System for purifying CO2 through low-energy electron radiation and application method

Abstract

The invention discloses a system for purifying CO2 through low-energy electron radiation and an application method, and the system comprises a reaction bin, the bottom of the reaction bin is provided with a lifting sample table, the upper part of the reaction bin is provided with a flange interface, and the reaction bin is provided with a vacuum valve and a heater; the electron gun is hermetically connected with the reaction bin; the gas-phase sample introduction device is connected with the reaction bin through a first guide pipe, the gas-phase sample introduction device is provided with a CO2 sample introduction end and a pure water sample introduction end, the CO2 sample introduction end and the pure water sample introduction end are both provided with flow valves, and a heating device is arranged at the bottom of the gas-phase sample introduction device; and the product collection and analysis device is connected to the reaction bin. The method has the following beneficial effects that the mixing ratio of CO2 and water vapor in the reaction, catalytic reaction substances, the distance from the lifting sample table to the electron gun and a plurality of variables can adopt control variables to detect generated substances in a reaction formula, so that parameters such as energy and flow intensity of low-energy electron beams are optimized, and efficient radiation reduction of CO2 in the ionization radiation reduction device is realized.

Description

Technical Field

[0001] The present invention belongs to the field of energy and chemical material conversion, and specifically relates to a system and application method for purifying CO2 by low-energy electron radiation. Background Art

[0002] Using renewable energy to convert CO2 into high-value chemicals or fuels is an effective way to achieve sustainable energy development and reduce the concentration of CO2 in the environment. The activation of CO2 molecules is the key to the process of CO2 resource utilization. The standard formation enthalpy of CO2 is △ = -394.4 kmol, which is thermodynamically stable and kinetically inert, making it difficult to activate and facing huge challenges in resource utilization. Traditional thermal catalytic CO2 conversion requires high energy consumption, resulting in excessive reliance on fossil fuel combustion in the thermal catalytic process. CO2 conversion methods driven by renewable energy include electrocatalysis, photocatalysis, plasma conversion and ionizing radiation reduction. Among them, the radiation transient species generated by ionizing radiation can quickly break through the activation energy barrier of CO2 molecules, thereby promoting the reduction reaction of CO2. Compared with the traditional thermal catalysis of hydrogen attacking CO2 and the photoelectrocatalysis of proton attacking CO2, the ionizing radiation reduction reaction driven by radiation transient species is more active. There are two main pathways for ionizing radiation CO2 reduction: high-energy radiation reduction and low-energy electron attachment dissociation. The high-energy radiation CO2 reduction reaction is based on the principle of water radiation free radical chemistry. It uses high-energy rays (X-rays, gamma rays or electron beams) to radiate and decompose water at room temperature and pressure to produce a large number of active free radicals (·OH, eaq-, etc.) that effectively react with CO2 to produce products such as CH4 and CH3OH. The energy of high-energy rays is high, far exceeding the energy range of C=O bond breaking and O=O bond generation in CO2 reduction. In addition, high-energy rays have strong penetrating power, and radiation protection measures are complex. The engineering implementation of high-energy ray radiation reduction of CO2 is also relatively difficult. Low-energy electrons can directly dissociate CO2, which is an energy-controllable ionizing radiation CO2 reduction pathway. As one of the mechanisms for the origin of early oxygen on Earth, low-energy electrons near the ionosphere in the atmosphere can reduce CO2 to produce O2 by attaching and dissociating.

[0003] Although there have been reports on the electron-attached reduction of CO2, the process still has problems such as low reaction efficiency and poor product selectivity. It is necessary to achieve efficient ionizing radiation reduction of CO2 through strategies such as low-energy electron beam control and the construction of dielectric materials and catalytic materials. However, current research on electron-attached reduction of CO2 is more focused on the momentum distribution of reduced fragments and the dissociation mechanism of CO2. There is a lack of devices that can produce a large number of low-energy electrons, as well as a cavity environment that can carry out electron-attached reduction of CO2 on a macroscopic scale. At present, this weakly bound low-energy electron is mainly produced by high-voltage discharge. How to optimize the parameters such as low-energy electron beam energy, focusing degree and flow intensity to achieve efficient radiation reduction of CO2 requires the development of ionizing radiation reduction devices. Summary of the invention

[0004] An object of the present invention is to solve at least the above problems and / or disadvantages and to provide at least the advantages which will be described hereinafter.

