Graphite and graphene dispersing agent and application thereof

Abstract

The invention relates to a graphite and graphene dispersing agent and application thereof.The composition is formed by combining alkyl sulfosuccinate and polyalkylene glycol through a synergistic effect, graphite and graphene can be easily and rapidly dispersed in a medium by means of a proper adding amount, the dispersion uniformity and stability of the graphite and the graphene are improved, sedimentation of the graphite and the graphene is delayed, and the graphite and the graphene can be effectively dispersed. And the re-stacking is inhibited. In addition, the graphite and the graphene can be applied to other media except non-water-based or organic solvents. The composition provided by the invention does not contain flammable volatile chemical substances, does not contain any fluorine, silicon or phosphorus-based compounds, and does not contain any aryl substances. According to the invention, not only can environmental pollution be reduced, but also the operation safety of related personnel can be improved.

Description

Technical Field

[0001] The present invention relates to a graphite and graphene dispersant and its application. Background Art

[0002] Graphite is an allotrope of carbon, with high chemical stability, resistance to strong acids and bases, fire resistance, good electrical and thermal conductivity. Since graphite is a non-polar solid substance, it is difficult to disperse in water, which limits its applications. In order to make graphite disperse evenly in water, an appropriate and efficient surfactant composition is urgently needed to improve the wettability, dispersibility and permeability of water to graphite, so as to expand the scope of graphite (including natural flake graphite, spheroidal graphite, expanded graphite, etc.) in industrial aqueous applications.

[0003] Currently, common production methods of graphene are mechanical exfoliation method, liquid phase exfoliation method (Liquid phase exfoliation, including oxidation-reduction method and solvent exfoliation method), chemical vapor deposition method (CVD, Chemical Vapor Deposition). Although the mechanical exfoliation method can prepare high-quality graphene, it has the disadvantages of low yield and high cost, and there are also problems of difficult dispersion and easy agglomeration, which do not meet the requirements of industrialization and large-scale production. Although the chemical vapor deposition method can meet the requirements of large-scale preparation of high-quality graphene, it has high cost and complex process. Although the liquid-phase ultrasonic exfoliation method has low preparation cost and is easy to implement, and may become the best method for preparing graphene, the disadvantage of the oxidation-reduction method is that a large amount of preparation is likely to cause waste liquid pollution, and the prepared graphene has certain defects, resulting in the loss of some electrical properties of graphene, which limits the application of graphene. Although the current general solvent exfoliation method can prepare high-quality graphene, the disadvantage is that it must use solvents that are difficult to remove and toxic, such as N-methylpyrrolidone (NMP) or dimethylformamide (DMF), etc., to form a graphite dispersion liquid, and then perform ultrasonic exfoliation. If water added with an efficient dispersant can be used to form a graphite-dispersed aqueous solution, and then ultrasonic exfoliation is carried out, not only can the use of solvents that are difficult to remove and toxic be avoided, but also the concentration of graphite in the dispersed aqueous solution may be increased, and the yield of graphene may be improved.

[0004] Since graphene is composed of sp 2The planar conjugated structure composed of hybridized carbon atoms has very strong π-π interaction and van der Waals force between its sheets, and has a large specific surface area, resulting in extremely poor dispersibility. Graphene has a wide range of applications, such as: conductive materials, antistatic materials, thermal conductive / heat dissipation materials, flame retardant materials, anticorrosive coatings, waterproof coatings, reinforced cement, asphalt and antibacterial materials. Graphene sheets are not easy to disperse evenly in the application medium, and are easy to aggregate, stack and agglomerate. Even after a short dispersion, they may reunite immediately. Reunion will prevent graphene from showing its unique and excellent physical properties, such as conductivity, heat dissipation, flame retardancy, anticorrosion, waterproofing, reinforcement, adsorption, antibacterial, etc.

[0005] The most common problem in graphene applications is how to evenly disperse graphene sheets and prevent them from agglomerating with each other. This has always been the most pressing technical bottleneck to be solved in the industry. In addition, the application preparation process requires that graphene be dispersed in water or non-toxic organic solvents for operability and processability. Although traditional commercial surfactants, such as sodium dodecylbenzene sulfonate (SDBS), hexadecyltrimethylammonium bromide (CTAB), phenyl-polyethylene glycol (Triton-X-100), polysorbate 80 (Tween 80) and polymer stabilizers (for example, polyvinyl pyrrolidone (PVP), sodium polystyrene sulfonate (PSS), polydimethyldiallylammonium chloride (PDDA), etc.) can play a certain role in dispersing and stabilizing graphene, there are often problems such as large amount of dispersant and low graphene concentration. Excessive amount of dispersant and too low graphene concentration are both unfavorable factors for constructing composite materials. The biggest challenge facing graphene application development technology at present is how to find appropriate and efficient graphene dispersants.

