Method for separating and recycling components of flame-retardant polyamide material

Abstract

The invention discloses a method for separating and recycling components of a flame-retardant polyamide material, aiming at solving the problem of environmental pollution of flame-retardant polyamide waste plastic products, improving the resource recycling efficiency, providing a new way for supplying high-quality regenerated high-value chemicals for industrial production and innovating a new normal form for resource regeneration recycling economy development. The method comprises the following steps: decomposing the molecular structure of a nylon resin matrix in the flame-retardant polyamide material in an acidolysis manner so as to separate brominated polystyrene, reinforced fibers and other added and filled components from the nylon resin matrix; high-quality recovered products such as brominated polystyrene and antimony trioxide are obtained through separation, purification and recovery technologies such as solvent extraction and precipitation, and are circularly used for producing flame-retardant materials such as flame-retardant polyamide and flame-retardant polyester, so that resource recycling of high-value chemicals such as brominated polystyrene and antimony trioxide is realized; the method has remarkable economic benefits, environmental benefits and social benefits, and has a wide application prospect.

Description

Technical Field

[0001] This invention relates to a method for separating, recycling, and reusing components of flame-retardant polyamide materials, belonging to the field of circular economy technology. Background Technology

[0002] Polyamide materials are among the fastest-growing engineering plastics in recent years, characterized by large production volumes and wide applications. They mainly include polyamide 6, polyamide 66, and polyamide 46, and can be used to produce fibers, films, and engineering plastic products. They are essential basic materials in clothing, automobiles, electronics, rail transportation, and aerospace. To address the fire risk posed by the inherent flammability of polyamide materials, current methods primarily involve adding high-value chemicals such as brominated polystyrene (BPS), antimony trioxide (Sb₂O₃), and diethylaluminum hypophosphite to modify them for flame retardancy, thus preparing flame-retardant polyamide materials that meet the fire safety performance requirements of the manufacturing sector. However, the rapid development and widespread application of polyamide materials have also generated an increasing amount of polyamide waste. If this waste is directly disposed of as garbage, it will cause significant environmental pollution and resource waste.

[0003] Developing recycling technologies for flame-retardant polyamide materials widely used in automobiles, electronics, rail transportation, and aerospace, and effectively addressing the recycling needs of flame-retardant polyamide waste, has become a key direction for supporting the high-quality and sustainable development of the polyamide industry. The recycling methods for flame-retardant polyamide materials can be mainly divided into two aspects: physical recycling methods, which involve mechanical crushing followed by melting and reprocessing, and chemical recycling methods, which involve chemical decomposition followed by component separation. The former has a simple implementation process but is difficult to control, while the latter, although technically challenging, offers better controllability. Currently, there are few reports on recycling methods that utilize the chemical decomposition and component separation of flame-retardant polyamide materials based on their composition and value characteristics (including commonly used high-value flame retardants and their synergists).

[0004] Based on this, the present invention aims to address the lack of research on recycling methods for flame-retardant polyamide materials, especially the lack of research on recycling methods for high-value flame-retardant chemicals BPS and Sb2O3 in flame-retardant polyamide materials. It develops a recycling technology for high-value components of flame-retardant polyamide materials with controllable recycling stability, provides a strategy for recycling waste flame-retardant polyamide, solves the environmental pollution problem of waste flame-retardant polyamide plastic products, improves resource recycling efficiency, provides a new way to supply high-quality recycled high-value chemicals for industrial production, and innovates a new paradigm for the development of a resource recycling and circular economy. Summary of the Invention

[0005] The purpose of this invention is to provide a method for separating and recycling components of flame-retardant polyamide materials, filling the current technological gap in the recycling of high-value components of flame-retardant polyamide materials. This method involves separating high-value chemicals such as BPS and Sb2O3, which have excellent recycling stability, based on the chemical decomposition of the polyamide material matrix, thereby improving the resource recycling efficiency of high-performance flame-retardant polyamide materials with excellent electrical properties.

