A waste mask biochar bag, a composite biochar and bio-oil and a preparation method

Abstract

The application provides a waste mask biochar bag, a composite biochar and bio-oil and a preparation method, which comprises the following steps: after a waste disposable medical mask is recycled, the waste mask is subjected to disinfection treatment, and a filter layer and an inner layer of the disinfected waste mask are made into a tea bag type; biochar prepared by taking biomass as raw material is put into the tea bag type and is sealed, so that a waste mask biochar bag is obtained; the waste mask biochar bag is put into an organic solution for adsorption; the waste mask biochar bag after the organic solution is adsorbed is dried to constant weight; the dried waste mask biochar bag is placed in a fixed bed reactor, is slowly co-pyrolyzed under the protection of nitrogen at 300 DEG C to 550 DEG C, and is heated, so that a composite biochar and bio-oil are obtained. The application can realize resource utilization and closed loop recycling of the waste mask, can reduce the recycling cost of the biochar, and can obtain an efficient adsorbent, i.e., the composite biochar, and high-quality bio-oil.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of sewage treatment, and more particularly relates to a waste mask biochar package, a composite biochar and bio-oil and a preparation method. BACKGROUND

[0002] Adsorption is a method of using porous solids (adsorbents) to adsorb one or more pollutants (adsorbates) in wastewater to recover or remove these pollutants, thereby purifying the wastewater. Activated carbon is the most commonly used adsorbent, which is usually derived from coal or biomass pyrolysis. Although activated carbon made from coal has a large supply and a low price, coal as a primary energy source is gradually decreasing in global reserves.

[0003] Biochar is a carbon-rich product generated by the pyrolysis of biomass under anaerobic conditions. It has a low degree of carbonization, a large pore structure, and a surface rich in O- and N-containing functional groups that can interact with pollutants. Therefore, biochar is a good adsorbent for heavy metals and organic pollutants in water bodies and soils. However, if powdered biochar is directly applied to wastewater treatment, there are problems such as high biochar recovery and processing costs.

[0004] Environmental pollution has become a global concern. The removal of heavy metals and organic pollutants from environmental media is a task that must be addressed to ensure soil safety and water ecological safety. Adsorption is a relatively simple and efficient method for removing environmental pollutants, but existing adsorbents still cannot meet the high efficiency of removing and recovering pollutants from environmental media.

[0005] At the same time, due to the sharp increase in the use of masks, if there is no proper waste management method and utilization strategy, discarded masks will pollute the environment. SUMMARY

[0006] To solve the above technical problems, one of the purposes of one embodiment of the present application is to provide a preparation method of a waste mask biochar package, a composite biochar and bio-oil, which can realize the resource utilization and closed-loop recovery of waste masks, reduce the recovery cost of biochar, and obtain efficient adsorbent-composite biochar and high-quality bio-oil.

[0007] One of the purposes of one embodiment of the present application is to provide a waste mask biochar package prepared according to the preparation method of a waste mask biochar package, a composite biochar and bio-oil.

[0008] One of the purposes of one embodiment of the present application is to provide a composite biochar prepared according to the preparation method of a waste mask biochar package, a composite biochar and bio-oil.

[0009] One of the objects of one embodiment of the present application is to provide a low-nitrogen low-oxygen rich hydrocarbon bio-oil, which is prepared according to the preparation method of the waste mask biochar bag, composite biochar and bio-oil.

[0010] Note that the description of these objects does not hinder the existence of other objects. One embodiment of the present application does not need to achieve all the above-mentioned objects. The objects other than the above-mentioned objects can be extracted from the description of the specification, drawings and claims.

[0011] The present application achieves the above technical object through the following technical means.

[0012] The method of the present application comprises the following steps: pretreatment of waste masks; preparation of waste mask biochar bag; adsorption of waste mask biochar bag; drying of waste mask biochar bag; low-temperature pyrolysis of waste mask biochar bag. First, the waste masks are isolated, preferably for ten days, and subjected to ultraviolet disinfection, and then the inner layer and filter layer of the waste masks are made into a tea bag style; then the biochar is placed in the prepared tea bag style to prepare a waste mask biochar bag; then the mask biochar bag is placed in an organic solution for adsorption; finally, the mask biochar bag waste is dried in an oven, and then subjected to low-temperature slow co-pyrolysis at 300-550 DEG C, and then taken out after natural cooling to room temperature, to obtain high-quality composite biochar and bio-oil. The preparation method can realize the resource utilization and closed-loop recycling of waste masks, reduce the recycling cost of biochar, and obtain high-quality bio-oil and efficient adsorbent-composite biochar without activation and acid washing.

[0013] The use of the waste mask biochar bag not only reduces the cost of subsequent filtration and centrifugation, but also avoids secondary pollution of the environment. In addition, the waste mask biochar bag after pyrolysis can obtain high-quality bio-oil on the one hand, and can prepare more efficient adsorbents on the other hand.

[0014] The present application provides a preparation method of a waste mask biochar bag, composite biochar and bio-oil, which can better recycle waste masks, reduce environmental burden, realize closed-loop recycling of disposable masks, better recycle powdered biochar in organic sewage treatment, and reduce recycling cost.

