Gas chromatographic column, gas chromatograph and analysis method

Abstract

The embodiment of the invention discloses a gas chromatographic column, a gas chromatograph and an analysis method, and belongs to the technical field of gas chromatographs.The gas chromatographic column is provided with a support and a capillary tube, the capillary tube is spirally laid on the supporting face of the support, and the capillary tube comprises a stationary phase layer and a metal layer; the sample inlet end and the sample outlet end of the capillary tube are respectively connected with the heating piece, the spiral structural design of the capillary tube can effectively reduce the occupied space of the capillary tube and increase the contact area and contact time of the stationary phase layer and a to-be-detected substance introduced into the capillary tube, and the outer wall of the capillary tube is a metal layer, so that the overall resistance of the capillary tube can be effectively reduced; according to the present invention, the temperature rising rate of the capillary tube is effectively increased, the capillary tube is heated to the target temperature within 5-15 s, and during the temperature rising process, the stationary phase layer can separate the various components in the to-be-detected substance so as to effectively improve the analysis efficiency of the to-be-detected substance, effectively shorten the analysis time consumption, reduce the power consumption and reduce the analysis cost.

Description

Technical Field

[0001] The present application relates to the technical field of gas chromatographs, and in particular to a gas chromatograph column, a gas chromatograph and an analysis method. Background Art

[0002] The column oven heating technology of traditional gas chromatographs generates heat by electric heating wires, and forces air convection through fans, placing the chromatographic column in the air convection to achieve uniform heating. However, the linear heating rate of the gas chromatographic column in traditional gas chromatographs is slow, only reaching about 60℃ / min, and the analysis time is generally more than 30min, which is time-consuming. In addition, the heating power consumption of the column oven is as high as 1kW to 2kW, which is high. Summary of the invention

[0003] The embodiments of the present application provide a gas chromatography column, a gas chromatograph and an analysis method, which can solve the problems of slow heating rate of the gas chromatography column, long analysis time and high power consumption in the existing gas chromatograph.

[0004] A first aspect of an embodiment of the present application provides a gas chromatography column, comprising: a support having a supporting surface; a capillary, one end of the capillary being an injection end and the other end being an outlet end, a substance to be tested can enter the capillary through the injection end, the substance to be tested includes multiple components, the capillary is spirally laid on the supporting surface, and along the radial direction of the capillary, the capillary includes a stationary phase layer and a metal layer arranged from the inside to the outside; a heating element is arranged on one side of the support, the injection end and the outlet end are respectively connected to the heating element; the heating element can electrically heat the capillary so that the capillary is heated to a target temperature within 5s to 15s, and during the heating process, the stationary phase layer can separate the multiple components in the substance to be tested, and the separated components can be discharged from the capillary through the outlet end.

[0005] Optionally, the inner wall surface of the metal layer is inertized to form an inert layer, and the stationary phase layer is arranged on the inert layer; the substance to be tested includes volatile organic matter, and the stationary phase layer includes one of a polar stationary phase and a non-polar stationary phase, the polar stationary phase includes polymethylsiloxane containing 50wt% phenyl, and the non-polar stationary phase includes polymethylsiloxane containing 5wt% phenyl; the heating rate of the capillary is 15℃ / s~25℃ / s.

[0006] Optionally, the length of the capillary is 0.8m to 1.2m, and the inner diameter of the capillary is 0.2mm to 0.3mm; the substance to be tested entering the capillary through the injection end can be discharged from the capillary through the output end within 15s to 25s.

[0007] Optionally, the gas chromatography column also includes two insulating films, the two insulating films are arranged at intervals, the capillary is arranged between the two insulating films, and the two insulating films cooperate to form a clamp for the capillary; the heat resistance temperature of the insulating film is higher than the target temperature; the injection end and the sample outlet end extend to the outside of the two insulating films respectively; the heating element includes a first heating element and a second heating element, the injection end is connected to the first heating element, and the sample outlet end is connected to the second heating element.

[0008] Optionally, the gas chromatography column also includes a temperature measuring component and an air cooling component; the temperature measuring component is connected to the capillary to measure the temperature of the capillary; the air cooling component is mounted on the support, with the air outlet end of the air cooling component facing the capillary, and the air cooling component can cool the temperature of the capillary from the target temperature to the initial temperature; the cooling rate of the capillary is 30°C / s to 50°C / s.

[0009] A second aspect of an embodiment of the present application provides a gas chromatograph, the gas chromatograph comprising: a gas chromatograph column as described above; an injection port capable of introducing a substance to be tested; a valve body, the injection port being connected to the valve body, and the injection end of a capillary in the gas chromatograph column being connected to the valve body; a pretreatment component, the pretreatment component comprising an inlet end and an outlet end, the inlet end and the outlet end being respectively connected to the valve body; a carrier gas source being connected to the valve body; a detection component, the sample outlet end of the capillary being connected to the detection component; the injection port being capable of being connected to the pretreatment component through the valve body to form a sampling passage; the carrier gas source being capable of being connected to the inlet end through the valve body, and the outlet end being capable of being connected to the injection end of the capillary through the valve body to form an injection passage; the valve body being capable of being connected to the sampling passage and the The valve body is switched to the sampling passage, and the substance to be tested introduced into the injection port can be transported to the pretreatment component through the sampling passage, and the pretreatment component can enrich the substance to be tested; the valve body is switched to the injection passage, and the carrier gas in the carrier gas source can pass the substance to be tested enriched in the pretreatment component into the capillary through the injection passage; the heating element in the gas chromatography column can electrically heat the capillary, so that the capillary is heated to the target temperature within 5s to 15s, and during the heating process, the stationary phase layer in the capillary can separate multiple components in the substance to be tested introduced into the capillary, and the separated components can be discharged to the detection component through the sample outlet, and the detection component can analyze and detect the components to generate a chromatogram.

[0010] Optionally, the gas chromatograph also includes a pump body, the air extraction end of the pump body is connected to the valve body, and the pump body can be connected to the sampling passage through the valve body to transport the substance to be tested to the pretreatment part through the inlet and the valve body; the pump body can also discharge impurity gases mixed in the substance to be tested.

[0011] Optionally, the valve body comprises a six-way valve.

[0012] Optionally, the gas chromatograph further comprises a heating component, the inlet end and the outlet end are respectively connected to the heating component, the heating component can electrically heat the pretreatment component, and the pretreatment component can be heated to a target temperature within 1s to 3s.

[0013] A third aspect of the embodiments of the present application provides an analysis method of the gas chromatograph as described above, the analysis method comprising the following steps:

[0014] Switch the valve body to the sampling passage;

[0015] Passing the substance to be tested into the pretreatment component through the sample inlet and the valve body;

[0016] Switching the valve body from the sampling passage to the injection passage;

[0017] Passing the carrier gas in the carrier gas source into the pretreatment component through the valve body, and passing the substance to be tested in the pretreatment component into the capillary through the valve body by the carrier gas;

[0018] The capillary is electrically heated by a heating element so that the capillary is heated to a target temperature within 5s to 15s. During the heating process, the capillary separates multiple components in the substance to be tested and discharges the separated components to the detection element through the sample outlet end;

[0019] The components are analyzed and detected by the detection element to generate a chromatogram.

