JP2938487B2 - Manufacturing method of lubricating base oil - Google Patents

Description

Description: TECHNICAL FIELD [0001] The present invention relates to a method for producing a high-performance lubricating base oil rich in isoparaffin and partially naphthene.

[Technical background of the invention and its problems] In recent years, along with technical development in the machine field such as automobile engines and machine tools, it has endured severe conditions and long-term use, has enabled energy saving, and has pollution problems. No high performance lubricating oil has been required.

In addition, a new lubricating oil base that can diversify crude oil replaces the conventional solvent refining method-based production method, which has to rely on expensive and high-quality specific crude oil because it is greatly affected by the type of crude oil. There is a need for an oil production method.

Hydrocracking and hydrofinishing under high pressure have been proposed as a method to satisfy such demands, and several units have already been put into operation. However, all of these have a reaction pressure of 20
0 kg / cm ² and the high pressure at which for plant construction costs Kasami, during product oil contains many undesirable polycyclic naphthenes as lubricating base oil component, whereas in the use of additives and lubricants There is a disadvantage that the content of alkylbenzene required for increasing the solubility of the generated sludge is small.

[Object of the Invention] The present invention has been made to solve such disadvantages of the conventional method, and has a high viscosity index and a low pour point using a specific raw material oil, and has excellent oxidation stability. An object of the present invention is to produce a high-performance lubricating oil base oil which has thermal stability and has a strong ability to dissolve sludge generated during use of an additive or a lubricating oil into the lubricating oil at a low cost.

[Summary of the Invention] As a result of intensive studies, the present inventors have achieved the above object by hydrocracking a specific feedstock under low pressure, low LHSV reaction conditions, and performing dewaxing and dearomatization. I found what I could achieve.

That is, the present invention relates to a vacuum distillate (WVGO), a mild hydrocracking (MHC) treated oil of WVGO (HIX), a mixed oil thereof, or a deasphalted oil (DAO) or an MHC treated oil of DAO or a mixture thereof. Oil in the presence of hydrocracking catalyst, total pressure 100-150kg / c
m ² , temperature 360 ~ 440 ℃, LHSV0.5hr- ¹ under reaction conditions,
Hydrocracking to a decomposition rate of 40 to 75 wt%, the decomposition product as it is, or a lubricating fraction is recovered and then dewaxed and then dearomatized or dearomatized After dewaxing, the total aromatic content is 2 to 15 wt%. The total content of isoparaffins and mononaphthenes in the saturated content is 60 wt% or more. The alkylbenzene content in the total aromatic content is 30 wt% or more. To produce a lubricating base oil having a composition in which the content of tri- or tetracyclic aromatics in the aromatic component is 4 wt% or less, and having a viscosity index of 105 or more and a pour point of -10 ° C or less. The present invention relates to a method for producing a lubricating base oil.

In addition, vacuum distillation distillate (WVGO), mild hydrocracking (MHC) treated oil of WVGO (HIX), or a mixed oil thereof, or deasphalted oil (DAO), or MHC treated oil of DAO, or hydrogenated mixed oil thereof Total pressure 100 in the presence of cracking catalyst
150150 kg / cm ² , temperature 360-440 ° C., LHSV0.5hr ^-1 or less under the reaction conditions, hydrocracking to a decomposition rate of 40-75 wt%, the decomposition product as it is or lubricating fraction And then dewaxing, followed by dearomatization or dewaxing followed by dewaxing, so that the total aromatic content is 3 to 15 wt%, isoparaffin and saturated naphthene in the saturated component. Has a composition in which the content of alkylbenzene in the total aromatics is not less than 30% by weight and the content of tri- and tetracyclic aromatics in the total aromatics is not more than 4% by weight; and a) 70 Pale fraction has a viscosity index of 105 or more and a pour point of -10 ° C or less. B) SAE-10 fraction has a viscosity index of 115 or more and a pour point of -10 ° C or less. C) SAE-20 fraction has a viscosity of 120 or more. Index and pour point of -10 ° C or less d) Lubricating oil base that satisfies either viscosity index of 120 or more and pour point of -10 ° C or less for SAE-30 fraction The present invention relates to a method for producing a lubricating base oil characterized by producing oil.

