Production process for high-purity polyarylene ether nitrile

Abstract

The present invention relates to the field of the production of polyarylene ether nitrile. Disclosed is a production process for a high-purity polyarylene ether nitrile. The production process comprises a feeding step, a synthesis step, a granulation step and a separation and washing step. In the production process for high-purity polyarylene ether nitrile of the present invention, a solid-liquid mixture obtained after the completion of granulation is subjected to alcohol washing multiple times, and a solvent in a filtering machine is transferred to the bottom of a dealcoholization tower to be rectified and recycled and is then transferred to an alcohol tank of a granulator to be reused, thereby improving the alcohol washing effect; then a solid material obtained from alcohol washing is dried; subsequently, the solid material obtained from alcohol washing is washed with water multiple times, then washed with acid after washing with water, and is then dried; and finally, the solid material is dried, thereby eliminating impurities in a polyarylene ether nitrile product and improving the purity of the polyarylene ether nitrile.

Description

A production process for high-purity polyarylether nitrile Technical Field

[0001] This invention relates to the field of polyarylene ether nitrile production technology, and in particular to a production process for high-purity polyarylene ether nitrile. Background Technology

[0002] Polyarylene ether nitrile (PEEN) is a linear aromatic polymer compound. It is a high-temperature thermoplastic with a high glass transition temperature (175℃) and melting point (353℃), and a heat distortion temperature under load as high as 260℃. It can be used under pressure at 230℃ for extended periods. PEEN resin not only exhibits superior heat resistance compared to other high-temperature plastics, but also possesses high strength, high modulus, high fracture toughness, and excellent dimensional stability. Furthermore, PEEN also possesses excellent self-lubricating properties, ease of processing, stable insulation, and hydrolysis resistance. These characteristics make it widely applicable in industries such as aerospace, automotive manufacturing, electronics, medical, and food processing, with a very promising future for its development and utilization.

[0003] Currently, the purity of polyarylether ether nitrile synthesis is consistently low, for many reasons. One of these reasons is incomplete washing during the separation and washing process: insufficient washing cycles in separation and washing steps such as water washing and drying, and alcohol washing and drying, can lead to impurities such as byproducts and salts generated during the reaction, reducing product purity. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the related art.

[0005] Therefore, the purpose of this invention is to provide a production process for high-purity polyarylene ether nitrile. This invention involves repeatedly washing the solid-liquid mixture after pelleting with alcohol, then repeatedly washing the alcohol-washed solid material with water, and finally acid washing, thereby purifying the impurities in the polyarylene ether nitrile product and improving the purity of the polyarylene ether nitrile.

[0006] To achieve the above objectives, this invention proposes a production process for high-purity polyarylether nitrile, comprising the following steps:

[0007] S1. Feeding process: Dichlorobenzonitrile, hydroquinone, and potassium carbonate are added to the dehydration tank while stirring; then toluene is added to the dehydration tank; NMP is added to the dehydration tank.

[0008] S2. Synthesis process: The temperature inside the dehydration kettle is controlled at 140-150℃, and the dehydration time is 1.5-2.5 hours. The material is then transferred to the polycondensation kettle for polycondensation reaction. Subsequently, the temperature inside the polycondensation kettle is controlled at 185-190℃, and toluene is then removed and cooled. NMP is then injected to clean the polycondensation kettle, and the material is ready for pelleting.

[0009] S3. Pelletizing process: Turn on the methanol pump to inject methanol into the methanol tank of the pelletizer, and then pelletize to form a solid-liquid mixture; after all the material is pelletized, continue to clean the crushed material in the pelletizer by injecting NMP until no more solid material appears in the discharge, and then turn off the pelletizer.

[0010] S4. Separation and washing process: The solid-liquid mixture after pelleting is washed with alcohol, the alcohol-washed solid material is washed with water multiple times, then dried, and finally dried.

[0011] Further, in step S4, the alcohol washing step is as follows:

[0012] S41. Transfer the solid-liquid mixture after pelleting to a filter. First, start the filter and stir. After soaking and extracting for 3-5 hours, transfer the filtrate from the filter to an intermediate tank for alcohol removal solvent. This filtrate will be used for subsequent distillation in the bottom of the dealcoholization tower.

[0013] S42. Pour fresh methanol into the filter until the material is completely soaked in methanol. Stir and soak for 0.5 to 1 hour. Then open the filter and transfer the filtrate to the alcohol washing solvent intermediate tank. This filtrate will be reused after being transferred to the pelletizer alcohol tank through the alcohol washing solvent.

