Combustion gas absorption liquid generating device and combustion ion chromatograph

Abstract

A combustion gas absorption liquid generation device is provided with: a supply unit; a combustion unit for generating combustion gas by burning and decomposing the sample; and an absorption unit that causes an absorption liquid to absorb combustion gas generated in the combustion unit. The supply unit supplies the sample supplied from the sample supply unit to the combustion unit, and supplies the absorption liquid supplied from the absorption liquid supply unit to the absorption unit.

Description

Technical Field

[0001] The present invention relates to a combustion gas absorption liquid generation device and a combustion ion chromatograph equipped with the combustion gas absorption liquid generation device. Background Art

[0002] There is a combustion ion chromatograph having a combustion section, an absorption section, and a detection section. Combustion gas is generated from a sample burned in the combustion section. In the absorption section, the combustion gas generated in the combustion section is captured by an absorption liquid. The absorption liquid that has captured the combustion gas is introduced into an ion chromatograph as the detection section to detect the target substance contained in the sample. A method for determining total organic fluorine using combustion ion chromatography was studied in Non-Patent Document 1 below. In addition, a method for determining PFAS (per- and polyfluoroalkyl substances) using a combustion tube was studied in Non-Patent Document 2.

[0003] Non-Patent Document 1: "Investigation of the pollution distribution of unknown organic fluorine compounds using a total organic halogen analysis method", Hiroshi Suzuki, School of Earth Environment, Kyoto University, Report of the Research Results of the Lake Biwa - Yodo River Water Quality Conservation Agency for Fiscal Year 2016, 2017

[0004] Non-Patent Document 2: "Quantification of per- and polyfluoroalkyl substances with a modified total organic carbon analyzer and ion chromatography", AWWA Water Science, March 31, 2021 Summary of the Invention

[0005] Problems to be Solved by the Invention

[0006] Since the combustion ion chromatograph has a combustion section and an absorption section, components for supplying a sample, an absorption liquid, a cleaning liquid, etc. to these sections are required, and many components are needed. Therefore, it is desired to make the entire device smaller by reducing the number of device structures.

[0007] An object of the present invention is to reduce the number of components of the structure for supplying a sample, etc. to the combustion section and the absorption section to achieve miniaturization of the device.

[0008] Solutions to the Problems

[0009] A combustion gas absorption liquid generation device according to an aspect of the present invention includes: a supply unit; a combustion unit that generates combustion gas by burning and decomposing a sample; and an absorption unit that causes an absorption liquid to absorb the combustion gas generated in the combustion unit. The supply unit supplies the sample supplied from the sample supply unit to the combustion unit and supplies the absorption liquid supplied from the absorption liquid supply unit to the absorption unit.

[0010] In addition, the present invention is also directed to a combustion ion chromatograph.

[0011] Effects of the Invention

[0012] According to the present invention, it is possible to reduce the number of components of the structure for supplying a sample or the like to the combustion unit and the absorption unit to miniaturize the device. Description of the Drawings

[0013] Figure 1 It is an overall view showing the combustion ion chromatograph according to the present embodiment.

[0014] Figure 2 It is a diagram showing the structure of the valve included in the supply unit.

[0015] Figure 3 It is a diagram showing the absorption unit according to the modification.

[0016] Figure 4 It is a diagram showing the absorption unit according to another modification.

[0017] Figure 5 It is a diagram showing the combustion unit according to the modification. Detailed Embodiments

[0018] Next, a combustion gas absorption liquid generation device and a combustion ion chromatograph according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0019] (1) Overall Structure of Combustion Ion Chromatograph

[0020] Figure 1 It is an overall view showing the combustion ion chromatograph 1 according to the present embodiment. The combustion ion chromatograph 1 includes a supply unit 3, a combustion unit 4, an absorption unit 5, an ion chromatograph 7, and a controller 8. In addition, the combustion ion chromatograph 1 includes a sample supply unit 61, an absorption liquid tank 62, and a pure water tank 63. The combustion gas absorption liquid generation device according to the present embodiment is constituted by the supply unit 3, the combustion unit 4, the absorption unit 5, and the controller 8.

