Degradation method and recycling process of waste PIR material

Abstract

According to the degradation method, an alcohol-amine compound degradation agent and a lanthanum-cobalt-nickel efficient degradation catalyst are used as degradation agents to degrade the waste PIR material. The method comprises the following steps: putting a crushed waste PIR material into a container, adding an alcohol-amine compound degradation agent and a lanthanum-cobalt-nickel efficient degradation catalyst into the container, heating to 150-200 DEG C, and stirring to obtain a PIR degradation product. The recycling process comprises the following steps: firstly, degrading the waste PIR material by using the alcohol-amine compound degradation agent and the lanthanum-cobalt-nickel efficient degradation catalyst as degradation agents to obtain a PIR degradation product. And adding hollow glass beads, a foaming expanding agent, a foaming stabilizer and a catalyst into the PIR degradation product, stirring, and foaming to obtain a regenerated PIR product. According to the degradation method disclosed by the invention, the degradation time of the waste PIR material is shortened, the degradation is relatively thorough, and the regeneration foaming speed in the regenerated PIR product prepared from the PIR degradation product obtained by the degradation method in the recycling process is controllable.

Description

Technical Field

[0001] The present invention relates to the technical field of degradation and recycling of waste PIR materials, and specifically relates to a degradation method and recycling process of waste PIR materials. Background Art

[0003] In the prior art, there are technologies for degrading PIR materials by using alcohol series degradants, amine series degradants, alkali metal catalysts, etc. alone. However, since the PIR molecule has a cross-linked network structure and its urea bond energy is relatively large, when using alcohol series degradants and amine series degradants alone to degrade PIR materials at a suitable reaction temperature, their polarity is weak and the reaction activity is low, and they cannot break the urea bonds in the PIR molecular chain well. If the temperature during the degradation reaction is increased to 220 °C, although it is beneficial to the degradation of PIR materials to a certain extent, it will also produce adverse side reactions. When using alkali metal catalysts such as potassium hydroxide, sodium hydroxide, and cesium hydroxide to degrade PIR materials, the degradation reaction time is long, and the viscosity of the degradation products is high, and the degradation reaction is not complete enough. Moreover, for some high-quality products, during the process of regenerating PIR products, it is necessary to remove impurities from the alkali metal catalyst. Otherwise, the alkali metal catalyst used in the degradation reaction will play a catalytic role during the regeneration foaming process, making the regeneration foaming reaction too fast and uncontrollable, affecting the physical and chemical properties of the regenerated product. Summary of the Invention

[0004] Compared with the problems in the prior art such as weak polarity of the degradant, low reaction activity, long degradation reaction time, incomplete degradation, and uncontrollable foaming speed during the regeneration of PIR products when degrading waste PIR materials, the present invention provides a degradation method that shortens the degradation time of waste PIR materials and is completely degraded, as well as a recycling process with controllable regeneration foaming speed during the preparation of regenerated PIR products.

[0005] To solve the above technical problems, the specific solution adopted by the present invention is a degradation method of waste PIR materials, using an alcohol-amine compound degradant and a lanthanum-cobalt-nickel high-efficiency degradation catalyst as degradants to degrade waste PIR materials.

[0006] As an optimized solution of the above degradation method of waste PIR materials, it specifically includes the following steps:

[0007] S1: Place the crushed waste PIR materials in a container;

[0008] S2: Add the alcohol-amine compound degradant and the lanthanum-cobalt-nickel high-efficiency degradation catalyst into the container, heat up to 150-200 °C and stir to obtain PIR degradation products.

[0009] As another optimization solution for the degradation method of the above-mentioned waste PIR material: the mass ratio of the alcohol-amine compound degradation agent to the waste PIR material is 0.5-1.5:1; the mass ratio of the lanthanum-cobalt-nickel high-efficiency degradation catalyst to the waste PIR material is 0.001-0.02:1.

