JP2014081250A - Adsorption characteristic measurement instrument - Google Patents

Abstract

An adsorption characteristic measuring apparatus is configured to perform adsorption characteristic measurement on the next sample while measuring adsorption characteristic on one sample.
An adsorption characteristic measuring device includes an attachment part for attaching a sample tube and the like, a first adsorbate gas source for supplying adsorbate, an attachment part and the like, and a first adsorbate gas source. 38, a pressure gauge 94 that detects the pressure of the manifold 44, a pressure gauge 56 that detects the pressure of the sample tube 10 and the like, and a measurement control unit 100. The control unit repeatedly executes an introduction processing procedure 104 for introducing the adsorbate into the manifold 44 and a supply processing procedure 106 for supplying the adsorbate to the sample tube 10 and the like. Then, the adsorption amount is calculated based on the detection values of the pressure gauge 94 and the pressure gauge 56 for the sample 20 and the like inside the sample tube 10 to which the adsorbate is supplied.
[Selection] Figure 1

Description

  The present invention relates to an adsorption characteristic measuring apparatus, and more particularly to an adsorption characteristic measuring apparatus that measures adsorption characteristics for a plurality of samples.

Regarding the adsorption characteristic apparatus, Patent Document 1 discloses that in a measurement system of a container that is filled with a gas, a measurement sample is disposed inside, and has a certain volume, between the temperature T, the pressure P, and the adsorption amount n. It is stated that the relational expression Δn = Δn _i − (V / RT) × ΔP holds. Here, Δn is a change in the amount of gas adsorbed to the measurement sample (mol), Δn _i is an amount of gas supplied into or discharged from the container (mol), and ΔP is a pressure inside the container. Change (Torr), V is the volume (cm ³ ) of the container, R is a gas constant of 0.0624 cm ³ · Torr / K · mol, and T is the temperature (K) in the container.

Patent Document 2 states that accurate measurement of the gas adsorption amount requires an accurate value of the dead volume V _d , which is an apparent volume of a measurement sample tube in which a sample of unknown volume is accommodated. Yes. Therefore, helium gas is put into a reference volume part in which the geometric volume V _S is accurately measured in advance, and its pressure is set to π, and the pressure π ′ when the helium gas in the reference volume part is introduced into the measurement sample tube is obtained, It is disclosed that the dead volume V _d is obtained from πV _S = π ′ (V _S + V _d ).

JP 2011-112404 A JP 11-108733 A

In order to obtain the adsorption characteristics of the sample according to the principle described in Patent Document 1, the volume V and temperature T of the container are kept constant, Δn _i adsorbate is supplied to the sample, and the pressure change ΔP before and after the adsorption is measured. There must be. Here, it takes a considerable amount of time to cause the adsorption to such an extent that the pressure change ΔP occurs with the volume V and temperature T of the container being constant. Until ΔP can be measured, the adsorption characteristic measurement apparatus is exclusively used for the sample, and the adsorption characteristic measurement cannot be performed on the next sample.

  The objective of this invention is providing the adsorption | suction characteristic measuring apparatus which can perform the adsorption | suction characteristic measurement about the following sample, measuring the adsorption | suction characteristic about one sample.

  An adsorption characteristic measuring apparatus according to the present invention is an adsorption characteristic measuring apparatus that measures adsorption characteristics by supplying a predetermined adsorbate to a plurality of samples accommodated in each of a plurality of sample tubes. For the adsorbate supply section and the adsorbate via the plurality of attachment sections provided in each of the sample tube openings, the adsorbate supply section for supplying the adsorbate, each of the plurality of attachment sections, and the open / close valve for the sample tube A manifold connected via an on-off valve, a manifold pressure gauge for detecting the pressure of the manifold, a plurality of sample tube pressure gauges for independently detecting the internal pressures of the plurality of sample tubes, and a measurement control unit, The measurement control unit introduces the adsorbate into the manifold by opening the adsorbate on / off valve from the closed state to an open state arbitrarily determined from the closed state while all the plurality of sample tube on / off valves are closed. Procedure After the adsorbate opening / closing valve is returned to the closed state, the opening / closing valve for the sample tube is opened for any one of the plurality of sample tubes from the closed state to a predetermined opening period. The supply processing procedure for supplying the adsorbate to the sample accommodated in the sample tube is repeated, and the adsorbate is sequentially supplied to each of the plurality of sample tubes, with the total period of the introduction period and the valve opening period as a repeating unit. For each sample tube to which the adsorbate is supplied, the adsorption characteristic is measured based on the pressure of the manifold and the internal pressure of each sample tube.

Further, in the adsorption characteristic measuring apparatus according to the present invention, the measurement control unit is in an open state for a predetermined introduction period from the closed state to the open / close valve for the adsorbate while all of the plurality of sample tube open / close valves are closed. As a result, the manifold pressure at the end of the introduction period when the adsorbate is supplied to the manifold is obtained as P _Ii , the adsorbate on / off valve is returned to the closed state, and any one of the plurality of sample tubes is measured. As the target sample tube, when the open / close valve for the measurement target sample tube is opened from the closed state for a predetermined opening period, the adsorbate is supplied to the sample accommodated in the measurement target sample tube at the end of the valve opening period. The pressure of the manifold is acquired as P _Ii ^* , and the open / close valve for the measurement target sample tube is returned to the closed state after the valve opening period, and the time change of the pressure detected by the sample tube pressure detection unit corresponding to the measurement target sample tube is monitored. And pressure drop The internal pressure of the measurement target sample tube when it becomes an equilibrium state obtained as P _i ^*, the temperature of the manifold were volume and T _S as V _S, the temperature of the measurement target sample tube T _d urban death volume V _di In general, the introduction amount Δn _i of the adsorbate introduced into the measurement target sample tube using the gas constant R is generally Δn _i = (V _S / RT _S ) × (P _Ii −P _Ii ^* ) And the remaining amount of adsorbate Δn _di remaining in the dead volume of the sample tube to be measured is calculated as Δn _di = (V _di / RT _s ) × P _i ^* and is adsorbed to the sample inside the sample tube to be measured. The amount V _i of the adsorbate thus obtained is preferably obtained by V _i = (Δn _i −Δn _di ). Actually, it is preferable to calculate by the real gas equation of gas considering the non-ideality of the gas.

Further, in the adsorption characteristic measuring apparatus according to the present invention, it is preferable that the respective dead volumes V _di are obtained in advance for a plurality of sample tubes.

