A sort of 13 High-abundance CO was prepared by CuO catalytic oxidation. 13 CO2 apparatus and methods

Abstract

This invention provides 13 High-abundance CO was prepared by CuO catalytic oxidation. 13 This invention relates to a CO2 apparatus and method, belonging to the field of stable isotope-labeled compound preparation technology. The apparatus described in this invention is an integrated unit comprising a feed gas supply unit, a fixed-bed reaction unit, a cryogenic collection unit, a partial pressure purification unit, and a tail gas treatment unit connected in series. The fixed-bed reaction unit includes a fixed-bed reactor, a heater, and a temperature sensor. This invention utilizes high-temperature calcined modified CuO catalyst particles, combined with a composite bed structure design of "quartz wool-quartz sand-catalyst-quartz sand," significantly improving conversion efficiency and selectivity; optimizing the purification process, achieving product quality that meets high-end application standards; featuring a novel apparatus design with greatly improved sealing and stability; simple and controllable operation, facilitating industrial scale-up; and being green, safe, and environmentally friendly, aligning with industrial development trends.

Description

Technical Field

[0001] This invention relates to the field of stable isotope-labeled compound preparation technology, and particularly to a method 13 High-abundance CO was prepared by CuO catalytic oxidation. 13 Apparatus and methods for producing CO2. Background Technology

[0002] 13 CO2, as an important stable isotope-labeled compound, possesses irreplaceable application value in several cutting-edge fields such as medical diagnostics, isotope tracing, environmental science, and organic synthesis due to its unique isotopic properties. In the field of medical diagnostics, high abundance... 13 CO2 is used to prepare 13 C-labeled urea is the core raw material, and 13 C-labeled urea breath test is currently the preferred non-invasive detection method for clinical diagnosis of Helicobacter pylori infection, with advantages such as high detection accuracy, good safety, and non-invasiveness, and has been widely used in clinical diagnosis and treatment; in environmental science research, 13 CO2 can be used as a tracer to track global carbon cycle processes, study greenhouse gas emissions and migration patterns, and provide key data support for climate change research; in the field of organic synthesis... 13 CO2 as 13 C-labeled drug molecules and core intermediates for fine chemicals are of great significance for improving drug development efficiency, optimizing synthesis processes, and ensuring drug quality. With the rapid development of related fields, the market demand for high-purity (≥99.5%) and high-abundance (…) 13 C abundance recovery ≥99% 13 The demand for CO2 continues to grow, and the development of efficient, green, and scalable preparation technologies has become a core need and research hotspot for the industry.

[0003] Currently, preparation in industry and laboratories 13 The main methods for processing CO2 include acid hydrolysis, pyrolysis, and catalytic oxidation. Among these, acid hydrolysis is the most common. 13 C-labeled carbonates (such as...) 13 Using calcium carbonate (C-) as a raw material, it reacts with strong acids (such as hydrochloric acid and sulfuric acid) to produce... 13 CO2, this method has high raw material costs ( 13 The inherent drawbacks of C-labeled carbonates (high price), violent and difficult-to-control reaction process, easy contamination of products by acid mist leading to decreased purity, and the generation of large amounts of acidic waste liquid requiring additional treatment make it difficult to meet the needs of large-scale and green production; pyrolysis requires decomposition at high temperatures above 800℃. 13 C-labeled organic compounds (such as C-labeled organic compounds) 13C-oxalic acid not only has high energy consumption but is also prone to side reactions (such as carbonization of organic matter), leading to loss of product isotopic abundance and reduced product quality. Furthermore, the high-temperature reaction places stringent requirements on equipment, increasing production costs and safety risks. Catalytic oxidation methods... 13 Using CO as a raw material, the process is achieved through the catalytic action of a catalyst. 13 CO 13 The oxidation and conversion of CO2 has advantages such as high raw material utilization, relatively mild reaction conditions, easy product separation, and no waste liquid generation, and has become a current trend. 13 The mainstream technological path for CO2 production.

[0004] However, existing catalytic oxidation methods for preparation 13 CO2 technology still faces many critical challenges that urgently need to be addressed, severely limiting its industrial application and product quality improvement: Firstly, the catalytic system lacks selectivity. Existing catalysts (such as Pt / C and Pd / Al2O3) suffer from uneven distribution of active sites and poor catalytic selectivity, leading to… 13 Incomplete CO oxidation results in trace amounts of residual CO impurities in the product, severely affecting product purity and making it difficult to meet the stringent requirements of medical, high-end synthesis, and other fields. Secondly, the reaction temperature control precision is low; existing fixed-bed reactors mostly use single-stage temperature control, leading to uneven temperature distribution in the catalytic bed. Localized overheating can easily cause catalyst deactivation, and excessively high temperatures can trigger isotope fractionation, resulting in… 13 The C abundance recovery rate is low (usually below 95%); third, the system sealing is poor, and the sealing performance of the connection between the units of the existing equipment is insufficient, which easily introduces ordinary CO2 from the air, causing dilution of the product isotope abundance and reducing the application value of the product; fourth, the product separation and purification process is cumbersome, the existing low temperature capture efficiency is low, and the impurities are not completely removed, requiring additional purification steps such as distillation, which increases the production process and cost; in addition, the existing preparation equipment lacks an integrated design, and the connection between the units is not smooth, resulting in a complex operation process and a high product loss rate (usually above 5%), making it difficult to achieve large-scale and standardized production.

[0005] Therefore, it is necessary to overcome existing technological bottlenecks and develop a catalyst with high catalytic efficiency and high product purity. 13 It boasts high C abundance recovery, is easy to operate, and is readily scalable for industrial production. 13 CO catalytic oxidation to prepare 13 The CO2 method addresses the core shortcomings of existing technologies and has significant academic research value and industrial application prospects for promoting the development of the stable isotope labeled compound industry and meeting the needs of high-end applications in multiple fields. Summary of the Invention

[0006] The purpose of this invention is to provide a 13 High-abundance CO was prepared by CuO catalytic oxidation. 13CO2 devices and methods, through synergistic optimization of the catalytic system, reaction parameters, and device structure, achieve... 13 CO 13 This technology enables efficient and targeted conversion of CO2, simultaneously addressing key technical challenges in existing technologies such as low product purity, isotope abundance loss, system contamination, and operational complexity, thus paving the way for high-abundance CO2 conversion. 13 This provides technical support for the large-scale production of CO2.

[0007] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides 13 High-abundance CO was prepared by CuO catalytic oxidation. 13 The CO2 device is an integrated device, which includes a feed gas supply unit, a fixed bed reaction unit, a cryogenic collection unit, a partial pressure purification unit, and a tail gas treatment unit connected in series. The fixed-bed reaction unit includes a fixed-bed reactor, a heater, and a temperature sensor.

