JPS62245151A - Method for measuring concentration of halogen - Google Patents
Method for measuring concentration of halogenInfo
- Publication number
- JPS62245151A JPS62245151A JP61086190A JP8619086A JPS62245151A JP S62245151 A JPS62245151 A JP S62245151A JP 61086190 A JP61086190 A JP 61086190A JP 8619086 A JP8619086 A JP 8619086A JP S62245151 A JPS62245151 A JP S62245151A
- Authority
- JP
- Japan
- Prior art keywords
- halogen
- anode
- gas
- halogen compound
- concentration
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229910052736 halogen Inorganic materials 0.000 title claims abstract description 22
- 150000002367 halogens Chemical class 0.000 title claims abstract description 22
- 238000000034 method Methods 0.000 title claims description 14
- 150000002366 halogen compounds Chemical class 0.000 claims abstract description 25
- 150000001768 cations Chemical class 0.000 claims abstract description 14
- 239000007789 gas Substances 0.000 claims description 31
- 230000005855 radiation Effects 0.000 claims description 10
- 239000012159 carrier gas Substances 0.000 claims description 8
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 abstract description 28
- 229910052697 platinum Inorganic materials 0.000 abstract description 12
- 229910052783 alkali metal Inorganic materials 0.000 abstract description 11
- 150000001340 alkali metals Chemical class 0.000 abstract description 10
- 150000002500 ions Chemical class 0.000 abstract description 5
- 230000035945 sensitivity Effects 0.000 abstract description 5
- 239000000919 ceramic Substances 0.000 abstract description 3
- 238000010438 heat treatment Methods 0.000 abstract description 3
- 230000000694 effects Effects 0.000 abstract description 2
- 238000004804 winding Methods 0.000 abstract 1
- 238000005259 measurement Methods 0.000 description 14
- 238000010586 diagram Methods 0.000 description 6
- 238000002347 injection Methods 0.000 description 4
- 239000007924 injection Substances 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 2
- GZUXJHMPEANEGY-UHFFFAOYSA-N bromomethane Chemical compound BrC GZUXJHMPEANEGY-UHFFFAOYSA-N 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- -1 sodium is heated Chemical class 0.000 description 2
- WKBOTKDWSSQWDR-UHFFFAOYSA-N Bromine atom Chemical compound [Br] WKBOTKDWSSQWDR-UHFFFAOYSA-N 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 1
- 238000005273 aeration Methods 0.000 description 1
- 239000003570 air Substances 0.000 description 1
- 229910001413 alkali metal ion Inorganic materials 0.000 description 1
- GDTBXPJZTBHREO-UHFFFAOYSA-N bromine Substances BrBr GDTBXPJZTBHREO-UHFFFAOYSA-N 0.000 description 1
- 229910052794 bromium Inorganic materials 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- PXBRQCKWGAHEHS-UHFFFAOYSA-N dichlorodifluoromethane Chemical compound FC(F)(Cl)Cl PXBRQCKWGAHEHS-UHFFFAOYSA-N 0.000 description 1
- 235000019404 dichlorodifluoromethane Nutrition 0.000 description 1
- 239000003673 groundwater Substances 0.000 description 1
- 150000002484 inorganic compounds Chemical class 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 229940102396 methyl bromide Drugs 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 239000008399 tap water Substances 0.000 description 1
- 235000020679 tap water Nutrition 0.000 description 1
Landscapes
- Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は陽イオン放射電流を利用し、環境（大気、水中
）あるいは、排ガス、または環境すなわち大気、もしく
は水中のときはエアレーションを行なって得た試料の中
のハロゲンまたはハロゲン化合物のガス濃度の測定を長
時間にわたって精確に間欠的手段にて行なう方法に関す
る。[Detailed Description of the Invention] [Industrial Application Field] The present invention utilizes positive ion radiation current to emit light into the environment (atmosphere, water) or exhaust gas, or when in the environment (atmosphere or water), by performing aeration. The present invention relates to a method for accurately measuring the gas concentration of a halogen or halogen compound in a sample over a long period of time by intermittent means.
