JP3079091B2 - Rubber process oil and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process oil to be added to a natural rubber or a synthetic rubber and a method for producing the same, and in particular, has low toxicity and carcinogenicity due to a low content of a polycyclic aromatic compound. And a method for producing the same.

[0002]

2. Description of the Related Art Rubber process oils are used to facilitate rubber production operations such as kneading, extrusion, molding, etc., by utilizing the permeability of a rubber polymer structure. It is also used to improve the physical properties of rubber products. Such a rubber process oil needs to have a suitable affinity for rubber. On the other hand, rubber to be processed includes natural rubber and synthetic rubber, and there are various types of synthetic rubber. Among these, in particular, since natural rubber and styrene-butadiene rubber (SBR) are used in large amounts, rubber process oils containing a large amount of aromatic hydrocarbons and having high affinity for rubber are generally used. .

In order to obtain such a rubber process oil,
A lubricating oil fraction obtained by vacuum distillation of crude oil, a residue obtained under reduced pressure distillation, followed by dewaxing or hydrorefining if necessary, and then an oil obtained by sulfuric acid refining, or aromatic An oil obtained by extracting the oil with a solvent having an affinity for hydrocarbons is used. Rubber process oil obtained in this way contains 70 to 99 percent of the aromatic compound according to the column chromatography, the accordance if% C _A value Kurtz method ring analysis 20-50
% Of dimethylsulfoxide (DMSO) extract corresponding to the content of polycyclic aromatic compounds (PCA) as defined by the British Petroleum Institute.

[0004] However, in recent years, the carcinogenicity of PCA has been regarded as important, and in Europe, oils containing 3% or more of PCA are required to be toxic, and there is a movement to restrict the use. Therefore, there is an urgent need to reduce the PCA content of rubber process oils to less than 3%.

With respect to rubber process oils having a PCA content of less than 3%, Japanese Patent Application Laid-Open No. 6-505524 discloses a process in which a residue obtained by distillation under reduced pressure is subjected to dehistory treatment, and the obtained oil is dewaxed to obtain PCA.
Disclosed is a process for producing a rubber processing oil with an A content reduced to less than 3%. JP-A-7-501346 discloses a non-carcinogenic bright stock extract and PCA.
Disclosed is a low-history oil and a process for producing the same, in which an oil obtained by extracting a residue in a vacuum distillation column or an aromatic compound is reduced by an extraction treatment of a de-historized oil or a dewaxing process thereof. The oil obtained from is used.

The above oils have lower PCA content but higher aniline point. The aniline point is an index of the content of the aromatic hydrocarbon, and a high aniline point means that the content of the aromatic hydrocarbon is low. However, as the aromatic hydrocarbon content in the oil decreases, the affinity of the oil for rubber decreases. Therefore, in the technology disclosed in the above publication, the properties required for the rubber process oil, that is, the permeability of the rubber process oil to the rubber polymer is reduced. Also, it is difficult to satisfy the physical condition of the final rubber product.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve such problems of the prior art. The first object of the present invention is to provide a rubber process having high safety and high permeability to a rubber polymer. Oil and its manufacturing process.

A second object of the present invention is to provide a rubber product excellent in safety without lowering the processability of the rubber and without lowering the physical properties of the rubber product. .

A third object of the present invention is to provide a novel method for producing a rubber process oil as described above.

[0010]

Means for Solving the Problems In order to achieve the above object, the present inventors have conducted intensive studies, and as a result, have found that the content of polycyclic aromatic compounds is less than 3% and the content of aromatic hydrocarbons is abundant. The present inventors have found that it is possible to provide a rubber process oil, and have accomplished the present invention.

The rubber process oil of the present invention has a polycyclic aromatic compound content of less than 3% by mass as determined by the IP346 method, an aniline point of 80 ° C. or less, and a% determined by ring analysis according to the Kurz method. C _a value of 20-50%.

Further, according to one aspect of the present invention, the method for producing a rubber process oil is selected from the group consisting of a lubricating oil fraction obtained by vacuum distillation of crude oil and a dehistory oil obtained by degassing a vacuum distillation residue of crude oil. A raw material preparation step for preparing a raw oil to be prepared, and a solvent for extracting the raw oil with a solvent having a selective affinity for an aromatic hydrocarbon to obtain a first raffinate and a mixture of the solvent and the first extract An extraction step, and a cooling step of cooling the mixture of the solvent and the first extract to separate it into a second raffinate and a mixture of the second extract and the solvent. The cooling conditions are determined so that the determined polycyclic aromatic compound content of the second raffinate is less than 3% by mass.

According to another aspect of the present invention, a method for producing a rubber process oil comprises a lubricating oil fraction obtained by vacuum distillation of crude oil and a de-historized oil obtained by de-historying a vacuum distillation residue of crude oil. A raw material preparation step of preparing the selected raw oil; and a solvent extraction step of solvent-extracting the raw oil with a solvent having a selective affinity for aromatic hydrocarbons, wherein the solvent extraction step is determined by the IP346 method. The extract to be used has a polycyclic aromatic compound content of less than 3% by mass and an aniline point of 8
It is characterized in that extraction conditions are determined so as to be 0 ° C. or less.

