, N, N-dimethylanilinium tetrakis pentafluorophenyl borate, trityl tetrakis pentafluorophenyl borate, lithium tetrakis (3,5-tri Fluoromethylphenyl) borate, sodium tetrakis (3,5-trifluoromethylphenyl) borate, N, N-dimethylaniliniumtetrakis (3,5-trifluoromethylphenyl) borate, trityltetrakis (3,5-trifluoromethyl) Phenyl) borate and the like. Among them, N, N-dimethylanilinium tetrakispentafluorophenyl borate, trityl tetrakis pentafluorophenyl borate, N, N-dimethylanilinium tetrakis (3,5-trifluoromethylphenyl) borate or trityl tetrakis (3,5 (Trifluoromethylphenyl) borate is preferred. These boron compounds can be used alone or in combination of two or more.

In the ethylene polymerization catalyst, when an organic aluminum compound and a boron compound are used in combination, the content ratio of the organic aluminum compound and the boron compound is determined by the molar ratio when the number of moles of the organic aluminum compound is H and the number of moles of the boron compound is J. Preferably, H: J = 1000: 1 to 1: 1, more preferably 800: 1 to 2: 1, and still more preferably 600: 1 to 10: 1. Within the above range, it is possible to suppress the increase in cost while expressing more sufficient catalyst efficiency.

The ethylene polymerization catalyst containing the iron complex represented by the general formula (1) is further represented by the following general formula (2) from the viewpoint of securing more sufficient catalytic efficiency by suppressing the deactivation of the iron complex. (Hereinafter sometimes referred to as a ligand).

In the formula (2), R ″ represents a hydrocarbyl group having 1 to 6 carbon atoms or an aromatic group having 6 to 12 carbon atoms, and a plurality of R ″ s in the same molecule may be the same or different; “″ Represents a free radical having 0 to 6 carbon atoms having an oxygen atom and / or a nitrogen atom, and a plurality of R ″ ″ s in the same molecule may be the same or different.

In the formula (2), a plurality of R ″ and R ″ ″ in the same molecule may be the same or different, but may be the same from the viewpoint of simplifying the synthesis of the compound.

リガンド Specific examples of such a ligand include compounds represented by the following formulas (2a) to (2d). These ligands can be used alone or in combination of two or more.

Further, in the iron complex represented by the general formula (1) and the compound represented by the general formula (2), R in the general formula (1), R ″ in the general formula (2), and R ′ in 1) and R ″ ′ in general formula (2) may be the same or different, but from the viewpoint of maintaining the same performance as the iron complex represented by general formula (1), Preferably they are identical.

場合 When the above-mentioned ligand is contained in the ethylene polymerization catalyst according to the present embodiment, the content ratio of the iron complex and the ligand is not particularly limited. The ligand / iron complex ratio is preferably a molar ratio of 1/100 to 100/1, more preferably 1/50 to 50/1, further preferably 1/10 to 10/1, and particularly preferably 1/5. ５5/1, very preferably 1/3 to 3/1. When the ratio of ligand / iron complex is 1/100 or more, the catalyst efficiency can be increased by suppressing the deactivation of the iron complex. When the ratio is 100/1 or less, the effect of adding the ligand is exhibited. Costs can be reduced.

The method for producing the above ethylene polymerization catalyst is not particularly limited. For example, when the ethylene polymerization catalyst contains the iron complex represented by the above general formula (1) and the organoaluminum compound, the general formula (1) A method of adding and mixing a solution containing an organoaluminum compound to a solution containing an iron complex represented by the formula, and adding and mixing a solution containing an iron complex represented by the general formula (1) to a solution containing the organoaluminum compound And the like. Further, for example, when the above-mentioned boron compound and ligand are further included in addition to the iron complex and the organoaluminum compound represented by the general formula (1), all of these components may be brought into contact at once. However, they may be contacted in any order. As a method for producing the ethylene polymerization catalyst according to the present embodiment, for example,
(A) A method of mixing a solution containing an iron complex represented by the general formula (1) and a solution containing a boron compound, and then bringing the solution into contact with an organoaluminum compound (B) An iron complex represented by the general formula (1) (C) a method of mixing a solution containing a boron compound and a solution containing an organoaluminum compound, and then contacting the solution containing a boron compound with a solution containing an organoaluminum compound. (D) a method of mixing a solution containing an iron complex represented by the general formula (1) and a solution containing a ligand, and then contacting the solution with an organoaluminum compound (E). A) mixing a solution containing an organoaluminum compound and a solution containing an organoaluminum compound, and then contacting the ligand (F) mixing a solution containing an organoaluminum compound with a solution containing a ligand And then contacting the iron complex represented by the general formula (1) with the solution containing the iron complex represented by the general formula (1) and the boron compound. (H) A solution containing an iron complex represented by the general formula (1) is mixed with a solution containing a boron compound, and then a solution containing a ligand is added. , Mixing and then contacting the organoaluminum compound (I) After mixing the solution containing the iron complex represented by the general formula (1) and the solution containing the organoaluminum compound, a solution containing the boron compound is added, Mixing and then contacting the ligand (J) After mixing the solution containing the iron complex represented by the general formula (1) and the solution containing the organoaluminum compound, the solution containing the ligand is added and mixed. Then, a method of contacting a boron compound (K) After mixing a solution containing an iron complex represented by the general formula (1) and a solution containing a ligand, a solution containing an organoaluminum compound is added and mixed, and then the boron compound is mixed. (L) After mixing a solution containing an iron complex represented by the general formula (1) and a solution containing a ligand, a solution containing a boron compound is added and mixed, and then an organoaluminum compound is brought into contact. Method (M) A method comprising mixing a solution containing a boron compound and a solution containing an organoaluminum compound, adding and mixing a solution containing an iron complex represented by the general formula (1), and then contacting the ligand (N ) A solution containing a boron compound and a solution containing an organoaluminum compound are mixed, a solution containing a ligand is added and mixed, and then an iron complex represented by the general formula (1) (O) After mixing a solution containing a boron compound and a solution containing a ligand, a solution containing an iron complex represented by the general formula (1) is added and mixed, and then the organoaluminum compound is contacted. Method (P) A method of mixing a solution containing a boron compound and a solution containing a ligand, adding and mixing a solution containing an organoaluminum compound, and then contacting the iron complex represented by the general formula (1) (Q A) a method of mixing a solution containing an organoaluminum compound and a solution containing a ligand, adding and mixing a solution containing an iron complex represented by the general formula (1), and then contacting the boron compound. After mixing a solution containing a compound and a solution containing a ligand, a solution containing a boron compound is added, mixed, and then contacted with an iron complex represented by the general formula (1) ( A) contacting a solution containing an iron complex represented by the general formula (1) with a boron compound, then adding and mixing a solution containing an organoaluminum compound (T) iron complex represented by the general formula (1) After contacting the boron compound with the solution containing trimethylaluminum, adding and mixing a solution containing trimethylaluminum, and bringing the solution into contact with methylaluminoxane.