[0005] In order to achieve these purposes and other advantages according to the present invention, a system for purifying CO2 with low-energy electron radiation is provided, comprising:

[0006] A reaction chamber, the bottom of which is provided with a lifting sample platform for placing catalytic materials, a flange interface is provided above the reaction chamber directly opposite to the lifting sample platform, and a vacuum valve and a heater are provided on the reaction chamber;

[0007] An electron gun, which is sealed and connected to the reaction chamber via a flange interface;

[0008] A gas phase sampling device, which is connected to the reaction chamber through a first conduit, the first conduit is provided with a vacuum pump, a CO2 sampling end and a pure water sampling end are respectively provided on one side of the gas phase sampling device, the CO2 sampling end and the pure water sampling end are both provided with flow valves, and a heating device is provided at the bottom of the gas phase sampling device;

[0009] The product collection and analysis device is connected to the reaction chamber through a second conduit.

[0010] Preferably, the lifting sample platform is arranged at the bottom of the reaction chamber 1 in the following manner:

[0011] The bottom flange of the reaction chamber is connected to a sealed tank, a step is arranged inside the sealed tank, the lifting sample platform includes a servo electric cylinder, a lifting column and a fixed platform, and a catalyst display platform is arranged on the upper end of the lifting column, wherein:

[0012] The fixed platform is fixedly arranged on the step of the sealing tank, the middle part of the fixed platform is hollow and fixedly connected with a lifting column, and the servo electric cylinder is fixedly installed at the bottom of the fixed platform and electrically controls the lifting column.

[0013] Preferably, the electron gun structure comprises:

[0014] An insulating ceramic tube, the upper end of which is arranged in a corrugated shape, one side of which is connected to an ion pump for maintaining the vacuum inside the electron gun through an exhaust tee pipe, and an anode end is arranged in the middle of the insulating ceramic tube;

[0015] An integrally formed CF63 sealing flange is provided in the middle of the insulating ceramic tube, and the electron gun is sealed and connected to the reaction chamber via the CF63 sealing flange;

[0016] The lower end of the insulating ceramic tube is provided with an annular groove, the outer periphery of the annular groove is provided with a heat dissipation mechanism, the bottom of the insulating ceramic tube is fixedly connected with a copper heat conducting ring and an insulating ceramic ring in sequence by bolts, a titanium window is sandwiched between the copper heat conducting ring and the insulating ceramic ring, and a graphite heat dissipation ring is provided on the side of the titanium window close to the reaction chamber;

[0017] The sealing cover is sealed and connected to the top of the insulating ceramic tube. The upper end of the sealing cover is provided with a power input terminal. The center of the bottom end of the sealing cover is fixedly installed with a cathode terminal extending into the insulating ceramic tube. The lower end of the cathode terminal is fixedly installed with a focusing electrode.

[0018] Preferably, the heat dissipation mechanism comprises:

[0019] A plurality of annular heat dissipation layers are sleeved on the annular groove, the plurality of annular heat dissipation layers are arranged vertically, and the upper and lower end surfaces of the plurality of annular heat dissipation layers are sealed and connected to the two sides of the annular groove;

[0020] A heat dissipation pipe, the inner ring of which is vertically fixedly connected to the outer edges of multiple annular heat dissipation layers, and the upper end of the heat dissipation pipe is fixedly connected to the CF63 sealing flange;

[0021] The liquid-cooled heat dissipation pipe is arranged in a plurality of connected S-shapes and is surrounded and penetrated in a plurality of annular heat dissipation plates. The liquid-cooled heat dissipation pipe and the plurality of annular heat dissipation layers are connected at the connection points with sealing heat-resistant glue. The input and output ends of the liquid-cooled heat dissipation pipe are externally connected to the liquid-cooled heat dissipation system.

