WO2024139502A1 - High-whiteness and low-impurity-content polyarylether and preparation method therefor - Google Patents

Abstract

The present invention relates to the field of polymer synthesis, and relates to a high-whiteness and low-impurity-content polyarylether and a preparation method therefor. The present invention provides a preparation method for high-whiteness and low-impurity-content polyarylether. The preparation method comprises the following steps: 1) performing a dehydration reaction; 2) first-time solvent recycling; 3) performing solvent recycling and resin purification by means of an extraction method; 4) performing auxiliary agent recycling, resin washing, and washing water purification; and 5) electrolyzing sodium chloride. Compared with traditional processes, the method of the present invention can greatly improve the purity and whiteness of obtained resin, the whiteness being greater than or equal to 85, and the impurity content (comprising volatile matter and ash content) being less than or equal to 12 ppm, and is more conducive to product purification and adaptation to subsequent application requirements in high-end fields; and as high-grade resin, the invention fills a gap domestically and is used for preparing high-quality workpieces such as special thermoplastic composite materials for large aircrafts and special materials for radars and stealth aircraft parts, achieving the effects of reducing costs and improving efficiency.

Description

A kind of polyarylether with high whiteness and low impurity content and preparation method thereof Technical Field

The invention relates to a polyarylether with high whiteness and low impurity content and a preparation method thereof, belonging to the field of polymer synthesis.

Background technique

Polyarylether mainly includes polyphenylene sulfide, polyphenylene sulfide ester, polyphenylene sulfide ketone, polyphenylene sulfide sulfone, polyphenylene sulfide amide, polyphenylene ether sulfide, and polyphenylene sulfide imide. Due to its corrosion resistance, high temperature, excellent electrical properties, mechanical properties, and dimensional stability, it is widely used in aerospace and electronic technology.

Among them, the main production method of polyarylether is: using auxiliary agents, nucleophilic reagents (such as sulfides), dihalogenated aromatic compounds and polar solvents as raw materials, carrying out solution polycondensation, separating the reaction mixture into solid and liquid after the reaction, and purifying the crude resin product by washing with water. The process flow is long and the amount of water used in this process is large. The subsequent solvent is generally recovered by distillation separation, which leads to high energy consumption in the subsequent solvent recovery process and low purity of the recovered solvent. The solvent and volatile content contained in the resin are high, and the resin is impure, which makes the resin dark in color, produces bubbles or defects after being processed into products, affecting the comprehensive performance of the final product. In addition, the separation and recovery of the additives involved are also carried out in aqueous solution, which makes the recovery process energy-intensive and the purity low. Generally, chemical precipitation recovery and separation are required, and then an additional second step of reaction is required to obtain the additives required for the final reaction. The entire process is long and requires a lot of equipment investment, which has led to the high production cost of polyarylether products for a long time. More importantly, its wastewater and waste residue are often difficult to separate completely. For example, the by-product NaCl cannot be recycled later because it contains a large amount of ammonia nitrogen and organic matter, resulting in a large amount of hazardous waste, high cost, and great environmental pressure, which is not conducive to large-scale industrial production.

Summary of the invention

In view of the above-mentioned defects, the present invention provides a method for preparing a high-whiteness, low-impurity polyarylether with recyclable resources. The method is characterized in that sulfide and dichloroaromatic compound are used as raw materials, and purification and solvent recovery are carried out through solution polycondensation reaction and high-temperature filtration and extraction process, and organic solvent leaching and recovery of auxiliary agents are used to prepare a high-purity, high-whiteness, low-impurity polyarylether with recyclable resources; in addition, through the above-mentioned series of purification methods, the obtained salt-containing wastewater can be subjected to deep oxidation treatment to remove organic matter and ammonia nitrogen, and then electrolysis is carried out under the action of an electrolytic catalyst, and the obtained caustic soda and chlorine enter the pre-polymerization reaction and the preparation of dichloromonomers, and hydrogen is recycled as clean energy, thereby achieving complete resource circulation and improving product quality and efficiency.

The technical solution of the present invention:

The technical problem to be solved by the present invention is to provide a method for preparing polyarylether with high whiteness and low impurity content, the preparation method comprising the following steps:

1) Dehydration reaction: adding sulfide, auxiliary agent and solvent into a reaction kettle, and performing dehydration reaction under the protection of nitrogen or inert gas to obtain a dehydrated reaction solution, and sending the removed solvent-containing mixed liquid into a dehydration condensate tank for centralized treatment; after cooling the dehydrated reaction solution, reacting with a dichloro aromatic compound to obtain a reaction product mixed liquid;

2) First solvent recovery: The reaction product mixture obtained in step 1) is filtered at high temperature at 150-220° C. to recover part of the solvent in the reaction product mixture, and the recovered solvent is transported to a solvent recovery tank and directly used for the next batch of material polymerization;

3) Extraction method for solvent recovery and resin purification: cool the filtered material in step 2) to 10-160°C and send it to an extraction kettle, add extractant in batches, and extract the remaining solvent in batches under closed conditions at a temperature of 10-160°C and a pressure of 0-1MPa; filter the extracted mixed solution and send it to a rich extractant mixed liquid tank, and mix it with the solvent-containing mixed liquid in step 1) in proportion, and then extract it by centrifugation or countercurrent tower; then send the mixed liquid containing solvent and extractant to the solvent/extractant tank, and send water to the washing water tank; and separate the mixed liquid containing solvent and extractant by distillation, and recover the extractant and solvent respectively for recycling;

