Device and method for preparing oxygen isotope labeled carbon monoxide and carbon dioxide

Abstract

The invention belongs to the field of oxygen isotope labeled gas preparation, and specifically discloses a device for preparing oxygen isotope labeled carbon monoxide and carbon dioxide, comprising a first collecting bottle, the first collecting bottle is connected to a reactor, the first collecting bottle is connected to a second collecting bottle, the second collecting bottle is connected to a third collecting bottle, the third collecting bottle is connected to a fourth collecting bottle, the fourth collecting bottle is connected to a CO product gas bag, and further comprises a vacuum pump and a CO 2 The product gas bag, the first collection bottle is placed in the first-stage freezing device, the second collection bottle is placed in the second-stage freezing device, the third collection bottle is placed in the third-stage freezing device, and the fourth collection bottle is placed in the fourth-stage freezing device. The present invention makes CO 2 and CO and H 2 O are collected separately to obtain oxygen isotope-labeled CO 2 At the same time as pure CO, oxygen isotope H was recovered. 2 O.

Description

Technical Field

[0001] The invention belongs to the technical field of preparation of carbon monoxide and carbon dioxide labeled with oxygen isotopes, in particular to a device and a method for preparing carbon monoxide and carbon dioxide labeled with oxygen isotopes. Background Art

[0002] In nature, oxygen 16 O. 17 O. 18 The natural abundances of the three stable isotopes of O are 99.759%, 0.037% and 0.204% respectively. In oxygen isotope products, it is generally required 16 O abundance is above 99.9%, 17 O is above 90%, 18 The abundance of O is above 95%. Due to the difficulty in separating oxygen isotopes, further purification is more difficult when the abundance is high. Therefore, the choice of preparation route is crucial when preparing oxygen isotope markers.

[0003] Oxygen isotope labeled carbon monoxide and carbon dioxide have important uses in scientific research. They can be used as tracers, neutron absorbers, etc. to study the source, path and reaction mechanism of elements, etc. For example, they are used as standard reference gases to study the source of oxygen in plant photosynthesis. Due to the difficulty in preparing oxygen isotope labeled carbon monoxide and carbon dioxide, no domestic manufacturer can prepare them independently. Only a few foreign companies such as CIL and Bayer can produce them. They are generally prepared by burning high-purity carbon in isotopic oxygen. Since the ignition point of pure carbon is very high, it needs to be controlled at a high temperature of more than 1000℃ for combustion. The conditions are harsh and require a lot of cost. In addition, if the temperature cannot reach more than 1000℃, the isotopic oxygen may not fully participate in the combustion, resulting in the disadvantage of low utilization rate of isotopic oxygen. At the same time, during the combustion process, the isotopic oxygen and the combustion products CO2 and CO are mixed together. In the subsequent separation process, due to the similar boiling points of oxygen and CO, separation and purification are difficult, which leads to the high price of such products and a long domestic supply cycle.

[0004] Therefore, it is necessary to develop a relatively simple method for preparing oxygen isotope labeled carbon monoxide and carbon dioxide to reduce production costs and meet the demand for such products in related domestic research fields. Summary of the invention

[0005] Purpose of the invention: To provide an apparatus and method for preparing oxygen isotope-labeled carbon monoxide and carbon dioxide to solve the above-mentioned problems existing in the prior art.

[0006] Technical solution: A device for preparing oxygen isotope-labeled carbon monoxide and carbon dioxide, comprising a first collecting bottle, a second collecting bottle, a third collecting bottle and a fourth collecting bottle;

[0007] The first collecting bottle is connected to the reactor through pipeline 1, the first collecting bottle is connected to the second collecting bottle through tee 1, the second collecting bottle is connected to the third collecting bottle through tee 2, the third collecting bottle is connected to the fourth collecting bottle through tee 3, the fourth collecting bottle is connected to the CO product gas bag through tee 4, the other end of tee 3 is connected to a vacuum pump through tee 5, the third end of tee 5 is connected to a CO2 product gas bag, and the other ends of tee 1, tee 2 and tee 4 are all connected to the vacuum pump.