According to another aspect of the present invention, the process for producing a rubber process oil is selected from the group consisting of a lubricating oil fraction obtained by vacuum distillation of petroleum and a de-historized oil obtained by de-historying a vacuum distillation residue of petroleum. Extraction step of preparing a base oil, and solvent extraction of the base oil with a solvent having selective affinity for aromatic hydrocarbons to obtain a first raffinate and a mixture of the solvent and the first extract Cooling the mixture of the solvent and the first extract to separate it into a second raffinate and a mixture of the second extract and the solvent, wherein the mixture has a 90% yield with respect to the first extract. And a cooling step of obtaining a second raffinate.

According to still another aspect of the present invention, a method for producing a rubber process oil comprises a group consisting of a lubricating oil fraction obtained by vacuum distillation of petroleum and a dehistory oil obtained by degassing the residue of vacuum distillation of petroleum. A raw material preparation step of preparing a raw material oil selected from:
The raw material oil is extracted with a solvent having a selective affinity for aromatic hydrocarbons at an extraction temperature of 135 ° C. or more to separate it into raffinate and extract, and the yield of the extract is represented by the following formula (1). Adjust to meet.

Y> 33W + 6 (1) (wherein, in the formula (1), Y represents the yield (% by mass) of the extract, and W represents the polycyclic aromatic material of the raw material oil determined by the IP method. The compound content (% by mass) is shown.)

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail.

Process oils can generally be prepared from petroleum, particularly lubricating oil fractions obtained from petroleum. The lubricating oil fraction can be obtained as a fraction obtained by distilling the residual oil obtained after atmospheric distillation of petroleum under reduced pressure or as a de-historized oil obtained by dedigesting the residual oil obtained by distilling petroleum under reduced pressure. Contains a large amount of group compounds. Since such a lubricating oil content contains a large amount of polycyclic aromatic compound (PCA), a suitable process oil can be obtained if PCA can be removed from the lubricating oil.

Solvent extraction is a method for separating constituent components from oil. If a solvent having a selective affinity for an aromatic hydrocarbon compound is used in the solvent extraction of the oil, the aromatic hydrocarbon can be separated from the oil. Can be. However, solvents having selective affinity for aromatic hydrocarbon compounds are PCA
Has a higher affinity for a large amount of PCA even when an aromatic hydrocarbon compound is extracted by a general extraction operation.
Is included.

The inventors of the present application have studied on a process for producing an oil having a small amount of polycyclic aromatics and a large amount of aromatic hydrocarbons, and have found that the oil can be effectively produced by improving the solvent extraction.

In accordance with the present invention, two embodiments of the novel process are presented, in each of which improved solvent extraction using a solvent having a selective affinity for aromatic hydrocarbon compounds. Using a high-boiling aromatics-rich oil fraction as a feedstock, a suitable rubber processing oil is produced which is sufficiently rich in aromatic hydrocarbon compounds but low in PCA content.

In a first embodiment of the method for producing a rubber process oil, a lubricating oil fraction obtained from petroleum by vacuum distillation or a dehistory oil fraction obtained by dehistory of petroleum distillate bottoms is The mixture is treated with a solvent having an affinity for aromatic hydrocarbons, the mixture of the solvent and the extract (first extract) is cooled, and the polycyclic aromatic compound content of the second raffinate separated at this time Is set so that is less than 3%. That is, the feature of the first embodiment is that the extract (first extract) separated by the solvent extraction of the raw material oil is cooled to a temperature lower than the extraction temperature, and further extracted (second extract) and raffinate (second extract). 2 raffinate) and recovering the second raffinate.

In a second embodiment of the method for producing a rubber process oil, a lubricating oil fraction obtained from petroleum by vacuum distillation or a dehistory oil fraction obtained by dehistory of a petroleum distillation residue is When treated with a solvent having an affinity for aromatic hydrocarbons, the resulting extract has a polycyclic aromatic compound content of less than 3% by mass and an aniline point of 80 ° C.
Adjust the extraction conditions so that: That is, the feature of the second embodiment resides in that the extraction conditions are controlled so that the base oil is extracted at a higher temperature and the extract is recovered at a specific appropriate extraction rate.

The process oils obtained by each of these production process embodiments are most suitable as rubber process oils that have low polycyclic aromatic compound content and are rich in aromatic hydrocarbons.

The PCA content used in the present application refers to the content of an aromatic compound extracted with DMSO (dimethyl sulfoxide) according to the IP346 method defined by the British Petroleum Institute. The conventional PCA rules are 3
Some refer to aromatic compounds having more than one ring,
The IP346 method is a recognized and standard method for determining the PCA content of oil materials.

The rubber process oil obtained in the present invention has a very low content of polycyclic aromatic compounds, but a higher aromatic hydrocarbon content than conventional rubber process oils. High permeability and rubber processability does not decrease. In addition, the rubber process oil of the present invention is made of a material sufficient to obtain a rubber capable of exhibiting almost the same physical properties as a rubber product obtained by treating with a conventional process oil containing a large amount of PCA. is there.

Hereinafter, a first embodiment of the manufacturing method of the present invention will be described in detail.

In order to produce the rubber process oil of the present invention, the feedstock oil, that is, a lubricating oil fraction such as a heavy fraction obtained from petroleum, or a petroleum distillation residue (for example, a vacuum distillation residue) is used. The de-historized oil fraction obtained by de-historying is treated with a solvent having a selective affinity for aromatic hydrocarbons to remove the raffinate (first raffinate), thereby converting the first extract with the solvent. Obtained in the form of a mixture. Then, the mixture of the first extract and the solvent is cooled to separate the second raffinate, from which a rubber process oil is obtained.

