JP6852497B2 - Gas detector and gas detector - Google Patents

Description

The present invention relates to a gas detector and a gas detector capable of easily and sensitively detecting pyrazine compounds.

It is known that pyrazine compounds are produced by the Maillard reaction during cooking of foods, and in particular, lower alkylpyrazines make an important contribution to aroma such as roast. It is also known that methoxypyrazines and the like are contained in certain wines. Therefore, in the production of foods and wines, it is important to accurately evaluate the taste and aroma and control each process based on the results. Conventionally, quality control for taste and odor in the manufacturing process has been performed by an evaluation method such as measuring sugar content, transparency, etc., centering on a sensory test that relies on human senses. However, in recent years, strict quality requirements have been made, and it is difficult to perform sufficient quality control with conventional evaluation methods. Therefore, by evaluating aroma components such as pyrazine compounds, it is possible to evaluate them. Attempts have been made to control the quality of each process.

As a method for detecting pyrazine compounds, there are a method using a semiconductor sensor described in Patent Document 1 and a method using a gas chromatograph mass spectrometry method described in Patent Document 2, but large-scale analytical equipment and gas extraction -There is a problem that it is not possible to measure easily because collection work is required.

Japanese Unexamined Patent Publication No. 6-34592 Japanese Unexamined Patent Publication No. 2016-198092

The present invention has been made in view of the above problems, and an object of the present invention is to provide a gas detector and a gas detector capable of detecting pyrazine compounds more easily and sensitively than before. ..

The present inventors have diligently studied and found that the above object can be achieved by using the metal complex represented by the general formula (1), and have reached the present invention.
M1 _x [Ni _1-y M2 _y (CN) ₄ ] ・ zH ₂ O ・ ・ ・ (1)
(M1 = Fe, Co, 0.9 ≦ x ≦ 1.1, M2 = Pd, Pt, 0 ≦ y <0.15, 2.2 ≦ z <4.4)

That is, according to the present invention, the following are provided.
(1) A gas detection material characterized by using a metal complex represented by the general formula (1).
(2) In the diffraction pattern obtained by powder X-ray diffraction measurement using Cu-Kα as a radiation source, at least 2θ = 19.3 to 21 ° and 30.2 to 31. In the range of 10 ° <2θ <45 °. The gas detection material according to claim 1, wherein a metal complex having a diffraction peak at 2 ° and having a diffraction peak at 2θ = 19.3 to 21 ° showing the strongest integrated intensity is used.
(3) A gas detector using the gas detection material according to (1) or (2).

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a gas detector and a gas detector capable of detecting pyrazine compounds more easily and sensitively than before.

The powder X-ray diffraction pattern figure of the metal complex obtained in Example 1. FIG. The powder X-ray diffraction pattern figure of the metal complex obtained in Example 7. FIG. The powder X-ray diffraction pattern figure of the metal complex obtained in the comparative example 1. FIG. The powder X-ray diffraction pattern figure of the metal complex obtained in the comparative example 2. FIG.

An embodiment (embodiment) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited to the contents described in the following embodiments.

The metal complex of this embodiment is represented by the formula (1).
M1 _x [Ni _1-y M2 _y (CN) ₄ ] ・ zH ₂ O ・ ・ ・ (1)
(M1 = Fe, Co, 0.9 ≦ x ≦ 1.1, M2 = Pd, Pt, 0 ≦ y <0.15, 2.2 ≦ z <4.4)

The metal complex of the present embodiment has a structure in which tetracyanonickate ions and water are regularly arranged in iron ions and / or cobalt ions, so that water and pyrazine compounds can be easily replaced. It is thought that the sensitivity will improve. Further, a part of nickel may be replaced with at least one of palladium and platinum.

As shown in FIG. 1, the metal complex of the present embodiment has a diffraction pattern obtained by powder X-ray diffraction measurement using Cu—Kα as a radiation source, and has at least 2θ = 19.3 in the range of 10 ° <2θ <45 °. It has diffraction peaks at ~ 21 ° and 30.2-31.2 °. When the diffraction peak of 2θ = 19.3 to 21 ° is presumed to be a crystal plane having a large influence on the adsorption of pyrazine compounds, and the diffraction peak of 2θ = 19.3 to 21 ° shows the strongest integrated intensity, It is considered that water can be replaced with pyrazine compounds more easily and the sensitivity will be improved.

