A reduction system for continuously electrochemically reducing graphene oxide in a liquid flow

Abstract

The present invention provides a reduction system for continuously electrochemically reducing graphene oxide in a liquid flow, comprising a pre-reduction component and a reaction component; the pre-reduction component includes an auxiliary device; the auxiliary device includes a sealed tube body, the two ends in the length direction of the sealed tube body are sealed, one end is provided with a feed pipe, and the other end is provided with a discharge pipe; the sealed tube body is communicated with the discharge end of a feed pump through the feed pipe, the feed end of the feed pump is connected to a slurry buffer tank through a pipeline, the slurry buffer tank is also connected to the first port of a discharge three-way valve, the second port of the discharge three-way valve is communicated with a confluence chamber of the auxiliary device through the discharge pipe, the third port of the discharge three-way valve is connected to the liquid inlet main pipe of the reaction component, and the liquid discharge main pipe of the reaction component is communicated with the slurry buffer tank. This device pre-reduces graphene oxide by setting up a pre-reduction component, and then electrochemically reduces graphene oxide continuously in a liquid flow through a reaction component that is circularly connected to the pre-reduction component, thereby improving the reduction efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of graphene preparation equipment, and particularly relates to a reduction system for continuously electrochemically reducing graphene oxide in a liquid flow. Background Art

[0002] Graphene is a honeycomb hexagonal planar two-dimensional crystal formed by arranging single-layer sp 2 hybridized carbon atoms. In the two-dimensional plane, the sp 2 hybridized carbon atoms are connected to three adjacent carbon atoms through σ bonds. The remaining p electron orbitals are perpendicular to the graphene plane and form a large π bond with surrounding atoms, enabling graphene to have good electrical and thermal conductivity as well as mechanical properties. The electron mobility is as high as 200000 cm 2 / (V·s), the electrical conductivity reaches 106 S / m, the thermal conductivity can reach 5000 W / (m·K), and the strength can reach 130 GPa. These excellent properties of graphene make it have great potential application prospects in optoelectronic devices, chemical power sources (such as solar cells, lithium-ion batteries), gas sensors, antistatic and heat dissipation materials, etc. The prerequisite for graphene to have the above excellent properties is that the graphene structure is complete and of high quality, and can be produced on a large scale. However, the current mainstream graphene preparation methods still face great challenges for large-scale industrial applications.

[0003] Graphene is a honeycomb hexagonal planar two-dimensional crystal formed by arranging single-layer sp 2 hybridized carbon atoms. In the two-dimensional plane, the sp 2 hybridized carbon atoms are connected to three adjacent carbon atoms through σ bonds. The remaining p electron orbitals are perpendicular to the graphene plane and form a large π bond with surrounding atoms, enabling graphene to have good electrical and thermal conductivity as well as mechanical properties. The electron mobility is as high as 200000 cm 2 / (V·s), the electrical conductivity reaches 106 S / m, the thermal conductivity can reach 5000 W / (m·K), and the strength can reach 130 GPa. These excellent properties of graphene make it have great potential application prospects in optoelectronic devices, chemical power sources (such as solar cells, lithium-ion batteries), gas sensors, antistatic and heat dissipation materials, etc. The prerequisite for graphene to have the above excellent properties is that the graphene structure is complete and of high quality, and can be produced on a large scale. However, the current mainstream graphene preparation methods still face great challenges for large-scale industrial applications.

[0004] In the existing graphene preparation technologies, the oxidation-reduction method is the mainstream preparation method for industrial production of graphene at present, with large output and easy large-scale production. However, this method first requires obtaining graphene oxide intermediate products through chemical oxidation. There are a large number of oxygen-containing groups in the structure of graphene oxide, forming a large number of structural defects, which greatly reduces the electrical and thermal conductivity of graphene. Therefore, higher-quality graphene products can only be obtained through further reduction treatment. The existing reduction methods mainly include chemical reduction method and thermal reduction method. The chemical reduction method involves the use of strong reducing agents (such as hydrazine hydrate, sodium borohydride, potassium borohydride), and the thermal reduction method requires a high-temperature environment above 1000 °C. Both have problems such as environmental unfriendliness and high-temperature energy consumption, resulting in high production costs of graphene, which is not conducive to large-scale industrial application of graphene. At the same time, the reduction process will also cause serious environmental pollution, which is not conducive to environmental protection and the realization of green production.

[0005] The existing graphene reduction methods also adopt electrochemical reduction methods. For example, the Chinese invention patent with the publication number CN104593802B discloses an electrochemical preparation method for reducing graphene, and the Chinese invention patent with the publication number CN106676562B discloses a method for reducing and preparing graphene by electrochemical method. The above methods can prepare graphene well, save energy, and cause less pollution to the environment. However, due to the limitation that existing electrochemical reduction can only prepare graphene in small amounts through electrode modification or in the laboratory using simple components such as beakers, existing electrochemical reduction cannot produce graphene in large quantities, which is not conducive to industrial production and cannot fully achieve green production.

[0006] Secondly, in order to improve the reduction efficiency, some scholars have also proposed pre-reduction before the electrochemical reaction. For example, a method for preparing graphene proposed in the Chinese invention patent application with the publication number CN114195137A. In this method, graphene oxide solution is mixed with a reducing agent and reacted to obtain a chemically reduced graphene solution; then the chemically reduced graphene solution is put into an electrolytic cell and further reduced by an electrochemical reaction to improve the reduction degree of graphene and obtain an electrochemically reduced graphene solution. Although this method can greatly improve the reduction effect, the pre-reduction operation still uses the chemical reduction method, and the pre-reduction operation and the electrochemical reduction operation are carried out separately and require manual transfer. Therefore, this method is an intermittent operation with low production efficiency and is not conducive to large-scale industrial production.

[0007] Furthermore, in existing electrochemical reactions, the electrodes in the electrolytic cell are fixed and the electrolyte is also in a static state. As we know, the more intense the perturbation of the reactants, the more complete the reaction, and the better the reaction effect. On the contrary, the less perturbation of the reactants, the worse the reaction effect. Similarly, the same is true for the electrochemical reaction of graphene in the electrolytic cell. Therefore, the existing structures for electrochemical reactions cannot meet the requirements for highly efficient production of high-quality graphene. Secondly, when the electrolyte flows or is perturbed, the graphene in the electrolyte can react well with the electrodes. However, when the graphene flows to the anode, it is prone to an oxidation reaction with the oxygen generated at the anode, which to a certain extent affects the reduction efficiency and reduction effect of graphene. At the same time, the oxygen generated at the anode is easily mixed with the hydrogen generated at the cathode. When a large amount of oxygen and hydrogen are mixed, it is very easy to cause an explosion accident. This is also one of the reasons why large-scale production of reduced graphene by electrochemical reaction cannot be used at present. Moreover, since the electrodes are exposed in the electrolytic cell, the graphene in the electrolyte has a strong conductive effect and is prone to connect the anode and the cathode in the electrolytic cell, resulting in a short circuit between the anode and the cathode and preventing the electrochemical reaction from proceeding.

[0008] For the above reasons, the current devices for electrochemical reactions cannot meet the requirements for large-scale and industrial production of reduced graphene by electrochemical methods. Moreover, the production efficiency and production effect need to be improved. At the same time, intermittent operation is required, continuous reaction is not possible, and the amount of manual work is large.