[0006] The technical solution adopted in this invention is as follows: A method for separating, recycling, and reusing components of a flame-retardant polyamide material includes: Step (1): Under normal pressure and stirring conditions, add flame-retardant polyamide material or its acid hydrolysis synergist to an acidic aqueous solution, stir and react at 60~120℃ for 2~12 hours, cool to 20~40℃, and filter to separate solid product A and liquid product A. Step (2): After washing solid product A with water until neutral, add it to a haloalkane and stir to dissolve at 10~80℃ for 0.5~2 hours. Then filter to separate solid product B and liquid product B. After desolventizing and drying the separated solid product B, regenerated reinforcing fiber is obtained. The separated liquid product B is added dropwise to water at 85~100℃ for flash evaporation and desolventization. After filtration and drying, regenerated brominated polystyrene (Re-BPS) is obtained. Step (3): After adjusting the pH of the liquid product A to 7-9 using an alkaline solution, continue stirring the reaction for 0.1-2 hours, filter and separate the precipitated solid product C; add the separated solid product C to trifluoroethanol, stir at 20-80℃ for 0.5-4 hours, filter and dry the solid product D to obtain regenerated antimony trioxide (Re-Sb2O3).

[0007] In the above technical solution, the flame-retardant polyamide material is composed of the following raw materials: polyamide (40-95 parts by weight), reinforcing fiber (0-50 parts by weight), BPS (5-30 parts by weight), Sb2O3 (0-18 parts by weight), and other additives and fillers (0-20 parts by weight); wherein: The polyamide is one or more of aliphatic polyamide, aromatic polyamide and semi-aromatic polyamide, and may specifically include polyamide 6, polyamide 66, polyamide 46 and polyamide 10T, etc.

[0008] The reinforcing fiber is one or a mixture of glass fiber and carbon fiber, i.e., the mass ratio of glass fiber to carbon fiber is 0:1 to 1:0.

[0009] The BPS has a bromine content of 50% to 70% (mass fraction) and a weight-average molecular weight of 3,000 to 300,000 Da.

[0010] The other additives and fillers mentioned are one or more of the following: flame retardant synergists, antioxidants, colorants, antistatic agents, light stabilizers, heat stabilizers, lubricants, release agents, processing modifiers, etc.

[0011] In this invention, the decomposition of the polyamide matrix is ​​achieved through step (1) (referred to as "polyamide acid hydrolysis").

[0012] Preferably, the acid hydrolysis synergist in step (1) is one or more of the following metal halides: zinc chloride, zinc bromide, calcium chloride, calcium bromide, sodium chloride, sodium bromide, potassium chloride, potassium bromide, etc., and hydrated metal halides such as aluminum chloride hexahydrate; the amount of the acid hydrolysis synergist is 0~100g / 1kg of flame-retardant polyamide material.

[0013] The presence of the acid hydrolysis synergist can accelerate the disintegration and decomposition of the polyamide matrix in the above-mentioned "polyamide acid hydrolysis" step by promoting stress cracking of the polyamide matrix; when the acid hydrolysis synergist is absent, the polyamide matrix can also be fully decomposed in the above-mentioned "polyamide acid hydrolysis" step by extending the treatment time and / or increasing the treatment temperature.

[0014] Preferably, the acidic aqueous solution in step (1) is an acidic aqueous solution containing one or more combinations of inorganic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, sulfurous acid, phosphoric acid, phosphorous acid, hypophosphoric acid, and nitric acid; the mass fraction of inorganic acid in the acidic aqueous solution is 5% to 98%; and the amount of the acidic aqueous solution used is 1.5 to 10 L / 1 kg of flame-retardant polyamide material.

[0015] Since glass fiber, carbon fiber and BPS have good stability and insolubility in the acidic solution in step (1), after step (1) is completed, glass fiber, carbon fiber and BPS exist in solid form in solid product A.

[0016] In this invention, BPS recycling is achieved through step (2).

[0017] Since BPS is soluble in halogenated hydrocarbons, while glass fiber and carbon fiber are insoluble in halogenated hydrocarbons, the solid product A (a mixture of BPS and reinforcing fiber) is washed with water until neutral, then added to the halogenated hydrocarbons and stirred until the BPS is completely dissolved. The solid product (reinforcing fiber) and the liquid product (halogenated hydrocarbon solution of BPS) are then separated by filtration. The separated solid product (reinforcing fiber) is desolventized and dried to obtain regenerated reinforcing fiber. The separated liquid product (halogenated hydrocarbon solution of BPS) is desolventized and dried to obtain Re-BPS. The obtained Re-BPS can replace similar BPS products on the market and be recycled for the production of flame-retardant polyamides and flame-retardant polyesters. The product quality of Re-BPS can be analyzed by testing key indicators such as bromine content, weight-average molecular weight, glass transition temperature, and thermogravimetric temperature, guiding and standardizing the application of Re-BPS to replace similar products on the market.

