阅读说明：本技术 一种废弃塑料改性定型相变材料储热工质的制备方法 (Preparation method of waste plastic modified and shaped phase-change material heat storage working medium ) 是由 刘昌会 刘健 杨旭龙 张耀东 王佳鹏 于 2021-10-21 设计创作，主要内容包括：本发明公开了一种废弃塑料改性定型相变材料储热工质的制备方法,将收集来的废弃塑料进行分类粉碎,然后分别用酒精进行冲洗提纯,得到较为干净的废弃塑料；将干净的废气塑料放入管式炉中进行废弃塑料热解,废弃塑料完全热解成富碳的氢化合物挥发物前驱原料,接着进行碳的气相沉积,然后进行增强碳骨架,最后自然降温至室温得到多孔碳材料；将石蜡熔融,并使用真空浸滞的方法将熔融的石蜡融入上述多孔碳材料中,使石蜡完全被多孔碳材料吸收,取出多孔碳材料并在真空下干燥,得到定型相变材料储热工质。为了架构起废弃塑料高值转化回收和储能传热领域之间的桥梁,同时包覆性强,与石蜡结合后得到的新型相变材料具有更好的热导率和更高的比表面积。(The invention discloses a preparation method of a waste plastic modified and shaped phase-change material heat storage working medium, which comprises the steps of classifying and crushing collected waste plastics, and then respectively washing and purifying the waste plastics by using alcohol to obtain cleaner waste plastics; putting clean waste plastic into a tube furnace for pyrolysis of the waste plastic, completely pyrolyzing the waste plastic into a carbon-rich hydrogen compound volatile substance precursor raw material, then performing carbon vapor deposition, then reinforcing a carbon skeleton, and finally naturally cooling to room temperature to obtain a porous carbon material; and melting paraffin, melting the molten paraffin into the porous carbon material by using a vacuum leaching method, completely absorbing the paraffin by the porous carbon material, taking out the porous carbon material, and drying under vacuum to obtain the shaped phase-change material heat storage working medium. In order to construct a bridge between the fields of high-value conversion recovery and energy storage and heat transfer of waste plastics, the coating property is strong, and the novel phase change material obtained after being combined with paraffin has better heat conductivity and higher specific surface area.)

1. A preparation method of a waste plastic modified and shaped phase-change material heat storage working medium is characterized by comprising the following steps:

(1) pretreatment of waste plastics: classifying and crushing the collected waste plastics, respectively washing and purifying the crushed waste plastics with alcohol, and washing off residual organic dirt on the waste plastics to obtain cleaner waste plastics;

(2) preparation of porous carbon material: weighing clean waste gas plastic, putting the plastic into a porcelain boat, putting the porcelain boat into a tube furnace, calcining the plastic to pyrolyze the waste plastic, completely pyrolyzing the waste plastic to obtain a carbon-rich volatile compound precursor raw material, performing carbon vapor deposition, reinforcing a carbon skeleton, and naturally cooling to room temperature to obtain a material, wherein the material is taken out to obtain a porous carbon material;

(3) preparing a heat storage working medium of the shaped phase-change material: melting paraffin at 80 ℃, melting the molten paraffin into the porous carbon material by using a vacuum leaching method, completely absorbing the paraffin by the porous carbon material, taking out the porous carbon material, and drying under vacuum to obtain the shaped phase-change material heat storage working medium.

2. The preparation method of the waste plastic modified and shaped phase-change material heat storage working medium according to claim 1, characterized by comprising the following steps: the waste plastics in the step (1) are classified into one or more of a mixture of polyethylene and polypropylene, polyvinyl chloride, butyronitrile, polyamide, polyphenyl ether, polyvinyl acetate, cellulose acetate, polyformaldehyde and polycarbonate.

3. The preparation method of the waste plastic modified and shaped phase-change material heat storage working medium according to claim 1, characterized by comprising the following steps: and (3) in the step (2), the waste plastic pyrolysis process is carried out at a heating rate of 10 ℃/min, and the temperature is increased from room temperature to 650 ℃ and is maintained for 30 minutes.

