CN114572969A - Microfluidic reaction system and method for preparing reduced graphene oxide - Google Patents
Microfluidic reaction system and method for preparing reduced graphene oxide Download PDFInfo
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Abstract
The invention 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 to mix and react, the filtering device is used for separating a solvent containing a reducing agent and a reduced graphene oxide product, one part of the collecting tanks are used for collecting reduced graphene oxide filter cakes filtered by the filtering device, and the other part of the collecting tanks are used for collecting mixed solution filtered by the filtering device. The invention also provides a method for preparing the reduced graphene oxide. The invention obviously reduces the occupied space of reaction facilities and continuously prepares the reduced graphene oxide.
Description
Technical Field
The invention 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 two-dimensional material with a single atomic layer, which is obtained by periodically and repeatedly arranging six-membered rings of carbon atoms, and has been gradually permeated into multiple industrial fields due to the wide attention on excellent electrical, thermal and mechanical properties. The reduced graphene oxide method is considered to be one of the methods which are most easy to realize large-scale production of graphene, and a large number of oxygen-containing functional groups are chemically modified on a graphite sheet layer, so that the van der waals effect between layers is weakened, and the graphene is peeled off and reduced to recover to obtain single atomic layer graphene. The graphene reduction and oxidation method can obtain graphene with high single-layer rate and high economic benefit, but a large number of lattice defects are generated when a large number of oxygen-containing functional groups in the surface and at the edge of the graphene oxide are removed through reduction, and the graphene with lower quality and remarkably reduced electric and thermal conductivity is obtained by introducing electron scattering sites.
Therefore, the uniform and efficient deoxidation in the reduction process is the key for preparing the high-quality reduced graphene oxide. Current graphene oxide reduction methods 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 the modified oxygen-containing functional group on the Graphene Oxide (GO) is decomposed to generate CO and CO2、H2O, etc., but loss of carbon atoms in the process causes cleavage of the carbon sheet layer and formation of a large number of lattice defects, typically resulting in small-sized graphene sheets with abundant wrinkles. Chemical reduction methods include the use of borohydrides, aluminum hydrides, hydrohalic acids, sulfur-containing reducing agents, nitrogen-containing reducing agents, oxygen-containing reducing agents, and the like, with hydrazine hydrate, hydroiodic acid, sodium borohydride, ascorbic acid, and the like being typical reducing agents. For example, the invention patent "CN 104150471A a method for reducing graphene oxide" adds halogen acid into graphene oxide aqueous dispersion, and performs reflux reaction at 60-100 ℃ to obtain reduced graphene oxide (rGO) with low oxygen content and C/O ratio of 19.7-21.9. In addition, the invention patent "CN 105776199A a method for reducing graphene oxide" adopts a mixed solution of N, N-dimethylbenzylamine and hydrazine hydrate in a ratio of less than or equal to 1:3 as a reducing agent, and reduces the graphene oxide in an oil bath at 60-80 ℃. Most of oxygen-containing functional groups on the graphene oxide can be effectively removed by chemical reduction at the present stage, but a large amount of chemical reagents are used, and the difficulty of cleaning steps and waste liquid treatment is increased. The reaction fluid in the conventional reactor has complex shape and is difficult to ensure from the stirring paddle to the reactionThe wall of the reactor is uniform and turbulent, so that the difference of the appearance and the reduction degree of the chemically reduced graphene is increased, and the quality control problem is caused.
Disclosure of Invention
In view of the above problems, the present invention provides a microfluidic reaction system, including a plurality of raw material tanks, a microchannel reactor, a filtering device, and a plurality of collection tanks, where one part of the raw material tanks is used to store a graphene oxide dispersion liquid, the other part of the raw material tanks is used to store a reducing agent solution, the microchannel reactor is used to input the graphene oxide dispersion liquid and the reducing agent solution to mix and react, the filtering device is used to separate a solvent containing a reducing agent and a reduced graphene oxide product, the one part of the collection tanks is used to collect a reduced graphene oxide filter cake filtered by the filtering device, and the other part of the collection tanks is used to collect a mixed solution filtered by the filtering device.