[0018] Preferably, the halogenated hydrocarbon in step (2) is one or more of halogenated alkanes and / or halogenated aromatics, specifically including: dichloromethane, trichloromethane, dichloroethane, trichloroethane, chlorobenzene, dichlorobenzene, etc., and the amount of the halogenated hydrocarbon is 0.5~5L / 1kg of flame-retardant polyamide material.

[0019] In this invention, Sb2O3 is recycled through step (3).

[0020] Since Sb2O3 dissolves in the acidic solution (taking hydrochloric acid as an example) in step (1), the pH of the liquid product A (an acidic aqueous solution containing SbCl3 and amide oligomers) obtained in step (1) is adjusted to 7-9 using an alkaline solution. SbCl3 undergoes the following reaction in the solution: [(2x)SbCl3+6M(OH) x →(x)Sb₂O₃+6MCl x +(3x)H2O] Sb₂O₃ precipitate is generated, and amide oligomers are precipitated simultaneously. The precipitated Sb₂O₃ / amide oligomer mixture is obtained by filtration. The above Sb₂O₃ / amide oligomer mixture is added to trifluoroethanol and stirred until the amide oligomers are completely dissolved. The solid product is then filtered and dried to obtain Re-Sb₂O₃. The obtained Re-Sb₂O₃ can replace commercially available Sb₂O₃ products and be recycled for the production of various bromine-based flame retardant materials involving halogen-antimony synergy and flame retardant materials such as polyvinyl chloride artificial leather. The product quality of Re-Sb₂O₃ can be analyzed by XRD, infrared spectroscopy, elemental analysis, etc., to guide and standardize the application of Re-Sb₂O₃ as a substitute for similar products on the market.

[0021] Preferably, the alkaline solution in step (3) is an alkaline aqueous solution of one or more of alkali metal hydroxides, alkali metal carbonates, alkali metal sulfites, alkali metal phosphates and ammonia, specifically including sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium sulfite, potassium sulfite, sodium phosphate, potassium phosphate and ammonia; the mass fraction of alkaline solute in the alkaline solution is 1% to 40%.

[0022] Preferably, the amount of trifluoroethanol used in step (3) is 2~12L / 1kg of flame-retardant polyamide material.

[0023] Different flame-retardant polyamide materials typically have different polyamide matrix chemical structure characteristics and / or component composition characteristics. For example, antioxidants 1010 and 168 (0.1%~1% by mass) commonly used in polyamide material processing are insoluble in acidic aqueous solutions such as hydrochloric acid, but soluble in halogenated hydrocarbons such as dichloromethane. Therefore, after the flame-retardant polyamide material containing antioxidants 1010 and 168 undergoes decomposition and separation in steps (1) and (2), the antioxidants 1010 and 168 contained therein will be mixed into Re-BPS. The data results of this invention show that a small amount of antioxidants 1010 and 168 mixed into Re-BPS will not only not have a significant impact on the cyclic application performance of Re-BPS (as shown in Table 1), but may even help to improve the thermal stability of BPS to a certain extent (as shown in Table 1). Figure 3 (As shown).

[0024] Furthermore, since the glass transition temperature of BPS products currently on the market is mainly between 140 and 200°C, during the melting and processing of polyamide materials, there is not only dispersion of the BPS melt into the continuous phase of the polyamide resin matrix in the overall area, but also movement of the polyamide melt into the interior of BPS melt droplets in local micro-regions. This means that the BPS powder particles obtained in the solid product after the "polyamide acid hydrolysis" step of the flame-retardant polyamide material may contain trace amounts of polyamide components (which can be observed in the liquid NMR 1H spectrum of Re-BPS). Since the residual polyamide components in Re-BPS are extremely small, they will not have a significant impact on the recycling performance of Re-BPS in polyamide and other materials.

