JP2001164268A - New dewaxing auxiliary - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a dewaxing auxiliary effective for all the wax-containing hydrocarbon oils (especially heavy oil) in a method for dewaxing a solvent using a dewaxing auxiliary, SOLUTION: In a process for dewaxing a solvent of wax-containing hydrocarbon oil, a mixture of three kinds of a polyalkyl methacrylate having a 10-22C alkyl chain length and 10,000-800,000 average molecular weight, a polyalkyl (meth)acrylate having a 18-30C alkyl chain length and 10,000-800,000 average molecular weight and a polyalkylated naphthalene condensate having 1,000-100,000 average molecular weight is used as the dewaxing auxiliary.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solvent dewaxing method using a dewaxing aid, and in particular, in a dewaxing step, a wax-containing hydrocarbon oil and a dewaxing aid are dissolved in a dewaxing solvent and cooled. The present invention relates to a solvent dewaxing method in which wax present in wax-containing hydrocarbon oil is precipitated, and the precipitated wax is separated by a liquid / solid separation method to produce a dewaxed oil.

[0002]

2. Description of the Related Art In general, in order to produce hydrocarbon oil from crude oil, first, crude oil is distilled under normal pressure, and the residual oil is further distilled under reduced pressure to obtain various wax-containing hydrocarbon oils having low to high viscosity. Separate into vacuum distillation bottoms. By further removing the solvent from the vacuum distillation residue and removing the asphalt component, it is possible to produce a bright stock wax-containing hydrocarbon oil having the highest viscosity. The wax-containing hydrocarbon oils of various viscosities thus obtained are subjected to solvent extraction,
A combination of hydrorefining and dewaxing, or hydrocracking,
It is subjected to a series of processing steps such as a combination of solvent extraction, hydrorefining and dewaxing, and becomes a hydrocarbon oil. The dewaxing step of the above production steps refers to a step of removing wax components in the waxy hydrocarbon oil to produce a low pour point hydrocarbon oil.

[0003] When the dewaxing step is carried out industrially, there is a case where press filtration is performed on the way. In this case, the wax-containing hydrocarbon oil is cooled in the absence of a solvent to precipitate wax, which is press-filtered. Generally, in a dewaxing method including a press filtration step, only a light-type wax-containing hydrocarbon oil can be treated due to a limitation due to viscosity. Therefore, in general, a solvent dewaxing method capable of performing a light-based or heavy-based treatment is used. In the solvent dewaxing method, a wax-containing hydrocarbon oil, a dewaxing solvent and a dewaxing aid are dissolved and wax is precipitated while cooling to form a slurry. This slurry is supplied to a solid / liquid separator (filtration, centrifugation, etc.), and after separation, the dewaxing solvent is removed to obtain a dewaxed oil.

[0004] Dewaxing solvents used in the solvent dewaxing method include hydrocarbons (propane, propylene, butane, pentane, etc.) and ketones (acetone, methyl ethyl ketone (ME
K), methyl isobutyl ketone (MIBK) and mixtures thereof), aromatic hydrocarbons (benzene, toluene, xylene), and mixtures of ketones and aromatic hydrocarbons (MEK)
/ Toluene and acetone / benzene).

[0005] A factor that limits the throughput in the solvent dewaxing process is the rate of wax filtration from the slurry, which is affected by the crystal structure of the deposited wax. The crystal structure of the deposited wax is affected by the operating conditions in the dewaxing step. In particular, due to changes in the cooling speed, stirring speed, cooling temperature, and other conditions, even the same wax-containing hydrocarbon oil significantly changes the size, crystal structure, and state of the oil in the crystal of the precipitated wax, and the filtration speed and the yield of dewaxed oil. Affects rate. Especially when the wax-containing hydrocarbon oil is bright stock, the wax crystals are fine, so the filtration speed is reduced, the yield of the dewaxed oil is reduced, the pour point of the dewaxed oil is increased due to the passage of the fine crystals, and the filter is removed. Troubles such as clogging often occur, and these solutions have been eagerly desired. Although various processes have been improved to improve the filtration rate and the yield of dewaxed oil, a method of adding a dewaxing aid to a method which is easy and has a large effect has been implemented. In particular, in a self-cooling type dewaxing method such as propane dewaxing, it has been essential to add a dewaxing aid.

