JPWO2020059869A1 - Lubricating oil base oil manufacturing method - Google Patents

Abstract

A decomposition and purification step of thermally decomposing the raw material oil and purifying the obtained thermal decomposition product to obtain ethylene, and a polymerization step of oligomerizing ethylene in the presence of an ethylene polymerization catalyst to obtain a polymerization mixture containing an ethylene oligomer. The first distillation step in which the polymerization mixture is distilled into the lubricating oil distillate and the distillates other than the lubricating oil distillate, respectively, and the lubricating oil distillate is hydroisomerized and isomerized in the presence of a hydrogenation isomerization catalyst. The first distillation comprises an isomerization step of obtaining a reaction mixture containing a chemical oil and a second distillation step of distilling the reaction mixture into a lubricating oil base oil and a distillate other than the lubricating oil base oil, respectively. A lubricating oil group that returns the fraction other than the lubricating oil distillate obtained in the step and / or the distillate other than the lubricating oil base oil obtained in the second distillation step to the decomposition refining step as a part of the raw material oil. How to make oil.

Description

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

In the production of ethylene oligomers used as a raw material for lubricating oil base oils, the development of methods for obtaining high-purity ethylene oligomers containing no impurities is underway. For example, in Patent Document 1, an ethylene polymerization reaction is carried out 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 circulated in the polymerization reaction. A method for producing an ethylene oligomer to be used is described, and in the production method, it is described that the concentration of an olefin having 3 or more carbon atoms in an organic solvent circulating in a polymerization reaction system is 2% by weight or less. ..

JP-A-2002-255864

By the way, in the production of a lubricating oil base oil, in order to obtain a lubricating oil 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. be. Therefore, for the purpose of improving the yield of the target lubricating oil base oil, it is desirable to maintain the reaction efficiency of the catalyst used in each step as much as possible, including the ethylene polymerization reaction catalyst.

In this respect, 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 the method described in Patent Document 1 for recycling, an ethylene oligomer having a certain degree of high purity can be surely obtained. However, the organic solvent also contains by-products (impurities) such as olefins, and when these impurities are supplied to the polymerization reaction system, the catalytic efficiency of the ethylene polymerization catalyst is lowered, and the target lubricating oil is used. It may cause a decrease in the yield of base oil.

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

In order to solve the above problems, the present inventor paid attention to a fraction other than the lubricating oil base oil obtained by the distillation process, which had no utility value other than burning as a fuel in the conventional production of the lubricating oil base oil. bottom. Then, in the step of producing the lubricating oil base oil from the ethylene oligomer, by reusing the distillate corresponding to the above as a part of the raw material oil in the thermal decomposition step, high-purity ethylene can be regenerated and used in the polymerization step. By utilizing it, it has been found that the mixing of impurities such as olefins, which causes a decrease in the efficiency of the polymerization catalyst, can be suppressed, and the lubricating oil base oil can be produced in a high yield, and the present invention has been completed.

The method for producing a lubricating oil base oil according to the present invention includes a decomposition and purification step of thermally decomposing the raw material oil and refining the obtained thermal decomposition product to obtain ethylene, and oligomerizing ethylene in the presence of an ethylene polymerization catalyst. A polymerization step of obtaining a polymerization mixture containing an ethylene oligomer, a first distillation step of distilling the polymerization mixture into a lubricating oil distillate and a distillate other than the lubricating oil distillate, and hydrogenating the lubricating oil distillate. The isomerization step of hydrogenating and isomerizing in the presence of an isomerization catalyst to obtain a reaction mixture containing an isomerized oil, and the first step of distilling the reaction mixture into distillates other than the lubricating oil base oil and the lubricating oil base oil by distillation. A distillate other than the lubricating oil distillate obtained in the first distillation step and / or a distillate other than the lubricating oil base oil obtained in the second distillation step is used as a raw material oil. It is characterized by returning to the decomposition and purification process as a part of.

In particular, it is preferable that the fraction other than the lubricating oil base oil obtained in the second distillation step is returned to the decomposition refining step as a part of the raw material oil.

Fractions other than the lubricating oil base oil may be lighter fractions than the lubricating oil base oil.

According to the present invention, there is provided a new method for producing a lubricating oil base oil, which can efficiently produce a lubricating oil base oil.

It is the result (chromatogram) of the electrolytic desorption mass spectrometry (FD-MS) of the isomerized oil obtained in Example 1. It is a flow chart which shows an example of the lubricating oil base oil manufacturing apparatus for carrying out the manufacturing method of the lubricating oil base oil which concerns on one Embodiment of this 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 oil base oil according to the present embodiment includes a decomposition and purification step of thermally decomposing the raw material oil and purifying the obtained thermal decomposition product to obtain ethylene, and an oligomer of ethylene in the presence of an ethylene polymerization catalyst. A polymerization step of converting to obtain a polymerization mixture containing an ethylene oligomer, a first distillation step of distilling the polymerization mixture into a lubricating oil distillate and a distillate other than the lubricating oil distillate, and hydrogen for the lubricating oil distillate. An isomerization step of hydrogenating isomerization in the presence of a isomerization catalyst to obtain a reaction mixture containing an isomerized oil, and fractional distillation of the reaction mixture into distillates other than the lubricating oil base oil and the lubricating oil base oil, respectively. It comprises 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 is used as a raw material oil. It is supplied to the above decomposition and purification step as a part.

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

First, the decrease in catalytic efficiency of the ethylene polymerization catalyst is due to the fact that by-products (impurities) such as olefins other than ethylene are also supplied to the polymerization reaction system when unreacted ethylene is supplied to the polymerization reaction system again. it is conceivable that. On the other hand, in the method for producing a lubricating oil base oil according to the present embodiment, a distillate other than the lubricating oil distillate obtained in the first distillation step and / or a lubricating oil group obtained in the second distillation step. The distillate other than the oil is returned to the decomposition and purification step as a part of the raw material oil, and the high-purity ethylene obtained in the decomposition and purification step is brought into contact with the ethylene polymerization catalyst in the polymerization step to bring the catalytic activity of the ethylene polymerization catalyst into contact. It is considered that the mixing of impurities that hinders the above-mentioned is suppressed, and as a result, the decrease in the catalytic efficiency of the ethylene polymerization catalyst can be suppressed.

Further, in the method for producing a lubricating oil base oil according to the present embodiment, fractions other than the lubricating oil fraction obtained in the first distillation step and / or other than the lubricating oil base oil obtained in the second distillation step. By returning the distillate to the decomposition and purification process as a part of the raw material oil and subjecting it to the decomposition and purification process again, ethylene can be regenerated and basic chemistry such as propylene, butadiene, isoprene, cyclopentadiene, benzene, toluene and xylene. It is also possible to produce goods together.