[0015] A preparation method of a waste mask biochar bag, composite biochar and bio-oil, comprising the following steps:

[0016] Step S1, waste mask pretreatment: after recycling, the waste disposable medical mask is subjected to disinfection treatment, and the filter layer and inner layer of the disinfected waste mask are made into a tea bag style;

[0017] Step S2, waste mask biochar bag preparation: the biochar prepared by biomass as raw material is put into the tea bag type and sealed, and the waste mask biochar bag is obtained.

[0018] Step S3, waste mask biochar bag adsorption: the waste mask biochar bag is put into the organic solution for adsorption.

[0019] Step S4, waste mask biochar bag drying: the waste mask biochar bag after adsorbing the organic solution is dried to constant weight in an oven.

[0020] Step S5, waste mask biochar bag low-temperature pyrolysis: the dried waste mask biochar bag is placed in a fixed bed reactor, and under the protection of nitrogen, it is slowly co-pyrolyzed by rising to 300-550℃, and then naturally cooled to room temperature under the protection of nitrogen, and then taken out, to obtain composite biochar and bio-oil.

[0021] In the above scheme, the step S1 is specifically: after the waste disposable medical mask is recovered, ultraviolet sterilization is carried out, the sterilized mask is disassembled, the filter layer and the inner layer are overlapped, and the three edges are sealed to make a tea bag type.

[0022] In the above scheme, the biochar in step S2 is prepared by combining one or more of enteromorpha, chlorella, pomelo peel, straw, coffee grounds, sawdust and peanut shells, which has the advantages of low cost and sustainability, and can protect primary energy represented by coal.

[0023] In the above scheme, in step S2, the weight-to-volume ratio of biochar to organic solution in step S2 is 1:100, and the concentration of organic solution is 50-400 mg / L.

[0024] In the above scheme, in step S3, adsorption is carried out under magnetic stirring at 150 rpm and the temperature is 30℃.

[0025] In the above scheme, the waste mask biochar bag after adsorbing the organic solution is placed in a 105℃ oven to dry to constant weight.

[0026] In the above scheme, in step S5, under the protection of nitrogen, the temperature is raised to 300-550℃ at a rate of 10℃ / min, the slow co-pyrolysis nitrogen flow rate is 150 mL / min, and the time is 30 min.

[0027] A waste mask biochar bag is prepared according to the preparation method of the waste mask biochar bag, composite biochar and bio-oil.

[0028] A composite biochar is prepared according to the preparation method of the waste mask biochar bag, composite biochar and bio-oil.

[0029] A biological oil is prepared according to the preparation method of the waste mask biochar bag, the composite biochar and the biological oil.

[0030] Compared with the prior art, the present application has the following beneficial effects:

[0031] The present application can make full use of waste masks, realize resource utilization of waste masks, reduce microplastic pollution caused by waste masks to some extent, reduce the influence on the environment, and provide a solution for the treatment of a large number of waste masks.

[0032] The mask biochar bag of the present application uses biochar to adsorb organic sewage, which can effectively improve the efficiency of organic sewage treatment, greatly shorten the wastewater treatment time, and effectively reduce the recovery cost of powdered biochar.

[0033] For the repair of open water bodies, the application of columnar filtration shows serious limitations, and the present application encapsulates the adsorbent biochar in a tea bag-shaped mask made of waste masks, which can be directly thrown into water to realize adsorption and is more suitable and has a wider application range.

[0034] In the low-temperature pyrolysis reaction, the mutual synergistic effect between the plastic components in the mask and the biochar bag adsorbed with organic solution in the waste mask biochar bag is improved compared with the pyrolysis using biomass as raw material alone, and the quality of the bio-oil is improved compared with the use of recyclable waste masks alone, and the biochar production is improved and has good adsorption performance; at the same time, compared with the biomass pyrolysis alone, the by-product composite biochar prepared by the present application, on the one hand, the temperature required for pyrolysis is lower, which can reduce energy consumption; on the other hand, in the post-processing aspect, the composite biochar does not need to go through any activation process, nor does it need to go through any pickling and washing process, which greatly reduces the cost of producing high-efficiency adsorbent-biochar.

[0035] The internal circulation generated by the present application can consume pollutants inside, and the by-products high-quality bio-oil and biochar generated in the process can be used as new energy for continuous use, applied to fuel and water treatment, so as to realize the recycling of waste and achieve the recycling of energy.

[0036] Note that the description of these effects does not hinder the existence of other effects. One embodiment of the present application does not necessarily have all the above effects. Effects other than the above can be easily seen and extracted from the description, drawings, claims, etc.

[0037] The description of these effects does not hinder the existence of other effects. One embodiment of the present application does not necessarily have all the above effects. Effects other than the above can be easily seen and extracted from the description, drawings, claims, etc. BRIEF DESCRIPTION OF DRAWINGS

[0038] The above and other objects, features and advantages of the present application will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which:

[0039] Figure 1 A suggested flow chart of the preparation method according to one embodiment of the present application is shown.

[0040] Figure 2 GC-MS analysis of bio-oil obtained from one embodiment of the present application, wherein Figure 2 (a) is GC-MS of bio-oil from pyrolysis of waste mask carbon package at 300°C, Figure 2 (b) is GC-MS of bio-oil from pyrolysis of waste mask carbon package at 400°C, Figure 2 (c) is GC-MS of bio-oil from pyrolysis of waste mask carbon package at 550°C, Figure 2 (d) is GC-MS of bio-oil from pyrolysis of biochar waste at 550°C.

