Preparation method of internally supported waste asphalt loofah cross-linked derived carbon as battery negative electrode material

Abstract

The invention discloses a preparation method of an internally supported waste asphalt loofah cross-linked derived carbon as a battery negative electrode material, comprising: washing the waste asphalt mixture with clean water and drying; adding the waste asphalt mixture into a solvent for oil-stone separation; washing the loofah with an acidic solution or an alkaline solution, or with an acidic and alkaline solution in sequence, and vacuum drying; grinding the dried loofah, adding it to the separated waste asphalt solution, magnetic stirring, and heat preservation; raising the temperature until the solvent is completely volatilized to obtain a composite precursor of waste asphalt and loofah; high-temperature carbonizing the composite precursor of waste asphalt and loofah in a tubular furnace at a temperature of 600°C to 1600°C, the carbonization time is 1h to 4h, and cooling to room temperature to obtain a carbonized negative electrode material of waste asphalt and loofah. The invention obtains a lithium / sodium / potassium ion battery negative electrode material with excellent electrochemical performance, turning waste asphalt and loofah into treasure.

Description

Technical Field

[0001] The invention belongs to the technical field of ion battery material preparation, and relates to a method for preparing an internally supported waste asphalt loofah sponge cross-linked derived carbon as a battery negative electrode material. Background Art

[0002] my country produces 200 million tons of waste asphalt mixture every year, but its recycling rate is low. The accumulation of waste has caused serious waste of resources and damage to the ecological environment. At present, in the field of transportation, a small amount of waste asphalt mixture is generally added to the new mixture to achieve a certain degree of recycling. However, adding a low amount of waste asphalt mixture cannot solve the growing problem of recycled materials, resulting in unclear reuse benefits.

[0003] If waste asphalt can be converted into high-value-added electrode materials, it can greatly promote the recycling of waste asphalt mixtures. However, the cross-linking polymerization of waste asphalt is different from that of conventional new asphalt. At the same time, waste asphalt will show a higher degree of order when carbonized at high temperature, and the interlayer spacing is smaller, which is not conducive to the storage of lithium / sodium / potassium ions.

[0004] A Chinese patent with publication number CN 113213453 A discloses a method for preparing an ion battery negative electrode material based on waste asphalt. The template used is an inorganic salt or metal oxide, etc., which produces holes in the waste asphalt under high-temperature carbonization. The process is mostly physical pore-making, and does not undergo excessive cross-linking reactions with the waste asphalt itself, nor does it participate in the formation of the carbon skeleton of the final product. After the holes are formed, the template needs to be washed away. The production process is complicated and the template is difficult to recover, resulting in high costs. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a method for preparing an internally supported waste asphalt loofah sponge cross-linked derived carbon as a battery negative electrode material, thereby obtaining a lithium / sodium / potassium ion battery negative electrode material with excellent electrochemical properties, turning waste asphalt and loofah sponge into treasure, and solving the problems existing in the prior art.

[0006] The technical solution adopted by the present invention is a method for preparing an internally supported waste asphalt loofah cross-linked derived carbon as a battery negative electrode material, comprising the following steps:

[0007] S1: Wash the waste asphalt mixture with clean water and dry it;

[0008] S2: adding the waste asphalt mixture into a solvent to separate the oil and stone, and the separated waste asphalt solution is used for later use;

[0009] S3: washing the sponge gourd with an acidic solution or an alkaline solution, or with an acidic solution and an alkaline solution in sequence, and vacuum drying the sponge gourd after washing;

[0010] S4: Grind the dried loofah into powder, add it to the separated waste asphalt solution, stir it with magnetic force at 25℃~100℃, and keep it warm for 2h~12h;

[0011] S5: raising the magnetic stirring temperature to 100°C-150°C until the solvent is completely volatilized to obtain a composite precursor of waste asphalt and loofah sponge;

[0012] S6: The waste asphalt and loofah sponge composite precursor is carbonized at a temperature of 600°C to 1600°C in a tubular furnace for 1 h to 4 h. After cooling to room temperature, the carbonized negative electrode material of the waste asphalt and loofah sponge is obtained.

[0013] Furthermore, in S2, the solvent is a polar solvent, a non-polar solvent, or a mixed solvent of a polar solvent and a non-polar solvent.

[0014] Furthermore, in S2, the solvent is any one or more of carbon tetrachloride, dichloromethane, chloroform, 1,1,1-trichloroethane, trichloroethylene, 1-bromopropane, chlorobenzene, nitrobenzene, tetrahydrofuran, ethyl acetate, xylene, toluene, benzene, tetralin, methylcyclopentane, cyclohexane, n-pentane, n-hexane or decahydronaphthalene.

