A method for resource utilization and application of waste plastic-based protective products

Abstract

This invention relates to the field of waste resource utilization technology, and specifically discloses a highly efficient method for the resource utilization of waste plastic-based protective equipment and its application in environmental remediation. This resource utilization method uses waste plastic-based protective equipment with high polyolefin content as a carbon source, employing a "catalytic carbonization coupled in-situ template" strategy to prepare nanoporous carbon materials in high yield under normal pressure. This invention is simple, efficient, green, and environmentally friendly, with no additional pollutant emissions. The required raw materials are recyclable, preventing resource waste. The prepared porous carbon exhibits excellent adsorption and removal performance for various phenolic drugs and emerging organic pollutants used in disinfection and sterilization in water bodies, achieving "waste-to-waste treatment."

Description

Technical Field

[0001] This invention relates to the field of waste resource utilization technology, and in particular to a method for the resource utilization of high-value nanoporous carbon materials derived from waste plastic-based protective products with high polyolefin content, and its application in the field of environmental remediation. Background Technology

[0002] Masks, protective suits, and other protective equipment are plastic-based, with polypropylene being the most abundant component. Currently, effective resource recovery methods for these types of waste plastic protective equipment are extremely limited. Traditional methods include incineration and landfill, which not only indirectly cause significant resource waste but also easily lead to secondary pollution. Furthermore, mechanical recycling, a commonly used method for recycling waste plastics, is unsuitable for processing waste medical protective products, and the resulting mixed plastics have low added value. While methods such as pyrolysis and catalytic decomposition convert waste plastics into monomers or other useful chemical raw materials, the resulting products are complex mixtures that are difficult to purify and separate.

[0003] Polypropylene, the most abundant component in plastic-based protective products, has a carbon content as high as 85.7 wt%, theoretically making it an ideal raw material for preparing high-value nano-carbon materials, such as porous carbon materials widely used as excellent adsorbents in environmental remediation. However, polyolefin materials like polypropylene tend to pyrolyze into small-molecule hydrocarbons during heating, making them difficult to carbonize and deposit into solid carbonaceous materials, thus belonging to non-carbon-forming plastics. Therefore, it is difficult to use traditional pyrolysis-activation methods to derive porous carbon materials from waste plastic-based protective products with high polyolefin content in a high yield. To address these issues, some studies have reported attempts to improve the yield of carbon materials by using concentrated sulfuric acid pretreatment or high-pressure pyrolysis. However, these methods also have significant drawbacks: the preparation process uses highly corrosive reagents, the high-pressure pyrolysis conditions are harsh, and the equipment requirements are stringent. These defects in existing technologies severely limit their large-scale industrial application. Therefore, it is of great significance to develop a simple, efficient, low-cost, green and sustainable method for the resource utilization of waste plastic-based protective products derived from waste plastic-based protective products with high polyolefin content, and to apply the prepared porous carbon materials to the removal of emerging organic pollutants such as drugs and disinfectants in water bodies. Summary of the Invention

[0004] To overcome the shortcomings of existing technologies, this invention provides a simple, efficient, low-cost, green, and sustainable method for the resource utilization of waste materials derived from waste plastic-based protective products with high polyolefin content, and its application in the field of environmental remediation.

[0005] This invention is achieved through the following technical solution:

[0006] A method for the resource utilization of waste plastic-based protective equipment, which utilizes waste plastic-based protective equipment with high polyolefin content as a carbon source to prepare high-value nanoporous carbon materials to achieve its resource utilization, is characterized by the following steps:

[0007] (1) After disinfecting the waste plastic-based protective products and removing the non-carbonizable metal parts, the waste plastic-based protective products are initially mechanically crushed to form coarse fragments. The waste raw material fragments are then added to a mechanical crusher with a certain proportion of additive A and template agent precursor B for thorough crushing and mixing to form a mixed precursor to be carbonized.

[0008] (2) The mixed precursor obtained in step (1) is added into a rotary kiln and carbonized under certain heating conditions in a certain atmosphere to obtain carbonized products;

[0009] (3) The carbonized product obtained in step (2) is washed by reflux with nitric acid, filtered after washing, and the filtrate is collected. Then the filter cake is washed with water, and the water washing filtrate and acid washing filtrate are combined and collected. The water-washed filter cake is dried to obtain porous carbon material.

