A chromatograph for detecting moisture in NMP and its thermal conductivity detection method

Abstract

The invention discloses a chromatograph for detecting water content in NMP and a thermal conductivity detection method thereof, and the invention relates to the technical field of chromatographs. The chromatograph for detecting water content in NMP and a thermal conductivity detection method thereof, through the arrangement of a limiting component and a sealing component, when the device is sampling, through the cooperation of a limiting plate frame and components such as a limiting pressure plate, a limiting column, and an inner slide rod at the bottom thereof, the sample bottle placed on the top surface of the load-bearing plate can be limited, the stability of subsequent sampling is ensured, and the protection effect and stability of the sample bottle are improved. At the same time, by pressing down the pressure plate, the bottom of the pressure plate can be in contact with and fitted with a gasket ring installed at the end of the corresponding sealing ring. At the same time, when the sealing ring moves downward, the conical gasket plate fixedly installed at the bottom thereof can be sleeved to the corresponding end of the sample bottle, thereby ensuring the sealing effect of the sample bottle when placed and sampled, and ensuring the detection accuracy of the device.

Description

Technical Field

[0001] The invention relates to the technical field of chromatographs, in particular to a chromatograph for detecting water content in NMP and a thermal conductivity detection method thereof. Background Art

[0002] Chromatograph is a device used for chromatographic separation and analysis; it includes a sampling system, a detection system, a recording and data processing system, a temperature control system, and a mobile phase control system, etc.; modern chromatographs are characterized by stability, sensitivity, versatility, and a high degree of automation; there are gas chromatographs, liquid chromatographs, and gel chromatographs, etc.; these chromatographs are widely used in the analysis of certain contents of chemical products and polymer materials. Gel chromatography can also determine the molecular weight and distribution of polymer materials.

[0003] When liquid chromatographs are performing measurements, they usually use automatic samplers for sampling. However, during the liquid extraction process, inaccurate placement of sample bottles and lack of protection may cause tipping over, which will affect the insertion and sampling of the automatic sampler, resulting in deviations in the amount of liquid injected and the detection effect during liquid extraction, reducing the use effect of the equipment and the detection accuracy. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a chromatograph for NMP moisture detection and a thermal conductivity detection method thereof, which solves the problem that the position and protection of the sample bottle are likely to affect the detection effect and detection accuracy of the equipment.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: a chromatograph for detecting moisture in NMP, comprising a body, a sampling mechanism is fixedly installed inside the body, positioning bolts are arranged on both sides of the interior of the sampling mechanism, a placement component is arranged at the lower part of the interior of the sampling mechanism, and a plurality of sample bottles are arranged through the placement component, limiting grooves are symmetrically provided on both sides of the interior of the sampling mechanism, and a sampling component is slidably arranged through the limiting grooves, corresponding slide grooves are provided on both sides of the interior of the sampling mechanism, and a limiting component is slidably arranged between two corresponding slide grooves, the limiting component comprises a limiting plate frame, sliders are fixedly installed at both ends of the limiting plate frame, and The cams are connected to the bottom of the rack and are provided with a plurality of springs, each of which is connected to a pair of locks, and the locks are connected to the bottom of the rack by a plurality of springs. The locks are connected to the bottom of the rack and are provided with a plurality of springs. The locks are connected to the bottom of the rack and are provided with a plurality of springs.

[0006] Preferably, the ends of several of the inner sliding rods are fixedly mounted with sliding columns, and are slidably connected with corresponding limiting columns through the cooperation of the sliding columns, and connecting springs are fixedly mounted between the ends of several of the sliding columns and the insides of the corresponding limiting columns.

[0007] Preferably, several of the limit pressure plates are slidably installed at the bottom of the limit plate rack through the cooperation of corresponding limit columns and inner sliding rods, and the installation positions correspond to the sample bottles at the bottom. The several limit pressure plates are symmetrical to each other and are always perpendicular to the horizontal plane.

[0008] Preferably, the sealing assembly includes a sealing ring, which is fixedly installed inside the corresponding limit plate frame, and the inner top surfaces of several of the sealing rings are fixedly installed with gaskets, and the inner bottoms of several of the sealing rings are fixedly installed with conical gaskets, and the central axis of the sealing ring, the corresponding gasket and the conical gasket are the same.

[0009] Preferably, the installation position heights of several of the gaskets are higher than the corresponding sealing rings and the limiting plate frames.

[0010] Preferably, the placement assembly includes a load-bearing plate, which is slidably installed inside the sampling mechanism, and a pull plate is fixedly installed in the middle of the side of the load-bearing plate. Both ends of the side of the load-bearing plate are provided with clamping plates, and the clamping plates on both sides are slidably installed up and down on both sides of the interior of the sampling mechanism, and reset springs are fixedly installed between the bottom of the two clamping plates and the inner sides of the sampling mechanism, and a plurality of limiting sleeves are fixedly installed on the top surface of the load-bearing plate.

