JP7286151B2 - Thermal desorption analyzer and thermal desorption analysis method - Google Patents

Description

Application of Article 30, Paragraph 2 of the Patent Act (1) December 5, 2018, Abstracts of the 45th Annual Meeting of the Carbon Society of Japan, p.220, The Carbon Society of Japan (2) December 7, 2018, Article 45th Annual Meeting of the Carbon Society of Japan, National University Corporation Nagoya Institute of Technology (3) June 27, 2019, website: http://carbon2019. org/wp-content/uploads/2019/07/365-ishii. pdf (4) July 15, 2019, Carbon 2019, Lexington (USA)

The present invention relates to a thermal desorption spectrometer and a thermal desorption spectrometry method.

In Patent Document 1, the total amount of the carbon edge surface of the carbon catalyst is calculated from the quantitative results of the desorption gas of the carbon catalyst obtained using a thermal desorption spectrometer capable of increasing the temperature up to 1600 ° C. It is described that the average carbon network plane size L was calculated from. Non-Patent Document 1 and Non-Patent Document 2 describe a thermal desorption spectrometer capable of raising the temperature up to 1800°C.

WO2017/209244

Takafumi Ishii et al. A quantitative analysis of carbon edge sites and an estimation of graphene sheet size in high-temperature treated, non-porous carbons. Carbon 2014; 80: 135-145 Takafumi Ishii et al. Analysis of trace amounts of edge sites in natural graphite, synthetic graphite and high-temperature treated coke for the understanding of their carbon structures molecular. Carbon 2017; 125: 146-155

On the other hand, conventionally, when it is necessary to mix a solid sample with a liquid before starting analysis, the solid sample is first dried outside the thermal desorption spectrometer, and then the dried solid sample is subjected to the thermal desorption. It was necessary to install it in a desorption analyzer and then perform thermal desorption analysis.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a thermal desorption spectrometer and a thermal desorption spectrometry method that can easily analyze a solid sample mixed with a liquid. one.

A thermal desorption spectrometer according to one embodiment of the present invention for solving the above problems comprises a sample chamber having an internal space that can be depressurized, a heater for heating a solid sample in the sample chamber, and the sample chamber. a detector for detecting desorption gas evolved from the solid sample heated within, wherein the sample chamber is a sample container for containing a mixture of the solid sample and liquid within the interior space; and a heat transfer member having a connecting portion heat-transferably connected to the sample container and a cooled portion cooled to freeze the mixture in the sample container. Device. ADVANTAGE OF THE INVENTION According to this invention, the thermal desorption spectrometer which can analyze the solid sample mixed with the liquid simply is provided.

Further, the cooled portion of the heat transfer member may be formed to protrude from the internal space of the sample chamber. Further, the heat transfer member may be a rod-shaped member having one end as the connecting portion and the other end as the cooled portion. Moreover, the heat transfer member may include a carbon member having the connecting portion. Moreover, the heat transfer member may include a metal member having the portion to be cooled.

Further, the sample chamber includes a first portion that accommodates the sample container and a second portion that accommodates the heat transfer member, and the first portion and the second portion are separably connected. good too. Also, the heater may be a heater that heats the solid sample to 500° C. or higher. Also, the heater may be a high-frequency induction heater. Also, the sample chamber may further include a cooler.

A thermal desorption spectroscopy method according to an embodiment of the present invention for solving the above problems is to analyze a solid sample by a thermal desorption method using any of the thermal desorption spectrometers described above. It is a thermal desorption analysis method. ADVANTAGE OF THE INVENTION According to this invention, the thermal desorption spectroscopy method which can analyze the solid sample mixed with the liquid simply is provided.

The method includes: placing a mixture of a solid sample and a liquid in the sample container in the sample chamber; cooling the cooled portion of the heat transfer member connected to the sample container; depressurizing the interior space of the sample chamber to dry the frozen mixture in the sample container; and removing the mixture left in the sample container by drying the mixture. The method may include analyzing the solid sample by a thermal desorption method while being heated by the heater.

ADVANTAGE OF THE INVENTION According to this invention, the thermal desorption spectroscopy apparatus and the thermal desorption spectroscopy method which can analyze the solid sample mixed with the liquid simply are provided.