[0025] Flame retardant materials have become a key basic material for the development of modern manufacturing, and the recycling of flame retardant materials is also a major requirement for the country's development of a circular economy. However, there are currently few reports on recycling technologies for high-value components of flame retardant polyamide materials. This invention proposes a method for separating and recycling components of flame retardant polyamide materials, which can achieve a recovery rate of over 95% for high-value components BPS and Sb2O3 in flame retardant polyamide materials, especially a recovery rate of over 99% for BPS; the 1% weight loss temperature of Re-BPS (T d,1%384℃, glass transition temperature (T) g 147℃, weight-average molecular weight (M w 4512 Da, whiteness 46.5%, bromine content 66.58 wt%, compared with the corresponding index of the initial BPS (T d,1% 380℃, T g 148℃, M w The Re-BPS / Sb2O3 and Sb2O3 have basically the same properties (4950 Da, whiteness 43.5%, bromine content 66.60 wt%); the XRD spectra of Re-Sb2O3 and Sb2O3 are basically the same; the performance evaluation results of its application in 30% glass fiber reinforced polyamide 6 (PA6 / GF) show that the flame retardant and mechanical properties of Re-BPS / PA6 / GF are also basically consistent with the corresponding indicators of the initial BPS / PA6 / GF; in summary, the method for separating and recycling flame retardant polyamide material components proposed in this invention yields Re-BPS and Re-Sb2O3 with excellent recycling stability, which can replace similar products on the market and be recycled for the production of flame retardant polyamides and flame retardant polyesters, etc., with significant economic, environmental and social benefits and broad application prospects. Attached Figure Description

[0026] Figure 1 Infrared spectra of BPS and Re-BPS; Figure 2 Liquid NMR 1H spectra of BPS and Re-BPS; Figure 3 Thermogravimetric curves of BPS and Re-BPS; Figure 4 Differential scanning calorimetry curves of BPS and Re-BPS; Figure 5. Molecular weight distribution curves of BPS and Re-BPS; Figure 6 Infrared and XRD spectra of Sb2O3 and Re-Sb2O3. Detailed Implementation

[0027] The present invention is further illustrated below with reference to the embodiments; these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention; experimental methods in the following embodiments that do not specify specific conditions are generally performed according to conventional conditions in the art; the raw materials and reagents used, unless otherwise specified, are all raw materials and reagents that can be obtained from conventional markets and other commercial channels; unless otherwise specified, the amount of raw materials refers to mass, and the proportion of raw materials refers to mass fraction; any non-substantial changes and substitutions made by those skilled in the art based on the present invention are within the scope of protection claimed by the present invention.

[0028] Examples 1-5 relate to a method for preparing flame-retardant polyamide materials, comprising the following steps: PA6 (42.84%), GF (30%), BPS (19%), Sb2O3 (7.86%), antioxidant 1010 (0.1%), and antioxidant 168 (0.2%) are mixed uniformly according to mass fractions, then melt-blended, extruded, granulated, and molded to obtain the flame-retardant polyamide material; the initial BPS parameter is T. d,1% 380℃, T g 148℃, M w 4950 Da, whiteness 43.5%, bromine content 66.60 wt%; when it comes to the method of separating and recycling the components of flame-retardant polyamide materials, a mechanical crusher is used to crush the flame-retardant polyamide material obtained above into granules.

[0029] Example 1 Under normal pressure and stirring conditions, flame-retardant polyamide granules (100g) were added to 15% hydrochloric acid (700ml). The system temperature was raised to 85℃ and the acid hydrolysis reaction was carried out at a constant temperature for 4 hours. The solid phase product and liquid phase product were separated by filtration. (1) The solid phase product was washed with deionized water until neutral and then added to dichloromethane (200mL). After stirring and dissolving at room temperature for 0.5 hours, the filtrate was separated by filtration. The obtained filtrate was slowly added dropwise to water at 95℃ for flash evaporation, filtration, and drying to obtain white powdered Re-BPS with a recovery rate of 96.0%. The T of Re-BPS was obtained. d,1% 384℃, T g 147℃, M w 4512Da, whiteness 46.5%, bromine content 66.58wt%; (2) The pH of the liquid phase product was adjusted to 8 using a 10% sodium hydroxide solution. After stirring for 1.5 hours, the Sb2O3 / amide oligomer mixture was separated by filtration and added to trifluoroethanol (800mL). After stirring at 40℃ for 2 hours, the amide oligomer was completely dissolved. After filtration, washing with water and drying, white powder Re-Sb2O3 was obtained with a recovery rate of 95.8%.

[0030] Example 2 Under normal pressure and stirring conditions, flame-retardant polyamide granules (150g) were added to 30% hydrochloric acid (400ml). The system temperature was raised to 70℃ and the acid hydrolysis reaction was carried out at a constant temperature for 2.5 hours. The solid phase product and liquid phase product were separated by filtration. (1) The solid phase product was washed with deionized water until neutral and then added to dichloroethane (150mL). After stirring and dissolving at 50℃ for 1 hour, the filtrate was separated by filtration. The obtained filtrate was slowly added dropwise to water at 92℃ for flash evaporation, filtration, and drying to obtain white powdered Re-BPS with a recovery rate of 98.5%. The T of Re-BPS was obtained. d,1%382℃, T g 148℃, M w 4726 Da, whiteness 44.8%, bromine content 66.50wt%; (2) The pH of the liquid phase product was adjusted to 7 using a 20% sodium hydroxide solution. After stirring for 0.5 hours, the Sb2O3 / amide oligomer mixture was separated by filtration and added to trifluoroethanol (1500mL). After stirring at 60℃ for 1.5 hours, the amide oligomer was completely dissolved. After filtration, washing with water and drying, white powder Re-Sb2O3 was obtained with a recovery rate of 96.1%.

