Method and system for separating components in shale oil

Abstract

The invention provides a method and a system for separating components in shale oil, and relates to the field of petrochemical industry. The method comprises the following steps: removing n-alkane wax in shale oil by adopting a lost wax method to obtain distillate oil with cycloalkane and aromatic hydrocarbon; cutting the distillate oil with cycloalkane and aromatic hydrocarbon to obtain cut shale oil; and performing purification operation on the cut shale oil of which the temperature is less than or equal to the set temperature to obtain a fraction with cycloalkanes and a fraction with aromatic hydrocarbons. The method is used for achieving the effect of separating the cycloalkane and the aromatic hydrocarbon from the shale oil with the complex cluster composition with low energy consumption.

Description

Technical Field

[0001] This application relates to the field of petrochemicals, and in particular to a method and system for separating components in shale oil. Background Technology

[0002] Shale oil is a petroleum resource located in shale formations. my country has abundant reserves of continental shale oil, mainly composed of diesel and higher fractions, including alkanes, cycloalkanes, aromatics, and small amounts of heteroatom organic compounds. Alkanes account for 50%, cycloalkanes for approximately 40%, and aromatics and heteroatom organic compounds for 10%. Currently, the processing of continental shale oil mainly relies on a series of complex refining technologies, including primary separation, distillation, catalytic cracking, and hydrotreating. However, these processes do not fully utilize their inherent characteristics, resulting in a low proportion of value-added chemical products. Resource utilization and efficiency maximization still need improvement, especially the insufficient utilization of cycloalkanes and aromatics.

[0003] Currently, the extraction of cycloalkanes and aromatics from shale oil typically employs solvent extraction. Specifically, this method leverages the differences in solubility of different components in shale oil to separate these components from those that are insoluble or sparingly soluble in the solvent. During solvent extraction, the solvent comes into countercurrent contact with the shale oil, allowing the solvent to preferentially extract the cycloalkanes and aromatics. However, this method requires significant energy consumption to separate cycloalkanes and aromatics from shale oil with its complex cluster composition. Summary of the Invention

[0004] This application provides a method and system for separating components in shale oil, which can achieve the effect of separating cycloalkanes and aromatics from shale oil with complex cluster composition with low energy consumption.

[0005] In a first aspect, this application provides a method for separating components in shale oil, comprising:

[0006] The lost-wax method is used to remove n-alkane wax from shale oil, yielding distillate oil containing cycloalkanes and aromatics;

[0007] Cutting the distillate containing cycloalkanes and aromatics yields cut shale oil;

[0008] Purification operations are performed on the cut shale oil at temperatures below or equal to a set temperature to obtain fractions containing cycloalkanes and fractions containing aromatics.

[0009] In an optional embodiment, when the dewaxing process includes a dewaxing aid, the dewaxing aid is a mixture of a low molecular weight ethylene-methyl acrylate copolymer with a weight average molecular weight of 10,000 g / mol to 100,000 g / mol and a high molecular weight ethylene-methyl acrylate copolymer with a weight average molecular weight of 100,000 g / mol to 300,000 g / mol.

[0010] In one optional embodiment, the blending ratio of the low molecular weight ethylene-methyl acrylate copolymer and the high molecular weight ethylene-methyl acrylate copolymer is 1:10 to 10:1.

[0011] In an optional embodiment, when the lost-wax process includes an activator, the activator is selected from at least one of alcohol activators, ether activators, and deionized aqueous solutions.

[0012] In one optional embodiment, the activator is a liquid cycloalkanol having C3 to C10 carbon atoms, and / or the activator is an ion-free aqueous solution of a cycloalkanol having C3 to C10 carbon atoms, wherein the cycloalkanol in the liquid cycloalkanol, and / or the cycloalkanol in the ion-free aqueous solution of the cycloalkanol is a mixture of at least two liquid cycloalkanols having C3 to C10 carbon atoms.

[0013] In one optional embodiment, when the lost-wax process includes urea, a solvent, and an activator, the solvent is selected from an ion-free aqueous solution, the activator is selected from cycloalkanols, and the mass ratio of urea to activator is 20:1 to 1:1.

[0014] In an optional embodiment, when the lost-wax process includes a solvent, the solvent is selected from at least one of alcohol solvents, ether solvents, and non-ionized aqueous solutions.

[0015] In one optional embodiment, the solvent is a liquid cycloalkanol having C3 to C10 carbon atoms, and / or the solvent is an ion-free aqueous solution of a cycloalkanol having C3 to C10 carbon atoms, wherein the cycloalkanol in the liquid cycloalkanol, and / or the cycloalkanol in the ion-free aqueous solution of the cycloalkanol is a mixture of at least two or more liquid cycloalkanols having C3 to C10 carbon atoms.

[0016] In an optional embodiment, the above-mentioned lost-wax method is used to remove n-alkane wax from shale oil, yielding a distillate oil containing cycloalkanes and aromatics, comprising:

[0017] A urea solution was prepared based on urea, solvent, and dewaxing agent, and the urea solution was heated to a set temperature.

[0018] Add the first set amount of shale oil into the reaction vessel and maintain the set stirring speed;

[0019] The second set amount of activator is added to the reaction vessel in batches;

[0020] Set the reaction conditions for the complexation reaction so that urea and shale oil can undergo a complexation reaction;

[0021] After the reaction vessel has been allowed to stand for a set time, a solid-liquid separation method is used to obtain a distillate oil containing cycloalkanes and aromatics.

[0022] Secondly, this application provides a component separation system for shale oil, the separation system including a removal system, a fractionation system, and a purification system, wherein...

[0023] The dewaxing system is used to remove n-alkane wax from shale oil using the lost-wax method, to obtain distillate oil containing cycloalkanes and aromatics;

[0024] A segmentation system is used to cut distillate oil containing cycloalkanes and aromatics to obtain cut shale oil;

[0025] The purification system is used to perform purification operations on cut shale oil at temperatures below or equal to a set temperature to obtain fractions containing cycloalkanes and fractions containing aromatics.

[0026] This application provides a method and system for component separation in shale oil, relating to the petrochemical field. The method includes: removing n-alkane wax from shale oil using a lost-wax process to obtain a distillate oil containing cycloalkanes and aromatics; cutting the distillate oil containing cycloalkanes and aromatics to obtain cut shale oil; and performing purification operations on the cut shale oil at a temperature below or equal to a set temperature to obtain a distillate oil containing cycloalkanes and a distillate oil containing aromatics. This application employs a sequential process of "removing n-alkane wax + cutting the distillate oil containing cycloalkanes and aromatics + purification of light distillate oil." This sequential process is highly targeted and can achieve the effect of separating cycloalkanes and aromatics from shale oil with complex cluster compositions at a relatively low cost. Attached Figure Description

[0027] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0028] Figure 1 This application provides a method for separating components in shale oil;

[0029] Figure 2 The chromatogram of shale oil provided in this application.

[0030] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0032] Currently, the shale oils explored and developed in my country are mainly continental shale oils. The composition and molecular structure of continental shale oils differ significantly from conventional petroleum. They exhibit a wide distribution of carbon numbers in their hydrocarbon composition, with small differences in the content of hydrocarbons with different carbon numbers, numerous isomers, and a mixture of mono- and polycyclic aromatic hydrocarbons, making separation difficult. Separating cycloalkanes and aromatics from shale oil requires high energy consumption in the processing technology.

[0033] To address the aforementioned issues and separate cycloalkanes and aromatics from shale oil with complex cluster compositions using lower energy consumption, this application provides a method for separating cycloalkanes and aromatics from shale oil. This method employs a sequential process of "removing n-alkane wax + cutting cycloalkanes and aromatics-rich fractions + purifying light cycloalkanes fractions + purifying heavy cycloalkanes fractions".

[0034] This application provides a method for separating components in shale oil; the specific steps are described in [reference needed]. Figure 1 , Figure 1 This application provides a method for separating components in shale oil. For example... Figure 1 As shown, this step includes:

[0035] 1) The dewaxing method is used to remove n-alkane wax from shale oil to obtain distillate oil containing cycloalkanes and aromatics. The dewaxing method can be a single-stage dewaxing method or, as needed, a multi-stage dewaxing method with two or more stages to achieve the desired separation effect. The multi-stage dewaxing method with two or more stages is preferred.

[0036] 2) Cutting the oil fraction containing cycloalkanes and aromatics to obtain the cut shale oil. For example, by using distillation, the oil fraction containing cycloalkanes and aromatics is cut into fractions with temperatures ≤200℃ and >200℃. Specifically: the kettle temperature is controlled at 300℃~500℃; the distillation outlet temperature is controlled at 30℃~170℃, preferably 45℃~120℃, more preferably 60℃~100℃; the condensation temperature of the distillate (C5~C10 cycloalkanes fraction) is controlled at -50℃~50℃, preferably -10℃~30℃, more preferably 0℃~10℃; the pressure is controlled at -0.1MPa~0.1MPa, preferably -0.05MPa~0.05MPa, more preferably -0.01MPa~0.01MPa; the reflux ratio is controlled at 5:1~0:1, preferably 3:1~0.5:1, more preferably 1.5:1~1:1; the distillation column can be any known structure, preferably a packed column; depending on the required throughput, either batch operation or continuous operation can be selected, preferably continuous operation.

[0037] 3) Perform purification operations on the shale oil cut at temperatures less than or equal to the set temperature to obtain fractions containing cycloalkanes and aromatics. For example, the method in CN201810156076.1 can be used to further purify the shale oil cut at ≤200℃ to obtain cycloalkanes and aromatics with boiling points ≤200℃, and simultaneously obtain a fraction rich in branched alkanes with boiling points ≤200℃.

[0038] By employing a sequential process of "removing n-alkane wax + cutting cycloalkanes and aromatics fractions + purifying fractions at temperatures below or equal to a set point," this highly targeted approach can separate cycloalkanes and aromatics from shale oil with complex cluster compositions with relatively low process energy consumption. Under suitable conditions, single-stage or multi-stage urea dewaxing can remove most of the wax, primarily n-alkanes, from the fractions, significantly reducing the energy consumption of subsequent processes and substantially increasing the concentration of cycloalkanes and aromatics in the residual oil.

[0039] This application also provides a component separation system for shale oil. The separation system includes a removal system, a segmentation system, and a purification system. The removal system is used to remove n-alkane wax from the shale oil using a lost-wax method to obtain a distillate oil containing cycloalkanes and aromatics. The segmentation system is used to cut the distillate oil containing cycloalkanes and aromatics to obtain cut shale oil. The purification system is used to perform a purification operation on the cut shale oil at a temperature less than or equal to a set temperature to obtain a distillate oil containing cycloalkanes and a distillate oil containing aromatics.

[0040] In one specific embodiment, the above-mentioned lost-wax method removes n-alkane wax from shale oil to obtain a distillate oil containing cycloalkanes and aromatics. The method includes: preparing a urea solution based on urea, a solvent, and a dewaxing aid, and heating the urea solution to a set temperature; adding a first set amount of shale oil to a reaction vessel while maintaining a set stirring speed; adding a second set amount of activator to the reaction vessel in batches; setting the reaction conditions for a complexation reaction to allow urea to undergo a complexation reaction with the shale oil; and after the reaction vessel has settled for a set time, using a solid-liquid separation method to obtain the distillate oil containing cycloalkanes and aromatics. In the complexation reaction, temperature, time, pressure, and settling time are key parameters that need to be precisely controlled to ensure reaction efficiency, selectivity, and product quality. Values ​​that are too low or too high may lead to a reduced reaction rate, increased byproducts, or equipment safety hazards. Therefore, controlling the temperature, time, pressure, and settling time within the following ranges ensures the normal progress of the reaction and maximizes the reaction conversion rate.

[0041] The settling time of the mixture obtained from the complexation reaction is 0.5 h to 72 h, preferably 1 h to 48 h, more preferably 2 h to 24 h. The temperature of the complexation reaction is controlled between -30 °C and 100 °C, preferably 0 °C to 70 °C, more preferably 10 °C to 50 °C. In particular, during the complexation reaction, the temperature of the complexation reaction can be adjusted as needed, and is not limited to a single complexation reaction temperature. The temperature adjustment rate is ±2 °C / min, preferably ±1 °C / min, more preferably ±0.5 °C / min.

[0042] The complexation reaction time is controlled within 0.5 h to 48 h, preferably 1 h to 24 h, and more preferably 2 h to 8 h. The isothermal reaction time at each temperature is controlled within 0.5 h to 8 h, preferably 0.5 h to 4 h, and more preferably 1 h to 2 h.

[0043] The pressure of the complexation reaction is controlled at -0.1 MPa to 0.1 MPa, preferably -0.05 MPa to 0.05 MPa, more preferably -0.01 MPa to 0.01 MPa, and in particular, the complexation reaction is completed under 0 MPa conditions.

[0044] Solid-liquid separation of the mixture obtained by complexation reaction can be accomplished using existing mature solid-liquid separation technologies.

[0045] In the complexation reaction, the mass ratio of solvent to urea is controlled at 20:1 to 1:2, preferably 10:1 to 1:1, and more preferably 5:1 to 2:1.

[0046] In the complexation reaction, when deionized water is used as the solvent, the activator is preferably a cycloalkanol, more preferably a mixture of at least two or more liquid cycloalkanols having C3 to C10 carbon atoms, and the mass ratio of urea to activator is controlled at 20:1 to 1:1, preferably 10:1 to 1:1, more preferably 5:1 to 1:1.

[0047] Based on the mass of the shale oil processed, the mass ratio of urea solution to shale oil (urea-oil ratio) in the complexation reaction is controlled at 45:1 to 1:1, preferably 20:1 to 5:1, and more preferably 15:1 to 10:1. Based on the mass of the shale oil processed, the mass ratio of dewaxing aid to shale oil in the complexation reaction is controlled at 0.001:100 to 1:100, preferably 0.005:1 to 0.05:1, and more preferably 0.01:1 to 0.05:1.

[0048] In one specific embodiment, the urea may be selected from the following varieties: industrial urea or agricultural urea or mixtures thereof, preferably a single industrial urea or a mixture of two or more industrial urea. The particle size of the urea is 0.85 mm to 4.75 mm, preferably 0.85 mm to 3.35 mm, and more preferably 0.85 mm to 2.8 mm.

[0049] In one specific embodiment, when the lost-wax process includes a solvent, the solvent is selected from at least one of alcohol solvents, ether solvents, and deionized aqueous solutions. That is, the solvent can be selected from at least one of alcohol solvents, ether solvents, and deionized water, preferably at least one of alcohol solvents and / or deionized water, and more preferably cycloalkanols or deionized aqueous solutions of cycloalkanols.

[0050] Specifically, the solvent is a liquid cycloalkanol with C3 to C10 carbon atoms, and / or, the solvent is an ion-free aqueous solution of a cycloalkanol with C3 to C10 carbon atoms. More specifically, the cycloalkanol in the liquid cycloalkanol, and / or, the cycloalkanol in the ion-free aqueous solution of the cycloalkanol, is a mixture of at least two or more liquid cycloalkanols with C3 to C10 carbon atoms. Using a mixture of small-molecule cycloalkanols and large-molecule cycloalkanols and / or their ion-free aqueous solutions as the solvent for dewaxing urea in shale oil fractions rich in cycloalkanes and aromatics is well-suited to the wide carbon number distribution characteristic of continental shale oil in my country. During the complexation reaction, it promotes good molecular contact between n-alkanes with different carbon numbers in the shale oil and urea in the oil phase, urea liquid phase, solid phase complexes, and the surface of urea crystals, facilitating molecular rearrangement and accelerating heat and mass transfer and reaction rates.

[0051] In one specific embodiment, when the dewaxing process includes a dewaxing aid, the dewaxing aid may be selected from the following: microcrystalline wax, a polymer or a mixture of at least two or more substances, preferably a polymer or a mixture of two or more polymer substances, more preferably an ethylene-acrylate monomer copolymer, and more particularly, the dewaxing aid for shale oil urea dewaxing is a mixture of at least two or more ethylene-acrylate monomer copolymers.

[0052] Specifically, ethylene-methyl acrylate copolymer is used as a dewaxing aid. The ethylene-methyl acrylate copolymer used as the dewaxing aid in this application has a weight-average molecular weight of 10,000 g / mol to 300,000 g / mol, preferably 50,000 g / mol to 250,000 g / mol, and more preferably 100,000 g / mol to 20,000 g / mol.

[0053] More specifically, the dewaxing aid is a mixture of low molecular weight ethylene-methyl acrylate copolymers with a weight average molecular weight of 10,000 g / mol to 100,000 g / mol and high molecular weight ethylene-methyl acrylate copolymers with a weight average molecular weight of 100,000 g / mol to 300,000 g / mol. In one specific embodiment, the mixing ratio of the low molecular weight ethylene-methyl acrylate copolymers to the high molecular weight ethylene-methyl acrylate copolymers is 1:10 to 10:1. Using a mixture of low molecular weight ethylene-methyl acrylate copolymers and high molecular weight ethylene-methyl acrylate copolymers as a dewaxing aid for urea dewaxing of cycloalkanes and aromatic fractions in shale oil is highly targeted and can well adapt to the heavy composition characteristics of continental shale oil in my country, balancing the removal effect of low molecular weight waxes and high molecular weight waxes in shale oil. Furthermore, ethylene-methyl acrylate copolymers of different molecular weights can well combine with wax molecules and urea of ​​different ranges, which is beneficial to the aggregation of wax molecules in shale oil and their complexation with urea.

[0054] In one specific embodiment, when the dewaxing process includes an activator, the activator is selected from at least one of alcohol activators, ether activators, and deionized aqueous solutions, preferably alcohol activators, and more preferably cycloalkanols. Specifically, the cycloalkanol used as the activator for shale oil urea dewaxing is a liquid cycloalkanol having C3 to C10 carbon atoms.

[0055] More specifically, the activator is a liquid cycloalkanol with C3 to C10 carbon atoms, and / or, the activator is an ion-free aqueous solution of a cycloalkanol with C3 to C10 carbon atoms, wherein the cycloalkanol in the liquid cycloalkanol, and / or, the cycloalkanol in the ion-free aqueous solution of the cycloalkanol, is a mixture of at least two liquid cycloalkanols with C3 to C10 carbon atoms. Using a mixture of small-molecule and large-molecule cycloalkanols and / or their ion-free aqueous solutions as the activator for dewaxing urea in shale oil fractions rich in cycloalkanes and aromatics is well-suited to the wide carbon number distribution characteristic of continental shale oil in my country. During the complexation reaction, it promotes good molecular contact between n-alkanes with different carbon numbers and urea in the oil phase, urea phase, solid phase complexes, and the surface of urea crystals, facilitating molecular rearrangement and accelerating heat and mass transfer and reaction rates.

[0056] In one specific embodiment, when the lost-wax method includes urea, solvent, and activator, the solvent is selected from deionized aqueous solutions, the activator is selected from cycloalkanols, and the mass ratio of urea to activator is 20:1 to 1:1.

[0057] The implementation of this application has at least the following advantages: 1) It adopts a sequential process of "removing n-alkane wax + cutting distillate oil containing cycloalkanes and aromatics + purifying light distillate oil", which is highly targeted and can separate cycloalkanes and aromatics from shale oil with complex cluster composition with low process energy consumption; 2) It uses a mixture of low molecular weight ethylene-methyl acrylate copolymer and high molecular weight ethylene-methyl acrylate copolymer as a dewaxing aid for urea dewaxing of distillate oil rich in cycloalkanes and aromatics. It is highly targeted and can well adapt to the heavy composition characteristics of continental shale oil in my country, and balance the removal effect of small molecular wax and large molecular wax in shale oil. Ethylene-methyl acrylate copolymers of different molecular weights can well integrate with wax molecules and urea of ​​different ranges, which is beneficial to the aggregation of wax molecules in shale oil and their complexation with urea; 3) Using a mixture of small molecule cycloalkanols and large molecule cycloalkanols and / or their deionized aqueous solutions as solvents and / or activators for dewaxing urea in shale oil fractions rich in cycloalkanes and aromatics can well adapt to the wide carbon number distribution of continental shale oil in my country. During the complexation reaction, it promotes good molecular contact between n-alkanes and urea with different carbon numbers in shale oil and on the surface of oil phase, urea liquid phase, solid phase complexes, and urea crystals, which facilitates molecular rearrangement and accelerates heat and mass transfer and reaction rate.

[0058] The preparation method of naphthol compounds provided by the present invention will be further described below with reference to specific embodiments.

[0059] Unless otherwise specified, the experimental methods used in the following embodiments can be conventional methods in the art.

[0060] In the following embodiments, unless otherwise specified, all raw materials can be obtained by commercial purchase or conventional methods.

[0061] Source of raw materials or equipment: Shale oil, Daqing Gulong shale oil. Analysis results of the Gulong shale oil raw materials are shown in Table 1. Chromatographic spectra of the shale oil are for reference. Figure 2 , Figure 2 The chromatogram of shale oil provided in this application is used to determine the presence and relative content of various compounds in the shale oil.

[0062] Table 1 Properties of Shale Oil Feedstocks

[0063]

[0064] Urea, Kunlun brand industrial urea;

[0065] Cyclohexanol, purity 99%;

[0066] Cyclopropanol, purity 97%;

[0067] Deionized water;

[0068] Ethylene-methyl acrylate copolymer, after remelting, is sieved according to molecular weight, with a molecular weight of 50,000 g / mol to 300,000 g / mol.

[0069] Analytical instruments:

[0070] Colorimetric analysis;

[0071] Mass spectrometry;

[0072] Evaluation and analysis methods:

[0073] Simulated distillation was analyzed according to the method of ASTM D6352;

[0074] The composition of the oil fraction at 175–365℃ was analyzed according to the method in NB / SH / T0606-2019;

[0075] The composition of distillate oils at 200℃ and above was analyzed according to the methods of ASTM-D2786-91-2016 and ASTM-D3239-91-2016. Specific implementation examples:

[0077] (1) Dewaxing of shale oil with urea

[0078] Selection of raw materials

[0079] Three types of Gulong shale oil with different compositions were used to investigate the cutting conditions of shale oil. The analysis results of the Gulong shale oil feedstock are shown in Table 1.

[0080] The urea used in the urea dewaxing experiment is classified according to the particle diameter of commercially available finished urea, according to the national standard GB / T2440-2017: small particle urea (particle diameter 0.85mm~2.8mm), relatively small particle urea (particle diameter 1.18mm~3.35mm), relatively large particle urea (particle diameter 2.0mm~4.75mm), and large particle urea (particle diameter 4.0mm~8.0mm).

[0081] Preparation of urea solution

[0082] Weigh out the required proportions of urea, solvent, and / or activator, add the weighed urea, solvent, and / or activator to the container in sequence, start stirring, and allow the urea, solvent, and / or activator to fully dissolve under certain temperature and pressure to form a urea solution.

[0083] Complexation reaction

[0084] A certain amount of shale oil was weighed and added to the prepared urea solution to form a mixture of shale oil and urea solution. A certain amount of dewaxing agent was then weighed and added to the mixture. The mixture was kept at a certain temperature and stirred for a specified time before stirring was stopped and allowed to stand, yielding a reaction mixture after urea dewaxing. The reaction mixture was separated by centrifugation to obtain a dewaxed solution and a urea inclusion complex solid. The yield of the dewaxed solution was calculated using the following formula: Dewaxed solution yield = (Mass of liquid obtained from solid-liquid separation - Solvent content) / Amount of shale oil added × 100%.

[0085] Example 1

[0086] Weigh 15g of small-particle urea from Daqing, 30g of a mixture of cyclopropanol and nonanol (1:1), and add the weighed urea and cyclopropanol / nonanol mixture sequentially to a 100mL three-necked flask. Start stirring and allow the urea and cyclopropanol / nonanol mixture to fully dissolve at 50℃ and 0MPa to form a cycloalkanol solution of urea. Weigh 1g of the above-mentioned Guye No. 1 shale oil and add it to the prepared urea solution to form a mixture of shale oil and urea solution. Weigh 0.01g of ethylene-methyl acrylate copolymer (AC1210, produced by DuPont, USA, fractionated to obtain the desired molecular weight) with a weight average molecular weight of 150000g / mol and add it to the above mixture. Stir for 8 hours, then stop stirring and let stand for 24 hours to obtain a reaction mixture after urea dewaxing. By centrifugation, 0.21g of dewaxed liquid and 16.55g of urea inclusion complex solid were obtained. Calculate the single-stage yield of the dewaxing solution.

[0087] Examples 2-44

[0088] The results of the urea dewaxing experiments on shale oil are shown in Table 2. Example 41 used Guye No. 2 shale oil as the dewaxing feedstock, and Example 42 used Guye No. 3 shale oil as the dewaxing feedstock. The dewaxing conditions for the other examples were the same as in Example 1, except as given in the table.

[0089] Comparative Example

[0090] Using the shale oil from Example 1, without adding dewaxing aids, and with other experimental conditions the same as in Example 1, the dewaxing effect of the shale oil was investigated.

[0091] Table 2. Experimental Results of Main Conditions for Urea Dewaxing in Shale Oil

[0092]

[0093] Continued from Table 2

[0094]

[0095] Continued from Table 2

[0096]

[0097] Continued from Table 2

[0098]

[0099] Continued from Table 2

[0100]

[0101] As can be seen from Table 2, compared with the absence of dewaxing aids, the addition of ethylene-methyl acrylate copolymer with a specific molecular weight enables the wax molecules and urea to fit well together, which is beneficial to the aggregation of linear n-alkanes and their complexation with urea, thereby improving the separation efficiency of n-alkane wax and thus increasing the yield of dewaxing liquid.

[0102] (2) Separation of cycloalkane fractions

[0103] A certain amount of dewaxing solution rich in cycloalkanes and aromatics obtained from shale oil urea dewaxing was added to a 50mL three-necked flask. Stirring was started, and the temperature was increased. The temperature of the vessel, the outlet temperature, and the condensation temperature of the distillate were controlled respectively. Under certain pressure conditions, the light fraction rich in cycloalkanes with a temperature ≤200℃ in the dewaxing solution was distilled off, and the purity of the cycloalkanes was calculated.

[0104] Examples 43-48

[0105] The results of the cycloalkanes separation experiment are shown in Table 3. Except for the conditions given in Table 3, the results were the same as in Example 43. The single-stage separation yield of light cycloalkanes was calculated using the following method:

[0106] Single-stage yield of light cycloalkanes = (mass of cycloalkanes obtained from separation / mass of dewaxing solution) × 100%.

[0107] Table 3. Cycloalkanes Separation Conditions and Results

[0108]

[0109] As can be seen from the experimental results in Table 3, regardless of the composition of the dewaxing solution, as long as the appropriate process conditions are controlled, the separation of light cycloalkane distillate oil and heavy cycloalkane distillate oil in dewaxing solutions rich in cycloalkane and aromatic hydrocarbons can be achieved.

[0110] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for separating components in shale oil, characterized in that, The separation method includes: The lost-wax method is used to remove n-alkane wax from shale oil, yielding distillate oil containing cycloalkanes and aromatics; The distillate containing cycloalkanes and aromatics is cut to obtain cut shale oil; Purification operations are performed on the cut shale oil at temperatures below or equal to a set temperature to obtain fractions containing cycloalkanes and fractions containing aromatics.

2. The method according to claim 1, characterized in that, When the dewaxing method includes a dewaxing aid, the dewaxing aid is a mixture of low molecular weight ethylene-methyl acrylate copolymer with a weight average molecular weight of 10,000 g / mol to 100,000 g / mol and high molecular weight ethylene-methyl acrylate copolymer with a weight average molecular weight of 100,000 g / mol to 300,000 g / mol.

3. The method according to claim 2, characterized in that, The blending ratio of the low molecular weight ethylene-methyl acrylate copolymer and the high molecular weight ethylene-methyl acrylate copolymer is 1:10 to 10:

1.

4. The method according to any one of claims 1 to 3, characterized in that, When the lost-wax method includes an activator, the activator is selected from at least one of alcohol activators, ether activators, and deionized aqueous solutions.

5. The method according to claim 4, characterized in that, The activator is a liquid cycloalkanol having C3 to C10 carbon atoms, and / or the activator is an ion-free aqueous solution of a cycloalkanol having C3 to C10 carbon atoms, wherein the cycloalkanol in the liquid cycloalkanol, and / or the cycloalkanol in the ion-free aqueous solution of the cycloalkanol, is a mixture of at least two liquid cycloalkanols having C3 to C10 carbon atoms.

6. The method according to any one of claims 1 to 3, characterized in that, When the lost-wax method includes urea, solvent, and activator, and the solvent is selected from deionized aqueous solution, the activator is selected from cycloalkanol, and the mass ratio of urea to activator is 20:1 to 1:

1.

7. The method according to any one of claims 1 to 3, characterized in that, When the lost-wax method includes a solvent, the solvent is selected from at least one of alcohol solvents, ether solvents, and non-ionized aqueous solutions.

8. The method according to claim 7, characterized in that, The solvent is a liquid cycloalkanol having C3 to C10 carbon atoms, and / or the solvent is an ion-free aqueous solution of a cycloalkanol having C3 to C10 carbon atoms, wherein the cycloalkanol in the liquid cycloalkanol, and / or the cycloalkanol in the ion-free aqueous solution of the cycloalkanol, is a mixture of at least two or more liquid cycloalkanols having C3 to C10 carbon atoms.

9. The method according to any one of claims 1 to 3, characterized in that, The method employs a lost-wax extraction process to remove n-alkane wax from shale oil, yielding a distillate oil containing cycloalkanes and aromatics, including: A urea solution was prepared based on urea, solvent, and dewaxing agent, and the urea solution was heated to a set temperature. Add the first set amount of shale oil into the reaction vessel and maintain the set stirring speed; The second set amount of activator is added to the reaction vessel in batches; Set the reaction conditions for the complexation reaction so that the urea and the shale oil can undergo a complexation reaction; After the reaction vessel has been left to stand for a set time, a solid-liquid separation method is used to obtain a distillate oil containing cycloalkanes and aromatics.

10. A component separation system for shale oil, characterized in that, The separation system includes a removal system, a segmentation system, and a purification system, wherein, The removal system is used to remove n-alkane wax from shale oil using a lost-wax method to obtain distillate oil containing cycloalkanes and aromatics; The segmentation system is used to cut the distillate oil containing cycloalkanes and aromatics to obtain the cut shale oil; The purification system is used to perform purification operations on cut shale oil at temperatures below or equal to a set temperature to obtain fractions containing cycloalkanes and fractions containing aromatics.

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