A kind of dispersed and stable soluble onion carbon powder and preparation method thereof

Abstract

The invention discloses a dispersed and stable soluble onion carbon powder and a preparation method thereof, and relates to the technical field of carbon nanomaterial preparation. The preparation steps of the dispersed and stable soluble onion carbon powder are as follows: step S1, using hydrocarbon as a carbon source, and step S2, putting the hydrocarbon into a tube furnace and heating it at high temperature to evaporate and burn it. The invention uses a one-step combustion method, and temperature can effectively control the synthesis and growth of onion carbon nanoparticles, so as to obtain a uniformly dispersed onion carbon powder, without the need for additional purification processes and functional modification treatments. Then, the uniformly dispersed onion carbon powder is mixed with a polar organic solvent in an experiment, and it is proved that the uniformly dispersed onion carbon powder has high solubility and good dispersibility, which is conducive to broadening its application range and improving the performance of the onion carbon powder in various applications.

Description

Technical Field

[0001] The invention relates to the technical field of carbon nano material preparation, in particular to a dispersed and stable soluble onion carbon powder and a preparation method thereof. Background Art

[0002] Onion carbon is another important member of the carbon family after fullerene and carbon nanotubes. Ideal onion carbon is composed of concentric fullerene balls of different sizes, with a "Russian doll" structure, showing an orderly arrangement of atoms at the nanoscale, with an adjacent layer spacing of about 0.34nm, and a disordered state on the macro scale. Onion carbon molecules are randomly distributed and cannot form a molecular crystal structure similar to C60. The special atomic arrangement makes onion carbon have excellent physical properties, such as high specific surface area, thermal conductivity, thermal stability, chemical stability, and environmental friendliness, so that it has broad application prospects in lubrication, catalysis, lithium-ion batteries, supercapacitors, electromagnetic shielding, biomedicine and other fields.

[0003] Onion carbon was first discovered in carbon films prepared by vacuum deposition and reported by Professor Iijima in 1980. In 1992, Professor Ugarte used electron beam irradiation to report the synthesis of onion carbon again and described its atomic structure. Since then, the research on the preparation method of onion carbon with high purity, high yield and uniform particle size has become the focus of long-term attention of scientific and technological personnel in this field. At present, the methods for preparing onion carbon mainly include arc discharge method, electron beam irradiation method, laser irradiation method, chemical vapor deposition method, nanodiamond annealing method, carbon ion implantation method, ball milling method, detonation synthesis method, hydrothermal carbonization method, etc. Arc discharge method and electron beam irradiation method are the earliest proposed methods for preparing onion carbon. Arc discharge method refers to the formation of onion carbon by cooling and reorganization of carbon-containing precursors after sublimation and cracking under the action of electric current, while electron beam irradiation method is mainly used for in-situ analysis of the formation process of onion carbon under transmission electron microscopy. The onion carbon prepared by this method is generally of low purity, contains a large amount of impurities such as amorphous carbon and carbon nanotubes, and has a low yield, which is not suitable for mass production. The laser irradiation method uses a high-energy laser beam to irradiate a carbon-containing precursor, such as carbon black, nanodiamonds, etc., to cause a phase change to synthesize onion carbon. Its main problems are high energy consumption, impurity phases, and low yield. The onion carbon prepared by the chemical vapor deposition method is often wrapped with metal ions. The onion carbon center prepared by nanodiamond annealing contains unconverted nanodiamond cores, so it is difficult to purify and it is difficult to obtain high-purity onion carbon. In addition, carbon ion implantation, ball milling, detonation synthesis, hydrothermal carbonization, etc. also face problems such as expensive equipment, low yield, and difficulty in purification. In addition, the onion carbon prepared by the above methods has poor solubility and dispersibility in organic solvents, requires additional functionalization treatment processes, increases the process flow, and further limits large-scale production.

