阅读说明：本技术 一种中间相沥青的制备方法和制备系统 (Preparation method and preparation system of mesophase pitch ) 是由 武云 初人庆 方向晨 于 2020-05-15 设计创作，主要内容包括：本发明公开了一种中间相沥青的制备方法和制备系统,所述制备方法包括如下内容：(1)第1原料经加热后进入第一反应单元,反应后得到第1反应料流；(2)第2原料经加热后和第1反应料流进入第二反应单元,反应后得到第2反应料流；(3)第2反应料流快速降温后进入第三反应单元与载气接触进行处理,处理后得到油气产物和中间相沥青。所述制备系统包括加热单元,第一反应单元,第二反应单元,急冷装置,第三反应单元和分馏系统。所述中间相沥青的制备系统可以稳定长周期运转,而且通过上述制备方法得到的中间相沥青品质可控性好,收率高。(The invention discloses a preparation method and a preparation system of mesophase pitch, wherein the preparation method comprises the following steps: (1) heating the 1 st raw material, then feeding the heated raw material into a first reaction unit, and reacting to obtain a 1 st reaction material flow; (2) heating the 2 nd raw material and the 1 st reaction material flow to enter a second reaction unit, and reacting to obtain a 2 nd reaction material flow; (3) and (2) after the reaction material flow is rapidly cooled, the reaction material flow enters a third reaction unit to contact with carrier gas for treatment, and an oil gas product and mesophase pitch are obtained after treatment. The preparation system comprises a heating unit, a first reaction unit, a second reaction unit, a quenching device, a third reaction unit and a fractionation system. The preparation system of the mesophase pitch can stably run for a long period, and the mesophase pitch obtained by the preparation method has good quality controllability and high yield.)

1. A preparation method of mesophase pitch comprises the following steps:

(1) heating the 1 st raw material, then feeding the heated raw material into a first reaction unit, and reacting to obtain a 1 st reaction material flow;

(2) heating the 2 nd raw material and the 1 st reaction material flow to enter a second reaction unit, and reacting to obtain a 2 nd reaction material flow;

(3) and (2) after the reaction material flow is rapidly cooled, the reaction material flow enters a third reaction unit to be contacted with carrier gas for treatment, an oil gas product and mesophase pitch are obtained after the treatment, and gas, gasoline, diesel oil and circulating oil are obtained after the oil gas product is further fractionated.

2. A process for producing mesophase pitch according to claim 1, characterized in that: the 1 st raw material is a coal-series raw material and/or a petroleum-series raw material, wherein the coal-series raw material is one or more of coal tar, coal tar pitch and coal liquefaction residues, and quinoline insoluble substances are preferably removed from the coal-series raw material; the petroleum raw material is one or more of ethylene tar, catalytic cracking slurry oil, residual oil, petroleum asphalt and hydrogenated tail oil, and preferably the fraction with the boiling point of more than 350 ℃ obtained after the petroleum raw material is fractionated.

3. A process for producing mesophase pitch according to claim 1, characterized in that: the 2 nd raw material is aromatic oil, the aromatic hydrocarbon content is more than 70wt%, and the distillation range is 180-350 ℃.

4. A process for producing mesophase pitch according to claim 2, characterized in that: when the 1 st raw material is a coal-series raw material, the 2 nd raw material is wash oil and/or anthracene oil; when the 1 st raw material is a petroleum raw material, the 2 nd raw material is a fraction obtained by distilling the petroleum raw material and having a distillation range of 180-350 ℃.

5. A process for producing mesophase pitch according to claim 1, characterized in that: the 1 st raw material is a fraction of more than 350 ℃ obtained after the catalytic slurry oil is fractionated, and the 2 nd raw material is a fraction of 180-350 ℃ obtained after the catalytic slurry oil is fractionated.

6. A process for producing mesophase pitch according to claim 1, characterized in that: the mass ratio of the No. 2 raw material to the No. 1 raw material is 1: 10-3: 10, preferably 2: 10-3: 10.

7. a process for producing mesophase pitch according to claim 1, characterized in that: the operating conditions of the first reaction unit are as follows: the temperature is 420-480 ℃, and preferably 440-470 ℃; the pressure is normal pressure-5 MPa, and the retention time of the materials in the first reaction unit is 0.1-24 h, preferably 0.15-5 h.