[0021] The supply unit 3 includes a valve 31 and an injection pump 32. The valve 31 is a multi-port valve. As the valve 31, for example, an eight-port multi-port valve is used. The injection pump 32 includes a cylindrical syringe 32a, a piston 32b inserted into the syringe 32a, and a drive unit 32c that moves the piston 32b in the vertical direction. As the drive unit 32c, for example, a pulse motor is used.

[0022] Figure 2 FIG. is a diagram showing the structure of the valve 31. The first port of the valve 31 is connected to the flow path 81. A sample is supplied to the supply unit 3 via the flow path 81 by the sample supply unit 61. The sample supply unit 61 is, for example, a sample bottle storing a sample. Alternatively, the sample supply unit 61 may be constituted by an automatic sampler.

[0023] The second port is connected to the flow path 82. The absorbent liquid stored in the absorbent liquid tank 62 is supplied to the supply unit 3 via the flow path 82. The third port is connected to the flow path 83. The pure water stored in the pure water tank 63 is supplied to the supply unit 3 via the flow path 83. The fourth port is connected to the flow path 84. The flow path 84 is connected to the discharge path via a valve (not shown).

[0024] The fifth port is connected to the flow path 85. The supply unit 3 supplies the sample to the combustion unit 4 via the flow path 85. The sixth port is connected to the flow path 86. The supply unit 3 supplies the absorbent liquid to the absorption unit 5 via the flow path 86. In addition, the eighth port is connected to the injection pump 32. The valve 31 can selectively connect any one of the first port to the seventh port to the injection pump 32 connected to the eighth port. For example, a rotary valve can be used as the valve 31.

[0025] Refer again to Figure 1 . The combustion unit 4 heats the sample, thereby generating gas by combustion of the sample. As the gas generated by combustion (referred to as combustion gas), for example, carbon dioxide derived from carbon, hydrogen fluoride derived from fluorine, etc. are cited. In addition, the combustion gas contains water vapor. The combustion unit 4 includes an electric furnace (heating furnace) 41 and a combustion tube 42. The combustion tube 42 is placed in a high-temperature environment such as 680 degrees by the electric furnace 41. An injection part 43 is provided at the upper end of the combustion tube 42. The injection part 43 is connected to the valve 31 via the flow path 85. The injection part 43 holds the combustion tube 42 and is provided with an injection port for injecting the sample. The lower end of the combustion tube 42 is connected to the flow path 87 via a connector 44. The combustion tube 42 is connected to the carrier gas supply path 45, and the carrier gas is supplied to the combustion tube 42 via the carrier gas supply path 45. The combustion gas generated in the combustion tube 42 is sent to the absorption unit 5 through the flow path 87.

[0026] The absorption section 5 includes an absorption liquid tube 51 that stores an absorption liquid. The ejection ports of the flow path 86 and the flow path 87 are arranged in the absorption liquid tube 51. The absorption liquid supplied from the supply section 3 is supplied to the absorption liquid tube 51 via the flow path 86. Examples of the absorption liquid include ultrapure water and an aqueous solution containing KH 2 PO 4 or H 2 O 2 and so on. The combustion gas generated in the combustion tube 42 is supplied to the absorption liquid tube 51 via the flow path 87. In addition, the ejection port of the flow path 87 is arranged near the lower end of the absorption liquid tube 51 so that the combustion gas sent out from the flow path 87 is easily captured by the absorption liquid in the absorption liquid tube 51.

[0027] In addition, the suction port of the flow path 88 is arranged in the absorption liquid tube 51. The flow path 88 is connected to the ion chromatograph 7. The absorption liquid sucked out from the absorption liquid tube 51 is transported to the ion chromatograph 7. In addition, the lower end of the absorption liquid tube 51 is connected to the flow path 89. The flow path 89 is connected to the discharge path via a valve. When draining, the valve is opened, and the absorption liquid in the absorption liquid tube 51 is discharged to the discharge path.

[0028] The ion chromatograph 7 includes a separation column and a detector. The absorption liquid generated in the combustion gas absorption liquid generation device 2 is introduced into the ion chromatograph 7. The ion chromatograph 7 detects the ions separated in the separation column in the detector. For example, fluoride ions F - , chloride ions Cl - and so on are detected in the detector. The controller 8 controls the supply section 3, the combustion section 4, the absorption section 5, and the ion chromatograph 7. In addition, the controller 8 controls the operation of the sample supply section 61.