4) Reagent recovery, resin washing and washing water purification: the solid resin crude product obtained after the treatment in step 3) is subjected to the recovery and separation of the additive using an additive leaching agent; the liquid after the leaching is subjected to multi-effect evaporation, the liquid is recovered and used as the next batch of additive leaching agent, and the solid is the recovered additive, which can be used directly without post-treatment; the solid resin crude product after the leaching is subjected to countercurrent washing and solid-liquid separation using desalted water or washing water from the previous batch of products, and the separated water-containing polyarylether resin is vacuum dried to obtain polyarylether with high whiteness and low impurity content; and the washing water is sent to the washing water tank to be hydrated with the extraction separation in step 3) and then an oxidant is added for oxidation treatment to remove organic matter and ammonia nitrogen impurities in the washing water so that it meets the working condition requirements of electrolysis;

5) Sodium chloride electrolysis: After the treatment in step 4), a qualified sodium chloride aqueous solution is obtained, which is placed in an electrolytic cell and converted into sodium hydroxide, chlorine and hydrogen under the action of an electrolytic catalyst; the sodium hydroxide is sold as caustic soda or used in the front-end polymerization reaction of polyarylether resin, the chlorine is used to produce the raw materials p-dichlorobenzene or 4,4'-dichlorodiphenyl sulfone in the production of polyarylether (such as typical resins such as polyphenylene sulfide, polyarylether sulfone, etc.), and the hydrogen is recycled as a clean energy;

Wherein, each raw material is composed of the following components in parts by weight:

Furthermore, in the above preparation method, the method of step 1) is: adding the sulfide, the auxiliary agent and the solvent into a reaction kettle, and carrying out a dehydration reaction at a temperature of 140 to 230° C. for 0.5 to 3 hours under nitrogen protection to obtain a dehydrated reaction solution, and the removed solvent-containing mixed liquid is sent to a dehydration condensate tank for combined centralized treatment; when the temperature of the above reaction solution drops to 80 to 180° C., adding a dichloro aromatic compound, reacting at a temperature of 150 to 230° C. for 0.5 to 8 hours, and then maintaining at a temperature of 230 to 280° C. for 0.5 to 10 hours to obtain a reaction product mixed liquid.

Further, the sulfide is selected from the following compounds:

Either Na2S or NaHS;

The structural formula of the dihalogenated aromatic compound is Cl-Ar-Cl, wherein:

At least one of , wherein m=2, 4, 6, 8 or 10.

Further, in step 1), the solvent is at least one of formamide, acetamide, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, N,N-dimethylpropylene urea, 1,3-dimethyl-2-imidazolidinone, N-cyclohexylpyrrolidone, hexamethylphosphoric triamide, cyclopentane, diphenyl sulfone, ε-caprolactam, dimethyl sulfoxide, dimethyl sulfone, quinoline, isoquinoline, 2,4-dimethylcyclopentane or N-methylcaprolactam; or the solvent is a high-purity solvent with a purity of ≥99% recovered in step 3) of the preparation method.

Further, in step 1), the auxiliary agent is lithium hydroxide, sodium hydroxide, potassium hydroxide, magnesium hydroxide, Calcium, barium hydroxide, aluminum hydroxide, lithium carbonate, sodium carbonate, potassium carbonate, magnesium carbonate, calcium carbonate, barium carbonate, lithium bicarbonate, sodium bicarbonate, potassium bicarbonate, magnesium bicarbonate, calcium bicarbonate, barium bicarbonate, lithium acetate, sodium acetate, potassium acetate, lithium benzoate, sodium benzoate, lithium ethylenediaminetetraacetate, sodium ethylenediaminetetraacetate, trisodium ethylenediaminetetraacetate, potassium ethylenediaminetetraacetate, tripotassium ethylenediaminetetraacetate, sodium dodecylbenzenesulfonate, sodium p-toluene benzoate, lithium p-toluene benzoate, sodium terephthalate, sodium terephthalate, sodium p-toluenesulfonate, sodium p-aminobenzenesulfonate, sodium oxalate, At least one of lithium oxalate, sodium succinate, lithium succinate, sodium adipate, lithium adipate, lithium chloride, sodium phosphate, lithium phosphate, sodium tartrate, lithium tartrate, potassium tartrate, sodium alginate, sodium gluconate, sodium lactate, sodium sorbate, potassium sorbate, sodium lysine, potassium lysine, sodium cystine, sodium 6-aminocaproate, sodium heptanoate, sodium laurate, sodium citrate, sodium glycocholate, dioctyl sodium succinate, sodium ethylenediaminetetramethylenephosphate, sodium diethylenetriaminepenta(methylenephosphonate), sodium aminetri(methylenephosphate), dodecyltriethylammonium chloride, dodecyldimethylammonium bromide or sodium stearate;

Furthermore, in step 3) of the above preparation method, the volume ratio of the mixed solution after extraction to the solvent-containing mixed solution in step 1) is: 1 to 5 parts: 1 to 3 parts.

Further, in step 3), the extractant is any one of chloroform, dichloromethane, tetrachloroethane, carbon tetrachloride, cyclohexane, ethyl acetate, butyl acetate or isopropyl ether.

Furthermore, in step 3), divided into batches means divided into 1 to 5 batches.