8. A process for producing mesophase pitch according to claim 1, characterized in that: the operating conditions of the second reaction unit are as follows: the temperature is 380-420 ℃, and preferably 400-420 ℃; the pressure is normal pressure to 5MPa, and the retention time of the materials in the second reaction unit is 0.5 to 48 hours, preferably 10 to 48 hours.

9. A process for producing mesophase pitch according to claim 1, characterized in that: the operating temperature of the first reaction unit is 10-60 ℃ higher than that of the second reaction unit, the preferred operating temperature is 20-50 ℃, and the residence time of the materials in the first reaction unit is 0.05-47 hours, the preferred residence time of the materials in the second reaction unit is 2-40 hours shorter than that of the materials in the first reaction unit.

10. A process for producing mesophase pitch according to claim 1, characterized in that: the reaction effluent obtained by the second reaction unit enters a third reaction unit after being rapidly cooled, and the temperature after being rapidly cooled is reduced to 350-400 ℃, preferably 350-380 ℃; the cooling rate is 50 to 650 ℃/S, preferably 50 to 200 ℃/S.

11. A process for producing mesophase pitch according to claim 1, characterized in that: the 1 st raw material and the oil gas product from the third reaction unit exchange heat in the fractionating system, the raw material and circulating oil at the bottom of the fractionating system are pumped out from the bottom of the fractionating system after heat exchange, and the raw material and the circulating oil are further heated and then enter the first reaction unit for reaction.

12. A process for producing mesophase pitch according to claim 1, characterized in that: the operating conditions of the third reaction unit are as follows: the top pressure of the reactor is-0.5-1 MPa, preferably-0.3-0.5 MPa; the reaction temperature is 350-520 ℃, preferably 400-500 ℃, the residence time is 2-10h, preferably 3-5h, and the space velocity is 60-900L/(kg.h), preferably 90-300L/(kg.h).

13. A process for producing mesophase pitch according to claim 1, characterized in that: the carrier gas in the step (3) can be one or more of water vapor, nitrogen and inert gas, and is preferably water vapor or nitrogen; wherein the inert gas is one or more of helium, neon, argon, krypton and xenon.

14. A process for producing mesophase pitch according to claim 1, characterized in that: the circulation ratio of the circulating oil obtained in the fractionation system is controlled to be 0.5 to 1.5, preferably 0.5 to 1.0.

15. A process for producing mesophase pitch according to claim 1, characterized in that: the 10 percent distillation temperature of the circulating oil is 350-420 ℃, preferably 380-400 ℃, and the 90 percent distillation temperature is 450-520 ℃, preferably 480-500 ℃.

16. A process for producing mesophase pitch according to claim 1, characterized in that: the first reaction unit and the second reaction unit are both provided with at least 1 reactor, and the reactors are continuous reactors.

17. A process for producing mesophase pitch according to claim 1, characterized in that: the third reaction unit is provided with at least 1 reactor, and the reactor is a continuous reactor.

18. A preparation system of mesophase pitch comprises

A heating unit for receiving and heat-treating the 1 st raw material, the circulating oil and the 2 nd raw material;

the first reaction unit is used for receiving and processing the 1 st raw material and the circulating oil which are heated by the heating unit, and obtaining a 1 st reaction material flow after reaction;

the second reaction unit is used for receiving and processing the 2 nd raw material heated by the heating unit and the 1 st reaction material flow from the first reaction unit to obtain a 2 nd reaction material flow;

a quench apparatus for receiving and processing the 2 nd reaction effluent from the second reaction unit;

the third reaction unit is used for receiving and processing the 2 nd reaction effluent and the carrier gas which are processed by the quenching device, and obtaining an oil gas product and mesophase pitch after processing;

and the fractionation system is used for receiving the oil gas products and the raw materials from the third reaction unit and obtaining gas, gasoline, diesel oil and circulating oil after treatment.

19. A system for producing mesophase pitch according to claim 19, wherein: the heating unit comprises at least one heating furnace, preferably 2 heating furnaces, when 2 heating furnaces are arranged, the 1 st raw material and the circulating oil share 1 heating furnace, and the 2 nd raw material uses another heating furnace.

20. A system for producing mesophase pitch according to claim 19, wherein: the quenching device is one of a quenching boiler, a disc type oil quencher and a flue gas quencher, and the quenching boiler is preferably selected.