The petroleum includes various crude oils such as paraffin crude oil, naphthalene crude oil, etc., and includes heavy fractions obtained by vacuum distillation of all kinds of crude oils and history obtained from vacuum distillation residues of all kinds of crude oils. Oils and the like can be used as starting materials in the present invention. Such a heavy fraction or de-historized oil may be further extracted with a solvent having an affinity for aromatic hydrocarbons and subjected to hydrorefining and dewaxing treatments as necessary. Of course, they may be used after adjusting the viscosity by mixing them. Petroleum, the raw material from which the lubricating oil fraction is obtained, is not limited to crude oil, but any oil material rich in high-boiling aromatic compounds, such as pyrolysis oil of plastics, waste oil, or a mixture of recovered oils. Can be.

As a solvent having a selective affinity for an aromatic hydrocarbon used for extracting a heavy fraction or a deasphalted oil, one or more solvents selected from furfural, phenol and N-methyl-2-pyrrolidone are selected. Can be used. Among them, furfural is most preferred.

In the above-mentioned extraction treatment with the solvent, one or more selected from a lubricating oil fraction obtained from petroleum and a deasphalted oil obtained by deasphalting a distillation residue of petroleum are mixed with 6
At a temperature of 0 ° C or more, preferably 60 to 150 ° C, 1/1
Contact the solvent with a solvent / oil ratio (volume ratio) of １ ／ to remove the first raffinate. This raffinate can be used as a general lubricating base oil material. The obtained mixture of the first extract and the solvent is sent to the next step. Since the yield of the first raffinate varies depending on the composition of the lubricating oil fraction, and the lubricating oil fraction also varies depending on the state of the petroleum or crude oil used, the extraction conditions are not constant. However, the yield of the first raffinate is generally 45% by volume or more,
Preferably 50-85% by volume, more preferably 55-8%
It was found that a suitable extract was obtained at 0% by volume. Therefore, the yield of the first extract is 55% by volume or less, preferably 5 to 55% by volume, more preferably 1% by volume.
The extraction conditions are adjusted to be 5 to 50% by volume, most preferably 30 to 45% by volume.

When the yield of the first extract exceeds 55% by volume, the amount of the non-aromatic compound contained in the extract increases, and the aromatic hydrocarbon concentration of the second raffinate obtained through the subsequent steps is increased. Becomes lower. When the yield of the first extract is less than 5% by volume, the first raffinate may not be used as a general lubricating base oil material.

When the mixture of the first extract and the solvent is cooled, the second raffinate separates from the solvent mixture. By removing the second raffinate and removing a small amount of the solvent contained therein, the second raffinate can be obtained as a desired product of the present invention.

The cooling conditions greatly affect the yield of the second raffinate and its polycyclic aromatic compound content. The composition of the first extract depends on the solvent extraction conditions and the starting material PC.
Since the concentration differs depending on the A concentration, the cooling conditions suitable for reducing the polycyclic aromatic compound concentration of the second raffinate to less than 3% by mass are not constant, but are determined by the PCA content of the first extract.

For example, when the polycyclic aromatic compound concentration of the first extract is 20 to 30% by mass, the temperature is set to be about 10 to 110 ° C. lower than the solvent extraction treatment temperature, whereby the polycyclic aromatic compound of the second raffinate is obtained. Aromatic compound concentration is 3% by mass
Less than. At this time, the second for the first extract
The raffinate yield is about 20-50%. The polycyclic aromatic compound concentration of the first extract is 3 to 10% by mass.
In the case of, the temperature is about 20 to 130
C. set lower, so that the polycyclic aromatic compound concentration of the second raffinate is less than 3% by mass. In this case, the yield of the second raffinate based on the first extract is about 50.
９０90%.

The second raffinate thus obtained is rich in aromatic hydrocarbons, the aniline point of the oil product is below 80 ° C., and the% of the ring analysis by the Kurz method is
C _A value is 20-50%. % C _A value of the ring analysis by Kurtz method is used as an index of the proportion to the total carbon content of carbon atoms constituting the aromatic ring. Since the second raffinate is formed from an extract with a solvent having an affinity for an aromatic compound, the aromatic hydrocarbon concentration of the second raffinate does not decrease so much.

[0037] In use of the rubber process oil, the% C _A value of the ring analysis by Kurtz method is less than 20%, the physical properties of the rubber product may become difficult to produce a rubber using a rubber process oil May drop. On the other hand, when the% C _A value of the ring analysis by the Kurz method exceeds 50%, the physical properties of the rubber product may also deteriorate. In view of these,% C _A value of the second raffinate from 20 to 50
%, Preferably 25-45%, more preferably 25-4%
Should be 0%.

Next, a second embodiment of the manufacturing method of the present invention will be described in detail.

In the second embodiment, the raw oil is obtained by removing the lubricating oil fraction such as a heavy fraction obtained from petroleum, or a petroleum distillation residue (for example, vacuum distillation residue). The de-historized oil fraction is treated with a solvent having a selective affinity for aromatic hydrocarbons to give a raffinate (first
Raffinate) to obtain a first extract, from which a rubber process oil is obtained.