Further, in the method for producing a lubricating oil base oil according to the present embodiment, since high-purity ethylene regenerated by returning the distillate to the decomposition refining step as a part of the raw material oil is used as a raw material, conventional slack wax or To improve the yield of lubricating oil base oil in all processes as compared with the lubricating oil base oil manufacturing method in which raw material oil such as atmospheric residual oil hydrocracked oil is subjected to hydrocracking and hydroisomerization steps. In addition to being possible, it is also possible to suppress the traction coefficient of the obtained lubricating oil base oil. The present inventors presume that the reason why such an effect is obtained is the peculiarity of the carbon number distribution of the lubricating oil base oil obtained by the method for producing the lubricating oil base oil according to the present embodiment.

That is, first, in the case of the conventional wax isomerized oil, the raw material wax such as wax obtained by FT synthesis is usually a hydrocarbon compound having an even number of carbon atoms (hydrocarbon compound having 2 n carbon atoms; n is 1 or more). (The same applies hereinafter) and a hydrocarbon compound having an odd number of carbon atoms (hydrocarbon compound having 2n + 1 carbon atoms), and the ratios of the two are almost the same. On the other hand, the ethylene oligomer obtained by the production method according to the present embodiment may undergo thermal decomposition due to isomerization (for example, formation of paraffin having 2n-1 carbon atoms due to isomerization of paraffin having 2n carbon atoms). However, most of them are hydrocarbon compounds having an even number of carbon atoms (hydrocarbon compounds having an even number of carbon atoms), and the proportion of hydrocarbon compounds having an even number of carbon atoms is large, showing a peculiar carbon number distribution. ..

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

Hereinafter, each step will be described in detail.
(Decomposition and purification process)
In the decomposition refining step, the raw material oil is thermally decomposed and the obtained thermal decomposition product is refined to obtain ethylene. Specifically, a method of introducing the raw material oil into a thermal decomposition refining apparatus such as a naphtha cracker can be mentioned. The raw material oil to be subjected to thermal decomposition 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, which will be described later. include. These fractions will be described in detail in the first distillation step and the second distillation step described later.

In the decomposition and refining step, after the raw material oil is thermally decomposed, the obtained thermally decomposed product (decomposed oil) may be subjected to the refining step to obtain higher purity ethylene, but it is an existing thermal decomposition and refining apparatus. When a naphtha cracker or the like is used, the purification step of the naphtha cracker can be used as it is. By including the purification step, not only higher purity ethylene can be obtained, but also basic chemicals such as propylene, butadiene, isoprene, cyclopentadiene, benzene, toluene and xylene can be obtained 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, still more preferably 99.9% or more.

The content of the distillate other than the lubricating oil fraction obtained in the first distillation step and / or the distillate other than the lubricating oil base oil obtained in the second distillation step contained in the raw material oil 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 distillate contained in the raw material oil is also not particularly limited, and is usually less than 100% by mass, preferably 90% by mass or less, and more preferably 80% by mass or less. From the viewpoint of stable operation of the pyrolysis refining apparatus, it is preferable to use a raw material oil in which the content of the distillate is kept constant.

As the raw material oil other than the above fraction, the raw material oil (naphtha) which is usually subjected to thermal decomposition can be used without particular limitation. In addition to naphtha, ethane, LPG, kerosene, light oil and the like can also be used.

The method for thermally decomposing the raw material oil to obtain the decomposed oil containing ethylene can be appropriately set according to the composition of the raw material oil to be subjected to the thermal decomposition and the performance of the target lubricating oil base oil. For example, the thermal decomposition temperature is preferably 700 to 1000 ° C., and the residence time is preferably 0.001 to 10 seconds. After thermal decomposition, the product is rapidly cooled and distilled to distill it, in addition to ethylene, C3 component containing methane and propylene, C4 component containing butadiene, C5 component containing isoprene and cyclopentadiene, and components such as benzene, toluene and xylene. It is possible to separate into.

(Polymerization process)
In the polymerization step, the ethylene obtained in the above 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, a method of introducing ethylene into a polymerization reaction apparatus filled with an ethylene polymerization catalyst can be mentioned. The method for introducing ethylene into the polymerization reactor is not particularly limited. An α-olefin such as propylene or 1-butene may be copolymerized as long as the effect of the present invention is not significantly impaired.

In addition, a solvent is usually used in the polymerization reaction. Examples of the solvent include aliphatic hydrocarbon solvents such as butane, pentane, hexane, heptane, octane, cyclohexane, methylcyclohexane and decalin; aromatic hydrocarbon solvents such as tetralin, benzene, toluene and xylene. An ethylene polymerization catalyst can be dissolved in these solvents to carry out solution polymerization, slurry polymerization and the like. Since ethylene oligomers have an even number of carbons, it is preferable to use a solvent having an odd number of carbons in order to facilitate separation from them. Pentane, heptane, methylcyclohexane, toluene, etc. match the properties.

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

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).

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'indicates a free radical having an oxygen atom and / or a nitrogen atom, and a plurality of R'in the same molecule may be the same or different. Y represents a chlorine atom or a bromine atom.

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 a linear alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group and an n-hexyl group; iso. -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 can be mentioned.

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

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

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

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

In the iron complex represented by the general formula (1), the compound constituting the ligand (hereinafter, also referred to as a diimine compound) dehydrates and condenses, for example, dibenzoylpyridine and aniline compound in the presence of an acid. It can be synthesized by.

A preferred embodiment of the method for producing a diimine compound is a first step of dissolving 2,6-dibenzoylpyridine, an aniline compound, and an acid in a solvent and dehydrating and condensing them under solvent heating and reflux, and a reaction mixture after the first step. A second step of obtaining a diimine compound by separating and purifying the compound is provided.

As the acid used in the first step, for example, an organoaluminum compound can be used. Organic aluminum compounds include trimethylaluminum, triethylaluminum, tripropylaluminum, triisopropylaluminum, tributylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, diethylaluminum chloride, ethylaluminum dichloride, ethylaluminum sesquichloride, methylaluminoxane. And so on.

As the acid used in the first step, a protonic acid may be used in addition to the above-mentioned organoaluminum compound. Protonic acid is used as an acid catalyst to 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, paratoluenesulfonic acid and the like. When these protonic acids are used, it is preferable to remove water by-produced with a Dean-Stark water separator or the like. It is also possible to carry out the reaction 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.

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

The reaction conditions in the first step can be appropriately selected depending on the type and amount of the raw material compound, the acid and the solvent.

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 to decompose and remove aluminum, and then purify the compound.

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

Further, the method for extracting the complex from the mixture of the diimine compound and iron is not particularly limited, and for example,
(A) When a solvent is used in the mixture, the solvent is distilled off and the solid matter is filtered off.
(B) A method for filtering out the precipitate formed from the mixture,
(C) A method of adding a poor solvent to the mixture to purify the precipitate and filter it.
(D) A method for taking out the solvent-free mixture as it is,
And so on. After that, 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, tetrafdrofuran, benzene, toluene, xylene, cyclohexane, methylcyclohexane and the like. Examples of the solvent capable of dissolving the iron salt include alcohol-based solvents such as methanol, ethanol and isopropanol, and tetrahydrofuran and the like.

