JPH0713636B2 - Moisture measuring solvent and water measuring method using the same - Google Patents
Moisture measuring solvent and water measuring method using the sameInfo
- Publication number
- JPH0713636B2 JPH0713636B2 JP61135159A JP13515986A JPH0713636B2 JP H0713636 B2 JPH0713636 B2 JP H0713636B2 JP 61135159 A JP61135159 A JP 61135159A JP 13515986 A JP13515986 A JP 13515986A JP H0713636 B2 JPH0713636 B2 JP H0713636B2
- Authority
- JP
- Japan
- Prior art keywords
- component
- water content
- alkyl group
- solvent
- amount
- 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.)
- Expired - Fee Related
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims description 77
- 239000002904 solvent Substances 0.000 title claims description 35
- 238000000034 method Methods 0.000 title claims description 13
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 45
- 238000005259 measurement Methods 0.000 claims description 26
- XNWFRZJHXBZDAG-UHFFFAOYSA-N 2-METHOXYETHANOL Chemical compound COCCO XNWFRZJHXBZDAG-UHFFFAOYSA-N 0.000 claims description 24
- 125000004178 (C1-C4) alkyl group Chemical group 0.000 claims description 20
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 claims description 20
- 229910052740 iodine Inorganic materials 0.000 claims description 20
- 239000011630 iodine Substances 0.000 claims description 20
- RAXXELZNTBOGNW-UHFFFAOYSA-N imidazole Natural products C1=CNC=N1 RAXXELZNTBOGNW-UHFFFAOYSA-N 0.000 claims description 18
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 claims description 12
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical compound ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 claims description 10
- 125000004435 hydrogen atom Chemical group [H]* 0.000 claims description 10
- 150000007514 bases Chemical class 0.000 claims description 8
- JUJWROOIHBZHMG-UHFFFAOYSA-N Pyridine Chemical compound C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 claims description 6
- 150000002460 imidazoles Chemical class 0.000 claims description 6
- 239000000203 mixture Substances 0.000 claims description 6
- 125000004432 carbon atom Chemical group C* 0.000 claims description 5
- XMBWDFGMSWQBCA-UHFFFAOYSA-N hydrogen iodide Chemical compound I XMBWDFGMSWQBCA-UHFFFAOYSA-N 0.000 claims description 5
- 150000003222 pyridines Chemical class 0.000 claims description 5
- 125000005233 alkylalcohol group Chemical group 0.000 claims description 4
- 229940079865 intestinal antiinfectives imidazole derivative Drugs 0.000 claims description 4
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 claims description 3
- PNDPGZBMCMUPRI-UHFFFAOYSA-N iodine Chemical compound II PNDPGZBMCMUPRI-UHFFFAOYSA-N 0.000 claims description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 14
- 238000004448 titration Methods 0.000 description 7
- 239000010735 electrical insulating oil Substances 0.000 description 6
- 239000003921 oil Substances 0.000 description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- SVEUVITYHIHZQE-UHFFFAOYSA-N n-methylpyridin-2-amine Chemical compound CNC1=CC=CC=N1 SVEUVITYHIHZQE-UHFFFAOYSA-N 0.000 description 4
- 239000004809 Teflon Substances 0.000 description 3
- 229920006362 Teflon® Polymers 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- QBZIEGUIYWGBMY-FUZXWUMZSA-N (5Z)-5-hydroxyimino-6-oxonaphthalene-2-sulfonic acid iron Chemical compound [Fe].O\N=C1/C(=O)C=Cc2cc(ccc12)S(O)(=O)=O.O\N=C1/C(=O)C=Cc2cc(ccc12)S(O)(=O)=O.O\N=C1/C(=O)C=Cc2cc(ccc12)S(O)(=O)=O QBZIEGUIYWGBMY-FUZXWUMZSA-N 0.000 description 2
- RBTBFTRPCNLSDE-UHFFFAOYSA-N 3,7-bis(dimethylamino)phenothiazin-5-ium Chemical compound C1=CC(N(C)C)=CC2=[S+]C3=CC(N(C)C)=CC=C3N=C21 RBTBFTRPCNLSDE-UHFFFAOYSA-N 0.000 description 2
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 2
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical compound CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 description 2
- 229920000459 Nitrile rubber Polymers 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 238000000691 measurement method Methods 0.000 description 2
- 229960000907 methylthioninium chloride Drugs 0.000 description 2
- VBHKTXLEJZIDJF-UHFFFAOYSA-N quinalizarin Chemical compound C1=CC(O)=C2C(=O)C3=C(O)C(O)=CC=C3C(=O)C2=C1O VBHKTXLEJZIDJF-UHFFFAOYSA-N 0.000 description 2
- 229920002379 silicone rubber Polymers 0.000 description 2
- MCTWTZJPVLRJOU-UHFFFAOYSA-N 1-methyl-1H-imidazole Chemical compound CN1C=CN=C1 MCTWTZJPVLRJOU-UHFFFAOYSA-N 0.000 description 1
- LDXJRKWFNNFDSA-UHFFFAOYSA-N 2-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)-1-[4-[2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidin-5-yl]piperazin-1-yl]ethanone Chemical compound C1CN(CC2=NNN=C21)CC(=O)N3CCN(CC3)C4=CN=C(N=C4)NCC5=CC(=CC=C5)OC(F)(F)F LDXJRKWFNNFDSA-UHFFFAOYSA-N 0.000 description 1