The petroleum includes various crude oils such as paraffin crude oil, naphthalene crude oil, etc., heavy fractions obtained by vacuum distillation of all kinds of crude oils, and history obtained from vacuum distillation residues of all kinds of crude oils. Oils and the like can be used as starting materials in the present invention. Such a heavy fraction or de-historized oil may be further extracted with a solvent having an affinity for aromatic hydrocarbons and subjected to hydrorefining and dewaxing treatments as necessary. Of course, they may be used after adjusting the viscosity by mixing them. Petroleum, the raw material from which the lubricating oil fraction is obtained, is not limited to crude oil, but any oil material rich in high-boiling aromatic compounds, such as pyrolysis oil of plastics, waste oil, or a mixture of recovered oils. Can be.

One or more solvents selected from furfural, phenol and N-methyl-2-pyrrolidone are selected as solvents having a selective affinity for aromatic hydrocarbons used for extracting heavy fractions or deasphalted oils. Can be used. Among them, furfural is most preferred.

In the above-mentioned extraction treatment with a solvent, one or more selected from a lubricating oil fraction obtained from petroleum and a deasphalted oil obtained by deasphalting a petroleum distillate residue are subjected to about 135 to 150 ° C. At the top temperature of the solvent and in a solvent / oil ratio (volume ratio) of 1/1 to 1/4.

The mixture of the extract and the solvent obtained by this treatment is separated into the solvent and the extract, and this is used for a rubber process oil.

In this solvent extraction, the extraction conditions are controlled to reduce the yield so that the content of the polycyclic aromatic compound in the extract is less than 3% by weight and the aniline point is 80 ° C. or less, preferably 70 ° C. or less. adjust.

The result of the extraction depends on the state of the starting material to be extracted, and the determination of appropriate extraction conditions is rather complicated. However, the inventors have determined that the extraction material is relatively simple to determine from the state of the starting oil. Finding a way. In the present invention, the extraction conditions are determined so that the extraction rate satisfies certain requirements specified by the content of the polycyclic aromatic compound in the starting material oil to be extracted. Controlled by adjusting the top temperature. The requirements for the extraction rate are as follows.

That is, the starting material oil, that is, the lubricating oil fraction or de-historized oil from which extraction is performed has an aniline point of 105 to 115.
When the starting material oil has a polycyclic aromatic compound content of 0.8 to 1.5% by mass, the extraction rate is adjusted so as to satisfy the following formula (1). In the formula, Y indicates an extraction rate (%), and W indicates a polycyclic aromatic compound content (% by mass) in a starting material oil to be extracted. Here, the extraction rate is determined by setting the extraction temperature, that is, the top temperature, to about 130 ° C. or more, preferably 13 ° C.
It is adjusted by controlling in the range of 5 to 150 ° C.
As a result, the polycyclic aromatic compound concentration of the extract was 3
% By mass.

Y> 33 W + 6 (1)

[0047] In extract the aniline point obtained in this way is 80 ° C. or less, an aromatic hydrocarbon is rich,% C _A value of the ring analysis by Kurtz method is 20 to 45%. Since the extract is obtained by a solvent having an affinity for the aromatic compound, the aromatic hydrocarbon concentration of the extract does not decrease so much.

If the PCA content of the starting feed oil deviates from the above assumption in the range above the assumed range, the PCA concentration of the obtained extract exceeds 3% by mass. However, the extract can be further separated by cooling according to the first embodiment of the production method described above.Furthermore, as a result of examining the aniline point and the polycyclic aromatic compound concentration of the extract obtained in the present invention, It has been found that there is a relationship approximately represented by the following equation (2) between these. In the formula, Z indicates the aniline point (° C.), and X indicates the polycyclic aromatic compound concentration (% by mass) of the extract.

[0049]

Z = 80 / X + 38 (2) According to the formula (2), if the aniline point of the obtained extract is 80 ° C. or lower, the polycyclic aromatic compound concentration of the extract is about 1 0.9 mass% or more. When the polycyclic aromatic compound content is higher, for example, when the aniline point is 70 ° C. or lower, the concentration of the polycyclic aromatic compound becomes about 2.5% by mass or more. If the aniline point of the extract exceeds 80 ° C., the content of polycyclic aromatic compounds is unfavorable, and the product is unsuitable as a rubber processing oil.

[0050] In the conventional method, the extraction conditions are set to yield the raffinate above gel so, even on Gaité the yield of the extract at the same extraction temperature, the extract of the composition as in the present invention Hard to get. In contrast, the extract obtained in the second embodiment of the production method according to the present invention has an aniline point of 80 ° C. or lower even if the polycyclic aromatic compound content is less than 3% by mass. The reason is that the top temperature of the extraction column is 5 to 20 times lower than the conventional temperature.
It is considered that the temperature is set to be higher by ° C. That is, it is considered that when the temperature of the extraction solvent increases, the affinity of the extraction solvent for aromatic hydrocarbons other than PCA increases more than the affinity for PCA increases. Therefore,
When the extraction is performed at a higher temperature, the extraction of aromatic hydrocarbon compounds other than PCA is more improved than the extraction of PCA.