[0011] Preferably, the sampling component includes a pressure plate, slides are fixedly installed on both sides of the pressure plate, and are slidably installed inside the sampling mechanism by cooperating between the slides and limit grooves, limit blocks are fixedly installed on both sides of the interior of the sampling mechanism, spring bodies are fixedly installed between the slides on both sides and the bottoms of the corresponding limit blocks, a hydraulic cylinder is fixedly installed inside the sampling mechanism, and the other end of the hydraulic cylinder is fixedly connected to the middle of the top surface of the pressure plate, a plurality of through holes are opened inside the pressure plate, and sampling tubes are fixedly installed inside a plurality of the through holes, a plurality of connectors are fixedly installed on the top surface of the sampling mechanism, elastic connecting tubes are fixedly installed on one end of a plurality of the sampling tubes, and the other ends of the elastic connecting tubes are fixedly connected to the end of the connector, and a filter assembly is provided at the other end of the sampling tube.

[0012] Preferably, the filter assembly includes a sealing head, the outer side of the sealing head is provided with a threaded groove, and the sealing head is fixedly mounted on the end of the corresponding sampling tube by means of a threaded connection, a filter layer is installed inside the sealing head, and a plurality of honeycomb holes are symmetrically provided at the end.

[0013] The present invention also discloses a thermal conductivity detection method of a chromatograph for detecting the moisture content of NMP, which specifically comprises the following steps:

[0014] S1. Sample preparation: Weigh N-methylpyrrolidone (hereinafter referred to as NMP) and a diluted solution on an electronic balance, and use the diluted solution as a solvent and NMP as a solute to prepare a standard mother solution with a concentration of C0; use the same solution as above as a solvent to dilute the obtained standard mother solution step by step to obtain several groups of standard solutions with known concentrations, and the concentrations are recorded as C1, C2, C3, ..., Cn, respectively; then take equal amounts of the above standard solutions with concentrations of C1, C2, C3, ..., Cn into sample bottles, and add equal amounts of tetrahydrofuran into the sample bottles to shake and dissolve, to obtain standard injection solutions;

[0015] S2, sampling: the sample bottles containing the injection liquid are placed into the corresponding limiting sleeves according to the marked concentrations, and then the sample bottles are positioned by pushing the bearing plate into the body until they pass over the card plate and are lifted up by the reset spring, and then the injection tubes inside the body are respectively connected to several connectors on the top surface of the injection mechanism. When sampling, the hydraulic cylinder is first operated to drive the pressure plate to move downward along the limiting grooves through the slides on both sides, so that it drives several sampling tubes to move downward and insert into the corresponding sample bottles, so as to extract the internal solution;

[0016] When the pressure plate is driven by the hydraulic cylinder to move downward, it can contact the limit plate racks on both sides of the sample injection mechanism, so that the corresponding limit plate rack can slide down along the slide groove through pressure and the sliders on both sides until the limit pressure plate installed at the bottom is sleeved to the top of the corresponding sample bottle, and then the limit plate rack continues to move downward, so that the inner sliding rods on both sides of the top surface of the limit pressure plate are pressed into the corresponding limit column, squeezing the corresponding connecting spring to achieve the positioning of the sample bottle. At the same time, when the limit plate rack moves downward, it can also drive the sealing ring to move downward until the conical pad fixedly installed at the bottom of the sealing ring is sleeved to the corresponding end of the sample bottle, and through the downward pressure of the pressure plate, its bottom can contact and fit with the pad ring installed at the end of the corresponding sealing ring to ensure the sealing effect of the sample bottle. When sampling, the solution can enter the sampling tube through the filter layer and the honeycomb hole at the end of the corresponding sampling tube, and then enter the body after the elastic connecting tube and the connector.

[0017] S3, sample detection: set the machine body that has been started and preheated to SIM mode (i.e. select thermal conductivity detection), and set relevant test parameters; after the setting of each test parameter is completed, collect chromatographic peaks according to the set parameters, and save the numerical records.

[0018] Preferably, when placing the sample bottle in S2, the inner diameter of the limiting sleeve is the same as the diameter of the sample bottle, and before placement, it is necessary to avoid foreign matter inside the limiting sleeve causing different heights of the sample bottle.

