JPH01250057A - Method and apparatus for measuring concentration of so2 in gas - Google Patents
Method and apparatus for measuring concentration of so2 in gasInfo
- Publication number
- JPH01250057A JPH01250057A JP7685388A JP7685388A JPH01250057A JP H01250057 A JPH01250057 A JP H01250057A JP 7685388 A JP7685388 A JP 7685388A JP 7685388 A JP7685388 A JP 7685388A JP H01250057 A JPH01250057 A JP H01250057A
- Authority
- JP
- Japan
- Prior art keywords
- hydrogen peroxide
- column
- concentration
- eluate
- absorbing
- 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
- 238000000034 method Methods 0.000 title claims description 21
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims abstract description 78
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims abstract description 36
- 239000003054 catalyst Substances 0.000 claims abstract description 23
- 238000000354 decomposition reaction Methods 0.000 claims abstract description 18
- 229910052697 platinum Inorganic materials 0.000 claims abstract description 17
- 239000007789 gas Substances 0.000 claims abstract description 9
- 238000010521 absorption reaction Methods 0.000 claims description 16
- 239000007788 liquid Substances 0.000 claims description 16
- 238000010438 heat treatment Methods 0.000 claims description 3
- 238000011144 upstream manufacturing Methods 0.000 claims 1
- 229910052760 oxygen Inorganic materials 0.000 abstract description 3
- 239000012141 concentrate Substances 0.000 abstract description 2
- 150000002500 ions Chemical class 0.000 abstract 2
- 239000003957 anion exchange resin Substances 0.000 abstract 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract 1
- 239000001301 oxygen Substances 0.000 abstract 1
- 230000002035 prolonged effect Effects 0.000 abstract 1
- 239000007864 aqueous solution Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000003480 eluent Substances 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 3
- 238000004255 ion exchange chromatography Methods 0.000 description 3
- 238000000926 separation method Methods 0.000 description 3
- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000003456 ion exchange resin Substances 0.000 description 2
- 229920003303 ion-exchange polymer Polymers 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 229910001882 dioxygen Inorganic materials 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000002795 fluorescence method Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000012286 potassium permanganate Substances 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
Landscapes
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、気体、特に大気中のＳ Ｏｚを吸収した過酸
化水素水溶液をイオンクロマトグラフに通してＳＯ□濃
度を測定する方法及び装置に係り、特に、白金触媒を用
いて残留過酸化水素を分解除去した後、ＳＯ２濃度を測
定する方法及び装置に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method and apparatus for measuring the concentration of SO□ by passing a hydrogen peroxide aqueous solution that has absorbed gas, particularly SO in the atmosphere, through an ion chromatograph. In particular, the present invention relates to a method and apparatus for measuring SO2 concentration after decomposing and removing residual hydrogen peroxide using a platinum catalyst.
半導体製品の製造工程では、大気中のＳＯ□が濃度によ
っては製品に影響するため、これを除去する必要があり
、例えば活性炭、過マンガン酸カリウム、アルカリ剤等
を用いたＳＯ２除去材料が使用されている。一方、大気
中のＳＯｚｍ度は、数ｐｌ）ｂ〜数十ｐｐｂであり、こ
の測定方法としては電導度法や紫外線蛍光法等が知られ
ている。しかし、これらの方法では、Ｓ Ｏｚ除去材料
によって処理された後のｐｐｔオーダーのＳＯ２濃度の
測定はできない。In the manufacturing process of semiconductor products, SO□ in the atmosphere affects the product depending on its concentration, so it must be removed. For example, SO2 removal materials such as activated carbon, potassium permanganate, and alkaline agents are used. ing. On the other hand, the degree of SOzm in the atmosphere ranges from several pl)b to several tens of ppb, and methods such as conductivity method and ultraviolet fluorescence method are known as methods for measuring this. However, these methods do not allow measurement of SO2 concentrations on the order of ppt after treatment with SOz removal materials.