[0006] TW201620607A discloses a graphene dispersant, which includes an aniline oligomer or an aniline oligomer derivative, and the aniline oligomer or the aniline oligomer derivative is an electroactive polymer. CN105645388A discloses a graphene dispersant, which includes an electroactive aniline oligomer and / or its derivative. TW202311355A discloses the use of a polyalkylene oxide having at least one aromatic group as a dispersant for graphene materials. However, these are all benzene-containing substances, which have poor biodegradability. TW201711959A discloses a graphene dispersion, which is a dispersion formed by graphene dispersed in a solvent containing more than 50wt% of N-methylpyrrolidone (NMP, flash point 86.1°C), using a large amount of flammable organic solvents with considerable toxicity.

[0007] Graphene Oxide (GO) flakes are the product of chemically oxidizing and exfoliating graphite powder. Graphene Oxide has long been regarded as a hydrophilic substance because of its excellent dispersibility in water. However, since the mechanical properties of Graphene Oxide are determined by details such as the degree of oxidation and thickness, there are still some deficiencies in its applications. Because structural defects will affect its physical properties, the applicability of Graphene Oxide is limited.

[0008] Current research on graphene has involved applications in drug delivery carriers, tumor treatment, antibacterial and sterilization, and artificial implant devices. The interaction between graphene and pathogens is largely affected by the physicochemical properties of graphene, such as surface-related properties, shape, size, dispersibility, functionalization, and electronic structure. Graphene Oxide has oxygen-containing functional groups, can be dispersed in water, and is easily dispersed in many solvents, so it is widely used in biomedicine. However, the oxygen functional groups contained in Graphene Oxide belong to Reactive Oxygen Species (ROS), which will cause oxidative stress and may constitute the main mechanism inducing pathological changes. The use of pristine graphene, which is easily dispersed, can reduce the induction of such pathological changes.

[0009] In nuclear power plants, neutralizing radioactive waste is one of the major problems faced by the economy and science in the 21st century. Graphene can adsorb radioactive substances in nuclear power plant wastewater and form lumps, remove these lumps from the liquid, and then recycle or burn them, thereby improving the storage method of radioactive waste, reducing its quantity, and avoiding leakage risks. According to the preliminary calculations of those skilled in the art, each kilogram of graphene can purify approximately 25 grams of radioactive substances. Current related research uses Graphene Oxide, which is more easily dispersed in water. However, due to the structural defects caused by the oxidation process implicit in Graphene Oxide, it has a negative impact on its adsorption, and its manufacturing will cause environmental chemical pollution. Therefore, there is an urgent need for a dispersant that can easily disperse pristine graphene in water to more effectively treat the radioactive waste liquid in nuclear power plants.

[0010] So far, due to their physical properties, graphite and graphene are not easily formed into a dispersed aqueous solution. In the case of graphene, generally only a water dispersion of Graphene Oxide can be produced, resulting in a great limitation in the application scope of graphite and graphene. There is an urgent need for a graphite and graphene dispersant that can manufacture solid or liquid graphite material materials (powdered, flaky, spherical, expanded, etc.) and graphene material materials that are easily dispersed in water, as well as their related nanocarbon materials (such as nanotubes, nanosheets, quantum dots, sponges, etc.) to expand the possible application scope of graphite and graphene.