The feedstock used in the present invention is a vacuum distilled distillate (WVGO)
Or WVGO mild hydrocracking (MHC) treated oil (HIX) or a mixed oil thereof or deasphalted oil (DAO) or DAO MHC treated oil or a mixed oil thereof.

WVGO is a distillate obtained by distilling residual oil from an atmospheric distillation unit of crude oil with a vacuum distillation unit, preferably at 360 ° C.
It has a boiling point of ~ 530 ° C.

The above HIX and WVGO are MHC (total pressure is 100kg / cm ² or less,
Preferably 60 to 90 kg / cm ² , temperature is 370 to 450 ° C., preferably 400 to 430 ° C., LHSV is 0.5 to 4.0 hr ⁻¹ , preferably 1.0 to
Decomposition rate of 360 ° C ⁺ fraction under 20hr- ¹ reaction condition is 20 ~ 30wt
% Of heavy vacuum gas oil produced by relatively mild hydrogen cracking in the range of 0.1%).

As the catalyst of the MHC, alumina, silica alumina,
It is obtained by supporting a Group VI metal and a Group VIII metal on a composite oxide carrier such as alumina boria and sulfided. For example, a promoter such as a phosphorus compound may be added to alumina.

The supported amount of the metal is 5 to 30% by weight, preferably 10 to 25% by weight of a Group VI metal such as molybdenum, tungsten and chromium, and 1 to 10% by weight, preferably 2 to 10% by weight of a Group VIII metal such as cobalt and nickel on an oxide basis. ~ 10 wt%.

When WVGO and HIX are mixed, it is preferable to mix WVGO with HIX at 50 wt% or more.

The above-mentioned deasphalted oil is an oil which is obtained by treating a residual oil obtained by distilling a residual oil from an atmospheric distillation apparatus with a vacuum distillation apparatus by a propane deasphalting method or the like and containing substantially no asphaltenes.

Presence of feedstock hydrocracking hydrocracking catalyst used in the present invention, the total pressure is 150 kg / cm ² or less, preferably from 100 to 13
A low pressure in the 0 kg / cm ^2, temperature of three hundred sixty to four hundred forty ° C., preferably three hundred seventy to four hundred thirty ° C., LHSV is 0.5 hr ^-1 or less, preferably 0.2 to 0.
Low LHSV of 3hr- ¹ and hydrogen to feed oil ratio of 1,000 to 6,000
scf / bbl-feedstock, preferably 2,500-5,000 scf / bbl
-It can be carried out under the reaction conditions of the feedstock.

The hydrocracking rate of the feedstock used in the present invention refers to the ratio of the cracked product fraction to the feedstock, and the value is at least 40 wt%, preferably at least 45 wt%, more preferably at least 50 wt%. When HIX is used as a feedstock, the total decomposition rate of MHC and hydrocracking is selected to be 60 wt% or more, preferably 70 wt% or more. When a part of the uncracked oil is recycled, the cracking rate referred to here is not a cracking rate including recycled oil but a cracking rate per fresh feed.

The hydrocracking catalyst used in the present invention preferably has a dual function.Specifically, for example, a hydrogenation point composed of a Group VIb metal and a Group VIII iron group metal;
A catalyst having a decomposition point composed of a complex oxide of Group IV, IV and V elements may be mentioned. The Group VIb metals include tungsten and molybdenum, and the Group VIII iron group metals include nickel, cobalt and iron. These are finally used as sulfides after being supported on the composite oxide carrier.

As the composite oxide used for the carrier, silica alumina,
There are silica zirconia, silica titania, silica magnesia, silica alumina zirconia, silica alumina titania, silica alumina magnesia, etc., and crystalline silica alumina (zeolite), crystalline alumina phosphate (ALPO), crystalline silica alumina phosphate (SAP
O) is sometimes used.