[0008] The pipeline 1 is provided with a switch valve 1, the pipelines between the tee 1, tee 2, tee 4 and tee 5 and the vacuum pump are all provided with a switch valve 2, the pipeline between the fourth collecting bottle and the tee 4 is provided with a switch valve 3, and the pipeline between the third collecting bottle and the tee 2 is provided with a switch valve 4;

[0009] The first collecting bottle is placed in a first-stage freezing device, the second collecting bottle is placed in a second-stage freezing device, the third collecting bottle is placed in a third-stage freezing device, and the fourth collecting bottle is placed in a fourth-stage freezing device.

[0010] Further: a three-way valve six is ​​provided on the pipeline between the other end of the three-way valve one and the vacuum pump, the other end of the three-way valve six is ​​connected to a buffer air bag, and a switch valve five is provided on the pipeline between the three-way valve six and the vacuum pump.

[0011] Further: the reaction kettle is arranged on a heater with magnetic stirring.

[0012] Further: a switch valve six is ​​provided on the pipeline between the buffer gas bag and the other end of the three-way six, and a switch valve seven is provided on the pipeline between the other end of the three-way five and the CO2 product gas bag.

[0013] The present invention also provides a method for preparing oxygen isotope-labeled carbon monoxide and carbon dioxide using the device for preparing oxygen isotope-labeled carbon monoxide and carbon dioxide, comprising the following steps:

[0014] S1: adding oxygen isotope labeled oxalic acid into the reactor;

[0015] S2: Vacuum the system;

[0016] S3: performing a cooling process on the first collecting bottle, the second collecting bottle, the third collecting bottle and the fourth collecting bottle;

[0017] S4: The reactor is heated by a heater with magnetic stirring to decompose the oxalic acid in the reactor to generate carbon dioxide, carbon monoxide and water. The chemical formula is as follows:

[0018] H2C2O4=CO2↑+CO↑+H2O

[0019] When the material in the reactor is decomposed, stop heating;

[0020] S5: The generated mixed gas passes through the first collecting bottle, the second collecting bottle, the third collecting bottle and the fourth collecting bottle in sequence and then enters the CO product gas bag, and CO gas is obtained in the CO product gas bag, wherein the water vapor in the mixed gas becomes liquid or solid and is retained in the first collecting bottle or the second collecting bottle, and the carbon dioxide in the mixed gas becomes solid and is retained in the third collecting bottle or the fourth collecting bottle;

[0021] S6: removing the first-stage freezing device and the second-stage freezing device, and collecting water in the first collecting bottle and the second collecting bottle;

[0022] S7: Close switch valve three and switch valve four, remove the third-stage refrigeration device and the fourth-stage refrigeration device, reheat the third collection bottle and the fourth collection bottle to room temperature, open switch valve seven, and allow the carbon dioxide gas in the third collection bottle and the fourth collection bottle to enter the CO2 product gas bag.

[0023] Among them: Step S2 is specifically as follows: Step S2 is specifically as follows: open switch valve one, switch valve two, switch valve three, switch valve four, switch valve five, switch valve six and switch valve seven, and evacuate the system by a vacuum pump. When the absolute pressure of the system is less than 5Pa, close switch valve two, switch valve five, switch valve six and switch valve seven.

[0024] Wherein: Step S3 specifically comprises: cooling the first collection bottle by a first-stage freezing device so that the temperature inside the first collection bottle is between -4°C and 0°C, cooling the second collection bottle by a second-stage freezing device so that the temperature inside the second collection bottle is between -20°C and -10°C, cooling the third collection bottle by a third-stage freezing device so that the temperature inside the third collection bottle is between -85°C and -78.5°C, and cooling the fourth collection bottle by a fourth-stage freezing device so that the temperature inside the fourth collection bottle is between -120°C and -100°C.