[0011] In view of the above, the main object of the present invention is to provide a graphite and graphene dispersant and a method for dispersing graphite and graphene. Through this dispersant, graphite, graphene or their combination can be uniformly dispersed, so as to realize applications in various different fields. In particular, a flammable organic solvent without aryl substances and without toxicity is provided, which can quickly and uniformly disperse graphite, graphene or their combination in water to form a dispersion solution with a high concentration of graphite, graphene or their combination. This is an urgent problem to be overcome in the current industrial applications of graphite, graphene or their combination. Summary of the Invention

[0012] In view of this, the present invention provides a graphite and graphene dispersant and a method for dispersing graphite and graphene, which do not contain toxic substances, volatile chemical substances or organic solvents, do not contain any fluorine-, silicon- or phosphorus-based compounds or any aromatic compounds, are environmentally friendly and safe for humans and animals, and have excellent dispersibility for graphite, graphene or their combination, enabling graphite, graphene or their combination to be uniformly dispersed in water, improving the wettability, dispersibility and permeability of water to them, so as to expand the scope of industrial aqueous applications.

[0013] To achieve the above object, according to one aspect of the present invention, a graphite and graphene dispersant is provided, which includes alkyl sulfosuccinate and polyalkylene glycol, wherein the weight ratio of alkyl sulfosuccinate to polyalkylene glycol is between 1:99 and 99:1, for example, between 1:9 and 9:1, between 2:8 and 8:2, or between 3:7 and 7:3, but the present invention is not limited thereto.

[0014] In the graphite and graphene dispersant of the present invention, the alkyl sulfosuccinate can be monoalkyl sulfosuccinate, dialkyl sulfosuccinate, polyalkyl sulfosuccinate or a combination thereof. Among them, the monoalkyl sulfosuccinate can have a 1-18 carbon chain alkyl group, preferably a 4-18 carbon chain alkyl group, more preferably a 4-12 carbon chain alkyl group, and further more preferably a 6-8 carbon chain alkyl group; the dialkyl sulfosuccinate can have two identical or different 1-18 carbon chain alkyl groups, preferably a 4-18 carbon chain alkyl group, more preferably a 4-12 carbon chain alkyl group, and further more preferably a 6-8 carbon chain alkyl group; and the polyalkyl sulfosuccinate can have multiple identical or different 1-18 carbon chain alkyl groups, preferably a 4-18 carbon chain alkyl group, more preferably a 4-12 carbon chain alkyl group, and further more preferably a 6-8 carbon chain alkyl group, but the present invention is not limited thereto.

[0015] In the graphite and graphene dispersant of the present invention, the alkyl sulfosuccinate can be an alkyl sulfosuccinate having the following chemical formula:

[0016] CH2—COOR1

[0017] |

[0018] CH—COOR2

[0019] |

[0020] SO3Na

[0021] Among them, R1 and R2 can be alkyl groups respectively, but the present invention is not limited thereto. In addition, R1 and R2 can be alkyl groups with 1 to 18 carbon chains respectively, preferably alkyl groups with 4 to 18 carbon chains, more preferably alkyl groups with 4 to 12 carbon chains, and further more preferably alkyl groups with 6 to 8 carbon chains, but the present invention is not limited thereto. In addition, R1 and R2 can be the same or different alkyl groups, and are preferably the same alkyl group.

[0022] In the present invention, the so-called "alkyl group" includes straight-chain and branched-chain alkyl groups. For example, it includes straight-chain and branched-chain C 1-18 alkyl group, C 4-18 alkyl group, C 4-12 alkyl group or C 6-8 alkyl group; and specific examples thereof include, but are not limited to: hexyl, heptyl or octyl.

[0023] In the graphite and graphene dispersant of the present invention, polyalkylene glycol can have the following chemical formula:

[0024]

[0025] Among them, the ratio of n and m can be between 1 and 10, and the molecular weight of polyalkylene glycol can be between 500 and 6000, such as between 800 and 6000, between 1000 and 5000, between 2000 and 5000, or between 2500 and 5000, but the present invention is not limited thereto.

[0026] In the graphite and graphene dispersant of the present invention, the addition amount of the graphite and graphene dispersant in the dispersion medium can be between 0.01 wt% and 10 wt% of the weight of the dispersion medium, such as between 0.05 wt% and 10 wt%, between 0.1 wt% and 10 wt%, between 0.1 wt% and 8 wt%, between 0.1 wt% and 5 wt%, or between 0.1 wt% and 3 wt%, but the present invention is not limited thereto.

[0027] In the graphite and graphene dispersant of the present invention, the dispersion medium can be water, organic solvent, resin, latex, plastic, coating, concrete, ceramic, asphalt, oil product, metal material or a combination thereof, but the present invention is not limited thereto.