Ethylene oligomer means a homopolymer of ethylene or a copolymer of ethylene and α-olefin having a number average molecular weight (Mn) of 10,000 or less. The Mn of the ethylene oligomer obtained in the polymerization step can be appropriately adjusted according to its use. However, when the ethylene oligomer is used as a raw material such as a lubricating oil, the Mn is preferably 200 to 5000, more preferably 300 to 4000. , 350 to 3000 are more preferred. The dispersity is a ratio between the weight average molecular weight (Mw) and Mn, and is expressed as Mw / Mn. For example, preferably 1.0 to 5.0, more preferably 1.1 to 3.0. 0. For example, the Mn and Mw of the ethylene oligomer can be determined as polystyrene conversion amounts based on a calibration curve created from standard polystyrene using a GPC apparatus.

Ethylene oligomers usually include linear hydrocarbon compounds. The content of the linear hydrocarbon compound in the ethylene oligomer is not particularly limited, but is, for example, preferably 40% by mass or more, more preferably 50% by mass or more, and still more preferably 60% by mass or more based on the total amount of the ethylene oligomer. It is. The upper limit of the content of the linear hydrocarbon compound is not particularly limited, and is, for example, usually 100% by mass or less, preferably 90% by mass or less, and more preferably 85% by mass or less.

In the constitution of the hydrocarbon compound in the ethylene oligomer, the content of the hydrocarbon compound having an even number of carbon atoms is preferably 80% by mass or more, more preferably 90% by mass or more, based on the total amount of the ethylene oligomer. From the viewpoint of more effectively improving the viscosity-temperature characteristics and traction coefficient of the obtained isomerized oil, it is more preferable that the isomerized oil does not substantially contain a hydrocarbon compound having an odd number of carbon atoms.

The content of the above-mentioned linear hydrocarbon compound means a value obtained by performing a gas chromatography analysis on the ethylene oligomer under the following conditions, and measuring and calculating the ratio of the linear hydrocarbon compound in the total amount of the ethylene oligomer. . At the time of measurement, a mixed sample of normal paraffin having 5 to 50 carbon atoms was used as a standard sample, and each of the above ratios was the sum of the peak area value corresponding to normal paraffin to the total peak area value of the chromatogram. It is calculated as a percentage. Here, in the case of hydrocarbon compounds having the same carbon number, since the hydrocarbon compound having the highest boiling point (longest distillation time) is normal paraffin, the standard sample was measured when calculating the carbon number. The peak present between the peak corresponding to the distillation time of normal paraffin having n carbon atoms and the peak corresponding to the distillation time of normal paraffin having n-1 carbon atoms is n And normal paraffin and non-normal paraffin having the same number of carbon atoms are distinguished from each other.
(Gas chromatography conditions)
Column: Liquid phase non-polar column (length: 25 mm, inner diameter: 0.3 mmφ, liquid phase film thickness: 0.1 μm)
Heating conditions: 50 to 400 ° C (heating rate: 10 ° C / min)
Carrier gas: helium (linear velocity: 40 cm / min)
Split ratio: 90 / l
Sample injection volume: 0.5 μL (injection volume of sample diluted 20 times with carbon disulfide)
Detector: Flame ionization type detector (FID)

The content of the hydrocarbon compound having an even number of carbon atoms was determined by analyzing the ethylene oligomer contained in the polymerization mixture by electrolytic desorption mass spectrometry under the following conditions, and determining the ethylene content from the mass number of the obtained chromatogram. It means a value obtained by calculating the ratio of the hydrocarbon compound having an even number of carbon atoms in the total amount of the oligomer.
(Electrodesorption mass spectrometry conditions)
Equipment: JEOL JMS-T300GC
Ionization method: FD (Field Desorption)
Ion source temperature: room temperature Counter electrode voltage: -10 kV
Emitter current: 6.4 mA / min
Spectrum recording interval: 0.4 sec
Measurement mass range: m / z 35 to 1600

The polymerization mixture containing the ethylene oligomer obtained in the polymerization step is subjected to the first distillation step described below.However, the ethylene oligomer may be taken out from the obtained polymerization mixture and then subjected to the first distillation step, The mixture may be concentrated and subjected to the first distillation step as a concentrate having an increased concentration of ethylene oligomer. It is preferable to concentrate the polymerization mixture in order not to send a solvent or the like which is not a raw material of the lubricating base oil to the isomerization step described below. Examples of a method of concentrating the polymerization mixture include a method of concentrating the polymerization mixture with a concentrator such as a flash tank.

揮発 The volatile component obtained by concentrating the polymerization mixture with a concentrator usually contains unreacted ethylene, a polymerization solvent, and other light oligomers. The solvent is preferably recovered by distillation or the like and reused, and the other fractions can be sent to a decomposition purification step to be decomposed into ethylene and reused. When most of the volatile components are ethylene, it can be reused as ethylene without being sent to the decomposition and purification step. At that time, impurities such as butene that can be generated by the polymerization reaction are mixed and accumulated in the system.Therefore, when recovering ethylene, it is necessary to discharge a part of the system outside the system and keep the amount of impurities constant. , Leading to stable polymerization. Ethylene containing impurities discharged out of the system can be returned to the decomposition and purification step.

(First distillation step)
In the first distillation step, the polymerization mixture is fractionated by distillation into a lubricating oil fraction and a fraction other than the lubricating oil fraction. By passing through the first distillation step, it becomes possible not only to remove excess polymer generated in the above-mentioned polymerization step and to improve the efficiency of the isomerization reaction described later, but also to remove polymerization catalyst residues and the like.

The boiling point range of the lubricating oil fraction obtained in the first distillation step is, for example, a fraction having a boiling point range of 250 to 500 ° C. Furthermore, when isomerized oil corresponding to 70 Pale, SAE10, VG6, etc. obtained in each step described later is efficiently obtained, the boiling point range of the lubricating oil fraction obtained in the first distillation step is set as follows. can do.
Isomerized oil corresponding to 70 Pale: a fraction having a boiling range of 300 to 460 ° C. Isomerized oil corresponding to SAE10: a fraction having a boiling range of 360 to 500 ° C. Isomerized oil corresponding to VG6: a fraction having a boiling range of 250 to 440 ° C. For example, a boiling point range of 250 to 500 ° C. means that the initial boiling point and end point are in the range of 250 to 500 ° C.