[0019] Beneficial Effects

[0020] The present invention provides a chromatograph for detecting moisture in NMP and a thermal conductivity detection method thereof. Compared with the prior art, it has the following beneficial effects:

[0021] (1) The chromatograph for detecting moisture in NMP and its thermal conductivity detection method, through the setting of the limiting component and the sealing component, when the equipment is in the process of sampling, through the cooperation of the limiting plate frame and the limiting pressure plate, limiting column, inner slide rod and other components at the bottom thereof, the sample bottle placed on the top surface of the load-bearing plate can be limited, thereby ensuring the stability of subsequent sampling and improving the protection effect and stability of the sample bottle. At the same time, by pressing down the pressure plate, the bottom of the pressure plate can contact and fit with the gasket installed at the end of the corresponding sealing ring. At the same time, when the sealing ring moves downward, the conical gasket fixedly installed at the bottom can be sleeved onto the corresponding end of the sample bottle, thereby ensuring the sealing effect of the sample bottle when it is placed and sampled, and ensuring the detection accuracy of the equipment.

[0022] (2) The chromatograph and thermal conductivity detection method for detecting moisture in NMP can first pass through the filter layer and honeycomb holes at the end of the corresponding sampling tube, then enter the sampling tube, and then enter the body through the elastic connecting tube and the connector, so as to filter the impurities contained in the sample bottle and ensure the subsequent detection effect. At the same time, through the setting of the load-bearing plate and the card plates at both ends of the outer side, the load-bearing plate can be pulled out by pressing the card plate during disassembly. At the same time, the cooperation of the positioning bolt also facilitates the disassembly of the sampling mechanism, which is convenient for subsequent equipment maintenance, cleaning and replacement. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0024] Figure 2 It is a schematic diagram of the structure of the sample injection mechanism of the present invention;

[0025] Figure 3 It is a schematic diagram of the cross-sectional structure of the sample injection mechanism of the present invention;

[0026] Figure 4 This is a schematic diagram of the structure of the pressure plate of the present invention;

[0027] Figure 5 This is a schematic diagram of the structure of the load-bearing plate and the sample bottle of the present invention;

[0028] Figure 6 It is a schematic diagram of the structure of the limit assembly of the present invention;

[0029] Figure 7 For the present invention Figure 6 Schematic diagram of the cross-section structure;

[0030] Figure 8 This is a schematic diagram of the enlarged structure of point A of the present invention;

[0031] Fig. 9 This is a schematic diagram of the cross-sectional structure of the sampling tube of the present invention;

[0032] Fig.10 It is a schematic diagram of the process of the present invention.

[0033] In the figure: 1, machine body; 2, sample injection mechanism; 201, positioning bolt; 202, joint; 203, slide groove; 204, limit groove; 205, limit block; 2051, spring body; 3, load-bearing plate; 301, pull plate; 302, clamping plate; 303, return spring; 304, limit sleeve; 4, sample bottle; 5, pressure plate; 501, hydraulic cylinder; 502, through hole; 503, slide plate; 6, sampling tube; 601, elastic connecting pipe; 602, sealing head; 6021, threaded groove; 6022, filter layer; 6023, honeycomb hole; 7, limit plate frame; 701, slider; 702, support spring; 8, limit pressure plate; 801, rubber pad; 9, limit column; 10, inner slide rod; 1001, slide column; 1002, connecting spring; 11, sealing ring; 1101, gasket; 1102, conical pad. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] See also Figure 1-10 The present invention provides two technical solutions, which specifically include the following steps:

[0036] Embodiment 1:

[0037] A chromatograph for detecting water content in NMP, comprising a body 1, a sampling mechanism 2 is fixedly installed inside the body 1, positioning bolts 201 are arranged on both sides of the sampling mechanism 2, a placement component is arranged below the sampling mechanism 2, and a plurality of sample bottles 4 are arranged through the placement component, limiting grooves 204 are symmetrically arranged on both sides of the sampling mechanism 2, and a sampling component is slidably arranged through the limiting grooves 204, corresponding slide grooves 203 are arranged on both sides of the sampling mechanism 2, and limiting components are slidably arranged between two corresponding slide grooves 203, and the limiting components include a limiting plate frame 7, and sliders 701 are fixedly installed at both ends of the limiting plate frame 7, and the sliders 701 and the slide grooves 203 are respectively moved by the sliders 701 and the slide grooves 203. It is slidably installed on one side of the interior of the sample introduction mechanism 2, and support springs 702 are fixedly installed between the sliders 701 on both sides and the slide grooves 203. A plurality of limit pressing plates 8 are arranged at the bottom of the limit plate frame 7, and a plurality of rubber pads 801 are fixedly installed inside the plurality of limit pressing plates 8. Limiting columns 9 are fixedly installed on both sides of the top surfaces of the plurality of limit pressing plates 8, and inner sliding rods 10 are slidably installed inside the limiting columns 9, and the other ends of the plurality of inner sliding rods 10 are respectively fixedly connected to the bottom of the corresponding limit plate frame 7, and a plurality of sealing components are arranged inside the limit plate frame 7, and the installation positions of the plurality of sealing components correspond one by one to the installation positions of the plurality of limit pressing plates 8 and the plurality of sample bottles 4 respectively.

[0038] In the embodiment of the present invention, the ends of the plurality of inner slide bars 10 are fixedly mounted with slide columns 1001, and are respectively slidably connected with the corresponding limit columns 9 through the cooperation of the slide columns 1001, and connecting springs 1002 are fixedly mounted between the ends of the plurality of slide columns 1001 and the insides of the corresponding limit columns 9, and the plurality of limit pressing plates 8 are respectively slidably mounted on the bottom of the limit plate frame 7 through the cooperation of the corresponding limit columns 9 and the inner slide bars 10, and the mounting positions correspond to the sample bottles 4 at the bottom, and the plurality of limit pressing plates 8 are symmetrical with each other and are always perpendicular to the horizontal plane;

[0039] In the embodiment of the present invention, the sealing assembly includes a sealing ring 11, which is fixedly installed inside the corresponding limiting plate frame 7, and a gasket 1101 is fixedly installed on the inner top surface of several sealing rings 11, and a conical gasket 1102 is fixedly installed on the inner bottom of several sealing rings 11. The central axis of the sealing ring 11 and the corresponding gasket 1101 and the conical gasket 1102 is the same, and the installation position height of several gaskets 1101 exceeds the corresponding sealing ring 11 and the limiting plate frame 7;

[0040] In the embodiment of the present invention, the placement component includes a load-bearing plate 3, which is slidably installed inside the sample injection mechanism 2, and a pull plate 301 is fixedly installed in the middle of the side of the load-bearing plate 3, and clamping plates 302 are provided at both ends of the side of the load-bearing plate 3. The clamping plates 302 on both sides are respectively slidably installed up and down on both sides of the inside of the sample injection mechanism 2, and reset springs 303 are fixedly installed between the bottoms of the two clamping plates 302 and the inner sides of the sample injection mechanism 2, and a plurality of limiting sleeves 304 are fixedly installed on the top surface of the load-bearing plate 3;

[0041] In the embodiment of the present invention, the sampling assembly includes a pressure plate 5, and slide plates 503 are fixedly installed on both sides of the pressure plate 5, and are respectively slidably installed in the interior of the sampling mechanism 2 through the cooperation of the slide plates 503 and the limiting grooves 204. The limiting blocks 205 are fixedly installed on both sides of the interior of the sampling mechanism 2, and spring bodies 2051 are fixedly installed between the slide plates 503 on both sides and the bottoms of the corresponding limiting blocks 205. A hydraulic cylinder 501 is fixedly installed in the interior of the sampling mechanism 2, and the other end of the hydraulic cylinder 501 is fixedly connected to the middle of the top surface of the pressure plate 5. A plurality of through holes 502 are opened in the interior of the pressure plate 5, and the inner portions of the plurality of through holes 502 are A sampling tube 6 is fixedly installed on each part, a plurality of connectors 202 are fixedly installed on the top surface of the sampling mechanism 2, an elastic connecting tube 601 is fixedly installed on one end of each of the sampling tubes 6, and the other end of the elastic connecting tube 601 is fixedly connected to the end of the connector 202, a filter assembly is arranged on the other end of each of the sampling tubes 6, the filter assembly comprises a sealing head 602, a threaded groove 6021 is provided on the outer side of the sealing head 602, and the sealing head 602 is fixedly installed on the end of the corresponding sampling tube 6 by threaded connection, a filter layer 6022 is installed inside the sealing head 602, and a plurality of honeycomb holes 6023 are symmetrically provided on the end.

[0042] The embodiment of the present invention also discloses a thermal conductivity detection method of a chromatograph for detecting the moisture content of NMP, which specifically comprises the following steps:

[0043] S1. Sample preparation: Weigh N-methylpyrrolidone (hereinafter referred to as NMP) and a diluted solution on an electronic balance, and mix the diluted solution as a solvent and NMP as a solute to obtain a standard mother solution with a concentration of C0; dilute the obtained standard mother solution step by step with the same solution as above as a solvent to obtain several groups of standard solutions with known concentrations, and the concentrations are respectively recorded as C1, C2, C3, ..., Cn, and then take equal amounts of the above standard solutions with concentrations of C1, C2, C3, ..., Cn into a sample bottle 4, and add equal amounts of tetrahydrofuran into the sample bottle 4 to shake and dissolve, to obtain a standard injection solution;