4. The preparation method of the waste plastic modified and shaped phase-change material heat storage working medium according to claim 1, characterized by comprising the following steps: the vapor deposition process in the step (2) is increased from 650 ℃ to 800 ℃ at a temperature increase rate of 5 ℃/min and maintained at the temperature for 30 minutes.

5. The preparation method of the waste plastic modified and shaped phase-change material heat storage working medium according to claim 1, characterized by comprising the following steps: in the step (2), the carbon skeleton reinforcing process is carried out at a temperature rise rate of 10 ℃/min from 800 ℃ to 900 ℃, and the temperature is maintained for 20 min.

6. The preparation method of the waste plastic modified and shaped phase-change material heat storage working medium according to claim 1, characterized by comprising the following steps: the phase transition temperature of the paraffin in the step (3) is 60 ℃.

7. The preparation method of the waste plastic modified and shaped phase-change material heat storage working medium according to claim 1, characterized by comprising the following steps: and (4) stirring by using a magnetic stirrer when the molten paraffin is melted into the porous carbon material in the step (3), wherein the stirring speed is 600rpm/min, and the stirring time is 1 hour.

8. The preparation method of the waste plastic modified and shaped phase-change material heat storage working medium according to claim 1, characterized by comprising the following steps: in the step (3), the vacuum drying temperature is 40-55 ℃, and the drying time is 8-15 hours.

Technical Field

The invention relates to the technical field of shaped phase-change materials, in particular to a preparation method of a waste plastic modified shaped phase-change material heat storage working medium.

Background

The heat transfer process relates to all industries in the industry. With the increasing heat load of the heat transfer system and the complication of the structure of the heat transfer system, higher requirements are put on heat transfer technologies, such as cooling of a heat-insulating superconductor, heat control in thin film deposition, heat management of a power battery, heat dissipation of a high-power electronic element, heat management of an aerospace plane and the like, and the improvement of the performance of a heat transfer medium is one of the main ways of enhancing heat transfer.

According to statistics, about ten million tons of waste plastics are generated globally, wherein less than 40% of China is recycled, the recycling rate of the waste plastics in Japan and northern Europe is about 72%, the recycling rate of the waste plastics in Korea is about 64%, and the recycling rate of the waste plastics in other countries and regions is only 10% -30%, the waste plastics are stable in chemical properties and difficult to degrade, and the waste plastics are converted into porous carbon materials with high value to be applied to the field of heat transfer and energy storage in order to solve the recycling problem of the waste plastics. The porous carbon material refers to a carbon material with different pore size structures, the pore size is generally between a nanometer grade micropore and a micron grade macropore, and the pore size generally depends on a precursor of the porous carbon material and a processing and preparation process flow thereof. The porous carbon material has the advantages of high chemical stability and good electrical property, and has the characteristics of high specific surface area, rich and partially adjustable pore structure, excellent adsorption performance and mechanical property and the like due to the existence of a loose porous structure, so that the porous carbon material is widely applied to the aspects of gas separation, water purification, chromatographic analysis, catalysis, electrochemical energy storage and the like. The invention aims to solve the problem of how to convert various waste plastics into porous carbon materials at a high value by using a high-temperature calcination method and apply the porous carbon materials to the field of energy storage and heat transfer, so that the obtained heat storage working medium has the advantages of changing waste into valuables, utilizing wastes and having a remarkable effect, and has wide raw material sources in the aspects of raw materials and manufacturing processes and easy popularization.

Disclosure of Invention

The invention aims to provide a preparation method of a waste plastic modified and shaped phase-change material heat storage working medium, which aims to form a bridge between the fields of waste plastic high-value conversion recovery and energy storage and heat transfer, has strong coating property, and has better heat conductivity and higher specific surface area compared with the traditional phase-change material after being combined with paraffin.

