CN110015661A - A method of nitrogen-dopped activated carbon is prepared using discarded cigarette butt - Google Patents
A method of nitrogen-dopped activated carbon is prepared using discarded cigarette butt Download PDFInfo
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- CN110015661A CN110015661A CN201910295746.2A CN201910295746A CN110015661A CN 110015661 A CN110015661 A CN 110015661A CN 201910295746 A CN201910295746 A CN 201910295746A CN 110015661 A CN110015661 A CN 110015661A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y40/00—Manufacture or treatment of nanostructures
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- 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
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- 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
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Abstract
The invention belongs to porous carbon materials preparation technical field, specially a kind of method for preparing nitrogen-dopped activated carbon using discarded cigarette butt.The method of the present invention obtains nitrogen-dopped activated carbon by carbonization, alkali leaching, carbonization, pickling, drying and processing using discarded cigarette butt as raw material.Activated carbon surface product range obtained is 1355 ~ 2455 m2/ g, average pore size are distributed as 1.9 ~ 2.2 nm, and nitrogen content is 0.2 ~ 0.7%, are with a wide range of applications in the fields such as gas absorption and supercapacitor.Preparation method of the present invention is simple, replaces timber to prepare active carbon using discarded cigarette butt, the use of nontoxic compound is activator, has important practical significance to the recycling and environmental protection of waste resource.
Description
Technical field
The invention belongs to porous carbon materials preparation technical fields, and in particular to prepare nitrogen-dopped activated carbon using discarded cigarette butt
Method.
Background technique
Because of its big specific surface area and high chemical stability, active carbon is being adsorbed, and the fields such as catalysis and the energy obtain extensively
General application.Currently, the preparation of active carbon mainly uses log scale and coal etc..Not only price is higher for these raw material, but also mistake
The exploitation of degree is also larger to environmental hazard.In contrast, biomass and life or trade waste etc. are not only cheap, but also
With the very high value of environmental protection.Therefore, increasing as the research of activated carbon raw material using biomass or waste[1-3]。
The absorption property of active carbon mostlys come from the physisorption of its abundant micropore.Equally, it is applied to super
When the energy class material such as capacitor, the energy-storage property of active carbon is acted on from the electric double layer capacitance of micropore.If it is intended into one
Step improves absorption and the energy-storage property of active carbon, needs to optimize the chemical constituent of active carbon.Studies have shown that N doping on the one hand can
Absorption property is improved to generate chemisorption, redox reaction on the other hand can also be participated in and improve energy-storage property.Cause
This, the N doping of active carbon is increasingly interested by researchers.
Currently, the main method for preparing nitrogen-dopped activated carbon be will carbon source, nitrogen source and activator mix after calcine, such as:
A kind of preparation method and applications (patent No. 201610564590.X) of N doping starch base activated carbon microballon material, it
Including gelatinization and hydro-thermal after mixing starch with nitrogenous compound, high-temperature activation is obtained after then mixing hydro-thermal coke with activating agent
To the activated carbon microballon of N doping.Obtained active carbon specific surface area is 1000 ~ 3300 m2/ g, nitrogen content are 0.2 ~ 16%,
Average pore size is 2 ~ 4nm.This method step is complicated, to experimenter and equipment all have it is higher must ask, the prices of raw materials compared with
It is high.In addition, the raw material of solid mixing are uneven, it is lower for the utilization rate of activator and carbon source.
A kind of nitrogen-dopped activated carbon catalyst and its (patent No. 201410854518.1) is applied, it includes soaking active carbon
Then the active carbon of leaching lag is calcined in nitrogen atmosphere high temperature, obtains N doping by the stagnant hydrating solution in nitrogenous compound
Active carbon.This method is needed using a large amount of nitrogen sources, and conversion ratio is lower.
So far, there has been no using discarded cigarette butt as raw material, nitrogen-dopped activated carbon is prepared as activator using carbonate and is had leisure
Open technology.This method also has the advantage that (1) discards cigarette butt and has certain nitrogen content, does not need using additional nitrogen source i.e.