[0004] The existing onion carbon powder preparation method has the following defects:

[0005] 1. Patent document US08992880B2 discloses a method for manufacturing onion-like carbon. However, in the above document, chemical vapor deposition (CVD) is used to make onion-like carbon, and a catalyst is required in the preparation process. As a result, the prepared onion carbon contains metal ions, which requires additional subsequent pickling and purification processes;

[0006] 2. Patent document JPWO2012168993A1 discloses a method for producing onion-like carbon. However, the application scope of the onion-like carbon obtained in the above document is relatively small, so the obtained onion-like carbon is not conducive to further research and development and application;

[0007] 3. Patent document KR101853727B1 discloses onion-like carbon derived from nanodiamond and its preparation method, but the production qualification rate and purity of onion-like carbon obtained in the above document are low, so it does not have the technical problems of large-scale production;

[0008] 4. Patent document CN105833797B discloses a high-temperature and high-pressure preparation method for nano-onion carbon. However, the carbon source and high-temperature and high-pressure equipment used in the above document to obtain nano-onion carbon consume high energy, the equipment is expensive, and the preparation process is relatively complicated, so there is a technical problem of poor economic benefits. Summary of the invention

[0009] The object of the present invention is to provide a dispersed and stable soluble onion carbon powder and a preparation method thereof, so as to solve the technical problems raised in the above background technology.

[0010] To achieve the above object, the present invention provides the following technical solution: a method for preparing a dispersed and stable soluble onion carbon powder, wherein the steps for preparing the dispersed and stable soluble onion carbon powder are as follows:

[0011] Step S1, using hydrocarbon as a carbon source;

[0012] Step S2, placing hydrocarbons in a tube furnace and heating them at high temperature to evaporate and burn them;

[0013] Step S3, using an ash collection device to collect the ash generated after the combustion of hydrocarbons;

[0014] Step S4, placing the collected ashes into a vacuum tube furnace for high temperature heat treatment to obtain pure onion carbon powder;

[0015] Step S5: Conduct necessary testing and analysis on the collected onion carbon powder to ensure that its quality and performance meet the requirements.

[0016] Preferably, the hydrocarbon raw material used in step S1 is one of naphthalene or paraffin, preferably naphthalene, and its purity is >95%.

[0017] Preferably, the tubular furnace in step S2 is a dual-temperature zone tubular furnace, the heating temperature of the first temperature zone is 300°C-1000°C, the heating temperature of the second temperature zone is 600°C-1500°C, and the heating rates of the first temperature zone and the second temperature zone are both 5°C / min-8°C / min.

[0018] Preferably, the equipment for high temperature heat treatment in step S4 is a vacuum tube furnace, the high temperature heat treatment temperature of the vacuum tube furnace is 200°C-500°C, the high temperature heat treatment time is 2h-24h, and the high temperature heat treatment heating rate is 5°C / min.

[0019] Preferably, the onion carbon powder collected in step S5 is a regular sphere with a particle size of 30nm-300nm. 0.1g of the collected onion carbon powder is taken out and added to 10g of glycerol, 10g of polyethylene glycol and 10g of ethanol respectively to prepare a 1%wt solution, and ultrasonically vibrated for 2h and then allowed to stand to obtain the dissolution effect of the onion carbon powder in different solvents.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention uses a one-step combustion method to effectively control the synthesis and growth of onion carbon nanoparticles by temperature, thereby obtaining uniformly dispersed onion carbon powder without the need for additional purification processes and functional modification treatments. Then, the uniformly dispersed onion carbon powder is mixed with a polar organic solvent, and it is proved that the uniformly dispersed onion carbon powder has high solubility and dispersion stability, which is conducive to broadening its application range and improving the performance of the onion carbon powder in various applications;

[0022] 2. The onion carbon powder prepared by the above preparation method has good solubility and dispersion stability, and can be widely used in multiple fields such as energy, environment, biomedicine and electronic information, which is conducive to providing a broad application space for further research and application of onion carbon powder;

[0023] 3. The present invention precisely controls the temperature and reaction time during the preparation process, so the preparation process is simple, the onion carbon nanoparticle production efficiency and production qualification rate are high, and the prepared onion carbon powder has a high purity, so it has the effect of large-scale production;

[0024] 4. The present invention selects hydrocarbons as carbon sources, and a dual-zone tubular furnace and a vacuum tubular furnace as heating devices. The dual-zone tubular furnace can independently control the temperatures of two zones, thereby reducing ineffective heat transfer and loss, and improving energy efficiency, thereby helping to reduce complexity and cost in the preparation process and improve economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the workflow of the present invention;