The amount of the metal supported on the composite oxide is 5 to 30% by weight, preferably 10 to 25% by weight for Group VIb metal on an oxide basis.
%, For the Group VIII iron group metal, 1 to 20 wt%, preferably 5 to
15 wt%. In addition, desulfurization before the hydrocracking catalyst,
A pretreatment catalyst having excellent denitrification ability may be filled. The pretreatment catalyst is obtained by supporting a Group VI metal and a Group VIII metal on a support such as alumina or alumina boria and sulphidizing the support. Promoter for alumina and alumina boria,
For example, a phosphorus compound may be added.

In the present invention, after the hydrocracking, a lubricating oil fraction may be recovered from the cracked product by a usual distillation operation. The lubricating oil fraction is a 70-peer fraction having a boiling range of 343 ° C. to 390 ° C., a SAE-10 fraction at 390 ° C. to 445 ° C., and a S
The AE-20 fraction and the SAE-30 fraction at 500 ° C to 565 ° C are recovered as a lubricating oil fraction.

In the present invention, the hydrocracked oil is then subjected to a dewaxing treatment, followed by a dearomatic treatment, or a dewaxing treatment, followed by a dewaxing treatment. Examples of the dewaxing treatment include a solvent dewaxing treatment and a contact dewaxing treatment.

The solvent dewaxing treatment can be performed in a normal direction. An example is the MEK method. The MEK method uses benzene, toluene, acetone or a mixed solvent such as benzene, toluene, and methyl ethyl ketone (MEK) as a solvent.
The processing conditions adjust the cooling temperature so that the dewaxed oil has a predetermined pour point. Solvent / oil vol ratio is 0.5-5.0, preferably
1.0 to 4.5, temperature is -5 to -45 ° C, preferably -10 to -40
° C.

The contact dewaxing treatment can be performed by a usual method. For example, using a pentasil-type zeolite as a catalyst, the reaction temperature is adjusted so that the dewaxed oil has a predetermined pour point under hydrogen flow.

The reaction conditions under the hydrogen flow is the total pressure is 10 to 70 kg / cm ^2,
Preferably it is 20 to 50 kg / cm ² , and the temperature is 240 to 400 ° C, preferably 260 to 380 ° C. LHSV is 0.1-3.0 hr ^-1 , preferably
It is in the range of 0.5 to 2.0 hr ^-1 .

Examples of the dearomatization treatment include a solvent dearomatization treatment and a high-pressure hydrogenation dearomatization treatment.

In the solvent dearomatization treatment, usually a solvent such as furfural and phenol is used, but in the present invention, it is preferable to use furfural as the solvent. The conditions of the solvent dearomatization treatment are as follows: the solvent / oil vol ratio is 4 or less, preferably 3 or less, more preferably 2 or less, and the temperature is 90 to 150 ° C., and the raffinate yield is 60 vol% or more, preferably 70 vol%. The operation is performed so as to be at least 85 vol%, more preferably at least 85 vol%.

In the presence of a dearomatization process by the high-pressure hydrogenation reaction was usually the first VI b group metals and Group VIII iron group metals on an alumina support carrying sulfided catalyst, the total pressure 150~200kg / cm ^2, preferably 170 to 200 kg / cm ^2, temperature of 280 to 350 ° C., preferably 300
~ 330 ° C, LHSV is 0.2 ~ 2.0hr- ¹ , preferably 0.5 ~ 1.0hr
^{Performed under} the condition of ^-1 . The amount of the metal supported is 5 to 30 wt%, preferably 10 to 25 wt% for Group VIb metals such as molybdenum, tungsten and chromium, and 1 to 10 wt% for Group VIII iron group metals such as cobalt and nickel on an oxide basis. %, Preferably 2 to 10% by weight.

In the present invention, the dearomatization treatment preferably uses a solvent dearomatization treatment.