21. A system for producing mesophase pitch according to claim 19, wherein: the first reaction unit and the second reaction unit are both provided with at least 1 reactor, and the reactors are continuous reactors.

22. A system for producing mesophase pitch according to claim 19, wherein: the third reaction unit is provided with at least 1 reactor, and the reactor is a continuous reactor.

23. A mesophase pitch produced by the production process according to any one of claims 1 to 18.

24. The mesophase pitch of claim 24, wherein: the content of quinoline insoluble substances in the mesophase pitch is less than 20 wt%, the softening point is 220-280 ℃, the H/C is less than 0.6, and the mesophase morphology is a wide-area optical structure.

Technical Field

The invention relates to a preparation method and a preparation system of mesophase pitch.

Background

The mesophase pitch is a nematic liquid crystal obtained by using coal series, petroleum series, high molecular polymer and other aromatic compounds as raw materials through the means of thermal polycondensation, catalytic modification, hydrogenation modification, solvent extraction and the like, is a mixture consisting of a plurality of flat disc-shaped condensed ring aromatic hydrocarbons, and has optical anisotropy. Because the raw materials are wide in source and low in price, the mesophase pitch has the advantages of excellent performance, strong processability, high added value and the like, the mesophase pitch is known as a high-quality precursor of a plurality of carbon materials (such as high-modulus carbon fibers, needle coke, mesophase pitch-based foam carbon, electrode materials and the like), and the materials are widely applied to the fields of national defense, aerospace, civil industry and the like.

CN87103787 discloses a method for efficiently preparing uniform mesophase pitch, which is suitable for preparing the mesophase pitch for producing high-performance carbon fibers from coal tar or petroleum residue oil. The method comprises the steps of recovering asphalt with extremely low quinoline insoluble content through first-stage continuous heat treatment and distillation, performing second-stage continuous heat treatment in the presence of a hydrogen supply solvent, distilling and recovering hydrogenated asphalt, and performing heat treatment on the hydrogenated asphalt.

CN101525543A provides a preparation method of mesophase pitch, comprising the following steps: (1) mixing refined naphthalene, hydrogen fluoride and boron trifluoride according to the weight ratio of 10: 1-5: 2-6 mass ratio, and feeding into a polymerization kettle; (2) starting stirring, controlling the pressure to be 10-25 MPa and the temperature to be 150-200 ℃, and reacting for 4-6 hours; (3) and then raising the pressure to 25-30 MPa, raising the temperature to 260-310 ℃, and continuing to react for 4-6 hours to obtain the mesophase pitch.

CN105256409A discloses a mesophase pitch-based carbon fiber and a preparation method thereof, which prepares the mesophase pitch by mixing, heating and polymerizing coal pitch, petroleum pitch or aromatic hydrocarbon synthetic pitch with carbon nine fraction, polystyrene, tetrahydronaphthalene or ethylene tar pitch with a softening point of less than 60 ℃, and obtains the mesophase pitch-based carbon fiber by modification, viscosity reduction, centrifugal spinning, hot melt blowing and drawing, oxidation, carbonization and graphitization.

In summary, in the current mesophase pitch preparation process, one or a combination of several methods of thermal polycondensation, hydrogenation modification, catalytic modification and co-carbonization is adopted, and the process is complex. Or by batch operation, with low production efficiency, or by HF/BF₃As a catalyst, the catalyst has high corrosivity and is easy to corrode equipment; or the fractions with different properties are co-carbonized, and gas may appear after subsequent processing, carbonization and graphitization treatment because the combination condition of the additive and the raw material cannot be determinedDefects such as pores affect the spinnability of the mesophase pitch and the performance of the carbon fibers.

Disclosure of Invention

Aiming at the defects in the prior art, the invention mainly aims to provide a preparation method and a preparation system of mesophase pitch, wherein the preparation system of the mesophase pitch can be stably operated for a long period, and the obtained mesophase pitch has good quality controllability and high yield.

The invention provides a preparation method of mesophase pitch, which comprises the following steps:

(1) heating the 1 st raw material, then feeding the heated raw material into a first reaction unit, and reacting to obtain a 1 st reaction material flow;

(2) heating the 2 nd raw material and the 1 st reaction material flow to enter a second reaction unit, and reacting to obtain a 2 nd reaction material flow;

(3) and (2) after the reaction material flow is rapidly cooled, the reaction material flow enters a third reaction unit to be contacted with carrier gas for treatment, an oil gas product and mesophase pitch are obtained after the treatment, and gas, gasoline, diesel oil and circulating oil are obtained after the oil gas product is further fractionated.

