JPH0586993B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for producing a highly aromatic-containing oil, and in particular to a method for producing an extract by-produced in a lubricating oil refining process as a lubricating oil or a solvent. [Prior Art] Lubricating oils or high boiling point solvents that have high fluidity and good solubility at low temperatures have conventionally been
Naphthenic base oil obtained from naphthenic crude oil or synthetic oil is used. However, the production of the above-mentioned naphthenic crude oil is decreasing worldwide, and it is becoming difficult to obtain it.
On the other hand, the latter synthetic oil has the disadvantage of being expensive. In view of the current situation, the present applicant proposes to solvent-extract the lubricating oil fraction etc. obtained from paraffin base crude oil or mixed base crude oil, and to obtain roughinate by re-solvent extracting or cooling the extract, and to utilize this extract. proposed a method (Special Publication No. 61-21510,
Publication No. 61-21511). [Problems to be solved by the invention] Roughinate obtained by the above method is rich in aromatic components and has excellent fluidity or solubility at low temperatures, but it is somewhat lacking in stability and requires post-treatment such as clay treatment. It requires a process and is colored, which limits its use as a solvent.
Furthermore, the roughinate obtained by the above method has problems such as a low yield and high manufacturing cost. The present invention has solved this problem, and an object of the present invention is to produce a large amount of highly aromatic-containing oil that has excellent fluidity and solubility at low temperatures, good stability, and almost no coloration. The purpose is to provide an efficient manufacturing method. [Means for Solving the Problems] The present invention as a means for solving the above-mentioned problems is based on the aromatic This method consists of adding an aqueous alkali solution or an organic alkaline solution to an extract extracted with a solvent that has a selective affinity for hydrocarbons, and bringing the mixture into contact with the extract. In the present invention, the lubricating oil fraction extracted from the above-mentioned crude oil is preferably extracted from paraffin base crude oil or mixed base crude oil, and is obtained by distilling the atmospheric distillation residue of these crude oils under reduced pressure, for example, in terms of atmospheric pressure. Boiling point about 250 to about 400℃, boiling point about 350 to 500℃, and about 450℃
Fractions between about 650° C. and about 650° C. are preferred. Further, the above-mentioned deasphalted oil refers to deasphalted oil obtained by deasphalting the above-mentioned atmospheric distillation residue or vacuum distillation residue using propane or the like. These lubricating oil fractions and deasphalted oils may be used as they are, or may be subjected to hydrogenation treatment or
Alternatively, it may be one that has been subjected to a dewaxing treatment or the like. Hydrogenation treatment in this case is carried out in ordinary refining of lubricating oils, such as Ni, Co, Mo, W,
Using a catalyst in which about 0.1 to about 10% by weight of one or more of Ti, V, etc. is supported on a carrier such as silica, alumina, silica-alumina, etc., the hydrogen pressure is about 30 to 150 kg/
cm ² (G), temperature approximately 300 to 450℃, liquid space velocity 0.2 to
An example is a method in which the sulfur content is brought into contact with the raw material oil for 5 hr ^-1 and the sulfur content is 1% by weight or less, preferably 0.5% by weight or less. Further, the above-mentioned dewaxing treatment is also carried out in the usual refining of lubricating oil, and may be either solvent dewaxing or hydrogen dewaxing. For solvent dewaxing, mix acetone or a mixed solvent of methyl ethyl ketone/toluene with the above hydrogenated oil or hydrogenated ruffinate oil to a volume of 2/1 to 3/1.
An example is a method of cooling to a temperature of -30°C, filtering the precipitated wax, and separating it from the oil.
Hydrodewaxing treatment is a method of selectively decomposing and removing only the wax component in a hydrogenation atmosphere using a catalyst such as synthetic zeolite. These hydrogenation treatments or dewaxing treatments may be performed alone or both may be performed in parallel, or either treatment may be performed first. In particular, if lubricating oil fractions and deasphalted oils are subjected to the above-mentioned hydrogenation treatment and then dewaxed, the pour point will be significantly lowered, and together with their high solubility, they will be used as refrigeration oils and electrical appliances for cold regions. You can obtain something suitable for insulating oil, etc. In the present invention, the lubricating oil fraction or deasphalted oil treated or not treated by the above method is treated with a solvent having selective affinity for aromatic hydrocarbons, that is,