[0008] Preferably, the raw gas supply unit includes 13 The system includes a CO feed gas cylinder, a mass flow controller, and a gas pretreatment module; a cryogenic collection unit comprising a coil-type precooler, a refrigeration unit, and a collection cylinder; a partial pressure purification unit comprising series cylinders, a precision valve assembly, and a pressure sensor; and a tail gas treatment unit comprising an activated carbon adsorption tank, an online CO analyzer, a vent, and a safety alarm device.

[0009] The present invention also provides 13 High-abundance CO was prepared by CuO catalytic oxidation. 13 The CO2 method includes the following steps: 1) Pretreatment of the apparatus: High-purity nitrogen gas is used to treat the apparatus. 13 High-abundance CO was prepared by CuO catalytic oxidation. 13 The CO2 device undergoes segmented purging and vacuuming. 2) Constructing the catalytic system: The fixed-bed reactor is sequentially filled with quartz wool, a first layer of quartz sand, CuO catalyst particles, and a second layer of quartz sand. The fixed-bed reactor is preheated to the reaction temperature and then kept at that temperature. 3) Directed catalytic oxidation reaction: 13 CO feed gas is continuously fed into the preheated fixed-bed reactor. 13 CO undergoes a directed oxidation reaction with a CuO catalyst bed to produce... 13 CO2 products; 4) Low-temperature capture and deep purification: 13 The CO2 products were sequentially subjected to cooling pretreatment, low-temperature condensation and collection, and multi-stage partial pressure deep purification to obtain high-abundance CO2. 13 CO2; 5) Harmless treatment of exhaust gas: The exhaust gas in the reaction process is purified by adsorption using modified activated carbon to obtain the adsorbed exhaust gas.

[0010] Preferably, the purity of the high-purity nitrogen gas in step 1) is ≥99.99%, the pressure of the segmented purging is 0.4~0.6MPa, the time of the segmented purging is 10~20min, the rate of the segmented purging is 50~100mL / min, the rate of vacuuming is ≥10L / min, and the vacuum is evacuated to a vacuum degree ≤30 mTorr.

[0011] Preferably, in step 2), the thickness of the first layer of quartz sand is 50-100 mm, the height of the CuO catalyst particles is 500-700 mm, the thickness of the second layer of quartz sand is 50-100 mm, the particle size of the CuO catalyst particles is 0.5-2.0 mm, and the specific surface area is ≥10 m². 2 / g, the CuO catalyst particles are calcined and modified CuO catalyst particles.

[0012] Preferably, the fixed-bed reactor in step 2) adopts an isothermal structure with ≥4 temperature control sections, a temperature control accuracy of ±3℃, an inner diameter of 30~50mm, a reaction temperature of 300~600℃, and a holding time of 30~60min.

[0013] Preferably, step 3) is described 13 The flow rate of the CO feed gas is 10~50 mL / min. 13 CO feed gas 13 The C abundance is 85–99.99 atomic%. 13 The purity of the CO feed gas is ≥98%; The directional oxidation reaction is carried out at a temperature of 300~600℃, a pressure of 0.1~0.3MPa, and a time of 3~8h.

[0014] Preferably, the temperature for the low-temperature condensation collection in step 4) is -100~-80℃, and the low-temperature condensation collection uses a collection cylinder with a volume of 0.5~2.0L, made of 316L stainless steel, and with a pressure resistance of ≥4.0MPa. The specific process of multi-stage partial pressure deep purification is as follows: the low-temperature condensed and captured... 13 CO2 is transferred between two series-connected cylinders through a pressure reduction process, which is repeated 2 to 3 times, with a pressure reduction of 0.05 to 0.1 MPa.

[0015] Preferably, during the adsorption purification process in step 5), the space velocity of the exhaust gas is 100~300 h⁻¹. -1 The adsorption purification process is carried out at room temperature; the exhaust gas contains trace amounts of unreacted substances. 13 CO and other exhaust gases produced during the reaction; The modified activated carbon has an adsorption efficiency of ≥99% for CO in exhaust gas; the CO concentration in the exhaust gas after adsorption is less than 20 mg / m³. 3 .

[0016] The beneficial effects of this invention are: 1) Innovative Catalytic System, Significantly Improved Conversion Efficiency and Selectivity: This invention innovatively uses CuO catalyst particles modified by high-temperature calcination, combined with a composite bed structure design of "quartz wool-quartz sand-catalyst-quartz sand," optimizing the distribution of catalytic active sites and significantly improving catalytic selectivity and activity. Compared with existing Pt / C and Pd / Al2O3 catalysts, the CuO catalyst reduces costs by more than 60% and can achieve… 13 The CO conversion rate is ≥99.9%, and the residual CO concentration in the product is ≤50ppm, completely solving the technical pain point of incomplete oxidation in existing technologies; at the same time, the reaction temperature is mild, effectively avoiding isotope fractionation caused by high temperature. 13 C abundance recovery rate ≥99%, significantly better than existing processes (existing processes) 13 C abundance recovery is typically below 95%.

[0017] 2) Optimized purification process, achieving product quality standards for high-end applications: A combined purification process of "pre-cooling dehydration - low-temperature collection - multi-stage partial pressure" was constructed. Through the synergistic effect of multiple steps, moisture, inert gases, and unreacted trace elements in the product were effectively removed. 13 CO impurities, 13 The CO2 product has a purity of ≥99.5%, a moisture content of ≤0.1%, and a CO residue concentration of ≤50ppm, which can meet the stringent requirements for high-purity products in fields such as medical diagnosis, isotope tracing, and high-end organic synthesis. Compared with existing purification processes, this invention does not require an additional distillation step, simplifies the process, reduces the product loss rate to below 1%, and significantly improves production efficiency and raw material utilization.

[0018] 3) Novel device design, significantly improved sealing and stability: This invention adopts an integrated device design, with each unit connected in series through corrosion-resistant, highly sealing pipes. All pipes and components are made of 316L stainless steel with excellent sealing properties. The inner wall of the reactor is polished to reduce product adsorption and residue. Combined with a nitrogen purging-vacuum dual pretreatment process, it ensures that there is no residual air in the device, avoiding the dilution of product isotope abundance by ordinary CO2, and protecting the product. 13 The C abundance remains consistent with the raw materials, with no cross-contamination; the equipment is equipped with a high-precision temperature monitoring system, pressure monitoring system, and safety alarm device, with a high degree of automation and significantly improved operational stability.