The active carbon that N doping can be obtained, has effectively saved cost；(2) use nontoxic carbonate and bicarbonate as work
Agent, compared to traditional hydroxide with for safely and effectively；(3) simple process, activation temperature is lower, has saved electric energy；(4)
Active carbon is prepared using discarded cigarette butt as raw material, has not only widened the raw material sources of high-performance nitrogen-dopped activated carbon, but also realize
The recycling and reusing of waste resource has positive environment protection significance.
Summary of the invention
The object of the present invention is to provide a kind of cheap, convenient methods for preparing nitrogen-dopped activated carbon using discarded cigarette butt.
The method provided by the invention for preparing nitrogen-dopped activated carbon using discarded cigarette butt is passed through using discarded cigarette butt as raw material
Carbonization, alkali leaching, carbonization, pickling, drying and processing obtain nitrogen-dopped activated carbon；Specific steps are as follows:
(1) collect discarded cigarette butt raw material washed, drying and processing, then in nitrogen atmosphere, 330 ~ 370 DEG C carbonization 1 ~ 2
Hour；
(2) by the carbonization abrasive lapping in step (1), mixed with alkali inorganic substance aqueous solution by certain mass ratio, at 75-85 DEG C
It is dried in air dry oven；It is preferred that being dried at 80 DEG C；Wherein:
The alkali inorganic substance is sodium carbonate, sodium bicarbonate, potassium carbonate and saleratus it is one or more；
The carbonized stock and the quality of alkali inorganic substance are 0.5 ~ 4.0 than range；It is preferred that the two quality is 1 ~ 3.0 than range；
(3) material handled through step (2) is put into tube furnace, under nitrogen protection, 600 ~ 800 DEG C are carbonized and activate 1 ~ 2
Hour；
(4) material handled through step (3) is washed 12 ~ 24 hours with 1 ~ 3mol/L dilute hydrochloric acid solution under magnetic stirring, most
After be washed with deionized to filtrate pH=6 ~ 7, filtering, at 75-85 DEG C in air dry oven drying to get N doping is arrived
Active carbon.It is preferred that being dried at 80 DEG C.
The active carbon of N doping prepared by the present invention, surface area are 1355 ~ 2455 m2/ g, average pore size point
Cloth is 1.9 ~ 2.2 nm, and nitrogen content is 0.2 ~ 0.7%, is had in fields such as electrochemical energy storage, adsorbing separation, catalyst carriers wide
Wealthy application prospect.
The beneficial effects of the present invention are:
(1) it discards the burning of cigarette butt and buries not only to form environment and pollute, but also cause the waste of resource.The present invention is directed to
Such case proposes a kind of method for preparing nitrogen-dopped activated carbon with discarded cigarette butt, turns waste into wealth, and provides a kind of waste again
The approach utilized；
(2) need to improve the cost of material, this hair in the preparation of most of nitrogen-dopped activated carbon using additional nitrogen source at present
It is bright to use discarded cigarette butt that there is certain nitrogen content, addition nitrogenous material is not needed, cost has been saved；
(3) activator that active carbon preparation at present uses is mostly hydroxide, such as sodium hydroxide and potassium hydroxide.These are lived
Agent is not only expensive, but also has stronger corrosivity, is easy to cause damages to user.The present invention uses nontoxic carbon
Hydrochlorate and bicarbonate, not only lower cost, but also reduce harm of the preparation process to environment and personnel.
Detailed description of the invention
Fig. 1 is the nitrogen Adsorption and desorption isotherms of nitrogen-dopped activated carbon prepared by example 1.
Fig. 2 is the pore size distribution curve of nitrogen-dopped activated carbon prepared by example 1.
Fig. 3 is the nitrogen Adsorption and desorption isotherms of nitrogen-dopped activated carbon prepared by example 2.
Fig. 4 is the pore size distribution curve of nitrogen-dopped activated carbon prepared by example 2.
Fig. 5 is the nitrogen Adsorption and desorption isotherms of nitrogen-dopped activated carbon prepared by example 3.