Further, in the adsorption characteristic measuring apparatus according to the present invention, the adsorption characteristic measuring apparatus measures the adsorption equilibrium pressure at a predetermined pressure, wherein the temperature of the manifold is T _S and the volume is V _S. the temperature T _d city death volume as V _di, using gas constant R, the introduction amount [Delta] n _i of adsorbate that is introduced into the measured sample _{tube, Δn i = (V S /} RT S) × Σ ^{_{(P Ii n -P Ii n *}} ) is calculated as to calculate the adsorbate remaining [Delta] n _di remaining dead volume of the measurement object sample tube as _{Δn di = (V di / RT} S) × P i *, measured The amount of adsorbate V _i adsorbed on the sample inside the target sample tube is preferably determined by V _i = (Δn _i −Δn _di ).

  With the above configuration, the adsorption characteristic measuring apparatus sequentially repeats each of the plurality of sample tubes, with the total period of the introduction period for introducing the adsorbate into the manifold and the valve opening period for supplying the adsorbate from the manifold to the sample tube as a repeating unit. Supply adsorbate. Since the introduction period and the valve opening period are times for transferring the adsorbate, the time is short, and after the adsorbate is sequentially supplied to each sample tube, the pressure change ΔP before and after the adsorption is measured for each sample tube. Since each sample tube is independently provided with a sample tube pressure detector, ΔP can be measured in parallel even if it takes time. In this way, the adsorption characteristic measurement for the next sample can be performed while the adsorption characteristic measurement for one sample is performed using one adsorption characteristic measurement apparatus.

In addition, the adsorption characteristic measuring apparatus obtains the pressure of the manifold at the end of the introduction period as P _Ii , obtains the pressure of the manifold at the end of the valve opening period as P _Ii ^* , and the pressure drop due to adsorption occurs in the sample tube to be measured. The pressure at the equilibrium state is acquired as P _i ^* , and the amount of adsorbate adsorbed on the sample inside the measurement target sample tube is obtained from these three pressures. Of these three pressures, P _Ii and P _Ii ^* are measured with a single pressure gauge, but can be acquired in a short time, so even if they are sequentially processed in series, it does not take much time. The other P _i ^* takes a long time, but since each pressure gauge is used, it can be processed in parallel. In this way, it is possible to efficiently perform adsorption characteristic measurement for a plurality of samples using a single adsorption characteristic measurement apparatus.

Further, in the adsorption characteristic measuring apparatus, the dead volume V _di is obtained in advance for a plurality of sample tubes. Therefore, even if measurement is sequentially performed using one adsorption characteristic measuring apparatus, the adsorption characteristic for each sample is obtained. The measurement accuracy can be improved.

  In addition, when the pressure falls below the target pressure during adsorption, a measurement point close to the target equilibrium pressure can be obtained by introducing the adsorbate again.

  Further, when the adsorption amount fluctuates beyond the target adsorption amount allowable amount, in order to measure the measurement point finely, the above steps are skipped, and the adsorption amount measurement point can be measured uniformly without leaving.

  Moreover, the dead volume with the sample at the time of measuring the adsorption amount is reduced by closing the open / close valve of the sample tube. As a result, the dead volume can be reduced as compared with the conventional measuring apparatus, and the adsorption amount measurement accuracy can be improved thereby.

  Since adsorption characteristics can be measured for a plurality of samples at the same time, the entire measurement time can be shortened by being able to shift to the next measurement point sequentially from the sample that has reached adsorption equilibrium.

It is a block diagram of the adsorption | suction characteristic measuring apparatus in embodiment which concerns on this invention. It is a flowchart which shows the operation | movement procedure in the adsorption | suction characteristic measuring apparatus of embodiment which concerns on this invention. In the adsorption characteristic measuring device of the embodiment concerning the present invention, it is a time chart which shows the change of the open / close timing of each on-off valve, and the detected value of each pressure gauge.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following, nitrogen gas is described as an adsorbate, but this is an example, and other substances may be used. In addition, the dead volume is calculated using helium gas that is not adsorbed to the sample even at the nitrogen adsorption temperature as in Patent Document 2, and the volume of the sample tube and the volume of the sample are measured in advance. The differential volume may be used as the dead volume.

  In the following, the number of sample tubes that can be measured continuously will be described as 3. However, this is an example, and a plurality of sample tubes may be used, and the number may be 2 or 4 or more.

  The shapes, dimensions, materials, and the like described below are examples, and can be appropriately changed according to the specifications of the adsorption characteristic measuring device.

  Hereinafter, in all the drawings, the same reference numerals are given to one or corresponding elements, and redundant description is omitted.

  FIG. 1 is a configuration diagram of the adsorption characteristic measuring device 30. FIG. 1 shows three sample tubes 10, 12, and 14, and samples 20, 22, and 24 accommodated therein, although they are not constituent elements of the adsorption characteristic measuring device 30. After attaching these three sample tubes 10, 12, and 14, the adsorption characteristic measuring device 30 can perform the adsorption characteristic measurement for the next sample in parallel while measuring the adsorption characteristic for one sample. It has a function that can.

  The adsorption characteristic measuring apparatus 30 includes a refrigerant container 34 filled with a refrigerant 32 for setting the temperature suitable for measuring the adsorption characteristics of the three sample tubes 10, 12, and 14, a helium gas source 36, An adsorbate gas source 38, a second adsorbate gas source 40, an exhaust pump 42, a piping unit 46 including a manifold 44, and a measurement control unit 100 are configured.

  The three sample tubes 10, 12, 14 and the three samples 20, 22, 24 have the same configuration except that the adsorption characteristic measurement process is performed separately. Continue to explain.

  The sample tube 10 is an elongate tube having an end opening at one end, and is a sample container in which the inner space at the bottom, which is the other end, serves as a storage portion that can store the sample 20. The end opening at one end of the sample tube 10 is connected to the helium gas source 36, the first adsorbate gas source 38, the second adsorbate gas source 40, or the exhaust pump 42 via the piping unit 46.

  As the sample tube 10, a glass test tube having a uniform outer diameter and inner diameter is used. An example of the dimensions of the sample tube 10 is an inner diameter of 1 cm and a length of 20 cm. Depending on the purpose of the measurement, a quartz test tube or a metal test vessel may be used as the sample tube. The shape may also be suitable for measurement purposes. For example, the end opening portion may be thin and the accommodating portion may be thick. The dimensions may also be suitable for measurement purposes. The three sample tubes 10, 12, and 14 may have different shapes, dimensions, and materials.