The following techniques have heretofore been known as dewaxing aids. JP-B-45-15379, JP-B-49-26922, and JP-A-54-11104 describe the effects of using a mixture of polyethylene vinyl acetate and polyalkyl acrylate or polyalkyl methacrylate. JP-A-45-15379, JP-B-49-46361, and JP-A-53-129202 describe the effects of using a polyalkylnaphthalene condensate or a mixture with a polyalkylmethacrylate. JP-A-53-121804, JP-A-53-1
21803 describes the effect of using an α-olefin polymer or a copolymer with vinyl acetate.
JP-A-S40-4210, JP-A-54-123102, JP-A-57-30792, and JP-A-7-316567 include:
The effect of using a polyalkyl acrylate is described. JP-A-55-89392 describes the effect of using polyvinylpyrrolidone. JP-A-60-2
17218 and JP-A-61-247793 describe the effect of using a copolymer of dialkyl fumarate and vinyl acetate. JP-B-7-116454 has an alkyl chain length of 10 to 26 carbon atoms and a number average molecular weight of 3,0.
It describes the use of a polyalkyl methacrylate having a number average molecular weight of 5,000 to 20,000 having an alkyl chain length of 10 to 20 carbon atoms having a polyalkyl methacrylate of 100 to 500,000, and a mixing ratio of these. 1 /
6 to 2/1, but 50% or more of the alkyl group portion of the polyalkyl acrylate has 16 or more carbon atoms.
As described above, when the mixing amount of the polyalkyl acrylate is relatively large as described above, the pour point of the product becomes high and handling becomes difficult. In addition, propane dewaxing did not provide a sufficient effect.

However, among these, as dewaxing aids which are currently used, there are polyalkyl methacrylate, polyalkyl acrylate, polyethylene vinyl acetate and polyalkylnaphthalene condensates. However, these dewaxing aids cannot be said to have a sufficient effect on all waxy hydrocarbon oils from light to bright stock.

[0008]

The problem to be solved by the present invention is that the wax-containing hydrocarbon oils such as bright stock, which are currently used as dewaxing assistants, often cause clogging and other troubles. The filtration speed and the yield of the dewaxed oil are reduced, and the dewaxing efficiency cannot be said to be sufficiently improved. Therefore, in a solvent dewaxing method using a dewaxing aid, a dewaxing aid effective for any wax-containing hydrocarbon oil such as a heavy type or a bright stock as well as a light type, that is, a filtration rate, The purpose is to search for a dewaxing aid that improves the dewaxing oil yield.

[0009]

Means for Solving the Problems The present inventors have made intensive studies to solve these problems, and have reached the present invention. That is, by mixing polyalkyl methacrylate, polyalkyl (meth) acrylate and polyalkylated naphthalene condensate, it is possible to increase the filtration rate particularly for waxy hydrocarbon oils having relatively many troubles such as heavy oil and bright stock. It is based on the discovery that it can be obtained as a dewaxing aid having greatly improved and excellent performance.

There are various dewaxing methods,
Solvent dewaxing methods useful in the use of the dewaxing aid according to the present invention are those using gaseous hydrocarbons (propane, propylene, butane, butene) at room temperature.
The dewaxing aid used at this time is a compound (A) shown below.
Having an alkyl chain length of 10 to 20 carbon atoms and an average molecular weight of 1
Polyalkyl methacrylate of 000 to 800,000, (B) polyalkyl (meth) acrylate having an alkyl chain length of 18 to 30 carbon atoms and having an average molecular weight of 10,000 to 800,000, and (C) average molecular weight 1,00
0 to 100,000 polyalkylated naphthalene condensates, and these three kinds of compounds were obtained by A / B = 200/1 to
A + B / C = 10/1 to 9/1 (weight ratio)
/ 10, which means that they are added to the wax-containing hydrocarbon oil in the range of 0.01 to 1.00 mass%.