[0022] Preferably, the cathode end is made of barium tungsten material; the inner ring surface of the insulating ceramic tube can be coated with boron nitride and yttrium oxide, and the first fixed layer, the second fixed layer and multiple annular heat dissipation plates can be made of polyimide (PI) material or polyphenylene ether (PPO) material, high-purity silicon carbide ceramics and other materials.

[0023] Preferably, the catalyst material on the lifting sample stage is one of metal oxides, perovskite-type composite oxides and spinel-type composite oxides.

[0024] A method for purifying CO2 by low-energy electron radiation using the system for purifying CO2 by low-energy electron radiation comprises the following steps:

[0025] Step 1: Start the vacuum valve to evacuate the reaction chamber, connect the cathode end of the electron gun to an external power source, and connect the anode end to ground with a wire to form a zero potential;

[0026] Step 2: Turn on the heater and the heating device to preheat the reaction chamber and the gas phase injection device. At this time, the liquid cooling heat pipe on the electron gun begins to inject coolant to start heat dissipation;

[0027] Step 3: Under the control of the flow valve, a certain amount of CO2 and pure water are introduced, the CO2 injection volume range is set within 0-100mL / min±1.0%FS, and the pure water injection volume range is set between 25ul and 5ml;

[0028] Step 4: Turn on the vacuum pump to introduce the mixed gas into the reaction chamber, and at the same time control the servo electric cylinder to raise and lower the lifting column, and then start the electron gun;

[0029] Step 5: Open the product collection and analysis device to collect the reaction products, and finally extract the reaction products for gas chromatography analysis.

[0030] Preferably, in step 1, the output voltage of the cathode end external power supply is 0 to -80 kV, the cathode end current is controlled at 0 to 2.5 A, and the anode end adopts 25 mm 2 electric wire.

[0031] Preferably, in step 4, the lifting height range of the lifting column is adjusted within 1-100 mm, and the repeatability positioning accuracy is set within ±0.01 mm.

[0032] Preferably, in step 5, the amount of the extracted reaction product is 1 ml.

[0033] The present invention includes at least the following beneficial effects: by changing the mixing ratio of CO2 and water vapor in the reaction, the reaction product can be tested, and at the same time, the distance between the catalytic reaction material and the lifting sample stage to the electron gun can be adjusted, which can further achieve the generation of a large number of low-energy electrons, and then optimize the parameters such as the low-energy electron beam energy, focusing degree and current intensity, so as to realize the efficient radiation reduction of CO2 in the ionizing radiation reduction device.

[0034] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a system for purifying CO2 by low-energy electron radiation;

[0036] Figure 2 This is the front view of the electron gun;

[0037] Figure 3 This is a bottom view of the electron gun;

[0038] Figure 4 This is a cross-sectional diagram of the electron gun.

[0039] Markings in the figure: 1. Reaction chamber, 2. Electron gun, 3. Gas phase injection device, 4. Vacuum valve, 5. Vacuum pump 5, 6. CO2 injection end, 7. Pure water injection end, 8. Heating device, 9. Product collection and analysis device, 30. Sealed tank, 31. Servo electric cylinder, 32. Lifting column, 33. Fixed table, 34. Catalyst display table, 35. Steps, 40. Insulating ceramic tube, 41. Copper thermal conductive ring, 42. Insulating ceramic ring, 43. Titanium window, 44. Power input end, 45. Sealing cover, 46. Cathode end, 47. Focusing electrode, 48. Ion pump, 49. Anode end, 51. CF63 sealing flange, 60. Multiple annular heat dissipation layers, 61. Heat dissipation pipe, 63. Liquid-cooled heat dissipation pipe. DETAILED DESCRIPTION

