阅读说明：本技术 一种废弃聚合物衍生炭及其制备方法和应用 (Waste polymer derived carbon and preparation method and application thereof ) 是由 吴丁财 唐友臣 刘绍鸿 岑宗恒 卢焰 于 2021-06-25 设计创作，主要内容包括：本发明涉及材料技术领域,提供了一种废弃聚合物衍生炭及其制备方法和应用,将废弃聚合物粉碎后和硫粉进行混合,得到混合粉料；将所述混合粉料在惰性气体中程序升温炭化,得到废弃聚合物衍生炭。该方法以来源丰富、价格低廉的废弃聚合物和硫粉为原料,通过简单的热处理,实现了废弃聚合物向高附加值清洁能源材料的升级回收,且制备工艺简单、适于大规模生产,具有超高的商业和社会实用价值。采用上述方法制备得到的废弃聚合物衍生炭具有极高且可调的硫原子含量,石墨微晶层间距扩宽至0.41nm,是一类优异的钠/钾离子电池负极材料。(The invention relates to the technical field of materials, and provides a waste polymer derived carbon and a preparation method and application thereof, wherein waste polymer is crushed and then mixed with sulfur powder to obtain mixed powder; and (3) carrying out temperature-programmed carbonization on the mixed powder in inert gas to obtain the waste polymer derived carbon. The method takes the waste polymer and the sulfur powder which are rich in sources and low in price as raw materials, realizes the upgrading and recovery of the waste polymer to the clean energy material with high added value through simple heat treatment, has simple preparation process, is suitable for large-scale production, and has ultrahigh commercial and social practical values. The waste polymer derived carbon prepared by the method has extremely high and adjustable sulfur atom content, and the graphite microcrystal interlayer spacing is widened to 0.41nm, so that the carbon is an excellent sodium/potassium ion battery cathode material.)

1. A preparation method of waste polymer derived carbon is characterized by comprising the following steps: crushing the waste polymer and mixing the crushed waste polymer with sulfur powder to obtain mixed powder; and (3) carrying out temperature-programmed carbonization on the mixed powder in inert gas to obtain the waste polymer derived carbon.

2. The method according to claim 1, wherein the waste polymer is one or more of high density polyethylene, low density polyethylene, polypropylene, polystyrene, polyvinyl chloride, and polyethylene terephthalate plastic waste.

3. The method according to claim 2, wherein the mass ratio of the waste polymer to the sulfur powder is 1: 0.5-8.

4. The method according to claim 3, wherein the mass ratio of the waste polymer to the sulfur powder is 1: 2-4.

5. The method according to claim 1, 2, 3 or 4, wherein the temperature programming is divided into two stages, the first stage temperature is 200-350 ℃, and the holding time is 0.5-8 h; the temperature of the second section is 400-800 ℃, and the heat preservation time is 0.5-6 h.

6. The method according to claim 5, wherein the programmed temperature is 280 ± 50 ℃ for the first period, and the holding time for the first period is 1-4 h; the temperature of the second section of the programmed heating is 600-700 ℃, and the heat preservation time of the second section is 1-3 h.

7. The method according to claim 6, wherein the temperature programming rate is 2-5 ℃ min^-1(ii) a The particle size of the crushed waste polymer is 0.1-2 mm.

8. The method according to claim 7, wherein the inert gas is one or more of nitrogen, argon and helium, and the gas flow rate of the inert gas is 200-600 mL min^-1。

9. A waste polymer-derived carbon produced by the method of any one of claims 1 to 8.

10. Use of the waste polymer-derived carbon of claim 9 in a secondary rechargeable battery.

Technical Field

The invention relates to the technical field of materials, in particular to a method for efficiently carbonizing waste polymers assisted by vulcanization and application of the method in a secondary rechargeable battery.