[0010] As another optimization solution for the degradation method of the above-mentioned waste PIR material: the alcohol-amine compound degradation agent is composed of a compound of an alcohol series degradation agent and an amine series degradation agent; among them, the alcohol series degradation agent is one or more of ethylene glycol, 1,3-propanediol, diethylene glycol, 1,4-butanediol, triethylene glycol, 1,2-cyclopentanediol, 1,3-cyclopentanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,4-hexanediol, 1,8-octanediol, 1,9-nonanediol, dipropylene glycol, diethylene glycol monomethyl ether and tripropylene glycol; the amine series degradation agent is one or more of dibutylamine, diethanolamine, triethylenediamine, tetramethylethylenediamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, dimethylaminoethoxyethanol and cyclohexylamine.

[0011] As another optimization solution for the degradation method of the above-mentioned waste PIR material: the mass ratio of the alcohol series degradation agent to the amine series degradation agent in the alcohol-amine compound degradation agent is 1-9:9-1.

[0012] As another optimization solution for the degradation method of the above-mentioned waste PIR material: the lanthanum-cobalt-nickel high-efficiency degradation catalyst is one or more of La-Co bimetallic catalyst, La-Ni bimetallic catalyst, Co-Ni bimetallic catalyst and La-Co-Ni trimetallic catalyst.

[0013] As another optimization solution for the degradation method of the above-mentioned waste PIR material: the lanthanum-cobalt-nickel high-efficiency degradation catalyst is LaCoO3, LaNiO3, LaCo 0.2 Ni 0.8 O3, LaCo 0.4 Ni 0.6 O3, LaCo 0.6 Ni 0.4 O3 and LaCo 0.8 Ni 0.2 O3 or one or more of them.

[0014] A recycling process for waste PIR materials specifically includes the following steps:

[0015] S1: Place the crushed waste PIR material in a container, then add the alcohol-amine compound degradation agent and the lanthanum-cobalt-nickel high-efficiency degradation catalyst into the container, heat up to 150-200 °C and stir to obtain the PIR degradation product;

[0016] S2: Add hollow glass microspheres, foaming expandant, foaming stabilizer, and catalyst into the PIR degradation product obtained in the above step S1, and stir.

[0017] S3: Pour the product in step S2 into a foaming mold for foaming treatment to obtain regenerated foam; place the regenerated foam in an oven for curing treatment to obtain a regenerated PIR product.

[0018] As an optimized solution for the above recycling process of waste PIR materials: the mass ratio of hollow glass microspheres to waste PIR materials is 0.01 - 0.2:1; the mass ratio of foaming expandant to waste PIR materials is 0.02 - 0.2:1; the mass ratio of foaming stabilizer to waste PIR materials is 0.01 - 0.1:1; the mass ratio of catalyst to waste PIR materials is 0.01 - 0.1:1.

[0019] As another optimized solution for the above recycling process of waste PIR materials: the mesh number of hollow glass microspheres is 30 - 100, and its diameter is 3 - 200 μm.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention uses an alcohol-amine compound degradation agent composed of an alcohol series degradation agent and an amine series degradation agent as a co-reactant. Under the synergistic effect, the electrophilicity of the isocyanurate functional group is increased, promoting the attachment of the compound degradation agent to the isocyanurate functional group and improving the reaction rate of the compound degradation agent with polyisocyanurate. The adsorbed oxygen on the surface of the lanthanum-cobalt-nickel high-efficiency metal catalyst in the present invention tends to adsorb and capture the electrons of La, Co, and Ni ions. Therefore, the existence of adsorbed oxygen can not only help generate strongly oxidizing hydroxyl radicals, but also promote the transformation of La ions, Co ions, and Ni ions, making the La-O, Ni-O, and Co-O bonds more exposed on the catalyst surface, generating more oxygen vacancies, having higher migration ability and better catalytic activity during the oxidation reaction, and being able to significantly improve the degradation effect of the catalyst. When the oxygen vacancy content of the prepared catalyst is 60% - 80%, the effect of degrading PIR is the best. Moreover, the usage amount of the lanthanum-cobalt-nickel high-efficiency metal catalyst is only 5 - 20% of the usage amount of the alkali metal catalyst. During the regeneration process, there is no need to remove impurities from the lanthanum-cobalt-nickel high-efficiency metal catalyst. Its degradation reaction time is shorter, the viscosity of the degradation reaction product is lower, and the degradation reaction occurs more completely. The lanthanum-cobalt-nickel high-efficiency metal catalyst is combined with the degradation of PIR materials, which can more effectively break the urea bond in the PIR molecular chain, efficiently degrade the PIR materials. The reaction rate of the entire degradation process and regeneration process can be controlled, and there is no need to remove impurities from the lanthanum-cobalt-nickel high-efficiency metal catalyst during the entire degradation and regeneration process.