[0025] Wherein: in step S4, the reactor is heated by a heater with magnetic stirring to make the temperature of the reactor between 189.5°C and 250°C.

[0026] The present invention discloses a device and method for preparing oxygen isotope-labeled carbon monoxide and carbon dioxide, which has the following beneficial effects:

[0027] The abundance of oxygen isotopes prepared by the oxygen isotope exchange method of the present invention is relatively high, and the obtained oxygen isotope-labeled CO2 and CO 16 O abundance is greater than 99.95%, 17 O abundance is greater than 90%,18 O abundance greater than 95%;

[0028] The present invention decomposes oxalic acid by heating, and simultaneously obtains oxygen isotope-labeled CO2, CO and H2O. CO2, CO and H2O are collected separately by different temperatures, and the oxygen isotope H2O is recovered while the product is obtained.

[0029] The preparation method disclosed by the invention has simple preparation process, simple and efficient product separation and purification process, high oxygen isotope utilization rate, no other impurities are generated, and is environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic structural diagram of a device for preparing oxygen isotope-labeled carbon monoxide and carbon dioxide according to the present invention;

[0031] The accompanying drawings are marked as: reactor 1, first collecting bottle 2, second collecting bottle 3, third collecting bottle 4, fourth collecting bottle 5, vacuum pump 6, switch valve three 7, CO product gas bag 8, switch valve one 9, buffer gas bag 10, switch valve five 11, switch valve two 12, CO2 product gas bag 13, switch valve four 14, switch valve six 15, switch valve seven 16. DETAILED DESCRIPTION

[0032] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0033] like Figure 1 As shown, the device for preparing oxygen isotope-labeled carbon monoxide and carbon dioxide comprises a first collecting bottle 2, a second collecting bottle 3, a third collecting bottle 4 and a fourth collecting bottle 5;

[0034] The first collecting bottle 2 is connected to the reactor 1 through the pipeline 1, the first collecting bottle 2 is connected to the second collecting bottle 3 through the tee 1, the second collecting bottle 3 is connected to the third collecting bottle 4 through the tee 2, the third collecting bottle 4 is connected to the fourth collecting bottle 5 through the tee 3, the fourth collecting bottle 5 is connected to the CO2 product gas bag 8 through the tee 4, and the third collecting bottle 4 is connected to the fourth collecting bottle 5 through the tee 3. The two ends of the tee are required to connect the third collecting bottle 4 to the fourth collecting bottle 5, so the third end of the remaining tee 3 is connected to the vacuum pump 6 through the tee 5, and the third end of the tee 5 is also connected to the CO2 product gas bag 13. The third end of the tee 1 and the third end of the tee 2 and the third ends of the three-way four are connected to the vacuum pump 6, the pipeline one is provided with a switch valve one 9, the pipelines between the three-way one, three-way two, three-way four and three-way five and the vacuum pump 6 are provided with switch valve two 12, the pipeline between the fourth collecting bottle 5 and the three-way four is provided with a switch valve three 7, and the pipeline between the third collecting bottle 4 and the three-way two is provided with a switch valve four 14; the first collecting bottle 2 is placed in the first-stage freezing device, the second collecting bottle 3 is placed in the second-stage freezing device, the third collecting bottle 4 is placed in the third-stage freezing device, and the fourth collecting bottle 5 is placed in the fourth-stage freezing device.

