Device and process for co-production of 2,4-di-tert-butylphenol with 4-tert-butylphenol

Abstract

The invention belongs to the field of phenol production technology, and in particular to a kind of device and process for co-producing 2,4-di-tert-butylphenols of p-tert-butylphenol.The device of the described p-tert-butylphenol co-production 2,4-di-tert-butylphenol, including reactor, reactor is connected with one-level rectifying tower by receiving kettle, one-level rectifying tower is connected with three-stage rectifying tower by secondary rectifying tower, reactor is provided with reactor vacuum pump pipeline, reactor vacuum pump pipeline is connected with reactor vacuum pump, reactor vacuum pump is connected with metal film recovery box by entering metal film recovery box pipeline, metal film recovery box is connected with reactor by recovery tank, one-level rectifying tower is connected with phenol isobutylene receiving kettle pipeline by entering phenol isobutylene receiving kettle.This program is reclaimed by the setting of metal film recovery box by gas phase isobutylene and phenol, avoids the waste of energy, improves production efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of phenol production, and particularly relates to a device and process for co-producing 2,4-di-tert-butylphenol with p-tert-butylphenol. Background Art

[0002] 4-tert-Butylphenol and 2,4-di-tert-butylphenol are important fine chemical raw materials, widely used in synthetic resins, pesticides, pharmaceuticals, and other fields. The production process for 4-tert-Butylphenol primarily uses phenol and isobutylene as raw materials, and is prepared through steps such as alkylation, isomerization, and distillation.

[0003] During production, the reaction of tert-butylphenol produces approximately 7% of 2,4-di-tert-butylphenol as an impurity. The original process involved simple crude distillation to recover this impurity, which not only wasted energy but also damaged the catalyst, shortening its lifespan and increasing production costs. Furthermore, the exhaust gas, which contained large amounts of isobutylene and phenol, was typically directly incinerated in the fuel gas pipeline, resulting in significant waste. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the present invention aims to provide a device for co-producing 2,4-di-tert-butylphenol from p-tert-butylphenol, which can co-produce p-tert-butylphenol and 2,4-di-tert-butylphenol, greatly improving product returns and reducing damage to the catalyst. By setting up a metal membrane recovery box, isobutylene and phenol in the gas phase are recovered, thus avoiding energy waste and greatly improving production efficiency.

[0005] Another object of the present invention is to provide a method for co-producing 2,4-di-tert-butylphenol with 4-tert-butylphenol, which greatly improves production efficiency and raw material utilization by setting production process parameters.

[0006] The technical solution adopted by the present invention is:

[0007] The device for co-producing 2,4-di-tert-butylphenol with p-tert-butylphenol comprises a reactor, which is connected to a first-stage distillation tower via a receiving reactor, and the first-stage distillation tower is connected to a tertiary distillation tower via a second-stage distillation tower. The reactor is provided with a reactor vacuum pump inlet pipeline, which is connected to the reactor vacuum pump, and the reactor vacuum pump is connected to a metal film recovery box via a metal film recovery box inlet pipeline, which is connected to the reactor via a recovery tank. The first-stage distillation tower is connected to a phenol-isobutylene receiving reactor via a phenol-isobutylene receiving reactor inlet pipeline, the second-stage distillation tower is connected to a p-tert-butylphenol receiving reactor via a p-tert-butylphenol receiving reactor inlet pipeline, and the tertiary distillation tower is connected to a 2,4-di-tert-butylphenol receiving reactor via a 2,4-di-tert-butylphenol receiving reactor inlet pipeline. A tertiary distillation tower discharge pipeline is provided below the tertiary distillation tower.

[0008] The reactor is provided with an isobutylene inlet pipe and a phenol inlet pipe, and a return pipe is provided between the recovery tank and the reactor.

[0009] A first-stage distillation tower feed pump is provided between the receiving kettle and the first-stage distillation tower, and a first-stage distillation tower feed pump discharge pipe is provided between the first-stage distillation tower feed pump and the first-stage distillation tower. The connection point between the first-stage distillation tower feed pump discharge pipe and the first-stage distillation tower is lower than the connection point between the phenol isobutylene receiving kettle pipeline and the first-stage distillation tower.

[0010] A secondary distillation tower feed pump is provided between the primary distillation tower and the secondary distillation tower, a secondary distillation tower feed pump discharge pipe is connected between the secondary distillation tower feed pump and the secondary distillation tower, and the connection point between the secondary distillation tower feed pump discharge pipe and the secondary distillation tower is lower than the connection point between the p-tert-butylphenol receiving kettle inlet pipe and the secondary distillation tower.