[0022] 2. In the present invention, hollow glass microspheres added during the foaming treatment of the degraded PIR material can further reduce the thermal conductivity of the recycled foamed PIR product and increase the compressive strength, enabling the physical and chemical property parameters such as the thermal conductivity, compressive strength, apparent density, and water absorption rate of the recycled PIR product to meet the requirements of national standards. Furthermore, the recycled PIR product can be reused as a cold insulation material for the cold insulation construction of equipment and pipelines again, saving the enterprise the cost of purchasing cold insulation materials.

[0023] 3. The degradation, recycling, and foaming regeneration process of the present invention is environmentally friendly, without the emission of three wastes, and will not cause secondary pollution to the environment, avoiding the waste of resources and environmental pollution caused by the traditional methods of incinerating and landfilling waste PIR materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic infrared spectra of different degradation products in Examples 1 - 3 and Comparative Example 1;

[0025] Figure 2 Scanning electron micrograph of the foamed recycled PIR product from the PIR degradation product in Example 1;

[0026] Figure 3 Scanning electron micrograph of the foamed recycled PIR product from the PIR degradation product in Example 2;

[0027] Figure 4 Scanning electron micrograph of the foamed recycled PIR product from the PIR degradation product in Example 3;

[0028] Figure 5 Scanning electron micrograph of the foamed recycled PIR product from the PIR degradation product in Comparative Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0029] A method for degrading waste PIR materials uses an alcohol - amine compound degradation agent and a lanthanum - cobalt - nickel highly efficient degradation catalyst as degradation agents to degrade waste PIR materials.

[0030] Specifically, it includes the following steps:

[0031] S1: Place the crushed waste PIR materials in a container;

[0032] S2: Add the alcohol - amine compound degradation agent and the lanthanum - cobalt - nickel highly efficient degradation catalyst into the container, heat up to 150 - 200 °C and stir to obtain the PIR degradation product.

[0033] In the above step S2, the mass ratio of the alcohol - amine compound degradation agent to the waste PIR materials is 0.5 - 1.5:1; the mass ratio of the lanthanum - cobalt - nickel highly efficient degradation catalyst to the waste PIR materials is 0.001 - 0.02:1.

[0034] The above-mentioned alcohol-amine compound degradation agent is composed of a compound of an alcohol series degradation agent and an amine series degradation agent; among them, the alcohol series degradation agent is one or more of ethylene glycol, 1,3-propanediol, diethylene glycol, 1,4-butanediol, triethylene glycol, 1,2-cyclopentanediol, 1,3-cyclopentanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,4-hexanediol, 1,8-octanediol, 1,9-nonanediol, dipropylene glycol, diethylene glycol monobutyl ether, and tripropylene glycol; the amine series degradation agent is one or more of dibutylamine, diethanolamine, triethylenediamine, tetramethylethylenediamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, dimethylaminoethoxyethanol, and cyclohexylamine.

[0035] In the above-mentioned alcohol-amine compound degradation agent, the mass ratio of the alcohol series degradation agent to the amine series degradation agent is 1-9:9-1.

[0036] The above-mentioned alcohol-amine compound degradation agent composed of an alcohol series degradation agent and an amine series degradation agent is used as a co-reactant. Under the synergistic effect, it can increase the electrophilicity of the isocyanurate functional group, promote the attachment of the compound degradation agent to the isocyanurate functional group, and improve the reaction rate of the compound degradation agent with polyisocyanurate. It avoids the problem that when the alcohol series degradation agent or the amine series degradation agent is used alone at a suitable degradation reaction temperature, it cannot break the urea bond in the PIR molecular chain well and needs to increase the degradation reaction temperature to cause adverse side reactions.

