Process and apparatus for the production of cyclopentadiene monomer

Abstract

The application relates to the chemical technology field, in particular to a preparation method and device of a cyclopentadiene monomer. The method comprises the following steps: S1, heating dicyclopentadiene to 160-180 DEG C, and cracking and gasifying the dicyclopentadiene into cyclopentadiene under the stirring state; S2, collecting the crude cyclopentadiene in a rectifying tower filled with internal packing, keeping the tower top temperature at 40-42 DEG C, and keeping the pressure at-5kPa-0kPa; S3, cooling the collected material to-25--10 DEG C by using a refrigerant. The device comprises a reaction kettle, a rectifying tower and a collecting tank which are sequentially connected, and a condenser is arranged on the rectifying tower. Nitrogen and vacuum control pipelines are arranged on the condenser. The application mainly aims at the characteristics that the cyclopentadiene monomer is easy to polymerize, and has the advantages of simple equipment and operation, high yield and high purity.

Description

Technical Field

[0001] This application belongs to the field of chemical technology, specifically relating to a method and apparatus for preparing cyclopentadiene monomer. Background Technology

[0002] Cyclopentadiene is a basic organic monomer feedstock. It rapidly polymerizes at room temperature to form a dimer, requiring the pyrolysis of dicyclopentadiene into monomers before use. The reaction formula is as follows: C 10 H 12 = 2C5H6 The boiling points of cyclopentadiene (42℃) and the impurity dicyclopentadiene (170℃) differ significantly, but conventional distillation separation processes often generate polymers, such as cyclopentadiene trimers and tetramers, leading to reduced yields. If these polymers accumulate in large quantities in the reactor, they will form large amounts of high-molecular-weight solid polymers, clogging the equipment. This is because the cyclopentadiene monomer is a diene and can undergo a Diels-Alder reaction with the monoene dicyclopentadiene to form cyclic polymers, as shown below: C5H6+ C 10 H 12 = C 15 H 18 + C 20 H 24 + ...... Therefore, how to promote the removal of diene cyclopentadiene from the reaction system during the purification process, effectively reduce the formation of by-products, and improve the reaction yield has become an urgent problem to be solved. Summary of the Invention

[0003] To properly address polymerization side reactions and improve reaction yield, this application provides a method and apparatus for preparing cyclopentadiene monomers. By optimizing the separation method, high-purity and high-yield cyclopentadiene synthesis is achieved.

[0004] The technical solution adopted in this application is as follows: A method for preparing a cyclopentadiene monomer includes the following steps: S1. Dicyclopentadiene is heated to 160~180℃ and cracked and vaporized into crude cyclopentadiene under stirring. S2 and crude cyclopentadiene are fed into a packed distillation column for separation, and the column top temperature is maintained at 40~42℃ and the pressure is -5kPa~-1kPa for collection. S3. Use refrigerant to cool down to -25~-10℃ and collect the material.

[0005] Preferably, the heating method in step S1 is jacket heating or electric heating, and the stirring rate is 120~150 rpm.

[0006] Preferably, the packing material in step S2 is a macroporous packing material.

[0007] Preferably, the metal wire mesh aperture of the macroporous filler in step S2 is not less than 50 mesh.

[0008] Preferably, the packing material in step S2 is θ-ring packing.

[0009] Preferably, the diameter of the θ-ring packing ring in step S2 is not less than 4×4 mm.

[0010] Preferably, the number of theoretical plates in the distillation column in step S2 is 10 to 30.

[0011] An apparatus for preparing cyclopentadiene monomer includes a reaction vessel, a distillation column, and a collection tank connected sequentially by pipelines. A condenser is installed between the distillation column and the collection tank. Both the condenser and the collection tank are connected to nitrogen control lines and vacuum control lines, respectively. Pressure gauges are installed on the nitrogen control lines and vacuum control lines. A sampling port is installed on the pipeline between the condenser and the collection tank. The material collected by the condenser is not refluxed.

