JPH0361844A - Measuring apparatus for reaction of gas when temperature is increased - Google Patents

Abstract

PURPOSE:To exclude the effects of the fluctuations of pressure and atmospheric pressure in measuring guides due to rapid reactions by further providing a back pressure regulating valve in an apparatus for measuring reaction of gas at the time of temperature increase wherein the flow rate and the pressure of the reaction gas are adjusted with a flow rate control device comprising a pressure reducing valve and a flow meter. CONSTITUTION:A heat conductivity detector 1 and a molecular sieving trap 9 are arranged in a constant temperature oven 11. A back pressure regulating valve 10 is provided at the downstream of the detector 1. The data of a gas which is sent into a detecting system from a detected gas selecting valve RT2 are sent into a mass analyzer 7. The gas passes through an ultraviolet bypass valve, and in some cases, through an ultraviolet ray spectrophotometer 8. The gas is sent into the detector 1 through the molecular sieving trap 9 which is provided in the constant temperature oven 11. The trap 9 collects H2O, H2S, CO2 and the like contained in the generated gas. The gas from the detector 1 is treated in a gas cleaner GC through an output pressure meter G5 and the back pressure regulating valve 10 and exhausted through an exhaust port VT2. Therefore, when a reaction gas selecting valve RT1 and the detected gas selecting valve RT2 are suitably switched, the change after the treatment in a reactor 4 can be found with the analyzer 7 and the spectrophotometer 8.

Description

Detailed Description of the Invention [Industrial Application Field 1] The present invention is an elevation system that enables stable and highly accurate measurement without being affected by pressure changes and temperature changes outside the device, reaction gas heat, etc. This invention relates to a warm gas reaction measuring device.

[Prior art 1] Oxidation, reduction, and sulfidation are extremely important treatments in research on metal-containing catalysts, inorganic compounds, and the like.

As a measurement method to understand the dynamic changes in these processes, temperature-programmed gas reaction methods, such as temperature-programmed reduction reactions (TPR), are used.
erasure programmed reduce
ion), temperature-programmed oxidation reaction (TPO: temperature
ature programmed oxidation
n) and temperature-programmed sulfurization reaction (TPS)
ure programmed sulfiding)
is being carried out.

As an apparatus for a heated gas reaction, for example, an apparatus as shown in FIG. 7 is known [N, W, Hurst, etc., C
atal, Rev., 24, 233 (1985)
: P, Arnoldy et al., J, Catal, 92
35 (1985)], for example, temperature programmed reduction reaction (TPR) or temperature programmed sulfidation reaction ('
rps), pass hydrogen gas through the thermal conductivity detector 1 before and after the reaction, measure the difference in thermal conductivity between the hydrogen gas before and after the reaction, and determine the amount of hydrogen gas consumed from the difference. can do. Further, the type and amount of reaction products can be investigated using a mass spectrometer 7 and an ultraviolet spectrophotometer 8 provided downstream of the reactor 4. Temperature-programmed sulfidation reaction ('rp
In the case of s), hydrogen gas diluted with a carrier gas (for example, argon gas) is sent to the thermal conductivity detector 1 via a flow rate controller 3 (usually consisting of a pressure reducing valve and a flow meter). and subsequently to reactor 4.

On the other hand, hydrogen sulfide gas diluted with a carrier gas (for example, argon gas) is sent from another inlet 2a to a reactor 4 via a flow rate controller 3a, where these gases come into contact with the test compound 5. to cause a sulfurization reaction. The reactor 4 is located within an oven 6 which is connected to a temperature programmer (not shown) which controls the temperature of the oven 6.The sulfurized gas exits the reactor 4 and is transferred to a mass spectrometer. The necessary data is sent to the ultraviolet spectrophotometer 7 and the ultraviolet spectrophotometer 8, and then sent again to the thermal conductivity detector 1 via the molecular sieve trap 9.

