CN114733380B - Standard gas generating device - Google Patents
Standard gas generating device Download PDFInfo
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- CN114733380B CN114733380B CN202210209103.3A CN202210209103A CN114733380B CN 114733380 B CN114733380 B CN 114733380B CN 202210209103 A CN202210209103 A CN 202210209103A CN 114733380 B CN114733380 B CN 114733380B
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- dilution
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- 239000012895 dilution Substances 0.000 claims abstract description 37
- 238000010790 dilution Methods 0.000 claims abstract description 37
- 238000010438 heat treatment Methods 0.000 claims abstract description 25
- 238000002347 injection Methods 0.000 claims abstract description 17
- 239000007924 injection Substances 0.000 claims abstract description 17
- 239000007788 liquid Substances 0.000 claims abstract description 17
- 239000000203 mixture Substances 0.000 claims abstract description 5
- 239000007789 gas Substances 0.000 claims description 128
- 239000012086 standard solution Substances 0.000 claims description 15
- 239000000243 solution Substances 0.000 claims description 12
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 8
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 6
- 239000002904 solvent Substances 0.000 claims description 6
- 238000001514 detection method Methods 0.000 claims description 5
- 229910052757 nitrogen Inorganic materials 0.000 claims description 4
- 229910052786 argon Inorganic materials 0.000 claims description 3
- 239000004744 fabric Substances 0.000 claims description 3
- 239000011259 mixed solution Substances 0.000 claims description 3
- URLKBWYHVLBVBO-UHFFFAOYSA-N Para-Xylene Chemical group CC1=CC=C(C)C=C1 URLKBWYHVLBVBO-UHFFFAOYSA-N 0.000 description 20
- 238000000034 method Methods 0.000 description 8
- VZGDMQKNWNREIO-UHFFFAOYSA-N tetrachloromethane Chemical compound ClC(Cl)(Cl)Cl VZGDMQKNWNREIO-UHFFFAOYSA-N 0.000 description 8
- 239000003085 diluting agent Substances 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 238000002309 gasification Methods 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 3
- 230000007547 defect Effects 0.000 description 2
- 239000001307 helium Substances 0.000 description 2
- 229910052734 helium Inorganic materials 0.000 description 2
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 2
- 239000011261 inert gas Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000012452 mother liquor Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 238000003113 dilution method Methods 0.000 description 1
- 230000014509 gene expression Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000010413 mother solution Substances 0.000 description 1
- 239000012466 permeate Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000001269 time-of-flight mass spectrometry Methods 0.000 description 1
- 238000001196 time-of-flight mass spectrum Methods 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
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- Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
- Sampling And Sample Adjustment (AREA)
Abstract
The invention discloses a standard gas generating device which comprises a dilution gas source, a mass flow controller, a dilution gas preheating pipeline, a sample standard liquid injection pump, an injector, a gas mixing cavity, a cavity heating module and a gas detector. The flow rate, namely the dilution factor, of the dilution gas source is controlled by a mass flow controller, and the dilution gas source is mixed with the sample standard liquid injected by the injector after passing through a preheating pipeline and is fully mixed in a heated gas mixing cavity, so that standard gas with certain concentration is obtained. The device provided by the invention can prepare single-component or multi-component standard gas with certain concentration, fully utilizes a limited space to uniformly mix the gas, and has important significance for preparing the standard gas with high uniformity, stable performance and accurate concentration.
Description
Technical Field
The invention belongs to the technical field of gas preparation, and particularly relates to a standard gas generating device.
Background
The standard gas belongs to standard substances, is a measurement standard with high uniformity, stable performance and accurate magnitude, is used for calibrating measuring instruments and measuring processes in the fields of physics, chemistry, biology, engineering and the like, and has important significance in evaluating the detection capability and the accuracy of a measuring method of a detection laboratory. Common standard gas preparation techniques are generally permeation and liquid sample vaporization dilution. The standard gas generating device based on the permeation tube has the defects that one permeation tube can only correspond to one substance and can not prepare mixed standard gas; custom permeate tubes are required for unusual materials and are expensive. In addition, the permeation tube is incapable of a substance that is solid at room temperature. The liquid sample gasification dilution method is focused on a gas mixing cavity, such as a baffle plate, and the diluted gas and the sample gas are mixed through the baffle plate to obtain standard gas with a certain concentration. However, the baffles and the cavities have angular edges, thereby creating dead volumes that render the gas concentration inaccurate. In addition, the existing liquid sample gasification device has a defect of insufficient gas mixing volume in a certain space, so that standard gas is not uniform enough.