  The sample 20 is a powder that is an object of adsorption characteristic measurement. In order to evaluate the specific surface area and pore distribution of the powder, the adsorption characteristics of the powder to determine how much adsorbate is adsorbed are measured. Since the sample 20 is an object for measuring adsorption characteristics, it varies depending on the purpose of the measurement. The particle size of the powder may vary, and it may be a solid other than the powder, or the solid may be porous. The three samples 20, 22, and 24 may be different from each other or the same. The adsorbate is supplied from the first adsorbate gas source 38 or the second adsorbate gas source 40 via the piping 46. Hereinafter, the description will be continued assuming that the nitrogen gas from the first adsorbate gas source 38 is an adsorbate.

The refrigerant container 34 is a dewar for maintaining the sample tubes 10, 12, 14 at a predetermined temperature T _d by arranging the sample tubes 10, 12, 14 in the internal space and filling the periphery with the refrigerant 32. is there. The type of the refrigerant 32 is selected depending on the adsorbate, but when the adsorbate is nitrogen gas, the refrigerant 32 may be liquid nitrogen. In this case, the predetermined temperature T _d is 77K.

A helium gas source 36 indicated as He in FIG. 1 is a gas cylinder filled with helium gas for measuring the dead volume V _d of the sample tubes 10, 12, and 14. In measuring the dead volume when the adsorbate is nitrogen, it is necessary to use an inert substance that does not adsorb at the nitrogen adsorption temperature for the samples 20, 22 and 24, but helium gas is a gas suitable for that purpose. . The dead volume _Vd is measured using the method described in Patent Document 2, and details thereof will be described later.

  The first adsorbate gas source 38 is an adsorbate supply unit that supplies an adsorbate that is an object for measuring the adsorption characteristics of the samples 20, 22, and 24. Here, since the adsorbate is nitrogen gas, the first adsorbate gas source 38 is a nitrogen gas cylinder. The second adsorbate gas source 40 is a spare adsorbate supply unit, and is used, for example, when supplying an adsorbate different from the first adsorbate gas source 38.

  The exhaust pump 42 is an exhaust device for depressurizing any one of the sample tubes 10, 12, and 14 and the inside of the manifold 44. As the exhaust pump 42, a rotary pump can be used. Depending on the purpose of the adsorption characteristic measurement, a turbo molecular pump may be used and a rotary pump may be used as an auxiliary pump.

  The piping unit 46 is connected to the three sample tubes 10, 12, 14, the helium gas source 36, the first adsorbate gas source 38, the second adsorbate gas source 40, the exhaust pump 42, and the saturated vapor pressure tube 48 via the manifold 44. Are a plurality of pipes provided to connect the two to each other. The piping unit 46 is provided with a plurality of on-off valves 54, 64, 74, 82, 86, 90, 92, and 96 that operate under the control of the measurement control unit 100.

On / off valves 54, 64, and 74 are connected to the pipes provided between the three sample tubes 10, 12, and 14 and the manifold 44 in the pipe portion 46. In the case of the sample tube 10, the attachment portion 50 attached to the end opening of the sample tube 10 is one end side, the connection port provided in the manifold 44 is the other end side, and the open / close valve 54 is provided between the one end side and the other end side. Are connected in series to form a pipe for the sample tube 10. The pressure gauge 56 is a sample tube pressure detection unit that is connected to a pipe between the attachment unit 50 and the on-off valve 54 and detects the internal pressure P ₁ of the sample tube 10.

Similarly, an open / close valve 64 is connected in series between the attachment portion 60 attached to the end opening of the sample tube 12 and the manifold 44 to serve as a pipe for the sample tube 12. The pressure gauge 66 is a sample tube pressure detection unit that is connected to a pipe between the mounting portion 60 and the on-off valve 64 and detects the internal pressure P ₂ of the sample tube 12. In addition, an open / close valve 74 is connected in series between the attachment portion 70 attached to the end opening of the sample tube 14 and the manifold 44 to serve as a pipe for the sample tube 14. The pressure gauge 76 is a sample tube pressure detection unit that is connected to a pipe between the attachment unit 70 and the on-off valve 74 and detects the internal pressure P ₃ of the sample tube 14.

  In the piping portion 46, a flow rate adjusting valve 80 and an on-off valve 82 are connected in series between the helium gas source 36 and the manifold 44. Similarly, a flow rate adjustment valve 84 and an on-off valve 86 are connected in series between the first adsorbate gas source 38 and the manifold 44. Between the second adsorbate gas source 40 and the manifold 44, a flow rate adjustment valve 88 and an on-off valve 90 are connected in series. An on-off valve 92 is disposed between the exhaust pump 42 and the manifold 44.

The manifold 44 is a fluid conduit in which one ends of the on-off valves 54, 64, 74, 82, 86, 90, 92, and 96 are connected to each other. The pressure gauge 94 is a manifold pressure detection unit that detects the internal pressure P ₀ of the manifold 44. In FIG. 1, the manifold 44 is shown as a bent pipe, but a box-shaped container to which one end of the on-off valves 54, 64, 74, 82, 86, 90, 92, 96 is attached may be used. Good.

The pipe line of the manifold 44 is used as a space once introduced here when helium gas is supplied from the helium gas source 36 to any of the sample tubes 10, 12, 14 in order to measure the dead volume V _di. . Further, the pipe line of the manifold 44 is temporarily used when nitrogen gas as an adsorbate is supplied from the first adsorbate gas source 38 to any one of the sample tubes 10, 12, and 14 in order to measure adsorption characteristics. Used as a space to be introduced. That is, the volume of the conduit of the manifold 44 is the reference volume V _S during the helium gas supply for the measurement of the dead volume is the reference volume V _S during the nitrogen gas supply for the adsorption properties measured.

Since the manifold 44 defines a reference volume V _S when measuring the dead volume and measuring the adsorption characteristics, the piping unit 46 including the manifold 44 is accommodated in a temperature-adjusted bath and maintained at a predetermined reference temperature T _S. Is done. The temperature adjustment is necessary for the manifold 44 and the on-off valves 54, 64, 74, 82, 86, 90, 92, 96 and the pipes connecting between them. In some cases, the temperature adjustment valves 80, 84, 88 are temperature adjusted. You may leave the bus.

  The saturated vapor pressure tube 48 is an elongated tube having an end opening at one end, and a container having a bottom at the other end. An opening / closing valve 96 for the saturated steam pressure pipe is provided between the end opening of the saturated steam pressure pipe 48 and the manifold 44, and an end opening of the saturated steam pressure pipe 48 and the opening / closing valve 96 for the saturation steam pressure pipe are provided. A pressure gauge 98 for a saturated vapor pressure pipe is provided between them.