In the present invention, when a solvent dearomatization process is used as the dearomatization process, a hydrogenation process can be performed after this process if necessary. The hydrogenation treatment is a solvent dearomatized oil, the total reaction pressure 50 kg / cm ² or less, preferably 25 ~ 40 kg
of / cm ² at low pressure hydrogenation reaction conditions, the VI b alumina support
It is carried out by supporting a group metal and a group VIII iron group metal and bringing them into contact with a hydrogenation catalyst obtained by sulfidation. The supported amount of the metal is a Group VIb metal on an oxide basis, for example, molybdenum,
5-30 wt% of tungsten and chromium, preferably 10-25
wt%, Group VIII iron group metals such as cobalt and nickel are from 1 to 10 wt%, preferably from 2 to 10 wt%.

Such hydrotreatment under relatively low pressure dramatically improves the photostability of the solvent-dearomatized oil.

In the present invention, if necessary, the total aromatic content in the base oil may be reduced to 1 wt% or less only for special uses. This operation is usually performed after the solvent dearomatization treatment, preferably at a reaction pressure.
80~150kg / cm ^2, the reaction temperature 250~350 ℃, LHSV0.2~2.0hr
Under the conditions of ^-1, a group VIb metal and a group VIII
It is achieved by hydrogenation over a sulfided catalyst carrying a group III metal. As the catalyst used here, the same catalyst as the above-mentioned hydrotreating catalyst under low pressure can be used.

In the present invention, when the lubricating oil fraction is not recovered after hydrocracking, the lubricating oil fraction may be recovered by a normal distillation operation after the dearomatization treatment or the dewaxing treatment or the hydrogenation treatment. Good. The lubricating oil fraction collected here is, as in the previous case, a 70-pale fraction having a boiling range of 343 ° C to 390 ° C, a SAE-10 fraction of 390 ° C to 445 ° C, and a S
AE-20 fraction, SAE-30 fraction at 500 ° C to 565 ° C, and the like.

In the present invention, by performing the above processing,
A lubricating base oil having the following lubricating oil composition and performance can be produced from a base oil. That is, the lubricating base oil has the following compositional characteristics.

a) The total aromatic content, which is the total amount of aromatic components, is 2 to 15 wt.
%, Preferably in the range of 3 to 10% by weight.

b) The total amount of isoparaffin and mono-naphthene in the saturated content is as high as 60% by weight or more, preferably 65% by weight or more.
These components are highly preferred lubricating base oil components because they have a high viscosity index and excellent oxidation stability and heat stability.

c) the amount of alkylbenzene in the total aromatic content is 30% by weight or more;
Preferably, it takes a value of 40% by weight or more. Alkyl benzene is a very preferable lubricating base oil component because it has a strong power to dissolve sludge generated during use of additives and lubricating oil in lubricating oil and has a high viscosity index.

d) The amount of tri- or tetracyclic aromatics in the total aromatics is suppressed to 4% by weight or less, preferably 3% by weight or less. The inventors have found that there is a clear negative correlation between the tri- or tetracyclic aromatic content in the finished base oil and the thermal stability of the base oil (see attached drawings). The present inventors have found that the solvent dearomatization treatment of the lubricating oil fraction of the present invention produced under medium-low pressure, low LHSV hydrocracking reaction conditions can be carried out by three-, four-ring aromatic, and five-ring ⁺ aromatic. It has also been found that the selectivity to polycyclic aromatic components such as polycyclic aromatic components is extremely high, and the polycyclic aromatic components can be efficiently extracted and removed without significantly reducing the alkylbenzene content.

Further, the performance of the lubricating base oil has a viscosity index of 105 or more and −1
It has a pour point of 0 ° C. or less and has the following performance for various lubricating base oils.

The 70-pale fraction has a viscosity index of 105 or more, preferably 110
As described above, it has high performance with a pour point of -10 ° C or less, preferably -25 ° C or less.

The SAE-10 fraction has a viscosity index of 115 or more, preferably 125
As described above, the pour point has a high performance of −10 ° C. or less, preferably −15 ° C. or less.