このような極微量のＳＯ□濃度の測定方法としては、大
気中の微量のＳＯ２を過酸化水素水溶液に吸収させ、３
０４′−にした後、これをイオンクロマトグラフで分析
する方法が行われている。この方法では、吸収液中で０
．３ ｐｐｂ程度の測定ができ、３時間程度吸収すれば
、ρｐｔオーダーのＳＯ２を測定することができる。As a method for measuring such a trace amount of SO□ concentration, a trace amount of SO2 in the atmosphere is absorbed into an aqueous hydrogen peroxide solution, and
A method has been used in which this is converted to 04'- and then analyzed by ion chromatography. In this method, 0
．． It is possible to measure about 3 ppb, and if it is absorbed for about 3 hours, it is possible to measure SO2 on the order of ρpt.
しかしながら、上記のような過酸化水素水溶液に吸収さ
せる方法では、残留する過酸化水素がイオンクロマトグ
ラフのカラムに充填しであるイオン交換樹脂を劣化させ
、ＳＯ□の正確な測定ができず、また、カラムの寿命を
早めるという欠点があった。However, with the above method of absorbing hydrogen peroxide in an aqueous solution, residual hydrogen peroxide deteriorates the ion exchange resin packed in the ion chromatograph column, making it impossible to accurately measure SO□. , which had the disadvantage of shortening the life of the column.
従って、本発明は、前記の従来技術の欠点を解消し、気
体中のＳＯ□ガスを吸収した過酸化水素水溶液をイオン
クロマトグラフで測定する際に、吸収液中に残留する過
酸化水素を除去することによりＳ Ｏｚを正確に測定し
、また、イオンクロマトグラフのカラムの寿命を延長し
うるＳＯ２の測定方法及び装置を提供することを課題と
する。Therefore, the present invention eliminates the drawbacks of the prior art and removes the hydrogen peroxide remaining in the absorption liquid when measuring an aqueous hydrogen peroxide solution that has absorbed SO□ gas in the gas using an ion chromatograph. An object of the present invention is to provide a method and apparatus for measuring SO2 that can accurately measure SOz and extend the life of an ion chromatograph column.
本発明は、白金触媒を充填したカラムに吸収液を通し、
吸収液中に残留する過酸化水素を白金触媒によって分解
除去した後、イオンクロマトグラフで分析するように構
成することによって上記の課題を解決したものである。The present invention involves passing an absorption liquid through a column packed with a platinum catalyst,
The above problem was solved by configuring the system so that hydrogen peroxide remaining in the absorption liquid is decomposed and removed using a platinum catalyst and then analyzed using an ion chromatograph.
すなわち、本発明によるＳＯ□の測定方法は、気体中の
ＳＯ□を過酸化水素水溶液に吸収させ、ｓｏ、”−にし
た後、この５０４２″″をイオンクロマトグラフを用い
て測定する方法において、吸収液中に残留する過酸化水
素を白金触媒と接触させて分解除去した後、吸収液をイ
オンクロマトグラフに通すことを特徴とする。That is, the method for measuring SO□ according to the present invention involves absorbing SO□ in a gas into an aqueous hydrogen peroxide solution and converting it to so, "-", and then measuring this 5042"" using an ion chromatograph. The method is characterized in that the hydrogen peroxide remaining in the absorption liquid is decomposed and removed by contacting with a platinum catalyst, and then the absorption liquid is passed through an ion chromatograph.
本発明方法を実施する場合、白金触媒を５０℃以上の温
度に加熱しておくと、過酸化水素の分解が効率よく進行
する。When carrying out the method of the present invention, if the platinum catalyst is heated to a temperature of 50° C. or higher, the decomposition of hydrogen peroxide will proceed efficiently.
また、過酸化水素の分解を効率よく行うためには、白金
触媒の表面積を１００ｃ４とし、吸収液をＬｍｌ１分以
下の流量で通水するのが好ましい。Further, in order to efficiently decompose hydrogen peroxide, it is preferable that the surface area of the platinum catalyst be 100c4, and that the absorption liquid be passed at a flow rate of Lml 1 minute or less.
また、本発明によるＳＯ□の測定装置は、白金触媒を充
填した過酸化水素分解カラムをイオンクロマトグラフの
前段に設けたことを特徴とする。Furthermore, the SO□ measuring device according to the present invention is characterized in that a hydrogen peroxide decomposition column filled with a platinum catalyst is provided at the front stage of the ion chromatograph.
上記のように、過酸化水素の分解は、５０℃以上の温度
で効率よく進行するので、白金触媒を加熱する装置を過
酸化水素分解カラムに取り付けるのが好ましい。As mentioned above, decomposition of hydrogen peroxide proceeds efficiently at a temperature of 50° C. or higher, so it is preferable to attach a device for heating the platinum catalyst to the hydrogen peroxide decomposition column.
