INDIRECT PHOTOMETRIC CHROMATOGRAPHY OF INORGANIC ANIONS USING NAPHTHOLDISULFONATE

The ion exchange separation and identification of common inorganic anions such as F-, Cl-, NO2-, Br-, NO3-, SO42-, I-, and SCN- using the mobile phase 2-naphthol-3,6-disulfonate with indirect photometric detection is described. The mobile phase composition and the sample preparation method, because of their influence on the chromatographic performance, are optimized. This doubly charged, pH-independent mobile phase shows good selectivity towards the separation and detection of the large or highly charged anions such as SO42-, I-, and SCN-. The linear range for SO42- is from 100-0.1 ppm, with a detection limit of 2 pmol and a separation time of 8 min.; The ion exchange separation and identification of common inorganic anions such as F-, Cl-, NO2, Br-, NO3-, SO42-, I-, and SCN- using the mobile phase 2-napthol-3,6-disulfonate with indirect photometric detection is described. The mobile phase composition and the sample preparation method, because of their influence on the chromatographic performance, are optimized. This doubly charged, pH-independent mobile phase shows good selectivity towards the separation and detection of the large or highly charged anions such as SO42-, I-, and SCN-. The linear range for SO42+ is from 100-0.1 ppm, with a detection limit of 2 pmol and a separation time of 8 min.