  The saturated vapor pressure tube 48 is used to actually measure the saturated vapor pressure of the adsorbate when excess adsorbate is accommodated and the saturated vapor pressure tube 48 is immersed in the refrigerant 32. Here, the adsorbate is nitrogen. In FIG. 1, the saturated vapor pressure tube 48 is disposed away from the sample tube 10, but actually, it is preferable that the saturated vapor pressure tube 48 be disposed at the center surrounded by the three sample tubes 10, 12, and 14. The end opening of the saturated vapor pressure pipe 48 is connected to the sample pipes 10, 12, 14, first and second adsorbate gas sources 38, 40, and an exhaust pump 42, which will be described later, via a pipe part 46. The saturated vapor pressure pipe 48 has an inner diameter of 2 mm and can be made of stainless steel.

  The measurement control unit 100 controls the opening / closing of the on-off valves 54, 64, 74, 82, 86, 90, 92, 96 of the piping unit 46, and uses the detected values of the pressure gauges 56, 66, 76, 94, 98. A control device having a function of measuring adsorption characteristics. The measurement control unit 100 can be configured by an appropriate computer.

The measurement control unit 100 includes a dead volume calculation procedure 102, an introduction processing procedure 104 for introducing the adsorbate into the reference volume V _S of the manifold 44, and the adsorbate introduced into the reference volume V _S as the sample tubes 10, 12, 14. And the adsorption amount calculation procedure 108 for calculating the adsorption amount for the samples 20, 22, and 24.

  Here, using one manifold 44, the introduction process procedure 104 and the supply process procedure 106 are executed as a set for the sample tube 10, and subsequently, the introduction process procedure 104 and the supply process procedure 106 are set as a set for the sample tube 12. The introduction process procedure 104 and the supply process procedure 106 are subsequently executed as a set for the sample tube 14. Since the introduction processing procedure 104 and the supply processing procedure 106 are the supply of the adsorbate from the first adsorbate gas source 38 to the manifold 44 and the supply of the adsorbate from the manifold 44 to the sample tubes 10, 12, 14. Finish in a short time. The amount of adsorbate supplied to the sample tubes 10, 12, and 14 is performed based on the pressure detected by one pressure gauge 94 provided in the manifold 44, and these pressure detections are performed within a short time. Can be done sequentially.

  On the other hand, the execution of the adsorption amount calculation procedure 108 requires a long time to complete since the adsorbate is sufficiently adsorbed on the samples 20, 22, and 24 to reach an equilibrium state. Accordingly, the adsorption amount calculation procedure 108 is executed in parallel using the pressure gauge 56 for the sample tube 10, the pressure gauge 66 for the sample tube 12, and the pressure gauge 76 for the sample tube 14. In this way, the adsorption characteristic measurement for the next sample can be performed in parallel while the adsorption characteristic measurement for one sample is performed using one adsorption characteristic measurement device 30.

  Such a function can be realized by executing software. Specifically, it can be realized by executing a multi-sample adsorption characteristic measurement program. Some of these functions may be executed by hardware.

  The operation of the above configuration, in particular, each function of the measurement control unit 100 will be described in detail with reference to FIGS. FIG. 2 is a flowchart showing an operation procedure for measuring the adsorption amount. FIG. 3 is a time chart showing the opening / closing timing of each on-off valve for the adsorption amount measurement and the change in the detected value of each pressure gauge.

2 and 3, so is for processing after the dead volume V _di for the sample tube 10, 12 is calculated, prior to these descriptions, describing calculation of dead volume V _di .

First, in order to calculate the dead volume V _di , helium gas is introduced into the reference volume V _S , the pressure is P _S , the temperature is T _S, and the helium gas introduced into the reference volume V _S is the temperature T _d . The pressure P _di when introduced into the sample tube 10 is obtained. From these values, the dead volume V _di can be obtained by using the relational expression P _S V _S = P _di (V _S + V _di ). Since the dead volume V _di calculation process is the same for any of the sample tubes 10, 12, and 14, the sample tube 10 will be described below as a representative example.

The dead volume V _d1 for the sample tube 10 refers to the volume of the sample tube 10 from the on-off valve 54. In general, a part of the sample tube 10 is cooled to a low temperature by the refrigerant 32 and kept at a temperature at which the adsorbate is adsorbed to the sample 20. However, the low temperature part and the room temperature part cannot be clearly separated and there is a temperature gradient. The dead volume referred to here is a volume calculated from a pressure decrease when the adsorbate of the manifold 44 is introduced into the sample tube 10, and the pressure decrease is the same if the adsorbate is not adsorbed. That is, the dead volume referred to here is an apparent volume when the sample tube 10 is at the same temperature as the manifold 44. This dead volume can be assumed to have the same apparent volume at the time of measurement by making the temperature environment of the sample tube 10 constant when calculating the adsorption amount.

In FIG. 1, in the initial state, the end opening of the sample tube 10 that accommodates the sample 20 is connected to the mounting portion 50, and the on-off valves 54, 64, 74, 82, 86, 90, 92, and 96 are all closed. It is in a state. The refrigerant container 34 is filled with the refrigerant 32, the temperature of the sample tube 10 is T _d , and the temperature of the manifold 44 is T _S. In this state, the on-off valve 54 and the on-off valve 92 are opened, and the exhaust pump 42 is operated. As a result, the manifold 44 and the inside of the sample tube 10 are sufficiently depressurized and become nearly vacuum. Thereafter, the on-off valve 54 and the on-off valve 92 are closed, and the operation of the exhaust pump 42 is stopped.

Next, the on-off valve 82 is opened, and helium gas is introduced from the helium gas source 36 into the manifold 44. The on-off valve 82 is closed at an appropriate time, and the pressure in the manifold 44 at that time is detected by the pressure gauge 94. Assuming that the detected pressure is P _S , the helium gas introduced into the manifold 44 is at the temperature T _S and the pressure P _S , and the volume is the reference volume V _S.

Next, the on-off valve 54 is opened, and the pressure in the sample tube 10 and the manifold 44 is detected by the pressure gauge 56 or the pressure gauge 94. Let the detected pressure be P _d1 . Since the temperature of the sample tube 10 is T _di and the helium gas is not adsorbed to the sample 20 even at a temperature lower than the nitrogen adsorption temperature, the helium gas introduced into the manifold 44 spreads over the manifold 44 and the sample tube 10. Therefore, the dead volume V _d1 for the sample tube 10 that accommodates the sample 20 from the opening / closing valve 54 is calculated using the relational expression P _S V _S = P _d1 (V _S + V _d1 ).