[0020] Optionally, the step of passing the substance to be tested into the pretreatment component through the sample inlet via the valve body further includes:

[0021] The substance to be tested is transported to the pre-treatment element through the valve body by the pump body;

[0022] The step of passing the substance to be tested through the sample inlet and the valve body into the pretreatment component is completed within 8s to 12s;

[0023] The step of switching the valve body from the sampling passage to the injection passage also includes:

[0024] The pretreatment component is heated by a temperature-increasing component so that the pretreatment component is heated to a target temperature within 1 second to 3 seconds.

[0025] Optionally, in the step of passing the substance to be tested in the pre-treatment component into the capillary via the valve body by means of a carrier gas, the flow rate of the carrier gas is 3 mL / min to 5 mL / min;

[0026] In the step of electrically heating the capillary tube by a heating element, the heating rate of the capillary tube is 15°C / s to 25°C / s;

[0027] In the step of discharging the separated components to the detection element through the sample outlet, the substance to be detected that enters the capillary through the sample injection end can be discharged from the capillary through the sample outlet within 15s to 25s.

[0028] The beneficial effects of the present application are to provide a gas chromatography column, a gas chromatograph having the gas chromatography column, and an analysis method for the gas chromatography column. The gas chromatography column is provided with a support and a capillary, one end of the capillary is an injection end, and the other end is an output end, and the capillary is spirally laid on the supporting surface of the support, and the capillary comprises a stationary phase layer and a metal layer arranged from the inside to the outside along the radial direction, and a heating element is provided, and the injection end and the output end of the capillary are respectively connected to the heating element, and the spiral structural design of the capillary can effectively reduce the occupied space of the capillary, and the spiral structural design can increase the contact area and contact time between the stationary phase layer and the substance to be tested introduced into the capillary, so that the stationary phase layer can be fully contacted with the substance to be tested by using a capillary of a shorter length, thereby ensuring the separation effect of the stationary phase layer on multiple components in the substance to be tested, and the outer wall of the capillary is provided with a metal layer, which can effectively reduce the capillary. The overall resistance of the capillary is high, and the current passing through the capillary is relatively large during the process of electrically heating the capillary by the heating element, thereby effectively improving the heating rate of the capillary, so that the capillary is heated to the target temperature within 5s to 15s. During the heating process, the stationary phase layer can separate multiple components in the substance to be tested, and the separated components can be discharged from the capillary through the sample outlet end of the capillary, thereby effectively improving the analysis efficiency of the substance to be tested, and the length of the capillary is relatively short, so that the flow rate of the substance to be tested passing into the capillary per unit time is large, the substance to be tested can pass through the capillary in a short time and realize the separation of multiple components, effectively shortening the analysis time, reducing power consumption, and reducing the analysis cost. The gas chromatography column is suitable for a portable gas chromatograph, meeting the use requirements of the portable gas chromatograph for fast heating, fast separation speed, small size, low power consumption, and low cost, and the gas chromatography column is suitable for the detection of components in volatile organic compounds. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 is a schematic diagram of the structure of a gas chromatography column provided in an embodiment of the present application;

[0031] Figure 2 It is a schematic diagram of the structure of the gas chromatography column provided in an embodiment of the present application after the insulating film is removed;

[0032] Figure 3 It is a schematic diagram of the combined structure of a capillary tube and a heating element in a gas chromatography column provided in an embodiment of the present application;

[0033] Figure 4 It is a schematic diagram of the combined structure of a capillary and an insulating film in a gas chromatography column provided in an embodiment of the present application;

[0034] Figure 5 yes Figure 4 Exploded diagram of

[0035] Figure 6 Schematic diagram of the structure of a capillary in a gas chromatography column provided in an embodiment of the present application;

[0036] Figure 7 is a schematic diagram of the cross-sectional structure of a capillary in a gas chromatography column provided in an embodiment of the present application;

[0037] Figure 8 is a schematic diagram of the structure of a gas chromatograph provided in an embodiment of the present application;

[0038] Fig. 9 This is the intention of the connection relationship between the various components when the gas chromatograph provided in the embodiment of the present application is in the sampling path;

[0039] Fig.10 This is the intention of the connection relationship between the various components when the gas chromatograph provided in the embodiment of the present application is in the injection path;

[0040] Fig.11 The chromatogram is generated by analyzing and testing a standard solution of C6-C14 normal alkanes using the gas chromatograph provided in the embodiment of the present application.

[0041] Description of reference numerals:

[0042] 100. Gas chromatography column;

[0043] 10. support, 101. first support plate, 102. second support plate, 11. support surface;

[0044] 20. capillary, 201. stationary phase layer, 202. metal layer, 203. inert layer, 21. injection end, 22. sample outlet end, 23. casing;

[0045] 30. Heating element, 31. First heating element, 32. Second heating element;

[0046] 40. Insulating film;

[0047] 50. Temperature measuring parts;

[0048] 60. Air cooling parts;

[0049] 70, first connecting pipe, 71, second connecting pipe;

[0050] 200. Gas chromatograph;

[0051] 210, injection port;

[0052] 220, valve body, 221, first interface, 222, second interface, 223, third interface, 224, fourth interface, 225, fifth interface, 226, sixth interface;

[0053] 230, pretreatment unit, 231, inlet end, 232, outlet end, 233, trap, 234, analytical unit;

[0054] 240, carrier gas source;

[0055] 250. Inspection parts;

[0056] 260, pump body;

[0057] 270, a temperature raising component, 271, a first temperature raising component, 272, a second temperature raising component;

[0058] X, first direction, Y, second direction, Z, third direction. DETAILED DESCRIPTION

[0059] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present application, and are not used to limit the present application. In the present application, unless otherwise stated, the directional words used, such as "upper" and "lower", generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; and "inside" and "outside" refer to the outline of the device.

[0060] In some embodiments of the present application, a gas chromatography column 100 is provided, referring to Figure 1 to Figure 7 The gas chromatography column 100 includes: a support 10 , a capillary 20 and a heating element 30 .

[0061] Reference Figure 1 and Figure 2 The support 10 has a support surface 11. Specifically, the support 10 has a first direction X, a second direction Y and a third direction Z that intersect each other. Figure 1-2 In the illustrated embodiment, the first direction X, the second direction Y and the third direction Z are orthogonal to each other, the first direction X is parallel to the length direction of the support 10, the second direction Y is parallel to the width direction of the support 10, and the third direction Z is parallel to the height direction of the support 10. The support 10 includes a first support plate 101 and a second support plate 102 spaced apart along the third direction Z, and the support surface 11 is a side of the first support plate 101 facing the second support plate 102.