[0010] (4) The washing liquid collected in step (3) is evaporated under reduced pressure and crystallized to recover a mixture of auxiliary agent A and template agent precursor B, which can be used in the next round of carbon material preparation process.

[0011] A more preferred technical solution of the present invention is as follows:

[0012] Waste plastic-based protective equipment, which serves as a carbon source, contains more than 60% polypropylene.

[0013] In step (1), auxiliary agent A is ferric nitrate, template agent precursor B is magnesium nitrate, and the mass ratio of waste raw material fragments to auxiliary agent A and template agent precursor B is 1:0.2:0.4-1:2.5:8.

[0014] In step (2), the atmosphere of the carbonization process is either nitrogen or argon. The heating rate of the material in the rotary kiln is 2-10℃ / min, the maximum operating temperature is 500-900℃, and the holding time at the maximum operating temperature is 0.5-3h.

[0015] In step (3), the amount of nitric acid used (molar amount) is 1.05-1.5 times the total amount of nitrate in the auxiliary agent A and the template agent precursor B. The mass fraction of the nitric acid aqueous solution used is 10%-60%, the acid washing temperature is 30-80℃, and the washing time is 0.5-3 h.

[0016] The carbon materials prepared by the above-mentioned technical methods have a yield of 15%-45%, and the preparation process can achieve high content doping of surface oxygen species, with the oxygen content of the carbon materials being 3%-25%.

[0017] The porous carbon materials prepared by the above-mentioned technical methods have a specific surface area of ​​200-2000 m². 2 / g, with a concentrated pore size distribution range of 3-5nm.

[0018] The porous carbon material prepared by the above-mentioned technical method is applied in the continuous adsorption removal and dynamic regeneration of emerging organic pollutants such as pharmaceuticals and disinfectants in water. Among them, the emerging organic pollutants are one of acetaminophen, ibuprofen, triclosan, and p-chloro-m-xylenol, and the concentration of organic pollutants in wastewater is 10-500 ppm.

[0019] This invention ingeniously employs a "catalytic carbonization coupled with in-situ template" strategy to achieve high-yield preparation of nanoporous carbon materials using waste plastic-based protective products with high polyolefin content as a carbon source under normal pressure. Environmentally friendly ferric nitrate is used as a catalytic carbonization catalyst, effectively catalyzing the deposition of carbon from the waste plastic-based protective products during co-pyrolysis with the high polyolefin content. Simultaneously, the nano-iron oxide generated from the pyrolysis of ferric nitrate acts as an auxiliary template, together with the abundant nano-magnesium oxide template formed in-situ by the pyrolysis of magnesium nitrate, creating rich pore sites within the carbonization product. After acid leaching, this further forms a rich pore structure. The pyrolysis of nitrates with waste raw materials also achieves in-situ doping of nitrogen-containing species within the bulk phase of the carbon material. Furthermore, this invention uses nitric acid for hot reflux acid leaching of the carbonization product. This acid leaching process not only removes residual oxide templates and catalysts but also simultaneously recovers magnesium nitrate and ferric nitrate, and modifies the surface of the porous carbon material, forming abundant oxygen-containing functional groups on the carbon material surface, achieving a "three birds with one stone" effect. The prepared porous carbon possesses both abundant pore structure and nitrogen and oxygen doped species, providing rich enhanced adsorption sites for the adsorption and removal of various emerging organic pollutants such as phenols, which is conducive to the adsorption and removal of pollutants. At the same time, the abundant pore structure dominated by mesopores provides ideal mass transfer and diffusion channels for pollutant molecules, which is beneficial to the adsorption-regeneration performance of carbon materials.

[0020] The method of this invention has the advantages of simplicity, high efficiency, and sustainability. The template agent and catalyst used in the implementation process can be recycled, realizing the "turning waste into treasure" of waste plastic-based protective products. The prepared porous carbon material is applied to the removal of various phenolic drugs and emerging organic pollutants such as bactericides and disinfectants from water bodies. Attached Figure Description

[0021] The invention will now be further described with reference to the accompanying drawings.

[0022] Figure 1 This is a SEM image of WP-PC-1 in Example 1.

[0023] Figure 2The image shows the XPS spectrum of WP-PC-1 in Example 1.

[0024] Figure 3 The N2 adsorption-desorption isotherm diagram of WP-PC-1 in Example 1 is shown.

[0025] Figure 4 This is a pore size distribution diagram of WP-PC-1 in Example 3.

[0026] Figure 5 This is a pore size distribution diagram of WP-PC-2 in Example 3.