When the dead volume V _d1 is calculated, the on-off valve 92 is opened and the exhaust pump 42 is operated. As a result, the helium gas is discharged from the inside of the manifold 44 and the sample tube 10, and the pressure is sufficiently reduced to a state close to a vacuum. Thereafter, the on-off valve 54 and the on-off valve 92 are closed, and the operation of the exhaust pump 42 is stopped.

Similarly, the dead volume V _d2 for the sample tube 12 that houses the sample 22 and the dead volume V _d3 for the sample tube 14 that houses the sample 24 are calculated. The dead volume V _d1 , the dead volume V _d2 , and the dead volume V _d3 are not necessarily the same value. The dead volume is calculated by a dead volume calculation procedure 102 of the measurement control unit 100. In order to improve the accuracy of dead volume calculation, the dead volume is calculated several times and the average value can be used.

When the dead volume V _d1 , dead volume V _d2 , and dead volume V _d3 are calculated, the process for measuring the adsorption characteristics is performed according to the flowchart of FIG. 2 and the time chart of FIG.

FIG. 2 is a flowchart showing a procedure for measuring adsorption characteristics, and each procedure corresponds to each processing procedure of the multi-sample adsorption property measurement program. FIG. 3 is a time chart corresponding to FIG. The pressure P ₀ detected by the pressure gauge 94, the pressure P ₁ detected by the pressure gauge 56, the pressure P ₂ detected by the pressure gauge 66, and the pressure P ₃ detected by the pressure gauge 76 are taken. ing.

  In FIG. 2, S10, S26, and S28 indicate that the procedure is repeated when there are a plurality of sample tubes to be measured. In S10, a counter for counting repetitions is set to i = 1 to indicate the initial state. At this time, the on-off valves 54, 64, 74, 82, 86, 90, 92, and 96 are all closed, and the pressures detected by the pressure gauges 56, 66, 76, and 94 are all sufficiently reduced and close to vacuum. Pressure.

  Then, the processing for the sample tube 10 is started. First, introduction processing is performed (S12). This processing procedure is executed by the introduction processing procedure 104 of the measurement control unit 100. The introduction process is performed by switching the on-off valve 86 from the closed state to the open state and returning it to the closed state again after reaching the target pressure.

In FIG. 3, since the on-off valve 86 is changed from the closed state to the open state at time t ₁ , the introduction process is started at this time. When the on-off valve 86 is opened, nitrogen gas as an adsorbate is introduced into the manifold 44 from the first adsorbate gas source 38, and the internal pressure of the manifold 44 increases. FIG. 3 shows that the pressure P ₀ detected by the pressure gauge 94 has increased from a pressure close to vacuum to P _I1 ¹ . Thereafter, the opening and closing valve 86 is returned to the closed state at time t _2. The time t ₂ is the end of the introduction period (S14). Therefore, the period (t ₂ −t ₁ ) between time t ₁ and time t ₂ is the introduction period. In the introduction period, nitrogen gas to be supplied to the sample tube 10 is once introduced into the manifold 44 having the reference volume V _S. Since the pressure fluctuates immediately after the on-off valve 86 is changed from the open state to the closed state, it is preferable to detect the pressure by the pressure gauge 94 after a waiting time of several seconds. The internal pressure P _I1 ¹ of the manifold 44 detected during the introduction period is transmitted to the measurement control unit 100 and acquired (S16).

After time t _2, at an appropriate waiting time, the supply process is executed (S18). This processing procedure is executed by the supply processing procedure 106 of the measurement control unit 100. The supply process is a process in which the nitrogen gas introduced into the manifold 44 is transferred to the sample tube 10, and the on-off valve 54 is changed from the closed state to the open state, and is returned to the closed state again after an arbitrarily determined valve opening time. Done.

In FIG. 3, since the on-off valve 54 is opened from the closed state at a time t ₃ when an appropriate time has elapsed from the time t ₂ , the supply process is started at this time. When the on-off valve 54 is opened, the nitrogen gas sealed inside the manifold 44 is transferred from the manifold 44 to the sample tube 10, and the internal pressure of the manifold 44 decreases. At the same time, the internal pressure of the sample tube 12 increases. FIG. 3 shows a state in which the pressure P ₀ detected by the pressure gauge 94 decreases from P _I1 ¹ and the pressure P ₁ detected by the pressure gauge 56 increases from a pressure close to vacuum. Thereafter, the on-off valve 54 is returned to the closed state at time t ₄ . This time t ₄ is the end of the opening period (S20). Therefore, the period of (t ₄ −t ₃ ) between time t ₃ and time t ₄ is the valve opening period.

During the valve opening period, the nitrogen gas introduced into the manifold 44 is transferred to the sample tube 10, but since the internal pressure of the manifold 44 does not drop to a pressure close to the original vacuum, all of the nitrogen gas introduced into the manifold 44 is removed. Is not transferred to the sample tube 10. As an indication of the amount of nitrogen gas remaining in the manifold 44, the internal pressure P _I ^{1 *} of the manifold 44 at the end of the valve opening period is detected by the pressure gauge 94 and transmitted to the measurement control unit 100 for acquisition ( S21).

When the valve opening period ends, the on-off valve 54 is closed, so that the inside of the sample tube 10 is sealed, and adsorption of nitrogen gas to the sample 20 starts. Although the internal pressure of the sample tube 10 starts to decrease with the adsorption of the nitrogen gas, the adsorption proceeds slowly over time, so the pressure change is gentle. It takes a long time for nitrogen gas to be sufficiently adsorbed to the sample 20 and the internal pressure of the sample tube 10 to be in an equilibrium state, and whether the equilibrium state has been reached requires continuous monitoring of pressure changes. . Therefore, when the valve opening period ends, monitoring of the pressure P ₁ detected by the pressure gauge 56 starts (S22). The detected pressure P ₁ is transmitted to and acquired by the measurement control unit 100 and is stored in an appropriate storage device every time. The acquisition interval of the pressure P ₁ can be changed by software according to the characteristics of the sample 20. When the sample 20 is a substance with a high adsorption rate, the acquisition interval is shortened, and when the sample 20 is a substance with a low adsorption rate, the acquisition interval is lengthened.

Further, it is determined whether or not the pressure P ₁ detected by the pressure gauge 56 is significantly lower than the adsorption target equilibrium pressure P _t (S24). If significantly low, repeat the process again from the introduction process (S12) without waiting for the adsorption equilibrium to P _I acquired (S16), it performed Repeat together supply process (S18) to Pi monitoring (S22), measuring the equilibrium pressure can be brought close to the adsorption purpose equilibrium pressure P _t.