[0062] Reference Figure 2 to Figure 6 One end of the capillary 20 is a sample injection end 21, and the other end is a sample outlet end 22. The substance to be tested can enter the capillary 20 through the sample injection end 21. The substance to be tested includes multiple components. Figure 2 The capillary 20 is laid in a spiral shape on the support surface 11 of the support 10. Specifically, the capillary 20 is laid in a spiral shape on one side of the first support plate 101 along the third direction Z toward the second support plate 102. Figure 7 Along the radial direction of the capillary 20 , the capillary 20 includes a stationary phase layer 201 and a metal layer 202 arranged from the inside to the outside.

[0063] Among them, refer to Figure 2-3 as well as Figure 5-6 The capillary 20 is in a spiral shape, which means that the capillary 20 takes the sample outlet end 22 as the starting point and forms a spiral shape around the sample outlet end 22 from the inside to the outside, and the formed spiral capillary 20 can be laid on the support surface 11. Specifically, the spiral capillary 20 is laid flat on the support surface 11, rather than being arranged on the support surface 11 in a spiral ascending manner.

[0064] Reference Figure 1 to Figure 3The injection end 21 and the sample outlet end 22 of the capillary 20 are respectively connected to the heating element 30, and the heating element 30 is arranged on one side of the support 10. Specifically, the heating element 30 is arranged on one side of the support 10 along the first direction X. The heating element 30 includes a first heating element 31 and a second heating element 32. The first heating element 31 and the second heating element 32 are arranged at intervals along the second direction Y of the support 10. The injection end 21 is connected to the first heating element 31, and the sample outlet end 22 is connected to the second heating element 32. The heating element 30 can electrically heat the capillary 20, so that the capillary 20 is heated to the target temperature within 5s to 15s. During the heating process, the stationary phase layer 201 can separate multiple components in the substance to be tested that is passed into the capillary 20, and the separated components can be discharged from the capillary 20 through the sample outlet end 22. Specifically, the first heating element 31 , the second heating element 32 and the capillary 20 can form a loop, and the first heating element 31 and the second heating element 32 are respectively electrically connected to a power source as electrodes, thereby achieving electrical heating of the capillary 20 .

[0065] Traditional gas chromatographs are large in size, and the internal column oven heating technology generates heat by heating wires, and forces air convection through fans, placing the chromatographic column in air convection to achieve uniform heating. However, the linear heating rate of the gas chromatograph column in traditional gas chromatographs is slow, only reaching about 60°C / min. The analysis time is generally more than 30 minutes, which is time-consuming. In addition, the heating power consumption of the column oven is as high as 1 kW to 2 kW, which is high. For relatively small portable gas chromatographs, the power of the whole machine usually does not exceed 500 watts. Portable gas chromatographs usually need to obtain analysis results in 5 minutes to 10 minutes. The heating rate of 60°C / min of the gas chromatograph column in traditional gas chromatographs is obviously not suitable for the technical requirements of portable gas chromatographs.

[0066] In addition, the heating technology of the gas chromatography column in the existing portable gas chromatograph is more commonly used direct resistance heating technology, which is used to achieve rapid programmed temperature rise of the gas chromatography column. Direct resistance heating technology usually uses electric heating wires in parallel with the chromatography column, electric heating sleeves outside the chromatography column to directly heat the gas chromatography column, and metal film coated on the outer wall of the quartz capillary as a heating resistor to increase the heating rate of the gas chromatography column. However, the existing gas chromatography column has problems such as complex manufacturing process, uneven coating of metal thin layer, uneven local heating of the gas chromatography column, and low strength of the glass capillary column, which can easily cause local overheating of the gas chromatography column, causing the metal thin layer on the outer wall of the quartz capillary to fall off, the loss of the stationary phase and the damage of the chromatography column, affecting the analysis efficiency.

[0067] The gas chromatography column 100 provided in the embodiment of the present application is provided with a support 10, and the capillary 20 is provided on the support surface 11 of the support 10. Specifically, the capillary 20 is laid on the support surface 11 of the support 10 in a spiral shape, and the capillary 20 includes a stationary phase layer 201 and a metal layer 202 arranged from the inside to the outside in a radial direction, and a heating element 30 is provided, and the injection end 21 and the sample outlet end 22 of the capillary 20 are respectively connected to the heating element 30. The capillary 20 has a spiral structural design, and the capillary 20 is laid on the support surface 11 in a spiral shape, so that the capillary 20 The capillary 20 only occupies the space within the two-dimensional plane defined by the first direction X and the second direction Y, thereby effectively reducing the space occupied by the capillary 20 in the third direction Z, so that the gas chromatography column 100 can be suitable for a relatively small portable gas chromatograph. Moreover, the spiral structure design of the capillary 20 can increase the contact area and contact time between the stationary phase layer 201 and the substance to be tested introduced into the capillary 20, so that the stationary phase layer 201 can be fully contacted with the substance to be tested by using a capillary of a shorter length, thereby ensuring the separation effect of the stationary phase layer 201 on multiple components in the substance to be tested;

[0068] In addition, the outer layer of the capillary 20 is a metal layer 202, so that the capillary 20 forms a metal capillary. The resistance of the metal layer 202 is relatively small. When the heating element 30 electrically heats the capillary 20, the current passing through the capillary 20 is relatively large, thereby effectively improving the heating rate of the capillary, so that the capillary is heated to the target temperature within 5s to 15s. During the heating process, the stationary phase layer can separate multiple components in the substance to be tested, and the separated components can be discharged from the capillary through the sample outlet end of the capillary, thereby effectively improving the analysis efficiency of the substance to be tested and meeting the use requirements of a portable gas chromatograph. Moreover, compared with a quartz capillary coated with a thin metal film, it can effectively avoid the occurrence of metal layer shedding, thereby ensuring the use stability of the gas chromatography column 100.

[0069] In addition, the spiral structural design of the capillary 20 allows the capillary 20 to be of a shorter length, thereby making the flow rate of the substance to be tested passing through the capillary 20 per unit time larger. The substance to be tested can pass through the capillary 20 in a short time and realize the separation of multiple components in the substance to be tested, effectively shortening the analysis time, reducing power consumption, and reducing analysis costs. The gas chromatography column 100 is suitable for a portable gas chromatograph, meeting the use requirements of a portable gas chromatograph for fast heating, fast separation speed, small size, low power consumption, and low cost, and the gas chromatography column is suitable for the detection of components in volatile organic compounds.

[0070] In some embodiments, reference Figure 7The capillary 20 also includes an inert layer 203. The inner wall surface of the metal layer 202 is inerted to form the inert layer 203. The stationary phase layer 201 is arranged on the inert layer 203. Specifically, the stationary phase layer 201 is coated on the inert layer 203. The design of the inert layer 203 and the inert layer 203 is formed by the metal layer 202 through inerting treatment. The inert layer 203, as a part of the metal layer 202, can effectively ensure the stability between the stationary phase layer 201 and the metal layer 202, thereby ensuring the use stability of the stationary phase layer 201, thereby ensuring the separation effect of the stationary phase layer 201 on multiple components in the substance to be tested passed into the capillary 20.