- VCUFZILGIRCDQQ-KRWDZBQOSA-N N-[[(5S)-2-oxo-3-(2-oxo-3H-1,3-benzoxazol-6-yl)-1,3-oxazolidin-5-yl]methyl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C1O[C@H](CN1C1=CC2=C(NC(O2)=O)C=C1)CNC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F VCUFZILGIRCDQQ-KRWDZBQOSA-N 0.000 description 1
- SJEYSFABYSGQBG-UHFFFAOYSA-M Patent blue Chemical compound [Na+].C1=CC(N(CC)CC)=CC=C1C(C=1C(=CC(=CC=1)S([O-])(=O)=O)S([O-])(=O)=O)=C1C=CC(=[N+](CC)CC)C=C1 SJEYSFABYSGQBG-UHFFFAOYSA-M 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- GCEHSKLPBDQREK-UHFFFAOYSA-N [I].O=S=O Chemical compound [I].O=S=O GCEHSKLPBDQREK-UHFFFAOYSA-N 0.000 description 1
- 239000000980 acid dye Substances 0.000 description 1
- 239000000981 basic dye Substances 0.000 description 1
- 229920005549 butyl rubber Polymers 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000010494 dissociation reaction Methods 0.000 description 1
- 230000005593 dissociations Effects 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- XMBWDFGMSWQBCA-UHFFFAOYSA-M iodide Chemical compound [I-] XMBWDFGMSWQBCA-UHFFFAOYSA-M 0.000 description 1
- 229940006461 iodide ion Drugs 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000983 mordant dye Substances 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical compound CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 1
- OARRHUQTFTUEOS-UHFFFAOYSA-N safranin Chemical compound [Cl-].C=12C=C(N)C(C)=CC2=NC2=CC(C)=C(N)C=C2[N+]=1C1=CC=CC=C1 OARRHUQTFTUEOS-UHFFFAOYSA-N 0.000 description 1
- 239000000741 silica gel Substances 0.000 description 1
- 229910002027 silica gel Inorganic materials 0.000 description 1
- 239000004945 silicone rubber Substances 0.000 description 1
Landscapes
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明はカールフツシヤー法水分測定において用いられ
る水分測定用溶剤及びこれを用いた水分測定方法に関す
るものである。DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a moisture measuring solvent used in the Karl-Fussier method moisture measurement and a moisture measuring method using the same.
最近のエレクトロニクスの進歩で、水分を簡単に且つ正
確に測定できる水分測定装置が数多く市販されている。
通常の試料の水分測定については、これら水分測定装置
の使用が、便利で有効な方法である。Due to recent advances in electronics, many moisture measuring devices capable of easily and accurately measuring moisture are commercially available.
The use of these water content measuring devices is a convenient and effective method for water content measurement of ordinary samples.
ところが、例えば変圧器に封入されている電気絶縁油の
ように、被水分測定試料を採取した現場で簡単に水分量
を測定したい場合には、このような装置が使えない。し
かしながら電気絶縁油中の水分量を測定することの必要
性は、世間一般に知られているように非常に大きい。電
気絶縁油の劣化は従来は全酸価や絶縁破壊電圧の測定値
でモニタリングされているが、水分含有量との相関が最
もあると言われている。従つて変圧器に封入されている
電気絶縁油のように現場で簡易に水分含有量を測定でき
る試薬、溶剤及び装置等の開発が非常に望まれていた。However, such a device cannot be used when it is desired to easily measure the amount of water at the site where the sample to be measured for moisture is collected, such as the electric insulating oil sealed in the transformer. However, the need for measuring the amount of water in electrically insulating oil is very large as is generally known. Deterioration of electrical insulating oil has been conventionally monitored by measurement values of total acid value and dielectric breakdown voltage, but it is said that it has the highest correlation with water content. Therefore, there has been a great demand for the development of reagents, solvents, devices, etc. that can easily measure the water content on site, such as the electric insulating oil sealed in the transformer.
また電気絶縁油に限らず、各種溶媒を用いた合成反応、
重合反応を行なわせる過程においても、溶媒中の水分量
を簡便に素早く大体の値として知りたいというケースは
数多い。このような場合のために従来から、例えばUSP
3,528,775や特開昭57−103051号などに見られるよう
に、塩基としてピリジンが用いられたカーカフイツシヤ
ー試薬を使用して簡易に水分を測定しようとする試みが
なされてきた。In addition to electrical insulating oil, synthetic reactions using various solvents,
Even in the process of carrying out the polymerization reaction, there are many cases where it is desired to know the water content in the solvent simply and quickly as an approximate value. Conventionally, for example, USP
As seen in 3,528,775 and Japanese Patent Laid-Open No. 57-103051, attempts have been made to easily measure water content by using a Kirka-Fishier reagent in which pyridine is used as a base.
これらの水分測定方法は、水分測定を行なおうとする現
場で水分を含むメタノールに上記カールフイツシヤー試
薬を添加してメタノールを無水化後、試料を添加し、こ
れを上記カールフイツシヤー試薬で滴定するという方法
である。これは、ピリジンの酸解離定数pkaが5.2と低い
ため、溶存するヨウ化物イオンが空気酸化されて簡易水
分測定溶剤としての安定性が得られないためである。These water content measurement methods are carried out by adding the above Karl-Fisher reagent to methanol containing water at the site where water content is to be measured, dehydrating the methanol, adding a sample, and titrating this with the above-mentioned Karl-Fisher reagent. It is a method of doing. This is because the acid dissociation constant pka of pyridine is as low as 5.2, and the dissolved iodide ion is air-oxidized, so that the stability as a simple moisture measuring solvent cannot be obtained.