1 is an explanatory diagram schematically showing the main configuration of an example of a thermal desorption spectrometer according to an embodiment of the present invention; FIG. FIG. 2 is an explanatory diagram showing a state in which a mixture of a solid sample and a liquid is placed in a sample chamber included in the thermal desorption spectrometer shown in FIG. 1; 2B is an explanatory view schematically showing how the heat transfer member is cooled in the sample chamber shown in FIG. 2A; FIG. BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows the main processes included in an example of the thermal desorption spectrometry method which concerns on one Embodiment of this invention. FIG. 4 is an explanatory diagram showing an example of a temperature programmed desorption spectrum obtained for a carbon material not subjected to hydrogen-deuterium replacement treatment in an example according to one embodiment of the present invention. FIG. 6 is an explanatory diagram showing another example of a temperature programmed desorption spectrum obtained for a carbon material not subjected to hydrogen-deuterium replacement treatment in an example according to one embodiment of the present invention. FIG. 2 is an explanatory diagram showing an example of a temperature programmed desorption spectrum obtained for a carbon material subjected to a hydrogen-deuterium substitution treatment in an example according to one embodiment of the present invention; FIG. 10 is an explanatory diagram showing another example of a temperature programmed desorption spectrum obtained for a carbon material subjected to hydrogen-deuterium substitution treatment in an example according to one embodiment of the present invention.

An embodiment of the present invention will be described below. Note that the present invention is not limited to the example shown in this embodiment.

First, a thermal desorption spectrometer (hereinafter referred to as "this device") according to this embodiment will be described. FIG. 1 schematically shows the main configuration of an example of the device 1. As shown in FIG. FIG. 2A shows a state in which a mixture M of a solid sample S and a liquid L is placed in the sample chamber 10 included in the apparatus 1 shown in FIG. FIG. 2B schematically shows how the heat transfer member 50 is cooled in the sample chamber 10 shown in FIG. 2A.

As shown in FIG. 1, the apparatus 1 includes a sample chamber 10 having an internal space 11 that can be depressurized, a heater 20 that heats a solid sample S in the sample chamber 10, and a A detector 30 for detecting desorption gas generated from the solid sample S is included.

The sample chamber 10 of the apparatus 1 has a sample container 40 for containing the mixture M of the solid sample S and the liquid L in the internal space 11, and is connected to the sample container 40 so as to be heat-transferable. a heat transfer member 50 having a connecting portion 50a and a cooled portion 50b that is cooled to freeze the mixture M in the sample vessel 40;

The sample chamber 10 of the device 1 has an internal space 11 that can be depressurized and an outer wall 12 that surrounds the internal space 11 . A sample container 40 and a heat transfer member 50 are arranged in the internal space 11 of the sample chamber 10 .

As shown in FIG. 2A, the sample chamber 10 includes a first portion 10a that houses the sample container 40 and a second portion 10b that houses the heat transfer member 50. The first portion 10a and the second portion 10b are It may be connected in a separable manner. In this case, the mixture M can be easily placed inside the sample chamber 10 .

Specifically, in the example shown in FIG. 2A , the first portion 10 a of the sample chamber 10 constitutes the upper portion of the sample chamber 10 in the vertical direction and accommodates the sample container 40 . The second portion 10 b of the sample chamber 10 constitutes the lower portion of the sample chamber 10 in the vertical direction and accommodates the heat transfer member 50 . The lower end of the first portion 10a and the upper end of the second portion 10b are separably connected.

More specifically, the first portion 10 a has an outer wall 12 a that is part of the outer wall 12 of the sample chamber 10 and surrounds the sample container 40 . The second portion 10 b also has an outer wall 12 b that is another part of the outer wall 12 of the sample chamber 10 and surrounds the heat transfer member 50 . The lower end of the outer wall 12a of the first portion 10a and the upper end of the outer wall 12b of the second portion 10b are separably connected.

In the example shown in FIG. 2A, the first portion 10a of the sample chamber 10 accommodates a portion of the heat transfer member 50 (a portion on the upper side in the vertical direction), and the second portion 10b accommodates the heat transfer member 50 as well as the heat transfer member 50. (a part on the lower side in the vertical direction) is accommodated.

An O-ring 13 is arranged at the connecting portion between the outer wall 12a of the first portion 10a and the outer wall 12b of the second portion 10b to ensure the airtightness of the internal space 11. As shown in FIG. That is, a sealed internal space 11 is formed in the sample chamber 10 by connecting the first portion 10a and the second portion 10b of the sample chamber 10 in close contact.

The outer wall 12a of the first portion 10a of the sample chamber 10 and the outer wall 12b of the second portion 10b may be made of the same material or may be made of different materials. The material constituting the outer wall 12a of the first portion 10a is not particularly limited as long as it is a material having insulating properties and heat resistance suitable for analysis by the thermal desorption method, but the material should be transparent. is preferred.

Here, the apparatus 1 may further include a thermometer 60 that measures the temperature of the solid sample S inside the sample container 40 . In this case, the apparatus 1 may further include a control device (not shown) that adjusts the heating intensity of the solid sample S by the heater 20 based on the measurement result of the temperature of the solid sample S by the thermometer 60. good.

Then, the thermometer 60 is a radiation thermometer (for example, an infrared radiation thermometer or a visible In the case of a light radiation thermometer, preferably an infrared radiation thermometer), at least a portion of the outer wall 12 of the sample chamber 10 that is arranged between the thermometer 60 and the sample container 40 (especially the thermometer 60 and , and the opening 41a of the concave portion 41 of the sample container 40 facing the thermometer 60) are made of a material that transmits infrared rays and/or visible rays emitted from the solid sample S. be done.