[0071] In some embodiments, the metal layer 202 is made of stainless steel.

[0072] In some embodiments, the stationary phase layer 201 includes one of a polar stationary phase and a non-polar stationary phase, and the non-polar stationary phase includes polymethylsiloxane containing 5 wt % of phenyl groups.

[0073] In some embodiments, the substances to be tested include volatile organic compounds (VOCs, Volatile Organic Compounds), which refer to common VOCs compounds with a saturated vapor pressure greater than 70.91 Pa at room temperature, a boiling point below 50°C to 260°C at a standard atmospheric pressure of 101.3 kPa, and an initial distillation point equal to 250 degrees Celsius.

[0074] In some embodiments, the substance to be tested is a volatile organic compound with a boiling point of 50°C to 200°C. For example, volatile organic compounds include benzene, toluene, xylene, styrene, trichloroethylene, chloroform, trichloroethane, diisocyanate (TDI), diisocyanatolyl ester, etc. Specifically, the boiling point of benzene is 80.1°C, the boiling point of toluene is 110.6°C, the boiling point of o-xylene is 144.4°C, the boiling point of styrene is 145°C, the boiling point of trichloroethylene is 87°C, the boiling point of chloroform is 61.2°C, and the boiling point of 1,1,2-trichloroethane is 110°C to 1 15℃, the boiling point of triisocyanate (TDI) is 115℃~120℃, and the boiling point of 2,5-toluene diisocyanate is 138℃-139℃. These substances are widely present in industrial emissions, automobile exhaust, interior decoration materials, and various solvents, detergents, coatings and cosmetics used in daily life. They are not only harmful to the environment, but also to human health. Therefore, it is necessary to use a portable gas chromatograph to timely, quickly and accurately analyze the composition of the test substance.

[0075] When the substance to be tested is a volatile organic compound, the various components in the substance to be tested are mostly non-polar compounds, and the stationary phase in the stationary phase layer 201 is a non-polar stationary phase. Specifically, the non-polar stationary phase is polymethylsiloxane containing 5wt% phenyl. The non-polar stationary phase has a good separation effect on low-boiling point, volatile, weakly polar and non-polar substances. The non-polar stationary phase can generate adsorption force (such as dispersion force or van der Waals force) on the non-polar compounds, so that the stationary phase layer 201 can adsorb the components of the substance to be tested that is passed into the capillary 20 to the stationary phase layer 201. The heating element 30 heats the capillary 20, so that the temperature of the capillary 20 increases. During the heating process, the components in the substance to be tested will be converted into volatile gases when reaching their own boiling points. The components converted into volatile gases are discharged from the capillary 20 through the sample outlet 22 of the capillary 20, so that the detector in the gas chromatograph can detect the discharged volatile gases to determine the specific type of the volatile gases. When the capillary 20 is heated to the target temperature, all the components adsorbed on the stationary phase layer 201 are converted into volatile gases and discharged from the capillary 20 through the sample outlet 22, thereby separating the multiple components in the substance to be tested whose boiling points are ≤ the target temperature, specifically, separating the multiple components with boiling points between 50°C and 200°C. The design of the metal layer 202 of the capillary 20 can effectively improve the heating rate of the capillary 20, so that the heating element 30 can heat the capillary 20 to the target temperature within 5s to 15s, thereby meeting the use requirements of the portable gas chromatograph for fast heating and fast separation speed. In addition, the metal layer 202 has low resistance and low power consumption required for heating to the target temperature, which can effectively reduce the analysis cost.

[0076] In some embodiments, the components in the substance to be tested are polar compounds. Accordingly, the stationary phase in the stationary phase layer 201 is a polar stationary phase. Specifically, the polar stationary phase includes polymethylsiloxane containing 50 wt % phenyl, thereby adsorbing the polar components in the substance to be tested introduced into the capillary 20 .

[0077] In some embodiments, the target temperature is 200° C., which corresponds to the upper boiling point temperature of volatile organic compounds with a boiling point of 50° C. to 200° C., thereby avoiding waste of power consumption due to an excessively high target temperature.

[0078] In some embodiments, the heating rate of the capillary 20 is 15°C / s to 25°C / s. Specifically, the heating rate of the capillary 20 is any value among 15°C / s, 16°C / s, 17°C / s, 18°C / s, 19°C / s, 20°C / s, 21°C / s, 22°C / s, 23°C / s, 24°C / s and 25°C / s or any value in the range of values ​​composed of any two values. The outer wall of the capillary 20 is a structural design of the metal layer 202, so that the resistance of the capillary 20 is small, and the heating element 30 has a good effect on the capillary 20. When the capillary 20 is electrically heated, the current flowing through the capillary 20 is relatively large, thereby effectively improving the heating rate of the capillary 20. When the heating rate of the capillary 20 is within the above range, the capillary 20 can be heated to the target temperature within 5s to 15s. Specifically, the capillary 20 can be heated to the target temperature within any value of 5s, 6s, 7s, 8s, 9s, 10s, 11s, 12s, 13s, 14s and 15s, or within any value in the range composed of any two values.

[0079] In some embodiments, the temperature rise rate of the capillary 20 is 20° C. / s, and the capillary 20 can be heated to the target temperature of 200° C. within 10 seconds.

[0080] In some embodiments, the length of the capillary 20 is 0.8m to 1.2m, and specifically, the length of the capillary 20 can be any value among 0.8m, 0.9m, 1.0m, 1.1m and 1.2m, or any value in a range of values ​​consisting of any two values. When the length of the capillary 20 is within the above range, the length of the capillary 20 is relatively short, and combined with the structural design that the capillary 20 is spirally laid on the support surface 11 of the support 10, the capillary 20 can still ensure sufficient contact between the internal stationary phase layer 201 and the substance to be tested when the length is relatively short, thereby ensuring the separation effect of the substance to be tested passing into the capillary 20.

[0081] In some embodiments, the length of capillary tube 20 is 1.0 m.

[0082] In some embodiments, the inner diameter of the capillary 20 is 0.2 mm to 0.3 mm, and specifically, the inner diameter of the capillary 20 can be any value among 0.2 mm, 0.21 mm, 0.22 mm, 0.23 mm, 0.24 mm, 0.25 mm, 0.26 mm, 0.27 mm, 0.28 mm, 0.29 mm and 0.3 mm, or any value in the range of values ​​composed of any two values. When the inner diameter of the capillary 20 is within the above range, the flow rate of the substance to be tested introduced into the capillary 20 can be guaranteed, so that within 5s to 15s of the time when the capillary 20 is heated to the target temperature, a sufficient amount of the substance to be tested can be introduced into the capillary 20, thereby ensuring the amount of the components separated by the stationary phase layer 201, and further ensuring the accuracy of the subsequent detection of the separated components.