しかしながら、水分測定を行なう現場でメタノールを無
水化するというこのような操作は、大気中の水分や操作
中に混入する水分の影響及び操作の繁雑さ等のために実
用的なものではなかつた。However, such an operation of dehydrating methanol at the site where the water content is measured is not practical because of the influence of water in the atmosphere and the water mixed during the operation and the complexity of the operation.
本発明者らは従来の簡易水分測定用溶剤がもつ上記した
問題点を解決するために鋭意検討した結果、特定の組成
を有する水分測定用溶剤とすること及びそれを用いて特
定の方法で水分測定を行なうことによつて、水分測定を
より簡便に、素早く行なうことができることを見出して
本発明を完成した。As a result of intensive studies to solve the above-mentioned problems of the conventional simple water content measuring solvent, the present inventors have made a water content measuring solvent having a specific composition and a specific method for using the same. The present invention has been completed by finding that the water content can be measured more simply and quickly by performing the measurement.
即ち、本発明は、 水分を含有する炭素数１〜４のアルキルアルコールであ
る成分（Ａ）と、二酸化硫黄、ヨウ素又はヨウ素化
物、下記一般式（Ｉ）で示されるピリジン誘導体、イ
ミダゾール及び下記一般式（II）で示されるイミダゾー
ル誘導体から選ばれる少なくとも１種の塩基性化合物並
びにメチルセロソルブ、メタノール、クロロホルム又
はこれらの混合物である溶媒から成るカールフィッシャ
ー試薬である成分（Ｂ）とから成り、且つ成分（Ｂ）が
成分（Ａ）を実質的に無水状態にするのに要する量に対
し、ヨウ素換算で0.1〜1.5mM過剰となる量で存在させて
なる水分測定用溶剤、 （上記式中、R1は水素原子又はC1-4のアルキル基を表わ
し、R2はC1-4のアルキル基を表わす） （R3、R4及びR5は夫々水素原子又はC1-4のアルキル基を
表わし、そのうち少なくとも１つはC1-4のアルキル基で
ある） 及びセプタム付密封容器に収容された該水分測定用溶剤
に、該セプタムを通して所定量の被水分測定試料を添加
して十分混合した後、一定量のカールフィッシャー試薬
を添加して十分混合する滴定操作を滴定終点に到達する
迄繰返し、該カールフィッシャー試薬の添加合計量に対
応する水分量を上限として該被水分測定試料中の水分量
を測定することを特徴とする水分測定方法、 を要旨とするものである。That is, the present invention includes a component (A) which is a water-containing alkyl alcohol having 1 to 4 carbon atoms, sulfur dioxide, iodine or an iodide, a pyridine derivative represented by the following general formula (I), imidazole and the following general formula: A component (B) which is a Karl Fischer reagent comprising at least one basic compound selected from the imidazole derivatives represented by the formula (II) and a solvent which is methyl cellosolve, methanol, chloroform or a mixture thereof, and A solvent for measuring water, which is present in an amount of 0.1 to 1.5 mM excess in terms of iodine in excess of the amount of (B) required to render the component (A) substantially anhydrous, (In the above formula, R 1 represents a hydrogen atom or a C 1-4 alkyl group, and R 2 represents a C 1-4 alkyl group) (R 3 , R 4 and R 5 each represent a hydrogen atom or a C 1-4 alkyl group, at least one of which is a C 1-4 alkyl group) and the moisture contained in a sealed container with a septum. A predetermined amount of the sample to be measured is added to the solvent for measurement through the septum and thoroughly mixed, and then a fixed amount of the Karl Fischer reagent is added and sufficiently mixed. The titration operation is repeated until the titration end point is reached. A method for measuring water content is characterized in that the water content in the sample to be measured is measured with the upper limit of the water content corresponding to the total amount of Fischer reagent added.
以下に、本発明につき更に詳細に説明する。The present invention will be described in more detail below.
本発明の水分測定溶剤は、水分を含有する炭素数１〜４
のアルキルアルコールである成分（Ａ）と、二酸化硫
黄、ヨウ素又はヨウ素化物、下記一般式（Ｉ）で示
されるピリジン誘導体、イミダゾール及び下記一般式
（II）で示されるイミダゾール誘導体から選ばれる少な
くとも１種の塩基性化合物並びにメチルセロソルブ、
メタノール、クロロホルム又はこれらの混合物である溶
媒から成るカールフィッシャー試薬である成分（Ｂ）と
から成り、且つ成分（Ｂ）が成分（Ａ）を実質的に無水
状態にするのに要する量に対し、ヨウ素換算で0.1〜1.5
mM過剰となる量で存在させてなるものである。The solvent for measuring water content of the present invention has 1 to 4 carbon atoms containing water.
At least one selected from the component (A), which is an alkyl alcohol, and sulfur dioxide, iodine or an iodide, a pyridine derivative represented by the following general formula (I), imidazole and an imidazole derivative represented by the following general formula (II). Basic compounds and methyl cellosolve,
And a component (B) which is a Karl Fischer reagent consisting of a solvent which is methanol, chloroform or a mixture thereof, and the amount of component (B) required to make component (A) substantially anhydrous, 0.1-1.5 in iodine equivalent
It is made to exist in an amount that makes mM excess.
