CN104229787B - The method that native graphite pretreatment is improved preparing graphene by using supercritical fluid productivity - Google Patents
The method that native graphite pretreatment is improved preparing graphene by using supercritical fluid productivity Download PDFInfo
- Publication number
- CN104229787B CN104229787B CN201410478317.6A CN201410478317A CN104229787B CN 104229787 B CN104229787 B CN 104229787B CN 201410478317 A CN201410478317 A CN 201410478317A CN 104229787 B CN104229787 B CN 104229787B
- Authority
- CN
- China
- Prior art keywords
- supercritical fluid
- graphene
- acid
- temperature
- productivity
- 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.)
- Active
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/54—Improvements relating to the production of bulk chemicals using solvents, e.g. supercritical solvents or ionic liquids
Abstract
The method that the present invention relates to native graphite pretreatment is improved preparing graphene by using supercritical fluid productivity, natural graphite powder and acid are joined in container and stirs, addition additive cooling obtain the graphite slurry of low temperature, it is injected to fill in the autoclave of supercritical fluid media and carries out first supercritical processing, then the material after first supercritical processing is quickly injected to normal pressure and produces in batch can, through filtering, separating the material produced in batch can and be dried, obtain Graphene product.Compared with prior art, the low temperature native graphite slurry that acid was anticipated by the application is as charging, with room temperature native graphite as compared with charging, by supercritical fluid stripping process, the productivity of Graphene improves about 2～5 times, the present invention not only increases the productivity of Graphene, and maintains electrical property and the hot property that Graphene has.
Description
Technical field
The invention belongs to technical field of nanometer material preparation, especially relate to native graphite pretreatment is improved super facing
Boundary's fluid prepares the method for Graphene productivity.
Background technology
Due to the special performance of Graphene, thus it is with a wide range of applications in many fields.In order to realize graphite
The commercial applications of alkene, the most critical issue is intended to obtain substantial amounts of high-quality graphene.At present, occur in that many is such as
What prepares the method for Graphene, such as mechanical stripping method, chemical reduction method etc..The graphite that the method for being by mechanically pulling off obtains
Alkene has the electrical property of excellence, but productivity is the lowest；Oxidation-reduction method is capable of Graphene large-scale production,
But, the electrical property of the Graphene obtained is not the most preferable.Supercritical fluid have excellence surface wettability ability,
Low surface tension, high diffusivity coefficient, low-viscosity coefficient, these characteristics facilitate supercritical fluid intercalation and stripping
Graphite, prepares Graphene.Supercritical fluid is peeled off native graphite and is prepared Graphene process, is a thing purely
Reason comes off process, does not introduce other impurity, and therefore, the Graphene obtained has the electrical property of excellence and hot
Energy.But, the productivity of Graphene is not the highest.The present invention proposes the faint low temperature native graphite processed of acid
The raw material that slurry is peeled off as supercritical fluid, prepares Graphene.This invention substantially increases supercritical fluid and peels off
The productivity of Graphene prepared by native graphite, and meanwhile, Graphene has the highest electrical property.
The Chinese patent of Application No. 201210001582.6 discloses supercritical carbon dioxide and peels off preparation large scale
The method of Graphene, uses supercritical CO2For remover, surfactant is dispersant, graphite powder and dispersion
Agent is placed in autoclave, then is passed through CO2, circulating under postcritical state, reduction of blood pressure in high-speed is to normal pressure afterwards,
Repeat said process, make material experience repeatedly boosting and pressure reduction, control stone by controlling boosting and blood pressure lowering number of times
The ink alkene number of plies, i.e. prepares large scale Graphene, but the productivity that the method finally obtains product is relatively low,
This is also that the present invention needs emphatically to solve technical problem.