[0083] In some embodiments, the inner diameter of the capillary 20 is 0.26 mm.

[0084] In some embodiments, reference Figure 1 , Figure 4-5 The gas chromatography column 100 further includes two insulating films 40, the two insulating films 40 are spaced apart, specifically, the two insulating films 40 are spaced apart along the third direction Z of the support 10, the capillary 20 is disposed between the two insulating films 40, and the two insulating films 40 cooperate to form a clamp for the capillary 20, referring to Figure 4 The injection end 21 and the discharge end 22 of the capillary 20 extend outward from the insulating film 40 respectively. The design of the insulating film 40 can form an insulating coating for the capillary 20. The insulating film 40 is attached to the surface of the capillary 20. While ensuring the shape stability of the capillary 20 laid in a spiral shape, it prevents the capillary 20 from short-circuiting during the heating process, thereby ensuring the safety and stability of the gas chromatography column 100.

[0085] In some embodiments, the temperature resistance of the insulating film 40 is higher than the target temperature. Specifically, the material of the insulating film 40 is a high temperature resistant insulating material, thereby preventing the insulating film 40 from being damaged during the process of the capillary 20 heating up to the target temperature or after reaching the target temperature, thereby ensuring the insulation effect.

[0086] In some embodiments, the temperature resistance of the insulating film 40 is 300° C., which is 200° C. higher than the target temperature of the capillary 20 .

[0087] In some embodiments, reference Figure 1 to Figure 5 The capillary 20 further includes a sleeve 23, which is sleeved on the sample outlet 22. Specifically, refer to Figure 5-6The injection end 21 and the sample outlet end 22 are located on the same side of the capillary 20. Specifically, the injection end 21 and the sample outlet end 22 are located on the same side of the capillary 20 along the first direction X. This causes part of the sample outlet end 22 to overlap with the capillary 20 that is spirally wound along the third direction Z, thereby posing a risk of short circuit. The provision of the sleeve 23 can avoid the risk of short circuit in the capillary 20 and ensure the safety of the capillary 20.

[0088] In some embodiments, reference Figure 1-2 as well as Figure 4-5 The gas chromatography column 100 further includes a temperature measuring element 50, which is connected to the capillary 20 to measure the temperature of the capillary 20. Specifically, the temperature measuring element 50 is disposed between the two insulating films 40, and one end of the temperature measuring element 50 is connected to the capillary 20 to measure the temperature of the capillary 20, thereby improving the accuracy of the temperature control of the capillary 20.

[0089] In some embodiments, the temperature measuring element 50 is a thermocouple.

[0090] In some embodiments, reference Figure 1 and Figure 2 The gas chromatography column 100 further includes an air cooling member 60, which is mounted on the support 10. Specifically, the air cooling member 60 is mounted on a side of the second support plate 102 away from the first support plate 101 along the third direction Z, and the air outlet end of the air cooling member 60 faces the capillary 20. The air cooling member 60 can cool the temperature of the capillary 20 from the target temperature to the initial temperature. The setting of the air cooling member 60 can heat the capillary 20 to the target temperature, complete the separation of the components in the substance to be tested, and then cool the capillary 20 to the initial temperature, so as to facilitate the introduction and separation of the substance to be tested next time.

[0091] In some embodiments, the cooling rate of the capillary 20 is 30°C / s to 50°C / s. Specifically, the cooling rate of the capillary can be any value among 30°C / s, 35°C / s, 40°C / s, 45°C / s and 50°C / s or any value in a range of values ​​consisting of any two values. When the cooling rate of the capillary 20 is within the above range, the capillary 20 can be cooled from the target temperature to the initial temperature in a short time, which is convenient for subsequent analysis and testing of the gas chromatograph and improves the efficiency of analysis and testing.

[0092] In some embodiments, the initial temperature can be room temperature or other temperatures, as long as the initial temperature is lower than the lower limit of the boiling point of the substance to be tested introduced into the capillary 20. For example, if the substance to be tested is a volatile organic compound with a boiling point of 50°C to 200°C, the initial temperature can be lower than 50°C.

[0093] In some embodiments, the air cooling member 60 is a fan.

[0094] In some embodiments, reference Figure 1 to Figure 3 The gas chromatography column 100 also includes a first connecting tube 70 and a second connecting tube 71. The first connecting tube 70 is inserted in the first heating element 31, the injection end 21 of the capillary 20 is inserted in the first connecting tube 70, the second connecting tube 71 is inserted in the second heating element 32, and the sample outlet end 22 of the capillary 20 is inserted in the second connecting tube 71. The design of the first connecting tube 70 and the second connecting tube 71 can form protection for the injection end 21 and the sample outlet end 22, ensure the stability of the substance to be tested entering the capillary 20 through the injection end 21, and ensure the stability of the separated components discharged from the capillary 20 through the sample outlet end 22.

[0095] In some embodiments, reference Figure 1 to Figure 3 The sleeve 23 is sleeved on the sample outlet end 22 , and the sleeve 23 is inserted into the second connecting pipe 71 .

[0096] In some embodiments of the present application, a gas chromatograph 200 is also provided. Figure 8 to Figure 10 The gas chromatograph 200 includes: the gas chromatograph column 100 as described above, an injection port 210 , a valve body 220 , a pretreatment component 230 , a carrier gas source 240 and a detection component 250 .

[0097] Reference Figure 8 to Figure 10 The injection port 210 can be used to pass the substance to be tested. The injection port 210 is in the shape of a tube body. One end of the injection port 210 is connected to the valve body 220. The injection end 21 of the capillary 20 is connected to the valve body 220. The pretreatment component 230 includes an inlet end 231 and an outlet end 232. The inlet end 231 and the outlet end 232 are respectively connected to the valve body 220. The carrier gas source 240 is connected to the valve body 220. The detection component 250 is connected to the sample outlet end 22 of the capillary 20.

[0098] Among them, refer to Fig. 9 The injection port 210 can be connected to the pre-treatment component 230 through the valve body 220 to form a sampling passage. Specifically, the injection port 210 can be connected to the inlet end 231 of the pre-treatment component 230 through the valve body 220 to form a sampling passage. Fig.10 The carrier gas source 240 can be communicated with the inlet end 231 of the pretreatment component 230 through the valve body 220, and the outlet end 232 of the pretreatment component 230 can be communicated with the injection end 21 of the capillary 20 through the valve body 220 to form an injection passage.

[0099] The valve body 220 can switch between the sampling passage and the injection passage. The valve body 220 switches to the sampling passage, and the substance to be tested introduced into the injection port 210 can enter the pretreatment component 230 through the sampling passage (i.e., through the valve body 220 and the pipeline connecting the valve body 220 and the inlet end 231). The pretreatment component 230 can enrich the introduced substance to be tested. The valve body 220 switches to the injection passage, and the carrier gas in the carrier gas source 240 can pass the substance to be tested enriched in the pretreatment component 230 into the capillary 20 through the injection passage. The heating component 30 electrically heats the capillary 20, so that the capillary 20 is heated to the target temperature within 5s to 15s. During the heating process, the stationary phase layer 201 in the capillary 20 can separate multiple components in the substance to be tested introduced into the capillary 20, and the separated components can be discharged to the detection component 250 through the sample outlet end 22. The detection component 250 can analyze and detect the components to generate a chromatogram.