[0019] 4) Simple and controllable operation, easy to scale up industrially: The device of this invention has a compact structure and achieves precise control of key parameters such as temperature, pressure, and flow rate through a PLC control system. It has a high degree of automation, simplified operation process, and can be operated without professional technicians. The process route is short and the steps are clear. There are no technical bottlenecks in the scale-up process from laboratory pilot to industrial production. It is highly adaptable and can flexibly adjust the production scale according to market demand (from gram-level preparation in the laboratory to ton-level production in the industrial sector). No waste liquid or waste residue is generated during the production process, which meets the requirements of green chemical production.

[0020] 5) Green, safe and environmentally friendly, in line with industrial development direction: The reaction process of this invention produces no waste liquid or waste residue, and the tail gas is treated by activated carbon adsorption and discharged in compliance with standards, without secondary pollution; the device is equipped with a CO gas alarm system, safety valve, flame arrester and other safety facilities, and there are no harsh conditions such as extreme high pressure and high temperature throughout the process, so the operation safety risk is low and meets the safety requirements of industrial production; at the same time, the raw material utilization rate is high and the product loss rate is low, which further reduces production costs and environmental burden. Attached Figure Description

[0021] Figure 1 For the present invention 13 High-abundance CO was prepared by CuO catalytic oxidation. 13 A schematic diagram of a CO2 device, where 1 represents... 13 1. CO feed gas cylinder; 2. Mass flow controller; 3. Fixed bed reactor; 4. Heater; 5. Precooler; 6. Refrigeration unit; 7. Collection cylinder; 8. Activated carbon adsorption tank; 9. CO online analyzer; 10. Two-stage oil rotary vane vacuum pump; 11. Nitrogen cylinder; 12. Booster; 13. Low-pressure buffer tank; 14. Temperature sensor; 15. Pressure sensor; 16. Safety alarm device; 17. High-pressure buffer tank; 18. High-pressure filter; 19. Series cylinders; 20. Vent port. Detailed Implementation

[0022] This invention provides 13 High-abundance CO was prepared by CuO catalytic oxidation. 13 The CO2 device is an integrated device, which includes a feed gas supply unit, a fixed bed reaction unit, a cryogenic collection unit, a partial pressure purification unit, and a tail gas treatment unit connected in series. The fixed-bed reaction unit includes a fixed-bed reactor, a heater, and a temperature sensor.

[0023] In this invention, the raw material gas supply unit preferably includes 13The CO feed gas cylinder, mass flow controller, and gas pretreatment module are included. The cryogenic collection unit preferably includes a coil-type precooler, a refrigerator, and a pressure-resistant collection cylinder. The partial pressure purification unit preferably includes a series cylinder, a precision valve group, and a pressure sensor. The exhaust gas treatment unit preferably includes an activated carbon adsorption tank, an online CO analyzer, a vent, and a safety alarm device.

[0024] In this invention, each unit is connected in series through corrosion-resistant and highly airtight pipes to ensure that the entire device is leak-free; the low-pressure buffer tank is above the chiller, the high-pressure buffer tank is to the left of the chiller, and the series-connected steel cylinders are above the adsorption tank.

[0025] The present invention also provides 13 High-abundance CO was prepared by CuO catalytic oxidation. 13 The CO2 method includes the following steps: 1) Pretreatment of the apparatus: High-purity nitrogen gas is used to treat the apparatus. 13 High-abundance CO was prepared by CuO catalytic oxidation. 13 The CO2 device undergoes segmented purging and vacuuming. 2) Constructing the catalytic system: The fixed-bed reactor is sequentially filled with quartz wool, a first layer of quartz sand, CuO catalyst particles, and a second layer of quartz sand. The fixed-bed reactor is preheated to the reaction temperature and then kept at that temperature. 3) Directed catalytic oxidation reaction: 13 CO feed gas is continuously fed into the preheated fixed-bed reactor. 13 CO undergoes a directed oxidation reaction with a CuO catalyst bed to produce... 13 CO2 products; 4) Low-temperature capture and deep purification: 13 The CO2 products were sequentially subjected to cooling pretreatment, low-temperature condensation and collection, and multi-stage partial pressure deep purification to obtain high-abundance CO2. 13 CO2; 5) Harmless treatment of exhaust gas: The exhaust gas in the reaction process is purified by adsorption using modified activated carbon to obtain the adsorbed exhaust gas.

[0026] In this invention, the purity of the high-purity nitrogen gas in step 1) is preferably ≥99.99%, the pressure of the segmented purging is preferably 0.4~0.6MPa, more preferably 0.45~0.55MPa, and even more preferably 0.5MPa, the purging time is preferably 10~20min, more preferably 12~18min, and even more preferably 15~16min, the purging rate is preferably 50~100mL / min, more preferably 60~90mL / min, and even more preferably 70~80mL / min; the vacuuming rate is preferably ≥10L / min, more preferably ≥12L / min, and even more preferably ≥14L / min, and the vacuuming is preferably to a vacuum degree ≤30 mTorr, and even more preferably ≤25 mTorr.

[0027] In this invention, high-purity nitrogen is used to purge and replace the entire device in stages. During the purging process, the gas flow rate is controlled to be uniform to ensure that impurities in the pipelines and each unit are completely removed. Then, a two-stage oil rotary vane vacuum pump is started to evacuate the entire device to below 30 mTorr. The vacuum pump and related valves are then closed, and the device is kept in a vacuum state for 30 minutes to confirm that there are no leaks before proceeding to the next step. This process thoroughly removes residual air, moisture, and other impurities from the system to avoid adverse interference with the reaction process, product quality, and catalyst activity.

[0028] In this invention, in step 2), the thickness of the first layer of quartz sand is preferably 50-100 mm, more preferably 60-90 mm, and even more preferably 70-80 mm; the height of the CuO catalyst particles is preferably 500-700 mm, more preferably 550-650 mm, and even more preferably 600 mm; the thickness of the second layer of quartz sand is preferably 50-100 mm, more preferably 60-90 mm, and even more preferably 70-80 mm; the particle size of the CuO catalyst particles is preferably 0.5-2.0 mm, more preferably 1.0-1.5 mm, and the specific surface area is preferably ≥10 m². 2 / g, further optimized to ≥12m 2 / g, the CuO catalyst particles are preferably calcined and modified CuO catalyst particles, the calcination temperature is preferably 500~600℃, more preferably 520~580℃, more preferably 550~560℃, and the calcination time is preferably 2~4h, more preferably 3h.

[0029] In this invention, the thickness of the quartz wool is preferably 3-6 cm, and more preferably 4-5 cm.