The SAE-20 fraction has a viscosity index of 120 or more, preferably 125
As described above, the pour point has a high performance of −10 ° C. or less, preferably −15 ° C. or less.

The SAE-30 fraction has a viscosity index of 120 or more, preferably 125
As described above, the pour point has a high performance of −10 ° C. or less, preferably −15 ° C. or less.

[Effects of the Invention] By using the method of the present invention, a high-performance lubricating base oil containing a large amount of isoparaffins, mono-naphthenes, and alkylbenzenes which are preferable as lubricating oil components, and a small amount of polycyclic naphthenes and polycyclic aromatics which are not preferable as lubricating oil components, It can be manufactured at low cost.

Therefore, it has a high viscosity index and a low pour point, has excellent oxidation stability and thermal stability, and has a strong ability to dissolve sludge generated during use of additives and lubricating oil in lubricating oil. A lubricating base oil can be produced.

Hereinafter, the effectiveness of the present invention will be described with reference to Examples and Comparative Examples. Table 1 shows the properties of the feedstock oils used in the examples and comparative examples.

Example 1 According to the method of the present invention comprising a hydrocracking treatment, a solvent dewaxing treatment, and a solvent dearomatization treatment using a furfural solvent under the conditions of medium pressure and low LHSV shown in Table 2, a lubricating base oil was produced. Manufactured.

As a result, SAE-10 grade product base oil produced from WVGO raw material has a high aromatic content of 9.5 wt%, and therefore has excellent solubility of additives and solubility of sludge generated during use. In addition, since the total amount of isoparaffin and mononaphthene having a high viscosity index in the saturated component is relatively large at 66.1 wt%, the viscosity index of the base oil is as high as 122. Furthermore, there is hardly any tri-, tetra-aromatic, or pentacyclic ⁺ aromatic family remaining in the aromatic component, which degrades the stability of the base oil, and easily passes the thermal stability test. The raffinate yield at this time was 90.2
It is as high as wt% and contains a large amount of alkylbenzene which is a desirable component.

Example 2 When the dewaxed oil obtained in Example 1 was subjected to dearomatization treatment using a furfural solvent at a solvent / oil volume ratio of 3.0, the amount of tri- or tetracyclic aromatics in the aromatic components was reduced to a trace amount. However, the ASTM color in the thermal stability test is also stable at L2.5. As described above, hydrocracked oils under medium and low pressures and low LHSV have excellent selectivity to polycyclic aromatics in the solvent dearomatization treatment.

Example 3 A lubricating base oil was produced by the method of the present invention comprising hydrocracking treatment, solvent dewaxing treatment and solvent dearomatization treatment under the conditions of medium pressure and low LHSV shown in Table-2. .

As a result, the SAE-10 grade product base oil produced from the HIX raw material has a high aromatic content of 6.1% by weight, and therefore has excellent solubility of additives and solubility of sludge generated during use. Further, since the total amount of the isoparaffin and the mononaphthene having a high viscosity index in the saturated content is as large as 70.1% by weight, the viscosity index of the base oil shows a very high value of 127. Furthermore, the three are in the aromatic fraction to deteriorate the stability of the base oil, tetracyclic aromatic pentacyclic ⁺ aromatics are not remain most readily pass the thermal stability test. The raffinate yield at this time was 91.8
It is as high as wt% and contains a large amount of alkylbenzene which is a desirable component.

Example 4 The hydrocracked oil obtained in Example 3 was subjected to high pressure, medium
When hydrogenated under LHSV conditions, the amount of tri- or tetracyclic aromatics in the aromatics drops to 0.8 wt% (0.1 wt% in the product base oil) and easily passes the thermal stability test.

Example 5 When the lubricating base oil obtained in Example 3 is subjected to hydrofinishing treatment under the low pressure conditions shown in Table 2, tri-, tetra-cyclic aromatic, and pentacyclic ⁺ Aromatic and resin content is reduced, and light stability is improved for up to 4 days. As described above, the hydrogenated oil under the low pressure condition has a remarkably improved light stability.