[0037] The above-mentioned lanthanum-cobalt-nickel high-efficiency degradation catalyst is one or more of La-Co bimetallic catalyst, La-Ni bimetallic catalyst, Co-Ni bimetallic catalyst, and La-Co-Ni trimetallic catalyst.

[0038] The above-mentioned lanthanum-cobalt-nickel high-efficiency degradation catalyst is LaCoO3, LaNiO3, LaCo 0.2 Ni 0.8 O3, LaCo 0.4 Ni 0.6 O3, LaCo 0.6 Ni 0.4 O3 and LaCo 0.8 Ni 0.2 O3, or one or more of LaCo

[0039] The adsorbed oxygen on the surface of the high-efficiency metal catalyst prepared from lanthanum, cobalt, and nickel tends to adsorb and capture the electrons of La, Co, and Ni ions. Therefore, the presence of adsorbed oxygen can not only help generate strongly oxidizing hydroxyl radicals but also promote the transformation of La ions, Co ions, and Ni ions, making more La-O, Ni-O, and Co-O bonds exposed on the catalyst surface, generating more oxygen vacancies, having higher migration ability and better catalytic activity during the oxidation reaction, and being able to significantly improve the degradation effect of the catalyst. When the oxygen vacancy content of the prepared catalyst is 60% - 80%, the effect of degrading PIR materials is the best.

[0040] The above container is a three-neck reaction kettle, which is equipped with a temperature measuring and adjusting device for detecting and controlling the reaction temperature, a stirrer for stirring the reactants to make the reactants fully contact and react completely, and a condensing and reflux device for condensing and recovering the alcohol-amine degrading agent volatilized due to heating.

[0041] In the above step S2, after the alcohol-amine degrading agent, the lanthanum-cobalt-nickel high-efficiency degrading catalyst, and the waste PIR material placed in the three-neck reaction kettle are stirred, they are first reacted at a temperature of 150 - 180 °C for 0.5 - 2 h, and then the temperature is adjusted to 180 - 200 °C and reacted for 0.5 - 2 h to obtain the PIR degradation product.

[0042] The hydroxyl value, viscosity, and infrared spectrum of the PIR degradation product obtained in the above step S2 are tested by a testing device. If the hydroxyl value range of the tested PIR degradation product is 400 - 600 mgKOH / g, the viscosity range is 1200 - 1400 mPa·s, and the characteristic peaks in the infrared spectrum are similar to those of the existing conventional PIR production foaming precursor, then regenerative foaming can be carried out.

[0043] A recycling process for waste PIR materials specifically includes the following steps:

[0044] S1: Place the crushed waste PIR material in a container, then add the alcohol-amine compound degrading agent and the lanthanum-cobalt-nickel high-efficiency degrading catalyst into the container, heat up to 150 - 200 °C and stir to obtain the PIR degradation product.

[0045] S2: Add hollow glass microspheres, foaming expandants, foaming stabilizers, and catalysts to the PIR degradation product prepared in the above step S1 and stir.

[0046] S3: Pour the product in step S2 into a foaming mold for foaming treatment to obtain regenerated foam; place the regenerated foam in an oven for curing treatment to obtain the regenerated PIR product.

[0047] In the above step S1, the mass ratio of hollow glass microspheres to waste PIR material is 0.01 - 0.2:1; the mass ratio of foaming blowing agent to waste PIR material is 0.02 - 0.2:1; the mass ratio of foaming stabilizer to waste PIR material is 0.01 - 0.1:1; the mass ratio of catalyst to waste PIR material is 0.01 - 0.1:1.

[0048] In the above step S1, the mesh number of the hollow glass microspheres is 30 - 100, and its diameter is 3 - 200 μm.

[0049] Adding hollow glass microspheres in the above step S1 can further reduce the thermal conductivity of the foamed recycled PIR product and can increase the compressive strength of the recycled PIR product as a skeleton.

[0050] In the above step S1, the foaming blowing agent is one or more of water, liquid CO2, 1,1-dichloro-1-fluoroethane, 1,1,1-trichloro-2,2,2-trifluoroethane, chlorodifluoromethane, trichlorofluoromethane, cyclopentane, n-pentane, isopentane, HFC-245fa (1,1,1,3,3-pentafluoropropane), HFC-365mfc (1,1,1,3,3-pentafluorobutane), n-butane, and dimethyl ether.

[0051] In the above step S1, the foaming stabilizer is one or more of silicone oil L-580, silicone oil SC-154, silicone oil B-8525, silicone oil DC-193, silicone oil SD-601, C12 tertiary amine, dimethyl siloxane, and polydimethyl siloxane.

[0052] In the above step S1, the catalyst is one or several of triethylenediamine, dimethylaminoethyl ether, 1,2-dimethylimidazole, tetramethylethylenediamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, dimethylaminoethoxyethanol, cyclohexylamine, sodium hydroxide, and potassium hydroxide.

[0053] Test the thermal conductivity, water absorption rate, compressive strength, apparent density, and scanning electron microscope of the recycled PIR product obtained in the above step S2 through a testing device. If the thermal conductivity (25 °C) of the tested recycled PIR product ≤ 0.029 W / (m·°C), the water absorption rate ≤ 4%, the compressive strength ≥ 0.22 MPa, and the apparent density range is 30 - 60 kg / m 3 , and the bubble holes in the scanning electron microscope are large, uniform and full, and there is no breakage, it is a qualified recycled PIR product.

[0054] Example 1

[0055] First, weigh 100 g of waste PIR material. After removing impurities, crushing, and grinding it into powder, place it in a 1000 ml three-necked reaction kettle. Then, weigh 100 g of the alcohol-amine compound degradation agent and add it to the three-necked reaction kettle. Among them, the mass ratio of ethylene glycol, diethylene glycol, and diethanolamine in the alcohol-amine compound degradation agent is 45:45:10. Then, weigh 0.2 g of LaNiO3 catalyst and add it to the three-necked reaction kettle. Place the three-necked reaction kettle in a heating jacket and stir. Keep the temperature in the three-necked reaction kettle at 180 °C and react for 1 h. Then, adjust the temperature in the three-necked reaction kettle to 190 °C and react for 1 h. The viscous liquid obtained is the PIR degradation product. After the temperature of the PIR degradation product drops to room temperature, take it out and test its hydroxyl value, viscosity, and infrared spectrum.

[0056] Example 2

[0057] First, weigh 100 g of waste PIR material. After removing impurities, crushing, and grinding it into powder, place it in a 1000 ml three-necked reaction kettle. Then, weigh 100 g of the alcohol-amine compound degradation agent and add it to the three-necked reaction kettle. Among them, the mass ratio of tripropylene glycol, 1,4-butanediol, and N,N-dimethylethanolamine in the alcohol-amine compound degradation agent is 40:45:15. Then, weigh 0.02 g of LaCoO3 catalyst and add it to the three-necked reaction kettle. Place the three-necked reaction kettle in a heating jacket and stir. Keep the temperature in the three-necked reaction kettle at 180 °C and react for 1 h. Then, adjust the temperature in the three-necked reaction kettle to 190 °C and react for 1 h. The viscous liquid obtained is the PIR degradation product. After the temperature of the PIR degradation product drops to room temperature, take it out and test its hydroxyl value, viscosity, and infrared spectrum.

[0058] Example 3

[0059] First, weigh 100 g of waste PIR material. After removing impurities, crushing, and grinding it into powder, place it in a 1000 ml three-necked reaction kettle. Then, weigh 100 g of the alcohol-amine compound degradation agent and add it to the three-necked reaction kettle. Among them, the mass ratio of 1,4-butanediol, diethylene glycol, and N,N-diethylethanolamine in the alcohol-amine compound degradation agent is 33:47:20. Then, weigh 0.2 g of LaCo 0.4 Ni 0.6 O3 catalyst and add it to the three-necked reaction kettle. Place the three-necked reaction kettle in a heating jacket and stir. Keep the temperature in the three-necked reaction kettle at 180 °C and react for 1 h. Then, adjust the temperature in the three-necked reaction kettle to 190 °C and react for 1 h. The viscous liquid obtained is the PIR degradation product. After the temperature of the PIR degradation product drops to room temperature, take it out and test its hydroxyl value, viscosity, and infrared spectrum.