Furthermore, in step 4) of the above method, the method of using an auxiliary agent extracting agent to recover and separate the auxiliary agent is as follows: 100 parts of the crude solid resin product obtained in step 3) and 300-3000 parts of the auxiliary agent extracting agent are added to an auxiliary agent extractor for continuous spray countercurrent transmission extraction, the rotation speed of the extractor is 2-30 r/min, the extraction temperature is 20-80° C., and the extraction time is 1-60 min; the resin after extraction is discharged from the upper outlet of the extractor into a centrifuge for solid-liquid separation, and the liquid extracting agent is sent to a feed buffer tank of a multiple-effect evaporator; the liquid part after extraction overflows from the lower outlet of the extractor and is also sent to the feed buffer tank of the multiple-effect evaporator, and then sent to the multiple-effect evaporator for evaporation at 40-90° C. and a vacuum degree of 0.04-0.09 MPa, the liquid after multiple-effect evaporation is recovered and used directly as the next batch of auxiliary agent extracting agent, and the solid after multiple-effect evaporation is recovered and used directly as an auxiliary agent.

Furthermore, in step 4) of the above method, the crude solid resin product after leaching is subjected to countercurrent washing and solid-liquid separation 3 to 5 times, each time with 300 to 1000 parts of desalted water or washing water from the previous batch of products, to remove the salt and a very small amount of additives contained in the product. The separated aqueous polyarylether resin is dried at a temperature of 80 to 120° C. and a vacuum degree of 0.03 to 0.095 MPa for 1 to 12 hours to obtain a resource-recyclable high-purity polyarylether resin; and the washing water is sent to the washing water tank and the extracted separation water in step 3) and oxidized at room temperature to 60° C. under the action of an oxidant to remove organic matter and ammonia nitrogen impurities in the washing water to meet the electrolytic purity requirements.

Further, in step 4) of the above method, the auxiliary leaching agent is at least one of methanol, ethanol, propanol, ethylene glycol, propylene glycol, glycerol, isopropanol, isobutanol, tert-butanol, n-butanol, n-pentanol, isopentanol, n-hexanol, n-heptanol, n-octanol, isooctyl alcohol, acetone, butanone, cyclopentanone, cyclohexanone, chloroform, dichloromethane, tetrachloroethane or carbon tetrachloride.

Furthermore, in step 5) of the above method, the washing water oxidant is at least one of hydrogen peroxide, ozone, Fenton's reagent or ferric chloride.

Furthermore, in step 5) of the above method, the sodium chloride aqueous solution electrolysis catalyst is at least one of ruthenium oxide, yttrium oxide, cerium oxide, lanthanum oxide, titanium dioxide or iridium oxide.

The second technical problem to be solved by the present invention is to provide a polyarylether prepared by the above method.

Furthermore, the whiteness of the polyarylether is ≥85.

Furthermore, the impurity content of the polyarylether is ≤12ppm.

Furthermore, the purity of the polyarylether is ≥99.9%.

In the present invention, the parts of the raw materials are all parts by weight unless otherwise specified.

Beneficial effects of the present invention:

1. In the preparation process of the polyarylether resin of the present invention, a specific extractant and extraction method are used to extract and purify the resin after filtering the solvent, which can achieve two goals at one stroke. The solvent contained in the resin can be recovered and the recovery rate of the solvent can be improved. At the same time, the oxidation and escape of heat-sensitive substances such as solvents contained in the crude resin product can be effectively prevented. The volatile components contained in the resin can be fully eluted and replaced by using the extractant to exchange with the solvent and the resin molecules at the molecular level. As a result, the purity and whiteness of the obtained resin are greatly improved compared with the traditional process, with a whiteness of ≥85; the impurity content (including volatile components and ash) is ≤12ppm; it is more conducive to the purification of the product and to adapt to the application requirements of subsequent high-end fields. As a high-grade resin, it fills the domestic gap and is used to prepare high-quality parts such as special materials for thermoplastic composite materials for large aircraft, special materials for radar and some parts of stealth aircraft, etc., so as to reduce costs and improve efficiency.

2. During the extraction process of the resin of the present invention by the extractant, the auxiliary agent is also purified, so that the subsequent recovery process of the auxiliary agent is simplified, the recovery rate of the auxiliary agent is high, and the purity of the recovered auxiliary agent is as high as 99.5%, and it can be directly reused without any treatment.

3. The present invention can directly use high-temperature filtration solvent or extraction recovery solvent as the reaction solvent, without the need for subsequent dehydration and other refining processes, and the process flow is short; and in the extraction process, extraction and separation are combined into one, the operation is flexible and easy to control, the extractant is an organic matter with small specific heat and low boiling point, the recovery rate is high, the energy consumption is low, and the cost is saved.

4. Compared with the traditional polyarylether preparation process, the functions of subsequent waste liquid and solid waste are clear, the components are separated from each other and deeply purified, the by-product components are separated thoroughly and have high purity, especially the by-product NaCl, the process of removing ammonia nitrogen and organic matter, which is almost completely recovered and recycled by electrolysis, the three wastes are extremely low, and the environmental pressure is small; this is the production in the prior art.

Description of the drawings:

FIG. 1 is an infrared spectrum of the polyphenylene sulfide resin obtained in Example 1.

FIG. 2 is an infrared spectrum of the polyphenylene sulfide ketone resin obtained in Example 2.

