JP2003075379A - Analyzer for temperature elevation elimination - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow a sample to be replaced easily by simple structure, and to preclude the atmospheric air from intruding into a sample chamber or the like in the replacement of the sample for improving measurement accuracy. SOLUTION: This analyzer is provided with the freely openable and closable sample chamber 1a for arranging the sample, an infrared heating furnace 5 for heating the sample arranged in the sample chamber 1a, a mass spectrometer 6 for detecting gas eliminated from the sample by heating, a measuring chamber 3a for arranging a detecting part of a detecting means, and a gas flow passage 2a for communicating the sample chamber 1a with the measuring chamber 3a to be freely separable from the sample chamber 1a. The analyzer is provided also with a sample chamber protecting means for preventing the atmospheric air from intruding into the opened sample chamber 1a, using inert gas, and a flow passage protecting means for preventing the atmospheric air from intruding into the gas passage 2a opened and separated, using the inert gas.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal desorption analyzer which is one of thermal analyzers.

[0002]

2. Description of the Related Art The temperature programmed desorption analysis method is a thermal analysis method for measuring the amount of evolved gas desorbed from a sample as a function of the sample temperature when the temperature of a solid sample is raised at a constant rate. Yes, it is also called TDS (Thermal Desorption Spectroscopy) or TPS (Temperature Programmed Desorption). This temperature programmed desorption analysis method comprises a sample chamber in which a sample is placed, a heating furnace for heating the sample in the sample chamber, a mass spectrometer as a detection means for detecting a gas desorbed from the sample, and a high vacuum atmosphere. It is realized by a thermal desorption analyzer equipped with a turbo molecular pump (TMP) for forming a measurement environment.

Here, in the conventional general thermal desorption spectroscopy apparatus, the detection part of the mass spectrometer is arranged in the main chamber,
The sample chamber is detachable from the main body chamber, and when the sample is exchanged, the sample chamber is separated from the main body chamber and opened to the atmosphere. Therefore, it is inevitable that the atmosphere flows into the sample chamber during the sample exchange, and atmospheric components including moisture adhere to the inner surface of the sample chamber.

[0004]

When atmospheric components including moisture adhere to the inner surface of the sample chamber during the sample exchange, the sample chamber is heated when the sample chamber is heated in the subsequent desorption analysis of the sample. Atmospheric components adhering to the inner surface of the are desorbed to generate gas. Since this gas is detected by the mass spectrometer together with the gas desorbed from the sample, there is a problem that the gas desorbed from this atmospheric component becomes the background and the resolution of the desorbed gas peculiar to the sample decreases. It was

Therefore, conventionally, a thermal desorption analyzer having a structure as shown in FIG. 4 has been developed. The conventional thermal desorption analyzer shown in FIG. 1 includes a sample exchange chamber 100 called a load lock chamber, and a gate valve 102 allows opening and closing between the sample exchange chamber 100 and the sample chamber 101. . When exchanging samples, gate valve 1
02 is opened to take out the measured sample S from the sample chamber 101, the sample S is placed in the sample exchange chamber 100, the gate valve 102 is closed, and then an opening / closing door for sample exchange provided in the sample exchange chamber 100 (see FIG. Open (not shown) to replace the sample.

In the above-mentioned conventional thermal desorption analyzer, a transfer mechanism incorporated in the apparatus is used for taking out the measured sample S from the sample chamber 101 and transferring a new measurement sample to the sample chamber 101. Since this transport mechanism has a complicated and large-sized structure, it is inevitable that the entire apparatus becomes large-sized. In addition, since a large volume is required in the sample chamber 101 in which the sample is transferred using this transfer mechanism, not only it takes time to evacuate the vacuum during measurement, but also it is difficult to realize a high vacuum and the measurement accuracy deteriorates. There was a problem to Also,
The sample may fall off from the transport mechanism during the sample exchange, and the work of taking out the dropped sample was extremely complicated.