Examples of iron salts include iron (II) chloride, iron (III) chloride, iron (II) bromide, iron (III) bromide, iron (II) acetylacetonate, and iron (III) acetylacetonate. Examples thereof include iron (II) acetate and iron (III) acetate. Those salts having a ligand such as a solvent or water may be used. Among these, the salt of iron (II) is preferable, and iron (II) chloride is more preferable.

The solvent for bringing the diimine compound into contact with iron is not particularly limited, and either a non-polar solvent or a polar solvent can be used. Examples of the non-polar solvent include hydrocarbon solvents such as hexane, heptane, octane, benzene, toluene, xylene, cyclohexane and methylcyclohexane. Examples of the polar solvent include polar protic solvents such as alcohol solvents and polar aprotic solvents such as tetrahydrofuran. Examples of the alcohol solvent include methanol, ethanol, isopropyl alcohol and the like. In particular, when the mixture is used as it is as a catalyst, it is preferable to use a hydrocarbon solvent that has substantially no effect on olefin polymerization.

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

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

The ethylene polymerization catalyst containing the iron complex represented by the general formula (1) may further contain an organoaluminum compound in order to allow the polymerization reaction to proceed more efficiently. Examples of the organoaluminum compound include trialkylaluminum and methylaluminoxane. 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 trialkylaluminum include trimethylaluminum, triethylaluminum, triisobutylaluminum, tributylaluminum, trihexylaluminum, and trioctylaluminum. From the viewpoint of more effectively improving the catalytic 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 a molar ratio when the number of moles of the iron complex is G and the number of moles of aluminum atoms of the organoaluminum compound is H. 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 an increase in cost while exhibiting more sufficient polymerization activity.

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

As the organoaluminum compound, when used in combination trimethylaluminum and methylaluminoxane, the content of trimethylaluminum and methylaluminoxane in the ethylene polymerization catalyst, H ₁ moles of _{trimethylaluminum,} the number of moles of the aluminum atoms in the methylaluminoxane In _{the case of H 2} , 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 factors of cost increase while exhibiting more sufficient catalytic efficiency.

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

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

Examples of the boron compound include arylboron compounds such as trispentafluorophenylboran. Further, as the boron compound, a boron compound having an anionic species can be used. For example, aryl borates such as tetrakispentafluorophenyl borate and tetrakis (3,5-trifluoromethylphenyl) borate can be mentioned. Specific examples of arylborates include lithium tetrakispentafluorophenylborate, sodium tetrakispentafluorophenylborate, N, N-dimethylanilinium tetrakispentafluorophenylborate, trityltetrakispentafluorophenylborate, and lithium tetrakis (3,5-tri). Fluoromethylphenyl) borate, sodium tetrakis (3,5-trifluoromethylphenyl) borate, N, N-dimethylanilinium tetrakis (3,5-trifluoromethylphenyl) borate, trityltetrakis (3,5-trifluoromethyl) Phenyl) Borate and the like can be mentioned. Among these, N, N-dimethylanilinium tetrakispentafluorophenylborate, trityltetrakispentafluorophenylborate, N, N-dimethylanilinium tetrakis (3,5-trifluoromethylphenyl) borate or trityltetrakis (3,5) -Trifluoromethylphenyl) borate is preferred. These boron compounds may be used alone or in combination of two or more.

When the organoaluminum compound and the boron compound are used in combination in the ethylene polymerization catalyst, the content ratio of the organoaluminum compound and the boron compound is the molar ratio when the number of moles of the organoaluminum compound is H and the number of moles of the boron compound is J. The ratio is preferably H: J = 1000: 1 to 1: 1, more preferably 800: 1 to 2: 1, and even more preferably 600: 1 to 10: 1. Within the above range, it is possible to suppress an increase in cost while exhibiting more sufficient catalytic 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 ensuring more sufficient catalyst efficiency by suppressing the deactivation of the iron complex. Compound (hereinafter, also referred to as a ligand) may be contained.

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, and R ″ may be the same or different. '''Indicates a free radical having 0 to 6 carbon atoms having an oxygen atom and / or a nitrogen atom, and a plurality of R'''in the same molecule may be the same or different.

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 a linear alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group and an n-hexyl group; iso. -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 can be mentioned.

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

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

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.

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

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 of the general formula (1), R ″ of the general formula (2), and the general formula ( The R'of 1) and the R'''of the general formula (2) may be the same or different, but from the viewpoint of maintaining the same performance as the iron complex represented by the general formula (1). It is preferable that they are the same.

When the ethylene polymerization catalyst according to the present embodiment contains the above-mentioned ligand, the content ratio of the iron complex and the ligand is not particularly limited. The ligand / iron complex ratio is preferably 1/100 to 100/1, more preferably 1/50 to 50/1, still more preferably 1/10 to 10/1, and particularly preferably 1/5 in molar ratio. ~ 5/1, very preferably 1/3 to 3/1. When the ligand / iron complex ratio is 1/100 or more, the catalytic efficiency can be increased by suppressing the deactivation of the iron complex, and when it is 100/1 or less, the effect of adding the ligand is exhibited. The cost can be suppressed.