[0041] Figure 3 Adsorption kinetics analysis graph of composite biochar at different pyrolysis temperatures of 400mg / L MB solution according to one embodiment of the present application.

[0042] Figure 4 Removal rate analysis graph of Enteromorpha biochar and composite biochar according to one embodiment of the present application (Note: AC-Enteromorpha biochar; MAC-composite biochar, pyrolysis temperature-300°C).

[0043] Figure 5 Adsorption capacity analysis graph of Enteromorpha biochar and composite biochar according to one embodiment of the present application (Note: AC-Enteromorpha biochar; MAC-composite biochar, pyrolysis temperature-300°C).

[0044] Figure 6 Adsorption kinetics analysis graph of composite biochar at different pyrolysis temperatures of 400mg / L TC solution according to one embodiment of the present application. DETAILED DESCRIPTION

[0045] The embodiments described below are exemplary and are intended to be illustrative of the present application and are not to be construed as limiting thereof.

[0046] Figure 1 A preferred embodiment of the preparation method of the waste mask biochar package, composite biochar and bio-oil is shown, and the preparation method of the waste mask biochar package, composite biochar and bio-oil comprises the following steps:

[0047] Step S1, waste mask pretreatment: after recycling, disinfecting and filtering the inner layer of the waste disposable medical mask, the waste mask is made into a tea bag style;

[0048] Step S2, waste mask biochar bag preparation: a certain amount of biochar prepared by biomass as raw material is put into the tea bag style and sealed, and a waste mask biochar bag is obtained;

[0049] Step S3, waste mask biochar bag adsorption: the waste mask biochar bag is placed in a certain concentration of organic solution for adsorption;

[0050] Step S4, waste mask biochar bag drying: the waste mask biochar bag after adsorbing the organic solution is dried to constant weight;

[0051] Step S5, waste mask biochar bag low-temperature pyrolysis: the dried waste mask biochar bag is placed in a fixed bed reactor, and under the protection of nitrogen, it is slowly co-pyrolyzed to 300-550°C, and then naturally cooled to room temperature under the protection of nitrogen, and then taken out, to obtain composite biochar and bio-oil.

[0052] Step S6, waste mask biochar bag adsorption: the composite biochar is placed in a certain concentration of organic solution for adsorption.

[0053] Preferably, the step S1 is specifically: after the waste disposable medical mask is recovered, it is isolated for ten days, ultraviolet sterilization is performed, the sterilized mask is disassembled, the filter layer and the inner layer are overlapped, the three edges are sealed, and a tea bag style is made. Preferably, the tea bag style is 90mm long and 40mm wide.

[0054] Preferably, the biomass in step S2 is one or a combination of Enteromorpha, Chlorella, pomelo peel, straw, coffee grounds, sawdust, and peanut shells.

[0055] Preferably, in step S2, 1g of biochar prepared by biomass as raw material is put into the tea bag style, the concentration of the organic solution is 50-400mg / L, and the volume is 1000mL.

[0056] Preferably, in step S3, the adsorption is carried out under magnetic stirring at 150rpm and the temperature is 30°C.

[0057] Preferably, in step S3, the biochar used is 1g, the concentration of the organic solution is 50-400mg / L, and the volume is 1000mL.

[0058] Preferably, in step S4, the waste mask biochar bag after adsorbing the organic solution is placed in a 105°C oven and dried to constant weight.

[0059] Preferably, in step S5, under nitrogen protection, the temperature is increased to 300℃~550℃ at a heating rate of 10℃ / min, the slow co-pyrolysis flow rate is 150mL / min, and the time is 30min. Afterwards, it is naturally cooled to room temperature under nitrogen protection and then removed to obtain composite biochar. Preferably, in step S5, the slow co-pyrolysis is carried out in a continuous fixed-bed pyrolysis reactor.

[0060] Preferably, the biochar used in step S6 is 0.1g, the concentration of the organic solution is 400-3000mg / L, and the volume is 100mL.

[0061] Composite biochar adsorption performance test:

[0062] The adsorption performance of the dried composite biochar was tested. 0.1 g of the composite biochar was placed in 100 mL of an organic solution with a concentration of 400–3000 mg / L, and adsorption was carried out in a shaker. The adsorption performance test of the composite biochar was conducted in a constant temperature shaker at 30°C with a shaking rate of 150 rpm. Preferably, the amount of biochar used in the adsorption performance test was 0.1 g, and the concentration of the methylene blue solution was 400–3000 mg / L, with a volume of 100 mL.

[0063] A type of waste mask biochar pack is prepared according to the preparation method of the waste mask biochar pack, composite biochar and bio-oil.

[0064] A composite biochar is prepared according to the method for preparing waste mask biochar packs, composite biochar, and bio-oil.

[0065] A bio-oil is prepared according to the method for preparing waste mask biochar packs, composite biochar, and bio-oil.