That is, the present invention relates to a wax-containing hydrocarbon containing three kinds of mixtures of polyalkyl methacrylate, polyalkyl (meth) acrylate and polyalkylated naphthalene condensate having an average molecular weight and a carbon number of an alkyl group within a specific range. It is characterized in that it is used as a dewaxing aid in an oil dewaxing step.

There are various methods for obtaining the product of the present invention. As a method for obtaining polyalkyl methacrylate (A) and polyalkyl (meth) acrylate (B), for example, each monomer and a reaction solvent are added to a reaction apparatus, and after nitrogen replacement, heating is performed, and a generally used starting method is used. By adding the agent, polymerization is performed to obtain each polymer.

The polyalkylated naphthalene condensate (C) can be obtained, for example, by adding naphthalene to chlorinated paraffin, dissolving it by heating, and adding aluminum chloride as a catalyst thereto to cause a reaction.

These three types are used by adjusting the concentration of 10 to 80% with mineral oil or the like for easy handling, and changing the mixing ratio of the three types.

The method for adding the dewaxing aid according to the present invention is as follows.
There is no particular limitation as long as it is uniformly dissolved in the waxy hydrocarbon oil before cooling, and it is also preferable to dissolve it in a dewaxing solvent in advance in terms of working efficiency. The dewaxing aid according to the present invention may contain other components as long as the effects of the present invention are not impaired.

[0016]

DETAILED DESCRIPTION OF THE INVENTION A wax-containing hydrocarbon oil is dissolved in a dewaxing solvent, a dewaxing aid comprising components (A), (B) and (C) is added, and the mixture is made uniform and heated. Next, the mixture is cooled to a predetermined temperature. In this cooling, a slurry composed of precipitated wax, dewaxing oil, dewaxing solvent, and dewaxing aid is produced, and then the slurry is filtered to separate wax to remove the dewaxing solvent. To obtain a dewaxed oil.
At this time, the filtration speed and the yield of the dewaxed oil were measured to evaluate the performance of the dewaxing aid.

[0017]

EXAMPLES The present invention will be described below with reference to synthesis examples, test methods, and examples, but the present invention is not limited to these synthesis examples, test methods, and examples.

Synthesis Example 1 C12 to C18 (C12 = 24%, C14 = 23%,
(C16 = 27%, C18 = 25%) alkyl methacrylate and a reaction solvent are charged into a reaction vessel and sufficiently substituted with nitrogen. Thereafter, a commonly used initiator is added and the temperature is raised, and then 10 hours. By aging, polyalkyl methacrylate (A) having an average molecular weight of 450,000 was obtained.

Synthesis Example 2 18 to 22 carbon atoms (C18 = 43%, C20 = 11%,
(C22 = 44%) alkyl acrylate and a reaction solvent are charged into a reaction vessel and sufficiently purged with nitrogen. Then, a commonly used initiator is added to the mixture to raise the temperature, followed by aging for 8 hours to obtain an average molecular weight. 400,000 polyalkyl acrylates (B) were obtained.

Synthesis Example 3 Chlorinated paraffin and naphthalene are charged into a reaction vessel, heated at 60 to 65 ° C., and anhydrous chlorinated aluminum as a catalyst is continuously dropped therein for 30 minutes. Several minutes after the addition, hydrochloric acid gas is generated vigorously to react. Five hours after the catalyst was dropped, steam was introduced to decompose the catalyst. Toluene is added and the mixture is washed well with 5% aqueous hydrochloric acid, warm water, and 1% aqueous sodium hydrogen carbonate until aluminum ions are eliminated. The remaining water is removed by boiling with toluene and removed to make it anhydrous. At this time, since it contains some organic chlorine, 0.5% of alkylethylenediamine is added, and the mixture is reacted for 2 hours while refluxing at the boiling point of toluene. Thereafter, the mixture was cooled and washed with water until it became neutral, and toluene was distilled off to obtain a polyalkylated naphthalene condensate (C) having an average molecular weight of 40,000.