[0060] Comparative Example 1

[0061] Weigh isocyanate and polyether, and mix them in proportion to obtain a foaming precursor. Then, test the hydroxyl value, viscosity, and infrared spectrum of the foaming precursor.

[0062] The hydroxyl value and viscosity data values measured for the PIR degradation products in Examples 1 - 3 and the foaming precursor in Comparative Example 1 are summarized and compared in the following table: Hydroxyl value (mg KOH / g) Viscosity (mPa·s) Example 1 505 1325 Example 2 502 1263 Example 3 515 1230 Comparative Example 1 495 1340

[0063] As can be seen from the above table, the hydroxyl value and viscosity values of the PIR degradation products in Examples 1 - 3 are close to those of the foaming precursor in Comparative Example 1, proving that the PIR degradation products in Examples 1 - 3 have the best performance. The viscosity value is around 1300 mPa·s, indicating that the PIR degradation product has good fluidity and the degradation reaction occurs completely. The hydroxyl value is about 500 mg KOH / g, indicating that the PIR degradation product has the conditions for foaming and curing.

[0064] Secondly, as Figure 1 shown, the characteristic peaks of the infrared spectra of the PIR degradation products in Examples 1 - 3 are highly similar to those of the infrared spectra of the foaming precursor in Comparative Example 1. They show a hydroxyl stretching vibration peak at 3350 cm -1 −1, a methyl stretching vibration peak near 2900 cm -1 −1, a carbonyl characteristic absorption peak at 1737 cm -1 −1, and an ether bond characteristic absorption peak in the range close to 1050 cm -1 −1, proving that the structure of the PIR degradation products in Examples 1 - 3 is similar to that of the traditional PIR foaming precursor. Therefore, combining the hydroxyl value, viscosity, and infrared spectra of the PIR degradation products in Examples 1 - 3 above, it can be judged that the PIR degradation products in Examples 1 - 3 can be used to prepare recycled PIR products.

[0065] In the PIR degradation products of Example 1, Example 2, and Example 3 and the foaming precursor of Comparative Example 1, 5 g of hollow glass microspheres, 10 g of foaming expander n-butane, 2 g of foaming stabilizer dimethyl silicone, and 1.5 g of catalyst tetramethylethylenediamine are respectively added. After stirring evenly, they are poured into a foaming mold for foaming treatment to obtain recycled foam. Then the recycled foam is placed in an oven for curing treatment to obtain recycled PIR products. The apparent density, compressive strength, water absorption rate, and thermal conductivity of the obtained recycled PIR products are tested, and the skeleton and cell structure of the recycled PIR products are observed with a scanning electron microscope.

[0066] The values of the apparent density, compressive strength, water absorption rate, and thermal conductivity of the recycled PIR products obtained by testing Examples 1 - 3 and Comparative Example 1 are summarized in the following table; <![CDATA[Apparent density (kg / m 3 )]]> Compressive strength (MPa) Water absorption rate (%) Thermal conductivity (W / m·K) Example 1 42.01 0.431 0.0274 0.0245 Example 2 42.17 0.433 0.0266 0.0240 Example 3 45.02 0.462 0.0267 0.0243 Comparative Example 1 41.19 0.413 0.0267 0.0251

[0067] By comparing the data in the above table, it can be seen that when the foamed recycled PIR products in Examples 1-3 and the foamed recycled PIR product in Comparative Example 1 have low apparent densities at the same time, their recycled PIR products all have high compressive strengths, and their thermal conductivity, water absorption, compression strength, and apparent density all meet the national standard requirements.

[0068] From the scanning electron microscope pictures of the recycled foamed PIR products in the three groups of examples and the recycled foamed PIR products in the comparative examples Figures 2 - 5 it can be seen that the cell pores of the recycled foamed PIR products in the three groups of examples and the recycled foamed PIR products in the comparative examples are large, uniform and full, and there is no crushing phenomenon, meeting the requirements. In summary, the recycled PIR products obtained by foaming the PIR degradation products obtained in Examples 1-3 have good comprehensive properties.

