CN113371709A - Preparation method of rice hull-based high-specific-surface-area biochar material - Google Patents
Preparation method of rice hull-based high-specific-surface-area biochar material Download PDFInfo
- Publication number
- CN113371709A CN113371709A CN202110822685.8A CN202110822685A CN113371709A CN 113371709 A CN113371709 A CN 113371709A CN 202110822685 A CN202110822685 A CN 202110822685A CN 113371709 A CN113371709 A CN 113371709A
- Authority
- CN
- China
- Prior art keywords
- biochar
- rice hull
- specific
- preparation
- area
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/30—Active carbon
- C01B32/312—Preparation
- C01B32/318—Preparation characterised by the starting materials
- C01B32/324—Preparation characterised by the starting materials from waste materials, e.g. tyres or spent sulfite pulp liquor
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/30—Active carbon
- C01B32/312—Preparation
- C01B32/342—Preparation characterised by non-gaseous activating agents
- C01B32/348—Metallic compounds
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/30—Active carbon
- C01B32/354—After-treatment
- C01B32/36—Reactivation or regeneration
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Materials Engineering (AREA)
- Carbon And Carbon Compounds (AREA)
- Battery Electrode And Active Subsutance (AREA)
Abstract
The invention discloses a preparation method of a rice hull-based high-specific-surface-area biochar material, which comprises the following steps: s1, crushing, namely crushing and sieving rice hulls to obtain rice hull powder, and then pickling; s2, carbonizing, namely putting the acid-washed rice hulls into a muffle furnace to be heated, wherein the final temperature is 600-; s3, dissolving silicon, mixing the rice hull-based biochar with a KOH solution, and carrying out primary reaction at 20 ℃; s4, activating, namely mixing the preliminary silicon-dissolved biochar with KOH powder, grinding, putting into a muffle furnace, and preserving heat in a nitrogen atmosphere at 900 ℃; s5, drying, mixing the obtained activated carbon with deionized water, putting the mixture into a magnetic stirrer, stirring for 4-5h, filtering, and drying to obtain the biochar. The preparation method of the rice hull-based high-specific-surface-area biochar material can solve the problems of small specific surface area and irregular pore size distribution of biochar prepared by the existing activated carbon preparation method.
Description
Technical Field
The invention relates to the technical field of preparation of activated carbon materials, in particular to a preparation method of a rice hull-based high-specific-surface-area biochar material.
Background
The activated carbon is a graphite microcrystalline carbon material which is composed of elements such as carbon, hydrogen, oxygen, nitrogen, sulfur and the like and has high specific surface area, porous structure and strong adsorption capacity. The traditional activated carbon material is a non-metal material obtained by processing and treating coal, petroleum or processed products of the coal, the petroleum or the processed products of the coal and the petroleum. With the proposal of '3060 carbon neutralization and carbon peak-reaching', people gradually realize that the utilization of biomass waste resources plays an important role in alleviating greenhouse effect and air pollution, so that the biomass waste is recycled to prepare high-performance activated carbon, the high-performance activated carbon has high environmental protection value, and the outstanding problem of environmental pollution caused by random abandonment or incineration of agricultural waste is solved.
With the wider application of the activated carbon in various fields, higher requirements are put on the specific surface area of the activated carbon, and the specific surface area exceeds 2000m2The active carbon per kg shows good electrochemical performance in the fields of super capacitors and the like. The current method for preparing the biochar mainly comprises two stages of carbonization and activation. The carbonization stage is to remove most impurities except the carbon material by pyrolyzing the raw material at high or low temperature, most of which is left to be carbonaceous and generate a large number of micropores. The activation stage refers to a process of activating the functional groups by physical or chemical methods to change the micropore distribution of the functional groups, and generating some new functional groups. However, the specific surface area of the biochar activated by the existing method is only 500-1700m2/kg, and the pore size distribution is irregular, mainly microporous, resulting in poor adsorption performance.
Disclosure of Invention
The invention aims to provide a preparation method of a rice hull-based high-specific-surface-area biochar material, which solves the problems of small specific surface area and irregular pore size distribution of biochar prepared by the existing preparation method of activated carbon.