Synthesis Example 4 C12 to C15 (C12 = 20%, C13 = 31%,
(C14 = 33%, C15 = 16%) Alkyl acrylate and the reaction solvent are charged into the reaction vessel and sufficiently purged with nitrogen. Then, a commonly used initiator is added, the temperature is raised, and then aging is performed for 10 hours. As a result, a polyalkyl acrylate (D) having an average molecular weight of 400,000 was obtained.

Test Method [0022] Wax-containing hydrocarbon oil (light, heavy, bright stock) was converted to normal hexane (4% to wax-containing hydrocarbon oil).
) At 50 ° C to dissolve it, add the dewaxing aid synthesized above to it, and stir at a cooling rate of 2 ° C / min.
It was cooled to 40 ° C. Then, using a filter cloth using a slurry composed of wax, normal hexane, dewaxing oil, and a dewaxing aid in a real machine, vacuum filtration was performed at 600 mmHg, and the speed when the volume became 50 ml was obtained.
The obtained filtrate and, after filtration, normal hexane contained in each of the waxes were removed by an evaporator, and the yield was determined from the weight.

Example 1 1.0 g of (A) obtained in Synthesis Example 1, 0.1 g of (B) obtained in Synthesis Example 2, and 2.0 g of (C) obtained in Synthesis Example 3
Were mixed, and 0.5 g of these three kinds of mixtures and 200 g of a light wax-containing hydrocarbon oil were tested in accordance with the test method.

Example 2 1.0 g of (A) obtained in Synthesis Example 1, 0.1 g of (B) obtained in Synthesis Example 2, and 2.0 g of (C) obtained in Synthesis Example 3
Were tested, and 0.2 g of these three kinds of mixtures and 200 g of a light wax-containing hydrocarbon oil were tested according to the test method.

Example 3 1.0 g of (A) obtained in Synthesis Example 1, 0.05 g of (B) obtained in Synthesis Example 2, and 1.0 g of (C) obtained in Synthesis Example 3
g of the mixture, and 0.5 g of these three kinds of mixtures and 200 g of a light wax-containing hydrocarbon oil were tested according to the test method.

Example 4 1.0 g of (A) obtained in Synthesis Example 1, 0.05 g of (B) obtained in Synthesis Example 2, and 1.0 g of (C) obtained in Synthesis Example 3
g was mixed, and 0.2 g of these three kinds of mixtures and 200 g of a light wax-containing hydrocarbon oil were tested according to the test method.

COMPARATIVE EXAMPLE 1 Light wax-containing hydrocarbon oil 20 without adding a dewaxing aid
The test was performed according to the test method using only 0 g.

Comparative Example 2 1.0 g of (A) obtained in Synthesis Example 1, 0.1 g of (D) obtained in Synthesis Example 4, and 2.0 g of (C) obtained in Synthesis Example 3
Were mixed, and 0.5 g of these three kinds of mixtures and 200 g of a light wax-containing hydrocarbon oil were tested in accordance with the test method.

Comparative Example 3 1.0 g of (A) obtained in Synthesis Example 1, 0.1 g of (D) obtained in Synthesis Example 4, and 2.0 g of (C) obtained in Synthesis Example 3
Were tested, and 0.2 g of these three kinds of mixtures and 200 g of a light wax-containing hydrocarbon oil were tested according to the test method.

COMPARATIVE EXAMPLE 4 4.0 g of (A) obtained in Synthesis Example 1 and 1.0 g of (B) obtained in Synthesis Example 4 were mixed, and 0.5 g of a mixture of the two was obtained.
A test was conducted on 200 g of a light wax-containing hydrocarbon oil according to the test method.