[0014] Further, the alcohol-washed solid material is dried, specifically through the following steps:

[0015] S43. Release the alcohol-washed solid material into the alcohol-washing drying system and wait for drying. Turn on the alcohol-washing vacuum pump and heat the material to dry. When the liquid level in the alcohol-washing drying receiving tank no longer increases, the drying is finished.

[0016] S44. After drying, rake out the solid material in the alcohol washing and drying system and transfer it to the filter. Open the bottom valve of the alcohol washing and drying receiving tank and transfer the received methanol to the alcohol receiving tank of the deethanolating tower.

[0017] Furthermore, in step S4, the multiple water washing steps are as follows:

[0018] S401. Pour fresh water into the filter, slowly add hydrochloric acid to the filter, control the pH value to 7-8, heat to 80℃ and stir for 10 minutes, then stop heating and perform the filtration operation. Put the first washing liquid with the highest salt concentration into the primary washing liquid tank for reuse. In the later stage of filtration, open the nitrogen valve and use nitrogen to pressurize the filter. Repeat the above several times, and then pressurize the filter to the secondary washing liquid tank for reuse.

[0019] Furthermore, the material after multiple washes is subjected to acid pickling, the specific steps of which are as follows:

[0020] S402. Starting with the material to be pickled, the water used is the recycled water in the primary washing liquid tank. The recycled water is pumped into the filter, and hydrochloric acid is slowly added to the filter. The pH value is controlled at 7-8. After heating to 80°C, it is stirred for 10 minutes. Then, the heating is stopped, and the filter is carried out while it is hot. The waste brine is put into the primary washing liquid tank for filtration, and then filtered with nitrogen pressure. After the pressure filtration is completed, the recycled water is pumped into the waste brine feed tank for subsequent salt distillation treatment.

[0021] S403. Multiple washing: Pour water into the filter press, soak for 0.5 to 1 hour, then pressurize with nitrogen to filter. Use the filter press to make a washing liquid tank for reuse, and repeat this process multiple times.

[0022] Furthermore, in step S4, the solid material drying step is as follows:

[0023] S4001. Place the wet material in the filter into the product drying system and wait for it to dry; turn on the product drying system and maintain the inner drying temperature at 120-130℃.

[0024] S4002. Start the product drying system, dry at 105-120℃ for two hours, measure the remaining moisture content of the dried product, control the water mass ratio to ≤0.5%, and stop drying.

[0025] S4003. Turn on the product drying system and transfer the polyarylether nitrile material to the mixer for temporary storage.

[0026] Beneficial effects: This invention improves the alcohol washing effect by subjecting the solid-liquid mixture after pelleting to multiple alcohol washings, transferring the solvent from the filter to the bottom of the de-alcoholizing tower for distillation and reuse in the pelletizer's alcohol tank, and then drying the alcohol-washed solid material. The alcohol-washed solid material is then subjected to multiple water washings, followed by acid washing, and then drying. Finally, the solid material is dried, thus purifying the impurities in the polyarylene ether nitrile product and improving its purity.

[0027] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Detailed Implementation

[0028] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the scheme, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the scheme are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0029] The production process of high-purity polyarylene ether nitrile according to embodiments of the present invention will be described below with reference to the scheme.

[0030] The production process of polyarylene ether nitrile is as follows:

[0031] I. Feeding Process

[0032] Inspection and preparation: Before feeding materials after the first start-up or after the application is completed, carefully check that all pipes and valves are in normal working order, that there are no leaks in the pipe flanges, and that the instruments are in normal working order before feeding materials.

[0033] The material is fed into the dehydration kettle; the agitator and feed inlet butterfly valve of the dehydration kettle are opened, the vacuum feeder P401 and the vacuum pump are turned on, and the metered ton bags of dichlorobenzonitrile, hydroquinone and potassium carbonate are fed into the dehydration kettle while stirring (potassium carbonate is added first to fill the bottom outlet of the kettle to short-circuit the dead corner). After the material is fed, the feed inlet butterfly valve is closed.

[0034] Toluene addition (initial start-up): Turn on the toluene pump and toluene feed pump in the tank area, and simultaneously open the inlet shut-off valve of the toluene metering tank to pump toluene into the toluene metering tank for metering. After metering is completed, turn off the feed pump and shut-off valve, and open the outlet bottom valve of the toluene metering tank to add toluene into the dehydration reactor.

