Preparation process of modified energy storage material taking biomass waste as raw material

Abstract

The present application relates to a kind of preparation process of modified energy storage material with biomass waste as raw material.The preparation process of modified energy storage material includes the pretreatment of biomass raw material, the preparation of chemical modifier, chemical modification, heat treatment, high-temperature carbonization, crushing and screening, pressing forming and the like.Prepared modified energy storage material has the advantages of renewability, low carbon environmental protection, three-dimensional structure controllable, force thermal performance compatible, etc., can provide strong support for sustainable development and green energy transformation, promote the harmonious development of economy, society and environment.

Description

Technical Field

[0001] A preparation process for modified energy storage materials using biomass waste as raw material belongs to the field of novel energy storage materials. Background Technology

[0002] With the continuous growth of global energy demand and the increasing severity of environmental pollution, the search for efficient, clean, and sustainable energy storage solutions has become a research hotspot in the field of science and technology. Biomass waste, as a renewable resource, has become a key research focus in the field of energy storage materials due to its wide availability, environmental friendliness, and potential high energy density. However, direct application of biomass waste often suffers from low energy density and poor stability, requiring modification to improve its performance as an energy storage material.

[0003] Traditional methods for modifying biomass waste mainly include physical, chemical, and biological modification. Physical modification methods, such as ball milling and pyrolysis, are simple to operate but often fail to achieve deep modification and performance improvement of the waste. Chemical modification methods introduce chemical reagents or catalysts to regulate the structure and function of waste, but often involve complex chemical reactions and high energy consumption. Biological modification methods utilize the action of microorganisms or enzymes to biotransform waste, but they are time-consuming, inefficient, and difficult to implement on a large scale. Summary of the Invention

[0004] In order to overcome the above-mentioned technical problems in the existing technical field, the purpose of this invention is to provide a preparation process for modified energy storage materials using biomass waste as raw material.

[0005] This invention provides a preparation process for modified energy storage materials using biomass waste as raw material, specifically comprising the following steps:

[0006] Step (1) Pretreatment of waste biomass raw materials

[0007] S11 Take an appropriate amount of wood processing waste into a microwave crusher, use the microwave crusher to quickly crush the waste, and then obtain biomass pellets with the required particle size distribution through screening.

[0008] S12 Add an appropriate amount of ligninase to the sieved biomass pellets;

[0009] S13 is again subjected to microwave assistance for a period of time;

[0010] S14 will screen the biomass waste that has undergone enzymatic hydrolysis to remove large particles and incompletely decomposed parts, and wash it with an appropriate amount of clean water to remove impurities and enzyme residues from the waste.

[0011] Step (2) Preparation of chemical modifier

[0012] S21 Dissolve an appropriate amount of 1-methylimidazolium and an appropriate amount of 1-bromobutane in an appropriate amount of acetone solvent;

[0013] S22 causes the reaction system to undergo a quaternization reaction at a certain temperature;

[0014] After the S23 reaction is completed, an appropriate amount of sodium tetrafluoroborate is added to the system to carry out an ionic reaction. After the reaction is completed, vacuum distillation is performed to obtain an imidazole ionic liquid.

[0015] S24 mixes polyacrylic acid and water in a certain proportion, heats to an appropriate temperature, and stirs until completely dissolved to form a uniform polyacrylic acid solution;

[0016] Step (3) Chemical modification of biomass raw materials

[0017] S31 Take an appropriate amount of pretreated biomass pellets, mix them with an appropriate amount of imidazole ionic liquid, and complete the modification pretreatment.

[0018] S32 involves immersing pretreated biomass waste in a polyacrylic acid solution while continuously stirring;

[0019] During the impregnation process, an appropriate amount of isocyanate is added to S33, and the functional groups of isocyanate are chemically bonded to the active groups in biomass waste and polyacrylic acid.

[0020] S34 sets the appropriate reaction temperature and time to carry out the modification reaction;

[0021] S35 adds an appropriate amount of potassium hydroxide to the reaction system and adjusts the pH value of the system to a suitable range, then stirs continuously and continues the reaction for a period of time;

[0022] After the reaction is complete, the reaction system is filtered and washed, and then dried at a suitable temperature to complete the chemical modification of the biomass raw material.

[0023] Step (4) Thermal treatment of biomass raw materials

[0024] S41 places an appropriate amount of chemically modified biomass raw material into a pyrolysis reactor and gradually heats it to the pyrolysis carbonization temperature range at a certain heating rate under nitrogen protection.

[0025] During the pyrolysis process, S42 uses a rotating reactor to achieve dynamic movement of biomass waste particles and maintain the reaction for a period of time.

[0026] After dynamic pyrolysis, S43 cools the resulting product to room temperature.

[0027] S44 The product is heated again to a suitable temperature at a certain heating rate and held for a certain time to carry out the recrystallization process;

[0028] After recrystallization of S45 is completed, the product is slowly cooled to room temperature to obtain the modified energy storage material raw material.

[0029] Step (5) Crushing and screening of modified energy storage raw materials

[0030] S51 places an appropriate amount of modified energy storage material raw material into the feed inlet of the air jet mill and performs pulverization under a certain airflow velocity;

[0031] S52 feeds the modified energy storage raw material after air jet pulverization into a screening machine. By utilizing the screening action and dynamic vibration of the screen, and under certain aperture and vibration frequency, modified energy storage raw material particles of appropriate particle size are obtained.

[0032] Step (6) Pressing and molding of modified energy storage materials

[0033] S61 places the pulverized and screened modified energy storage raw material particles into the mold of a hot press, and hot presses the material into shape under certain temperature and pressure.

[0034] After hot pressing, the S62 material is placed in a microwave curing device and further microwave-assisted curing is performed under certain microwave power, time and frequency parameters to finally obtain the modified energy storage material.