Detailed ways

The invention discloses a resource-recyclable high-purity polyarylether and a preparation method thereof. The invention is characterized in that sulfide and dichloro aromatic compound are used as raw materials, and the resin is purified and the solvent is recovered through a solution polycondensation reaction and a subsequent extraction process, and an organic solvent is leached to recover the auxiliary agent; ultrapure polyarylether (purity ≥ 99.99%) is obtained, the whiteness of the obtained polyarylether resin is ≥ 85, and the impurity content (including volatile matter and ash) is ≤ 12ppm; and the entire preparation process realizes the complete recycling of solvents, auxiliary agents and by-product salts, which is green, environmentally friendly, and reduces costs and improves efficiency.

The resource-recyclable high-purity polyarylether of the present invention can be prepared by the following specific implementation methods:

0.1-500 parts of auxiliary agent, 400-6000 parts of solvent and 56-360 parts of sulfide are added into a reaction kettle, and dehydrated at 140-230°C for 0.5-3h under nitrogen protection to obtain a dehydrated reaction solution. When the temperature of the solution drops to 80-180°C, 114-600 parts of dichloro aromatic compound are added, and the reaction is carried out at 150-230°C for 0.5-8h, and then the temperature is maintained at 230-280°C for 0.5-10h, and the temperature is lowered to 150-220°C, and high-temperature filtration is performed to recover part of the solvent in the reaction slurry. , and transported to the solvent recovery tank; the filtered material is cooled to 10-160°C and transported to the extraction kettle, and the extractant is added in batches under closed conditions at a temperature of 10-160°C and a pressure of 0-1MPa to extract the remaining solvent 1-5 times; the mixed solution after extraction is filtered and sent to the rich extractant mixed liquid tank, and it is mixed with 1-3 parts of the solvent-containing mixed liquid in step 1) according to a volume ratio of 1-5 parts: centrifugal extraction or countercurrent tower extraction, and the mixed solution containing solvent and extractant is sent to the solvent/extractant tank, and the water is sent to the washing water tank; and the mixed solution containing solvent and extractant is subjected to Distillation separation, respectively recover the extractant and solvent for recycling; the crude solid resin product after filtration and extraction (mainly salt and auxiliary agent, almost no solvent) uses 300-3000 parts of auxiliary agent leaching agent for auxiliary agent recovery and separation, the liquid after leaching is subjected to multi-effect evaporation, the liquid is recovered and used as the auxiliary agent leaching agent for the next batch of materials, and the solid is the recovered auxiliary agent, which can be used directly without post-treatment; the crude solid resin product after leaching is washed with 300-1000 parts of desalted water or washing water from the previous batch of products for 3-5 times, each time for countercurrent washing and solid-liquid separation to remove the product The separated water-containing polyarylether resin is dried at a temperature of 80 to 120°C and a vacuum degree of 0.03 to 0.095 MPa for 1 to 12 hours to obtain a purified polyarylether resin, the obtained resin having a whiteness of ≥85 and an impurity content (including volatile matter and ash) of ≤12ppm; and the washing water is sent to the washing water tank and the extracted water separated in step 3) and oxidized at room temperature to 60°C under the action of an oxidant to remove organic matter and ammonia nitrogen impurities in the washing water, and is efficiently converted in the electrolytic cell and under the action of an electrolytic catalyst to generate sodium hydroxide, chlorine and hydrogen.

The existing patent applications or patents for polyarylether resins and methods for preparing the same have defects such as low whiteness, low purity, high impurity content, low solvent recovery rate, or difficulty in distinguishing between the recovery of additives and solvents. For example, in the invention with application number 2013104328307 and invention name of a polyarylether sulfide and method for preparing the same, the whiteness of the obtained polyarylether sulfide resin is only 60-70, and the impurity content (including volatile matter and ash) is 200-2000ppm; in the invention with application number 2013106908646 and invention name of a high-purity autocatalytic polyarylether sulfide and method for preparing the same, the solvent recovery rate is only 94% at most, the whiteness of the obtained polyarylether sulfide resin is 70, and the impurity content (including volatile matter and ash) is 150ppm; in the invention with application number 2016103482486 and invention name of an environmentally friendly and economical polyarylether and method for preparing the same, the whiteness of the obtained polyarylether resin is only 60-70, and the impurity content (including volatile matter and ash) is 200-2000ppm. During the preparation process, the washing water after the solvent enrichment must be further recovered by the extraction-distillation method, and the whiteness of the obtained polyarylene sulfide resin is only 55-70, and the impurity content is 200-300ppm; in the invention with application number "2016105274115, invention name is a high-whiteness polyarylene sulfide with narrow particle size distribution and preparation method thereof", the impurity content of the obtained polyarylene sulfide resin is 200-400ppm, and the maximum solvent recovery rate is 85-90%; and the above-mentioned disclosed applications have not achieved the separation of the recovery of auxiliary agents and solvents in the preparation process of polyarylene ether resins and achieved high auxiliary agent recovery rate and recovered auxiliary agent purity, solvent recovery rate and recovered solvent purity.