[Problem to be Solved by the Invention 1] When investigating a heated gas reaction, it is important to control the flow rate of the reaction gas and the pressure within the measuring device. As mentioned above, in conventional heated gas reaction measurement devices, a flow rate control device consisting of a pressure reducing valve and a flow meter was installed at the reaction gas inlet to control the gas flow rate and pressure, but this was not sufficient. . In other words, there was a problem that the baseline during measurement changed due to changes in atmospheric pressure (pressure inside the laboratory) or pressure inside the reactor, and the sensitivity was not constant. In order to selectively detect the increase and decrease of hydrogen in the temperature sulfurization reaction ('RPS) and the increase and decrease of oxygen in the temperature programmed oxidation reaction, the thermal conductivity detector and molecules that make up the detection part of the measuring device are used. Temperature control of the sieve trap is also important, and it was found that this control directly affects the sensitivity and zero point stability.These changes in the external environment and the effects of pressure and heat within the measurement system are especially important when controlling the sample volume. This was noticeable when the sensitivity of the detector was high, or when the amount of sample was large and the reaction occurred rapidly.

Therefore, it is an object of the present invention to achieve stable and highly accurate processing without being affected by changes in external conditions such as atmospheric pressure and temperature, or changes in the pressure inside the reactor or the heat of the reaction gas. The object of the present invention is to provide a heated gas reaction measuring device that can perform measurements.

[Means for Solving the Problems 1] According to the present invention, the above object is to provide an elevator having a reaction gas supply device, a reactor connected to the reactor, and a gas component measuring device connected to the outlet of the reactor. In the hot gas reaction measuring device, a thermal conductivity detector constituting the gas component measuring device and a separator located upstream of the thermal conductivity detector are placed under the control of a temperature control device, and the gas This can be achieved by a heated gas reaction measuring device characterized by arranging a back pressure valve downstream of the component measuring device.

That is, in contrast to the conventional heated gas reaction measurement apparatus, in which the flow rate and pressure of the reaction gas were adjusted by a flow rate control device consisting of a pressure reducing valve and a flow meter, according to the present invention, the above-mentioned In addition to the flow rate control device, by providing a back pressure valve, it virtually eliminates the influence of system pressure fluctuations due to sudden reactions within the measurement system and atmospheric pressure fluctuations, and maintains a stable baseline during measurement. At the same time, the thermal conductivity detector constituting the gas component measuring device and the separator located upstream of the thermal conductivity detector are placed under the control of a temperature control device (for example, in a thermostatic oven). This arrangement makes it possible to substantially eliminate the effects of fluctuations in system temperature and atmospheric temperature.

Hereinafter, the present invention will be explained in more detail with reference to the drawings.

FIG. 1 is a schematic diagram illustrating a state in which the conventional measuring device shown in FIG. 7 is provided with a back pressure valve and a temperature control device (for example, a thermostat) according to the present invention.

As shown in FIG.
A back pressure valve 10 is provided downstream of.

A specific embodiment of the temperature programmed sulfidation reaction ('rps) measuring device according to the present invention is shown in FIG.

As shown in FIG. 2, hydrogen gas/argon gas is supplied from the inlet E1 to the input pressure control valve V1. It is sent to the reaction gas selection valve RTI via the input pressure gauge 01, the if elementary trap T1, the mass flow controller MCI, and the thermal conductivity detector 1. In addition, hydrogen sulfide gas/argon gas is supplied to another inlet E.
2 to input pressure control valve v2, input pressure gauge 02, trap T
2, and is sent together with the hydrogen gas/argon gas to the reaction gas selection valve RTI via the mass flow controller MC2. Furthermore, the gas selected by the gas selection valve RV (nitrogen gas, air or argon gas) is
Input pressure control valve V3, input pressure gauge 03, gas flow control valve ■4
1. Then, it is also sent to the reaction gas selection valve RTI via the flow meter G4.

The reaction gas selection valve RTI has two inlets and two outlets, and the gas from each inlet is transferred to the reactor 4 or the detection gas selection valve RT2.
Guide you to one of the following. Reactor 4 is equipped with a temperature programmer
Temperature control can be carried out by an oven 6 connected to (not shown). The detection gas selection valve RT2 also has two inlets and two outlets, and allows each gas entering from the reaction gas selection valve RTI and the reactor 4 to be passed through the detection system or (via the output pressure needle G6 and output pressure control valve V5). >Guided to either exhaust port VTI.The gas sent to the detection system from the detection gas selection valve RT2 sends data to the mass spectrometer 7, and then is passed through the ultraviolet spectrophotometer 8 by the ultraviolet bypass valve as the case may be. ,
The zero-molecule sieve trap 9, which reaches the thermal conductivity detector 1 via the molecular sieve trap 9 arranged in the thermostatic chamber 11, collects HO, H3, ■, etc. contained in the generated gas.