本発明において、イオンクロマトグラフは、公知のもの
を使用することができる。In the present invention, any known ion chromatograph can be used.
次に、図面に示した実施態様により本発明を説明するが
、本発明はこれに限定されるものではない。Next, the present invention will be explained with reference to embodiments shown in the drawings, but the present invention is not limited thereto.
第１図は、本発明の一実施態様を示す測定装置の系統図
である。図面において、気体中のＳＯ２を吸収した過酸
化水素水溶液、即ち、吸収液は、吸収液槽７に貯蔵され
、ポンプ８によって吸引され、白金触媒を充填した過酸
化水素分解カラム９に通水され、ここで、残留過酸化水
素が分解除去される。過酸化水素分解カラム９には、ヒ
ーター１３が取り付けられており、カラム内の白金触媒
を加熱できるように構成されている。FIG. 1 is a system diagram of a measuring device showing one embodiment of the present invention. In the drawing, an aqueous hydrogen peroxide solution that has absorbed SO2 in the gas, that is, an absorption liquid, is stored in an absorption liquid tank 7, sucked by a pump 8, and passed through a hydrogen peroxide decomposition column 9 filled with a platinum catalyst. , where residual hydrogen peroxide is decomposed and removed. A heater 13 is attached to the hydrogen peroxide decomposition column 9, and is configured to heat the platinum catalyst within the column.
過酸化水素の分解によって発生した酸素ガスをエアート
ラップ１０で除去した後、吸収液を濃縮カラム２に通水
し、吸収液中の３０４′−を濃縮する。次に、切り換え
バルブ１１及び１２を切り換え、溶離液ポンプ１によっ
て溶離液槽６から溶離液を濃縮カラム２に通水し、濃縮
カラム２内の陰イオン交換樹脂に吸着されている３０４
トを溶離し、分離カラム３、除去カラム４を順次通り、
検出器５により３０４′−が検出される。After oxygen gas generated by decomposition of hydrogen peroxide is removed by an air trap 10, the absorption liquid is passed through a concentration column 2 to concentrate 304'- in the absorption liquid. Next, the switching valves 11 and 12 are switched, and the eluent is passed from the eluent tank 6 to the concentration column 2 by the eluent pump 1.
elute and pass sequentially through separation column 3 and removal column 4,
304'- is detected by the detector 5.
なお、図面には、濃縮カラムの前段に過酸化水素分解カ
ラムを設置したが、濃縮カラムを有しないイオンクロマ
トグラフを用いる場合には、分離カラムの前段に設置す
ればよい。In the drawing, a hydrogen peroxide decomposition column is installed before the concentration column, but if an ion chromatograph without a concentration column is used, it may be installed before the separation column.
上記のような装置において、過酸化水素の分解に対する
温度の影響を検討するため、触媒表面積が１００Ｃ！１
１となるように白金粉末を充填した過酸化水素分解カラ
ム９にＨ２０□濃度５０００■／！の過酸化水素水溶液
をｌｄ／分の流量で通水した後、残留ＨＺ Ｏ２′ａ度
を測定した。この実験を触媒温度を４０’Ｃ１５０℃及
び６０°℃で行い、結果を第１表に示す。In order to study the effect of temperature on the decomposition of hydrogen peroxide in the above device, the catalyst surface area was 100C! 1
1 H20□ concentration 5000■/! After passing an aqueous hydrogen peroxide solution at a flow rate of 1 d/min, the residual HZO2'a degree was measured. This experiment was carried out at catalyst temperatures of 40'C, 150°C and 60°C, and the results are shown in Table 1.
第１表
また、過酸化水素の分解に対する触媒表面積の影響を検
討するため、触媒表面積が２０Ｃ１ｉＮ、５０ボ及び１
００ｃｒｌｌとなるように白金粉末を充填し、５０℃に
加熱し−た過酸化水素分解カラムにＨ，Ｏ□濃度５００
０■／ｌの過酸化水素水溶液を１ｍｌ／分の流量で通水
した後、残留Ｈ２０□濃度を測定した。結果を第２表に
示す。Table 1 Also, in order to examine the effect of catalyst surface area on the decomposition of hydrogen peroxide, catalyst surface areas of 20C1iN, 50bo and 1
A H,O
After passing an aqueous hydrogen peroxide solution of 0 □/l at a flow rate of 1 ml/min, the residual H20 □ concentration was measured. The results are shown in Table 2.