The present invention simultaneously introduces extraction and catalytic electrolysis technologies into the preparation process of polyarylether resin for the first time, and adopts the process of "recovering part of the solvent by high-temperature filtration - extracting and recovering the remaining solvent - recovering the auxiliary agent to purify the resin - catalytic electrolysis and recycling of by-product sodium chloride", thereby obtaining high-purity (purity ≥99.99%) and high-whiteness (whiteness ≥85) high-quality polyarylether resin, and the final impurity content is extremely low (impurity content (including volatile matter, ash content) ≤12ppm); and the solvent recovery rate and auxiliary agent recovery rate are both high in the whole preparation process, and the purity of the recovered solvent, auxiliary agent and extractant is also high, and at the same time, the high-value recycling of the by-product sodium chloride is realized, which is conducive to the large-scale and high-quality development of the polyarylether industry.

The present invention is described in detail below through examples. It is necessary to point out that the examples are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Those skilled in the art in this field can make some non-essential improvements and adjustments based on the above contents of the present invention.

Example 1

50kg sodium hydroxide, 60kg lithium acetate, 800kg 1,3-dimethyl-2-imidazolidinone and 117.5kg of aqueous sodium hydrosulfide are dehydrated and reacted at a temperature of 210°C for 0.5h under nitrogen protection to obtain a dehydrated reaction solution. When the temperature of the above solution drops to 170°C, 147kg of p-dichlorobenzene is added, and the reaction is carried out at a temperature of 230°C for 1h, and then kept at a temperature of 260°C for 6h, and then cooled to 200°C, and a high-temperature filtration is performed to recover part of the solvent in the reaction slurry and transport it to a solvent recovery tank; the filtered material is cooled to 160°C and sent to an extraction kettle, and 500kg of ethyl acetate, an extractant, is added in batches, and the remaining solvent is extracted 5 times under closed conditions at a temperature of 30°C and normal pressure; the mixed solution after extraction is filtered and sent to a rich extractant mixed liquid tank, and it is mixed with the solvent-containing mixed liquid in step 1) at a volume ratio of 5:1 for centrifugal extraction, and the mixed solution containing the solvent and the extractant is sent to the solvent/extractant tank, and the water is sent to the washing water tank; and the mixed solution containing the solvent and the extractant is sent to the solvent/extractant tank, and the water is sent to the washing water tank; The combined liquid is distilled and separated, and the extractant and solvent are recovered respectively for recycling; 100kg of the crude solid resin product containing the auxiliary agent after the above extraction and filtration and 800kg of isopropanol are added to the auxiliary agent extractor for continuous spray countercurrent transmission leaching, the speed of the extractor is 6r/min, the leaching temperature is 50°C, and the leaching time is 10min. The resin after leaching is discharged from the upper outlet of the extractor into a centrifuge for solid-liquid separation, and the liquid extractant is sent to the feed buffer tank of the multiple-effect evaporator; the liquid part after leaching overflows from the lower outlet of the extractor and is also sent to the feed buffer tank of the multiple-effect evaporator, and then sent to the multiple-effect evaporator at 90°C and a vacuum degree of 0.06MPa for evaporation, and the pure solid auxiliary agent and liquid auxiliary agent extractant are recovered respectively, and can be directly recycled without post-treatment; the crude solid resin product after leaching is countercurrently washed with 400kg of desalted water or washing water of the previous batch of products for 5 times, solid-liquid separation, to remove the salt and A very small amount of auxiliary agent, the separated water-containing polyarylether resin was dried at a temperature of 120°C and a vacuum degree of 0.06MPa for 10h to obtain a purified polyarylether resin, with a yield of 97.4%, an intrinsic viscosity [η] = 0.39 (viscosity test solvent is 1-chloronaphthalene), a solvent recovery rate of 99.6%, an auxiliary recovery rate of 99.2%, and infrared spectrum test results are shown in Figure 1. The purity of the obtained polyarylether resin is 99.99%, the whiteness is 86, and the impurity content is 12ppm; and the wash water is sent to the wash water tank and the extraction separation water and oxidized at 60°C under the action of 10kg oxidant hydrogen peroxide to remove organic matter and ammonia nitrogen impurities in the wash water, and is efficiently converted in the electrolytic cell and under the action of the electrolytic catalyst ruthenium oxide to generate sodium hydroxide, chlorine and hydrogen. Sodium hydroxide is used in the polymerization dehydration section, chlorine is used to prepare dihalogenated aromatic monomers, and hydrogen is recycled as a clean energy source.