[0031] Example 3 Under normal pressure and stirring conditions, flame-retardant polyamide granules (100g) were added to 70% sulfuric acid (500ml). The system temperature was raised to 80℃ and the acid hydrolysis reaction was carried out at a constant temperature for 5 hours. The solid phase product and liquid phase product were separated by filtration. (1) The solid phase product was washed with deionized water until neutral and then added to dichloromethane (100mL). After stirring and dissolving at 15℃ for 1.5 hours, the filtrate was separated by filtration. The obtained filtrate was slowly added dropwise to water at 98℃ for flash evaporation, filtration, and drying to obtain white powdered Re-BPS with a recovery rate of 97.2%. The T of Re-BPS was obtained. d,1% 381℃, T g 150℃, M w 4634Da, whiteness 44.2%, bromine content 66.48wt%; (2) The pH of the liquid phase product was adjusted to 9 using a 30% potassium hydroxide solution. After stirring for 1 hour, the Sb2O3 / amide oligomer mixture was separated by filtration and added to trifluoroethanol (1000mL). After stirring at 50℃ for 2 hours, the amide oligomer was completely dissolved. After filtration, washing with water and drying, white powder Re-Sb2O3 was obtained with a recovery rate of 95.6%.

[0032] Example 4 Under normal pressure and stirring conditions, flame-retardant polyamide granules (100g) and zinc chloride (2g) were added to 20% hydrochloric acid (300ml). The system temperature was raised to 85℃ and the acid hydrolysis reaction was carried out at a constant temperature for 2 hours. The solid phase product and liquid phase product were separated by filtration. (1) The solid phase product was washed with deionized water until neutral and then added to dichloromethane (150mL). After stirring and dissolving at 25℃ for 1 hour, the filtrate was separated by filtration. The obtained filtrate was slowly added dropwise to water at 88℃ for flash evaporation, filtration, and drying to obtain white powdered Re-BPS with a recovery rate of 99.2%. The T of Re-BPS was obtained. d,1% 384℃, T g 149℃, M w4598 Da, whiteness 45.8%, bromine content 66.52wt%; (2) The pH of the liquid phase product was adjusted to 8 using 8% sodium hydroxide solution. After stirring for 2 hours, the Sb2O3 / amide oligomer mixture was separated by filtration and added to trifluoroethanol (600mL). After stirring at 80℃ for 3 hours, the amide oligomer was completely dissolved. After filtration, washing with water and drying, white powder Re-Sb2O3 was obtained with a recovery rate of 96.3%.

[0033] Example 5 Flame-retardant polyamide materials were prepared by replacing the initial BPS with the Re-BPS recovered in Example 1, and the application effects of the initial BPS and Re-BPS in the flame-retardant polyamide materials were compared (Table 1).

[0034] Table 1 Comparison of the application effects of BPS and Re-BPS in flame-retardant polyamide materials In Example 1, the infrared spectrum, liquid nuclear magnetic resonance hydrogen spectrum, thermogravimetric curve, differential scanning calorimetry curve, and molecular weight distribution curve of the prepared Re-BPS and its initial BPS are as follows: Figures 1-5 As shown; the XRD curves of Re-Sb₂O₃ and its initial Sb₂O₃ prepared in Example 1 are shown below. Figure 6 As shown.

[0035] As can be seen, the method for separating and recycling flame-retardant polyamide material components proposed in this invention can not only recycle the high-value components BPS and Sb2O3 in waste flame-retardant polyamide materials, but also directly replace similar commercially available products and be recycled for use in the production of fire safety materials such as flame-retardant polyamide. This fills the gap in market demand, ensures the production needs of fire safety materials in the manufacturing industry, and creates considerable economic, environmental and social benefits.