[0028] In the graphite and graphene dispersant of the present invention, the graphite and graphene dispersant can be used to manufacture solid or liquid graphite-based materials (powdered, flaky, spherical, expanded, etc.), graphene-based materials, and related nanocarbon materials (such as nanotubes, nanosheets, quantum dots, sponges, etc.) that are easily dispersible in water, but the present invention is not limited thereto.

[0029] In the graphite and graphene dispersant of the present invention, the graphite and graphene dispersant may not contain any flammable organic solvents, may not contain any fluorine, silicon, or phosphorus compounds, or may not contain any aromatic compounds, but the present invention is not limited thereto.

[0030] According to another aspect of the present invention, a method for dispersing graphite and graphene is proposed, including the following steps: (a) preparing the above-mentioned graphite and graphene dispersant; and (b) mixing the graphite and graphene dispersant obtained in (a) with a carbon material to disperse the carbon material, where the carbon material is graphite, graphene, or a combination thereof.

[0031] In the method of the present invention, a liquid-phase exfoliation method and a mechanical exfoliation method can be used to disperse graphite, graphene, or a combination thereof, but the present invention is not limited thereto.

[0032] In the method of the present invention, graphite, graphene, or a combination thereof can be applied to electrical conduction, heat dissipation, flame retardancy, anti-corrosion, waterproofing, strengthening, adsorption, antibacterial, or a combination thereof, but the present invention is not limited thereto.

[0033] In the method of the present invention, graphite, graphene, or a combination thereof can be applied to biomedical liquids, but the present invention is not limited thereto.

[0034] In the method of the present invention, graphite, graphene, or a combination thereof can be applied to treating radioactive discharge liquids in nuclear power plants, but the present invention is not limited thereto.

[0035] In the method of the present invention, the above-mentioned graphite and graphene dispersant can be applied by means of mixing, dispersing, spraying, coating, extrusion, ball milling, or a combination thereof, but the present invention is not limited thereto.

[0036] As will be described in detail below, other objects, advantages, and novel features of the present invention will become more apparent. Detailed Description of the Invention

[0037] To make the objects, technical solutions, and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to specific embodiments.

[0038] The following provides different embodiments of the present invention. These embodiments are used to illustrate the technical content of the present invention and are not used to limit the scope of protection of the claims of the present invention. A feature of one embodiment can be applied to other embodiments through appropriate modification, substitution, combination, and separation.

[0039] In this text, unless otherwise specified, the so-called feature A “or” (or) or “and / or” (and / or) feature B means that A exists alone, B exists alone, or A and B exist simultaneously; the so-called feature A “and” (and) or “and” (and) or “and” (and) feature B means that A and B exist simultaneously; the so-called “including”, “containing”, “having”, “comprising” means including but not limited to this.

[0040] In addition, in this text, “preferred” or “more preferred” is used to describe optional or additional elements or features, that is, these elements or features are not necessary and may be omitted.

[0041] In addition, in this text, unless otherwise specified, a numerical value can cover a range of ±10% of this numerical value, especially a range of ±5% of this numerical value. Unless otherwise specified, a numerical range is composed of multiple sub-ranges defined by the smaller endpoint value, the smaller quartile, the median, the larger quartile, and the larger endpoint value.

[0042] The graphite and graphene dispersant of the present invention includes alkyl sulfosuccinate and polyalkylene glycol, wherein the weight ratio of alkyl sulfosuccinate to polyalkylene glycol is between 1:99 and 99:1. When applying the above graphite and graphene dispersant, water or an organic solvent can be used to dilute it to an appropriate concentration, or it can be used directly without dilution, and it is uniformly dispersed in the dispersion medium required for various applications in various ways.

[0043] The method for dispersing graphite and graphene of the present invention includes the following steps: (a) preparing the above-mentioned graphite and graphene dispersant; and (b) mixing the graphite and graphene dispersant obtained in (a) with carbon materials to disperse the carbon materials, wherein the carbon materials are graphite, graphene, or a combination thereof.

[0044] Specific examples of the graphite and graphene dispersant provided by the present invention and its application for dispersing substances are as follows:

[0045] Example 1 Application of dispersing substance: High-purity graphite powder (300 mesh).

[0046]

[0047] Conclusion: After adding the graphite and graphene dispersant of Example 1 of the present invention, the dispersion uniformity is immediately significantly improved, and the sedimentation time is significantly postponed.