[0100] In some embodiments, the gas chromatograph 200 further includes a pump body 260 , the suction end of which is connected to the valve body 220 , and the pump body 260 can be connected to the sampling passage through the valve body 220 to transport the substance to be tested to the pretreatment part 230 through the inlet 210 and the valve body 220 .

[0101] Specifically, refer to Figure 8 to Figure 10 The valve body 220 is a six-way valve, and the valve body 220 includes a first interface 221, a second interface 222, a third interface 223, a fourth interface 224, a fifth interface 225 and a sixth interface 226 which are arranged at intervals along the circumferential direction of the valve body 220. The injection port 210 is connected to the first interface 221, the inlet end 231 of the pretreatment component 230 is connected to the second interface 222 through a pipeline, the carrier gas source 240 is connected to the third interface 223 through a pipeline, the outlet end 232 of the pretreatment component 230 is connected to the fifth interface 225 through a pipeline, the injection end 21 of the capillary 20 is connected to the fourth interface 224 through a pipeline, and the pump body 260 is connected to the sixth interface 226 of the valve body 220 through a pipeline.

[0102] Reference Fig. 9In the sampling phase, the valve body 220 switches to the sampling path, that is, the valve body 220 connects the first interface 221 with the second interface 222, connects the fifth interface 225 with the sixth interface 226, and disconnects the third interface 223 with the fourth interface 224, so that the injection port 210 is connected to the inlet end 231 of the pretreatment component 230 through the valve body 220, and the pump body 260 is connected to the sampling path. The pump body 260 can suck the substance to be tested from the injection port 210 into the valve body 220 and transport it to the pretreatment component 230 through the second interface 222, so that the pretreatment component 2 30 is used to enrich the introduced substance to be tested, and the amount of the substance to be tested is increased. At this time, there is no connection between the fifth interface 225 connected to the outlet end 232 and the fourth interface 224 connected to the injection end 21 of the capillary 20, which can prevent the substance to be tested enriched in the pretreatment part 230 from entering the capillary 20, ensure the enrichment of the substance to be tested in the pretreatment part 230, and avoid leakage, thereby ensuring the sufficiency of the amount of the substance to be tested introduced into the capillary 20 in the subsequent injection stage, ensuring the sufficiency of the amount of the components separated by the subsequent detection part 250, and ensuring the accuracy of the analysis.

[0103] Reference Fig.10 In the injection stage, the valve body 220 switches to the injection path, that is, the valve body 220 connects the second interface 222 with the third interface 223, connects the fourth interface 224 with the fifth interface 225, and disconnects the first interface 221 from the sixth interface 226, thereby connecting the carrier gas source 240 with the inlet end 231 of the pretreatment element 230 through the valve body 220, and connecting the outlet end 232 of the pretreatment element 230 with the injection end 21 of the capillary 20 through the valve body 220, and the carrier gas source The carrier gas in 240 can pass into the pretreatment component 230 and carry the substance to be tested enriched in the pretreatment component 230 into the capillary 20. The carrier gas will not be adsorbed by the stationary phase layer 201 in the capillary 20 and can be discharged directly. The capillary 20 is heated by the heating component 30 so that the stationary phase layer 201 separates the components in the substance to be tested. The separated components are discharged to the detection component 250 through the sample outlet 22. The components are analyzed and detected by the detection component 250 to generate a chromatogram.

[0104] The sampling passage and the injection passage are switched through the valve body 220, ensuring that the pretreatment component 230 can enrich a sufficient amount of the substance to be tested in the sampling stage and avoid leakage of the substance to be tested, and can ensure that the amount of the substance to be tested introduced into the capillary 20 in the injection stage is sufficient, ensuring that the subsequent detection component 250 detects and separates a sufficient amount of components, ensuring the accuracy of the analysis, and meeting the use requirements of a smaller portable gas chromatograph.

[0105] In some embodiments, the pump body 260 can also discharge impurity gases mixed in the substance to be tested. The pump body 260 forms a negative pressure inside the valve body 220. In addition to volatile organic compounds to be tested, impurity gases such as air can also be sucked into the pretreatment component 230, affecting the purity of the substance to be tested. The pump body 260 can discharge the impurity gases in the pretreatment component 230 through the sampling passage, thereby ensuring the purity of the substance to be tested and the accuracy of subsequent analysis.

[0106] In some embodiments, reference Figure 8 to Figure 10 The gas chromatograph 200 further includes a heating element 270, the inlet end 231 and the outlet end 232 are respectively connected to the heating element 270, and the heating element 270 can electrically heat the pretreatment element 230, so that the pretreatment element 230 can be heated to the target temperature within 1s to 3s. Figure 8 to Figure 10 The heating element 270 includes a first heating element 271 and a second heating element 272. The inlet end 231 is connected to the first heating element 271, and the outlet end 232 is connected to the second heating element 272. The first heating element 271, the second heating element 272 and the pretreatment element 230 can form a loop. The first heating element 271 and the second heating element 272 are respectively electrically connected to the power supply as electrodes, so as to realize the electrical heating of the pretreatment element 230. In the injection stage, when the substance to be tested is a volatile organic compound with a boiling point of 50°C to 200°C, the heating element 270 can heat the pretreatment element 230 to the target temperature of 200°C within 1s to 3s, so that the substances to be tested in the pretreatment element 230 all reach the boiling point and are converted into volatile gases, so that they can be carried to the capillary 20 by the carrier gas for separation, thereby improving the analysis speed and efficiency.

[0107] In some embodiments, the temperature increasing component 270 can increase the temperature of the pre-treatment component 230 to the target temperature within 2 seconds.

[0108] In some embodiments, the carrier gas in the carrier gas source 240 is helium or nitrogen.

[0109] In some embodiments, reference Figure 8 to Figure 10 The pretreatment component 230 also includes a trap 233, which is in the shape of a U-shaped tube, one end of the trap 233 is an inlet end 231, and the other end is an outlet end 232. The trap 233 can adsorb and enrich the substance to be tested. When the trap 233 is heated to the target temperature, the substance to be tested inside can be converted into a volatile gas and passed into the capillary 20 under the action of the carrier gas.

[0110] In some embodiments, reference Figure 8 The pretreatment component 230 further includes an analysis component 234, in which a trap 233 is disposed. The trap 233 cooperates with the analysis component 234 to adsorb and enrich the introduced substance to be tested.

