Yoshimitsu Seo

Selective gas-chromatographic detection using an ion-selective electrode-II Selective detection of fluorine compounds.

Components in samples are separated on a gas chromatography column using hydrogen as carrier gas. The individual components from the column are passed through a platinum tube heated at 1000 degrees , where they undergo hydrogenolysis, and fluorine compounds are converted into hydrogen fluoride. The hydrogen fluoride is dissolved in a slow stream of an absorption solution, and the fluoride ion concentration in the resulting solution is monitored in a flow-cell with a fluoride ion electrode. The potentiometric output of the cell is converted into a signal, which is proportional to the concentration of fluoride ion, by an antilogarithmic converter, and recorded. The response of the detector to fluorine compounds was about 10,000 times that to an equal quantity of other organic compounds, and 5 x 10(-11) mole of fluorobenzene could be detected.

A dual ion-selective electrode detector for the simultaneous detection of bromine- and chlorine- containing compounds in gas chromatography

Abstract A dual ion-selective electrode gas chromatographic detector which allows the simultaneous detection of chlorine- and bromine-containing compounds through two-channel operation is described. Components eluted from the g.c. column are hydrogenated, the hydrogen chloride and hydrogen bromide produced being absorbed in a standard solution of halide; the ion concentrations in the resulting solution are monitored by chloride- and bromide-selective electrodes. The dual electrode detector gives two chromatograms simultaneously, one selective for chlorine- and bromine-containing compounds and the other for bromine-containing compounds. The response ratio, i.e., the peak area of the readout from the chloride channel divided by that from the bromide channel for the same compound, gives valuable information. The Cl/Br ratio in an eluted molecule can be determined accurately from the response ratio if a standard reference compound is injected simultaneously.

Gas electrode detector for gas chromatography. III. Gas electrode detector for selective detection of sulfur compounds in gasoline.

著者らの開発したガスクロマトグラフ用選択的検出器である,ガス電極検出器のセンサーに,硫化物イオン電極を用い,分離カラムには溶融シリカキャピラリーカラムを用いてガソリン中の硫黄化合物の同定を試みた.市販のレギュラーガソリン{0.01%(w/w)硫黄}を前処理することなく,その0.5μlを分離カラムに注入してクロマトグラムを描いた.定性は保持値と水素キャリヤーガス中でのチオフェン系化合物と非チオフェン系化合物の熱に対する安定性の違いから両者の識別を行った.その結果,ガソリン中に9種類の硫黄化合物(チオフェン,ジメチルジスルフィド,2-メチルチオフェン,3-メチルチオフェン,エチルメチルジスルフィド,2,5-ジメチルチオフェン,2-エチルチオフェン,ジエチルジスルフィド及び2,3-ベンゾチオフェン)を検出した.