Device and method for quantitatively detecting trace gas phase impurities in high-purity deuterium gas

Abstract

The invention relates to a device and a method for quantitatively detecting trace gas phase impurities in high-purity deuterium gas, the device comprises a sample pretreatment system and a sample determination system, one end of a gas chromatograph gas inlet pipeline is communicated with the sample pretreatment system, and the other end of the gas chromatograph gas inlet pipeline is communicated with the sample determination system; according to the method, helium is used as carrier gas, gas chromatography is matched with a plasma emission detector, and oxygen, nitrogen, carbon monoxide, carbon dioxide, methane, non-methane total hydrocarbon, hydrogen and deuteride can be completely separated and detected through one-time sample injection by means of precise matching of a low-temperature-resistant chromatographic column and a sample injection valve through a constant-pressure automatic sample injection and valve cutting technology. The method has the advantages of high automation, less man-made interference, good component separation effect, accurate detection and low component detection limit, the detection limit of oxygen, nitrogen, carbon monoxide, carbon dioxide, methane, non-methane hydrocarbon and hydrogen can reach 10 ppbv, and the detection limit of hydrogen deuteride can reach 1 ppmv.

Description

Technical Field

[0001] The invention belongs to the technical field of gas analysis, and in particular relates to a device and method for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas. Background Art

[0002] In nuclear science, isotope research, semiconductor material preparation and many high-tech fields, high-purity deuterium gas is a key isotope gas. Its purity and trace impurity components have a crucial impact on the accuracy of experimental results and product performance. Trace gas-phase impurities in high-purity deuterium gas, such as hydrogen, nitrogen, oxygen, carbon monoxide, carbon dioxide and water vapor, even in extremely low concentrations, may have an adverse effect on subsequent process steps, such as increasing defects in semiconductor materials and affecting the efficiency and stability of nuclear fusion reactions. Therefore, it is particularly important to conduct accurate and efficient quantitative analysis of trace gas-phase impurities in high-purity deuterium gas.

[0003] Traditional analysis methods, such as chemical titration, mass spectrometry or manual injection gas chromatography, have problems such as complex operation, large human error, large sample consumption, long analysis cycle and insufficient sensitivity for detecting some low-concentration impurities. Patent CN116559348A discloses a gas chromatography column system for detecting high-purity deuterium gas, including a main pipe connected to the column box inlet, a ShinCronST filling column connected to the main pipe through a branch pipe 1, and a modified Al2O3 chromatographic column connected to the main pipe through a branch pipe 2; wherein an inlet valve 1 is arranged on the branch pipe 1, and the gas to be tested after passing through the ShinCronST filling column enters the gas chromatography detector with an outlet valve 1 for detection; wherein an inlet valve 2 is arranged on the branch pipe 2, and the gas to be tested after passing through the modified Al2O3 chromatographic column enters the gas chromatography detector with an outlet valve 2 for detection. However, the impurity detection in deuterium gas in this method is not comprehensive. In addition, this method is a manual injection, which not only makes it difficult to ensure the accuracy and consistency of each injection, but is also easily affected by the operator's proficiency and external environmental factors, thereby limiting the accuracy and repeatability of the analysis results. Summary of the invention

[0004] In order to overcome the above-mentioned problems existing in the prior art, the purpose of the present invention is to provide a device and method for quantitative detection of trace gas-phase impurities in high-purity deuterium gas, which can achieve the technical effect of simultaneously detecting oxygen, nitrogen, carbon monoxide, carbon dioxide, methane, non-methane total hydrocarbons, non-methane, non-methane total hydrocarbons, hydrogen and deuterated hydrogen through constant pressure automatic sampling and valve cutting technology, through a low-temperature resistant chromatographic column, etc.

[0005] To achieve the purpose of the present invention, the specific technical solutions provided by the present invention are as follows:

[0006] A device for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas, comprising a sample pretreatment system and a sample measurement system;

[0007] One end of the gas chromatograph air inlet pipeline is connected to the sample pretreatment system, and the other end is connected to the sample measurement system;

[0008] The sample pretreatment system includes an inert gas source, a standard gas source, a sample source and a vacuum unit connected to the gas chromatograph inlet pipeline;

[0009] The sample determination system comprises a first detection unit, a second detection unit, a third detection unit and a fourth detection unit which are arranged in parallel and connected in sequence inside the gas chromatograph;

[0010] The first detection unit includes a first quantitative ring, the second detection unit includes a second quantitative ring, the third detection unit includes a third quantitative ring, and the fourth detection unit includes a fourth quantitative ring; the first to fourth quantitative rings are connected in sequence through valves and pipelines to form a sample gas path; the first to fourth quantitative rings are used to store the gas to be detected;

[0011] The first detection unit is provided with a first gas circuit, and the first quantitative loop is connected to the first gas circuit; the second detection unit is provided with a second gas circuit, and the second quantitative loop is connected to the second gas circuit; the third detection unit is provided with a third gas circuit, and the third quantitative loop is connected to the third gas circuit; the fourth detection unit is provided with a fourth gas circuit, and the fourth quantitative loop is connected to the fourth gas circuit; the first gas circuit is provided with a first chromatographic column and a second chromatographic column for separating gases, the second gas circuit is provided with a sixth chromatographic column and a seventh chromatographic column for separating gases, the third gas circuit is provided with a third chromatographic column for separating gases, and the fourth gas circuit is provided with a fourth chromatographic column and a fifth chromatographic column for separating gases; the first gas circuit is also provided with a first detector for detecting gas components, the third gas circuit is also provided with a second detector for detecting gas components, the fourth gas circuit is also provided with a third detector for detecting gas components, and the second gas circuit is connected with the detectors on the third gas circuit and the fourth gas circuit through a connecting pipeline;

[0012] The first detection unit is used to detect O2 and N2 impurities in high-purity deuterium gas, the second detection unit is used to detect NMHC and CO2 impurities in high-purity deuterium gas, the third detection unit is used to detect H2 and HD impurities in high-purity deuterium gas, and the fourth detection unit is used to detect CH4 and CO impurities in high-purity deuterium gas.

[0013] Preferably, in the sample pretreatment system, the inert gas source connected to the gas chromatograph pipeline includes two groups of pipelines, the first inert gas source and the gas chromatograph are connected along the gas direction of the pipeline, and the first filter, the first pressure reducer and the second pressure reducer are sequentially arranged along the gas direction of the pipeline, and the second inert gas source and the gas chromatograph are connected along the gas direction of the pipeline, and the third pressure reducer, the eighth pneumatic diaphragm valve, the ninth pneumatic diaphragm valve and the mass flow controller are sequentially arranged;

[0014] One end of the ninth pneumatic diaphragm valve is connected to the mass flow controller, and the other end is respectively connected to the standard gas source, the first sample gas source, the second sample gas source and the vacuum unit;

[0015] A fourth pressure reducer and a seventh pneumatic diaphragm valve are sequentially arranged along the gas direction of the pipeline connecting the standard gas source and the ninth pneumatic diaphragm valve;

[0016] A second filter, a first pneumatic diaphragm valve, a fifth pressure reducer and a fifth pneumatic diaphragm valve are sequentially arranged along the gas direction on the pipeline connecting the first sample gas source and the ninth pneumatic diaphragm valve;

[0017] A third filter, a second pneumatic diaphragm valve, a sixth pressure reducer and a sixth pneumatic diaphragm valve are sequentially arranged along the gas direction on the pipeline connecting the second sample gas source and the ninth pneumatic diaphragm valve;

[0018] A tenth pneumatic diaphragm valve is arranged on the pipeline connecting the vacuum pumping unit and the ninth pneumatic diaphragm valve.

[0019] Preferably, on the pipeline connecting the first inert gas source and the gas chromatograph, a first pressure sensor is installed between the first filter and the first pressure reducer, and a second pressure sensor is installed between the second pressure reducer and the gas chromatograph;

[0020] A third pressure sensor is installed on the pipeline connecting the second inert gas source and the gas chromatograph, between the second inert gas source and the eighth pneumatic diaphragm valve;

[0021] A fourth pressure sensor is installed on the pipeline connecting the standard gas source and the ninth pneumatic diaphragm valve, between the standard gas source and the seventh pneumatic diaphragm valve;

[0022] The gas chromatograph is also connected to a fifth pressure sensor in the sample pretreatment system.