The present invention has been made in view of the circumstances peculiar to such a conventional thermal desorption analyzer, and the sample can be easily exchanged with a simple structure. The purpose is to prevent intrusion and improve the measurement accuracy.

[0008]

In order to achieve the above object, the thermal desorption spectroscopy apparatus of the present invention heats a sample chamber in which a sample is placed and an openable and closable sample chamber. Heating means, a detection means having a detection part for detecting a gas desorbed from the sample by heating, and a sample chamber protection means for blocking the inflow of the atmosphere into the opened sample chamber by using an inert gas, It is characterized by being provided (Claim 1).

During sample replacement, the sample chamber protection means uses an inert gas to block the inflow of the atmosphere into the sample chamber, so there is no risk of atmospheric components adhering to the inside of the sample chamber, etc. It is possible to prevent the measurement accuracy from deteriorating due to the mixing of the atmospheric component. Moreover, sample exchange can be easily performed from the opening of the open sample chamber, and since the sample chamber protection means has a mechanism using an inert gas, the device is not made large.

Further, the temperature programmed desorption analyzer of the present invention has, in addition to the above configuration, a measurement chamber in which a detection portion of a detection means is arranged, the measurement chamber and the sample chamber are communicated with each other, and the sample chamber is separated. It is also possible to have a configuration including a free gas passage and a passage protection means for blocking the inflow of the atmosphere into the gas passage opened by disconnecting the sample chamber by using an inert gas. (Claim 2).

Atmosphere may intrude into the gas communication path from which the sample chamber is separated from the opening and adhere to the inner surface thereof. Adhesion of the atmosphere to the inner surface of the gas communication path causes a decrease in measurement accuracy, as in the case where the atmosphere adheres to the inner surface of the sample chamber. Therefore, with the above-mentioned configuration, when the sample is replaced, the conduction path protection means uses the inert gas to prevent the inflow of the atmosphere into the gas conduction path, so that the atmospheric component may adhere to the inner surface of the gas conduction path. Therefore, it is possible to more reliably prevent the measurement accuracy from being deteriorated due to the mixing of atmospheric components into the measurement atmosphere.

Here, the sample chamber protection means is configured to supply an inert gas into the sample chamber and discharge the inert gas from the opening of the sample chamber, or to supply the inert gas along the opening surface of the sample chamber. The layer may be discharged to form a layer of an inert gas on the opening surface (claims 3 and 4).

Further, the conductive path protecting means is configured to supply an inert gas into the conductive path and discharge the inert gas from an opening of the conductive path, or an inert gas along the opening surface of the conductive path. Can be discharged to form a layer of an inert gas on the opening surface (claims 3 and 4).

Furthermore, if a pressure adjusting means for gently supplying an inert gas is provided in the closed sample chamber, the sample chamber kept in a high vacuum during measurement can be gently adjusted to near atmospheric pressure. It is possible to realize suitable pressure adjustment in the sample chamber, particularly when taking out a sample such as a powder sample that may be scattered due to a sudden pressure change (claim 5).

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will now be described in detail with reference to the drawings. 1 and 2
FIG. 1 is a configuration diagram schematically showing a thermal desorption analysis device according to a first embodiment of the present invention. The thermal desorption analyzer shown in these figures includes a protective tube 1, a relay chamber 2, and a measurement chamber 3.

The protective tube 1 is composed of a tube body having heat resistance such as a quartz tube having a closed end, and the inside of its hollow portion forms a sample chamber 1a. A sample S is placed in the sample chamber 1a. Here, the sample S is attached to the tip of the sample holder 4 extending from the relay chamber 2.

An infrared heating furnace 5 as a heating means is installed around the protective tube 1, and the infrared heating furnace 5 uniformly heats the sample S placed in the sample chamber 1a from its surroundings. The protection tube 1 and the infrared heating furnace 5 can be moved integrally in the lateral direction in the figure, and the movement allows the base end opening 1b of the protection tube 1 to be detachable from the connection portion 2b of the relay chamber 2. There is.