According to an aspect of the invention, the above 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 invention, the channel of the microchannel reactor is a circular section microchannel with the diameter of 100-2000 μm or a rectangular microchannel with the side length of 50-2000 μm. The small-size micro-channel limits the raw material sheet diameter of the graphene oxide, and the obviously increased pressure drop and the reduced reaction flux are not beneficial to preparation operation and large-scale production; excessive channel size results in prolonged mass transfer paths of reactant species within the channels, thereby reducing mixing capacity, and thus requires selection of appropriate reactor dimensions.
Preferably, the device comprises a plurality of microchannel reactors, and the total liquid holdup of the microchannel reactors is 3-30 mL; further preferably, the liquid hold-up of a single microchannel reactor is 1.57 or 2.36mL, and the reaction throughput is adjusted by changing the number of microchannel reactors.
According to an aspect of the present invention, the graphene oxide dispersion has a concentration of 1-10mg/mL, preferably 1-3mg/mL, and the graphene oxide dispersion is directly related to the reaction throughput and has a significant effect on the dispersion properties such as viscosity and the like.
According to one aspect of the invention, the reducing agent in the reducing agent solution is at least one of sodium borohydride, hydrohalic acid, sodium persulfate, hydrazine hydrate, pyrrole, ethylenediamine, L-ascorbic acid, and polyphenols and polyphenolic compounds of plant extracts.
Preferably, the reducing agent is L-ascorbic acid with the concentration of 0.1-10 mg/mL; further preferably, the reducing agent is hydroiodic acid at a concentration of 0.1 to 10 wt.%.
According to an aspect of the invention, the above microfluidic reaction system further comprises an oven for drying the reduced graphene oxide filter cake.
The invention also provides a method for preparing reduced graphene oxide by using the microfluidic reaction system, which comprises the following steps:
preparing a graphene oxide dispersion liquid;
adding the graphene oxide dispersion liquid into a raw material tank, and keeping stirring, preferably, the stirring speed is 200-700 rpm, and the stirring speed enables the graphene oxide dispersion liquid to be fully stirred and keeps uniform dispersion;
preparing a reducing agent solution;
adding the reducing agent solution into the other raw material tank and keeping stirring, preferably, the stirring speed is 200-700 revolutions per minute, and the stirring speed enables the reducing agent solution to be fully stirred and keeps uniform dispersion;
introducing the 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 the solvent containing the reducing agent and the reduced graphene oxide product by a filtering device, collecting and cleaning a reduced graphene oxide filter cake;
and drying the reduced graphene oxide filter cake, preferably, drying at 40-90 ℃ for 4-12 hours.
According to another aspect of the present invention, the step of preparing the graphene oxide dispersion liquid includes:
adding graphene oxide into a reaction solvent to obtain a 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 and 1000 watts; preferably, the sonication time of the sonication 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 rpm; preferably, the stirring time is 0.5 to 4 hours.
Preferably, the concentration of the graphene oxide dispersion liquid is 1-3 mg/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 invention, the step of preparing the reducing agent solution comprises:
the reducing agent is dispersed in the reaction solvent to obtain a reducing agent solution.
Preferably, the reducing agent is at least one of sodium borohydride, hydrohalic acid, sodium persulfate, hydrazine hydrate, pyrrole, ethylenediamine, L-ascorbic acid, and polyphenol and polyphenolic compounds of plant extracts.
Further, preferably, the reducing agent is L-ascorbic acid with a concentration of 0.1-10 mg/mL.
Further, preferably, the reducing agent is hydroiodic acid at a concentration of 0.1 to 10 wt.%.
According to another aspect of the present invention, the step of introducing the graphene oxide dispersion and the reducing agent solution into the microchannel reactor, wherein the graphene oxide and the reducing agent are mixed and reacted in the microchannel reactor comprises:
controlling the temperature of the microchannel reactor to be below the boiling point of the dispersion liquid, preferably controlling the temperature to be 30-200 ℃;
introducing the graphene oxide dispersion liquid and the reducing agent solution into a microchannel reactor at the same flow rate, wherein the preferable feeding flow rate is 10 mu L/min-5 mL/min; preferably, the pumping pressure range of the feed pump is 0.1-4MPa, the low flow rate is matched with the long reaction residence time, but the treatment flux is reduced, and the pumping pressure range of the feed pump is an open flow path and is lower than the pressure resistance limit of the reactor;
the graphene oxide and the reducing agent are mixed and reacted in the microchannel reactor.
According to another aspect of the present invention, the collected reduced graphene oxide filter cake is washed with deionized water, ethanol and acetone for a plurality of times, preferably, the washing of the reduced graphene oxide filter cake is repeated 2 to 4 times, and the reduced graphene oxide filter cake contains impurity ions, organic species, etc., and is washed for a plurality of times to remove impurities.
The microchannel reactor replaces the traditional reaction kettle, obviously reduces the occupied space of reaction facilities, and continuously prepares the reduced graphene oxide. According to the invention, the uniform distribution of the concentration of the reducing agent and the reaction temperature is promoted by utilizing the high-efficiency mass transfer capacity and the heat transfer efficiency of the microchannel reactor, so that the controllable preparation of the graphene oxide is realized. The invention can change the number of the microfluidic reaction systems to realize scale amplification, and the reactors operate independently, thereby avoiding the problems of quality control reduction and thermal management in the traditional amplification.
Drawings
FIG. 1 is a schematic diagram of a microfluidic reaction system according to the present invention;
fig. 2 is an SEM photograph of the reduced graphene oxide prepared in example 1;
FIG. 3 is a C1s spectrum of XPS of reduced graphene oxide prepared in example 2;
fig. 4 is a comparison result of raman spectra before and after reduction of the reduced graphene oxide prepared in example 3.
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 view of a microfluidic reaction system according to the present invention, as shown in fig. 1, including: a plurality of head tanks, microchannel reactor 5, filter equipment 6 and a plurality of holding vessel, some head tanks are used for storing graphite oxide dispersion, and another part head tank is used for storing reducing agent solution, the microchannel reactor is used for importing graphite oxide dispersion and reducing agent solution and mixes and react, filter equipment is used for separating the solvent that contains the reducing agent and reduces the graphite oxide product, some holding vessel is used for collecting the graphite oxide filter cake that filter equipment filtered, another part holding vessel is used for collecting the mixed solution after filter equipment filters.
Optionally, a plurality of feed pumps are 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 a graphene oxide dispersion liquid, the second raw material tank 2 is used for adding a 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 a microchannel for reacting the graphene oxide and the reducing agent, inlets of the microchannels are respectively communicated with the first raw material tank and the second raw material tank, a first feed pump is installed on a pipeline of the microchannel communicated with the first raw material tank, install the second charge pump on the pipeline of microchannel and second head tank intercommunication, the export and the filter equipment intercommunication of microchannel, filter equipment's export communicates with first holding vessel and second holding vessel respectively, first holding vessel is used for collecting the mixed solution after filter equipment filters, the second holding vessel is used for collecting the reduced graphene oxide filter cake that filter equipment filtered out.
The microchannel reactor module comprises a plurality of microchannel reactors, and can be designed and replaced according to the reaction characteristics and the properties of target products, specifically: selecting and optimizing the channel size, the spatial configuration, the local structure and the like according to the properties of the target product, including the reduced graphene oxide C/O ratio, the types and the distribution of residual functional groups, the sheet diameter morphology and the like after reduction.
The microchannel reactor is characterized in that the size of the reactor is reduced to micron level, and the fluid stress is converted into a state that the viscous force and interfacial force between media are dominant from the dominance of gravity, inertia force and the like. As microchannel reactor size decreases, the microchannel reactor interfacial 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 organic synthesis reaction is improved by orders of magnitude. Through the configuration optimization design of the microchannel reactor, the efficient reactant mixing capacity can be provided, and the rapid mixing and uniform reaction can be realized. The configuration optimization of the microchannel reactor comprises the following steps: the size of the main channel and the shape of the channel (such as obstacles, dividing heavy convergence, continuous bending, decelerating bending, changing the diameter, spatial structure and the like) so as to change the flow state 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 the microchannel reactor is one of the strategies for solving the problems of discontinuous reduction process, multiple steps and product uniformity of the conventional graphene oxide.
The method for preparing the reduced graphene oxide by using the microfluidic reaction system comprises the following steps:
preparing a 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 the 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 the solvent containing the reducing agent and the reduced graphene oxide product by a filtering device, 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 single-layer rates.
Preferably, the 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 the steps of adding graphene oxide into a solvent to obtain a uniform graphene oxide dispersion liquid with the concentration of 1-10mg/mL, carrying out ultrasonic treatment on the dispersion liquid, wherein the ultrasonic power is 200-1000 watts, the ultrasonic time is 5-30 minutes, stirring is carried out until the dispersion liquid is uniform, the stirring 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, and the step of mixing and reacting the graphene oxide and the reducing agent in the microchannel reactor comprises:
step 1: firstly, adding the graphene oxide dispersion liquid into a first raw material tank, and keeping stirring at the stirring speed of 200-; then adding the reducing agent solution into a second raw material tank, and keeping stirring at the same speed of 200-700 revolutions per minute.
And 2, step: the temperature of the microchannel reactor is controlled to be 30-200 ℃, and the temperature is 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 a 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 react in the microchannel reactor.
Wherein the microchannel reactor is a microchannel with a circular cross section with the 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 microchannel reactor is 3-30 mL.
And step 3: and 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 washed by deionized water, ethanol and acetone and repeated for 2-4 times.
And 4, step 4: and transferring the washed reduced graphene oxide filter cake into an oven, and drying at 40-90 ℃ for 4-12 hours.
In the above examples, the reducing agent is sodium borohydride, hydrohalic acid, sodium persulfate, hydrazine hydrate, pyrrole, ethylenediamine, L-ascorbic acid, and plant extracts such as polyphenol and polyphenol compound in 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 concentration of the graphene oxide dispersion is 1-3 mg/mL.
Preferably, L-ascorbic acid is selected as a reducing agent, and the concentration range is 0.1-10 mg/mL; or hydroiodic acid as a reducing agent at a concentration of 0.1-10 wt.%.
Aiming at the problems of slow reaction, complex preparation steps, difficulty in continuous production, quality uniformity of the reduced graphene oxide product and the like in the existing graphene oxide reduction process, the invention provides efficient mixing and mass and heat transfer by utilizing a microfluidic technology, promotes species transportation in the reaction process and improves the microcosmic distribution uniformity of fluid. The method provides a high-efficiency, safe and easily-amplified reduced graphene oxide technology, can shorten the reduction time to be within 20min, realizes high-quality and uniform production of the reduced graphene oxide by utilizing the axially uniform fluid form distribution in the microchannel reactor, and realizes a continuous reduction process. In addition, the method can be used together with graphene oxide micro-fluidic control equipment, post-processing and the like to construct a graphene oxide multifunctional continuous preparation platform.
Various embodiments according to the present invention will be described in detail below.
Example 1
Graphene oxide dispersion liquid: the graphene oxide aqueous dispersion is prepared to be 1mg/mL, and then ultrasonic sound is carried out for 30 minutes at 200W.
Reducing agent: 3.6 wt.% aqueous hydriodic acid.
Micro-channel reactor: the liquid hold-up for the single microchannel reactor was 1.57 mL.
Controlling the temperature of the microchannel reactor to be 60 ℃, pumping the graphene oxide dispersion liquid and the hydriodic acid aqueous solution into the microchannel reactor group at the flow rate of 428 mu L/min respectively, enabling the corresponding residence time to be 9.2min, connecting a microchannel outlet with a suction filtration device, separating a product reduced graphene oxide filter cake, washing the product three times with deionized water, ethanol and acetone, and then drying the product in an oven at 60 ℃ for 6 hours to obtain the prepared reduced graphene oxide as shown in figure 2.
Example 2
Graphene oxide dispersion liquid: the graphene oxide aqueous dispersion is prepared to be 1mg/mL, and then ultrasonic sound is carried out for 30 minutes at 200W.
Reducing agent: 0.88mg/mL of aqueous L-ascorbic acid solution.
Micro-channel reactor: the liquid hold-up for the single microchannel reactor was 2.36 mL.
Controlling the temperature of the microchannel reactor to be 90 ℃, pumping the graphene oxide dispersion liquid and the hydriodic acid aqueous solution into a microchannel reactor group at the flow rate of 530 mu L/min respectively, wherein the corresponding residence time is 11.1min, connecting a microchannel outlet with a suction filtration device, separating a product reduced graphene oxide filter cake, washing the product three times with deionized water, ethanol and acetone, and then drying the product in a 60 ℃ oven for 6 hours to obtain the reduced graphene oxide shown in figure 3, wherein the XPS diagram of figure 3 clearly shows that the graphene oxide is effectively reduced, and the reduction can be carried out within 11.1min, and the time required by the microchannel reduction is shorter compared with the condition in a beaker at the same reducing agent and similar temperature.
Example 3
Graphene oxide dispersion liquid: the graphene oxide aqueous dispersion is prepared to be 2mg/mL, and then ultrasonic sound is carried out for 30 minutes at 200W.
Reducing agent: 1.76mg/mL of aqueous L-ascorbic acid solution.
Micro-channel reactor: the liquid hold-up for the single microchannel reactor was 1.57 mL.
Controlling the temperature of the microchannel reactor to be 90 ℃, pumping the graphene oxide dispersion liquid and the hydriodic acid aqueous solution into the microchannel reactor group at the flow rate of 485 mu L/min respectively, enabling the corresponding residence time to be 12.1min, connecting a microchannel outlet with a suction filtration device, separating a product reduced graphene oxide filter cake, washing the product three times with deionized water, ethanol and acetone, and then drying the product in an oven at the temperature of 60 ℃ for 6 hours, wherein the prepared reduced graphene oxide is shown in figure 4, and the graphene oxide is effectively reduced.
The method realizes efficient and continuous reduction of the graphene oxide, and the reduction time can be reduced to 5-20 min. The precise regulation of the oxygen content of the reduced graphene oxide can be realized by regulating reaction parameters such as reaction temperature, reducing agent concentration and the like or fluid parameters including flow rate, reaction time, micro-channel configuration and the like.
Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The utility model provides a micro-fluidic reaction system, its characterized in that includes a plurality of head tanks, microchannel reactor, filter equipment and a plurality of holding vessel, and partly head tank is used for storing oxidation graphite alkene dispersion, and another part head tank is used for storing reductant solution, the microchannel reactor is used for importing oxidation graphite alkene dispersion and reductant solution and mixes and react, filter equipment is used for separating the solvent that contains the reductant and reduces oxidation graphite alkene product, partly holding vessel is used for collecting the reduction oxidation graphite alkene filter cake that filter equipment filtered out, another part holding vessel is used for collecting the mixed solution after filter equipment filters.
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 as claimed in claim 1, wherein the channel of the microchannel reactor is a round-section microchannel with a diameter of 100-2000 μm or a rectangular microchannel with a side length of 50-2000 μm; preferably, the device comprises a plurality of microchannel reactors, and the total liquid holdup of the microchannel reactors is 3-30 mL; preferably, the liquid hold-up of a single microchannel reactor is 1.57 or 2.36 mL.
4. The microfluidic reaction system according to claim 1, wherein the graphene oxide dispersion has a concentration of 1-10mg/mL, preferably 1-3 mg/mL; preferably, the reducing agent in the reducing agent solution is at least one of sodium borohydride, hydrohalic acid, sodium persulfate, hydrazine hydrate, pyrrole, ethylenediamine, L-ascorbic acid and polyphenol compound of plant extract, further preferably, the reducing agent is L-ascorbic acid with the concentration of 0.1-10 mg/mL; further preferably, the reducing agent is hydroiodic acid at a concentration of 0.1 to 10 wt.%.
5. The microfluidic reaction system according to claim 1, further comprising an oven for drying the reduced graphene oxide filter cake.
6. A method for preparing reduced graphene oxide by using the microfluidic reaction system of claim 1, comprising:
preparing a graphene oxide dispersion liquid;
adding the graphene oxide dispersion liquid into a raw material tank, and keeping stirring, wherein preferably, the stirring speed is 200-700 rpm;
preparing a reducing agent solution;
adding the reducing agent solution into the other raw material tank and keeping stirring, wherein the stirring speed is preferably 200-700 revolutions per minute;
introducing the 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 the solvent containing the reducing agent and the reduced graphene oxide product by a filtering device, collecting and cleaning a reduced graphene oxide filter cake;
and drying the reduced graphene oxide filter cake, preferably, drying at 40-90 ℃ for 4-12 hours.
7. The method according to claim 6, wherein the step of preparing the graphene oxide dispersion liquid 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, wherein the ultrasonic power of the ultrasonic treatment is preferably 200-1000 watts; preferably, the sonication time of the sonication is 5-30 minutes; preferably, the stirring speed is 200-700 rpm; preferably, the stirring time is 0.5 to 4 hours; preferably, the concentration of the graphene oxide dispersion liquid is 1-3 mg/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.
8. The method of claim 6, wherein the step of preparing a reducing agent solution comprises:
dispersing a reducing agent into a reaction solvent to obtain a reducing agent solution; preferably, the reducing agent is at least one of sodium borohydride, hydrohalic acid, sodium persulfate, hydrazine hydrate, pyrrole, ethylenediamine, L-ascorbic acid and polyphenol compound of plant extracts, and further preferably, the reducing agent is L-ascorbic acid with the concentration of 0.1-10 mg/mL; further preferably, the reducing agent is hydroiodic acid at a concentration of 0.1 to 10 wt.%.
9. The method of claim 6, wherein the step of introducing the graphene oxide dispersion and the reducing agent solution into the microchannel reactor, and the step of mixing and reacting the graphene oxide and the reducing agent in the microchannel reactor comprises:
controlling the temperature of the microchannel reactor to be below the boiling point of the dispersion liquid, preferably controlling the temperature to be 30-200 ℃; introducing the graphene oxide dispersion liquid and the reducing agent solution into a microchannel reactor at the same flow rate, wherein the preferable feeding flow rate is 10 mu L/min-5 mL/min; preferably, the pumping pressure range of the feeding pump is 0.1-4 MPa; the graphene oxide and the reducing agent are mixed and reacted in the microchannel reactor.
10. The method of claim 6, wherein the collected reduced graphene oxide filter cake is washed with deionized water, ethanol and acetone multiple times, preferably, 2-4 times of washing the reduced graphene oxide filter cake is repeated.
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| CN114956188A (en) * | 2022-06-19 | 2022-08-30 | 安徽大学 | Method for continuously preparing manganese dioxide with specific crystal form by micro-fluidic method |
| 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 (10)
| 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 |
| US20180067000A1 (en) * | 2015-03-24 | 2018-03-08 | National University Of Singapore | A resistive microfluidic pressure sensor |
| 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 |
-
2022
- 2022-02-11 CN CN202210130006.5A patent/CN114572969B/en active Active
Patent Citations (10)
| 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 |
| US20180067000A1 (en) * | 2015-03-24 | 2018-03-08 | National University Of Singapore | A resistive microfluidic pressure sensor |
| 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 |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114956188A (en) * | 2022-06-19 | 2022-08-30 | 安徽大学 | Method for continuously preparing manganese dioxide with specific crystal form by micro-fluidic method |
| 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 |
| CN115507307B (en) * | 2022-09-12 | 2024-05-14 | 西南石油大学 | Hydrogen leakage monitoring and responding 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 |
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