阅读说明：本技术 一种用于分离芳烃的低共熔溶剂及用于分离芳烃的应用及方法 (Eutectic solvent for separating aromatic hydrocarbon, and application and method for separating aromatic hydrocarbon ) 是由 宋奇 郑均林 李成 于 2019-09-30 设计创作，主要内容包括：本发明涉及石油或石油馏分中芳烃分离领域的一种用于分离芳烃的低共熔溶剂及用于分离芳烃的应用及方法。所述低共熔溶剂,可包含氢键受体和氢键供体,所述的氢键供体/氢键受体的摩尔比例为0.2:1～21:1；所述氢键受体为有机氮化物的一种或多种。所述技术方案提出调整低共熔溶剂的氢键给体和氢键受体结构,使低共熔溶剂对芳烃亲和力增加,增加该溶剂的抽提芳烃的效率。同时,本发明亦可以与离子液体混合后作为复合萃取剂使用,以适应多种工况条件,应用前景广阔。(The invention relates to a eutectic solvent for separating aromatic hydrocarbon, and an application and a method for separating aromatic hydrocarbon, belonging to the field of separation of aromatic hydrocarbon in petroleum or petroleum fractions. The eutectic solvent can comprise a hydrogen bond acceptor and a hydrogen bond donor, wherein the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 0.2: 1-21: 1; the hydrogen bond acceptor is one or more of organic nitride. The technical proposal provides that the hydrogen bond donor and hydrogen bond acceptor structures of the eutectic solvent are adjusted, so that the affinity of the eutectic solvent to the aromatic hydrocarbon is increased, and the efficiency of the solvent for extracting the aromatic hydrocarbon is increased. Meanwhile, the invention can be used as a composite extracting agent after being mixed with ionic liquid so as to adapt to various working conditions and have wide application prospect.)

1. A eutectic solvent for separating aromatic hydrocarbons, characterized by comprising a hydrogen bond acceptor and a hydrogen bond donor,

the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 0.2: 1-21: 1; the hydrogen bond acceptor is one or more of organic nitride.

2. The eutectic solvent for separating aromatic hydrocarbons according to claim 1, wherein the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 0.5:1 to 20:1, preferably 0.5:1 to 8: 1.

3. The eutectic solvent for separating aromatic hydrocarbons according to claim 1 or 2, characterized in that:

the organic nitride is selected from one or more of organic ammonium compounds, imidazole nitrides and pyridine compounds.

4. The eutectic solvent for separating aromatic hydrocarbons according to claim 3, characterized in that:

the imidazole nitride has a structural general formula as follows:

wherein R is_a、R_bIndependently selected from C1-C18 alkyl, preferably C1-C4 alkyl; x is halogen.

5. The eutectic solvent for separating aromatic hydrocarbons according to claim 3, characterized in that: the pyridine compound has a structural general formula as follows:

wherein Rx and Ry are independently selected from C1-C18 alkyl, preferably C8-C16 alkyl; x is halogen.

6. The eutectic solvent for separating aromatic hydrocarbons according to claim 3, characterized in that:

the structural general formula of the organic ammonium is as follows:

wherein, R is₁、R₂、R₃、R₄Respectively and independently selected from one or more of C1-C18 alkyl, C1-C18 cycloalkyl, C1-C18 terminal alkylene, phenyl, benzyl, carboxyl alkyl and epoxy alkyl; preferably, R₁、R₂、R₃、R₄Respectively and independently selected from one or more of C1-C5 alkyl, C1-C5 terminal alkenyl, C1-C5 carboxylic acid alkyl and phenyl; x is halogen.

7. The eutectic solvent for separating aromatic hydrocarbons according to claim 1 or 2, characterized in that:

the hydrogen bond donor is selected from one or more of ethylene glycol, propylene glycol, glycerol, isopropanol, butanediol, pentanediol, hexanediol, ethyl glycolate, ethyl acetate, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, N-dimethylformamide, N-dimethylacetamide, urea, lactic acid, propionic acid, butyric acid, malic acid, citric acid, maleic acid, leucine, glycine, glutamic acid, alanine, sorbitol, isosorbide, glucose, xylose, fructose, maltose and arabinose; the polyethylene glycol is at least one selected from polyethylene glycol 100, polyethylene glycol 200, polyethylene glycol 300, polyethylene glycol 400, polyethylene glycol 600 and polyethylene glycol 800;

the hydrogen bond donor is preferably one or more of ethylene glycol, propylene glycol, glycerol, butanediol, pentanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol 200, polyethylene glycol 300, polyethylene glycol 400, polyethylene glycol 600, urea and lactic acid.