[0023] Preferably, on the pipeline connecting the first sample gas source and the ninth pneumatic diaphragm valve, a third pneumatic diaphragm valve is connected in parallel at both ends of the fifth pressure reducer; on the pipeline connecting the second sample gas source and the ninth pneumatic diaphragm valve, a fourth pneumatic diaphragm valve is connected in parallel at both ends of the sixth pressure reducer.

[0024] Preferably, the sample measurement system further comprises eight groups of six-way valves and one group of ten-way valves for transmitting gas, which are respectively arranged in the first detection unit, the second detection unit, the third detection unit and the fourth detection unit;

[0025] A first six-way valve, a second six-way valve and a third six-way valve for transmitting gas are provided on the first gas path of the first detection unit;

[0026] A ten-way valve for transmitting gas is provided on the fourth gas path of the second detection unit;

[0027] A fourth six-way valve and a fifth six-way valve for transmitting gas are provided on the second gas path of the third detection unit;

[0028] A sixth six-way valve, a seventh six-way valve and an eighth six-way valve for transmitting gas are provided on the third gas path of the fourth detection unit;

[0029] The six-way valve and the ten-way valve are both divided into two states, including a first state and a second state;

[0030] The eight groups of six-way valves are all provided with six interfaces distributed counterclockwise. In the first state, interface No. 1 is connected to interface No. 2, interface No. 3 is connected to interface No. 4, and interface No. 5 is connected to interface No. 6; in the second state, interface No. 1 is connected to interface No. 6, interface No. 2 is connected to interface No. 3, and interface No. 4 is connected to interface No. 5.

[0031] The ten-way valve is provided with ten interfaces distributed counterclockwise. In the first state, interface No. 1 is connected to interface No. 2, interface No. 3 is connected to interface No. 4, interface No. 5 is connected to interface No. 6, interface No. 7 is connected to interface No. 8, and interface No. 9 is connected to interface No. 10. In the second state, interface No. 1 is connected to interface No. 10, interface No. 2 is connected to interface No. 3, interface No. 4 is connected to interface No. 5, interface No. 6 is connected to interface No. 7, and interface No. 8 is connected to interface No. 9.

[0032] One end of the first quantitative ring on the first detection unit is connected to the No. 3 interface of the first six-way valve, and the other end is connected to the No. 6 interface of the first six-way valve;

[0033] One end of the second quantitative ring on the second detection unit is connected to the No. 2 interface of the ten-way valve, and the other end is connected to the No. 9 interface of the ten-way valve;

[0034] One end of the third quantitative ring on the third detection unit is connected to the No. 3 interface of the fourth six-way valve, and the other end is connected to the No. 6 interface of the fourth six-way valve;

[0035] One end of the fourth quantitative ring on the fourth detection unit is communicated with the No. 3 interface of the sixth six-way valve, and the other end is communicated with the No. 6 interface of the sixth six-way valve.

[0036] Preferably, in the sample measurement system, the sample injection gas circuit includes a first six-way valve, a ten-way valve, a fourth six-way valve and a sixth six-way valve which are connected in sequence; the sample inlet is connected to interface No. 4 of the first six-way valve, interface No. 6 of the first six-way valve is connected to interface No. 10 of the ten-way valve, interface No. 1 of the ten-way valve is connected to interface No. 5 of the fourth six-way valve, interface No. 4 of the fourth six-way valve is connected to interface No. 4 of the sixth six-way valve, and interface No. 5 of the sixth six-way valve is connected to the sample outlet.

[0037] Preferably, the first gas path on the first detection unit also includes a first carrier gas connected to the No. 2 interface of the first six-way valve, a second carrier gas connected to the No. 6 interface of the second six-way valve; a first vent air resistor connected to the No. 4 interface of the second six-way valve, a second vent air resistor connected to the No. 4 interface of the third six-way valve; the No. 3 interface of the second six-way valve is connected to the No. 5 interface; one end of the first chromatographic column is connected to the No. 1 interface of the first six-way valve, and the other end is connected to the No. 2 interface of the second six-way valve; one end of the second chromatographic column is connected to the No. 1 interface of the second six-way valve , the other end is connected to the No. 2 interface of the third six-way valve, and the first detector is connected to the No. 1 interface of the third six-way valve; the second gas circuit on the second detection unit also includes a seventh carrier gas connected to the No. 3 interface of the ten-way valve, and an eighth carrier gas connected to the No. 6 interface of the ten-way valve; one end of the sixth chromatographic column is connected to the No. 4 interface of the ten-way valve, and the other end is connected to the No. 8 interface of the ten-way valve; one end of the seventh chromatographic column is connected to the No. 5 interface of the ten-way valve, and the other end is connected to the No. 6 interface of the eighth six-way valve; the No. 7 interface of the ten-way valve is connected to the No. 6 interface of the third six-way valve.

[0038] Preferably, the third gas circuit on the third detection unit also includes a third carrier gas connected to the No. 2 interface of the fourth six-way valve, a fourth carrier gas connected to the No. 6 interface of the fifth six-way valve; a third venting air resistor connected to the No. 4 interface of the fifth six-way valve; the No. 3 interface of the fifth six-way valve is connected to the No. 5 interface; one end of the third chromatographic column is connected to the No. 1 interface of the fourth six-way valve, and the other end is connected to the No. 2 interface of the fifth six-way valve; the second detector is connected to the No. 1 interface of the fifth six-way valve, and a liquid nitrogen tank is installed on the connecting pipeline.

[0039] Preferably, the fourth gas circuit on the fourth detection unit also includes a fifth carrier gas connected to the No. 2 interface of the sixth six-way valve, and a sixth carrier gas connected to the No. 6 interface of the seventh six-way valve; a fourth vent air resistor connected to the No. 4 interface of the seventh six-way valve, and a fifth vent air resistor connected to the No. 4 interface of the eighth six-way valve; the No. 3 interface of the seventh six-way valve is connected to the No. 5 interface; one end of the fourth chromatographic column is connected to the No. 1 interface of the sixth six-way valve, and the other end is connected to the No. 2 interface of the seventh six-way valve; one end of the fifth chromatographic column is connected to the No. 1 interface of the seventh six-way valve, and the other end is connected to the No. 2 interface of the seventh six-way valve; one end of the fifth chromatographic column is connected to the No. 1 interface of the seventh six-way valve, and the other end is connected to the No. 2 interface of the eighth six-way valve, and the third detector is connected to the No. 1 interface of the eighth six-way valve.

[0040] The present invention also provides a method for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas, which is implemented by a device for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas, completing a sample pretreatment process through a sample pretreatment system, and completing a sample determination process through a sample determination system;

[0041] The sample pretreatment process includes the following steps:

[0042] S1, pipeline replacement: open the vacuum unit, the tenth pneumatic diaphragm valve, the ninth pneumatic diaphragm valve, the seventh pneumatic diaphragm valve, the fifth pneumatic diaphragm valve, the third pneumatic diaphragm valve, the first pneumatic diaphragm valve, and the mass flow controller opening is set to 100% in sequence. When the pressure of the fifth pressure sensor is ≤-0.095MPa, keep it for 10s, and then close the vacuum unit and the tenth pneumatic diaphragm valve;

[0043] Open the second inert gas source and the eighth pneumatic diaphragm valve. When the pressure of the fifth pressure sensor is ≥0.2Mpa, keep it for 10s, and then close the second inert gas source and the eighth pneumatic diaphragm valve.

[0044] Open the vacuum unit and the tenth pneumatic diaphragm valve. When the pressure of the fifth pressure sensor is ≤-0.095Mpa, close the vacuum unit and the tenth pneumatic diaphragm valve.