[0048] Example 2 Application of dispersing substance: Flake graphite (99.9%, 40 - 60 mesh).

[0049]

[0050]

[0051] Conclusion: After adding the graphite and graphene dispersant of Example 2 of the present invention, the dispersion uniformity is immediately significantly improved, and the sedimentation time is significantly postponed.

[0052] Example 3 Dispersed substance used: Expanded graphite powder (325 mesh).

[0053]

[0054] Conclusion: After adding the graphite and graphene dispersant of Example 3 of the present invention, the dispersion uniformity is immediately significantly improved, and the sedimentation time is significantly postponed.

[0055] Example 4 Dispersed substance used: Spherical graphite (8 μm).

[0056]

[0057] Conclusion: After adding the graphite and graphene dispersant of Example 4 of the present invention, the dispersion uniformity is immediately significantly improved, and the sedimentation time is significantly postponed.

[0058] Example 5 Dispersed substance used: High-purity graphene (10,000 mesh).

[0059]

[0060] Conclusion: After adding the graphite and graphene dispersant of Example 5 of the present invention, the dispersion uniformity is immediately significantly improved, and the sedimentation time is significantly postponed.

[0061] Example 6 Dispersed substance used: High-purity graphene (>99%, 8 μm).

[0062]

[0063] Conclusion: After adding the graphite and graphene dispersant of Example 6 of the present invention, the dispersion uniformity is immediately significantly improved, and the sedimentation time is significantly prolonged.

[0064] Example 7 Substance used: Aqueous solution of high-purity graphene dispersed in aqueous polyurea.

[0065]

[0066]

[0067] Conclusion: The main applications of polyurea are in the four fields of waterproofing, anti-corrosion, anti-abrasion and surface decoration. Uniformly dispersing high-purity graphene in polyurea can improve its waterproof mechanical strength. After adding the graphite and graphene dispersant of Example 7 of the present invention, the viscosity of the aqueous polyurea solution immediately decreases significantly, the permeability increases, the dispersion is uniform, the coating is flat, and its thickness is 1 / 3 of that of the aqueous polyurea / graphene solution without adding the graphite and graphene dispersant of Example 7 of the present invention.

[0068] Example 8 Applied substance: An aqueous solution of high-purity graphene dispersed in vermiculite powder.

[0069]

[0070] Conclusion: Vermiculite powder has good thermal insulation properties. Its melting point as high as 1400 °C and density as low as 0.9 g / cm 3 make it have important applications in fireproof and heat-insulating materials. Uniformly dispersing high-purity graphene in vermiculite can improve its flame retardant effect. After adding the graphite and graphene dispersant of Example 8 of the present invention, the viscosity of the aqueous vermiculite powder solution immediately decreases significantly, the permeability increases, the dispersion is uniform, the coating is flat, and its thickness is 1 / 3 of that of the vermiculite powder / graphene aqueous solution without adding the graphite and graphene dispersant of Example 8 of the present invention.

[0071] Example 9 Applied substance: An aqueous solution of high-purity graphene dispersed in sodium lignosulfonate.

[0072]

[0073] Conclusion: Sodium lignosulfonate can be used as an admixture for concrete. As a high-efficiency concrete water reducer, it is superior to sodium lignosulfonate in performance and is suitable for projects such as culverts, dams, reservoirs, airports and highways. Uniformly dispersing high-purity graphene in sodium lignosulfonate can increase the strength of concrete. After adding the graphite and graphene dispersant of Example 9 of the present invention, the viscosity of the aqueous sodium lignosulfonate solution immediately decreases significantly, the permeability increases, the dispersion is uniform, the coating is flat, and its thickness is 1 / 3 of that of the sodium lignosulfonate / graphene aqueous solution without adding the graphite and graphene dispersant of Example 9 of the present invention. In addition, after adding the above-mentioned graphite and graphene dispersant of the present invention, the usage amount of sodium lignosulfonate can be reduced.

[0074] Compared with other technologies, the graphite and graphene dispersant proposed by the present invention has the following advantages:

[0075] 1. It does not contain any organic solvents of flammable and volatile compounds and is not a dangerous product.

[0076] 2. It does not contain any toxic substances and will not harm the health of humans and livestock.

[0077] 3. It does not contain any aromatic compounds and has excellent operational safety.