[0011] A third-stage distillation tower feed pump is provided between the secondary distillation tower and the third-stage distillation tower, a third-stage distillation tower feed pump discharge pipe is provided between the third-stage distillation tower feed pump and the third-stage distillation tower, and the connection point between the third-stage distillation tower feed pump discharge pipe and the third-stage distillation tower is lower than the connection point between the 2,4-di-tert-butylphenol receiving kettle pipeline and the third-stage distillation tower.

[0012] A first-stage vacuum pump pipeline is provided above the first-stage distillation tower, a first-stage vacuum pump is connected to the first-stage vacuum pump pipeline, and the first-stage vacuum pump is connected to the metal film recovery box pipeline through a pipeline.

[0013] The secondary distillation tower is provided with a secondary vacuum pump inlet pipeline, which is connected to the secondary vacuum pump, and the secondary vacuum pump is connected to the metal film recovery box inlet pipeline through a pipeline.

[0014] The three-stage distillation tower is provided with a three-stage vacuum pump inlet pipeline, which is connected to the three-stage vacuum pump, and the three-stage vacuum pump is connected to the metal film recovery box inlet pipeline through a pipeline.

[0015] The metal film recovery box is provided with a cooling device inside, and the cooling device is connected to the long-distance demixer through an accelerated temperature control separation box. A demixing plate is provided inside the long-distance demixer, an upper air chamber is provided above the demixing plate, and a lower air chamber is provided below the demixing plate. A separation membrane is provided inside the upper air chamber, and both sides of the separation membrane are respectively connected to a vacuum pump and an exhaust gas outlet pipe. The vacuum pump is located on the side away from the accelerated temperature control separation box, a separator is provided on the lower air chamber, and a separation pipe is provided on the separator. A first-level centrifugal acceleration pipe, a second-level centrifugal acceleration pipe, and a third-level centrifugal acceleration pipe are provided inside the accelerated temperature control separation box in sequence. The first-level centrifugal acceleration pipe is connected to the cooling device, a first-level accelerator is provided between the first-level centrifugal acceleration pipe and the second-level centrifugal acceleration pipe, and a second-level accelerator is provided between the second-level centrifugal acceleration pipe and the third-level centrifugal acceleration pipe. The vacuum pump is connected to the recovery tank, and the bottom of the separator is connected to the recovery tank through a pipe.

[0016] The separation membrane is a metal-organic framework (MOFs) membrane. Phenol has a boiling point of 181.7°C and a melting point of 43°C; isobutylene has a boiling point of -6.9°C and a melting point of -140°C; 2,4-di-tert-butylphenol has a melting point between 95-98°C, and p-tert-butylphenol has a melting point between 101-103°C.

[0017] The process for co-producing 2,4-di-tert-butylphenol from p-tert-butylphenol comprises the following steps:

[0018] a. adding isobutylene and phenol to a reactor and reacting at a temperature of 80-90 ° C. After the reaction is completed, the mixture is passed through a receiving kettle and enters a primary distillation tower. The top temperature of the primary distillation tower is 140-150 ° C., the vacuum degree of the top of the tower is -0.096 MPa, the bottom temperature is 190-200 ° C., the vacuum degree of the bottom of the tower is -0.092 MPa, and internal reflux is used. The reflux ratio is 3:4. The front fraction is extracted from the phenol-isobutylene receiving kettle, and the gas phase enters the metal membrane recovery box through a primary vacuum pump;

[0019] b. The liquid phase extracted from the bottom of the primary distillation tower enters the secondary distillation tower through the secondary distillation tower feed pump. The top temperature of the secondary distillation tower is 140-150°C, the top vacuum is -0.096MPa, the bottom temperature is 190-200°C, the bottom vacuum is -0.092MPa, and internal reflux is adopted with a reflux ratio of 1:4. 4-tert-butylphenol is extracted from the 4-tert-butylphenol receiving kettle, and the gas phase enters the metal membrane recovery box through the secondary vacuum pump;

[0020] c. The liquid phase extracted from the bottom of the secondary distillation tower enters the tertiary distillation tower through the tertiary distillation tower feed pump. The top temperature of the tertiary distillation tower is 150-170°C, the top vacuum degree is -0.099MPa, the bottom temperature is 190-200°C, the bottom vacuum degree is -0.094MPa, and internal reflux is adopted with a reflux ratio of 4:3. 2,4-di-tert-butylphenol is extracted from the 2,4-di-tert-butylphenol receiving kettle, and the gas phase enters the metal membrane recovery box through the tertiary vacuum pump;

[0021] d. After the gas phase enters the metal membrane recovery box, it first enters the cooling device to cool to 60-70°C, and then enters the accelerated temperature-controlled separation box for centrifugal accelerated stratification. After that, the gas phase enters the long-distance stratifier and is physically stratified by the stratification plate. Most of the unliquefied isobutylene enters the upper gas chamber, passes through the separation membrane, and enters the recovery tank through the vacuum pump. The mixed phase in the lower gas chamber is separated by the separator, and the liquid phase enters the recovery tank.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) By setting up a metal film recovery box, isobutylene and phenol are recovered after cooling, which avoids energy waste, greatly improves production efficiency, reduces production costs, and eliminates the need for post-processing of the product;

[0024] (2) Separating 2,4-di-tert-butylphenol and treating it as a product greatly increases profits and reduces production costs.