The gas exiting the thermal conductivity detector 2 2 2 further passes through an output pressure needle 05 and a back pressure valve 10, is treated in a gas cleaner box, and then is discharged from an exhaust port Vr2. Therefore, by appropriately switching the reaction gas selection valve RTI and the detection gas selection valve RT2, the inlet E
The hydrogen/argon gas from 1 can be passed through the thermal conductivity detector 1 before and after the reaction in the reactor 4 to measure the change in its thermal conductivity. Also, hydrogen/hydrogen sulfide/
The changes after treatment of the argon gas mixture in the reactor 4 can be measured with a mass spectrometer 7 and an ultraviolet spectrophotometer 8.

In the measuring device of the present invention, the thermal conductivity detector and the molecular sieve trap may be placed in the same thermostatic oven or in different thermostatic ovens.The operating temperature range of the thermostatic oven is 30℃~
Using a device with a temperature of 400°C, the temperature at the time of measurement was set to 30 to 8
0℃, and the temperature during trap heating regeneration to 100-40℃.
The temperature is set at 0°C, and the temperature is controlled within ±2°C, preferably within ±1°C. The thermal conductivity detector is desirably set at room temperature or higher, and is generally set at room temperature to 100°C. The molecular sieve trap may be set at a temperature below room temperature, and the trap effect is better at lower temperatures.

The back pressure valve adjusts the pressure within the system from downstream of the mask low control cooler (MCI and MC2 in FIG. 2) to the back pressure valve. The adjusted pressure varies depending on the type of reaction to be carried out, but is generally 0.05 to 3 kgf/cm2.

In addition, temperature programmed reduction reaction (TPR) was carried out using the measuring device shown in Figure 2.
), generally only inlet E1 is used to introduce hydrogen gas and argon gas.

Further, when performing a temperature programmed sulfurization reaction ("rps"), generally hydrogen gas and argon gas are introduced from the inlet E1, and hydrogen sulfide gas and argon gas are introduced from the inlet E2.

[Example 1] Hereinafter, the present invention will be explained in more detail with reference to Examples, but these are not intended to limit the scope of the present invention.

In the following examples, temperature-programmed sulfurization reaction (TPS) and temperature-programmed reduction reaction (TPR) were performed using the measuring device shown in FIG.
I did this. The equipment and setting conditions used are as follows.

(a) Input pressure control valves ■1 and ■2: RP122 manufactured by Okura Riken Set pressure 0.05 to 6 kg (maximum 10 kg) Pressure fluctuation within 0.5% (port) Back pressure valves 1 and ■5: manufactured by Okura Riken RV-236 Setting pressure 0 to Ikg/cm2 (Reproducibility ±0.002kg
/cm2) (c) Mass flow controllers MCI and MC2: FvlF5041A83F0.4-20Sα manufactured by Okura Riken:
M (cc/m1n) (Flow rate variation ±0.25%) (2> Detector 1: Thermal conductivity detector (Okura Riken 802T) (e) Trap (e) Molecular sieve SA Temperature operating temperature range of constant temperature chamber =30~400°C Temperature during TPS/rPR measurement: 30~8o0C During trap heating regeneration: ioo~400'C Example Thermal conductivity detector (TC) in elevated temperature reduction reaction (TPR)
D: thermal conductivity
The baseline stability of the test vector was investigated. The amount of current of the thermal conductivity detector 1 was about 100 mA, and the set temperature was 60'C. The circulating gas is H2 (65%)/
Ar gas was used at 20 m1/min and 0.1 kg/cm2. The set temperature of the trap (molecular sieve 5A) was 30°C. The results are shown in Figure 3. As is not clear from Figure 3, standard measurement conditions (Attenuati
on-4), the baseline was sufficiently stable.

Furthermore, even when the sensitivity was increased to 4 times higher (Attenuation-1), a baseline sufficient for practical use was shown.