Specifically, the outer wall 12a of the first portion 10a of the sample chamber 10 is preferably made of quartz. That is, for example, the entire outer wall 12a of the first portion 10a of the sample chamber 10 may be made of quartz.

The material constituting the outer wall 12b of the second portion 10b is not particularly limited as long as it has properties suitable for analysis by the thermal desorption method. good.

The metal forming the outer wall 12b of the second portion 10b is, for example, preferably one or more metals selected from the group consisting of stainless steel, aluminum, titanium, and copper. and one or more selected from the group consisting of SUS316L). That is, for example, the entire outer wall 12b of the second portion 10b of the sample chamber 10 may be made of metal (eg, stainless steel).

The sample container 40 holds the mixture M of the solid sample S and the liquid L when the mixture M is freeze-dried within the internal space 11 of the sample chamber 10 . Further, the sample container 40 holds the solid sample S after freeze-drying when the freeze-dried solid sample S is analyzed by the thermal desorption method.

The sample container 40 has a recess 41 capable of containing the mixture M containing the liquid L. The volume of the recess 41 may be, for example, 0.01 mL or more and 1.00 mL or less, 0.03 mL or more and 0.30 mL or less, or 0.05 mL or more and 0.15 mL or less. It can be a certain thing.

The recess 41 of the sample container 40 has an opening 41a. The recess 41 communicates with the internal space 11 of the sample chamber 10 via the opening 41a. Therefore, in the drying of the frozen mixture M, which will be described later, the gas originating from the sublimation of the frozen material of the liquid L, which is generated from the frozen mixture M, is released from the concave portion 41 of the sample container 40 through the opening 41a. It is discharged into the decompressed internal space 11 of the sample chamber 10 .

The material constituting the sample container 40 is, for example, resistant to the freezing temperature of the mixture M and the heating temperature during thermal desorption analysis, the amount of gas generated at the heating temperature is small, and at the heating temperature It satisfies the condition that it does not cause a chemical reaction with the solid sample S.

When the solid sample S in the sample container 40 is heated by high-frequency induction heating, the sample container 40 is made of a conductive material whose temperature rises due to the high-frequency induction heating. Specifically, the sample container 40 is preferably made of graphite or vitreous carbon, for example.

Moreover, it is particularly preferable that the sample container 40 has a surface coated with a dense carbon film. A dense carbon film is formed by chemical vapor deposition, for example. In order to repair structural defects in the dense carbon film, it is preferable to heat-treat the dense carbon film of the sample container 40 at a high temperature (for example, 1900° C. or higher) prior to thermal desorption analysis.

A heat transfer member 50 is provided for freezing the mixture M in the sample container 40 . The heat transfer member 50 has a connection portion 50a that is heat transferably connected to the sample container 40, and a cooled portion 50b that is cooled to freeze the mixture M in the sample container 40.

The connection part 50a is a part of the heat transfer member 50 physically connected to the sample container 40, and the cooled part 50b is the heat transfer member that is cooled when the mixture M in the sample container 40 is frozen. Another part of the member 50 .

The cooled portion 50 b of the heat transfer member 50 may be formed to protrude from the internal space 11 of the sample chamber 10 . In this case, the cooled portion 50b of the heat transfer member 50 can be effectively cooled.

Specifically, the cooled portion 50b of the heat transfer member 50 may be formed to protrude downward in the vertical direction from the internal space 11 of the sample chamber 10, as shown in FIG. 2A.

In this case, as shown in FIG. 2B, the cooled portion 50b of the transmission member 50 is simply cooled by immersing the cooled portion 50b in the liquid coolant R (eg, liquid nitrogen) in the container C. be able to.

Also, the cooled portion 50b of the heat transfer member 50 may be covered with a portion of the outer wall 12 (the outer wall 12c) of the sample chamber 10, as shown in FIG. 2A. In this case, the cooled portion 50b of the heat transfer member 50 and the outer wall 12c of the sample chamber 10 covering the cooled portion 50b are preferably in heat-transferable contact, particularly preferably in close contact. .

Since the cooled portion 50b of the heat transfer member 50 is covered with the outer wall 12c of the sample chamber 10, the cooled portion 50b can be protruded and high vacuum can be easily achieved in the sample chamber 10. can.

Note that the cooled portion 50 b of the heat transfer member 50 may be exposed outside the sample chamber 10 without being covered by the outer wall 12 c of the sample chamber 10 . In this case, the cooled portion 50b of the heat transfer member 50 can be effectively cooled.

The heat transfer member 50 may be a rod-shaped member having one end as the connecting portion 50a and the other end as the cooled portion 50b.