[0009] Aiming at the deficiencies of the existing technology, the present invention provides a reduction system for continuous liquid-flow electrochemical reduction of graphene oxide. It pre-reduces the graphene oxide before the electrochemical reaction by setting a pre-reduction component, and then conducts continuous liquid-flow electrochemical reduction of graphene oxide through a reaction component that is cyclically connected to the pre-reduction component, improving the reduction efficiency and obtaining high-quality reduced graphene. Moreover, there is no need for manual transfer, and continuous production reaction can be carried out, thus facilitating large-scale industrial production of reduced graphene, with high production efficiency and less pollution, meeting the requirements of green production. Summary of the Invention

[0010] To achieve the above object, the technical solution adopted by the present invention is:

[0011] A reduction system for continuously electrochemically reducing graphene oxide in a liquid flow, comprising a pre-reduction component and a reaction component; the pre-reduction component includes an auxiliary device, a feed pump, a slurry buffer tank, a discharge three-way valve, a sulfite solution storage tank, a sulfite solution feeding pump, and a total control unit; the auxiliary device includes an encapsulating tube body, both ends of the encapsulating tube body in the length direction are sealed, one end is provided with a feed pipe, and the other end is provided with a discharge pipe; the interior of the encapsulating tube body is sequentially partitioned along the length direction into a diversion chamber, a reaction chamber, and a confluence chamber; the diversion chamber is communicated with the feed pipe, the confluence chamber is communicated with the discharge pipe, a UV lamp group and a high-transparency fluid tube are arranged in the reaction chamber, the UV lamp group and the high-transparency fluid tube are arranged at intervals, the high-transparency fluid tube is made of a light-transmitting material, one end of the high-transparency fluid tube is communicated with the diversion chamber and the other end is communicated with the confluence chamber; the diversion chamber of the auxiliary device is communicated with the discharge end of the feed pump through the feed pipe, the feed end of the feed pump is connected to the slurry buffer tank through a pipeline, the slurry buffer tank is also connected to the first port of the discharge three-way valve, the second port of the discharge three-way valve is communicated with the confluence chamber of the auxiliary device through the discharge pipe, the third port of the discharge three-way valve is connected to the liquid inlet main pipe of the reaction component, and the liquid discharge main pipe of the reaction component is communicated with the slurry buffer tank; the sulfite solution storage tank is connected to the feed pipe of the auxiliary device through the sulfite solution feeding pump; the sulfite solution feeding pump, the feed pump, the UV lamp group, and the cathode guide rod of the reaction component are all electrically connected to the total control unit.

[0012] Preferably, the reaction component includes at least one tubular reduction device. When the number of tubular reduction devices is greater than one, all the tubular reduction devices are connected in series or in parallel. When the number of tubular reduction devices is greater than two, the connection relationship of all the tubular reduction devices further includes a coexistence of series and parallel connections.

[0013] Each tubular reduction device includes a tubular cathode and a tubular anode. An anode-cathode isolation filter cartridge is disposed at an interval between the tubular cathode and the tubular anode. The anode-cathode isolation filter cartridge and the tubular cathode are sequentially sleeved outside the tubular anode. A lower flange head is hermetically fixed to the lower end of the tubular cathode. An inlet liquid shunt chamber is provided at one end of the lower flange head facing away from the tubular cathode. An inlet liquid main pipe and an inlet liquid branch pipe are provided on the inlet liquid shunt chamber. One end of the inlet liquid main pipe is located outside the inlet liquid shunt chamber, and the other end is located inside the inlet liquid shunt chamber and communicates with the inlet liquid shunt chamber. One end of the inlet liquid branch pipe is located inside the inlet liquid shunt chamber and communicates with the inlet liquid shunt chamber, and the other end penetrates through the lower flange head and extends between the tubular cathode and the anode-cathode isolation filter cartridge. An upper flange head is hermetically fixed to the upper end of the tubular cathode. An outlet liquid confluence chamber is provided at one end of the upper flange head facing away from the tubular cathode. A drain liquid branch pipe, a drain liquid main pipe, a cathode exhaust pipe, and an anode exhaust pipe are provided on the outlet liquid confluence chamber. One end of the drain liquid branch pipe is located inside the outlet liquid confluence chamber and communicates with the outlet liquid confluence chamber, and the other end penetrates through the upper flange head and extends between the tubular cathode and the anode-cathode isolation filter cartridge. One ends of both the drain liquid main pipe and the cathode exhaust pipe are located outside the outlet liquid confluence chamber, and the other ends are located inside the outlet liquid confluence chamber and communicate with the outlet liquid confluence chamber. Among them, inside the outlet liquid confluence chamber, the distance between the end of the drain liquid branch pipe and the upper flange head is greater than the distance between the end of the drain liquid main pipe and the upper flange head, but less than the distance between the end of the cathode exhaust pipe and the upper flange head. One end of the anode exhaust pipe is outside the outlet liquid confluence chamber, and the other end penetrates through the upper flange head from the outlet liquid confluence chamber and extends inside the anode-cathode isolation filter cartridge.

[0014] A filter layer is provided on the side wall of the anode-cathode isolation filter cartridge facing the tubular cathode. The lower end of the anode-cathode isolation filter cartridge is fixedly connected to the lower flange head, and the upper end is fixedly connected to the upper flange head.

[0015] The lower end of the tubular anode is fixedly connected to the lower flange head, and the upper end is disposed at an interval from the upper flange head. The upper end of the tubular anode is located below the end of the anode exhaust pipe located inside the anode-cathode isolation filter cartridge. An anode guide rod is provided at the upper end of the tubular anode. One end of the anode guide rod is connected to the tubular anode, and the other end penetrates through the outlet liquid confluence chamber and extends outside the outlet liquid confluence chamber. The anode guide rod is electrically connected to the total control unit.

[0016] Preferably, the tubular cathode is a metal part, and an insulating glue layer is provided on its outer wall. Both ends of the tubular cathode are of flange plate structure. The upper flange head and the lower flange head are both flange plate structures made of insulating materials. The tubular cathode is fixedly connected to the upper flange head and the lower flange head by flange connection. When fixedly connecting, the flange plate structures at both ends of the tubular cathode are fixedly connected to the flange head at its corresponding end by fixing parts. Among them, the fixing parts include fixing caps and connecting rods. The connecting rods are inserted into the flange plate structure of the tubular cathode and the flange head at its corresponding end at the same time. The connecting rods are metal parts, and the fixing caps are insulating parts, which are installed at one end of the connecting rods; the connecting rods are cathode guide rods, which are electrically connected to the master control unit.

[0017] Preferably, the anode-cathode isolation filter cartridge includes three layers; among them, the outer layer is the layer facing the tubular cathode, and this outer layer is the filter layer. The filter layer is a filter membrane, and the filter membrane is a polypropylene fiber membrane, a polytetrafluoroethylene membrane, a nylon membrane, a plastic woven filter cloth or a non-woven fabric; the middle layer is a filter screen structure, and the pore diameter of the filter screen structure is larger than that of the filter membrane; the inner layer is a reticulated rigid circular tube structure, and the pore diameter of the rigid circular tube structure is larger than that of the filter screen structure; the rigid circular tube structure and the filter screen structure are made of plastic, ceramic or metal materials.

[0018] Preferably, an insulating glue layer is provided on the outer wall of the tubular cathode, and the inner wall is a non-smooth metal surface.