The powder X-ray diffraction measurement is performed as follows. The measurement sample is prepared by sprinkling metal complex particles into the recesses of the sample holder and removing excess samples to match the heights of the sample holder surface and the sample measurement surface. The measurement sample was installed in an "Integral IV" X-ray diffractometer manufactured by Rigaku Co., Ltd., and the range of 2θ = 10 ° to 45 ° was measured under the following measurement conditions, and 2θ = 19.3 to 21 ° and 30. The presence or absence of a diffraction peak of 2 to 31.2 ° and the diffraction peak showing the strongest integrated intensity are obtained.
Measurement conditions Filter: Ni
Target: Cu Kα 1.54060 Å
X-ray output setting: 45kV-40mA
Slit: divergence 1/2 °, scattering 1/2 °, light receiving 0.15 mm
Scanning speed: 4 ° / min
Sampling width: 0.02 °

The composition of the metal complex of the present embodiment can be confirmed by using ICP emission spectroscopic analysis, carbon sulfur analysis, oxygen nitrogen hydrogen analysis and the like.

_{Regarding the amount of H 2} O contained in the metal complex of the present embodiment, the mass number of the gas generated when the temperature is raised is confirmed by using a gas chromatograph mass spectrometer equipped with a double shot pyrolyzer, and further. It can be determined by confirming the amount of weight loss using thermogravimetric analysis.

In the method for producing a metal complex of the present embodiment, first, a divalent iron salt or cobalt salt, an antioxidant, and a tetracyanonickate, a tetracyanopallastate, and a tetracyanoplatinate are used as appropriate solvents. A metal complex can be obtained by reacting in a medium, filtering the precipitated precipitate, washing with water, ethanol, or the like, and then drying with an oven or the like.

As the divalent iron salt, ferric sulfate / heptahydrate, ammonium iron sulfate / hexahydrate and the like can be used. As the divalent cobalt salt, cobalt sulfate / heptahydrate, ammonium cobalt sulfate / hexahydrate and the like can be used. As the antioxidant, L-ascorbic acid or the like can be used. As the tetracyanonickate, potassium tetracyanonickate, hydrate or the like can be used. As the tetracyanopalladium salt, potassium tetracyanopalladium acid, hydrate or the like can be used. As the tetracyanoplatinate, potassium tetracyanoplatinate, hydrate or the like can be used.

As the solvent, methanol, ethanol, propanol, water and the like, or a mixed solvent thereof and the like can be used.

The temperature during the reaction in the solvent can be arbitrarily adjusted by heating the reaction vessel using an oil bath or the like.

The metal complex of the present embodiment can be used as a gas detection material for the volatile components of the pyrazine compounds by utilizing the characteristic of adsorbing the volatile components of the pyrazine compounds and changing the color from milky white to orange.

The gas detector of the present embodiment is a molded body in which the gas detection material powder is hardened using a binder or the like, a sheet shape in which the gas detection material powder is supported on a support, and a detection in which the gas detection material powder is sealed in a glass tube. Tubular and the like can be considered, but the present invention is not limited to these.

The gas detector of the present embodiment can be used as a gas detector for the volatile components of the pyrazine compounds by utilizing the feature of adsorbing the volatile components of the pyrazine compounds of the gas detection material and changing the color from milky white to orange. ..

Regarding the gas detection sensitivity, 100 mg of gas detector powder or 100 mg of gas detector and pyrazine compounds were put together in a chalet, covered, and then placed in a constant temperature layer set at 25 ° C., and a milky white metal complex powder. Can be evaluated by confirming the time until the color changes to orange (Munsell value 5YR6.5 / 13 according to the Munsell color system) of the color sample.

By using the gas detector and the gas detector of the present embodiment, the pyrazine compounds can be easily and sensitively detected.

Hereinafter, the present invention will be described based on more detailed examples, but the present invention is not limited to these examples.