[0066] This invention, during low-temperature pyrolysis, demonstrates a synergistic effect between the plastic component of discarded masks and the biochar pack containing adsorbed organic solutions. Compared to using biomass alone as a raw material for pyrolysis, the quality of the bio-oil is improved, and the biochar yield is increased with better adsorption performance compared to using recyclable discarded masks alone. Plastic is a hydrogen-rich raw material, containing 8-14% hydrogen. The thermal decomposition of plastic produces hydrogen-rich gas. Since masks contain plastic components, their pyrolysis promotes the formation of carbon pores. Channel connectivity and pore size distribution typically affect the adsorption efficiency and electron transfer rate of porous carbon. Micropores provide numerous active sites and charge storage, mesopores facilitate mass diffusion and ion transport, while the formation of macropores may reduce active sites. Polypropylene plastic, as an additive, enhances adsorption performance. Since the main component of discarded masks is polypropylene, the synergistic effect between the discarded masks and biochar during pyrolysis promotes biochar pore formation and improves its adsorption performance. On the other hand, biochar, as a carbon-based catalyst, plays a certain catalytic role in the pyrolysis of masks, further improving the quality of their bio-oil. Meanwhile, compared to the pyrolysis of biomass alone, the byproduct—composite biochar—prepared by this invention requires a lower pyrolysis temperature, reducing energy loss. Furthermore, in terms of post-processing, the composite biochar does not require any activation, acid washing, or water washing processes, significantly reducing the cost of producing high-efficiency adsorbent biochar.

[0067] In this invention, nitrogen-containing and sulfur-containing compounds generated during the pyrolysis of biomass pollute the environment. Meanwhile, the waste generated after biochar adsorbs organic wastewater contains large amounts of N, S, and P elements. Disposable masks are made of polypropylene and do not contain N or S elements, but their pyrolysis requires high temperatures and long processing times. When these two are used in combination, on the one hand, the content of nitrogen-containing and sulfur-containing compounds is significantly reduced, thus reducing environmental pollution; on the other hand, energy waste is also reduced. Furthermore, the internal circulation generated by this invention allows pollutants to be consumed internally, while the high-quality bio-oil and biochar produced during the process can be used as new energy sources for fuel and water treatment, giving waste new utilization value and achieving energy recycling.

[0068] Example 1

[0069] A method for preparing biochar packets from discarded face masks, composite biochar, and bio-oil includes the following steps:

[0070] (1) Pre-treatment of discarded masks: After recycling, the discarded masks are isolated for ten days and then sterilized with ultraviolet light. The filter layer and inner layer of the sterilized masks are made into a tea bag shape with a length of 90mm and a width of 40mm.

[0071] (2) Preparation of biochar packs for discarded masks: 1g of biochar prepared from seaweed is placed into the tea bag pattern obtained in step (1) to obtain biochar packs for masks;

[0072] (3) Adsorption of biochar packs from discarded masks: The biochar packs from the masks are placed in a 1000 mL solution of methylene blue with a concentration of 50-400 mg / L for adsorption until the water becomes transparent.

[0073] (4) Drying of waste mask biochar packs: Place the adsorbed mask biochar pack waste in a glass dish and dry it in a 105℃ oven until constant weight;

[0074] (5) Low-temperature pyrolysis of waste mask biochar packs: Under nitrogen protection, the temperature is raised to 300℃ at a rate of 10℃ / min and slowly pyrolyzed for 30min. After that, the packs are naturally cooled to room temperature under nitrogen protection and then taken out to obtain bio-oil and composite biochar.

[0075] Experimental results show that under pyrolysis conditions at 300℃, the... Figure 2 (a) It can be seen that the bio-oil produced by the pyrolysis of biochar packs from discarded masks has a hydrocarbon content of 64.33% and a nitrogen content of 1.4%, which is 28.77% lower than the nitrogen content of biochar waste pyrolysis alone.

[0076] To investigate the adsorption performance of biochar packs from discarded face masks and the application of composite biochar, the following experiments were conducted:

[0077] Experiment 1:

[0078] 1g of biochar was placed into the tea bag sample obtained in step (1) to obtain the biochar mask pack. The biochar mask pack was then placed in a 400mg / L, 1000mL methylene blue solution for adsorption until the water became transparent.

[0079] Experimental results show that the methylene blue solution became completely transparent in the water after 5 minutes. The removal rate was 99.98%. Compared to adsorption by 1g of biochar alone, the removal rate increased by 22.78% within the same time period.

[0080] To investigate the adsorption performance of composite biochar, the following experiments were conducted:

[0081] Experiment 2: 0.1g of composite biochar was placed in a methylene blue solution with an initial concentration of 400mg / L for adsorption. The composite biochar was placed in 100mL of methylene blue solution with an initial concentration of 400mg / L, maintained at pH at room temperature, for adsorption. The adsorption process took place in a constant-temperature shaker at 30℃ and a shaking rate of 150rpm. Shaking continued until the water became transparent. 1mL of methylene blue solution was taken to test the absorbance, and the removal rate and adsorption capacity were calculated.

[0082] Experiment 3: 0.1g of composite biochar was placed in a methylene blue solution with an initial concentration of 500–3000 mg / L for adsorption. The composite biochar was placed in 100mL of methylene blue solution with an initial concentration of 500–3000 mg / L, maintained at pH at room temperature, for adsorption. The adsorption process took place in a constant-temperature shaker at 30℃, with the shaking speed maintained at 150 rpm. Shaking continued until the water became transparent. 1mL of methylene blue solution was taken to test the absorbance, and the removal rate and adsorption capacity were calculated.

