Study on the Method of Determination of Water-soluble Trifluoroacetic Acid in Soil by Ion Chromatography
An analytical method for the determination of water-soluble trifluoroacetic acid(TFA)in soil was studied.(Objective)Ion chromatography was established to determine the content of water-soluble trifluoroacetic acid in soil.(Methods)The analytical column Dionex IonPac AS11-HC(ϕ4 mm ×250 mm),the guard column DionexTM IonPacTM AG11-HC(ϕ4 mm × 50 mm),mobile phase:10mmol/L potassium hydroxide,flow rate:1.0 mL/min,column temperature:30 ℃,injection volume:250 μL,suppressor current:25 mA,conductivity detector.(Results)The linear relationship of trifluoroacetic acid in the range of 5.0~100.0 μg/L was well,r=0.9998,and the detection limit of trifluoroacetic acid was 1 μg/kg and 4 μg/kg when the sample volume was 20.0 g.The precision of the actual soil samples was 10% and 3.7%,and the recovery rate of the actual soil samples was 82.6%-92.2%.(Conclusion)This method has the advantages of fast and simple pre-processing operation and high accuracy.