[0111] The present application also provides an analysis method of the gas chromatograph as described above, the analysis method comprising the following steps:

[0112] S1, switching the valve body 220 to the sampling passage;

[0113] S2, passing the substance to be tested into the pretreatment component 230 through the injection port 210 and the valve body 220;

[0114] S3, switching the valve body 220 from the sampling passage to the injection passage;

[0115] S4, passing the carrier gas in the carrier gas source 240 into the pretreatment component 230 through the valve body 220, and passing the substance to be tested in the pretreatment component 230 into the capillary 20 through the valve body 220 through the carrier gas;

[0116] S5, electrically heating the capillary 20 by the heating element 30, so that the capillary 20 is heated to the target temperature within 5s to 15s. During the heating process, the capillary 20 separates multiple components in the substance to be tested, and the separated components are discharged to the detection element 250 through the sample outlet 22;

[0117] S6. Analyze and detect the components through the detection element 250 to generate a chromatogram.

[0118] In some embodiments, step S2 of passing the substance to be tested into the pretreatment component 230 through the injection port 210 via the valve body 220 further includes:

[0119] S21 , the pump body 260 delivers the substance to be tested to the pre-treatment component 230 via the valve body 220 .

[0120] Among them, step S2 is completed within 8s to 12s.

[0121] In some embodiments, the step S3 of switching the valve body from the sampling passage to the injection passage further includes:

[0122] S31 , heating the pretreatment component 230 by the temperature increasing component 270 , so that the pretreatment component 230 is heated to the target temperature within 1 second to 3 seconds.

[0123] In some embodiments, in step S4 of passing the substance to be tested in the pretreatment part 230 through the valve body 220 into the capillary 20 by means of a carrier gas, the flow rate of the carrier gas is 3 mL / min to 5 mL / min. Specifically, the flow rate of the carrier gas can be any value among 3 mL / min, 3.5 mL / min, 4 mL / min, 4.5 mL / min and 5 mL / min or any value in the range of values ​​composed of any two values. When the flow rate of the carrier gas is within the above range, within 5s to 15s of heating to the target temperature, the carrier gas can carry a larger amount of the substance to be tested in the pretreatment part 230 into the capillary 20, thereby ensuring the amount of the components separated by the stationary phase layer 201, and then ensuring the accuracy of the subsequent detection of the separated components.

[0124] In some embodiments, the flow rate of the carrier gas is 4 mL / min.

[0125] In some embodiments, in step S5 of electrically heating the capillary 20 by the heating element 30 , the heating rate of the capillary 20 is 15° C. / s to 25° C. / s.

[0126] In some embodiments, in step S5 of discharging the separated components to the detection part 250 through the sample outlet end 22, the substance to be tested that enters the capillary 20 through the sample outlet end 21 can be discharged from the capillary 20 through the sample outlet end within 15s to 25s. Specifically, since the length of the capillary 20 is short, the flow rate of the carrier gas introduced is large, and the heating rate of the capillary 20 is high, the substance to be tested can be separated in the capillary 20 in a short time and discharged to the detection part 250.

[0127] The following description is made of the analysis method of the gas chromatograph 200 provided in the embodiment of the present application, taking the standard solution of C6-C14 normal alkanes as the object:

[0128] Installing the gas chromatography column 100 into the gas chromatograph 200;

[0129] Reference Fig. 9 In the sampling stage, the valve body 220 is switched to the injection passage, that is, the valve body 220 connects the first interface 221 with the second interface 222, connects the fifth interface 225 with the sixth interface 226, and disconnects the third interface 223 with the fourth interface 224, so that the injection port 210 is connected to the inlet end 231 of the pretreatment component 230 through the valve body 220;

[0130] The pump body 260 is turned on to pump the standard solution of C6-C14 normal alkanes into the pretreatment element 230 through the sample inlet 210, and the pretreatment element 230 adsorbs and enriches the standard solution of C6-C14 normal alkanes;

[0131] Reference Fig.10In the injection stage, the valve body 220 switches to the injection passage, that is, the valve body 220 connects the second interface 222 with the third interface 223, connects the fourth interface 224 with the fifth interface 225, and disconnects the first interface 221 from the sixth interface 226, thereby connecting the carrier gas source 240 with the inlet end 231 of the pretreatment component 230 through the valve body 220, and connecting the outlet end 232 of the pretreatment component 230 with the injection end 21 of the capillary 20 through the valve body 220;

[0132] The pretreatment element 230 is heated by the temperature raising element 270 so that the temperature of the pretreatment element 230 is raised to 200° C. within 2 seconds, so that the standard solution of C6-C14 normal alkanes in the pretreatment element 230 reaches a boiling point and is converted into a volatile gas;

[0133] The helium in the carrier gas source 240 is passed into the pretreatment part 230, and the C6-C14 normal alkanes enriched and converted into volatile gases in the pretreatment part 230 are carried into the capillary 20 by the helium. The temperature of the helium is relatively low. In the process of carrying the volatile gases to the capillary 20, the volatile gases are cooled and restored to a standard solution of C6-C14 normal alkanes;

[0134] The heating element 30 is turned on to heat the capillary 20, so that the temperature of the capillary 20 is increased to 200°C at a rate of 20°C / s within 10s, and the stationary phase layer 201 in the capillary 20 separates the C6-C14 normal alkanes converted into volatile gases, and the separated C6-C14 normal alkanes are discharged from the sample outlet 22 to the detection element 250;

[0135] The detection element 250 completes the analysis and detection of C6-C14 normal alkanes converted into volatile gases within 20 seconds, and generates a chromatogram.

[0136] The concentration of C6-C14 normal alkanes in the standard solution of C6-C14 normal alkanes is 10 ppm, and the solvent is methanol.

[0137] Reference Fig.11 The gas chromatograph 200 provided in the embodiment of the present application can complete the analysis and test of the C6-C14 normal alkane standard solution within 20 seconds. The C6-C14 normal alkanes can be detected normally with clear boundaries between peaks, and the separation effect is good.

[0138] The above is a detailed introduction to a gas chromatography column, a gas chromatograph and an analysis method provided in the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A gas chromatography column, characterized in that: include: A support (10) having a support surface (11); A capillary (20), one end of the capillary (20) being a sample injection end (21), and the other end being a sample outlet end (22), a substance to be tested can enter the capillary (20) through the sample injection end (21), the substance to be tested comprising a plurality of components, the capillary (20) being laid on the support surface (11) in a spiral shape, and along the radial direction of the capillary (20), the capillary (20) comprising a stationary phase layer (201) and a metal layer (202) arranged from the inside to the outside; A heating element (30) is arranged on one side of the support (10), and the sample inlet end (21) and the sample outlet end (22) are respectively connected to the heating element (30); The heating element (30) can electrically heat the capillary (20), so that the capillary (20) is heated to a target temperature within 5 to 15 seconds. During the heating process, the stationary phase layer (201) can separate multiple components in the substance to be tested, and the separated components can be discharged from the capillary (20) through the sample outlet (22).

