Determination of Inorganic Fluoride in Brick Tea by Ion Chromatography Conductivity Detector

A simple and rapid method for determination of F-in brick tea by ion chromatography with conductivity detector was studied. The anions were tested on AS18(4 mm×250 mm) anion exchange column using multi-step gradient KOH as eluent. The flow rate of mobile phase was 1.0 ml/min. The correction coefficients were 0.9998 detection limits (3S/N) were found to be 0.01 mg/kg. Recoveries tested by the different lever addition were in the range of 95.0%～106.0%.