[0045] Repeat the pipeline replacement three times, and close the ninth pneumatic diaphragm valve, the seventh pneumatic diaphragm valve, the fifth pneumatic diaphragm valve, the third pneumatic diaphragm valve, and the first pneumatic diaphragm valve in sequence;

[0046] S2, standard gas replacement pipeline: open the main valve of the standard gas source, and then open the seventh pneumatic diaphragm valve and the ninth pneumatic diaphragm valve in sequence. When the pressure of the fifth pressure sensor is ≥0.1Mpa, keep it for 10s and close the seventh pneumatic diaphragm valve;

[0047] Open the vacuum unit and the tenth pneumatic diaphragm valve, and when the pressure of the fifth pressure sensor is ≤-0.095Mpa, close the vacuum unit and the tenth pneumatic diaphragm valve;

[0048] Repeat the standard gas replacement pipeline 3 times;

[0049] S3, standard gas sampling: open the mass flow controller and set the opening to 10%, open the seventh pneumatic diaphragm valve, when the pressure of the fifth pressure sensor = 0.02Mpa, close the seventh pneumatic diaphragm valve, and start the gas chromatograph to collect data. After 107s, open the vacuum unit and the tenth pneumatic diaphragm valve, open the mass flow controller and set the opening to 100%, when the pressure of the fifth pressure sensor is ≤-0.095Mpa, close the vacuum unit, the tenth pneumatic diaphragm valve and the ninth pneumatic diaphragm valve; the gas chromatograph collects data, and the analysis takes 1800s to complete the detection;

[0050] S4, sample gas replacement pipeline: open the first sample gas source main valve, open the first pneumatic diaphragm valve, the fifth pneumatic diaphragm valve and the ninth pneumatic diaphragm valve. When the pressure of the fifth pressure sensor is ≥0.1Mpa, keep it for 10s and close the first pneumatic diaphragm valve;

[0051] Open the vacuum unit and the tenth pneumatic diaphragm valve, and when the pressure of the fifth pressure sensor is ≤-0.095Mpa, close the vacuum unit and the tenth pneumatic diaphragm valve;

[0052] Repeat the sample gas replacement pipeline 3 times;

[0053] S5, sample gas injection: open the mass flow controller and set the opening to 10%, open the first pneumatic diaphragm valve, when the pressure of the fifth pressure sensor = 0.02Mpa, close the first pneumatic diaphragm valve, start the gas chromatograph to collect data, open the vacuum unit and the tenth pneumatic diaphragm valve after 107s, open the mass flow controller and set the opening to 100%, when the pressure of the fifth pressure sensor ≤-0.095Mpa, close the vacuum unit, the tenth pneumatic diaphragm valve and the ninth pneumatic diaphragm valve; the gas chromatograph collects data, and the analysis takes 1800s to complete the detection;

[0054] In steps S3 and S5, when the gas chromatograph is started to collect data, the sample measurement process is completed by the sample measurement system in the gas chromatograph.

[0055] The device and method for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas of the present invention have the following beneficial effects:

[0056] 1. This method uses helium as carrier gas, and the gas chromatograph is equipped with a plasma emission detector. Through constant pressure automatic injection and valve cutting technology, the low-temperature resistant chromatographic column and the injection valve are precisely matched to achieve one injection to completely separate oxygen, nitrogen, carbon monoxide, carbon dioxide, methane, non-methane total hydrocarbons, hydrogen and deuterated hydrogen for detection. The detection limit of oxygen, nitrogen, carbon monoxide, carbon dioxide, methane, non-methane total hydrocarbons and hydrogen can reach 10ppb, and the detection limit of deuterated hydrogen can reach 1ppm.

[0057] 2. This method has high automation, less human interference, small sample dosage, good separation effect of each component, accurate detection, and low detection limit of each component. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 This is a gas flow chart of the sample pretreatment system of the present invention;

[0059] Figure 2 This is a gas path state flow chart of the sample measurement system when collecting data at 0s and 1800s in Example 2 of the present invention;

[0060] Figure 3 This is a gas path state flow chart of the sample measurement system at the 60th second of data collection in Example 2 of the present invention;

[0061] Figure 4This is a gas path state flow chart of the sample measurement system when collecting data at 100s, 140s, 175s, 230s and 500s in Example 2 of the present invention;

[0062] Figure 5 This is a gas path state flow chart of the sample measurement system when collecting data at 120s and 265s in Example 2 of the present invention;

[0063] Figure 6 This is a gas path state flow chart of the sample measurement system when collecting data at 150s and 200s in Example 2 of the present invention;

[0064] Figure 7 This is a gas path state flow chart of the sample measurement system at the 290th second of data collection in Example 2 of the present invention;

[0065] Figure 8 This is a gas path state flow chart of the sample measurement system at the 310th second of data collection in Example 2 of the present invention;

[0066] Fig. 9 This is a gas path state flow chart of the sample measurement system when collecting data at 600s and 980s in Example 2 of the present invention;

[0067] Fig.10 This is a gas path state flow chart of the sample measurement system at the 615th second of data collection in Example 2 of the present invention;

[0068] Fig.11 The chromatograms of oxygen, nitrogen and hydrogen detection in Example 2 of the present invention are shown;

[0069] Fig.12 This is a chromatogram of deuterated hydrogen detection in Example 2 of the present invention;

[0070] Fig.13 The chromatogram of methane, carbon monoxide and carbon dioxide detection in Example 2 of the present invention;

[0071] Fig.14 This is a chromatogram of non-methane total hydrocarbon detection in Example 2 of the present invention;

[0072] Explanation of the markings in the figure: 1. First inert gas source; 11. First filter; 12. First pressure reducer; 13. Second pressure reducer; 14. First pressure sensor; 15. Second pressure sensor; 2. Second inert gas source; 21. Third pressure reducer; 22. Eighth pneumatic diaphragm valve; 23. Third pressure sensor; 3. Standard gas source; 31. Fourth pressure reducer; 32. Seventh pneumatic diaphragm valve; 33. Fourth pressure sensor; 4. First sample gas source; 41. Second filter ; 42, first pneumatic diaphragm valve; 43, fifth pressure reducer; 44, fifth pneumatic diaphragm valve; 45, third pneumatic diaphragm valve; 5, second sample gas source; 51, third filter; 52, second pneumatic diaphragm valve; 53, sixth pressure reducer; 54, sixth pneumatic diaphragm valve; 55, fourth pneumatic diaphragm valve; 6, vacuum unit; 61, tenth pneumatic diaphragm valve; 7, ninth pneumatic diaphragm valve; 8, mass flow controller; 9, fifth pressure sensor; 10, gas chromatograph;

[0073] 101, sample inlet; 102, sample outlet; 201, first six-way valve; 202, second six-way valve; 203, third six-way valve; 204, fourth six-way valve; 205, fifth six-way valve; 206, sixth six-way valve; 207, seventh six-way valve; 208, eighth six-way valve; 209, ten-way valve; 301, first carrier gas; 302, second carrier gas; 303, third carrier gas; 304, fourth carrier gas; 305, fifth carrier gas; 306, sixth carrier gas; 307, seventh carrier gas; 308, eighth carrier gas; 401, first chromatographic column; 40 2. Second chromatographic column; 403. Third chromatographic column; 404. Fourth chromatographic column; 405. Fifth chromatographic column; 406. Sixth chromatographic column; 407. Seventh chromatographic column; 501. First vent air resistance; 502. Second vent air resistance; 503. Third vent air resistance; 504. Fourth vent air resistance; 505. Fifth vent air resistance; 601. First quantitative ring; 602. Second quantitative ring; 603. Third quantitative ring; 604. Fourth quantitative ring; 701. Liquid nitrogen tank; 801. First detector; 802. Second detector; 803. Third detector. DETAILED DESCRIPTION

[0074] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation method, structure, characteristics and effects of the present invention are described in detail below in combination with the preferred embodiments.

[0075] Device Example 1

[0076] This embodiment discloses a device for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas, including a sample pretreatment system and a sample determination system; wherein one end of the air inlet pipeline of the gas chromatograph 10 is connected to the sample pretreatment system, and the other end is connected to the sample determination system.

[0077] like Figure 1 , which is a gas flow chart of the sample pretreatment system of the present invention. The sample pretreatment system of this embodiment includes an inert gas source connected to the gas inlet pipeline of the gas chromatograph 10, a standard gas source 3, a sample source and a vacuum unit 6.

[0078] The inert gas source connected to the air inlet pipeline of the gas chromatograph 10 includes two groups of pipelines. A first filter 11, a first pressure reducer 12 and a second pressure reducer 13 are sequentially arranged along the direction of the gas on the pipeline connecting the first inert gas source 1 and the gas chromatograph 10; wherein a first pressure sensor 14 is installed between the first filter 11 and the first pressure reducer 12, and a second pressure sensor 15 is installed between the second pressure reducer 13 and the gas chromatograph 10.

[0079] A third pressure reducer 21, an eighth pneumatic diaphragm valve 22, a ninth pneumatic diaphragm valve 7 and a mass flow controller 8 are sequentially arranged along the gas direction of the pipeline connecting the second inert gas source 2 and the gas chromatograph 10; wherein a third pressure sensor 23 is installed between the second inert gas source 2 and the eighth pneumatic diaphragm valve 22.