8. The eutectic solvent for separating aromatic hydrocarbons according to claim 1 or 2, characterized in that:

the organic nitride is selected from one or more of phenyl trimethyl ammonium halide, benzyl triethyl ammonium halide, benzyl dimethyl phenyl ammonium halide, dodecyl dimethyl benzyl ammonium halide, octadecyl dimethyl benzyl ammonium halide, 1, 3-dimethyl imidazole, 1-ethyl-3-methyl imidazole halide, 1-ethyl-3-methyl imidazole, 1-butyl-3-methyl imidazole halide, 1-butyl-3-methyl imidazole, halogenated octyl pyridine, halogenated pentadecyl pyridine and halogenated hexadecyl pyridine;

the organic nitride is preferably one or more of phenyltrimethylammonium halide, benzyltrimethylammonium halide, 1, 3-dimethylimidazole, 1-ethyl-3-methylimidazole halide, 1-ethyl-3-methylimidazole, 1-butyl-3-methylimidazole halide and 1-butyl-3-methylimidazole.

9. The method for preparing the eutectic solvent for separating aromatic hydrocarbons according to any one of claims 1 to 8, characterized by comprising the steps of:

mixing the hydrogen bond acceptor and the hydrogen bond donor according to the dosage at 0-200 ℃ to obtain the material; wherein the preferred temperature is 20-120 ℃.

10. Use of the eutectic solvent according to any one of claims 1 to 8 or the preparation method according to claim 9 for separating aromatic hydrocarbons.

11. Use of a eutectic solvent according to claim 10 for separation of aromatic hydrocarbons, characterized in that:

the eutectic solvent is used as an extracting agent in the separation of aromatic hydrocarbon; when the eutectic solvent is used as an extractant, the mass ratio of the eutectic solvent to the aromatic hydrocarbon-containing material flow is 0.1: 1-80: 1, preferably 0.3: 1-20: 1.

12. use of a eutectic solvent according to claim 10 for separation of aromatic hydrocarbons, characterized in that:

when the eutectic solvent is used as an extractant, the extraction temperature is 5-120 ℃, and preferably 15-90 ℃.

Technical Field

The invention relates to the field of separation of aromatic hydrocarbons in petroleum or petroleum fractions, and in particular relates to a eutectic solvent for separating aromatic hydrocarbons, and application and a method for separating aromatic hydrocarbons.

Background

The separation of aromatic hydrocarbons from non-aromatic hydrocarbons is an important step in industrial production. In industrial practice, the reacted material flow contains non-aromatic components such as alkane, cyclane and trace alkene besides aromatic hydrocarbon, and the non-aromatic components are close to the boiling point of the aromatic hydrocarbon, so that azeotrope is easy to form, and the separation difficulty is increased. The solvent extraction and extraction rectification technology developed in the existing industry has better separation effect and is widely applied, but has the problems of high energy consumption, easy deterioration of the extraction solvent, easy corrosion of the device and the like, and has still room for improvement in the technology. In addition, the effective separation of the polycyclic aromatic hydrocarbon in the aromatic hydrocarbon has important significance for upgrading the diesel oil and improving the enterprise benefit. Therefore, the development of a novel efficient green extraction solvent and the improvement of the separation efficiency of aromatic hydrocarbon are the future development directions.

The Deep Eutectic Solvent (DES) is used as a novel green solvent, has the properties similar to those of ionic liquid, extremely low volatility and stable physical properties, and shows excellent dissolving and separating capacity for various organic mixture systems. The eutectic solvent used in the separation process is generally formed by hydrogen bond acceptor (such as organic salt choline chloride, quaternary ammonium salt, quaternary phosphonium salt and the like) and hydrogen bond donor (such as urea, hexanediol, sorbitol, butanediol, malic acid, amino acid, glucose and the like), and thus has strong polarity. Eutectic solvents can also achieve a certain specific functional property by designing different combinations of hydrogen bond acceptors and hydrogen bond donors. Compared with the traditional ionic liquid, the eutectic solvent generally has polarity, is simple to prepare, has weak corrosivity, and can be biodegraded. Due to the excellent characteristics, the eutectic solvent has the tendency of replacing the traditional organic solvent and ionic liquid for chemical separation, has good application prospect in the extraction and separation of aromatic hydrocarbon and alkane mixtures, and is greatly concerned.

