Stable isotope mass spectrum system based on reduction reaction

Abstract

The invention discloses a stable isotope mass spectrometry system based on reduction reaction, which is applied to the field of stable isotope mass spectrometry, and is characterized in that a first sample introduction module continuously introduces inert gas into an oxidation module, and the inert gas enters a gas mixing module through the oxidation module; the second sample introduction module introduces to-be-detected gas into the gas mixing module, the to-be-detected gas and the inert gas pass through the reduction module together and are introduced into the stable isotope mass spectrometer, and the isotope ratio of the to-be-detected gas is obtained; the first vacuum module is used for enabling the gas mixing module to be in a vacuum state before the inert gas and the gas to be detected enter the gas mixing module; the second vacuum module is used for enabling the reduction module to be in a vacuum state before the inert gas and the to-be-detected gas enter the reduction module. According to the method, the isotope calibration cost of nitrogen, nitrous oxide, nitric oxide and carbon dioxide is effectively reduced, and the method is suitable for isotope calibration of most laboratories.

Description

Technical Field

[0001] The invention relates to the field of stable isotope mass spectrometry, and in particular to a stable isotope mass spectrometry system based on reduction reaction. Background Art

[0002] In recent years, gas stable isotope mass spectrometers have been widely used in earth science, life science and environmental research. As the current mainstream calibration technology, the dual-path injection system of stable isotope mass spectrometry achieves high-precision calibration of working standard gas by comparing one sample gas injection path with one standard reference gas injection path. However, due to the high price of the dual-path injection system, it has not yet been widely popularized in laboratories, and some laboratories do not have the ability to calibrate this isotope.

[0003] Therefore, how to provide a stable isotope mass spectrometry system based on reduction reaction with low cost and suitable for most laboratories is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0004] In view of this, the present invention proposes a stable isotope mass spectrometry system based on reduction reaction.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A stable isotope mass spectrometry system based on reduction reaction, comprising: an oxidation module, a reduction module, a first sample injection module, a second sample injection module, a gas mixing module, a first vacuum module, a second vacuum module, and a stable isotope mass spectrometer;

[0007] The first injection module continuously introduces inert gas into the oxidation module, and the inert gas enters the gas mixing module through the oxidation module; the second injection module introduces the gas to be tested into the gas mixing module and passes through the reduction module together with the inert gas, and then enters into the stable isotope mass spectrometer to obtain the isotope ratio of the gas to be tested; the first vacuum module is used to make the gas mixing module in a vacuum state before the inert gas and the gas to be tested enter the gas mixing module; the second vacuum module is used to make the reduction module in a vacuum state before the inert gas and the gas to be tested enter the reduction module.

[0008] Optionally, the inert gas is argon.

[0009] Optionally, a polytetrafluoroethylene stopcock is provided at the connection between the gas mixing module and the oxidation module, the second sample injection module, and the reduction module.

[0010] Optionally, the connection between the gas mixing module and the oxidation module, the second sample injection module, and the reduction module is also provided with an internal thread for moving the polytetrafluoroethylene stopcock up and down to control the connection and closure of the connection.

[0011] Optionally, the polytetrafluoroethylene plug is also provided with at least one sealing ring used in conjunction with the polytetrafluoroethylene plug.

[0012] Optionally, the gas to be tested is nitrogen, nitrous oxide, nitric oxide, or carbon dioxide.

[0013] Optionally, the reduction module is filled with active copper particles.

[0014] Optionally, the first vacuum module is used to put the gas mixing module into a vacuum state before the inert gas and the gas to be tested enter the gas mixing module, specifically:

[0015] Before the inert gas and the gas to be tested enter the gas mixing module, the polytetrafluoroethylene stopcock at the connection between the gas mixing module, the oxidation module and the second injection module is controlled to be in a closed state. After the inside of the gas mixing module is vacuum-treated by the first vacuum module, the polytetrafluoroethylene stopcock at the connection between the gas mixing module, the oxidation module and the second injection module is connected.

[0016] Optionally, the second vacuum module is used to put the reduction module in a vacuum state before the inert gas and the gas to be tested enter the reduction module, specifically:

[0017] Before the inert gas and the gas to be tested enter the reduction module, the polytetrafluoroethylene stopcock at the connection between the gas mixing module and the reduction module is controlled to be in a closed state. After the inside of the reduction module is vacuum-treated by the second vacuum module, the polytetrafluoroethylene stopcock at the connection between the gas mixing module and the reduction module is connected.

[0018] Optionally, the first vacuum module and the second vacuum module are both vacuum pumps.