[0035] As a preferred embodiment, the pretreatment of waste biomass raw materials in step (1) includes the following steps: S11 Take 200~280g of wood processing waste into a microwave crusher, set the power parameter of the microwave crusher to 1000~1500W, crush for 20~50min, and then obtain 200~250 mesh biomass particles by sieving; S12 Add 2~5g of lignin enzyme to the sieved biomass particles; S13 Again use microwave assistance to set the microwave power to 200~500W, and react and enzymatically hydrolyze for 5~8h; S14 Screen the enzymatically hydrolyzed biomass waste to remove large particles and incompletely decomposed parts, and wash with 1~1.5L of clean water to remove impurities and enzyme residues in the waste.

[0036] This method innovatively utilizes microwave-assisted bio-enzymatic hydrolysis pretreatment to pretreat waste biomass raw materials. Microwave crushing leverages the thermal and non-thermal effects of microwaves to rapidly break down waste, achieving the desired particle size distribution and increasing its specific surface area, which also facilitates the subsequent enzymatic hydrolysis process. Adding ligninase to the microwave-crushed biomass waste allows the enzyme to break down its complex structure, converting it into simpler sugars or other usable small molecules. Furthermore, the microwave assistance during enzymatic hydrolysis accelerates the reaction rate between the enzyme and the waste.

[0037] As a preferred embodiment, the preparation of the chemical modifier in step (2) includes the following steps: S21 Dissolve 10~16g of 1-methylimidazolium and 5~11g of 1-bromobutane in 50~70mL of acetone solvent; S22 Allow the reaction system to undergo quaternization reaction at 40~55℃; S23 After the reaction is completed, add 12~18g of sodium tetrafluoroborate to the system for ionic reaction, and after the reaction is completed, perform vacuum distillation to obtain imidazolium-based ionic liquid; S24 Mix polyacrylic acid and water at a ratio of 1:(3~6), heat to 70~85℃, and stir until completely dissolved to form a uniform polyacrylic acid solution.

[0038] This method innovatively utilizes imidazole ionic liquids and polyacrylic acid solutions to composite modify biomass raw materials. The combination of imidazole ionic liquids and biomass waste not only utilizes waste resources but also reduces production costs, aligning with the principles of green chemistry and sustainable development. Through modification, previously useless biomass waste can be transformed into valuable energy storage materials, achieving resource utilization of waste. Imidazole ionic liquids possess unique ionic structures and properties, which can improve the electrochemical performance of biomass waste-based energy storage materials and enhance their energy storage efficiency. Furthermore, the composite use of imidazole ionic liquids and polyacrylic acid significantly enhances the electrochemical performance of biomass waste-based energy storage materials. Moreover, the composite modification of imidazole ionic liquids and polyacrylic acid strengthens the structural and chemical stability of biomass waste-based energy storage materials. This improved stability helps the materials maintain stable performance during long-term use, reducing performance degradation and extending the lifespan of the energy storage materials.

[0039] As a preferred embodiment, step (3) of chemical modification of biomass raw materials includes the following steps: S31 Take 150~180g of pretreated biomass particles, mix them with 20~30mL of imidazole ionic liquid and complete the modification pretreatment; S32 Immerse the biomass waste pretreated with ionic liquid in 50~80mL of polyacrylic acid solution and stir continuously; S33 During the immersion process, add 18~24mL of isocyanate, and chemically bond the functional groups of isocyanate with the active groups in biomass waste and polyacrylic acid; S34 Set the reaction time to 4~7h and the reaction temperature to 80~110℃ for pre-reaction; S35 Add 10~18mL of potassium hydroxide to the reaction system and adjust the pH value of the system to 8~10, and then stir continuously for 2~5h; S36 After the reaction is completed, filter and wash the reaction system and dry it at 50~80℃ to complete the chemical modification of waste biomass raw materials.

[0040] In this method, isocyanate is used as a crosslinking agent, and further modification is achieved through the composite modification of imidazole ionic liquid and polyacrylic acid. The active groups in biomass waste and polyacrylic acid undergo chemical bonding and reaction to achieve deep crosslinking and further chemical modification, forming a three-dimensional network structure, thereby improving the structural stability of the material. Deep co-crosslinking can significantly enhance the structural stability of biomass particles, enabling them to maintain good performance even under harsh environments such as high temperature and high humidity. Through functional modification, biomass particles can possess a variety of functional properties to meet the application needs of different fields.

[0041] Preferably, step (4) the thermal treatment of biomass raw materials includes the following steps: S41 80~120g of chemically modified biomass raw materials are placed in a pyrolysis reactor and heated to 300~360℃ at a heating rate of 3~6℃ / min under nitrogen protection and pyrolyzed and carbonized; S42 During the pyrolysis process, the biomass waste particles are dynamically moved by rotating the reactor and the reaction is maintained for 1~4h; S43 After the dynamic pyrolysis is completed, the obtained product is cooled to room temperature; S44 The product is heated again to 320~380℃ at a heating rate of 3~6℃ / min and maintained for 3~6h for recrystallization; S45 After recrystallization is completed, the product is slowly cooled to room temperature to obtain modified energy storage material raw materials.

[0042] This method employs dynamic pyrolysis and recrystallization in the thermal treatment of biomass raw materials. During pyrolysis, a rotating reactor enables dynamic movement of the biomass waste particles, promoting uniform pyrolysis. Dynamic pyrolysis effectively prevents agglomeration or clumping of biomass waste during the process and promotes the uniform release of volatile substances. Following dynamic pyrolysis, the crystallinity and crystal structure of the product can be controlled by adjusting temperature and time during recrystallization, thereby optimizing its thermal stability and energy storage performance. The combination of dynamic pyrolysis and recrystallization promotes the crystallization process of biomass waste-based materials, increasing their crystallinity and enhancing their thermal stability and energy storage performance. This combined dynamic pyrolysis and recrystallization thermal treatment method is innovative in the preparation of biomass waste-based modified energy storage materials, providing a new approach to improving material performance.