Specifically, as shown in FIG. 2A, the heat transfer member 50 may be formed as a rod-shaped member extending vertically in the vertical direction. In this case, for example, the upper end portion of the heat transfer member 50 constitutes the connection portion 50a, and the lower end portion constitutes the cooled portion 50b.

The material constituting the heat transfer member 50 has, for example, a thermal conductivity of 0.2 W/(mK) or more at 25° C., and is resistant to the freezing temperature of the mixture M and the heating temperature during thermal desorption analysis. , the amount of gas generated at the heating temperature is small, and no chemical reaction with the solid sample S occurs at the heating temperature.

Specifically, the heat transfer member 50 may include a carbon member 51 having a connecting portion 50a. In this case, a portion of the carbon member 51 of the heat transfer member 50 is heat-transferably connected to the sample container 40 as the connecting portion 50a.

The carbon member 51 may be, for example, a rod-shaped member. In this case, the carbon member 51 may be a solid rod-shaped member or a hollow rod-shaped member. The carbon member 51 is preferably made of graphite or vitreous carbon, and particularly preferably made of graphite.

The heat transfer member 50 may include a metal member 52 having a cooled portion 50b. In this case, a portion of the metal member 51 of the heat transfer member 50 is cooled to freeze the mixture M in the sample container 40 as the cooled portion 50b.

The metal member 52 may be, for example, a rod-shaped member. In this case, the metal member 52 may be a solid rod-shaped member or a hollow rod-shaped member. The metal member 52 is preferably made of, for example, one or more metals selected from the group consisting of copper, aluminum, titanium, silver, gold, and platinum, and is selected from the group consisting of copper, aluminum, and titanium. It is more preferably made of one or more metals, and particularly preferably made of copper.

The heat transfer member 50 may include a carbon member 51 and a metal member 52 . That is, the heat transfer member 50 may be composed of a carbon member 51 and a metal member 52 as shown in FIG. 2A. When the carbon member 51 and the metal member 52 are rod-shaped members, one end (for example, the upper end in the vertical direction) of the carbon member 51 is heat-transferable with the sample container 40 as the connecting portion 50a. The other end of the carbon member 51 (for example, the lower end in the vertical direction) and the one end of the metal member 52 (for example, the upper end in the vertical direction) can be heat-transferred. , and the other end (for example, the vertically lower end) of the metal member 52 is cooled to freeze the mixture M in the sample container 40 as the cooled portion 50b.

The heater 20 heats the solid sample S accommodated in the sample container 40 within the sample chamber 10 during analysis by the thermal desorption method. The heater 20 may be, for example, a heater that heats the solid sample S to 500° C. or higher. In this case, the temperature at which the heater 20 heats the solid sample S may be, for example, 600° C. or higher, 700° C. or higher, 800° C. or higher, or 900° C. or higher. It is also possible to be Furthermore, the temperature at which the heater 20 heats the solid sample S may be, for example, 1000° C. or higher, 1100° C. or higher, 1200° C. or higher, or 1300° C. or higher. It may be 1400° C. or higher, 1500° C. or higher, or 1600° C. or higher. Specifically, for example, when the solid sample S contains a carbon material and the hydrogen gas desorbed from the carbon material is measured by the thermal desorption method, the heater 20 heats the solid sample S at 1400° C. or higher. A heater is preferred.

The heater 20 may be, for example, one or more selected from the group consisting of a high-frequency induction heater, an infrared heater, and a microwave heater, and is particularly preferably a high-frequency induction heater.

The heater 20, which is a high-frequency induction heating heater, includes a high-frequency induction heating coil 21, as shown in FIG. 2A. A coil 21 is arranged outside the sample chamber 10 . That is, in the example shown in FIG. 2A, the coil 21 is arranged along the outer circumference of the sample chamber 10 so as to surround the sample container 40 .

The high-frequency induction heating coil 21 is made of metal. The metal forming the coil 21 is not particularly limited as long as it is suitable for high-frequency induction heating, but the coil 21 is preferably made of copper or aluminum, and particularly preferably made of copper.

Sample chamber 10 may further include cooler 70 . The cooler 70 is not particularly limited as long as it cools the sample chamber 10 (specifically, the outer wall 12 of the sample chamber 10), and is preferably a water-cooled and/or air-cooled cooler. is particularly preferred.

In the example shown in FIG. 2A, the device 1 includes a water-cooled cooler 70 . The cooler 70 has a cooling channel 71 through which a coolant (for example, cooling water) flows. This cooling channel 71 is formed along the outer circumference of the outer wall 12 of the sample chamber 10 .

A cooler 70 is arranged to cool a portion of the outer wall 12 of the sample chamber 10 surrounding the sample container 40 . That is, when the sample chamber 10 has the first portion 10a and the second portion 10b described above, the cooler 70 is arranged to cool at least the outer wall 12a of the first portion 10a.