第２表
更に、過酸化水素の分解に対する吸収液の流量の影響を
検討するため、触媒表面積が１００ｃ４となるように白
金粉末を充填し、５０℃に加熱した過酸化水素分解カラ
ムにＨ，Ｏ□濃度５０００■／２の過酸化水素水溶液を
０．５ｄ／分、１．０ ｍｌ ７分及び１．５ ｍｌ
７分の流量で通水した後、残留ＨＺ Ｏｚ濃度を測定し
た。結果を第３表に示す。Table 2 Furthermore, in order to examine the effect of the flow rate of the absorption liquid on the decomposition of hydrogen peroxide, a hydrogen peroxide decomposition column packed with platinum powder so that the catalyst surface area was 100c4 and heated to 50°C was charged with H,O □ Hydrogen peroxide aqueous solution with a concentration of 5000/2 at 0.5 d/min, 1.0 ml 7 minutes and 1.5 ml
After water was passed at a flow rate of 7 minutes, the residual HzOz concentration was measured. The results are shown in Table 3.
第３表
このように、本発明方法は、触媒表面積１００ｃＩＩｌ
、温度５０℃以上の白金触媒を充填したカラムに吸収液
を１ｍｌ／分の流量で通水した後、イオンクロマトグラ
フによる分析を行うのが好ましい。Table 3 Thus, the method of the present invention has a catalyst surface area of 100 cIIl.
It is preferable that the absorption liquid is passed through a column filled with a platinum catalyst at a temperature of 50° C. or higher at a flow rate of 1 ml/min, and then analyzed by ion chromatography.
実施例ｌ
３０４２−濃度が５．２０及び５０μｇ／ｌで、ＨｚＯ
ｚ濃度が０．５％の試料を調製し、この試料を第１図に
示した装置で分析した。なお、白金粉末を表面積１００
ｄになるように過酸化水素分解カラムに充填し、これを
５０℃に加熱した後、試料を１ｍ１１分の流速で通水し
、次いで、イオンクロマトグラフでｓｏ４”−濃度を分
析した。分析結果を第４表に示す。Example l 3042 - concentration of 5.20 and 50 μg/l, HzO
A sample with a z concentration of 0.5% was prepared, and this sample was analyzed using the apparatus shown in FIG. In addition, platinum powder has a surface area of 100
After filling the hydrogen peroxide decomposition column with a hydrogen peroxide decomposition column and heating the column to 50°C, water was passed through the sample at a flow rate of 1 ml and 11 min, and the SO4"-concentration was analyzed using an ion chromatograph. Analysis results are shown in Table 4.
比較例
３０４′−濃度が５．２０及び５０μｇ／ｌの試料（Ｈ
２０□を含まない）を調製し、これを直接イオンクロマ
トグラフに通水し、ＳＯａ”ｆＡ度を分析した。分析結
果を第４表に示す。Comparative Example 304' - Samples with concentrations of 5.20 and 50 μg/l (H
20□ was prepared, and this was directly passed through an ion chromatograph to analyze the degree of SOa"fA. The analysis results are shown in Table 4.
第４表
上記の分析結果から明らかなとおり、本発明によれば、
過酸化水素を含まない試料を分析する場合と同等又はそ
れ以上に正確な分析結果が得られる。Table 4 As is clear from the above analysis results, according to the present invention,
Analytical results can be as accurate or more accurate than when analyzing samples that do not contain hydrogen peroxide.
本発明によれば、気体中のＳＯ□を過酸化水素水溶液に
吸収させてイオンクロマトグラフによって５０４′−と
して測定する場合に、水溶液中に残留する過酸化水素を
効率よく分解除去することができ、イオンクロマトグラ
フに過酸化水素を含まない溶液が通水されるので、イオ
ンクロマトグラフに充填されているイオン交換樹脂を劣
化せずに測定を行うことができる。従って、極微債のＳ
Ｏ２でも正確に測定することができ、イオンクロマトグ
ラフの寿命を従来より著しく延長することができる。According to the present invention, when SO□ in a gas is absorbed into an aqueous hydrogen peroxide solution and measured as 504'- by ion chromatography, the hydrogen peroxide remaining in the aqueous solution can be efficiently decomposed and removed. Since a solution that does not contain hydrogen peroxide is passed through the ion chromatograph, measurements can be performed without deteriorating the ion exchange resin filled in the ion chromatograph. Therefore, S of very small debt
Even O2 can be measured accurately, and the life of the ion chromatograph can be significantly extended compared to conventional methods.