[0043] Preferably, step (5) of pulverizing and sieving the modified energy storage material includes the following steps: S51 Place 60~90g of modified energy storage material in the feed inlet of an air jet mill and pulverize it at an airflow speed of 300~600m / s; S52 Feed the modified energy storage material after air jet pulverization into a screening machine, and obtain modified energy storage material particles of 30~60 micrometers by using the screening effect of the screen and dynamic vibration, and at a pore size of 50~80 micrometers and a vibration frequency of 1000~5000 times / minute.

[0044] In this method, modified energy storage raw materials are subjected to air jet milling and dynamic screening. Air jet milling enables ultrafine grinding of biomass waste, resulting in smaller and more uniform particles, which is beneficial to improving the performance of energy storage materials. Dynamic screening, through a vibrating device, achieves dynamic vibration of the screen, enabling real-time screening of materials and avoiding blockage and secondary breakage during the screening process. The combination of air jet milling and dynamic screening achieves continuous grinding and screening, improving the overall process efficiency.

[0045] Preferably, step (6) of pressing the modified energy storage material includes the following steps: S61 The pulverized and sieved modified energy storage raw material particles are placed in the mold of a hot press, and the material is hot-pressed at a temperature of 100~160℃ and a pressure of 5~11MPa; S62 After the hot pressing is completed, the initially formed energy storage material is placed in a microwave curing device, and further microwave-assisted curing is carried out under parameters such as microwave power of 500~800W, time of 10~40min and frequency of 3~5GHz to finally obtain the modified energy storage material.

[0046] This method innovatively utilizes hot pressing and microwave-assisted curing processes in the compression molding of modified energy storage materials. Under specific temperature and pressure conditions, the material is hot-pressed. By controlling the magnitude and duration of temperature, pressure, and pressure, the material is allowed to fully flow and reshape within the mold, forming the desired shape and size. Hot pressing leverages temperature and pressure to ensure the biomass waste flows and reshapes within the mold, achieving efficient and uniform molding. Microwaves, with their uniform heating properties, rapidly cure the material. Microwave energy can quickly penetrate the material's interior, promoting internal cross-linking reactions and crystallization processes, thus improving the material's density and mechanical properties. Microwave-assisted curing, utilizing the uniform heating properties of microwaves, can rapidly promote internal cross-linking reactions and crystallization processes, increasing curing speed and shortening the process cycle. The microwave curing process requires no additional heating medium, reducing energy consumption and environmental pollution.

[0047] The modified energy storage material prepared by this method using biomass waste as raw material has advantages such as renewability, low carbon emissions, environmental friendliness, controllable three-dimensional structure, and compatibility of mechanical and thermal properties. It can provide strong support for sustainable development and green energy transition, and promote the harmonious development of economy, society and environment. Attached Figure Description

[0048] Figure 1 This is a process flow diagram for the preparation of modified energy storage materials using biomass waste as raw materials. Detailed Implementation

[0049] Example 1

[0050] This invention provides a preparation process for modified energy storage materials using biomass waste as raw material, specifically comprising the following steps:

[0051] Step (1) Pretreatment of waste biomass raw materials

[0052] S11 Take 200g of wood processing waste and put it into a microwave crusher. Set the power parameter of the microwave crusher to 1000W and crush for 20 minutes. Then, obtain 200-mesh biomass pellets by screening.

[0053] S12 Add 2g of ligninase to the sieved biomass pellets;

[0054] S13 was again set to microwave power at 200W with microwave assistance and enzymatic hydrolysis was carried out for 5 hours.

[0055] S14 will screen the enzymatically hydrolyzed biomass waste to remove large particles and incompletely decomposed parts, and wash it with 1L of clean water to remove impurities and enzyme residues from the waste.

[0056] Step (2) Preparation of chemical modifier

[0057] S21 Dissolve 10g of 1-methylimidazolium and 5g of 1-bromobutane in 50mL of acetone solvent;

[0058] S22 is used to carry out a quaternization reaction in the reaction system at 40℃;

[0059] After the S23 reaction is completed, 12g of sodium tetrafluoroborate is added to the system to carry out an ionic reaction. After the reaction is completed, vacuum distillation is performed to obtain an imidazole ionic liquid.

[0060] S24 mixes polyacrylic acid and water at a ratio of 1:3, heats to 70°C, and stirs until completely dissolved to form a homogeneous polyacrylic acid solution;

[0061] Step (3) Chemical modification of biomass raw materials

[0062] S31 Take 150g of pretreated biomass pellets, mix them with 20mL of imidazole ionic liquid, and complete the modification pretreatment;

[0063] S32 immerses the biomass waste pretreated with ionic liquid in 50 mL of polyacrylic acid solution while continuously stirring;

[0064] During the impregnation process, 18 mL of isocyanate is added to S33, and the functional groups of isocyanate are chemically bonded to the active groups in biomass waste and polyacrylic acid.

[0065] S34 is set to a reaction time of 4 hours and a reaction temperature of 80℃ for pre-reaction.

[0066] S35 added 10 mL of potassium hydroxide to the reaction system and adjusted the pH of the system to 8, then stirred continuously for 2 hours to continue the reaction.

[0067] After the reaction is complete, the reaction system is filtered and washed, and then dried at 50°C to complete the chemical modification of the waste biomass raw material.

[0068] Step (4) Thermal treatment of biomass raw materials

[0069] S41 places 80g of chemically modified biomass raw material in a pyrolysis reactor, and under nitrogen protection, gradually heats it to 300℃ at a heating rate of 3℃ / min and carries out pyrolysis and carbonization.

[0070] During the pyrolysis process, S42 uses a rotating reactor to achieve dynamic movement of biomass waste particles and maintain the reaction for 1 hour.

[0071] After dynamic pyrolysis, S43 cools the resulting product to room temperature.

[0072] S44 The product was heated again to 320°C at a heating rate of 3°C / min and held for 3 hours for recrystallization.

[0073] After recrystallization of S45 is completed, the product is slowly cooled to room temperature to obtain the modified energy storage material raw material.

[0074] Step (5) Crushing and screening of modified energy storage raw materials

[0075] S51 places 60g of modified energy storage material raw material into the feed inlet of an air jet mill and pulverizes it at an airflow velocity of 300m / s.

[0076] S52 feeds the modified energy storage raw material after air jet pulverization into a screening machine. Utilizing the screening action of the screen and dynamic vibration, and with a pore size of 50 micrometers and a vibration frequency of 1000 times / minute, 30-micrometer modified energy storage raw material particles are obtained.

[0077] Step (6) Pressing and molding of modified energy storage materials

[0078] S61 places the pulverized and screened modified energy storage raw material particles into the mold of a hot press, and hot presses the material at a temperature of 100°C and a pressure of 5MPa.

[0079] After hot pressing, the S62 material is placed in a microwave curing device and further microwave-assisted curing is performed under parameters such as 500W microwave power, 10 minutes time and 3GHz frequency to finally obtain the modified energy storage material.

[0080] Example 2

[0081] Step (1) Pretreatment of waste biomass raw materials

[0082] S11 Take 220g of wood processing waste and put it into a microwave crusher. Set the power parameter of the microwave crusher to 1100W and crush for 30 minutes. Then, obtain 210 mesh biomass pellets by screening.

[0083] S12 Add 3g of ligninase to the sieved biomass pellets;

[0084] S13 was again set to 300W with microwave assistance and the enzymatic hydrolysis was carried out for 6 hours.

[0085] S14 will screen the enzymatically hydrolyzed biomass waste to remove large particles and incompletely decomposed parts, and wash it with 1.1L of clean water to remove impurities and enzyme residues from the waste.

[0086] Step (2) Preparation of chemical modifier

[0087] S21 Dissolve 12g of 1-methylimidazolium and 7g of 1-bromobutane in 55mL of acetone solvent;

[0088] S22 is used to carry out a quaternization reaction in the reaction system at 45℃;

[0089] After the S23 reaction is completed, 14g of sodium tetrafluoroborate is added to the system to carry out an ionic reaction. After the reaction is completed, vacuum distillation is performed to obtain an imidazole ionic liquid.

[0090] S24 mixes polyacrylic acid and water at a ratio of 1:4, heats to 75°C, and stirs until completely dissolved to form a homogeneous polyacrylic acid solution;

[0091] Step (3) Chemical modification of biomass raw materials

[0092] S31 Take 160g of pretreated biomass pellets, mix them with 23mL of imidazole ionic liquid, and complete the modification pretreatment.

[0093] S32 immerses the biomass waste pretreated with ionic liquid in 60 mL of polyacrylic acid solution while continuously stirring;

[0094] During the impregnation process, 20 mL of isocyanate is added to S33, and the functional groups of isocyanate are chemically bonded to the active groups in biomass waste and polyacrylic acid.

[0095] S34 is set to a reaction time of 5 hours and a reaction temperature of 90°C for pre-reaction.

[0096] S35 added 12 mL of potassium hydroxide to the reaction system and adjusted the pH of the system to 8.5, then stirred continuously for 3 hours to continue the reaction.

[0097] After the reaction is complete, the reaction system is filtered and washed, and then dried at 60°C to complete the chemical modification of the waste biomass raw material.

[0098] Step (4) Thermal treatment of biomass raw materials

[0099] S41 places 90g of chemically modified biomass raw material in a pyrolysis reactor, and under nitrogen protection, gradually heats it to 320℃ at a heating rate of 4℃ / min and carries out pyrolysis and carbonization.

[0100] During the pyrolysis process, S42 uses a rotating reactor to achieve dynamic movement of biomass waste particles and maintain the reaction for 2 hours.

[0101] After dynamic pyrolysis, S43 cools the resulting product to room temperature.

[0102] S44 The product was heated again to 340℃ at a heating rate of 4℃ / min and held for 4h for recrystallization.

[0103] After recrystallization of S45 is completed, the product is slowly cooled to room temperature to obtain the modified energy storage material raw material.

[0104] Step (5) Crushing and screening of modified energy storage raw materials

[0105] S51 places 70g of modified energy storage material raw material into the feed inlet of an air jet mill and pulverizes it at an airflow velocity of 400m / s.

[0106] S52 feeds the modified energy storage raw material after air jet pulverization into a screening machine. Utilizing the screening action of the screen and dynamic vibration, and with a pore size of 60 micrometers and a vibration frequency of 2000 times / minute, it obtains modified energy storage raw material particles of 40 micrometers.

[0107] Step (6) Pressing and molding of modified energy storage materials

[0108] S61 places the pulverized and screened modified energy storage raw material particles into the mold of a hot press, and hot presses the material at a temperature of 120°C and a pressure of 7MPa.

[0109] After hot pressing, the S62 material is placed in a microwave curing device and further microwave-assisted curing is performed under parameters such as 600W microwave power, 20 minutes time and 3.5GHz frequency to finally obtain the modified energy storage material.

[0110] Example 3

[0111] Step (1) Pretreatment of waste biomass raw materials

[0112] S11 Take 260g of wood processing waste and put it into a microwave crusher. Set the power parameter of the microwave crusher to 1300W and crush for 40 minutes. Then, obtain 240-mesh biomass pellets by screening.

[0113] S12 Add 4g of ligninase to the sieved biomass pellets;

[0114] S13 was again set to 400W with microwave assistance and the enzymatic hydrolysis was carried out for 7 hours.

[0115] S14 will screen the enzymatically hydrolyzed biomass waste to remove large particles and incompletely decomposed parts, and wash it with 1.3L of clean water to remove impurities and enzyme residues from the waste.

[0116] Step (2) Preparation of chemical modifier

[0117] S21 Dissolve 14g of 1-methylimidazolium and 9g of 1-bromobutane in 60mL of acetone solvent;

[0118] S22 is used to carry out a quaternization reaction in the reaction system at 50℃;

[0119] After the S23 reaction is completed, 16g of sodium tetrafluoroborate is added to the system to carry out an ionic reaction. After the reaction is completed, vacuum distillation is performed to obtain an imidazole ionic liquid.

[0120] S24 mixes polyacrylic acid and water at a ratio of 1:5, heats to 80°C, and stirs until completely dissolved to form a homogeneous polyacrylic acid solution;

[0121] Step (3) Chemical modification of biomass raw materials

[0122] S31 Take 170g of pretreated biomass pellets, mix them with 26mL of imidazole ionic liquid, and complete the modification pretreatment.

[0123] S32 immerses the biomass waste pretreated with ionic liquid in 70 mL of polyacrylic acid solution while continuously stirring;

[0124] During the impregnation process, 22 mL of isocyanate is added to S33, and the functional groups of isocyanate are chemically bonded to the active groups in biomass waste and polyacrylic acid.

[0125] S34 was pre-reacted with a reaction time of 6 hours and a reaction temperature of 100°C.

[0126] S35 added 16 mL of potassium hydroxide to the reaction system and adjusted the pH of the system to 9, then stirred continuously for 4 h to continue the reaction;

[0127] After the reaction is complete, the reaction system is filtered and washed, and then dried at 70°C to complete the chemical modification of the waste biomass raw material.

[0128] Step (4) Thermal treatment of biomass raw materials

[0129] S41 places 100g of chemically modified biomass raw material in a pyrolysis reactor, and under nitrogen protection, gradually heats it to 340℃ at a heating rate of 5℃ / min and carries out pyrolysis and carbonization.

[0130] During the pyrolysis process, S42 uses a rotating reactor to achieve dynamic movement of biomass waste particles and maintain the reaction for 3 hours.

[0131] After dynamic pyrolysis, S43 cools the resulting product to room temperature.

[0132] S44 The product was heated again to 360°C at a heating rate of 5°C / min and held for 5 hours for recrystallization.

[0133] After recrystallization of S45 is completed, the product is slowly cooled to room temperature to obtain the modified energy storage material raw material.

[0134] Step (5) Crushing and screening of modified energy storage raw materials

[0135] S51 places 80g of modified energy storage material raw material into the feed inlet of an air jet mill and pulverizes it at an airflow velocity of 500m / s.

[0136] S52 feeds the modified energy storage raw material after air jet pulverization into a screening machine. Utilizing the screening action of the screen and dynamic vibration, and with a pore size of 70 micrometers and a vibration frequency of 4000 times / minute, it obtains modified energy storage raw material particles of 50 micrometers.

[0137] Step (6) Pressing and molding of modified energy storage materials

[0138] S61 places the pulverized and screened modified energy storage raw material particles into the mold of a hot press, and hot presses the material at a temperature of 150°C and a pressure of 9MPa.

[0139] After hot pressing, the S62 material is placed in a microwave curing device and further microwave-assisted curing is performed under parameters such as 700W microwave power, 30 minutes time and 4GHz frequency to finally obtain the modified energy storage material.

[0140] Example 4

[0141] Step (1) Pretreatment of waste biomass raw materials

[0142] S11 Take 280g of wood processing waste and put it into a microwave crusher. Set the power parameter of the microwave crusher to 1500W and crush for 50 minutes. Then, obtain 250-mesh biomass pellets by screening.

[0143] S12 Add 5g of ligninase to the sieved biomass pellets;

[0144] S13 was again set to microwave power at 500W with microwave assistance and enzymatic hydrolysis was carried out for 8 hours.

[0145] S14 will screen the enzymatically hydrolyzed biomass waste to remove large particles and incompletely decomposed parts, and wash it with 1.5L of clean water to remove impurities and enzyme residues from the waste.

[0146] Step (2) Preparation of chemical modifier

[0147] S21 Dissolve 16g of 1-methylimidazolium and 11g of 1-bromobutane in 70mL of acetone solvent;

[0148] S22 is used to carry out a quaternization reaction in the reaction system at 55℃;

[0149] After the S23 reaction is completed, 18g of sodium tetrafluoroborate is added to the system to carry out an ionic reaction. After the reaction is completed, vacuum distillation is performed to obtain an imidazole ionic liquid.

[0150] S24 mixes polyacrylic acid and water at a ratio of 1:6, heats to 85°C, and stirs until completely dissolved to form a homogeneous polyacrylic acid solution;

[0151] Step (3) Chemical modification of biomass raw materials

[0152] S31 Take 180g of pretreated biomass pellets, mix them with 30mL of imidazole ionic liquid, and complete the modification pretreatment;

[0153] S32 immerses the biomass waste pretreated with ionic liquid in 80 mL of polyacrylic acid solution while continuously stirring;

[0154] During the impregnation process, 24 mL of isocyanate is added to S33, and the functional groups of isocyanate are chemically bonded to the active groups in biomass waste and polyacrylic acid.

[0155] S34 was pre-reacted with a reaction time of 7 hours and a reaction temperature of 110°C.

[0156] S35 added 18 mL of potassium hydroxide to the reaction system and adjusted the pH of the system to 10, then stirred continuously for 5 h to continue the reaction;

[0157] After the reaction is complete, the reaction system is filtered and washed, and then dried at 80°C to complete the chemical modification of the waste biomass raw material.

[0158] Step (4) Thermal treatment of biomass raw materials

[0159] S41 places 120g of chemically modified biomass raw material into a pyrolysis reactor, and under nitrogen protection, gradually heats it to 360℃ at a heating rate of 6℃ / min and carries out pyrolysis and carbonization.