COMPARATIVE EXAMPLE 5 4.0 g of (A) obtained in Synthesis Example 1 and 1.0 g of (B) obtained in Synthesis Example 4 were mixed, and 0.2 g of these two kinds of mixtures were mixed.
A test was conducted on 200 g of a light wax-containing hydrocarbon oil according to the test method.

Table 1 shows the dewaxing performance of the light wax-containing hydrocarbon oils obtained in Examples 1 to 4 and Comparative Examples 1 to 5.

[0033]

[Table 1]

Example 5 1.0 g of (A) obtained in Synthesis Example 1, 0.1 g of (B) obtained in Synthesis Example 2, and 2.0 g of (C) obtained in Synthesis Example 3
Were mixed, and 0.5 g of these three kinds of mixtures and 200 g of heavy wax-containing hydrocarbon oil were tested in accordance with the test method.

Example 6 1.0 g of (A) obtained in Synthesis Example 1, 0.1 g of (B) obtained in Synthesis Example 2, and 2.0 g of (C) obtained in Synthesis Example 3
Were tested, and 0.2 g of these three kinds of mixtures and 200 g of heavy wax-containing hydrocarbon oils were tested according to the test method.

Example 7 1.0 g of (A) obtained in Synthesis Example 1, 0.05 g of (B) obtained in Synthesis Example 2, and 1.0 g of (C) obtained in Synthesis Example 3
g, and 0.5 g of these three types of mixtures and 200 g of heavy wax-containing hydrocarbon oil were tested according to the test method.

Example 8 1.0 g of (A) obtained in Synthesis Example 1, 0.05 g of (B) obtained in Synthesis Example 2, and 1.0 g of (C) obtained in Synthesis Example 3
g was mixed, and 0.2 g of these three kinds of mixtures and 200 g of heavy wax-containing hydrocarbon oil were tested in accordance with the test method.

Comparative Example 6 Heavy wax-containing hydrocarbon oil 20 without adding a dewaxing aid
The test was performed according to the test method using only 0 g.

Comparative Example 7 1.0 g of (A) obtained in Synthesis Example 1, 0.1 g of (D) obtained in Synthesis Example 4, and 2.0 g of (C) obtained in Synthesis Example 3
Were mixed, and 0.5 g of these three kinds of mixtures and 200 g of heavy wax-containing hydrocarbon oil were tested in accordance with the test method.

Comparative Example 8 1.0 g of (A) obtained in Synthesis Example 1, 0.1 g of (D) obtained in Synthesis Example 4, and 2.0 g of (C) obtained in Synthesis Example 3
Were tested, and 0.2 g of these three kinds of mixtures and 200 g of heavy wax-containing hydrocarbon oils were tested according to the test method.

COMPARATIVE EXAMPLE 9 4.0 g of (A) obtained in Synthesis Example 1 and 1.0 g of (B) obtained in Synthesis Example 4 were mixed, and 0.5 g of a mixture of the two was obtained.
200 g of heavy wax-containing hydrocarbon oil was tested according to the test method.

COMPARATIVE EXAMPLE 10 4.0 g of (A) obtained in Synthesis Example 1 and 1.0 g of (B) obtained in Synthesis Example 4 were mixed, and 0.2 g of these two kinds of mixtures were mixed.
200 g of heavy wax-containing hydrocarbon oil was tested according to the test method.

Table 2 shows the dewaxing performance for the heavy wax-containing hydrocarbon oils obtained in Examples 5 to 8 and Comparative Examples 6 to 10.

[0044]

[Table 2]

Example 9 1.0 g of (A) obtained in Synthesis Example 1, 0.1 g of (B) obtained in Synthesis Example 2, and 2.0 g of (C) obtained in Synthesis Example 3
Were mixed, and 0.5 g of these three kinds of mixtures and 200 g of bright stock wax-containing hydrocarbon oil were tested in accordance with the test method.

Example 10 1.0 g of (A) obtained in Synthesis Example 1, 0.1 g of (B) obtained in Synthesis Example 2, and 2.0 g of (C) obtained in Synthesis Example 3
Were mixed, and 0.2 g of these three kinds of mixtures and 200 g of bright stock wax-containing hydrocarbon oil were tested according to the test method.