Example 6 The lubricating base oil obtained in Example 3 was subjected to medium pressure and medium LH shown in Table-2.
Hydrofinishing under SV conditions reduces the aromatics to 0.7 wt%.

Example 7 The hydrocracked oil obtained in Example 3 was subjected to MEK dewaxing treatment at a solvent / oil vol ratio of 2.0 and a dewaxing temperature of 40 ° C. and to dearomatization treatment using a furfural solvent under the conditions shown in Table-2. The pour point of the finished base oil drops to -35 ° C. At this time, the total amount of isoparaffins and saturated naphthenes in the saturated content was 67.1 wt%
Therefore, the viscosity index of the base oil shows a high value of 121. Furthermore, there are hardly any tri-, tetra-cyclic aromatics and penta-rings ⁺ aromatics remaining, which easily pass the thermal stability test.

Example 8 The present invention comprises a hydrocracking treatment under the conditions of medium pressure and low LHSV shown in Table-2, a catalytic dewaxing treatment under the conditions shown in Table-2, and a solvent dearomatization treatment using a furfural solvent. A lubricating base oil was produced by the method.

As a result, the SAE-10 grade product base oil produced from the HIX raw material has a high aromatic content of 6.8% by weight, and therefore has excellent solubility of additives and solubility of sludge generated during use. In addition, since the total amount of isoparaffin and mononaphthene having a high viscosity index in the saturated content is as large as 68.0% by weight, the viscosity index of the base oil is as high as 123. Furthermore, the three are in the aromatic fraction to deteriorate the stability of the base oil, tetracyclic aromatic, pentacyclic ⁺
Almost no aromatic remains, and on the contrary, a large amount of the desired component alkylbenzene is contained.

Example 9 Production of a lubricating base oil by the method of the present invention comprising hydrocracking, solvent dewaxing, and solvent dearomatization using a furfural solvent under the conditions of medium pressure and low LHSV shown in Table-2 Was done.

As a result, the product base oil of SAE-10 grade produced from DAO raw material has a high aromatic content of 7.8 wt%, and therefore has excellent solubility of additives and solubility of sludge generated during use. In addition, since the total amount of isoparaffin and mononaphthene having a high viscosity index in the saturated component is relatively large at 65.1 wt%, the viscosity index of the base oil is as high as 121. further,
In the aromatic components, there are hardly any three, four or four ring aromatics and five ring ⁺ aromatics, which degrade the stability of the base oil, and on the contrary, a large amount of alkylbenzene which is a desirable component is contained.

Comparative Example 1 A lubricating base oil was produced by a method comprising hydrocracking under high pressure and high LHSV conditions and solvent dearomatization using a furfural solvent as shown in Table-3.

As a result, the SAE-10 grade product base oil produced from WVGO feedstock has a low aromatic content of 3.8 wt%, and therefore poor solubility of additives and solubility of sludge generated during use. In addition, since the total amount of isoparaffin and high-grade naphthene having a high viscosity index in the saturated component is still not enough, 55.4 wt%, the viscosity index of the base oil is as low as 110. Furthermore, the three are in the aromatic fraction to deteriorate the stability of the base oil, tetracyclic aromatic, and remained a lot pentacyclic ⁺ aromatics content of the alkylbenzene is small is desirable components.

Comparative Example 2 A dewaxed oil obtained by solvent dewaxing of a hydrocracked base oil obtained by treatment under high pressure and high LHSV shown in Table 3 does not pass the thermal stability test.

Comparative Column 3 The solvent dewaxed oil obtained in Comparative Example 2 was subjected to a solvent / oil vol ratio of 2.0,
Even if the solvent is dearomatized using a furfural solvent, as much as 8.1 wt% (0.3 wt% in the product base oil) of the three- or four-ring aromatics remain in the aromatics and pass the thermal stability test. Does not reach.