In the separation process of aromatic hydrocarbon and non-aromatic hydrocarbon, the higher the extraction rate of single-stage aromatic hydrocarbon and the purity of aromatic hydrocarbon in extract liquid are, the higher the extraction efficiency is, the lower the equipment investment required in continuous operation is, and the more the industrial application prospect is. The extraction rate of single-stage aromatics extracted at present is within 10 percent, and the purity of extracted aromatics is below 50 percent, so a new system needs to be developed to improve the extraction efficiency.

Disclosure of Invention

In order to solve the above problems in the prior art, the present invention provides a eutectic solvent for separating aromatic hydrocarbons. In particular to a eutectic solvent for separating aromatic hydrocarbon and application and a method thereof for separating aromatic hydrocarbon. The invention provides a method for adjusting the hydrogen bond donor and hydrogen bond acceptor structure of the eutectic solvent, so that the affinity of the eutectic solvent to aromatic hydrocarbon is increased, and the efficiency of the solvent for extracting the aromatic hydrocarbon is increased.

One of the purposes of the present invention is to provide a eutectic solvent for separating aromatic hydrocarbons, which may include a hydrogen bond acceptor and a hydrogen bond donor, wherein the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 0.2:1 to 21:1, preferably 0.5:1 to 20:1, more preferably 0.5:1 to 8:1, and further preferably 1:1 to 8: 1.

Wherein the content of the first and second substances,

the hydrogen bond acceptor may be one or more of an organic nitride; the organic nitride can be selected from one or more of organic ammonium compounds, imidazole nitrides and pyridine compounds.

Wherein the content of the first and second substances,

the imidazole nitride has a structural general formula as follows:

wherein R is_a、R_bCan be independently selected from alkyl of C1-C18, preferably alkyl of C1-C4; x is halogen.

The general structural formula of the pyridine compound can be as follows:

wherein Rx and Ry can be independently selected from C1-C18 alkyl, preferably C8-C16 alkyl; x is halogen;

the general structural formula of the organic ammonium can be:

wherein, R is₁、R₂、R₃、R₄Can be respectively and independently selected from one or more of C1-C18 alkyl, C1-C18 cycloalkyl, C1-C18 terminal alkylene, phenyl, benzyl, carboxyl alkyl and epoxy alkyl; preferably, R₁、R₂、R₃、R₄Can be respectively and independently selected from one or more of C1-C5 alkyl, C1-C5 terminal alkenyl, C1-C5 carboxylic acid alkyl and phenyl; x is halogen.

The organic nitrogen compound can be selected from one or more of phenyl trimethyl ammonium halide, benzyl triethyl ammonium halide, benzyl dimethyl phenyl ammonium halide, dodecyl dimethyl benzyl ammonium halide, octadecyl dimethyl benzyl ammonium halide, 1, 3-dimethyl imidazole halide, 1-ethyl-3-methyl imidazole halide, 1-butyl-3-methyl imidazole, halogenated octyl pyridine, halogenated pentadecyl pyridine and halogenated hexadecyl pyridine. The organic nitrogen compound is preferably one or more of phenyltrimethylammonium halide, benzyltrimethylammonium halide, 1, 3-dimethylimidazole, 1-ethyl-3-methylimidazole halide, 1-ethyl-3-methylimidazole, 1-butyl-3-methylimidazole halide and 1-butyl-3-methylimidazole. Wherein the halide is one of fluoride, chloride, bromide and iodide.

The hydrogen bond donor can be selected from one or more of ethylene glycol, propylene glycol, glycerol, isopropanol, butanediol, pentanediol, hexanediol, ethyl glycolate, ethyl acetate, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, N-dimethylformamide, N-dimethylacetamide, urea, lactic acid, propionic acid, butyric acid, malic acid, citric acid, maleic acid, leucine, glycine, glutamic acid, alanine, sorbitol, isosorbide, glucose, xylose, fructose, maltose, arabinose; wherein, the polyethylene glycol can be selected from one or more of polyethylene glycol 100, polyethylene glycol 200, polyethylene glycol 300, polyethylene glycol 400, polyethylene glycol 600 and polyethylene glycol 800; the hydrogen bond donor is preferably one or more of ethylene glycol, propylene glycol, glycerol, butanediol, pentanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol 200, polyethylene glycol 300, polyethylene glycol 400, polyethylene glycol 600, urea and lactic acid.