[0019] Preferably, metal oxide coatings are provided on the outer walls of the anode guide rod and the tubular anode, and the metal oxide coatings are one or more mixtures of lead-based, tin-based, ruthenium-based, iridium-based, tantalum-based materials.

[0020] Preferably, the encapsulation tube body is of cylindrical structure and is made of light-tight materials; a reflective coating is provided on the inner wall of the encapsulation tube body.

[0021] Preferably, a plurality of high-transparency fluid tubes are provided, and the ultraviolet lamp group has a plurality of ultraviolet lamp strips, and the plurality of ultraviolet lamp strips and all the high-transparency fluid tubes are arranged alternately.

[0022] Preferably, the second port of the discharge three-way valve is also communicated with the feed end of the feed pump through a pipeline, and a pipeline stop valve is installed on the pipeline.

[0023] Preferably, the pre-reduction assembly further includes a pH probe, a pH buffer solution storage tank and a buffer solution feeding pump; the pH probe is installed on the confluence chamber of the auxiliary device, and the pH buffer solution storage tank is connected to the feed pipe of the auxiliary device through the buffer solution feeding pump; both the buffer solution feeding pump and the pH probe are electrically connected to the master control unit.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. In the reduction system of the present invention, the designed pre-reduction component can perform preliminary reduction treatment on graphene oxide in the electrolyte, and the designed reaction component can perform electrochemical reduction reaction on the pre-reduced graphene. Moreover, the reaction component and the pre-reduction component form a circuit, and the electrolyte can carry graphene for cyclic pre-reduction and electrochemical reduction reactions without manual transfer, reducing the labor operation cost. At the same time, due to the cyclic design, the electrolyte flows continuously in the reaction component with a certain disturbance, making the reaction of graphene more sufficient. That is, the reduction system of the present invention can be used for continuous liquid flow electrochemical reduction of graphene oxide, improving the reduction effect and reduction efficiency of graphene, and is suitable for large-scale industrial production of graphene. It should be emphasized that the method for continuous liquid flow electrochemical reduction of graphene served by the reduction system of the present invention is a pioneer. Compared with the existing electrochemical reduction reactions, it can enhance the reduction effect of graphene oxide and significantly improve the reduction productivity. It does not require harsh production conditions such as high temperature and high vacuum, has low production requirements, is environmentally friendly, energy-saving and low-cost, and is worthy of promotion.

[0026] 2. The auxiliary device in the pre-reduction component of the present invention introduces the electrolyte into the shunt chamber of the encapsulated tube body through the feed pipe. The electrolyte buffers and decelerates in the shunt chamber, then enters the highly transparent fluid tube located in the reaction chamber, flows from the highly transparent fluid tube to the confluence chamber, and then flows out from the discharge pipe connected to the confluence chamber. Among them, during the flow of the electrolyte in the highly transparent fluid tube, it can be irradiated by the ultraviolet rays emitted by the ultraviolet lamp group. The sulfite radical in the electrolyte is activated by the ultraviolet rays and can generate strongly reducing free radicals. The generated strongly reducing free radicals can pre-reduce the graphene oxide in the electrolyte, thereby improving the reduction efficiency and reduction effect of subsequent electrochemical reduction of graphene oxide, and then obtaining high-quality reduced graphene.

[0027] 3. The tubular reduction device of the reaction component of the present invention is set in a tubular structure, and the anode and the cathode are separated by the anode-cathode isolation filter cartridge. On the one hand, it avoids the influence of the oxidizing molecules or ions generated at the anode during the electrolysis process on the reduction of graphene. On the other hand, the tubular structure cooperates with the uneven frosted structure on the inner wall of the tubular cathode, which can make the graphene solution tumble and flow on the cathode surface, so that the graphene in the electrolyte has a greater chance of contacting the cathode and is also more likely to be exposed to the reducing solution environment generated during the electrolysis of the cathode. Overall, it increases the contact chance with hydrogen free radicals and hydrated electrons, and thus has a better reduction effect and higher reduction efficiency.

[0028] 4. The reaction component of the present invention is provided with a tubular structure and feeds from the bottom. When it enters the electrode reduction area, a small amount of bubbles generated by the electrode can further enhance the disturbance of graphene on the electrode surface, enabling graphene to have a longer residence time within the cathode tube stroke, greatly increasing the contact probability between graphene and the electrode, and improving the reduction efficiency. In addition, the bubbles generated by the reaction can form a good push on the electrolyte. On the one hand, it avoids the agglomeration of graphene, and on the other hand, it directly prevents the material from depositing at the bottom of the tubular device, improving the stability and consistency of the electrochemical reduction batch.

[0029] 5. The number of tubular reduction devices in the reaction component of the present invention can be selected according to actual production needs, so as to meet different production requirements, prepare high-quality graphene, and have relatively high reduction efficiency and production efficiency. At the same time, the reduction degree of graphene oxide can be regulated by simply connecting the tubular reduction devices in series or parallel in the reaction component to prepare reduced graphene of different qualities. Therefore, using it to prepare graphene has low production cost, little pollution, and high quality, and is suitable for large-scale industrial production of graphene. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a schematic structural diagram of the present invention.

[0031] Figure 2 is a schematic structural diagram of the auxiliary device of the present invention;

[0032] Figure 3 is a partial sectional view of the auxiliary device of the present invention;

[0033] Figure 4 is a schematic structural diagram of the tubular reduction device of the present invention;

[0034] Figure 5 is Figure 4 a schematic structural diagram of the upper middle part in, in the figure, with a partial section;

[0035] Figure 6 is Figure 4 the internal view of.

[0036] MAIN ELEMENT SYMBOL DESCRIPTION

[0037] In the figure: auxiliary device 1, encapsulation tube body 1.1, shunt chamber 1.2, reaction chamber 1.3, confluence chamber 1.4, feed pipe 1.5, discharge pipe 1.6, ultraviolet lamp group 1.7, high-transparency fluid pipe 1.8, discharge three-way valve 2, slurry buffer tank 3, feeding pump 4, sulfite solution feeding pump 5, sulfite solution storage tank 6, pH buffer solution storage tank 7, buffer solution feeding pump 8, pH probe 9, pipeline stop valve 10, tubular reduction device 20, tubular cathode 20.1, flange plate structure 20.1.1, cathode-anode isolation filter cartridge 20.2, tubular anode 20.3, liquid inlet shunt chamber 20.4, liquid inlet main pipe 20.5, liquid inlet branch pipe 20.6, liquid outlet confluence chamber 20.7, liquid discharge branch pipe 20.8, liquid discharge main pipe 20.9, cathode exhaust pipe 20.10, anode exhaust pipe 20.11, gas accumulation chamber 20.12, anode guide rod 20.13, lower flange head 20.14, upper flange head 20.15, fixing part 20.16, connecting rod 20.16.1, fixing cap 20.16.2, temperature control jacket 20.17, cathode temperature control fluid inlet pipe 20.18, cathode temperature control fluid outlet pipe 20.19, temperature control coiled pipe 20.20, vacuum defoaming device 30, total control unit 40, total discharge pipe 50, total feed pipe 60.

[0038] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. Specific embodiments

[0039] Please refer to Figures 1-6, in a preferred embodiment of the present invention, a reduction system for continuously electrochemically reducing graphene oxide in a liquid flow includes a pre-reduction component and a reaction component; the pre-reduction component includes an auxiliary device 1, a feed pump 4, a slurry buffer tank 3, a discharge three-way valve 2, a sulfite solution storage tank 6, a sulfite solution feeding pump 5, and a total control unit 40; the auxiliary device 1 includes an encapsulating tube body 1.1, both ends of the encapsulating tube body 1.1 in the length direction are sealed, one end is equipped with a feed pipe 1.5, and the other end is equipped with a discharge pipe 1.6; inside the encapsulating tube body 1.1, a diversion chamber 1.2, a reaction chamber 1.3, and a confluence chamber 1.4 are sequentially separated and arranged along the length direction; the diversion chamber 1.2 is communicated with the feed pipe 1.5, the confluence chamber 1.4 is communicated with the discharge pipe 1.6, an ultraviolet lamp group 1.7 and a highly transparent fluid pipe 1.8 are arranged in the reaction chamber 1.3, the ultraviolet lamp group 1.7 and the highly transparent fluid pipe 1.8 are arranged at intervals, the highly transparent fluid pipe 1.8 is made of a light-transmitting material, one end of the highly transparent fluid pipe 1.8 is communicated with the diversion chamber 1.2 and the other end is communicated with the confluence chamber 1.4; the diversion chamber 1.2 of the auxiliary device 1 is communicated with the discharge end of the feed pump 4 through the feed pipe 1.5, the feed end of the feed pump 4 is connected to the slurry buffer tank 3 through a pipeline, the slurry buffer tank 3 is also connected to the first port of the discharge three-way valve 2, the second port of the discharge three-way valve 2 is communicated with the confluence chamber 1.4 of the auxiliary device 1 through the discharge pipe 1.6, the third port of the discharge three-way valve 2 is connected to the liquid inlet main pipe 20.5 of the reaction component, and the liquid discharge main pipe 20.9 of the reaction component is communicated with the slurry buffer tank 3; the sulfite solution storage tank 6 is connected to the feed pipe 1.5 of the auxiliary device 1 through the sulfite solution feeding pump 5; the sulfite solution feeding pump 5, the feed pump 4, the ultraviolet lamp group 1.7, and the cathode guide rod of the reaction component are all electrically connected to the total control unit 40.

[0040] In the present invention, by setting a pre-reduction component to pre-reduce the electrolyte and the contained graphene oxide before the electrochemical reduction reaction, and then enter the reaction component for the electrochemical reduction reaction, thereby improving the reduction effect and reduction quality of graphene.

[0041] Specifically, in the reduction component of the present invention, the electrolyte to be processed and the graphene oxide to be reduced are placed through the slurry buffer tank 3, and the sulfite solution is placed through the sulfite solution storage tank 6. The sulfite solution is one or a mixture of sodium sulfite, ammonium sulfite, potassium sulfite, and lithium sulfite. The auxiliary device 1 is used to pre-treat the fluid flowing through it, and the fluid includes the slurry composed of the electrolyte and graphene oxide, and the sulfite solution. Through the setting of multiple feeding pumps and the discharge three-way valve 2, the slurry can be circulated for pre-treatment, and after the treatment is completed, it is diverted to the reaction component for electrochemical reduction reaction, thereby assisting the reaction component to prepare high-quality reduced graphene, and improving the batch consistency and stability of the electrochemically reduced graphene.

[0042] Please refer to Figures 2-3 , in the reduction component of the present invention, the diversion chamber 1.2 and the confluence chamber 1.4 in the auxiliary device 1 are connected through the high-transparency fluid pipe 1.8. The electrolyte is pumped into the diversion chamber 1.2 through the feed pipe 1.5 under the action of the feed pump 4. After collecting and buffering in the diversion chamber 1.2, it then flows through the high-transparency fluid pipe 1.8 to the confluence chamber 1.4, and then flows out from the discharge pipe 1.6 connected to the confluence chamber 1.4. During this flowing process, the ultraviolet lamp group 1.7 in the reaction chamber 1.3 emits ultraviolet rays, and the ultraviolet rays penetrate the tube wall of the high-transparency fluid pipe 1.8 and irradiate the fluid such as the electrolyte in the tube. The sulfite radicals contained in the fluid are activated under the ultraviolet irradiation, generating strongly reducing free radicals. The generated strongly reducing free radicals react with the graphene oxide in the electrolyte, and the graphene oxide is pre-reduced. In this way, when the pre-treated electrolyte enters the subsequent electrochemical reaction component through the discharge three-way valve 2, it can enter the reaction component together with the activated sulfite radicals, the generated strongly reducing free radicals, etc. When an electrochemical reaction occurs in the reaction component, the strongly reducing free radicals can assist the graphene oxide to be rapidly reduced at the cathode of the reaction component, thereby improving the actual reduction efficiency, and improving the batch consistency and stability of the electrochemically reduced graphene.

[0043] Furthermore, for better pre-reduction treatment of the electrolyte, the pre-reduction assembly further includes a pH probe 9, a pH buffer solution storage tank 7, and a buffer solution feeding pump 8; the pH probe 9 is installed on the confluence chamber 1.4 of the auxiliary device 1, and the pH buffer solution storage tank 7 is connected to the feed pipe 1.5 of the auxiliary device 1 through the buffer solution feeding pump 8; both the buffer solution feeding pump 8 and the pH probe 9 are electrically connected to the master control unit 40. The buffer solution is placed in the pH buffer solution storage tank 7, and the buffer solution can maintain the pH of the fluid in the auxiliary device 1 at 7-10. Specifically, the buffer solution is a sodium carbonate / sodium bicarbonate buffer solution. After being irradiated by ultraviolet light, sulfite radicals are activated by ultraviolet light to generate more reducing free radicals for pre-reducing graphene. After the pretreatment, it will enter the reaction assembly together with the electrolyte, pre-treated graphene, and sulfite radicals. After flowing into the reaction assembly, carbonate and bicarbonate will cooperate with sulfite radicals to remove the free oxygen radicals in the reaction assembly together, so that the reduced graphene oxide after cathode reduction is not easily interfered by free oxygen radicals, thereby further improving the reduction effect. In the present invention, the pH value of the fluid in the auxiliary device 1 is monitored by the pH probe 9 provided in the confluence chamber 1.4, and the master control unit controls the buffer solution feeding pump 8 to pump the buffer solution into the auxiliary device 1 according to the monitoring situation of the pH probe 9, so as to maintain the pH value of the fluid flowing through the auxiliary device 1 within the required range value.

[0044] In this embodiment, in order to improve the irradiation effect of the ultraviolet lamp group 1.7, the encapsulating tube body 1.1 is preferably a cylindrical structure, which is made of light-impermeable material, and a reflective coating is provided on the inner wall of the encapsulating tube body 1.1. Further, a plurality of high-transparency fluid tubes 1.8 are provided, the ultraviolet lamp group 1.7 has a plurality of ultraviolet lamp strips, and the plurality of ultraviolet lamp strips and all the high-transparency fluid tubes 1.8 are arranged in an alternating manner to better achieve shunt flow and ensure that all the high-transparency fluid tubes 1.8 can be irradiated by ultraviolet light. The ultraviolet lamp group 1.7 has a lamp group controller, and the on / off and illumination power of each ultraviolet lamp strip are controlled by the lamp group controller and do not interfere with each other, that is, each ultraviolet lamp strip is independently controlled and does not affect each other. Further, the ultraviolet rays emitted by the ultraviolet lamp group 1.7 are one or more of the UVA, UVB, UVC, and UVD bands.

[0045] In another embodiment of the present invention, the highly transparent fluid tube and the ultraviolet lamp group of the auxiliary device may also be arranged as follows: the highly transparent fluid tube is spaced from the encapsulating tube body 1.1, a flow chamber is formed between the outer wall of the highly transparent fluid tube and the inner wall of the encapsulating tube body 1.1, and the ultraviolet lamp group is located inside the highly transparent fluid tube; a diversion hole is provided on the partition between the diversion chamber 1.2 and the reaction chamber 1.3, and the diversion hole communicates the diversion chamber 1.2 with the flow chamber; a confluence hole is provided on the partition between the confluence chamber 1.4 and the reaction chamber 1.3, and the confluence hole communicates the confluence chamber 1.4 with the flow chamber.

[0046] That is, in this embodiment, the ultraviolet lamp group is located inside the highly transparent fluid tube, and the electrolyte flows in the flow chamber between the highly transparent fluid tube and the encapsulating tube body 1, which is equivalent to the electrolyte surrounding the periphery of the ultraviolet lamp group. In this way, the ultraviolet light emitted by the ultraviolet lamp group can irradiate the electrolyte through the tube wall of the highly transparent fluid tube, and this transmission method can comprehensively cover the electrolyte in the flow chamber, with a good irradiation effect, and there is no need to set multiple ultraviolet lamp groups, or in the case of setting a small number of ultraviolet lamps, the irradiation requirement can be met. Preferably, a plurality of diversion holes and confluence holes are provided, and all the diversion holes and confluence holes are arranged around the outside of the highly transparent fluid tube, which is convenient for the electrolyte to flow from the diversion chamber 1.2 to the flow chamber and flow out through the confluence chamber 1.4.

[0047] Furthermore, in the pre-reduction assembly of the present invention, among the auxiliary device 1, the feeding pump 4, the slurry buffer tank 3, the discharge three-way valve 2, the pH buffer solution storage tank 7, the buffer solution feeding pump 8, the sulfite solution storage tank 6, and the sulfite solution feeding pump 5, the two connected structures are connected by pipelines, and a pipeline stop valve 10 is installed on each pipeline to control the on-off of each pipeline. The second port of the discharge three-way valve 2 is also communicated with the feeding end of the feeding pump 4 through a pipeline, and a pipeline stop valve 10 is installed on the pipeline. That is, the flow coming out of the discharge pipe 1.6 of the auxiliary device 1 can flow to the liquid flow continuous electro-chemical reaction assembly through the third port of the discharge three-way valve 2, or can be divided into two paths through the first port of the discharge three-way valve 2. One path is to return to the slurry buffer tank 3, and then be pumped from the slurry buffer tank 3 into the diversion chamber 1.2 of the auxiliary device 1 for re-treatment, and the other path is directly pumped into the diversion chamber 1.2 of the auxiliary device 1 by the feeding pump 4 for re-treatment without flowing back to the slurry buffer tank. The specific flow mode is selected according to the actual operation and pretreatment conditions.

[0048] Based on the above analysis, it can be known that the pre-reduction component of the present invention can pre-reduce graphene oxide in the electrolyte, which can greatly improve the effect of subsequent electrochemical reduction, thereby preparing high-quality reduced graphene with high reduction efficiency. In addition, the sulfite used in the pre-reduction component during pre-reduction is a common by-product inorganic salt in industrial tail gas treatment, with low price and wide source. Therefore, the cost of reduction production is low and the green environmental protection effect is good.

[0049] In the present invention, the reaction component is used for electrochemically reducing graphene oxide, which is an electrochemical reaction with continuous flow of the electrolyte, can increase the disturbance of the electrolyte and improve the reduction effect. The reaction component includes at least one tubular reduction device 20. When the number of the tubular reduction devices 20 is greater than one, all the tubular reduction devices 20 are connected in series or in parallel. When the number of the tubular reduction devices 20 is greater than two, the connection relationship of all the tubular reduction devices 20 also includes a coexistence mode of series and parallel connection. In this way, in actual application, the number of the tubular reduction devices 20 can be selected according to the production needs, so as to improve the reduction effect and reduction efficiency.

[0050] Please refer to Figures 4-6 , each tubular reduction device 20 includes a tubular cathode 20.1 and a tubular anode 20.3. An anode-cathode isolation filter cartridge 20.2 is arranged at intervals between the tubular cathode 20.1 and the tubular anode 20.3. The anode-cathode isolation filter cartridge 20.2 and the tubular cathode 20.1 are sleeved on the outer side of the tubular anode 20.3 in sequence.

[0051] A lower flange head 20.14 is hermetically fixed to the lower end of the tubular cathode 20.1. An inlet liquid shunt chamber 20.4 is provided at one end of the lower flange head 20.14 facing away from the tubular cathode 20.1. An inlet liquid main pipe 20.5 and inlet liquid branch pipes 20.6 are provided on the inlet liquid shunt chamber 20.4. One end of the inlet liquid main pipe 20.5 is located outside the inlet liquid shunt chamber 20.4, and the other end is located inside the inlet liquid shunt chamber 20.4 and communicates with the inlet liquid shunt chamber 20.4. One end of the inlet liquid branch pipe 20.6 is located inside the inlet liquid shunt chamber 20.4 and communicates with the inlet liquid shunt chamber 20.4, and the other end penetrates through the lower flange head 20.14 and extends between the tubular cathode 20.1 and the cathode-anode isolation filter cartridge 20.2. An upper flange head 20.15 is hermetically fixed to the upper end of the tubular cathode 20.1. An outlet liquid confluence chamber 20.7 is provided at one end of the upper flange head 20.15 facing away from the tubular cathode 20.1. A liquid discharge branch pipe 20.8, a liquid discharge main pipe 20.9, a cathode exhaust pipe 20.10, and an anode exhaust pipe 20.11 are provided on the outlet liquid confluence chamber 20.7. One end of the liquid discharge branch pipe 20.8 is located inside the outlet liquid confluence chamber 20.7 and communicates with the outlet liquid confluence chamber 20.7, and the other end penetrates through the upper flange head 20.15 and extends between the tubular cathode 20.1 and the cathode-anode isolation filter cartridge 20.2. One ends of both the liquid discharge main pipe 20.9 and the cathode exhaust pipe 20.10 are located outside the outlet liquid confluence chamber 20.7, and the other ends are located inside the outlet liquid confluence chamber 20.7 and communicate with the outlet liquid confluence chamber 20.7. Among them, inside the outlet liquid confluence chamber 20.7, the distance between the end of the liquid discharge branch pipe 20.8 and the upper flange head 20.15 is greater than the distance between the end of the liquid discharge main pipe 20.9 and the upper flange head 20.15, but less than the distance between the end of the cathode exhaust pipe 20.10 and the upper flange head 20.15. One end of the anode exhaust pipe 20.11 is outside the outlet liquid confluence chamber 20.7, and the other end penetrates through the upper flange head 20.15 from the outlet liquid confluence chamber 20.7 and extends to the inside of the cathode-anode isolation filter cartridge 20.2.

[0052] A filter layer is provided on the side wall of the cathode-anode isolation filter cartridge 20.2 facing the tubular cathode 20.1. The lower end of the cathode-anode isolation filter cartridge 20.2 is fixedly connected to the lower flange head 20.14, and the upper end is fixedly connected to the upper flange head 20.15.

[0053] The lower end of the tubular anode 20.3 is fixedly connected to the lower flange head 20.14, and the upper end is arranged at an interval from the upper flange head 20.15. Moreover, the upper end of the tubular anode 20.3 is located below the end of the anode exhaust pipe 20.11 inside the anode-cathode isolation filter cartridge 20.2; an anode guide rod 20.13 is arranged at the upper end of the tubular anode 20.3. One end of the anode guide rod 20.13 is connected to the tubular anode 20.3, and the other end penetrates through the liquid outlet manifold chamber 20.7 and extends to the outside of the liquid outlet manifold chamber 20.7.

[0054] In the above tubular design, the present invention fixedly connects the tubular cathode 20.1, the tubular anode 20.3, and the cathode-anode isolation filter cartridge 20.2 for separating the tubular cathode 20.1 and the tubular anode 20.3 through the lower flange head 20.14 and the upper flange head 20.15, thereby forming a reaction area for the electrochemical reaction. The electrolyte for the electrochemical reaction flows from bottom to top. Specifically, it enters the liquid inlet shunt chamber 20.4 below the lower flange head 20.14 from the liquid inlet main pipe 20.5, is shunted after decelerating in the liquid inlet shunt chamber 20.4, and the electrolyte enters the reaction cavity between the tubular cathode 20.1 and the cathode-anode isolation filter cartridge 20.2 from the liquid inlet branch pipe 20.6. The electrolyte reacts with the tubular cathode 20.1 in this reaction cavity, and the reducing substances generated by the reaction react with the graphene oxide in the electrolyte, thereby reducing the graphene oxide. The reacted electrolyte flows to the upper flange head 20.15 under the push of the liquid flow, and flows into the liquid outlet confluence chamber 20.7 through the liquid discharge branch pipe 20.8 on the upper flange head 20.15, and then is discharged from the liquid discharge main pipe 20.9 on the liquid outlet confluence chamber 20.7. At the same time, the reducing gas generated during the electrolytic reaction of the tubular cathode 20.1 is in the form of foam, which will flow into the liquid outlet confluence chamber 20.7 together with the electrolyte. During the process of flowing to the liquid outlet confluence chamber 20.7, the reducing gas in the form of bubbles will disturb the electrolyte, thereby making the graphene in the electrolyte be disturbed on the electrode surface, enhancing the contact probability between the graphene and the electrode, and thus improving the reduction efficiency; when the reducing gas in the form of foam flows to the liquid outlet confluence chamber 20.7, since the liquid discharge branch pipe 20.8 is higher than the liquid discharge main pipe 20.9, the foam of the reducing gas will be exposed above the liquid discharge main pipe 20.9 and gather into the reducing gas in the gaseous form. And because the cathode exhaust pipe 20.10 is higher than the liquid discharge branch pipe 20.8, the reducing gas in the gaseous form gathers above the electrolyte in the liquid outlet confluence chamber 20.7 and is discharged from the cathode exhaust pipe 20.10, that is, the gas-liquid separation and the evacuation treatment after separation are realized; in the reaction chamber 1.3, due to the setting of the filter layer on the outer wall of the cathode-anode isolation filter cartridge 20.2, the electrolyte and graphene oxide entering the reaction chamber 1.3 are isolated in the reaction cavity between the tubular cathode 20.1 and the cathode-anode isolation filter cartridge 20.2, and only a small amount of electrolyte penetrates through the filter layer and the cathode-anode isolation filter cartridge 20.2 and enters the reaction cavity between the tubular anode 20.3 and the cathode-anode isolation filter cartridge 20.2. The electrolyte in this reaction cavity contacts the tubular anode 20.3 and reacts with the anode 20.3 through electrolysis. The anode 20.3 gas generated by the reaction gathers in the gas aggregation chamber 20.12 between the upper end of the tubular anode 20.3 and the upper flange head 20.15, and then is discharged through the anode exhaust pipe 20.11. In addition, due to the setting of the filter layer, the anode 20.3 gas generated by the reaction is isolated by the filter layer and cannot flow into the reaction cavity between the tubular cathode 20.1 and the cathode-anode isolation filter cartridge 20.2. At the same time, the reduced graphene also cannot contact the tubular anode 20.3, thus avoiding the anode 20.The reaction of the gas with the reduced graphene also avoids the reaction between the reduced graphene and the tubular anode 20.3, improving the reduction efficiency and effect of the graphene.

[0055] Based on the above, in the present invention, through the setting of the cathode and anode isolation filter cartridge 20.2 and the filter layer thereon, the reaction between the reduced graphene and the tubular anode 20.3 and the anode 20.3 gas is isolated, and the graphene reacts only between the tubular cathode 20.1 and the cathode and anode isolation filter cartridge 20.2, thereby improving the reduction effect and reduction efficiency.

[0056] In this embodiment, in order to enable the graphene to react better with the tubular cathode 20.1 when flowing between the tubular cathode 20.1 and the cathode and anode isolation filter cartridge 20.2, the inner wall of the tubular cathode 20.1 is a non-smooth metal surface, so as to help increase the disturbance of the fluid on the cathode surface through the rough and undulating structure on the cathode surface, improve the current utilization efficiency and the effect of electrochemical reduction. Specifically, the inner wall of the tubular cathode 20.1 can be structures such as frosted, undulating, knurled, electrolytic pore-forming, etc., with a rough and uneven surface, and the material is one of nickel and its alloys, steel, copper and its alloys, lead and its alloys, titanium and its alloys. Preferably, the tubular cathode 20.1 is a metal part, and an insulating glue layer is provided on its outer wall. Both ends of the tubular cathode 20.1 are flange plate structures 20.1.1. The upper flange head 20.15 and the lower flange head 20.14 are both flange plate structures made of insulating materials, and the material can be one or a combination of plastics or ceramics. The tubular cathode 20.1 is fixedly connected to the upper flange head 20.15 and the lower flange head 20.14 by flange connection. When fixedly connected, the flange plate structures 20.1.1 at both ends of the tubular cathode 20.1 are fixedly connected to the flange head at its corresponding end through fixing parts 20.16. Among them, the fixing part 20.16 includes a fixing cap 20.16.2 and a connecting rod 20.16.1. The connecting rod 20.16.1 simultaneously inserts into the flange plate structure 20.1.1 of the tubular cathode 20.1 and the flange head at its corresponding end. The connecting rod 20.16.1 is a metal part, and the fixing cap 20.16.2 is an insulating part, which is installed at one end of the connecting rod 20.16.1; the connecting rod 20.16.1 is a cathode guide rod, which is electrically connected to the total control unit 40; that is, the electrical connection between the tubular cathode 20.1 and the power supply is realized by winding a wire around the rod body of the connecting rod 20.16.1 between the fixing cap 20.16.2 and the flange part, thereby realizing the electrochemical reaction. Further, a plurality of fixing parts 20.16 are evenly distributed on the flange plate structure 20.1.1, and the power required for production needs is met by wiring different fixing parts 20.16, and wires can be connected to both the upper and lower ends, so that the current distribution on the tubular cathode 20.1 is more balanced and the effect is better.

[0057] Furthermore, in order to facilitate the shunt of the electrolyte into the liquid inlet shunt chamber 20.4, a plurality of liquid inlet branch pipes 20.6 are provided, and all the liquid inlet branch pipes 20.6 are arranged around the circumferential direction of the anode-cathode isolation filter cartridge 20.2. Similarly, in order to facilitate the confluence of the electrolyte after the reaction into the liquid outlet confluence chamber 20.7, a plurality of liquid discharge branch pipes 20.8 are provided, and all the liquid discharge branch pipes 20.8 are arranged around the circumferential direction of the anode-cathode isolation filter cartridge 20.2.

[0058] In the present invention, the anode-cathode isolation filter cartridge 20.2 functions as an insulator, and only allows part of the electrolyte to pass through. Its structure in this embodiment is specifically as follows: the anode-cathode isolation filter cartridge 20.2 includes three layers; among them, the outer layer is the layer facing the tubular cathode 20.1, and this outer layer is the filter layer, the filter layer is a filter membrane, and the filter membrane is a polypropylene fiber membrane (PP membrane), a polytetrafluoroethylene membrane (PTFE membrane), a nylon membrane, a plastic woven filter cloth or a non-woven fabric; the middle layer is a filter mesh structure, and the aperture of the filter mesh structure is larger than that of the filter membrane; the inner layer is a reticulated rigid circular tube structure, and the aperture of the rigid circular tube structure is larger than that of the filter mesh structure; the rigid circular tube structure and the filter mesh structure are made of plastic or metal materials.

[0059] In the present invention, the tubular anode 20.3 is a hollow tube, which is encapsulated in the center of the anode-cathode isolation filter cartridge 20.2 and fixed between the upper flange head 20.15 and the lower flange head 20.14. In this embodiment, metal oxide coatings are provided on the outer walls of the anode guide rod 20.13 and the tubular anode 20.3, and this metal oxide coating is a functional coating, which can be used to reduce the cell voltage and save energy. Furthermore, the metal oxide coating is one or more mixtures of lead-based, tin-based, ruthenium-based, iridium-based, and tantalum-based materials. Preferably, the tubular anode 20.3 is made of a corrosion-resistant conductive material, and the material is specifically one of titanium and titanium-based composites, platinum and its platinum-based materials, lead and its alloys, and graphite.

[0060] Further, to facilitate better reaction of the electrolyte, a temperature control jacket 20.17 is provided on the outer frame of the tubular cathode 20.1. A cathode temperature control fluid inlet pipe 20.18 and a cathode temperature control fluid outlet pipe 20.19 are provided on the temperature control jacket 20.17. One ends of both the cathode temperature control fluid inlet pipe 20.18 and the cathode temperature control fluid outlet pipe 20.19 are located between the temperature control jacket 20.17 and the tubular cathode 20.1, and the other ends are located outside the temperature control jacket 20.17. Thus, a fluid at a certain temperature can flow between the temperature control jacket 20.17 and the tubular cathode 20.1 through the cathode temperature control fluid inlet pipe 20.18 and the cathode temperature control fluid outlet pipe 20.19, so as to perform constant temperature control on each area of the reaction section. Preferably, the cathode temperature control fluid inlet pipe 20.18 and the cathode temperature control fluid outlet pipe 20.19 are preferably arranged on opposite sides of the tubular cathode 20.1, and the cathode temperature control fluid inlet pipe 20.18 is close to the lower flange head 20.14, and the cathode temperature control fluid outlet pipe 20.19 is close to the upper flange head 20.15. Similarly, a temperature control coiled pipe 20.20 is provided on the tubular anode 20.3. Both ends of the temperature control coiled pipe 20.20 are located outside the liquid inlet shunt chamber 20.4, and the middle section of the temperature control coiled pipe 20.20 is located inside the tubular anode 20.3. A fluid at a certain temperature can enter the inside of the tubular anode 20.3 through the temperature control coiled pipe 20.20, so as to perform constant temperature control on the electrolyte in the anode-cathode isolation filter cartridge 20.2.

[0061] In this embodiment, the master control unit 40 has a PLC controller and is electrically connected to the sulfite solution feeding pump 5, the feeding pump 4, the pH probe 9, the buffer solution feeding pump 8, the ultraviolet lamp group 1.7 of the auxiliary device 1, and the cathode guide rod through the PLC controller, so as to control the operation of each pump and the operation of the ultraviolet lamp group 1.7 by the PLC controller, as well as the current condition through the cathode guide rod. Preferably, the cathode current density flowing through the cathode guide rod is 0.001 - 10 A / cm 2 .

[0062] In addition, the slurry buffer tank 3 is also connected to a vacuum defoaming device 30 to defoam the slurry buffer tank 3. Similarly, the tubular reduction device is also connected to the vacuum defoaming device. A total discharge pipe 50 is provided on the communication pipeline between the slurry buffer tank 3 and the total liquid discharge pipe of the reaction assembly. A pipeline cut-off valve 10 is provided on the total discharge pipe 50. A total feed pipe 60 is provided on the communication pipeline between the slurry buffer tank 3 and the discharge three-way valve 2. A pipeline cut-off valve 10 is also provided on the total feed pipe 60. In this way, the slurry to be reacted can enter the reaction system through the total feed pipe 60, and the slurry after the reaction is completed can be discharged out of the reaction system through the total discharge pipe 50, thereby realizing the continuous production of the system. Of course, in this application, according to actual production needs, all the slurry can be discharged through the total discharge pipe 50 and then a new batch of raw materials can be introduced through the total feed pipe 60. That is, in addition to continuous production, this application can also carry out intermittent production.

[0063] Based on the above analysis, it can be seen that the reaction assembly designed by the present invention can perform liquid-flow continuous electrochemical reduction of graphene oxide, and it has the following advantages. The electrochemical method can use a more environmentally friendly electrolyte. Conventional soluble inorganic salts can serve as conductive carriers and can be recycled through simple solid-liquid separation, avoiding the use of toxic and harmful reagents. At the same time, this device does not require a high-temperature or strong reducing agent environment, and the controllable reduction of graphene oxide can be achieved only by adjusting the current density and the ratio of the electrolyte, which helps to achieve energy conservation and emission reduction.

[0064] The above description is a detailed description of the preferred feasible embodiments of the present invention, but the embodiments are not intended to limit the patent application scope of the present invention. Any equivalent changes or modifications completed under the technical spirit disclosed by the present invention shall fall within the patent scope covered by the present invention.

Claims

1. A reduction system for continuously electrochemically reducing graphene oxide in a liquid flow, characterized in that: It includes a pre-reduction component and a reaction component; the pre-reduction component includes an auxiliary device, a feed pump, a slurry buffer tank, a discharge three-way valve, a sulfite solution storage tank, a sulfite solution feeding pump and a master control unit; the auxiliary device includes an encapsulation tube body, both ends of the encapsulation tube body in the length direction are sealed, one end is equipped with a feed pipe, and the other end is equipped with a discharge pipe; inside the encapsulation tube body, a diversion chamber, a reaction chamber and a confluence chamber are sequentially separated along the length direction; the diversion chamber is communicated with the feed pipe, the confluence chamber is communicated with the discharge pipe, an ultraviolet lamp group and a high-transparency fluid tube are arranged in the reaction chamber, the ultraviolet lamp group and the high-transparency fluid tube are arranged at intervals, the high-transparency fluid tube is made of a light-transmitting material, one end of the high-transparency fluid tube is communicated with the diversion chamber and the other end is communicated with the confluence chamber; the diversion chamber of the auxiliary device is communicated with the discharge end of the feed pump through the feed pipe, the feed end of the feed pump is connected to the slurry buffer tank through a pipeline, the slurry buffer tank is also connected to the first port of the discharge three-way valve, the second port of the discharge three-way valve is communicated with the confluence chamber of the auxiliary device through the discharge pipe, the third port of the discharge three-way valve is connected to the liquid inlet main pipe of the reaction component, and the liquid discharge main pipe of the reaction component is communicated with the slurry buffer tank; the sulfite solution storage tank is connected to the feed pipe of the auxiliary device through the sulfite solution feeding pump; the sulfite solution feeding pump, the feed pump, the ultraviolet lamp group and the cathode guide rod of the reaction component are all electrically connected to the master control unit; The reaction component includes at least one tubular reduction device. When the number of tubular reduction devices is greater than one, all tubular reduction devices are connected in series or in parallel. When the number of tubular reduction devices is greater than two, the connection relationship of all tubular reduction devices also includes a coexistence of series and parallel connections; Each tubular reduction device includes a tubular cathode and a tubular anode, and a cathode-anode isolation filter cartridge is arranged at intervals between the tubular cathode and the tubular anode. The cathode-anode isolation filter cartridge and the tubular cathode are sequentially sleeved on the outside of the tubular anode; A filter layer is arranged on the side wall of the cathode-anode isolation filter cartridge facing the tubular cathode.

2. The reduction system for continuously electrochemically reducing graphene oxide in a liquid flow according to claim 1, wherein: The lower end of the tubular cathode is sealed and fixed with a lower flange head, and the end of the lower flange head facing away from the tubular cathode is provided with a liquid inlet diversion chamber, and a liquid inlet main pipe and a liquid inlet branch pipe are provided on the liquid inlet diversion chamber. One end of the liquid inlet main pipe is located on the outside of the liquid inlet diversion chamber, and the other end is located inside the liquid inlet diversion chamber and communicated with the liquid inlet diversion chamber. One end of the liquid inlet branch pipe is located inside the liquid inlet diversion chamber and communicated with the liquid inlet diversion chamber, and the other end is penetrated by the lower flange head and extends to between the tubular cathode and the anode and cathode isolation filter cartridge; the upper end of the tubular cathode is sealed and fixed with an upper flange head, and the end of the upper flange head facing away from the tubular cathode is provided with a liquid outlet confluence chamber, and the liquid outlet confluence chamber is provided with a liquid discharge branch pipe, a liquid discharge main pipe, a cathode exhaust pipe and an anode exhaust pipe. Tube, one end of the drainage branch pipe is located inside the liquid outlet confluence chamber and is connected to the liquid outlet confluence chamber, the other end is penetrated by an upper flange head and extends to between the tubular cathode and the anode and cathode isolation filter cartridge, one end of the drainage main pipe and the cathode exhaust pipe are both located outside the liquid outlet confluence chamber, the other ends are both located inside the liquid outlet confluence chamber and are connected to the liquid outlet confluence chamber, wherein, inside the liquid outlet confluence chamber, the distance between the end of the drainage branch pipe and the upper flange head is greater than the distance between the end of the drainage main pipe and the upper flange head, but less than the distance between the end of the cathode exhaust pipe and the upper flange head; one end of the anode exhaust pipe is located outside the liquid outlet confluence chamber, the other end is penetrated by an upper flange head from the liquid outlet confluence chamber and extends to the inside of the anode and cathode isolation filter cartridge; The lower end of the anode-cathode isolation filter cartridge is fixedly connected to the lower flange head, and the upper end is fixedly connected to the upper flange head; The lower end of the tubular anode is fixedly connected to the lower flange head, and the upper end is spaced apart from the upper flange head, and the upper end of the tubular anode is located below one end of the anode exhaust pipe located on the inner side of the anode-cathode isolation filter cartridge; an anode guide rod is provided at the upper end of the tubular anode, one end of the anode guide rod is connected to the tubular anode, and the other end passes through a liquid outlet confluence chamber and extends to the outer side of the liquid outlet confluence chamber; the anode guide rod is electrically connected to the main control unit.

3. The reduction system for continuously electrochemically reducing graphene oxide in a liquid flow according to claim 1, characterized in that: The tubular cathode is a metal part, and an insulating rubber layer is provided on its outer wall. Both ends of the tubular cathode are flange plate structures. The upper flange head and the lower flange head are flange plate structures made of insulating material. The tubular cathode is fixedly connected to the upper flange head and the lower flange head by flange connection. When fixedly connected, the flange plate structures at both ends of the tubular cathode are fixedly connected to the flange heads at their ends by fixing parts, wherein the fixing parts include fixing caps and connecting rods, and the connecting rods are simultaneously plugged into the flange plate structure of the tubular cathode and the flange head at their ends. The connecting rod is a metal part, and the fixing cap is an insulating part, which is installed at one end of the connecting rod; the connecting rod is a cathode guide rod, which is electrically connected to the master control unit.

4. The reduction system for continuously electrochemically reducing graphene oxide in a liquid flow according to claim 1, characterized in that: The anode-cathode isolation filter cartridge includes three layers; among them, the outer layer is the layer facing the tubular cathode, and this outer layer is the filter layer. The filter layer is a filter membrane, and the filter membrane is a polypropylene fiber membrane, a polytetrafluoroethylene membrane, a nylon membrane, a plastic woven filter cloth or a non-woven fabric; the middle layer is a filter screen structure, and the pore size of the filter screen structure is larger than that of the filter membrane; the inner layer is a reticular rigid circular tube structure, and the pore size of the rigid circular tube structure is larger than that of the filter screen structure; the rigid circular tube structure and the filter screen structure are made of plastic, ceramic or metal materials.

5. The reduction system for continuously electrochemically reducing graphene oxide in a liquid flow according to claim 1, wherein: An insulating glue layer is provided on the outer wall of the tubular cathode, and the inner wall is a non-smooth metal surface.

6. The reduction system for continuously electrochemically reducing graphene oxide in a liquid flow according to claim 1, characterized in that: Metal oxide coatings are provided on the outer walls of the anode guide rod and the tubular anode, and the metal oxide coatings are one or more mixtures of lead-based, tin-based, ruthenium-based, iridium-based, tantalum-based materials.

7. The reduction system for continuously electrochemically reducing graphene oxide in a liquid flow according to claim 1, characterized in that: The encapsulation tube body is a cylindrical structure and is made of a light-tight material; a reflective coating is provided on the inner wall of the encapsulation tube body.

8. The reduction system for continuously electrochemically reducing graphene oxide in a liquid flow according to claim 1, wherein: A number of high-transparency fluid tubes are provided, and the ultraviolet lamp group has a number of ultraviolet lamp bars, and the number of ultraviolet lamp bars and all the high-transparency fluid tubes are arranged in an alternating manner.

9. The reduction system for continuously electrochemically reducing graphene oxide in a liquid flow according to claim 1, wherein: The second port of the discharge three-way valve is also communicated with the feed end of the feed pump through a pipeline, and a pipeline stop valve is installed on the pipeline.

10. The reduction system for continuously electrochemically reducing graphene oxide in a liquid flow according to claim 1, wherein: The pre-reduction assembly further includes a pH probe, a pH buffer solution storage tank and a buffer solution feeding pump; the pH probe is installed on the confluence chamber of the auxiliary device, and the pH buffer solution storage tank is connected to the feed pipe of the auxiliary device through the buffer solution feeding pump; both the buffer solution feeding pump and the pH probe are electrically connected to the master control unit.

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