KR102015119B1 - Method of Preparing Heteroatom-Doped Carbon Materials Using Spent Coffee Grounds and Application of Electrode Materials Thereof - Google Patents

Abstract

The present invention provides a nitrogen-doped carbon material through activation treatment of various waste coffee grounds raw materials, ranging from ordinary coffee grounds, which are household waste, to coffee grounds from which lipids or biodiesel are extracted. Preparation of hetero-doped carbonaceous material using waste coffee which can be used as electrode material of fuel cell, supercapacitor or redox flow battery by preparing carbon material doped with boron and nitrogen at the same time by doping boron precursor It is about a method.

Description

Method of Preparing Heteroatom-Doped Carbon Materials Using Spent Coffee Grounds and Application of Electrode Materials Thereof}

The present invention relates to a method for producing a carbon material doped with a heterogeneous element of boron or nitrogen using waste coffee grounds, and more particularly, extracting lipids or biodiesel from ordinary coffee grounds, which are household wastes. It can be used as an electrode material by synthesizing carbon materials doped with nitrogen or doped with boron and nitrogen at the same time by activating various waste coffee raw materials such as coffee grounds. It relates to a method for producing a carbon material using spent coffee grounds.

As Korean's diet gradually becomes westernized, coffee is the most rapidly consumed ingredient. As it increased, coffee grounds, which account for 99.8% of coffee beans, also increased exponentially. According to the Ministry of Environment's press release (distributed on April 12, 2016), the amount of coffee grounds discharged annually in Korea is about 103,000 tons. Conventional treatment method is to landfill by mixing in a pay-as-you-go bag together with the general waste, which incurs economic and social costs such as waste of pay-as-you-go bag and landfill saturation.

The most widely used solution to this problem is the use of compost. Composts from livestock manure have the disadvantage of producing odors, but compost from coffee grounds is free from this problem. Furthermore, it is suitable as an eco-friendly compost because it has ingredients such as nitrogen, phosphorus and potassium.

In addition, coffee grounds contain about 15% of the lipids, which is enough to obtain biomass fuel. Biodiesel can be produced through solvent extraction and can also be used in the form of bio pellets.

However, both of these approaches have common limitations. After being used as fertilizers and biomass, respectively, residues in the form of waste remain. There is a problem to minimize the cost of landfill, but there is a problem that can not be a fundamental solution to complete disposal of coffee grounds.

Accordingly, the present inventors have made diligent efforts to find an economical method of recycling waste coffee, and as a result, when activators are added to various waste coffee raw materials, ranging from general coffee grounds, which are household waste, to coffee grounds from which lipids or biodiesel are extracted, A carbon material doped with a heterogeneous element of boron and nitrogen having a high specific surface area was prepared, and it was confirmed that it can be used as an electrode material of a fuel cell electrode, a supercapacitor and a redox flow cell, and completed the present invention. .

Republic of Korea Patent Registration No. 10-1176969 (2012.08.20. Registration) Republic of Korea Patent No. 10-0259546 (registered on March 23, 2000) Japanese Patent Laid-Open No. 2005-075686 (published Jan. 1, 2003)

It is an object of the present invention to use semi-permanent utilization of coffee grounds from a variety of waste coffee raw materials, ranging from general coffee grounds, which are household wastes, to coffee grounds from which lipids or biodiesel are extracted, and nitrogen and boron that can completely dispose of coffee grounds. It is to provide a method for producing a carbon material doped with different elements such as.

Another object of the present invention is to provide the application of nitrogen-doped or boron and nitrogen-doped carbon materials produced by the manufacturing method to electrode materials of fuel cells, supercapacitors and redox flow batteries having excellent performance. There is.