The invention also aims to provide a preparation method of the eutectic solvent for separating the aromatic hydrocarbon. The method may comprise the steps of:

and (3) uniformly mixing and stirring the hydrogen bond acceptor and the hydrogen bond donor according to the dosage at 0-200 ℃ to obtain the material. Wherein the preferred temperature is 20-120 ℃.

The invention also aims to provide the method for separating the aromatic hydrocarbon by using the eutectic solvent.

Wherein the content of the first and second substances,

when the eutectic solvent is used as an extractant, the mass ratio of the eutectic solvent to the aromatic hydrocarbon-containing material flow is 0.1:1 to 80:1, preferably 0.1:1 to 50:1, and more preferably 0.3: 1-20: 1. the extraction temperature can be 5 ℃ to 120 ℃, preferably 15 ℃ to 90 ℃.

Considering that the separation target is to separate aromatic hydrocarbon from alkane, when DES is designed, benzene ring and/or aromatic heterocyclic group is introduced into the structure of hydrogen bond acceptor, the original alkyl substituted organic nitride is changed into phenyl and/or aromatic heterocyclic group substituted organic nitride, and the affinity of benzene ring and/or aromatic heterocyclic ring is utilized to improve the solubility of aromatic hydrocarbon. Meanwhile, polyether, alcohol and ester which are beneficial to aromatic hydrocarbon separation and contain polyhydroxy, carboxyl and carbon-oxygen bonds are used as hydrogen bond donors, the electronic property of nitrogen atoms on the organic nitride is further modulated, and the solubility of aromatic hydrocarbon is increased. The present invention has been completed through trial and error based on the above idea. According to the invention, the high-efficiency extraction of aromatic hydrocarbon can be realized.

Detailed Description

The following detailed description of the embodiments of the present invention is provided, but it should be noted that the scope of the present invention is not limited by the embodiments, but is defined by the appended claims.

All publications, patent applications, patents, and other references mentioned in this specification are herein incorporated by reference in their entirety. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In case of conflict, the present specification, including definitions, will control.

When the specification concludes with the claims with the term "prior art" or similar language to derive materials, substances, methods, steps, devices, or components, etc., it is intended that the subject matter derived from the term encompass those conventionally used in the art when presented in this application, but also includes those not currently used in the art, but will become known in the art to be suitable for a similar purpose.

In the context of the present specification, anything or things which are not mentioned, except where explicitly stated, are directly applicable to those known in the art without any changes. Moreover, any embodiment described herein may be freely combined with one or more other embodiments described herein, and the technical solutions or concepts resulting therefrom are considered part of the original disclosure or original disclosure of the invention, and should not be considered as new matters not disclosed or contemplated herein, unless a person skilled in the art would consider such a combination to be clearly unreasonable.

Any particular value disclosed herein (including endpoints of ranges of values) is not to be limited to the precise value of that value, but rather is to be understood to also encompass values close to the precise value, i.e., to be understood as modified by the term "about". Also, for the disclosed ranges of values, any combination between the endpoints of the ranges, between the endpoints and specific points within the ranges, and between specific points within the ranges can result in one or more new ranges of values, which should also be considered as specifically disclosed herein.

To describe the results of the present invention, in the context of the present specification, the results of the test are described in terms of "single stage aromatics extraction" (A%) and extract aromatics purity (P%). The method for calculating the single-stage aromatic extraction rate comprises the following steps: and A%, (total aromatic hydrocarbon content of raw oil-total aromatic hydrocarbon content after extraction)/total aromatic hydrocarbon content in raw oil x 100%. Higher A% values indicate better single extraction. The withdrawn aromatics purity (P%) -the aromatics content in the extracted oil/total amount of withdrawn hydrocarbons. In the invention, the raw oil is obtained by mixing tetrahydronaphthalene and tridecane, and the mass ratio of the tetrahydronaphthalene to the tridecane is 70/30.

The invention is further illustrated by the following examples.