[0080] More specifically, the ninth pneumatic diaphragm valve 7 is connected to multiple groups of pipelines. One end of the ninth pneumatic diaphragm valve 7 is connected to the mass flow controller 8, and the other end thereof is respectively connected to the second inert gas source 2, the standard gas source 3, the first sample gas source 4, the second sample gas source 5 and the vacuum unit 6.

[0081] A fourth pressure reducer 31 and a seventh pneumatic diaphragm valve 32 are sequentially arranged along the gas direction of the pipeline connecting the calibration gas source 3 and the ninth pneumatic diaphragm valve 7 ; wherein a fourth pressure sensor 33 is installed between the calibration gas source 3 and the seventh pneumatic diaphragm valve 32 .

[0082] A second filter 41, a first pneumatic diaphragm valve 42, a fifth pressure reducer 43 and a fifth pneumatic diaphragm valve 44 are sequentially arranged along the gas direction of the pipeline connecting the first sample gas source 4 and the ninth pneumatic diaphragm valve 7; a third pneumatic diaphragm valve 45 is connected in parallel at both ends of the fifth pressure reducer 43.

[0083] A third filter 51, a second pneumatic diaphragm valve 52, a sixth pressure reducer 53 and a sixth pneumatic diaphragm valve 54 are sequentially arranged along the gas direction of the pipeline connecting the second sample gas source 5 and the ninth pneumatic diaphragm valve 7; a fourth pneumatic diaphragm valve 55 is connected in parallel at both ends of the sixth pressure reducer 53.

[0084] A tenth pneumatic diaphragm valve 61 is further provided on the pipeline connecting the vacuum unit 6 and the ninth pneumatic diaphragm valve 7 .

[0085] On the basis of the above, the gas chromatograph 10 in the sample pretreatment system is further connected to a fifth pressure sensor 9 .

[0086] like Figure 2-10 , which is a gas path state flow chart of the sample measurement system of the present invention; the sample measurement system of this embodiment includes a first detection unit, a second detection unit, a third detection unit and a fourth detection unit which are arranged in parallel and connected in sequence inside the gas chromatograph 10;

[0087] Specifically, the sample measurement system further includes four sets of quantitative rings, eight sets of six-way valves and one set of ten-way valves 209 for transmitting gas, which are respectively arranged in the first detection unit, the second detection unit, the third detection unit and the fourth detection unit.

[0088] The six-way valve and the ten-way valve 209 are both divided into two states, including a first state and a second state; Figure 2-10 As shown, in the first state, the pipeline connection state in the valve is shown by the solid line, and in the second state, the pipeline connection state in the valve is shown by the dotted line;

[0089] The eight groups of six-way valves are all provided with six interfaces distributed counterclockwise. In the first state, interface No. 1 is connected to interface No. 2, interface No. 3 is connected to interface No. 4, and interface No. 5 is connected to interface No. 6; in the second state, interface No. 1 is connected to interface No. 6, interface No. 2 is connected to interface No. 3, and interface No. 4 is connected to interface No. 5.

[0090] The ten-way valve 209 is provided with ten interfaces distributed counterclockwise. In the first state, interface No. 1 is connected to interface No. 2, interface No. 3 is connected to interface No. 4, interface No. 5 is connected to interface No. 6, interface No. 7 is connected to interface No. 8, and interface No. 9 is connected to interface No. 10. The second state is connected to interface No. 10, interface No. 2 is connected to interface No. 3, interface No. 4 is connected to interface No. 5, interface No. 6 is connected to interface No. 7, and interface No. 8 is connected to interface No. 9.

[0091] The first detection unit is provided with a first gas circuit, and the first gas circuit is provided with a first quantitative ring 601 for storing or transmitting gas, a first six-way valve 201, a second six-way valve 202 and a third six-way valve 203; one end of the first quantitative ring 601 is connected to the No. 3 interface of the first six-way valve 201, and the other end is connected to the No. 6 interface of the first six-way valve 201.

[0092] A second gas circuit is provided on the second detection unit, and a second quantitative ring 602 and a ten-way valve 209 for storing or transmitting gas are provided on the second gas circuit; one end of the second quantitative ring 602 is connected to the second interface of the ten-way valve 209, and the other end is connected to the ninth interface of the ten-way valve 209.

[0093] The third detection unit is provided with a third gas circuit, and the third gas circuit is provided with a third quantitative ring 603, a fourth six-way valve 204 and a fifth six-way valve 205 for storing or transmitting gas; one end of the third quantitative ring 603 is connected to the third interface of the fourth six-way valve 204, and the other end is connected to the sixth interface of the fourth six-way valve 204.

[0094] A fourth gas circuit is provided on the fourth detection unit, and a fourth quantitative ring 604, a sixth six-way valve 206, a seventh six-way valve 207 and an eighth six-way valve 208 for storing or transmitting gas are provided on the fourth gas circuit; one end of the fourth quantitative ring 604 is connected to the No. 3 interface of the sixth six-way valve 206, and the other end is connected to the No. 6 interface of the sixth six-way valve 206.

[0095] The sample measurement system also includes an injection unit, which is provided with an injection gas circuit, which includes a first six-way valve 201, a ten-way valve 209, a fourth six-way valve 204 and a sixth six-way valve 206 which are connected in sequence; the sample inlet 101 is connected to the fourth interface of the first six-way valve 201, the sixth interface of the first six-way valve 201 is connected to the tenth interface of the ten-way valve 209, the first interface of the ten-way valve 209 is connected to the fifth interface of the fourth six-way valve 204, the fourth interface of the fourth six-way valve 204 is connected to the fourth interface of the sixth six-way valve 206, and the fifth interface of the sixth six-way valve 206 is connected to the sample outlet 102.

[0096] The first gas path on the first detection unit is provided with a first chromatographic column 401 and a second chromatographic column 402 for separating gases, a first detector 801 for detecting gas components, and also includes a first carrier gas 301 connected to the No. 2 interface of the first six-way valve 201, a second carrier gas 302 connected to the No. 6 interface of the second six-way valve 202; a first vent air resistor 501 connected to the No. 4 interface of the second six-way valve 202, and a second vent air resistor 502 connected to the No. 4 interface of the third six-way valve 203. ; Interface No. 3 of the second six-way valve 202 is connected to interface No. 5; one end of the first chromatographic column 401 is connected to interface No. 1 of the first six-way valve 201, and the other end is connected to interface No. 2 of the second six-way valve 202; one end of the second chromatographic column 402 is connected to interface No. 1 of the second six-way valve 202, and the other end is connected to interface No. 2 of the third six-way valve 203, and the first detector 801 is connected to interface No. 1 of the third six-way valve 203; the first detection unit is used to detect the impurity content of O2 and N2 in high-purity deuterium gas.

[0097] The second gas path on the second detection unit is provided with a sixth chromatographic column 406 and a seventh chromatographic column 407 for separating gases, and also includes a seventh carrier gas 307 connected to the No. 3 interface of the ten-way valve 209, and an eighth carrier gas 308 connected to the No. 6 interface of the ten-way valve 209; one end of the sixth chromatographic column 406 is connected to the No. 4 interface of the ten-way valve 209, and the other end is connected to the No. 8 interface of the ten-way valve 209; one end of the seventh chromatographic column 407 is connected to the No. 5 interface of the ten-way valve 209, and the other end is connected to the No. 6 interface of the eighth six-way valve 208; the No. 7 interface of the ten-way valve 209 is connected to the No. 6 interface of the third six-way valve 203.

[0098] The third gas path on the third detection unit is provided with a third chromatographic column 403 for separating gases, a second detector 802 for detecting gas components, and also includes a third carrier gas 303 connected to the No. 2 interface of the fourth six-way valve 204, a fourth carrier gas 304 connected to the No. 6 interface of the fifth six-way valve 205; a third venting air resistor 503 connected to the No. 4 interface of the fifth six-way valve 205; the No. 3 interface of the fifth six-way valve 205 is connected to the No. 5 interface; one end of the third chromatographic column 403 is connected to the No. 1 interface of the fourth six-way valve 204, and the other end is connected to the No. 2 interface of the fifth six-way valve 205; the second detector 802 is connected to the No. 1 interface of the fifth six-way valve 205, and a liquid nitrogen tank 701 is installed on the connecting pipeline; the third detection unit is used to detect the H2 and HD impurity contents in the high-purity deuterium gas.