第１図は、本発明の一実施態様を示すＳＯ□濃度の測定
装置の系統図である。
２・・・濃縮カラム、３・・・分離カラム、４・・・除
去カラム、５・・・検出器、６・・・溶離液槽、７・・
・吸収液槽、９・・・過酸化水素分解カラム、１３・・
・ヒーターFIG. 1 is a system diagram of an SO□ concentration measuring device showing one embodiment of the present invention. 2... Concentration column, 3... Separation column, 4... Removal column, 5... Detector, 6... Eluent tank, 7...
・Absorption liquid tank, 9...Hydrogen peroxide decomposition column, 13...
·heater
Claims (1)
ＳＯ＿４＾２＾−にした後、このＳＯ＿４＾２＾−をイ
オンクロマトグラフを用いて測定する方法において、吸
収液中に残留する過酸化水素を白金触媒と接触させて分
解除去した後、吸収液をイオンクロマトグラフに通すこ
とを特徴とする気体中のＳＯ＿２濃度の測定方法。 ２、白金触媒を５０℃以上の温度に加熱する請求項１記
載のＳＯ＿２濃度の測定方法。 ３、白金触媒の表面積を１００ｃｍ＾２とし、吸収液を
１ｍｌ／分以下の流量で通水する請求項１又は２記載の
ＳＯ＿２濃度の測定方法。 ４、請求項１記載の方法を実施する装置において、白金
触媒を充填した過酸化水素分解カラムをイオンクロマト
グラフの前段に設けたことを特徴とする気体中のＳＯ＿
２濃度の測定装置。 ５、過酸化水素分解カラムに加熱装置を取り付けた請求
項５記載のＳＯ＿２濃度の測定装置。[Claims] 1. SO_2 in the gas is absorbed into an aqueous hydrogen peroxide solution,
In the method of measuring SO_4^2^- using an ion chromatograph after converting it to SO_4^2^-, hydrogen peroxide remaining in the absorption liquid is decomposed and removed by contacting with a platinum catalyst, and then the absorption liquid is A method for measuring the concentration of SO_2 in a gas, characterized by passing the SO_2 concentration through an ion chromatograph. 2. The method for measuring SO_2 concentration according to claim 1, wherein the platinum catalyst is heated to a temperature of 50°C or higher. 3. The method for measuring SO_2 concentration according to claim 1 or 2, wherein the surface area of the platinum catalyst is 100 cm^2, and the absorption liquid is passed through at a flow rate of 1 ml/min or less. 4. An apparatus for carrying out the method according to claim 1, characterized in that a hydrogen peroxide decomposition column packed with a platinum catalyst is provided upstream of the ion chromatograph.
2 concentration measuring device. 5. The SO_2 concentration measuring device according to claim 5, wherein a heating device is attached to the hydrogen peroxide decomposition column.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7685388A JPH01250057A (en) | 1988-03-30 | 1988-03-30 | Method and apparatus for measuring concentration of so2 in gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7685388A JPH01250057A (en) | 1988-03-30 | 1988-03-30 | Method and apparatus for measuring concentration of so2 in gas |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01250057A true JPH01250057A (en) | 1989-10-05 |
Family
ID=13617210
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7685388A Pending JPH01250057A (en) | 1988-03-30 | 1988-03-30 | Method and apparatus for measuring concentration of so2 in gas |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01250057A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011513707A (en) * | 2008-02-22 | 2011-04-28 | ダイオネックス コーポレイション | Ion chromatography system with flow-delay eluent recycling |
-
1988
- 1988-03-30 JP JP7685388A patent/JPH01250057A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011513707A (en) * | 2008-02-22 | 2011-04-28 | ダイオネックス コーポレイション | Ion chromatography system with flow-delay eluent recycling |
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