Summary of the invention
The purpose of the present invention is contemplated to overcome supercritical fluid to peel off native graphite and prepares productivity in Graphene method
Undesirable problem, it is proposed that using the faintest for the acid low temperature native graphite slurry processed as autoclave
Charging, prepares Graphene, substantially increases the productivity of Graphene, and meanwhile, the intrinsic property of Graphene is not the most subject to
To infringement.
The purpose of the present invention can be achieved through the following technical solutions:
The method that native graphite pretreatment is improved preparing graphene by using supercritical fluid productivity, employing following steps:
(1) natural graphite powder and acid joined in container and stir；
(2) filter or separate unnecessary acid, in material, then add additive and stir；
(3) above-mentioned material transferred in low-temperature (low temperature) vessel and lower the temperature, obtaining the graphite slurry of low temperature；
(4) quickly it is injected to low temperature graphite slurry to fill in the autoclave of supercritical fluid media；
(5) control the temperature and pressure of material in autoclave, and material is stopped in autoclave
Carry out first supercritical processing；
(6) material after first supercritical processing is quickly injected to normal pressure produce in batch can；
(7) filter, separate the material produced in batch can and be dried, obtain Graphene product.
In step (1), the weight ratio of natural graphite powder and acid is 1: 10～10: 1, and the acid of employing is that concentration is more than
The sulphuric acid of 70wt%, concentration are more than nitric acid or the concentration hydrochloric acid more than 37wt%, natural graphite powder and the acid of 65wt%
Stir process 5～60 minutes.
Additive described in step (2) is ethylene glycol or ethanol, and addition is the 0.1～5% of graphite powder weight.
In step (3), graphite slurry is cooled to-30～0 DEG C.
Supercritical fluid media described in step (4) includes but not limited to carbon dioxide, ethanol, N-methyl pyrrole
Pyrrolidone, dimethyl acetylamide, 1-dodecyl-2-Pyrrolidone, dimethylformamide, dimethyl sulfoxide, isopropyl
Alcohol, N-octyl group-2-Pyrrolidone, acetone, oxolane, hexamethylene or methanol.
As preferred embodiment, supercritical fluid media can use ethanol, CO2, dimethyl acetylamide,
Oxolane or N-Methyl pyrrolidone.
In step (5) mesohigh reactor, the temperature and pressure of material is close to the critical temperature of supercritical fluid media
And pressure, wherein temperature is 30～390 DEG C, and pressure is 2～40MPa, and material is the time of staying in autoclave
It it is 15～120 minutes.
Wherein, when using carbon dioxide as supercritical fluid media, in autoclave, the temperature of material is
35 DEG C, pressure be 7.5Mpa, residence time of material be 60 minutes；When using ethanol as supercritical fluid media,
Temperature of charge is 245 DEG C, pressure is 6.5Mpa, the time of staying is 50 minutes；Dimethyl acetylamide is supercritical
During fluid media (medium), temperature of charge is 270 DEG C, pressure is 6Mpa, the time of staying is 40 minutes.
Using vacuum drying in step (7), baking temperature is 35～100 DEG C, and drying time is 1～12 hour.
Compared with prior art, the innovative content of patent of the present invention is: (1) is by the pre-place to graphite raw material
Reason improves the productivity of follow-up stripping product；(2) method to pretreatment of raw material is disclosed, by acid treatment and low
The concrete technology that temperature processes；(3) illustrate why pretreatment can improve the principle of productivity, specific as follows:
The raw material that the low temperature native graphite slurry that the present invention utilizes acid to anticipate is peeled off as supercritical fluid,
Owing to the temperature of graphite is relatively low, when being quickly injected in hot environment, can be by strong thermal shock, graphite granule
Generation microexplosion is split by interlayer, and this just provides favourable breach for follow-up molecule intercalation.Secondly, native graphite
After the faint process of peracid, surface is adhered to a number of polarity oxygen-containing functional group (hydroxyl, carboxyl), super
During critical fluids intercalation, polarity oxygen-containing functional group can adsorb supercriticality by bipolarity interattraction
Organic solvent polar molecule, when intercalated molecule is stacked in the passway of the graphite layers of micro rupture, facilitates super
Critical fluids molecule completes intercalation process, substantially increases Graphene productivity.Finally, due to polarity oxygen-containing functional group
Supercritical fluid environment (High Temperature High Pressure) can be reduced, therefore do not affect the intrinsic property of Graphene.