[0160] During the pyrolysis process, S42 uses a rotating reactor to achieve dynamic movement of biomass waste particles and maintain the reaction for 4 hours.

[0161] After dynamic pyrolysis, S43 cools the resulting product to room temperature.

[0162] S44 The product was heated again to 380°C at a heating rate of 6°C / min and held for 6 hours for recrystallization.

[0163] After recrystallization of S45 is completed, the product is slowly cooled to room temperature to obtain the modified energy storage material raw material.

[0164] Step (5) Crushing and screening of modified energy storage raw materials

[0165] S51 places 90g of modified energy storage material raw material into the feed inlet of an air jet mill and pulverizes it at an airflow velocity of 600m / s.

[0166] S52 feeds the modified energy storage raw material after air jet pulverization into a screening machine. Utilizing the screening action of the screen and dynamic vibration, and with an 80-micron aperture and a vibration frequency of 5000 times / minute, 60-micron modified energy storage raw material particles are obtained.

[0167] Step (6) Pressing and molding of modified energy storage materials

[0168] S61 places the pulverized and screened modified energy storage raw material particles into the mold of a hot press, and hot presses the material at a temperature of 160°C and a pressure of 11MPa.

[0169] After hot pressing, the S62 material is placed in a microwave curing device and further microwave-assisted curing is performed under parameters such as 800W microwave power, 40 minutes time and 5GHz frequency to finally obtain the modified energy storage material.

[0170] Comparative Example 1

[0171] Step (1) Pretreatment of waste biomass raw materials

[0172] Take 200g of wood processing waste and put it into a microwave crusher. Set the power parameter of the microwave crusher to 1000W and crush for 20 minutes. Then, obtain 200-mesh biomass pellets by screening.

[0173] Step (2) Chemical modification of biomass raw materials

[0174] S21 Take 150g of pretreated biomass pellets, add 20mL of isocyanate and stir for 20min;

[0175] S22 is set to a reaction time of 4 hours and a reaction temperature of 80℃ for pre-reaction;

[0176] S23 added 10 mL of potassium hydroxide to the reaction system and adjusted the pH of the system to 8, then stirred continuously for 2 h to continue the reaction;

[0177] After the reaction is complete, the reaction system is filtered and washed, and then dried at 50°C to complete the chemical modification of the waste biomass raw material.

[0178] Step (3) Thermal treatment of biomass raw materials

[0179] S31 places 80g of chemically modified biomass raw material in a pyrolysis reactor, and under nitrogen protection, gradually heats it to 300℃ at a heating rate of 3℃ / min and carries out pyrolysis and carbonization.

[0180] S32 The product was heated again to 320℃ at a heating rate of 3℃ / min and held for 3h to carry out recrystallization.

[0181] After recrystallization of S33 is completed, the product is slowly cooled to room temperature to obtain the modified energy storage material raw material.

[0182] Step (4) Crushing and screening of modified energy storage raw materials

[0183] S41 places 60g of modified energy storage material raw material into the feed inlet of an air jet mill and pulverizes it at an airflow velocity of 300m / s.

[0184] S42 feeds the modified energy storage raw material after air jet pulverization into a screening machine. Utilizing the screening action of the screen and dynamic vibration, and with a pore size of 50 micrometers and a vibration frequency of 1000 times / minute, 30-micrometer modified energy storage raw material particles are obtained.

[0185] Step (5) Compression molding of modified energy storage materials

[0186] S51 places the pulverized and sieved modified energy storage raw material particles into the mold of a hot press, and hot presses the material at a temperature of 100°C and a pressure of 5MPa to obtain the modified energy storage material.

[0187] Comparative Example 2

[0188] Step (1) Pretreatment of waste biomass raw materials

[0189] Take 280g of wood processing waste and put it into a microwave crusher. Set the power parameter of the microwave crusher to 1500W and crush for 50 minutes. Then, obtain 250-mesh biomass pellets by screening.

[0190] Step (2) Chemical modification of biomass raw materials

[0191] S21 Take 180g of pretreated biomass pellets, add 24mL of isocyanate and stir for 50min;

[0192] S22 is set to a reaction time of 7 hours and a reaction temperature of 110℃ for pre-reaction;

[0193] S23 added 18 mL of potassium hydroxide to the reaction system and adjusted the pH of the system to 10, then stirred continuously for 5 h to continue the reaction;

[0194] After the reaction is complete, the reaction system is filtered and washed, and then dried at 80°C to complete the chemical modification of the waste biomass raw material.

[0195] Step (3) Thermal treatment of biomass raw materials

[0196] S31 places 120g of chemically modified biomass raw material in a pyrolysis reactor, and under nitrogen protection, gradually heats it to 360℃ at a heating rate of 6℃ / min and carries out pyrolysis and carbonization.

[0197] S32 The product was heated again to 380℃ at a heating rate of 6℃ / min and held for 6h for recrystallization.

[0198] After recrystallization of S33 is completed, the product is slowly cooled to room temperature to obtain the modified energy storage material raw material.

[0199] Step (4) Crushing and screening of modified energy storage raw materials

[0200] S41 places 90g of modified energy storage material raw material into the feed inlet of an air jet mill and pulverizes it at an airflow velocity of 600m / s.

[0201] S42 feeds the modified energy storage raw material after air jet pulverization into a screening machine. Utilizing the screening action of the screen and dynamic vibration, and with an 80-micron aperture and a vibration frequency of 5000 times / minute, 60-micron modified energy storage raw material particles are obtained.

[0202] Step (5) Compression molding of modified energy storage materials

[0203] S51 places the pulverized and sieved modified energy storage raw material particles into the mold of a hot press, and hot presses the material at a temperature of 160°C and a pressure of 11MPa to obtain the modified energy storage material.

