Three-stage deactivation water washing equipment and deactivation water washing process for ethylene propylene rubber production
Patent Information
- Application Number
- CN202511957775.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-23
- Publication Date
- 2026-10-23
AI Technical Summary
乙丙橡胶反应器出来聚合液，经脱除单体后，仍有部分未反应催化剂残存在溶液中，此部分催化剂如果不进行清除，聚合液在下游工艺系统中仍会有反应进行，且催化剂最终会残存在产品中，影响产品质量
[0028]本发明采用甲醇作为失活剂与催化剂反应，生成可以溶解于水的化合物，经氢氧化钠溶液中和系统中的HCL后，再经设有三级水洗，富含催化剂络合物的废水在此排出工艺系统，在压力作用下这部分水被送到甲醇回收工段进行甲醇回收。通过调整冲洗水温度流量，甲醇的进料量控制洗涤去灰效率。经过三级水洗使聚合物溶液中的催化剂残余彻底脱除，催化剂去除率高，催化剂残留降至<50ppm，使产品达到汽车密封条、高压电缆绝缘层等高端应用标准，产品质量更高。本发明的三级水洗把残留量降低为初始的1‰，甚至更低。二级水洗残留量还高，四级水洗残留量降低很小，但投资成本大幅度提升。
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of chemical production technology, and relates to a chemical apparatus for producing ethylene propylene rubber by polymerization, and a three-stage deactivation water washing process mainly applied after the polymerization reaction in the production of ethylene propylene rubber. Background Technology
[0002] Ethylene-propylene rubber (EPR) is one of the world's seven major synthetic rubbers, ranking third globally in production capacity and consumption, after styrene-butadiene rubber (SBR) and butadiene rubber (BR). The EPR polymerization reaction employs a solution polymerization process with hexane as the solvent. Ethylene, propylene, and dienes copolymerize under the action of a Ziegler-Natta catalyst via a coordination polymerization mechanism. The primary catalyst used is vanadium oxychloride, and the auxiliary catalyst is alkylaluminum. After monomer removal, some unreacted catalyst remains in the polymerization solution exiting the EPR reactor. If this catalyst is not removed, the polymerization will continue in downstream processes, ultimately affecting product quality. Traditional water washing processes use either water or alcohol alone, resulting in low catalyst deactivation and ash removal efficiency. Therefore, a methanol deactivation-three-stage water washing synergistic process is adopted. Summary of the Invention
[0003] This invention addresses the issue that after the monomer is removed from the polymer solution following the ethylene propylene rubber polymerization process, some unreacted catalyst remains in the solution. The invention employs a process of catalyst deactivation and water washing to remove the catalyst residue, thereby improving product quality.
[0004] The first aspect of the present invention discloses a three-stage deactivation washing device for the production of ethylene propylene rubber, comprising an evaporator, a deactivator, a contactor, a first separator, a second separator, a third separator, a pressure reducing valve, a flash tank, a pump, and connecting pipes;
[0005] The evaporator is connected to a deactivator, which is connected to the first separator. The first separator is connected to the second separator, and the second separator is connected to the third separator. The first, second, and third separators are bidirectionally connected. Contactors are installed on the connecting pipes leading from the deactivator to the first, second, and third separators. The third separator is connected to the pressure reducing valve and then to the flash tank.
[0006] The process for producing the ethylene propylene rubber is a solution polymerization process.
[0007] In some embodiments of the present invention, the solution polymerization process is a copolymerization reaction of ethylene, propylene and diene under the action of a Ziegler-Natta catalyst according to a coordination polymerization mechanism;
[0008] Preferably, the main catalyst for the solution polymerization process is vanadium oxychloride, and the auxiliary catalyst is alkylaluminum.
[0009] In some embodiments of the present invention, the deactivator is equipped with a stirring device, the contactor is equipped with a shaft impeller, the third separator is equipped with an angle regulating valve, and the first separator, the second separator, and the third separator are all equipped with centrifugal impellers.
[0010] In some embodiments of the present invention, a methanol recovery device connected to the first separator is also included.
[0011] In some embodiments of the present invention, the systems involved include: a deactivation system and a water washing system.