Specifically, the cooling channel 71 of the water-cooled cooler 70 is arranged along the outer periphery of the portion of the outer wall 12 of the sample chamber 10 surrounding the sample container 40 (for example, the outer wall 12a of the first portion 10a). be done.

Further, when the high-frequency induction heating coil 21 is arranged along the outer periphery of the sample chamber 10, the cooling flow path 71 of the water-cooled cooler 70 is between the coil 21 and the outer wall 12 of the sample chamber 10. placed in

That is, when the high-frequency induction heating coil 21 is arranged along the outer circumference of the first portion 10a of the sample chamber 10, the cooling flow path 71 of the cooler 70 is formed between the coil 21 and the outer wall 12a of the first portion 10a. placed in between.

Cooler 70 may be arranged to cool a portion of outer wall 12 of sample chamber 10 surrounding at least a portion of heat transfer member 50 . That is, in the case where the heat transfer member 50 includes the carbon member 51 and the metal member 52 described above, the cooler 70 includes a portion of the outer wall 12 of the sample chamber 10 surrounding at least the carbon member 51 (for example, the carbon member 51 is It is arranged to cool the outer wall 12a) of the surrounding first portion 10a.

Specifically, the cooling channel 71 of the water-cooled cooler 70 is defined by at least a portion of the outer wall 12 of the sample chamber 10 that surrounds the carbon member 51 of the heat transfer member 50 (for example, the first portion 10a that surrounds the carbon member 51). along the outer circumference of the outer wall 12a) of the

The detector 30 is connected to the sample chamber 10 and detects the desorption gas generated from the solid sample S heated within the sample chamber 10 in the thermal desorption analysis using the apparatus 1 .

The detector 30 is not particularly limited as long as it can detect desorbed gas from the solid sample S, but is preferably a mass spectrometer, for example. The mass spectrometer is not particularly limited, but is preferably, for example, a quadrupole mass spectrometer (QMS) or a magnetic sector mass spectrometer, particularly preferably a QMS.

The apparatus 1 includes a piping channel 80 connecting the sample chamber 10 and the detector 30, as shown in FIG. In the temperature programmed desorption analysis, the desorption gas generated from the solid sample S heated in the sample chamber 10 passes from the internal space 11 of the sample chamber 10 through the piping flow path 80 to the detector 30. reach.

The device 1 may include a channel heater 81 that heats the piping channel 80, as shown in FIG. The channel heater 81 is arranged, for example, along the outer circumference of the portion of the piping channel 80 between the sample chamber 10 and the detector 30 . The channel heater 81 is preferably, for example, a heater (for example, a tape heater) including a heating wire.

The apparatus 1 may include a decompression device for decompressing the interior space 11 of the sample chamber 10 and/or the interior of the piping channel 80 . The decompression device is connected to the piping channel 80, for example. In this case, the decompression device decompresses the internal space 11 of the sample chamber 10 through a part of the piping channel 80 .

The decompression device is not particularly limited as long as it can form a decompressed space, but is preferably a decompression pump, for example. The vacuum pump is preferably, for example, a rotary pump (RP) and/or a turbomolecular pump (TMP).

Specifically, as shown in FIG. 1, the apparatus 1 may include a vacuum pump 90 arranged downstream of the detector 30 (the side of the detector 30 opposite to the sample chamber 10). This decompression pump 90 decompresses the sample chamber 10 , the piping channel 80 and the detector 30 . Vacuum pump 90 is preferably, for example, TMP.

The device 1 may also include a decompression pump 91 connected to a portion of the piping channel 80 between the sample chamber 10 and the detector 30, as shown in FIG. This decompression pump 91 is used for vacuum drying the mixture M frozen in the sample container 40 in the sample chamber 10, as will be described later. The decompression pump 91 is preferably RP, for example.

Further, the apparatus 1 may include a decompression pump 92 connected to a portion of the piping channel 80 between the decompression pump 91 and the detector 30, as shown in FIG. This decompression pump 92 is used to create a high vacuum in the internal space 11 of the sample chamber 10 . The vacuum pump 92 is preferably TMP, for example.

The device 1 may include a pressure gauge P1 for measuring the pressure in the piping channel 80, as shown in FIG. With this pressure gauge P1, the pressure state in the piping channel 80 (for example, presence or absence of gas leakage) can be monitored. Further, the piping flow path 80 may include valves V1, V2, V3, V4 and V5 as shown in FIG.

The apparatus 1 may further include a gas supply channel 82 for supplying gas to the sample chamber 10, connected to the piping channel 80, as shown in FIG. A gas supply source (for example, a gas cylinder) 83 may be connected to the gas supply channel 82 .

In this case, a gas reservoir 84 may be arranged between the gas supply source 83 and the piping channel 80 . A pressure gauge P<b>2 may also be connected to the gas reservoir 84 . The gas supply channel 82 may include valves V6 and V7 as shown in FIG.