The distillation conditions in the first distillation step are not particularly limited as long as the target lubricating oil fraction can be fractionated from the polymerization mixture containing the ethylene oligomer. For example, the first distillation step may be a step of fractionation by vacuum distillation, or may be a step of fractionation by combining atmospheric distillation (or distillation under pressure) and vacuum distillation. Further, for example, it may be fractionated as a single fraction, or may be fractionated as a plurality of fractions according to the viscosity grade.

留 Examples of the fraction other than the lubricating oil fraction include a solvent and a fraction containing unreacted ethylene. Fractions other than the lubricating oil fraction may be purified and reused in the polymerization step, if desired, or may be returned to the decomposition and purification step described above. In addition, components other than unreacted ethylene can be returned to the decomposition and purification step, and can also be separated and used as basic chemicals if desired.

(Isomerization step)
In the isomerization step, the lubricating oil fraction is hydroisomerized in the presence of a hydroisomerization catalyst to obtain a reaction mixture containing the isomerized oil. More specifically, the isomerization step is a step in which an ethylene oligomer is brought into contact with a hydroisomerization catalyst in the presence of hydrogen (molecular hydrogen) to hydroisomerize the ethylene oligomer. The hydroisomerization here includes, in addition to isomerization of normal paraffin to isoparaffin, conversion of olefin to paraffin by hydrogenation and the like.

The hydroisomerization catalyst may contain either a crystalline or amorphous material. As the crystalline material, for example, a molecular sieve having a 10- or 12-membered ring passage mainly containing aluminosilicate (zeolite) or silicoaluminophosphate (SAPO) can be mentioned. Specific examples of the zeolite include ZSM-22, ZSM-23, ZSM-35, ZSM-48, ZSM-57, ferrierite, ITQ-13, MCM-68, MCM-71 and the like. ECR-42 is an example of an aluminophosphate. Examples of molecular sieves include zeolite beta, and MCM-68. Among them, it is preferable to use one or more selected from ZSM-48, ZSM-22 and ZSM-23, and ZSM-48 is particularly preferable. The molecular sieve is preferably in the hydrogen form. The reduction of the hydroisomerization catalyst can occur in situ at the time of hydroisomerization, but the hydroisomerization catalyst which has been subjected to a reduction treatment in advance may be subjected to hydroisomerization.

非晶質 Examples of the amorphous material for the hydroisomerization catalyst include alumina doped with a Group 3 metal, fluorinated alumina, silica-alumina, and fluorinated silica-alumina.

Preferred embodiments of the hydroisomerization catalyst include those that are bifunctional, ie, equipped with a metal hydrogenation component that is at least one Group 6 metal, at least one Group 8-10 metal, or a mixture thereof. Can be Preferred metals are Group 9-10 noble metals such as Pt, Pd or mixtures thereof. The loading of these metals is preferably 0.1 to 30% by mass based on the total amount of the catalyst. Examples of the method for preparing the catalyst and mounting the metal include an ion exchange method and an impregnation method using a decomposable metal salt.

In the case of using a molecular sieve, the molecular sieve may be combined with a binder material having heat resistance under hydroisomerization conditions, or may be used without a binder (self-bonding). Examples of the binder material include a combination of two components with other metal oxides such as silica, alumina, silica-alumina, silica-titania, magnesia, thoria, zirconia, silica-alumina-tria, silica-alumina-magnesia, etc. And inorganic oxides such as combinations of acid components of the oxides. The amount of the molecular sieve in the hydroisomerization catalyst is preferably from 10 to 100% by mass, more preferably from 35 to 100% by mass, based on the total amount of the catalyst. The hydroisomerization catalyst is formed by a method such as spray drying and extrusion. The hydroisomerization catalyst can be used in a sulfided or non-sulfided form, with the sulfided form being preferred.

Regarding the hydroisomerization conditions, the temperature is preferably 250 ° C. to 400 ° C., more preferably 275 ° C. to 350 ° C., and the hydrogen partial pressure is preferably 791 kPa to 20786 kPa (100 psig to 3000 psig), more preferably 1480 kPa to 17339 kPa ( 200 psig ~ a ^2500psig), 0.1hr ^-1 ~ 10hr -1 liquid hourly space velocity is preferably, more preferably ^{0.1 hr} -1 ~ ^{5 hr -1,} a hydrogen / oil ratio is preferably ^{45 m} 3 / ^{m 3} ^{^{~ 1780m 3 / m 3 (250scf}} / B ~ 10000scf / B), and more preferably ^{^{^{^{89m 3 / m 3 ~ 890m 3}}}} / m 3 (500scf / B ~ 5000scf / B). Note that the above conditions are merely examples, and it is preferable that the hydroisomerization conditions be appropriately selected according to differences in raw materials, catalysts, equipment, and the like.

Through the isomerization step, a reaction mixture containing an isomerized oil in which ethylene oligomer is isomerized to isoparaffin can be obtained.

(Second distillation step)
In the second distillation step, the reaction mixture obtained in the isomerization step is fractionated by distillation into a lubricating base oil and a fraction other than the lubricating base oil. The fraction other than the lubricating base oil is generally a light fraction lighter than the lubricating base oil and a heavy fraction heavier than the lubricating base oil. Such a fraction may be, for example, a normal pressure distillation (or distillation under pressure) for fractionating a light fraction from a reaction mixture containing the isomerized oil, and a desired lubricating oil base from the bottom oil of the normal pressure distillation. Distillation under reduced pressure to fractionate the oil fraction.

The distillation conditions in the second distillation step are not particularly limited as long as the target lubricating base oil can be fractionated from the reaction mixture. For example, the second distillation step may be a step of fractionation by vacuum distillation, or may be a step of fractionation by combining atmospheric distillation (or distillation under pressure) and vacuum distillation. Further, the lubricating base oil may be fractionated as a single fraction, or may be fractionated as a plurality of fractions according to the viscosity grade.