[0099] The fourth gas path on the fourth detection unit is provided with a fourth chromatographic column 404 and a fifth chromatographic column 405 for separating gases, and is provided with a third detector 802 for detecting gas components, and also includes a fifth carrier gas 305 connected to the second interface of the sixth six-way valve 206, a sixth carrier gas 306 connected to the sixth interface of the seventh six-way valve 207; a fourth vent air resistor 504 connected to the fourth interface of the seventh six-way valve 207, and a fifth vent air resistor 505 connected to the fourth interface of the eighth six-way valve 208; Interface No. 3 of the seventh six-way valve 207 is connected to interface No. 5; one end of the fourth chromatographic column 404 is connected to interface No. 1 of the sixth six-way valve 206, and the other end is connected to interface No. 2 of the seventh six-way valve 207; one end of the fifth chromatographic column 405 is connected to interface No. 1 of the seventh six-way valve 207, and the other end is connected to interface No. 2 of the eighth six-way valve 208, and the third detector 802 is connected to interface No. 1 of the eighth six-way valve 208; the fourth detection unit is used to detect the CH4 and CO impurity contents in the high-purity deuterium gas.

[0100] The second gas circuit on the second detection unit is connected to the detectors on the third gas circuit and the fourth gas circuit through a connecting pipeline, and is used to detect the NMHC and CO2 impurity content in the high-purity deuterium gas.

[0101] Method Example 2

[0102] This embodiment discloses a method for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas, which is implemented using a device for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas in device embodiment 1, completing a sample pretreatment process through a sample pretreatment system, and completing a sample determination process through a sample determination system.

[0103] The sample pretreatment process specifically includes the following steps:

[0104] S1, pipeline replacement: open the vacuum unit 6, the tenth pneumatic diaphragm valve 61, the ninth pneumatic diaphragm valve 7, the seventh pneumatic diaphragm valve 32, the fifth pneumatic diaphragm valve 44, the third pneumatic diaphragm valve 45, the first pneumatic diaphragm valve 42, and the mass flow controller 8 in sequence, and set the opening to 100%. When the pressure of the fifth pressure sensor 9 is ≤-0.095MPa, keep it for 10s, and then close the vacuum unit 6 and the tenth pneumatic diaphragm valve 61;

[0105] Open the second inert gas source 2 and the eighth pneumatic diaphragm valve 22. When the pressure of the fifth pressure sensor 9 is ≥ 0.2 MPa, keep it for 10 seconds, and then close the second inert gas source 2 and the eighth pneumatic diaphragm valve 22.

[0106] Open the vacuum unit 6 and the tenth pneumatic diaphragm valve 61, and when the pressure of the fifth pressure sensor is ≤-0.095Mpa, close the vacuum unit 6 and the tenth pneumatic diaphragm valve 61;

[0107] Repeat the pipeline replacement three times, and close the ninth pneumatic diaphragm valve 7, the seventh pneumatic diaphragm valve 32, the fifth pneumatic diaphragm valve 44, the third pneumatic diaphragm valve 45, and the first pneumatic diaphragm valve 42 in sequence;

[0108] S2, standard gas replacement pipeline: open the main valve of the standard gas source 3, and then open the seventh pneumatic diaphragm valve 32 and the ninth pneumatic diaphragm valve 7 in sequence. When the pressure of the fifth pressure sensor 9 is ≥0.1Mpa, keep it for 10s and close the seventh pneumatic diaphragm valve 32;

[0109] Open the vacuum unit 6 and the tenth pneumatic diaphragm valve 61, and when the pressure of the fifth pressure sensor 9 is ≤-0.095Mpa, close the vacuum unit 6 and the tenth pneumatic diaphragm valve 61;

[0110] Repeat the standard gas replacement pipeline 3 times;

[0111] S3, standard gas sampling: open the mass flow controller 8 and set the opening to 10%, open the seventh pneumatic diaphragm valve 32, when the pressure of the fifth pressure sensor 9 = 0.02Mpa, close the seventh pneumatic diaphragm valve 32, and start the gas chromatograph 10 to start collecting data. After 107s, open the vacuum unit 6 and the tenth pneumatic diaphragm valve 61, open the mass flow controller 8 and set the opening to 100%, when the pressure of the fifth pressure sensor 9 is ≤-0.095Mpa, close the vacuum unit 6, the tenth pneumatic diaphragm valve 61 and the ninth pneumatic diaphragm valve 7; the gas chromatograph 10 collects data, and the analysis takes 1800s to complete the detection;

[0112] S4, sample gas replacement pipeline: open the main valve of the first sample gas source 4, open the first pneumatic diaphragm valve 42, the fifth pneumatic diaphragm valve 44 and the ninth pneumatic diaphragm valve 7, when the pressure of the fifth pressure sensor 9 is ≥0.1Mpa, keep it for 10s, and close the first pneumatic diaphragm valve 42;

[0113] Open the vacuum unit 6 and the tenth pneumatic diaphragm valve 61, and when the pressure of the fifth pressure sensor 9 is ≤-0.095Mpa, close the vacuum unit 6 and the tenth pneumatic diaphragm valve 61;

[0114] Repeat the sample gas replacement pipeline 3 times;

[0115] S5, sample gas injection: open the mass flow controller 8 and set the opening to 10%, open the first pneumatic diaphragm valve 42, when the pressure of the fifth pressure sensor 9 = 0.02Mpa, close the first pneumatic diaphragm valve 42, and start the gas chromatograph 10 to start data collection. After 107s, open the vacuum unit 6 and the tenth pneumatic diaphragm valve 61, open the mass flow controller 8 and set the opening to 100%, when the pressure of the fifth pressure sensor 9 is ≤-0.095Mpa, close the vacuum unit 6, the tenth pneumatic diaphragm valve 61 and the ninth pneumatic diaphragm valve 7; the gas chromatograph 10 collects data, and the analysis takes 1800s to complete the detection;

[0116] In steps S3 and S5 , when the gas chromatograph 10 is started to collect data, the sample measurement process is completed by the sample measurement system in the gas chromatograph 10 . Figure 11-14 The chromatogram was detected for this example.

[0117] The gas chromatograph 10 is MultiDetek2, and the measurement conditions of the gas chromatograph 10 are as follows:

[0118] The detector is a plasma emission detector; the carrier gas is helium with a purity of more than 99.999%; the first chromatographic column 401, the second chromatographic column 402 and the third chromatographic column 403 are mol sieve 5A at a temperature of 60°C; the fourth chromatographic column 404 and the fifth chromatographic column 405 are mol sieve 5A at a temperature of 45°C; the sixth chromatographic column 406 is Hayesep D at a temperature of 60°C; the seventh chromatographic column 407 is Shin Carbon, temperature is 45℃; liquid nitrogen tank 701 is MnCl2 / Al2O3, temperature is -196℃; first quantitative loop 601 is 1mL, second quantitative loop 602 is 1.5mL, third quantitative loop 603 is 1mL, fourth quantitative loop 604 is 1mL; flow rate of first carrier gas 301, second carrier gas 302, fifth carrier gas 305, sixth carrier gas 306, seventh carrier gas 307 and eighth carrier gas 308 is 30mL / min; flow rate of third carrier gas 303 and fourth carrier gas 304 is 20mL / min;

[0119] The sample determination process specifically includes the following steps:

[0120] (1) Sample injection: Start collecting data. At 0 seconds, the gas path diagram is as follows Figure 2 As shown by the red line; the sample gas to be tested is introduced from the sample inlet 101, passes through the No. 4 interface and the No. 3 interface of the first six-way valve 201 in sequence, enters the first quantitative ring 601, and then passes through the No. 6 interface and the No. 5 interface of the first six-way valve 201, flows into the No. 10 interface of the ten-way valve 209, passes through the No. 9 interface of the ten-way valve 209, enters the second quantitative ring 602, and then passes through the No. 2 interface and the No. 1 interface of the ten-way valve 209, flows into the No. 5 interface of the fourth six-way valve 204, passes through the No. 6 interface of the fourth six-way valve 204, enters the third quantitative ring 603, and then passes through the No. 3 interface and the No. 4 interface of the fourth six-way valve 204, flows into the No. 4 interface of the sixth six-way valve 206, passes through the No. 3 interface of the sixth six-way valve 206, enters the fourth quantitative ring 604, and then passes through the No. 6 interface and the No. 5 interface of the sixth six-way valve 206 and then is discharged.