[0078] 4. It does not contain any compounds based on fluorine, silicon or phosphorus, is biodegradable, and avoids environmental pollution.

[0079] 5. It can easily disperse graphite, graphene or their combination in an aqueous solution, and has the characteristics of expanding the industrial operability and application range of graphite, graphene or their combination.

[0080] 6. The addition amount is low, which can improve the economic efficiency of the industrial application of graphite and graphene.

[0081] In summary, the graphite and graphene dispersant of the present invention has the characteristics of small usage amount, quick effect, high implementation convenience, wide application, safety and non-toxicity, environmental friendliness, and high economic efficiency.

[0082] Although the present invention has been illustrated by multiple embodiments, it should be understood that many other possible modifications and changes can be made as long as they do not deviate from the spirit of the present invention and the scope of protection requested by the claims.

[0083] The above-described specific embodiments have further detailed the purpose, technical solution and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A graphite and graphene dispersant, comprising: Alkyl sulfosuccinates; as well as Polyalkylene glycol; The weight ratio of the alkyl sulfosuccinate to the polyethylene glycol is between 1:99 and 99:

1.

2. The graphite and graphene dispersant according to claim 1, wherein: The alkyl sulfosuccinate is monoalkyl sulfosuccinate, dialkyl sulfosuccinate, polyalkyl sulfosuccinate or a combination thereof.

3. The graphite and graphene dispersant according to claim 1, wherein: The alkyl sulfosuccinate is an alkyl sulfosuccinate having the following chemical formula: CH2—COOR1 ︱ CH—COOR2 ︱ SO3Na Wherein, R1 and R2 are each an alkyl group.

4. The graphite and graphene dispersant according to claim 3, wherein: R1 and R2 are each an alkyl group having 4 to 18 carbon atoms.

5. The graphite and graphene dispersant according to claim 1, wherein: The polyalkylene glycol has the following chemical formula: The ratio of n to m is between 1 and 10, and the molecular weight of the polyalkylene glycol is between 500 and 6000.

6. The graphite and graphene dispersant according to claim 1, wherein: The weight ratio of the alkyl sulfosuccinate to the polyethylene glycol is between 1:9 and 9:

1.

7. The graphite and graphene dispersant according to claim 1, wherein: The graphite and graphene dispersant are added to a dispersion medium in an amount ranging from 0.01 wt % to 10 wt % of the weight of the dispersion medium.

8. The graphite and graphene dispersant according to claim 7, wherein: The dispersion medium is water, organic solvent, resin, latex, plastic, paint, concrete, ceramic, asphalt, oil, metal material or a combination thereof.

9. The graphite and graphene dispersant according to claim 1, wherein: The graphite and graphene dispersant do not contain any flammable organic solvent.

10. The graphite and graphene dispersant according to claim 1, wherein: The graphite and graphene dispersant do not contain any fluorine, silicon or phosphorus compounds.

11. The graphite and graphene dispersant according to claim 1, wherein: The graphite and graphene dispersant do not contain any aromatic compounds.

12. The graphite and graphene dispersant according to claim 1, wherein: The graphite and graphene dispersants are used to manufacture solid or liquid graphite materials, graphene materials and related nano-carbon materials that are easily dispersed in water.

13. A method for dispersing graphite and graphene, comprising the following steps: (a) preparing a graphite and graphene dispersant as described in any one of claims 1 to 12; and (b) mixing the graphite and graphene dispersant obtained in (a) with a carbon material to disperse the carbon material, wherein the carbon material is graphite, graphene or a combination thereof.

14. The method according to claim 13, wherein: The method uses a liquid phase exfoliation method and a mechanical exfoliation method to disperse the graphite, the graphene or a combination thereof.

15. The method according to claim 13, wherein: The graphite, the graphene or a combination thereof is used for conducting electricity, dissipating heat, flame retardancy, corrosion resistance, waterproofing, strengthening, adsorption, antibacterial or a combination thereof.

16. The method according to claim 13, wherein: The graphite, the graphene or a combination thereof is applied to biomedical liquids.

17. The method according to claim 13, wherein: The graphite, the graphene or a combination thereof is used to treat radioactive discharge liquid from a nuclear power plant.

18. The method according to any one of claims 13 to 17, wherein: The graphite and graphene dispersant are applied by mixing, dispersing, spraying, coating, extruding, ball milling or a combination thereof.

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