<Example 1>
(Manufacturing of metal complex)
Take 0.48 g of ammonium iron (II) sulfate / hexahydrate, 0.2 g of L-ascorbic acid and 0.30 g of potassium tetracyanonick (II) acid / monohydrate in an Erlenmeyer flask, and mix distilled water and ethanol. 480 mL of solvent was added and stirred in an oil bath at 25 ° C. The precipitated particles were collected by filtration and washed with water and ethanol. The particles on the filter paper were collected and dried in an oven at 50 ° C. for 1 hour to obtain a milky white metal complex.

The composition of the obtained metal complex was analyzed by the above-mentioned method. As a result of observation of the gas components when the temperature was raised to 200 ° C. The evolved gas analysis, except that only slightly ethanol was detected is detected H _{2 O,} further weight reduction of up to 200 ° C. by thermal gravimetric analysis than the amount was determined of H _{2 O} content in the metal complex. The composition of the obtained metal complex was Fe [Ni (CN) ₄ ] · 3.1H ₂ O.

When the powder X-ray diffraction pattern (FIG. 1) measured by the above method was confirmed for the obtained metal complex, it had diffraction peaks at 2θ = 19.3 to 21 ° and 30.2 to 31.2 °. The diffraction peak at 2θ = 19.3 to 21 ° showed the strongest integrated intensity.

(Evaluation of gas detection sensitivity)
As a result of evaluating the gas detection sensitivity of pyrazine by the above-mentioned method for the metal complex of Example 1, the color became almost the same as that of the orange color sample after about 7 minutes, and the metal complex of Example 1 made pyrazine highly sensitive. It was found that it can be used as a gas detection material for detection.

(Manufacturing of gas detector)
A roll paper is dipped as a support in a metal complex dispersion in which 50 mg of the metal complex powder of Example 1 is dispersed in 50 ml of pure water, allowed to stand for 2 minutes, removed from the dispersion, and dried in an oven at 50 ° C. for 1 hour. To produce a gas detector.

(Evaluation of gas detection sensitivity)
As a result of evaluating the gas detection sensitivity of pyrazine by the above-mentioned method for the produced gas detector, the color became almost the same as the orange color sample after about 6 minutes and 30 seconds, and it was possible to detect pyrazine with high sensitivity. It turned out that there was.

(Detection of other pyrazine compounds)
When the color change of methylpyrazine, ethylpyrazine, fluoropyrazine and cyanopyridine was confirmed by the above-mentioned method instead of pyrazine, it was confirmed that the color changed to orange. When the color change of cyanopyrazine and bipyridyl was confirmed by the above-mentioned method instead of pyrazine, it was confirmed that the color changed to red. Furthermore, when the color change of triazine was confirmed by the above-mentioned method instead of pyrazine, it was confirmed that the color changed to yellow.
<Example 2>

A metal complex was prepared in the same manner as in Example 1 except that the particles on the collected filter paper were dried in an oven at 45 ° C. for 1 hour. Table 1 shows the results of determining the composition of the metal complex in the same manner as in Example 1. When the powder X-ray diffraction pattern measured in the same manner as in Example 1 was confirmed, it had diffraction peaks at 2θ = 19.3 to 21 ° and 30.2 to 31.2 °, and 2θ = 19.3 to 21. The ° diffraction peak showed the strongest integrated intensity.

(Evaluation of gas detection sensitivity)
When the gas detection sensitivity was evaluated in the same manner as in Example 1 using the metal complex prepared in Example 2, the color became almost the same as the orange color sample after about 7 minutes and 30 seconds, and the metal of Example 2 was obtained. It was found that the complex can be used as a gas detection material for detecting pyrazine with high sensitivity.
<Example 3>

A metal complex was prepared in the same manner as in Example 1 except that the particles on the collected filter paper were dried in an oven at 50 ° C. for 3 hours. Table 1 shows the results of determining the composition of the metal complex in the same manner as in Example 1. When the powder X-ray diffraction pattern measured in the same manner as in Example 1 was confirmed, it had diffraction peaks at 2θ = 19.3 to 21 ° and 30.2 to 31.2 °, and 2θ = 19.3 to 21. The ° diffraction peak showed the strongest integrated intensity.