（上記式中、R1は水素原子又はC1-4のアルキル基を表わ
し、R2はC1-4のアルキル基を表わす） （R3、R4及びR5は夫々水素原子又はC1-4のアルキル基を
表わし、そのうち少なくとも１つはC1-4のアルキル基で
ある） 上記成分（Ａ）としては、メタノール、エタノール、ｎ
−プロパノール、イソプロパノール、ブタノールなどの
炭素数１〜４のアルキルアルコールが用いられるが、そ
の中でもメタノールが最適である。 (In the above formula, R 1 represents a hydrogen atom or a C 1-4 alkyl group, and R 2 represents a C 1-4 alkyl group) (R 3 , R 4 and R 5 each represent a hydrogen atom or a C 1-4 alkyl group, at least one of which is a C 1-4 alkyl group) As the component (A), methanol, ethanol , N
-Alkanols having 1 to 4 carbon atoms such as propanol, isopropanol and butanol are used, and among them, methanol is most suitable.
また、成分（Ａ）中の水分含有量は、特に制限されない
が、含有量が多いと無水化に多量のカールフイツシヤー
試薬を要するため少ない方が好ましく、通常、0.1％以
下、好ましくは、0.01〜0.03％のものが選ばれる。Further, the water content in the component (A) is not particularly limited, but it is preferable that the water content is small because a large amount of the Karl Fischer reagent is required for dehydration, and it is usually 0.1% or less, preferably 0.01% or less. ~ 0.03% is selected.
上記成分（Ｂ）としては 二酸化硫黄 ヨウ素又はヨウ素化物 下記一般式（Ｉ） （上記式中、R1は水素原子又はC1-4のアルキル基を表わ
し、R2はC1-4のアルキル基を表わす） で示されるピリジン誘導体、イミダゾール及び下記一般
式（II） （R3、R4及びR5は夫々水素原子又はC1-4のアルキル基を
表わし、そのうち少なくとも１つはC1-4のアルキル基で
ある）で示されるイミダゾール誘導体から選ばれる少な
くとも一種の塩基性化合物、 並びに、 メチルセロソルブ、メタノール、クロロホルム又は
これらの混合物である溶媒 から成るカールフィッシャー試薬を用いる。As the above-mentioned component (B), sulfur dioxide iodine or iodide (In the above formula, R 1 represents a hydrogen atom or a C 1-4 alkyl group, and R 2 represents a C 1-4 alkyl group), a pyridine derivative represented by the formula: imidazole and the following general formula (II) (R 3 , R 4 and R 5 each represent a hydrogen atom or a C 1-4 alkyl group, at least one of which is a C 1-4 alkyl group) and at least one selected from imidazole derivatives A Karl Fischer reagent consisting of a basic compound and a solvent which is methyl cellosolve, methanol, chloroform or a mixture thereof is used.
尚、の塩基性化合物のピリジン誘導体としては、２−
メチルアミノピリジンが好ましく、またイミダゾール誘
導体としては、１−メチルイミダゾールが好適である。In addition, as the pyridine derivative of the basic compound,
Methylaminopyridine is preferable, and 1-methylimidazole is preferable as the imidazole derivative.
上記成分（Ｂ）中の〜の各成分の使用濃度は二酸化
硫黄が通常0.3〜2M、ヨウ素（I2）が通常、0.05〜0.5
M、また、塩基性化合物が通常、0.3〜2M、好ましくは0.
5〜1.5Mの範囲となるように選ばれる。In the above component (B), the concentration of each of the components (1) to ( 3 ) is usually 0.3 to 2M for sulfur dioxide and 0.05 to 0.5 for iodine (I 2 ).
M, and the basic compound is usually 0.3 to 2M, preferably 0.
Selected to be in the range of 5 to 1.5M.
本発明の水分測定用溶剤は、上記成分（Ａ）及び上記成
分（Ｂ）を特定の割合で存在させてなるものである。The water content measuring solvent of the present invention comprises the above component (A) and the above component (B) in a specific ratio.
即ち、上記成分（Ｂ）が成分（Ａ）の水分を含有するア
ルコールを実質的に無水状態にするのに必要な量に対し
てヨウ素換算で0.1〜1.5mM、好ましくは、0.4〜0.8mM
（H2O換算で7.2〜14.4μg/mlに相当する）過剰な量で存
在させてなるものである。That is, the above component (B) is 0.1 to 1.5 mM, preferably 0.4 to 0.8 mM, in terms of iodine, with respect to the amount required to make the water-containing alcohol of the component (A) substantially anhydrous.
It is made to exist in an excessive amount (corresponding to 7.2 to 14.4 μg / ml in terms of H 2 O).
水分測定用溶剤を収容するセプタム付密封容器（後述す
る）には、若干の水分が含まれており、また空気中の湿
気等の影響もあることから、これらの水分量（通常1.5m
M程度まで）に見合う量で成分（Ｂ）を添加しておくこ
とが正確な水分測定を行なう上では望ましい。The sealed container with a septum (described later) that contains the solvent for water content contains a small amount of water and is affected by humidity in the air.
It is desirable to add the component (B) in an amount commensurate with (up to about M) in order to accurately measure water content.
しかしながら、このような厳密な添加量の制御を都度行
なうことは水分測定操作を繁雑なものとし、簡便かつ素
早い水分測定を行なうことができない。However, performing such strict control of the amount of addition every time complicates the moisture measurement operation, and cannot perform simple and quick moisture measurement.
また、あまり過度に成分（Ｂ）を加えておくことは、被
水分測定結果を不正確なものとすることになる。従つ
て、水分測定用溶剤を収容する密封容器及び空気中の湿
気等に由来する通常1.5mM程度までの水分量を許容すべ
く成分（Ａ）及び成分（Ｂ）を上記の割合で存在させ
る。In addition, adding the component (B) excessively excessively makes the measurement result of water content inaccurate. Therefore, the component (A) and the component (B) are present in the above proportions so as to allow a water content of up to about 1.5 mM due to moisture in the air and a sealed container containing the solvent for measuring water content.