In order to realize the aim, the invention provides a preparation method of a rice hull-based high-specific-surface-area biochar material, which comprises the following steps:
s1, crushing, namely crushing and sieving the rice hulls to obtain rice hull powder, and then acid-washing to obtain acid-washed rice hulls;
s2, carbonizing, namely putting the acid-washed rice hulls into a muffle furnace for heating, carbonizing in the atmosphere of nitrogen, wherein the heating rate is 20-25 ℃/min, the final temperature is 600-;
s3, dissolving silicon, mixing the rice hull-based biochar with a KOH solution, carrying out preliminary reaction at 20 ℃, carrying out suction filtration to collect solids, fully carrying out suction filtration and washing by using deionized water, and drying in a drying oven to obtain preliminary silicon-dissolved biochar;
s4, activating, namely mixing the preliminary silicon-dissolved biochar with KOH powder, grinding, putting into a muffle furnace, and preserving heat in a nitrogen atmosphere at 900 ℃ to obtain activated carbon;
s5, drying, mixing the obtained activated carbon with deionized water, putting the mixture into a magnetic stirrer to stir for 4-5h, performing suction filtration to collect solids, performing suction filtration washing by using the deionized water, and putting the mixture into a drying box to dry for 12h to obtain the biochar.
Preferably, in the step S1, the grain size of the rice hull powder is 150-250 μm.
Preferably, in step S2, the holding time after the final temperature is reached is 30 min.
Preferably, in the step S3, the concentration of the KOH solution is 5 wt%, and the solid-to-liquid ratio of the rice hull-based biochar to the KOH solution is 1: 10.
Preferably, in the step S3, the time of the preliminary reaction is 2-2.5 h.
Preferably, in the step S3, the temperature of the drying oven is 100-110 ℃, and the drying time is 11-13 h.
Preferably, in the step S4, the mass ratio of the preliminary silicon-dissolving biochar to the KOH powder is 1:4, the temperature rise rate of the muffle furnace is 20-25 ℃/min, and the temperature is maintained for 30 min.
The rice hull-based biochar with high specific surface area is adoptedThe specific surface area of the biochar prepared by the preparation method of the material reaches 3424.4m2(g) the mesoporous area is 1563.03m2/g。
The preparation method of the rice hull-based high-specific-surface-area biochar material has the advantages and positive effects that:
1. the rice hulls are crushed and then are pickled, so that impurities of the rice hulls can be effectively removed, and inorganic salts and heavy metal compounds in the rice hulls are dissolved, and carbonization of the rice hulls is facilitated.
2. Using KOH solution to dissolve silicon, K in the silicon dissolving process2SiO3The formation process is easy to pass through SiO contained in the rice hull-based biochar2Opening the inner pore channel of the biochar to obtain the high-quality graded pore channel silicon-dissolved biochar.
3. Activating with KOH powder under nitrogen atmosphere, and using CO generated during heating2/H2O/NH3Synthesizing and doping functional groups on the surface of the silicon-dissolving biochar, realizing the orderly construction of multi-scale structural functional elements of the silicon-dissolving biochar functional groups (atomic scale) -pores (nano/sub-nano scale) -carbon skeleton (micro-nano scale), and obtaining the biochar with larger specific surface area.
The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.
Drawings
FIG. 1 is a distribution diagram of the pore size of biochar in an embodiment of a preparation method of a rice hull-based high-specific-surface-area biochar material of the invention;
FIG. 2 is an SEM image of biochar in an embodiment of the preparation method of the rice hull-based high-specific-surface-area biochar material;
FIG. 3 is a two-electrode constant current charge and discharge curve diagram of an embodiment of the preparation method of the rice hull-based high specific surface area biochar material of the invention;
FIG. 4 is a mass specific capacitance comparison diagram under different current densities in a three-electrode system according to an embodiment of a method for preparing a rice hull-based high specific surface area biochar material of the present invention;
fig. 5 is a cyclic voltammetry characteristic curve diagram of an embodiment of a preparation method of a rice hull-based high-specific-surface-area biochar material.
Detailed Description
The technical solution of the present invention is further illustrated by the accompanying drawings and examples.
Examples
A preparation method of a rice hull-based high-specific-surface-area biochar material comprises the following steps:
s1, crushing and sieving the rice hulls to obtain rice hull powder, and then acid washing to obtain acid-washed rice hulls. The grain size of the rice hull powder is 150-250 mu m. The crushed rice hulls are pickled, impurities in the rice hulls can be removed through pickling, inorganic salts and heavy metal compounds in the rice hulls are dissolved, and the heavy metal content is effectively reduced.