(Evaluation of gas detection sensitivity)
When the gas detection sensitivity was evaluated in the same manner as in Example 1 using the metal complex prepared in Example 3, the color became almost the same as the orange color sample after about 7 minutes, and the metal complex in Example 3 was found. It was found that it can be used as a gas detection material that detects pyrazine with high sensitivity.
<Example 4>

A metal complex was prepared in the same manner as in Example 1 except that the particles on the collected filter paper were dried in an oven at 55 ° C. for 3 hours. Table 1 shows the results of determining the composition of the metal complex in the same manner as in Example 1. When the powder X-ray diffraction pattern measured in the same manner as in Example 1 was confirmed, it had diffraction peaks at 2θ = 19.3 to 21 ° and 30.2 to 31.2 °, and 2θ = 19.3 to 21. The ° diffraction peak showed the strongest integrated intensity.

(Evaluation of gas detection sensitivity)
When the gas detection sensitivity was evaluated in the same manner as in Example 1 using the metal complex prepared in Example 4, the color became almost the same as the orange color sample after about 7 minutes and 30 seconds, and the metal of Example 4 was obtained. It was found that the complex can be used as a gas detection material for detecting pyrazine with high sensitivity.
<Example 5>

A metal complex was prepared in the same manner as in Example 1 except that 0.45 g of ammonium iron sulfate hexahydrate was added. Table 1 shows the results of determining the composition of the metal complex in the same manner as in Example 1. When the powder X-ray diffraction pattern measured in the same manner as in Example 1 was confirmed, it had diffraction peaks at 2θ = 19.3 to 21 ° and 30.2 to 31.2 °, and 2θ = 19.3 to 21. The ° diffraction peak showed the strongest integrated intensity.

(Evaluation of gas detection sensitivity)
When the gas detection sensitivity was evaluated in the same manner as in Example 1 using the metal complex prepared in Example 5, the color became almost the same as the orange color sample after about 7 minutes and 30 seconds, and the metal of Example 5 was obtained. It was found that the complex can be used as a gas detection material for detecting pyrazine with high sensitivity.
<Example 6>

A metal complex was prepared in the same manner as in Example 1 except that 0.51 g of ammonium iron sulfate hexahydrate was added. Table 1 shows the results of determining the composition of the metal complex in the same manner as in Example 1. When the powder X-ray diffraction pattern measured in the same manner as in Example 1 was confirmed, it had diffraction peaks at 2θ = 19.3 to 21 ° and 30.2 to 31.2 °, and 2θ = 19.3 to 21. The ° diffraction peak showed the strongest integrated intensity.

(Evaluation of gas detection sensitivity)
When the gas detection sensitivity was evaluated in the same manner as in Example 1 using the metal complex prepared in Example 6, the color became almost the same as the orange color sample after about 7 minutes and 30 seconds, and the metal of Example 6 was obtained. It was found that the complex can be used as a gas detection material for detecting pyrazine with high sensitivity.
<Example 7>

A metal complex was prepared in the same manner as in Example 1 except that the particles on the collected filter paper were dried in an oven at 35 ° C. for 1 hour. Table 1 shows the results of determining the composition of the metal complex in the same manner as in Example 1. When the powder X-ray diffraction pattern measured in the same manner as in Example 1 was confirmed (FIG. 2), it had diffraction peaks at 2θ = 19.3 to 21 ° and 30.2 to 31.2 °, and 2θ = 19 The diffraction peak of .3 to 21 ° showed the fifth strongest integrated intensity.

(Evaluation of gas detection sensitivity)
When the gas detection sensitivity was evaluated in the same manner as in Example 1 using the metal complex prepared in Example 7, the color became almost the same as the orange color sample after about 9 minutes and 50 seconds, and the metal of Example 7 was obtained. It was found that the complex can be used as a gas detection material for detecting pyrazine with high sensitivity.
<Comparative example 1>

Except that 160 mL of a mixed solvent of distilled water and ethanol was added to the Erlenmeyer flask, the mixture was stirred in an oil bath at 25 ° C., and the particles on the collected filter paper were dried in an oven at 35 ° C. for 1 hour. A metal complex was prepared in the same manner. When the composition of the metal complex was determined in the same manner as in Example 1, it was Fe [Ni (CN) ₄ ] · 6H ₂ O. When the powder X-ray diffraction pattern measured in the same manner as in Example 1 was confirmed (FIG. 3), no diffraction peak was observed at 2θ = 19.3 to 21 ° and 30.2 to 31.2 °, and the diffraction pattern was observed. It was found from the database of (Fe (H ₂ O) ₂ (Ni (CN) ₄ ) and (H ₂ O) ₄ ).