[0044] S2, sampling: the sample bottles 4 containing the injection liquid are placed into the corresponding limiting sleeves 304 in sequence according to the marked concentration, and then the sample bottles 4 are positioned by pushing the load-bearing plate 3 into the body 1 until they pass over the clamping plate 302 and are lifted by the reset spring 303, and then the injection tubes in the body 1 are respectively connected to the several connectors 202 on the top surface of the injection mechanism 2. When sampling, the hydraulic cylinder 501 is first operated to drive the pressure plate 5 to move downward along the limiting groove 204 through the slides 503 on both sides, so that it drives the several sampling tubes 6 to move downward and insert into the corresponding sample bottles 4, so as to extract the internal solution;

[0045] When the pressure plate 5 is driven by the hydraulic cylinder 501 to move downward, it can contact the limiting plate frames 7 on both sides of the sample injection mechanism 2, so that the corresponding limiting plate frames 7 slide down along the slide groove 203 through pressure and the sliders 701 on both sides, until the limiting pressure plate 8 installed at the bottom is sleeved to the top of the corresponding sample bottle 4, and then the limiting plate frame 7 continues to move downward, so that the inner sliding rods 10 on both sides of the top surface of the limiting pressure plate 8 are pressed into the corresponding limiting columns 9, and the corresponding connecting springs 1002 are squeezed to realize the positioning of the sample bottle 4. When the plate rack 7 moves downward, it can also drive the sealing ring 11 to move downward until the conical pad 1102 fixedly installed at the bottom of the sealing ring 11 is sleeved onto the corresponding end of the sample bottle 4. By pressing down the pressure plate 5, the bottom of the sealing ring 11 can contact and fit with the pad 1101 installed at the end of the corresponding sealing ring 11, thereby ensuring the sealing effect of the sample bottle 4. When sampling, the solution can enter the sampling tube 6 through the filter layer 6022 and the honeycomb hole 6023 at the end of the corresponding sampling tube 6, and then enter the interior of the body 1 through the elastic connecting tube 601 and the connector 202.

[0046] S3, sample detection: set the machine body 1 that has been started and preheated to SIM mode (i.e. select thermal conductivity detection), and set relevant test parameters; after the setting of each test parameter is completed, collect chromatographic peaks according to the set parameters, and record and save the numerical values.

[0047] In the embodiment of the present invention, when the sample bottle 4 is placed in S2, the inner diameter of the limiting sleeve 304 is the same as the diameter of the sample bottle 4, and before placement, foreign matter inside the limiting sleeve 304 should be avoided to prevent the sample bottle 4 from having different heights.

[0048] Embodiment 2:

[0049] A chromatograph for detecting water content in NMP, comprising a body 1, a sampling mechanism 2 is fixedly installed inside the body 1, positioning bolts 201 are arranged on both sides of the sampling mechanism 2, a placement component is arranged below the sampling mechanism 2, and a plurality of sample bottles 4 are arranged through the placement component, limiting grooves 204 are symmetrically arranged on both sides of the sampling mechanism 2, and a sampling component is slidably arranged through the limiting grooves 204, corresponding slide grooves 203 are arranged on both sides of the sampling mechanism 2, and limiting components are slidably arranged between two corresponding slide grooves 203, and the limiting components include a limiting plate frame 7, and sliders 701 are fixedly installed at both ends of the limiting plate frame 7, and the sliders 701 and the slide grooves 203 are respectively moved by the sliders 701 and the slide grooves 203. It is slidably installed on one side of the interior of the sample introduction mechanism 2, and support springs 702 are fixedly installed between the sliders 701 on both sides and the slide grooves 203. A plurality of limit pressing plates 8 are arranged at the bottom of the limit plate frame 7, and a plurality of rubber pads 801 are fixedly installed inside the plurality of limit pressing plates 8. Limiting columns 9 are fixedly installed on both sides of the top surfaces of the plurality of limit pressing plates 8, and inner sliding rods 10 are slidably installed inside the limiting columns 9, and the other ends of the plurality of inner sliding rods 10 are respectively fixedly connected to the bottom of the corresponding limit plate frame 7, and a plurality of sealing components are arranged inside the limit plate frame 7, and the installation positions of the plurality of sealing components correspond one by one to the installation positions of the plurality of limit pressing plates 8 and the plurality of sample bottles 4 respectively.