[0027] Figure 6 This is a pore size distribution diagram of PP-PC in Example 4.

[0028] Figure 7 The image shows the dynamic adsorption breakthrough curves of the acetaminophen solution from Example 10 over eight consecutive cycles.

[0029] Figure 8 The image shows the dynamic adsorption breakthrough curves of the p-chloro-meta-xylenol solution from Example 11, obtained after eight consecutive tests.

[0030] Figure 9 The diagram shows the dynamic adsorption evaluation device used in Examples 10 and 11. Detailed Implementation

[0031] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions in the embodiments of this invention will be clearly and completely described below, and the invention will be further explained in conjunction with the embodiments.

[0032] Example 1: A method for resource utilization of waste plastic-based protective products

[0033] Discarded N95 protective masks were used as the processing target. After disinfection and removal of non-carbonizable metal parts, the collected discarded N95 protective masks were shredded into plastic fragments using a shredder. Analysis of this batch of plastic fragments revealed that it contained 78% polypropylene, 14% polyethylene, and 8% nylon.

[0034] 100g of the above-mentioned plastic fragments, 216g of ferric nitrate nonahydrate, and 635g of magnesium nitrate hexahydrate were added to a mechanical pulverizer and thoroughly pulverized and mixed to form a well-mixed precursor for carbonization. This precursor mixture was added to a rotary kiln and carbonized under a nitrogen atmosphere at a rate of 5℃ / min to 700℃ for 1 hour to obtain the carbonized product. All of the carbonized product was transferred to a 2L flask, and 1150g of 40% nitric acid was added. The mixture was heated to 80℃ and refluxed for 2 hours. After reflux washing with nitric acid, the mixture was filtered, and the filtrate was collected. The filter cake was then rinsed with 300ml of water, and the water washing filtrate and acid washing filtrate were combined and collected. The washed filter cake was dried under reduced pressure at 120℃ to obtain 41.6g of porous carbon material, labeled WP-PC-1.

[0035] Example 2

[0036] The combined pickling and washing filtrates collected in Example 1 were subjected to vacuum evaporation, crystallization, and drying to recover a mixture of hydrated magnesium nitrate and ferric nitrate. This recovered mixed nitrate was then thoroughly pulverized and mixed with 100g of the same pre-treated waste protective mask plastic scraps from Example 1 in a mechanical pulverizer. The mixture was then processed using the same mixing, pyrolysis-carbonization, pickling-washing, and drying methods as in Example 1 to obtain 41.2g of porous carbon, labeled WP-PC-Re1. The combined pickling and washing filtrates were treated using the same methods to recover the mixed nitrate, which was then continuously reused as an additive and template agent precursor. All porous carbon preparation process conditions were consistent with those in Example 1. A total of five batches of continuous recycling experiments were investigated, and the carbon materials obtained in batches 2-5 were labeled WP-PC-Re2, WP-PC-Re3, WP-PC-Re4, and WP-PC-Re5, respectively. No fresh magnesium nitrate or ferric nitrate was added during the continuous recycling experiments.

[0037] Characterization of porous carbon materials: The key structural properties of the porous carbon materials prepared in Examples 1 and 2 were analyzed using SEM, XPS, elemental analysis, and N2 low-temperature physical adsorption-desorption techniques.

[0038] Table 1. Results of specific surface area, pore structure and yield analysis of porous carbon

[0039]

[0040] The analysis results in Table 1 show that the porous carbon derived from waste protective mask material prepared using the "catalytic carbonization coupled in-situ template" strategy with mixed nitrate additives exhibits excellent specific surface area and pore volume data. Combined with the N2 adsorption-desorption isotherm and pore size distribution results of WP-PC-1, it can be seen that the N2 adsorption-desorption isotherm of this porous carbon has a significant hysteresis loop and a clear pore channel concentration peak around 4 nm, indicating that it achieves the concentrated pore size distribution characteristic of ordered porous carbon, typical of disordered porous carbon materials. XPS analysis results of WP-PC-1 show that this carbon material simultaneously possesses O and N dopants, and elemental analysis results show that the oxygen content of this material is as high as 6.1%. The above-mentioned series of key physicochemical structural properties theoretically contribute positively to the adsorption and mass transfer of organic pollutants by this material as an adsorbent. Furthermore, the porous carbon yield is 41.6%, indicating that the "catalytic carbonization coupled in-situ template" strategy can effectively and efficiently convert polyolefins, which are not easily carbonized, into solid carbon materials. More notably, without any initial addition of fresh magnesium nitrate or ferric nitrate, the five batches of porous carbon materials continuously prepared using only repeatedly recycled mixed nitrates exhibited a similar specific surface area and pore volume to WP-PC-1 prepared using initial fresh magnesium nitrate or ferric nitrates. Furthermore, the yield of the carbon materials remained relatively stable. This indicates that the "catalytic carbonization coupled with in-situ template" strategy using mixed nitrate additives has good recyclability and can effectively reduce the preparation cost of porous carbon.