The method for producing the above-mentioned ethylene polymerization catalyst is not particularly limited. For example, when the above-mentioned ethylene polymerization catalyst contains an iron complex represented by the above-mentioned general formula (1) and an 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, and a method of adding and mixing a solution containing an iron complex represented by the general formula (1) to a solution containing an organoaluminum compound. The method of doing this can be mentioned. Further, for example, when the above-mentioned boron compound and ligand are further contained in addition to the iron complex and the organoaluminum compound represented by the general formula (1), all these components may be brought into contact with each other at once. However, they may be contacted in any order. As a method for producing an ethylene polymerization catalyst according to the present embodiment, for example,
(A) A method in which a solution containing an iron complex represented by the general formula (1) and a solution containing a boron compound are mixed and then brought into contact with an organic aluminum compound (B) An iron complex represented by the general formula (1). Method of contacting a boron compound after mixing the solution containing the above and the solution containing the organic aluminum compound (C) After mixing the solution containing the boron compound and the solution containing the organic aluminum compound, it is represented by the general formula (1). Method of contacting the iron complex to be formed (D) Method of contacting the organic aluminum compound after mixing the solution containing the iron complex represented by the general formula (1) and the solution containing the ligand (E) General formula (1) ) Is mixed with the solution containing the organic aluminum compound, and then the ligand is brought into contact with the solution. (F) The solution containing the organic aluminum compound and the solution containing the ligand are mixed, and then the general formula is used. Method for contacting iron complex represented by (1) (G) After mixing a solution containing an iron complex represented by the general formula (1) and a solution containing a boron compound, a solution containing an organic aluminum compound is added. , Mixing, and then contacting the ligand (H) After mixing the solution containing the iron complex represented by the general formula (1) and the solution containing the boron compound, the solution containing the ligand is added and mixed, and then Method for contacting organic aluminum compounds (I) After mixing a solution containing an iron complex represented by the general formula (1) and a solution containing an organic aluminum compound, a solution containing a boron compound is added and mixed, and then a ligand is used. (J) After mixing the solution containing the iron complex represented by the general formula (1) and the solution containing the organic aluminum compound, the solution containing the ligand is added and mixed, and then the boron compound is contacted. Method (K) A method (L) in which a solution containing an iron complex represented by the general formula (1) and a solution containing a ligand are mixed, then a solution containing an organic aluminum compound is added and mixed, and then a boron compound is brought into contact with the solution (L). ) A method in which a solution containing an iron complex represented by the general formula (1) and a solution containing a ligand are mixed, then a solution containing a boron compound is added and mixed, and then an organic aluminum compound is brought into contact with the (M) boron compound. A method of mixing a solution containing an organic aluminum compound and a solution containing an organic aluminum compound, then adding and mixing a solution containing an iron complex represented by the general formula (1), and then contacting a ligand (N) A solution containing a boron compound. After mixing the solution containing the organic aluminum compound, the solution containing the ligand is added and mixed, and then the iron complex represented by the general formula (1) is added. (O) After mixing the solution containing the boron compound and the solution containing the ligand, the solution containing the iron complex represented by the general formula (1) is added and mixed, and then the organoaluminum compound is contacted. Method (P) After mixing the solution containing the boron compound and the solution containing the ligand, the solution containing the organoaluminum compound is added and mixed, and then the iron complex represented by the general formula (1) is brought into contact with the method (Q). ) A method of mixing a solution containing an organoaluminum compound and a solution containing a ligand, then adding and mixing a solution containing an iron complex represented by the general formula (1), and then contacting the boron compound (R) Organoaluminium. A method of mixing a solution containing a compound and a solution containing a ligand, then adding and mixing a solution containing a boron compound, and then contacting an iron complex represented by the general formula (1) (S) General formula (1). A method in which a boron compound is brought into contact with a solution containing an iron complex represented by (T) and then a solution containing an organoaluminum compound is added and mixed (T) The boron compound is added to a solution containing an iron complex represented by the general formula (1). Then, a solution containing trimethylaluminum is added and mixed, and methylaluminoxane is brought into contact with the mixture.

The ethylene oligomer means an ethylene homopolymer having a number average molecular weight (Mn) of 10,000 or less, or a copolymer of ethylene and an α-olefin. The Mn of the ethylene oligomer obtained in the polymerization step can be appropriately adjusted according to the intended use, but when the ethylene oligomer is used as a raw material for a lubricating oil or the like, the Mn is preferably 200 to 5000, more preferably 300 to 4000. , 350-3000 is more preferable. The degree of dispersion is the ratio of the weight average molecular weight (Mw) to Mn and is expressed as Mw / Mn. For example, it is preferably 1.0 to 5.0, more preferably 1.1 to 3. It is 0. The ethylene oligomers Mn and Mw can be determined as polystyrene-equivalent quantities based on a calibration curve prepared from standard polystyrene, for example, 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 for example, based on the total amount of ethylene oligomer, it is preferably 40% by mass or more, more preferably 50% by mass or more, still more preferably 60% by mass or more. Is. The upper limit of the content of the linear hydrocarbon compound is also not particularly limited, and is usually 100% by mass or less, preferably 90% by mass or less, and more preferably 85% by mass or less.

In the composition 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 isomerized oil, it is more preferable that the hydrocarbon compound having an odd number of carbon atoms is not substantially contained.

The content of the linear hydrocarbon compound means a value obtained by performing 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 values corresponding to normal paraffin with respect to the total peak area value of the chromatogram. Obtained as a percentage. Here, in the case of a hydrocarbon compound having the same carbon number, the hydrocarbon compound having the highest boiling point (longest distillation time) is normal paraffin, so the above standard sample was measured when calculating the carbon number. There are n peaks existing 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. It shall correspond to non-normal paraffin having the same carbon number as, and shall distinguish between normal paraffin and non-normal paraffin having the same carbon number.
(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 amount: 0.5 μL (injection amount of sample diluted 20 times with carbon disulfide)
Detector: Hydrogen flame ionization detector (FID)

The content of the above-mentioned hydrocarbon compound having an even number of carbon atoms is determined by analyzing the ethylene oligomer contained in the polymerization mixture by the electrolytic desorption mass analysis method under the following conditions, and from the mass number of the obtained chromatogram, ethylene. It means a value obtained by calculating the ratio of hydrocarbon compounds having an even number of carbon atoms in the total amount of oligomers.
(Electrolytic desorption mass spectrometry conditions)
Equipment: JEOL JMS-T300GC
Ionization method: FD (Field Desorption)
Ion source temperature: Room temperature Counter electrode voltage: -10 kV
Emitter current: 6.4mA / 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 later, but the ethylene oligomer may be taken out from the obtained polymerization mixture and subjected to the first distillation step, or the polymerization may be carried out. The mixture may be concentrated and subjected to the first distillation step as a concentrate having an increased concentration of ethylene oligomers. It is preferable to concentrate the polymerization mixture so that a solvent or the like that is not a raw material for the lubricating oil base oil is not sent to the isomerization step described later. Examples of the method for concentrating the polymerization mixture include a method for concentrating the polymerization mixture in a concentrator such as a flash tank.

The volatile component obtained by concentrating the polymerization mixture with a concentrator or the like usually contains unreacted ethylene, a polymerization solvent, and other light oligomers. The solvent is preferably recovered by distillation or the like and reused, and 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. In that case, impurities such as butene that can be generated by the polymerization reaction are mixed and accumulated in the system, so when recovering ethylene, a part of it should be discharged to the outside of the system to keep the amount of impurities constant. , Leads to stable polymerization. Ethylene containing impurities discharged from the system can be returned to the decomposition and purification process.

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

Examples of the boiling point range of the lubricating oil fraction obtained by the first distillation step include fractions having a boiling point range of 250 to 500 ° C. Further, in the case of efficiently obtaining the isomerized oil corresponding to 70 Pale, SAE10, VG6, etc. obtained in each step described later, the boiling point range of the lubricating oil fraction obtained in each of the first distillation steps is set as follows. can do.
Isolation oil corresponding to 70 Pale: Fraction in boiling point range 300 to 460 ° C. Fraction oil corresponding to SAE10: Distillate in boiling point range 360 to 500 ° C. Fraction VG6 in boiling point range 250 to 440 ° C. Minutes For example, a boiling point range of 250 to 500 ° C. indicates that the initial distillate point and the end point are within the range of 250 to 500 ° C.