[0029] (2) Operation of the combustion ion chromatograph

[0030] Next, the operation of the combustion ion chromatograph 1 will be described. First, the operation of supplying the absorption liquid to the absorption liquid tube 51 will be described. The valve 31 of the supply section 3 is switched so that the second port is connected to the eighth port. By driving the drive section 32c in this state, the injection pump 32 performs a suction operation, and thus the absorption liquid in the absorption liquid tank 62 is sucked into the syringe 32a. Next, the valve 31 is switched so that the sixth port is connected to the eighth port. By driving the drive section 32c in this state, the injection pump 32 performs a spraying operation, and thus the absorption liquid in the syringe 32a is supplied to the absorption liquid tube 51.

[0031] With the absorption liquid tube 51 filled with the absorption liquid, the supply of the sample is then carried out. First, the valve 31 of the supply unit 3 is switched so that the first port is connected to the eighth port. By driving the drive unit 32c in this state, the injection pump 32 performs a suction operation, thereby sucking the sample in the sample supply unit 61 into the syringe 32a. The sample is, for example, in a state where a solid or liquid target substance is dissolved in a solvent or water. As the target substance, for example, organic fluorides such as PFOA and PFOS. Next, the valve 31 is switched so that the fifth port is connected to the eighth port. By driving the drive unit 32c in this state, the injection pump 32 performs an ejection operation, thereby supplying the sample in the syringe 32a to the combustion tube 42.

[0032] In addition, before performing the above operations, the combustion tube 42 and the absorption liquid tube 51 can be cleaned as needed. In the cleaning process, the valve 31 of the supply unit 3 is switched so that the third port is connected to the eighth port. By driving the drive unit 32c in this state, the injection pump 32 performs a suction operation, thereby sucking the pure water in the pure water tank 63 into the syringe 32a. Then, in order to clean the combustion tube 42, the valve 31 is switched so that the fifth port is connected to the eighth port, thereby supplying the pure water in the syringe 32a to the combustion tube 42. In addition, in order to clean the absorption liquid tube 51, the valve 31 is switched so that the sixth port is connected to the eighth port, thereby supplying the pure water in the syringe 32a to the absorption liquid tube 51.

[0033] The sample supplied to the combustion tube 42 is heated in the electric furnace 41. As a result, in the combustion tube 42, the sample decomposes and combustion gas is generated. In addition, quartz wool, flocculent catalyst or granular catalyst, or a composite thereof is housed in the combustion tube 42 as a filler, and the sample burns during the period of staying due to these fillers. In addition, the combustion of the sample is promoted by the catalyst. The combustion gas generated in the combustion tube 42 flows downstream through the carrier gas supplied via the carrier gas supply path 45 and is supplied into the absorption liquid tube 51 via the flow path 87. The controller 8 controls the supply amount, supply speed, etc. of the carrier gas supplied via the carrier gas supply path 45. As described above, since the ejection port of the flow path 87 is disposed near the lower end of the absorption liquid tube 51, the combustion gas supplied through the flow path 87 is ejected into the absorption liquid from near the lower end of the absorption liquid tube 51. As a result, the combustion gas is efficiently captured by the absorption liquid. In addition, the water vapor contained in the combustion gas is also condensed by cooling and stored as the absorption liquid.

[0034] After sufficient time for all the specimens in the combustion tube 42 to burn and sufficient time for all the combustion gases generated in the combustion tube 42 to be sent into the absorption liquid tube 51, the analysis process for the absorption liquid is started in the ion chromatograph 7. In the absorption liquid introduced into the ion chromatograph 7, the substance to be analyzed exists in the form of ions. In the ion chromatograph 7, the ions in the absorption liquid are separated by a separation column. Then, the ions separated by the separation column are detected by a detector.

