CN114291806A - Multi-scale regulation and control method for graphitization degree of low-order coal-based porous carbon - Google Patents
Multi-scale regulation and control method for graphitization degree of low-order coal-based porous carbon Download PDFInfo
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Abstract
The invention discloses a multi-scale regulation and control method for the graphitization degree of low-order coal-based porous carbon, which comprises the following steps: step one, pretreatment of low-rank coal; secondly, performing solid-phase mechanochemical treatment on the precursor raw material, an activating agent and the catalyst; step three, melting the mixture at low temperature; step four, activating the mixture at high temperature; and step five, post-treatment of the activated product. The method takes low-order weakly-sticky or non-sticky coal as a carbon source, and adopts a combined step of mechanochemistry and low-temperature melting to obtain a carbon source-potassium-based activator-boron-based graphitization degree catalyst solid-phase mixture which is deeply crosslinked and uniformly mixed; when the potassium-based activating agent etches and forms pores, the synergy of low-temperature catalytic graphitization mechanisms of potassium and boron is realized in the thermal conversion process of the low-order coal-carbon skeleton. The carbon material prepared by the method disclosed by the invention not only has developed pores, but also shows uniform development of a long-range graphitized structure, and shows excellent conductivity and rate capability when being used as a super-capacitor electrode material.
Description
Technical Field
The invention relates to a preparation method of a porous carbon material, and particularly relates to a multi-scale regulation and control method for the graphitization degree of low-order coal-based porous carbon.
Background
The super capacitor has the characteristics of rapid charge and discharge, long cycle life and the like, and is widely applied to high-power electrochemical energy storage scenes. The porous carbon material is the most important electrode active material in the super capacitor, and the regulation of the physical and chemical structure of the porous carbon material is the key for optimizing the energy density, the power density and the cycle life of the super capacitor. The high-performance porous carbon electrode material not only requires high specific surface area and pore volume to provide more active sites for ion storage, but also requires a long-range ordered carbon microcrystal structure to provide a channel for rapid conduction of electrons, and simultaneously ensures the cycling stability of the electrode material. However, carbon microcrystals in the traditional porous carbon material often have amorphous characteristics and low graphitization degree, so that the improvement of the power density of the carbon microcrystals serving as electrode materials of the super capacitor is limited, and the synergistic development of the porous carbon pore structure and the graphitization degree is an important direction for constructing the high-performance carbon-based super capacitor.
Heavy carbon feedstocks such as coal and its derivatives, biomass, etc., are structurally rich in large amounts of sp2The condensed aromatic ring with bonding property is an important raw material selection for preparing the porous carbon material. For example, coal and biomass have been used as examples, and many methods have been developed for producing porous carbon materials based on coal/biomass, mainly including physical activation and chemical activation, by pyrolysis in an active atmosphere (e.g., CO)2、H2O vapor) or activating agent (such as KOH) with carbon precursor to achieve etching pore-forming. However, the Carbon material directly prepared by physical or chemical activation method mainly has an amorphous Carbon structure, the structure contains a large amount of short-range microcrystalline fragments, and the graphitization degree is low [ Carbon 114 (2017) 98-105]Affecting its conductivity and long cycle stability as electrode material. In the aspect of improving the graphitization/graphene structure content in the porous carbon material, CN111710530A activates coal by using a K-based compound, and exerts the catalytic graphitization effect of metal K by improving the activation temperature, so that the graphitization degree of the material is improved to a certain extent. However, in the preparation process, only a simple liquid phase impregnation method is adopted for mixing, so that the mixing uniformity of the raw coal and the activating agent is poor, the chemical reagent cannot well penetrate into the carbon material, the regulation and control strength and the depth are insufficient, the material is still a graphitized carbon-amorphous carbon composite structure finally, and the long-range graphitized carbon structure has low content and poor uniformity.