[0019] It can be known from the above technical scheme that compared with the prior art, the present invention proposes a stable isotope mass spectrometry system based on reduction reaction. Different from the expensive price of the existing stable isotope mass spectrometry dual-path system, by reducing the gas to be tested using the hot copper of the reduction module, the isotope accurate calibration of nitrogen, nitrous oxide, nitric oxide, and carbon dioxide with low cost is achieved, and the inert gas argon, which is easier to obtain and has lower cost, is used as a continuous input flow, in conjunction with the first vacuum module and the second vacuum module, so that before the inert gas and the gas to be tested enter the gas mixing module, the gas mixing module is in a vacuum state, and before the inert gas and the gas to be tested enter the reduction module, the reduction module is in a vacuum state, which not only further improves the isotope calibration rate, but also reduces the input of inert gas during the transmission, reduction, and calibration of the gas to be tested, further reducing the isotope calibration cost, and is suitable for isotope calibration in most laboratories. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0021] Figure 1 It is a schematic diagram of the system structure of the present invention. DETAILED DESCRIPTION

[0022] The following will be combined with the 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 without creative work are within the scope of protection of the present invention.

[0023] Embodiment 1:

[0024] Example 1 of the present invention discloses a stable isotope mass spectrometry system based on reduction reaction, such as Figure 1 As shown, it includes: an oxidation module, a reduction module, a first sample injection module, a second sample injection module, a gas mixing module, a first vacuum module, a second vacuum module, and a stable isotope mass spectrometer;

[0025] The first injection module continuously introduces inert gas into the oxidation module, and the inert gas enters the gas mixing module through the oxidation module; the second injection module introduces the gas to be tested into the gas mixing module and passes through the reduction module together with the inert gas, and then enters into the stable isotope mass spectrometer to obtain the isotope ratio of the gas to be tested; the first vacuum module is used to make the gas mixing module in a vacuum state before the inert gas and the gas to be tested enter the gas mixing module; the second vacuum module is used to make the reduction module in a vacuum state before the inert gas and the gas to be tested enter the reduction module.

[0026] The inert gas is argon, which is easier to obtain and has lower cost, and can effectively reduce the cost of isotope calibration.

[0027] A polytetrafluoroethylene plug is provided at the connection between the gas mixing module and the oxidation module, the second sample injection module and the reduction module.

[0028] The connection between the gas mixing module and the oxidation module, the second sample injection module and the reduction module is also provided with an internal thread for moving the polytetrafluoroethylene stopcock up and down to control the connection and closure of the connection.

[0029] The polytetrafluoroethylene plug is also provided with at least one sealing ring used in conjunction with the polytetrafluoroethylene plug.

[0030] The gases to be tested are nitrogen, nitrous oxide, nitric oxide, and carbon dioxide.

[0031] The second injection module is a gas-tight syringe.

[0032] The reduction module is filled with active copper particles (hot copper), which can reduce the test gases nitrous oxide and nitric oxide to nitrogen. After entering the stable isotope mass spectrometer, the required reference gases with known isotope ratios are only nitrogen and carbon dioxide, which can realize the calibration of the isotope ratios of multiple test gases including nitrogen, nitrous oxide, nitric oxide, and carbon dioxide working standard gases.

[0033] As for nitrogen and carbon dioxide, these two gases are the final products of the thermal copper reduction reaction. Their properties do not change after entering the reduction tube. Therefore, the gas inlet assembly is a channel that enables them to enter the stability isotope mass spectrometer.

[0034] The first vacuum module is used to put the gas mixing module into a vacuum state before the inert gas and the gas to be tested enter the gas mixing module, specifically:

[0035] Before the inert gas and the gas to be tested enter the gas mixing module, the polytetrafluoroethylene stopcock at the connection between the gas mixing module, the oxidation module and the second injection module is controlled to be in a closed state. After the inside of the gas mixing module is vacuum-treated by the first vacuum module, the polytetrafluoroethylene stopcock at the connection between the gas mixing module, the oxidation module and the second injection module is connected.

[0036] By using the first vacuum module, the gas mixing module is placed in a vacuum state before the inert gas and the gas to be tested enter the gas mixing module, which can not only further improve the calibration rate, but also reduce the input of inert gas during the transmission, reduction and calibration of the gas to be tested, thereby reducing the isotope calibration cost.

[0037] The second vacuum module is used to put the reduction module in a vacuum state before the inert gas and the gas to be tested enter the reduction module, specifically:

[0038] Before the inert gas and the gas to be tested enter the reduction module, the polytetrafluoroethylene stopcock at the connection between the gas mixing module and the reduction module is controlled to be in a closed state. After the inside of the reduction module is vacuum-treated by the second vacuum module, the polytetrafluoroethylene stopcock at the connection between the gas mixing module and the reduction module is connected.

[0039] By using the second vacuum module, the reduction module is placed in a vacuum state before the inert gas and the gas to be tested enter the reduction module, which can not only further increase the calibration rate, but also reduce the input of inert gas during the transmission, reduction and calibration of the gas to be tested, thereby reducing the isotope calibration cost.

[0040] The first vacuum module and the second vacuum module are both vacuum pumps.