Fig. 6 is the pore size distribution curve of nitrogen-dopped activated carbon prepared by example 3.
Fig. 7 is the nitrogen Adsorption and desorption isotherms of nitrogen-dopped activated carbon prepared by example 4.
Fig. 8 is the pore size distribution curve of nitrogen-dopped activated carbon prepared by example 4.
Specific embodiment
Embodiment 1:
The discarded cigarette butt collected is after washing drying, and in nitrogen atmosphere, 330 DEG C are carbonized 2 hours；Then will be carbonized abrasive lapping,
After being mixed with aqueous sodium carbonate by carbonized stock with sodium carbonate mass ratio for 1, dried in air dry oven at 80 DEG C；It will mixing
Raw material afterwards is put into tube furnace, and under nitrogen protection, 600 DEG C are carbonized and activate 2 hours；Obtained material is dilute with 3mol/L
Hydrochloric acid solution washs 12 hours under magnetic agitation again, is finally washed with deionized to filtrate pH=6 ~ 7, after filtering at 80 DEG C
The active carbon of N doping, specific surface area 1355m are obtained after drying in air dry oven2/ g, average pore size 1.9nm, nitrogen
Content is 0.7%.
Embodiment 2:
The discarded cigarette butt collected is after washing drying, and in nitrogen atmosphere, 350 DEG C are carbonized 2 hours；Then will be carbonized abrasive lapping,
After being mixed with wet chemical by carbonized stock with potassium carbonate mass ratio for 2, dried in air dry oven at 80 DEG C；It will mixing
Raw material afterwards is put into tube furnace, and under nitrogen protection, 700 DEG C are carbonized and activate 2 hours；Obtained material is dilute with 3mol/L
Hydrochloric acid solution washs 12 hours under magnetic agitation again, is finally washed with deionized to filtrate pH=6 ~ 7, after filtering at 75 DEG C
The active carbon of N doping, specific surface area 1929m are obtained after drying in air dry oven2/ g, average pore size 2.2nm, nitrogen
Content is 0.5%.
Embodiment 3:
The discarded cigarette butt collected is after washing drying, and in nitrogen atmosphere, 350 DEG C are carbonized 2 hours；Then will be carbonized abrasive lapping,
After being mixed with potassium bicarbonate aqueous solution by carbonized stock with saleratus mass ratio for 3, dried in air dry oven at 80 DEG C；It will
Mixed raw material is put into tube furnace, and under nitrogen protection, 750 DEG C are carbonized and activate 2 hours；Obtained material is used
3mol/L dilute hydrochloric acid solution washs 12 hours under magnetic agitation again, is finally washed with deionized to filtrate pH=6 ~ 7, after filtering
The active carbon of N doping, specific surface area 2445m are obtained after drying in air dry oven at 85 DEG C2/ g, average pore size are
2.1nm, nitrogen content 0.4%.
Embodiment 4:
The discarded cigarette butt collected is after washing drying, and in nitrogen atmosphere, 350 DEG C are carbonized 2 hours；Then will be carbonized abrasive lapping,
After being mixed with sodium bicarbonate aqueous solution by carbonized stock with sodium bicarbonate mass ratio for 4, dried in air dry oven at 80 DEG C；It will
Mixed raw material is put into tube furnace, and under nitrogen protection, 800 DEG C are carbonized and activate 2 hours；Obtained material is used
3mol/L dilute hydrochloric acid solution washs 12 hours under magnetic agitation again, is finally washed with deionized to filtrate pH=6 ~ 7, after filtering
The active carbon of N doping, specific surface area 1776m are obtained after drying in air dry oven at 80 DEG C2/ g, average pore size are
2.0nm, nitrogen content 0.2%.