本発明の水分測定用溶剤は、例えば次の様にして調製さ
れる。The solvent for measuring water content of the present invention is prepared, for example, as follows.
即ち、上記成分（Ａ）をセプタム付き密封容器に、例え
ばその容積の約1/3程度入れる。成分（Ａ）は前述程度
の量の水分を含んでいるので成分（Ｂ）を添加して水分
の無水化を行なう。この時の反応は成分（Ｂ）としてメ
タノールを例にして示すと下式（III）の通りである。That is, the above component (A) is placed in a sealed container with a septum, for example, about 1/3 of its volume. Since the component (A) contains the above-mentioned amount of water, the component (B) is added to dehydrate the water. The reaction at this time is represented by the following formula (III) when methanol is used as an example of the component (B).
CH3OH＋H2O＋SO2＋I2＋3Base→2Base・HI＋Base ・HSO4CH3 ……（III） ここでBaseは塩基性化合物を表わしている。CH 3 OH ＋ H 2 O ＋ SO 2 ＋ I 2 ＋ 3Base → 2Base ・ HI + Base ・ HSO 4 CH 3 …… (III) Here, Base represents a basic compound.
低級アルコール中の水が完全になくなるまで成分（Ｂ）
を水と反応させたあと、ヨウ素（I2）換算で0.1〜1.5m
M、好ましくは0.4〜0.8mM過剰（この過剰量はH2O換算で
7.2〜14.4μg/mlに相当する）になるように更に成分
（Ｂ）を加える。Component (B) until the water in the lower alcohol is completely consumed
After reacting with water, 0.1-1.5m in terms of iodine (I 2 )
M, preferably 0.4 to 0.8 mM excess (this excess is calculated as H 2 O
Further, the component (B) is added so that the amount becomes 7.2 to 14.4 μg / ml).
前記密封容器としては本願発明の水分測定用溶剤を大気
中の水分が入らないように密封して収容し、かつ、滴定
操作に際して終点の確認できるものであつて、試料及び
カールフイツシヤー試薬の添加のためのセプタムを備え
たものが用いられる。その材質は、できるだけ水分含有
量の少ないものが好ましい。As the sealed container, the solvent for moisture measurement of the present invention is sealed and stored so that moisture in the atmosphere does not enter, and the end point can be confirmed during the titration operation, and the sample and the Karl Fisher reagent are added. The one with a septum for is used. The material is preferably as low as possible in water content.
セプタムは試料及びカールフイツシヤー試薬の添加を行
なうために注射針が差し込めるものであればよく、また
当然のこととして水分含有量の少ない材質のブチルゴ
ム、NBR（アクリロニトリル・ブタジエンゴム）、シリ
コンゴムなどが適しており、更にテフロン膜又はテフロ
ンコーテイングの処理が施してあれば更に好適である。The septum only needs to be one into which an injection needle can be inserted in order to add the sample and the Karl Fischer reagent, and of course, butyl rubber, NBR (acrylonitrile-butadiene rubber), silicone rubber, etc., which have a low water content. Is more preferable, and it is more preferable if it is further treated with a Teflon film or a Teflon coating.
このようにして調製した水分測定用溶剤は安定で、シリ
カゲルを入れたデシケーター中（湿度10％程度）では３
ケ月以上も安定（水分の吸収をせずほぼ無水の状態が保
たれる）でまた実験室での保管下（湿度40〜80％）でも
１ケ月は安定に保持することができる。The solvent for moisture measurement prepared in this way is stable, and is 3% in a desiccator containing silica gel (humidity of about 10%).
It is stable for more than a month (maintains an almost anhydrous state without absorbing water) and can be kept stable for a month even under storage in a laboratory (humidity 40 to 80%).
また、本発明においては、このように安定性の良好な水
分測定溶剤を用いた特定の水分測定方法で水分測定を行
なうことによつて簡便、かつ、素早く水分測定を行なう
ことを可能にした。Further, in the present invention, the water content can be measured simply and quickly by performing the water content measurement by the specific water content measurement method using the water content measurement solvent having good stability.
即ち、セプタム付密封容器に収容された上記した水分測
定溶剤に該セプタムを通して所定量の被水分測定試料を
添加して十分混合した後、一定量のカールフイツシヤー
試薬を添加して十分混合する滴定操作を滴定終点に到達
する迄繰返し、該カールフイツシヤー試薬の添加合計量
に対応する水分量を上限として、該被水分測定試料中の
水分量を測定することができる。また、該カールフイツ
シヤー試薬の添加合計量に対応する水分量を上限とし、
滴定終点に到達する１回前までの該カールフイツシヤー
試薬の添加量の合計に対応する水分量を下限とする範囲
に属する値として該被水分測定試料中の水分量を測定す
ることができる。That is, titration in which a predetermined amount of the sample to be measured is added to the solvent for moisture measurement stored in a sealed container with a septum through the septum and sufficiently mixed, and then a predetermined amount of the Karl Fischer reagent is added and sufficiently mixed. The operation can be repeated until the titration end point is reached, and the water content in the sample to be measured can be measured with the water content corresponding to the total amount of the Karl Fischer reagent added as the upper limit. Further, the upper limit is the water content corresponding to the total amount of the Karl Fischer reagent added,
The amount of water in the sample to be measured can be measured as a value in the range of which the lower limit is the amount of water corresponding to the total amount of the Karl Fischer reagent added until the end of the titration.