[0041] The overall implementation process of the present invention is as follows:

[0042] The first injection module continuously introduces inert gas to the oxidation module, and the second injection module introduces the gas to be tested to the gas mixing module. At this time, the polytetrafluoroethylene stopcock at the connection between the gas mixing module, the oxidation module and the second injection module is in a closed state. After the inside of the gas mixing module is vacuum-treated by the first vacuum module, the polytetrafluoroethylene stopcock at the connection between the gas mixing module, the oxidation module and the second injection module is connected, and the inert gas and the gas to be tested enter the gas mixing module. At this time, the polytetrafluoroethylene stopcock at the connection between the gas mixing module and the reduction module is in a closed state. After the inside of the reduction module is vacuum-treated by the second vacuum module, the polytetrafluoroethylene stopcock at the connection between the gas mixing module and the reduction module is connected, and the gas to be tested and the gas to be tested enter and pass through the reduction module. The nitrous oxide and nitric oxide to be tested gases are reduced to nitrogen by hot copper, while the properties of the nitrogen and carbon dioxide to be tested gases remain unchanged, and enter the stable isotope mass spectrometer to achieve accurate calibration of the isotope ratio of the gas to be tested.

[0043] The embodiment of the present invention discloses a stable isotope mass spectrometry system based on reduction reaction. Different from the expensive price of the existing stable isotope mass spectrometry dual-path system, by using the hot copper of the reduction module to reduce the gas to be tested, the isotope accurate calibration of nitrogen, nitrous oxide, nitric oxide and carbon dioxide with low cost is achieved, and the inert gas argon, which is easier to obtain and has lower cost, is used as a continuous input flow, and cooperates with the first vacuum module and the second vacuum module, so that before the inert gas and the gas to be tested enter the gas mixing module, the gas mixing module is in a vacuum state, and before the inert gas and the gas to be tested enter the reduction module, the reduction module is in a vacuum state, which not only further improves the isotope calibration rate, but also reduces the input of inert gas in the process of transmission, reduction and calibration of the gas to be tested, further reduces the isotope calibration cost, and is suitable for isotope calibration in most laboratories.

[0044] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0045] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A stable isotope mass spectrometry system based on reduction reaction, characterized in that: It includes: an oxidation module, a reduction module, a first sample injection module, a second sample injection module, a gas mixing module, a first vacuum module, a second vacuum module, and a stable isotope mass spectrometer; The first injection module continuously introduces inert gas into the oxidation module, and the inert gas enters the gas mixing module through the oxidation module; the second injection module introduces the gas to be tested into the gas mixing module and passes through the reduction module together with the inert gas, and is introduced into the stable isotope mass spectrometer to obtain the isotope ratio of the gas to be tested; the first vacuum module is used to make the gas mixing module in a vacuum state before the inert gas and the gas to be tested enter the gas mixing module; the second vacuum module is used to make the reduction module in a vacuum state before the inert gas and the gas to be tested enter the reduction module.

2. A stable isotope mass spectrometry system based on reduction reaction according to claim 1, characterized in that: The inert gas is argon.

3. The stable isotope mass spectrometry system based on reduction reaction according to claim 1, characterized in that: A polytetrafluoroethylene stopcock is provided at the connection between the gas mixing module and the oxidation module, the second sample injection module and the reduction module.

4. The stable isotope mass spectrometry system based on reduction reaction according to claim 3, characterized in that: The connection between the gas mixing module and the oxidation module, the second injection module and the reduction module is also provided with an internal thread for moving the polytetrafluoroethylene stopcock up and down to control the connection and closure of the connection.

5. The stable isotope mass spectrometry system based on reduction reaction according to claim 3, characterized in that: The polytetrafluoroethylene plug is also provided with at least one sealing ring used in conjunction with the polytetrafluoroethylene plug.

6. The stable isotope mass spectrometry system based on reduction reaction according to claim 1, characterized in that: The gases to be tested are nitrogen, nitrous oxide, nitric oxide, and carbon dioxide.

7. The stable isotope mass spectrometry system based on reduction reaction according to claim 1, characterized in that: The reduction module is filled with active copper particles.

8. The stable isotope mass spectrometry system based on reduction reaction according to claim 4, characterized in that: The first vacuum module is used to put the gas mixing module in a vacuum state before the inert gas and the gas to be tested enter the gas mixing module, specifically: Before the inert gas and the gas to be tested enter the gas mixing module, the polytetrafluoroethylene stopcock at the connection between the gas mixing module, the oxidation module and the second injection module is controlled to be in a closed state. After the inside of the gas mixing module is vacuum-treated by the first vacuum module, the polytetrafluoroethylene stopcock at the connection between the gas mixing module, the oxidation module and the second injection module is connected.

9. The stable isotope mass spectrometry system based on reduction reaction according to claim 4, characterized in that: The second vacuum module is used to put the reduction module in a vacuum state before the inert gas and the gas to be tested enter the reduction module, specifically: Before the inert gas and the gas to be tested enter the reduction module, the polytetrafluoroethylene plug at the connection between the gas mixing module and the reduction module is controlled to be in a closed state. After the interior of the reduction module is vacuum-treated by the second vacuum module, the polytetrafluoroethylene plug at the connection between the gas mixing module and the reduction module is connected.

10. The stable isotope mass spectrometry system based on reduction reaction according to claim 1, characterized in that: The first vacuum module and the second vacuum module are both vacuum pumps.

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