[0026] Figure 2 The X-ray diffraction pattern of the onion carbon powder prepared by the present invention;

[0027] Figure 3 This is an X-ray photoelectron spectrum of the onion carbon powder prepared by the present invention;

[0028] Figure 4 The scanning electron microscope image and the transmission electron microscope image of the onion carbon powder prepared by the present invention;

[0029] Figure 5 This is a high-resolution transmission electron microscopy image of the onion carbon powder prepared by the present invention;

[0030] Figure 6 This is the dissolution diagram of the onion carbon powder prepared in the present invention in different solvents. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in 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.

[0032] Example 1: Please refer to Figure 1 The present invention provides an embodiment: a method for preparing a dispersed and stable soluble onion carbon powder. The preparation steps of the dispersed and stable soluble onion carbon powder are as follows:

[0033] Step S1, using hydrocarbon as a carbon source;

[0034] Step S2, placing hydrocarbons in a tube furnace and heating them at high temperature to evaporate and burn them;

[0035] Step S3, using an ash collection device to collect the ash generated after the combustion of hydrocarbons;

[0036] Step S4, placing the collected ashes into a vacuum tube furnace for high temperature heat treatment to obtain pure onion carbon powder;

[0037] Step S5, performing necessary testing and analysis on the collected onion carbon powder to ensure that its quality and performance meet the requirements;

[0038] The naphthalene raw material used in step S1 has a purity of >95%;

[0039] The tubular furnace in step S2 is a dual-temperature zone tubular furnace, the heating temperature of the first temperature zone is 500° C., the heating temperature of the second temperature zone is 800° C., and the heating rates of the first temperature zone and the second temperature zone are both 6.5° C. / min;

[0040] The equipment for high temperature heat treatment in step S4 is a vacuum tube furnace, the high temperature heat treatment temperature of the vacuum tube furnace is 350°C, the high temperature heat treatment time is 12h, and the high temperature heat treatment heating rate is 5°C / min;

[0041] The onion carbon powder collected in step S5 is a regular sphere with an average particle size of 50 nm. 0.1 g of the collected onion carbon powder is taken out and added to 10 g of glycerol, 10 g of polyethylene glycol, and 10 g of ethanol respectively to prepare a 1% wt solution, and ultrasonically vibrated for 2 hours and then allowed to stand to obtain the dissolution effect of the onion carbon powder in different solvents.

[0042] Example 2: Please refer to Figure 1 , an embodiment provided by the present invention: the specific implementation is the same as that of embodiment 1, except that: the naphthalene raw material is used in step S1, and its purity is >95%;

[0043] The tubular furnace in step S2 is a dual-temperature zone tubular furnace, the heating temperature of the first temperature zone is 300° C., the heating temperature of the second temperature zone is 600° C., and the heating rates of the first temperature zone and the second temperature zone are both 5° C. / min;

[0044] The equipment for high temperature heat treatment in step S4 is a vacuum tube furnace, the high temperature heat treatment temperature of the vacuum tube furnace is 200°C, the high temperature heat treatment time is 2h, and the high temperature heat treatment heating rate is 5°C / min;

[0045] The onion carbon powder collected in step S5 is a regular sphere with an average particle size of 55 nm. 0.1 g of the collected onion carbon powder is taken out and added to 10 g of glycerol, 10 g of polyethylene glycol, and 10 g of ethanol respectively to prepare a 1% wt solution, and ultrasonically vibrated for 2 hours and then allowed to stand to obtain the dissolution effect of the onion carbon powder in different solvents.