[0035] In the previous embodiment, the reactor 1 is used to contain oxalic acid. The oxalic acid in the reactor 1 is decomposed into CO2↑, CO↑, and H2O by heat. When the temperature in the reactor 1 is higher than the boiling point of water, the liquid H2O turns into water vapor, thereby forming a mixed gas of CO2↑, CO↑, and H2O↑ in the reactor 1. When the switch valve 1 9, the switch valve 3 7, and the switch valve 4 14 are opened, and the switch valve 2 12, the switch valve 5 11, the switch valve 6 15, and the switch valve 7 16 are closed, the mixed gas in the reactor 1 passes through the first collection bottle 2 and the second collection bottle 3 in sequence. The first-stage refrigeration device is used to The first collection bottle is frozen, and the second-stage freezing device is used to freeze the second collection bottle. Since the freezing point of water in the mixed gas is the highest, CO2 is the second, and CO is the lowest, therefore, when the temperature of the first collection bottle 2 and the second collection bottle 3 is lowered to between the freezing point of water and the freezing point of CO2, the gaseous water in the first collection bottle 2 and the second collection bottle 3 becomes solid water and is retained in the first collection bottle 2 and the second collection bottle 3, and the remaining CO2↑ and CO↑ continue to move to the third collection bottle 4 and the fourth collection bottle 5. The third-stage freezing device is used to cool the third collection bottle 4, and the fourth-stage cooling device is used to cool the third collection bottle 4. The freezing device is used to cool the fourth collection bottle 5. When the temperature of the third collection bottle 4 and the fourth collection bottle 5 is reduced to between the freezing point of CO2 and the freezing point of CO, the gaseous CO2 becomes solid in the third collection bottle 4 and the fourth collection bottle 5 and is retained in the third collection bottle 4 and the fourth collection bottle 5. The remaining gas is only CO. CO enters the CO product gas bag 8 through the switch valve 3 7. The CO is collected by the CO product gas bag 8. By collecting the water in the first collection bottle 2 and the second collection bottle 3, the oxygen isotope labeled water can be collected. In addition, the third stage freezing is removed. After the third-stage refrigeration device and the fourth-stage refrigeration device are installed, the third collecting bottle 4 and the fourth collecting bottle 5 are gradually heated up to room temperature, and the solid CO2 turns into gaseous CO2 again. Therefore, before removing the third-stage refrigeration device and the fourth-stage refrigeration device, it is necessary to close the switch valve three 7 and the switch valve four 14 to prevent the gaseous CO2 from entering the CO product gas bag 8 or entering the reactor 1. The gaseous CO2 enters the CO2 product gas bag 13 through the switch valve seven 16 and is collected. The vacuum pump 6 is used to vacuum the system before heating the reactor 1 to prevent the air in the system from affecting the purity of the collected CO2 and CO.

[0036] When it is necessary to prepare 18 When CO2 and CO are used 18 O isotope-labeled oxalic acid can be used. 17 When CO2 and CO are used 17 O isotope-labeled oxalic acid can be used. 16 When CO2 and CO are used 16 O isotope-labeled oxalic acid can be used.

[0037] In a specific embodiment: a three-way six is ​​provided on the pipeline between the third end of the three-way one and the vacuum pump 6, a buffer air bag 10 is connected to the third end of the three-way six, a switch valve five 11 is provided on the pipeline between the buffer air bag 10 and the vacuum pump 6, and a switch valve six is ​​provided on the pipeline between the buffer air bag 10 and the third end of the three-way six. The buffer air bag 10 is used to buffer the system. When CO2 and CO increase the air pressure of the system, in order to avoid explosion, the switch valve six 15 can be opened to allow the mixed gas to enter the buffer air bag 10.

[0038] In a specific embodiment, the reactor 1 is arranged on a heater with magnetic stirring, which can conveniently stir and heat the reactor 1 so that the oxalic acid in the reactor 1 is fully decomposed.

[0039] The present invention also discloses a method for preparing oxygen isotope-labeled carbon monoxide and carbon dioxide using an oxygen isotope-labeled carbon monoxide and carbon dioxide preparation device, comprising the following steps:

[0040] S1: Add oxygen isotope labeled oxalic acid into the reactor 1. The oxygen isotope labeled oxalic acid can be H2C2 18 O4、H2C2 16 O4 or H2C2 17 O4;