In FIG. 3, the introduction process is repeated from P _I1 ^{1 *} to P _I1 ^{2 *} and P _I1 ^{3 *,} and the on-off valve 54 is repeatedly opened and closed to monitor the internal pressure P ₁ of the sample tube 10. It is shown. This operation makes it possible to obtain the measurement points as desired or evenly, and to shorten the measurement time. Similarly, it is determined whether the adsorption amount change of the adsorption amount V _i for the sample 20 is greater than the adsorption target amount V _t (S23). If it is determined that the adsorption amount V _i is large, the above-described processing (S24) is performed. Can be skipped, and an even adsorption amount measurement interval can be maintained. In FIG. 3, the adsorption target introduction pressure P _t is reached by repeating the adsorbate introduction process three times for the sample 20 of the sample tube 10, and the sample 22 of the sample tube 12 and the sample 24 of the sample tube 14 are reached. It is shown to reach the adsorption purposes equilibrium pressure P _t by performing once adsorbate introduction treatment against.

Monitoring of P _1, since the pressure gauge 56 provided in the sample tube 10 in the closed state is performed for the pressure P ₁ to be detected to perform the opening and closing of the valve other than the on-off valve 54 in the independent pipe 46 from this be able to.

  Therefore, when there are a plurality of sample tubes to be measured, the count value i of the counter for counting repetition is incremented by 1 and set to i = i + 1 (S26). Since i = 1 in S10, i = i + 1 = 2. Next, it is determined whether or not the new i exceeds N, which is the limit of the number of repetitions (S28). Here, since the adsorption characteristics are measured for the three sample tubes 10, 12, and 14, N = 3. Since i = 2, the determination in S28 is negative and the process returns to S12.

When i = i + 1 = 2 and the process returns to S12, the process described above is repeated for the sample tube 12 this time. With reference to FIG 3, since the introduction process and supply process is completed for the sample tube 10 at time t _12, the introduction process for the sample tube 12 from the time t ₁₃ elapses appropriate time from the time t ₁₂ is started.

That is, at time t ₁₃ , the on-off valve 86 is changed from the closed state to the open state, and nitrogen gas is introduced from the first adsorbate gas source 38 into the manifold 44. This is the start of the introduction process for the sample tube 12 (S12). At time t ₁₄ , the introduction period ends (S 14), and at time t ₁₄ , the on-off valve 86 is returned to the closed state, and the pressure P _I2 ¹ detected by the pressure gauge 94 is acquired and transmitted to the measurement control unit 100 ( S16). The introduction period (t ₁₄ -t ₁₃ ) for the sample tube 12 may be the same as or different from the introduction period (t ₂ -t ₁ ) performed for the sample tube 10. The pressure P _I2 detected by the pressure gauge 94 for the sample tube 12 is not necessarily the same as the pressure P _I1 detected by the pressure gauge 94 for the sample tube 10.

Off valve 64 at the time t ₁₅ elapses appropriate time from the time t ₁₄ is from the closed state to the open state, the nitrogen gas from the manifold 44 is transferred to the sample tube 12. This is the start of the supply process for the sample tube 12 (S18). At time t ₁₆ , the valve opening period ends (S 20), the on-off valve 64 is returned to the closed state, and the pressure P _I2 ^{1 *} detected by the pressure gauge 94 is acquired and transmitted to the measurement control unit 100 (S 22). . The valve opening period (t ₁₆ -t ₁₅ ) for the sample tube 12 may be the same as or different from the valve opening period (t ₄ -t ₃ ) performed for the sample tube 10. The pressure P _I2 ^{1 *} detected by the pressure gauge 94 for the sample tube 12 is not necessarily the same value as the pressure P _I1 ^{1 *} detected by the pressure gauge 94 for the sample tube 10. Then, monitoring of the pressure P ₂ detected by the pressure gauge 66 of the sample tube 12 is started (S24).

  Therefore, the count value i of the counter for counting repetitions is incremented by 1 and set to i = i + 1 = 3 (S26), and it is determined whether or not the new i = 3 exceeds N = 3 which is the limit of the number of repetitions. (S28). Since the determination in S28 is negative, the process returns to S12 again.

When i = i + 1 = 3 and the process returns to S12, the process described above is repeated for the sample tube 14 this time. With reference to FIG. 3, the supply process and implementation process for the sample tube 12 is terminated at time t _16, the introduction process for the sample tube 14 from the time t ₁₇ has passed the appropriate time from the time t ₁₆ is started.

That is, at time t ₁₇ , the on-off valve 86 is changed from the closed state to the open state, and nitrogen gas is introduced from the first adsorbate gas source 38 into the manifold 44. This is the start of the introduction process for the sample tube 14 (S12). Introduction period ends at time t ₁₈ and (S14), on-off valve 86 is returned to the closed state, the pressure gauge 94 is transmitted to the pressure P _I3 ^{1 *} measurement control section 100 is acquired to detect (S16). The introduction period (t ₁₈ -t ₁₇ ) for the sample tube 14 is the introduction period (t ₂ -t ₁ ) performed for the sample tube 10 and the introduction period (t ₁₄ -t ₁₃ ) performed for the sample tube 12. It may be the same as or different from. The pressure P _I3 detected by the pressure gauge 94 in the case of the sample tube 14 is not necessarily the same value as the pressures P _I1 and P _I2 detected by the pressure gauge 94 in the case of the sample tubes 10 and 12.

Off valve 74 at time t ₁₉ the appropriate time has elapsed from the time t ₁₈ is from the closed state to the open state, the nitrogen gas from the manifold 44 is transferred to the sample tube 14. This is the start of the supply process for the sample tube 14 (S18). Valve opening period ends at time t ₂₀ and (S20), on-off valve 74 is returned to the closed state, the pressure gauge 94 is transmitted to the pressure P _I3 ^{1 *} measurement control section 100 is acquired to detect (S22) . The valve opening period (t ₂₀ -t ₁₉ ) for the sample tube 14 is the valve opening period (t ₄ -t ₃ ) performed for the sample tube 10 and the valve opening period (t ₁₆ − for the sample tube 12). It may be the same as t ₁₅ ) or may be different. The pressure P _I3 ^{1 *} detected by the pressure gauge 94 for the sample tube 14 is not necessarily the same value as the pressures P _I1 ^{1 *} and P _I2 ^{1 *} detected by the pressure gauge 94 for the sample tubes 10 and 12. Then, monitoring of the pressure P ₃ detected by the pressure gauge 76 of the sample tube 14 is started (S24).

  Therefore, the count value i of the counter for counting repetitions is incremented by 1 and set to i = i + 1 = 4 (S26), and it is determined whether or not the new i = 4 exceeds N = 3 which is the limit of the number of repetitions. (S28). Since the determination in S28 is affirmative, the process does not return to S12, and the adsorbate introduction process for the manifold 44 ends.

Monitoring the change in the pressure gauge 56,66,76 of the sample tube 10, 12, 14 from the time t _20, when the pressure change is below a certain reference value, ie an adsorption equilibrium was reached (S29), the equilibrium pressure P ₁ ^* , P ₂ ^* , P ₃ ^* are acquired (S30), and the amount of adsorption is calculated (S36).

  In this way, using one manifold 44, the adsorbate is sequentially supplied to each of the plurality of sample tubes with the total period of the introduction period and the valve opening period as a repeating unit.

  From the second point onward, it is preferable to sequentially enter the nitrogen gas introduction process from the one in the adsorption equilibrium state. In this case, the measurement does not necessarily have to be performed in the order of the sample tubes 10, 12, and 14, and the entire measurement time can be shortened by sequentially shifting to the next measurement point from the sample that has been equilibrated.

During this time, the sample tubes 10, 12, and 14 are continuously monitored for the pressures P ₁ , P ₂ , and P ₃ detected by the pressure gauges 56, 66, and 76, respectively. Then, whether the adsorption of nitrogen gas to the sample 20, 22 and 24 were sufficiently, the pressure drop P _1, P _2, P ₃ is determined based on whether equilibrium is reached.

逐時monitoring of pressure P _1, P _2, P ₃ is performed by acquiring at a predetermined acquisition interval the pressure P _1, P _2, P ₃ to the pressure gauge 56,66,76 is detected. Acquisition of the pressure P _1, P _2, P _3, the three at the same time the pressure P _1, the P _2, P ₃ can be simultaneously acquired. For example, assuming that the acquisition interval is 10 minutes, the pressures P ₁ , P ₂ , and P ₃ are simultaneously acquired every 10 minutes. When the adsorption characteristics of the samples 20, 22 and 24 are significantly different, the acquisition intervals of P ₁ , P ₂ and P ₃ can be made different from each other. For example, the pressure acquisition interval is shortened for a sample with a high adsorption rate, and the pressure acquisition interval is increased for a sample with a low adsorption rate.

Whether or not the decrease in the pressures P ₁ , P ₂ , and P ₃ has reached an equilibrium state (S 29) can be determined based on whether or not the change in the pressure value during the pressure acquisition interval has become a predetermined range or less. For example, when the pressure acquisition interval is 10 minutes and the pressure acquisition interval is 10 minutes, the equilibrium state can be obtained when the pressure change rate in the 10 minutes is 1% or less. The determination interval and the rate of change in pressure used to determine whether or not the equilibrium state has been reached are examples, and may be appropriately changed according to the characteristics of the samples 20, 22, and 24.

FIG. 3 shows that for the sample 20 of the sample tube 10, the drop in the pressure P ₁ detected by the pressure gauge 56 becomes an equilibrium state and becomes P ₁ ^{* at} time t ₂₁ . Similarly, with respect to the sample 22 of the sample tube 12, it is indicated that the drop in the pressure P ₂ detected by the pressure gauge 66 becomes an equilibrium state and becomes P ₂ ^{* at} time t ₂₂ . For the sample 24 of the sample tube 14, it is shown that the drop in the pressure P ₃ detected by the pressure gauge 76 becomes an equilibrium state and becomes P ₃ ^{* at} time t ₂₃ . In FIG. 3, time t ₂₁ , time t ₂₂ , and time t ₂₃ are in this order, and the adsorption characteristic measurement of the sample 20 ends first, and then the adsorption characteristic measurement of the sample 22 ends. Finally, the measurement of the adsorption characteristics of the sample 24 is to be completed, but this order may be changed depending on the characteristics of the samples 20, 22, and 24.

Returning to FIG. 2, the pressures P ₁ ^* , P ₂ ^* , and P ₃ ^* in the equilibrium state are transmitted to the measurement control unit 100 and acquired (S30). Here, P _I1 acquired in _{S16, P I2, P I3,} S21 P obtained by ^{_{I1 *, P I2 *, P}} I3 *, P 1 acquired in ^{_{S30 *, P 2 *, P}} 3 * Based on the above, the adsorption amounts of the samples 20, 22, and 24 are calculated. The value of P _Ii ^n, n in P _Ii ^{n *,} there is shown a number of repetitions of introduction and supply process, wherein showed ^{_{P I1 1, P I1 2,}} P I1 3 as P _I1. Also, P _I2 ¹ is P _I2 and P _I3 ¹ is P _I3 .

Since the calculation procedures for the adsorption amounts of the samples 20, 22, and 24 are the same, the sample 20 will be described as a representative. The temperature of the manifold 44 is T _S , the volume is V _S , the temperature of the sample tube 10 in which the sample 20 is accommodated is T _{d, and the} dead volume is V _d1. The introduction amount Δn ₁ of the introduced adsorbate is calculated as Δn ₁ = (V _S / RT _S ) × (P _I1 −P _I1 ^* ) (S32). Next, the remaining amount of adsorbate Δn _d1 remaining in the dead volume V _d1 of the sample tube 10 is calculated as Δn _d1 = (V _d1 / RT _d ) × P ₁ ^* (S34).

Further, when nitrogen gas is introduced a plurality of times in order to measure the adsorption equilibrium pressure at an arbitrary pressure, the temperature of the manifold 44 is T _S and the volume is V _S. Using the gas constant R and the temperature of the tube 10 as T _{d and the} dead volume as V _d1 , the introduced amount Δn ₁ of nitrogen gas introduced into the sample tube 10 is expressed as Δn ₁ = (V _S / RT _S ) XΣ (P _I1 ⁿ −P _I1 ^{n *} ), and the remaining nitrogen gas amount Δn _d1 remaining in the dead volume of the sample tube 10 is calculated as Δn _d1 = (V _d1 / RT _S ) × P ₁ ^* The amount of nitrogen gas V ₁ adsorbed on the sample 20 inside the sample tube 10 is calculated as V ₁ = (Δn ₁ −Δn _d1 ).