[0046] Example 3: Please refer to Figure 1, an embodiment provided by the present invention: the specific implementation is the same as that of embodiment 1, except that: the naphthalene raw material is used in step S1, and its purity is >95%;

[0047] The tubular furnace in step S2 is a dual-temperature zone tubular furnace, the heating temperature of the first temperature zone is 1000° C., the heating temperature of the second temperature zone is 1500° C., and the heating rates of the first temperature zone and the second temperature zone are both 8° C. / min;

[0048] The equipment for high temperature heat treatment in step S4 is a vacuum tube furnace, the high temperature heat treatment temperature of the vacuum tube furnace is 500°C, the high temperature heat treatment time is 24h, and the high temperature heat treatment heating rate is 5°C / min;

[0049] The onion carbon powder collected in step S5 is a regular sphere with an average particle size of 240 nm. 0.1 g of the collected onion carbon powder is taken out and added to 10 g of glycerol, 10 g of polyethylene glycol, and 10 g of ethanol respectively to prepare a 1% wt solution, and ultrasonically vibrated for 2 hours and then allowed to stand to obtain the dissolution effect of the onion carbon powder in different solvents.

[0050] Example 4: Please refer to Figure 1 , an embodiment provided by the present invention: the specific implementation is the same as that of embodiment 1, except that: the naphthalene raw material is used in step S1, and its purity is >95%;

[0051] The tubular furnace in step S2 is a dual-temperature zone tubular furnace, the heating temperature of the first temperature zone is 800° C., the heating temperature of the second temperature zone is 800° C., and the heating rates of the first temperature zone and the second temperature zone are both 8° C. / min;

[0052] The equipment for high temperature heat treatment in step S4 is a vacuum tube furnace, the high temperature heat treatment temperature of the vacuum tube furnace is 400°C, the high temperature heat treatment time is 10h, and the high temperature heat treatment heating rate is 5°C / min;

[0053] The onion carbon powder collected in step S5 is a regular sphere with an average particle size of 66 nm. 0.1 g of the collected onion carbon powder is taken out and added to 10 g of glycerol, 10 g of polyethylene glycol, and 10 g of ethanol respectively to prepare a 1% wt solution, and ultrasonically vibrated for 2 hours and then allowed to stand to obtain the dissolution effect of the onion carbon powder in different solvents.

[0054] Example 5: Please refer to Figure 1 , an embodiment provided by the present invention: the specific implementation is the same as that of embodiment 1, except that: the paraffin raw material is used in step S1, and its purity is >95%;

[0055] The tubular furnace in step S2 is a dual-temperature zone tubular furnace, the heating temperature of the first temperature zone is 500° C., the heating temperature of the second temperature zone is 700° C., and the heating rates of the first temperature zone and the second temperature zone are both 6.5° C. / min;

[0056] The equipment for high temperature heat treatment in step S4 is a vacuum tube furnace, the high temperature heat treatment temperature of the vacuum tube furnace is 350°C, the high temperature heat treatment time is 12h, and the high temperature heat treatment heating rate is 5°C / min;

[0057] The onion carbon powder collected in step S5 is a regular sphere with an average particle size of 40 nm. 0.1 g of the collected onion carbon powder is taken out and added to 10 g of glycerol, 10 g of polyethylene glycol, and 10 g of ethanol respectively to prepare a 1% wt solution, and ultrasonically vibrated for 2 hours and then allowed to stand to obtain the dissolution effect of the onion carbon powder in different solvents.

[0058] Example 6: Please refer to Figure 1 , an embodiment provided by the present invention: the specific implementation is the same as that of embodiment 1, except that: the paraffin raw material is used in step S1, and its purity is >95%;

[0059] The tubular furnace in step S2 is a dual-temperature zone tubular furnace, the heating temperature of the first temperature zone is 600° C., the heating temperature of the second temperature zone is 1000° C., and the heating rates of the first temperature zone and the second temperature zone are both 5° C. / min;

[0060] The equipment for high temperature heat treatment in step S4 is a vacuum tube furnace, the high temperature heat treatment temperature of the vacuum tube furnace is 200°C, the high temperature heat treatment time is 24h, and the high temperature heat treatment heating rate is 5°C / min;

[0061] The onion carbon powder collected in step S5 is a regular sphere with an average particle size of 120 nm. 0.1 g of the collected onion carbon powder is taken out and added to 10 g of glycerol, 10 g of polyethylene glycol, and 10 g of ethanol respectively to prepare a 1% wt solution, and ultrasonically vibrated for 2 hours and then allowed to stand to obtain the dissolution effect of the onion carbon powder in different solvents.

[0062] Comparative Example 1: Preparation of onion carbon powder by arc discharge method:

[0063] S1. Under specific conditions, onion carbon with an average particle size of a specific size is prepared by arc discharge;

[0064] S2, placing the prepared onion carbon in a muffle furnace and burning it at a specific temperature for a period of time;

[0065] S3, soaking the burned onion carbon with dilute hydrochloric acid to remove impurities;

[0066] S4. Purified onion carbon is obtained by repeated centrifugation and drying.

[0067] Comparative Example 2: Preparation of onion carbon powder by laser irradiation:

[0068] S1. It is also necessary to select and pre-treat the carbon source material to ensure that it is suitable for the laser irradiation process;

[0069] S2. Place the carbon source in a laser irradiation device and irradiate the carbon source with a high-energy laser beam. During the irradiation process, the energy density, wavelength and irradiation time of the laser need to be precisely controlled to ensure that the carbon source undergoes a phase change under high temperature and high pressure to form onion carbon nanoparticles;

[0070] S3. After the irradiation, the product is collected and subjected to necessary post-treatment, such as washing and drying, to remove impurities and optimize the performance of the onion carbon.

[0071] Comparative Example 3: Preparation of onion carbon powder by chemical vapor deposition method:

[0072] S1. Select appropriate substrate materials, such as silicon wafers, metal sheets, etc., and clean them. At the same time, prepare the chemical vapor deposition reactor and ensure that it is airtight;

[0073] S2, introducing carbon-containing gas into the reactor and controlling the flow rate and concentration of the gas;

[0074] S3, heating the reactor to decompose the carbon-containing gas at high temperature and deposit it on the substrate, and promoting the formation of onion-like carbon nanostructures by controlling parameters such as reaction temperature, pressure and time;

[0075] S4. After the deposition is completed, the reactor is cooled to room temperature and the onion carbon products attached to the substrate are collected.

[0076] Comparative Example 4: Preparation of onion carbon powder by nanodiamond annealing method:

[0077] S1. In an argon atmosphere, the nano-diamond powder is placed in a tube furnace and heated to a specific temperature and maintained for a period of time;

[0078] S2, cooling down to room temperature at a certain cooling rate;

[0079] S3, recovering the onion carbon powder.

[0080] Test result 1: Solubility and dispersion stability of onion carbon powder in polar organic solvents:

[0081] The onion carbon powder collected in Examples 1-6 and Comparative Examples 1-4 was selected, and 0.1 g of the onion carbon powder was taken out and added to 10 g of glycerol, 10 g of polyethylene glycol, and 10 g of ethanol respectively to prepare a 1% wt solution. The solution was ultrasonically vibrated for 2 hours and then allowed to stand to determine the solubility and dispersion stability of the onion carbon powder in different solvents (the effects of solubility and dispersion stability are represented by numbers from 0 to 100, and the larger the number, the better the performance).

[0082] Solubility Dispersion stability Example 1 89 88 Example 2 88 79 Example 3 45 55 Example 4 90 81 Example 5 87 92 Example 6 51 43 Comparative Example 1 5 3 Comparative Example 2 8 10 Comparative Example 3 7 5 Comparative Example 4 9 4

[0083] Furthermore, through a one-step combustion method, the synthesis and growth of onion carbon nanoparticles can be effectively controlled by temperature, thereby obtaining a uniformly dispersed onion carbon powder without the need for additional purification processes and functional modification treatments. Then, the uniformly dispersed onion carbon powder is mixed with a polar organic solvent, and it is proved that the uniformly dispersed onion carbon powder has high solubility and dispersion stability, which is conducive to broadening its application range and improving the performance of the onion carbon powder in various applications.

[0084] The onion carbon powder prepared by the above preparation method has good solubility and dispersion stability, and can be widely used in multiple fields such as energy, environment, biomedicine and electronic information, which is conducive to providing a broad application space for further research and application of onion carbon powder;

[0085] Precisely controlling the temperature during the preparation process is helpful to ensure the solubility and dispersion stability of onion carbon powder in different solvents.

[0086] Test result 2: Production qualification rate of onion carbon powder and purity of onion carbon powder:

[0087] The onion carbon powder collected in Examples 1-6 and Comparative Examples 1-4 was selected to detect the production qualification rate and the purity of the onion carbon powder.

[0088] Production qualification rate % purity% Example 1 90 96 Example 2 88 97 Example 3 83 80 Example 4 88 98 Example 5 91 99 Example 6 92 96 Comparative Example 1 54 69 Comparative Example 2 46 53 Comparative Example 3 48 57 Comparative Example 4 45 62

[0089] Furthermore, by precisely controlling the temperature and reaction time during the preparation process, the preparation process is simple, the onion carbon nanoparticle production efficiency and production qualification rate are high, and the prepared onion carbon powder has a high purity, so it has the effect of large-scale production;

[0090] By selecting hydrocarbon as the carbon source, a dual-temperature zone tubular furnace and a vacuum tubular furnace as the heating apparatus, the dual-temperature zone tubular furnace can independently control the temperature of the two zones, thereby reducing the ineffective transfer and loss of heat, improving the energy utilization efficiency, and thus helping to reduce the complexity and cost of the preparation process and improve the economic benefits;

[0091] Working principle: by utilizing the incomplete combustion of hydrocarbons, the particle size, morphology, and surface functional groups of onion carbon can be effectively regulated by controlling the temperature, without the need for additional purification processes and functional modification treatments. Then, the evenly dispersed onion carbon powder is mixed with a polar organic solvent to prove that it has good solubility and dispersion stability, which is beneficial to broaden its application range and improve the performance of onion carbon powder in various applications. The onion carbon powder prepared by the above preparation method has good solubility and dispersion stability, so it can be widely used in energy, environment, biomedicine, electronic information and other fields. The invention relates to a novel onion carbon nanoparticle preparation method, which provides a broad application space for further research and application of onion carbon powder. By precisely controlling the temperature and reaction time in the preparation process, the production efficiency and qualified rate of onion carbon nanoparticles are improved, and the prepared onion carbon powder has a high purity, so it can be mass-produced. By selecting hydrocarbons as carbon sources, dual-temperature zone tubular furnaces and vacuum tube furnaces as heating devices, the dual-temperature zone tubular furnace can independently control the temperatures of the two zones, which reduces the ineffective transfer and loss of heat, and can improve the efficiency of energy utilization, thereby reducing the complexity and cost of the preparation process and improving the economic benefits.

[0092] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

Claims

1. A method for preparing a dispersed and stable soluble onion carbon powder, characterized in that: It consists of the following preparation steps: Step S1, using hydrocarbon as a carbon source; The hydrocarbon raw material used in step S1 is one of naphthalene or paraffin; Step S2, placing hydrocarbons in a tube furnace and heating them at high temperature to evaporate and burn them; Step S3, using an ash collection device to collect the ash generated after the combustion of hydrocarbons; Step S4, placing the collected ashes into a vacuum tube furnace for high temperature heat treatment to obtain pure onion carbon powder; Step S5, the collected onion carbon powder is a regular sphere with a particle size of 30nm-300nm; The tubular furnace in step S2 is a dual-temperature zone tubular furnace, the heating temperature of the first temperature zone is 300°C-1000°C, the heating temperature of the second temperature zone is 600°C-1500°C, and the heating rates of the first temperature zone and the second temperature zone are both 5°C / min-8°C / min; The equipment for high temperature heat treatment in step S4 is a vacuum tube furnace, the high temperature heat treatment temperature of the vacuum tube furnace is 200°C-500°C, the high temperature heat treatment time is 2h-24h, and the high temperature heat treatment heating rate is 5°C / min.

2. The method for preparing a dispersed and stable soluble onion carbon powder according to claim 1, characterized in that: The hydrocarbon raw material used in step S1 is naphthalene, and its purity is greater than 95%.

3. The method for preparing a dispersed and stable soluble onion carbon powder according to claim 1, characterized in that: 0.1 g of the onion carbon powder collected in step S5 was taken out and added to 10 g of glycerol, 10 g of polyethylene glycol, and 10 g of ethanol respectively to prepare a 1%wt solution, and ultrasonically vibrated for 2 hours and then allowed to stand to obtain the dissolution effect of the onion carbon powder in different solvents.

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