In order to deeply improve the graphitization degree of the carbon material, the main approach adopted at present is catalytic graphitization. Document [ Energy& Fuels 26 8 (2012) 5186-5192]Selecting Taixi coal and Fe2(SO4)3The catalyst is used for increasing the graphitization degree of the Taixi coal to 91.98 ℃ at 2400 ℃, however, the high reaction temperature causes the prepared carbon material to lack pores, and the application of the carbon material in a super capacitor is limited. The low-temperature catalytic graphitization can be realized to a certain extent and the pores can be maintained by adding transition metal in the chemical activation pore-forming process, and the nitrate containing the transition metal is added as a graphitization degree catalyst while the gingko shell (biomass raw material) is activated by using alkali metal hydroxide by CN 102867654A; however, the introduction mode (liquid phase impregnation) of the transition metal ions still limits the depth, uniform formation and development of the graphitized structure in the subsequent activation process, and in addition, the transition metal ions (such as Cu) are added2+、Fe3+) Metal oxides are formed during the activation reaction and new metal impurities are introduced into the carbon structure.
The low-order weakly-sticky or non-sticky coal has rich reserves, a young carbon structure and high activity, and the deep regulation and control of the carbon structure are easy to realize in the thermal conversion process, so that the method is an important raw material selection for realizing the low-cost preparation of the porous carbon material; however, due to the lack of colloidal bodies and mobile phases in the structure, long-range ordered carbon microcrystals are difficult to develop in the thermal conversion process, and the problems of poor selection of an activating agent/a catalyst, uneven mixing of solid-phase substances, insufficient optimization of reaction conditions and the like exist in the conventional graphitized porous carbon preparation technology, so that the graphitization degree of a local area of the carbon material can be only improved, and the deep improvement and uniform development of the overall graphitization degree of the carbon material are difficult to realize.
Disclosure of Invention
Aiming at the problem that the pore and microcrystal structures are difficult to develop in a synergistic way in the porous carbon material prepared by the traditional method, the invention provides a multi-scale regulation and control method for the graphitization degree of low-order coal-based porous carbon. The method takes low-order weakly sticky or non-sticky coal with rich reserves, low cost and high carbon structure activity as a carbon source, and adopts the combined steps of mechanochemistry and low-temperature melting to obtain a carbon source-potassium-based activator-boron-based graphitization degree catalyst solid-phase mixture with deep crosslinking and uniform mixing; by optimizing the process conditions of the activation process, the synergy of the low-temperature catalytic graphitization mechanism of the potassium element and the boron element in the thermal conversion process of the low-order coal-carbon skeleton is realized while etching and pore-forming are carried out by the potassium-based activating agent. The carbon material prepared by the method disclosed by the invention not only has developed pores, but also shows uniform development of a long-range graphitized structure, and shows excellent conductivity and rate capability when being used as a super-capacitor electrode material.
The purpose of the invention is realized by the following technical scheme:
a multi-scale regulation and control method of low-order coal-based porous carbon graphitization degree is characterized in that low-order lignite/sub-bituminous coal or a pre-carbonization product thereof is used as a carbon source, and is subjected to solid-phase mechanochemical treatment with a potassium-based activating agent and a boron-based graphitization degree catalyst to realize solid-phase pre-crosslinking and uniform mixing; further carrying out low-temperature melting treatment on the solid phase mixture by utilizing the melting characteristic of a potassium-based activator to realize deep mixing of the activator, the catalyst and the carbon matrix in a smaller scale; and finally, realizing the synergistic development of the porous carbon pores and the graphitization degree within the range of 800-1100 ℃. As shown in fig. 1, the method comprises the following steps:
step one, pretreatment of low-rank coal: crushing, screening and drying low-rank coal to obtain refined coal powder serving as a precursor raw material, or further pre-carbonizing the refined coal powder serving as a precursor raw material, wherein:
the low-rank coal is weakly sticky or non-sticky coal and comprises lignite and subbituminous coal;
the grain size of the refined coal powder is 50 mu m-0.2 mm;
the pre-carbonization temperature is 500-800 ℃, and the time is 0.5-10 h;
step two, solid-phase mechanochemical treatment of the precursor raw material, the activating agent and the catalyst: carrying out solid-phase mechanochemical treatment on the precursor raw material, a potassium-based activating agent and a boron-based catalyst to pre-crosslink a solid-phase mixture and realize deep uniform mixing, wherein:
the potassium-based activator is KOH, and the boron-based graphitization degree catalyst is H3BO3；
The mechanochemical treatment atmosphere is air and CO2、N2Or Ar;
the mass ratio of the low-rank coal powder to the potassium-based activator to the boron-based catalyst is 1: 1-10: 0.5 to 5;
step three, low-temperature melting of the mixture: transferring the solid-phase mixture obtained in the step two to a nickel crucible, placing the nickel crucible in a tubular furnace, raising the temperature in the furnace to be higher than the melting temperature of the potassium-based substance (the temperature is not higher than the subsequent activation temperature) in an inert atmosphere, and keeping the temperature for a period of time to obtain a completely molten mixture, wherein:
the temperature of the low-temperature melting treatment is 300-600 ℃, and the time is 0.5-2 h;
the heating rate in the low-temperature melting process is 1-15 ℃/min;
the inert atmosphere is high-purity nitrogen or high-purity helium;
step four, high-temperature activation of the mixture: continuously heating the molten mixture formed in the third step under the inert atmosphere until the temperature reaches the reaction activation temperature, keeping the temperature for a period of time, and naturally cooling the temperature in the tubular furnace to room temperature to obtain an activated product, wherein:
the high-temperature activation temperature is 800-1100 ℃, and the activation constant-temperature time is 1-10 h;
the heating rate in the high-temperature activation process is 1-15 ℃/min;
the inert atmosphere is high-purity nitrogen or high-purity helium;
step five, post-treatment of the activated product: and (3) after acid washing and water washing are carried out on the product obtained in the fourth step, the product is placed in a drying oven to be dried, and the low-order coal-based graphitized porous carbon material with uniform and deep graphitization degree and capable of being applied to a super capacitor is obtained, wherein:
the pickling solution selected for post-treatment of the activated product is hydrochloric acid and hydrofluoric acid;
the concentration of the hydrochloric acid is 1-5 mol/L, and the mass fraction of the hydrofluoric acid is 1-10 wt%;
the drying temperature is 80 ℃, and the drying time is 24 hours;
the ash content of the low-rank coal-based graphitized porous carbon material is 0.05-0.2%;
the specific surface area of the low-rank coal-based graphitized porous carbon material is not less than 1800m2Degree of graphitization/gI G/I DThe value of the specific capacitance is not less than 2, the specific capacitance of the super capacitor electrode prepared by the material is more than 200F/g under low current density and the specific capacitance retention rate exceeds 55% under high current density of 50A/g under an aqueous three-electrode system.
Compared with the prior art, the invention has the following advantages:
(1) based on the combined steps of mechanochemistry and low-temperature melting, the deep crosslinking and uniform mixing of the carbon source-activator-catalyst are realized, and a foundation is laid for the uniform and deep development of the subsequent graphitized structure. The raw material mixing mode adopts solid-phase mechanochemical treatment to replace the traditional liquid-phase dipping or solid-phase mixing method, so that the low-rank coal, the potassium-based activating agent and the boron-based catalyst are subjected to solid-phase pre-crosslinking and are uniformly mixed; on the basis, the low-temperature melting characteristic of the potassium-based activator is further utilized, and under the promoting action of a liquid phase flow mechanism, the activator and the catalyst can better permeate into the carbon source structure, so that conditions are created for multi-scale promotion of the subsequent graphitization degree.
(2) Two low-temperature catalytic graphitization mechanisms occur simultaneously in the high-temperature activation pore-forming process, and the synergistic development of the pore structure and the graphitization degree is realized. When the pore is formed through high-temperature activation, boron in the boron-based catalyst has a high carburization characteristic, and the graphitization degree of the sheet layer is developed on a small-scale level by directly participating in the assembly of the carbon base surface/sheet layer; the potassium-based activator can generate a potassium simple substance existing in a steam form at high temperature, certain oxygen-containing functional groups on the surface of coal can be removed by potassium with strong reducibility to generate a large number of carbon dangling bonds, and meanwhile, the potassium can be intercalated in carbon lattices to weaken the van der Waals force between layers, so that a microchip layer is more easily peeled off, and then under the shuttle effect of the potassium, the carbon dangling bonds and the microchip layer are repaired, spliced and recombined on a large-scale layer. Under the synergistic effect of the two mechanisms, the multi-scale development and the deep promotion of the graphitization degree of the material are realized.
(3) The method solves the key bottleneck that the traditional porous carbon chemical or physical activation process is difficult to develop a long-range graphitized structure in a synergistic way in the pore-forming process. By changing the pretreatment mode of the low-rank coal, regulating the proportion of the coal powder and the activator/catalyst, preferably selecting the low-temperature melting temperature, the activation temperature and the activation time, the cooperation of multiple low-temperature graphitization mechanisms in the thermal conversion process of the carbon skeleton of the low-rank coal can be realized, so that the graphitization degree is greatly improved.
(4) The porous carbon prepared by the method has developed pores and high graphitization degree, and shows excellent conductivity and rate capability in super-capacitor energy storage. The specific surface area of the porous carbon prepared by the method can reach 2000m2More than g, even graphitized structure and graphitization degreeI G/I DA value of greater than 2, exhibits a distinct graphitization/graphene feature. Compared with commercial super-capacity carbon materials, the electric conductivity is improved by more than 5 times. As a supercapacitor electrode material, excellent specific capacity and capacity retention at high current density are exhibited.
(5) The method has the advantages that low-cost and large-reserve low-order weakly sticky or non-sticky coal is used as a carbon source, the traditional high-temperature graphitization treatment at the temperature of more than 2000 ℃ is not needed in the graphitization degree promotion process of the porous carbon, the reaction condition is mild, the operation steps are simple, and the potential of low-cost and macroscopic preparation is realized.
Drawings
FIG. 1 is a flow chart of the preparation of the porous graphitized carbon material of the present invention;
FIG. 2 is an SEM photograph of a carbon material (PGC-1) obtained in example 1, wherein (a) is an SEM photograph of PGC-1 at 10 μm and (b) is an SEM photograph of PGC-1 at 5 μm;
FIG. 3 is an SEM photograph of a carbon material (PGC-2) obtained in example 2, wherein (a) is an SEM photograph of PGC-2 at 10 μm and (b) is an SEM photograph of PGC-2 at 5 μm;
FIG. 4 is an SEM photograph of a carbon material (PC) obtained in comparative example 1, wherein (a) is an SEM photograph of PC at 10 μm and (b) is an SEM photograph of PC at 5 μm;
FIG. 5 is a graph showing the nitrogen adsorption isotherms of the carbon materials (PGC-1, PGC-2) obtained in examples 1 and 2 and the carbon material (PC) obtained in comparative example 1;
FIG. 6 is a Raman spectrum of the carbon materials (PGC-1, PGC-2) obtained in examples 1 and 2, wherein (1) and (2) are Raman spectra at typical spots of the sample under a microscope, and both show good graphitization degree;
FIG. 7 is a Raman spectrum of the carbon material (PC) obtained in comparative example 1, wherein (1) and (2) are Raman spectra at a typical spot of the sample under a microscope, and at (2) a larger spot, the graphitization degree of the sample is poor, and an amorphous carbon structure is present;
FIG. 8 is an X-ray diffraction pattern (XRD) of the carbon materials (PGC-1, PGC-2) obtained in examples 1 and 2 and the carbon material (PC) obtained in comparative example 1;
FIG. 9 is a graph showing the electric conductivities of the carbon materials (PGC-1, PGC-2) obtained in examples 1 and 2 and the carbon material (PC) obtained in comparative example 1;
FIG. 10 is a graph showing the cyclic voltammetry characteristics of a supercapacitor electrode made of the carbon material (PGC-1) obtained in example 1 in a 6M KOH electrolyte system;
FIG. 11 is a graph showing the charge and discharge characteristics of the supercapacitor electrode made of the carbon material (PGC-1) obtained in example 1 in a 6M KOH electrolyte system;
FIG. 12 is a current density-volume specific capacitance curve of a supercapacitor electrode made from the carbon material (PGC-1) obtained in example 1 in a 6M KOH electrolyte system;
FIG. 13 is a graph showing the cyclic voltammetry characteristics of the supercapacitor electrode made of the carbon material (PGC-2) obtained in example 2 in a 6M KOH electrolyte system;
FIG. 14 is a graph showing the charge/discharge characteristics of the supercapacitor electrode made of the carbon material (PGC-2) obtained in example 2 in a 6M KOH electrolyte system;
FIG. 15 is a current density-volume specific capacitance curve of a supercapacitor electrode made from the carbon material obtained in example 2 (PGC-2) in a 6M KOH electrolyte system.
Detailed Description
The technical solution of the present invention is further described below with reference to the accompanying drawings, but not limited thereto, and any modification or equivalent replacement of the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention shall be covered by the protection scope of the present invention.
Example 1
Transferring the low-rank raw coal (the east-west bituminous coal) which is ground, sieved and dried and has the particle size of 120-160 meshes into a quartz crucible, placing the quartz crucible into a tubular furnace, heating the quartz crucible to 700 ℃ from room temperature at the speed of 10 ℃/min under the nitrogen atmosphere (the flow is 200 mL/min), keeping the temperature for 1h, and taking out the coal sample which is obtained at the moment and is subjected to pre-carbonization treatment. Weighing 2g of the coal sample subjected to pre-carbonization treatment, and mixing the coal sample with the water according to a mass ratio of 1: 1: 4 in turn 2g H3BO3The powder and 8g of flake KOH were subjected to mechanochemical treatment to pre-crosslink and mix homogeneously. Transferring the solid-phase mixture to a nickel crucible, placing the nickel crucible in a pyrolysis tube furnace, introducing nitrogen (flow 200 mL/min), heating to 400 ℃ at the speed of 5 ℃/min, and keeping the temperature for 1h, wherein the mixture is molten; continuously heating the temperature of the tubular furnace from 400 ℃ to 1000 ℃, and keeping the temperature for 1h for high-temperature activation; after the tube furnace is naturally cooled to the room temperature, taking out the sample, washing the sample with 5mol/L dilute hydrochloric acid for 3 times, 6 hours each time, washing the sample with 10wt% hydrofluoric acid for 2 times, 6 hours each time, and carrying out deep acid washing on the sample; repeatedly centrifuging the pickled sample by using deionized water until the supernatant is neutral; and finally drying at 80 ℃ for 12h to obtain the low-order coal-based graphitized porous carbon material.
Mixing the carbon material with conductive carbon black and Polytetrafluoroethylene (PTFE) emulsion according to the weight ratio of 8: 1: 1, adding absolute ethyl alcohol, rolling to form a film, cutting to obtain a film with the mass of 1mg, adding anhydrous ethanol againRolling into 1cm size with water and ethanol2The electrode plate is covered with foam nickel and pressurized, and then is placed in a vacuum drying oven at 110 ℃ for 12 hours to prepare the electrode plate of the super capacitor. The electrochemical performance of the water system three-electrode system is tested by combining the water system three-electrode system with 6M KOH solution, a reference electrode of saturated calomel and a counter electrode of a Pt sheet.
The carbon material (PGC-1) obtained by using the low-order coal-based porous carbon graphitization degree multi-scale control method described in this embodiment: specific surface area of 1833m2(ii)/g; degree of graphitization of sample at light spot (1) under Raman test conditionsI G/I D2.69, degree of graphitization at spot (2)I G/I DIs 4.09; the resistivity of the material powder is tested, and the conductivity of the material under 10MPa is 24.42S cm-1(ii) a The specific capacitance of the super capacitor electrode made of the carbon material is 171.2F/g under low current density, the specific capacitance is still 95.6F/g under high current density (50A/g), the retention rate is 55.8%, and the super capacitor electrode has good rate capability.
Example 2
Weighing 2g of low-rank raw coal (Jundong subbituminous coal) with the particle size of 120-160 meshes after grinding, screening and drying, wherein the mass ratio of the raw coal to the subbituminous coal is 1: 1: 4 in turn 2g H3BO3The powder and 8g of flake KOH were subjected to mechanochemical treatment to pre-crosslink and mix homogeneously. Transferring the solid-phase mixture to a nickel crucible, placing the nickel crucible in a pyrolysis tube furnace, introducing nitrogen (flow 200 mL/min), heating to 400 ℃ at the speed of 5 ℃/min, and keeping the temperature for 1h, wherein the mixture is molten; continuously heating the temperature of the tubular furnace from 400 ℃ to 1000 ℃, and keeping the temperature for 1h for high-temperature activation; after the tube furnace is naturally cooled to the room temperature, taking out the sample, washing the sample with 5mol/L dilute hydrochloric acid for 3 times, 6 hours each time, washing the sample with 10wt% hydrofluoric acid for 2 times, 6 hours each time, and carrying out deep acid washing on the sample; repeatedly centrifuging the pickled sample by using deionized water until the supernatant is neutral; and finally drying at 80 ℃ for 12h to obtain the low-order coal-based graphitized porous carbon material.
Mixing the carbon material with conductive carbon black and Polytetrafluoroethylene (PTFE) emulsion according to the weight ratio of 8: 1: 1, and addingAdding anhydrous ethanol, rolling to form film, cutting to obtain 1mg film, adding anhydrous ethanol again, and rolling into 1cm area2The electrode plate is covered with foam nickel and pressurized, and then is placed in a vacuum drying oven at 110 ℃ for 12 hours to prepare the electrode plate of the super capacitor. The electrochemical performance of the water system three-electrode system is tested by combining the water system three-electrode system with 6M KOH solution, a reference electrode of saturated calomel and a counter electrode of a Pt sheet.
The carbon material (PGC-2) obtained by using the low-order coal-based porous carbon graphitization degree multi-scale control method described in this embodiment: the specific surface area is 2244m2(ii)/g; degree of graphitization of sample at light spot (1) under Raman test conditionsI G/I D3.11, degree of graphitization at spot (2)I G/I DIs 2.85; the resistivity of the material powder is tested, and the conductivity of the material under 10MPa is 15.33S cm-1(ii) a The specific capacitance of the super capacitor electrode made of the carbon material is 218.9F/g under low current density, the specific capacitance of the super capacitor electrode (50A/g) under high current density is still 116.6F/g, the retention rate is 53.2%, and the super capacitor electrode has good rate capability.
Example 3
This example differs from examples 1 and 2 in that the low rank coal is lignite.
Comparative example 1
2g of low-rank raw coal (Jundong sub-bituminous coal) with the particle size of 120-160 meshes after grinding, screening and drying is placed into a mortar according to the mass ratio of 1: 4, 8g of flaky KOH is added, and the mixture is fully and uniformly mixed after being ground. Transferring the mixture to a nickel crucible, placing the nickel crucible in a pyrolysis tube furnace, introducing nitrogen (flow 200 mL/min), heating to 1000 ℃ at the speed of 5 ℃/min, and activating for 1 h; after the tube furnace is naturally cooled to the room temperature, taking out the sample, washing the sample with 5mol/L dilute hydrochloric acid for 3 times, 6 hours each time, and then washing the sample with 10wt% hydrofluoric acid for 2 times, 6 hours each time; repeatedly centrifuging the pickled sample by using deionized water until the supernatant is neutral; and finally drying at 80 ℃ for 12h to obtain the porous carbon material.
Carbon material (PC) prepared using the method described in this comparative example: the specific surface area is 2342m2(ii)/g; sample under Raman test conditions in lightDegree of graphitization at spots (1)I G/I D6.37, degree of graphitization at spot (2)I G/I D1.07, the resistivity of the material powder was measured, and the conductivity of the material at 10MPa was 13.13S cm-1。
Claims (10)
1. A multi-scale regulation and control method for the graphitization degree of low-order coal-based porous carbon is characterized by comprising the following steps:
step one, pretreatment of low-rank coal: crushing, screening and drying low-rank coal to obtain refined coal powder serving as a precursor raw material;
step two, solid-phase mechanochemical treatment of the precursor raw material, the activating agent and the catalyst: carrying out solid-phase mechanochemical treatment on the precursor raw material, a potassium-based activating agent and a boron-based catalyst to pre-crosslink a solid-phase mixture and realize deep uniform mixing, wherein: the mass ratio of the low-rank coal powder to the potassium-based activator to the boron-based catalyst is 1: 1-10: 0.5 to 5;
step three, low-temperature melting of the mixture: transferring the solid-phase mixture in the step two to a nickel crucible, placing the nickel crucible in a tubular furnace, raising the temperature in the furnace to 300-600 ℃ under an inert atmosphere, carrying out low-temperature melting treatment, and keeping the temperature for 0.5-2 hours to obtain a completely molten mixture;
step four, high-temperature activation of the mixture: heating the molten mixture formed in the third step to 800-1100 ℃ under an inert atmosphere, carrying out high-temperature activation treatment, keeping the temperature constant for 1-10 h, and naturally cooling the temperature in the tubular furnace to room temperature to obtain an activated product;
step five, post-treatment of the activated product: and (4) pickling and washing the product obtained in the fourth step, and then placing the product in a drying oven for drying to obtain the low-order coal-based graphitized porous carbon material with uniform and deep graphitization degree.
2. The multi-scale regulation and control method for the graphitization degree of the low-rank coal-based porous carbon according to claim 1, characterized in that the low-rank coal is weakly sticky or non-sticky coal, and the particle size of the refined coal powder is 50 μm-0.2 mm.
3. The multi-scale regulating and controlling method for the graphitization degree of the low-rank coal-based porous carbon according to claim 1 or 2, wherein the low-rank coal is lignite or subbituminous coal.
4. The multi-scale regulation and control method for the graphitization degree of the low-order coal-based porous carbon according to claim 1 or 2, characterized in that the refined coal powder is further pre-carbonized to serve as a precursor raw material, the pre-carbonization temperature is 500-800 ℃, and the time is 0.5-10 h.
5. The multi-scale regulation and control method for graphitization degree of low-order coal-based porous carbon according to claim 1, characterized in that the potassium-based activator is KOH, and the boron-based graphitization degree catalyst is H3BO3。
6. The multi-scale regulation and control method for graphitization degree of low-order coal-based porous carbon according to claim 1, characterized in that the atmosphere of mechanochemical treatment is air and CO2、N2Or Ar.
7. The multi-scale regulation and control method for the graphitization degree of the low-order coal-based porous carbon according to claim 1, wherein the heating rate of low-temperature melting and high-temperature activation is 1-15 ℃/min.
8. The multi-scale regulating and controlling method for graphitization of low-order coal-based porous carbon according to claim 1, characterized in that the inert atmosphere for low-temperature melting and high-temperature activation is high-purity nitrogen or high-purity helium.
9. The multi-scale regulation and control method for the graphitization degree of the low-order coal-based porous carbon according to claim 1, wherein the pickling solution for pickling is hydrochloric acid and hydrofluoric acid, the concentration of the hydrochloric acid is 1-5 mol/L, and the mass fraction of the hydrofluoric acid is 1-10 wt%.
10. Use of the low-rank coal-based graphitized porous carbon material prepared by the method of any one of claims 1 to 9 in a supercapacitor.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103833028A (en) * | 2013-12-31 | 2014-06-04 | 深圳粤网节能技术服务有限公司 | Preparation method for graphene and graphene oxide based on anthracite |
| CN105314622A (en) * | 2015-11-13 | 2016-02-10 | 哈尔滨工程大学 | Method for preparing hetero-atom doped porous carbon material through carbonation of biomass under assistance of molten salt |
| CN105366658A (en) * | 2015-11-13 | 2016-03-02 | 哈尔滨工程大学 | Method for preparing porous carbon for super capacitor by waste plastic carbonization |
| CN110330016A (en) * | 2019-08-10 | 2019-10-15 | 哈尔滨工业大学 | An a kind of step cooperative development method of anthracite-base porous carbon graphite microcrystal and hole |
-
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- 2022-01-11 CN CN202210027150.6A patent/CN114291806B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103833028A (en) * | 2013-12-31 | 2014-06-04 | 深圳粤网节能技术服务有限公司 | Preparation method for graphene and graphene oxide based on anthracite |
| CN105314622A (en) * | 2015-11-13 | 2016-02-10 | 哈尔滨工程大学 | Method for preparing hetero-atom doped porous carbon material through carbonation of biomass under assistance of molten salt |
| CN105366658A (en) * | 2015-11-13 | 2016-03-02 | 哈尔滨工程大学 | Method for preparing porous carbon for super capacitor by waste plastic carbonization |
| CN110330016A (en) * | 2019-08-10 | 2019-10-15 | 哈尔滨工业大学 | An a kind of step cooperative development method of anthracite-base porous carbon graphite microcrystal and hole |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114890420A (en) * | 2022-04-22 | 2022-08-12 | 太原理工大学 | Preparation method of coal-based novel porous carbon electrode material |
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