(Evaluation of gas detection sensitivity)
When the gas detection sensitivity was evaluated in the same manner as in Example 1 using the metal complex prepared in Comparative Example 1, no clear color change could be confirmed after about 10 minutes had passed.
<Comparative example 2>

A metal complex was prepared in the same manner as in Example 1 except that the particles on the collected filter paper were stirred in an oil bath at 75 ° C. and dried in an oven at 35 ° C. for 1 hour. When the composition of the metal complex was determined in the same manner as in Example 1, it was Fe _0.667 [Ni (CN) ₄ ] · 3H ₂ O. When the powder X-ray diffraction pattern measured in the same manner as in Example 1 was confirmed (FIG. 4), no diffraction peak was observed at 2θ = 19.3 to 21 ° and 30.2 to 31.2 °, and the diffraction pattern was observed. It was found that it matches Ni (Fe (CN) ₆ ) _0.667 · (H ₂ O) _{3 from the database of.}

(Evaluation of gas detection sensitivity)
When the gas detection sensitivity was evaluated in the same manner as in Example 1 using the metal complex prepared in Comparative Example 2, no clear color change could be confirmed after about 10 minutes had passed.
<Comparative example 3>

A metal complex was prepared in the same manner as in Example 1 except that the particles on the collected filter paper were dried in an oven at 30 ° C. for 10 minutes. Table 1 shows the results of determining the composition of the metal complex in the same manner as in Example 1.

(Evaluation of gas detection sensitivity)
When the gas detection sensitivity was evaluated in the same manner as in Example 1 using the metal complex prepared in Comparative Example 3, no clear color change could be confirmed after about 10 minutes had passed.
<Comparative example 4>

A metal complex was prepared in the same manner as in Example 1 except that the particles on the collected filter paper were dried in an oven at 80 ° C. for 1 hour. Table 1 shows the results of determining the composition of the metal complex in the same manner as in Example 1.

(Evaluation of gas detection sensitivity)
When the gas detection sensitivity was evaluated in the same manner as in Example 1 using the metal complex prepared in Comparative Example 4, no clear color change could be confirmed after about 10 minutes had passed.

＜実施例８〜１３および比較例５〜７＞

<Examples 8 to 13 and Comparative Examples 5 to 7>

Ammonium iron sulfate hexahydrate, ammonium cobalt sulfate hexahydrate, potassium tetracyanonickel (II) acid monohydrate, potassium tetracyanoplatinate hydrate and tetracyano A metal complex was prepared in the same manner as in Example 1 except that potassium platinate and hydrate were weighed.

(Evaluation of gas detection sensitivity)
When the gas detection sensitivity was evaluated in the same manner as in Example 1 using the metal complexes prepared in Examples 8 to 13 and Comparative Examples 5 to 7, the metal complexes of Examples 8 to 13 were orange within 10 minutes. The color was almost the same as that of the color sample, and it was found that it can be used as a gas detection material to detect pyrazine with high sensitivity. No clear color change could be confirmed after about 10 minutes in the metal complexes prepared in Comparative Examples 5 to 7.

From the above results, it was found that the gas detector produced by using the gas detection material of the example and the metal complex of the example can easily and sensitively detect pyrazine compounds.

Claims (3)

A gas detection material for detecting a pyrazine compound, which comprises using a metal complex represented by the general formula (1).
M1x [Ni1-yM2y (CN) 4] ・ zH2O ・ ・ ・ (1)
(M1 = Fe, Co, 0.9 ≦ x ≦ 1.1, M2 = Pd, Pt, 0 ≦ y <0.15, 2.2 ≦ z <4.4) In the diffraction pattern obtained by powder X-ray diffraction measurement using Cu-Kα as the radiation source, at least 2θ = 19.3 to 21 ° and 30.2 to 31.2 ° in the range of 10 ° <2θ <45 °. The gas detection material according to claim 1, wherein the metal complex having a diffraction peak and having a diffraction peak of 2θ = 19.3 to 21 ° showing the strongest integrated intensity is used. A gas detector using the gas detection material according to claim 1 or 2.

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