[0035] Upon initial start-up or completion of distillation, NMP (short for N-methylpyrrolidone) is added: Turn on the NMP pump in the tank area; upon completion of distillation, turn on the NMP feed pump and simultaneously open the inlet shut-off valve of the NMP metering tank to inject NMP into the metering tank for metering. After metering is complete, turn off the feed pump and shut-off valve, and open the outlet bottom valve of the NMP metering tank to add NMP to the dehydration reactor.

[0036] II. Synthesis Process

[0037] Dehydration kettle temperature rise and reaction control: Open the inlet shut-off valve and outlet valve of the heat transfer oil in the dehydration kettle, and adjust the oil temperature of the heat transfer oil regulating valve to 175℃, so that the liquid phase temperature in the dehydration kettle slowly rises to 145℃. After the material begins to react and produce water and carbon dioxide, open the circulating water ball valve of the dehydration kettle condenser and the inlet ball valve of the dehydration reflux separator for condensation reflux. At the same time, adjust the heat transfer oil regulating valve to control the temperature inside the dehydration kettle at 140-150℃, and dehydrate for 2.5 hours. When the water level in the separator no longer increases, open the bottom insulation ball valve and nitrogen valve of the dehydration kettle to transfer the material to the polycondensation kettle.

[0038] Polycondensation reactor reaction and toluene handling: Open the inlet shut-off valve and outlet valve of the heat transfer oil in the polycondensation reactor, and adjust the oil temperature of the heat transfer oil regulating valve to 205℃, so that the temperature inside the polycondensation reactor is controlled at around 185℃. Open the circulating water ball valve of the condensation reactor condenser and the inlet ball valve of the polycondensation reflux water separator to collect toluene for 1 hour. Then open the outlet ball valve of the polycondensation reflux water separator to distill the toluene and collect it in the toluene receiving tank for natural cooling. After the toluene drops to room temperature, open the bottom ball valve to recover it to the toluene recovery tank (replenishment can be made when the liquid level in the toluene recovery tank is below 50%).

[0039] After all the heat transfer oil has been extracted, adjust the regulating valve to raise the temperature to 185–190°C and maintain this temperature for 2 hours. Observe the viscosity change in real time and take samples to test the intrinsic viscosity. Adjust the rotation speed according to the viscosity change. After the viscosity count value and current value stabilize, add an appropriate amount of NMP to terminate the reaction.

[0040] Polycondensation reactor cleaning and material transfer: After the reaction in the polycondensation reactor is complete, open the heat transfer oil shut-off valve of the buffer reactor and adjust the heat transfer oil regulating valve to control the temperature inside the buffer reactor to approximately 135℃. Open the nitrogen valve and bottom insulation valve of the polycondensation reactor to temporarily store the material in the buffer reactor. Next, open the valve of the spray device on the polycondensation reactor and the NMP cleaning pump to spray the reactor wall with NMP. After the cleaned reactor liquid is discharged into the buffer reactor, stop spraying, close the discharge valve of the polycondensation reactor, and wait for the pelletizer to be debugged before sending the material to the next process.

[0041] III. Pelletizing process

[0042] Methanol Circulation and Pelletizing Preparation (Initial Start-up or Distillation Completion): For initial start-up, turn on the methanol pump in the tank area to fill the methanol recovery tank of the dehydrogenator. After distillation, turn on the methanol feed pump of the dehydrogenator and simultaneously open the inlet ball valve of the pelletizer's methanol tank to fill it. Turn on the pelletizer's methanol pump to add methanol to the settling tank to maintain a suitable liquid level. Open the cooling water valves on the circulating feed pump and the methanol heat exchanger to cool the methanol before introducing it into the intermediate methanol tank. After a vortex forms in the buffer vessel at the inlet of the pulverizer, turn on the pulverizer to pump methanol to the filters (a, b). After being filtered by the filters, the methanol enters the settling tank to form a methanol circulation loop. Adjust the pulverizer parameters to maintain a constant liquid level in the buffer vessel at the inlet of the pulverizer. Open the insulation valve at the bottom of the buffer vessel and the nitrogen valve at the top to feed the pelletizer.

[0043] Material crushing speed adjustment: The material crushing speed is adjusted by adjusting the feed valve of the inlet buffer tank of the crusher. While ensuring that the pipeline from the crusher to the two-in-one filter is not blocked, more material is fed to increase the crushing speed.