In order to achieve the aim, the invention provides a preparation method of a waste plastic modified and shaped phase-change material heat storage working medium, which comprises the following steps:

(1) pretreatment of waste plastics: classifying and crushing the collected waste plastics, respectively washing and purifying the crushed waste plastics with alcohol, and washing off residual organic dirt on the waste plastics to obtain cleaner waste plastics;

(2) preparation of porous carbon material: weighing clean waste gas plastic, putting the plastic into a porcelain boat, putting the porcelain boat into a tube furnace, calcining the plastic to pyrolyze the waste plastic, completely pyrolyzing the waste plastic to obtain a carbon-rich volatile compound precursor raw material, performing carbon vapor deposition, reinforcing a carbon skeleton, and naturally cooling to room temperature to obtain a material, wherein the material is taken out to obtain a porous carbon material;

(3) preparing a heat storage working medium of the shaped phase-change material: melting paraffin at 80 ℃, melting the molten paraffin into the porous carbon material by using a vacuum leaching method, completely absorbing the paraffin by the porous carbon material, taking out the porous carbon material, and drying under vacuum to obtain the shaped phase-change material heat storage working medium.

Preferably, the waste plastics in step (1) are classified into one or more of a mixture of polyethylene and polypropylene, polyvinyl chloride, butyronitrile, polyamide, polyphenylene oxide, polyvinyl acetate, cellulose acetate, polyformaldehyde and polycarbonate.

Preferably, the pyrolysis process of the waste plastics in the step (2) is carried out at a heating rate of 10 ℃/min from room temperature to 650 ℃ for 30 minutes.

Preferably, the vapor deposition process in step (2) is increased from 650 ℃ to 800 ℃ at a temperature increase rate of 5 ℃/min and maintained at the temperature for 30 minutes.

Preferably, the carbon skeleton reinforcing process in the step (2) is to increase the temperature from 800 ℃ to 900 ℃ at a temperature increasing rate of 10 ℃/min, and maintain the temperature for 20 min.

Preferably, the phase transition temperature of the paraffin wax in the step (3) is 60 ℃.

Preferably, when the paraffin wax melted in the step (3) is melted into the porous carbon material, a magnetic stirrer is used for stirring, the stirring speed is 600rpm/min, and the stirring time is 1 hour.

Preferably, the vacuum drying temperature in the step (3) is 40-55 ℃, and the drying time is 8-15 hours.

Therefore, according to the preparation method of the waste plastic modified and shaped phase change material heat storage working medium, in order to construct a bridge between the fields of waste plastic high-value conversion and recovery and energy storage and heat transfer, the wrapping property is strong, compared with the traditional phase change material, the novel phase change material obtained by combining the novel phase change material with paraffin has better heat conductivity and higher specific surface area, and the highest apparent area is increased to 1123m²g^-1The coating rate is more than 70%, the raw materials are wide in source, the manufacturing process is simple, and the coating has a good application prospect.

The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.

Drawings

FIG. 1 is a xrd test chart after calcination of polyvinyl acetate;

FIG. 2 is a graph of xrd test after cellulose acetate calcination;

FIG. 3 is a graph of xrd testing after polycarbonate calcination.

Detailed Description

The invention provides a preparation method of a waste plastic modified and shaped phase-change material heat storage working medium, which comprises the following steps:

(1) pretreatment of waste plastics: classifying and crushing the collected waste plastics, respectively washing and purifying the crushed waste plastics with alcohol, and washing off residual organic dirt on the waste plastics to obtain cleaner waste plastics;

(2) preparation of porous carbon material: weighing clean waste plastic, putting the weighed waste plastic into a porcelain boat, putting the porcelain boat into a tube furnace, calcining the waste plastic to pyrolyze the waste plastic, raising the temperature from room temperature to 650 ℃ at the heating rate of 10 ℃/min, maintaining the temperature for 30 minutes, completely pyrolyzing the waste plastic to obtain a volatile substance precursor raw material of a carbon-rich hydrogen compound, then performing vapor deposition of carbon, raising the temperature from 650 ℃ to 800 ℃ at the heating rate of 5 ℃/min, maintaining the temperature for 30 minutes, then reinforcing a carbon skeleton, raising the temperature from 800 ℃ to 900 ℃ at the heating rate of 10 ℃/min, maintaining the temperature for 20 minutes, and finally naturally cooling to room temperature and taking out the material to obtain the porous carbon material;

(3) preparing a heat storage working medium of the shaped phase-change material: melting paraffin (phase change temperature is 60 ℃) at 80 ℃, melting the melted paraffin into the porous carbon material by using a vacuum leaching method, stirring by using a magnetic stirrer at the stirring speed of 600rpm/min for 1 hour to ensure that the paraffin is completely absorbed by the porous carbon material, taking out the porous carbon material and drying under vacuum, wherein the vacuum drying temperature is 40-55 ℃, and the drying time is 8-15 hours, thus obtaining the heat storage working medium of the shaped phase change material.