Low temperature native graphite slurry acid anticipated is as charging, with room temperature native graphite as compared with charging, logical
Crossing supercritical fluid stripping process, the productivity of Graphene improves about 2～5 times.The present invention not only increases Graphene
Productivity, and maintain electrical property and the hot property that Graphene has.
Accompanying drawing explanation
Fig. 1 is the AFM figure of the Graphene that the embodiment of the present invention obtains.
Detailed description of the invention
Embodiments of the invention describe in detail as follows, and the present embodiment carries out reality under premised on technical solution of the present invention
Execute, give detailed embodiment and concrete operating process, but protection scope of the present invention is not limited to following
Embodiment.
The method that native graphite pretreatment is improved preparing graphene by using supercritical fluid productivity, employing following steps:
(1) natural graphite powder and acid joined in container and stir, natural graphite powder therein and acid
Weight ratio is 1: 10～10: 1, and the acid of employing is that concentration is more than the sulphuric acid of 70wt%, the concentration nitre more than 65wt%
Sour or that concentration is more than 37wt% hydrochloric acid, natural graphite powder and acid stir process 5～60 minutes；
(2) filter or separate unnecessary acid, in material, then add ethylene glycol or ethanol additive and stir all
Even, addition is the 0.1～5% of graphite powder weight；
(3) above-mentioned material transferred in low-temperature (low temperature) vessel and be cooled to-30～0 DEG C, obtaining the graphite slurry of low temperature；
(4) quickly it is injected to low temperature graphite slurry to fill in the autoclave of supercritical fluid media, permissible
Use supercritical fluid media include carbon dioxide, ethanol, N-Methyl pyrrolidone, dimethyl acetylamide,
1-dodecyl-2-Pyrrolidone, dimethylformamide, dimethyl sulfoxide, isopropanol, N-octyl group-2-Pyrrolidone,
Acetone, oxolane, hexamethylene or methanol；
(5) control the temperature and pressure of material in autoclave close to the critical temperature of supercritical fluid media and
Pressure, and material is stopped in autoclave carry out first supercritical processing, such as, use carbon dioxide to make
During for supercritical fluid media, in autoclave the temperature of material be 35 DEG C, pressure be 7.5Mpa, material stops
Staying the time is 60 minutes；When using ethanol as supercritical fluid media, temperature of charge is 245 DEG C, pressure is
6.5Mpa, the time of staying are 50 minutes；When dimethyl acetylamide is supercritical fluid media, temperature of charge is
270 DEG C, pressure be 6Mpa, the time of staying be 40 minutes；
(6) material after first supercritical processing is quickly injected to normal pressure produce in batch can；
(7) filtering, separate the material produced in batch can and be vacuum dried, baking temperature is 35～100 DEG C, when being dried
Between be 1～12 hour, obtain Graphene product.
Below it is described in detail.
Embodiment 1
Weight ratio by 10: 1, by natural graphite powder and the concentrated sulphuric acid of 95%, joins in container, uses ultrasonic stirring
Mix mode, after stirring 20 minutes, many spent acid are filtered out.By 3% addition ethanol of graphite powder weight, and stir
Mix uniformly.Material is transferred in low-temperature (low temperature) vessel, make material drop to-10 DEG C.Then low-temperature material is quickly sprayed into
In the autoclave filling Supercritical Ethanol, the temperature of autoclave maintains 245 DEG C, and pressure is
6.5MPa.After material stops 60 minutes in autoclave, quickly it is injected to normal pressure and produces in batch can.By material filtering,
Separate, clean, be dried and collect solid product.Solid product joins fresh dimethyl formamide solution again
In, utilize ul-trasonic irradiation to disperse, the time is 120min, stands 12 hours, then uses centrifugation mode
Precipitation is removed by (3000r/min, 10min), finally obtains graphene dispersing solution product.By test analysis table
Bright, material has reached～23% through autoclave cycle Graphene productivity once, more pretreated productivity than raw material
Improve nearly 2.6 times.