In the fractionation of the lubricating base oil, a plurality of cut points are set and distillation under reduced pressure is performed to obtain a plurality of lubricating base oil fractions according to the purpose. For example, in order to obtain a lubricating base oil equivalent to 70 Pale suitable as a lubricating base oil for ATF and shock absorbers, a kinematic viscosity at 100 ° C. of 2.7 mm ² / s is set as a target value, and a boiling point range at normal pressure is set. A method for recovering a fraction at 330 ° C. to 410 ° C .; a kinematic viscosity at 100 ° C. to obtain a lubricating base oil corresponding to SAE-10, which is suitable as a lubricating base oil for engine oil meeting API Group III standards. A method of recovering a fraction having a boiling point range of 410 ° C. to 460 ° C. at normal pressure with a target value of 4.0 mm ² / s; equivalent to SAE-20 suitable as a lubricating base oil for various gear oils and hydraulic oils to obtain a lubricating base oil, as a target value of the kinematic viscosity 5.6 mm ² / s at 100 ° C., the method boiling range at atmospheric pressure to recover a fraction of 460 ℃ ~ 500 ℃; to VG6 To obtain the equivalent lubricating base oil, as a target value of the kinematic viscosity 2.0 mm 2 / ^s at 100 ° C., and a method of boiling range to recover a fraction of 330 ° C. or less and the like. The SAE viscosity means a standard defined by Society of Automated Engineers.

For the second distillation step the viscosity grade of the lubricating base oil obtained through the, is not particularly limited, kinematic viscosity at 100 ° C. is preferably 1.5 mm 2 / ^s or more, more preferably 1.8 mm ² / S or more. On the other hand, the upper limit of the kinematic viscosity at 100 ° C. is not particularly limited, but is preferably 20 mm ² / s or less, more preferably 11 mm ² / s or less, and particularly preferably 5.0 mm ² / s or less.

Further, as described above, when obtaining a plurality of lubricating base oil fractions according to the purpose by setting a plurality of cut points in the second distillation step, the kinematic viscosity of the obtained lubricating base oil at 100 ° C. Preferably, it is as follows.
(I) a lubricating base oil having a kinematic viscosity at 100 ° C. of 1.5 mm ² / s or more and less than 2.3 mm ² / s, more preferably 1.8 mm to 2.1 mm ² / s (II) a kinematic viscosity at 100 ° C. There 2.3 mm ² / s or more 3.0mm less than ² / s, more preferably 2.4 ~ 2.8mm ² / s lubricating base oil (III) a kinematic viscosity at 100 ° C. is 3.0 ~ 20 mm ² / s, more preferably 3.2 to 11 mm ² / s, still more preferably 3.5 to 5.0 mm ² / s, particularly preferably 3.6 to 4.0 mm ² / s.

粘度 The viscosity index of the lubricating base oil can be appropriately selected according to its viscosity grade. For example, the viscosity index of the lubricating base oil (I) is preferably 105 to 150, more preferably 110 to 140, and still more preferably 115 to 135. The viscosity index of the lubricating base oil (II) is preferably from 120 to 160, more preferably from 125 to 150, and still more preferably from 130 to 150. The viscosity index of the lubricating base oil (III) is preferably 140 to 180, more preferably 145 to 170, and still more preferably 150 to 165. By setting the viscosity index within the above range, excellent viscosity-temperature characteristics can be secured, so that a lubricating base oil excellent in energy saving can be obtained.

The density (ρ ₁₅ , unit: g / cm ³ ) of the lubricating base oil at 15 ° C. can be appropriately selected according to its viscosity grade. For example, [rho ₁₅ for the lubricating base oil (I) is preferably from 0.82 g / cm ³ or less, more preferably 0.81 g / cm ³ or less, more preferably 0.80 g / cm ³ or less, particularly preferably 0.79 g / cm ³ or less. [Rho ₁₅ of the lubricating base oils (II) and (III), preferably 0.84 g / cm ³ or less, more preferably 0.83 g / cm ³ or less, more preferably is 0.82 g / cm ³ or less . By setting the density at 15 ° C. within the above range, it is possible to obtain a lubricating base oil having excellent viscosity-temperature characteristics and heat / oxidation stability, as well as excellent volatilization prevention properties and low-temperature viscosity characteristics. When an additive is added to the mixture, the effect of the additive can be sufficiently ensured.

流動 The pour point of the lubricating base oil can be appropriately selected according to its viscosity grade. For example, the pour point of the lubricating base oil (I) is preferably −10 ° C. or lower, more preferably −20 ° C. or lower, and still more preferably −30 ° C. or lower. The pour point of the lubricating base oil (II) is preferably −10 ° C. or lower, more preferably −15 ° C. or lower, and still more preferably −20 ° C. or lower. The pour point of the lubricating base oil (III) is preferably -10 ° C or lower, more preferably -15 ° C or lower. By setting the pour point of the lubricating base oil within the above numerical range, a low-temperature fluidity can be sufficiently ensured, and a lubricating base oil excellent in energy saving can be obtained.

The cloud point of the lubricating base oil depends on its viscosity grade. For example, the lubricating base oil (I) has a cloud point of preferably -15 ° C or lower, more preferably -17.5 ° C or lower. . The cloud point of the lubricating base oil (II) is preferably -10 ° C or lower, more preferably -12.5 ° C or lower. The cloud point of the lubricating base oil (III) is preferably -10 ° C or lower. By setting the cloud point of the lubricating base oil within the above numerical range, the lubricating base oil can sufficiently secure low-temperature fluidity, which is preferable from the viewpoint of energy saving.

Further, when a gas chromatographic analysis is performed on the lubricating base oil, the carbon number distribution of the hydrocarbon compound contained in the lubricating base oil can be appropriately selected according to its viscosity grade. For example, the carbon number distribution in the lubricating base oil (I) is preferably 10 to 35, more preferably 15 to 30. The carbon number distribution in the lubricating base oil (II) is preferably from 12 to 40, more preferably from 15 to 35. The carbon number distribution in the lubricating base oil (III) is preferably 15 to 50, more preferably 18 to 45.

When a gas chromatographic analysis is performed on a lubricating base oil, the average carbon number of the hydrocarbon compound contained in the lubricating base oil can be appropriately selected according to its viscosity grade. For example, the average carbon number in the lubricating base oil (I) is preferably 15 to 25, more preferably 18 to 22. The average carbon number in the lubricating base oil (II) is preferably 15 to 30, more preferably 20 to 25. The average carbon number in the lubricating base oil (III) is preferably 20 to 40, more preferably 25 to 30. By setting the carbon number distribution and / or the average carbon number within the above numerical range, a lubricating base oil having excellent energy saving properties can be obtained.

Since the lubricating base oil obtained by the method for producing a lubricating base oil according to the present embodiment is obtained from the above-mentioned ethylene oligomer, a hydrocarbon compound having an even number of carbon atoms and an odd number of carbon atoms are used. The balance of the content of hydrocarbon compounds is not uniform. In the configuration of the hydrocarbon compound contained in the lubricating base oil, the specific content of the hydrocarbon compound having an even number of carbon atoms is not particularly limited, but based on the total amount of the lubricating base oil, for example, It is preferably at least 60% by mass, more preferably at least 70% by mass, further preferably at least 80% by mass, particularly preferably at least 85% by mass.