Claims

1. A method for separating, recycling, and reusing components of a flame-retardant polyamide material, characterized in that, Including the following: Step (1): Under normal pressure and stirring conditions, add flame-retardant polyamide material or its acid hydrolysis synergist to an acidic aqueous solution, stir and react at 60~120℃ for 2~12 hours, and then filter to separate solid product A and liquid product A. Step (2): After washing solid product A with water until neutral, add it to a haloalkane and stir to dissolve at 10~80℃ for 0.5~2 hours. Then filter to separate solid product B and liquid product B. After desolventizing and drying the separated solid product B, regenerated reinforcing fiber is obtained. Add the separated liquid product B dropwise to water at 85~100℃ for flash evaporation and desolventization. After filtration and drying, regenerated brominated polystyrene Re-BPS is obtained. Step (3): After adjusting the pH of the liquid product A to 7-9 using an alkaline solution, continue stirring the reaction for 0.1-2 hours, filter and separate the precipitated solid product C; add the separated solid product C to trifluoroethanol, stir at 20-80℃ for 0.5-4 hours, filter and dry the solid product D to obtain regenerated antimony trioxide Re-Sb2O3.

2. The method for separating, recycling, and reusing components of a flame-retardant polyamide material according to claim 1, characterized in that, The flame-retardant polyamide material in step (1) is composed of the following raw materials: 40-95 parts by weight of polyamide, 0-50 parts by weight of reinforcing fiber, 5-30 parts by weight of brominated polystyrene (BPS), 0-18 parts by weight of antimony trioxide (Sb₂O₃), and 0-20 parts by weight of other additives and fillers; the polyamide is one or a mixture of aliphatic polyamide, aromatic polyamide, and semi-aromatic polyamide; the reinforcing fiber is one or a mixture of glass fiber and carbon fiber; the BPS has a bromine content of 50wt%-70wt% and a weight-average molecular weight of 3000-300000 Da; the other additives and fillers are one or a combination of flame retardant synergists, antioxidants, colorants, antistatic agents, light stabilizers, heat stabilizers, lubricants, release agents, and processing modifiers.

3. The method for separating, recycling, and reusing components of a flame-retardant polyamide material according to claim 1, characterized in that, The acid hydrolysis synergist in step (1) is a metal halide or a hydrated metal halide, which is one or more of zinc chloride, zinc bromide, calcium chloride, calcium bromide, sodium chloride, sodium bromide, potassium chloride, potassium bromide and aluminum chloride hexahydrate; the amount of the acid hydrolysis synergist is 0~100g / 1kg of flame retardant polyamide material.

4. The method for separating, recycling, and reusing components of a flame-retardant polyamide material according to claim 1, characterized in that, The acidic aqueous solution in step (1) is an aqueous solution containing an inorganic acid, wherein the inorganic acid is one or more of hydrochloric acid, hydrobromic acid, sulfuric acid, sulfurous acid, phosphoric acid, phosphorous acid, hypophosphoric acid, and nitric acid; the mass fraction of the inorganic acid in the acidic aqueous solution is 5% to 98%; and the amount of the acidic aqueous solution used is 1.5 to 10 L / 1 kg of flame-retardant polyamide material.

5. The method for separating, recycling, and reusing components of a flame-retardant polyamide material according to claim 1, characterized in that, The halogenated hydrocarbons in step (2) are one or more of halogenated alkanes and / or halogenated aromatics, specifically including one or more of dichloromethane, trichloromethane, dichloroethane, trichloroethane, chlorobenzene, and dichlorobenzene. The amount of the halogenated hydrocarbons used is 0.5~5L / 1kg of flame-retardant polyamide material.

6. The method for separating, recycling, and reusing components of a flame-retardant polyamide material according to claim 1, characterized in that, The alkaline solution in step (3) is an alkaline aqueous solution of one or more of alkali metal hydroxides, alkali metal carbonates, alkali metal sulfites, alkali metal phosphates and ammonia, specifically including sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium sulfite, potassium sulfite, sodium phosphate, potassium phosphate and ammonia; the mass fraction of alkaline solute in the alkaline solution is 1% to 40%.

7. The method for separating, recycling, and reusing components of a flame-retardant polyamide material according to claim 1, characterized in that, The amount of trifluoroethanol used in step (3) is 2~12L / 1kg of flame-retardant polyamide material.

8. The method for separating, recycling, and reusing components of a flame-retardant polyamide material according to claim 1, characterized in that, The Re-BPS in step (2) and the Re-Sb2O3 in step (3) can be recycled for the production of flame-retardant polyamide or flame-retardant polyester materials.

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