[0083] Experimental results show that, as shown in Figure (3), the methylene blue solution became completely transparent after 5 minutes. The removal rate of the composite biochar was 98.05%. Compared with the adsorption of 0.1g of original biochar alone, the removal rate increased by 55.01% in the same time period. As shown in Figure (4), when the concentration was 500-3000mg / L, the removal rate remained at 90.83%-52.10%, and the adsorption capacity remained at 454.15mg / g-1562.96mg / g. It can be seen that the adsorption performance of the composite biochar was improved compared with that of the original biochar. This invention not only used waste masks and waste biomass, but also used the waste of the mask carbon pack in the subsequent cycle. Moreover, the adsorption performance of the by-product of the pyrolysis of this waste - composite biochar - was even better than that of the original biochar. In this embodiment, the yield of the pyrolysis oil of the mask and biochar was 76%, and the yield of the pyrolysis oil of biochar alone was 9.4%, which shows that the bio-oil production was improved.

[0084] Example 2

[0085] A method for preparing biochar packets from discarded face masks, composite biochar, and bio-oil includes the following steps:

[0086] (1) Pre-treatment of discarded masks: After recycling, the discarded masks are isolated for ten days and then sterilized with ultraviolet light. The filter layer and inner layer of the sterilized masks are made into a tea bag shape with a length of 90mm and a width of 40mm.

[0087] (2) Preparation of biochar packs for discarded masks: 1g of biochar prepared from seaweed is placed into the tea bag pattern obtained in step (1) to obtain biochar packs for masks;

[0088] (3) Adsorption of biochar packs from discarded masks: The biochar packs from the masks are placed in a 1000 mL solution of methylene blue with a concentration of 50-400 mg / L for adsorption until the water becomes transparent.

[0089] (4) Drying of waste biochar packs from discarded masks: Place the adsorbed biochar packs from the masks in a glass dish and dry them in an oven at 105°C until constant weight.

[0090] (5) Low-temperature pyrolysis of waste biochar bags from discarded masks: Under nitrogen protection, the temperature is raised to 400℃ at a rate of 10℃ / min and slowly pyrolyzed for 30min. After that, the bags are naturally cooled to room temperature under nitrogen protection and then removed to obtain composite biochar.

[0091] Experimental results show that under pyrolysis conditions at 400℃, the... Figure 2 (b) It can be seen that the bio-oil produced by the pyrolysis of biochar packs from discarded masks has a hydrocarbon content of 55.31% and a nitrogen content of 2.5%, which is 28.57% lower than that of biochar waste pyrolysis alone.

[0092] To investigate the adsorption performance of biochar packs from discarded face masks and the application of composite biochar, the following experiments were conducted:

[0093] Experiment 1:

[0094] 1g of biochar was placed into the tea bag sample obtained in step (1) to obtain the biochar pack for the mask. The biochar pack was then placed in a 400mg / L, 1000mL methylene blue solution for adsorption until the water became transparent.

[0095] Experimental results show that, obviously, the methylene blue solution became completely transparent in the water after 100 minutes. The removal rate was 95.35%, which is 22.28% higher than that of 1g of biochar adsorption alone within the same time period.

[0096] To investigate the adsorption performance of composite biochar, the following experiments were conducted:

[0097] Experiment 2: 0.1g of composite biochar was placed in a methylene blue solution with an initial concentration of 400mg / L for adsorption. The composite biochar was placed in 100mL of methylene blue solution with an initial concentration of 400mg / L, maintained at pH at room temperature, for adsorption. The adsorption process took place in a constant-temperature shaker at 30℃ and a shaking rate of 150rpm. Shaking continued until the water became transparent. 1mL of methylene blue solution was taken to test the absorbance, and the removal rate and adsorption capacity were calculated.

[0098] The experimental results show that, obviously, after 5 minutes, as shown in Figure (3), the methylene blue solution in the water became completely transparent. The removal rate of the composite biochar was 95.05%. Compared with the adsorption of 0.1g of raw biochar alone, the removal rate increased by 45.76% in the same time period.

[0099] Example 3

[0100] A method for preparing a biochar-integrated waste mask biochar pack for wastewater adsorption includes the following steps:

[0101] (1) Pre-treatment of discarded masks: After recycling, the discarded masks are isolated for ten days and then sterilized with ultraviolet light. The filter layer and inner layer of the sterilized masks are made into a tea bag shape with a length of 90mm and a width of 40mm.

[0102] (2) Preparation of biochar packs for discarded masks: 1g of biochar prepared from seaweed is placed into the tea bag pattern obtained in step (1) to obtain biochar packs for masks;

[0103] (3) Adsorption of biochar packs from discarded masks: The biochar packs from the masks are placed in a 1000 mL solution of methylene blue with a concentration of 50-400 mg / L for adsorption until the water becomes transparent.

[0104] (4) Drying of waste biochar packs from discarded masks: Place the adsorbed biochar packs from the masks in a glass dish and dry them in an oven at 105°C until constant weight.

[0105] (5) Low-temperature pyrolysis of waste biochar bags from discarded masks: Under nitrogen protection, the temperature is raised to 550°C at a rate of 10°C / min and slowly pyrolyzed for 30 minutes. After that, the bags are naturally cooled to room temperature under nitrogen protection and then removed to obtain composite biochar.