[0050] In the embodiment of the present invention, the ends of the plurality of inner slide bars 10 are fixedly mounted with slide columns 1001, and are respectively slidably connected with the corresponding limit columns 9 through the cooperation of the slide columns 1001, and connecting springs 1002 are fixedly mounted between the ends of the plurality of slide columns 1001 and the insides of the corresponding limit columns 9, and the plurality of limit pressing plates 8 are respectively slidably mounted on the bottom of the limit plate frame 7 through the cooperation of the corresponding limit columns 9 and the inner slide bars 10, and the mounting positions correspond to the sample bottles 4 at the bottom, and the plurality of limit pressing plates 8 are symmetrical with each other and are always perpendicular to the horizontal plane;

[0051] In the embodiment of the present invention, the placement component includes a load-bearing plate 3, which is slidably installed inside the sample injection mechanism 2, and a pull plate 301 is fixedly installed in the middle of the side of the load-bearing plate 3, and clamping plates 302 are provided at both ends of the side of the load-bearing plate 3. The clamping plates 302 on both sides are respectively slidably installed up and down on both sides of the inside of the sample injection mechanism 2, and reset springs 303 are fixedly installed between the bottoms of the two clamping plates 302 and the inner sides of the sample injection mechanism 2, and a plurality of limiting sleeves 304 are fixedly installed on the top surface of the load-bearing plate 3;

[0052] In the embodiment of the present invention, the sampling assembly includes a pressure plate 5, and slide plates 503 are fixedly installed on both sides of the pressure plate 5, and are respectively slidably installed in the interior of the sampling mechanism 2 through the cooperation of the slide plates 503 and the limiting grooves 204. The limiting blocks 205 are fixedly installed on both sides of the interior of the sampling mechanism 2, and spring bodies 2051 are fixedly installed between the slide plates 503 on both sides and the bottoms of the corresponding limiting blocks 205. A hydraulic cylinder 501 is fixedly installed in the interior of the sampling mechanism 2, and the other end of the hydraulic cylinder 501 is fixedly connected to the middle of the top surface of the pressure plate 5. A plurality of through holes 502 are opened in the interior of the pressure plate 5, and the inner portions of the plurality of through holes 502 are A sampling tube 6 is fixedly installed on each part, a plurality of connectors 202 are fixedly installed on the top surface of the sampling mechanism 2, an elastic connecting tube 601 is fixedly installed on one end of each of the sampling tubes 6, and the other end of the elastic connecting tube 601 is fixedly connected to the end of the connector 202, a filter assembly is arranged on the other end of each of the sampling tubes 6, the filter assembly comprises a sealing head 602, a threaded groove 6021 is provided on the outer side of the sealing head 602, and the sealing head 602 is fixedly installed on the end of the corresponding sampling tube 6 by threaded connection, a filter layer 6022 is installed inside the sealing head 602, and a plurality of honeycomb holes 6023 are symmetrically provided on the end.

[0053] The embodiment of the present invention also discloses a thermal conductivity detection method of a chromatograph for detecting the moisture content of NMP, which specifically comprises the following steps:

[0054] S1. Sample preparation: Weigh N-methylpyrrolidone (hereinafter referred to as NMP) and a diluted solution on an electronic balance, and mix the diluted solution as a solvent and NMP as a solute to obtain a standard mother solution with a concentration of C0; dilute the obtained standard mother solution step by step with the same solution as above as a solvent to obtain several groups of standard solutions with known concentrations, and the concentrations are respectively recorded as C1, C2, C3, ..., Cn, and then take equal amounts of the above standard solutions with concentrations of C1, C2, C3, ..., Cn into a sample bottle 4, and add equal amounts of tetrahydrofuran into the sample bottle 4 to shake and dissolve, to obtain a standard injection solution;

[0055] S2, sampling: the sample bottles 4 containing the injection liquid are placed into the corresponding limiting sleeves 304 in sequence according to the marked concentration, and then the sample bottles 4 are positioned by pushing the load-bearing plate 3 into the body 1 until they pass over the clamping plate 302 and are lifted by the reset spring 303, and then the injection tubes in the body 1 are respectively connected to the several connectors 202 on the top surface of the injection mechanism 2. When sampling, the hydraulic cylinder 501 is first operated to drive the pressure plate 5 to move downward along the limiting groove 204 through the slides 503 on both sides, so that it drives the several sampling tubes 6 to move downward and insert into the corresponding sample bottles 4, so as to extract the internal solution;

[0056] When the pressure plate 5 is driven by the hydraulic cylinder 501 to move downward, it can contact the limiting plate frames 7 on both sides of the sample injection mechanism 2, so that the corresponding limiting plate frames 7 slide down along the slide groove 203 through pressure and the sliders 701 on both sides, until the limiting pressure plate 8 installed at the bottom is sleeved on the top of the corresponding sample bottle 4, and then the limiting plate frame 7 continues to move downward, so that the inner sliding rods 10 on both sides of the top surface of the limiting pressure plate 8 are pressed into the corresponding limiting columns 9, and the corresponding connecting springs 1002 are squeezed to achieve the positioning of the sample bottle 4. When sampling, the solution can enter the sampling tube 6 through the filter layer 6022 and the honeycomb hole 6023 at the end of the corresponding sampling tube 6, and then enter the body 1 through the elastic connecting tube 601 and the connector 202.