S2, carbonizing, namely putting the acid-washed rice hulls into a muffle furnace for heating, carbonizing in the atmosphere of nitrogen, wherein the heating rate is 20-25 ℃/min, the final temperature is 600-700 ℃, and the heat preservation time is 30min after the final temperature is reached, so that the rice hull-based biochar is obtained. The rice hulls after the acid washing are carbonized at the temperature of 600-700 ℃, so that volatile non-carbon components in the rice hulls can be effectively removed, lignocellulose contained in the rice hulls is decomposed, and the cellular cavities of the rice hulls form a microporous loose structure. The rice hull-based biochar comprises carbon and silicon as basic components and SiO in rice hulls2In the carbonization process, SiO in the confined space occurs under the protection of carbon2Growth of particles, removal of AAEM elements during carbonization, in SiO2A medium/large pore space is created within the confined space.
S3, dissolving silicon, namely mixing the rice hull-based biochar with a KOH solution, wherein the concentration of the KOH solution is 5 wt%, and the solid-to-liquid ratio of the rice hull-based biochar to the KOH solution is 1: 10. The primary reaction is carried out at the temperature of 20 ℃, and the time of the primary reaction is 2-2.5 h. And (4) carrying out suction filtration to collect solids, fully carrying out suction filtration washing by using deionized water, and drying in a drying oven to obtain the preliminary silicon-dissolved biochar. The temperature of the drying box is 100-110 ℃, and the drying time is 12 h.
KOH reacts with silicon dioxide in the rice hull-based biochar to obtain K2SiO3Thereby dissolving the silicon contained in the rice hulls. K2SiO3The formation process is easy to pass through SiO contained in the rice hull-based biochar2Opening the inner pore passage of the biochar to obtain the high-quality macroporous-mesoporous-microporous graded three-dimensional silicon-dissolved biochar penetrating the step pore passage.
And S4, activating, namely mixing the preliminary silicon-dissolved biochar with KOH powder, grinding, putting into a muffle furnace, and preserving heat under the nitrogen atmosphere at 900 ℃ to obtain activated carbon. The mass ratio of the preliminary silicon-dissolving biochar to the KOH powder is 1:4, the heating rate of the muffle furnace is 20-25 ℃/min, and the temperature is kept for 30 min.
Activating silicon-dissolving biochar by KOH powder in the atmosphere of nitrogen, and utilizing CO generated in the heating process2/H2O/NH3Synthesizing and doping functional groups on the surface of the silicon-dissolving biochar to realize the orderly construction of multi-scale structural functional elements of the silicon-dissolving biochar functional groups (atomic scale) -pores (nano/sub-nano scale) -carbon skeleton (micro-nano scale).
S5, drying, mixing the obtained activated carbon with deionized water, putting the mixture into a magnetic stirrer to stir for 4-5h, performing suction filtration to collect solids, performing suction filtration washing by using the deionized water, and putting the mixture into a drying box to dry for 12h to obtain the biochar.
The biochar prepared by the preparation method of the rice hull-based high-specific-surface-area biochar material is characterized in that:
according to the description in the table, the specific surface area of the biochar prepared by the preparation method reaches 3424.4m2(g) the mesoporous area is 1563.03m2/g。
According to the results shown in fig. 1 and fig. 2, the biochar prepared by the preparation method of the invention has uniform pore size distribution and large specific surface area, and is beneficial to improving the adsorption performance of activated carbon.
According to the experimental result of fig. 3, the charging and discharging curve of the supercapacitor assembled by the biochar prepared by the preparation method of the invention is triangular, which shows that the supercapacitor has double electric layer energy storage. In fig. 4, the capacitance is slightly decreased with an increase in current density in the three electrodes, which shows that the rate performance is good. In fig. 5, the cyclic voltammetry curves are similar in shape to rectangles, which indicate that the electric double layer energy storage is mainly achieved, no significant redox peaks are present, and the pseudocapacitance is low or absent; the symmetry is good, which indicates that the capacitance reversibility is strong.
Therefore, the method for preparing the rice hull-based high-specific-surface-area biochar material can solve the problems of small specific surface area and irregular pore size distribution of biochar prepared by the existing activated carbon preparation method. The prepared charcoal has the advantages of good multiplying power and strong reversibility when applied to the capacitor.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the invention without departing from the spirit and scope of the invention.
Claims (8)
1. A preparation method of a rice hull-based high-specific-surface-area biochar material is characterized by comprising the following steps: the method comprises the following steps:
s1, crushing, namely crushing and sieving the rice hulls to obtain rice hull powder, and then acid-washing to obtain acid-washed rice hulls;
s2, carbonizing, namely putting the acid-washed rice hulls into a muffle furnace for heating, carbonizing in the atmosphere of nitrogen, wherein the heating rate is 20-25 ℃/min, the final temperature is 600-;
s3, dissolving silicon, mixing the rice hull-based biochar with a KOH solution, carrying out preliminary reaction at 20 ℃, carrying out suction filtration to collect solids, fully carrying out suction filtration and washing by using deionized water, and drying in a drying oven to obtain preliminary silicon-dissolved biochar;
s4, activating, namely mixing the preliminary silicon-dissolved biochar with KOH powder, grinding, putting into a muffle furnace, and preserving heat in a nitrogen atmosphere at 900 ℃ to obtain activated carbon;
s5, drying, mixing the obtained activated carbon with deionized water, putting the mixture into a magnetic stirrer to stir for 4-5h, performing suction filtration to collect solids, performing suction filtration washing by using the deionized water, and putting the mixture into a drying box to dry for 12h to obtain the biochar.
2. The preparation method of the rice hull-based high-specific-surface-area biochar material according to claim 1 is characterized in that: in the step S1, the grain size of the rice hull powder is 150-250 μm.
3. The preparation method of the rice hull-based high-specific-surface-area biochar material according to claim 1 is characterized in that: in step S2, the holding time is 30min after the final temperature is reached.
4. The preparation method of the rice hull-based high-specific-surface-area biochar material according to claim 1 is characterized in that: in the step S3, the concentration of the KOH solution is 5 wt%, and the solid-to-liquid ratio of the rice hull-based biochar to the KOH solution is 1: 10.
5. The preparation method of the rice hull-based high-specific-surface-area biochar material according to claim 1 is characterized in that: in the step S3, the time of the primary reaction is 2-2.5 h.
6. The preparation method of the rice hull-based high-specific-surface-area biochar material according to claim 1 is characterized in that: in the step S3, the temperature of the drying oven is 100-110 ℃, and the drying time is 11-13 h.
7. The preparation method of the rice hull-based high-specific-surface-area biochar material according to claim 1 is characterized in that: in the step S4, the mass ratio of the preliminary silicon-dissolving biochar to the KOH powder is 1:4, the temperature rise rate of the muffle furnace is 20-25 ℃/min, and the temperature is kept for 30 min.
8. MiningThe specific surface area of the biochar prepared by the method for preparing the rice hull-based high-specific-surface-area biochar material according to any one of claims 1 to 7 reaches 3424.4m2(g) the mesoporous area is 1563.03m2/g。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110822685.8A CN113371709A (en) | 2021-07-21 | 2021-07-21 | Preparation method of rice hull-based high-specific-surface-area biochar material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110822685.8A CN113371709A (en) | 2021-07-21 | 2021-07-21 | Preparation method of rice hull-based high-specific-surface-area biochar material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113371709A true CN113371709A (en) | 2021-09-10 |
Family
ID=77582530
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110822685.8A Pending CN113371709A (en) | 2021-07-21 | 2021-07-21 | Preparation method of rice hull-based high-specific-surface-area biochar material |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113371709A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114572980A (en) * | 2022-03-21 | 2022-06-03 | 山东大学 | Porous activated carbon material and preparation method and application thereof |
| CN114950366A (en) * | 2022-06-27 | 2022-08-30 | 吉林农业大学 | Preparation and application of samara biomass charcoal |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20020007458A (en) * | 2000-07-13 | 2002-01-29 | 김명수 | Preparing method of rice hull activated carbon for electric double layer capacitor |
| CN104150461A (en) * | 2014-07-17 | 2014-11-19 | 吉林大学 | Environment-friendly preparation method for rice-hull-based capacitor carbon material with hierarchical porous structure |
| CN109704338A (en) * | 2019-02-20 | 2019-05-03 | 吉林大学 | A kind of method of modifying of rice husk base capacitor Carbon Materials |
| CN113060738A (en) * | 2021-03-22 | 2021-07-02 | 哈尔滨工业大学 | Preparation of rice hull source functional carbon based on novel ammonia method carbon capture and nano SiO2Synthesis method |
-
2021
- 2021-07-21 CN CN202110822685.8A patent/CN113371709A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20020007458A (en) * | 2000-07-13 | 2002-01-29 | 김명수 | Preparing method of rice hull activated carbon for electric double layer capacitor |
| CN104150461A (en) * | 2014-07-17 | 2014-11-19 | 吉林大学 | Environment-friendly preparation method for rice-hull-based capacitor carbon material with hierarchical porous structure |
| CN109704338A (en) * | 2019-02-20 | 2019-05-03 | 吉林大学 | A kind of method of modifying of rice husk base capacitor Carbon Materials |
| CN113060738A (en) * | 2021-03-22 | 2021-07-02 | 哈尔滨工业大学 | Preparation of rice hull source functional carbon based on novel ammonia method carbon capture and nano SiO2Synthesis method |
Non-Patent Citations (3)
| Title |
|---|
| XIAO, Y 等: "Hierarchical Porous Carbons Derived from Rice Husk for Supercapacitors with High Activity and High Capacitance Retention Capability", 《CHEMISTRYSELECT》 * |
| YONG XIAO ET AL: "Hierarchical Porous Carbons Derived from Rice Husk for Supercapacitors with High Activity and High Capacitance Retention Capability", 《CHEMISTRYSELECT》 * |
| 刘德臣: "多级孔道结构的稻壳基电容炭材料的制备及其电容性能研究", 《中国优秀博硕士学位论文全文数据库（博士）工程科技I辑》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114572980A (en) * | 2022-03-21 | 2022-06-03 | 山东大学 | Porous activated carbon material and preparation method and application thereof |
| CN114950366A (en) * | 2022-06-27 | 2022-08-30 | 吉林农业大学 | Preparation and application of samara biomass charcoal |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108529587B (en) | Preparation method and application of phosphorus-doped biomass graded porous carbon material | |
| JP5400892B2 (en) | Method for producing porous activated carbon | |
| CN109081342B (en) | Date palm leaf biomass porous activated carbon and preparation method and application thereof | |
| CN109796003B (en) | Coal-based hard carbon surface oxygen functional group directional regulation and control method for sodium storage cathode | |
| CN113666356B (en) | Shell biomass-based hard carbon negative electrode material of sodium ion battery and preparation method | |
| CN111115629A (en) | High-specific-surface-area carbon material based on waste tobacco stems and preparation method and application thereof | |
| CN107089659B (en) | Radio frequency plasma is modifies quickly to prepare enzymolysis xylogen base richness nitrogen active carbon method | |
| CN107151014B (en) | Biological porous carbon-based lithium-sulfur battery positive electrode material and preparation method thereof | |
| CN113371709A (en) | Preparation method of rice hull-based high-specific-surface-area biochar material | |
| CN113135568A (en) | Nitrogen-doped porous carbon material and preparation method and application thereof | |
| CN115159522B (en) | Biomass nitrogen-sulfur or nitrogen-phosphorus double-doped activated carbon material for battery negative electrode material and preparation method thereof | |
| CN112645305A (en) | Preparation method of pre-activated pore-forming and high-temperature carbonization combined anthracite-based hard carbon material | |
| CN107910200A (en) | A kind of preparation method of multi-stage porous nitrogen oxygen doping carbon supercapacitor electrode material | |
| CN115124025A (en) | Hard carbon material, preparation method thereof and application thereof in sodium-ion battery | |
| CN108358203B (en) | Preparation method of biomass porous graphene structure activated carbon | |
| CN114394592B (en) | Method for modulating sludge-based hierarchical porous phosphorus-containing carbon by microwaves for super capacitor | |
| CN112299390B (en) | Three-dimensional frame structure grading porous biochar and preparation method thereof | |
| CN108314037A (en) | A kind of porous carbon materials and the preparation method and application thereof with cell cytoskeleton structure | |
| CN114188511B (en) | Nitrogen-doped carbon-coated graphite composite material and preparation method and application thereof | |
| CN111333068A (en) | Preparation method and application of biomass porous carbon material based on nut shells | |
| CN111977651A (en) | Preparation method of potassium carbonate chemically activated low-order carbon source based porous carbon | |
| CN115092905A (en) | Amorphous carbon material modified by carbon points and preparation method and application thereof | |
| CN113716562A (en) | Method for preparing porous carbon material by treating tobacco waste with molten salt | |
| CN112635202A (en) | Nickel cobaltate @ graphene @ China fir composite material electrode and preparation method and application thereof | |
| CN112174119B (en) | Method for preparing graphene foam from antibiotic fungi residues |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210910 |