[0106] Experimental results show that under pyrolysis conditions at 550℃, the... Figure 2 (c) and Figure 2(d) It can be seen that the bio-oil produced by the pyrolysis of biochar waste from masks has a hydrocarbon content of 50.69% and a nitrogen content of 2.88%, which is 28.19% lower than that produced by the pyrolysis of biochar waste alone.

[0107] To investigate the adsorption performance of biochar packs in face masks and the application of composite biochar, the following experiments were conducted:

[0108] Experiment 1:

[0109] 1g of biochar was placed into the tea bag sample obtained in step (1) to obtain the biochar pack for the mask. The biochar pack was then placed in a 400mg / L, 1000mL methylene blue solution for adsorption until the water became transparent.

[0110] Experimental results show that the methylene blue solution became completely transparent in the water after 100 minutes. The removal rate was 94.14%. Compared to the adsorption of 1g of raw biochar alone, the removal rate increased by 21.26% within the same time period.

[0111] To investigate the adsorption performance of composite biochar, the following experiments were conducted:

[0112] Experiment 2: 0.1g of composite biochar was placed in a methylene blue solution with an initial concentration of 400mg / L for adsorption. The composite biochar was placed in 100mL of methylene blue solution with an initial concentration of 400mg / L, maintained at pH at room temperature, for adsorption. The adsorption process took place in a constant-temperature shaker at 30℃ and a shaking rate of 150rpm. Shaking continued until the water became transparent. 1mL of methylene blue solution was taken to test the absorbance, and the removal rate and adsorption capacity were calculated.

[0113] Experimental results show that, as can be seen from Figure (3), the methylene blue solution became completely transparent after 5 minutes. The removal rate of the composite biochar was 94.39%. Compared with the adsorption of 0.1g of raw biochar alone, the removal rate increased by 55.01% in the same time period.

[0114] Example 4

[0115] A method for preparing a biochar-integrated waste mask biochar pack for wastewater adsorption includes the following steps:

[0116] (1) Mask pretreatment: After recycling the waste masks, isolate them for ten days and disinfect them with ultraviolet light. Make the filter layer and inner layer of the disinfected masks into a tea bag shape with a length of 90mm and a width of 40mm.

[0117] (2) Preparation of biochar packs for discarded masks: 1g of biochar prepared from seaweed is placed into the tea bag pattern obtained in step (1) to obtain biochar packs for masks;

[0118] (3) Adsorption of biochar packs from discarded masks: The biochar packs from the masks are placed in a tetracycline solution with a volume of 1000 mL and a concentration of 50-400 mg / L for adsorption until the solution reaches adsorption equilibrium.

[0119] (4) Drying of waste biochar packs from discarded masks: Place the adsorbed biochar packs from the masks in a glass dish and dry them in an oven at 105°C until constant weight.

[0120] (5) Low-temperature pyrolysis of waste mask biochar packs: The dried mask biochar packs are placed in a fixed bed reactor and heated to 300°C at a rate of 10°C / min under nitrogen protection. Then, they are slowly co-pyrolyzed for 30 min under nitrogen protection. After being naturally cooled to room temperature, they are taken out to obtain composite biochar.

[0121] To investigate the adsorption performance and applications of activated carbon packs in face masks, the following experiments were conducted:

[0122] Experiment 1:

[0123] 1g of biochar was placed into the tea bag sample obtained in step (1) to obtain the mask biochar pack. The mask biochar pack was then placed into a 400mg / L, 1000mL tetracycline solution for adsorption until the solution reached adsorption equilibrium.

[0124] Experimental results show that the tetracycline solution reached adsorption equilibrium after 150 minutes. After 5 minutes of adsorption, the removal rate was 52.16%. Compared to adsorption by 1g of raw biochar alone, the removal rate increased by 35.92% within the same timeframe.

[0125] To investigate the adsorption performance of composite biochar, the following experiments were conducted:

[0126] Experiment 2: 0.1 g of composite biochar was placed in a tetracycline solution with an initial concentration of 400 mg / L for adsorption. The composite biochar was placed in 100 mL of tetracycline solution with an initial concentration of 400 mg / L, maintained at pH at room temperature, for adsorption. The adsorption process took place in a constant-temperature shaker at 30℃ and a shaking rate of 150 rpm. Shaking continued until the water became transparent. 1 mL of the tetracycline solution was then taken to test the absorbance, and the removal rate and adsorption capacity were calculated.

[0127] Experimental results show that: obviously, after 5 minutes, the effect is... Figure 6The results show that the removal rate of the composite biochar was 62.93%. Compared with the adsorption of 0.1g of raw biochar alone, the removal rate increased by 46.69% in the same time period, and the adsorption equilibrium removal rate reached 88.22%.

[0128] Example 5

[0129] A method for preparing a biochar-integrated waste mask biochar pack for wastewater adsorption includes the following steps:

[0130] (1) Mask pretreatment: After recycling the waste masks, isolate them for ten days and disinfect them with ultraviolet light. Make the filter layer and inner layer of the disinfected masks into a tea bag shape with a length of 90mm and a width of 40mm.

[0131] (2) Preparation of biochar packs for discarded masks: 1g of biochar prepared from seaweed is placed into the tea bag pattern obtained in step (1) to obtain biochar packs for masks;

[0132] (3) Adsorption of biochar packs from discarded masks: The biochar packs from the masks are placed in a tetracycline solution with a volume of 1000 mL and a concentration of 50-400 mg / L for adsorption until the solution reaches adsorption equilibrium.