[0041] S2: evacuate the system; the specific step S2 is: open the switch valve 1, the switch valve 2, the switch valve 3, the switch valve 4, the switch valve 5, the switch valve 6 and the switch valve 7, and evacuate the system by a vacuum pump. When the absolute pressure of the system is less than 5Pa, close the switch valve 2, the switch valve 5, the switch valve 6 and the switch valve 7;

[0042] S3: performing cooling treatment on the first collection bottle 2, the second collection bottle 3, the third collection bottle 4 and the fourth collection bottle 5, specifically, cooling the first collection bottle 2 by a first-stage freezing device so that the temperature inside the first collection bottle is between -4°C and 0°C, cooling the second collection bottle 3 by a second-stage freezing device so that the temperature inside the second collection bottle 3 is between -20°C and -10°C, cooling the third collection bottle 4 by a third-stage freezing device so that the temperature inside the third collection bottle 4 is between -85°C and -78.5°C, and cooling the fourth collection bottle 5 by a fourth-stage freezing device so that the temperature inside the fourth collection bottle 5 is between -120°C and -100°C;

[0043] S4: The reactor 1 is heated by a heater with magnetic stirring, so that the oxalic acid in the reactor 1 undergoes a decomposition reaction to generate carbon dioxide, carbon monoxide and water. The chemical formula is as follows:

[0044] H2C2O4=CO2↑+CO↑+H2O

[0045] When the decomposition of the material in the reactor 1 is completed, the heating is stopped. The reactor 1 is heated by a heater with magnetic stirring, and the temperature of the reactor 1 reaches 189.5°C to 250°C, preferably 190°C to 210°C;

[0046] S5: the generated mixed gas passes through the first collecting bottle 2, the second collecting bottle 3, the third collecting bottle 4 and the fourth collecting bottle 5 in sequence and then enters the CO product gas bag 8, and CO gas is obtained in the CO product gas bag 8, wherein the water vapor in the mixed gas becomes liquid or solid and is retained in the first collecting bottle 2 or the second collecting bottle 3, and the carbon dioxide in the mixed gas becomes solid and is retained in the third collecting bottle 4 or the fourth collecting bottle 5;

[0047] In this step, the temperature in the first collecting bottle is between -4°C and 0°C. When the mixed gas enters the first collecting bottle 2, most of the gaseous water in the first collecting bottle 2 becomes solid water, and the remaining small amount of gaseous water, CO2 and CO enter the second collecting bottle 3. The small amount of gaseous water in the second collecting bottle 3 is completely turned into solid state, and the remaining CO2 and CO enter the third collecting bottle 4. A large amount of CO2 gas is turned into solid state in the third collecting bottle 4. The remaining small amount of CO2 gas and CO enter the fourth collecting bottle 5. The small amount of CO2 gas in the fourth collecting bottle 5 is completely turned into solid state, and the remaining CO gas enters the CO product gas bag 8 from the fourth collecting bottle 5.

[0048] S6: removing the first-stage freezing device and the second-stage freezing device, and collecting water in the first collecting bottle 2 and the second collecting bottle 3;

[0049] S7: Close the switch valve three 7 and the switch valve four 14, remove the third-stage refrigeration device and the fourth-stage refrigeration device, and reheat the third collecting bottle 4 and the fourth collecting bottle 5 to room temperature. After the third collecting bottle 4 and the fourth collecting bottle 5 are reheated, the solid CO2 becomes gaseous again and enters the CO2 product gas bag 13.

[0050] In order to facilitate understanding of the above technical solutions of the present invention, the above technical solutions of the present invention are described in detail below.