[0015] Furthermore, in S2, the solvent is a mixture of benzene and tetrahydrofuran in a ratio of 1 to 3:1.

[0016] Furthermore, in S3, the acidic solution is any one or more of sulfuric acid, hydrochloric acid, nitric acid, acetic acid, carbonic acid or aqua regia mixed in any proportion.

[0017] Furthermore, in S3, the alkaline solution is any one or more of ammonia water, sodium hydroxide, calcium hydroxide or potassium hydroxide mixed in any proportion.

[0018] Furthermore, in S6, the heating rate of high temperature carbonization is 1°C / min to 10°C / min.

[0019] Furthermore, in S6, the high temperature pyrolysis atmosphere is: any one of nitrogen or argon or a mixture of the two in any ratio.

[0020] Furthermore, it also includes: washing the waste asphalt prepared by S6 and the carbonized negative electrode material of loofah at 40-50°C with sulfuric acid solution and sodium hydroxide solution in turn for 2-3 hours by stirring, or washing with ethanol solution by ultrasonic for 2-3 hours, washing with ultrapure water and filtering until neutral after cleaning; and then drying in a vacuum oven.

[0021] Furthermore, before S6, the sample is pre-carbonized at 200-400°C, and the pre-carbonized sample is cleaned with sulfuric acid, and then washed with ultrapure water and filtered until neutral.

[0022] The beneficial effects of the present invention are:

[0023] 1. The present invention uses waste asphalt and loofah as carbon sources, and prepares ion battery negative electrode materials through appropriate pretreatment, compounding, and high-temperature carbonization. The negative electrode material can be applied to lithium / sodium / potassium ion batteries.

[0024] 2. Compared with the traditional waste asphalt treatment method, the present invention enables waste asphalt to achieve high added value utilization, and improves the specific capacity and first coulomb efficiency of waste asphalt in alkali metal ion batteries, providing a new solution for the reuse of waste asphalt.

[0025] 3. Compared with the cost of traditional carbon negative electrode materials, the carbon negative electrode materials produced by the present invention have low raw material cost, wide sources, simple preparation process, short production cycle, low energy consumption and other advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 This is the SEM spectrum of the negative electrode material prepared by direct carbonization of waste asphalt in Example 1.

[0028] Figure 2 This is the TEM spectrum of the negative electrode material prepared by direct carbonization of waste asphalt in Example 1.

[0029] Figure 3 This is the SEM spectrum of the carbonized negative electrode material of waste asphalt and loofah prepared in Example 2.

[0030] Figure 4 This is the TEM spectrum of the carbonized negative electrode material of waste asphalt and loofah prepared in Example 2.

[0031] Figure 5 This is the XRD spectrum of the negative electrode material prepared in Example 2 by carbonizing waste asphalt and loofah.

[0032] Figure 6 The waste asphalt prepared in Example 2 and the carbonized negative electrode material of the sponge gourd were assembled into a lithium ion battery at 0.2A g -1 Cycling performance diagram at different current densities.

[0033] Figure 7The waste asphalt prepared in Example 2 and the carbonized negative electrode material of the sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0034] Figure 8 The waste asphalt prepared in Example 2 and the carbonized negative electrode material of sponge gourd were assembled into a potassium ion battery at 0.1A g -1 Cycling performance diagram at different current densities.

[0035] Fig. 9 The waste asphalt prepared in Example 1 and the carbonized negative electrode material of the sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0036] Fig.10 The waste asphalt prepared in Example 3 and the carbonized negative electrode material of sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0037] Fig.11 The waste asphalt prepared in Example 4 and the carbonized negative electrode material of the sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0038] Fig.12 The waste asphalt prepared in Example 5 and the carbonized negative electrode material of sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0039] Fig.13 The waste asphalt prepared in Example 6 and the carbonized negative electrode material of the sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0040] Fig.14 The waste asphalt prepared in Example 7 and the carbonized negative electrode material of sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0041] Fig.15 The waste asphalt prepared in Example 8 and the carbonized negative electrode material of the sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0042] Fig.16 The waste asphalt prepared in Example 14 and the carbonized negative electrode material of the sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0043] Fig.17 The waste asphalt prepared in Example 15 and the carbonized negative electrode material of the sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0044] Fig.18 The waste asphalt prepared in Example 16 and the carbonized negative electrode material of the sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0045] Fig.19 The waste asphalt prepared in Example 17 and the carbonized negative electrode material of the sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0046] Fig. 20 The waste asphalt prepared in Example 18 and the carbonized negative electrode material of the sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0047] Fig.21 The waste asphalt prepared in Example 19 and the carbonized negative electrode material of the sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0048] Fig. 22 The waste asphalt prepared in Example 21 and the carbonized negative electrode material of the sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0049] Fig.23 The waste asphalt prepared in Example 1 and the carbonized negative electrode material of the sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0050] Fig.24 The waste asphalt prepared in Example 2 and the carbonized negative electrode material of the sponge gourd were assembled into a sodium ion battery at 0.15A g -1 Cycling performance diagram at different current densities.