The carbon number distribution and the average carbon number described above are values obtained by performing mass spectrometry on the isomerized oil. FIG. 1 is an FD-MS chromatogram of the isomerized oil obtained in Example 1. For example, a peak near MS 338 (C ₂₄ H ₅₀ ) is C24, and a peak near MS 310 (C ₂₂ H ₄₆ ) is C22. And MS324 _(C 23 _{H 48)} peak in the vicinity is C23. The average carbon number is determined by adding these neighboring ion intensities to determine the content of each carbon number and dividing them by the total amount. From the start and end of the chromatogram, the carbon number distribution is determined.

The content of the hydrocarbon compound having an even number of carbon atoms is determined by analyzing the isomerized oil by mass spectrometry, and measuring and calculating the ratio of the hydrocarbon compound having an even number of carbon atoms in the total amount of the isomerized oil. Means the value of As an analysis method, electrolytic desorption mass spectrometry based on the following conditions can be preferably adopted.
(Electrodesorption mass spectrometry conditions)
Equipment: JEOL JMS-T300GC
Ionization method: FD (Field Desorption)
Ion source temperature: room temperature Counter electrode voltage: -10 kV
Emitter current: 6.4 mA / min
Spectrum recording interval: 0.4 sec
Measurement mass range: m / z 35 to 1600

The lubricating base oil obtained above can be preferably used as a lubricating base oil for various uses. Specific applications of the lubricating base oil include, for example, lubricating oils used in internal combustion engines such as gasoline engines for passenger cars, gasoline engines for motorcycles, diesel engines, gas engines, engines for gas heat pumps, marine engines, and power generation engines. (Lubricating oil for internal combustion engines), lubricating oil (oil for driving transmission devices) used in drive transmission devices such as automatic transmissions, manual transmissions, continuously variable transmissions, final reduction gears, etc., and hydraulic pressure for shock absorbers, construction machinery, etc. Hydraulic hydraulic oil, compressor oil, turbine oil, industrial gear oil, refrigerating machine oil, rust preventive oil, heat transfer oil, gas holder seal oil, bearing oil, paper machine oil, machine tool oil, machine tool oil, sliding guide surface used in equipment Oil, electric insulating oil, cutting oil, press oil, rolling oil, heat treatment oil and the like.

In the above applications, the lubricating base oil obtained by the production method according to the present embodiment may be used alone as the lubricating base oil, or the lubricating base oil may be used as one of other base oils. It may be used in combination with two or more species. When other base oils are used in combination, the ratio of the lubricating base oil obtained by the production method according to the present embodiment to the mixed base oils is preferably 30% by mass, and 50% by mass. More preferably, it is more preferably 70% by mass or more.

The other base oil used in combination with the lubricating base oil obtained by the production method according to the present embodiment is not particularly limited, and examples of the mineral base oil include API group I to group III. Mineral oil and the like. In addition, each group of API classification means the thing according to the classification of the lubricating oil grade of American Petroleum Institute (API (American @ Pertoleum @ Institute)).

Synthetic base oils include poly-α-olefin or hydride thereof, isobutene oligomer or hydride thereof, isoparaffin, alkylbenzene, alkylnaphthalene, diester (ditridecyl glutarate, di-2-ethylhexyl adipate, diisodecyl adipate, ditride). Decyl adipate, di-2-ethylhexyl sebacate, etc.), polyol esters (trimethylolpropane caprylate, trimethylolpropaneperargonate, pentaerythritol 2-ethylhexanoate, pentaerythritol pelargonate, etc.), polyoxyalkylene glycol, dialkyl Examples thereof include diphenyl ether and polyphenyl ether, and among them, poly α-olefin is preferable. The poly-α-olefin is typically an oligomer or co-oligomer of an α-olefin having 2 to 32, preferably 6 to 16 carbon atoms (eg, 1-octene oligomer, decene oligomer, ethylene-propylene cooligomer) and the like. Hydride.

The method for producing the poly-α-olefin is not particularly limited. For example, a Friedel-Crafts catalyst containing a complex of aluminum trichloride or boron trifluoride with water, alcohol (ethanol, propanol, butanol, etc.), carboxylic acid or ester And a method of polymerizing an α-olefin in the presence of a polymerization catalyst such as

各種 Further, if necessary, various additives can be blended with the lubricating base oil obtained by the production method according to the present embodiment or a mixed base oil of the lubricating base oil and another base oil. Such additives are not particularly limited, and any additives conventionally used in the field of lubricating oils can be blended. Specific examples of such lubricating oil additives include antioxidants, ashless dispersants, metal detergents, extreme pressure agents, antiwear agents, viscosity index improvers, pour point depressants, friction modifiers, oil agents , A corrosion inhibitor, a rust inhibitor, a demulsifier, a metal deactivator, a seal swelling agent, an antifoaming agent, and a coloring agent. One of these additives may be used alone, or two or more thereof may be used in combination.

留 The fraction other than the lubricating base oil obtained in the second distillation step includes, for example, a fraction lighter than the lubricating base oil and a fraction heavier than the lubricating base oil. These fractions can be returned to the cracking and refining step and used as feedstock.

In the method for producing a lubricating base oil according to the present embodiment, a fraction other than the lubricating oil fraction obtained in the above-described first distillation step and / or a lubricating base oil obtained in the second distillation step A fraction other than the above is returned to the cracking and refining step as a part of the feedstock oil. Among them, the fraction returned to the cracking and refining step is preferably a fraction other than the lubricant base oil obtained in the second distillation step, and the fraction is a lighter fraction lighter than the lubricant base oil. Is more preferable.

The fraction other than the lubricating oil fraction obtained in the first distillation step and the fraction other than the lubricating oil base oil obtained in the second distillation step respectively separate the polymerization mixture and the reaction mixture containing the ethylene oligomer. It is obtained by fixing. The ethylene oligomer is a hydrocarbon compound in which most of the constituent hydrocarbon compounds have an even number of carbon atoms. Therefore, in the fraction, the content balance between the hydrocarbon compound having an even number of carbon atoms and the hydrocarbon compound having an odd number of carbon atoms is not uniform. In the structure of the hydrocarbon compound contained in the fraction, the specific content of the hydrocarbon compound having an even number of carbon atoms is not particularly limited, but based on the total amount of the fraction, for example, preferably 50 It is less than 50% by mass, more preferably 45% by mass or less, and still more preferably 40% by mass or less.

So far, the preferred embodiment of the method for producing a lubricating base oil according to the present invention has been described. However, the present invention is not limited to the above-described embodiment, and various types generally employed in the production of a lubricating base oil are described. May be appropriately provided.