[0030] In this invention, the calcined and modified CuO catalyst particles possess excellent catalytic activity, structural stability, and resistance to deactivation, with a service life ≥500 hours, enabling multiple reuses and further reducing preparation costs. Compared with existing Pt / C and Pd / Al2O3 catalysts, the CuO catalyst is not only lower in cost but also... 13 The CO oxidation reaction has higher selectivity and can effectively avoid side reactions.

[0031] In this invention, the fixed-bed reactor in step 2) preferably adopts an isothermal structure, with a temperature control segment number preferably ≥4, more preferably ≥6, and a temperature control accuracy of ±3℃. The inner diameter of the fixed-bed reactor is preferably 30~50mm, more preferably 35~45mm, and even more preferably 40mm. The design temperature of the fixed-bed reactor is ≤800℃, and the design pressure range is preferably -0.1~1.6MPa. The material is 316L stainless steel, which has good corrosion resistance, sealing and pressure resistance, and can meet the needs of long-term industrial production. The inner wall of the isothermal fixed-bed reactor is polished (surface roughness Ra≤0.8μm) to reduce the adsorption and residue of products on the reactor wall and reduce the product loss rate. The reaction temperature is preferably 300~600℃, more preferably 350~550℃, and even more preferably 400~500℃. The holding time is preferably 30~60min, more preferably 35~55min, and even more preferably 40~50min.

[0032] In this invention, quartz wool is laid at the bottom of the fixed-bed reactor to prevent the loss of catalyst particles and the loosening of the bed caused by airflow impact. A first layer of quartz sand is laid on top of the quartz wool as a support layer, a CuO catalyst particle layer is laid on top of the first layer of quartz sand, and a second layer of quartz sand is laid on top of the CuO catalyst particle layer as a covering layer, forming a composite bed structure of "quartz wool-quartz sand-catalyst-quartz sand". This structure can effectively disperse the raw material airflow, avoid insufficient gas-solid contact caused by excessive local airflow, and prevent the loss of catalyst particles. The thickness of the first layer of quartz sand (support layer) and the second layer of quartz sand (covering layer) matches the height of the catalyst bed to ensure uniform gas-solid contact. After filling, the fixed-bed reactor is preheated to 300~600℃ and kept at a constant temperature for 30~60 minutes. Multi-stage temperature control technology ensures uniform temperature distribution in the bed (temperature deviation ≤±3℃), providing a stable reaction environment for the catalytic oxidation reaction and ensuring that the catalyst is in the optimal active state.

[0033] In this invention, step 3) is described 13 The preferred flow rate of the CO feed gas is 10-50 mL / min, more preferably 20-40 mL / min, and even more preferably 30 mL / min. 13 CO feed gas 13The C abundance is preferably 85~99.99 atomic%, and more preferably 88~95 atomic%. 13 The purity of the CO feed gas is preferably ≥98%, and more preferably ≥98.5%; The preferred temperature for the directional oxidation reaction is 300-600℃, more preferably 400-550℃, and even more preferably 450-500℃; the preferred pressure is 0.1-0.3MPa, more preferably 0.15-0.25MPa, and even more preferably 0.2MPa; and the preferred time is 3-8h, more preferably 4-7h, and even more preferably 5-6h.

[0034] The directional oxidation reaction temperature of the present invention can ensure 13 Complete CO oxidation (conversion rate ≥99.9%), while effectively avoiding isotope fractionation effects caused by excessively high temperatures, ensuring... 13 C abundance recovery rate ≥99%; 13 The optimal matching of CO feed gas flow rate with catalytic bed height and reactor inner diameter ensures sufficient contact between the gas and solid phases, significantly improving reaction conversion and product selectivity while reducing unreacted gas. 13 CO residue; the pressure range of the directional oxidation reaction can balance the reaction rate and product separation efficiency. Too high a pressure will increase the difficulty of product separation, while too low a pressure will reduce the reaction rate.

[0035] In this invention, 13 CO feed gas is continuously fed into a preheated fixed-bed reactor after precise flow control via a mass flow controller. 13 The CO feed gas is preferably industrial-grade or reagent-grade, requiring no additional pretreatment, effectively reducing preparation costs and avoiding isotope abundance loss during pretreatment. A back pressure valve stabilizes the system pressure at 0.1~0.3MPa, with pressure fluctuations ≤±0.01MPa, ensuring reaction stability and product selectivity at a preset temperature (300~600℃). 13 CO undergoes a directed oxidation reaction with CuO in the catalyst bed to produce... 13 The reaction mechanism of CO2 follows the following reaction equation: CO + CuO → CO2 + Cu (where...) 13 The C-labeled reactants and products follow the same reaction mechanism to ensure stable isotope abundance. During the reaction, the system temperature and pressure are monitored in real time by temperature and pressure sensors, and the feed gas flow rate is adjusted in real time by a mass flow controller to ensure stable reaction. The reaction duration is reasonably controlled according to the collection cylinder volume and feed gas flow rate (preferably 3-8 hours).

[0036] In this invention, the temperature for cryogenic condensation collection in step 4) is preferably -100~-80℃, more preferably -95~-85℃, and even more preferably -90℃. Cryogenic condensation collection uses a collection cylinder with a volume preferably 0.5~2.0L, more preferably 1.0~1.5L. The cylinder is preferably made of 316L stainless steel and has a pressure resistance preferably ≥4.0MPa, more preferably ≥4.5MPa. The cylinder opening is sealed with a gasket to ensure no leakage. The efficiency of cryogenic condensation collection is preferably ≥98%. The preferred process for multi-stage partial pressure deep purification is as follows: low-temperature condensation and collection of... 13 CO2 is transferred between two series-connected cylinders through partial pressure transfer, and the operation is repeated 2 to 3 times. The partial pressure is preferably 0.05 to 0.1 MPa, more preferably 0.06 to 0.09 MPa, and even more preferably 0.07 to 0.08 MPa. The partial pressure rate is preferably 5 to 10 mL / min, more preferably 6 to 9 mL / min, and even more preferably 7 to 8 mL / min.

[0037] In this invention, a coil-type precooler is used for cooling pretreatment. The coil-type precooler is made of 316L stainless steel, and the coil diameter is preferably 8~12mm, more preferably 10mm. The cooling medium is industrial cooling water, and the cooling pretreatment temperature is preferably 5~15℃, more preferably 8~12℃, and even more preferably 10℃. The cooling efficiency is preferably ≥90%, more preferably ≥92%. The cooling pretreatment can effectively remove trace amounts of moisture (moisture removal rate ≥95%) and light impurities carried in the product, avoiding the impact of moisture on subsequent product purification and product storage stability. The collection cylinder is placed in the cold trap of the low-temperature refrigeration unit.

