CN114572969B - Microfluidic reaction system and method for preparing reduced graphene oxide - Google Patents
Microfluidic reaction system and method for preparing reduced graphene oxide Download PDFInfo
- Publication number
- CN114572969B CN114572969B CN202210130006.5A CN202210130006A CN114572969B CN 114572969 B CN114572969 B CN 114572969B CN 202210130006 A CN202210130006 A CN 202210130006A CN 114572969 B CN114572969 B CN 114572969B
- Authority
- CN
- China
- Prior art keywords
- graphene oxide
- reducing agent
- microchannel reactor
- oxide dispersion
- dispersion liquid
- 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
-
- 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
- C01B32/15—Nano-sized carbon materials
- C01B32/182—Graphene
- C01B32/184—Preparation
Abstract
The application provides a microfluidic reaction system, which comprises a plurality of raw material tanks, a microchannel reactor, a filtering device and a plurality of collecting tanks, wherein one part of the raw material tanks are used for storing graphene oxide dispersion liquid, the other part of the raw material tanks are used for storing reducing agent solution, the microchannel reactor is used for inputting the graphene oxide dispersion liquid and the reducing agent solution for mixing and reacting, the filtering device is used for separating solvent containing the reducing agent and reduced graphene oxide products, one part of the collecting tanks is used for collecting reduced graphene oxide filter cakes filtered by the filtering device, and the other part of the collecting tanks is used for collecting mixed solution filtered by the filtering device. The application also provides a method for preparing reduced graphene oxide. The application obviously reduces the occupied space of reaction facilities and continuously prepares the reduced graphene oxide.
Description
Technical Field
The application relates to a microfluidic reaction system and a method for preparing reduced graphene oxide, and belongs to the technical field of reduced graphene oxide preparation.
Background
Graphene is a monoatomic layer two-dimensional material obtained by periodically and repeatedly arranging six-membered rings of carbon atoms, and is widely focused on the excellent electrical, thermal and mechanical properties, so that the graphene is gradually penetrated into the field of multiple industries. The reduction-oxidation graphene method is considered as one of the methods for realizing large-scale production of graphene, and the graphene with a monoatomic layer is obtained by chemically modifying a large number of oxygen-containing functional groups on a graphene sheet layer, weakening interlayer van der Waals effect, stripping and reducing and recovering. Graphene with high single-layer rate can be obtained by a graphene reduction-oxidation method, and the economic benefit is high, but a large number of lattice defects are generated when a large number of oxygen-containing functional groups in the graphene oxide surface and at the edge are removed by reduction, and electron scattering sites are introduced, so that graphene with lower quality and remarkably reduced electric conductivity and thermal conductivity is often obtained.
Thus, reductionUniform and efficient deoxidation in the process is a key for preparing high-quality reduced graphene oxide. Current methods of graphene oxide reduction include thermal reduction, chemical reduction, and electrochemical reduction. The thermal reduction generates high temperature through thermal annealing or microwave radiation, light irradiation and the like, so that oxygen-containing functional groups modified on the Graphene Oxide (GO) are decomposed to generate CO and CO 2 、H 2 O, but the loss of carbon atoms in the process causes cleavage of the carbon sheet and the formation of a large number of lattice defects, typically resulting in small-sized graphene sheets with rich wrinkles. Chemical reduction methods include the use of borohydrides, hydroaluminides, hydrohalic acids, sulfur-containing reducing agents, nitrogen-containing reducing agents, oxygen-containing reducing agents, and the like, with typical reducing agents being hydrazine hydrate, hydroiodic acid, sodium borohydride, ascorbic acid, and the like. According to the method for reducing graphene oxide disclosed in the patent CN104150471A, halogen acid is added into graphene oxide aqueous dispersion, and reflux reaction is carried out at 60-100 ℃ to obtain reduced graphene oxide (rGO) with low oxygen content and a C/O ratio of 19.7-21.9. In addition, the application patent CN105776199A discloses a method for reducing graphene oxide, which adopts mixed liquid of N, N-dimethylbenzylamine and hydrazine hydrate according to the proportion of less than or equal to 1:3 as a reducing agent, and reduces the graphene oxide in an oil bath at 60-80 ℃. The chemical reduction at the present stage can effectively remove most of oxygen-containing functional groups on graphene oxide, but uses a large amount of chemical reagents, and increases the difficulty of cleaning steps and waste liquid treatment. The reaction fluid in the conventional reactor has complex morphology, is difficult to ensure uniform turbulence from the stirring paddle to the reactor wall, increases the morphology and reduction degree difference of the chemically reduced graphene, and brings about quality control problems.
Disclosure of Invention
In view of the above problems, the present application provides a microfluidic reaction system including a plurality of raw material tanks for storing a graphene oxide dispersion liquid, a portion of raw material tanks for storing a reducing agent solution, a microchannel reactor for inputting the graphene oxide dispersion liquid and the reducing agent solution to be mixed and reacted, a filter device for separating a solvent containing a reducing agent and a reduced graphene oxide product, and a plurality of collection tanks for collecting a reduced graphene oxide cake filtered by the filter device, and another portion of collection tanks for collecting a mixed solution filtered by the filter device.
According to one aspect of the present application, the microfluidic reaction system further comprises a plurality of feed pumps for pumping the solution in the feed tank into the microchannel reactor.
According to one aspect of the application, the channels of the microchannel reactor are round section microchannels with a diameter of 100-2000 μm or rectangular microchannels with a side length of 50-2000 μm. The small-size micro-channels limit the raw material sheet diameter of the graphene oxide, so that the remarkably increased pressure drop and the reduced reaction flux are unfavorable for preparation operation and scale; the oversized channels result in an extended mass transfer path for the reactant species within the channels, thereby reducing mixing capacity, and therefore requires selection of appropriate reactor sizes.
Preferably, the method comprises a plurality of micro-channel reactors, wherein the total liquid holdup of the micro-channel reactors is 3-30mL; further preferably, the liquid holdup of a single microchannel reactor is 1.57 or 2.36mL, and the reaction throughput is adjusted by varying the number of microchannel reactors.
According to one aspect of the present application, the graphene oxide dispersion concentration is 1 to 10mg/mL, preferably 1 to 3mg/mL, the graphene oxide dispersion is directly related to the reaction throughput, and the dispersion properties such as viscosity and the like have a significant effect.
According to one aspect of the application, the reducing agent in the reducing agent solution is at least one of sodium borohydride, halogen acid, sodium persulfate, hydrazine hydrate, pyrrole, ethylenediamine, L-ascorbic acid, polyphenols and polyphenolic compounds of plant extracts.
Preferably, the reducing agent is L-ascorbic acid, and the concentration is 0.1-10mg/mL; further preferably, the reducing agent is hydroiodic acid at a concentration of 0.1-10wt.%.
According to one aspect of the present application, the microfluidic reaction system further comprises an oven for drying the reduced graphene oxide filter cake.
The application also provides a method for preparing reduced graphene oxide by using the microfluidic reaction system, which comprises the following steps:
preparing graphene oxide dispersion liquid;
adding the graphene oxide dispersion liquid into a raw material tank, and keeping stirring, wherein the stirring speed is preferably 200-700 revolutions per minute, and the stirring speed ensures that the graphene oxide dispersion liquid is fully stirred and kept uniformly dispersed;
preparing a reducing agent solution;
adding the reducing agent solution to the other raw material tank and maintaining stirring, preferably at a stirring speed of 200-700 revolutions per minute, at a stirring speed that allows the reducing agent solution to be sufficiently stirred and to maintain uniform dispersion;
introducing graphene oxide dispersion liquid and a reducing agent solution into a microchannel reactor, and mixing and reacting the graphene oxide and the reducing agent in the microchannel reactor;
separating a solvent containing a reducing agent and a reduced graphene oxide product by a filtering device, and collecting and cleaning a reduced graphene oxide filter cake;
the above reduced graphene oxide filter cake is dried, preferably at 40-90 ℃ for 4-12 hours.
According to another aspect of the present application, the preparing graphene oxide dispersion liquid includes:
adding graphene oxide into a reaction solvent to obtain graphene oxide dispersion liquid with the concentration of 1-10mg/mL, carrying out ultrasonic treatment on the graphene oxide dispersion liquid, and stirring the graphene oxide dispersion liquid subjected to ultrasonic treatment until the graphene oxide dispersion liquid is uniform.
Preferably, the ultrasonic power of the ultrasonic treatment is 200-1000 watts; preferably, the ultrasonic time of the ultrasonic treatment is 5-30 minutes; the ultrasonic power and the ultrasonic time ensure the uniform dispersion of the graphene oxide solution.
Preferably, the stirring speed is 200-700 revolutions per minute; preferably, the stirring time is 0.5 to 4 hours.
Preferably, the graphene oxide dispersion concentration is 1-3mg/mL; preferably, the reaction solvent is at least one of water, ethanol, N-Dimethylformamide (DMF), N-methylpyrrolidone (NMP), diethyl ether, propylene Carbonate (PC), glacial acetic acid, chloroform and carbon tetrachloride, and further preferably, the reaction solvent is water.