[0204] The modified energy storage materials obtained in Examples 1 to 4 and the products of Comparative Examples 1 and 2 were tested using the following specific testing methods:

[0205] True density test

[0206] The modified energy storage materials prepared in the examples and comparative examples were tested for true density using a BSD-TD-K fully automatic true density and porosity analyzer. The samples were first crushed and then loaded into the measuring chamber. The densitometer was started to begin the gas replacement process. After the measurement was completed, the instrument readings were read.

[0207] Thermal storage performance test

[0208] The modified energy storage materials prepared in the examples and comparative examples were placed in a DGG105 vacuum drying oven, and the corresponding temperature was set to 60°C. After storage for 12 hours, the temperature was slowly restored to room temperature, and the mass loss before and after thermal storage was measured.

[0209] Table 1. Results of True Density Test

[0210] Example <![CDATA[True density (g / cm 3 ).]]> 1 0.96 2 1.13 3 1.26 4 1.35 Comparative Example 1 0.56 Comparative Example 2 0.68

[0211] Table 1 shows that the actual density of the modified energy storage materials prepared in Examples 1-4 is greater than that of the modified energy storage materials prepared in Comparative Examples 1 and 2. In the preparation process, these examples creatively used a microwave-assisted bio-enzymatic hydrolysis pretreatment method to pretreat the waste biomass raw materials. Microwave crushing utilizes the thermal and non-thermal effects of microwaves to rapidly crush the waste, achieving the desired particle size distribution and increasing the specific surface area of ​​the waste. Ligninase is added to the microwave-crushed biomass waste, which decomposes the complex structure of the biomass waste, converting it into simpler sugars or other usable small molecules. Furthermore, the use of microwave assistance during enzymatic hydrolysis accelerates the reaction rate between the enzyme and the waste, resulting in a higher actual density of the final modified energy storage material. Higher density means greater mass, thus leading to a higher total energy storage capacity.

[0212] Table 2 Thermal storage performance test results

[0213] Example Quality loss (%) 1 1.45 2 1.26 3 1.18 4 0.96 Comparative Example 1 4.69 Comparative Example 2 4.35

[0214] Table 2 shows that the mass loss of the modified energy storage materials prepared in Examples 1-4 is less than that of the phase change wound biomass energy storage substrates prepared in Comparative Examples 1 and 2, and less than 1.5%. In these examples, a microwave-assisted bio-enzymatic pretreatment method was used to pretreat the biomass raw materials, effectively improving the structure of the biomass raw materials and removing impurities and inhibitors, thereby improving the performance of the final product. Furthermore, a dynamic pyrolysis process was incorporated into the heat treatment of the biomass raw materials. During pyrolysis, a rotating reactor was used to achieve dynamic movement of the biomass waste particles, promoting the uniformity of the pyrolysis reaction. Dynamic pyrolysis can effectively prevent the biomass waste from agglomerating or clumping during pyrolysis, while also promoting the uniform release of volatile substances. Microwave-assisted curing was also creatively combined in the pressing and molding of the modified energy storage materials. Microwave energy can rapidly penetrate the interior of the material, promoting internal cross-linking reactions and crystallization processes, improving the material's density and mechanical properties. Microwave-assisted curing utilizes the uniform heating characteristics of microwaves to rapidly promote internal cross-linking reactions and crystallization processes, thereby improving the energy storage capacity of the modified energy storage materials. Furthermore, the embodiments utilize imidazole ionic liquids, polyacrylic acid, and isocyanate for multiple composite modifications, which effectively improves the thermal and chemical stability of the modified energy storage material and enhances its energy storage performance.

[0215] This specific embodiment is merely an explanation of the present invention and is not intended to limit the present invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but as long as they are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A process for the preparation of modified energy storage material using biomass waste as a raw material, characterized by Comprise: Step (1) pretreatment of waste biomass raw materials S11 take a proper amount of wood processing waste into a microwave crusher, use the microwave crusher to quickly crush the waste, and then obtain biomass particles with the desired particle size distribution by sieving; S12 add a proper amount of ligninase to the sieved biomass particles; S13 use microwave assistance again and react for a period of time; S14 sieve the biomass waste treated by enzymolysis, remove large particles and incompletely decomposed parts, and wash with a proper amount of water to remove impurities and enzyme residues in the waste; Step (2) preparation of chemical modifier S21 dissolve a proper amount of 1-methylimidazole and a proper amount of 1-bromobutane in a proper amount of acetone solvent; S22 make the reaction system undergo quaternary ammonium reaction at a certain temperature; S23 after the reaction is completed, add a proper amount of sodium tetrafluoroborate to the system to undergo ion reaction, and vacuum distillation after the reaction is completed to obtain imidazole ionic liquid; S24 mix polyacrylic acid with water in a certain proportion, heat to an appropriate temperature, stir until completely dissolved, and form a uniform polyacrylic acid solution; Step (3) chemical modification of biomass raw materials S31 take a proper amount of pretreated biomass particles, mix with a proper amount of imidazole ionic liquid, and complete the modification pretreatment; S32 immerse the biomass waste treated by ionic liquid in the polyacrylic acid solution and continuously stir; S33 during the immersion process, add a proper amount of isocyanate, and chemically bond the active groups in the biomass waste and polyacrylic acid through the functional groups of isocyanate; S34 set the corresponding reaction temperature and time for modification reaction; S35 add a proper amount of potassium hydroxide to the reaction system and adjust the pH value of the system to an appropriate range, then continuously stir and continue to react for a period of time; S36 after the reaction is completed, filter and wash the reaction system, and dry at an appropriate temperature to complete the chemical modification of the biomass raw materials; Step (4) heat treatment of biomass raw materials S41 place a proper amount of chemically modified biomass raw materials in a pyrolysis reactor, gradually heat to the pyrolysis carbonization temperature range at a certain heating rate under nitrogen protection; S42 during pyrolysis, realize the dynamic movement of biomass waste particles by rotating the reactor and maintain the reaction for a period of time; S43 after dynamic pyrolysis, cool the obtained product to room temperature; S44 heat the product to an appropriate temperature at a certain heating rate again, and maintain a certain time for recrystallization process; S45 after recrystallization is completed, slowly cool the product to room temperature to obtain modified energy storage material raw materials; Step (5) crushing and sieving of modified energy storage raw materials S51 place a proper amount of modified energy storage material raw materials in the feed inlet of an air flow crusher, and perform crushing treatment at a certain air flow speed; S52 send the modified energy storage raw materials after air flow crushing into a screening machine, use the screening effect and dynamic vibration of the screen mesh, and obtain modified energy storage raw material particles with appropriate particle size at a certain pore size and vibration frequency; Step (6) compression molding of modified energy storage material S61 the modified energy storage raw material particles after crushing and screening are placed in the mold of a hot press, and the material is hot-pressed at a certain temperature and pressure; S62 after the hot-pressing is completed, the preliminarily formed energy storage material is placed in a microwave curing device, and further microwave-assisted curing is performed at certain microwave power, time and frequency parameters to finally obtain the modified energy storage material.