[0035] As described above, in the combustion ion chromatograph 1 of the present embodiment, the supply unit 3 performs two operations: supplying the specimen to the combustion unit 4 and supplying the absorption liquid to the absorption unit 5. Thus, the number of components of the combustion ion chromatograph 1 and the combustion gas absorption liquid generation device 2 can be reduced, and the device structure can be made compact. For example, since there is no need to separately provide the injection pump 32 and the drive unit 32c that constitute the supply unit 3, the number of components can be reduced and the cost can be lowered. In addition, since the number of drive units 32c is reduced, the maintainability is improved and the risk of failure is reduced. In addition, since the number of drive units 32c is reduced, the necessity of controlling the control timing corresponding to the state of each drive unit is reduced, and the research of the time program becomes easy in terms of developing the control program. And, in the combustion ion chromatograph 1 of the present embodiment, the supply unit 3 performs the operation of supplying the cleaning liquid to the combustion unit 4 and the absorption unit 5. Thus, the number of components of the combustion ion chromatograph 1 and the combustion gas absorption liquid generation device 2 can be reduced, and the device structure can be made compact.

[0036] (3) Variation

[0037] Next, Variations 1 to 4 of the combustion gas absorption liquid generation device and the combustion ion chromatograph according to the present embodiment will be described.

[0038] (3-1) Variation 1

[0039] Figure 3 FIG. shows the absorption unit 5A according to Variation 1. The absorption unit 5A is provided with a conductivity meter 101. The conductivity meter 101 is arranged so as to be able to measure the conductivity of the absorption liquid inside the absorption liquid tube 51. The conductivity measured by the conductivity meter 101 is output to the controller 8. The controller 8 can obtain the amount of ions in the absorption liquid based on the conductivity of the absorption liquid. Thus, the controller 8 can estimate the capture amount of the combustion gas by the absorption liquid based on the amount of ions.

[0040] When the controller 8 starts the analysis using combustion ion chromatography, it monitors the conductivity of the absorption liquid and calculates its rate of change. When a prescribed amount of the sample is supplied to the combustion unit 4, combustion gas starts to be generated. Then, when the combustion gas starts to be captured by the absorption liquid, the conductivity of the absorption liquid starts to rise. During the period when the combustion gas is continuously supplied to the absorption liquid, the conductivity of the absorption liquid continuously varies. However, as the combustion (decomposition of the sample) in the combustion tube 42 progresses, the remaining amount of the sample in the combustion tube 42 gradually decreases, so the supply amount of the combustion gas to the absorption liquid also gradually decreases. The controller 8 continuously monitors the conductivity of the absorption liquid and calculates the conductivity, and compares the rate of change of the conductivity with a prescribed threshold value. Moreover, the controller 8 determines that the combustion of the sample in the combustion tube 42 is completed and the absorption of the combustion gas by the absorption liquid is completed at the time point when the rate of change of the conductivity is lower than the prescribed threshold value.

[0041] When the controller 8 determines that the absorption of the combustion gas by the absorption liquid is completed, it issues an instruction to start the analysis process to the ion chromatograph 7. In response to this instruction, the analysis process of the sample starts in the ion chromatograph 7. According to Modification Example 1, it is possible to obtain the time when the absorption of the combustion gas by the absorption liquid is completed. That is, the controller 8 can determine the end of the processes in the combustion unit 4 and the absorption unit 5. The time until the absorption of the combustion gas by the absorption liquid is completed varies depending on the type of the target substance contained in the sample, the processing conditions in the combustion unit 4, the device structure, etc. Conventionally, a fixed-length time is set to ensure a time sufficient for the absorption of the combustion gas by the absorption liquid to be reliably completed. Therefore, even in the case where the processing time is short, a long processing time is uniformly required. According to Modification Example 1, it is possible to eliminate the useless waiting time to achieve the high efficiency of the process. According to Modification Example 1, it is possible to automatically end the process in the absorption unit 5. In addition, in the case where the concentration of the target substance contained in the sample is low, the sample is easily decomposed by combustion, etc., the absorption process can be ended in a short time, so the productivity is improved.

[0042] (3-2) Modification Example 2

[0043] Figure 4 FIG. is a view showing the absorption unit 5B according to Modification Example 2. The absorption unit 5B includes a spiral member 102. The spiral member 102 is disposed in the absorption liquid tube 51 such that its central axis coincides with the central axis of the absorption liquid tube 51. Thus, when the absorption liquid is supplied to the absorption liquid tube 51, the spiral member 102 is also disposed in the absorption liquid.