Accordingly, when the lubricating oil fraction or deasphalted oil as a starting material has an aniline point of 105 to 115 ° C. and a polycyclic aromatic compound content of 0.8 to 1.5% by mass, the overhead temperature is about 1
35 ° C. or higher, preferably 140 to 150 ° C. If the tower top temperature is lower than 135 ° C., the extract may have a polycyclic aromatic compound content of 3% by mass or more, which is not preferable. If the overhead temperature is higher than 150 ° C., it may be necessary to change the apparatus in order to adjust the pressure in the extraction column.

Even if the conditions of the starting materials or the extraction conditions are different from those described above, about 5 times less than the conventional operating conditions.
Increasing the column head temperature by ２０20 ° C. will have a similar effect in the extraction, but it may be necessary to reconsider the operating conditions and the relationship shown in equation (1).

When the second embodiment of the manufacturing method is used,
Since the extract obtained by one-stage solvent extraction can be directly used as a product, the production cost is reduced as compared with the conventional method which usually requires a dewaxing treatment after the solvent extraction.

As described above, in the first and second embodiments of the production method according to the present invention, a rubber process oil rich in aromatic hydrocarbons while having a polycyclic aromatic compound content of less than 3% by mass. Can be obtained. In this rubber process oil, the content of the polycyclic aromatic compound having three or more aromatic rings can be less than 2% by mass, which is preferable in consideration of carcinogenicity. According to the present invention, a rubber process oil having a total acid value of less than 0.04 mgKOH / g can also be obtained. Considering the durability of rubber, total acid value is 0.1mg
Since those exceeding KOH / g reduces the durability of the rubber becomes inferior thermal stability and oxidation stability, it is not preferred as a rubber process oil. Therefore, the rubber process oil obtained by the production method according to the present invention is suitable.

[0055]

The present invention and its effects will be described in more detail with reference to Examples and Comparative Examples. The measurement items in the present invention were determined according to the following methods.

[Measurement of Polycyclic Aromatic Compound (PCA) Concentration: Measurement Method by DMSO Extraction]
346 (1992 edition).

Therefore, the content of the polycyclic aromatic compound used in the present invention refers to the PCA content extracted with DMSO (dimethyl sulfoxide) according to the IP346 method, and means the polycyclic aromatic compound having three or more aromatic rings. is not.

Among PCAs, the content of polycyclic aromatic compounds having three or more aromatic rings was determined by high performance liquid chromatography (H
PLC). The measurement conditions are as follows. Column: Spherisorb A5Y 250 × 4.6 mm Oven: 40 ° C. Flow rate: 2.5 ml / min Eluent: dichloromethane / hexane Time (min) Dichloromethane (%) Hexane (%) 0.0 100 100 10.0 100 100 30.0 40 60 30.1 100 0 50.0 100 0 50.1 0 100 70.0 0 100 Detector: UV 270 nm Injection amount: 20 μl (10-fold dilution)

The content of the polycyclic aromatic compound having three or more aromatic rings in the sample is determined by the following calculation of the ratio of the compound for each number of aromatic rings in the PCA and the PCA in the sample described above.
Determined using concentration.

Ratio of monocyclic compound (%) = (area of monocyclic compound) / (area of monocyclic compound + 0.1 × area of bicyclic compound + 0.02
5 × 3 rings or more compound area) × 100 Bicyclic compound ratio (%) = (0.1 × 2 rings compound area) /
(1 ring compound area + 0.1 x 2 ring compound area + 0.025 x 3
Ring or more compound area) × 100 Ratio of three or more ring compounds (%) = (0.025 × 3 ring compound area) / (1 ring compound area + 0.1 × 2 ring compound area + 0.0
25 × 3 rings or more compound area) × 100 [Ring analysis by Kurtz method] Ring analysis value% C _A is calculated by “Fuel Analysis Test Method” (1st edition), pp. 474-478 (Nankodo, 1
968).

[Kinematic viscosity] The kinematic viscosity was measured in accordance with JIS K2283. [Aniline point] It was measured according to JIS K2256. [Total acid value] It was measured in accordance with JIS K2501.

(Example 1-1) The residue obtained by distilling Arabian light crude oil under normal pressure was distilled under reduced pressure, and the boiling point range was 340 to 65.
A distillate at 0 ° C. was collected. Next, using a rotary countercurrent contact extraction device, 2 parts by volume of furfural was added to 1 part by volume of the distillate, and solvent extraction was performed at a temperature of 115 to 120 ° C. to separate the first raffinate, A mixture of the first extract and furfural was collected. The yield of the obtained first extract with respect to the distillate oil was 40 vol% by mass. The obtained extract mixture was cooled to 60 ° C. and allowed to stand for a day and a night. A second raffinate separated from the extract was collected, and furfural contained in a small amount was distilled off to obtain a second raffinate. The yield of the second raffinate based on the first extract was 32 vol% by mass. The content of the polycyclic aromatic compound of the second raffinate measured by the IP346 method was 2.8% by mass (the content of the polycyclic aromatic compound having three or more rings was 1.8% by mass), and the value of the Kurz method ring analysis was used. % C _A is 31.5%, kinematic viscosity (40 ° C.) is 4
12 mm ² / s, aniline point 58 ° C, total acid value 0.01
mg KOH / g.

Comparative Example 1-1 As an example of a conventional rubber process oil, the content of polycyclic aromatic compounds in the first extract obtained in Example 1-1 was measured to be 23% by mass.
(The content of polycyclic aromatic compounds having three or more rings is 19.5.
% By mass). Value% C _A of Kurtz method ring analysis 48
%, Kinematic viscosity (40 ° C.) was 2360 mm ² / s, aniline point was 43 ° C., and total acid value was 0.05 mg KOH / g.