Disclosure of Invention
The invention provides a standard gas generating device, which aims to solve the problems that the conventional permeation tube-based device cannot prepare mixed standard gas and the gas prepared by a liquid sample gasification device is inaccurate and uneven.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
a standard gas generating device is sequentially connected with a dilution gas source, a mass flow controller, a gas mixing cavity and a gas detector from left to right through pipelines; the connecting pipeline between the mass flow controller and the gas mixing cavity is a dilution gas preheating pipeline;
the device also comprises a syringe and a sample standard solution injection pump; the injector and the sample standard solution injection pump are positioned below the gas mixing cavity, and the injector is arranged on the sample standard solution injection pump;
the bottom of the gas mixing cavity is also provided with a cavity heating module for heating the gas mixing cavity; the gas mixing cavity is a cylinder, and a cylindrical cavity a, a cylindrical cavity b, a cylindrical cavity c and a cylindrical cavity d are arranged between the upper bottom surface and the lower bottom surface in the gas mixing cavity and are used for increasing the gas mixing volume so that the gas is fully mixed without dead volume; a pipeline is connected between the tops of the cylindrical cavity a and the cylindrical cavity b, and between the bottoms of the cylindrical cavity c and the cylindrical cavity c; the air inlet of the cylindrical cavity a is connected with the air outlet of the dilution gas preheating pipeline, and the air outlet of the cylindrical cavity d is connected with the sample inlet of the gas detector; the bottom air inlet of the cylindrical cavity a and the bottom air outlet of the cylindrical cavity d are respectively communicated with the cavity heating module;
the outer wall of the dilution gas preheating pipeline is covered with a heating belt or a heating cloth so as to preheat gas;
the flow rate, namely the dilution multiple, of the dilution gas source is controlled by a mass flow controller, the dilution gas source is mixed with the sample standard liquid injected by the injector after passing through a dilution gas preheating pipeline, and the mixture is fully mixed in a heated gas mixing cavity, and the obtained standard gas enters a gas detector for detection.
In the above technical solution, further, the source of the dilution gas is generally inert gas nitrogen, argon or helium.
In the above technical scheme, further, the pump speed of the sample standard liquid injection pump can be adjusted, and the concentration of the required standard gas is controlled by controlling the sample standard liquid amount entering the gas mixing cavity in unit time.
In the above technical solution, further, the inside of the syringe may be filled with a pure solvent or a single solution or a mixed solution, which may be one component or multiple components.
In the above technical solution, further, the gas detector may be a mass spectrometer or a gas chromatograph.
In the above technical scheme, further, the flow rate of the sample standard solution injection pump is 0-200mL/min, and the flow rate controlled by the mass flow controller is 0-30L/min.
In the above technical scheme, further, the heating temperature of the cavity heating module is room temperature-500 ℃, and the preheating temperature of the dilution gas preheating pipeline is room temperature-500 ℃.
Preferably, the inside of the cylindrical cavity is not provided with edges, and the cylindrical cavity a, the cylindrical cavity b, the cylindrical cavity c and the cylindrical cavity d are uniformly distributed.
Compared with the prior art, the invention has the beneficial effects that:
the device provided by the invention can prepare single-component or multi-component standard gas with certain concentration, fully utilizes a limited space to uniformly mix the gas, and has important significance for preparing the standard gas with high uniformity, stable performance and accurate concentration.
Drawings
Fig. 1 is a standard gas generator of the present invention.
In the figure, 1. A dilution gas source; 2. a mass flow controller; 3. a dilution gas preheating pipeline; 4. a sample standard solution injection pump; 5. a syringe; 6. a gas mixing chamber; 7. a cavity heating module; 8. a gas detector.
In the figure, 6-1. Cylindrical cavity a;6-2. A cylindrical cavity b;6-3 a cylindrical cavity c;6-4 cylindrical cavity d.