[0044] Filtrate treatment and filter switching: Open the discharge valve on the south side of the bottom of the two-in-one filter to filter the filtrate from the solid-liquid mixture after pelleting into the settling tank below for further pelleting. Observe the filtration status of filter a through the sight glass. When the filter is almost full, adjust the valve to guide the material to filter b for filtration.

[0045] Pelletizing End Operation: After the material in the buffer tank is pelletized, open the NMP feed pipe valve, the valve of the upper spray system of the buffer tank, and the NMP cleaning pump. Continue the crushing operation with NMP until no more solid material appears in the sight glass of the crusher outlet. Then, close the pelletizer, the pelletizer heat transfer oil valve, and the bottom butterfly valve of the solid-liquid separator. Empty the methanol in the settling tank and add fresh methanol as needed to flush the methanol heat exchanger, pelletizer, and solid-liquid separator. Finally, the material enters the two-in-one filter.

[0046] IV. Separation and Washing Process

[0047] Alcohol washing and drying:

[0048] First alcohol wash: After the solid-liquid mixture after pelleting is transferred to filters a and b, start the stirring of filter a, soak and extract for 3 hours, open the filtrate outlet valve on the side of the filter and the nitrogen valve on the top, transfer the filtrate to the alcohol-cure solvent intermediate tank, and then transfer it to the bottom of the de-alcoholization tower for distillation and reuse.

[0049] Second alcohol wash: Turn on the pelletizer alcohol pump to pump fresh methanol into filters a and b until the material is completely soaked in methanol. Turn on the agitator and soak for 0.5 hours. Then, open the filtrate outlet valve on the side of the filter and the nitrogen valve on the top to transfer the filtrate to the alcohol wash solvent intermediate tank. After that, the filtrate is transferred to the pelletizer alcohol tank by the alcohol wash solvent feed pump and then reused.

[0050] Drying: The alcohol-washed solid material is discharged through the side discharge valve into the alcohol washing and drying system below. Open the gas phase valve, cooling water valve of the alcohol washing and drying condenser, inlet valve of the alcohol washing and drying receiving tank, and vacuum pipeline valve of the alcohol washing and drying system. Turn on the alcohol washing vacuum pump to put the drying system into a vacuum state. Then open the steam inlet valve and steam condensate outlet valve of the alcohol washing and drying system to heat the material to be dried. When the liquid level in the alcohol washing and drying receiving tank no longer increases, the drying is over.

[0051] Material transfer and methanol recovery: After drying, close the inlet valve of the alcohol washing vacuum buffer tank, open the vent valve of the alcohol washing drying receiving tank, rake out the solid material in the alcohol washing drying system, manually transfer it to filter b, open the bottom valve of the alcohol washing drying receiving tank, and transfer the received methanol to the methanol receiving tank of the deethanolating tower.

[0052] Water washing and drying (using fresh water from the brine recovery tank for initial startup): Initial startup acid washing and filtration: Open the bottom valve of the tank and the brine feed pump to pump fresh water into filter c or filter d (the liquid level should just submerge the material). Open the filter agitator and the discharge valve of the hydrochloric acid metering tank. Slowly add hydrochloric acid to filter c or d. After the system is neutralized (the liquid surface stops bubbling) and the pH value is 7-8, close the discharge valve of the hydrochloric acid metering tank. After the sample analysis is qualified, open the steam inlet valve of the filter while stirring, heat to 80°C and stir for 10 minutes. Then stop heating and perform the filtration operation.

[0053] Primary washing liquid treatment: Open the valve leading to the primary washing liquid tank in the filtrate discharge valve on the side of filter C or filter D, and put the washing liquid with the highest salt concentration in the first batch into the primary washing liquid tank for reuse. In the later stage of filtration, open the nitrogen valve to filter with nitrogen gas. After the pressure filtration is completed, close the valve leading to the primary washing liquid tank.

[0054] Secondary washing: Open the bottom valve of the brine recovery tank and the brine feed pump to pump fresh water into filter c or filter d (the liquid level should just submerge the material). While stirring, wash and soak for 0.5 hours, then pressurize with nitrogen. Open the valve in the filtrate discharge valve that leads to the secondary washing liquid tank to pressurize the filtrate into the secondary washing liquid tank. After filtration is complete, close the valve.

[0055] Three washing steps: Open the bottom valve of the brine recovery tank and the brine feed pump to pump fresh water into filter c or filter d (the liquid level should just submerge the material). While stirring, wash and soak for 0.5 hours, then pressurize with nitrogen. Open the valve in the filtrate discharge valve that leads to the three washing liquid tank to pressurize the filtrate into the three washing liquid tank. After filtration is complete, close the valve.