[0044] In Modification 2, the flow path 87 is inserted into a space extending in the vertical direction inside the spiral member 102. The ejection port of the flow path 87 is disposed at a position below the lower end of the spiral member 102. With such a configuration, the combustion gas ejected from the ejection port of the flow path 87 rises from the lower end portion of the spiral member 102 toward the upper end portion. At this time, due to the shape of the spiral member 102, the combustion gas does not rise straight, but rises in a spiral shape. Thereby, the combustion gas can be efficiently captured by the absorption liquid. The contact time / contact distance between the combustion gas and the absorption liquid can be made longer than in the case of rising straight, and thereby the recovery rate of the absorption liquid recovery can be improved.

[0045] In the combustion ion chromatograph 1, in order to obtain a correct analysis result, it is desirable that all of the sample supplied by the supply unit 3 is reliably absorbed by the absorption liquid. Conventionally, the absorption liquid tube 51 is filled with a sufficient amount of absorption liquid so that the combustion gas is sufficiently absorbed by the absorption liquid. However, if the amount of the absorption liquid is large, the concentration of the target substance is diluted accordingly, resulting in a decrease in analysis sensitivity. Since the absorption unit 5B according to Modification 2 includes the spiral member 102, it is possible to sufficiently capture the combustion gas by the absorption liquid while suppressing an increase in the amount of the absorption liquid. In addition, with respect to the lower end portion of the spiral member 102, the member is disposed inclined with respect to the horizontal direction, so that the ejected absorption liquid can rise in a spiral shape without stagnation.

[0046] When the combustion ion chromatograph 1 according to Modification 2 is used in halogen analysis, it is desirable to use a material that does not contain halogen as the spiral member 102. For example, as the spiral member 102, by using raw materials such as glass and polyether ether ketone (PEEK), it is possible to prevent contamination of the measurement result. For example, it is possible to prevent contamination by fluoride ions or the like that may be generated from the spiral member 102 itself. As the spiral member 102, a linear member may be processed into a spiral shape. Alternatively, the spiral member 102 may be formed by winding a long sheet member into a cylindrical shape and stretching it in the axial direction.

[0047] (3-3) Modification 3

[0048] Figure 5 FIG. is a view showing the combustion tube 42A according to Modification 3. The combustion tube 42A is formed with a reduced portion 422 in the middle portion in the vertical direction. The cross-sectional area of the reduced portion 422 in the horizontal direction (when the long side direction of the combustion tube 42A is the vertical direction) is smaller than that of the upper portion 421 and the lower portion 423 of the reduced portion 422. That is, the cross-sectional area of the middle portion in the long side direction of the combustion tube 42A is smaller than the cross-sectional area of the portions other than the middle portion.

[0049] Moreover, as Figure 5As shown, in the combustion tube 42A, a fibrous member 425 such as quartz wool or flocculent catalyst is filled in the reduced portion 422. By adopting such a structure, it is possible to prevent the fibrous member 425 from moving to the lower end of the combustion tube 42A due to the introduction of the sample.

[0050] In the combustion ion chromatograph 1, the analysis sensitivity depends on the amount of the sample supplied to the combustion unit 4. When the target substance is at a low concentration, for example, it is necessary to supply a sample in an amount of about 1000 μL to the combustion unit 4. When the amount of the sample is large like this, the fibrous member 425 as the filler in the combustion tube 42A will be gradually pushed downward toward the combustion tube 42A. According to Modification 3, since the reduced portion 422 is formed, the movement of the fibrous member 425 can be suppressed.

[0051] The combustion tube 42 is placed in a high-temperature environment by heating with the electric furnace 41. However, since the upper and lower end portions of the combustion tube 42 are connected to the flow path and are open, the temperature of the upper and lower end portions is lower than that of the central portion. That is, a temperature gradient is generated in the combustion tube 42 in the vertical direction (long side direction). In Modification 3, the reduced portion 422 is provided in the middle portion in the vertical direction (for example, the central portion in the vertical direction), so that the fibrous member 425 can be retained in the middle portion in the vertical direction, and the sample can be processed in the high-temperature region. Thereby, the combustion treatment in the combustion unit 4 can proceed efficiently.