[0057] S3, sample detection: set the machine body 1 that has been started and preheated to SIM mode (i.e. select thermal conductivity detection), and set relevant test parameters; after the setting of each test parameter is completed, collect chromatographic peaks according to the set parameters, and record and save the numerical values.

[0058] In the embodiment of the present invention, when the sample bottle 4 is placed in S2, the inner diameter of the limiting sleeve 304 is the same as the diameter of the sample bottle 4, and before placement, foreign matter inside the limiting sleeve 304 should be avoided to prevent the sample bottle 4 from having different heights.

[0059] Meanwhile, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0060] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0061] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A chromatograph for detecting water content in NMP, comprising a body (1), wherein a sample introduction mechanism (2) is fixedly installed inside the body (1), and positioning bolts (201) are arranged on both sides of the sample introduction mechanism (2), characterized in that: A placement component is arranged at the lower part of the sample injection mechanism (2), and a plurality of sample bottles (4) are arranged through the placement component. Limiting grooves (204) are symmetrically provided on both sides of the sample injection mechanism (2), and a sampling component is slidably provided through the limiting grooves (204). Corresponding slide grooves (203) are arranged on both sides of the sample injection mechanism (2), and a limiting component is slidably provided between two corresponding slide grooves (203); The limiting assembly comprises a limiting plate frame (7), both ends of which are fixedly mounted with sliders (701), and are respectively slidably mounted on one side of the interior of the sample introduction mechanism (2) through the cooperation of the sliders (701) and the slide grooves (203), and support springs (702) are fixedly mounted between the sliders (701) and the slide grooves (203) on both sides, and a plurality of limiting pressure plates (8) are arranged at the bottom of the limiting plate frame (7), and a plurality of limiting pressure plates (8) are fixedly mounted inside the plurality of limiting pressure plates (8). A rubber pad (801), both sides of the top surfaces of the plurality of limit pressure plates (8) are fixedly installed with limit columns (9), and the insides of the limit columns (9) are slidably installed with inner sliding rods (10), and the other ends of the plurality of inner sliding rods (10) are respectively fixedly connected to the bottom of the corresponding limit plate frame (7), and the inside of the limit plate frame (7) is provided with a plurality of sealing components, and the installation positions of the plurality of sealing components correspond to the installation positions of the plurality of limit pressure plates (8) and the plurality of sample bottles (4) respectively; The ends of the plurality of inner sliding rods (10) are fixedly mounted with sliding columns (1001), and are respectively slidably connected with the corresponding limiting columns (9) through the cooperation of the sliding columns (1001); connecting springs (1002) are fixedly mounted between the ends of the plurality of sliding columns (1001) and the insides of the corresponding limiting columns (9); the plurality of limiting pressure plates (8) are slidably mounted on the bottom of the limiting plate frame (7) through the cooperation of the corresponding limiting columns (9) and the inner sliding rods (10), and the mounting positions correspond to the sample bottles (4) at the bottom; the plurality of limiting pressure plates (8) are symmetrical with each other and are always parallel to the horizontal plane; The sealing assembly comprises a sealing ring (11), wherein the sealing ring (11) is fixedly mounted inside a corresponding limiting plate frame (7), a gasket (1101) is fixedly mounted on the inner top surface of a plurality of the sealing rings (11), a conical gasket (1102) is fixedly mounted on the inner bottom of a plurality of the sealing rings (11), the sealing ring (11) and the corresponding gasket (1101) and the conical gasket (1102) have the same central axis, and the installation position height of the plurality of gaskets (1101) exceeds the corresponding sealing ring (11) and the limiting plate frame (7); The placement assembly comprises a load-bearing plate (3), the load-bearing plate (3) being slidably mounted inside the sample injection mechanism (2), a pull plate (301) being fixedly mounted in the middle of the side surface of the load-bearing plate (3), a clamping plate (302) being provided at both ends of the side surface of the load-bearing plate (3), the clamping plates (302) on both sides being slidably mounted up and down on both sides of the inside of the sample injection mechanism (2), a return spring (303) being fixedly mounted between the bottom of the two clamping plates (302) and both sides of the inside of the sample injection mechanism (2), and a plurality of limiting sleeves (304) being fixedly mounted on the top surface of the load-bearing plate (3); The sampling assembly comprises a pressure plate (5), slide plates (503) are fixedly mounted on both sides of the pressure plate (5), and are respectively slidably mounted inside the sample introduction mechanism (2) through the cooperation of the slide plates (503) and the limiting grooves (204), and limiting blocks (205) are fixedly mounted on both sides of the sample introduction mechanism (2), and spring bodies (2051) are fixedly mounted between the slide plates (503) on both sides and the bottoms of the corresponding limiting blocks (205), and a hydraulic cylinder (501) is fixedly mounted inside the sample introduction mechanism (2), and the hydraulic cylinder (501) The other end of the sampling mechanism (2) is fixedly connected to the middle of the top surface of the pressure plate (5); a plurality of through holes (502) are provided inside the pressure plate (5); and a plurality of sampling tubes (6) are fixedly installed inside the plurality of through holes (502); a plurality of connectors (202) are fixedly installed on the top surface of the sampling mechanism (2); an elastic connecting tube (601) is fixedly installed at one end of the plurality of sampling tubes (6); and the other end of the elastic connecting tube (601) is fixedly connected to the end of the connector (202); and a filter assembly is provided at the other end of each of the sampling tubes (6).