[0038] In this invention, after the cryogenic condensation and collection are completed, the raw material gas supply is shut off, and another cylinder connected in series is evacuated to ≤22 mTorr. The connecting valve between the two cylinders is then slowly opened to transfer the pressure. By controlling the rate and number of pressure divisions, trace amounts of residual inert gas impurities (such as nitrogen and argon, with impurity content ≤0.5% after multi-stage pressure division) and unreacted trace amounts of other substances are effectively removed from the product. 13 CO impurities were detected, and the cylinder was finally removed from the cold trap and allowed to warm naturally to room temperature to obtain high abundance. 13 CO2; high abundance 13 The purity of CO2 is preferably ≥99.5% to meet the stringent requirements for high-purity products in fields such as medical diagnostics and high-end organic synthesis.

[0039] In this invention, during the adsorption purification process described in step 5), the space velocity of the exhaust gas is preferably 100~300 h⁻¹. -1 Further preferred is 150~200h -1 The adsorption purification treatment is preferably carried out at room temperature; the exhaust gas contains trace amounts of unreacted substances. 13CO and other exhaust gases produced during the reaction; The modified activated carbon preferably has an adsorption efficiency of ≥99% for CO in the exhaust gas, and more preferably ≥99.5%; the CO concentration in the exhaust gas after adsorption is less than 20 mg / m³. 3 .

[0040] In this invention, modified activated carbon is placed in an activated carbon adsorption tank with a filling amount ≥500g. The modified activated carbon is activated carbon modified with nitric acid. The adsorption capacity of the modified activated carbon for CO is ≥15mg / g. During the adsorption process, the tail gas flow rate and space velocity are controlled. The adsorbed tail gas is detected in real time by an online CO analyzer, and the detection limit is ≤1mg / m³. 3 Ensure that the residual CO concentration in the exhaust gas is below 20 mg / m³ 3 (Occupational exposure limits) are set, and emissions are then discharged through the vent outlet to meet standards, avoiding environmental pollution and safety hazards, and ensuring that exhaust emissions comply with environmental protection standards (GB 16297-1996). The equipment is equipped with a CO gas alarm system, which automatically triggers an alarm and stops emissions when the CO concentration in the exhaust gas exceeds the standard, ensuring production safety and environmental compliance. A flame arrester is installed at the exhaust outlet to prevent backfire hazards and further improve production safety.

[0041] The present invention also provides a method for preparing high abundance 13 CO2, the high abundance 13 The purity of CO2 is preferably ≥99.5%. 13 The preferred C abundance recovery rate is ≥99%, the preferred moisture content is ≤0.1%, and the preferred CO residual concentration is ≤50ppm.

[0042] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0043] In the following examples and comparative examples, the following uses 13 CO feedstock gas was purchased from an isotope technology company; CuO catalyst particles were obtained by calcination at 550℃ for 3 hours; all equipment used was conventional industrial equipment and could be purchased through commercial channels; product purity, 13 C abundance, moisture content, and CO residue concentration were all tested by a testing institution, and the testing methods complied with relevant industry standards.

[0044] The preparation method of nitric acid modified activated carbon is as follows: coal-based activated carbon with a particle size of 3 mm is washed with deionized water and dried at 108℃. Then, it is impregnated with a 12% nitric acid solution at a solid-liquid ratio of 1:3 at room temperature for 5 hours. After washing until neutral, it is dried at 110℃ and then activated under vacuum at 150℃ and 20kPa to obtain nitric acid modified activated carbon.

[0045] Example 1

[0046] (1) Assembly and pretreatment of the device: Build an integrated preparation device and connect it in sequence. 13 The CO feed gas cylinder, mass flow controller, isothermal fixed-bed reactor (40mm inner diameter), coil precooler, refrigerator, collection cylinder (pressure resistant type), activated carbon adsorption tank, and vent are all connected in series via 316L stainless steel pipes. Each unit is equipped with temperature sensors, pressure sensors, and safety alarm devices. The entire system is purged in stages using 99.99% pure nitrogen at a pressure of 0.5MPa, a purging rate of 80mL / min, and a purging time of 15min. A two-stage oil-cooled rotary vane vacuum pump is started at a vacuum rate of 15L / min to evacuate the system to 25 mTorr. The vacuum pump and related valves are then closed, and the system is kept under vacuum for 30min to confirm no leaks.

[0047] (2) Construction of the catalytic system: The inner wall of the isothermal fixed-bed reactor (with 4 temperature control sections) was polished (Ra=0.6μm); the bottom of the reactor was filled with quartz wool (4cm thick), and an 80mm thick layer of quartz sand was laid on top. CuO catalytic particles with a particle size of 0.8~1.2mm were then packed on top of the quartz sand as the catalytic bed (the specific surface area of ​​CuO particles is 12m²). 2 / g), the catalytic bed height is 600mm, and the top is covered with 80mm thick quartz sand; start the heater to preheat the catalytic bed to 500℃, keep the temperature constant for 45min, and ensure the bed temperature is uniform through 4-stage temperature control with a temperature control accuracy of ±3℃.

[0048] (3) Directed catalytic oxidation reaction: The mass flow controller is used to... 13 CO raw material gas ( 13 A flow rate of 92.5 atomic percent carbon (98.5% purity) was continuously introduced into the preheated fixed-bed reactor at 25 mL / min. The pressure of the device was stabilized at 0.2 MPa using a back pressure valve, with a pressure fluctuation range of ≤ ±0.01 MPa. 13 CO undergoes a directional oxidation reaction in full contact with the CuO catalytic bed, and the reaction lasts for 4 hours, producing... 13 CO2 products.

[0049] (4) Low-temperature capture and deep purification: 13 The CO2 product is cooled to 10°C in a coil-type precooler (coil diameter 10mm, cooling medium is industrial cooling water), with a cooling efficiency of 92%, removing trace amounts of moisture (moisture removal rate 96%). It is then passed through a 0.5L collection cylinder (V-350A) placed in a -90°C cold trap for low-temperature condensation and collection for 4 hours, with a collection efficiency of 98.5%. After the low-temperature condensation and collection is completed, the system is shut off. 13A CO feedstock cylinder was connected in series with a collection cylinder (using pressure balancing after liquid methane vaporization). Another empty cylinder (V-350B) was evacuated to 20 mTorr. The connecting valve between the two cylinders was slowly opened to transfer pressure between them, controlling the partial pressure rate at 8 mL / min and the partial pressure at 0.06 MPa. This multi-stage pressure transfer was repeated three times. The V-350A cylinder was then removed from the cold trap and allowed to naturally warm to room temperature, yielding a high-abundance CO feedstock cylinder. 13 CO2.

[0050] (5) Harmless treatment of exhaust gas: The reaction exhaust gas is passed into an activated carbon adsorption tank (500g of nitric acid modified activated carbon is used, and the adsorption efficiency of CO in the exhaust gas is 99.2%). The adsorption process is carried out at room temperature and the space velocity is 200h. -1 The exhaust gas after adsorption was detected by an online CO analyzer, and the CO concentration was 8 mg / m³. 3 After meeting emission requirements, emissions are released through the vent.

[0051] Testing revealed that the high abundance obtained in this embodiment... 13 The purity of CO2 is 99.7%. 13 The abundance of C was 92.3%. 13 The C abundance recovery rate was 99.8%, the moisture content was 0.08%, and the CO residue concentration was 35 ppm. All indicators met the requirements of high-end applications.

[0052] Example 2

[0053] (1) Assembly and pretreatment of the device: The device was purged in stages with high-purity nitrogen gas of 99.99% purity. The purging pressure was 0.6 MPa, the purging rate was 100 mL / min, and the purging time was 12 min. The two-stage oil rotary vane vacuum pump was started and the vacuum rate was 12 L / min. The device was evacuated to 28 mTorr. The vacuum pump and related valves were closed and the device was kept in a vacuum state for 30 min to confirm that there was no leakage.

[0054] (2) Construction of the catalytic system: The bottom of the isothermal fixed-bed reactor is filled with quartz wool (5 cm thick), and a 70 mm thick layer of quartz sand is laid on top. CuO catalytic particles with a particle size of 1.0~1.5 mm are then packed on top of the quartz sand as the catalytic bed (the specific surface area of ​​CuO particles is 11 m²). 2 / g), the catalytic bed height is 550mm, and the top is covered with 70mm thick quartz sand; start the heater to preheat the catalytic bed to 480℃, keep the temperature constant for 40min, and the temperature control accuracy is ±3℃.

[0055] (3) Directed catalytic oxidation reaction: The mass flow controller is used to... 13 CO raw material gas ( 13The flow rate of the preheated fixed-bed reactor was controlled at 22 mL / min. The pressure of the device was stabilized at 0.18 MPa by the back pressure valve, with a pressure fluctuation range of ≤ ±0.01 MPa. The directional oxidation reaction lasted for 5 h.

[0056] (4) Low-temperature capture and deep purification: 13 The CO2 product is cooled to 8°C by a coil-type precooler with a cooling efficiency of 93%, and then passed into a 1.0L collection cylinder (V-350A) placed in a -85°C cold trap; the process is completed after cryogenic condensation and collection. 13 For CO feed gas cylinders, another empty cylinder V-350B connected in series is evacuated to 22 mTorr, and the partial pressure rate is controlled at 6 mL / min. This multi-stage pressure reduction operation is performed twice. Then, V-350A is removed from the cold trap and allowed to naturally warm to room temperature.

[0057] (5) Harmless treatment of exhaust gas: After the reaction exhaust gas is treated by an activated carbon adsorption tank, the CO concentration is detected by an online CO analyzer to be 5 mg / m³. 3 Discharges are made in compliance with standards through the vent outlet.

[0058] Other process conditions are the same as in Example 1.

[0059] Testing revealed that the high abundance obtained in this embodiment... 13 The purity of CO2 is 99.8%. 13 The abundance of C was 98.9%. 13 The carbon abundance recovery rate was 99.9%, the moisture content was 0.05%, and the residual CO concentration was 28 ppm. The product quality is superior to existing processes and meets the requirements. 13 High-end demands such as C-labeled drug synthesis.

[0060] Example 3

[0061] (1) Assembly and pretreatment of the device: The device was purged in stages with high-purity nitrogen gas of 99.99% purity at a purging pressure of 0.45 MPa, a purging rate of 60 mL / min, and a purging time of 18 min. The two-stage oil rotary vane vacuum pump was started at a vacuum rate of 18 L / min and the system was evacuated to 23 mTorr. The vacuum pump and related valves were then closed and the device was kept in a vacuum state for 30 min to confirm that there was no leakage.

[0062] (2) Construction of the catalytic system: The bottom of the isothermal fixed-bed reactor is filled with quartz wool (thickness of 3cm), and a 90mm thick layer of quartz sand is laid on top. CuO catalytic particles with a particle size of 0.5~1.0mm are then packed on top of the quartz sand as the catalytic bed (the specific surface area of ​​CuO particles is 13m²). 2 / g), the catalytic bed height is 650mm, and the top is covered with 90mm thick quartz sand; start the heater to preheat the catalytic bed to 520℃, keep the temperature constant for 50min, and the temperature control accuracy is ±3℃.

[0063] (3) Directed catalytic oxidation reaction: The mass flow controller is used to... 13 CO raw material gas ( 13 The flow rate of the preheated fixed-bed reactor was controlled at 28 mL / min. The system pressure was stabilized at 0.22 MPa by the back pressure valve, with a pressure fluctuation range of ≤ ±0.01 MPa. The directional oxidation reaction lasted for 3.5 h.

[0064] (4) Low-temperature capture and deep purification: 13 The CO2 product is cooled to 12°C by a coil-type precooler with a cooling efficiency of 91%, and then passed into a 0.5L collection cylinder (V-350A) placed in a -95°C cold trap; the process is completed after cryogenic condensation and collection. 13 For CO feed gas cylinders, another empty cylinder V-350B connected in series is evacuated to 18 mTorr, and the partial pressure rate is controlled at 10 mL / min. This multi-stage pressure reduction operation is performed 3 times. Then, V-350A is removed from the cold trap and allowed to naturally warm to room temperature.

[0065] (5) Harmless treatment of exhaust gas: After the reaction exhaust gas is treated by an activated carbon adsorption tank, the CO concentration is detected by an online CO analyzer to be 10 mg / m³. 3 Discharges are made in compliance with standards through the vent outlet.

[0066] Other process conditions are the same as in Example 1.

[0067] Testing revealed that the high abundance obtained in this embodiment... 13 The purity of CO2 is 99.6%. 13 The abundance of C was 88.4%. 13 The C abundance recovery rate was 99.7%, the moisture content was 0.07%, and the CO residue concentration was 42 ppm. All indicators met the design requirements and can meet the needs of environmental monitoring and other fields.

[0068] Example 4

[0069] (1) Assembly and pretreatment of the device: The device was purged in stages with high-purity nitrogen of 99.99% purity at a purging pressure of 0.4 MPa, a purging rate of 50 mL / min, and a purging time of 20 min. The two-stage oil rotary vane vacuum pump was started at a vacuum rate of 10 L / min and the system was evacuated to 30 mTorr. The vacuum pump and related valves were then closed and the device was kept in a vacuum state for 30 min to confirm that there was no leakage.