The distillation conditions in the first distillation step are not particularly limited as long as the desired 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 fractional distillation by vacuum distillation, or may be a step of fractional distillation by combining atmospheric distillation (or distillation under pressure) and vacuum distillation. Further, for example, it may be fractionated as a single fraction or as a plurality of fractions according to the viscosity grade.

Examples of the fraction other than the lubricating oil fraction include a solvent, a fraction containing unreacted ethylene, and the like. Fractions other than the lubricating oil fraction may be purified if desired and reused in the polymerization step, or may be returned to the decomposition 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 process)
In the isomerization step, the lubricating oil fraction is hydrogenated and isomerized in the presence of a hydrogenation isomerization catalyst to obtain a reaction mixture containing the isomerized oil. More specifically, the isomerization step is a step of hydrogenating an ethylene oligomer by bringing an ethylene oligomer into contact with a hydrogenation isomerization catalyst in the presence of hydrogen (molecular hydrogen). The hydrogenation isomerization here includes, in addition to the isomerization of normal paraffin to isoparaffin, the conversion of olefins to paraffin by hydrogenation and the like.

The hydrogenation isomerization catalyst may contain either crystalline or amorphous material. Examples of the crystalline material include a molecular sieve containing aluminosilicate (zeolite) or silicoaluminophosphate (SAPO) as a main component and having a 10- or 12-membered ring passage. Specific examples of zeolite include ZSM-22, ZSM-23, ZSM-35, ZSM-48, ZSM-57, ferrierite, ITQ-13, MCM-68, MCM-71 and the like. Further, as an example of aluminophosphate, ECR-42 can be mentioned. Examples of molecular sieves include zeolite beta and MCM-68. Among these, 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 hydrogen form. The reduction of the hydrogenation isomerization catalyst can occur in situ during the hydrogenation isomerization, but a hydrogenation isomerization catalyst that has been subjected to a reduction treatment in advance may be subjected to the hydrogenation isomerization.

Examples of the amorphous material of the hydrogenation isomerization catalyst include alumina doped with a Group 3 metal, fluoride alumina, silica-alumina, and fluoride silica-alumina.

Preferred embodiments of the hydrogenation isomerization catalyst include bifunctionality, i.e., a metal hydrogenated component that is at least one Group 6 metal, at least one Group 8-10 metal, or a mixture thereof. Be done. Preferred metals are Group 9-10 noble metals such as Pt, Pd or mixtures thereof. The amount of these metals attached is preferably 0.1 to 30% by mass based on the total amount of the catalyst. Examples of the catalyst preparation and metal mounting method include an ion exchange method and an impregnation method using a degradable metal salt.

When a molecular sieve is used, it may be composited with a binder material having heat resistance under hydrogenation isomerization conditions, or may be 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, tria, and zirconia, silica-alumina-tria, silica-alumina-magnesia, and the like. Examples thereof include inorganic oxides such as a combination of acid components of oxides such as. The amount of molecular sieve in the hydrogenation isomerization catalyst is preferably 10 to 100% by mass, more preferably 35 to 100% by mass, based on the total amount of the catalyst. The hydrogenation isomerization catalyst is formed by a method such as spray drying or extrusion. The hydrogenation isomerization catalyst can be used in a sulfided or non-sulfided embodiment, and the sulfided embodiment is preferable.

Regarding the hydrogenation isomerization 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 (1480 kPa to 17339 kPa). a 200psig~2500psig), liquid hourly space velocity is preferably ^{0.1hr -1 ~10hr} -1, more preferably from ^{0.1hr -1 ~5hr} -1, a hydrogen / oil ratio is preferably ^{45 m} 3 / ^{m 3 ~1780m 3 / m 3 (250scf /} B~10000scf / B), more preferably from ^{89m 3 / m 3 ~890m 3 /} m 3 (500scf / B~5000scf / B). The above conditions are an example, and the hydrogenation isomerization conditions are preferably selected as appropriate according to differences in raw materials, catalysts, devices, 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 into fractions other than the lubricating oil base oil and the lubricating oil base oil by distillation. Fractions other than the lubricating oil base oil are usually light fractions that are lighter than the lubricating oil base oil and heavy fractions that are heavier than the lubricating oil base oil. Such fractions are, for example, atmospheric distillation (or distillation under pressure) in which a light fraction is fractionated from a reaction mixture containing an isomerized oil, and a desired lubricating oil group from the bottom oil of the atmospheric distillation. It is carried out by vacuum distillation, which fractionates the oil fraction.

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

In the fractional distillation of the lubricating oil base oil, a plurality of lubricating oil base oil fractions can be obtained according to the purpose by setting a plurality of cut points and distilling under reduced pressure. For example, in order to obtain a lubricating oil base oil corresponding to 70 Pale, which is suitable as a lubricating oil base oil for ATF and shock absorbers, the boiling point range at normal pressure is set to a ^{kinematic viscosity of 2.7 mm 2 / s at 100 ° C.} Method of recovering the distillate from 330 ° C to 410 ° C; kinematic viscosity at 100 ° C to obtain a lubricating oil base oil corresponding to SAE-10 suitable as a lubricating oil base oil for engine oils satisfying the specifications of API Group III. A method of recovering a distillate having a boiling point range of 410 ° C to 460 ° C at normal pressure with a target value of 4.0 mm ^{2 / s; corresponding to SAE-20 suitable as a lubricating oil base oil for various gear oils and hydraulic oils.} Lubricating oil A method of recovering a distillate having a boiling point range of 460 ° C to 500 ° C at normal pressure with a ^{kinematic viscosity of 5.6 mm 2} / s at 100 ° C as a target value in order to obtain a base oil; lubrication equivalent to VG6. In order to obtain the oil base oil, a method of recovering a distillate having a boiling point range of 330 ° C. or lower with a ^{kinematic viscosity of 2.0 mm 2 / s at 100 ° C. as a target value can be mentioned.} The SAE viscosity means a standard defined by the Society of Automotive Engineers.

The viscosity grade of the lubricating oil base oil obtained through the second distillation step is not particularly limited, but its 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 a plurality of cut points are set in the second distillation step to obtain a plurality of lubricating oil base oil distillates according to the purpose, the kinematic viscosity of the obtained lubricating oil base oil at 100 ° C. is determined. It is preferably as follows.
(I) less than the kinematic viscosity at 100 ° C. is 1.5 mm ² / s or more 2.3 mm ² / s, more preferably kinematic viscosity at 1.8mm~2.1mm ² / s lubricating base oils (II) 100 ° C. There 2.3 mm ² / s or more 3.0mm less than ² / s, more preferably a kinematic viscosity at 2.4~2.8mm ² / s lubricating base oil (III) 100 ℃ 3.0~20mm ² / Lubricating oil base oil of s, more preferably 3.2 to 11 mm ² / s, further preferably 3.5 to 5.0 mm ² / s, particularly preferably 3.6 to 4.0 mm ^{2 / s.}

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

The density of the lubricating oil base oil at 15 ° C. (ρ ₁₅ , unit: g / cm ³ ) 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 It is 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, a lubricating oil base oil having excellent viscosity-temperature characteristics, thermal / oxidation stability, volatilization prevention properties, and low-temperature viscosity characteristics can be obtained, and a lubricating oil base oil can be obtained. When an additive is blended in, the effectiveness of the additive can be sufficiently ensured.