The starting materials used in the examples are all commercially available.

[ COMPARATIVE EXAMPLE 1 ]

Weighing 14g of hydrogen bond acceptor choline chloride, weighing 27.6g of hydrogen bond donor glycerol, wherein the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 3, mixing, heating to 50 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent DES. Adding raw oil into the eutectic solvent to mix. Wherein the mass ratio of DES to raw oil is 1, and the extraction process is carried out at 25 deg.C. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 24 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer for gas chromatography analysis, and calculating to obtain single-stage aromatic extraction rate A% of 14% and aromatic purity P% of 35%.

[ example 1 ]

Weighing 8.6g of hydrogen bond acceptor phenyltrimethyl ammonium chloride, weighing 22.5g of hydrogen bond donor triethylene glycol, wherein the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 3, mixing, heating to 50 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent. And adding raw oil into the eutectic solvent for mixing, wherein the mass ratio of DES to raw oil is 1, and the extraction process is carried out at 25 ℃. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 24 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer, and performing gas chromatography to obtain a single-stage aromatic extraction rate A% of 40% and an aromatic purity P% of 85%.

[ example 2 ]

Weighing 9.3g of hydrogen bond acceptor benzyltrimethylammonium chloride, weighing 100g of hydrogen bond donor polyethylene glycol 400, mixing, heating to 60 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent. And adding raw oil into the eutectic solvent for mixing, wherein the mass ratio of DES to raw oil is 1, and the extraction process is carried out at 25 ℃. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 24 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer for gas chromatography analysis, and calculating to obtain a single-stage aromatic extraction rate A% of 52% and an aromatic purity P% of 88%.

[ example 3 ]

Weighing 9.1g of hydrogen bond acceptor benzyltriethylammonium chloride, weighing 24g of hydrogen bond donor polyethylene glycol 200, wherein the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 3, mixing, heating to 60 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent. And adding raw oil into the eutectic solvent for mixing, wherein the mass ratio of DES to raw oil is 1, and the extraction process is carried out at 30 ℃. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 24 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer, and performing gas chromatography to obtain single-stage aromatic extraction A% of 50% and aromatic purity P% of 89%.

[ example 4 ]

Weighing 4.8g of hydrogen bond acceptor 1, 3-dimethylimidazole, weighing 2.7g of hydrogen bond donor diethylene glycol, wherein the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 2, mixing, heating to 60 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent.

And adding raw oil into the eutectic solvent for mixing, wherein the mass ratio of DES to raw oil is 1, and the extraction process is carried out at 25 ℃. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 24 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer, and performing gas chromatography to obtain a single-stage aromatic extraction rate A% of 53% and an aromatic purity P% of 96%.

[ example 5 ]

Weighing 3.8g of hydrogen bond acceptor 1, 3-dimethyl imidazole, weighing 120g of hydrogen bond donor polyethylene glycol 600, mixing, heating to 40 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent. And adding raw oil into the eutectic solvent for mixing, wherein the mass ratio of DES to raw oil is 1, and the extraction process is carried out at 25 ℃. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 24 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer, and performing gas chromatography to obtain single-stage aromatic extraction A% of 55% and aromatic purity P% of 90%.

[ example 6 ]

Weighing 3.8g of hydrogen bond acceptor 1, 3-dimethyl imidazole, weighing 28.8g of hydrogen bond donor lactic acid, wherein the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 8, mixing, heating to 120 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent. And adding raw oil into the eutectic solvent for mixing, wherein the mass ratio of DES to raw oil is 1, and the extraction process is carried out at 60 ℃. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 24 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer for gas chromatography analysis, and calculating to obtain single-stage aromatic extraction rate A% of 43% and aromatic purity P% of 92%.

[ example 7 ]

Weighing 6.6g of hydrogen bond acceptor chlorinated 1, 3-dimethylimidazole, weighing 120g of hydrogen bond donor polyethylene glycol 800, wherein the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 3, mixing, heating to 80 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent. And adding raw oil into the eutectic solvent for mixing, wherein the mass ratio of DES to raw oil is 1, and the extraction process is carried out at 25 ℃. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 24 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer, and performing gas chromatography to obtain a single-stage aromatic extraction rate A% of 49% and an aromatic purity P% of 85%.