Detailed Description
The treatment process according to the invention is further described below with reference to specific examples.
It should be noted that, without conflict, the embodiments of the present invention and features of the embodiments may be combined with each other. The invention will be described in detail below with reference to the drawings in connection with embodiments.
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present invention. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.
The relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated otherwise. Meanwhile, it should be clear that the dimensions of the respective parts shown in the drawings are not drawn in actual scale for convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.
In the description of the present invention, it should be understood that the azimuth or positional relationships indicated by the azimuth terms such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal", and "top, bottom", etc., are generally based on the azimuth or positional relationships shown in the drawings, merely to facilitate description of the present invention and simplify the description, and these azimuth terms do not indicate and imply that the apparatus or elements referred to must have a specific azimuth or be constructed and operated in a specific azimuth, and thus should not be construed as limiting the scope of protection of the present invention: the orientation word "inner and outer" refers to inner and outer relative to the contour of the respective component itself.
Example 1
As shown in fig. 1, a standard gas generating device is connected with a dilution gas source 1, a mass flow controller 2, a gas mixing cavity 6 and a gas detector 8 in sequence from left to right through pipelines. The device also comprises a syringe 5 and a sample standard solution injection pump 4; the connecting pipeline between the mass flow controller 2 and the gas mixing cavity 6 is a dilution gas preheating pipeline 3; the injector 5 and the sample standard solution injection pump 4 are positioned below the gas mixing cavity 6, and the injector 5 is arranged on the standard solution injection pump 4;
the bottom of the gas mixing cavity 6 is also provided with a cavity heating module 7 for heating the gas mixing cavity 6, and the heating temperature of the cavity heating module 7 is between room temperature and 500 ℃; the gas mixing cavity 6 is a cylinder, and a cylindrical cavity a 6-1, a cylindrical cavity b 6-2, a cylindrical cavity c 6-3 and a cylindrical cavity d 6-4 which are uniformly distributed are arranged between the upper bottom surface and the lower bottom surface in the gas mixing cavity 6 and are used for increasing the gas mixing volume so that the gas is fully mixed and the dead volume is avoided;
a pipeline is connected between the tops of the cylindrical cavity a and the cylindrical cavity b, and between the bottoms of the cylindrical cavity c and the cylindrical cavity c; the air inlet of the cylindrical cavity a is connected with the air outlet of the dilution gas preheating pipeline 3, and the air outlet of the cylindrical cavity d is connected with the sample inlet of the gas detector 8; the bottom air inlet of the cylindrical cavity a and the bottom air outlet of the cylindrical cavity d are respectively communicated with the cavity heating module 7.
The outer wall of the dilution gas preheating pipeline 3 is covered with a heating belt or a heating cloth, so that the preheating of gas can be realized. The diluent gas source 1 is generally inert gas nitrogen, argon or helium, the flow rate, namely the dilution factor, of the diluent gas source 1 is controlled by the mass flow controller 2, the diluent gas source 1 is mixed with the sample standard liquid injected by the injector 5 after passing through the diluent gas preheating pipeline 3, and the mixture is fully mixed in the heated gas mixing cavity 6, and the obtained standard gas enters the gas detector 8 for detection.
The pump speed of the sample standard solution injection pump 4 can be adjusted, and the concentration of the required standard gas is controlled by controlling the sample standard solution amount entering the gas mixing cavity 6 in unit time, wherein the flow rate of the sample standard solution injection pump 4 is 0-200mL/min, and the pure solvent or the single solution or the mixed solution can be one component or multiple components.
The gas detector 8 may be a mass spectrometer or a gas chromatograph. The flow rate controlled by the mass flow controller 2 is 0-30L/min, and the preheating temperature of the dilution gas preheating pipeline 3 is room temperature-500 ℃.
Further, as one example, the dilution gas source 1 is nitrogen, and the mass flow controller 2 sets the flow rate to 2L/min.
Further, as one example, the pump speed of the sample standard solution syringe pump 4 is 20. Mu.L/min.
Further, as one example, the injector 5 is filled with a carbon tetrachloride solution of paraxylene.