[0012] Preferably, the reactor is made of stainless steel, titanium or nickel, and is provided with a feed inlet and a residue discharge outlet. A first stirring device is provided inside the reactor, and a first jacket is provided on the outer wall of the reactor. Heat transfer oil flows through the first jacket, and the first jacket is provided with a heat transfer oil inlet and a heat transfer oil outlet.

[0013] Preferably, the collecting tank is made of stainless steel, quartz, titanium or nickel, and has a second jacket through which refrigerant flows. The second jacket is provided with a refrigerant inlet and a refrigerant outlet. The collecting tank is also provided with a condensate inlet and a discharge outlet, and a second stirring device is provided inside the collecting tank.

[0014] The distillation column is filled with macroporous packing material, with a theoretical plate number of 10 to 30. It directly dissipates heat and cools the external environment, and the liquid in the condenser is directly collected in a collection tank.

[0015] By adopting the above technical solution, the equipment in this application is simple to operate and achieves the synthesis of high-purity, high-yield cyclopentadiene. Gas chromatography analysis shows that the cyclopentadiene monomer content can reach over 97%, and the yield exceeds 80%.

[0016] This application includes at least one of the following beneficial technical effects: 1. The product has high purity and requires no further purification.

[0017] 2. Reduce the formation of polymerization byproducts and increase yield. Attached Figure Description

[0018] Figure 1This is a schematic diagram of the device structure of the present invention; In the figure, 1-reaction vessel, 11-feed inlet, 12-residue discharge outlet, 13-first stirring device, 14-heat transfer oil inlet, 15-heat transfer oil outlet, 16-first jacket; Distillation column; Condenser; 41 - Nitrogen control line; 42 - Vacuum control line; 5-Collection tank, 51-Refrigerant inlet, 52-Refrigerant outlet, 53-Condensate inlet, 54-Second stirring device, 55-Second jacket, 56-Discharge outlet; 6-Sampling port. Detailed Implementation

[0019] The present application will be further described in detail below with reference to the accompanying drawings.

[0020] Device Examples Reference Figure 1 An apparatus for preparing cyclopentadiene monomer includes a reaction vessel 1, a distillation column 2, and a collection tank 5 connected sequentially by pipelines. A condenser 3 is installed between the distillation column 2 and the collection tank 5. Both the condenser 3 and the collection tank 5 are connected to a nitrogen control line 41 and a vacuum control line 42, respectively. Pressure gauges are installed on the nitrogen control line 41 and the vacuum control line 42. A sampling port 6 is installed on the pipeline between the condenser 3 and the collection tank 5. The material collected by the condenser 3 is not refluxed.

[0021] The reactor 1 is made of stainless steel, titanium or nickel. The reactor 1 is provided with a feed inlet 11 and a residue discharge outlet 12. The reactor 1 is provided with a first stirring device 13. The outer wall of the reactor 1 is provided with a first jacket 16. The first jacket 16 is filled with heat transfer oil. The first jacket 16 is provided with a heat transfer oil inlet 14 and a heat transfer oil outlet 15.

[0022] The collection tank 5 is made of stainless steel, quartz, titanium or nickel. The collection tank 5 has a second jacket 55, through which refrigerant flows. The second jacket 55 is provided with a refrigerant inlet 51 and a refrigerant outlet 52. The collection tank 5 is also provided with a condensate inlet 53 and a discharge outlet 56. A second stirring device 54 is provided inside the collection tank 5.

[0023] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

[0024] The apparatus used in the three or more method embodiments is as follows: Method Example 1 This application discloses a method for preparing cyclopentadiene monomers, which employs a dicyclopentadiene pyrolysis reaction.

[0025] 4 kg of dicyclopentadiene was added to the 316L stainless steel reactor 1 through the feed port 11 while it was still hot. The reactor was heated to 160°C using the first jacket 16, and the first stirring device 13 was turned on with a stirring speed of 120~150 rpm.

[0026] The crude cyclopentadiene vaporized in reactor 1 enters a distillation column 2, which is filled with 4*4θ ring packing, has a 50-mesh wire mesh, and 20 theoretical plates for separation. The column is maintained at a top temperature of 40-42°C and a pressure of -5 kPa for collection. By monitoring the pressure gauge, when the pressure exceeds -5 kPa, a vacuum is drawn through vacuum control line 42 to reduce the pressure; when the pressure is below -5 kPa, nitrogen is introduced through nitrogen control line 41 to increase the pressure.

[0027] The 316L stainless steel collection tank 5 has a second jacket containing 55 refrigerant cooled to -10℃. The material is collected through the condensate inlet 53. During the collection process, the second stirring device 54 is activated.

[0028] Gas chromatography analysis of samples taken through sampling port 6 showed that the cyclopentadiene monomer content reached 98.5%. 3.5 kg of material was collected, with a yield of 87.5%.

[0029] Method Example 2 This application discloses a method and apparatus for preparing cyclopentadiene monomer, which employs a dicyclopentadiene pyrolysis reaction.

[0030] 8 kg of dicyclopentadiene is added to the quartz reactor 1 through the feed inlet 11 while it is still hot. The reactor is heated to 180°C using the first jacket 16. The first stirring device 13 is turned on and the stirring speed is 120~150 rpm.

[0031] The crude cyclopentadiene vaporized in reactor 1 enters a distillation column 2, which is filled with 5*5θ ring packing, has a 40-mesh wire mesh, and 30 theoretical plates for separation. The column is maintained at a top temperature of 40-42℃ and a pressure of -1 kPa for collection. By monitoring the pressure gauge, when the pressure exceeds -15 kPa, a vacuum is evacuated via vacuum control line 42 to reduce the pressure; when the pressure falls below -1 kPa, nitrogen is introduced via nitrogen control line 41 to increase the pressure.

[0032] The quartz collection tank 5 has a second jacket 55 where the temperature is lowered to -25°C by a refrigerant. The material is collected through the condensate inlet 53. During the collection process, the second stirring device 54 is activated.

[0033] Gas chromatography analysis of samples taken through sampling port 6 showed that the cyclopentadiene monomer content reached 97.7%. 7.5 kg of material was collected, with a yield of 91.3%.

[0034] Method Example 3 This application discloses a method and apparatus for preparing cyclopentadiene monomer, which employs a dicyclopentadiene pyrolysis reaction.

[0035] 6 kg of dicyclopentadiene was added to the titanium reactor 1 through the feed inlet 11 while it was still hot. The reactor was heated to 170°C using the first jacket 16. The first stirring device 13 was turned on and the stirring speed was 120~150 rpm.

[0036] The crude cyclopentadiene vaporized in reactor 1 is then separated in distillation column 2, which is filled with 10*10θ ring packing, 40-mesh wire mesh, and has 10 theoretical plates. The column is maintained at a top temperature of 40-42°C and a pressure of -5 kPa for collection. Pressure is monitored; when the pressure exceeds -5 kPa, a vacuum is applied via vacuum control line 42 to reduce the pressure; when the pressure falls below -5 kPa, nitrogen is introduced via nitrogen control line 41 to increase the pressure.

[0037] The titanium collection tank 5 has a second jacket containing 55 refrigerant cooled to -15°C. The material is collected through the condensate inlet 53. During the collection process, the second stirring device 54 is activated.

[0038] Gas chromatography analysis of samples taken through sampling port 6 showed that the cyclopentadiene monomer content reached 98.1%. 5.5 kg of material was collected, with a yield of 90.2%.

[0039] Comparative Example 1 The difference between this comparative example and Example 1 is that the theoretical number of plates in the distillation column is 5.

[0040] 4 kg of dicyclopentadiene was added to the 316L stainless steel reactor 1 through the feed port 11 while it was still hot. The reactor was heated to 160°C using the first jacket 16, and the first stirring device 13 was turned on with a stirring speed of 120~150 rpm.

[0041] The crude cyclopentadiene vaporized in reactor 1 enters a distillation column 2, which is filled with 4*4θ ring packing, has a 50-mesh wire mesh, and 5 theoretical plates for separation. The column is collected while maintaining a top temperature of 40-42℃ and a pressure of -5 kPa.

[0042] The 316L stainless steel collection tank 5 has a second jacket containing 55 refrigerant cooled to -10℃. The material is collected through the condensate inlet 53. During the collection process, the second stirring device 54 is activated.

[0043] Gas chromatography analysis of samples taken through sampling port 6 showed that the cyclopentadiene monomer content reached 88.5%. 3.3 kg of material was collected, with a yield of 73.0%.

Claims

1. A method for preparing a cyclopentadiene monomer, characterized in that, Includes the following steps: S1. Dicyclopentadiene is heated to 160~180℃ and cracked and vaporized into crude cyclopentadiene under stirring. S2 and crude cyclopentadiene are fed into a packed distillation column for separation, and the column top temperature is maintained at 40~42℃ and the pressure is -5kPa~-1kPa for collection. S3. Use refrigerant to cool down to -25~-10℃ and collect the material.

2. The method for preparing a cyclopentadiene monomer according to claim 1, characterized in that, In step S1, the heating method is jacketed or electric heating, and the stirring rate is 120~150 rpm.

3. The method for preparing a cyclopentadiene monomer according to claim 1, characterized in that, The packing material mentioned in step S2 is a macroporous packing material.

4. The method for preparing a cyclopentadiene monomer according to claim 3, characterized in that, The metal wire mesh aperture of the macroporous packing material mentioned in step S2 is not less than 50 mesh.

5. The method for preparing a cyclopentadiene monomer according to claim 1, characterized in that, The packing material mentioned in step S2 is θ-ring packing.

6. The method for preparing a cyclopentadiene monomer according to claim 5, characterized in that, The diameter of the θ-ring packing ring mentioned in step S2 is not less than 4×4 mm.

7. The method for preparing a cyclopentadiene monomer according to claim 1, characterized in that, In step S2, the theoretical number of plates in the distillation column is 10 to 30.

8. An apparatus for preparing a cyclopentadiene monomer, used in the method for preparing a cyclopentadiene monomer according to any one of claims 1-7, characterized in that, The system includes a reaction vessel (1), a distillation column (2), and a collection tank (5) connected in sequence by pipelines. A condenser (3) is provided between the distillation column (2) and the collection tank (5). Both the condenser (3) and the collection tank (5) are connected to a nitrogen control line (41) and a vacuum control line (42). Pressure gauges are provided on the nitrogen control line (41) and the vacuum control line (42). A sampling port (6) is provided on the pipeline between the condenser (3) and the collection tank (5).

9. The apparatus for preparing cyclopentadiene monomer according to claim 8, characterized in that, The reactor (1) is made of stainless steel, titanium or nickel. The reactor (1) is provided with a feed inlet (11) and a reactor residue discharge outlet (12). The reactor (1) is provided with a first stirring device (13). The reactor (1) is provided with a first jacket (16) on its outer wall. The first jacket (16) is filled with heat transfer oil. The first jacket (16) is provided with a heat transfer oil inlet (14) and a heat transfer oil outlet (15).

10. The apparatus for preparing cyclopentadiene monomer according to claim 8, characterized in that, The collection tank (5) is made of stainless steel, quartz, titanium or nickel. The collection tank (5) is equipped with a second jacket (55), which is filled with refrigerant. The second jacket (55) is provided with a refrigerant inlet (51) and a refrigerant outlet (52). The collection tank (5) is also provided with a condensate inlet (53) and a discharge outlet (56). The collection tank (5) is provided with a second stirring device (54).

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