Next, a description will be given of a lubricating base oil manufacturing apparatus for implementing the method of manufacturing a lubricating base oil according to the present embodiment. FIG. 2 is a flowchart illustrating an example of a lubricating base oil manufacturing apparatus for performing the method of manufacturing a lubricating base oil according to one embodiment of the present invention.

The lubricating base oil producing apparatus 100 shown in FIG. 2 is configured to thermally decompose the feedstock introduced from the flow path L1 and to purify the obtained pyrolyzed product to obtain ethylene. A first reactor 20 for oligomerizing ethylene (cracked oil containing ethylene) supplied from the cracking and refining apparatus 10 through a flow path L2; and an ethylene oligomer supplied from the first reactor 20 through a flow path L3. A first distillation column 30 for fractionating the polymerization mixture containing the mixture into a lubricating oil fraction and a fraction other than the lubricating oil fraction, and converting the lubricating oil fraction supplied from the first distillation column 30 through the flow path L4 to hydrogen. The second reactor 40 to be isomerized and the isomerized oil (reaction mixture containing the isomerized oil) supplied from the second reactor 40 through the flow path L5 are mixed with the lubricating base oil and the non-lubricating base oil. The second fractionated fraction A distilling column 50, a flow path L4 'where a fraction other than the lubricating oil fraction obtained in the first distillation tower 30 is merged with the flow path L1, and / or a lubricating oil base oil obtained in the second distillation tower 50 And a flow path L6 for extracting the lubricating base oil obtained in the second distillation column 50.

形式 The types of the thermal decomposition purification device 10, the first reactor 20 and the second reactor 40 are not particularly limited. For example, a naphtha cracker is preferably used for the thermal decomposition purification device 10, a reactor containing an ethylene polymerization catalyst and a solvent is suitably used for the first reactor 20, and a second reactor 40 is used for the first reactor 20. A fixed bed flow reactor filled with a hydroisomerization catalyst is preferably used. In the lubricating base oil manufacturing apparatus 100, only one pyrolysis purification unit 10, the first reactor 20 and the second reactor 40 are arranged, respectively. The apparatus, the plurality of first reactors for the oligomerization reaction, and the plurality of second reactors for the hydroisomerization may be respectively arranged in series or in parallel. Further, the catalyst bed in the second reactor 40 may be single or plural.

In the first distillation column 30, for example, a light fraction from the top of the column, a solvent from the middle of the column, a lubricating oil fraction from the bottom of the column, and a heavy fraction from the bottom, The light fraction can be fractionated from the top of the 50 column, the lubricating base oil from the middle of the column, and the heavy fraction from the bottom of the column. Although a part or all of the solvent obtained in the distillation column 30 can be supplied to the thermal decomposition apparatus 10, it is preferable that the solvent be purified and reused as a polymerization solvent. Further, in the lubricating base oil manufacturing apparatus 100, only one single distillation column 30 and only one second distillation column 50 are arranged, but depending on the conditions of fractionation, a plurality of first distillation columns 30 and second distillation columns 50 are provided. And the plurality of second distillation columns may be arranged in series or in parallel, respectively.

Further, the lubricating base oil manufacturing apparatus 100 is configured to remove unreacted ethylene contained in the polymerization mixture supplied from the first reactor 20 downstream of the first reactor 20 and upstream of the first distillation column 30. A flash tank for recovery may be provided, or a deash tank for removing metal components such as a catalyst and a catalyst activator contained in the polymerization mixture may be provided. The unreacted ethylene recovered in the flash tank may be partially supplied to the pyrolysis purification device 10 or the first reactor 20 in some cases, and may be reused as ethylene. From the viewpoint of keeping the polymerization reactivity of the unreacted ethylene to be recovered constant, a bleeding step for discharging impurities out of the system may be provided in order to keep the ethylene purity in the recovered ethylene constant. Further, a solvent recovery and purification device may be provided before the first distillation column, and the recovered solvent can be reused as a polymerization reaction solvent.

Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the examples.

[Production Example 1: Synthesis of compound represented by formula (2a)]
2-methyl-4-methoxyaniline (2.0893 g, 15.3 mmol, manufactured by Tokyo Chemical Industry), 2,6-diacetylpyridine (1.2429 g, 7.6 mmol, manufactured by Tokyo Chemical Industry), Molecular Sieve 4A (5.0 g) Then, a catalytic amount of p-toluenesulfonic acid was dispersed in dry toluene (60 ml), and the mixture was stirred while heating and refluxing for 24 hours while removing water using a Dean-Stark water separator.

モ The molecular sieve was removed from the reaction solution by filtration and washed with toluene. The washing liquid and the filtered reaction liquid were mixed and concentrated to dryness to obtain a crude solid (2.8241 g). The crude solid (2 g) obtained here was weighed and washed with absolute ethanol (30 ml). The ethanol-insoluble solid was filtered off, and the insoluble solid was further washed with ethanol. The residual solid was sufficiently dried to obtain a compound represented by the following formula (2a) in a yield of 50%.

¹ H-NMR (600 MHz, CDCl ₃ ): 2.1 (s, 6H), 2.4 (s, 6H), 3.8 (s, 6H), 6.6 (m, 2H), 6.7. (M, 2H), 6.8 (m, 2H), 7.9 (m, 1H), 8.4 (m, 2H)
¹³ C-NMR (600 MHz, CDCl ₃ ): 16, 18, 56, 116, 119, 122, 125, 129, 137, 138, 143, 156, 167

[Production Example 2: Synthesis of compound represented by formula (1a)]
FeCl ₂ .4H ₂ O (0.2401 g, 1.2 mmol, manufactured by Kanto Chemical) was dissolved in dehydrated tetrahydrofuran (30 ml, manufactured by Aldrich), and the previously synthesized diimine compound (I) (0.4843 g, 1.2 mmol) Of tetrahydrofuran (10 ml) was added. The addition of the yellow diimine compound instantly resulted in a dark green tetrahydrofuran solution. Further, the mixture was stirred at room temperature for 2 hours. The solvent was evaporated from the reaction solution to dryness, and the precipitated solid was washed with dehydrated ethanol until the filtrate was colorless. Further, the washed solid was washed with dehydrated diethyl ether, and the solvent was removed to obtain an iron compound. The obtained iron compound was found to have 527.0820 (calculated value: 527.0831) by FD-MS, suggesting the structure of the following iron compound (1a).

