Ion chromatography with ultraviolet and amperometric detection for iodide and thiocyanate in concentrated salt solutions

Abstract An ion chromatographic system with ultraviolet (UV) and amperometric (AMP) detectors is described for the highly sensitive detection of iodide and thiocyanate. Solutions of four inorganic salts as mobile phases and three stationary phases were examined. The optimum separation was achieved by using a polymethacrylate-based anion-exchange column and 0.1 M sodium chloride—5 m M sodium phosphate buffer (pH 6.7) as the mobile phase. Conditions were established for UV and AMP detection on a electrochemically pretreated glassy carbon electrode. The method, which has the ability to eliminate most interferences from other anions, could be applied to the direct determination of ppb levels of iodide in sea water.