Next, a thermal desorption analysis method (hereinafter referred to as "this method") according to this embodiment will be described. This method is a thermal desorption spectrometry method in which a solid sample is analyzed by the thermal desorption method using the above-described thermal desorption spectrometer (apparatus 1).

FIG. 3 shows the main steps involved in one example of this method. For example, as shown in FIG. 3, the method includes: storing a mixture M of a solid sample S and a liquid L in a sample container 40 in a sample chamber 10 (S101); freezing the mixture M in the sample container 40 by cooling the cooled portion 50b of the member 50 (S102); The mixture M is dried (S103), and the solid sample S left in the sample container 40 by the drying of the mixture M is analyzed by the temperature programmed desorption method while being heated by the heater 20. (S104).

In step S101, first, a mixture M is prepared by mixing a sample S and a liquid L. As shown in FIG. The resulting mixture M is then placed in the sample container 40 within the sample chamber 10 of the device 1 . Specifically, when the sample chamber 10 includes a first portion 10a and a second portion 10b that are separably connected, the first portion 10a containing the sample container 40 is separated from the second portion 10b and exposed. A mixture M is accommodated in the sample container 40 .

When the internal space 11 of the sample chamber 10 is preliminarily decompressed, first, gas is supplied from the gas supply source 83 to the internal space 11 via the gas supply channel 82 to increase the pressure, and then the first portion 10a and the It separates from the second part 10b.

That is, for example, when using the device 1 shown in FIG. The gas held in 84 (the gas was previously introduced into the gas reservoir 84 from the gas supply source 83 with the valve V open) is supplied to the internal space 11 of the sample chamber 10 to fill the internal space. 11 is raised to normal pressure.

After that, the valve V6 of the gas supply channel 82 is closed to stop the gas supply, the first portion 10a of the sample chamber 10 is separated from the second portion 10b, and the mixture M is put into the concave portion 41 of the sample container 40.

The solid sample S is not particularly limited as long as it is a solid sample to be analyzed by the thermal desorption method. , one or more selected from the group consisting of fluororesins and rubber materials) and biomaterials (e.g., one or more selected from the group consisting of nucleic acids and biological proteins). , preferably a carbon material.

When the solid sample S is a carbon material, the content of carbon atoms in the carbon material may be, for example, 70% by weight or more, 75% by weight or more, or 80% by weight or more. may be 85% by weight or more, or 90% by weight or more.

The liquid L is not particularly limited as long as it is a liquid that can be mixed with the solid sample S. For example, water, heavy water, alcohols (e.g., one or more selected from the group consisting of methanol, ethanol, and propanol), and It may be one or more selected from the group consisting of acetone, preferably water and/or heavy water.

A mixture M includes a solid sample S and a liquid L. The mixture M may be a suspension containing a liquid L and a solid sample S dispersed in the liquid L. Specifically, the mixture M includes, for example, a carbon material and protic hydrogen atoms contained in the carbon material (for example, protic hydrogen atoms contained in functional groups bonded to the carbon structure of the carbon material) deuterium atoms It may be a suspension prepared by mixing heavy water for replacing with. In this case, the mixture M contains heavy water and carbon material dispersed in the heavy water.

The content of the liquid L in the mixture M is not particularly limited. It may be 70% by weight or more and 99% by weight or less, or may be 80% by weight or more and 99% by weight or less.

In step S102, by cooling the portion to be cooled 51 of the heat transfer member 50 connected to the sample container 40, the sample container 40 is cooled via the heat transfer member 50, and the sample container 40 is cooled. The mixture M in the sample container 40 is cooled through the air, and finally the mixture M is frozen in the sample container 40 .

Specifically, when the first portion 10a of the sample chamber 10 is separated from the second portion 10b and the mixture M is accommodated in the sample container 40, first, the first portion 10a is reconnected to the second portion 10b. , the sealed internal space 11 is formed, and then the cooled portion 50b of the heat transfer member 50 is cooled to cool and freeze the mixture M held in the sample container 40 within the internal space 11. do.

During cooling until the mixture M freezes in step S102, the internal space 11 of the sample chamber 10 is not decompressed (that is, the mixture M is cooled in the internal space 11 at normal pressure until the mixture M freezes. ), or the pressure may be reduced.

The temperature for cooling the cooled portion 50b of the heat transfer member 50 is not particularly limited as long as the temperature is low enough to freeze the mixture M in the sample container 40 cooled via the heat transfer member 50. For example, - It may be 10° C. or lower, −50° C. or lower, −100° C. or lower, or −150° C. or lower.

The method for cooling the cooled portion 50b of the heat transfer member 50 is not particularly limited as long as the mixture M in the sample container 40 cooled via the heat transfer member 50 is frozen. A method of contacting the cooled portion 50b of 50 with the coolant is preferably used. The refrigerant is not particularly limited as long as it is a fluid, but is preferably liquid refrigerant R (for example, liquid nitrogen), for example.