The hollow portion of the relay chamber 2 has a gas passage 2a.
And the measurement chamber 3 formed in the measurement chamber 3
a and the sample chamber 1a are connected in series via the gas communication path 2a. The detection part (ion source) 6a of the mass spectrometer 6 (detection means) is arranged in the measurement chamber 3a, and the gas desorbed from the sample S by heating is captured by the mass spectrometer 6 in the measurement chamber 3a. Then, it is configured to detect.

A turbo molecular pump 7 and a rotary pump 8 for roughing are connected to the measuring chamber 3. The turbo molecular pump 7 is provided from the sample chamber 1a to the measurement chamber 3
It has a function of vacuuming and exhausting unnecessary gas remaining in the closed space up to a from the measurement chamber 3a side and guiding the gas desorbed from the sample S in the sample chamber 1a to the measurement chamber 3a. There is.

In this embodiment, the sample chamber 1a and the measurement chamber 3a
Are connected to each other in series via the gas communication path 2a, and are evacuated from the measurement chamber 3a side by the turbo molecular pump 7, so that the internal gas smoothly flows with vacuum evacuation and can be quickly removed. Moreover, the desorbed gas from the sample S generated in the sample chamber 1a can be efficiently flowed to the measurement chamber 3a.

A gate valve 9 is provided between the relay chamber 2 and the measurement chamber 3, and the gate valve 9 is provided.
The opening / closing operation of allows the opening / closing between the gas communication path 2a and the measurement chamber 3a. A rotary pump 11 for roughing is connected to the peripheral wall of the relay chamber 2 via a gate valve 10.

Further, in this embodiment, the relay chamber 2
A gate valve 20 is provided on the peripheral wall of the inert gas supply passage 2a through the gate valve 20 to the gas passage 2a.
1 is connected. In the inert gas supply path 21,
A dry inert gas (for example, nitrogen gas, argon gas, helium gas) can be supplied from a gas supply source (not shown) through the second electromagnetic valves 22 and 23.
The gate valve 20, the inert gas supply path 21, and the first and second electromagnetic valves 22 and 23 use an inert gas to flow the atmosphere into the gas communication path 2a opened by disconnecting the protection tube 1. Conducting path protection means for blocking is constructed.

A throttle valve 24 is provided in the conduit connecting to the second electromagnetic valve 23.
The inert gas supplied via 3 is the throttle valve 24
Is suppressed by. The throttle valve 24 and the inert gas supply path 21 extending from the second electromagnetic valve 23 to the gate valve 20 constitute pressure adjusting means for gently supplying the inert gas into the closed sample chamber 1a.

A gate valve 25 is also provided at the tip of the protective tube 1, and an inert gas supply passage 26 is connected to the sample chamber 1a via the gate valve 25. A dry inert gas is supplied to the inert gas supply path 26 from a gas supply source (not shown) via the first electromagnetic valve 22. The gate valve 25, the inert gas supply passage 26, and the first electromagnetic valve 22 constitute a sample chamber protection unit that blocks the inflow of the atmosphere into the opened sample chamber 1a by using an inert gas.

The protective tube 1 is provided with a vacuum gauge 27 for measuring the degree of vacuum in the sample chamber 1a.

Next, an operation procedure for sample exchange in the thermal desorption analyzer having the above-mentioned configuration will be described. As shown in FIG. 1, when the temperature chamber desorption analysis is completed in an atmosphere in which the sample chamber 1a, the gas communication path 2a and the measurement chamber 3a are hermetically sealed and the inside thereof is maintained in a high vacuum, first, the gate valve 9 is turned on. Then, the measurement chamber 3a is closed and the vacuum is maintained. Next, the gate valve 20 and the second electromagnetic valve 23 are opened to slowly supply the inert gas from the inert gas supply passage 21 to the gas conducting passage 2a to the sample chamber 1a, and then the gas conducting passages 2a to 2a. The internal pressure of the sample chamber 1a is raised to near atmospheric pressure. The amount of the inert gas supplied here per unit time is set to a very small amount, thereby suppressing a rapid pressure change and preventing scattering of the powder sample and the like.