[0051] Fig.25 This is the SEM spectrum of the carbonized negative electrode material of loofah prepared in Example 2. DETAILED DESCRIPTION

[0052] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] Example 1

[0054] A method for preparing an internally supported waste asphalt loofah cross-linked derived carbon as a battery negative electrode material, comprising the following steps:

[0055] S1: Wash the waste asphalt mixture with clean water and dry it.

[0056] S2: dissolving the waste asphalt mixture in carbon tetrachloride to separate the oil from the stone, and keeping the separated waste asphalt solution for later use.

[0057] S3: Use hydrochloric acid solution to stir and clean the sponge gourd at 25°C for 3 h, and then vacuum dry it at 50°C for 10 h.

[0058] S4: Grind the dried loofah into powder and add it to the separated waste asphalt solution. Stir it with magnetic force at 80℃ and keep it warm for 6 h.

[0059] S5: Raise the magnetic stirring temperature to 150° C. until the solvent (carbon tetrachloride) is completely volatilized to obtain a composite precursor of waste asphalt and loofah.

[0060] S6: The composite precursor of waste asphalt and loofah was carbonized in a tubular furnace at a temperature of 800°C (heating rate 1°C / min, in a nitrogen atmosphere) for 4 h. After cooling to room temperature, the carbonized negative electrode material of waste asphalt and loofah was obtained.

[0061] Lower carbonization temperature can retain more defects of waste asphalt loofah composite carbon materials, increase the storage sites of alkali metal ions and thus increase the capacity, performance such as Fig. 9 shown.

[0062] Example 2

[0063] A method for preparing an internally supported waste asphalt loofah cross-linked derived carbon as a battery negative electrode material, comprising the following steps:

[0064] S1: Wash the waste asphalt mixture with clean water and dry it.

[0065] S2: dissolving the waste asphalt mixture in carbon tetrachloride to separate the oil from the stone, and keeping the separated waste asphalt solution for later use.

[0066] S3: Use nitric acid solution to stir and clean the sponge gourd at 30°C for 2 h, and then vacuum dry it at 100°C for 6 h.

[0067] S4: Grind the dried loofah into powder and add it to the separated waste asphalt solution. Stir it with magnetic force at 80℃ and keep it warm for 6 h.

[0068] S5: Raise the magnetic stirring temperature to 150° C. until the solvent (carbon tetrachloride) is completely volatilized to obtain a composite precursor of waste asphalt and loofah.

[0069] S6: The composite precursor of waste asphalt and loofah was carbonized in a tubular furnace at a temperature of 1400°C (heating rate of 2°C / min, in an argon atmosphere) for 2 h. After cooling to room temperature, the carbonized negative electrode material of waste asphalt and loofah was obtained.

[0070] Higher carbonization temperature can promote the deep filling and compounding of the porous carbon material formed by the sponge gourd with the asphalt-derived carbon material, forming a pore structure material with a smaller specific surface area, which improves the storage capacity of alkali metal ions and the first coulomb efficiency; performance such as Figure 5-8 shown.

[0071] Compared with conventional asphalt, conventional asphalt will undergo an uncontrollable fusion carbonization process at high temperature (400-600°C) to form a regular thick graphite structure. This thick graphite structure not only has a narrow interlayer spacing, but also blocks the transmission of sodium, affecting the intercalation and embedding performance of sodium. The embodiment of the present invention uses the natural porous material loofah as an induced product to induce waste asphalt-derived carbon from a highly ordered thick graphite structure to form a three-dimensional internal support carbon material ( Figure 3-4 ). As a typical biomass material, loofah sponge has a natural porous three-dimensional structure, and then the waste asphalt and loofah sponge are fully compounded to form a flexible structure with natural internal support. During the pyrolysis process, the excess oxygen components in the loofah sponge will consume the hydrogen elements in the waste asphalt. At the same time, the loofah sponge provides attachment and condensation sites, inducing the turbine-like multi-directional accumulation of graphene, forming sp2 and sp3 hybrid structures while expanding the distance between carbon layers, thereby forming a disordered carbon microcrystalline material with rich closed pore structures and tunnels.