In this way, when the introduction amount Δn _{1 of} nitrogen gas introduced into the sample tube 10 and the remaining nitrogen gas amount Δn _d1 remaining in the dead volume V _d1 of the sample tube 10 are obtained, the inside of the sample tube 10 is determined. The amount V _{1 of} nitrogen gas adsorbed on the sample 20 is calculated by V ₁ = (Δn ₁ −Δn _d1 ) (S36). This procedure is executed by the adsorption amount calculation procedure 108 of the measurement control unit 100.

The adsorption amount of the sample 22 is similarly calculated using the dead volumes V _d2 , P _I2 , P _I2 ^* , and P ₂ ^* of the sample tube 12. The adsorption amount of the sample 24 is similarly calculated using the dead volumes V _d3 , P _I3 , P _I3 ^* , P ₃ ^* of the sample tube 14. The dead volume V _di is not necessarily the same value in the sample tube 10 containing the sample 20, the sample tube 12 containing the sample 22, and the sample tube 14 containing the sample 24, and P _Ii and P _Ii ^* are not necessarily the same. 12 and 14 are not necessarily the same value.

  As described above, the adsorption characteristic measuring apparatus 30 repeats each sample tube 10, with the total period of the introduction period for introducing the adsorbate into the manifold 44 and the valve opening period for supplying the adsorbate from the manifold 44 to the sample tube as a repeating unit. Adsorbate is sequentially supplied to each of 12 and 14. Since the introduction period and the valve opening period are times for transferring the adsorbate, a short time is required. After the adsorbate is sequentially supplied to the sample tubes 10, 12, and 14, the sample tubes 10, 12, and 14 are subjected to before and after adsorption. The pressure change ΔP is measured. Since each of the sample tubes 10, 12, and 14 is independently provided with the pressure gauges 56, 66, and 76, ΔP can be measured in parallel even if time is required. In this way, the adsorption characteristic measurement for the next sample can be performed while the adsorption characteristic measurement for one sample is performed using one adsorption characteristic measurement device 30.

  10, 12, 14 Sample tube, 20, 22, 24 Sample, 30 Adsorption characteristic measuring device, 32 Refrigerant, 34 Refrigerant container, 36 Helium gas source, 38 First adsorbate gas source, 40 Second adsorbate gas source, 42 Exhaust pump, 44 manifold, 46 piping section, 48 saturated vapor pressure pipe, 50, 60, 70 mounting section, 80, 84, 88 flow control valve, 54, 64, 74, 82, 86, 90, 92, 96 on-off valve, 56, 66, 76, 94, 98 Pressure gauge, 100 measurement control unit, 102 dead volume calculation procedure, 104 introduction processing procedure, 106 supply processing procedure, 108 adsorption amount calculation procedure.

Claims (4)

An adsorption characteristic measuring device that measures adsorption characteristics by supplying a predetermined adsorbate to a plurality of samples accommodated in each of a plurality of sample tubes,
A plurality of attachment portions provided in each of the openings of the plurality of sample tubes;
An adsorbate supply unit for supplying adsorbate;
A manifold connected to each of the plurality of mounting parts via an on-off valve for the sample tube, and via an on-off valve for the adsorbate supply part and the adsorbate;
A manifold pressure gauge that detects the pressure of the manifold,
A plurality of sample tube pressure gauges that independently detect the internal pressures of the plurality of sample tubes;
A measurement controller;
With
The measurement control unit
An introduction processing procedure for introducing the adsorbate into the manifold in an open state for an introduction period arbitrarily determined from the closed state while the all open / close valves for the plurality of sample tubes are closed,
After returning the on / off valve for the adsorbate to the closed state, for any one of the plurality of sample tubes, the open / close valve for the sample tube is opened for a predetermined opening period from the closed state. A supply processing procedure for supplying adsorbate to a sample contained in a sample tube;
Repeatedly, the adsorbate is sequentially supplied to each of the plurality of sample tubes, with the total period of the introduction period and the valve opening period as a repeating unit,
An adsorption characteristic measuring apparatus for measuring adsorption characteristics of each sample tube supplied with adsorbate based on a manifold pressure and an internal pressure of each sample tube. In the adsorption characteristic measuring device according to claim 1,
The measurement control unit
When the adsorbate is supplied to the manifold when the adsorbate on / off valve is in the open state for a predetermined introduction period from the closed state while all of the plurality of sample tube on / off valves are closed, the manifold at the end of the introduction period Get the pressure as P _Ii ,
After returning the on / off valve for the adsorbate to the closed state, any one of the plurality of sample tubes is used as a measurement target sample tube, and the on / off valve for the measurement target sample tube is opened from the closed state for a predetermined valve opening period. As the pressure of the manifold at the end of the valve opening period when adsorbate is supplied to the sample accommodated in the sample tube to be measured as P _Ii ^* ,
When the open / close valve for the sample tube to be measured is returned to the closed state after the valve opening period ends, and the time change of the pressure detected by the sample tube pressure detector corresponding to the sample tube to be measured is monitored, and the pressure drop is in an equilibrium state The internal pressure of the sample tube to be measured is acquired as P _i ^* ,
The temperature of the manifold is T _S , the volume is V _S , the temperature of the sample tube to be measured is T _{d, the} dead volume is V _di , and the gas constant R is used to determine the adsorbate introduced into the sample tube to be measured. The introduction amount Δn _i is calculated as Δn _i = (V _S / RT _S ) × (P _Ii −P _Ii ^* ), and the remaining amount of adsorbate Δn _di remaining in the dead volume of the sample tube to be measured is Δn _di = ( V _di / RT _s ) × P _i ^* , and the amount of adsorbate V _i adsorbed to the sample inside the sample tube to be measured is obtained by V _i = (Δn _i −Δn _di ). Characteristic measuring device. In the adsorption characteristic measuring device according to claim 2,
An adsorption characteristic measuring apparatus for obtaining a dead volume V _di in advance for a plurality of sample tubes. In the adsorption characteristic measuring device according to claim 1,
An adsorption characteristic measuring device that measures adsorption equilibrium pressure at a predetermined pressure,
The temperature of the manifold is T _S , the volume is V _S , the temperature of the sample tube to be measured is T _{d, the} dead volume is V _di , and the gas constant R is used to determine the adsorbate introduced into the sample tube to be measured. the introduction amount _{Δn i, Δn i = (V} S / RT S) × Σ (P Ii n -P Ii n *) is calculated as the adsorbate remaining [Delta] n _di remaining dead volume of the measurement object sample tube [Delta] n _It is calculated as _di = (V _di / RT _S ) × P _i ^* , and the amount V _{i of} adsorbate adsorbed on the sample inside the sample tube to be measured is obtained by V _i = (Δn _i −Δn _di ). Adsorption characteristic measuring device.

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