[0041] Example 3

[0042] Discarded protective suits were used for processing. After disinfection and removal of non-carbonizable metal parts, the collected suits were shredded into plastic fragments using a shredder. Analysis of this batch of plastic fragments revealed that it contained 83% polypropylene, 12% polyethylene, and 5% nylon.

[0043] Following the preparation method in Example 1: 100g of the aforementioned plastic fragments, 216g of ferric nitrate nonahydrate, and 635g of magnesium nitrate hexahydrate were added to a mechanical pulverizer for thorough pulverization and mixing to form a homogeneous precursor for carbonization. This precursor mixture was then added to a rotary kiln and carbonized under a nitrogen atmosphere at a rate of 5°C / min to 700°C for 1 hour, yielding the carbonized product. All of the carbonized product was transferred to a 2L flask, and 1150g of 40% nitric acid was added. The mixture was heated to 80°C and refluxed for 2 hours. After reflux washing with nitric acid, the mixture was filtered, and the filtrate was collected. The filter cake was then rinsed with 300ml of water, and the water-washed filtrate and acid-washed filtrate were combined and collected. The washed filter cake was dried under reduced pressure at 120°C to obtain 41.1g of porous carbon material, with a yield of 41.1%, labeled as WP-PC-2.

[0044] Characterization of porous carbon materials: Key structural properties of the prepared WP-PC-2 were analyzed using elemental analysis and low-temperature physical adsorption-desorption of N2.

[0045] The specific surface area and total pore volume of WP-PC-2 are 1701.43 m². 2 / g and 1.99cm 3 The yield of WP-PC-2 was similar to that of WP-PC-1, with a pore size distribution map showing a clear concentrated peak around 4 nm, consistent with WP-PC-1. Elemental analysis revealed oxygen and nitrogen contents of 6.11% and 4.23%, respectively, indicating effective in-situ doping of nitrogen and oxygen species during preparation. Furthermore, the yield of WP-PC-2 was 41.1%, similar to WP-PC-1, maintaining a high level. This demonstrates the good versatility of the mixed nitrate "catalytic carbonization coupled in-situ template" preparation strategy for synthesizing porous carbon materials derived from waste plastic-based protective equipment with high polyolefin content.

[0046] Example 4: Verification Experiment

[0047] Polypropylene masterbatch was used as the carbon source. The same preparation method as in Example 1 was used: 100g of polypropylene masterbatch, 216g of ferric nitrate nonahydrate, and 635g of magnesium nitrate hexahydrate were added to a mechanical pulverizer for thorough pulverization and mixing to form a homogeneous precursor for carbonization. This precursor mixture was added to a rotary kiln and carbonized under a nitrogen atmosphere at a rate of 5°C / min to 700°C for 1 hour to obtain the carbonized product. All the carbonized product was transferred to a 2L flask, and 1150g of 40% nitric acid was added. The mixture was heated to 80°C and refluxed for 2 hours. After reflux washing with nitric acid, the mixture was filtered, and the filtrate was collected. The filter cake was then rinsed with 300ml of water, and the water washing filtrate and acid washing filtrate were combined and collected. The washed filter cake was dried under reduced pressure at 120°C to obtain 40.5g of porous carbon material, with a yield of 40.5%, labeled as PP-PC.

[0048] Characterization of porous carbon materials: Key structural properties of the prepared PP-PC were analyzed using elemental analysis and low-temperature physical adsorption-desorption of N2.

[0049] The specific surface area and total pore volume of PP-PC are 1705.25 m². 2 / g and 2.01cm 3The yield of PP-PC was similar to that of WP-PC-1 and WP-PC-2, with a yield of 40.5%. Elemental analysis showed that the oxygen and nitrogen contents of PP-PC reached 6.14% and 4.27%, respectively, indicating that effective in-situ doping of nitrogen and oxygen species was also achieved during the preparation process. Notably, the yield of PP-PC remained high at 40.5%, further validating the high applicability of the mixed nitrate "catalytic carbonization coupled in-situ template" preparation strategy for preparing porous carbon derived from polyolefin-based raw materials with non-carbon-forming properties.