In order to achieve the above object, the present invention (a) waste coffee grounds selected from the group consisting of potassium hydroxide (KOH), sodium hydroxide (NaOH), phosphoric acid (H ₃ PO ₄ ) and zinc chloride (ZnCl ₂ ) Mixing the above aqueous activator solution to obtain a slurry; (b) drying the slurry of (a) and heat-treating the furnace in which an inert gas is introduced to obtain activated carbon; And (c) provides a method for producing a hetero-element doped carbon material using waste coffee comprising the step of purifying and drying the activated carbon of (b).

The present invention also provides (a) waste coffee grounds containing at least one aqueous activator solution selected from the group consisting of potassium hydroxide (KOH), sodium hydroxide (NaOH), phosphoric acid (H ₃ PO ₄ ) and zinc chloride (ZnCl ₂ ). Mixing to obtain a slurry; (b) drying the slurry of (a) and heat-treating the furnace in which an inert gas is introduced to obtain activated carbon; (c) purifying and drying the activated carbon of (b), and then adding and mixing the boron precursor to obtain a slurry; (d) drying the slurry of (c) and heat-treating in a heating furnace into which gas is introduced to obtain activated carbon; And (e) purifying the activated carbon of (d) to provide a method for producing hetero-doped carbon material using waste coffee.

The present invention also provides a heterogeneous element-doped carbon material of 1) nitrogen-doped porous carbon material and 2) boron and nitrogen co-doped porous carbon material prepared by the above method.

The present invention also provides an electrode material comprising 1) a nitrogen doped porous carbon material and / or 2) a boron and nitrogen co-doped porous carbon material.

The manufacturing method according to the present invention utilizes a variety of waste coffee raw materials, ranging from general coffee grounds, which are household wastes, to coffee grounds from which lipids or biodiesel are extracted, to be used as high-performance battery electrode materials, and thus, fertilizers that have been used to treat conventional coffee grounds. And semi-permanent processing beyond the one-offs of biomass and at the same time create economic value. In addition, when carbon dioxide is used when doping boron, it may contribute to carbon dioxide reduction due to carbon material conversion by a carbon dioxide reducing agent.

1 is a schematic diagram schematically showing a manufacturing process for performing Examples 1 and 2 of the present invention.
Figure 2 is a photograph of the manufacturing process of the activated carbon in Example 1.
3 is a view showing a nitrogen adsorption isotherm graph of the specific surface area analysis of activated carbon according to Example 1.
4 is a view showing a micropore distribution diagram of the specific surface area analysis of activated carbon according to Example 1.
5 is a scanning electron microscope photograph of activated carbon according to Example 1. FIG.
6 is a graph showing CV graphs of activated carbons according to Examples 1 and 2. FIG.
7 is a graph showing the performance and durability of the activated carbon according to Examples 1 and 2.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In general, the nomenclature used herein is well known and commonly used in the art.

In the present invention, the carbon material produced by activating a variety of waste coffee raw materials from the general coffee grounds, which are household wastes, to coffee grounds from which lipids or biodiesel are extracted, and the doping of boron or nitrogen is used as fuel electrodes, supercapacitors and res. It was confirmed that it can be used as an electrode of a dox flow battery.

Accordingly, the present invention provides at least one activated coffee waste selected from the group consisting of (a) potassium hydroxide (KOH), sodium hydroxide (NaOH), phosphoric acid (H ₃ PO ₄ ) and zinc chloride (ZnCl ₂ ). Mixing the first aqueous solution to obtain a slurry; (b) drying the slurry of (a) and heat-treating the furnace in which an inert gas is introduced to obtain activated carbon; And (c) relates to a method for producing a hetero-element doped carbon material using waste coffee comprising the step of purifying and drying the activated carbon of (b).