Further, as one of the embodiments, the heating temperature of the cavity heating module 7 is set to 160 ℃.
Further, as one of the embodiments, the gas detector 8 is a mass spectrometer.
The invention prepares 100ppbv of p-xylene standard gas, which comprises the following specific steps: 0.3734g of pure paraxylene is weighed by an analytical balance and put in a beaker, and carbon tetrachloride solvent is dissolved and transferred to a volumetric flask a (mother liquor) with a volume of 25 mL; transferring the solution in the 500 mu L volumetric flask a by a liquid transfer gun, and fixing the volume of the carbon tetrachloride solvent to a 25mL volumetric flask b (50 times of mother solution dilution); the solution in 2500. Mu.L volumetric flask b was removed with a pipette and the carbon tetrachloride solvent was fixed to volume C (500-fold dilution of mother liquor) of 25mL volumetric flask. The liquid in the 1mL volumetric flask c was taken out by the syringe 5, and was fixed to the sample standard liquid syringe pump 4, and the pump speed was set at 20. Mu.L/min.
Note that: the molar mass of the paraxylene is 106.165g/mol; the boiling point of the paraxylene is 138.5 ℃ and 160 ℃ can ensure that the paraxylene is completely gasified; the molar volume of the gas at 160℃was 35.54L/mol.
The concentration of the paraxylene standard gas prepared by the method of the invention is:
detecting by photoionization time-of-flight mass spectrometry, wherein the peak area is 24442;
100ppbv of p-xylene standard gas prepared by a gas library of Dalian chemical and physical institute of academy of sciences of China is detected by the same instrument parameter of the photoionization time-of-flight mass spectrum, and the peak area is 24280.
Compared with the paraxylene standard gas prepared by a gas library, the error of the paraxylene standard gas prepared by the method is as follows:
the error is only 0.67%, which indicates the accuracy of the standard gas preparation of the invention.
The technical principle of the present invention is described above in connection with the specific embodiments. The description is made for the purpose of illustrating the general principles of the invention and should not be taken in any way as limiting the scope of the invention. Other embodiments of the invention will occur to those skilled in the art from consideration of this specification without the exercise of inventive faculty, and such equivalent modifications and alternatives are intended to be included within the scope of the invention as defined in the claims.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.
Claims (7)
1. A standard gas generating device, characterized in that: the device is sequentially connected with a dilution gas source (1), a mass flow controller (2), a gas mixing cavity (6) and a gas detector (8) from left to right through pipelines; the connecting pipeline between the mass flow controller (2) and the gas mixing cavity (6) is a dilution gas preheating pipeline (3);
the device also comprises a syringe (5) and a sample standard solution injection pump (4); the injector (5) and the sample standard solution injection pump (4) are positioned below the gas mixing cavity, and the injector (5) is arranged on the sample standard solution injection pump (4);
the bottom of the gas mixing cavity is also provided with a cavity heating module for heating the gas mixing cavity; the gas mixing cavity is a cylinder, and a cylindrical cavity a (6-1), a cylindrical cavity b (6-2), a cylindrical cavity c (6-3) and a cylindrical cavity d (6-4) are arranged between the upper bottom surface and the lower bottom surface in the gas mixing cavity and are used for increasing the gas mixing volume so that the gas is fully mixed and the dead volume is avoided; the inside of the cylindrical cavity is free of edges and corners, and the cylindrical cavity a (6-1), the cylindrical cavity b (6-2), the cylindrical cavity c (6-3) and the cylindrical cavity d (6-4) are uniformly distributed; a pipeline is connected between the tops of the cylindrical cavity a and the cylindrical cavity b, between the cylindrical cavity c and the cylindrical cavity d, a pipeline is connected between the bottoms of the cylindrical cavity b and the cylindrical cavity c, and an air inlet of the cylindrical cavity a is connected with an air outlet of the dilution air preheating pipeline (3); the air outlet of the cylindrical cavity d is connected with the sample inlet of the gas detector (8); the bottom air inlet of the cylindrical cavity a and the bottom air outlet of the cylindrical cavity d are respectively communicated with the cavity heating module (7);
the outer wall of the dilution gas preheating pipeline is covered with a heating belt or a heating cloth so as to preheat gas;
the flow rate, namely the dilution multiple, of the dilution gas source (1) is controlled by the mass flow controller (2), the dilution gas source is mixed with the sample standard liquid injected by the injector (5) after passing through the dilution gas preheating pipeline (3), and the mixture is fully mixed in the heated gas mixing cavity (6), and the obtained standard gas enters the gas detector (8) for detection.