上記水分測定用溶剤を使用して電気絶縁油等の試料の水
分を簡易に測定することができる。It is possible to easily measure the water content of a sample such as electric insulating oil using the water content measurement solvent.
例えば、本発明の水分測定用溶剤10mlを収容したセプタ
ム付き密封容器中に試料を10ml注入し、よく振とう後、
静置して力価既知のカールフイツシヤー試薬の一定量を
添加する。例えば、力価3mgH2O/mlのカールフイツシヤ
ー試薬を0.1ml添加し、振とう後静置してメタノール層
がヨウ素（I2）の色になれば試料中の水分は約30μg/ml
以下であることが判る。そのときヨウ素（I2）の色が末
だ現われていなければ更に0.1ml添加して同様にヨウ素I
2の色が現われるまで繰り返す。For example, 10 ml of a sample was injected into a sealed container with a septum containing 10 ml of the solvent for measuring water content of the present invention, and after shaking well
Allow to stand and add a fixed amount of Karl Fischer reagent of known titer. For example, add 0.1 ml of Karl-Fisher's reagent with a titer of 3 mg H 2 O / ml, shake and let stand, and if the methanol layer becomes the color of iodine (I 2 ), the water content in the sample will be about 30 μg / ml.
It turns out that: At that time, if the color of iodine (I 2 ) does not appear, add 0.1 ml of iodine and similarly add iodine I.
Repeat until the second color appears.
上記の様にカールフイツシヤー試薬を一定量、即ち0.1m
lずつ加えてゆき、ヨウ素（I2）の色の出現を確認して
いけば30μgH2O/mlの間隔で水分の簡易測定が可能であ
ることになる。試料量、カールフイツシヤー試薬の力価
及びカールフイツシヤー試薬の添加量を適当に変えるこ
とによつて測定できる水分含有量の範囲は変えられる。As described above, use a fixed amount of Karl Fischer reagent, namely 0.1m.
By adding l at a time and confirming the appearance of the color of iodine (I 2 ), it is possible to perform a simple measurement of water at intervals of 30 μg H 2 O / ml. The range of measurable water content can be changed by appropriately changing the sample amount, the titer of the Karl Fischer reagent and the addition amount of the Karl Fischer reagent.
このように、本発明の水分測定方法によれば水分測定に
当たちて操作の繁雑なカールフイツシヤー滴定装置を用
いることなく何ら場所を選ばず、簡便に、素早く、大体
の値を知ることができる。As described above, according to the water content measuring method of the present invention, it is possible to know the approximate value easily, quickly and without selecting any place without using a complicated Karl Fisher titrator for the water content measurement. it can.
試料は必ずしも無色又は淡黄色のものばかりではなく、
時にはかなり古い電気絶縁油の様に褐色のものがある。
このような場合には指示薬を用いて反応の終点を判別す
るのがよい。指示薬としては以下のものが使用できる。The samples are not always colorless or pale yellow,
Sometimes there is a brown one, like fairly old electrical insulating oil.
In such a case, it is better to use an indicator to determine the end point of the reaction. The following can be used as indicators.
ｉ） 塩基性染料系、例えばメチレンブルー、サフラニ
ン等 ii） 酸性染料系、例えば、ナフトールグリーンＢ等 iii） 媒染染料系、例えば、キナリザリン等 上記指示薬は単独で、又は混合して用いることができ
る。i) Basic dyes such as methylene blue, safranine and the like ii) Acid dyes such as naphthol green B and the like iii) Mordant dyes such as quinalizarin and the like, and the above indicators can be used alone or in combination.
上記した中でも特にメチレンブルー、ナフトールグリー
ンＢ及びキナリザリンの混合系が最適である。指示薬を
添加する場合の添加量は通常0.1〜50ppm、好ましくは0.
5〜15ppmの範囲である。Among the above, a mixed system of methylene blue, naphthol green B and quinalizarin is most suitable. When the indicator is added, the amount added is usually 0.1 to 50 ppm, preferably 0.
It is in the range of 5 to 15 ppm.
以下に実施例により本発明を更に具体的に説明するが、
本発明はその要旨を超えない限り以下の実施例によつて
限定されるものではない。Hereinafter, the present invention will be described more specifically with reference to Examples.
The present invention is not limited to the following examples unless it exceeds the gist.
実施例−１ メタノール（水分含有量約100ppm）10mlをセプタム付き
密封容器（容積約30ml）に入れた。このメタノール中の
水分を無水化するため、二酸化硫黄0.8M、ヨウ素0.3M、
２−メチルアミノピリジン1.2M及び溶媒がメチルセロソ
ルブから成る力価約3mgH2O/mlのカールフイツシヤー試
薬（以下、「KF試薬」という）を注射器にてセプタムを
通して0.33ml添加したところヨウ素の色が出現し、無水
化したことを確認した。そのあと更に該KF試薬を0.025m
l添加して水分測定用溶剤とした。Example-1 10 ml of methanol (water content: about 100 ppm) was placed in a sealed container with a septum (volume: about 30 ml). To dehydrate the water in this methanol, sulfur dioxide 0.8M, iodine 0.3M,
When 0.33 ml of Karl-Fisher's reagent (hereinafter referred to as "KF reagent") with a titer of about 3 mg H 2 O / ml consisting of 1.2 M of 2-methylaminopyridine and methyl cellosolve as a solvent was added through a septum with a syringe, the color of iodine Appeared and was confirmed to be dehydrated. After that, further add 0.025 m of the KF reagent.
l was added to make a solvent for moisture measurement.