微量のナトリウムなどのアルカリ金属を含む白金陽極を
加熱し、これに陰極を対向させ、その両極間に数１００
Ｖの直流電圧を印加したハロゲンガスセンサに、キャ
リヤガス、たとえば清浄空気を連続通気し、間欠的に電
磁弁などを利用して試料ガスを短時間導入し、次の測定
は所定時間以上の間隔をおいて行なう。このとき試料ガ
ス中のハロゲンまたはハロゲン化合物の濃度が同一であ
るときに、前後する測定時におけるイオン電流出力が実
質的に等しいピーク値を示すように、試料導入時間およ
び試料導入間隔を設定する。A platinum anode containing a trace amount of alkali metal such as sodium is heated, a cathode is placed opposite it, and several hundred nanometers are placed between the two electrodes.
A carrier gas, such as clean air, is continuously passed through the halogen gas sensor to which a DC voltage of V is applied, and a sample gas is intermittently introduced for a short time using a solenoid valve, etc., and the next measurement is performed at intervals of a predetermined time or more. Let's do it. At this time, the sample introduction time and sample introduction interval are set so that when the concentration of the halogen or halogen compound in the sample gas is the same, the ion current outputs in successive measurements show substantially the same peak value.
陽イオン放射電流によるハロゲンまたはハロゲン化合物
の濃度測定は、陽イオンすなわちアルカリ金属イオンを
放射する陽極と、これを受取る陰極との間に、数百ボル
トの直流電圧を印加し、センサ中に導入された試料ガス
中のハロゲンまたはハロゲン化合物の濃度に応じて流れ
る陽イオン電流を検出する。Measuring the concentration of halogens or halogen compounds using cation emission current involves applying a DC voltage of several hundred volts between an anode that emits cations, that is, alkali metal ions, and a cathode that receives them. The positive ion current flowing according to the concentration of halogen or halogen compound in the sample gas is detected.
微量のアルカリ金属を含む白金ホイル、または白金線を
セラミックボビンに巻いた陽極を約７００〜１０００℃
に加熱する。任意にガスまたは大気を接触させる従来の
測定方法では、再現性が悪いので、１１続して精密な濃
度測定を行なうことができず、また比較的安定して測定
できる濃度範囲も０．Ｏ１〜１、０ ｐｐｍと狭く、か
つ、白金陽極の使用寿命も満足なものではなかった。An anode made of platinum foil or platinum wire wrapped around a ceramic bobbin containing a trace amount of alkali metal is heated to approximately 700 to 1000°C.
Heat to. Conventional measurement methods that arbitrarily contact gas or air have poor reproducibility, making it impossible to carry out precise concentration measurements continuously, and the concentration range that can be measured relatively stably is 0. O was as narrow as 1 to 1.0 ppm, and the service life of the platinum anode was also unsatisfactory.
特に比較的高濃度の試料ガスを導入すると、白金陽極表
面のアルカリ金属が大量に消費されるので、陽極表面に
おいてアルカリ金属が不足して、再び試料ガスに曝露し
たときに、感度が著しく低下する（第２図）。このよう
に、連続的測定においては前段階の使用条件によって感
度が変化する。In particular, when a relatively high concentration of sample gas is introduced, a large amount of alkali metal on the surface of the platinum anode is consumed, resulting in a lack of alkali metal on the anode surface and a significant decrease in sensitivity when exposed to the sample gas again. (Figure 2). In this way, in continuous measurement, the sensitivity changes depending on the conditions of use in the previous stage.
そのため従来は陽イオン放射電流出力によるハロゲンま
たはハロゲン化合物の濃度の測定はハロゲンまたはハロ
ゲン化合物の漏洩検出のような半定量的測定に留まって
いた。Therefore, conventionally, the measurement of the concentration of halogen or halogen compound using cation emission current output has been limited to semi-quantitative measurement such as leakage detection of halogen or halogen compound.
本発明の目的は、陽イオン放射電流出力によるハロゲン
またはハロゲン化合物の濃度測定を、感度を低下させず
に、再現性よく、しかも低濃度より高濃度のハロゲンま
たはハロゲン化合物を間欠的に継続して測定することが
でき、しかも白金陽極の使用寿命を伸ばすことである。An object of the present invention is to continuously measure the concentration of a halogen or halogen compound using a cation emission current output with good reproducibility without reducing sensitivity, and to continuously measure the concentration of a halogen or halogen compound at a higher concentration than at a lower concentration. It is possible to measure the platinum anode and extend the service life of the platinum anode.