Specifically, when the portion to be cooled 50b of the heat transfer member 50 is formed to protrude, as shown in FIG. Thus, the cooled portion 50b is cooled.

In step S103, after freezing the mixture M, the internal space 11 of the sample chamber 10 is decompressed to dry the frozen mixture M in the sample container 40 . That is, in this method, the mixture M containing the solid sample S and the liquid L is frozen in the sealed internal space 11 of the sample chamber 10 of the device 1, and then the sealed internal space 11 is decompressed. to dry the frozen mixture M.

Specifically, for example, when using the device 1 shown in FIG. The frozen mixture M is dried in the internal space 11 by depressurizing the internal space 11 of the .

That is, the frozen component of the liquid L contained in the frozen mixture M is sublimated and discharged out of the internal space 11 of the sample chamber 10 . As a result, the solid sample S contained in the mixture M remains in the sample container 40 .

In step S104, the solid sample S left in the sample container 40 by drying the mixture M is analyzed by the temperature programmed desorption method while being heated by the heater 20. FIG. That is, in this method, the mixture M containing the solid sample S and the liquid L is freeze-dried in the sealed internal space 11 of the sample chamber 10 of the device 1, and then, in the internal space 11 that is decompressed as it is, , the temperature programmed desorption analysis of the solid sample S is performed.

Specifically, for example, when using the apparatus 1 shown in FIG. 1, after reducing the pressure in the internal space 11 of the sample chamber 10 to a value suitable for thermal desorption analysis, With V3 and V4 open, cooling by the cooler 70 and heating of the solid sample S by the heater 20 (for example, high-frequency induction heating) are started.

In addition, after freeze-drying the mixture M and before starting the thermal desorption analysis, the valve V5 arranged between the piping channel 80 and the decompression pump 92 is opened, and the decompression pump 92 is driven so that the sample The internal space 11 of the chamber 10 may be highly evacuated by highly depressurizing the internal space 11 .

After that, desorption gas generated from the heated solid sample S is detected by the detector 30 . That is, the desorbed gas generated in the internal space 11 of the sample chamber 10 passes through the piping channel 80, reaches the detector 30, and is detected.

Note that it is not necessary to cool the cooled portion 50b of the heat transfer member 50 during the thermal desorption analysis of the solid sample S in the sample container 40 . Therefore, in this method, the thermal desorption analysis of the solid sample S may be performed without cooling the cooled portion 50 b of the heat transfer member 50 . However, the cooled portion 50b of the heat transfer member 50 may be cooled during the thermal desorption analysis of the solid sample S as necessary.

That is, in this method, the mixture M containing the sample S is freeze-dried in the sample chamber 10 of the apparatus 1, and the sample S remaining after freeze-drying is continuously subjected to thermal desorption analysis. Specifically, after freeze-drying the mixture M in the sample chamber 10 , without opening the sample chamber 10 , the temperature-programmed desorption analysis of the sample S is continuously performed in the sample chamber 10 .

Thus, according to the present method, in the internal space 11 of the sample chamber 10 of the apparatus 1, the mixture M containing the solid sample S and the liquid L is freeze-dried, and the temperature of the solid sample S after freeze-drying is increased. The desorption analysis can be continuously performed while the internal space 11 is maintained in a sealed state.

Next, specific examples according to this embodiment will be described.

[Preparation of mixture]
As the solid sample S, a carbon material was used. Specifically, commercially available activated carbon (MSC30, Kansai Coke & Chemicals Co., Ltd.) was used. As the liquid L, the carbon material is subjected to a process (HD substitution process) in which the protic hydrogen atoms contained in the functional groups bonded to the carbon structure of the carbon material are substituted with deuterium atoms. Heavy water ( _D2O ) was used.

First, the carbon material was placed in a vacuum-sealable vial and vacuum-dried. Next, while the vial was vacuum-sealed, heavy water (D ₂ O) was injected into the vial using a syringe. Thus, a suspension containing heavy water and the carbon material dispersed in the heavy water was prepared as the mixture M in a vacuum-sealed vial. Further, the suspension in the vial was heated to 60° C. and held for 24 hours in order to promote the exchange reaction between the protic hydrogen atoms contained in the carbon material and the deuterium atoms in the heavy water.

[Freeze-drying of the mixture]
A suspension containing a carbon material was freeze-dried using the apparatus 1 having the configuration shown in FIG. That is, first, gas (argon) was supplied from the gas supply source 83 to the internal space 11 of the sample chamber 10 via the gas supply channel 82 , so that the internal space 11 was pressurized to normal pressure. Next, the first part 10a made of quartz was separated from the second part 10b made of stainless steel, and the suspension containing the carbon material was transferred from the vial into the recess 41 of the sample container 40 .

In addition, the first portion 10a was connected with the second portion 10b to form a sealed internal space 11 within the sample chamber 10 . Thus, the suspension was accommodated in the sample container 40 in the internal space 11 of the sample chamber 10 .