[0121] (2) Detection of O2 and N2:

[0122] Start testing. At 60 seconds, the gas path diagram is as follows: Figure 3 As shown by the red line; the first six-way valve 201 and the second six-way valve 202 are switched to the second state, the carrier gas of the first carrier gas 301 branch pipe passes through the No. 2 interface, the No. 3 interface, the first quantitative ring 601, the No. 6 interface and the No. 1 interface of the first six-way valve 201 in sequence, and flows into the first chromatographic column 401, and the carrier gas brings the sample gas to be tested into the first chromatographic column 401 for pre-separation, and H2 and HD are vented through the No. 2 interface, the No. 3 interface, the No. 5 interface and the No. 4 interface of the second six-way valve 202, and a part of the mixed gas of D2 and O2 is separated;

[0123] At 120 seconds, the gas path diagram is as follows Figure 5 As shown by the red line, the second six-way valve 202 is switched to the first state, and the mixed gas D2 and O2 will flow into the second chromatographic column 402 through the second interface and the first interface of the second six-way valve 202 for separation again;

[0124] At 140 seconds, the gas path diagram is as follows Figure 4 As shown by the red line; the second six-way valve 202 is switched to the second state again, and the second carrier gas 302 connected to the No. 6 interface of the second six-way valve 202 begins to pass the carrier gas to provide power for the second chromatographic column 402 to separate D2 and O2, and the D2 and O2 separated by the second chromatographic column 402 are passed into the No. 2 interface of the third six-way valve 203, and then passed into the first detector 801 through the No. 1 interface to detect the O2 content;

[0125] The sample gas is continuously pre-separated in the first chromatographic column 401 to separate the mixed gas of CH4, CO and a portion of D2, and the mixed gas is discharged through the No. 2 interface, No. 3 interface, No. 5 interface and No. 4 interface of the second six-way valve 202;

[0126] At 265 seconds, the gas path diagram is as follows Figure 5 As shown by the red line, the second six-way valve 202 is switched to the first state, and the sample gas is continuously pre-separated in the first chromatographic column 401, and a part of the mixed gas of D2 and N2 is separated, and the mixed gas will flow into the second chromatographic column 402 through the No. 2 interface and the No. 1 interface of the second six-way valve 202 for separation again, and the D2 and N2 separated by the second chromatographic column 402 are passed into the No. 2 interface of the third six-way valve 203, and then into the first detector 801 through the No. 1 interface to detect the N2 content.

[0127] After the detection of O2 and N2 contents is completed, at 310s, the second six-way valve 202 is switched to the second state, as shown in the gas circuit diagram. Figure 8 As shown by the red line, the gas separated from the first chromatographic column 401 is passed into the No. 2 interface of the second six-way valve 202, and is discharged through the No. 3 interface, the No. 5 interface and the No. 4 interface of the second six-way valve 202 in sequence.

[0128] (3) Detection of H2+HD

[0129] After the detection starts, at 60 seconds, the fourth six-way valve 204 is switched to the second state, and the gas circuit diagram is as follows: Figure 3As shown by the yellow line; the carrier gas of the third carrier gas 303 branch pipe passes through the No. 2 interface, No. 3 interface, the first quantitative ring 601, No. 6 interface and No. 1 interface of the fourth six-way valve 204 in sequence, and flows into the third chromatographic column 403. The carrier gas brings the sample gas into the third chromatographic column 403 for pre-separation, and H2, HD and a small amount of D2 mixed gas are separated. The mixed gas flows into the liquid nitrogen tank 701 through the No. 2 interface and No. 1 interface of the fifth six-way valve 205, and H2 and HD are separated through the MnCl2 / Al2O3 in the liquid nitrogen tank 701, and flows into the second detector 802 to detect the content of H2 and HD. After the detection of the contents of H2 and HD is completed, at the 265th second, the fifth six-way valve 205 is switched to the second state. The gas path diagram is shown in Figure 4 As shown by the yellow line; the gas subsequently separated by the third chromatographic column 403 is passed into the No. 2 interface of the fifth six-way valve 205, and is discharged through the No. 3 interface, No. 5 interface and No. 4 interface of the fifth six-way valve 205 in sequence, and the fourth carrier gas 304 connected to the No. 6 interface of the fifth six-way valve 205 begins to pass the carrier gas to purge the second detector 802.

[0130] (4) Detection of CH4 and CO

[0131] After the detection starts, at 60 seconds, the sixth six-way valve 206 and the seventh six-way valve 207 are switched to the second state, as shown in the gas path diagram. Figure 3 As shown by the green line; the carrier gas of the fifth carrier gas 305 branch pipe passes through the No. 2 interface, No. 3 interface, the fourth quantitative loop, No. 6 interface and No. 1 interface of the sixth six-way valve 206 in sequence, and flows into the fourth chromatographic column 404, the carrier gas brings the sample gas into the fourth chromatographic column 404 for pre-separation, and a part of the mixed gas of H2, HD, D2, O2 and CH4 is separated, and the mixed gas is discharged through the No. 2 interface, No. 3 interface, No. 5 interface and No. 4 interface of the seventh six-way valve 207;

[0132] After a period of time, at 150 seconds, the seventh six-way valve 207 is switched to the first state, and the gas circuit diagram is as shown in FIG. Figure 6 As shown by the green line; the mixed gas will flow into the fifth chromatographic column 405 through the No. 2 interface and the No. 1 interface of the seventh six-way valve 207 for further separation; the CH4 separated by the fifth chromatographic column 405 is passed into the No. 2 interface of the eighth six-way valve 208, and then into the third detector 802 through the No. 1 interface to detect the CH4 content;

[0133] At 175 seconds, the seventh six-way valve 207 is switched to the second state, and the gas circuit diagram is as follows: Figure 4As shown by the green line; a portion of the D2 and N2 mixed gas separated by the fourth chromatographic column 404 is vented through the No. 2 interface, No. 3 interface, No. 5 interface and No. 4 interface of the seventh six-way valve 207, and the sixth carrier gas 306 connected to the No. 6 interface of the seventh six-way valve 207 begins to pass the carrier gas to purge the fifth chromatographic column 405 and the third detector 802;

[0134] At 200 seconds, the seventh six-way valve 207 is switched to the first state again, and the gas circuit diagram is as shown in FIG. Figure 6 As shown by the green line; the CO separated by the fourth chromatographic column 404 will flow into the fifth chromatographic column 405 through the No. 2 interface and the No. 1 interface of the seventh six-way valve 207 for re-separation; the CO separated by the fifth chromatographic column 405 will enter the No. 2 interface of the eighth six-way valve 208, and through the No. 1 interface, it will enter the third detector 802 to detect the CO content.

[0135] At 230 seconds, the seventh six-way valve 207 is switched to the second state again, and the gas circuit diagram is as shown in FIG. Figure 4 As shown by the green line; the remaining impurity mixed gas separated by the fifth chromatographic column 405 is discharged through the No. 2 interface, No. 3 interface, No. 5 interface and No. 4 interface of the seventh six-way valve 207.

[0136] (5) Detection of NMHC and CO2:

[0137] After the detection starts, the ten-way valve 209 is switched to the second state at 290 seconds. The gas circuit diagram is as follows: Figure 7 As shown by the blue line, the carrier gas of the seventh carrier gas 307 branch pipe passes through the No. 3 interface, No. 2 interface, the second quantitative ring 602, No. 9 interface and No. 8 interface of the ten-way valve 209 in sequence, and flows into the sixth chromatographic column 406. The carrier gas brings the sample gas into the sixth chromatographic column 406 for pre-separation. After the pre-separation, the sample gas passes through the No. 4 interface and No. 5 interface of the ten-way valve 209 and flows into the seventh chromatographic column 407. After the sample gas is separated again by the seventh chromatographic column 407, it passes into the No. 6 interface of the eighth six-way valve 208, and is discharged through the No. 5 interface, No. 3 interface and No. 4 interface of the eighth six-way valve 208;

[0138] At 500 seconds, the ten-way valve 209 is switched to the first state, and the gas circuit diagram is as follows: Figure 4As shown by the blue line; the carrier gas of the seventh carrier gas 307 branch pipe is opened and flows into the sixth chromatographic column 406 through the No. 3 interface and the No. 4 interface of the ten-way valve 209 in turn. The carrier gas reverses the mixed gas of the third chromatographic column 403 to pre-separate the non-methane hydrocarbons (NMHC). The separated mixed gas of H2, HD, D2, O2, N2 and CH4 flows out to the third six-way valve 203 through the No. 8 interface and the No. 7 interface of the ten-way valve 209 and passes through the No. 6 interface of the third six-way valve 203. , No. 5 interface, No. 3 interface and No. 4 interface are emptied; the carrier gas of the eighth carrier gas 308 branch pipe is opened and flows into the seventh chromatographic column 407 through the No. 6 interface and No. 5 interface of the ten-way valve 209 in sequence, and the mixed gas in the seventh chromatographic column 407 is pre-separated to separate CO2, and a part of the separated mixed gas of H2, HD, D2, O2, N2 and CH4 flows out to the eighth six-way valve 208, and is emptied through the No. 6 interface, No. 5 interface, No. 3 interface and No. 4 interface of the eighth six-way valve 208;

[0139] At 600 seconds, the third six-way valve 203 is switched to the second state, and the gas circuit diagram is as follows: Fig. 9 As shown by the blue line; the non-methane total hydrocarbons NMHC separated by the sixth chromatographic column 406 pass through the No. 8 and No. 7 interfaces of the ten-way valve 209, flow into the No. 6 interface of the third six-way valve 203, pass through the No. 1 interface, and enter the first detector 801 to detect the content of the non-methane total hydrocarbons NMHC;

[0140] After the third detector 802 completes the detection of CH4 and CO, at 615 seconds, the eighth six-way valve 208 is switched to the second state. Fig.10 As shown by the blue line, the CO2 flowing out of the seventh chromatographic column 407 is passed through the sixth interface and the first interface of the eighth six-way valve 208 and into the third detector 802 to detect the CO2 content.

[0141] The carrier gas is continuously introduced to purge the sample measurement system. The purge time is 1800 seconds, and the sample measurement system is reset.

[0142] Method repeatability determination:

[0143] Standard gases were used to conduct 9 consecutive tests on the MultiDetek2 analyzer. The measurement results were recorded and the relative standard deviation was calculated. The results are shown in Table 1.

[0144] Table 1 Method repeatability test results

[0145]

[0146] From the results in Table 1, it can be seen that the relative standard deviation of the repeatability of the test results is less than 5%, indicating that the repeatability of the method meets the test requirements.

[0147] Detection limit

[0148] Standard gases were used for detection on the MultiDetek2 analytical instrument. The peak height and noise of the analytical instrument were recorded. The detection limit was calculated based on the measurement results. The results are shown in Table 2.

[0149] Table 2 Detection limit detection

[0150]

[0151] From the results in Table 2, it can be seen that the detection limits of oxygen, nitrogen, carbon monoxide, carbon dioxide, methane, non-methane total hydrocarbons, and hydrogen are 0.01 ppmv, and the detection limit of deuterated hydrogen is 1 ppmv.

[0152] It can be seen from the above examples that the method provided by the present invention can quickly and quantitatively separate and determine oxygen, nitrogen, carbon monoxide, carbon dioxide, methane, non-methane total hydrocarbons, hydrogen and deuterated hydrogen in pure deuterium gas with high accuracy and low detection limit.

[0153] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A device for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas, characterized in that: Including sample pretreatment system and sample measurement system; One end of the gas chromatograph air inlet pipeline is connected to the sample pretreatment system, and the other end is connected to the sample measurement system; The sample pretreatment system includes an inert gas source, a standard gas source, a sample source and a vacuum unit connected to the gas chromatograph inlet pipeline; The sample determination system comprises a first detection unit, a second detection unit, a third detection unit and a fourth detection unit which are arranged in parallel and connected in sequence inside the gas chromatograph; The first detection unit is used to detect O2 and N2 impurities in high-purity deuterium gas, the second detection unit is used to detect NMHC and CO2 impurities in high-purity deuterium gas, the third detection unit is used to detect H2 and HD impurities in high-purity deuterium gas, and the fourth detection unit is used to detect CH4 and CO impurities in high-purity deuterium gas.

2. The device for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas according to claim 1, characterized in that: The first detection unit includes a first quantitative ring, the second detection unit includes a second quantitative ring, the third detection unit includes a third quantitative ring, and the fourth detection unit includes a fourth quantitative ring; the first to fourth quantitative rings are connected in sequence through valves and pipelines to form an injection gas path; The first to fourth quantitative rings are used to store the gas to be tested; The first detection unit is provided with a first gas path, and the first quantitative ring is connected to the first gas path; The second detection unit is provided with a second gas circuit, and the second quantitative loop is connected to the second gas circuit; the third detection unit is provided with a third gas circuit, and the third quantitative loop is connected to the third gas circuit; the fourth detection unit is provided with a fourth gas circuit, and the fourth quantitative loop is connected to the fourth gas circuit; the first gas circuit is provided with a first chromatographic column and a second chromatographic column for separating gases, the second gas circuit is provided with a sixth chromatographic column and a seventh chromatographic column for separating gases, the third gas circuit is provided with a third chromatographic column for separating gases, and the fourth gas circuit is provided with a fourth chromatographic column and a fifth chromatographic column for separating gases; the first gas circuit is also provided with a first detector for detecting gas components, the third gas circuit is also provided with a second detector for detecting gas components, and the fourth gas circuit is also provided with a third detector for detecting gas components, and the second gas circuit is connected with the detectors on the third gas circuit and the fourth gas circuit through a connecting pipeline.

3. The device for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas according to claim 2, characterized in that: In the sample determination system, eight groups of six-way valves and one group of ten-way valves for transmitting gas are also included, which are respectively arranged in the first detection unit, the second detection unit, the third detection unit and the fourth detection unit; A first six-way valve, a second six-way valve and a third six-way valve for transmitting gas are provided on the first gas path of the first detection unit; A ten-way valve for transmitting gas is provided on the fourth gas path of the second detection unit; A fourth six-way valve and a fifth six-way valve for transmitting gas are provided on the second gas path of the third detection unit; A sixth six-way valve, a seventh six-way valve and an eighth six-way valve for transmitting gas are provided on the third gas path of the fourth detection unit; The six-way valve and the ten-way valve are both divided into two states, including a first state and a second state; The eight groups of six-way valves are all provided with six interfaces distributed counterclockwise. In the first state, interface No. 1 is connected to interface No. 2, interface No. 3 is connected to interface No. 4, and interface No. 5 is connected to interface No. 6; in the second state, interface No. 1 is connected to interface No. 6, interface No. 2 is connected to interface No. 3, and interface No. 4 is connected to interface No.

5. The ten-way valve is provided with ten interfaces distributed counterclockwise. In the first state, interface No. 1 is connected to interface No. 2, interface No. 3 is connected to interface No. 4, interface No. 5 is connected to interface No. 6, interface No. 7 is connected to interface No. 8, and interface No. 9 is connected to interface No.

10. In the second state, interface No. 1 is connected to interface No. 10, interface No. 2 is connected to interface No. 3, interface No. 4 is connected to interface No. 5, interface No. 6 is connected to interface No. 7, and interface No. 8 is connected to interface No.

9. One end of the first quantitative ring on the first detection unit is connected to the No. 3 interface of the first six-way valve, and the other end is connected to the No. 6 interface of the first six-way valve; One end of the second quantitative ring on the second detection unit is connected to the No. 2 interface of the ten-way valve, and the other end is connected to the No. 9 interface of the ten-way valve; One end of the third quantitative ring on the third detection unit is connected to the No. 3 interface of the fourth six-way valve, and the other end is connected to the No. 6 interface of the fourth six-way valve; One end of the fourth quantitative ring on the fourth detection unit is communicated with the No. 3 interface of the sixth six-way valve, and the other end is communicated with the No. 6 interface of the sixth six-way valve.

4. The device for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas according to claim 3, characterized in that: In the sample measurement system, the sample injection gas circuit includes a first six-way valve, a ten-way valve, a fourth six-way valve and a sixth six-way valve which are connected in sequence; the sample inlet is connected to the No. 4 interface of the first six-way valve, the No. 6 interface of the first six-way valve is connected to the No. 10 interface of the ten-way valve, the No. 1 interface of the ten-way valve is connected to the No. 5 interface of the fourth six-way valve, the No. 4 interface of the fourth six-way valve is connected to the No. 4 interface of the sixth six-way valve, and the No. 5 interface of the sixth six-way valve is connected to the sample outlet.

5. The device for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas according to claim 4, characterized in that: The first gas path on the first detection unit also includes a first carrier gas connected to the No. 2 interface of the first six-way valve, a second carrier gas connected to the No. 6 interface of the second six-way valve; a first vent air resistor connected to the No. 4 interface of the second six-way valve, and a second vent air resistor connected to the No. 4 interface of the third six-way valve; the No. 3 interface of the second six-way valve is connected to the No. 5 interface; one end of the first chromatographic column is connected to the No. 1 interface of the first six-way valve, and the other end is connected to the No. 2 interface of the second six-way valve; one end of the second chromatographic column is connected to the No. 1 interface of the second .... The first end is connected with the No. 2 interface of the third six-way valve, and the first detector is connected with the No. 1 interface of the third six-way valve; the second gas circuit on the second detection unit also includes a seventh carrier gas connected with the No. 3 interface of the ten-way valve, and an eighth carrier gas connected with the No. 6 interface of the ten-way valve; one end of the sixth chromatographic column is connected with the No. 4 interface of the ten-way valve, and the other end is connected with the No. 8 interface of the ten-way valve; one end of the seventh chromatographic column is connected with the No. 5 interface of the ten-way valve, and the other end is connected with the No. 6 interface of the eighth six-way valve; the No. 7 interface of the ten-way valve is connected with the No. 6 interface of the third six-way valve.

6. The device for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas according to claim 5, characterized in that: The third gas circuit on the third detection unit also includes a third carrier gas connected to the No. 2 interface of the fourth six-way valve, a fourth carrier gas connected to the No. 6 interface of the fifth six-way valve; a third vent air resistor connected to the No. 4 interface of the fifth six-way valve; the No. 3 interface of the fifth six-way valve is connected to the No. 5 interface; one end of the third chromatographic column is connected to the No. 1 interface of the fourth six-way valve, and the other end is connected to the No. 2 interface of the fifth six-way valve; the second detector is connected to the No. 1 interface of the fifth six-way valve, and a liquid nitrogen tank is installed on the connecting pipeline.

7. The device for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas according to claim 6, characterized in that: The fourth gas circuit on the fourth detection unit also includes a fifth carrier gas connected to the No. 2 interface of the sixth six-way valve, and a sixth carrier gas connected to the No. 6 interface of the seventh six-way valve; a fourth vent air resistor connected to the No. 4 interface of the seventh six-way valve, and a fifth vent air resistor connected to the No. 4 interface of the eighth six-way valve; the No. 3 interface of the seventh six-way valve is connected to the No. 5 interface; one end of the fourth chromatographic column is connected to the No. 1 interface of the sixth six-way valve, and the other end is connected to the No. 2 interface of the seventh six-way valve; one end of the fifth chromatographic column is connected to the No. 1 interface of the seventh six-way valve, and the other end is connected to the No. 2 interface of the eighth six-way valve; the third detector is connected to the No. 1 interface of the eighth six-way valve.

8. The device for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas according to claim 1, characterized in that: In the sample pretreatment system, the inert gas source connected to the gas chromatograph pipeline includes two groups of pipelines, the first inert gas source and the gas chromatograph are connected along the gas direction of the pipeline, and the first filter, the first pressure reducer and the second pressure reducer are sequentially arranged along the gas direction of the pipeline, and the second inert gas source and the gas chromatograph are connected along the gas direction of the pipeline, and the third pressure reducer, the eighth pneumatic diaphragm valve, the ninth pneumatic diaphragm valve and the mass flow controller are sequentially arranged. One end of the ninth pneumatic diaphragm valve is connected to the mass flow controller, and the other end is respectively connected to the standard gas source, the first sample gas source, the second sample gas source and the vacuum unit; A fourth pressure reducer and a seventh pneumatic diaphragm valve are sequentially arranged along the gas direction of the pipeline connecting the standard gas source and the ninth pneumatic diaphragm valve; A second filter, a first pneumatic diaphragm valve, a fifth pressure reducer and a fifth pneumatic diaphragm valve are sequentially arranged along the gas direction on the pipeline connecting the first sample gas source and the ninth pneumatic diaphragm valve; The second sample gas source is arranged in parallel with the first sample gas source; A tenth pneumatic diaphragm valve is provided on the pipeline connecting the vacuum unit and the ninth pneumatic diaphragm valve; The gas chromatograph is also connected to a fifth pressure sensor in the sample pretreatment system.

9. The device for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas according to claim 8, characterized in that: On the pipeline connecting the first sample gas source and the ninth pneumatic diaphragm valve, the third pneumatic diaphragm valve is connected in parallel at both ends of the fifth pressure reducer; on the pipeline connecting the second sample gas source and the ninth pneumatic diaphragm valve, the fourth pneumatic diaphragm valve is connected in parallel at both ends of the sixth pressure reducer.

10. A method for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas, based on the device for quantitatively detecting trace gas-phase impurities in high-purity deuterium gas according to claims 1-9, characterized in that: The sample pretreatment process is completed by the sample pretreatment system, and the sample determination process is completed by the sample determination system; The sample pretreatment process includes the following steps: S1, pipeline replacement: open the vacuum unit, the tenth pneumatic diaphragm valve, the ninth pneumatic diaphragm valve, the seventh pneumatic diaphragm valve, the fifth pneumatic diaphragm valve, the third pneumatic diaphragm valve, the first pneumatic diaphragm valve, and the mass flow controller opening is set to 100% in sequence. When the pressure of the fifth pressure sensor is ≤-0.095MPa, keep it for 10s, and then close the vacuum unit and the tenth pneumatic diaphragm valve; Open the second inert gas source and the eighth pneumatic diaphragm valve. When the pressure of the fifth pressure sensor is ≥0.2Mpa, keep it for 10s, and then close the second inert gas source and the eighth pneumatic diaphragm valve. Open the vacuum unit and the tenth pneumatic diaphragm valve. When the pressure of the fifth pressure sensor is ≤-0.095Mpa, close the vacuum unit and the tenth pneumatic diaphragm valve. Repeat the pipeline replacement three times, and close the ninth pneumatic diaphragm valve, the seventh pneumatic diaphragm valve, the fifth pneumatic diaphragm valve, the third pneumatic diaphragm valve, and the first pneumatic diaphragm valve in sequence; S2, standard gas replacement pipeline: open the main valve of the standard gas source, and then open the seventh pneumatic diaphragm valve and the ninth pneumatic diaphragm valve in sequence. When the pressure of the fifth pressure sensor is ≥0.1Mpa, keep it for 10s and close the seventh pneumatic diaphragm valve; Open the vacuum unit and the tenth pneumatic diaphragm valve, and when the pressure of the fifth pressure sensor is ≤-0.095Mpa, close the vacuum unit and the tenth pneumatic diaphragm valve; Repeat the standard gas replacement pipeline 3 times; S3, standard gas sampling: open the mass flow controller and set the opening to 10%, open the seventh pneumatic diaphragm valve, when the pressure of the fifth pressure sensor = 0.02Mpa, close the seventh pneumatic diaphragm valve, and start the gas chromatograph to collect data. After 107s, open the vacuum unit and the tenth pneumatic diaphragm valve, open the mass flow controller and set the opening to 100%, when the pressure of the fifth pressure sensor is ≤-0.095Mpa, close the vacuum unit, the tenth pneumatic diaphragm valve and the ninth pneumatic diaphragm valve; the gas chromatograph collects data, and the analysis takes 1800s to complete the detection; S4, sample gas replacement pipeline: open the first sample gas source main valve, open the first pneumatic diaphragm valve, the fifth pneumatic diaphragm valve and the ninth pneumatic diaphragm valve. When the pressure of the fifth pressure sensor is ≥0.1Mpa, keep it for 10s and close the first pneumatic diaphragm valve; Open the vacuum unit and the tenth pneumatic diaphragm valve, and when the pressure of the fifth pressure sensor is ≤-0.095Mpa, close the vacuum unit and the tenth pneumatic diaphragm valve; Repeat the sample gas replacement pipeline 3 times; S5, sample gas injection: open the mass flow controller and set the opening to 10%, open the first pneumatic diaphragm valve, when the pressure of the fifth pressure sensor = 0.02Mpa, close the first pneumatic diaphragm valve, start the gas chromatograph to collect data, open the vacuum unit and the tenth pneumatic diaphragm valve after 107s, open the mass flow controller and set the opening to 100%, when the pressure of the fifth pressure sensor ≤-0.095Mpa, close the vacuum unit, the tenth pneumatic diaphragm valve and the ninth pneumatic diaphragm valve; the gas chromatograph collects data, and the analysis takes 1800s to complete the detection; In steps S3 and S5, when the gas chromatograph is started to collect data, the sample measurement process is completed by the sample measurement system in the gas chromatograph.

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