上記問題点は、陽イオン放射電流による試料ガス中のハ
ロゲンまたはハロゲン化合物の濃度の測定時に、先の試
料ガスを適切な感度が得られる量を間欠的に導入し、測
定する方法を用いる。試料ガス中のハロゲンまたはハロ
ゲン化合物の濃度が同一であるときに、前後する測定時
におけるイオン電流出力が実質的に等しいピーク値を示
すように、試料導入時間を短く、かつ試料導入時間に対
して十分な長さの試料導入間隔を長く設定することを特
徴とする、ハロゲンまたはハロゲン化合物の濃度測定方
法によって解決することができる（第１図）。To solve the above problem, when measuring the concentration of a halogen or a halogen compound in a sample gas using a cation radiation current, a method is used in which the sample gas is intermittently introduced in an amount that provides appropriate sensitivity. The sample introduction time should be short and relative to the sample introduction time so that when the concentration of halogen or halogen compound in the sample gas is the same, the ion current output during successive measurements shows substantially the same peak value. This problem can be solved by a method for measuring the concentration of halogen or halogen compound, which is characterized by setting a sufficiently long sample introduction interval (FIG. 1).
本発明によって、気体中のハロゲン化合物の濃度の測定
において、白金陽極表面に対するハロゲンの曝露量を制
御し、白金陽極内部のアルカリ金属が拡散し表面近傍に
一定量蓄積される時間を確保する。これによって、ハロ
ゲン化合物との接触時間を短くするので、高濃度のガス
が接触しても、白金陽極表面のアルカリ金属の消費量が
少ない。According to the present invention, when measuring the concentration of a halogen compound in a gas, the amount of halogen exposed to the surface of the platinum anode is controlled to ensure time for the alkali metal inside the platinum anode to diffuse and accumulate a certain amount near the surface. This shortens the contact time with the halogen compound, so even if a high concentration gas comes into contact with it, the amount of alkali metal consumed on the surface of the platinum anode is small.
また低濃度のときはアルカリ金属の消費限度において比
較的長時間接触させて測定する。この接触時間をキャリ
ヤガス通気量２０〜５００１１ Ａ ／ｍｉｎにおいて
、０．０５〜４秒、好ましくは０．６〜２秒とし、試料
導入間隔を１秒以上、好ましくは３０秒〜１０分とすれ
ば、後の試料ガス導入時には、前のハロゲン化合物を含
むガスの導入による影響を回避することができ、ハロゲ
ン化合物の濃度が０．０１〜１１０００ｐｐの広範囲で
も測定することができる。In addition, when the concentration is low, the measurement is carried out by keeping the alkali metal in contact for a relatively long time within the consumption limit of the alkali metal. The contact time is set to 0.05 to 4 seconds, preferably 0.6 to 2 seconds at a carrier gas flow rate of 20 to 50011 A/min, and the sample introduction interval is set to 1 second or more, preferably 30 seconds to 10 minutes. For example, when introducing the sample gas later, it is possible to avoid the influence of the previous introduction of a gas containing a halogen compound, and it is possible to measure even in a wide range of halogen compound concentrations from 0.01 to 11000 pp.
また、この方法では、ガスとの連続的接触の場合と比較
し、白金陽極のアルカリ金属の消費が少ないため、セン
サの寿命が長くなる。In addition, this method consumes less alkali metal in the platinum anode compared to continuous contact with gas, resulting in a longer sensor life.
本発明によれば、ガス状ハロゲンであれば、ＰＣＢのよ
うな熱安定性の大きなもの以外は、者機化合物たとえば
塩化ビニルモノマー、臭化メチル等、および無機化合物
たとえば塩素、臭素等も同様に濃度測定を行なうことが
できる。According to the present invention, as long as it is a gaseous halogen, other than those with high thermal stability such as PCB, organic compounds such as vinyl chloride monomer, methyl bromide, etc., and inorganic compounds such as chlorine, bromine, etc. Concentration measurements can be made.
