Development of ion chromatography methods for the determination of trace anions in ultra pure water from power plants

Abstract

A suppressed ion chromatography (IC) technique, using a carbonate/hydrogen carbonate or a hydroxide eluent, has been evaluated as a monitoring tool for the detection of major anions (F-, Cl-, NO3-, PO43- and SO42-) in ultra pure water and condensed steam from thermal power plants. An electrical conductivity detector with an anion-exchange column (IonPac AS14), an auto self-regenerating suppressor (ASRS), and an isocratic high-pressure pump system were used for the detection of low concentrations of inorganic anions. It was shown that the suppressed IC technique provides a suitable means for preventing possible damage to generating equipment in power plants. The detection limits of the method for the anions of interest were lt 0.3 μg/L.

Tehnika supresivne jonske hromatografije (IC) razvijena je za analizu tragova anjona (F-, Cl-, NO3-, PO43- and SO42-) u uzorcima ultra čiste vode. Detektor električne provodljivosti sa kolonom za jonsku izmenu (IonPac AS14) samoregenerišući anjonski supresor (ASRS) i izokratična IC pumpa visokog pritiska uspešno su primenjeni za otkrivanje niskih koncentracija neorganskih anjona. Razvijene su dve IC metode, jedna sa karbonatnim (za analizu NO3 PO43- i SO42- -jona), a druga sa hidroksidnim eluentom (za analizu F- i Cl--jona). Granice detekcije primenjenih metoda bile su: lt 0,3 μg/L (metoda sa karbonatnim eluntom) i lt 0,1 μg/L (metoda sa hidroksidnim eluentom). Na ovaj način razvijene su dve IC metode koje se mogu primeniti za kontrolu tragova anjona u sistemu voda-para u termoelektranama.