[0052] (3-4) Modification 4

[0053] In combustion ion chromatography, when analyzing an organic fluorine compound, due to its flame retardancy or difficult decomposability, the analyte sometimes remains in the flow path. Therefore, pure water is injected into the combustion unit 4 after the combustion treatment separately from the sample to improve the recovery rate of the analyte in the absorption unit 5. Then, an operation of also taking the injected pure water into the absorption liquid is performed to wash the residual substances. This operation is the same as the cleaning operation, but the injected pure water itself is also recovered as the absorption liquid.

[0054] The difference between the supply unit 3 in Modification Example 4 and the conventional structure is that the sample is supplied to the combustion unit 4 at a rate of 30 seconds / 1 mL to 50 seconds / 1 mL. In the conventional combustion ion chromatography method, the sample is supplied to the combustion unit in a very short time of less than 1 second. In Modification Example 4, the sample is supplied at a very slow rate of 30 seconds / 1 mL to 50 seconds / 1 mL, so that the increase in air pressure in the flow path 85 and the combustion unit 4 can be suppressed to a low level. As a result, no load is applied to the components in the flow path 85 and the combustion unit 4, and thus a large amount of sample can be supplied in one process. For example, conventionally, about 0.1 mL of sample could be supplied each time, but if the method of Modification Example 4 is used, about 0.5 mL of sample can be supplied each time. In addition, conventionally, about 0.1 mL of pure water was supplied each time to rinse the remaining analyte, but if the method of Modification Example 4 is used, about 1.5 mL of pure water can be supplied each time.

[0055] For example, conventionally, after supplying the sample 10 times in a manner of supplying 0.1 mL of sample each time, pure water was supplied 30 times in a manner of supplying 0.1 mL of pure water each time, thereby supplying 1 mL of sample to the combustion unit and collecting all these samples into the absorption unit using pure water. In contrast, according to this Modification Example 4, by supplying the sample 2 times in a manner of supplying 0.5 mL of sample each time and then supplying pure water 2 times in a manner of supplying 1.5 mL of pure water each time, the same amount of sample can be collected into the absorption unit 5.

[0056] To supply 0.5 mL of sample to the combustion unit 4, if the rate is 30 seconds / 1 mL to 50 seconds / 1 mL, it takes about 15 seconds to 25 seconds. Therefore, by the method of Modification Example 4, the increase in the time required for each supply of sample and pure water is about 15 seconds to 25 seconds. In contrast, since the sample and pure water are supplied in multiple times, it takes about 3 minutes to 5 minutes each time including the recovery time for the temperature drop of the electric furnace. Therefore, although the supply time for each time becomes longer, the number of repeated supplies becomes about 1 / 10, so that a significant reduction in the processing time can be achieved.

[0057] In this way, according to Modification Example 4, the supply unit 3 supplies the sample to the combustion unit 4 at a rate of 30 seconds / 1 mL to 50 seconds / 1 mL, so that the amount of sample or pure water that can be supplied in one operation can be increased without applying a load to the components of the device. In addition, after the supply unit 3 supplies the sample to the combustion unit 4 1 to 5 times (2 times in the above example), the cleaning liquid is supplied to the combustion unit 4 1 to 5 times (2 times in the above example), so that a significant reduction in the processing time can be achieved.

[0058] (4) Other Modification Examples

[0059] The combustion gas absorption liquid generation device 2 of the above-described embodiment has a structure for separately supplying pure water for cleaning from the absorption liquid. Depending on the properties of the target substance, pure water can also be used as the absorption liquid. In this case, the structure for supplying the absorption liquid and pure water can be made common.

[0060] (5) Corresponding relationship between each component of the claims and each element of the embodiment

[0061] Next, examples of the corresponding relationship between each component of the claims and each element of the embodiment will be described, but the present invention is not limited to the following examples. In the above-described embodiment, the absorption liquid tank 62 is an example of the absorption liquid supply unit, and the pure water tank 63 is an example of the cleaning liquid supply unit. In addition, in the above-described embodiment, the flow path 87 is an example of the combustion gas flow path.

[0062] As each component of the claims, various elements having the structure or function described in the claims can also be used.