Claims (4)
1. a kind of method for preparing nitrogen-dopped activated carbon using discarded cigarette butt, which is characterized in that specific steps are as follows:
(1) collect discarded cigarette butt raw material washed, drying and processing, then in nitrogen atmosphere, 330 ~ 370 DEG C carbonization 1 ~ 2
Hour；
(2) it by carbonization abrasive lapping obtained in step (1), is mixed with alkali inorganic substance aqueous solution, in forced air drying at 75-85 DEG C
It is dried in case；
(3) material handled through step (2) is put into tube furnace, under nitrogen protection, 600 ~ 800 DEG C are carbonized and activate 1 ~ 2
Hour；
(4) material handled through step (3) is washed 12 ~ 24 hours with 1 ~ 3mol/L dilute hydrochloric acid solution under magnetic stirring, most
After be washed with deionized to filtrate pH=6 ~ 7, filtering, at 75-85 DEG C in air dry oven drying to get N doping is arrived
Active carbon.
2. the method according to claim 1 for preparing nitrogen-dopped activated carbon using discarded cigarette butt, which is characterized in that step
(2) in, the alkali inorganic substance is sodium carbonate, sodium bicarbonate, potassium carbonate and saleratus it is one or more.
3. the method according to claim 1 for preparing nitrogen-dopped activated carbon using discarded cigarette butt, which is characterized in that step
(2) in, the mass ratio of the carbonized stock and alkali inorganic substance is 0.5 ~ 4.0.
4. the method according to claim 1 for preparing nitrogen-dopped activated carbon using discarded cigarette butt, which is characterized in that made
The active carbon of standby N doping, surface area are 1355 ~ 2455 m2/ g, average pore size are distributed as 1.9 ~ 2.2 nm, and nitrogen contains
Amount is 0.2 ~ 0.7%.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110550628A (en) * | 2019-10-21 | 2019-12-10 | 青岛科技大学 | Method for preparing activated carbon for industrial wastewater treatment by one-step method |
| CN110707291A (en) * | 2019-10-21 | 2020-01-17 | 青岛科技大学 | Method for preparing lithium-sulfur battery anode by utilizing recycled carbon material |
| CN111003709A (en) * | 2020-01-03 | 2020-04-14 | 内蒙古昆明卷烟有限责任公司 | Method for preparing activated carbon by using waste cigarette butts, prepared activated carbon and application |
| CN111186837A (en) * | 2020-01-07 | 2020-05-22 | 南京林业大学 | Preparation method of special nitrogen-doped formed activated carbon for catalyst carrier |
| CN111530465A (en) * | 2020-05-26 | 2020-08-14 | 湘潭大学 | Preparation method of supported cigarette end porous carbon material catalyst and application of supported cigarette end porous carbon material catalyst in nitrocyclohexane hydrogenation reaction |
| CN113398977A (en) * | 2021-07-08 | 2021-09-17 | 青岛大学 | Nitrogen-doped carbon catalyst prepared by taking waste cigarette ends as carbon source and preparation method and application thereof |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110550628A (en) * | 2019-10-21 | 2019-12-10 | 青岛科技大学 | Method for preparing activated carbon for industrial wastewater treatment by one-step method |
| CN110707291A (en) * | 2019-10-21 | 2020-01-17 | 青岛科技大学 | Method for preparing lithium-sulfur battery anode by utilizing recycled carbon material |
| CN111003709A (en) * | 2020-01-03 | 2020-04-14 | 内蒙古昆明卷烟有限责任公司 | Method for preparing activated carbon by using waste cigarette butts, prepared activated carbon and application |
| CN111186837A (en) * | 2020-01-07 | 2020-05-22 | 南京林业大学 | Preparation method of special nitrogen-doped formed activated carbon for catalyst carrier |
| CN111530465A (en) * | 2020-05-26 | 2020-08-14 | 湘潭大学 | Preparation method of supported cigarette end porous carbon material catalyst and application of supported cigarette end porous carbon material catalyst in nitrocyclohexane hydrogenation reaction |
| CN113398977A (en) * | 2021-07-08 | 2021-09-17 | 青岛大学 | Nitrogen-doped carbon catalyst prepared by taking waste cigarette ends as carbon source and preparation method and application thereof |
| CN113398977B (en) * | 2021-07-08 | 2023-10-24 | 青岛大学 | Nitrogen-doped carbon catalyst prepared by taking waste cigarette ends as carbon source, and preparation method and application thereof |
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