[0072] Example 3

[0073] A method for preparing an internally supported waste asphalt loofah cross-linked derived carbon as a battery negative electrode material, comprising the following steps:

[0074] S1: Wash the waste asphalt mixture with clean water and dry it.

[0075] S2: dissolving the waste asphalt mixture in carbon tetrachloride to separate the oil from the stone, and keeping the separated waste asphalt solution for later use.

[0076] S3: Wash the sponge gourd with sulfuric acid solution at 30°C for 2 h, and then vacuum dry it at 100°C for 6 h.

[0077] S4: Grind the dried loofah into powder and add it to the separated waste asphalt solution. Stir it with magnetic force at 25℃ and keep it warm for 12 h.

[0078] S5: Raise the magnetic stirring temperature to 120° C. until the solvent (carbon tetrachloride) is completely volatilized to obtain a composite precursor of waste asphalt and loofah.

[0079] S6: The composite precursor of waste asphalt and sponge gourd was carbonized in a tube furnace at 1200°C (heating rate 10°C / min, argon atmosphere) for 2 h. After cooling to room temperature, the carbonized negative electrode material of waste asphalt and sponge gourd was obtained. Fig.10 As shown, the deep oxygen structure is detached, the oxygen content decreases, and closed pores are initially formed at 1200℃, which can provide more storage sites.

[0080] Example 4

[0081] A method for preparing an internally supported waste asphalt and loofah sponge cross-linked derived carbon as a battery negative electrode material: except for S6, a composite precursor of waste asphalt and loofah sponge is high-temperature carbonized in a tubular furnace at a temperature of 1000°C for 2 h, and the carbonized negative electrode material of waste asphalt and loofah sponge is obtained after cooling to room temperature.

[0082] The rest is the same as in Example 2. Fig.11 As shown, compared with the product of 800°C (Example 1), this example has fewer defects, a weaker ability to adsorb alkali metal ions, and a relatively lower capacity.

[0083] Example 5

[0084] A method for preparing an internally supported waste asphalt and loofah sponge cross-linked derived carbon as a battery negative electrode material: except for S6, a composite precursor of waste asphalt and loofah sponge is high-temperature carbonized in a tubular furnace at a temperature of 1300°C for 2 h, and the carbonized negative electrode material of waste asphalt and loofah sponge is obtained after cooling to room temperature.

[0085] The rest is the same as in Example 2. Fig.12 As shown, the graphene stacking is further ordered to form a multi-layer cross-linked structure of ordered carbon layers and disordered structures, and the number of closed pore structures formed increases, which can provide more capacity.

[0086] Example 6

[0087] A method for preparing an internally supported waste asphalt and loofah sponge cross-linked derived carbon as a battery negative electrode material: except for S6, a composite precursor of waste asphalt and loofah sponge is high-temperature carbonized in a tubular furnace at a temperature of 1500°C for 2 hours, and after cooling to room temperature, a carbonized negative electrode material of waste asphalt and loofah sponge is obtained.

[0088] The rest is the same as in Example 2. Fig.13 As shown, compared with the 1400°C material (Example 2), the pores expand, partially stretched long-range ordered regions begin to appear, the distance between carbon layers decreases, and the storage capacity begins to decrease.

[0089] Example 7

[0090] A method for preparing an internally supported waste asphalt and loofah sponge cross-linked derived carbon as a battery negative electrode material: except for S6, a composite precursor of waste asphalt and loofah sponge is high-temperature carbonized in a tubular furnace at a temperature of 1600°C for 2 h, and the carbonized negative electrode material of waste asphalt and loofah sponge is obtained after cooling to room temperature.

[0091] The rest is the same as in Example 2. Fig.14 As shown, a higher carbonization temperature can improve the order of waste asphalt loofah composite carbon materials and reduce the carbon layer spacing. At the same time, some small closed cells expand and combine to form a larger open-pore structure.

[0092] The interlayer spacing in Example 7 is smaller than that in Example 6, which makes the embedding of sodium ions more difficult. At the same time, the closed-cell expansion forms an open-cell structure, which leads to a relative decrease in the first effect.

[0093] Example 8

[0094] A method for preparing an internally supported waste asphalt and loofah sponge cross-linked derived carbon as a battery negative electrode material: except for S6, the composite precursor of waste asphalt and loofah sponge is high-temperature carbonized in a tubular furnace at a temperature of 600°C for 2 h, and the carbonized negative electrode material of waste asphalt and loofah sponge is obtained after cooling to room temperature.