In another aspect of the present invention (a) one or more activator aqueous solution selected from the group consisting of waste coffee grounds (KOH), sodium hydroxide (NaOH), phosphoric acid (H ₃ PO ₄ ) and zinc chloride (ZnCl ₂ ) Mixing to obtain a slurry; (b) drying the slurry of (a) and heat-treating the furnace in which an inert gas is introduced to obtain activated carbon; (c) purifying and drying the activated carbon of (b), and then adding and mixing the boron precursor to obtain a slurry; (d) drying the slurry of (c) and heat-treating in a heating furnace into which gas is introduced to obtain activated carbon; And (e) purifying the activated carbon of (d) to a method for producing boron and nitrogen doped carbon materials using waste coffee.

The present invention relates to a process for manufacturing a carbon material using waste coffee grounds (spent coffee grounds) as a raw material and to a case of applying the carbon material produced as a battery electrode material. According to an embodiment of the present invention, activated carbon may be prepared by applying potassium hydroxide activation method (KOH activation) to various waste coffee raw materials, ranging from general coffee grounds, which are household wastes, to coffee grounds from which lipids or biodiesel are extracted. Can be. The activated carbon produced through the present invention has a high specific surface area and a structure doped with nitrogen and boron, and thus can be used as a high quality electrode material for a battery.

Due to the nature of coffee grounds, organic waste, there is a possibility of decay, such as the formation of mold, depending on the storage method. It is possible to produce a certain quality of activated carbon regardless of the raw material decay. Ultimately, waste coffee grounds can be used to produce high performance electrode materials to create economic value.

The present invention introduces potassium hydroxide activation to produce high quality activated carbon from coffee grounds. Potassium hydroxide activation is a kind of chemical activation and is a very effective treatment for inducing a porous structure.

The manufacturing method proposed by the present invention may include the following steps:

(a) a slurry by drying the waste coffee grounds and mixing one or more aqueous activator solutions selected from the group consisting of potassium hydroxide (KOH), sodium hydroxide (NaOH), phosphoric acid (H ₃ PO ₄ ) and zinc chloride (ZnCl ₂ ) Obtaining; (b) drying the slurry of (a) and heat-treating the furnace in which an inert gas is introduced to obtain activated carbon; (c) purifying and drying the activated carbon of (b), and then adding and mixing the boron precursor to obtain a slurry; (d) drying the slurry of (c) and heat-treating in a heating furnace into which gas is introduced to obtain activated carbon; And (e) purifying the activated carbon of (d).

The recipe proposed by the present invention is applicable even when coffee grounds are not dried: (a) waste coffee grounds containing water are potassium hydroxide (KOH), sodium hydroxide (NaOH), phosphoric acid (H ₃ PO ₄ ) and Mixing at least one aqueous activator solution selected from the group consisting of zinc chloride (ZnCl ₂ ) to obtain a slurry; (b) drying the slurry of (a) and heat-treating the furnace in which an inert gas is introduced to obtain activated carbon; (c) purifying and drying the activated carbon of (b), and then adding and mixing the boron precursor to obtain a slurry; (d) drying the slurry of (c) and heat-treating in a heating furnace into which gas is introduced to obtain activated carbon; And (e) purifying the activated carbon of (d).

The preparation method according to one preferred embodiment of the present invention is as follows:

(a) drying the coffee grounds as a raw material and mixing the dried coffee grounds with an aqueous potassium hydroxide solution to obtain a slurry; (b) heat treating the partially or totally dried slurry in a furnace through which nitrogen flows; (c) purifying the resultant activated carbon with hydrochloric acid, water, ethanol and the like; (d) drying the activated carbon after purification; (e) Completion of activated carbon doped with nitrogen.

or

(a) mixing coffee grounds with water and aqueous potassium hydroxide solution; (b) drying the slurry mixed in (a) and heat-treating the partially or fully dried slurry in a furnace through which nitrogen flows; (c) purifying the resultant activated carbon with hydrochloric acid, water, ethanol and the like, and drying; (d) completion of nitrogen doped activated carbon.

This recipe is a technique that can be applied to coffee grounds after extraction of lipids or biodiesel as well as general coffee grounds. The step of producing activated carbon using this as the raw material is the same as the above step.