[0040] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0041] It should be understood that the terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0042] It should be noted that in the description of the present invention, the orientation or positional relationship indicated by the term is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0043] In the description of the present invention, unless otherwise clearly stipulated and limited, the terms "installed", "provided with", "mounted / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be a direct connection or an indirect connection through an intermediate medium. It can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] In addition, in the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0045] like Figures 1 to 4 As shown, a system for purifying CO2 with low-energy electron radiation comprises:

[0046] A reaction chamber 1, at the bottom of which a lifting sample platform for placing catalytic materials is provided, a flange interface is provided above the reaction chamber 1 directly opposite the lifting sample platform, and a vacuum valve 4 and a heater 10 are provided on the reaction chamber 1;

[0047] The electron gun 2 is sealed and connected to the reaction chamber 1 through a flange interface;

[0048] A gas phase sampling device 3 is connected to the reaction chamber 1 through a first conduit, a vacuum pump 5 is provided on the first conduit, a CO2 sampling end 6 and a pure water sampling end 7 are provided on one side of the gas phase sampling device 3, both the CO2 sampling end 6 and the pure water sampling end 7 are provided with flow valves, and a heating device 8 is provided at the bottom of the gas phase sampling device 3;

[0049] The product collection and analysis device 9 is connected to the reaction chamber 1 through a second conduit.

[0050] Working principle:

[0051] When the experimenter needs to use this device to reduce the introduced CO2 combined with water vapor and generate carbon-based products such as CH4 and CO, first confirm that the vacuum pump 5 on the gas phase injection device 3 is in the closed state, then connect the vacuum valve 4 on the reaction chamber 1 to the vacuum pump to evacuate the reaction chamber 1, and then close the vacuum valve 4. Under the control of the flow valve, a certain amount of CO2 and pure water are introduced into the CO2 injection port 6 and the pure water injection port 7, and the heating device 8 is started at the same time to heat the pure water entering the gas phase injection device 3 and convert it into water vapor, thereby heating the water vapor and CO2 to achieve full mixing. Then turn on the vacuum pump 5, and the vacuum pump 5 draws the water vapor and CO2 mixed gas in the gas phase injection device 3 into the reaction chamber 1.

[0052] Then, the lifting sample stage in the reaction chamber 1 is controlled to drive the catalyst to rise and fall to the target height. At this time, the electron gun 2 is turned on and the heater 10 is started at the same time. Under the action of the electron gun 2, the CO2 and water vapor in the reaction chamber 1 react with the catalytic substance on the lifting sample stage to produce carbon-based products such as CH4 and CO, and release a certain amount of oxygen.

[0053] After the product inside the reaction chamber 1 is fully reacted, the gas sampling valve and the sample guide valve on the product collection and analysis device 9 can be opened. The gas sampling valve can collect the gas in the reaction chamber 1, and at the same time, the collected gas is introduced into one of the multiple collection bottles in combination with the sample guide valve, and then the gas in the collection bottle is introduced into the waste gas collection bottle through the conduit containing the vacuum pump 5 inserted into the collection bottle. After performing the above operation three times, the gas in the collection bottle is retained for the fourth time. Then, according to the above steps, the amount of CO2 and pure water is changed for multiple tests, and finally the generated product is passed into other collection bottles, and finally the reaction products in multiple collection bottles are extracted and analyzed by gas chromatography for experimental comparison.

[0054] In the above technical solution, the lifting sample stage is arranged at the bottom of the reaction chamber 1 in the following manner:

[0055] The bottom flange of the reaction chamber 1 is connected to a sealed tank 30, and a step 35 is arranged inside the sealed tank 30. The lifting sample platform includes a servo electric cylinder 31, a lifting column 32 and a fixed platform 33. The upper end of the lifting column 32 is provided with a catalyst display platform 34, wherein:

[0056] The fixed platform 33 is fixedly arranged on the step 35 of the sealing tank 30 . The middle of the fixed platform 33 is hollow and fixedly connected with the lifting column 32 . The servo electric cylinder 31 is fixedly installed at the bottom of the fixed platform 33 and electrically controls the lifting column 32 .