[0025] (3) By setting the production process parameters, the production efficiency was greatly improved and the separation purity of tert-butylphenol and 2,4-di-tert-butylphenol was improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic structural diagram of a device for co-producing 2,4-di-tert-butylphenol from p-tert-butylphenol according to the present invention;

[0027] Figure 2 This is a schematic structural diagram of a metal film recovery box device of the present invention;

[0028] In the figure: 1. Reactor; 2. Receiving kettle; 3. Primary distillation tower; 4. Secondary distillation tower; 5. Tertiary distillation tower; 6. Primary vacuum pump; 7. Secondary vacuum pump; 8. Tertiary vacuum pump; 9. Metal film recovery box; 10. Return pipe; 11. Feed pump for primary distillation tower; 12. Feed pump for secondary distillation tower; 13. Feed pump for tertiary distillation tower; 14. Pipeline to phenol-isobutylene receiving kettle; 15. Phenol-isobutylene receiving kettle; 16. Pipeline to p-tert-butylphenol receiving kettle; 17. p-tert-butylphenol receiving kettle; 18. Pipeline to 2,4-di-tert-butylphenol receiving kettle; 19. 2,4-di-tert-butylphenol receiving kettle; 20. Pipeline to primary vacuum pump; 21. Pipeline to secondary vacuum pump; 22. Pipeline to tertiary vacuum pump; 23. Pipeline to metal film recovery box ; 24. Isobutylene inlet pipeline; 25. Phenol inlet pipeline; 26. Reactor vacuum pump inlet pipeline; 27. First-stage distillation tower feed pump discharge pipeline; 28. Second-stage distillation tower feed pump discharge pipeline; 29. Third-stage distillation tower feed pump discharge pipeline; 30. Third-stage distillation tower discharge pipeline; 31. Reactor vacuum pump; 32. Recovery tank; 33. Cooling device; 34. Accelerated temperature control separation box; 35. Long-distance stratifier; 36. First-stage centrifugal acceleration pipeline; 37. First-stage accelerator; 38. Second-stage centrifugal acceleration pipeline; 39. Second-stage accelerator; 40. Third-stage centrifugal acceleration pipeline; 41. Stratification plate; 42. Separation membrane; 43. Vacuum pump; 44. Separator; 45. Separation pipeline; 46. Waste gas outlet pipeline; 47. Upper air chamber; 48. Lower air chamber. DETAILED DESCRIPTION

[0029] The present invention is further described below with reference to the following examples, but they do not limit the implementation of the present invention.

[0030] Example 1

[0031] like Figure 1As shown, the device for co-producing 2,4-di-tert-butylphenol with tert-butylphenol includes a reactor 1, which is connected to a primary distillation tower 3 through a receiving reactor 2, and the primary distillation tower 3 is connected to a tertiary distillation tower 5 through a secondary distillation tower 4. The reactor 1 is provided with a reactor vacuum pump inlet pipe 26, which is connected to a reactor vacuum pump 31, and the reactor vacuum pump 31 is connected to a metal film recovery box 9 through a metal film recovery box inlet pipe 23. The metal film recovery box 9 is connected to reactor 1 via recovery tank 32. The primary distillation tower 3 is connected to a phenol-isobutylene receiving kettle 15 via a phenol-isobutylene receiving kettle inlet pipe 14. The secondary distillation tower 4 is connected to a p-tert-butylphenol receiving kettle 17 via a p-tert-butylphenol receiving kettle inlet pipe 16. The tertiary distillation tower 5 is connected to a 2,4-di-tert-butylphenol receiving kettle 19 via a 2,4-di-tert-butylphenol receiving kettle inlet pipe 18. A tertiary distillation tower discharge pipe 30 is provided below the tertiary distillation tower 5. Reactor 1 is provided with an isobutylene inlet pipe 24 and a phenol inlet pipe 25. A return pipe 10 is provided between the recovery tank 32 and reactor 1. A primary distillation tower feed pump 11 is provided between the receiving kettle 2 and the primary distillation tower 3. A primary distillation tower feed pump discharge pipe 27 is provided between the primary distillation tower feed pump 11 and the primary distillation tower 3. The connection point between the primary distillation tower feed pump discharge pipe 27 and the primary distillation tower 3 is lower than the connection point between the phenol-isobutylene receiving kettle inlet pipe 14 and the primary distillation tower 3. A secondary distillation tower feed pump 12 is provided between the primary distillation tower 3 and the secondary distillation tower 4. A secondary distillation tower feed pump discharge pipe 28 is connected between the secondary distillation tower feed pump 12 and the secondary distillation tower 4. The connection point between the secondary distillation tower feed pump discharge pipe 28 and the secondary distillation tower 4 is lower than the connection point between the p-tert-butylphenol receiving kettle inlet pipe 16 and the secondary distillation tower 4. A tertiary distillation tower feed pump 13 is provided between the secondary distillation tower 4 and the tertiary distillation tower 5. A tertiary distillation tower feed pump discharge pipe 29 is provided between the tertiary distillation tower feed pump 13 and the tertiary distillation tower 5. The connection point between the tertiary distillation tower feed pump discharge pipe 29 and the tertiary distillation tower 5 is lower than the connection point between the 2,4-di-tert-butylphenol receiving kettle inlet pipe 18 and the tertiary distillation tower 5. A first-stage vacuum pump inlet pipe 20 is provided above the first-stage distillation tower 3. A first-stage vacuum pump inlet pipe 20 is connected to a first-stage vacuum pump 6. The first-stage vacuum pump 6 is connected to a metal film recovery tank inlet pipe 23 via a pipe. A second-stage vacuum pump inlet pipe 21 is provided on the second-stage distillation tower 4. The second-stage vacuum pump inlet pipe 21 is connected to a second-stage vacuum pump 7. The second-stage vacuum pump 7 is connected to a metal film recovery tank inlet pipe 23 via a pipe. The three-stage distillation tower 5 is provided with a three-stage vacuum pump pipeline 22, which is connected to the three-stage vacuum pump 8. The three-stage vacuum pump 8 is connected to the metal film recovery box pipeline 23 through a pipeline. Figure 2As shown, a cooling device 33 is provided inside the metal film recovery box 9, and the cooling device 33 is connected to the long-distance delaminator 35 through an accelerated temperature control separation box 34. A delaminator 35 is provided with a delamination plate 41 inside the long-distance delaminator 35, and an upper air chamber 47 is provided above the delamination plate 41, and a lower air chamber 48 is provided below the delamination plate 41. A separation membrane 42 is provided inside the upper air chamber 47, and a vacuum pump 43 and an exhaust gas outlet pipe 46 are connected to both sides of the separation membrane 42. The vacuum pump 43 is located on the side away from the accelerated temperature control separation box 34, and a separator 44 is provided on the lower air chamber 48. Separator 44 is provided with a separation pipe 45. Acceleration temperature-controlled separation box 34 is sequentially provided with a first-stage centrifugal acceleration pipe 36, a second-stage centrifugal acceleration pipe 38, and a third-stage centrifugal acceleration pipe 40. First-stage centrifugal acceleration pipe 36 is connected to cooling device 33. A first-stage accelerator 37 is provided between first-stage centrifugal acceleration pipe 36 and second-stage centrifugal acceleration pipe 38. A second-stage accelerator 39 is provided between second-stage centrifugal acceleration pipe 38 and third-stage centrifugal acceleration pipe 40. A vacuum pump 43 is connected to recovery tank 32, and the separator 44 is connected to recovery tank 32 via a pipe below. The pipe after vacuum pump 43 is used to recover isobutylene, and separation pipe 45 is used to recover phenol. Separation pipe 45 is used for high-level recovery. Separator 44 is primarily used for liquid-solid separation.

[0032] Example 2

[0033] This embodiment is prepared by the device for co-producing 2,4-di-tert-butylphenol from tert-butylphenol described in Example 1.

[0034] The method for co-producing 2,4-di-tert-butylphenol with p-tert-butylphenol comprises the following steps:

[0035] a. Isobutylene and phenol were added to the reactor 1 and reacted at a temperature of 85 ° C. After the reaction, the mixture was received by the reactor 2 and then entered into a primary distillation tower 3. The top temperature of the primary distillation tower 3 was 145 ° C., the vacuum degree of the top of the tower was -0.096 MPa, the bottom temperature was 195 ° C., the vacuum degree of the bottom of the tower was -0.092 MPa, and the internal reflux was used. The reflux ratio was 3:4. The front fraction of phenol and isobutylene was extracted from the receiving reactor 15, and the gas phase was passed through a primary vacuum pump 6 and entered into the metal film recovery box 9;

[0036] b. The liquid phase extracted from the bottom of the primary distillation tower 3 enters the secondary distillation tower feed pump 12 into the secondary distillation tower 4, the secondary distillation tower 4 top temperature 145 ° C, the top vacuum -0.096MPa, the bottom temperature 195 ° C, the bottom vacuum -0.092MPa, using internal reflux, reflux ratio 1: 4, p-tert-butylphenol receiving kettle 17 extracted p-tert-butylphenol, the gas phase enters the metal film recovery box 9 via the secondary vacuum pump 7;

[0037] c. The liquid phase extracted from the bottom of the secondary distillation tower 4 enters the tertiary distillation tower 5 through the tertiary distillation tower feed pump 13. The top temperature of the tertiary distillation tower 5 is 160°C, the top vacuum is -0.099MPa, the bottom temperature is 195°C, the bottom vacuum is -0.094MPa, and internal reflux is adopted. The reflux ratio is 4:3, 2,4-di-tert-butylphenol is extracted from the 2,4-di-tert-butylphenol receiving kettle 19, and the gas phase enters the metal membrane recovery box 9 through the tertiary vacuum pump 8;

[0038] d. After the gas phase enters the metal membrane recovery box 9, it first enters the cooling device 33 to be cooled to 65°C, and then enters the accelerated temperature control separation box 34 for centrifugal accelerated stratification. After that, the gas phase enters the long-distance stratifier 35 and is physically stratified by the stratification plate 41. Most of the unliquefied isobutylene enters the upper gas chamber 47, passes through the separation membrane 42, and enters the recovery tank 32 through the vacuum pump 43. After the mixed phase in the lower gas chamber 48 is separated by the separator 44, the gas phase enters the recovery tank 32.

[0039] The purity of the obtained p-tert-butylphenol product is 99.98 wt %; the purity of the obtained 2,4-di-tert-butylphenol product is 99.8 wt %; the isobutylene recovered in the recovery tank is 2.8 % of the amount of isobutylene added, and the liquid-phase phenol recovered in the separator is 2.1 % of the amount of phenol added.

[0040] Example 3

[0041] This embodiment is prepared by the device for co-producing 2,4-di-tert-butylphenol from tert-butylphenol described in Example 1.

[0042] The method for co-producing 2,4-di-tert-butylphenol with p-tert-butylphenol comprises the following steps:

[0043] a. Isobutylene and phenol were added to the reactor 1 and reacted at a temperature of 90 ° C. After the reaction, the reactor 2 was received and then entered into a primary distillation tower 3. The top temperature of the primary distillation tower 3 was 150 ° C., the vacuum degree of the top of the tower was -0.096 MPa, the bottom temperature was 200 ° C., the vacuum degree of the bottom of the tower was -0.092 MPa, and the internal reflux was used. The reflux ratio was 3:4. The front fraction of phenol and isobutylene was extracted from the receiving reactor 15, and the gas phase was passed through a primary vacuum pump 6 and entered into the metal film recovery box 9;

[0044] b. The liquid phase extracted from the bottom of the primary distillation tower 3 enters the secondary distillation tower feed pump 12 into the secondary distillation tower 4, the secondary distillation tower 4 top temperature 140 ° C, the top vacuum -0.096MPa, the bottom temperature 190 ° C, the bottom vacuum -0.092MPa, using internal reflux, reflux ratio 1: 4, p-tert-butylphenol receiving kettle 17 extracted p-tert-butylphenol, the gas phase enters the metal film recovery box 9 via the secondary vacuum pump 7;

[0045] c. The liquid phase extracted from the bottom of the secondary distillation tower 4 enters the tertiary distillation tower 5 through the tertiary distillation tower feed pump 13. The top temperature of the tertiary distillation tower 5 is 170°C, the top vacuum is -0.099MPa, the bottom temperature is 200°C, the bottom vacuum is -0.094MPa, and internal reflux is adopted. The reflux ratio is 4:3, 2,4-di-tert-butylphenol is extracted from the 2,4-di-tert-butylphenol receiving kettle 19, and the gas phase enters the metal membrane recovery box 9 through the tertiary vacuum pump 8;

[0046] d. After the gas phase enters the metal membrane recovery box 9, it first enters the cooling device 33 to be cooled to 60°C, and then enters the accelerated temperature control separation box 34 for centrifugal accelerated stratification. After that, the gas phase enters the long-distance stratifier 35 and is physically stratified by the stratification plate 41. Most of the unliquefied isobutylene enters the upper gas chamber 47, passes through the separation membrane 42, and enters the recovery tank 32 through the vacuum pump 43. After the mixed phase in the lower gas chamber 48 is separated by the separator 44, the gas phase enters the recovery tank 32.

[0047] The purity of the obtained p-tert-butylphenol product is 99.97 wt %; the purity of the obtained 2,4-di-tert-butylphenol product is 99.8 wt %; the isobutylene recovered in the recovery tank is 2.7 % of the amount of isobutylene added, and the liquid-phase phenol recovered in the separator is 1.9 % of the amount of phenol added.

[0048] Example 4

[0049] This embodiment is prepared by the device for co-producing 2,4-di-tert-butylphenol from tert-butylphenol described in Example 1.

[0050] The method for co-producing 2,4-di-tert-butylphenol with p-tert-butylphenol comprises the following steps:

[0051] a. Isobutylene and phenol were added to the reactor 1 and reacted at a temperature of 80-90 ° C. After the reaction, the mixture was received by the reactor 2 and then entered into a primary distillation tower 3. The top temperature of the primary distillation tower 3 was 140 ° C., the vacuum degree of the top of the tower was -0.096 MPa, the bottom temperature was 190 ° C., the vacuum degree of the bottom of the tower was -0.092 MPa, and the internal reflux was used. The reflux ratio was 3:4. The front fraction of the phenol-isobutylene receiving reactor 15 was extracted, and the gas phase was passed through a primary vacuum pump 6 and entered into the metal film recovery box 9;

[0052] b. The liquid phase extracted from the bottom of the primary distillation tower 3 enters the secondary distillation tower feed pump 12 into the secondary distillation tower 4, the secondary distillation tower 4 top temperature 150 ° C, the top vacuum -0.096MPa, the bottom temperature 200 ° C, the bottom vacuum -0.092MPa, using internal reflux, reflux ratio 1: 4, p-tert-butylphenol receiving kettle 17 extracted p-tert-butylphenol, the gas phase enters the metal film recovery box 9 via the secondary vacuum pump 7;

[0053] c. The liquid phase extracted from the bottom of the secondary distillation tower 4 enters the tertiary distillation tower 5 through the tertiary distillation tower feed pump 13. The top temperature of the tertiary distillation tower 5 is 150°C, the top vacuum is -0.099MPa, the bottom temperature is 190°C, the bottom vacuum is -0.094MPa, and internal reflux is adopted. The reflux ratio is 4:3, 2,4-di-tert-butylphenol is extracted from the 2,4-di-tert-butylphenol receiving kettle 19, and the gas phase enters the metal membrane recovery box 9 through the tertiary vacuum pump 8;

[0054] d. After the gas phase enters the metal membrane recovery box 9, it first enters the cooling device 33 to be cooled to 70°C, and then enters the accelerated temperature control separation box 34 for centrifugal accelerated stratification. After that, the gas phase enters the long-distance stratifier 35 and is physically stratified by the stratification plate 41. Most of the unliquefied isobutylene enters the upper gas chamber 47, passes through the separation membrane 42, and enters the recovery tank 32 through the vacuum pump 43. After the mixed phase in the lower gas chamber 48 is separated by the separator 44, the gas phase enters the recovery tank 32.

[0055] The purity of the obtained p-tert-butylphenol product is 99.98 wt %; the purity of the obtained 2,4-di-tert-butylphenol product is 99.7 wt %; the isobutylene recovered in the recovery tank is 2.5 % of the amount of isobutylene added, and the liquid-phase phenol recovered in the separator is 1.8 % of the amount of phenol added.

[0056] Comparative Example 1

[0057] The method for co-producing 2,4-di-tert-butylphenol with p-tert-butylphenol comprises the following steps:

[0058] a. Isobutylene and phenol were added to the reactor 1 and reacted at a temperature of 80 ° C. After the reaction, the mixture was received by the reactor 2 and then entered into a primary distillation tower 3. The top temperature of the primary distillation tower 3 was 140 ° C., the vacuum degree of the top of the tower was -0.096 MPa, the bottom temperature was 190 ° C., the vacuum degree of the bottom of the tower was -0.092 MPa, and the internal reflux was used. The reflux ratio was 3:4. The front fraction of phenol and isobutylene was extracted from the receiving reactor 15, and the gas phase was passed through a primary vacuum pump 6 and entered into the metal film recovery box 9;

[0059] b. The liquid phase extracted from the bottom of the primary distillation tower 3 enters the secondary distillation tower 4 through the secondary distillation tower feed pump 12, the secondary distillation tower 4 top temperature 145 ° C, the top vacuum -0.096MPa, the bottom temperature 190 ° C, the bottom vacuum -0.092MPa, using internal reflux, reflux ratio 1: 4, p-tert-butylphenol receiving kettle 17 extracted p-tert-butylphenol, the gas phase enters the metal film recovery box 9 through the secondary vacuum pump 7;

[0060] c. The liquid phase extracted from the bottom of the secondary distillation tower 4 enters the tertiary distillation tower 5 through the tertiary distillation tower feed pump 13. The top temperature of the tertiary distillation tower 5 is 170°C, the top vacuum is -0.099 MPa, the bottom temperature is 200°C, the bottom vacuum is -0.094 MPa, and internal reflux is adopted with a reflux ratio of 4:3. 2,4-di-tert-butylphenol is extracted from the 2,4-di-tert-butylphenol receiving kettle 19.

[0061] The purity of the obtained p-tert-butylphenol product is 99.5wt%; the purity of the obtained 2,4-di-tert-butylphenol product is 98.6wt%.

[0062] The test results of Examples 2-4 and Comparative Example 1 are shown in Table 1.

[0063] Table 1 Test results of Examples 2-4 and Comparative Example 1

[0064]

[0065] As shown in Table 1 and the test data of the comparative examples of the various embodiments, the present invention not only significantly increases the recovery of 2,4-di-tert-butylphenol, but also improves the purity of the resulting product to a certain extent. In particular, the recovery of isobutylene and phenol significantly reduces production costs. Based on an annual consumption of 30,000 tons of isobutylene and 20,000 tons of phenol, the current cost of isobutylene is 12,000 yuan per ton and that of phenol is 8,000 yuan per ton. This saves approximately 10 million yuan in raw material costs annually for isobutylene and approximately 3 million yuan for phenol.

Claims

1. A device for co-producing 2,4-di-tert-butylphenol with tert-butylphenol, characterized in that: The invention comprises a reactor (1), wherein the reactor (1) is connected to a first-stage distillation tower (3) through a receiving reactor (2), and the first-stage distillation tower (3) is connected to a third-stage distillation tower (5) through a second-stage distillation tower (4). The reactor (1) is provided with a reactor vacuum pump inlet pipe (26), the reactor vacuum pump inlet pipe (26) is connected to a reactor vacuum pump (31), the reactor vacuum pump (31) is connected to a metal film recovery box (9) through a metal film recovery box inlet pipe (23), and the metal film recovery box (9) is connected to a recovery tank (32). The first-stage distillation tower (3) is connected to the phenol-isobutylene receiving kettle (15) through the phenol-isobutylene receiving kettle inlet pipe (14), the second-stage distillation tower (4) is connected to the p-tert-butylphenol receiving kettle (17) through the p-tert-butylphenol receiving kettle inlet pipe (16), and the third-stage distillation tower (5) is connected to the 2,4-di-tert-butylphenol receiving kettle (19) through the 2,4-di-tert-butylphenol receiving kettle inlet pipe (18). A third-stage distillation tower discharge pipe (30) is provided below the third-stage distillation tower (5); A first-stage vacuum pump pipeline (20) is provided above the first-stage distillation tower (3), and a first-stage vacuum pump (6) is connected to the first-stage vacuum pump pipeline (20), and the first-stage vacuum pump (6) is connected to the metal film recovery box pipeline (23) through a pipeline; The secondary distillation tower (4) is provided with a secondary vacuum pump inlet pipe (21), the secondary vacuum pump inlet pipe (21) is connected to the secondary vacuum pump (7), and the secondary vacuum pump (7) is connected to the metal film recovery box inlet pipe (23) through a pipe; The three-stage distillation tower (5) is provided with a three-stage vacuum pump inlet pipeline (22), the three-stage vacuum pump inlet pipeline (22) is connected to the three-stage vacuum pump (8), and the three-stage vacuum pump (8) is connected to the metal film recovery box inlet pipeline (23) through a pipeline; The metal film recovery box (9) is provided with a cooling device (33) inside, and the cooling device (33) is connected to the long-distance stratifier (35) through the accelerated temperature control separation box (34). The long-distance stratifier (35) is provided with a stratification plate (41) inside, and an upper air chamber (47) is provided above the stratification plate (41), and a lower air chamber (48) is provided below the stratification plate (41). A separation membrane (42) is provided inside the upper air chamber (47), and a vacuum pump (43) and an exhaust gas outlet pipe (46) are connected to both sides of the separation membrane (42). The vacuum pump (43) is located on the side away from the accelerated temperature control separation box (34), and a separator (44) is provided on the lower air chamber (48). A separation pipe (45) is provided on the separator (44), and a first-stage centrifugal acceleration pipe (36), a second-stage centrifugal acceleration pipe (38), and a third-stage centrifugal acceleration pipe (40) are sequentially provided inside the accelerated temperature-controlled separation box (34). The first-stage centrifugal acceleration pipe (36) is connected to the cooling device (33), a first-stage accelerator (37) is provided between the first-stage centrifugal acceleration pipe (36) and the second-stage centrifugal acceleration pipe (38), and a second-stage accelerator (39) is provided between the second-stage centrifugal acceleration pipe (38) and the third-stage centrifugal acceleration pipe (40). The vacuum pump (43) is connected to the recovery tank (32), and the lower part of the separator (44) is connected to the recovery tank (32) through a pipe. The separation membrane is a metal-organic framework membrane.

2. The device for co-producing 2,4-di-tert-butylphenol with p-tert-butylphenol according to claim 1, characterized in that: The reactor (1) is provided with an isobutylene inlet pipe (24) and a phenol inlet pipe (25), and a return pipe (10) is provided between the recovery tank (32) and the reactor (1).

3. The device for co-producing 2,4-di-tert-butylphenol with p-tert-butylphenol according to claim 1, characterized in that: A first-stage distillation tower feed pump (11) is provided between the receiving kettle (2) and the first-stage distillation tower (3), and a first-stage distillation tower feed pump discharge pipe (27) is provided between the first-stage distillation tower feed pump (11) and the first-stage distillation tower (3). The connection point between the first-stage distillation tower feed pump discharge pipe (27) and the first-stage distillation tower (3) is lower than the connection point between the phenol isobutylene receiving kettle pipe (14) and the first-stage distillation tower (3).

4. The device for co-producing 2,4-di-tert-butylphenol with p-tert-butylphenol according to claim 1, characterized in that: A secondary distillation tower feed pump (12) is provided between the primary distillation tower (3) and the secondary distillation tower (4), a secondary distillation tower feed pump discharge pipe (28) is connected between the secondary distillation tower feed pump (12) and the secondary distillation tower (4), and the connection point between the secondary distillation tower feed pump discharge pipe (28) and the secondary distillation tower (4) is lower than the connection point between the p-tert-butylphenol receiving kettle inlet pipe (16) and the secondary distillation tower (4).

5. The device for co-producing 2,4-di-tert-butylphenol with p-tert-butylphenol according to claim 1, characterized in that: A third-stage distillation tower feed pump (13) is provided between the second-stage distillation tower (4) and the third-stage distillation tower (5), and a third-stage distillation tower feed pump discharge pipe (29) is provided between the third-stage distillation tower feed pump (13) and the third-stage distillation tower (5). The connection point between the third-stage distillation tower feed pump discharge pipe (29) and the third-stage distillation tower (5) is lower than the connection point between the 2,4-di-tert-butylphenol receiving kettle inlet pipe (18) and the third-stage distillation tower (5).

6. A process for co-producing 2,4-di-tert-butylphenol with p-tert-butylphenol, characterized in that: The device for co-producing 2,4-di-tert-butylphenol with p-tert-butylphenol according to any one of claims 1 to 5 comprises the following steps: a. Add isobutylene and phenol to a reactor (1) and react at a temperature of 80-90°C. After the reaction is completed, the isobutylene and phenol are passed through a receiving reactor (2) and then enter a primary distillation tower (3). The primary distillation tower (3) has a top temperature of 140-150°C, a top vacuum of -0.096 MPa, a bottom temperature of 190-200°C, and a bottom vacuum of -0.092 MPa. Internal reflux is used with a reflux ratio of 3:

4. The front fraction is extracted from the phenol-isobutylene receiving reactor (15), and the gas phase enters a metal membrane recovery box (9) through a primary vacuum pump (6); b. The liquid phase extracted from the bottom of the primary distillation tower (3) enters the secondary distillation tower (4) through the secondary distillation tower feed pump (12). The top temperature of the secondary distillation tower (4) is 140-150°C, the top vacuum degree is -0.096MPa, the bottom temperature is 190-200°C, the bottom vacuum degree is -0.092MPa, and internal reflux is adopted with a reflux ratio of 1:

4. The p-tert-butylphenol is extracted from the p-tert-butylphenol receiving kettle (17), and the gas phase enters the metal membrane recovery box (9) through the secondary vacuum pump (7); c. The liquid phase extracted from the bottom of the secondary distillation tower (4) enters the tertiary distillation tower (5) through the tertiary distillation tower feed pump (13). The top temperature of the tertiary distillation tower (5) is 150-170°C, the top vacuum degree is -0.099MPa, the bottom temperature is 190-200°C, the bottom vacuum degree is -0.094MPa, and internal reflux is adopted with a reflux ratio of 4:

3. 2,4-di-tert-butylphenol is extracted from the 2,4-di-tert-butylphenol receiving kettle (19), and the gas phase enters the metal membrane recovery box (9) through the tertiary vacuum pump (8); d. After the gas phase enters the metal membrane recovery box (9), it first enters the cooling device (33) to cool to 60-70°C, and then enters the accelerated temperature control separation box (34) for centrifugal accelerated stratification. After that, the gas phase enters the long-distance stratifier (35) and is physically stratified by the stratification plate (41). Most of the unliquefied isobutylene enters the upper gas chamber (47), passes through the separation membrane (42), and enters the recovery tank (32) through the vacuum pump (43). The mixed phase in the lower gas chamber (48) is separated by the separator (44), and the gas phase enters the recovery tank (32).

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