Embodiment 2
Weight ratio by 1: 2, by natural graphite powder and the concentrated hydrochloric acid of 80%, joins in container, uses mechanical agitation
Many spent acid, after stirring 40 minutes, are filtered out by mode.By 5% addition ethanol of graphite powder weight, and stir
Uniformly.Material is transferred in low-temperature (low temperature) vessel, make material drop to-20 DEG C.Then low-temperature material is quickly injected to
Filling in the autoclave of supercritical N-Methyl pyrrolidone, the temperature of autoclave maintains 445 DEG C,
Pressure is 4.8MPa.After material stops 90 minutes in autoclave, quickly it is injected to normal pressure and produces in batch can.By thing
Material filters, separates, cleans, is dried and collects solid product.Solid product joins fresh dimethyl methyl again
In amide solution, utilizing ul-trasonic irradiation to disperse, the time is 120min, stands 12 hours, then uses centrifugal point
From mode (3000r/min, 10min), precipitation is removed, finally obtain graphene dispersing solution product.By test
Analysis shows, material has reached～35% through autoclave cycle Graphene productivity once, more preprocessed than raw material
Productivity improve nearly 2.4 times.
Embodiment 3
Weight ratio by 1: 1, by natural graphite powder and the concentrated nitric acid of 90%, joins in container, uses mechanical agitation
Mode, after stirring 50 minutes, separates unnecessary acid centrifuging.By 1% addition ethylene glycol of graphite powder weight,
And stir.Material is transferred in low-temperature (low temperature) vessel, make material drop to-5 DEG C.Then low-temperature material is quickly sprayed
Entering in the autoclave filling supercritical dimethylformamide, the temperature of autoclave maintains 370 DEG C,
Pressure is 6MPa.After material stops 120 minutes in autoclave, quickly it is injected to normal pressure and produces in batch can.By thing
Material filters, separates, cleans, is dried and collects solid product.Solid product joins fresh dimethyl methyl again
In amide solution, utilizing ul-trasonic irradiation to disperse, the time is 120min, stands 12 hours, then uses centrifugal point
From mode (3000r/min, 10min), precipitation is removed, finally obtain graphene dispersing solution product.By test
Analysis shows, material has reached～46% through autoclave cycle Graphene productivity once, more preprocessed than raw material
Productivity improve nearly 3 times.Fig. 1 is the AFM figure of the graphene product that the present embodiment prepares, by this
Bright disclosed pretreatment, can improve the stripping productivity of Graphene, this is because: when low-temperature pulp is quickly injected to
In hot environment, graphite granule interlayer generation microexplosion can be caused to split by strong thermal shock, is very easy to
Molecule intercalation.Secondly, after sour faint process, the polar functional group of attachment on graphite surface, be conducive to absorption to insert
Layer polar molecule；When intercalated molecule is stacked in the passway of the graphite layers of micro rupture, significantly promote intercalation
Speed, thus substantially increase Graphene productivity.
Claims (8)
1. the method that pair native graphite pretreatment improves preparing graphene by using supercritical fluid productivity, it is characterised in that
The method employing following steps:
(1) natural graphite powder and acid joined in container and stir；
(2) filtering or separate unnecessary acid, then add additive in material and stir, described adds
Adding agent is ethylene glycol or ethanol, and addition is the 0.1～5% of graphite powder weight；
(3) above-mentioned material transferred in low-temperature (low temperature) vessel and be cooled to-30～0 DEG C, obtaining the graphite slurry of low temperature；
(4) quickly it is injected to low temperature graphite slurry to fill in the autoclave of supercritical fluid media；
(5) control the temperature and pressure of material in autoclave, and material is stopped in autoclave
Carry out first supercritical processing；
(6) material after first supercritical processing is quickly injected to normal pressure produce in batch can；
(7) filter, separate the material produced in batch can and be dried, obtain Graphene product.
The most according to claim 1 to native graphite pretreatment raising preparing graphene by using supercritical fluid productivity
Method, it is characterised in that in step (1) natural graphite powder and acid weight ratio be 1:10～10:1.
The most according to claim 1 and 2 to native graphite pretreatment raising preparing graphene by using supercritical fluid
The method of productivity, it is characterised in that the acid described in step (1) is that concentration is more than the sulphuric acid of 70wt%, concentration
Nitric acid more than 65wt% or the concentration hydrochloric acid more than 37wt%.
The most according to claim 1 to native graphite pretreatment raising preparing graphene by using supercritical fluid productivity
Method, it is characterised in that natural graphite powder and acid stir process 5～60 minutes in step (1).
The most according to claim 1 to native graphite pretreatment raising preparing graphene by using supercritical fluid productivity
Method, it is characterised in that the supercritical fluid media described in step (4) include carbon dioxide, ethanol,
N-Methyl pyrrolidone, dimethyl acetylamide, 1-dodecyl-2-Pyrrolidone, dimethylformamide, diformazan
Sub-vitriol, isopropanol, N-octyl group-2-Pyrrolidone, acetone, oxolane, hexamethylene or methanol.
The most according to claim 5 to native graphite pretreatment raising preparing graphene by using supercritical fluid productivity
Method, it is characterised in that described supercritical fluid media preferred alcohol, CO2, dimethyl acetylamide, four
Hydrogen furan or N-Methyl pyrrolidone.
The most according to claim 1 to native graphite pretreatment raising preparing graphene by using supercritical fluid productivity
Method, it is characterised in that in step (5) mesohigh reactor, the temperature and pressure of material is close to shooting flow
The critical temperature of body medium and pressure, wherein temperature is 30～390 DEG C, and pressure is 2～40MPa, and material is at high pressure
In reactor, the time of staying is 15～120 minutes.
The most according to claim 1 to native graphite pretreatment raising preparing graphene by using supercritical fluid productivity
Method, it is characterised in that using vacuum drying in step (7), baking temperature is 35～100 DEG C, when being dried
Between be 1～12 hour.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410478317.6A CN104229787B (en) | 2014-09-18 | 2014-09-18 | The method that native graphite pretreatment is improved preparing graphene by using supercritical fluid productivity |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410478317.6A CN104229787B (en) | 2014-09-18 | 2014-09-18 | The method that native graphite pretreatment is improved preparing graphene by using supercritical fluid productivity |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104229787A CN104229787A (en) | 2014-12-24 |
| CN104229787B true CN104229787B (en) | 2016-08-24 |
Family
ID=52218811
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410478317.6A Active CN104229787B (en) | 2014-09-18 | 2014-09-18 | The method that native graphite pretreatment is improved preparing graphene by using supercritical fluid productivity |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104229787B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2999023A1 (en) * | 2015-09-17 | 2017-03-23 | Arisdyne Systems, Inc. | Method of forming graphene material by graphite exfoliation |
| CN105129790B (en) * | 2015-10-10 | 2017-04-05 | 杭州海虹精细化工有限公司 | A kind of method that graphene oxide is prepared under condition of supercritical water |
| CN105645391B (en) * | 2016-01-06 | 2017-12-19 | 大连理工大学 | A kind of CO2Dislocation movement by slip effect is introduced in expanding liquid and peels off the method that natural graphite powder prepares graphene |
| CN107337465A (en) * | 2016-04-29 | 2017-11-10 | 北京化工大学常州先进材料研究院 | A kind of method that supercritical carbon dioxide prepares block CNT porous material |