According to another aspect of the present application, the step of preparing the reducing agent solution includes:
dispersing the reducing agent into the reaction solvent to obtain a reducing agent solution.
Preferably, the reducing agent is at least one of sodium borohydride, halogen acid, sodium persulfate, hydrazine hydrate, pyrrole, ethylenediamine, L-ascorbic acid, polyphenols and polyphenol compounds of plant extracts.
Further, preferably, the reducing agent is L-ascorbic acid at a concentration of 0.1-10mg/mL.
In addition, preferably, the reducing agent is hydroiodic acid at a concentration of 0.1-10wt.%.
According to another aspect of the application, the step of introducing the graphene oxide dispersion and the reducing agent solution into the microchannel reactor, the graphene oxide and the reducing agent being mixed and reacted in the microchannel reactor comprises:
controlling the temperature of the microchannel reactor below the boiling point of the dispersion, preferably controlling the temperature to be 30-200 ℃;
introducing graphene oxide dispersion liquid and reducing agent solution into a micro-channel reactor at the same flow rate, wherein the feeding flow rate is 10 mu L/min-5mL/min; preferably, the feed pump has a pumping pressure in the range of 0.1-4MPa, a low flow rate matching the long reaction residence time, but reducing the throughput, the pumping pressure of the present application being in the range of opening the flow path and below the reactor pressure tolerance limit;
graphene oxide and a reducing agent are mixed and reacted in a microchannel reactor.
According to another aspect of the application, the collected reduced graphene oxide filter cake is washed with deionized water, ethanol and acetone a plurality of times, preferably, the reduced graphene oxide filter cake is washed repeatedly 2-4 times, the reduced filter cake contains impurity ions, organic species and the like, and the impurities are removed by washing a plurality of times.
The microchannel reactor replaces the traditional reaction kettle, so that the occupied space of reaction facilities is obviously reduced, and the reduced graphene oxide is continuously prepared. The application utilizes the high-efficiency mass transfer capability and heat transfer efficiency of the microchannel reactor to promote the uniform distribution of the concentration of the reducing agent and the reaction temperature, thereby realizing the controllable preparation of the graphene oxide. The application can change the number of microfluidic reaction systems to realize scale amplification, and the reactors operate independently, thereby avoiding the problems of quality control reduction and thermal management faced by traditional amplification.
Drawings
FIG. 1 is a schematic diagram of a microfluidic reaction system according to the present application;
fig. 2 is an SEM photograph of reduced graphene oxide prepared in example 1;
FIG. 3 is a C1s spectrum of reduced graphene oxide XPS prepared in example 2;
fig. 4 is a comparison result of raman spectra of reduced graphene oxide prepared in example 3 before and after reduction.
Detailed Description
In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more embodiments. It may be evident, however, that such embodiment(s) may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing one or more embodiments.
Fig. 1 is a schematic diagram of a microfluidic reaction system according to the present application, as shown in fig. 1, including: a plurality of head tanks, microchannel reactor 5, filter equipment 6 and a plurality of collection tank, a part of head tanks are used for storing the graphene oxide dispersion, and another part of head tanks are used for storing the reductant solution, the microchannel reactor is used for importing graphene oxide dispersion and reductant solution and mixes and react, filter equipment is used for separating solvent and reduction graphene oxide product that contains the reductant, a part of collection tank is used for collecting the reduction graphene oxide filter cake that filter equipment filtered out, another part of collection tank is used for collecting the mixed solution after the filter equipment filters.
Optionally, a plurality of feed pumps are also included for pumping the solution in the feed tank into the microchannel reactor.
In a preferred embodiment, the microfluidic reaction system comprises a first raw material tank 1, a second raw material tank 2, a first feed pump 3, a second feed pump 4, a microchannel reactor 5, a filtering device 6, a first collecting tank 7 and a second collecting tank 8 which are detachably connected, wherein the first raw material tank 1 is used for adding graphene oxide dispersion liquid, the second raw material tank 2 is used for adding reducing agent solution, the first feed pump is used for pumping the graphene oxide dispersion liquid of the first raw material tank into the microchannel reactor, the second feed pump is used for pumping the reducing agent of the second raw material tank into the microchannel reactor, the microchannel reactor comprises microchannels for reacting graphene oxide and the reducing agent, the inlets of the microchannels are respectively communicated with the first raw material tank and the second raw material tank, the first feed pump is arranged on a pipeline communicated with the first raw material tank, the second feed pump is arranged on a pipeline communicated with the second raw material tank, the outlet of the microchannels is communicated with the filtering device, the outlet of the microchannels is respectively communicated with the filtering device, and the filter cake is respectively filtered by the second collecting tank is used for filtering the filtered cake.