Example 1-2 A residue obtained by distilling Arabian light crude oil under reduced pressure was removed, and its kinematic viscosity (40 ° C.) was 633.
A mm ² / s de-history oil was obtained. Next, 3 parts by volume of furfural was added to 1 part by volume of the deoiling oil, and the temperature was 130 to 13.
Solvent extraction was performed at 5 ° C., and a first extract was collected. The yield of the obtained first extract with respect to the deasphalted oil was 25 vol% by mass. The obtained extract was cooled to 20 ° C. and left for one day and night.
A raffinate was collected, and furfural contained in a small amount was distilled off to obtain a second raffinate. The yield of the second raffinate based on the first extract is 73 vol% by mass.
Met. The polycyclic aromatic compound content of the second raffinate measured by the IP346 method was 1.7% by mass (3% by mass).
Ring or polycyclic aromatic compounds 1.1 wt% for content), the value% C _A of Kurtz method ring analysis of 25%, a kinematic viscosity (4
(0 ° C.) was 2940 mm ² / s, the aniline point was 67 ° C., and the total acid value was 0.01 mg KOH / g.

(Comparative Example 1-2) As a result of measuring the polycyclic aromatic compound content of the first extract obtained in Example 1-2, 5.1 mass% (polycyclic aromatic compound having three or more rings) was obtained. The content was 3.8% by mass). Value% C _A 35% of Kurtz method ring analysis, kinematic viscosity (40 ° C.) is 5740mm ² /
s, aniline point is 60 ° C, total acid value is 0.04mgKOH /
g.

(Example 2-1) A residue obtained by distilling Arabian light crude oil under normal pressure was distilled under reduced pressure, and the residue was subjected to propane elimination.
00 mm ² / s, polycyclic aromatic compound content is 1.3% by mass,
A de-historized oil having an aniline point of 109 ° C was obtained. Then, furfural 3 parts by volume added to the deasphalting oil 1 part by volume using a rotary countercurrent contact extractor performs the solvent extraction at a temperature 145 ° C., collecting a mixture of extract and Furufura Le did. The yield of the obtained extract with respect to the de-historized oil was 60 vol% by mass. The polycyclic aromatic compound content of this extract measured by the IP346 method was 2.
6 wt% (3 1.7 wt% for polycyclic aromatics content of more rings), the value% C _A of Kurtz method ring analysis of 31%,
The kinematic viscosity (40 ° C.) is 3900 mm ² / s, and the aniline point is 6
At 8 ° C., the total acid value was 0.02 mg KOH / g.

Example 2-2 The same operation as in Example 2-1 was carried out except that the extraction temperature was changed to 140 ° C. and the yield of the extract relative to the deoiled oil was set to 50% by mass. I got an event. The polycyclic aromatic compound content of this extract measured by the IP346 method was 2.9% by mass (the polycyclic aromatic compound content of three or more rings was 1.
9 wt%), the value% C _A 33% of Kurtz method ring analysis, kinematic viscosity (40 ° C.) is 4400mm ² / s, aniline point 65
° C, the total acid number was 0.02 mg KOH / g.

(Examples 2-3 and 2-4) The residue obtained by distilling Arabian light crude oil under reduced pressure was subjected to propane devastating. The kinematic viscosity (40 ° C.) was 640 mm ² / s, and the polycyclic aromatic compound content was 1.15. Mass%, aniline point is 110 ° C,
A de-historized oil having a total acid number of 0.02 mg KOH / g was obtained. next,
Add 3 parts by volume of furfural to 1 part by volume of the de-historized oil, and use a rotary countercurrent contact extraction device to obtain a temperature of 140 ° C.
Perform solvent extraction (Example 2-3) or 145 ° C. (Example 2-4) was taken a mixture of extract and Furufura Le. The yields of the obtained extract with respect to the deasphalted oil were 50 vol% by mass (Example 2-3) and 60 vol% by mass (Example 2-4). The extract of Example 2-3 had a polycyclic aromatic compound content of 2.8% by mass (1.8% by mass for a polycyclic aromatic compound content of 3 or more rings) measured by the IP346 method, and the Kurz method. Ring analysis value% C _A 31%, kinematic viscosity (40 ° C.) 4100 mm ² /
s, aniline point 66 ° C, total acid value 0.02mg KOH /
g. In Example 2-4, the content of the polycyclic aromatic compound measured by the IP346 method was 2.5% by mass (the content of the polycyclic aromatic compound having three or more rings was 1.6% by mass),
Value% C _A was 28% of the Kurtz method ring analysis, kinematic viscosity (40 ° C.)
Was 3600 mm ² / s, the aniline point was 70 ° C., and the total acid value was 0.01 mg KOH / g.

(Examples 2-5 to 2-7) The residue obtained by distilling Arabian light crude oil under reduced pressure was subjected to propane elimination, and the kinematic viscosity (40 ° C.) was 630 mm ² / s and the polycyclic aromatic compound content was 1.00. A dehistorized oil having a mass% of 110 ° C. and an aniline point was obtained. Next, 3 parts by volume of furfural is added to 1 part by volume of the deasphalted oil, and the temperature is 135 ° C. (Example 2-5) and 140 ° C. (Example 2-6) using a rotary countercurrent contact extraction device. ) or subjected to solvent extraction at 145 ° C. (example 2-7) was taken a mixture of extract and Furufura Le. The yield of the obtained extract with respect to the dehistory oil was 40 vol% (Example 2-5), 50 vol% (Example 2-6) and 60 vol% (Example 2-5), respectively.
7). The extract of Example 2-5 is IP
The polycyclic aromatic compound content measured by the 346 method is 2.
9 wt% (3 1.9 wt% for polycyclic aromatics content of more rings), the value% C _A of Kurtz method ring analysis of 32%,
Kinematic viscosity (40 ° C.) is 4200 mm ² / s, aniline point is 6
At 4 ° C., the total acid number was 0.02 mg KOH / g. In Example 2-6, the content of the polycyclic aromatic compound measured by the IP346 method was 2.4% by mass (the content of the polycyclic aromatic compound having three or more rings was 1.5% by mass), and the content was determined by the Kurz method. The value% C _A is 27% and the kinematic viscosity (40 ° C.) is 3500 mm ² /
s, aniline point 71 ° C., total acid value 0.02 mg KOH /
g. In Example 2-7, the content of the polycyclic aromatic compound measured by the IP346 method was 2.1% by mass (the content of the polycyclic aromatic compound having three or more rings was 1.3% by mass),
Value% C _A was 25% of the Kurtz method ring analysis, kinematic viscosity (40 ° C.)
Was 3100 mm ² / s, the aniline point was 78 ° C., and the total acid value was 0.01 mg KOH / g.

(Comparative Examples 2-1 to 2-3) The extraction temperature was 13
The temperature was changed to 0 ° C. (Comparative Example 2-1), 135 ° C. (Comparative Example 2-2) or 150 ° C. (Comparative Example 2-3), and the yield of the extract relative to the dehistory oil was 25% by mass (Comparative Example 2). -1), 4
0 mass% (Comparative Example 2-2) and 90 mass% (Comparative Example 2-
An extract was obtained by performing the same operation as in Example 2-1 except for 3). The extract of Comparative Example 2-1 had a polycyclic aromatic compound content of 4.8% by mass as measured by the IP346 method (a polycyclic aromatic compound content of 3 or more rings was 3.6% by mass), and the Kurz method. Ring analysis value% C _A
Was 39%, kinematic viscosity (40 ° C.) was 6,500 mm ² / s, aniline point was 55 ° C., and total acid value was 0.05 mg KOH / g. In Comparative Example 2-2, the content of the polycyclic aromatic compound measured by the IP346 method was 3.4% by mass (the content of the polycyclic aromatic compound having three or more rings was 2.5% by mass), and the content was determined by the Kurz method ring analysis. The value% C _A is 36% and the kinematic viscosity (40 ° C.) is 480.
0 mm ² / s, aniline point 61 ° C, total acid value 0.04 mg
KOH / g. In Comparative Example 2-3, the content of the polycyclic aromatic compound measured by the IP346 method was 1.8% by mass.
(The content of the polycyclic aromatic compound having three or more rings is 1.1% by mass), the value of the Kurtz method ring analysis% C _A is 18%, the kinematic viscosity (40 ° C.) is 1100 mm ² / s, and the aniline point is 81 ° C. ,
The total acid value was 0.01 mg KOH / g.

(Comparative Example 2-4) The extraction temperature was changed to 135, and the yield of the extract relative to the deoiled oil was 40% by mass.
An extract was obtained by performing the same operation as in Example 2-3, except that the above procedure was adopted. IP34 of this extract
The content of the polycyclic aromatic compound measured by Method 6 is 3.2% by mass (the content of the polycyclic aromatic compound having three or more rings is 2.
3 wt%), the value% C _A 35% of Kurtz method ring analysis, kinematic viscosity (40 ° C.) is 4900 mm ² / s, aniline point 63
° C, the total acid number was 0.03 mg KOH / g.

[0072]

As described above, the rubber processing oil obtained by the present invention has a polycyclic aromatic compound content of less than 3% by mass and a high aromatic hydrocarbon content by the IP346 method. It has excellent properties as a rubber process oil. Therefore, according to the present invention, not only a rubber process oil with little or no harm to the human body is produced,
It can be used in place of the conventional rubber process oil without greatly changing the conventional rubber manufacturing process. Furthermore,
A rubber product having no significant change in physical properties due to the treatment with the rubber process oil of the present invention can be expected, and its industrial value is extremely large.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI C10G 21/16 C10G 21/16 21/20 21/20 53/04 53/04 53/06 53/06 (56) References JP-A-56-26981 (JP, A) JP-A-56-26982 (JP, A) JP-A-12-63849 (JP, A) JP-A-11-80755 (JP, A) JP-A-11-80751 (JP, A) JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 21/00 C08C 4/00 C08L 91/00 C10G 7/06 C10G 21/00 C10G 21/16 C10G 21/20 C10G 53 / 04 C10G 53/06

Claims (13)

(57) [Claims] 1. The polycyclic aromatic compound content determined by the IP346 method is less than 3% by mass and the total acid value is 0.0
4 mgKOH / g is less than, aniline point is at 80 ° C. or less,% C _A value determined by ring analysis by Kurtz method 2
Rubber process oil that is 0-50%. 2.% C determined by ring analysis according to the Kurtz method
The rubber process oil according to claim 1, wherein the _A value is 25 to 45%. 3. The rubber process oil according to claim 1, wherein the content of the polycyclic aromatic compound having three or more rings is less than 2% by mass. 4. A feed oil selected from the group consisting of a lubricating oil fraction obtained by vacuum distillation of crude oil and a de-history oil obtained by de-historying a vacuum distillation residue of crude oil has a selective affinity for aromatic hydrocarbons. Solvent extraction step of solvent extraction with a solvent to obtain a first raffinate and a mixture of the solvent and the first extract,
A cooling step of cooling a mixture of the solvent and the first extract to separate the mixture into a second raffinate and a mixture of the second extract and the solvent;
The yield of the first extract is 55% by volume or less
The extraction temperature is 60-150 ° C.
The volume ratio of the solvent to be set in the range of 1/1 to 4/1,
In the cooling step, the yield of the second raffinate is 9
The cooling temperature is set at 10% below the extraction temperature so as to be 0 vol% or less.
A method for producing a rubber process oil, characterized in that the temperature is set in a temperature range lower by 130C . 5. A feedstock is selected from the group consisting of a deasphalted oil by deasphalting the lubricating oil fraction and crude oil vacuum distillation residue by crude oil vacuum distillation, having selective affinity for aromatic hydrocarbons a solvent extraction step of solvent extraction with a solvent, the extract that definitive in the solvent extraction process yields the following expression (1)
The extraction temperature is 140-150 ° C to satisfy
The volume ratio of the solvent to the solvent is set in the range of 1/1 to 4/1.
Method for producing a rubber process oil, characterized in that that. Y> 33W + 6 (1) (where, in the formula (1), Y is the yield of the extract (volume
%), And W is the amount of raw material oil determined by the IP method.
The content of the ring aromatic compound (% by mass) is shown. ) 6. The aniline point of the raw material oil is from 105 to 11.
6. The rubber processing oil according to claim 4 , wherein the raw material oil has a polycyclic aromatic compound content of 0.8 to 1.5 mass% as determined by the IP346 method at 5 ° C. 7. Production method. 7. A feedstock is selected from the group consisting of a deasphalted oil by deasphalting the vacuum distillation residue of the lubricating oil fraction and oil from oil vacuum distillation, having selective affinity for aromatic hydrocarbons Solvent extraction step of solvent extraction with a solvent to obtain a first raffinate and a mixture of the solvent and the first extract,
It separated a mixture of said container agent and the first second raffinate to cool the mixture of extract and the second extract and the solvent have a cooling step of obtaining the second raffinate, the solvent yield In the dispensing process, the first extra
The extraction temperature is set to 60 so that the yield of
~ 150 ° C, the volume ratio of the solvent to the feed oil is 1/1
４4/1 and set in the cooling step.
2 Cool to reduce the raffinate yield to 90% by volume or less.
Set the cooling temperature in a temperature range 10 to 130 ° C lower than the extraction temperature.
A process for producing a rubber process oil. 8. When the polycyclic aromatic compound content of the first extract is 20 to 30% by mass, the mixture of the solvent and the first extract is cooled to 10 to 110 ° C. in the cooling step by an extraction temperature. When cooled at a low temperature, the second raffinate is obtained in a yield of 50% by volume or less based on the first extract, and when the polycyclic aromatic compound content of the first extract is 3 to 10% by mass, In a cooling step, the mixture of the solvent and the first extract is cooled at a temperature 20 to 130 ° C. lower than the extraction temperature, and the second extract is produced in a yield of 50 to 90% by volume based on the first extract. The method for producing a rubber processing oil according to claim 4 or 7, wherein a raffinate is obtained. 9. A feedstock is selected from the group consisting of a deasphalted oil by deasphalting the vacuum distillation residue of the lubricating oil fraction and oil from oil vacuum distillation, having selective affinity for aromatic hydrocarbons and solvent extraction at 140 ° C. or more extraction temperature in a solvent comprising a step of separating into a raffinate and extract, soluble as the yield of the extract satisfies the following formula (1)
A method for producing a rubber process oil, comprising setting an amount of an agent and an extraction temperature . Y> 33W + 6 (1) (wherein, in the formula (1), Y is the yield of the extract ( volume)
% ), And W represents the content (% by mass) of the polycyclic aromatic compound in the feedstock oil determined by the IP method. ) 10. The method for producing a rubber process oil according to claim 9, wherein a volume ratio of the solvent to the stock oil in the solvent extraction is from 1/1 to 4/1. Wherein said extraction solvent is furfural, phenol and the method of manufacturing a rubber process oil according to any one of claims 4 to 10, characterized in that it is selected from the group consisting of N- methyl-2-pyrrolidone . 12. The production method according to claim 4, 7 and 8.
The second raffinate in the above, or the claims 5, 6, 9 and
Extra in the production method according to any one of claims 10 and 10.
And the number determined by the IP346 method
The content of a ring aromatic compound is less than 3% by mass,
Is below 80 ° C and determined by ring analysis by Kurtz method
% C _A A rubber process oil having a value of 20-50%. 13. Polycyclic as determined by the IP346 method
13. The aromatic compound content is 1.9% by mass or more.
The rubber process oil described .