Comparative Example 4 The solvent dewaxed oil obtained in Comparative Example 2 was prepared at a solvent / oil vol ratio of 3.0.
Only after the solvent dearomatization treatment using furfural solvent, the amount of tri- or tetracyclic aromatics in the aromatics drops to 6.0 wt% (0.2 wt% in the product base oil) and passes the thermal stability test. Become like However, at this time, since the saturated component and the alkylbenzene are also extracted and removed at the same time, the raffinate yield is as low as 72.1 wt%, and the content of alkylbenzene, which is a desirable component, is small. Thus, hydrocracked oils under high pressure and high LHSV have poor selectivity to polycyclic aromatics in solvent deodorization treatment.

Comparative Example 5 The dewaxed oil obtained by solvent dewaxing of the hydrocracked oil under medium to low pressure and low LHSV as in Example 1 does not pass the thermal stability test as it is.

[Brief description of the drawings]

The accompanying drawings are graphs showing the relationship between the tri- or tetracyclic aromatic content and the thermal stability of the lubricating oil.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // C10G 45/64 C10G 45/64 47/12 47/12 73/08 73/08 C10N 30:02 30:10 (56) References JP-A-55-65295 (JP, A) JP-B-51-5403 (JP, B1) US Patent 3,970,543 (US, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G10G 67 / 14 G10G 67/04 G10G 65/12 G10G 21/16 G10G 47/12 G10G 45/64 G10G 73/08 G10M 101/02

Claims (4)

(57) [Claims] Claims 1. A vacuum distilled distillate (WVGO) or WVGO is treated with a mild hydrocracking (MHC) treated oil (HIX) or a mixture thereof, or a deasphalted oil (DAO) or a DAO MHC treated oil or a mixed oil thereof. Total pressure in the presence of hydrocracking catalyst
Under the reaction conditions of 100-150 kg / cm ² , temperature of 360-440 ° C, LHSV of 0.5 hr ^-1 or less, hydrocracking is performed so that the decomposition rate becomes 40-75 wt%. The fraction is recovered, then dewaxed, dearomatized, or dearomatized, and then dewaxed so that the total aromatic content is 2 to 15% by weight. The total content of naphthenes is 60% by weight or more. The alkylbenzene content in the total aromatic content is 30% by weight or more. The total aromatic content of the tri- or tetracyclic aromatic content is 40% by weight or less. A method for producing a lubricating base oil, comprising producing a lubricating base oil having a viscosity index of 105 or more and a pour point of -10 ° C or less. 2. A vacuum distilled distillate (WVGO) or WVGO is treated with a mild hydrocracking (MHC) treated oil (HIX) or a mixture thereof, or a deasphalted oil (DAO) or a DAO MHC treated oil or a mixed oil thereof. Total pressure in the presence of hydrocracking catalyst
Under the reaction conditions of 100-150 kg / cm ² , temperature of 360-440 ° C, LHSV of 0.5 hr ^-1 or less, hydrocracking is performed so that the decomposition rate becomes 40-75 wt%. The fraction is recovered, then dewaxed, dearomatized, or dearomatized, and then dewaxed so that the total aromatic content is 2 to 15% by weight. The total content of naphthenes is 60 wt% or more. The alkylbenzene content in the total aromatic components is 30 wt% or more. The tri- or tetracyclic aromatic content in the total aromatic components is 40 wt% or less, and a) Viscosity index of 105 or more and pour point of -10 ° C or less for 70 pale fraction b) Viscosity index of 115 or more and pour point of -10 ° C or less for SAE-10 fraction c) 120 for SAE-20 fraction Viscosity index above and pour point below -10 ° C d) SAE-30 fraction satisfies either viscosity index above 120 and pour point below -10 ° C Method for producing a lubricant base oil, characterized in that to produce a lubricating oil base oil. 3. The method according to claim 1, wherein in the solvent dearomatization treatment, furfural is used as a solvent and the solvent / feed oil ratio is 2 or less. 4. The method according to claim 1, wherein the raffinate yield in the solvent dearomatization treatment is 85% by weight or more.