Example 2

2kg of sodium hydroxide, 42kg of sodium laurate, 2500kg of sulfolane and N-methylpyrrolidone (1:2) and 180kg of aqueous sodium sulfide were dehydrated at 200°C for 3h under nitrogen protection to obtain a dehydrated reaction solution. When the temperature of the above solution dropped to 120°C, 252kg of 4,4'-dichlorobenzophenone was added and reacted at 210°C for 0.5h. The temperature was then maintained at 260°C for 6h, and the temperature was cooled to 215°C. A high-temperature filtration was performed to recover part of the solvent in the reaction slurry and transport it to a solvent recovery tank. The material after filtration was cooled to 1 0℃ to the extraction kettle, add 400kg of chloroform as the extractant in batches, extract the remaining solvent 4 times under closed conditions at a temperature of 20℃ and normal pressure; the mixed solution after extraction is filtered and sent to a rich extractant mixed solution tank, and mixed with the solvent-containing mixed solution in step 1) at a volume ratio of 4:3 for centrifugal extraction, and the mixed solution containing solvent and extractant is sent to the solvent/extractant tank respectively, and the water is sent to the washing tank; the mixed solution containing solvent and extractant is distilled and separated, and the extractant and solvent are recovered respectively for recycling; the crude solid resin product containing auxiliary agent 100k g, 1800kg chloroform is added into the auxiliary agent extractor for continuous spray countercurrent transmission extraction, the rotation speed of the extractor is 8r/min, the extraction temperature is 20℃, the extraction time is 10min, the resin after extraction is discharged from the upper outlet of the extractor into the centrifuge for solid-liquid separation, and the liquid extractant is sent to the feed buffer tank of the multiple-effect evaporator; the liquid part after extraction overflows from the lower outlet of the extractor and is also sent to the feed buffer tank of the multiple-effect evaporator, and then sent to the multiple-effect evaporator at 40℃ and vacuum degree of 0.06MPa for evaporation, and the pure solid auxiliary agent and liquid auxiliary extractant are recovered respectively, without After treatment, it can be directly recycled; the crude solid resin product after leaching is washed with 400 kg of desalted water or washing water from the previous batch of products for countercurrent washing and solid-liquid separation to remove the salt and a very small amount of additives contained in the product. The separated aqueous polyarylether resin is dried at a temperature of 120°C and a vacuum degree of 0.08 MPa for 10 h to obtain a purified polyarylether resin with a yield of 95.8%, an intrinsic viscosity [η] = 0.84 (the viscosity test solvent is concentrated sulfuric acid), a solvent recovery rate of 99.7%, an additive recovery rate of 99.3%, and infrared spectrum test results are shown in Figure 2. The obtained polyarylether resin has a purity of 99.99%, a whiteness of 85 and an impurity content of 11 ppm; the wash water is sent to a wash water tank to be hydrated with the extraction separation water and subjected to an oxidation treatment at 50°C under the action of 2 kg of ozone + 18 kg of hydrogen peroxide to remove organic matter and ammonia nitrogen impurities in the wash water, and is efficiently converted in an electrolytic cell and under the action of iridium oxide, an electrolytic catalyst, to generate sodium hydroxide, chlorine and hydrogen. The sodium hydroxide is used in the polymerization dehydration section, the chlorine is used to prepare dihalogenated aromatic monomers, and the hydrogen is recycled as a clean energy source.

Example 3

200 kg of potassium bicarbonate, 80 kg of sodium adipate, 2000 kg of N-cyclohexylpyrrolidone and 127 kg of aqueous sodium hydrosulfide were dehydrated at 180 ° C for 3 hours under nitrogen protection to obtain a dehydrated reaction solution. When the temperature of the above solution dropped to 160 ° C, 287 kg of 4,4'-dichlorodiphenyl sulfone was added, and the reaction was carried out at 190 ° C for 6 hours, and then kept at 230 ° C for 6 hours, cooled to 210 ° C, and filtered at high temperature to recover part of the solvent in the reaction slurry and transport it to the solvent recovery tank; the material after filtration was further cooled to 30 ° C and transported to the extraction kettle, and 400 kg of butyl acetate, an extractant, was added in batches, and extracted 4 times under closed conditions at 20 ° C and normal pressure. The residual solvent; the mixed solution after extraction is filtered and sent to the rich extractant mixed solution tank, and it is mixed with the solvent-containing mixed solution in step 1) at a volume ratio of 3:2 for centrifugal extraction, and the mixed solution containing solvent and extractant is sent to the solvent/extractant tank, and the water is sent to the washing water tank; and the mixed solution containing solvent and extractant is distilled and separated, and the extractant and solvent are recovered respectively for recycling; 100kg of the crude product of the solid resin containing the auxiliary agent after the above extraction and filtration and 1200kg of isobutyl alcohol are added to the auxiliary agent extractor for continuous spray countercurrent transmission leaching, the speed of the extractor is 16r/min, the leaching temperature is 70°C, the leaching time is 20min, and the resin after leaching is discharged from the upper outlet of the extractor into the leaching The solid-liquid separation is carried out by the centrifuge, and the liquid extractant is sent to the feed buffer tank of the multiple-effect evaporator; the liquid part after leaching overflows from the lower port of the extractor and is also sent to the feed buffer tank of the multiple-effect evaporator, and then sent to the multiple-effect evaporator for evaporation at 65°C and a vacuum degree of 0.09MPa, and the pure solid auxiliary agent and liquid auxiliary agent extractant are respectively recovered, and can be directly recycled without post-treatment; the solid resin crude product after leaching is washed with 350kg desalted water or washing water of the previous batch of products for countercurrent water washing and solid-liquid separation for 5 times, each time, to remove the salt and a very small amount of auxiliary agent contained in the product, and the separated aqueous polyarylether resin is dried at a temperature of 110°C and a vacuum degree of 0.085MPa for 6h to obtain a purified polyarylether resin, and its product The rate is 98.8%, the intrinsic viscosity [η] = 0.67 (the viscosity test solvent is N-methylpyrrolidone), the solvent recovery rate is 99.8%, the auxiliary recovery rate is 99.9%, the purity of the obtained polyarylether resin is 99.98%, the whiteness is 85, and the impurity content is 12ppm; the wash water is sent to the wash water tank and the extraction separation water and is oxidized at 50°C under the action of 2kg ozone + 35kg hydrogen peroxide to remove organic matter and ammonia nitrogen impurities in the wash water. In the electrolytic cell and under the action of iridium oxide, an efficient conversion is carried out to generate sodium hydroxide, chlorine and hydrogen. The sodium hydroxide is used in the polymerization dehydration section, the chlorine is used to prepare dihalogenated aromatic monomers, and the hydrogen is recycled as a clean energy.