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

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

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

When gas chromatography analysis is performed on the lubricating oil base oil, the average carbon number of the hydrocarbon compound contained in the lubricating oil base oil can be appropriately selected according to the viscosity grade. For example, the average carbon number of the lubricating oil base oil (I) is preferably 15 to 25, more preferably 18 to 22. The average carbon number of the lubricating oil base oil (II) is preferably 15 to 30, more preferably 20 to 25. The average carbon number of the lubricating oil 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 oil base oil having excellent energy saving properties can be obtained.

Since the lubricating oil base oil obtained by the method for producing a lubricating oil 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 content balance of the hydrocarbon compounds is not uniform. In the composition of the hydrocarbon compound contained in the lubricating oil 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 oil base oil, for example. It is preferably 60% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more, and particularly preferably 85% by mass or more.

The above-mentioned carbon number distribution and average carbon number are values obtained by mass spectrometry of the isomerized oil. FIG. 1 is an FD-MS chromatogram of the isomerized oil obtained in Example 1. For example _{, the peak near MS338 (C 24} H ₅₀ ) is C24, and the peak near _{MS 310 (C 22} H ₄₆ ) is C22. And. The peak near MS324 (C ₂₃ H ₄₈ ) is C23. The average carbon number is obtained by adding up these adjacent ionic strengths to obtain the content of each carbon number and dividing them by the total amount. In addition, the carbon number distribution is obtained from the beginning and end of the chromatogram.

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

The lubricating oil base oil obtained above can be preferably used as a lubricating oil base oil for various purposes. Lubricating oils Specific examples of base oils are lubricating oils used in internal combustion engines such as gasoline engines for passenger cars, gasoline engines for two-wheeled vehicles, diesel engines, gas engines, gas heat pump engines, marine engines, and power generation engines. (Lubricating oil for internal combustion engine), Lubricating oil used for drive transmission devices such as automatic transmissions, manual transmissions, stepless transmissions, and final speed reducers (oil for drive transmission devices), flood control 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, papermaking machine oil, machine tool oil, slip guide surface used for equipment Examples thereof include oil, electrically insulating oil, cutting oil, pressing oil, rolling oil, and heat treatment oil.

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

The other base oil used in combination with the lubricating oil base oil obtained by the production method according to the present embodiment is not particularly limited, but the mineral oil-based base oil is classified into, for example, Group I to Group III of the API classification. Mineral oil and the like to be used can be mentioned. In addition, each group of API classification means according to the classification of the lubricating oil grade of the American Petroleum Institute (API (American Petroleum Institute)).

The synthetic base oil includes poly-α-olefin or hydride thereof, isobutene oligomer or hydride thereof, isoparaffin, alkylbenzene, alkylnaphthalene, and diester (ditridecylglutarate, di-2-ethylhexyl adipate, diisodecyl adipate, ditri). Decyl adipate, di-2-ethylhexyl sebacate, etc.), polyol esters (trimethylolpropane caprilate, trimethylolpropane pelargonate, 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 α-olefin oligomer or co-oligomer having 2-32 carbon atoms, preferably 6 to 16 carbon atoms (1-octene oligomer, decene oligomer, ethylene-propylene co-oligomer, etc.) and them. Oligomers can be mentioned.

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

Further, if necessary, various additives can be added to the lubricating oil base oil obtained by the production method according to the present embodiment or the mixed base oil of the lubricating oil base oil and another base oil. The additive is not particularly limited, and any additive conventionally used in the field of lubricating oil can be blended. Specific examples of the lubricating oil additive include an antioxidant, an ashless dispersant, a metal-based cleaning agent, an extreme pressure agent, an anti-wear agent, a viscosity index improver, a flow point lowering agent, a friction modifier, and an oil-based agent. , Corrosion inhibitor, rust preventive, anti-emulsifying agent, metal inactivating agent, seal swelling agent, antifoaming agent, coloring agent and the like. These additives may be used alone or in combination of two or more.

Fractions other than the lubricating oil base oil obtained by the second distillation step include, for example, a fraction lighter than the lubricating oil base oil and a fraction heavier than the lubricating oil base oil. These fractions can also be returned to the decomposition refining process and used as raw material oil.

In the method for producing a lubricating oil base oil according to the present embodiment, fractions other than the lubricating oil fraction obtained in the first distillation step described above and / or the lubricating oil base oil obtained in the second distillation step It is characterized in that the fractions other than the above are returned to the decomposition refining step as a part of the raw material oil. Above all, the fraction returned to the decomposition refining step is preferably a fraction other than the lubricating oil base oil obtained in the second distillation step, and the fraction is a light fraction lighter than the lubricating oil base oil. Is more preferable.

Fractions other than the lubricating oil fraction obtained in the first distillation step and fractions other than the lubricating oil base oil obtained in the second distillation step separate a polymerization mixture containing an ethylene oligomer and a reaction mixture, respectively. It is obtained by distilling. The ethylene oligomer is a hydrocarbon compound in which most of the constituent hydrocarbon compounds have an even number of carbon atoms. Therefore, the fraction has an uneven content balance between the hydrocarbon compound having an even number of carbon atoms and the hydrocarbon compound having an odd number of carbon atoms. In the composition 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 on the basis of the total amount of the fraction, for example, 50 is preferable. It is less than mass%, more preferably 45% by mass or less, still more preferably 40% by mass or less.

Up to this point, a preferred embodiment of the method for producing a lubricating oil base oil according to the present invention has been described, but the present invention is not limited to the above embodiment, and various types generally adopted in the production of a lubricating oil base oil are used. The steps of the above may be appropriately provided.

Next, a lubricating oil base oil producing apparatus for carrying out the method for producing a lubricating oil base oil according to the present embodiment will be described. FIG. 2 is a flow chart showing an example of a lubricating oil base oil manufacturing apparatus for carrying out the method for producing a lubricating oil base oil according to an embodiment of the present invention.