[0051] Embodiment 1:

[0052] Pick 18 9.8 g of O-labeled oxalic acid was placed in reactor 1;

[0053] Start the vacuum pump 6 to extract the air in the device so that the absolute pressure in the device is less than 5Pa;

[0054] The first collection bottle 2, the second collection bottle 3, the third collection bottle 4 and the fourth collection bottle 5 are subjected to a cooling treatment, so that the temperature in the first cooling device reaches 0°C, the temperature in the second freezing device reaches -10°C, the temperature in the third freezing device reaches -80°C; and the temperature in the fourth device reaches -100°C;

[0055] The reactor 1 was heated by a heater with magnetic stirring to raise the temperature of the reactor 1 to above 200°C, and the oxalic acid began to decompose and generate gas. The generated gas passed through the first collection bottle 2, the second collection bottle 3, the third collection bottle 4 and the fourth collection bottle 5 in sequence. The gas discharged from the fourth collection bottle 5 was collected in the CO product gas bag 8 to obtain 2.99gC 18 O, yield 99.7%;

[0056] After the oxalic acid in the reactor 1 is decomposed, the heating is stopped; the first-stage refrigeration device and the second-stage refrigeration device are removed, and the liquid in the first collection bottle 2 and the second collection bottle 3 is collected to obtain 1.99g H2 18 O product, yield 99.5%;

[0057] The third and fourth stage refrigeration devices were removed, and the third and fourth collection bottles 4 and 5 were slowly reheated to room temperature. The generated gas was collected in the CO2 product gas bag 13 to obtain 4.79 g CO 18 O2, yield 99.8%.

[0058] Embodiment 2:

[0059] Pick 16 9.0 g of O-labeled oxalic acid was placed in reactor 1;

[0060] Start the vacuum pump 6 to extract the air in the device so that the absolute pressure in the device is less than 5Pa;

[0061] The first collection bottle 2, the second collection bottle 3, the third collection bottle 4 and the fourth collection bottle 5 are subjected to a cooling treatment, so that the temperature in the first cooling device reaches 0°C, the temperature in the second freezing device reaches -10°C, the temperature in the third freezing device reaches -80°C; and the temperature in the fourth device reaches -100°C;

[0062] The reactor 1 was heated by a heater with magnetic stirring to raise the temperature of the reactor 1 to 190°C. Oxalic acid began to decompose and generate gas. The generated gas passed through the first collection bottle 2, the second collection bottle 3, the third collection bottle 4 and the fourth collection bottle 5 in sequence. The gas discharged from the fourth collection bottle 5 was collected in the CO product gas bag 8 to obtain 2.79g C 16 O, yield 99.6%;

[0063] After the oxalic acid in the reactor 1 is decomposed, the heating is stopped; the first-stage refrigeration device and the second-stage refrigeration device are removed, and the liquid in the first collection bottle 2 and the second collection bottle 3 is collected to obtain 1.79gH2 16 O product, yield 99.4%;

[0064] The third and fourth stage refrigeration devices were removed, and the third and fourth collection bottles 4 and 5 were slowly reheated to room temperature. The generated gas was collected in the CO2 product gas bag 13 to obtain 4.39 g CO 16 O2, yield 99.8%.

[0065] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various equivalent transformations can be made to the technical scheme of the present invention, and these equivalent transformations all belong to the protection scope of the present invention.

Claims

1. A device for preparing oxygen isotope-labeled carbon monoxide and carbon dioxide, characterized in that: comprising a first collecting bottle, a second collecting bottle, a third collecting bottle and a fourth collecting bottle; The first collecting bottle is connected to the reactor through pipeline 1, and the reactor is used to contain oxalic acid. The first collecting bottle is connected to the second collecting bottle through tee 1, the second collecting bottle is connected to the third collecting bottle through tee 2, the third collecting bottle is connected to the fourth collecting bottle through tee 3, the fourth collecting bottle is connected to the CO product gas bag through tee 4, the other end of tee 3 is connected to a vacuum pump through tee 5, the other end of tee 5 is connected to a CO2 product gas bag, and the other ends of tee 1, tee 2 and tee 4 are all connected to the vacuum pump. The pipeline 1 is provided with a switch valve 1, the pipelines between the tee 1, tee 2, tee 4 and tee 5 and the vacuum pump are all provided with a switch valve 2, the pipeline between the fourth collecting bottle and the tee 4 is provided with a switch valve 3, and the pipeline between the third collecting bottle and the tee 2 is provided with a switch valve 4; The first collecting bottle is placed in a first-stage freezing device, the second collecting bottle is placed in a second-stage freezing device, the third collecting bottle is placed in a third-stage freezing device, and the fourth collecting bottle is placed in a fourth-stage freezing device.