The micro-channel reactor module comprises a plurality of micro-channel reactors, and can be designed and replaced according to the reaction characteristics and the properties of target products, in particular: the channel size, the spatial configuration, the local structure and the like are selected and optimized according to the properties of the target product, including the reduced graphene oxide C/O ratio, the residual functional group types and distribution, the sheet diameter morphology and the like after reduction.
The microchannel reactor is characterized in that the size of the reactor is reduced to the micron level, and the fluid stress is changed from the dominant states of gravity, inertia force and the like to the dominant states of viscous force and interfacial force between media. As the microchannel reactor size decreases, the microchannel reactor interface area increases rapidly, providing efficient heat transfer. Meanwhile, the migration path of the reaction species is greatly shortened, so that the reaction efficiency of a plurality of processes including the organic synthesis reaction is improved by orders of magnitude. Through the configuration optimization design of the microchannel reactor, the efficient reactant mixing capability can be provided, and the rapid mixing and uniform reaction can be realized. The microchannel reactor configuration optimization described above includes: the main channel size and the channel shape (such as barriers, dividing and remixing, continuous bending, decelerating and bending, diameter change, space structure and the like) change the flow distribution and medium stress in the micro-channel, act on parameters including speed distribution, shearing, pressure drop and the like, and finally influence the reaction mass transfer and the reaction operation.
Therefore, the preparation of reduced graphene oxide by adopting a microchannel reactor is one of strategies for solving the problems of discontinuous reduction process, multiple steps and product uniformity of the existing graphene oxide.
The method for preparing the reduced graphene oxide by the microfluidic reaction system comprises the following steps:
preparing graphene oxide dispersion liquid;
adding the graphene oxide dispersion liquid into a raw material tank, and keeping stirring;
preparing a reducing agent solution;
adding the reducing agent solution into another raw material tank, and keeping stirring;
introducing graphene oxide dispersion liquid and a reducing agent solution into a microchannel reactor, and mixing and reacting the graphene oxide and the reducing agent in the microchannel reactor;
separating a solvent containing a reducing agent and a reduced graphene oxide product by a filtering device, and collecting and cleaning a reduced graphene oxide filter cake;
and drying the reduced graphene oxide filter cake.
In one embodiment, the graphene oxide dispersion is obtained by dispersing graphene oxide in a reaction solvent. The method for preparing the reduced graphene oxide by the microfluidic reaction system is suitable for graphene oxides with different oxygen contents, sheet diameters and monolayer rates.
Preferably, graphene oxide is prepared by Hummers method and other chemical oxidation and electrochemical oxidation.
Preferably, the method for preparing the graphene oxide dispersion liquid comprises adding graphene oxide into a solvent to obtain uniform graphene oxide dispersion liquid with the concentration of 1-10mg/mL, and carrying out ultrasonic treatment on the dispersion liquid, wherein the ultrasonic power is 200-1000 watts, the ultrasonic time is 5-30 minutes, the stirring is carried out until the graphene oxide dispersion liquid is uniform, the stirring rotating speed is 200-700 revolutions per minute, and the stirring time is 0.5-4 hours.
In one embodiment, the step of introducing the graphene oxide dispersion and the reducing agent solution into the microchannel reactor, the graphene oxide and the reducing agent being mixed and reacted in the microchannel reactor comprises:
step 1: firstly, adding graphene oxide dispersion liquid into a first raw material tank, and keeping stirring at a stirring rotating speed of 200-700 revolutions per minute; the reducing agent solution was then added to the second feed tank, again with stirring, at 200-700 revolutions per minute.
Step 2: the temperature of the micro-channel reactor is controlled to be 30-200 ℃ and controlled to be below the boiling point of the dispersion liquid. And then introducing the graphene oxide dispersion liquid and the reducing agent solution into the microchannel reactor at the same flow rate, wherein the feeding flow rate of each inlet is 10 mu L/min-5mL/min, the pumping pressure range is 0.1-4MPa, and the graphene oxide and the reducing agent are mixed and reacted in the microchannel reactor.
Wherein the micro-channel reactor is a circular section micro-channel with the channel diameter of 100-2000 mu m or a rectangular channel with the side length of 50-2000 mu m, and the total liquid holdup of the micro-channel reactor is 3-30mL.
Step 3: the outlet of the micro-channel is connected with a filtering device, a solvent containing a reducing agent and a reduced graphene oxide product are separated, and the collected reduced graphene oxide filter cake is cleaned by deionized water, ethanol and acetone and is repeated for 2-4 times.
Step 4: transferring the cleaned reduced graphene oxide filter cake into an oven, and drying at 40-90 ℃ for 4-12 hours.
In the above embodiments, the reducing agent is sodium borohydride, halogen acid, sodium persulfate, hydrazine hydrate, pyrrole, ethylenediamine, L-ascorbic acid, polyphenols and polyphenol compounds in plant extracts such as tea, etc.; the reaction solvent is at least one of water, ethanol, N-Dimethylformamide (DMF), N-methylpyrrolidone (NMP), diethyl ether, propylene Carbonate (PC), glacial acetic acid, chloroform and carbon tetrachloride.
Preferably, the graphene oxide dispersion concentration is 1-3mg/mL.
Preferably, L-ascorbic acid is selected as a reducing agent, and the concentration range is 0.1-10mg/mL; or hydroiodic acid as a reducing agent at a concentration of 0.1-10wt.%.
Aiming at the problems that the existing graphene oxide reduction process is slow in reaction, complex in preparation steps, difficult to continuously produce, uniform in quality of the product reduced graphene oxide and the like, the application provides efficient mixing and mass and heat transfer by utilizing a microfluidic technology, promotes species transportation in the reaction process and improves the microscopic distribution uniformity of fluid. The method provides a high-efficiency safe and easily-amplified reduction graphene oxide technology, which can shorten the reduction time to less than 20 minutes, and realizes high-quality uniform production of reduction graphene oxide and continuous reduction process by utilizing uniform fluid form distribution in the micro-channel reactor. In addition, the method can be combined with graphene oxide microflow control equipment, post-treatment and the like to construct a multifunctional continuous graphene oxide preparation platform.
Various embodiments according to the present application will be described in detail below.
Example 1
Graphene oxide dispersion: the graphene oxide aqueous dispersion was formulated at 1mg/mL and then sonicated at 200W for 30 minutes.
Reducing agent: 3.6wt.% aqueous hydroiodic acid.
Microchannel reactor: the single microchannel reactor hold-up was 1.57mL.
Controlling the temperature of the microchannel reactor to be 60 ℃, pumping graphene oxide dispersion liquid and hydroiodic acid aqueous solution into the microchannel reactor group at the flow rate of 428 mu L/min respectively, wherein the corresponding residence time is 9.2min, connecting a suction filtration device to a microchannel outlet, separating a product reduced graphene oxide filter cake, washing the product reduced graphene oxide filter cake with deionized water, ethanol and acetone three times, and drying the product in a 60 ℃ oven for 6 hours to prepare reduced graphene oxide as shown in figure 2.
Example 2
Graphene oxide dispersion: the graphene oxide aqueous dispersion was formulated at 1mg/mL and then sonicated at 200W for 30 minutes.
Reducing agent: 0.88mg/mL of L-ascorbic acid in water.
Microchannel reactor: the single microchannel reactor hold-up was 2.36mL.
Controlling the temperature of a microchannel reactor to be 90 ℃, pumping graphene oxide dispersion liquid and hydroiodic acid aqueous solution into the microchannel reactor group at a flow rate of 530 mu L/min respectively, wherein the corresponding residence time is 11.1min, the outlet of the microchannel is connected with a suction filtration device, a product reduction graphene oxide filter cake is separated, deionized water, ethanol and acetone are used for cleaning three times, and then drying is carried out in a 60 ℃ oven for 6 hours, the prepared reduction graphene oxide is shown in a graph in FIG. 3, the fact that the graphene oxide is effectively reduced is clearly seen from an XPS graph in FIG. 3, the reduction can be carried out in 11.1min, and compared with the condition in a beaker under the same reducing agent and similar temperature, the time required for the reduction of the microchannel is shorter.
Example 3
Graphene oxide dispersion: the graphene oxide aqueous dispersion was formulated at 2mg/mL and then sonicated at 200W for 30 minutes.
Reducing agent: 1.76mg/mL of L-ascorbic acid in water.
Microchannel reactor: the single microchannel reactor hold-up was 1.57mL.
Controlling the temperature of the microchannel reactor to 90 ℃, pumping graphene oxide dispersion liquid and hydroiodic acid aqueous solution into the microchannel reactor group at a flow rate of 485 mu L/min respectively, wherein the corresponding residence time is 12.1min, connecting a suction filtration device to a microchannel outlet, separating a product reduced graphene oxide filter cake, washing the product reduced graphene oxide filter cake with deionized water, ethanol and acetone for three times, and drying the product in a 60 ℃ oven for 6 hours, wherein the prepared reduced graphene oxide is shown in figure 4, and the reduction graphene oxide is shown to be reduced effectively.
The application realizes the efficient continuous reduction of the graphene oxide, and the reduction time can be reduced to 5-20min. The accurate regulation of the oxygen content of the reduced graphene oxide can be realized by regulating reaction parameters such as reaction temperature, concentration of a reducing agent and the like or fluid parameters including flow rate, reaction time, microchannel configuration and the like.
Finally, it should be noted that: the foregoing description is only a preferred embodiment of the present application, and the present application is not limited thereto, but it is to be understood that modifications and equivalents of some of the technical features described in the foregoing embodiments may be made by those skilled in the art, although the present application has been described in detail with reference to the foregoing embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.
Claims (23)
1. The microfluidic reaction system is characterized by comprising a plurality of raw material tanks, a microchannel reactor, a filtering device and a plurality of collecting tanks, wherein one part of the raw material tanks are used for storing graphene oxide dispersion liquid, the other part of the raw material tanks are used for storing reducing agent solution, the microchannel reactor is used for inputting graphene oxide dispersion liquid and the reducing agent solution for mixing and reacting, the filtering device is used for separating solvent containing the reducing agent and reduced graphene oxide products, one part of the collecting tanks is used for collecting reduced graphene oxide filter cakes filtered by the filtering device, the other part of the collecting tanks is used for collecting mixed solution filtered by the filtering device, and the concentration of the graphene oxide dispersion liquid is 1-10mg/mL; the reducing agent is L-ascorbic acid with the concentration of 0.1-10mg/mL, or the reducing agent is hydroiodic acid with the concentration of 0.1-10 wt%; the microchannel reactor module comprises a plurality of microchannel reactors, and the microchannel reactor module is designed and replaced according to the reaction characteristics and the properties of target products, and comprises: the method comprises the steps of selecting and optimizing channel size, space configuration and local structure according to the properties of target products including reduced graphene oxide C/O ratio, residual functional group types and distribution and sheet diameter morphology, wherein the channels of the microchannel reactor are round section microchannels with the diameter of 100-2000 mu m or rectangular microchannels with the side length of 50-2000 mu m, the total liquid holdup of a plurality of microchannel reactors is 3-30mL, and the liquid holdup of a single microchannel reactor is 1.57 or 2.36mL.
2. The microfluidic reaction system of claim 1, further comprising a plurality of feed pumps for pumping the solution in the feed tank into the microchannel reactor.
3. The microfluidic reaction system of claim 2, wherein the feed pump has a pumping pressure in the range of 0.1-4MPa.
4. The microfluidic reaction system of claim 1, wherein the graphene oxide dispersion concentration is 1-3mg/mL.
5. The microfluidic reaction system of claim 1, further comprising an oven for drying the reduced graphene oxide filter cake.
6. A method of preparing reduced graphene oxide using the microfluidic reaction system of any one of claims 1-5, comprising:
preparing graphene oxide dispersion liquid;
adding the graphene oxide dispersion liquid into a raw material tank, and keeping stirring;
preparing a reducing agent solution;
adding the reducing agent solution into another raw material tank, and keeping stirring;
introducing graphene oxide dispersion liquid and a reducing agent solution into a microchannel reactor, and mixing and reacting the graphene oxide and the reducing agent in the microchannel reactor;
separating a solvent containing a reducing agent and a reduced graphene oxide product by a filtering device, and collecting and cleaning a reduced graphene oxide filter cake;
and drying the reduced graphene oxide filter cake.
7. The method of claim 6, wherein the step of adding the reducing agent solution to the additional feedstock tank while maintaining agitation is performed at a rotational speed of 200 to 700 revolutions per minute.
8. The method of claim 6, wherein the step of adding the graphene oxide dispersion to the feedstock tank while maintaining agitation is performed at a rotational speed of 200 to 700 revolutions per minute.
9. The method according to claim 6, wherein the step of drying the reduced graphene oxide cake is performed at 40 to 90 ℃ for 4 to 12 hours.
10. The method of claim 6, wherein the step of preparing a graphene oxide dispersion comprises:
adding graphene oxide into a reaction solvent to obtain graphene oxide dispersion liquid with the concentration of 1-10mg/mL, carrying out ultrasonic treatment on the graphene oxide dispersion liquid, and stirring the graphene oxide dispersion liquid subjected to ultrasonic treatment until the graphene oxide dispersion liquid is uniform.
11. The method of claim 10, wherein the ultrasonic power of the ultrasonic treatment is 200-1000 watts.
12. The method of claim 10, wherein the sonication is carried out for a period of time of from 5 to 30 minutes.
13. The method of claim 10, wherein the agitation is at a speed of 200 to 700 revolutions per minute.
14. The method of claim 10, wherein the stirring time is 0.5 to 4 hours.
15. The method of claim 10, wherein the graphene oxide dispersion concentration is 1-3mg/mL.
16. The method of claim 10, wherein the reaction solvent is at least one of water, ethanol, N-Dimethylformamide (DMF), N-methylpyrrolidone (NMP), diethyl ether, propylene Carbonate (PC), glacial acetic acid, chloroform, and carbon tetrachloride.
17. The method of claim 10, wherein the reaction solvent is water.
18. The method of claim 6, wherein the step of preparing a reducing agent solution comprises:
dispersing the reducing agent into the reaction solvent to obtain a reducing agent solution.
19. The method of claim 6, wherein the step of introducing the graphene oxide dispersion and the reducing agent solution into the microchannel reactor, the graphene oxide and the reducing agent being mixed and reacted in the microchannel reactor comprises:
controlling the temperature of the microchannel reactor to be below the boiling point of the dispersion; introducing graphene oxide dispersion liquid and a reducing agent solution into a microchannel reactor at the same flow rate; graphene oxide and a reducing agent are mixed and reacted in a microchannel reactor.
20. The method of claim 19, wherein the temperature is controlled to be 30-200 ℃.
21. The method of claim 19, wherein the feed flow rate is from 10 μl/min to 5mL/min.
22. The method of claim 6, wherein the collected reduced graphene oxide filter cake is washed multiple times with deionized water, ethanol, and acetone.
23. The method of claim 22, wherein the reducing graphene oxide filter cake is repeated 2-4 times.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210130006.5A CN114572969B (en) | 2022-02-11 | 2022-02-11 | Microfluidic reaction system and method for preparing reduced graphene oxide |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210130006.5A CN114572969B (en) | 2022-02-11 | 2022-02-11 | Microfluidic reaction system and method for preparing reduced graphene oxide |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114572969A CN114572969A (en) | 2022-06-03 |
| CN114572969B true CN114572969B (en) | 2023-08-18 |
Family
ID=81770718
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210130006.5A Active CN114572969B (en) | 2022-02-11 | 2022-02-11 | Microfluidic reaction system and method for preparing reduced graphene oxide |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114572969B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114956188B (en) * | 2022-06-19 | 2023-09-29 | 安徽大学 | Method for continuously preparing manganese dioxide with specific crystal form by microfluidic control |
| CN115507307A (en) * | 2022-09-12 | 2022-12-23 | 西南石油大学 | Hydrogen leakage monitoring and response system of hydrogen mixing system |
| CN115738950A (en) * | 2022-12-14 | 2023-03-07 | 中国科学技术大学 | Micro-fluidic-based graphene continuous preparation and assembly micro-system and application |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102408107A (en) * | 2010-09-26 | 2012-04-11 | 中国科学院上海硅酸盐研究所 | Method for preparing high-quality graphene |
| CN103387226A (en) * | 2013-07-05 | 2013-11-13 | 清华大学深圳研究生院 | Preparation method for graphene |
| CN105692608A (en) * | 2016-04-22 | 2016-06-22 | 四川农业大学 | Method for preparing graphene through one step of oxidation and reduction |
| CN106145097A (en) * | 2016-06-13 | 2016-11-23 | 南京工业大学 | The preparation method of the redox graphene that a kind of hydrophilic and hydrophobic is controlled |
| CN107001047A (en) * | 2014-12-12 | 2017-08-01 | 株式会社Lg化学 | Partial oxidation of graphite alkene and preparation method thereof |
| CN110117003A (en) * | 2018-02-05 | 2019-08-13 | 庄鹏宇 | A kind of preparation method of redox graphene film |
| KR102143528B1 (en) * | 2019-06-25 | 2020-08-11 | 충남대학교산학협력단 | Continuous Microfluidic Reactor for High-Temperature Reaction and Preparation Method for Indole Derivatives Using the Reactor |
| CN112774596A (en) * | 2021-02-10 | 2021-05-11 | 中国科学技术大学先进技术研究院 | Equipment for preparing graphene oxide through microfluidics |
| CN112811417A (en) * | 2021-02-10 | 2021-05-18 | 中国科学技术大学先进技术研究院 | Method for preparing graphene oxide through microfluidics |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107615031B (en) * | 2015-03-24 | 2020-09-01 | 新加坡国立大学 | Resistance type microfluid pressure sensor |
-
2022
- 2022-02-11 CN CN202210130006.5A patent/CN114572969B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102408107A (en) * | 2010-09-26 | 2012-04-11 | 中国科学院上海硅酸盐研究所 | Method for preparing high-quality graphene |
| CN103387226A (en) * | 2013-07-05 | 2013-11-13 | 清华大学深圳研究生院 | Preparation method for graphene |
| CN107001047A (en) * | 2014-12-12 | 2017-08-01 | 株式会社Lg化学 | Partial oxidation of graphite alkene and preparation method thereof |
| CN105692608A (en) * | 2016-04-22 | 2016-06-22 | 四川农业大学 | Method for preparing graphene through one step of oxidation and reduction |
| CN106145097A (en) * | 2016-06-13 | 2016-11-23 | 南京工业大学 | The preparation method of the redox graphene that a kind of hydrophilic and hydrophobic is controlled |
| CN110117003A (en) * | 2018-02-05 | 2019-08-13 | 庄鹏宇 | A kind of preparation method of redox graphene film |
| KR102143528B1 (en) * | 2019-06-25 | 2020-08-11 | 충남대학교산학협력단 | Continuous Microfluidic Reactor for High-Temperature Reaction and Preparation Method for Indole Derivatives Using the Reactor |
| CN112774596A (en) * | 2021-02-10 | 2021-05-11 | 中国科学技术大学先进技术研究院 | Equipment for preparing graphene oxide through microfluidics |
| CN112811417A (en) * | 2021-02-10 | 2021-05-18 | 中国科学技术大学先进技术研究院 | Method for preparing graphene oxide through microfluidics |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114572969A (en) | 2022-06-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN114572969B (en) | Microfluidic reaction system and method for preparing reduced graphene oxide | |
| KR101727939B1 (en) | Surface treating method using Tayler Reactor | |
| KR101573384B1 (en) | Graphene oxide manufaturing system using couette-taylor reactor and method thereof | |
| EP1803497A1 (en) | Method of manufacturing nonoparticles | |
| CN109679690A (en) | A kind of liquid-phase hydrogenatin system and liquid phase hydrogenating method | |
| CN103816945A (en) | Continuous catalyst production process and equipment | |
| CN101875490B (en) | Method for synthesizing carbon micron-spheres | |
| CN107215868A (en) | The method that the graphene product of high-purity is prepared using oxidation-reduction method Fast Purification | |
| CN103613126A (en) | Method and system for removing vanadium impurities in titanium tetrachloride | |
| CN112811417A (en) | Method for preparing graphene oxide through microfluidics | |
| CN110420659B (en) | Device and method for catalytic oxidation of magnesium sulfite, cobalt nitrate/ZSM-5 molecular sieve catalyst and preparation method thereof | |
| CN211725714U (en) | High-throughput micro-reaction equipment for preparing di-tert-butyl peroxide | |
| CN110203918B (en) | Aminated graphene and preparation method thereof | |
| CN110229073A (en) | A method of 4,4 '-diaminodiphenyl ethers are prepared using microchannel continuous flow reactor | |
| CN207951455U (en) | A kind of high-molecular chelating agent aminodithioformic acid polyethyleneimine synthetic reaction device | |
| CN110639415A (en) | Continuous dispersion system, catalyst batch synthesis device and method | |
| CN112499592A (en) | System and process for preparing hydrogen peroxide based on anthraquinone method | |
| CN107352531A (en) | A kind of method that micro crystal graphite prepares graphene | |
| DE102008010744A1 (en) | Reduction of silica | |
| CN206089050U (en) | Carbon nanotube purification system of retrieval and utilization heat energy | |
| CN115254173B (en) | Graphite-phase carbon nitride photocatalyst, and preparation method, system and application thereof | |
| CN208554115U (en) | A kind of alpha-olefin hydroformylation reaction prepares the heterophase reactor of aldehyde | |
| CN106167259B (en) | The Carbon nanotube purification system of precipitate metal ion | |
| CN103551086A (en) | Hydrogenation reaction device for refining caprolactam | |
| CN109912007B (en) | Degradation method and degradation system for organic wastewater |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |