Agaric-based porous biomass carbon material and preparation method thereof

Abstract

The invention belongs to the technical field of porous biomass carbon materials, and discloses an agaric-based porous biomass carbon material and a preparation method thereof. The preparation method comprises the following steps: S1, primarily cleaning agaric, and then drying for 2 hours at the temperature of 50-70 DEG C; s2, the pretreated agaric is mixed with an activating agent, and carbonization treatment is conducted for 1-3 h at the temperature of 600-900 DEG C under nitrogen protection; and S3, sequentially carrying out suction filtration and washing on a product obtained in the step S2 by using absolute ethyl alcohol and deionized water, and then drying the product at the temperature of 50-70 DEG C until the weight is constant, so as to obtain the agaric-based porous biomass carbon material. According to the method, the agaric biomass is subjected to simplified pyrolysis treatment in a limited oxygen environment, and the steps of secondary cleaning and drying are combined, so that the porous carbon material with an excellent pore structure can be efficiently synthesized; the material can significantly improve the adsorption capacity of iodine, can recover the adsorption performance through a simple regeneration process, and solves the problem that a traditional adsorption material is difficult to reuse.

Description

Technical Field

[0001] The present invention belongs to the technical field of porous bio-carbon materials, and in particular relates to a wood ear-based porous biomass carbon material and a preparation method thereof. Background Art

[0002] How to deal with nuclear waste in an efficient and environmentally friendly way, especially the radioactive iodine produced in nuclear accidents, has become a major challenge in the field of technology research and development. The presence of radioactive iodine in nuclear waste poses a serious threat to the environment and human health, especially 131 I, whose half-life is only 8 days, 129 I has an extremely long half-life, up to 1.57×10 7 However, after a nuclear leak, radioactive iodine accumulates through the food chain, causing profound impacts on ecosystems and human health. Therefore, how to efficiently remove radioactive iodine has become a key research topic in the fields of nuclear energy utilization and environmental governance.

[0003] Solid-phase adsorption, a common iodine capture technique, has been widely adopted in both industrial and scientific research. This method relies on the porous structure and surface functional groups of the adsorbent material to capture iodine in the gas or liquid phase through chemical adsorption, physical adsorption, or a combination of both. Common adsorbent materials include activated carbon and zeolites, which are typically loaded with organic amines through impregnation to enhance their iodine adsorption capacity. However, these adsorbents also have limitations: first, organic amines readily sublime, resulting in a decrease in adsorption capacity; second, the heat released during adsorption can ignite fires, especially for organic amines with low ignition points; and finally, impregnated carbon materials are susceptible to aging and weathering, and their regeneration ability is poor, limiting their reuse and potentially causing secondary pollution. Some studies have attempted to load activated silver onto solid supports to enhance iodine adsorption, but the instability of the resulting silver iodide has hindered the practical application of this approach. In recent years, new porous materials such as conjugated microporous polymers, covalent organic frameworks (COFs) and metal-organic frameworks (MOFs) have shown potential in iodine capture, but due to the complex synthesis process and high cost of these materials, they still face challenges in large-scale application. Summary of the Invention

[0004] In light of this, and to overcome the limitations of existing adsorption materials, the present invention aims to provide a wood ear-based porous biomass carbon material and its preparation method. By subjecting wood ear biomass to a simplified pyrolysis treatment in a limited oxygen environment, combined with secondary cleaning and drying steps, a porous carbon material with an excellent pore structure can be efficiently synthesized, significantly enhancing its iodine adsorption capacity. This material also exhibits good structural stability and can restore its adsorption properties through a simple regeneration process, addressing the difficulty of reusing traditional adsorption materials.

[0005] To achieve the above object, the present invention provides the following technical solutions: A method for preparing a fungus-based porous biomass carbon material, comprising: S1. Preliminary cleaning of the fungus, followed by drying at 50-70°C for 2 hours; S2. The pretreated fungus is mixed with an activator and carbonized at a temperature of 600 to 900°C for 1 to 3 hours under nitrogen protection; S3. The product obtained in step S2 is filtered and washed with anhydrous ethanol and deionized water in sequence, and then dried at a temperature of 50 to 70° C. to a constant weight to obtain a fungus-based porous biomass carbon material.

[0006] Preferably, in step S1, the preliminary cleaning of the fungus comprises: soaking the fungus in deionized water and anhydrous ethanol in sequence, and performing ultrasonic cleaning.