2. The device for preparing oxygen isotope-labeled carbon monoxide and carbon dioxide according to claim 1, characterized in that: A three-way valve six is ​​provided on the pipeline between the other end of the three-way valve one and the vacuum pump, the other end of the three-way valve six is ​​connected to a buffer air bag, and a switch valve five is provided on the pipeline between the three-way valve six and the vacuum pump.

3. The device for preparing oxygen isotope-labeled carbon monoxide and carbon dioxide according to claim 2, characterized in that: The reaction kettle is arranged on a heater with magnetic stirring.

4. The device for preparing oxygen isotope-labeled carbon monoxide and carbon dioxide according to claim 3, characterized in that: A switch valve 6 is provided on the pipeline between the buffer gas bag and the other end of the three-way valve 6, and a switch valve 7 is provided on the pipeline between the other end of the three-way valve 5 and the CO2 product gas bag.

5. A method for preparing oxygen isotope labeled carbon monoxide and carbon dioxide using the preparation device of claim 4, characterized in that: The steps include: S1: adding oxygen isotope labeled oxalic acid into the reactor; S2: Vacuum the system; S3: performing a cooling process on the first collecting bottle, the second collecting bottle, the third collecting bottle and the fourth collecting bottle; Specifically, the first collection bottle is cooled by a first-stage freezing device so that the temperature inside the first collection bottle is between -4°C and 0°C, the second collection bottle is cooled by a second-stage freezing device so that the temperature inside the second collection bottle is between -20°C and -10°C, the third collection bottle is cooled by a third-stage freezing device so that the temperature inside the third collection bottle is between -85°C and -78.5°C, and the fourth collection bottle is cooled by a fourth-stage freezing device so that the temperature inside the fourth collection bottle is between -120°C and -100°C; S4: The reactor is heated by a heater with magnetic stirring to decompose the oxalic acid in the reactor to generate carbon dioxide, carbon monoxide and water. The chemical formula is as follows: H2C2O4=CO2↑+CO↑+H2O When the material in the reactor is decomposed, stop heating; S5: The generated mixed gas passes through the first collecting bottle, the second collecting bottle, the third collecting bottle and the fourth collecting bottle in sequence and then enters the CO product gas bag, and CO gas is obtained in the CO product gas bag, wherein the water vapor in the mixed gas becomes liquid or solid and is retained in the first collecting bottle or the second collecting bottle, and the carbon dioxide in the mixed gas becomes solid and is retained in the third collecting bottle or the fourth collecting bottle; S6: removing the first-stage freezing device and the second-stage freezing device, and collecting water in the first collecting bottle and the second collecting bottle; S7: Close switch valve three and switch valve four, remove the third-stage refrigeration device and the fourth-stage refrigeration device, reheat the third collection bottle and the fourth collection bottle to room temperature, open switch valve seven, and allow the carbon dioxide gas in the third collection bottle and the fourth collection bottle to enter the CO2 product gas bag.

6. The method for preparing oxygen isotope-labeled carbon monoxide and carbon dioxide according to claim 5, characterized in that: Step S2 is specifically as follows: open switch valve 1, switch valve 2, switch valve 3, switch valve 4, switch valve 5, switch valve 6 and switch valve 7, evacuate the system by means of a vacuum pump, and when the absolute pressure of the system is less than 5 Pa, close switch valve 2, switch valve 5, switch valve 6 and switch valve 7.

7. The method for preparing oxygen isotope-labeled carbon monoxide and carbon dioxide according to claim 5, characterized in that: In step S4, the reactor is heated by a heater with magnetic stirring to keep the temperature of the reactor between 189.5°C and 250°C.

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