[0070] (2) Construction of the catalytic system: The inner diameter of the isothermal fixed-bed reactor is 30 mm. The bottom is filled with quartz wool (6 cm thick), and a 50 mm thick layer of quartz sand is laid on top. CuO catalytic particles with a particle size of 0.5~1.0 mm are packed on top of the quartz sand as the catalytic bed (the specific surface area of ​​CuO particles is 10 m²). 2 / g), the catalytic bed height is 500mm, and the top is covered with 50mm thick quartz sand; start the heater to preheat the catalytic bed to 300℃, keep the temperature constant for 60min, and the temperature control accuracy is ±3℃.

[0071] (3) Directed catalytic oxidation reaction: The mass flow controller is used to... 13 CO raw material gas ( 13 The flow rate of the preheated fixed-bed reactor was controlled at 10 mL / min. The pressure of the device was stabilized at 0.1 MPa by the back pressure valve, with a pressure fluctuation range of ≤ ±0.01 MPa. The directional oxidation reaction lasted for 8 hours.

[0072] (4) Low-temperature capture and deep purification: 13 The CO2 product is cooled to 5°C by a coil-type precooler with a cooling efficiency of 90%, and then passed through a system placed at -80°C. 13 The 0.5L collection cylinder (V-350A) in the C cold trap; shut off after cryogenic condensation collection is complete. 13 For CO feed gas cylinders, another empty cylinder V-350B connected in series is evacuated to 20 mTorr, and the partial pressure rate is controlled at 5 mL / min. This multi-stage pressure reduction operation is performed 3 times. Then, V-350A is removed from the cold trap and allowed to naturally warm to room temperature.

[0073] (5) Harmless treatment of exhaust gas: After the reaction exhaust gas is treated by an activated carbon adsorption tank, the CO concentration is detected by an online CO analyzer to be 18 mg / m³. 3 Discharges are made in compliance with standards through the vent outlet.

[0074] Other process conditions are the same as in Example 1.

[0075] Testing revealed that the high abundance obtained in this embodiment... 13 The purity of CO2 is 99.5%. 13 The abundance of C was 89.8%. 13 The carbon abundance recovery rate was 99.8%, the moisture content was 0.09%, and the residual CO concentration was 48 ppm. This invention achieves efficient conversion and high-purity product preparation even at low reaction temperatures, demonstrating the strong adaptability of the method.

[0076] Example 5

[0077] (1) Assembly and pretreatment of the device: The device was purged in stages with high-purity nitrogen gas of 99.99% purity. The purging pressure was 0.6 MPa, the purging rate was 90 mL / min, and the purging time was 10 min. The two-stage oil rotary vane vacuum pump was started and the vacuum rate was 16 L / min. The system was evacuated to 26 mTorr. The vacuum pump and related valves were closed and the device was kept in a vacuum state for 30 min to confirm that there was no leakage.

[0078] (2) Construction of the catalytic system: The inner diameter of the isothermal fixed-bed reactor is 50 mm. The bottom is filled with quartz wool (4 cm thick), and a 100 mm thick layer of quartz sand is laid on top. CuO catalytic particles with a particle size of 1.5~2.0 mm are packed on top of the quartz sand as the catalytic bed (the specific surface area of ​​CuO particles is 11 m²). 2 / g), the catalytic bed height is 700mm, and the top is covered with 100mm thick quartz sand; start the heater to preheat the catalytic bed to 600℃, keep the temperature constant for 30min, and the temperature control accuracy is ±3℃.

[0079] (3) Directed catalytic oxidation reaction: The mass flow controller is used to... 13 CO raw material gas ( 13 The flow rate of the preheated fixed-bed reactor was controlled at 50 mL / min. The pressure of the device was stabilized at 0.3 MPa by the back pressure valve, with a pressure fluctuation range of ≤ ±0.01 MPa. The directional oxidation reaction lasted for 3 hours.

[0080] (4) Low-temperature capture and deep purification: 13 The CO2 product is precooled to 15°C with a cooling efficiency of 92%, and then passed into a 2.0L collection cylinder (V-350A) placed in a -100°C cold trap; the process is then completed by closing the cylinder. 13 For CO feed gas cylinders, another empty cylinder V-350B connected in series is evacuated to 20 mTorr, and the partial pressure rate is controlled at 9 mL / min. This multi-stage pressure reduction operation is performed twice. Then, V-350A is removed from the cold trap and allowed to naturally warm to room temperature.

[0081] (5) Harmless treatment of exhaust gas: After the reaction exhaust gas is treated by an activated carbon adsorption tank, the CO concentration is detected by an online CO analyzer to be 12 mg / m³. 3 Discharges are made in compliance with standards through the vent outlet.

[0082] Other process conditions are the same as in Example 1.

[0083] Testing revealed that the high abundance obtained in this embodiment... 13 The purity of CO2 is 99.6%. 13 The abundance of C was 94.9%. 13The carbon abundance recovery rate was 99.9%, the moisture content was 0.06%, and the residual CO concentration was 38 ppm. This invention maintains excellent reaction performance and product quality even under high reaction pressure, further demonstrating the stability and reliability of the method.

[0084] Comparative Example 1

[0085] This comparative example was prepared using existing Pt / C catalysts and conventional catalytic oxidation processes. 13 The specific operating procedures and parameters for CO2 are as follows: (1) Assembly and pretreatment of the apparatus: a conventional preparation apparatus was set up, without an integrated design, and each unit was connected independently; a high-purity nitrogen purging device was used, with a purging pressure of 0.5 MPa, a purging rate of 80 mL / min, and a purging time of 15 min; the vacuum was evacuated to 50 mTorr and the vacuum pump was turned off.

[0086] (2) Construction of the catalytic system: The fixed bed reactor is a single-stage temperature control reactor, filled with Pt / C catalyst (particle size 0.5~2.0mm), with a catalytic bed height of 600mm; preheated to 500℃, kept at constant temperature for 45min, with a temperature control accuracy of ±5℃.

[0087] (3) Catalytic oxidation reaction: 13 CO raw material gas ( 13 The C abundance was 92.5 atomic%, and the purity was 98.5%. The flow rate was controlled at 25 mL / min and continuously fed into the reactor. The system pressure was stabilized at 0.2 MPa, and the reaction lasted for 4 hours.

[0088] (4) Collection and purification: The reaction product was directly passed into a -90℃ cold trap for collection without pre-cooling dehydration and multi-stage partial pressure purification; the product was obtained after natural rewarming.