[0056] Fourth washing: Open the bottom valve of the brine recovery tank and the brine feed pump to pump fresh water into filter c or filter d (the liquid level should just submerge the material). While stirring, wash and soak for 0.5 hours, then pressurize with nitrogen. Open the valve in the filtrate discharge valve that leads to the fourth washing liquid tank to pressurize the filtrate into the fourth washing liquid tank. After filtration is complete, close the valve.

[0057] Pickling (starting from the second batch of materials): Open the bottom valve of the tank and the primary washing liquid pump, and pump the jacket water into filter C or filter D (the liquid level should just submerge the material). Open the filter agitator and the discharge valve of the hydrochloric acid metering tank, and slowly add hydrochloric acid to filter C or D. After the system is neutralized to a pH of 7-8, close the discharge valve of the hydrochloric acid metering tank. After the sample analysis is qualified, open the steam inlet valve of the filter while stirring, heat to 80°C and stir for 10 minutes, then stop heating and perform filtration while hot. Open the valve on the side of filter C or filter D that leads to the primary washing liquid tank, and put the waste brine into the primary washing liquid tank. In the later stage of filtration, open the nitrogen valve to use nitrogen for pressure filtration. After the pressure filtration is completed, close the valve leading to the primary washing liquid tank, open the primary washing liquid pump, and pump the jacket water into the waste brine feed tank for salt distillation treatment.

[0058] First wash (subsequent batches): Open the bottom valve of the secondary wash liquid tank and the secondary wash liquid pump, and pump the water into filter c or filter d (the liquid level should just submerge the material). While stirring, wash and soak for 0.5 hours, then pressurize with nitrogen. Open the valve in the filtrate discharge valve that leads to the primary wash liquid tank, pressurize the filtrate into the primary wash liquid tank, and close the valve after filtration is complete.

[0059] Secondary washing (subsequent batches): Open the bottom valve of the tertiary washing liquid tank and the tertiary washing liquid pump, and pump the water into filter c or filter d (the liquid level should just submerge the material). While stirring, wash and soak for 0.5 hours, then pressurize with nitrogen. Open the valve in the filtrate discharge valve that leads to the secondary washing liquid tank, pressurize the filtrate into the secondary washing liquid tank, and close the valve after filtration is complete.

[0060] Three washes (subsequent batches): Open the bottom valve of the fourth wash liquid tank and the fourth wash liquid pump, and pump the water into filter c or filter d (the liquid level should just submerge the material). While stirring, wash and soak for 0.5 hours, then pressurize with nitrogen. Open the valve in the filtrate discharge valve that leads to the third wash liquid tank, pressurize the filtrate into the third wash liquid tank, and close the valve after filtration is complete.

[0061] Fourth washing (subsequent batches): Open the bottom valve of the brine recovery tank and the brine feed pump to pump fresh water into filter c or filter d (the liquid level should just submerge the material). While stirring, wash and soak for 0.5 hours, then pressurize with nitrogen. Open the valve in the filtrate discharge valve that leads to the fourth washing liquid tank to pressurize the filtrate into the fourth washing liquid tank. After filtration is complete, close the valve.

[0062] V. Drying Process

[0063] Material drying preparation: Put the wet material in filter c or d into the product drying system below through the discharge valve, open the steam regulating valve and steam inlet switch valve of the product drying system, and maintain the drying temperature of the inner chamber at 120℃.

[0064] Drying operation and moisture control: Start the product drying system and dry the product until the remaining moisture meets the requirements (measure the moisture content in the oven at 105℃ for two hours, with a water mass ratio of ≤0.5%, and the optimal value being 0.1%).

[0065] Gas Phase Processing and Material Transfer: During the drying process, the gas phase enters the exhaust manifold after passing through the collector. Open the bottom discharge port of the product drying system to temporarily transfer the polyarylether nitrile material to a conical mixer. If the customer has special requirements, additives can be added to the mixer for thorough mixing before granulation; otherwise, it can be packaged and shipped directly.

[0066] In summary, the production process of high-purity polyarylether nitrile in this embodiment of the invention improves the alcohol washing effect by subjecting the solid-liquid mixture after pelleting to multiple alcohol washings, transferring the solvent in the filter to the bottom of the de-alcoholizing tower for distillation and reuse, and reusing it in the pelletizer's alcohol tank. The alcohol-washed solid material is then dried; subsequently, it undergoes multiple water washings, followed by acid washing, and then drying. Finally, the solid material is dried, thus purifying the impurities in the polyarylether nitrile product and improving its purity.