Background

Plastics are irreplaceable in today's production and life due to their unique performance and price advantages. It is expected that in 2040, global plastic production will reach 8 billion tons per year, most of which will be discarded after a short life cycle. The disposal of plastic wastes is usually landfill and incineration, which not only brings serious environmental problems, but also causes huge waste of non-renewable resources. At present, physical recovery and chemical recovery are concerned, however, most of the physical recovery is degraded recovery, the performance of the recycled plastic is poor, the value is low, and the cost of the processes of recovery, classification, treatment and the like cannot be sufficiently compensated; high value-added chemicals such as gas, liquid and solid can be obtained through chemical recovery, upgrading recovery is expected to be achieved, but a large amount of catalysts are usually needed, conditions are harsh, recovery cost, application range and the like are not satisfactory, and the method is commercially unattractive. Therefore, the development of a simple and efficient recovery mode and the realization of high-valued utilization of the recovery mode are of great significance.

With the increasingly prominent energy crisis and environmental problems, the establishment of efficient, economical and pollution-free energy storage and conversion systems is urgent. Among them, sodium/potassium ion batteries are currently popular energy storage devices due to their advantages of low material cost, high safety, and the like. However, high performance electrode materials remain one of the key material bottlenecks toward commercialization. The method realizes upgrading and recycling of the waste polymer to the cathode material of the sodium/potassium ion battery by using a simple vulcanization crosslinking strategy, and has great practical value.

Disclosure of Invention

The invention aims to overcome the defects in the prior art, and the waste polymer is upgraded and recycled by vulcanization crosslinking to obtain the high-sulfur-content doped waste polymer derived carbon. The waste polymer derived carbon has extremely high and adjustable sulfur atom content, and the graphite microcrystal interlayer spacing is widened to 0.41nm, so that the waste polymer derived carbon is an excellent sodium/potassium ion battery cathode material. The waste polymer derived carbon takes waste polymers with rich sources and low price and sulfur powder as raw materials, realizes the upgrading and recovery of the waste polymers to clean energy materials with high added value through simple heat treatment, has simple preparation process, is suitable for large-scale production, and has ultrahigh commercial and social practical values.

In order to achieve the purpose, the invention provides the following technical scheme:

in a first aspect, the present invention provides a method for preparing waste polymer-derived carbon, comprising the steps of: crushing the waste polymer and mixing the crushed waste polymer with sulfur powder to obtain mixed powder; and (3) carrying out temperature-programmed carbonization on the mixed powder in inert gas to obtain the waste polymer derived carbon.

Preferably, the waste polymer is one or more of plastic wastes made of High Density Polyethylene (HDPE), Low Density Polyethylene (LDPE), polypropylene (PP), Polystyrene (PS), polyvinyl chloride (PVC) and polyethylene terephthalate (PET).

Preferably, the mass ratio of the waste polymer to the sulfur powder is 1: 0.5-8.

Preferably, the mass ratio of the waste polymer to the sulfur powder is 1: 2-4.

Preferably, the particle size of the crushed waste polymer is 0.1-2 mm.

Preferably, the temperature programming is divided into two stages, the temperature of the first stage is 200-350 ℃, and the heat preservation time is 0.5-8 h; the temperature of the second section is 400-.

Preferably, the temperature of the first section of programmed heating is 280 +/-50 ℃, and the time of the first section of heat preservation is 1-4 h.

Preferably, the temperature of the second section of the programmed heating is 600-700 ℃, and the heat preservation time of the second section is 1-3 h.

Preferably, the temperature programming rate is 2-5 ℃ min^-1。

Preferably, the inert gas is one or more of nitrogen, argon and helium, and the gas flow rate of the inert gas is 200～600mL min^-1。

In a second aspect, the present invention provides a waste polymer-derived carbon produced by the method for producing a waste polymer-derived carbon according to the first aspect.

In a third aspect, the invention provides the use of the waste polymer-derived carbon in a secondary rechargeable battery.

Preferably, the invention provides application of the waste polymer derived carbon as a negative electrode material of a sodium ion and potassium ion secondary battery.

The principle of the invention is as follows: in the heat treatment process, elemental sulfur opens rings to form sulfur free radicals, attacks C-H bonds of the waste polymers, removes hydrogen sulfide, crosslinks polymer chains, and effectively limits escape of hydrocarbon micromolecules along with further increase of temperature, so that efficient carbon formation of the waste polymers is realized; the doping of high-content sulfur atoms introduces rich active energy storage sites and widens the interlayer spacing of graphite microcrystals, is beneficial to the storage of sodium/potassium ions, and is an excellent cathode material of a sodium/potassium ion secondary battery.

The invention has the following beneficial effects:

(1) the sulfur content of the waste polymer derived carbon prepared by the method is extremely high and adjustable (the highest content can reach 40 wt%), and the interlayer spacing of graphite microcrystals is as wide as 0.41 nm.

(2) The invention uses cheap industrial raw material sulfur powder as a cross-linking agent, can realize the nondifferential high-efficiency carbon formation (the carbon atom conversion rate is up to 80%) of various waste polymers by only one-step heat treatment under normal pressure, has cheap raw materials and simple preparation process, and is beneficial to low-cost and large-scale preparation.

(3) The sulfur powder not only assists in efficient carbonization, but also serves as a dopant, and after carbonization, rich active energy storage sites are introduced, the graphite microcrystal interlayer spacing is widened, sodium/potassium storage is facilitated, the sulfur powder is an excellent cathode material of a sodium/potassium ion secondary battery, and the practical application value of the carbon material is greatly improved.

(4) The invention realizes the upgrading and recycling of waste polymers to high-added-value clean energy materials, changes waste into valuable and has ultrahigh commercial and social practical values.

Drawings

FIG. 1 is a SEM of waste polymer-derived carbon prepared in example 8 of the present invention.

FIG. 2 is a high resolution transmission photograph of waste polymer-derived carbon eight prepared in example 8 of the present invention.

FIG. 3 is a SEM of the waste polymer-derived carbon seventeen prepared in example 17 of the present invention.

FIG. 4 is a SEM of the used polymer-derived carbon prepared in example 18 of the present invention.

FIG. 5 is a SEM of the carbon nineteen derived from waste polymer prepared in example 19 of the present invention.

FIG. 6 is a scanning electron micrograph of spent polymer-derived carbon twenty prepared in example 20 of the present invention.

FIG. 7 is a SEM of twenty-one waste polymer-derived carbon prepared in example 21 of the present invention.

FIG. 8 is a graph of sodium rate performance of waste polymer-derived carbon prepared in examples 8, 17 and 18 of the present invention.

FIG. 9 shows the sodium electrical cycle performance of waste polymer-derived carbon prepared in examples 8, 17 and 18 of the present invention.

Detailed Description

The technical solutions of the present invention are further described in detail below with reference to the drawings and examples, and it should be noted that the description of the embodiments is provided to help understanding of the present invention, but the present invention is not limited thereto.

Example 1

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1:0.5, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept for 4 hours, the temperature is raised toHeating to 600 deg.C and maintaining for 3 hr; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon I.

Example 2

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1: 1, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept for 4 hours, the temperature is raised to 600 ℃ and is kept for 3 hours; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon II.

Example 3

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1:2, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept for 4 hours, the temperature is raised to 600 ℃ and is kept for 3 hours; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon III.

Example 4

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept for 4 hours, the temperature is raised to 600 ℃ and is kept for 3 hours; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon IV.

Example 5

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1: 8, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept for 4 hours, the temperature is raised to 600 ℃ and is kept for 3 hours; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon five.

Comparative example 1

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules;

(2) placing the granules prepared in the step (1) in 400mL min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the heating rate and is kept for 4h, the temperature is continuously raised to 600 ℃ and is kept for 3h, and the temperature is naturally reduced to the room temperature and then taken out.

Effect example 1

To further illustrate the advantageous effects of the present invention, the carbonization yields of the waste polymer-derived carbons prepared in examples 1 to 5 and comparative example 1 were counted, and the results are shown in table 1.

TABLE 1 carbonization yield of waste polymer-derived carbon from different feed ratios

	Mass ratio of sulfur powder to waste polymer	Carbonization yield (%)
			Example 1	0.5	16
Example 2	1	28
			Example 3	2	71
Example 4	4	106
			Example 5	8	144
Comparative example 1	0	0

The results show that: the difference between examples 1-5 is that the mass ratio of the waste polymer to the sulfur powder is different, and the higher the sulfur powder ratio is, the higher the carbonization yield of the waste polymer is. In comparative example 1, sulfur powder was not mixed, the carbonization yield was 0, and the waste polymer was not carbonized.

Example 6

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept at the temperature for 4 hours, the temperature is raised to 400 ℃ continuously and is kept at the temperature for 3 hours; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon six.

Example 7

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept at the temperature for 4 hours, the temperature is raised to 500 ℃ and kept at the temperature for 3 hours; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon seven.

Example 8

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept at the temperature for 4h, the temperature is raised to 700 ℃ and kept at the temperature for 3 h; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon eight.

Example 9

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1: 4, mixing to obtain mixed powder;

(2) mixing the mixture prepared in the step (1)Placing the mixed powder in a container for 400mL min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept at the temperature for 4 hours, the temperature is raised to 800 ℃ and kept at the temperature for 3 hours; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon nine.

Effect example 2

To further illustrate the beneficial effects of the present invention, the elemental content of the waste polymer-derived carbon prepared in examples 1, 6-9 was tested, and the carbon atom retention was calculated by combining the carbonization yield statistics, with the results shown in table 2.

TABLE 2 carbon atom retention of waste polymer-derived carbons at different carbonization temperatures

The results show that: the difference between examples 1 and 6-9 is that the temperature in the second stage of temperature programming is different, and the carbonization yield, sulfur atom content and carbon atom retention rate of the obtained waste polymer-derived carbon gradually decrease with the increase of the temperature.

Example 10

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 200 ℃ at the temperature raising rate and is kept for 4 hours, the temperature is raised to 700 ℃ and kept for 3 hours; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon.

Example 11

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 350 ℃ at the temperature raising rate and is kept for 4 hours, the temperature is raised to 700 ℃ continuously and is kept for 3 hours; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon eleven.

Example 12

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept for 1h, the temperature is raised to 700 ℃ and is kept for 3 h; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon twelve.

Example 13

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept at the temperature for 2h, the temperature is raised to 700 ℃ and kept at the temperature for 3 h; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon thirteen.

Example 14

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1: 4, mixing to obtain mixed powder;

(2) mixing the mixture prepared in the step (1)Placing the powder in a container for 400mL min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept for 4 hours, the temperature is raised to 700 ℃ and is kept for 1 hour; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon fourteen.

Example 15

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of HDPE, cutting the plastic garbage into small pieces after cleaning, and mechanically crushing the small pieces into granules; HDPE granules and sulfur powder are mixed according to the mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept for 4 hours, the temperature is raised to 700 ℃ and kept for 6 hours; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon fifteen.

Effect example 3

To further illustrate the beneficial effects of the present invention, statistics were made on the carbonization yields of the waste polymer-derived carbons prepared in examples 8, 10-15, and the results are shown in Table 3.

TABLE 3 carbonization yield of waste Polymer derived carbon for different carbonization conditions

The results show that: the carbonization yield is increased and then decreased along with the increase of the temperature of the first section of the temperature rise of the program; the influence of the first period of heat preservation time of programmed heating on the carbonization yield is little; the second stage of heat preservation time has larger influence on the carbonization yield, and the carbonization yield is reduced along with the extension of the heat preservation time.

Example 16

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of low-density polyethylene (LDPE), cleaning, cutting into small pieces, and mechanically pulverizing into granules; mixing LDPE pellets and sulfur powder according to a mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept at the temperature for 4h, the temperature is raised to 700 ℃ and kept at the temperature for 3 h; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon sixteen.

Example 17

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of polypropylene (PP), cleaning, cutting into small pieces, and mechanically crushing into granules; and (3) mixing PP granules and sulfur powder according to a mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept at the temperature for 4h, the temperature is raised to 700 ℃ and kept at the temperature for 3 h; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon seventeen.

Example 18

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of Polystyrene (PS), cleaning, cutting into small pieces, and mechanically crushing into granules; PS granules and sulfur powder are mixed according to the mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept at the temperature for 4h, the temperature is raised to 700 ℃ and kept at the temperature for 3 h; naturally cooling to room temperature, and taking out to obtain the waste polymer derived carbon eighteen.

Example 19

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of polyvinyl chloride (PVC), cleaning, cutting into small pieces, and mechanically crushing into granules; mixing LDPE pellets and sulfur powder according to a mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept at the temperature for 4h, the temperature is raised to 700 ℃ and kept at the temperature for 3 h; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon nineteen.

Example 20

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage made of polyethylene terephthalate (PET), cleaning, cutting into small pieces, and mechanically pulverizing into granules; PET granules and sulfur powder are mixed according to the mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept at the temperature for 4h, the temperature is raised to 700 ℃ and kept at the temperature for 3 h; naturally cooling to room temperature, and taking out to obtain the waste polymer derived carbon twenty.

Example 21

A preparation method of waste polymer derived carbon comprises the following steps:

(1) collecting plastic garbage of different materials, such as HDPE, LDPE, PP, PS, PVC, PET, cleaning, cutting into small pieces, and mechanically pulverizing into granules; mixing the waste mixture granules and sulfur powder according to a mass ratio of 1: 4, mixing to obtain mixed powder;

(2) putting the mixed powder prepared in the step (1) into 400mL of a container for min^-1Under nitrogen atmosphere at flow rate, at 5 deg.C for min^-1After the temperature is raised to 280 ℃ at the temperature raising rate and is kept at the temperature for 4h, the temperature is raised to 700 ℃ and kept at the temperature for 3 h; naturally cooling to room temperature and taking out to obtain the waste polymer derived carbon twenty-one.

Effect example 4

To further illustrate the beneficial effects of the present invention, the elemental content of the waste polymer-derived carbon prepared in examples 8, 16-21 was tested and the carbon atom retention was calculated in combination with the carbonization yield statistics, with the results shown in Table 4.

TABLE 4 carbonization yield and carbon atom retention for different waste polymer-derived carbons

The results show that: the difference between examples 8 and 16-21 is that the waste polymers are different in types, and it can be found that the PET plastic waste used in example 20 has a slightly low carbon atom retention rate, and other olefin polymers all have a high carbon atom retention rate, and have high carbonization efficiency and universality.

Application examples

The waste polymer-derived carbon obtained from examples 8, 17, 18 was ground to homogeneity and sieved through a 300 mesh screen, then mixed with a polyvinylidene fluoride binder and conductive carbon black in a ratio of 8: 1: 1 in a mass ratio; adding a proper amount of polyvinylpyrrolidone, and grinding to form slurry; and coating the uniformly ground slurry on a current collector aluminum foil, drying at 60 ℃ in vacuum, and cutting out an electrode plate with the diameter of 11 mm.

The electrode sheet was transferred to an argon atmosphere glove box, and a CR2032 button cell was assembled using a metal sodium sheet as a counter electrode and a 1M sodium perchlorate (ethylene carbonate) solution as an electrolyte. And testing the specific capacity and the cycling stability under different current densities in a voltage range of 0.01-3V by using a constant-current charge-discharge mode. The test results are shown in fig. 8 and 9. The material shows excellent rate performance and cycling stability. Taking the waste polymer derived carbon eight as an example, when the current density is from 0.1A g-¹Continuously increased to 0.2, 0.5, 1, 2, 3, 5 and 10A g^-1When the discharge capacity is 553, 506, 450, 411, 374, 352, 320 and 289mAh g, respectively^-1When the current density returns to 0.1A g^-1The specific capacity is correspondingly increased back to the original value. In addition, at 5 and 10A g^-1Under the current density, 3000 cycles of continuous charge and discharge have almost no attenuation of specific capacity.