この時のヨウ素（I2）濃度は0.75mMであつた。セプタム
にはシリコンゴム（水分量0.027％）の表面にテフロン
膜をはりつけたものを使用した。The iodine (I 2 ) concentration at this time was 0.75 mM. The septum used was a silicon rubber (water content 0.027%) with a Teflon film attached to the surface.
上記水分測定用溶剤に変圧器より採取した電気絶縁油10
mlを注射器でセプタムを通して添加した。約30秒間激し
く振とうし、静置した。Electrical insulating oil sampled from a transformer in the water content measurement solvent 10
ml was added via syringe through the septum. Shake vigorously for about 30 seconds and let stand.
上記KF試薬0.1mlを注射器で添加したあと、再び約30秒
間振とうし、静置した。メタノール層におけるヨウ素
（I2）の色の有無で電気絶縁油中の水分の有無を判定し
た。ヨウ素（I2）の色が未だ表われなかつたので更に0.
1mlのKF試薬を添加して同様のことを行つた。今度はヨ
ウ素（I2）の色が表われた。従つてこの電気絶縁油中の
水分は30μg/ml〜60μg/mlの範囲であることがわかつ
た。After adding 0.1 ml of the above KF reagent with a syringe, it was shaken again for about 30 seconds and allowed to stand. The presence or absence of water in the electrical insulating oil was determined by the presence or absence of the color of iodine (I 2 ) in the methanol layer. The color of iodine (I 2 ) has not yet appeared, so 0.
The same was done by adding 1 ml of KF reagent. This time, the color of iodine (I 2 ) appeared. Therefore, it was found that the water content in this electrical insulating oil was in the range of 30 μg / ml to 60 μg / ml.
尚、市販の水分測定装置を用いて精密な水分量の測定を
行なつたところ、39μg/mlであつた。The water content was 39 μg / ml when measured accurately using a commercially available water content measuring device.
実施例−２ KF試薬における２−メチルアミノピリジンの代わりにイ
ミダゾールを用いたこと以外は実施例−１と同様にして
行なつたところ、実施例−１と同様の測定結果が得られ
た。Example-2 The same measurement result as in Example-1 was obtained by the same procedure as in Example-1 except that imidazole was used instead of 2-methylaminopyridine in the KF reagent.
実施例−３ KF試薬における２−メチルアミノピリジンの代わりに２
−メチルイミダゾールを用いたこと以外は実施例−１と
同様にして行なつたところ、実施例−１と同様の測定結
果が得られた。Example-3 2 instead of 2-methylaminopyridine in KF reagent
When the same procedure as in Example-1 was carried out except that -methylimidazole was used, the same measurement result as in Example-1 was obtained.
本発明の水分測定の溶剤は、長期間にわたつて水分を吸
収することなく、ほぼ無水の状態を安定に維持し得るの
で本発明の水分測定溶剤によれば従来水分測定に当たつ
て行なつていた被水分測定試料の溶剤を無水化するため
の繁雑な操作を必要とせず、簡便に、素早く水分測定を
行なうことができる。本発明の水分測定溶剤を用いた水
分測定方法によれば水分測定に当たつて操作の繁雑なカ
ールフイツシヤー滴定装置を用いることなく、何ら場所
を選ばずに簡便に素早く、かつ大体の値を知ることがで
きる。特に変圧器に封入されている電気絶縁油等の水分
を簡易に測定するのに好適である。The solvent for moisture measurement of the present invention does not absorb moisture over a long period of time, and can maintain a substantially anhydrous state stably. Therefore, the solvent for moisture measurement of the present invention can be used for conventional moisture measurement. The complicated measurement for dehydrating the solvent of the sample to be measured, which is required, is not required, and the moisture can be measured easily and quickly. According to the water content measuring method using the water content measuring solvent of the present invention, without using a complicated Karl-Fisher titration device for the water content measurement, the location can be selected easily and quickly, and the approximate value can be obtained. I can know. Particularly, it is suitable for easily measuring the water content of the electric insulating oil and the like enclosed in the transformer.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 角田 章 愛知県名古屋市緑区鳴海町京田３−31 財 団法人中部電気保安協会電気試験所内 (56)参考文献 特開 昭55−15019（ＪＰ，Ａ) 特公 昭33−1750（ＪＰ，Ｂ１) 特公 昭52−34957（ＪＰ，Ｂ２) ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Kakuda 3-31 Kyoda, Narumi-cho, Midori-ku, Nagoya-shi, Aichi Pref. Chubu Electric Safety Association Electric Test Laboratory (56) Reference JP-A-55-15019 (JP, A) JP-B 33-1750 (JP, B1) JP-B 52-34957 (JP, B2)
Claims (2)
ルコールである成分（Ａ）と、二酸化硫黄、ヨウ素
又はヨウ素化物、下記一般式（Ｉ）で示されるピリジ
ン誘導体、イミダゾール及び下記一般式（II）で示され
るイミダゾール誘導体から選ばれる少なくとも１種の塩
基性化合物並びにメチルセロソルブ、メタノール、ク
ロロホルム又はこれらの混合物である溶媒から成るカー
ルフィッシャー試薬である成分（Ｂ）とから成り、且つ
成分（Ｂ）が成分（Ａ）を実質的に無水状態にするのに
要する量に対し、ヨウ素換算で0.1〜1.5mM過剰となる量
で存在させてなる水分測定用溶剤。 （上記式中、R1は水素原子又はC1-4のアルキル基を表わ
し、R2はC1-4のアルキル基を表わす） （R3、R4及びR5は夫々水素原子又はC1-4のアルキル基を
表わし、そのうち少なくとも１つはC1-4のアルキル基で