2. The process according to claim 1, wherein the biomass waste is selected from the group consisting of rice straw, corn stalk, cotton stalk, and bagasse. Step (1) pretreatment of the waste biomass raw material comprises the following steps: S11 200-280g of wood processing waste is taken into a microwave crusher, the microwave crusher is set to a power parameter of 1000-1500W, and crushing is performed for 20-50min, and then 200-250 mesh biomass particles are obtained through screening; S12 2-5g of ligninase is added to the screened biomass particles; S13 microwave assistance is used again, the microwave power is set to 200-500W, and enzymatic hydrolysis is performed for 5-8h; S14 the biomass waste treated by enzymatic hydrolysis is screened to remove large particles and incompletely decomposed parts, and 1-1.5L of clean water is used for washing to remove impurities and enzyme residues in the waste.

3. The process according to claim 1, wherein the biomass waste is selected from the group consisting of rice straw, corn stalk, cotton stalk, and bagasse. Step (2) preparation of the chemical modifier comprises the following steps: S21 10-16g of 1-methylimidazole and 5-11g of 1-bromobutane are dissolved in 50-70mL of acetone solvent; S22 the reaction system is allowed to perform quaternary ammonium reaction at 40-55℃; S23 after the reaction is completed, 12-18g of sodium tetrafluoroborate is added to the system to perform ion reaction, and after the reaction is completed, vacuum distillation is performed to obtain an imidazole-based ionic liquid; S24 polyacrylic acid is mixed with water at a ratio of 1:(3-6), heated to a temperature of 70-85℃, and stirred until completely dissolved to form a uniform polyacrylic acid solution.

4. The process according to claim 1, wherein the biomass waste is selected from the group consisting of rice straw, corn stalk, cotton stalk, and bagasse. Step (2) chemical modification of the biomass raw material comprises the following steps: S31 150-180g of the pretreated biomass particles are mixed with 20-30mL of the imidazole-based ionic liquid to complete the modification pretreatment; S32 the biomass waste treated by the ionic liquid is immersed in 50-80mL of the polyacrylic acid solution and continuously stirred; S33 during the immersion process, 18-24mL of isocyanate is added to chemically bond with the active groups in the biomass waste and the polyacrylic acid through the functional groups of the isocyanate; S34 the reaction time is set to 4-7h, and the reaction temperature is 80-110℃ for pre-reaction; S35 10-18mL of potassium hydroxide is added to the reaction system to adjust the pH value of the system to 8-10, and then continuous stirring is performed for 2-5h of further reaction; S36 after the reaction is completed, the reaction system is filtered and washed, and dried at 50-80℃ to complete the chemical modification of the waste biomass raw material.

5. The process according to claim 1, wherein the biomass waste is selected from the group consisting of rice straw, corn stalk, cotton stalk, and bagasse. 5 Step (4) heat treatment of the biomass raw material comprises the following steps: S41 80-120g of the chemically modified biomass raw material is placed in a pyrolysis reactor, heated to 300-360℃ at a heating rate of 3-6℃ / min under nitrogen protection, and subjected to pyrolysis and carbonization. S42In the pyrolysis process, the dynamic movement of biomass waste particles is achieved by rotating the reactor, and the reaction is maintained for 1-4 hours; S43After the dynamic pyrolysis is completed, the obtained product is cooled to room temperature; S44The product is heated again to 320-380℃ at a heating rate of 3-6℃ / min, and maintained for 3-6 hours for recrystallization process; S45After the recrystallization is completed, the product is slowly cooled to room temperature to obtain the modified energy storage material raw material.

6. The process according to claim 1, wherein the biomass waste is selected from the group consisting of rice straw, corn stalk, cotton stalk, and bagasse. Step (5) Pulverization and screening of modified energy storage raw material includes the following steps: S51Put 60-90g of modified energy storage material raw material into the feed inlet of the air flow pulverizer, and perform pulverization treatment at an air flow speed of 300-600m / s; S52Send the modified energy storage material after air flow pulverization into the screening machine, use the screening effect and dynamic vibration of the screen, and at a pore size of 50-80 microns and a vibration frequency of 1000-5000 times / min, obtain modified energy storage material particles of 30-60 microns.

7. The process according to claim 1, wherein the biomass waste is selected from the group consisting of rice straw, corn stalk, cotton stalk, and bagasse. Step (6) Compression molding of modified energy storage material includes the following steps: S61Put the modified energy storage material particles after pulverization and screening into the mold of the hot press, and perform hot press molding on the material at a temperature of 100-160℃ and a pressure of 5-11MPa; S62After the hot press molding is completed, place the preliminary molded energy storage material in the microwave curing equipment, and perform further microwave-assisted curing under the parameters of microwave power of 500-800W, time of 10-40min, and frequency of 3-5GHz, to finally obtain the modified energy storage material.

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