陽イオン放射電流出力測定装置のセンサは、たとえば第
３図（ａｌに示すように、陽極１は白金線コイル２をセ
ラミックボビン３に巻き、陰極４はこれを囲む白金円筒
である。センサの出力回路は第３図（ｂ）に示すように
、陽極１を加熱電源５で加熱する。これによってセラミ
ック中のナトリウムは微量であるが、白金に移行する。The sensor of the cation radiation current output measuring device is, for example, as shown in FIG. As shown in FIG. 3(b), the circuit heats the anode 1 with a heating power source 5. As a result, the sodium in the ceramic is transferred to platinum, although it is a trace amount.
陽極１と陰極４との間に高圧電源６によって１００〜数
百ボルトを印加し、抵抗Ｒによってハロゲン化合物によ
って促進されたアルカリ金属の陽イオン電流による出力
電圧Ｖを測定する。A voltage of 100 to several hundreds of volts is applied between the anode 1 and the cathode 4 by a high-voltage power supply 6, and an output voltage V due to the alkali metal cation current promoted by the halogen compound is measured by a resistor R.
本発明によるハロゲン化合物ガス濃度測定は、たとえば
第４図に示すように、キャリヤガスの遮断、試料ガスの
導入などの動作を行なう電磁弁を介してセンサに試料ガ
スを間欠的に導入する。このときキャリヤガスを通した
まま、試料ガスを間欠的に混入することもできる。電磁
弁は駆動用制御回路によって動作し、またこの回路によ
ってセンサ入出力制御、センサガス出力信号処理を行な
い、ガス濃度として表示する。In the halogen compound gas concentration measurement according to the present invention, for example, as shown in FIG. 4, a sample gas is intermittently introduced into the sensor via a solenoid valve that performs operations such as shutting off the carrier gas and introducing the sample gas. At this time, the sample gas may be mixed intermittently while the carrier gas is being passed through. The solenoid valve is operated by a driving control circuit, and this circuit also controls sensor input/output and processes sensor gas output signals, which are displayed as gas concentration.
キャリヤガスとして清浄空気を１５０ｍ ｌ ／ｍｉｎ
で流し、これに商品名フロン１２ （ＣＧ１２ Ｆ２
）を１２ｐｐｍ含む試料ガス１．５ｍｌを０．６秒間に
注入した。この測定では、抵抗ＲをＩＭΩとして、その
端間電圧を読みとった。150ml/min of clean air as carrier gas
Flush it with water and add the product name Freon 12 (CG12 F2
) was injected in 0.6 seconds. In this measurement, the resistance R was set to IMΩ, and the voltage across it was read.
キャリヤガスのみを６０秒間流した後に、再びさきと同
様に試料ガスを注入する測定を反復し、２０００回の測
定を行なった。その結果各注入時の出力ピーク値は２■
であり、２０００回の測定値が同一出力を示した。After flowing only the carrier gas for 60 seconds, the measurement was repeated by injecting the sample gas in the same manner as before, and 2000 measurements were performed. As a result, the output peak value for each injection was 2■
, and 2000 measurements showed the same output.
センサの構造および出力回路は実施例と同一とし、電磁
弁を使用せず、手動によるコックの切換で試料ガスの注
入時間を５分とし、次の注入までの間隔を５分とした。The structure and output circuit of the sensor were the same as in the example, no solenoid valve was used, and the sample gas injection time was 5 minutes by manual switching of the cock, and the interval until the next injection was 5 minutes.
各注入時の電流出力のピーク値は最初が１６Ｖであり、
次が７Ｖであって、間欠時間が長いにも拘らず、出力の
低下が著しかった・
〔発明の効果〕
本発明は、プラント排ガス、労働環境の空気、ならびに
水道水および地下水をエアレーションした気体中のハロ
ゲンまたはハロゲン化合物の濃度を継続して定量するこ
とができる。The peak value of the current output during each injection is initially 16V,
The next voltage was 7V, and despite the long intermittent time, the output was significantly reduced. [Effects of the Invention] The present invention can be applied to gases obtained by aerating plant exhaust gas, working environment air, tap water, and groundwater. The concentration of halogen or halogen compound can be continuously determined.