[0050] Example 5 (Comparative Experiment 1):

[0051] The same batch of pre-treated waste protective mask plastic scraps from Example 1 were used as raw materials. The preparation method was as follows: 100g of the aforementioned plastic scraps were directly crushed in a mechanical pulverizer to form a precursor for carbonization. This precursor was added to a rotary kiln and carbonized under a nitrogen atmosphere at a rate of 5°C / min to 700°C for 1 hour, yielding a very small amount of carbonized product. This is in stark contrast to Examples 1, 2, and 3. All of the carbonized product was transferred to a flask and treated with the same acid washing and water washing as in Example 1. After treatment and filtration, the amount of carbon material obtained was very small; after drying, only 0.89g of solid was obtained, with a calculated yield of only 0.89%, labeled WP-C-0.

[0052] The results of the above comparative experiments show that, using the same carbon source, when the raw materials are directly carbonized without using the "catalytic carbonization coupled in-situ template" strategy of mixed nitrate additives, the waste protective mask material with high polyolefin content exhibits its "non-carbon-forming characteristic" and cannot be directly and efficiently synthesized into porous carbon materials.

[0053] Example 6 (Comparative Experiment 2):

[0054] The same polypropylene masterbatch as in Example 4 was used directly as the carbon source. The preparation method was the same as in Example 5, and the "catalytic carbonization coupled in-situ template" strategy using a mixed nitrate additive of magnesium nitrate and ferric nitrate was not used; the polypropylene masterbatch was directly subjected to pyrolysis carbonization. After carbonization, there were virtually no carbonization products remaining in the rotary kiln tube. This further verifies the characteristic that polypropylene materials tend to pyrolyze into small molecule hydrocarbons and do not deposit into carbon during direct heating carbonization at atmospheric pressure.

[0055] Example 7 (Comparative Experiment 3):

[0056] The raw material was pre-treated waste protective mask plastic scraps from the same batch as in Example 1. The preparation method was as follows: 100g of the above plastic scraps and 635g of magnesium nitrate hexahydrate were added to a mechanical pulverizer and thoroughly pulverized and mixed to form a well-mixed precursor for carbonization. The carbonization product was obtained under the same pyrolysis-carbonization conditions as in Example 1. The carbonization product was treated using the same acid washing and water washing methods as in Example 1. After treatment, filtration, and drying, the amount of carbon product obtained was small, only 3.34g. It was labeled WP-PC-S1.

[0057] The key structural properties of WP-PC-S1 were analyzed using N2 low-temperature physical adsorption-desorption techniques. The results show that the specific surface area and total pore volume of WP-PC-S1 are 814.12 m² / s. 2 / g and 0.69cm 3 The yield of WP-PC-S1 was significantly lower than that of WP-PC-1 ( / g). The calculated yield of WP-PC-S1 was very low, only 3.34%. This indicates that while magnesium nitrate can indeed create a certain porous structure during pyrolysis by generating nano-magnesium oxide templates in situ, it is impossible to achieve the specific surface area and pore structure level of WP-PC-1 in Example 1 using only magnesium nitrate. More importantly, the carbon yield was very low without the addition of ferric nitrate, indicating that magnesium nitrate or in-situ generated magnesium oxide cannot effectively catalyze carbonization; ferric nitrate or in-situ generated ferric oxide is the effective component for catalytic carbonization. Furthermore, the in-situ generated nano-ferric oxide also acted as an auxiliary template agent, synergistically creating a high specific surface area and abundant pore structure in the porous carbon material with the in-situ generated nano-magnesium oxide.

[0058] Example 8 (Comparative Experiment 4):

[0059] The same batch of pre-treated waste protective mask plastic scraps from Example 1 were used as raw materials. The preparation method was as follows: 100g of the above plastic scraps and 216g of ferric nitrate nonahydrate were added to a mechanical pulverizer and thoroughly pulverized and mixed to form a well-mixed precursor for carbonization. The carbonization product was obtained under the same pyrolysis-carbonization conditions as in Example 1. The carbonization product was treated using the same acid washing and water washing methods as in Example 1. After treatment, filtration, and drying, the amount of carbonized product obtained was 25.39g. It was labeled as WP-PC-S2.