[0057] Through the above arrangement, the experimenter can adjust the height of the lifting column 32 by controlling the servo electric cylinder 31 located on the fixed platform 33 to test the influence of the distance between the electron gun 2 and the catalyst display platform 34 on the CO2 and water vapor reduction reaction. The setting of the step 35 ensures the structural stability of the lifting sample platform.

[0058] At the same time, the bottom of the reaction chamber 1 is sealed with the sealing tank 30 through a flange, ensuring that the reaction chamber 1 is sealed as a whole. When the catalyst needs to be replaced to test the effect on the reduction of the reactants, the catalyst on the lifting sample table can be replaced by disassembling the flange interface.

[0059] In the above technical solution, the structure of the electron gun 2 includes:

[0060] An insulating ceramic tube 40, the upper end of which is arranged in a corrugated shape, one side of the insulating ceramic tube 40 is connected to an ion pump 48 for maintaining the vacuum inside the electron gun 2 through an exhaust tee pipe, and an anode terminal 49 is arranged in the middle of the insulating ceramic tube;

[0061] An integrally formed CF63 sealing flange 51 is provided in the middle of the insulating ceramic tube 40, and the electron gun 2 is sealedly connected to the reaction chamber 1 via the CF63 sealing flange 51;

[0062] The lower end of the insulating ceramic tube 40 is provided with an annular groove, and a heat dissipation mechanism is arranged on the outer periphery of the annular groove. A copper heat conducting ring 41 and an insulating ceramic ring 42 are fixedly connected to the bottom of the insulating ceramic tube 40 in sequence by bolts. A titanium window 43 is sandwiched between the copper heat conducting ring 41 and the insulating ceramic ring 42. A graphite heat dissipation ring (not shown) is arranged on the side of the titanium window 43 close to the reaction chamber 1;

[0063] The sealing cover 45 is sealed and connected to the top of the insulating ceramic tube 40. A power input terminal 44 is provided at the upper end of the sealing cover 45. A cathode terminal 46 extending into the insulating ceramic tube 40 is fixedly installed at the center of the bottom end of the sealing cover 45. A focusing electrode 47 is fixedly installed at the lower end of the cathode terminal 46.

[0064] Through the above arrangement, the electron gun 2 is sealed and connected to the reaction chamber 1 through the CF63 sealing flange 51 in the middle thereof. At this time, the CF63 sealing flange 51 and the following parts on the electron gun 2 are all placed in the reaction chamber 1, and the CF63 sealing flange 51 ensures the airtightness inside the reaction chamber 1.

[0065] When the electron gun 2 is started, the cathode terminal 46 is connected to a 0-80 kV voltage through the power input terminal 44, and the filament on the cathode terminal 46 escapes electrons under high temperature conditions. At this time, the anode is grounded to form a zero point, so the anode terminal 49 forms a potential difference relative to the cathode terminal 46, and the anode terminal 49 can accelerate the escaped electrons so that the electrons on the cathode terminal 46 can penetrate the titanium window 43. The focusing electrode 47 is connected to the power input terminal 44 and connected to an external DC power supply, so that the emitted electrons can be gathered. The setting of the ion pump 48 ensures that the inside of the electron gun 2 is always in a vacuum state, and then passes through the titanium window 43 to reach the catalyst display stand 34 inside the reaction chamber 1, and then participates in the reduction reaction of CO2 and water vapor together with the catalyst. The copper heat conductive ring 41 and the insulating ceramic ring 42 on the titanium window 43 are used to dissipate the heat on the titanium window 43, ensuring that the titanium window 43 will not be melted through when adjusting parameters such as electron beam energy and current intensity. The setting of the heat dissipation mechanism ensures that the electron gun 2 as a whole can operate within a normal range. The setting of the sealing cover 45 ensures the airtightness of the overall structure of the insulating ceramic tube 40.