[0012] The polymer solution from the polymerization stage is continuously added to the deactivator (V-101). Methanol is also continuously added to the deactivator (V-101) with controlled flow. After vaporization in the methanol evaporator, the methanol enters the deactivator (V-101) where its temperature is maintained at 100°C. In the deactivator (V-101), the polymer solution and methanol are fully contacted under stirring. The catalyst reacts with the methanol to convert it into a water-soluble compound. The polymer solution discharged from the bottom of the deactivator (V-101) after the deactivation reaction with methanol undergoes a three-stage water washing process.
[0013] The NaOH aqueous solution added at the inlet of pump (P-101A / B) and the polymer solution are pumped together to contactor (Z-101). The rotation of the drive shaft of contactor (Z-101) drives the impeller to rotate at high speed, generating a rapid and powerful shearing action that agitates the liquid medium, ensuring uniform mixing of the NaOH aqueous solution and the polymer solution, and propelling the fluid medium towards the centrifugal impeller. This two-phase mixing allows the NaOH to neutralize the HCl produced during the deactivation reaction. The polymer solution and NaOH aqueous solution are then conveyed from contactor (Z-101) to the first separator (V-102). In the first separator (V-102), the solution separates into a polymer solution phase and an aqueous phase under gravity, with catalyst residue and methanol transferring from the polymer solution phase to the aqueous phase. This washing process involves a three-stage water washing process in the first separator (V-102), the second separator (V-103), the third separator (V-104), and contactors (Z-101, Z-102, and Z-103). The polymer solution is added to the first separator (V-102) and discharged from the third separator (V-104). NaOH aqueous solution is added to the third separator (V-104) and discharged from the first separator (V-102), with the two reacting in opposite directions to ensure complete removal of catalyst residue from the polymer solution. The aqueous phase containing catalyst residue is discharged from the bottom of the first separator (V-102) and, under pressure, sent to the methanol recovery section. The washed polymer solution is discharged from the top of the third separator (V-104), depressurized by a pressure reducing valve, and then enters the polymer solution flash evaporator (V-105), where some hexane is flashed off to obtain a relatively pure ethylene propylene rubber solution.
[0014] A second aspect of the present invention discloses a three-stage deactivation washing process for the production of ethylene propylene rubber, comprising the following steps:
[0015] S11, deactivate the polymer solution obtained from the production of ethylene propylene rubber; the preferred deactivation temperature is 95-105℃;
[0016] S12, the mixture obtained after the step is washed with water;
[0017] The process for producing the ethylene propylene rubber is a solution polymerization process.
[0018] In some embodiments of the present invention, the solution polymerization process is a copolymerization reaction of ethylene, propylene and diene under the action of a Ziegler-Natta catalyst according to a coordination polymerization mechanism;
[0019] Preferably, the main catalyst for the solution polymerization process is vanadium oxychloride, and the auxiliary catalyst is alkylaluminum.
[0020] In some embodiments of the present invention, S11 involves mixing the polymer solution from the polymerization stage obtained from the production of ethylene propylene rubber with additives, so that the catalyst in the polymer solution reacts and loses its catalytic activity.
[0021] Preferably, the polymer solution from the polymerization stage obtained from the production of ethylene propylene rubber is mixed with vaporized methanol, and the catalyst in the polymer solution reacts with the methanol to convert it into a water-soluble compound.
[0022] In some embodiments of the present invention, S12 is as follows: the polymer solution obtained in step S11 is added from the first separator, passes through the second separator, and is discharged from the third separator; the NaOH aqueous solution is added from the third separator, passes through the second separator, and is discharged from the first separator; the two are in countercurrent contact; the aqueous phase containing catalyst residue is discharged from the bottom of the first separator; and the polymer phase is discharged from the bottom of the third separator.
[0023] Preferably, the operating pressure of the first separator, the second separator, and the third separator is 0.5-0.9 MPa, and the temperature is 80-140℃.
[0024] In some embodiments of the present invention, step S13 is also included: the polymer phase obtained in step S12 is subjected to flash evaporation after being depressurized by a pressure reducing valve, and part of the solvent of the solution polymerization process is flashed off to obtain a relatively pure ethylene propylene rubber solution.
[0025] Preferably, the flash evaporation is performed at a pressure of 0-0.1 MPa and a temperature of 60-90°C.