After the internal pressure of the gas passage 2a to the sample chamber 1a rises to near atmospheric pressure, the protective tube 1 is moved to the left in the drawing to disconnect the protective tube 1 from the relay chamber 2. By this operation, the sample S is exposed from the protective tube 1, and the connecting portion 2b of the relay chamber 2 and the base end opening portion 1b of the protective tube 1 are exposed.
Are released to the atmosphere (see FIG. 2).

In synchronism with the operation of disconnecting the protective tube 1 from the relay chamber 2, the first electromagnetic valve 22 is opened and the inert gas supply passage 21 and the gate valve 20 are passed through the gas passage 2a to the dry passage. The active gas a is vigorously supplied. The inert gas a supplied in this manner fills the gas communication path 2a and is discharged from the connection portion 2b (opening), so that the inflow of atmospheric air into the gas communication path 2a from the outside is an inert gas. blocked by a.

At the same time that the first electromagnetic valve 22 is opened, the gate valve 25 is also opened, and the inert gas supply passage 2 is opened.
A dry inert gas a is vigorously supplied from 6 into the sample chamber 1a. The inert gas a supplied in this way fills the sample chamber 1a and the base end opening 1 of the protective tube 1
Since it is released from b, the inflow of air from the outside into the sample chamber 1a is blocked by the inert gas a.

Moreover, in the present embodiment, the sample holder 4 is arranged on substantially the same axis as the protective tube 1, and the sample holder 4 is protected when the sample holder 4 is exposed by the movement of the protective tube. It is arranged to face the proximal end opening 1b of the tube 1. Therefore, since the inert gas a released from the base end opening 1b of the protective tube 1 flows around the sample holder 4 to form a layer of a gas curtain, adsorption of atmospheric components to the sample holder 4 is also suppressed. To be done.

Since the sample holder 4 is exposed from the protective tube 1, the sample S can be replaced very easily. Then, after the sample exchange is completed, the protective tube 1 is moved to connect the base end opening 1b to the connecting portion 2b of the relay chamber 2 to seal the sample chamber 1a and the gas conducting path 2a. Further, in synchronization with this operation, the gate valve 20, the gate valve 25, the first electromagnetic valve 22 and the second electromagnetic valve 23 are closed, and the sample chamber 1a and the gas passage 2a are closed.
The supply of the inert gas a to the is stopped. A leak valve (not shown) is provided in the protective tube 1 so that the pressure in the sample chamber 1a is released via the leak valve when the pressure in the sample chamber 1a reaches a certain pressure or more. It is configured.

After the series of operations relating to the sample exchange is completed, the gate valve 10 is opened and the rotary pump 11 is driven to discharge the inert gas remaining in the sample chamber 1a to the gas passage 2a. Then, the gate valve 9 is opened, the gas communication path 2a and the measurement chamber 3a are communicated with each other, and the next measurement operation is performed.

FIG. 3 is a schematic diagram showing a thermal desorption analyzer according to the second embodiment of the present invention. In addition, the same or corresponding portions as those in FIGS. 1 and 2 described above are denoted by the same reference numerals. In the second embodiment shown in FIG. 3, a gate valve 30 that discharges an inert gas is provided along the opening surface at the edge of the connecting portion 2b in the relay chamber 2, and the gate valve 30 is an inert gas. Supply path 31
It is connected to the first electromagnetic valve 22 via. Also,
A gate valve 32 that discharges an inert gas along the opening surface of the base end opening 1b is also provided at the base end edge of the protection tube 1, and the gate valve 32 is provided via an inert gas supply passage 33. It is connected to the first electromagnetic valve 22.