Due to the nature of the coffee waste, which is an organic waste, it is possible to produce decayed raw materials such as mold. Even in the case of spoiled raw materials, the above manufacturing process is applicable.

In the group consisting of benzene, xylene, chloroform, hexane, ethyl acetate, methanol, ethanol and cyclohexane in general waste coffee grounds or waste coffee grounds generated after coffee beverage production, the coffee grounds used in step (a) of the present invention It may be waste coffee dregs generated after extracting a lipid or extracting biodiesel through a transduction reaction using one or more selected organic solvents or steam. That is, it includes coffee grounds that have undergone lipid or biodiesel extraction as well as common coffee grounds in a conventional sense. In addition, it can be used as a raw material in the manufacturing process irrespective of the corruption that may occur due to the nature of the organic waste.

In the step (a) it is possible to proceed to the next step without drying coffee grounds.

The coffee grounds from which biodiesel was extracted in step (a) can be classified according to the extraction method as follows: (1) organic solvent solvent (benzene, xylene, chloroform, hexane, ethyl acetate, methanol, ethanol, cyclohexane Coffee grounds, etc.); (2) coffee grounds through in-situ transesterification; (3) Coffee grounds extracted with steam and aqueous solutions of acid and base.

The aqueous solution of the activator is preferably 6 molar concentrations or less, preferably 0.5 to 6M in concentration. At the time of mixing, the mass ratio of the coffee ground material and the activator is preferably 1: 0.1 to 1: 3.

Since the purpose of step (a) is to secure porosity through chemical activity, the following activators may be used in addition to potassium hydroxide, but are not limited thereto: sodium hydroxide (NaOH), phosphoric acid (H ₃ PO ₄ ), and chlorides. Zinc (ZnCl ₂ ).

The mixing of the steps (a) and (c) may be both a mixing method through a stirrer and a mixing method through sonication, and the mixing time may vary depending on the amount of raw materials. Generally 30 minutes to 1 hour is suitable.

In addition to the method of mixing an activator such as potassium hydroxide in an aqueous solution state in the step (a), it is also possible to mix the activator with coffee grounds in powder form.

In the step (b), (c) or (d) it is preferable to dry at a temperature of 150 ℃ or less, preferably 50 ~ 150 ℃.

The gas of step (b) may be the use of inert gas, such as nitrogen, exhaust gas containing nitrogen, argon.

When the heat treatment in the step (d), the gas flow rate is 10 ~ 3000mLmin- ¹ is suitable, after increasing to 400 ~ 1000 ℃ at a temperature increase rate of 1 ~ 10 ℃ min ^-1 2 hours or less, preferably 1 After increasing the temperature to 400 ~ 1000 ℃ at a temperature increase rate of ~ 5 ℃ min ^-1 can be heat treated for a time of 0.5 to 2 hours.

The heat treatment of step (d) is a flow rate when converting carbon dioxide to carbon is 10 ~ 3000mLmin ^-1 and can be maintained for 0.5 to 2 hours at 500-1000 ℃ at a temperature increase rate of 1 ~ 5 ℃ min ^-1 .

In addition, in the heat treatment of step (d), when the carbon dioxide is not converted to carbon, the flow rate of the exhaust gas containing nitrogen, argon gas, or nitrogen is 10 to 3000 mlmin ^-1 , and the temperature is increased to 1 to 5 ° C min ^-1 . The speed can be maintained at 500 to 1000 ° C. for 0.5 to 2 hours.

Purification of (c) and (e) can be carried out by adding hydrochloric acid, water and ethanol. In particular, the purification of step (e) is to remove the salts remaining in the activated carbon after the heat treatment, at this time, hydrochloric acid, distilled water, ethanol can be used sequentially.