[0063] (6) Mode

[0064] Those skilled in the art should understand that the above-described multiple exemplary embodiments are specific examples of the following modes.

[0065] (First item)

[0066] A combustion gas absorption liquid generation device according to one mode includes:

[0067] A supply unit;

[0068] A combustion unit that generates combustion gas by burning and decomposing a sample; and

[0069] An absorption unit that causes an absorption liquid to absorb the combustion gas generated in the combustion unit,

[0070] wherein the supply unit supplies the sample supplied from the sample supply unit to the combustion unit and supplies the absorption liquid supplied from the absorption liquid supply unit to the absorption unit.

[0071] The number of components of the structure for supplying the sample and the like to the combustion unit and the absorption unit can be reduced to achieve miniaturization of the device.

[0072] (Second item)

[0073] In the combustion gas absorption liquid generation device described in the first item, it may be that

[0074] the supply unit includes:

[0075] An injection pump; and

[0076] A multi-port valve, which is connected to the sample supply unit, the absorbent liquid supply unit and the syringe pump,

[0077] Wherein, when the sample is supplied from the sample supply unit, the multi-port valve is switched to connect between the sample supply unit and the syringe pump; when the absorbent liquid is supplied from the absorbent liquid supply unit, the multi-port valve is switched to connect between the absorbent liquid supply unit and the syringe pump.

[0078] The syringe pump for supplying the sample and the absorbent liquid and its driving part can be shared.

[0079] (Item 3)

[0080] In the combustion gas absorbent liquid generating device described in the second item, it may also be that

[0081] The multi-port valve is also connected to the combustion part and the absorption part. When supplying the sample to the combustion part, the multi-port valve is switched to connect between the syringe pump and the combustion part; when supplying the absorbent liquid to the absorption part, the multi-port valve is switched to connect between the syringe pump and the absorption part.

[0082] The syringe pump for supplying the sample and the absorbent liquid and its driving part can be shared.

[0083] (Item 4)

[0084] In the combustion gas absorbent liquid generating device described in the second item, it may also be that

[0085] The multi-port valve is also connected to a cleaning liquid supply unit, and the multi-port valve can be switched to connect between the cleaning liquid supply unit and the syringe pump.

[0086] The syringe pump for supplying the sample and the absorbent liquid and its driving part can also be shared as a component for supplying the cleaning liquid.

[0087] (Item 5)

[0088] In the combustion gas absorbent liquid generating device described in the first item, it may also be that it further includes:

[0089] A conductivity meter for measuring the conductivity of the absorbent liquid in the absorption part; and

[0090] A controller for determining the completion of the processes in the combustion part and the absorption part based on the conductivity measured by the conductivity meter.

[0091] By measuring the amount of ions in the absorbent liquid, the progress state of the processes in the combustion part and the absorption part can be grasped.

[0092] (Item 6)

[0093] In the combustion gas absorption liquid generation device described in Item 5, it may also be that

[0094] when the rate of change of the conductivity is lower than a specified threshold value, the controller determines that the processing in the combustion unit and the absorption unit is completed.

[0095] It is possible to grasp the progress state of the processing in the combustion unit and the absorption unit based on the rate of change of the ion amount.

[0096] (Item 7)

[0097] In the combustion gas absorption liquid generation device described in Item 1, it may also be that

[0098] The absorption unit includes:

[0099] a spiral member that extends in the vertical direction in the absorption liquid pipe storing the absorption liquid; and

[0100] a combustion gas flow path that supplies the combustion gas generated in the combustion unit into the absorption liquid pipe below the spiral member.

[0101] It is possible to enable the absorption liquid to efficiently capture the combustion gas.

[0102] (Item 8)

[0103] In the combustion gas absorption liquid generation device described in Item 1, it may also be that

[0104] the combustion unit includes a combustion tube that is disposed in a heating furnace and is used for supplying the specimen,

[0105] the cross-sectional area of the middle part in the longitudinal direction of the combustion tube is smaller than the cross-sectional area of the part other than the middle part.

[0106] When quartz wool, a catalyst, etc. are filled, it is possible to suppress the movement of these members.

[0107] (Item 9)

[0108] In the combustion gas absorption liquid generation device described in Item 8, it may also be that

[0109] quartz wool, a catalyst, or a composite thereof is filled in the middle part.