Example 11 1.0 g of (A) obtained in Synthesis Example 1, 0.05 g of (B) obtained in Synthesis Example 2, and 1.0 g of (C) obtained in Synthesis Example 3
g was mixed, and 0.5 g of these three kinds of mixtures and 200 g of bright stock wax-containing hydrocarbon oil were tested according to the test method.

Example 12 1.0 g of (A) obtained in Synthesis Example 1, 0.05 g of (B) obtained in Synthesis Example 2, and 1.0 g of (C) obtained in Synthesis Example 3.
g was mixed, and 0.2 g of these three kinds of mixtures and 200 g of bright stock wax-containing hydrocarbon oil were tested according to the test method.

Comparative Example 11 A test was conducted according to the test method using only 200 g of bright stock wax-containing hydrocarbon oil without adding a dewaxing aid.

Comparative Example 12 1.0 g of (A) obtained in Synthesis Example 1, 0.1 g of (D) obtained in Synthesis Example 4, and 2.0 g of (C) obtained in Synthesis Example 3
Were mixed, and 0.5 g of these three kinds of mixtures and 200 g of bright stock wax-containing hydrocarbon oil were tested in accordance with the test method.

Comparative Example 13 1.0 g of (A) obtained in Synthesis Example 1, 0.1 g of (D) obtained in Synthesis Example 4, and 2.0 g of (C) obtained in Synthesis Example 3
Were mixed, and 0.2 g of these three kinds of mixtures and 200 g of bright stock wax-containing hydrocarbon oil were tested according to the test method.

Comparative Example 14 4.0 g of (A) obtained in Synthesis Example 1 and 1.0 g of (B) obtained in Synthesis Example 4 were mixed, and 0.5 g of a mixture of the two was obtained.
200 g of bright stock wax-containing hydrocarbon oil was tested according to the test method.

Comparative Example 15 4.0 g of (A) obtained in Synthetic Example 1 and 1.0 g of (B) obtained in Synthetic Example 4 were mixed, and 0.2 g of the mixture of the two was mixed.
200 g of bright stock wax-containing hydrocarbon oil was tested according to the test method.

Examples 9 to 12 and Comparative Examples 11 to 15
Table 3 shows the dewaxing performance of the bright stock wax-containing hydrocarbon oil obtained in the above.

[0055]

[Table 3]

[0056]

As is apparent from Tables 1 to 3, the use of the dewaxing aid of the present invention in the dewaxing step can greatly improve the filtration rate. Comparative Examples 2-5, 7-10, 12-
In the case of No. 15, no dewaxing aid was used (Comparative Example 1,
The filtration speed and the yield are improved as compared with (6, 11). However, the three-type mixture according to the present invention has an effect of improving the filtration speed as compared with the comparative example. This is a special effect of the present invention.

Claims (2)

[Claims] 1. A wax is precipitated by dissolving a dewaxing solvent and a dewaxing aid in a wax-containing hydrocarbon oil and cooling, and the deposited wax is separated (by a liquid / solid separation method).
The dewaxing method of removing the dewaxed oil to obtain (A) 10 carbon atoms
Having an alkyl chain length of -20 and an average molecular weight of 10,000
~ 800,000 polyalkyl methacrylates,
(B) a polyalkyl (meth) acrylate having an alkyl chain length of 18 to 30 carbon atoms and having an average molecular weight of 10,000 to 800,000; and (C) an average molecular weight of 1,000 to 1
A dewaxing aid characterized by mixing three kinds of polyalkylated naphthalene condensates of 00000. 2. A + B / C = 10/1 when the dewaxing aid composed of components (A), (B) and (C) is A / B = 200/1 to 9/1 (weight ratio). ~ 1/10 ratio,
0.01 to 1.00 m based on wax-containing hydrocarbon oil
The dewaxing aid according to claim 1, which is added at an ass%.