[Production Example 3: Preparation of ethylene polymerization catalyst]
Under a nitrogen stream in a 500 ml eggplant flask, the compound represented by the formula (1a) obtained in Production Example 2 (42.2 mg) and one equivalent of trityltetrakispentafluorophenyl borate (73.8 mg) based on iron were added. It was dissolved in 200 ml of dry toluene to obtain a solution (A). A solution of trimethylaluminum (TMA) in an amount of 100 equivalents to the compound represented by the formula (1a) was added to the solution (A), followed by stirring for 5 minutes to obtain a solution (B) containing a catalyst. To the solution (B), a compound represented by the formula (1a) obtained in Production Example 1 was added as a ligand in an amount of 0.33 equivalent to the compound represented by the formula (2a), and then the ethylene polymerization catalyst was added. A solution (C) containing

<Manufacture of lubricating base oil>
[Example 1]
(Heat cracking of feedstock)
Hydrocarbons were thermally decomposed using a pyrolyzer (EGA / PY 3030D, Frontier Lab), which is a pyrolysis device, a gas chromatograph device, and a pyrolysis behavior evaluation device with a mass spectrometer. The gas generated by thermal decomposition was collected by a microjet cryotrap while cooling with liquid nitrogen, separated by gas chromatography, and qualitative and quantitative analysis was performed by mass spectrometry. The conditions of the thermal decomposition behavior evaluation device are as follows.

・ Pyrolyzer temperature: 750 ° C or 700 ° C
Residence time: 1 minute Gas chromatograph Inlet temperature: 250 ° C
Temperature rise: 40 ° C (hold 3 minutes) to 250 ° C (hold 20 ° C / minute, 30 minutes)
Column: Micropolar column (5% diphenyl, 95% dimethylpolysiloxane; length: 30 m, inner diameter: 0.25 mmφ, liquid phase film thickness: 1 μm)
Carrier gas: Helium (1 ml / min)
Split ratio: 100/1
・ Mass spectrometer Scan range: m / z 10 to 550
Scan rate: 2.7 scans / sec Ion source temperature: 230 ° C

ナ Normal octane (manufactured by Tokyo Chemical Industry, 1.3 mg) was pyrolyzed at 750 ° C. as a typical naphtha used as a feedstock oil. Separation by gas chromatography and mass spectrometry revealed that methane, ethylene, propylene, 1-butene, butadiene, 3-methyl-1-butene, 2-pentene, piperylene, isoprene, cyclopentadiene, cyclopentene, hexadiene, 1-hexene, cyclohexane Hexadiene, methylcyclopentadiene, benzene, etc. were detected as pyrolysis components. The obtained ethylene was 7.5% (gas chromatography area; the same applies hereinafter), propylene was 11.9%, and butadiene was 13.9%.

(Ethylene oligomerization reaction)
A 20 L autoclave equipped with an electromagnetic induction stirrer was sufficiently dried at 110 ° C. under reduced pressure in advance. Next, under a nitrogen stream, dry toluene (7.6 L) was introduced into the autoclave, and the temperature was adjusted to 0 ° C.

The solution (C) containing the ethylene polymerization catalyst prepared in Production Example 3 was added to the above-mentioned autoclave into which dry toluene had been introduced, and commercially available ethylene corresponding to high-purity ethylene purified from the pyrolysis component obtained above (large Nippon Sanso, industrial (> 99.5%)) was continuously introduced at 0 ° C. and 0.2 MPa. After 970 minutes, the introduction of ethylene was stopped, unreacted ethylene was removed, the ethylene in the autoclave was purged with nitrogen, and a very small amount of ethanol was added. The autoclave was opened, the contents were sequentially transferred to a 20 L evaporator, and the solvent was distilled off under reduced pressure to obtain a semi-solid oligomer. Such polymerization was repeated four times. A typical catalyst efficiency (CE) was 68875 {Poly kg / Fe} mol. The Mn of the oligomer (WAX1) obtained by mixing the four batches was 510, and the Mw / Mn was 1.7. Table 1 shows the results obtained by gas chromatography analysis and electrolytic desorption mass spectrometry for the content of normal paraffins and the content of hydrocarbon compounds having an even number of carbon atoms (even number of carbon atoms) of WAX1.

(Distillation of oligomer)
9293 g of the above-mentioned WAX1 was introduced into a 20 L three-necked flask, and the bottom temperature was changed from normal temperature to 380 ° C., the pressure was changed from normal pressure to 29 kPa, and simple distillation was performed to collect a boiling point fraction of 250 to 500 ° C. in terms of normal pressure. . 7,470 g of a fraction (a lubricating oil fraction) was collected, and the residue (a fraction other than the lubricating oil fraction) was 1,791 g. Mn of the lubricating oil fraction was 470, and Mw / Mn was 1.5. In addition, Mn of the residue was 2000, and Mw / Mn was 1.6.

残渣 The residue (0.8 mg) obtained above was pyrolyzed at 700 ° C. Separation by gas chromatography and mass spectrometry revealed that methane, ethylene, propylene, 1-butene, butadiene, 2-pentene, piperylene, isoprene, cyclopentadiene, cyclopentene, hexadiene, 1-hexene, cyclohexadiene, methylcyclopentadiene, benzene, etc. Was detected as a pyrolysis component. The obtained ethylene was 6.4%, propylene was 9.3%, and butadiene was 13.9%. It was shown that a fraction other than the lubricating oil fraction obtained by distillation of the oligomer could be recovered by thermal decomposition to recover sufficient ethylene again.

(Hydroisomerization reaction)
The lubricating oil fraction obtained above was treated with a zeolite-based hydroisomerization catalyst adjusted to have a noble metal content of 0.1 to 5% by mass at a reaction temperature of 330 ° C., a hydrogen partial pressure of 5 MPa, and a space velocity of 1. Hydroisomerization was performed under the condition of 0 LHSV to obtain isomerized oil 1.

(Distillation of isomerized oil)
The isomerized oil 1 obtained above was distilled under reduced pressure to obtain a lubricating base oil 1 equivalent to 70 Pale and a fraction other than the lubricating base oil 1. Table 2 shows the properties of the obtained lubricating base oil 1. In Table 2, “Carbon number distribution”, “Average carbon number” and “Even carbon number content” are obtained by performing gas chromatography analysis on the obtained lubricating base oil 1. The "traction coefficient" is a value measured using a steel ball and a steel disk as test pieces under the conditions of a load of 20 N, a test oil temperature of 25 ° C., a peripheral speed of 0.52 m / s, and a slip rate of 3% ( The same applies hereinafter.)