[ example 8 ]

Weighing 5.3g of hydrogen bond acceptor chlorinated 1, 3-dimethylimidazole, and 56g of hydrogen bond donor tetraethylene glycol, wherein the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 7, mixing, heating to 80 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent. And adding raw oil into the eutectic solvent for mixing, wherein the mass ratio of DES to raw oil is 1, and the extraction process is carried out at 80 ℃. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 24 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer for gas chromatography analysis, and calculating to obtain a single-stage aromatic extraction rate A% of 51% and an aromatic purity P% of 91%.

[ example 9 ]

Weighing 6.9g of hydrogen bond acceptor phenyltrimethylammonium chloride, weighing 60g of hydrogen bond donor/hydrogen bond acceptor polyethylene glycol 300, mixing, heating to 50 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent. And adding raw oil into the eutectic solvent for mixing, wherein the mass ratio of DES to raw oil is 1, and the extraction process is carried out at 25 ℃. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 24 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer, and performing gas chromatography analysis to obtain a single-stage aromatic extraction rate A% of 52% and an aromatic purity P% of 87%.

[ example 10 ]

Weighing 8.6g of hydrogen bond acceptor phenyltrimethylammonium chloride, weighing 19.7g of hydrogen bond donor ethylene glycol, wherein the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 6, mixing, heating to 25 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent. Adding raw oil into the eutectic solvent, mixing, wherein the mass ratio of DES to raw oil is 0.3, and extracting at 15 deg.C. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 24 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer for gas chromatography analysis, and calculating to obtain single-stage aromatic extraction rate A% of 42% and aromatic purity P% of 90%.

[ example 11 ]

Weighing 5.6g of hydrogen bond acceptor 1-butyl-3-methylimidazole and 18g of hydrogen bond donor triethylene glycol, wherein the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 3, mixing, heating to 50 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent. And adding raw oil into the eutectic solvent for mixing, wherein the mass ratio of DES to raw oil is 2, and the extraction process is carried out at 60 ℃. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 24 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer, and performing gas chromatography to obtain single-stage aromatic extraction A% of 55% and aromatic purity P% of 86%.

[ example 12 ]

Weighing 6.6g of hydrogen bond acceptor 1-butyl-3-methylimidazolium bromide, weighing 5.4g of hydrogen bond donor urea, wherein the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 3, mixing, heating to 50 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent. And adding raw oil into the eutectic solvent for mixing, wherein the mass ratio of DES to raw oil is 10, and the extraction process is carried out at 50 ℃. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 24 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer, and performing gas chromatography analysis to obtain a single-stage aromatic extraction rate A% of 50% and an aromatic purity P% of 91%.

[ example 13 ]

Weighing 6.6g of hydrogen bond acceptor 1-butyl-3-methylimidazolium bromide, weighing 8.3g of hydrogen bond donor glycerol, wherein the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 3, mixing, heating to 60 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent. And adding raw oil into the eutectic solvent for mixing, wherein the mass ratio of DES to raw oil is 20, and the extraction process is carried out at 40 ℃. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 24 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer, and performing gas chromatography to obtain a single-stage aromatic extraction rate A% of 46% and an aromatic purity P% of 85%.

[ example 14 ]

Weighing 5.6g of hydrogen bond acceptor benzyltrimethyl ammonium chloride, 8.3g of hydrogen bond donor triethylene glycol and 5.4g of urea, wherein the molar ratio of the triethylene glycol to the urea to the benzyltrimethyl ammonium chloride is 2 and 3 respectively, mixing the triethylene glycol, the urea and the benzyltrimethyl ammonium chloride, heating to 60 ℃, stirring to obtain a uniform and transparent solution, and cooling to room temperature to obtain the eutectic solvent. And adding raw oil into the eutectic solvent for mixing, wherein the mass ratio of DES to raw oil is 5, and the extraction process is carried out at 40 ℃. The eutectic solvent and model oil were mixed vigorously 5 times and allowed to stand for 37 hours to reach full equilibrium. The mixed liquid after extraction is automatically divided into an upper layer and a lower layer, the upper layer is residual model oil, and the lower layer is a DES layer extracted with aromatic hydrocarbon. Taking out a small amount of upper layer model oil and the lower layer DES layer, and performing gas chromatography to obtain a single-stage aromatic extraction rate A% of 59% and an aromatic purity P% of 89%.

TABLE 1