2. The standard gas generator according to claim 1, wherein: the dilution gas source (1) is one of nitrogen and argon.
3. The standard gas generator according to claim 1, wherein: the pump speed of the sample standard liquid injection pump (4) can be adjusted, and the concentration of the required standard gas is controlled by controlling the sample standard liquid amount entering the gas mixing cavity (6) in unit time.
4. The standard gas generator according to claim 1, wherein: the syringe (5) may be filled with pure solvent or a single solution or a mixed solution.
5. The standard gas generator according to claim 1, wherein: the gas detector (8) may be a mass spectrometer or a gas chromatograph.
6. The standard gas generator according to claim 1, wherein: the flow rate of the sample standard liquid injection pump (4) is 0-200mL/min, and the flow rate controlled by the mass flow controller (2) is 0-30L/min.
7. The standard gas generator according to claim 1, wherein: the heating temperature of the cavity heating module (7) is between room temperature and 500 ℃, and the preheating temperature of the dilution gas preheating pipeline (3) is between room temperature and 500 ℃.
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| CN202210209103.3A CN114733380B (en) | 2022-03-04 | 2022-03-04 | Standard gas generating device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210209103.3A CN114733380B (en) | 2022-03-04 | 2022-03-04 | Standard gas generating device |
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| CN114733380A CN114733380A (en) | 2022-07-12 |
| CN114733380B true CN114733380B (en) | 2024-02-23 |
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| CN101713712A (en) * | 2008-10-06 | 2010-05-26 | 中国科学院大连化学物理研究所 | Dynamic preparation device for standard gas of solid-phase or liquid-phase compounds and application thereof |
| KR20110070064A (en) * | 2009-12-18 | 2011-06-24 | 한국철도기술연구원 | Apparatus for mixing reference gases |
| CN103163007A (en) * | 2011-12-19 | 2013-06-19 | 中国科学院大连化学物理研究所 | Solid phase and liquid phase compound dynamic gas preparation device and gas preparation method |
| CN207636364U (en) * | 2017-11-02 | 2018-07-20 | 中国科学院大连化学物理研究所 | A kind of flue gas particles classification dilution sampling device |
| CN209333548U (en) * | 2018-12-10 | 2019-09-03 | 杭州旭昱科技有限公司 | A kind of liquid chromatogram geopressure gradient static mixer |
| CN111220445A (en) * | 2018-11-27 | 2020-06-02 | 中国科学院大连化学物理研究所 | Dynamic preparation device for gas sample |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01281137A (en) * | 1988-05-07 | 1989-11-13 | Koujiyundo Kagaku Kenkyusho:Kk | Method and apparatus for vaporizing liquid raw material |
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- 2022-03-04 CN CN202210209103.3A patent/CN114733380B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101713712A (en) * | 2008-10-06 | 2010-05-26 | 中国科学院大连化学物理研究所 | Dynamic preparation device for standard gas of solid-phase or liquid-phase compounds and application thereof |
| KR20110070064A (en) * | 2009-12-18 | 2011-06-24 | 한국철도기술연구원 | Apparatus for mixing reference gases |
| CN103163007A (en) * | 2011-12-19 | 2013-06-19 | 中国科学院大连化学物理研究所 | Solid phase and liquid phase compound dynamic gas preparation device and gas preparation method |
| CN207636364U (en) * | 2017-11-02 | 2018-07-20 | 中国科学院大连化学物理研究所 | A kind of flue gas particles classification dilution sampling device |
| CN111220445A (en) * | 2018-11-27 | 2020-06-02 | 中国科学院大连化学物理研究所 | Dynamic preparation device for gas sample |
| CN209333548U (en) * | 2018-12-10 | 2019-09-03 | 杭州旭昱科技有限公司 | A kind of liquid chromatogram geopressure gradient static mixer |
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