CN118026798A - Method for synthesizing norbornene - Google Patents

Abstract

The invention discloses a method for synthesizing norbornene, which comprises the following steps: reacting dicyclopentadiene (DCPD) solution with ethylene in a reactor to prepare norbornene; wherein the reactor comprises a heat exchanger connected with the reactor, and the heat exchanger is used for condensing the steam of the organic solvent generated in the reaction and returning the steam to the reaction system. The method of the invention greatly reduces the reaction pressure to 40-80 bar under the premise of keeping higher conversion rate and selectivity of liquid phase reaction, improves the process safety, ensures that the highest conversion rate of dicyclopentadiene can reach 99.4%, ensures that the highest selectivity of norbornene can reach 98.3%, and ensures that the purity of the purified norbornene is more than or equal to 99%.

Description

A method for synthesizing norbornene

Technical Field

The invention belongs to the technical field of norbornene preparation, and relates to a method for synthesizing norbornene, and in particular to a method for synthesizing norbornene by adopting a coupled heat exchange kettle reactor.

Background technique

In the process of preparing ethylene by high-temperature cracking of petroleum hydrocarbons in the petrochemical industry, by-product _C5 fraction and _C9 fraction are obtained. Among them, (di)cyclopentadiene (DCPD) accounts for about 20% of the _C5 and _C9 fractions. Norbornene (NB) is an important high-value-added derivative product of (di)cyclopentadiene. It is a white, light-transmitting crystal at room temperature and easy to sublimate. It can be polymerized with ethylene to obtain cycloolefin copolymer (COC). COC resin is a material with broad application prospects, with extremely high transparency and excellent heat resistance, chemical stability, melt fluidity and dimensional stability. At present, COC has been widely used in the manufacture of various optical lens prisms, automobile headlights, optical films for liquid crystal displays (LCDs), contact lenses, electronic and electrical components, pharmaceutical and food packaging materials, etc.

Since norbornene derivatives have such a wide range of uses, the demand for norbornene has increased year by year, and its new production process has also received widespread attention. However, there are currently few companies that can mass-produce norbornene, so the study of cyclopentadiene, norbornene and its downstream products is of great significance to the upgrading of my country's petrochemical industry.

Norbornene is usually prepared in industry by Diels-Alder reaction with ethylene and dicyclopentadiene (DCPD) as raw materials. According to the different states of cyclopentadiene (CPD) or dicyclopentadiene (DCPD) under the operating conditions, the production process of norbornene and its derivatives can be divided into two types: liquid phase reaction process and gas phase reaction process. Among them, in the liquid phase reaction process, CPD or DCPD is in liquid state during the reaction process, and ethylene gas is dissolved in the liquid phase and then undergoes addition reaction; in the gas phase reaction process, CPD or DCPD is first heated to gasify it, and then mixed with ethylene and enters the reactor for reaction. Compared with the liquid phase reaction process, since the reactants and products of the gas phase reaction process are in the gas phase state, the molar volume is greatly increased. Due to the constraints of the reactor volume and processing capacity, the residence time of the gas phase process is greatly shortened compared with the liquid phase process. Although the reaction temperature is about 100°C higher than that of the liquid phase process, its final conversion rate is still relatively low, which restricts the application of such processes, and the high temperature, high pressure and strong heat release affect the safety and stability of the production process. At the same time, the existing process still has many problems such as polymers and ester compounds clogging pipelines and transportation.

Although the prior art has provided some methods for synthesizing norbornene from DCPD or CPD, in fact, such synthesis is very difficult to achieve in industry, because the reactivity of ethylene is low, and in order to improve the reactivity of ethylene, it is necessary to increase the reaction pressure and other operating conditions, which are very close to the explosive thermal decomposition conditions of CPD or DCPD, and are likely to cause equipment explosions during the synthesis of norbornene. Therefore, how to reduce the reaction pressure in the preparation of norbornene and achieve efficient and safe large-scale production is a technical problem that needs to be solved urgently.

Summary of the invention

In order to improve the above technical problems, the present invention provides a method for synthesizing norbornene, the method comprising the following steps:

(S1) reacting a dicyclopentadiene (DCPD) solution and ethylene in a reactor to prepare norbornene;

Wherein, the reactor includes a heat exchanger connected thereto, and the heat exchanger is used to condense the steam of the organic solvent generated in the reaction and return it to the reaction system.

According to an embodiment of the present invention, the reactor may also be referred to as a coupled heat exchange tank reactor, which comprises a reactor for containing dicyclopentadiene and ethylene for reaction, and a heat exchanger communicating with the reactor.

According to a preferred embodiment of the present invention, the temperature of the reactor is higher than the temperature of the heat exchanger.

According to an embodiment of the present invention, in step (S1), a dicyclopentadiene solution can be reacted with ethylene in a coupled heat exchange tank reactor to prepare norbornene.

According to an embodiment of the present invention, step (S1) may be performed in the presence of an organic solvent.

According to an embodiment of the present invention, the dicyclopentadiene solution refers to dicyclopentadiene dissolved in an organic solvent.

According to an embodiment of the present invention, the organic solvent is selected from solvents with large heat capacity, boiling point close to the reaction temperature, and suitable heat of vaporization, such as aromatic hydrocarbons or ketone solvents, preferably one, two or more of toluene, xylene or methyl isobutyl ketone.

According to an embodiment of the present invention, in step (S1), the molar ratio of dicyclopentadiene to the organic solvent may be (0.07-0.5):1, illustratively 0.077:1, 0.1:1, 0.174:1, 0.2:1, 0.3:1, 0.4:1, 0.5:1.

According to an embodiment of the present invention, in step (S1), the molar ratio of ethylene to dicyclopentadiene is 1:0.5 to 10:1, for example, 1:1, 2:1, 2.5:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1 or 10:1.

According to an embodiment of the present invention, in step (S1), the reaction temperature may be no more than 300°C, preferably no more than 280°C, more preferably 170-260°C, exemplarily 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C.

According to an embodiment of the present invention, in step (S1), the reaction time is more than 90 min, preferably 120 to 600 min, for example 120 min, 180 min, 200 min, 240 min, 300 min, 400 min, 500 min or 600 min.

According to an embodiment of the present invention, in step (S1), the reaction pressure is no more than 100 bar, preferably 40 to 80 bar, for example, 40 bar, 50 bar, 60 bar, 70 bar or 80 bar.

According to an embodiment of the present invention, the heat exchanger of the reactor is communicated with the upper part of the reaction kettle.

According to an embodiment of the present invention, in step (S1), the ethylene is fed from the bottom of the solution in the reactor.

According to an embodiment of the present invention, in step (S1), the heat exchanger includes a demister, a condenser and a liquid collector. Preferably, the demister, the condenser and the liquid collector are connected in sequence from top to bottom, and the heat exchanger and the liquid collector are connected to the upper part of the reactor.

According to an embodiment of the present invention, the dicyclopentadiene solution may be preheated before reacting with ethylene, and the preheating steps are as follows:

(S0) preheating a dicyclopentadiene (DCPD) solution, wherein the operating pressure of the preheater does not exceed 100 bar, and the outlet temperature of the preheated solution is 170-200°C.

In the present invention, by preheating the dicyclopentadiene solution, the heating load of the reactor can be reduced and the condensation heat of the organic solvent can be recovered.

According to an embodiment of the present invention, in step (S0), the molar ratio of dicyclopentadiene to the organic solvent is (0.07-0.5):1, for example, 0.077:1, 0.1:1, 0.174:1, 0.2:1, 0.3:1, 0.4:1, and 0.5:1, based on the molar number of dicyclopentadiene before preheating.

According to an embodiment of the present invention, in step (S0), the pressure during preheating is no more than 100 bar, preferably 40 to 80 bar, for example, 40 bar, 50 bar, 60 bar, 70 bar or 80 bar.

According to an embodiment of the present invention, in step (S0), the outlet temperature of the preheated solution is 170-200° C., illustratively 170° C., 180° C., 190° C., 200° C., 210° C., 220° C. According to an embodiment of the present invention, the preheated dicyclopentadiene (DCPD) solution also includes cyclopentadiene.

According to an embodiment of the present invention, step (S1) prepares a crude norbornene solution.

According to an embodiment of the present invention, the method further comprises the following steps:

(S2) purifying the crude norbornene solution prepared in step (S1) to obtain purified norbornene.

Preferably, the purification is performed by distillation, rectification or other methods known to those skilled in the art.

As an exemplary embodiment of the present invention, the method for synthesizing norbornene specifically comprises the following steps:

(1) preheating a solution of dicyclopentadiene in an organic solvent at a temperature of 170 to 200° C. and a pressure of 40 to 80 bar;

(2) passing the mixture obtained in step (1) into a coupled heat exchange tank reactor to react with ethylene passed into the bottom of the solution in the reactor to prepare a crude norbornene solution;

(3) distilling the crude norbornene solution obtained in step (2) to separate the unreacted raw materials, norbornene and the organic solvent to obtain purified norbornene.

According to an embodiment of the present invention, the reaction conversion rate of the method for synthesizing norbornene is ≥95%, preferably ≥99%.

According to an embodiment of the present invention, the norbornene selectivity of the method for synthesizing norbornene is ≥95%, preferably ≥98%.

According to an embodiment of the present invention, the purity of the purified norbornene is ≥99%.

The present invention also provides a coupled heat exchange kettle reactor, which comprises a reactor and a heat exchanger connected to the reactor.

According to an embodiment of the present invention, the coupled heat exchange tank reactor comprises a reactor for containing dicyclopentadiene and ethylene for reaction, and a heat exchanger connected to the reactor.

According to an embodiment of the present invention, the heat exchanger comprises a demister, a condenser and a liquid collector. Preferably, the demister, the condenser and the liquid collector are connected in sequence from top to bottom, and the heat exchanger and the liquid collector are connected to the upper part of the reactor.

According to an embodiment of the present invention, the reactor of the coupled heat exchange tank reactor contains one, two, three, four or five of dicyclopentadiene, cyclopentadiene, ethylene, norbornene and an organic solvent.

According to an embodiment of the present invention, the heat exchange kettle contains one, two or more of the organic solvents in gaseous and/or liquid form.

The present invention also provides a reaction device for preparing norbornene, wherein the reaction device comprises at least one set of coupled heat exchange kettle reactors.

According to an embodiment of the present invention, the number of the coupled heat exchange tank reactors is 2 to 4, preferably 2, and the multiple coupled heat exchange tank reactors are connected in series.

According to an embodiment of the present invention, the reaction device further comprises a feed pump and a preheater, and the feed pump, the preheater and the coupled heat exchange kettle reactor are connected in sequence.

According to an embodiment of the present invention, the reaction device further comprises a flash evaporator, and the flash evaporator is connected to the coupled heat exchange kettle reactor.

According to an embodiment of the present invention, the reaction device further comprises a lightness removal tower, and the lightness removal tower is connected to the discharge port of the flash evaporator.

According to an embodiment of the present invention, the reaction device further comprises a norbornene tower, and the norbornene tower is connected to the lightness removal tower.

According to an embodiment of the present invention, the reaction device further comprises a solvent recovery tower, and the solvent recovery tower is connected to the norbornene tower.

According to an embodiment of the present invention, the reaction device also includes an ethylene circulation tank, a circulation compressor, a raw gas compressor and an ethylene raw material tank; the ethylene raw material tank, the raw gas compressor, the ethylene circulation tank and the circulation compressor, and the coupled heat exchange kettle reactor are connected in sequence, and the ethylene circulation tank is also connected to the heat exchanger.

Beneficial Effects

The method of the present invention significantly reduces the reaction pressure to 40-80 bar while maintaining a high conversion rate and selectivity of a liquid phase reaction, thereby improving process safety. The conversion rate of dicyclopentadiene can reach up to 99.4%, the selectivity of norbornene can reach up to 98.3%, and the purity of the purified norbornene is ≥99%.

The present invention adopts a coupled heat exchange kettle reactor to recover reaction heat by evaporating and condensing an organic solvent, thereby solving the problems of difficulty in removing liquid phase reaction heat and ethylene transfer in the prior art norbornene synthesis process, reducing reaction pressure, ensuring safe operation, and effectively recovering reaction heat energy, so that the equipment can operate more safely and smoothly, maximizing the mass transfer advantages of the kettle reactor, and the process is simple and efficient.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart of an embodiment of a method for synthesizing norbornene according to the present invention.

FIG. 2 is a schematic diagram of a coupled heat exchange kettle reactor according to the present invention.

Among them: 1. batching tank; 2. feed pump; 3. preheater; 4. coupled heat exchange kettle reactor; 4a. reactor; 5. liquid collector; 6. condenser; 7. demister; 8. light removal tower; 9. norbornene tower; 10. solvent recovery tower; 11. flash evaporator; 12. ethylene circulation tank; 13. circulation compressor; 14. raw gas compressor; 15. ethylene raw material tank.

Detailed ways

The technical scheme of the present invention will be further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only exemplary descriptions and explanations of the present invention, and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are included in the scope that the present invention is intended to protect.

Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available or can be prepared by known methods.

Example 1

Figure 2 is a coupled heat exchange kettle reactor of the present invention, including a reactor body 4a and a heat exchanger, wherein the heat exchanger is located above the reactor 4a; the heat exchanger includes a demister 7, a condenser 6 and a liquid collector 5; the demister, condenser and liquid collector are connected in sequence from top to bottom, and the liquid collector is connected to the reactor body.

FIG1 is a process flow chart of the preparation of norbornene according to the present invention, as shown in FIG1 :

In a batching tank 1, dicyclopentadiene (DCPD) and toluene are configured into a solution at a molar ratio of 0.174:1. After entering a preheater 3 through a feed pump 2 to reach a preheating temperature of 200°C, they enter a group of two coupled heat exchange kettle reactors 4 in sequence. Ethylene is respectively introduced into the dicyclopentadiene toluene solutions of each coupled heat exchange kettle reactor (the coupled heat exchange kettle reactor is 5L) and reacts with dicyclopentadiene. The molar ratio of ethylene to DCPD is 2:1. The reaction time is 120min, the reaction temperature is 220°C, and the reaction pressure is 60bar. Under this condition, the dicyclopentadiene (DCPD) solution and ethylene generate a crude norbornene toluene solution. The coupled heat exchange kettle reactor recovers reaction heat by toluene evaporation and condensation by a condenser 6. The condensed toluene is collected by a liquid collector 5 and then sent back to the reactor 4a. Most of the unreacted ethylene passes through the condenser and then returns to the ethylene circulation tank 12 through a defoamer 7. It circulates into the reactor through a circulation compressor 13. Fresh ethylene enters the ethylene circulation tank after being pressurized by a compressor 14 to supplement the ethylene consumed by the reaction. After the crude norbornene toluene solution leaves the reactor, it enters the flash evaporator 11 to remove a small amount of ethylene therein. The operating pressure of the flash evaporator is atmospheric pressure. The ethylene returns to the ethylene circulation tank 12. After the crude norbornene toluene solution is de-ethyleneed, it enters the light component removal tower 8. The tower top temperature is 30°C and the operating pressure is 0.1 bar. The light component cyclopentadiene (CPD) is produced from the tower top. The norbornene toluene solution at the bottom of the tower enters the norbornene tower 9. The tower top temperature is 94.3°C and the operating pressure is 0.1 bar. Norbornene with a purity of ≥99% is produced at the tower top. The toluene at the bottom of the tower enters the solvent recovery tower 10. The tower top temperature is 110°C and the operating pressure is 0.1 bar. The toluene at the top of the tower is recovered to the liquid preparation tank for recycling, and the heavy component at the bottom of the tower is discharged from the device as a by-product.

Example 2

In a batching tank 1, dicyclopentadiene (DCPD) and toluene are configured into a solution at a molar ratio of 0.174:1. The solution first enters a preheater 3 through a feed pump 2 to reach a preheating temperature of 200°C, and then enters a group of two coupled heat exchange kettle reactors 4 in sequence. Ethylene is respectively introduced into the dicyclopentadiene toluene solutions of each coupled heat exchange kettle reactor to react with dicyclopentadiene. The molar ratio of ethylene to DCPD is 2:1. The reaction time is 180 minutes, the reaction temperature is 220°C, and the reaction pressure is 60 bar. Under this condition, the dicyclopentadiene (DCPD) solution and ethylene generate a crude norbornene toluene solution. The coupled heat exchange kettle reactor recovers reaction heat by toluene evaporation and condensation by a condenser 6. The condensed toluene is collected by a liquid collector 5 and then sent back to the reactor 4a. Most of the unreacted ethylene passes through the condenser and then returns to the ethylene circulation tank 12 through a defoamer 7. It circulates into the reactor through a circulation compressor 13. Fresh ethylene enters the ethylene circulation tank after being pressurized by a compressor 14 to supplement the ethylene consumed in the reaction. After the crude norbornene toluene solution leaves the reactor, it enters the flash evaporator 11 to remove a small amount of ethylene therein. The operating pressure of the flash evaporator is atmospheric pressure. The ethylene returns to the ethylene circulation tank 12. After the crude norbornene toluene solution is de-ethyleneed, it enters the light component removal tower 8. The tower top temperature is 30°C and the operating pressure is 0.1 bar. The light component CPD is produced from the tower top. The norbornene toluene solution at the bottom of the tower enters the norbornene tower 9. The tower top temperature is 94.3°C and the operating pressure is 0.1 bar. Norbornene with a purity of ≥99% is produced at the tower top. The toluene at the bottom of the tower enters the solvent recovery tower 10. The tower top temperature is 110°C and the operating pressure is 0.1 bar. The toluene at the top of the tower is recovered to the liquid preparation tank for recycling, and the heavy component at the bottom of the tower is discharged from the device as a by-product.

Example 3

In a batching tank 1, dicyclopentadiene (DCPD) and toluene are configured into a solution at a molar ratio of 0.174:1. After entering a preheater 3 through a feed pump 2 to reach a preheating temperature of 200°C, they enter a group of two coupled heat exchange kettle reactors 4 in sequence. Ethylene is respectively introduced into the dicyclopentadiene toluene solutions of each coupled heat exchange kettle reactor to react with dicyclopentadiene. The molar ratio of ethylene to DCPD is 2:1. The reaction time is 240 minutes, the reaction temperature is 220°C, and the reaction pressure is 60 bar. Under this condition, the dicyclopentadiene (DCPD) solution and ethylene generate a crude norbornene toluene solution. The coupled heat exchange kettle reactor recovers reaction heat by toluene evaporation and condensation by a condenser 6. The condensed toluene is collected by a liquid collector 5 and then sent back to the reactor 4a. Most of the unreacted ethylene passes through the condenser and then returns to the ethylene circulation tank 12 through a defoamer 7. It circulates into the reactor through a circulation compressor 13. Fresh ethylene enters the ethylene circulation tank after being pressurized by a compressor 14 to supplement the ethylene consumed in the reaction. After the crude norbornene toluene solution leaves the reactor, it enters the flash evaporator 11 to remove a small amount of ethylene therein. The operating pressure of the flash evaporator is atmospheric pressure. The ethylene returns to the ethylene circulation tank 12. After the crude norbornene toluene solution is de-ethyleneed, it enters the light component removal tower 8. The tower top temperature is 30°C and the operating pressure is 0.1 bar. The light component CPD is produced from the tower top. The norbornene toluene solution at the bottom of the tower enters the norbornene tower 9. The tower top temperature is 94.3°C and the operating pressure is 0.1 bar. Norbornene with a purity of ≥99% is produced at the tower top. The toluene at the bottom of the tower enters the solvent recovery tower 10. The tower top temperature is 110°C and the operating pressure is 0.1 bar. The toluene at the top of the tower is recovered to the liquid preparation tank for recycling, and the heavy component at the bottom of the tower is discharged from the device as a by-product.

Example 4

In a batching tank 1, dicyclopentadiene (DCPD) and toluene are configured into a solution at a molar ratio of 0.174:1. The solution first enters a preheater 3 through a feed pump 2 to reach a preheating temperature of 200°C, and then enters a group of two coupled heat exchange kettle reactors 4 in sequence. Ethylene is respectively introduced into the dicyclopentadiene toluene solutions of each coupled heat exchange kettle reactor to react with dicyclopentadiene. The molar ratio of ethylene to DCPD is 2:1. The reaction time is 360 minutes, the reaction temperature is 220°C, and the reaction pressure is 60 bar. Under this condition, the dicyclopentadiene (DCPD) solution and ethylene generate a crude norbornene toluene solution. The coupled heat exchange kettle reactor recovers the reaction heat by evaporating toluene and condensing with a condenser 6. The condensed toluene is collected by a liquid collector 5 and then sent back to the reactor 4a. Most of the unreacted ethylene passes through the condenser and then returns to the ethylene circulation tank 12 through a defoamer 7. It circulates into the reactor through a circulation compressor 13. Fresh ethylene enters the ethylene circulation tank after being pressurized by a compressor 14 to supplement the ethylene consumed in the reaction. After the crude norbornene toluene solution leaves the reactor, it enters the flash evaporator 11 to remove a small amount of ethylene therein. The operating pressure of the flash evaporator is atmospheric pressure. The ethylene returns to the ethylene circulation tank 12. After the crude norbornene toluene solution is de-ethyleneed, it enters the light component removal tower 8. The tower top temperature is 30°C and the operating pressure is 0.1 bar. The light component CPD is produced from the tower top. The norbornene toluene solution at the bottom of the tower enters the norbornene tower 9. The tower top temperature is 94.3°C and the operating pressure is 0.1 bar. Norbornene with a purity of ≥99% is produced at the tower top. The toluene at the bottom of the tower enters the solvent recovery tower 10. The tower top temperature is 110°C and the operating pressure is 0.1 bar. The toluene at the top of the tower is recovered to the liquid preparation tank for recycling, and the heavy component at the bottom of the tower is discharged from the device as a by-product.

Example 5

In a batching tank 1, dicyclopentadiene (DCPD) and toluene are configured into a solution at a molar ratio of 0.174:1. After entering a preheater 3 through a feed pump 2 to reach a preheating temperature of 200°C, they enter a group of two coupled heat exchange kettle reactors 4 in sequence. Ethylene is respectively introduced into the dicyclopentadiene toluene solutions of each coupled heat exchange kettle reactor to react with dicyclopentadiene. The molar ratio of ethylene to DCPD is 2:1. The reaction time is 480 minutes, the reaction temperature is 220°C, and the reaction pressure is 60 bar. Under this condition, the dicyclopentadiene (DCPD) solution and ethylene generate a crude norbornene toluene solution. The coupled heat exchange kettle reactor recovers reaction heat by toluene evaporation and condensation by a condenser 6. The condensed toluene is collected by a liquid collector 5 and then sent back to the reactor 4a. Most of the unreacted ethylene passes through the condenser and then returns to the ethylene circulation tank 12 through a defoamer 7. It circulates into the reactor through a circulation compressor 13. Fresh ethylene enters the ethylene circulation tank after being pressurized by a compressor 14 to supplement the ethylene consumed in the reaction. After the crude norbornene toluene solution leaves the reactor, it enters the flash evaporator 11 to remove a small amount of ethylene therein. The operating pressure of the flash evaporator is atmospheric pressure. The ethylene returns to the ethylene circulation tank 12. After the crude norbornene toluene solution is de-ethyleneed, it enters the light component removal tower 8. The tower top temperature is 30°C and the operating pressure is 0.1 bar. The light component CPD is produced from the tower top. The norbornene toluene solution at the bottom of the tower enters the norbornene tower 9. The tower top temperature is 94.3°C and the operating pressure is 0.1 bar. Norbornene with a purity of ≥99% is produced at the tower top. The toluene at the bottom of the tower enters the solvent recovery tower 10. The tower top temperature is 110°C and the operating pressure is 0.1 bar. The toluene at the top of the tower is recovered to the liquid preparation tank for recycling, and the heavy component at the bottom of the tower is discharged from the device as a by-product.

Example 6

In a batching tank 1, dicyclopentadiene (DCPD) and toluene are configured into a solution at a molar ratio of 0.174:1. The solution first enters a preheater 3 through a feed pump 2 to reach a preheating temperature of 180°C, and then enters a group of two coupled heat exchange kettle reactors 4 in sequence. Ethylene is respectively introduced into the dicyclopentadiene toluene solutions of each coupled heat exchange kettle reactor to react with dicyclopentadiene. The molar ratio of ethylene to DCPD is 2:1. The reaction time is 240 minutes, the reaction temperature is 180°C, and the reaction pressure is 40 bar. Under this condition, the dicyclopentadiene (DCPD) solution and ethylene generate a crude norbornene toluene solution. The coupled heat exchange kettle reactor recovers the reaction heat by evaporating toluene and condensing with a condenser 6. The condensed toluene is collected by a liquid collector 5 and then sent back to the reactor 4a. Most of the unreacted ethylene passes through the condenser and then returns to the ethylene circulation tank 12 through a defoamer 7. It circulates into the reactor through a circulation compressor 13. Fresh ethylene is pressurized by a compressor 14 and then enters the ethylene circulation tank to supplement the ethylene consumed in the reaction. After the crude norbornene toluene solution leaves the reactor, it enters the flash evaporator 11 to remove a small amount of ethylene therein. The operating pressure of the flash evaporator is atmospheric pressure. The ethylene returns to the ethylene circulation tank 12. After the crude norbornene toluene solution is de-ethyleneed, it enters the light component removal tower 8. The tower top temperature is 30°C and the operating pressure is 0.1 bar. The light component CPD is produced from the tower top. The norbornene toluene solution at the bottom of the tower enters the norbornene tower 9. The tower top temperature is 94.3°C and the operating pressure is 0.1 bar. Norbornene with a purity of ≥99% is produced at the tower top. The toluene at the bottom of the tower enters the solvent recovery tower 10. The tower top temperature is 110°C and the operating pressure is 0.1 bar. The toluene at the top of the tower is recovered to the liquid preparation tank for recycling, and the heavy component at the bottom of the tower is discharged from the device as a by-product.

Example 7

In a batching tank 1, dicyclopentadiene (DCPD) and toluene are configured into a solution at a molar ratio of 0.174:1. The solution first enters a preheater 3 through a feed pump 2 to reach a preheating temperature of 180°C, and then enters a group of two coupled heat exchange kettle reactors 4 in sequence. Ethylene is respectively introduced into the dicyclopentadiene toluene solutions of each coupled heat exchange kettle reactor to react with dicyclopentadiene. The molar ratio of ethylene to DCPD is 2:1. The reaction time is 240 minutes, the reaction temperature is 200°C, and the reaction pressure is 60 bar. Under this condition, the dicyclopentadiene (DCPD) solution and ethylene generate a crude norbornene toluene solution. The coupled heat exchange kettle reactor recovers the reaction heat by evaporating toluene and condensing with a condenser 6. The condensed toluene is collected by a liquid collector 5 and then sent back to the reactor 4a. Most of the unreacted ethylene passes through the condenser and then returns to the ethylene circulation tank 12 through a defoamer 7. It circulates into the reactor through a circulation compressor 13. Fresh ethylene enters the ethylene circulation tank after being pressurized by a compressor 14 to supplement the ethylene consumed in the reaction. After the crude norbornene toluene solution leaves the reactor, it enters the flash evaporator 11 to remove a small amount of ethylene therein. The operating pressure of the flash evaporator is atmospheric pressure. The ethylene returns to the ethylene circulation tank 12. After the crude norbornene toluene solution is de-ethyleneed, it enters the light component removal tower 8. The tower top temperature is 30°C and the operating pressure is 0.1 bar. The light component CPD is produced from the tower top. The norbornene toluene solution at the bottom of the tower enters the norbornene tower 9. The tower top temperature is 94.3°C and the operating pressure is 0.1 bar. Norbornene with a purity of ≥99% is produced at the tower top. The toluene at the bottom of the tower enters the solvent recovery tower 10. The tower top temperature is 110°C and the operating pressure is 0.1 bar. The toluene at the top of the tower is recovered to the liquid preparation tank for recycling, and the heavy component at the bottom of the tower is discharged from the device as a by-product.

Example 8

In a batching tank 1, dicyclopentadiene (DCPD) and toluene are configured into a solution at a molar ratio of 0.174:1. The solution first enters a preheater 3 through a feed pump 2 to reach a preheating temperature of 200°C, and then enters a group of two coupled heat exchange kettle reactors 4 in sequence. Ethylene is respectively introduced into the dicyclopentadiene toluene solutions of each coupled heat exchange kettle reactor to react with dicyclopentadiene. The molar ratio of ethylene to DCPD is 2:1. The reaction time is 240 minutes, the reaction temperature is 240°C, and the reaction pressure is 60 bar. Under this condition, the dicyclopentadiene (DCPD) solution and ethylene generate a crude norbornene toluene solution. The coupled heat exchange kettle reactor recovers the reaction heat by evaporating toluene and condensing with a condenser 6. The condensed toluene is collected by a liquid collector 5 and then sent back to the reactor 4a. Most of the unreacted ethylene passes through the condenser and then returns to the ethylene circulation tank 12 through a defoamer 7. It circulates into the reactor through a circulation compressor 13. Fresh ethylene is pressurized by a compressor 14 and then enters the ethylene circulation tank to supplement the ethylene consumed in the reaction. After the crude norbornene toluene solution leaves the reactor, it enters the flash evaporator 11 to remove a small amount of ethylene therein. The operating pressure of the flash evaporator is atmospheric pressure. The ethylene returns to the ethylene circulation tank 12. After the crude norbornene toluene solution is de-ethyleneed, it enters the light component removal tower 8. The tower top temperature is 30°C and the operating pressure is 0.1 bar. The light component CPD is produced from the tower top. The norbornene toluene solution at the bottom of the tower enters the norbornene tower 9. The tower top temperature is 94.3°C and the operating pressure is 0.1 bar. Norbornene with a purity of ≥99% is produced at the tower top. The toluene at the bottom of the tower enters the solvent recovery tower 10. The tower top temperature is 110°C and the operating pressure is 0.1 bar. The toluene at the top of the tower is recovered to the liquid preparation tank for recycling, and the heavy component at the bottom of the tower is discharged from the device as a by-product.

Example 9

In a batching tank 1, dicyclopentadiene (DCPD) and toluene are configured into a solution at a molar ratio of 0.08:1. The solution first enters a preheater 3 through a feed pump 2 to reach a preheating temperature of 200° C., and then enters a group of two coupled heat exchange kettle reactors 4 in sequence. Ethylene is respectively introduced into the dicyclopentadiene toluene solutions of each coupled heat exchange kettle reactor to react with dicyclopentadiene. The molar ratio of ethylene to DCPD is 2:1. The reaction time is 480 min, the reaction temperature is 220° C., and the reaction pressure is 50 bar. Under this condition, the dicyclopentadiene (DCPD) solution and ethylene generate a crude norbornene toluene solution. The coupled heat exchange kettle reactor recovers reaction heat by toluene evaporation and condensation by a condenser 6. The condensed toluene is collected by a liquid collector 5 and then sent back to the reactor 4a. Most of the unreacted ethylene passes through the condenser and then returns to the ethylene circulation tank 12 through a defoamer 7. It circulates into the reactor through a circulation compressor 13. Fresh ethylene enters the ethylene circulation tank after being pressurized by a compressor 14 to supplement the ethylene consumed in the reaction. After the crude norbornene toluene solution leaves the reactor, it enters the flash evaporator 11 to remove a small amount of ethylene therein. The operating pressure of the flash evaporator is atmospheric pressure. The ethylene returns to the ethylene circulation tank 12. After the crude norbornene toluene solution is de-ethyleneed, it enters the light component removal tower 8. The tower top temperature is 30°C and the operating pressure is 0.1 bar. The light component CPD is produced from the tower top. The norbornene toluene solution at the bottom of the tower enters the norbornene tower 9. The tower top temperature is 94.3°C and the operating pressure is 0.1 bar. Norbornene with a purity of ≥99% is produced at the tower top. The toluene at the bottom of the tower enters the solvent recovery tower 10. The tower top temperature is 110°C and the operating pressure is 0.1 bar. The toluene at the top of the tower is recovered to the liquid preparation tank for recycling, and the heavy component at the bottom of the tower is discharged from the device as a by-product.

Example 10

In a batching tank 1, dicyclopentadiene (DCPD) and toluene are configured into a solution at a molar ratio of 0.08:1. The solution first enters a preheater 3 through a feed pump 2 to reach a preheating temperature of 200° C., and then enters a group of two coupled heat exchange kettle reactors 4 in sequence. Ethylene is respectively introduced into the dicyclopentadiene toluene solutions of each coupled heat exchange kettle reactor to react with dicyclopentadiene. The molar ratio of ethylene to DCPD is 2:1. The reaction time is 240 min, the reaction temperature is 220° C., and the reaction pressure is 60 bar. Under this condition, the dicyclopentadiene (DCPD) solution and ethylene generate a crude norbornene toluene solution. The coupled heat exchange kettle reactor recovers the reaction heat by evaporating toluene and condensing with a condenser 6. The condensed toluene is collected by a liquid collector 5 and then sent back to the reactor 4a. Most of the unreacted ethylene passes through the condenser and then returns to the ethylene circulation tank 12 through a defoamer 7. It circulates into the reactor through a circulation compressor 13. Fresh ethylene is pressurized by a compressor 14 and then enters the ethylene circulation tank to supplement the ethylene consumed in the reaction. After the crude norbornene toluene solution leaves the reactor, it enters the flash evaporator 11 to remove a small amount of ethylene therein. The operating pressure of the flash evaporator is atmospheric pressure. The ethylene returns to the ethylene circulation tank 12. After the crude norbornene toluene solution is de-ethyleneed, it enters the light component removal tower 8. The tower top temperature is 30°C and the operating pressure is 0.1 bar. The light component CPD is produced from the tower top. The norbornene toluene solution at the bottom of the tower enters the norbornene tower 9. The tower top temperature is 94.3°C and the operating pressure is 0.1 bar. Norbornene with a purity of ≥99% is produced at the tower top. The toluene at the bottom of the tower enters the solvent recovery tower 10. The tower top temperature is 110°C and the operating pressure is 0.1 bar. The toluene at the top of the tower is recovered to the liquid preparation tank for recycling, and the heavy component at the bottom of the tower is discharged from the device as a by-product.

Embodiment 11

In a batching tank 1, dicyclopentadiene (DCPD) and toluene are configured into a solution at a molar ratio of 0.3:1. The solution first enters a preheater 3 through a feed pump 2 to reach a preheating temperature of 200°C, and then enters a group of two coupled heat exchange kettle reactors 4 in sequence. Ethylene is respectively introduced into the dicyclopentadiene toluene solutions of each coupled heat exchange kettle reactor to react with dicyclopentadiene. The molar ratio of ethylene to DCPD is 2:1. The reaction time is 240 minutes, the reaction temperature is 220°C, and the reaction pressure is 50 bar. Under this condition, the dicyclopentadiene (DCPD) solution and ethylene generate a crude norbornene toluene solution. The coupled heat exchange kettle reactor recovers reaction heat by toluene evaporation and condensation by a condenser 6. The condensed toluene is collected by a liquid collector 5 and then sent back to the reactor 4a. Most of the unreacted ethylene passes through the condenser and then returns to the ethylene circulation tank 12 through a defoamer 7. It circulates into the reactor through a circulation compressor 13. Fresh ethylene enters the ethylene circulation tank after being pressurized by a compressor 14 to supplement the ethylene consumed in the reaction. After the crude norbornene toluene solution leaves the reactor, it enters the flash evaporator 11 to remove a small amount of ethylene therein. The operating pressure of the flash evaporator is atmospheric pressure. The ethylene returns to the ethylene circulation tank 12. After the crude norbornene toluene solution is de-ethyleneed, it enters the light component removal tower 8. The tower top temperature is 30°C and the operating pressure is 0.1 bar. The light component CPD is produced from the tower top. The norbornene toluene solution at the bottom of the tower enters the norbornene tower 9. The tower top temperature is 94.3°C and the operating pressure is 0.1 bar. Norbornene with a purity of ≥99% is produced at the tower top. The toluene at the bottom of the tower enters the solvent recovery tower 10. The tower top temperature is 110°C and the operating pressure is 0.1 bar. The toluene at the top of the tower is recovered to the liquid preparation tank for recycling, and the heavy component at the bottom of the tower is discharged from the device as a by-product.

Example 12

In a batching tank 1, dicyclopentadiene (DCPD) and methyl isobutyl ketone are prepared into a solution at a molar ratio of 0.3:1. After entering a preheater 2 through a feed pump 2 to reach a preheating temperature of 200°C, they enter a group of two coupled heat exchange reactors 4 in sequence. Ethylene is respectively introduced into the dicyclopentadiene methyl isobutyl ketone solutions of each coupled heat exchange reactor to react with dicyclopentadiene. The molar ratio of ethylene to DCPD is 2:1. The reaction time is 240 min, the reaction temperature is 220°C, and the reaction pressure is 50 b ar, dicyclopentadiene (DCPD) solution and ethylene generate crude norbornene methyl isobutyl ketone solution under this condition, and the reaction heat is recovered by evaporating methyl isobutyl ketone and condensing by condenser 6 in a coupled heat exchange kettle reactor, and the condensed methyl isobutyl ketone is collected by a liquid collector 5 and then sent back to the reactor 4a, and most of the unreacted ethylene passes through the condenser and then returns to the ethylene circulation tank 12 through the demister 7, and then circulates into the reactor through the circulation compressor 13, and the fresh ethylene enters the ethylene circulation tank after being pressurized by the compressor 14 to supplement the ethylene consumed in the reaction. After the crude norbornene methyl isobutyl ketone solution leaves the reactor, it enters the flash evaporator 11 to remove a small amount of ethylene therein. The operating pressure of the flash evaporator is atmospheric pressure. The ethylene returns to the ethylene circulation tank 12. After the crude norbornene methyl isobutyl ketone solution is de-ethyleneed, it enters the light component removal tower 8. The tower top temperature is 30°C and the operating pressure is 0.1 bar. The light component CPD is produced from the tower top. The norbornene methyl isobutyl ketone solution at the bottom of the tower enters the norbornene tower 9. The tower top temperature is 94.3°C and the operating pressure is 0.1 bar. Norbornene with a purity of ≥99% is produced at the tower top. The methyl isobutyl ketone in the bottom of the tower enters the solvent recovery tower 10. The tower top temperature is 116.5°C and the operating pressure is 0.1 bar. The methyl isobutyl ketone at the top of the tower is recovered to the liquid preparation tank for recycling, and the heavy component at the bottom of the tower is discharged from the device as a by-product.

Example 13

In a batching tank 1, dicyclopentadiene (DCPD) and xylene are configured into a solution at a molar ratio of 0.174:1. After entering a preheater 3 through a feed pump 2 to reach a preheating temperature of 200°C, they enter a group of two coupled heat exchange kettle reactors 4 in sequence. Ethylene is respectively introduced into the dicyclopentadiene xylene solutions of each coupled heat exchange kettle reactor to react with dicyclopentadiene. The molar ratio of ethylene to DCPD is 2:1. The reaction time is 240 minutes, the reaction temperature is 220°C, and the reaction pressure is 50 bar. Under this condition, the dicyclopentadiene (DCPD) solution and ethylene generate a crude norbornene xylene solution. The coupled heat exchange kettle reactor recovers reaction heat by evaporating xylene and condensing it in a condenser 6. The condensed xylene is collected by a liquid collector 4 and then sent back to the reactor 4a. Most of the unreacted ethylene passes through the condenser and then returns to the ethylene circulation tank 12 through a defoamer 7. It circulates into the reactor through a circulation compressor 13. Fresh ethylene enters the ethylene circulation tank after being pressurized by a compressor 14 to supplement the ethylene consumed in the reaction. After the crude norbornene xylene solution leaves the reactor, it enters the flash evaporator 11 to remove a small amount of ethylene therein. The operating pressure of the flash evaporator is atmospheric pressure. The ethylene returns to the ethylene circulation tank 12. After the crude norbornene xylene solution is de-ethyleneed, it enters the light component removal tower 8. The tower top temperature is 30°C and the operating pressure is 0.1 bar. The light component CPD is produced from the tower top. The norbornene xylene solution at the bottom of the tower enters the norbornene tower 9. The tower top temperature is 94.3°C and the operating pressure is 0.1 bar. Norbornene with a purity of ≥99% is produced at the tower top. The xylene at the bottom of the tower enters the solvent recovery tower 10. The tower top temperature is 137°C and the operating pressure is 0.1 bar. The xylene at the top of the tower is recovered to the liquid preparation tank for recycling, and the heavy component at the bottom of the tower is discharged from the device as a by-product.

The norbornene prepared in Example 1-13 was analyzed by gas chromatography (GC) (peak area normalization method), and the purity of the norbornene product was ≥99%;

GC setting conditions: HP-1 chromatographic column, the initial temperature of the column oven is set at 70°C during the heating process, maintained for 2 minutes, and then heated to 220°C at a heating rate of 10°C/min, and the constant temperature is maintained for 5 minutes; the injection port temperature is 220°C. The injection volume is 0.5μL, the carrier gas flow rate is 1ml/min, the split ratio is 100:1, the air flow rate is 350ml/min, the hydrogen flow rate is 35ml/min, and a hydrogen flame ionization detector is used.

The DCPD conversion rate is the molar amount of DCPD consumed after the reaction divided by the molar amount of DCPD input before the reaction, and the NB selectivity is the molar amount of DCPD converted into the target product NB divided by the molar amount of DCPD consumed.

The test results are shown in Table 2 below.

The reaction conditions in the coupled heat exchange kettle reactor in Examples 1-13 are shown in Table 1 below:

Table 1

DCPD/Solvent Molar Ratio Reaction time temperature reflex Reaction pressure Example 1 0.174:1 2h 220℃ 60bar Example 2 0.174:1 3h 220℃ 60bar Example 3 0.174:1 4h 220℃ 60bar Example 4 0.174:1 6h 220℃ 60bar Example 5 0.174:1 8h 220℃ 60bar Example 6 0.174:1 4h 180℃ 40bar Example 7 0.174:1 4h 200℃ 60bar Example 8 0.174:1 4h 240℃ 60bar Example 9 0.08:1 8h 220℃ 50bar Example 10 0.08:1 4h 220℃ 60bar Embodiment 11 0.3:1 4h 220℃ 50bar Example 12 0.3:1 4h 220℃ 50bar Example 13 0.174:1 4h 220℃ 50bar

Table 2

The above is an exemplary description of the embodiments of the present invention. However, the protection scope of the present invention is not limited to the above embodiments. Any modification, equivalent substitution, improvement, etc. made by those skilled in the art within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims (10)

1. A method for synthesizing norbornene, characterized in that the method comprises the following steps: (S1) reacting a dicyclopentadiene (DCPD) solution and ethylene in a reactor to prepare norbornene; Wherein, the reactor includes a heat exchanger connected thereto, and the heat exchanger is used to condense the steam of the organic solvent generated in the reaction and return it to the reaction system. 2. The method according to claim 1 is characterized in that the reactor is also called a coupled heat exchange tank reactor, which includes a reactor for accommodating dicyclopentadiene and ethylene for reaction, and a heat exchanger connected to the reactor. 3. The method according to claim 1 or 2, wherein the dicyclopentadiene solution refers to dicyclopentadiene dissolved in an organic solvent. Preferably, the organic solvent is selected from solvents with suitable boiling points and heat of vaporization, such as aromatic hydrocarbons or ketone solvents, preferably one, two or more of toluene, xylene or methyl isobutyl ketone. Preferably, in step (S1), the molar ratio of dicyclopentadiene to the organic solvent is (0.07-0.5):1. Preferably, in step (S1), the molar ratio of ethylene to dicyclopentadiene is 1:0.5 to 10:1. Preferably, in step (S1), the reaction temperature may be no higher than 300°C; and the reaction pressure may be no higher than 100 bar. 4. The method according to any one of claims 1 to 3, characterized in that the heat exchanger of the reactor is connected to the upper part of the reaction kettle. 5. The method according to any one of claims 1 to 4, characterized in that in step (S1), the heat exchanger comprises a demister, a condenser and a liquid collector. Preferably, the demister, the condenser and the liquid collector are connected in sequence from top to bottom, and the heat exchanger and the liquid collector are connected to the upper part of the reactor. 6. The method according to any one of claims 1 to 5, characterized in that the dicyclopentadiene solution is preheated before reacting with ethylene, and the preheating step is: (S0) preheating the dicyclopentadiene solution, the operating pressure of the preheater does not exceed 100 bar, and the outlet temperature of the preheated solution is 170-200°C. 7. A coupled heat exchange kettle reactor, characterized in that it comprises a reactor and a heat exchanger connected to the reactor. Preferably, the coupled heat exchange tank reactor comprises a reactor for accommodating dicyclopentadiene and ethylene for reaction, and a heat exchanger connected to the reactor. Preferably, the heat exchanger comprises a demister, a condenser and a liquid collector. Preferably, the demister, the condenser and the liquid collector are connected in sequence from top to bottom, and the heat exchanger and the liquid collector are connected to the upper part of the reactor. Preferably, the reactor of the coupled heat exchange tank reactor contains one, two, three, four or five of dicyclopentadiene, cyclopentadiene, ethylene, norbornene and an organic solvent. 8. A reaction device for preparing norbornene, characterized in that the reaction device comprises at least one set of coupled heat exchange kettle reactors according to claim 7. 9. The reaction device according to claim 8 is characterized in that the reaction device also includes a feed pump and a preheater, and the feed pump, preheater and coupled heat exchange kettle reactor are connected in sequence. Preferably, the reaction device further comprises a flash evaporator, and the flash evaporator is connected to the coupled heat exchange kettle reactor. Preferably, the reaction device further comprises a lightness removal tower, and the lightness removal tower is connected to the discharge port of the flash evaporator. 10 . The reaction device according to claim 8 or 9 , characterized in that the reaction device further comprises a norbornene tower, and the norbornene tower is connected to the lightness removal tower. Preferably, the reaction device further comprises a solvent recovery tower, and the solvent recovery tower is connected to the norbornene tower. Preferably, the reaction device also includes an ethylene circulation tank, a circulation compressor, a raw gas compressor and an ethylene raw material tank; the ethylene raw material tank, the raw gas compressor, the ethylene circulation tank and the circulation compressor, and the coupled heat exchange kettle reactor are connected in sequence, and the ethylene circulation tank is also connected to the heat exchanger.