第１図は本発明の方法による陽イオン放射電流出力チャ
ート図であり、
第２図は従来の方法による陽イオン放射電流出力チャー
ト図であり、
第３図（ａ）は陽イオン放射電流センサの構造を示す部
分切欠斜視図であり、
第３図（ｂｌは陽イオン放射電流センサの出力回路図で
あり、
第４図は本発明の方法を実施する陽イオン放射電流測定
装置のブロック図である。
１・・・陽極、 ２・・・白金線、 ３・・・ボビ
ン、４・・・陰極、 ５・・・加熱電源、 ６・・・高
圧電源。
（Ｑ）センサの構造
（ｂ）センサ出力回路
第３図Fig. 1 is a cation radiation current output chart diagram according to the method of the present invention, Fig. 2 is a cation radiation current output chart diagram according to the conventional method, and Fig. 3(a) is a cation radiation current output chart diagram of the cation radiation current sensor. FIG. 3 is a partially cutaway perspective view showing the structure; FIG. 3 is an output circuit diagram of a cation radiation current sensor; FIG. 4 is a block diagram of a cation radiation current measuring device that implements the method of the present invention. 1...Anode, 2...Platinum wire, 3...Bobbin, 4...Cathode, 5...Heating power source, 6...High voltage power source. (Q) Sensor structure (b) Sensor Output circuit diagram 3
Claims (1)
を陽イオン放射電流法により間欠的に測定する方法であ
って、試料ガス中のハロゲンまたはハロゲン化合物の濃
度が同一であるときに、前後する測定時におけるイオン
電流出力が実質的に等しいピーク値を示すように、試料
導入時間を短く、かつ試料導入時間に対して試料導入間
隔を長く設定することを特徴とする、ハロゲンまたはハ
ロゲン化合物の濃度測定方法。 ２、試料導入時間を０．０５秒以上とし、試料導入間隔
を１秒以上とする、特許請求の範囲第１項記載の方法。 ３、キャリヤガスを通しながら試料ガスを間欠的に混入
する、特許請求の範囲第１または２項のいずれかに記載
の方法。 ４、キャリヤガスの導入を間欠的に停止し、その間に試
料ガスを導入する、特許請求の範囲第１または２項のい
ずれかに記載の方法。[Claims] 1. A method for intermittently measuring the concentration of a halogen or halogen compound in a sample gas by a cation radiation current method, when the concentration of the halogen or halogen compound in the sample gas is the same. The halogen or Method for measuring the concentration of halogen compounds. 2. The method according to claim 1, wherein the sample introduction time is 0.05 seconds or more, and the sample introduction interval is 1 second or more. 3. The method according to claim 1 or 2, wherein the sample gas is intermittently mixed while passing the carrier gas. 4. The method according to claim 1 or 2, wherein the introduction of the carrier gas is intermittently stopped and the sample gas is introduced during this period.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61086190A JPS62245151A (en) | 1986-04-16 | 1986-04-16 | Method for measuring concentration of halogen |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61086190A JPS62245151A (en) | 1986-04-16 | 1986-04-16 | Method for measuring concentration of halogen |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS62245151A true JPS62245151A (en) | 1987-10-26 |
Family
ID=13879852
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61086190A Pending JPS62245151A (en) | 1986-04-16 | 1986-04-16 | Method for measuring concentration of halogen |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62245151A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6617168B1 (en) * | 1998-01-08 | 2003-09-09 | Omega Co., Ltd. | Evaluation method and evaluation system of free hypohalous acid concentration |
| JP2009139276A (en) * | 2007-12-07 | 2009-06-25 | Taiyo Nippon Sanso Corp | Method and apparatus for measuring fluorine gas |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5531895A (en) * | 1978-08-29 | 1980-03-06 | Bayer Ag | Aqueous polyester dispersed system |
-
1986
- 1986-04-16 JP JP61086190A patent/JPS62245151A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5531895A (en) * | 1978-08-29 | 1980-03-06 | Bayer Ag | Aqueous polyester dispersed system |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6617168B1 (en) * | 1998-01-08 | 2003-09-09 | Omega Co., Ltd. | Evaluation method and evaluation system of free hypohalous acid concentration |
| JP2009139276A (en) * | 2007-12-07 | 2009-06-25 | Taiyo Nippon Sanso Corp | Method and apparatus for measuring fluorine gas |
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