[Example 2]
The operation up to the oligomerization reaction of ethylene was performed in the same manner as in Example 1 to obtain an oligomer (WAX1).
(Distillation of oligomer)
5000 g of the above-mentioned WAX1 was introduced into a 20 L three-necked flask, and the bottom temperature was changed from normal temperature to 380 ° C., the pressure was changed from normal pressure to 29 kPa, and simple distillation was performed to collect a boiling point fraction of 300 to 440 ° C. in terms of normal pressure. .

(Hydroisomerization reaction)
The lubricating oil fraction obtained above was treated with a zeolite-based hydroisomerization catalyst adjusted to have a noble metal content of 0.1 to 5% by mass at a reaction temperature of 330 ° C., a hydrogen partial pressure of 5 MPa, and a space velocity of 1. Hydroisomerization was performed under the condition of 0 LHSV to obtain isomerized oil 2.

(Distillation of isomerized oil)
By distilling the isomerized oil 2 obtained above under reduced pressure, a lubricating base oil 2 equivalent to VG6 and a fraction other than the lubricating base oil 2 (a light fraction lighter than the lubricating base oil 2 and lubricating oil) A heavy fraction heavier than the oil base oil 2) was obtained. Table 2 shows the properties of the obtained lubricating base oil 2.

(4) The light fraction (0.8 mg) obtained above was pyrolyzed at 750 ° C. Separation by gas chromatography and mass spectrometry revealed that methane, ethylene, propylene, 1-butene, butadiene, 2-pentene, piperylene, isoprene, cyclopentadiene, cyclopentene, hexadiene, 1-hexene, cyclohexadiene, methylcyclopentadiene, benzene, etc. Was detected as a pyrolysis component. The obtained ethylene was 10.4%, propylene was 14.5%, and butadiene was 14.9%. It has been shown that a light fraction lighter than the lubricating base oil obtained by distillation of the isomerized oil can recover sufficient ethylene again by returning to the thermal cracking.

(4) The heavy fraction (1.2 mg) obtained above was pyrolyzed at 750 ° C. Separation by gas chromatography and mass spectrometry revealed that methane, ethylene, propylene, 1-butene, butadiene, 2-pentene, piperylene, isoprene, cyclopentadiene, cyclopentene, hexadiene, 1-hexene, cyclohexadiene, methylcyclopentadiene, benzene, etc. Was detected as a pyrolysis component. The obtained ethylene was 7.6%, propylene was 11.5%, and butadiene was 15.9%. It was shown that a heavy fraction heavier than the lubricating base oil obtained by distillation of the isomerized oil could be recovered by thermal decomposition to recover sufficient ethylene again.

(Effect of olefin on ethylene oligomerization reaction)
In the ethylene oligomerization reaction, the following test was conducted in order to examine the effect of the presence of the olefin on the catalytic efficiency of the ethylene polymerization catalyst.

[Reference example]
Under a nitrogen stream, a compound (1 μmol) represented by the formula (1a) and 1 equivalent of trityltetrakispentafluorophenylborate with respect to iron were dissolved in 20 ml of dry toluene in a 50 mL eggplant flask, and a solution (D) was obtained. did. To the solution (D), a trimethylaluminum (TMA) solution of 100 equivalents to the compound represented by the formula (1a) was added, and the mixture was stirred for 5 minutes to obtain a solution (E) containing a catalyst. Under a nitrogen stream, dry toluene (80 mL) was introduced into a 600 mL autoclave equipped with an electromagnetic induction stirrer which was sufficiently dried at 110 ° C. in advance under reduced pressure, and the temperature was adjusted to 25 ° C. The solution (E) was added to the autoclave into which dry toluene had been introduced, and 0.2 MPa of ethylene was continuously introduced at 25 ° C. After 30 minutes, the supply of ethylene was stopped, unreacted ethylene was removed, the ethylene in the autoclave was purged with nitrogen, and a very small amount of ethanol was added. The autoclave was opened, the contents were transferred to a 200 ml eggplant flask, and the solvent was distilled off under reduced pressure to obtain a semi-solid oligomer. The catalyst efficiency was 7946 kg Olig / Fe mol. Moreover, Mn of the obtained oligomer was 410, Mw was 740, and Mw / Mn was 1.9.

[Comparative Reference Example]
A semi-solid oligomer was obtained by performing the same operation as in Reference Example except that 1-decene (5 ml) was further added to the solution (E). The catalyst efficiency was 5186 kg Olig / Fe mol. Further, Mn of the obtained oligomer was 260, Mw was 550, and Mw / Mn was 2.1. Further, when the obtained oligomer was analyzed using ¹³ C NMR, it was found that 1-decene was not copolymerized and the product was an ethylene homo-oligomer.

The results show that the presence of an olefin such as 1-decene in the oligomerization reaction system reduces the catalytic efficiency of the ethylene polymerization catalyst. The fraction other than the lubricating oil fraction obtained in the first distillation step, and the fraction other than the lubricating oil base oil obtained in the second distillation step, use unreacted ethylene again as a raw material in the polymerization step For this purpose, when used as a part of feedstock oil, it was shown that it is important to return to the cracking and refining step from the viewpoint of maintaining the catalytic efficiency of the ethylene polymerization catalyst.

DESCRIPTION OF SYMBOLS 10 ... Pyrolysis refinement apparatus, 20 ... 1st reactor, 30 ... 1st distillation column, 40 ... 2nd reactor, 50 ... 2nd distillation column, 100 ... Lubricating base oil manufacturing apparatus, L1, L2, L3, L4, L4 ′, L5, L6, L6 ′...

Claims

A cracking and refining step of pyrolyzing the feedstock oil and refining the obtained pyrolysate to obtain ethylene;
A polymerization step of oligomerizing the ethylene in the presence of an ethylene polymerization catalyst to obtain a polymerization mixture containing an ethylene oligomer,
A first distillation step of distilling the polymerization mixture into a lubricating oil fraction and a fraction other than the lubricating oil fraction by distillation, respectively.
An isomerization step of hydroisomerizing the lubricating oil fraction in the presence of a hydroisomerization catalyst to obtain a reaction mixture containing the isomerized oil;
A second distillation step of fractionating the reaction mixture into a lubricating base oil and a fraction other than the lubricating base oil by distillation, respectively.
A fraction other than the lubricating oil fraction obtained in the first distillation step and / or a fraction other than the lubricating oil base oil obtained in the second distillation step, as a part of the base oil A method for producing a lubricating base oil, which is returned to the cracking and refining step.
The method for producing a lubricating base oil according to claim 1, wherein a fraction other than the lubricating base oil obtained in the second distillation step is returned to the cracking and refining step as a part of the base oil.
The method for producing a lubricating base oil according to claim 1 or 2, wherein the fraction other than the lubricating base oil is a lighter fraction lighter than the lubricating base oil.