[0007] Preferably, in step S1, the preliminary cleaning of the fungus includes: Use deionized water to rinse the fungus for the first time; Soak the fungus in deionized water, ultrasonically clean it for 5 to 20 minutes, and rinse it twice with deionized water; Soak the fungus in anhydrous ethanol, clean it with ultrasonic cleaning for 1 to 3 hours, and rinse it again with deionized water.

[0008] Preferably, in step S2, the activator is zinc chloride.

[0009] Preferably, in step S2, the pretreatment is to grind the fungus and the activator into powder respectively.

[0010] Preferably, in step S2, the mixing mass ratio of the fungus to the activator is 1:1-3.

[0011] Preferably, in step S2, under nitrogen protection, the temperature is raised to 600-900° C. at a heating rate of 3-8° C. / min.

[0012] Preferably, in step S3: first, the product obtained by the treatment in step S2 is filtered and washed 1 to 3 times with anhydrous ethanol; then, the product is filtered and washed with deionized water until the pH value of the product reaches 7.

[0013] Preferably, in step S3, the drying time is 12 hours.

[0014] The present invention also provides a fungus-based porous biomass carbon material prepared by the above preparation method.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The present preparation method utilizes widely available and biodegradable wood ear mushroom biomass. Through a simple pyrolysis process in a limited oxygen environment, combined with secondary cleaning and drying steps, a porous carbon material with an excellent pore structure is successfully synthesized. This preparation method is simple, does not require the use of toxic or hazardous chemicals, is highly safe, and is suitable for large-scale production.

[0016] The material produced by this invention has a large specific surface area and abundant pore volume, effectively providing more adsorption sites, thereby significantly improving iodine adsorption capacity. It is widely applicable in a variety of applications, including environmental protection and pollutant adsorption, particularly in nuclear waste treatment and the removal of radioactive iodine in nuclear accidents. Furthermore, the porous carbon material has good structural stability and can restore its adsorption performance through a simple regeneration process, solving the problem of traditional adsorption materials being difficult to reuse. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the XRD pattern of the wood ear-based porous biomass carbon material prepared in Example 2; Figure 2 Surface morphology of the fungus-based porous biomass carbon material prepared in Example 2 at different magnifications; Figure 3 N2 adsorption-desorption isotherms and pore size distribution curves of the wood ear-based porous biomass carbon materials prepared in Example 2, Comparative Example 1 and Comparative Example 2; Figure 4 This is a comparison chart of the Fourier transform infrared spectrum, Raman spectrum and thermogravimetric analysis spectrum of the wood ear-based porous biomass carbon material prepared in Example 2. DETAILED DESCRIPTION

[0018] To further understand the content of the present invention, the present invention is described in detail in conjunction with the accompanying drawings and embodiments. The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the content disclosed in the specification, so that people familiar with the technology can understand and read them. They are not used to limit the limitations of the implementation of the present invention and therefore have no technical significance. Any structural modifications, changes in proportional relationships, or adjustments in size should still fall within the scope of the technical content disclosed in the present invention without affecting the efficacy and objectives that can be achieved by the present invention. At the same time, terms such as "upper", "lower", "left", "right", and "middle" used in this specification are only for ease of description and are not used to limit the scope of implementation. Changes or adjustments in their relative relationships should also be considered as the scope of implementation of the present invention without substantially changing the technical content. It should be noted that the terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way are interchangeable where appropriate for the embodiments of the present application described herein. Example 1

[0019] A method for preparing a fungus-based porous biomass carbon material, comprising: S1. Cleaning and drying of carbon source materials S11. Rinse the surface of 10g of dried fungus with deionized water to remove dust and other impurities. Alternatively, deionized water and anhydrous ethanol may be used to rinse the surface of the fungus alternately. S12. Soak the fungus in deionized water and perform ultrasonic cleaning for 5 minutes. Remove and rinse with deionized water for the second time. S13. Soak the fungus in anhydrous ethanol and ultrasonically clean it for 2 hours. Remove it and rinse it again with deionized water. S14. Place the cleaned fungus in a constant temperature drying oven at 60°C for 2 hours, and then cool naturally to room temperature.

[0020] S2. Heat and react with the activator (carbonize the wood ear through high temperature reaction under the action of the activator) S21 weighed 20g of solid zinc chloride with a chemical purity of 99.9% and ground it into a uniform fine powder using an agate mortar; S22. Weigh 6 to 20 g of the dried fungus processed in step S1, ensuring a mass ratio of fungus to zinc chloride of 1:1.8, and grind into a uniform fine powder using an agate mortar; S23. The zinc chloride powder and the fungus powder were evenly mixed and placed in a quartz crucible with a lid; S24. Place the crucible in a tubular furnace with a nitrogen (99.9%) protective atmosphere, heat it to 900°C at a heating rate of 4°C / min, and maintain it at this temperature for 1.5 hours for carbonization treatment. After the reaction is completed, cool it naturally to room temperature under a nitrogen protective atmosphere.

[0021] S3. Secondary cleaning and drying of porous biomass carbon materials (to remove substances such as the activator zinc chloride that clog the gaps, the carbonized wood ear mushrooms are further cleaned and dried) S31. The product obtained in step S2 was filtered once using anhydrous ethanol; of course, in this step, deionized water may be used instead of anhydrous ethanol; S32. Continue filtration with deionized water until the pH value of the product reaches 7; S33. Place the cleaned product in an oven, set the temperature to 50°C, and dry it for 12 hours to constant weight to obtain a wood ear-based porous biomass carbon material. Example 2

[0022] A method for preparing a fungus-based porous biomass carbon material, comprising: S1. Cleaning and drying of carbon source materials S11. Rinse the surface of 10g of dried fungus with deionized water to remove dust and other impurities. Alternatively, deionized water and anhydrous ethanol may be used to rinse the surface of the fungus alternately. S12. Soak the fungus in deionized water and perform ultrasonic cleaning for 10 minutes. Remove and rinse with deionized water for the second time. S13. Soak the fungus in anhydrous ethanol and ultrasonically clean it for 2 hours. Remove it and rinse it again with deionized water. S14. Place the cleaned fungus in a constant temperature drying oven at 60°C for 2 hours, and then cool naturally to room temperature.

[0023] S2. Heat and react with the activator (carbonize the wood ear through high temperature reaction under the action of the activator) S21 weighed 20g of solid zinc chloride with a chemical purity of 99.9% and ground it into a uniform fine powder using an agate mortar; S22. Weigh 6 to 20 g of the dried fungus processed in step S1, ensuring a mass ratio of fungus to zinc chloride of 1:2, and grind into a uniform fine powder using an agate mortar; S23. The zinc chloride powder and the fungus powder were evenly mixed and placed in a quartz crucible with a lid; S24. Put the crucible into a tube furnace which is connected to a nitrogen (99.9%) protective atmosphere, and heat it to 800℃ at a heating rate of 5℃ / min, and keep it at this temperature for 2h for carbonization treatment, and then naturally cool it to room temperature under the nitrogen protective atmosphere.

[0024] S3. Secondary washing and drying of the porous biomass carbon material (to remove the blocking substances such as zinc chloride, the activated agent, further wash and dry the carbonized agaric) S31. Use anhydrous ethanol to extract filter the product obtained in step S2 for 3 times; of course, in this step, deionized water can be used instead of anhydrous ethanol; S32. Continue to extract filter using deionized water until the pH value of the product is 7; S33. Put the washed product into an oven, set the temperature to 60℃, and dry it to constant weight for 12h to obtain an agaric-based porous biomass carbon material. Example 3

[0025] A method for preparing an agaric-based porous biomass carbon material, comprising: S1. Washing and drying of the carbon source material S11. Primary washing of the surface of dry agaric with a net weight of 10g, using deionized water to remove dust and other impurities on the surface of the agaric. Of course, in this step, deionized water and anhydrous ethanol can be used alternately to remove dust and other impurities on the surface of the agaric; S12. Soak the agaric in deionized water and ultrasonically wash it for 20min, and then rinse it again with deionized water; S13. Soak the agaric in anhydrous ethanol and ultrasonically wash it for 3h, and then rinse it again with deionized water; S14. Put the washed agaric into a constant-temperature drying oven, set the temperature to 70℃, and dry it for 2h, and then naturally cool it to room temperature.

[0026] S2. Co-heating reaction with the activated agent (carbonize the agaric by high-temperature reaction under the action of the activated agent) S21. Weigh 20g of chemically pure zinc chloride solid with a purity of 99.9%, and grind it into a uniform fine powder using a corundum mortar; S22. Weigh 6-20g of agaric treated and dried in step S1, and ensure that the mass ratio of agaric to zinc chloride is 1:2.2, and grind it into a uniform fine powder using a corundum mortar; S23. Mix the zinc chloride powder and agaric powder uniformly, and put them into a covered quartz crucible; S24. Put the crucible into a tube furnace with nitrogen (99.9%) protective atmosphere, and heat to 600℃ at a heating rate of 6℃ / min, and keep the temperature for 2.5h for carbonization treatment, and then naturally cool to room temperature under nitrogen protective atmosphere.

[0027] S3. Secondary cleaning and drying of the porous biomass carbon material (to remove the blocking substances such as zinc chloride, the activated agent, and further clean and dry the carbonized agaric) S31. Use anhydrous ethanol to extract filter the product obtained in step S2 twice; of course, deionized water can be used instead of anhydrous ethanol in this step; S32. Continue to extract filter using deionized water until the pH value of the product is 7; S33. Put the cleaned product into an oven, set the temperature to 70℃, and dry for 12h to constant weight to obtain an agaric-based porous biomass carbon material.

[0028] Based on Example 2, the following comparative examples are also provided: Comparative Example 1 (the difference from Example 2 is that no activated agent is used) A method for preparing an agaric-based porous biomass carbon material, comprising: S1. Cleaning and drying of the carbon source material Primary rinse the surface of the dry agaric with a net weight of 10g using deionized water to remove dust and other impurities on the surface of the agaric. Of course, deionized water and anhydrous ethanol can be used alternately to rinse and remove dust and other impurities on the surface of the agaric in this step; Soak the agaric in deionized water and ultrasonically clean for 10min, and then rinse it again with deionized water after taking it out; soak the agaric in anhydrous ethanol and ultrasonically clean for 2h, and then rinse it again with deionized water after taking it out; Put the cleaned agaric into a constant temperature drying oven, set the temperature to 60℃, and dry for 2h, and then naturally cool to room temperature.

[0029] S2. Heating and carbonization reaction (the difference from Example 2 is that no activated agent is used) Weigh 6-20g of agaric treated and dried in step S1, and grind it into a uniform fine powder with a corundum mortar; Put the agaric powder into a covered quartz crucible; Put the crucible into a tube furnace with nitrogen (99.9%) protective atmosphere, and heat to 800℃ at a heating rate of 5℃ / min, and keep the temperature for 2h for carbonization treatment, and then naturally cool to room temperature under nitrogen protective atmosphere.

[0030] S3. Secondary cleaning and drying of the porous biomass carbon material The product obtained in step S2 was filtered three times using anhydrous ethanol; of course, in this step, deionized water can be used instead of anhydrous ethanol; Continue to filter with deionized water until the pH value of the product reaches 7; The cleaned product was placed in an oven, the temperature was set at 60° C., and dried for 12 h to a constant weight to obtain a wood ear-based porous biomass carbon material.

[0031] Comparative Example 2 (the difference from Example 2 is that secondary cleaning and drying are not performed) A method for preparing a fungus-based porous biomass carbon material, comprising: S1. Cleaning and drying of carbon source materials The surface of 10 g of dried fungus was initially rinsed with deionized water to remove dust and other impurities on the surface of the fungus. Of course, in this step, deionized water and anhydrous ethanol can also be used to alternately rinse to remove dust and other impurities on the surface of the fungus; Soak the fungus in deionized water and perform ultrasonic cleaning for 10 minutes, then take it out and rinse it again with deionized water; soak the fungus in anhydrous ethanol and perform ultrasonic cleaning for 2 hours, then take it out and rinse it again with deionized water; Place the cleaned fungus in a constant temperature drying oven, set the temperature to 60°C, dry for 2 hours, and cool naturally to room temperature.

[0032] S2. Heat reaction with activator Weigh 20 g of solid zinc chloride with a chemical purity of 99.9% and grind it into a uniform fine powder using an agate mortar; Weigh 6-20 g of the dried fungus processed in step S1, ensuring a mass ratio of fungus to zinc chloride of 1:2, and grind into a uniform fine powder using an agate mortar and pestle; Mix zinc chloride powder and wood ear powder evenly and put them into a quartz crucible with a lid; The crucible was placed in a tubular furnace with a nitrogen (99.9%) protective atmosphere, heated to 800°C at a heating rate of 5°C / min, and kept at this temperature for 2 hours for carbonization treatment. After the reaction was completed, it was naturally cooled to room temperature under a nitrogen protective atmosphere to obtain the wood ear-based porous biomass carbon material.