ある）1. A component (A) which is a water-containing alkyl alcohol having 1 to 4 carbon atoms, sulfur dioxide, iodine or an iodide, a pyridine derivative represented by the following general formula (I), imidazole and the following general formula. (II) at least one basic compound selected from imidazole derivatives and a component (B) which is a Karl Fischer reagent consisting of a solvent which is methyl cellosolve, methanol, chloroform or a mixture thereof, and a component ( A solvent for measuring moisture, which is present in an amount of 0.1 to 1.5 mM excess in terms of iodine in excess of the amount of B) required to bring the component (A) into a substantially anhydrous state. (In the above formula, R 1 represents a hydrogen atom or a C 1-4 alkyl group, and R 2 represents a C 1-4 alkyl group) (R 3 , R 4 and R 5 each represent a hydrogen atom or a C 1-4 alkyl group, at least one of which is a C 1-4 alkyl group)
有する炭素数１〜４のアルキルアルコールである成分
（Ａ）と二酸化硫黄、ヨウ素又はヨウ素化物、下
記一般式（Ｉ）で示されるピリジン誘導体、イミダゾー
ル及び下記一般式（II）で示されるイミダゾール誘導体
から選ばれる少なくとも１種の塩基性化合物並びにメ
チルセロソルブ、メタノール、クロロホルム又はこれら
の混合物である溶媒から成るカールフィッシャー試薬で
ある成分（Ｂ）とから成り、且つ成分（Ｂ）が成分
（Ａ）を実質的に無水状態にするのに要する量に対し、
ヨウ素換算で0.1〜1.5mM過剰となる量で存在させてなる
水分測定用溶剤に、該セプタムを通して所定量の被水分
測定試料を添加して十分混合した後、一定量のカールフ
ィッシャー試薬を添加して十分混合する滴定操作を滴定
終点に到達する迄繰返し、該カールフィッシャー試薬の
添加合計量に対応する水分量を上限として該被水分測定
試料中の水分量を測定することを特徴とする水分測定方
法。 （上記式中、R1は水素原子又はC1-4のアルキル基を表わ
し、R2はC1-4のアルキル基を表わす） （R3、R4及びR5は夫々水素原子又はC1-4のアルキル基を
表わし、そのうち少なくとも１つはC1-4のアルキル基で
ある）2. A component (A) which is a water-containing alkyl alcohol having 1 to 4 carbon atoms and is contained in a sealed container with a septum, sulfur dioxide, iodine or an iodide, and a pyridine represented by the following general formula (I). Component (B) which is a Karl Fischer reagent comprising a derivative, imidazole and at least one basic compound selected from imidazole derivatives represented by the following general formula (II) and a solvent which is methyl cellosolve, methanol, chloroform or a mixture thereof. And the amount of component (B) required to render component (A) substantially anhydrous,
To the solvent for moisture measurement which is present in an amount of 0.1 to 1.5 mM excess in terms of iodine, a predetermined amount of the sample to be moisture-measured is added through the septum and thoroughly mixed, and then a fixed amount of Karl Fischer reagent is added. The water content in the sample to be measured is measured up to the water content corresponding to the total amount of the Karl Fischer reagent added, and the water content in the sample to be measured is measured. Method. (In the above formula, R 1 represents a hydrogen atom or a C 1-4 alkyl group, and R 2 represents a C 1-4 alkyl group) (R 3 , R 4 and R 5 each represent a hydrogen atom or a C 1-4 alkyl group, at least one of which is a C 1-4 alkyl group)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61135159A JPH0713636B2 (en) | 1986-06-11 | 1986-06-11 | Moisture measuring solvent and water measuring method using the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61135159A JPH0713636B2 (en) | 1986-06-11 | 1986-06-11 | Moisture measuring solvent and water measuring method using the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62291563A JPS62291563A (en) | 1987-12-18 |
| JPH0713636B2 true JPH0713636B2 (en) | 1995-02-15 |
Family
ID=15145198
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61135159A Expired - Fee Related JPH0713636B2 (en) | 1986-06-11 | 1986-06-11 | Moisture measuring solvent and water measuring method using the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0713636B2 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003500647A (en) * | 1999-05-21 | 2003-01-07 | セデルグレン，アンデルス | Karl Fischer reagent |
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|---|---|---|---|---|
| JP7435172B2 (en) * | 2020-03-31 | 2024-02-21 | 三菱ケミカル株式会社 | Reagent and moisture measurement method |
| CN116626224B (en) * | 2023-06-16 | 2024-03-15 | 永华化学股份有限公司 | Coulomb method Karl Fischer reagent and preparation method and application thereof |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5234957A (en) * | 1975-09-13 | 1977-03-17 | Yuua Kagaku Kougiyou Kk | Method of producing fermented fish powder |
| JPS5515019A (en) * | 1978-07-18 | 1980-02-01 | Mitsubishi Chem Ind Ltd | Solvent for water titration dependent upon karl fischer method |
-
1986
- 1986-06-11 JP JP61135159A patent/JPH0713636B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003500647A (en) * | 1999-05-21 | 2003-01-07 | セデルグレン，アンデルス | Karl Fischer reagent |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62291563A (en) | 1987-12-18 |
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