[0110] It is possible to enable the specimen to burn efficiently in the middle part of the combustion tube.

[0111] (Item 10)

[0112] In the combustion gas absorption liquid generation device according to the first item, it may also be that

[0113] The supply unit supplies the sample to the combustion unit at a rate of 30 seconds / 1 mL to 50 seconds / 1 mL.

[0114] It is possible to suppress the load applied to components such as the combustion unit.

[0115] (Eleventh item)

[0116] In the combustion gas absorption liquid generation device according to the tenth item, it may also be that

[0117] After the supply unit supplies the sample to the combustion unit 1 to 5 times, it supplies the cleaning liquid to the combustion unit 1 to 5 times.

[0118] It is possible to reduce the number of repetitions of supplying the sample to the combustion unit.

[0119] (Twelfth item)

[0120] The combustion ion chromatograph according to another aspect includes the combustion gas absorption liquid generation device according to any one of the first to eleventh items.

Claims

1. A combustion gas absorption liquid generation device, comprising: A supply unit; A combustion unit that generates combustion gas by burning and decomposing a sample; and An absorption unit that allows an absorption liquid to absorb the combustion gas generated in the combustion unit, wherein The supply unit supplies the sample supplied from the sample supply unit to the combustion unit, and supplies the absorption liquid supplied from the absorption liquid supply unit to the absorption unit.

2. The combustion gas absorption liquid generation device according to claim 1, wherein The supply unit includes: An injection pump; and A multi-port valve connected to the sample supply unit, the absorption liquid supply unit, and the injection pump, wherein when supplying the sample from the sample supply unit, the multi-port valve is switched to connect between the sample supply unit and the injection pump, and when supplying the absorption liquid from the absorption liquid supply unit, the multi-port valve is switched to connect between the absorption liquid supply unit and the injection pump.

3. The combustion gas absorption liquid generation device according to claim 2, wherein The multi-port valve is also connected to the combustion unit and the absorption unit. When supplying the sample to the combustion unit, the multi-port valve is switched to connect between the injection pump and the combustion unit, and when supplying the absorption liquid to the absorption unit, the multi-port valve is switched to connect between the injection pump and the absorption unit.

4. The combustion gas absorption liquid generation device according to claim 2, wherein The multi-port valve is also connected to a cleaning liquid supply unit, and the multi-port valve can be switched to connect between the cleaning liquid supply unit and the injection pump.

5. The combustion gas absorption liquid generation device according to claim 1, wherein It further includes: A conductivity meter that measures the conductivity of the absorption liquid in the absorption unit; and A controller that determines the completion of the processing in the combustion unit and the absorption unit based on the conductivity measured by the conductivity meter.

6. The combustion gas absorption liquid generation device according to claim 5, wherein The controller determines that the processing in the combustion unit and the absorption unit is completed when the rate of change of the conductivity is lower than a specified threshold value.

7. The combustion gas absorption liquid generation device according to claim 1, wherein The absorption unit includes: A spiral member that extends in the vertical direction in an absorption liquid tube storing the absorption liquid; and A combustion gas flow path that supplies the combustion gas generated in the combustion unit into the absorption liquid tube below the spiral member.

8. The combustion gas absorption liquid generation device according to claim 1, wherein The combustion unit includes a combustion tube disposed in a heating furnace for supplying the sample, The cross-sectional area of the middle part in the long side direction of the combustion tube is smaller than the cross-sectional area of the parts other than the middle part.

9. The combustion gas absorption liquid generation device according to claim 8, wherein Quartz wool, a catalyst, or a composite thereof is filled in the middle part.

10. The combustion gas absorption liquid generation device according to claim 1, wherein The supply unit supplies the sample to the combustion unit at a rate of 30 seconds / 1 mL to 50 seconds / 1 mL.

11. The combustion gas absorption liquid generation device according to claim 10, wherein, after the supply unit supplies the sample to the combustion unit 1 to 5 times, the supply unit supplies the cleaning liquid to the combustion unit 1 to 5 times.

12. A combustion ion chromatograph, comprising the combustion gas absorption liquid generation device according to any one of claims 1 to 11.

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