[0033] ① Regarding the wood ear-based porous biomass carbon material prepared in Example 2 above: The XRD analysis revealed Figure 1The XRD pattern shown: The wood ear-based porous biomass carbon material sample prepared in Example 2 is labeled BF-Z. Diffraction envelope peaks appear at 23.5° and 43.6°, respectively. These peaks correspond to the (002) and (100) crystal planes of amorphous graphite, indicating that the material is amorphous carbon. Only diffraction peaks of amorphous carbon are observed in the XRD pattern. Due to the secondary cleaning, no diffraction peaks of the activator ZnCl2 are observed. This further proves that the product cleaning in step S3 has been very thorough, and the activator ZnCl2 has been completely removed and does not remain in the final wood ear-based porous biomass carbon product.

[0034] Figure 2 The surface morphology of BF-Z is shown. Scanning electron microscopy (SEM) images at different magnifications clearly reveal the material's rich pore structure. A detailed analysis of the pore size distribution in the SEM images reveals that the pore structure of BF-Z is primarily composed of micropores, with a small amount of mesopores. Further calculations indicate that the average pore diameter of the BF-Z material is approximately 6.46 mm.

[0035] Figure 4 Comparative Fourier transform infrared (FT-IR), Raman spectroscopy, and thermogravimetric analysis (TGA) spectra of the wood ear-based porous biomass carbon material prepared in Example 2 before and after iodine vapor capture are presented. Iodine vapor adsorption experiments show that the BF-Z material has an iodine vapor adsorption capacity of up to 2893 mg / g, with adsorption values ​​consistently ranging from 2129 to 2893 mg / g across multiple experiments.

[0036] Figure 4 In (a), before iodine adsorption, the -1 、1528cm -1 and 1137cm -1 The stretching vibration peaks of C-OH, C=C and CO were observed at the ions, respectively. After iodine adsorption, the characteristic peak of C=C shifted significantly to a higher wavenumber, indicating that charge transfer occurred between C=C and iodine, confirming the existence of chemical adsorption. Figure 4 (b) shows the Raman spectra of BF-Z material before and after iodine adsorption. After iodine adsorption, the Raman spectrum at 169 cm -1 and 106cm -1 I5 appears - and I3 - The characteristic peaks of iodine indicate that iodine is mainly in the form of I5 - and I3 - The forms of iodine exist in the fungus-based porous biomass carbon material (BF-ZI) after iodine adsorption. These changes reveal the important role of chemical adsorption in the iodine capture process. Figure 4(c) Shows the thermal stability and adsorption behavior of BF-Z before and after iodine capture. Notably, BF-ZI exhibits two distinct weight loss stages within the temperature range of 81.6°C to 750°C. The first stage, occurring between 81.6°C and 300°C, results in a 57% mass loss, likely due to both iodine physical adsorption (81.6°C to the iodine sublimation temperature of 184°C) and iodine chemical adsorption (184°C to 300°C). The second weight loss stage, occurring after 500°C, is likely due to the deep carbonization of the biomass carbon material. Ultimately, the total mass of BF-ZI decreases by 65.7%. These results confirm that the iodine adsorption mechanism of BF-Z material involves the synergistic effects of physical and chemical adsorption.

[0037] ② Regarding the fungus-based porous biomass carbon materials prepared in Example 2, Comparative Example 1 and Comparative Example 2: Figure 3 The N2 adsorption-desorption isotherms and pore size distribution curves of the fungus-based porous biomass carbon materials prepared in Example 2(a)(b), Comparative Example 1(c)(d) and Comparative Example 2(e)(f) were compared. Figure 3 (a) and 3 (b) show the N2 adsorption-desorption isotherm and pore size distribution curve of the wood ear-based porous biomass carbon material prepared in Example 2. The morphological characteristics of the N2 adsorption-desorption isotherm are characterized by a rapid increase in adsorption amount at a lower relative pressure and saturation after reaching a certain relative pressure, which is consistent with the type I adsorption isotherm characteristics in the IUPAC classification. The specific surface area of ​​the BF-Z material is about 1010.043m 2 / g, and the pore volume is about 0.531cm 3 / g. Compared to: Figure 3 (c) and 3 (d) N2 adsorption-desorption isotherms and pore size distribution curves of the fungus-based porous biomass carbon material prepared in Comparative Example 1. The specific surface area of ​​the fungus-based porous biomass carbon (BF) is about 197.747 m 2 / g, and the pore volume is about 0.077cm 3 / g, which is significantly lower than the specific surface area and pore volume of the fungus-based porous biomass carbon material (BF-Z) prepared in Example 2; Figure 3 (e) and 3 (f) show the N2 adsorption-desorption isotherm and pore size distribution curve of the fungus-based porous biomass carbon material prepared in Comparative Example 2. The specific surface area of ​​the fungus-based porous biomass carbon is only 7.688 m 2 / g, and the pore volume is only 0.002cm 3 / g. This data clarifies the key role of the secondary cleaning step in improving the specific surface area and pore volume of the sample. The introduction of the activator zinc chloride promotes the effective emission of gas products (such as CO, CO2, etc.) during the high-temperature carbonization reaction, thereby generating a large number of nano-scale pores inside the material. However, if the remaining ZnCl2 and the reaction by-product ZnO are not removed in time, they will hinder the complete formation and expansion of the pores. Therefore, the secondary cleaning step significantly optimizes the development of the pore structure by removing the above-mentioned impurities, and the drying step after the secondary cleaning effectively promotes the improvement of porous properties. It can be seen that this process link is of indispensable importance to the pore construction and performance of the final material. Overall, the use of the activator zinc chloride combined with the secondary cleaning step significantly improved the specific surface area and pore volume of the wood ear-based porous biomass carbon, thereby providing more adsorption sites for the sample and significantly improving its adsorption performance.

[0038] As can be seen from the above, the method for preparing the wood ear-based porous biomass carbon material of the present invention has the following advantages: 1. Raw material selection: Using wood ear mushrooms as raw material, we use a simplified pretreatment process to remove impurities and dry them to obtain suitable biomass materials. Compared with traditional freeze-drying methods, this method is not only simpler to operate but also more energy-efficient.

[0039] 2. Use of Activator: Zinc chloride (ZnCl2) is selected as the activator, mixed with the wood ear-based raw materials, and then properly carbonized. Zinc chloride plays a key role in the activation process, effectively promoting the porosity of the material.

[0040] 3. Activation process: This involves a pyrolysis reaction at a relatively low temperature. During this process, temperature and time are strictly controlled to ensure optimal pore structure formation. Unlike previous activation processes that required argon protection, this method uses only standard-purity nitrogen as the shielding gas, significantly reducing costs.

[0041] 4. Cleaning: After the reaction is complete, a secondary cleaning process is performed to remove residual activator and byproducts, ensuring the integrity of the pore structure and the high purity of the final product. Compared to traditional acid-washing methods, this study uses deionized water and anhydrous ethanol for cleaning, further improving environmental friendliness. No activator residue remains in the final carbon material, ensuring the purity of the material. The activator can also be recovered and re-extracted, improving the sustainability of the process while effectively reducing resource waste.

[0042] In addition, the use of activator zinc chloride in combination with the secondary washing step significantly improves the specific surface area and pore volume of the auricularia-based porous biomass carbon, thereby providing more adsorption sites for the sample and significantly improving its adsorption performance. In this process, the key role of the secondary washing step is particularly emphasized. The introduction of the activator zinc chloride promotes the effective discharge of gas products (such as CO, CO2, etc.) in the high-temperature carbonization reaction, thereby generating a large number of nanoscale pores inside the material. However, if the residues such as the remaining ZnCl2 and the reaction byproduct ZnO are not removed in time, they will hinder the complete formation and expansion of the pores. Therefore, the secondary washing step removes the above impurities, and the drying step after secondary washing significantly optimizes the development of the pore structure, effectively promoting the improvement of the porous performance. As can be seen, this process step is indispensable for the pore construction and performance of the final material. Compared with the auricularia-based porous biomass carbon material that does not use zinc chloride as an activator but is subjected to secondary washing, the specific surface area and pore volume are increased by 4.1 times and 5.9 times, respectively. Compared with the auricularia-based porous biomass carbon material that uses zinc chloride as an activator but is not subjected to secondary washing, the specific surface area and pore volume are increased by 130.4 times and 264.5 times, respectively. This improvement provides more adsorption sites for the material, thereby significantly enhancing its adsorption performance, especially in adsorbing pollutants such as iodine vapor.

[0043] 5. Post-processing: After secondary washing, the prepared auricularia-based porous biomass carbon material exhibits excellent chemical stability through appropriate drying treatment. Its porous structure does not show obvious damage or collapse during long-term use, ensuring the stability of the material in multiple adsorption and desorption cycles. In the cycle experiment of multiple iodine vapor adsorption-desorption, the adsorption performance of the auricularia-based porous biomass carbon material almost does not decline, indicating that it has significant reuse ability in practical application. This feature makes it particularly suitable for high-frequency, long-term pollutant adsorption processes, which can significantly reduce the replacement frequency and use cost of the material, thereby improving its economic benefit and practical application value.

[0044] 6. Product characteristics: The final synthesized auricularia-based porous biomass carbon material has a clear void structure and is widely used for pollutant adsorption, especially in the field of iodine vapor adsorption, etc. The auricularia-based porous biomass carbon material prepared in Example 2 exhibits extremely high adsorption capacity in the iodine vapor adsorption experiment, reaching 2129-2893 mg / g, indicating that the material has excellent adsorption capacity. Through comparative tests by Fourier transform infrared (FT-IR), Raman spectroscopy (Raman), and thermogravimetric analysis (TGA) techniques, it is further confirmed that there is a synergistic effect of physical adsorption and chemical adsorption during the adsorption process, making the material have wide application potential in environmental governance and gas adsorption fields.

[0045] In summary, by employing a rational activator selection, precise temperature control strategy, and a secondary cleaning step, a porous wood ear-based biomass carbon material was successfully synthesized. The prepared porous carbon material not only exhibits a well-defined and regular pore structure but also demonstrates excellent iodine vapor adsorption performance, fully validating the remarkable effectiveness and advantages of this method in the synthesis of highly efficient adsorption materials. This research achievement provides important technical pathways and theoretical support for the further development of materials with excellent adsorption capacity.

[0046] Note that the above are only preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the concept of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for preparing a fungus-based porous biomass carbon material, characterized in that: include: S1. Preliminary cleaning of the fungus, followed by drying at 50-70°C for 2 hours; S2. The pretreated fungus is mixed with an activator and carbonized at a temperature of 600 to 900°C for 1 to 3 hours under nitrogen protection; S3. The product obtained in step S2 is filtered and washed with anhydrous ethanol and deionized water in sequence, and then dried at a temperature of 50 to 70° C. to a constant weight to obtain a fungus-based porous biomass carbon material.

2. The method for preparing a fungus-based porous biomass carbon material according to claim 1, wherein: In the step S1, the preliminary cleaning of the fungus includes: soaking the fungus in deionized water and anhydrous ethanol in sequence, and performing ultrasonic cleaning.

3. The method for preparing a fungus-based porous biomass carbon material according to claim 1 or 2, characterized in that: In step S1, preliminary cleaning of the fungus includes: Use deionized water to rinse the fungus for the first time; Soak the fungus in deionized water, ultrasonically clean it for 5 to 20 minutes, and rinse it twice with deionized water; Soak the fungus in anhydrous ethanol, clean it with ultrasonic cleaning for 1 to 3 hours, and rinse it again with deionized water.

4. The method for preparing a fungus-based porous biomass carbon material according to claim 1, wherein: In step S2, the activator is zinc chloride.

5. The method for preparing a fungus-based porous biomass carbon material according to claim 4, characterized in that: In the step S2, the pretreatment is: grinding the fungus and the activator into powder respectively.

6. The method for preparing a fungus-based porous biomass carbon material according to claim 5, characterized in that: In the step S2, the mixing mass ratio of the fungus to the activator is 1:1-3.

7. The method for preparing a fungus-based porous biomass carbon material according to claim 6, characterized in that: In the step S2, under nitrogen protection, the temperature is raised to 600-900° C. at a heating rate of 3-8° C. / min.

8. The method for preparing a fungus-based porous biomass carbon material according to claim 1, characterized in that: In the step S3: The product obtained in step S2 is washed 1 to 3 times by suction with anhydrous ethanol; The product was filtered and washed with deionized water until the pH value was 7.

9. The method for preparing a fungus-based porous biomass carbon material according to claim 1, characterized in that: In step S3, the drying time is 12 hours.

10. A fungus-based porous biomass carbon material prepared by the preparation method according to any one of claims 1 to 9.

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