Thereafter, by immersing the projecting portion 50b of the heat transfer member 50 to be cooled in liquid nitrogen contained in the metal container C, the suspension in the sample container 40 is cooled through the heat transfer member 50. was cooled and finally the suspension was frozen.

Next, by driving the decompression pump 91 (RP) to reduce the pressure in the internal space 11 of the sample chamber 10 holding the frozen suspension, the frozen suspension is dried in the internal space 11. let me As a result, the sample container 40 was subjected to the HD replacement treatment, and the dried carbon material remained.

[Thermal desorption analysis]
The freeze-dried carbon material was analyzed by the thermal desorption method using this apparatus 1 . That is, after the freeze-drying described above, a high-vacuum interior space 11 of 1×10 ⁻³ Pa or less is formed by further driving the decompression pump 92 (TMP) without pressurizing the interior space 11 of the sample chamber 10. bottom.

After that, the heater 20, which is a high-frequency induction heater, and the water-cooled cooler 70 are operated to increase the temperature in the high-vacuum internal space 11 of the sample chamber 10 from 0°C to 1600°C at a temperature increase rate of 10°C/min. The carbon material was heated while increasing the .

Then, the desorbed gas (specifically, CO, CO ₂ , H ₂ , HD, D ₂ , H ₂ O, DHO and D ₂ O) generated during the period when the temperature rises from 0° C. to 1600° C. Measured with detector 30 (QMS). In addition, for comparison, the carbon material not subjected to the HD replacement treatment was similarly measured for the desorbed gas by the temperature programmed desorption method.

[result]
Figures 4A and 4B show the thermal desorption spectra of CO and _CO2 and the thermal desorption spectra of _H2 obtained for a carbon material (MSC) not subjected to the HD substitution treatment, respectively. show. FIGS. 5A and 5B show temperature-programmed desorption spectra of CO and CO obtained for a carbon material ₍ MSC(D ₂ O)) subjected to HD substitution treatment, and H ₂ , HD and D ₂ are shown respectively.

As shown in FIGS. 5A and 5B, even when the suspension of the carbon material containing heavy water for the HD replacement treatment is freeze-dried in the present apparatus and subsequently subjected to thermal desorption analysis, the results shown in FIGS. A temperature-programmed desorption spectrum similar to that obtained when the temperature-programmed desorption analysis was performed on the carbon material that was dried without freeze-drying the suspension shown in FIG. 4B was obtained.

Further, as shown in FIG. 5B, in the temperature-programmed desorption spectrum of the carbon material subjected to the HD substitution treatment, functional groups in which protic hydrogen atoms are replaced with deuterium atoms by the HD substitution treatment Deuterium (HD) and deuterium (D ₂ ) gases were detected.

Claims (10)

a sample chamber having an internal space that can be decompressed;
a heater for heating the solid sample in the sample chamber; and
a detector for detecting desorption gas generated from the solid sample heated in the sample chamber;
including
The sample chamber includes, within the interior space,
a sample container for containing the solid sample and liquid mixture; and
a heat transfer member having a connecting portion heat-transferably connected to the sample container and a cooled portion cooled to freeze the mixture in the sample container;
including,
Thermal desorption analyzer. The portion to be cooled of the heat transfer member is formed to protrude from the internal space of the sample chamber,
The thermal desorption spectrometer according to claim 1. The heat transfer member is a rod-shaped member having one end as the connecting portion and the other end as the cooled portion.
The thermal desorption spectrometer according to claim 1 or 2. The heat transfer member includes a carbon member having the connecting portion,
The thermal desorption spectrometer according to any one of claims 1 to 3. The heat transfer member includes a metal member having the portion to be cooled,
The thermal desorption spectrometer according to any one of claims 1 to 4. the sample chamber includes a first portion that accommodates the sample container and a second portion that accommodates the heat transfer member;
The first part and the second part are separably connected,
The thermal desorption spectrometer according to any one of claims 1 to 5. The heater is a heater that heats the solid sample to 500 ° C. or higher.
The thermal desorption spectrometer according to any one of claims 1 to 6. The heater is a high-frequency induction heater,
The thermal desorption spectrometer according to any one of claims 1 to 7. the sample chamber further comprising a cooler;
The thermal desorption spectrometer according to any one of claims 1 to 8. A thermal desorption analysis method for analyzing a solid sample by thermal desorption using the thermal desorption spectrometer according to any one of claims 1 to 9,
containing the solid sample and liquid mixture in the sample container within the sample chamber;
freezing the mixture in the sample container by cooling the cooled portion of the heat transfer member connected to the sample container;
depressurizing the interior space of the sample chamber to dry the frozen mixture in the sample container; and
analyzing the solid sample left in the sample container by drying the mixture by a temperature programmed desorption method while being heated by the heater;
including,
Thermal desorption analysis method .

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