Determination of 3 Anions in Soil by Ion Chromatography

Ion chromatography was applied to determinnation of Cl^-, SO₄^2- and NO₃^- in soil. The sample (10.000 0 g) was added into 100 mL of ultra-pure water and the mixture was treated by oscillation for 2 h and ultrasonic for 60 min. After centrfugation, the supernanat was filtred through 0.45, 0.22 μm filter succesively. The 3 anions in the filtrate were seperated on Dionex IonPac TM AS18 anion analysis column with 22 mmol·L^-1 of KOH solution as mobile phase, and detected by a conductivity detector. The linearity ranges of Cl^-, SO₄^2- and NO₃^- were 1.00-9.00 mg·L^-1, with detection limits (3s) of 0.006,0.006,0.003 mg·L^-1, respectively. Recovery rates obtained by standard addition method were in the range of 94.0%-96.0%, and RSDs (n=10) were less than 2.0%.