The waste plastics used in the step (1) are classified into one or more of a mixture of polyethylene and polypropylene, polyvinyl chloride, butyronitrile, polyamide, polyphenyl ether, polyvinyl acetate, cellulose acetate, polyformaldehyde and polycarbonate.

The invention is described in further detail below with reference to the figures and specific examples.

The reagents and starting materials used in the following examples are all commercially available reagents unless otherwise specified.

Example 1

The phase change material is prepared by taking waste polyphenyl ether, paraffin and normal hexane as raw materials.

Simply crushing the classified waste polyphenyl ether plastics or by using a crusher, putting the crushed small polyphenyl ether plastics into a glass ware, simply soaking and washing the small polyphenyl ether plastics by using alcohol, cleaning organic reagents remained on the waste plastics, fishing out the polyphenyl ether plastics, and drying the polyphenyl ether plastics in a constant-temperature drying oven at 50 ℃ until the alcohol on the surface of the polyphenyl ether plastics is completely volatilized.

Taking 10g of pure polyphenyl ether, putting the pure polyphenyl ether into a porcelain boat, putting the porcelain boat into a high-temperature tube furnace, introducing nitrogen into the tube furnace at a flow rate of 60ml/s for 30min in advance, exhausting air in the tube furnace, starting a program for calcination, raising the temperature of the calcination process from room temperature to 650 ℃ at a heating rate of 10 ℃/min, maintaining the temperature for 30min to ensure that the purified waste plastic is completely pyrolyzed into a carbon-rich hydrogen compound volatile matter precursor raw material, raising the temperature to 800 ℃ at a heating rate of 5 ℃/min, maintaining the temperature for 30min at the same temperature to perform carbon vapor deposition, raising the temperature to 900 ℃ at a heating rate of 10 ℃/min, maintaining the temperature for 20min, treating the obtained porous carbon material in nitrogen at 900 ℃ to strengthen a carbon skeleton, naturally cooling to room temperature, taking out the material to obtain the porous carbon material, and weighing to obtain 1.2g of the porous carbon material.

The obtained porous carbon material is ground and tested in xrd, and the obtained carbon material basically meets the requirements by analyzing the position height information of diffraction peaks in a xrd figure.

The grinded porous carbon material 5g, paraffin 3g and n-hexane were put in a glass container with a rotor, the three substances were mixed and stirred for 1 hour at 80 ℃ and 600rpm/min with a magnetic stirrer, the stirred mixed solution was taken out, the n-hexane was evaporated out at 80 ℃ with a rotary evaporator, and finally the mixture was put in a vacuum drying oven and vacuum-adsorbed for 8 hours at 80 ℃.

Tests show that the coating rate of the phase-change material after being blended with the paraffin reaches 63 percent, the latent heat is 102J/g, and the heat conductivity coefficient is 0.56W/m.K.

Example 2

The phase change material is prepared by taking waste plastic bottles (polyethylene and polypropylene mixture), paraffin and normal hexane as raw materials.

Simply crushing the classified waste plastic bottles by using a crusher, putting the crushed small plastic bottles into a glass ware, simply soaking and washing the small plastic bottles by using alcohol, cleaning organic reagents remained on the waste plastic bottles, fishing out the plastic bottles, and drying the plastic bottles in a constant-temperature drying oven at 50 ℃ until the alcohol on the surfaces of the plastic bottles is completely volatilized.

