IC Determination of Fluoride in Graphite

Sample of graphite was fused with NaOH at 500℃and the melt obtained was dissolved with hot water.The content of F in the sample solution was determined by IC.Dinoex AS15 chromatographic column was used as ion exchange column and 20 mmol ? L~(-1) NaOH was used as eluent with conductivity detector for determination.Linear relationship between values of vpeak area and mass concentration of F was obtained in the range of 0.01—1.0 mg ? L~(-1).The proposed method has been used in the analysis of 14 samples of graphite from 1 area, giving the contents of F~- in the range of 3.16×10~2—2.04×10~3 mg ? kg~(-1) with RSD's(n=11) less than 3.0%.