Claims

1. A degradation method for waste PIR materials, characterized in that: Using an alcohol-amine compound degradation agent and a lanthanum-cobalt-nickel highly efficient degradation catalyst as degradation agents to degrade waste PIR materials.

2. The degradation method of waste PIR material according to claim 1, characterized in that: Specifically, it includes the following steps: S1: Place the crushed waste PIR materials in a container. S2: Add the alcohol-amine compound degradation agent and the lanthanum-cobalt-nickel highly efficient degradation catalyst into the container, heat up to 150 - 200 °C and stir to obtain PIR degradation products.

3. A degradation method of waste PIR material according to claim 2, characterized in that: The mass ratio of the alcohol-amine compound degradation agent to the waste PIR materials is 0.5 - 1.5:1; the mass ratio of the lanthanum-cobalt-nickel highly efficient degradation catalyst to the waste PIR materials is 0.001 - 0.02:

1.

4. A method for degrading waste PIR materials according to claim 2, characterized in that: The alcohol-amine compound degradation agent is composed of a compound of an alcohol series degradation agent and an amine series degradation agent; among them, the alcohol series degradation agent is one or more of ethylene glycol, 1,3-propanediol, diethylene glycol, 1,4-butanediol, triethylene glycol, 1,2-cyclopentanediol, 1,3-cyclopentanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,4-hexanediol, 1,8-octanediol, 1,9-nonanediol, dipropylene glycol, diethylene glycol monoethyl ether, and tripropylene glycol; the amine series degradation agent is one or more of dibutylamine, diethanolamine, triethylenediamine, tetramethylethylenediamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, dimethylaminoethoxyethanol, and cyclohexylamine.

5. A method for degrading waste PIR materials according to claim 4, characterized in that: The mass ratio of the alcohol series degradation agent to the amine series degradation agent in the alcohol-amine compound degradation agent is 1 - 9:9 - 1.

6. The degradation method of waste PIR material according to claim 2, characterized in that: The lanthanum-cobalt-nickel highly efficient degradation catalyst is one or more of La-Co bimetallic catalysts, La-Ni bimetallic catalysts, Co-Ni bimetallic catalysts, and La-Co-Ni trimetallic catalysts.

7. A method for degrading waste PIR materials according to claim 6, characterized in that: The efficient degradation catalysts of lanthanum cobalt nickel are LaCoO3, LaNiO3, LaCo 0.2 Ni 0.8 O3, LaCo 0.4 Ni 0.6 O3, LaCo 0.6 Ni 0.4 O3, and LaCo 0.8 Ni 0.2 O3, or one or more of them.

8. A recycling process for waste PIR materials, characterized in that: Specifically, it includes the following steps: S1: Place the crushed waste PIR materials in a container, then add the alcohol-amine compound degradation agent and the lanthanum-cobalt-nickel highly efficient degradation catalyst into the container, heat up to 150 - 200 °C and stir to obtain PIR degradation products. S2: Add hollow glass microspheres, a foaming agent, a foaming stabilizer, and a catalyst to the PIR degradation products obtained in the above step S1 and stir. S3: Pour the product in step S2 into a foaming mold for foaming treatment to obtain regenerated foam; place the regenerated foam in an oven for curing treatment to obtain a regenerated PIR product.

9. The recycling process of waste PIR material according to claim 8, characterized in that: The mass ratio of the hollow glass microspheres to the waste PIR materials is 0.01 - 0.2:1; the mass ratio of the foaming agent to the waste PIR materials is 0.02 - 0.2:1; the mass ratio of the foaming stabilizer to the waste PIR materials is 0.01 - 0.1:1; the mass ratio of the catalyst to the waste PIR materials is 0.01 - 0.1:

1.

10. A recycling process for waste PIR materials according to claim 8, characterized in that: The mesh number of the hollow glass microspheres is 30 - 100, and its diameter is 3 - 200 μm.

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