[0060] The key structural properties of WP-PC-S2 were analyzed using N2 low-temperature physical adsorption-desorption techniques. The results show that the specific surface area and total pore volume of WP-PC-S2 are 197.95 m² / s. 2 / g and 0.68cm 3 / g, significantly lower than WP-PC-1. The calculated yield of WP-PC-S2 was 25.39%. Combined with the experimental results of Example 7, it can be further verified that ferric nitrate or in-situ generated ferric oxide is the main active component for catalytic carbonization during pyrolysis, playing a crucial role in the yield of carbonization products; while magnesium nitrate plays a key role in pore formation by in-situ generating nano-magnesium oxide templates during pyrolysis; in addition, in-situ generated nano-ferric oxide also acts as an auxiliary template agent, synergistically creating a high specific surface area and abundant pore structure in porous carbon materials with in-situ generated nano-magnesium oxide.

[0061] Example 9 (Comparative Experiment 5):

[0062] The same batch of pre-treated waste protective mask plastic scraps from Example 1 were used as raw materials, and the raw materials were mixed and carbonized in complete accordance with the preparation method in Example 1.

[0063] The obtained carbonization product was divided into two portions. One portion was washed thoroughly by reflux for 2 hours with 40% excess sulfuric acid heated to 80°C. The other portion was washed thoroughly by reflux for 2 hours with 35% excess hydrochloric acid heated to 80°C. After filtration and acid washing, the resulting filter cakes were washed with water and dried. The obtained porous carbon materials were labeled as WP-PC-S3 and WP-PC-S4, respectively.

[0064] Characterization of porous carbon materials: The key structural properties of the prepared WP-PC-S3 and WP-PC-S4 were analyzed by elemental analysis and N2 low-temperature physical adsorption-desorption techniques.

[0065] The analysis results show that the specific surface area and total pore volume of WP-PC-S3 are 1710.33 m². 2 / g and 2.01cm 3 The specific surface area and total pore volume of WP-PC-S4 are 1708.64 m² / g. 2 / g and 2.00cm 3 The nitrogen and oxygen contents of WP-PC-S3 and WP-PC-S4 were 0.78% and 1.83% and 0.65% and 1.47% respectively, which were significantly lower than those of WP-PC-1, especially the oxygen content. This indicates that nitric acid washing can not only convert magnesium and iron oxides in the carbonization products into nitrates for recovery, but also achieve efficient doping modification of nitrogen and oxygen species on the porous carbon surface.

[0066] Example 10: Continuous Adsorption Removal and Dynamic Regeneration Evaluation Experiment of Emerging Organic Pollutants such as Pharmaceuticals and Bactericides in Water 1

[0067] A 50 mg / L aqueous solution of acetaminophen was prepared. 0.1018 g of WP-PC-1 prepared in Example 1 was accurately weighed, and a small amount of anhydrous ethanol was added to form a slurry. This slurry was then packed into a 50 mm long, 4.6 mm inner diameter stainless steel column using a wet packing method, with both ends sealed with clean quartz sand. The 50 mg / L aqueous solution of acetaminophen was continuously pumped into the stainless steel column using a horizontal flow pump at a flow rate of 3 mL / min. The concentration of acetaminophen in the effluent was monitored in real time using a UV-Vis spectrophotometer. The detection wavelength for acetaminophen was 243 nm. The continuous adsorption operation temperature was 25 °C. After adsorption saturation, the carbon adsorbent in the column was dynamically regenerated using anhydrous methanol. During regeneration, the column was placed in a water bath at a constant temperature of 60 °C. The desorption flow rate was 1.5 mL / min. After the desorption and regeneration process was completed, dynamic adsorption evaluation was performed again. The above dynamic adsorption-regeneration cycle was repeated a total of 8 times. Draw a dynamic penetration curve.

[0068] Evaluation results show that WP-PC-1 exhibits excellent dynamic adsorption capacity and regenerability in 8 consecutive dynamic adsorption-regeneration cycles. After 8 consecutive adsorption-regeneration cycles, the dynamic adsorption performance did not change significantly from the initial state, demonstrating good potential for practical application.

[0069] Example 11: Continuous Adsorption Removal and Dynamic Regeneration Evaluation Experiment of Emerging Organic Pollutants such as Pharmaceuticals and Bactericides in Water 2

[0070] A 100 mg / L aqueous solution of p-chloro-m-xylenol was prepared. 0.1005 g of WP-PC-2 prepared in Example 2 was accurately weighed, and a small amount of anhydrous ethanol was added to form a slurry. This slurry was then packed into a 50 mm long, 4.6 mm inner diameter stainless steel column using a wet packing method, with both ends sealed with clean quartz sand. The 100 mg / L aqueous solution of p-chloro-m-xylenol was continuously pumped into the stainless steel packed column using a horizontal flow pump at a flow rate of 3 mL / min. The concentration of p-chloro-m-xylenol in the effluent was monitored in real time using a UV-Vis spectrophotometer. The detection wavelength for p-chloro-m-xylenol was 279 nm. The continuous adsorption operating temperature was 25 °C. After adsorption saturation, the carbon adsorbent in the packed column was dynamically regenerated using anhydrous methanol. During regeneration, the packed column was placed in a water bath at a constant temperature of 60 °C. The desorption flow rate was 1.5 mL / min. After the desorption and regeneration process was completed, dynamic adsorption evaluation was performed again. Repeat the above dynamic adsorption-regeneration cycle a total of 8 times. Plot the dynamic breakthrough curve.

[0071] The evaluation results show that, similar to WP-PC-1 in Example 10, WP-PC-2 exhibits excellent dynamic adsorption capacity and regenerability in 8 consecutive dynamic adsorption-regeneration cycles. After 8 consecutive adsorption-regeneration cycles, the dynamic adsorption performance did not change significantly from the initial state, thus demonstrating good potential for practical application.

Claims

1. A method for the resource utilization of waste plastic-based protective equipment, which utilizes waste plastic-based protective equipment with high polyolefin content as a carbon source to prepare high-value nanoporous carbon materials to achieve efficient resource utilization, characterized by the following steps: (1) After disinfecting and removing non-carbonizable metal parts from waste plastic-based protective equipment, the equipment is initially mechanically crushed to form coarse fragments. These waste fragments are then mixed with a certain proportion of additive A and template agent precursor B in a mechanical crusher to form a mixed precursor to be carbonized. Additive A is ferric nitrate, and template agent precursor B is magnesium nitrate. The mass ratio of waste fragments to additive A and template agent precursor B is 1:0.2:0.4-1:2.5:

8. (2) The mixture processed in step (1) The obtained mixed precursors are added to a rotary kiln and carbonized under a certain atmosphere and at a certain temperature to obtain carbonized products; (3) The carbonized products obtained in step (2) are washed by reflux with nitric acid, filtered after washing, and the filtrate is collected. The filter cake is then washed with water, and the water washing filtrate and acid washing filtrate are combined and collected. The water-washed filter cake is dried to obtain porous carbon materials. The yield of the prepared carbon materials is 15%-45%, the oxygen content of the carbon materials is 3%-25%, the specific surface area is 200-2000 m2 / g, and the pore size distribution range is 3-5nm; (4) The washing liquid collected in step (3) is evaporated under reduced pressure and crystallized to recover a mixture of auxiliary agent A and template agent precursor B, which can be used in the next round of carbon material preparation process.

2. The method for resource utilization of waste plastic-based protective equipment according to claim 1, characterized in that: Waste plastic-based protective equipment, which serves as a carbon source, contains more than 60% polypropylene.

3. The method for resource utilization of waste plastic-based protective equipment according to claim 1, characterized in that: In step (2), the atmosphere of the carbonization process is either nitrogen or argon. The heating rate of the material in the rotary kiln is 2-10℃ / min, the maximum operating temperature is 500-900℃, and the holding time at the maximum operating temperature is 0.5-3h.

4. The method for resource utilization of waste plastic-based protective equipment according to claim 1, characterized in that: In step (3), the amount of nitric acid used by molar is 1.05-1.5 times the total amount of nitrate in auxiliary agent A and template agent precursor B. The mass fraction of the nitric acid aqueous solution used is 10%-60%, the pickling temperature is 30-80℃, and the washing time is 0.5-3 h.

5. The application of the porous carbon material prepared by the method according to claim 1 in the continuous adsorption removal and dynamic regeneration of emerging organic pollutants such as drugs and disinfectants in water.

6. The application according to claim 5, characterized in that: The emerging organic pollutant is one of acetaminophen, ibuprofen, triclosan, and chlorometa-xylenol, with a concentration of 10-500 ppm in the wastewater.

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