2. A chromatograph for detecting moisture in NMP according to claim 1, characterized in that: The filter assembly comprises a sealing head (602), the outer side of the sealing head (602) is provided with a threaded groove (6021) and is fixedly mounted on the end of a corresponding sampling tube (6) by means of a threaded connection, the interior of the sealing head (602) is provided with a filter layer (6022), and the end is symmetrically provided with a plurality of honeycomb holes (6023).

3. A thermal conductivity detection method of a chromatograph for detecting the moisture content of NMP according to claim 2, comprising the following steps: S1. Sample preparation: Weigh N-methylpyrrolidone (hereinafter referred to as NMP) and a diluted solution on an electronic balance, and mix the diluted solution as a solvent and NMP as a solute to obtain a standard mother solution with a concentration of C0; dilute the obtained standard mother solution step by step with the same solution as above as a solvent to obtain several groups of standard solutions with known concentrations, and the concentrations are recorded as C1, C2, C3, ..., Cn respectively; then take equal amounts of the above standard solutions with concentrations of C1, C2, C3, ..., Cn respectively into a sample bottle (4), and add equal amounts of tetrahydrofuran into the sample bottle (4) to shake and dissolve, to obtain a standard injection solution; S2, sampling: the sample bottles (4) containing the injection liquid are placed into the corresponding limiting sleeves (304) in sequence according to the marked concentration, and then the sample bottles (4) are positioned by pushing the load-bearing plate (3) into the body (1) until they pass over the clamping plate (302) and then the sample bottles (4) are lifted up by the return spring (303), and then the injection tubes in the body (1) are respectively connected to the plurality of connectors (202) on the top surface of the injection mechanism (2). When sampling, the hydraulic cylinder (501) is first operated to drive the pressure plate (5) to move downward along the limiting groove (204) through the slides (503) on both sides, so that the pressure plate (5) drives the plurality of sampling tubes (6) to move downward and insert into the corresponding sample bottles (4), thereby extracting the internal solution; When the pressure plate (5) is driven by the hydraulic cylinder (501) to move downward, it can contact the limiting plate racks (7) on both sides of the sample feeding mechanism (2), so that the corresponding limiting plate racks (7) slide down along the slide groove (203) through pressure and the sliders (701) on both sides until the limiting pressure plate (8) installed at the bottom is sleeved on the top of the corresponding sample bottle (4), and then the limiting plate rack (7) continues to move downward, so that the inner slide bars (10) on both sides of the top surface of the limiting pressure plate (8) are pressed into the corresponding limiting columns (9), and the corresponding connecting springs (1002) are squeezed to achieve the positioning of the sample bottle (4). At the same time, when the limiting plate rack (7) is pressed downward, the corresponding connecting springs (1002) are pressed downward to achieve the positioning of the sample bottle (4). When the frame (7) moves downward, the sealing ring (11) can be driven to move downward at the same time, until the conical pad (1102) fixedly installed at the bottom of the sealing ring (11) is sleeved onto the end of the corresponding sample bottle (4), and by pressing down the pressure plate (5), the bottom of the sealing ring (1102) can be in contact with and fit with the pad (1101) installed at the end of the corresponding sealing ring (11), thereby ensuring the sealing effect of the sample bottle (4). When sampling, the solution can enter the sampling tube (6) through the filter layer (6022) and the honeycomb hole (6023) at the end of the corresponding sampling tube (6), and then enter the interior of the body (1) through the elastic connecting tube (601) and the connector (202); S3, sample detection: the machine body (1) that has been started and preheated is set in thermal conductivity detection, and relevant test parameters are set; after the setting of each test parameter is completed, the chromatographic peak is collected according to the set parameters, and the numerical value is recorded and saved.

4. The thermal conductivity detection method of a chromatograph for detecting moisture in NMP according to claim 3, characterized in that: When the sample bottle (4) in S2 is placed, the inner diameter of the limiting sleeve (304) is the same as the diameter of the sample bottle (4), and before placement, it is necessary to avoid foreign matter inside the limiting sleeve (304) causing the height of the sample bottle (4) to be different.

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