When the protective tube 1 and the relay chamber 2 are opened during the sample exchange, the above gate valves 30, 3 are opened.
2 is opened, and the dry inert gas a is supplied from the first electromagnetic valve 22 through the inert gas supply paths 31 and 33 to the connecting portion 2
It discharges along the opening surface of b and the opening surface of the base end opening 1b. Thereby, the connecting portion 2b in the relay chamber 2
Since the curtain (layer) of the inert gas a is formed on the opening surface of, the invasion of the atmosphere into the gas communication path 2a is prevented. Similarly, since the curtain (layer) of the inert gas a is also formed on the opening surface of the base end opening 1b of the protective tube 1, the invasion of the atmosphere into the sample chamber 1a is prevented.

[0035]

As described above, according to the present invention,
During sample replacement, the sample chamber protection means uses an inert gas to block the inflow of air into the sample chamber, so there is no risk of atmospheric components adhering to the inside of the sample chamber, etc. It is possible to prevent deterioration of measurement accuracy due to mixing. Moreover, the sample exchange can be easily performed from the opening of the open sample chamber, and the sample chamber protection means has a mechanism using an inert gas.
There is no need to upsize the device.

Further, if the structure is provided with the conduction passage protection means, the passage passage protection means uses an inert gas to prevent the inflow of the atmosphere into the gas conduction passage when the sample is exchanged. Moreover, there is no risk of atmospheric components adhering, and it is possible to more reliably prevent a decrease in measurement accuracy due to the inclusion of atmospheric components in the measurement atmosphere.

[Brief description of drawings]

FIG. 1 is a configuration diagram schematically showing a thermal desorption analyzer according to a first embodiment of the present invention, showing a state in which a protective tube is closed.

FIG. 2 is a configuration diagram schematically showing the thermal desorption analysis apparatus according to the first embodiment of the present invention, showing a state in which a protection tube is opened.

FIG. 3 is a configuration diagram schematically showing a thermal desorption analysis apparatus according to a second embodiment of the present invention.

FIG. 4 is a configuration diagram schematically showing a conventional thermal desorption analysis apparatus.

[Explanation of symbols]

S: Sample 1: Protection tube 1 1a: sample chamber 1b: Base end opening 2: Relay chamber 2a: Gas conduit 2b: Connection part 3: Measuring chamber 3a: measurement room 4: Sample holder 5: Infrared heating furnace 6: Mass spectrometer 6a: Detection unit (ion source) 7: Turbo molecular pump 8, 11: Rotary pump 9, 10, 20, 25, 30, 32: Gate valve 21, 26, 31, 33: Inert gas supply path 22: First electromagnetic valve 23: Second electromagnetic valve 24: Throttle valve 27: Vacuum gauge

Claims (5)

[Claims] 1. A sample chamber in which a sample is placed and which can be opened and closed, a heating unit for heating the sample placed in the sample chamber, and a detection unit having a detection unit for detecting a gas desorbed from the sample by heating. And a sample chamber protecting means for blocking the inflow of air into the opened sample chamber by using an inert gas. 2. The thermal desorption analysis apparatus according to claim 1, wherein the measurement chamber in which the detection unit of the detection means is disposed, and the measurement chamber and the sample chamber are connected to each other and the sample chamber can be separated. Thermal desorption comprising a gas passage and a passage protection means for blocking the inflow of air into the gas passage opened by disconnecting the sample chamber by using an inert gas. Analysis equipment. 3. The temperature programmed desorption analyzer according to claim 2, wherein the sample chamber protection means supplies an inert gas into the sample chamber and discharges the inert gas from an opening of the sample chamber. The thermal desorption analyzer is characterized in that the conduction path protection means is configured to supply an inert gas into the conduction path and discharge the inert gas from an opening of the conduction path. 4. The temperature programmed desorption analyzer according to claim 2, wherein the sample chamber protection means releases an inert gas along an opening surface of the sample chamber, and the inert gas is discharged to the opening surface. It is a structure that forms a layer, the conductive path protection means is a structure that discharges an inert gas along the opening surface of the conductive path, to form a layer of an inert gas in the opening surface. Thermal desorption analyzer. 5. The temperature programmed desorption analyzer according to claim 1, further comprising pressure adjusting means for gently supplying an inert gas into the closed sample chamber. Thermal desorption analyzer.