Extraction treatment is performed using a solvent that has the effect of selectively extracting aromatic carbon. Examples of this solvent include furfural, phenol, N-methylpyrrolidone, etc., and these can be used alone or in combination of two or more. In this solvent extraction process, the lubricating oil fraction or deasphalted oil and the solvent are
At 120℃ temperature, the volume ratio of solvent/oil is 1/1~3/
It is better to make contact as 1. The solvent is recovered from the extract portion obtained by this contact to obtain an extract. This extract is
Yield 5-30% by volume, preferably 5-25% by volume
It is preferable to make it so that An aqueous alkaline solution or an organic alkaline solution is added to the extract thus obtained.
Examples of the alkaline aqueous solution in this case include an aqueous solution of sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, etc. with a concentration of 0.5 to 10% by weight. On the other hand, organic alkaline solutions include alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol, and isopropyl alcohol, or alkali-soluble solvents such as acetone and glycerin, and sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, etc. 0.5 alkali
An example is one dissolved at a concentration of ~10% by weight. The amount of these solutions to be added to the oil is determined by taking into account the concentration of the solution, the treatment history of the oil, etc., but generally it is preferably selected as appropriate within the range of 0.05 to 100% by volume relative to the oil. After addition of the above solution, in the case of an aqueous solution, it is preferable to stir and mix thoroughly. In this case, room temperature may be used, but a higher temperature is preferable because the viscosity decreases and mixing and contacting becomes easier. The aqueous layer is then separated. This significantly improves hue, acid value, etc. Furthermore, if distillation is performed after addition of the above solution, the hue, acid value, etc. will be further significantly improved, making it suitable for use where higher quality is required. At this time, when an aqueous solution is added, it is preferable to separate the aqueous layer and then distill it. However, when a small amount of the aqueous solution is added, distillation may be performed as it is without layer separation. If it is not separated, water or a solution will be distilled out first and should be collected and removed. It is preferable to perform distillation under reduced pressure in order to prevent decomposition, deterioration, etc. of the oil and increase the recovery rate. The degree of reduced pressure, distillation temperature, etc. are appropriately selected depending on the type of oil and the purpose of use of the treated oil. It goes without saying that the high aromatic content oil obtained by the above method may be further subjected to neutralization with an aqueous acid solution such as sulfuric acid, clay treatment, etc., depending on the purpose of use. This high aromatic content oil can be used as a refrigerating machine oil, an electrical insulating oil, an extender for rubber, especially white rubber, and a solvent for hardly soluble additives such as a cetane number improver and an antifoaming agent. [Examples] Example 1 The residual oil obtained by distilling paraffin crude oil at atmospheric pressure was distilled under reduced pressure to obtain a distillate having a boiling point of 250 to 400°C in terms of atmospheric pressure. Using a Co-Mo hydrogenation catalyst,
The sulfur content was reduced by hydrogenation under the conditions of hydrogen pressure 100Kgf/cm ² (G), temperature 360-370℃, and liquid hourly space velocity 1.0hr ^-1 .
0.1 hydrogenated oil was obtained. Using a rotating plate type countercurrent contact extraction device, 180% by volume of furfural was added to the above hydrogenated oil.
Contact and extraction was carried out at a temperature of 45°C. Furfural was removed from the obtained extract portion to obtain an extract. A 3° Baume aqueous sodium hydroxide solution was added to this extract and mixed with stirring. After standing still, the layers were separated and properties were measured. The conditions for addition and mixing in this case are shown in Table 1, and the properties of the oil after layer separation are shown in Table 2. Next, the liquid after layer separation was distilled under a reduced pressure of 2 mmHg, and a 90% distillate was collected from the first distillation of the vacuum distillation, and the properties of this fraction were measured, and the results are shown in Table 2. . The extract and the 90% distillate from the first distillation obtained by similarly distilling it under reduced pressure without adding an aqueous sodium hydroxide solution were also measured, and the results are also listed in Table 2.