Under the same conditions as Example 1, vanadium pentoxide (V2O,)7.
A temperature programmed reduction reaction (TPR) of 63 mg was carried out and the results obtained under standard measurement conditions (Attenuation=4) are shown in FIG. In Figure 4, curve T shows the temperature change, and curve H shows the hydrogen consumption, vanadium pentoxide (V2
7.63 mg of vanadium sesquioxide (V2O,)
The amount of hydrogen consumed to reduce the amount to 83.9 μmol
However, it was possible to measure with good sensitivity using a stable baseline.

Translucent 1 Vanadium pentoxide (VO, ), manganese trioxide (MoO
2), and temperature-programmed reduction reaction of iron sesquioxide (Fe20.) (
T1)R) was conducted to examine the relationship between the signal intensity of the thermal conductivity detector and the amount of hydrogen consumed. The results are shown in Figure 5, and linearity was confirmed over a wide range. This indicates the stability of the thermal conductivity detector.

Temperature-programmed sulfurization (TPS) was carried out using 30.14 mg of permeable iron sesquioxide (α-Fe20.). The current amount of thermal conductivity detector 1 is approximately 100mA, and the set temperature is 40"C.
Met. The circulating gases were H2 (65%>h mixed gas at 6.7ml/ml and O, 1kg/cm2), and H3 (5.5%>h mixed gas at 11.3ml/min).
and O, Ikg/am2. The set temperature of the trap (molecular sieve 5A) was 40°C. Hydrogen gas consumption was measured independently with a thermal conductivity detector, and hydrogen sulfide gas consumption was measured with an ultraviolet spectrophotometer. 6th result
As shown in the figure. In FIG. 6, the curve T shows the temperature change;
Curve H shows hydrogen consumption and curve S shows hydrogen sulfide consumption.

The mountain-shaped portion of curve H means that hydrogen consumption is large, and the valley-shaped portion of curve S means that hydrogen sulfide consumption is large. As is clear from FIG. 6, the consumption of hydrogen gas and hydrogen sulfide gas can be measured independently using a thermal conductivity detector and an ultraviolet spectrophotometer.

[Effect of the invention 1] The heated gas reaction measuring device of the present invention is equipped with a back pressure valve in addition to the pressure reducing valve and flow meter in the conventional measuring device, so that it is possible to prevent atmospheric pressure fluctuations or rapid reactions within the system. A stable baseline can be obtained by substantially eliminating the influence of pressure fluctuations. Furthermore, it is convenient for performing leak tests and high pressure measurements within the system. Furthermore, in the measuring device of the present invention, since the thermal conductivity detector 1 and the molecular sieve trap 9 are installed in the thermostatic chamber 11, the influence of atmospheric temperature fluctuations and reaction gas heat can be substantially eliminated. Furthermore, the trap can be easily regenerated by heating. The heated gas reaction measuring device of the present invention is useful for manufacturing and managing catalysts and inorganic oxides.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram schematically showing the principle of the heated gas reaction measuring device of the present invention, FIG. 2 is a system diagram of an embodiment of the measuring device of the present invention, and FIG. Figure 4 is a graph showing the baseline stability when temperature programmed reduction reaction (TPR) is carried out with the measurement device, and shows the hydrogen consumption when temperature programmed reduction reaction (TPR) is carried out with the measurement device of the present invention. Graph showing,
Figure 5 shows temperature programmed reduction reaction (TPR) using the measuring device of the present invention.
Figure 6 is a graph showing the relationship between the signal intensity of the thermal conductivity detector and the amount of hydrogen consumed when the measurement device of the present invention is used to carry out the hydrogen and A graph showing the amount of hydrogen sulfide consumed, and Figure 7,
FIG. 2 is an explanatory diagram schematically showing the principle of a conventional heated gas reaction measuring device. 1... Thermal conductivity detector: 3... Flow rate control device: 4.
...Reactor 29...Molecular sieve trap: 10...
Back pressure valve: 11. ... Constant temperature bath.

Claims (1)

[Claims] (1) In a heated gas reaction measuring device having a reaction gas supply device, a reactor connected to the reactor, and a gas component measuring device connected to the outlet of the reactor, the gas component measuring device is configured as described above. A thermal conductivity detector and a separator located upstream of the thermal conductivity detector are placed under the control of a temperature control device, and a back pressure valve is disposed downstream of the gas component measuring device. A heated gas reaction measuring device.