Simultaneous Fast Determination of F~-,Cl~-,NO_2~-,Br~-,NO_3~-,HPO_4~(2-) and SO_4~(2-) in Soil Samples by Ion Chromatography

A novel method was developed for the simultaneous determination of F-,Cl-,NO-2,Br-,NO-3,HPO2-4 and SO2-4 in dry soil samples by ion chromatography with a suppressed conductivity detector. The chromatographic separation was established on Metrohm A supp 4 (4×250 mm)anion exchange column,using 2.5 mmol/L Na2CO3+1.7mmol/L NaHCO3 at 0.8 mL/min in flow rate. The corresponding detection limits for the above anions were 0.001 6 mg/L,0.003 2 mg/L,0.004 7 mg/L,0.007 4 mg/L,0.007 6 mg/L,0.011 5 mg/L and 0.008 6 mg/L,respectively,under the optimal conditions,the RSDs for the six consecutive determinations were 1.24%-4.08%(n=6)and the average recovery percentage of the sample detection ranged from 91.% to 103.1%. The method proved to be fast and effective,with simple preprocessing of soil samples,low detection limit,good precision and reliable determination results.