[Table] As is clear from the results in Table 2, the oil obtained by the method of the present invention has significantly improved hue and acid value, has a high aromatic content, and is an oil that can be used as an extender for white rubber. It can be seen that it is suitable as a solvent for poorly soluble additives such as additives, cetane number improvers, and antifoaming agents.

[Table] Example 2 To the extract obtained in the same manner as in Example 1, 0.1% by volume of a solution of 5.5g of sodium hydroxide dissolved in 100ml of isopropyl alcohol was added,
It was distilled under reduced pressure at 4 mmHg. 70 from the first distillation of this distillation
% fraction was obtained and the properties were measured, and the results were as shown in Table 3.

[Table] As is clear from the results, the oil obtained by the method of the present invention has excellent hue and thermal stability,
It is also a high aromatic content oil and an extender for white rubber.
It can be seen that it is suitable as a solvent for poorly soluble additives such as cetane number improvers and antifoaming agents. Example 3 The residual oil obtained by distilling paraffin crude oil at atmospheric pressure was distilled under reduced pressure to obtain a distillate having a boiling point of 250 to 400°C in terms of atmospheric pressure. Using a rotating plate type countercurrent contact extraction device, this was extracted with 180% by volume of furfural based on the above distillate oil, and 45%
Contact and extraction was carried out at a temperature of °C. Furfural was removed from the obtained extract portion to obtain an extract. A 3° Baume aqueous sodium hydroxide solution was added to this extract in an amount of 3% by volume based on the extract, and the mixture was stirred and mixed at a temperature of 85° C. for 30 minutes. After standing still, the layers were separated and distilled under reduced pressure to 2 mmHg. A 90% distillate was collected from the first distillation of the vacuum distillation, and the properties of this fraction were measured. The results are shown in Table 4. In addition, the extract and the 90% distillate from the first distillation obtained by similarly distilling under reduced pressure without adding an aqueous sodium hydroxide solution were also measured, and the results are also listed in Table 4.

【table】

[Table] The oil obtained by the method of the present invention has significantly improved hue and acid value, and has a high aromatic content. It can be seen that it is suitable as a solvent for soluble additives. Example 4 To the hydrogenated oil obtained by the same method as described in Example 1, 2 parts by volume of a mixed solvent of toluene/methyl ethyl ketone (50/50 volume ratio) was added to 1 part by volume of the oil, and the mixture was heated at -30°C. The precipitated wax was filtered to obtain a dewaxed oil. This dewaxed oil had a pour point of -27.5°C. Next, using a rotating plate type countercurrent contact extraction device, 180% by volume of furfural was added to the above dewaxed oil, and
Contact and extraction was carried out at a temperature of °C. Furfural was removed from the obtained extract portion to obtain an extract. A 3° Baume aqueous sodium hydroxide solution was added to this extract, mixed with stirring, allowed to stand, separated into layers, and distilled under reduced pressure to 2 mmHg. A 90% distillate was collected from the first distillation of vacuum distillation and its properties were measured. The results are shown in Table 5. In addition, the properties of the 90% distillate from the first distillation, which was similarly distilled under reduced pressure without adding an aqueous sodium hydroxide solution, were also measured.
The results are also listed in Table 5.

[Table] As is clear from this result, the oil of the present invention has
It has extremely low pour point, hue, and acid value, and is rich in aromatics, making it suitable as a refrigeration oil or electrical insulating oil for cold regions. [Effects of the Invention] Since the extract is treated with an aqueous alkaline solution or an organic alkaline solution, the present invention has excellent fluidity and solubility at low temperatures, good stability, and almost no coloration, and is suitable for use in refrigeration oil, electricity, etc. It is said that it is possible to efficiently produce large quantities of highly aromatic-containing oils that can be used as insulating oils, rubber extenders, especially white rubber extenders, and solvents for poorly soluble additives such as cetane number improvers and antifoaming agents. be effective.

Claims (1)

[Scope of Claims] 1. Extra extracted from a lubricating oil fraction collected from crude oil or deasphalted oil obtained by deasphalting the distillation residue of crude oil with a solvent that has a selective affinity for aromatic hydrocarbons. 1. A method for producing a highly aromatic-containing oil, which comprises treating oil with an aqueous alkaline solution or an organic alkaline solution. 2. The method for producing a highly aromatic-containing oil according to claim 1, wherein the treatment with an aqueous alkali solution involves phase separation after mixing and contact with the aqueous alkali solution. 3. The method for producing a highly aromatic-containing oil according to claim 1, wherein the treatment with an aqueous alkaline solution or an organic alkaline solution involves distillation separation after mixing and contact with the solution. 4. The highly aromatic-containing oil according to claim 1, wherein the lubricating oil fraction or deasphalted oil has been previously subjected to hydrogenation treatment, dewaxing treatment, or both. Production method. 5 The solvent having selective affinity for aromatic hydrocarbons is furfural, phenol, or N
2. The method for producing a highly aromatic-containing oil according to claim 1, wherein the oil is selected from -methylpyrrolidone or a mixture of two or more thereof.