Although the present invention has been described above in conjunction with the embodiments, it will be apparent to those skilled in the art that various modifications may be made to the embodiments without departing from the spirit and scope of the claims.

Claims (10)

1. A method for preparing polyarylether with high whiteness and low impurity content, characterized in that the preparation method comprises the following steps:

   1) Dehydration reaction: adding sulfide, auxiliary agent and solvent into a reaction kettle, and performing dehydration reaction under the protection of nitrogen or inert gas to obtain a dehydrated reaction solution, and sending the removed solvent-containing mixed liquid into a dehydration condensate tank for centralized treatment; after cooling the dehydrated reaction solution, reacting with a dichloro aromatic compound to obtain a reaction product mixed liquid;

   2) First solvent recovery: The reaction product mixture obtained in step 1) is filtered at high temperature at 150-220° C. to recover part of the solvent in the reaction product mixture, and the recovered solvent is transported to a solvent recovery tank and directly used for the next batch of material polymerization;

   3) Extraction method for solvent recovery and resin purification: cool the filtered material in step 2) to 10-160°C and send it to an extraction kettle, add extractant in batches, and extract the remaining solvent in batches under closed conditions at a temperature of 10-160°C and a pressure of 0-1MPa; filter the extracted mixed solution and send it to a rich extractant mixed liquid tank, and mix it with the solvent-containing mixed liquid in step 1), and then extract it by centrifugation or countercurrent tower; then send the mixed liquid containing solvent and extractant to the solvent/extractant tank, and send water to the washing water tank; and separate the mixed liquid containing solvent and extractant by distillation, and recover the extractant and solvent respectively for recycling;

   4) Reagent recovery, resin washing and washing water purification: the solid resin crude product obtained after the treatment in step 3) is subjected to the recovery and separation of the additive using an additive leaching agent; the liquid after the leaching is subjected to multi-effect evaporation, the liquid is recovered and used as the next batch of additive leaching agent, and the solid is the recovered additive, which can be used directly without post-treatment; the solid resin crude product after the leaching is subjected to countercurrent washing and solid-liquid separation using desalted water or washing water from the previous batch of products, and the separated water-containing polyarylether resin is vacuum dried to obtain polyarylether with high whiteness and low impurity content; and the washing water is sent to the washing water tank to be hydrated with the extraction separation in step 3) and then an oxidant is added for oxidation treatment to remove organic matter and ammonia nitrogen impurities in the washing water so that it meets the working condition requirements of electrolysis;

   5) Sodium chloride electrolysis: After the treatment in step 4), a qualified sodium chloride aqueous solution is obtained, which is placed in an electrolytic cell and converted into sodium hydroxide, chlorine and hydrogen under the action of an electrolytic catalyst; the sodium hydroxide is sold as caustic soda or used in the front-end polymerization reaction of polyarylether resin, the chlorine is used to produce the raw materials p-dichlorobenzene or 4,4'-dichlorodiphenyl sulfone in the production of polyarylether, and the hydrogen is recycled as a clean energy source;

   Wherein, each raw material is composed of the following components in parts by weight:
   
   
2. The method for preparing a high-whiteness and low-impurity polyarylether according to claim 1 is characterized in that the method of step 1) is: adding a sulfide, an additive and a solvent to a reactor, and dehydrating and reacting at a temperature of 140 to 230° C. for 0.5 to 3 hours under nitrogen protection to obtain a dehydrated reaction solution, and the removed solvent-containing mixed liquid is sent to a dehydration condensate tank for combined centralized treatment; when the temperature of the reaction solution drops to 80 to 180° C., adding a dichloro aromatic compound, reacting at a temperature of 150 to 230° C. for 0.5 to 8 hours, and then maintaining at a temperature of 230 to 280° C. for 0.5 to 10 hours to obtain a reaction product mixed liquid.
3. The method for preparing a high-whiteness and low-impurity polyarylether according to claim 1 or 2, characterized in that the sulfide is selected from the following compounds:

   Either Na ₂ S or NaHS;

   The structural formula of the dichloro aromatic compound is Cl-Ar-Cl, wherein:
   

   At least one of, wherein m=2, 4, 6, 8 or 10;

   Further, in step 1), the solvent is at least one of formamide, acetamide, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, N,N-dimethylpropylene urea, 1,3-dimethyl-2-imidazolidinone, N-cyclohexylpyrrolidone, hexamethylphosphoric triamide, cyclopentane, diphenyl sulfone, ε-caprolactam, dimethyl sulfoxide, dimethyl sulfone, quinoline, isoquinoline, 2,4-dimethylcyclopentane or N-methylcaprolactam; or the solvent is a high-purity solvent with a purity of ≥99% recovered in step 3) of the preparation method;