[0133] (4) Drying of waste biochar packs from discarded masks: Place the adsorbed biochar packs from the masks in a glass dish and dry them in an oven at 105°C until constant weight.

[0134] (5) Low-temperature pyrolysis of waste mask biochar packs: The dried mask biochar packs are placed in a fixed-bed reactor and heated to 400°C at a rate of 10°C / min under nitrogen protection. Then, they are slowly co-pyrolyzed for 30 minutes under nitrogen protection. After being naturally cooled to room temperature, they are taken out to obtain composite biochar.

[0135] To investigate the adsorption performance and applications of activated carbon packs in face masks, the following experiments were conducted:

[0136] Experiment 1:

[0137] 1g of biochar was placed into the tea bag sample obtained in step (1) to obtain the mask biochar pack. The mask biochar pack was then placed into a 400mg / L, 1000mL tetracycline solution for adsorption until the solution reached adsorption equilibrium.

[0138] Experimental results showed that the tetracycline solution reached adsorption equilibrium after 150 minutes. After 5 minutes of adsorption, the removal rate was 53.22%. Compared to adsorption by 1g of raw biochar alone, the removal rate increased by 36.98% within the same timeframe.

[0139] To investigate the adsorption performance of composite biochar, the following experiments were conducted:

[0140] Experiment 2: 0.1 g of composite biochar was placed in a tetracycline solution with an initial concentration of 400 mg / L for adsorption. The composite biochar was placed in 100 mL of tetracycline solution with an initial concentration of 400 mg / L, maintained at pH at room temperature, for adsorption. The adsorption process took place in a constant-temperature shaker at 30℃ and a shaking rate of 150 rpm. Shaking continued until the solution reached adsorption equilibrium. 1 mL of the tetracycline solution was taken to test the absorbance, and the removal rate and adsorption capacity were calculated.

[0141] Experimental results show that: obviously, after 5 minutes, the effect is... Figure 6 The results show that the removal rate of the composite biochar was 59.88%. Compared with the adsorption of 0.1g of biochar alone, the removal rate increased by 46.88% in the same time period, and the adsorption equilibrium removal rate reached 83.12%.

[0142] Example 6

[0143] A method for preparing a biochar-integrated waste mask biochar pack for wastewater adsorption includes the following steps:

[0144] (1) Mask pretreatment: After recycling the waste masks, isolate them for ten days and disinfect them with ultraviolet light. Make the filter layer and inner layer of the disinfected masks into a tea bag shape with a length of 90mm and a width of 40mm.

[0145] (2) Preparation of biochar packs for discarded masks: 1g of biochar prepared from seaweed is placed into the tea bag pattern obtained in step (1) to obtain biochar packs for masks;

[0146] (3) Adsorption of biochar packs from discarded masks: The biochar packs from the masks are placed in a tetracycline solution with a volume of 1000 mL and a concentration of 50-400 mg / L for adsorption until the solution reaches adsorption equilibrium.

[0147] (4) Drying of mask biochar pack waste: Place the adsorbed mask biochar pack in a glass dish and dry it in a 105℃ oven until constant weight;

[0148] (5) Low-temperature pyrolysis of waste biochar packs from masks: The dried biochar packs from masks are placed in a fixed-bed reactor and heated to 550°C at a rate of 10°C / min under nitrogen protection. Then, they are slowly co-pyrolyzed for 30 minutes under nitrogen protection. After being naturally cooled to room temperature, the composite biochar is obtained.

[0149] To investigate the adsorption performance and applications of activated carbon packs in face masks, the following experiments were conducted:

[0150] Experiment 1:

[0151] 1g of biochar was placed into the tea bag sample obtained in step (1) to obtain the mask biochar pack. The mask biochar pack was then placed into a 400mg / L, 1000mL tetracycline solution for adsorption until the solution reached adsorption equilibrium.

[0152] Experimental results showed that the tetracycline solution reached adsorption equilibrium after 150 min. After 5 min of adsorption, the removal rate was 54.11%. Compared to adsorption by 1 g of biochar alone, the removal rate increased by 37.87% within the same time frame.

[0153] To investigate the adsorption performance of composite biochar, the following experiments were conducted:

[0154] Experiment 2: 0.1 g of composite biochar was placed in a tetracycline solution with an initial concentration of 400 mg / L for adsorption. The composite biochar was placed in 100 mL of tetracycline solution with an initial concentration of 400 mg / L, maintained at pH at room temperature, for adsorption. The adsorption process took place in a constant-temperature shaker at 30℃ and a shaking rate of 150 rpm. Shaking continued until the solution reached adsorption equilibrium. 1 mL of the tetracycline solution was taken to test the absorbance, and the removal rate and adsorption capacity were calculated.

[0155] Experimental results show that: obviously, after 5 minutes, the effect is... Figure 6 It can be seen that tetracycline was removed until the solution reached adsorption equilibrium. The removal rate of the composite biochar was tested to be 58.23%. Compared with the adsorption of 0.1g of biochar alone, the removal rate was increased by 41.99% in the same time period, and the adsorption equilibrium removal rate could reach 83.19%.