[0095] The rest is the same as in Example 2. Fig.15 As shown, there are many defects but they are not easy to separate after combining with alkali metal ions, forming a large amount of irreversible capacity and a high first discharge capacity.

[0096] Example 9

[0097] A method for preparing an internally supported waste asphalt loofah sponge cross-linked derived carbon as a battery negative electrode material: except that in S3, a water regia solution (a mixture of concentrated hydrochloric acid and concentrated nitric acid in a volume ratio of 3:1) is used to stir and wash the loofah sponge at 25°C for 2 hours; the rest is the same as Example 2.

[0098] Aqua regia has a stronger cleaning effect than ordinary sulfuric acid, and can avoid the strong dehydration properties of concentrated sulfuric acid.

[0099] Example 10

[0100] A method for preparing an internally supported waste asphalt loofah sponge cross-linked derived carbon as a battery negative electrode material: except that in S3, the loofah sponge is washed with nitric acid solution (mass fraction 65%) and sodium hydroxide solution (mass fraction 5%) at 25°C for 2 hours in sequence; the rest is the same as Example 2.

[0101] Nitric acid has stronger oxidizing properties, and further oxidizes the loofah during the cleaning process, so that after the asphalt is compounded with it, more small pore structures are formed during the carbonization process, which promotes the embedding and removal of alkali metals.

[0102] Embodiment 11

[0103] A method for preparing an internally supported waste asphalt and loofah cross-linked derived carbon as a negative electrode material for a battery: the waste asphalt and loofah carbonized negative electrode material prepared in Example 2 is stirred and washed with sulfuric acid solution (mass fraction 50%) and sodium hydroxide solution (mass fraction 10%) at 40°C for 3 hours, and then washed and filtered with ultrapure water until neutral. Acid washing helps to remove residual metal ions such as potassium and magnesium in the carbon material, and alkali washing can remove acidic oxides such as sulfate groups, and the residual acid is further removed after acid washing. The product obtained after acid washing and alkali washing has higher purity and less impurities.

[0104] Example 12

[0105] A method for preparing an internally supported waste asphalt and loofah cross-linked derived carbon as a negative electrode material for a battery: except that in S6, the carbonized negative electrode material of waste asphalt and loofah prepared in Example 3 is ultrasonically washed with an ethanol solution at 50° C. for 2 h; after cleaning, it is washed with ultrapure water and filtered to neutrality, and further dried in an air oven at 120° C. for 10 hours. The rest is the same as Example 3.

[0106] Wash away some of the organic substances adhering to the carbon material. During annealing and cooling, there are residual organic substances in the tube furnace, which will adhere to the carbon material. Ethanol can be used to wash away some of the organic substances.

[0107] Embodiment 13

[0108] A method for preparing an internally supported waste asphalt and loofah cross-linked derived carbon as a negative electrode material for a battery: except that in S6, the carbonized negative electrode material of waste asphalt and loofah prepared in Example 3 is ultrasonically washed with an ethanol solution at 50°C for 2 h; after cleaning, it is washed with ultrapure water and filtered to neutrality, and further dried in a vacuum oven (120°C, 10 hours). The rest is the same as Example 3.

[0109] Compared with drying in ordinary air, the vacuum oven does not introduce oxygen during the drying process. At the same time, the drying degree is more thorough, the residual moisture is less, and the performance of the carbon material is better.

[0110] Embodiment 14

[0111] A method for preparing an internally supported waste asphalt and loofah sponge cross-linked derived carbon as a negative electrode material for a battery: except that in S6, the composite precursor of waste asphalt and loofah sponge prepared in S5 of Example 3 is first pre-carbonized at 400° C.; the pre-carbonized sample is washed with sulfuric acid (mass fraction 50%), then washed and filtered with ultrapure water until neutral, and then carbonized at 1400° C.;

[0112] The rest is the same as Example 3.

[0113] Pre-carbonization low-temperature treatment will leave more heteroatoms. At the same time, compared with carbonization at a temperature above 1000 degrees and then pickling, the sulfur atoms introduced in this stage can be removed at high temperature. Performance such as Fig.16 shown.

[0114] Embodiment 15

[0115] A method for preparing an internally supported waste asphalt and loofah sponge cross-linked derived carbon as a negative electrode material for a battery: except that in S6, the composite precursor of waste asphalt and loofah sponge prepared in S5 of Example 13 is first pre-carbonized at 200° C.; the pre-carbonized sample is washed with sulfuric acid (mass fraction 50%), then washed and filtered with ultrapure water until neutral, and then carbonized at 1400° C.;

[0116] The rest are the same as in Example 13, and the performance is as follows Fig.17 shown.