[0066] In the above technical solution, the heat dissipation mechanism includes:

[0067] A plurality of annular heat dissipation layers 60 are sleeved on the annular groove. The plurality of annular heat dissipation layers 60 are arranged vertically. The upper and lower end surfaces of the plurality of annular heat dissipation layers 60 are sealed and connected to the two sides of the annular groove (see Figure 4 Mark A);

[0068] The heat dissipation pipe 61, whose inner ring is vertically fixedly connected to the outer edges of the plurality of annular heat dissipation layers 60, and the upper end of the heat dissipation pipe 61 is fixedly connected to the CF63 sealing flange 51;

[0069] The liquid-cooled heat dissipation pipe 63 is arranged in a plurality of connected S-shapes and is surrounded and penetrated in a plurality of annular heat dissipation plates 60. A sealing heat-resistant glue is arranged at the connection between the liquid-cooled heat dissipation pipe 63 and the plurality of annular heat dissipation layers 60. The input and output ends of the liquid-cooled heat dissipation pipe 63 are externally connected to the liquid-cooled heat dissipation system.

[0070] Through the above arrangement, when the electron gun 2 is in operation, the electron gun body is affected by the internal electron temperature accumulation and the heat conduction of the reaction chamber 1. Through the arrangement of multiple annular heat dissipation layers 60, the temperature generated inside the electron gun 2 can be conducted to the outside of the insulating ceramic tube 40 through the multiple annular heat dissipation layers 60 for heat dissipation. The structure in which the heat dissipation pipe 61 is sleeved outside the multiple annular heat dissipation layers 60 ensures the structural stability of the multiple annular heat dissipation layers 60. At the same time, the multiple interlayer gaps formed between the multiple annular heat dissipation layers 60 can absorb the high temperature generated in the reaction chamber 1 and the high temperature conducted from the inside of the electron gun 2, and dissipate heat through the heat dissipation liquid flowing in the liquid-cooled heat dissipation pipe 63, thereby further increasing the heat dissipation efficiency of the electron gun 2. The two end surfaces of the multiple annular heat dissipation layers 60 are sealed and connected to the two side surfaces of the annular groove, and the upper end of the heat dissipation pipe 61 is fixedly connected to the CF63 sealing flange 51, thereby ensuring that when the electron gun 2 is fixedly connected to the reaction chamber 1, the airtightness inside the reaction chamber 1 can be ensured, and air is prevented from flowing into the reaction chamber 1 from the gap on the electron gun 2. At the same time, a sealing heat-resistant glue is arranged between the liquid-cooled heat dissipation pipe 63 and the multiple annular heat dissipation layers 60 to ensure that the internal environment of the reaction chamber 1 is maintained in a vacuum state.

[0071] In the above technical solution, the cathode end is made of barium tungsten material; the inner ring surface of the insulating ceramic tube 40 can be coated with boron nitride and yttrium oxide, and the heat dissipation pipe 61 and multiple annular heat dissipation layers 60 can be made of polyimide (PI) material or polyphenylene ether (PPO) material, high-purity silicon carbide ceramics and other materials.

[0072] Through the above arrangement, the barium tungsten cathode is used as a thermal electron emission material. When the barium tungsten cathode is heated to a certain temperature, it can emit a large amount of electrons. Polyimide (PI), material or polyphenylene ether (PPO) material, high-purity silicon carbide ceramics and other materials ensure that the heat pipe 61 and the plurality of annular heat dissipation layers 60 have good toughness and good heat dissipation and insulation properties. The selection of the above materials ensures that the electron gun 2 has high heat dissipation and insulation properties.

[0073] In the above technical solution, the catalyst material located on the lifting sample stage is one of metal oxides, perovskite-type composite oxides, and spinel-type composite oxides.

[0074] Through the above settings, metal oxides, perovskite-type composite oxides, and spinel-type composite oxides can greatly improve the reduction reaction efficiency of CO2 and water vapor. Different reaction products can ensure that the effect of catalysts on the reaction rate of CO2 and water vapor can be tested under the same other conditions.