In the above preparation method of mesophase pitch, the 1 st raw material may be a coal-based raw material and/or a petroleum-based raw material, wherein the coal-based raw material may be one or more of coal tar, coal tar pitch, and coal liquefaction residue, and preferably, the quinoline insoluble substances are removed from the coal-based raw material. The petroleum raw material can be one or more of ethylene tar, catalytic cracking slurry oil, residual oil, petroleum asphalt and hydrogenated tail oil, and is preferably a fraction with a boiling point of more than 350 ℃ obtained after the petroleum raw material is fractionated.

In the preparation method of the mesophase pitch, the 2 nd raw material is aromatic oil, the aromatic hydrocarbon content is more than 70wt%, the distillation range is 180-350 ℃, and when the 1 st raw material is a coal-series raw material, the 2 nd raw material is preferably wash oil and/or anthracene oil; when the 1 st raw material is a petroleum-based raw material, the 2 nd raw material is preferably a fraction having a distillation range of 180 to 350 ℃ obtained by distillation of the petroleum-based raw material.

In the preparation method of the mesophase pitch, it is further preferable that the 1 st raw material is a fraction of more than 350 ℃ obtained by fractionating the catalytic slurry oil, and the 2 nd raw material is a fraction of 180-350 ℃ obtained by fractionating the catalytic slurry oil.

In the preparation method of the mesophase pitch, the mass ratio of the No. 2 raw material to the No. 1 raw material is 1: 10-3: 10, preferably 2: 10-3: 10.

in the above preparation method of mesophase pitch, the operating conditions of the first reaction unit are as follows: the temperature is 420-480 ℃, and preferably 440-470 ℃; the pressure is normal pressure to 5MPa (gauge pressure), and the residence time of the materials in the first reaction unit is 0.1 to 24 hours, preferably 0.15 to 5 hours.

In the above preparation method of mesophase pitch, the operating conditions of the second reaction unit are as follows: the temperature is 380-420 ℃, and preferably 400-420 ℃; the pressure is normal pressure to 5MPa (gauge pressure), and the residence time of the materials in the second reaction unit is 0.5 to 48 hours, preferably 10 to 48 hours.

In the preparation method of the mesophase pitch, the operating temperature of the first reaction unit is 10-60 ℃ higher than that of the second reaction unit, preferably 20-50 ℃, and the retention time of the material in the first reaction unit is 0.05-47 h shorter than that of the material in the second reaction unit, preferably 2-40 h.

In the preparation method of the mesophase pitch, the reaction effluent obtained by the second reaction unit enters the third reaction unit after being rapidly cooled, and the temperature after being rapidly cooled is reduced to 350-400 ℃, preferably 350-380 ℃; the cooling rate is 50 to 650 ℃/S, preferably 50 to 200 ℃/S.

In the preparation method of the mesophase pitch, the 1 st raw material and the oil gas product from the third reaction unit are preferably subjected to heat exchange in a fractionation system, the raw material after heat exchange (the temperature of the raw material after heat exchange is controlled to be 200-250 ℃) and the circulating oil at the bottom of the fractionation system are pumped out from the bottom of the fractionation system, and the raw material is further heated to a specified temperature (the temperature of an outlet of a heating furnace is controlled to be 300-350 ℃) and then enters the first reaction unit for reaction.

In the above preparation method of mesophase pitch, the operating conditions of the third reaction unit are as follows: the top pressure of the reactor is-0.5-1 MPa (gauge pressure), preferably-0.3-0.5 MPa (gauge pressure), the reaction temperature is 350-520 ℃, preferably 400-500 ℃, the residence time is 2-10h, preferably 3-5h, and the space velocity is 60-900L/(kg.h), preferably 90-300L/(kg.h).

In the preparation method of the mesophase pitch, the carrier gas in the step (3) can be one or more of water vapor, nitrogen and inert gas, wherein the inert gas is one or more of helium, neon, argon, krypton and xenon; preferably steam or nitrogen.

In the above method for preparing mesophase pitch, the content of quinoline insoluble substances in the mesophase pitch product obtained from the third reaction unit is less than 30 wt%, preferably less than 20 wt%.

In the preparation method of the mesophase pitch, the circulation ratio of the circulating oil obtained in the fractionation system is controlled to be 0.5-1.5, preferably 0.5-1.0, and the circulation ratio is the mass ratio of the circulating oil to the raw material.

In the preparation method of the mesophase pitch, the 10 percent distillation temperature of the circulating oil is 350-420 ℃, preferably 380-400 ℃, and the 90 percent distillation temperature is 450-520 ℃, preferably 480-500 ℃.

In the above preparation method of mesophase pitch, the first reaction unit and the second reaction unit are both provided with at least 1 reactor, and the reactors are continuous reactors, which can be tubular reactors, which can also be continuous stirred tank reactors, and are preferably tubular reactors.

In the above preparation method of mesophase pitch, the third reaction unit is provided with at least 1 reactor, and the reactor may be a continuous reactor.

In a second aspect, the invention provides a system for preparing mesophase pitch, which comprises

A heating unit for receiving and heat-treating the 1 st raw material, the circulating oil and the 2 nd raw material;

the first reaction unit is used for receiving and processing the 1 st raw material and the circulating oil which are heated by the heating unit, and obtaining a 1 st reaction material flow after reaction;

the second reaction unit is used for receiving and processing the 2 nd raw material heated by the heating unit and the 1 st reaction material flow from the first reaction unit to obtain a 2 nd reaction material flow;

a quench apparatus for receiving and processing the 2 nd reaction effluent from the second reaction unit;

the third reaction unit is used for receiving and processing the 2 nd reaction effluent and the carrier gas which are processed by the quenching device, and obtaining an oil gas product and mesophase pitch after processing;

and the fractionation system is used for receiving the oil gas products and the raw materials from the third reaction unit and obtaining gas, gasoline, diesel oil and circulating oil after treatment.

In the above system for preparing mesophase pitch, the heating unit comprises at least one heating furnace, preferably 2 heating furnaces, and when 2 heating furnaces are provided, the 1 st material and the circulating oil share 1 heating furnace, and the 2 nd material uses another heating furnace. Specifically, when 2 heating furnaces are arranged, the 1 st heating furnace and the 2 nd heating furnace are respectively arranged, wherein the 1 st raw material and the circulating oil are heated by the 1 st heating furnace, and the 2 nd raw material is heated by the 2 nd heating furnace.

In the above-mentioned system for producing mesophase pitch, the quenching apparatus may be one of a quenching boiler, a tray oil quencher, a flue gas quencher, and the like, and is preferably a quenching boiler.

In the above system for preparing mesophase pitch, the first reaction unit and the second reaction unit are both provided with at least 1 reactor, and the reactors are continuous reactors, which may be tubular reactors, or continuous stirred tank reactors, preferably tubular reactors.

In the above system for preparing mesophase pitch, the third reaction unit is provided with at least 1 reactor, and the reactor is a continuous reactor.

In a third aspect, the invention provides a mesophase pitch prepared by the above process.

In the mesophase pitch, the content of quinoline insoluble substances is less than 20 wt%, the softening point is 220-280 ℃, the H/C is less than 0.6, and the mesophase form is a wide-area optical structure.

Compared with the prior art, the mesophase pitch preparation method and the mesophase pitch preparation system have the beneficial effects of:

1. in the preparation method of the mesophase pitch provided by the invention, the stable long-period operation of the whole production system is realized by comprehensively regulating and controlling the operating conditions of the first reaction unit, the second reaction unit, the quenching device and the third reaction unit, and the mesophase pitch with the softening point, the optical structure and other properties meeting the requirements is obtained. In particular, the first reaction unit, in which the temperature is higher than that of the second reaction unit but the residence time is shorter than that of the second reaction unit, ensures that a sufficient degree of thermal cracking reaction occurs in the first reaction unit while preventing excessive thermal polymerization, produces as many initial mesophase globules as possible in the first reaction unit, and then allows them to function as initiators as nuclei for mesophase formation in the subsequent mesophase formation process. The 2 nd raw material is introduced into the second reaction unit, and the reaction temperature of the second reaction unit is slightly lower than that of the first reaction unit, so that the viscosity of the system can be improved, the condensation reaction rate of macromolecular free radicals in the system is effectively reduced, and the carbonization reaction is alleviated, so that the viscosity of the system is prevented from being increased too fast, the fluidity of the system is improved, mesophase globules generated in the first reactor can be fused more fully, and the softening point and the optical structure of mesophase pitch are improved.