[0117] Example 16

[0118] A method for preparing an internally supported waste asphalt and loofah sponge cross-linked derived carbon as a negative electrode material for a battery: except that in S6, the composite precursor of waste asphalt and loofah sponge prepared in S5 of Example 13 is first pre-carbonized at 300° C.; the pre-carbonized sample is washed with sulfuric acid (mass fraction 50%), then washed and filtered with ultrapure water until neutral, and then carbonized at 1400° C.;

[0119] The rest are the same as in Example 13, and the performance is as follows Fig.18 shown.

[0120] Embodiment 17

[0121] A method for preparing an internally supported waste asphalt loofah sponge cross-linked derived carbon as a battery negative electrode material: except that the solvent in S2 is benzene, the rest is the same as Example 2.

[0122] Performance as Fig.19 As shown, benzene is a polar solvent, which has a stronger binding ability for polar components and aromatic tissues. It can guide the aromatic groups to deeply recombine with the loofah sponge. The deeply composited precursor is helpful for the hybrid stacking of carbonized graphene, further improving the performance of carbon materials.

[0123] Embodiment 18

[0124] A method for preparing an internally supported waste asphalt loofah sponge cross-linked derived carbon as a battery negative electrode material: except that the solvent in S2 is a mixed solution of benzene and tetrahydrofuran in a ratio of 3:1 (mass ratio), the rest is the same as Example 2.

[0125] Performance as Fig. 20 As shown. Using a relatively excessive amount of benzene, supplemented with a non-polar solution, the entire component of waste asphalt is deeply extracted and then compounded with loofah. Deep extraction makes more complete use of asphalt, more asphalt is cross-linked with loofah, the degree of hybridization is deeper, and the resulting carbon material has a higher capacity retention rate.

[0126] Embodiment 19

[0127] A method for preparing an internally supported waste asphalt loofah sponge cross-linked derived carbon as a battery negative electrode material: except that the solvent in S2 is a mixed solution of benzene and tetrahydrofuran in a ratio of 1:1 (mass ratio), the rest is the same as Example 2.

[0128] Performance as Fig.21 As shown. A more uniform polar non-polar solution is formed, so that the various components of waste asphalt at the composite interface of the loofah are in more uniform contact. Each component adheres to the loofah, the precursor microstructure diversity is stronger, the carbon material structure formed is more multidirectional, the degree of hybridization is deeper, and the resulting carbon material has a higher capacity.

[0129] In the embodiment of the present invention, the solvent for separating the oilstone from the waste asphalt mixture in S2 includes: a polar solvent, a non-polar solvent or a mixed solvent obtained by mixing a polar solvent with a non-polar solvent, specifically any one or more of carbon tetrachloride, dichloromethane, chloroform, 1,1,1-trichloroethane, trichloroethylene, 1-bromopropane, chlorobenzene, nitrobenzene, tetrahydrofuran, ethyl acetate, xylene, toluene, benzene, tetralin, methylcyclopentane, cyclohexane, n-pentane, n-hexane or decahydronaphthalene.

[0130] Embodiment 20

[0131] A method for preparing an internally supported waste asphalt loofah sponge cross-linked derived carbon as a negative electrode material for a battery: except that the loofah sponge is washed with nitric acid solution and sodium hydroxide solution at 25°C for 2 h in sequence in S3; the rest is the same as Example 19. The uniform waste asphalt is compounded with the loofah sponge washed with oxidative acid to improve the electrochemical stability of the product. Compared with Example 10, Example 20 has richer defects and macroporous structures of the loofah sponge washed with acid and alkali, more uniform adhesion with each component, stronger precursor microstructure diversity, deeper hybridization, and higher capacity of the obtained carbon material.

[0132] The acidic solution in S3 of the embodiment of the present invention is any one or more of sulfuric acid, hydrochloric acid, nitric acid, acetic acid, carbonic acid or aqua regia mixed in any proportion; the alkaline solution in S3 is any one or more of ammonia water, sodium hydroxide, calcium hydroxide or potassium hydroxide mixed in any proportion.

[0133] Embodiment 21

[0134] A method for preparing an internally supported waste asphalt loofah cross-linked derived carbon as a battery negative electrode material, comprising the following steps:

[0135] S1: Wash the waste asphalt mixture with clean water and dry it.

[0136] S2: dissolving the waste asphalt mixture in dichloromethane to separate the oil from the stone, and keeping the separated waste asphalt solution for later use.

[0137] S3: Wash the sponge gourd with sulfuric acid solution at 100°C for 1 h, and then vacuum dry it at 100°C for 8 h.

[0138] S4: Grind the dried loofah into powder and add it to the separated waste asphalt solution. Stir it with magnetic force at 100℃ and keep it warm for 2 h.

[0139] S5: Raise the magnetic stirring temperature to 100° C. until the solvent (dichloromethane) is completely volatilized to obtain a composite precursor of waste asphalt and loofah.

[0140] S6: The composite precursor of waste asphalt and sponge gourd was carbonized in a tube furnace at 700°C (heating rate 2°C / min, in argon atmosphere) for 2 h. After cooling to room temperature, the carbonized negative electrode material of waste asphalt and sponge gourd was obtained. Fig. 22 shown.

[0141] Comparative Example 1

[0142] Preparation of negative electrode materials using waste asphalt as raw material:

[0143] S1: Wash the waste asphalt mixture with clean water and dry it.

[0144] S2: dissolving the waste asphalt mixture in carbon tetrachloride to separate the oil from the stone, and keeping the separated waste asphalt solution for later use.

[0145] S3: The separated waste asphalt solution is subjected to magnetic stirring, and the magnetic stirring temperature is increased to 150° C. until the solvent is completely volatilized to obtain a waste asphalt precursor.

[0146] S4: The waste asphalt material was uniformly carbonized in a tube furnace at 1400°C (heating rate 2°C / min, in argon atmosphere) for 2 h. After cooling to room temperature, the directly carbonized waste negative electrode material was obtained, such as Figure 1-2 shown.

[0147] Directly carbonizing waste asphalt at high temperature will result in a carbon material with a narrow carbon layer spacing, which is not conducive to the storage of alkali metal ions; performance such as Fig.23 shown.

[0148] Comparative Example 2

[0149] Preparation of negative electrode materials using waste asphalt and loofah as raw materials:

[0150] S1: Wash the waste asphalt mixture with clean water and dry it.

[0151] S2: dissolving the waste asphalt mixture in carbon tetrachloride to separate the oil from the stone, and keeping the separated waste asphalt solution for later use.

[0152] S3: The separated waste asphalt solution is subjected to magnetic stirring, and the magnetic stirring temperature is increased to 150° C. until the solvent is completely volatilized to obtain a waste asphalt precursor.

[0153] S4: The waste asphalt material and the loofah material were carbonized separately in a tubular furnace at a temperature of 1400°C (heating rate of 2°C / min, in an argon atmosphere). The high-temperature carbonization time was 2 h. After cooling to room temperature, the directly carbonized waste negative electrode material and loofah material were obtained.

[0154] S5: Grinding composite loofah carbon material and waste asphalt composite carbon material (such as Fig.25 Assemble the battery.

[0155] The above-mentioned method of compounding waste asphalt and loofah material cannot play a synergistic regulatory role, and the compounding is insufficient, which affects the performance of the composite carbon material in alkali metal ion batteries. Fig.24 shown.

[0156] In the embodiment of the present invention, "internal support" specifically refers to: 1. Waste asphalt is attached to the loofah sponge, and the loofah sponge serves as an internal skeleton, supporting the waste asphalt material on a macro scale; 2. After carbonization, the sp3 hybridized carbon microcrystals derived from the loofah serve as a skeleton at the microscopic level, and the asphalt-derived carbon is further stacked. This internal support structure enables the composite derived carbon to have more sites and better performance.

[0157] In the embodiment of the present invention, the sponge gourd is organic and has a porous structure. Based on its own structural characteristics, different solvents are regulated to extract waste asphalt and the sponge gourd to form a deep composite. At the same time, during the high-temperature carbonization process, the carbon microcrystals derived from the sponge gourd and the carbon microcrystals derived from the waste asphalt are mutually regulated to further evolve into an internally supported porous structure. The sponge gourd also participates in forming a part of the carbon skeleton of the final product to obtain an internally supported pore structure. Figure 1 and Figure 3 By comparison, it can be seen that after regulation, the carbon microcrystals are cross-linked with each other, forming a multi-layer internal support structure with disordered carbon as the skeleton.

[0158] Waste asphalt is a waste in the transportation field. The exploration and research of waste asphalt is mostly for transportation reuse. At the same time, waste asphalt is combined with stone. In order to achieve the reuse effect, the waste asphalt needs to be stripped first. The mechanical method has low purity and small separation rate. The chemical solvent method needs to consume solvent to obtain the asphalt itself, and then use it for other purposes. While using solvent to strip asphalt, the embodiment of the present invention reduces the step of obtaining recycled asphalt, directly uses solvated asphalt to combine with loofah to further form negative electrode materials, achieving the effect of killing two birds with one stone. Waste asphalt has been subjected to various aging factors such as high temperature and ultraviolet rays during road service. Its cross-linked structure is very different from conventional asphalt, and its aromatic content decreases and asphaltene content increases. Waste asphalt cannot be reused by conventional asphalt treatment methods. Therefore, multiple experiments are required to determine the acid, alkali and salt treatment methods, thermal control methods, the degree of combination of solvated waste asphalt and loofah, the flow and dispersion, adhesion and shedding of waste asphalt during heat treatment, and comprehensive considerations can form a complete method system, which has great technical difficulty.

[0159] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A method for preparing an internally supported waste asphalt loofah cross-linked derived carbon as a negative electrode material for a battery, It is characterized in that The following steps are involved: S1: Wash the waste asphalt mixture with clean water and dry it; S2: adding the waste asphalt mixture into a solvent to separate the oil and stone, and the separated waste asphalt solution is used for later use; S3: washing the sponge gourd with an acidic solution or an alkaline solution, or with an acidic solution and an alkaline solution in sequence, and vacuum drying the sponge gourd after washing; S4: Grind the dried loofah into powder, add it to the separated waste asphalt solution, stir it with magnetic force at 25℃~100℃, and keep it warm for 2h~12h; S5: raising the magnetic stirring temperature to 100°C-150°C until the solvent is completely volatilized to obtain a composite precursor of waste asphalt and loofah sponge; S6: Carbonizing the composite precursor of waste asphalt and loofah in a tubular furnace at a temperature of 600°C to 1600°C for 1 h to 4 h, and obtaining the carbonized negative electrode material of waste asphalt and loofah after cooling to room temperature; In S3, the acidic solution is any one or more of sulfuric acid, nitric acid or aqua regia mixed in any proportion; In S3, the alkaline solution is any one or more of ammonia water, sodium hydroxide, calcium hydroxide or potassium hydroxide mixed in any proportion.

2. A method for preparing an internally supported waste asphalt loofah cross-linked derived carbon as a negative electrode material for a battery according to claim 1, It is characterized in that In S2, the solvent is a polar solvent, a non-polar solvent, or a mixed solvent of a polar solvent and a non-polar solvent.

3. A method for preparing an internally supported waste asphalt loofah cross-linked derived carbon as a negative electrode material for a battery according to claim 1, It is characterized in that In S2, the solvent is any one or more of carbon tetrachloride, dichloromethane, chloroform, 1,1,1-trichloroethane, trichloroethylene, 1-bromopropane, chlorobenzene, nitrobenzene, tetrahydrofuran, ethyl acetate, xylene, toluene, benzene, tetralin, methylcyclopentane, cyclohexane, n-pentane, n-hexane or decahydronaphthalene.

4. A method for preparing an internally supported waste asphalt loofah cross-linked derived carbon as a negative electrode material for a battery according to claim 1, It is characterized in that In the S2, the solvent is a mixture of benzene and tetrahydrofuran in a ratio of 1 to 3:

1.

5. A method for preparing an internally supported waste asphalt loofah cross-linked derived carbon as a negative electrode material for a battery according to claim 1, It is characterized in that In S6, the heating rate of high temperature carbonization is 1°C / min to 10°C / min.

6. A method for preparing an internally supported waste asphalt loofah cross-linked derived carbon as a negative electrode material for a battery according to claim 1, It is characterized in that In S6, the high temperature pyrolysis atmosphere is: any one of nitrogen or argon or a mixture of the two in any ratio.

7. A method for preparing an internally supported waste asphalt loofah cross-linked derived carbon as a negative electrode material for a battery according to claim 1, It is characterized in that Also includes: The waste asphalt prepared by S6 and the carbonized negative electrode material of loofah are stirred and cleaned with sulfuric acid solution and sodium hydroxide solution at 40-50°C for 2-3 hours, or ultrasonically cleaned with ethanol solution for 2-3 hours. After cleaning, they are washed with ultrapure water and filtered until neutral; and then dried in a vacuum oven.

8. A method for preparing an internally supported waste asphalt loofah cross-linked derived carbon as a negative electrode material for a battery according to claim 1, It is characterized in that Prior to S6, the sample was pre-carbonized at 200-400°C, and the pre-carbonized sample was cleaned with sulfuric acid, and then washed with ultrapure water and filtered until neutral.

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