2. The gas chromatographic column according to claim 1, characterized in that The inner wall surface of the metal layer (202) is treated to be inert to form an inert layer (203), and the stationary phase layer (201) is arranged on the inert layer (203); The substance to be tested includes volatile organic matter, the stationary phase layer (201) includes one of a polar stationary phase and a non-polar stationary phase, the polar stationary phase includes polymethylsiloxane containing 50 wt% of phenyl, and the non-polar stationary phase includes polymethylsiloxane containing 5 wt% of phenyl; The heating rate of the capillary (20) is 15°C / s to 25°C / s.

3. The gas chromatography column according to claim 1, characterized in that The length of the capillary tube (20) is 0.8 m to 1.2 m, and the inner diameter of the capillary tube (20) is 0.2 mm to 0.3 mm; The substance to be tested that enters the capillary tube (20) through the sample injection end (21) can be discharged from the capillary tube (20) through the sample output end (22) within 15 seconds to 25 seconds.

4. The gas chromatographic column according to claim 1, characterized in that The gas chromatographic column further comprises two insulating films (40), the two insulating films (40) are arranged at intervals, the capillary (20) is arranged between the two insulating films (40), and the two insulating films (40) cooperate to form a clamp for the capillary (20); The insulating film (40) has a temperature resistance higher than the target temperature; The sample inlet end (21) and the sample outlet end (22) extend to the outside of the two insulating films (40) respectively; The heating element (30) comprises a first heating element (31) and a second heating element (32); the sample inlet end (21) is connected to the first heating element (31), and the sample outlet end (22) is connected to the second heating element (32).

5. The gas chromatography column according to claim 1, characterized in that The gas chromatographic column further comprises a temperature measuring component (50) and an air cooling component (60); The temperature measuring element (50) is connected to the capillary tube (20) to measure the temperature of the capillary tube (20); The air cooling component (60) is mounted on the support (10), the air outlet end of the air cooling component (60) faces the capillary tube (20), and the air cooling component (60) can reduce the temperature of the capillary tube (20) from the target temperature to the initial temperature; The cooling rate of the capillary (20) is 30°C / s to 50°C / s.

6. A gas chromatograph, characterized in that: The gas chromatograph comprises: The gas chromatography column (100) according to any one of claims 1 to 5; An injection port (210) capable of introducing a substance to be tested; A valve body (220), the injection port (210) is connected to the valve body (220), and the injection end (21) of the capillary tube (20) in the gas chromatography column (100) is connected to the valve body (220); A pre-treatment component (230), the pre-treatment component (230) comprising an inlet end (231) and an outlet end (232), the inlet end (231) and the outlet end (232) being respectively connected to the valve body (220); A carrier gas source (240) connected to the valve body (220); A detection member (250), the sample outlet end (22) of the capillary tube (20) being connected to the detection member (250); The sample inlet (210) can be connected to the pre-treatment component (230) through the valve body (220) to form a sampling passage; The carrier gas source (240) can be connected to the inlet end (231) through the valve body (220), and the outlet end (232) can be connected to the injection end (21) of the capillary tube (20) through the valve body (220), so as to form an injection passage; The valve body (220) is capable of switching between the sampling passage and the injection passage; The valve body (220) is switched to the sampling passage, and the substance to be tested that is introduced into the sampling port (210) can be transported to the pretreatment component (230) through the sampling passage, and the pretreatment component (230) can enrich the substance to be tested; The valve body (220) is switched to the injection passage, and the carrier gas in the carrier gas source (240) can pass the substance to be tested, which is enriched in the pretreatment component (230), into the capillary tube (20) through the injection passage; The heating element (30) in the gas chromatography column (100) can electrically heat the capillary (20), so that the capillary (20) is heated to a target temperature within 5 seconds to 15 seconds. During the heating process, the stationary phase layer (201) in the capillary (20) can separate multiple components in the substance to be tested that passes into the capillary (20), and the separated components can be discharged to the detection element (250) through the sample outlet (22). The detection element (250) can analyze and detect the components to generate a chromatogram.

7. The gas chromatograph according to claim 6, characterized in that The gas chromatograph further comprises a pump body (260), the gas extraction end of the pump body (260) being connected to the valve body (220), and the pump body (260) being capable of being connected to the sampling passage through the valve body (220) so as to transport the substance to be tested to the pretreatment component (230) through the sampling port (210) and the valve body (220); The pump body (260) can also discharge impurity gases mixed in the substance to be tested.

8. The gas chromatograph according to claim 6, characterized in that The valve body (220) comprises a six-way valve.

9. The gas chromatograph according to claim 6, characterized in that: The gas chromatograph further comprises a heating component (270), the inlet end (231) and the outlet end (232) being respectively connected to the heating component (270), the heating component (270) being capable of electrically heating the pretreatment component (230), and the pretreatment component (230) being capable of heating to a target temperature within 1 second to 3 seconds.

10. An analysis method for a gas chromatograph as claimed in claim 6, characterized in that: The analytical method comprises the following steps: Switching the valve body (220) to the sampling passage; Passing the substance to be tested into the pretreatment component (230) through the injection port (210) and the valve body (220); Switching the valve body (220) from a sampling passage to a sampling passage; Passing the carrier gas in the carrier gas source (240) into the pretreatment component (230) via the valve body (220), and passing the substance to be tested in the pretreatment component (230) into the capillary (20) via the valve body (220) through the carrier gas; The capillary (20) is electrically heated by a heating element (30) so that the capillary (20) is heated to a target temperature within 5 to 15 seconds. During the heating process, the capillary (20) separates multiple components in the substance to be tested, and the separated components are discharged to the detection element (250) through the sample outlet (22); The components are analyzed and detected by the detection element (250) to generate a chromatogram.

11. The gas chromatograph analysis method according to claim 10, characterized in that: The step of passing the substance to be tested through the injection port (210) and the valve body (220) into the pretreatment component (230) further includes: The substance to be tested is transported to the pre-treatment component (230) via the pump body (260) through the valve body (220); The step of passing the substance to be tested through the injection port (210) and the valve body (220) into the pretreatment component (230) is completed within 8 seconds to 12 seconds; The step of switching the valve body (220) from the sampling passage to the injection passage also includes: The pre-treatment component (230) is heated by a temperature-increasing component (270), so that the pre-treatment component (230) is heated to a target temperature within 1 second to 3 seconds.

12. The gas chromatograph analysis method according to claim 11, characterized in that: In the step of passing the substance to be tested in the pre-treatment component (230) into the capillary (20) via the valve body (220) by means of a carrier gas, the flow rate of the carrier gas is 3 mL / min to 5 mL / min; In the step of electrically heating the capillary tube (20) by means of a heating element (30), the heating rate of the capillary tube (20) is 15°C / s to 25°C / s; In the step of discharging the separated components to the detection element (250) through the sample outlet end (22), the substance to be detected that enters the capillary (20) through the sample injection end (21) can be discharged from the capillary (20) through the sample outlet end (22) within 15 seconds to 25 seconds.

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