| CN107335253A (en) * | 2016-04-29 | 2017-11-10 | 北京化工大学常州先进材料研究院 | A kind of method that supercritical carbon dioxide prepares blocky graphite alkene porous material |
| CN114590804A (en) * | 2022-01-26 | 2022-06-07 | 深圳市翔丰华科技股份有限公司 | Method for efficiently preparing doped graphene through supercritical fluid |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8696938B2 (en) * | 2008-08-25 | 2014-04-15 | Nanotek Instruments, Inc. | Supercritical fluid process for producing nano graphene platelets |
| US8691179B2 (en) * | 2011-01-04 | 2014-04-08 | Korea Institute Of Science And Technology | Method for fabricating graphene sheets or graphene particles using supercritical fluid |
| CN102115078B (en) * | 2011-01-19 | 2012-12-26 | 上海交通大学 | Method for preparing graphene by using supercritical fluid |
| CN102515155B (en) * | 2012-01-05 | 2014-01-01 | 上海交通大学 | Method for preparing large-scale graphene through supercritical carbon dioxide exfoliation |
| CN103771401B (en) * | 2013-12-26 | 2015-09-09 | 中国石油大学(北京) | A kind of preparation method of few layer graphene and device |
-
2014
- 2014-09-18 CN CN201410478317.6A patent/CN104229787B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN104229787A (en) | 2014-12-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104229787B (en) | The method that native graphite pretreatment is improved preparing graphene by using supercritical fluid productivity | |
| US10927009B2 (en) | Method for directly preparing expanded graphite or graphene under normal temperature and normal pressure | |
| CN103276590B (en) | Method for preparing super-hydrophobic super-oleophylic cotton | |
| CN103084187B (en) | Carbon-based solid acid and preparation method thereof | |
| CN105585003B (en) | A kind of large-scale continuous preparation method and its equipment of graphene oxide and graphene nanometer sheet | |
| CN104291385A (en) | Nickel cobalt oxide mesoporous microsphere and preparation method thereof | |
| CN105296970B (en) | The method for preparing nitrogen-doped graphene and nickel sulfide quantum dot nano composite | |
| CN105001971B (en) | A kind of method of two-step method production microalgae bio oil | |
| CN102916168B (en) | Modification method of artificial graphite | |
| CN102381697A (en) | Method for preparing spherical carbon material | |
| CN110064367A (en) | A kind of biomass-based activated carbon microballon and its preparation method and application | |
| TW201132594A (en) | Method for recycling solvent of Lyocell fibers | |
| CN103861657A (en) | Preparation method of nano-silver loaded porous silicon dioxide | |
| CN103084188A (en) | Solid acid catalyst containing catalytic active group and adsorption group and preparation and application of solid acid catalyst | |
| CN109626356A (en) | A kind of hollow porous nano charcoal of low cytotoxicity and preparation method thereof | |
| Kim et al. | Comparison of milling modes as a pretreatment method for cellulosic biofuel production | |
| CN105197918A (en) | High-quality graphene and quick preparation method thereof | |
| CN105755579A (en) | Phosphotungstic acid/titanium dioxide composite nano-fibers with ultra-deep desulfurization performance | |
| Qi et al. | Improvement and characterization in enzymatic hydrolysis of regenerated wheat straw dissolved by LiCl/DMAc solvent system | |
| CN103449417A (en) | Preparation method of graphene | |
| CN106554984A (en) | The method for extracting bata-carotene | |
| CN105271388A (en) | Preparation method of high specific surface area ultralong TiO2 nanotube | |
| CN108423655B (en) | Preparation method of fluorine oxidized graphene | |
| CN103832995A (en) | Graphene/carbon nano-tube composite material, preparation method and application thereof | |
| CN116371360A (en) | Magnetic oil tea shell biochar material capable of adsorbing antibiotics and preparation method and application thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |