Octafluoropropane impurity component analysis system and method

Abstract

An octafluoropropane impurity component analysis system and method, relating to the field of gas impurity measurement. Firstly, a first sample loop (3), a second sample loop (13) and a third sample loop (20) are respectively filled with a gas sample; and then, a first carrier gas (10), a first ten-way changeover valve (4), a first gas separation device and a pulsed discharge helium ionization detector (28) are used for measuring the contents of hydrogen, oxygen, argon, nitrogen, methane and carbon monoxide impurity components, a second carrier gas (19) is used for emptying hydrogen-oxygen-argon-nitrogen-methane-carbon monoxide combined peaks which are first separated by a second gas separation device, then a third carrier gas (16) carries later separated carbon dioxide impurity components for content measurement, and a fourth carrier gas (22) empties non-fluorocarbon components which are first separated by a third gas separation device, and then measures the contents of later separated fluorocarbon components. In this way, the main component-octafluoropropane can be back-flushed, thereby completing full analysis of the contents of μmol / mol-level impurity components by means of one-time sample injection.

Description

Octafluoropropane impurity component analysis system and method

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on October 12, 2023, with application number 202311321638.0 and invention name “A system and method for analyzing impurity components of octafluoropropane”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the field of gas impurity detection, and in particular to an octafluoropropane impurity component analysis system and method. Background Art

[0003] Currently, GB / T31986-2015 "Octafluoropropane Gas for Electronics Industry" stipulates that the purity volume fraction of octafluoropropane (C3F8) is greater than or equal to 99.999% (or 99.99%), and the impurity component content in octafluoropropane is between 0.1 and 5 μmol / mol (or 0.1 to 50 μmol / mol). Therefore, in order to meet the purity requirements of octafluoropropane, it is necessary to develop a system or method for detecting the impurity component content at the μmol / mol level.

[0004] Summary of the Invention

[0005] The purpose of the present invention is to provide an octafluoropropane impurity component analysis system and method, which can backflush out the main component octafluoropropane and complete the full analysis of the impurity component content at the μmol / mol level in one injection.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] An octafluoropropane impurity component analysis system, comprising: a first ten-way switching valve, a first quantitative loop, a 20-way switching valve, a second quantitative loop, a six-way switching valve, a third quantitative loop, a first gas separation device, a pulse discharge helium ionization detector, a second gas separation device, and a third gas separation device;

[0008] Port 1 of the first ten-way switching valve is the gas sample inlet, port 10 of the first ten-way switching valve is connected to one end of the first quantitative loop, and port 3 of the first ten-way switching valve is connected to the other end of the first quantitative loop; port 1 of the 20-way switching valve is connected to port 2 of the first ten-way switching valve, port 10 of the 20-way switching valve is connected to one end of the second quantitative loop, and port 3 of the 20-way switching valve is connected to the other end of the second quantitative loop; port 1 of the six-way switching valve is connected to port 2 of the 20-way switching valve, port 6 of the six-way switching valve is connected to one end of the third quantitative loop, and port 3 of the six-way switching valve is connected to the other end of the third quantitative loop; the gas sample is an octafluoropropane sample containing impurity components;

[0009] Port 4 of the first ten-way switching valve is a first carrier gas inlet, one end of the first gas separation device is connected to port 9 of the first ten-way switching valve, and the other end of the first gas separation device is connected to a pulse discharge helium ionization detector; the pulse discharge helium ionization detector is used to detect the content of hydrogen, oxygen, argon, nitrogen, methane and carbon monoxide impurity components separated from the gas sample by the first gas separation device;

[0010] Port 4 of the 20th-way switching valve is the second carrier gas inlet, port 7 of the 20th-way switching valve is the third carrier gas inlet, one end of the second gas separation device is connected to port 9 of the 20th-way switching valve, and the other end of the second gas separation device is connected to a pulse discharge helium ionization detector; after the second carrier gas evacuates the hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide peak first separated by the second gas separation device, the third carrier gas carries the carbon dioxide impurity component separated by the second gas separation device into the pulse discharge helium ionization detector for content detection;

[0011] Port No. 5 of the six-way switching valve is the fourth carrier gas inlet, one end of the third gas separation device is connected to port No. 4 of the six-way switching valve, and the other end of the third gas separation device is connected to the pulse discharge helium ionization detector; the fourth carrier gas empties the non-fluorocarbon components first separated by the third gas separation device, and then carries the fluorocarbon components separated by the third gas separation device into the pulse discharge helium ionization detector for content detection; the fluorocarbon components include carbon tetrafluoride, hexafluoroethane, hexafluoropropylene, heptafluoropropane and octafluorocyclobutane.

[0012] A method for analyzing impurity components of octafluoropropane, comprising:

[0013] Gas sample sampling stage:

[0014] The interface states of the first ten-way switching valve and the second ten-way switching valve are both set to the first connection mode, and the interface state of the six-way switching valve is set to the first connection state; the first connection mode is that port 1 of the ten-way switching valve is connected to port 10, port 2 is connected to port 3, port 4 is connected to port 5, port 6 is connected to port 7, and port 8 is connected to port 9; the first connection state is that port 1 of the six-way switching valve is connected to port 6, port 2 is connected to port 3, and port 4 is connected to port 5;

[0015] A gas sample is introduced from port 1 of the first ten-way switching valve so that the first quantitative loop, the second quantitative loop, and the third quantitative loop are all filled with equal amounts of the gas sample; the gas sample is an octafluoropropane gas sample containing impurity components;

[0016] Hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide component detection stage:

[0017] Switch the interface state of the first ten-way switching valve to the second connection mode; the second connection mode is that port 1 of the ten-way switching valve is connected to port 2, port 3 is connected to port 4, port 5 is connected to port 6, port 7 is connected to port 8, and port 9 is connected to port 10;

[0018] The first carrier gas is introduced from port 4 of the first ten-way switching valve. The first carrier gas carries the gas sample in the first quantitative loop into the first gas separation device, and after being separated into hydrogen, oxygen, argon, nitrogen, methane and carbon monoxide impurity components by the first gas separation device, enters the pulse discharge helium ionization detector for content detection;

[0019] Carbon dioxide composition detection stage:

[0020] Switching the interface state of the 20th-way switching valve to the second connection mode;

[0021] A second carrier gas is introduced from port 4 of the 20th-way switching valve. The second carrier gas carries the gas sample in the second quantitative loop into the second gas separation device. After the combined peak of hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide first separated by the second gas separation device is evacuated, the interface state of the 20th-way switching valve is switched to the first connection mode.

[0022] The third carrier gas is introduced from port 7 of the 20th-way switching valve. The third carrier gas carries the carbon dioxide impurity components separated by the second gas separation device and enters the pulse discharge helium ionization detector for content detection.

[0023] Fluorocarbon component detection stage:

[0024] Switch the interface state of the six-way switching valve to the second connection state; the second connection state is that port 1 of the six-way switching valve is connected to port 2, port 3 is connected to port 4, and port 5 is connected to port 6;

[0025] A fourth carrier gas is introduced from port 5 of the six-way switching valve. The fourth carrier gas carries the gas sample in the third quantitative loop into the third gas separation device. After the non-fluorocarbon components first separated by the third gas separation device are evacuated, the interface state of the six-way switching valve is switched to the first connection state.

[0026] The fourth carrier gas carries the fluorocarbon components separated by the third gas separation device into a pulse discharge helium ionization detector for content detection; the fluorocarbon components include carbon tetrafluoride, hexafluoroethane, hexafluoropropylene, heptafluoropropane and octafluorocyclobutane.

[0027] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0028] The present invention discloses an octafluoropropane impurity component analysis system and method. First, a first quantitative loop, a second quantitative loop, and a third quantitative loop are all filled with a gas sample. Then, a first carrier gas, a first ten-way switching valve, a first gas separation device, and a pulsed discharge helium ionization detector are used to detect the content of hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide impurity components. After the second carrier gas is used to exhaust the combined peak of hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide first separated by the second gas separation device, the third carrier gas carries the carbon dioxide impurity component separated after the second gas separation device into the pulsed discharge helium ionization detector for content detection. After the fourth carrier gas is used to exhaust the non-fluorocarbon components first separated by the third gas separation device, the fluorocarbon components separated after the third gas separation device are carried into the pulsed discharge helium ionization detector for content detection. The present invention can backflush away the main component octafluoropropane, and complete the full analysis of the impurity component content at the μmol / mol level in a single injection.

[0029] Figures in the specification

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0031] FIG1 is a connection diagram of an octafluoropropane impurity component analysis system in a gas sample sampling stage provided by an embodiment of the present invention;

[0032] FIG2 is a connection diagram of an octafluoropropane impurity component analysis system provided by an embodiment of the present invention in the hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide component detection stage;

[0033] FIG3 is a connection diagram of an octafluoropropane impurity component analysis system in a carbon dioxide component detection stage provided by an embodiment of the present invention;

[0034] FIG4 is a connection diagram of an octafluoropropane impurity component analysis system provided by an embodiment of the present invention in the fluorocarbon component detection stage.

[0035] Explanation of symbols: 1-sample storage tank, 2-first pressure reducing valve, 3-first quantitative loop, 4-first ten-way switching valve, 5-first polymer chromatography column, 6-first needle valve, 7-molecular sieve chromatography column, 8-fifth carrier gas line, 9-second plane tee, 10-first carrier gas line, 11-third plane tee, 12-twentieth-way switching valve, 13-second quantitative loop, 14-second polymer chromatography column, 15-third polymer chromatography column, 16-third carrier gas line, 17-fourth plane tee, 18-second Needle valve, 19-second carrier gas line, 20-third quantitative loop, 21-six-way switching valve, 22-fourth carrier gas line, 23-metering device, 24-first capillary chromatographic column, 25-flat four-way, 26-second pressure reducing valve, 27-carrier gas device, 28-pulsed discharge helium ionization detector, 29-second four-way switching valve, 30-third needle valve, 31-first flat three-way, 32-sixth carrier gas line, 33-fourth needle valve, 34-first four-way switching valve, 35-second capillary chromatographic column. DETAILED DESCRIPTION

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0037] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] As shown in Figure 1, an embodiment of the present invention provides an octafluoropropane impurity component analysis system, including: a first ten-way switching valve 4, a first quantitative ring 3, a twentieth-way switching valve 12, a second quantitative ring 13, a six-way switching valve 21, a third quantitative ring 20, a first gas separation device, a pulse discharge helium ionization detector 28, a second gas separation device and a third gas separation device.

[0039] Port No. 1 of the first ten-way switching valve 4 is the gas sample inlet, port No. 10 of the first ten-way switching valve 4 is connected to one end of the first quantitative ring 3, and port No. 3 of the first ten-way switching valve 4 is connected to the other end of the first quantitative ring 3; port No. 1 of the twentieth-way switching valve 12 is connected to port No. 2 of the first ten-way switching valve 4, port No. 10 of the twentieth-way switching valve 12 is connected to one end of the second quantitative ring 13, and port No. 3 of the twentieth-way switching valve 12 is connected to the other end of the second quantitative ring 13; port No. 1 of the six-way switching valve 21 is connected to port No. 2 of the twentieth-way switching valve 12, port No. 6 of the six-way switching valve 21 is connected to one end of the third quantitative ring 20, and port No. 3 of the six-way switching valve 21 is connected to the other end of the third quantitative ring 20; the gas sample is an octafluoropropane sample containing impurity components.

[0040] Port No. 4 of the first ten-way switching valve 4 is the first carrier gas inlet, one end of the first gas separation device is connected to port No. 9 of the first ten-way switching valve 4, and the other end of the first gas separation device is connected to the pulse discharge helium ionization detector 28; the pulse discharge helium ionization detector 28 is used to detect the content of hydrogen, oxygen, argon, nitrogen, methane and carbon monoxide impurity components separated from the gas sample by the first gas separation device.

[0041] Port No. 4 of the 20th-way switching valve 12 is the second carrier gas inlet, and port No. 7 of the 20th-way switching valve 12 is the third carrier gas inlet. One end of the second gas separation device is connected to port No. 9 of the 20th-way switching valve 12, and the other end of the second gas separation device is connected to the pulse discharge helium ionization detector 28; after the second carrier gas empties the hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide peak first separated by the second gas separation device, the third carrier gas carries the carbon dioxide impurity component separated by the second gas separation device into the pulse discharge helium ionization detector 28 for content detection.

[0042] Port No. 5 of the six-way switching valve 21 is the fourth carrier gas inlet, one end of the third gas separation device is connected to port No. 4 of the six-way switching valve 21, and the other end of the third gas separation device is connected to the pulse discharge helium ionization detector 28; the fourth carrier gas empties the non-fluorocarbon components first separated by the third gas separation device, and then carries the fluorocarbon components separated by the third gas separation device into the pulse discharge helium ionization detector 28 for content detection; the fluorocarbon components include carbon tetrafluoride, hexafluoroethane, hexafluoropropylene, heptafluoropropane and octafluorocyclobutane.

[0043] In one example, the first gas separation device includes: a first polymer chromatography column 5 and a molecular sieve chromatography column 7 .

[0044] One end of the first polymer chromatography column 5 is connected to port 9 of the first ten-way switching valve 4, and the other end of the first polymer chromatography column 5 is connected to port 6 of the first ten-way switching valve 4. The first polymer chromatography column 5 is used to sequentially separate the combined peak of hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide from the gas sample, and the combined peaks other than hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide. One end of the molecular sieve chromatography column 7 is connected to port 5 of the first ten-way switching valve 4, and the other end of the molecular sieve chromatography column 7 is connected to a pulsed discharge helium ionization detector 28. The molecular sieve chromatography column 7 is used to separate the combined peak of hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide into hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide.

[0045] In another example, the second gas separation device includes: a second polymer chromatography column 14 and a third polymer chromatography column 15 .

[0046] One end of the second polymer chromatography column 14 is connected to port 9 of the 20th-port switching valve 12, and the other end is connected to port 6 of the 20th-port switching valve 12. The second polymer chromatography column 14 is used to sequentially separate the hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide peaks, the carbon dioxide component, and the heavy components from the gas sample. One end of the third polymer chromatography column 15 is connected to port 8 of the 20th-port switching valve 12, and the other end is connected to the pulsed discharge helium ionization detector 28. The third polymer chromatography column 15 is used to further separate carbon dioxide from the carbon dioxide component.

[0047] In yet another example, the third gas separation device includes: a first capillary chromatographic column 24 , a second capillary chromatographic column 35 and a first four-way switching valve 34 .

[0048] One end of the first capillary column 24 is connected to port 4 of the six-way switching valve 21, and the other end is connected to port 1 of the first four-way switching valve 34. One end of the second capillary column 35 is connected to port 2 of the first four-way switching valve 34, and the other end is connected to the pulsed discharge helium ionization detector 28. The first capillary column 24 is used to sequentially separate non-fluorocarbon components and fluorocarbon components from the gas sample. The first four-way switching valve 34 is used to connect ports 1 and 4 to completely vent the non-fluorocarbon components, and then switch to connect ports 1 and 2 to transfer the fluorocarbon components to the second capillary column 35. The second capillary column 35 is used to separate the fluorocarbon components into tetrafluoromethane, hexafluoroethane, hexafluoropropylene, heptafluoropropane, and octafluorocyclobutane.

[0049] The interior of the molecular sieve chromatography column 7 is filled with 5A chromatography support or other equivalent chromatography supports.

[0050] The first polymer chromatography column 5 , the second polymer chromatography column 14 , and the third polymer chromatography column 15 are filled with porapak Q chromatography support or other equivalent chromatography supports.

[0051] The first capillary chromatographic column 24 and the second capillary chromatographic column 35 are Gas-pro capillary columns or other equivalent chromatographic columns.

[0052] 1 , the analysis system further includes a second four-way switching valve 29 and a first planar three-way valve 31 .

[0053] The other end of the first gas separation device is connected to port 4 of the second four-way switching valve 29, and port 1 of the second four-way switching valve 29 is connected to the pulse discharge helium ionization detector 28. The first port of the first planar tee 31 is connected to port 2 of the second four-way switching valve 29, the second port of the first planar tee 31 is connected to the other end of the second gas separation device, and the third port of the first planar tee 31 is connected to the other end of the third gas separation device.

[0054] The analysis system further includes a first needle valve 6, a second needle valve 18, a third needle valve 30, and a fourth needle valve 33. The first needle valve 6 is connected to port 8 of the first ten-way switching valve 4. The second needle valve 18 is connected to port 5 of the 20-way switching valve 12. The third needle valve 30 is connected to port 3 of the second four-way switching valve 29. The fourth needle valve 33 is connected to port 4 of the first four-way switching valve 34.

[0055] The analysis system also includes: a sample storage tank 1, a first pressure reducing valve 2, and a metering device 23. The gas output end of the sample storage tank 1 is connected to port 1 of the first ten-way switching valve 4 through the first pressure reducing valve 2; the metering device 23 is connected to port 2 of the six-way switching valve 21. The sample storage tank 1 is used to reduce the pressure of the stored gas sample through the first pressure reducing valve 2, and then flow through the first ten-way switching valve 4, the first quantitative ring 3, the 20-way switching valve 12, the second quantitative ring 13, the six-way switching valve 21, the third quantitative ring 20, and the metering device 23 in sequence, so that the first quantitative ring 3, the second quantitative ring 13, and the third quantitative ring 20 are all filled with the gas sample at a preset flow rate or preset pressure.

[0056] The metering device 23 is a flow meter or a pressure sensor.

[0057] The analysis system further includes: a gas carrier device 27 , a second pressure reducing valve 26 , a second planar tee 9 , a third planar tee 11 , a fourth planar tee 17 and a planar cross 25 .

[0058] The carrier gas device 27 is connected to the first port of the second planar tee 9 through the second pressure reducing valve 26. The second port of the second planar tee 9 is connected to port 7 of the first ten-way switching valve 4. The third port of the second planar tee 9 is connected to the first port of the third planar tee 11. The second port of the third planar tee 11 is connected to port 4 of the first ten-way switching valve 4. The third port of the third planar tee 11 is connected to the first port of the fourth planar tee 17. The second port of the fourth planar tee 17 is connected to port 7 of the 20-way switching valve 12. The third port of the fourth planar tee 17 is connected to the first port of the planar four-way 25. The second port of the planar four-way 25 is connected to port 4 of the 20-way switching valve 12. The third port of the planar four-way 25 is connected to port 5 of the six-way switching valve 21. The fourth port of the planar four-way 25 is connected to port 3 of the first four-way switching valve 34.

[0059] The basic principles of an octafluoropropane impurity component analysis system provided by an embodiment of the present invention are as follows:

[0060] The carrier gas flow process includes:

[0061] After flowing out of the carrier gas device 27, the carrier gas is reduced in pressure through the second pressure reducing valve 26 → the first interface of the second planar tee 9 → the fifth carrier gas pipeline 8 → port No. 7 of the first ten-way switching valve 4, port No. 6 of the first ten-way switching valve 4, the first polymer chromatography column 5, port No. 9 of the first ten-way switching valve 4, port No. 8 of the first ten-way switching valve 4, and the first needle valve 6.

[0062] The carrier gas flowing out from the second interface of the second plane tee 9 → the first interface of the third plane tee 11 → the first carrier gas pipeline 10 → port No. 4 of the first ten-way switching valve 4, port No. 5 of the first ten-way switching valve 4, molecular sieve chromatography column 7 → port No. 4 of the second four-way switching valve 29, port No. 1 of the second four-way switching valve 29, and pulse discharge helium ionization detector 28.

[0063] The second interface of the third plane tee 11 → the first interface of the fourth plane tee 17 → the third carrier gas pipeline 16 → port No. 7 of the twentieth-way switching valve 12, port No. 6 of the twentieth-way switching valve 12, the second polymer chromatography column 14, port No. 9 of the twentieth-way switching valve 12, port No. 8 of the twentieth-way switching valve 12, the third polymer chromatography column 15 → an interface of the first plane tee 31 → port No. 2 of the second four-way switching valve 29, port No. 3 of the second four-way switching valve 29, the third needle valve 30.

[0064] The third interface of the fourth planar tee 17 → the first interface of the planar cross 25 → the second carrier gas pipeline 19 → the No. 4 port of the 20th-way switching valve 12, the No. 5 port of the 20th-way switching valve 12, and the second needle valve 18.

[0065] The third interface of the planar four-way valve 25 → the fourth carrier gas line 22 → port 5 of the six-way switching valve 21, port 4 of the six-way switching valve 21, the first capillary chromatographic column 24 → ports 1 and 4 of the first four-way switching valve 34, and the fourth needle valve 33.

[0066] The fourth interface of the planar four-way valve 25 → the sixth carrier gas line 32 → port 3 of the first four-way switching valve 34 , port 2 of the first four-way switching valve 34 , the second capillary chromatographic column 35 → one interface of the first planar three-way valve 31 .

[0067] Sampling process:

[0068] The sample flows out of the sample storage tank 1 and is reduced in pressure through the first pressure-reducing valve 2 → port 1 of the first ten-way switching valve 4, port 10 of the first ten-way switching valve 4, the first quantitative loop 3, port 3 of the first ten-way switching valve 4, and port 2 of the first ten-way switching valve 4 → port 1 of the 20-way switching valve 12, port 10 of the 20-way switching valve 12, the second quantitative loop 13, port 3 of the 20-way switching valve 12, and port 2 of the 20-way switching valve 12 → port 1 of the six-way switching valve 21, port 6 of the six-way switching valve 21, the third quantitative loop 20, port 3 of the six-way switching valve 21, and port 2 of the six-way switching valve 21 → a flow meter or a pressure sensor.

[0069] Analysis and testing process:

[0070] Hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide component analysis and detection process:

[0071] As shown in Figure 2, the first carrier gas carries the sample in the first quantitative loop 3 into the first polymer chromatography column 5, and is pre-separated into a hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide combined peak and a combined peak other than hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide components. When the hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide combined peak completely enters the molecular sieve chromatography column 7 from the first polymer chromatography column 5, the first ten-way switching valve 4 is reset to the state of Figure 1, and the hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide combined peak is further separated into hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide components by the molecular sieve chromatography column 7, while the combined peak other than hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide components are backflushed by the fifth carrier gas and released by the first needle valve 6.

[0072] Carbon dioxide component analysis and detection process:

[0073] As shown in FIG2 , the second carrier gas carries the sample in the second quantitative loop 13 into the second polymer chromatography column 14 for pre-separation into light components (such as hydrogen, oxygen, argon, and nitrogen), carbon dioxide components, and heavy components (such as hydrocarbons above C2).

[0074] When the light components (such as hydrogen, oxygen, argon, and nitrogen) are completely discharged by the second needle valve 18, the 20th-way switching valve 12 is switched to the state shown in Figure 3 , and the third carrier gas carrying the carbon dioxide component in the second polymer chromatography column 14 enters the third polymer chromatography column 15, where it is further separated into the carbon dioxide component, which is detected by the pulsed discharge helium ionization detector 28. When the carbon dioxide component has completely entered the third polymer chromatography column 15, the second four-way switching valve 29 is switched to the state shown in Figure 2 , and the third carrier gas carrying the heavy components in the third polymer chromatography column 15 is discharged by the third needle valve 30.

[0075] Fluorocarbon component analysis and testing process:

[0076] As shown in FIG2 , the fourth carrier gas carries the sample in the third quantitative loop 20 into the pre-analysis first capillary chromatographic column 24 and is separated into non-fluorocarbon components and fluorocarbon components. When the non-fluorocarbon components are completely discharged by the fourth needle valve 33 , the first four-way switching valve 34 is switched to the state shown in FIG4 , and the fluorocarbon components are further separated into tetrafluoromethane, hexafluoroethane, hexafluoropropylene, heptafluoropropane, and octafluorocyclobutane components by the second capillary chromatographic column 35 and detected by the pulse discharge helium ionization detector 28 .

[0077] The octafluoropropane impurity component analysis system of the present invention adopts a heart-cutting analysis system to back-flush the main component octafluoropropane (C3F8) to detect the μmol / mol level impurity component content therein.

[0078] The present invention also provides a method for analyzing impurity components of octafluoropropane, comprising:

[0079] Gas sample sampling stage:

[0080] The interface states of the first ten-way switching valve 4 and the second ten-way switching valve 12 are both set to the first connection mode, and the interface state of the six-way switching valve 21 is set to the first connection state; the first connection mode is that port No. 1 of the ten-way switching valve is connected with port No. 10, port No. 2 is connected with port No. 3, port No. 4 is connected with port No. 5, port No. 6 is connected with port No. 7, and port No. 8 is connected with port No. 9; the first connection state is that port No. 1 of the six-way switching valve 21 is connected with port No. 6, port No. 2 is connected with port No. 3, and port No. 4 is connected with port No. 5.

[0081] A gas sample is introduced from port 1 of the first ten-way switching valve 4 so that the first quantitative ring 3, the second quantitative ring 13 and the third quantitative ring 20 are all filled with equal amounts of the gas sample; the gas sample is an octafluoropropane gas sample containing impurity components.

[0082] Hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide component detection stage:

[0083] Switch the interface state of the first ten-way switching valve 4 to the second connection mode; the second connection mode is that port 1 of the ten-way switching valve is connected to port 2, port 3 is connected to port 4, port 5 is connected to port 6, port 7 is connected to port 8, and port 9 is connected to port 10.

[0084] The first carrier gas is introduced from port No. 4 of the first ten-way switching valve 4. The first carrier gas carries the gas sample in the first quantitative ring 3 into the first gas separation device, and after being separated into hydrogen, oxygen, argon, nitrogen, methane and carbon monoxide impurity components by the first gas separation device, enters the pulse discharge helium ionization detector 28 for content detection.

[0085] Carbon dioxide composition detection stage:

[0086] Switch the interface state of the twentieth-way switching valve 12 to the second connection mode; the second connection mode is that port 1 of the ten-way switching valve is connected with port 2, port 3 is connected with port 4, port 5 is connected with port 6, port 7 is connected with port 8, and port 9 is connected with port 10.

[0087] The second carrier gas is introduced from port No. 4 of the 20th-way switching valve 12. The second carrier gas carries the gas sample in the second quantitative ring 13 into the second gas separation device. After the hydrogen, oxygen, argon, nitrogen, methane and carbon monoxide peak first separated by the second gas separation device is emptied, the interface state of the 20th-way switching valve 12 is switched to the first connection mode.

[0088] The third carrier gas is introduced from port 7 of the 20th-way switching valve 12. The third carrier gas carries the carbon dioxide impurity component separated by the second gas separation device and enters the pulse discharge helium ionization detector 28 for content detection.

[0089] Fluorocarbon component detection stage:

[0090] The interface state of the six-way switching valve 21 is switched to the second connection state; the second connection state is that port 1 of the six-way switching valve 21 is connected to port 2, port 3 is connected to port 4, and port 5 is connected to port 6.

[0091] The fourth carrier gas is introduced from port No. 5 of the six-way switching valve 21. The fourth carrier gas carries the gas sample in the third quantitative ring 20 into the third gas separation device. After the non-fluorocarbon components first separated by the third gas separation device are emptied, the interface state of the six-way switching valve 21 is switched to the first connection state.

[0092] The fourth carrier gas carries the fluorocarbon components separated by the third gas separation device into the pulse discharge helium ionization detector 28 for content detection; the fluorocarbon components include carbon tetrafluoride, hexafluoroethane, hexafluoropropylene, heptafluoropropane and octafluorocyclobutane.

[0093] There is no restriction on the detection order of the hydrogen, oxygen, argon, nitrogen, methane, carbon monoxide component detection stage, the carbon dioxide component detection stage and the fluorocarbon component detection stage, and they can be carried out simultaneously or in sequence.

[0094] The octafluoropropane impurity component analysis system provided in the embodiment of the present invention can execute an octafluoropropane impurity component analysis method, and the detailed operation process of the octafluoropropane impurity component analysis system when executing the method can be found in the introduction of the sampling process and the analysis and detection process.

[0095] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. The methods disclosed in the embodiments are described briefly because they correspond to the systems disclosed in the embodiments. For relevant details, refer to the method description.

[0096] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. An octafluoropropane impurity component analysis system, characterized in that: The analysis system comprises: a first ten-way switching valve, a first quantitative ring, a twentieth-way switching valve, a second quantitative ring, a six-way switching valve, a third quantitative ring, a first gas separation device, a pulse discharge helium ionization detector, a second gas separation device and a third gas separation device; Port No. 1 of the first ten-way switching valve is the gas sample inlet, port No. 10 of the first ten-way switching valve is connected to one end of the first quantitative ring, and port No. 3 of the first ten-way switching valve is connected to the other end of the first quantitative ring; port No. 1 of the twentieth-way switching valve is connected to port No. 2 of the first ten-way switching valve, port No. 10 of the twentieth-way switching valve is connected to one end of the second quantitative ring, and port No. 3 of the twentieth-way switching valve is connected to the other end of the second quantitative ring; port No. 1 of the six-way switching valve is connected to port No. 2 of the twentieth-way switching valve, port No. 6 of the six-way switching valve is connected to one end of the third quantitative ring, and port No. 3 of the six-way switching valve is connected to the other end of the third quantitative ring; the gas sample is an octafluoropropane sample containing impurity components; Port No. 4 of the first ten-way switching valve is a first carrier gas inlet, one end of the first gas separation device is connected to port No. 9 of the first ten-way switching valve, and the other end of the first gas separation device is connected to a pulse discharge helium ionization detector; the pulse discharge helium ionization detector is used to detect the content of hydrogen, oxygen, argon, nitrogen, methane and carbon monoxide impurity components separated from the gas sample by the first gas separation device; Port No. 4 of the 20th-way switching valve is the second carrier gas inlet, port No. 7 of the 20th-way switching valve is the third carrier gas inlet, one end of the second gas separation device is connected to port No. 9 of the 20th-way switching valve, and the other end of the second gas separation device is connected to the pulse discharge helium ionization detector; after the second carrier gas empties the hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide combined peak first separated by the second gas separation device, the third carrier gas carries the carbon dioxide impurity component separated by the second gas separation device into the pulse discharge helium ionization detector for content detection; Port No. 5 of the six-way switching valve is the fourth carrier gas inlet, one end of the third gas separation device is connected to port No. 4 of the six-way switching valve, and the other end of the third gas separation device is connected to the pulse discharge helium ionization detector; the fourth carrier gas empties the non-fluorocarbon components first separated by the third gas separation device, and then carries the fluorocarbon components separated by the third gas separation device into the pulse discharge helium ionization detector for content detection; the fluorocarbon components include carbon tetrafluoride, hexafluoroethane, hexafluoropropylene, heptafluoropropane and octafluorocyclobutane.

2. The octafluoropropane impurity component analysis system according to claim 1, characterized in that: The first gas separation device comprises: a first polymer chromatography column and a molecular sieve chromatography column; One end of the first polymer chromatography column is connected to port 9 of the first ten-way switching valve, and the other end of the first polymer chromatography column is connected to port 6 of the first ten-way switching valve; the first polymer chromatography column is used to sequentially separate the combined peak of hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide and the combined peak other than the hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide components from the gas sample; One end of the molecular sieve chromatographic column is connected to port No. 5 of the first ten-way switching valve, and the other end of the molecular sieve chromatographic column is connected to a pulse discharge helium ionization detector; the molecular sieve chromatographic column is used to separate the combined peak of hydrogen, oxygen, argon, nitrogen, methane and carbon monoxide into hydrogen, oxygen, argon, nitrogen, methane and carbon monoxide.

3. The octafluoropropane impurity component analysis system according to claim 1, characterized in that: The second gas separation device comprises: a second polymer chromatography column and a third polymer chromatography column; One end of the second polymer chromatography column is connected to port 9 of the 20th-way switching valve, and the other end of the second polymer chromatography column is connected to port 6 of the 20th-way switching valve; the second polymer chromatography column is used to sequentially separate the hydrogen, oxygen, argon, nitrogen, methane, carbon monoxide combined peak, carbon dioxide component and heavy component from the gas sample; One end of the third polymer chromatography column is connected to port 8 of the 20th-way switching valve, and the other end of the third polymer chromatography column is connected to a pulse discharge helium ionization detector; the third polymer chromatography column is used to further separate carbon dioxide from the carbon dioxide component.

4. The octafluoropropane impurity component analysis system according to claim 1, characterized in that: The third gas separation device comprises: a first capillary chromatographic column, a second capillary chromatographic column and a first four-way switching valve; One end of the first capillary chromatographic column is connected to port 4 of the six-way switching valve, and the other end of the first capillary chromatographic column is connected to port 1 of the first four-way switching valve; one end of the second capillary chromatographic column is connected to port 2 of the first four-way switching valve, and the other end of the second capillary chromatographic column is connected to a pulse discharge helium ionization detector; The first capillary chromatographic column is used to sequentially separate non-fluorocarbon components and fluorocarbon components from the gas sample; the first four-way switching valve is used to connect port 1 with port 4 to completely vent the non-fluorocarbon components, and then switch to connect port 1 with port 2 to transfer the fluorocarbon components to the second capillary chromatographic column; the second capillary chromatographic column is used to separate the fluorocarbon components into four Fluorinated carbons, hexafluoroethane, hexafluoropropylene, heptafluoropropane and octafluorocyclobutane.

5. The octafluoropropane impurity component analysis system according to claim 4, characterized in that: The analysis system further comprises: a second four-way switching valve and a first plane three-way valve; The other end of the first gas separation device is connected to port No. 4 of the second four-way switching valve, and port No. 1 of the second four-way switching valve is connected to a pulse discharge helium ionization detector; The first interface of the first plane tee is connected to port 2 of the second four-way switching valve, the second interface of the first plane tee is connected to the other end of the second gas separation device, and the third interface of the first plane tee is connected to the other end of the third gas separation device.

6. The octafluoropropane impurity component analysis system according to claim 5, characterized in that: The analysis system further comprises: a first needle valve, a second needle valve, a third needle valve and a fourth needle valve; The first needle valve is connected to port No. 8 of the first ten-way switching valve; The second needle valve is connected to port 5 of the 20th-way switching valve; The third needle valve is connected to port 3 of the second four-way switching valve; The fourth needle valve is connected to port No. 4 of the first four-way switching valve.

7. The octafluoropropane impurity component analysis system according to claim 1, characterized in that: The analysis system further comprises: a sample storage tank, a first pressure reducing valve and a metering device; The gas output end of the sample storage tank is connected to the No. 1 port of the first ten-way switching valve through the first pressure reducing valve; the metering device is connected to the No. 2 port of the six-way switching valve; The sample storage tank is used to reduce the pressure of the stored gas sample through the first pressure reducing valve, and then flow through the first ten-way switching valve, the first quantitative ring, the twentieth-way switching valve, the second quantitative ring, the six-way switching valve, the third quantitative ring and the metering device in sequence, so that the first quantitative ring, the second quantitative ring and the third quantitative ring are all filled with the gas sample with a preset flow rate or a preset pressure.

8. The octafluoropropane impurity component analysis system according to claim 7, characterized in that: The metering device is a flow meter or a pressure sensor.

9. The octafluoropropane impurity component analysis system according to claim 4, characterized in that: The analysis system further comprises: a gas carrier device, a second pressure reducing valve, a second planar tee, a third planar tee, a fourth planar tee and a planar cross; The gas carrier device is connected to the first interface of the second plane tee through the second pressure reducing valve, the second interface of the second plane tee is connected to the No. 7 port of the first ten-way switching valve, and the third interface of the second plane tee is connected to the first interface of the third plane tee; The second interface of the third plane tee is connected to the No. 4 port of the first ten-way switching valve, and the third interface of the third plane tee is connected to the first interface of the fourth plane tee; The second interface of the fourth plane tee is connected to the No. 7 port of the twentieth-way switching valve, and the third interface of the fourth plane tee is connected to the first interface of the plane cross; The second interface of the planar four-way is connected to port 4 of the twentieth-way switching valve, the third interface of the planar four-way is connected to port 5 of the six-way switching valve, and the fourth interface of the planar four-way is connected to port 3 of the first four-way switching valve.

10. A method for analyzing impurity components of octafluoropropane, characterized in that: include: Gas sample sampling stage: The interface states of the first ten-way switching valve and the second ten-way switching valve are both set to the first connection mode, and the interface state of the six-way switching valve is set to the first connection state; the first connection mode is that port No. 1 of the ten-way switching valve is connected to port No. 10, port No. 2 is connected to port No. 3, port No. 4 is connected to port No. 5, port No. 6 is connected to port No. 7, and port No. 8 is connected to port No. 9; the first connection state is that port No. 1 of the six-way switching valve is connected to port No. 6, port No. 2 is connected to port No. 3, and port No. 4 is connected to port No. 5; A gas sample is introduced from port No. 1 of the first ten-way switching valve, so that the first quantitative loop, the second quantitative loop and the third quantitative loop are all filled with an equal amount of the gas sample; the gas sample is an octafluoropropane gas sample containing impurity components; Hydrogen, oxygen, argon, nitrogen, methane, and carbon monoxide component detection stage: Switch the interface state of the first ten-way switching valve to a second connection mode; the second connection mode is that port 1 of the ten-way switching valve is connected to port 2, port 3 is connected to port 4, port 5 is connected to port 6, port 7 is connected to port 8, and port 9 is connected to port 10; The first carrier gas is introduced from port 4 of the first ten-way switching valve. The first carrier gas carries the gas sample in the first quantitative loop into the first gas separation device, and after being separated into hydrogen, oxygen, argon, nitrogen, methane and carbon monoxide impurity components by the first gas separation device, enters the pulse discharge helium ionizer. The ionization detector is used for content detection; Carbon dioxide composition detection stage: Switching the interface state of the twentieth-way switching valve to the second connection mode; A second carrier gas is introduced from port No. 4 of the 20th-way switching valve, and the second carrier gas carries the gas sample in the second quantitative loop into the second gas separation device. After the combined peak of hydrogen, oxygen, argon, nitrogen, methane and carbon monoxide separated first by the second gas separation device is emptied, the interface state of the 20th-way switching valve is switched to the first connection mode; The third carrier gas is introduced from port No. 7 of the 20th switching valve, and the third carrier gas carries the carbon dioxide impurity component separated by the second gas separation device into the pulse discharge helium ionization detector for content detection; Fluorocarbon component detection stage: Switch the interface state of the six-way switching valve to a second connection state; the second connection state is that port 1 of the six-way switching valve is connected to port 2, port 3 is connected to port 4, and port 5 is connected to port 6; A fourth carrier gas is introduced from port No. 5 of the six-way switching valve, and the fourth carrier gas carries the gas sample in the third quantitative loop into the third gas separation device, and after the non-fluorocarbon components first separated by the third gas separation device are emptied, the interface state of the six-way switching valve is switched to the first connection state; The fourth carrier gas carries the fluorocarbon components separated by the third gas separation device into a pulse discharge helium ionization detector for content detection; the fluorocarbon components include carbon tetrafluoride, hexafluoroethane, hexafluoropropylene, heptafluoropropane and octafluorocyclobutane.

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