[0089] (5) Exhaust gas treatment: The exhaust gas is discharged after being adsorbed by ordinary activated carbon.

[0090] According to the test results, the comparative example obtained... 13 The CO2 product has a purity of 98.2%. 13 The abundance of C was 90.1%. 13 The C abundance recovery rate was 97.4%, the moisture content was 0.25%, and the CO residual concentration was 120 ppm. The quality of the product in this comparative example was significantly lower than that in Example 1, and the catalyst cost was 2.5 times that of the present invention, proving that the method of the present invention has significant advantages in terms of product quality and cost control.

[0091] For the preparation of existing catalytic oxidation methods 13 Products containing CO2 have low purity. 13This invention addresses technical bottlenecks such as severe carbon isotope abundance loss, system leakage and contamination, and difficulties in product separation. Through innovative design of the fixed-bed reactor structure, targeted optimization of the catalytic system, and precise control of reaction parameters, it achieves... 13 CO 13 Highly efficient and targeted conversion of CO2; simultaneously constructing an integrated process system of "system pretreatment - catalytic oxidation reaction - low-temperature condensation and collection - multi-stage partial pressure purification" to significantly improve product purity and... 13 C abundance recovery rate, ensuring target product 13 CO2 purity ≥ 99.5%, 13 C abundance recovery rate ≥99%, indicating high abundance. 13 The large-scale, green production of CO2 provides a completely new technological pathway, filling the gaps in existing technologies for high purity and high abundance. 13 This invention fills a technological gap in CO2 production. The method described in this invention can be widely applied to high-abundance... 13 The laboratory-scale, pilot-scale, and industrial-scale production of CO2 provides applications for medical diagnostics (such as the preparation of non-invasive Helicobacter pylori detection reagents), isotope tracing (such as carbon cycle research), environmental monitoring, and high-end organic synthesis (such as...). 13 It provides high-purity and high-abundance core raw material support for fields such as C-labeled drug molecule synthesis, and has broad academic research value and industrial application prospects.

[0092] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A kind 13 High-abundance CO was prepared by CuO catalytic oxidation. 13 A device for producing CO2, characterized in that, The device is an integrated device, which includes a raw material gas supply unit, a fixed bed reaction unit, a low temperature collection unit, a partial pressure purification unit and a tail gas treatment unit connected in series. The fixed-bed reaction unit includes a fixed-bed reactor, a heater, and a temperature sensor.

2. The apparatus according to claim 1, characterized in that, The raw gas supply unit includes 13 The system includes a CO feed gas cylinder, a mass flow controller, and a gas pretreatment module; a cryogenic collection unit comprising a coil-type precooler, a refrigeration unit, and a collection cylinder; a partial pressure purification unit comprising series cylinders, a precision valve assembly, and a pressure sensor; and a tail gas treatment unit comprising an activated carbon adsorption tank, an online CO analyzer, a vent, and a safety alarm device.

3. A kind 13 High-abundance CO was prepared by CuO catalytic oxidation. 13 The method for CO2 is characterized by, It includes the following steps: 1) Pretreatment of the apparatus: High-purity nitrogen gas is used to treat the apparatus described in claim 1 or 2. 13 High-abundance CO was prepared by CuO catalytic oxidation. 13 The CO2 device undergoes segmented purging and vacuuming. 2) Constructing the catalytic system: The fixed-bed reactor is sequentially filled with quartz wool, a first layer of quartz sand, CuO catalyst particles, and a second layer of quartz sand. The fixed-bed reactor is preheated to the reaction temperature and then kept at that temperature. 3) Directed catalytic oxidation reaction: 13 CO feed gas is continuously fed into the preheated fixed-bed reactor. 13 CO undergoes a directed oxidation reaction with a CuO catalyst bed to produce... 13 CO2 products; 4) Low-temperature capture and deep purification: 13 The CO2 products were sequentially subjected to cooling pretreatment, low-temperature condensation and collection, and multi-stage partial pressure deep purification to obtain high-abundance CO2. 13 CO2; 5) Harmless treatment of exhaust gas: The exhaust gas in the reaction process is purified by adsorption using modified activated carbon to obtain the adsorbed exhaust gas.

4. The method according to claim 3, characterized in that, Step 1) The purity of the high-purity nitrogen gas is ≥99.99%, the pressure of the segmented purging is 0.4~0.6MPa, the time of the segmented purging is 10~20min, the rate of the segmented purging is 50~100mL / min; the vacuuming rate is ≥10L / min, and the vacuum is evacuated to a vacuum degree ≤30 mTorr.

5. The method according to claim 3 or 4, characterized in that, Step 2) The thickness of the first layer of quartz sand is 50~100mm, the height of the CuO catalyst particles is 500~700mm, and the thickness of the second layer of quartz sand is 50~100mm; the particle size of the CuO catalyst particles is 0.5~2.0mm, and the specific surface area is ≥10m². 2 / g, the CuO catalyst particles are calcined and modified CuO catalyst particles.

6. The method according to claim 5, characterized in that, Step 2) The fixed-bed reactor adopts an isothermal structure with ≥4 temperature control sections and a temperature control accuracy of ±3℃. The inner diameter of the fixed-bed reactor is 30~50mm; the reaction temperature is 300~600℃; and the holding time is 30~60min.

7. The method according to claim 5, characterized in that, Step 3) 13 The flow rate of the CO feed gas is 10~50 mL / min. 13 CO feed gas 13 The C abundance is 85–99.99 atomic%. 13 The purity of the CO feed gas is ≥98%; The directional oxidation reaction is carried out at a temperature of 300~600℃, a pressure of 0.1~0.3MPa, and a time of 3~8h.

8. The method according to claim 6 or 7, characterized in that, Step 4) The temperature for the cryogenic condensation collection is -100~-80℃. The cryogenic condensation collection uses a collection cylinder with a volume of 0.5~2.0L, made of 316L stainless steel, and with a pressure resistance of ≥4.0MPa. The specific process of multi-stage partial pressure deep purification is as follows: the low-temperature condensed and captured... 13 CO2 is transferred between two series-connected cylinders through a pressure reduction process, which is repeated 2 to 3 times, with a pressure reduction of 0.05 to 0.1 MPa.

9. The method according to claim 8, characterized in that, In step 5), during the adsorption purification process, the space velocity of the exhaust gas is 100~300 h⁻¹. -1 The adsorption purification process is carried out at room temperature; the exhaust gas contains trace amounts of unreacted substances. 13 CO and other exhaust gases produced during the reaction; The modified activated carbon has an adsorption efficiency of ≥99% for CO in exhaust gas; the CO concentration in the exhaust gas after adsorption is less than 20 mg / m³. 3 .

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