[0067] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A production process for high-purity polyarylether nitrile, characterized in that, The process includes the following steps: S1. Feeding process: Dichlorobenzonitrile, hydroquinone, and potassium carbonate are added to the dehydration tank while stirring; then toluene is added to the dehydration tank; NMP is added to the dehydration tank. S2, Synthesis Process: The materials are transferred to a polycondensation reactor for polycondensation reaction; then toluene is collected and cooled; subsequently, NMP is injected to clean the polycondensation reactor; S3. Pelletizing process: Turn on the methanol pump to inject methanol into the methanol tank of the pelletizer, and then pelletize to form a solid-liquid mixture; after all the material is pelletized, continue to clean the crushed material in the pelletizer by injecting NMP until no more solid material appears in the discharge, and then stop pelletizing. S4. Separation and washing process: The solid-liquid mixture after pelleting is washed with alcohol, the alcohol-washed solid material is washed with water multiple times, then dried, and finally dried.

2. The production process of high-purity polyarylene ether nitrile according to claim 1, characterized in that, In step S4, the alcohol washing step is as follows: S41. Transfer the solid-liquid mixture after pelleting to a filter. First, start the filter and stir. After soaking and extracting for 3-5 hours, transfer the filtrate from the filter to an intermediate tank for alcohol removal solvent. This filtrate will be used for subsequent distillation in the bottom of the dealcoholization tower. S42. Pour fresh methanol into the filter until the material is completely soaked in methanol. Stir and soak for 0.5 to 1 hour. Then open the filter and transfer the filtrate to the alcohol washing solvent intermediate tank. This filtrate will be reused after being transferred to the pelletizer alcohol tank through the alcohol washing solvent.

3. The production process for high-purity polyarylene ether nitrile according to claim 2, characterized in that, The solid material after alcohol washing is dried, and the specific steps are as follows: S43. Discharge the alcohol-washed solid material into the alcohol-washing drying system to await drying. Turn on the alcohol-washing vacuum pump to heat and dry the material. Drying is complete when the liquid level in the alcohol-washing drying receiving tank stops increasing. S44. After drying, rake out the solid material in the alcohol washing and drying system and transfer it to the filter. Open the bottom valve of the alcohol washing and drying receiving tank and transfer the received methanol to the alcohol receiving tank of the deethanolating tower.

4. The production process for high-purity polyarylene ether nitrile according to claim 1, characterized in that, In step S4, the multiple water washing steps are as follows: S401. Pour fresh water into the filter, slowly add hydrochloric acid to the filter, control the pH value to 7-8, heat to 80℃ and stir for 10 minutes, then stop heating and perform the filtration operation. Put the first washing liquid with the highest salt concentration into the primary washing liquid tank for reuse. In the later stage of filtration, open the nitrogen valve and use nitrogen to pressurize the filter. Repeat the above several times, and then pressurize the filter to the secondary washing liquid tank for reuse.

5. The production process for high-purity polyarylene ether nitrile according to claim 4, characterized in that, The material, after multiple washes, is then pickled. The specific steps are as follows: S402. Starting with the material to be pickled, the water used is the recycled water in the primary washing liquid tank. The recycled water is pumped into the filter, and hydrochloric acid is slowly added to the filter. The pH value is controlled at 7-8. After heating to 80°C, it is stirred for 10 minutes. Then, the heating is stopped, and the filter is carried out while it is hot. The waste brine is put into the primary washing liquid tank for filtration, and then filtered with nitrogen pressure. After the pressure filtration is completed, the recycled water is pumped into the waste brine feed tank for subsequent salt distillation treatment. S403. Multiple washing: Pour water into the filter press, soak for 0.5 to 1 hour, then pressurize with nitrogen to filter. Use the filter press to make a washing liquid tank for reuse, and repeat this process multiple times.

6. The production process of high-purity polyarylene ether nitrile according to claim 1, characterized in that, In step S4, the solid material drying step is as follows: S4001. Place the wet material in the filter into the product drying system and wait for it to dry; turn on the product drying system and maintain the inner drying temperature at 120-130℃. S4002. Start the product drying system, dry at 105-120℃ for two hours, measure the remaining moisture content of the dried product, control the water mass ratio to ≤0.5%, and stop drying. S4003. Turn on the product drying system and transfer the polyarylether nitrile material to the mixer for temporary storage.