Taking 10g of a pure plastic bottle, putting the plastic bottle into a porcelain boat, placing the porcelain boat into a high-temperature tube furnace, introducing nitrogen into the tube furnace at a flow rate of 60ml/s for 30min in advance, exhausting air in the tube furnace, starting a program for calcination, raising the temperature of the calcination process from room temperature to 650 ℃ at a heating rate of 10 ℃/min, maintaining the temperature for 30min to ensure that the purified waste plastic is completely pyrolyzed into a carbon-rich hydrogen compound volatile matter precursor raw material, raising the temperature to 800 ℃ at a heating rate of 5 ℃/min, maintaining the temperature for 30min at the same temperature to perform carbon vapor deposition, raising the temperature to 900 ℃ at a heating rate of 10 ℃/min, maintaining the temperature for 20min, and aiming at treating the obtained porous carbon material in nitrogen at 900 ℃ to strengthen a carbon skeleton, naturally cooling to room temperature, taking out the material to obtain the porous carbon material, and weighing to obtain 0.9g of the porous carbon material.

The obtained porous carbon material is ground and tested in xrd, and the obtained carbon material basically meets the requirements by analyzing the position height information of diffraction peaks in a xrd figure.

The grinded porous carbon material 5g, paraffin 3g and n-hexane were put in a glass container with a rotor, the three substances were mixed and stirred for 1 hour at 80 ℃ and 600rpm/min with a magnetic stirrer, the stirred mixed solution was taken out, the n-hexane was evaporated out at 80 ℃ with a rotary evaporator, and finally the mixture was put in a vacuum drying oven and vacuum-adsorbed for 8 hours at 80 ℃.

Tests show that the coating rate of the phase change material after being blended with the paraffin reaches 61%, the latent heat is 111J/g, and the heat conductivity coefficient is 0.45W/m.K.

Example 3

The phase-change material is prepared by taking waste polyvinyl chloride, paraffin and normal hexane as raw materials.

Simply crushing the classified waste polyvinyl chloride plastics by using a crusher, simply soaking and washing the crushed small polyvinyl chloride plastics in alcohol in a glass ware, cleaning organic reagents remained on the waste plastics, fishing out the polyvinyl chloride plastics, and drying in a constant-temperature drying oven at 50 ℃ until the alcohol on the surface of the polyvinyl chloride plastics is completely volatilized.

Taking 10g of pure polyvinyl chloride, putting the pure polyvinyl chloride into a porcelain boat, putting the porcelain boat into a high-temperature tube furnace, introducing nitrogen into the tube furnace at a flow rate of 60ml/s for 30min in advance, exhausting air in the tube furnace, starting a program for calcination, raising the temperature of the calcination process from room temperature to 650 ℃ at a heating rate of 10 ℃/min, maintaining the temperature for 30min to ensure that the purified waste plastic is completely pyrolyzed into a carbon-rich hydrogen compound volatile matter precursor raw material, raising the temperature to 800 ℃ at a heating rate of 5 ℃/min, maintaining the temperature for 30min at the same temperature to perform carbon vapor deposition, raising the temperature to 900 ℃ at a heating rate of 10 ℃/min, maintaining the temperature for 20min, aiming at treating the obtained porous carbon material in nitrogen at 900 ℃ to strengthen a carbon skeleton, naturally cooling to room temperature, taking out the material to obtain the porous carbon material, and weighing to obtain 1.1g of the porous carbon material.

The obtained porous carbon material is ground and tested in xrd, and the obtained carbon material basically meets the requirements by analyzing the position height information of diffraction peaks in a xrd figure.

The grinded porous carbon material 5g, paraffin 3g and n-hexane were put in a glass container with a rotor, the three substances were mixed and stirred for 1 hour at 80 ℃ and 600rpm/min with a magnetic stirrer, the stirred mixed solution was taken out, the n-hexane was evaporated out at 80 ℃ with a rotary evaporator, and finally the mixture was put in a vacuum drying oven and vacuum-adsorbed for 8 hours at 80 ℃.

Tests show that the coating rate of the phase change material after being blended with the paraffin reaches 59%, the latent heat is 108J/g, and the heat conductivity coefficient is 0.49W/m.K.

Example 4

The phase-change material is prepared by taking waste butyronitrile, paraffin and normal hexane as raw materials.

Simply crushing the classified waste butyronitrile by using a crusher, simply soaking and washing the crushed small butyronitrile in alcohol in a glass ware, cleaning the residual organic reagent on the waste plastic, fishing out the butyronitrile, and drying in a constant-temperature drying oven at 50 ℃ until the alcohol on the surface is completely volatilized.

10g of pure butyronitrile is taken out and put into a porcelain boat and is put into a high-temperature tube furnace, nitrogen is introduced into the tube furnace for 30min at the flow rate of 60ml/s in advance, air in the tube furnace is exhausted, the procedure calcination is started, the temperature of the calcination process is increased from room temperature to 650 ℃ at the temperature rise rate of 10 ℃/min for 30min to ensure that the purified waste plastic is completely pyrolyzed into a volatile matter precursor raw material of the hydrogen-rich carbon compound, then the temperature of the waste plastic is increased to 800 ℃ at the temperature rise rate of 5 ℃/min, carbon vapor deposition is carried out at the same temperature for 30min, finally the temperature of the waste plastic is increased to 900 ℃ at the temperature rise rate of 10 ℃/min for 20min, the aim is to treat the obtained porous carbon material in nitrogen at 900 ℃ to strengthen a carbon skeleton, finally the porous carbon material is naturally cooled to room temperature, the material is taken out, and the porous carbon material of 0.8g is obtained after weighing.

The obtained porous carbon material is ground and tested in xrd, and the obtained carbon material basically meets the requirements by analyzing the position height information of diffraction peaks in a xrd figure.

The grinded porous carbon material 5g, paraffin 3g and n-hexane were put in a glass container with a rotor, the three substances were mixed and stirred for 1 hour at 80 ℃ and 600rpm/min with a magnetic stirrer, the stirred mixed solution was taken out, the n-hexane was evaporated out at 80 ℃ with a rotary evaporator, and finally the mixture was put in a vacuum drying oven and vacuum-adsorbed for 8 hours at 80 ℃.

Tests show that the coating rate of the phase-change material after being blended with the paraffin reaches 57%, the latent heat is 103J/g, and the heat conductivity coefficient is 0.56W/m.K.

Example 5

The phase-change material is prepared by taking waste polyvinyl acetate, paraffin and normal hexane as raw materials.

Simply crushing the classified waste polyvinyl acetate plastics by using a crusher, simply soaking and washing the crushed small polyvinyl acetate plastics in alcohol in a glass ware, cleaning organic reagents remained on the waste plastics, fishing out the polyvinyl acetate plastics, and drying in a constant-temperature drying oven at 50 ℃ until the alcohol on the surface is completely volatilized.

Taking 10g of pure polyvinyl acetate, putting the pure polyvinyl acetate into a porcelain boat, placing the porcelain boat into a high-temperature tubular furnace, introducing nitrogen into the tubular furnace at a flow rate of 60ml/s for 30min in advance, exhausting air in the tubular furnace, starting a program for calcination, raising the temperature of the calcination process from room temperature to 650 ℃ at a temperature rise rate of 10 ℃/min, maintaining the temperature for 30min to ensure that the purified waste plastic is completely pyrolyzed into a carbon-rich hydrogen compound volatile matter precursor raw material, raising the temperature to 800 ℃ at a temperature rise rate of 5 ℃/min, maintaining the temperature for 30min to perform carbon vapor deposition, raising the temperature to 900 ℃ at a temperature rise rate of 10 ℃/min, maintaining the temperature for 20min, and aiming at treating the obtained porous carbon material in nitrogen at 900 ℃ to strengthen a carbon skeleton, naturally cooling to room temperature, taking out the material to obtain the porous carbon material, and weighing the porous carbon material to obtain 1.4 g.

The obtained porous carbon material is ground and tested by xrd as shown in fig. 1, and the carbon material prepared by analyzing the position height information of diffraction peaks in xrd figure is basically in accordance with the requirements.

The grinded porous carbon material 5g, paraffin 3g and n-hexane were put in a glass container with a rotor, the three substances were mixed and stirred for 1 hour at 80 ℃ and 600rpm/min with a magnetic stirrer, the stirred mixed solution was taken out, the n-hexane was evaporated out at 80 ℃ with a rotary evaporator, and finally the mixture was put in a vacuum drying oven and vacuum-adsorbed for 8 hours at 80 ℃.

Tests show that the coating rate of the phase-change material after being blended with the paraffin reaches 65%, the latent heat is 112J/g, and the heat conductivity coefficient is 0.51W/m.K.

Example 6

The phase-change material is prepared by taking waste polyamide, paraffin and normal hexane as raw materials.

Simply crushing the classified waste polyamide plastics by using a crusher, simply soaking and washing the crushed small polyamide plastics in alcohol in a glass ware, cleaning organic reagents remained on the waste plastics, fishing out the polyamide plastics, and drying in a constant-temperature drying oven at 50 ℃ until the alcohol on the surface of the polyamide plastics is completely volatilized.

Taking 10g of pure polyamide, putting the polyamide into a porcelain boat, putting the porcelain boat into a high-temperature tube furnace, introducing nitrogen into the tube furnace at a flow rate of 60ml/s for 30min in advance, exhausting air in the tube furnace, starting a program for calcination, raising the temperature of the calcination process from room temperature to 650 ℃ at a heating rate of 10 ℃/min, maintaining the temperature for 30min to completely pyrolyze the purified waste plastic into a carbon-rich hydrogen compound volatile matter precursor raw material, raising the temperature to 800 ℃ at a heating rate of 5 ℃/min, maintaining the temperature for 30min to perform carbon vapor deposition, raising the temperature to 900 ℃ at a heating rate of 10 ℃/min, maintaining the temperature for 20min, and aiming at treating the obtained porous carbon material in nitrogen at 900 ℃ to strengthen a carbon skeleton, naturally cooling to room temperature, taking out the material to obtain the porous carbon material, and weighing to obtain 1.2g of the porous carbon material.

The obtained porous carbon material is ground and tested in xrd, and the obtained carbon material basically meets the requirements by analyzing the position height information of diffraction peaks in a xrd figure.

The grinded porous carbon material 5g, paraffin 3g and n-hexane were put in a glass container with a rotor, the three substances were mixed and stirred for 1 hour at 80 ℃ and 600rpm/min with a magnetic stirrer, the stirred mixed solution was taken out, the n-hexane was evaporated out at 80 ℃ with a rotary evaporator, and finally the mixture was put in a vacuum drying oven and vacuum-adsorbed for 8 hours at 80 ℃.

Tests show that the coating rate of the phase-change material after being blended with the paraffin reaches 64 percent, the latent heat is 108J/g, and the heat conductivity coefficient is 0.49W/m.K.

Example 7

The phase-change material is prepared by taking waste cellulose acetate, paraffin and normal hexane as raw materials.

Simply crushing the classified waste cellulose acetate plastics by using a crusher, putting the crushed small pieces of cellulose acetate plastics into a glass ware, simply soaking and washing the small pieces of cellulose acetate plastics by using alcohol, cleaning organic reagents remained on the waste plastics, fishing out the cellulose acetate plastics, and drying the cellulose acetate plastics in a constant-temperature drying oven at 50 ℃ until the alcohol on the surface of the waste plastics is completely volatilized.

Taking 10g of pure cellulose acetate, placing the pure cellulose acetate into a porcelain boat, placing the porcelain boat into a high-temperature tube furnace, introducing nitrogen into the tube furnace at a flow rate of 60ml/s for 30min in advance, exhausting air in the tube furnace, starting a program for calcination, raising the temperature of the calcination process from room temperature to 650 ℃ at a temperature rise rate of 10 ℃/min, maintaining the temperature for 30min to ensure that the purified waste plastic is completely pyrolyzed into a carbon-rich hydrogen compound volatile matter precursor raw material, raising the temperature to 800 ℃ at a temperature rise rate of 5 ℃/min, maintaining the temperature at the same temperature for 30min to perform carbon vapor deposition, raising the temperature to 900 ℃ at a temperature rise rate of 10 ℃/min, maintaining the temperature for 20min, and aiming at treating the obtained porous carbon material in nitrogen at 900 ℃ to strengthen a carbon skeleton, naturally cooling to room temperature, taking out the material to obtain the porous carbon material, and weighing the porous carbon material to obtain 1.4 g.

The obtained porous carbon material is ground and tested by xrd as shown in fig. 2, and the carbon material prepared by analyzing the position height information of the diffraction peak in xrd figure is basically in accordance with the requirement.

The grinded porous carbon material 5g, the grinded paraffin wax 3g and the n-hexane are put into a glass container with a rotor, the three substances are mixed and stirred for 1h by a magnetic stirrer under the conditions of 80 ℃ and 600rpm/min, the stirred mixed liquid is taken out, the n-hexane is evaporated completely by a rotary evaporator under the temperature of 80 ℃, and finally the mixed liquid is put into a vacuum drying oven to be vacuum-absorbed for 8 h under the condition of 80 ℃.

Tests show that the coating rate of the phase change material after being blended with the paraffin reaches 60%, the latent heat is 101J/g, and the heat conductivity coefficient is 0.52W/m.K.

Example 8

The phase-change material is prepared by taking waste polycarbonate, paraffin and normal hexane as raw materials.

Simply crushing the classified waste polycarbonate plastics by using a crusher, putting the crushed small blocks of polycarbonate plastics into a glass ware, simply soaking and washing the small blocks of polycarbonate plastics by using alcohol, cleaning organic reagents remained on the waste plastics, fishing out the polycarbonate plastics, and drying the polycarbonate plastics in a constant-temperature drying oven at 50 ℃ until the alcohol on the surface of the waste plastics is completely volatilized.

Taking 10g of pure polycarbonate, placing the pure polycarbonate into a porcelain boat, placing the porcelain boat in a high-temperature tube furnace, introducing nitrogen into the tube furnace at a flow rate of 60ml/s for 30min in advance, exhausting air in the tube furnace, starting a program for calcination, raising the temperature of the calcination process from room temperature to 650 ℃ at a temperature rise rate of 10 ℃/min, maintaining the temperature for 30min to ensure that the purified waste plastic is completely pyrolyzed into a carbon-rich hydrogen compound volatile matter precursor raw material, then raising the temperature to 800 ℃ at a temperature rise rate of 5 ℃/min, maintaining the temperature for 30min to perform carbon vapor deposition, finally raising the temperature to 900 ℃ at a temperature rise rate of 10 ℃/min, maintaining the temperature for 20min, and aiming at treating the obtained porous carbon material in nitrogen at 900 ℃ to strengthen a carbon skeleton, and finally naturally cooling to room temperature, taking out the material to obtain the porous carbon material, and weighing the porous carbon material to obtain 1.2 g.

The obtained porous carbon material is ground and tested by xrd as shown in fig. 3, and the carbon material prepared by analyzing the position height information of the diffraction peak in xrd figure is basically in accordance with the requirement.

The grinded porous carbon material 5g, paraffin 3g and n-hexane were put in a glass container with a rotor, the three substances were mixed and stirred for 1 hour at 80 ℃ and 600rpm/min with a magnetic stirrer, the stirred mixed solution was taken out, the n-hexane was evaporated out at 80 ℃ with a rotary evaporator, and finally the mixture was put in a vacuum drying oven and vacuum-adsorbed for 8 hours at 80 ℃.

Tests show that the coating rate of the phase-change material after being blended with the paraffin reaches 58%, the latent heat is 112J/g, and the heat conductivity coefficient is 0.46W/m.K.

Therefore, according to the preparation method of the waste plastic modified and shaped phase change material heat storage working medium, a bridge between the fields of waste plastic high-value conversion recovery and energy storage and heat transfer is constructed, meanwhile, the wrapping property is strong, and compared with the traditional phase change material, the novel phase change material obtained by combining the novel phase change material with paraffin has better heat conductivity and higher specific surface area.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the invention without departing from the spirit and scope of the invention.