In addition to sodium borohydride, the boron precursor may use the following precursors: boron oxide (B ₂ O ₃ ), boric acid (H ₂ BO ₃ ), lithium boron hydride (LiBH ₄ ), potassium boron hydride (KBH ₄₎ ), Magnesium boron hydride (Mg (BH ₄ ) ₂ ), calcium boron hydride (Ca (BH ₄ ) ₂ ), strontium boron hydride (Sr (BH ₄ ) ₂ ) or ammonia borane (NH ₃ BH ₃ ) .

When preparing the boron precursor solution, a solvent may be an organic solvent such as dimethyl sulfoxide, dimethylformamide, and the like, and they do not react with sodium borohydride. The other boron precursors mentioned above can also be prepared using water, alcohols or organic solvents in a range that does not react.

The concentration of the boron precursor solution may vary depending on the solubility of the solvent. In general, the use of a solution of 0.5 to 6 molarity is preferred.

The present invention also includes a method for producing a high quality carbon material by adding a post-treatment step to the method for producing a carbon material described above. The step comprises the steps of: (i) mixing a boron precursor solution such as nitrogen-doped activated carbon with coffee grounds and sodium borohydride (NaBH ₄ ) solution; (ii) drying the mixed slurry; (iii) heat treating the dried slurry in a heating furnace through which carbon dioxide flows; (iv) purifying the resulting activated carbon with hydrochloric acid, water, ethanol and the like; (v) drying the activated carbon after purification; And (vi) completion of boron and nitrogen doped activated carbon.

In the step (i), both a mixing method through a stirrer and a mixing method through sonication may be possible, and the mixing time may vary depending on the amount of raw materials. Generally 30 minutes to 1 hour is suitable.

In addition to the method of mixing the boron precursor in an aqueous solution state in step (i), it is also possible to mix with activated carbon doped with nitrogen in the form of a powder.

The step (ii) is preferably dried at a temperature of less than 150 ℃, preferably 50 ~ 150 ℃.

Carbon dioxide conversion through the boron precursor in step (iii). In the process, boron is doped in the carbon structure of activated carbon. Therefore, the flow rate and heat treatment condition for carbon dioxide is important, the flow rate is 10 ~ 3000mLmin ^-1 is suitable. In the case of heat treatment, it is preferable to maintain the maximum 2 hours at 500-1000 degreeC by the temperature increase rate of 1-5 degreeCmin <^-1> .

In addition, if the carbon dioxide is not converted to carbon in the step (iii), other inert gas or exhaust gas containing nitrogen and nitrogen may be used. Flow rate and heat treatment conditions for this is important, the flow rate is 10 ~ 3000mLmin ^-1 is suitable. In the case of heat treatment, it is preferable to maintain the maximum 2 hours at 500-1000 degreeC by the temperature increase rate of 1-5 degreeCmin <^-1> .

The main purpose of step (iv) is to remove the salts remaining in the activated carbon after the heat treatment, in which case hydrochloric acid, distilled water and ethanol are used sequentially.

Step (v) is preferably dried at a temperature of less than 150 ℃, preferably 50 ~ 150 ℃.

The product obtained in step (vi) is activated carbon doped with boron and nitrogen, and the porous carbon material may be used as an electrode material of a secondary battery.

Therefore, in another aspect of the present invention relates to a heterogeneous element-doped carbon material of 1) nitrogen-doped porous carbon material and 2) boron and nitrogen co-doped porous carbon material prepared by the above method, and has a specific surface area of 500-3000m ² / is in the range of g.

The present invention also relates to an electrode material comprising 1) a nitrogen doped porous carbon material and / or 2) a boron and nitrogen co-doped porous carbon material.

The carbon material is suitable for use as an electrode material for supercapacitors or fuel cells. Further bromine oxidation / reduction can be utilized, so the active strip, in the Zn-Br redox flow cell as a material of the positive electrode _{^{(Br 2 + 2e - - ⇔}} 2Br).

In addition, it is possible to obtain a lipid or biodiesel as an additional product by the method for producing a heterogeneous carbon material using waste coffee of the present invention.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are only for illustrating the present invention, it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples.

EXAMPLE

Example  1: Nitrogen from various coffee grounds Doped  Preparation of Activated Carbon and Zinc-Bromium thereof Redox Flow Battery (Zinc-Bromine Redox  Flow Battery) Use as anode material

The overall manufacturing process follows the 'manufacturing of nitrogen-doped activated carbon' part of FIG. 1.

In the case of coffee grounds, activated carbon was prepared in two groups. The first group is general waste coffee grounds, and the second group is waste coffee grounds after extraction of lipids or biodiesel. Coffee grounds from which lipids or biodiesel are extracted are divided into three types according to the extraction method used: 1) coffee grounds extracted with chloroform; 2) coffee grounds that have undergone in-situ transesterification; 3) Coffee grounds extracted with steam. Therefore, activated carbon was prepared for all four types of coffee grounds without extracting the above oil components from the waste coffee grounds.

In one experiment, 2 g of dried coffee grounds were taken and mixed with aqueous potassium hydroxide solution. At this time, the concentration of the aqueous solution used was 6 mol concentration, and the amount was adjusted so that the mass ratio to coffee grounds is 1: 0.5. The sonication was performed for about 30 minutes so that the potassium hydroxide ions were evenly penetrated into the coffee grounds.

At the end of the sonication, the mixture took the form of a slurry, which was laid flat on the crucible (Fig. 2-1) and dried for one day only in a vacuum oven set at 100 ° C (Fig. 2-2).

The crucible containing the dried slurry was placed in an electric furnace, and purged for 30 minutes with flowing 50 mlmin ⁻¹ of nitrogen to remove oxidizing gas inside the electric furnace. Thereafter, the substrate was heated to 750 ° C. at a temperature rising rate of 5 ° C. min ⁻¹ , and then activated by heat treatment for 1 hour.

After the heat treatment, the activated carbon was dried in a vacuum oven set at 100 ° C. for one day after two hydrochloric acid treatments, two distilled water treatments, and one ethanol treatment. After drying, finally, the activated carbon doped with nitrogen was obtained (Fig. 2-3).

It was confirmed through BET analysis that the activated carbon produced through the present invention has a very high specific surface area value. Figure 3 shows the nitrogen adsorption isotherms (N ₂ adsorption isotherms) of each activated carbon, Figure 4 shows the distribution of micropores (micropore) affecting the electrochemical activity. Table 1 summarized the results.

Sample SBET
(m ² / g) Pore volume
(cm ³ / g) Micropore Mesopore Ratio One 21.89 0.0035 - - - 2 1501.68 0.60 0.57 (0.57) 0.02 28.5 3 2300.64 1.02 0.91 (0.90) 0.12 7.6

1: Comparative group without potassium hydroxide activation

2: activated carbon made from ordinary coffee grounds

3: Activated charcoal based on coffee grounds from biodiesel

This shows that activated carbon synthesized from coffee grounds has a high specific surface area and numerous micropores. This will serve as an advantageous part for the anode reaction of zinc-bromine redox flow battery.

The porous structure of activated carbon identified in the specific surface area analysis was also confirmed by scanning electron microscopy (SEM) (FIG. 5). Fig. 5A shows activated charcoal based on normal coffee grounds, and b shows activated carbon based on coffee grounds from which biodiesel is extracted.

Zinc-bromine LES anode reaction of the redox flow battery ^{_{(Br 2 + e - ⇔ 2Br}} -) to measure the electrochemical activity of the active was tested in a three electrode system of the (Quaternary ammonium bromide) QBr solution as an electrolyte. The activity of each activated carbon is shown in a graph of CV (Cyclic voltammetry) method (FIG. 6), a of FIG. 6 is activated carbon based on normal coffee grounds, and b is activated carbon based on coffee grounds extracted from biodiesel. , c is the result of the activated carbon of Example 2. Where area is proportional to activity. Thus, by changing the area according to the cycle for each activated carbon, the performance and durability were simultaneously shown (Fig. 7).

Example  2: nitrogen and boron Doped  Preparation of Activated Carbon and Zinc-Bromium thereof Redox Flow Battery (Zinc-Bromine Redox  Flow Battery) Use as anode material

Example 2 is a post-treatment process of Example 1 to obtain high quality activated carbon, and follows the part of 'Preparing Activated Carbon Doped with Boron and Nitrogen' of FIG. 1.

Example 2 was carried out on activated charcoal using general coffee grounds as the raw material of the activated carbon prepared in Example 1.

About 1 g of activated carbon was taken and mixed with 1 mol of sodium borohydride solution. At this time, the solvent used was dimethyl sulfoxide, so that the mass ratio to activated carbon was 1: 0.5. The sonication was performed for about 30 minutes so that the sodium borohydride ion was evenly infiltrated into the activated carbon.

The mixture in the form of a slurry was placed in a crucible and dried at 150 ° C. for only one day.

The crucible containing the dried slurry was placed in an electric furnace, and purged for 30 minutes with flowing 50 mlmin ⁻¹ of nitrogen to remove oxidizing gas inside the electric furnace. Then, after heating to 500 ℃ at a temperature increase rate of 5 ℃ min ^-1 was added to the carbon dioxide gas to cause the carbon dioxide conversion occurs. The flow rate at this time was 75 ml min ^-1 . And heat treatment for 2 hours.

After the heat treatment, the activated carbon was dried in a vacuum oven set at 100 ° C. for one day after two hydrochloric acid treatments, two distilled water treatments, and one ethanol treatment. After drying, finally, activated carbon doped with boron and nitrogen was obtained.

Doped with boron and nitrogen would be an advantageous part for the anode reaction of zinc-bromine redox flow cell. In order to determine this activity test was carried out in the same manner as in Example 1. CV graphs and graphs showing performance and durability were recorded (FIGS. 6 and 7).

It was confirmed from Examples 1 and 2 that activated carbon doped with nitrogen and activated carbon doped with nitrogen and boron were prepared from coffee grounds, which can be used as a zinc-bromine redox flow battery anode material. It was confirmed that.

As described above in detail the specific parts of the present invention, it is apparent to those skilled in the art that such specific description is merely a preferred embodiment, thereby not limiting the scope of the present invention. something to do. Thus, the substantial scope of the present invention will be defined by the appended claims and their equivalents.

Claims (19)

Method for producing hetero-doped carbon material using waste coffee comprising the following steps:
(a) mixing the waste coffee grounds with one or more 0.5 to 6 M aqueous solutions of activators selected from the group consisting of potassium hydroxide (KOH), sodium hydroxide (NaOH) and phosphoric acid (H ₃ PO ₄ ) to obtain a slurry ;
(b) drying the slurry of (a) and heat-treating the furnace in which an inert gas is introduced to obtain activated carbon; And
(c) purifying and drying the activated carbon of (b),
The mass ratio of the waste coffee grounds and the activator is 1: 0.1 ~ 1: 3,
The waste coffee grounds are extracted from the waste coffee grounds by using one or more organic solvents or steam selected from the group consisting of benzene, xylene, chloroform, hexane, ethyl acetate, methanol, ethanol, and cyclohexane, or a transfection reaction. Characterized in that the waste coffee waste generated after extracting the biodiesel through.
Method for producing hetero-doped carbon material using waste coffee comprising the following steps:
(a) mixing the waste coffee grounds with one or more 0.5-6 M aqueous activator solutions selected from the group consisting of potassium hydroxide (KOH), sodium hydroxide (NaOH) and phosphoric acid (H ₃ PO ₄ ) to obtain a slurry ;
(b) drying the slurry of (a) and heat-treating the furnace in which an inert gas is introduced to obtain activated carbon;
(c) purifying and drying the activated carbon of (b), and then adding and mixing the boron precursor to obtain a slurry;
(d) drying the slurry of (c) and heat-treating in a heating furnace into which gas is introduced to obtain activated carbon; And
(e) purifying the activated carbon of (d),
The mass ratio of the waste coffee grounds and the activator is 1: 0.1 ~ 1: 3,
The waste coffee grounds are one or more organic solvents or steam selected from the group consisting of benzene, xylene, chloroform, hexane, ethyl acetate, methanol, ethanol and cyclohexane in general waste coffee grounds or waste coffee grounds generated after coffee beverage production. Extracting lipids using or characterized in that the waste coffee waste generated after the extraction of biodiesel through a transfection reaction.
delete The method according to claim 1 or 2, wherein the waste coffee grounds of step (a) is dried at 50-150 ° C., followed by mixing an activator aqueous solution, and the drying of steps (b), (c) or (d) Method for producing a hetero-element carbon material using waste coffee, characterized in that carried out at a temperature of 50 ~ 150 ℃.
The method of claim 1 or 2, wherein the purification of step (c) is performed by adding hydrochloric acid, water and ethanol.
delete The method of claim 1 or 2, wherein the mixing of the steps (a) and (c) is carried out using a stirrer or sonication in the solid or slurry state of the hetero element doped carbon material using waste coffee Manufacturing method.
According to claim 1 or 2, wherein the heat treatment of step (b) is heated to 400 ~ 1000 ℃ at a rate of 1 ~ 10 ℃ min ^-1 under nitrogen or argon gas or nitrogen-containing exhaust gas 0.5 ~ 2 Method for producing a hetero-doped carbon material using waste coffee, characterized in that the heat treatment for a time period.
According to claim 2, wherein the heat treatment of step (d) is a flow rate when converting carbon dioxide to carbon is 10 ~ 3000mlmin ^-1 and 0.5 ~ 2 hours at 500-1000 ℃ at a temperature increase rate of 1 ~ 5 ℃ min ^-1 Method for producing a heterogeneous element-doped carbon material using waste coffee, characterized in that to maintain.
The method of claim 2, wherein the heat treatment of step (d) is a flow rate of nitrogen, argon or nitrogen containing exhaust gas when the carbon dioxide is not converted to carbon is 10 ~ 3000mlmin ^-1 , 1 ~ 5 ℃ min Method for producing a hetero-element doped carbon material using waste coffee, characterized in that for 0.5 to 2 hours at 500 ~ 1000 ℃ at a temperature rising rate of ^-1 .
The method of claim 2, wherein the boron precursor is sodium boron hydride (NaBH ₄ ), boron oxide (B ₂ O ₃ ), boric acid (H ₂ BO ₃ ), lithium boron hydride (LiBH ₄ ), potassium boron hydride (KBH ₄ ), magnesium boron hydride (Mg (BH ₄ ) ₂ ), calcium boron hydride (Ca (BH ₄ ) ₂ ), strontium boron hydride (Sr (BH ₄ ) ₂ ), and ammonia borane (NH ₃₎ BH ₃ ) A method for producing a hetero-element doped carbon material using waste coffee, characterized in that at least one selected from the group consisting of.
[Claim 3] The method for producing hetero-doped carbonaceous material according to claim 1 or 2, wherein lipid or biodiesel is obtained as a by-product.
delete delete Electrode material of zinc-bromine redox flow battery comprising a nitrogen-doped carbon material prepared by the method of claim 1.
Electrode material of zinc-bromine redox flow battery comprising a boron and nitrogen-doped carbon material prepared by the method of claim 2.
delete An electrode material of a zinc-bromine redox flow cell comprising a nitrogen doped carbon material prepared by the method of claim 1 and a boron and nitrogen doped carbon material prepared by the method of claim 2. delete

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