Determination of Hexafluorophosphate in Waste Water Using Ion Chromatography

An analytical method was developed for the determination of hexafluorophosphate in waste water using ion exclusion chromatography with suppressed conductivity. The separation was performed on an IonPac AG23+IonPac AS23 separate ion exchange column with a flow rate of 1 mL/min, KOH isocratic drenching and inhibited conductivity detection. The collected samples were processed on a 0.22 μm filter membrane, a C18 column, an On-Guard Na column, and then injected into the sample for analysis. The detection limit (S/N=3) of hexafluorophosphate was 0.02 mg/L. The linear coefficient was 0.999 7. The relative standard deviation of the peak area was 1.85%, and the spiked recoveries of waste water ranged from 94.0% to 103.3%. The method is simple and accurate, and can be used for the detection of actual samples.