Determination of Total Iodine in Geological Samples by High Performance Ion Chromatography with Pulsed Amperometric Detection

High performance ion chromatography with pulsed amperometric detection was applied to the determination of total iodine in geological samples.The sample was decomposed by sodium carbonate-zinc oxide sintering at 700 ℃.Sodium sulfite was used as reductant and IonPac AG11 and IonPac AS11 anion exchange column was used for seperating with sodium hydroxide as eluent.Linear relationship between values of peak height and mass fraction of iodine was obtained in the range of 0.16-50 μg·g-1,with detection limit (3s) of 0.08 μg·g-1.The proposed method was applied to the analysis of national standard materials,giving results in consistency with the certified values with RSD′s (n=12) in the range of 2.7%-7.3%.