   Further, in step 1), the auxiliary agent is lithium hydroxide, sodium hydroxide, potassium hydroxide, magnesium hydroxide, Calcium, barium hydroxide, aluminum hydroxide, lithium carbonate, sodium carbonate, potassium carbonate, magnesium carbonate, calcium carbonate, barium carbonate, lithium bicarbonate, sodium bicarbonate, potassium bicarbonate, magnesium bicarbonate, calcium bicarbonate, barium bicarbonate, lithium acetate, sodium acetate, potassium acetate, lithium benzoate, sodium benzoate, lithium ethylenediaminetetraacetate, sodium ethylenediaminetetraacetate, trisodium ethylenediaminetetraacetate, potassium ethylenediaminetetraacetate, tripotassium ethylenediaminetetraacetate, sodium dodecylbenzenesulfonate, sodium p-toluene benzoate, lithium p-toluene benzoate, sodium terephthalate, sodium terephthalate, sodium p-toluenesulfonate, sodium p-aminobenzenesulfonate, sodium oxalate, At least one of lithium oxalate, sodium succinate, lithium succinate, sodium adipate, lithium adipate, lithium chloride, sodium phosphate, lithium phosphate, sodium tartrate, lithium tartrate, potassium tartrate, sodium alginate, sodium gluconate, sodium lactate, sodium sorbate, potassium sorbate, sodium lysine, potassium lysine, sodium cystine, sodium 6-aminocaproate, sodium heptanoate, sodium laurate, sodium citrate, sodium glycocholate, dioctyl sodium succinate, sodium ethylenediaminetetramethylenephosphate, sodium diethylenetriaminepenta(methylenephosphonate), sodium aminetri(methylenephosphate), dodecyltriethylammonium chloride, dodecyldimethylammonium bromide or sodium stearate.
4. The method for preparing a high-whiteness and low-impurity polyarylether according to any one of claims 1 to 3, characterized in that in step 3), the volume ratio of the mixed solution after extraction to the solvent-containing mixed solution in step 1) is: 1 to 5 parts: 1 to 3 parts.
5. The method for preparing a high-whiteness and low-impurity polyarylether according to any one of claims 1 to 4, characterized in that in step 3), the extractant is any one of chloroform, dichloromethane, tetrachloroethane, carbon tetrachloride, cyclohexane, ethyl acetate, butyl acetate or isopropyl ether.
6. The method for preparing a high-whiteness and low-impurity polyarylether according to any one of claims 1 to 5, characterized in that in step 4), the method of using an auxiliary agent leaching agent to recover and separate the auxiliary agent is as follows: 100 parts of the crude solid resin product obtained in step 3) and 300 to 3000 parts of the auxiliary agent leaching agent are added to an auxiliary agent leaching device for continuous spray countercurrent transmission leaching, the rotation speed of the leaching device is 2 to 30 r/min, the leaching temperature is 20 to 80° C., and the leaching time is 1 to 60 min; the leached resin is discharged from the upper outlet of the leaching device into a centrifuge for solid-liquid separation, and the liquid leaching agent is sent to a multiple-effect evaporator feed buffer tank; the liquid part after leaching overflows from the lower outlet of the leaching device and is also sent to the multiple-effect evaporator feed buffer tank, and then sent to the multiple-effect evaporator at 40 to 90° C. and a vacuum degree of 0.04 to 0.09 MPa for evaporation, the liquid after the multiple-effect evaporation is recovered and used directly as the next batch of auxiliary agent leaching agent, and the solid after the multiple-effect evaporation is recovered and used directly as an auxiliary agent.
7. A method for preparing a high-whiteness and low-impurity polyarylether according to any one of claims 1 to 6, characterized in that, in step 4), the solid resin crude product after leaching is washed with 300 to 1000 parts of desalted water or washing water from the previous batch of products for countercurrent washing and solid-liquid separation 3 to 5 times, each time with 300 to 1000 parts of desalted water or washing water from the previous batch of products, to remove the salt and a very small amount of additives contained in the product, and the separated aqueous polyarylether resin is dried at a temperature of 80 to 120° C. and a vacuum degree of 0.03 to 0.095 MPa for 1 to 12 hours to obtain a high-whiteness and low-impurity polyarylether resin; and the washing water is sent to the washing water tank and the extraction separation hydrate in step 3) and oxidized at room temperature to 60° C. under the action of an oxidant to remove organic matter and ammonia nitrogen impurities in the washing water to meet the electrolytic purity requirements.
8. The method for preparing a high-whiteness and low-impurity polyarylether according to any one of claims 1 to 7, characterized in that In step 4), the auxiliary leaching agent is at least one of methanol, ethanol, propanol, ethylene glycol, propylene glycol, glycerol, isopropanol, isobutanol, tert-butanol, n-butanol, n-pentanol, isopentanol, n-hexanol, n-heptanol, n-octanol, isooctyl alcohol, acetone, butanone, cyclopentanone, cyclohexanone, chloroform, dichloromethane, tetrachloroethane or carbon tetrachloride;

   Further, in step 5), the oxidant is at least one of hydrogen peroxide, ozone, Fenton's reagent or ferric chloride;

   Furthermore, in step 5), the electrolytic catalyst is at least one of ruthenium oxide, yttrium oxide, cerium oxide, lanthanum oxide, titanium dioxide or iridium oxide.
9. A polyarylene ether, characterized in that the polyarylene ether is prepared by the method described in any one of claims 1 to 8.
10. The polyarylene ether according to claim 9, characterized in that the whiteness of the polyarylene ether is ≥ 85; and/or:

    The impurity content of the polyarylether is ≤12ppm; and/or:

    The purity of the polyarylether is ≥99.9%.