The lubricating oil base oil production apparatus 100 shown in FIG. 2 has a thermal decomposition refining apparatus 10 that thermally decomposes the raw material oil introduced from the flow path L1 and purifies the obtained thermal decomposition product to obtain ethylene, and heat. A first reactor 20 for oligomerizing ethylene (decomposed oil containing ethylene) supplied from the decomposition purification apparatus 10 through the flow path L2, and an ethylene oligomer supplied from the first reactor 20 through the flow path L3. The first distillation tower 30 for distilling the containing polymerization mixture into the lubricating oil distillate and the distillate other than the lubricating oil distillate, respectively, and the lubricating oil distillate supplied from the first distillation tower 30 through the flow path L4 are 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 different from the lubricating oil base oil and the lubricating oil base oil. The second distillation column 50 for distilling into the distillate and the flow path L4'and / or the second distillation for merging the distillates other than the lubricating oil distillate obtained in the first distillation column 30 into the flow path L1. A flow path L6'for merging distillates other than the lubricating oil base oil obtained in the column 50 into the flow path L1 and a flow path L6 for taking out the lubricating oil base oil obtained in the second distillation tower 50 are provided. Has been done.

The type of the pyrolysis purification apparatus 10, the first reactor 20, and the second reactor 40 is not particularly limited. For example, a naphtha cracker is preferably used for the thermal decomposition purification apparatus 10, a reactor containing an ethylene polymerization catalyst and a solvent is preferably used for the first reactor 20, and a second reactor 40 is used. A fixed-bed flow reactor filled with a hydrogenation isomerization catalyst is preferably used. In the lubricating oil base oil production apparatus 100, only one of the pyrolysis purification apparatus 10, the first reactor 20, and the second reactor 40 is arranged, but a plurality of thermal decomposition purifications for thermal decomposition are arranged. The apparatus, a plurality of first reactors for an oligomerization reaction, and a plurality of second reactors for pyrolysis isomerization may be arranged in series or in parallel, respectively. Further, the number of catalyst beds 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, a heavy fraction from the bottom of the column, and a second distillation column. A light distillate can be distilled from the top of the 50 column, a lubricating oil base oil can be distilled from the middle of the column, and a heavy distillate can be distilled from the bottom of the column. Although a part or all of the solvent obtained in the distillation column 30 can be used in the thermal decomposition apparatus 10, it is preferable to purify the solvent and reuse it as a polymerization solvent. Further, in the lubricating oil base oil production apparatus 100, only one first distillation column 30 and one second distillation column 50 are arranged, but a plurality of first distillation columns are arranged depending on the fractional distillation conditions. And a plurality of second distillation columns may be arranged in series or in parallel, respectively.

Further, the lubricating oil base oil production apparatus 100 puts unreacted ethylene contained in the polymerization mixture supplied from the first reactor 20 in the subsequent stage of the first reactor 20 and in the front stage of the first distillation tower 30. A flash tank for recovery may be provided, or a decalcification tank for removing metal components such as a catalyst and a catalyst activator contained in the polymerization mixture may be provided. In some cases, the unreacted ethylene recovered in the flash tank may be partially supplied to the pyrolysis purification apparatus 10 or the first reactor 20 and reused as ethylene. From the viewpoint of keeping the polymerization reactivity of the recovered unreacted ethylene constant, a bleeding step of discharging impurities to the outside of the system may be provided in order to keep the ethylene purity in the recovered ethylene constant. Further, a solvent recovery / purification apparatus may be provided in front of the first distillation column, and the recovered solvent can be reused as a polymerization reaction solvent.

Hereinafter, the present invention will be described in more detail 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 Kasei) and 2,6-diacetylpyridine (1.2429 g, 7.6 mmol, manufactured by Tokyo Kasei), Molecular Sieve 4A (5.0 g) , A catalytic amount of paratoluenesulfonic acid was dispersed in dry toluene (60 ml), and the mixture was stirred by heating under reflux for 24 hours while removing water using a Dean Stark Water Separator.

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 1} H-NMR (600MHz, 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 (0.2401g} , 1.2mmol, manufactured by Kanto Chemical Co., Inc.) was dissolved in dehydrated tetrahydrofuran (30 ml, Aldrich), diimine compound synthesized above (I) (0.4843g, 1.2mmol) Tetrahydrofuran solution (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 to dryness from the reaction solution, and the precipitated solid was washed with dehydrated ethanol until the filtrate lost its color. Further, the washed solid was washed with dehydrated diethyl ether, and the solvent was removed to obtain an iron compound. As for the obtained iron compound, 527.0820 (calculated value: 527.0831) was obtained by FD-MS, suggesting the structure of the following iron compound (1a).

[Production Example 3: Preparation of ethylene polymerization catalyst]
A compound (42.2 mg) represented by the formula (1a) obtained in Production Example 2 and 1 equivalent of trityl tetrakispentafluorophenylborate (73.8 mg) with respect to iron were added to a 500 ml eggplant flask under a nitrogen stream. It was dissolved in 200 ml of dry toluene to prepare a solution (A). To the solution (A), 100 equivalents of a trimethylaluminum (TMA) solution was added to the compound represented by the formula (1a), and the mixture was stirred for 5 minutes to obtain a solution (B) containing a catalyst. As a ligand, the compound represented by the formula (1a) obtained in Production Example 1 is further added to the solution (B) in an amount of 0.33 equivalents to the compound represented by the above formula (2a) to provide an ethylene polymerization catalyst. A solution (C) containing the above was obtained.

<Manufacturing of lubricating oil base oil>
[Example 1]
(Pyrolysis of raw material oil)
Hydrocarbons were pyrolyzed using a pyrolyzer (EGA / PY 3030D, manufactured by Frontier Lab), a gas chromatograph device, and a thermal decomposition behavior evaluation device accompanied by a mass spectrometer. The gas generated by thermal decomposition was collected by a microjet cryotrap while being cooled by liquid nitrogen, separated by gas chromatography, and qualitatively and quantitatively analyzed by mass spectrometry. The conditions of the thermal decomposition behavior evaluation device are as follows.

-Pyrolyzer temperature: 750 ° C or 700 ° C
Dwelling time: 1 minute ・ Gas chromatograph device inlet temperature: 250 ° C
Temperature rise: 40 ° C (hold for 3 minutes) to 250 ° C (20 ° C / min, hold for 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 10-550
Scan speed: 2.7 scans / sec Ion source temperature: 230 ° C

Normal octane (manufactured by Tokyo Kasei, 1.3 mg) was thermally decomposed at 750 ° C. as a representative product of naphtha used as a raw material oil. Separation by gas chromatography, mass analysis, methane, ethylene, propylene, 1-butene, butadiene, 3-methyl-1-butene, 2-pentene, piperylene, isoprene, cyclopentadiene, cyclopentene, hexadiene, 1-hexene, cyclo Hexadiene, methylcyclopentadiene, benzene and the like were detected as thermally decomposable 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, dry toluene (7.6 L) was introduced into the autoclave under a nitrogen stream to adjust the temperature 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 dried toluene was introduced, and commercially available ethylene (large) corresponding to high-purity ethylene purified from the above-mentioned pyrolysis component was added. Industrial (> 99.5%)) manufactured by positive acid was continuously introduced under the conditions of 0 ° C. and 0.2 MPa. After 970 minutes, the introduction of ethylene was stopped, unreacted ethylene was removed, 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 4 times. A typical catalytic efficiency (CE) was 68875 Poly kg / Fe mol. The Mn of the oligomer (WAX1) obtained by mixing 4 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 regarding the normal paraffin content of WAX1 and the content of the hydrocarbon compound having an even number of carbon atoms (even number of carbon atoms content).