[0026] In some embodiments of the present invention, S14 is further included: recovering methanol from the aqueous phase obtained in step S12.
[0027] Beneficial effects:
[0028] This invention uses methanol as a deactivating agent to react with a catalyst, generating a water-soluble compound. After neutralizing the HCl in the system with sodium hydroxide solution, the mixture undergoes a three-stage water wash. Wastewater rich in catalyst complexes is discharged from the process system at this stage. Under pressure, this water is sent to the methanol recovery section for methanol recovery. The washing and ash removal efficiency is controlled by adjusting the temperature and flow rate of the rinsing water and the methanol feed rate. The three-stage water wash completely removes catalyst residue from the polymer solution, achieving a high catalyst removal rate and reducing catalyst residue to <50ppm. This allows the product to meet high-end application standards such as automotive sealing strips and high-voltage cable insulation layers, resulting in higher product quality. The three-stage water wash of this invention reduces the residue to 1‰ of the initial level, or even lower. The second-stage water wash still results in a higher residue, and the fourth-stage water wash only slightly reduces the residue, but significantly increases investment costs.
[0029] Therefore, this process is simple, fully functional, safe, and effective, with extremely high applicability and wide application value in ethylene propylene rubber. Attached Figure Description
[0030] Figure 1 This is a schematic diagram of a three-stage deactivation washing process for the production of ethylene propylene rubber according to one embodiment of the present invention. Detailed Implementation
[0031] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.
[0032] In a certain ethylene propylene rubber plant, please refer to the appendix. Figure 1The polymer solution after polymerization is continuously pumped into the deactivator (V-101). Methanol is also continuously added to the deactivator (V-101), with the methanol flow rate controlled. After being vaporized in a methanol evaporator, the methanol enters the deactivator (V-101), and the temperature of the deactivator (V-101) is controlled by the temperature of the methanol to maintain 100°C. In the deactivator (V-101), the polymer solution and methanol are fully contacted under stirring. The catalyst reacts with the methanol to convert it into a water-soluble compound. The polymer solution discharged from the bottom of the deactivator (V-101) after the deactivation reaction with methanol undergoes a three-stage water washing process (the deactivation in the V-101 unit is not considered water washing; the three-stage water washing is performed in tanks V-102, V-103, and V-104). NaOH aqueous solution added at the inlet of pumps (P-101A / B) is pumped together with the polymer solution to the contactor (Z-101). In contactor (Z-101), the NaOH aqueous solution is mixed with the polymer solution, allowing the NaOH to neutralize the HCl produced during the deactivation reaction. The polymer solution and NaOH aqueous solution are then conveyed from contactor (Z-101) to the first separator (V-102). In the first separator (V-102), the solution separates into a polymer solution phase and an aqueous phase under gravity, with residual catalyst and methanol transferring from the polymer solution phase to the aqueous phase. This washing process is carried out in three stages: in the first separator (V-102), the second separator (V-103), the third separator (V-104), and the contactors (Z-101, Z-102, and Z-103). Higher rinse water temperature results in higher descaling efficiency. Since the system temperature at atmospheric pressure is much higher than the boiling point of hexane, a pressure exceeding the hexane vapor pressure must be used. In this system, the polymer solution entering the third separator (V-104) is heated before being mixed with the polymer solution to maintain a temperature of 115°C. The pressure in the third separator (V-104) is controlled at 650 kPa by the opening of an angle regulating valve. The polymer solution is added from the first separator (V-102) and discharged from the third separator (V-104). NaOH aqueous solution is added from the third separator (V-104) and discharged from the first separator (V-102). The two react in opposite directions, ensuring complete removal of catalyst residue from the polymer solution. The aqueous phase containing catalyst residue is discharged from the bottom of the first separator (V-102), which operates at a pressure of 0.6 MPa. Under pressure, this water is sent to the methanol recovery section. The washed polymer solution is discharged from the top of the third separator (V-104), and after being depressurized by a pressure reducing valve, it enters the polymer solution flash evaporator (V-105), where some hexane is flashed off to obtain a relatively pure ethylene propylene rubber solution. The third separator (V-104) operates at a pressure of 0.65 MPa and a temperature of 115 °C, while the polymer solution flash tank (V-105) operates at a pressure of 0.04 MPa and a temperature of 73 °C.
[0033] The preferred embodiments and examples of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments and examples. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the concept of the present invention.
Claims
1. A three-stage deactivation washing device for ethylene propylene rubber production, characterized in that, It includes an evaporator, deactivator, contactor, first separator, second separator, third separator, pressure reducing valve, flash tank, pump, and connecting pipes; The evaporator is connected to a deactivator, which is connected to the first separator. The first separator is connected to the second separator, and the second separator is connected to the third separator. The first, second, and third separators are bidirectionally connected. Contactors are installed on the connecting pipes leading from the deactivator to the first, second, and third separators. The third separator is connected to the pressure reducing valve and then to the flash tank. The process for producing the ethylene propylene rubber is a solution polymerization process.
2. The three-stage deactivation washing equipment for ethylene propylene rubber production according to claim 1, characterized in that, The solution polymerization process involves the copolymerization of ethylene, propylene, and dienes under the action of a Ziegler-Natta catalyst, following a coordination polymerization mechanism. Preferably, the main catalyst for the solution polymerization process is vanadium oxychloride, and the auxiliary catalyst is alkylaluminum.
3. The three-stage deactivation washing equipment for ethylene propylene rubber production according to claim 1 or 2, characterized in that, The deactivator is equipped with a stirring device, the contactor is equipped with a shaft impeller, the third separator is equipped with an angle regulating valve, and the first separator, the second separator, and the third separator are all equipped with centrifugal impellers.
4. The three-stage deactivation washing equipment for ethylene propylene rubber production according to any one of claims 1-3, characterized in that, It also includes a methanol recovery device connected to the first separator.
5. A three-stage deactivation washing process for ethylene propylene rubber production, characterized in that, Includes the following steps: S11, deactivate the polymer solution obtained from the production of ethylene propylene rubber; the preferred deactivation temperature is 95-105℃; S12, the mixture obtained after the deactivation step is washed with water; The process for producing the ethylene propylene rubber is a solution polymerization process.
6. The three-stage deactivation washing process for ethylene propylene rubber production according to claim 5, characterized in that, The solution polymerization process involves the copolymerization of ethylene, propylene, and dienes under the action of a Ziegler-Natta catalyst, following a coordination polymerization mechanism. Preferably, the main catalyst for the solution polymerization process is vanadium oxychloride, and the auxiliary catalyst is alkylaluminum.
7. The three-stage deactivation washing process for ethylene propylene rubber production according to claim 5 or 6, characterized in that, S11 involves mixing the polymer solution from the polymerization stage of ethylene propylene rubber production with additives, causing the catalyst in the polymer solution to react and lose its catalytic activity. Preferably, the polymer solution from the polymerization stage obtained from the production of ethylene propylene rubber is mixed with vaporized methanol, and the catalyst in the polymer solution reacts with the methanol to convert it into a water-soluble compound.
8. The three-stage deactivation washing process for ethylene propylene rubber production according to any one of claims 5-7, characterized in that, S12 is as follows: the polymer solution obtained in step S11 is added from the first separator, passes through the second separator, and is discharged from the third separator; the NaOH aqueous solution is added from the third separator, passes through the second separator, and is discharged from the first separator. The two are in countercurrent contact. The aqueous phase containing catalyst residue is discharged from the bottom of the first separator, and the polymer phase is discharged from the bottom of the third separator. Preferably, the operating pressure of the first separator, the second separator, and the third separator is 0.5-0.9 MPa, and the temperature is 80-140℃.
9. The three-stage deactivation washing process for ethylene propylene rubber production according to any one of claims 5-8, characterized in that, It also includes step S13: the polymer phase obtained in step S12 is subjected to flash evaporation after being depressurized by a pressure reducing valve, and part of the solvent of the solution polymerization process is flashed off to obtain a relatively pure ethylene propylene rubber solution. Preferably, the flash evaporation is performed at a pressure of 0-0.1 MPa and a temperature of 60-90°C.
10. The three-stage deactivation washing process for ethylene propylene rubber production according to any one of claims 5-9, characterized in that, It also includes S14: recovering methanol from the aqueous phase obtained in step S12.