[0156] GC-MS analysis of bio-oil and biochar waste, byproducts of pyrolysis of methylene blue-adsorbed biochar masks at 300℃, 400℃, and 500℃, respectively:

[0157] By utilizing the synergistic effect of discarded masks and biomass waste, the quality of bio-oil is significantly improved and its yield effectively increased, while simultaneously reducing the environmental pollution caused by masks. Through low-temperature pyrolysis, biochar bag waste can be converted into bio-oil in a short time under anaerobic conditions. The addition of discarded masks increases carbon and oxygen content and reduces nitrogen and sulfur content, resulting in higher quality bio-oil with less sulfur and nitrogen compound pollution. The bio-oil prepared by this invention contains only 1.4%–2.88% nitrogen compounds and no sulfur compounds. The advantages of this method are: bio-oil can be obtained through pyrolysis at a lower temperature in a fixed-bed reactor without damaging its quality; and the resulting composite biochar possesses excellent adsorption properties without any activation process.

[0158] This invention effectively solves the environmental pollution problem caused by the large-scale production and non-degradable nature of face masks, reducing their harm to the environment and humans. It can be used for centralized processing of disposable medical masks, thus having an environmentally friendly effect. During the low-temperature pyrolysis reaction, the synergistic effect between the mixed mask and biochar waste improves the quality of bio-oil compared to using biomass alone, and increases the bio-oil yield compared to using recyclable waste masks alone. Furthermore, compared to biomass pyrolysis alone, the byproduct—composite biochar—prepared by this invention requires a lower pyrolysis temperature, reducing energy loss. Additionally, the composite biochar does not require any activation or acid / water washing processes, significantly reducing the cost of biochar production. The waste biochar produced after the biochar adsorbs organic wastewater contains large amounts of elements such as nitrogen, sulfur, and phosphorus, which would harm the environment if directly stored there. Disposable masks are mainly composed of polypropylene, which does not contain such harmful substances. However, their pyrolysis requires high temperatures and long processing times. When combined with biochar as a catalyst, the pyrolysis of masks can produce oil. On one hand, the content of nitrogenous and sulfurous compounds produced is significantly reduced, minimizing environmental pollution. The bio-oil prepared by this invention contains only 1.4%–2.88% nitrogenous compounds and no sulfurous compounds, thus improving the quality and increasing the yield of bio-oil. On the other hand, the synergistic effect between the mask and biochar further enhances the adsorption performance of the byproduct—composite biochar—compared to the original biochar, resulting in increased biochar yield compared to mask pyrolysis alone. The adsorption performance of biochar is also improved compared to biochar pyrolysis alone. Simultaneously, energy waste is reduced. Furthermore, the internal circulation generated by this scheme allows pollutants to be consumed internally, while the high-quality bio-oil and biochar produced can be used as new energy sources for fuel and water treatment, giving waste new value and achieving energy reuse.

[0159] It should be understood that although this specification is described according to various embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0160] The detailed descriptions listed above are merely specific illustrations of feasible embodiments of the present invention and are not intended to limit the scope of protection of the present invention. All equivalent embodiments or modifications made without departing from the spirit of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing composite biochar and bio-oil, characterized in that, Includes the following steps: Step S1, Pre-treatment of discarded masks: After recycling, the discarded disposable medical masks are disinfected, and the filter layer and inner layer of the disinfected discarded masks are made into tea bag shapes; Step S2, Preparation of biochar packs from discarded masks: Place biochar prepared from biomass into the tea bag-shaped container and seal it to obtain biochar packs from discarded masks; Step S3, Adsorption of biochar from discarded masks: The biochar from the discarded masks is placed in an organic solution for adsorption; Step S4, Drying the waste mask biochar packs: Dry the waste mask biochar packs after adsorbing organic solutions to a constant weight; Step S5: Low-temperature pyrolysis of waste mask biochar packs: Place the dried waste mask biochar packs in a fixed-bed reactor and, under nitrogen protection, raise the temperature to 300℃~550℃ for slow co-pyrolysis. Afterward, remove the packs and allow them to cool naturally to room temperature under nitrogen protection to obtain composite biochar and bio-oil. The specific steps of step S1 are as follows: after recycling the discarded disposable medical masks, they are sterilized and disinfected with ultraviolet light. The disinfected masks are then removed, and the removed filter layer and inner layer are overlapped, sealed on three sides, and made into a tea bag shape. In step S5, under nitrogen protection, the temperature is raised to 300℃~550℃ at a heating rate of 10℃ / min, and then slowly co-pyrolyzed. The nitrogen flow rate is 150mL / min, and the time is 30min.

2. The method for preparing composite biochar and bio-oil according to claim 1, characterized in that, The biochar in step S2 is prepared from one or more of the following: seaweed, chlorella, grapefruit peel, straw, coffee grounds, sawdust, and peanut shells.

3. The method for preparing composite biochar and bio-oil according to claim 1, characterized in that, In step S3, adsorption is carried out under magnetic stirring at 150 rpm and at a temperature of 30°C.

4. The method for preparing composite biochar and bio-oil according to claim 1, characterized in that, In step S4, the waste mask biochar packs after adsorbing organic solution are placed in an oven at 105°C and dried to constant weight.

5. A composite biochar, characterized in that, The composite biochar and bio-oil were prepared according to any one of claims 1-4.

6. A bio-oil, characterized in that, The composite biochar and bio-oil were prepared according to any one of claims 1-4.

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