(Distillation of oligomers)
9293 g of the above WAX1 was introduced into a 20 L three-necked flask, and simple distillation was performed in order to collect a boiling point fraction of 250 to 500 ° C. in terms of normal pressure with a bottom temperature of 380 ° C. from room temperature and a pressure of 29 kPa from normal pressure. .. A fraction of 7470 g (lubricating oil fraction) could be collected, and the residue (distillate other than the lubricating oil fraction) was 1791 g. The Mn of the lubricating oil fraction was 470, and the Mw / Mn was 1.5. The Mn of the residue was 2000, and the Mw / Mn was 1.6.

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

(Hydrogenation isomerization reaction)
Using a zeolite-based hydrogenation isomerization catalyst adjusted to have a noble metal content of 0.1 to 5% by mass, the lubricating oil distillate obtained above has a reaction temperature of 330 ° C., a hydrogen partial pressure of 5 MPa, and a space velocity. Hydrogenation isomerization was performed under the condition of 0 LHSV to obtain an isomerized oil 1.

(Distillation of isomerized oil)
By distilling the isomerized oil 1 obtained above under reduced pressure, a fraction other than the lubricating oil base oil 1 equivalent to 70 Pale and the lubricating oil base oil 1 was obtained. Table 2 shows the properties of the obtained lubricating oil base oil 1. In Table 2, the "carbon number distribution", "average carbon number" and "even carbon number content" were obtained by performing gas chromatography analysis on the obtained lubricating oil base oil 1. Yes, the "traction coefficient" is a value measured 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 ratio of 3% using a steel ball and a steel disc as test pieces ( The same applies hereinafter).

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

(Hydrogenation isomerization reaction)
Using a zeolite-based hydrogenation isomerization catalyst adjusted to have a noble metal content of 0.1 to 5% by mass, the lubricating oil distillate obtained above has a reaction temperature of 330 ° C., a hydrogen partial pressure of 5 MPa, and a space velocity. Hydrogenation isomerization was performed under the condition of 0 LHSV to obtain an isomerized oil 2.

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

The light fraction (0.8 mg) obtained above was thermally decomposed at 750 ° C. Separation by gas chromatography, mass analysis, methane, ethylene, propylene, 1-butene, butadiene, 2-pentene, piperylene, isoprene, cyclopentadiene, cyclopentene, hexadiene, 1-hexene, cyclohexadiene, methylcyclopentadiene, benzene, etc. Was detected as a thermally decomposing component. The obtained ethylene was 10.4%, propylene was 14.5%, and butadiene was 14.9%. It has been shown that light fractions, which are lighter than the lubricating oil base oils obtained by distillation of isomerized oils, can be re-recovered with sufficient ethylene by returning to thermal decomposition.

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

(Effect of olefin on ethylene oligomerization reaction)
The following tests were conducted to investigate the effect of the presence of olefins on the catalytic efficiency of the ethylene polymerization catalyst in the ethylene oligomerization reaction.

[Reference example]
Under a nitrogen stream, the compound (1 μmol) represented by the formula (1a) and 1 equivalent of trityl tetrakispentafluorophenylborate with respect to iron were dissolved in 20 ml of dry toluene in a 50 mL eggplant flask, and the solution (D) was added. bottom. To the solution (D), 100 equivalents of a trimethylaluminum (TMA) solution was added to the compound represented by the formula (1a), and the mixture was stirred for 5 minutes to obtain a solution (E) containing a catalyst. Dry toluene (80 mL) was introduced into a 600 mL autoclave equipped with an electromagnetic induction stirrer that had been sufficiently dried at 110 ° C. under reduced pressure in advance under a nitrogen stream, and the temperature was adjusted to 25 ° C. The solution (E) was added to the above autoclave into which dry toluene was 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, 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 catalytic efficiency was 7946 kg Olig / Fe mol. The obtained oligomer had a Mn of 410, a Mw of 740, and a Mw / Mn of 1.9.

[Comparison reference example]
A semi-solid oligomer was obtained in the same manner as in Reference Example except that 1-decene (5 ml) was further added to the solution (E). The catalytic efficiency was 5186 kg Olig / Fe mol. The obtained oligomer had a Mn of 260, a Mw of 550, and a Mw / Mn of 2.1. Furthermore, 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.

From this result, it can be seen that the presence of an olefin such as 1-decene in the oligomerization reaction system lowers the catalytic efficiency of the ethylene polymerization catalyst. Distillates other than the lubricating oil distillate obtained in the first distillation step and distillates other than the lubricating oil base oil obtained in the second distillation step are used again as raw materials for the polymerization step using unreacted ethylene. For this purpose, when used as a part of raw material oil, it was shown that it is important to return to the decomposition and purification step from the viewpoint of maintaining the catalytic efficiency of the ethylene polymerization catalyst.

10 ... Pyrolysis refining equipment, 20 ... 1st reactor, 30 ... 1st distillation column, 40 ... 2nd reactor, 50 ... 2nd distillation column, 100 ... Lubricating oil base oil production equipment, L1, L2, L3, L4, L4', L5, L6, L6'... Flow path.

Claims (3)

A decomposition and refining process in which the raw material oil is thermally decomposed and the obtained thermal decomposition product is refined to obtain ethylene.
A polymerization step in which ethylene is oligomerized in the presence of an ethylene polymerization catalyst to obtain a polymerization mixture containing an ethylene oligomer.
The first distillation step of distilling the polymerization mixture into a lubricating oil fraction and a fraction other than the lubricating oil fraction, respectively.
An isomerization step of hydrogenating the lubricating oil fraction in the presence of a hydrogenation isomerization catalyst to obtain a reaction mixture containing an isomerized oil.
A second distillation step of distilling the reaction mixture into a lubricating oil base oil and a fraction other than the lubricating oil base oil, respectively, is provided.
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 is used as a part of the raw material oil. A method for producing a lubricating oil base oil, which is returned to the decomposition refining step. The method for producing a lubricating oil base oil according to claim 1, wherein the fraction other than the lubricating oil base oil obtained in the second distillation step is returned to the decomposition refining step as a part of the raw material oil. The method for producing a lubricating oil base oil according to claim 1 or 2, wherein the fraction other than the lubricating oil base oil is a light fraction lighter than the lubricating oil base oil.

Images