[0075] Embodiment 1:

[0076] A method for purifying CO2 by low-energy electron radiation comprises the following steps:

[0077] Step 1: First, ensure that the vacuum pump 5 is turned off and the product collection and analysis device 9 is not connected to the reaction chamber 1. Start the vacuum valve 4 to evacuate the reaction chamber 1. The cathode terminal 46 on the electron gun 2 is connected to a power supply with an output voltage of 0 to -80 kV (the control accuracy is set at ±1%). The current of the cathode terminal 46 is controlled within 0 to 2.5 A to ensure that the cathode terminal 46 can be heated to 1050°C to meet our experimental beam requirements. At the same time, the anode terminal 49 adopts a 25 mm 2 The wire is grounded to form a zero potential, and the focusing electrode 47 is connected to an external DC power supply through the power input terminal 44;

[0078] Step 2: Turn on the heater 10 and the heating device 8 to preheat the reaction chamber 1 and the gas phase injection device 3. At this time, start injecting coolant into the liquid cooling pipe 63 on the electron gun 2 to start heat dissipation in advance, and start the ion pump 48 to evacuate the electron gun 2;

[0079] Step 3: Under the control of the flow valve, a certain amount of CO2 and pure water are introduced, the CO2 injection volume range is set within 0-100mL / min±1.0%FS, and the pure water injection volume range is set between 25ul and 5ml, and wait for 10 to 15 minutes under the action of the heating device 8;

[0080] Step 4: Turn on the vacuum pump 5 to pass the mixed gas into the reaction chamber 1, start the electron gun 2, and control the servo electric cylinder 31 to lift the lifting column 32. The lifting height range is 1-100mm, and the repeat positioning accuracy is set within ±0.01mm. After adjusting to the target height, finally start the electron gun 2;

[0081] Step 5: Open the product collection and analysis device 9, extract the products generated by different CO2 and water vapor mixing ratios from the multiple collection bottles inside, collect the reaction products in the collection bottles, and finally extract 1 ml of the reaction products for gas chromatography analysis.

[0082] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A system for purifying CO2 by low-energy electron radiation, characterized in that: include: A reaction chamber, the bottom of which is provided with a lifting sample platform for placing catalytic materials, a flange interface is provided above the reaction chamber directly opposite to the lifting sample platform, and a vacuum valve and a heater are provided on the reaction chamber; An electron gun, which is sealed and connected to the reaction chamber via a flange interface; A gas phase sampling device, which is connected to the reaction chamber through a first conduit, the first conduit is provided with a vacuum pump, a CO2 sampling end and a pure water sampling end are respectively provided on one side of the gas phase sampling device, the CO2 sampling end and the pure water sampling end are both provided with flow valves, and a heating device is provided at the bottom of the gas phase sampling device; The product collection and analysis device is connected to the reaction chamber through a second conduit.

2. The system for purifying CO2 by low-energy electron radiation according to claim 1, characterized in that: The lifting sample platform is arranged at the bottom of the reaction chamber 1 and can be arranged as follows: The bottom flange of the reaction chamber 1 is connected to a sealed tank, a step is arranged inside the sealed tank, the lifting sample platform includes a servo electric cylinder, a lifting column and a fixed platform, and a catalyst display platform is arranged on the upper end of the lifting column, wherein: The fixed platform is fixedly arranged on the step of the sealing tank, the middle part of the fixed platform is hollow and fixedly connected with a lifting column, and the servo electric cylinder is fixedly installed at the bottom of the fixed platform and electrically controls the lifting column.