2. In the intermediate phase asphalt preparation system provided by the invention, the reaction product obtained by the second reaction unit is rapidly cooled in a very short time by additionally arranging the quenching device, so that the content of coke-like solids in the intermediate phase asphalt product can be greatly reduced, the quality of the intermediate phase asphalt is improved, and particularly the spinnability of the intermediate phase asphalt is improved.

3. In the preparation method of the mesophase pitch, the circulating oil obtained by the fractionation system is circulated to the reaction unit A, and because the circulating oil contains a certain amount of naphthenic ring condensed aromatic hydrocarbon, the thermal stability and rheological property of the system can be improved in the subsequent liquid phase carbonization process, and meanwhile, the yield of the mesophase pitch is improved.

4. The preparation method of the mesophase pitch provided by the invention is convenient for temperature control, flexible and controllable in process conditions, and can be used for continuously producing the mesophase pitch product with stable performance, wherein the mesophase pitch product has a wide-area optical structure, the softening point is 220-280 ℃, and the content of quinoline insoluble substances is less than 20 wt%.

Drawings

FIG. 1 is a schematic diagram of a system for producing mesophase pitch according to the present invention.

Detailed Description

The process of the present invention is described in further detail below with reference to the accompanying drawings and examples, but the following examples are not intended to limit the process of the present invention.

As shown in fig. 1, the present invention provides a system for preparing mesophase pitch, comprising the following components:

a first heating furnace 4 for receiving and heating the feedstock 1 and the cycle oil 3 from the fractionation system 2;

a first reaction unit 5 for receiving and processing the heated feedstock from the first heating furnace 4 to obtain a 1 st reaction stream 6;

a second furnace 10 for receiving and heating the 2 nd feedstock 9;

a second reaction unit 7 for receiving the heated 2 nd feedstock from the second heating furnace 10 and the 1 st reaction stream 6 from the first reaction unit to obtain a 2 nd reaction stream 8 after reaction;

a quench device 11 for receiving and processing the 2 nd reaction stream 8 from the second reaction unit 7, the 2 nd reaction stream 8 being obtained after rapid temperature reduction;

the third reaction unit 13 is used for receiving and processing the material 12 and the carrier gas 14 processed by the quenching device 11, under the action of the carrier gas 14, the material 12 is processed to obtain an oil gas product 15 and mesophase pitch 16, and the mesophase pitch 16 is taken as a product to be discharged from the device;

and the fractionating system 2 is used for receiving the oil gas product 15 and the raw material 1 from the third reaction unit 13, the raw material 1 and the oil gas product 15 exchange heat in the fractionating system, the oil gas product is fractionated to obtain gas 17, gasoline 18, diesel oil 19 and circulating oil 3, and the raw material 1 and the circulating oil 3 flow out of the fractionating system and enter the first heating furnace 4.

The 1 st raw material used in the embodiment and the comparative example of the invention is the fraction which is obtained by the reduced pressure distillation of oil slurry obtained by a certain refinery catalytic device and is higher than 350 ℃, and the 2 nd raw material is the 180 ℃ light fraction which is obtained by the reduced pressure distillation of the oil slurry, and the specific properties are shown in Table 1. The reaction conditions are shown in Table 2, and the reaction results are shown in Table 3.

TABLE 1 Properties of the raw materials

Example 1

Example 1 the production system shown in fig. 1 was used, the cooling rate of the quenching apparatus was 150 ℃/S, the properties of the raw materials are shown in table 1, the operating conditions are shown in table 2, and the reaction results are shown in table 3.

Example 2

Compared with example 1, the operation conditions are slightly different, the cooling rate of the quenching device is 180 ℃/S, the properties of the raw materials are shown in Table 1, the operation conditions are shown in Table 2, and the reaction results are shown in Table 3.

Comparative example 1

Compared with example 1, the method has no quenching device, the properties of the raw materials are shown in Table 1, the operating conditions are shown in Table 2, and the reaction results are shown in Table 3.

Comparative example 2

Compared with the example 2, the temperature of the first reaction unit is low, the temperature of the second reaction unit is high, the cooling rate of the quenching device is 150 ℃/S, the properties of raw materials are shown in a table 1, the operating conditions are shown in a table 2, and the reaction results are shown in a table 3.

TABLE 2 operating conditions

TABLE 3 reaction results and product Properties