3. The system for purifying CO2 by low-energy electron radiation according to claim 1, characterized in that: The electron gun structure comprises: An insulating ceramic tube, the upper end of which is arranged in a corrugated shape, one side of which is connected to an ion pump for maintaining the vacuum inside the electron gun through an exhaust tee pipe, and an anode end is arranged in the middle of the insulating ceramic tube; An integrally formed CF63 sealing flange is provided in the middle of the insulating ceramic tube, and the electron gun is sealed and connected to the reaction chamber via the CF63 sealing flange; The lower end of the insulating ceramic tube is provided with an annular groove, the outer periphery of the annular groove is provided with a heat dissipation mechanism, the bottom of the insulating ceramic tube is fixedly connected with a copper heat conducting ring and an insulating ceramic ring in sequence by bolts, a titanium window is sandwiched between the copper heat conducting ring and the insulating ceramic ring, and a graphite heat dissipation ring is provided on the side of the titanium window close to the reaction chamber; The sealing cover is sealed and connected to the top of the insulating ceramic tube. The upper end of the sealing cover is provided with a power input terminal. The center of the bottom end of the sealing cover is fixedly installed with a cathode terminal extending into the insulating ceramic tube. The lower end of the cathode terminal is fixedly installed with a focusing electrode.

4. The system for purifying CO2 by low-energy electron radiation according to claim 3, characterized in that: The heat dissipation mechanism comprises: A plurality of annular heat dissipation layers are sleeved on the annular groove, the plurality of annular heat dissipation layers are arranged vertically, and the upper and lower end surfaces of the plurality of annular heat dissipation layers are sealed and connected to the two sides of the annular groove; A heat dissipation pipe, the inner ring of which is vertically fixedly connected to the outer edges of multiple annular heat dissipation layers, and the upper end of the heat dissipation pipe is fixedly connected to the CF63 sealing flange; The liquid-cooled heat dissipation pipe is arranged in a plurality of connected S-shapes and is surrounded and penetrated in a plurality of annular heat dissipation plates. The liquid-cooled heat dissipation pipe and the plurality of annular heat dissipation layers are connected at the connection points with sealing heat-resistant glue. The input and output ends of the liquid-cooled heat dissipation pipe are externally connected to the liquid-cooled heat dissipation system.

5. The system for purifying CO2 by low-energy electron radiation according to claim 4, characterized in that: The cathode end is made of barium tungsten material; the inner ring surface of the insulating ceramic tube can be coated with boron nitride and yttrium oxide, and the heat dissipation pipe and multiple annular heat dissipation plates can be made of polyimide (PI) material or polyphenylene ether (PPO) material, high-purity silicon carbide ceramics and other materials.

6. The system for purifying CO2 by low-energy electron radiation according to claim 1, characterized in that: The catalyst material on the lifting sample stage is one of metal oxides, perovskite-type composite oxides and spinel-type composite oxides.

7. A method for purifying CO2 using a system of low-energy electron radiation as claimed in any one of claims 1 to 6, characterized in that: The following steps are involved: Step 1: Start the vacuum valve to evacuate the reaction chamber, connect the cathode end of the electron gun to an external power source, and connect the anode end to ground with a wire to form a zero potential; Step 2: Turn on the heater and the heating device to preheat the reaction chamber and the gas phase injection device. At this time, the liquid cooling heat pipe on the electron gun begins to inject coolant to start heat dissipation; Step 3: Under the control of the flow valve, a certain amount of CO2 and pure water are introduced, the CO2 injection volume range is set within 0-100mL / min±1.0%FS, and the pure water injection volume range is set between 25ul and 5ml; Step 4: Turn on the vacuum pump to introduce the mixed gas into the reaction chamber, and at the same time control the servo electric cylinder to raise and lower the lifting column, and then start the electron gun; Step 5: Open the product collection and analysis device to collect the reaction products, and finally extract the reaction products for gas chromatography analysis.

8. The method according to claim 7, characterized in that In the step 1, the output voltage of the cathode end external power supply is 0 to -80 kV, and the cathode end current is controlled at 0 to 2.5 A; the anode end adopts 25 mm 2 Wire ground.

9. The method according to claim 7, characterized in that: In the step 4, the lifting height range of the lifting column is adjusted within 1-100 mm, and the repeat positioning accuracy is set within ±0.01 mm.

10. The method according to claim 7, characterized in that In the step 5, the amount of the extracted reaction product is 1 ml.

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